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
Implement the `min_const_fn` feature gate
cc @RalfJung @eddyb
r? @Centril
implements the feature gate for #53555
I added a hack so the `const_fn` feature gate also enables the `min_const_fn` feature gate. This ensures that nightly users of `const_fn` don't have to touch their code at all.
The `min_const_fn` checks are run first, and if they succeeded, the `const_fn` checks are run additionally to ensure we didn't miss anything.
Fix promotion stability hole in old borrowck
r? @nikomatsakis
I screwed up the promotion stability checks. Big time. They were basically nonexistant. We had tests for it. I also screwed up said tests. This is in stable already :(
Basically stability checks of promotion only worked if you tried to use a const fn defined in the same crate.
cc @eddyb
Allow panicking with string literal messages inside constants
r? @eddyb
cc https://github.com/rust-lang/rust/issues/51999
we can't implement things like `panic!("foo: {}", x)` right now because we can't call trait methods (most notably `Display::fmt`) inside constants. Also most of these impls probably have loops and conditions, so it's messy anyway.
But hey `panic!("foo")` works at least.
cc @japaric got any test ideas for `#![no_std]`?
During the sanity check, we keep track of the path we are below in a `Vec`. We
avoid cloning that `Vec` unless we hit a pointer indirection. The `String`
representation is only computed when validation actually fails.
This commit adds a normalization for line and column numbers in stderr
files where the line/col is from the source directory rather than
the test itself - thereby removing the need to update tests as
compiler source changes.
