This requires introducing a new internal type `RcUninit` (and
`ArcUninit`), which can own an `RcBox<T>` without requiring it to be
initialized, sized, or a slice. This is similar to `UniqueRc`, but
`UniqueRc` doesn't support the allocator parameter, and there is no
`UniqueArc`.
This trait allows cloning DSTs, but is unsafe to implement and use
because it writes to possibly-uninitialized memory which must be of the
correct size, and must initialize that memory.
It is only implemented for `T: Clone` and `[T] where T: Clone`, but
additional implementations could be provided for specific `dyn Trait`
or custom-DST types.
Bootstrap command refactoring: refactor `BootstrapCommand` (step 1)
This PR is a first step towards https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap.
It refactors `BoostrapCommand` to get it closer to a state where it is an actual command wrapper that can be routed through a central place of command execution, and also to make the distinction between printing output vs handling output programatically clearer (since now it's a mess).
The existing usages of `BootstrapCommand` are complicated primarily because of different ways of handling output. There are commands that:
1) Want to eagerly print stdout/stderr of the executed command, plus print an error message if the command fails (output mode `PrintAll`). Note that this error message attempts to print stdout/stderr of the command when `-v` is enabled, but that will always be empty, since this mode uses `.status()` and not `.output()`.
2) Want to eagerly print stdout/stderr of the executed command, but do not print any additional error message if it fails (output mode `PrintOutput`)
3) Want to capture stdout/stderr of the executed command, but print an error message if it fails (output mode `PrintFailure`). This means that the user wants to either ignore the output or handle it programatically, but that's not obvious from the name.
The difference between 1) and 2) (unless explicitly specified) is determined dynamically based on the bootstrap verbosity level.
It is very difficult for me to wrap my head around all these modes. I think that in a future PR, we should split these axes into e.g. this:
1) Do I want to handle the output programmatically or print it to the terminal? This should be a separate axis, true/false. (Note that "hiding the output" essentially just means saying that I handle it programmatically, and then I ignore the output).
2) Do I want to print a message if the command fails? Yes/No/Based on verbosity (which would be the default).
Then there is also the failure mode, but that is relatively simple to handle, the command execution will just shutdown bootstrap (either eagerly or late) when the command fails.
Note that this is just a first refactoring steps, there are a lot of other things to be done, so some things might not look "final" yet. The next steps are (not necessarily in this order):
- Remove `run` and `run_cmd` and implement everything in terms of `run_tracked` and rename `run_tracked` to `run`
- Implement the refactoring specified above (change how output modes work)
- Modify `BootstrapCmd` so that it stores `Command` instead of `&mut Command` and remove all the annoying `BootstrapCmd::from` by changing `Command::new` to `BootstrapCmd::new`
- Refactor the rest of command executions not currently using `BootstrapCmd` that can access Builder to use the correct output and failure modes. This will include passing Builder to additional places.
- Handle the most complex cases, such as output streaming. That will probably need to be handled separately.
- Refactor the rest of commands that cannot access builder (e.g. `Config::parse`) by introducing a new command context that will be passed to these places, and then stored in `Builder`. Move certain fields (such as `fail_fast`) from `Builder` to the command context.
- Handle the co-operation of `Builder`, `Build`, `Config` and command context. There are some fields and logic used during command execution that are distributed amongst `Builder/Build/Config`, so it will require some refactoring to make it work if the execution will happen on a separate place (in the command context).
- Refactor logging of commands, so that it is either logged to a file or printed in a nice hierarchical way that cooperates with the `Step` debug hierarchical output.
- Implement profiling of commands (add command durations to the command log, print a log of slowest commands and their execution counts at the end of bootstrap execution, perhaps store command executions to `metrics.json`).
- Implement caching of commands.
- Implement testing of commands through snapshot tests/mocking.
Best reviewed commit by commit.
r? ``@onur-ozkan``
Fix `...` in multline code-skips in suggestions
When we have long code skips, we write `...` in the line number gutter.
For suggestions, we were "centering" the `...` with the line, but that was inconsistent with what we do in every other case *and* off-center.
Add `f16` inline ASM support for 32-bit ARM
Adds `f16` inline ASM support for 32-bit ARM. SIMD vector types are taken from [here](https://developer.arm.com/architectures/instruction-sets/intrinsics/#f:`@navigationhierarchiesreturnbasetype=[float]&f:@navigationhierarchieselementbitsize=[16]&f:@navigationhierarchiesarchitectures=[A32]).`
Relevant issue: #125398
Tracking issue: #116909
`@rustbot` label +F-f16_and_f128
Stop using `unlikely` in `strict_*` methods
The `strict_*` methods don't need (un)likely, because the `overflow_panic` calls are all `#[cold]`, [meaning](https://llvm.org/docs/LangRef.html#function-attributes) that LLVM knows any branch to them is unlikely without us needing to say so.
r? libs
Added an associated `const THIS_IMPLEMENTATION_HAS_BEEN_TRIPLE_CHECKED`
to the `StableOrd` trait to ensure that implementors carefully consider
whether the trait's contract is upheld, as incorrect implementations can
cause miscompilations.
Rollup of 7 pull requests
Successful merges:
- #126530 (Add `f16` inline ASM support for RISC-V)
- #126712 (Migrate `relocation-model`, `error-writing-dependencies` and `crate-name-priority` `run-make` tests to rmake)
- #126722 (Add method to get `FnAbi` of function pointer)
- #126787 (Add direct accessors for memory addresses in `Machine` (for Miri))
- #126798 ([fuchsia-test-runner] Remove usage of kw_only)
- #126809 (Remove stray `.` from error message)
- #126811 (Add a tidy rule to check that fluent messages and attrs don't end in `.`)
r? `@ghost`
`@rustbot` modify labels: rollup
Add a tidy rule to check that fluent messages and attrs don't end in `.`
This adds a new dependency on `fluent-parse` to `tidy` -- we already rely on it in rustc so I feel like it's not that big of a deal.
This PR also adjusts many error messages that currently end in `.`; not all of them since I added an `ALLOWLIST`, excluded `rustc_codegen_*` ftl files, and `.teach_note` attributes.
r? ``@estebank`` ``@oli-obk``
Migrate `relocation-model`, `error-writing-dependencies` and `crate-name-priority` `run-make` tests to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
Needs MSVC try-job due to #28026, almost guaranteed to fail, but let's see anyways.
try-job: aarch64-gnu
`/* try-job: x86_64-msvc */`
try-job: x86_64-apple-1
try-job: armhf-gnu
try-job: test-various
Add `f16` inline ASM support for RISC-V
This PR adds `f16` inline ASM support for RISC-V. A `FIXME` is left for `f128` support as LLVM does not support the required `Q` (Quad-Precision Floating-Point) extension yet.
Relevant issue: #125398
Tracking issue: #116909
`@rustbot` label +F-f16_and_f128
Add PidFd::{kill, wait, try_wait}
#117957 changed `Child` kill/wait/try_wait to use its pidfd instead of the pid, when one is available.
This PR extracts those implementations and makes them available on `PidFd` directly.
The `PidFd` implementations differ significantly from the corresponding `Child` methods:
* the methods can be called after the child has been reaped, which will result in an error but will be safe. This state is not observable in `Child` unless something stole the zombie child
* the `ExitStatus` is not kept, meaning that only the first time a wait succeeds it will be returned
* `wait` does not close stdin
* `wait` only requires `&self` instead of `&mut self` since there is no state to maintain and subsequent calls are safe
Tracking issue: #82971
These things don't need to be `Vec`s; boxed slices are enough.
The frequent one here is call arguments, but MIR building knows the number of arguments from the THIR, so the collect is always getting the allocation right in the first place, and thus this shouldn't ever add the shrink-in-place overhead.
As long as a pidfd is on a child it can be safely reaped. Taking it
would mean the child would now have to be awaited through its pid, but could also
be awaited through the pidfd. This could then suffer from a recycling race.
