[PATCH] [libc++] Allow libc++ to be built on systems without POSIX threads

[Jon Roelofs]

================
Comment at: sources/cxx-stl/llvm-libc++/libcxx/src/thread.cpp:129
@@ +128,3 @@
+#else
+#warning sleep_for not yet implemented
+#endif
----------------
This ought to get moved to http://reviews.llvm.org/D4045 (i.e. place sleep_for inside a _LIBCPP_HAS_MONOTONIC_CLOCK)

http://reviews.llvm.org/D3969