On `x86_64-pc-windows-msvc`, we often get backtraces which look like
this:
```
10: 0x7ff77e0e9be5 - std::panicking::rust_panic_with_hook
11: 0x7ff77e0e11b4 - std::sys_common::backtrace::__rust_begin_short_backtrace::h5769736bdb11136c
12: 0x7ff77e0e116f - std::sys_common::backtrace::__rust_end_short_backtrace::h61c7ecb1b55338ae
13: 0x7ff77e0f89dd - std::panicking::begin_panic::h8e60ef9f82a41805
14: 0x7ff77e0e108c - d
15: 0x7ff77e0e1069 - c
16: 0x7ff77e0e1059 - b
17: 0x7ff77e0e1049 - a
18: 0x7ff77e0e1039 - core::ptr::drop_in_place<std::rt::lang_start<()>::{{closure}}>::h1bfcd14d5e15ba81
19: 0x7ff77e0e1186 - std::sys_common::backtrace::__rust_begin_short_backtrace::h5769736bdb11136c
20: 0x7ff77e0e100c - std::rt::lang_start::{{closure}}::ha054184bbf9921e3
```
Notice that `__rust_begin_short_backtrace` appears on frame 11 before
`__rust_end_short_backtrace` on frame 12. This is because in typical
release binaries without debug symbols, dbghelp.dll, which we use to walk
and symbolize the stack, does not know where CGU internal functions
start or end and so the closure invoked by `__rust_end_short_backtrace`
is incorrectly described as `__rust_begin_short_backtrace` because it
happens to be near that symbol.
While that can obviously change, this has been happening quite
consistently since #75048. Since this is a very small change to the std
and the change makes sense by itself, I think this is worth doing.
This doesn't completely resolve the situation for release binaries on
Windows, since without debug symbols, the stack printed can still show
incorrect symbol names (this is why the test uses `#[no_mangle]`) but it
does slightly improve the situation in that you see the same backtrace
you would see with `RUST_BACKTRACE=full` or in a debugger (without the
uninteresting bits at the top and bottom).
I looked in stdlib and as @BurntSushi thought, `raw` is generally
used for raw pointers, or other hazardous kinds of thing. stdlib does
not have `into_parts` apart from the one I added to `IntoInnerError`.
I did an ad-hoc search of the rustdocs for my current game project
Otter, which includes quite a large number of dependencies.
`into_parts` seems heavily used for things quite like this.
So change this name.
Suggested-by: Andrew Gallant <jamslam@gmail.com>
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
I didn't notice the submodule, which means I failed to re-export this
to make it actually-public.
Reported-by: Andrew Gallant <jamslam@gmail.com>
Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
The compression caches currently don't have any dedicated functionality
that would benefit from being separated. Incorporating caches directly
into the symbol manger also avoids dynamic memory allocation.
The symbol mangler, which is often passed by value, is now slightly
larger. This aspect will be addressed by a follow-up commit.
Rename two lints to comply with our lint naming convention
self_named_constructor -> self_named_constructors
append_instead_of_extend -> extend_with_drain
We don't need to `register_renamed` those lints, since I'll backport them to beta, so the old names won't hit stable.
changelog: none
(I'll adapt the changelog before merging #7498)
Add #[track_caller] for some function in core::mem.
These functions can panic for some types. This makes the panic point to the code that calls e.g. mem::uninitialized(), instead of inside the definition of mem::uninitialized.
Make const panic!("..") work in Rust 2021.
During const eval, this replaces calls to core::panicking::panic_fmt and std::panicking::being_panic_fmt with a call to a new const fn: core::panicking::const_panic_fmt. That function uses fmt::Arguments::as_str() to get the str and calls panic_str with that instead.
panic!() invocations with formatting arguments are still not accepted, as the creation of such a fmt::Arguments cannot be done in constant functions right now.
r? `@RalfJung`
Create `QuerySideEffects` and use it for diagnostics
The code for saving and loading diagnostics during execution is generalized to handle a new `QuerySideEffects` struct. Currently, this struct just holds diagnostics - in a follow-up PR, I plan to add support for storing attriutes marked as used during query execution.
This is a pure refactor, with no intended behavior changes.
Remove unsound TrustedRandomAccess implementations
Removes the implementations that depend on the user-definable trait `Copy`.
Fixes#85873 in the most straightforward way.
<hr>
_Edit:_ This PR now contains additional trait infrastructure to avoid performance regressions around in-place collect, see the discussion in this thread starting from the codegen test failure at https://github.com/rust-lang/rust/pull/85874#issuecomment-872327577.
With this PR, `TrustedRandomAccess` gains additional documentation that specifically allows for and specifies the safety conditions around subtype coercions – those coercions can happen in safe Rust code with the `Zip` API’s usage of `TrustedRandomAccess`. This PR introduces a new supertrait of `TrustedRandomAccess`(currently named `TrustedRandomAccessNoCoerce`) that _doesn’t allow_ such coercions, which means it can be still be useful for optimizing cases such as in-place collect where no iterator is handed out to a user (who could do coercions) after a `get_unchecked` call; the benefit of the supertrait is that it doesn’t come with the additional safety conditions around supertraits either, so it can be implemented for more types than `TrustedRandomAccess`.
The `TrustedRandomAccess` implementations for `vec::IntoIter`, `vec_deque::IntoIter`, and `array::IntoIter` are removed as they don’t conform with the newly documented safety conditions, this way unsoundness is removed. But this PR in turn (re-)adds a `TrustedRandomAccessNoCoerce` implementation for `vec::IntoIter` to avoid performance regressions from stable in a case of in-place collecting of `Vec`s [the above-mentioned codegen test failure]. Re-introducing the (currently nightly+beta-only) impls for `VecDeque`’s and `[T; N]`’s iterators is technically possible, but goes beyond the scope of this PR (i.e. it can happen in a future PR).
The examples added in #60396 used a "clever" post-increment hack,
unrelated to the actual point of the examples. That hack was found
[confusing] in the users forum, and #81811 already changed the `Vec`
example to use a more direct iterator. This commit changes `String` and
`VecDeque` in the same way for consistency.
[confusing]: https://users.rust-lang.org/t/help-understand-strange-expression/62858
Rollup of 10 pull requests
Successful merges:
- #81050 (Stabilize core::task::ready!)
- #81363 (Remove P: Unpin bound on impl Future for Pin)
- #86839 (Add doc aliases to fs.rs)
- #87435 (fix example code for E0617)
- #87451 (Add support for tuple struct field documentation)
- #87491 (Integrate context into the memorial to Anna)
- #87521 (Add long explanation for E0498)
- #87527 (Don't run MIR unsafeck at all when using `-Zthir-unsafeck`)
- #87550 (Add `CI_ONLY_WHEN_CHANNEL` and run `x86_64-gnu-stable` only on nightly)
- #87565 (Use backticks when referring to `core::future::Ready` in panic message)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Integrate context into the memorial to Anna
This came up after I reviewed https://github.com/rust-lang/rust/pull/87298, but I didn't propose this in time before that PR was merged.
If y'all feel this is too much churn on the file, no worries, feel free to close, but I felt this was a more fitting integration of the memorial into the test suite.
CC ``@boringcactus.``
Add support for tuple struct field documentation
Fixes #42615.
This is #80320 updated to new codebase and with added tests.
Part of https://github.com/rust-lang/rust/issues/83255.
cc ```@camelid``` (since you were involved on the original PR).
r? ```@jyn514```
Remove P: Unpin bound on impl Future for Pin
We can safely produce a `Pin<&mut P::Target>` without moving out of the `Pin` by using `Pin::as_mut` directly.
The `Unpin` bound was originally added in #56939 following the recommendation of ``@withoutboats`` in https://github.com/rust-lang/rust/issues/55766#issue-378417538
That comment does not give explicit justification for why the bound should be added. The relevant context was:
> [ ] Remove `impl<P> Unpin for Pin<P>`
>
> This impl is not justified by our standard justification for unpin impls: there is no pointer direction between `Pin<P>` and `P`. Its usefulness is covered by the impls for pointers themselves.
>
> This futures impl (link to the impl changed in this PR) will need to change to add a `P: Unpin` bound.
The decision to remove the unconditional impl of `Unpin for Pin` is sound (these days there is just an auto-impl for when `P: Unpin`). But, I think the decision to also add the `Unpin` bound for `impl Future` may have been unnecessary. Or if that's not the case, I'd be very interested to have the argument for why written down somewhere. The bound _appears_ to not be needed, as demonstrated by the change requiring no unsafe code and by the existence of `Pin::as_mut`.
Stabilize core::task::ready!
_Tracking issue: https://github.com/rust-lang/rust/issues/70922_
This PR stabilizes the `task::ready!` macro. Similar to https://github.com/rust-lang/rust/pull/80886, this PR was waiting on https://github.com/rust-lang/rust/issues/74355 to be fixed.
The `task::ready!` API has existed in the futures ecosystem for several years, and was added on nightly last year in https://github.com/rust-lang/rust/pull/70817. The motivation for this macro is the same as it was back then: virtually every single manual future implementation makes use of this; so much so that it's one of the few things included in the [futures-core](https://docs.rs/futures-core/0.3.12/futures_core) library.
r? ``@tmandry``
cc/ ``@rust-lang/wg-async-foundations`` ``@rust-lang/libs``
## Example
```rust
use core::task::{Context, Poll};
use core::future::Future;
use core::pin::Pin;
async fn get_num() -> usize {
42
}
pub fn do_poll(cx: &mut Context<'_>) -> Poll<()> {
let mut f = get_num();
let f = unsafe { Pin::new_unchecked(&mut f) };
let num = ready!(f.poll(cx));
// ... use num
Poll::Ready(())
}
```
