atomic: Check for __sync_val_compare_and_swap instead of __sync_synchronize
authorMartin Storsjö <martin@martin.st>
Fri, 8 Mar 2013 10:32:38 +0000 (12:32 +0200)
committerMartin Storsjö <martin@martin.st>
Fri, 8 Mar 2013 12:55:08 +0000 (14:55 +0200)
commite460aa3282962aa3e89f19e207ec13b501187949
treea15c4bd09b2609b086ed9fd6e74127af52e53978
parentf1af3d19a7924c6f5963ee15a83bad26d2262dc3
atomic: Check for __sync_val_compare_and_swap instead of __sync_synchronize

Not all gcc configurations have an implementation of all the atomic
operations, and some gcc configurations have some atomic builtins
implemented but not all.

Thus check for the most essential function, whose presence should
indicate that all others are present as well, since it can be used
to implement all the other ones.

Signed-off-by: Martin Storsjö <martin@martin.st>
configure
libavutil/atomic.c
libavutil/atomic.h