Fix normalization overflow ICEs in monomorphization
Fixesrust-lang/rust#92004Fixesrust-lang/rust#92470Fixesrust-lang/rust#95134Fixesrust-lang/rust#105275Fixesrust-lang/rust#105937
Fixes rust-lang/rust#117696-2
Fixesrust-lang/rust#118590Fixesrust-lang/rust#122823Fixesrust-lang/rust#131342Fixesrust-lang/rust#139659
## Analysis:
The causes of these issues are similar. They contain generic recursive functions that can be instantiated with different args infinitely at monomorphization stage.
Ideally this should be caught by the [`check_recursion_limit`](c0bb3b98bb/compiler/rustc_monomorphize/src/collector.rs (L468)) function. The reality is that normalization can reach recursion limit earlier than monomorphization's check because they calculate depths in different ways.
Since normalization is called everywhere, ICEs appear in different locations.
## Fix:
If we abort on overflow with `TypingMode::PostAnalysis` in the trait solver, it would also catch these errors.
The main challenge is providing good diagnostics for them. So it's quite natural to put the check right before these normalization happening.
I first tried to check the whole MIR body's normalization and `references_error`. (As elaborate_drop handles normalization failure by [returning `ty::Error`](c0bb3b98bb/compiler/rustc_mir_transform/src/elaborate_drop.rs (L514-L519)).)
It turns out that checking all `Local`s seems sufficient.
These types are gonna be normalized anyway. So with cache, these checks shouldn't be expensive.
This fixes these ICEs for both the next and old solver, though I'm not sure the change I made to the old solver is proper. Its overflow handling looks convoluted thus I didn't try to fix it more "upstream".
Perform unused assignment and unused variables lints on MIR.
Rebase of https://github.com/rust-lang/rust/pull/101500
Fixes https://github.com/rust-lang/rust/issues/51003.
The first commit moves detection of uninhabited types from the current liveness pass to MIR building.
In order to keep the same level of diagnostics, I had to instrument MIR a little more:
- keep for which original local a guard local is created;
- store in the `VarBindingForm` the list of introducer places and whether this was a shorthand pattern.
I am not very proud of the handling of self-assignments. The proposed scheme is in two parts: first detect probable self-assignments, by pattern matching on MIR, and second treat them specially during dataflow analysis. I welcome ideas.
Please review carefully the changes in tests. There are many small changes to behaviour, and I'm not sure all of them are desirable.
Rehome 30 `tests/ui/issues/` tests to other subdirectories under `tests/ui/` [#4 of Batch #2]
Part of rust-lang/rust#133895
Methodology:
1. Refer to the previously written `tests/ui/SUMMARY.md`
2. Find an appropriate category for the test, using the original issue thread and the test contents.
3. Add the issue URL at the bottom (not at the top, as that would mess up stderr line numbers)
4. Rename the tests to make their purpose clearer
Inspired by the methodology that `@Kivooeo` was using.
r? `@jieyouxu`
Validate CopyForDeref and DerefTemps better and remove them from runtime MIR
(split from my WIP rust-lang/rust#145344)
This PR:
- Removes `Rvalue::CopyForDeref` and `LocalInfo::DerefTemp` from runtime MIR
- Using a new mir pass `EraseDerefTemps`
- `CopyForDeref(x)` is turned into `Use(Copy(x))`
- `DerefTemp` is turned into `Boring`
- Not sure if this part is actually necessary, it made more sense in rust-lang/rust#145344 with `DerefTemp` storing actual data that I wanted to keep from having to be kept in sync with the rest of the body in runtime MIR
- Checks in validation that `CopyForDeref` and `DerefTemp` are only used together
- Removes special handling for `CopyForDeref` from many places
- Removes `CopyForDeref` from `custom_mir` reverting rust-lang/rust#111587
- In runtime MIR simple copies can be used instead
- In post cleanup analysis MIR it was already wrong to use due to the lack of support for creating `DerefTemp` locals
- Possibly this should be its own PR?
- Adds an argument to `deref_finder` to avoid creating new `DerefTemp`s and `CopyForDeref` in runtime MIR.
- Ideally we would just avoid making intermediate derefs instead of fixing it at the end of a pass / during shim building
- Removes some usages of `deref_finder` that I found out don't actually do anything
r? oli-obk
cmse: improve error messages
tracking issue: https://github.com/rust-lang/rust/issues/81391
tracking issue: https://github.com/rust-lang/rust/issues/75835
Improves the cmse error messages (e.g. by using more accurate spans), and attempts to clean up the control flow a bit. This is partially in preparation for one final addition: warnings when `union` types or types with niches cross the security boundary. That will be a folllow-up.
Meant to be reviewed commit-by-commit
r? ``@davidtwco``
Fix double warnings on `#[no_mangle]`
Fixes 2 out of 3 cases in https://github.com/rust-lang/rust/issues/147417
The fix on closures removes the old error and marks closures as an error target.
The fix on consts adds `AllowSilent` to to ignore a target, and uses the old error because that one has a nice suggestion.
r? ````@jdonszelmann````
clarify wording of match ergonomics diagnostics (`rust_2024_incompatible_pat` lint and error)
Partially addresses rust-lang/rust#143557:
- Uses different wording than the Edition Guide chapter, to hopefully stand alone a bit better. Instead of referring to the "default binding mode", it now talks about what can't be written "within elided reference patterns". I ended up going with "elided" instead of "implicit" in hope that it reads bit less like it should behave the same as an explicit reference pattern, but I'm not totally happy with that wording.
- The explanatory note still points to where the default binding mode was introduced, but only refers to its effect, not what we call it. How that relates to the rest of the diagnostic may still be a bit of a puzzle, but hopefully it isn't too much of one? It also doesn't make sense anymore for the case of `&` written under a by-ref binding mode, so I've left the note out in that case (but kept the label). It's more cramped, but talking about binding modes would feel like a non-sequitur for the error about `&` patterns without further explanation.
- Links to the stable version of the Edition Guide instead of the nightly version. It looks like almost every link to the Edition Guide in diagnostics is to the nightly version, presumably for the same reason as here: the diagnostics were added before the new Edition was stabilized, then never updated. I'll make a separate PR to clean up the others.
This only changes the diagnostic messages, not the code suggestion or the Edition Guide.
r? `@Nadrieril` or reassign
sort attribute targets for more consistent error messages
In this PR I noticed that we don't sort attribute targets, so a rather trivial change to the source changed the ordering in an error message even though its meaning stayed the same.
See: https://github.com/rust-lang/rust/pull/147418#discussion_r2410852750
I think sorting might be a good thing to do in general. I also prefer it when reading error messages. Quite a few tests changed, but not in meaning, only sorting order obviously.
r? `@jieyouxu`
Use globals instead of metadata for std::autodiff
LLVM's Metadata is quite fragile. In debug builds we use incremental compilation, which caused the metadata to be dropped. With this change we use named globals instead of metadata to instruct Enzyme how to differentiate functions.
Globals are proper llvm values and thus can't be dropped. Also added an incremental/dbg test which now passes, to unblock the EnzymeAD CI which wants to run Rust autodiff tests.
r? compiler
rename `select_where_possible` and `select_all_or_error`
r? `@lcnr`
I find that people get confused by what these methods do. The verb "select" is not really that helpful and is just a reference to somewhat of an implementation detail of the trait solvers that doesn't even apply to most obligation kinds.
I went with `try_evaluate_obligations` and `evaluate_obligations_error_on_ambiguity`. This maintains consistency with the new solvers `evalute_goal` entry point. it's unfortunate that we say obligations rather than goals but this maintains consistency with `register_obligation` functions which I think is a good thing. In the long term possibly we rename `Obligation` or `Goal` 🤷♀️
Rollup of 8 pull requests
Successful merges:
- rust-lang/rust#146865 (kcfi: only reify trait methods when dyn-compatible)
- rust-lang/rust#147205 (Add a new `wasm32-wasip3` target to Rust)
- rust-lang/rust#147322 (cg_llvm: Consistently import `llvm::Type` and `llvm::Value`)
- rust-lang/rust#147398 (Fix; correct placement of type inference error for method calls)
- rust-lang/rust#147410 (Update `S-waiting-on-team` refs to new `S-waiting-on-{team}` labels)
- rust-lang/rust#147422 (collect-license-metadata: Print a diff of the expected output)
- rust-lang/rust#147431 (compiletest: Read the whole test file before parsing directives)
- rust-lang/rust#147433 (Fix doc comment)
Failed merges:
- rust-lang/rust#147390 (Use globals instead of metadata for std::autodiff)
r? `@ghost`
`@rustbot` modify labels: rollup
Add a new `wasm32-wasip3` target to Rust
This commit adds a new tier 3 target to rustc, `wasm32-wasip3`. This follows in the footsteps of the previous `wasm32-wasip2` target and is used to represent binding to the WASIp3 set of APIs managed by the WASI subgroup to the WebAssembly Community Group.
As of now the WASIp3 set of APIs are not finalized nor standardized. They're in the process of doing so and the current trajectory is to have the APIs published in December of this year. The goal here is to get the wheels turning in Rust to have the target in a
more-ready-than-nonexistent state by the time this happens in December.
For now the `wasm32-wasip3` target looks exactly the same as `wasm32-wasip2` except that `target_env = "p3"` is specified. This indicates to crates in the ecosystem that WASIp3 APIs should be used, such as the [`wasip3` crate]. Over time this target will evolve as implementation in guest toolchains progress, notably:
* The standard library will use WASIp3 APIs natively once they're finalized in the WASI subgroup.
* Support through `wasi-libc` will be updated to use WASIp3 natively which Rust will then transitively use.
* Longer-term, features such as cooperative multithreading will be added to the WASIp3-track of targets to enable using `std::thread`, for example, on this target.
These changes are all expected to be non-breaking changes for users of this target. Runtimes supporting WASIp3, currently Wasmtime and Jco, support WASIp2 APIs as well and will work with components whether or not they import WASIp2, both WASIp2 and WASIp3, or just WASIp3 APIs. This means that changing the internal implementation details of libstd over time is expected to be a non-breaking change.
[`wasip3` crate]: https://crates.io/crates/wasip3
kcfi: only reify trait methods when dyn-compatible
fixes https://github.com/rust-lang/rust/issues/146853
Only generate a `ReifyShim` for trait method calls if the trait is dyn-compatible.
Until now kcfi would generate a `ReifyShim` whenever a trait method was cast to a function pointer. But technically the shim is only needed for dyn-compatible traits (where the method might end up in a vtable).
Up to this point that was only slightly inefficient, but in combination with c-variadic trait methods it is wrong. For c-variadic trait methods the generated shim is incorrect, and that is why c-variadic methods make a trait no longer dyn-compatible: we should simply never generate a `ReifyShim` that is c-variadic.
With this change the documentation on `ReifyReason` is now actually correct:
> If KCFI is enabled, creating a function pointer from a method on a dyn-compatible trait. This includes the case of converting `::call`-like methods on closure-likes to function pointers.
cc ```@maurer``` ```@workingjubilee```
r? ```@rcvalle```
Rollup of 7 pull requests
Successful merges:
- rust-lang/rust#145943 (stdlib docs: document lifetime extension for `format_args!`'s arguments)
- rust-lang/rust#147243 (cmse: disallow `impl Trait` in `cmse-nonsecure-entry` return types)
- rust-lang/rust#147402 ([rustdoc] Don't serialize & deserialize data that doesn't go OTW)
- rust-lang/rust#147418 (Fix target list of `link_section`)
- rust-lang/rust#147429 (Print tip for human error format in runtest)
- rust-lang/rust#147441 (Fix comments error for Provenance impls)
- rust-lang/rust#147442 (c-variadic: fix thir-print for `...` without a pattern)
r? `@ghost`
`@rustbot` modify labels: rollup
cmse: disallow `impl Trait` in `cmse-nonsecure-entry` return types
tracking issue: https://github.com/rust-lang/rust/issues/75835
fixes https://github.com/rust-lang/rust/issues/147242
Refactors some logic to be more robust in the future, and then disallows `impl Trait` as a return type for the cmse ABIs.
The `is_valid_cmse_output_layout` function disallows `union` values like before. That is not entirely correct, but preserves the current behavior. Some additional logic is needed for `union` values (and any types where parts may be uninitialized) that I'll tackle in a later PR.
can be reviewed commit-by-commit.
r? types
Prevent downstream `impl DerefMut for Pin<LocalType>`
The safety requirements for [`PinCoerceUnsized`](https://doc.rust-lang.org/stable/std/pin/trait.PinCoerceUnsized.html) are essentially that the type does not have a malicious `Deref` or `DerefMut` impl. However, the `Pin` type is fundamental, so the end-user can provide their own implementation of `DerefMut` for `Pin<&SomeLocalType>`, so it's possible for `Pin` to have a malicious `DerefMut` impl. This unsoundness is known as rust-lang/rust#85099.
Unfortunately, this means that the implementation of `PinCoerceUnsized` for `Pin` is currently unsound. To fix that, modify the impl so that it becomes impossible for downstream crates to provide their own implementation of `DerefMut` for `Pin` by abusing a hidden struct that is not fundamental.
This PR is a breaking change, but it fixesrust-lang/rust#85099. The PR supersedes rust-lang/rust#144896.
r? lcnr
