1 files changed, 1 insertions, 1 deletions
diff --git a/regex.c b/regex.c
index faf38965..4ad34dcf 100644
--- a/regex.c
+++ b/regex.c
@@ -2579,7 +2579,7 @@ val read_until_match(val regex, val stream_in, val include_match_in)
 
   if (nil) {
 out_match:
-    while (stack != match)
+    while (stack && stack != match)
       unget_char(rcyc_pop(&stack), stream);
     if (!out)
       out = null_string;