generator layout: ignore fake borrows
fixes#117059
We emit fake shallow borrows in case the scrutinee place uses a `Deref` and there is a match guard. This is necessary to prevent the match guard from mutating the scrutinee: fab1054e17/compiler/rustc_mir_build/src/build/matches/mod.rs (L1250-L1265)
These fake borrows end up impacting the generator witness computation in `mir_generator_witnesses`, which causes the issue in #117059. This PR now completely ignores fake borrows during this computation. This is sound as thse are always removed after analysis and the actual computation of the generator layout happens afterwards.
Only the second commit impacts behavior, and could be backported by itself.
r? types
Remove `-Z strip`.
It was stabilized as `-C strip` in November 2021. The unstable option was kept around as a temporary measure to ease the transition. Two years is more than enough!
r? `@tmandry`
Update ICU4X
This updates all ICU4X crates and regenerates rustc_baked_icu_data.
Since the new unicode license under which they are licensed does not have an SPDX identifier yet, we define some exceptions. The license has to be reviewed to make sure it is still fine to use here, but I assume that is the case.
I also added an exception for rustc_icu_data to the unexplained ignore doctest tidy lint. This is a bit hacky but the whole style.rs in tidy is a mess so I didn't want to touch it more than this small hack.
part of #112865
r? `@davidtwco` `@wesleywiser` `@Manishearth`
Extend builtin/auto trait args with error when they have >1 argument
Reuse `extend_with_error` to add error args to any auto trait (or built-in trait like `Copy` that is defined incorrectly) that has additional non-`Self` args.
Fixes#117628
Make `FatalErrorMarker` lower priority than other panics
This makes `FatalErrorMarker` lower priority than other panics in a parallel sections. If any other panics occur, they will be unwound instead of `FatalErrorMarker`. This ensures `rustc` will exit with the correct error code on ICEs.
This fixes https://github.com/rust-lang/rust/issues/116659.
It was stabilized as `-C strip` in November 2021. The unstable option
was kept around as a temporary measure to ease the transition. Two years
is more than enough!
patterns: reject raw pointers that are not just integers
Matching against `0 as *const i32` is fine, matching against `&42 as *const i32` is not.
This extends the existing check against function pointers and wide pointers: we now uniformly reject all these pointer types during valtree construction, and then later lint because of that. See [here](https://github.com/rust-lang/rust/pull/116930#issuecomment-1784654073) for some more explanation and context.
Also fixes https://github.com/rust-lang/rust/issues/116929.
Cc `@oli-obk` `@lcnr`
Rollup of 5 pull requests
Successful merges:
- #117263 (handle the case when the change-id isn't found)
- #117282 (Recover from incorrectly ordered/duplicated function keywords)
- #117679 (tests/rustdoc-json: Avoid needless use of `no_core` and `lang_items`)
- #117702 (target: move base and target specifications)
- #117713 (Add test for reexported hidden item with `--document-hidden-items`)
r? `@ghost`
`@rustbot` modify labels: rollup
target: move base and target specifications
Follow-up to #116004.
In anticipation of later PRs where we'll want to add tidy checks to ensure that, for each target, we have a test or a platform support document or something like that, this PR moves target specifications into a directory on their own so that we can just list the files in this directory to get a list of all targets.
- Base specifications are moved to `rustc_target::spec::base`.
- Target specifications are moved to `rustc_target::spec::targets`.
- All the other source files containing types used in the target specs remain in `rustc_target::spec`.
- `rustc_target/src/spec/abi.rs` is moved to `rustc_target/src/spec/abi/mod.rs` (where there was already a `tests.rs`) for uniformity.
r? ``@petrochenkov``
Compute polonius loan scopes over the region graph
In issue #117146 a loan flows into an SCC containing a placeholder, and whose representative is an existential region. Since we currently compute loan scopes by looking at SCCs and their representatives only, polonius would compute kill points for this loan here whereas NLLs would not of course.
There are a few ways to fix this:
- don't try to be efficient by doing the computation over SCCs, and simply look for free regions and placeholders in the successors of the issuing region.
- change how the SCC representatives are picked, biasing towards placeholders over existential regions. They *shouldn't* matter much, but some downstream code may subtly depend on the current scheme (though no tests fail if we do such a change). This is for unrelated reasons also the way #116891 changes the representative computation. So that PR would also fix issue #117146.
- try to remove placeholders from the main path, and contain them to a pre-pass + a post-pass kind of polonius leak check. If possible, it would fix this issue by turning an outlives constraints to a placeholder into a constraint to 'static. This should also fix the issue, as the representative would be the free region in the SCC. We want to prototype this change to see if it's possible to try to simplify the borrowck main path from having to deal with placeholders and higher-ranked subtyping 🤞.
I'd like to take advantage of fuzzing and a crater run sooner rather than later, so that we grow more confidence that the 2 models are indeed equivalent empirically. Therefore this PR implements option 1 to fix the issue now.
We can take care of efficiency later after validation, and once we implement option 3 (which could also impact option 2 and that associated PR, maybe the lack of placeholders could remove the need to change the representative computation) to traverse SCCs and their representative again.
(Or we maybe will have some kind of naive position-dependent outlives propagation by then and this code would have been changed)
Fixes#117146.
r? `@matthewjasper`
Add -Zcross-crate-inline-threshold=yes
``@thomcc`` says this would be useful for
> seeing if it makes a difference in some code if i do it when building the sysroot, since -Zbuild-std + lto helps more than it seems like it should
And I've changed the possible values as a reference to ``@Manishearth`` saying
> LLVM's inlining heuristic is "yes".
Only use `normalize_param_env` when normalizing predicate in `check_item_bounds`
Only use the `normalize_param_env` when normalizing the item bound predicate in `check_item_bounds`, instead of using it when processing this obligation as well. This causes <BUG> to reoccur, but hopefully with better caching in the future, we can fix this would having such bad effects on perf.
This PR also fixes#117598. It turns out that the GAT predicate that we install is actually wrong -- given code like:
```
impl<'r> HasValueRef<'r> for Any {
type Database = Any;
}
```
We currently generate a predicate that looks like `<Any as HasValueRef<'r>>::Database = Any`, where `'r` is an early-bound variable. Really this GAT assumption should be universally quantified over the impl's args, i.e. `for<'r> <Any as HasValueRef<'r>>::Database = Any`, but then we'd need the binder to also include all the WC of the impl as well, which we don't support yet, lol.
To avoid `!matches!(...)`, which is hard to think about. Instead every
case now uses direct pattern matching and returns true or false.
Also add a couple of cases to the `stringify.rs` test that currently
print badly.
Method suggestion code tweaks
I was rummaging around the method suggestion code after https://github.com/rust-lang/rust/pull/117006#discussion_r1384153722 and saw a few things to simplify.
This is two unrelated commits, both in the same file. Review them separately, if you'd like.
r? estebank
Fix some clippy perf lints
`@matthiaskrgr` gave me the output of a clippy run with perf lints enabled. This PR fixes ones that I thought were worth fixing.
r? `@cuviper`
llvm-wrapper: Remove include of non-existant Vectorize.h
LLVM recently removed the header: 2400c54c37
It only contained a declaration of `createLoadStoreVectorizerPass()`, which Rust doesn't reference.
warn when using an unstable feature with -Ctarget-feature
Setting or unsetting the wrong target features can cause ABI incompatibility (https://github.com/rust-lang/rust/issues/116344, https://github.com/rust-lang/rust/issues/116558). We need to carefully audit features for their ABI impact before stabilization. I just learned that we currently accept arbitrary unstable features on stable and if they are in the list of Rust target features, even unstable, then we don't even warn about that!1 That doesn't seem great, so I propose we introduce a warning here.
This has an obvious loophole via `-Ctarget-cpu`. I'm not sure how to best deal with that, but it seems better to fix what we can and think about the other cases later, maybe once we have a better idea for how to resolve the general mess that are ABI-affecting target features.
Give a better diagnostic for missing parens in Fn* bounds
Fixes#108109
It would be nice to try and recover here, but I'm not sure it's worth the effort, especially as the bounds on the recovered function would be incorrect.
Thir unsafeck fixes
- Recognise thread local statics in THIR unsafeck
- Add suggestion for unsafe_op_in_unsafe_fn
- Fix unsafe checking of let expressions
Only instantiate binder during dyn's built-in trait candidate probe once
See UI test for demonstration of the issue.
This was "caused" by #117131, but only because we're using the `normalize_param_env` (which has been augmented with a projection clause used to normalize GATs) which features non-lifetime bound vars in it.
Fixes#117602 technically, though that's also fixed by #117542.
r? types
Build a better MIR body when errors are encountered
Doesn't really have much of an effect on its own, but it does lead to a less confusing phony MIR body being generated when an error is detected during THIR/MIR/match building. This was quite confusing when I hacked `-Zunpretty=mir` to emit `mir_built` rather than `instance_mir`.
This coincidentually also fixes#117413, but not as generally as #117416.
cc `@Nadrieril`
When not finding assoc fn on type, look for builder fn
When we have a resolution error when looking at a fully qualified path on a type, look for all associated functions on inherent impls that return `Self` and mention them to the user.
```
error[E0599]: no function or associated item named `new` found for struct `TcpStream` in the current scope
--> tests/ui/resolve/fn-new-doesnt-exist.rs:4:28
|
4 | let stream = TcpStream::new();
| ^^^ function or associated item not found in `TcpStream`
|
note: if you're trying to build a new `TcpStream` consider using one of the following associated functions:
TcpStream::connect
TcpStream::connect_timeout
--> /home/gh-estebank/rust/library/std/src/net/tcp.rs:156:5
|
156 | pub fn connect<A: ToSocketAddrs>(addr: A) -> io::Result<TcpStream> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
172 | pub fn connect_timeout(addr: &SocketAddr, timeout: Duration) -> io::Result<TcpStream> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
```
Fix#69512.
When we have a resolution error when looking at a fully qualified path
on a type, look for all associated functions on inherent impls that
return `Self` and mention them to the user.
Fix#69512.
Emit explanatory note for move errors in packed struct derives
Derive expansions for packed structs with non-`Copy` fields cause move errors because they prefer copying over borrowing since borrowing the fields of a packed struct can result in unaligned access.
This underlying cause of the errors, however, is not apparent to the user. This PR adds a diagnostic note to make it clear to the user (the new note is on the second last line):
```
tests/ui/derives/deriving-with-repr-packed-move-errors.rs:13:16
|
12 | #[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Default)]
| ----- in this derive macro expansion
13 | struct StructA(String);
| ^^^^^^ move occurs because `self.0` has type `String`, which does not implement the `Copy` trait
|
= note: `#[derive(Debug)]` triggers a move because taking references to the fields of a packed struct is undefined behaviour
= note: this error originates in the derive macro `Debug` (in Nightly builds, run with -Z macro-backtrace for more info)
```
Fixes#117406
Partially addresses #110777
