[Bug libstdc++/51906] thread lock test failures on darwin11 under Xcode 4.2

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51906

--- Comment #16 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-01-29 
00:42:38 UTC ---
(In reply to comment #14)
> I'm not having much luck getting the test case to compile on darwin11.

Did you use -std=c++0x? (or -std=c++11)