Fix strerror on Interix.

[gnulib.git] / m4 / strerror.m4

diff --git a/m4/strerror.m4 b/m4/strerror.m4
index bbcda30..52f3e3f 100644 (file)
--- a/m4/strerror.m4
+++ b/m4/strerror.m4
@@ -1,4 +1,4 @@
-# strerror.m4 serial 3
+# strerror.m4 serial 4
 dnl Copyright (C) 2002, 2007 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -6,10 +6,11 @@ dnl with or without modifications, as long as this notice is preserved.
 
 AC_DEFUN([gl_FUNC_STRERROR],
 [
-  AC_CHECK_FUNCS_ONCE([strerror])
-  if test $ac_cv_func_strerror = no; then
+  AC_REQUIRE([gl_FUNC_STRERROR_SEPARATE])
+  if test $gl_cv_func_working_strerror = no; then
     AC_LIBOBJ([strerror])
-    gl_PREREQ_STRERROR
+    AC_DEFINE_UNQUOTED([REPLACE_STRERROR], [$REPLACE_STRERROR],
+      [Define this to 1 if strerror is broken.])
   fi
 ])
 
@@ -18,6 +19,28 @@ AC_DEFUN([gl_FUNC_STRERROR_SEPARATE],
 [
   AC_CHECK_FUNCS_ONCE([strerror])
   gl_PREREQ_STRERROR
+  if test $ac_cv_func_strerror = no; then
+    HAVE_DECL_STRERROR=0
+    gl_cv_func_working_strerror=no
+  else
+    AC_CACHE_CHECK([for working strerror function],
+     [gl_cv_func_working_strerror],
+     [AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM([
+#include <string.h>
+        ], [return !*strerror (-2);])],
+       [gl_cv_func_working_strerror=yes], [gl_cv_func_working_strerror=no],
+       [dnl assume success except on Interix
+       AC_EGREP_CPP([assuming success], [
+#ifndef __INTERIX
+  assuming success
+#endif
+       ], [gl_cv_func_working_strerror=yes],
+       [gl_cv_func_working_strerror=no])])])
+    if test $gl_cv_func_working_strerror = no ; then
+      REPLACE_STRERROR=1
+    fi
+  fi
 ])
 
 # Prerequisites of lib/strerror.c.