Shifting a 32bit value by 32 is undefined.
Instead of using shifts to create the mask, explicitly create it by subtracting 1 from the signbit value (and using bitwise NOT to fill all the higher bits).
This commit looks confusing because Jef wanted me to not have two places where I use the bitwise not. So instead of creating an equivalent mask variable and not having to change the return statements we end up with a mask that is the bitwise invert of what was there before this commit and therefore the return statements need to change as well.
Coverity CID 207769
Suggested-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Dirk Hohndel dirk@hohndel.org --- src/uwatec_smart_parser.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/src/uwatec_smart_parser.c b/src/uwatec_smart_parser.c index a70acb7b91c6..bd715b03cf52 100644 --- a/src/uwatec_smart_parser.c +++ b/src/uwatec_smart_parser.c @@ -886,15 +886,15 @@ uwatec_smart_fixsignbit (unsigned int x, unsigned int n) return 0;
unsigned int signbit = (1 << (n - 1)); - unsigned int mask = (0xFFFFFFFF << n); + unsigned int mask = (signbit - 1);
// When turning a two's-complement number with a certain number // of bits into one with more bits, the sign bit must be repeated // in all the extra bits. if ((x & signbit) == signbit) - return x | mask; + return x | ~mask; else - return x & ~mask; + return x & mask; }