Reduce HIR debug output
HIR debug output is currently very verbose, especially when used with the alternate (`#`) flag. This commit reduces the amount of noisy newlines by forcing a few small key types to stay on one line, which makes the output easier to read and scroll by.
```
$ rustc +after hello_world.rs -Zunpretty=hir-tree | wc -l
582
$ rustc +before hello_world.rs -Zunpretty=hir-tree | wc -l
932
```
HIR debug output is currently very verbose, especially when used with
the alternate (`#`) flag. This commit reduces the amount of noisy
newlines by forcing a few small key types to stay on one line, which
makes the output easier to read and scroll by.
```
$ rustc +after hello_world.rs -Zunpretty=hir-tree | wc -l
582
$ rustc +before hello_world.rs -Zunpretty=hir-tree | wc -l
932
```
Encode spans relative to the enclosing item -- enable on nightly
Follow-up to #84373 with the flag `-Zincremental-relative-spans` set by default.
This PR seeks to remove one of the main shortcomings of incremental: the handling of spans.
Changing the contents of a function may require redoing part of the compilation process for another function in another file because of span information is changed.
Within one file: all the spans in HIR change, so typechecking had to be re-done.
Between files: spans of associated types/consts/functions change, so type-based resolution needs to be re-done (hygiene information is stored in the span).
The flag `-Zincremental-relative-spans` encodes local spans relative to the span of an item, stored inside the `source_span` query.
Trap: stashed diagnostics are referenced by the "raw" span, so stealing them requires to remove the span's parent.
In order to avoid too much traffic in the span interner, span encoding uses the `ctxt_or_tag` field to encode:
- the parent when the `SyntaxContext` is 0;
- the `SyntaxContext` when the parent is `None`.
Even with this, the PR creates a lot of traffic to the Span interner, when a Span has both a LocalDefId parent and a non-root SyntaxContext. They appear in lowering, when we add a parent to all spans, including those which come from macros, and during inlining when we mark inlined spans.
The last commit changes how queries of `LocalDefId` manage their cache. I can put this in a separate PR if required.
Possible future directions:
- validate that all spans are marked in HIR validation;
- mark macro-expanded spans relative to the def-site and not the use-site.
refactor: merge error code `E0465` into `E0464`
`E0465` is an undocumented and untested error code that is functionally identical to `E0464`. This PR merges `E0465` into `E0464`, thus documenting and testing another error code (#61137).
r? `@GuillaumeGomez` (not sure if you want to review this but it's relevant to my other PRs that you have reviewed)
Revert "Implement allow-by-default `multiple_supertrait_upcastable` lint"
This is a clean revert of #105484.
I confirmed that reverting that PR fixes the regression reported in #106247. ~~I can't say I understand what this code is doing, but maybe it can be re-landed with a different implementation.~~ **Edit:** https://github.com/rust-lang/rust/issues/106247#issuecomment-1367174384 has an explanation of why #105484 ends up surfacing spurious `where_clause_object_safety` errors. The implementation of `where_clause_object_safety` assumes we only check whether a trait is object safe when somebody actually uses that trait with `dyn`. However the implementation of `multiple_supertrait_upcastable` added in the problematic PR involves checking *every* trait for whether it is object-safe.
FYI `@nbdd0121` `@compiler-errors`
CFI: Monomorphize transparent ADTs before typeid
Monomorphise `#[repr(transparent)]` parameterized ADTs before turning them into an Itanium mangled String.
`#[repr(transparent)]` ADTs currently use the single field to represent them in their CFI type ID to ensure that they are compatible. However, if that type involves a type parameter instantiated at the ADT level, as in `ManuallyDrop`, this will currently ICE as the `Parameter` type cannot be mangled. Since this happens at lowering time, it should always be concrete after substitution.
Fixes#106230
The test was minified from the published `msf-ice:0.2.1` crate which failed in a crater run.
A faulty compiler was triggering a `higher-ranked lifetime error`:
> could not prove `[async block@...]: Send`
Migrate more scraped examples CSS rules to CSS variables
It's based on https://github.com/rust-lang/rust/pull/106218 so it will need to wait for it to be merged first.
r? `@notriddle`
Rollup of 9 pull requests
Successful merges:
- #104531 (Provide a better error and a suggestion for `Fn` traits with lifetime params)
- #105899 (`./x doc library --open` opens `std`)
- #106190 (Account for multiple multiline spans with empty padding)
- #106202 (Trim more paths in obligation types)
- #106234 (rustdoc: simplify settings, help, and copy button CSS by not reusing)
- #106236 (docs/test: add docs and a UI test for `E0514` and `E0519`)
- #106259 (Update Clippy)
- #106260 (Fix index out of bounds issues in rustdoc)
- #106263 (Formatter should not try to format non-Rust files)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Monomorphise `#[repr(transparent)]` parameterized ADTs before turning
them into an Itanium mangled String.
`#[repr(transparent)]` ADTs currently use the single field to represent
them in their CFI type ID to ensure that they are compatible. However,
if that type involves a type parameter instantiated at the ADT level, as
in `ManuallyDrop`, this will currently ICE as the `Parameter` type
cannot be mangled. Since this happens at lowering time, it should always
be concrete after substitution.
Fixes#106230
docs/test: add docs and a UI test for `E0514` and `E0519`
No UI test on `E0514`, it would need to compile with a different `rustc` version.
r? `@GuillaumeGomez`
Provide a better error and a suggestion for `Fn` traits with lifetime params
Given `Fn`-family traits with lifetime params in trait bounds like `fn f(_: impl Fn<'a>(&'a str) -> bool)`, we currently produce many unhelpful errors.
This PR allows these situations to suggest simply using Higher-Rank Trait Bounds like `for<'a> Fn(&'a str) -> bool`.
Fixes https://github.com/rust-lang/rust/issues/103490.
Make trait/impl `where` clause mismatch on region error a bit more actionable
Improve `where` clause suggestions for GATs/methods that have incompatible region predicates in their `where` clauses.
Also addresses this diagnostic that went away https://github.com/rust-lang/rust/pull/106129#discussion_r1056875772
Improve heuristics whether `format_args` string is a source literal
Previously, it only checked whether there was _a_ literal at the span of the first argument, not whether the literal actually matched up. This caused issues when a proc macro was generating a different literal with the same span.
This requires an annoying special case for literals ending in `\n` because otherwise `println` wouldn't give detailed diagnostics anymore which would be bad.
Fixes#106191