Add error if link_ordinal used with unsupported link kind
The `link_ordinal` attribute only has an affect if the `raw-dylib` link kind is used, so add an error if it is used with any other link kind.
Stabilize backtrace
This PR stabilizes the std::backtrace module. As of #99431, the std::Error::backtrace item has been removed, and so the rest of the backtrace feature is set to be stabilized.
Previous discussion can be found in #72981, #3156.
Stabilized API summary:
```rust
pub mod std {
pub mod backtrace {
pub struct Backtrace { }
pub enum BacktraceStatus {
Unsupported,
Disabled,
Captured,
}
impl fmt::Debug for Backtrace {}
impl Backtrace {
pub fn capture() -> Backtrace;
pub fn force_capture() -> Backtrace;
pub const fn disabled() -> Backtrace;
pub fn status(&self) -> BacktraceStatus;
}
impl fmt::Display for Backtrace {}
}
}
```
`@yaahc`
Set tainted errors bit before emitting coerce suggestions.
Fixes#100246.
#89576 basically got 99% of the way there but the match typechecking code (which calls `coerce_inner`) also needed a similar fix.
Add some high-level docs to `FnCtxt` and `ItemCtxt`
I haven't understood the difference between these before, but
``@compiler-errors`` helped me clear it up. Hopefully this will help other
people who've been confused!
r? `@compiler-errors`
Some "this expression has a field"-related fixes
Each commit does something different and is worth reviewing, but the final diff from `master..HEAD` contains the sum of the changes to the UI tests, since some commits added UI tests "regressions" which were later removed in other commits.
The only change I could see adding on top of this is suppressing `Clone::clone` from the "this expression has a field that has this method" suggestion, since it's so commonly implemented by types that it's not worthwhile suggesting in general.
Error on broken pipe but do not backtrace or ICE
Windows will report a broken pipe as a normal error which in turn `println!` will panic on. Currently this causes rustc to produce a backtrace and ICE. However, this is not a bug with rustc so a backtrace is overly verbose and ultimately unhelpful to the user.
Kind of fixes#98700. Although this is admittedly a bit of a hack because at panic time all we have is a string to inspect. On zulip it was suggested that libstd might someday provide a way to indicate a soft panic but that day isn't today.
consider unnormalized types for implied bounds
extracted, and slightly modified, from #98900
The idea here is that generally, rustc is split into things which can assume its inputs are well formed[^1], and things which have verify that themselves.
Generally most predicates should only deal with well formed inputs, e.g. a `&'a &'b (): Trait` predicate should be able to assume that `'b: 'a` holds. Normalization can loosen wf requirements (see #91068) and must therefore not be used in places which still have to check well formedness. The only such place should hopefully be `WellFormed` predicates
fixes#87748 and #98543
r? `@jackh726` cc `@rust-lang/types`
[^1]: These places may still encounter non-wf inputs and have to deal with them without causing an ICE as we may check for well formedness out of order.
Re-structure the stability checks for library features to avoid calling
`defined_lib_features` for any more crates than necessary for each of
the implications or local feature attributes that need validation.
Don't ICE while suggesting updating item path.
When an item isn't found, we may suggest an appropriate import to `use`. Along with that, we also suggest updating the path to work with the `use`. Unfortunately, if the code in question originates from a macro, the span used to indicate which part of the path needs updating may not be suitable and cause an ICE (*). Since, such code is not adjustable directly by the user without modifying the macro, just skip the suggestion in such cases.
(*) The ICE happens because the emitter want to indicate to the user what code to delete by referencing a certain span. But in this case, said span has `lo == hi == 0` which means it thinks it's a dummy span. Adding a space before the proc macro attribute is enough to stop it from ICE'ing but even then the suggestion doesn't really make any sense:
```
help: if you import `DataStore`, refer to it directly
|
1 - #[dbstruct::dbstruct]
1 + #[dbstruct::dbstruct]
```
Since suggestions are best-effort, I just gated this one on `can_be_used_for_suggestions` which catches cases like this.
Fixes#100199
Don't document impossible to call default trait items on impls
Closes#100176
This only skips documenting _default_ trait items on impls, not ones that are written inside the impl block. This is a conservative approach, since I think we should document all items written in an impl block (I guess unless hidden or whatever), but the existence of this new query I added makes this easy to extend to other rustdoc cases.
Implement `#[rustc_default_body_unstable]`
This PR implements a new stability attribute — `#[rustc_default_body_unstable]`.
`#[rustc_default_body_unstable]` controls the stability of default bodies in traits.
For example:
```rust
pub trait Trait {
#[rustc_default_body_unstable(feature = "feat", isssue = "none")]
fn item() {}
}
```
In order to implement `Trait` user needs to either
- implement `item` (even though it has a default implementation)
- enable `#![feature(feat)]`
This is useful in conjunction with [`#[rustc_must_implement_one_of]`](https://github.com/rust-lang/rust/pull/92164), we may want to relax requirements for a trait, for example allowing implementing either of `PartialEq::{eq, ne}`, but do so in a safe way — making implementation of only `PartialEq::ne` unstable.
r? `@Aaron1011`
cc `@nrc` (iirc you were interested in this wrt `read_buf`), `@danielhenrymantilla` (you were interested in the related `#[rustc_must_implement_one_of]`)
P.S. This is my first time working with stability attributes, so I'm not sure if I did everything right 😅
Add option to `mir::MutVisitor` to not invalidate CFG.
This also applies that option to some uses of the visitor. I had considered a design more similar to #100087 in which we detect if the CFG needs to be invalidated, but that is more difficult with the visitor API and so I decided against it. Another alternative to this design is to offer an API for "saving" and "restoring" CFG caches across arbitrary code. Such an API is more general, and so we may eventually want it anyway, but it seems overkill for this use case.
r? `@tmiasko`
https://reviews.llvm.org/D120026 changed atomics on thumbv6m to
use libatomic, to ensure that atomic load/store are compatible with
atomic RMW/CAS. However, Rust wants to expose only load/store
without libcalls.
https://reviews.llvm.org/D130480 added support for this behind
the +atomics-32 target feature, so enable that feature.
Implement special-cased projection error message for some common traits
Not sure what the best phrasing is, but I feel like these are more clear than the plain `<Type as Iterator>::Output == Type` messages.
If this is actually a good idea, are there any other traits this could benefit?
I haven't understood the difference between these before, but
`@compiler-errors` helped me clear it up. Hopefully this will help other
people who've been confused!
Add armv4t-none-eabi take2
This is the same as the previous PR (https://github.com/rust-lang/rust/pull/99226) but i just made a fresh branch without a merge commit in it.
---
### armv4t-none-eabi target quiz
> A tier 3 target must have a designated developer or developers (the "target maintainers") on record to be CCed when issues arise regarding the target.
That's me!
> Targets must use naming consistent with any existing targets
We're using the existing name as recognized by LLVM and GCC
> Tier 3 targets may have unusual requirements to build or use, but must not create legal issues or impose onerous legal terms for the Rust project or for Rust developers or users.
No legal issues here.
>> The target must not introduce license incompatibilities.
No license requirements here.
>> Anything added to the Rust repository must be under the standard Rust license (MIT OR Apache-2.0).
check
>> The target must not cause the Rust tools or libraries built for any other host (even when supporting cross-compilation to the target) to depend on any new dependency less permissive than the Rust licensing policy.
no new deps, we're just adding a rustc target description file for a target llvm already knows about.
>> Compiling, linking, and emitting functional binaries, libraries, or other code for the target (whether hosted on the target itself or cross-compiling from another target) must not depend on proprietary (non-FOSS) libraries.
bare-metal target, doesn't rely on any libs at all.
> Tier 3 targets should attempt to implement as much of the standard libraries as possible and appropriate
`core` only here. You could build `alloc` too, but you'd have to bring your own global allocator.
> The target must provide documentation for the Rust community explaining how to build for the target, using cross-compilation if possible.
LLVM knows how to do it, you just need the GNU Binutils linker because LLVM's linker doesn't work that far back. That's in the docs as part of this PR.
> Tier 3 targets must not impose burden on the authors of pull requests, or other developers in the community, to maintain the target.
No burdens, LLVM already knows how to do this. Further, because this is a cpu-feature variant of an existing tier3 target the `compiler-builtins` crate has already been updated as necessary to fix any missing builtin function gaps.
> Patches adding or updating tier 3 targets must not break any existing tier 2 or tier 1 target, and must not knowingly break another tier 3 target without approval of either the compiler team or the maintainers of the other tier 3 target.
check.
Use start_point instead of next_point to point to elided lifetime amp…
Using `next_point` creates a span which points inside the multibyte token, ICEing.
Fixes https://github.com/rust-lang/rust/issues/100224
Multiple duplicate assignments of the same discriminant are now reported
in the samme error. We now point out the incrementation start point for
discriminants that are not explicitly assigned that are also duplicates.
Removed old test related to E0081 that is now covered by error-codes/E0081.rs.
Also refactored parts of the `check_enum` function.
When an item isn't found, we may suggest an appropriate import to
`use`. Along with that, we also suggest updating the path to work
with the `use`. Unfortunately, if the code in question originates
from a macro, the span used to indicate which part of the path
needs updating may not be suitable and cause an ICE. Since, such
code is not adjustable directly by the user without modifying the
macro, just skip the suggestion in such cases.
Check link ordinal to make sure it is targetted for foreign function
Fix#100009, when link ordinal is not target for foreign functions, emit an error.
cc `@dpaoliello`
Avoid pointing out `return` span if it has nothing to do with type error
This code:
```rust
fn f(_: String) {}
fn main() {
let x = || {
if true {
return ();
}
f("");
};
}
```
Emits this:
```
Compiling playground v0.0.1 (/playground)
error[E0308]: mismatched types
--> src/main.rs:8:11
|
8 | f("");
| ^^- help: try using a conversion method: `.to_string()`
| |
| expected struct `String`, found `&str`
|
note: return type inferred to be `String` here
--> src/main.rs:6:20
|
6 | return ();
| ^^
```
Specifically, that note has nothing to do with the type error in question. This is because the change implemented in #84244 tries to point out the `return` span on _any_ type coercion error within a closure that happens after a `return` statement, regardless of if the error has anything to do with it.
This is really easy to trigger -- just needs a closure (or an `async`) and an early return (or any other form, e.g. `?` operator suffices) -- and super distracting in production codebases. I'm letting #84128 regress because that issue is much harder to fix correctly, and I can re-open that issue after this lands.
As a drive-by, I added a `resolve_vars_if_possible` to the coercion error logic, which leads to some error improvements. Unrelated to the issue above, though.
Rollup of 4 pull requests
Successful merges:
- #100094 (Detect type mismatch due to loop that might never iterate)
- #100132 (Use (actually) dummy place for let-else divergence)
- #100167 (Recover `require`, `include` instead of `use` in item)
- #100193 (Remove more Clean trait implementations)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Detect type mismatch due to loop that might never iterate
When loop as tail expression causes a miss match type E0308 error, recursively get the return statement and add diagnostic information on it.
Temporaries created with `MirPatch::new_temp` will be declared after
patch application. Remove manually created duplicate declarations.
Removing duplicates exposes another issue. Visitor elaborates
terminator twice and attempts to access new, but not yet available,
local declarations. Remove duplicated call to `visit_terminator`.
Enable function merging when opt is for size
It is, of course, natural to want to merge aliasing functions when
optimizing for code size, since that can eliminate several bytes.
And an exhaustive match helps make the code less brittle.
Closes#98215.
It is, of course, natural to want to merge aliasing functions when
optimizing for code size, since that can eliminate several bytes.
And an exhaustive match helps make the code less brittle.
when loop as tail expression for miss match type E0308 error, recursively get
the return statement and add diagnostic information on it
use rustc_hir::intravisit to collect the return expression
modified: compiler/rustc_typeck/src/check/coercion.rs
new file: src/test/ui/typeck/issue-98982.rs
new file: src/test/ui/typeck/issue-98982.stderr
Improve diagnostics for `const a: = expr;`
Adds a suggestion to write a type when there is a colon, but the type is not present.
I've also shrunk spans a little, so the suggestions are a little nicer.
Resolves#100146
r? `@compiler-errors`
Add test for raw-dylib with an external variable
All existing tests of link kind `raw-dylib` only validate the ability to link against functions, but it is also possible to link against variables.
This adds tests for linking against a variable using `raw-dylib` both by-name and by-ordinal.
Warn about dead tuple struct fields
Continuation of #92972. Fixes#92790.
The language team has already commented on this in https://github.com/rust-lang/rust/pull/92972#issuecomment-1021511970; I have incorporated their requests here. Specifically, there is now a new allow-by-default `unused_tuple_struct_fields` lint (name bikesheddable), and fields of unit type are ignored (https://github.com/rust-lang/rust/pull/92972#issuecomment-1021815408), so error messages look like this:
```
error: field is never read: `1`
--> $DIR/tuple-struct-field.rs:6:21
|
LL | struct Wrapper(i32, [u8; LEN], String);
| ^^^^^^^^^
|
help: change the field to unit type to suppress this warning while preserving the field numbering
|
LL | struct Wrapper(i32, (), String);
| ~~
```
r? `@joshtriplett`
Split create_def and lowering of lifetimes for opaque types and bare async fns
r? `@cjgillot`
This work is kind of half-way, but I think it could be merged anyway.
I think we should be able to remove all the vacant arms in `new_named_lifetime_with_res`, if I'm not wrong that requires visiting more nodes. We can do that as a follow up.
In follow-up PRs, besides the thing mentioned previously, I'll be trying to remove `LifetimeCaptureContext`, `captured_lifetimes` as a global data structure, global `binders_to_ignore` and all their friends :).
Also try to remap in a more general way based on def-ids.
Enable unused_parens for match arms
Fixes: https://github.com/rust-lang/rust/issues/92751
Currently I can't get the `stderr` to work with `./x.py test`, but this should fix the issue. Help would be appreciated!