-#serial 4
+# memcmp.m4 serial 14
+dnl Copyright (C) 2002-2004, 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 A replacement for autoconf's AC_FUNC_MEMCMP that detects
-dnl the losing memcmp on some x86 Next systems.
-AC_DEFUN(jm_AC_FUNC_MEMCMP,
-[AC_CACHE_CHECK([for working memcmp], jm_cv_func_memcmp_working,
-[AC_TRY_RUN(
-[int
-main ()
-{
- /* Some versions of memcmp are not 8-bit clean. */
- char c0 = 0x40, c1 = 0x80, c2 = 0x81;
- if (memcmp(&c0, &c2, 1) >= 0 || memcmp(&c1, &c2, 1) >= 0)
- exit (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)
- exit (1);
- }
- exit (0);
- }
-}],
- jm_cv_func_memcmp_working=yes,
- jm_cv_func_memcmp_working=no,
- jm_cv_func_memcmp_working=no)])
-test $jm_cv_func_memcmp_working = no \
- && LIBOBJS="$LIBOBJS memcmp.$ac_objext"
-AC_SUBST(LIBOBJS)dnl
+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
+ AC_DEFINE([memcmp], [rpl_memcmp],
+ [Define to rpl_memcmp if the replacement function should be used.])
+ gl_PREREQ_MEMCMP
+ fi
])
-AC_DEFUN(jm_FUNC_MEMCMP,
-[AC_REQUIRE([jm_AC_FUNC_MEMCMP])dnl
- if test $jm_cv_func_memcmp_working = no; then
- AC_DEFINE_UNQUOTED(memcmp, rpl_memcmp,
- [Define to rpl_memcmp if the replacement function should be used.])
- fi
-])
+# Prerequisites of lib/memcmp.c.
+AC_DEFUN([gl_PREREQ_MEMCMP], [:])