From: Andrew M. Kuchling <amk@amk.ca>
Date: Tue, 5 Aug 2008 01:38:08 +0000 (+0000)
Subject: #3367 from Kristjan Valur Jonsson:
X-Git-Tag: v2.6b3~128
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=efa61bc15f325bb94d147b8641031d1774fb7a5c;p=thirdparty%2FPython%2Fcpython.git

#3367 from Kristjan Valur Jonsson:
If a PyTokenizer_FromString() is called with an empty string, the
tokenizer's line_start member never gets initialized.  Later, it is
compared with the token pointer 'a' in parsetok.c:193 and that behavior
can result in undefined behavior.
---

diff --git a/Parser/tokenizer.c b/Parser/tokenizer.c
index 1d0a4aa3f23b..73ff92a19939 100644
--- a/Parser/tokenizer.c
+++ b/Parser/tokenizer.c
@@ -1117,7 +1117,7 @@ tok_get(register struct tok_state *tok, char **p_start, char **p_end)
 	register int c;
 	int blankline;
 
-	*p_start = *p_end = NULL;
+	tok->line_start = *p_start = *p_end = NULL;
   nextline:
 	tok->start = NULL;
 	blankline = 0;