-# memcmp.m4 serial 14
-dnl Copyright (C) 2002-2004, 2007-2009 Free Software Foundation, Inc.
+# memcmp.m4 serial 16
+dnl Copyright (C) 2002-2004, 2007-2012 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_DEFUN([gl_FUNC_MEMCMP],
[
- if test $cross_compiling != no; then
- # AC_FUNC_MEMCMP as of 2.62 defaults to 'no' when cross compiling.
- # We default to yes if memcmp appears to exist, which works
- # better for MinGW.
- AC_CACHE_CHECK([whether cross-compiling target has memcmp],
- [ac_cv_func_memcmp_working],
- [AC_LINK_IFELSE([
- AC_LANG_PROGRAM([[#include <string.h>
- ]], [[int ret = memcmp ("foo", "bar", 0);]])],
- [ac_cv_func_memcmp_working=yes],
- [ac_cv_func_memcmp_working=no])])
- fi
- AC_FUNC_MEMCMP
- dnl Note: AC_FUNC_MEMCMP does AC_LIBOBJ([memcmp]).
- if test $ac_cv_func_memcmp_working = no; then
+ dnl We don't use AC_FUNC_MEMCMP any more, because it is no longer maintained
+ dnl in Autoconf and because it invokes AC_LIBOBJ.
+ AC_CACHE_CHECK([for working memcmp], [gl_cv_func_memcmp_working],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [AC_INCLUDES_DEFAULT],
+ [[/* Some versions of memcmp are not 8-bit clean. */
+ char c0 = '\100', c1 = '\200', c2 = '\201';
+ if (memcmp(&c0, &c2, 1) >= 0 || memcmp(&c1, &c2, 1) >= 0)
+ return 1;
+ /* The Next x86 OpenStep bug shows up only when comparing 16 bytes
+ or more and with at least one buffer not starting on a 4-byte
+ boundary. William Lewis provided this test program. */
+ {
+ char foo[21];
+ char bar[21];
+ int i;
+ for (i = 0; i < 4; i++)
+ {
+ char *a = foo + i;
+ char *b = bar + i;
+ strcpy (a, "--------01111111");
+ strcpy (b, "--------10000000");
+ if (memcmp (a, b, 16) >= 0)
+ return 1;
+ }
+ return 0;
+ }
+ ]])],
+ [gl_cv_func_memcmp_working=yes],
+ [gl_cv_func_memcmp_working=no],
+ [dnl When cross-compiling, guess memcmp works when it exists.
+ dnl This is useful for mingw.
+ AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <string.h>]],
+ [[int ret = memcmp ("foo", "bar", 0);]])],
+ [gl_cv_func_memcmp_working="guessing yes"],
+ [gl_cv_func_memcmp_working="guessing no"])
+ ])
+ ])
+ case "$gl_cv_func_memcmp_working" in
+ *yes) gl_func_memcmp=yes ;;
+ *) gl_func_memcmp=no ;;
+ esac
+ if test $gl_func_memcmp = no; then
AC_DEFINE([memcmp], [rpl_memcmp],
[Define to rpl_memcmp if the replacement function should be used.])
- gl_PREREQ_MEMCMP
fi
])