Rollup of 4 pull requests
Successful merges:
- #91008 (Adds IEEE 754-2019 minimun and maximum functions for f32/f64)
- #91070 (Make `LLVMRustGetOrInsertGlobal` always return a `GlobalVariable`)
- #91097 (Add spaces in opaque `impl Trait` with more than one trait)
- #91098 (Don't suggest certain fixups (`.field`, `.await`, etc) when reporting errors while matching on arrays )
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Be more thorough in using `ItemObligation` and `BindingObligation` when
evaluating obligations so that we can point at trait bounds that
introduced unfulfilled obligations. We no longer incorrectly point at
unrelated trait bounds (`substs-ppaux.verbose.stderr`).
In particular, we now point at trait bounds on method calls.
We no longer point at "obvious" obligation sources (we no longer have a
note pointing at `Trait` saying "required by a bound in `Trait`", like
in `associated-types-no-suitable-supertrait*`).
Address part of #89418.
Don't abort compilation after giving a lint error
The only reason to use `abort_if_errors` is when the program is so broken that either:
1. later passes get confused and ICE
2. any diagnostics from later passes would be noise
This is never the case for lints, because the compiler has to be able to deal with `allow`-ed lints.
So it can continue to lint and compile even if there are lint errors.
Closes https://github.com/rust-lang/rust/issues/82761. This is a WIP because I have a feeling it will exit with 0 even if there were lint errors; I don't have a computer that can build rustc locally at the moment.
The only reason to use `abort_if_errors` is when the program is so broken that either:
1. later passes get confused and ICE
2. any diagnostics from later passes would be noise
This is never the case for lints, because the compiler has to be able to deal with `allow`-ed lints.
So it can continue to lint and compile even if there are lint errors.
Add #[must_use] to mem/ptr functions
There's a lot of low-level / unsafe stuff here. Are there legit use cases for ignoring any of these return values?
* No regressions in `./x.py test --stage 1 library/std src/tools/clippy`.
* One regression in `./x.py test --stage 1 src/test/ui`. Fixed.
* I am unable to run `./x.py doc` on my machine so I'll need to wait for the CI to verify doctests pass. I eyeballed all the adjacent tests and they all look okay.
Parent issue: #89692
r? ```@joshtriplett```
Suggest a case insensitive match name regardless of levenshtein distance
Fixes#86170
Currently, `find_best_match_for_name` only returns a case insensitive match name depending on a Levenshtein distance. It's a bit unfortunate that that hides some suggestions for typos like `Bar` -> `BAR`. That idea is from https://github.com/rust-lang/rust/pull/46347#discussion_r153701834, but I think it still makes some sense to show a candidate when we find a case insensitive match name as it's more like a typo.
Skipped the `candidate != lookup` check because the current (i.e, `levenshtein_match`) returns the exact same `Symbol` anyway but it doesn't seem to confuse anything on UI tests.
r? ``@estebank``
Remove trailing semicolon from macro call span
Macro call site spans are now less surprising/more consistent since they no longer contain a semicolon after the macro call.
The downside is that we need to do a little guesswork to get the semicolon in diagnostics. But this should not be noticeable since it is rare for the semicolon to not immediately follow the macro call.
move implicit `Sized` predicate to end of list
In `Bounds::predicates()`, move the implicit `Sized` predicate to the
end of the generated list. This means that if there is an explicit
`Sized` bound, it will be checked first, and any resulting
diagnostics will have a more useful span.
Fixes#85998, at least partially. ~~Based on #85979, but only the last 2 commits are new for this pull request.~~ (edit: rebased) A full fix would need to deal with where-clauses, and that seems difficult. Basically, predicates are being collected in multiple stages, and there are two places where implicit `Sized` predicates can be inserted: once for generic parameters, and once for where-clauses. I think this insertion is happening too early, and we should actually do it only at points where we collect all of the relevant trait bounds for a type parameter.
I could use some help interpreting the changes to the stderr output. It looks like reordering the predicates changed some diagnostics that don't obviously have anything to do with `Sized` bounds. Possibly some error reporting code is making assumptions about ordering of predicates? The diagnostics for src/test/ui/derives/derives-span-Hash-*.rs seem to have improved, no longer pointing at the type parameter identifier, but src/test/ui/type-alias-impl-trait/generic_duplicate_param_use9.rs became less verbose for some reason.
I also ran into an instance of #84970 while working on this, but I kind of expected that could happen, because I'm reordering predicates. I can open a separate issue on that if it would be helpful.
``@estebank`` this seems likely to conflict (slightly?) with your work on #85947; how would you like to resolve that?
Show detailed expected/found types in error message when trait paths are the same
Fixes#65230.
### Issue solved by this PR
```rust
trait T {
type U;
fn f(&self) -> Self::U;
}
struct X<'a>(&'a mut i32);
impl<'a> T for X<'a> {
type U = &'a i32;
fn f(&self) -> Self::U {
self.0
}
}
fn main() {}
```
Compiler generates the following note:
```
note: ...so that the types are compatible
--> test.rs:10:28
|
10 | fn f(&self) -> Self::U {
| ____________________________^
11 | | self.0
12 | | }
| |_____^
= note: expected `T`
found `T`
```
This note is not useful since the expected type and the found type are the same.
### How this PR solve the issue
When the expected type and the found type are exactly the same in string representation, the note falls back to the detailed string representation of trait ref:
```
note: ...so that the types are compatible
--> test.rs:10:28
|
10 | fn f(&self) -> Self::U {
| ____________________________^
11 | | self.0
12 | | }
| |_____^
= note: expected `<X<'a> as T>`
found `<X<'_> as T>`
```
So that a user can notice what was different between the expected one and the found one.
Note specific regions involved in 'borrowed data escapes' error
Fixes#67007
Currently, a 'borrowed data escapes' error does not mention
the specific lifetime involved (except indirectly through a suggestion
about adding a lifetime bound). We now explain the specific lifetime
relationship that failed to hold, which improves otherwise vague
error messages.
When encountering a binop where the types would have been accepted, if
all the predicates had been fulfilled, include information about the
predicates and suggest appropriate `#[derive]`s if possible.
Point at trait(s) that needs to be `impl`emented.
Fixes#67007
Currently, a 'borrowed data escapes' error does not mention
the specific lifetime involved (except indirectly through a suggestion
about adding a lifetime bound). We now explain the specific lifetime
relationship that failed to hold, which improves otherwise vague
error messages.
Don't suggest replacing region with 'static in NLL
Fixes#73159
This is similar to #69350 - if the user didn't initially
write out a 'static lifetime, adding 'static in response to
a lifetime error is usually the wrong thing to do.
Fixes#73159
This is similar to #69350 - if the user didn't initially
write out a 'static lifetime, adding 'static in response to
a lifetime error is usually the wrong thing to do.
A subset of places referred to 'super-trait', so this changes them
to all use 'supertrait'. This matches 'supertype' and some other
usages. An exception is 'auto-trait' which is consistently used
in that manner.
Use larger span for adjustment THIR expressions
Currently, we use a relatively 'small' span for THIR
expressions generated by an 'adjustment' (e.g. an autoderef,
autoborrow, unsizing). As a result, if a borrow generated
by an adustment ends up causing a borrowcheck error, for example:
```rust
let mut my_var = String::new();
let my_ref = &my_var
my_var.push('a');
my_ref;
```
then the span for the mutable borrow may end up referring
to only the base expression (e.g. `my_var`), rather than
the method call which triggered the mutable borrow
(e.g. `my_var.push('a')`)
Due to a quirk of the MIR borrowck implementation,
this doesn't always get exposed in migration mode,
but it does in many cases.
This commit makes THIR building consistently use 'larger'
spans for adjustment expressions. These spans are recoded
when we first create the adjustment during typecheck. For
example, an autoref adjustment triggered by a method call
will record the span of the entire method call.
The intent of this change it make it clearer to users
when it's the specific way in which a variable is
used (for example, in a method call) that produdes
a borrowcheck error. For example, an error message
claiming that a 'mutable borrow occurs here' might
be confusing if it just points at a usage of a variable
(e.g. `my_var`), when no `&mut` is in sight. Pointing
at the entire expression should help to emphasize
that the method call itself is responsible for
the mutable borrow.
In several cases, this makes the `#![feature(nll)]` diagnostic
output match up exactly with the default (migration mode) output.
As a result, several `.nll.stderr` files end up getting removed
entirely.
