make is_power_of_two a const function
This makes `is_power_of_two` a const function by using `&` instead of short-circuiting `&&`; Rust supports bitwise `&` for `bool` and short-circuiting is not required in the existing expression.
I don't think this needs a const-hack label as I don't find the changed code less readable, if anything I prefer that it is clearer that short circuiting is not used.
@oli-obk
Change untagged_unions to not allow union fields with drop
This is a rebase of #56440, massaged to solve merge conflicts and make the test suite pass.
Change untagged_unions to not allow union fields with drop
Union fields may now never have a type with attached destructor. This for example allows unions to use arbitrary field types only by wrapping them in `ManuallyDrop` (or similar).
The stable rule remains, that union fields must be `Copy`. We use the new rule for the `untagged_union` feature.
Tracking issue: https://github.com/rust-lang/rust/issues/55149
Fix `canonicalize_const_var` leaking inference variables
Fixes#61338Fixes#61516Fixes#62536Fixes#64087Fixes#64863Fixes#65623
I added regression tests for all these issues apart from #64863, which is very similar to #61338.
r? @varkor
[mir-opt] Improve SimplifyLocals pass so it can remove unused consts
The `ConstProp` can cause many locals to be initialized to a constant
value and then never read from. `ConstProp` can also evaluate ZSTs into
constant values. Previously, many of these would be removed by other
parts of the MIR optimization pipeline. However, evaluating ZSTs
(especially `()`) into constant values defeated those parts of the
optimizer and so in a2e3ed5, I added a
hack to `ConstProp` that skips evaluating ZSTs to avoid that regression.
This commit changes `SimplifyLocals` so that it doesn't consider writes
of const values to a local to be a use of that local. In doing so,
`SimplifyLocals` is able to remove otherwise unused locals left behind
by other optimization passes (`ConstProp` in particular).
r? @oli-obk
Correctly note code as Ok not error for E0573
Hi, this is my first pull request to the Rust project.
The fix is very small one just to fix an oversight in a comment.
Namely, [this documentation PR](https://github.com/rust-lang/rust/pull/65234) added a longer explanation for E0573. It illustrated the error using erroneous/corrected contrasting examples. But it accidentally forgot to remove `// error` from the corrected example.
Sadly, I found the error after the PR got merged. [As suggested by the original author](https://github.com/rust-lang/rust/pull/65234/files#r336518549) of the PR, I created an PR to fix this.
Part of #61137.
It's a full conversion, except in `DefKey::compute_stable_hash()` where
a `Symbol` now is converted to an `InternedString` before being hashed.
This was necessary to avoid test failures.
Check all files in `src/test` for `borrowck_graphviz_postflow`
This attribute causes DOT files to be generated in the top-level directory. It is intended to be used only temporarily and should never appear on master. This also tells git to ignore DOT files in the root or the `mir_dump` directory, which `-Z dump-mir` uses by default.
This will prevent #65071 from occurring again. It needs to be merged after #65629, otherwise `tidy` will start failing.
r? @Mark-Simulacrum
The `ConstProp` can cause many locals to be initialized to a constant
value and then never read from. `ConstProp` can also evaluate ZSTs into
constant values. Previously, many of these would be removed by other
parts of the MIR optimization pipeline. However, evaluating ZSTs
(especially `()`) into constant values defeated those parts of the
optimizer and so in a2e3ed5c05, I added a
hack to `ConstProp` that skips evaluating ZSTs to avoid that regression.
This commit changes `SimplifyLocals` so that it doesn't consider writes
of const values to a local to be a use of that local. In doing so,
`SimplifyLocals` is able to remove otherwise unused locals left behind
by other optimization passes (`ConstProp` in particular).
Rollup of 8 pull requests
Successful merges:
- #65314 (rustdoc: forward -Z options to rustc)
- #65592 (clarify const_prop ICE protection comment)
- #65603 (Avoid ICE when include! is used by stdin crate)
- #65614 (Improve error message for APIT with explicit generic arguments)
- #65629 (Remove `borrowck_graphviz_postflow` from test)
- #65633 (Remove leading :: from paths in doc examples)
- #65638 (Rename the default argument 'def' to 'default')
- #65639 (Fix parameter name in documentation)
Failed merges:
r? @ghost
Remove leading :: from paths in doc examples
Noted some pre-2018 path syntax in the doc examples, for example:
https://doc.rust-lang.org/std/process/fn.exit.html
```rust
fn main() {
::std::process::exit(match run_app() {
Ok(_) => 0,
...
```
Couldn't find an existing issue on this (then again, "::" makes for an annoying thing to search for) so if there is already something fixing this and/or there's a reason to not fix it, just close this PR.
(Also fixed indentation in the `process::exit()` docs)
Remove `borrowck_graphviz_postflow` from test
Resolves#65071 (again).
Sorry. I've added a commit hook to prevent this from happening in the future.
r? @petrochenkov
Avoid ICE when include! is used by stdin crate
This should hopefully also eliminate the ICE when using `include_bytes!`, `include_str!` and `#[doc(include = "...")]` with a stdio input.
I couldn't see a clear way to write a compile-fail test using compiletest with a stdio input, so I haven't written any tests for this change.
Fixes#63900
clarify const_prop ICE protection comment
This is based on discussion at https://github.com/rust-lang/rust/pull/64890/files#r334555787.
That said, why are function arguments the only unsized locals that could remain uninitialized? Couldn't we also fail to initialize some local but still go on with const_prop, and then hit a line that takes a reference to that? Cc @wesleywiser @oli-obk ; I don't know enough about const-prop to understand why this can happen only for function arguments.
~~The PR includes https://github.com/rust-lang/rust/pull/64890; the only new commit is 05e4e6ba0d5.~~
rustdoc: forward -Z options to rustc
Currently rustdoc does not forward `-Z` options to rustc when building
test executables. This makes impossible to use rustdoc to run test
samples when crate under test is instrumented with one of sanitizers
`-Zsanitizer=...`, since the final linking step will not include
sanitizer runtime library.
Forward `-Z` options to rustc to solve the issue.
Helps with #43031.
