source rust-lang#72163 (comment)

`prefix` should not be mutable.

Change the process from for loop to find, which makes the `prefix` able to be immutable.

…matsakis

Fix hang in lexical_region_resolve

Regionck was stuck in a loop where a region value was changing between two equal regions.

Closes rust-lang#72051

…E0228, r=petrochenkov

add long error explanation for E0228

Add long explanation for the E0228 error code
Part of rust-lang#61137

Let me know if this is wrong at all (or can be written more clearly), I'm still learning Rust.

…an-DPC

Clean up E0581 explanation

r? @Dylan-DPC

…hewjasper

Add doc comment for `rustc_middle::mir::mono::Linkage`

Warn against thread::sleep in async fn

I've seen `thread::sleep` wrecking havoc in async servers. There's already an [issue for clippy](rust-lang/rust-clippy#4377), but the std docs could warn against it too.

…atsakis

Remove UnnormalizedProjection

This was only used for the old chalk integration with chalk-engine

r? @nikomatsakis

…wjasper

docs: remove comment referencing non-existent method

…an-DPC

Clean up E0582 explanation

r? @Dylan-DPC