- Initialize BG(serialize_lock) to make valgrind happy

ext/standard/basic_functions.c

@@ -3452,6 +3452,7 @@ static void basic_globals_ctor(php_basic_globals *basic_globals_p TSRMLS_DC) /*
 	BG(left) = -1;
 	BG(user_tick_functions) = NULL;
 	BG(user_filter_map) = NULL;
+	BG(serialize_lock) = 0;
 	
 	memset(&BG(serialize), 0, sizeof(BG(serialize)));
 	memset(&BG(unserialize), 0, sizeof(BG(unserialize)));