mac: Build in C++11 mode.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 9e90c3a14b7d67421a4d446eb4aa2f4b854af983..c9c8c5bd191a4eb7a32f7f738f63e729c511ae0c 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -3247,21 +3247,37 @@
               'GCC_VERSION': 'com.apple.compilers.llvm.clang.1_0',
               'WARNING_CFLAGS': [
                 '-Wheader-hygiene',
+                # This warns on using ints as initializers for floats in

[Mark Mentovai, 2012/12/04 03:52:08]

I find these comments easier to read and it makes the compiler arguments they’re
attached to more obvious if there’s some vertical whitespace. So, blank line
before this line, and also before 3255.

+                # 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',
+
                 # 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',
-                # See comments on this flag higher up in this file.
-                '-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',
               ],
+              'OTHER_CPLUSPLUSFLAGS': [
+                # gnu++11 instead of c++11 so that __ANSI_C__ doesn't get
+                # defined.  (Else e.g. finite() in base/float_util.h needs to
+                # be isfinite() which doesn't exist on the android bots.)
+                # typeof() is also disabled in c++11 (but we could use
+                # decltype() instead).

[Mark Mentovai, 2012/12/04 03:52:08]

Ultimately, I’d rather these couple of things and use -std=c++11.

+                # TODO(thakis): Use CLANG_CXX_LANGUAGE_STANDARD instead once all
+                # bots use xcode 4 -- http://crbug.com/147515).
+                '$(inherited)', '-std=gnu++11',
+              ],
             }],
             ['clang==1 and clang_use_chrome_plugins==1', {
               'OTHER_CFLAGS': [