Use lazy instance initializer to remove static initializers in two places.

src/platform-posix.cc

 // Copyright 2011 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 109 matching lines @@
 
 
 // ----------------------------------------------------------------------------
 // Math functions
 
 double modulo(double x, double y) {
   return fmod(x, y);
 }
 
 
-static Mutex* math_function_mutex = OS::CreateMutex();
+static LazyMutex math_function_mutex = LAZY_MUTEX_INITIALIZER;
 
 #define UNARY_MATH_FUNCTION(name, generator)             \
 static UnaryMathFunction fast_##name##_function = NULL;  \
 double fast_##name(double x) {                           \
   if (fast_##name##_function == NULL) {                  \
-    ScopedLock lock(math_function_mutex);                \
+    ScopedLock lock(math_function_mutex.Pointer());      \
     UnaryMathFunction temp = generator;                  \
     MemoryBarrier();                                     \
     fast_##name##_function = temp;                       \
   }                                                      \
   return (*fast_##name##_function)(x);                   \
 }
 
 UNARY_MATH_FUNCTION(sin, CreateTranscendentalFunction(TranscendentalCache::SIN))
 UNARY_MATH_FUNCTION(cos, CreateTranscendentalFunction(TranscendentalCache::COS))
 UNARY_MATH_FUNCTION(tan, CreateTranscendentalFunction(TranscendentalCache::TAN))
@@ skipping 368 matching lines @@
   return ntohl(value);
 }
 
 
 Socket* OS::CreateSocket() {
   return new POSIXSocket();
 }
 
 
 } }  // namespace v8::internal