FYI, we think that it would be better to have new build-bot for UBSan builds, because we already spend about ~2h for ASan and ~2h for MSan on one buildbot: https://build.chromium.org/p/chromium.fyi/buildslaves/slave43-c1

Also I can take this task if you are busy.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/277738b70c694a1017dfce3305badf4c319bed30

commit 277738b70c694a1017dfce3305badf4c319bed30
Author: aizatsky <aizatsky@chromium.org>
Date: Fri Mar 25 22:14:33 2016

[libfuzzer] separate libfuzzer ubsan configuration and ubsan build config setup.

BUG= 596650 
TBR=brettw@chromium.org

Review URL: https://codereview.chromium.org/1832213002

Cr-Commit-Position: refs/heads/master@{#383382}

[modify] https://crrev.com/277738b70c694a1017dfce3305badf4c319bed30/build/config/sanitizers/BUILD.gn
[modify] https://crrev.com/277738b70c694a1017dfce3305badf4c319bed30/build/config/sanitizers/sanitizers.gni
[modify] https://crrev.com/277738b70c694a1017dfce3305badf4c319bed30/tools/mb/mb_config.pyl

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/build.git/+/604b2fc4bcc2e465458f43d128686cf4f904948a

commit 604b2fc4bcc2e465458f43d128686cf4f904948a
Author: aizatsky@chromium.org <aizatsky@chromium.org>
Date: Fri Mar 25 22:19:26 2016

[libfuzzer] UBSan build configuration

BUG= 596650 

Review URL: https://codereview.chromium.org/1823423005

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/build@299497 0039d316-1c4b-4281-b951-d872f2087c98

[add] https://crrev.com/604b2fc4bcc2e465458f43d128686cf4f904948a/scripts/slave/recipes/chromium_libfuzzer.expected/full_chromium_fyi_Libfuzzer_Upload_Linux_UBSan.json
[modify] https://crrev.com/604b2fc4bcc2e465458f43d128686cf4f904948a/scripts/slave/recipes/chromium_libfuzzer.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/tools/build.git/+/04f6108c8cad0de19d87d564a470100e275df265

commit 04f6108c8cad0de19d87d564a470100e275df265
Author: aizatsky@chromium.org <aizatsky@chromium.org>
Date: Sat Mar 26 00:08:13 2016

[libfuzzer] registering ubsan build.

BUG= 596650 ,598097

Review URL: https://codereview.chromium.org/1836713002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/build@299499 0039d316-1c4b-4281-b951-d872f2087c98

[modify] https://crrev.com/04f6108c8cad0de19d87d564a470100e275df265/masters/master.chromium.fyi/master.cfg
[modify] https://crrev.com/04f6108c8cad0de19d87d564a470100e275df265/masters/master.chromium.fyi/slaves.cfg

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/abed7e64e8b0e13e2b66dc1c7ccfdc478ca73e93

commit abed7e64e8b0e13e2b66dc1c7ccfdc478ca73e93
Author: aizatsky <aizatsky@chromium.org>
Date: Mon Mar 28 23:05:15 2016

[libfuzzer] tweaking is_ubsan_security options.

BUG= 596650 

Review URL: https://codereview.chromium.org/1839753003

Cr-Commit-Position: refs/heads/master@{#383594}

[modify] https://crrev.com/abed7e64e8b0e13e2b66dc1c7ccfdc478ca73e93/build/config/BUILD.gn
[modify] https://crrev.com/abed7e64e8b0e13e2b66dc1c7ccfdc478ca73e93/build/config/sanitizers/BUILD.gn
[modify] https://crrev.com/abed7e64e8b0e13e2b66dc1c7ccfdc478ca73e93/build/config/sanitizers/sanitizers.gni

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e61554d35d887153220d0ac711c6e77e0f3878c2

commit e61554d35d887153220d0ac711c6e77e0f3878c2
Author: aizatsky <aizatsky@chromium.org>
Date: Mon Mar 28 23:57:21 2016

[libfuzzer] disable nacl in all libfuzzer builds

BUG= 596650 

Review URL: https://codereview.chromium.org/1834223003

Cr-Commit-Position: refs/heads/master@{#383616}

[modify] https://crrev.com/e61554d35d887153220d0ac711c6e77e0f3878c2/tools/mb/mb_config.pyl

Max, the bot is up and running, the build is green. Please add it to CF.

Awesome! Thanks!

I set up ubsan job to be running at 10 bots. Will check logs and then expand the job to 100-200 bots.

Example: https://paste.googleplex.com/5480163756212224
We do not crash when UBSan detects anything right now, correct?

For first 642 runs we've got about 3769 UBSan alerts. I think I should enable crashing by default and should not increase number of bots significantly just to avoid too many crashes.

Enabled halt_on_error=1, still 10 bots running, let's see.

The following revision refers to this bug:
  http://goto.ext.google.com/viewvc/chrome-internal?view=rev&revision=86097

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r86097 | mmoroz@google.com | 2016-04-04T16:18:29.513526Z

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The following revision refers to this bug:
  http://goto.ext.google.com/viewvc/chrome-internal?view=rev&revision=86252

------------------------------------------------------------------
r86252 | mmoroz@google.com | 2016-04-07T10:32:54.162790Z

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Thanks everyone for taking part in this. First bugs are filed:

https://bugs.chromium.org/p/chromium/issues/list?can=2&q=stability%3DUndefinedBehaviorSanitizer&colspec=ID+Pri+M+Stars+ReleaseBlock+Component+Status+Owner+Summary+OS+Modified&x=m&y=releaseblock&cells=ids

I'm increasing number of bots to 100.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0c5c82d091b1dae3b03961a7048b0e7f6249abcd

commit 0c5c82d091b1dae3b03961a7048b0e7f6249abcd
Author: aizatsky <aizatsky@chromium.org>
Date: Mon Apr 18 22:34:43 2016

[libfuzzer] adding ubsan to the list of supported configurations.

BUG= 596650 

Review URL: https://codereview.chromium.org/1899933002

Cr-Commit-Position: refs/heads/master@{#388057}

[modify] https://crrev.com/0c5c82d091b1dae3b03961a7048b0e7f6249abcd/testing/libfuzzer/getting_started.md