Physics Substep causing crash

After enabling physics substeps in Project settings: Max Substep Delta Time: 0.007000, Max Substep: 6, I’m starting to get random crashes at the same line:

PxRigidBody* FBodyInstance::GetPxRigidBody_AssumesLocked() const
	// The logic below works because dynamic actors are non-NULL in only one scene.
	// If this assumption changes, the logic needs to change.
	PxRigidActor* RigidActor = RigidActorSync ? RigidActorSync : RigidActorAsync;
	return RigidActor ? RigidActor->is<PxRigidBody>() : nullptr;

Since the crash occur at the last line: return RigidActor ? RigidActor->is() : nullptr;

I suspect the variable RigidActor is invalid for some reason?

Can Epic staff confirm whether this is a bug or not? And how can I fix this issue?

Thank you.


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After some testing, I found out this random crash only occurs when I apply force to destructible actors. Since the code is checking for validity of RigidActorAsync, I suspect it has something to do with destructible/debris physics.

So I turn on Project Settings > Physics > Enable Async Scene

after that, I didn’t get the same crashes for 1 week, I’ll see if this really fix the issue and report back.