diff options
Diffstat (limited to 'gl/m4/threadlib.m4')
| -rw-r--r-- | gl/m4/threadlib.m4 | 54 |
1 files changed, 44 insertions, 10 deletions
diff --git a/gl/m4/threadlib.m4 b/gl/m4/threadlib.m4 index 3dd38aa8..05cc4ffa 100644 --- a/gl/m4/threadlib.m4 +++ b/gl/m4/threadlib.m4 @@ -1,5 +1,5 @@ -# threadlib.m4 serial 3 (gettext-0.18) -dnl Copyright (C) 2005-2009 Free Software Foundation, Inc. +# threadlib.m4 serial 5 (gettext-0.18) +dnl Copyright (C) 2005-2010 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. @@ -52,13 +52,24 @@ AC_HELP_STRING([--disable-threads], [build without multithread safety]), [if test -n "$gl_use_threads_default"; then gl_use_threads="$gl_use_threads_default" else +changequote(,)dnl case "$host_os" in dnl Disable multithreading by default on OSF/1, because it interferes dnl with fork()/exec(): When msgexec is linked with -lpthread, its dnl child process gets an endless segmentation fault inside execvp(). + dnl Disable multithreading by default on Cygwin 1.5.x, because it has + dnl bugs that lead to endless loops or crashes. See + dnl <http://cygwin.com/ml/cygwin/2009-08/msg00283.html>. osf*) gl_use_threads=no ;; + cygwin*) + case `uname -r` in + 1.[0-5].*) gl_use_threads=no ;; + *) gl_use_threads=yes ;; + esac + ;; *) gl_use_threads=yes ;; esac +changequote([,])dnl fi ]) if test "$gl_use_threads" = yes || test "$gl_use_threads" = posix; then @@ -96,11 +107,34 @@ AC_DEFUN([gl_THREADLIB_BODY], LTLIBMULTITHREAD= if test "$gl_use_threads" != no; then dnl Check whether the compiler and linker support weak declarations. - AC_MSG_CHECKING([whether imported symbols can be declared weak]) - gl_have_weak=no - AC_TRY_LINK([extern void xyzzy (); -#pragma weak xyzzy], [xyzzy();], [gl_have_weak=yes]) - AC_MSG_RESULT([$gl_have_weak]) + AC_CACHE_CHECK([whether imported symbols can be declared weak], + [gl_cv_have_weak], + [gl_cv_have_weak=no + dnl First, test whether the compiler accepts it syntactically. + AC_TRY_LINK([extern void xyzzy (); +#pragma weak xyzzy], [xyzzy();], [gl_cv_have_weak=maybe]) + if test $gl_cv_have_weak = maybe; then + dnl Second, test whether it actually works. On Cygwin 1.7.2, with + dnl gcc 4.3, symbols declared weak always evaluate to the address 0. + AC_TRY_RUN([ +#include <stdio.h> +#pragma weak fputs +int main () +{ + return (fputs == NULL); +}], [gl_cv_have_weak=yes], [gl_cv_have_weak=no], + [dnl When cross-compiling, assume that only ELF platforms support + dnl weak symbols. + AC_EGREP_CPP([Extensible Linking Format], + [#ifdef __ELF__ + Extensible Linking Format + #endif + ], + [gl_cv_have_weak="guessing yes"], + [gl_cv_have_weak="guessing no"]) + ]) + fi + ]) if test "$gl_use_threads" = yes || test "$gl_use_threads" = posix; then # On OSF/1, the compiler needs the flag -pthread or -D_REENTRANT so that # it groks <pthread.h>. It's added above, in gl_THREADLIB_EARLY_BODY. @@ -154,7 +188,7 @@ AC_DEFUN([gl_THREADLIB_BODY], AC_DEFINE([USE_POSIX_THREADS], [1], [Define if the POSIX multithreading library can be used.]) if test -n "$LIBMULTITHREAD" || test -n "$LTLIBMULTITHREAD"; then - if test $gl_have_weak = yes; then + if case "$gl_cv_have_weak" in *yes) true;; *) false;; esac; then AC_DEFINE([USE_POSIX_THREADS_WEAK], [1], [Define if references to the POSIX multithreading library should be made weak.]) LIBTHREAD= @@ -182,7 +216,7 @@ AC_DEFUN([gl_THREADLIB_BODY], LTLIBMULTITHREAD="$LTLIBTHREAD" AC_DEFINE([USE_SOLARIS_THREADS], [1], [Define if the old Solaris multithreading library can be used.]) - if test $gl_have_weak = yes; then + if case "$gl_cv_have_weak" in *yes) true;; *) false;; esac; then AC_DEFINE([USE_SOLARIS_THREADS_WEAK], [1], [Define if references to the old Solaris multithreading library should be made weak.]) LIBTHREAD= @@ -208,7 +242,7 @@ AC_DEFUN([gl_THREADLIB_BODY], AC_DEFINE([USE_PTH_THREADS], [1], [Define if the GNU Pth multithreading library can be used.]) if test -n "$LIBMULTITHREAD" || test -n "$LTLIBMULTITHREAD"; then - if test $gl_have_weak = yes; then + if case "$gl_cv_have_weak" in *yes) true;; *) false;; esac; then AC_DEFINE([USE_PTH_THREADS_WEAK], [1], [Define if references to the GNU Pth multithreading library should be made weak.]) LIBTHREAD= |