1 files changed, 44 insertions, 3 deletions
diff --git a/Build/source/libs/libpng/configure b/Build/source/libs/libpng/configure
index 71fd992b119..558ad9a4bf5 100755
--- a/Build/source/libs/libpng/configure
+++ b/Build/source/libs/libpng/configure
@@ -5610,6 +5610,9 @@ else
 fi
 
 
+kpse_save_CPPFLAGS=$CPPFLAGS
+kpse_save_LIBS=$LIBS
+
 ## _KPSE_INIT: Initialize TL infrastructure
 kpse_BLD=`(cd "./../../." && pwd)`
 kpse_SRC=`(cd "$srcdir/../../." && pwd)`
@@ -5648,6 +5651,47 @@ $(ZLIB_DEPEND): ${top_builddir}/../../libs/zlib/include/zconf.h
 ${top_builddir}/../../libs/zlib/include/zconf.h:
 	cd ${top_builddir}/../../libs/zlib && $(MAKE) $(AM_MAKEFLAGS) rebuild'
 fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if <zlib.h> defines 'z_const'" >&5
+$as_echo_n "checking if <zlib.h> defines 'z_const'... " >&6; }
+if ${kpse_cv_have_decl_z_const+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  eval CPPFLAGS=\"$ZLIB_INCLUDES \$CPPFLAGS\"
+eval LIBS=\"$ZLIB_LIBS \$LIBS\"
+
+                cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <zlib.h>
+int
+main ()
+{
+z_const char * foo();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  kpse_cv_have_decl_z_const=yes
+else
+  kpse_cv_have_decl_z_const=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+                CPPFLAGS=$kpse_save_CPPFLAGS
+LIBS=$kpse_save_LIBS
+
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $kpse_cv_have_decl_z_const" >&5
+$as_echo "$kpse_cv_have_decl_z_const" >&6; }
+case $kpse_cv_have_decl_z_const in #(
+  yes) :
+
+$as_echo "#define ZLIB_CONST 1" >>confdefs.h
+ ;; #(
+  *) :
+
+$as_echo "#define z_const /**/" >>confdefs.h
+ ;;
+esac
 
 
  if test "x$enable_build" != xno; then
@@ -5661,9 +5705,6 @@ fi
 
 if test "x$enable_build" != xno || test -f config.force; then
 
-kpse_save_CPPFLAGS=$CPPFLAGS
-kpse_save_LIBS=$LIBS
-
 eval CPPFLAGS=\"$ZLIB_INCLUDES \$CPPFLAGS\"
 eval LIBS=\"$ZLIB_LIBS \$LIBS\"