As bonus this makes the errors when failing to load a proc macro more
informative to match the backend loading errors. In addition it makes it
slightly easier to patch rustc to work on platforms that don't support
dynamic linking like wasm.
match lowering: simplify empty candidate selection
In match lowering, `match_simplified_candidates` is tasked with removing candidates that are fully matched and linking them up properly. The code that does that was needlessly complicated; this PR simplifies it.
The overall change isn't big but I split it up into tiny commits to convince myself that I was correctly preserving behavior. The test changes are all due to the first commit. Let me know if you'd prefer me to split up the PR to make reviewing easier.
r? `@matthewjasper`
match lowering: eagerly simplify match pairs
This removes one important complication from match lowering. Before this, match pair simplification (which includes collecting bindings and type ascriptions) was intertwined with the whole match lowering algorithm.
I'm avoiding this by storing in each `MatchPair` the sub-`MatchPair`s that correspond to its subfields. This makes it possible to simplify everything (except or-patterns) in `Candidate::new()`.
This should open up further simplifications. It will also give us proper control over the order of bindings.
r? `@matthewjasper`
Rollup of 7 pull requests
Successful merges:
- #119203 (Correct the simd_masked_{load,store} intrinsic docs)
- #121277 (Refactor trait implementations in `core::convert::num`.)
- #121322 (Don't ICE when hitting overflow limit in fulfillment loop in next solver)
- #121323 (Don't use raw parameter types in `find_builder_fn`)
- #121344 (Expand weak alias types before collecting constrained/referenced late bound regions + refactorings)
- #121350 (Fix stray trait mismatch in `resolve_associated_item` for `AsyncFn`)
- #121352 (docs: add missing "the" to `str::strip_prefix` doc)
Failed merges:
- #121340 (bootstrap: apply most of clippy's suggestions)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix stray trait mismatch in `resolve_associated_item` for `AsyncFn`
Copy-paste error meant that we were calling `fn_trait_kind_from_def_id` instead of `async_fn_trait_kind_from_def_id`. But turns out we don't even need to do that, since we already matched the trait def id above.
Fixes#121306
r? oli-obk
Don't use raw parameter types in `find_builder_fn`
We shouldn't really ever be using `EarlyBinder::skip_binder` then performing type equality, since param types will never be equal to other types. When checking compatibility with the signature, we instead create some fresh args.
Fixes#121314
Don't ICE when hitting overflow limit in fulfillment loop in next solver
As the title says, let's not ICE when hitting the overflow limit in fulfill. On the other hand, we don't want to treat these as true errors, since it means that whether something is considered a true error or an ambiguity is dependent on overflow handling in the solver, which seems not worth it.
Now that we use the presence of true errors in fulfillment for implicit negative coherence, we especially don't want to tie together coherence and overflow.
I guess I could also drain these errors out of fulfillment and put them into some `ambiguities` storage so we could return them in `select_all_or_error` without having to re-process them every time we call `select_where_possible`. Let me know if that's desired.
r? lcnr
Refactor trait implementations in `core::convert::num`.
Tracking issue: https://github.com/rust-lang/rust/issues/120257
Implement conversion traits using generic `NonZero` type, and refactor all macros to use a consistent format/order of parameters.
r? `@dtolnay`
Correct the simd_masked_{load,store} intrinsic docs
Explains the uniform pointer being used for these two operations and how elements are offset from it.
Trigger `unsafe_code` lint on invocations of `global_asm`
`unsafe_code` already warns about things that don't involve the `unsafe` keyword, e.g. `#[no_mangle]`. This makes it warn on `core::arch::global_asm` too.
Fixes#103078
Rename `ConstPropLint` to `KnownPanicsLint`
`OverflowLint` is a clearer name because it communicates what the lint does instead of the underlying mechanism it uses (const propagation) which should be of secondary concern.
`OverflowLint` isn't the most accurate name because the lint looks for other errors as well such as division by zero not just overflows, but I couldn't think of another equally succinct name.
As a part of this change. I've also added/updated some of the comments.
cc ```@RalfJung``` ```@oli-obk``` for visibility in case you go looking for the lint using the old name.
Edit:
Changed the name from `OverflowLint` to `KnownPanicsLint`
Remove the "codegen" profile from bootstrap
This profile originally made sense when download-ci-llvm = if-unchanged didn't exist and we had the bad tradeoff of "never modify or always compile".
Thankfully, these grim times are over and we have discovered clean water, so the only differentiator between the two profiles is the codegen profile having LLVM assertions. Adding them doesn't cause that much of a slowdown, <10% on UI tests from an unscientific benchmark.
It also had LLVM warnings when compiling, which makes sense for every compiler contributor brave enough to compile LLVM.
The way I removed is by just issueing a nice error message. Given that everyone with this profile should be a contributor and not someone like a distro who is more upset when things break, this should be fine. If it isn't, we can always fall back to just letting codegen mean compiler.
Always inline check in `assert_unsafe_precondition` with cfg(debug_assertions)
The current complexities in `assert_unsafe_precondition` are delicately balancing several concerns, among them compile times for the cases where there are no debug assertions. This comes at a large runtime cost when the assertions are enabled, making the debug assertion compiler a lot slower, which is very annoying.
To avoid this, we always inline the check when building with debug assertions.
Numbers (compiling stage1 library after touching core):
- master: 80s
- just adding `#[inline(always)]` to the `cfg(bootstrap)` `debug_assertions` (equivalent to a bootstrap bump (uhh, i just realized that i was on a slightly outdated master so this bump might have happened already), (#121112)): 67s
- this: 54s
So this seems like a good solution. I think we can still get the same run-time perf improvements for other users too by massaging this code further (see my other PR about adding `#[rustc_no_mir_inline]` #121114) but this is a simpler step that solves the imminent problem of "holy shit my rustc is sooo slow".
Funny consequence: This now means compiling the standard library with dbeug assertions makes it faster (than without, when using debug assertions downstream)!
r? ```@saethlin``` (or anyone else if someone wants to review this)
fixes#121110, supposedly
Use intrinsics::debug_assertions in debug_assert_nounwind
This is the first item in https://github.com/rust-lang/rust/issues/120848.
Based on the benchmarking in this PR, it looks like, for the programs in our benchmark suite, enabling all these additional checks does not introduce significant compile-time overhead, with the single exception of `Alignment::new_unchecked`. Therefore, I've added `#[cfg(debug_assertions)]` to that one call site, so that it remains compiled out in the distributed standard library.
The trailing commas in the previous calls to `debug_assert_nounwind!` were causing the macro to expand to `panic_nouwnind_fmt`, which requires more work to set up its arguments, and that overhead alone is measured between this perf run and the next: https://github.com/rust-lang/rust/pull/120863#issuecomment-1937423502
Overhaul `Diagnostic` and `DiagnosticBuilder`
Implements the first part of https://github.com/rust-lang/compiler-team/issues/722, which moves functionality and use away from `Diagnostic`, onto `DiagnosticBuilder`.
Likely follow-ups:
- Move things around, because this PR was written to minimize diff size, so some things end up in sub-optimal places. E.g. `DiagnosticBuilder` has impls in both `diagnostic.rs` and `diagnostic_builder.rs`.
- Rename `Diagnostic` as `DiagInner` and `DiagnosticBuilder` as `Diag`.
r? `@davidtwco`
Always evaluate free constants and statics, even if previous errors occurred
work towards https://github.com/rust-lang/rust/issues/79738
We will need to evaluate static items before the `definitions.freeze()` below, as we will start creating new `DefId`s (for nested allocations) within the `eval_static_initializer` query.
But even without that motivation, this is a good change. Hard errors should always be reported and not silenced if other errors happened earlier.
Rollup of 10 pull requests
Successful merges:
- #120716 (Change leak check and suspicious auto trait lint warning messages)
- #121195 (unstable-book: Separate testing and production sanitizers)
- #121205 (Merge `CompilerError::CompilationFailed` and `CompilerError::ICE`.)
- #121233 (Move the extra directives for `Mode::CoverageRun` into `iter_header`)
- #121256 (Allow AST and HIR visitors to return `ControlFlow`)
- #121307 (Drive-by `DUMMY_SP` -> `Span` and fmt changes)
- #121308 (Add regression test for #103369)
- #121310 (Remove an old hack for rustdoc)
- #121311 (Make `is_nonoverlapping` `#[inline]`)
- #121319 (return `ty::Error` when equating `ty::Error`)
r? `@ghost`
`@rustbot` modify labels: rollup
return `ty::Error` when equating `ty::Error`
This helps iron out a difference in diagnostics between `Sub` and `Equate` relations, which I'm currently trying to unify.
r? oli-obk
Drive-by `DUMMY_SP` -> `Span` and fmt changes
Noticed these while doing something else. There's no practical change, but it's preferable to use `DUMMY_SP` as little as possible, particularly when we have perfectlly useful `Span`s available.
Allow AST and HIR visitors to return `ControlFlow`
Alternative to #108598.
Since rust-lang/libs-team#187 was rejected, this implements our own version of the `Try` trait (`VisitorResult`) and the `try` macro (`try_visit`). Since this change still allows visitors to return `()`, no changes have been made to the existing ones. They can be done in a separate PR.
Move the extra directives for `Mode::CoverageRun` into `iter_header`
When these extra directives were ported over as part of #112300, it made sense to introduce `iter_header_extra` and pass them in as an extra argument.
But now that #120881 has added a `mode` parameter to `iter_header` for its own purposes, it's slightly simpler to move the coverage special-case code directly into `iter_header` as well. This lets us get rid of `iter_header_extra`.
Merge `CompilerError::CompilationFailed` and `CompilerError::ICE`.
`CompilerError` has `CompilationFailed` and `ICE` variants, which seems reasonable at first. But the way it identifies them is flawed:
- If compilation errors out, i.e. `RunCompiler::run` returns an `Err`, it uses `CompilationFailed`, which is reasonable.
- If compilation panics with `FatalError`, it catches the panic and uses `ICE`. This is sometimes right, because ICEs do cause `FatalError` panics, but sometimes wrong, because certain compiler errors also cause `FatalError` panics. (The compiler/rustdoc/clippy/whatever just catches the `FatalError` with `catch_with_exit_code` in `main`.)
In other words, certain non-ICE compilation failures get miscategorized as ICEs. It's not possible to reliably distinguish the two cases, so this commit merges them. It also renames the combined variant as just `Failed`, to better match the existing `Interrupted` and `Skipped` variants.
Here is an example of a non-ICE failure that causes a `FatalError` panic, from `tests/ui/recursion_limit/issue-105700.rs`:
```
#![recursion_limit="4"]
#![invalid_attribute]
#![invalid_attribute]
#![invalid_attribute]
#![invalid_attribute]
#![invalid_attribute]
//~^ERROR recursion limit reached while expanding
fn main() {{}}
```
r? ``@spastorino``
unstable-book: Separate testing and production sanitizers
This is a redo of [this PR](https://github.com/rust-lang/rust/pull/108942). Left the commit as before (except for reflowing to 80-width), since it already got approved.
Change leak check and suspicious auto trait lint warning messages
The leak check lint message "this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!" is misleading as some cases may not be phased out and could end being accepted. This is under discussion still.
The suspicious auto trait lint the change in behavior already happened, so the new message is probably more accurate.
r? `@lcnr`
Closes#93367
pattern_analysis: Move constructor selection logic to `PlaceInfo`
This is a small refactor PR. There was a dense bit of constructor-related logic in `compute_exhaustiveness_and_usefulness`. I'm moving it out into a `PlaceInfo` method to make it easier to follow both separately. I also have plans that will complicate it further so it's good that it's somewhat encapsulated.
r? `@compiler-errors`
Reimpl meaningful test name lint MCP658
This reintroduces the tidy rule originally proposed in https://github.com/rust-lang/rust/pull/113583 that then became an MCP in https://github.com/rust-lang/compiler-team/issues/658 which eventually surfaced a quite-reasonable request for a diagnostic enhancement. I have added that to the rule. It produces output like this:
```
tidy error: file `ui/unsized/issue-115809.rs` must begin with a descriptive name, try `{reason}-issue-115809.rs`
tidy error: file `ui/unsized/issue-115203.rs` must begin with a descriptive name, try `{reason}-issue-115203.rs`
tidy error: file `ui/privacy/issue-113860-2.rs` must begin with a descriptive name, try `{reason}-issue-113860.rs`
tidy error: file `ui/privacy/issue-117997.rs` must begin with a descriptive name, try `{reason}-issue-117997.rs`
tidy error: file `ui/privacy/issue-119463.rs` must begin with a descriptive name, try `{reason}-issue-119463.rs`
tidy error: file `ui/privacy/auxiliary/issue-117997.rs` must begin with a descriptive name, try `{reason}-issue-117997.rs`
tidy error: file `ui/privacy/auxiliary/issue-119463-extern.rs` must begin with a descriptive name, try `{reason}-issue-119463.rs`
tidy error: file `ui/privacy/issue-113860-1.rs` must begin with a descriptive name, try `{reason}-issue-113860.rs`
tidy error: file `ui/privacy/issue-113860.rs` must begin with a descriptive name, try `{reason}-issue-113860.rs`
tidy error: file `ui/const-generics/generic_const_exprs/const_kind_expr/issue_114151.rs` must begin with a descriptive name, try `{reason}-issue-114151.rs`
tidy error: file `ui/did_you_mean/issue-114112.rs` must begin with a descriptive name, try `{reason}-issue-114112.rs`
tidy error: file `ui/did_you_mean/issue-105225.rs` must begin with a descriptive name, try `{reason}-issue-105225.rs`
tidy error: file `ui/did_you_mean/issue-105225-named-args.rs` must begin with a descriptive name, try `{reason}-issue-105225.rs`
```
You get the idea.
There are some tests which merely would require reordering of the name according to the rule. I could modify the diagnostic further to identify those, but doing such would make it prone to bad suggestions. I have opted to trust contributors to recognize the diagnostic is robotic, as the pattern we are linting on is easier to match if we do not speculate on what parts of the name are meaningful: sometimes a word is a reason, but sometimes it is a mere "tag", such as with a pair like:
- issue-314159265-blue.rs
- issue-314159265-red.rs
Starting them with `red-` and `blue-` means they do not sort together, despite being related, and the color names are still not very descriptive. Recognizing a good name is an open-ended task, though this pair might be:
- colored-circle-gen-blue.rs
- colored-circle-gen-red.rs
Deciding exactly *how* to solve this is not the business of tidy, only recognizing a what.
r? `@compiler-errors`
Currently many diagnostic modifier methods are available on both
`Diagnostic` and `DiagnosticBuilder`. This commit removes most of them
from `Diagnostic`. To minimize the diff size, it keeps them within
`diagnostic.rs` but changes the surrounding `impl Diagnostic` block to
`impl DiagnosticBuilder`. (I intend to move things around later, to give
a more sensible code layout.)
`Diagnostic` keeps a few methods that it still needs, like `sub`,
`arg`, and `replace_args`.
The `forward!` macro, which defined two additional methods per call
(e.g. `note` and `with_note`), is replaced by the `with_fn!` macro,
which defines one additional method per call (e.g. `with_note`). It's
now also only used when necessary -- not all modifier methods currently
need a `with_*` form. (New ones can be easily added as necessary.)
All this also requires changing `trait AddToDiagnostic` so its methods
take `DiagnosticBuilder` instead of `Diagnostic`, which leads to many
mechanical changes. `SubdiagnosticMessageOp` gains a type parameter `G`.
There are three subdiagnostics -- `DelayedAtWithoutNewline`,
`DelayedAtWithNewline`, and `InvalidFlushedDelayedDiagnosticLevel` --
that are created within the diagnostics machinery and appended to
external diagnostics. These are handled at the `Diagnostic` level, which
means it's now hard to construct them via `derive(Diagnostic)`, so
instead we construct them by hand. This has no effect on what they look
like when printed.
There are lots of new `allow` markers for `untranslatable_diagnostics`
and `diagnostics_outside_of_impl`. This is because
`#[rustc_lint_diagnostics]` annotations were present on the `Diagnostic`
modifier methods, but missing from the `DiagnosticBuilder` modifier
methods. They're now present.
