From 6a5a3037b4f6ab7807c59c351d1064d3515ef269 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Mon, 23 Jun 2014 13:23:47 +0100
Subject: [PATCH] avoid getting stuck on non-UTF-8 symbol encodings in bytecode

Found by fuzz tester, and this bug seems to be a common reason for
the fuzz test to time out.
---
 racket/src/racket/src/symbol.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/racket/src/racket/src/symbol.c b/racket/src/racket/src/symbol.c
index 9068fdd366..41b031e670 100644
--- a/racket/src/racket/src/symbol.c
+++ b/racket/src/racket/src/symbol.c
@@ -611,11 +611,11 @@ const char *scheme_symbol_name_and_size(Scheme_Object *sym, uintptr_t *length, i
     if (ch > 127) {
       /* Decode UTF-8. */
       mzchar buf[2];
-      int ul = 2;
+      int ul = 1;
       while (1) {
         if (scheme_utf8_decode((unsigned char *)s, i, i + ul,
                                buf, 0, 1,
-                               NULL, 0, 0) > 0)
+                               NULL, 0, '?') > 0)
           break;
         ul++;
       }