mac: use -std=c++11 instead of -std=gnu++11.

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 4060 matching lines @@
                   '<!(<(DEPTH)/build/linux/sysroot_ld_path.sh <(sysroot))',
                 ],
               }]]
           }],
           ['clang==1', {
             'cflags': [
               # TODO(thakis): Remove, http://crbug.com/263960
               '-Wno-reserved-user-defined-literal',
             ],
             'cflags_cc': [
-              # See the comment in the Mac section for what it takes to move
-              # this to -std=c++11.
+              # gnu++11 instead of c++11 is needed because some code uses
+              # typeof() (a GNU extension).
+              # TODO(thakis): Eventually switch this to c++11 instead,
+              # http://crbug.com/427584
               '-std=gnu++11',
             ],
           }],
           ['clang==0 and host_clang==1', {
             'target_conditions': [
               ['_toolset=="host"', {
                 'cflags_cc': [ '-std=gnu++11', ],
               }],
             ],
           }],
@@ skipping 734 matching lines @@
             # pattern.
             '-Wno-missing-field-initializers',
           ],
           'conditions': [
             ['chromium_mac_pch', {'GCC_PRECOMPILE_PREFIX_HEADER': 'YES'},
                                  {'GCC_PRECOMPILE_PREFIX_HEADER': 'NO'}
             ],
             # Note that the prebuilt Clang binaries should not be used for iOS
             # development except for ASan builds.
             ['clang==1', {
-              # gnu++11 instead of c++11 is needed because some code uses
-              # typeof() (a GNU extension).
-              # TODO(thakis): Eventually switch this to c++11 instead of
-              # gnu++11 (once typeof can be removed, which is blocked on c++11
-              # being available everywhere).
-              'CLANG_CXX_LANGUAGE_STANDARD': 'gnu++11',  # -std=gnu++11
+              'CLANG_CXX_LANGUAGE_STANDARD': 'c++11',  # -std=c++11
               # Warn if automatic synthesis is triggered with
               # the -Wobjc-missing-property-synthesis flag.
               'CLANG_WARN_OBJC_MISSING_PROPERTY_SYNTHESIS': 'YES',
               'GCC_VERSION': 'com.apple.compilers.llvm.clang.1_0',
               'WARNING_CFLAGS': [
                 # This warns on selectors from Cocoa headers (-length, -set).
                 # cfe-dev is currently discussing the merits of this warning.
                 # TODO(thakis): Reevaluate what to do with this, based one
                 # cfe-dev discussion.
                 '-Wno-selector-type-mismatch',
@@ skipping 1026 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',
   },
 }