Fixing bug described in patch #756032, where SRE reads invalid data
due to a corrupted end pointer.
diff --git a/Modules/_sre.c b/Modules/_sre.c
index 3f9a2d3..a8a9774 100644
--- a/Modules/_sre.c
+++ b/Modules/_sre.c
@@ -1297,7 +1297,7 @@
 
         flags = pattern[2];
 
-        if (pattern[3] > 0) {
+        if (pattern[3] > 1) {
             /* adjust end point (but make sure we leave at least one
                character in there, so literal search will work) */
             end -= pattern[3]-1;