rustc_resolve: allow `use crate_name;` under `uniform_paths`.
Specifically, `use crate_name;` and `use crate_name::{self, ...};` are now allowed, whereas previously there would produce a (false positive) ambiguity error, as the ambiguity detection code was seeing the `crate_name` import as a locally-available definition to conflict with the crate.
r? @petrochenkov cc @aturon @joshtriplett @Centril
Don't reduce E0161 to a warning in NLL migrate mode
This error has been on stable for a while, and allowing such code cause the compile to later ICE (since we can't codegen it). Errors `box UNSIZED EXPR` with unsized locals because it's not compatible with the current evaluation order (create the box before evaluating the expressions).
cc #53469 (fixes the ICE in this case)
cc @qnighy
Fix issue #52475: Make loop detector only consider reachable memory
As [suggested](https://github.com/rust-lang/rust/pull/51702#discussion_r197585664) by @oli-obk `alloc_id`s should be ignored by traversing all `Allocation`s in interpreter memory at a given moment in time, beginning by `ByRef` locals in the stack.
- [x] Generalize the implementation of `Hash` for `EvalSnapshot` to traverse `Allocation`s
- [x] Generalize the implementation of `PartialEq` for `EvalSnapshot` to traverse `Allocation`s
- [x] Commit regression tests
Fixes#52626
Fixes https://github.com/rust-lang/rust/issues/52849
That is, opting to ignore stable `#![feature(..)]`, under my theory
that a reviewer would prefer as much stuff to be bucketed under "ah
another `#![allow(..)]` here." as possible.
that is, I suspect it should be retired because it is testing behavior
(namely a `#[repr(C)] struct Empty;`) that, if I understand correctly,
is undefined.
See also rust-lang/rust#53859.
rustc_typeck: turn `where Type:,` into a WF(Type) predicate, instead of ignoring it.
Fixes#53696, assuming crater doesn't catch anyone using this syntax already.
Allowing an empty list of bounds in the grammar was done for the benefit of macro authors, most of which would *probably* be using it for bounds on type parameters, which are always WF.
r? @nikomatsakis cc @petrochenkov
