Automatically taint when reporting errors from ItemCtxt
This isn't very robust yet, as you need to use `itemctxt.dcx()` instead of `tcx.dcx()` for it to take effect, but it's at least more convenient than sprinkling `set_tainted_by_errors` calls in individual places.
based on https://github.com/rust-lang/rust/pull/127357
r? `@fmease`
[Coverage][MCDC] Group mcdc tests and fix panic when generating mcdc code for inlined expressions.
### Changes
1. Group all mcdc tests to one directory.
2. Since mcdc instruments different mappings for boolean expressions with normal branch coverage as #125766 introduces, it would be better also trace branch coverage results in mcdc tests.
3. So far rustc does not call `CoverageInfoBuilderMethods::init_coverage` for inlined functions. As a result, it could panic if it tries to instrument mcdc statements for inlined functions due to uninitialized cond bitmaps. We can reproduce this issue by current nightly rustc and [the test](https://github.com/rust-lang/rust/pull/127234/files#diff-c81af6bf4869aa42f5c7334e3e86344475de362f673f54ce439ec75fcb5ac3e5) with flag `--release`. This patch fixes it.
Fix regression in the MIR lowering of or-patterns
In https://github.com/rust-lang/rust/pull/126553 I made a silly indexing mistake and regressed the MIR lowering of or-patterns. This fixes it.
r? `@compiler-errors` because I'd like this to be merged quickly 🙏
Consolidate region error reporting in `rustc_infer`
More work on https://github.com/rust-lang/rust/issues/127492. Separate but important step, since I'm gonna likely pull everything else here into another module.
I don't think I'm confident whether `nice_region_error` should be a submodule of the new `rustc_infer::infer::error_reporting::region` module, so I left it alone for now.
r? lcnr
Move trait selection error reporting to its own top-level module
This effectively moves `rustc_trait_selection::traits::error_reporting` to `rustc_trait_selection::error_reporting::traits`. There are only a couple of actual changes to the code, like moving the `pretty_impl_header` fn out of the specialization module for privacy reasons.
This is quite pointless on its own, but having `error_reporting` as a top-level module in `rustc_trait_selection` is very important to make sure we have a meaningful file structure for when we move **type** error reporting (and region error reporting, with which it's incredibly entangled currently) into `rustc_trait_selection`. I've opened a tracking issue here: #127492
r? lcnr
Add Natvis visualiser and debuginfo tests for `f16`
To render `f16`s in debuggers on MSVC targets, this PR changes the compiler to output `f16`s as `struct f16 { bits: u16 }`, and includes a Natvis visualiser that manually converts the `f16`'s bits to a `float` which is can then be displayed by debuggers. `gdb`, `lldb` and `cdb` tests are also included for `f16` .
`f16`/`f128` MSVC debug info issue: #121837
Tracking issue: #116909
Migrate `pass-linker-flags-flavor`, `pass-linker-flags-from-dep` and `pass-linker-flags` `run-make` tests to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
Please test on i686-msvc. Expected to fail.
try-job: aarch64-apple
Infer async closure signature from (old-style) two-part `Fn` + `Future` bounds
When an async closure is passed to a function that has a "two-part" `Fn` and `Future` trait bound, like:
```rust
use std::future::Future;
fn not_exactly_an_async_closure(_f: F)
where
F: FnOnce(String) -> Fut,
Fut: Future<Output = ()>,
{}
```
The we want to be able to extract the signature to guide inference in the async closure, like:
```rust
not_exactly_an_async_closure(async |string| {
for x in string.split('\n') { ... }
//~^ We need to know that the type of `string` is `String` to call methods on it.
})
```
Closure signature inference will see two bounds: `<?F as FnOnce<Args>>::Output = ?Fut`, `<?Fut as Future>::Output = String`. We need to extract the signature by looking through both projections.
### Why?
I expect the ecosystem's move onto `async Fn` trait bounds (which are not affected by this PR, and already do signature inference fine) to be slow. In the mean time, I don't see major overhead to supporting this "old–style" of trait bounds that were used to model async closures.
r? oli-obk
Fixes#127468Fixes#127425
std: Set `has_reliable_f16` to false for MIPS targets in build.rs
This PR makes std tests link for MIPS again (they broke with https://github.com/rust-lang/rust/pull/126608) by avoiding the following link errors. Step-by-step instructions on how to reproduce these errors in docker can be found below.
std.9e27ea-cgu.12:(.text._ZN3std3num8test_num17edc3E+0x38): undefined reference to `__gnu_f2h_ieee'
std.9e27ea-cgu.12:(.text._ZN3std3num8test_num17hdc3E+0x38): undefined reference to `__gnu_h2f_ieee'
This PR just adds one line of config in existing f16 infrastructure. It also disables four doctests that fails with the same link errors.
## Step-by-step to reproduce linking error
1. Prepare:
```sh
docker run -it ubuntu:24.10
apt update && apt install -y \
libc6-mips-cross \
libc6-mipsel-cross \
libc6-mips64-cross \
libc6-mips64el-cross \
gcc-mips-linux-gnu \
gcc-mipsel-linux-gnu \
gcc-mips64-linux-gnuabi64 \
gcc-mips64el-linux-gnuabi64 \
git curl python3 build-essential
git clone --depth 1 https://github.com/rust-lang/rust.git
cd rust
```
2. Try to link std tests for any of these 4 MIPS targets by running any one of these commands:
```sh
CC_mips_unknown_linux_gnu=mips-linux-gnu-gcc \
CARGO_TARGET_MIPS_UNKNOWN_LINUX_GNU_LINKER=mips-linux-gnu-gcc \
./x test library/std --target mips-unknown-linux-gnu
CC_mipsel_unknown_linux_gnu=mipsel-linux-gnu-gcc \
CARGO_TARGET_MIPSEL_UNKNOWN_LINUX_GNU_LINKER=mipsel-linux-gnu-gcc \
./x test library/std --target mipsel-unknown-linux-gnu
CC_mips64_unknown_linux_gnuabi64=mips64-linux-gnuabi64-gcc \
CARGO_TARGET_MIPS64_UNKNOWN_LINUX_GNUABI64_LINKER=mips64-linux-gnuabi64-gcc \
./x test library/std --target mips64-unknown-linux-gnuabi64
CC_mips64el_unknown_linux_gnuabi64=mips64el-linux-gnuabi64-gcc \
CARGO_TARGET_MIPS64EL_UNKNOWN_LINUX_GNUABI64_LINKER=mips64el-linux-gnuabi64-gcc \
./x test library/std --target mips64el-unknown-linux-gnuabi64
```
### Expected
No link error. After this PR there are no link errors.
### Actual
```
error: linking with `mips-linux-gnu-gcc` failed: exit status: 1
|
= note: LC_ALL="C" PATH="/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/x86_64-unknown-linux-gnu/bin:/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/x86_64-unknown-linux-gnu/bin:/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/x86_64-unknown-linux-gnu/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" VSLANG="1033" "mips-linux-gnu-gcc" "/tmp/rustcEtKsay/symbols.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.00.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.01.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.02.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.03.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.04.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.05.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.06.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.07.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.08.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.09.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.10.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.11.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.12.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.13.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.14.rcgu.o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.15.rcgu.o" "-Wl,--as-needed" "-L" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps" "-L" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/release/deps" "-L" "/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/mips-unknown-linux-gnu/lib" "-Wl,-Bstatic" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/librand_xorshift-deb32232a867c543.rlib" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/librand-5a391600dce9d98f.rlib" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/librand_core-a11cfba3d86c5298.rlib" "/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/mips-unknown-linux-gnu/lib/libtest-65b05caf5a9b99a4.rlib" "/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/mips-unknown-linux-gnu/lib/libgetopts-ba692b2f798aef60.rlib" "/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/mips-unknown-linux-gnu/lib/libunicode_width-20ec8b475126cb0b.rlib" "/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/mips-unknown-linux-gnu/lib/librustc_std_workspace_std-c17f739fee51cc86.rlib" "-L" "/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/mips-unknown-linux-gnu/lib" "-Wl,-Bdynamic" "-lstd-124ee57a4c00deda" "-Wl,-Bstatic" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/libcompiler_builtins-bd55a137b89bc81f.rlib" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "/rust/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/mips-unknown-linux-gnu/lib" "-o" "/rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-Wl,-O1" "-nodefaultlibs" "-Wl,-z,origin" "-Wl,-rpath,$ORIGIN/../lib"
= note: /usr/lib/gcc-cross/mips-linux-gnu/12/../../../../mips-linux-gnu/bin/ld: /rust/build/x86_64-unknown-linux-gnu/stage1-std/mips-unknown-linux-gnu/release/deps/std-1cffa50fa8c43b63.std.9ee227e919a554fa-cgu.12.rcgu.o: in function `std::num::test_num':
std.9ee227e919a554fa-cgu.12:(.text._ZN3std3num8test_num17haed2ea710c1afdc3E+0x38): undefined reference to `__gnu_f2h_ieee'
/usr/lib/gcc-cross/mips-linux-gnu/12/../../../../mips-linux-gnu/bin/ld: std.9ee227e919a554fa-cgu.12:(.text._ZN3std3num8test_num17haed2ea710c1afdc3E+0x3c): undefined reference to `__gnu_f2h_ieee'
/usr/lib/gcc-cross/mips-linux-gnu/12/../../../../mips-linux-gnu/bin/ld: std.9ee227e919a554fa-cgu.12:(.text._ZN3std3num8test_num17haed2ea710c1afdc3E+0x44): undefined reference to `__gnu_h2f_ieee'
...
collect2: error: ld returned 1 exit status
error: could not compile `std` (lib test) due to 1 previous error
```
clarify `sys::unix::fd::FileDesc::drop` comment
closes#66876
simply clarifies some resource-relevant things regarding the `close` syscall to reduce the amount of search needed in other parts of the web.
Mark format! with must_use hint
Uses unstable feature https://github.com/rust-lang/rust/issues/94745
Part of #126475
First contribution to rust, please let me know if the blessing of tests is correct
Thanks `@bjorn3` for the help
Make casts of pointers to trait objects stricter
This is an attempt to `fix` https://github.com/rust-lang/rust/issues/120222 and https://github.com/rust-lang/rust/issues/120217.
This is done by adding restrictions on casting pointers to trait objects.
Before this PR the rules were as follows:
> When casting `*const X<dyn A>` -> `*const Y<dyn B>`, principal traits in `A` and `B` must refer to the same trait definition (or no trait).
With this PR the rules are changed to
> When casting `*const X<dyn Src>` -> `*const Y<dyn Dst>`
> - if `Dst` has a principal trait `DstP`,
> - `Src` must have a principal trait `SrcP`
> - `dyn SrcP` and `dyn DstP` must be the same type (modulo the trait object lifetime, `dyn T+'a` -> `dyn T+'b` is allowed)
> - Auto traits in `Dst` must be a subset of auto traits in `Src`
> - Not adhering to this is currently a FCW (warn-by-default + `FutureReleaseErrorReportInDeps`), instead of an error
> - if `Src` has a principal trait `Dst` must as well
> - this restriction will be removed in a follow up PR
This ensures that
1. Principal trait's generic arguments match (no `*const dyn Tr<A>` -> `*const dyn Tr<B>` casts, which are a problem for [#120222](https://github.com/rust-lang/rust/issues/120222))
2. Principal trait's lifetime arguments match (no `*const dyn Tr<'a>` -> `*const dyn Tr<'b>` casts, which are a problem for [#120217](https://github.com/rust-lang/rust/issues/120217))
3. No auto traits can be _added_ (this is a problem for arbitrary self types, see [this comment](https://github.com/rust-lang/rust/pull/120248#discussion_r1463835350))
Some notes:
- We only care about the metadata/last field, so you can still cast `*const dyn T` to `*const WithHeader<dyn T>`, etc
- The lifetime of the trait object itself (`dyn A + 'lt`) is not checked, so you can still cast `*mut FnOnce() + '_` to `*mut FnOnce() + 'static`, etc
- This feels fishy, but I couldn't come up with a reason it must be checked
The diagnostics are currently not great, to say the least, but as far as I can tell this correctly fixes the issues.
cc `@oli-obk` `@compiler-errors` `@lcnr`
coverage: Extract hole spans from HIR instead of MIR
This makes it possible to treat more kinds of nested item/code as holes, instead of being restricted to closures.
(It also potentially opens up the possibility of using HIR holes to modify branch or MC/DC spans, though we currently don't actually do this.)
Thus, this new implementation treats the following as holes:
- Closures (as before, including `async` and coroutines)
- All nested items
- Inline `const` (because why not)
This gives more accurate coverage reports, because lines occupied by holes don't show the execution count from the enclosing function.
Fixes#126626.
Make `push_outlives_components` into a `TypeVisitor`
This involves removing the `visited: &mut SsoHashSet<GenericArg<'tcx>>` that is being passed around the `VerifyBoundCx`. The fact that we were using it when decomposing different type tests seems sketchy, so I don't think, though it may technically result in us registering more redundant outlives components 🤷
I did end up deleting some of the comments that referred back to RFC 1214 during this refactor. I can add them back if you think they were useful.
r? lcnr
Rollup of 10 pull requests
Successful merges:
- #126841 ([`macro_metavar_expr_concat`] Add support for literals)
- #126881 (Make `NEVER_TYPE_FALLBACK_FLOWING_INTO_UNSAFE` a deny-by-default lint in edition 2024)
- #126921 (Give VaList its own home)
- #127367 (Run alloc sync tests)
- #127431 (Use field ident spans directly instead of the full field span in diagnostics on local fields)
- #127437 (Uplift trait ref is knowable into `rustc_next_trait_solver`)
- #127439 (Uplift elaboration into `rustc_type_ir`)
- #127451 (Improve `run-make/output-type-permutations` code and improve `filename_not_in_denylist` API)
- #127452 (Fix intrinsic const parameter counting with `effects`)
- #127459 (rustdoc-json: add type/trait alias tests)
r? `@ghost`
`@rustbot` modify labels: rollup
Uplift elaboration into `rustc_type_ir`
Allows us to deduplicate and consolidate elaboration (including these stupid elaboration duplicate fns i added for pretty printing like 3 years ago) so I'm pretty hyped about this change :3
r? lcnr