A64: Fix ArrayConstructorStub and remove GCC 4.8 specific flags.

build/toolchain.gypi

 # Copyright 2013 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 502 matching lines @@
               }],
             ],
           },
         },
         'conditions': [
           ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="netbsd" or \
             OS=="qnx"', {
             'cflags': [ '-Wall', '<(werror)', '-W', '-Wno-unused-parameter',
                         '-Wnon-virtual-dtor', '-Woverloaded-virtual',
                         '<(wno_array_bounds)',
-                        # Hide some GCC 4.8 warnings:
-                        # TODO(jbramley): Only enable these on GCC 4.8.
-                        '-Wno-unused-local-typedefs',
-                        '-Wno-maybe-uninitialized' ],
+                      ],
             'conditions': [
               ['v8_optimized_debug==0', {
                 'cflags!': [
                   '-O0',
                   '-O3',
                   '-O2',
                   '-O1',
                   '-Os',
                 ],
                 'cflags': [
@@ skipping 81 matching lines @@
       'Release': {
         'conditions': [
           ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="netbsd"', {
             'cflags!': [
               '-Os',
             ],
             'cflags': [
               '-fdata-sections',
               '-ffunction-sections',
               '<(wno_array_bounds)',
-              # Hide some GCC 4.8 warnings:
-              # TODO(jbramley): Only enable these on GCC 4.8.
-              '-Wno-unused-local-typedefs',
-              '-Wno-maybe-uninitialized',
             ],
             'conditions': [
               [ 'gcc_version==44 and clang==0', {
                 'cflags': [
                   # Avoid crashes with gcc 4.4 in the v8 test suite.
                   '-fno-tree-vrp',
                 ],
               }],
               # TODO(crbug.com/272548): Avoid -O3 in NaCl
               ['nacl_target_arch=="none"', {
@@ skipping 60 matching lines @@
                 'OptimizeReferences': '2',
                 'EnableCOMDATFolding': '2',
               },
             },
           }],  # OS=="win"
         ],  # conditions
       },  # Release
     },  # configurations
   },  # target_defaults
 }