never patterns: suggest `!` patterns on non-exhaustive matches
When a match is non-exhaustive we now suggest never patterns whenever it makes sense.
r? ``@compiler-errors``
Reject overly generic assoc const binding types
Split off from #119385 to make #119385 easier to review.
---
In the *instantiated* type of assoc const bindings
1. reject **early-bound generic params**
* Provide a rich error message instead of ICE'ing ([#108271](https://github.com/rust-lang/rust/issues/108271)).
* This is a temporary and semi-artificial restriction until the arrival of *generic const generics*.
* It's quite possible that rustc could already perfectly support this subset of generic const generics if we just removed some checks (some `.no_bound_vars().expect(…)`) but even if that was the case, I'd rather gate it behind a new feature flag. Reporting an error instead of ICE'ing is a good first step towards an eventual feature gate error.
2. reject **escaping late-bound generic params**
* They lead to ICEs before & I'm pretty sure that they remain incorrect even in a world with *generic const generics*
---
Together with #118668 & #119385, this supersedes #118360.
Fixes#108271.
Rollup of 8 pull requests
Successful merges:
- #122480 (Avoid various uses of `Option<Span>` in favor of using `DUMMY_SP` in the few cases that used `None`)
- #122567 (Remove fixme about LLVM basic block naming)
- #122588 (less useless filter calls in imported_source_file)
- #122647 (add_retag: ensure box-to-raw-ptr casts are preserved for Miri)
- #122649 (Update the minimum external LLVM to 17)
- #122680 (Do not eat nested expressions' results in `MayContainYieldPoint` format args visitor)
- #122683 (add missing test: expected paren or brace in macro)
- #122689 (Add missing `try_visit` calls in visitors.)
r? `@ghost`
`@rustbot` modify labels: rollup
```
error: `S2<'_>` is forbidden as the type of a const generic parameter
--> $DIR/lifetime-in-const-param.rs:5:23
|
LL | struct S<'a, const N: S2>(&'a ());
| ^^
|
= note: the only supported types are integers, `bool` and `char`
help: add `#![feature(adt_const_params)]` to the crate attributes to enable more complex and user defined types
|
LL + #![feature(adt_const_params)]
|
```
Fix#55941.
A bit of an inelegant fix but given that the error is created only
after call to `const_eval_poly()` and that the calling function
cannot propagate the error anywhere else, the error has to be
explicitly handled inside `mono_item.rs`.
Do not eat nested expressions' results in `MayContainYieldPoint` format args visitor
#121563 unintentionally changed the `MayContainYieldPoint` format args visitor behavior, now missing yield points in nested expressions, as seen in #122674.
The walk can find a yield point in an expression but it was ignored.
r? ``@petrochenkov`` as the reviewer of #121563
cc ``@Jarcho`` as the author
Fixes#122674.
We're in the 1.77 release week. #121563 will land on 1.78 but beta is still 1.77.9: this PR will likely need to be backported soon after beta is cut.
Update the minimum external LLVM to 17
With this change, we'll have stable support for LLVM 17 and 18.
For reference, the previous increase to LLVM 16 was #117947.
add_retag: ensure box-to-raw-ptr casts are preserved for Miri
In https://github.com/rust-lang/rust/pull/122233 I added `retag_box_to_raw` not realizing that we can already do `addr_of_mut!(*bx)` to turn a box into a raw pointer without an intermediate reference. We just need to ensure this information is preserved past the ElaborateBoxDerefs pass.
r? ``@oli-obk``
Remove fixme about LLVM basic block naming
~This may be a small perf win.~
Originally, this PR implemented the fixme, but it didn't have any measurable perf improvement.
r? ``@ghost``
Avoid various uses of `Option<Span>` in favor of using `DUMMY_SP` in the few cases that used `None`
based on #122471
`DUMMY_SP` is already the sentinel value we have that says "no span". We don't need to wrap these `Span`s in a separate `Option`.
Enable frame pointers for the standard library
There's been a few past experiments for enabling frame pointers for all our artifacts. I don't think that frame pointers in the distributed compiler are nearly as useful as frame pointers in the standard library. Our users are much more likely to be profiling apps written in Rust than they are profiling the Rust compiler.
So yeah it would be cool to have frame pointers in the compiler, but much more of the value is having them on the precompiled standard library. That's what this PR does.
[`map_entry`]: call the visitor on the local's `else` block
Fixes#12489
The lint already has all the logic it needs for figuring out if it can or can't suggest a closure if it sees control flow expressions like `break` or `continue`, but it was ignoring the local's else block, which meant that it didn't see the `return None;` in a `let..else`.
changelog: [`map_entry`]: suggest `if let` instead of a closure when `return` expressions exist in the else block of a `let..else`
Rollup of 4 pull requests
Successful merges:
- #122639 (Fix typos)
- #122654 (interpret/memory: explain why we use == on bool)
- #122656 (simplify_cfg: rename some passes so that they make more sense)
- #122657 (Move `option_env!` and `env!` tests to the `env-macro` directory)
r? `@ghost`
`@rustbot` modify labels: rollup
Move `option_env!` and `env!` tests to the `env-macro` directory
This PR moves the `option_env!` tests to there own directory (`extoption_env`), matching the naming convention used by the tests for `env!` (which live in the `extenv` directory).
simplify_cfg: rename some passes so that they make more sense
I was extremely confused by `SimplifyCfg::ElaborateDrops`, since it runs way later than drop elaboration. It is used e.g. in `mir-opt/retag.rs` even though that pass doesn't care about drop elaboration at all.
"Early opt" is also very confusing since that makes it sounds like it runs early during optimizations, i.e. on runtime MIR, but actually it runs way before that.
So I decided to rename
- early-opt -> post-analysis
- elaborate-drops -> pre-optimizations
I am open to other suggestions.
