It is not necessary to disable Visual C++ warning C4334 when

nss.gyp

 # 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.
 
 {
   'variables': {
     'conditions': [
       ['OS=="ios"', {
         'exclude_nss_root_certs%': 0,
         'exclude_nss_libpkix%': 0,
@@ skipping 223 matching lines @@
         'defines': [
           'NO_NSPR_10_SUPPORT',
         ],
         'include_dirs': [
           'mozilla/nsprpub/pr/include',
           'mozilla/nsprpub/lib/ds',
           'mozilla/nsprpub/lib/libc/include',
         ],
       },
       # TODO(wtc): suppress C4244 and C4554 in prdtoa.c.
-      'msvs_disabled_warnings': [4018, 4244, 4554, 4267, 4334,],
+      'msvs_disabled_warnings': [4018, 4244, 4554, 4267,],
       'conditions': [
         ['OS=="mac" or OS=="ios"', {
           'defines': [
             'XP_UNIX',
             'DARWIN',
             'XP_MACOSX',
             '_PR_PTHREADS',
             'HAVE_BSD_FLOCK',
             'HAVE_CRT_EXTERNS_H',
             'HAVE_DLADDR',
@@ skipping 902 matching lines @@
             '-Wno-incompatible-pointer-types',
             '-Wno-logical-op-parentheses',
             '-Wno-switch',
             '-Wno-tautological-compare',
           ],
         }],
       ],
     },
   ],
 }