normalize use of backticks/lowercase in compiler messages for librustc_mir
normalize use of backticks/lowercase in compiler messages for librustc_mir
https://github.com/rust-lang/rust/issues/60532
r? @alexreg
Miri engine: support extra function (pointer) values
We want to add basic support for `dlsym` in Miri (needed to run the latest version of `getrandom`). For that to work, `dlsym` needs to return *something* that can be stored in a function pointer and later called.
So we add a new `ExtraFnVal` type to the `Machine` trait, and enable Miri's memory to associate allocation IDs with such values, so that `create_fn_alloc` and `get_fn` can work on *both* `Instance` (this is used for "normal" function pointers) and `ExtraFnVal`.
Cc @oli-obk
rustc_target: avoid negative register counts in the SysV x86_64 ABI.
Because `needed_{int,sse}` and `{int,sse}_regs` were only used with integer literals, they were inferred to `i32` and `{int,sse}_regs` could therefore be negative.
There was a check which prevented that, but *only* for aggregate arguments, not scalars.
Fixes#62350.
r? @nagisa or @rkruppe
Remove `compile-pass` from compiletest
This is a part of #62277.
Removes `compile-pass` from compiletest (and modify some tests' annotations).
r? @Centril
Create async version of the dynamic-drop test
Some of the tests in dynamic-drop have been cut:
* The tests that are just simpler versions of other tests - these tests are already fairly slow due to all of the unwinding and async functions have more control flow paths than normal functions.
* The union test - it's for an unstable feature that has an RFC to remove it.
* The generator test - there aren't async generators yet.
* The tests that show values being leaked - these can be added once the issue is fixed.
r? @Centril
cc #62121 @cramertj
Implement another internal lints
cc #49509
This adds ~~two~~ one internal lint~~s~~:
1. LINT_PASS_IMPL_WITHOUT_MACRO: Make sure, that the `{declare,impl}_lint_pass` macro is used to implement lint passes. cc #59669
2. ~~USAGE_OF_TYCTXT_AND_SPAN_ARGS: item 2 on the list in #49509~~
~~With 2. I wasn't sure, if this lint should be applied everywhere. That means a careful review of 0955835 would be great. Also 73fb9b4 allows this lint on some functions. Should I also apply this lint there?~~
TODO (not directly relevant for review):
- [ ] https://github.com/rust-lang/rust/pull/59316#discussion_r280186517 (not sure yet, if this works or how to query for `rustc_private`, since it's not in [`Features`](https://doc.rust-lang.org/nightly/nightly-rustc/syntax/feature_gate/struct.Features.html) 🤔 cc @eddyb)
- [x] https://github.com/rust-lang/rust/pull/61735#discussion_r292389870
- [x] Check explicitly for the `{declare,impl}_lint_pass!` macros
r? @oli-obk
Break out of the correct number of scopes in loops
We were incorrectly breaking out of one too many drop scopes when
generating MIR for loops and breakable blocks, resulting in use after
free and associated borrow checker warnings.
This wasn't noticed because the scope that we're breaking out of twice
is only used for temporaries that are created for adjustments applied to
the loop. Since loops generally propagate coercions to the `break`
expressions, the only case we see this is when the type of the loop is a
smart pointer to a trait object.
Closes#62312
Improve error span for async type inference error
Fixes#62382
Previously, we would point at the spawn of the 'await' expression,
instead of the actual expression with an unknown type.
We were incorrectly breaking out of one too many drop scopes when
generating MIR for loops and breakable blocks, resulting in use after
free and associated borrow checker warnings.
This wasn't noticed because the scope that we're breaking out of twice
is only used for temporaries that are created for adjustments applied to
the loop. Since loops generally propagate coercions to the `break`
expressions, the only case we see this is when the type of the loop is a
smart pointer to a trait object.
Migrate `compile-pass` annotations to `build-pass`
This is a part of #62277.
As a first step, the `compile-pass` tests are migrated to `build-pass`.
r? @cramertj
cc @Centril
wfcheck: resolve the type-vars in `AdtField` types
Normalization can leave some type-vars unresolved in its return type.
Make sure to resolve them so we have an infcx-independent type that can
be used with `needs_drop`.
Fixes#61402.
Closes#62212 - this PR fixes the root cause.
std: Move a process test out of libstd
This commit moves a test out of libstd which is causing deadlocks on
musl on CI. Looks like the recent update in musl versions brings in some
internal updates to musl which makes `setgid` and `setuid` invalid to
call after a `fork` in a multithreaded program. The issue seen here is
that the child thread was attempting to grab a lock held by a
nonexistent thread, meaning that the child process simply deadlocked
causing the whole test to deadlock.
This commit moves the test to its own file with no threads which should
work.
generalize impl trait to permit multiple lifetime bounds
Generalizes the region solver to support "pick constraints". These have the form:
```
pick R0 from [R1..Rn]
```
where `R1..Rn` are called the "option regions". The idea is that `R0` must be equal to *some* region in the set `R1..Rn`. These constraints are then used to handle cases like this:
```rust
fn foo<'a, 'b>(...) -> impl Trait<'a, 'b> { .. }
```
The problem here is that every region R in the hidden type must be equal to *either* `'a` *or* `'b` (or `'static`) -- in the past, the only kinds of constraints we had were outlives constraints, and since `'a` and `'b` are unrelated, there was no outlives constraint we could issue that would enforce that (`R: 'a` and `R: 'b` are both too strict, for example). But now we can issue a pick constraint: `pick R from ['a, 'b]`.
In general, solving pick constraints is tricky. We integrate them into the solver as follows. In general, during the propagation phase, we are monotonically growing a set of inference regions. To handle a case like `pick R from [O...]`, where `O...` represents the option regions, we do the following:
- Look for all the *lower bounds* of the region R -- that is, every region LB such that `R: LB` must hold.
- Look for all the *upper bounds* of the region R -- that is, every region UB such that `UB: R` must hold.
- Let the *viable options* be each option region O such that `UB: O` and `O: LB` for each UB, LB bound.
- Find the *minimal viable option* M, where `O: M` holds for every option region O.
If there is such a *minimal viable option*, then we make `R: M`. (This may in turn influence other bits of inference.) If there is no minimal viable option, either because all options were eliminated or because none of the remaining options are minimal, we do nothing. Ultimately, if the pick constraint is not satisfied, an error is reported.
For this logic, we currently require that the option regions O are always lifetime parameters. To determine the bounds, we walk the various outlives edges that were otherwise introduced.
r? @matthewjasper
cc @cramertj
Fixes#56238
TODO:
- [ ] Error messages include region variable info sometimes, how to fix?
- [ ] Tests for bare `existential type` and other impl Trait usage
Stabilize support for Profile-guided Optimization
This PR makes profile-guided optimization available via the `-C profile-generate` / `-C profile-use` pair of commandline flags and adds end-user documentation for the feature to the [rustc book](https://doc.rust-lang.org/rustc/). The PR thus ticks the last two remaining checkboxes of the [stabilization tracking issue](https://github.com/rust-lang/rust/issues/59913).
From the tracking issue:
> Profile-guided optimization (PGO) is a common optimization technique for ahead-of-time compilers. It works by collecting data about a program's typical execution (e.g. probability of branches taken, typical runtime values of variables, etc) and then uses this information during program optimization for things like inlining decisions, machine code layout, or indirect call promotion.
If you are curious about how this can be used, there is a rendered version of the documentation this PR adds available [here](
https://github.com/michaelwoerister/rust/blob/stabilize-pgo/src/doc/rustc/src/profile-guided-optimization.md).
r? @alexcrichton
cc @rust-lang/compiler
