Implement Chain with Option fuses
The iterators are now "fused" with `Option` so we don't need separate state to track which part is already exhausted, and we may also get niche layout for `None`. We don't use the real `Fuse` adapter because its specialization for `FusedIterator` unconditionally descends into the iterator, and that could be expensive to keep revisiting stuff like nested chains. It also hurts compiler performance to add more iterator layers to `Chain`.
This change was inspired by the [proposal](https://internals.rust-lang.org/t/proposal-implement-iter-chain-using-fuse/12006) on the internals forum. This is an alternate to #70332, directly employing some of the same `Fuse` optimizations as #70366 and #70750.
r? @scottmcm
rustc_codegen_ssa: Refactor construction of linker arguments
And add comments.
This PR doesn't reorder any linker arguments and therefore shouldn't contain any observable changes.
The next goal here is to
- Factor out order-independent linker arguments in the compiler code and in target specifications and pass them together. Such arguments generally apply to the whole linking session or the produced linking result rather to individual object files or libraries.
- Figure out where exactly among the remaining order-dependent arguments we should place customization points like `-C link-args` and `-Z pre-link-args`.
- Possibly provide command line opt-outs for options that are currently passed unconditionally (like CRT objects or arguments defined by the target spec).
- Document and stabilize the customization points that are not yet stable (https://github.com/rust-lang/rust/pull/70505).
save/restore `pessimistic_yield` when entering bodies
This flag is used to make the execution order around `+=` operators
pessimistic. Failure to save/restore the flag was causing independent
async blocks to effect one another, leading to strange ICEs and failed
assumptions.
Fixes#69307
r? @Zoxc
Rollup of 7 pull requests
Successful merges:
- #70134 (add basic support of OsStrExt for HermitCore)
- #70565 (Add inline attributes for functions used in the query system)
- #70828 (rustdoc: Don't try to load source files from external crates)
- #70870 (Fix abuses of tykind::err)
- #70906 (Suggest move for closures and async blocks in more cases.)
- #70912 (Do not suggest adding type param when `use` is already suggested)
- #70930 (add tracking issue to `VecDeque::make_contiguous`)
Failed merges:
r? @ghost
rustdoc: Don't try to load source files from external crates
Local items defined in external macros shouldn't generate rendered source files and should link to the external crate's docs instead.
Part of #70757
r? @GuillaumeGomez
cc @eddyb
add basic support of OsStrExt for HermitCore
- this patch increases the compatibility to other operating systems
- in principle `ffi.rs` is derived from `src/libstd/sys/unix/ext/ffi.rs`
Remove unnecessary TypeFlags::NOMINAL_FLAGS
This was a relic from when we had "nominal flags" and "cached
properties." The latter no longer exists, so nominal flags are no
longer necessary. In fact, every flag is considered a nominal flag. I
went ahead and removed all references to NOMINAL_FLAGS.
Fixes rust-lang#70836
Corrects a typo in rustdoc documentation.
Fixes rust-lang#70856
Sorry, I am just learning git and I think I may have accidentally done some wacky stuff that closed my last PR. Here it is again.
wf: refactor `compute_trait_ref`
moves `extend_cause_with_original_assoc_item_obligation` out of `compute_trait_ref` and
changes `trait_assoc_items` to an iterator. This saves us from building an unnecessary `Vec<_>`
r? @eddyb i guess
ci: move /var/lib/docker to /mnt on GHA
There are some builders that are running out of disk space while building the Docker images, such as arm-android. This moves and symlinks `/var/lib/docker` to the `/mnt` partition on Linux GHA.
Example of a build failing because of this: https://github.com/rust-lang-ci/rust/runs/564628621
remove false positives of unused_braces
fixes#70717
We could potentially be more aggressive when linting let bindings by checking if there are any explicit `ref`s.
I have been unable to create a snippet which compiles when using braces but has a borrowck error
without them. The closes I've gotten is [the following (playground)](https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=4a1552ebe9648cb13fcb8dd969189a6c).
r? @eddyb
This was a relic from when we had "nominal flags" and "cached
properties." The latter no longer exists, so nominal flags are no
longer necessary. In fact, every flag is considered a nominal flag. I
went ahead and removed all references to NOMINAL_FLAGS.
Fixes rust-lang#70836
The iterators are now "fused" with `Option` so we don't need separate
state to track which part is already exhausted, and we may also get
niche layout for `None`. We don't use the real `Fuse` adapter because
its specialization for `FusedIterator` unconditionally descends into the
iterator, and that could be expensive to keep revisiting stuff like
nested chains. It also hurts compiler performance to add more iterator
layers to `Chain`.
Don't import integer and float modules, use assoc consts 2
Follow up to #70777. I missed quite a lot of places. Partially because I wanted to keep the size of the last PR down, and partially because my regexes were not good enough :)
r? @dtolnay
