Since this is a linker warning, I think we can simply ignore them with USE="asan" as long as chrome builds.

instead of building the "world" on the fuzzer bot, how about we switch to your new virtual/target-fuzzer ?  building Chrome in the first place is a waste of time.

I had proposed that in my doc before we decided to build the whole base image. It would make builds much faster as well.

Tried creating a virtual/target-os package in fuzzer profile directory but it is not picked up (Because it is a profile?). And changing the amd64-generic board does not look like an option since it will impact all other amd64-generic builds.

How to proceed, should I just fix the chrome build?

CL below creates a masked target-os build that the fuzzer profile should unmask:
https://chromium-review.googlesource.com/c/chromiumos/overlays/board-overlays/+/971470

i was thinking of updating the builder config to build the virtual instead.  look at chromite/cbuildbot/chromeos_config.py and the configs that set packages=[].

that would also shrink the sysroot we upload to the fuzzer as it'd only contain the fuzzers and packages it cares about.

Will try restricting to builder config.

I also think that the CL is still useful for local builds. e.g. running ./build_packages without extra arguments. Otherwise, it might be confusing for devs.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/8bb4ff56c078dd1237dda082eb67a29065f43eac

commit 8bb4ff56c078dd1237dda082eb67a29065f43eac
Author: Manoj Gupta <manojgupta@google.com>
Date: Wed Mar 21 02:30:10 2018

midis: Add deps on media-libs/alsa-lib.

midis fails to build when only building virtual/target-fuzzers
because of missing alsa dependency.

BUG= chromium:823787 
TEST=./build_packages virtual/target-fuzzers work.

Change-Id: I3c87ed64bc4bd636516d017eb4d144d5a95867d3
Reviewed-on: https://chromium-review.googlesource.com/972157
Commit-Ready: Manoj Gupta <manojgupta@chromium.org>
Tested-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>

[modify] https://crrev.com/8bb4ff56c078dd1237dda082eb67a29065f43eac/chromeos-base/midis/midis-9999.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/chromite/+/8bf5a724397cd15569d5da6a529a7b044b28d137

commit 8bf5a724397cd15569d5da6a529a7b044b28d137
Author: Manoj Gupta <manojgupta@google.com>
Date: Thu Mar 22 01:30:40 2018

cbuildbot: Only build virtual/target-fuzzers for fuzzer builders.

We are not interested in building most of the Chrome OS packages
when building fuzzers.

BUG= chromium:823787 
TEST=smaller sysroot containing the fuzzers is uploaded.

Change-Id: I6863516f88b3fa2fc82ddfa5b6852c509c672bdd
Reviewed-on: https://chromium-review.googlesource.com/971768
Commit-Ready: Manoj Gupta <manojgupta@chromium.org>
Tested-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Caroline Tice <cmtice@chromium.org>

[modify] https://crrev.com/8bf5a724397cd15569d5da6a529a7b044b28d137/cbuildbot/chromeos_config.py
[modify] https://crrev.com/8bf5a724397cd15569d5da6a529a7b044b28d137/cbuildbot/stages/generic_stages.py
[modify] https://crrev.com/8bf5a724397cd15569d5da6a529a7b044b28d137/cbuildbot/stages/artifact_stages.py
[modify] https://crrev.com/8bf5a724397cd15569d5da6a529a7b044b28d137/cbuildbot/config_dump.json
[modify] https://crrev.com/8bf5a724397cd15569d5da6a529a7b044b28d137/cbuildbot/stages/build_stages.py
[modify] https://crrev.com/8bf5a724397cd15569d5da6a529a7b044b28d137/lib/constants.py

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d000ba8fdded914995828078611e361e96f7d722

commit d000ba8fdded914995828078611e361e96f7d722
Author: chromite-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com <chromite-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Date: Thu Mar 22 03:25:05 2018

Roll src/third_party/chromite/ 1d37d531d..8bf5a7243 (3 commits)

https://chromium.googlesource.com/chromiumos/chromite.git/+log/1d37d531d536..8bf5a724397c

$ git log 1d37d531d..8bf5a7243 --date=short --no-merges --format='%ad %ae %s'
2018-03-20 manojgupta cbuildbot: Only build virtual/target-fuzzers for fuzzer builders.
2018-03-15 dgarrett archive_lib: Stop appending trybot- for tryjobs.
2018-03-21 dgarrett precq_launcher: Fix swarming PreCQ hack.

Created with:
  roll-dep src/third_party/chromite
BUG= chromium:823787 , chromium:667393 , chromium:823445 


The AutoRoll server is located here: https://chromite-chromium-roll.skia.org

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.


TBR=chrome-os-gardeners@chromium.org

Change-Id: I7abe614767178c4d769dd22efaa488e7e6e9083e
Reviewed-on: https://chromium-review.googlesource.com/974743
Reviewed-by: Chromite Chromium Autoroll <chromite-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: Chromite Chromium Autoroll <chromite-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#544964}
[modify] https://crrev.com/d000ba8fdded914995828078611e361e96f7d722/DEPS

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/951c27af04bf26205ea72a105f516bcd53348eac

commit 951c27af04bf26205ea72a105f516bcd53348eac
Author: Manoj Gupta <manojgupta@google.com>
Date: Tue Apr 03 03:12:52 2018

fuzzing: Build all platform packages with fuzzer flags.

Add helper function to add fuzzing flags. Call this
in platform class to ensure that all platform packages
are built with libfuzzer coverage with USE="fuzzer".

Also update libchrome and libmojo to call fuzzer setup.

BUG= chromium:823787 
TEST=USE="asan fuzzer" emerge-$BOARD virtual/target-fuzzers work.

Change-Id: I20900ccf746399fbca3f3835fdeb1222a3fd4054
Reviewed-on: https://chromium-review.googlesource.com/989393
Commit-Ready: Manoj Gupta <manojgupta@chromium.org>
Tested-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Caroline Tice <cmtice@chromium.org>

[rename] https://crrev.com/951c27af04bf26205ea72a105f516bcd53348eac/chromeos-base/libmojo/libmojo-395517-r4.ebuild
[modify] https://crrev.com/951c27af04bf26205ea72a105f516bcd53348eac/chromeos-base/libchrome/libchrome-395517.ebuild
[modify] https://crrev.com/951c27af04bf26205ea72a105f516bcd53348eac/chromeos-base/libmojo/libmojo-395517.ebuild
[modify] https://crrev.com/951c27af04bf26205ea72a105f516bcd53348eac/eclass/platform.eclass
[modify] https://crrev.com/951c27af04bf26205ea72a105f516bcd53348eac/eclass/toolchain-funcs.eclass
[rename] https://crrev.com/951c27af04bf26205ea72a105f516bcd53348eac/chromeos-base/libchrome/libchrome-395517-r26.ebuild