Signed int values were being used where the original code used uint32_t types:
http://www.azillionmonkeys.com/qed/hash.html Right shifting negative int values has implementation-defined and left shifting has undefined behavior. On my platform (x86_64) right shifting was doing sign extension and filling high bits with 1s, which is different than the original algorithm. Signed-off-by: Michael Sartain <mikes...@fastmail.com> --- trace-hash-local.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/trace-hash-local.h b/trace-hash-local.h index b2a1002..b3f9b06 100644 --- a/trace-hash-local.h +++ b/trace-hash-local.h @@ -22,7 +22,7 @@ static inline unsigned int trace_hash(int val) { - int hash, tmp; + unsigned int hash, tmp; hash = 12546869; /* random prime */ @@ -34,7 +34,7 @@ static inline unsigned int trace_hash(int val) */ hash += (val & 0xffff); - tmp = (val >> 16) ^ hash; + tmp = ((unsigned int)val >> 16) ^ hash; hash = (hash << 16) ^ tmp; hash += hash >> 11; -- 2.13.2
