| Index: src/incremental-marking.cc | 
| diff --git a/src/incremental-marking.cc b/src/incremental-marking.cc | 
| index 32a084dc2d79f5dc89c2ac3d0a3e5f7bbd8ade04..ba973c9406b841c6f562c92e666e07ce18ac128e 100644 | 
| --- a/src/incremental-marking.cc | 
| +++ b/src/incremental-marking.cc | 
| @@ -561,8 +561,8 @@ void IncrementalMarking::StartMarking(CompactionFlag flag) { | 
|  | 
| ActivateIncrementalWriteBarrier(); | 
|  | 
| -#ifdef DEBUG | 
| // Marking bits are cleared by the sweeper. | 
| +#ifdef VERIFY_HEAP | 
| if (FLAG_verify_heap) { | 
| heap_->mark_compact_collector()->VerifyMarkbitsAreClean(); | 
| } | 
|  |