Try to simplify the semantics of the profiling code by making...

test/cctest/test-log.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 //
 // Tests of logging functions from log.h
 
 #ifdef ENABLE_LOGGING_AND_PROFILING
 
 #ifdef __linux__
 #include <math.h>
 #include <pthread.h>
 #include <signal.h>
@@ skipping 451 matching lines @@
   sampler.Start();
   CHECK(!sampler.WasSampleStackCalled());
   jsThread.WaitForRunning();
   jsThread.SendSigProf();
   CHECK(sampler.WaitForTick());
   CHECK(sampler.WasSampleStackCalled());
   sampler.Reset();
   CHECK(!sampler.WasSampleStackCalled());
   nonJsThread.WaitForRunning();
   nonJsThread.SendSigProf();
-  CHECK(sampler.WaitForTick());
+  CHECK(!sampler.WaitForTick());
   CHECK(!sampler.WasSampleStackCalled());
   sampler.Stop();
 
   jsThread.Stop();
   nonJsThread.Stop();
   jsThread.Join();
   nonJsThread.Join();
 }
 
 #endif  // __linux__
@@ skipping 706 matching lines @@
   // Make sure that all log data is written prior crash due to CHECK failure.
   fflush(stdout);
   CHECK(results_equal);
 
   env->Exit();
   Logger::TearDown();
   i::FLAG_always_compact = saved_always_compact;
 }
 
 #endif  // ENABLE_LOGGING_AND_PROFILING