Ignore `-C strip` on MSVC
tl;dr - Define `-Cstrip` to only ever affect the binary; no other build artifacts.
This is necessary to improve cross-platform behavior consistency: if someone wanted debug information to be contained only in separate files on all platforms, they would set `-Cstrip=symbols` and `-Csplit-debuginfo=packed`, but this would result in no PDB files on MSVC.
Resolves#114215
fix normalizing in different `ParamEnv`s with the same `InferCtxt`
This PR changes the key of the projection cache from just `AliasTy` to `(AliasTy, ParamEnv)` to allow normalizing in different `ParamEnv`s without resetting caches. Previously, normalizing the same alias in different param envs would always reuse the cached result from the first normalization, which is incorrect if the projection clauses in the param env have changed.
Fixing this bug allows us to get rid of `InferCtxt::clear_caches`, which was only used by the `AutoTraitFinder`, because it requires normalizing in different param envs.
r? `@fmease`
Fix trait solver overflow with `non_local_definitions` lint
This PR fixes the trait solver overflow with the `non_local_definitions` lint reported in https://github.com/rust-lang/rust/issues/123573 using the suggestion from `@lcnr:` https://github.com/rust-lang/rust/issues/123573#issuecomment-2041348320 to use the next trait solver.
~~I have not (yet) tried to create a minimized repro~~ ``@compiler-errors`` did the minimization (thanks you) but I have manually tested on the `starlark-rust` project that it fixes the issue.
Fixes#123573
r? `@lcnr`
Flip spans for precise capturing syntax not capturing a ty/const param, and for implicit captures of lifetime params
Make the primary span point to the opaque, rather than the param which might be very far away (e.g. in an impl header hundreds of lines above).
This handles using deref patterns to choose the correct match arm. This
does not handle bindings or guards.
Co-authored-by: Deadbeef <ent3rm4n@gmail.com>
Fix capturing duplicated lifetimes via parent in `precise_captures` (`impl use<'...>`)
For technical reasons related to the way that `Self` and `T::Assoc` are lowered from HIR -> `rustc_middle::ty`, an opaque may mention in its bounds both the original early-bound lifetime from the parent `impl`/`fn`, *and* the *duplicated* early-bound lifetime on the opaque.
This is fine -- and has been fine since `@cjgillot` rewrote the way we handled opaque lifetime captures, and we went further to allow this behavior explicitly in https://github.com/rust-lang/rust/pull/115659. It's worthwhile to read this PR's technical section to recall how this duplication works and when it acts surprisingly.
The problem here is that the check that make sure that `impl use<'a, 'b>` lists all of the opaque's captured lifetimes wasn't smart enough to consider both these captured lifetimes and the original lifetimes they're duplicated from to be equal. This PR fixes that.
r? oli-obk
Implement Modified Condition/Decision Coverage
This is an implementation based on llvm backend support (>= 18) by `@evodius96` and branch coverage support by `@Zalathar.`
### Major changes:
* Add -Zcoverage-options=mcdc as switch. Now coverage options accept either `no-branch`, `branch`, or `mcdc`. `mcdc` also enables `branch` because it is essential to work.
* Add coverage mapping for MCDCBranch and MCDCDecision. Note that MCDCParameter evolves from llvm 18 to llvm 19. The mapping in rust side mainly references to 19 and is casted to 18 types in llvm wrapper.
* Add wrapper for mcdc instrinc functions from llvm. And inject associated statements to mir.
* Add BcbMappingKind::Decision, I'm not sure is it proper but can't find a better way temporarily.
* Let coverage-dump support parsing MCDCBranch and MCDCDecision from llvm ir.
* Add simple tests to check whether mcdc works.
* Same as clang, currently rustc does not generate instrument for decision with more than 6 condtions or only 1 condition due to considerations of resource.
### Implementation Details
1. To get information about conditions and decisions, `MCDCState` in `BranchInfoBuilder` is used during hir lowering to mir. For expressions with logical op we call `Builder::visit_coverage_branch_operation` to record its sub conditions, generate condition ids for them and save their spans (to construct the span of whole decision). This process mainly references to the implementation in clang and is described in comments over `MCDCState::record_conditions`. Also true marks and false marks introduced by branch coverage are used to detect where the decision evaluation ends: the next id of the condition == 0.
2. Once the `MCDCState::decision_stack` popped all recorded conditions, we can ensure that the decision is checked over and push it into `decision_spans`. We do not manually insert decision span to avoid complexity from then_else_break in nested if scopes.
3. When constructing CoverageSpans, add condition info to BcbMappingKind::Branch and decision info to BcbMappingKind::Decision. If the branch mapping has non-zero condition id it will be transformed to MCDCBranch mapping and insert `CondBitmapUpdate` statements to its evaluated blocks. While decision bcb mapping will insert `TestVectorBitmapUpdate` in all its end blocks.
### Usage
```bash
echo "[build]\nprofiler=true" >> config.toml
./x build --stage 1
./x test tests/coverage/mcdc_if.rs
```
to build the compiler and run tests.
```shell
export PATH=path/to/llvm-build:$PATH
rustup toolchain link mcdc build/host/stage1
cargo +mcdc rustc --bin foo -- -Cinstrument-coverage -Zcoverage-options=mcdc
cd target/debug
LLVM_PROFILE_FILE="foo.profraw" ./foo
llvm-profdata merge -sparse foo.profraw -o foo.profdata
llvm-cov show ./foo -instr-profile=foo.profdata --show-mcdc
```
to check "foo" code.
### Problems to solve
For now decision mapping will insert statements to its all end blocks, which may be optimized by inserting a final block of the decision. To do this we must also trace the evaluated value at each end of the decision and join them separately.
This implementation is not heavily tested so there should be some unrevealed issues. We are going to check our rust products in the next. Please let me know if you had any suggestions or comments.
Don't repeatedly duplicate TAIT lifetimes for each subsequently nested TAIT
Make it so that nested TAITs inherit the lifetimes from their parent item, not their parent TAIT. This is because we don't need to re-duplicate lifetimes for nested TAITs over and over, since the only lifetimes they can capture are from the parent item anyways.
This mirrors how RPITs work. This is **not** a functional change that should be observable, since the whole point of duplicating lifetimes and marking the shadowed ones (and uncaptured ones) as bivariant is designed to *not* be observable.
r? oli-obk
Don't inline integer literals when they overflow - new attempt
Basically #116633 but I implemented the suggested changes.
Fixes#115423. Fixes#116631.
This is my first contribution to this repo so please let me know if I'm supposed to change something :)
Properly handle emojis as literal prefix in macros
Do not accept the following
```rust
macro_rules! lexes {($($_:tt)*) => {}}
lexes!(🐛"foo");
```
Before, invalid emoji identifiers were gated during parsing instead of lexing in all cases, but this didn't account for macro pre-expansion of literal prefixes.
Fix#123696.
Match ergonomics 2024: miscellaneous code cleanups
- Store `ByRef` instead of `BindingAnnotation` in `PatInfo`
- Rename `BindingAnnotation` to `BindingMode`
r? ``@Nadrieril``
cc #123076
``@rustbot`` label A-patterns
Delay interning errors to after validation
fixes https://github.com/rust-lang/rust/issues/122398fixes#122548
This improves diagnostics since validation errors are usually more helpful compared with interning errors that just make broad statements about the entire constant
r? `@RalfJung`
Codegen ZSTs without an allocation
This makes sure that &[] is equivalent to unsafe code (from_raw_parts(dangling, 0)). No new stable guarantee is intended about whether or not we do this, this is just an optimization.
This regressed in #67000 (no comments I can see about that regression in the PR, though it did change the test modified here). We had previously performed this optimization since #63635.
Remove libc from rust_get_test_int uses
`rust_test_helpers.c` has a few unfortunate signatures which have made some of our UI tests _technically_ need the `libc` crate. This is my attempt to evict the need of `libc` for `rust_get_test_int`.
I've deleted `tests/ui/abi/foreign/foreign-no-abi.rs` because the test was originally written to check that `native mod` will compile without an ABI specifier. `native mod` was removed years before 1.0 and the test hasn't checked for anything for a long time.
Delay span bug when `Self` kw resolves to `DefKind::{Mod,Trait}`
Catch the case where `kw::Self` is recovered in the parser and causes us to subsequently resolve `&self`'s implicit type to something that's not a type.
This check could be made more accurate, though I'm not sure how hard we have to try here.
Fixes#123988
This makes sure that &[] is just as efficient as indirecting through
unsafe code (from_raw_parts). No new stable guarantee is intended about
whether or not we do this, this is just an optimization.
Co-authored-by: Ralf Jung <post@ralfj.de>
Use `/* value */` as a placeholder
The expression `value` isn't a valid suggestion; let's use `/* value */` as a placeholder (which is also invalid) since it more clearly signals to the user that they need to fill it in with something meaningful. This parallels the suggestions we have in a couple other places, like arguments.
We could also print the type name instead of `/* value */`, especially if it's suggestable, but I don't care strongly about that.
Taint const qualifs if a static is referenced that didn't pass wfcheck
It is correct to only check the signature here, as the ICE is caused by `USE_WITH_ERROR` trying to allocate memory to store the result of `WITH_ERROR` before evaluating it.
fixes#123153
Stabilize checking of cfgs at compile-time: `--check-cfg` option
This PR stabilize the `--check-cfg` CLI option of `rustc` (and `rustdoc`) 🎉.
In particular this PR does two things:
1. it makes the `--check-cfg` option stable
2. and it moves the documentation to the stable books
FCP: https://github.com/rust-lang/rust/issues/82450#issuecomment-1965328542Resolves#82450
``@rustbot`` labels +S-blocked +F-check-cfg
r? ``@petrochenkov``
Implement syntax for `impl Trait` to specify its captures explicitly (`feature(precise_capturing)`)
Implements `impl use<'a, 'b, T, U> Sized` syntax that allows users to explicitly list the captured parameters for an opaque, rather than inferring it from the opaque's bounds (or capturing *all* lifetimes under 2024-edition capture rules). This allows us to exclude some implicit captures, so this syntax may be used as a migration strategy for changes due to #117587.
We represent this list of captured params as `PreciseCapturingArg` in AST and HIR, resolving them between `rustc_resolve` and `resolve_bound_vars`. Later on, we validate that the opaques only capture the parameters in this list.
We artificially limit the feature to *require* mentioning all type and const parameters, since we don't currently have support for non-lifetime bivariant generics. This can be relaxed in the future.
We also may need to limit this to require naming *all* lifetime parameters for RPITIT, since GATs have no variance. I have to investigate this. This can also be relaxed in the future.
r? `@oli-obk`
Tracking issue:
- https://github.com/rust-lang/rust/issues/123432
Trait predicates for types which have errors may still
evaluate to OK leading to downstream ICEs. Now we return
a selection error for such types in candidate assembly and
thereby prevent such issues
