Hack around TLS destructors firing after the process exits

Hack around TLS destructors firing after the process exits

- When a process exits on Windows, Windows closes all handles
- Our mutexes use a handle to a semaphore for locking

- If our TLS destructors need to take a lock during thread exit (but after process has started to shutdown) we will deadlock waiting on a handle that's been closed.

This works around the problem by not running tls destructors when we are exiting the process.

R=zra@google.com

Committed: https://github.com/dart-lang/sdk/commit/237702c6b5e2b312cf5394e17396744231742374

[Cutch, 2015-11-03 22:45:12]

Description was changed from

==========
Hack around TLS destructors firing after the process exits

BUG=
==========

to

==========
Hack around TLS destructors firing after the process exits

BUG=
==========

[Cutch, 2015-11-03 22:45:12]

johnmccutchan@google.com changed reviewers:
+ zra@google.com

[zra, 2015-11-03 22:55:13]

lgtm

Could you also add a note for posterity in the CL description explaining why
this hack is needed.

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/platform_win.cc
File runtime/bin/platform_win.cc (right):

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/platform_win.cc...
runtime/bin/platform_win.cc:18: // Defined in os_thread_win.cc
vm/os_thread_win.cc

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/run_vm_tests.cc
File runtime/bin/run_vm_tests.cc (right):

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/run_vm_tests.cc...
runtime/bin/run_vm_tests.cc:13: #include "vm/unit_test.h"
Since we're here we may as well sort these, if possible.

https://codereview.chromium.org/1416063005/diff/1/runtime/vm/os_thread_win.cc
File runtime/vm/os_thread_win.cc (right):

https://codereview.chromium.org/1416063005/diff/1/runtime/vm/os_thread_win.cc...
runtime/vm/os_thread_win.cc:17: // This flag is flipped by platform_win.cc when
the process is exiting.
Please add a TODO for me to try removing when shutdown is enabled.

[Cutch, 2015-11-03 23:02:05]

Description was changed from

==========
Hack around TLS destructors firing after the process exits

BUG=
==========

to

==========
Hack around TLS destructors firing after the process exits

- When a process exits on Windows, Windows closes all handles
- Our mutexes use a handle to a semaphore for locking

- If our TLS destructors need to take a lock during thread exit (but after
process has started to shutdown) we will deadlock waiting on a handle that's
been closed.

This works around the problem by not running tls destructors when we are exiting
the process.
==========

[Cutch, 2015-11-03 23:02:24]

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/platform_win.cc
File runtime/bin/platform_win.cc (right):

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/platform_win.cc...
runtime/bin/platform_win.cc:18: // Defined in os_thread_win.cc
On 2015/11/03 22:55:12, zra wrote:
> vm/os_thread_win.cc

Done.

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/run_vm_tests.cc
File runtime/bin/run_vm_tests.cc (right):

https://codereview.chromium.org/1416063005/diff/1/runtime/bin/run_vm_tests.cc...
runtime/bin/run_vm_tests.cc:13: #include "vm/unit_test.h"
On 2015/11/03 22:55:12, zra wrote:
> Since we're here we may as well sort these, if possible.

Done.

https://codereview.chromium.org/1416063005/diff/1/runtime/vm/os_thread_win.cc
File runtime/vm/os_thread_win.cc (right):

https://codereview.chromium.org/1416063005/diff/1/runtime/vm/os_thread_win.cc...
runtime/vm/os_thread_win.cc:17: // This flag is flipped by platform_win.cc when
the process is exiting.
On 2015/11/03 22:55:12, zra wrote:
> Please add a TODO for me to try removing when shutdown is enabled.

Done.

[Cutch, 2015-11-03 23:02:43]

Committed patchset #2 (id:20001) manually as
237702c6b5e2b312cf5394e17396744231742374 (presubmit successful).