------- Comment #1 from rbarreira at gmail dot com 2010-03-17 16:35 -------
Note that if you use scanf ("%llx", &a) and input "ffffffffffff" instead of
having a hardcoded value for a, the bug happens both with -O3 and -O0.
To sum up it seems that when the popcnt instruction is actually issued, it's
using a 32-bit instruction instead of 64-bit.
--
rbarreira at gmail dot com changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|__builtin_popcountll fails |__builtin_popcountll fails
|with -O0 and -mpopcnt |with -O0 and -mpopcnt
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43406
