Implement intrinsics with fallback bodies
fixes#93145 (though we can port many more intrinsics)
cc #63585
The way this works is that the backend logic for generating custom code for intrinsics has been made fallible. The only failure path is "this intrinsic is unknown". The `Instance` (that was `InstanceDef::Intrinsic`) then gets converted to `InstanceDef::Item`, which represents the fallback body. A regular function call to that body is then codegenned. This is currently implemented for
* codegen_ssa (so llvm and gcc)
* codegen_cranelift
other backends will need to adjust, but they can just keep doing what they were doing if they prefer (though adding new intrinsics to the compiler will then require them to implement them, instead of getting the fallback body).
cc `@scottmcm` `@WaffleLapkin`
### todo
* [ ] miri support
* [x] default intrinsic name to name of function instead of requiring it to be specified in attribute
* [x] make sure that the bodies are always available (must be collected for metadata)
[`new_without_default`]: Now emits on const fns
While `Default::default` is not const, it can still call `const new`; there's no reason this shouldn't be linted as well.
fixes#10877
changelog: [`new_without_default`]: Now emits on const fns
Add an ErrorGuaranteed to ast::TyKind::Err (attempt 2)
This makes it more like `hir::TyKind::Err`, and avoids a `has_errors` assertion in `LoweringContext::lower_ty_direct`.
r? ```@oli-obk```
Add `ErrorGuaranteed` to `ast::LitKind::Err`, `token::LitKind::Err`.
Similar to recent work doing the same for `ExprKind::Err` (#120586) and `TyKind::Err` (#121109).
r? `@oli-obk`
Fix msg for verbose suggestions with confusable capitalization
When encountering a verbose/multipart suggestion that has changes that are only caused by different capitalization of ASCII letters that have little differenciation, expand the message to highlight that fact (like we already do for inline suggestions).
The logic to do this was already present, but implemented incorrectly.
fix: documentation of `blocks_in_conditions` lint
Updated documentation + example of `blocks_in_conditions` lint, which has been updated recently to include `match` statements as well.
changelog: none
This mostly works well, and eliminates a couple of delayed bugs.
One annoying thing is that we should really also add an
`ErrorGuaranteed` to `proc_macro::bridge::LitKind::Err`. But that's
difficult because `proc_macro` doesn't have access to `ErrorGuaranteed`,
so we have to fake it.
This makes it more like `hir::TyKind::Err`, and avoids a
`span_delayed_bug` call in `LoweringContext::lower_ty_direct`.
It also requires adding `ast::TyKind::Dummy`, now that
`ast::TyKind::Err` can't be used for that purpose in the absence of an
error emission.
There are a couple of cases that aren't as neat as I would have liked,
marked with `FIXME` comments.
When encountering a verbose/multipart suggestion that has changes
that are only caused by different capitalization of ASCII letters that have
little differenciation, expand the message to highlight that fact (like we
already do for inline suggestions).
The logic to do this was already present, but implemented incorrectly.
[`case_sensitive_file_extension_comparisons`]: Don't trigger on digits-only extensions
If we find a file extension check with only digits (`.123`), do not trigger `case_sensitive_file_extension_comparisons`.
Fixes#12252
---
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: [`case_sensitive_file_extension_comparisons`]: Don't trigger on digits-only extensions
Ignore imported items in `min_ident_chars`
Suppress the `min_ident_chars` warning for items whose name we cannot control. Do not warn for `use a::b`, but warn for `use a::b as c`, since `c` is a local identifier.
Fixes#12232
---
*Please write a short comment explaining your change (or "none" for internal only changes)*
changelog: [`min_ident_chars`]: Do not warn on non-local identifiers
[`incompatible_msrv`]: allow expressions that come from desugaring
Fixes#12273
changelog: [`incompatible_msrv`]: don't lint on the `IntoFuture::into_future` call desugared by `.await`
Suppress the `min_ident_chars` warning for items whose name we cannot
control. Do not warn for `use a::b`, but warn for `use a::b as c`, since
`c` is a local identifier.
Fixes#12232
[`implied_bounds_in_impls`]: avoid linting on overlapping associated tys
Fixes#11880
Before this change, we were simply ignoring associated types (except for suggestion purposes), because of an incorrect assumption (see the comment that I also removed).
For something like
```rs
trait X { type T; }
trait Y: X { type T; }
// Can't constrain `X::T` through `Y`
fn f() -> impl X<T = i32> + Y<T = u32> { ... }
```
We now avoid linting if the implied bound (`X<T = i32>`) "names" associated types that also exists in the implying trait (`trait Y`). Here that would be the case.
But if we only wrote `impl X + Y<T = u32>` then that's ok because `X::T` was never constrained in the first place.
I haven't really thought about how this interacts with GATs, but I think it's fine. Fine as in, it might create false negatives, but hopefully no false positives.
(The diff is slightly annoying because of formatting things. Really the only thing that changed in the if chain is extracting the `implied_by_def_id` which is needed for getting associated types from the trait, and of course actually checking for overlap)
cc `@Jarcho` ? idk if you want to review this or not. I assume you looked into this code a bit to find this bug.
changelog: [`implied_bounds_in_impls`]: avoid linting when associated type from supertrait can't be constrained through the implying trait bound
[`mem_replace_with_default`] No longer triggers on unused expression
changelog:[`mem_replace_with_default`]: No longer triggers on unused expression
Change [`mem_replace_with_default`] to not trigger on unused expression because the lint from `#[must_use]` handle this case better.
fixes: #5586
Minor refactor format-args
* Move all linting logic into a single format implementations struct
This should help with the future format-args improvements.
**NOTE TO REVIEWERS**: use "hide whitespace" in the github diff -- most of the code has shifted, but relatively low number of lines actually modified.
Followig up from #12274
r? `@xFrednet`
---
changelog: none
Fix async closures in CTFE
First commit renames `is_coroutine_or_closure` into `is_closure_like`, because `is_coroutine_or_closure_or_coroutine_closure` seems confusing and long.
Second commit fixes some forgotten cases where we want to handle `TyKind::CoroutineClosure` the same as closures and coroutines.
The test exercises the change to `ValidityVisitor::aggregate_field_path_elem` which is the source of #120946, but not the change to `UsedParamsNeedSubstVisitor`, though I feel like it's not that big of a deal. Let me know if you'd like for me to look into constructing a test for the latter, though I have no idea what it'd look like (we can't assert against `TooGeneric` anywhere?).
Fixes#120946
r? oli-obk cc ``@RalfJung``
Warn on references casting to bigger memory layout
This PR extends the [`invalid_reference_casting`](https://doc.rust-lang.org/rustc/lints/listing/deny-by-default.html#invalid-reference-casting) lint (*deny-by-default*) which currently lint on `&T -> &mut T` casting to also lint on `&(mut) A -> &(mut) B` where `size_of::<B>() > size_of::<A>()` (bigger memory layout requirement).
The goal is to detect such cases:
```rust
let u8_ref: &u8 = &0u8;
let u64_ref: &u64 = unsafe { &*(u8_ref as *const u8 as *const u64) };
//~^ ERROR casting references to a bigger memory layout is undefined behavior
let mat3 = Mat3 { a: Vec3(0i32, 0, 0), b: Vec3(0, 0, 0), c: Vec3(0, 0, 0) };
let mat3 = unsafe { &*(&mat3 as *const _ as *const [[i64; 3]; 3]) };
//~^ ERROR casting references to a bigger memory layout is undefined behavior
```
This is added to help people who write unsafe code, especially when people have matrix struct that they cast to simple array of arrays.
EDIT: One caveat, due to the [`&Header`](https://github.com/rust-lang/unsafe-code-guidelines/issues/256) uncertainty the lint only fires when it can find the underline allocation.
~~I have manually tested all the new expressions that warn against Miri, and they all report immediate UB.~~
r? ``@est31``
fix: ICE when array index exceeds usize
fixes#12253
This PR fixes ICE in `indexing_slicing` as it panics when the index of the array exceeds `usize`.
changelog: none
Rollup of 11 pull requests
Successful merges:
- #120765 (Reorder diagnostics API)
- #120833 (More internal emit diagnostics cleanups)
- #120899 (Gracefully handle non-WF alias in `assemble_alias_bound_candidates_recur`)
- #120917 (Remove a bunch of dead parameters in functions)
- #120928 (Add test for recently fixed issue)
- #120933 (check_consts: fix duplicate errors, make importance consistent)
- #120936 (improve `btree_cursors` functions documentation)
- #120944 (Check that the ABI of the instance we are inlining is correct)
- #120956 (Clean inlined type alias with correct param-env)
- #120962 (Add myself to library/std review)
- #120972 (fix ICE for deref coercions with type errors)
r? `@ghost`
`@rustbot` modify labels: rollup
Don't allow derive macros to silence `disallowed_macros`
fixes#12254
The implementation is a bit of a hack, but "works". A derive expanding to another derive won't work properly, but we shouldn't be linting those anyways.
changelog: `disallowed_macros`: Don't allow derive macros to silence their own expansion
Assert that params with the same *index* have the same *name*
Found this bug when trying to build libcore with the new solver, since it will canonicalize two params with the same index into *different* placeholders if those params differ by name.
