[x11-wm/fvwm2]: built with clang 3.1 failed

[Paul Ambrose Ambrose]

when configuring, the configure, line 15373  has problem with the clang 3.1

   switch (*p = p = *c) { case 0: printf("%Q", c, p); }
  *c = &i; c = p;
  while (1 || (unsigned int)3 >= 0 || ((int)-1) == ((unsigned int)1));
  return;                 //line 15373
  ;
  return 0;
}
which cause configure fail, I manually change
    return;
into
    return 1;
and it works, but when add a patch file, patch-configure
cat ../../files/patch-configure

--- configure.orig      2012-06-04 20:35:58.000000000 +0800
+++ configure   2012-06-04 20:36:47.000000000 +0800
@@ -6492,7 +6492,7 @@
   switch (*p = p = *c) { case 0: printf("%Q", c, p); }
   *c = &i; c = p;
   while (1 || (unsigned int)3 >= 0 || ((int)-1) == ((unsigned int)1));
-  return;
+  return 0;
   ;
   return 0;
 }

the patch does work. I found  the fvwm2's aclocal.m4 is contructed by
autoconf 2.68， but the autoconf in ports are 2.69,
so the configure patched by my patch is then reconstructed by the
autoconf, so does anyone has any other dear of how to
fixed the autoconf version mismatch