From 9aedd79729193d57939dd171850eb2d44d28eecb Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Thu, 1 Jan 2015 14:59:00 -0800 Subject: [PATCH 1/3] grep: avoid false-positive UMR For some inputs, valgrind would report an uninitialized memory read error, but it was harmless. * src/grep.c (fillbuf): Initialize those trailing bytes. --- src/grep.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/grep.c b/src/grep.c index 2276e93..c85fc6e 100644 --- a/src/grep.c +++ b/src/grep.c @@ -810,6 +810,12 @@ fillbuf (size_t save, struct stat const *st) fillsize = undossify_input (readbuf, fillsize); buflim = readbuf + fillsize; + + /* Initialize the following word, because skip_easy_bytes and some + matchers read (but do not use) those bytes. This avoids false + positive reports of these bytes being used uninitialized. */ + memset (buflim, 0, sizeof (uword)); + return cc; } -- 2.2.1