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-rw-r--r--lib/gl/m4/wchar.m4103
1 files changed, 75 insertions, 28 deletions
diff --git a/lib/gl/m4/wchar.m4 b/lib/gl/m4/wchar.m4
index ce53a45cf5..e81485d01e 100644
--- a/lib/gl/m4/wchar.m4
+++ b/lib/gl/m4/wchar.m4
@@ -1,23 +1,30 @@
dnl A placeholder for ISO C99 <wchar.h>, for platforms that have issues.
-dnl Copyright (C) 2007-2009 Free Software Foundation, Inc.
+dnl Copyright (C) 2007-2010 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.
dnl Written by Eric Blake.
-# wchar.m4 serial 25
+# wchar.m4 serial 31
AC_DEFUN([gl_WCHAR_H],
[
AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
- AC_CACHE_CHECK([whether <wchar.h> is standalone],
- [gl_cv_header_wchar_h_standalone],
- [AC_COMPILE_IFELSE([[#include <wchar.h>
-wchar_t w;]],
- [gl_cv_header_wchar_h_standalone=yes],
- [gl_cv_header_wchar_h_standalone=no])])
+ AC_REQUIRE([gl_WCHAR_H_INLINE_OK])
+ dnl Prepare for creating substitute <wchar.h>.
+ dnl Check for <wchar.h> (missing in Linux uClibc when built without wide
+ dnl character support).
+ dnl <wchar.h> is always overridden, because of GNULIB_POSIXCHECK.
+ AC_CHECK_HEADERS_ONCE([wchar.h])
+ gl_CHECK_NEXT_HEADERS([wchar.h])
+ if test $ac_cv_header_wchar_h = yes; then
+ HAVE_WCHAR_H=1
+ else
+ HAVE_WCHAR_H=0
+ fi
+ AC_SUBST([HAVE_WCHAR_H])
AC_REQUIRE([gt_TYPE_WINT_T])
if test $gt_cv_c_wint_t = yes; then
@@ -27,32 +34,73 @@ wchar_t w;]],
fi
AC_SUBST([HAVE_WINT_T])
- dnl If <stddef.h> is replaced, then <wchar.h> must also be replaced.
- AC_REQUIRE([gl_STDDEF_H])
-
- if test $gl_cv_header_wchar_h_standalone != yes || test $gt_cv_c_wint_t != yes || test -n "$STDDEF_H"; then
- WCHAR_H=wchar.h
- fi
+ dnl Check for declarations of anything we want to poison if the
+ dnl corresponding gnulib module is not in use.
+ gl_WARN_ON_USE_PREPARE([[
+/* Some systems require additional headers. */
+#ifndef __GLIBC__
+# include <stddef.h>
+# include <stdio.h>
+# include <time.h>
+#endif
+#include <wchar.h>
+ ]], [btowc wctob mbsinit mbrtowc mbrlen mbsrtowcs mbsnrtowcs wcrtomb
+ wcsrtombs wcsnrtombs wcwidth])
+])
- dnl Prepare for creating substitute <wchar.h>.
- dnl Do it always: WCHAR_H may be empty here but can be set later.
- dnl Check for <wchar.h> (missing in Linux uClibc when built without wide
- dnl character support).
- AC_CHECK_HEADERS_ONCE([wchar.h])
- if test $ac_cv_header_wchar_h = yes; then
- HAVE_WCHAR_H=1
- else
- HAVE_WCHAR_H=0
+dnl Check whether <wchar.h> is usable at all.
+AC_DEFUN([gl_WCHAR_H_INLINE_OK],
+[
+ dnl Test whether <wchar.h> suffers due to the transition from '__inline' to
+ dnl 'gnu_inline'. See <http://sourceware.org/bugzilla/show_bug.cgi?id=4022>
+ dnl and <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42440>. In summary,
+ dnl glibc version 2.5 or older, together with gcc version 4.3 or newer and
+ dnl the option -std=c99 or -std=gnu99, leads to a broken <wchar.h>.
+ AC_CACHE_CHECK([whether <wchar.h> uses 'inline' correctly],
+ [gl_cv_header_wchar_h_correct_inline],
+ [gl_cv_header_wchar_h_correct_inline=yes
+ AC_LANG_CONFTEST([
+ AC_LANG_SOURCE([[#define wcstod renamed_wcstod
+#include <wchar.h>
+extern int zero (void);
+int main () { return zero(); }
+]])])
+ if AC_TRY_EVAL([ac_compile]); then
+ mv conftest.$ac_objext conftest1.$ac_objext
+ AC_LANG_CONFTEST([
+ AC_LANG_SOURCE([[#define wcstod renamed_wcstod
+#include <wchar.h>
+int zero (void) { return 0; }
+]])])
+ if AC_TRY_EVAL([ac_compile]); then
+ mv conftest.$ac_objext conftest2.$ac_objext
+ if $CC -o conftest$ac_exeext $CFLAGS $LDFLAGS conftest1.$ac_objext conftest2.$ac_objext $LIBS >&AS_MESSAGE_LOG_FD 2>&1; then
+ :
+ else
+ gl_cv_header_wchar_h_correct_inline=no
+ fi
+ fi
+ fi
+ rm -f conftest1.$ac_objext conftest2.$ac_objext conftest$ac_exeext
+ ])
+ if test $gl_cv_header_wchar_h_correct_inline = no; then
+ AC_MSG_ERROR([<wchar.h> cannot be used with this compiler ($CC $CFLAGS $CPPFLAGS).
+This is a known interoperability problem of glibc <= 2.5 with gcc >= 4.3 in
+C99 mode. You have four options:
+ - Add the flag -fgnu89-inline to CC and reconfigure, or
+ - Fix your include files, using parts of
+ <http://sourceware.org/git/?p=glibc.git;a=commitdiff;h=b037a293a48718af30d706c2e18c929d0e69a621>, or
+ - Use a gcc version older than 4.3, or
+ - Don't use the flags -std=c99 or -std=gnu99.
+Configuration aborted.])
fi
- AC_SUBST([HAVE_WCHAR_H])
- gl_CHECK_NEXT_HEADERS([wchar.h])
])
dnl Unconditionally enables the replacement of <wchar.h>.
AC_DEFUN([gl_REPLACE_WCHAR_H],
[
- AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
- WCHAR_H=wchar.h
+ dnl This is a no-op, because <wchar.h> is always overridden.
+ :
])
AC_DEFUN([gl_WCHAR_MODULE_INDICATOR],
@@ -99,5 +147,4 @@ AC_DEFUN([gl_WCHAR_H_DEFAULTS],
REPLACE_WCSRTOMBS=0; AC_SUBST([REPLACE_WCSRTOMBS])
REPLACE_WCSNRTOMBS=0; AC_SUBST([REPLACE_WCSNRTOMBS])
REPLACE_WCWIDTH=0; AC_SUBST([REPLACE_WCWIDTH])
- WCHAR_H=''; AC_SUBST([WCHAR_H])
])