clang: Build in C++11 mode on linux & cros too.

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 2985 matching lines @@
                 ],
                 'ldflags': [
                   '--sysroot=<(sysroot)',
                   '<!(<(DEPTH)/build/linux/sysroot_ld_path.sh <(sysroot))',
                 ],
               }]]
           }],
           ['clang==1', {
             'cflags': [
               '-Wheader-hygiene',
+
+              # Don't die on dtoa code that uses a char as an array index.
+              '-Wno-char-subscripts',
+
               # Clang spots more unused functions.
               '-Wno-unused-function',
-              # Don't die on dtoa code that uses a char as an array index.
-              '-Wno-char-subscripts',
-              # Especially needed for gtest macros using enum values from Mac
-              # system headers.
-              # TODO(pkasting): In C++11 this is legal, so this should be
-              # removed when we change to that.  (This is also why we don't
-              # bother fixing all these cases today.)
-              '-Wno-unnamed-type-template-args',
-              # This (rightfully) complains about 'override', which we use
-              # heavily.
-              '-Wno-c++11-extensions',
 
               # Warns on switches on enums that cover all enum values but
               # also contain a default: branch. Chrome is full of that.
               '-Wno-covered-switch-default',
 
               # Warns when a const char[] is converted to bool.
               '-Wstring-conversion',
             ],
             'cflags!': [
               # Clang doesn't seem to know know this flag.
               '-mfpmath=sse',
             ],
           }],
+          ['clang==1 and (OS!="android" and chromeos!=1)', {
+            # Turn on C++11.
+            'cflags': [
+              # This warns on using ints as initializers for floats in
+              # initializer lists (e.g. |int a = f(); CGSize s = { a, a };|),
+              # which happens in several places in chrome code. Not sure if
+              # this is worth fixing.
+              '-Wno-c++11-narrowing',
+
+              # This warns about code like |"0x%08"NACL_PRIxPTR| -- with C++11
+              # user-defined literals, this is now a string literal with a UD
+              # suffix. However, this is used heavily in NaCl code, so disable
+              # the warning for now.
+              '-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.
+              '-std=gnu++11',

[tfarina, 2013/05/01 23:44:55]

looks like this broke my build, and the instructions were not updated?
https://code.google.com/p/chromium/wiki/LinuxBuildInstructions

+            ],
+          }],
+          ['clang==1 and (OS=="android" or chromeos==1)', {
+            # Android uses gcc4.4, and clang isn't compatible with gcc4.4's
+            # libstdc++ in C++11 mode. So no C++11 mode for Android yet.
+            # Doesn't work with asan for some reason either: crbug.com/233464
+            'cflags': [
+              # Especially needed for gtest macros using enum values from Mac   
+              # system headers. 
+              # TODO(pkasting): In C++11 this is legal, so this should be       
+              # removed when we change to that.  (This is also why we don't     
+              # bother fixing all these cases today.)   
+              '-Wno-unnamed-type-template-args',        
+              # This (rightfully) complains about 'override', which we use      
+              # heavily.        
+              '-Wno-c++11-extensions',
+            ],
+          }],
           ['clang==1 and clang_use_chrome_plugins==1', {
             'cflags': [
               '<@(clang_chrome_plugins_flags)',
             ],
           }],
           ['clang==1 and clang_load!=""', {
             'cflags': [
               '-Xclang', '-load', '-Xclang', '<(clang_load)',
             ],
           }],
@@ skipping 616 matching lines @@
 
                 # This warns about code like |"0x%08"NACL_PRIxPTR| -- with C++11
                 # user-defined literals, this is now a string literal with a UD
                 # suffix. However, this is used heavily in NaCl code, so disable
                 # the warning for now.
                 '-Wno-reserved-user-defined-literal',
 
                 # Don't die on dtoa code that uses a char as an array index.
                 # This is required solely for base/third_party/dmg_fp/dtoa.cc.
                 '-Wno-char-subscripts',
+
                 # Clang spots more unused functions.
                 '-Wno-unused-function',
 
                 # Warns on switches on enums that cover all enum values but
                 # also contain a default: branch. Chrome is full of that.
                 '-Wno-covered-switch-default',
 
                 # Warns when a const char[] is converted to bool.
                 '-Wstring-conversion',
               ],
@@ skipping 691 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',
   },
 }