http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51258
--- Comment #18 from Jack Howarth <howarth at nitro dot med.uc.edu> 2011-12-06 20:53:35 UTC --- The actual binaries for atomic-load-int128.c at -O1 and higher run fine on x86_64-apple-darwin64 at -m64. However they take around 16 seconds to execute on a... Model Name: Mac Pro Model Identifier: MacPro3,1 Processor Name: Quad-Core Intel Xeon Processor Speed: 2.8 GHz Number of Processors: 2 Total Number of Cores: 8 L2 Cache (per Processor): 12 MB Memory: 12 GB Bus Speed: 1.6 GHz Increasing the timeout to 20 seconds allows all of the gcc.dg/simulate-thread/atomic-load-int128.c tests to pass.