[PATCH] Run the callback on a separate stack in StopTheWorld.

[Alexey Samsonov]

================
Comment at: lib/sanitizer_common/sanitizer_stoptheworld_linux.cc:281
@@ -259,1 +280,3 @@
   // which modify errno (which is shared between the two threads).
+  sigset_t blocked_sigset;
+  sigset_t old_sigset;
----------------
We've turned these into globals because sanitizer tools (well, TSan) have strict limitations on the stack frame size (512 bytes). sizeof(sigset_t) and sizeof(old_sigactions) are large enough. To test your changes:
$ cd projects/compiler-rt/lib/tsan
$ make -f Makefile.old presubmit


http://llvm-reviews.chandlerc.com/D592