pcre_exec(): Andrew Kuchling's patch for pcre memory leak.
diff --git a/Modules/pypcre.c b/Modules/pypcre.c
index 9c6939f..976eb21 100644
--- a/Modules/pypcre.c
+++ b/Modules/pypcre.c
@@ -4746,6 +4746,7 @@
 printf(">>>> returning %d\n", match_block.errorcode);
 #endif
 
+ free_stack(&match_block); 
  return match_block.errorcode;
 }