Miri: non-deterministic floating point operations in `foreign_items`
Part of [rust-lang/miri/#3555](https://github.com/rust-lang/miri/issues/3555#issue-2278914000), this pr does the `foreign_items` work.
Some things have changed since rust-lang/rust#138062 and rust-lang/rust#142514. I moved the "helpers" used for creating fixed outputs and clamping operations to their defined ranges to `math.rs`. These are now also extended to handle the floating-point operations in `foreign_items`. Tests in `miri/tests/float.rs` were changed/added.
Failing tests in `std` were extracted, run under miri with `-Zmiri-many-seeds=0..1000` and changed accordingly. Double checked with `-Zmiri-many-seeds`.
I noticed that the C standard doesn't specify the output ranges for all of its mathematical operations; it just specifies them as:
```
Returns
The sinh functions return sinh x.
```
So I used [Wolfram|Alpha](https://www.wolframalpha.com/).
emit `StorageLive` and schedule `StorageDead` for `let`-`else`'s bindings after matching
This PR removes special handling of `let`-`else`, so that `StorageLive`s are emitted and `StorageDead`s are scheduled only after pattern-matching has succeeded. This means `StorageDead`s will no longer appear for all of its bindings on the `else` branch (because they're not live yet) and its drops&`StorageDead`s will happen together like they do elsewhere, rather than having all drops first, then all `StorageDead`s.
This fixesrust-lang/rust#142056, and is therefore a breaking change. I believe it'll need a crater run and a T-lang nomination/fcp thereafter. Specifically, this makes drop-checking slightly more restrictive for `let`-`else` to match the behavior of other variable binding forms. An alternative approach could be to change the relative order of drops and `StorageDead`s for other binding forms to make drop-checking more permissive, but making that consistent would be a significantly more involved change.
r? mir
cc `````@dingxiangfei2009`````
`````@rustbot````` label +T-lang +needs-crater
Tweak auto trait errors
Make suggestions to remove params and super traits verbose and make spans more accurate.
```
error[E0567]: auto traits cannot have generic parameters
--> $DIR/auto-trait-validation.rs:6:19
|
LL | auto trait Generic<T> {}
| -------^^^
| |
| auto trait cannot have generic parameters
error[E0568]: auto traits cannot have super traits or lifetime bounds
--> $DIR/auto-trait-validation.rs:8:20
|
LL | auto trait Bound : Copy {}
| ----- ^^^^
| |
| auto traits cannot have super traits or lifetime bounds
```
```
error[E0380]: auto traits cannot have associated items
--> $DIR/issue-23080.rs:5:8
|
LL | unsafe auto trait Trait {
| ----- auto traits cannot have associated items
LL | fn method(&self) {
| ^^^^^^
```
Simplify dead code lint
This PR scratches a few itches I had when looking at that code.
The perf improvement comes from keeping the `scanned` set through several marking phases. This pretty much divides by 2 the number of HIR traversals.
Consolidate staging for `rustc_private` tools
This PR continues bootstrap refactoring, this time by consolidating staging for `Mode::ToolRustc` tools. This refactoring was in the critical path of refactoring `test`/`dist`/`clippy`/`doc` steps, and getting rid of the rmeta/rlib sysroot copy, because tools are pervasive and they are being used for a lot of things in bootstrap.
The main idea is to explicitly model the fact that a stage N `Mode::ToolRustc` tool always works with two different compilers:
- Stage N-1 rustc (`build_compiler`) builds stage N rustc (`target_compiler`)
- Rlib artifacts from stage N rustc are copied to the sysroot of stage N-1 rustc
- Stage N-1 rustc builds the (stage N) tool itself, the tool links to the rlib artifacts of the stage N rustc
Before, the code often used `compiler`, which meant sometimes the build compiler, sometimes the target compiler, and sometimes neither (looking at you, `download-rustc`). This is especially annoying when you get to a situation where you have an install step that invokes a dist step that invokes a tool build step, where *some* compiler is being propagated through, without it being clear what does that compiler represent. This refactoring hopefully makes that clearer and more explicit. It also gets rid of a few `builder.ensure(Rustc(...))` calls within bootstrap, which is always nice.
`Rustdoc` needs to be handled a bit specially, because it acts as a compiler itself, I documented that in the changes.
It wasn't practical to do these refactorings in multiple PRs, so I did it all in one PR. The meat of the change is 9ee6d1c1ed112c3dcfb5684b33772b136df0dca3.
I tested manually that `x build rustdoc` and `x build miri` still works even with `download-rustc`, although I cannot promise any extra support for `download-rustc`, IMO we will just have to reimplement it from scratch in a different way.
As usually, I did some drive-by refactorings to bootstrap, trying to document and clarify things, add more step metadata and tests.
Since these changes broke Cargo, which was incorrectly using `Mode::ToolRustc`, I also changed cargo to `ToolTarget` in this PR.
Best reviewed commit-by-commit (note that I renamed `link_compiler` to `target_compiler`, in accordance to the rest of bootstrap, in the last commit).
r? `@jieyouxu`
try-job: x86_64-gnu-aux
try-job: x86_64-msvc-ext1
Delete `tests/ui/threads-sendsync/tcp-stress.rs`
This stress test was originally introduced in 65cca4bd3fa0abe1000662014b3e3ea1420728f5 to detect a UAF in `libuv` (see rust-lang/rust#12823), but we no longer use `libuv`, so remove this test as it no longer serves its original purpose, and is causing flaky timeout failures.
Closesrust-lang/rust#144878 (by removing the test).
r? libs
Rehome 21 `tests/ui/issues/` tests to other subdirectories under `tests/ui/`
rust-lang/rust#143902 divided into smaller, easier to review chunks.
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``
uniquify root goals during HIR typeck
We need to rely on region identity to deal with hangs such as https://github.com/rust-lang/trait-system-refactor-initiative/issues/210 and to keep the current behavior of `fn try_merge_responses`.
This is a problem as borrowck starts by replacing each *occurrence* of a region with a unique inference variable. This frequently splits a single region during HIR typeck into multiple distinct regions. As we assume goals to always succeed during borrowck, relying on two occurances of a region being identical during HIR typeck causes ICE. See the now fixed examples in https://github.com/rust-lang/trait-system-refactor-initiative/issues/27 and rust-lang/rust#139409.
We've previously tried to avoid this issue by always *uniquifying* regions when canonicalizing goals. This prevents caching subtrees during canonicalization which resulted in hangs for very large types. People rely on such types in practice, which caused us to revert our attempt to reinstate `#[type_length_limit]` in https://github.com/rust-lang/rust/pull/127670. The complete list of changes here:
- rust-lang/rust#107981
- rust-lang/rust#110180
- rust-lang/rust#114117
- rust-lang/rust#130821
After more consideration, all occurrences of such large types need to happen outside of typeck/borrowck. We know this as we already walk over all types in the MIR body when replacing their regions with nll vars.
This PR therefore enables us to rely on region identity inside of the trait solver by exclusively **uniquifying root goals during HIR typeck**. These are the only goals we assume to hold during borrowck. This is insufficient as type inference variables may "hide" regions we later uniquify. Because of this, we now stash proven goals which depend on inference variables in HIR typeck and reprove them after writeback. This closes https://github.com/rust-lang/trait-system-refactor-initiative/issues/127.
This was originally part of rust-lang/rust#144258 but I've moved it into a separate PR. While I believe we need to rely on region identity to fix the performance issues in some way, I don't know whether rust-lang/rust#144258 is the best approach to actually do so. Regardless of how we deal with the hangs however, this change is necessary and desirable regardless.
r? `@compiler-errors` or `@BoxyUwU`
Remove eval_always from check_private_in_public.
This PR attempts to avoid re-computing `check_private_in_public` query. First by marking the query as non-`eval_always`, and by reducing the amount of accesses to HIR as much as possible.
Latest perf https://github.com/rust-lang/rust/pull/116316#issuecomment-3094672105 shows that we manage it. The cost is extra dep-graph bookkeeping.
Free disk space on Windows 2025 runners
I've managed to reduce the time deletion takes by:
- Using powershell, which is generally faster for filesystem operations than msys2
- Performing deletions concurrently then waiting for them all to complete
It still takes 2-10 mins but that's not too bad.
