ChildActor components crash in Streaming levels

Development Programming & Scripting
1

When running Standalone or Packaged builds, the game will crash on load if a streaming level contains an actor with a ChildActor component.

Repro steps:

  1. Create a new project
  2. Add a new streaming level in the Levels panel
  3. Set the streaming level to “Initially Loaded” in the Level Details panel
  4. Create a “Parent” blueprint and a “Child” blueprint
  5. Add a ChildActor component to “Parent” that instantiates a “Child”
  6. Add a “Parent” actor to the streaming level
  7. Run in PIE, note that the game does not crash
  8. Run in Standalone, note that a crash occurs. The game will also crash in Packaged builds.
2

Hey KGist,

I’ve followed your repro, but I’m not seeing the crash occur. Is this happening for you in a clean project?

Also, please provide the following:

  • Logs from your project Saved->Logs folder after the crash occurs
  • Your Machine ID from the crash reporter window, if you are getting one, and ensure to hit Send & Close on the report.

Thanks

3

Hi Sean,

My apologies, I missed a step in my outline. I’ve added a new Step 3 – Set the Streaming Level to “Initially Loaded”. Without this, the Parent blueprint will not be loaded and no crash will occur.

The crash does occur in a completely clean project, using just the steps provided.

Also, the crash occurs however the streaming level is loaded. Rather than setting the level to “Initially Loaded”, you can load it via the “Load Stream Level” blueprint node or use a LevelStreamingVolume to reproduce the crash.

MachineId:B1C3990349070F03349BD28271E22ADF

Thanks,
-Kelson
link text

4

Thanks for the clarification. I’ve tested this repro in a clean project, which I will attach here. I have not seen the crash occurring following your steps at this time. What I’d like you to do is take a look at the attached project and let me know if there are any steps or settings that I’ve missed that may be different from what you have.

Thanks

116908-childactortest+4.14.zip (423 KB)

5

Hi Sean,

Your project is initially crash free for me, as well, but is easily changed to a crashing state.

After the following the crash returned:

  1. Open the Parent blueprint
  2. Select the ChildActor component
  3. Under Child Actor Component, use the Child Actor Class dropdown to set the class to Child (should be a no-op)
  4. Note that a new property (Child Actor Template) appears in the Property panel
  5. The project will now crash when running Standalone

Before:

116914-childactorbefore.png

After:

116915-childactorafter.png

[link text][3]

It’s very strange.

Thanks,
-Kelson

6

I’ve reproduced the crash and entered a bug report, which you can track using the link below:

Thanks for your report.

7

This is still occurring for me in 5.2. It did NOT occur in 4.27 – only after I updated my project to the new engine.

Does anybody have a workaround or solution?

FYI mine crashes in PIE and Simulation too.

Crash log here: Game crash when using AI inside level instances