Move sched_getaffinity back to Linux
This reverts commit c1a3f8576ea12b0bed68ad3dedf4069ca3d9816f. The shim isn't actually useful for anything, and it is untested on FreeBSD. On Linux it exists solely because std and num_cpus are trying this before falling back to `sysconf`, but on FreeBSD that's not how they work, so there's no reason I can see to have this stub shim on FreeBSD.
interpret, miri: uniform treatments of intrinsics/functions with and without return block
A long time ago we didn't have a `dest: &MPlaceTy<'tcx, Self::Provenance>` for diverging functions, and since `dest` is used so often we special-cased these non-returning intrinsics and functions so that we'd have `dest` available everywhere else. But this has changed a while ago, now only the return block `ret` is optional, and there's a convenient `return_to_block` function for dealing with the `None` case.
So there no longer is any reason to treat diverging intrinsics/functions any different from those that do return.
Use `unchecked_sub` in `split_at`
LLVM currently isn't figuring it out on its own, even in the checked version where it hypothetically could.
Before: <https://rust.godbolt.org/z/PEY38YrKs>
```llvm
bb1: ; preds = %start
%4 = getelementptr inbounds float, ptr %x.0, i64 %n
%5 = sub i64 %x.1, %n
```
After:
```llvm
bb1: ; preds = %start
%4 = getelementptr inbounds float, ptr %x.0, i64 %n
%5 = sub nuw i64 %x.1, %n
```
This is not using the wrapper because there's already a ubcheck covering it, so I don't want this to get a second one once #121571 lands.
---
This is basically the same as #108763, since `split_at` is essentially doing two `get_unchecked`s.
Various improvements to entrypoint code
This moves some code around and adds some documentation comments to make it easier to understand what's going on with the entrypoint logic, which is a bit complicated.
The only change in behavior is consolidating the error messages for unix_sigpipe to make the code slightly simpler.
Improve several `Read` implementations
- `read_to_end` and `read_to_string` for `Cursor`
- Error on OOM in `read_to_string` of `&[u8]` and `VecDeque<u8>`
- Avoid making the slices contiguous in `VecDeque::read_to_string`
- ~`read_exact` and (unstable) `read_buf_exact` for `Take`~
- ~`read_buf` for `UnixStream` and `&UnixStream`~ (moved to #123084)
- `read_to_end` for `ChildStdErr`
sync: better error in invalid synchronization primitive ID
`@devnexen` this should fix the ICE in your PR (but it won't fix the code, it will just report proper UB instead).
Fix ignored tests for formatting
This PR fixes the ignored rules in `rustfmt.toml` that were changed in https://github.com/rust-lang/rust/pull/124613 to allow formatting `rmake.rs` but ended up allowing formatting every Rust files in `tests/`.
The fix is a bit involved since we need to workaround a [`.gitignore` pattern limitation](https://git-scm.com/docs/gitignore#_pattern_format):
> An optional prefix "!" which negates the pattern; any matching file excluded by a previous pattern will become included again. It is not possible to re-include a file if a parent directory of that file is excluded. Git doesn’t list excluded directories for performance reasons, so any patterns on contained files have no effect, no matter where they are defined.
Workaround using https://stackoverflow.com/a/5534865
I tested the fix by changing the formatting in an `rmake.rs` and UI test, and verifying that only the `rmake.rs` files were formatted.
Fixes https://github.com/rust-lang/rust/pull/124613#issuecomment-2094094670
cc `@GuillaumeGomez`
r? `@onur-ozkan`
This moves some code around and adds some documentation comments to make
it easier to understand what's going on with the entrypoint logic, which
is a bit complicated.
The only change in behavior is consolidating the error messages for
unix_sigpipe to make the code slightly simpler.
update 'unsupported' message
Instead of "the interpreter", just say Miri.
Also be a more more clear about what is expected to be supported and what not (Cc https://github.com/rust-lang/miri/issues/2325).
