Speed up bootstrap a little.
The bootstrap script was calling `cargo metadata` 3 times (or 6 with `-v`). This is a very expensive operation, and this attempts to avoid the extra calls. On my system, a simple command like `./x.py test -h -v` goes from about 3 seconds to 0.4.
An overview of the changes:
- Call `cargo metadata` only once with `--no-deps`. Optional dependencies are filtered in `in_tree_crates` (handling `profiler_builtins` and `rustc_codegen_llvm` which are driven by the config).
- Remove a duplicate call to `metadata::build` when using `-v`. I'm not sure why it was there, it looks like a mistake or vestigial from previous behavior.
- Remove check for `_shim`, I believe all the `_shim` crates are now gone.
- Remove check for `rustc_` and `*san` for `test::Crate::should_run`, these are no longer dependencies in the `test` tree.
- Use relative paths in `./x.py test -h -v` output.
- Some code cleanup (remove unnecessary `find_compiler_crates`, etc.).
- Show suite paths (`src/test/ui/...`) in `./x.py test -h -v` output.
- Some doc comments.
bootstrap/install.rs: support a nonexistent `prefix` in `x.py install`
PR #49778 introduced fs::canonicalize() which fails for a nonexistent path.
This is a surprise for someone used to GNU Autotools' configure which can create any necessary intermediate directories in prefix.
This change makes it run fs::create_dir_all() before canonicalize().
bootstrap: read config from $RUST_BOOTSTRAP_CONFIG
This PR modifies bootstrap so that `config.toml` is read first from `RUST_BOOTSTRAP_CONFIG`, then `--config` and finally `config.toml` in the current directory.
This is a subjective change, intended to improve the ergnomics when using "development shells" for rustc development (for example, using tools such as Nix) which set environment variables to ensure a reproducible environment (these development shells can then be version controlled, e.g. [my rustc shell](6b74a5c170/nix/shells/rustc.nix)). By optionally reading `config.toml` from an environment variable, a `config.toml` can be defined in the development shell and a path to it exposed in the `RUST_BOOTSTRAP_CONFIG` environment variable - avoiding the need to manually symlink the contents of this file to `config.toml` in the working directory.
Change how compiler-builtins gets many CGUs
This commit intends to fix an accidental regression from #70846. The
goal of #70846 was to build compiler-builtins with a maximal number of
CGUs to ensure that each module in the source corresponds to an object
file. This high degree of control for compiler-builtins is desirable to
ensure that there's at most one exported symbol per CGU, ideally
enabling compiler-builtins to not conflict with the system libgcc as
often.
In #70846, however, only part of the compiler understands that
compiler-builtins is built with many CGUs. The rest of the compiler
thinks it's building with `sess.codegen_units()`. Notably the
calculation of `sess.lto()` consults `sess.codegen_units()`, which when
there's only one CGU it disables ThinLTO. This means that
compiler-builtins is built without ThinLTO, which is quite harmful to
performance! This is the root of the cause from #73135 where intrinsics
were found to not be inlining trivial functions.
The fix applied in this commit is to remove the special-casing of
compiler-builtins in the compiler. Instead the build system is now
responsible for special-casing compiler-builtins. It doesn't know
exactly how many CGUs will be needed but it passes a large number that
is assumed to be much greater than the number of source-level modules
needed. After reading the various locations in the compiler source, this
seemed like the best solution rather than adding more and more special
casing in the compiler for compiler-builtins.
Closes#73135
compiletest: Add directives to detect sanitizer support
Add needs-sanitizer-{address,leak,memory,thread} directive indicating
that test requires target with support for specific sanitizer.
This is an addition to the existing needs-sanitizer-support directive
indicating that test requires a sanitizer runtime library.
The existing needs-sanitizer-support directive could be incorporated into the
new ones, but I decided to retain it, since it enables running sanitizer
codegen tests even when building of sanitizer runtime libraries is disabled.
first stage of implementing LLVM code coverage
This PR replaces #70680 (WIP toward LLVM Code Coverage for Rust) since I am re-implementing the Rust LLVM code coverage feature in a different part of the compiler (in MIR pass(es) vs AST).
This PR updates rustc with `-Zinstrument-coverage` option that injects the llvm intrinsic `instrprof.increment()` for code generation.
This initial version only injects counters at the top of each function, and does not yet implement the required coverage map.
Upcoming PRs will add the coverage map, and add more counters and/or counter expressions for each conditional code branch.
Rust compiler MCP https://github.com/rust-lang/compiler-team/issues/278
Relevant issue: #34701 - Implement support for LLVMs code coverage instrumentation
***[I put together some development notes here, under a separate branch.](cfa0b21d34/src/test/codegen/coverage-experiments/README-THIS-IS-TEMPORARY.md)***
Fix up autoderef when reborrowing
Currently `(f)()` and `f.call_mut()` behaves differently if expression `f` contains autoderef in it. This causes a weird error in #72225.
When `f` is type checked, `Deref` is used (this is expected as we can't yet determine if we should use `Fn` or `FnMut`). When subsequently we determine the actual trait to be used, when using the `f.call_mut()` syntax the `Deref` is patched to `DerefMut`, while for the `(f)()` syntax case it is not.
This PR replicates the fixup for the first case.
Fixes#72225Fixes#68590
Reduce pointer casts in Box::into_boxed_slice
We only need to cast the pointer once to change `Box<T>` to an array
`Box<[T; 1]>`, then we can let unsized coercion return `Box<[T]>`.
Add rust specific features to print target features
Fixes#71583
`crt-static` is a rust specific target feature that's absent from llvm feature table, adding it there so that it shows under `rustc --print target-features`.
Probably the most native implementation I could think of, would love to get feedback.
Ensure std benchmarks get tested.
This ensures that the std benchmarks don't break in the future. Currently they aren't compiled or tested on CI, so they can easily bitrot. Testing a benchmark runs it with one iteration. Adding these should only add a few seconds to CI.
Closes#54176Closes#61913
Remove const prop for indirects
This was only used by one mir-opt test and since it causes buggy behavior under `-Zmir-opt-level=2`, it seems like we should remove it.
This was split out from #71946.
Closes#72679Closes#72372Closes#72285
Create self-contained directory and move there some of external binaries/libs
One of the steps to reach design described in https://github.com/rust-lang/rust/issues/68887#issuecomment-633048380
This PR moves things around and allows link code to handle the new directory structure.
tag/niche terminology cleanup
The term "discriminant" was used in two ways throughout the compiler:
* every enum variant has a corresponding discriminant, that can be given explicitly with `Variant = N`.
* that discriminant is then encoded in memory to store which variant is active -- but this encoded form of the discriminant was also often called "discriminant", even though it is conceptually quite different (e.g., it can be smaller in size, or even use niche-filling).
After discussion with @eddyb, this renames the second term to "tag". The way the tag is encoded can be either `TagEncoding::Direct` (formerly `DiscriminantKind::Tag`) or `TagEncoding::Niche` (formerly `DiscrimianntKind::Niche`).
This finally resolves some long-standing confusion I had about the handling of variant indices and discriminants, which surfaced in https://github.com/rust-lang/rust/pull/72419.
(There is also a `DiscriminantKind` type in libcore, it remains unaffected. I think this corresponds to the discriminant, not the tag, so that seems all right.)
r? @eddyb
Added tooltip for should_panic code examples
This change adds a tooltip to the documentation for `should_panic` examples. It currently displays identically to `compile_fail` examples, save for the changed text. It may be helpful to change the color that this displays in to make it visually more clear what is going on, but I'm unsure if additional colors wouldn't just be distracting.
I brought this [up on internals](https://internals.rust-lang.org/t/indicating-that-an-example-is-should-panic-in-docs/12544) a few days ago, and there seemed to be a mild positive response to it.
Mention functions pointers in the documentation
Fixes#51615.
This mentions function pointers in the documentation for `core::mem::zeroed`, adding them to the list of types that are **always** wrong when zeroed, with `&T` and `&mut T`.
@rustbot modify labels: T-doc, C-enhancement, T-libs
Tweak "non-primitive cast" error
- Suggest borrowing expression if it would allow cast to work.
- Suggest using `<Type>::from(<expr>)` when appropriate.
- Minor tweak to `;` typo suggestion.
Partily address #47136.
Make new type param suggestion more targetted
Do not suggest new type param when encountering a missing type in an ADT
field with generic parameters.
Fix#72640.
Export `#[inline]` fns with extern indicators
In ancient history (#36280) we stopped `#[inline]` fns being codegened if they weren't used. However,
- #72944
- #72463
observe that when writing something like
```rust
#![crate_type = "cdylib"]
#[no_mangle]
#[inline]
pub extern "C" fn foo() {
// ...
}
```
we really _do_ want `foo` to be codegened. This change makes this the case.
Resolves#72944, resolves#72463 (and maybe some more)
Only highlight doc search results via mouseover if mouse has moved
## What happens
- Go to https://doc.rust-lang.org/stable/std/index.html
- Put your mouse cursor somewhere in the middle where search results will appear and then don't move the mouse
- Press 's' to focus the search box
- Type a query that brings up enough search results to go under where your mouse cursor is
- Press the down arrow
- The search result that is one below where your mouse cursor is will be highlighted.
## What I expected
When not currently using the mouse, I expect doing a search and then pressing the down arrow to always highlight the first search result immediately below the search box.
## The fix
This feels a bit hacky to me; I'm open to other solutions. This introduces a global JS var that keeps track of whether the person searching has moved their mouse after doing a search or not, and only uses the mouse position to highlight search results if the person HAS moved the mouse AFTER doing a search.
Complete the std::time documentation to warn about the inconsistencies between OS
Fixes#48980.
I put the new documentation in `src/libstd/time.rs` at the module-level because it affects all types, even the one that are not directly system dependents if they are used with affected types, but there may be a better place for it.
remove visit_terminator_kind from MIR visitor
For some reason, we had both `visit_terminator` and `visit_terminator_kind`. In contrast, for `Statement` we just have `visit_statement`. So this cleans things up by removing `visit_terminator_kind` and porting its users to `visit_terminator`.
Further tweak lifetime errors involving `dyn Trait` and `impl Trait` in return position
* Suggest substituting `'static` lifetime in impl/dyn `Trait + 'static` instead of `Trait + 'static + '_`
* When `'static` is explicit, also suggest constraining argument with it
* Reduce verbosity of suggestion message and mention lifetime in label
* Tweak output for overlapping required/captured spans
* Give these errors an error code
Follow up to #72543.
r? @nikomatsakis
Add tests for 'impl Default for [T; N]'
Related: #71690.
This pull request adds two tests:
- Even it T::default() panics, no leaks occur.
- [T; 0] is Default even if T is not.
I believe at some moment `Default` impl for arrays will be rewritten to use const generics instead of macros, and these tests will help to prevent behavior changes.
add raw_ref macros
In https://github.com/rust-lang/rust/issues/64490, various people were in favor of exposing `&raw` as a macro first before making the actual syntax stable. So this PR (unstably) introduces those macros.
I'll create the tracking issue if we're okay moving forward with this.
Improve diagnostics for `let x += 1`
Fixes(?) #66736
The code responsible for the `E0404` errors is [here](https://github.com/rust-lang/rust/blob/master/src/librustc_parse/parser/ty.rs#L399-L424) which I don't think can be easily modified to prevent emitting an error in one specific case. Because of this I couldn't get rid of `E0404` and instead added `E0067` along with a help message which will fix the problem.
r? @estebank
Make novel structural match violations not a `bug`
Fixes (on master) #73431.
Ideally, `CustomEq` would emit a strict subset of the structural match errors that are found by `search_for_structural_match_violation`, since it allows more cases due to value-based reasoning. However, const qualification is more conservative than `search_for_structural_match_violation` around associated constants, since qualification does not try to substitute type parameters.
In the long term, we should probably make const qualification work for generic associated constants, but I don't like extending its capabilities even further.
r? @pnkfelix
