X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fstrerror_r.m4;h=72c75515c2dbec85f65d5a3b5b7462b74207ea5b;hb=77531436705e50d9efe2bb7d948fd4ebe43e69ad;hp=34a2d246cf53add21954fd92c55a36e08c1aeb20;hpb=5c28b65b2f8bcb6fca6193caa51c075a6c687247;p=gnulib.git

diff --git a/m4/strerror_r.m4 b/m4/strerror_r.m4
index 34a2d246c..72c75515c 100644
--- a/m4/strerror_r.m4
+++ b/m4/strerror_r.m4
@@ -1,5 +1,7 @@
-#serial 1000
+#serial 1001
 # Experimental replacement for the function in the latest CVS autoconf.
+# If the compile-test says strerror_r doesn't work, then resort to a
+# `run'-test that works on BeOS and segfaults on DEC Unix.
 # Use with the error.c file in ../lib.
 
 undefine([AC_FUNC_STRERROR_R])
@@ -21,20 +23,42 @@ if test $ac_cv_func_strerror_r = yes; then
 #       if HAVE_STRING_H
 #        include <string.h>
 #       endif
-#ifndef HAVE_DECL_STRERROR_R
-"this configure-time declaration test was not run"
-#endif
-#if !HAVE_DECL_STRERROR_R
-char *strerror_r ();
-#endif
      ],
      [
-       char buf;
-       char x = *strerror_r (0, &buf, sizeof buf);
+       char buf[100];
+       char x = *strerror_r (0, buf, sizeof buf);
      ],
      ac_cv_func_strerror_r_works=yes,
      ac_cv_func_strerror_r_works=no
     )
+    if test $ac_cv_func_strerror_r_works = no; then
+      # strerror_r seems not to work, but now we have to choose between
+      # systems that have relatively inaccessible declarations for the
+      # function.  BeOS and DEC UNIX 4.0 fall in this category, but the
+      # former has a strerror_r that returns char*, while the latter
+      # has a strerror_r that returns `int'.
+      # This test should segfault on the DEC system.
+      AC_TRY_RUN(
+       [
+#       include <stdio.h>
+#       include <string.h>
+#       include <ctype.h>
+
+	extern char *strerror_r ();
+
+	int
+	main ()
+	{
+	  char buf[100];
+	  char x = *strerror_r (0, buf, sizeof buf);
+	  exit (!isalpha (x));
+	}
+       ],
+       ac_cv_func_strerror_r_works=yes,
+       ac_cv_func_strerror_r_works=no,
+       ac_cv_func_strerror_r_works=no)
+    fi
+
     if test $ac_cv_func_strerror_r_works = yes; then
       AC_DEFINE_UNQUOTED(HAVE_WORKING_STRERROR_R, 1,
         [Define to 1 if `strerror_r' returns a string.])