Check if TCS is a null pointer on SGX
The `EENTER` instruction only checks if the TCS is aligned, not if it zero. Saying the address returned is a `NonNull<u8>` (for which `Tcs` is a type alias) is unsound. As well-behaved runners will not put the TCS at address zero, so the definition of `Tcs` is correct. However, `std` should check the address before casting it to a `NonNull`.
ping `@jethrogb` `@raoulstrackx`
`@rustbot` label I-unsound
Remove &[T] from vec_deque::Drain
Fixes https://github.com/rust-lang/rust/issues/60076
I don't know what the right approach is here. There were a few suggestions in the issue, and they all seem a bit thorny to implement. So I just picked one that was kind of familiar.
Optimize thread parking on NetBSD
As the futex syscall is not present in the latest stable release, NetBSD cannot use the efficient thread parker and locks Linux uses. Currently, it therefore relies on a pthread-based parker, consisting of a mutex and semaphore which protect a state variable. NetBSD however has more efficient syscalls available: [`_lwp_park`](https://man.netbsd.org/_lwp_park.2) and [`_lwp_unpark`](https://man.netbsd.org/_lwp_unpark.2). These already provide the exact semantics of `thread::park` and `Thread::unpark`, but work with thread ids. In `std`, this ID is here stored in an atomic state variable, which is also used to optimize cases were the parking token is already available at the time `thread::park` is called.
r? `@m-ou-se`
The `<*const T>::guaranteed_*` methods now return an option for the unknown case
cc https://github.com/rust-lang/rust/issues/53020#issuecomment-1236932443
I chose `0` for "not equal" and `1` for "equal" and left `2` for the unknown case so backends can just forward to raw pointer equality and it works ✨
r? `@fee1-dead` or `@lcnr`
cc `@rust-lang/wg-const-eval`
Rollup of 5 pull requests
Successful merges:
- #101366 (Restore old behaviour on broken UNC paths)
- #101492 (Suggest adding array lengths to references to arrays if possible)
- #101529 (Fix the example code and doctest for Formatter::sign_plus)
- #101573 (update `ParamKindOrd`)
- #101612 (Fix code generation of `Rvalue::Repeat` with 128 bit values)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Fix the example code and doctest for Formatter::sign_plus
The provided example to the `sign_plus` method on `fmt` was broken, it displays the `-` sign twice for negative numbers.
This pull request should fix the issue by `.abs()` ing the number so that the negative sign appears only once. It is just one possible solution to the issue, not sure if it's the best. However, this one will behave as expected when combined with fill and alignment operators.
Restore old behaviour on broken UNC paths
This fixes#101358 by restoring the behaviour from previous stable Rust versions. I'm not convinced this is ultimately right but I think it's less wrong and maybe this should be backported to beta?
r? libs
Fix the example code and doctest for Formatter::sign_plus
The provided example to the `sign_plus` method on `fmt` was broken, it displays the `-` sign twice for negative numbers.
This pull request should fix the issue by `.abs()` ing the number so that the negative sign appears only once. It is just one possible solution to the issue, not sure if it's the best. However, this one will behave as expected when combined with fill and alignment operators.
Compile spin_loop_hint as pause on x86 even without sse2 enabled
The x86 `pause` instruction was introduced with sse2, but because it is encoded as `rep nop`, it works just fine on cpu's without sse2 support. It just doesn't do anything.
Tweak future opaque ty pretty printing
1. The `Return` type of a generator doesn't need to be a lang item just for diagnostic printing of types
2. We shouldn't suppress the `Output = Ty` of a opaque future if the type is a int or float var.
Reimplement `carrying_add` and `borrowing_sub` for signed integers.
As per the discussion in #85532, this PR reimplements `carrying_add` and `borrowing_sub` for signed integers.
It also adds unit tests for both unsigned and signed integers, emphasing on the behaviours of the methods.
Open a BCrypt algorithm handle
Fixes#101474, supplants #101456.
Replaces use of a pseduo handle with manually opening a algorithm handle.
Most interesting thing here is the atomics.
r? `@thomcc`
Printing to stdio/stderr that have been opened with non-blocking
(O_NONBLOCK in linux) can result in an error, which is not handled
by std::io module causing a panic.
Signed-off-by: Usama Arif <usama.arif@bytedance.com>
The x86 `pause` instruction was introduced with sse2, but because it is encoded as `rep nop`, it works just fine on cpu's without sse2 support. It just doesn't do anything.
Document eager evaluation of `bool::then_some` argument
I encountered this earlier today and thought maybe `bool::then_some` could use a little addition to the documentation.
It's pretty obvious with familiarity and from looking at the implementation, but the argument for `then_some` is eagerly evaluated, which means if you do the following (as I did), you can have a problem:
```rust
// Oops!
let _ = something
.has_another_thing()
.then_some(something.another_thing_or_panic());
```
A note, similar to other methods with eagerly-evaluated arguments and a lazy alternative (`Option::or`, for example), could help point this out to people who forget (like me)!
Don't duplicate file descriptors into stdio fds
Ensures that file descriptors are never duplicated into the stdio fds even if a stdio fd has been closed.
Rollup of 6 pull requests
Successful merges:
- #101142 (Improve HIR stats)
- #101367 (Suggest `{Option,Result}::{copied,clone}()` to satisfy type mismatch)
- #101391 (more clippy::perf fixes)
- #101409 (Don't fire `rust_2021_incompatible_closure_captures` in `edition = 2021` crates)
- #101420 (Fix `hir::Local` doc to match with the variable name used: `init`)
- #101429 (Don't suggest reborrow if usage is inside a closure)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
proc_macro/bridge: use the cross-thread executor for nested proc-macros
While working on some other changes in the bridge, I noticed that when
running a nested proc-macro (which is currently only possible using
the unstable `TokenStream::expand_expr`), any symbols held by the
proc-macro client would be invalidated, as the same thread would be used
for the nested macro by default, and the interner doesn't handle nested
use.
After discussing with `@eddyb,` we decided the best approach might be to
force the use of the cross-thread executor for nested invocations, as it
will never re-use thread-local storage, avoiding the issue. This
shouldn't impact performance, as expand_expr is still unstable, and
infrequently used.
This was chosen rather than making the client symbol interner handle
nested invocations, as that would require replacing the internal
interner `Vec` with a `BTreeMap` (as valid symbol id ranges could now be
disjoint), and the symbol interner is known to be fairly perf-sensitive.
This patch adds checks to the execution strategy to use the cross-thread
executor when doing nested invocations. An alternative implementation
strategy could be to track this information in the `ExtCtxt`, however a
thread-local in the `proc_macro` crate was chosen to add an assertion so
that `rust-analyzer` is aware of the issue if it implements
`expand_expr` in the future.
r? `@eddyb`
Make `const_eval_select` a real intrinsic
This fixes issues where `track_caller` functions do not have nice panic
messages anymore when there is a call to the function, and uses the
MIR system to replace the call instead of dispatching via lang items.
Fixes#100696.
Make `ReentrantMutex` movable and `const`
As `MovableMutex` is now `const`, it can be used to simplify the implementation and interface of the internal reentrant mutex type. Consequently, the standard error stream does not need to be wrapped in `OnceLock` and `OnceLock::get_or_init_pin()` can be removed.
