interpret: clobber return place when calling function
Makes sure the callee cannot observe the previous contents of the return place, and the caller cannot read any of the old return place contents even if the function unwinds.
I don't think we can test for this though, that would require some strange hand-written MIR.
r? `````@oli-obk`````
Fix UI issues with Rustdoc scrape-examples feature.
A few regressions have been introduced into scrape-examples in the last few months. This commit fixes those regressions:
* Help file was being loaded from the wrong place (introduced in f9e1f6ffdf).
* CSS selector in JS has a typo (introduced in 14897180ae).
* Line numbers in scraped example code snippets are overflowing (not sure if this was ever fixed). Changing from flexbox to grid display fixed this issue.
feed resolver_for_lowering instead of storing it in a field
r? `@cjgillot`
opening this as
* a discussion for `no_hash` + `feedable` queries. I think we'll want those, but I don't quite understand why they are rejected beyond a double check of the stable hashes for situations where the query is fed but also read from incremental caches.
* and a discussion on removing all untracked fields from TyCtxt and setting it up so that they are fed queries instead
Given that attributes is stored in a separate BTreeMap, it's not necessary
to pass it in when constructing `hir::Expr`. We can just construct
`hir::Expr` and then call `self.lower_attrs` later if it needs attributes.
As most desugaring code don't use attributes, this allows some code cleanup.
Disable top down MIR inlining
The current MIR inliner has exponential behavior in some cases: <https://godbolt.org/z/7jnWah4fE>. The cause of this is top-down inlining, where we repeatedly do inlining like `call_a() => { call_b(); call_b(); }`. Each decision on its own seems to make sense, but the result is exponential.
Disabling top-down inlining fundamentally prevents this. Each call site in the original, unoptimized source code is now considered for inlining exactly one time, which means that the total growth in MIR size is limited to number of call sites * inlining threshold.
Top down inlining may be worth re-introducing at some point, but it needs to be accompanied with a principled way to prevent this kind of behavior.
This ensures that the error is printed even for unused variables,
as well as unifying the handling between the LLVM and GCC backends.
This also fixes unusual behavior around exported Rust-defined variables
with linkage attributes. With the previous behavior, it appears to be
impossible to define such a variable such that it can actually be imported
and used by another crate. This is because on the importing side, the
variable is required to be a pointer, but on the exporting side, the
type checker rejects static variables of pointer type because they do
not implement `Sync`. Even if it were possible to import such a type, it
appears that code generation on the importing side would add an unexpected
additional level of pointer indirection, which would break type safety.
This highlighted that the semantics of linkage on Rust-defined variables
is different to linkage on foreign items. As such, we now model the
difference with two different codegen attributes: linkage for Rust-defined
variables, and import_linkage for foreign items.
This change gives semantics to the test
src/test/ui/linkage-attr/auxiliary/def_illtyped_external.rs which was
previously expected to fail to compile. Therefore, convert it into a
test that is expected to successfully compile.
The update to the GCC backend is speculative and untested.
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.
`EarlyContextAndPass` wraps a single early lint pass. We aggregate
multiple passes into that single pass by using `EarlyLintPassObjects`.
This commit removes `EarlyLintPassObjects` by changing
`EarlyContextAndPass` into `EarlyContextAndPasses`. I.e. it just removes
a level of indirection. This makes the code simpler and slightly faster.
The commit does likewise for late lints.
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`
