Fixes #9720
Fixes #8053
Fixes https://code.google.com/p/thread-sanitizer/issues/detail?id=89
Change-Id: I7d598e53de86586bb9702d8e9276a4d6aece2dfc
Reviewed-on: https://go-review.googlesource.com/4950
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Tested with gcc 4.6.1 and 4.7.0. On Windows it's built with 64-bit MinGW.
-Current runtime is built on rev 215000.
+Current runtime is built on rev 229396.