Implement `-Z allow-partial-mitigations` (RFC 3855)
This implements `-Z allow-partial-mitigations` as an unstable option, currently with support for control-flow-guard and stack-protector.
As a difference from the RFC, we have `-Z allow-partial-mitigations=!foo` rather than `-Z deny-partial-mitigations=foo`, since I couldn't find an easy way to have an allow/deny pair of flags where the latter flag wins.
To allow for stabilization, this is only enabled starting from the next edition. Maybe a better policy is possible (bikeshed).
r? @rcvalle
Use closures more consistently in `dep_graph.rs`.
This file has several methods that take a `FnOnce() -> R` closure:
- `DepGraph::with_ignore`
- `DepGraph::with_query_deserialization`
- `DepGraph::with_anon_task`
- `DepGraphData::with_anon_task_inner`
It also has two methods that take a faux closure via an `A` argument and a `fn(TyCtxt<'tcx>, A) -> R` argument:
- DepGraph::with_task
- DepGraphData::with_task
The rationale is that the faux closure exercises tight control over what state they have access to. This seems silly when (a) they are passed a `TyCtxt`, and (b) when similar nearby functions take real closures. And they are more awkward to use, e.g. requiring multiple arguments to be gathered into a tuple. This commit changes the faux closures to real closures.
r? @Zalathar
Deprioritize doc(hidden) re-exports in diagnostic paths
Fixesrust-lang/rust#153477.
This is the other half of rust-lang/rust#99698, which fixed the case where the *parent module* is `#[doc(hidden)]` but left the case where the re-export itself is `#[doc(hidden)]` as a FIXME (with a tracking test in `dont-suggest-doc-hidden-variant-for-enum/hidden-child.rs`).
The problem: when a crate does `#[doc(hidden)] pub use core::error::Error`, diagnostics pick up the hidden re-export path instead of the canonical one. For example, `snafu::Error` instead of `std::error::Error`.
Two changes:
In `visible_parent_map`, the `add_child` closure now checks whether the re-export itself is `#[doc(hidden)]` via `reexport_chain` and sends it to `fallback_map`, same treatment as doc-hidden parents and underscore re-exports.
`should_encode_attrs` now returns `true` for `DefKind::Use`. Without this, `#[doc(hidden)]` on `use` items was never written to crate metadata, so `is_doc_hidden` always returned `false` cross-crate. This was the actual root cause, the check in `visible_parent_map` alone isn't enough if the attribute isn't in the metadata.
The existing FIXME test now serves as the regression test. The `.stderr` goes from suggesting `hidden_child::__private::Some(1i32)` to just `Some(1i32)`.
cc @eggyal
Post-attribute ports cleanup pt. 1
r? @jdonszelmann
This cleans up some checks I could find were for non-parsed attributes, and works towards removing BUILTIN_ATTRIBUTES
All commits do one thing and every commit passes tests, so best reviewed commit by commit
This implements `-Z allow-partial-mitigations` as an unstable option,
currently with support for control-flow-guard and stack-protector.
As a difference from the RFC, we have `-Z allow-partial-mitigations=!foo`
rather than `-Z deny-partial-mitigations=foo`, since I couldn't find an easy
way to have an allow/deny pair of flags where the latter flag wins.
To allow for stabilization, this is only enabled starting from the next edition. Maybe a
better policy is possible (bikeshed).
This file has several methods that take a `FnOnce() -> R` closure:
- `DepGraph::with_ignore`
- `DepGraph::with_query_deserialization`
- `DepGraph::with_anon_task`
- `DepGraphData::with_anon_task_inner`
It also has two methods that take a faux closure via an `A` argument and
a `fn(TyCtxt<'tcx>, A) -> R` argument:
- DepGraph::with_task
- DepGraphData::with_task
The rationale is that the faux closure exercises tight control over what
state they have access to. This seems silly when (a) they are passed a
`TyCtxt`, and (b) when similar nearby functions take real closures. And
they are more awkward to use, e.g. requiring multiple arguments to be
gathered into a tuple. This commit changes the faux closures to real
closures.
Link LLVM dynamically on aarch64-apple-darwin
Follow-up to rust-lang/rust#152768.
* Link LLVM dynamically on MacOS
* Fix a macOS LLVM dylib name mismatch
Rename `target.abi` to `target.cfg_abi` and enum-ify llvm_abiname
See [Zulip](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/De-spaghettifying.20ABI.20controls/with/578893542) for more context. Discussed a bit in https://github.com/rust-lang/rust/pull/153769#discussion_r2934399038 too.
This renames `target.abi` to `target.cfg_abi` to make it less likely that someone will use it to determine things about the actual ccABI, i.e. the calling convention used on the target. `target.abi` does not control that calling convention, it just *sometimes* informs the user about that calling convention (and also about other aspects of the ABI).
Also turn llvm_abiname into an enum to make it more natural to match on.
Cc @workingjubilee @madsmtm
Optimize dependency file search
I tried to look into the slowdown reported in https://github.com/rust-lang/cargo/issues/16665.
I created a Rust hello world program, and used this Python script to create a directory containing 200k files:
```python
from pathlib import Path
dir = Path("deps")
dir.mkdir(parents=True, exist_ok=True)
for i in range(200000):
path = dir / f"file{i:07}.o"
with open(path, "w") as f:
f.write("\n")
```
Then I tried to do various small microoptimalizations and simplifications to the code that iterates the search directories. Each individual commit improved performance, with the third one having the biggest effect.
Here are the results on `main` vs the last commit with the stage1 compiler on Linux, using `hyperfine "rustc +stage1 src/main.rs -L deps" -r 30` (there's IO involved, so it's good to let it run for a while):
```bash
Benchmark 1: rustc +stage1 src/main.rs -L deps
Time (mean ± σ): 299.4 ms ± 2.7 ms [User: 161.9 ms, System: 144.9 ms]
Range (min … max): 294.8 ms … 307.1 ms 30 runs
Benchmark 1: rustc +stage1 src/main.rs -L deps
Time (mean ± σ): 208.1 ms ± 4.5 ms [User: 87.3 ms, System: 128.7 ms]
Range (min … max): 202.4 ms … 219.6 ms 30 runs
```
Would be cool if someone could try this on macOS (maybe @ehuss - not sure if you have macOS or you only commented about its behavior on the Cargo issue :) ).
I also tried to prefilter the paths (not in this PR); right now we load everything and then we filter files with given prefixes, that's wasteful. Filtering just files starting with `lib` would get us down to ~150ms here. (The baseline without `-L` is ~80ms on my PC). The rest of the 70ms is essentially allocations from iterating the directory entries and sorting. That would be very hard to change - iterating the directory entries (de)allocates a lot of intermediate paths :( We'd have to implement the iteration by hand with either arena allocation, or at least some better management of memory.
r? @nnethercote
refactor(mgca): Change `DefKind::Const` and `DefKind::AssocConst` to have a `is_type_const` flag
Addresses rust-lang/rust#152940
- Changed `DefKind::Const` and `DefKind::AssocConst` to have a `is_type_const` flag.
- changed `is_type_const` query to check for this flag
- removed `is_rhs_type_const` query
r? @BoxyUwU
* refactor: add `is_type_const` flag to `DefKind::Const` and `AssocConst`
* refactor(cleanup) remove the `rhs_is_type_const` query
* style: fix formatting
* refactor: refactor stuff in librustdoc for new Const and AssocConst
* refactor: refactor clippy for the changes
* chore: formatting
* fix: fix test
* fix: fix suggestions
* Update context.rs
Co-authored-by: Boxy <rust@boxyuwu.dev>
* changed AssocKind::Const to store data about being a type const
It was removed in #115920 to enable it being moved to
`rustc_query_system`, a move that has recently been reversed. It's much
simpler as an enum.
Also:
- Remove the overly complicated `Debug` impl for `DepKind`.
- Remove the trivial `DepKind` associated constants (`NULL` et al.)
- Add an assertion to ensure that the number of `DepKinds` fits within a
`u16`.
- Rename `DEP_KIND_VARIANTS` as `DEP_KIND_NUM_VARIANTS`, to make it
clearer that it's a count, not a collection.
- Use `stringify!` in one place to make the code clearer.
Jacob Pratt