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

[dje at gcc dot gnu.org]

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

--- Comment #15 from David Edelsohn <dje at gcc dot gnu.org> 2012-01-26 
19:42:47 UTC ---
> calm down, a few places in libstdc++ use __sync_compare_and_swap directly
> because there is no CAS in atomicity.h

Jonathan,

I do not know what you are reading into my comment.  This has nothing to do
with calmness, it is a statement of fact.  If more places in libstdc++ use
__sync intrinsics directly, then more places have regressed. It is unfortunate
that the current implementation of libstdc++ did not localize the use of those
intrinsics.