this is also happening in the LLVM builder.
https://uberchromegw.corp.google.com/i/chromeos/builders/llvm-toolchain-group/builds/75

This is interesting. Why is xorg built in CrOS?

Although also failed in platform_ToolchainOptions, x86-alex failed for other reasons (LOAD Writable and Exec).

The mali driver RDEPEND on xorg-server.

It failed in daisy because xorg-server is built with -z,lazy which overrides ldwrapper.hardened:

# hardened ldflags
[[ ${PN} = xorg-server || -n ${DRIVER} ]] && append-ldflags -Wl,-z,lazy

https://chromium.googlesource.com/chromiumos/overlays/portage-stable/+/master/eclass/xorg-2.eclass#428

This is the same as upstream. I'm not sure why they considered -Wl,-z,lazy as hardened flags.

Or maybe this is intended to undo the hardening flags -Wl,-z,now which might has some problems with the library. If that is the case, we might simply add them to the white list.

The xorg libraries are already in now_whitelist_x. However, daisy had switched to freon so now_whitelist is used.

This seems to be a problem in overlays/overlay-daisy/media-libs/mali-drivers-bin/mali-drivers-bin-1.20-r192.ebuild

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/autotest/+/bfaa1ce312a54155d4de18fc9923d8f72ba14b4f

commit bfaa1ce312a54155d4de18fc9923d8f72ba14b4f
Author: Ting-Yuan Huang <laszio@chromium.org>
Date: Sat May 28 08:36:00 2016

platform_ToolchainOptions: mesa uses writable text for performance

autoconf option glx-read-only-text is disabled by default.

BUG= chromium:614756 
TEST=passed on x86-alex

Change-Id: Idbe968f13e2b1f9ad1bb4ad151d5ad3e7fb1d415
Reviewed-on: https://chromium-review.googlesource.com/348110
Commit-Ready: Ting-Yuan Huang <laszio@chromium.org>
Tested-by: Ting-Yuan Huang <laszio@chromium.org>
Reviewed-by: Caroline Tice <cmtice@chromium.org>

[modify] https://crrev.com/bfaa1ce312a54155d4de18fc9923d8f72ba14b4f/client/site_tests/platform_ToolchainOptions/loadwx_whitelist
[modify] https://crrev.com/bfaa1ce312a54155d4de18fc9923d8f72ba14b4f/client/site_tests/platform_ToolchainOptions/loadwx_whitelist_x

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/c8e2d581a2eb2761b5d276fe9b777f369558e0dd

commit c8e2d581a2eb2761b5d276fe9b777f369558e0dd
Author: Ting-Yuan Huang <laszio@chromium.org>
Date: Sat May 28 07:39:00 2016

daisy: Avoid building x11 drivers when X is not used.

BUG= chromium:614756 
TEST=cbuildbot --hwtest ... daisy-release

Change-Id: I765d97ef4392b06f3172a8793cdfdb05248f90d3
Reviewed-on: https://chromium-review.googlesource.com/348101
Commit-Ready: Ting-Yuan Huang <laszio@chromium.org>
Tested-by: Ting-Yuan Huang <laszio@chromium.org>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>

[rename] https://crrev.com/c8e2d581a2eb2761b5d276fe9b777f369558e0dd/overlay-daisy/chromeos-base/chromeos-bsp-daisy/chromeos-bsp-daisy-0.0.2-r4.ebuild
[modify] https://crrev.com/c8e2d581a2eb2761b5d276fe9b777f369558e0dd/overlay-daisy/chromeos-base/chromeos-bsp-daisy/chromeos-bsp-daisy-0.0.2.ebuild

The builder turned green after all platform_ToolchainOptions issues were fixed:

https://uberchromegw.corp.google.com/i/chromeos/builders/gcc-toolchain-group/builds/27

However, there are some retried tests. Let's leave this bug open for a few more days.

Issue 610659 has been merged into this issue.

Marking this fixed since the original reasons that caused failing are resolved. Will file more specific bugs for new problems that block gcc-toolchain-group.