diff options
Diffstat (limited to 'Build/source/extra/xz/m4/visibility.m4')
-rw-r--r-- | Build/source/extra/xz/m4/visibility.m4 | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/Build/source/extra/xz/m4/visibility.m4 b/Build/source/extra/xz/m4/visibility.m4 index 2ff6330aa42..077c4765ec2 100644 --- a/Build/source/extra/xz/m4/visibility.m4 +++ b/Build/source/extra/xz/m4/visibility.m4 @@ -1,5 +1,5 @@ -# visibility.m4 serial 1 (gettext-0.15) -dnl Copyright (C) 2005 Free Software Foundation, Inc. +# visibility.m4 serial 3 (gettext-0.18) +dnl Copyright (C) 2005, 2008-2010 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. @@ -26,18 +26,40 @@ AC_DEFUN([gl_VISIBILITY], CFLAG_VISIBILITY= HAVE_VISIBILITY=0 if test -n "$GCC"; then + dnl First, check whether -Werror can be added to the command line, or + dnl whether it leads to an error because of some other option that the + dnl user has put into $CC $CFLAGS $CPPFLAGS. + AC_MSG_CHECKING([whether the -Werror option is usable]) + AC_CACHE_VAL([gl_cv_cc_vis_werror], [ + gl_save_CFLAGS="$CFLAGS" + CFLAGS="$CFLAGS -Werror" + AC_TRY_COMPILE([], [], + [gl_cv_cc_vis_werror=yes], + [gl_cv_cc_vis_werror=no]) + CFLAGS="$gl_save_CFLAGS"]) + AC_MSG_RESULT([$gl_cv_cc_vis_werror]) + dnl Now check whether visibility declarations are supported. AC_MSG_CHECKING([for simple visibility declarations]) - AC_CACHE_VAL(gl_cv_cc_visibility, [ + AC_CACHE_VAL([gl_cv_cc_visibility], [ gl_save_CFLAGS="$CFLAGS" CFLAGS="$CFLAGS -fvisibility=hidden" + dnl We use the option -Werror and a function dummyfunc, because on some + dnl platforms (Cygwin 1.7) the use of -fvisibility triggers a warning + dnl "visibility attribute not supported in this configuration; ignored" + dnl at the first function definition in every compilation unit, and we + dnl don't want to use the option in this case. + if test $gl_cv_cc_vis_werror = yes; then + CFLAGS="$CFLAGS -Werror" + fi AC_TRY_COMPILE( [extern __attribute__((__visibility__("hidden"))) int hiddenvar; extern __attribute__((__visibility__("default"))) int exportedvar; extern __attribute__((__visibility__("hidden"))) int hiddenfunc (void); - extern __attribute__((__visibility__("default"))) int exportedfunc (void);], + extern __attribute__((__visibility__("default"))) int exportedfunc (void); + void dummyfunc (void) {}], [], - gl_cv_cc_visibility=yes, - gl_cv_cc_visibility=no) + [gl_cv_cc_visibility=yes], + [gl_cv_cc_visibility=no]) CFLAGS="$gl_save_CFLAGS"]) AC_MSG_RESULT([$gl_cv_cc_visibility]) if test $gl_cv_cc_visibility = yes; then |