I see three distinct issues

1. Windows compile failure (many bots are affected):
https://build.chromium.org/p/chromium.fyi/builders/ClangToTWin/builds/8000

2. LLD failure:
https://build.chromium.org/p/chromium.fyi/builders/ClangToTLinuxLLD/builds/384

3. 'ClangToTLinux dbg' failure that might resolve itself after a new run:
https://build.chromium.org/p/chromium.fyi/builders/ClangToTLinux%20%28dbg%29/builds/3270

Before I saw the failures, I started to build r270823 on the bots:
https://codereview.chromium.org/2015793003/

While we are unlikely to roll this revision (LLD failure looks like an upstream bug), the results of the build might reveal new blockers.

The lld bot has never passed so I think we're fine to ignore it for the roll.

That's useful to know, thanks.

In the mean time, the packages are built:
https://codereview.chromium.org/2015793003/

ClangToTLinux (dbg) bot cycled green and we ignore LLD issue, so only Windows failures are to care. After a closer look, there're a few kinds of them:

1. Compile error about string literals:
https://build.chromium.org/p/chromium.fyi/builders/ClangToTWin/builds/8010

..\..\chrome\chrome_watcher\system_load_estimator.cc(97,39):  error: ISO C++11 does not allow conversion from string literal to 'wchar_t *' [-Werror,-Wwritable-strings]
      AddPdhCounter(pdh_query_.get(), L"LogicalDisk(C:)", L"% Idle Time");

2. Multiple browser tests failed:
https://build.chromium.org/p/chromium.fyi/builders/ClangToTWin64%20tester/builds/4873

None of them look as a toolchain issue.
I will take a closer look, when I am back from my morning commute chore.

1 is due to https://codereview.chromium.org/1986233002 and happens on the pinned bot too. I'm looking at that right now.

2 also happens on the pinned bots, but I'm hesitant to roll before understanding what's going on there. This is  bug 614745 

Ok, those are both understood now.

Thank you, Nico!
Can you please pick the archives from https://codereview.chromium.org/2015793003/ and deploy them on goma, please?

done

Thank you! Is the push process done yet?

Yes, the push seems to be finished.

I started try jobs (regular dry run + try bots listed in https://chromium.googlesource.com/chromium/src/+/master/docs/updating_clang.md)

Try bots are green all but the msan one: https://codereview.chromium.org/2015793003/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/709225ae8e282d53833e01e52d552d1178917951

commit 709225ae8e282d53833e01e52d552d1178917951
Author: krasin <krasin@google.com>
Date: Fri May 27 04:39:09 2016

Roll clang 269902:270823.

Ran `./tools/clang/scripts/upload_revision.py 270823`.

BUG= 614933 

Review-Url: https://codereview.chromium.org/2015793003
Cr-Commit-Position: refs/heads/master@{#396388}

[modify] https://crrev.com/709225ae8e282d53833e01e52d552d1178917951/tools/clang/scripts/update.py