Fuchsia explicitly builds rust and all rust targets with `-C
panic=abort` to minimize code generation size. However, when compiling a
proc-macro with this setting it can cause a warning to be emitted, which
breaks `tests/ui/invalid-compile-flags/crate-type-flag.rs`. This hasn't
been a problem in the past for us since we compile our proc macros on
host, rather than inside Fuchsia.
This attempts to fix the issue by explicitly requiring that we're using
the unwinder when compiling this test to avoid the warning being
emitted.
Fixes#135223
Exhaustively handle expressions in patterns
We currently have this invariant in HIR that a `PatKind::Lit` or a `PatKind::Range` only contains
* `ExprKind::Lit`
* `ExprKind::UnOp(Neg, ExprKind::Lit)`
* `ExprKind::Path`
* `ExprKind::ConstBlock`
So I made `PatKind::Lit` and `PatKind::Range` stop containing `Expr`, and instead created a `PatLit` type whose `kind` enum only contains those variants.
The only place code got more complicated was in clippy, as it couldn't share as much anymore with `Expr` handling
It may be interesting on merging `ExprKind::{Path,Lit,ConstBlock}` in the future and using the same `PatLit` type (under a new name).
Then it should also be easier to eliminate any and all `UnOp(Neg, Lit) | Lit` matching that we have across the compiler. Some day we should fold the negation into the literal itself and just store it on the numeric literals
`best_blame_constraint`: Blame better constraints when the region graph has cycles from invariance or `'static`
This fixes#132749 by changing which constraint is blamed for region errors in several cases. `best_blame_constraint` had a heuristic that tried to pinpoint the constraint causing an error by filtering out any constraints where the outliving region is unified with the ultimate target region being outlived. However, it used the SCCs of the region graph to do this, which is unreliable; in particular, if the target region is `'static`, or if there are cycles from the presence of invariant types, it was skipping over the constraints it should be blaming. As is the case in that issue, this could lead to confusing diagnostics. The simplest fix seems to work decently, judging by test stderr: this makes `best_blame_constraint` no longer filter constraints by their outliving region's SCC.
There are admittedly some quirks in the test output. In many cases, subdiagnostics that depend on the particular constraint being blamed have either started or stopped being emitted. After starting at this for quite a while, I think anything too fickle about whether it outputs based on the particular constraint being blamed should instead be looking at the constraint path as a whole, similar to what's done for [the placeholder-from-predicate note](https://github.com/rust-lang/rust/compare/master...dianne:rust:better-blame-constraints-for-static#diff-3c0de6462469af483c9ecdf2c4b00cb26192218ef2d5c62a0fde75107a74caaeR506).
Very many tests involving invariant types gained a note pointing out the types' invariance, but in a few cases it was lost. A particularly illustrative example is [tests/ui/lifetimes/copy_modulo_regions.stderr](https://github.com/rust-lang/rust/compare/master...dianne:rust:better-blame-constraints-for-static?expand=1#diff-96e1f8b29789b3c4ce2f77a5e0fba248829b97ef9d1ce39e7d2b4aa57b2cf4f0); I'd argue the new constraint is a better one to blame, but it lacks the variance diagnostic information that's elsewhere in the constraint path. If desired, I can try making that note check the whole path rather than just the blamed constraint.
The subdiagnostic [`BorrowExplanation::add_object_lifetime_default_note`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_borrowck/diagnostics/explain_borrow/enum.BorrowExplanation.html#method.add_object_lifetime_default_note) depends on a `Cast` being blamed, so [a special case](364ca7f99c) was necessary to keep it from disappearing from tests specifically testing for it. However, see the FIXME comment in that commit; I think the special case should be removed once that subdiagnostic works properly, but it's nontrivial enough to warrant a separate PR. Incidentally, this removes the note from a test where it was being added erroneously: in [tests/ui/borrowck/two-phase-surprise-no-conflict.stderr](https://github.com/rust-lang/rust/compare/master...dianne:rust:better-blame-constraints-for-static?expand=1#diff-8cf085af8203677de6575a45458c9e6b03412a927df879412adec7e4f7ff5e14), the object lifetime is explicitly provided and it's not `'static`.
This only includes previously existing tests (with a couple duplicates
removed). I plan on adding more comprarisons where the rules differ
once I've updated the pattern typing rules. I also haven't touched the
tests for new rules in old editions; I'll see how best to handle that
once those rules are updated as well.
This aims to reduce the complexity needed in the boolean logic for telling which
rules we're using to type patterns. If we still want the functionality this
removes, we can re-add it later, after some cleanup to pattern typing.
arm: add unstable soft-float target feature
This has an actual usecase as mentioned [here](https://github.com/rust-lang/rust/issues/116344#issuecomment-2575324988), and with my recent ARM float ABI changes there shouldn't be any soundness concerns any more. We will reject enabling this feature on `hf` targets, but disabling it on non-`hf` targets is entirely fine -- the target feature refers to whether softfloat emulation is used for float instructions, and is independent of the ABI which we set separately via `llvm_floatabi`.
Cc ``@workingjubilee``
rustdoc: use stable paths as preferred canonical paths
This accomplishes something like 16a4ad7d7b, but with the `rustc_allowed_through_unstable_modules` attribute instead of the path length.
Fixes#131676
Use a post-monomorphization typing env when mangling components that come from impls
When mangling associated methods of impls, we were previously using the wrong param-env. Instead of using a fully monomorphized param-env like we usually do in codegen, we were taking the post-analysis param-env, and treating it as an early binder to *re-substitute* the impl args. I've pointed out the problematic old code in an inline comment.
This would give us param-envs with possibly trivial predicates that would prevent normalization via param-env shadowing.
In the example test linked below, `tests/ui/symbol-names/normalize-in-param-env.rs`, this happens when we mangle the impl `impl<P: Point2> MyFrom<P::S> for P` with the substitution `P = Vec2`. Because the where clause of the impl is `P: Point2`, which elaborates to `[P: Point2, P: Point, <P as Point>::S projects-to <P as Point2>::S2]` and the fact that `impl Point2 for Vec2` normalizes `Vec2::S2` to `Vec2::S`, this causes a cycle.
The proper fix here is to use a fully monomorphized param-env for the case where the impl is properly substituted.
Fixes#135143
While #134081 uncovered this bug for legacy symbol mangling, it was preexisting for v0 symbol mangling. This PR fixes both. The test requires a "hack" because we strip the args of the instance we're printing for legacy symbol mangling except for drop glue, so we box a closure to ensure we generate drop glue.
r? oli-obk
Normalize each signature input/output in `typeck_with_fallback` with its own span
Applies the same hack as #106582 but to the args in typeck. Greatly improves normalization error spans from a signature.
[AIX] Port test case run-make/reproducible-build
The test case `run-make/reproducible-build` verifies that two identical invocations of the compiler produce the same output by comparing the linker arguments, resulting binaries, and other artifacts. However, the AIX linker command includes an argument that specifies the file containing exported symbols, with a file path that contains a randomly generated substring to prevent collisions between different linking processes. Additionally, the AIX XCOFF file header includes a 4-byte timestamp. This PR replaces the random substring with a placeholder and nullifies the timestamp field in the XCOFF files for the comparisons.
[generic_assert] Constify methods used by the formatting system
cc #44838
Starts the "constification" of all the elements required to allow the execution of the formatting system in constant environments.
```rust
const _: () = { panic!("{:?}", 1i32); };
```
Further stuff is blocked by #133999.
mark deprecated option as deprecated in rustc_session to remove copypasta and small refactor
This marks deprecated options as deprecated via flag in options table in rustc_session, which removes copypasted deprecation text from rustc_driver_impl.
This also adds warning for deprecated `-C ar` option, which didn't emitted any warnings before.
Makes `inline_threshold` `[UNTRACKED]`, as it do nothing.
Adds few tests.
See individual commits.
rustdoc: Fix mismatched capitalization in sidebar
Previously, the main content used "Aliased Type", while the sidebar said "Aliased type". Now, they both say "Aliased Type", which is the more common capitalization in Rustdoc.
See the following link for an example.
https://doc.rust-lang.org/1.83.0/std/io/type.Result.html
Suggest to replace tuple constructor through projection
See the code example. when `Self::Assoc` normalizes to a struct that has a tuple constructor, you cannot construct the type via `Self::Assoc(field, field)`. Instead, suggest to replace it with the correct named struct.
Fixes#120871
Don't ice on bad transmute in typeck in new solver
Old trait solver ends up getting its infcx tainted because we try to normalize the type, but the new trait solver doesn't. This means we try to compute the stalled transmute obligations, which tries to normalize a type an ICEs. Let's make this a delayed bug.
r? lcnr
Improve diagnostics for `HostEffectPredicate` in the new solver
Adds derived cause for host effect predicates. Some diagnostics regress, but that's connected to the fact that our predicate visitor doesn't play well with aliases just yet.
Add support for wasm exception handling to Emscripten target
This is a draft because we need some additional setting for the Emscripten target to select between the old exception handling and the new exception handling. I don't know how to add a setting like that, would appreciate advice from Rust folks. We could maybe choose to use the new exception handling if `Ctarget-feature=+exception-handling` is passed? I tried this but I get errors from llvm so I'm not doing it right.
The SCCs of the region graph are not a reliable heuristic to use for blaming an interesting
constraint for diagnostics. For region errors, if the outlived region is `'static`, or the involved
types are invariant in their lifetiems, there will be cycles in the constraint graph containing both
the target region and the most interesting constraints to blame. To get better diagnostics in these
cases, this commit removes that heuristic.
Previously, the main content used "Aliased Type", while the sidebar said
"Aliased type". Now, they both say "Aliased Type", which is the more common
capitalization in Rustdoc.
See the following link for an example.
https://doc.rust-lang.org/1.83.0/std/io/type.Result.html
