PATCH: [perl #126141]: qr/]]]]][\\/ fails to raise error

This was due to the trailing \ trying to look at the next character
without verifying that one actually existed.

1 files changed, 5 insertions, 0 deletions

diff --git a/regcomp.c b/regcomp.c
index 9b63fef168..68c599f118 100644
--- a/regcomp.c
+++ b/regcomp.c
@@ -15718,6 +15718,11 @@ S_regclass(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth,
         }
         else if (value == '\\') {
             /* Is a backslash; get the code point of the char after it */
+
+            if (RExC_parse >= RExC_end) {
+                vFAIL("Unmatched [");
+            }
+
 	    if (UTF && ! UTF8_IS_INVARIANT(UCHARAT(RExC_parse))) {
 		value = utf8n_to_uvchr((U8*)RExC_parse,
 				   RExC_end - RExC_parse,