Use ManuallyDrop in BufWriter::into_parts
The fact that `mem::forget` takes by value means that it interacts very poorly with Stacked Borrows; generally users think of calling it as a no-op, but in Stacked Borrows, the field retagging tends to cause surprise tag invalidation.
Clear `inner_attr_ranges` regularly.
There's a comment saying we don't do it for performance reasons, but it doesn't actually affect performance.
The commit also tweaks the control flow, to make clearer that two code paths are mutually exclusive.
r? ````@petrochenkov````
use "bootstrap" instead of "rustbuild" in comments and docs
Let's stick with the single name "bootstrap" to refer to the bootstrap project to avoid confusion. This should make it clearer, especially for new contributors.
Add FileCheck annotations to mir-opt/dest-prop tests
Part of https://github.com/rust-lang/rust/issues/116971, adds FileCheck annotations to MIR-opt tests in tests/mir-opt/dest-prop.
I would like some feedback. Also, I don't know how to approach `union.rs`. I couldn't figure out what it is testing.
r? cjgillot
using correct tool mode for `run-make-support` crate
We don't need to ensure std (and rustc) for testing run-make-support's unit tests. Using stage 0 compiler is already enough and speeds up `x test run-make-support` invocations on a clean build.
Remove memory leaks in doctests in `core`, `alloc`, and `std`
cc `@RalfJung` https://github.com/rust-lang/rust/issues/126067https://github.com/rust-lang/miri/issues/3670
Should be no actual *documentation* changes[^1], all added/modified lines in the doctests are hidden with `#`,
This PR splits the existing memory leaks in doctests in `core`, `alloc`, and `std` into two general categories:
1. "Non-focused" memory leaks that are incidental to the thing being documented, and/or are easy to remove, i.e. they are only there because preventing the leak would make the doctest less clear and/or concise.
- These doctests simply have a comment like `# // Prevent leaks for Miri.` above the added line that removes the memory leak.
- [^2]Some of these would perhaps be better as part of the public documentation part of the doctest, to clarify that a memory leak can happen if it is not otherwise mentioned explicitly in the documentation (specifically the ones in `(A)Rc::increment_strong_count(_in)`).
2. "Focused" memory leaks that are intentional and documented, and/or are possibly fragile to remove.
- These doctests have a `# // FIXME` comment above the line that removes the memory leak, with a note that once `-Zmiri-disable-leak-check` can be applied at test granularity, these tests should be "un-unleakified" and have `-Zmiri-disable-leak-check` enabled.
- Some of these are possibly fragile (e.g. unleaking the result of `Vec::leak`) and thus should definitely not be made part of the documentation.
This should be all of the leaks currently in `core` and `alloc`. I only found one leak in `std`, and it was in the first category (excluding the modules `@RalfJung` mentioned in https://github.com/rust-lang/rust/issues/126067 , and reducing the number of iterations of [one test](https://github.com/rust-lang/rust/blob/master/library/std/src/sync/once_lock.rs#L49-L94) from 1000 to 10)
[^1]: assuming [^2] is not added
[^2]: backlink
Windows: Add experimental support for linking std-required system DLLs using raw-dylib
For Windows, this allows std to define system imports without needing the user to have import libraries. It's intended for this to become the default.
For now it's an experimental feature so it can be tested using build-std.
Stabilize const unchecked conversion from u32 to char
Closes https://github.com/rust-lang/rust/issues/89259.
The functions in this PR were left out of the initial set of `feature(const_char_convert)` stabilizations in https://github.com/rust-lang/rust/pull/102470, but have since been unblocked by https://github.com/rust-lang/rust/pull/118979.
If `unsafe { from_u32_unchecked(u) }` is called in const with a value for which `from_u32(u)` returns None, we get the following compile error.
```rust
fn main() {
let _ = const { unsafe { char::from_u32_unchecked(0xd800) } };
}
```
```console
error[E0080]: it is undefined behavior to use this value
--> src/main.rs:2:19
|
2 | let _ = const { unsafe { char::from_u32_unchecked(0xd800) } };
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value: encountered 0x0000d800, but expected a valid unicode scalar value (in `0..=0x10FFFF` but not in `0xD800..=0xDFFF`)
|
= note: The rules on what exactly is undefined behavior aren't clear, so this check might be overzealous. Please open an issue on the rustc repository if you believe it should not be considered undefined behavior.
= note: the raw bytes of the constant (size: 4, align: 4) {
00 d8 00 00 │ ....
}
note: erroneous constant encountered
--> src/main.rs:2:13
|
2 | let _ = const { unsafe { char::from_u32_unchecked(0xd800) } };
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
```
We don't need to ensure std (and rustc) for testing run-make-support's
unit tests. Using stage 0 compiler is already enough and speeds up
`x test run-make-support` invocations on a clean build.
Signed-off-by: onur-ozkan <work@onurozkan.dev>
std::unix::fs: removing, now useless, layers predating macOs 10.10.
fdopendir, openat and unlinkat are available since yosemite but we support sierra as minimum.
Bootstrap command refactoring: improve debuggability (step 5)
Continuation of https://github.com/rust-lang/rust/pull/127321.
This PR improves the debuggability of command execution, by improving the output logged when a command fails (it now includes the exact location where the command was created and where it was executed), and also by adding a "drop bomb", which will panic if a command was created, but not executed (which is probably a bug).
Here is how the output of a failed command looks like:
```
Command "git" "foo" "[bar]" (failure_mode=Exit, stdout_mode=Capture, stderr_mode=Capture) did not execute successfully.
Expected success, got exit status: 1
Created at: src/core/build_steps/compile.rs:1699:9
Executed at: src/core/build_steps/compile.rs:1699:58
STDOUT ----
STDERR ----
git: 'foo' is not a git command. See 'git --help'.
```
And this is what is printed if you forget to execute a command:
```
thread 'main' panicked at /projects/personal/rust/rust/src/tools/build_helper/src/drop_bomb/mod.rs:42:13:
command constructed at `src/core/build_steps/compile.rs:1699:9` was dropped without being executed: `git`
```
Best reviewed commit by commit.
Tracking issue: https://github.com/rust-lang/rust/issues/126819
r? `@onur-ozkan`
Improved slice documentation
Improve slice documentation to include assert_eq checks for all the cases where there were existing examples. I think it makes things more clear when the documentation explicitly checks against values and shows the reader what it does.
I also started a rust internals discussion about it here: https://internals.rust-lang.org/t/improve-slice-documentaion/21168
Fix incorrect NDEBUG handling in LLVM bindings
We currently compile our LLVM bindings using `-DNDEBUG` if debuginfo for LLVM is disabled. However, `NDEBUG` doesn't have any relation to debuginfo, it controls whether assertions are enabled.
Split the LLVM_NDEBUG environment variable into two, so that assertions and debuginfo are controlled independently.
After this change, `LLVMRustDIBuilderInsertDeclareAtEnd` triggers an assertion failure on LLVM 19 due to an incorrect cast. Fix it by removing the unused return value entirely.
r? `@cuviper`
fix interleaved output in the default panic hook when multiple threads panic simultaneously
previously, we only held a lock for printing the backtrace itself. since all threads were printing to the same file descriptor, that meant random output in the default panic hook from one thread would be interleaved with the backtrace from another. now, we hold the lock for the full duration of the hook, and the output is ordered.
---
i noticed some odd things while working on this you may or may not already be aware of.
- libbacktrace is included as a submodule instead of a normal rustc crate, and as a result uses `cfg(backtrace_in_std)` instead of a more normal `cfg(feature = "rustc-dep-of-std")`. probably this is left over from before rust used a cargo-based build system?
- the default panic handler uses `trace_unsynchronized`, etc, in `sys::backtrace::print`. as a result, the lock only applies to concurrent *panic handlers*, not concurrent *threads*. in other words, if another, non-panicking, thread tried to print a backtrace at the same time as the panic handler, we may have UB, especially on windows.
- we have the option of changing backtrace to enable locking when `backtrace_in_std` is set so we can reuse their lock instead of trying to add our own.
Guard against calling `libc::exit` multiple times on Linux.
Mitigates (but does not fix) #126600 by ensuring only one thread which calls Rust `exit` actually calls `libc::exit`, and all other callers of Rust `exit` block.
Rollup of 11 pull requests
Successful merges:
- #126502 (Ignore allocation bytes in some mir-opt tests)
- #126922 (add lint for inline asm labels that look like binary)
- #127209 (Added the `xop` target-feature and the `xop_target_feature` feature gate)
- #127310 (Fix import suggestion ice)
- #127338 (Migrate `extra-filename-with-temp-outputs` and `issue-85019-moved-src-dir` `run-make` tests to rmake)
- #127381 (Migrate `issue-83045`, `rustc-macro-dep-files` and `env-dep-info` `run-make` tests to rmake)
- #127535 (Fire unsafe_code lint on unsafe extern blocks)
- #127619 (Suggest using precise capturing for hidden type that captures region)
- #127631 (Remove `fully_normalize`)
- #127632 (Implement `precise_capturing` support for rustdoc)
- #127660 (Rename the internal `const_strlen` to just `strlen`)
r? `@ghost`
`@rustbot` modify labels: rollup
Rename the internal `const_strlen` to just `strlen`
Since the libs and lang teams completed an FCP to allow for const `strlen` ([1]), currently implemented with `const_eval_select`, there is no longer any reason to avoid this specific function or use it only in const.
Rename it to reflect this status change.
[1]: https://github.com/rust-lang/rust/issues/113219#issuecomment-2016939401
Implement `precise_capturing` support for rustdoc
Implements rustdoc (+json) support for local (i.e. non-cross-crate-inlined) RPITs with `use<...>` precise capturing syntax.
Tests kinda suck. They're really hard to write 😰
r? `@fmease` or re-roll if you're too busy!
also cc `@aDotInTheVoid` for the json side
Tracking:
* https://github.com/rust-lang/rust/issues/127228#issuecomment-2201443216 (not fully fixed for cross-crate-inlined opaques)
* https://github.com/rust-lang/rust/issues/123432
Suggest using precise capturing for hidden type that captures region
Adjusts the "add `+ '_`" suggestion for opaques to instead suggest adding or reusing the `+ use<>` in the opaque.
r? oli-obk or please re-roll if you're busy!
Migrate `extra-filename-with-temp-outputs` and `issue-85019-moved-src-dir` `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).
Please try:
try-job: armhf-gnu
// try-job: test-various // already tried
try-job: x86_64-msvc
try-job: aarch64-apple
Fix import suggestion ice
Fixes#127302#127302 only crash in edition 2015
#120074 can only reproduced in edition 2021
so I added revisions in test file.
Added the `xop` target-feature and the `xop_target_feature` feature gate
This is an effort towards #127208. This adds the `xop` target feature gated by `xop_target_feature`.
add lint for inline asm labels that look like binary
fixes#94426
Due to a bug/feature in LLVM, labels composed of only the digits `0` and `1` can sometimes be confused with binary literals, even if a binary literal would not be valid in that position.
This PR adds detection for such labels and also as a drive-by change, adds a note to cases such as `asm!(include_str!("file"))` that the label that it found came from an expansion of a macro, it wasn't found in the source code.
I expect this PR to upset some people that were using labels `0:` or `1:` without issue because they never hit the case where LLVM got it wrong, but adding a heuristic to the lint to prevent this is not feasible - it would involve writing a whole assembly parser for every target that we have assembly support for.
[zulip discussion](https://rust-lang.zulipchat.com/#narrow/stream/238009-t-compiler.2Fmeetings/topic/.5Bweekly.5D.202024-06-20/near/445870628)
r? ``@estebank``
