HIR ty lowering: Clean up & refactor the lowering of type-relative paths
While rebasing #126651 I realized that HIR ty lowering could benefit from some *spring cleaning* now that it's been extended to handle RTN and mGCA paths.
More seriously, similar to my merged PR #118668 which unified the handling of all *associated item constraints* (assoc ty, const (ACE) & fn (RTN)), this PR (commit 695fcf517d) partially[^1] deduplicates the resolution code for all *type-relative paths* (assoc ty, const (mGCA) & fn (RTN)).
**Why**? DRY'ing that part of the code means PR #126651 will automatically support RTN paths like `Ty::AssocTy::assoc_fn(..)` and it also implies shared diagnostic code and thus better diagnostics for RTN.
---
The other commits represent cleanups, renamings, moves. More notably, I've renamed path lowering methods to be a lot more descriptive, so ones lowering `QPath(Resolved)` paths now have `_resolved_` in their name and ones lowering `QPath(TypeRelative)` paths now have `_type_relative_` in their name. This should make it stupidly obvious what their purpose is.
---
Best reviewed commit by commit. The changes are close to trivial but the diff might make it look hairier.
r? compiler-errors
[^1]: Sadly, I couldn't unify as much compared to the other PR without introducing unnecessary `unreachable!()`s or rendering the code otherwise illegible with flags and micro helper traits.
handle paren in macro expand for let-init-else expr
Fixes#131655
This PR modifies the codegen logic of the macro expansion within `let-init-else` expression:
- Before: The expression `let xxx = (mac! {}) else {}` expands to `let xxx = (expanded_ast) else {}`.
- After: The same expression expands to `let xxx = expanded_ast else {}`.
An alternative solution to this issue could involve handling the source code directly when encountering unused parentheses in `let-init-else` expressions. However, this approach might be more cumbersome due to the absence of the necessary data structure.
r? `@petrochenkov`
Check bare function idents for non snake-case name
This PR adds the check required to lint on bare function idents for non snake-case name.
Reported at #140089.
cc `@theemathas`
Rollup of 7 pull requests
Successful merges:
- #140056 (Fix a wrong error message in 2024 edition)
- #140220 (Fix detection of main function if there are expressions around it)
- #140249 (Remove `weak` alias terminology)
- #140316 (Introduce `BoxMarker` to improve pretty-printing correctness)
- #140347 (ci: clean more disk space in codebuild)
- #140349 (ci: use aws codebuild for the `dist-x86_64-linux` job)
- #140379 (rustc-dev-guide subtree update)
r? `@ghost`
`@rustbot` modify labels: rollup
Implement a lint for implicit autoref of raw pointer dereference - take 2
*[t-lang nomination comment](https://github.com/rust-lang/rust/pull/123239#issuecomment-2727551097)*
This PR aims at implementing a lint for implicit autoref of raw pointer dereference, it is based on #103735 with suggestion and improvements from https://github.com/rust-lang/rust/pull/103735#issuecomment-1370420305.
The goal is to catch cases like this, where the user probably doesn't realise it just created a reference.
```rust
pub struct Test {
data: [u8],
}
pub fn test_len(t: *const Test) -> usize {
unsafe { (*t).data.len() } // this calls <[T]>::len(&self)
}
```
Since #103735 already went 2 times through T-lang, where they T-lang ended-up asking for a more restricted version (which is what this PR does), I would prefer this PR to be reviewed first before re-nominating it for T-lang.
----
Compared to the PR it is as based on, this PR adds 3 restrictions on the outer most expression, which must either be:
1. A deref followed by any non-deref place projection (that intermediate deref will typically be auto-inserted)
2. A method call annotated with `#[rustc_no_implicit_refs]`.
3. A deref followed by a `addr_of!` or `addr_of_mut!`. See bottom of post for details.
There are several points that are not 100% clear to me when implementing the modifications:
- ~~"4. Any number of automatically inserted deref/derefmut calls." I as never able to trigger this. Am I missing something?~~ Fixed
- Are "index" and "field" enough?
----
cc `@JakobDegen` `@WaffleLapkin`
r? `@RalfJung`
try-job: dist-various-1
try-job: dist-various-2
Add `#[repr(u128)]`/`#[repr(i128)]` enums to `improper_ctypes_definitions`
This makes them warn whenever a plain `u128`/`i128` would. If the lang team decides to merge #137306 then this can be reverted.
Tracking issue: #56071
Suggest {to,from}_ne_bytes for transmutations between arrays and integers, etc
implements #136067
Rust has helper methods for many kinds of safe transmutes, for example integer<->bytes. This is a lint against using transmute for these cases.
```rs
fn bytes_at_home(x: [u8; 4]) -> u32 {
transmute(x)
}
// other examples
transmute::<[u8; 2], u16>();
transmute::<[u8; 8], f64>();
transmute::<u32, [u8; 4]>();
transmute::<char, u32>();
transmute::<u32, char>();
```
It would be handy to suggest `u32::from_ne_bytes(x)`.
This is implemented for `[u8; _]` -> `{float int}`
This also implements the cases:
`fXX` <-> `uXX` = `{from_bits, to_bits}`
`uXX` -> `iXX` via `cast_unsigned` and `cast_signed`
{`char` -> `u32`, `bool` -> `n8`} via `from`
`u32` -> `char` via `from_u32_unchecked` (note: notes `from_u32().unwrap()`) (contested)
`u8` -> `bool` via `==` (debatable)
---
try-job: aarch64-gnu
try-job: test-various
Clean UI tests 4 of n
Cleaned up some tests that have `issue` in the title. I kept the commits to be one per "`issue`" cleanup/rename to make it easier to check. I can rebase to one commit once the changes are approved.
Related Issues:
#73494#133895
r? jieyouxu
Introduce and use specialized `//@ ignore-auxiliary` for test support files instead of using `//@ ignore-test`
### Summary
Add a semantically meaningful directive for ignoring test *auxiliary* files. This is for auxiliary files that *participate* in actual tests but should not be built by `compiletest` (i.e. these files are involved through `mod xxx;` or `include!()` or `#[path = "xxx"]`, etc.).
### Motivation
A specialized directive like `//@ ignore-auxiliary` makes it way easier to audit disabled tests via `//@ ignore-test`.
- These support files cannot use the canonical `auxiliary/` dir because they participate in module resolution or are included, or their relative paths can be important for test intention otherwise.
Follow-up to:
- #139705
- #139783
- #139740
See also discussions in:
- [#t-compiler > Directive name for non-test aux files?](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Directive.20name.20for.20non-test.20aux.20files.3F/with/512773817)
- [#t-compiler > Handling disabled `//@ ignore-test` tests](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Handling.20disabled.20.60.2F.2F.40.20ignore-test.60.20tests/with/512005974)
- [#t-compiler/meetings > [steering] 2025-04-11 Dealing with disabled tests](https://rust-lang.zulipchat.com/#narrow/channel/238009-t-compiler.2Fmeetings/topic/.5Bsteering.5D.202025-04-11.20Dealing.20with.20disabled.20tests/with/511717981)
### Remarks on remaining unconditionally disabled tests under `tests/`
After this PR, against commit 79a272c640, only **14** remaining test files are disabled through `//@ ignore-test`:
<details>
<summary>Remaining `//@ ignore-test` files under `tests/`</summary>
```
tests/debuginfo/drop-locations.rs
4://@ ignore-test (broken, see #128971)
tests/rustdoc/macro-document-private-duplicate.rs
1://@ ignore-test (fails spuriously, see issue #89228)
tests/rustdoc/inline_cross/assoc-const-equality.rs
3://@ ignore-test (FIXME: #125092)
tests/ui/match/issue-27021.rs
7://@ ignore-test (#54987)
tests/ui/match/issue-26996.rs
7://@ ignore-test (#54987)
tests/ui/issues/issue-49298.rs
9://@ ignore-test (#54987)
tests/ui/issues/issue-59756.rs
2://@ ignore-test (rustfix needs multiple suggestions)
tests/ui/precondition-checks/write.rs
5://@ ignore-test (unimplemented)
tests/ui/precondition-checks/read.rs
5://@ ignore-test (unimplemented)
tests/ui/precondition-checks/write_bytes.rs
5://@ ignore-test (unimplemented)
tests/ui/explicit-tail-calls/drop-order.rs
2://@ ignore-test: tail calls are not implemented in rustc_codegen_ssa yet, so this causes 🧊
tests/ui/panics/panic-short-backtrace-windows-x86_64.rs
3://@ ignore-test (#92000)
tests/ui/json/json-bom-plus-crlf-multifile-aux.rs
3://@ ignore-test Not a test. Used by other tests
tests/ui/traits/next-solver/object-soundness-requires-generalization.rs
2://@ ignore-test (see #114196)
```
</details>
Of these, most are either **unimplemented**, or **spurious**, or **known-broken**. The outstanding one is `tests/ui/json/json-bom-plus-crlf-multifile-aux.rs` which I did not want to touch in *this* PR -- that aux file has load-bearing BOM and carriage returns and byte offset matters. I think those test files that require special encoding / BOM probably are better off as `run-make` tests. See #139968 for that aux file.
### Review advice
- Best reviewed commit-by-commit.
- The directive name diverged from the most voted `//@ auxiliary` because I think that's easy to confuse with `//@ aux-{crate,dir}`.
r? compiler
Ignore zero-sized types in wasm future-compat warning
This commit fixes a false positive of the warning triggered for #138762 and the fix is to codify that zero-sized types are "safe" in both the old and new ABIs.
This commit fixes a false positive of the warning triggered for #138762
and the fix is to codify that zero-sized types are "safe" in both the
old and new ABIs.
Explicitly annotate edition for `unpretty=expanded` and `unpretty=hir` tests
These emit prelude imports which means they are always edition dependent and so running them with a different `--edition` will fail.
Stabilize `cfg_boolean_literals`
Closes#131204
`@rustbot` labels +T-lang +I-lang-nominated
This will end up conflicting with the test in #138293 so whichever doesn't land first will need updating
--
# Stabilization Report
## General design
### What is the RFC for this feature and what changes have occurred to the user-facing design since the RFC was finalized?
[RFC 3695](https://github.com/rust-lang/rfcs/pull/3695), none.
### What behavior are we committing to that has been controversial? Summarize the major arguments pro/con.
None
### Are there extensions to this feature that remain unstable? How do we know that we are not accidentally committing to those?
None
## Has a call-for-testing period been conducted? If so, what feedback was received?
Yes; only positive feedback was received.
## Implementation quality
### Summarize the major parts of the implementation and provide links into the code (or to PRs)
Implemented in [#131034](https://github.com/rust-lang/rust/pull/131034).
### Summarize existing test coverage of this feature
- [Basic usage, including `#[cfg()]`, `cfg!()` and `#[cfg_attr()]`](6d71251cf9/tests/ui/cfg/true-false.rs)
- [`--cfg=true/false` on the command line being accessible via `r#true/r#false`](6d71251cf9/tests/ui/cfg/raw-true-false.rs)
- [Interaction with the unstable `#[doc(cfg(..))]` feature](https://github.com/rust-lang/rust/tree/6d71251/tests/rustdoc-ui/cfg-boolean-literal.rs)
- [Denying `--check-cfg=cfg(true/false)`](https://github.com/rust-lang/rust/tree/6d71251/tests/ui/check-cfg/invalid-arguments.rs)
- Ensuring `--cfg false` on the command line doesn't change the meaning of `cfg(false)`: `tests/ui/cfg/cmdline-false.rs`
- Ensuring both `cfg(true)` and `cfg(false)` on the same item result in it being disabled: `tests/ui/cfg/both-true-false.rs`
### What outstanding bugs in the issue tracker involve this feature? Are they stabilization-blocking?
The above mentioned issue; it should not block as it interacts with another unstable feature.
### What FIXMEs are still in the code for that feature and why is it ok to leave them there?
None
### Summarize contributors to the feature by name for recognition and assuredness that people involved in the feature agree with stabilization
- `@clubby789` (RFC)
- `@Urgau` (Implementation in rustc)
### Which tools need to be adjusted to support this feature. Has this work been done?
`rustdoc`'s unstable`#[doc(cfg(..)]` has been updated to respect it. `cargo` has been updated with a forward compatibility lint to enable supporting it in cargo once stabilized.
## Type system and execution rules
### What updates are needed to the reference/specification? (link to PRs when they exist)
A few lines to be added to the reference for configuration predicates, specified in the RFC.
UI tests: migrate remaining compile time `error-pattern`s to line annotations when possible
There's a number of cases in which `error-pattern` is still necessary even for compile time checking.
- It checks something that compiler writes directly into stderr as text, and not to the structured json output. This includes some stuff reported during compiler panics, and also diagnostics that happen very early, for example when parsing the command line.
- It checks something that exists only in the full rendered diagnostic test, but not in its structured components, for example code fragments or output of `-Ztrack-diagnostics`. (The latter can probably be converted to structured form though.)
This is continuation of https://github.com/rust-lang/rust/pull/139137.
r? `@jieyouxu`
Convert `tests/ui/lint/dead-code/self-assign.rs` to a known-bug test
I did a survey pass over `tests/`, and this test seems like the only candidate suitable for conversion into a known-bug test. (Other tests had varying degrees of other issues that known-bug would not be suitable.)
r? compiler
add `naked_functions_rustic_abi` feature gate
tracking issue: https://github.com/rust-lang/rust/issues/138997
Because the details of the rust abi are unstable, and a naked function must match its stated ABI, this feature gate keeps naked functions with a rustic abi ("Rust", "rust-cold", "rust-call" and "rust-intrinsic") unstable.
r? ````@traviscross````
Fix breakage when running compiletest with `--test-args=--edition=2015`
Compiletest has an `--edition` flag to change the default edition tests are run with. Unfortunately no test suite successfully executes when that flag is passed. If the edition is set to something greater than 2015 the breakage is expected, since the test suite currently supports only edition 2015 (Ferrous Systems will open an MCP about fixing that soonish). Surprisingly, the test suite is also broken if `--edition=2015` is passed to compiletest. This PR focuses on fixing the latter.
This PR fixes the two categories of failures happening when `--edition=2015` is passed:
* Some edition-specific tests set their edition through `//@ compile-flags` instead of `//@ edition`. Compiletest doesn't parse the compile flags, so it would see no `//@ edition` and add another `--edition` flag, leading to a rustc error.
* Compiletest would add the edition after `//@ compile-flags`, while some tests depend on flags passed to `//@ compile-flags` being the last flags in the rustc invocation.
Note that for the first category, I opted to manually go and replace all `//@ compile-flags` setting an edition with an explicit `//@ edition`. We could've changed compiletest to instead check whether an edition was set in `//@ compile-flags`, but I thought it was better to enforce a consistent way to set the edition in tests.
I also added the edition to the stamp, so that changing `--edition` results in tests being re-executed.
r? `@jieyouxu`
report call site of inlined scopes for large assignment lints
Addressed issue: #121672
Tracking issue: #83518
r? `@oli-obk`
I tried to follow your comment about what to do [here](https://github.com/rust-lang/rust/issues/121672#issuecomment-1972783675). However, I'm totally unfamiliar with the code so far (this is my first contribution touching compiler code), so I apologize in advance if I did something stupid 😅
In particular, I'm not sure I use the _correct_ source scope to look for inline data, as there is a whole `IndexVec` of them. My changes definitely did something, as can be seen by the added ui test. However, the result is not as anticipated in the issue:
```
LL | let cell = std::cell::UnsafeCell::new(data);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ value moved from here
```
instead of
```
LL | let cell = std::cell::UnsafeCell::new(data);
| ^^^^ value moved from here
```
raising my suspicion that maybe I got the wrong source scope.