Fix compilation with clang

src/assembler.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 288 matching lines @@
 //        or
 //          pc-jump (variable length):
 //                               01 1111 11,
 //                               [7 bits data] 0
 //                                  ...
 //                               [7 bits data] 1
 //               (Bits 6..31 of pc delta, with leading zeroes
 //                dropped, and last non-zero chunk tagged with 1.)
 
 
+#ifdef DEBUG
 const int kMaxStandardNonCompactModes = 14;
+#endif
 
 const int kTagBits = 2;
 const int kTagMask = (1 << kTagBits) - 1;
 const int kExtraTagBits = 4;
 const int kLocatableTypeTagBits = 2;
 const int kSmallDataBits = kBitsPerByte - kLocatableTypeTagBits;
 
 const int kEmbeddedObjectTag = 0;
 const int kCodeTargetTag = 1;
 const int kLocatableTag = 2;
@@ skipping 1337 matching lines @@
     assembler_->RecordRelocInfo(RelocInfo::POSITION, state_.current_position);
     state_.written_position = state_.current_position;
     written = true;
   }
 
   // Return whether something was written.
   return written;
 }
 
 } }  // namespace v8::internal