Adding GYP_DEFINES=ASAN to enable ASAN build

build/common.gypi

 # Copyright (c) 2011 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 163 matching lines @@
 
       # Safe browsing is compiled in by default. Set to 0 to disable.
       'safe_browsing%': 1,
 
       # If this is set, the clang plugins used on the buildbot will be used.
       # Run tools/clang/scripts/update.sh to make sure they are compiled.
       # This causes 'clang_chrome_plugins_flags' to be set.
       # Has no effect if 'clang' is not set as well.
       'clang_use_chrome_plugins%': 0,
 
+      # Enable building with ASAN (Clang's -fasan option).
+      # -fasan only works with clang, but asan=1 implies clang=1
+      # See https://sites.google.com/a/chromium.org/dev/developers/testing/addresssanitizer
+      'asan%': 0,
+
       # Set to 1 compile with -fPIC cflag on linux. This is a must for shared
       # libraries on linux x86-64 and arm, plus ASLR.
       'linux_fpic%': 1,
 
       # Enable navigator.registerProtocolHandler and supporting UI.
       'enable_register_protocol_handler%': 1,
 
       # Enable Web Intents and supporting UI.
       'enable_web_intents%': 0,
 
@@ skipping 105 matching lines @@
     'disable_sse2%': '<(disable_sse2)',
     'component%': '<(component)',
     'use_titlecase_in_grd_files%': '<(use_titlecase_in_grd_files)',
     'use_third_party_translations%': '<(use_third_party_translations)',
     'remoting%': '<(remoting)',
     'enable_webrtc%': '<(enable_webrtc)',
     'p2p_apis%': '<(p2p_apis)',
     'configuration_policy%': '<(configuration_policy)',
     'safe_browsing%': '<(safe_browsing)',
     'clang_use_chrome_plugins%': '<(clang_use_chrome_plugins)',
+    'asan%': '<(asan)',
     'enable_register_protocol_handler%': '<(enable_register_protocol_handler)',
     'enable_smooth_scrolling%': '<(enable_smooth_scrolling)',
     # Whether to build for Wayland display server
     'use_wayland%': 0,
 
     # The release channel that this build targets. This is used to restrict
     # channel-specific build options, like which installer packages to create.
     # The default is 'all', which does no channel-specific filtering.
     'channel%': 'all',
 
@@ skipping 364 matching lines @@
       # Set use_ibus to 1 to enable ibus support.
       ['touchui==1 and chromeos==1', {
         'use_ibus%': 1,
       }, {
         'use_ibus%': 0,
       }],
 
       ['enable_register_protocol_handler==1', {
         'grit_defines': ['-D', 'enable_register_protocol_handler'],
       }],
+
+      ['asan==1', {
+        'clang%': 1,
+      }],
     ],
   },
   'target_defaults': {
     'variables': {
       # The condition that operates on chromium_code is in a target_conditions
       # section, and will not have access to the default fallback value of
       # chromium_code at the top of this file, or to the chromium_code
       # variable placed at the root variables scope of .gyp files, because
       # those variables are not set at target scope.  As a workaround,
       # if chromium_code is not set at target scope, define it in target scope
@@ skipping 833 matching lines @@
             'cflags': [
               '<(clang_chrome_plugins_flags)',
             ],
           }],
           ['clang==1 and clang_load!="" and clang_add_plugin!=""', {
             'cflags': [
               '-Xclang', '-load', '-Xclang', '<(clang_load)',
               '-Xclang', '-add-plugin', '-Xclang', '<(clang_add_plugin)',
             ],
           }],
+          ['asan==1', {
+            # Only in the linux section for now, since ASAN doesn't
+            # work on Mac yet.
+            'cflags': [
+              '-fasan -w',
+            ],
+            'ldflags': [
+              '-fasan',
+            ],
+          }],
           ['no_strict_aliasing==1', {
             'cflags': [
               '-fno-strict-aliasing',
             ],
           }],
           ['linux_breakpad==1', {
             'cflags': [ '-g' ],
             'defines': ['USE_LINUX_BREAKPAD'],
           }],
           ['linux_use_heapchecker==1', {
@@ skipping 402 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }