Turn on C++11 when building with gcc4.8+

build/config/compiler/BUILD.gn

 # Copyright (c) 2013 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.
 
 import("//build/config/android/config.gni")
 if (cpu_arch == "arm") {
   import("//build/config/arm.gni")
 }
 if (is_posix) {
   import("//build/config/gcc/gcc_version.gni")
@@ skipping 87 matching lines @@
     # an Objective C struct won't be called, which is very bad.
     cflags_objcc = [ "-fobjc-call-cxx-cdtors", ]
 
     cflags_c += [ "-std=c99" ]
     cflags_cc += [ "-std=gnu++11" ]
 
     ldflags += common_mac_flags
   } else if (is_posix) {
     # Non-Mac Posix compiler flags setup.
     # -----------------------------------
+    if (gcc_version >= 48) {
+      cflags_cc += [
+        "-std=gnu++11",
+      ]
+    }
 
     # CPU architecture. We may or may not be doing a cross compile now, so for
     # simplicity we always explicitly set the architecture.
     if (cpu_arch == "x64") {
       cflags += [ "-m64" ]
       ldflags += [ "-m64" ]
     } else if (cpu_arch == "x86") {
       cflags += [ "-m32" ]
       ldflags += [ "-m32" ]
     } else if (cpu_arch == "arm") {
@@ skipping 447 matching lines @@
   } else {
     # Common GCC warning setup.
     cflags = [
       # Enables.
       "-Wendif-labels",  # Weird old-style text after an #endif.
 
       # Disables.
       "-Wno-missing-field-initializers",  # "struct foo f = {0};"
       "-Wno-unused-parameter",  # Unused function parameters.
     ]
+    cflags_cc = []
 
     if (is_mac) {
       cflags += [
         "-Wnewline-eof",
       ]
     }
 
     if (is_clang) {
       cflags += [
         # This warns on using ints as initializers for floats in
@@ skipping 12 matching lines @@
         "-Wno-covered-switch-default",
 
         # Clang considers the `register` keyword as deprecated, but e.g.
         # code generated by flex (used in angle) contains that keyword.
         # http://crbug.com/255186
         "-Wno-deprecated-register",
 
         # Clang spots more unused functions.
         "-Wno-unused-function",
       ]
+
+      if (!is_mac && !is_ios) {
+        cflags_cc += [
+          "-Wno-reserved-user-defined-literal",
+        ]
+      }
+    }
+    if (gcc_version >= 48) {
+      cflags_cc += [
+        # See comment for -Wno-c++11-narrowing.
+        "-Wno-narrowing",
+        # TODO(thakis): Remove, http://crbug.com/263960
+        "-Wno-literal-suffix",
+      ]
     }
 
     # Suppress warnings about ABI changes on ARM (Clang doesn't give this
     # warning).
     if (cpu_arch == "arm" && !is_clang) {
       cflags += [ "-Wno-psabi" ]
     }
 
     if (is_android) {
       # Disable any additional warnings enabled by the Android build system but
       # which chromium does not build cleanly with (when treating warning as
       # errors).
       cflags += [
         "-Wno-extra",
         "-Wno-ignored-qualifiers",
         "-Wno-type-limits",
       ]
-      cflags_cc = [
+      cflags_cc += [
         # Disabling c++0x-compat should be handled in WebKit, but
         # this currently doesn't work because gcc_version is not set
         # correctly when building with the Android build system.
         # TODO(torne): Fix this in WebKit.
         "-Wno-error=c++0x-compat",
         # Other things unrelated to -Wextra:
         "-Wno-non-virtual-dtor",
         "-Wno-sign-promo",
       ]
     }
@@ skipping 162 matching lines @@
   } else {
     cflags = [ "-g1" ]
   }
 }
 
 config("no_symbols") {
   if (!is_win) {
     cflags = [ "-g0" ]
   }
 }