Built-in check-fail / failure-status?

[DaniPopes]

Currently there is no built-in flag for //@ check-fail or //@ failure-status <code>, and because config is not mutable it can't be implemented as a custom flag either. How can I best replicate the compiletest behavior?

[oli-obk]

config is not mutable it can't be implemented as a custom flag either.

It should totally be possible. I'll write some docs on how to add custom flags

But yea, these should exist builtin for all configs, not just rustc

[DaniPopes]

I couldn't figure out how then, I see all the methods on Flag accept only &*Config