Always define the `gcc_version' variable to some value.

chrome/chrome_browser.gypi

 # Copyright 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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 2853 matching lines @@
               ],
             }],
             # GTK build only
             ['toolkit_uses_gtk==1', {
               'sources/': [
                 ['exclude', '^browser/lifetime/application_lifetime_stub.cc'],
                 ['include', '^browser/printing/print_dialog_gtk.cc'],
                 ['include', '^browser/printing/print_dialog_gtk.h'],
               ],
             }],
-            ['os_posix == 1 and OS != "mac" and OS != "ios" and OS != "android" and gcc_version == 45', {
+            ['gcc_version == 45', {
               # Avoid gcc 4.5 miscompilation of template_url.cc
               # as per http://crbug.com/41887
               'cflags': [
                 '-fno-ipa-cp',
               ],
             }],
           ],
         }],
         ['enable_plugin_installation==0', {
           'sources!': [
@@ skipping 206 matching lines @@
             'package_name': 'org/chromium/chrome/browser/ui/toolbar',
             'template_deps': ['browser/ui/toolbar/toolbar_model_security_level_list.h'],
           },
           'includes': [ '../build/android/java_cpp_template.gypi' ],
         },
       ],
      },
     ],
   ],
 }