-# perror.m4 serial 1
-dnl Copyright (C) 2008 Free Software Foundation, Inc.
+# perror.m4 serial 6
+dnl Copyright (C) 2008-2012 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.
[
AC_REQUIRE([gl_STDIO_H_DEFAULTS])
AC_REQUIRE([gl_HEADER_ERRNO_H])
- if test -n "$ERRNO_H"; then
+ AC_REQUIRE([gl_FUNC_STRERROR_R])
+ AC_REQUIRE([gl_FUNC_STRERROR_0])
+ dnl We intentionally do not check for the broader REPLACE_STRERROR_R,
+ dnl since on glibc systems, strerror_r is replaced only for signature
+ dnl issues, and perror is just fine. Rather, we only want to
+ dnl replace perror if strerror_r was replaced for a content fix.
+ if test "$ERRNO_H:$REPLACE_STRERROR_0" != :0; then
dnl The system's perror() cannot know about the new errno values we add
- dnl to <errno.h>. Replace it.
+ dnl to <errno.h>, or any fix for strerror(0). Replace it.
REPLACE_PERROR=1
- AC_LIBOBJ([perror])
fi
+ case ${gl_cv_func_strerror_r_works-unset} in
+ unset|*yes)
+ AC_CACHE_CHECK([whether perror matches strerror],
+ [gl_cv_func_perror_works],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <errno.h>
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <string.h>
+ ]],
+ [[char *str = strerror (-1);
+ if (!getenv("CONFTEST_OUTPUT")) return 0;
+ if (!str) str = "";
+ puts (str);
+ errno = -1;
+ perror ("");
+ return 0;
+ ]])],
+ [if CONFTEST_OUTPUT=1 ./conftest$EXEEXT >conftest.txt1 2>conftest.txt2 \
+ && cmp conftest.txt1 conftest.txt2 >/dev/null; then
+ gl_cv_func_perror_works=yes
+ else
+ gl_cv_func_perror_works=no
+ fi
+ rm -rf conftest.txt1 conftest.txt2],
+ [gl_cv_func_perror_works=no],
+ [dnl Guess no when cross-compiling.
+ gl_cv_func_perror_works="guessing no"
+ ])
+ ])
+ if test "$gl_cv_func_perror_works" != yes; then
+ REPLACE_PERROR=1
+ fi
+ ;;
+ *)
+ dnl The system's perror() probably inherits the bugs in the
+ dnl system's strerror_r(). Replace it.
+ REPLACE_PERROR=1
+ ;;
+ esac
])