--- a/security/certverifier/moz.build
+++ b/security/certverifier/moz.build
@@ -38,16 +38,17 @@ if CONFIG['_MSC_VER']:
     '-wd4514', # 'function': unreferenced inline function has been removed
     '-wd4610', # struct 'symbol' can never be instantiated - user defined
                # constructor required
     '-wd4619', # pragma warning: there is no warning 'warning'
     '-wd4625', # copy constructor could not be generated because a base
                # class copy constructor is inaccessible or deleted
     '-wd4626', # assignment operator could not be generated because a base
                # class assignment operator is inaccessible or deleted
+    '-wd4640', # construction of local static object is not thread-safe
     '-wd4710', # 'function': function not inlined
     '-wd4711', # function 'function' selected for inline expansion
     '-wd4820', # 'bytes' bytes padding added after construct 'member_name'
   ]
 
   # MSVC 2010's headers trigger these
   CXXFLAGS += [
       '-wd4548', # expression before comma has no effect; ...