rust/compiler/rustc_span
bors ce45663e14 Auto merge of #88865 - guswynn:must_not_suspend, r=oli-obk
Implement `#[must_not_suspend]`

implements #83310

Some notes on the impl:

1. The code that searches for the attribute on the ADT is basically copied from the `must_use` lint. It's not shared, as the logic did diverge
2. The RFC does specify that the attribute can be placed on fn's (and fn-like objects), like `must_use`. I think this is a direct copy from the `must_use` reference definition. This implementation does NOT support this, as I felt that ADT's (+ `impl Trait` + `dyn Trait`) cover the usecase's people actually want on the RFC, and adding an imp for the fn call case would be significantly harder. The `must_use` impl can do a single check at fn call stmt time, but `must_not_suspend` would need to answer the question: "for some value X with type T, find any fn call that COULD have produced this value". That would require significant changes to `generator_interior.rs`, and I would need mentorship on that. `@eholk` and I are discussing it.
3. `@estebank` do you know a way I can make the user-provided `reason` note pop out? right now it seems quite hidden

Also, I am not sure if we should run perf on this

r? `@nikomatsakis`
2021-09-22 06:43:33 +00:00
..
src Auto merge of #88865 - guswynn:must_not_suspend, r=oli-obk 2021-09-22 06:43:33 +00:00
Cargo.toml Migrate to 2021 2021-09-20 22:21:42 -04:00