interpret: do not force_allocate all return places
A while ago I cleaned up our `PlaceTy` a little, but as a side-effect of that, return places had to always be force-allocated. That turns out to cause quite a few extra allocations, and for a project we are doing where we marry Miri with a model checker, that means a lot of extra work -- local variables are just so much easier to reason about than allocations.
So, this PR brings back the ability to have the return place be just a local of the caller. To make this work cleanly I had to rework stack pop handling a bit, which also changes the output of Miri in some cases as the span for errors occurring during a particular phase of stack pop changed.
With these changes, a no-std binary with a function of functions that just take and return scalar types and that uses no pointers now does not move *any* local variables into memory. :)
r? `@oli-obk`
One downside to this is that, since the patterns matched against (on the
left) are quite long, it's a bit difficult to see what's even getting
matched. Using `matches!()` could help with that
changelog: none
Intrinsics are not real functions and as such don't have any calling
convention. Trying to compute a calling convention for an intrinsic
anyway is a nonsensical operation.
It never fails, so it doesn't need to return `Result`. And the
`ItemType` in the result is just a copy of the one passed in via the
`shortty` arg, so it can also be removed.
Rollup of 8 pull requests
Successful merges:
- rust-lang/rust#134696 (Implement `normalize_lexically`)
- rust-lang/rust#140539 (Simplify `attribute_groups`)
- rust-lang/rust#140863 ([rustdoc] Unify type aliases rendering with other ADT)
- rust-lang/rust#140936 (Clarify WTF-8 safety docs)
- rust-lang/rust#140952 (Specify that split_ascii_whitespace uses the same definition as is_ascii_whitespace)
- rust-lang/rust#141472 (Attempt to improve the `std::fs::create_dir_all` docs related to atomicity)
- rust-lang/rust#141502 (ci: move PR job x86_64-gnu-tools to codebuild)
- rust-lang/rust#141559 (const-check: stop recommending the use of rustc_allow_const_fn_unstable)
r? `@ghost`
`@rustbot` modify labels: rollup
const-check: stop recommending the use of rustc_allow_const_fn_unstable
I have seen way too many people see the compiler suggest this attribute and then just apply it without a second thought. This is bad. So let's just stop recommending it; for the rare case where someone needs it, they'll eventually ask us and that way we can be sure that it is truly needed. The dev-guide still also explains `rustc_allow_const_fn_unstable`.
Cc ``@rust-lang/wg-const-eval``
Attempt to improve the `std::fs::create_dir_all` docs related to atomicity
The original paragraph was added in rust-lang/rust#124520. It doesn't match the actual code logic. It says "function returns an error" if "the parent components" _(which also implies directories)_ "have been created already". The code is as follows:
e88e854634/library/std/src/fs.rs (L3146)e88e854634/library/std/src/fs.rs (L3160)
These lines suppress all errors if any path component is a directory. I've updated the paragraph to mirror this.
Clarify WTF-8 safety docs
This PR is a follow-up to PR #140159, which clarifies ~~two things~~:
- the WTF-8 safety comment [was confusing](https://github.com/rust-lang/rust/pull/140159#discussion_r2082766965), either surrogate condition is actually sufficient for safety, both are not required
- ~~the private `os_str::Slice` type name is easily confused with `std::slice`~~
~~Happy to bikeshed the `OsSlice` name, other alternatives are `OsStrSlice` and `StrSlice`. Now it's got a distinct name from `std::slice`, it's easy to search and replace.~~
cc ``@thaliaarchi`` ``@workingjubilee``
[rustdoc] Unify type aliases rendering with other ADT
Fixes#140739.
Better reviewed one commit at a time.
Just one thing I'm wondering: should we also render non-`repr` attributes? If so, I wonder if we shouldn't simply change `clean::TypeAlias` to contain the other ADT directly (`Struct`, `Enum` and `Union`) and remove the `TypeAlias::generics` field.
Can be done in a follow-up too.
cc ``@camelid``
r? ``@notriddle``
