[Bug libstdc++/51798] [4.7 regression] libstdc++ atomicity performance regression due to __sync_fetch_and_add

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51798

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-01-25 14:08:41 UTC ---
At least at this point I'd feel much safer if libstdc++ used just acq_rel
semantics for the all atomic_fetch_and_add places, instead of somewhere acq and
somewhere rel semantics.