Unreal, why doesn't the compiler compile the following several lines of code?

Development Programming & Scripting C++
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1

void ACineActor::PrintPlayingAudioName()
{
ALevelSequenceActor* SequenceActor = GetOwningLevelSequenceActor();
ULevelSequencePlayer* SequencePlayer = SequenceActor->SequencePlayer;
if (SequencePlayer == nullptr || !SequencePlayer->IsPlaying())
{
UE_LOG(CineLog, Error, TEXT(“SequencePlayer is null.”));
return;
}

    TSharedRef<FMovieSceneSequenceInstance> movieSceneInstance = ((IMovieScenePlayer*)SequencePlayer)->GetRootMovieSceneSequenceInstance();
    TSharedPtr<FMovieSceneSequenceInstance> movieSceneInstancePtr = movieSceneInstance;
    UE_LOG(CineLog, Error, TEXT("asdf: %s"), *(movieSceneInstance->GetSequence()->GetName()));

    /************************ Here's the problem! *************************/
    // It seems that compiler hasnot compiled the following lines...
    void* pv = &movieSceneInstancePtr;
    unsigned char * pc = (unsigned char *)pv;
    FMovieSceneSequenceInstance* MovieSceneSequenceInstance_tmpPtr = (reinterpret_cast<FMovieSceneSequenceInstance*>(pc));

    TMap<FGuid, FMovieSceneObjectBindingInstanceMock>* ObjectBindingInstances = (TMap<FGuid, FMovieSceneObjectBindingInstanceMock>*) (MovieSceneSequenceInstance_tmpPtr + 78);
    UE_LOG(CineLog, Error, TEXT("alart: %d"), ObjectBindingInstances->GetAllocatedSize())
}

When I debugged the game, I found the debugging yellow arrow just jumped over these lines, and then the engine crashed. Why?

2

The compiler will never leave lines of code “uncompiled”, without an error message. It is likely that some lines have been optimezed out by the compiler. You can avoid this by using the Debug* Configurations instead of the Development* ones.
What does the debugger say when the crash occurs?

3

Void pointer, reinterpret_cast, manual pointer arithmetic - this has crash written all over it.

What are you trying to do?

4

Wurmloch83 is right and I can debug each line by his way. The reason why it crashed was that I manipulated the pointers in the wrong way. And I do this because I want to reach a hack destination, and it’s that I want to know if a sequencer is playing the audio sections on it.