Add safe handling of NaN to Posix platform-dependent time functions.

src/platform-posix.cc

 // Copyright 2009 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 69 matching lines @@
 int64_t OS::Ticks() {
   // gettimeofday has microsecond resolution.
   struct timeval tv;
   if (gettimeofday(&tv, NULL) < 0)
     return 0;
   return (static_cast<int64_t>(tv.tv_sec) * 1000000) + tv.tv_usec;
 }
 
 
 const char* OS::LocalTimezone(double time) {
-  ASSERT(!isnan(time));
+  if (isnan(time)) return "";
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));
   struct tm* t = localtime(&tv);
   if (NULL == t) return "";
   return t->tm_zone;
 }
 
 
 double OS::DaylightSavingsOffset(double time) {
-  ASSERT(!isnan(time));
+  if (isnan(time)) return nan_value();
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));
   struct tm* t = localtime(&tv);
   if (NULL == t) return nan_value();
   return t->tm_isdst > 0 ? 3600 * msPerSecond : 0;
 }
 
 
 double OS::LocalTimeOffset() {
   time_t tv = time(NULL);
   struct tm* t = localtime(&tv);
@@ skipping 248 matching lines @@
   return ntohl(value);
 }
 
 
 Socket* OS::CreateSocket() {
   return new POSIXSocket();
 }
 
 
 } }  // namespace v8::internal