refactor match guard
This is the first step to implement RFC 2294: if-let-guard. Tracking issue: https://github.com/rust-lang/rust/issues/51114
The second step should be introducing another variant `IfLet` in the Guard enum. I separated them into 2 PRs for the convenience of reviewers.
r? @petrochenkov
Add Error::source method per RFC 2504.
This implements part of RFC 2504.
* Adds `Error::source`, a replacement for `Error::cause` with the "right" signature, which will be instantly stable.
* Deprecates `Error::cause` in 1.33 (this choice was based on the precedent in #52994, which we haven't finalized).
* Redefines `Error::cause` to delegate to `Error::source` (the delegation can only go in this direction, not the other).
@rfcbot fcp merge
set cfg(rustdoc) when rustdoc is running on a crate
When using `#[doc(cfg)]` to document platform-specific items, it's a little cumbersome to get all the platforms' items to appear all at once. For example, the standard library adds `--cfg dox` to rustdoc's command line whenever it builds docs, and the documentation for `#![feature(doc_cfg)]` suggests using a Cargo feature to approximate the same thing. This is a little awkward, because you always need to remember to set `--features dox` whenever you build documentation.
This PR proposes making rustdoc set `#[cfg(rustdoc)]` whenever it runs on a crate, to provide an officially-sanctioned version of this that is set automatically. This way, there's a standardized way to declare that a certain version of an item is specifically when building docs.
To try to prevent the spread of this feature from happening too quickly, this PR also restricts the use of this flag to whenever `#![feature(doc_cfg)]` is active. I'm sure there are other uses for this, but right now i'm tying it to this feature. (If it makes more sense to give this its own feature, i can easily do that.)
Make Arc cloning mechanics clearer in module docs
Add some more wording to module documentation regarding how
`Arc::clone()` works, as some users have assumed cloning Arc's
to work via dereferencing to inner value as follows:
use std::sync::Arc;
let myarc = Arc::new(1);
let myarcref = myarc.clone();
assert!(1 == myarcref);
Instead of the actual mechanic of referencing the existing
Arc value:
use std::sync::Arg;
let myarc = Arc::new(1);
let myarcref = myarc.clone();
assert!(myarcref == &myarc); // not sure if assert could assert this in the real world
bench: libcore: fix build failure of any.rs benchmark (use "dyn Any")
fixes
````
error: trait objects without an explicit `dyn` are deprecated
--> libcore/../libcore/benches/any.rs:18:36
|
18 | let mut y = &mut x as &mut Any;
| ^^^ help: use `dyn`: `dyn Any`
|
= note: requested on the command line with `-D bare-trait-objects`
````
Add rust-gdbgui script.
This script invokes the [gdbgui](https://gdbgui.com/) graphical GDB front-end with the Rust pretty printers loaded. The script does not install gdbgui, that must be done manually.
As an escapee from Visual Studio it is nice to have a point-and-click debugger. This script invokes `gdbgui` similarly to the way that `rust-gdb` invokes `gdb` - I copied that script as a starting point.
Because it is a wrapper around a wrapper you don't have as much flexibility in passing arguments to GDB and I could not find a way to eliminate the single quotes you have to use when you want to pass arguments to your program (`gdbgui` supposedly supports an `--args` option which I think should allow this, but I couldn't get it to work, my shell-fu is weak). Still, I find this very usable for debugging programs, and it is a lot more approachable than gdb in the terminal.
Implement the `min_const_fn` feature gate
cc @RalfJung @eddyb
r? @Centril
implements the feature gate for #53555
I added a hack so the `const_fn` feature gate also enables the `min_const_fn` feature gate. This ensures that nightly users of `const_fn` don't have to touch their code at all.
The `min_const_fn` checks are run first, and if they succeeded, the `const_fn` checks are run additionally to ensure we didn't miss anything.
This commit adds a few changes for atomic instructions on the
`wasm32-unknown-unknown` target. Atomic instructions are not yet stable in
WebAssembly itself but there are multiple implementations and LLVM has support
for the proposed instruction set, so let's work on exposing it!
Here there are a few inclusions:
* The `atomics` feature was whitelisted for LLVM, allowing code in Rust to
enable/disable/gate on this.
* The `singlethread` option is turned off for wasm when the `atomics` feature is
enabled. This means that by default wasm won't be lowering with atomics, but
when atomics are enabled globally we'll turn off single-threaded mode to
actually codegen atomics. This probably isn't what we'll want in the long term
but for now it should work.
* Finally the maximum atomic width is increased to 64 to reflect the current
wasm spec.
Backwards compatibility for tool/clippy lints
cc #44690
cc https://github.com/rust-lang-nursery/rust-clippy/pull/2977#issuecomment-409706557
This is the next step towards `tool_lints`.
This makes Clippy lints still work without scoping, but will warn and suggest the new scoped name. This warning will only appear if the code is checked with Clippy itself.
There is still an issue with using the old lint name in inner attributes. For inner attributes the warning gets emitted twice. I'm currently not really sure why this happens, but will try to fix this ASAP.
r? @Manishearth
Update LLVM submodule
This commit updates the LLVM submodule to the current trunk of LLVM itself. This
brings a few notable improvements for the wasm target:
* Support for wasm atomic instructions is greatly improved
* Renamed memory wasm intrinsics are fully supported
* LLD has fixed a quadratic execution bug with large numbers of relocations in
wasm files.
The compiler-rt submodule has been updated in tandem as well.
This commit updates the LLVM submodule to the current trunk of LLVM itself. This
brings a few notable improvements for the wasm target:
* Support for wasm atomic instructions is greatly improved
* Renamed memory wasm intrinsics are fully supported
* LLD has fixed a quadratic execution bug with large numbers of relocations in
wasm files.
The compiler-rt submodule has been updated in tandem as well.
rustdoc: add flag to control the html_root_url of dependencies
The `--extern-html-root-url` flag in this PR allows one to override links to crates whose docs are not already available locally in the doc bundle. Docs.rs currently uses a version of this to make sure links to other crates go into that crate's docs.rs page. See the included test for intended use, but the idea is as follows:
Calling rustdoc with `--extern-html-root-url crate=https://some-url.com` will cause rustdoc to override links that point to that crate to instead be replaced with a link rooted at `https://some-url.com/`. (e.g. for docs.rs this would be `https://docs.rs/crate/0.1.0` or the like.) Cheekily, rustup could use these options to redirect links to std/core/etc to instead point to locally-downloaded docs, if it so desired.
Fixes https://github.com/rust-lang/rust/issues/19603
Fix promotion stability hole in old borrowck
r? @nikomatsakis
I screwed up the promotion stability checks. Big time. They were basically nonexistant. We had tests for it. I also screwed up said tests. This is in stable already :(
Basically stability checks of promotion only worked if you tried to use a const fn defined in the same crate.
cc @eddyb
