Highlight clarifying information in "expected/found" error
When the expected and found types have the same textual representation, we add clarifying in parentheses. We now visually highlight it in the output.
Detect a corner case where the clarifying information would be the same for both types and skip it, as it doesn't add anything useful.

diagnostics: fix borrowck suggestions for if/while let conditionals
This code detects the case where one of the borrows is inside the let init expr while the other end is not. If that happens, we don't want to suggest adding a semicolon, because it won't work.
Fixes#133941
Tweak fn pointer suggestion span
Use a more targeted span when suggesting casting an `fn` item to an `fn` pointer.
```
error[E0308]: cannot coerce functions which must be inlined to function pointers
--> $DIR/cast.rs:10:33
|
LL | let _: fn(isize) -> usize = callee;
| ------------------ ^^^^^^ cannot coerce functions which must be inlined to function pointers
| |
| expected due to this
|
= note: expected fn pointer `fn(_) -> _`
found fn item `fn(_) -> _ {callee}`
= note: fn items are distinct from fn pointers
help: consider casting to a fn pointer
|
LL | let _: fn(isize) -> usize = callee as fn(isize) -> usize;
| +++++++++++++++++++++
```
```
error[E0308]: mismatched types
--> $DIR/fn-pointer-mismatch.rs:42:30
|
LL | let d: &fn(u32) -> u32 = foo;
| --------------- ^^^ expected `&fn(u32) -> u32`, found fn item
| |
| expected due to this
|
= note: expected reference `&fn(_) -> _`
found fn item `fn(_) -> _ {foo}`
help: consider using a reference
|
LL | let d: &fn(u32) -> u32 = &foo;
| +
```
Previously we'd point at the whole expression for replacement, instead of marking what was being added.
We could also modify the suggestions for `&(name as fn())`, but for that we require storing more accurate spans than we have now.
Rework "long type names" printing logic
Make it so more type-system types can be printed in a shortened version (like `Predicate`s).
Centralize printing the information about the "full type name path".
Make the "long type path" for the file where long types are written part of `Diag`, so that it becomes easier to keep track of it, and ensure it will always will be printed out last in the diagnostic by making its addition to the output implicit.
Tweak the shortening of types in "expected/found" labels.
Remove dead file `note.rs`.
When the expected and found types have the same textual representation, we add clarifying in parentheses. We now visually highlight it in the output.
Detect a corner case where the clarifying information would be the same for both types and skip it, as it doesn't add anything useful.
```
error: expected `{closure@...}` to return `Ret`, but it returns `Other`
```
instead of
```
error: expected `{closure@...}` to be a closure that returns `Ret`, but it returns `Other`
```
Use a more targeted span when suggesting casting an `fn` item to an `fn` pointer.
```
error[E0308]: cannot coerce functions which must be inlined to function pointers
--> $DIR/cast.rs:10:33
|
LL | let _: fn(isize) -> usize = callee;
| ------------------ ^^^^^^ cannot coerce functions which must be inlined to function pointers
| |
| expected due to this
|
= note: expected fn pointer `fn(_) -> _`
found fn item `fn(_) -> _ {callee}`
= note: fn items are distinct from fn pointers
help: consider casting to a fn pointer
|
LL | let _: fn(isize) -> usize = callee as fn(isize) -> usize;
| +++++++++++++++++++++
```
```
error[E0308]: mismatched types
--> $DIR/fn-pointer-mismatch.rs:42:30
|
LL | let d: &fn(u32) -> u32 = foo;
| --------------- ^^^ expected `&fn(u32) -> u32`, found fn item
| |
| expected due to this
|
= note: expected reference `&fn(_) -> _`
found fn item `fn(_) -> _ {foo}`
help: consider using a reference
|
LL | let d: &fn(u32) -> u32 = &foo;
| +
```
Previously we'd point at the whole expression for replacement, instead of marking what was being added.
We could also modify the suggestions for `&(name as fn())`, but for that we require storing more accurate spans than we have now.
This code detects the case where one of the borrows is inside the
let init expr while the other end is not. If that happens, we don't
want to suggest adding a semicolon, because it won't work.
Implement MIR lowering for unsafe binders
This is the final bit of the unsafe binders puzzle. It implements MIR, CTFE, and codegen for unsafe binders, and enforces that (for now) they are `Copy`. Later on, I'll introduce a new trait that relaxes this requirement to being "is `Copy` or `ManuallyDrop<T>`" which more closely models how we treat union fields.
Namely, wrapping unsafe binders is now `Rvalue::WrapUnsafeBinder`, which acts much like an `Rvalue::Aggregate`. Unwrapping unsafe binders are implemented as a MIR projection `ProjectionElem::UnwrapUnsafeBinder`, which acts much like `ProjectionElem::Field`.
Tracking:
- https://github.com/rust-lang/rust/issues/130516
tests: Port `symbol-mangling-hashed` to rmake.rs
Part of #121876.
This PR supersedes #128567 and is co-authored with `@lolbinarycat.`
### Summary
This PR ports `tests/run-make/symbol-mangling-hashed` to rmake.rs. Notable differences when compared to the Makefile version includes:
- It's no longer limited to linux + x86_64 only. In particular, this now is exercised on darwin and windows (esp. msvc) too.
- The test uses `object` crate to be more precise in the filtering, and avoids relying on parsing the human-readable `nm` output for *some* `nm` in the given environment (which isn't really a thing on msvc anyway, and `llvm-nm` doesn't handle msvc dylibs AFAICT).
- Dump the symbols satisfying various criteria on test failure to make it hopefully less of a pain to debug if it ever fails in CI.
### Review advice
- Best reviewed commit-by-commit.
- I'm not *super* sure about the msvc logic, would benefit from a MSVC (PE/COFF) expert taking a look.
---
try-job: x86_64-msvc-1
try-job: i686-msvc-1
try-job: i686-mingw
try-job: x86_64-mingw-1
try-job: x86_64-apple-1
try-job: aarch64-apple
try-job: test-various
Use proper type when applying deref adjustment in const
When applying a deref adjustment to some type `Wrap<T>` which derefs to `T`, we were checking that `T: ~const Deref`, not `Wrap<T>: ~const Deref` like we should have been.
r? project-const-traits
Fixes#136273Fixes#135210 -- I just deleted the test since the regression test is uninteresting
Manually walk into WF obligations in `BestObligation` proof tree visitor
When we encounter a `WellFormed` obligation in the `BestObligation` proof tree visitor, ignore the proof tree and call `wf::unnormalized_obligations` to derive well-formed obligations with the correct cause codes. This is to avoid having to replicate the somewhat delicate logic that `wf.rs` does to set up its obligation causes... Don't see a better way to do this.
vibes?? r? lcnr
Make it so more type-system types can be printed in a shortened version (like `Predicate`s).
Centralize printing the information about the "full type name path".
Make the "long type path" for the file where long types are written part of `Diag`, so that it becomes easier to keep track of it, and ensure it will always will be printed out last in the diagnostic by making its addition to the output implicit.
Tweak the shortening of types in "expected/found" labels.
Remove dead file `note.rs`.
Insert null checks for pointer dereferences when debug assertions are enabled
Similar to how the alignment is already checked, this adds a check
for null pointer dereferences in debug mode. It is implemented similarly
to the alignment check as a `MirPass`.
This inserts checks in the same places as the `CheckAlignment` pass and additionally
also inserts checks for `Borrows`, so code like
```rust
let ptr: *const u32 = std::ptr::null();
let val: &u32 = unsafe { &*ptr };
```
will have a check inserted on dereference. This is done because null references
are UB. The alignment check doesn't cover these places, because in `&(*ptr).field`,
the exact requirement is that the final reference must be aligned. This is something to
consider further enhancements of the alignment check.
For now this is implemented as a separate `MirPass`, to make it easy to disable
this check if necessary.
This is related to a 2025H1 project goal for better UB checks in debug
mode: https://github.com/rust-lang/rust-project-goals/pull/177.
r? `@saethlin`
Compiler: Finalize dyn compatibility renaming
Update the Reference link to use the new URL fragment from https://github.com/rust-lang/reference/pull/1666 (this change has finally hit stable). Fixes a FIXME.
Follow-up to #130826.
Part of #130852.
~~Blocking it on #133372.~~ (merged)
r? ghost
[rustdoc] Add `--extract-doctests` command-line flag
Part of https://github.com/rust-lang/rust/issues/134529.
It was discussed with the Rust-for-Linux project recently that they needed a way to extract doctests so they can modify them and then run them more easily (look for "a way to extract doctests" [here](https://github.com/Rust-for-Linux/linux/issues/2)).
For now, I output most of `ScrapedDoctest` fields in JSON format with `serde_json`. So it outputs the following information:
* filename
* line
* langstr
* text
cc `@ojeda`
r? `@notriddle`
Similar to how the alignment is already checked, this adds a check
for null pointer dereferences in debug mode. It is implemented similarly
to the alignment check as a MirPass.
This is related to a 2025H1 project goal for better UB checks in debug
mode: https://github.com/rust-lang/rust-project-goals/pull/177.
The blessed expectations were recently removed because they were only
checked via the compare-mode. This switches to explicit revisions to
ensure it doesn't happen again.
- `assignment-to-differing-field`
- `polonius-smoke-test`
- `subset-relations`