Rollup of 10 pull requests
Successful merges:
- #87818 (Fix anchors display in rustdoc)
- #87983 (Use more accurate spans when proposing adding lifetime to item)
- #88012 (Change WASI's `RawFd` from `u32` to `c_int` (`i32`).)
- #88031 (Make `BuildHasher` object safe)
- #88036 (Fix dead code warning when inline const is used in pattern)
- #88082 (Take into account jobs number for rustdoc GUI tests)
- #88109 (Fix environment variable getter docs)
- #88111 (Add background-color on clickable definitions in source code)
- #88129 (Fix dataflow graphviz bug, make dataflow graphviz modules public)
- #88136 (Move private_unused.rs test to impl-trait)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Matthew's work on improving NLL's "higher-ranked subtype error"s
This PR rebases `@matthewjasper's` [branch](https://github.com/matthewjasper/rust/tree/nll-hrtb-errors) which has great work to fix the obscure higher-ranked subtype errors that are tracked in #57374.
These are a blocker to turning full NLLs on, and doing some internal cleanups to remove some of the old region code.
The goal is so `@nikomatsakis` can take a look at this early, and I'll then do my best to help do the changes and followup work to land this work, and move closer to turning off the migration mode.
I've only updated the branch and made it compile, removed a warning or two.
r? `@nikomatsakis`
(Here's the [zulip topic to discuss this](https://rust-lang.zulipchat.com/#narrow/stream/122657-t-compiler.2Fwg-nll/topic/.2357374.3A.20improving.20higher-ranked.20subtype.20errors.20via.20.2386700) that Niko wanted)
Update `polonius-engine` to 0.13.0
This PR updates the use of `polonius-engine` to the recently released 0.13.0:
- this version renamed a lot of relations to match the current terminology
- "illegal subset relationships errors" (AKA "subset errors" or "universal region errors" in rustc parlance) have been implemented in all variants, and therefore the `Hybrid` variant can be the rustc default once again
- some of the blessed expectations were updated: new tests have been added since the last time I updated the tests, diagnostics have changed, etc.
In particular:
- a few tests had trivial expectations changes such as basic diagnostics changes for the migrate-mode and full NLLs
- others were recursion and lengths limits which emits a file, and under the polonius compare-mode, the folder has a different name
- a few tests were ignored in the NLL compare-mode for reasons that obviously also apply to Polonius
- some diagnostics were unified so that older expectations no longer made sense: the NLL and Polonius outputs were identical.
- in a few cases Polonius gets a chance to emit more errors than NLLs
A few tests in the compare-mode still are super slow and trigger the 60s warning, or OOM rustc during fact generation, and I've detailed these [on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/186049-t-compiler.2Fwg-polonius/topic/Challenges.20for.20move.2Finit.2C.20liveness.2C.20and.20.60Location.3A.3AAll.60):
- `src/test/ui/numbers-arithmetic/saturating-float-casts.rs` -> OOM during rustc fact generation
- `src/test/ui/numbers-arithmetic/num-wrapping.rs`
- `src/test/ui/issues/issue-72933-match-stack-overflow.rs`
- `src/test/ui/issues/issue-74564-if-expr-stack-overflow.rs`
- `src/test/ui/repr/repr-no-niche.rs`
In addition, 2 tests don't currently pass and I didn't want to bless them now: they deal with HRTBs and miss errors that NLLs emit. We're currently trying to see if we need chalk to deal with HRTB errors (as we thought we would have to) but during the recent sprint, we discovered that we may be able to detect some of these errors in a way that resembles subset errors:
- `ui/hrtb/hrtb-just-for-static.rs` -> 3 errors in NLL, 2 in polonius: a missing error about HRTB + needing to outlive 'static
- `ui/issues/issue-26217.rs` -> missing HRTB that makes the test compile instead of emitting an error
We'll keep talking about this at the next sprint as well.
cc `@rust-lang/wg-polonius` r? `@nikomatsakis`
Move some UI tests to more suitable subdirs
The classifui result: https://gist.github.com/JohnTitor/c9e00840990b5e4a8fc562ec3571e427/e06c42226c6038da91e403c33b9947843420cf44
Some notes:
- backtrace-debuginfo.rs: previously I skipped this, I'm still not sure what the best dir is. Any ideas?
- estr-subtyping.rs: Seems a quite old test so removed, shouldn't?
- deref-suggestion.rs: moved to inference as `suggestions` is not an ideal dir.
- issue-43023.rs: a bit misclassified, moved to `derives`
cc #73494
r? `@petrochenkov`
Link to edition guide instead of issues for 2021 lints.
This changes the 2021 lints to not link to github issues, but to the edition guide instead.
Fixes #86996
* On suggestions that include deletions, use a diff inspired output format
* When suggesting addition, use `+` as underline
* Color highlight modified span
Add hint for unresolved associated trait items if the trait has a single item
This PR introduces a special-cased hint for unresolved trait items paths. It is shown if:
- the path was not resolved to any existing trait item
- and no existing trait item's name was reasonably close with regard to edit distance
- and the trait only has a single item in the corresponding namespace
I didn't know where I should put tests, therefore so far I just managed to bless two existing tests. I would be glad for hints where should tests for a hint like this be created, how should they be named (with reference to the original issue?) and what tests should I create (is it enough to test it just for types? or create separate tests also for functions and constants?).
It could also be turned into a machine applicable suggestion I suppose.
This is my first `rustc` PR, so please go easy on me :)
Fixes: https://github.com/rust-lang/rust/issues/87638
Trait upcasting coercion (part1)
This revives the first part of earlier PR #60900 .
It's not very clear to me which parts of that pr was design decisions, so i decide to cut it into pieces and land them incrementally. This allows more eyes on the details.
This is the first part, it adds feature gates, adds feature gates tests, and implemented the unsize conversion part.
(I hope i have dealt with the `ExistentialTraitRef` values correctly...)
The next part will be implementing the pointer casting.
Store all HIR owners in the same container
This replaces the previous storage in a BTreeMap for each of Item/ImplItem/TraitItem/ForeignItem.
This should allow for a more compact storage.
Based on https://github.com/rust-lang/rust/pull/83114
Remove detection of rustup and cargo in 'missing extern crate' diagnostics
Previously, this would change the test output when RUSTUP_HOME was set:
```
---- [ui] ui/issues/issue-49851/compiler-builtins-error.rs stdout ----
diff of stderr:
1 error[E0463]: can't find crate for `core`
2 |
3 = note: the `thumbv7em-none-eabihf` target may not be installed
+ = help: consider downloading the target with `rustup target add thumbv7em-none-eabihf`
4
5 error: aborting due to previous error
6
```
Originally, I fixed it by explicitly unsetting RUSTUP_HOME in
compiletest. Then I realized that almost no one has RUSTUP_HOME set,
since rustup doesn't set it itself. It does set RUST_RECURSION_COUNT
whenever it launches a proxy, though - use that instead.
r? ```@estebank``` cc ```@petrochenkov``` ```@kinnison```
Previously, this would change the test output when RUSTUP_HOME was set:
```
---- [ui] ui/issues/issue-49851/compiler-builtins-error.rs stdout ----
diff of stderr:
1 error[E0463]: can't find crate for `core`
2 |
3 = note: the `thumbv7em-none-eabihf` target may not be installed
+ = help: consider downloading the target with `rustup target add thumbv7em-none-eabihf`
4
5 error: aborting due to previous error
6
```
Originally, I fixed it by explicitly unsetting RUSTUP_HOME in
compiletest. Then I realized that almost no one has RUSTUP_HOME set,
since rustup doesn't set it itself; although it does set RUST_RECURSION_COUNT
whenever it launches a proxy. Then it was pointed out that this runtime
check doesn't really make sense and it's fine to make it unconditional.
Support HIR wf checking for function signatures
During function type-checking, we normalize any associated types in
the function signature (argument types + return type), and then
create WF obligations for each of the normalized types. The HIR wf code
does not currently support this case, so any errors that we get have
imprecise spans.
This commit extends `ObligationCauseCode::WellFormed` to support
recording a function parameter, allowing us to get the corresponding
HIR type if an error occurs. Function typechecking is modified to
pass this information during signature normalization and WF checking.
The resulting code is fairly verbose, due to the fact that we can
no longer normalize the entire signature with a single function call.
As part of the refactoring, we now perform HIR-based WF checking
for several other 'typed items' (statics, consts, and inherent impls).
As a result, WF and projection errors in a function signature now
have a precise span, which points directly at the responsible type.
If a function signature is constructed via a macro, this will allow
the error message to point at the code 'most responsible' for the error
(e.g. a user-supplied macro argument).
Fix implicit Sized relaxation when attempting to relax other, unsupported trait
Fixes#87199.
Do note that this bug fix causes code like the `ref_arg::<[i32]>(&[5]);` line in the test case in combination with an affected function to no longer compile.
When pretty printing, name placeholders as bound regions
Split from #85499
When we see a placeholder that we are going to print, treat it as a bound var (and add it to a `for<...>`
During function type-checking, we normalize any associated types in
the function signature (argument types + return type), and then
create WF obligations for each of the normalized types. The HIR wf code
does not currently support this case, so any errors that we get have
imprecise spans.
This commit extends `ObligationCauseCode::WellFormed` to support
recording a function parameter, allowing us to get the corresponding
HIR type if an error occurs. Function typechecking is modified to
pass this information during signature normalization and WF checking.
The resulting code is fairly verbose, due to the fact that we can
no longer normalize the entire signature with a single function call.
As part of the refactoring, we now perform HIR-based WF checking
for several other 'typed items' (statics, consts, and inherent impls).
As a result, WF and projection errors in a function signature now
have a precise span, which points directly at the responsible type.
If a function signature is constructed via a macro, this will allow
the error message to point at the code 'most responsible' for the error
(e.g. a user-supplied macro argument).
Better diagnostics with mismatched types due to implicit static lifetime
Fixes#78113
I think this is my first diagnostics PR...definitely happy to hear thoughts on the direction/implementation here.
I was originally just trying to solve the error above, where the lifetime on a GAT was causing a cryptic "mismatched types" error. But as I was writing this, I realized that this (unintentionally) also applied to a different case: `wf-in-foreign-fn-decls-issue-80468.rs`. I'm not sure if this diagnostic should get a new error code, or even reuse an existing one. And, there might be some ways to make this even more generalized. Also, the error is a bit more lengthy and verbose than probably needed. So thoughts there are welcome too.
This PR essentially ended up adding a new nice region error pass that triggers if a type doesn't match the self type of an impl which is selected because of a predicate because of an implicit static bound on that self type.
r? `@estebank`
Various diagnostics clean ups/tweaks
* Always point at macros, including derive macros
* Point at non-local items that introduce a trait requirement
* On private associated item, point at definition
* Always point at macros, including derive macros
* Point at non-local items that introduce a trait requirement
* On private associated item, point at definition
