Loading multifunction models on iOS causes a crash

I used the multifunction models feature introduced in iOS 18 to merge three VAE Encoder models with different resolutions into a single model. However, loading this merged model on iOS causes a crash with the error EXC_BAD_ACCESS (code=1, address=0x0). In contrast, merging VAE Decoder models using the same method does not result in crashes. Additionally, merging only two VAE Decoder models with different resolutions also leads to a crash when loaded on iOS. As for the Stable Diffusion Unet model, merging two or even three models does not cause any crashes, and it successfully generates images as expected.

I use the following code to load the model:

let config = MLModelConfiguration()
config.computeUnits = .cpuAndNeuralEngine
config.functionName = "test"
try MLModel(contentsOf: url, configuration: config)