It seems that cargo wasi uses an outdated version of wasm-opt

[0x7CFE]

I was trying to build parts of the rustc using cargo wasi and found that librustc_expand causes wasm-opt to crash.

I filed an issue WebAssembly/binaryen#2821 but it seems that the most recent version does fine.

Any ideas on why this happens?

[alexcrichton]

This updated quite recently, although there has been one more release since then. Is the fix for your issue in that commit range?

[0x7CFE]

Honestly, I don't know. My experience is that wasm-opt compiled form master works, but the one that is executed by cargo wasi v0.1.22 does not.

I assume that the fix was introduced less than 2 weeks ago.

[alexcrichton]

Can you try running the binary releases from binaryen itself? If that doesn't work then this is likely an issue with binaryen's binary releases I think?