We can fix https://llvm.org/pr38857 if we pick up r343603.

I'm going to make clang packages without a fix for issue 891320, which is a crash in code coverage. It's a clang bug, but mmoroz@ reverted the chromium cl that uncovered it for now. A proper compiler fix will wait for the next one.

I reverted David Major's NtTerminateThread thing again and kicked off some packages: https://chromium-review.googlesource.com/c/chromium/src/+/1265122

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4b0d30529e9fe28989bb37680bd6e26fae4546df

commit 4b0d30529e9fe28989bb37680bd6e26fae4546df
Author: Reid Kleckner <rnk@google.com>
Date: Tue Oct 09 14:47:39 2018

Roll clang 343342:343880.

Ran `./tools/clang/scripts/upload_revision.py 343880 1`.

Bug:  891181 
Change-Id: I257609c2455b25ce9229dbb90fd451e035165a58
Reviewed-on: https://chromium-review.googlesource.com/c/1265122
Commit-Queue: Reid Kleckner <rnk@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#597910}
[modify] https://crrev.com/4b0d30529e9fe28989bb37680bd6e26fae4546df/tools/clang/scripts/update.py

Next roll:  Issue 893935 

Looks like it stuck. In any case, we did a follow-up roll.