Use queue-based `RwLock` on more platforms
This switches over Windows 7, SGX and Xous to the queue-based `RwLock` implementation added in #110211, thereby fixing #121949 for Windows 7 and partially resolving #114581 on SGX. TEEOS can't currently be switched because it doesn't have a good thread parking implementation.
CC `@roblabla` `@raoulstrackx` `@xobs` Could you help me test this, please?
r? `@ChrisDenton` the Windows stuff should be familiar to you
zkvm: fix references to `os_str` module
The `os_str` module has been moved to `sys`. This change fixes build issues by changing `use` to point to `crate::sys::os_str`.
Rollup of 12 pull requests
Successful merges:
- #123423 (Distribute LLVM bitcode linker as a preview component)
- #123548 (libtest: also measure time in Miri)
- #123666 (Fix some typos in doc)
- #123864 (Remove a HACK by instead inferring opaque types during expected/formal type checking)
- #123896 (Migrate some diagnostics in `rustc_resolve` to session diagnostic)
- #123919 (builtin-derive: tag → discriminant)
- #123922 (Remove magic constants when using `base_n`.)
- #123931 (Don't leak unnameable types in `-> _` recover)
- #123933 (move the LargeAssignments lint logic into its own file)
- #123934 (`rustc_data_structures::graph` mini refactor)
- #123941 (Fix UB in LLVM FFI when passing zero or >1 bundle)
- #123957 (disable create_dir_all_bare test on all(miri, windows))
r? `@ghost`
`@rustbot` modify labels: rollup
libtest: also measure time in Miri
A long time ago we disabled timekeeping of the default test harness in Miri, as otherwise it would fail to run without `-Zmiri-disable-isolation`. However, since then Miri gained a "fake clock" that lets it present some deterministic notion of time when isolation is enabled.
So we could now let libtest do timekeeping again when running in Miri. That's nice as it can help detect tests that run too long. However it can also be confusing as the results with isolation can be quite different than the real time.
``@rust-lang/miri`` what do you think?
Miri on Windows: run .CRT$XLB linker section on thread-end
Hopefully fixes https://github.com/rust-lang/rust/issues/123583
First commit is originally by `@bjorn3`
r? `@oli-obk`
Cc `@ChrisDenton`
Link MSVC default lib in core
## The Problem
On Windows MSVC, Rust invokes the linker directly. This means only the objects and libraries Rust explicitly passes to the linker are used. In short, this is equivalent to passing `-nodefaultlibs`, `-nostartfiles`, etc for gnu compilers.
To compensate for this [the libc crate links to the necessary libraries](a0f5b4b213/src/windows/mod.rs (L258-L261)). The libc crate is then linked from std, thus when you use std you get the defaults back.or integrate with C/C++.
However, this has a few problems:
- For `no_std`, users are left to manually pass the default lib to the linker
- Whereas `std` has the opposite problem, using [`/nodefaultlib`](https://learn.microsoft.com/en-us/cpp/build/reference/nodefaultlib-ignore-libraries?view=msvc-170) doesn't work as expected because Rust treats them as normal libs. This is a particular problem when you want to use e.g. the debug CRT libraries in their place or integrate with C/C++..
## The solution
This PR fixes this in two ways:
- moves linking the default lib into `core`
- passes the lib to the linker using [`/defaultlib`](https://learn.microsoft.com/en-us/cpp/build/reference/defaultlib-specify-default-library?view=msvc-170). This allows users to override it in the normal way (i.e. with [`/nodefaultlib`](https://learn.microsoft.com/en-us/cpp/build/reference/nodefaultlib-ignore-libraries?view=msvc-170)).
This is more or less equivalent to what the MSVC C compiler does. You can see what this looks like in my second commit, which I'll reproduce here for convenience:
```rust
// In library/core
#[cfg(all(windows, target_env = "msvc"))]
#[link(
name = "/defaultlib:msvcrt",
modifiers = "+verbatim",
cfg(not(target_feature = "crt-static"))
)]
#[link(name = "/defaultlib:libcmt", modifiers = "+verbatim", cfg(target_feature = "crt-static"))]
extern "C" {}
```
## Alternatives
- Add the above to `unwind` and `std` but not `core`
- The status quo
- Some other kind of compiler magic maybe
This bares some discussion so I've t-libs nominated it.
Add missing `unsafe` to some internal `std` functions
Adds `unsafe` to a few internal functions that have safety requirements but were previously not marked as `unsafe`. Specifically:
- `std::sys::pal::unix:🧵:min_stack_size` needs to be `unsafe` as `__pthread_get_minstack` might dereference the passed pointer. All callers currently pass a valid initialised `libc::pthread_attr_t`.
- `std:🧵:Thread::new` (and `new_inner`) need to be `unsafe` as it requires the passed thread name to be valid UTF-8, otherwise `Thread::name` will trigger undefined behaviour. I've taken the opportunity to split out the unnamed thread case into a separate `new_unnamed` function to make the safety requirement clearer. All callers meet the safety requirement now that #123505 has been merged.
Doc: replace x with y for hexa-decimal fmt
I found it a bit unintuitive to know which is variable and which is the format string in `format!("{x:x}")`, so I switched it to `y`.
OpenBSD fix long socket addresses
Original diff from ``@notgull`` in #118349, small changes from me.
on OpenBSD, getsockname(2) returns the actual size of the socket address, and not the len of the content. Figure out the length for ourselves. see https://marc.info/?l=openbsd-bugs&m=170105481926736&w=2Fixes#116523
Thread local updates for idiomatic examples
Update thread local examples to make more idiomatic use of `Cell` for `Copy` types, `RefCell` for non-`Copy` types.
Also shrink the size of `unsafe` blocks, add `SAFETY` comments, and fix `clippy::redundant_closure_for_method_calls`.
Get rid of `USIZE_MARKER` in formatting infrastructure
An alternative to #123780.
The `USIZE_MARKER` function used to differentiate between placeholder and count arguments is never called anyway, so we can just replace the function-pointer-comparison hack with an `enum` and an `unreachable_unchecked`, hopefully without causing a regression.
CC `@RalfJung`
Update documentation of Path::to_path_buf and Path::ancestors
`Path::to_path_buf`
> Changes the example from using the qualified path of PathBuf with an import. This is what's done in all other Path/PathBuf examples and makes the code look a bit cleaner.
`Path::ancestors`
> If you take a quick glance at the documentation for Path::ancestors, the unwraps take the natural focus. Potentially indicating that ancestors might panic.
In the reworked version I've also moved the link with parent returning None and that the iterator will always yield &self to before the yield examples.
Feel free to cherry-pick the changes you like.
Avoid more NonNull-raw-NonNull roundtrips in Vec
r? the8472
The standard library in general has a lot of these round-trips from niched types to their raw innards and back. Such round-trips have overhead in debug builds since https://github.com/rust-lang/rust/pull/120594. I removed some such round-trips in that initial PR and I've been meaning to come back and hunt down more such examples (this is the last item on https://github.com/rust-lang/rust/issues/120848).
zkvm: fix path to cmath in zkvm module
I don't know why the original author decided to use relative paths.
I think it would be better to use `use crate::sys::cmath;`
The according issue can be found here https://github.com/risc0/risc0/issues/1647
Remove `sys_common::thread`
Part of #117276.
The stack size calculation isn't system-specific at all and can just live together with the rest of the spawn logic.
