MFC r336113:
gzip: fix for undefined behavior.
Unportable left shift reported with MKSANITIZER=yes
USE_SANITIZER=undefined:
# progress -zf ./games.tgz tar -xp -C "./" -f -
/public/src.git/usr.bin/gzip/gzip.c:2126:33: runtime error: left shift of
251 by 24 places cannot be represented in type 'int'
100%
|****************************************************************************************************************|
44500 KiB 119.69 MiB/s 00:00 ETA
Refactor the following code into something that is more clear
and fix signed integer shift, by casting all buf[] elements to
(unsigned int):
unsigned char buf[8];
uint32_t usize;
[...]
else {
usize = buf[4] | buf[5] << 8 |
buf[6] << 16 | buf[7] << 24;
[...]
New version:
usize = buf[4];
usize |= (unsigned int)buf[5] << 8;
usize |= (unsigned int)buf[6] << 16;
usize |= (unsigned int)buf[7] << 24;
Only the "<< 24" part needs explicit cast, but for consistency make the
integer promotion explicit and clear to a code reader.
Sponsored by <The NetBSD Foundation>
Obtained from: NetBSD (CVS rev. 1.113)
UnifiedSplitRaw
