Remove `Option<!>` return types.
Several compiler functions have `Option<!>` for their return type. That's odd. The only valid return value is `None`, so why is this type used?
Because it lets you write certain patterns slightly more concisely. E.g. if you have these common patterns:
```
let Some(a) = f() else { return };
let Ok(b) = g() else { return };
```
you can shorten them to these:
```
let a = f()?;
let b = g().ok()?;
```
Huh.
An `Option` return type typically designates success/failure. How should I interpret the type signature of a function that always returns (i.e. doesn't panic), does useful work (modifying `&mut` arguments), and yet only ever fails? This idiom subverts the type system for a cute syntactic trick.
Furthermore, returning `Option<!>` from a function F makes things syntactically more convenient within F, but makes things worse at F's callsites. The callsites can themselves use `?` with F but should not, because they will get an unconditional early return, which is almost certainly not desirable. Instead the return value should be ignored. (Note that some of callsites of `process_operand`, `process_immedate`, `process_assign` actually do use `?`, though the early return doesn't matter in these cases because nothing of significance comes after those calls. Ugh.)
When I first saw this pattern I had no idea how to interpret it, and it took me several minutes of close reading to understand everything I've written above. I even started a Zulip thread about it to make sure I understood it properly. "Save a few characters by introducing types so weird that compiler devs have to discuss it on Zulip" feels like a bad trade-off to me. This commit replaces all the `Option<!>` return values and uses `else`/`return` (or something similar) to replace the relevant `?` uses. The result is slightly more verbose but much easier to understand.
r? ``````@cjgillot``````
Simplify some extern providers
Simplifies some extern crate providers:
1. Generalize the `ProcessQueryValue` identity impl to work on non-`Option` types.
2. Allow `ProcessQueryValue` to wrap its output in an `EarlyBinder`, to simplify `explicit_item_bounds`/`explicit_item_super_predicates`.
3. Use `{ table }` and friends more when possible.
Bump backtrace to 0.3.74~ish
Commit: https://github.com/rust-lang/backtrace-rs/commit/230570f
This should help with backtraces on Android, QNX NTO 7.0, and Windows.
It addresses a case of backtrace incurring undefined behavior on Android.
Re-enable android tests/benches in alloc/core
This is basically a revert of https://github.com/rust-lang/rust/pull/73729. These tests better work on android now; it's been 4 years and we don't use dlmalloc on that target anymore.
And I've validated that they should pass now with a try-build :)
Deny `wasm_c_abi` lint to nudge the last 25%
This shouldn't affect projects indirectly depending on wasm-bindgen because cargo passes `--cap-lints=allow` when building dependencies.
The motivation is that the ecosystem has mostly taken up the versions of wasm-bindgen that are compatible in general, but ~25% or so of recent downloads remain on lower versions. However, this change might still be unnecessarily disruptive. I mostly propose it as a discussion point.
linker: Synchronize native library search in rustc and linker
Also search for static libraries with alternative naming (`libname.a`) on MSVC when producing executables or dynamic libraries, and not just rlibs.
This unblocks https://github.com/rust-lang/rust/pull/123436.
try-job: x86_64-msvc
rustdoc-json: Add test for `Self` type
Inspired by #128471, the rustdoc-json suite had no tests in place for the `Self` type. This PR adds one.
I've also manually checked locally that this test passes on 29e924841f, confirming that adding `clean::Type::SelfTy` didn't change the JSON output. (potentially adding a self type to json (insead of (ab)using generic) is tracked in #128522)
Updates #81359
r? ````````@fmease````````
Separate core search logic with search ui
Currenty, the `search.js` mixed with UI/DOM manipulation codes and search logic codes, I propose to extract the search logic to a class for following benefits:
- Clean code. Separation of DOM manipulation and search logic can lead better code maintainability and easy code testings.
- Easy share the search logic for third party to utilize the search function, such as [Rust Search Extension](https://rust.extension.sh), https://query.rs.
This PR added a new class called `DocSearch`, which mainly expose following methods:
```js
class DocSearch {
// Dependency inject searchIndex, rootPath and searchState
constructor(rawSearchIndex, rootPath, searchState) {
// build search index...
}
static parseQuery(userQuery) {
}
async execQuery(parsedQuery, filterCrates, currentCrate) {
}
}
```
Don't make statement nonterminals match pattern nonterminals
Right now, the heuristic we use to check if a token may begin a pattern nonterminal falls back to `may_be_ident`:
ef71f1047e/compiler/rustc_parse/src/parser/nonterminal.rs (L21-L37)
This has the unfortunate side effect that a `stmt` nonterminal eagerly matches against a `pat` nonterminal, leading to a parse error:
```rust
macro_rules! m {
($pat:pat) => {};
($stmt:stmt) => {};
}
macro_rules! m2 {
($stmt:stmt) => {
m! { $stmt }
};
}
m2! { let x = 1 }
```
This PR fixes it by more accurately reflecting the set of nonterminals that may begin a pattern nonterminal.
As a side-effect, I modified `Token::can_begin_pattern` to work correctly and used that in `Parser::nonterminal_may_begin_with`.
Try to reduce space usage in dist CI
We have had recurrent CI problems as a result of GitHub adding a new version of Xcode to its runners[^0], which has consumed ~40GB of space which served as padding. Try to reduce the number of Xcodes on our systems, because we only use Xcode 14 in actual practice. Also, try to move files instead of pointlessly copy them when we're at the end of the job.
I could not resist addressing a few shellcheck lints while I was at it.
[^0]: https://github.com/actions/runner-images/issues/10511
We want to allow setting this on the CLI, override it only in MIR
passes, and disable it altogether in mir-opt tests.
The default value is "only for NLL MIR dumps", which is considered off
for all intents and purposes, except for `rustc_borrowck` when an NLL
MIR dump is requested.
Several compiler functions have `Option<!>` for their return type.
That's odd. The only valid return value is `None`, so why is this type
used?
Because it lets you write certain patterns slightly more concisely. E.g.
if you have these common patterns:
```
let Some(a) = f() else { return };
let Ok(b) = g() else { return };
```
you can shorten them to these:
```
let a = f()?;
let b = g().ok()?;
```
Huh.
An `Option` return type typically designates success/failure. How should
I interpret the type signature of a function that always returns (i.e.
doesn't panic), does useful work (modifying `&mut` arguments), and yet
only ever fails? This idiom subverts the type system for a cute
syntactic trick.
Furthermore, returning `Option<!>` from a function F makes things
syntactically more convenient within F, but makes things worse at F's
callsites. The callsites can themselves use `?` with F but should not,
because they will get an unconditional early return, which is almost
certainly not desirable. Instead the return value should be ignored.
(Note that some of callsites of `process_operand`, `process_immedate`,
`process_assign` actually do use `?`, though the early return doesn't
matter in these cases because nothing of significance comes after those
calls. Ugh.)
When I first saw this pattern I had no idea how to interpret it, and it
took me several minutes of close reading to understand everything I've
written above. I even started a Zulip thread about it to make sure I
understood it properly. "Save a few characters by introducing types so
weird that compiler devs have to discuss it on Zulip" feels like a bad
trade-off to me. This commit replaces all the `Option<!>` return values
and uses `else`/`return` (or something similar) to replace the relevant
`?` uses. The result is slightly more verbose but much easier to
understand.
This keeps it up-to-date by moving from 0.5.6 to 0.5.7. While here I've
additionally updated some other wasm-related dependencies in the
workspace to keep them up-to-date and try to avoid duplicate versions as
well.
The test code did have an inference failure, but that would have failed
on Rust 1.79 and earlier too. Now it is rewritten to be specifically
affected by 1.80's `impl FromIterator<_> for Box<str>`.
This commit fixes an assert in the WASI-specific implementation of
thread sleep to ensure that sleeping for a very large period of time
blocks instead of panicking. This can come up when testing programs that
sleep "forever", for example.
