Fix historic C99 incompatibility in autoconf-generated C code.  No

need to upstream this because the issue goes away once upstream

re-runs autoconf as part of the next release.

diff --git a/configure b/configure

index 31b11325d1896f30..c1feba66f9eb3510 100755

--- a/configure

+++ b/configure

@@ -2653,7 +2653,7 @@ if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5

   echo "$as_me:$LINENO: \$? = $ac_status" >&5

   (exit $ac_status); }; }; then

   for ac_declaration in \

-   '' \

+   '#include <stdlib.h>' \

    'extern "C" void std::exit (int) throw (); using std::exit;' \

    'extern "C" void std::exit (int); using std::exit;' \

    'extern "C" void exit (int) throw ();' \

@@ -6363,8 +6363,8 @@ main ()

   for (i = 0; i < 256; i++)

     if (XOR (islower (i), ISLOWER (i))

 	|| toupper (i) != TOUPPER (i))

-      exit(2);

-  exit (0);

+      return 2;

+  return 0;

 }

 _ACEOF

 rm -f conftest$ac_exeext