Use module inline assembly to embed bitcode
In LLVM 14, our current method of setting section flags to avoid
embedding the `.llvmbc` section into final compilation artifacts
will no longer work, see issue #90326. The upstream recommendation
is to instead embed the entire bitcode using module-level inline
assembly, which is what this change does.
I've kept the existing code for platforms where we do not need to
set section flags, but possibly we should always be using the
inline asm approach (which would have to look a bit different for MachO).
r? `@nagisa`
rustbot: Add autolabeling for `T-compiler`
This commit adds autolabeling for the `T-compiler` label, for PRs that
modify rustc's source code or tests (currently only `src/test/ui`).
This is possible now that rust-lang/triagebot#1321 has landed.
BTree: improve public descriptions and comments
BTreeSet has always used the term "value" next to and meaning the same thing as "elements" (in the mathematical sense but also used for key-value pairs in BTreeMap), while in the BTreeMap sense these "values" are known as "keys" and definitely not "values". Today I had enough of that.
r? `@Mark-Simulacrum`
Stabilize `ControlFlow::{is_break, is_continue}`
The type itself was stabilized in 1.55, but using it is not ergonomic without these helper functions. Stabilize them.
r? rust-lang/libs-api
This commit adds autolabeling for the `T-compiler` label, for PRs that
modify rustc's source code or tests (currently only `src/test/ui`).
This is possible now that rust-lang/triagebot#1321 has landed.
replace dynamic library module with libloading
This PR deletes the `rustc_metadata::dynamic_lib` module in favor of the popular and better tested [`libloading` crate](https://github.com/nagisa/rust_libloading/).
We don't benefit from `libloading`'s symbol lifetimes since we end up leaking the loaded library in all cases, but the call-sites look much nicer by improving error handling and abstracting away some transmutes. We also can remove `rustc_metadata`'s direct dependencies on `libc` and `winapi`.
This PR also adds an exception for `libloading` (and its license) to tidy, so this will need sign-off from the compiler team.
Stabilise `feature(const_generics_defaults)`
`feature(const_generics_defaults)` is complete implementation wise and has a pretty extensive test suite so I think is ready for stabilisation.
needs stabilisation report and maybe an RFC 😅
r? `@lcnr`
cc `@rust-lang/project-const-generics`
rustbot: Add autolabeling for `T-rustdoc`
This commit adds autolabeling for the `T-rustdoc` label, for PRs that
modify rustdoc's source code, tests, or internal tooling.
This is possible now that rust-lang/triagebot#1321 has landed.
bootstrap: Change unwrap() to expect() for WIX path
On Windows, `x.py dist` command panics without proper error message if `WIX` environment variable is not set. This patch changes `Option::unwrap()` to `Option::expect()`.
Btree: assert more API compatibility
Introducing a member such as `BTreeSet::min()` would silently break compatibility if no code calls the existing `BTreeSet::min(set)`. `BTreeSet` is the only btree class silently bringing in stable members, apart from many occurrences of `#[derive(Debug)]` on iterators.
r? `@Mark-Simulacrum`
Slightly optimize hash map stable hashing
I was profiling some of the `rustc-perf` benchmarks locally and noticed that quite some time is spent inside the stable hash of hashmaps. I tried to use a `SmallVec` instead of a `Vec` there, which helped very slightly.
Then I tried to remove the sorting, which was a bottleneck, and replaced it with insertion into a binary heap. Locally, it yielded nice improvements in instruction counts and RSS in several benchmarks for incremental builds. The implementation could probably be much nicer and possibly extended to other stable hashes, but first I wanted to test the perf impact properly.
Can I ask someone to do a perf run? Thank you!
Rollup of 8 pull requests
Successful merges:
- #90081 (Make `intrinsics::write_bytes` const)
- #91643 (asm: Allow using r9 (ARM) and x18 (AArch64) if they are not reserved by the current target)
- #91737 (Make certain panicky stdlib functions behave better under panic_immediate_abort)
- #91750 (rustdoc: Add regression test for Iterator as notable trait on &T)
- #91764 (Do not ICE when suggesting elided lifetimes on non-existent spans.)
- #91780 (Remove hir::Node::hir_id.)
- #91797 (Fix zero-sized reference to deallocated memory)
- #91806 (Make `Unique`s methods `const`)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
This commit adds autolabeling for the `T-rustdoc` label, for PRs that
modify rustdoc's source code, tests, or internal tooling.
This is possible now that rust-lang/triagebot#1321 has landed.
rustdoc: Add regression test for Iterator as notable trait on &T
Closes#78160
This regression test is different from the one in #91748, because while neither of these function should have Iterator marked as a notable trait, the reasons are different.
* In this PR, it returns `&T where T: Iterator`. The `mut` is what's missing.
* In #91748, it returns `&mut T`. The trait bounds are what's missing.
Make certain panicky stdlib functions behave better under panic_immediate_abort
The stdlib has a `panic_immediate_abort` feature that turns panics into immediate aborts, without any formatting/display logic. This feature was [introduced](https://github.com/rust-lang/rust/pull/55011) primarily for codesize-constrained situations.
Unfortunately, this win doesn't quite propagate to `Result::expect()` and `Result::unwrap()`, while the formatting machinery is reduced, `expect()` and `unwrap()` both call `unwrap_failed("msg", &err)` which has a signature of `fn unwrap_failed(msg: &str, error: &dyn fmt::Debug)` and is `#[inline(never)]`. This means that `unwrap_failed` will unconditionally construct a `dyn Debug` trait object even though the object is never used in the function.
Constructing a trait object (even if you never call a method on it!) forces rust to include the vtable and any dependencies. This means that in `panic_immediate_abort` mode, calling expect/unwrap on a Result will pull in a whole bunch of formatting code for the error type even if it's completely unused.
This PR swaps out the function with one that won't require a trait object such that it won't force the inclusion of vtables in the code. It also gates off `#[inline(never)]` in a bunch of other places where allowing the inlining of an abort may be useful (this kind of thing is already done elsewhere in the stdlib).
I don't know how to write a test for this; we don't really seem to have any tests for `panic_immediate_abort` anyway so perhaps it's fine as is.
asm: Allow using r9 (ARM) and x18 (AArch64) if they are not reserved by the current target
This supersedes https://github.com/rust-lang/rust/pull/88879.
cc `@Skirmisher`
r? `@joshtriplett`
