DebugBreak shouldn't be used when ENABLE_DEBUGGER_SUPPORT isn't defined.

src/codegen.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 476 matching lines @@
     *code_out = Code::cast(cache);
     return true;
   }
 }
 
 
 void ApiGetterEntryStub::SetCustomCache(Code* value) {
   info()->set_load_stub_cache(value);
 }
 
-
+#ifdef ENABLE_DEBUGGER_SUPPORT
 void DebugerStatementStub::Generate(MacroAssembler* masm) {
   Runtime::Function* f = Runtime::FunctionForId(Runtime::kDebugBreak);
   masm->TailCallRuntime(ExternalReference(f), 0, f->result_size);
 }
+#endif
 
 
 } }  // namespace v8::internal