Previously, we would retrieve the span from the `Body` using
the `locations` field. However, we may end up changing the
`locations` field when moving a constraint from a promoted
to a different body.
We now store the original `Span` in a dedication field, so that
changes to the `locations` do not affect the quality of our
diagnostics.
The loop is there to handle a `NoDelim` open/close token. This commit
changes `TokenCursor::inlined_next` so it never returns such a token.
This is a performance win because the conditional test in `bump()` is
removed.
If the parser needs changing in the future to handle `NoDelim` tokens,
then `inlined_next()` can easily be changed to return them.
The `DelimToken` here is `NoDelim`, which means the returned delim
tokens will just be ignored by `Parser::bump()`. This commit changes
things so the delim tokens won't be returned.
Miri provenance cleanup
Reviewing https://github.com/rust-lang/rust/pull/95826 by ``@carbotaniuman`` made me realize that we could clean things up a little here.
``@carbotaniuman`` please let me know if you're okay with landing this (it will create a lot of conflicts with your PR), or if you'd prefer incorporating the ideas from this PR into yours. I think we want to end up in a situation where the function you called `ptr_reify_alloc` returns just two things, a concrete tag and an offset. Getting an `AllocId` from a concrete tag should be infallible like now. However a concrete tag and `Tag` don't have to be the same type.
r? ``@oli-obk``
interpret: Fix writing uninit to an allocation
When calling `mark_init`, we need to also be mindful of what happens with the relocations! Specifically, when we de-init memory, we need to clear relocations in that range as well or else strange things will happen (and printing will not show the de-init, since relocations take precedence there).
Fixes https://github.com/rust-lang/miri/issues/2068.
Here's the Miri testcase that this fixes (requires `-Zmiri-disable-validation`):
```rust
use std::mem::MaybeUninit;
fn main() { unsafe {
let mut x = MaybeUninit::<i64>::uninit();
// Put in a ptr.
x.as_mut_ptr().cast::<&i32>().write_unaligned(&0);
// Overwrite parts of that pointer with 'uninit' through a Scalar.
let ptr = x.as_mut_ptr().cast::<i32>();
*ptr = MaybeUninit::uninit().assume_init();
// Reading this back should hence work fine.
let _c = *ptr;
} }
```
Previously this failed with
```
error: unsupported operation: unable to turn pointer into raw bytes
--> ../miri/uninit.rs:11:14
|
11 | let _c = *ptr;
| ^^^^ unable to turn pointer into raw bytes
|
= help: this is likely not a bug in the program; it indicates that the program performed an operation that the interpreter does not support
= note: inside `main` at ../miri/uninit.rs:11:14
```
Refactor loop into iterator; simplify negation logic.
is_dummy should return when a non-dummy is found, but instead is iterated until completion. With some inspiration from line 323 this was refactored to a single line that returns once a single counterexample is found.
asm: Add a kreg0 register class on x86 which includes k0
Previously we only exposed a kreg register class which excludes the k0
register since it can't be used in many instructions. However k0 is a
valid register and we need to have a way of marking it as clobbered for
clobber_abi.
Fixes#94977
Previously we only exposed a kreg register class which excludes the k0
register since it can't be used in many instructions. However k0 is a
valid register and we need to have a way of marking it as clobbered for
clobber_abi.
Fixes#94977
Rollup of 6 pull requests
Successful merges:
- #94493 (Improved diagnostic on failure to meet send bound on future in a foreign crate)
- #95809 (Fix typo in bootstrap.py)
- #96086 (Remove `--extern-location` and all associated code)
- #96089 (`alloc`: make `vec!` unavailable under `no_global_oom_handling`)
- #96122 (Fix an invalid error for a suggestion to add a slice in pattern-matching)
- #96142 (Stop using CRATE_DEF_INDEX outside of metadata encoding.)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Stop using CRATE_DEF_INDEX outside of metadata encoding.
`CRATE_DEF_ID` and `CrateNum::as_def_id` are almost always what we want. We should not manipulate raw `DefIndex` outside of metadata encoding.
Remove `--extern-location` and all associated code
`--extern-location` was an experiment to investigate the best way to
generate useful diagnostics for unused dependency warnings by enabling a
build system to identify the corresponding build config.
While I did successfully use this, I've since been convinced the
alternative `--json unused-externs` mechanism is the way to go, and
there's no point in having two mechanisms with basically the same
functionality.
This effectively reverts https://github.com/rust-lang/rust/pull/72603
Improved diagnostic on failure to meet send bound on future in a foreign crate
Provide a better diagnostic on failure to meet send bound on futures in a foreign crate.
fixes#78543
This will facilitate the change in the next commit.
`boolean` arguments aren't great, but the function is only used in three
places within this one file.
In particular, avoid wrapping a token within `TokenTree::Token` and then
immediately matching it and returning the token within. Just return the
token immediately.
show suggestion to replace generic bounds with associated types in more cases
Moves the hint to replace generic parameters with associated type bounds from the "not all associated type bounds are specified"(`E0191`) to "to many generic type parameters provided"(`E0107`).
Since `E0191` is only emitted in places where all associated types must be specified (when creating `dyn` types), the suggesting is currently not shown for other generic type uses (such as in generic type bounds). With this change the suggesting is always emitted when the number of excess generic parameters matches the number of unbound associated types.
Main motivation for the change was a lack of useful suggesting when doing
```rust
fn foo<I: Iterator<usize>>(i: I) {}
```
Report undeclared lifetimes during late resolution.
First step in https://github.com/rust-lang/rust/pull/91557
We reuse the rib design of the current resolution framework. Specific `LifetimeRib` and `LifetimeRibKind` types are introduced. The most important variant is `LifetimeRibKind::Generics`, which happens each time we encounter something which may introduce generic lifetime parameters. It can be an item or a `for<...>` binder. The `LifetimeBinderKind` specifies how this rib behaves with respect to in-band lifetimes.
r? `@petrochenkov`
Remove last vestiges of skippng ident span hashing
This removes a comment that no longer applies, and properly hashes
the full ident for path segments.
Refactor HIR item-like traversal (part 1)
Issue #95004
- Create hir_crate_items query which traverses tcx.hir_crate(()).owners to return a hir::ModuleItems
- use tcx.hir_crate_items in tcx.hir().items() to return an iterator of hir::ItemId
- use tcx.hir_crate_items to introduce a tcx.hir().par_items(impl Fn(hir::ItemId)) to traverse all items in parallel;
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
cc `@cjgillot`
Strict provenance lint diagnostics improvements
Use `multipart_suggestion` instead of `span_suggestion` and getting a snippet for the expression. Also don't suggest unnecessary parenthesis in `lossy_provenance_casts`.
cc ``@estebank``
``@rustbot`` label A-diagnostics
rustc_metadata: Do not encode unnecessary module children
This should remove the syntax context shift and the special case for `ExternCrate` in decoder in https://github.com/rust-lang/rust/pull/95880.
This PR also shifts some work from decoding to encoding, which is typically useful for performance (but probably not much in this case).
r? `@cjgillot`
Include Refs in Valtree Creation
This adds references to `const_to_valtree`, which isn't used in the compiler yet, but after the previous changes we made to the thir and mir representations and this change we should be able to finally introduce them in the next PR.
I wasn't able to properly test this code, except indirectly by including a call of `const_to_valtree` in the code that currently creates constants (`turn_into_const_value`).
r? `@lcnr`
cc `@oli-obk` `@RalfJung`
Parse inner attributes on inline const block
According to https://github.com/rust-lang/rust/pull/84414#issuecomment-826150936, inner attributes are intended to be supported *"in all containers for statements (or some subset of statements)"*.
This PR adds inner attribute parsing and pretty-printing for inline const blocks (https://github.com/rust-lang/rust/issues/76001), which contain statements just like an unsafe block or a loop body.
```rust
let _ = const {
#![allow(...)]
let x = ();
x
};
```
resolve: Create dummy bindings for all unresolved imports
Apparently such bindings weren't previously created for all unresolved imports, causing issues like https://github.com/rust-lang/rust/issues/95879.
In this PR I'm trying to create such dummy bindings in a more centralized way by calling `import_dummy_binding` once for all imports in `finalize_imports`.
Fixes https://github.com/rust-lang/rust/issues/95879.
Allow self-profiler to only record potentially costly arguments when argument recording is turned on
As discussed [on zulip](https://rust-lang.zulipchat.com/#narrow/stream/247081-t-compiler.2Fperformance/topic/Identifying.20proc-macro.20slowdowns/near/277304909) with `@wesleywiser,` I'd like to record proc-macro expansions in the self-profiler, with some detailed data (per-expansion spans for example, to follow #95473).
At the same time, I'd also like to avoid doing expensive things when tracking a generic activity's arguments, if they were not specifically opted into the event filter mask, to allow the self-profiler to be used in hotter contexts.
This PR tries to offer:
- a way to ensure a closure to record arguments will only be called in that situation, so that potentially costly arguments can still be recorded when needed. With the additional requirement that, if possible, it would offer a way to record non-owned data without adding many `generic_activity_with_arg_{...}`-style methods. This lead to the `generic_activity_with_arg_recorder` single entry-point, and the closure parameter would offer the new methods, able to be executed in a context where costly argument could be created without disturbing the profiled piece of code.
- some facilities/patterns allowing to record more rustc specific data in this situation, without making `rustc_data_structures` where the self-profiler is defined, depend on other rustc crates (causing circular dependencies): in particular, spans. They are quite tricky to turn into strings (if the default `Debug` impl output does not match the context one needs them for), and since I'd also like to avoid the allocation there when arg recording is turned off today, that has turned into another flexibility requirement for the API in this PR (separating the span-specific recording into an extension trait). **edit**: I've removed this from the PR so that it's easier to review, and opened https://github.com/rust-lang/rust/pull/95739.
- allow for extensibility in the future: other ways to record arguments, or additional data attached to them could be added in the future (e.g. recording the argument's name as well as its data).
Some areas where I'd love feedback:
- the API and names: the `EventArgRecorder` and its method for example. As well as the verbosity that comes from the increased flexibility.
- if I should convert the existing `generic_activity_with_arg{s}` to just forward to `generic_activity_with_arg_recorder` + `recorder.record_arg` (or remove them altogether ? Probably not): I've used the new API in the simple case I could find of allocating for an arg that may not be recorded, and the rest don't seem costly.
- [x] whether this API should panic if no arguments were recorded by the user-provided closure (like this PR currently does: it seems like an error to use an API dedicated to record arguments but not call the methods to then do so) or if this should just record a generic activity without arguments ?
- whether the `record_arg` function should be `#[inline(always)]`, like the `generic_activity_*` functions ?
As mentioned, r? `@wesleywiser` following our recent discussion.
Adding diagnostic data on generators to the crate metadata and using it to provide
a better diagnostic on failure to meet send bound on futures originated from a foreign crate
Rollup of 9 pull requests
Successful merges:
- #93969 (Only add codegen backend to dep info if -Zbinary-dep-depinfo is used)
- #94605 (Add missing links in platform support docs)
- #95372 (make unaligned_references lint deny-by-default)
- #95859 (Improve diagnostics for unterminated nested block comment)
- #95961 (implement SIMD gather/scatter via vector getelementptr)
- #96004 (Consider lifetimes when comparing types for equality in MIR validator)
- #96050 (Remove some now-dead code that was only relevant before deaggregation.)
- #96070 ([test] Add test cases for untested functions for BTreeMap)
- #96099 (MaybeUninit array cleanup)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Better method call error messages
Rebase/continuation of #71827
~Based on #92360~
~Based on #93118~
There's a decent description in #71827 that I won't copy here (for now at least)
In addition to rebasing, I've tried to restore most of the original suggestions for invalid arguments. Unfortunately, this does make some of the errors a bit verbose. To fix this will require a bit of refactoring to some of the generalized error suggestion functions, and I just don't have the time to go into it right now.
I think this is in a state that the error messages are overall better than before without a reduction in the suggestions given.
~I've tried to split out some of the easier and self-contained changes into separate commits (mostly in #92360, but also one here). There might be more than can be done here, but again just lacking time.~
r? `@estebank` as the original reviewer of #71827
This attempts to bring better error messages to invalid method calls, by applying some heuristics to identify common mistakes.
The algorithm is inspired by Levenshtein distance and longest common sub-sequence. In essence, we treat the types of the function, and the types of the arguments you provided as two "words" and compute the edits to get from one to the other.
We then modify that algorithm to detect 4 cases:
- A function input is missing
- An extra argument was provided
- The type of an argument is straight up invalid
- Two arguments have been swapped
- A subset of the arguments have been shuffled
(We detect the last two as separate cases so that we can detect two swaps, instead of 4 parameters permuted.)
It helps to understand this argument by paying special attention to terminology: "inputs" refers to the inputs being *expected* by the function, and "arguments" refers to what has been provided at the call site.
The basic sketch of the algorithm is as follows:
- Construct a boolean grid, with a row for each argument, and a column for each input. The cell [i, j] is true if the i'th argument could satisfy the j'th input.
- If we find an argument that could satisfy no inputs, provided for an input that can't be satisfied by any other argument, we consider this an "invalid type".
- Extra arguments are those that can't satisfy any input, provided for an input that *could* be satisfied by another argument.
- Missing inputs are inputs that can't be satisfied by any argument, where the provided argument could satisfy another input
- Swapped / Permuted arguments are identified with a cycle detection algorithm.
As each issue is found, we remove the relevant inputs / arguments and check for more issues. If we find no issues, we match up any "valid" arguments, and start again.
Note that there's a lot of extra complexity:
- We try to stay efficient on the happy path, only computing the diagonal until we find a problem, and then filling in the rest of the matrix.
- Closure arguments are wrapped in a tuple and need to be unwrapped
- We need to resolve closure types after the rest, to allow the most specific type constraints
- We need to handle imported C functions that might be variadic in their inputs.
I tried to document a lot of this in comments in the code and keep the naming clear.
Remove some now-dead code that was only relevant before deaggregation.
The code was broken anyway, if the deaggregator is disabled, it would have ICEd on any non-enum Adt
r? ```@RalfJung```
implement SIMD gather/scatter via vector getelementptr
Fixes https://github.com/rust-lang/portable-simd/issues/271
However, I don't *really* know what I am doing here... Cc ``@workingjubilee`` ``@calebzulawski``
I didn't do anything for cranelift -- ``@bjorn3`` not sure if it's okay for that backend to temporarily break. I'm happy to cherry-pick a patch that adds cranelift support. :)
Improve diagnostics for unterminated nested block comment
close#95283
(This is my first time try to messing around with rust compiler and might get a lot of things wrong... 🙇 )
make unaligned_references lint deny-by-default
This lint has been warn-by-default for a year now (since https://github.com/rust-lang/rust/pull/82525), so I think it is time to crank it up a bit. Code that triggers the lint causes UB (without `unsafe`) when executed, so we really don't want people to write code like this.
Only add codegen backend to dep info if -Zbinary-dep-depinfo is used
I am currently migrating the cg_clif build system from using a binary linked to the codegen backend as rustc replacement to passing `-Zcodegen-backend` instead. Without this PR this would force cargo to rebuild the sysroot on any change to the codegen backend even if I explicitly specify that I want it to be preserved, which would make development of cg_clif a lot slower. If you still want to have changes to the codegen backend invalidate the cargo build cache you can explicitly specify `-Zbinary-dep-depinfo`.
cc ``@eddyb`` as the codegen backend was initially added to the depinfo for rust-gpu.
Implement sym operands for global_asm!
Tracking issue: #93333
This PR is pretty much a complete rewrite of `sym` operand support for inline assembly so that the same implementation can be shared by `asm!` and `global_asm!`. The main changes are:
- At the AST level, `sym` is represented as a special `InlineAsmSym` AST node containing a path instead of an `Expr`.
- At the HIR level, `sym` is split into `SymStatic` and `SymFn` depending on whether the path resolves to a static during AST lowering (defaults to `SynFn` if `get_early_res` fails).
- `SymFn` is just an `AnonConst`. It runs through typeck and we just collect the resulting type at the end. An error is emitted if the type is not a `FnDef`.
- `SymStatic` directly holds a path and the `DefId` of the `static` that it is pointing to.
- The representation at the MIR level is mostly unchanged. There is a minor change to THIR where `SymFn` is a constant instead of an expression.
- At the codegen level we need to apply the target's symbol mangling to the result of `tcx.symbol_name()` depending on the target. This is done by calling the LLVM name mangler, which handles all of the details.
- On Mach-O, all symbols have a leading underscore.
- On x86 Windows, different mangling is used for cdecl, stdcall, fastcall and vectorcall.
- No mangling is needed on other platforms.
r? `@nagisa`
cc `@eddyb`
only downgrade selection Error -> Ambiguous if type error is in predicate
That is, we don't care if there's a TypeError type in the ParamEnv.
Fixes#95408
remove find_use_placement
A more robust solution to finding where to place use suggestions was added in #94584.
The algorithm uses the AST to find the span for the suggestion so we pass this span
down to the HIR during lowering and use it instead of calling `find_use_placement`
Fixes#94941
Check var scope if it exist
Fixes#92893.
Added helper function to check the scope of a variable, if it doesn't have a scope call delay_span_bug, which avoids us trying to get a block/scope that doesn't exist.
Had to increase `ROOT_ENTRY_LIMIT` was getting tidy error
Create (unstable) 2024 edition
[On Zulip](https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/Deprecating.20macro.20scoping.20shenanigans/near/272860652), there was a small aside regarding creating the 2024 edition now as opposed to later. There was a reasonable amount of support and no stated opposition.
This change creates the 2024 edition in the compiler and creates a prelude for the 2024 edition. There is no current difference between the 2021 and 2024 editions. Cargo and other tools will need to be updated separately, as it's not in the same repository. This change permits the vast majority of work towards the next edition to proceed _now_ instead of waiting until 2024.
For sanity purposes, I've merged the "hello" UI tests into a single file with multiple revisions. Otherwise we'd end up with a file per edition, despite them being essentially identical.
````@rustbot```` label +T-lang +S-waiting-on-review
Not sure on the relevant team, to be honest.
Stabilize `derive_default_enum`
This stabilizes `#![feature(derive_default_enum)]`, as proposed in [RFC 3107](https://github.com/rust-lang/rfcs/pull/3107) and tracked in #87517. In short, it permits you to `#[derive(Default)]` on `enum`s, indicating what the default should be by placing a `#[default]` attribute on the desired variant (which must be a unit variant in the interest of forward compatibility).
```````@rustbot``````` label +S-waiting-on-review +T-lang
`--extern-location` was an experiment to investigate the best way to
generate useful diagnostics for unused dependency warnings by enabling a
build system to identify the corresponding build config.
While I did successfully use this, I've since been convinced the
alternative `--json unused-externs` mechanism is the way to go, and
there's no point in having two mechanisms with basically the same
functionality.
This effectively reverts https://github.com/rust-lang/rust/pull/72603
when checking pointee metadata, canonicalize the `Sized` check
Use `infcx.predicate_must_hold_modulo_regions` with a `Sized` obligation instead of just calling `ty.is_sized`, because the latter does not canonicalize region and type vars (and in the test case I added in this PR, there's a region var in the `ParamEnv`).
Fixes#95311
Remove `<mbe::TokenTree as Clone>`
`mbe::TokenTree` doesn't really need to implement `Clone`, and getting rid of that impl leads to some speed-ups.
r? `@petrochenkov`
errors: lazily load fallback fluent bundle
Addresses (hopefully) https://github.com/rust-lang/rust/pull/95667#issuecomment-1094794087.
Loading the fallback bundle in compilation sessions that won't go on to emit any errors unnecessarily degrades compile time performance, so lazily create the Fluent bundle when it is first required.
r? `@ghost` (just for perf initially)
fix: wrong trait import suggestion for T:
The suggestion to bound `T` had an extra `:`.
```rust
fn foo<T:>(t: T) {
t.clone();
}
```
```
error[E0599]: no method named `clone` found for type parameter `T` in the current scope
--> src/lib.rs:2:7
|
2 | t.clone();
| ^^^^^ method not found in `T`
|
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following trait defines an item `clone`, perhaps you need to restrict type parameter `T` with it:
|
1 | fn foo<T: Clone:>(t: T) {
| ~~~~~~~~
```
Fixes: #95898
Use mir constant in thir instead of ty::Const
This is blocked on https://github.com/rust-lang/rust/pull/94059 (does include its changes, the first two commits in this PR correspond to those changes) and https://github.com/rust-lang/rust/pull/93800 being reinstated (which had to be reverted). Mainly opening since `@lcnr` offered to give some feedback and maybe also for a perf-run (if necessary).
This currently contains a lot of duplication since some of the logic of `ty::Const` had to be copied to `mir::ConstantKind`, but with the introduction of valtrees a lot of that functionality will disappear from `ty::Const`.
Only the last commit contains changes that need to be reviewed here. Did leave some `FIXME` comments regarding future implementation decisions and some things that might be incorrectly implemented.
r? `@oli-obk`
Loading the fallback bundle in compilation sessions that won't go on to
emit any errors unnecessarily degrades compile time performance, so
lazily create the Fluent bundle when it is first required.
Signed-off-by: David Wood <david.wood@huawei.com>
prevent opaque types from appearing in impl headers
cc `@lqd`
opaque types are not distinguishable from their hidden type at the codegen stage. So we could either end up with cases where the hidden type doesn't implement the trait (which will thus ICE) or where the hidden type does implement the trait (so we'd be using its impl instead of the one written for the opaque type). This can even lead to unsound behaviour without unsafe code.
Fixes https://github.com/rust-lang/rust/issues/86411.
Fixes https://github.com/rust-lang/rust/issues/84660.
rebase of #87382 plus some diagnostic tweaks
Fix suggestions in case of `T:` bounds
This PR fixes a corner case in `suggest_constraining_type_params` that was causing incorrect suggestions.
For the following functions:
```rust
fn a<T:>(t: T) { [t, t]; }
fn b<T>(t: T) where T: { [t, t]; }
```
We previously suggested the following:
```text
...
help: consider restricting type parameter `T`
|
1 | fn a<T: Copy:>(t: T) { [t, t]; }
| ++++++
...
help: consider further restricting this bound
|
2 | fn b<T>(t: T) where T: + Copy { [t, t]; }
| ++++++
```
Note that neither `T: Copy:` not `where T: + Copy` is a correct bound.
With this commit the suggestions are correct:
```text
...
help: consider restricting type parameter `T`
|
1 | fn a<T: Copy>(t: T) { [t, t]; }
| ++++
...
help: consider further restricting this bound
|
2 | fn b<T>(t: T) where T: Copy { [t, t]; }
| ++++
```
r? `@compiler-errors`
I've tried fixing #95898 here too, but got too confused with how `suggest_traits_to_import` works and what it does 😅
Move name resolution logic to a dedicated file
The code resolution logic from an Ident is scattered between several files.
The first commits creates `rustc_resolve::probe` module to hold the different mutually recursive functions together. Just a move, no code change.
The following commits attempt to make the logic a bit more readable.
The two fields `last_import_segment` and `unusable_binding` are replaced by function parameters.
In order to manage the fallout, `maybe_` variants of the function are added, dedicated to speculative resolution.
r? `@petrochenkov`
Rollup of 4 pull requests
Successful merges:
- #95783 (rustdoc doctest: include signal number in exit status)
- #95794 (`parse_tt`: a few more tweaks)
- #95963 ([bootstrap] Grab the right FileCheck binary for dist when cross-compiling.)
- #95975 (Don't test -Cdefault-linker-libraries=yes when cross compiling.)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Skip `Lazy` for some metadata tables
Some metadata tables encode their entries indirectly, through the Lazy construct. This is useful when dealing with variable length encoding, but incurs the extra cost of one u32.
Meanwhile, some fields can be encoded in a single u8, or can use a short fixed-length encoding. This PR proposes to do so, and avoid the overhead.
`impl const Default for Box<[T]>` and `Box<str>`
The unstable `const_default_impls` (#87864) already include empty `Vec<T>` and `String`. Now we extend that concept to `Box<[T]>` and `Box<str>` as well.
This obviates a hack in `rustc_ast`'s `P::<[T]>::new`.
Instead of checking only the user provided sysroot or the default (when
no sysroot is provided), search user provided sysroot and then check
default sysroots for locale requested by the user.
Signed-off-by: David Wood <david.wood@huawei.com>
use `Span::find_ancestor_inside` to get right span in CastCheck
This is a quick fix. This bad suggestion likely lives in other places... but thought it would be useful to fix all of the CastCheck ones first.
Let me know if reviewer would prefer I add more tests for each of the diagnostics in CastCheck, or would like to do a more thorough review of other suggestions that use spans in typeck. I would also be open to further suggestions on how to better expose an API that gives us the "best" span for a diagnostic suggestion.
Fixed#95919
Fix crate_type attribute to not warn on duplicates
In #88681 I accidentally marked the `crate_type` attribute as only allowing a single attribute. However, multiple attributes are allowed (they are joined together [here](027a232755/compiler/rustc_interface/src/util.rs (L530-L542))). This fixes it to not report a warning if duplicates are found.
Closes#95902
Document the current MIR semantics that are clear from existing code
This PR adds documentation to places, operands, rvalues, statementkinds, and terminatorkinds that describes their existing semantics and requirements. In many places the semantics depend on the Rust memory model or other T-Lang decisions - when this is the case, it is just noted as such with links to UCG issues where possible. I'm hopeful that none of the documentation added here can be used to justify optimizations that depend on the memory model. The documentation for places and operands probably comes closest to running afoul of this - if people think that it cannot be merged as is, it can definitely also be taken out.
The goal here is to only document parts of MIR that seem to be decided already, or are at least depended on by existing code. That leaves quite a number of open questions - those are marked as "needs clarification." I'm not sure what to do with those in this PR - we obviously can't decide all these questions here. Should I just leave them in as is? Take them out? Keep them in but as `//` instead of `///` comments?
If this is too big to review at once, I can split this up.
r? rust-lang/mir-opt
Respect -Z verify-llvm-ir and other flags that add extra passes when combined with -C no-prepopulate-passes in the new LLVM Pass Manager.
As part of the switch to the new LLVM Pass Manager the behaviour of flags such as `-Z verify-llvm-ir` (e.g. sanitizer, instrumentation) was modified when combined with `-C no-prepopulate-passes`. With the old PM, rustc was the one manually constructing the pipeline and respected those flags but in the new pass manager, those flags are used to build a list of callbacks that get invoked at certain extension points in the pipeline. Unfortunately, `-C no-prepopulate-passes` would skip building the pipeline altogether meaning we'd never add the corresponding passes. The fix here is to just manually invoke those callbacks as needed.
Fixes#95874
Demonstrating the current vs fixed behaviour using the bug in #95864
```console
$ rustc +nightly asm-miscompile.rs --edition 2021 --emit=llvm-ir -C no-prepopulate-passes -Z verify-llvm-ir
$ echo $?
0
$ rustc +stage1 asm-miscompile.rs --edition 2021 --emit=llvm-ir -C no-prepopulate-passes -Z verify-llvm-ir
Basic Block in function '_ZN14asm_miscompile3foo28_$u7b$$u7b$closure$u7d$$u7d$17h360e2f7eee1275c5E' does not have terminator!
label %bb1
LLVM ERROR: Broken module found, compilation aborted!
```
Fix miscompilation of inline assembly with outputs in cases where we emit an invoke instead of call instruction.
We ran into this bug where rustc would segfault while trying to compile certain uses of inline assembly.
Here is a simple repro that demonstrates the issue:
```rust
#![feature(asm_unwind)]
fn main() {
let _x = String::from("string here just cause we need something with a non-trivial drop");
let foo: u64;
unsafe {
std::arch::asm!(
"mov {}, 1",
out(reg) foo,
options(may_unwind)
);
}
println!("{}", foo);
}
```
([playground link](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=7d6641e83370d2536a07234aca2498ff))
But crucially `feature(asm_unwind)` is not actually needed and this can be triggered on stable as a result of the way async functions/generators are handled in the compiler. e.g.:
```rust
extern crate futures; // 0.3.21
async fn bar() {
let foo: u64;
unsafe {
std::arch::asm!(
"mov {}, 1",
out(reg) foo,
);
}
println!("{}", foo);
}
fn main() {
futures::executor::block_on(bar());
}
```
([playground link](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=1c7781c34dd4a3e80ae4bd936a0c82fc))
An example of the incorrect LLVM generated:
```llvm
bb1: ; preds = %start
%1 = invoke i64 asm sideeffect alignstack inteldialect unwind "mov ${0:q}, 1", "=&r,~{dirflag},~{fpsr},~{flags},~{memory}"()
to label %bb2 unwind label %cleanup, !srcloc !9
store i64 %1, i64* %foo, align 8
bb2:
[...snip...]
```
The store should not be placed after the asm invoke but rather should be in the normal control flow basic block (`bb2` in this case).
[Here](https://gist.github.com/luqmana/be1af5b64d2cda5a533e3e23a7830b44) is a writeup of the investigation that lead to finding this.
[`let_chains`] Forbid `let` inside parentheses
Parenthesizes are mostly a no-op in let chains, in other words, they are mostly ignored.
```rust
let opt = Some(Some(1i32));
if (let Some(a) = opt && (let Some(b) = a)) && b == 1 {
println!("`b` is declared inside but used outside");
}
```
As seen above, such behavior can lead to confusion.
A proper fix or nested encapsulation would probably require research, time and a modified MIR graph so in this PR I simply denied any `let` inside parentheses. Non-let stuff are still allowed.
```rust
fn main() {
let fun = || true;
if let true = (true && fun()) && (true) {
println!("Allowed");
}
}
```
It is worth noting that `let ...` is not an expression and the RFC did not mention this specific situation.
cc `@matthewjasper`
Rollup of 7 pull requests
Successful merges:
- #95743 (Update binary_search example to instead redirect to partition_point)
- #95771 (Update linker-plugin-lto.md to 1.60)
- #95861 (Note that CI tests Windows 10)
- #95875 (bootstrap: show available paths help text for aliased subcommands)
- #95876 (Add a note for unsatisfied `~const Drop` bounds)
- #95907 (address fixme for diagnostic variable name)
- #95917 (thin_box test: import from std, not alloc)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Only suggest removing semicolon when expression is compatible with `impl Trait`
https://github.com/rust-lang/rust/issues/54771#issuecomment-476423690
> It still needs checking that the last statement's expr can actually conform to the trait, but the naïve behavior is there.
Only suggest removing a semicolon when the type behind the semicolon actually implements the trait in an RPIT `-> impl Trait`. Also upgrade the label that suggests removing the semicolon to a suggestion (should it be verbose?).
cc #54771
When a `macro_rules! foo { ... }` invocation is compiled the name used
is `foo`, not `macro_rules!`. This is different to all other macro
invocations, and confused me when I was inserted debugging println
statements for macro evaluation.
This commit changes it to `macro_rules` (or just `macro`), which is what
I expected. There are no externally visible changes.
Rollup of 7 pull requests
Successful merges:
- #95566 (Avoid duplication of doc comments in `std::char` constants and functions)
- #95784 (Suggest replacing `typeof(...)` with an actual type)
- #95807 (Suggest adding a local for vector to fix borrowck errors)
- #95849 (Check for git submodules in non-git source tree.)
- #95852 (Fix missing space in lossy provenance cast lint)
- #95857 (Allow multiple derefs to be splitted in deref_separator)
- #95868 (rustdoc: Reduce allocations in a `html::markdown` function)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Allow multiple derefs to be splitted in deref_separator
Previously in #95649 only a single deref within projection was supported and multiple derefs caused a bunch of issues, this PR fixes those issues.
```@oli-obk``` helped a ton again ❤️
Suggest replacing `typeof(...)` with an actual type
This PR adds suggestion to replace `typeof(...)` with an actual type of `...`, for example in case of `typeof(1)` we suggest replacing it with `i32`.
If the expression
1. Is not const (`{ let a = 1; let _: typeof(a); }`)
2. Can't be found (`let _: typeof(this_variable_does_not_exist)`)
3. Or has non-suggestable type (closure, generator, error, etc)
we don't suggest anything.
The 1 one is sad, but it's not clear how to support non-consts expressions for `typeof`.
_This PR is inspired by [this tweet]._
[this tweet]: https://twitter.com/compiler_errors/status/1511945354752638976
Make def names and HIR names consistent.
The name in the `DefKey` is interned to create the `DefId`, so it does not
require any query to access. This can be leveraged to avoid a few useless
HIR accesses for names.
~In order to achieve that, generic parameters created from universal
impl-trait are given the pretty-printed ast as a name, instead of
`{{opaque}}`.~
~Drive-by: the `TyCtxt::opt_item_name` used a dummy span for non-local
definitions. We have access to `def_ident_span`, so we use it.~
We may sometimes emit an `invoke` instead of a `call` for inline
assembly during the MIR -> LLVM IR lowering. But we failed to update
the IR builder's current basic block before writing the results to the
outputs. This would result in invalid IR because the basic block would
end in a `store` instruction, which isn't a valid terminator.
expand: Remove `ParseSess::missing_fragment_specifiers`
It was used for deduplicating some errors for legacy code which are mostly deduplicated even without that, but at cost of global mutable state, which is not a good tradeoff.
cc https://github.com/rust-lang/rust/pull/95747#issuecomment-1091619403
r? ``@nnethercote``
Left overs of #95761
These are just nits. Feel free to close this PR if all modifications are not worth merging.
* `#![feature(decl_macro)]` is not needed anymore in `rustc_expand`
* `tuple_impls` does not require `$Tuple:ident`. I guess it is there to enhance readability?
r? ```@petrochenkov```
refactor: simplify few string related interactions
Few small optimizations:
check_doc_keyword: don't alloc string for emptiness check
check_doc_alias_value: get argument as Symbol to prevent needless string convertions
check_doc_attrs: don't alloc vec, iterate over slice.
replace as_str() check with symbol check
get_single_str_from_tts: don't prealloc string
trivial string to str replace
LifetimeScopeForPath::NonElided use Vec<Symbol> instead of Vec<String>
AssertModuleSource use FxHashSet<Symbol> instead of BTreeSet<String>
CrateInfo.crate_name replace FxHashMap<CrateNum, String> with FxHashMap<CrateNum, Symbol>
It was used for deduplicating some errors for legacy code which are mostly deduplicated even without that, but at cost of global mutable state, which is not a good tradeoff.
interpret: err instead of ICE on size mismatches in to_bits_or_ptr_internal
We did this a while ago already for `to_i32()` and friends, but missed this one. That became quite annoying when I was debugging an ICE caused by `read_pointer` in a Miri shim where the code was passing an argument at the wrong type.
Having `scalar_to_ptr` be fallible is consistent with all the other `Scalar::to_*` methods being fallible. I added `unwrap` only in code outside the interpreter, which is no worse off than before now in terms of panics.
r? ````@oli-obk````
Remove explicit delimiter token trees from `Delimited`.
They were introduced by the final commit in #95159 and gave a
performance win. But since the introduction of `MatcherLoc` they are no
longer needed. This commit reverts that change, making the code a bit
simpler.
r? `@petrochenkov`
Strict provenance lints
See #95488.
This PR introduces two unstable (allow by default) lints to which lint on int2ptr and ptr2int casts, as the former is not possible in the strict provenance model and the latter can be written nicer using the `.addr()` API.
Based on an initial version of the lint by ```@Gankra``` in #95199.
Cached stable hash cleanups
r? `@nnethercote`
Add a sanity assertion in debug mode to check that the cached hashes are actually the ones we get if we compute the hash each time.
Add a new data structure that bundles all the hash-caching work to make it easier to re-use it for different interned data structures
They were introduced by the final commit in #95159 and gave a
performance win. But since the introduction of `MatcherLoc` they are no
longer needed. This commit reverts that change, making the code a bit
simpler.
Enforce well formedness for type alias impl trait's hidden type
fixes#84657
This was not an issue with return-position-impl-trait because the generic bounds of the function are the same as those of the opaque type, and the hidden type must already be well formed within the function.
With type-alias-impl-trait the hidden type could be defined in a function that has *more* lifetime bounds than the type alias. This is fine, but the hidden type must still be well formed without those additional bounds.
- Create hir_crate_items query which traverses tcx.hir_crate(()).owners to return a hir::ModuleItems
- use tcx.hir_crate_items in tcx.hir().items() to return an iterator of hir::ItemId
- add par_items(impl Fn(hir::ItemId)) to traverse all items in parallel
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
* split `fuzzy_provenance_casts` into a ptr2int and a int2ptr lint
* feature gate both lints
* update documentation to be more realistic short term
* add tests for these lints
check_doc_alias_value: get argument as Symbol to prevent needless string convertions
check_doc_attrs: don't alloc vec, iterate over slice. Vec introduced in #83149, but no perf run posted on merge
replace as_str() check with symbol check
get_single_str_from_tts: don't prealloc string
trivial string to str replace
LifetimeScopeForPath::NonElided use Vec<Symbol> instead of Vec<String>
AssertModuleSource use BTreeSet<Symbol> instead of BTreeSet<String>
CrateInfo.crate_name replace FxHashMap<CrateNum, String> with FxHashMap<CrateNum, Symbol>
This commit suggests replacing typeof(...) with an actual type of "...",
for example in case of `typeof(1)` we suggest replacing it with `i32`.
If the expression
- Is not const (`{ let a = 1; let _: typeof(a); }`)
- Can't be found (`let _: typeof(this_variable_does_not_exist)`)
- Or has non-suggestable type (closure, generator, error, etc)
we don't suggest anything.
Report opaque type mismatches directly during borrowck of the function instead of within the `type_of` query.
This allows us to only store a single hidden type per opaque type instead of having to store one per set of substitutions.
r? `@compiler-errors`
This does not affect diagnostics, because the diagnostic messages are exactly the same.
This allows profiling costly arguments to be recorded only when `-Zself-profile-events=args` is on: using a closure that takes an `EventArgRecorder` and call its `record_arg` or `record_args` methods.
Use gender neutral terms
#95508 was not executed well, but it did find a couple of legitimate issues: some uses of unnecessarily gendered language, and some typos. This PR fixes (properly) the legitimate issues it found.
Stop flagging unexpected inner attributes as outer ones in certain diagnostics
Fixes#94340.
In the issue to-be-fixed I write that the general message _an inner attribute is not permitted in this context_ should be more specific noting that the “context” is the `include` macro. This, however, cannot be achieved without touching a lot of things and passing a flag to the `parse_expr` and `parse_item` calls in `expand_include`. This seems rather hacky to me. That's why I left it as it. `Span::from_expansion` does not apply either AFAIK.
`@rustbot` label A-diagnostics T-compiler
Bump bootstrap compiler to 1.61.0 beta
This PR bumps the bootstrap compiler to the 1.61.0 beta. The first commit changes the stage0 compiler, the second commit applies the "mechanical" changes and the third and fourth commits apply changes explained in the relevant comments.
r? `@Mark-Simulacrum`
By heap allocating the argument within `NtPath`, `NtVis`, and `NtStmt`.
This slightly reduces cumulative and peak allocation amounts, most
notably on `deep-vector`.
Check that all hidden types are the same and then deduplicate them.
fixes#95538
This used to trigger a sanity check. Now we accept that there may be multiple places where a hidden type is constrained and we merge all of these at the end.
Ideally we'd merge eagerly, but that is a larger refactoring that I don't want to put into a backport
New mir-opt deref_separator
This adds a new mir-opt that split certain derefs into this form:
`let x = (*a.b).c;` to => `tmp = a.b; let x = (*tmp).c;`
Huge thanks to ``@oli-obk`` for his patient mentoring.
interp/validity: enforce Scalar::Initialized
This is a follow-up to https://github.com/rust-lang/rust/pull/94527, to also account for the new kind of `Scalar` layout inside the validity checker.
r? `@oli-obk`
enhance `ConstGoto` mir-opt by moving up `StorageDead` statements
From the `FIXME` in the implementation of `ConstGoto` miropt. We can move `StorageDead` statements up to the predecessor. This can expand the scope of application of this opt.
interp: pass TyCtxt to Machine methods that do not take InterpCx
This just seems like something you might need, so let's consistently have it.
One day we might have to add `ParamEnv` as well, though that seems less likely (and in Miri you can always use `reveal_all` anyway). It might make sense to have a type that packages `TyCtxt` and `ParamEnv`, this pairing occurs quite frequently in rustc...
r? `@oli-obk`
Currently it's called in `parse_tt` every time a match rule is invoked.
This commit moves it so it's called instead once per match rule, in
`compile_declarative_macro. This is a performance win.
The commit also moves `compute_locs` out of `TtParser`, because there's
no longer any reason for it to be in there.
Let CTFE to handle partially uninitialized unions without marking the entire value as uninitialized.
follow up to #94411
To fix https://github.com/rust-lang/rust/issues/69488 and by extension fix https://github.com/rust-lang/rust/issues/94371, we should stop treating types like `MaybeUninit<usize>` as something that the `Scalar` type in the interpreter engine can represent. So we add a new field to `abi::Primitive` that records whether the primitive is nested in a union
cc `@RalfJung`
r? `@ghost`
Use the proc-macro descr to track their individual expansions with
self-profiling events. This will help diagnose performance issues
with slow proc-macros.
Note invariance reason for FnDef types
Fixes#95272. Is it worthwhile even printing a variance explanation here? Or should I try to track down which function parameter is responsible for the invariance?
r? ``@Aaron1011`` since you wrote #89336
diagnostics: translation infrastructure
An implementation of the infrastructure required to have translatable diagnostic messages.
- Introduces a `DiagnosticMessage` type which can represent both the current non-translatable messages and identifiers for [Fluent](https://projectfluent.org/).
- Modifies current diagnostic API so that existing calls still work but `DiagnosticMessage`s can be provided too.
- Adds support for always loading a "fallback bundle" containing the English diagnostic messages, which are used when a `DiagnosticMessage::FluentIdentifier` is used in a diagnostic being emitted.
- Adds support for loading a "primary bundle" which contains the user's preferred language translation, and is used preferentially when it contains a diagnostic message being emitted. Primary bundles are loaded either from the path provided to `-Ztranslate-alternate-ftl` (for testing), or from the sysroot at `$sysroot/locale/$locale/*.ftl` given a locale with `-Ztranslate-lang` (which is parsed as a language identifier).
- Adds "diagnostic args" which enable normally-interpolated variables to be made available as variables for Fluent messages to use.
- Updates `#[derive(SessionDiagnostic)]` so that it can only be used for translatable diagnostics and update the handful of diagnostics which used the derive to be translatable.
For example, the following diagnostic...
```rust
#[derive(SessionDiagnostic)]
#[error = "E0195"]
pub struct LifetimesOrBoundsMismatchOnTrait {
#[message = "lifetime parameters or bounds on {item_kind} `{ident}` do not match the trait declaration"]
#[label = "lifetimes do not match {item_kind} in trait"]
pub span: Span,
#[label = "lifetimes in impl do not match this {item_kind} in trait"]
pub generics_span: Option<Span>,
pub item_kind: &'static str,
pub ident: Ident,
}
```
...becomes...
```rust
#[derive(SessionDiagnostic)]
#[error(code = "E0195", slug = "typeck-lifetimes-or-bounds-mismatch-on-trait")]
pub struct LifetimesOrBoundsMismatchOnTrait {
#[primary_span]
#[label]
pub span: Span,
#[label = "generics-label"]
pub generics_span: Option<Span>,
pub item_kind: &'static str,
pub ident: Ident,
}
```
```fluent
typeck-lifetimes-or-bounds-mismatch-on-trait =
lifetime parameters or bounds on {$item_kind} `{$ident}` do not match the trait declaration
.label = lifetimes do not match {$item_kind} in trait
.generics-label = lifetimes in impl do not match this {$item_kind} in trait
```
r? `@estebank`
cc `@oli-obk` `@Manishearth`
In #95555 this was moved out of `parse_tt_inner` and `nameize` into
`compute_locs`. But the next commit will be moving `compute_locs`
outwards to a place that isn't suitable for the missing fragment
identifier checking. So this reinstates the old checking.
Conditional on the parallel compiler being enabled, use a different
`IntlLangMemoizer` which supports being sent between threads in
`FluentBundle`.
Signed-off-by: David Wood <david.wood@huawei.com>
`FluentId` is the type alias that is used everywhere else so it should
be used here too so that this doesn't need updated if the alias changes.
Signed-off-by: David Wood <david.wood@huawei.com>
Add an option for enabling and disabling Fluent's directionality
isolation markers in output. Disabled by default as these can render in
some terminals and applications.
Signed-off-by: David Wood <david.wood@huawei.com>
Add some links to the Fluent documentation to
`DiagnosticMessage::FluentIdentifier` which explain what a Fluent
message and attribute are.
Signed-off-by: David Wood <david.wood@huawei.com>
Removes `expected_pluralize` parameter from diagnostic struct which is
no longer necessary as the Fluent message can determine the correct
pluralization.
Signed-off-by: David Wood <david.wood@huawei.com>
If the user requests a diagnostic locale of "en-US" then it doesn't make
sense to try and load that from the `$sysroot` because it is just the
default built-in locale.
Signed-off-by: David Wood <david.wood@huawei.com>
Extends support for generating `DiagnosticMessage::FluentIdentifier`
messages from `SessionDiagnostic` derive to `#[suggestion]`.
Signed-off-by: David Wood <david.wood@huawei.com>
Extends support for generating `DiagnosticMessage::FluentIdentifier`
messages from `SessionDiagnostic` derive to `#[label]`.
Signed-off-by: David Wood <david.wood@huawei.com>
In an effort to make it easier to port diagnostics to
`SessionDiagnostic` (for translation) and since translation slugs could
replace error codes, make error codes optional in the
`SessionDiagnostic` derive.
Signed-off-by: David Wood <david.wood@huawei.com>
A call to `set_arg` is generated for every field of a
`SessionDiagnostic` struct without attributes, but not all types support
being an argument, so `#[no_arg]` is introduced to skip these fields.
Signed-off-by: David Wood <david.wood@huawei.com>
Small commit renaming `#[message]` to `#[primary_span]` as this more
accurately reflects what it does now.
Signed-off-by: David Wood <david.wood@huawei.com>
Small commit adding backticks around types and annotations in the error
messages from the session diagnostic derive.
Signed-off-by: David Wood <david.wood@huawei.com>
Fluent diagnostics can insert directionality isolation markers around
interpolated variables indicating that there may be a shift from
right-to-left to left-to-right text (or vice-versa). These are disabled
because they are sometimes visible in the error output, but may be worth
investigating in future (for example: if type names are left-to-right
and the surrounding diagnostic messages are right-to-left, then these
might be helpful).
Signed-off-by: David Wood <david.wood@huawei.com>
Non-subdiagnostic fields (i.e. those that don't have `#[label]`
attributes or similar and are just additional context) have to be added
as arguments for Fluent messages to refer them. This commit extends the
`SessionDiagnostic` derive to do this for all fields that do not have
attributes and introduces an `IntoDiagnosticArg` trait that is
implemented on all types that can be converted to a argument for Fluent.
Signed-off-by: David Wood <david.wood@huawei.com>
Move the handling of `Span` or `(Span, Applicability)` types in
`#[suggestion]` attributes to its own function.
Signed-off-by: David Wood <david.wood@huawei.com>
Various small changes to comments, like wrapping code in backticks,
changing comments to doc comments and adding newlines.
Signed-off-by: David Wood <david.wood@huawei.com>
Extend loading of Fluent bundles so that bundles can be loaded from the
sysroot based on the language requested by the user, or using a nightly
flag.
Sysroot bundles are loaded from `$sysroot/share/locale/$locale/*.ftl`.
Signed-off-by: David Wood <david.wood@huawei.com>
This commit updates the signatures of all diagnostic functions to accept
types that can be converted into a `DiagnosticMessage`. This enables
existing diagnostic calls to continue to work as before and Fluent
identifiers to be provided. The `SessionDiagnostic` derive just
generates normal diagnostic calls, so these APIs had to be modified to
accept Fluent identifiers.
In addition, loading of the "fallback" Fluent bundle, which contains the
built-in English messages, has been implemented.
Each diagnostic now has "arguments" which correspond to variables in the
Fluent messages (necessary to render a Fluent message) but no API for
adding arguments has been added yet. Therefore, diagnostics (that do not
require interpolation) can be converted to use Fluent identifiers and
will be output as before.
`MultiSpan` contains labels, which are more complicated with the
introduction of diagnostic translation and will use types from
`rustc_errors` - however, `rustc_errors` depends on `rustc_span` so
`rustc_span` cannot use types like `DiagnosticMessage` without
dependency cycles. Introduce a new `rustc_error_messages` crate that can
contain `DiagnosticMessage` and `MultiSpan`.
Signed-off-by: David Wood <david.wood@huawei.com>
Introduce a `DiagnosticMessage` type that will enable diagnostic
messages to be simple strings or Fluent identifiers.
`DiagnosticMessage` is now used in the implementation of the standard
`DiagnosticBuilder` APIs.
Signed-off-by: David Wood <david.wood@huawei.com>
rustdoc: Fix resolution of `crate`-relative paths in doc links
Resolve `crate::foo` paths transparently to rustdoc, so their resolution no longer affects diagnostics and modules used for determining traits in scope.
The proper solution is to account for the current `module_id`/`parent_scope` in `fn resolve_crate_root`, but it's a slightly larger compiler changes. This PR moves the code closer to it, but keeps it rustdoc-specific.
Fixes https://github.com/rust-lang/rust/issues/78696
Fixes https://github.com/rust-lang/rust/issues/94924
Fix late-bound ICE in `dyn` return type suggestion
This fixes the root-cause of the attached issues -- the root problem is that we're using the return type from a signature with late-bound instead of early-bound regions. The change on line 1087 (`let Some(liberated_sig) = typeck_results.liberated_fn_sigs().get(fn_hir_id) else { return false; };`) makes sure we're grabbing the _right_ return type for this suggestion to check the `dyn` predicates with.
Fixes#91801Fixes#91803
This fix also includes some drive-by changes, specifically:
1. Don't suggest boxing when we have `-> dyn Trait` and are already returning `Box<T>` where `T: Trait` (before we always boxed the value).
2. Suggestion applies even when the return type is a type alias (e.g. `type Foo = dyn Trait`). This does cause the suggestion to expand to the aliased type, but I think it's still beneficial.
3. Split up the multipart suggestion because there's a 6-line max in the printed output...
I am open to splitting out the above changes, if we just want to fix the ICE first.
cc: ```@terrarier2111``` and #92289
Mention implementers of unsatisfied trait
When encountering an unsatisfied trait bound, if there are no other
suggestions, mention all the types that *do* implement that trait:
```
error[E0277]: the trait bound `f32: Foo` is not satisfied
--> $DIR/impl_wf.rs:22:6
|
LL | impl Baz<f32> for f32 { }
| ^^^^^^^^ the trait `Foo` is not implemented for `f32`
|
= help: the trait `Foo` is implemented for `i32`
note: required by a bound in `Baz`
--> $DIR/impl_wf.rs:18:31
|
LL | trait Baz<U: ?Sized> where U: Foo { }
| ^^^ required by this bound in `Baz`
```
```
error[E0277]: the trait bound `u32: Foo` is not satisfied
--> $DIR/associated-types-path-2.rs:29:5
|
LL | f1(2u32, 4u32);
| ^^ the trait `Foo` is not implemented for `u32`
|
= help: the trait `Foo` is implemented for `i32`
note: required by a bound in `f1`
--> $DIR/associated-types-path-2.rs:13:14
|
LL | pub fn f1<T: Foo>(a: T, x: T::A) {}
| ^^^ required by this bound in `f1`
```
Suggest dereferencing in more cases.
Fix#87437, fix#90970.
When encountering an unsatisfied trait bound, if there are no other
suggestions, mention all the types that *do* implement that trait:
```
error[E0277]: the trait bound `f32: Foo` is not satisfied
--> $DIR/impl_wf.rs:22:6
|
LL | impl Baz<f32> for f32 { }
| ^^^^^^^^ the trait `Foo` is not implemented for `f32`
|
= help: the following other types implement trait `Foo`:
Option<T>
i32
str
note: required by a bound in `Baz`
--> $DIR/impl_wf.rs:18:31
|
LL | trait Baz<U: ?Sized> where U: Foo { }
| ^^^ required by this bound in `Baz`
```
Mention implementers of traits in `ImplObligation`s.
Do not mention other `impl`s for closures, ranges and `?`.
Suggest borrowing when trying to coerce unsized type into `dyn Trait`
A helpful error in response to #95598, since we can't coerce e.g. `&str` into `&dyn Display`, but we can coerce `&&str` into `&dyn Display` :)
Not sure if the suggestion message needs some help. Let me know, and I can refine this PR.
Reduce unnecessary escaping in proc_macro::Literal::character/string
I noticed that https://doc.rust-lang.org/proc_macro/struct.Literal.html#method.character is producing unreadable literals that make macro-expanded code unnecessarily hard to read. Since the proc macro server was using `escape_unicode()`, every char is escaped using `\u{…}` regardless of whether there is any need to do so. For example `Literal::character('=')` would previously produce `'\u{3d}'` which unnecessarily obscures the meaning when reading the macro-expanded code.
I've changed Literal::string also in this PR because `str`'s `Debug` impl is also smarter than just calling `escape_debug` on every char. For example `Literal::string("ferris's")` would previously produce `"ferris\'s"` but will now produce `"ferris's"`.
A new matcher representation for use in `parse_tt`
By transforming the matcher into a different form, `parse_tt` can run faster and be easier to understand.
r? `@petrochenkov`
Improve method name suggestions
Attempts to improve method name suggestions when a matching method name
is not found. The approach taken is use the Levenshtein distance and
account for substrings having a high distance but can sometimes be very
close to the intended method (eg. empty vs is_empty).
resolves#94747
`parse_tt` currently traverses a `&[TokenTree]` to do matching. But this
is a bad representation for the traversal.
- `TokenTree` is nested, and there's a bunch of expensive and fiddly
state required to handle entering and exiting nested submatchers.
- There are three positions (sequence separators, sequence Kleene ops,
and end of the matcher) that are represented by an index that exceeds
the end of the `&[TokenTree]`, which is clumsy and error-prone.
This commit introduces a new representation called `MatcherLoc` that is
designed specifically for matching. It fixes all the above problems,
making the code much easier to read. A `&[TokenTree]` is converted to a
`&[MatcherLoc]` before matching begins. Despite the cost of the
conversion, it's still a net performance win, because various pieces of
traversal state are computed once up-front, rather than having to be
recomputed repeatedly during the macro matching.
Some improvements worth noting.
- `parse_tt_inner` is *much* easier to read. No more having to compare
`idx` against `len` and read comments to understand what the result
means.
- The handling of `Delimited` in `parse_tt_inner` is now trivial.
- The three end-of-sequence cases in `parse_tt_inner` are now handled in
three separate match arms, and the control flow is much simpler.
- `nameize` is no longer recursive.
- There were two places that issued "missing fragment specifier" errors:
one in `parse_tt_inner()`, and one in `nameize()`. Presumably the
latter was never executed. There's now a single place issuing these
errors, in `compute_locs()`.
- The number of heap allocations done for a `check full` build of
`async-std-1.10.0` (an extreme example of heavy macro use) drops from
11.8M to 2.6M, and most of these occur outside of macro matching.
- The size of `MatcherPos` drops from 64 bytes to 16 bytes. Small enough
that it no longer needs boxing, which partly accounts for the
reduction in allocations.
- The rest of the drop in allocations is due to the removal of
`MatcherKind`, because we no longer need to record anything for the
parent matcher when entering a submatcher.
- Overall it reduces code size by 45 lines.
Do not use `ParamEnv::and` when building a cache key from a param-env and trait eval candidate
Do not use `ParamEnv::and` to cache a param-env with a selection/evaluation candidate.
This is because if the param-env is `RevealAll` mode, and the candidate looks global (i.e. it has erased regions, which can show up when we normalize a projection type under a binder<sup>1</sup>), then when we use `ParamEnv::and` to pair the candidate and the param-env for use as a cache key, we will throw away the param-env's caller bounds, and we'll end up caching a candidate that we inferred from the param-env with a empty param-env, which may cause cache-hit later when we have an empty param-env, and possibly mess with normalization like we see in the referenced issue during codegen.
Not sure how to trigger this with a more structured test, but changing `check-pass` to `build-pass` triggers the case that https://github.com/rust-lang/rust/issues/94903 detected.
<sup>1.</sup> That is, we will replace the late-bound region with a placeholder, which gets canonicalized and turned into an infererence variable, which gets erased during region freshening right before we cache the result. Sorry, it's quite a few steps.
Fixes#94903
r? `@Aaron1011` (or reassign as you see fit)
Don't emit non-asm contents error for naked function composed of errors
## Motivation
For naked functions an error is emitted when they are composed of anything other than a single asm!() block. However, this error triggers in a couple situations in which it adds no additional information or is actively misleading.
One example is if you do have an asm!() block but simply one with a syntax error:
```rust
#[naked]
unsafe extern "C" fn compiler_errors() {
asm!(invalid_syntax)
}
```
This results in two errors, one for the syntax error itself and another telling you that you need an asm block in your function:
```rust
error[E0787]: naked functions must contain a single asm block
--> src/main.rs:6:1
|
6 | / unsafe extern "C" fn naked_compile_error() {
7 | | asm!(blah)
8 | | }
| |_^
```
This issue also comes up when [utilizing `compile_error!()` for improving your diagnostics](https://twitter.com/steveklabnik/status/1509538243020218372), such as raising a compiler error when compiling for an unsupported target.
## Implementation
The rules this PR implements are as follows:
1. If any non-erroneous non-asm statement is included, an error will still occur
2. If multiple asm statements are included, an error will still occur
3. If 0 or 1 asm statements are present, as well as any non-zero number of erroneous statements, then this error will *not* be raised as it is likely either redundant or incorrect
The rule of thumb is effectively "if an error is present and its correction could change things, don't raise an error".
Reduce the cost of loading all built-ins targets
This PR started by measuring the exact slowdown of checking of well known conditional values.
Than this PR implemented some technics to reduce the cost of loading all built-ins targets.
cf. https://github.com/rust-lang/rust/issues/82450#issuecomment-1073992323
Add debug assertions to some unsafe functions
As suggested by https://github.com/rust-lang/rust/issues/51713
~~Some similar code calls `abort()` instead of `panic!()` but aborting doesn't work in a `const fn`, and the intrinsic for doing dispatch based on whether execution is in a const is unstable.~~
This picked up some invalid uses of `get_unchecked` in the compiler, and fixes them.
I can confirm that they do in fact pick up invalid uses of `get_unchecked` in the wild, though the user experience is less-than-awesome:
```
Running unittests (target/x86_64-unknown-linux-gnu/debug/deps/rle_decode_fast-04b7918da2001b50)
running 6 tests
error: test failed, to rerun pass '--lib'
Caused by:
process didn't exit successfully: `/home/ben/rle-decode-helper/target/x86_64-unknown-linux-gnu/debug/deps/rle_decode_fast-04b7918da2001b50` (signal: 4, SIGILL: illegal instruction)
```
~~As best I can tell these changes produce a 6% regression in the runtime of `./x.py test` when `[rust] debug = true` is set.~~
Latest commit (6894d559bd) brings the additional overhead from this PR down to 0.5%, while also adding a few more assertions. I think this actually covers all the places in `core` that it is reasonable to check for safety requirements at runtime.
Thoughts?
Attempts to improve method name suggestions when a matching method name
is not found. The approach taken is use the Levenshtein distance and
account for substrings having a high distance but can sometimes be very
close to the intended method (eg. empty vs is_empty).
make memcmp return a value of c_int_width instead of i32
This is an attempt to fix#32610 and #78022, namely, that `memcmp` always returns an `i32` regardless of the platform. I'm running into some issues and was hoping I could get some help.
Here's what I've been attempting so far:
1. Build the stage0 compiler with all the changes _expect_ for the changes in `library/core/src/slice/cmp.rs` and `compiler/rustc_codegen_llvm/src/context.rs`; this is because `target_c_int_width` isn't passed through and recognized as a valid config option yet. I'm building with `./x.py build --stage 0 library/core library/proc_macro compiler/rustc`
2. Next I add in the `#[cfg(c_int_width = ...)]` params to `cmp.rs` and `context.rs` and build the stage 1 compiler by running `./x.py build --keep-stage 0 --stage 1 library/core library/proc_macro compiler/rustc`. This step now runs successfully.
3. Lastly, I try to build the test program for AVR mentioned in #78022 with `RUSTFLAGS="--emit llvm-ir" cargo build --release`, and look at the resulting llvm IR, which still shows:
```
...
%11 = call addrspace(1) i32 `@memcmp(i8*` nonnull %5, i8* nonnull %10, i16 5) #7, !dbg !1191 %.not = icmp eq i32 %11, 0, !dbg !1191
...
; Function Attrs: nounwind optsize declare i32 `@memcmp(i8*,` i8*, i16) local_unnamed_addr addrspace(1) #4
```
Any ideas what I'm missing here? Alternately, if this is totally the wrong approach I'm open to other suggestions.
cc `@Rahix`
Use DefPathHash instead of HirId to break inlining cycles.
The `DefPathHash` is stable across incremental compilation sessions, so provides a total order on `LocalDefId`. Using it instead of `HirId` ensures the MIR inliner has the same behaviour for incremental and non-incremental compilation.
A downside is that the cycle tie break is not as predictable is with `HirId`.
Suggest `i += 1` when we see `i++` or `++i`
Closes#83502 (for `i++` and `++i`; `--i` should be covered by #82987, and `i--`
is tricky to handle).
This is a continuation of #83536.
r? `@estebank`
Fix multiline attributes handling in doctests
Fixes#55713.
I needed to have access to the `unclosed_delims` field in order to check that the attribute was completely parsed and didn't have missing parts, so I created a getter for it.
r? `@notriddle`
Rollup of 4 pull requests
Successful merges:
- #95587 (Remove need for associated_type_bounds in std.)
- #95589 (Include a header in .rlink files)
- #95593 (diagnostics: add test case for bogus T:Sized suggestion)
- #95597 (Refer to u8 by absolute path in expansion of thread_local)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Include a header in .rlink files
I couldn't find the right place where to put tests. Is there some location that tests `.rlink` creation and loading?
I only found `src/test/run-make-fulldeps/separate-link/Makefile`, but I'm not sure how to check the error message in the Makefile.
Fixes: https://github.com/rust-lang/rust/issues/95297
r? `@bjorn3`
Make GATs object safe under generic_associated_types_extended feature
Based on #94869
Let's say we have
```rust
trait StreamingIterator {
type Item<'a> where Self: 'a;
}
```
And `dyn for<'a> StreamingIterator<Item<'a> = &'a i32>`.
If we ask `(dyn for<'a> StreamingIterator<Item<'a> = &'a i32>): StreamingIterator`, then we have to prove that `for<'x> (&'x i32): Sized`. So, we generate *new* bound vars to subst for the GAT generics.
Importantly, this doesn't fully verify that these are usable and sound.
r? `@nikomatsakis`
Add error message suggestion for missing noreturn in naked function
I had to google the syntax for inline asm's `noreturn` option when I got this error earlier today, so I figured I'd save others the trouble and add the syntax/fix as a suggestion in the error.
Handle rustc_const_stable attribute in library feature collector
The library feature collector in [compiler/rustc_passes/src/lib_features.rs](551b4fa395/compiler/rustc_passes/src/lib_features.rs) has only been looking at `#[stable(…)]`, `#[unstable(…)]`, and `#[rustc_const_unstable(…)]` attributes, while ignoring `#[rustc_const_stable(…)]`. The consequences of this were:
- When any const feature got stabilized (changing one or more `rustc_const_unstable` to `rustc_const_stable`), users who had previously enabled that unstable feature using `#![feature(…)]` would get told "unknown feature", rather than rustc's nicer "the feature … has been stable since … and no longer requires an attribute to enable".
This can be seen in the way that https://github.com/rust-lang/rust/pull/93957#issuecomment-1079794660 failed after rebase:
```console
error[E0635]: unknown feature `const_ptr_offset`
--> $DIR/offset_from_ub.rs:1:35
|
LL | #![feature(const_ptr_offset_from, const_ptr_offset)]
| ^^^^^^^^^^^^^^^^
```
- We weren't enforcing that a particular feature is either stable everywhere or unstable everywhere, and that a feature that has been stabilized has the same stabilization version everywhere, both of which we enforce for the other stability attributes.
This PR updates the library feature collector to handle `rustc_const_stable`, and fixes places in the standard library and test suite where `rustc_const_stable` was being used in a way that does not meet the rules for a stability attribute.
Rollup of 6 pull requests
Successful merges:
- #95032 (Clean up, categorize and sort unstable features in std.)
- #95260 (Better suggestions for `Fn`-family trait selection errors)
- #95293 (suggest wrapping single-expr blocks in square brackets)
- #95344 (Make `impl Debug for rustdoc::clean::Item` easier to read)
- #95388 (interpret: make isize::MAX the limit for dynamic value sizes)
- #95530 (rustdoc: do not show primitives and keywords as private)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
interpret: make isize::MAX the limit for dynamic value sizes
We are currently enforcing `data_layout.obj_size_bound()` as the maximal dynamic size of a Rust value (including for `size_of_val_raw`), but that does not match the docs.
In particular, Miri currently falsely says that this code has UB:
```rust
#![feature(layout_for_ptr)]
fn main() {
let size = isize::MAX as usize;
// Creating a raw slice of size isize::MAX and asking for its size is okay.
let s = std::ptr::slice_from_raw_parts(1usize as *const u8, size);
assert_eq!(size, unsafe { std::mem::size_of_val_raw(s) });
}
```
Better suggestions for `Fn`-family trait selection errors
1. Suppress suggestions to add `std::ops::Fn{,Mut,Once}` bounds when a type already implements `Fn{,Mut,Once}`
2. Add a note that points out that a type does in fact implement `Fn{,Mut,Once}`, but the arguments vary (either by number or by actual arguments)
3. Add a note that points out that a type does in fact implement `Fn{,Mut,Once}`, but not the right one (e.g. implements `FnMut`, but `Fn` is required).
Fixes#95147
A more robust solution to finding where to place use suggestions was added.
The algorithm uses the AST to find the span for the suggestion so we pass this span
down to the HIR during lowering and use it.
Signed-off-by: Miguel Guarniz <mi9uel9@gmail.com>
Specialize infinite-type "insert some indirection" suggestion for Option
Suggest `Option<Box<_>>` instead of `Box<Option<_>>` for infinitely-recursive members of a struct.
Not sure if I can get the span of the generic subty of the Option so I can make this a `+++`-style suggestion. The current output is a tiny bit less fancy looking than the original suggestion.
Should I limit the specialization to just `Option<Box<TheOuterStruct>>`? Because right now it applies to all `Option` members in the struct that are returned by `Representability::SelfRecursive`.
Fixes#91402
r? `@estebank`
(since you wrote the original suggestion and are definitely most familiar with it!)
Make lowering pull-based
~Based on https://github.com/rust-lang/rust/pull/90451~
Part of https://github.com/rust-lang/rust/pull/88186
The current lowering code visits all the item-likes in the AST in order, and lowers them one by one.
This PR changes it to index the AST and then proceed to lowering on-demand. This is closer to the logic of query-based lowering.
allow large Size again
This basically reverts most of https://github.com/rust-lang/rust/pull/80042, and instead does the panic in `bits()` with a `#[cold]` function to make sure it does not get inlined.
https://github.com/rust-lang/rust/pull/80042 added a comment about an invariant ("The top 3 bits are ALWAYS zero") that is not actually enforced, and if it were enforced that would be a problem for https://github.com/rust-lang/rust/pull/95388. So I think we should not have that invariant, and I adjusted the code accordingly.
r? `@oli-obk` Cc `@sivadeilra`
It's only used in one place, and there we clone and then make a bunch of
modifications. It's clearer if we duplicate more explicitly, and there's
a symmetry now between `sequence()` and `empty_sequence()`.
`parse_tt` needs a way to get from within submatchers make to the
enclosing submatchers. Currently it has two distinct mechanisms for
this:
- `Delimited` submatchers use `MatcherPos::stack` to record stuff about
the parent (and further back ancestors).
- `Sequence` submatchers use `MatcherPosSequence::parent` to point to
the parent matcher position.
Having two mechanisms is really confusing, and it took me a long time to
understand all this.
This commit eliminates `MatcherPos::stack`, and changes `Delimited`
submatchers to use the same mechanism as sequence submatchers. That
mechanism is also changed a bit: instead of storing the entire parent
`MatcherPos`, we now only store the necessary parts from the parent
`MatcherPos`.
Overall this is a small performance win, with the positives outweighing
the negatives, but it's mostly for clarity.
Spellchecking compiler comments
This PR cleans up the rest of the spelling mistakes in the compiler comments. This PR does not change any literal or code spelling issues.
Don't ICE when opaque types get their hidden type constrained again.
Contrary to popular belief, `codegen_fulfill_obligation` does not get used solely in codegen, so we cannot rely on `param_env` being set to RevealAll and thus revealing the hidden types instead of constraining them.
Fixes#89312 (for real this time)
Restore `impl Future<Output = Type>` to async blocks
I was sad when I undid some of the code I wrote in #91096 in the PR #95225, so I fixed it here to not print `[async output]`.
This PR "manually" normalizes the associated type `<[generator] as Generator>::Return` type which appears very frequently in `impl Future` types that result from async block desugaring.
Currently, we detect an exit from a `Delimited` submatcher when `idx`
exceeds the bounds of the current submatcher *and* there is a `stack`
entry.
This commit changes it to something simpler: just look for a
`CloseDelim` token.
Rollup of 6 pull requests
Successful merges:
- #93901 (Stabilize native library modifier syntax and the `whole-archive` modifier specifically)
- #94806 (Fix `cargo run tidy`)
- #94869 (Add the generic_associated_types_extended feature)
- #95011 (async: Give predictable name to binding generated from .await expressions.)
- #95251 (Reduce max hash in raw strings from u16 to u8)
- #95298 (Fix double drop of allocator in IntoIter impl of Vec)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
async: Give predictable name to binding generated from .await expressions.
This name makes it to debuginfo and allows debuggers to identify such bindings and their captured versions in suspended async fns.
This will be useful for async stack traces, as discussed in https://internals.rust-lang.org/t/async-debugging-logical-stack-traces-setting-goals-collecting-examples/15547.
I don't know if this needs some discussion by ````@rust-lang/compiler,```` e.g. about the name of the binding (`__awaitee`) or about the fact that this PR introduces a (soft) guarantee about a compiler generated name. Although, regarding the later, I think the same reasoning applies here as it does for debuginfo in general.
r? ````@tmandry````
Add the generic_associated_types_extended feature
Right now, this only ignore obligations that reference new placeholders in `poly_project_and_unify_type`. In the future, this might do other things, like allowing object-safe GATs.
**This feature is *incomplete* and quite likely unsound. This is mostly just for testing out potential future APIs using a "relaxed" set of rules until we figure out *proper* rules.**
Also drive by cleanup of adding a `ProjectAndUnifyResult` enum instead of using a `Result<Result<Option>>`.
r? `@nikomatsakis`
Remember mutability in `DefKind::Static`.
This allows to compute the `BodyOwnerKind` from `DefKind` only, and
removes a direct dependency of some MIR queries onto HIR.
As a side effect, it also simplifies metadata, since we don't need 4
flavours of `EntryKind::*Static` any more.
Yet more `parse_tt` improvements
Including lots of comment improvements, and an overhaul of how `matches` work that gives big speedups.
r? `@petrochenkov`
Contrary to popular belief, `codegen_fulfill_obligation` does not get used solely in codegen, so we cannot rely on `param_env` being set to RevealAll and thus revealing the hidden types instead of constraining them.
allow arbitrary inherent impls for builtin types in core
Part of https://github.com/rust-lang/compiler-team/issues/487. Slightly adjusted after some talks with `@m-ou-se` about the requirements of `t-libs-api`.
This adds a crate attribute `#![rustc_coherence_is_core]` which allows arbitrary impls for builtin types in core.
For other library crates impls for builtin types should be avoided if possible. We do have to allow the existing stable impls however. To prevent us from accidentally adding more of these in the future, there is a second attribute `#[rustc_allow_incoherent_impl]` which has to be added to **all impl items**. This only supports impls for builtin types but can easily be extended to additional types in a future PR.
This implementation does not check for overlaps in these impls. Perfectly checking that requires us to check the coherence of these incoherent impls in every crate, as two distinct dependencies may add overlapping methods. It should be easy enough to detect if it goes wrong and the attribute is only intended for use inside of std.
The first two commits are mostly unrelated cleanups.
Strict Provenance MVP
This patch series examines the question: how bad would it be if we adopted
an extremely strict pointer provenance model that completely banished all
int<->ptr casts.
The key insight to making this approach even *vaguely* pallatable is the
ptr.with_addr(addr) -> ptr
function, which takes a pointer and an address and creates a new pointer
with that address and the provenance of the input pointer. In this way
the "chain of custody" is completely and dynamically restored, making the
model suitable even for dynamic checkers like CHERI and Miri.
This is not a formal model, but lots of the docs discussing the model
have been updated to try to the *concept* of this design in the hopes
that it can be iterated on.
See #95228
