…iaskrgr

Rollup of 9 pull requests

Successful merges:

 - rust-lang#135340 (Add `explicit_extern_abis` Feature and Enforce Explicit ABIs)
 - rust-lang#139440 (rustc_target: RISC-V: feature addition batch 2)
 - rust-lang#139667 (cfi: Remove #[no_sanitize(cfi)] for extern weak functions)
 - rust-lang#139828 (Don't require rigid alias's trait to hold)
 - rust-lang#139854 (Improve parse errors for stray lifetimes in type position)
 - rust-lang#139889 (Clean UI tests 3 of n)
 - rust-lang#139894 (Fix `opt-dist` CLI flag and make it work without LLD)
 - rust-lang#139900 (stepping into impls for normalization is unproductive)
 - rust-lang#139915 (replace some #[rustc_intrinsic] usage with use of the libcore declarations)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of rust-lang#139828 - compiler-errors:rigid-trait, r=lcnr

Don't require rigid alias's trait to hold

See test for write-up. TL;DR is that we don't need the trait bound to hold, since we enforce it during WF.

I think this is preferable to introducing (if we even could do so) a more specific hack around coroutine interiors, higher ranked types, etc, since this is just a manifestation of more pervasive issues w/ lifetime erasure in coroutines. This just doesn't manifest in the old solver b/c it doesn't try to prove `T: Trait` holds when rigidly projecting `<T as Trait>::Assoc`.

It's pretty clear that this affects quite a few traits (rust-lang#139763), so I think this needs fixing.

r? lcnr

Fixes rust-lang/trait-system-refactor-initiative#177