Windows x86: Change i128 to return via the vector ABI
Clang and GCC both return `i128` in xmm0 on windows-msvc and windows-gnu. Currently, Rust returns the type on the stack. Add a calling convention adjustment so we also return scalar `i128`s using the vector ABI, which makes our `i128` compatible with C.
In the future, Clang may change to return `i128` on the stack for its `-msvc` targets (more at [1]). If this happens, the change here will need to be adjusted to only affect MinGW.
Link: https://github.com/rust-lang/rust/issues/134288 (does not fix) [1]
try-job: x86_64-msvc
try-job: x86_64-msvc-ext1
try-job: x86_64-mingw-1
try-job: x86_64-mingw-2
Add some tracing to core bootstrap logic
Follow-up to #135391.
### Summary
Add some initial tracing logging to bootstrap, focused on the core logic (in this PR).
Also:
- Adjusted tracing-tree style to not use indent lines (I found that more distracting than helpful).
- Avoid glob-importing `tracing` items.
- Improve the rustc-dev-guide docs on bootstrap tracing.
### Example output
```bash
$ BOOTSTRAP_TRACING=bootstrap=TRACE ./x check src/bootstrap
```
r? bootstrap
compiler_fence: fix example
The old example was wrong, an acquire fence is required in the signal handler. To make the point more clear, I changed the "data" variable to use non-atomic accesses.
Fixes https://github.com/rust-lang/rust/issues/133014
Fix tests on LLVM 20
For sparcv8plus.rs, duplicate the test for LLVM 19 and LLVM 20. LLVM 20 resolves one of the FIXME in the test.
For x86_64-bigint-add.rs split the check lines for LLVM 19 and LLVM 20. The difference in codegen here is due to a difference in unroll factor, which I believe is not what the test is interested in.
Fixes https://github.com/rust-lang/rust/issues/132957.
Fixes https://github.com/rust-lang/rust/issues/133754.
Get rid of `mir::Const::from_ty_const`
This function is strange, because it turns valtrees into `mir::Const::Value`, but the rest of the const variants stay as type system consts.
All of the callsites except for one in `instsimplify` (array length simplification of `ptr_metadata` call) just go through the valtree arm of the function, so it's easier to just create a `mir::Const` directly for those.
For the instsimplify case, if we have a type system const we should *keep* having a type system const, rather than turning it into a `mir::Const::Value`; it doesn't really matter in practice, though, bc `usize` has no padding, but it feels more principled.
It seems one can't overwrite a cache entry:
```
Failed to save: Unable to reserve cache with key linkcheck--0.8.1, another job may be creating this cache. More details: Cache already exists. Scope: refs/heads/master, Key: linkcheck--0.8.1, Version: 33f8fd511bed9c91c40778bc5c27cb58425caa894ab50f9c5705d83cb78660e0
Warning: Cache save failed.
```
A proper solution is to use `restore-keys`:
https://github.com/actions/cache/blob/main/tips-and-workarounds.md#update-a-cache
Reword resolve errors caused by likely missing crate in dep tree
Reword label and add `help`:
```
error[E0432]: unresolved import `some_novel_crate`
--> f704.rs:1:5
|
1 | use some_novel_crate::Type;
| ^^^^^^^^^^^^^^^^ use of unresolved module or unlinked crate `some_novel_crate`
|
= help: if you wanted to use a crate named `some_novel_crate`, use `cargo add some_novel_crate` to add it to your `Cargo.toml`
```
Fix#133137.
Add `#[optimize(none)]`
cc #54882
This extends the `optimize` attribute to add `none`, which corresponds to the LLVM `OptimizeNone` attribute.
Not sure if an MCP is required for this, happy to file one if so.
Update cargo
5 commits in 045bf21b36a2e1f3ed85e38278d1c3cc4305e134..cecde95c119a456c30e57d3e4b31fff5a7d83df4
2025-01-17 14:59:36 +0000 to 2025-01-24 17:15:24 +0000
- Remove unused `-C link-arg=-fuse-ld=lld` (rust-lang/cargo#15097)
- Remove `unsafe` by using `LazyLock` (rust-lang/cargo#15096)
- Print globs when workspace members can't be found (rust-lang/cargo#15093)
- Make --allow-dirty imply --allow-staged (rust-lang/cargo#15013)
- fix(config): When merging, replace rather than combining specific configuration keys (rust-lang/cargo#15066)
Rollup of 9 pull requests
Successful merges:
- #135415 (Add `File already exists` error doc to `hard_link` function)
- #135581 (Separate Builder methods from tcx)
- #135728 (document order of items in iterator from drain)
- #135749 (Do not assume const params are printed after type params)
- #135829 (Rustc dev guide subtree update)
- #135938 (Add memory layout documentation to generic NonZero<T>)
- #135949 (Use short type string in E0308 secondary span label)
- #135976 (Don't drop types with no drop glue when building drops for tailcalls)
- #135998 ([rustdoc] Fix indent of trait items on mobile)
r? `@ghost`
`@rustbot` modify labels: rollup
Don't drop types with no drop glue when building drops for tailcalls
this is required as otherwise drops of `&mut` refs count as a usage of a
'two-phase temporary' causing an ICE.
fixes#128097
The underlying issue is that the current code generates drops for `&mut` which are later counted as a second use of a two-phase temporary:
`bat t.rs -p`
```rust
#![expect(incomplete_features)]
#![feature(explicit_tail_calls)]
fn f(x: &mut ()) {
let _y = String::new();
become f(x);
}
fn main() {}
```
`rustc t.rs -Zdump_mir=f`
```text
error: internal compiler error: compiler/rustc_borrowck/src/borrow_set.rs:298:17: found two uses for 2-phase borrow temporary _4: bb2[1] and bb3[0]
--> t.rs:6:5
|
6 | become f(x);
| ^^^^^^^^^^^
thread 'rustc' panicked at compiler/rustc_borrowck/src/borrow_set.rs:298:17:
Box<dyn Any>
stack backtrace:
[REDACTED]
error: aborting due to 1 previous error
```
`bat ./mir_dump/t.f.-------.renumber.0.mir -p -lrust`
```rust
// MIR for `f` 0 renumber
fn f(_1: &mut ()) -> () {
debug x => _1;
let mut _0: ();
let mut _2: !;
let _3: std::string::String;
let mut _4: &mut ();
scope 1 {
debug _y => _3;
}
bb0: {
StorageLive(_3);
_3 = String::new() -> [return: bb1, unwind: bb4];
}
bb1: {
FakeRead(ForLet(None), _3);
StorageLive(_4);
_4 = &mut (*_1);
drop(_3) -> [return: bb2, unwind: bb3];
}
bb2: {
StorageDead(_3);
tailcall f(Spanned { node: move _4, span: t.rs:6:14: 6:15 (#0) });
}
bb3 (cleanup): {
drop(_4) -> [return: bb4, unwind terminate(cleanup)];
}
bb4 (cleanup): {
resume;
}
}
```
Note how `_4 is moved into the tail call in `bb2` and dropped in `bb3`.
This PR adds a check that the locals we drop need dropping.
r? `@oli-obk` (feel free to reassign, I'm not sure who would be a good reviewer, but thought you might have an idea)
cc `@beepster4096,` since you wrote the original drop implementation.
Use short type string in E0308 secondary span label
We were previously printing the full type on the "this expression has type" label.
```
error[E0308]: mismatched types
--> $DIR/secondary-label-with-long-type.rs:8:9
|
LL | let () = x;
| ^^ - this expression has type `((..., ..., ..., ...), ..., ..., ...)`
| |
| expected `((..., ..., ..., ...), ..., ..., ...)`, found `()`
|
= note: expected tuple `((..., ..., ..., ...), ..., ..., ...)`
found unit type `()`
= note: the full type name has been written to '$TEST_BUILD_DIR/diagnostic-width/secondary-label-with-long-type/secondary-label-with-long-type.long-type-3987761834644699448.txt'
= note: consider using `--verbose` to print the full type name to the console
```
Reported in a comment of #135919.
Add memory layout documentation to generic NonZero<T>
The documentation I've added is based on the same Layout documentation that appears on the other `NonZero*` types. For example see [the Layout docs on `NonZeroI8`](https://doc.rust-lang.org/std/num/type.NonZeroI8.html#layout-1).
Jakub Beránek
Boxy
许杰友 Jieyou Xu (Joe)
yegeunyang
Michael Howell
Joren-vanGoethem
bors
León Orell Valerian Liehr
Noah Lev
Tshepang Mbambo
Eric Huss
Martin Liska
Ben Kimock
The Miri Cronjob Bot
Yuki Okushi
Matthias Krüger