Split rustc_mir
The `rustc_mir` crate is the second largest in the compiler.
This PR splits it up into 5 crates:
- rustc_borrowck;
- rustc_const_eval;
- rustc_mir_dataflow;
- rustc_mir_transform;
- rustc_monomorphize.
Add a regression test for #88649
I noticed that #88649 does not have a regression test, so I add one in this PR.
The test fails with this without #88678:
```
error[E0080]: evaluation of constant value failed
--> /checkout/src/test/ui/consts/issue-88649.rs:13:52
|
LL | Foo::Variant1(x) | Foo::Variant2(x) if x => {}
| ^ StorageLive on a local that was already live
error: aborting due to previous error
For more information about this error, try `rustc --explain E0080`.
```
Improve diagnostics for unary plus operators (#88276)
This pull request improves the diagnostics emitted on parsing a unary plus operator. See #88276.
Before:
```
error: expected expression, found `+`
--> src/main.rs:2:13
|
2 | let x = +1;
| ^ expected expression
```
After:
```
error: leading `+` is not supported
--> main.rs:2:13
|
2 | let x = +1;
| ^
| |
| unexpected `+`
| help: try removing the `+`
```
Suggest deriving traits if possible
This only applies to builtin derives as I don't think there is a
clean way to get the available derives in typeck.
Closes#85851
Remove `hir::GenericBound::Unsized`
Rather than "moving" the `?Sized` bounds to the param bounds, just also check where clauses in `astconv`. I also did some related cleanup here, but that's not strictly neccesary. Also going to do a perf run here.
r? `@estebank`
Fix handling of +whole-archive native link modifier.
This PR fixes a bug in `add_upstream_native_libraries` that led to the `+whole-archive` modifier being ignored when linking in native libs.
~~Note that the PR does not address the situation when `+whole-archive` is combined with `+bundle`.~~
`@wesleywiser's` commit adds validation code that turns combining `+whole-archive` with `+bundle` into an error.
Fixes https://github.com/rust-lang/rust/issues/88085.
r? `@petrochenkov`
cc `@wesleywiser` `@gcoakes`
Change scope of temporaries in match guards
Each pattern in a match arm has its own copy of the match guard in MIR, with its own temporary, so it has to be dropped before the the guards are joined to the single copy of the arm. This PR changes `then_else_break` to allow it to put the temporary in the innermost scope possible. This change isn't done for `if` expressions because that affects a large number of mir-opt tests and could more significantly affect performance.
closes#88649
r? `@oli-obk`
Add tests for some const generics issues
closes#82956closes#84659closes#86530closes#86535
there is also a random test in here about array repeat expressions that I already had on this branch but it seems to fit the theme of this PR so kept it...
r? `@lcnr`
Improve structured tuple struct suggestion
Previously, the span was just for the constructor name, which meant it
would result in syntactically-invalid code when applied. Now, the span
is for the entire expression.
I also changed it to use `span_suggestion_verbose`, for two reasons:
1. Now that the suggestion span has been corrected, the output is a bit
cluttered and hard to read. Putting the suggestion its own window
creates more space.
2. It's easier to see what's being suggested, since now the version
after the suggestion is applied is shown.
r? `@davidtwco`
Avoid invoking the hir_crate query to traverse the HIR
Walking the HIR tree is done using the `hir_crate` query. However, this is unnecessary, since `hir_owner(CRATE_DEF_ID)` provides the same information. Since depending on `hir_crate` forces dependents to always be executed, this leads to unnecessary work.
By splitting HIR and attributes visits, we can avoid an edge to `hir_crate` when trying to visit the HIR tree.
Stop allocating vtable entries for non-object-safe methods
Current a vtable entry is allocated for all associated fns, even if the method is not object-safe: https://godbolt.org/z/h7vx6f35T
As a result, each vtable for `Iterator`' currently consumes 74 `usize`s. This PR stops allocating vtable entries for those methods, reducing vtable size of each `Iterator` vtable to 7 `usize`s.
Note that this PR introduces will cause more invocations of `is_vtable_safe_method`. So a perf run might be needed. If result isn't favorable then we might need to query-ify `is_vtable_safe_method`.
Each pattern in a match arm has its own copy of the match guard in MIR,
with its own temporary, so it has to be dropped before the the guards
are joined to the single copy of the arm.
rustdoc: Clean up handling of lifetime bounds
Previously, rustdoc recorded lifetime bounds by rendering them into the
name of the lifetime parameter. Now, it leaves the name as the actual
name and instead records lifetime bounds in an `outlives` list, similar
to how type parameter bounds are recorded.
Also, higher-ranked lifetimes cannot currently have bounds, so I simplified
the code to reflect that.
r? `@GuillaumeGomez`
Fix 2021 `dyn` suggestion that used code as label
The arguments to `span_suggestion` were in the wrong order, so the error
looked like this:
error[E0783]: trait objects without an explicit `dyn` are deprecated
--> src/test/ui/editions/dyn-trait-sugg-2021.rs:10:5
|
10 | Foo::hi(123);
| ^^^ help: <dyn Foo>: `use `dyn``
Now the error looks like this, as expected:
error[E0783]: trait objects without an explicit `dyn` are deprecated
--> src/test/ui/editions/dyn-trait-sugg-2021.rs:10:5
|
10 | Foo::hi(123);
| ^^^ help: use `dyn`: `<dyn Foo>`
This issue was only present in the 2021 error; the 2018 lint was
correct.
r? `@m-ou-se`
The arguments to `span_suggestion` were in the wrong order, so the error
looked like this:
error[E0783]: trait objects without an explicit `dyn` are deprecated
--> src/test/ui/editions/dyn-trait-sugg-2021.rs:10:5
|
10 | Foo::hi(123);
| ^^^ help: <dyn Foo>: `use `dyn``
Now the error looks like this, as expected:
error[E0783]: trait objects without an explicit `dyn` are deprecated
--> src/test/ui/editions/dyn-trait-sugg-2021.rs:10:5
|
10 | Foo::hi(123);
| ^^^ help: use `dyn`: `<dyn Foo>`
This issue was only present in the 2021 error; the 2018 lint was
correct.
Detect bare blocks with type ascription that were meant to be a `struct` literal
Address part of #34255.
Potential improvement: silence the other knock down errors in `issue-34255-1.rs`.
Add regression test for a spurious import
This PR adds a test that verifies that the bug described in the linked issue does not creep back into the code. In essence it checks that compiling some specific code (that uses 128 bit multiplication) with a specific set of compiler options does not lead to a spurious import of a panic function.
I noticed that other wasm tests use `# only-wasm32-bare` in their `Makefile`. This will skip the test for me. I did not find out how to run this test locally. Maybe someone can help.
closes#78744
r? `@jyn514`
Fix drop handling for `if let` expressions
MIR lowering for `if let` expressions is now more complicated now that
`if let` exists in HIR. This PR adds a scope for the variables bound in
an `if let` expression and then uses an approach similar to how we
handle loops to ensure that we reliably drop the correct variables.
Closes#88307
cc `@flip1995` `@richkadel` `@c410-f3r`
expand: Treat more macro calls as statement macro calls
This PR implements the suggestion from https://github.com/rust-lang/rust/pull/87981#issuecomment-906641052 and treats fn-like macro calls inside `StmtKind::Item` and `StmtKind::Semi` as statement macro calls, which is consistent with treatment of attribute invocations in the same positions and with token-based macro expansion model in general.
This also allows to remove a special case in `NodeId` assignment (previously tried in #87779), and to use statement `NodeId`s for linting (`assign_id!`).
r? `@Aaron1011`
Point at unclosed delimiters as part of the primary MultiSpan
Both the place where the parser encounters a needed closed delimiter and
the unclosed opening delimiter are important, so they should get the
same level of highlighting in the output.
_Context: https://twitter.com/mwk4/status/1430631546432675840_
Path remapping: Make behavior of diagnostics output dependent on presence of --remap-path-prefix.
This PR fixes a regression (#87745) with `--remap-path-prefix` where the flag stopped causing diagnostic messages to be remapped as well. The regression was introduced in https://github.com/rust-lang/rust/pull/83813 where we erroneously assumed that remapping of diagnostic messages was not desired anymore (because #70642 partially undid that functionality with nobody objecting).
The issue is fixed by making `--remap-path-prefix` remap diagnostic messages again, including for paths that have been remapped in upstream crates (e.g. the standard library). This means that "sysroot-localization" (implemented in #70642) is also disabled if `rustc` is invoked with `--remap-path-prefix`. The assumption is that once someone starts explicitly remapping paths they also don't want paths to their local Rust installation in their build output.
In the future we might want to give more fine-grained control over this behavior via compiler flags (see https://github.com/rust-lang/rfcs/pull/3127 for a related RFC). For now this PR is intended as a regression fix.
This PR is an alternative to https://github.com/rust-lang/rust/pull/88191, which makes diagnostic messages be remapped unconditionally. That approach, however, would effectively revert #70642.
Fixes https://github.com/rust-lang/rust/issues/87745.
cc `@cbeuw`
r? `@ghost`