Use PrintF instead of fprintf.

src/objects.cc

 // Copyright 2013 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 7973 matching lines @@
   Heap* heap = GetHeap();
   if (start == 0 && end == length()) return this;
   MaybeObject* result = heap->AllocateSubString(this, start, end, pretenure);
   return result;
 }
 
 
 void String::PrintOn(FILE* file) {
   int length = this->length();
   for (int i = 0; i < length; i++) {
-    fprintf(file, "%c", Get(i));
+    PrintF(file, "%c", Get(i));
   }
 }
 
 
 static void TrimEnumCache(Heap* heap, Map* map, DescriptorArray* descriptors) {
   int live_enum = map->EnumLength();
   if (live_enum == Map::kInvalidEnumCache) {
     live_enum = map->NumberOfDescribedProperties(OWN_DESCRIPTORS, DONT_ENUM);
   }
   if (live_enum == 0) return descriptors->ClearEnumCache();
@@ skipping 6460 matching lines @@
   set_year(Smi::FromInt(year), SKIP_WRITE_BARRIER);
   set_month(Smi::FromInt(month), SKIP_WRITE_BARRIER);
   set_day(Smi::FromInt(day), SKIP_WRITE_BARRIER);
   set_weekday(Smi::FromInt(weekday), SKIP_WRITE_BARRIER);
   set_hour(Smi::FromInt(hour), SKIP_WRITE_BARRIER);
   set_min(Smi::FromInt(min), SKIP_WRITE_BARRIER);
   set_sec(Smi::FromInt(sec), SKIP_WRITE_BARRIER);
 }
 
 } }  // namespace v8::internal