Implement use_cfi_cast to optionally enable cast checks.

build/common.gypi

 # Copyright (c) 2012 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 680 matching lines @@
 
       # Libxkbcommon usage.
       'use_xkbcommon%': 0,
 
       # Whether we use GTKv3 on linux.
       'use_gtk3%': 0,
 
       # Control Flow Integrity for virtual calls and casts.
       # See http://clang.llvm.org/docs/ControlFlowIntegrity.html
       'cfi_vptr%': 0,
+      # TODO(krasin): remove it. See https://crbug.com/626794.
+      'cfi_cast%': 0,
       'cfi_diag%': 0,
 
       'cfi_blacklist%': '<(PRODUCT_DIR)/../../tools/cfi/blacklist.txt',
 
       # Whether the entire browser uses toolkit-views on Mac instead of Cocoa.
       'mac_views_browser%': 0,
 
       # By default, use ICU data file (icudtl.dat).
       'icu_use_data_file_flag%': 1,
 
@@ skipping 541 matching lines @@
     'enable_hangout_services_extension%' : '<(enable_hangout_services_extension)',
     'proprietary_codecs%': '<(proprietary_codecs)',
     'use_goma%': '<(use_goma)',
     'gomadir%': '<(gomadir)',
     'use_lto%': '<(use_lto)',
     'use_lto_o2%': '<(use_lto_o2)',
     'gold_icf_level%': '<(gold_icf_level)',
     'video_hole%': '<(video_hole)',
     'v8_use_external_startup_data%': '<(v8_use_external_startup_data)',
     'cfi_vptr%': '<(cfi_vptr)',
+    'cfi_cast%': '<(cfi_cast)',
     'cfi_diag%': '<(cfi_diag)',
     'cfi_blacklist%': '<(cfi_blacklist)',
     'mac_views_browser%': '<(mac_views_browser)',
     'android_app_version_name%': '<(android_app_version_name)',
     'android_app_version_code%': '<(android_app_version_code)',
     'use_webview_internal_framework%': '<(use_webview_internal_framework)',
     'enable_webvr%': '<(enable_webvr)',
 
     # Turns on compiler optimizations in V8 in Debug build.
     'v8_optimized_debug%': 1,
@@ skipping 4933 matching lines @@
           }],
         ],
       },
     }],
     ['cfi_vptr==1', {
       'target_defaults': {
         'target_conditions': [
           ['_toolset=="target"', {
             'cflags': [
               '-fsanitize=cfi-vcall',
-              '-fsanitize=cfi-derived-cast',
-              '-fsanitize=cfi-unrelated-cast',
               '-fsanitize-blacklist=<(cfi_blacklist)',
             ],
             'ldflags': [
               '-fsanitize=cfi-vcall',
               '-fsanitize=cfi-derived-cast',
               '-fsanitize=cfi-unrelated-cast',
             ],
             'xcode_settings': {
               'OTHER_CFLAGS': [
                 '-fsanitize=cfi-vcall',
-                '-fsanitize=cfi-derived-cast',
-                '-fsanitize=cfi-unrelated-cast',
                 '-fsanitize-blacklist=<(cfi_blacklist)',
               ],
             },
           }],
           ['_toolset=="target" and _type!="static_library"', {
             'xcode_settings':  {
               'OTHER_LDFLAGS': [
                 '-fsanitize=cfi-vcall',
+              ],
+            },
+          }],
+        ],
+      },
+    }],
+    ['cfi_vptr==1 and cfi_cast==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'cflags': [
+              '-fsanitize=cfi-derived-cast',
+              '-fsanitize=cfi-unrelated-cast',
+            ],
+            'ldflags': [
+              '-fsanitize=cfi-derived-cast',
+              '-fsanitize=cfi-unrelated-cast',
+            ],
+            'xcode_settings': {
+              'OTHER_CFLAGS': [
                 '-fsanitize=cfi-derived-cast',
                 '-fsanitize=cfi-unrelated-cast',
               ],
+            },
+          }],
+          ['_toolset=="target" and _type!="static_library"', {
+            'xcode_settings':  {
+              'OTHER_LDFLAGS': [
+                '-fsanitize=cfi-derived-cast',
+                '-fsanitize=cfi-unrelated-cast',
+              ],
             },
           }],
         ],
       },
     }],
     ['cfi_vptr==1 and OS=="win"', {
       'target_defaults': {
         'target_conditions': [
           ['_toolset=="target"', {
             'msvs_settings': {
@@ skipping 66 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',
   },
 }