Create MSan config for Chromium recipe module + add WebRTC MSan recipe.

scripts/slave/recipe_modules/chromium/config.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import pipes
 
 from slave.recipe_config import config_item_context, ConfigGroup
 from slave.recipe_config import Dict, List, Single, Static, Set, BadConf
 from slave.recipe_config_types import Path
 
@@ skipping 315 matching lines @@
   if c.TARGET_PLATFORM == 'linux':
     c.gyp_env.GYP_DEFINES['use_allocator'] = 'none'
 
   c.gyp_env.GYP_DEFINES['asan'] = 1
   c.gyp_env.GYP_DEFINES['lsan'] = 1
 
 @config_ctx()
 def no_lsan(c):
   c.gyp_env.GYP_DEFINES['lsan'] = 0
 
+@config_ctx()
+def msan(c):
+  gyp_defs = c.gyp_env.GYP_DEFINES
+  gyp_defs['msan'] = 1
+  gyp_defs['msan_track_origins'] = 0

[earthdok, 2014/09/29 13:25:08]

msan_track_origins=0 should not be a part of the config. This option should be
chosen individually for each bot configuration as it has a significant impact on
performance. We already set a default value for it in common.gypi (currently 1).

[kjellander_chromium, 2014/09/30 10:56:40]

That makes sense, I left that variable in the existing config and used the
default for WebRTC in PS#2.

+  gyp_defs['use_instrumented_libraries'] = 1

[earthdok, 2014/09/29 13:25:08]

I'm also against adding instrumented libraries to the msan config, because
certain configurations do not need them. For example, we plan to have an MSan
bot for PDFium, which has no DSO dependencies.

Can you factor out those settings to a separate config 'instrumented_libraries',
and then apply it to the recipe using chromium_apply_config? Another benefit of
this arrangement is that it allows us to use instrumented libraries with other
sanitizers.

(Note that I don't actually know what chromium_apply_config does, just guessing
from the name.)

[kjellander_chromium, 2014/09/30 10:56:40]

Fair enough. I added it as as separate config and didn't include it in msan but
only the chromium_msan config. 

+  gyp_defs['instrumented_libraries_jobs'] = 10
+
 @config_ctx(group='memory_tool')
 def memcheck(c):
   _memory_tool(c, 'memcheck')
   c.gyp_env.GYP_DEFINES['build_for_tool'] = 'memcheck'
 
 @config_ctx(deps=['compiler'], group='memory_tool')
 def tsan2(c):
   if 'clang' not in c.compile_py.compiler:  # pragma: no cover
     raise BadConf('tsan2 requires clang')
   gyp_defs = c.gyp_env.GYP_DEFINES
@@ skipping 47 matching lines @@
 def chromium(c):
   c.compile_py.default_targets = ['All', 'chromium_builder_tests']
 
 @config_ctx(includes=['ninja', 'clang', 'goma', 'asan'])
 def chromium_asan(c):
   c.runtests.lsan_suppressions_file = Path('[CHECKOUT]', 'tools', 'lsan',
                                            'suppressions.txt')
   c.runtests.test_args.append('--test-launcher-batch-limit=1')
   c.runtests.test_args.append('--test-launcher-print-test-stdio=always')
 
+@config_ctx(includes=['ninja', 'clang', 'goma', 'msan'])
+def chromium_msan(c):
+  c.compile_py.default_targets = ['All', 'chromium_builder_tests']
+
 @config_ctx(includes=['ninja', 'clang', 'goma', 'syzyasan'])
 def chromium_syzyasan(c):
   c.compile_py.default_targets = ['All', 'chromium_builder_tests']
 
 @config_ctx(includes=['ninja', 'clang', 'goma', 'tsan2'])
 def chromium_tsan2(c):
   c.compile_py.default_targets = ['All', 'chromium_builder_tests']
 
 @config_ctx(includes=['ninja', 'default_compiler', 'goma', 'chromeos'])
 def chromium_chromeos(c):
@@ skipping 121 matching lines @@
   c.gyp_env.GYP_DEFINES['v8_optimized_debug'] = 1
 
 @config_ctx()
 def chromium_perf(c):
   c.compile_py.clobber = False
   if c.HOST_PLATFORM == 'win':
     c.compile_py.compiler = None
     c.compile_py.goma_dir = None
     c.gyp_env.GYP_DEFINES['use_goma'] = 0