I cannot reproduce this with dbus_unittests built with GN args target_cpu="x86".
How did you build 32-bit dbus_unittests?
Could you paste the log to see how it's failing?

BTW, are we still supporting Ubuntu 12.04 as a developer environment?

Please clarify with dpranke@ for the details about Ubuntu 12.04 support.

My exact gn args are

is_component_build = true
is_debug = true
use_goma = true
#gdb_index = true
target_cpu = "x86"


The failure I get is

thomasanderson@thomasanderson-VirtualBox:~/Developer/chromium_x86/src$ out/Debug/dbus_unittests --gtest_filter=EndToEndAsyncTest.TimeoutWithErrorCallback:EndToEndAsyncTest.CancelPendingCalls
IMPORTANT DEBUGGING NOTE: batches of tests are run inside their
own process. For debugging a test inside a debugger, use the
--gtest_filter=<your_test_name> flag along with
--single-process-tests.
Using sharding settings from environment. This is shard 0/1
Using 1 parallel jobs.
Note: Google Test filter = EndToEndAsyncTest.TimeoutWithErrorCallback:EndToEndAsyncTest.CancelPendingCalls
[==========] Running 2 tests from 1 test case.
[----------] Global test environment set-up.
[----------] 2 tests from EndToEndAsyncTest
[ RUN      ] EndToEndAsyncTest.TimeoutWithErrorCallback
[       OK ] EndToEndAsyncTest.TimeoutWithErrorCallback (149 ms)
[ RUN      ] EndToEndAsyncTest.CancelPendingCalls
CancelPendingCalls
../../dbus/end_to_end_async_unittest.cc:451: Failure
Value of: response_strings_.empty()
  Actual: false
Expected: true
[  FAILED  ] EndToEndAsyncTest.CancelPendingCalls (28 ms)
[----------] 2 tests from EndToEndAsyncTest (187 ms total)

[----------] Global test environment tear-down
[==========] 2 tests from 1 test case ran. (187 ms total)
[  PASSED  ] 1 test.
[  FAILED  ] 1 test, listed below:
[  FAILED  ] EndToEndAsyncTest.CancelPendingCalls

 1 FAILED TEST
[0520/101941:ERROR:kill_posix.cc(82)] Unable to terminate process group 12734: No such process
[1/2] EndToEndAsyncTest.TimeoutWithErrorCallback (149 ms)
[2/2] EndToEndAsyncTest.CancelPendingCalls (28 ms)
1 test failed:
    EndToEndAsyncTest.CancelPendingCalls (../../dbus/end_to_end_async_unittest.cc:424)
Tests took 0 seconds.

Yes, we still support 12.04.

Sorry I couldn't reproduce this locally with GN args you provided on 64-bit Ubuntu 14.04, with libdbus-1-3 whose version is 1.6.18-0ubuntu4.3.

As no bot is failing on build.chromium.org, I cannot be sure if our code is wrong or something in your running environment is wrong.

hashimoto@ I just tested again and found that my VM must also have a single cpu for the test to fail.  I'll try to fiddle with the timeouts to see if I can get it passing locally.