In general, the I/O interface of hermit-abi is more POSIX-like
interface. Consequently, platform abstraction layer for HermitOS
has slightly adjusted and some inaccuracies remove.
Prevent copy-paste errors from producing new starved-for-resources
threaded platforms by raising `DEFAULT_MIN_STACK_SIZE` from 4096 bytes
to at least 64KiB.
Two platforms "affected" by this have no actual threads:
- UEFI
- "unsupported"
Platforms that this actually affects:
- wasm32-wasi with "atomics" enabled
- wasm32-wasi-p1-threads
Two exceptions:
- SGX: a "secure code execution" platform, stays at 4096B
- TEEOS: also a "secure code execution" platform, stays at 8192B
I believe either of these may have sufficiently "interesting" semantics
around threads, or significant external library support. Either would
mean making any choices here for them is suspect.
Rollup of 9 pull requests
Successful merges:
- #124840 (resolve: mark it undetermined if single import is not has any bindings)
- #125622 (Winnow private method candidates instead of assuming any candidate of the right name will apply)
- #125648 (Remove unused(?) `~/rustsrc` folder from docker script)
- #125672 (Add more ABI test cases to miri (RFC 3391))
- #125800 (Fix `mut` static task queue in SGX target)
- #125871 (Orphanck[old solver]: Consider opaque types to never cover type parameters)
- #125893 (Handle all GVN binops in a single place.)
- #126008 (Port `tests/run-make-fulldeps/issue-19371` to ui-fulldeps)
- #126032 (Update description of the `IsTerminal` example)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix `mut` static task queue in SGX target
[PR 125046](https://github.com/rust-lang/rust/pull/125046) prevents mutable references to statics with `#[linkage]`. Such a construct was used with the tests for the `x86_64-fortanix-unknown-sgx` target. This PR fixes this and cleans up code a bit in 5 steps. Each step passes CI:
- The `mut` static is removed, and `Task` explicitly implements `Send`
- Renaming of the `task_queue::lock` function
- Pass function for `Thread` as `Send` to `Thread::imp` and update when `Packet<'scope, T>` implements `Sync`
- Storing `Task::p` as a type that implements `Send`
- Letting the compiler auto implement `Send` for `Task`
cc: ``@jethrogb``
std::unix::fs::get_path: using fcntl codepath for netbsd instead.
on netbsd, procfs is not as central as on linux/solaris thus can be perfectly not mounted.
Thus using fcntl with F_GETPATH, the kernel deals with MAXPATHLEN internally too.
Add `size_of` and `size_of_val` and `align_of` and `align_of_val` to the prelude
(Note: need to update the PR to add `align_of` and `align_of_val`, and remove the second commit with the myriad changes to appease the lint.)
Many, many projects use `size_of` to get the size of a type. However,
it's also often equally easy to hardcode a size (e.g. `8` instead of
`size_of::<u64>()`). Minimizing friction in the use of `size_of` helps
ensure that people use it and make code more self-documenting.
The name `size_of` is unambiguous: the name alone, without any prefix or
path, is self-explanatory and unmistakeable for any other functionality.
Adding it to the prelude cannot produce any name conflicts, as any local
definition will silently shadow the one from the prelude. Thus, we don't
need to wait for a new edition prelude to add it.
Fix typo in the docs of `HashMap::raw_entry_mut`
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Explain differences between `{Once,Lazy}{Cell,Lock}` types
The question of "which once-ish cell-ish type should I use?" has been raised multiple times, and is especially important now that we have stabilized the `LazyCell` and `LazyLock` types. The answer for the `Lazy*` types is that you would be better off using them if you want to use what is by far the most common pattern: initialize it with a single nullary function that you would call at every `get_or_init` site. For everything else there's the `Once*` types.
"For everything else" is a somewhat weak motivation, as it only describes by negation. While contrasting them is inevitable, I feel positive motivations are more understandable. For this, I now offer a distinct example that helps explain why `OnceLock` can be useful, despite `LazyLock` existing: you can do some cool stuff with it that `LazyLock` simply can't support due to its mere definition.
The pair of `std::sync::*Lock`s are usable inside a `static`, and can serve roles in async or multithreaded (or asynchronously multithreaded) programs that `*Cell`s cannot. Because of this, they received most of my attention.
Fixes#124696Fixes#125615
Change pedantically incorrect OnceCell/OnceLock wording
While the semantic intent of a OnceCell/OnceLock is that it can only be written to once (upon init), the fact of the matter is that both these types offer a `take(&mut self) -> Option<T>` mechanism that, when successful, resets the cell to its initial state, thereby [technically allowing it to be written to again](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=415c023a6ae1ef35f371a2d3bb1aa735)
Despite the fact that this can only happen with a mutable reference (generally only used during the construction of the OnceCell/OnceLock), it would be incorrect to say that the type itself as a whole *categorically* prevents being initialized or written to more than once (since it is possible to imagine an identical type only without the `take()` method that actually fulfills that contract).
To clarify, change "that cannot be.." to "that nominally cannot.." and add a note to OnceCell about what can be done with an `&mut Self` reference.
```@rustbot``` label +A-rustdocs
Make TLS accessors closures that return pointers
The current TLS macros generate a function that returns an `Option<&'static T>`. This is both risky as we lie about lifetimes, and necessitates that those functions are `unsafe`. By returning a `*const T` instead, the accessor function do not have safety requirements any longer and can be made closures without hassle. This PR does exactly that!
For native TLS, the closure approach makes it trivial to select the right accessor function at compile-time, which could result in a slight speed-up (I have the hope that the accessors are now simple enough for the MIR-inliner to kick in).
on netbsd, procfs is not as central as on linux/solaris thus
can be perfectly not mounted.
Thus using fcntl with F_GETPATH, the kernel deals with MAXPATHLEN
internally too.
While slightly verbose, it helps explain "why bother with OnceLock?"
This is a point of confusion that has been raised multiple times
shortly before and after the stabilization of LazyLock.
This example is spiritually an example of LazyLock, as it computes a
variable at runtime but accepts no inputs into that process.
It is also slightly simpler and thus easier to understand.
Change it to an even-more concise version and move it to LazyLock.
The example now editorializes slightly more. This may be unnecessary,
but it can be educational for the reader.
std::pal::unix::thread fetching min stack size on netbsd.
PTHREAD_STACK_MIN is not defined however sysconf/_SC_THREAD_STACK_MIN returns it as it can vary from arch to another.
Make `std::env::{set_var, remove_var}` unsafe in edition 2024
Allow calling these functions without `unsafe` blocks in editions up until 2021, but don't trigger the `unused_unsafe` lint for `unsafe` blocks containing these functions.
Fixes#27970.
Fixes#90308.
CC #124866.
Allow calling these functions without `unsafe` blocks in editions up
until 2021, but don't trigger the `unused_unsafe` lint for `unsafe`
blocks containing these functions.
Fixes#27970.
Fixes#90308.
CC #124866.
Make more of the test suite run on Mac Catalyst
Combined with https://github.com/rust-lang/rust/pull/125225, the only failing parts of the test suite are in `tests/rustdoc-js`, `tests/rustdoc-js-std` and `tests/debuginfo`. Tested with:
```console
./x test --target=aarch64-apple-ios-macabi library/std
./x test --target=aarch64-apple-ios-macabi --skip=tests/rustdoc-js --skip=tests/rustdoc-js-std --skip=tests/debuginfo tests
```
Will probably put up a PR later to enable _running_ on (not just compiling for) Mac Catalyst in CI, though not sure where exactly I should do so? `src/ci/github-actions/jobs.yml`?
Note that I've deliberately _not_ enabled stack overflow handlers on iOS/tvOS/watchOS/visionOS (see https://github.com/rust-lang/rust/issues/25872), but rather just skipped those tests, as it uses quite a few APIs that I'd be weary about getting rejected by the App Store (note that Swift doesn't do it on those platforms either).
r? ``@workingjubilee``
CC ``@thomcc``
``@rustbot`` label O-ios O-apple
This adds the `only-apple`/`ignore-apple` compiletest directive, and
uses that basically everywhere instead of `only-macos`/`ignore-macos`.
Some of the updates in `run-make` are a bit redundant, as they use
`ignore-cross-compile` and won't run on iOS - but using Apple in these
is still more correct, so I've made that change anyhow.
Less syscalls for the `copy_file_range` probe
If it's obvious from the actual syscall results themselves that the syscall is supported or unsupported, don't do an extra syscall with an invalid file descriptor.
CC #122052
Panic if `PathBuf::set_extension` would add a path separator
This is likely never intended and potentially a security vulnerability if it happens.
I'd guess that it's mostly literal strings that are passed to this function in practice, so I'm guessing this doesn't break anyone.
CC #125060
While the semantic intent of a OnceCell/OnceLock is that it can only be written
to once (upon init), the fact of the matter is that both these types offer a
`take(&mut self) -> Option<T>` mechanism that, when successful, resets the cell
to its initial state, thereby technically allowing it to be written to again.
Despite the fact that this can only happen with a mutable reference (generally
only used during the construction of the OnceCell/OnceLock), it would be
incorrect to say that the type itself as a whole categorically prevents being
initialized or written to more than once (since it is possible to imagine an
identical type only without the `take()` method that actually fulfills that
contract).
To clarify, change "that cannot be.." to "that nominally cannot.." and add a
note to OnceCell about what can be done with an `&mut Self` reference.
Rollup of 6 pull requests
Successful merges:
- #125263 (rust-lld: fallback to rustc's sysroot if there's no path to the linker in the target sysroot)
- #125345 (rustc_codegen_llvm: add support for writing summary bitcode)
- #125362 (Actually use TAIT instead of emulating it)
- #125412 (Don't suggest adding the unexpected cfgs to the build-script it-self)
- #125445 (Migrate `run-make/rustdoc-with-short-out-dir-option` to `rmake.rs`)
- #125452 (Cleanup check-cfg handling in core and std)
r? `@ghost`
`@rustbot` modify labels: rollup
Cleanup check-cfg handling in core and std
Follow-up to https://github.com/rust-lang/rust/pull/125296 where we:
- expect any feature cfg in std, due to `#[path]` imports
- move some check-cfg args inside the `build.rs` as per Cargo recommendation
- and replace the fake Cargo feature `"restricted-std"` by the custom cfg `restricted_std`
Fixes https://github.com/rust-lang/rust/pull/125296#issuecomment-2127009301
r? `@bjorn3` (maybe, feel free to re-roll)
