Thanks. You’re right, I don’t see anything wrong with this. I see that you’ve printed the out_dtype, that’s causing the error? Do you see anything unusual there?
If I understand the error correctly, the dtype used for cast operation when you call .astype(...) has 0 lanes, which doesn’t normall happen. I would suggest to try and recreate the issue in a smaller test case, like get the dtype, and write a small script to call .astype() directly with that and see if you can reproduce the error.
If you’re able to reproduce the error and it seems like it should work (suggesting some bug in TVM), I would suggest you to file an issue and I can try to fix the problem.