Function passes are completely broken.

[ethanuppal]

Description

Function passes do not work. Module passes work.

To Reproduce

I have reproduced this on a clean macOS 15 docker image. You can reproduce as follows:

1. Open a macOS 15 docker image.
2. Setup Rust/brew.
3. brew install llvm@18 (I tried @17 and @14 too)
4. Copy-paste the hello world example code
5. panic!() in the run_pass implementation function
6. Notice that there is no panic

You can get a panic by putting it right before you register the pass; clearly it is registered since you will be allowed to --passes=hello-world.

Expected behavior

These steps should lead to panic

Screenshots

N/A

Environment

Whatever environment GitHub uses for their macos-15 runners. I tried LLVM 14, 17, and 18.

Additional context