Switch to vectors instead of bare char* arrays.

src/conversions.cc

 // Copyright 2006-2008 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 751 matching lines @@
     case FP_ZERO:
       builder.AddCharacter('0');
       break;
 
     default: {
       int decimal_point;
       int sign;
 
       char* decimal_rep;
       bool used_gay_dtoa = false;
-      char fast_dtoa_buffer[kFastDtoaMaximalLength + 1];
+      const int kFastDtoaBufferCapacity = kFastDtoaMaximalLength + 1;
+      char fast_dtoa_buffer[kFastDtoaBufferCapacity];
       int length;
-      if (FastDtoa(v, fast_dtoa_buffer, &sign, &length, &decimal_point)) {
+      if (FastDtoa(v, Vector<char>(fast_dtoa_buffer, kFastDtoaBufferCapacity),
+                   &sign, &length, &decimal_point)) {
         decimal_rep = fast_dtoa_buffer;
       } else {
         decimal_rep = dtoa(v, 0, 0, &decimal_point, &sign, NULL);
         used_gay_dtoa = true;
         length = StrLength(decimal_rep);
       }
 
       if (sign) builder.AddCharacter('-');
 
       if (length <= decimal_point && decimal_point <= 21) {
@@ skipping 309 matching lines @@
   // Allocate result and fill in the parts.
   StringBuilder builder(result_size + 1);
   builder.AddSubstring(integer_buffer + integer_pos + 1, integer_part_size);
   if (decimal_pos > 0) builder.AddCharacter('.');
   builder.AddSubstring(decimal_buffer, decimal_pos);
   return builder.Finalize();
 }
 
 
 } }  // namespace v8::internal