Remove the ThinLTO CU hack
This reverts #46722, commit e0ab5d5feb.
Since #111167, commit 10b69dde3f, we are
generating DWARF subprograms in a way that is meant to be more compatible
with LLVM's expectations, so hopefully we don't need this workaround
rewriting CUs anymore.
Stop turning transmutes into discriminant reads in mir-opt
Partially reverts #109612, as after #109993 these aren't actually equivalent any more, and I'm no longer confident this was ever an improvement in the first place.
Having this "simplification" meant that similar-looking code actually did somewhat different things. For example,
```rust
pub unsafe fn demo1(x: std::cmp::Ordering) -> u8 {
std::mem::transmute(x)
}
pub unsafe fn demo2(x: std::cmp::Ordering) -> i8 {
std::mem::transmute(x)
}
```
in nightly today is generating <https://rust.godbolt.org/z/dPK58zW18>
```llvm
define noundef i8 `@_ZN7example5demo117h341ef313673d2ee6E(i8` noundef %x) unnamed_addr #0 {
%0 = icmp uge i8 %x, -1
%1 = icmp ule i8 %x, 1
%2 = or i1 %0, %1
call void `@llvm.assume(i1` %2)
ret i8 %x
}
define noundef i8 `@_ZN7example5demo217h5ad29f361a3f5700E(i8` noundef %0) unnamed_addr #0 {
%x = alloca i8, align 1
store i8 %0, ptr %x, align 1
%1 = load i8, ptr %x, align 1, !range !2, !noundef !3
ret i8 %1
}
```
Which feels too different when the original code is essentially identical.
---
Aside: that example is different *after* optimizations too:
```llvm
define noundef i8 `@_ZN7example5demo117h341ef313673d2ee6E(i8` noundef returned %x) unnamed_addr #0 {
%0 = add i8 %x, 1
%1 = icmp ult i8 %0, 3
tail call void `@llvm.assume(i1` %1)
ret i8 %x
}
define noundef i8 `@_ZN7example5demo217h5ad29f361a3f5700E(i8` noundef returned %0) unnamed_addr #1 {
ret i8 %0
}
```
so turning the `Transmute` into a `Discriminant` was arguably just making things worse, so leaving it alone instead -- and thus having less code in rustc -- seems clearly better.
Add a conversion from `&mut T` to `&mut UnsafeCell<T>`
Provides a safe way of downgrading an exclusive reference into an alias-able `&UnsafeCell<T>` reference.
ACP: https://github.com/rust-lang/libs-team/issues/198.
debug format `Const`'s less verbosely
Not user visible change only visible to people debugging const generics.
Currently debug output for `ty::Const` is super verbose (even for `-Zverbose` lol), things like printing infer vars as `Infer(Var(?0c))` instead of just `?0c`, bound vars and placeholders not using `^0_1` or `!0_1` syntax respectively. With these changes its imo better but not perfect:
`Const { ty: usize, kind: ^0_1 }`
is still a lot for not much information. not entirely sure what to do about that so not dealing with it yet.
Need to do formatting for `ConstKind::Expr` at some point too since rn it sucks (doesn't even print anything with `Display`) not gonna do that in this PR either.
r? `@compiler-errors`
Update cargo
8 commits in 13413c64ff88dd6c2824e9eb9374fc5f10895d28..09276c703a473ab33daaeb94917232e80eefd628
2023-05-10 13:46:18 +0000 to 2023-05-16 21:43:35 +0000
- docs: Clarify that crates.io doesn't link to docs.rs right away. (rust-lang/cargo#12146)
- docs(ref): Clarify MSRV is generally minor (rust-lang/cargo#12122)
- Fix `check_for_file_and_add`'s check for conflict file (rust-lang/cargo#12135)
- Fixes: Incorrect document link (rust-lang/cargo#12143)
- doc: intra-doc links and doc comments for build script (rust-lang/cargo#12133)
- Add Cargo team charter. (rust-lang/cargo#12010)
- Remove useless drop of copy type (rust-lang/cargo#12136)
- Fix dep/feat syntax with hidden implicit optional dependencies (rust-lang/cargo#12130)
r? ghost
Rollup of 7 pull requests
Successful merges:
- #107680 (Hide repr attribute from doc of types without guaranteed repr)
- #111488 (Use error term in projection if missing associated item in new solver)
- #111533 (Handle error body in generator layout)
- #111573 (Erase `ReError` properly)
- #111592 (Change Vec examples to not assert exact capacity except where it is guaranteed)
- #111610 (fix(diagnostic): wrap parens for ref impl trait param)
- #111642 ([rustdoc] Only keep impl blocks from bodies)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
[rustdoc] Only keep impl blocks from bodies
Fixes https://github.com/rust-lang/rust/issues/111415.
The problem was that we kept everything inside bodies whereas only impl blocks are actually accessible from outside bodies.
r? `@notriddle`
fix(diagnostic): wrap parens for ref impl trait param
Fixes https://github.com/rust-lang/rust/issues/99597
When parameters are an `impl_trait` which it needed to add trait, and it is a reference, add parentheses to the type of the parameter in the suggestion
Change Vec examples to not assert exact capacity except where it is guaranteed
It was [brought up on discord](https://discord.com/channels/273534239310479360/818964227783262209/1107633959329878077) that the `Vec::into_boxed_slice` example contradicted the `Vec::with_capacity` docs in that the returned `Vec` might have _more_ capacity than requested.
So, to reduce confusion change all the `assert_eq!(vec.capacity(), _)` to `assert!(vec.capacity() >= _)`, except in 4 examples that have guaranteed capacities: `Vec::from_raw_parts`, `Vec::from_raw_parts_in`, `Vec::<()>::with_capacity`,`Vec::<(), _>::with_capacity_in`.
Erase `ReError` properly
Fixes#111341
Since we check whether a type has free regions before erasing (to short circuit unnecesary folding), we need to consider `ReError` as a free region, or else we'll skip it when erasing a type that only mentions `ReError`.
cc `@nnethercote`
Handle error body in generator layout
Fixes#111468
I feel like making this query return `Option<GeneratorLayout>` might be better but had some issues with that approach
Use error term in projection if missing associated item in new solver
We were previously delaying a bug but not bailing, leading to an ICE in the `tcx.type_of(assoc_def.item.def_id)` call below.
Hide repr attribute from doc of types without guaranteed repr
Rustdoc has an undesirable behavior of blindly copying `repr` into the documentation of structs and enums, even when there is no particular repr that the type guarantees to its users. This is a source of confusion for standard library users who assume the fact that a repr is documented means it must be something the standard library promises they can rely on (in transmutes, or FFI).
Some issues on the topic of rustdoc's incorrect handling of `repr`:
- https://github.com/rust-lang/rust/issues/66401
- https://github.com/rust-lang/rust/issues/90435
In places, the standard library currently works around this confusing rustdoc behavior by just omitting `repr(transparent)` altogether even where it should be required if equivalent code were being written outside of the standard library. See #61969.
IMO that is even more confusing, even for standard library maintainers — see https://github.com/rust-lang/rust/pull/105018#discussion_r1058400997. It's also not something that works for other reprs like `C` or `u8` which cannot just be omitted even in standard library code.
This PR tries a different approach for some types that are being currently incorrectly documented with a repr.
> **Warning**
> This PR does not imply that every type that still has a `repr` attribute in its docs after this PR is now public for users to rely on. This PR only tries to reduce harm from this longstanding rustdoc issue.
Always fall back to PartialEq when a constant in a pattern is not recursively structural-eq
Right now we destructure the constant as far as we can, but with this PR we just don't take it apart anymore. This is preparatory work for moving to always using valtrees, as these will just do a single conversion of the constant to a valtree at the start, and if that fails, fall back to `PartialEq`.
This removes a few cases where we emitted the `unreachable pattern` lint, because we stop looking into the constant deeply enough to detect that a constant is already covered by another pattern.
Previous work: https://github.com/rust-lang/rust/pull/70743
This is groundwork towards fixing https://github.com/rust-lang/rust/issues/83085 and https://github.com/rust-lang/rust/issues/105047
