eval_thunk_selector: strange selectee on aarch64 with 9.12.4
## Summary
One of my colleagues is getting panics will running an application on an aarch64 Mac.
The panic is:
```
internal error: eval_thunk_selector: strange selectee 43
```
The backtraces show that this is happening during GC.
As this is happening with 9.12.4, and 9.12.5 is soon to be released with some fixes, I'm hoping that upgrading will just fix this. I'll report back once we have upgraded
The constant sometimes varies
## Steps to reproduce
None yet.
## Expected behavior
Don't panic.
## Environment
* GHC version used: 9.12.4
Optional:
* Operating System: MacOS
* System Architecture: aarch64
issue