chktex 1.7.1

git-svn-id: svn://tug.org/texlive/trunk@27826 c570f23f-e606-0410-a88d-b1316a301751

63 files changed, 13361 insertions, 487 deletions

diff --git a/Build/source/texk/README b/Build/source/texk/README
index 3359f93d408..a65533b6d96 100644
--- a/Build/source/texk/README
+++ b/Build/source/texk/README
@@ -27,8 +27,8 @@ bibtex8 - ?
 bibtexu - ?
   http://omega.enstb.org/yannis/bibtexu/
 
-chktex 1.6.6 - checked 10apr12
-  http://mirror.ctan.org/support/chktex/ for pdf, otherwise same as
+chktex 1.7.1 - checked 27sep12
+  http://mirror.ctan.org/support/chktex/
   http://download.savannah.gnu.org/releases/chktex/
 
 cjkutils 4.8.3 - checked 11may12
diff --git a/Build/source/texk/chktex/ChangeLog b/Build/source/texk/chktex/ChangeLog
index 30d7cf61ee6..84af563232e 100644
--- a/Build/source/texk/chktex/ChangeLog
+++ b/Build/source/texk/chktex/ChangeLog
@@ -1,3 +1,9 @@
+2012-09-27  Peter Breitenlohner  <peb@mppmu.mpg.de>
+
+	Import chktex-1.7.1.
+	* regex/* (new): Copied from ../web2c/pdftexdir, for MinGW. 
+	* Makefile.am, configure.ac, version.ac: Adapted.
+
 2012-08-31  Peter Breitenlohner  <peb@mppmu.mpg.de>
 
 	* Makefile.am: Install chkweb as linked script.
diff --git a/Build/source/texk/chktex/Makefile.am b/Build/source/texk/chktex/Makefile.am
index 90105364e97..c12f3f575f7 100644
--- a/Build/source/texk/chktex/Makefile.am
+++ b/Build/source/texk/chktex/Makefile.am
@@ -26,7 +26,7 @@ EXTRA_DIST += $(CHKTEX_TREE)-PATCHES
 dist-hook:
 	rm -rf `find $(distdir) -name .svn`
 
-INCLUDES = $(KPATHSEA_INCLUDES)
+INCLUDES = $(REGEX_INCLUDES) $(KPATHSEA_INCLUDES)
 AM_CPPFLAGS = -DKPATHSEA
 AM_CFLAGS = $(WARNING_CFLAGS)
 
@@ -45,6 +45,24 @@ chktex_SOURCES = \
 	$(CHKTEX_TREE)/Utility.h \
 	$(CHKTEX_TREE)/types.h
 
+if MINGW32
+REGEX_INCLUDES = -I$(srcdir)/regex
+chktex_SOURCES += \
+	regex/regex.c \
+	regex/regex.h
+endif MINGW32
+
+## included by regex/regex.c
+EXTRA_chktex_SOURCES = \
+	regex/regcomp.c \
+	regex/regex_internal.c \
+	regex/regex_internal.h \
+	regex/regexec.c
+
+EXTRA_DIST += \
+	regex/COPYING.LIB \
+	regex/README
+
 $(chktex_OBJECTS): $(KPATHSEA_DEPEND)
 
 LDADD = $(KPATHSEA_LIBS)
@@ -54,6 +72,7 @@ man_MANS = \
 	$(CHKTEX_TREE)/chkweb.1 \
 	$(CHKTEX_TREE)/deweb.1
 
+# scripts
 perl_scripts = deweb
 sh_scripts = chkweb
 scriptsdir = texmf/scripts/chktex
@@ -86,10 +105,8 @@ CLEANFILES = $(nodist_bin_SCRIPTS)
 ## Tests
 ##
 TESTS = chktex.test
-
+EXTRA_DIST += $(TESTS)
 TESTS_ENVIRONMENT = CHKTEX_TREE=$(CHKTEX_TREE)
 
-EXTRA_DIST += chktex.test
-
 CLEANFILES += chktest
 
diff --git a/Build/source/texk/chktex/Makefile.in b/Build/source/texk/chktex/Makefile.in
index cdd1d065bcf..cd6b406bbe5 100644
--- a/Build/source/texk/chktex/Makefile.in
+++ b/Build/source/texk/chktex/Makefile.in
@@ -53,6 +53,10 @@ POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
 bin_PROGRAMS = chktex$(EXEEXT)
+@MINGW32_TRUE@am__append_1 = \
+@MINGW32_TRUE@	regex/regex.c \
+@MINGW32_TRUE@	regex/regex.h
+
 DIST_COMMON = $(am__configure_deps) $(dist_pdfdoc_DATA) \
 	$(srcdir)/../../texk/am/script_links.am $(srcdir)/Makefile.am \
 	$(srcdir)/Makefile.in $(srcdir)/config.h.in \
@@ -62,18 +66,16 @@ DIST_COMMON = $(am__configure_deps) $(dist_pdfdoc_DATA) \
 	$(top_srcdir)/../../build-aux/install-sh \
 	$(top_srcdir)/../../build-aux/ltmain.sh \
 	$(top_srcdir)/../../build-aux/missing \
-	$(top_srcdir)/chktex-1.6.6/ChkTeX.tex.in \
-	$(top_srcdir)/chktex-1.6.6/deweb.in $(top_srcdir)/configure \
+	$(top_srcdir)/chktex-1.7.1/deweb.in $(top_srcdir)/configure \
 	../../build-aux/config.guess ../../build-aux/config.sub \
 	../../build-aux/depcomp ../../build-aux/install-sh \
 	../../build-aux/ltmain.sh ../../build-aux/missing \
 	../../build-aux/texinfo.tex ../../build-aux/ylwrap ChangeLog
-@WIN32_TRUE@@WIN32_WRAP_TRUE@am__append_1 = $(wrappers)
+@WIN32_TRUE@@WIN32_WRAP_TRUE@am__append_2 = $(wrappers)
 subdir = .
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/../../m4/kpse-common.m4 \
 	$(top_srcdir)/../../m4/kpse-kpathsea-flags.m4 \
-	$(top_srcdir)/../../m4/kpse-progs.m4 \
 	$(top_srcdir)/../../m4/kpse-warnings.m4 \
 	$(top_srcdir)/../../m4/kpse-win32.m4 \
 	$(top_srcdir)/../../m4/libtool.m4 \
@@ -88,15 +90,24 @@ am__CONFIG_DISTCLEAN_FILES = config.status config.cache config.log \
  configure.lineno config.status.lineno
 mkinstalldirs = $(install_sh) -d
 CONFIG_HEADER = config.h
-CONFIG_CLEAN_FILES = ChkTeX.tmp deweb.pl
+CONFIG_CLEAN_FILES = deweb.pl
 CONFIG_CLEAN_VPATH_FILES =
 am__installdirs = "$(DESTDIR)$(bindir)" "$(DESTDIR)$(bindir)" \
 	"$(DESTDIR)$(texmfdir)" "$(DESTDIR)$(texmfdir)" \
 	"$(DESTDIR)$(man1dir)" "$(DESTDIR)$(configdir)" \
 	"$(DESTDIR)$(pdfdocdir)"
 PROGRAMS = $(bin_PROGRAMS)
+am__chktex_SOURCES_DIST = $(CHKTEX_TREE)/ChkTeX.c \
+	$(CHKTEX_TREE)/ChkTeX.h $(CHKTEX_TREE)/FindErrs.c \
+	$(CHKTEX_TREE)/FindErrs.h $(CHKTEX_TREE)/OpSys.c \
+	$(CHKTEX_TREE)/OpSys.h $(CHKTEX_TREE)/Resource.c \
+	$(CHKTEX_TREE)/Resource.h $(CHKTEX_TREE)/Utility.c \
+	$(CHKTEX_TREE)/Utility.h $(CHKTEX_TREE)/types.h regex/regex.c \
+	regex/regex.h
+@MINGW32_TRUE@am__objects_1 = regex.$(OBJEXT)
 am_chktex_OBJECTS = ChkTeX.$(OBJEXT) FindErrs.$(OBJEXT) \
-	OpSys.$(OBJEXT) Resource.$(OBJEXT) Utility.$(OBJEXT)
+	OpSys.$(OBJEXT) Resource.$(OBJEXT) Utility.$(OBJEXT) \
+	$(am__objects_1)
 chktex_OBJECTS = $(am_chktex_OBJECTS)
 chktex_LDADD = $(LDADD)
 am__DEPENDENCIES_1 =
@@ -143,8 +154,8 @@ CCLD = $(CC)
 LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
 	--mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) \
 	$(LDFLAGS) -o $@
-SOURCES = $(chktex_SOURCES)
-DIST_SOURCES = $(chktex_SOURCES)
+SOURCES = $(chktex_SOURCES) $(EXTRA_chktex_SOURCES)
+DIST_SOURCES = $(am__chktex_SOURCES_DIST) $(EXTRA_chktex_SOURCES)
 am__can_run_installinfo = \
   case $$AM_UPDATE_INFO_DIR in \
     n|no|NO) false;; \
@@ -240,8 +251,6 @@ PACKAGE_TARNAME = @PACKAGE_TARNAME@
 PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
-PDFLATEX = @PDFLATEX@
-PDF_DEPEND = @PDF_DEPEND@
 PERL5 = @PERL5@
 RANLIB = @RANLIB@
 SED = @SED@
@@ -309,23 +318,23 @@ top_srcdir = @top_srcdir@
 #
 #************************************************************************
 ACLOCAL_AMFLAGS = -I ../../m4
-EXTRA_DIST = $(CHKTEX_TREE) $(CHKTEX_TREE)-PATCHES \
-	../../build-aux/relpath chktex.test
-INCLUDES = $(KPATHSEA_INCLUDES)
+EXTRA_DIST = $(CHKTEX_TREE) $(CHKTEX_TREE)-PATCHES regex/COPYING.LIB \
+	regex/README ../../build-aux/relpath $(TESTS)
+INCLUDES = $(REGEX_INCLUDES) $(KPATHSEA_INCLUDES)
 AM_CPPFLAGS = -DKPATHSEA
 AM_CFLAGS = $(WARNING_CFLAGS)
-chktex_SOURCES = \
-	$(CHKTEX_TREE)/ChkTeX.c \
-	$(CHKTEX_TREE)/ChkTeX.h \
-	$(CHKTEX_TREE)/FindErrs.c \
-	$(CHKTEX_TREE)/FindErrs.h \
-	$(CHKTEX_TREE)/OpSys.c \
-	$(CHKTEX_TREE)/OpSys.h \
-	$(CHKTEX_TREE)/Resource.c \
-	$(CHKTEX_TREE)/Resource.h \
-	$(CHKTEX_TREE)/Utility.c \
-	$(CHKTEX_TREE)/Utility.h \
-	$(CHKTEX_TREE)/types.h
+chktex_SOURCES = $(CHKTEX_TREE)/ChkTeX.c $(CHKTEX_TREE)/ChkTeX.h \
+	$(CHKTEX_TREE)/FindErrs.c $(CHKTEX_TREE)/FindErrs.h \
+	$(CHKTEX_TREE)/OpSys.c $(CHKTEX_TREE)/OpSys.h \
+	$(CHKTEX_TREE)/Resource.c $(CHKTEX_TREE)/Resource.h \
+	$(CHKTEX_TREE)/Utility.c $(CHKTEX_TREE)/Utility.h \
+	$(CHKTEX_TREE)/types.h $(am__append_1)
+@MINGW32_TRUE@REGEX_INCLUDES = -I$(srcdir)/regex
+EXTRA_chktex_SOURCES = \
+	regex/regcomp.c \
+	regex/regex_internal.c \
+	regex/regex_internal.h \
+	regex/regexec.c
 
 LDADD = $(KPATHSEA_LIBS)
 man_MANS = \
@@ -333,10 +342,12 @@ man_MANS = \
 	$(CHKTEX_TREE)/chkweb.1 \
 	$(CHKTEX_TREE)/deweb.1
 
+
+# scripts
 perl_scripts = deweb
 sh_scripts = chkweb
 scriptsdir = texmf/scripts/chktex
-nodist_bin_SCRIPTS = $(am__append_1)
+nodist_bin_SCRIPTS = $(am__append_2)
 all_scripts = $(lua_scripts) $(perl_scripts) $(shell_scripts)
 @WIN32_TRUE@@WIN32_WRAP_TRUE@wrappers = $(all_scripts:=.exe)
 @WIN32_TRUE@@WIN32_WRAP_TRUE@runscript = $(top_srcdir)/../../texk/texlive/w32_wrapper/runscript.exe
@@ -409,9 +420,7 @@ $(srcdir)/config.h.in: @MAINTAINER_MODE_TRUE@ $(am__configure_deps)
 
 distclean-hdr:
 	-rm -f config.h stamp-h1
-ChkTeX.tmp: $(top_builddir)/config.status $(top_srcdir)/chktex-1.6.6/ChkTeX.tex.in
-	cd $(top_builddir) && $(SHELL) ./config.status $@
-deweb.pl: $(top_builddir)/config.status $(top_srcdir)/chktex-1.6.6/deweb.in
+deweb.pl: $(top_builddir)/config.status $(top_srcdir)/chktex-1.7.1/deweb.in
 	cd $(top_builddir) && $(SHELL) ./config.status $@
 install-binPROGRAMS: $(bin_PROGRAMS)
 	@$(NORMAL_INSTALL)
@@ -579,6 +588,10 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/OpSys.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/Resource.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/Utility.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/regcomp.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/regex.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/regex_internal.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/regexec.Po@am__quote@
 
 .c.o:
 @am__fastdepCC_TRUE@	$(COMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ $<
@@ -671,6 +684,62 @@ Utility.obj: $(CHKTEX_TREE)/Utility.c
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o Utility.obj `if test -f '$(CHKTEX_TREE)/Utility.c'; then $(CYGPATH_W) '$(CHKTEX_TREE)/Utility.c'; else $(CYGPATH_W) '$(srcdir)/$(CHKTEX_TREE)/Utility.c'; fi`
 
+regex.o: regex/regex.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regex.o -MD -MP -MF $(DEPDIR)/regex.Tpo -c -o regex.o `test -f 'regex/regex.c' || echo '$(srcdir)/'`regex/regex.c
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regex.Tpo $(DEPDIR)/regex.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regex.c' object='regex.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regex.o `test -f 'regex/regex.c' || echo '$(srcdir)/'`regex/regex.c
+
+regex.obj: regex/regex.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regex.obj -MD -MP -MF $(DEPDIR)/regex.Tpo -c -o regex.obj `if test -f 'regex/regex.c'; then $(CYGPATH_W) 'regex/regex.c'; else $(CYGPATH_W) '$(srcdir)/regex/regex.c'; fi`
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regex.Tpo $(DEPDIR)/regex.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regex.c' object='regex.obj' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regex.obj `if test -f 'regex/regex.c'; then $(CYGPATH_W) 'regex/regex.c'; else $(CYGPATH_W) '$(srcdir)/regex/regex.c'; fi`
+
+regcomp.o: regex/regcomp.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regcomp.o -MD -MP -MF $(DEPDIR)/regcomp.Tpo -c -o regcomp.o `test -f 'regex/regcomp.c' || echo '$(srcdir)/'`regex/regcomp.c
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regcomp.Tpo $(DEPDIR)/regcomp.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regcomp.c' object='regcomp.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regcomp.o `test -f 'regex/regcomp.c' || echo '$(srcdir)/'`regex/regcomp.c
+
+regcomp.obj: regex/regcomp.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regcomp.obj -MD -MP -MF $(DEPDIR)/regcomp.Tpo -c -o regcomp.obj `if test -f 'regex/regcomp.c'; then $(CYGPATH_W) 'regex/regcomp.c'; else $(CYGPATH_W) '$(srcdir)/regex/regcomp.c'; fi`
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regcomp.Tpo $(DEPDIR)/regcomp.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regcomp.c' object='regcomp.obj' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regcomp.obj `if test -f 'regex/regcomp.c'; then $(CYGPATH_W) 'regex/regcomp.c'; else $(CYGPATH_W) '$(srcdir)/regex/regcomp.c'; fi`
+
+regex_internal.o: regex/regex_internal.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regex_internal.o -MD -MP -MF $(DEPDIR)/regex_internal.Tpo -c -o regex_internal.o `test -f 'regex/regex_internal.c' || echo '$(srcdir)/'`regex/regex_internal.c
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regex_internal.Tpo $(DEPDIR)/regex_internal.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regex_internal.c' object='regex_internal.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regex_internal.o `test -f 'regex/regex_internal.c' || echo '$(srcdir)/'`regex/regex_internal.c
+
+regex_internal.obj: regex/regex_internal.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regex_internal.obj -MD -MP -MF $(DEPDIR)/regex_internal.Tpo -c -o regex_internal.obj `if test -f 'regex/regex_internal.c'; then $(CYGPATH_W) 'regex/regex_internal.c'; else $(CYGPATH_W) '$(srcdir)/regex/regex_internal.c'; fi`
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regex_internal.Tpo $(DEPDIR)/regex_internal.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regex_internal.c' object='regex_internal.obj' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regex_internal.obj `if test -f 'regex/regex_internal.c'; then $(CYGPATH_W) 'regex/regex_internal.c'; else $(CYGPATH_W) '$(srcdir)/regex/regex_internal.c'; fi`
+
+regexec.o: regex/regexec.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regexec.o -MD -MP -MF $(DEPDIR)/regexec.Tpo -c -o regexec.o `test -f 'regex/regexec.c' || echo '$(srcdir)/'`regex/regexec.c
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regexec.Tpo $(DEPDIR)/regexec.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regexec.c' object='regexec.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regexec.o `test -f 'regex/regexec.c' || echo '$(srcdir)/'`regex/regexec.c
+
+regexec.obj: regex/regexec.c
+@am__fastdepCC_TRUE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT regexec.obj -MD -MP -MF $(DEPDIR)/regexec.Tpo -c -o regexec.obj `if test -f 'regex/regexec.c'; then $(CYGPATH_W) 'regex/regexec.c'; else $(CYGPATH_W) '$(srcdir)/regex/regexec.c'; fi`
+@am__fastdepCC_TRUE@	$(am__mv) $(DEPDIR)/regexec.Tpo $(DEPDIR)/regexec.Po
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	source='regex/regexec.c' object='regexec.obj' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o regexec.obj `if test -f 'regex/regexec.c'; then $(CYGPATH_W) 'regex/regexec.c'; else $(CYGPATH_W) '$(srcdir)/regex/regexec.c'; fi`
+
 mostlyclean-libtool:
 	-rm -f *.lo
 
diff --git a/Build/source/texk/chktex/aclocal.m4 b/Build/source/texk/chktex/aclocal.m4
index 7fbb8b80b65..0a8ae70fecd 100644
--- a/Build/source/texk/chktex/aclocal.m4
+++ b/Build/source/texk/chktex/aclocal.m4
@@ -982,7 +982,6 @@ AC_SUBST([am__untar])
 
 m4_include([../../m4/kpse-common.m4])
 m4_include([../../m4/kpse-kpathsea-flags.m4])
-m4_include([../../m4/kpse-progs.m4])
 m4_include([../../m4/kpse-warnings.m4])
 m4_include([../../m4/kpse-win32.m4])
 m4_include([../../m4/libtool.m4])
diff --git a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/TL-Changes b/Build/source/texk/chktex/chktex-1.6.6-PATCHES/TL-Changes
deleted file mode 100644
index 607d2d5ff34..00000000000
--- a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/TL-Changes
+++ /dev/null
@@ -1,17 +0,0 @@
-Changes applied to the chktex-1.6.6 tree as obtained from:
-	http://mirror.ctan.org/support/chktex/  -- includes ChkTeX.pdf,
-	otherwise the same as
-	http://download.savannah.gnu.org/releases/chktex/chktex-1.6.6.tar.gz
-
-Remove:
-	autom4te.cache/
-	configure
-	install-sh
-	stamp-h.in
-
-Rename:
-	chkweb -> chkweb.sh
-
-Add execute permissions:
-	chkweb.sh
-
diff --git a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/patch-06-extern b/Build/source/texk/chktex/chktex-1.6.6-PATCHES/patch-06-extern
deleted file mode 100644
index f99a34f9f6c..00000000000
--- a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/patch-06-extern
+++ /dev/null
@@ -1,43 +0,0 @@
-	Remove the obsolete ASM_HASHWORD stuff (for Amiga)
-	avoiding extern decls from *.c files.
-
-diff -ur chktex-1.6.6.orig/Utility.c chktex-1.6.6/Utility.c
---- chktex-1.6.6.orig/Utility.c	2010-12-18 22:18:49.000000000 +0100
-+++ chktex-1.6.6/Utility.c	2012-04-16 14:20:46.000000000 +0200
-@@ -31,12 +31,7 @@
- #include "Resource.h"
- #include "OpSys.h"
- 
--#ifdef ASM_HASHWORD
--extern unsigned short HashWord(const char *a);
--typedef unsigned short HASH_TYPE;
--#else
- typedef unsigned long HASH_TYPE;
--#endif
- 
- /***************************** SUPPORT FUNCTIONS ************************/
- 
-@@ -389,14 +384,12 @@
- /*************************** HASH INDEX **************************/
- 
- /*
-- * Hashes a string. The string ought be rather short. We use an asm
-- * version the Amiga; note that this returns an unsigned short instead.
-+ * Hashes a string. The string ought be rather short.
-  *
-  * The algorithm was designed by Peter Weinberger. This version was
-  * adapted from Dr Dobb's Journal April 1996 page 26.
-  */
- 
--#ifndef ASM_HASHWORD
- static unsigned long HashWord(const char *str)
- {
-     register unsigned long h = 0, hbit, c;
-@@ -411,7 +404,6 @@
- 
-     return (h);
- }
--#endif
- 
- /*
-  * Inserts a string into a hash index. Note: You'll have to
diff --git a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/patch-07-kpathsea b/Build/source/texk/chktex/chktex-1.6.6-PATCHES/patch-07-kpathsea
deleted file mode 100644
index d102abd0b6e..00000000000
--- a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/patch-07-kpathsea
+++ /dev/null
@@ -1,28 +0,0 @@
-diff -ur chktex-1.6.6.orig/ChkTeX.c chktex-1.6.6/ChkTeX.c
---- chktex-1.6.6.orig/ChkTeX.c	2010-12-18 22:18:13.000000000 +0100
-+++ chktex-1.6.6/ChkTeX.c	2012-07-23 21:29:45.000000000 +0200
-@@ -27,7 +27,9 @@
-  */
- 
- 
-+#ifndef KPATHSEA
- #include "getopt.h"
-+#endif
- #include "ChkTeX.h"
- #include "OpSys.h"
- #include "Utility.h"
-diff -ur chktex-1.6.6.orig/ChkTeX.h chktex-1.6.6/ChkTeX.h
---- chktex-1.6.6.orig/ChkTeX.h	2010-12-18 22:10:05.000000000 +0100
-+++ chktex-1.6.6/ChkTeX.h	2012-07-23 23:14:51.000000000 +0200
-@@ -38,6 +38,11 @@
- #  include CONFIG_H_NAME
- #endif
- 
-+#ifdef KPATHSEA
-+#include <kpathsea/config.h>
-+#include <kpathsea/getopt.h>
-+#endif
-+
- #include <ctype.h>
- #include <math.h>
- #include <stdio.h>
diff --git a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.pdf b/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.pdf
deleted file mode 100644
index 9bc5f24e639..00000000000
--- a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.pdf
+++ /dev/null
diff --git a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/ChangeLog b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/ChangeLog
index 18880faf5f6..81d0ce801a0 100644
--- a/Build/source/texk/chktex/chktex-1.6.6-PATCHES/ChangeLog
+++ b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/ChangeLog
@@ -1,3 +1,12 @@
+2012-09-27  Peter Breitenlohner  <peb@mppmu.mpg.de>
+
+	Imported chktex-1.7.1 source tree from:
+	  http://download.savannah.gnu.org/
+	* patch-06-extern(removed): Now distributed.
+	* patch-07-kpathsea: Adapted.
+	* patch-08-stpcpy (new): Not everyone has stpcpy().
+	* patch-09-test-output (new): Our Test.out.
+
 2012-07-23  Peter Breitenlohner  <peb@mppmu.mpg.de>
 
 	* patch-07-kpathsea (new): With -DKPATHSEA now using kpathsea.
diff --git a/Build/source/texk/chktex/chktex-1.7.1-PATCHES/TL-Changes b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/TL-Changes
new file mode 100644
index 00000000000..0cbbc649fd5
--- /dev/null
+++ b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/TL-Changes
@@ -0,0 +1,12 @@
+Changes applied to the chktex-1.7.1 tree as obtained from:
+	http://mirror.ctan.org/support/chktex/chktex-1.7.1.tar.gz
+	http://download.savannah.gnu.org/releases/chktex/chktex-1.7.1.tar.gz
+
+Remove:
+	configure
+	install-sh
+	stamp-h.in
+
+Rename:
+	chkweb -> chkweb.sh
+
diff --git a/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-07-kpathsea b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-07-kpathsea
new file mode 100644
index 00000000000..f5ae61eb536
--- /dev/null
+++ b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-07-kpathsea
@@ -0,0 +1,28 @@
+diff -ur chktex-1.7.1.orig/ChkTeX.c chktex-1.7.1/ChkTeX.c
+--- chktex-1.7.1.orig/ChkTeX.c	2012-07-26 12:44:22.000000000 +0200
++++ chktex-1.7.1/ChkTeX.c	2012-09-27 10:08:21.000000000 +0200
+@@ -27,7 +27,9 @@
+  */
+ 
+ 
++#ifndef KPATHSEA
+ #include "getopt.h"
++#endif
+ #include "ChkTeX.h"
+ #include "OpSys.h"
+ #include "Utility.h"
+diff -ur chktex-1.7.1.orig/ChkTeX.h chktex-1.7.1/ChkTeX.h
+--- chktex-1.7.1.orig/ChkTeX.h	2012-08-04 21:28:49.000000000 +0200
++++ chktex-1.7.1/ChkTeX.h	2012-09-27 10:08:21.000000000 +0200
+@@ -38,6 +38,11 @@
+ #  include CONFIG_H_NAME
+ #endif
+ 
++#ifdef KPATHSEA
++#include <kpathsea/config.h>
++#include <kpathsea/getopt.h>
++#endif
++
+ #include <ctype.h>
+ #include <math.h>
+ #include <stdio.h>
diff --git a/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-08-stpcpy b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-08-stpcpy
new file mode 100644
index 00000000000..e2536cd8fcc
--- /dev/null
+++ b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-08-stpcpy
@@ -0,0 +1,17 @@
+diff -ur chktex-1.7.1.orig/FindErrs.c chktex-1.7.1/FindErrs.c
+--- chktex-1.7.1.orig/FindErrs.c	2012-08-08 22:27:57.000000000 +0200
++++ chktex-1.7.1/FindErrs.c	2012-09-27 10:58:01.000000000 +0200
+@@ -33,6 +33,13 @@
+ #include "Utility.h"
+ #include "Resource.h"
+ 
++/* Not everyone has stpcpy() */
++static inline char *
++stpcpy(char *dest, const char *src)
++{
++    return strcpy(dest, src) + strlen(src);
++}
++
+ #if HAVE_PCRE || HAVE_POSIX_ERE
+ 
+ #if HAVE_PCRE
diff --git a/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-09-test-output b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-09-test-output
new file mode 100644
index 00000000000..8206114742c
--- /dev/null
+++ b/Build/source/texk/chktex/chktex-1.7.1-PATCHES/patch-09-test-output
@@ -0,0 +1,27 @@
+diff -ur chktex-1.7.1.orig/Test.out chktex-1.7.1/Test.out
+--- chktex-1.7.1.orig/Test.out	2012-08-09 17:11:32.000000000 +0200
++++ chktex-1.7.1/Test.out	2012-09-27 10:56:14.000000000 +0200
+@@ -418,9 +418,9 @@
+ Message 22 in Test.tex: Comment displayed.
+ % Warning 44 -- user regex -- default message  
+ ^
+-Message 44 in Test.tex: User Regex: intro.
++Message 44 in Test.tex: User Regex:  intro..
+ You should always write a good intro.  
+-                               ^^^^^
++                              ^^^^^^^
+ Message 22 in Test.tex: Comment displayed.
+ % Warning 44 -- user regex -- user message  
+ ^
+@@ -457,9 +457,9 @@
+ Message 36 in Test.tex: You should put a space after parenthesis.
+ Here(on this line only)is a warning $sin(x)$ suppressed. % CHKTEX 35 36  
+                        ^
+-Message 44 in Test.tex: User Regex: -1:Capitalize before references.
++Message 44 in Test.tex: User Regex: 1:Capitalize before references.
+ In section~\ref{sec:3} we have a warning.  
+-   ^^^^^^^^^^^^
++  ^^^^^^^^^^^^^
+ Message 22 in Test.tex: Comment displayed.
+ In section~\ref{sec:4} it is suppressed. % chktex -1  
+                                          ^
diff --git a/Build/source/texk/chktex/chktex-1.6.6/COPYING b/Build/source/texk/chktex/chktex-1.7.1/COPYING
index d4e8cec1128..d4e8cec1128 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/COPYING
+++ b/Build/source/texk/chktex/chktex-1.7.1/COPYING
diff --git a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.c b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.c
index 1af5621f31d..1bddf930e46 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.c
+++ b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.c
@@ -75,9 +75,18 @@ NEWBUF(ReadBuffer, BUFSIZ);
 static const char *Banner =
     "ChkTeX v" PACKAGE_VERSION " - Copyright 1995-96 Jens T. Berger Thielemann.\n"
 #ifdef __OS2__
-    "OS/2 port generated with emx compiler, by Wolfgang Fritsch, <fritsch@hmi.de>"
+    "OS/2 port generated with emx compiler, by Wolfgang Fritsch, <fritsch@hmi.de>\n"
 #elif defined(__MSDOS__)
-    "MS-DOS port by Bj\\o rn Ove Thue, <bjort@ifi.uio.no>"
+    "MS-DOS port by Bj\\o rn Ove Thue, <bjort@ifi.uio.no>\n"
+#endif
+#if HAVE_PCRE
+    "Compiled with PCRE regex support."
+#else
+#if HAVE_POSIX_ERE
+    "Compiled with POSIX extended regex support."
+#else
+    "Compiled with no regex support."
+#endif
 #endif
     "\n";
 
@@ -116,7 +125,7 @@ static const char *HelpText =
     "\n"
     "\n"
     "                         Usage of ChkTeX v" PACKAGE_VERSION "\n"
-    "                         ~~~~~~~~~~~~~~~~~~~~\n"
+    "                         ~~~~~~~~~~~~~~~~~~~~~~\n"
     "\n"
     "                               Template\n"
     "                               ~~~~~~~~\n"
@@ -131,7 +140,7 @@ static const char *HelpText =
     "~~~~~~~~~~~~~\n"
     "    -h  --help      : This text.\n"
     "    -i  --license   : Show distribution information\n"
-    "    -l  --localrc   : Read local .chktexrc formatted  file.\n"
+    "    -l  --localrc   : Read local .chktexrc formatted file.\n"
     "    -d  --debug     : Debug information. Give it a number.\n"
     "    -r  --reset     : Reset settings to default.\n"
     "\n"
@@ -141,6 +150,7 @@ static const char *HelpText =
     "    -e  --erroron   : Makes msg # given an error and turns it on.\n"
     "    -m  --msgon     : Makes msg # given a message and turns it on.\n"
     "    -n  --nowarn    : Mutes msg # given.\n"
+    "    -L  --nolinesupp: Disables per-line suppressions.\n"
     "\n"
     "Output control flags:\n"
     "~~~~~~~~~~~~~~~~~~~~~\n"
@@ -169,7 +179,7 @@ static const char *HelpText =
     "----------------------------------------------------------------------\n"
     "If no LaTeX files are specified on the command line, we will read from\n"
     "stdin.   For explanation of warning/error messages, please consult the\n"
-    "main document ChkTeX.dvi or ChkTeX.ps.\n";
+    "main documentation ChkTeX.dvi, ChkTeX.ps or ChkTeX.pdf.\n";
 
 
 
@@ -184,7 +194,8 @@ enum Quote Quote;
 char VerbNormal[] = "%k %n in %f line %l: %m\n" "%r%s%t\n" "%u\n";
 
 #define DEF(type, name, value)  type name = value;
-OPTION_DEFAULTS STATE_VARS;
+OPTION_DEFAULTS;
+STATE_VARS;
 #undef DEF
 FILE *OutputFile = NULL;
 
@@ -352,7 +363,7 @@ int main(int argc, char **argv)
         }
 
         if (!Quiet || LicenseOnly)
-            fprintf(stderr, Banner);
+            fprintf(stderr, "%s", Banner);
 
         if (CurArg == argc)
             UsingStdIn = TRUE;
@@ -370,7 +381,7 @@ int main(int argc, char **argv)
 
         if ((UsingStdIn && StdInTTY && !Quiet) || LicenseOnly)
         {
-            fprintf(stderr, BigBanner);
+            fprintf(stderr, "%s", BigBanner);
         }
 
         if (!StdOutTTY && PipeOutputFormat)
@@ -378,7 +389,7 @@ int main(int argc, char **argv)
 
         if (LicenseOnly)
         {
-            fprintf(stderr, Distrib);
+            fprintf(stderr, "%s", Distrib);
         }
         else
         {
@@ -414,10 +425,9 @@ int main(int argc, char **argv)
                         Brackets[Count] = 0L;
 
 #define DEF(type, name, value) name = value;
-
-                    STATE_VARS
+                    STATE_VARS;
 #undef DEF
-                        if (UsingStdIn)
+                    if (UsingStdIn)
                     {
                         if (StdInUse)
                             break;
@@ -558,7 +568,7 @@ static void ShowWL(const char *Name, const struct WordList *wl)
 
 
 /*
- * Prints some of the internal flags; mainly for debugging purposes 
+ * Prints some of the internal flags; mainly for debugging purposes
  */
 
 static void ShowIntStatus(void)
@@ -640,6 +650,7 @@ static void ShowIntStatus(void)
         BOOLSTAT("Use stdin", UsingStdIn);
         BOOLSTAT("\\input files", InputFiles);
         BOOLSTAT("Output header errors", HeadErrOut);
+        BOOLSTAT("No line suppressions", NoLineSupp);
     }
 #endif
 }
@@ -675,9 +686,9 @@ static void ResetSettings(void)
 {
 
 #define DEF(type, name, value)  name = value;
-    OPTION_DEFAULTS
+    OPTION_DEFAULTS;
 #undef DEF
-        if (OutputFile != stdout)
+    if (OutputFile != stdout)
     {
         fclose(OutputFile);
         OutputFile = stdout;
@@ -750,6 +761,7 @@ static int ParseArgs(int argc, char **argv)
         {"erroron", required_argument, 0L, 'e'},
         {"msgon", required_argument, 0L, 'm'},
         {"nowarn", required_argument, 0L, 'n'},
+        {"nolinesupp", no_argument, 0L, 'L'},
         {"verbosity", optional_argument, 0L, 'v'},
         {"pipeverb", optional_argument, 0L, 'V'},
         {"debug", required_argument, 0L, 'd'},
@@ -790,7 +802,7 @@ static int ParseArgs(int argc, char **argv)
 
     while (!ArgErr &&
            ((c = getopt_long((int) argc, argv,
-                             "b::d:e:f:g::hH::I::il:m:n:o:p:qrs:t::v::V::w:Wx::",
+                             "b::d:e:f:g::hH::I::il:m:n:Lo:p:qrs:t::v::V::w:Wx::",
                              long_options, &option_index)) != EOF))
     {
         while (c)
@@ -830,6 +842,11 @@ static int ParseArgs(int argc, char **argv)
 
                 nextc = ShiftArg(&optarg);
                 break;
+            case 'L':
+                NoLineSupp = TRUE;
+
+                nextc = ShiftArg(&optarg);
+                break;
             case 'q':
                 Quiet = TRUE;
 
@@ -955,7 +972,7 @@ static int ParseArgs(int argc, char **argv)
                 nextc = ParseBoolArg(&HeadErrOut, &optarg);
                 break;
             case 'W':
-                printf(Banner);
+                printf("%s", Banner);
                 exit(EXIT_SUCCESS);
             case '?':
             default:
diff --git a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.h b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.h
index 3fa1e018ced..eaca3227436 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.h
+++ b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.h
@@ -237,41 +237,54 @@ DEBUGBITS(Debug_BIT)
  MSG(pmNoOpenDir,  etWarn, TRUE, 0, \
      "Could not open the directory `%s'.") \
  MSG(pmNoDebugFlag, etWarn, TRUE, 0, \
-     "This version of doesn't support the -d flag. Please recompile.")
+     "This version of doesn't support the -d flag. Please recompile.")\
+ MSG(pmNoRegexMem,  etErr,  TRUE, 0,\
+     "Unable to allocate regular expressions - no memory?\n")\
+ MSG(pmRegexCompileFailed,  etWarn,  TRUE, 0,\
+     "Compilation of regular expression %s failed with error %s.\n")\
+ MSG(pmRegexMatchingError,  etErr,  TRUE, 0,\
+     "PCRE matching error %d.\n") \
+ MSG(pmSuppTooHigh,  etWarn,  TRUE, 0,\
+     "Warning %d is numbered too high (max %d) and won't be suppressed.\n") \
+MSG(pmLongLines,  etWarn,  TRUE, 0,\
+     "ChkTeX does not handle lines over %d bytes correctly.  Some errors and line numbers may be wrong in this file.")
+
 #undef MSG
 #define MSG(num, type, inuse, ctxt, text) num,
-     enum PrgErrNum
-     {
-         PRGMSGS pmMaxFault
-     };
+enum PrgErrNum
+{
+    PRGMSGS pmMaxFault
+};
 #undef MSG
 
-     extern struct ErrMsg PrgMsgs[pmMaxFault + 1];
-
-     struct ErrInfo
-     {
-         char *Data;
-         const char *LineBuf;
-         const char *File;
-         unsigned long Line, Column, ErrLen;
-         enum
-         {
-             efNone = 0x00,
-             efNoItal = 0x01,
-             efItal = 0x02
-         } Flags;
-     };
+extern struct ErrMsg PrgMsgs[pmMaxFault + 1];
+
+struct ErrInfo
+{
+    char *Data;
+    const char *LineBuf;
+    const char *File;
+    unsigned long Line, Column, ErrLen;
+    enum
+    {
+        efNone   = 0x00,
+        efNoItal = 0x01,
+        efItal   = 0x02,
+        efNoMath = 0x04,
+        efMath   = 0x08
+    } Flags;
+};
 
-     extern char *ReadBuffer;
-     extern char *CmdBuffer;
-     extern char *TmpBuffer;
+extern char *ReadBuffer;
+extern char *CmdBuffer;
+extern char *TmpBuffer;
 
-     extern const char BrOrder[NUMBRACKETS + 1];
+extern const char BrOrder[NUMBRACKETS + 1];
 
-     extern unsigned long Brackets[NUMBRACKETS];
+extern unsigned long Brackets[NUMBRACKETS];
 
 
-     extern FILE *OutputFile, *InputFile;
+extern FILE *OutputFile, *InputFile;
 
 #define OPTION_DEFAULTS \
   DEF(int, GlobalRC,    TRUE) \
@@ -287,37 +300,41 @@ DEBUGBITS(Debug_BIT)
   DEF(char *, OutputFormat, VerbNormal) \
   DEF(char *, PipeOutputFormat, NULL) \
   DEF(const char *, Delimit, ":") \
-  DEF(long,  DebugLevel, 0)
+  DEF(long,  DebugLevel, 0) \
+  DEF(int,  NoLineSupp, FALSE)
 
 #define STATE_VARS \
   DEF(enum ItState, ItState, itOff) /* Are we doing italics? */ \
   DEF(int, AtLetter, FALSE) /* Whether `@' is a letter or not. */ \
   DEF(int, InHeader, TRUE)  /* Whether we're in the header */ \
   DEF(int, VerbMode, FALSE) /* Whether we're in complete ignore-mode */ \
-  DEF(long, MathMode, 0)     /* Whether we're in math mode or not */ \
-  DEF(const char *, VerbStr, "")   /* String we'll terminate verbmode upon */ \
+  DEF(long, MathMode, 0)    /* Whether we're in math mode or not */ \
+  DEF(const char *, VerbStr, "")     /* String we'll terminate verbmode upon */ \
   DEF(unsigned long, ErrPrint, 0)    /* # errors printed */ \
   DEF(unsigned long, WarnPrint, 0)   /* # warnings printed */ \
-  DEF(unsigned long, UserSupp, 0)    /* # user suppressed warnings */
+  DEF(unsigned long, UserSupp, 0)    /* # user suppressed warnings */ \
+  DEF(unsigned long, LineSupp, 0)    /* # warnings suppressed on a single line */ \
+  DEF(unsigned long long, FileSuppressions, 0)     /* # warnings suppressed in a file */ \
+  DEF(unsigned long long, UserFileSuppressions, 0) /* # User warnings suppressed in a file */
 
 #define DEF(type, name, value) extern type name;
-     OPTION_DEFAULTS STATE_VARS
+OPTION_DEFAULTS STATE_VARS
 #undef DEF
-     extern struct Stack CharStack, InputStack, EnvStack;
+extern struct Stack CharStack, InputStack, EnvStack;
 
-     enum Quote
-     {
-         quLogic,
-         quTrad
-     };
+enum Quote
+{
+    quLogic,
+    quTrad
+};
 
-     extern enum Quote Quote;
-     extern int StdInTTY, StdOutTTY, UsingStdIn;
+extern enum Quote Quote;
+extern int StdInTTY, StdOutTTY, UsingStdIn;
 
-     int main(int argc, char **argv);
-     void PrintPrgErr(enum PrgErrNum, ...);
-     void ErrPrintf(const char *fmt, ...);
+int main(int argc, char **argv);
+void PrintPrgErr(enum PrgErrNum, ...);
+void ErrPrintf(const char *fmt, ...);
 
-     extern char *PrgName;
+extern char *PrgName;
 
 #endif /* CHKTEX_H */
diff --git a/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.pdf b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.pdf
new file mode 100644
index 00000000000..4bebc93ed6f
--- /dev/null
+++ b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.pdf
diff --git a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.tex.in b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.tex.in
index aa6e61d2a5e..5ec07632ad9 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.tex.in
+++ b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.tex.in
@@ -96,10 +96,10 @@
 \section{Introduction}
 
 This program has been written in frustration because some constructs in
-\LaTeX\ are sometimes non-intuitive, and easy to forget. It is 
+\LaTeX\ are sometimes non-intuitive, and easy to forget. It is
 \emph{not} a replacement for the built-in checker in \LaTeX\@; however it
 catches some typographic errors \LaTeX\ oversees. In other words, it
-is Lint for \LaTeX. Filters are also provided for checking the 
+is Lint for \LaTeX. Filters are also provided for checking the
 \LaTeX\ parts of CWEB documents.
 
 It is written in ANSI C and compiles silently under GCC using
@@ -109,8 +109,8 @@ Full source included.
 
 The program also supports output formats suitable for further
 processing by editors or other programs, making errors easy to cycle through.
-Software is provided for beautifully interfacing against the 
-AUC-\TeX\ Emacs mode, CygnusED, GoldEd and various Amiga message browsers.
+Software is provided for beautifully interfacing with the
+AUC\TeX\ Emacs mode.
 
 The program itself does not have any machine requirements; However compiling
 for other platforms has not been done for a long time now so the code has been
@@ -163,6 +163,7 @@ and configurations.
         available.
       \item Space in front of footnotes.
       \item Bogus characters following commands.
+      \item Ability to suppress warnings on a single line.
       \end{itemize}
 %latex
     \end{flushleft}
@@ -182,7 +183,7 @@ and configurations.
 \item Flexible output handling. Has some predefined formats and lets
   the user specify his own format.  Uses a \Cmd{printf()} similar
   syntax. \Cmd{lacheck} compatible mode included for interfacing with
-  the AUC-\TeX\ Emacs mode.
+  the AUC\TeX\ Emacs mode.
 \item Written in ANSI C\@. \Cmd{configure} script included for easy
   setup and installation on UNIX systems.
 \end{itemize}
@@ -225,8 +226,8 @@ along   with  this  program;  if  not,  write  to:
 
 \section{Availability}
 
-This program will be uploaded to CTAN\@; thus it can be
-found at any mirrors of those.
+This program is on CTAN\@; thus it can be found at any mirrors of those.
+It is also part of TeX Live 2011.
 
 \section{Installation}
 
@@ -237,7 +238,7 @@ A few words on installation on various platforms:
   \Cmd{make~install}. To make sure everything proceeded correctly,
   type \Cmd{make~check}.  If you don't have superuser privileges and thus
   access to the default system areas, you should type
-  \Cmd{configure~--help} to help you set up correct paths.
+  \Cmd{configure~-{}-help} to help you set up correct paths.
 
   If you haven't installed any software like this before, that is
   distributed in source form, here are some guidelines to help you
@@ -260,13 +261,24 @@ A few words on installation on various platforms:
   \item Now, we can configure the program.  There are some
     configuration options you should know about:
     \begin{description}
-    \item[\Cmd{--enable-emacs-hack}:] Install a small file which
-      adds \chktex\ to the command menu of AUC-\TeX. This is to be
+    \item[\Cmd{-{}-enable-pcre}:] Allows using PCRE (perl compatible
+      regular expressions) for use defined warnings.  The default is
+      to use PCRE if it is installed on your system as determined by
+      \Cmd{pcre-config}.  You can use \Cmd{-{}-disable-pcre} if you
+      plan to distribute this for systems in which you cannot ensure
+      PCRE will be installed.
+
+      User defined regular expressions are defined using
+      \texttt{UserWarnRegex} in the \rsrc\ file.  See warning~44 for
+      more information.
+
+    \item[\Cmd{-{}-enable-emacs-hack}:] Install a small file which
+      adds \chktex\ to the command menu of AUC\TeX. This is to be
       considered as a hack, and may break in future versions of
-      AUC-\TeX. It works fine under AUC-\TeX\ v2.9, though.
+      AUC\TeX. It works fine under AUC\TeX\ v2.9, though.
 
       This option needs the path of your elisp directory as argument,
-      e.g. \Cmd{--enable-emacs-hack=/home/myself/elisp} or similar.
+      e.g. \Cmd{-{}-enable-emacs-hack=/home/myself/elisp} or similar.
 
       You'll also have to add the following line to your \Cmd{.emacs}
       file:
@@ -274,10 +286,10 @@ A few words on installation on various platforms:
 (require 'chktex)
 \end{verbatim}
       You can now access \chktex\ from the \Cmd{Command} menu in
-      AUC-\TeX. To cycle through the messages, type \verb#C-x `#.
+      AUC\TeX. To cycle through the messages, type \verb#C-x `#.
 
-    \item[\Cmd{--enable-lacheck-replace}] This enables a quick
-      hack for making the AUC-\TeX\ Emacs mode use \chktex\ instead of
+    \item[\Cmd{-{}-enable-lacheck-replace}] This enables a quick
+      hack for making the AUC\TeX\ Emacs mode use \chktex\ instead of
       lacheck. This is done by installing a stub script which
       ``overrides'' the original lacheck executable.
 
@@ -285,10 +297,10 @@ A few words on installation on various platforms:
       significantly less elegant --- in computing terms, this is the
       ``brute force'' approach.
 
-    \item[\Cmd{--enable-debug-info}] \chktex\ has an ability to spit
+    \item[\Cmd{-{}-enable-debug-info}] \chktex\ has an ability to spit
       out various diagnostic messages using the \Cmd{-d} flag. This
       behaviour is on by default. By adding the flag
-      \Cmd{--disable-debug-info} to the commandline, this will not be
+      \Cmd{-{}-disable-debug-info} to the commandline, this will not be
       compiled in.
 
       This may be useful if you're running short of disk space (the
@@ -345,7 +357,7 @@ A few words on installation on various platforms:
   file, and edit it appropiately, for more
   comfort.  This should not be necessary, though, at least not the
   first time.
-  
+
   Finally, you may now compile and link all \verb@.c@ files.  Do not
   forget to define \Cmd{HAVE\_CONFIG\_H} to 1 (on the command-line,
   for instance).  If the \Cmd{config.h} you wish to use has another
@@ -412,17 +424,17 @@ options:
 \item[Misc.\ options:] General options which aren't related to some
   specific subpart of \chktex.
   \begin{description}
-  \item[\texttt{-h [--help]}] Gives you a command summary.
-  \item[\texttt{-i [--license]}] Shows distribution information.
-  \item[\texttt{-l [--localrc]}] Reads a resource-file formatted
+  \item[\texttt{-h [-{}-help]}] Gives you a command summary.
+  \item[\texttt{-i [-{}-license]}] Shows distribution information.
+  \item[\texttt{-l [-{}-localrc]}] Reads a resource-file formatted
     as the global resource-file \rsrc, in addition to the global
     resource-file. This option needs the name of the resource-file
     as a parameter. See also \texttt{-g}.
-  \item[\texttt{-r [--reset]}] This will reset all settings to their
+  \item[\texttt{-r [-{}-reset]}] This will reset all settings to their
     defaults. This may be useful if you use the \texttt{CMDLINE}
     directive in your \rsrc\ file, and wish to do something
     unusual.
-  \item[\texttt{-d [--debug]}] Needs a numeric argument; a bitmask
+  \item[\texttt{-d [-{}-debug]}] Needs a numeric argument; a bitmask
     telling what to output.  The values below may be added in order
     to output multiple debugging info.
 
@@ -439,27 +451,30 @@ options:
 
     It is possible to install versions of \chktex\ that ignore this
     flag; this means that it is not certain that this flag works.
-  \item[\texttt{-W [--version]}] Displays version information, and exits.
+  \item[\texttt{-W [-{}-version]}] Displays version information, and exits.
   \end{description}
 \item[Muting warning messages:] Controls whether and in what form
   error messages will appear. Usually they accept a specific warning
   number (e.g.\ \Cmd{-w2}), but you may also say \Cmd{all} (e.g.\
   \Cmd{-wall}) which does the operation on \emph{all} warnings.
   \begin{description}
-  \item[\texttt{-w [--warnon]}] Makes the message number passed as
+  \item[\texttt{-w [-{}-warnon]}] Makes the message number passed as
     parameter a warning and turns it on.
-  \item[\texttt{-e [--erroron]}] Makes the message number passed as
+  \item[\texttt{-e [-{}-erroron]}] Makes the message number passed as
     parameter an error and turns it on.
-  \item[\texttt{-m [--msgon]}] Makes the message number passed as
+  \item[\texttt{-m [-{}-msgon]}] Makes the message number passed as
     parameter a message and turns it on. Messages are not counted.
-  \item[\texttt{-n [--nowarn]}] Turns the warning/error number passed
+  \item[\texttt{-n [-{}-nowarn]}] Turns the warning/error number passed
     as a parameter off.
+  \item[\texttt{-L [-{}-nolinesupp]}] Turns off suppression of messages
+    on a per line basis.  This is meant to be used to ensure that no new
+    errors have crept into a document while editing.
   \end{description}
 \item[Output control flags:] Determines the appearance and
   destination of the error reports.
   \begin{description}
-  \item[\texttt{-q [--quiet]}] Shuts up about copyright information.
-  \item[\texttt{-o [--output]}] Normally, all errors are piped to \texttt{stdout}.
+  \item[\texttt{-q [-{}-quiet]}] Shuts up about copyright information.
+  \item[\texttt{-o [-{}-output]}] Normally, all errors are piped to \texttt{stdout}.
     Using this option with a parameter, errors will be sent to the
     named file instead. Only information relative to the \LaTeX\ file
     will be sent to that file. Memory problems and similar will as as
@@ -468,7 +483,7 @@ options:
     (\Cmd{foobar.\$cl} under MS-DOS), \Cmd{foobar} being the name of
     the file.  See also \Cmd{-b}.
 
-  \item[\texttt{-v [--verbosity]}] Specifies how much and how you
+  \item[\texttt{-v [-{}-verbosity]}] Specifies how much and how you
     wish the error reports to be displayed. This is specified in the
     \rsrc\ file; we'll list the default values below. If you wish,
     you may thus edit the \rsrc\ file to add or modify new formats.
@@ -514,7 +529,7 @@ File:Line:Column:Warning number:Warning message
       longer time to parse, but much more informative in use.
     \end{description}
 
-  \item[\texttt{-f [--format]}] Specifies the format of the output.
+  \item[\texttt{-f [-{}-format]}] Specifies the format of the output.
     This is done using a format similar to \Cmd{printf()}, where we
     support the specifiers listed below.
 
@@ -554,7 +569,7 @@ File:Line:Column:Warning number:Warning message
     file; read that for seeing how each format is implemented. If
     you find yourself using a particular format often by using the
     -f switch, consider putting it in the \rsrc\ file instead.
-  \item[\texttt{-V [--pipeverb]}] Which entry we'll use in the \rsrc\
+  \item[\texttt{-V [-{}-pipeverb]}] Which entry we'll use in the \rsrc\
     file whenever \texttt{stdout} isn't a terminal.
 
     The default is to use the same mode as specified with the
@@ -569,7 +584,7 @@ File:Line:Column:Warning number:Warning message
 setenv LESS -r
 \end{verbatim}
 
-  \item[\texttt{-p [--pseudoname]}] With this switch, you can provide
+  \item[\texttt{-p [-{}-pseudoname]}] With this switch, you can provide
     the filename which will be used when we report the errors. This
     may be useful in scripts, especially when doing pipes. It is in
     other words similar to C's \verb@#line@ directive.
@@ -578,7 +593,7 @@ setenv LESS -r
     this one in turn \verb@\@\verb@input@ are presented under their original
     names. This seems most logical to me.
 
-  \item[\texttt{-s [--splitchar]}] String to use instead of the
+  \item[\texttt{-s [-{}-splitchar]}] String to use instead of the
     colons when doing \texttt{-v0}; e.g.\ this string will be output
     between the fields.
 
@@ -590,23 +605,23 @@ setenv LESS -r
   any parameter.
 
   \begin{description}
-  \item[\texttt{-b [--backup]}] If you use the \texttt{-o} switch, and the
+  \item[\texttt{-b [-{}-backup]}] If you use the \texttt{-o} switch, and the
     named outputfile exists, it will be renamed to \texttt{filename.bak}.
-  \item[\texttt{-I [--inputfiles]}] Execute \verb@\@\verb@input@
+  \item[\texttt{-I [-{}-inputfiles]}] Execute \verb@\@\verb@input@
     statements; e.g.\ include the file in the input. Our input parsing
     does of course nest; we use an input-stack to keep track of this.
-  \item[\texttt{-H [--headererr]}] Show errors found in front of the
+  \item[\texttt{-H [-{}-headererr]}] Show errors found in front of the
     \verb@\begin{document}@ line. Some people keep \emph{lots} of
     pure \TeX\ code there, which errors can't be detected reliably
     (in other words, we will in most cases just produce a lot of
     garbage).
-  \item[\texttt{-g [--globalrc]}] Read in the global resource file.  This
+  \item[\texttt{-g [-{}-globalrc]}] Read in the global resource file.  This
     switch may be useful together with the \texttt{-l} option.
-  \item[\texttt{-t [--tictoc]}] Display a twirling baton, to show that
+  \item[\texttt{-t [-{}-tictoc]}] Display a twirling baton, to show that
     we're working. \texttt{-v0} does an \texttt{-t0}, too, as it assumes
     that the user then uses the program non-interactively.  This is
     now a no-op.
-  \item[\texttt{-x [--wipeverb]}] Ignore the ``\verb@\verb@'' command
+  \item[\texttt{-x [-{}-wipeverb]}] Ignore the ``\verb@\verb@'' command
     found within the \LaTeX\ file and its argument is completely by
     the checking routines.  This is done by simply overwriting them.
     If you somehow don't like that (for instance, you would like to
@@ -627,16 +642,15 @@ following keycombinations:
 \end{tabular}
 \smallskip
 
-By default, we're using the 1994 version of GNU's \Cmd{getopt()}
-routine.
+By default, we use GNU's \Cmd{getopt()} routine.
 
 \begin{itemize}
 \item Options may be given in any order; the names of the \LaTeX-files
   do not have to be the last arguments. This behaviour may be turned
   off by creating an environment variable named \Cmd{POSIXLY\_CORRECT}.
-\item The special argument \Cmd{--} forces an end of
+\item The special argument \Cmd{-{}-} forces an end of
   option-scanning.
-\item Long-named options begin with \Cmd{--} instead of \Cmd{-}.
+\item Long-named options begin with \Cmd{-{}-} instead of \Cmd{-}.
   Their names may be abbreviated as long as the abbreviation is unique
   or is an exact match for some defined option. If they have an
   argument, it follows the option name in the argument, separated from
@@ -647,11 +661,13 @@ routine.
 
 You should also take a look at the \rsrc\ file. As it is
 self-documenting, you should be able to get the meaning of each
-keyword by simply reading the file. The method for \emph{finding it},
-however, has grown rather complex. An outline is given below.
+keyword by simply reading the file. In fact, since not all options
+are described in this documentation it is necessary that you read
+the \rsrc\ file in order to understand them all. The method for
+\emph{finding it} has grown rather complex. An outline is given below.
 
-If \chktex\ finds multiple files when searching, each and everyone
-will be read in the order specified below. The \Cmd{Keyword = \{ item
+If \chktex\ finds multiple files when searching, each and every one
+will be read in the order specified below. The \Cmd{Keyword = \{ item
   item \dots \}} may thus be necessary to reset previously defined
 lists.
 
@@ -661,7 +677,7 @@ In this list, \Cmd{\$foo} is assumed to be the environment variable
 \begin{enumerate}
 \item First, we'll take a look at the directory which was specified as
   \Cmd{DATADIR} during compilation. On UNIX boxes, this usually
-  evaluates to something similar to 
+  evaluates to something similar to
   \Cmd{/usr/local/share/chktexrc}, under MS-DOS it is set
   to \Cmd{\BS{}emtex\BS{}data\BS{}chktexrc}.
 
@@ -693,15 +709,66 @@ If you for some reason wish to undo what the previous files may have
 done, you may say \Cmd{CmdLine \{ -g0 -r \}} somewhere in the \rsrc\
 file; this will reset all previous settings.
 
+\subsubsection{Per Line and File Suppressions}
+
+There are many cases in which \chktex{} will give a warning about a
+construct which, although it usually indicates a mistake, is
+intentional.  In these cases it can be extremely annoying to have
+this message appear everytime \chktex{} is run.  For this reason you
+can use \LaTeX{} comments to suppress a certain message on a single
+line.  This can be done by adding a (case-insensitive) comment at the
+end of the line of the form
+\begin{center}
+  \verb+% checktex ##+
+\end{center}
+where \verb+##+ is the number of the message to be suppressed.
+For example the line
+\begin{center}
+  \verb+$[0,\infty)$+\\*
+\end{center}
+will produce a warning (number 9) about mismatched \verb+]+ and \verb+)+.
+However the lines
+\begin{center}
+  \verb+$[0,\infty)$ % chktex 9+\\*
+  \verb+$[0,\infty)$ % ChkTeX 9+\\*
+\end{center}
+will not produce such a message.  In this case, message number 17 will
+still appear at the end, stating that the numbers of \verb+]+ and
+\verb+)+ don't match for the entire file.
+
+To suppress two different errors on the same line you will need two
+instances of \verb+chktex+ in the comment.  This format is a little
+cumbersome, but it shouldn't be needed often, and hopefully will help
+avoid accidental suppressions.
+\begin{center}
+  \verb+Jordan--H\"older on $[0,\infty)$ % chktex 8 chktex 9+\\*
+\end{center}
+
+One problem inherent in line-by-line suppressions is that during editing
+another error of the same type may creep into the same line.  Therefore,
+I suggest using the \texttt{-L} or \texttt{-{}-nolinesupp} option to
+disallow line based suppressions once just before the document is finished.
+At that point you should go back over all the warnings and decide if they
+should be fixed.
+
+In addition to line-specific suppressions, you can create a suppression which will be in effect for the remainder of the file.
+This can be used, for example, to turn off warning 18 (about \verb+"+) in a file which uses a package (like \Cmd{babel}) where \verb+"+ is an active character.
+The syntax is nearly the same, namely
+\begin{center}
+  \verb+% checktex-file ##+
+\end{center}
 
 \subsubsection{Hints}
 I've tried to collect some advice that may be useful --- if you have a
 favourite hint, feel free to send it to me!
 
 \begin{itemize}
-\item If you use \Cmd{german.sty}; it may be wise to put \Cmd{-n18} in
+\item If you use \Cmd{german.sty} or several of \Cmd{babel} languages
+  which use \verb+"+ as an active character; it may be wise to put \Cmd{-n18} in
   the \Cmd{CmdLine} entry in the \rsrc\ file. This will probably reduce
-  the amount of false warnings significantly.
+  the amount of false warnings significantly. Alternately, you can put
+  \verb+% checktex-file 18+ in your files which use one of these packages so
+  that other files will still have these checks performed.
 \item Put \Cmd{-v} in the \Cmd{CmdLine} entry of the \rsrc\ file; this
   makes the fancy printing the default.
 \item If you're working on a large project, it may pay off to make a
@@ -715,7 +782,7 @@ favourite hint, feel free to send it to me!
   of your \LaTeX\ file:
 \begin{verbatim}
 % ChkTeX will ignore material within this environment
-\newenvironment{ignore}{}{} 
+\newenvironment{ignore}{}{}
 \end{verbatim}
   In addition, you should add the item \Cmd{ignore} to the \Cmd{VerbEnvir}
   entry in the \rsrc\ file.
@@ -738,14 +805,20 @@ have the first half of their argument wiped if the argument stretches
 over two lines. We will, however, take care not to wipe parenthesis
 in such cases, in order to avoid false warnings.
 
+Long lines are broken up into chunks and handled separately.  The exact
+length is platform dependent, though is guaranteed to be at least 256 bytes.
+The first portions of the line will have line numbers that are 1 less than
+they should be.  Some errors can be missed and some can be added erroneously.
+A warning will be issued if lines are too long.
+
 Before submitting a bug report, please first see whether the problem can be
-solved by editing the \rsrc\ file appropiately.
+solved by editing the \rsrc\ file appropriately.
 
 
 
 \subsection{ChkWEB}
 
-This  shell  script is provided for checking CWEB files.  The template is
+This shell script is provided for checking CWEB files.  The template is
 as follows:
 \begin{verbatim}
 chkweb [options] file1 file2 ...
@@ -753,7 +826,7 @@ chkweb [options] file1 file2 ...
 As you may see from the script, it is only a trivial interface towards
 \texttt{deweb} and \chktex.  It does not support any individual options
 on the command line --- all options found will be passed onto \chktex.
-If \Cmd{--} or a filename is found, the remaining parameters will be
+If \Cmd{-{}-} or a filename is found, the remaining parameters will be
 ignored.
 The  only  real  intelligence  it  features  is  that it will try to append
 \verb@.w@ to filenames it can't find.
@@ -818,6 +891,11 @@ keyword in the \rsrc\ file which controls the discussed warning.
   is an error as these are ignored by \LaTeX. In most cases, you would
   like to have a real space there.
 
+  You can also specify regular expressions to match commands which can
+  safely be terminated with a space.  They are specified in in the
+  \rsrc\ file in \texttt{[]}, which in some other cases is used to
+  indicate case-insensitive matching.
+
   \begin{errexam}
     \verb@\LaTeX@\underline{\tt }\verb@is a typesetter.@ \\*
     \LaTeX is a typesetter. \\*
@@ -934,12 +1012,23 @@ keyword in the \rsrc\ file which controls the discussed warning.
     Alphabetic character & \texttt{HyphDash} \\*
   \end{tabular}
 
-  This is more or less correct, according to my references.  Hopefully
-  this check can be even more improved (suggestions?).
+  This is more or less correct, according to my references.  One
+  complication is that most often a hyphen (single dash) is desired
+  between letters, but occasionally an n-dash (double dash) is
+  required.  This is the case for theorems named after two people
+  e.g.\ Jordan--H\"older.  A hyphen would indicate that it was one
+  person with a hyphenated name e.g.\ Gregorio Ricci-Curbastro.
+  In my experience this is rare enough to be dealt with via line
+  based suppressions.  There is still the problem that no warning
+  will be raised for Jordan-H\"older, so care must still be taken.
+
+  Some manuals---particularly American manuals---also suggest
+  \emph{not} adding space around an m-dash (triple dash).
+  Hopefully this check can be improved even more (suggestions?).
 
   \begin{errexam}
     \verb@It wasn't anything @\underline{\tt-}\verb@ just a 2@\underline
-    {\tt---}\verb@3 star@\underline{\tt--}\verb@shots.@ \\*
+    {\tt-{}-{}-}\verb@3 star@\underline{\tt-{}-}\verb@shots.@ \\*
     It wasn't anything - just a 2---3 star--shots. \\*
     \smallskip
     \verb@It wasn't anything --- just a 2--3 star-shots@ \\*
@@ -987,6 +1076,9 @@ keyword in the \rsrc\ file which controls the discussed warning.
   previously said \verb@\frenchspacing@, you'll have incorrect
   spacing, which one should avoid if possible.
 
+  You can also specify case-insensitive abbreviations in \texttt{[]}, though
+  only the first letter is actually case-insensitive.
+
   \begin{errexam}
     \verb@This is an example, i.e.@\underline{\tt\ }\verb@an demonstration.@ \\*
     This is an example, i.e. an demonstration.        \\*
@@ -1082,10 +1174,14 @@ keyword in the \rsrc\ file which controls the discussed warning.
   \end{errexam}
 \end{errdesc}
 
-\Keyword{Userwarn}
-\begin{errdesc}{User-specified pattern found.}
-  A substring  you've specified using \texttt{USERWARN} in the \rsrc\ file,
-  has been found.
+\Keyword{UserWarn}
+\begin{errdesc}{User-specified pattern found: \%s.}
+  A substring you've specified using \texttt{UserWarn} in the \rsrc\ file,
+  has been found.  See also warning~44 which allows using regular
+  expressions.  You can also specify case-insensitive versions in
+  \texttt{[]}.
+  % Normally I would use a ref here, but if the numbers change that would be
+  % hugely backwards incompatible.  Also it would require adding special label code.
 \end{errdesc}
 
 \begin{errdesc*}{This command might not be intended.}
@@ -1106,8 +1202,8 @@ keyword in the \rsrc\ file which controls the discussed warning.
   \chktex\ dumps all comments it finds, which in some cases is useful.
   I usually keep all my notes in the comments, and like to review them
   before I ship the final version. For commenting out parts of the
-  document, the \Cmd{comment} environment is better suited.
-
+  document, the \Cmd{comment} environment is better suited. Setting
+  this warning allows you to see notes you have left in comments.
 \end{errdesc*}
 
 
@@ -1133,9 +1229,8 @@ keyword in the \rsrc\ file which controls the discussed warning.
   \rsrc\ file).  Sometimes, this space may cause that the word and the
   index happens on separate pages, if a pagebreak happens just there.
 
-  You might also use this warning to warn you about spaces in front of
-  footnotes; however, the warning text may not be entirely correct
-  then.
+  Warning~42 is similar in that it warns about spaces in front of footnotes.
+  The difference is that the warning text makes more sense for that case.
 
   \begin{errexam}
     \verb@Indexing text@\underline{\tt\ }\verb@\index{text} is fun!@ \\*
@@ -1147,7 +1242,7 @@ keyword in the \rsrc\ file which controls the discussed warning.
 \begin{errdesc}{You might wish to put this between a pair of `\{\}'}
 
   This warning is given whenever \chktex\ finds a \Cmd{\^{ }}' or a
-  \Cmd{\_} followed by either two or more numberic digits or two or
+  \Cmd{\_} followed by either two or more numeric digits or two or
   more alphabetic characters.  In most situations, this means that
   you've forgotten some \{\}'s.
 
@@ -1178,7 +1273,7 @@ keyword in the \rsrc\ file which controls the discussed warning.
 
   Some \LaTeX\ commands will be interpreted by \chktex; however, some
   of them are sensible to errors in the \LaTeX\ source. Most notably,
-  the \verb@\@\verb@input@ command relies on that the input file exists\dots
+  the \verb@\@\verb@input@ command requires that the input file exist\dots
 
 \end{errdesc}
 
@@ -1396,20 +1491,80 @@ keyword in the \rsrc\ file which controls the discussed warning.
   this and similar errors.
 \end{errdesc}
 
+\Keyword{UserWarnRegex}
+\begin{errdesc}{User Regex:\ \%s.}
+  A pattern you've specified using \texttt{UserWarnRegex} in the \rsrc\ file,
+  has been found.  See also warning~20 which allows specification of simple
+  string matching.
+
+  Depending on how \chktex\ was configured, you can use either PCRE regular
+  expressions, POSIX extended regular expressions, or none at all.
+  A warning will be issued if \chktex\ was built without regular expression
+  support, but you try to use one.
+
+  By default the matching portion of the line is printed to help distinguish
+  between user specified regular expressions.  However, if the regular
+  expression begins with a PCRE comment (which has a syntax of
+  \verb+(?#+~\dots~\verb+)+), then that comment will be printed instead.
+  This can be used to remind yourself why you were searching for the problem
+  or how to fix it.  This applies even if POSIX regular expressions are used
+  since \chktex\ itself parses a single initial PCRE-style comment.
+
+  \emph{Note:} If a regular expression (not a comment) starts with
+  \texttt{PCRE:} or \texttt{POSIX:} it will be used only if support for that
+  regular expression engine has been compiled in.  It is primarily meant to
+  make testing easier but, can be used to allow better regular expressions
+  if PCRE is available.  If you want a regular expression that starts with
+  \texttt{PCRE:} or \texttt{POSIX:} then you can enclose one of the
+  characters in brackets like \texttt{[P]CRE:}.
+
+  An example, included in the \rsrc\ file, is given below.  Remember that you
+  have to escape (with~\verb+!+) spaces and \verb+#+ as well as a few other
+  characters.  One should always use \verb+\nmid+ instead of \verb+\not\mid+
+  because the results are much better.
+  \begin{errexam}
+    \verb+\\not! *(\||\\mid)+\\*
+    \verb+User Regex: \not\mid.+\\*
+  \end{errexam}
+  or with an initial comment
+  \begin{errexam}
+    \verb+(?!#Always! use! \nmid)\\not! *(\||\\mid)+\\*
+    \verb+User Regex: Always use \nmid.+
+  \end{errexam}
+
+  You can use \verb+% chktex 44+ to suppress user regular expression
+  warnings on a given line, but this is often undesirable since all such
+  warnings are suppressed this way.  For this reason you can ``name'' user
+  regular expression warnings with negative numbers.  For example
+  \verb+% chktex 4+ will suppress the system warning number 4, but
+  \verb+% chktex -4+ will suppress the user regular expression warning
+  number 4.  Since one might wish to add, remove, or rearrange user warnings
+  in the \rsrc\ file, you must explicitly name particular warnings rather
+  than relying on position in that file.
+
+  In order to name one, include an initial PCRE-style comment with the first
+  characters being a number (positive or negative---the absolute value will
+  be used).  The numbers are limited by the number of bits in a \texttt{long},
+  usually giving 1--63 as possible names.  You can give more than one regular
+  expression the same name, and suppressing that name will suppress all
+  regular expressions with that name.
+
+  Using the example from before, all of the following will be suppressed with
+  \verb+% chktex -4+.  Note that the name \emph{will} be printed as written
+  so that you know which number to suppress.
+  \begin{errexam}
+    \verb+(?!#4:Always! use! \nmid)\\not! *(\||\\mid)+\\*
+    \verb+(?!#-4Always! use! \nmid)\\not! *(\||\\mid)+\\*
+    \verb+(?!#-4! Always! use! \nmid)\\not! *(\||\\mid)+\\*
+  \end{errexam}
+\end{errdesc}
+
 \section{Future plans}
 
 In a somewhat prioritized sequence, this is what I'd like to put into the
 program --- if I have the time.
 
 \begin{itemize}
-\item Do a final fix for maths mode. Currently, \chktex\ doesn't
-  recognize constructions like
-  \verb@$$a+b\text{for $a \leq 0$}$$@, i.e.\ embedded math mode.
-
-\item Support for regular expressions as user patterns. I'll do it at
-  once I get the GNU \Cmd{rx} package up and running (it doesn't
-  produce correct include files).
-
 \item De-linearize the checker. Currently, it works on a line-by-line
   basis, in most respects, at least. I hope to be able to remove this
   barrier; as this will reduce the amount of false warnings
@@ -1475,25 +1630,7 @@ I would like to receive. The following ideas are given:
   appreciated (and included). Look at the \verb@deweb@ script to see
   what I mean.
 
-\item Arexx interfaces for other editors are also welcomed; these
-  should be rather fast to write.  They should to the following:
-  \begin{enumerate}
-  \item Get the filename of the active file.
-  \item If possible, save the file to disk if there has been any
-    changes.
-  \item Call the program \Cmd{ChkTeX.rexx} with the filename as the
-    only parameter.
-  \end{enumerate}
-
-\item If somebody out there actually possesses (and uses) GoldED, it
-  would be nice if they checked whether the ARexx script included
-  actually work.  If not, please send me a fixed copy; perhaps also
-  one which supports point 2 above, too. If it does work, then please
-  tell me so, so I can remove this item.
-
-  I don't have GoldEd in my possession; the script was just modelled
-  after Juergen Zeschky's, (\texttt{<juergen@sokrates.nbg.de>})
-  $\mbox{PGP}\leftrightarrow\mbox{GoldED}$ interface.
+\item Interfaces for other editors are also welcomed.
 
 \item If you update the \rsrc\ file in anyway that is not strictly
   local, I would appreciate to receive your updated version.
@@ -1508,11 +1645,6 @@ thus receive eternal glory and appreciation.
 
 \subsection{Caps and stuff}
 
-This program uses the \Cmd{getopt()} routine, as supplied from GNU\@.
-The source included in this distribution has been modified slightly.
-To make the use of C2LOCAL easier, portions which were
-\verb@#ifdef@'ed out, have now been commented out.
-
 Where trademarks have been used, the author is aware of that they
 belong to someone, and has tried to stick to the original caps.
 
@@ -1588,7 +1720,7 @@ The author wishes to thank the following people (in alphabetical order):
   In addition, he sent me a huge list of 238 common English
   abbreviations, for inclusion in the \rsrc\ file! Together with the
   enhanced abbreviation recognizer, I do now believe most
-  abbreviations should be catched\dots
+  abbreviations should be caught\dots
 
   Finally, he has also given me valuable hints for improving the
   program's outputting routine, and given me lots of suggestions for
@@ -1599,6 +1731,14 @@ The author wishes to thank the following people (in alphabetical order):
   ready-to-yank code patches. The original port didn't respect all
   the peculiarities of the MS-DOS file-system, unfortunately.
 
+  \Name{Antonio DiCesare}{dicesare@vodafone.it}
+  He provided many feature requests and bug reports for the 1.7.1
+  version making it a much better release than it would have otherwise
+  been.  He also helped expand several keywords in the \rsrc\ file.
+
+  \Name{Baruch Even}{chktex@ev-en.org}
+  Maintainer of \chktex\ for about a decade.
+
   \Name{Lars Frellesen}{frelle@math-tech.dk} Sent a few bug reports
   regarding the filtering of messages. He has also helped me to
   expand the \Cmd{SILENT} keyword in the \rsrc\ file.
@@ -1676,8 +1816,8 @@ Since the original author is unreachable, the maintainer these days is:
 \begin{samepage}
 %endlatex
   \begin{quote}
-    Baruch Even     \\
-    E-mail: \texttt{<chktex@ev-en.org>}
+    Ivan Andrus     \\
+    E-mail: \texttt{<darthandrus@gmail.com>}
   \end{quote}
 %latex
 \end{samepage}
@@ -1688,3 +1828,9 @@ Have fun.
 
 \end{document}
 
+% Rudimentary support for AUCTeX.
+% The "Make" target is my own.
+% Local Variables:
+% TeX-command-default: "Make"
+% TeX-master: "ChkTeX.tex"
+% End:
diff --git a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.texrc b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.texrc
index e990c71d1be..e990c71d1be 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/ChkTeX.texrc
+++ b/Build/source/texk/chktex/chktex-1.7.1/ChkTeX.texrc
diff --git a/Build/source/texk/chktex/chktex-1.6.6/FindErrs.c b/Build/source/texk/chktex/chktex-1.7.1/FindErrs.c
index 45a6b02bfe5..4cfc7fa509b 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/FindErrs.c
+++ b/Build/source/texk/chktex/chktex-1.7.1/FindErrs.c
@@ -33,6 +33,31 @@
 #include "Utility.h"
 #include "Resource.h"
 
+/* Not everyone has stpcpy() */
+static inline char *
+stpcpy(char *dest, const char *src)
+{
+    return strcpy(dest, src) + strlen(src);
+}
+
+#if HAVE_PCRE || HAVE_POSIX_ERE
+
+#if HAVE_PCRE
+#include <pcreposix.h>
+#else
+#include <regex.h>
+#endif
+
+#define REGEX_FLAGS REG_EXTENDED
+#define NUM_MATCHES 10
+#define ERROR_STRING_SIZE 100
+
+regex_t* RegexArray = NULL;
+regex_t* SilentRegex = NULL;
+int NumRegexes = 0;
+
+#endif
+
 /***************************** ERROR MESSAGES ***************************/
 
 #undef MSG
@@ -49,7 +74,10 @@ static int my_##func(int c) \
    return(func(c)); \
 }
 
-#define INUSE(c)        (LaTeXMsgs[(enum ErrNum) c].InUse == iuOK)
+#define SUPPRESSED_ON_LINE(c)  (LineSuppressions & (1LL<<c))
+
+#define INUSE(c) \
+    ((LaTeXMsgs[(enum ErrNum) c].InUse == iuOK) && !SUPPRESSED_ON_LINE(c))
 
 #define PSERR2(pos,len,err,a,b) \
     PrintError(CurStkName(&InputStack), RealBuf, pos, len, Line, err, a, b)
@@ -98,6 +126,31 @@ static const char LTX_GenPunc[] = { ',', ';', 0 };
  */
 static const char LTX_SmallPunc[] = { '.', ',', 0 };
 
+/*
+ * String used to delimit a line suppression.  This string must be
+ * followed immediately by the number of the warning to be suppressed.
+ * If more than one warning is to be suppressed, then multiple copies
+ * of LineSuppDelim+number must be used.
+ */
+const char LineSuppDelim[] = "chktex ";
+
+/*
+ * String used to delimit a file suppression.  This string must be
+ * followed immediately by the number of the warning to be suppressed.
+ * If more than one warning is to be suppressed, then multiple copies
+ * of FileSuppDelim+number must be used.
+ */
+const char FileSuppDelim[] = "chktex-file ";
+
+/*
+ * A bit field used to hold the suppressions for the current line.
+ */
+static unsigned long long LineSuppressions;
+/*
+ * A bit field used to hold the suppressions of numbered user warnings
+ * for the current line.
+ */
+static unsigned long long UserLineSuppressions;
 
 static unsigned long Line;
 
@@ -106,6 +159,7 @@ static char *LineCpy;
 static char *BufPtr;
 
 static int ItFlag = efNone;
+static int MathFlag = efNone;
 
 NEWBUF(Buf, BUFSIZ);
 NEWBUF(CmdBuffer, BUFSIZ);
@@ -258,20 +312,89 @@ static char *MakeCpy(void)
 
 static char *PreProcess(void)
 {
-    /* First, kill comments. */
-
     char *TmpPtr;
 
+    /* Reset any line suppressions  */
+
+    LineSuppressions = FileSuppressions;
+    UserLineSuppressions = UserFileSuppressions;
+
+    /* Kill comments. */
     strcpy(Buf, RealBuf);
 
     TmpPtr = Buf;
 
     while ((TmpPtr = strchr(TmpPtr, '%')))
     {
-        if (TmpPtr == Buf || TmpPtr[-1] != '\\')
+        char *EscapePtr = TmpPtr;
+        int NumBackSlashes = 0;
+        while (EscapePtr != Buf && EscapePtr[-1] == '\\')
+        {
+            ++NumBackSlashes;
+            --EscapePtr;
+        }
+
+        /* If there is an even number of backslashes, then it's a comment. */
+        if ((NumBackSlashes % 2) == 0)
         {
             PSERR(TmpPtr - Buf, 1, emComment);
             *TmpPtr = 0;
+            /* Check for line suppressions */
+            if (!NoLineSupp)
+            {
+                int error;
+                const int MaxSuppressionBits = sizeof(unsigned long long)*8-1;
+
+                /* Convert to lowercase to compare with LineSuppDelim */
+                EscapePtr = ++TmpPtr; /* move past NUL terminator */
+                while ( *EscapePtr )
+                {
+                    *EscapePtr = tolower(*EscapePtr);
+                    ++EscapePtr;
+                }
+
+                EscapePtr = TmpPtr; /* Save it for later */
+                while ((TmpPtr = strstr(TmpPtr, FileSuppDelim))) {
+                    TmpPtr += STRLEN(FileSuppDelim);
+                    error = atoi(TmpPtr);
+
+                    if (abs(error) > MaxSuppressionBits)
+                    {
+                        PrintPrgErr(pmSuppTooHigh, error, MaxSuppressionBits);
+                    }
+                    if (error > 0)
+                    {
+                        FileSuppressions |= (1LL << error);
+                        LineSuppressions |= (1LL << error);
+                    }
+                    else
+                    {
+                        UserFileSuppressions |= (1LL << (-error));
+                        UserLineSuppressions |= (1LL << (-error));
+                    }
+                }
+                TmpPtr = EscapePtr;
+
+                while ((TmpPtr = strstr(TmpPtr, LineSuppDelim))) {
+
+                    TmpPtr += STRLEN(LineSuppDelim);
+                    error = atoi(TmpPtr);
+
+                    if (abs(error) > MaxSuppressionBits)
+                    {
+                        PrintPrgErr(pmSuppTooHigh, error, MaxSuppressionBits);
+                    }
+
+                    if (error > 0)
+                    {
+                        LineSuppressions |= (1LL << error);
+                    }
+                    else
+                    {
+                        UserLineSuppressions |= (1LL << (-error));
+                    }
+                }
+            }
             break;
         }
         TmpPtr++;
@@ -416,11 +539,17 @@ static void WipeArgument(const char *Cmd, char *CmdPtr)
                 if (*TmpPtr == '[')
                     TmpPtr = GetLTXArg(TmpPtr, ArgBuffer, ']', NULL);
                 break;
+            case '(':
+                SKIP_AHEAD(TmpPtr, TmpC, LATEX_SPACE(TmpC));
+                if (*TmpPtr == '(')
+                    TmpPtr = GetLTXArg(TmpPtr, ArgBuffer, ')', NULL);
+                break;
             case '{':
                 SKIP_AHEAD(TmpPtr, TmpC, LATEX_SPACE(TmpC));
                 TmpPtr = GetLTXArg(TmpPtr, ArgBuffer, GET_TOKEN, NULL);
             case '}':
             case ']':
+            case ')':
                 break;
             default:
                 PrintPrgErr(pmWrongWipeTemp, &Cmd[strlen(Cmd) + 1]);
@@ -429,9 +558,9 @@ static void WipeArgument(const char *Cmd, char *CmdPtr)
         }
 
         if (TmpPtr)
-            strwrite(CmdPtr, VerbClear, TmpPtr - CmdPtr);
+            strwrite(CmdPtr+CmdLen, VerbClear, TmpPtr - CmdPtr - CmdLen);
         else
-            strxrep(CmdPtr, "()[]{}", *VerbClear);
+            strxrep(CmdPtr+CmdLen, "()[]{}", *VerbClear);
     }
 }
 
@@ -646,9 +775,175 @@ static void CheckRest(void)
 
     /* Search for user-specified warnings */
 
-    if (INUSE(emUserWarn))
+#if ! (HAVE_PCRE || HAVE_POSIX_ERE)
+
+    if (INUSE(emUserWarnRegex) && UserWarnRegex.Stack.Used > 0)
+    {
+        PrintPrgErr(pmNoRegExp);
+        ClearWord( &UserWarnRegex );
+    }
+    else if (INUSE(emUserWarn))
+    {
+        strcpy(TmpBuffer, Buf);
+    }
+
+#else
+
+    if (INUSE(emUserWarnRegex) && UserWarnRegex.Stack.Used > 0)
+    {
+        static char error[ERROR_STRING_SIZE];
+        static regmatch_t MatchVector[NUM_MATCHES];
+        int rc;
+        int len = strlen(TmpBuffer);
+        strcpy(TmpBuffer, Buf);
+
+        /* Compile all regular expressions if not already compiled. */
+        if ( !RegexArray && UserWarnRegex.Stack.Used > 0 )
+        {
+            RegexArray = (regex_t*)malloc( sizeof(regex_t) * UserWarnRegex.Stack.Used );
+            if (!RegexArray)
+            {
+                /* Allocation failed. */
+                PrintPrgErr(pmNoRegexMem);
+                ClearWord(&UserWarnRegex);
+                NumRegexes = 0;
+            }
+            else
+            {
+                NumRegexes = 0;
+                FORWL(Count, UserWarnRegex)
+                {
+                    char *pattern = UserWarnRegex.Stack.Data[Count];
+                    char *CommentEnd = NULL;
+
+                    /* See if it's got a special name that it goes by.
+                       Only use the comment if it's at the very beginning. */
+                    if ( strncmp(pattern,"(?#",3) == 0 )
+                    {
+                        CommentEnd = strchr(pattern, ')');
+                        /* TODO: check for PCRE/POSIX only regexes */
+                        *CommentEnd = '\0';
+                        /* We're leaking a little here, but this was never freed until exit anyway... */
+                        UserWarnRegex.Stack.Data[NumRegexes] = pattern+3;
+
+                        /* Compile past the end of the comment so that it works with POSIX too. */
+                        pattern = CommentEnd + 1;
+                    }
+
+                    /* Ignore PCRE and POSIX specific regexes.
+                     * This is mostly to make testing easier. */
+                    if ( strncmp(pattern,"PCRE:",5) == 0 )
+                    {
+                        #if HAVE_PCRE
+                        pattern += 5;
+                        #else
+                        continue;
+                        #endif
+                    }
+                    if ( strncmp(pattern,"POSIX:",6) == 0 )
+                    {
+                        #if HAVE_POSIX_ERE
+                        pattern += 6;
+                        #else
+                        continue;
+                        #endif
+                    }
+
+                    rc = regcomp((regex_t*)(&RegexArray[NumRegexes]),
+                                 pattern, REGEX_FLAGS);
+
+                    /* Compilation failed: print the error message */
+                    if (rc != 0)
+                    {
+                        /* TODO: decide whether a non-compiling regex should completely stop, or just be ignored */
+                        regerror(rc,(regex_t*)(&RegexArray[NumRegexes]),
+                                 error, ERROR_STRING_SIZE);
+                        PrintPrgErr(pmRegexCompileFailed, pattern, error);
+                    }
+                    else
+                    {
+                        if ( !CommentEnd )
+                        {
+                            ((char*)UserWarnRegex.Stack.Data[NumRegexes])[0] = '\0';
+                        }
+                        ++NumRegexes;
+                    }
+                }
+            }
+        }
+
+        for (Count = 0; Count < NumRegexes; ++Count)
+        {
+            int offset = 0;
+            char *ErrMessage = UserWarnRegex.Stack.Data[Count];
+            const int NamedWarning = strlen(ErrMessage) > 0;
+
+            while (offset < len)
+            {
+                /* Check if this warning should be suppressed. */
+                if (UserLineSuppressions != 0LL && NamedWarning)
+                {
+                    /* The warning can be named with positive or negative numbers. */
+                    int UserWarningNumber = abs(atoi(ErrMessage));
+                    if (UserLineSuppressions & (1LL << UserWarningNumber))
+                    {
+                        break;
+                    }
+                }
+
+                rc = regexec( (regex_t*)(&RegexArray[Count]), TmpBuffer+offset,
+                              NUM_MATCHES, MatchVector, 0);
+                /* Matching failed: handle error cases */
+                if (rc != 0)
+                {
+                    switch(rc)
+                    {
+                        case REG_NOMATCH:
+                            /* no match, no problem */
+                            break;
+                        default:
+                            regerror(rc, (regex_t*)(&RegexArray[Count]),
+                                     error, ERROR_STRING_SIZE);
+                            PrintPrgErr(pmRegexMatchingError, error);
+                            break;
+                    }
+
+                    offset = len; /* break out of loop */
+                }
+                else
+                {
+#define MATCH (MatchVector[0])
+                    if ( NamedWarning )
+                    {
+                        /* User specified error message */
+                        PSERR2(offset + MATCH.rm_so, MATCH.rm_eo - MATCH.rm_so,
+                               emUserWarnRegex,
+                               strlen(ErrMessage), ErrMessage);
+                    }
+                    else
+                    {
+                        /* Default -- show the match */
+                        PSERR2(offset + MATCH.rm_so, MATCH.rm_eo - MATCH.rm_so,
+                               emUserWarnRegex,
+                               MATCH.rm_eo - MATCH.rm_so,
+                               TmpBuffer + offset + MATCH.rm_so);
+                    }
+                    offset += MATCH.rm_eo;
+#undef MATCH
+                }
+            }
+        }
+    }
+    else if (INUSE(emUserWarn))
     {
         strcpy(TmpBuffer, Buf);
+    }
+
+#endif
+
+
+    if (INUSE(emUserWarn))
+    {
         FORWL(Count, UserWarn)
         {
             for (UsrPtr = TmpBuffer;
@@ -656,11 +951,10 @@ static void CheckRest(void)
                  UsrPtr++)
             {
                 CmdLen = strlen(UserWarn.Stack.Data[Count]);
-                PSERR(UsrPtr - TmpBuffer, CmdLen, emUserWarn);
+                PSERRA(UsrPtr - TmpBuffer, CmdLen, emUserWarn, UserWarn.Stack.Data[Count]);
             }
         }
 
-
         strlwr(TmpBuffer);
 
         FORWL(Count, UserWarnCase)
@@ -670,7 +964,7 @@ static void CheckRest(void)
                  UsrPtr++)
             {
                 CmdLen = strlen(UserWarnCase.Stack.Data[Count]);
-                PSERR(UsrPtr - TmpBuffer, CmdLen, emUserWarn);
+                PSERRA(UsrPtr - TmpBuffer, CmdLen, emUserWarn, UserWarnCase.Stack.Data[Count]);
             }
         }
     }
@@ -749,6 +1043,7 @@ static void HandleBracket(int Char)
             if ((ei = PopErr(&CharStack)))
             {
                 Match = MatchBracket(*(ei->Data));
+                /* Return italics to proper state */
                 if (ei->Flags & efNoItal)
                 {
                     if (ItState == itOn)
@@ -756,7 +1051,13 @@ static void HandleBracket(int Char)
                         TmpPtr = BufPtr;
                         SKIP_AHEAD(TmpPtr, TmpC, TmpC == '}');
 
-                        if (!strchr(LTX_SmallPunc, *TmpPtr))
+                        /* If the next character is a period or comma,
+                         * or the last character is, then it's not an
+                         * error. */
+                        /* Checking 2 characters back seems dangerous,
+                         * but it's already done in CheckDash. */
+                        if ( !strchr(LTX_SmallPunc, *TmpPtr) &&
+                             !strchr(LTX_SmallPunc, *(TmpPtr-2)) )
                             HERE(1, emNoItFound);
                     }
 
@@ -764,6 +1065,17 @@ static void HandleBracket(int Char)
                 }
                 else if (ei->Flags & efItal)
                     ItState = TRUE;
+
+                /* Same for math mode */
+                if (ei->Flags & efMath)
+                {
+                    MathMode = 1;
+                }
+                else if (ei->Flags & efNoMath)
+                {
+                    MathMode = 0;
+                }
+
                 FreeErrInfo(ei);
             }
             else
@@ -793,12 +1105,22 @@ static void HandleBracket(int Char)
                     switch (ItFlag)
                     {
                     default:
-                        ei->Flags = ItFlag;
+                        ei->Flags |= ItFlag;
                         ItFlag = efNone;
                         break;
                     case efNone:
                         ei->Flags |= ItState ? efItal : efNoItal;
                     }
+
+                    switch (MathFlag)
+                    {
+                    default:
+                        ei->Flags |= MathFlag;
+                        MathFlag = efNone;
+                        break;
+                    case efNone:
+                        ei->Flags |= MathMode ? efMath : efNoMath;
+                    }
                 }
             }
 
@@ -809,6 +1131,95 @@ static void HandleBracket(int Char)
 }
 
 
+/*
+ * Checks to see if CmdBuffer matches any of the words in Silent, or
+ * any of the regular expressions in SilentCase.
+ *
+ */
+
+int CheckSilentRegex(void)
+{
+
+#if ! (HAVE_PCRE || HAVE_POSIX_ERE)
+
+    return HasWord(CmdBuffer, &Silent);
+
+#else
+
+    static char error[ERROR_STRING_SIZE];
+    char *pattern;
+    char *tmp;
+    int i;
+    int rc;
+    int len = 4;                /* Enough for the (?:) */
+
+    /* Initialize regular expression */
+    if (INUSE(emSpaceTerm) && SilentCase.Stack.Used > 0)
+    {
+        /* Find the total length we need */
+        /* There is 1 for | and the final for null terminator */
+        FORWL(i, SilentCase)
+        {
+            len += strlen( SilentCase.Stack.Data[i] ) + 1;
+        }
+
+        /* (A|B|...) */
+        tmp = (pattern = (char*)malloc( sizeof(char) * len ));
+
+        #if HAVE_PCRE
+        tmp = stpcpy(tmp,"(?:");
+        #else
+        tmp = stpcpy(tmp,"(");
+        #endif
+
+        FORWL(i, SilentCase)
+        {
+            tmp = stpcpy(tmp, SilentCase.Stack.Data[i]);
+            *tmp++ = '|';
+        }
+        tmp = stpcpy(--tmp, ")");
+
+        SilentRegex = malloc( sizeof(regex_t) );
+        rc = regcomp(SilentRegex, pattern, REGEX_FLAGS);
+
+        /* Compilation failed: print the error message */
+        if (rc != 0)
+        {
+            regerror(rc, SilentRegex, error, ERROR_STRING_SIZE);
+            PrintPrgErr(pmRegexCompileFailed, pattern, error);
+            SilentRegex = NULL;
+        }
+        /* Ensure we won't initialize it again */
+        SilentCase.Stack.Used = 0;
+        free(pattern);
+    }
+
+    /* Check against the normal */
+    if ( HasWord(CmdBuffer, &Silent) )
+        return 1;
+    if (!SilentRegex)
+        return 0;
+
+    /* Check against the regexes */
+    rc = regexec(SilentRegex, CmdBuffer, 0, NULL, 0);
+    if (rc == 0)
+        return 1;
+
+    /* Matching failed: handle error cases */
+    switch(rc)
+    {
+        case REG_NOMATCH:
+            return 0;
+            break;
+        default:
+            regerror(rc, SilentRegex, error, ERROR_STRING_SIZE);
+            PrintPrgErr(pmRegexMatchingError, error);
+            break;
+    }
+    return 0;
+
+#endif
+}
 
 /*
  * Searches the `Buf' for possible errors, and prints the errors. `Line'
@@ -974,10 +1385,10 @@ int FindErr(const char *_RealBuf, const unsigned long _Line)
                     HEREA(3, emEllipsis, cTmpPtr);
                 }
 
-                /* Regexp: "([^A-Z@.])\.[.!?:;]*\s+[a-z]" */
+                /* Regexp: "([^A-Z@.])\.[.!?:]*\s+[a-z]" */
 
                 TmpPtr = BufPtr;
-                SKIP_AHEAD(TmpPtr, TmpC, strchr(LTX_GenPunc, TmpC));
+                SKIP_AHEAD(TmpPtr, TmpC, strchr(LTX_EosPunc, TmpC));
                 if (LATEX_SPACE(*TmpPtr))
                 {
                     if (!isupper((unsigned char)*PrePtr) && (*PrePtr != '@') &&
@@ -1161,7 +1572,7 @@ int FindErr(const char *_RealBuf, const unsigned long _Line)
                 }
 
                 if (LATEX_SPACE(*BufPtr) && !MathMode &&
-                    (!HasWord(CmdBuffer, &Silent)) &&
+                    !CheckSilentRegex() &&
                     (strlen(CmdBuffer) != 2))
                 {
                     PSERR(BufPtr - Buf, 1, emSpaceTerm);
@@ -1224,6 +1635,7 @@ int FindErr(const char *_RealBuf, const unsigned long _Line)
         {
             CheckRest();
         }
+
     }
 
     return (TRUE);
@@ -1297,7 +1709,8 @@ void PrintStatus(unsigned long Lines)
     {
         Transit(stderr, ErrPrint, "error%s printed; ");
         Transit(stderr, WarnPrint, "warning%s printed; ");
-        Transit(stderr, UserSupp, "user suppressed warning%s printed.\n");
+        Transit(stderr, UserSupp, "user suppressed warning%s; ");
+        Transit(stderr, LineSupp, "line suppressed warning%s.\n");
     }
 }
 
@@ -1344,7 +1757,11 @@ PrintError(const char *File, const char *String,
         switch (LaTeXMsgs[Error].InUse)
         {
         case iuOK:
-            do
+            if (SUPPRESSED_ON_LINE(Error))
+            {
+                LineSupp++;
+            }
+            else
             {
                 Context = LaTeXMsgs[Error].Context;
 
@@ -1453,7 +1870,6 @@ PrintError(const char *File, const char *String,
                 }
                 fputs(LastNorm, OutputFile);
             }
-            while (FALSE);
             break;
         case iuNotUser:
             UserSupp++;
@@ -1480,8 +1896,7 @@ static enum ErrNum PerformCommand(const char *Cmd, char *Arg)
         AtLetter = TRUE;
     else if (!strcmp(Cmd, "\\makeatother"))
         AtLetter = FALSE;
-    else if (InputFiles &&
-             !(strcmp(Cmd, "\\input") && strcmp(Cmd, "\\include")))
+    else if (InputFiles && !(strcmp(Cmd, "\\input") && strcmp(Cmd, "\\include")))
     {
         SKIP_AHEAD(Arg, TmpC, LATEX_SPACE(TmpC));
         if (*Arg == '{')        /* } */
@@ -1497,6 +1912,24 @@ static enum ErrNum PerformCommand(const char *Cmd, char *Arg)
     }
     else if (HasWord(Cmd, &Primitives))
         en = emTeXPrim;
+    else if (HasWord(Cmd, &MathCmd))
+    {
+        SKIP_AHEAD(Arg, TmpC, LATEX_SPACE(TmpC));
+        if (*Arg == '{')
+        {
+            MathFlag = MathMode ? efMath : efNoMath;
+            MathMode = 1;
+        }
+    }
+    else if (HasWord(Cmd, &TextCmd))
+    {
+        SKIP_AHEAD(Arg, TmpC, LATEX_SPACE(TmpC));
+        if (*Arg == '{')
+        {
+            MathFlag = MathMode ? efMath : efNoMath;
+            MathMode = 0;
+        }
+    }
     else if (*Cmd == '\\')
     {
         /* Quicker check of single lettered commands. */
diff --git a/Build/source/texk/chktex/chktex-1.6.6/FindErrs.h b/Build/source/texk/chktex/chktex-1.7.1/FindErrs.h
index 47f98c5e6aa..c938a365928 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/FindErrs.h
+++ b/Build/source/texk/chktex/chktex-1.7.1/FindErrs.h
@@ -76,7 +76,7 @@
  MSG(emUseOtherQuote, etWarn, iuOK, ctNone,\
      "Use \"'\" (ASCII 39) instead  of \"´\" (ASCII 180).")\
  MSG(emUserWarn, etWarn, iuOK, ctNone,\
-     "User-specified pattern found.")\
+     "User-specified pattern found: %s.")\
  MSG(emNotIntended, etWarn, iuNotSys, ctNone,\
      "This command might not be intended.")\
  MSG(emComment, etMsg, iuNotSys, ctNone,\
@@ -122,7 +122,9 @@
  MSG(emRemPSSpace, etWarn, iuOK, ctOutMath,\
      "You should remove spaces in front of `%s'") \
  MSG(emNoCharMean, etWarn, iuOK, ctNone,\
-     "`%s' is normally not followed by `%c'.")
+     "`%s' is normally not followed by `%c'.")\
+ MSG(emUserWarnRegex, etWarn, iuOK, ctNone,\
+     "User Regex: %.*s.")
 
 #undef MSG
 #define MSG(num, type, inuse, ctxt, text) num,
@@ -185,6 +187,7 @@ extern struct ErrMsg LaTeXMsgs[emMaxFault + 1];
 
 extern char *OutputFormat;
 
+int CheckSilentRegex(void);
 int FindErr(const char *, const unsigned long);
 void PrintError(const char *, const char *, const long, const long,
                 const long, const enum ErrNum, ...);
diff --git a/Build/source/texk/chktex/chktex-1.6.6/MakeHTML.pl b/Build/source/texk/chktex/chktex-1.7.1/MakeHTML.pl
index 6bdbadcf127..6bdbadcf127 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/MakeHTML.pl
+++ b/Build/source/texk/chktex/chktex-1.7.1/MakeHTML.pl
diff --git a/Build/source/texk/chktex/chktex-1.6.6/Makefile.in b/Build/source/texk/chktex/chktex-1.7.1/Makefile.in
index ed28c2d92a2..ee8dda3eead 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/Makefile.in
+++ b/Build/source/texk/chktex/chktex-1.7.1/Makefile.in
@@ -85,7 +85,7 @@ SOURCEFILES=$(CSOURCES) $(wildcard $(CSOURCES:.c=.h)) types.h
 
 DISTFILES=$(EXTRA_DIST) $(SOURCEFILES)
 
-all: chktex 
+all: chktex
 
 DISTDIR:=chktex-@PACKAGE_VERSION@
 dist: $(DISTDIR).tar.gz
@@ -126,23 +126,26 @@ OBJS= ChkTeX.o FindErrs.o OpSys.o Resource.o Utility.o
 
 MAKETEST= (builddir=`pwd` ; cd $(srcdir) ; $${builddir}/chktex -mall -r -g0 -lchktexrc -v5 Test.tex)
 
-$(srcdir)/Test.out:
+$(srcdir)/Test.out: $(srcdir)/Test.tex
 	-rm -f $(srcdir)/Test.out
-	$(MAKETEST) 1> $(srcdir)/Test.out 
+	@echo ""
+	@echo "***Warning: creating Test.out***"
+	@echo ""
+	$(MAKETEST) 1> $(srcdir)/Test.out
 
-check: chktex
+check: chktex $(srcdir)/Test.out
 	@echo ">>> Testing that checking algorithms work correctly..."
 	@-rm -f chktest
-	$(MAKETEST) 1> chktest  
+	$(MAKETEST) 1> chktest
 	@if cmp -s chktest $(srcdir)/Test.out; then \
-	echo ">>> OK!"; \
-	rm -f chktest; \
+		echo ">>> OK!"; \
+		rm -f chktest; \
 	else \
-	echo "***WARNING***"; \
-	echo "Problems when checking compilation. This may or may not"; \
-	echo "be a problem; anyway, I'm giving you a diff from what the"; \
-	echo "results were *supposed* to be..."; \
-	diff -u chktest $(srcdir)/Test.out; \
+		echo "***WARNING***"; \
+		echo "Problems when checking compilation. This may or may not"; \
+		echo "be a problem; anyway, I'm giving you a diff from what the"; \
+		echo "results were *supposed* to be..."; \
+		diff -u $(srcdir)/Test.out chktest; \
 	fi
 
 
@@ -201,6 +204,8 @@ maintainer-clean: distclean
 
 dvi: ChkTeX.dvi
 
+pdf: ChkTeX.pdf
+
 ifneq ($(LATEX2HTML),)
 html: ChkTeX.tex MakeHTML.pl
 	-rm -r HTML
diff --git a/Build/source/texk/chktex/chktex-1.6.6/NEWS b/Build/source/texk/chktex/chktex-1.7.1/NEWS
index b525e1983d8..895b8e9c3ed 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/NEWS
+++ b/Build/source/texk/chktex/chktex-1.7.1/NEWS
@@ -1,5 +1,28 @@
-Development of ChkTeX is now in a maintainance mode. All versions
-after 1.6 are essentially bug fixes.
+Development of ChkTeX is now in a maintainance mode.  All versions
+1.6.x are essentially bug fixes.  Version 1.7 added some new features.
+
+1.7.1 (2012-08-22), released by Ivan Andrus <darthandrus@gmail.com>
+
+  * Improvements for TeX Live and CTAN
+  * Fixed bug when checking for interword spacing
+  * Added warning when a file has lines that are too long which can cause problems
+  * Added ability to suppress user regular expression warnings by "naming" them
+  * Added ability to suppress warnings for the rest of the file
+  * Allow using PCRE or POSIX ERE or neither (at configure time).
+      Regular expressions can be marked as PCRE or POSIX only.
+  * Allow () to specify an optional argument in WipeArg to support \cmidrule[](){}
+  * Allow regular expressions for Silent keyword, specified in [] for "case insensitive"
+  * Added warning about \hline and vertical rules in tabular environments
+  * I changed user warnings to be post WipeArg (like they were pre
+      1.7.0).  I had changed them in 1.7.0 to be pre WipeArg so that I
+      could match things like \label{...}, but this caused many false
+      positives by matching in comments, etc.
+
+1.7.0 (2012-05-28), released by Ivan Andrus <darthandrus@gmail.com>
+
+  * Added support for user defined regular expression based warnings
+  * Added support for macros like \ensuremath and \text
+  * Added support for suppressing messages on a single line
 
 1.6.6 (2012-04-07), released by Ivan Andrus <darthandrus@gmail.com>
 
diff --git a/Build/source/texk/chktex/chktex-1.6.6/OpSys.c b/Build/source/texk/chktex/chktex-1.7.1/OpSys.c
index d2891b08581..d2891b08581 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/OpSys.c
+++ b/Build/source/texk/chktex/chktex-1.7.1/OpSys.c
diff --git a/Build/source/texk/chktex/chktex-1.6.6/OpSys.h b/Build/source/texk/chktex/chktex-1.7.1/OpSys.h
index 7ce3f1b5270..7ce3f1b5270 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/OpSys.h
+++ b/Build/source/texk/chktex/chktex-1.7.1/OpSys.h
diff --git a/Build/source/texk/chktex/chktex-1.7.1/README b/Build/source/texk/chktex/chktex-1.7.1/README
new file mode 100644
index 00000000000..ba098014666
--- /dev/null
+++ b/Build/source/texk/chktex/chktex-1.7.1/README
@@ -0,0 +1,22 @@
+ChkTeX
+======
+
+ChkTeX is a tool to check for common errors in LaTeX files.  It also
+supports checking CWEB files (uses a perl5 script).  It is highly
+customizable allowing you turn off any warnings you don't like, as
+well as add your own warnings.  It works easily with Emacs and AUCTeX,
+but should also be easy to interface with other editors.  If you have
+interfaced ChkTeX with another editor, please contribute how you did
+it.
+
+It is important to remember that ChkTeX is only intended as a *guide*
+to fixing faults.  It is by no means always correct.  This means that
+correct LaTeX code may produce errors in ChkTeX, and vice versa:
+incorrect LaTeX code may pass silently through.  If you have ideas for
+new warnings or ways in which current warnings could be improved,
+please report them on the
+[bug tracker](https://savannah.nongnu.org/bugs/?group=chktex).
+
+For complete documentation see [the manual](http://www.nongnu.org/chktex/ChkTeX.pdf).
+
+ChkTeX is released under the GNU Public License version 2 or greater.
diff --git a/Build/source/texk/chktex/chktex-1.6.6/Resource.c b/Build/source/texk/chktex/chktex-1.7.1/Resource.c
index c30e73acd6d..68a4b3196e5 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/Resource.c
+++ b/Build/source/texk/chktex/chktex-1.7.1/Resource.c
@@ -41,7 +41,7 @@ RESOURCE_INFO
 #undef LCASE
 #undef LNEMPTY
 #undef LIST
-    struct KeyWord
+struct KeyWord
 {
     const char *Name;
     const char **String;        /* Keyword = item */
@@ -79,15 +79,15 @@ struct KeyWord Keys[] = {
 
 #undef BIT
 #define BIT BITDEF1
-TOKENBITS(Token_BIT)
+TOKENBITS(Token_BIT);
 #undef BIT
 #define BIT BITDEF2
-    TOKENBITS(Token)
-     static enum Token Expect;
-     static unsigned long RsrcLine;
+TOKENBITS(Token);
+static enum Token Expect;
+static unsigned long RsrcLine;
 
-     static enum Token ReadWord(char *, FILE *);
-     static char MapChars(char **String);
+static enum Token ReadWord(char *, FILE *);
+static char MapChars(char **String);
 
 
 
@@ -104,7 +104,7 @@ TOKENBITS(Token_BIT)
  * Returns whether the attempt was a successful one.
  */
 
-     int ReadRC(const char *Filename)
+int ReadRC(const char *Filename)
 {
     const char *String = NULL;
     int Success = FALSE;
diff --git a/Build/source/texk/chktex/chktex-1.6.6/Resource.h b/Build/source/texk/chktex/chktex-1.7.1/Resource.h
index 7f23333d3ff..73b5c8ac60a 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/Resource.h
+++ b/Build/source/texk/chktex/chktex-1.7.1/Resource.h
@@ -36,13 +36,14 @@
 #define CMNT    '#'             /* Char used as comment                         */
 
 #define RESOURCE_INFO \
-  LIST(Silent)     LIST(Linker)     LIST(IJAccent) LIST(Italic)\
+  LCASE(Silent)    LIST(Linker)     LIST(IJAccent) LIST(Italic)\
   LIST(ItalCmd)    LIST(PostLink)   LIST(WipeArg)  LIST(VerbEnvir)\
-  LIST(MathEnvir)  LIST(MathRoman)  LIST(HyphDash) LIST(NumDash)\
-  LIST(WordDash)   LIST(CenterDots) LIST(LowDots)  LIST(OutFormat)\
+  LIST(MathEnvir)  LIST(MathCmd)    LIST(TextCmd)  LIST(MathRoman)\
+  LIST(HyphDash)   LIST(NumDash)    LIST(WordDash)\
+  LIST(CenterDots) LIST(LowDots)    LIST(OutFormat)\
   LIST(Primitives) LIST(NotPreSpaced) LIST(NonItalic) LIST(NoCharNext)\
   LNEMPTY(CmdLine) LNEMPTY(TeXInputs)\
-  LCASE(Abbrev)    LCASE(UserWarn)\
+  LCASE(Abbrev)    LCASE(UserWarn)  LIST(UserWarnRegex)\
   KEY(VerbClear, "|") KEY(QuoteStyle, "Traditional")  KEY(TabSize, "8")
 
 #define LIST(a) extern struct WordList a;
diff --git a/Build/source/texk/chktex/chktex-1.6.6/Test.out b/Build/source/texk/chktex/chktex-1.7.1/Test.out
index 5d31418f3f3..5bea0174f04 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/Test.out
+++ b/Build/source/texk/chktex/chktex-1.7.1/Test.out
@@ -182,14 +182,26 @@ Message 22 in Test.tex: Comment displayed.
 % Warning 12  
 ^
 Message 12 in Test.tex: Interword spacing (`\ ') should perhaps be used.
-1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar  
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george  
     ^
 Message 12 in Test.tex: Interword spacing (`\ ') should perhaps be used.
-1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar  
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george  
                     ^
 Message 12 in Test.tex: Interword spacing (`\ ') should perhaps be used.
-1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar  
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george  
                                     ^
+Message 12 in Test.tex: Interword spacing (`\ ') should perhaps be used.
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george  
+                                                           ^
+Message 12 in Test.tex: Interword spacing (`\ ') should perhaps be used.
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george  
+                                                                 ^
+Message 12 in Test.tex: Interword spacing (`\ ') should perhaps be used.
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george  
+                                                                         ^
+Message 12 in Test.tex: Interword spacing (`\ ') should perhaps be used.
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george  
+                                                                                 ^
 Message 22 in Test.tex: Comment displayed.
 % Warning 13  
 ^
@@ -223,10 +235,13 @@ Is this an "example", or is it an ´example´.
 Message 22 in Test.tex: Comment displayed.
 % Warning 20  
 ^
-Message 20 in Test.tex: User-specified pattern found.
+Message 20 in Test.tex: User-specified pattern found: \unknown.
 That bug is \unknown\ to me.  
             ^^^^^^^^
 Message 22 in Test.tex: Comment displayed.
+% That bug is \unknown\ to me.  
+^
+Message 22 in Test.tex: Comment displayed.
 % Warning 21  
 ^
 Message 21 in Test.tex: This command might not be intended.
@@ -272,7 +287,7 @@ Message 11 in input.tex: You should use \ldots to achieve an ellipsis.
 \this is a test of whether the file is actually inputted...  
                                                         ^^^
 Message 22 in Test.tex: Comment displayed.
-% Warning 29   
+% Warning 29  
 ^
 Message 29 in Test.tex: $\times$ may look prettier here.
 The program opens a screen sized 640x200 pixels  
@@ -323,31 +338,31 @@ Message 22 in Test.tex: Comment displayed.
 % Warning 36-37  
 ^
 Message 36 in Test.tex: You should put a space in front of parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
     ^
 Message 37 in Test.tex: You should avoid spaces after parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
      ^
 Message 36 in Test.tex: You should put a space in front of parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
                 ^
 Message 37 in Test.tex: You should avoid spaces after parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
                  ^
 Message 37 in Test.tex: You should avoid spaces in front of parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
                             ^
 Message 36 in Test.tex: You should put a space in front of parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
                                            ^
 Message 37 in Test.tex: You should avoid spaces after parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
                                             ^
 Message 37 in Test.tex: You should avoid spaces in front of parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
                                                     ^
 Message 36 in Test.tex: You should put a space after parenthesis.
-This( an example( Nuff said )), illustrates( ``my'' )point.   
+This( an example( Nuff said )), illustrates( ``my'' )point.  
                                                      ^
 Message 22 in Test.tex: Comment displayed.
 % Warning 38  
@@ -386,6 +401,78 @@ Message 42 in Test.tex: You should remove spaces in front of `\footnote'
 This is a footnote \footnote{foo}.  
                   ^
 Message 22 in Test.tex: Comment displayed.
+% Warning 43  
+^
+Message 43 in Test.tex: `\left' is normally not followed by `{'.
+Here is a mistake $\left{x\right}$.  
+                   ^^^^^
+Message 43 in Test.tex: `\right' is normally not followed by `}'.
+Here is a mistake $\left{x\right}$.  
+                          ^^^^^^
+Message 21 in Test.tex: This command might not be intended.
+This one triggers warning 22 $\left\{x\right\}$.  
+                                   ^^
+Message 21 in Test.tex: This command might not be intended.
+This one triggers warning 22 $\left\{x\right\}$.  
+                                            ^^
+Message 22 in Test.tex: Comment displayed.
+% Warning 44 -- user regex -- default message  
+^
+Message 44 in Test.tex: User Regex:  intro..
+You should always write a good intro.  
+                              ^^^^^^^
+Message 22 in Test.tex: Comment displayed.
+% Warning 44 -- user regex -- user message  
+^
+Message 44 in Test.tex: User Regex: Always use \nmid.
+For every $p\not|n$ you have an ugly prime which doesn't divide $n$.  
+            ^^^^^
+Message 22 in Test.tex: Comment displayed.
+% Math mode check  
+^
+Message 35 in Test.tex: You should perhaps use `\sin' instead.
+\ensuremath{sin x\text{is not the same as sin x, but is the same as $sin x$}}  
+            ^^^
+Message 35 in Test.tex: You should perhaps use `\sin' instead.
+\ensuremath{sin x\text{is not the same as sin x, but is the same as $sin x$}}  
+                                                                     ^^^
+Message 36 in Test.tex: You should put a space in front of parenthesis.
+Also, $x(3)\text{ is not x(3) but it is $x(3)$}$  
+                          ^
+Message 22 in Test.tex: Comment displayed.
+This is\\% a comment. Nothing here should be checked(right)?  
+         ^
+Message 36 in Test.tex: You should put a space in front of parenthesis.
+But this is not a \% comment, so we should find this error(right)?  
+                                                          ^
+Message 22 in Test.tex: Comment displayed.
+Here(on this line only)is a warning $sin(x)$ suppressed. % chktex 36 chktex 35  
+                                                         ^
+Message 22 in Test.tex: Comment displayed.
+Here(on this line only)is a warning $sin(x)$ suppressed. % CHKTEX 35 36  
+                                                         ^
+Message 36 in Test.tex: You should put a space in front of parenthesis.
+Here(on this line only)is a warning $sin(x)$ suppressed. % CHKTEX 35 36  
+    ^
+Message 36 in Test.tex: You should put a space after parenthesis.
+Here(on this line only)is a warning $sin(x)$ suppressed. % CHKTEX 35 36  
+                       ^
+Message 44 in Test.tex: User Regex: 1:Capitalize before references.
+In section~\ref{sec:3} we have a warning.  
+  ^^^^^^^^^^^^^
+Message 22 in Test.tex: Comment displayed.
+In section~\ref{sec:4} it is suppressed. % chktex -1  
+                                         ^
+Message 22 in Test.tex: Comment displayed.
+% In section~\ref{sec:5} we don't have a warning.  
+^
+Message 44 in Test.tex: User Regex: -2:Vertical rules in tables are ugly.
+\begin{tabular*}{1.0\linewidth}[h]{|c|cc|}  
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Message 44 in Test.tex: User Regex: -2:Use \toprule, midrule, or \bottomrule from booktabs.
+  \hline  
+  ^^^^^^
+Message 22 in Test.tex: Comment displayed.
 % Verb check  
 ^
 Message 14 in Test.tex: Could not find argument for command.
diff --git a/Build/source/texk/chktex/chktex-1.6.6/Test.tex b/Build/source/texk/chktex/chktex-1.7.1/Test.tex
index c848fac7837..503e95ea6e4 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/Test.tex
+++ b/Build/source/texk/chktex/chktex-1.7.1/Test.tex
@@ -25,7 +25,7 @@ ${{[{(ab)}^{-1}]}}^{-2}$ is beautiful
 % Warning 4-6, 28
 
 Testing {\it italic} in \/ this {\em sentence\/}, as {\em you \/ see\/}.
-Testing {\it italic\/} in this {\em sentence}, as {\em you see}.
+Testing {\it italic\/} in this {\em sentence,} as {\em you see}.
 
 % LaTeX2e
 
@@ -67,8 +67,8 @@ Foo\dots bar. $1,\ldots,3$. $1+\cdots+3$. $1,\ldots,3$. $1\cdot\cdots\cdot3$.
 
 % Warning 12
 
-1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar
-1st.\ foo Inc.\ ab.cd.\ foo ab.cd.\ Foo.\ bar
+1st. Foo Inc. Ab.cd. foo ab.cd. Foo. bar baz., billy.; bob.: joe.! frank.? james.. george
+1st.\ foo Inc.\ ab.cd.\ foo ab.cd.\ Foo.\ bar baz., billy.; bob.:\ joe.!\ frank.?\ james..\ george
 
 % Warning 13
 
@@ -88,6 +88,7 @@ Is this an `example', or is it an `example'.
 % Warning 20
 
 That bug is \unknown\ to me.
+% That bug is \unknown\ to me.
 
 % Warning 21
 
@@ -119,7 +120,7 @@ Do you understand?
 \input input.tex
 \input input
 
-% Warning 29 
+% Warning 29
 The program opens a screen sized 640x200 pixels
 The program opens a screen sized $640\times200$ pixels
 
@@ -145,7 +146,7 @@ $\sin^2 + \cos^2 = 1$
 
 % Warning 36-37
 
-This( an example( Nuff said )), illustrates( ``my'' )point. 
+This( an example( Nuff said )), illustrates( ``my'' )point.
 This (an example (Nuff said)), illustrates (``my'') point.
 
 % Warning 38
@@ -169,6 +170,39 @@ foo \above qux
 This is a footnote \footnote{foo}.
 This is a footnote\footnote{foo}.
 
+% Warning 43
+Here is a mistake $\left{x\right}$.
+This one triggers warning 22 $\left\{x\right\}$.
+Here \chktex\ doesn't complain $\left\lbrace x\right\rbrace$.
+
+% Warning 44 -- user regex -- default message
+You should always write a good intro.
+You should always write a good introduction.
+
+% Warning 44 -- user regex -- user message
+For every $p\not|n$ you have an ugly prime which doesn't divide $n$.
+For every $p\nmid n$ you have a cute prime which doesn't divide $n$.
+
+% Math mode check
+\ensuremath{sin x\text{is not the same as sin x, but is the same as $sin x$}}
+Also, $x(3)\text{ is not x(3) but it is $x(3)$}$
+
+This is\\% a comment. Nothing here should be checked(right)?
+a broken line.
+But this is not a \% comment, so we should find this error(right)?
+
+Here(on this line only)is a warning $sin(x)$ suppressed. % chktex 36 chktex 35
+Here(on this line only)is a warning $sin(x)$ suppressed. % CHKTEX 35 36
+
+In section~\ref{sec:3} we have a warning.
+In section~\ref{sec:4} it is suppressed. % chktex -1
+% In section~\ref{sec:5} we don't have a warning.
+
+\begin{tabular*}{1.0\linewidth}[h]{|c|cc|}
+  a & b \\
+  \hline
+  c & d
+\end{tabular*}
 
 % Verb check
 
@@ -182,5 +216,3 @@ This is a footnote\footnote{foo}.
 % Warning 16,15
 
 $$(
-
-
diff --git a/Build/source/texk/chktex/chktex-1.6.6/Utility.c b/Build/source/texk/chktex/chktex-1.7.1/Utility.c
index 165c8d223c1..39beaa6cc83 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/Utility.c
+++ b/Build/source/texk/chktex/chktex-1.7.1/Utility.c
@@ -703,6 +703,7 @@ int PushFile(const char *Name, FILE * fh, struct Stack *stack)
 
 char *FGetsStk(char *Dest, unsigned long len, struct Stack *stack)
 {
+    static short HasSeenLong = 0;
     struct FileNode *fn;
     char *Retval = NULL;
 
@@ -714,13 +715,19 @@ char *FGetsStk(char *Dest, unsigned long len, struct Stack *stack)
             if (Retval) {
                 if (Retval[strlen(Retval)-1] == '\n')
                     fn->Line++;
+                /* We only want the long lines warning once per file */
+                else if (!HasSeenLong)
+                {
+                    PrintPrgErr(pmLongLines, BUFSIZ);
+                    HasSeenLong = 1;
+                }
                 break;
             }
 
             fn = StkPop(stack);
             fclose(fn->fh);
             free(fn);
-
+            HasSeenLong = 0;
         }
         while (!Retval && (fn = StkTop(stack)));
     }
diff --git a/Build/source/texk/chktex/chktex-1.6.6/Utility.h b/Build/source/texk/chktex/chktex-1.7.1/Utility.h
index 1293b8548f4..8afab6b67a0 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/Utility.h
+++ b/Build/source/texk/chktex/chktex-1.7.1/Utility.h
@@ -95,6 +95,12 @@ struct FileNode
 /* Rotates x n bits right (should be an int, long, etc.) */
 #define ROTATER(x,n) ((x>>n) | (x<<((CHAR_BIT*sizeof(x)) - n)))
 
+/* Subtract 1 because sizeof includes the null terminator.
+ * WARNING: To use this on a variable, the type should be char[]
+ * rather than char*, since for some versions of gcc these give
+ * different values. */
+#define STRLEN(x)  (sizeof(x)/sizeof(x[0]) - 1)
+
 int fexists(const char *Filename);
 
 void *sfmemset(void *to, int c, long n);
diff --git a/Build/source/texk/chktex/chktex-1.6.6/aclocal.m4 b/Build/source/texk/chktex/chktex-1.7.1/aclocal.m4
index 52c43e7af14..52c43e7af14 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/aclocal.m4
+++ b/Build/source/texk/chktex/chktex-1.7.1/aclocal.m4
diff --git a/Build/source/texk/chktex/chktex-1.6.6/autogen.sh b/Build/source/texk/chktex/chktex-1.7.1/autogen.sh
index 0982233b129..0982233b129 100755
--- a/Build/source/texk/chktex/chktex-1.6.6/autogen.sh
+++ b/Build/source/texk/chktex/chktex-1.7.1/autogen.sh
diff --git a/Build/source/texk/chktex/chktex-1.6.6/chktex.1 b/Build/source/texk/chktex/chktex-1.7.1/chktex.1
index 914076926a8..a3dcc13e3dc 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/chktex.1
+++ b/Build/source/texk/chktex/chktex-1.7.1/chktex.1
@@ -44,6 +44,10 @@ Makes msg # given a message and turns it on.
 .TP
 .B "-n --nowarn"
 Mutes msg # given.
+.TP
+.B "-L --nolinesupp"
+Do not allow per-line suppressions.  These are TeX comments of the form
+.I "% chktex ##".
 
 .PP
 Output control flags:
@@ -102,8 +106,8 @@ main document /usr/share/doc/chktex/ChkTeX.dvi.gz.
 Copyright (C) 1996 Jens T. Berger Thielemann
 .PP
 This program is free software; you can redistribute it and/or modify
-it under the terms of the 
-.I GNU General Public License 
+it under the terms of the
+.I GNU General Public License
 as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.
@@ -119,7 +123,7 @@ See the
 .I GNU General Public License
 for more details.
 .PP
-You should have received a copy of the 
+You should have received a copy of the
 .B GNU General Public License
 along with this program; if not, write to the
 .I Free Software Foundation, Inc.,
diff --git a/Build/source/texk/chktex/chktex-1.6.6/chktex.el b/Build/source/texk/chktex/chktex-1.7.1/chktex.el
index 8e02be26c9e..e61334796ca 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/chktex.el
+++ b/Build/source/texk/chktex/chktex-1.7.1/chktex.el
@@ -49,7 +49,7 @@
 (eval-after-load 'tex
   '(progn
      (add-to-list 'TeX-command-list
-                  '("ChkTeX" "chktex -v3 %s" TeX-run-compile nil t))))
+                  '("ChkTeX" "chktex -v6 %s" TeX-run-compile nil t))))
 
 (provide 'chktex)
 
diff --git a/Build/source/texk/chktex/chktex-1.6.6/chktexrc b/Build/source/texk/chktex/chktex-1.7.1/chktexrc
index 72889e2d707..f14c2522972 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/chktexrc
+++ b/Build/source/texk/chktex/chktex-1.7.1/chktexrc
@@ -56,8 +56,8 @@
 # look at the examples of their use.
 #
 # Please  also  note  that if you specify a list-keyword twice, we'll
-# concatenate  the  lists.   If you you specify a item-keyword twice,
-# we'll kill the previous value.
+# concatenate the lists.   If you specify a item-keyword twice, we'll
+# kill the previous value.
 #
 # We  are  slightly  context-sensitive when detecting tokens like "}"
 # and "]"; they have to be preceded by a space.  This generally makes
@@ -101,14 +101,14 @@
 # Quick summary of keywords follows.  Keywords marked with a * accept
 # keywords accepting case-insensitive lists.
 #
-#   Abbrev*     - A list of abbreviations not automatically catched.
+#   Abbrev*     - A list of abbreviations not automatically caught.
 #   CenterDots  - Commands/characters  which  should  have  \cdots in
 #                 between.
 #   CmdLine     - Default   commandline   options.    These  will  be
 #                 processed  before  the ones you give on the command
 #                 line.
 #   HyphDash   \
-#   NumDash     - No. of dashes allowed in different contexts.
+#   NumDash     - Number of dashes allowed in different contexts.
 #   WordDash   /
 #   IJAccent    - Commands   which   puts   an  accent  _over_  their
 #                 argument.
@@ -119,9 +119,11 @@
 #   LowDots     - Commands/characters  which  should  have  \ldots in
 #                 between.
 #   MathEnvir   - Environments which turn on math mode.
+#   MathCmd     - Commands which turn on math mode.
+#   TextCmd     - Commands which turn off math mode.
 #   MathRoman   - Mathematical   operators   with  LaTeX  replacement
 #                 defined.
-#   NoCharNext  - Insists on that certain commands aren't followed by 
+#   NoCharNext  - Insists on that certain commands aren't followed by
 #                 certain characters.
 #   NonItalic   - Commands immediately turning off italic mode.
 #   NotPreSpaced- Commands  which should not have a space in front of
@@ -180,7 +182,7 @@ CmdLine
 #
 # These  patterns  will  be  searched for through the text; no matter
 # whether   they   appear  as  normal  text,  commands  or  whatever.
-# Currently case-sensitive.
+# Currently case-sensitive.  They are not found in comments.
 #
 # I usually define a special command like this:
 #
@@ -214,6 +216,51 @@ UserWarn
 
 ]
 
+
+###
+#
+# These patterns will be searched for, no matter whether they appear
+# as normal text, commands or arguments.  However, they will _not_
+# match in verbatim environments.
+#
+# Remember that you have to escape (with a !) the following
+# characters: "#!= as well as spaces and {}[] if they are proceeded by
+# a space.
+#
+# Since these are PCRE regular expressions, you can use (?i) to make
+# the expression case insensitive.  See the man pages (man pcresyntax)
+# or the nicely formatted http://perldoc.perl.org/perlre.html for
+# documentation on the regular expression syntax.  Note however that
+# some the features of perl regular expression are not available such
+# as running code (callouts), and replacing.
+#
+# An initial PCRE comment (?# ... ) can be used change what is
+# displayed, thereby reminding yourself how to fix the problem.
+#
+###
+UserWarnRegex
+{
+
+  (?!#Always! use! \nmid)\\not! *(\||\\mid)
+
+  # capitalize section when saying Section 6.
+  (?!#-1:Capitalize! before! references)PCRE:\b(chapter|(sub)?section|theorem|lemma|proposition|corollary|appendix)~\\ref
+  (?!#1:Capitalize! before! references)POSIX:([^[:alnum:]]|^)(chapter|(sub)?section|theorem|lemma|proposition|corollary|appendix)~\\ref
+
+  # spell it out.
+  PCRE:(?i)\bintro\b(?!#Spell! it! out.! This! comment! is! not! used.)
+  POSIX:([^[:alnum:]]|^)intro([^[:alnum:]]|$)
+
+  # Pretty tables--see http://texdoc.net/texmf-dist/doc/latex/booktabs/booktabs.pdf
+  (?!#-2:Use! \toprule,! midrule,! or! \bottomrule! from! booktabs)\\hline
+  # This relies on it being on a single line, and not having anything
+  # else on that line.  With PCRE we could match balanced [] and {},
+  # but I wonder if it's worth the complexity...
+  (?!#-2:Vertical! rules! in! tables! are! ugly)\\begin\{(array|tabularx?\*?)\}(\[.*\])?\{.*\|.*\}
+
+}
+
+
 #####################################################################
 #
 # Here you can list the path of where ChkTeX should look for files it
@@ -237,11 +284,11 @@ TeXInputs
 
 #####################################################################
 #
-# Here you may specify more outputformats for use with the -v option,
+# Here you may specify more output formats for use with the -v option,
 # it simply indexes  into this list.  Remember to use ! instead of \,
 # though.
 #
-# For explanation of how % fields expand; look at ChkTeX.{dvi,ps}.
+# For explanation of how % fields expand; look at ChkTeX.{dvi,ps,pdf}.
 #
 # We will by default select entry number _two_ in this list (we count
 # from 0), and -v without any parameter selects entry number _three_.
@@ -268,14 +315,19 @@ OutFormat
 # -v5; no line number, ease auto-test
 "%k %n in %f: %m!n%r%s%t!n%u!n"
 
+# -v6; emacs compilation mode
+"!"%f!", line %l.%c:(#%n) %m!n"
+
 }
 
 
 
 #####################################################################
 #
-# These  commands  should be ignored when detecting whether a command
-# is ended by a space.
+# These commands should  be ignored when detecting  whether a command
+# is ended by a space.  You can specify regular expressions in the []
+# section in  case you  have many  custom macros  that can  be safely
+# terminated with a space.
 #
 
 Silent
@@ -312,28 +364,41 @@ Silent
 
     \textwidth \textheight \hsize \vsize
 
-    \if \fi
+    \if \fi \else
 
     \csname \endcsname
 
     \z@ \p@ \@warning \typeout
 
     \dots \ldots \input \endinput \nextline \leavevmode \cdots
--    \appendix \listfiles \and \quad
-    \vfill \vfil \hfill \hfil \topmargin \oddsidemargin
+    \appendix \listfiles \and \quad
+    \hskip \vfill \vfil \hfill \hfil \topmargin \oddsidemargin
     \frenchspacing \nonfrenchspacing
     \begingroup \endgroup \par
 
     \vrefwarning \upshape \headheight \headsep \hoffset \voffset
     \cdot \qquad
     \left \right
-}
+    \qedhere
+
+    \xspace
+
+    \addlinespace \cr \fill \frontmatter
+    \toprule \midrule \bottomrule
+
+}[
+# Here you can put regular expressions to match Silent macros.  It was
+# designed for  the case where you  have many custom macros  sharing a
+# common prefix, but can of course be used for other things.
+
+# \\my.*
+]
 
 #####################################################################
 #
 # Here,  you  can  specify the length of various dashes.  We sort the
 # dash according to which type of characters that are on the left and
-# right of of it.  We are only conclusive if they are the same.
+# right of it.  We are only conclusive if they are the same.
 #
 # We associate as follows:
 #
@@ -343,7 +408,7 @@ Silent
 #     WordDash    Space (like this --- see?)
 #
 # Below you specify how many dashes which are legal in each case.  We
-# define 0 as an magic constant which always generates an error.  You
+# define 0 as  a magic constant which always generates an error.  You
 # may specify more than one legal dash-length.
 #
 # Let's look at an example.  You use the following dash-syntax:
@@ -375,13 +440,15 @@ WordDash
 
 #####################################################################
 #
-# This  keyword  indicates commands  which argument isn't LaTeX code,
-# and which thus should be ignored.
+# This  keyword  indicates commands  whose argument isn't LaTeX code,
+# and thus should be ignored.
 #
-# After the  command,  you  may place arguments  that  you  wish that
-# should be  wiped in the process;  use [] for optional arguments, {}
-# for required  ones and *  if the  command  supports  an alternative
-# variant. These should be separated from the command with a colon.
+# After  the command,  you may  place  arguments that  you wish  that
+# should be wiped  in the process; use [] for  optional arguments, {}
+# for  required ones  and *  if the  command supports  an alternative
+# variant.  These should be separated  from the command with a colon.
+# Some  commands (e.g.  \cmidrule)  use ()  to  delimit and  optional
+# argument and so this syntax is supported as well.
 #
 # For  instance,  if  you would like to wipe the \newcommand command,
 # you would declare it as \newcommand:*[][]{}
@@ -392,15 +459,25 @@ WordDash
 
 WipeArg
 {
-    \label:{} \ref:{} \vref:{} \pageref:{} \index:{} \cite:[]{}
+    \label:{} \ref:{} \eqref:{} \vref:{} \pageref:{} \index:[]{}
+    \cite:[]{} \nocite:{}
     \input:{} \verbatiminput:[]{} \listinginput:[]{}{}
-    \verbatimtabinput:[]{} \include:{} \includeonly:{} 
+    \verbatimtabinput:[]{} \include:{} \includeonly:{}
     \bibitem:[]{}
+    \cline:{} \cmidrule:[](){}
+    \href:{}{}
+    # Cleveref -- there are many others that could be here as well...
+    \cref:*{} \cpageref:*{} \crefrange:*{}{} \cpagerefrange:*{}{}
+    \Cref:*{} \Cpageref:*{} \Crefrange:*{}{} \Cpagerefrange:*{}{}
+    # natbib
+    \citet:*[][]{} \citep:*[][]{} \citealt:*{} \citealp:*[]{} \citeauthor:*{}
+    \Citet:*[][]{} \Citep:*[][]{} \Citealt:*{} \Citealp:*[]{} \Citeauthor:{}
+    \citetext:{} \citeyear:*{} \citeyearpar:{}
 }
 
 #####################################################################
 #
-# These  environments  contains  material  which  will  be typeset as
+# These environments contain material which will be typeset as
 # mathematics by LaTeX.  This turns on/off some warnings.
 #
 # We will automagically append a * to each keyword.
@@ -414,6 +491,31 @@ MathEnvir
 
 #####################################################################
 #
+# These commands contain material which will be typeset as mathematics
+# by LaTeX.  The commands are assumed to have one mandatory argument
+# which is in math mode.  This turns on/off some warnings.
+#
+
+MathCmd
+{
+    \ensuremath
+}
+
+#####################################################################
+#
+# These commands contain material which will _not_ be typeset as
+# mathematics by LaTeX even if it would otherwise be in mathmode.  The
+# commands are assumed to have one mandatory argument which is in text
+# mode.  This turns on/off some warnings.
+#
+
+TextCmd
+{
+    \text \intertext \shortintertext \mbox
+}
+
+#####################################################################
+#
 # These  environments  contains  material  which  contents  should be
 # ignored.
 #
@@ -423,6 +525,7 @@ MathEnvir
 VerbEnvir
 {
     verbatim comment listing verbatimtab rawhtml errexam picture texdraw
+    filecontents pgfpicture tikzpicture
 }
 
 #####################################################################
@@ -444,7 +547,6 @@ VerbEnvir
 # by Russ Bubley, <russ@scs.leeds.ac.uk>.
 #
 
-
 Abbrev
 {
 # Ordinals
@@ -538,10 +640,10 @@ NonItalic
 
 #####################################################################
 #
-# Commands   which puts their argument into italic (and thus possibly
+# Commands which  put their argument  into italic (and  thus possibly
 # needs italic correction in the end).
 #
-# This is currently empty, since \textit, \textsl and \emph do that
+# This is currently  empty, since \textit, \textsl and  \emph do that
 # automatically.
 #
 
@@ -582,7 +684,7 @@ NotPreSpaced
 
 Linker
 {
-    \ref \vref \pageref \cite
+    \ref \vref \pageref \eqref \cite
 }
 
 #####################################################################
@@ -623,8 +725,9 @@ MathRoman
 
 #####################################################################
 #
-# These TeX commands have become unnecessary, as there are LaTeX cmds
-# that does the same. Purists should thus avoid these in their code.
+# These  TeX commands  have become  unnecessary, as  there are  LaTeX
+# commands that  does the same.   Purists should thus avoid  these in
+# their code.
 #
 # (These are a spell-corrected version of those lacheck uses).
 #
@@ -640,11 +743,11 @@ Primitives
 #
 # Format: \command:characters
 #
-# We'll emit a warning if any of characters are found after the 
+# We'll emit a warning if any of characters are found after the
 # command.
 #
 
-NoCharNext 
+NoCharNext
 {
    \left:{}$ \right:{}$
 }
@@ -652,18 +755,18 @@ NoCharNext
 #####################################################################
 #
 # We're killing \verb@...@ commands and the arguments of the commands
-# listed above in WIPEARG by overwriting them with a string or a
+# listed above in WipeArg by overwriting them with a string or a
 # single character.
 #
-# This  should  not contain an alphabetic character (in case the user
-# writes (\foo\verb@bar@), neither should it contain be one of LaTeX'
-# reserved  characters  (`#$%&~_^\{}'),  or any parenthesis character
-# ('()[]{}').   If  possible,  don't  use  a  punctuation  character,
-# either, or any spacing character.
+# This should not  contain an alphabetic character (in  case the user
+# writes  (\foo\verb@bar@),  neither  should  it contain  be  one  of
+# LaTeX's  reserved  characters  (`#$%&~_^\{}'), or  any  parenthesis
+# character  ('()[]{}').   If  possible,   don't  use  a  punctuation
+# character, either, or any spacing character.
 #
-# The  asterix is also unsuitable, as some commands behave in another
-# way  if  they  are  postpended with an asterix.  Which more or less
-# leaves  us  with  the  pipe.
+# The asterisk is also unsuitable, as some commands behave in another
+# way if  they are  appended with  an asterisk.   Which more  or less
+# leaves us with the pipe.
 #
 # Please  note  that  this  may  also  be  a  _string_, which will be
 # repeated until the proper length is reached.
@@ -675,4 +778,3 @@ VerbClear = "|"
 # All for now - have fun.
 #
 #####################################################################
-
diff --git a/Build/source/texk/chktex/chktex-1.6.6/chkweb.1 b/Build/source/texk/chktex/chktex-1.7.1/chkweb.1
index 5cb7063f786..5cb7063f786 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/chkweb.1
+++ b/Build/source/texk/chktex/chktex-1.7.1/chkweb.1
diff --git a/Build/source/texk/chktex/chktex-1.6.6/chkweb.sh b/Build/source/texk/chktex/chktex-1.7.1/chkweb.sh
index 8d6361d1097..8d6361d1097 100755
--- a/Build/source/texk/chktex/chktex-1.6.6/chkweb.sh
+++ b/Build/source/texk/chktex/chktex-1.7.1/chkweb.sh
diff --git a/Build/source/texk/chktex/chktex-1.6.6/config.h.in b/Build/source/texk/chktex/chktex-1.7.1/config.h.in
index 273502cac45..4c5c597974d 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/config.h.in
+++ b/Build/source/texk/chktex/chktex-1.7.1/config.h.in
@@ -40,6 +40,12 @@
 /* Define to 1 if you have the `opendir' function. */
 #undef HAVE_OPENDIR
 
+/* "Whether PCRE can be used for user warnings." */
+#undef HAVE_PCRE
+
+/* "Whether PCRE can be used for user warnings." */
+#undef HAVE_POSIX_ERE
+
 /* Define to 1 if you have the `readdir' function. */
 #undef HAVE_READDIR
 
diff --git a/Build/source/texk/chktex/chktex-1.6.6/configure.in b/Build/source/texk/chktex/chktex-1.7.1/configure.in
index 5637cb68662..cebe7921f6b 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/configure.in
+++ b/Build/source/texk/chktex/chktex-1.7.1/configure.in
@@ -27,7 +27,7 @@ dnl
 
 
 dnl Process this file with autoconf to produce a configure script.
-AC_INIT(ChkTeX, 1.6.6)
+AC_INIT(ChkTeX, 1.7.1)
 AC_SUBST(SCRIPTS)
 AC_SUBST(BUILT_SCRIPTS)
 AC_SUBST(ELISPDIR)
@@ -35,6 +35,16 @@ ELISPDIR=
 AC_SUBST(CLEAN)
 CLEAN=
 
+AC_ARG_ENABLE(pcre,[
+    --enable-pcre:             Use PCRE to allow regular expressions in
+                               user warnings.  (Default:  yes, if available).],,
+enable_pcre=yes)
+
+AC_ARG_ENABLE(posixre,[
+    --enable-posixre:          Use POSIX extended regular expressions in
+                               user warnings.  (Default:  yes, unless using PCRE).],,
+enable_posixre=yes)
+
 AC_ARG_ENABLE(lacheck-replace,[
     --enable-lacheck-replace:  Installs  a lacheck replacement for the
                                AUC-TeX interface.  (Default:  no).],,
@@ -94,6 +104,7 @@ else
   AC_MSG_RESULT(no)
 fi
 
+
 dnl Check compiler and flags
 AC_PROG_CC
 AX_CFLAGS_STRICT_PROTOTYPES
@@ -153,6 +164,50 @@ AC_FUNC_VPRINTF
 AC_CHECK_FUNCS(access closedir fileno isatty opendir readdir stat dnl
 strcasecmp strdup strlwr strtol)
 
+
+dnl Check for PCRE regular expression support
+AC_MSG_CHECKING(whether PCRE regular expressions are enabled)
+AC_MSG_RESULT($enable_pcre)
+if test "$enable_pcre" = "yes"; then
+  AC_CHECK_PROG(WITH_PCRE, pcre-config, yes, no)
+  if test "$WITH_PCRE" = "yes"; then
+    AC_DEFINE(HAVE_PCRE, 1, "Whether PCRE can be used for user warnings.")
+    CFLAGS="${CFLAGS} $(pcre-config --cflags-posix)"
+    LDFLAGS="${LDFLAGS} $(pcre-config --libs-posix)"
+  else
+    AC_DEFINE(HAVE_PCRE, 0, "Whether PCRE can be used for user warnings.")
+    AC_MSG_WARN(PCRE library not found.)
+  fi
+else
+    AC_DEFINE(HAVE_PCRE, 0, "Whether PCRE can be used for user warnings.")
+    AC_MSG_WARN(PCRE regular expressions not enabled.)
+fi
+
+dnl Check for POSIX extended regular expression support
+AC_MSG_CHECKING(for POSIX extended regular expressions)
+AC_EGREP_CPP([yes],
+  [#include <regex.h>
+  #ifdef REG_EXTENDED
+  yes
+  # endif
+  ], posix_ere=yes, posix_ere=no)
+AC_MSG_RESULT($posix_ere)
+if test "$WITH_PCRE" = "yes"; then
+    AC_DEFINE(HAVE_POSIX_ERE, 0, "Whether POSIX ERE can be used for user warnings.")
+else
+  if test "$enable_posixre" = "yes"; then
+    if test "$posix_ere" = "yes"; then
+      AC_DEFINE(HAVE_POSIX_ERE, 1, "Whether PCRE can be used for user warnings.")
+    else
+      AC_DEFINE(HAVE_POSIX_ERE, 0, "Whether PCRE can be used for user warnings.")
+    fi
+  else
+    AC_DEFINE(HAVE_POSIX_ERE, 0, "Whether PCRE can be used for user warnings.")
+    AC_MSG_WARN(Regular expressions not enabled.)
+  fi
+fi
+
+
 AC_CONFIG_HEADER(config.h)
 AC_CONFIG_FILES([stamp-h], [echo timestamp > stamp-h])
 AC_OUTPUT(Makefile deweb rmeheader ChkTeX.tex)
diff --git a/Build/source/texk/chktex/chktex-1.6.6/deweb.1 b/Build/source/texk/chktex/chktex-1.7.1/deweb.1
index 43770aa1fd3..43770aa1fd3 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/deweb.1
+++ b/Build/source/texk/chktex/chktex-1.7.1/deweb.1
diff --git a/Build/source/texk/chktex/chktex-1.6.6/deweb.in b/Build/source/texk/chktex/chktex-1.7.1/deweb.in
index 91750e636a2..91750e636a2 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/deweb.in
+++ b/Build/source/texk/chktex/chktex-1.7.1/deweb.in
diff --git a/Build/source/texk/chktex/chktex-1.6.6/input.tex b/Build/source/texk/chktex/chktex-1.7.1/input.tex
index 76bc301ff25..76bc301ff25 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/input.tex
+++ b/Build/source/texk/chktex/chktex-1.7.1/input.tex
diff --git a/Build/source/texk/chktex/chktex-1.6.6/lacheck b/Build/source/texk/chktex/chktex-1.7.1/lacheck
index da75d360dee..da75d360dee 100755
--- a/Build/source/texk/chktex/chktex-1.6.6/lacheck
+++ b/Build/source/texk/chktex/chktex-1.7.1/lacheck
diff --git a/Build/source/texk/chktex/chktex-1.6.6/m4/ax_cflags_strict_prototypes.m4 b/Build/source/texk/chktex/chktex-1.7.1/m4/ax_cflags_strict_prototypes.m4
index 06ec9e2f27b..06ec9e2f27b 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/m4/ax_cflags_strict_prototypes.m4
+++ b/Build/source/texk/chktex/chktex-1.7.1/m4/ax_cflags_strict_prototypes.m4
diff --git a/Build/source/texk/chktex/chktex-1.6.6/m4/vl_prog_cc_warnings.m4 b/Build/source/texk/chktex/chktex-1.7.1/m4/vl_prog_cc_warnings.m4
index fe2f6145450..fe2f6145450 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/m4/vl_prog_cc_warnings.m4
+++ b/Build/source/texk/chktex/chktex-1.7.1/m4/vl_prog_cc_warnings.m4
diff --git a/Build/source/texk/chktex/chktex-1.6.6/rmeheader.in b/Build/source/texk/chktex/chktex-1.7.1/rmeheader.in
index 56ca58ae76e..56ca58ae76e 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/rmeheader.in
+++ b/Build/source/texk/chktex/chktex-1.7.1/rmeheader.in
diff --git a/Build/source/texk/chktex/chktex-1.6.6/types.h b/Build/source/texk/chktex/chktex-1.7.1/types.h
index a26b95295e4..a26b95295e4 100644
--- a/Build/source/texk/chktex/chktex-1.6.6/types.h
+++ b/Build/source/texk/chktex/chktex-1.7.1/types.h
diff --git a/Build/source/texk/chktex/config.h.in b/Build/source/texk/chktex/config.h.in
index a4eb6d62a07..aa228abcdee 100644
--- a/Build/source/texk/chktex/config.h.in
+++ b/Build/source/texk/chktex/config.h.in
@@ -79,6 +79,12 @@
 /* Define to 1 if you have the `opendir' function. */
 #undef HAVE_OPENDIR
 
+/* Whether PCRE can be used for user warnings. */
+#undef HAVE_PCRE
+
+/* Whether POSIX ERE can be used for user warnings. */
+#undef HAVE_POSIX_ERE
+
 /* Define to 1 if you have the `putenv' function. */
 #undef HAVE_PUTENV
 
diff --git a/Build/source/texk/chktex/configure b/Build/source/texk/chktex/configure
index 21807be0fb4..80954515836 100755
--- a/Build/source/texk/chktex/configure
+++ b/Build/source/texk/chktex/configure
@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.69 for ChkTeX for TeX Live 1.6.6.
+# Generated by GNU Autoconf 2.69 for ChkTeX for TeX Live 1.7.1.
 #
 # Report bugs to <tex-k@tug.org>.
 #
@@ -590,12 +590,12 @@ MAKEFLAGS=
 # Identity of this package.
 PACKAGE_NAME='ChkTeX for TeX Live'
 PACKAGE_TARNAME='chktex-for-tex-live'
-PACKAGE_VERSION='1.6.6'
-PACKAGE_STRING='ChkTeX for TeX Live 1.6.6'
+PACKAGE_VERSION='1.7.1'
+PACKAGE_STRING='ChkTeX for TeX Live 1.7.1'
 PACKAGE_BUGREPORT='tex-k@tug.org'
 PACKAGE_URL=''
 
-ac_unique_file="chktex-1.6.6/ChkTeX.c"
+ac_unique_file="chktex-1.7.1/ChkTeX.c"
 # Factoring default headers for most tests.
 ac_includes_default="\
 #include <stdio.h>
@@ -646,8 +646,8 @@ WIN32_WRAP_FALSE
 WIN32_WRAP_TRUE
 WIN32_FALSE
 WIN32_TRUE
-PDF_DEPEND
-PDFLATEX
+MINGW32_FALSE
+MINGW32_TRUE
 WARNING_CFLAGS
 CPP
 OTOOL64
@@ -787,8 +787,7 @@ CFLAGS
 LDFLAGS
 LIBS
 CPPFLAGS
-CPP
-PDFLATEX'
+CPP'
 
 
 # Initialize some variables set by options.
@@ -1329,7 +1328,7 @@ if test "$ac_init_help" = "long"; then
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures ChkTeX for TeX Live 1.6.6 to adapt to many kinds of systems.
+\`configure' configures ChkTeX for TeX Live 1.7.1 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1400,7 +1399,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of ChkTeX for TeX Live 1.6.6:";;
+     short | recursive ) echo "Configuration of ChkTeX for TeX Live 1.7.1:";;
    esac
   cat <<\_ACEOF
 
@@ -1448,7 +1447,6 @@ Some influential environment variables:
   CPPFLAGS    (Objective) C/C++ preprocessor flags, e.g. -I<include dir> if
               you have headers in a nonstandard directory <include dir>
   CPP         C preprocessor
-  PDFLATEX    pdfLaTeX command
 
 Use these variables to override the choices made by `configure' or to help
 it to find libraries and programs with nonstandard names/locations.
@@ -1516,7 +1514,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-ChkTeX for TeX Live configure 1.6.6
+ChkTeX for TeX Live configure 1.7.1
 generated by GNU Autoconf 2.69
 
 Copyright (C) 2012 Free Software Foundation, Inc.
@@ -2126,7 +2124,7 @@ cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by ChkTeX for TeX Live $as_me 1.6.6, which was
+It was created by ChkTeX for TeX Live $as_me 1.7.1, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   $ $0 $@
@@ -7518,7 +7516,7 @@ fi
 
 # Define the identity of the package.
  PACKAGE='chktex-for-tex-live'
- VERSION='1.6.6'
+ VERSION='1.7.1'
 
 
 cat >>confdefs.h <<_ACEOF
@@ -12772,51 +12770,6 @@ WARNING_CFLAGS=$kpse_cv_warning_cflags
 
 
 
-for ac_prog in pdflatex
-do
-  # Extract the first word of "$ac_prog", so it can be a program name with args.
-set dummy $ac_prog; ac_word=$2
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
-$as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_prog_PDFLATEX+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  if test -n "$PDFLATEX"; then
-  ac_cv_prog_PDFLATEX="$PDFLATEX" # Let the user override the test.
-else
-as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
-for as_dir in $PATH
-do
-  IFS=$as_save_IFS
-  test -z "$as_dir" && as_dir=.
-    for ac_exec_ext in '' $ac_executable_extensions; do
-  if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
-    ac_cv_prog_PDFLATEX="$ac_prog"
-    $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
-    break 2
-  fi
-done
-  done
-IFS=$as_save_IFS
-
-fi
-fi
-PDFLATEX=$ac_cv_prog_PDFLATEX
-if test -n "$PDFLATEX"; then
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: $PDFLATEX" >&5
-$as_echo "$PDFLATEX" >&6; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }
-fi
-
-
-  test -n "$PDFLATEX" && break
-done
-test -n "$PDFLATEX" || PDFLATEX="no"
-
-
-
 for ac_header in stat.h stdarg.h sys/stat.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
@@ -12863,15 +12816,19 @@ fi
 done
 
 
-test "x$enable_maintainer_mode" = xyes && PDF_DEPEND=ChkTeX.tex
-
-
 ac_config_headers="$ac_config_headers config.h"
 
 
+
 $as_echo "#define TEX_LIVE 1" >>confdefs.h
 
 
+$as_echo "#define HAVE_PCRE 0" >>confdefs.h
+
+
+$as_echo "#define HAVE_POSIX_ERE 1" >>confdefs.h
+
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for native WIN32 or MINGW32" >&5
 $as_echo_n "checking for native WIN32 or MINGW32... " >&6; }
 if ${kpse_cv_have_win32+:} false; then :
@@ -12918,6 +12875,14 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $kpse_cv_have_win32" >&5
 $as_echo "$kpse_cv_have_win32" >&6; }
 
+ if test "x$kpse_cv_have_win32" = xmingw32; then
+  MINGW32_TRUE=
+  MINGW32_FALSE='#'
+else
+  MINGW32_TRUE='#'
+  MINGW32_FALSE=
+fi
+
  if test "x$kpse_cv_have_win32" != xno; then
   WIN32_TRUE=
   WIN32_FALSE='#'
@@ -12935,7 +12900,7 @@ else
 fi
 
 
-CHKTEX_TREE=chktex-1.6.6
+CHKTEX_TREE=chktex-1.7.1
 
 PERL5='/usr/bin/env perl'
 
@@ -13354,7 +13319,7 @@ Usage: $0 [OPTIONS]
 Report bugs to <bug-libtool@gnu.org>."
 
 lt_cl_version="\
-ChkTeX for TeX Live config.lt 1.6.6
+ChkTeX for TeX Live config.lt 1.7.1
 configured by $0, generated by GNU Autoconf 2.69.
 
 Copyright (C) 2011 Free Software Foundation, Inc.
@@ -14402,9 +14367,7 @@ fi
 
 ac_config_files="$ac_config_files Makefile"
 
-ac_config_files="$ac_config_files ChkTeX.tmp:chktex-1.6.6/ChkTeX.tex.in"
-
-ac_config_files="$ac_config_files deweb.pl:chktex-1.6.6/deweb.in"
+ac_config_files="$ac_config_files deweb.pl:chktex-1.7.1/deweb.in"
 
 
 cat >confcache <<\_ACEOF
@@ -14544,6 +14507,10 @@ if test -z "${am__fastdepCC_TRUE}" && test -z "${am__fastdepCC_FALSE}"; then
   as_fn_error $? "conditional \"am__fastdepCC\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${MINGW32_TRUE}" && test -z "${MINGW32_FALSE}"; then
+  as_fn_error $? "conditional \"MINGW32\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 if test -z "${WIN32_TRUE}" && test -z "${WIN32_FALSE}"; then
   as_fn_error $? "conditional \"WIN32\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
@@ -14949,7 +14916,7 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by ChkTeX for TeX Live $as_me 1.6.6, which was
+This file was extended by ChkTeX for TeX Live $as_me 1.7.1, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -15015,7 +14982,7 @@ _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
 ac_cs_version="\\
-ChkTeX for TeX Live config.status 1.6.6
+ChkTeX for TeX Live config.status 1.7.1
 configured by $0, generated by GNU Autoconf 2.69,
   with options \\"\$ac_cs_config\\"
 
@@ -15428,8 +15395,7 @@ do
     "libtool") CONFIG_COMMANDS="$CONFIG_COMMANDS libtool" ;;
     "config.h") CONFIG_HEADERS="$CONFIG_HEADERS config.h" ;;
     "Makefile") CONFIG_FILES="$CONFIG_FILES Makefile" ;;
-    "ChkTeX.tmp") CONFIG_FILES="$CONFIG_FILES ChkTeX.tmp:chktex-1.6.6/ChkTeX.tex.in" ;;
-    "deweb.pl") CONFIG_FILES="$CONFIG_FILES deweb.pl:chktex-1.6.6/deweb.in" ;;
+    "deweb.pl") CONFIG_FILES="$CONFIG_FILES deweb.pl:chktex-1.7.1/deweb.in" ;;
 
   *) as_fn_error $? "invalid argument: \`$ac_config_target'" "$LINENO" 5;;
   esac
diff --git a/Build/source/texk/chktex/configure.ac b/Build/source/texk/chktex/configure.ac
index 9be21f06670..a0063c59f64 100644
--- a/Build/source/texk/chktex/configure.ac
+++ b/Build/source/texk/chktex/configure.ac
@@ -22,9 +22,6 @@ AC_CONFIG_MACRO_DIR([../../m4])
 dnl Common code for all programs using libkpathsea.
 KPSE_COMMON([chktex])
 
-dnl Checks for programs.
-KPSE_CHECK_PDFLATEX
-
 dnl No termlib/termcap/ncurses library for TeX Live
 
 dnl Checks for header files.
@@ -34,14 +31,15 @@ dnl Checks for library functions.
 AC_FUNC_VPRINTF
 AC_CHECK_FUNCS([access closedir fileno isatty opendir readdir stat strcasecmp strdup strlwr strtol])
 
-dnl Rebuild ChkTeX.pdf if required and maintainer-mode is enabled.
-test "x$enable_maintainer_mode" = xyes && PDF_DEPEND=ChkTeX.tex
-AC_SUBST([PDF_DEPEND])
-
 AC_CONFIG_HEADERS([config.h])
+
+dnl For TeX Live we always use Posix extended regular expressions
 AC_DEFINE([TEX_LIVE], 1, [Define to 1 for a TeX Live build.])
+AC_DEFINE([HAVE_PCRE], 0, [Whether PCRE can be used for user warnings.])
+AC_DEFINE([HAVE_POSIX_ERE], 1, [Whether POSIX ERE can be used for user warnings.])
 
 KPSE_CHECK_WIN32
+AM_CONDITIONAL([MINGW32], [test "x$kpse_cv_have_win32" = xmingw32])
 AM_CONDITIONAL([WIN32], [test "x$kpse_cv_have_win32" != xno])
 AM_CONDITIONAL([WIN32_WRAP],
                [test -r $srcdir/../../texk/texlive/w32_wrapper/runscript.exe])
@@ -52,7 +50,6 @@ AC_SUBST([PERL5], ['/usr/bin/env perl'])
 KPSE_KPATHSEA_FLAGS
 
 AC_CONFIG_FILES([Makefile])
-AC_CONFIG_FILES([ChkTeX.tmp:chktex-]chktex_version[/ChkTeX.tex.in])
 AC_CONFIG_FILES([deweb.pl:chktex-]chktex_version[/deweb.in], [chmod +x deweb.pl])
 
 AC_OUTPUT
diff --git a/Build/source/texk/chktex/regex/COPYING.LIB b/Build/source/texk/chktex/regex/COPYING.LIB
new file mode 100644
index 00000000000..cf9b6b99726
--- /dev/null
+++ b/Build/source/texk/chktex/regex/COPYING.LIB
@@ -0,0 +1,510 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+Licenses are intended to guarantee your freedom to share and change
+free software--to make sure the software is free for all its users.
+
+  This license, the Lesser General Public License, applies to some
+specially designated software packages--typically libraries--of the
+Free Software Foundation and other authors who decide to use it.  You
+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
+strategy to use in any particular case, based on the explanations
+below.
+
+  When we speak of free software, we are referring to freedom of use,
+not price.  Our General Public Licenses are designed to make sure that
+you have the freedom to distribute copies of free software (and charge
+for this service if you wish); that you receive source code or can get
+it if you want it; that you can change the software and use pieces of
+it in new free programs; and that you are informed that you can do
+these things.
+
+  To protect your rights, we need to make restrictions that forbid
+distributors to deny you these rights or to ask you to surrender these
+rights.  These restrictions translate to certain responsibilities for
+you if you distribute copies of the library or if you modify it.
+
+  For example, if you distribute copies of the library, whether gratis
+or for a fee, you must give the recipients all the rights that we gave
+you.  You must make sure that they, too, receive or can get the source
+code.  If you link other code with the library, you must provide
+complete object files to the recipients, so that they can relink them
+with the library after making changes to the library and recompiling
+it.  And you must show them these terms so they know their rights.
+
+  We protect your rights with a two-step method: (1) we copyright the
+library, and (2) we offer you this license, which gives you legal
+permission to copy, distribute and/or modify the library.
+
+  To protect each distributor, we want to make it very clear that
+there is no warranty for the free library.  Also, if the library is
+modified by someone else and passed on, the recipients should know
+that what they have is not the original version, so that the original
+author's reputation will not be affected by problems that might be
+introduced by others.
+^L
+  Finally, software patents pose a constant threat to the existence of
+any free program.  We wish to make sure that a company cannot
+effectively restrict the users of a free program by obtaining a
+restrictive license from a patent holder.  Therefore, we insist that
+any patent license obtained for a version of the library must be
+consistent with the full freedom of use specified in this license.
+
+  Most GNU software, including some libraries, is covered by the
+ordinary GNU General Public License.  This license, the GNU Lesser
+General Public License, applies to certain designated libraries, and
+is quite different from the ordinary General Public License.  We use
+this license for certain libraries in order to permit linking those
+libraries into non-free programs.
+
+  When a program is linked with a library, whether statically or using
+a shared library, the combination of the two is legally speaking a
+combined work, a derivative of the original library.  The ordinary
+General Public License therefore permits such linking only if the
+entire combination fits its criteria of freedom.  The Lesser General
+Public License permits more lax criteria for linking other code with
+the library.
+
+  We call this license the "Lesser" General Public License because it
+does Less to protect the user's freedom than the ordinary General
+Public License.  It also provides other free software developers Less
+of an advantage over competing non-free programs.  These disadvantages
+are the reason we use the ordinary General Public License for many
+libraries.  However, the Lesser license provides advantages in certain
+special circumstances.
+
+  For example, on rare occasions, there may be a special need to
+encourage the widest possible use of a certain library, so that it
+becomes a de-facto standard.  To achieve this, non-free programs must
+be allowed to use the library.  A more frequent case is that a free
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diff --git a/Build/source/texk/chktex/regex/README b/Build/source/texk/chktex/regex/README
new file mode 100644
index 00000000000..9b3e8979205
--- /dev/null
+++ b/Build/source/texk/chktex/regex/README
@@ -0,0 +1,122 @@
+This is the regex functionality from glibc 2.5 extracted into a
+separate library, for Win32.  It may be built, from the sources
+provided, using the command sequence:--
+
+  ./configure [--options...] && make
+
+For a list of available configuration options, run:--
+
+  ./configure --help
+
+After building, as above, the resultant DLL, and optionally the
+associated development kit, may be installed by:--
+
+  make install
+
+while redistributable binary DLL and development library kits may
+be created by:--
+
+  make dist
+
+
+The original sources, on which this port is based, remain
+copyright of their respective authors, or of the Free Software
+Foundation Inc., as indicated in individual file headers; all are
+redistributed with permission, as granted by the GNU Lesser
+General Public License.
+
+This is free software.  It is provided AS IS, in the hope that
+it may be useful, but WITHOUT WARRANTY OF ANY KIND, not even an
+IMPLIED WARRANTY of MERCHANTABILITY, nor of FITNESS FOR ANY
+PARTICULAR PURPOSE.
+
+Permission is granted to redistribute this software, either
+"as is" or in modified form, under the terms of the GNU Lesser
+General Public License, as published by the Free Software
+Foundation; either version 2.1, or (at your option) any later
+version.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this software; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, 51 Franklin St -
+Fifth Floor, Boston, MA 02110-1301, USA.
+
+The original port of this functionality was implemented by Tor
+Lillqvist; I've adapted his work, to make it somewhat more MinGW
+friendly.  I have *not* modified any of the `C' sources provided
+by Tor; nor have I changed the naming conventions he adopted for
+generated distributables.  I *have*:--
+
+1) Replaced Tor's original `Makefile' with an autoconf generated
+   configure script, and a backwardly compatible `Makefile.in';
+   this provides a more flexible build procedure, which I find
+   more convenient, when cross-compiling on a GNU/Linux host.
+
+2) Added VPATH support, for `out of tree' builds.
+
+3) Adapted the build procedure, to avoid a dependency on the `lib'
+   program from Microsoft's MSVC tool chain.  This is achieved by
+   providing an option to configure, which is disabled by default;
+   it may by activated by specifying `--enable-msvc-implib' on the
+   configure command line.  If this option is not activated, or if
+   the MSVC `lib' tool is not present, the Makefile is configured
+   without binding the rule for building an MSVC compatible import
+   library, to the default target, (although the rule is left in
+   place for explicit use).
+
+   If the `--enable-msvc-implib' option is specified, but `lib' is
+   not present, then configure will issue a warning message, and
+   will again configure the Makefile without binding this rule to
+   the default target.
+
+   Only if the `--enable-msvc-implib' option is specified, *and*
+   the `lib' tool is present, will building of an MSVC compatible
+   import library be configured as a default deliverable.
+
+4) Added `install', `install-dll' and `install-dev' targets, to
+   support direct installation of the DLL, and its associated
+   development kit.
+
+5) Changed the default packaging format for distributables, from
+   Tor's exclusive choice of `zip', to my own preferred `tar.gz';
+   `zip' format remains available, as an option, by configuring
+   with `--enable-dist=zip'.
+
+6) Added `bindist', `devdist' and `srcdist' targets, for greater
+   flexibility in building distribution kits.
+
+The original text of Tor's README file will be found below.
+
+--Keith Marshall  <keithmarshall@users.sourceforge.net>
+
+I call the DLL libgnurx-0.dll which hopefully should be unique. At
+least it isn't "regex.dll" which has been used by the
+gnuwin32.sourceforge.net site for *two* incompatible DLLs. (That mess,
+and the mess with their build of Henry Spencer's regex library, was
+what lead me to build my own GNU regex library. See the
+gnuwin32-users mailing list archives from December 2006.)
+
+The "-0" is so that if at some point I build a release that isn't
+binary compatible, I can then increment that and use a different name.
+
+The import library for gcc is called libgnurx.dll.a, but I also
+distribute a copy of it called libregex.a so that configure scripts
+that look for -lregex will work.
+
+Note that none of the wide-character and i18n functionality which is
+built when this is part of glibc gets compiled. Thus things like
+character classes most probably work only for single-byte codepages.
+
+Compiling that stuff would drag in lots of glibc's locale handling
+stuff which is completely incompatible with Microsoft's C library's
+locale handling anyway. Also, I am not sure whether the GNU regex code
+is prepared to handle a two-byte wchar_t, or does it assume that
+wchar_t is int as it is on Linux? Hmm, actually there is lots of
+sizeof(wchar_t) in glibc, so maybe it *is* prepared? Maybe
+later... But anyway, it would presumably mean we should have not just
+the regex functionality but a larger subset of glibc that would
+include all locale, ctype, wchar, mbs, etc stuff, presumably ending up
+with a very large part of glibc (not the system calls,
+obviously). Indeed, something to save for later, or never...
+
+--Tor Lillqvist <tml@iki.fi>, <tml@novell.com>
diff --git a/Build/source/texk/chktex/regex/regcomp.c b/Build/source/texk/chktex/regex/regcomp.c
new file mode 100644
index 00000000000..78a1218cf86
--- /dev/null
+++ b/Build/source/texk/chktex/regex/regcomp.c
@@ -0,0 +1,3800 @@
+/* Extended regular expression matching and search library.
+   Copyright (C) 2002,2003,2004,2005,2006 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+static reg_errcode_t re_compile_internal (regex_t *preg, const char * pattern,
+					  size_t length, reg_syntax_t syntax);
+static void re_compile_fastmap_iter (regex_t *bufp,
+				     const re_dfastate_t *init_state,
+				     char *fastmap);
+static reg_errcode_t init_dfa (re_dfa_t *dfa, size_t pat_len);
+#ifdef RE_ENABLE_I18N
+static void free_charset (re_charset_t *cset);
+#endif /* RE_ENABLE_I18N */
+static void free_workarea_compile (regex_t *preg);
+static reg_errcode_t create_initial_state (re_dfa_t *dfa);
+#ifdef RE_ENABLE_I18N
+static void optimize_utf8 (re_dfa_t *dfa);
+#endif
+static reg_errcode_t analyze (regex_t *preg);
+static reg_errcode_t preorder (bin_tree_t *root,
+			       reg_errcode_t (fn (void *, bin_tree_t *)),
+			       void *extra);
+static reg_errcode_t postorder (bin_tree_t *root,
+				reg_errcode_t (fn (void *, bin_tree_t *)),
+				void *extra);
+static reg_errcode_t optimize_subexps (void *extra, bin_tree_t *node);
+static reg_errcode_t lower_subexps (void *extra, bin_tree_t *node);
+static bin_tree_t *lower_subexp (reg_errcode_t *err, regex_t *preg,
+				 bin_tree_t *node);
+static reg_errcode_t calc_first (void *extra, bin_tree_t *node);
+static reg_errcode_t calc_next (void *extra, bin_tree_t *node);
+static reg_errcode_t link_nfa_nodes (void *extra, bin_tree_t *node);
+static int duplicate_node (re_dfa_t *dfa, int org_idx, unsigned int constraint);
+static int search_duplicated_node (const re_dfa_t *dfa, int org_node,
+				   unsigned int constraint);
+static reg_errcode_t calc_eclosure (re_dfa_t *dfa);
+static reg_errcode_t calc_eclosure_iter (re_node_set *new_set, re_dfa_t *dfa,
+					 int node, int root);
+static reg_errcode_t calc_inveclosure (re_dfa_t *dfa);
+static int fetch_number (re_string_t *input, re_token_t *token,
+			 reg_syntax_t syntax);
+static int peek_token (re_token_t *token, re_string_t *input,
+			reg_syntax_t syntax) internal_function;
+static bin_tree_t *parse (re_string_t *regexp, regex_t *preg,
+			  reg_syntax_t syntax, reg_errcode_t *err);
+static bin_tree_t *parse_reg_exp (re_string_t *regexp, regex_t *preg,
+				  re_token_t *token, reg_syntax_t syntax,
+				  int nest, reg_errcode_t *err);
+static bin_tree_t *parse_branch (re_string_t *regexp, regex_t *preg,
+				 re_token_t *token, reg_syntax_t syntax,
+				 int nest, reg_errcode_t *err);
+static bin_tree_t *parse_expression (re_string_t *regexp, regex_t *preg,
+				     re_token_t *token, reg_syntax_t syntax,
+				     int nest, reg_errcode_t *err);
+static bin_tree_t *parse_sub_exp (re_string_t *regexp, regex_t *preg,
+				  re_token_t *token, reg_syntax_t syntax,
+				  int nest, reg_errcode_t *err);
+static bin_tree_t *parse_dup_op (bin_tree_t *dup_elem, re_string_t *regexp,
+				 re_dfa_t *dfa, re_token_t *token,
+				 reg_syntax_t syntax, reg_errcode_t *err);
+static bin_tree_t *parse_bracket_exp (re_string_t *regexp, re_dfa_t *dfa,
+				      re_token_t *token, reg_syntax_t syntax,
+				      reg_errcode_t *err);
+static reg_errcode_t parse_bracket_element (bracket_elem_t *elem,
+					    re_string_t *regexp,
+					    re_token_t *token, int token_len,
+					    re_dfa_t *dfa,
+					    reg_syntax_t syntax,
+					    int accept_hyphen);
+static reg_errcode_t parse_bracket_symbol (bracket_elem_t *elem,
+					  re_string_t *regexp,
+					  re_token_t *token);
+#ifdef RE_ENABLE_I18N
+static reg_errcode_t build_equiv_class (bitset_t sbcset,
+					re_charset_t *mbcset,
+					int *equiv_class_alloc,
+					const unsigned char *name);
+static reg_errcode_t build_charclass (RE_TRANSLATE_TYPE trans,
+				      bitset_t sbcset,
+				      re_charset_t *mbcset,
+				      int *char_class_alloc,
+				      const unsigned char *class_name,
+				      reg_syntax_t syntax);
+#else  /* not RE_ENABLE_I18N */
+static reg_errcode_t build_equiv_class (bitset_t sbcset,
+					const unsigned char *name);
+static reg_errcode_t build_charclass (RE_TRANSLATE_TYPE trans,
+				      bitset_t sbcset,
+				      const unsigned char *class_name,
+				      reg_syntax_t syntax);
+#endif /* not RE_ENABLE_I18N */
+static bin_tree_t *build_charclass_op (re_dfa_t *dfa,
+				       RE_TRANSLATE_TYPE trans,
+				       const unsigned char *class_name,
+				       const unsigned char *extra,
+				       int non_match, reg_errcode_t *err);
+static bin_tree_t *create_tree (re_dfa_t *dfa,
+				bin_tree_t *left, bin_tree_t *right,
+				re_token_type_t type);
+static bin_tree_t *create_token_tree (re_dfa_t *dfa,
+				      bin_tree_t *left, bin_tree_t *right,
+				      const re_token_t *token);
+static bin_tree_t *duplicate_tree (const bin_tree_t *src, re_dfa_t *dfa);
+static void free_token (re_token_t *node);
+static reg_errcode_t free_tree (void *extra, bin_tree_t *node);
+static reg_errcode_t mark_opt_subexp (void *extra, bin_tree_t *node);
+
+/* This table gives an error message for each of the error codes listed
+   in regex.h.  Obviously the order here has to be same as there.
+   POSIX doesn't require that we do anything for REG_NOERROR,
+   but why not be nice?  */
+
+const char __re_error_msgid[] attribute_hidden =
+  {
+#define REG_NOERROR_IDX	0
+    gettext_noop ("Success")	/* REG_NOERROR */
+    "\0"
+#define REG_NOMATCH_IDX (REG_NOERROR_IDX + sizeof "Success")
+    gettext_noop ("No match")	/* REG_NOMATCH */
+    "\0"
+#define REG_BADPAT_IDX	(REG_NOMATCH_IDX + sizeof "No match")
+    gettext_noop ("Invalid regular expression") /* REG_BADPAT */
+    "\0"
+#define REG_ECOLLATE_IDX (REG_BADPAT_IDX + sizeof "Invalid regular expression")
+    gettext_noop ("Invalid collation character") /* REG_ECOLLATE */
+    "\0"
+#define REG_ECTYPE_IDX	(REG_ECOLLATE_IDX + sizeof "Invalid collation character")
+    gettext_noop ("Invalid character class name") /* REG_ECTYPE */
+    "\0"
+#define REG_EESCAPE_IDX	(REG_ECTYPE_IDX + sizeof "Invalid character class name")
+    gettext_noop ("Trailing backslash") /* REG_EESCAPE */
+    "\0"
+#define REG_ESUBREG_IDX	(REG_EESCAPE_IDX + sizeof "Trailing backslash")
+    gettext_noop ("Invalid back reference") /* REG_ESUBREG */
+    "\0"
+#define REG_EBRACK_IDX	(REG_ESUBREG_IDX + sizeof "Invalid back reference")
+    gettext_noop ("Unmatched [ or [^")	/* REG_EBRACK */
+    "\0"
+#define REG_EPAREN_IDX	(REG_EBRACK_IDX + sizeof "Unmatched [ or [^")
+    gettext_noop ("Unmatched ( or \\(") /* REG_EPAREN */
+    "\0"
+#define REG_EBRACE_IDX	(REG_EPAREN_IDX + sizeof "Unmatched ( or \\(")
+    gettext_noop ("Unmatched \\{") /* REG_EBRACE */
+    "\0"
+#define REG_BADBR_IDX	(REG_EBRACE_IDX + sizeof "Unmatched \\{")
+    gettext_noop ("Invalid content of \\{\\}") /* REG_BADBR */
+    "\0"
+#define REG_ERANGE_IDX	(REG_BADBR_IDX + sizeof "Invalid content of \\{\\}")
+    gettext_noop ("Invalid range end")	/* REG_ERANGE */
+    "\0"
+#define REG_ESPACE_IDX	(REG_ERANGE_IDX + sizeof "Invalid range end")
+    gettext_noop ("Memory exhausted") /* REG_ESPACE */
+    "\0"
+#define REG_BADRPT_IDX	(REG_ESPACE_IDX + sizeof "Memory exhausted")
+    gettext_noop ("Invalid preceding regular expression") /* REG_BADRPT */
+    "\0"
+#define REG_EEND_IDX	(REG_BADRPT_IDX + sizeof "Invalid preceding regular expression")
+    gettext_noop ("Premature end of regular expression") /* REG_EEND */
+    "\0"
+#define REG_ESIZE_IDX	(REG_EEND_IDX + sizeof "Premature end of regular expression")
+    gettext_noop ("Regular expression too big") /* REG_ESIZE */
+    "\0"
+#define REG_ERPAREN_IDX	(REG_ESIZE_IDX + sizeof "Regular expression too big")
+    gettext_noop ("Unmatched ) or \\)") /* REG_ERPAREN */
+  };
+
+const size_t __re_error_msgid_idx[] attribute_hidden =
+  {
+    REG_NOERROR_IDX,
+    REG_NOMATCH_IDX,
+    REG_BADPAT_IDX,
+    REG_ECOLLATE_IDX,
+    REG_ECTYPE_IDX,
+    REG_EESCAPE_IDX,
+    REG_ESUBREG_IDX,
+    REG_EBRACK_IDX,
+    REG_EPAREN_IDX,
+    REG_EBRACE_IDX,
+    REG_BADBR_IDX,
+    REG_ERANGE_IDX,
+    REG_ESPACE_IDX,
+    REG_BADRPT_IDX,
+    REG_EEND_IDX,
+    REG_ESIZE_IDX,
+    REG_ERPAREN_IDX
+  };
+
+/* Entry points for GNU code.  */
+
+/* re_compile_pattern is the GNU regular expression compiler: it
+   compiles PATTERN (of length LENGTH) and puts the result in BUFP.
+   Returns 0 if the pattern was valid, otherwise an error string.
+
+   Assumes the `allocated' (and perhaps `buffer') and `translate' fields
+   are set in BUFP on entry.  */
+
+const char *
+re_compile_pattern (pattern, length, bufp)
+    const char *pattern;
+    size_t length;
+    struct re_pattern_buffer *bufp;
+{
+  reg_errcode_t ret;
+
+  /* And GNU code determines whether or not to get register information
+     by passing null for the REGS argument to re_match, etc., not by
+     setting no_sub, unless RE_NO_SUB is set.  */
+  bufp->no_sub = !!(re_syntax_options & RE_NO_SUB);
+
+  /* Match anchors at newline.  */
+  bufp->newline_anchor = 1;
+
+  ret = re_compile_internal (bufp, pattern, length, re_syntax_options);
+
+  if (!ret)
+    return NULL;
+  return gettext (__re_error_msgid + __re_error_msgid_idx[(int) ret]);
+}
+#ifdef _LIBC
+weak_alias (__re_compile_pattern, re_compile_pattern)
+#endif
+
+/* Set by `re_set_syntax' to the current regexp syntax to recognize.  Can
+   also be assigned to arbitrarily: each pattern buffer stores its own
+   syntax, so it can be changed between regex compilations.  */
+/* This has no initializer because initialized variables in Emacs
+   become read-only after dumping.  */
+reg_syntax_t re_syntax_options;
+
+
+/* Specify the precise syntax of regexps for compilation.  This provides
+   for compatibility for various utilities which historically have
+   different, incompatible syntaxes.
+
+   The argument SYNTAX is a bit mask comprised of the various bits
+   defined in regex.h.  We return the old syntax.  */
+
+reg_syntax_t
+re_set_syntax (syntax)
+    reg_syntax_t syntax;
+{
+  reg_syntax_t ret = re_syntax_options;
+
+  re_syntax_options = syntax;
+  return ret;
+}
+#ifdef _LIBC
+weak_alias (__re_set_syntax, re_set_syntax)
+#endif
+
+int
+re_compile_fastmap (bufp)
+    struct re_pattern_buffer *bufp;
+{
+  re_dfa_t *dfa = (re_dfa_t *) bufp->buffer;
+  char *fastmap = bufp->fastmap;
+
+  memset (fastmap, '\0', sizeof (char) * SBC_MAX);
+  re_compile_fastmap_iter (bufp, dfa->init_state, fastmap);
+  if (dfa->init_state != dfa->init_state_word)
+    re_compile_fastmap_iter (bufp, dfa->init_state_word, fastmap);
+  if (dfa->init_state != dfa->init_state_nl)
+    re_compile_fastmap_iter (bufp, dfa->init_state_nl, fastmap);
+  if (dfa->init_state != dfa->init_state_begbuf)
+    re_compile_fastmap_iter (bufp, dfa->init_state_begbuf, fastmap);
+  bufp->fastmap_accurate = 1;
+  return 0;
+}
+#ifdef _LIBC
+weak_alias (__re_compile_fastmap, re_compile_fastmap)
+#endif
+
+static inline void
+__attribute ((always_inline))
+re_set_fastmap (char *fastmap, int icase, int ch)
+{
+  fastmap[ch] = 1;
+  if (icase)
+    fastmap[tolower (ch)] = 1;
+}
+
+/* Helper function for re_compile_fastmap.
+   Compile fastmap for the initial_state INIT_STATE.  */
+
+static void
+re_compile_fastmap_iter (regex_t *bufp, const re_dfastate_t *init_state,
+			 char *fastmap)
+{
+  re_dfa_t *dfa = (re_dfa_t *) bufp->buffer;
+  int node_cnt;
+  int icase = (dfa->mb_cur_max == 1 && (bufp->syntax & RE_ICASE));
+  for (node_cnt = 0; node_cnt < init_state->nodes.nelem; ++node_cnt)
+    {
+      int node = init_state->nodes.elems[node_cnt];
+      re_token_type_t type = dfa->nodes[node].type;
+
+      if (type == CHARACTER)
+	{
+	  re_set_fastmap (fastmap, icase, dfa->nodes[node].opr.c);
+#ifdef RE_ENABLE_I18N
+	  if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
+	    {
+	      unsigned char *buf = alloca (dfa->mb_cur_max), *p;
+	      wchar_t wc;
+	      mbstate_t state;
+
+	      p = buf;
+	      *p++ = dfa->nodes[node].opr.c;
+	      while (++node < dfa->nodes_len
+		     &&	dfa->nodes[node].type == CHARACTER
+		     && dfa->nodes[node].mb_partial)
+		*p++ = dfa->nodes[node].opr.c;
+	      memset (&state, '\0', sizeof (state));
+	      if (mbrtowc (&wc, (const char *) buf, p - buf,
+			   &state) == p - buf
+		  && (__wcrtomb ((char *) buf, towlower (wc), &state)
+		      != (size_t) -1))
+		re_set_fastmap (fastmap, 0, buf[0]);
+	    }
+#endif
+	}
+      else if (type == SIMPLE_BRACKET)
+	{
+	  int i, ch;
+	  for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
+	    {
+	      int j;
+	      bitset_word_t w = dfa->nodes[node].opr.sbcset[i];
+	      for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
+		if (w & ((bitset_word_t) 1 << j))
+		  re_set_fastmap (fastmap, icase, ch);
+	    }
+	}
+#ifdef RE_ENABLE_I18N
+      else if (type == COMPLEX_BRACKET)
+	{
+	  int i;
+	  re_charset_t *cset = dfa->nodes[node].opr.mbcset;
+	  if (cset->non_match || cset->ncoll_syms || cset->nequiv_classes
+	      || cset->nranges || cset->nchar_classes)
+	    {
+# ifdef _LIBC
+	      if (_NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES) != 0)
+		{
+		  /* In this case we want to catch the bytes which are
+		     the first byte of any collation elements.
+		     e.g. In da_DK, we want to catch 'a' since "aa"
+			  is a valid collation element, and don't catch
+			  'b' since 'b' is the only collation element
+			  which starts from 'b'.  */
+		  const int32_t *table = (const int32_t *)
+		    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
+		  for (i = 0; i < SBC_MAX; ++i)
+		    if (table[i] < 0)
+		      re_set_fastmap (fastmap, icase, i);
+		}
+# else
+	      if (dfa->mb_cur_max > 1)
+		for (i = 0; i < SBC_MAX; ++i)
+		  if (__btowc (i) == WEOF)
+		    re_set_fastmap (fastmap, icase, i);
+# endif /* not _LIBC */
+	    }
+	  for (i = 0; i < cset->nmbchars; ++i)
+	    {
+	      char buf[256];
+	      mbstate_t state;
+	      memset (&state, '\0', sizeof (state));
+	      if (__wcrtomb (buf, cset->mbchars[i], &state) != (size_t) -1)
+		re_set_fastmap (fastmap, icase, *(unsigned char *) buf);
+	      if ((bufp->syntax & RE_ICASE) && dfa->mb_cur_max > 1)
+		{
+		  if (__wcrtomb (buf, towlower (cset->mbchars[i]), &state)
+		      != (size_t) -1)
+		    re_set_fastmap (fastmap, 0, *(unsigned char *) buf);
+		}
+	    }
+	}
+#endif /* RE_ENABLE_I18N */
+      else if (type == OP_PERIOD
+#ifdef RE_ENABLE_I18N
+	       || type == OP_UTF8_PERIOD
+#endif /* RE_ENABLE_I18N */
+	       || type == END_OF_RE)
+	{
+	  memset (fastmap, '\1', sizeof (char) * SBC_MAX);
+	  if (type == END_OF_RE)
+	    bufp->can_be_null = 1;
+	  return;
+	}
+    }
+}
+
+/* Entry point for POSIX code.  */
+/* regcomp takes a regular expression as a string and compiles it.
+
+   PREG is a regex_t *.  We do not expect any fields to be initialized,
+   since POSIX says we shouldn't.  Thus, we set
+
+     `buffer' to the compiled pattern;
+     `used' to the length of the compiled pattern;
+     `syntax' to RE_SYNTAX_POSIX_EXTENDED if the
+       REG_EXTENDED bit in CFLAGS is set; otherwise, to
+       RE_SYNTAX_POSIX_BASIC;
+     `newline_anchor' to REG_NEWLINE being set in CFLAGS;
+     `fastmap' to an allocated space for the fastmap;
+     `fastmap_accurate' to zero;
+     `re_nsub' to the number of subexpressions in PATTERN.
+
+   PATTERN is the address of the pattern string.
+
+   CFLAGS is a series of bits which affect compilation.
+
+     If REG_EXTENDED is set, we use POSIX extended syntax; otherwise, we
+     use POSIX basic syntax.
+
+     If REG_NEWLINE is set, then . and [^...] don't match newline.
+     Also, regexec will try a match beginning after every newline.
+
+     If REG_ICASE is set, then we considers upper- and lowercase
+     versions of letters to be equivalent when matching.
+
+     If REG_NOSUB is set, then when PREG is passed to regexec, that
+     routine will report only success or failure, and nothing about the
+     registers.
+
+   It returns 0 if it succeeds, nonzero if it doesn't.  (See regex.h for
+   the return codes and their meanings.)  */
+
+int
+regcomp (preg, pattern, cflags)
+    regex_t *__restrict preg;
+    const char *__restrict pattern;
+    int cflags;
+{
+  reg_errcode_t ret;
+  reg_syntax_t syntax = ((cflags & REG_EXTENDED) ? RE_SYNTAX_POSIX_EXTENDED
+			 : RE_SYNTAX_POSIX_BASIC);
+
+  preg->buffer = NULL;
+  preg->allocated = 0;
+  preg->used = 0;
+
+  /* Try to allocate space for the fastmap.  */
+  preg->fastmap = re_malloc (char, SBC_MAX);
+  if (BE (preg->fastmap == NULL, 0))
+    return REG_ESPACE;
+
+  syntax |= (cflags & REG_ICASE) ? RE_ICASE : 0;
+
+  /* If REG_NEWLINE is set, newlines are treated differently.  */
+  if (cflags & REG_NEWLINE)
+    { /* REG_NEWLINE implies neither . nor [^...] match newline.  */
+      syntax &= ~RE_DOT_NEWLINE;
+      syntax |= RE_HAT_LISTS_NOT_NEWLINE;
+      /* It also changes the matching behavior.  */
+      preg->newline_anchor = 1;
+    }
+  else
+    preg->newline_anchor = 0;
+  preg->no_sub = !!(cflags & REG_NOSUB);
+  preg->translate = NULL;
+
+  ret = re_compile_internal (preg, pattern, strlen (pattern), syntax);
+
+  /* POSIX doesn't distinguish between an unmatched open-group and an
+     unmatched close-group: both are REG_EPAREN.  */
+  if (ret == REG_ERPAREN)
+    ret = REG_EPAREN;
+
+  /* We have already checked preg->fastmap != NULL.  */
+  if (BE (ret == REG_NOERROR, 1))
+    /* Compute the fastmap now, since regexec cannot modify the pattern
+       buffer.  This function never fails in this implementation.  */
+    (void) re_compile_fastmap (preg);
+  else
+    {
+      /* Some error occurred while compiling the expression.  */
+      re_free (preg->fastmap);
+      preg->fastmap = NULL;
+    }
+
+  return (int) ret;
+}
+#ifdef _LIBC
+weak_alias (__regcomp, regcomp)
+#endif
+
+/* Returns a message corresponding to an error code, ERRCODE, returned
+   from either regcomp or regexec.   We don't use PREG here.  */
+
+size_t
+regerror (errcode, preg, errbuf, errbuf_size)
+    int errcode;
+    const regex_t *__restrict preg;
+    char *__restrict errbuf;
+    size_t errbuf_size;
+{
+  const char *msg;
+  size_t msg_size;
+
+  if (BE (errcode < 0
+	  || errcode >= (int) (sizeof (__re_error_msgid_idx)
+			       / sizeof (__re_error_msgid_idx[0])), 0))
+    /* Only error codes returned by the rest of the code should be passed
+       to this routine.  If we are given anything else, or if other regex
+       code generates an invalid error code, then the program has a bug.
+       Dump core so we can fix it.  */
+    abort ();
+
+  msg = gettext (__re_error_msgid + __re_error_msgid_idx[errcode]);
+
+  msg_size = strlen (msg) + 1; /* Includes the null.  */
+
+  if (BE (errbuf_size != 0, 1))
+    {
+      if (BE (msg_size > errbuf_size, 0))
+	{
+#if defined HAVE_MEMPCPY || defined _LIBC
+	  *((char *) __mempcpy (errbuf, msg, errbuf_size - 1)) = '\0';
+#else
+	  memcpy (errbuf, msg, errbuf_size - 1);
+	  errbuf[errbuf_size - 1] = 0;
+#endif
+	}
+      else
+	memcpy (errbuf, msg, msg_size);
+    }
+
+  return msg_size;
+}
+#ifdef _LIBC
+weak_alias (__regerror, regerror)
+#endif
+
+
+#ifdef RE_ENABLE_I18N
+/* This static array is used for the map to single-byte characters when
+   UTF-8 is used.  Otherwise we would allocate memory just to initialize
+   it the same all the time.  UTF-8 is the preferred encoding so this is
+   a worthwhile optimization.  */
+static const bitset_t utf8_sb_map =
+{
+  /* Set the first 128 bits.  */
+  [0 ... 0x80 / BITSET_WORD_BITS - 1] = BITSET_WORD_MAX
+};
+#endif
+
+
+static void
+free_dfa_content (re_dfa_t *dfa)
+{
+  int i, j;
+
+  if (dfa->nodes)
+    for (i = 0; i < dfa->nodes_len; ++i)
+      free_token (dfa->nodes + i);
+  re_free (dfa->nexts);
+  for (i = 0; i < dfa->nodes_len; ++i)
+    {
+      if (dfa->eclosures != NULL)
+	re_node_set_free (dfa->eclosures + i);
+      if (dfa->inveclosures != NULL)
+	re_node_set_free (dfa->inveclosures + i);
+      if (dfa->edests != NULL)
+	re_node_set_free (dfa->edests + i);
+    }
+  re_free (dfa->edests);
+  re_free (dfa->eclosures);
+  re_free (dfa->inveclosures);
+  re_free (dfa->nodes);
+
+  if (dfa->state_table)
+    for (i = 0; i <= dfa->state_hash_mask; ++i)
+      {
+	struct re_state_table_entry *entry = dfa->state_table + i;
+	for (j = 0; j < entry->num; ++j)
+	  {
+	    re_dfastate_t *state = entry->array[j];
+	    free_state (state);
+	  }
+        re_free (entry->array);
+      }
+  re_free (dfa->state_table);
+#ifdef RE_ENABLE_I18N
+  if (dfa->sb_char != utf8_sb_map)
+    re_free (dfa->sb_char);
+#endif
+  re_free (dfa->subexp_map);
+#ifdef DEBUG
+  re_free (dfa->re_str);
+#endif
+
+  re_free (dfa);
+}
+
+
+/* Free dynamically allocated space used by PREG.  */
+
+void
+regfree (preg)
+    regex_t *preg;
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  if (BE (dfa != NULL, 1))
+    free_dfa_content (dfa);
+  preg->buffer = NULL;
+  preg->allocated = 0;
+
+  re_free (preg->fastmap);
+  preg->fastmap = NULL;
+
+  re_free (preg->translate);
+  preg->translate = NULL;
+}
+#ifdef _LIBC
+weak_alias (__regfree, regfree)
+#endif
+
+/* Entry points compatible with 4.2 BSD regex library.  We don't define
+   them unless specifically requested.  */
+
+#if defined _REGEX_RE_COMP || defined _LIBC
+
+/* BSD has one and only one pattern buffer.  */
+static struct re_pattern_buffer re_comp_buf;
+
+char *
+# ifdef _LIBC
+/* Make these definitions weak in libc, so POSIX programs can redefine
+   these names if they don't use our functions, and still use
+   regcomp/regexec above without link errors.  */
+weak_function
+# endif
+re_comp (s)
+     const char *s;
+{
+  reg_errcode_t ret;
+  char *fastmap;
+
+  if (!s)
+    {
+      if (!re_comp_buf.buffer)
+	return gettext ("No previous regular expression");
+      return 0;
+    }
+
+  if (re_comp_buf.buffer)
+    {
+      fastmap = re_comp_buf.fastmap;
+      re_comp_buf.fastmap = NULL;
+      __regfree (&re_comp_buf);
+      memset (&re_comp_buf, '\0', sizeof (re_comp_buf));
+      re_comp_buf.fastmap = fastmap;
+    }
+
+  if (re_comp_buf.fastmap == NULL)
+    {
+      re_comp_buf.fastmap = (char *) malloc (SBC_MAX);
+      if (re_comp_buf.fastmap == NULL)
+	return (char *) gettext (__re_error_msgid
+				 + __re_error_msgid_idx[(int) REG_ESPACE]);
+    }
+
+  /* Since `re_exec' always passes NULL for the `regs' argument, we
+     don't need to initialize the pattern buffer fields which affect it.  */
+
+  /* Match anchors at newlines.  */
+  re_comp_buf.newline_anchor = 1;
+
+  ret = re_compile_internal (&re_comp_buf, s, strlen (s), re_syntax_options);
+
+  if (!ret)
+    return NULL;
+
+  /* Yes, we're discarding `const' here if !HAVE_LIBINTL.  */
+  return (char *) gettext (__re_error_msgid + __re_error_msgid_idx[(int) ret]);
+}
+
+#ifdef _LIBC
+libc_freeres_fn (free_mem)
+{
+  __regfree (&re_comp_buf);
+}
+#endif
+
+#endif /* _REGEX_RE_COMP */
+
+/* Internal entry point.
+   Compile the regular expression PATTERN, whose length is LENGTH.
+   SYNTAX indicate regular expression's syntax.  */
+
+static reg_errcode_t
+re_compile_internal (regex_t *preg, const char * pattern, size_t length,
+		     reg_syntax_t syntax)
+{
+  reg_errcode_t err = REG_NOERROR;
+  re_dfa_t *dfa;
+  re_string_t regexp;
+
+  /* Initialize the pattern buffer.  */
+  preg->fastmap_accurate = 0;
+  preg->syntax = syntax;
+  preg->not_bol = preg->not_eol = 0;
+  preg->used = 0;
+  preg->re_nsub = 0;
+  preg->can_be_null = 0;
+  preg->regs_allocated = REGS_UNALLOCATED;
+
+  /* Initialize the dfa.  */
+  dfa = (re_dfa_t *) preg->buffer;
+  if (BE (preg->allocated < sizeof (re_dfa_t), 0))
+    {
+      /* If zero allocated, but buffer is non-null, try to realloc
+	 enough space.  This loses if buffer's address is bogus, but
+	 that is the user's responsibility.  If ->buffer is NULL this
+	 is a simple allocation.  */
+      dfa = re_realloc (preg->buffer, re_dfa_t, 1);
+      if (dfa == NULL)
+	return REG_ESPACE;
+      preg->allocated = sizeof (re_dfa_t);
+      preg->buffer = (unsigned char *) dfa;
+    }
+  preg->used = sizeof (re_dfa_t);
+
+  err = init_dfa (dfa, length);
+  if (BE (err != REG_NOERROR, 0))
+    {
+      free_dfa_content (dfa);
+      preg->buffer = NULL;
+      preg->allocated = 0;
+      return err;
+    }
+#ifdef DEBUG
+  /* Note: length+1 will not overflow since it is checked in init_dfa.  */
+  dfa->re_str = re_malloc (char, length + 1);
+  strncpy (dfa->re_str, pattern, length + 1);
+#endif
+
+  __libc_lock_init (dfa->lock);
+
+  err = re_string_construct (&regexp, pattern, length, preg->translate,
+			     syntax & RE_ICASE, dfa);
+  if (BE (err != REG_NOERROR, 0))
+    {
+    re_compile_internal_free_return:
+      free_workarea_compile (preg);
+      re_string_destruct (&regexp);
+      free_dfa_content (dfa);
+      preg->buffer = NULL;
+      preg->allocated = 0;
+      return err;
+    }
+
+  /* Parse the regular expression, and build a structure tree.  */
+  preg->re_nsub = 0;
+  dfa->str_tree = parse (&regexp, preg, syntax, &err);
+  if (BE (dfa->str_tree == NULL, 0))
+    goto re_compile_internal_free_return;
+
+  /* Analyze the tree and create the nfa.  */
+  err = analyze (preg);
+  if (BE (err != REG_NOERROR, 0))
+    goto re_compile_internal_free_return;
+
+#ifdef RE_ENABLE_I18N
+  /* If possible, do searching in single byte encoding to speed things up.  */
+  if (dfa->is_utf8 && !(syntax & RE_ICASE) && preg->translate == NULL)
+    optimize_utf8 (dfa);
+#endif
+
+  /* Then create the initial state of the dfa.  */
+  err = create_initial_state (dfa);
+
+  /* Release work areas.  */
+  free_workarea_compile (preg);
+  re_string_destruct (&regexp);
+
+  if (BE (err != REG_NOERROR, 0))
+    {
+      free_dfa_content (dfa);
+      preg->buffer = NULL;
+      preg->allocated = 0;
+    }
+
+  return err;
+}
+
+/* Initialize DFA.  We use the length of the regular expression PAT_LEN
+   as the initial length of some arrays.  */
+
+static reg_errcode_t
+init_dfa (re_dfa_t *dfa, size_t pat_len)
+{
+  unsigned int table_size;
+#ifndef _LIBC
+  char *codeset_name;
+#endif
+
+  memset (dfa, '\0', sizeof (re_dfa_t));
+
+  /* Force allocation of str_tree_storage the first time.  */
+  dfa->str_tree_storage_idx = BIN_TREE_STORAGE_SIZE;
+
+  /* Avoid overflows.  */
+  if (pat_len == SIZE_MAX)
+    return REG_ESPACE;
+
+  dfa->nodes_alloc = pat_len + 1;
+  dfa->nodes = re_malloc (re_token_t, dfa->nodes_alloc);
+
+  /*  table_size = 2 ^ ceil(log pat_len) */
+  for (table_size = 1; ; table_size <<= 1)
+    if (table_size > pat_len)
+      break;
+
+  dfa->state_table = calloc (sizeof (struct re_state_table_entry), table_size);
+  dfa->state_hash_mask = table_size - 1;
+
+  dfa->mb_cur_max = MB_CUR_MAX;
+#ifdef _LIBC
+  if (dfa->mb_cur_max == 6
+      && strcmp (_NL_CURRENT (LC_CTYPE, _NL_CTYPE_CODESET_NAME), "UTF-8") == 0)
+    dfa->is_utf8 = 1;
+  dfa->map_notascii = (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MAP_TO_NONASCII)
+		       != 0);
+#else
+# ifdef HAVE_LANGINFO_CODESET
+  codeset_name = nl_langinfo (CODESET);
+# else
+  codeset_name = getenv ("LC_ALL");
+  if (codeset_name == NULL || codeset_name[0] == '\0')
+    codeset_name = getenv ("LC_CTYPE");
+  if (codeset_name == NULL || codeset_name[0] == '\0')
+    codeset_name = getenv ("LANG");
+  if (codeset_name == NULL)
+    codeset_name = "";
+  else if (strchr (codeset_name, '.') !=  NULL)
+    codeset_name = strchr (codeset_name, '.') + 1;
+# endif
+
+  if (strcasecmp (codeset_name, "UTF-8") == 0
+      || strcasecmp (codeset_name, "UTF8") == 0)
+    dfa->is_utf8 = 1;
+
+  /* We check exhaustively in the loop below if this charset is a
+     superset of ASCII.  */
+  dfa->map_notascii = 0;
+#endif
+
+#ifdef RE_ENABLE_I18N
+  if (dfa->mb_cur_max > 1)
+    {
+      if (dfa->is_utf8)
+	dfa->sb_char = (re_bitset_ptr_t) utf8_sb_map;
+      else
+	{
+	  int i, j, ch;
+
+	  dfa->sb_char = (re_bitset_ptr_t) calloc (sizeof (bitset_t), 1);
+	  if (BE (dfa->sb_char == NULL, 0))
+	    return REG_ESPACE;
+
+	  /* Set the bits corresponding to single byte chars.  */
+	  for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
+	    for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
+	      {
+		wint_t wch = __btowc (ch);
+		if (wch != WEOF)
+		  dfa->sb_char[i] |= (bitset_word_t) 1 << j;
+# ifndef _LIBC
+		if (isascii (ch) && wch != ch)
+		  dfa->map_notascii = 1;
+# endif
+	      }
+	}
+    }
+#endif
+
+  if (BE (dfa->nodes == NULL || dfa->state_table == NULL, 0))
+    return REG_ESPACE;
+  return REG_NOERROR;
+}
+
+/* Initialize WORD_CHAR table, which indicate which character is
+   "word".  In this case "word" means that it is the word construction
+   character used by some operators like "\<", "\>", etc.  */
+
+static void
+internal_function
+init_word_char (re_dfa_t *dfa)
+{
+  int i, j, ch;
+  dfa->word_ops_used = 1;
+  for (i = 0, ch = 0; i < BITSET_WORDS; ++i)
+    for (j = 0; j < BITSET_WORD_BITS; ++j, ++ch)
+      if (isalnum (ch) || ch == '_')
+	dfa->word_char[i] |= (bitset_word_t) 1 << j;
+}
+
+/* Free the work area which are only used while compiling.  */
+
+static void
+free_workarea_compile (regex_t *preg)
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  bin_tree_storage_t *storage, *next;
+  for (storage = dfa->str_tree_storage; storage; storage = next)
+    {
+      next = storage->next;
+      re_free (storage);
+    }
+  dfa->str_tree_storage = NULL;
+  dfa->str_tree_storage_idx = BIN_TREE_STORAGE_SIZE;
+  dfa->str_tree = NULL;
+  re_free (dfa->org_indices);
+  dfa->org_indices = NULL;
+}
+
+/* Create initial states for all contexts.  */
+
+static reg_errcode_t
+create_initial_state (re_dfa_t *dfa)
+{
+  int first, i;
+  reg_errcode_t err;
+  re_node_set init_nodes;
+
+  /* Initial states have the epsilon closure of the node which is
+     the first node of the regular expression.  */
+  first = dfa->str_tree->first->node_idx;
+  dfa->init_node = first;
+  err = re_node_set_init_copy (&init_nodes, dfa->eclosures + first);
+  if (BE (err != REG_NOERROR, 0))
+    return err;
+
+  /* The back-references which are in initial states can epsilon transit,
+     since in this case all of the subexpressions can be null.
+     Then we add epsilon closures of the nodes which are the next nodes of
+     the back-references.  */
+  if (dfa->nbackref > 0)
+    for (i = 0; i < init_nodes.nelem; ++i)
+      {
+	int node_idx = init_nodes.elems[i];
+	re_token_type_t type = dfa->nodes[node_idx].type;
+
+	int clexp_idx;
+	if (type != OP_BACK_REF)
+	  continue;
+	for (clexp_idx = 0; clexp_idx < init_nodes.nelem; ++clexp_idx)
+	  {
+	    re_token_t *clexp_node;
+	    clexp_node = dfa->nodes + init_nodes.elems[clexp_idx];
+	    if (clexp_node->type == OP_CLOSE_SUBEXP
+		&& clexp_node->opr.idx == dfa->nodes[node_idx].opr.idx)
+	      break;
+	  }
+	if (clexp_idx == init_nodes.nelem)
+	  continue;
+
+	if (type == OP_BACK_REF)
+	  {
+	    int dest_idx = dfa->edests[node_idx].elems[0];
+	    if (!re_node_set_contains (&init_nodes, dest_idx))
+	      {
+		re_node_set_merge (&init_nodes, dfa->eclosures + dest_idx);
+		i = 0;
+	      }
+	  }
+      }
+
+  /* It must be the first time to invoke acquire_state.  */
+  dfa->init_state = re_acquire_state_context (&err, dfa, &init_nodes, 0);
+  /* We don't check ERR here, since the initial state must not be NULL.  */
+  if (BE (dfa->init_state == NULL, 0))
+    return err;
+  if (dfa->init_state->has_constraint)
+    {
+      dfa->init_state_word = re_acquire_state_context (&err, dfa, &init_nodes,
+						       CONTEXT_WORD);
+      dfa->init_state_nl = re_acquire_state_context (&err, dfa, &init_nodes,
+						     CONTEXT_NEWLINE);
+      dfa->init_state_begbuf = re_acquire_state_context (&err, dfa,
+							 &init_nodes,
+							 CONTEXT_NEWLINE
+							 | CONTEXT_BEGBUF);
+      if (BE (dfa->init_state_word == NULL || dfa->init_state_nl == NULL
+	      || dfa->init_state_begbuf == NULL, 0))
+	return err;
+    }
+  else
+    dfa->init_state_word = dfa->init_state_nl
+      = dfa->init_state_begbuf = dfa->init_state;
+
+  re_node_set_free (&init_nodes);
+  return REG_NOERROR;
+}
+
+#ifdef RE_ENABLE_I18N
+/* If it is possible to do searching in single byte encoding instead of UTF-8
+   to speed things up, set dfa->mb_cur_max to 1, clear is_utf8 and change
+   DFA nodes where needed.  */
+
+static void
+optimize_utf8 (re_dfa_t *dfa)
+{
+  int node, i, mb_chars = 0, has_period = 0;
+
+  for (node = 0; node < dfa->nodes_len; ++node)
+    switch (dfa->nodes[node].type)
+      {
+      case CHARACTER:
+	if (dfa->nodes[node].opr.c >= 0x80)
+	  mb_chars = 1;
+	break;
+      case ANCHOR:
+	switch (dfa->nodes[node].opr.idx)
+	  {
+	  case LINE_FIRST:
+	  case LINE_LAST:
+	  case BUF_FIRST:
+	  case BUF_LAST:
+	    break;
+	  default:
+	    /* Word anchors etc. cannot be handled.  */
+	    return;
+	  }
+	break;
+      case OP_PERIOD:
+        has_period = 1;
+        break;
+      case OP_BACK_REF:
+      case OP_ALT:
+      case END_OF_RE:
+      case OP_DUP_ASTERISK:
+      case OP_OPEN_SUBEXP:
+      case OP_CLOSE_SUBEXP:
+	break;
+      case COMPLEX_BRACKET:
+	return;
+      case SIMPLE_BRACKET:
+	/* Just double check.  The non-ASCII range starts at 0x80.  */
+	assert (0x80 % BITSET_WORD_BITS == 0);
+        for (i = 0x80 / BITSET_WORD_BITS; i < BITSET_WORDS; ++i)
+	  if (dfa->nodes[node].opr.sbcset[i])
+	    return;
+	break;
+      default:
+	abort ();
+      }
+
+  if (mb_chars || has_period)
+    for (node = 0; node < dfa->nodes_len; ++node)
+      {
+	if (dfa->nodes[node].type == CHARACTER
+	    && dfa->nodes[node].opr.c >= 0x80)
+	  dfa->nodes[node].mb_partial = 0;
+	else if (dfa->nodes[node].type == OP_PERIOD)
+	  dfa->nodes[node].type = OP_UTF8_PERIOD;
+      }
+
+  /* The search can be in single byte locale.  */
+  dfa->mb_cur_max = 1;
+  dfa->is_utf8 = 0;
+  dfa->has_mb_node = dfa->nbackref > 0 || has_period;
+}
+#endif
+
+/* Analyze the structure tree, and calculate "first", "next", "edest",
+   "eclosure", and "inveclosure".  */
+
+static reg_errcode_t
+analyze (regex_t *preg)
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  reg_errcode_t ret;
+
+  /* Allocate arrays.  */
+  dfa->nexts = re_malloc (int, dfa->nodes_alloc);
+  dfa->org_indices = re_malloc (int, dfa->nodes_alloc);
+  dfa->edests = re_malloc (re_node_set, dfa->nodes_alloc);
+  dfa->eclosures = re_malloc (re_node_set, dfa->nodes_alloc);
+  if (BE (dfa->nexts == NULL || dfa->org_indices == NULL || dfa->edests == NULL
+	  || dfa->eclosures == NULL, 0))
+    return REG_ESPACE;
+
+  dfa->subexp_map = re_malloc (int, preg->re_nsub);
+  if (dfa->subexp_map != NULL)
+    {
+      int i;
+      for (i = 0; i < preg->re_nsub; i++)
+	dfa->subexp_map[i] = i;
+      preorder (dfa->str_tree, optimize_subexps, dfa);
+      for (i = 0; i < preg->re_nsub; i++)
+	if (dfa->subexp_map[i] != i)
+	  break;
+      if (i == preg->re_nsub)
+	{
+	  free (dfa->subexp_map);
+	  dfa->subexp_map = NULL;
+	}
+    }
+
+  ret = postorder (dfa->str_tree, lower_subexps, preg);
+  if (BE (ret != REG_NOERROR, 0))
+    return ret;
+  ret = postorder (dfa->str_tree, calc_first, dfa);
+  if (BE (ret != REG_NOERROR, 0))
+    return ret;
+  preorder (dfa->str_tree, calc_next, dfa);
+  ret = preorder (dfa->str_tree, link_nfa_nodes, dfa);
+  if (BE (ret != REG_NOERROR, 0))
+    return ret;
+  ret = calc_eclosure (dfa);
+  if (BE (ret != REG_NOERROR, 0))
+    return ret;
+
+  /* We only need this during the prune_impossible_nodes pass in regexec.c;
+     skip it if p_i_n will not run, as calc_inveclosure can be quadratic.  */
+  if ((!preg->no_sub && preg->re_nsub > 0 && dfa->has_plural_match)
+      || dfa->nbackref)
+    {
+      dfa->inveclosures = re_malloc (re_node_set, dfa->nodes_len);
+      if (BE (dfa->inveclosures == NULL, 0))
+        return REG_ESPACE;
+      ret = calc_inveclosure (dfa);
+    }
+
+  return ret;
+}
+
+/* Our parse trees are very unbalanced, so we cannot use a stack to
+   implement parse tree visits.  Instead, we use parent pointers and
+   some hairy code in these two functions.  */
+static reg_errcode_t
+postorder (bin_tree_t *root, reg_errcode_t (fn (void *, bin_tree_t *)),
+	   void *extra)
+{
+  bin_tree_t *node, *prev;
+
+  for (node = root; ; )
+    {
+      /* Descend down the tree, preferably to the left (or to the right
+	 if that's the only child).  */
+      while (node->left || node->right)
+	if (node->left)
+          node = node->left;
+        else
+          node = node->right;
+
+      do
+	{
+	  reg_errcode_t err = fn (extra, node);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+          if (node->parent == NULL)
+	    return REG_NOERROR;
+	  prev = node;
+	  node = node->parent;
+	}
+      /* Go up while we have a node that is reached from the right.  */
+      while (node->right == prev || node->right == NULL);
+      node = node->right;
+    }
+}
+
+static reg_errcode_t
+preorder (bin_tree_t *root, reg_errcode_t (fn (void *, bin_tree_t *)),
+	  void *extra)
+{
+  bin_tree_t *node;
+
+  for (node = root; ; )
+    {
+      reg_errcode_t err = fn (extra, node);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+
+      /* Go to the left node, or up and to the right.  */
+      if (node->left)
+	node = node->left;
+      else
+	{
+	  bin_tree_t *prev = NULL;
+	  while (node->right == prev || node->right == NULL)
+	    {
+	      prev = node;
+	      node = node->parent;
+	      if (!node)
+	        return REG_NOERROR;
+	    }
+	  node = node->right;
+	}
+    }
+}
+
+/* Optimization pass: if a SUBEXP is entirely contained, strip it and tell
+   re_search_internal to map the inner one's opr.idx to this one's.  Adjust
+   backreferences as well.  Requires a preorder visit.  */
+static reg_errcode_t
+optimize_subexps (void *extra, bin_tree_t *node)
+{
+  re_dfa_t *dfa = (re_dfa_t *) extra;
+
+  if (node->token.type == OP_BACK_REF && dfa->subexp_map)
+    {
+      int idx = node->token.opr.idx;
+      node->token.opr.idx = dfa->subexp_map[idx];
+      dfa->used_bkref_map |= 1 << node->token.opr.idx;
+    }
+
+  else if (node->token.type == SUBEXP
+           && node->left && node->left->token.type == SUBEXP)
+    {
+      int other_idx = node->left->token.opr.idx;
+
+      node->left = node->left->left;
+      if (node->left)
+        node->left->parent = node;
+
+      dfa->subexp_map[other_idx] = dfa->subexp_map[node->token.opr.idx];
+      if (other_idx < BITSET_WORD_BITS)
+	  dfa->used_bkref_map &= ~((bitset_word_t) 1 << other_idx);
+    }
+
+  return REG_NOERROR;
+}
+
+/* Lowering pass: Turn each SUBEXP node into the appropriate concatenation
+   of OP_OPEN_SUBEXP, the body of the SUBEXP (if any) and OP_CLOSE_SUBEXP.  */
+static reg_errcode_t
+lower_subexps (void *extra, bin_tree_t *node)
+{
+  regex_t *preg = (regex_t *) extra;
+  reg_errcode_t err = REG_NOERROR;
+
+  if (node->left && node->left->token.type == SUBEXP)
+    {
+      node->left = lower_subexp (&err, preg, node->left);
+      if (node->left)
+	node->left->parent = node;
+    }
+  if (node->right && node->right->token.type == SUBEXP)
+    {
+      node->right = lower_subexp (&err, preg, node->right);
+      if (node->right)
+	node->right->parent = node;
+    }
+
+  return err;
+}
+
+static bin_tree_t *
+lower_subexp (reg_errcode_t *err, regex_t *preg, bin_tree_t *node)
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  bin_tree_t *body = node->left;
+  bin_tree_t *op, *cls, *tree1, *tree;
+
+  if (preg->no_sub
+      /* We do not optimize empty subexpressions, because otherwise we may
+	 have bad CONCAT nodes with NULL children.  This is obviously not
+	 very common, so we do not lose much.  An example that triggers
+	 this case is the sed "script" /\(\)/x.  */
+      && node->left != NULL
+      && (node->token.opr.idx >= BITSET_WORD_BITS
+	  || !(dfa->used_bkref_map
+	       & ((bitset_word_t) 1 << node->token.opr.idx))))
+    return node->left;
+
+  /* Convert the SUBEXP node to the concatenation of an
+     OP_OPEN_SUBEXP, the contents, and an OP_CLOSE_SUBEXP.  */
+  op = create_tree (dfa, NULL, NULL, OP_OPEN_SUBEXP);
+  cls = create_tree (dfa, NULL, NULL, OP_CLOSE_SUBEXP);
+  tree1 = body ? create_tree (dfa, body, cls, CONCAT) : cls;
+  tree = create_tree (dfa, op, tree1, CONCAT);
+  if (BE (tree == NULL || tree1 == NULL || op == NULL || cls == NULL, 0))
+    {
+      *err = REG_ESPACE;
+      return NULL;
+    }
+
+  op->token.opr.idx = cls->token.opr.idx = node->token.opr.idx;
+  op->token.opt_subexp = cls->token.opt_subexp = node->token.opt_subexp;
+  return tree;
+}
+
+/* Pass 1 in building the NFA: compute FIRST and create unlinked automaton
+   nodes.  Requires a postorder visit.  */
+static reg_errcode_t
+calc_first (void *extra, bin_tree_t *node)
+{
+  re_dfa_t *dfa = (re_dfa_t *) extra;
+  if (node->token.type == CONCAT)
+    {
+      node->first = node->left->first;
+      node->node_idx = node->left->node_idx;
+    }
+  else
+    {
+      node->first = node;
+      node->node_idx = re_dfa_add_node (dfa, node->token);
+      if (BE (node->node_idx == -1, 0))
+        return REG_ESPACE;
+    }
+  return REG_NOERROR;
+}
+
+/* Pass 2: compute NEXT on the tree.  Preorder visit.  */
+static reg_errcode_t
+calc_next (void *extra, bin_tree_t *node)
+{
+  switch (node->token.type)
+    {
+    case OP_DUP_ASTERISK:
+      node->left->next = node;
+      break;
+    case CONCAT:
+      node->left->next = node->right->first;
+      node->right->next = node->next;
+      break;
+    default:
+      if (node->left)
+	node->left->next = node->next;
+      if (node->right)
+        node->right->next = node->next;
+      break;
+    }
+  return REG_NOERROR;
+}
+
+/* Pass 3: link all DFA nodes to their NEXT node (any order will do).  */
+static reg_errcode_t
+link_nfa_nodes (void *extra, bin_tree_t *node)
+{
+  re_dfa_t *dfa = (re_dfa_t *) extra;
+  int idx = node->node_idx;
+  reg_errcode_t err = REG_NOERROR;
+
+  switch (node->token.type)
+    {
+    case CONCAT:
+      break;
+
+    case END_OF_RE:
+      assert (node->next == NULL);
+      break;
+
+    case OP_DUP_ASTERISK:
+    case OP_ALT:
+      {
+	int left, right;
+	dfa->has_plural_match = 1;
+	if (node->left != NULL)
+	  left = node->left->first->node_idx;
+	else
+	  left = node->next->node_idx;
+	if (node->right != NULL)
+	  right = node->right->first->node_idx;
+	else
+	  right = node->next->node_idx;
+	assert (left > -1);
+	assert (right > -1);
+	err = re_node_set_init_2 (dfa->edests + idx, left, right);
+      }
+      break;
+
+    case ANCHOR:
+    case OP_OPEN_SUBEXP:
+    case OP_CLOSE_SUBEXP:
+      err = re_node_set_init_1 (dfa->edests + idx, node->next->node_idx);
+      break;
+
+    case OP_BACK_REF:
+      dfa->nexts[idx] = node->next->node_idx;
+      if (node->token.type == OP_BACK_REF)
+	re_node_set_init_1 (dfa->edests + idx, dfa->nexts[idx]);
+      break;
+
+    default:
+      assert (!IS_EPSILON_NODE (node->token.type));
+      dfa->nexts[idx] = node->next->node_idx;
+      break;
+    }
+
+  return err;
+}
+
+/* Duplicate the epsilon closure of the node ROOT_NODE.
+   Note that duplicated nodes have constraint INIT_CONSTRAINT in addition
+   to their own constraint.  */
+
+static reg_errcode_t
+internal_function
+duplicate_node_closure (re_dfa_t *dfa, int top_org_node, int top_clone_node,
+			int root_node, unsigned int init_constraint)
+{
+  int org_node, clone_node, ret;
+  unsigned int constraint = init_constraint;
+  for (org_node = top_org_node, clone_node = top_clone_node;;)
+    {
+      int org_dest, clone_dest;
+      if (dfa->nodes[org_node].type == OP_BACK_REF)
+	{
+	  /* If the back reference epsilon-transit, its destination must
+	     also have the constraint.  Then duplicate the epsilon closure
+	     of the destination of the back reference, and store it in
+	     edests of the back reference.  */
+	  org_dest = dfa->nexts[org_node];
+	  re_node_set_empty (dfa->edests + clone_node);
+	  clone_dest = duplicate_node (dfa, org_dest, constraint);
+	  if (BE (clone_dest == -1, 0))
+	    return REG_ESPACE;
+	  dfa->nexts[clone_node] = dfa->nexts[org_node];
+	  ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
+	  if (BE (ret < 0, 0))
+	    return REG_ESPACE;
+	}
+      else if (dfa->edests[org_node].nelem == 0)
+	{
+	  /* In case of the node can't epsilon-transit, don't duplicate the
+	     destination and store the original destination as the
+	     destination of the node.  */
+	  dfa->nexts[clone_node] = dfa->nexts[org_node];
+	  break;
+	}
+      else if (dfa->edests[org_node].nelem == 1)
+	{
+	  /* In case of the node can epsilon-transit, and it has only one
+	     destination.  */
+	  org_dest = dfa->edests[org_node].elems[0];
+	  re_node_set_empty (dfa->edests + clone_node);
+	  if (dfa->nodes[org_node].type == ANCHOR)
+	    {
+	      /* In case of the node has another constraint, append it.  */
+	      if (org_node == root_node && clone_node != org_node)
+		{
+		  /* ...but if the node is root_node itself, it means the
+		     epsilon closure have a loop, then tie it to the
+		     destination of the root_node.  */
+		  ret = re_node_set_insert (dfa->edests + clone_node,
+					    org_dest);
+		  if (BE (ret < 0, 0))
+		    return REG_ESPACE;
+		  break;
+		}
+	      constraint |= dfa->nodes[org_node].opr.ctx_type;
+	    }
+	  clone_dest = duplicate_node (dfa, org_dest, constraint);
+	  if (BE (clone_dest == -1, 0))
+	    return REG_ESPACE;
+	  ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
+	  if (BE (ret < 0, 0))
+	    return REG_ESPACE;
+	}
+      else /* dfa->edests[org_node].nelem == 2 */
+	{
+	  /* In case of the node can epsilon-transit, and it has two
+	     destinations. In the bin_tree_t and DFA, that's '|' and '*'.   */
+	  org_dest = dfa->edests[org_node].elems[0];
+	  re_node_set_empty (dfa->edests + clone_node);
+	  /* Search for a duplicated node which satisfies the constraint.  */
+	  clone_dest = search_duplicated_node (dfa, org_dest, constraint);
+	  if (clone_dest == -1)
+	    {
+	      /* There are no such a duplicated node, create a new one.  */
+	      reg_errcode_t err;
+	      clone_dest = duplicate_node (dfa, org_dest, constraint);
+	      if (BE (clone_dest == -1, 0))
+		return REG_ESPACE;
+	      ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
+	      if (BE (ret < 0, 0))
+		return REG_ESPACE;
+	      err = duplicate_node_closure (dfa, org_dest, clone_dest,
+					    root_node, constraint);
+	      if (BE (err != REG_NOERROR, 0))
+		return err;
+	    }
+	  else
+	    {
+	      /* There are a duplicated node which satisfy the constraint,
+		 use it to avoid infinite loop.  */
+	      ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
+	      if (BE (ret < 0, 0))
+		return REG_ESPACE;
+	    }
+
+	  org_dest = dfa->edests[org_node].elems[1];
+	  clone_dest = duplicate_node (dfa, org_dest, constraint);
+	  if (BE (clone_dest == -1, 0))
+	    return REG_ESPACE;
+	  ret = re_node_set_insert (dfa->edests + clone_node, clone_dest);
+	  if (BE (ret < 0, 0))
+	    return REG_ESPACE;
+	}
+      org_node = org_dest;
+      clone_node = clone_dest;
+    }
+  return REG_NOERROR;
+}
+
+/* Search for a node which is duplicated from the node ORG_NODE, and
+   satisfies the constraint CONSTRAINT.  */
+
+static int
+search_duplicated_node (const re_dfa_t *dfa, int org_node,
+			unsigned int constraint)
+{
+  int idx;
+  for (idx = dfa->nodes_len - 1; dfa->nodes[idx].duplicated && idx > 0; --idx)
+    {
+      if (org_node == dfa->org_indices[idx]
+	  && constraint == dfa->nodes[idx].constraint)
+	return idx; /* Found.  */
+    }
+  return -1; /* Not found.  */
+}
+
+/* Duplicate the node whose index is ORG_IDX and set the constraint CONSTRAINT.
+   Return the index of the new node, or -1 if insufficient storage is
+   available.  */
+
+static int
+duplicate_node (re_dfa_t *dfa, int org_idx, unsigned int constraint)
+{
+  int dup_idx = re_dfa_add_node (dfa, dfa->nodes[org_idx]);
+  if (BE (dup_idx != -1, 1))
+    {
+      dfa->nodes[dup_idx].constraint = constraint;
+      if (dfa->nodes[org_idx].type == ANCHOR)
+	dfa->nodes[dup_idx].constraint |= dfa->nodes[org_idx].opr.ctx_type;
+      dfa->nodes[dup_idx].duplicated = 1;
+
+      /* Store the index of the original node.  */
+      dfa->org_indices[dup_idx] = org_idx;
+    }
+  return dup_idx;
+}
+
+static reg_errcode_t
+calc_inveclosure (re_dfa_t *dfa)
+{
+  int src, idx, ret;
+  for (idx = 0; idx < dfa->nodes_len; ++idx)
+    re_node_set_init_empty (dfa->inveclosures + idx);
+
+  for (src = 0; src < dfa->nodes_len; ++src)
+    {
+      int *elems = dfa->eclosures[src].elems;
+      for (idx = 0; idx < dfa->eclosures[src].nelem; ++idx)
+	{
+	  ret = re_node_set_insert_last (dfa->inveclosures + elems[idx], src);
+	  if (BE (ret == -1, 0))
+	    return REG_ESPACE;
+	}
+    }
+
+  return REG_NOERROR;
+}
+
+/* Calculate "eclosure" for all the node in DFA.  */
+
+static reg_errcode_t
+calc_eclosure (re_dfa_t *dfa)
+{
+  int node_idx, incomplete;
+#ifdef DEBUG
+  assert (dfa->nodes_len > 0);
+#endif
+  incomplete = 0;
+  /* For each nodes, calculate epsilon closure.  */
+  for (node_idx = 0; ; ++node_idx)
+    {
+      reg_errcode_t err;
+      re_node_set eclosure_elem;
+      if (node_idx == dfa->nodes_len)
+	{
+	  if (!incomplete)
+	    break;
+	  incomplete = 0;
+	  node_idx = 0;
+	}
+
+#ifdef DEBUG
+      assert (dfa->eclosures[node_idx].nelem != -1);
+#endif
+
+      /* If we have already calculated, skip it.  */
+      if (dfa->eclosures[node_idx].nelem != 0)
+	continue;
+      /* Calculate epsilon closure of `node_idx'.  */
+      err = calc_eclosure_iter (&eclosure_elem, dfa, node_idx, 1);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+
+      if (dfa->eclosures[node_idx].nelem == 0)
+	{
+	  incomplete = 1;
+	  re_node_set_free (&eclosure_elem);
+	}
+    }
+  return REG_NOERROR;
+}
+
+/* Calculate epsilon closure of NODE.  */
+
+static reg_errcode_t
+calc_eclosure_iter (re_node_set *new_set, re_dfa_t *dfa, int node, int root)
+{
+  reg_errcode_t err;
+  unsigned int constraint;
+  int i, incomplete;
+  re_node_set eclosure;
+  incomplete = 0;
+  err = re_node_set_alloc (&eclosure, dfa->edests[node].nelem + 1);
+  if (BE (err != REG_NOERROR, 0))
+    return err;
+
+  /* This indicates that we are calculating this node now.
+     We reference this value to avoid infinite loop.  */
+  dfa->eclosures[node].nelem = -1;
+
+  constraint = ((dfa->nodes[node].type == ANCHOR)
+		? dfa->nodes[node].opr.ctx_type : 0);
+  /* If the current node has constraints, duplicate all nodes.
+     Since they must inherit the constraints.  */
+  if (constraint
+      && dfa->edests[node].nelem
+      && !dfa->nodes[dfa->edests[node].elems[0]].duplicated)
+    {
+      err = duplicate_node_closure (dfa, node, node, node, constraint);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+    }
+
+  /* Expand each epsilon destination nodes.  */
+  if (IS_EPSILON_NODE(dfa->nodes[node].type))
+    for (i = 0; i < dfa->edests[node].nelem; ++i)
+      {
+	re_node_set eclosure_elem;
+	int edest = dfa->edests[node].elems[i];
+	/* If calculating the epsilon closure of `edest' is in progress,
+	   return intermediate result.  */
+	if (dfa->eclosures[edest].nelem == -1)
+	  {
+	    incomplete = 1;
+	    continue;
+	  }
+	/* If we haven't calculated the epsilon closure of `edest' yet,
+	   calculate now. Otherwise use calculated epsilon closure.  */
+	if (dfa->eclosures[edest].nelem == 0)
+	  {
+	    err = calc_eclosure_iter (&eclosure_elem, dfa, edest, 0);
+	    if (BE (err != REG_NOERROR, 0))
+	      return err;
+	  }
+	else
+	  eclosure_elem = dfa->eclosures[edest];
+	/* Merge the epsilon closure of `edest'.  */
+	re_node_set_merge (&eclosure, &eclosure_elem);
+	/* If the epsilon closure of `edest' is incomplete,
+	   the epsilon closure of this node is also incomplete.  */
+	if (dfa->eclosures[edest].nelem == 0)
+	  {
+	    incomplete = 1;
+	    re_node_set_free (&eclosure_elem);
+	  }
+      }
+
+  /* Epsilon closures include itself.  */
+  re_node_set_insert (&eclosure, node);
+  if (incomplete && !root)
+    dfa->eclosures[node].nelem = 0;
+  else
+    dfa->eclosures[node] = eclosure;
+  *new_set = eclosure;
+  return REG_NOERROR;
+}
+
+/* Functions for token which are used in the parser.  */
+
+/* Fetch a token from INPUT.
+   We must not use this function inside bracket expressions.  */
+
+static void
+internal_function
+fetch_token (re_token_t *result, re_string_t *input, reg_syntax_t syntax)
+{
+  re_string_skip_bytes (input, peek_token (result, input, syntax));
+}
+
+/* Peek a token from INPUT, and return the length of the token.
+   We must not use this function inside bracket expressions.  */
+
+static int
+internal_function
+peek_token (re_token_t *token, re_string_t *input, reg_syntax_t syntax)
+{
+  unsigned char c;
+
+  if (re_string_eoi (input))
+    {
+      token->type = END_OF_RE;
+      return 0;
+    }
+
+  c = re_string_peek_byte (input, 0);
+  token->opr.c = c;
+
+  token->word_char = 0;
+#ifdef RE_ENABLE_I18N
+  token->mb_partial = 0;
+  if (input->mb_cur_max > 1 &&
+      !re_string_first_byte (input, re_string_cur_idx (input)))
+    {
+      token->type = CHARACTER;
+      token->mb_partial = 1;
+      return 1;
+    }
+#endif
+  if (c == '\\')
+    {
+      unsigned char c2;
+      if (re_string_cur_idx (input) + 1 >= re_string_length (input))
+	{
+	  token->type = BACK_SLASH;
+	  return 1;
+	}
+
+      c2 = re_string_peek_byte_case (input, 1);
+      token->opr.c = c2;
+      token->type = CHARACTER;
+#ifdef RE_ENABLE_I18N
+      if (input->mb_cur_max > 1)
+	{
+	  wint_t wc = re_string_wchar_at (input,
+					  re_string_cur_idx (input) + 1);
+	  token->word_char = IS_WIDE_WORD_CHAR (wc) != 0;
+	}
+      else
+#endif
+	token->word_char = IS_WORD_CHAR (c2) != 0;
+
+      switch (c2)
+	{
+	case '|':
+	  if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_NO_BK_VBAR))
+	    token->type = OP_ALT;
+	  break;
+	case '1': case '2': case '3': case '4': case '5':
+	case '6': case '7': case '8': case '9':
+	  if (!(syntax & RE_NO_BK_REFS))
+	    {
+	      token->type = OP_BACK_REF;
+	      token->opr.idx = c2 - '1';
+	    }
+	  break;
+	case '<':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    {
+	      token->type = ANCHOR;
+	      token->opr.ctx_type = WORD_FIRST;
+	    }
+	  break;
+	case '>':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    {
+	      token->type = ANCHOR;
+	      token->opr.ctx_type = WORD_LAST;
+	    }
+	  break;
+	case 'b':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    {
+	      token->type = ANCHOR;
+	      token->opr.ctx_type = WORD_DELIM;
+	    }
+	  break;
+	case 'B':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    {
+	      token->type = ANCHOR;
+	      token->opr.ctx_type = NOT_WORD_DELIM;
+	    }
+	  break;
+	case 'w':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    token->type = OP_WORD;
+	  break;
+	case 'W':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    token->type = OP_NOTWORD;
+	  break;
+	case 's':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    token->type = OP_SPACE;
+	  break;
+	case 'S':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    token->type = OP_NOTSPACE;
+	  break;
+	case '`':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    {
+	      token->type = ANCHOR;
+	      token->opr.ctx_type = BUF_FIRST;
+	    }
+	  break;
+	case '\'':
+	  if (!(syntax & RE_NO_GNU_OPS))
+	    {
+	      token->type = ANCHOR;
+	      token->opr.ctx_type = BUF_LAST;
+	    }
+	  break;
+	case '(':
+	  if (!(syntax & RE_NO_BK_PARENS))
+	    token->type = OP_OPEN_SUBEXP;
+	  break;
+	case ')':
+	  if (!(syntax & RE_NO_BK_PARENS))
+	    token->type = OP_CLOSE_SUBEXP;
+	  break;
+	case '+':
+	  if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_BK_PLUS_QM))
+	    token->type = OP_DUP_PLUS;
+	  break;
+	case '?':
+	  if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_BK_PLUS_QM))
+	    token->type = OP_DUP_QUESTION;
+	  break;
+	case '{':
+	  if ((syntax & RE_INTERVALS) && (!(syntax & RE_NO_BK_BRACES)))
+	    token->type = OP_OPEN_DUP_NUM;
+	  break;
+	case '}':
+	  if ((syntax & RE_INTERVALS) && (!(syntax & RE_NO_BK_BRACES)))
+	    token->type = OP_CLOSE_DUP_NUM;
+	  break;
+	default:
+	  break;
+	}
+      return 2;
+    }
+
+  token->type = CHARACTER;
+#ifdef RE_ENABLE_I18N
+  if (input->mb_cur_max > 1)
+    {
+      wint_t wc = re_string_wchar_at (input, re_string_cur_idx (input));
+      token->word_char = IS_WIDE_WORD_CHAR (wc) != 0;
+    }
+  else
+#endif
+    token->word_char = IS_WORD_CHAR (token->opr.c);
+
+  switch (c)
+    {
+    case '\n':
+      if (syntax & RE_NEWLINE_ALT)
+	token->type = OP_ALT;
+      break;
+    case '|':
+      if (!(syntax & RE_LIMITED_OPS) && (syntax & RE_NO_BK_VBAR))
+	token->type = OP_ALT;
+      break;
+    case '*':
+      token->type = OP_DUP_ASTERISK;
+      break;
+    case '+':
+      if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_BK_PLUS_QM))
+	token->type = OP_DUP_PLUS;
+      break;
+    case '?':
+      if (!(syntax & RE_LIMITED_OPS) && !(syntax & RE_BK_PLUS_QM))
+	token->type = OP_DUP_QUESTION;
+      break;
+    case '{':
+      if ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
+	token->type = OP_OPEN_DUP_NUM;
+      break;
+    case '}':
+      if ((syntax & RE_INTERVALS) && (syntax & RE_NO_BK_BRACES))
+	token->type = OP_CLOSE_DUP_NUM;
+      break;
+    case '(':
+      if (syntax & RE_NO_BK_PARENS)
+	token->type = OP_OPEN_SUBEXP;
+      break;
+    case ')':
+      if (syntax & RE_NO_BK_PARENS)
+	token->type = OP_CLOSE_SUBEXP;
+      break;
+    case '[':
+      token->type = OP_OPEN_BRACKET;
+      break;
+    case '.':
+      token->type = OP_PERIOD;
+      break;
+    case '^':
+      if (!(syntax & (RE_CONTEXT_INDEP_ANCHORS | RE_CARET_ANCHORS_HERE)) &&
+	  re_string_cur_idx (input) != 0)
+	{
+	  char prev = re_string_peek_byte (input, -1);
+	  if (!(syntax & RE_NEWLINE_ALT) || prev != '\n')
+	    break;
+	}
+      token->type = ANCHOR;
+      token->opr.ctx_type = LINE_FIRST;
+      break;
+    case '$':
+      if (!(syntax & RE_CONTEXT_INDEP_ANCHORS) &&
+	  re_string_cur_idx (input) + 1 != re_string_length (input))
+	{
+	  re_token_t next;
+	  re_string_skip_bytes (input, 1);
+	  peek_token (&next, input, syntax);
+	  re_string_skip_bytes (input, -1);
+	  if (next.type != OP_ALT && next.type != OP_CLOSE_SUBEXP)
+	    break;
+	}
+      token->type = ANCHOR;
+      token->opr.ctx_type = LINE_LAST;
+      break;
+    default:
+      break;
+    }
+  return 1;
+}
+
+/* Peek a token from INPUT, and return the length of the token.
+   We must not use this function out of bracket expressions.  */
+
+static int
+internal_function
+peek_token_bracket (re_token_t *token, re_string_t *input, reg_syntax_t syntax)
+{
+  unsigned char c;
+  if (re_string_eoi (input))
+    {
+      token->type = END_OF_RE;
+      return 0;
+    }
+  c = re_string_peek_byte (input, 0);
+  token->opr.c = c;
+
+#ifdef RE_ENABLE_I18N
+  if (input->mb_cur_max > 1 &&
+      !re_string_first_byte (input, re_string_cur_idx (input)))
+    {
+      token->type = CHARACTER;
+      return 1;
+    }
+#endif /* RE_ENABLE_I18N */
+
+  if (c == '\\' && (syntax & RE_BACKSLASH_ESCAPE_IN_LISTS)
+      && re_string_cur_idx (input) + 1 < re_string_length (input))
+    {
+      /* In this case, '\' escape a character.  */
+      unsigned char c2;
+      re_string_skip_bytes (input, 1);
+      c2 = re_string_peek_byte (input, 0);
+      token->opr.c = c2;
+      token->type = CHARACTER;
+      return 1;
+    }
+  if (c == '[') /* '[' is a special char in a bracket exps.  */
+    {
+      unsigned char c2;
+      int token_len;
+      if (re_string_cur_idx (input) + 1 < re_string_length (input))
+	c2 = re_string_peek_byte (input, 1);
+      else
+	c2 = 0;
+      token->opr.c = c2;
+      token_len = 2;
+      switch (c2)
+	{
+	case '.':
+	  token->type = OP_OPEN_COLL_ELEM;
+	  break;
+	case '=':
+	  token->type = OP_OPEN_EQUIV_CLASS;
+	  break;
+	case ':':
+	  if (syntax & RE_CHAR_CLASSES)
+	    {
+	      token->type = OP_OPEN_CHAR_CLASS;
+	      break;
+	    }
+	  /* else fall through.  */
+	default:
+	  token->type = CHARACTER;
+	  token->opr.c = c;
+	  token_len = 1;
+	  break;
+	}
+      return token_len;
+    }
+  switch (c)
+    {
+    case '-':
+      token->type = OP_CHARSET_RANGE;
+      break;
+    case ']':
+      token->type = OP_CLOSE_BRACKET;
+      break;
+    case '^':
+      token->type = OP_NON_MATCH_LIST;
+      break;
+    default:
+      token->type = CHARACTER;
+    }
+  return 1;
+}
+
+/* Functions for parser.  */
+
+/* Entry point of the parser.
+   Parse the regular expression REGEXP and return the structure tree.
+   If an error is occured, ERR is set by error code, and return NULL.
+   This function build the following tree, from regular expression <reg_exp>:
+	   CAT
+	   / \
+	  /   \
+   <reg_exp>  EOR
+
+   CAT means concatenation.
+   EOR means end of regular expression.  */
+
+static bin_tree_t *
+parse (re_string_t *regexp, regex_t *preg, reg_syntax_t syntax,
+       reg_errcode_t *err)
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  bin_tree_t *tree, *eor, *root;
+  re_token_t current_token;
+  dfa->syntax = syntax;
+  fetch_token (&current_token, regexp, syntax | RE_CARET_ANCHORS_HERE);
+  tree = parse_reg_exp (regexp, preg, &current_token, syntax, 0, err);
+  if (BE (*err != REG_NOERROR && tree == NULL, 0))
+    return NULL;
+  eor = create_tree (dfa, NULL, NULL, END_OF_RE);
+  if (tree != NULL)
+    root = create_tree (dfa, tree, eor, CONCAT);
+  else
+    root = eor;
+  if (BE (eor == NULL || root == NULL, 0))
+    {
+      *err = REG_ESPACE;
+      return NULL;
+    }
+  return root;
+}
+
+/* This function build the following tree, from regular expression
+   <branch1>|<branch2>:
+	   ALT
+	   / \
+	  /   \
+   <branch1> <branch2>
+
+   ALT means alternative, which represents the operator `|'.  */
+
+static bin_tree_t *
+parse_reg_exp (re_string_t *regexp, regex_t *preg, re_token_t *token,
+	       reg_syntax_t syntax, int nest, reg_errcode_t *err)
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  bin_tree_t *tree, *branch = NULL;
+  tree = parse_branch (regexp, preg, token, syntax, nest, err);
+  if (BE (*err != REG_NOERROR && tree == NULL, 0))
+    return NULL;
+
+  while (token->type == OP_ALT)
+    {
+      fetch_token (token, regexp, syntax | RE_CARET_ANCHORS_HERE);
+      if (token->type != OP_ALT && token->type != END_OF_RE
+	  && (nest == 0 || token->type != OP_CLOSE_SUBEXP))
+	{
+	  branch = parse_branch (regexp, preg, token, syntax, nest, err);
+	  if (BE (*err != REG_NOERROR && branch == NULL, 0))
+	    return NULL;
+	}
+      else
+	branch = NULL;
+      tree = create_tree (dfa, tree, branch, OP_ALT);
+      if (BE (tree == NULL, 0))
+	{
+	  *err = REG_ESPACE;
+	  return NULL;
+	}
+    }
+  return tree;
+}
+
+/* This function build the following tree, from regular expression
+   <exp1><exp2>:
+	CAT
+	/ \
+       /   \
+   <exp1> <exp2>
+
+   CAT means concatenation.  */
+
+static bin_tree_t *
+parse_branch (re_string_t *regexp, regex_t *preg, re_token_t *token,
+	      reg_syntax_t syntax, int nest, reg_errcode_t *err)
+{
+  bin_tree_t *tree, *exp;
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  tree = parse_expression (regexp, preg, token, syntax, nest, err);
+  if (BE (*err != REG_NOERROR && tree == NULL, 0))
+    return NULL;
+
+  while (token->type != OP_ALT && token->type != END_OF_RE
+	 && (nest == 0 || token->type != OP_CLOSE_SUBEXP))
+    {
+      exp = parse_expression (regexp, preg, token, syntax, nest, err);
+      if (BE (*err != REG_NOERROR && exp == NULL, 0))
+	{
+	  return NULL;
+	}
+      if (tree != NULL && exp != NULL)
+	{
+	  tree = create_tree (dfa, tree, exp, CONCAT);
+	  if (tree == NULL)
+	    {
+	      *err = REG_ESPACE;
+	      return NULL;
+	    }
+	}
+      else if (tree == NULL)
+	tree = exp;
+      /* Otherwise exp == NULL, we don't need to create new tree.  */
+    }
+  return tree;
+}
+
+/* This function build the following tree, from regular expression a*:
+	 *
+	 |
+	 a
+*/
+
+static bin_tree_t *
+parse_expression (re_string_t *regexp, regex_t *preg, re_token_t *token,
+		  reg_syntax_t syntax, int nest, reg_errcode_t *err)
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  bin_tree_t *tree;
+  switch (token->type)
+    {
+    case CHARACTER:
+      tree = create_token_tree (dfa, NULL, NULL, token);
+      if (BE (tree == NULL, 0))
+	{
+	  *err = REG_ESPACE;
+	  return NULL;
+	}
+#ifdef RE_ENABLE_I18N
+      if (dfa->mb_cur_max > 1)
+	{
+	  while (!re_string_eoi (regexp)
+		 && !re_string_first_byte (regexp, re_string_cur_idx (regexp)))
+	    {
+	      bin_tree_t *mbc_remain;
+	      fetch_token (token, regexp, syntax);
+	      mbc_remain = create_token_tree (dfa, NULL, NULL, token);
+	      tree = create_tree (dfa, tree, mbc_remain, CONCAT);
+	      if (BE (mbc_remain == NULL || tree == NULL, 0))
+		{
+		  *err = REG_ESPACE;
+		  return NULL;
+		}
+	    }
+	}
+#endif
+      break;
+    case OP_OPEN_SUBEXP:
+      tree = parse_sub_exp (regexp, preg, token, syntax, nest + 1, err);
+      if (BE (*err != REG_NOERROR && tree == NULL, 0))
+	return NULL;
+      break;
+    case OP_OPEN_BRACKET:
+      tree = parse_bracket_exp (regexp, dfa, token, syntax, err);
+      if (BE (*err != REG_NOERROR && tree == NULL, 0))
+	return NULL;
+      break;
+    case OP_BACK_REF:
+      if (!BE (dfa->completed_bkref_map & (1 << token->opr.idx), 1))
+	{
+	  *err = REG_ESUBREG;
+	  return NULL;
+	}
+      dfa->used_bkref_map |= 1 << token->opr.idx;
+      tree = create_token_tree (dfa, NULL, NULL, token);
+      if (BE (tree == NULL, 0))
+	{
+	  *err = REG_ESPACE;
+	  return NULL;
+	}
+      ++dfa->nbackref;
+      dfa->has_mb_node = 1;
+      break;
+    case OP_OPEN_DUP_NUM:
+      if (syntax & RE_CONTEXT_INVALID_DUP)
+	{
+	  *err = REG_BADRPT;
+	  return NULL;
+	}
+      /* FALLTHROUGH */
+    case OP_DUP_ASTERISK:
+    case OP_DUP_PLUS:
+    case OP_DUP_QUESTION:
+      if (syntax & RE_CONTEXT_INVALID_OPS)
+	{
+	  *err = REG_BADRPT;
+	  return NULL;
+	}
+      else if (syntax & RE_CONTEXT_INDEP_OPS)
+	{
+	  fetch_token (token, regexp, syntax);
+	  return parse_expression (regexp, preg, token, syntax, nest, err);
+	}
+      /* else fall through  */
+    case OP_CLOSE_SUBEXP:
+      if ((token->type == OP_CLOSE_SUBEXP) &&
+	  !(syntax & RE_UNMATCHED_RIGHT_PAREN_ORD))
+	{
+	  *err = REG_ERPAREN;
+	  return NULL;
+	}
+      /* else fall through  */
+    case OP_CLOSE_DUP_NUM:
+      /* We treat it as a normal character.  */
+
+      /* Then we can these characters as normal characters.  */
+      token->type = CHARACTER;
+      /* mb_partial and word_char bits should be initialized already
+	 by peek_token.  */
+      tree = create_token_tree (dfa, NULL, NULL, token);
+      if (BE (tree == NULL, 0))
+	{
+	  *err = REG_ESPACE;
+	  return NULL;
+	}
+      break;
+    case ANCHOR:
+      if ((token->opr.ctx_type
+	   & (WORD_DELIM | NOT_WORD_DELIM | WORD_FIRST | WORD_LAST))
+	  && dfa->word_ops_used == 0)
+	init_word_char (dfa);
+      if (token->opr.ctx_type == WORD_DELIM
+          || token->opr.ctx_type == NOT_WORD_DELIM)
+	{
+	  bin_tree_t *tree_first, *tree_last;
+	  if (token->opr.ctx_type == WORD_DELIM)
+	    {
+	      token->opr.ctx_type = WORD_FIRST;
+	      tree_first = create_token_tree (dfa, NULL, NULL, token);
+	      token->opr.ctx_type = WORD_LAST;
+            }
+          else
+            {
+	      token->opr.ctx_type = INSIDE_WORD;
+	      tree_first = create_token_tree (dfa, NULL, NULL, token);
+	      token->opr.ctx_type = INSIDE_NOTWORD;
+            }
+	  tree_last = create_token_tree (dfa, NULL, NULL, token);
+	  tree = create_tree (dfa, tree_first, tree_last, OP_ALT);
+	  if (BE (tree_first == NULL || tree_last == NULL || tree == NULL, 0))
+	    {
+	      *err = REG_ESPACE;
+	      return NULL;
+	    }
+	}
+      else
+	{
+	  tree = create_token_tree (dfa, NULL, NULL, token);
+	  if (BE (tree == NULL, 0))
+	    {
+	      *err = REG_ESPACE;
+	      return NULL;
+	    }
+	}
+      /* We must return here, since ANCHORs can't be followed
+	 by repetition operators.
+	 eg. RE"^*" is invalid or "<ANCHOR(^)><CHAR(*)>",
+	     it must not be "<ANCHOR(^)><REPEAT(*)>".  */
+      fetch_token (token, regexp, syntax);
+      return tree;
+    case OP_PERIOD:
+      tree = create_token_tree (dfa, NULL, NULL, token);
+      if (BE (tree == NULL, 0))
+	{
+	  *err = REG_ESPACE;
+	  return NULL;
+	}
+      if (dfa->mb_cur_max > 1)
+	dfa->has_mb_node = 1;
+      break;
+    case OP_WORD:
+    case OP_NOTWORD:
+      tree = build_charclass_op (dfa, regexp->trans,
+				 (const unsigned char *) "alnum",
+				 (const unsigned char *) "_",
+				 token->type == OP_NOTWORD, err);
+      if (BE (*err != REG_NOERROR && tree == NULL, 0))
+	return NULL;
+      break;
+    case OP_SPACE:
+    case OP_NOTSPACE:
+      tree = build_charclass_op (dfa, regexp->trans,
+				 (const unsigned char *) "space",
+				 (const unsigned char *) "",
+				 token->type == OP_NOTSPACE, err);
+      if (BE (*err != REG_NOERROR && tree == NULL, 0))
+	return NULL;
+      break;
+    case OP_ALT:
+    case END_OF_RE:
+      return NULL;
+    case BACK_SLASH:
+      *err = REG_EESCAPE;
+      return NULL;
+    default:
+      /* Must not happen?  */
+#ifdef DEBUG
+      assert (0);
+#endif
+      return NULL;
+    }
+  fetch_token (token, regexp, syntax);
+
+  while (token->type == OP_DUP_ASTERISK || token->type == OP_DUP_PLUS
+	 || token->type == OP_DUP_QUESTION || token->type == OP_OPEN_DUP_NUM)
+    {
+      tree = parse_dup_op (tree, regexp, dfa, token, syntax, err);
+      if (BE (*err != REG_NOERROR && tree == NULL, 0))
+	return NULL;
+      /* In BRE consecutive duplications are not allowed.  */
+      if ((syntax & RE_CONTEXT_INVALID_DUP)
+	  && (token->type == OP_DUP_ASTERISK
+	      || token->type == OP_OPEN_DUP_NUM))
+	{
+	  *err = REG_BADRPT;
+	  return NULL;
+	}
+    }
+
+  return tree;
+}
+
+/* This function build the following tree, from regular expression
+   (<reg_exp>):
+	 SUBEXP
+	    |
+	<reg_exp>
+*/
+
+static bin_tree_t *
+parse_sub_exp (re_string_t *regexp, regex_t *preg, re_token_t *token,
+	       reg_syntax_t syntax, int nest, reg_errcode_t *err)
+{
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+  bin_tree_t *tree;
+  size_t cur_nsub;
+  cur_nsub = preg->re_nsub++;
+
+  fetch_token (token, regexp, syntax | RE_CARET_ANCHORS_HERE);
+
+  /* The subexpression may be a null string.  */
+  if (token->type == OP_CLOSE_SUBEXP)
+    tree = NULL;
+  else
+    {
+      tree = parse_reg_exp (regexp, preg, token, syntax, nest, err);
+      if (BE (*err == REG_NOERROR && token->type != OP_CLOSE_SUBEXP, 0))
+        *err = REG_EPAREN;
+      if (BE (*err != REG_NOERROR, 0))
+	return NULL;
+    }
+
+  if (cur_nsub <= '9' - '1')
+    dfa->completed_bkref_map |= 1 << cur_nsub;
+
+  tree = create_tree (dfa, tree, NULL, SUBEXP);
+  if (BE (tree == NULL, 0))
+    {
+      *err = REG_ESPACE;
+      return NULL;
+    }
+  tree->token.opr.idx = cur_nsub;
+  return tree;
+}
+
+/* This function parse repetition operators like "*", "+", "{1,3}" etc.  */
+
+static bin_tree_t *
+parse_dup_op (bin_tree_t *elem, re_string_t *regexp, re_dfa_t *dfa,
+	      re_token_t *token, reg_syntax_t syntax, reg_errcode_t *err)
+{
+  bin_tree_t *tree = NULL, *old_tree = NULL;
+  int i, start, end, start_idx = re_string_cur_idx (regexp);
+  re_token_t start_token = *token;
+
+  if (token->type == OP_OPEN_DUP_NUM)
+    {
+      end = 0;
+      start = fetch_number (regexp, token, syntax);
+      if (start == -1)
+	{
+	  if (token->type == CHARACTER && token->opr.c == ',')
+	    start = 0; /* We treat "{,m}" as "{0,m}".  */
+	  else
+	    {
+	      *err = REG_BADBR; /* <re>{} is invalid.  */
+	      return NULL;
+	    }
+	}
+      if (BE (start != -2, 1))
+	{
+	  /* We treat "{n}" as "{n,n}".  */
+	  end = ((token->type == OP_CLOSE_DUP_NUM) ? start
+		 : ((token->type == CHARACTER && token->opr.c == ',')
+		    ? fetch_number (regexp, token, syntax) : -2));
+	}
+      if (BE (start == -2 || end == -2, 0))
+	{
+	  /* Invalid sequence.  */
+	  if (BE (!(syntax & RE_INVALID_INTERVAL_ORD), 0))
+	    {
+	      if (token->type == END_OF_RE)
+		*err = REG_EBRACE;
+	      else
+		*err = REG_BADBR;
+
+	      return NULL;
+	    }
+
+	  /* If the syntax bit is set, rollback.  */
+	  re_string_set_index (regexp, start_idx);
+	  *token = start_token;
+	  token->type = CHARACTER;
+	  /* mb_partial and word_char bits should be already initialized by
+	     peek_token.  */
+	  return elem;
+	}
+
+      if (BE (end != -1 && start > end, 0))
+	{
+	  /* First number greater than second.  */
+	  *err = REG_BADBR;
+	  return NULL;
+	}
+    }
+  else
+    {
+      start = (token->type == OP_DUP_PLUS) ? 1 : 0;
+      end = (token->type == OP_DUP_QUESTION) ? 1 : -1;
+    }
+
+  fetch_token (token, regexp, syntax);
+
+  if (BE (elem == NULL, 0))
+    return NULL;
+  if (BE (start == 0 && end == 0, 0))
+    {
+      postorder (elem, free_tree, NULL);
+      return NULL;
+    }
+
+  /* Extract "<re>{n,m}" to "<re><re>...<re><re>{0,<m-n>}".  */
+  if (BE (start > 0, 0))
+    {
+      tree = elem;
+      for (i = 2; i <= start; ++i)
+	{
+	  elem = duplicate_tree (elem, dfa);
+	  tree = create_tree (dfa, tree, elem, CONCAT);
+	  if (BE (elem == NULL || tree == NULL, 0))
+	    goto parse_dup_op_espace;
+	}
+
+      if (start == end)
+	return tree;
+
+      /* Duplicate ELEM before it is marked optional.  */
+      elem = duplicate_tree (elem, dfa);
+      old_tree = tree;
+    }
+  else
+    old_tree = NULL;
+
+  if (elem->token.type == SUBEXP)
+    postorder (elem, mark_opt_subexp, (void *) (long) elem->token.opr.idx);
+
+  tree = create_tree (dfa, elem, NULL, (end == -1 ? OP_DUP_ASTERISK : OP_ALT));
+  if (BE (tree == NULL, 0))
+    goto parse_dup_op_espace;
+
+  /* This loop is actually executed only when end != -1,
+     to rewrite <re>{0,n} as (<re>(<re>...<re>?)?)?...  We have
+     already created the start+1-th copy.  */
+  for (i = start + 2; i <= end; ++i)
+    {
+      elem = duplicate_tree (elem, dfa);
+      tree = create_tree (dfa, tree, elem, CONCAT);
+      if (BE (elem == NULL || tree == NULL, 0))
+        goto parse_dup_op_espace;
+
+      tree = create_tree (dfa, tree, NULL, OP_ALT);
+      if (BE (tree == NULL, 0))
+        goto parse_dup_op_espace;
+    }
+
+  if (old_tree)
+    tree = create_tree (dfa, old_tree, tree, CONCAT);
+
+  return tree;
+
+ parse_dup_op_espace:
+  *err = REG_ESPACE;
+  return NULL;
+}
+
+/* Size of the names for collating symbol/equivalence_class/character_class.
+   I'm not sure, but maybe enough.  */
+#define BRACKET_NAME_BUF_SIZE 32
+
+#ifndef _LIBC
+  /* Local function for parse_bracket_exp only used in case of NOT _LIBC.
+     Build the range expression which starts from START_ELEM, and ends
+     at END_ELEM.  The result are written to MBCSET and SBCSET.
+     RANGE_ALLOC is the allocated size of mbcset->range_starts, and
+     mbcset->range_ends, is a pointer argument sinse we may
+     update it.  */
+
+static reg_errcode_t
+internal_function
+# ifdef RE_ENABLE_I18N
+build_range_exp (bitset_t sbcset, re_charset_t *mbcset, int *range_alloc,
+		 bracket_elem_t *start_elem, bracket_elem_t *end_elem)
+# else /* not RE_ENABLE_I18N */
+build_range_exp (bitset_t sbcset, bracket_elem_t *start_elem,
+		 bracket_elem_t *end_elem)
+# endif /* not RE_ENABLE_I18N */
+{
+  unsigned int start_ch, end_ch;
+  /* Equivalence Classes and Character Classes can't be a range start/end.  */
+  if (BE (start_elem->type == EQUIV_CLASS || start_elem->type == CHAR_CLASS
+	  || end_elem->type == EQUIV_CLASS || end_elem->type == CHAR_CLASS,
+	  0))
+    return REG_ERANGE;
+
+  /* We can handle no multi character collating elements without libc
+     support.  */
+  if (BE ((start_elem->type == COLL_SYM
+	   && strlen ((char *) start_elem->opr.name) > 1)
+	  || (end_elem->type == COLL_SYM
+	      && strlen ((char *) end_elem->opr.name) > 1), 0))
+    return REG_ECOLLATE;
+
+# ifdef RE_ENABLE_I18N
+  {
+    wchar_t wc;
+    wint_t start_wc;
+    wint_t end_wc;
+    wchar_t cmp_buf[6] = {L'\0', L'\0', L'\0', L'\0', L'\0', L'\0'};
+
+    start_ch = ((start_elem->type == SB_CHAR) ? start_elem->opr.ch
+		: ((start_elem->type == COLL_SYM) ? start_elem->opr.name[0]
+		   : 0));
+    end_ch = ((end_elem->type == SB_CHAR) ? end_elem->opr.ch
+	      : ((end_elem->type == COLL_SYM) ? end_elem->opr.name[0]
+		 : 0));
+    start_wc = ((start_elem->type == SB_CHAR || start_elem->type == COLL_SYM)
+		? __btowc (start_ch) : start_elem->opr.wch);
+    end_wc = ((end_elem->type == SB_CHAR || end_elem->type == COLL_SYM)
+	      ? __btowc (end_ch) : end_elem->opr.wch);
+    if (start_wc == WEOF || end_wc == WEOF)
+      return REG_ECOLLATE;
+    cmp_buf[0] = start_wc;
+    cmp_buf[4] = end_wc;
+    if (wcscoll (cmp_buf, cmp_buf + 4) > 0)
+      return REG_ERANGE;
+
+    /* Got valid collation sequence values, add them as a new entry.
+       However, for !_LIBC we have no collation elements: if the
+       character set is single byte, the single byte character set
+       that we build below suffices.  parse_bracket_exp passes
+       no MBCSET if dfa->mb_cur_max == 1.  */
+    if (mbcset)
+      {
+        /* Check the space of the arrays.  */
+        if (BE (*range_alloc == mbcset->nranges, 0))
+          {
+	    /* There is not enough space, need realloc.  */
+	    wchar_t *new_array_start, *new_array_end;
+	    int new_nranges;
+
+	    /* +1 in case of mbcset->nranges is 0.  */
+	    new_nranges = 2 * mbcset->nranges + 1;
+	    /* Use realloc since mbcset->range_starts and mbcset->range_ends
+	       are NULL if *range_alloc == 0.  */
+	    new_array_start = re_realloc (mbcset->range_starts, wchar_t,
+				          new_nranges);
+	    new_array_end = re_realloc (mbcset->range_ends, wchar_t,
+				        new_nranges);
+
+	    if (BE (new_array_start == NULL || new_array_end == NULL, 0))
+	      return REG_ESPACE;
+
+	    mbcset->range_starts = new_array_start;
+	    mbcset->range_ends = new_array_end;
+	    *range_alloc = new_nranges;
+          }
+
+        mbcset->range_starts[mbcset->nranges] = start_wc;
+        mbcset->range_ends[mbcset->nranges++] = end_wc;
+      }
+
+    /* Build the table for single byte characters.  */
+    for (wc = 0; wc < SBC_MAX; ++wc)
+      {
+	cmp_buf[2] = wc;
+	if (wcscoll (cmp_buf, cmp_buf + 2) <= 0
+	    && wcscoll (cmp_buf + 2, cmp_buf + 4) <= 0)
+	  bitset_set (sbcset, wc);
+      }
+  }
+# else /* not RE_ENABLE_I18N */
+  {
+    unsigned int ch;
+    start_ch = ((start_elem->type == SB_CHAR ) ? start_elem->opr.ch
+		: ((start_elem->type == COLL_SYM) ? start_elem->opr.name[0]
+		   : 0));
+    end_ch = ((end_elem->type == SB_CHAR ) ? end_elem->opr.ch
+	      : ((end_elem->type == COLL_SYM) ? end_elem->opr.name[0]
+		 : 0));
+    if (start_ch > end_ch)
+      return REG_ERANGE;
+    /* Build the table for single byte characters.  */
+    for (ch = 0; ch < SBC_MAX; ++ch)
+      if (start_ch <= ch  && ch <= end_ch)
+	bitset_set (sbcset, ch);
+  }
+# endif /* not RE_ENABLE_I18N */
+  return REG_NOERROR;
+}
+#endif /* not _LIBC */
+
+#ifndef _LIBC
+/* Helper function for parse_bracket_exp only used in case of NOT _LIBC..
+   Build the collating element which is represented by NAME.
+   The result are written to MBCSET and SBCSET.
+   COLL_SYM_ALLOC is the allocated size of mbcset->coll_sym, is a
+   pointer argument since we may update it.  */
+
+static reg_errcode_t
+internal_function
+# ifdef RE_ENABLE_I18N
+build_collating_symbol (bitset_t sbcset, re_charset_t *mbcset,
+			int *coll_sym_alloc, const unsigned char *name)
+# else /* not RE_ENABLE_I18N */
+build_collating_symbol (bitset_t sbcset, const unsigned char *name)
+# endif /* not RE_ENABLE_I18N */
+{
+  size_t name_len = strlen ((const char *) name);
+  if (BE (name_len != 1, 0))
+    return REG_ECOLLATE;
+  else
+    {
+      bitset_set (sbcset, name[0]);
+      return REG_NOERROR;
+    }
+}
+#endif /* not _LIBC */
+
+/* This function parse bracket expression like "[abc]", "[a-c]",
+   "[[.a-a.]]" etc.  */
+
+static bin_tree_t *
+parse_bracket_exp (re_string_t *regexp, re_dfa_t *dfa, re_token_t *token,
+		   reg_syntax_t syntax, reg_errcode_t *err)
+{
+#ifdef _LIBC
+  const unsigned char *collseqmb;
+  const char *collseqwc;
+  uint32_t nrules;
+  int32_t table_size;
+  const int32_t *symb_table;
+  const unsigned char *extra;
+
+  /* Local function for parse_bracket_exp used in _LIBC environement.
+     Seek the collating symbol entry correspondings to NAME.
+     Return the index of the symbol in the SYMB_TABLE.  */
+
+  auto inline int32_t
+  __attribute ((always_inline))
+  seek_collating_symbol_entry (name, name_len)
+	 const unsigned char *name;
+	 size_t name_len;
+    {
+      int32_t hash = elem_hash ((const char *) name, name_len);
+      int32_t elem = hash % table_size;
+      if (symb_table[2 * elem] != 0)
+	{
+	  int32_t second = hash % (table_size - 2) + 1;
+
+	  do
+	    {
+	      /* First compare the hashing value.  */
+	      if (symb_table[2 * elem] == hash
+		  /* Compare the length of the name.  */
+		  && name_len == extra[symb_table[2 * elem + 1]]
+		  /* Compare the name.  */
+		  && memcmp (name, &extra[symb_table[2 * elem + 1] + 1],
+			     name_len) == 0)
+		{
+		  /* Yep, this is the entry.  */
+		  break;
+		}
+
+	      /* Next entry.  */
+	      elem += second;
+	    }
+	  while (symb_table[2 * elem] != 0);
+	}
+      return elem;
+    }
+
+  /* Local function for parse_bracket_exp used in _LIBC environement.
+     Look up the collation sequence value of BR_ELEM.
+     Return the value if succeeded, UINT_MAX otherwise.  */
+
+  auto inline unsigned int
+  __attribute ((always_inline))
+  lookup_collation_sequence_value (br_elem)
+	 bracket_elem_t *br_elem;
+    {
+      if (br_elem->type == SB_CHAR)
+	{
+	  /*
+	  if (MB_CUR_MAX == 1)
+	  */
+	  if (nrules == 0)
+	    return collseqmb[br_elem->opr.ch];
+	  else
+	    {
+	      wint_t wc = __btowc (br_elem->opr.ch);
+	      return __collseq_table_lookup (collseqwc, wc);
+	    }
+	}
+      else if (br_elem->type == MB_CHAR)
+	{
+	  return __collseq_table_lookup (collseqwc, br_elem->opr.wch);
+	}
+      else if (br_elem->type == COLL_SYM)
+	{
+	  size_t sym_name_len = strlen ((char *) br_elem->opr.name);
+	  if (nrules != 0)
+	    {
+	      int32_t elem, idx;
+	      elem = seek_collating_symbol_entry (br_elem->opr.name,
+						  sym_name_len);
+	      if (symb_table[2 * elem] != 0)
+		{
+		  /* We found the entry.  */
+		  idx = symb_table[2 * elem + 1];
+		  /* Skip the name of collating element name.  */
+		  idx += 1 + extra[idx];
+		  /* Skip the byte sequence of the collating element.  */
+		  idx += 1 + extra[idx];
+		  /* Adjust for the alignment.  */
+		  idx = (idx + 3) & ~3;
+		  /* Skip the multibyte collation sequence value.  */
+		  idx += sizeof (unsigned int);
+		  /* Skip the wide char sequence of the collating element.  */
+		  idx += sizeof (unsigned int) *
+		    (1 + *(unsigned int *) (extra + idx));
+		  /* Return the collation sequence value.  */
+		  return *(unsigned int *) (extra + idx);
+		}
+	      else if (symb_table[2 * elem] == 0 && sym_name_len == 1)
+		{
+		  /* No valid character.  Match it as a single byte
+		     character.  */
+		  return collseqmb[br_elem->opr.name[0]];
+		}
+	    }
+	  else if (sym_name_len == 1)
+	    return collseqmb[br_elem->opr.name[0]];
+	}
+      return UINT_MAX;
+    }
+
+  /* Local function for parse_bracket_exp used in _LIBC environement.
+     Build the range expression which starts from START_ELEM, and ends
+     at END_ELEM.  The result are written to MBCSET and SBCSET.
+     RANGE_ALLOC is the allocated size of mbcset->range_starts, and
+     mbcset->range_ends, is a pointer argument sinse we may
+     update it.  */
+
+  auto inline reg_errcode_t
+  __attribute ((always_inline))
+  build_range_exp (sbcset, mbcset, range_alloc, start_elem, end_elem)
+	 re_charset_t *mbcset;
+	 int *range_alloc;
+	 bitset_t sbcset;
+	 bracket_elem_t *start_elem, *end_elem;
+    {
+      unsigned int ch;
+      uint32_t start_collseq;
+      uint32_t end_collseq;
+
+      /* Equivalence Classes and Character Classes can't be a range
+	 start/end.  */
+      if (BE (start_elem->type == EQUIV_CLASS || start_elem->type == CHAR_CLASS
+	      || end_elem->type == EQUIV_CLASS || end_elem->type == CHAR_CLASS,
+	      0))
+	return REG_ERANGE;
+
+      start_collseq = lookup_collation_sequence_value (start_elem);
+      end_collseq = lookup_collation_sequence_value (end_elem);
+      /* Check start/end collation sequence values.  */
+      if (BE (start_collseq == UINT_MAX || end_collseq == UINT_MAX, 0))
+	return REG_ECOLLATE;
+      if (BE ((syntax & RE_NO_EMPTY_RANGES) && start_collseq > end_collseq, 0))
+	return REG_ERANGE;
+
+      /* Got valid collation sequence values, add them as a new entry.
+	 However, if we have no collation elements, and the character set
+	 is single byte, the single byte character set that we
+	 build below suffices. */
+      if (nrules > 0 || dfa->mb_cur_max > 1)
+	{
+          /* Check the space of the arrays.  */
+          if (BE (*range_alloc == mbcset->nranges, 0))
+	    {
+	      /* There is not enough space, need realloc.  */
+	      uint32_t *new_array_start;
+	      uint32_t *new_array_end;
+	      int new_nranges;
+
+	      /* +1 in case of mbcset->nranges is 0.  */
+	      new_nranges = 2 * mbcset->nranges + 1;
+	      new_array_start = re_realloc (mbcset->range_starts, uint32_t,
+					    new_nranges);
+	      new_array_end = re_realloc (mbcset->range_ends, uint32_t,
+				          new_nranges);
+
+	      if (BE (new_array_start == NULL || new_array_end == NULL, 0))
+	        return REG_ESPACE;
+
+	      mbcset->range_starts = new_array_start;
+	      mbcset->range_ends = new_array_end;
+	      *range_alloc = new_nranges;
+	    }
+
+          mbcset->range_starts[mbcset->nranges] = start_collseq;
+          mbcset->range_ends[mbcset->nranges++] = end_collseq;
+	}
+
+      /* Build the table for single byte characters.  */
+      for (ch = 0; ch < SBC_MAX; ch++)
+	{
+	  uint32_t ch_collseq;
+	  /*
+	  if (MB_CUR_MAX == 1)
+	  */
+	  if (nrules == 0)
+	    ch_collseq = collseqmb[ch];
+	  else
+	    ch_collseq = __collseq_table_lookup (collseqwc, __btowc (ch));
+	  if (start_collseq <= ch_collseq && ch_collseq <= end_collseq)
+	    bitset_set (sbcset, ch);
+	}
+      return REG_NOERROR;
+    }
+
+  /* Local function for parse_bracket_exp used in _LIBC environement.
+     Build the collating element which is represented by NAME.
+     The result are written to MBCSET and SBCSET.
+     COLL_SYM_ALLOC is the allocated size of mbcset->coll_sym, is a
+     pointer argument sinse we may update it.  */
+
+  auto inline reg_errcode_t
+  __attribute ((always_inline))
+  build_collating_symbol (sbcset, mbcset, coll_sym_alloc, name)
+	 re_charset_t *mbcset;
+	 int *coll_sym_alloc;
+	 bitset_t sbcset;
+	 const unsigned char *name;
+    {
+      int32_t elem, idx;
+      size_t name_len = strlen ((const char *) name);
+      if (nrules != 0)
+	{
+	  elem = seek_collating_symbol_entry (name, name_len);
+	  if (symb_table[2 * elem] != 0)
+	    {
+	      /* We found the entry.  */
+	      idx = symb_table[2 * elem + 1];
+	      /* Skip the name of collating element name.  */
+	      idx += 1 + extra[idx];
+	    }
+	  else if (symb_table[2 * elem] == 0 && name_len == 1)
+	    {
+	      /* No valid character, treat it as a normal
+		 character.  */
+	      bitset_set (sbcset, name[0]);
+	      return REG_NOERROR;
+	    }
+	  else
+	    return REG_ECOLLATE;
+
+	  /* Got valid collation sequence, add it as a new entry.  */
+	  /* Check the space of the arrays.  */
+	  if (BE (*coll_sym_alloc == mbcset->ncoll_syms, 0))
+	    {
+	      /* Not enough, realloc it.  */
+	      /* +1 in case of mbcset->ncoll_syms is 0.  */
+	      int new_coll_sym_alloc = 2 * mbcset->ncoll_syms + 1;
+	      /* Use realloc since mbcset->coll_syms is NULL
+		 if *alloc == 0.  */
+	      int32_t *new_coll_syms = re_realloc (mbcset->coll_syms, int32_t,
+						   new_coll_sym_alloc);
+	      if (BE (new_coll_syms == NULL, 0))
+		return REG_ESPACE;
+	      mbcset->coll_syms = new_coll_syms;
+	      *coll_sym_alloc = new_coll_sym_alloc;
+	    }
+	  mbcset->coll_syms[mbcset->ncoll_syms++] = idx;
+	  return REG_NOERROR;
+	}
+      else
+	{
+	  if (BE (name_len != 1, 0))
+	    return REG_ECOLLATE;
+	  else
+	    {
+	      bitset_set (sbcset, name[0]);
+	      return REG_NOERROR;
+	    }
+	}
+    }
+#endif
+
+  re_token_t br_token;
+  re_bitset_ptr_t sbcset;
+#ifdef RE_ENABLE_I18N
+  re_charset_t *mbcset;
+  int coll_sym_alloc = 0, range_alloc = 0, mbchar_alloc = 0;
+  int equiv_class_alloc = 0, char_class_alloc = 0;
+#endif /* not RE_ENABLE_I18N */
+  int non_match = 0;
+  bin_tree_t *work_tree;
+  int token_len;
+  int first_round = 1;
+#ifdef _LIBC
+  collseqmb = (const unsigned char *)
+    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB);
+  nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
+  if (nrules)
+    {
+      /*
+      if (MB_CUR_MAX > 1)
+      */
+      collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC);
+      table_size = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_SYMB_HASH_SIZEMB);
+      symb_table = (const int32_t *) _NL_CURRENT (LC_COLLATE,
+						  _NL_COLLATE_SYMB_TABLEMB);
+      extra = (const unsigned char *) _NL_CURRENT (LC_COLLATE,
+						   _NL_COLLATE_SYMB_EXTRAMB);
+    }
+#endif
+  sbcset = (re_bitset_ptr_t) calloc (sizeof (bitset_t), 1);
+#ifdef RE_ENABLE_I18N
+  mbcset = (re_charset_t *) calloc (sizeof (re_charset_t), 1);
+#endif /* RE_ENABLE_I18N */
+#ifdef RE_ENABLE_I18N
+  if (BE (sbcset == NULL || mbcset == NULL, 0))
+#else
+  if (BE (sbcset == NULL, 0))
+#endif /* RE_ENABLE_I18N */
+    {
+      *err = REG_ESPACE;
+      return NULL;
+    }
+
+  token_len = peek_token_bracket (token, regexp, syntax);
+  if (BE (token->type == END_OF_RE, 0))
+    {
+      *err = REG_BADPAT;
+      goto parse_bracket_exp_free_return;
+    }
+  if (token->type == OP_NON_MATCH_LIST)
+    {
+#ifdef RE_ENABLE_I18N
+      mbcset->non_match = 1;
+#endif /* not RE_ENABLE_I18N */
+      non_match = 1;
+      if (syntax & RE_HAT_LISTS_NOT_NEWLINE)
+	bitset_set (sbcset, '\0');
+      re_string_skip_bytes (regexp, token_len); /* Skip a token.  */
+      token_len = peek_token_bracket (token, regexp, syntax);
+      if (BE (token->type == END_OF_RE, 0))
+	{
+	  *err = REG_BADPAT;
+	  goto parse_bracket_exp_free_return;
+	}
+    }
+
+  /* We treat the first ']' as a normal character.  */
+  if (token->type == OP_CLOSE_BRACKET)
+    token->type = CHARACTER;
+
+  while (1)
+    {
+      bracket_elem_t start_elem, end_elem;
+      unsigned char start_name_buf[BRACKET_NAME_BUF_SIZE];
+      unsigned char end_name_buf[BRACKET_NAME_BUF_SIZE];
+      reg_errcode_t ret;
+      int token_len2 = 0, is_range_exp = 0;
+      re_token_t token2;
+
+      start_elem.opr.name = start_name_buf;
+      ret = parse_bracket_element (&start_elem, regexp, token, token_len, dfa,
+				   syntax, first_round);
+      if (BE (ret != REG_NOERROR, 0))
+	{
+	  *err = ret;
+	  goto parse_bracket_exp_free_return;
+	}
+      first_round = 0;
+
+      /* Get information about the next token.  We need it in any case.  */
+      token_len = peek_token_bracket (token, regexp, syntax);
+
+      /* Do not check for ranges if we know they are not allowed.  */
+      if (start_elem.type != CHAR_CLASS && start_elem.type != EQUIV_CLASS)
+	{
+	  if (BE (token->type == END_OF_RE, 0))
+	    {
+	      *err = REG_EBRACK;
+	      goto parse_bracket_exp_free_return;
+	    }
+	  if (token->type == OP_CHARSET_RANGE)
+	    {
+	      re_string_skip_bytes (regexp, token_len); /* Skip '-'.  */
+	      token_len2 = peek_token_bracket (&token2, regexp, syntax);
+	      if (BE (token2.type == END_OF_RE, 0))
+		{
+		  *err = REG_EBRACK;
+		  goto parse_bracket_exp_free_return;
+		}
+	      if (token2.type == OP_CLOSE_BRACKET)
+		{
+		  /* We treat the last '-' as a normal character.  */
+		  re_string_skip_bytes (regexp, -token_len);
+		  token->type = CHARACTER;
+		}
+	      else
+		is_range_exp = 1;
+	    }
+	}
+
+      if (is_range_exp == 1)
+	{
+	  end_elem.opr.name = end_name_buf;
+	  ret = parse_bracket_element (&end_elem, regexp, &token2, token_len2,
+				       dfa, syntax, 1);
+	  if (BE (ret != REG_NOERROR, 0))
+	    {
+	      *err = ret;
+	      goto parse_bracket_exp_free_return;
+	    }
+
+	  token_len = peek_token_bracket (token, regexp, syntax);
+
+#ifdef _LIBC
+	  *err = build_range_exp (sbcset, mbcset, &range_alloc,
+				  &start_elem, &end_elem);
+#else
+# ifdef RE_ENABLE_I18N
+	  *err = build_range_exp (sbcset,
+				  dfa->mb_cur_max > 1 ? mbcset : NULL,
+				  &range_alloc, &start_elem, &end_elem);
+# else
+	  *err = build_range_exp (sbcset, &start_elem, &end_elem);
+# endif
+#endif /* RE_ENABLE_I18N */
+	  if (BE (*err != REG_NOERROR, 0))
+	    goto parse_bracket_exp_free_return;
+	}
+      else
+	{
+	  switch (start_elem.type)
+	    {
+	    case SB_CHAR:
+	      bitset_set (sbcset, start_elem.opr.ch);
+	      break;
+#ifdef RE_ENABLE_I18N
+	    case MB_CHAR:
+	      /* Check whether the array has enough space.  */
+	      if (BE (mbchar_alloc == mbcset->nmbchars, 0))
+		{
+		  wchar_t *new_mbchars;
+		  /* Not enough, realloc it.  */
+		  /* +1 in case of mbcset->nmbchars is 0.  */
+		  mbchar_alloc = 2 * mbcset->nmbchars + 1;
+		  /* Use realloc since array is NULL if *alloc == 0.  */
+		  new_mbchars = re_realloc (mbcset->mbchars, wchar_t,
+					    mbchar_alloc);
+		  if (BE (new_mbchars == NULL, 0))
+		    goto parse_bracket_exp_espace;
+		  mbcset->mbchars = new_mbchars;
+		}
+	      mbcset->mbchars[mbcset->nmbchars++] = start_elem.opr.wch;
+	      break;
+#endif /* RE_ENABLE_I18N */
+	    case EQUIV_CLASS:
+	      *err = build_equiv_class (sbcset,
+#ifdef RE_ENABLE_I18N
+					mbcset, &equiv_class_alloc,
+#endif /* RE_ENABLE_I18N */
+					start_elem.opr.name);
+	      if (BE (*err != REG_NOERROR, 0))
+		goto parse_bracket_exp_free_return;
+	      break;
+	    case COLL_SYM:
+	      *err = build_collating_symbol (sbcset,
+#ifdef RE_ENABLE_I18N
+					     mbcset, &coll_sym_alloc,
+#endif /* RE_ENABLE_I18N */
+					     start_elem.opr.name);
+	      if (BE (*err != REG_NOERROR, 0))
+		goto parse_bracket_exp_free_return;
+	      break;
+	    case CHAR_CLASS:
+	      *err = build_charclass (regexp->trans, sbcset,
+#ifdef RE_ENABLE_I18N
+				      mbcset, &char_class_alloc,
+#endif /* RE_ENABLE_I18N */
+				      start_elem.opr.name, syntax);
+	      if (BE (*err != REG_NOERROR, 0))
+	       goto parse_bracket_exp_free_return;
+	      break;
+	    default:
+	      assert (0);
+	      break;
+	    }
+	}
+      if (BE (token->type == END_OF_RE, 0))
+	{
+	  *err = REG_EBRACK;
+	  goto parse_bracket_exp_free_return;
+	}
+      if (token->type == OP_CLOSE_BRACKET)
+	break;
+    }
+
+  re_string_skip_bytes (regexp, token_len); /* Skip a token.  */
+
+  /* If it is non-matching list.  */
+  if (non_match)
+    bitset_not (sbcset);
+
+#ifdef RE_ENABLE_I18N
+  /* Ensure only single byte characters are set.  */
+  if (dfa->mb_cur_max > 1)
+    bitset_mask (sbcset, dfa->sb_char);
+
+  if (mbcset->nmbchars || mbcset->ncoll_syms || mbcset->nequiv_classes
+      || mbcset->nranges || (dfa->mb_cur_max > 1 && (mbcset->nchar_classes
+						     || mbcset->non_match)))
+    {
+      bin_tree_t *mbc_tree;
+      int sbc_idx;
+      /* Build a tree for complex bracket.  */
+      dfa->has_mb_node = 1;
+      br_token.type = COMPLEX_BRACKET;
+      br_token.opr.mbcset = mbcset;
+      mbc_tree = create_token_tree (dfa, NULL, NULL, &br_token);
+      if (BE (mbc_tree == NULL, 0))
+	goto parse_bracket_exp_espace;
+      for (sbc_idx = 0; sbc_idx < BITSET_WORDS; ++sbc_idx)
+	if (sbcset[sbc_idx])
+	  break;
+      /* If there are no bits set in sbcset, there is no point
+	 of having both SIMPLE_BRACKET and COMPLEX_BRACKET.  */
+      if (sbc_idx < BITSET_WORDS)
+	{
+          /* Build a tree for simple bracket.  */
+          br_token.type = SIMPLE_BRACKET;
+          br_token.opr.sbcset = sbcset;
+          work_tree = create_token_tree (dfa, NULL, NULL, &br_token);
+          if (BE (work_tree == NULL, 0))
+            goto parse_bracket_exp_espace;
+
+          /* Then join them by ALT node.  */
+          work_tree = create_tree (dfa, work_tree, mbc_tree, OP_ALT);
+          if (BE (work_tree == NULL, 0))
+            goto parse_bracket_exp_espace;
+	}
+      else
+	{
+	  re_free (sbcset);
+	  work_tree = mbc_tree;
+	}
+    }
+  else
+#endif /* not RE_ENABLE_I18N */
+    {
+#ifdef RE_ENABLE_I18N
+      free_charset (mbcset);
+#endif
+      /* Build a tree for simple bracket.  */
+      br_token.type = SIMPLE_BRACKET;
+      br_token.opr.sbcset = sbcset;
+      work_tree = create_token_tree (dfa, NULL, NULL, &br_token);
+      if (BE (work_tree == NULL, 0))
+        goto parse_bracket_exp_espace;
+    }
+  return work_tree;
+
+ parse_bracket_exp_espace:
+  *err = REG_ESPACE;
+ parse_bracket_exp_free_return:
+  re_free (sbcset);
+#ifdef RE_ENABLE_I18N
+  free_charset (mbcset);
+#endif /* RE_ENABLE_I18N */
+  return NULL;
+}
+
+/* Parse an element in the bracket expression.  */
+
+static reg_errcode_t
+parse_bracket_element (bracket_elem_t *elem, re_string_t *regexp,
+		       re_token_t *token, int token_len, re_dfa_t *dfa,
+		       reg_syntax_t syntax, int accept_hyphen)
+{
+#ifdef RE_ENABLE_I18N
+  int cur_char_size;
+  cur_char_size = re_string_char_size_at (regexp, re_string_cur_idx (regexp));
+  if (cur_char_size > 1)
+    {
+      elem->type = MB_CHAR;
+      elem->opr.wch = re_string_wchar_at (regexp, re_string_cur_idx (regexp));
+      re_string_skip_bytes (regexp, cur_char_size);
+      return REG_NOERROR;
+    }
+#endif /* RE_ENABLE_I18N */
+  re_string_skip_bytes (regexp, token_len); /* Skip a token.  */
+  if (token->type == OP_OPEN_COLL_ELEM || token->type == OP_OPEN_CHAR_CLASS
+      || token->type == OP_OPEN_EQUIV_CLASS)
+    return parse_bracket_symbol (elem, regexp, token);
+  if (BE (token->type == OP_CHARSET_RANGE, 0) && !accept_hyphen)
+    {
+      /* A '-' must only appear as anything but a range indicator before
+	 the closing bracket.  Everything else is an error.  */
+      re_token_t token2;
+      (void) peek_token_bracket (&token2, regexp, syntax);
+      if (token2.type != OP_CLOSE_BRACKET)
+	/* The actual error value is not standardized since this whole
+	   case is undefined.  But ERANGE makes good sense.  */
+	return REG_ERANGE;
+    }
+  elem->type = SB_CHAR;
+  elem->opr.ch = token->opr.c;
+  return REG_NOERROR;
+}
+
+/* Parse a bracket symbol in the bracket expression.  Bracket symbols are
+   such as [:<character_class>:], [.<collating_element>.], and
+   [=<equivalent_class>=].  */
+
+static reg_errcode_t
+parse_bracket_symbol (bracket_elem_t *elem, re_string_t *regexp,
+		      re_token_t *token)
+{
+  unsigned char ch, delim = token->opr.c;
+  int i = 0;
+  if (re_string_eoi(regexp))
+    return REG_EBRACK;
+  for (;; ++i)
+    {
+      if (i >= BRACKET_NAME_BUF_SIZE)
+	return REG_EBRACK;
+      if (token->type == OP_OPEN_CHAR_CLASS)
+	ch = re_string_fetch_byte_case (regexp);
+      else
+	ch = re_string_fetch_byte (regexp);
+      if (re_string_eoi(regexp))
+	return REG_EBRACK;
+      if (ch == delim && re_string_peek_byte (regexp, 0) == ']')
+	break;
+      elem->opr.name[i] = ch;
+    }
+  re_string_skip_bytes (regexp, 1);
+  elem->opr.name[i] = '\0';
+  switch (token->type)
+    {
+    case OP_OPEN_COLL_ELEM:
+      elem->type = COLL_SYM;
+      break;
+    case OP_OPEN_EQUIV_CLASS:
+      elem->type = EQUIV_CLASS;
+      break;
+    case OP_OPEN_CHAR_CLASS:
+      elem->type = CHAR_CLASS;
+      break;
+    default:
+      break;
+    }
+  return REG_NOERROR;
+}
+
+  /* Helper function for parse_bracket_exp.
+     Build the equivalence class which is represented by NAME.
+     The result are written to MBCSET and SBCSET.
+     EQUIV_CLASS_ALLOC is the allocated size of mbcset->equiv_classes,
+     is a pointer argument sinse we may update it.  */
+
+static reg_errcode_t
+#ifdef RE_ENABLE_I18N
+build_equiv_class (bitset_t sbcset, re_charset_t *mbcset,
+		   int *equiv_class_alloc, const unsigned char *name)
+#else /* not RE_ENABLE_I18N */
+build_equiv_class (bitset_t sbcset, const unsigned char *name)
+#endif /* not RE_ENABLE_I18N */
+{
+#ifdef _LIBC
+  uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
+  if (nrules != 0)
+    {
+      const int32_t *table, *indirect;
+      const unsigned char *weights, *extra, *cp;
+      unsigned char char_buf[2];
+      int32_t idx1, idx2;
+      unsigned int ch;
+      size_t len;
+      /* This #include defines a local function!  */
+# include <locale/weight.h>
+      /* Calculate the index for equivalence class.  */
+      cp = name;
+      table = (const int32_t *) _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
+      weights = (const unsigned char *) _NL_CURRENT (LC_COLLATE,
+					       _NL_COLLATE_WEIGHTMB);
+      extra = (const unsigned char *) _NL_CURRENT (LC_COLLATE,
+						   _NL_COLLATE_EXTRAMB);
+      indirect = (const int32_t *) _NL_CURRENT (LC_COLLATE,
+						_NL_COLLATE_INDIRECTMB);
+      idx1 = findidx (&cp);
+      if (BE (idx1 == 0 || cp < name + strlen ((const char *) name), 0))
+	/* This isn't a valid character.  */
+	return REG_ECOLLATE;
+
+      /* Build single byte matcing table for this equivalence class.  */
+      char_buf[1] = (unsigned char) '\0';
+      len = weights[idx1];
+      for (ch = 0; ch < SBC_MAX; ++ch)
+	{
+	  char_buf[0] = ch;
+	  cp = char_buf;
+	  idx2 = findidx (&cp);
+/*
+	  idx2 = table[ch];
+*/
+	  if (idx2 == 0)
+	    /* This isn't a valid character.  */
+	    continue;
+	  if (len == weights[idx2])
+	    {
+	      int cnt = 0;
+	      while (cnt <= len &&
+		     weights[idx1 + 1 + cnt] == weights[idx2 + 1 + cnt])
+		++cnt;
+
+	      if (cnt > len)
+		bitset_set (sbcset, ch);
+	    }
+	}
+      /* Check whether the array has enough space.  */
+      if (BE (*equiv_class_alloc == mbcset->nequiv_classes, 0))
+	{
+	  /* Not enough, realloc it.  */
+	  /* +1 in case of mbcset->nequiv_classes is 0.  */
+	  int new_equiv_class_alloc = 2 * mbcset->nequiv_classes + 1;
+	  /* Use realloc since the array is NULL if *alloc == 0.  */
+	  int32_t *new_equiv_classes = re_realloc (mbcset->equiv_classes,
+						   int32_t,
+						   new_equiv_class_alloc);
+	  if (BE (new_equiv_classes == NULL, 0))
+	    return REG_ESPACE;
+	  mbcset->equiv_classes = new_equiv_classes;
+	  *equiv_class_alloc = new_equiv_class_alloc;
+	}
+      mbcset->equiv_classes[mbcset->nequiv_classes++] = idx1;
+    }
+  else
+#endif /* _LIBC */
+    {
+      if (BE (strlen ((const char *) name) != 1, 0))
+	return REG_ECOLLATE;
+      bitset_set (sbcset, *name);
+    }
+  return REG_NOERROR;
+}
+
+  /* Helper function for parse_bracket_exp.
+     Build the character class which is represented by NAME.
+     The result are written to MBCSET and SBCSET.
+     CHAR_CLASS_ALLOC is the allocated size of mbcset->char_classes,
+     is a pointer argument sinse we may update it.  */
+
+static reg_errcode_t
+#ifdef RE_ENABLE_I18N
+build_charclass (RE_TRANSLATE_TYPE trans, bitset_t sbcset,
+		 re_charset_t *mbcset, int *char_class_alloc,
+		 const unsigned char *class_name, reg_syntax_t syntax)
+#else /* not RE_ENABLE_I18N */
+build_charclass (RE_TRANSLATE_TYPE trans, bitset_t sbcset,
+		 const unsigned char *class_name, reg_syntax_t syntax)
+#endif /* not RE_ENABLE_I18N */
+{
+  int i;
+  const char *name = (const char *) class_name;
+
+  /* In case of REG_ICASE "upper" and "lower" match the both of
+     upper and lower cases.  */
+  if ((syntax & RE_ICASE)
+      && (strcmp (name, "upper") == 0 || strcmp (name, "lower") == 0))
+    name = "alpha";
+
+#ifdef RE_ENABLE_I18N
+  /* Check the space of the arrays.  */
+  if (BE (*char_class_alloc == mbcset->nchar_classes, 0))
+    {
+      /* Not enough, realloc it.  */
+      /* +1 in case of mbcset->nchar_classes is 0.  */
+      int new_char_class_alloc = 2 * mbcset->nchar_classes + 1;
+      /* Use realloc since array is NULL if *alloc == 0.  */
+      wctype_t *new_char_classes = re_realloc (mbcset->char_classes, wctype_t,
+					       new_char_class_alloc);
+      if (BE (new_char_classes == NULL, 0))
+	return REG_ESPACE;
+      mbcset->char_classes = new_char_classes;
+      *char_class_alloc = new_char_class_alloc;
+    }
+  mbcset->char_classes[mbcset->nchar_classes++] = __wctype (name);
+#endif /* RE_ENABLE_I18N */
+
+#define BUILD_CHARCLASS_LOOP(ctype_func)	\
+  do {						\
+    if (BE (trans != NULL, 0))			\
+      {						\
+	for (i = 0; i < SBC_MAX; ++i)		\
+  	  if (ctype_func (i))			\
+	    bitset_set (sbcset, trans[i]);	\
+      }						\
+    else					\
+      {						\
+	for (i = 0; i < SBC_MAX; ++i)		\
+  	  if (ctype_func (i))			\
+	    bitset_set (sbcset, i);		\
+      }						\
+  } while (0)
+
+  if (strcmp (name, "alnum") == 0)
+    BUILD_CHARCLASS_LOOP (isalnum);
+  else if (strcmp (name, "cntrl") == 0)
+    BUILD_CHARCLASS_LOOP (iscntrl);
+  else if (strcmp (name, "lower") == 0)
+    BUILD_CHARCLASS_LOOP (islower);
+  else if (strcmp (name, "space") == 0)
+    BUILD_CHARCLASS_LOOP (isspace);
+  else if (strcmp (name, "alpha") == 0)
+    BUILD_CHARCLASS_LOOP (isalpha);
+  else if (strcmp (name, "digit") == 0)
+    BUILD_CHARCLASS_LOOP (isdigit);
+  else if (strcmp (name, "print") == 0)
+    BUILD_CHARCLASS_LOOP (isprint);
+  else if (strcmp (name, "upper") == 0)
+    BUILD_CHARCLASS_LOOP (isupper);
+  else if (strcmp (name, "blank") == 0)
+    BUILD_CHARCLASS_LOOP (isblank);
+  else if (strcmp (name, "graph") == 0)
+    BUILD_CHARCLASS_LOOP (isgraph);
+  else if (strcmp (name, "punct") == 0)
+    BUILD_CHARCLASS_LOOP (ispunct);
+  else if (strcmp (name, "xdigit") == 0)
+    BUILD_CHARCLASS_LOOP (isxdigit);
+  else
+    return REG_ECTYPE;
+
+  return REG_NOERROR;
+}
+
+static bin_tree_t *
+build_charclass_op (re_dfa_t *dfa, RE_TRANSLATE_TYPE trans,
+		    const unsigned char *class_name,
+		    const unsigned char *extra, int non_match,
+		    reg_errcode_t *err)
+{
+  re_bitset_ptr_t sbcset;
+#ifdef RE_ENABLE_I18N
+  re_charset_t *mbcset;
+  int alloc = 0;
+#endif /* not RE_ENABLE_I18N */
+  reg_errcode_t ret;
+  re_token_t br_token;
+  bin_tree_t *tree;
+
+  sbcset = (re_bitset_ptr_t) calloc (sizeof (bitset_t), 1);
+#ifdef RE_ENABLE_I18N
+  mbcset = (re_charset_t *) calloc (sizeof (re_charset_t), 1);
+#endif /* RE_ENABLE_I18N */
+
+#ifdef RE_ENABLE_I18N
+  if (BE (sbcset == NULL || mbcset == NULL, 0))
+#else /* not RE_ENABLE_I18N */
+  if (BE (sbcset == NULL, 0))
+#endif /* not RE_ENABLE_I18N */
+    {
+      *err = REG_ESPACE;
+      return NULL;
+    }
+
+  if (non_match)
+    {
+#ifdef RE_ENABLE_I18N
+      /*
+      if (syntax & RE_HAT_LISTS_NOT_NEWLINE)
+	bitset_set(cset->sbcset, '\0');
+      */
+      mbcset->non_match = 1;
+#endif /* not RE_ENABLE_I18N */
+    }
+
+  /* We don't care the syntax in this case.  */
+  ret = build_charclass (trans, sbcset,
+#ifdef RE_ENABLE_I18N
+			 mbcset, &alloc,
+#endif /* RE_ENABLE_I18N */
+			 class_name, 0);
+
+  if (BE (ret != REG_NOERROR, 0))
+    {
+      re_free (sbcset);
+#ifdef RE_ENABLE_I18N
+      free_charset (mbcset);
+#endif /* RE_ENABLE_I18N */
+      *err = ret;
+      return NULL;
+    }
+  /* \w match '_' also.  */
+  for (; *extra; extra++)
+    bitset_set (sbcset, *extra);
+
+  /* If it is non-matching list.  */
+  if (non_match)
+    bitset_not (sbcset);
+
+#ifdef RE_ENABLE_I18N
+  /* Ensure only single byte characters are set.  */
+  if (dfa->mb_cur_max > 1)
+    bitset_mask (sbcset, dfa->sb_char);
+#endif
+
+  /* Build a tree for simple bracket.  */
+  br_token.type = SIMPLE_BRACKET;
+  br_token.opr.sbcset = sbcset;
+  tree = create_token_tree (dfa, NULL, NULL, &br_token);
+  if (BE (tree == NULL, 0))
+    goto build_word_op_espace;
+
+#ifdef RE_ENABLE_I18N
+  if (dfa->mb_cur_max > 1)
+    {
+      bin_tree_t *mbc_tree;
+      /* Build a tree for complex bracket.  */
+      br_token.type = COMPLEX_BRACKET;
+      br_token.opr.mbcset = mbcset;
+      dfa->has_mb_node = 1;
+      mbc_tree = create_token_tree (dfa, NULL, NULL, &br_token);
+      if (BE (mbc_tree == NULL, 0))
+	goto build_word_op_espace;
+      /* Then join them by ALT node.  */
+      tree = create_tree (dfa, tree, mbc_tree, OP_ALT);
+      if (BE (mbc_tree != NULL, 1))
+	return tree;
+    }
+  else
+    {
+      free_charset (mbcset);
+      return tree;
+    }
+#else /* not RE_ENABLE_I18N */
+  return tree;
+#endif /* not RE_ENABLE_I18N */
+
+ build_word_op_espace:
+  re_free (sbcset);
+#ifdef RE_ENABLE_I18N
+  free_charset (mbcset);
+#endif /* RE_ENABLE_I18N */
+  *err = REG_ESPACE;
+  return NULL;
+}
+
+/* This is intended for the expressions like "a{1,3}".
+   Fetch a number from `input', and return the number.
+   Return -1, if the number field is empty like "{,1}".
+   Return -2, If an error is occured.  */
+
+static int
+fetch_number (re_string_t *input, re_token_t *token, reg_syntax_t syntax)
+{
+  int num = -1;
+  unsigned char c;
+  while (1)
+    {
+      fetch_token (token, input, syntax);
+      c = token->opr.c;
+      if (BE (token->type == END_OF_RE, 0))
+	return -2;
+      if (token->type == OP_CLOSE_DUP_NUM || c == ',')
+	break;
+      num = ((token->type != CHARACTER || c < '0' || '9' < c || num == -2)
+	     ? -2 : ((num == -1) ? c - '0' : num * 10 + c - '0'));
+      num = (num > RE_DUP_MAX) ? -2 : num;
+    }
+  return num;
+}
+
+#ifdef RE_ENABLE_I18N
+static void
+free_charset (re_charset_t *cset)
+{
+  re_free (cset->mbchars);
+# ifdef _LIBC
+  re_free (cset->coll_syms);
+  re_free (cset->equiv_classes);
+  re_free (cset->range_starts);
+  re_free (cset->range_ends);
+# endif
+  re_free (cset->char_classes);
+  re_free (cset);
+}
+#endif /* RE_ENABLE_I18N */
+
+/* Functions for binary tree operation.  */
+
+/* Create a tree node.  */
+
+static bin_tree_t *
+create_tree (re_dfa_t *dfa, bin_tree_t *left, bin_tree_t *right,
+	     re_token_type_t type)
+{
+  re_token_t t;
+  t.type = type;
+  return create_token_tree (dfa, left, right, &t);
+}
+
+static bin_tree_t *
+create_token_tree (re_dfa_t *dfa, bin_tree_t *left, bin_tree_t *right,
+		   const re_token_t *token)
+{
+  bin_tree_t *tree;
+  if (BE (dfa->str_tree_storage_idx == BIN_TREE_STORAGE_SIZE, 0))
+    {
+      bin_tree_storage_t *storage = re_malloc (bin_tree_storage_t, 1);
+
+      if (storage == NULL)
+	return NULL;
+      storage->next = dfa->str_tree_storage;
+      dfa->str_tree_storage = storage;
+      dfa->str_tree_storage_idx = 0;
+    }
+  tree = &dfa->str_tree_storage->data[dfa->str_tree_storage_idx++];
+
+  tree->parent = NULL;
+  tree->left = left;
+  tree->right = right;
+  tree->token = *token;
+  tree->token.duplicated = 0;
+  tree->token.opt_subexp = 0;
+  tree->first = NULL;
+  tree->next = NULL;
+  tree->node_idx = -1;
+
+  if (left != NULL)
+    left->parent = tree;
+  if (right != NULL)
+    right->parent = tree;
+  return tree;
+}
+
+/* Mark the tree SRC as an optional subexpression.
+   To be called from preorder or postorder.  */
+
+static reg_errcode_t
+mark_opt_subexp (void *extra, bin_tree_t *node)
+{
+  int idx = (int) (long) extra;
+  if (node->token.type == SUBEXP && node->token.opr.idx == idx)
+    node->token.opt_subexp = 1;
+
+  return REG_NOERROR;
+}
+
+/* Free the allocated memory inside NODE. */
+
+static void
+free_token (re_token_t *node)
+{
+#ifdef RE_ENABLE_I18N
+  if (node->type == COMPLEX_BRACKET && node->duplicated == 0)
+    free_charset (node->opr.mbcset);
+  else
+#endif /* RE_ENABLE_I18N */
+    if (node->type == SIMPLE_BRACKET && node->duplicated == 0)
+      re_free (node->opr.sbcset);
+}
+
+/* Worker function for tree walking.  Free the allocated memory inside NODE
+   and its children. */
+
+static reg_errcode_t
+free_tree (void *extra, bin_tree_t *node)
+{
+  free_token (&node->token);
+  return REG_NOERROR;
+}
+
+
+/* Duplicate the node SRC, and return new node.  This is a preorder
+   visit similar to the one implemented by the generic visitor, but
+   we need more infrastructure to maintain two parallel trees --- so,
+   it's easier to duplicate.  */
+
+static bin_tree_t *
+duplicate_tree (const bin_tree_t *root, re_dfa_t *dfa)
+{
+  const bin_tree_t *node;
+  bin_tree_t *dup_root;
+  bin_tree_t **p_new = &dup_root, *dup_node = root->parent;
+
+  for (node = root; ; )
+    {
+      /* Create a new tree and link it back to the current parent.  */
+      *p_new = create_token_tree (dfa, NULL, NULL, &node->token);
+      if (*p_new == NULL)
+	return NULL;
+      (*p_new)->parent = dup_node;
+      (*p_new)->token.duplicated = 1;
+      dup_node = *p_new;
+
+      /* Go to the left node, or up and to the right.  */
+      if (node->left)
+	{
+	  node = node->left;
+	  p_new = &dup_node->left;
+	}
+      else
+	{
+	  const bin_tree_t *prev = NULL;
+	  while (node->right == prev || node->right == NULL)
+	    {
+	      prev = node;
+	      node = node->parent;
+	      dup_node = dup_node->parent;
+	      if (!node)
+	        return dup_root;
+	    }
+	  node = node->right;
+	  p_new = &dup_node->right;
+	}
+    }
+}
diff --git a/Build/source/texk/chktex/regex/regex.c b/Build/source/texk/chktex/regex/regex.c
new file mode 100644
index 00000000000..d816df97794
--- /dev/null
+++ b/Build/source/texk/chktex/regex/regex.c
@@ -0,0 +1,31 @@
+/* Extended regular expression matching and search library.
+   Copyright (C) 2002, 2003, 2005 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+/* On some systems, limits.h sets RE_DUP_MAX to a lower value than
+   GNU regex allows.  Include it before <regex.h>, which correctly
+   #undefs RE_DUP_MAX and sets it to the right value.  */
+#include <limits.h>
+
+#include <regex/regex.h>
+#include <regex/regex_internal.h>
+
+#include <regex/regex_internal.c>
+#include <regex/regcomp.c>
+#include <regex/regexec.c>
diff --git a/Build/source/texk/chktex/regex/regex.h b/Build/source/texk/chktex/regex/regex.h
new file mode 100644
index 00000000000..807c404ec24
--- /dev/null
+++ b/Build/source/texk/chktex/regex/regex.h
@@ -0,0 +1,556 @@
+/* Definitions for data structures and routines for the regular
+   expression library.
+   Copyright (C) 1985,1989-93,1995-98,2000,2001,2002,2003,2005,2006
+   Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _REGEX_H
+#define _REGEX_H 1
+
+#include <sys/types.h>
+
+/* Allow the use in C++ code.  */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* The following two types have to be signed and unsigned integer type
+   wide enough to hold a value of a pointer.  For most ANSI compilers
+   ptrdiff_t and size_t should be likely OK.  Still size of these two
+   types is 2 for Microsoft C.  Ugh... */
+typedef long int s_reg_t;
+typedef unsigned long int active_reg_t;
+
+/* The following bits are used to determine the regexp syntax we
+   recognize.  The set/not-set meanings are chosen so that Emacs syntax
+   remains the value 0.  The bits are given in alphabetical order, and
+   the definitions shifted by one from the previous bit; thus, when we
+   add or remove a bit, only one other definition need change.  */
+typedef unsigned long int reg_syntax_t;
+
+/* If this bit is not set, then \ inside a bracket expression is literal.
+   If set, then such a \ quotes the following character.  */
+#define RE_BACKSLASH_ESCAPE_IN_LISTS ((unsigned long int) 1)
+
+/* If this bit is not set, then + and ? are operators, and \+ and \? are
+     literals.
+   If set, then \+ and \? are operators and + and ? are literals.  */
+#define RE_BK_PLUS_QM (RE_BACKSLASH_ESCAPE_IN_LISTS << 1)
+
+/* If this bit is set, then character classes are supported.  They are:
+     [:alpha:], [:upper:], [:lower:],  [:digit:], [:alnum:], [:xdigit:],
+     [:space:], [:print:], [:punct:], [:graph:], and [:cntrl:].
+   If not set, then character classes are not supported.  */
+#define RE_CHAR_CLASSES (RE_BK_PLUS_QM << 1)
+
+/* If this bit is set, then ^ and $ are always anchors (outside bracket
+     expressions, of course).
+   If this bit is not set, then it depends:
+        ^  is an anchor if it is at the beginning of a regular
+           expression or after an open-group or an alternation operator;
+        $  is an anchor if it is at the end of a regular expression, or
+           before a close-group or an alternation operator.
+
+   This bit could be (re)combined with RE_CONTEXT_INDEP_OPS, because
+   POSIX draft 11.2 says that * etc. in leading positions is undefined.
+   We already implemented a previous draft which made those constructs
+   invalid, though, so we haven't changed the code back.  */
+#define RE_CONTEXT_INDEP_ANCHORS (RE_CHAR_CLASSES << 1)
+
+/* If this bit is set, then special characters are always special
+     regardless of where they are in the pattern.
+   If this bit is not set, then special characters are special only in
+     some contexts; otherwise they are ordinary.  Specifically,
+     * + ? and intervals are only special when not after the beginning,
+     open-group, or alternation operator.  */
+#define RE_CONTEXT_INDEP_OPS (RE_CONTEXT_INDEP_ANCHORS << 1)
+
+/* If this bit is set, then *, +, ?, and { cannot be first in an re or
+     immediately after an alternation or begin-group operator.  */
+#define RE_CONTEXT_INVALID_OPS (RE_CONTEXT_INDEP_OPS << 1)
+
+/* If this bit is set, then . matches newline.
+   If not set, then it doesn't.  */
+#define RE_DOT_NEWLINE (RE_CONTEXT_INVALID_OPS << 1)
+
+/* If this bit is set, then . doesn't match NUL.
+   If not set, then it does.  */
+#define RE_DOT_NOT_NULL (RE_DOT_NEWLINE << 1)
+
+/* If this bit is set, nonmatching lists [^...] do not match newline.
+   If not set, they do.  */
+#define RE_HAT_LISTS_NOT_NEWLINE (RE_DOT_NOT_NULL << 1)
+
+/* If this bit is set, either \{...\} or {...} defines an
+     interval, depending on RE_NO_BK_BRACES.
+   If not set, \{, \}, {, and } are literals.  */
+#define RE_INTERVALS (RE_HAT_LISTS_NOT_NEWLINE << 1)
+
+/* If this bit is set, +, ? and | aren't recognized as operators.
+   If not set, they are.  */
+#define RE_LIMITED_OPS (RE_INTERVALS << 1)
+
+/* If this bit is set, newline is an alternation operator.
+   If not set, newline is literal.  */
+#define RE_NEWLINE_ALT (RE_LIMITED_OPS << 1)
+
+/* If this bit is set, then `{...}' defines an interval, and \{ and \}
+     are literals.
+  If not set, then `\{...\}' defines an interval.  */
+#define RE_NO_BK_BRACES (RE_NEWLINE_ALT << 1)
+
+/* If this bit is set, (...) defines a group, and \( and \) are literals.
+   If not set, \(...\) defines a group, and ( and ) are literals.  */
+#define RE_NO_BK_PARENS (RE_NO_BK_BRACES << 1)
+
+/* If this bit is set, then \<digit> matches <digit>.
+   If not set, then \<digit> is a back-reference.  */
+#define RE_NO_BK_REFS (RE_NO_BK_PARENS << 1)
+
+/* If this bit is set, then | is an alternation operator, and \| is literal.
+   If not set, then \| is an alternation operator, and | is literal.  */
+#define RE_NO_BK_VBAR (RE_NO_BK_REFS << 1)
+
+/* If this bit is set, then an ending range point collating higher
+     than the starting range point, as in [z-a], is invalid.
+   If not set, then when ending range point collates higher than the
+     starting range point, the range is ignored.  */
+#define RE_NO_EMPTY_RANGES (RE_NO_BK_VBAR << 1)
+
+/* If this bit is set, then an unmatched ) is ordinary.
+   If not set, then an unmatched ) is invalid.  */
+#define RE_UNMATCHED_RIGHT_PAREN_ORD (RE_NO_EMPTY_RANGES << 1)
+
+/* If this bit is set, succeed as soon as we match the whole pattern,
+   without further backtracking.  */
+#define RE_NO_POSIX_BACKTRACKING (RE_UNMATCHED_RIGHT_PAREN_ORD << 1)
+
+/* If this bit is set, do not process the GNU regex operators.
+   If not set, then the GNU regex operators are recognized. */
+#define RE_NO_GNU_OPS (RE_NO_POSIX_BACKTRACKING << 1)
+
+/* If this bit is set, turn on internal regex debugging.
+   If not set, and debugging was on, turn it off.
+   This only works if regex.c is compiled -DDEBUG.
+   We define this bit always, so that all that's needed to turn on
+   debugging is to recompile regex.c; the calling code can always have
+   this bit set, and it won't affect anything in the normal case. */
+#define RE_DEBUG (RE_NO_GNU_OPS << 1)
+
+/* If this bit is set, a syntactically invalid interval is treated as
+   a string of ordinary characters.  For example, the ERE 'a{1' is
+   treated as 'a\{1'.  */
+#define RE_INVALID_INTERVAL_ORD (RE_DEBUG << 1)
+
+/* If this bit is set, then ignore case when matching.
+   If not set, then case is significant.  */
+#define RE_ICASE (RE_INVALID_INTERVAL_ORD << 1)
+
+/* This bit is used internally like RE_CONTEXT_INDEP_ANCHORS but only
+   for ^, because it is difficult to scan the regex backwards to find
+   whether ^ should be special.  */
+#define RE_CARET_ANCHORS_HERE (RE_ICASE << 1)
+
+/* If this bit is set, then \{ cannot be first in an bre or
+   immediately after an alternation or begin-group operator.  */
+#define RE_CONTEXT_INVALID_DUP (RE_CARET_ANCHORS_HERE << 1)
+
+/* If this bit is set, then no_sub will be set to 1 during
+   re_compile_pattern.  */
+#define RE_NO_SUB (RE_CONTEXT_INVALID_DUP << 1)
+
+/* This global variable defines the particular regexp syntax to use (for
+   some interfaces).  When a regexp is compiled, the syntax used is
+   stored in the pattern buffer, so changing this does not affect
+   already-compiled regexps.  */
+extern reg_syntax_t re_syntax_options;
+
+/* Define combinations of the above bits for the standard possibilities.
+   (The [[[ comments delimit what gets put into the Texinfo file, so
+   don't delete them!)  */
+/* [[[begin syntaxes]]] */
+#define RE_SYNTAX_EMACS 0
+
+#define RE_SYNTAX_AWK							\
+  (RE_BACKSLASH_ESCAPE_IN_LISTS   | RE_DOT_NOT_NULL			\
+   | RE_NO_BK_PARENS              | RE_NO_BK_REFS			\
+   | RE_NO_BK_VBAR                | RE_NO_EMPTY_RANGES			\
+   | RE_DOT_NEWLINE		  | RE_CONTEXT_INDEP_ANCHORS		\
+   | RE_UNMATCHED_RIGHT_PAREN_ORD | RE_NO_GNU_OPS)
+
+#define RE_SYNTAX_GNU_AWK						\
+  ((RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DEBUG)	\
+   & ~(RE_DOT_NOT_NULL | RE_INTERVALS | RE_CONTEXT_INDEP_OPS		\
+       | RE_CONTEXT_INVALID_OPS ))
+
+#define RE_SYNTAX_POSIX_AWK						\
+  (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS		\
+   | RE_INTERVALS	    | RE_NO_GNU_OPS)
+
+#define RE_SYNTAX_GREP							\
+  (RE_BK_PLUS_QM              | RE_CHAR_CLASSES				\
+   | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS				\
+   | RE_NEWLINE_ALT)
+
+#define RE_SYNTAX_EGREP							\
+  (RE_CHAR_CLASSES        | RE_CONTEXT_INDEP_ANCHORS			\
+   | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE			\
+   | RE_NEWLINE_ALT       | RE_NO_BK_PARENS				\
+   | RE_NO_BK_VBAR)
+
+#define RE_SYNTAX_POSIX_EGREP						\
+  (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES			\
+   | RE_INVALID_INTERVAL_ORD)
+
+/* P1003.2/D11.2, section 4.20.7.1, lines 5078ff.  */
+#define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC
+
+#define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC
+
+/* Syntax bits common to both basic and extended POSIX regex syntax.  */
+#define _RE_SYNTAX_POSIX_COMMON						\
+  (RE_CHAR_CLASSES | RE_DOT_NEWLINE      | RE_DOT_NOT_NULL		\
+   | RE_INTERVALS  | RE_NO_EMPTY_RANGES)
+
+#define RE_SYNTAX_POSIX_BASIC						\
+  (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM | RE_CONTEXT_INVALID_DUP)
+
+/* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
+   RE_LIMITED_OPS, i.e., \? \+ \| are not recognized.  Actually, this
+   isn't minimal, since other operators, such as \`, aren't disabled.  */
+#define RE_SYNTAX_POSIX_MINIMAL_BASIC					\
+  (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)
+
+#define RE_SYNTAX_POSIX_EXTENDED					\
+  (_RE_SYNTAX_POSIX_COMMON  | RE_CONTEXT_INDEP_ANCHORS			\
+   | RE_CONTEXT_INDEP_OPS   | RE_NO_BK_BRACES				\
+   | RE_NO_BK_PARENS        | RE_NO_BK_VBAR				\
+   | RE_CONTEXT_INVALID_OPS | RE_UNMATCHED_RIGHT_PAREN_ORD)
+
+/* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INDEP_OPS is
+   removed and RE_NO_BK_REFS is added.  */
+#define RE_SYNTAX_POSIX_MINIMAL_EXTENDED				\
+  (_RE_SYNTAX_POSIX_COMMON  | RE_CONTEXT_INDEP_ANCHORS			\
+   | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES				\
+   | RE_NO_BK_PARENS        | RE_NO_BK_REFS				\
+   | RE_NO_BK_VBAR	    | RE_UNMATCHED_RIGHT_PAREN_ORD)
+/* [[[end syntaxes]]] */
+
+/* Maximum number of duplicates an interval can allow.  Some systems
+   (erroneously) define this in other header files, but we want our
+   value, so remove any previous define.  */
+#ifdef RE_DUP_MAX
+# undef RE_DUP_MAX
+#endif
+/* If sizeof(int) == 2, then ((1 << 15) - 1) overflows.  */
+#define RE_DUP_MAX (0x7fff)
+
+
+/* POSIX `cflags' bits (i.e., information for `regcomp').  */
+
+/* If this bit is set, then use extended regular expression syntax.
+   If not set, then use basic regular expression syntax.  */
+#define REG_EXTENDED 1
+
+/* If this bit is set, then ignore case when matching.
+   If not set, then case is significant.  */
+#define REG_ICASE (REG_EXTENDED << 1)
+
+/* If this bit is set, then anchors do not match at newline
+     characters in the string.
+   If not set, then anchors do match at newlines.  */
+#define REG_NEWLINE (REG_ICASE << 1)
+
+/* If this bit is set, then report only success or fail in regexec.
+   If not set, then returns differ between not matching and errors.  */
+#define REG_NOSUB (REG_NEWLINE << 1)
+
+
+/* POSIX `eflags' bits (i.e., information for regexec).  */
+
+/* If this bit is set, then the beginning-of-line operator doesn't match
+     the beginning of the string (presumably because it's not the
+     beginning of a line).
+   If not set, then the beginning-of-line operator does match the
+     beginning of the string.  */
+#define REG_NOTBOL 1
+
+/* Like REG_NOTBOL, except for the end-of-line.  */
+#define REG_NOTEOL (1 << 1)
+
+/* Use PMATCH[0] to delimit the start and end of the search in the
+   buffer.  */
+#define REG_STARTEND (1 << 2)
+
+
+/* If any error codes are removed, changed, or added, update the
+   `re_error_msg' table in regex.c.  */
+typedef enum
+{
+#ifdef _XOPEN_SOURCE
+  REG_ENOSYS = -1,	/* This will never happen for this implementation.  */
+#endif
+
+  REG_NOERROR = 0,	/* Success.  */
+  REG_NOMATCH,		/* Didn't find a match (for regexec).  */
+
+  /* POSIX regcomp return error codes.  (In the order listed in the
+     standard.)  */
+  REG_BADPAT,		/* Invalid pattern.  */
+  REG_ECOLLATE,		/* Inalid collating element.  */
+  REG_ECTYPE,		/* Invalid character class name.  */
+  REG_EESCAPE,		/* Trailing backslash.  */
+  REG_ESUBREG,		/* Invalid back reference.  */
+  REG_EBRACK,		/* Unmatched left bracket.  */
+  REG_EPAREN,		/* Parenthesis imbalance.  */
+  REG_EBRACE,		/* Unmatched \{.  */
+  REG_BADBR,		/* Invalid contents of \{\}.  */
+  REG_ERANGE,		/* Invalid range end.  */
+  REG_ESPACE,		/* Ran out of memory.  */
+  REG_BADRPT,		/* No preceding re for repetition op.  */
+
+  /* Error codes we've added.  */
+  REG_EEND,		/* Premature end.  */
+  REG_ESIZE,		/* Compiled pattern bigger than 2^16 bytes.  */
+  REG_ERPAREN		/* Unmatched ) or \); not returned from regcomp.  */
+} reg_errcode_t;
+
+/* This data structure represents a compiled pattern.  Before calling
+   the pattern compiler, the fields `buffer', `allocated', `fastmap',
+   `translate', and `no_sub' can be set.  After the pattern has been
+   compiled, the `re_nsub' field is available.  All other fields are
+   private to the regex routines.  */
+
+#ifndef RE_TRANSLATE_TYPE
+# define RE_TRANSLATE_TYPE unsigned char *
+#endif
+
+struct re_pattern_buffer
+{
+  /* Space that holds the compiled pattern.  It is declared as
+     `unsigned char *' because its elements are sometimes used as
+     array indexes.  */
+  unsigned char *buffer;
+
+  /* Number of bytes to which `buffer' points.  */
+  unsigned long int allocated;
+
+  /* Number of bytes actually used in `buffer'.  */
+  unsigned long int used;
+
+  /* Syntax setting with which the pattern was compiled.  */
+  reg_syntax_t syntax;
+
+  /* Pointer to a fastmap, if any, otherwise zero.  re_search uses the
+     fastmap, if there is one, to skip over impossible starting points
+     for matches.  */
+  char *fastmap;
+
+  /* Either a translate table to apply to all characters before
+     comparing them, or zero for no translation.  The translation is
+     applied to a pattern when it is compiled and to a string when it
+     is matched.  */
+  RE_TRANSLATE_TYPE translate;
+
+  /* Number of subexpressions found by the compiler.  */
+  size_t re_nsub;
+
+  /* Zero if this pattern cannot match the empty string, one else.
+     Well, in truth it's used only in `re_search_2', to see whether or
+     not we should use the fastmap, so we don't set this absolutely
+     perfectly; see `re_compile_fastmap' (the `duplicate' case).  */
+  unsigned can_be_null : 1;
+
+  /* If REGS_UNALLOCATED, allocate space in the `regs' structure
+     for `max (RE_NREGS, re_nsub + 1)' groups.
+     If REGS_REALLOCATE, reallocate space if necessary.
+     If REGS_FIXED, use what's there.  */
+#define REGS_UNALLOCATED 0
+#define REGS_REALLOCATE 1
+#define REGS_FIXED 2
+  unsigned regs_allocated : 2;
+
+  /* Set to zero when `regex_compile' compiles a pattern; set to one
+     by `re_compile_fastmap' if it updates the fastmap.  */
+  unsigned fastmap_accurate : 1;
+
+  /* If set, `re_match_2' does not return information about
+     subexpressions.  */
+  unsigned no_sub : 1;
+
+  /* If set, a beginning-of-line anchor doesn't match at the beginning
+     of the string.  */
+  unsigned not_bol : 1;
+
+  /* Similarly for an end-of-line anchor.  */
+  unsigned not_eol : 1;
+
+  /* If true, an anchor at a newline matches.  */
+  unsigned newline_anchor : 1;
+};
+
+typedef struct re_pattern_buffer regex_t;
+
+/* Type for byte offsets within the string.  POSIX mandates this.  */
+typedef int regoff_t;
+
+
+/* This is the structure we store register match data in.  See
+   regex.texinfo for a full description of what registers match.  */
+struct re_registers
+{
+  unsigned num_regs;
+  regoff_t *start;
+  regoff_t *end;
+};
+
+
+/* If `regs_allocated' is REGS_UNALLOCATED in the pattern buffer,
+   `re_match_2' returns information about at least this many registers
+   the first time a `regs' structure is passed.  */
+#ifndef RE_NREGS
+# define RE_NREGS 30
+#endif
+
+
+/* POSIX specification for registers.  Aside from the different names than
+   `re_registers', POSIX uses an array of structures, instead of a
+   structure of arrays.  */
+typedef struct
+{
+  regoff_t rm_so;  /* Byte offset from string's start to substring's start.  */
+  regoff_t rm_eo;  /* Byte offset from string's start to substring's end.  */
+} regmatch_t;
+
+/* Declarations for routines.  */
+
+/* Sets the current default syntax to SYNTAX, and return the old syntax.
+   You can also simply assign to the `re_syntax_options' variable.  */
+extern reg_syntax_t re_set_syntax (reg_syntax_t __syntax);
+
+/* Compile the regular expression PATTERN, with length LENGTH
+   and syntax given by the global `re_syntax_options', into the buffer
+   BUFFER.  Return NULL if successful, and an error string if not.  */
+extern const char *re_compile_pattern (const char *__pattern, size_t __length,
+				       struct re_pattern_buffer *__buffer);
+
+
+/* Compile a fastmap for the compiled pattern in BUFFER; used to
+   accelerate searches.  Return 0 if successful and -2 if was an
+   internal error.  */
+extern int re_compile_fastmap (struct re_pattern_buffer *__buffer);
+
+
+/* Search in the string STRING (with length LENGTH) for the pattern
+   compiled into BUFFER.  Start searching at position START, for RANGE
+   characters.  Return the starting position of the match, -1 for no
+   match, or -2 for an internal error.  Also return register
+   information in REGS (if REGS and BUFFER->no_sub are nonzero).  */
+extern int re_search (struct re_pattern_buffer *__buffer, const char *__string,
+		      int __length, int __start, int __range,
+		      struct re_registers *__regs);
+
+
+/* Like `re_search', but search in the concatenation of STRING1 and
+   STRING2.  Also, stop searching at index START + STOP.  */
+extern int re_search_2 (struct re_pattern_buffer *__buffer,
+			const char *__string1, int __length1,
+			const char *__string2, int __length2, int __start,
+			int __range, struct re_registers *__regs, int __stop);
+
+
+/* Like `re_search', but return how many characters in STRING the regexp
+   in BUFFER matched, starting at position START.  */
+extern int re_match (struct re_pattern_buffer *__buffer, const char *__string,
+		     int __length, int __start, struct re_registers *__regs);
+
+
+/* Relates to `re_match' as `re_search_2' relates to `re_search'.  */
+extern int re_match_2 (struct re_pattern_buffer *__buffer,
+		       const char *__string1, int __length1,
+		       const char *__string2, int __length2, int __start,
+		       struct re_registers *__regs, int __stop);
+
+
+/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
+   ENDS.  Subsequent matches using BUFFER and REGS will use this memory
+   for recording register information.  STARTS and ENDS must be
+   allocated with malloc, and must each be at least `NUM_REGS * sizeof
+   (regoff_t)' bytes long.
+
+   If NUM_REGS == 0, then subsequent matches should allocate their own
+   register data.
+
+   Unless this function is called, the first search or match using
+   PATTERN_BUFFER will allocate its own register data, without
+   freeing the old data.  */
+extern void re_set_registers (struct re_pattern_buffer *__buffer,
+			      struct re_registers *__regs,
+			      unsigned int __num_regs,
+			      regoff_t *__starts, regoff_t *__ends);
+
+#if defined _REGEX_RE_COMP || defined _LIBC
+# ifndef _CRAY
+/* 4.2 bsd compatibility.  */
+extern char *re_comp (const char *);
+extern int re_exec (const char *);
+# endif
+#endif
+
+/* GCC 2.95 and later have "__restrict"; C99 compilers have
+   "restrict", and "configure" may have defined "restrict".  */
+#ifndef __restrict
+# if ! (2 < __GNUC__ || (2 == __GNUC__ && 95 <= __GNUC_MINOR__))
+#  if defined restrict || 199901L <= __STDC_VERSION__
+#   define __restrict restrict
+#  else
+#   define __restrict
+#  endif
+# endif
+#endif
+/* gcc 3.1 and up support the [restrict] syntax.  */
+#ifndef __restrict_arr
+# if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)) \
+     && !defined __GNUG__
+#  define __restrict_arr __restrict
+# else
+#  define __restrict_arr
+# endif
+#endif
+
+/* POSIX compatibility.  */
+extern int regcomp (regex_t *__restrict __preg,
+		    const char *__restrict __pattern,
+		    int __cflags);
+
+extern int regexec (const regex_t *__restrict __preg,
+		    const char *__restrict __string, size_t __nmatch,
+		    regmatch_t __pmatch[__restrict_arr],
+		    int __eflags);
+
+extern size_t regerror (int __errcode, const regex_t *__restrict __preg,
+			char *__restrict __errbuf, size_t __errbuf_size);
+
+extern void regfree (regex_t *__preg);
+
+
+#ifdef __cplusplus
+}
+#endif	/* C++ */
+
+#endif /* regex.h */
diff --git a/Build/source/texk/chktex/regex/regex_internal.c b/Build/source/texk/chktex/regex/regex_internal.c
new file mode 100644
index 00000000000..66154e0ceac
--- /dev/null
+++ b/Build/source/texk/chktex/regex/regex_internal.c
@@ -0,0 +1,1717 @@
+/* Extended regular expression matching and search library.
+   Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+static void re_string_construct_common (const char *str, int len,
+					re_string_t *pstr,
+					RE_TRANSLATE_TYPE trans, int icase,
+					const re_dfa_t *dfa) internal_function;
+static re_dfastate_t *create_ci_newstate (const re_dfa_t *dfa,
+					  const re_node_set *nodes,
+					  unsigned int hash) internal_function;
+static re_dfastate_t *create_cd_newstate (const re_dfa_t *dfa,
+					  const re_node_set *nodes,
+					  unsigned int context,
+					  unsigned int hash) internal_function;
+
+/* Functions for string operation.  */
+
+/* This function allocate the buffers.  It is necessary to call
+   re_string_reconstruct before using the object.  */
+
+static reg_errcode_t
+internal_function
+re_string_allocate (re_string_t *pstr, const char *str, int len, int init_len,
+		    RE_TRANSLATE_TYPE trans, int icase, const re_dfa_t *dfa)
+{
+  reg_errcode_t ret;
+  int init_buf_len;
+
+  /* Ensure at least one character fits into the buffers.  */
+  if (init_len < dfa->mb_cur_max)
+    init_len = dfa->mb_cur_max;
+  init_buf_len = (len + 1 < init_len) ? len + 1: init_len;
+  re_string_construct_common (str, len, pstr, trans, icase, dfa);
+
+  ret = re_string_realloc_buffers (pstr, init_buf_len);
+  if (BE (ret != REG_NOERROR, 0))
+    return ret;
+
+  pstr->word_char = dfa->word_char;
+  pstr->word_ops_used = dfa->word_ops_used;
+  pstr->mbs = pstr->mbs_allocated ? pstr->mbs : (unsigned char *) str;
+  pstr->valid_len = (pstr->mbs_allocated || dfa->mb_cur_max > 1) ? 0 : len;
+  pstr->valid_raw_len = pstr->valid_len;
+  return REG_NOERROR;
+}
+
+/* This function allocate the buffers, and initialize them.  */
+
+static reg_errcode_t
+internal_function
+re_string_construct (re_string_t *pstr, const char *str, int len,
+		     RE_TRANSLATE_TYPE trans, int icase, const re_dfa_t *dfa)
+{
+  reg_errcode_t ret;
+  memset (pstr, '\0', sizeof (re_string_t));
+  re_string_construct_common (str, len, pstr, trans, icase, dfa);
+
+  if (len > 0)
+    {
+      ret = re_string_realloc_buffers (pstr, len + 1);
+      if (BE (ret != REG_NOERROR, 0))
+	return ret;
+    }
+  pstr->mbs = pstr->mbs_allocated ? pstr->mbs : (unsigned char *) str;
+
+  if (icase)
+    {
+#ifdef RE_ENABLE_I18N
+      if (dfa->mb_cur_max > 1)
+	{
+	  while (1)
+	    {
+	      ret = build_wcs_upper_buffer (pstr);
+	      if (BE (ret != REG_NOERROR, 0))
+		return ret;
+	      if (pstr->valid_raw_len >= len)
+		break;
+	      if (pstr->bufs_len > pstr->valid_len + dfa->mb_cur_max)
+		break;
+	      ret = re_string_realloc_buffers (pstr, pstr->bufs_len * 2);
+	      if (BE (ret != REG_NOERROR, 0))
+		return ret;
+	    }
+	}
+      else
+#endif /* RE_ENABLE_I18N  */
+	build_upper_buffer (pstr);
+    }
+  else
+    {
+#ifdef RE_ENABLE_I18N
+      if (dfa->mb_cur_max > 1)
+	build_wcs_buffer (pstr);
+      else
+#endif /* RE_ENABLE_I18N  */
+	{
+	  if (trans != NULL)
+	    re_string_translate_buffer (pstr);
+	  else
+	    {
+	      pstr->valid_len = pstr->bufs_len;
+	      pstr->valid_raw_len = pstr->bufs_len;
+	    }
+	}
+    }
+
+  return REG_NOERROR;
+}
+
+/* Helper functions for re_string_allocate, and re_string_construct.  */
+
+static reg_errcode_t
+internal_function
+re_string_realloc_buffers (re_string_t *pstr, int new_buf_len)
+{
+#ifdef RE_ENABLE_I18N
+  if (pstr->mb_cur_max > 1)
+    {
+      wint_t *new_wcs = re_realloc (pstr->wcs, wint_t, new_buf_len);
+      if (BE (new_wcs == NULL, 0))
+	return REG_ESPACE;
+      pstr->wcs = new_wcs;
+      if (pstr->offsets != NULL)
+	{
+	  int *new_offsets = re_realloc (pstr->offsets, int, new_buf_len);
+	  if (BE (new_offsets == NULL, 0))
+	    return REG_ESPACE;
+	  pstr->offsets = new_offsets;
+	}
+    }
+#endif /* RE_ENABLE_I18N  */
+  if (pstr->mbs_allocated)
+    {
+      unsigned char *new_mbs = re_realloc (pstr->mbs, unsigned char,
+					   new_buf_len);
+      if (BE (new_mbs == NULL, 0))
+	return REG_ESPACE;
+      pstr->mbs = new_mbs;
+    }
+  pstr->bufs_len = new_buf_len;
+  return REG_NOERROR;
+}
+
+
+static void
+internal_function
+re_string_construct_common (const char *str, int len, re_string_t *pstr,
+			    RE_TRANSLATE_TYPE trans, int icase,
+			    const re_dfa_t *dfa)
+{
+  pstr->raw_mbs = (const unsigned char *) str;
+  pstr->len = len;
+  pstr->raw_len = len;
+  pstr->trans = trans;
+  pstr->icase = icase ? 1 : 0;
+  pstr->mbs_allocated = (trans != NULL || icase);
+  pstr->mb_cur_max = dfa->mb_cur_max;
+  pstr->is_utf8 = dfa->is_utf8;
+  pstr->map_notascii = dfa->map_notascii;
+  pstr->stop = pstr->len;
+  pstr->raw_stop = pstr->stop;
+}
+
+#ifdef RE_ENABLE_I18N
+
+/* Build wide character buffer PSTR->WCS.
+   If the byte sequence of the string are:
+     <mb1>(0), <mb1>(1), <mb2>(0), <mb2>(1), <sb3>
+   Then wide character buffer will be:
+     <wc1>   , WEOF    , <wc2>   , WEOF    , <wc3>
+   We use WEOF for padding, they indicate that the position isn't
+   a first byte of a multibyte character.
+
+   Note that this function assumes PSTR->VALID_LEN elements are already
+   built and starts from PSTR->VALID_LEN.  */
+
+static void
+internal_function
+build_wcs_buffer (re_string_t *pstr)
+{
+#ifdef _LIBC
+  unsigned char buf[MB_LEN_MAX];
+  assert (MB_LEN_MAX >= pstr->mb_cur_max);
+#else
+  unsigned char buf[64];
+#endif
+  mbstate_t prev_st;
+  int byte_idx, end_idx, remain_len;
+  size_t mbclen;
+
+  /* Build the buffers from pstr->valid_len to either pstr->len or
+     pstr->bufs_len.  */
+  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
+  for (byte_idx = pstr->valid_len; byte_idx < end_idx;)
+    {
+      wchar_t wc;
+      const char *p;
+
+      remain_len = end_idx - byte_idx;
+      prev_st = pstr->cur_state;
+      /* Apply the translation if we need.  */
+      if (BE (pstr->trans != NULL, 0))
+	{
+	  int i, ch;
+
+	  for (i = 0; i < pstr->mb_cur_max && i < remain_len; ++i)
+	    {
+	      ch = pstr->raw_mbs [pstr->raw_mbs_idx + byte_idx + i];
+	      buf[i] = pstr->mbs[byte_idx + i] = pstr->trans[ch];
+	    }
+	  p = (const char *) buf;
+	}
+      else
+	p = (const char *) pstr->raw_mbs + pstr->raw_mbs_idx + byte_idx;
+      mbclen = mbrtowc (&wc, p, remain_len, &pstr->cur_state);
+      if (BE (mbclen == (size_t) -2, 0))
+	{
+	  /* The buffer doesn't have enough space, finish to build.  */
+	  pstr->cur_state = prev_st;
+	  break;
+	}
+      else if (BE (mbclen == (size_t) -1 || mbclen == 0, 0))
+	{
+	  /* We treat these cases as a singlebyte character.  */
+	  mbclen = 1;
+	  wc = (wchar_t) pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx];
+	  if (BE (pstr->trans != NULL, 0))
+	    wc = pstr->trans[wc];
+	  pstr->cur_state = prev_st;
+	}
+
+      /* Write wide character and padding.  */
+      pstr->wcs[byte_idx++] = wc;
+      /* Write paddings.  */
+      for (remain_len = byte_idx + mbclen - 1; byte_idx < remain_len ;)
+	pstr->wcs[byte_idx++] = WEOF;
+    }
+  pstr->valid_len = byte_idx;
+  pstr->valid_raw_len = byte_idx;
+}
+
+/* Build wide character buffer PSTR->WCS like build_wcs_buffer,
+   but for REG_ICASE.  */
+
+static reg_errcode_t
+internal_function
+build_wcs_upper_buffer (re_string_t *pstr)
+{
+  mbstate_t prev_st;
+  int src_idx, byte_idx, end_idx, remain_len;
+  size_t mbclen;
+#ifdef _LIBC
+  char buf[MB_LEN_MAX];
+  assert (MB_LEN_MAX >= pstr->mb_cur_max);
+#else
+  char buf[64];
+#endif
+
+  byte_idx = pstr->valid_len;
+  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
+
+  /* The following optimization assumes that ASCII characters can be
+     mapped to wide characters with a simple cast.  */
+  if (! pstr->map_notascii && pstr->trans == NULL && !pstr->offsets_needed)
+    {
+      while (byte_idx < end_idx)
+	{
+	  wchar_t wc;
+
+	  if (isascii (pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx])
+	      && mbsinit (&pstr->cur_state))
+	    {
+	      /* In case of a singlebyte character.  */
+	      pstr->mbs[byte_idx]
+		= toupper (pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx]);
+	      /* The next step uses the assumption that wchar_t is encoded
+		 ASCII-safe: all ASCII values can be converted like this.  */
+	      pstr->wcs[byte_idx] = (wchar_t) pstr->mbs[byte_idx];
+	      ++byte_idx;
+	      continue;
+	    }
+
+	  remain_len = end_idx - byte_idx;
+	  prev_st = pstr->cur_state;
+	  mbclen = mbrtowc (&wc,
+			    ((const char *) pstr->raw_mbs + pstr->raw_mbs_idx
+			     + byte_idx), remain_len, &pstr->cur_state);
+	  if (BE (mbclen + 2 > 2, 1))
+	    {
+	      wchar_t wcu = wc;
+	      if (iswlower (wc))
+		{
+		  size_t mbcdlen;
+
+		  wcu = towupper (wc);
+		  mbcdlen = wcrtomb (buf, wcu, &prev_st);
+		  if (BE (mbclen == mbcdlen, 1))
+		    memcpy (pstr->mbs + byte_idx, buf, mbclen);
+		  else
+		    {
+		      src_idx = byte_idx;
+		      goto offsets_needed;
+		    }
+		}
+	      else
+		memcpy (pstr->mbs + byte_idx,
+			pstr->raw_mbs + pstr->raw_mbs_idx + byte_idx, mbclen);
+	      pstr->wcs[byte_idx++] = wcu;
+	      /* Write paddings.  */
+	      for (remain_len = byte_idx + mbclen - 1; byte_idx < remain_len ;)
+		pstr->wcs[byte_idx++] = WEOF;
+	    }
+	  else if (mbclen == (size_t) -1 || mbclen == 0)
+	    {
+	      /* It is an invalid character or '\0'.  Just use the byte.  */
+	      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + byte_idx];
+	      pstr->mbs[byte_idx] = ch;
+	      /* And also cast it to wide char.  */
+	      pstr->wcs[byte_idx++] = (wchar_t) ch;
+	      if (BE (mbclen == (size_t) -1, 0))
+		pstr->cur_state = prev_st;
+	    }
+	  else
+	    {
+	      /* The buffer doesn't have enough space, finish to build.  */
+	      pstr->cur_state = prev_st;
+	      break;
+	    }
+	}
+      pstr->valid_len = byte_idx;
+      pstr->valid_raw_len = byte_idx;
+      return REG_NOERROR;
+    }
+  else
+    for (src_idx = pstr->valid_raw_len; byte_idx < end_idx;)
+      {
+	wchar_t wc;
+	const char *p;
+      offsets_needed:
+	remain_len = end_idx - byte_idx;
+	prev_st = pstr->cur_state;
+	if (BE (pstr->trans != NULL, 0))
+	  {
+	    int i, ch;
+
+	    for (i = 0; i < pstr->mb_cur_max && i < remain_len; ++i)
+	      {
+		ch = pstr->raw_mbs [pstr->raw_mbs_idx + src_idx + i];
+		buf[i] = pstr->trans[ch];
+	      }
+	    p = (const char *) buf;
+	  }
+	else
+	  p = (const char *) pstr->raw_mbs + pstr->raw_mbs_idx + src_idx;
+	mbclen = mbrtowc (&wc, p, remain_len, &pstr->cur_state);
+	if (BE (mbclen + 2 > 2, 1))
+	  {
+	    wchar_t wcu = wc;
+	    if (iswlower (wc))
+	      {
+		size_t mbcdlen;
+
+		wcu = towupper (wc);
+		mbcdlen = wcrtomb ((char *) buf, wcu, &prev_st);
+		if (BE (mbclen == mbcdlen, 1))
+		  memcpy (pstr->mbs + byte_idx, buf, mbclen);
+		else if (mbcdlen != (size_t) -1)
+		  {
+		    size_t i;
+
+		    if (byte_idx + mbcdlen > pstr->bufs_len)
+		      {
+			pstr->cur_state = prev_st;
+			break;
+		      }
+
+		    if (pstr->offsets == NULL)
+		      {
+			pstr->offsets = re_malloc (int, pstr->bufs_len);
+
+			if (pstr->offsets == NULL)
+			  return REG_ESPACE;
+		      }
+		    if (!pstr->offsets_needed)
+		      {
+			for (i = 0; i < (size_t) byte_idx; ++i)
+			  pstr->offsets[i] = i;
+			pstr->offsets_needed = 1;
+		      }
+
+		    memcpy (pstr->mbs + byte_idx, buf, mbcdlen);
+		    pstr->wcs[byte_idx] = wcu;
+		    pstr->offsets[byte_idx] = src_idx;
+		    for (i = 1; i < mbcdlen; ++i)
+		      {
+			pstr->offsets[byte_idx + i]
+			  = src_idx + (i < mbclen ? i : mbclen - 1);
+			pstr->wcs[byte_idx + i] = WEOF;
+		      }
+		    pstr->len += mbcdlen - mbclen;
+		    if (pstr->raw_stop > src_idx)
+		      pstr->stop += mbcdlen - mbclen;
+		    end_idx = (pstr->bufs_len > pstr->len)
+			      ? pstr->len : pstr->bufs_len;
+		    byte_idx += mbcdlen;
+		    src_idx += mbclen;
+		    continue;
+		  }
+                else
+                  memcpy (pstr->mbs + byte_idx, p, mbclen);
+	      }
+	    else
+	      memcpy (pstr->mbs + byte_idx, p, mbclen);
+
+	    if (BE (pstr->offsets_needed != 0, 0))
+	      {
+		size_t i;
+		for (i = 0; i < mbclen; ++i)
+		  pstr->offsets[byte_idx + i] = src_idx + i;
+	      }
+	    src_idx += mbclen;
+
+	    pstr->wcs[byte_idx++] = wcu;
+	    /* Write paddings.  */
+	    for (remain_len = byte_idx + mbclen - 1; byte_idx < remain_len ;)
+	      pstr->wcs[byte_idx++] = WEOF;
+	  }
+	else if (mbclen == (size_t) -1 || mbclen == 0)
+	  {
+	    /* It is an invalid character or '\0'.  Just use the byte.  */
+	    int ch = pstr->raw_mbs[pstr->raw_mbs_idx + src_idx];
+
+	    if (BE (pstr->trans != NULL, 0))
+	      ch = pstr->trans [ch];
+	    pstr->mbs[byte_idx] = ch;
+
+	    if (BE (pstr->offsets_needed != 0, 0))
+	      pstr->offsets[byte_idx] = src_idx;
+	    ++src_idx;
+
+	    /* And also cast it to wide char.  */
+	    pstr->wcs[byte_idx++] = (wchar_t) ch;
+	    if (BE (mbclen == (size_t) -1, 0))
+	      pstr->cur_state = prev_st;
+	  }
+	else
+	  {
+	    /* The buffer doesn't have enough space, finish to build.  */
+	    pstr->cur_state = prev_st;
+	    break;
+	  }
+      }
+  pstr->valid_len = byte_idx;
+  pstr->valid_raw_len = src_idx;
+  return REG_NOERROR;
+}
+
+/* Skip characters until the index becomes greater than NEW_RAW_IDX.
+   Return the index.  */
+
+static int
+internal_function
+re_string_skip_chars (re_string_t *pstr, int new_raw_idx, wint_t *last_wc)
+{
+  mbstate_t prev_st;
+  int rawbuf_idx;
+  size_t mbclen;
+  wchar_t wc = WEOF;
+
+  /* Skip the characters which are not necessary to check.  */
+  for (rawbuf_idx = pstr->raw_mbs_idx + pstr->valid_raw_len;
+       rawbuf_idx < new_raw_idx;)
+    {
+      int remain_len;
+      remain_len = pstr->len - rawbuf_idx;
+      prev_st = pstr->cur_state;
+      mbclen = mbrtowc (&wc, (const char *) pstr->raw_mbs + rawbuf_idx,
+			remain_len, &pstr->cur_state);
+      if (BE (mbclen == (size_t) -2 || mbclen == (size_t) -1 || mbclen == 0, 0))
+	{
+	  /* We treat these cases as a single byte character.  */
+	  if (mbclen == 0 || remain_len == 0)
+	    wc = L'\0';
+	  else
+	    wc = *(unsigned char *) (pstr->raw_mbs + rawbuf_idx);
+	  mbclen = 1;
+	  pstr->cur_state = prev_st;
+	}
+      /* Then proceed the next character.  */
+      rawbuf_idx += mbclen;
+    }
+  *last_wc = (wint_t) wc;
+  return rawbuf_idx;
+}
+#endif /* RE_ENABLE_I18N  */
+
+/* Build the buffer PSTR->MBS, and apply the translation if we need.
+   This function is used in case of REG_ICASE.  */
+
+static void
+internal_function
+build_upper_buffer (re_string_t *pstr)
+{
+  int char_idx, end_idx;
+  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
+
+  for (char_idx = pstr->valid_len; char_idx < end_idx; ++char_idx)
+    {
+      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + char_idx];
+      if (BE (pstr->trans != NULL, 0))
+	ch = pstr->trans[ch];
+      if (islower (ch))
+	pstr->mbs[char_idx] = toupper (ch);
+      else
+	pstr->mbs[char_idx] = ch;
+    }
+  pstr->valid_len = char_idx;
+  pstr->valid_raw_len = char_idx;
+}
+
+/* Apply TRANS to the buffer in PSTR.  */
+
+static void
+internal_function
+re_string_translate_buffer (re_string_t *pstr)
+{
+  int buf_idx, end_idx;
+  end_idx = (pstr->bufs_len > pstr->len) ? pstr->len : pstr->bufs_len;
+
+  for (buf_idx = pstr->valid_len; buf_idx < end_idx; ++buf_idx)
+    {
+      int ch = pstr->raw_mbs[pstr->raw_mbs_idx + buf_idx];
+      pstr->mbs[buf_idx] = pstr->trans[ch];
+    }
+
+  pstr->valid_len = buf_idx;
+  pstr->valid_raw_len = buf_idx;
+}
+
+/* This function re-construct the buffers.
+   Concretely, convert to wide character in case of pstr->mb_cur_max > 1,
+   convert to upper case in case of REG_ICASE, apply translation.  */
+
+static reg_errcode_t
+internal_function
+re_string_reconstruct (re_string_t *pstr, int idx, int eflags)
+{
+  int offset = idx - pstr->raw_mbs_idx;
+  if (BE (offset < 0, 0))
+    {
+      /* Reset buffer.  */
+#ifdef RE_ENABLE_I18N
+      if (pstr->mb_cur_max > 1)
+	memset (&pstr->cur_state, '\0', sizeof (mbstate_t));
+#endif /* RE_ENABLE_I18N */
+      pstr->len = pstr->raw_len;
+      pstr->stop = pstr->raw_stop;
+      pstr->valid_len = 0;
+      pstr->raw_mbs_idx = 0;
+      pstr->valid_raw_len = 0;
+      pstr->offsets_needed = 0;
+      pstr->tip_context = ((eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
+			   : CONTEXT_NEWLINE | CONTEXT_BEGBUF);
+      if (!pstr->mbs_allocated)
+	pstr->mbs = (unsigned char *) pstr->raw_mbs;
+      offset = idx;
+    }
+
+  if (BE (offset != 0, 1))
+    {
+      /* Should the already checked characters be kept?  */
+      if (BE (offset < pstr->valid_raw_len, 1))
+	{
+	  /* Yes, move them to the front of the buffer.  */
+#ifdef RE_ENABLE_I18N
+	  if (BE (pstr->offsets_needed, 0))
+	    {
+	      int low = 0, high = pstr->valid_len, mid;
+	      do
+		{
+		  mid = (high + low) / 2;
+		  if (pstr->offsets[mid] > offset)
+		    high = mid;
+		  else if (pstr->offsets[mid] < offset)
+		    low = mid + 1;
+		  else
+		    break;
+		}
+	      while (low < high);
+	      if (pstr->offsets[mid] < offset)
+		++mid;
+	      pstr->tip_context = re_string_context_at (pstr, mid - 1,
+							eflags);
+	      /* This can be quite complicated, so handle specially
+		 only the common and easy case where the character with
+		 different length representation of lower and upper
+		 case is present at or after offset.  */
+	      if (pstr->valid_len > offset
+		  && mid == offset && pstr->offsets[mid] == offset)
+		{
+		  memmove (pstr->wcs, pstr->wcs + offset,
+			   (pstr->valid_len - offset) * sizeof (wint_t));
+		  memmove (pstr->mbs, pstr->mbs + offset, pstr->valid_len - offset);
+		  pstr->valid_len -= offset;
+		  pstr->valid_raw_len -= offset;
+		  for (low = 0; low < pstr->valid_len; low++)
+		    pstr->offsets[low] = pstr->offsets[low + offset] - offset;
+		}
+	      else
+		{
+		  /* Otherwise, just find out how long the partial multibyte
+		     character at offset is and fill it with WEOF/255.  */
+		  pstr->len = pstr->raw_len - idx + offset;
+		  pstr->stop = pstr->raw_stop - idx + offset;
+		  pstr->offsets_needed = 0;
+		  while (mid > 0 && pstr->offsets[mid - 1] == offset)
+		    --mid;
+		  while (mid < pstr->valid_len)
+		    if (pstr->wcs[mid] != WEOF)
+		      break;
+		    else
+		      ++mid;
+		  if (mid == pstr->valid_len)
+		    pstr->valid_len = 0;
+		  else
+		    {
+		      pstr->valid_len = pstr->offsets[mid] - offset;
+		      if (pstr->valid_len)
+			{
+			  for (low = 0; low < pstr->valid_len; ++low)
+			    pstr->wcs[low] = WEOF;
+			  memset (pstr->mbs, 255, pstr->valid_len);
+			}
+		    }
+		  pstr->valid_raw_len = pstr->valid_len;
+		}
+	    }
+	  else
+#endif
+	    {
+	      pstr->tip_context = re_string_context_at (pstr, offset - 1,
+							eflags);
+#ifdef RE_ENABLE_I18N
+	      if (pstr->mb_cur_max > 1)
+		memmove (pstr->wcs, pstr->wcs + offset,
+			 (pstr->valid_len - offset) * sizeof (wint_t));
+#endif /* RE_ENABLE_I18N */
+	      if (BE (pstr->mbs_allocated, 0))
+		memmove (pstr->mbs, pstr->mbs + offset,
+			 pstr->valid_len - offset);
+	      pstr->valid_len -= offset;
+	      pstr->valid_raw_len -= offset;
+#if DEBUG
+	      assert (pstr->valid_len > 0);
+#endif
+	    }
+	}
+      else
+	{
+	  /* No, skip all characters until IDX.  */
+	  int prev_valid_len = pstr->valid_len;
+
+#ifdef RE_ENABLE_I18N
+	  if (BE (pstr->offsets_needed, 0))
+	    {
+	      pstr->len = pstr->raw_len - idx + offset;
+	      pstr->stop = pstr->raw_stop - idx + offset;
+	      pstr->offsets_needed = 0;
+	    }
+#endif
+	  pstr->valid_len = 0;
+#ifdef RE_ENABLE_I18N
+	  if (pstr->mb_cur_max > 1)
+	    {
+	      int wcs_idx;
+	      wint_t wc = WEOF;
+
+	      if (pstr->is_utf8)
+		{
+		  const unsigned char *raw, *p, *q, *end;
+
+		  /* Special case UTF-8.  Multi-byte chars start with any
+		     byte other than 0x80 - 0xbf.  */
+		  raw = pstr->raw_mbs + pstr->raw_mbs_idx;
+		  end = raw + (offset - pstr->mb_cur_max);
+		  if (end < pstr->raw_mbs)
+		    end = pstr->raw_mbs;
+		  p = raw + offset - 1;
+#ifdef _LIBC
+		  /* We know the wchar_t encoding is UCS4, so for the simple
+		     case, ASCII characters, skip the conversion step.  */
+		  if (isascii (*p) && BE (pstr->trans == NULL, 1))
+		    {
+		      memset (&pstr->cur_state, '\0', sizeof (mbstate_t));
+		      /* pstr->valid_len = 0; */
+		      wc = (wchar_t) *p;
+		    }
+		  else
+#endif
+		    for (; p >= end; --p)
+		      if ((*p & 0xc0) != 0x80)
+			{
+			  mbstate_t cur_state;
+			  wchar_t wc2;
+			  int mlen = raw + pstr->len - p;
+			  unsigned char buf[6];
+			  size_t mbclen;
+
+			  q = p;
+			  if (BE (pstr->trans != NULL, 0))
+			    {
+			      int i = mlen < 6 ? mlen : 6;
+			      while (--i >= 0)
+				buf[i] = pstr->trans[p[i]];
+			      q = buf;
+			    }
+			  /* XXX Don't use mbrtowc, we know which conversion
+			     to use (UTF-8 -> UCS4).  */
+			  memset (&cur_state, 0, sizeof (cur_state));
+			  mbclen = mbrtowc (&wc2, (const char *) p, mlen,
+					    &cur_state);
+			  if (raw + offset - p <= mbclen
+			      && mbclen < (size_t) -2)
+			    {
+			      memset (&pstr->cur_state, '\0',
+				      sizeof (mbstate_t));
+			      pstr->valid_len = mbclen - (raw + offset - p);
+			      wc = wc2;
+			    }
+			  break;
+			}
+		}
+
+	      if (wc == WEOF)
+		pstr->valid_len = re_string_skip_chars (pstr, idx, &wc) - idx;
+	      if (wc == WEOF)
+		pstr->tip_context
+		  = re_string_context_at (pstr, prev_valid_len - 1, eflags);
+	      else
+		pstr->tip_context = ((BE (pstr->word_ops_used != 0, 0)
+				      && IS_WIDE_WORD_CHAR (wc))
+				     ? CONTEXT_WORD
+				     : ((IS_WIDE_NEWLINE (wc)
+					 && pstr->newline_anchor)
+					? CONTEXT_NEWLINE : 0));
+	      if (BE (pstr->valid_len, 0))
+		{
+		  for (wcs_idx = 0; wcs_idx < pstr->valid_len; ++wcs_idx)
+		    pstr->wcs[wcs_idx] = WEOF;
+		  if (pstr->mbs_allocated)
+		    memset (pstr->mbs, 255, pstr->valid_len);
+		}
+	      pstr->valid_raw_len = pstr->valid_len;
+	    }
+	  else
+#endif /* RE_ENABLE_I18N */
+	    {
+	      int c = pstr->raw_mbs[pstr->raw_mbs_idx + offset - 1];
+	      pstr->valid_raw_len = 0;
+	      if (pstr->trans)
+		c = pstr->trans[c];
+	      pstr->tip_context = (bitset_contain (pstr->word_char, c)
+				   ? CONTEXT_WORD
+				   : ((IS_NEWLINE (c) && pstr->newline_anchor)
+				      ? CONTEXT_NEWLINE : 0));
+	    }
+	}
+      if (!BE (pstr->mbs_allocated, 0))
+	pstr->mbs += offset;
+    }
+  pstr->raw_mbs_idx = idx;
+  pstr->len -= offset;
+  pstr->stop -= offset;
+
+  /* Then build the buffers.  */
+#ifdef RE_ENABLE_I18N
+  if (pstr->mb_cur_max > 1)
+    {
+      if (pstr->icase)
+	{
+	  reg_errcode_t ret = build_wcs_upper_buffer (pstr);
+	  if (BE (ret != REG_NOERROR, 0))
+	    return ret;
+	}
+      else
+	build_wcs_buffer (pstr);
+    }
+  else
+#endif /* RE_ENABLE_I18N */
+    if (BE (pstr->mbs_allocated, 0))
+      {
+	if (pstr->icase)
+	  build_upper_buffer (pstr);
+	else if (pstr->trans != NULL)
+	  re_string_translate_buffer (pstr);
+      }
+    else
+      pstr->valid_len = pstr->len;
+
+  pstr->cur_idx = 0;
+  return REG_NOERROR;
+}
+
+static unsigned char
+internal_function __attribute ((pure))
+re_string_peek_byte_case (const re_string_t *pstr, int idx)
+{
+  int ch, off;
+
+  /* Handle the common (easiest) cases first.  */
+  if (BE (!pstr->mbs_allocated, 1))
+    return re_string_peek_byte (pstr, idx);
+
+#ifdef RE_ENABLE_I18N
+  if (pstr->mb_cur_max > 1
+      && ! re_string_is_single_byte_char (pstr, pstr->cur_idx + idx))
+    return re_string_peek_byte (pstr, idx);
+#endif
+
+  off = pstr->cur_idx + idx;
+#ifdef RE_ENABLE_I18N
+  if (pstr->offsets_needed)
+    off = pstr->offsets[off];
+#endif
+
+  ch = pstr->raw_mbs[pstr->raw_mbs_idx + off];
+
+#ifdef RE_ENABLE_I18N
+  /* Ensure that e.g. for tr_TR.UTF-8 BACKSLASH DOTLESS SMALL LETTER I
+     this function returns CAPITAL LETTER I instead of first byte of
+     DOTLESS SMALL LETTER I.  The latter would confuse the parser,
+     since peek_byte_case doesn't advance cur_idx in any way.  */
+  if (pstr->offsets_needed && !isascii (ch))
+    return re_string_peek_byte (pstr, idx);
+#endif
+
+  return ch;
+}
+
+static unsigned char
+internal_function __attribute ((pure))
+re_string_fetch_byte_case (re_string_t *pstr)
+{
+  if (BE (!pstr->mbs_allocated, 1))
+    return re_string_fetch_byte (pstr);
+
+#ifdef RE_ENABLE_I18N
+  if (pstr->offsets_needed)
+    {
+      int off, ch;
+
+      /* For tr_TR.UTF-8 [[:islower:]] there is
+	 [[: CAPITAL LETTER I WITH DOT lower:]] in mbs.  Skip
+	 in that case the whole multi-byte character and return
+	 the original letter.  On the other side, with
+	 [[: DOTLESS SMALL LETTER I return [[:I, as doing
+	 anything else would complicate things too much.  */
+
+      if (!re_string_first_byte (pstr, pstr->cur_idx))
+	return re_string_fetch_byte (pstr);
+
+      off = pstr->offsets[pstr->cur_idx];
+      ch = pstr->raw_mbs[pstr->raw_mbs_idx + off];
+
+      if (! isascii (ch))
+	return re_string_fetch_byte (pstr);
+
+      re_string_skip_bytes (pstr,
+			    re_string_char_size_at (pstr, pstr->cur_idx));
+      return ch;
+    }
+#endif
+
+  return pstr->raw_mbs[pstr->raw_mbs_idx + pstr->cur_idx++];
+}
+
+static void
+internal_function
+re_string_destruct (re_string_t *pstr)
+{
+#ifdef RE_ENABLE_I18N
+  re_free (pstr->wcs);
+  re_free (pstr->offsets);
+#endif /* RE_ENABLE_I18N  */
+  if (pstr->mbs_allocated)
+    re_free (pstr->mbs);
+}
+
+/* Return the context at IDX in INPUT.  */
+
+static unsigned int
+internal_function
+re_string_context_at (const re_string_t *input, int idx, int eflags)
+{
+  int c;
+  if (BE (idx < 0, 0))
+    /* In this case, we use the value stored in input->tip_context,
+       since we can't know the character in input->mbs[-1] here.  */
+    return input->tip_context;
+  if (BE (idx == input->len, 0))
+    return ((eflags & REG_NOTEOL) ? CONTEXT_ENDBUF
+	    : CONTEXT_NEWLINE | CONTEXT_ENDBUF);
+#ifdef RE_ENABLE_I18N
+  if (input->mb_cur_max > 1)
+    {
+      wint_t wc;
+      int wc_idx = idx;
+      while(input->wcs[wc_idx] == WEOF)
+	{
+#ifdef DEBUG
+	  /* It must not happen.  */
+	  assert (wc_idx >= 0);
+#endif
+	  --wc_idx;
+	  if (wc_idx < 0)
+	    return input->tip_context;
+	}
+      wc = input->wcs[wc_idx];
+      if (BE (input->word_ops_used != 0, 0) && IS_WIDE_WORD_CHAR (wc))
+	return CONTEXT_WORD;
+      return (IS_WIDE_NEWLINE (wc) && input->newline_anchor
+	      ? CONTEXT_NEWLINE : 0);
+    }
+  else
+#endif
+    {
+      c = re_string_byte_at (input, idx);
+      if (bitset_contain (input->word_char, c))
+	return CONTEXT_WORD;
+      return IS_NEWLINE (c) && input->newline_anchor ? CONTEXT_NEWLINE : 0;
+    }
+}
+
+/* Functions for set operation.  */
+
+static reg_errcode_t
+internal_function
+re_node_set_alloc (re_node_set *set, int size)
+{
+  set->alloc = size;
+  set->nelem = 0;
+  set->elems = re_malloc (int, size);
+  if (BE (set->elems == NULL, 0))
+    return REG_ESPACE;
+  return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+re_node_set_init_1 (re_node_set *set, int elem)
+{
+  set->alloc = 1;
+  set->nelem = 1;
+  set->elems = re_malloc (int, 1);
+  if (BE (set->elems == NULL, 0))
+    {
+      set->alloc = set->nelem = 0;
+      return REG_ESPACE;
+    }
+  set->elems[0] = elem;
+  return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+re_node_set_init_2 (re_node_set *set, int elem1, int elem2)
+{
+  set->alloc = 2;
+  set->elems = re_malloc (int, 2);
+  if (BE (set->elems == NULL, 0))
+    return REG_ESPACE;
+  if (elem1 == elem2)
+    {
+      set->nelem = 1;
+      set->elems[0] = elem1;
+    }
+  else
+    {
+      set->nelem = 2;
+      if (elem1 < elem2)
+	{
+	  set->elems[0] = elem1;
+	  set->elems[1] = elem2;
+	}
+      else
+	{
+	  set->elems[0] = elem2;
+	  set->elems[1] = elem1;
+	}
+    }
+  return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+re_node_set_init_copy (re_node_set *dest, const re_node_set *src)
+{
+  dest->nelem = src->nelem;
+  if (src->nelem > 0)
+    {
+      dest->alloc = dest->nelem;
+      dest->elems = re_malloc (int, dest->alloc);
+      if (BE (dest->elems == NULL, 0))
+	{
+	  dest->alloc = dest->nelem = 0;
+	  return REG_ESPACE;
+	}
+      memcpy (dest->elems, src->elems, src->nelem * sizeof (int));
+    }
+  else
+    re_node_set_init_empty (dest);
+  return REG_NOERROR;
+}
+
+/* Calculate the intersection of the sets SRC1 and SRC2. And merge it to
+   DEST. Return value indicate the error code or REG_NOERROR if succeeded.
+   Note: We assume dest->elems is NULL, when dest->alloc is 0.  */
+
+static reg_errcode_t
+internal_function
+re_node_set_add_intersect (re_node_set *dest, const re_node_set *src1,
+			   const re_node_set *src2)
+{
+  int i1, i2, is, id, delta, sbase;
+  if (src1->nelem == 0 || src2->nelem == 0)
+    return REG_NOERROR;
+
+  /* We need dest->nelem + 2 * elems_in_intersection; this is a
+     conservative estimate.  */
+  if (src1->nelem + src2->nelem + dest->nelem > dest->alloc)
+    {
+      int new_alloc = src1->nelem + src2->nelem + dest->alloc;
+      int *new_elems = re_realloc (dest->elems, int, new_alloc);
+      if (BE (new_elems == NULL, 0))
+        return REG_ESPACE;
+      dest->elems = new_elems;
+      dest->alloc = new_alloc;
+    }
+
+  /* Find the items in the intersection of SRC1 and SRC2, and copy
+     into the top of DEST those that are not already in DEST itself.  */
+  sbase = dest->nelem + src1->nelem + src2->nelem;
+  i1 = src1->nelem - 1;
+  i2 = src2->nelem - 1;
+  id = dest->nelem - 1;
+  for (;;)
+    {
+      if (src1->elems[i1] == src2->elems[i2])
+	{
+	  /* Try to find the item in DEST.  Maybe we could binary search?  */
+	  while (id >= 0 && dest->elems[id] > src1->elems[i1])
+	    --id;
+
+          if (id < 0 || dest->elems[id] != src1->elems[i1])
+            dest->elems[--sbase] = src1->elems[i1];
+
+	  if (--i1 < 0 || --i2 < 0)
+	    break;
+	}
+
+      /* Lower the highest of the two items.  */
+      else if (src1->elems[i1] < src2->elems[i2])
+	{
+	  if (--i2 < 0)
+	    break;
+	}
+      else
+	{
+	  if (--i1 < 0)
+	    break;
+	}
+    }
+
+  id = dest->nelem - 1;
+  is = dest->nelem + src1->nelem + src2->nelem - 1;
+  delta = is - sbase + 1;
+
+  /* Now copy.  When DELTA becomes zero, the remaining
+     DEST elements are already in place; this is more or
+     less the same loop that is in re_node_set_merge.  */
+  dest->nelem += delta;
+  if (delta > 0 && id >= 0)
+    for (;;)
+      {
+        if (dest->elems[is] > dest->elems[id])
+          {
+            /* Copy from the top.  */
+            dest->elems[id + delta--] = dest->elems[is--];
+            if (delta == 0)
+              break;
+          }
+        else
+          {
+            /* Slide from the bottom.  */
+            dest->elems[id + delta] = dest->elems[id];
+            if (--id < 0)
+              break;
+          }
+      }
+
+  /* Copy remaining SRC elements.  */
+  memcpy (dest->elems, dest->elems + sbase, delta * sizeof (int));
+
+  return REG_NOERROR;
+}
+
+/* Calculate the union set of the sets SRC1 and SRC2. And store it to
+   DEST. Return value indicate the error code or REG_NOERROR if succeeded.  */
+
+static reg_errcode_t
+internal_function
+re_node_set_init_union (re_node_set *dest, const re_node_set *src1,
+			const re_node_set *src2)
+{
+  int i1, i2, id;
+  if (src1 != NULL && src1->nelem > 0 && src2 != NULL && src2->nelem > 0)
+    {
+      dest->alloc = src1->nelem + src2->nelem;
+      dest->elems = re_malloc (int, dest->alloc);
+      if (BE (dest->elems == NULL, 0))
+	return REG_ESPACE;
+    }
+  else
+    {
+      if (src1 != NULL && src1->nelem > 0)
+	return re_node_set_init_copy (dest, src1);
+      else if (src2 != NULL && src2->nelem > 0)
+	return re_node_set_init_copy (dest, src2);
+      else
+	re_node_set_init_empty (dest);
+      return REG_NOERROR;
+    }
+  for (i1 = i2 = id = 0 ; i1 < src1->nelem && i2 < src2->nelem ;)
+    {
+      if (src1->elems[i1] > src2->elems[i2])
+	{
+	  dest->elems[id++] = src2->elems[i2++];
+	  continue;
+	}
+      if (src1->elems[i1] == src2->elems[i2])
+	++i2;
+      dest->elems[id++] = src1->elems[i1++];
+    }
+  if (i1 < src1->nelem)
+    {
+      memcpy (dest->elems + id, src1->elems + i1,
+	     (src1->nelem - i1) * sizeof (int));
+      id += src1->nelem - i1;
+    }
+  else if (i2 < src2->nelem)
+    {
+      memcpy (dest->elems + id, src2->elems + i2,
+	     (src2->nelem - i2) * sizeof (int));
+      id += src2->nelem - i2;
+    }
+  dest->nelem = id;
+  return REG_NOERROR;
+}
+
+/* Calculate the union set of the sets DEST and SRC. And store it to
+   DEST. Return value indicate the error code or REG_NOERROR if succeeded.  */
+
+static reg_errcode_t
+internal_function
+re_node_set_merge (re_node_set *dest, const re_node_set *src)
+{
+  int is, id, sbase, delta;
+  if (src == NULL || src->nelem == 0)
+    return REG_NOERROR;
+  if (dest->alloc < 2 * src->nelem + dest->nelem)
+    {
+      int new_alloc = 2 * (src->nelem + dest->alloc);
+      int *new_buffer = re_realloc (dest->elems, int, new_alloc);
+      if (BE (new_buffer == NULL, 0))
+	return REG_ESPACE;
+      dest->elems = new_buffer;
+      dest->alloc = new_alloc;
+    }
+
+  if (BE (dest->nelem == 0, 0))
+    {
+      dest->nelem = src->nelem;
+      memcpy (dest->elems, src->elems, src->nelem * sizeof (int));
+      return REG_NOERROR;
+    }
+
+  /* Copy into the top of DEST the items of SRC that are not
+     found in DEST.  Maybe we could binary search in DEST?  */
+  for (sbase = dest->nelem + 2 * src->nelem,
+       is = src->nelem - 1, id = dest->nelem - 1; is >= 0 && id >= 0; )
+    {
+      if (dest->elems[id] == src->elems[is])
+        is--, id--;
+      else if (dest->elems[id] < src->elems[is])
+        dest->elems[--sbase] = src->elems[is--];
+      else /* if (dest->elems[id] > src->elems[is]) */
+        --id;
+    }
+
+  if (is >= 0)
+    {
+      /* If DEST is exhausted, the remaining items of SRC must be unique.  */
+      sbase -= is + 1;
+      memcpy (dest->elems + sbase, src->elems, (is + 1) * sizeof (int));
+    }
+
+  id = dest->nelem - 1;
+  is = dest->nelem + 2 * src->nelem - 1;
+  delta = is - sbase + 1;
+  if (delta == 0)
+    return REG_NOERROR;
+
+  /* Now copy.  When DELTA becomes zero, the remaining
+     DEST elements are already in place.  */
+  dest->nelem += delta;
+  for (;;)
+    {
+      if (dest->elems[is] > dest->elems[id])
+        {
+	  /* Copy from the top.  */
+          dest->elems[id + delta--] = dest->elems[is--];
+	  if (delta == 0)
+	    break;
+	}
+      else
+        {
+          /* Slide from the bottom.  */
+          dest->elems[id + delta] = dest->elems[id];
+	  if (--id < 0)
+	    {
+	      /* Copy remaining SRC elements.  */
+	      memcpy (dest->elems, dest->elems + sbase,
+	              delta * sizeof (int));
+	      break;
+	    }
+	}
+    }
+
+  return REG_NOERROR;
+}
+
+/* Insert the new element ELEM to the re_node_set* SET.
+   SET should not already have ELEM.
+   return -1 if an error is occured, return 1 otherwise.  */
+
+static int
+internal_function
+re_node_set_insert (re_node_set *set, int elem)
+{
+  int idx;
+  /* In case the set is empty.  */
+  if (set->alloc == 0)
+    {
+      if (BE (re_node_set_init_1 (set, elem) == REG_NOERROR, 1))
+	return 1;
+      else
+	return -1;
+    }
+
+  if (BE (set->nelem, 0) == 0)
+    {
+      /* We already guaranteed above that set->alloc != 0.  */
+      set->elems[0] = elem;
+      ++set->nelem;
+      return 1;
+    }
+
+  /* Realloc if we need.  */
+  if (set->alloc == set->nelem)
+    {
+      int *new_elems;
+      set->alloc = set->alloc * 2;
+      new_elems = re_realloc (set->elems, int, set->alloc);
+      if (BE (new_elems == NULL, 0))
+	return -1;
+      set->elems = new_elems;
+    }
+
+  /* Move the elements which follows the new element.  Test the
+     first element separately to skip a check in the inner loop.  */
+  if (elem < set->elems[0])
+    {
+      idx = 0;
+      for (idx = set->nelem; idx > 0; idx--)
+        set->elems[idx] = set->elems[idx - 1];
+    }
+  else
+    {
+      for (idx = set->nelem; set->elems[idx - 1] > elem; idx--)
+        set->elems[idx] = set->elems[idx - 1];
+    }
+
+  /* Insert the new element.  */
+  set->elems[idx] = elem;
+  ++set->nelem;
+  return 1;
+}
+
+/* Insert the new element ELEM to the re_node_set* SET.
+   SET should not already have any element greater than or equal to ELEM.
+   Return -1 if an error is occured, return 1 otherwise.  */
+
+static int
+internal_function
+re_node_set_insert_last (re_node_set *set, int elem)
+{
+  /* Realloc if we need.  */
+  if (set->alloc == set->nelem)
+    {
+      int *new_elems;
+      set->alloc = (set->alloc + 1) * 2;
+      new_elems = re_realloc (set->elems, int, set->alloc);
+      if (BE (new_elems == NULL, 0))
+	return -1;
+      set->elems = new_elems;
+    }
+
+  /* Insert the new element.  */
+  set->elems[set->nelem++] = elem;
+  return 1;
+}
+
+/* Compare two node sets SET1 and SET2.
+   return 1 if SET1 and SET2 are equivalent, return 0 otherwise.  */
+
+static int
+internal_function __attribute ((pure))
+re_node_set_compare (const re_node_set *set1, const re_node_set *set2)
+{
+  int i;
+  if (set1 == NULL || set2 == NULL || set1->nelem != set2->nelem)
+    return 0;
+  for (i = set1->nelem ; --i >= 0 ; )
+    if (set1->elems[i] != set2->elems[i])
+      return 0;
+  return 1;
+}
+
+/* Return (idx + 1) if SET contains the element ELEM, return 0 otherwise.  */
+
+static int
+internal_function __attribute ((pure))
+re_node_set_contains (const re_node_set *set, int elem)
+{
+  unsigned int idx, right, mid;
+  if (set->nelem <= 0)
+    return 0;
+
+  /* Binary search the element.  */
+  idx = 0;
+  right = set->nelem - 1;
+  while (idx < right)
+    {
+      mid = (idx + right) / 2;
+      if (set->elems[mid] < elem)
+	idx = mid + 1;
+      else
+	right = mid;
+    }
+  return set->elems[idx] == elem ? idx + 1 : 0;
+}
+
+static void
+internal_function
+re_node_set_remove_at (re_node_set *set, int idx)
+{
+  if (idx < 0 || idx >= set->nelem)
+    return;
+  --set->nelem;
+  for (; idx < set->nelem; idx++)
+    set->elems[idx] = set->elems[idx + 1];
+}
+
+
+/* Add the token TOKEN to dfa->nodes, and return the index of the token.
+   Or return -1, if an error will be occured.  */
+
+static int
+internal_function
+re_dfa_add_node (re_dfa_t *dfa, re_token_t token)
+{
+  int type = token.type;
+  if (BE (dfa->nodes_len >= dfa->nodes_alloc, 0))
+    {
+      size_t new_nodes_alloc = dfa->nodes_alloc * 2;
+      int *new_nexts, *new_indices;
+      re_node_set *new_edests, *new_eclosures;
+      re_token_t *new_nodes;
+
+      /* Avoid overflows.  */
+      if (BE (new_nodes_alloc < dfa->nodes_alloc, 0))
+	return -1;
+
+      new_nodes = re_realloc (dfa->nodes, re_token_t, new_nodes_alloc);
+      if (BE (new_nodes == NULL, 0))
+	return -1;
+      dfa->nodes = new_nodes;
+      new_nexts = re_realloc (dfa->nexts, int, new_nodes_alloc);
+      new_indices = re_realloc (dfa->org_indices, int, new_nodes_alloc);
+      new_edests = re_realloc (dfa->edests, re_node_set, new_nodes_alloc);
+      new_eclosures = re_realloc (dfa->eclosures, re_node_set, new_nodes_alloc);
+      if (BE (new_nexts == NULL || new_indices == NULL
+	      || new_edests == NULL || new_eclosures == NULL, 0))
+	return -1;
+      dfa->nexts = new_nexts;
+      dfa->org_indices = new_indices;
+      dfa->edests = new_edests;
+      dfa->eclosures = new_eclosures;
+      dfa->nodes_alloc = new_nodes_alloc;
+    }
+  dfa->nodes[dfa->nodes_len] = token;
+  dfa->nodes[dfa->nodes_len].constraint = 0;
+#ifdef RE_ENABLE_I18N
+  dfa->nodes[dfa->nodes_len].accept_mb =
+    (type == OP_PERIOD && dfa->mb_cur_max > 1) || type == COMPLEX_BRACKET;
+#endif
+  dfa->nexts[dfa->nodes_len] = -1;
+  re_node_set_init_empty (dfa->edests + dfa->nodes_len);
+  re_node_set_init_empty (dfa->eclosures + dfa->nodes_len);
+  return dfa->nodes_len++;
+}
+
+static inline unsigned int
+internal_function
+calc_state_hash (const re_node_set *nodes, unsigned int context)
+{
+  unsigned int hash = nodes->nelem + context;
+  int i;
+  for (i = 0 ; i < nodes->nelem ; i++)
+    hash += nodes->elems[i];
+  return hash;
+}
+
+/* Search for the state whose node_set is equivalent to NODES.
+   Return the pointer to the state, if we found it in the DFA.
+   Otherwise create the new one and return it.  In case of an error
+   return NULL and set the error code in ERR.
+   Note: - We assume NULL as the invalid state, then it is possible that
+	   return value is NULL and ERR is REG_NOERROR.
+	 - We never return non-NULL value in case of any errors, it is for
+	   optimization.  */
+
+static re_dfastate_t *
+internal_function
+re_acquire_state (reg_errcode_t *err, const re_dfa_t *dfa,
+		  const re_node_set *nodes)
+{
+  unsigned int hash;
+  re_dfastate_t *new_state;
+  struct re_state_table_entry *spot;
+  int i;
+  if (BE (nodes->nelem == 0, 0))
+    {
+      *err = REG_NOERROR;
+      return NULL;
+    }
+  hash = calc_state_hash (nodes, 0);
+  spot = dfa->state_table + (hash & dfa->state_hash_mask);
+
+  for (i = 0 ; i < spot->num ; i++)
+    {
+      re_dfastate_t *state = spot->array[i];
+      if (hash != state->hash)
+	continue;
+      if (re_node_set_compare (&state->nodes, nodes))
+	return state;
+    }
+
+  /* There are no appropriate state in the dfa, create the new one.  */
+  new_state = create_ci_newstate (dfa, nodes, hash);
+  if (BE (new_state == NULL, 0))
+    *err = REG_ESPACE;
+
+  return new_state;
+}
+
+/* Search for the state whose node_set is equivalent to NODES and
+   whose context is equivalent to CONTEXT.
+   Return the pointer to the state, if we found it in the DFA.
+   Otherwise create the new one and return it.  In case of an error
+   return NULL and set the error code in ERR.
+   Note: - We assume NULL as the invalid state, then it is possible that
+	   return value is NULL and ERR is REG_NOERROR.
+	 - We never return non-NULL value in case of any errors, it is for
+	   optimization.  */
+
+static re_dfastate_t *
+internal_function
+re_acquire_state_context (reg_errcode_t *err, const re_dfa_t *dfa,
+			  const re_node_set *nodes, unsigned int context)
+{
+  unsigned int hash;
+  re_dfastate_t *new_state;
+  struct re_state_table_entry *spot;
+  int i;
+  if (nodes->nelem == 0)
+    {
+      *err = REG_NOERROR;
+      return NULL;
+    }
+  hash = calc_state_hash (nodes, context);
+  spot = dfa->state_table + (hash & dfa->state_hash_mask);
+
+  for (i = 0 ; i < spot->num ; i++)
+    {
+      re_dfastate_t *state = spot->array[i];
+      if (state->hash == hash
+	  && state->context == context
+	  && re_node_set_compare (state->entrance_nodes, nodes))
+	return state;
+    }
+  /* There are no appropriate state in `dfa', create the new one.  */
+  new_state = create_cd_newstate (dfa, nodes, context, hash);
+  if (BE (new_state == NULL, 0))
+    *err = REG_ESPACE;
+
+  return new_state;
+}
+
+/* Finish initialization of the new state NEWSTATE, and using its hash value
+   HASH put in the appropriate bucket of DFA's state table.  Return value
+   indicates the error code if failed.  */
+
+static reg_errcode_t
+register_state (const re_dfa_t *dfa, re_dfastate_t *newstate,
+		unsigned int hash)
+{
+  struct re_state_table_entry *spot;
+  reg_errcode_t err;
+  int i;
+
+  newstate->hash = hash;
+  err = re_node_set_alloc (&newstate->non_eps_nodes, newstate->nodes.nelem);
+  if (BE (err != REG_NOERROR, 0))
+    return REG_ESPACE;
+  for (i = 0; i < newstate->nodes.nelem; i++)
+    {
+      int elem = newstate->nodes.elems[i];
+      if (!IS_EPSILON_NODE (dfa->nodes[elem].type))
+        re_node_set_insert_last (&newstate->non_eps_nodes, elem);
+    }
+
+  spot = dfa->state_table + (hash & dfa->state_hash_mask);
+  if (BE (spot->alloc <= spot->num, 0))
+    {
+      int new_alloc = 2 * spot->num + 2;
+      re_dfastate_t **new_array = re_realloc (spot->array, re_dfastate_t *,
+					      new_alloc);
+      if (BE (new_array == NULL, 0))
+	return REG_ESPACE;
+      spot->array = new_array;
+      spot->alloc = new_alloc;
+    }
+  spot->array[spot->num++] = newstate;
+  return REG_NOERROR;
+}
+
+static void
+free_state (re_dfastate_t *state)
+{
+  re_node_set_free (&state->non_eps_nodes);
+  re_node_set_free (&state->inveclosure);
+  if (state->entrance_nodes != &state->nodes)
+    {
+      re_node_set_free (state->entrance_nodes);
+      re_free (state->entrance_nodes);
+    }
+  re_node_set_free (&state->nodes);
+  re_free (state->word_trtable);
+  re_free (state->trtable);
+  re_free (state);
+}
+
+/* Create the new state which is independ of contexts.
+   Return the new state if succeeded, otherwise return NULL.  */
+
+static re_dfastate_t *
+internal_function
+create_ci_newstate (const re_dfa_t *dfa, const re_node_set *nodes,
+		    unsigned int hash)
+{
+  int i;
+  reg_errcode_t err;
+  re_dfastate_t *newstate;
+
+  newstate = (re_dfastate_t *) calloc (sizeof (re_dfastate_t), 1);
+  if (BE (newstate == NULL, 0))
+    return NULL;
+  err = re_node_set_init_copy (&newstate->nodes, nodes);
+  if (BE (err != REG_NOERROR, 0))
+    {
+      re_free (newstate);
+      return NULL;
+    }
+
+  newstate->entrance_nodes = &newstate->nodes;
+  for (i = 0 ; i < nodes->nelem ; i++)
+    {
+      re_token_t *node = dfa->nodes + nodes->elems[i];
+      re_token_type_t type = node->type;
+      if (type == CHARACTER && !node->constraint)
+	continue;
+#ifdef RE_ENABLE_I18N
+      newstate->accept_mb |= node->accept_mb;
+#endif /* RE_ENABLE_I18N */
+
+      /* If the state has the halt node, the state is a halt state.  */
+      if (type == END_OF_RE)
+	newstate->halt = 1;
+      else if (type == OP_BACK_REF)
+	newstate->has_backref = 1;
+      else if (type == ANCHOR || node->constraint)
+	newstate->has_constraint = 1;
+    }
+  err = register_state (dfa, newstate, hash);
+  if (BE (err != REG_NOERROR, 0))
+    {
+      free_state (newstate);
+      newstate = NULL;
+    }
+  return newstate;
+}
+
+/* Create the new state which is depend on the context CONTEXT.
+   Return the new state if succeeded, otherwise return NULL.  */
+
+static re_dfastate_t *
+internal_function
+create_cd_newstate (const re_dfa_t *dfa, const re_node_set *nodes,
+		    unsigned int context, unsigned int hash)
+{
+  int i, nctx_nodes = 0;
+  reg_errcode_t err;
+  re_dfastate_t *newstate;
+
+  newstate = (re_dfastate_t *) calloc (sizeof (re_dfastate_t), 1);
+  if (BE (newstate == NULL, 0))
+    return NULL;
+  err = re_node_set_init_copy (&newstate->nodes, nodes);
+  if (BE (err != REG_NOERROR, 0))
+    {
+      re_free (newstate);
+      return NULL;
+    }
+
+  newstate->context = context;
+  newstate->entrance_nodes = &newstate->nodes;
+
+  for (i = 0 ; i < nodes->nelem ; i++)
+    {
+      unsigned int constraint = 0;
+      re_token_t *node = dfa->nodes + nodes->elems[i];
+      re_token_type_t type = node->type;
+      if (node->constraint)
+	constraint = node->constraint;
+
+      if (type == CHARACTER && !constraint)
+	continue;
+#ifdef RE_ENABLE_I18N
+      newstate->accept_mb |= node->accept_mb;
+#endif /* RE_ENABLE_I18N */
+
+      /* If the state has the halt node, the state is a halt state.  */
+      if (type == END_OF_RE)
+	newstate->halt = 1;
+      else if (type == OP_BACK_REF)
+	newstate->has_backref = 1;
+      else if (type == ANCHOR)
+	constraint = node->opr.ctx_type;
+
+      if (constraint)
+	{
+	  if (newstate->entrance_nodes == &newstate->nodes)
+	    {
+	      newstate->entrance_nodes = re_malloc (re_node_set, 1);
+	      if (BE (newstate->entrance_nodes == NULL, 0))
+		{
+		  free_state (newstate);
+		  return NULL;
+		}
+	      re_node_set_init_copy (newstate->entrance_nodes, nodes);
+	      nctx_nodes = 0;
+	      newstate->has_constraint = 1;
+	    }
+
+	  if (NOT_SATISFY_PREV_CONSTRAINT (constraint,context))
+	    {
+	      re_node_set_remove_at (&newstate->nodes, i - nctx_nodes);
+	      ++nctx_nodes;
+	    }
+	}
+    }
+  err = register_state (dfa, newstate, hash);
+  if (BE (err != REG_NOERROR, 0))
+    {
+      free_state (newstate);
+      newstate = NULL;
+    }
+  return  newstate;
+}
diff --git a/Build/source/texk/chktex/regex/regex_internal.h b/Build/source/texk/chktex/regex/regex_internal.h
new file mode 100644
index 00000000000..b0c4d355abb
--- /dev/null
+++ b/Build/source/texk/chktex/regex/regex_internal.h
@@ -0,0 +1,778 @@
+/* Extended regular expression matching and search library.
+   Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _REGEX_INTERNAL_H
+#define _REGEX_INTERNAL_H 1
+
+#include <assert.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if defined(__MINGW32_VERSION) || defined(_MSC_VER)
+#define strcasecmp stricmp
+#endif
+
+#if defined HAVE_LANGINFO_H || defined HAVE_LANGINFO_CODESET || defined _LIBC
+# include <langinfo.h>
+#endif
+#if defined HAVE_LOCALE_H || defined _LIBC
+# include <locale.h>
+#endif
+#if defined HAVE_WCHAR_H || defined _LIBC
+# include <wchar.h>
+#endif /* HAVE_WCHAR_H || _LIBC */
+#if defined HAVE_WCTYPE_H || defined _LIBC
+# include <wctype.h>
+#endif /* HAVE_WCTYPE_H || _LIBC */
+#if defined HAVE_STDBOOL_H || defined _LIBC
+# include <stdbool.h>
+#else
+typedef enum { false, true } bool;
+#endif /* HAVE_STDBOOL_H || _LIBC */
+#if defined HAVE_STDINT_H || defined _LIBC
+# include <stdint.h>
+#endif /* HAVE_STDINT_H || _LIBC */
+#if defined _LIBC
+# include <bits/libc-lock.h>
+#else
+# define __libc_lock_define(CLASS,NAME)
+# define __libc_lock_init(NAME) do { } while (0)
+# define __libc_lock_lock(NAME) do { } while (0)
+# define __libc_lock_unlock(NAME) do { } while (0)
+#endif
+
+/* In case that the system doesn't have isblank().  */
+#if !defined _LIBC && !defined HAVE_ISBLANK && !defined isblank
+# define isblank(ch) ((ch) == ' ' || (ch) == '\t')
+#endif
+
+#ifdef _LIBC
+# ifndef _RE_DEFINE_LOCALE_FUNCTIONS
+#  define _RE_DEFINE_LOCALE_FUNCTIONS 1
+#   include <locale/localeinfo.h>
+#   include <locale/elem-hash.h>
+#   include <locale/coll-lookup.h>
+# endif
+#endif
+
+/* This is for other GNU distributions with internationalized messages.  */
+#if (HAVE_LIBINTL_H && ENABLE_NLS) || defined _LIBC
+# include <libintl.h>
+# ifdef _LIBC
+#  undef gettext
+#  define gettext(msgid) \
+  INTUSE(__dcgettext) (_libc_intl_domainname, msgid, LC_MESSAGES)
+# endif
+#else
+# define gettext(msgid) (msgid)
+#endif
+
+#ifndef gettext_noop
+/* This define is so xgettext can find the internationalizable
+   strings.  */
+# define gettext_noop(String) String
+#endif
+
+/* For loser systems without the definition.  */
+#ifndef SIZE_MAX
+# define SIZE_MAX ((size_t) -1)
+#endif
+
+#if (defined MB_CUR_MAX && HAVE_LOCALE_H && HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_WCRTOMB && HAVE_MBRTOWC && HAVE_WCSCOLL) || _LIBC
+# define RE_ENABLE_I18N
+#endif
+
+#if __GNUC__ >= 3
+# define BE(expr, val) __builtin_expect (expr, val)
+#else
+# define BE(expr, val) (expr)
+# define inline
+#endif
+
+/* Number of single byte character.  */
+#define SBC_MAX 256
+
+#define COLL_ELEM_LEN_MAX 8
+
+/* The character which represents newline.  */
+#define NEWLINE_CHAR '\n'
+#define WIDE_NEWLINE_CHAR L'\n'
+
+/* Rename to standard API for using out of glibc.  */
+#ifndef _LIBC
+# define __wctype wctype
+# define __iswctype iswctype
+# define __btowc btowc
+# define __mempcpy mempcpy
+# define __wcrtomb wcrtomb
+# define __regfree regfree
+# define attribute_hidden
+#endif /* not _LIBC */
+
+#ifdef __GNUC__
+# define __attribute(arg) __attribute__ (arg)
+#else
+# define __attribute(arg)
+#endif
+
+extern const char __re_error_msgid[] attribute_hidden;
+extern const size_t __re_error_msgid_idx[] attribute_hidden;
+
+/* An integer used to represent a set of bits.  It must be unsigned,
+   and must be at least as wide as unsigned int.  */
+typedef unsigned long int bitset_word_t;
+/* All bits set in a bitset_word_t.  */
+#define BITSET_WORD_MAX ULONG_MAX
+/* Number of bits in a bitset_word_t.  */
+#define BITSET_WORD_BITS (sizeof (bitset_word_t) * CHAR_BIT)
+/* Number of bitset_word_t in a bit_set.  */
+#define BITSET_WORDS (SBC_MAX / BITSET_WORD_BITS)
+typedef bitset_word_t bitset_t[BITSET_WORDS];
+typedef bitset_word_t *re_bitset_ptr_t;
+typedef const bitset_word_t *re_const_bitset_ptr_t;
+
+#define bitset_set(set,i) \
+  (set[i / BITSET_WORD_BITS] |= (bitset_word_t) 1 << i % BITSET_WORD_BITS)
+#define bitset_clear(set,i) \
+  (set[i / BITSET_WORD_BITS] &= ~((bitset_word_t) 1 << i % BITSET_WORD_BITS))
+#define bitset_contain(set,i) \
+  (set[i / BITSET_WORD_BITS] & ((bitset_word_t) 1 << i % BITSET_WORD_BITS))
+#define bitset_empty(set) memset (set, '\0', sizeof (bitset_t))
+#define bitset_set_all(set) memset (set, '\xff', sizeof (bitset_t))
+#define bitset_copy(dest,src) memcpy (dest, src, sizeof (bitset_t))
+
+#define PREV_WORD_CONSTRAINT 0x0001
+#define PREV_NOTWORD_CONSTRAINT 0x0002
+#define NEXT_WORD_CONSTRAINT 0x0004
+#define NEXT_NOTWORD_CONSTRAINT 0x0008
+#define PREV_NEWLINE_CONSTRAINT 0x0010
+#define NEXT_NEWLINE_CONSTRAINT 0x0020
+#define PREV_BEGBUF_CONSTRAINT 0x0040
+#define NEXT_ENDBUF_CONSTRAINT 0x0080
+#define WORD_DELIM_CONSTRAINT 0x0100
+#define NOT_WORD_DELIM_CONSTRAINT 0x0200
+
+typedef enum
+{
+  INSIDE_WORD = PREV_WORD_CONSTRAINT | NEXT_WORD_CONSTRAINT,
+  WORD_FIRST = PREV_NOTWORD_CONSTRAINT | NEXT_WORD_CONSTRAINT,
+  WORD_LAST = PREV_WORD_CONSTRAINT | NEXT_NOTWORD_CONSTRAINT,
+  INSIDE_NOTWORD = PREV_NOTWORD_CONSTRAINT | NEXT_NOTWORD_CONSTRAINT,
+  LINE_FIRST = PREV_NEWLINE_CONSTRAINT,
+  LINE_LAST = NEXT_NEWLINE_CONSTRAINT,
+  BUF_FIRST = PREV_BEGBUF_CONSTRAINT,
+  BUF_LAST = NEXT_ENDBUF_CONSTRAINT,
+  WORD_DELIM = WORD_DELIM_CONSTRAINT,
+  NOT_WORD_DELIM = NOT_WORD_DELIM_CONSTRAINT
+} re_context_type;
+
+typedef struct
+{
+  int alloc;
+  int nelem;
+  int *elems;
+} re_node_set;
+
+typedef enum
+{
+  NON_TYPE = 0,
+
+  /* Node type, These are used by token, node, tree.  */
+  CHARACTER = 1,
+  END_OF_RE = 2,
+  SIMPLE_BRACKET = 3,
+  OP_BACK_REF = 4,
+  OP_PERIOD = 5,
+#ifdef RE_ENABLE_I18N
+  COMPLEX_BRACKET = 6,
+  OP_UTF8_PERIOD = 7,
+#endif /* RE_ENABLE_I18N */
+
+  /* We define EPSILON_BIT as a macro so that OP_OPEN_SUBEXP is used
+     when the debugger shows values of this enum type.  */
+#define EPSILON_BIT 8
+  OP_OPEN_SUBEXP = EPSILON_BIT | 0,
+  OP_CLOSE_SUBEXP = EPSILON_BIT | 1,
+  OP_ALT = EPSILON_BIT | 2,
+  OP_DUP_ASTERISK = EPSILON_BIT | 3,
+  ANCHOR = EPSILON_BIT | 4,
+
+  /* Tree type, these are used only by tree. */
+  CONCAT = 16,
+  SUBEXP = 17,
+
+  /* Token type, these are used only by token.  */
+  OP_DUP_PLUS = 18,
+  OP_DUP_QUESTION,
+  OP_OPEN_BRACKET,
+  OP_CLOSE_BRACKET,
+  OP_CHARSET_RANGE,
+  OP_OPEN_DUP_NUM,
+  OP_CLOSE_DUP_NUM,
+  OP_NON_MATCH_LIST,
+  OP_OPEN_COLL_ELEM,
+  OP_CLOSE_COLL_ELEM,
+  OP_OPEN_EQUIV_CLASS,
+  OP_CLOSE_EQUIV_CLASS,
+  OP_OPEN_CHAR_CLASS,
+  OP_CLOSE_CHAR_CLASS,
+  OP_WORD,
+  OP_NOTWORD,
+  OP_SPACE,
+  OP_NOTSPACE,
+  BACK_SLASH
+
+} re_token_type_t;
+
+#ifdef RE_ENABLE_I18N
+typedef struct
+{
+  /* Multibyte characters.  */
+  wchar_t *mbchars;
+
+  /* Collating symbols.  */
+# ifdef _LIBC
+  int32_t *coll_syms;
+# endif
+
+  /* Equivalence classes. */
+# ifdef _LIBC
+  int32_t *equiv_classes;
+# endif
+
+  /* Range expressions. */
+# ifdef _LIBC
+  uint32_t *range_starts;
+  uint32_t *range_ends;
+# else /* not _LIBC */
+  wchar_t *range_starts;
+  wchar_t *range_ends;
+# endif /* not _LIBC */
+
+  /* Character classes. */
+  wctype_t *char_classes;
+
+  /* If this character set is the non-matching list.  */
+  unsigned int non_match : 1;
+
+  /* # of multibyte characters.  */
+  int nmbchars;
+
+  /* # of collating symbols.  */
+  int ncoll_syms;
+
+  /* # of equivalence classes. */
+  int nequiv_classes;
+
+  /* # of range expressions. */
+  int nranges;
+
+  /* # of character classes. */
+  int nchar_classes;
+} re_charset_t;
+#endif /* RE_ENABLE_I18N */
+
+typedef struct
+{
+  union
+  {
+    unsigned char c;		/* for CHARACTER */
+    re_bitset_ptr_t sbcset;	/* for SIMPLE_BRACKET */
+#ifdef RE_ENABLE_I18N
+    re_charset_t *mbcset;	/* for COMPLEX_BRACKET */
+#endif /* RE_ENABLE_I18N */
+    int idx;			/* for BACK_REF */
+    re_context_type ctx_type;	/* for ANCHOR */
+  } opr;
+#if __GNUC__ >= 2
+  re_token_type_t type : 8;
+#else
+  re_token_type_t type;
+#endif
+  unsigned int constraint : 10;	/* context constraint */
+  unsigned int duplicated : 1;
+  unsigned int opt_subexp : 1;
+#ifdef RE_ENABLE_I18N
+  unsigned int accept_mb : 1;
+  /* These 2 bits can be moved into the union if needed (e.g. if running out
+     of bits; move opr.c to opr.c.c and move the flags to opr.c.flags).  */
+  unsigned int mb_partial : 1;
+#endif
+  unsigned int word_char : 1;
+} re_token_t;
+
+#define IS_EPSILON_NODE(type) ((type) & EPSILON_BIT)
+
+struct re_string_t
+{
+  /* Indicate the raw buffer which is the original string passed as an
+     argument of regexec(), re_search(), etc..  */
+  const unsigned char *raw_mbs;
+  /* Store the multibyte string.  In case of "case insensitive mode" like
+     REG_ICASE, upper cases of the string are stored, otherwise MBS points
+     the same address that RAW_MBS points.  */
+  unsigned char *mbs;
+#ifdef RE_ENABLE_I18N
+  /* Store the wide character string which is corresponding to MBS.  */
+  wint_t *wcs;
+  int *offsets;
+  mbstate_t cur_state;
+#endif
+  /* Index in RAW_MBS.  Each character mbs[i] corresponds to
+     raw_mbs[raw_mbs_idx + i].  */
+  int raw_mbs_idx;
+  /* The length of the valid characters in the buffers.  */
+  int valid_len;
+  /* The corresponding number of bytes in raw_mbs array.  */
+  int valid_raw_len;
+  /* The length of the buffers MBS and WCS.  */
+  int bufs_len;
+  /* The index in MBS, which is updated by re_string_fetch_byte.  */
+  int cur_idx;
+  /* length of RAW_MBS array.  */
+  int raw_len;
+  /* This is RAW_LEN - RAW_MBS_IDX + VALID_LEN - VALID_RAW_LEN.  */
+  int len;
+  /* End of the buffer may be shorter than its length in the cases such
+     as re_match_2, re_search_2.  Then, we use STOP for end of the buffer
+     instead of LEN.  */
+  int raw_stop;
+  /* This is RAW_STOP - RAW_MBS_IDX adjusted through OFFSETS.  */
+  int stop;
+
+  /* The context of mbs[0].  We store the context independently, since
+     the context of mbs[0] may be different from raw_mbs[0], which is
+     the beginning of the input string.  */
+  unsigned int tip_context;
+  /* The translation passed as a part of an argument of re_compile_pattern.  */
+  RE_TRANSLATE_TYPE trans;
+  /* Copy of re_dfa_t's word_char.  */
+  re_const_bitset_ptr_t word_char;
+  /* 1 if REG_ICASE.  */
+  unsigned char icase;
+  unsigned char is_utf8;
+  unsigned char map_notascii;
+  unsigned char mbs_allocated;
+  unsigned char offsets_needed;
+  unsigned char newline_anchor;
+  unsigned char word_ops_used;
+  int mb_cur_max;
+};
+typedef struct re_string_t re_string_t;
+
+
+struct re_dfa_t;
+typedef struct re_dfa_t re_dfa_t;
+
+#ifndef _LIBC
+# ifdef __i386__
+#  define internal_function   __attribute ((regparm (3), stdcall))
+# else
+#  define internal_function
+# endif
+#endif
+
+static reg_errcode_t re_string_realloc_buffers (re_string_t *pstr,
+						int new_buf_len)
+     internal_function;
+#ifdef RE_ENABLE_I18N
+static void build_wcs_buffer (re_string_t *pstr) internal_function;
+static int build_wcs_upper_buffer (re_string_t *pstr) internal_function;
+#endif /* RE_ENABLE_I18N */
+static void build_upper_buffer (re_string_t *pstr) internal_function;
+static void re_string_translate_buffer (re_string_t *pstr) internal_function;
+static unsigned int re_string_context_at (const re_string_t *input, int idx,
+					  int eflags)
+     internal_function __attribute ((pure));
+#define re_string_peek_byte(pstr, offset) \
+  ((pstr)->mbs[(pstr)->cur_idx + offset])
+#define re_string_fetch_byte(pstr) \
+  ((pstr)->mbs[(pstr)->cur_idx++])
+#define re_string_first_byte(pstr, idx) \
+  ((idx) == (pstr)->valid_len || (pstr)->wcs[idx] != WEOF)
+#define re_string_is_single_byte_char(pstr, idx) \
+  ((pstr)->wcs[idx] != WEOF && ((pstr)->valid_len == (idx) + 1 \
+				|| (pstr)->wcs[(idx) + 1] != WEOF))
+#define re_string_eoi(pstr) ((pstr)->stop <= (pstr)->cur_idx)
+#define re_string_cur_idx(pstr) ((pstr)->cur_idx)
+#define re_string_get_buffer(pstr) ((pstr)->mbs)
+#define re_string_length(pstr) ((pstr)->len)
+#define re_string_byte_at(pstr,idx) ((pstr)->mbs[idx])
+#define re_string_skip_bytes(pstr,idx) ((pstr)->cur_idx += (idx))
+#define re_string_set_index(pstr,idx) ((pstr)->cur_idx = (idx))
+
+#ifdef __GNUC__
+# define alloca(size)   __builtin_alloca (size)
+# define HAVE_ALLOCA 1
+#elif defined(_MSC_VER)
+# include <malloc.h>
+# define alloca _alloca
+# define HAVE_ALLOCA 1
+#else
+# error No alloca()
+#endif
+
+#ifndef _LIBC
+# if HAVE_ALLOCA
+/* The OS usually guarantees only one guard page at the bottom of the stack,
+   and a page size can be as small as 4096 bytes.  So we cannot safely
+   allocate anything larger than 4096 bytes.  Also care for the possibility
+   of a few compiler-allocated temporary stack slots.  */
+#  define __libc_use_alloca(n) ((n) < 4032)
+# else
+/* alloca is implemented with malloc, so just use malloc.  */
+#  define __libc_use_alloca(n) 0
+# endif
+#endif
+
+#define re_malloc(t,n) ((t *) malloc ((n) * sizeof (t)))
+#define re_realloc(p,t,n) ((t *) realloc (p, (n) * sizeof (t)))
+#define re_free(p) free (p)
+
+struct bin_tree_t
+{
+  struct bin_tree_t *parent;
+  struct bin_tree_t *left;
+  struct bin_tree_t *right;
+  struct bin_tree_t *first;
+  struct bin_tree_t *next;
+
+  re_token_t token;
+
+  /* `node_idx' is the index in dfa->nodes, if `type' == 0.
+     Otherwise `type' indicate the type of this node.  */
+  int node_idx;
+};
+typedef struct bin_tree_t bin_tree_t;
+
+#define BIN_TREE_STORAGE_SIZE \
+  ((1024 - sizeof (void *)) / sizeof (bin_tree_t))
+
+struct bin_tree_storage_t
+{
+  struct bin_tree_storage_t *next;
+  bin_tree_t data[BIN_TREE_STORAGE_SIZE];
+};
+typedef struct bin_tree_storage_t bin_tree_storage_t;
+
+#define CONTEXT_WORD 1
+#define CONTEXT_NEWLINE (CONTEXT_WORD << 1)
+#define CONTEXT_BEGBUF (CONTEXT_NEWLINE << 1)
+#define CONTEXT_ENDBUF (CONTEXT_BEGBUF << 1)
+
+#define IS_WORD_CONTEXT(c) ((c) & CONTEXT_WORD)
+#define IS_NEWLINE_CONTEXT(c) ((c) & CONTEXT_NEWLINE)
+#define IS_BEGBUF_CONTEXT(c) ((c) & CONTEXT_BEGBUF)
+#define IS_ENDBUF_CONTEXT(c) ((c) & CONTEXT_ENDBUF)
+#define IS_ORDINARY_CONTEXT(c) ((c) == 0)
+
+#define IS_WORD_CHAR(ch) (isalnum (ch) || (ch) == '_')
+#define IS_NEWLINE(ch) ((ch) == NEWLINE_CHAR)
+#define IS_WIDE_WORD_CHAR(ch) (iswalnum (ch) || (ch) == L'_')
+#define IS_WIDE_NEWLINE(ch) ((ch) == WIDE_NEWLINE_CHAR)
+
+#define NOT_SATISFY_PREV_CONSTRAINT(constraint,context) \
+ ((((constraint) & PREV_WORD_CONSTRAINT) && !IS_WORD_CONTEXT (context)) \
+  || ((constraint & PREV_NOTWORD_CONSTRAINT) && IS_WORD_CONTEXT (context)) \
+  || ((constraint & PREV_NEWLINE_CONSTRAINT) && !IS_NEWLINE_CONTEXT (context))\
+  || ((constraint & PREV_BEGBUF_CONSTRAINT) && !IS_BEGBUF_CONTEXT (context)))
+
+#define NOT_SATISFY_NEXT_CONSTRAINT(constraint,context) \
+ ((((constraint) & NEXT_WORD_CONSTRAINT) && !IS_WORD_CONTEXT (context)) \
+  || (((constraint) & NEXT_NOTWORD_CONSTRAINT) && IS_WORD_CONTEXT (context)) \
+  || (((constraint) & NEXT_NEWLINE_CONSTRAINT) && !IS_NEWLINE_CONTEXT (context)) \
+  || (((constraint) & NEXT_ENDBUF_CONSTRAINT) && !IS_ENDBUF_CONTEXT (context)))
+
+struct re_dfastate_t
+{
+  unsigned int hash;
+  re_node_set nodes;
+  re_node_set non_eps_nodes;
+  re_node_set inveclosure;
+  re_node_set *entrance_nodes;
+  struct re_dfastate_t **trtable, **word_trtable;
+  unsigned int context : 4;
+  unsigned int halt : 1;
+  /* If this state can accept `multi byte'.
+     Note that we refer to multibyte characters, and multi character
+     collating elements as `multi byte'.  */
+  unsigned int accept_mb : 1;
+  /* If this state has backreference node(s).  */
+  unsigned int has_backref : 1;
+  unsigned int has_constraint : 1;
+};
+typedef struct re_dfastate_t re_dfastate_t;
+
+struct re_state_table_entry
+{
+  int num;
+  int alloc;
+  re_dfastate_t **array;
+};
+
+/* Array type used in re_sub_match_last_t and re_sub_match_top_t.  */
+
+typedef struct
+{
+  int next_idx;
+  int alloc;
+  re_dfastate_t **array;
+} state_array_t;
+
+/* Store information about the node NODE whose type is OP_CLOSE_SUBEXP.  */
+
+typedef struct
+{
+  int node;
+  int str_idx; /* The position NODE match at.  */
+  state_array_t path;
+} re_sub_match_last_t;
+
+/* Store information about the node NODE whose type is OP_OPEN_SUBEXP.
+   And information about the node, whose type is OP_CLOSE_SUBEXP,
+   corresponding to NODE is stored in LASTS.  */
+
+typedef struct
+{
+  int str_idx;
+  int node;
+  state_array_t *path;
+  int alasts; /* Allocation size of LASTS.  */
+  int nlasts; /* The number of LASTS.  */
+  re_sub_match_last_t **lasts;
+} re_sub_match_top_t;
+
+struct re_backref_cache_entry
+{
+  int node;
+  int str_idx;
+  int subexp_from;
+  int subexp_to;
+  char more;
+  char unused;
+  unsigned short int eps_reachable_subexps_map;
+};
+
+typedef struct
+{
+  /* The string object corresponding to the input string.  */
+  re_string_t input;
+#if defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
+  const re_dfa_t *const dfa;
+#else
+  const re_dfa_t *dfa;
+#endif
+  /* EFLAGS of the argument of regexec.  */
+  int eflags;
+  /* Where the matching ends.  */
+  int match_last;
+  int last_node;
+  /* The state log used by the matcher.  */
+  re_dfastate_t **state_log;
+  int state_log_top;
+  /* Back reference cache.  */
+  int nbkref_ents;
+  int abkref_ents;
+  struct re_backref_cache_entry *bkref_ents;
+  int max_mb_elem_len;
+  int nsub_tops;
+  int asub_tops;
+  re_sub_match_top_t **sub_tops;
+} re_match_context_t;
+
+typedef struct
+{
+  re_dfastate_t **sifted_states;
+  re_dfastate_t **limited_states;
+  int last_node;
+  int last_str_idx;
+  re_node_set limits;
+} re_sift_context_t;
+
+struct re_fail_stack_ent_t
+{
+  int idx;
+  int node;
+  regmatch_t *regs;
+  re_node_set eps_via_nodes;
+};
+
+struct re_fail_stack_t
+{
+  int num;
+  int alloc;
+  struct re_fail_stack_ent_t *stack;
+};
+
+struct re_dfa_t
+{
+  re_token_t *nodes;
+  size_t nodes_alloc;
+  size_t nodes_len;
+  int *nexts;
+  int *org_indices;
+  re_node_set *edests;
+  re_node_set *eclosures;
+  re_node_set *inveclosures;
+  struct re_state_table_entry *state_table;
+  re_dfastate_t *init_state;
+  re_dfastate_t *init_state_word;
+  re_dfastate_t *init_state_nl;
+  re_dfastate_t *init_state_begbuf;
+  bin_tree_t *str_tree;
+  bin_tree_storage_t *str_tree_storage;
+  re_bitset_ptr_t sb_char;
+  int str_tree_storage_idx;
+
+  /* number of subexpressions `re_nsub' is in regex_t.  */
+  unsigned int state_hash_mask;
+  int init_node;
+  int nbackref; /* The number of backreference in this dfa.  */
+
+  /* Bitmap expressing which backreference is used.  */
+  bitset_word_t used_bkref_map;
+  bitset_word_t completed_bkref_map;
+
+  unsigned int has_plural_match : 1;
+  /* If this dfa has "multibyte node", which is a backreference or
+     a node which can accept multibyte character or multi character
+     collating element.  */
+  unsigned int has_mb_node : 1;
+  unsigned int is_utf8 : 1;
+  unsigned int map_notascii : 1;
+  unsigned int word_ops_used : 1;
+  int mb_cur_max;
+  bitset_t word_char;
+  reg_syntax_t syntax;
+  int *subexp_map;
+#ifdef DEBUG
+  char* re_str;
+#endif
+  __libc_lock_define (, lock)
+};
+
+#define re_node_set_init_empty(set) memset (set, '\0', sizeof (re_node_set))
+#define re_node_set_remove(set,id) \
+  (re_node_set_remove_at (set, re_node_set_contains (set, id) - 1))
+#define re_node_set_empty(p) ((p)->nelem = 0)
+#define re_node_set_free(set) re_free ((set)->elems)
+
+
+typedef enum
+{
+  SB_CHAR,
+  MB_CHAR,
+  EQUIV_CLASS,
+  COLL_SYM,
+  CHAR_CLASS
+} bracket_elem_type;
+
+typedef struct
+{
+  bracket_elem_type type;
+  union
+  {
+    unsigned char ch;
+    unsigned char *name;
+    wchar_t wch;
+  } opr;
+} bracket_elem_t;
+
+
+/* Inline functions for bitset operation.  */
+static inline void
+bitset_not (bitset_t set)
+{
+  int bitset_i;
+  for (bitset_i = 0; bitset_i < BITSET_WORDS; ++bitset_i)
+    set[bitset_i] = ~set[bitset_i];
+}
+
+static inline void
+bitset_merge (bitset_t dest, const bitset_t src)
+{
+  int bitset_i;
+  for (bitset_i = 0; bitset_i < BITSET_WORDS; ++bitset_i)
+    dest[bitset_i] |= src[bitset_i];
+}
+
+static inline void
+bitset_mask (bitset_t dest, const bitset_t src)
+{
+  int bitset_i;
+  for (bitset_i = 0; bitset_i < BITSET_WORDS; ++bitset_i)
+    dest[bitset_i] &= src[bitset_i];
+}
+
+#ifdef RE_ENABLE_I18N
+/* Inline functions for re_string.  */
+static inline int
+internal_function __attribute ((pure))
+re_string_char_size_at (const re_string_t *pstr, int idx)
+{
+  int byte_idx;
+  if (pstr->mb_cur_max == 1)
+    return 1;
+  for (byte_idx = 1; idx + byte_idx < pstr->valid_len; ++byte_idx)
+    if (pstr->wcs[idx + byte_idx] != WEOF)
+      break;
+  return byte_idx;
+}
+
+static inline wint_t
+internal_function __attribute ((pure))
+re_string_wchar_at (const re_string_t *pstr, int idx)
+{
+  if (pstr->mb_cur_max == 1)
+    return (wint_t) pstr->mbs[idx];
+  return (wint_t) pstr->wcs[idx];
+}
+
+static int
+internal_function __attribute ((pure))
+re_string_elem_size_at (const re_string_t *pstr, int idx)
+{
+# ifdef _LIBC
+  const unsigned char *p, *extra;
+  const int32_t *table, *indirect;
+  int32_t tmp;
+#  include <locale/weight.h>
+  uint_fast32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
+
+  if (nrules != 0)
+    {
+      table = (const int32_t *) _NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
+      extra = (const unsigned char *)
+	_NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB);
+      indirect = (const int32_t *) _NL_CURRENT (LC_COLLATE,
+						_NL_COLLATE_INDIRECTMB);
+      p = pstr->mbs + idx;
+      tmp = findidx (&p);
+      return p - pstr->mbs - idx;
+    }
+  else
+# endif /* _LIBC */
+    return 1;
+}
+#endif /* RE_ENABLE_I18N */
+
+#endif /*  _REGEX_INTERNAL_H */
diff --git a/Build/source/texk/chktex/regex/regexec.c b/Build/source/texk/chktex/regex/regexec.c
new file mode 100644
index 00000000000..bdfa3550a7d
--- /dev/null
+++ b/Build/source/texk/chktex/regex/regexec.c
@@ -0,0 +1,4329 @@
+/* Extended regular expression matching and search library.
+   Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Isamu Hasegawa <isamu@yamato.ibm.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+static reg_errcode_t match_ctx_init (re_match_context_t *cache, int eflags,
+				     int n) internal_function;
+static void match_ctx_clean (re_match_context_t *mctx) internal_function;
+static void match_ctx_free (re_match_context_t *cache) internal_function;
+static reg_errcode_t match_ctx_add_entry (re_match_context_t *cache, int node,
+					  int str_idx, int from, int to)
+     internal_function;
+static int search_cur_bkref_entry (const re_match_context_t *mctx, int str_idx)
+     internal_function;
+static reg_errcode_t match_ctx_add_subtop (re_match_context_t *mctx, int node,
+					   int str_idx) internal_function;
+static re_sub_match_last_t * match_ctx_add_sublast (re_sub_match_top_t *subtop,
+						   int node, int str_idx)
+     internal_function;
+static void sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
+			   re_dfastate_t **limited_sts, int last_node,
+			   int last_str_idx)
+     internal_function;
+static reg_errcode_t re_search_internal (const regex_t *preg,
+					 const char *string, int length,
+					 int start, int range, int stop,
+					 size_t nmatch, regmatch_t pmatch[],
+					 int eflags) internal_function;
+static int re_search_2_stub (struct re_pattern_buffer *bufp,
+			     const char *string1, int length1,
+			     const char *string2, int length2,
+			     int start, int range, struct re_registers *regs,
+			     int stop, int ret_len) internal_function;
+static int re_search_stub (struct re_pattern_buffer *bufp,
+			   const char *string, int length, int start,
+			   int range, int stop, struct re_registers *regs,
+			   int ret_len) internal_function;
+static unsigned re_copy_regs (struct re_registers *regs, regmatch_t *pmatch,
+			      int nregs, int regs_allocated) internal_function;
+static reg_errcode_t prune_impossible_nodes (re_match_context_t *mctx)
+     internal_function;
+static int check_matching (re_match_context_t *mctx, int fl_longest_match,
+			   int *p_match_first) internal_function;
+static int check_halt_state_context (const re_match_context_t *mctx,
+				     const re_dfastate_t *state, int idx)
+     internal_function;
+static void update_regs (const re_dfa_t *dfa, regmatch_t *pmatch,
+			 regmatch_t *prev_idx_match, int cur_node,
+			 int cur_idx, int nmatch) internal_function;
+static reg_errcode_t push_fail_stack (struct re_fail_stack_t *fs,
+				      int str_idx, int dest_node, int nregs,
+				      regmatch_t *regs,
+				      re_node_set *eps_via_nodes)
+     internal_function;
+static reg_errcode_t set_regs (const regex_t *preg,
+			       const re_match_context_t *mctx,
+			       size_t nmatch, regmatch_t *pmatch,
+			       int fl_backtrack) internal_function;
+static reg_errcode_t free_fail_stack_return (struct re_fail_stack_t *fs)
+     internal_function;
+
+#ifdef RE_ENABLE_I18N
+static int sift_states_iter_mb (const re_match_context_t *mctx,
+				re_sift_context_t *sctx,
+				int node_idx, int str_idx, int max_str_idx)
+     internal_function;
+#endif /* RE_ENABLE_I18N */
+static reg_errcode_t sift_states_backward (const re_match_context_t *mctx,
+					   re_sift_context_t *sctx)
+     internal_function;
+static reg_errcode_t build_sifted_states (const re_match_context_t *mctx,
+					  re_sift_context_t *sctx, int str_idx,
+					  re_node_set *cur_dest)
+     internal_function;
+static reg_errcode_t update_cur_sifted_state (const re_match_context_t *mctx,
+					      re_sift_context_t *sctx,
+					      int str_idx,
+					      re_node_set *dest_nodes)
+     internal_function;
+static reg_errcode_t add_epsilon_src_nodes (const re_dfa_t *dfa,
+					    re_node_set *dest_nodes,
+					    const re_node_set *candidates)
+     internal_function;
+static int check_dst_limits (const re_match_context_t *mctx,
+			     re_node_set *limits,
+			     int dst_node, int dst_idx, int src_node,
+			     int src_idx) internal_function;
+static int check_dst_limits_calc_pos_1 (const re_match_context_t *mctx,
+					int boundaries, int subexp_idx,
+					int from_node, int bkref_idx)
+     internal_function;
+static int check_dst_limits_calc_pos (const re_match_context_t *mctx,
+				      int limit, int subexp_idx,
+				      int node, int str_idx,
+				      int bkref_idx) internal_function;
+static reg_errcode_t check_subexp_limits (const re_dfa_t *dfa,
+					  re_node_set *dest_nodes,
+					  const re_node_set *candidates,
+					  re_node_set *limits,
+					  struct re_backref_cache_entry *bkref_ents,
+					  int str_idx) internal_function;
+static reg_errcode_t sift_states_bkref (const re_match_context_t *mctx,
+					re_sift_context_t *sctx,
+					int str_idx, const re_node_set *candidates)
+     internal_function;
+static reg_errcode_t merge_state_array (const re_dfa_t *dfa,
+					re_dfastate_t **dst,
+					re_dfastate_t **src, int num)
+     internal_function;
+static re_dfastate_t *find_recover_state (reg_errcode_t *err,
+					 re_match_context_t *mctx) internal_function;
+static re_dfastate_t *transit_state (reg_errcode_t *err,
+				     re_match_context_t *mctx,
+				     re_dfastate_t *state) internal_function;
+static re_dfastate_t *merge_state_with_log (reg_errcode_t *err,
+					    re_match_context_t *mctx,
+					    re_dfastate_t *next_state)
+     internal_function;
+static reg_errcode_t check_subexp_matching_top (re_match_context_t *mctx,
+						re_node_set *cur_nodes,
+						int str_idx) internal_function;
+#if 0
+static re_dfastate_t *transit_state_sb (reg_errcode_t *err,
+					re_match_context_t *mctx,
+					re_dfastate_t *pstate)
+     internal_function;
+#endif
+#ifdef RE_ENABLE_I18N
+static reg_errcode_t transit_state_mb (re_match_context_t *mctx,
+				       re_dfastate_t *pstate)
+     internal_function;
+#endif /* RE_ENABLE_I18N */
+static reg_errcode_t transit_state_bkref (re_match_context_t *mctx,
+					  const re_node_set *nodes)
+     internal_function;
+static reg_errcode_t get_subexp (re_match_context_t *mctx,
+				 int bkref_node, int bkref_str_idx)
+     internal_function;
+static reg_errcode_t get_subexp_sub (re_match_context_t *mctx,
+				     const re_sub_match_top_t *sub_top,
+				     re_sub_match_last_t *sub_last,
+				     int bkref_node, int bkref_str)
+     internal_function;
+static int find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
+			     int subexp_idx, int type) internal_function;
+static reg_errcode_t check_arrival (re_match_context_t *mctx,
+				    state_array_t *path, int top_node,
+				    int top_str, int last_node, int last_str,
+				    int type) internal_function;
+static reg_errcode_t check_arrival_add_next_nodes (re_match_context_t *mctx,
+						   int str_idx,
+						   re_node_set *cur_nodes,
+						   re_node_set *next_nodes)
+     internal_function;
+static reg_errcode_t check_arrival_expand_ecl (const re_dfa_t *dfa,
+					       re_node_set *cur_nodes,
+					       int ex_subexp, int type)
+     internal_function;
+static reg_errcode_t check_arrival_expand_ecl_sub (const re_dfa_t *dfa,
+						   re_node_set *dst_nodes,
+						   int target, int ex_subexp,
+						   int type) internal_function;
+static reg_errcode_t expand_bkref_cache (re_match_context_t *mctx,
+					 re_node_set *cur_nodes, int cur_str,
+					 int subexp_num, int type)
+     internal_function;
+static int build_trtable (const re_dfa_t *dfa,
+			  re_dfastate_t *state) internal_function;
+#ifdef RE_ENABLE_I18N
+static int check_node_accept_bytes (const re_dfa_t *dfa, int node_idx,
+				    const re_string_t *input, int idx)
+     internal_function;
+# ifdef _LIBC
+static unsigned int find_collation_sequence_value (const unsigned char *mbs,
+						   size_t name_len)
+     internal_function;
+# endif /* _LIBC */
+#endif /* RE_ENABLE_I18N */
+static int group_nodes_into_DFAstates (const re_dfa_t *dfa,
+				       const re_dfastate_t *state,
+				       re_node_set *states_node,
+				       bitset_t *states_ch) internal_function;
+static int check_node_accept (const re_match_context_t *mctx,
+			      const re_token_t *node, int idx)
+     internal_function;
+static reg_errcode_t extend_buffers (re_match_context_t *mctx)
+     internal_function;
+
+/* Entry point for POSIX code.  */
+
+/* regexec searches for a given pattern, specified by PREG, in the
+   string STRING.
+
+   If NMATCH is zero or REG_NOSUB was set in the cflags argument to
+   `regcomp', we ignore PMATCH.  Otherwise, we assume PMATCH has at
+   least NMATCH elements, and we set them to the offsets of the
+   corresponding matched substrings.
+
+   EFLAGS specifies `execution flags' which affect matching: if
+   REG_NOTBOL is set, then ^ does not match at the beginning of the
+   string; if REG_NOTEOL is set, then $ does not match at the end.
+
+   We return 0 if we find a match and REG_NOMATCH if not.  */
+
+int
+regexec (preg, string, nmatch, pmatch, eflags)
+    const regex_t *__restrict preg;
+    const char *__restrict string;
+    size_t nmatch;
+    regmatch_t pmatch[];
+    int eflags;
+{
+  reg_errcode_t err;
+  int start, length;
+  re_dfa_t *dfa = (re_dfa_t *) preg->buffer;
+
+  if (eflags & ~(REG_NOTBOL | REG_NOTEOL | REG_STARTEND))
+    return REG_BADPAT;
+
+  if (eflags & REG_STARTEND)
+    {
+      start = pmatch[0].rm_so;
+      length = pmatch[0].rm_eo;
+    }
+  else
+    {
+      start = 0;
+      length = strlen (string);
+    }
+
+  __libc_lock_lock (dfa->lock);
+  if (preg->no_sub)
+    err = re_search_internal (preg, string, length, start, length - start,
+			      length, 0, NULL, eflags);
+  else
+    err = re_search_internal (preg, string, length, start, length - start,
+			      length, nmatch, pmatch, eflags);
+  __libc_lock_unlock (dfa->lock);
+  return err != REG_NOERROR;
+}
+
+#ifdef _LIBC
+# include <shlib-compat.h>
+versioned_symbol (libc, __regexec, regexec, GLIBC_2_3_4);
+
+# if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3_4)
+__typeof__ (__regexec) __compat_regexec;
+
+int
+attribute_compat_text_section
+__compat_regexec (const regex_t *__restrict preg,
+		  const char *__restrict string, size_t nmatch,
+		  regmatch_t pmatch[], int eflags)
+{
+  return regexec (preg, string, nmatch, pmatch,
+		  eflags & (REG_NOTBOL | REG_NOTEOL));
+}
+compat_symbol (libc, __compat_regexec, regexec, GLIBC_2_0);
+# endif
+#endif
+
+/* Entry points for GNU code.  */
+
+/* re_match, re_search, re_match_2, re_search_2
+
+   The former two functions operate on STRING with length LENGTH,
+   while the later two operate on concatenation of STRING1 and STRING2
+   with lengths LENGTH1 and LENGTH2, respectively.
+
+   re_match() matches the compiled pattern in BUFP against the string,
+   starting at index START.
+
+   re_search() first tries matching at index START, then it tries to match
+   starting from index START + 1, and so on.  The last start position tried
+   is START + RANGE.  (Thus RANGE = 0 forces re_search to operate the same
+   way as re_match().)
+
+   The parameter STOP of re_{match,search}_2 specifies that no match exceeding
+   the first STOP characters of the concatenation of the strings should be
+   concerned.
+
+   If REGS is not NULL, and BUFP->no_sub is not set, the offsets of the match
+   and all groups is stroed in REGS.  (For the "_2" variants, the offsets are
+   computed relative to the concatenation, not relative to the individual
+   strings.)
+
+   On success, re_match* functions return the length of the match, re_search*
+   return the position of the start of the match.  Return value -1 means no
+   match was found and -2 indicates an internal error.  */
+
+int
+re_match (bufp, string, length, start, regs)
+    struct re_pattern_buffer *bufp;
+    const char *string;
+    int length, start;
+    struct re_registers *regs;
+{
+  return re_search_stub (bufp, string, length, start, 0, length, regs, 1);
+}
+#ifdef _LIBC
+weak_alias (__re_match, re_match)
+#endif
+
+int
+re_search (bufp, string, length, start, range, regs)
+    struct re_pattern_buffer *bufp;
+    const char *string;
+    int length, start, range;
+    struct re_registers *regs;
+{
+  return re_search_stub (bufp, string, length, start, range, length, regs, 0);
+}
+#ifdef _LIBC
+weak_alias (__re_search, re_search)
+#endif
+
+int
+re_match_2 (bufp, string1, length1, string2, length2, start, regs, stop)
+    struct re_pattern_buffer *bufp;
+    const char *string1, *string2;
+    int length1, length2, start, stop;
+    struct re_registers *regs;
+{
+  return re_search_2_stub (bufp, string1, length1, string2, length2,
+			   start, 0, regs, stop, 1);
+}
+#ifdef _LIBC
+weak_alias (__re_match_2, re_match_2)
+#endif
+
+int
+re_search_2 (bufp, string1, length1, string2, length2, start, range, regs, stop)
+    struct re_pattern_buffer *bufp;
+    const char *string1, *string2;
+    int length1, length2, start, range, stop;
+    struct re_registers *regs;
+{
+  return re_search_2_stub (bufp, string1, length1, string2, length2,
+			   start, range, regs, stop, 0);
+}
+#ifdef _LIBC
+weak_alias (__re_search_2, re_search_2)
+#endif
+
+static int
+re_search_2_stub (bufp, string1, length1, string2, length2, start, range, regs,
+		  stop, ret_len)
+    struct re_pattern_buffer *bufp;
+    const char *string1, *string2;
+    int length1, length2, start, range, stop, ret_len;
+    struct re_registers *regs;
+{
+  const char *str;
+  int rval;
+  int len = length1 + length2;
+  int free_str = 0;
+
+  if (BE (length1 < 0 || length2 < 0 || stop < 0, 0))
+    return -2;
+
+  /* Concatenate the strings.  */
+  if (length2 > 0)
+    if (length1 > 0)
+      {
+	char *s = re_malloc (char, len);
+
+	if (BE (s == NULL, 0))
+	  return -2;
+#ifdef _LIBC
+	memcpy (__mempcpy (s, string1, length1), string2, length2);
+#else
+	memcpy (s, string1, length1);
+	memcpy (s + length1, string2, length2);
+#endif
+	str = s;
+	free_str = 1;
+      }
+    else
+      str = string2;
+  else
+    str = string1;
+
+  rval = re_search_stub (bufp, str, len, start, range, stop, regs,
+			 ret_len);
+  if (free_str)
+    re_free ((char *) str);
+  return rval;
+}
+
+/* The parameters have the same meaning as those of re_search.
+   Additional parameters:
+   If RET_LEN is nonzero the length of the match is returned (re_match style);
+   otherwise the position of the match is returned.  */
+
+static int
+re_search_stub (bufp, string, length, start, range, stop, regs, ret_len)
+    struct re_pattern_buffer *bufp;
+    const char *string;
+    int length, start, range, stop, ret_len;
+    struct re_registers *regs;
+{
+  reg_errcode_t result;
+  regmatch_t *pmatch;
+  int nregs, rval;
+  int eflags = 0;
+  re_dfa_t *dfa = (re_dfa_t *) bufp->buffer;
+
+  /* Check for out-of-range.  */
+  if (BE (start < 0 || start > length, 0))
+    return -1;
+  if (BE (start + range > length, 0))
+    range = length - start;
+  else if (BE (start + range < 0, 0))
+    range = -start;
+
+  __libc_lock_lock (dfa->lock);
+
+  eflags |= (bufp->not_bol) ? REG_NOTBOL : 0;
+  eflags |= (bufp->not_eol) ? REG_NOTEOL : 0;
+
+  /* Compile fastmap if we haven't yet.  */
+  if (range > 0 && bufp->fastmap != NULL && !bufp->fastmap_accurate)
+    re_compile_fastmap (bufp);
+
+  if (BE (bufp->no_sub, 0))
+    regs = NULL;
+
+  /* We need at least 1 register.  */
+  if (regs == NULL)
+    nregs = 1;
+  else if (BE (bufp->regs_allocated == REGS_FIXED &&
+	       regs->num_regs < bufp->re_nsub + 1, 0))
+    {
+      nregs = regs->num_regs;
+      if (BE (nregs < 1, 0))
+	{
+	  /* Nothing can be copied to regs.  */
+	  regs = NULL;
+	  nregs = 1;
+	}
+    }
+  else
+    nregs = bufp->re_nsub + 1;
+  pmatch = re_malloc (regmatch_t, nregs);
+  if (BE (pmatch == NULL, 0))
+    {
+      rval = -2;
+      goto out;
+    }
+
+  result = re_search_internal (bufp, string, length, start, range, stop,
+			       nregs, pmatch, eflags);
+
+  rval = 0;
+
+  /* I hope we needn't fill ther regs with -1's when no match was found.  */
+  if (result != REG_NOERROR)
+    rval = -1;
+  else if (regs != NULL)
+    {
+      /* If caller wants register contents data back, copy them.  */
+      bufp->regs_allocated = re_copy_regs (regs, pmatch, nregs,
+					   bufp->regs_allocated);
+      if (BE (bufp->regs_allocated == REGS_UNALLOCATED, 0))
+	rval = -2;
+    }
+
+  if (BE (rval == 0, 1))
+    {
+      if (ret_len)
+	{
+	  assert (pmatch[0].rm_so == start);
+	  rval = pmatch[0].rm_eo - start;
+	}
+      else
+	rval = pmatch[0].rm_so;
+    }
+  re_free (pmatch);
+ out:
+  __libc_lock_unlock (dfa->lock);
+  return rval;
+}
+
+static unsigned
+re_copy_regs (regs, pmatch, nregs, regs_allocated)
+    struct re_registers *regs;
+    regmatch_t *pmatch;
+    int nregs, regs_allocated;
+{
+  int rval = REGS_REALLOCATE;
+  int i;
+  int need_regs = nregs + 1;
+  /* We need one extra element beyond `num_regs' for the `-1' marker GNU code
+     uses.  */
+
+  /* Have the register data arrays been allocated?  */
+  if (regs_allocated == REGS_UNALLOCATED)
+    { /* No.  So allocate them with malloc.  */
+      regs->start = re_malloc (regoff_t, need_regs);
+      regs->end = re_malloc (regoff_t, need_regs);
+      if (BE (regs->start == NULL, 0) || BE (regs->end == NULL, 0))
+	return REGS_UNALLOCATED;
+      regs->num_regs = need_regs;
+    }
+  else if (regs_allocated == REGS_REALLOCATE)
+    { /* Yes.  If we need more elements than were already
+	 allocated, reallocate them.  If we need fewer, just
+	 leave it alone.  */
+      if (BE (need_regs > regs->num_regs, 0))
+	{
+	  regoff_t *new_start = re_realloc (regs->start, regoff_t, need_regs);
+	  regoff_t *new_end = re_realloc (regs->end, regoff_t, need_regs);
+	  if (BE (new_start == NULL, 0) || BE (new_end == NULL, 0))
+	    return REGS_UNALLOCATED;
+	  regs->start = new_start;
+	  regs->end = new_end;
+	  regs->num_regs = need_regs;
+	}
+    }
+  else
+    {
+      assert (regs_allocated == REGS_FIXED);
+      /* This function may not be called with REGS_FIXED and nregs too big.  */
+      assert (regs->num_regs >= nregs);
+      rval = REGS_FIXED;
+    }
+
+  /* Copy the regs.  */
+  for (i = 0; i < nregs; ++i)
+    {
+      regs->start[i] = pmatch[i].rm_so;
+      regs->end[i] = pmatch[i].rm_eo;
+    }
+  for ( ; i < regs->num_regs; ++i)
+    regs->start[i] = regs->end[i] = -1;
+
+  return rval;
+}
+
+/* Set REGS to hold NUM_REGS registers, storing them in STARTS and
+   ENDS.  Subsequent matches using PATTERN_BUFFER and REGS will use
+   this memory for recording register information.  STARTS and ENDS
+   must be allocated using the malloc library routine, and must each
+   be at least NUM_REGS * sizeof (regoff_t) bytes long.
+
+   If NUM_REGS == 0, then subsequent matches should allocate their own
+   register data.
+
+   Unless this function is called, the first search or match using
+   PATTERN_BUFFER will allocate its own register data, without
+   freeing the old data.  */
+
+void
+re_set_registers (bufp, regs, num_regs, starts, ends)
+    struct re_pattern_buffer *bufp;
+    struct re_registers *regs;
+    unsigned num_regs;
+    regoff_t *starts, *ends;
+{
+  if (num_regs)
+    {
+      bufp->regs_allocated = REGS_REALLOCATE;
+      regs->num_regs = num_regs;
+      regs->start = starts;
+      regs->end = ends;
+    }
+  else
+    {
+      bufp->regs_allocated = REGS_UNALLOCATED;
+      regs->num_regs = 0;
+      regs->start = regs->end = (regoff_t *) 0;
+    }
+}
+#ifdef _LIBC
+weak_alias (__re_set_registers, re_set_registers)
+#endif
+
+/* Entry points compatible with 4.2 BSD regex library.  We don't define
+   them unless specifically requested.  */
+
+#if defined _REGEX_RE_COMP || defined _LIBC
+int
+# ifdef _LIBC
+weak_function
+# endif
+re_exec (s)
+     const char *s;
+{
+  return 0 == regexec (&re_comp_buf, s, 0, NULL, 0);
+}
+#endif /* _REGEX_RE_COMP */
+
+/* Internal entry point.  */
+
+/* Searches for a compiled pattern PREG in the string STRING, whose
+   length is LENGTH.  NMATCH, PMATCH, and EFLAGS have the same
+   mingings with regexec.  START, and RANGE have the same meanings
+   with re_search.
+   Return REG_NOERROR if we find a match, and REG_NOMATCH if not,
+   otherwise return the error code.
+   Note: We assume front end functions already check ranges.
+   (START + RANGE >= 0 && START + RANGE <= LENGTH)  */
+
+static reg_errcode_t
+re_search_internal (preg, string, length, start, range, stop, nmatch, pmatch,
+		    eflags)
+    const regex_t *preg;
+    const char *string;
+    int length, start, range, stop, eflags;
+    size_t nmatch;
+    regmatch_t pmatch[];
+{
+  reg_errcode_t err;
+  const re_dfa_t *dfa = (const re_dfa_t *) preg->buffer;
+  int left_lim, right_lim, incr;
+  int fl_longest_match, match_first, match_kind, match_last = -1;
+  int extra_nmatch;
+  int sb, ch;
+#if defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L)
+  re_match_context_t mctx = { .dfa = dfa };
+#else
+  re_match_context_t mctx;
+#endif
+  char *fastmap = (preg->fastmap != NULL && preg->fastmap_accurate
+		   && range && !preg->can_be_null) ? preg->fastmap : NULL;
+  RE_TRANSLATE_TYPE t = preg->translate;
+
+#if !(defined _LIBC || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
+  memset (&mctx, '\0', sizeof (re_match_context_t));
+  mctx.dfa = dfa;
+#endif
+
+  extra_nmatch = (nmatch > preg->re_nsub) ? nmatch - (preg->re_nsub + 1) : 0;
+  nmatch -= extra_nmatch;
+
+  /* Check if the DFA haven't been compiled.  */
+  if (BE (preg->used == 0 || dfa->init_state == NULL
+	  || dfa->init_state_word == NULL || dfa->init_state_nl == NULL
+	  || dfa->init_state_begbuf == NULL, 0))
+    return REG_NOMATCH;
+
+#ifdef DEBUG
+  /* We assume front-end functions already check them.  */
+  assert (start + range >= 0 && start + range <= length);
+#endif
+
+  /* If initial states with non-begbuf contexts have no elements,
+     the regex must be anchored.  If preg->newline_anchor is set,
+     we'll never use init_state_nl, so do not check it.  */
+  if (dfa->init_state->nodes.nelem == 0
+      && dfa->init_state_word->nodes.nelem == 0
+      && (dfa->init_state_nl->nodes.nelem == 0
+	  || !preg->newline_anchor))
+    {
+      if (start != 0 && start + range != 0)
+        return REG_NOMATCH;
+      start = range = 0;
+    }
+
+  /* We must check the longest matching, if nmatch > 0.  */
+  fl_longest_match = (nmatch != 0 || dfa->nbackref);
+
+  err = re_string_allocate (&mctx.input, string, length, dfa->nodes_len + 1,
+			    preg->translate, preg->syntax & RE_ICASE, dfa);
+  if (BE (err != REG_NOERROR, 0))
+    goto free_return;
+  mctx.input.stop = stop;
+  mctx.input.raw_stop = stop;
+  mctx.input.newline_anchor = preg->newline_anchor;
+
+  err = match_ctx_init (&mctx, eflags, dfa->nbackref * 2);
+  if (BE (err != REG_NOERROR, 0))
+    goto free_return;
+
+  /* We will log all the DFA states through which the dfa pass,
+     if nmatch > 1, or this dfa has "multibyte node", which is a
+     back-reference or a node which can accept multibyte character or
+     multi character collating element.  */
+  if (nmatch > 1 || dfa->has_mb_node)
+    {
+      mctx.state_log = re_malloc (re_dfastate_t *, mctx.input.bufs_len + 1);
+      if (BE (mctx.state_log == NULL, 0))
+	{
+	  err = REG_ESPACE;
+	  goto free_return;
+	}
+    }
+  else
+    mctx.state_log = NULL;
+
+  match_first = start;
+  mctx.input.tip_context = (eflags & REG_NOTBOL) ? CONTEXT_BEGBUF
+			   : CONTEXT_NEWLINE | CONTEXT_BEGBUF;
+
+  /* Check incrementally whether of not the input string match.  */
+  incr = (range < 0) ? -1 : 1;
+  left_lim = (range < 0) ? start + range : start;
+  right_lim = (range < 0) ? start : start + range;
+  sb = dfa->mb_cur_max == 1;
+  match_kind =
+    (fastmap
+     ? ((sb || !(preg->syntax & RE_ICASE || t) ? 4 : 0)
+	| (range >= 0 ? 2 : 0)
+	| (t != NULL ? 1 : 0))
+     : 8);
+
+  for (;; match_first += incr)
+    {
+      err = REG_NOMATCH;
+      if (match_first < left_lim || right_lim < match_first)
+	goto free_return;
+
+      /* Advance as rapidly as possible through the string, until we
+	 find a plausible place to start matching.  This may be done
+	 with varying efficiency, so there are various possibilities:
+	 only the most common of them are specialized, in order to
+	 save on code size.  We use a switch statement for speed.  */
+      switch (match_kind)
+	{
+	case 8:
+	  /* No fastmap.  */
+	  break;
+
+	case 7:
+	  /* Fastmap with single-byte translation, match forward.  */
+	  while (BE (match_first < right_lim, 1)
+		 && !fastmap[t[(unsigned char) string[match_first]]])
+	    ++match_first;
+	  goto forward_match_found_start_or_reached_end;
+
+	case 6:
+	  /* Fastmap without translation, match forward.  */
+	  while (BE (match_first < right_lim, 1)
+		 && !fastmap[(unsigned char) string[match_first]])
+	    ++match_first;
+
+	forward_match_found_start_or_reached_end:
+	  if (BE (match_first == right_lim, 0))
+	    {
+	      ch = match_first >= length
+		       ? 0 : (unsigned char) string[match_first];
+	      if (!fastmap[t ? t[ch] : ch])
+		goto free_return;
+	    }
+	  break;
+
+	case 4:
+	case 5:
+	  /* Fastmap without multi-byte translation, match backwards.  */
+	  while (match_first >= left_lim)
+	    {
+	      ch = match_first >= length
+		       ? 0 : (unsigned char) string[match_first];
+	      if (fastmap[t ? t[ch] : ch])
+		break;
+	      --match_first;
+	    }
+	  if (match_first < left_lim)
+	    goto free_return;
+	  break;
+
+	default:
+	  /* In this case, we can't determine easily the current byte,
+	     since it might be a component byte of a multibyte
+	     character.  Then we use the constructed buffer instead.  */
+	  for (;;)
+	    {
+	      /* If MATCH_FIRST is out of the valid range, reconstruct the
+		 buffers.  */
+	      unsigned int offset = match_first - mctx.input.raw_mbs_idx;
+	      if (BE (offset >= (unsigned int) mctx.input.valid_raw_len, 0))
+		{
+		  err = re_string_reconstruct (&mctx.input, match_first,
+					       eflags);
+		  if (BE (err != REG_NOERROR, 0))
+		    goto free_return;
+
+		  offset = match_first - mctx.input.raw_mbs_idx;
+		}
+	      /* If MATCH_FIRST is out of the buffer, leave it as '\0'.
+		 Note that MATCH_FIRST must not be smaller than 0.  */
+	      ch = (match_first >= length
+		    ? 0 : re_string_byte_at (&mctx.input, offset));
+	      if (fastmap[ch])
+		break;
+	      match_first += incr;
+	      if (match_first < left_lim || match_first > right_lim)
+	        {
+	          err = REG_NOMATCH;
+	          goto free_return;
+	        }
+	    }
+	  break;
+	}
+
+      /* Reconstruct the buffers so that the matcher can assume that
+	 the matching starts from the beginning of the buffer.  */
+      err = re_string_reconstruct (&mctx.input, match_first, eflags);
+      if (BE (err != REG_NOERROR, 0))
+	goto free_return;
+
+#ifdef RE_ENABLE_I18N
+     /* Don't consider this char as a possible match start if it part,
+	yet isn't the head, of a multibyte character.  */
+      if (!sb && !re_string_first_byte (&mctx.input, 0))
+	continue;
+#endif
+
+      /* It seems to be appropriate one, then use the matcher.  */
+      /* We assume that the matching starts from 0.  */
+      mctx.state_log_top = mctx.nbkref_ents = mctx.max_mb_elem_len = 0;
+      match_last = check_matching (&mctx, fl_longest_match,
+				   range >= 0 ? &match_first : NULL);
+      if (match_last != -1)
+	{
+	  if (BE (match_last == -2, 0))
+	    {
+	      err = REG_ESPACE;
+	      goto free_return;
+	    }
+	  else
+	    {
+	      mctx.match_last = match_last;
+	      if ((!preg->no_sub && nmatch > 1) || dfa->nbackref)
+		{
+		  re_dfastate_t *pstate = mctx.state_log[match_last];
+		  mctx.last_node = check_halt_state_context (&mctx, pstate,
+							     match_last);
+		}
+	      if ((!preg->no_sub && nmatch > 1 && dfa->has_plural_match)
+		  || dfa->nbackref)
+		{
+		  err = prune_impossible_nodes (&mctx);
+		  if (err == REG_NOERROR)
+		    break;
+		  if (BE (err != REG_NOMATCH, 0))
+		    goto free_return;
+		  match_last = -1;
+		}
+	      else
+		break; /* We found a match.  */
+	    }
+	}
+
+      match_ctx_clean (&mctx);
+    }
+
+#ifdef DEBUG
+  assert (match_last != -1);
+  assert (err == REG_NOERROR);
+#endif
+
+  /* Set pmatch[] if we need.  */
+  if (nmatch > 0)
+    {
+      int reg_idx;
+
+      /* Initialize registers.  */
+      for (reg_idx = 1; reg_idx < nmatch; ++reg_idx)
+	pmatch[reg_idx].rm_so = pmatch[reg_idx].rm_eo = -1;
+
+      /* Set the points where matching start/end.  */
+      pmatch[0].rm_so = 0;
+      pmatch[0].rm_eo = mctx.match_last;
+
+      if (!preg->no_sub && nmatch > 1)
+	{
+	  err = set_regs (preg, &mctx, nmatch, pmatch,
+			  dfa->has_plural_match && dfa->nbackref > 0);
+	  if (BE (err != REG_NOERROR, 0))
+	    goto free_return;
+	}
+
+      /* At last, add the offset to the each registers, since we slided
+	 the buffers so that we could assume that the matching starts
+	 from 0.  */
+      for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
+	if (pmatch[reg_idx].rm_so != -1)
+	  {
+#ifdef RE_ENABLE_I18N
+	    if (BE (mctx.input.offsets_needed != 0, 0))
+	      {
+		pmatch[reg_idx].rm_so =
+		  (pmatch[reg_idx].rm_so == mctx.input.valid_len
+		   ? mctx.input.valid_raw_len
+		   : mctx.input.offsets[pmatch[reg_idx].rm_so]);
+		pmatch[reg_idx].rm_eo =
+		  (pmatch[reg_idx].rm_eo == mctx.input.valid_len
+		   ? mctx.input.valid_raw_len
+		   : mctx.input.offsets[pmatch[reg_idx].rm_eo]);
+	      }
+#else
+	    assert (mctx.input.offsets_needed == 0);
+#endif
+	    pmatch[reg_idx].rm_so += match_first;
+	    pmatch[reg_idx].rm_eo += match_first;
+	  }
+      for (reg_idx = 0; reg_idx < extra_nmatch; ++reg_idx)
+	{
+	  pmatch[nmatch + reg_idx].rm_so = -1;
+	  pmatch[nmatch + reg_idx].rm_eo = -1;
+	}
+
+      if (dfa->subexp_map)
+        for (reg_idx = 0; reg_idx + 1 < nmatch; reg_idx++)
+          if (dfa->subexp_map[reg_idx] != reg_idx)
+            {
+              pmatch[reg_idx + 1].rm_so
+                = pmatch[dfa->subexp_map[reg_idx] + 1].rm_so;
+              pmatch[reg_idx + 1].rm_eo
+                = pmatch[dfa->subexp_map[reg_idx] + 1].rm_eo;
+            }
+    }
+
+ free_return:
+  re_free (mctx.state_log);
+  if (dfa->nbackref)
+    match_ctx_free (&mctx);
+  re_string_destruct (&mctx.input);
+  return err;
+}
+
+static reg_errcode_t
+prune_impossible_nodes (mctx)
+     re_match_context_t *mctx;
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int halt_node, match_last;
+  reg_errcode_t ret;
+  re_dfastate_t **sifted_states;
+  re_dfastate_t **lim_states = NULL;
+  re_sift_context_t sctx;
+#ifdef DEBUG
+  assert (mctx->state_log != NULL);
+#endif
+  match_last = mctx->match_last;
+  halt_node = mctx->last_node;
+  sifted_states = re_malloc (re_dfastate_t *, match_last + 1);
+  if (BE (sifted_states == NULL, 0))
+    {
+      ret = REG_ESPACE;
+      goto free_return;
+    }
+  if (dfa->nbackref)
+    {
+      lim_states = re_malloc (re_dfastate_t *, match_last + 1);
+      if (BE (lim_states == NULL, 0))
+	{
+	  ret = REG_ESPACE;
+	  goto free_return;
+	}
+      while (1)
+	{
+	  memset (lim_states, '\0',
+		  sizeof (re_dfastate_t *) * (match_last + 1));
+	  sift_ctx_init (&sctx, sifted_states, lim_states, halt_node,
+			 match_last);
+	  ret = sift_states_backward (mctx, &sctx);
+	  re_node_set_free (&sctx.limits);
+	  if (BE (ret != REG_NOERROR, 0))
+	      goto free_return;
+	  if (sifted_states[0] != NULL || lim_states[0] != NULL)
+	    break;
+	  do
+	    {
+	      --match_last;
+	      if (match_last < 0)
+		{
+		  ret = REG_NOMATCH;
+		  goto free_return;
+		}
+	    } while (mctx->state_log[match_last] == NULL
+		     || !mctx->state_log[match_last]->halt);
+	  halt_node = check_halt_state_context (mctx,
+						mctx->state_log[match_last],
+						match_last);
+	}
+      ret = merge_state_array (dfa, sifted_states, lim_states,
+			       match_last + 1);
+      re_free (lim_states);
+      lim_states = NULL;
+      if (BE (ret != REG_NOERROR, 0))
+	goto free_return;
+    }
+  else
+    {
+      sift_ctx_init (&sctx, sifted_states, lim_states, halt_node, match_last);
+      ret = sift_states_backward (mctx, &sctx);
+      re_node_set_free (&sctx.limits);
+      if (BE (ret != REG_NOERROR, 0))
+	goto free_return;
+    }
+  re_free (mctx->state_log);
+  mctx->state_log = sifted_states;
+  sifted_states = NULL;
+  mctx->last_node = halt_node;
+  mctx->match_last = match_last;
+  ret = REG_NOERROR;
+ free_return:
+  re_free (sifted_states);
+  re_free (lim_states);
+  return ret;
+}
+
+/* Acquire an initial state and return it.
+   We must select appropriate initial state depending on the context,
+   since initial states may have constraints like "\<", "^", etc..  */
+
+static inline re_dfastate_t *
+__attribute ((always_inline)) internal_function
+acquire_init_state_context (reg_errcode_t *err, const re_match_context_t *mctx,
+			    int idx)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  if (dfa->init_state->has_constraint)
+    {
+      unsigned int context;
+      context = re_string_context_at (&mctx->input, idx - 1, mctx->eflags);
+      if (IS_WORD_CONTEXT (context))
+	return dfa->init_state_word;
+      else if (IS_ORDINARY_CONTEXT (context))
+	return dfa->init_state;
+      else if (IS_BEGBUF_CONTEXT (context) && IS_NEWLINE_CONTEXT (context))
+	return dfa->init_state_begbuf;
+      else if (IS_NEWLINE_CONTEXT (context))
+	return dfa->init_state_nl;
+      else if (IS_BEGBUF_CONTEXT (context))
+	{
+	  /* It is relatively rare case, then calculate on demand.  */
+	  return re_acquire_state_context (err, dfa,
+					   dfa->init_state->entrance_nodes,
+					   context);
+	}
+      else
+	/* Must not happen?  */
+	return dfa->init_state;
+    }
+  else
+    return dfa->init_state;
+}
+
+/* Check whether the regular expression match input string INPUT or not,
+   and return the index where the matching end, return -1 if not match,
+   or return -2 in case of an error.
+   FL_LONGEST_MATCH means we want the POSIX longest matching.
+   If P_MATCH_FIRST is not NULL, and the match fails, it is set to the
+   next place where we may want to try matching.
+   Note that the matcher assume that the maching starts from the current
+   index of the buffer.  */
+
+static int
+internal_function
+check_matching (re_match_context_t *mctx, int fl_longest_match,
+		int *p_match_first)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  reg_errcode_t err;
+  int match = 0;
+  int match_last = -1;
+  int cur_str_idx = re_string_cur_idx (&mctx->input);
+  re_dfastate_t *cur_state;
+  int at_init_state = p_match_first != NULL;
+  int next_start_idx = cur_str_idx;
+
+  err = REG_NOERROR;
+  cur_state = acquire_init_state_context (&err, mctx, cur_str_idx);
+  /* An initial state must not be NULL (invalid).  */
+  if (BE (cur_state == NULL, 0))
+    {
+      assert (err == REG_ESPACE);
+      return -2;
+    }
+
+  if (mctx->state_log != NULL)
+    {
+      mctx->state_log[cur_str_idx] = cur_state;
+
+      /* Check OP_OPEN_SUBEXP in the initial state in case that we use them
+	 later.  E.g. Processing back references.  */
+      if (BE (dfa->nbackref, 0))
+	{
+	  at_init_state = 0;
+	  err = check_subexp_matching_top (mctx, &cur_state->nodes, 0);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+
+	  if (cur_state->has_backref)
+	    {
+	      err = transit_state_bkref (mctx, &cur_state->nodes);
+	      if (BE (err != REG_NOERROR, 0))
+	        return err;
+	    }
+	}
+    }
+
+  /* If the RE accepts NULL string.  */
+  if (BE (cur_state->halt, 0))
+    {
+      if (!cur_state->has_constraint
+	  || check_halt_state_context (mctx, cur_state, cur_str_idx))
+	{
+	  if (!fl_longest_match)
+	    return cur_str_idx;
+	  else
+	    {
+	      match_last = cur_str_idx;
+	      match = 1;
+	    }
+	}
+    }
+
+  while (!re_string_eoi (&mctx->input))
+    {
+      re_dfastate_t *old_state = cur_state;
+      int next_char_idx = re_string_cur_idx (&mctx->input) + 1;
+
+      if (BE (next_char_idx >= mctx->input.bufs_len, 0)
+          || (BE (next_char_idx >= mctx->input.valid_len, 0)
+              && mctx->input.valid_len < mctx->input.len))
+        {
+          err = extend_buffers (mctx);
+          if (BE (err != REG_NOERROR, 0))
+	    {
+	      assert (err == REG_ESPACE);
+	      return -2;
+	    }
+        }
+
+      cur_state = transit_state (&err, mctx, cur_state);
+      if (mctx->state_log != NULL)
+	cur_state = merge_state_with_log (&err, mctx, cur_state);
+
+      if (cur_state == NULL)
+	{
+	  /* Reached the invalid state or an error.  Try to recover a valid
+	     state using the state log, if available and if we have not
+	     already found a valid (even if not the longest) match.  */
+	  if (BE (err != REG_NOERROR, 0))
+	    return -2;
+
+	  if (mctx->state_log == NULL
+	      || (match && !fl_longest_match)
+	      || (cur_state = find_recover_state (&err, mctx)) == NULL)
+	    break;
+	}
+
+      if (BE (at_init_state, 0))
+	{
+	  if (old_state == cur_state)
+	    next_start_idx = next_char_idx;
+	  else
+	    at_init_state = 0;
+	}
+
+      if (cur_state->halt)
+	{
+	  /* Reached a halt state.
+	     Check the halt state can satisfy the current context.  */
+	  if (!cur_state->has_constraint
+	      || check_halt_state_context (mctx, cur_state,
+					   re_string_cur_idx (&mctx->input)))
+	    {
+	      /* We found an appropriate halt state.  */
+	      match_last = re_string_cur_idx (&mctx->input);
+	      match = 1;
+
+	      /* We found a match, do not modify match_first below.  */
+	      p_match_first = NULL;
+	      if (!fl_longest_match)
+		break;
+	    }
+	}
+    }
+
+  if (p_match_first)
+    *p_match_first += next_start_idx;
+
+  return match_last;
+}
+
+/* Check NODE match the current context.  */
+
+static int
+internal_function
+check_halt_node_context (const re_dfa_t *dfa, int node, unsigned int context)
+{
+  re_token_type_t type = dfa->nodes[node].type;
+  unsigned int constraint = dfa->nodes[node].constraint;
+  if (type != END_OF_RE)
+    return 0;
+  if (!constraint)
+    return 1;
+  if (NOT_SATISFY_NEXT_CONSTRAINT (constraint, context))
+    return 0;
+  return 1;
+}
+
+/* Check the halt state STATE match the current context.
+   Return 0 if not match, if the node, STATE has, is a halt node and
+   match the context, return the node.  */
+
+static int
+internal_function
+check_halt_state_context (const re_match_context_t *mctx,
+			  const re_dfastate_t *state, int idx)
+{
+  int i;
+  unsigned int context;
+#ifdef DEBUG
+  assert (state->halt);
+#endif
+  context = re_string_context_at (&mctx->input, idx, mctx->eflags);
+  for (i = 0; i < state->nodes.nelem; ++i)
+    if (check_halt_node_context (mctx->dfa, state->nodes.elems[i], context))
+      return state->nodes.elems[i];
+  return 0;
+}
+
+/* Compute the next node to which "NFA" transit from NODE("NFA" is a NFA
+   corresponding to the DFA).
+   Return the destination node, and update EPS_VIA_NODES, return -1 in case
+   of errors.  */
+
+static int
+internal_function
+proceed_next_node (const re_match_context_t *mctx, int nregs, regmatch_t *regs,
+		   int *pidx, int node, re_node_set *eps_via_nodes,
+		   struct re_fail_stack_t *fs)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int i, err;
+  if (IS_EPSILON_NODE (dfa->nodes[node].type))
+    {
+      re_node_set *cur_nodes = &mctx->state_log[*pidx]->nodes;
+      re_node_set *edests = &dfa->edests[node];
+      int dest_node;
+      err = re_node_set_insert (eps_via_nodes, node);
+      if (BE (err < 0, 0))
+	return -2;
+      /* Pick up a valid destination, or return -1 if none is found.  */
+      for (dest_node = -1, i = 0; i < edests->nelem; ++i)
+	{
+	  int candidate = edests->elems[i];
+	  if (!re_node_set_contains (cur_nodes, candidate))
+	    continue;
+          if (dest_node == -1)
+	    dest_node = candidate;
+
+          else
+	    {
+	      /* In order to avoid infinite loop like "(a*)*", return the second
+	         epsilon-transition if the first was already considered.  */
+	      if (re_node_set_contains (eps_via_nodes, dest_node))
+	        return candidate;
+
+	      /* Otherwise, push the second epsilon-transition on the fail stack.  */
+	      else if (fs != NULL
+		       && push_fail_stack (fs, *pidx, candidate, nregs, regs,
+				           eps_via_nodes))
+		return -2;
+
+	      /* We know we are going to exit.  */
+	      break;
+	    }
+	}
+      return dest_node;
+    }
+  else
+    {
+      int naccepted = 0;
+      re_token_type_t type = dfa->nodes[node].type;
+
+#ifdef RE_ENABLE_I18N
+      if (dfa->nodes[node].accept_mb)
+	naccepted = check_node_accept_bytes (dfa, node, &mctx->input, *pidx);
+      else
+#endif /* RE_ENABLE_I18N */
+      if (type == OP_BACK_REF)
+	{
+	  int subexp_idx = dfa->nodes[node].opr.idx + 1;
+	  naccepted = regs[subexp_idx].rm_eo - regs[subexp_idx].rm_so;
+	  if (fs != NULL)
+	    {
+	      if (regs[subexp_idx].rm_so == -1 || regs[subexp_idx].rm_eo == -1)
+		return -1;
+	      else if (naccepted)
+		{
+		  char *buf = (char *) re_string_get_buffer (&mctx->input);
+		  if (memcmp (buf + regs[subexp_idx].rm_so, buf + *pidx,
+			      naccepted) != 0)
+		    return -1;
+		}
+	    }
+
+	  if (naccepted == 0)
+	    {
+	      int dest_node;
+	      err = re_node_set_insert (eps_via_nodes, node);
+	      if (BE (err < 0, 0))
+		return -2;
+	      dest_node = dfa->edests[node].elems[0];
+	      if (re_node_set_contains (&mctx->state_log[*pidx]->nodes,
+					dest_node))
+		return dest_node;
+	    }
+	}
+
+      if (naccepted != 0
+	  || check_node_accept (mctx, dfa->nodes + node, *pidx))
+	{
+	  int dest_node = dfa->nexts[node];
+	  *pidx = (naccepted == 0) ? *pidx + 1 : *pidx + naccepted;
+	  if (fs && (*pidx > mctx->match_last || mctx->state_log[*pidx] == NULL
+		     || !re_node_set_contains (&mctx->state_log[*pidx]->nodes,
+					       dest_node)))
+	    return -1;
+	  re_node_set_empty (eps_via_nodes);
+	  return dest_node;
+	}
+    }
+  return -1;
+}
+
+static reg_errcode_t
+internal_function
+push_fail_stack (struct re_fail_stack_t *fs, int str_idx, int dest_node,
+		 int nregs, regmatch_t *regs, re_node_set *eps_via_nodes)
+{
+  reg_errcode_t err;
+  int num = fs->num++;
+  if (fs->num == fs->alloc)
+    {
+      struct re_fail_stack_ent_t *new_array;
+      new_array = realloc (fs->stack, (sizeof (struct re_fail_stack_ent_t)
+				       * fs->alloc * 2));
+      if (new_array == NULL)
+	return REG_ESPACE;
+      fs->alloc *= 2;
+      fs->stack = new_array;
+    }
+  fs->stack[num].idx = str_idx;
+  fs->stack[num].node = dest_node;
+  fs->stack[num].regs = re_malloc (regmatch_t, nregs);
+  if (fs->stack[num].regs == NULL)
+    return REG_ESPACE;
+  memcpy (fs->stack[num].regs, regs, sizeof (regmatch_t) * nregs);
+  err = re_node_set_init_copy (&fs->stack[num].eps_via_nodes, eps_via_nodes);
+  return err;
+}
+
+static int
+internal_function
+pop_fail_stack (struct re_fail_stack_t *fs, int *pidx, int nregs,
+		regmatch_t *regs, re_node_set *eps_via_nodes)
+{
+  int num = --fs->num;
+  assert (num >= 0);
+  *pidx = fs->stack[num].idx;
+  memcpy (regs, fs->stack[num].regs, sizeof (regmatch_t) * nregs);
+  re_node_set_free (eps_via_nodes);
+  re_free (fs->stack[num].regs);
+  *eps_via_nodes = fs->stack[num].eps_via_nodes;
+  return fs->stack[num].node;
+}
+
+/* Set the positions where the subexpressions are starts/ends to registers
+   PMATCH.
+   Note: We assume that pmatch[0] is already set, and
+   pmatch[i].rm_so == pmatch[i].rm_eo == -1 for 0 < i < nmatch.  */
+
+static reg_errcode_t
+internal_function
+set_regs (const regex_t *preg, const re_match_context_t *mctx, size_t nmatch,
+	  regmatch_t *pmatch, int fl_backtrack)
+{
+  const re_dfa_t *dfa = (const re_dfa_t *) preg->buffer;
+  int idx, cur_node;
+  re_node_set eps_via_nodes;
+  struct re_fail_stack_t *fs;
+  struct re_fail_stack_t fs_body = { 0, 2, NULL };
+  regmatch_t *prev_idx_match;
+  int prev_idx_match_malloced = 0;
+
+#ifdef DEBUG
+  assert (nmatch > 1);
+  assert (mctx->state_log != NULL);
+#endif
+  if (fl_backtrack)
+    {
+      fs = &fs_body;
+      fs->stack = re_malloc (struct re_fail_stack_ent_t, fs->alloc);
+      if (fs->stack == NULL)
+	return REG_ESPACE;
+    }
+  else
+    fs = NULL;
+
+  cur_node = dfa->init_node;
+  re_node_set_init_empty (&eps_via_nodes);
+
+  if (__libc_use_alloca (nmatch * sizeof (regmatch_t)))
+    prev_idx_match = (regmatch_t *) alloca (nmatch * sizeof (regmatch_t));
+  else
+    {
+      prev_idx_match = re_malloc (regmatch_t, nmatch);
+      if (prev_idx_match == NULL)
+	{
+	  free_fail_stack_return (fs);
+	  return REG_ESPACE;
+	}
+      prev_idx_match_malloced = 1;
+    }
+  memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
+
+  for (idx = pmatch[0].rm_so; idx <= pmatch[0].rm_eo ;)
+    {
+      update_regs (dfa, pmatch, prev_idx_match, cur_node, idx, nmatch);
+
+      if (idx == pmatch[0].rm_eo && cur_node == mctx->last_node)
+	{
+	  int reg_idx;
+	  if (fs)
+	    {
+	      for (reg_idx = 0; reg_idx < nmatch; ++reg_idx)
+		if (pmatch[reg_idx].rm_so > -1 && pmatch[reg_idx].rm_eo == -1)
+		  break;
+	      if (reg_idx == nmatch)
+		{
+		  re_node_set_free (&eps_via_nodes);
+		  if (prev_idx_match_malloced)
+		    re_free (prev_idx_match);
+		  return free_fail_stack_return (fs);
+		}
+	      cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
+					 &eps_via_nodes);
+	    }
+	  else
+	    {
+	      re_node_set_free (&eps_via_nodes);
+	      if (prev_idx_match_malloced)
+		re_free (prev_idx_match);
+	      return REG_NOERROR;
+	    }
+	}
+
+      /* Proceed to next node.  */
+      cur_node = proceed_next_node (mctx, nmatch, pmatch, &idx, cur_node,
+				    &eps_via_nodes, fs);
+
+      if (BE (cur_node < 0, 0))
+	{
+	  if (BE (cur_node == -2, 0))
+	    {
+	      re_node_set_free (&eps_via_nodes);
+	      if (prev_idx_match_malloced)
+		re_free (prev_idx_match);
+	      free_fail_stack_return (fs);
+	      return REG_ESPACE;
+	    }
+	  if (fs)
+	    cur_node = pop_fail_stack (fs, &idx, nmatch, pmatch,
+				       &eps_via_nodes);
+	  else
+	    {
+	      re_node_set_free (&eps_via_nodes);
+	      if (prev_idx_match_malloced)
+		re_free (prev_idx_match);
+	      return REG_NOMATCH;
+	    }
+	}
+    }
+  re_node_set_free (&eps_via_nodes);
+  if (prev_idx_match_malloced)
+    re_free (prev_idx_match);
+  return free_fail_stack_return (fs);
+}
+
+static reg_errcode_t
+internal_function
+free_fail_stack_return (struct re_fail_stack_t *fs)
+{
+  if (fs)
+    {
+      int fs_idx;
+      for (fs_idx = 0; fs_idx < fs->num; ++fs_idx)
+	{
+	  re_node_set_free (&fs->stack[fs_idx].eps_via_nodes);
+	  re_free (fs->stack[fs_idx].regs);
+	}
+      re_free (fs->stack);
+    }
+  return REG_NOERROR;
+}
+
+static void
+internal_function
+update_regs (const re_dfa_t *dfa, regmatch_t *pmatch,
+	     regmatch_t *prev_idx_match, int cur_node, int cur_idx, int nmatch)
+{
+  int type = dfa->nodes[cur_node].type;
+  if (type == OP_OPEN_SUBEXP)
+    {
+      int reg_num = dfa->nodes[cur_node].opr.idx + 1;
+
+      /* We are at the first node of this sub expression.  */
+      if (reg_num < nmatch)
+	{
+	  pmatch[reg_num].rm_so = cur_idx;
+	  pmatch[reg_num].rm_eo = -1;
+	}
+    }
+  else if (type == OP_CLOSE_SUBEXP)
+    {
+      int reg_num = dfa->nodes[cur_node].opr.idx + 1;
+      if (reg_num < nmatch)
+	{
+	  /* We are at the last node of this sub expression.  */
+	  if (pmatch[reg_num].rm_so < cur_idx)
+	    {
+	      pmatch[reg_num].rm_eo = cur_idx;
+	      /* This is a non-empty match or we are not inside an optional
+		 subexpression.  Accept this right away.  */
+	      memcpy (prev_idx_match, pmatch, sizeof (regmatch_t) * nmatch);
+	    }
+	  else
+	    {
+	      if (dfa->nodes[cur_node].opt_subexp
+		  && prev_idx_match[reg_num].rm_so != -1)
+		/* We transited through an empty match for an optional
+		   subexpression, like (a?)*, and this is not the subexp's
+		   first match.  Copy back the old content of the registers
+		   so that matches of an inner subexpression are undone as
+		   well, like in ((a?))*.  */
+		memcpy (pmatch, prev_idx_match, sizeof (regmatch_t) * nmatch);
+	      else
+		/* We completed a subexpression, but it may be part of
+		   an optional one, so do not update PREV_IDX_MATCH.  */
+		pmatch[reg_num].rm_eo = cur_idx;
+	    }
+	}
+    }
+}
+
+/* This function checks the STATE_LOG from the SCTX->last_str_idx to 0
+   and sift the nodes in each states according to the following rules.
+   Updated state_log will be wrote to STATE_LOG.
+
+   Rules: We throw away the Node `a' in the STATE_LOG[STR_IDX] if...
+     1. When STR_IDX == MATCH_LAST(the last index in the state_log):
+	If `a' isn't the LAST_NODE and `a' can't epsilon transit to
+	the LAST_NODE, we throw away the node `a'.
+     2. When 0 <= STR_IDX < MATCH_LAST and `a' accepts
+	string `s' and transit to `b':
+	i. If 'b' isn't in the STATE_LOG[STR_IDX+strlen('s')], we throw
+	   away the node `a'.
+	ii. If 'b' is in the STATE_LOG[STR_IDX+strlen('s')] but 'b' is
+	    thrown away, we throw away the node `a'.
+     3. When 0 <= STR_IDX < MATCH_LAST and 'a' epsilon transit to 'b':
+	i. If 'b' isn't in the STATE_LOG[STR_IDX], we throw away the
+	   node `a'.
+	ii. If 'b' is in the STATE_LOG[STR_IDX] but 'b' is thrown away,
+	    we throw away the node `a'.  */
+
+#define STATE_NODE_CONTAINS(state,node) \
+  ((state) != NULL && re_node_set_contains (&(state)->nodes, node))
+
+static reg_errcode_t
+internal_function
+sift_states_backward (const re_match_context_t *mctx, re_sift_context_t *sctx)
+{
+  reg_errcode_t err;
+  int null_cnt = 0;
+  int str_idx = sctx->last_str_idx;
+  re_node_set cur_dest;
+
+#ifdef DEBUG
+  assert (mctx->state_log != NULL && mctx->state_log[str_idx] != NULL);
+#endif
+
+  /* Build sifted state_log[str_idx].  It has the nodes which can epsilon
+     transit to the last_node and the last_node itself.  */
+  err = re_node_set_init_1 (&cur_dest, sctx->last_node);
+  if (BE (err != REG_NOERROR, 0))
+    return err;
+  err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
+  if (BE (err != REG_NOERROR, 0))
+    goto free_return;
+
+  /* Then check each states in the state_log.  */
+  while (str_idx > 0)
+    {
+      /* Update counters.  */
+      null_cnt = (sctx->sifted_states[str_idx] == NULL) ? null_cnt + 1 : 0;
+      if (null_cnt > mctx->max_mb_elem_len)
+	{
+	  memset (sctx->sifted_states, '\0',
+		  sizeof (re_dfastate_t *) * str_idx);
+	  re_node_set_free (&cur_dest);
+	  return REG_NOERROR;
+	}
+      re_node_set_empty (&cur_dest);
+      --str_idx;
+
+      if (mctx->state_log[str_idx])
+	{
+	  err = build_sifted_states (mctx, sctx, str_idx, &cur_dest);
+          if (BE (err != REG_NOERROR, 0))
+	    goto free_return;
+	}
+
+      /* Add all the nodes which satisfy the following conditions:
+	 - It can epsilon transit to a node in CUR_DEST.
+	 - It is in CUR_SRC.
+	 And update state_log.  */
+      err = update_cur_sifted_state (mctx, sctx, str_idx, &cur_dest);
+      if (BE (err != REG_NOERROR, 0))
+	goto free_return;
+    }
+  err = REG_NOERROR;
+ free_return:
+  re_node_set_free (&cur_dest);
+  return err;
+}
+
+static reg_errcode_t
+internal_function
+build_sifted_states (const re_match_context_t *mctx, re_sift_context_t *sctx,
+		     int str_idx, re_node_set *cur_dest)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  const re_node_set *cur_src = &mctx->state_log[str_idx]->non_eps_nodes;
+  int i;
+
+  /* Then build the next sifted state.
+     We build the next sifted state on `cur_dest', and update
+     `sifted_states[str_idx]' with `cur_dest'.
+     Note:
+     `cur_dest' is the sifted state from `state_log[str_idx + 1]'.
+     `cur_src' points the node_set of the old `state_log[str_idx]'
+     (with the epsilon nodes pre-filtered out).  */
+  for (i = 0; i < cur_src->nelem; i++)
+    {
+      int prev_node = cur_src->elems[i];
+      int naccepted = 0;
+      int ret;
+
+#ifdef DEBUG
+      re_token_type_t type = dfa->nodes[prev_node].type;
+      assert (!IS_EPSILON_NODE (type));
+#endif
+#ifdef RE_ENABLE_I18N
+      /* If the node may accept `multi byte'.  */
+      if (dfa->nodes[prev_node].accept_mb)
+	naccepted = sift_states_iter_mb (mctx, sctx, prev_node,
+					 str_idx, sctx->last_str_idx);
+#endif /* RE_ENABLE_I18N */
+
+      /* We don't check backreferences here.
+	 See update_cur_sifted_state().  */
+      if (!naccepted
+	  && check_node_accept (mctx, dfa->nodes + prev_node, str_idx)
+	  && STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + 1],
+				  dfa->nexts[prev_node]))
+	naccepted = 1;
+
+      if (naccepted == 0)
+	continue;
+
+      if (sctx->limits.nelem)
+	{
+	  int to_idx = str_idx + naccepted;
+	  if (check_dst_limits (mctx, &sctx->limits,
+				dfa->nexts[prev_node], to_idx,
+				prev_node, str_idx))
+	    continue;
+	}
+      ret = re_node_set_insert (cur_dest, prev_node);
+      if (BE (ret == -1, 0))
+	return REG_ESPACE;
+    }
+
+  return REG_NOERROR;
+}
+
+/* Helper functions.  */
+
+static reg_errcode_t
+internal_function
+clean_state_log_if_needed (re_match_context_t *mctx, int next_state_log_idx)
+{
+  int top = mctx->state_log_top;
+
+  if (next_state_log_idx >= mctx->input.bufs_len
+      || (next_state_log_idx >= mctx->input.valid_len
+	  && mctx->input.valid_len < mctx->input.len))
+    {
+      reg_errcode_t err;
+      err = extend_buffers (mctx);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+    }
+
+  if (top < next_state_log_idx)
+    {
+      memset (mctx->state_log + top + 1, '\0',
+	      sizeof (re_dfastate_t *) * (next_state_log_idx - top));
+      mctx->state_log_top = next_state_log_idx;
+    }
+  return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+merge_state_array (const re_dfa_t *dfa, re_dfastate_t **dst,
+		   re_dfastate_t **src, int num)
+{
+  int st_idx;
+  reg_errcode_t err;
+  for (st_idx = 0; st_idx < num; ++st_idx)
+    {
+      if (dst[st_idx] == NULL)
+	dst[st_idx] = src[st_idx];
+      else if (src[st_idx] != NULL)
+	{
+	  re_node_set merged_set;
+	  err = re_node_set_init_union (&merged_set, &dst[st_idx]->nodes,
+					&src[st_idx]->nodes);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+	  dst[st_idx] = re_acquire_state (&err, dfa, &merged_set);
+	  re_node_set_free (&merged_set);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+	}
+    }
+  return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+update_cur_sifted_state (const re_match_context_t *mctx,
+			 re_sift_context_t *sctx, int str_idx,
+			 re_node_set *dest_nodes)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  reg_errcode_t err = REG_NOERROR;
+  const re_node_set *candidates;
+  candidates = ((mctx->state_log[str_idx] == NULL) ? NULL
+		: &mctx->state_log[str_idx]->nodes);
+
+  if (dest_nodes->nelem == 0)
+    sctx->sifted_states[str_idx] = NULL;
+  else
+    {
+      if (candidates)
+	{
+	  /* At first, add the nodes which can epsilon transit to a node in
+	     DEST_NODE.  */
+	  err = add_epsilon_src_nodes (dfa, dest_nodes, candidates);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+
+	  /* Then, check the limitations in the current sift_context.  */
+	  if (sctx->limits.nelem)
+	    {
+	      err = check_subexp_limits (dfa, dest_nodes, candidates, &sctx->limits,
+					 mctx->bkref_ents, str_idx);
+	      if (BE (err != REG_NOERROR, 0))
+		return err;
+	    }
+	}
+
+      sctx->sifted_states[str_idx] = re_acquire_state (&err, dfa, dest_nodes);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+    }
+
+  if (candidates && mctx->state_log[str_idx]->has_backref)
+    {
+      err = sift_states_bkref (mctx, sctx, str_idx, candidates);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+    }
+  return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+add_epsilon_src_nodes (const re_dfa_t *dfa, re_node_set *dest_nodes,
+		       const re_node_set *candidates)
+{
+  reg_errcode_t err = REG_NOERROR;
+  int i;
+
+  re_dfastate_t *state = re_acquire_state (&err, dfa, dest_nodes);
+  if (BE (err != REG_NOERROR, 0))
+    return err;
+
+  if (!state->inveclosure.alloc)
+    {
+      err = re_node_set_alloc (&state->inveclosure, dest_nodes->nelem);
+      if (BE (err != REG_NOERROR, 0))
+        return REG_ESPACE;
+      for (i = 0; i < dest_nodes->nelem; i++)
+        re_node_set_merge (&state->inveclosure,
+			   dfa->inveclosures + dest_nodes->elems[i]);
+    }
+  return re_node_set_add_intersect (dest_nodes, candidates,
+				    &state->inveclosure);
+}
+
+static reg_errcode_t
+internal_function
+sub_epsilon_src_nodes (const re_dfa_t *dfa, int node, re_node_set *dest_nodes,
+		       const re_node_set *candidates)
+{
+    int ecl_idx;
+    reg_errcode_t err;
+    re_node_set *inv_eclosure = dfa->inveclosures + node;
+    re_node_set except_nodes;
+    re_node_set_init_empty (&except_nodes);
+    for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
+      {
+	int cur_node = inv_eclosure->elems[ecl_idx];
+	if (cur_node == node)
+	  continue;
+	if (IS_EPSILON_NODE (dfa->nodes[cur_node].type))
+	  {
+	    int edst1 = dfa->edests[cur_node].elems[0];
+	    int edst2 = ((dfa->edests[cur_node].nelem > 1)
+			 ? dfa->edests[cur_node].elems[1] : -1);
+	    if ((!re_node_set_contains (inv_eclosure, edst1)
+		 && re_node_set_contains (dest_nodes, edst1))
+		|| (edst2 > 0
+		    && !re_node_set_contains (inv_eclosure, edst2)
+		    && re_node_set_contains (dest_nodes, edst2)))
+	      {
+		err = re_node_set_add_intersect (&except_nodes, candidates,
+						 dfa->inveclosures + cur_node);
+		if (BE (err != REG_NOERROR, 0))
+		  {
+		    re_node_set_free (&except_nodes);
+		    return err;
+		  }
+	      }
+	  }
+      }
+    for (ecl_idx = 0; ecl_idx < inv_eclosure->nelem; ++ecl_idx)
+      {
+	int cur_node = inv_eclosure->elems[ecl_idx];
+	if (!re_node_set_contains (&except_nodes, cur_node))
+	  {
+	    int idx = re_node_set_contains (dest_nodes, cur_node) - 1;
+	    re_node_set_remove_at (dest_nodes, idx);
+	  }
+      }
+    re_node_set_free (&except_nodes);
+    return REG_NOERROR;
+}
+
+static int
+internal_function
+check_dst_limits (const re_match_context_t *mctx, re_node_set *limits,
+		  int dst_node, int dst_idx, int src_node, int src_idx)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int lim_idx, src_pos, dst_pos;
+
+  int dst_bkref_idx = search_cur_bkref_entry (mctx, dst_idx);
+  int src_bkref_idx = search_cur_bkref_entry (mctx, src_idx);
+  for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
+    {
+      int subexp_idx;
+      struct re_backref_cache_entry *ent;
+      ent = mctx->bkref_ents + limits->elems[lim_idx];
+      subexp_idx = dfa->nodes[ent->node].opr.idx;
+
+      dst_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
+					   subexp_idx, dst_node, dst_idx,
+					   dst_bkref_idx);
+      src_pos = check_dst_limits_calc_pos (mctx, limits->elems[lim_idx],
+					   subexp_idx, src_node, src_idx,
+					   src_bkref_idx);
+
+      /* In case of:
+	 <src> <dst> ( <subexp> )
+	 ( <subexp> ) <src> <dst>
+	 ( <subexp1> <src> <subexp2> <dst> <subexp3> )  */
+      if (src_pos == dst_pos)
+	continue; /* This is unrelated limitation.  */
+      else
+	return 1;
+    }
+  return 0;
+}
+
+static int
+internal_function
+check_dst_limits_calc_pos_1 (const re_match_context_t *mctx, int boundaries,
+			     int subexp_idx, int from_node, int bkref_idx)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  const re_node_set *eclosures = dfa->eclosures + from_node;
+  int node_idx;
+
+  /* Else, we are on the boundary: examine the nodes on the epsilon
+     closure.  */
+  for (node_idx = 0; node_idx < eclosures->nelem; ++node_idx)
+    {
+      int node = eclosures->elems[node_idx];
+      switch (dfa->nodes[node].type)
+	{
+	case OP_BACK_REF:
+	  if (bkref_idx != -1)
+	    {
+	      struct re_backref_cache_entry *ent = mctx->bkref_ents + bkref_idx;
+	      do
+	        {
+		  int dst, cpos;
+
+		  if (ent->node != node)
+		    continue;
+
+		  if (subexp_idx < BITSET_WORD_BITS
+		      && !(ent->eps_reachable_subexps_map
+			   & ((bitset_word_t) 1 << subexp_idx)))
+		    continue;
+
+		  /* Recurse trying to reach the OP_OPEN_SUBEXP and
+		     OP_CLOSE_SUBEXP cases below.  But, if the
+		     destination node is the same node as the source
+		     node, don't recurse because it would cause an
+		     infinite loop: a regex that exhibits this behavior
+		     is ()\1*\1*  */
+		  dst = dfa->edests[node].elems[0];
+		  if (dst == from_node)
+		    {
+		      if (boundaries & 1)
+		        return -1;
+		      else /* if (boundaries & 2) */
+		        return 0;
+		    }
+
+		  cpos =
+		    check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
+						 dst, bkref_idx);
+		  if (cpos == -1 /* && (boundaries & 1) */)
+		    return -1;
+		  if (cpos == 0 && (boundaries & 2))
+		    return 0;
+
+		  if (subexp_idx < BITSET_WORD_BITS)
+		    ent->eps_reachable_subexps_map
+		      &= ~((bitset_word_t) 1 << subexp_idx);
+	        }
+	      while (ent++->more);
+	    }
+	  break;
+
+	case OP_OPEN_SUBEXP:
+	  if ((boundaries & 1) && subexp_idx == dfa->nodes[node].opr.idx)
+	    return -1;
+	  break;
+
+	case OP_CLOSE_SUBEXP:
+	  if ((boundaries & 2) && subexp_idx == dfa->nodes[node].opr.idx)
+	    return 0;
+	  break;
+
+	default:
+	    break;
+	}
+    }
+
+  return (boundaries & 2) ? 1 : 0;
+}
+
+static int
+internal_function
+check_dst_limits_calc_pos (const re_match_context_t *mctx, int limit,
+			   int subexp_idx, int from_node, int str_idx,
+			   int bkref_idx)
+{
+  struct re_backref_cache_entry *lim = mctx->bkref_ents + limit;
+  int boundaries;
+
+  /* If we are outside the range of the subexpression, return -1 or 1.  */
+  if (str_idx < lim->subexp_from)
+    return -1;
+
+  if (lim->subexp_to < str_idx)
+    return 1;
+
+  /* If we are within the subexpression, return 0.  */
+  boundaries = (str_idx == lim->subexp_from);
+  boundaries |= (str_idx == lim->subexp_to) << 1;
+  if (boundaries == 0)
+    return 0;
+
+  /* Else, examine epsilon closure.  */
+  return check_dst_limits_calc_pos_1 (mctx, boundaries, subexp_idx,
+				      from_node, bkref_idx);
+}
+
+/* Check the limitations of sub expressions LIMITS, and remove the nodes
+   which are against limitations from DEST_NODES. */
+
+static reg_errcode_t
+internal_function
+check_subexp_limits (const re_dfa_t *dfa, re_node_set *dest_nodes,
+		     const re_node_set *candidates, re_node_set *limits,
+		     struct re_backref_cache_entry *bkref_ents, int str_idx)
+{
+  reg_errcode_t err;
+  int node_idx, lim_idx;
+
+  for (lim_idx = 0; lim_idx < limits->nelem; ++lim_idx)
+    {
+      int subexp_idx;
+      struct re_backref_cache_entry *ent;
+      ent = bkref_ents + limits->elems[lim_idx];
+
+      if (str_idx <= ent->subexp_from || ent->str_idx < str_idx)
+	continue; /* This is unrelated limitation.  */
+
+      subexp_idx = dfa->nodes[ent->node].opr.idx;
+      if (ent->subexp_to == str_idx)
+	{
+	  int ops_node = -1;
+	  int cls_node = -1;
+	  for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
+	    {
+	      int node = dest_nodes->elems[node_idx];
+	      re_token_type_t type = dfa->nodes[node].type;
+	      if (type == OP_OPEN_SUBEXP
+		  && subexp_idx == dfa->nodes[node].opr.idx)
+		ops_node = node;
+	      else if (type == OP_CLOSE_SUBEXP
+		       && subexp_idx == dfa->nodes[node].opr.idx)
+		cls_node = node;
+	    }
+
+	  /* Check the limitation of the open subexpression.  */
+	  /* Note that (ent->subexp_to = str_idx != ent->subexp_from).  */
+	  if (ops_node >= 0)
+	    {
+	      err = sub_epsilon_src_nodes (dfa, ops_node, dest_nodes,
+					   candidates);
+	      if (BE (err != REG_NOERROR, 0))
+		return err;
+	    }
+
+	  /* Check the limitation of the close subexpression.  */
+	  if (cls_node >= 0)
+	    for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
+	      {
+		int node = dest_nodes->elems[node_idx];
+		if (!re_node_set_contains (dfa->inveclosures + node,
+					   cls_node)
+		    && !re_node_set_contains (dfa->eclosures + node,
+					      cls_node))
+		  {
+		    /* It is against this limitation.
+		       Remove it form the current sifted state.  */
+		    err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
+						 candidates);
+		    if (BE (err != REG_NOERROR, 0))
+		      return err;
+		    --node_idx;
+		  }
+	      }
+	}
+      else /* (ent->subexp_to != str_idx)  */
+	{
+	  for (node_idx = 0; node_idx < dest_nodes->nelem; ++node_idx)
+	    {
+	      int node = dest_nodes->elems[node_idx];
+	      re_token_type_t type = dfa->nodes[node].type;
+	      if (type == OP_CLOSE_SUBEXP || type == OP_OPEN_SUBEXP)
+		{
+		  if (subexp_idx != dfa->nodes[node].opr.idx)
+		    continue;
+		  /* It is against this limitation.
+		     Remove it form the current sifted state.  */
+		  err = sub_epsilon_src_nodes (dfa, node, dest_nodes,
+					       candidates);
+		  if (BE (err != REG_NOERROR, 0))
+		    return err;
+		}
+	    }
+	}
+    }
+  return REG_NOERROR;
+}
+
+static reg_errcode_t
+internal_function
+sift_states_bkref (const re_match_context_t *mctx, re_sift_context_t *sctx,
+		   int str_idx, const re_node_set *candidates)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  reg_errcode_t err;
+  int node_idx, node;
+  re_sift_context_t local_sctx;
+  int first_idx = search_cur_bkref_entry (mctx, str_idx);
+
+  if (first_idx == -1)
+    return REG_NOERROR;
+
+  local_sctx.sifted_states = NULL; /* Mark that it hasn't been initialized.  */
+
+  for (node_idx = 0; node_idx < candidates->nelem; ++node_idx)
+    {
+      int enabled_idx;
+      re_token_type_t type;
+      struct re_backref_cache_entry *entry;
+      node = candidates->elems[node_idx];
+      type = dfa->nodes[node].type;
+      /* Avoid infinite loop for the REs like "()\1+".  */
+      if (node == sctx->last_node && str_idx == sctx->last_str_idx)
+	continue;
+      if (type != OP_BACK_REF)
+	continue;
+
+      entry = mctx->bkref_ents + first_idx;
+      enabled_idx = first_idx;
+      do
+	{
+	  int subexp_len;
+	  int to_idx;
+	  int dst_node;
+	  int ret;
+	  re_dfastate_t *cur_state;
+
+	  if (entry->node != node)
+	    continue;
+	  subexp_len = entry->subexp_to - entry->subexp_from;
+	  to_idx = str_idx + subexp_len;
+	  dst_node = (subexp_len ? dfa->nexts[node]
+		      : dfa->edests[node].elems[0]);
+
+	  if (to_idx > sctx->last_str_idx
+	      || sctx->sifted_states[to_idx] == NULL
+	      || !STATE_NODE_CONTAINS (sctx->sifted_states[to_idx], dst_node)
+	      || check_dst_limits (mctx, &sctx->limits, node,
+				   str_idx, dst_node, to_idx))
+	    continue;
+
+	  if (local_sctx.sifted_states == NULL)
+	    {
+	      local_sctx = *sctx;
+	      err = re_node_set_init_copy (&local_sctx.limits, &sctx->limits);
+	      if (BE (err != REG_NOERROR, 0))
+		goto free_return;
+	    }
+	  local_sctx.last_node = node;
+	  local_sctx.last_str_idx = str_idx;
+	  ret = re_node_set_insert (&local_sctx.limits, enabled_idx);
+	  if (BE (ret < 0, 0))
+	    {
+	      err = REG_ESPACE;
+	      goto free_return;
+	    }
+	  cur_state = local_sctx.sifted_states[str_idx];
+	  err = sift_states_backward (mctx, &local_sctx);
+	  if (BE (err != REG_NOERROR, 0))
+	    goto free_return;
+	  if (sctx->limited_states != NULL)
+	    {
+	      err = merge_state_array (dfa, sctx->limited_states,
+				       local_sctx.sifted_states,
+				       str_idx + 1);
+	      if (BE (err != REG_NOERROR, 0))
+		goto free_return;
+	    }
+	  local_sctx.sifted_states[str_idx] = cur_state;
+	  re_node_set_remove (&local_sctx.limits, enabled_idx);
+
+	  /* mctx->bkref_ents may have changed, reload the pointer.  */
+          entry = mctx->bkref_ents + enabled_idx;
+	}
+      while (enabled_idx++, entry++->more);
+    }
+  err = REG_NOERROR;
+ free_return:
+  if (local_sctx.sifted_states != NULL)
+    {
+      re_node_set_free (&local_sctx.limits);
+    }
+
+  return err;
+}
+
+
+#ifdef RE_ENABLE_I18N
+static int
+internal_function
+sift_states_iter_mb (const re_match_context_t *mctx, re_sift_context_t *sctx,
+		     int node_idx, int str_idx, int max_str_idx)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int naccepted;
+  /* Check the node can accept `multi byte'.  */
+  naccepted = check_node_accept_bytes (dfa, node_idx, &mctx->input, str_idx);
+  if (naccepted > 0 && str_idx + naccepted <= max_str_idx &&
+      !STATE_NODE_CONTAINS (sctx->sifted_states[str_idx + naccepted],
+			    dfa->nexts[node_idx]))
+    /* The node can't accept the `multi byte', or the
+       destination was already thrown away, then the node
+       could't accept the current input `multi byte'.   */
+    naccepted = 0;
+  /* Otherwise, it is sure that the node could accept
+     `naccepted' bytes input.  */
+  return naccepted;
+}
+#endif /* RE_ENABLE_I18N */
+
+
+/* Functions for state transition.  */
+
+/* Return the next state to which the current state STATE will transit by
+   accepting the current input byte, and update STATE_LOG if necessary.
+   If STATE can accept a multibyte char/collating element/back reference
+   update the destination of STATE_LOG.  */
+
+static re_dfastate_t *
+internal_function
+transit_state (reg_errcode_t *err, re_match_context_t *mctx,
+	       re_dfastate_t *state)
+{
+  re_dfastate_t **trtable;
+  unsigned char ch;
+
+#ifdef RE_ENABLE_I18N
+  /* If the current state can accept multibyte.  */
+  if (BE (state->accept_mb, 0))
+    {
+      *err = transit_state_mb (mctx, state);
+      if (BE (*err != REG_NOERROR, 0))
+	return NULL;
+    }
+#endif /* RE_ENABLE_I18N */
+
+  /* Then decide the next state with the single byte.  */
+#if 0
+  if (0)
+    /* don't use transition table  */
+    return transit_state_sb (err, mctx, state);
+#endif
+
+  /* Use transition table  */
+  ch = re_string_fetch_byte (&mctx->input);
+  for (;;)
+    {
+      trtable = state->trtable;
+      if (BE (trtable != NULL, 1))
+	return trtable[ch];
+
+      trtable = state->word_trtable;
+      if (BE (trtable != NULL, 1))
+        {
+	  unsigned int context;
+	  context
+	    = re_string_context_at (&mctx->input,
+				    re_string_cur_idx (&mctx->input) - 1,
+				    mctx->eflags);
+	  if (IS_WORD_CONTEXT (context))
+	    return trtable[ch + SBC_MAX];
+	  else
+	    return trtable[ch];
+	}
+
+      if (!build_trtable (mctx->dfa, state))
+	{
+	  *err = REG_ESPACE;
+	  return NULL;
+	}
+
+      /* Retry, we now have a transition table.  */
+    }
+}
+
+/* Update the state_log if we need */
+re_dfastate_t *
+internal_function
+merge_state_with_log (reg_errcode_t *err, re_match_context_t *mctx,
+		      re_dfastate_t *next_state)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int cur_idx = re_string_cur_idx (&mctx->input);
+
+  if (cur_idx > mctx->state_log_top)
+    {
+      mctx->state_log[cur_idx] = next_state;
+      mctx->state_log_top = cur_idx;
+    }
+  else if (mctx->state_log[cur_idx] == 0)
+    {
+      mctx->state_log[cur_idx] = next_state;
+    }
+  else
+    {
+      re_dfastate_t *pstate;
+      unsigned int context;
+      re_node_set next_nodes, *log_nodes, *table_nodes = NULL;
+      /* If (state_log[cur_idx] != 0), it implies that cur_idx is
+         the destination of a multibyte char/collating element/
+         back reference.  Then the next state is the union set of
+         these destinations and the results of the transition table.  */
+      pstate = mctx->state_log[cur_idx];
+      log_nodes = pstate->entrance_nodes;
+      if (next_state != NULL)
+        {
+          table_nodes = next_state->entrance_nodes;
+          *err = re_node_set_init_union (&next_nodes, table_nodes,
+					     log_nodes);
+          if (BE (*err != REG_NOERROR, 0))
+	    return NULL;
+        }
+      else
+        next_nodes = *log_nodes;
+      /* Note: We already add the nodes of the initial state,
+	 then we don't need to add them here.  */
+
+      context = re_string_context_at (&mctx->input,
+				      re_string_cur_idx (&mctx->input) - 1,
+				      mctx->eflags);
+      next_state = mctx->state_log[cur_idx]
+        = re_acquire_state_context (err, dfa, &next_nodes, context);
+      /* We don't need to check errors here, since the return value of
+         this function is next_state and ERR is already set.  */
+
+      if (table_nodes != NULL)
+        re_node_set_free (&next_nodes);
+    }
+
+  if (BE (dfa->nbackref, 0) && next_state != NULL)
+    {
+      /* Check OP_OPEN_SUBEXP in the current state in case that we use them
+	 later.  We must check them here, since the back references in the
+	 next state might use them.  */
+      *err = check_subexp_matching_top (mctx, &next_state->nodes,
+					cur_idx);
+      if (BE (*err != REG_NOERROR, 0))
+	return NULL;
+
+      /* If the next state has back references.  */
+      if (next_state->has_backref)
+	{
+	  *err = transit_state_bkref (mctx, &next_state->nodes);
+	  if (BE (*err != REG_NOERROR, 0))
+	    return NULL;
+	  next_state = mctx->state_log[cur_idx];
+	}
+    }
+
+  return next_state;
+}
+
+/* Skip bytes in the input that correspond to part of a
+   multi-byte match, then look in the log for a state
+   from which to restart matching.  */
+re_dfastate_t *
+internal_function
+find_recover_state (reg_errcode_t *err, re_match_context_t *mctx)
+{
+  re_dfastate_t *cur_state;
+  do
+    {
+      int max = mctx->state_log_top;
+      int cur_str_idx = re_string_cur_idx (&mctx->input);
+
+      do
+	{
+          if (++cur_str_idx > max)
+            return NULL;
+          re_string_skip_bytes (&mctx->input, 1);
+	}
+      while (mctx->state_log[cur_str_idx] == NULL);
+
+      cur_state = merge_state_with_log (err, mctx, NULL);
+    }
+  while (*err == REG_NOERROR && cur_state == NULL);
+  return cur_state;
+}
+
+/* Helper functions for transit_state.  */
+
+/* From the node set CUR_NODES, pick up the nodes whose types are
+   OP_OPEN_SUBEXP and which have corresponding back references in the regular
+   expression. And register them to use them later for evaluating the
+   correspoding back references.  */
+
+static reg_errcode_t
+internal_function
+check_subexp_matching_top (re_match_context_t *mctx, re_node_set *cur_nodes,
+			   int str_idx)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int node_idx;
+  reg_errcode_t err;
+
+  /* TODO: This isn't efficient.
+	   Because there might be more than one nodes whose types are
+	   OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
+	   nodes.
+	   E.g. RE: (a){2}  */
+  for (node_idx = 0; node_idx < cur_nodes->nelem; ++node_idx)
+    {
+      int node = cur_nodes->elems[node_idx];
+      if (dfa->nodes[node].type == OP_OPEN_SUBEXP
+	  && dfa->nodes[node].opr.idx < BITSET_WORD_BITS
+	  && (dfa->used_bkref_map
+	      & ((bitset_word_t) 1 << dfa->nodes[node].opr.idx)))
+	{
+	  err = match_ctx_add_subtop (mctx, node, str_idx);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+	}
+    }
+  return REG_NOERROR;
+}
+
+#if 0
+/* Return the next state to which the current state STATE will transit by
+   accepting the current input byte.  */
+
+static re_dfastate_t *
+transit_state_sb (reg_errcode_t *err, re_match_context_t *mctx,
+		  re_dfastate_t *state)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  re_node_set next_nodes;
+  re_dfastate_t *next_state;
+  int node_cnt, cur_str_idx = re_string_cur_idx (&mctx->input);
+  unsigned int context;
+
+  *err = re_node_set_alloc (&next_nodes, state->nodes.nelem + 1);
+  if (BE (*err != REG_NOERROR, 0))
+    return NULL;
+  for (node_cnt = 0; node_cnt < state->nodes.nelem; ++node_cnt)
+    {
+      int cur_node = state->nodes.elems[node_cnt];
+      if (check_node_accept (mctx, dfa->nodes + cur_node, cur_str_idx))
+	{
+	  *err = re_node_set_merge (&next_nodes,
+				    dfa->eclosures + dfa->nexts[cur_node]);
+	  if (BE (*err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&next_nodes);
+	      return NULL;
+	    }
+	}
+    }
+  context = re_string_context_at (&mctx->input, cur_str_idx, mctx->eflags);
+  next_state = re_acquire_state_context (err, dfa, &next_nodes, context);
+  /* We don't need to check errors here, since the return value of
+     this function is next_state and ERR is already set.  */
+
+  re_node_set_free (&next_nodes);
+  re_string_skip_bytes (&mctx->input, 1);
+  return next_state;
+}
+#endif
+
+#ifdef RE_ENABLE_I18N
+static reg_errcode_t
+internal_function
+transit_state_mb (re_match_context_t *mctx, re_dfastate_t *pstate)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  reg_errcode_t err;
+  int i;
+
+  for (i = 0; i < pstate->nodes.nelem; ++i)
+    {
+      re_node_set dest_nodes, *new_nodes;
+      int cur_node_idx = pstate->nodes.elems[i];
+      int naccepted, dest_idx;
+      unsigned int context;
+      re_dfastate_t *dest_state;
+
+      if (!dfa->nodes[cur_node_idx].accept_mb)
+        continue;
+
+      if (dfa->nodes[cur_node_idx].constraint)
+	{
+	  context = re_string_context_at (&mctx->input,
+					  re_string_cur_idx (&mctx->input),
+					  mctx->eflags);
+	  if (NOT_SATISFY_NEXT_CONSTRAINT (dfa->nodes[cur_node_idx].constraint,
+					   context))
+	    continue;
+	}
+
+      /* How many bytes the node can accept?  */
+      naccepted = check_node_accept_bytes (dfa, cur_node_idx, &mctx->input,
+					   re_string_cur_idx (&mctx->input));
+      if (naccepted == 0)
+	continue;
+
+      /* The node can accepts `naccepted' bytes.  */
+      dest_idx = re_string_cur_idx (&mctx->input) + naccepted;
+      mctx->max_mb_elem_len = ((mctx->max_mb_elem_len < naccepted) ? naccepted
+			       : mctx->max_mb_elem_len);
+      err = clean_state_log_if_needed (mctx, dest_idx);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+#ifdef DEBUG
+      assert (dfa->nexts[cur_node_idx] != -1);
+#endif
+      new_nodes = dfa->eclosures + dfa->nexts[cur_node_idx];
+
+      dest_state = mctx->state_log[dest_idx];
+      if (dest_state == NULL)
+	dest_nodes = *new_nodes;
+      else
+	{
+	  err = re_node_set_init_union (&dest_nodes,
+					dest_state->entrance_nodes, new_nodes);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+	}
+      context = re_string_context_at (&mctx->input, dest_idx - 1,
+				      mctx->eflags);
+      mctx->state_log[dest_idx]
+	= re_acquire_state_context (&err, dfa, &dest_nodes, context);
+      if (dest_state != NULL)
+	re_node_set_free (&dest_nodes);
+      if (BE (mctx->state_log[dest_idx] == NULL && err != REG_NOERROR, 0))
+	return err;
+    }
+  return REG_NOERROR;
+}
+#endif /* RE_ENABLE_I18N */
+
+static reg_errcode_t
+internal_function
+transit_state_bkref (re_match_context_t *mctx, const re_node_set *nodes)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  reg_errcode_t err;
+  int i;
+  int cur_str_idx = re_string_cur_idx (&mctx->input);
+
+  for (i = 0; i < nodes->nelem; ++i)
+    {
+      int dest_str_idx, prev_nelem, bkc_idx;
+      int node_idx = nodes->elems[i];
+      unsigned int context;
+      const re_token_t *node = dfa->nodes + node_idx;
+      re_node_set *new_dest_nodes;
+
+      /* Check whether `node' is a backreference or not.  */
+      if (node->type != OP_BACK_REF)
+	continue;
+
+      if (node->constraint)
+	{
+	  context = re_string_context_at (&mctx->input, cur_str_idx,
+					  mctx->eflags);
+	  if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
+	    continue;
+	}
+
+      /* `node' is a backreference.
+	 Check the substring which the substring matched.  */
+      bkc_idx = mctx->nbkref_ents;
+      err = get_subexp (mctx, node_idx, cur_str_idx);
+      if (BE (err != REG_NOERROR, 0))
+	goto free_return;
+
+      /* And add the epsilon closures (which is `new_dest_nodes') of
+	 the backreference to appropriate state_log.  */
+#ifdef DEBUG
+      assert (dfa->nexts[node_idx] != -1);
+#endif
+      for (; bkc_idx < mctx->nbkref_ents; ++bkc_idx)
+	{
+	  int subexp_len;
+	  re_dfastate_t *dest_state;
+	  struct re_backref_cache_entry *bkref_ent;
+	  bkref_ent = mctx->bkref_ents + bkc_idx;
+	  if (bkref_ent->node != node_idx || bkref_ent->str_idx != cur_str_idx)
+	    continue;
+	  subexp_len = bkref_ent->subexp_to - bkref_ent->subexp_from;
+	  new_dest_nodes = (subexp_len == 0
+			    ? dfa->eclosures + dfa->edests[node_idx].elems[0]
+			    : dfa->eclosures + dfa->nexts[node_idx]);
+	  dest_str_idx = (cur_str_idx + bkref_ent->subexp_to
+			  - bkref_ent->subexp_from);
+	  context = re_string_context_at (&mctx->input, dest_str_idx - 1,
+					  mctx->eflags);
+	  dest_state = mctx->state_log[dest_str_idx];
+	  prev_nelem = ((mctx->state_log[cur_str_idx] == NULL) ? 0
+			: mctx->state_log[cur_str_idx]->nodes.nelem);
+	  /* Add `new_dest_node' to state_log.  */
+	  if (dest_state == NULL)
+	    {
+	      mctx->state_log[dest_str_idx]
+		= re_acquire_state_context (&err, dfa, new_dest_nodes,
+					    context);
+	      if (BE (mctx->state_log[dest_str_idx] == NULL
+		      && err != REG_NOERROR, 0))
+		goto free_return;
+	    }
+	  else
+	    {
+	      re_node_set dest_nodes;
+	      err = re_node_set_init_union (&dest_nodes,
+					    dest_state->entrance_nodes,
+					    new_dest_nodes);
+	      if (BE (err != REG_NOERROR, 0))
+		{
+		  re_node_set_free (&dest_nodes);
+		  goto free_return;
+		}
+	      mctx->state_log[dest_str_idx]
+		= re_acquire_state_context (&err, dfa, &dest_nodes, context);
+	      re_node_set_free (&dest_nodes);
+	      if (BE (mctx->state_log[dest_str_idx] == NULL
+		      && err != REG_NOERROR, 0))
+		goto free_return;
+	    }
+	  /* We need to check recursively if the backreference can epsilon
+	     transit.  */
+	  if (subexp_len == 0
+	      && mctx->state_log[cur_str_idx]->nodes.nelem > prev_nelem)
+	    {
+	      err = check_subexp_matching_top (mctx, new_dest_nodes,
+					       cur_str_idx);
+	      if (BE (err != REG_NOERROR, 0))
+		goto free_return;
+	      err = transit_state_bkref (mctx, new_dest_nodes);
+	      if (BE (err != REG_NOERROR, 0))
+		goto free_return;
+	    }
+	}
+    }
+  err = REG_NOERROR;
+ free_return:
+  return err;
+}
+
+/* Enumerate all the candidates which the backreference BKREF_NODE can match
+   at BKREF_STR_IDX, and register them by match_ctx_add_entry().
+   Note that we might collect inappropriate candidates here.
+   However, the cost of checking them strictly here is too high, then we
+   delay these checking for prune_impossible_nodes().  */
+
+static reg_errcode_t
+internal_function
+get_subexp (re_match_context_t *mctx, int bkref_node, int bkref_str_idx)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int subexp_num, sub_top_idx;
+  const char *buf = (const char *) re_string_get_buffer (&mctx->input);
+  /* Return if we have already checked BKREF_NODE at BKREF_STR_IDX.  */
+  int cache_idx = search_cur_bkref_entry (mctx, bkref_str_idx);
+  if (cache_idx != -1)
+    {
+      const struct re_backref_cache_entry *entry
+	= mctx->bkref_ents + cache_idx;
+      do
+        if (entry->node == bkref_node)
+	  return REG_NOERROR; /* We already checked it.  */
+      while (entry++->more);
+    }
+
+  subexp_num = dfa->nodes[bkref_node].opr.idx;
+
+  /* For each sub expression  */
+  for (sub_top_idx = 0; sub_top_idx < mctx->nsub_tops; ++sub_top_idx)
+    {
+      reg_errcode_t err;
+      re_sub_match_top_t *sub_top = mctx->sub_tops[sub_top_idx];
+      re_sub_match_last_t *sub_last;
+      int sub_last_idx, sl_str, bkref_str_off;
+
+      if (dfa->nodes[sub_top->node].opr.idx != subexp_num)
+	continue; /* It isn't related.  */
+
+      sl_str = sub_top->str_idx;
+      bkref_str_off = bkref_str_idx;
+      /* At first, check the last node of sub expressions we already
+	 evaluated.  */
+      for (sub_last_idx = 0; sub_last_idx < sub_top->nlasts; ++sub_last_idx)
+	{
+	  int sl_str_diff;
+	  sub_last = sub_top->lasts[sub_last_idx];
+	  sl_str_diff = sub_last->str_idx - sl_str;
+	  /* The matched string by the sub expression match with the substring
+	     at the back reference?  */
+	  if (sl_str_diff > 0)
+	    {
+	      if (BE (bkref_str_off + sl_str_diff > mctx->input.valid_len, 0))
+		{
+		  /* Not enough chars for a successful match.  */
+		  if (bkref_str_off + sl_str_diff > mctx->input.len)
+		    break;
+
+		  err = clean_state_log_if_needed (mctx,
+						   bkref_str_off
+						   + sl_str_diff);
+		  if (BE (err != REG_NOERROR, 0))
+		    return err;
+		  buf = (const char *) re_string_get_buffer (&mctx->input);
+		}
+	      if (memcmp (buf + bkref_str_off, buf + sl_str, sl_str_diff) != 0)
+		/* We don't need to search this sub expression any more.  */
+		break;
+	    }
+	  bkref_str_off += sl_str_diff;
+	  sl_str += sl_str_diff;
+	  err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
+				bkref_str_idx);
+
+	  /* Reload buf, since the preceding call might have reallocated
+	     the buffer.  */
+	  buf = (const char *) re_string_get_buffer (&mctx->input);
+
+	  if (err == REG_NOMATCH)
+	    continue;
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+	}
+
+      if (sub_last_idx < sub_top->nlasts)
+	continue;
+      if (sub_last_idx > 0)
+	++sl_str;
+      /* Then, search for the other last nodes of the sub expression.  */
+      for (; sl_str <= bkref_str_idx; ++sl_str)
+	{
+	  int cls_node, sl_str_off;
+	  const re_node_set *nodes;
+	  sl_str_off = sl_str - sub_top->str_idx;
+	  /* The matched string by the sub expression match with the substring
+	     at the back reference?  */
+	  if (sl_str_off > 0)
+	    {
+	      if (BE (bkref_str_off >= mctx->input.valid_len, 0))
+		{
+		  /* If we are at the end of the input, we cannot match.  */
+		  if (bkref_str_off >= mctx->input.len)
+		    break;
+
+		  err = extend_buffers (mctx);
+		  if (BE (err != REG_NOERROR, 0))
+		    return err;
+
+		  buf = (const char *) re_string_get_buffer (&mctx->input);
+		}
+	      if (buf [bkref_str_off++] != buf[sl_str - 1])
+		break; /* We don't need to search this sub expression
+			  any more.  */
+	    }
+	  if (mctx->state_log[sl_str] == NULL)
+	    continue;
+	  /* Does this state have a ')' of the sub expression?  */
+	  nodes = &mctx->state_log[sl_str]->nodes;
+	  cls_node = find_subexp_node (dfa, nodes, subexp_num,
+				       OP_CLOSE_SUBEXP);
+	  if (cls_node == -1)
+	    continue; /* No.  */
+	  if (sub_top->path == NULL)
+	    {
+	      sub_top->path = calloc (sizeof (state_array_t),
+				      sl_str - sub_top->str_idx + 1);
+	      if (sub_top->path == NULL)
+		return REG_ESPACE;
+	    }
+	  /* Can the OP_OPEN_SUBEXP node arrive the OP_CLOSE_SUBEXP node
+	     in the current context?  */
+	  err = check_arrival (mctx, sub_top->path, sub_top->node,
+			       sub_top->str_idx, cls_node, sl_str,
+			       OP_CLOSE_SUBEXP);
+	  if (err == REG_NOMATCH)
+	      continue;
+	  if (BE (err != REG_NOERROR, 0))
+	      return err;
+	  sub_last = match_ctx_add_sublast (sub_top, cls_node, sl_str);
+	  if (BE (sub_last == NULL, 0))
+	    return REG_ESPACE;
+	  err = get_subexp_sub (mctx, sub_top, sub_last, bkref_node,
+				bkref_str_idx);
+	  if (err == REG_NOMATCH)
+	    continue;
+	}
+    }
+  return REG_NOERROR;
+}
+
+/* Helper functions for get_subexp().  */
+
+/* Check SUB_LAST can arrive to the back reference BKREF_NODE at BKREF_STR.
+   If it can arrive, register the sub expression expressed with SUB_TOP
+   and SUB_LAST.  */
+
+static reg_errcode_t
+internal_function
+get_subexp_sub (re_match_context_t *mctx, const re_sub_match_top_t *sub_top,
+		re_sub_match_last_t *sub_last, int bkref_node, int bkref_str)
+{
+  reg_errcode_t err;
+  int to_idx;
+  /* Can the subexpression arrive the back reference?  */
+  err = check_arrival (mctx, &sub_last->path, sub_last->node,
+		       sub_last->str_idx, bkref_node, bkref_str,
+		       OP_OPEN_SUBEXP);
+  if (err != REG_NOERROR)
+    return err;
+  err = match_ctx_add_entry (mctx, bkref_node, bkref_str, sub_top->str_idx,
+			     sub_last->str_idx);
+  if (BE (err != REG_NOERROR, 0))
+    return err;
+  to_idx = bkref_str + sub_last->str_idx - sub_top->str_idx;
+  return clean_state_log_if_needed (mctx, to_idx);
+}
+
+/* Find the first node which is '(' or ')' and whose index is SUBEXP_IDX.
+   Search '(' if FL_OPEN, or search ')' otherwise.
+   TODO: This function isn't efficient...
+	 Because there might be more than one nodes whose types are
+	 OP_OPEN_SUBEXP and whose index is SUBEXP_IDX, we must check all
+	 nodes.
+	 E.g. RE: (a){2}  */
+
+static int
+internal_function
+find_subexp_node (const re_dfa_t *dfa, const re_node_set *nodes,
+		  int subexp_idx, int type)
+{
+  int cls_idx;
+  for (cls_idx = 0; cls_idx < nodes->nelem; ++cls_idx)
+    {
+      int cls_node = nodes->elems[cls_idx];
+      const re_token_t *node = dfa->nodes + cls_node;
+      if (node->type == type
+	  && node->opr.idx == subexp_idx)
+	return cls_node;
+    }
+  return -1;
+}
+
+/* Check whether the node TOP_NODE at TOP_STR can arrive to the node
+   LAST_NODE at LAST_STR.  We record the path onto PATH since it will be
+   heavily reused.
+   Return REG_NOERROR if it can arrive, or REG_NOMATCH otherwise.  */
+
+static reg_errcode_t
+internal_function
+check_arrival (re_match_context_t *mctx, state_array_t *path, int top_node,
+	       int top_str, int last_node, int last_str, int type)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  reg_errcode_t err = REG_NOERROR;
+  int subexp_num, backup_cur_idx, str_idx, null_cnt;
+  re_dfastate_t *cur_state = NULL;
+  re_node_set *cur_nodes, next_nodes;
+  re_dfastate_t **backup_state_log;
+  unsigned int context;
+
+  subexp_num = dfa->nodes[top_node].opr.idx;
+  /* Extend the buffer if we need.  */
+  if (BE (path->alloc < last_str + mctx->max_mb_elem_len + 1, 0))
+    {
+      re_dfastate_t **new_array;
+      int old_alloc = path->alloc;
+      path->alloc += last_str + mctx->max_mb_elem_len + 1;
+      new_array = re_realloc (path->array, re_dfastate_t *, path->alloc);
+      if (BE (new_array == NULL, 0))
+	{
+	  path->alloc = old_alloc;
+	  return REG_ESPACE;
+	}
+      path->array = new_array;
+      memset (new_array + old_alloc, '\0',
+	      sizeof (re_dfastate_t *) * (path->alloc - old_alloc));
+    }
+
+  str_idx = path->next_idx ?: top_str;
+
+  /* Temporary modify MCTX.  */
+  backup_state_log = mctx->state_log;
+  backup_cur_idx = mctx->input.cur_idx;
+  mctx->state_log = path->array;
+  mctx->input.cur_idx = str_idx;
+
+  /* Setup initial node set.  */
+  context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
+  if (str_idx == top_str)
+    {
+      err = re_node_set_init_1 (&next_nodes, top_node);
+      if (BE (err != REG_NOERROR, 0))
+	return err;
+      err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
+      if (BE (err != REG_NOERROR, 0))
+	{
+	  re_node_set_free (&next_nodes);
+	  return err;
+	}
+    }
+  else
+    {
+      cur_state = mctx->state_log[str_idx];
+      if (cur_state && cur_state->has_backref)
+	{
+	  err = re_node_set_init_copy (&next_nodes, &cur_state->nodes);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+	}
+      else
+	re_node_set_init_empty (&next_nodes);
+    }
+  if (str_idx == top_str || (cur_state && cur_state->has_backref))
+    {
+      if (next_nodes.nelem)
+	{
+	  err = expand_bkref_cache (mctx, &next_nodes, str_idx,
+				    subexp_num, type);
+	  if (BE (err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&next_nodes);
+	      return err;
+	    }
+	}
+      cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
+      if (BE (cur_state == NULL && err != REG_NOERROR, 0))
+	{
+	  re_node_set_free (&next_nodes);
+	  return err;
+	}
+      mctx->state_log[str_idx] = cur_state;
+    }
+
+  for (null_cnt = 0; str_idx < last_str && null_cnt <= mctx->max_mb_elem_len;)
+    {
+      re_node_set_empty (&next_nodes);
+      if (mctx->state_log[str_idx + 1])
+	{
+	  err = re_node_set_merge (&next_nodes,
+				   &mctx->state_log[str_idx + 1]->nodes);
+	  if (BE (err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&next_nodes);
+	      return err;
+	    }
+	}
+      if (cur_state)
+	{
+	  err = check_arrival_add_next_nodes (mctx, str_idx,
+					      &cur_state->non_eps_nodes,
+					      &next_nodes);
+	  if (BE (err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&next_nodes);
+	      return err;
+	    }
+	}
+      ++str_idx;
+      if (next_nodes.nelem)
+	{
+	  err = check_arrival_expand_ecl (dfa, &next_nodes, subexp_num, type);
+	  if (BE (err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&next_nodes);
+	      return err;
+	    }
+	  err = expand_bkref_cache (mctx, &next_nodes, str_idx,
+				    subexp_num, type);
+	  if (BE (err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&next_nodes);
+	      return err;
+	    }
+	}
+      context = re_string_context_at (&mctx->input, str_idx - 1, mctx->eflags);
+      cur_state = re_acquire_state_context (&err, dfa, &next_nodes, context);
+      if (BE (cur_state == NULL && err != REG_NOERROR, 0))
+	{
+	  re_node_set_free (&next_nodes);
+	  return err;
+	}
+      mctx->state_log[str_idx] = cur_state;
+      null_cnt = cur_state == NULL ? null_cnt + 1 : 0;
+    }
+  re_node_set_free (&next_nodes);
+  cur_nodes = (mctx->state_log[last_str] == NULL ? NULL
+	       : &mctx->state_log[last_str]->nodes);
+  path->next_idx = str_idx;
+
+  /* Fix MCTX.  */
+  mctx->state_log = backup_state_log;
+  mctx->input.cur_idx = backup_cur_idx;
+
+  /* Then check the current node set has the node LAST_NODE.  */
+  if (cur_nodes != NULL && re_node_set_contains (cur_nodes, last_node))
+    return REG_NOERROR;
+
+  return REG_NOMATCH;
+}
+
+/* Helper functions for check_arrival.  */
+
+/* Calculate the destination nodes of CUR_NODES at STR_IDX, and append them
+   to NEXT_NODES.
+   TODO: This function is similar to the functions transit_state*(),
+	 however this function has many additional works.
+	 Can't we unify them?  */
+
+static reg_errcode_t
+internal_function
+check_arrival_add_next_nodes (re_match_context_t *mctx, int str_idx,
+			      re_node_set *cur_nodes, re_node_set *next_nodes)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  int result;
+  int cur_idx;
+  reg_errcode_t err = REG_NOERROR;
+  re_node_set union_set;
+  re_node_set_init_empty (&union_set);
+  for (cur_idx = 0; cur_idx < cur_nodes->nelem; ++cur_idx)
+    {
+      int naccepted = 0;
+      int cur_node = cur_nodes->elems[cur_idx];
+#ifdef DEBUG
+      re_token_type_t type = dfa->nodes[cur_node].type;
+      assert (!IS_EPSILON_NODE (type));
+#endif
+#ifdef RE_ENABLE_I18N
+      /* If the node may accept `multi byte'.  */
+      if (dfa->nodes[cur_node].accept_mb)
+	{
+	  naccepted = check_node_accept_bytes (dfa, cur_node, &mctx->input,
+					       str_idx);
+	  if (naccepted > 1)
+	    {
+	      re_dfastate_t *dest_state;
+	      int next_node = dfa->nexts[cur_node];
+	      int next_idx = str_idx + naccepted;
+	      dest_state = mctx->state_log[next_idx];
+	      re_node_set_empty (&union_set);
+	      if (dest_state)
+		{
+		  err = re_node_set_merge (&union_set, &dest_state->nodes);
+		  if (BE (err != REG_NOERROR, 0))
+		    {
+		      re_node_set_free (&union_set);
+		      return err;
+		    }
+		}
+	      result = re_node_set_insert (&union_set, next_node);
+	      if (BE (result < 0, 0))
+		{
+		  re_node_set_free (&union_set);
+		  return REG_ESPACE;
+		}
+	      mctx->state_log[next_idx] = re_acquire_state (&err, dfa,
+							    &union_set);
+	      if (BE (mctx->state_log[next_idx] == NULL
+		      && err != REG_NOERROR, 0))
+		{
+		  re_node_set_free (&union_set);
+		  return err;
+		}
+	    }
+	}
+#endif /* RE_ENABLE_I18N */
+      if (naccepted
+	  || check_node_accept (mctx, dfa->nodes + cur_node, str_idx))
+	{
+	  result = re_node_set_insert (next_nodes, dfa->nexts[cur_node]);
+	  if (BE (result < 0, 0))
+	    {
+	      re_node_set_free (&union_set);
+	      return REG_ESPACE;
+	    }
+	}
+    }
+  re_node_set_free (&union_set);
+  return REG_NOERROR;
+}
+
+/* For all the nodes in CUR_NODES, add the epsilon closures of them to
+   CUR_NODES, however exclude the nodes which are:
+    - inside the sub expression whose number is EX_SUBEXP, if FL_OPEN.
+    - out of the sub expression whose number is EX_SUBEXP, if !FL_OPEN.
+*/
+
+static reg_errcode_t
+internal_function
+check_arrival_expand_ecl (const re_dfa_t *dfa, re_node_set *cur_nodes,
+			  int ex_subexp, int type)
+{
+  reg_errcode_t err;
+  int idx, outside_node;
+  re_node_set new_nodes;
+#ifdef DEBUG
+  assert (cur_nodes->nelem);
+#endif
+  err = re_node_set_alloc (&new_nodes, cur_nodes->nelem);
+  if (BE (err != REG_NOERROR, 0))
+    return err;
+  /* Create a new node set NEW_NODES with the nodes which are epsilon
+     closures of the node in CUR_NODES.  */
+
+  for (idx = 0; idx < cur_nodes->nelem; ++idx)
+    {
+      int cur_node = cur_nodes->elems[idx];
+      const re_node_set *eclosure = dfa->eclosures + cur_node;
+      outside_node = find_subexp_node (dfa, eclosure, ex_subexp, type);
+      if (outside_node == -1)
+	{
+	  /* There are no problematic nodes, just merge them.  */
+	  err = re_node_set_merge (&new_nodes, eclosure);
+	  if (BE (err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&new_nodes);
+	      return err;
+	    }
+	}
+      else
+	{
+	  /* There are problematic nodes, re-calculate incrementally.  */
+	  err = check_arrival_expand_ecl_sub (dfa, &new_nodes, cur_node,
+					      ex_subexp, type);
+	  if (BE (err != REG_NOERROR, 0))
+	    {
+	      re_node_set_free (&new_nodes);
+	      return err;
+	    }
+	}
+    }
+  re_node_set_free (cur_nodes);
+  *cur_nodes = new_nodes;
+  return REG_NOERROR;
+}
+
+/* Helper function for check_arrival_expand_ecl.
+   Check incrementally the epsilon closure of TARGET, and if it isn't
+   problematic append it to DST_NODES.  */
+
+static reg_errcode_t
+internal_function
+check_arrival_expand_ecl_sub (const re_dfa_t *dfa, re_node_set *dst_nodes,
+			      int target, int ex_subexp, int type)
+{
+  int cur_node;
+  for (cur_node = target; !re_node_set_contains (dst_nodes, cur_node);)
+    {
+      int err;
+
+      if (dfa->nodes[cur_node].type == type
+	  && dfa->nodes[cur_node].opr.idx == ex_subexp)
+	{
+	  if (type == OP_CLOSE_SUBEXP)
+	    {
+	      err = re_node_set_insert (dst_nodes, cur_node);
+	      if (BE (err == -1, 0))
+		return REG_ESPACE;
+	    }
+	  break;
+	}
+      err = re_node_set_insert (dst_nodes, cur_node);
+      if (BE (err == -1, 0))
+	return REG_ESPACE;
+      if (dfa->edests[cur_node].nelem == 0)
+	break;
+      if (dfa->edests[cur_node].nelem == 2)
+	{
+	  err = check_arrival_expand_ecl_sub (dfa, dst_nodes,
+					      dfa->edests[cur_node].elems[1],
+					      ex_subexp, type);
+	  if (BE (err != REG_NOERROR, 0))
+	    return err;
+	}
+      cur_node = dfa->edests[cur_node].elems[0];
+    }
+  return REG_NOERROR;
+}
+
+
+/* For all the back references in the current state, calculate the
+   destination of the back references by the appropriate entry
+   in MCTX->BKREF_ENTS.  */
+
+static reg_errcode_t
+internal_function
+expand_bkref_cache (re_match_context_t *mctx, re_node_set *cur_nodes,
+		    int cur_str, int subexp_num, int type)
+{
+  const re_dfa_t *const dfa = mctx->dfa;
+  reg_errcode_t err;
+  int cache_idx_start = search_cur_bkref_entry (mctx, cur_str);
+  struct re_backref_cache_entry *ent;
+
+  if (cache_idx_start == -1)
+    return REG_NOERROR;
+
+ restart:
+  ent = mctx->bkref_ents + cache_idx_start;
+  do
+    {
+      int to_idx, next_node;
+
+      /* Is this entry ENT is appropriate?  */
+      if (!re_node_set_contains (cur_nodes, ent->node))
+	continue; /* No.  */
+
+      to_idx = cur_str + ent->subexp_to - ent->subexp_from;
+      /* Calculate the destination of the back reference, and append it
+	 to MCTX->STATE_LOG.  */
+      if (to_idx == cur_str)
+	{
+	  /* The backreference did epsilon transit, we must re-check all the
+	     node in the current state.  */
+	  re_node_set new_dests;
+	  reg_errcode_t err2, err3;
+	  next_node = dfa->edests[ent->node].elems[0];
+	  if (re_node_set_contains (cur_nodes, next_node))
+	    continue;
+	  err = re_node_set_init_1 (&new_dests, next_node);
+	  err2 = check_arrival_expand_ecl (dfa, &new_dests, subexp_num, type);
+	  err3 = re_node_set_merge (cur_nodes, &new_dests);
+	  re_node_set_free (&new_dests);
+	  if (BE (err != REG_NOERROR || err2 != REG_NOERROR
+		  || err3 != REG_NOERROR, 0))
+	    {
+	      err = (err != REG_NOERROR ? err
+		     : (err2 != REG_NOERROR ? err2 : err3));
+	      return err;
+	    }
+	  /* TODO: It is still inefficient...  */
+	  goto restart;
+	}
+      else
+	{
+	  re_node_set union_set;
+	  next_node = dfa->nexts[ent->node];
+	  if (mctx->state_log[to_idx])
+	    {
+	      int ret;
+	      if (re_node_set_contains (&mctx->state_log[to_idx]->nodes,
+					next_node))
+		continue;
+	      err = re_node_set_init_copy (&union_set,
+					   &mctx->state_log[to_idx]->nodes);
+	      ret = re_node_set_insert (&union_set, next_node);
+	      if (BE (err != REG_NOERROR || ret < 0, 0))
+		{
+		  re_node_set_free (&union_set);
+		  err = err != REG_NOERROR ? err : REG_ESPACE;
+		  return err;
+		}
+	    }
+	  else
+	    {
+	      err = re_node_set_init_1 (&union_set, next_node);
+	      if (BE (err != REG_NOERROR, 0))
+		return err;
+	    }
+	  mctx->state_log[to_idx] = re_acquire_state (&err, dfa, &union_set);
+	  re_node_set_free (&union_set);
+	  if (BE (mctx->state_log[to_idx] == NULL
+		  && err != REG_NOERROR, 0))
+	    return err;
+	}
+    }
+  while (ent++->more);
+  return REG_NOERROR;
+}
+
+/* Build transition table for the state.
+   Return 1 if succeeded, otherwise return NULL.  */
+
+static int
+internal_function
+build_trtable (const re_dfa_t *dfa, re_dfastate_t *state)
+{
+  reg_errcode_t err;
+  int i, j, ch, need_word_trtable = 0;
+  bitset_word_t elem, mask;
+  bool dests_node_malloced = false;
+  bool dest_states_malloced = false;
+  int ndests; /* Number of the destination states from `state'.  */
+  re_dfastate_t **trtable;
+  re_dfastate_t **dest_states = NULL, **dest_states_word, **dest_states_nl;
+  re_node_set follows, *dests_node;
+  bitset_t *dests_ch;
+  bitset_t acceptable;
+
+  struct dests_alloc
+  {
+    re_node_set dests_node[SBC_MAX];
+    bitset_t dests_ch[SBC_MAX];
+  } *dests_alloc;
+
+  /* We build DFA states which corresponds to the destination nodes
+     from `state'.  `dests_node[i]' represents the nodes which i-th
+     destination state contains, and `dests_ch[i]' represents the
+     characters which i-th destination state accepts.  */
+  if (__libc_use_alloca (sizeof (struct dests_alloc)))
+    dests_alloc = (struct dests_alloc *) alloca (sizeof (struct dests_alloc));
+  else
+    {
+      dests_alloc = re_malloc (struct dests_alloc, 1);
+      if (BE (dests_alloc == NULL, 0))
+	return 0;
+      dests_node_malloced = true;
+    }
+  dests_node = dests_alloc->dests_node;
+  dests_ch = dests_alloc->dests_ch;
+
+  /* Initialize transiton table.  */
+  state->word_trtable = state->trtable = NULL;
+
+  /* At first, group all nodes belonging to `state' into several
+     destinations.  */
+  ndests = group_nodes_into_DFAstates (dfa, state, dests_node, dests_ch);
+  if (BE (ndests <= 0, 0))
+    {
+      if (dests_node_malloced)
+	free (dests_alloc);
+      /* Return 0 in case of an error, 1 otherwise.  */
+      if (ndests == 0)
+	{
+	  state->trtable = (re_dfastate_t **)
+	    calloc (sizeof (re_dfastate_t *), SBC_MAX);
+	  return 1;
+	}
+      return 0;
+    }
+
+  err = re_node_set_alloc (&follows, ndests + 1);
+  if (BE (err != REG_NOERROR, 0))
+    goto out_free;
+
+  if (__libc_use_alloca ((sizeof (re_node_set) + sizeof (bitset_t)) * SBC_MAX
+			 + ndests * 3 * sizeof (re_dfastate_t *)))
+    dest_states = (re_dfastate_t **)
+      alloca (ndests * 3 * sizeof (re_dfastate_t *));
+  else
+    {
+      dest_states = (re_dfastate_t **)
+	malloc (ndests * 3 * sizeof (re_dfastate_t *));
+      if (BE (dest_states == NULL, 0))
+	{
+out_free:
+	  if (dest_states_malloced)
+	    free (dest_states);
+	  re_node_set_free (&follows);
+	  for (i = 0; i < ndests; ++i)
+	    re_node_set_free (dests_node + i);
+	  if (dests_node_malloced)
+	    free (dests_alloc);
+	  return 0;
+	}
+      dest_states_malloced = true;
+    }
+  dest_states_word = dest_states + ndests;
+  dest_states_nl = dest_states_word + ndests;
+  bitset_empty (acceptable);
+
+  /* Then build the states for all destinations.  */
+  for (i = 0; i < ndests; ++i)
+    {
+      int next_node;
+      re_node_set_empty (&follows);
+      /* Merge the follows of this destination states.  */
+      for (j = 0; j < dests_node[i].nelem; ++j)
+	{
+	  next_node = dfa->nexts[dests_node[i].elems[j]];
+	  if (next_node != -1)
+	    {
+	      err = re_node_set_merge (&follows, dfa->eclosures + next_node);
+	      if (BE (err != REG_NOERROR, 0))
+		goto out_free;
+	    }
+	}
+      dest_states[i] = re_acquire_state_context (&err, dfa, &follows, 0);
+      if (BE (dest_states[i] == NULL && err != REG_NOERROR, 0))
+	goto out_free;
+      /* If the new state has context constraint,
+	 build appropriate states for these contexts.  */
+      if (dest_states[i]->has_constraint)
+	{
+	  dest_states_word[i] = re_acquire_state_context (&err, dfa, &follows,
+							  CONTEXT_WORD);
+	  if (BE (dest_states_word[i] == NULL && err != REG_NOERROR, 0))
+	    goto out_free;
+
+	  if (dest_states[i] != dest_states_word[i] && dfa->mb_cur_max > 1)
+	    need_word_trtable = 1;
+
+	  dest_states_nl[i] = re_acquire_state_context (&err, dfa, &follows,
+							CONTEXT_NEWLINE);
+	  if (BE (dest_states_nl[i] == NULL && err != REG_NOERROR, 0))
+	    goto out_free;
+ 	}
+      else
+	{
+	  dest_states_word[i] = dest_states[i];
+	  dest_states_nl[i] = dest_states[i];
+	}
+      bitset_merge (acceptable, dests_ch[i]);
+    }
+
+  if (!BE (need_word_trtable, 0))
+    {
+      /* We don't care about whether the following character is a word
+	 character, or we are in a single-byte character set so we can
+	 discern by looking at the character code: allocate a
+	 256-entry transition table.  */
+      trtable = state->trtable =
+	(re_dfastate_t **) calloc (sizeof (re_dfastate_t *), SBC_MAX);
+      if (BE (trtable == NULL, 0))
+	goto out_free;
+
+      /* For all characters ch...:  */
+      for (i = 0; i < BITSET_WORDS; ++i)
+	for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1;
+	     elem;
+	     mask <<= 1, elem >>= 1, ++ch)
+	  if (BE (elem & 1, 0))
+	    {
+	      /* There must be exactly one destination which accepts
+		 character ch.  See group_nodes_into_DFAstates.  */
+	      for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
+		;
+
+	      /* j-th destination accepts the word character ch.  */
+	      if (dfa->word_char[i] & mask)
+		trtable[ch] = dest_states_word[j];
+	      else
+		trtable[ch] = dest_states[j];
+	    }
+    }
+  else
+    {
+      /* We care about whether the following character is a word
+	 character, and we are in a multi-byte character set: discern
+	 by looking at the character code: build two 256-entry
+	 transition tables, one starting at trtable[0] and one
+	 starting at trtable[SBC_MAX].  */
+      trtable = state->word_trtable =
+	(re_dfastate_t **) calloc (sizeof (re_dfastate_t *), 2 * SBC_MAX);
+      if (BE (trtable == NULL, 0))
+	goto out_free;
+
+      /* For all characters ch...:  */
+      for (i = 0; i < BITSET_WORDS; ++i)
+	for (ch = i * BITSET_WORD_BITS, elem = acceptable[i], mask = 1;
+	     elem;
+	     mask <<= 1, elem >>= 1, ++ch)
+	  if (BE (elem & 1, 0))
+	    {
+	      /* There must be exactly one destination which accepts
+		 character ch.  See group_nodes_into_DFAstates.  */
+	      for (j = 0; (dests_ch[j][i] & mask) == 0; ++j)
+		;
+
+	      /* j-th destination accepts the word character ch.  */
+	      trtable[ch] = dest_states[j];
+	      trtable[ch + SBC_MAX] = dest_states_word[j];
+	    }
+    }
+
+  /* new line */
+  if (bitset_contain (acceptable, NEWLINE_CHAR))
+    {
+      /* The current state accepts newline character.  */
+      for (j = 0; j < ndests; ++j)
+	if (bitset_contain (dests_ch[j], NEWLINE_CHAR))
+	  {
+	    /* k-th destination accepts newline character.  */
+	    trtable[NEWLINE_CHAR] = dest_states_nl[j];
+	    if (need_word_trtable)
+	      trtable[NEWLINE_CHAR + SBC_MAX] = dest_states_nl[j];
+	    /* There must be only one destination which accepts
+	       newline.  See group_nodes_into_DFAstates.  */
+	    break;
+	  }
+    }
+
+  if (dest_states_malloced)
+    free (dest_states);
+
+  re_node_set_free (&follows);
+  for (i = 0; i < ndests; ++i)
+    re_node_set_free (dests_node + i);
+
+  if (dests_node_malloced)
+    free (dests_alloc);
+
+  return 1;
+}
+
+/* Group all nodes belonging to STATE into several destinations.
+   Then for all destinations, set the nodes belonging to the destination
+   to DESTS_NODE[i] and set the characters accepted by the destination
+   to DEST_CH[i].  This function return the number of destinations.  */
+
+static int
+internal_function
+group_nodes_into_DFAstates (const re_dfa_t *dfa, const re_dfastate_t *state,
+			    re_node_set *dests_node, bitset_t *dests_ch)
+{
+  reg_errcode_t err;
+  int result;
+  int i, j, k;
+  int ndests; /* Number of the destinations from `state'.  */
+  bitset_t accepts; /* Characters a node can accept.  */
+  const re_node_set *cur_nodes = &state->nodes;
+  bitset_empty (accepts);
+  ndests = 0;
+
+  /* For all the nodes belonging to `state',  */
+  for (i = 0; i < cur_nodes->nelem; ++i)
+    {
+      re_token_t *node = &dfa->nodes[cur_nodes->elems[i]];
+      re_token_type_t type = node->type;
+      unsigned int constraint = node->constraint;
+
+      /* Enumerate all single byte character this node can accept.  */
+      if (type == CHARACTER)
+	bitset_set (accepts, node->opr.c);
+      else if (type == SIMPLE_BRACKET)
+	{
+	  bitset_merge (accepts, node->opr.sbcset);
+	}
+      else if (type == OP_PERIOD)
+	{
+#ifdef RE_ENABLE_I18N
+	  if (dfa->mb_cur_max > 1)
+	    bitset_merge (accepts, dfa->sb_char);
+	  else
+#endif
+	    bitset_set_all (accepts);
+	  if (!(dfa->syntax & RE_DOT_NEWLINE))
+	    bitset_clear (accepts, '\n');
+	  if (dfa->syntax & RE_DOT_NOT_NULL)
+	    bitset_clear (accepts, '\0');
+	}
+#ifdef RE_ENABLE_I18N
+      else if (type == OP_UTF8_PERIOD)
+        {
+	  memset (accepts, '\xff', sizeof (bitset_t) / 2);
+	  if (!(dfa->syntax & RE_DOT_NEWLINE))
+	    bitset_clear (accepts, '\n');
+	  if (dfa->syntax & RE_DOT_NOT_NULL)
+	    bitset_clear (accepts, '\0');
+        }
+#endif
+      else
+	continue;
+
+      /* Check the `accepts' and sift the characters which are not
+	 match it the context.  */
+      if (constraint)
+	{
+	  if (constraint & NEXT_NEWLINE_CONSTRAINT)
+	    {
+	      bool accepts_newline = bitset_contain (accepts, NEWLINE_CHAR);
+	      bitset_empty (accepts);
+	      if (accepts_newline)
+		bitset_set (accepts, NEWLINE_CHAR);
+	      else
+		continue;
+	    }
+	  if (constraint & NEXT_ENDBUF_CONSTRAINT)
+	    {
+	      bitset_empty (accepts);
+	      continue;
+	    }
+
+	  if (constraint & NEXT_WORD_CONSTRAINT)
+	    {
+	      bitset_word_t any_set = 0;
+	      if (type == CHARACTER && !node->word_char)
+		{
+		  bitset_empty (accepts);
+		  continue;
+		}
+#ifdef RE_ENABLE_I18N
+	      if (dfa->mb_cur_max > 1)
+		for (j = 0; j < BITSET_WORDS; ++j)
+		  any_set |= (accepts[j] &= (dfa->word_char[j] | ~dfa->sb_char[j]));
+	      else
+#endif
+		for (j = 0; j < BITSET_WORDS; ++j)
+		  any_set |= (accepts[j] &= dfa->word_char[j]);
+	      if (!any_set)
+		continue;
+	    }
+	  if (constraint & NEXT_NOTWORD_CONSTRAINT)
+	    {
+	      bitset_word_t any_set = 0;
+	      if (type == CHARACTER && node->word_char)
+		{
+		  bitset_empty (accepts);
+		  continue;
+		}
+#ifdef RE_ENABLE_I18N
+	      if (dfa->mb_cur_max > 1)
+		for (j = 0; j < BITSET_WORDS; ++j)
+		  any_set |= (accepts[j] &= ~(dfa->word_char[j] & dfa->sb_char[j]));
+	      else
+#endif
+		for (j = 0; j < BITSET_WORDS; ++j)
+		  any_set |= (accepts[j] &= ~dfa->word_char[j]);
+	      if (!any_set)
+		continue;
+	    }
+	}
+
+      /* Then divide `accepts' into DFA states, or create a new
+	 state.  Above, we make sure that accepts is not empty.  */
+      for (j = 0; j < ndests; ++j)
+	{
+	  bitset_t intersec; /* Intersection sets, see below.  */
+	  bitset_t remains;
+	  /* Flags, see below.  */
+	  bitset_word_t has_intersec, not_subset, not_consumed;
+
+	  /* Optimization, skip if this state doesn't accept the character.  */
+	  if (type == CHARACTER && !bitset_contain (dests_ch[j], node->opr.c))
+	    continue;
+
+	  /* Enumerate the intersection set of this state and `accepts'.  */
+	  has_intersec = 0;
+	  for (k = 0; k < BITSET_WORDS; ++k)
+	    has_intersec |= intersec[k] = accepts[k] & dests_ch[j][k];
+	  /* And skip if the intersection set is empty.  */
+	  if (!has_intersec)
+	    continue;
+
+	  /* Then check if this state is a subset of `accepts'.  */
+	  not_subset = not_consumed = 0;
+	  for (k = 0; k < BITSET_WORDS; ++k)
+	    {
+	      not_subset |= remains[k] = ~accepts[k] & dests_ch[j][k];
+	      not_consumed |= accepts[k] = accepts[k] & ~dests_ch[j][k];
+	    }
+
+	  /* If this state isn't a subset of `accepts', create a
+	     new group state, which has the `remains'. */
+	  if (not_subset)
+	    {
+	      bitset_copy (dests_ch[ndests], remains);
+	      bitset_copy (dests_ch[j], intersec);
+	      err = re_node_set_init_copy (dests_node + ndests, &dests_node[j]);
+	      if (BE (err != REG_NOERROR, 0))
+		goto error_return;
+	      ++ndests;
+	    }
+
+	  /* Put the position in the current group. */
+	  result = re_node_set_insert (&dests_node[j], cur_nodes->elems[i]);
+	  if (BE (result < 0, 0))
+	    goto error_return;
+
+	  /* If all characters are consumed, go to next node. */
+	  if (!not_consumed)
+	    break;
+	}
+      /* Some characters remain, create a new group. */
+      if (j == ndests)
+	{
+	  bitset_copy (dests_ch[ndests], accepts);
+	  err = re_node_set_init_1 (dests_node + ndests, cur_nodes->elems[i]);
+	  if (BE (err != REG_NOERROR, 0))
+	    goto error_return;
+	  ++ndests;
+	  bitset_empty (accepts);
+	}
+    }
+  return ndests;
+ error_return:
+  for (j = 0; j < ndests; ++j)
+    re_node_set_free (dests_node + j);
+  return -1;
+}
+
+#ifdef RE_ENABLE_I18N
+/* Check how many bytes the node `dfa->nodes[node_idx]' accepts.
+   Return the number of the bytes the node accepts.
+   STR_IDX is the current index of the input string.
+
+   This function handles the nodes which can accept one character, or
+   one collating element like '.', '[a-z]', opposite to the other nodes
+   can only accept one byte.  */
+
+static int
+internal_function
+check_node_accept_bytes (const re_dfa_t *dfa, int node_idx,
+			 const re_string_t *input, int str_idx)
+{
+  const re_token_t *node = dfa->nodes + node_idx;
+  int char_len, elem_len;
+  int i;
+
+  if (BE (node->type == OP_UTF8_PERIOD, 0))
+    {
+      unsigned char c = re_string_byte_at (input, str_idx), d;
+      if (BE (c < 0xc2, 1))
+	return 0;
+
+      if (str_idx + 2 > input->len)
+	return 0;
+
+      d = re_string_byte_at (input, str_idx + 1);
+      if (c < 0xe0)
+	return (d < 0x80 || d > 0xbf) ? 0 : 2;
+      else if (c < 0xf0)
+	{
+	  char_len = 3;
+	  if (c == 0xe0 && d < 0xa0)
+	    return 0;
+	}
+      else if (c < 0xf8)
+	{
+	  char_len = 4;
+	  if (c == 0xf0 && d < 0x90)
+	    return 0;
+	}
+      else if (c < 0xfc)
+	{
+	  char_len = 5;
+	  if (c == 0xf8 && d < 0x88)
+	    return 0;
+	}
+      else if (c < 0xfe)
+	{
+	  char_len = 6;
+	  if (c == 0xfc && d < 0x84)
+	    return 0;
+	}
+      else
+	return 0;
+
+      if (str_idx + char_len > input->len)
+	return 0;
+
+      for (i = 1; i < char_len; ++i)
+	{
+	  d = re_string_byte_at (input, str_idx + i);
+	  if (d < 0x80 || d > 0xbf)
+	    return 0;
+	}
+      return char_len;
+    }
+
+  char_len = re_string_char_size_at (input, str_idx);
+  if (node->type == OP_PERIOD)
+    {
+      if (char_len <= 1)
+        return 0;
+      /* FIXME: I don't think this if is needed, as both '\n'
+	 and '\0' are char_len == 1.  */
+      /* '.' accepts any one character except the following two cases.  */
+      if ((!(dfa->syntax & RE_DOT_NEWLINE) &&
+	   re_string_byte_at (input, str_idx) == '\n') ||
+	  ((dfa->syntax & RE_DOT_NOT_NULL) &&
+	   re_string_byte_at (input, str_idx) == '\0'))
+	return 0;
+      return char_len;
+    }
+
+  elem_len = re_string_elem_size_at (input, str_idx);
+  if ((elem_len <= 1 && char_len <= 1) || char_len == 0)
+    return 0;
+
+  if (node->type == COMPLEX_BRACKET)
+    {
+      const re_charset_t *cset = node->opr.mbcset;
+# ifdef _LIBC
+      const unsigned char *pin
+	= ((const unsigned char *) re_string_get_buffer (input) + str_idx);
+      int j;
+      uint32_t nrules;
+# endif /* _LIBC */
+      int match_len = 0;
+      wchar_t wc = ((cset->nranges || cset->nchar_classes || cset->nmbchars)
+		    ? re_string_wchar_at (input, str_idx) : 0);
+
+      /* match with multibyte character?  */
+      for (i = 0; i < cset->nmbchars; ++i)
+	if (wc == cset->mbchars[i])
+	  {
+	    match_len = char_len;
+	    goto check_node_accept_bytes_match;
+	  }
+      /* match with character_class?  */
+      for (i = 0; i < cset->nchar_classes; ++i)
+	{
+	  wctype_t wt = cset->char_classes[i];
+	  if (__iswctype (wc, wt))
+	    {
+	      match_len = char_len;
+	      goto check_node_accept_bytes_match;
+	    }
+	}
+
+# ifdef _LIBC
+      nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
+      if (nrules != 0)
+	{
+	  unsigned int in_collseq = 0;
+	  const int32_t *table, *indirect;
+	  const unsigned char *weights, *extra;
+	  const char *collseqwc;
+	  int32_t idx;
+	  /* This #include defines a local function!  */
+#  include <locale/weight.h>
+
+	  /* match with collating_symbol?  */
+	  if (cset->ncoll_syms)
+	    extra = (const unsigned char *)
+	      _NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
+	  for (i = 0; i < cset->ncoll_syms; ++i)
+	    {
+	      const unsigned char *coll_sym = extra + cset->coll_syms[i];
+	      /* Compare the length of input collating element and
+		 the length of current collating element.  */
+	      if (*coll_sym != elem_len)
+		continue;
+	      /* Compare each bytes.  */
+	      for (j = 0; j < *coll_sym; j++)
+		if (pin[j] != coll_sym[1 + j])
+		  break;
+	      if (j == *coll_sym)
+		{
+		  /* Match if every bytes is equal.  */
+		  match_len = j;
+		  goto check_node_accept_bytes_match;
+		}
+	    }
+
+	  if (cset->nranges)
+	    {
+	      if (elem_len <= char_len)
+		{
+		  collseqwc = _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQWC);
+		  in_collseq = __collseq_table_lookup (collseqwc, wc);
+		}
+	      else
+		in_collseq = find_collation_sequence_value (pin, elem_len);
+	    }
+	  /* match with range expression?  */
+	  for (i = 0; i < cset->nranges; ++i)
+	    if (cset->range_starts[i] <= in_collseq
+		&& in_collseq <= cset->range_ends[i])
+	      {
+		match_len = elem_len;
+		goto check_node_accept_bytes_match;
+	      }
+
+	  /* match with equivalence_class?  */
+	  if (cset->nequiv_classes)
+	    {
+	      const unsigned char *cp = pin;
+	      table = (const int32_t *)
+		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_TABLEMB);
+	      weights = (const unsigned char *)
+		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_WEIGHTMB);
+	      extra = (const unsigned char *)
+		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_EXTRAMB);
+	      indirect = (const int32_t *)
+		_NL_CURRENT (LC_COLLATE, _NL_COLLATE_INDIRECTMB);
+	      idx = findidx (&cp);
+	      if (idx > 0)
+		for (i = 0; i < cset->nequiv_classes; ++i)
+		  {
+		    int32_t equiv_class_idx = cset->equiv_classes[i];
+		    size_t weight_len = weights[idx];
+		    if (weight_len == weights[equiv_class_idx])
+		      {
+			int cnt = 0;
+			while (cnt <= weight_len
+			       && (weights[equiv_class_idx + 1 + cnt]
+				   == weights[idx + 1 + cnt]))
+			  ++cnt;
+			if (cnt > weight_len)
+			  {
+			    match_len = elem_len;
+			    goto check_node_accept_bytes_match;
+			  }
+		      }
+		  }
+	    }
+	}
+      else
+# endif /* _LIBC */
+	{
+	  /* match with range expression?  */
+#if __GNUC__ >= 2
+	  wchar_t cmp_buf[] = {L'\0', L'\0', wc, L'\0', L'\0', L'\0'};
+#else
+	  wchar_t cmp_buf[] = {L'\0', L'\0', L'\0', L'\0', L'\0', L'\0'};
+	  cmp_buf[2] = wc;
+#endif
+	  for (i = 0; i < cset->nranges; ++i)
+	    {
+	      cmp_buf[0] = cset->range_starts[i];
+	      cmp_buf[4] = cset->range_ends[i];
+	      if (wcscoll (cmp_buf, cmp_buf + 2) <= 0
+		  && wcscoll (cmp_buf + 2, cmp_buf + 4) <= 0)
+		{
+		  match_len = char_len;
+		  goto check_node_accept_bytes_match;
+		}
+	    }
+	}
+    check_node_accept_bytes_match:
+      if (!cset->non_match)
+	return match_len;
+      else
+	{
+	  if (match_len > 0)
+	    return 0;
+	  else
+	    return (elem_len > char_len) ? elem_len : char_len;
+	}
+    }
+  return 0;
+}
+
+# ifdef _LIBC
+static unsigned int
+internal_function
+find_collation_sequence_value (const unsigned char *mbs, size_t mbs_len)
+{
+  uint32_t nrules = _NL_CURRENT_WORD (LC_COLLATE, _NL_COLLATE_NRULES);
+  if (nrules == 0)
+    {
+      if (mbs_len == 1)
+	{
+	  /* No valid character.  Match it as a single byte character.  */
+	  const unsigned char *collseq = (const unsigned char *)
+	    _NL_CURRENT (LC_COLLATE, _NL_COLLATE_COLLSEQMB);
+	  return collseq[mbs[0]];
+	}
+      return UINT_MAX;
+    }
+  else
+    {
+      int32_t idx;
+      const unsigned char *extra = (const unsigned char *)
+	_NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB);
+      int32_t extrasize = (const unsigned char *)
+	_NL_CURRENT (LC_COLLATE, _NL_COLLATE_SYMB_EXTRAMB + 1) - extra;
+
+      for (idx = 0; idx < extrasize;)
+	{
+	  int mbs_cnt, found = 0;
+	  int32_t elem_mbs_len;
+	  /* Skip the name of collating element name.  */
+	  idx = idx + extra[idx] + 1;
+	  elem_mbs_len = extra[idx++];
+	  if (mbs_len == elem_mbs_len)
+	    {
+	      for (mbs_cnt = 0; mbs_cnt < elem_mbs_len; ++mbs_cnt)
+		if (extra[idx + mbs_cnt] != mbs[mbs_cnt])
+		  break;
+	      if (mbs_cnt == elem_mbs_len)
+		/* Found the entry.  */
+		found = 1;
+	    }
+	  /* Skip the byte sequence of the collating element.  */
+	  idx += elem_mbs_len;
+	  /* Adjust for the alignment.  */
+	  idx = (idx + 3) & ~3;
+	  /* Skip the collation sequence value.  */
+	  idx += sizeof (uint32_t);
+	  /* Skip the wide char sequence of the collating element.  */
+	  idx = idx + sizeof (uint32_t) * (extra[idx] + 1);
+	  /* If we found the entry, return the sequence value.  */
+	  if (found)
+	    return *(uint32_t *) (extra + idx);
+	  /* Skip the collation sequence value.  */
+	  idx += sizeof (uint32_t);
+	}
+      return UINT_MAX;
+    }
+}
+# endif /* _LIBC */
+#endif /* RE_ENABLE_I18N */
+
+/* Check whether the node accepts the byte which is IDX-th
+   byte of the INPUT.  */
+
+static int
+internal_function
+check_node_accept (const re_match_context_t *mctx, const re_token_t *node,
+		   int idx)
+{
+  unsigned char ch;
+  ch = re_string_byte_at (&mctx->input, idx);
+  switch (node->type)
+    {
+    case CHARACTER:
+      if (node->opr.c != ch)
+        return 0;
+      break;
+
+    case SIMPLE_BRACKET:
+      if (!bitset_contain (node->opr.sbcset, ch))
+        return 0;
+      break;
+
+#ifdef RE_ENABLE_I18N
+    case OP_UTF8_PERIOD:
+      if (ch >= 0x80)
+        return 0;
+      /* FALLTHROUGH */
+#endif
+    case OP_PERIOD:
+      if ((ch == '\n' && !(mctx->dfa->syntax & RE_DOT_NEWLINE))
+	  || (ch == '\0' && (mctx->dfa->syntax & RE_DOT_NOT_NULL)))
+	return 0;
+      break;
+
+    default:
+      return 0;
+    }
+
+  if (node->constraint)
+    {
+      /* The node has constraints.  Check whether the current context
+	 satisfies the constraints.  */
+      unsigned int context = re_string_context_at (&mctx->input, idx,
+						   mctx->eflags);
+      if (NOT_SATISFY_NEXT_CONSTRAINT (node->constraint, context))
+	return 0;
+    }
+
+  return 1;
+}
+
+/* Extend the buffers, if the buffers have run out.  */
+
+static reg_errcode_t
+internal_function
+extend_buffers (re_match_context_t *mctx)
+{
+  reg_errcode_t ret;
+  re_string_t *pstr = &mctx->input;
+
+  /* Double the lengthes of the buffers.  */
+  ret = re_string_realloc_buffers (pstr, pstr->bufs_len * 2);
+  if (BE (ret != REG_NOERROR, 0))
+    return ret;
+
+  if (mctx->state_log != NULL)
+    {
+      /* And double the length of state_log.  */
+      /* XXX We have no indication of the size of this buffer.  If this
+	 allocation fail we have no indication that the state_log array
+	 does not have the right size.  */
+      re_dfastate_t **new_array = re_realloc (mctx->state_log, re_dfastate_t *,
+					      pstr->bufs_len + 1);
+      if (BE (new_array == NULL, 0))
+	return REG_ESPACE;
+      mctx->state_log = new_array;
+    }
+
+  /* Then reconstruct the buffers.  */
+  if (pstr->icase)
+    {
+#ifdef RE_ENABLE_I18N
+      if (pstr->mb_cur_max > 1)
+	{
+	  ret = build_wcs_upper_buffer (pstr);
+	  if (BE (ret != REG_NOERROR, 0))
+	    return ret;
+	}
+      else
+#endif /* RE_ENABLE_I18N  */
+	build_upper_buffer (pstr);
+    }
+  else
+    {
+#ifdef RE_ENABLE_I18N
+      if (pstr->mb_cur_max > 1)
+	build_wcs_buffer (pstr);
+      else
+#endif /* RE_ENABLE_I18N  */
+	{
+	  if (pstr->trans != NULL)
+	    re_string_translate_buffer (pstr);
+	}
+    }
+  return REG_NOERROR;
+}
+
+
+/* Functions for matching context.  */
+
+/* Initialize MCTX.  */
+
+static reg_errcode_t
+internal_function
+match_ctx_init (re_match_context_t *mctx, int eflags, int n)
+{
+  mctx->eflags = eflags;
+  mctx->match_last = -1;
+  if (n > 0)
+    {
+      mctx->bkref_ents = re_malloc (struct re_backref_cache_entry, n);
+      mctx->sub_tops = re_malloc (re_sub_match_top_t *, n);
+      if (BE (mctx->bkref_ents == NULL || mctx->sub_tops == NULL, 0))
+	return REG_ESPACE;
+    }
+  /* Already zero-ed by the caller.
+     else
+       mctx->bkref_ents = NULL;
+     mctx->nbkref_ents = 0;
+     mctx->nsub_tops = 0;  */
+  mctx->abkref_ents = n;
+  mctx->max_mb_elem_len = 1;
+  mctx->asub_tops = n;
+  return REG_NOERROR;
+}
+
+/* Clean the entries which depend on the current input in MCTX.
+   This function must be invoked when the matcher changes the start index
+   of the input, or changes the input string.  */
+
+static void
+internal_function
+match_ctx_clean (re_match_context_t *mctx)
+{
+  int st_idx;
+  for (st_idx = 0; st_idx < mctx->nsub_tops; ++st_idx)
+    {
+      int sl_idx;
+      re_sub_match_top_t *top = mctx->sub_tops[st_idx];
+      for (sl_idx = 0; sl_idx < top->nlasts; ++sl_idx)
+	{
+	  re_sub_match_last_t *last = top->lasts[sl_idx];
+	  re_free (last->path.array);
+	  re_free (last);
+	}
+      re_free (top->lasts);
+      if (top->path)
+	{
+	  re_free (top->path->array);
+	  re_free (top->path);
+	}
+      free (top);
+    }
+
+  mctx->nsub_tops = 0;
+  mctx->nbkref_ents = 0;
+}
+
+/* Free all the memory associated with MCTX.  */
+
+static void
+internal_function
+match_ctx_free (re_match_context_t *mctx)
+{
+  /* First, free all the memory associated with MCTX->SUB_TOPS.  */
+  match_ctx_clean (mctx);
+  re_free (mctx->sub_tops);
+  re_free (mctx->bkref_ents);
+}
+
+/* Add a new backreference entry to MCTX.
+   Note that we assume that caller never call this function with duplicate
+   entry, and call with STR_IDX which isn't smaller than any existing entry.
+*/
+
+static reg_errcode_t
+internal_function
+match_ctx_add_entry (re_match_context_t *mctx, int node, int str_idx, int from,
+		     int to)
+{
+  if (mctx->nbkref_ents >= mctx->abkref_ents)
+    {
+      struct re_backref_cache_entry* new_entry;
+      new_entry = re_realloc (mctx->bkref_ents, struct re_backref_cache_entry,
+			      mctx->abkref_ents * 2);
+      if (BE (new_entry == NULL, 0))
+	{
+	  re_free (mctx->bkref_ents);
+	  return REG_ESPACE;
+	}
+      mctx->bkref_ents = new_entry;
+      memset (mctx->bkref_ents + mctx->nbkref_ents, '\0',
+	      sizeof (struct re_backref_cache_entry) * mctx->abkref_ents);
+      mctx->abkref_ents *= 2;
+    }
+  if (mctx->nbkref_ents > 0
+      && mctx->bkref_ents[mctx->nbkref_ents - 1].str_idx == str_idx)
+    mctx->bkref_ents[mctx->nbkref_ents - 1].more = 1;
+
+  mctx->bkref_ents[mctx->nbkref_ents].node = node;
+  mctx->bkref_ents[mctx->nbkref_ents].str_idx = str_idx;
+  mctx->bkref_ents[mctx->nbkref_ents].subexp_from = from;
+  mctx->bkref_ents[mctx->nbkref_ents].subexp_to = to;
+
+  /* This is a cache that saves negative results of check_dst_limits_calc_pos.
+     If bit N is clear, means that this entry won't epsilon-transition to
+     an OP_OPEN_SUBEXP or OP_CLOSE_SUBEXP for the N+1-th subexpression.  If
+     it is set, check_dst_limits_calc_pos_1 will recurse and try to find one
+     such node.
+
+     A backreference does not epsilon-transition unless it is empty, so set
+     to all zeros if FROM != TO.  */
+  mctx->bkref_ents[mctx->nbkref_ents].eps_reachable_subexps_map
+    = (from == to ? ~0 : 0);
+
+  mctx->bkref_ents[mctx->nbkref_ents++].more = 0;
+  if (mctx->max_mb_elem_len < to - from)
+    mctx->max_mb_elem_len = to - from;
+  return REG_NOERROR;
+}
+
+/* Search for the first entry which has the same str_idx, or -1 if none is
+   found.  Note that MCTX->BKREF_ENTS is already sorted by MCTX->STR_IDX.  */
+
+static int
+internal_function
+search_cur_bkref_entry (const re_match_context_t *mctx, int str_idx)
+{
+  int left, right, mid, last;
+  last = right = mctx->nbkref_ents;
+  for (left = 0; left < right;)
+    {
+      mid = (left + right) / 2;
+      if (mctx->bkref_ents[mid].str_idx < str_idx)
+	left = mid + 1;
+      else
+	right = mid;
+    }
+  if (left < last && mctx->bkref_ents[left].str_idx == str_idx)
+    return left;
+  else
+    return -1;
+}
+
+/* Register the node NODE, whose type is OP_OPEN_SUBEXP, and which matches
+   at STR_IDX.  */
+
+static reg_errcode_t
+internal_function
+match_ctx_add_subtop (re_match_context_t *mctx, int node, int str_idx)
+{
+#ifdef DEBUG
+  assert (mctx->sub_tops != NULL);
+  assert (mctx->asub_tops > 0);
+#endif
+  if (BE (mctx->nsub_tops == mctx->asub_tops, 0))
+    {
+      int new_asub_tops = mctx->asub_tops * 2;
+      re_sub_match_top_t **new_array = re_realloc (mctx->sub_tops,
+						   re_sub_match_top_t *,
+						   new_asub_tops);
+      if (BE (new_array == NULL, 0))
+	return REG_ESPACE;
+      mctx->sub_tops = new_array;
+      mctx->asub_tops = new_asub_tops;
+    }
+  mctx->sub_tops[mctx->nsub_tops] = calloc (1, sizeof (re_sub_match_top_t));
+  if (BE (mctx->sub_tops[mctx->nsub_tops] == NULL, 0))
+    return REG_ESPACE;
+  mctx->sub_tops[mctx->nsub_tops]->node = node;
+  mctx->sub_tops[mctx->nsub_tops++]->str_idx = str_idx;
+  return REG_NOERROR;
+}
+
+/* Register the node NODE, whose type is OP_CLOSE_SUBEXP, and which matches
+   at STR_IDX, whose corresponding OP_OPEN_SUBEXP is SUB_TOP.  */
+
+static re_sub_match_last_t *
+internal_function
+match_ctx_add_sublast (re_sub_match_top_t *subtop, int node, int str_idx)
+{
+  re_sub_match_last_t *new_entry;
+  if (BE (subtop->nlasts == subtop->alasts, 0))
+    {
+      int new_alasts = 2 * subtop->alasts + 1;
+      re_sub_match_last_t **new_array = re_realloc (subtop->lasts,
+						    re_sub_match_last_t *,
+						    new_alasts);
+      if (BE (new_array == NULL, 0))
+	return NULL;
+      subtop->lasts = new_array;
+      subtop->alasts = new_alasts;
+    }
+  new_entry = calloc (1, sizeof (re_sub_match_last_t));
+  if (BE (new_entry != NULL, 1))
+    {
+      subtop->lasts[subtop->nlasts] = new_entry;
+      new_entry->node = node;
+      new_entry->str_idx = str_idx;
+      ++subtop->nlasts;
+    }
+  return new_entry;
+}
+
+static void
+internal_function
+sift_ctx_init (re_sift_context_t *sctx, re_dfastate_t **sifted_sts,
+	       re_dfastate_t **limited_sts, int last_node, int last_str_idx)
+{
+  sctx->sifted_states = sifted_sts;
+  sctx->limited_states = limited_sts;
+  sctx->last_node = last_node;
+  sctx->last_str_idx = last_str_idx;
+  re_node_set_init_empty (&sctx->limits);
+}
diff --git a/Build/source/texk/chktex/version.ac b/Build/source/texk/chktex/version.ac
index 0cfc38830b8..a852157fb4b 100644
--- a/Build/source/texk/chktex/version.ac
+++ b/Build/source/texk/chktex/version.ac
@@ -8,4 +8,4 @@ dnl
 dnl --------------------------------------------------------
 dnl
 dnl  m4-include this file to define the current chktex version
-m4_define([chktex_version], [1.6.6])
+m4_define([chktex_version], [1.7.1])