Spruce up the diagnostics of some early lints
Implement the various "*(note to myself) in a follow-up PR we should turn parts of this message into a subdiagnostic (help msg or even struct sugg)*" drive-by comments I left in #124417 during my review.
For context, before #124417, only a few early lints touched/decorated/customized their diagnostic because the former API made it a bit awkward. Likely because of that, things that should've been subdiagnostics were just crammed into the primary message. This PR rectifies this.
Only compute `specializes` query if (min)specialization is enabled in the crate of the specializing impl
Fixes (after backport) https://github.com/rust-lang/rust/issues/125197
### What
https://github.com/rust-lang/rust/pull/122791 makes it so that inductive cycles are no longer hard errors. That means that when we are testing, for example, whether these impls overlap:
```rust
impl PartialEq<Self> for AnyId {
fn eq(&self, _: &Self) -> bool {
todo!()
}
}
impl<T: Identifier> PartialEq<T> for AnyId {
fn eq(&self, _: &T) -> bool {
todo!()
}
}
```
...given...
```rust
pub trait Identifier: Display + 'static {}
impl<T> Identifier for T where T: PartialEq + Display + 'static {}
```
Then we try to see if the second impl holds given `T = AnyId`. That requires `AnyId: Identifier`, which requires that `AnyId: PartialEq`, which is satisfied by these two impl candidates... The `PartialEq<T>` impl is a cycle, and we used to winnow it when we used to treat inductive cycles as errors.
However, now that we don't winnow it, this means that we *now* try calling `candidate_should_be_dropped_in_favor_of`, which tries to check whether one of the impls specializes the other: the `specializes` query. In that query, we currently bail early if the impl is local.
However, in a foreign crate, we try to compute if the two impls specialize each other by doing trait solving. This may itself lead to the same situation where we call `specializes`, which will lead to a query cycle.
### How does this fix the problem
We now record whether specialization is enabled in foreign crates, and extend this early-return behavior to foreign impls too. This means that we can only encounter these cycles if we truly have a specializing impl from a crate with specialization enabled.
-----
r? `@oli-obk` or `@lcnr`
Add `SingleUseConsts` mir-opt pass
The goal here is to make a pass that can be run in debug builds to simplify the common case of constants that are used just once -- that doesn't need SSA handling and avoids any potential downside of multi-use constants. In particular, to simplify the `if T::IS_ZST` pattern that's common in the standard library.
By also handling the case of constants that are *never* actually used this fully replaces the `ConstDebugInfo` pass, since it has all the information needed to do that naturally from the traversal it needs to do anyway.
This is roughly a wash on instructions on its own (a couple regressions, a few improvements https://github.com/rust-lang/rust/pull/125910#issuecomment-2144963361), with a bunch of size improvements. So I'd like to land it as its own PR, then do follow-ups to take more advantage of it (in the inliner, cg_ssa, etc).
r? `@saethlin`
run-make: add `run_in_tmpdir` self-test
Add a basic sanity test for `run_in_tmpdir` to make sure that files (including read-only files) and directories created inside the "scratch" tmpdir are removed after the closure returns.
r? ghost (while i run a try job)
try-job: x86_64-msvc
Add explanatory note to async block type mismatch error
The async block type mismatch error might leave the user wondering as to why it occurred. The new note should give them the needed context.
Changes this diagnostic:
```
error[E0308]: mismatched types
--> src/main.rs:5:23
|
2 | let a = async { 1 };
| ----------- the expected `async` block
3 | let b = async { 2 };
| ----------- the found `async` block
4 |
5 | let bad = vec![a, b];
| ^ expected `async` block, found a different `async` block
|
= note: expected `async` block `{async block@src/main.rs:2:13: 2:24}`
found `async` block `{async block@src/main.rs:3:13: 3:24}`
```
to this:
```
error[E0308]: mismatched types
--> src/main.rs:5:23
|
2 | let a = async { 1 };
| ----------- the expected `async` block
3 | let b = async { 2 };
| ----------- the found `async` block
4 |
5 | let bad = vec![a, b];
| ^ expected `async` block, found a different `async` block
|
= note: expected `async` block `{async block@src/main.rs:2:13: 2:24}`
found `async` block `{async block@src/main.rs:3:13: 3:24}`
= note: no two async blocks, even if identical, have the same type
= help: consider pinning your async block and and casting it to a trait object
```
Fixes#125737
migrate tests/run-make/llvm-outputs to use rmake.rs
part of #121876
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Fix ICE due to `unwrap` in `probe_for_name_many`
Fixes#125876
Now `probe_for_name_many` bubbles up the error returned by `probe_op` instead of calling `unwrap` on it.
rustdoc: Add support for --remap-path-prefix
Adds `--remap-path-prefix` as an unstable option. This is implemented to mimic the behavior of `rustc`'s `--remap-path-prefix`.
This flag similarly takes in two paths, a prefix to replace and a replacement string.
This is useful for build tools (e.g. Buck) other than cargo that can run doc tests.
cc: `@dtolnay`
Rollup of 4 pull requests
Successful merges:
- #126172 (Weekly `cargo update`)
- #126176 (rustdoc-search: use lowercase, non-normalized name for type search)
- #126190 (Autolabel run-make tests, remind to update tracking issue)
- #126194 (Migrate more things to `WinError`)
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc-search: use lowercase, non-normalized name for type search
The type name ID map has underscores in its names, so the query element should have them, too.
Fixes#125993
Remove hard-coded hashes from codegen tests
This removes hard-coded hashes from the codegen and assembly tests. These use FileCheck, which supports eliding part of the pattern being matched, including by capturing it as a pattern parameter for later matching-on. This is much more appropriate than asking contributors to engage with deliberately-opaque identifier schemes.
In order to reduce the likelihood of error, every hash-coded segment I've touched now expects a certain length. This correctly represents these cases, as our hash outputs have a predetermined amount of entropy attached to them.
This is not done for the UI test suite as those are comparatively easy to simply `--bless`, whereas that would be inappropriate for codegen tests. It is also not done for debuginfo tests as those tests do not support such elision in a correct and useful way.
Enable GVN for `AggregateKind::RawPtr`
Looks like I was worried for nothing; this seems like it's much easier than I was originally thinking it would be.
r? `@cjgillot`
This should be useful for `x[..4]`-like things, should those start inlining enough to expose the lengths.
Adds --remap-path-prefix as an unstable option. This is implemented to
mimic the behavior of rustc's --remap-path-prefix but with minor
adjustments.
This flag similarly takes in two paths, a prefix to replace and a
replacement string.
Rollup of 5 pull requests
Successful merges:
- #126137 (tests: Add ui/higher-ranked/trait-bounds/normalize-generic-arg.rs)
- #126146 (std::unix::process adding few specific freebsd signals to be able to id.)
- #126155 (Remove empty test suite `tests/run-make-fulldeps`)
- #126168 (std::unix::os current_exe implementation simplification for haiku.)
- #126175 (Use --quiet flag when installing pip dependencies)
r? `@ghost`
`@rustbot` modify labels: rollup
Remove empty test suite `tests/run-make-fulldeps`
After #109770, there were only a handful of tests left in the run-make-fulldeps suite.
As of #126111, there are no longer *any* run-make-fulldeps tests, so now we can:
- Remove the directory
- Remove related bootstrap/compiletest code
- Remove various other references in CI scripts and documentation.
By removing this suite, we also no longer need to worry about discrepancies between it and ui-fulldeps, and we don't have to worry about porting tests from Makefile to [rmake](https://github.com/rust-lang/rust/issues/121876) (or whether rmake even works with fulldeps).
tests: Add ui/higher-ranked/trait-bounds/normalize-generic-arg.rs
This adds a regression test for an ICE "accidentally" fixed by https://github.com/rust-lang/rust/pull/101947 that does not add a test for this particular case.
Closes#107564.
I have confirmed the added test code fails with `nightly-2023-01-09` (and passes with `nightly-2023-01-10` and of course recent `nightly`).
simd packed types: remove outdated comment, extend codegen test
It seems like https://github.com/rust-lang/rust/pull/125311 made that check in codegen unnecessary?
r? `@workingjubilee` `@calebzulawski`
