Sync LLVM submodule if it has been initialized
Since having enabled the download-ci-llvm option,
and having rebased on top of #76864,
I've noticed that I had to update the llvm-project
submodule manually if it was checked out.
Orignally, the submodule update logic was
introduced to reduce the friction for contributors
to manage the submodules, or in other words, to prevent
getting PRs that have unwanted submodule rollbacks
because the contributors didn't run git submodule update.
This commit adds logic to ensure there is no inadvertent
LLVM submodule rollback in a PR if download-ci-llvm
(or llvm-config) is enabled. It will detect whether the
llvm-project submodule is initialized, and if so, update
it in any case. If it is not initialized, behaviour is
kept to not do any update/initialization.
An alternative to the chosen implementation would
be to not pass the --init command line arg to
`git submodule update` for the src/llvm-project
submodule. This would show a confusing error message
however on all builds with an uninitialized repo.
We could pass the --silent param, but we still want
it to print something if it is initialized and has
to update something.
So we just do a manual check for whether the
submodule is initialized.
Clean up and improve some docs
* compiler docs
* Don't format list as part of a code block
* Clean up some other formatting
* rustdoc book
* Update CommonMark spec version to latest (0.28 -> 0.29)
* Clean up some various wording and formatting
Doc formating consistency between slice sort and sort_unstable, and big O notation consistency
Updated documentation for slice sorting methods to be consistent between stable and unstable versions, which just ended up being minor formatting differences.
I also went through and updated any doc comments with big O notation to be consistent with #74010 by italicizing them rather than having them in a code block.
Avoid extraneous space between visibility kw and ident for statics
Today, given a static like `static mut FOO: usize = 1`, rustdoc would
emit `static mut FOO: usize = 1`, as it emits both the mutability kw
with a space and reserves a space after the mutability kw. This patch
fixes that misformatting.
This patch also adds some tests for emit of other statics, as I could
not find an existing test devoted to statics.
Fixing escaping to ensure generation of welformed json.
doc tests' json name have a filename in them. When json test output is asked for on windows currently produces invalid json.
Tracking issue for json test output: #49359
Implement TryFrom between NonZero types.
This will instantly be stable, as trait implementations for stable types and traits can not be `#[unstable]`.
Closes#77258.
@rustbot modify labels: +T-libs
Link to "Contributing to Rust" rather than "Getting Started".
Change to link to "Contributing to Rust" chapter of `rustc` Dev Guide, primarily on the basis that:
* The GitHub "first contribution" Issue "pop-up" says "Be sure to review the [contributing guidelines] and [code of conduct]" and links to this file.
* The "Bug Report" section _seems_ to restrict itself to if "a compiler error message [told] you to come here".
* The previous content of `CONTRIBUTING.md` now lives in the "Contributing to Rust" chapter.
When/if the guide/"Getting Started" section gets revised to not be `rustc`-specific, the choice of linked chapter could be updated.
In the meantime this prevents leading first time contributors into a confusing cul de sac.
_[I wasn't planning to make a PR for this until discussion in #77215 concluded but the discovery that the "first issue" pop-up also links to this document IMO makes it a higher priority to make the link useful sooner rather than later.]_
Related issues:
* https://github.com/rust-lang/rust/issues/77215
* https://github.com/rust-lang/rustc-dev-guide/issues/775#issuecomment-699063082
Fix trait solving ICEs
- Selection candidates that are known to be applicable are preferred
over candidates that are not.
- Don't ICE if a projection/object candidate is no longer applicable
(this can happen due to cycles in normalization)
- Normalize supertraits when finding trait object candidates
Closes#77653Closes#77656
r? `@nikomatsakis`
Make fewer types generic over QueryContext
While trying to refactor `rustc_query_system::query::QueryContext` to make it dyn-safe, I noticed some smaller things:
* QueryConfig doesn't need to be generic over QueryContext
* ~~The `kind` field on QueryJobId is unused~~
* Some unnecessary where clauses
* Many types in `job.rs` where generic over `QueryContext` but only needed `QueryContext::Query`.
If handle_cycle_error() could be refactored to not take `error: CycleError<CTX::Query>`, all those bounds could be removed as well.
Changing `find_cycle_in_stack()` in job.rs to not take a `tcx` argument is the only functional change here. Everything else is just updating type signatures. (aka compile-error driven development ^^)
~~Currently there is a weird bug where memory usage suddenly skyrockets when running UI tests. I'll investigate that tomorrow.
A perf run probably won't make sense before that is fixed.~~
EDIT: `kind` actually is used by `Eq`, and re-adding it fixed the memory issue.
Use `DroplessArena` where we know the type doesn't need drop
This PR uses a single `DroplessArena` in resolve instead of three separate `TypedArena`s.
`DroplessArena` checks that the type indeed doesn't need drop, so in case the types change, this will result in visible failures.
Rollup of 10 pull requests
Successful merges:
- #77420 (Unify const-checking structured errors for `&mut` and `&raw mut`)
- #77554 (Support signed integers and `char` in v0 mangling)
- #77976 (Mark inout asm! operands as used in liveness pass)
- #78009 (Haiku: explicitly set CMAKE_SYSTEM_NAME when cross-compiling)
- #78084 (Greatly improve display for small mobile devices screens)
- #78155 (Fix two small issues in compiler/rustc_lint/src/types.rs)
- #78156 (Fixed build failure of `rustfmt`)
- #78172 (Add test case for #77062)
- #78188 (Add tracking issue number for pin_static_ref)
- #78200 (Add `ControlFlow::is_{break,continue}` methods)
Failed merges:
r? `@ghost`
* compiler docs
* Don't format list as part of a code block
* Clean up some other formatting
* rustdoc book
* Update CommonMark spec version to latest (0.28 -> 0.29)
* Clean up some various wording and formatting
Haiku: explicitly set CMAKE_SYSTEM_NAME when cross-compiling
This resolves issues where the cross-build of LLVM fails because it tries to
link to the host's system libraries instead of the target's system libraries.
Mark inout asm! operands as used in liveness pass
Variables used in `inout` operands in inline assembly (that is, they're used as both input and output to some arbitrary assembly instruction) are being marked as read and written, but are not marked as being used in the RWU table during the liveness pass. This can result in such expressions triggering an unused variable lint warning. This is incorrect behavior- reads without uses are currently only used for compound assignments. We conservatively assume that an `inout` operand is being read and used in the context of the assembly instruction.
Closes#77915
Support signed integers and `char` in v0 mangling
Likely we want more tests, to check the output is correct too: however, I wasn't sure what kind of test we needed, so I just added one similar to that added in https://github.com/rust-lang/rust/pull/77452 for now.
r? @eddyb
Calculate visibilities once in resolve
Then use them through a query based on resolver outputs.
Item visibilities were previously calculated in three places - initially in `rustc_resolve`, then in `rustc_privacy` during type privacy checkin, and then in `rustc_metadata` during metadata encoding.
The visibility logic is not entirely trivial, especially for things like constructors or enum variants, and all of it was duplicated.
This PR deduplicates all the visibility calculations, visibilities are determined once during early name resolution and then stored in `ResolverOutputs` and are later available through `tcx` as a query `tcx.visibility(def_id)`.
(This query existed previously, but only worked for other crates.)
Some special cases (e.g. visibilities for closure types, which are needed for type privacy checking) are not processed in resolve, but deferred and performed directly in the query instead.
Cycles in normalization can cause evaluations to change from Unknown to
Err. This means that some selection that were applicable no longer are.
To avoid this:
* Selection candidates that are known to be applicable are prefered
over candidates that are not.
* We don't ICE if a candidate is no longer applicable.
Rewrite `collect_tokens` implementations to use a flattened buffer
Instead of trying to collect tokens at each depth, we 'flatten' the
stream as we go allong, pushing open/close delimiters to our buffer
just like regular tokens. One capturing is complete, we reconstruct a
nested `TokenTree::Delimited` structure, producing a normal
`TokenStream`.
The reconstructed `TokenStream` is not created immediately - instead, it is
produced on-demand by a closure (wrapped in a new `LazyTokenStream` type). This
closure stores a clone of the original `TokenCursor`, plus a record of the
number of calls to `next()/next_desugared()`. This is sufficient to reconstruct
the tokenstream seen by the callback without storing any additional state. If
the tokenstream is never used (e.g. when a captured `macro_rules!` argument is
never passed to a proc macro), we never actually create a `TokenStream`.
This implementation has a number of advantages over the previous one:
* It is significantly simpler, with no edge cases around capturing the
start/end of a delimited group.
* It can be easily extended to allow replacing tokens an an arbitrary
'depth' by just using `Vec::splice` at the proper position. This is
important for PR #76130, which requires us to track information about
attributes along with tokens.
* The lazy approach to `TokenStream` construction allows us to easily
parse an AST struct, and then decide after the fact whether we need a
`TokenStream`. This will be useful when we start collecting tokens for
`Attribute` - we can discard the `LazyTokenStream` if the parsed
attribute doesn't need tokens (e.g. is a builtin attribute).
The performance impact seems to be neglibile (see
https://github.com/rust-lang/rust/pull/77250#issuecomment-703960604). There is a
small slowdown on a few benchmarks, but it only rises above 1% for incremental
builds, where it represents a larger fraction of the much smaller instruction
count. There a ~1% speedup on a few other incremental benchmarks - my guess is
that the speedups and slowdowns will usually cancel out in practice.
