added more context for duplicate lang item errors (fixes#60561)
Some more information about #60561 -- these errors are pretty common when one works in restrictive environments with `no_std` or customized `std`, but they don't provide much context for debugging, as any transitive dependency could have brought in `std` crate. With that, currently, one needs to use something like `cargo tree` and investigate transitive dependencies one by one.
It'll be more helpful to know at least the crate that uses `std` (which `cargo tree` doesn't show) to pin down this investigation when debugging.
I'm not sure what the best way to get this context is inside rustc internals (I'm new to them). I found that `all_crate_nums` query returns the crates in some dependency order, so printing out the name of the preceding crate seems to do the trick. But I welcome suggestions if this can be done in a better way.
check_match: improve diagnostics for `let A = 2;` with `const A: i32 = 3`
For example:
```
error[E0005]: refutable pattern in local binding: `std::i32::MIN..=1i32` and `3i32..=std::i32::MAX` not covered
--> $DIR/const-pat-non-exaustive-let-new-var.rs:2:9
|
LL | let A = 3;
| ^
| |
| interpreted as a constant pattern, not a new variable
| help: introduce a variable instead: `a_var`
...
LL | const A: i32 = 2;
| ----------------- constant defined here
```
r? @estebank
cc @matthiaskrgr @rpjohnst
hir: Disallow `target_feature` on constants
Fixes#64768.
This PR fixes an ICE when `#[target_feature]` is applied to constants by disallowing this with the same error as when `#[target_feature]` is applied to other places it shouldn't be.
I couldn't see anything in the [RFC](https://github.com/rust-lang/rfcs/blob/master/text/2045-target-feature.md) that suggested that `#[target_feature]` should be applicable to constants or any tests that suggested it should, though I might have missed something - if this is desirable in future, it remains possible to remove this error (but for the time being, I think this error is better than an ICE).
I also added some extra cases to the test for other places where `#[target_feature]` should not be permitted.
cc @gnzlbg
Account for tail expressions when pointing at return type
When there's a type mismatch we make an effort to check if it was
caused by a function's return type. This logic now makes sure to
only point at the return type if the error happens in a tail
expression.
Turn `walk_parent_nodes` method into an iterator.
CC #39968, CC #40799.
Remove unused DepTrackingMap
Deletes some related code (MemoizationMap trait, etc.)
I believe this became unused with red/green incremental introduction, but am uncertain.
There's no longer two distinct gcx and tcx lifetimes which made this
necessary (or, at least, the code compiles -- it's possible we got
better at normalizing, but that seems unlikely).
When there's a type mismatch we make an effort to check if it was
caused by a function's return type. This logic now makes sure to
only point at the return type if the error happens in a tail
expression.
Where possible, the error message includes the name of the crate
that brought in the crate with duplicate lang items (which
helps with debugging). This information is passed on from cstore
using the `extern_crate` query.
Rename `*.node` to `*.kind`, and `hair::Pattern*` to `hair::Pat*`
In both `ast::Expr` and `hir::Expr`:
- Rename `Expr.node` to `Expr.kind`.
- Rename `Pat.node` to `Pat.kind`.
- Rename `ImplItem.node` to `ImplItem.kind`.
- Rename `Lit.node` to `Lit.kind`.
- Rename `TraitItem.node` to `TraitItem.kind`.
- Rename `Ty.node` to `Ty.kind`.
- Rename `Stmt.node` to `Stmt.kind`.
- Rename `Item.node` to `Item.kind`.
- Rename `ForeignItem.node` to `ForeignItem.kind`.
- Rename `MetaItem.node` to `MetaItem.kind`.
Also:
- Rename `hair::FieldPattern` to `hair::FieldPat`.
- Rename `hair::PatternKind` to `hair::PatKind`.
- Rename `hair::PatternRange` to `hair::PatRange`.
- Rename `PatternContext` to `PatCtxt`.
- Rename `PatternTypeProjection` to `PatTyProj`.
- Rename `hair::Pattern` to `hair::Pat`.
These two sets of changes are grouped together to aid with merging. The only changes are renamings.
r? @petrochenkov
Remove tx_to_llvm_workers from TyCtxt
This can be kept within the codegen backend crates entirely -- there's no reason for us to create it outside and attempt to hold it in the (global) context.
Changes here aren't really too easily reviewable I suspect -- not sure if they can be cleaned up by splitting into more commits though, it's just hard to reason about `Box<Any>` in general. If there are thoughts though I'd be happy to hear them.
The primary goal of this PR is to get rid of the field on `rustc_interface::Queries`.
Rename `subst::Kind` to `subst::GenericArg`
And `subst::UnpackedKind` to `subst::GenericArgKind`. Individual variable names (e.g. `kind`) are not renamed, which would be an infeasible mission.
Fixes https://github.com/rust-lang/rust/issues/64352.
r? @eddyb
reserve `impl<T> From<!> for T`
this is necessary for never-type stabilization.
cc #57012#35121
I think we wanted a crater run for this @nikomatsakis?
r? @nikomatsakis
