Fix ICE when validating transmuting ZST to inhabited enum
MIR validation attempts to determine the number of bytes needed to represent the size of the source type to compute the discriminant for the inhabited target enum. For a ZST source, there is no source data to use as a discriminant so no proper runtime check can be generated.
Since that should never be possible, insert a delayed bug to ensure the problem has been properly reported to the user by the type checker.
Fixesrust-lang/rust#145786
citool: cleanup `mismatched_lifetime_syntaxes` warnings
Those lifetimes are implicit earlier in the same signature, and should not be hidden in the output type.
Remove two duplicated crates
These commits remove `toml-0.5.11` and `dirs-sys-0.4.1`. There are later versions of those same crates already in the tree. Found with `cargo tree -d`.
r? ``@jieyouxu``
interpret/allocation: get_range on ProvenanceMap
Helper method to grab all provenances in a given address range for an allocation, making some logic in Miri nicer.
match exhaustiveness diagnostics: show a trailing comma on singleton tuple consructors in witness patterns (and clean up a little)
Constructor patterns of type `(T,)` are written `(pat,)`, not `(pat)`. However, exhaustiveness/usefulness diagnostics would print them as `(pat)` when e.g. providing a witness of non-exhaustiveness and suggesting adding arms to make matches exhaustive; this would result in an error when applied.
rust-analyzer already prints the trailing comma, so it doesn't need changing.
This also includes some cleanup in the second commit, with justification in the commit message.
std/sys/fd: Relax `READ_LIMIT` on Darwin
Darwin's `read`/`write` syscalls emit `EINVAL` only when `nbyte > INT_MAX`. The case `nbyte == INT_MAX` is valid, so the subtraction (`- 1`) in
```rust
const READ_LIMIT: usize = if cfg!(target_vendor = "apple") {
libc::c_int::MAX as usize - 1 // <- HERE
} else {
libc::ssize_t::MAX as usize
};
```
can be removed.
I tested that the case `nbyte == INT_MAX` is valid on various versions of macOS, including old one like Mac OS X 10.5.
The man page says:
- read() and pread() will fail if the parameter nbyte exceeds INT_MAX (link: https://keith.github.io/xcode-man-pages/read.2.html)
- write() and pwrite() will fail if the parameter nbyte exceeds INT_MAX (link: https://keith.github.io/xcode-man-pages/write.2.html)
Here are links to Darwin's code:
- [macOS 15.5] e3723e1f17/bsd/kern/sys_generic.c (L307)
- [Mac OS X 10.2] d738f90084/bsd/kern/sys_generic.c (L220)
Related PR: rust-lang/rust#38622.
opt-dist: rebuild rustc when doing static LLVM builds
when building LLVM it's obvious that in case of shared build rustc doesn't need to be recompiled, but with static builds it would be better to compile rustc again to ensure we linked proper library.
maybe I didn't understand the pipeline correctly, but it was strange for me to see that in Stage 5 LLVM is built while rustc is not
r? ```@Kobzol```
try-job: dist-x86_64-msvc
try-job: dist-x86_64-linux
change HIR typeck region uniquification handling approach
rust-lang/rust#144405 causes structural lookup of opaque types to not work during HIR typeck, so instead avoid uniquifying goals and instead only reprove them if MIR borrowck actually encounters an error.
This doesn't perfectly maintain the property that HIR typeck succeeding implies that MIR typeck succeeds, instead weakening this check to only guarantee that HIR typeck implies that MIR typeck succeeds modulo region uniquification. This means we still get the actually desirable ICEs if we MIR building is broken or we forget to check some property in HIR typeck, without having to deal with the fallout of uniquification in HIR typeck itself.
We report errors using the original obligation sources of HIR typeck so diagnostics aren't that negatively impacted either.
Here's the history of region uniquification while working on the new trait solver:
- rust-lang/rust#107981
- rust-lang/rust#110180
- rust-lang/rust#114117
- rust-lang/rust#130821
- rust-lang/rust#144405
- rust-lang/rust#145706 <- we're here 🎉
r? `@BoxyUwU`
MIR validation attempts to determine the number of bytes needed to
represent the size of the source type to compute the discriminant for
the inhabited target enum. For a ZST source, there is no source data to
use as a discriminant so no proper runtime check can be generated.
Since that should never be possible, insert a delayed bug to ensure the
problem has been properly reported to the user by the type checker.
Update cargo submodule
12 commits in 71eb84f21aef43c07580c6aed6f806a6299f5042..623d536836b4cde09ce38609232a024d5b25da81
2025-08-17 17:18:56 +0000 to 2025-08-22 19:05:52 +0000
- test(frontmatter): Match test updates in rustc (rust-lang/cargo#15878)
- chore: fix some typos in comment (rust-lang/cargo#15877)
- Add Arm64 Windows CI jobs (rust-lang/cargo#15790)
- suggest workspace hints for boolean dependencies (rust-lang/cargo#15507)
- make `UnitGenerator` public in cargo-as-a-library (rust-lang/cargo#15873)
- Linting system (rust-lang/cargo#15865)
- Switch to using native mdbook fragment redirects (rust-lang/cargo#15861)
- docs(profile): revert wrong statement of lto options' optimization (rust-lang/cargo#15855)
- docs: avoid ambiguity between update and fetch (rust-lang/cargo#15860)
- docs: mention how Cargo fetch git submodules (rust-lang/cargo#15853)
- feat(unstable): Added `-Zbuild-dir-new-layout` unstable feature (rust-lang/cargo#15848)
- Implement `host`-target substitution (rust-lang/cargo#15838)
r? ghost
