- cast `&[Arm]` to `&[Arm; 2]` early on to hopefully avoid bounds checks
- use `if let [pattern] = X { .. }` instead of
`if let patterns = X { let pattern = patterns[0]; .. }`
- use `Symbol`s instead of `&str`s
- reduce indentation
Don't condition RUSTDOC_LIBDIR on `--no-doc`
In d94e7ff065, `rustdoc_path` was changed to ignore `want_rustdoc` (which is just whether `--no-doc` was passed). But RUSTDOC_LIBDIR wasn't kept in sync. Rather than trying to keep `rustdoc_path` in sync with `RUSTDOC_LIBDIR`, just pass LIBDIR to the rustc shim unconditionally.
This fix allows calling `ensure(doc::Step)` from a non-doc top-level Step, even if `--no-doc` was present in the command line.
Rename various "concrete opaque type" things to say "hidden type"
r? lcnr
I've found "concrete opaque type" terminology to be somewhat confusing as in conversation and when explaining opaque type stuff to people I always just talk about things in terms of hidden types. Also the hidden types of opaques are very much not *concrete* in the same sense that a type without any generic parameters is concrete which is an unfortunate overlap in terminology.
I've tried to update comments to also stop referring to things as concrete opaque types but this is mostly best effort as it difficult to find all such cases amongst the massive amounts of uses of "concrete" or "hidden" across the whole compiler.
cmse: fix 'region variables should not be hashed'
tracking issue: https://github.com/rust-lang/rust/issues/81391
fixes https://github.com/rust-lang/rust/issues/131639
Some background: the `cmse-nonsecure-call` calling convention is used for a call from "secure" to "non-secure" code. To make sure that "non-secure" cannot read any secrets, restrictions are put on the signatures of functions with this calling convention: they can only use 4 arguments for passing arguments, and one register for passing a result. No arguments are passed via the stack, and all other registers are cleared before the call.
We check during `hir_ty_lowering` that the signature follows these rules. We do that by determining and then inspecting the layout of the type. That works well overall, but can run into asserts when the type itself is ill-formed. This PR fixes one such case.
I believe that the fix here, just erasing the regions, is the right shape, but there may be some nuance that I'm missing.
r? types
Point at fn bound that introduced lifetime obligation
The last note is new
```
error[E0597]: `c` does not live long enough
--> $DIR/without-precise-captures-we-are-powerless.rs:19:20
|
LL | fn simple<'a>(x: &'a i32) {
| -- lifetime `'a` defined here
...
LL | let c = async move || { println!("{}", *x); };
| - binding `c` declared here
LL | outlives::<'a>(c());
| ---------------^---
| | |
| | borrowed value does not live long enough
| argument requires that `c` is borrowed for `'a`
LL | outlives::<'a>(call_once(c));
LL | }
| - `c` dropped here while still borrowed
|
note: requirement that `c` is borrowed for `'a` introduced here
--> $DIR/without-precise-captures-we-are-powerless.rs:7:33
|
LL | fn outlives<'a>(_: impl Sized + 'a) {}
| ^^
```
When encountering a `ConstraintCategory::Predicate` in a funtion call, point at the `Span` for that `Predicate` to explain where the lifetime obligation originates from.
CC rust-lang/rust#55307.
Make replacement suggestion `_` in type verbose
```
error[E0121]: the placeholder `_` is not allowed within types on item signatures for return types
--> $DIR/in-signature.rs:6:21
|
LL | fn arr_fn() -> [u8; _] {
| ^ not allowed in type signatures
|
help: replace with the correct return type
|
LL - fn arr_fn() -> [u8; _] {
LL + fn arr_fn() -> [u8; 3] {
|
```
Skip cleanups on unsupported targets
This commit is an update to the `AbortUnwindingCalls` MIR pass in the compiler. Specifically a new boolean is added for "can this target possibly unwind" and if that's `false` then terminators are all adjusted to be unreachable/not present. The end result is that this fixesrust-lang/rust#140293 for wasm targets.
The motivation for this PR is that currently on WebAssembly targets the usage of the `C-unwind` ABI can lead LLVM to either (a) emit exception-handling instructions or (b) hit a LLVM-ICE-style codegen error. WebAssembly as a base instruction set does not support unwinding at all, and a later proposal to WebAssembly, the exception-handling proposal, was what enabled this. This means that the current intent of WebAssembly targets is that they maintain the baseline of "don't emit exception-handling instructions unless enabled". The commit here is intended to restore this behavior by skipping these instructions even when `C-unwind` is present.
Exception-handling is a relatively tricky and also murky topic in WebAssembly, however. There are two sets of instructions LLVM can emit for WebAssembly exceptions, Rust's Emscripten target supports exceptions, WASI targets do not, the LLVM flags to enable this are not always obvious, and additionally this all touches on "changing exception-handling behavior should be a target-level concern, not a feature". Effectively WebAssembly's exception-handling integration into Rust is not finalized at this time. The best idea at this time is that a parallel set of targets will eventually be added which support exceptions, but it's not clear if/when to do this. In the meantime the goal is to keep existing targets working while still enabling experimentation with exception-handling with `-Zbuild-std` and various permutations of LLVM flags.
To that extent this commit does not blanket disable these landing pads and cleanup routines for WebAssembly but instead checks to see if panic=unwind is enabled or if `+exception-handling` is enabled. Tests are updated here as well to account for this where, by default, using a `C-unwind` ABI won't affect Rust codegen at all. If `+exception-handling` is enabled, however, then Rust codegen will look like native platforms where exceptions are caught and the program aborts. More-or-less I've done my best to keep exceptions working on wasm where it's possible to have them work, but turned them off where they're not supposed to be emitted.
Closesrust-lang/rust#140293
The issue that I saw made me rethink the lint design by quite a lot, so
I decided to include that change in this PR
fixesrust-lang/rust-clippy#9000
changelog: [`double_parens`]: add structured suggestions
changelog: [`double_parens`]: fix FP when macros are involved
In d94e7ff065, `rustdoc_path` was changed
to ignore `want_rustdoc` (which is just whether `--no-doc` was passed).
But RUSTDOC_LIBDIR wasn't kept in sync. Rather than trying to keep
`rustdoc_path` in sync with `RUSTDOC_LIBDIR`, just pass LIBDIR to the
rustc shim unconditionally.
This fix allows calling `ensure(doc::Step)` from a non-doc top-level
Step, even if `--no-doc` was present in the command line.