Support vtable_verify (new compiler option).

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 369 matching lines @@
       # It must not be '<(PRODUCT_DIR)' alone, the '/' is necessary otherwise
       # gyp will remove duplicate flags, causing isolate.py to be confused.
       'test_isolation_outdir%': '<(PRODUCT_DIR)/isolate',
 
        # Force rlz to use chrome's networking stack.
       'force_rlz_use_chrome_net%': 1,
 
       'sas_dll_path%': '<(DEPTH)/third_party/platformsdk_win7/files/redist/x86',
       'wix_path%': '<(DEPTH)/third_party/wix',
 
+      # Whether or not to turn on vtable verification hardening.

[Mark Mentovai, 2012/08/13 20:07:12]

Do you need this? Can you get rid of it and move the comment and default 0 value
down to the enclosing scope?

+      'use_vtable_verify%': 0,
+
+
       'conditions': [
         # TODO(epoger): Figure out how to set use_skia=1 for Mac outside of
         # the 'conditions' clause.  Initial attempts resulted in chromium and
         # webkit disagreeing on its setting.
         ['OS=="mac"', {
           'use_skia%': 1,
         }, {
           'use_skia%': 1,
         }],
 
@@ skipping 208 matching lines @@
     'enable_automation%': '<(enable_automation)',
     'enable_printing%': '<(enable_printing)',
     'enable_captive_portal_detection%': '<(enable_captive_portal_detection)',
     'force_rlz_use_chrome_net%': '<(force_rlz_use_chrome_net)',
     'enable_task_manager%': '<(enable_task_manager)',
     'sas_dll_path%': '<(sas_dll_path)',
     'wix_path%': '<(wix_path)',
     'android_upstream_bringup%': '<(android_upstream_bringup)',
     'use_system_libjpeg%': '<(use_system_libjpeg)',
     'android_build_type%': '<(android_build_type)',
+    'use_vtable_verify%': '<(use_vtable_verify)',
 
     # Use system yasm instead of bundled one.
     'use_system_yasm%': 0,
 
     # Default to enabled PIE; this is important for ASLR but we may need to be
     # able to turn it off for various reasons.
     'linux_disable_pie%': 0,
 
     # The release channel that this build targets. This is used to restrict
     # channel-specific build options, like which installer packages to create.
@@ skipping 584 matching lines @@
         'win_release_InlineFunctionExpansion': '0',
         'win_release_OmitFramePointers': '0',
 
         'linux_use_tcmalloc': 1,
         'release_valgrind_build': 1,
         'werror': '',
         'component': 'static_library',
         'use_system_zlib': 0,
       }],
 
+      ['use_vtable_verify==1', {
+       'debug_extra_cflags': '-fvtable-verify=std',

[Mark Mentovai, 2012/08/13 20:07:12]

Fix up weird indentation here too.

+       'release_extra_cflags': '-fvtable-verify=std',
+       }],
+
       # Build tweaks for DrMemory.
       # TODO(rnk): Combine with tsan config to share the builder.
       # http://crbug.com/108155
       ['build_for_tool=="drmemory"', {
         # DrMemory can't handle the debug CRT dll, so build static.
         'component': 'static_library',
         # These runtime checks force initialization of stack vars which blocks
         # DrMemory's uninit detection.
         'win_debug_RuntimeChecks': '0',
         # Iterator debugging is slow.
@@ skipping 2114 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',
   },
 }