Non-deterministic test hangs introduced recently?

Hi everyone,

Is anyone else seeing LLDB tests hang as of late? I built this morning's trunk on Mac OS X and saw LibcxxVectorDataFormatterTestCase hang indefinitely. After killing the tests and running them again, I am getting a little bit further.

The Linux buildbots are also seeing tests hang, but oddly enough I'm unable to reproduce the results on Linux locally. According to the logs the bots started hanging at the build of revisions r179327, r179328, r179329. gribozavr_ (from IRC) was able to capture this stack trace from a hanging Linux test http://pastebin.com/gNieQhWX

In my case (the hang on Mac OS X Mnt Lion) I was able to capture the following stack trace from the dotest.py process: pastebin.com/au1GKM2S<http://pastebin.com/au1GKM2S&gt; and the following trace from the debugserver: thread #1: tid = 0x1c03, 0x00007fff91fad0fa libsystem_kernel.dylib`__psynch_cvwa - Pastebin.com

Any help, even just confirming that this is in fact a problem that you're seeing, would be appreciated. Hopefully we can squash this bug soon, as I imagine it might block more than just this developer.

Thanks,
Dan

Here is a backtrace of all the threads (from the same person).

http://pastebin.com/bF0EW8Cj

Regards,

  Filipe