Ensure required submodules at the same time as updating existing submodules
In practice, this would always happen at the same time, but putting them next to each other makes that more obvious and ensures it doesn't change in the future. It also avoids the difference affecting `cargo metadata` somehow.
This is based on https://github.com/rust-lang/rust/pull/104952 for convenience to avoid merge conflicts, but doesn't depend on that PR.
Streamline the user experience for `x.py setup`
## Don't update submodules for x setup
Before, the submodule handling was very jank and would update *between two interactive prompts*:
```
; x setup
Building rustbuild
Finished dev [unoptimized] target(s) in 0.05s
Welcome to the Rust project! What do you want to do with x.py?
a) library: Contribute to the standard library
Please choose one (a/b/c/d/e): a
Updating submodule library/backtrace
Submodule 'library/backtrace' (https://github.com/rust-lang/backtrace-rs.git) registered for path 'library/backtrace'
error: you asked `x.py` to setup a new config file, but one already exists at `config.toml`
Build completed unsuccessfully in 0:00:02
```
That's not a great user experience because you need to wait a long time between prompts.
It would be possible to move the submodule handling either before or after the prompt, but it seems
better to just not require submodules to be checked out at all, to minimize the time spend waiting
just to create a new configuration.
## Revamp the order setup executes
- Create `config.toml` last. It's the most likely to error, and used to stop later steps from executing
- Don't print an error message + exit if the git hook already exists; that's expected
PartialEq: PERs are homogeneous
PartialEq claims that it corresponds to a PER, but that is only a well-defined statement when `Rhs == Self`. There is no standard notion of PER on a relation between two different sets/types. So move this out of the first paragraph and clarify this.
CI: reduce docker image sizes
Reduces docker image sizes by using simple tips like: cleaning packet managers cache, squashing sequential installation steps into one.
For some images this gives ~40mb for apt-based images (not so much), but ~200mb(!) for centos one.
Send `VecDeque::from_iter` via `Vec::from_iter`
Since it's O(1) to convert between them now, might as well reuse the logic.
Mostly for the various specializations it does, but might also save some monomorphization work if, say, people collect slice iterators into both `Vec`s and `VecDeque`s.
Avoid some `InferCtxt::build` calls
Either because we're inside of an `InferCtxt` already, or because we're not in a place where we'd ever see inference vars.
r? types
Make sure async constructs do not `impl Generator`
Async lowering turns async functions and blocks into generators internally.
Though these special kinds of generators should not `impl Generator` themselves.
The other way around, normal generators should not `impl Future`.
This was discovered in https://github.com/rust-lang/rust/pull/105082#issuecomment-1332210907 and is a regression from https://github.com/rust-lang/rust/pull/104321.
r? `@compiler-errors`
rustc_codegen_ssa: Fix for codegen_get_discr
When doing the optimized implementation of getting the discriminant, the arithmetic needs to be done in the tag type so wrapping behavior works correctly.
Fixes#104519
Rollup of 6 pull requests
Successful merges:
- #101975 (Suggest to use . instead of :: when accessing a method of an object)
- #105141 (Fix ICE on invalid variable declarations in macro calls)
- #105224 (Properly substitute inherent associated types.)
- #105236 (Add regression test for #47814)
- #105247 (Use parent function WfCheckingContext to check RPITIT.)
- #105253 (Update a couple of rustbuild deps)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Update a couple of rustbuild deps
These mostly remove some dependency edges potentially making compilation of rustbuild itself a tiny bit faster. I hoped to be able to completely remove some dependencies, but other than replacing ansi_term with yansi all dependencies are still used.
Fix ICE on invalid variable declarations in macro calls
This fixes ICE that happens with invalid variable declarations in macro calls like:
```rust
macro_rules! m { ($s:stmt) => {} }
m! { var x }
m! { auto x }
m! { mut x }
```
Found this is because of not collecting tokens on recovery, so I changed to force collect them.
Fixes https://github.com/rust-lang/rust/issues/103529.
Remove drop order twist of && and || and make them associative
Previously a short circuiting binop chain (chain of && or ||s) would drop the temporaries created by the first element after all the other elements, and otherwise follow evaluation order. So `f(1).g() && f(2).g() && f(3).g() && f(4).g()` would drop the temporaries in the order `2,3,4,1`. This made `&&` and `||` non-associative regarding drop order. In other words, adding ()'s to the expression would change drop order: `f(1).g() && (f(2).g() && f(3).g()) && f(4).g()` for example would drop in the order `3,2,4,1`.
As, except for the bool result, there is no data returned by the sub-expressions of the short circuiting binops, we can safely discard of any temporaries created by the sub-expr. Previously, code was already putting the rhs's into terminating scopes, but missed it for the lhs's.
This commit addresses this "twist". We now also put the lhs into a terminating scope. The drop order of the above expressions becomes `1,2,3,4`.
There might be code relying on the current order, and therefore I'd recommend doing a crater run to gauge the impact. I'd argue that such code is already quite wonky as it is one `foo() &&` addition away from breaking. ~~For the impact, I don't expect any *build* failures, as the compiler gets strictly more tolerant: shortening the lifetime of temporaries only expands the list of programs the compiler accepts as valid. There might be *runtime* failures caused by this change however.~~ Edit: both build and runtime failures are possible, e.g. see the example provided by dtolnay [below](https://github.com/rust-lang/rust/pull/103293#issuecomment-1285341113). Edit2: the crater run has finished and [results](https://github.com/rust-lang/rust/pull/103293#issuecomment-1292275203) are that there is only one build failure which is easy to fix with a +/- 1 line diff.
I've included a testcase that now compiles thanks to this patch.
The breakage is also limited to drop order relative to conditionals in the && chain: that is, in code like this:
```Rust
let hello = foo().hi() && bar().world();
println!("hi");
```
we already drop the temporaries of `foo().hi()` before we reach "hi".
I'd ideally have this PR merged before let chains are stabilized. If this PR is taking too long, I'd love to have a more restricted version of this change limited to `&&`'s in let chains: the `&&`'s of such chains are quite special anyways as they accept `let` bindings, in there the `&&` is therefore more a part of the "if let chain" construct than a construct of its own.
Fixes#103107
Status: waiting on [this accepted FCP](https://github.com/rust-lang/rust/pull/103293#issuecomment-1293411354) finishing.