Account for C string literals and `format_args` in `HiddenUnicodeCodepoints` lint
This is stacked on #134955, and either that can land first or both of them can land together here. I split this out because this is a bit more involved of an impl.
Fixes#94945
compiler: Add a statement-of-intent to `rustc_abi`
This just documents the most basic idea of what the crate is even for in my view, rather than leaving that strewn about GitHub issues, PR reviews, and Zulip streams. In particular, I hope to make it clearer what code should go in `rustc_abi` and what should not, which is of immediate relevance to contributors.
I considered going even further and explaining ideas like "ABI compatibility", prologues, and so on. However, because of the cross-cutting nature of ABI, I think such explanations should probably live in the place for cross-cutting documents: the rustc dev guide. This is only meant to be a quick "by the way".
explicitly set float ABI for all ARM targets
We currently always set the `FloatABIType` field in the LLVM target machine to `Default`, which means LLVM infers the ARM float ABI (hard vs soft) from the LLVM target triple. This causes problems such as having to set the LLVM triple to `*-gnueabi` for our `musleabi` targets to ensure they get correctly inferred as soft-float targets. It also means rustc doesn't really know which float ABI ends up being used, which is a blocker for https://github.com/rust-lang/rust/pull/134794. So I think we should stop doing that and instead explicitly control that value. That's what this PR implements.
See [Zulip](https://rust-lang.zulipchat.com/#narrow/channel/187780-t-compiler.2Fwg-llvm/topic/Softfloat.20ABI.2C.20hardfloat.20instructions) for more context.
Best reviewed commit-by-commit. I hope I got all those `llvm_floatabi` values right...
stabilize const_swap
libs-api FCP passed in https://github.com/rust-lang/rust/issues/83163.
However, I only just realized that this actually involves an intrinsic. The intrinsic could be implemented entirely with existing stable const functionality, but we choose to make it a primitive to be able to detect more UB. So nominating for `@rust-lang/lang` to make sure they are aware; I leave it up to them whether they want to FCP this.
While at it I also renamed the intrinsic to make the "nonoverlapping" constraint more clear.
Fixes#83163
A couple datalog/borrowck cleanups
As discussed on zulip, here's a chill one in between slightly more interesting PRs:
- I hadn't noticed there still were a couple of datalog-related modules outside of their dedicated `polonius` module (go to horn-clause jail, bonk!).
- there somehow was both a `diags` module and a `diagnostics` module.
- a couple other tiny things being renamed -- let me know what you think.
As requested I've tried to have somewhat granular commits to ease review, but the last two or three could be squashed together, since they're all related to the `diags` module (but moving its contents is less tedious to check in its own commit).
r? `@jackh726`
rustc_codegen_ssa: Buffer file writes in link_rlib
This makes this step take ~25ms on my machine (M3 Max 64GB) for Zed repo instead of ~150ms (on editor crate). Additionally it takes down the time needed for a clean cargo build of ripgrep from ~6.1s to 5.9s.
This change is mostly relevant for dev builds of crates with multiple large CGUs.
I imagine it could be quite relevant for dev scenarios on Windows, but sadly I have no way to measure that myself.
Compute liveness constraints in location-sensitive polonius
This continues the location-sensitive prototype. In this episode, we build the liveness constraints.
Reminder of the approach we're taking: we need variance data to create liveness edges in the forward/backward/both directions (respectively in the cases of covariance, contravariance, invariance) in the localized constraint graph.
This PR:
- introduces the holder for that, and for the liveness data in the correct shape: the transpose of what we're using today, "live regions per points".
- records use/drop live region variance during tracing
- records regular live region variance at the end of liveness
- records the correctly shaped live region per point matrix
- uses all of the above to compute the liveness constraints
(There's still technically one tiny part of the liveness owl left to do, but I'll leave it for a future PR: we also need to disable the NLL optimization that avoids computing liveness for locals whose types contain a region outliving a free region -- the existing constraints make it effectively live at all points; this doesn't work under polonius)
r? `@jackh726` cc `@matthewjasper`
Rollup of 4 pull requests
Successful merges:
- #134870 (Fix sentence fragment in `pin` module docs)
- #134884 (Fix typos)
- #134892 (Added codegen test for elidings bounds check when indexes are manually checked)
- #134894 (Document how to run the split Docker pipelines)
r? `@ghost`
`@rustbot` modify labels: rollup
Improve default target options for x86_64-unknown-linux-none
Without a standard library, we cannot unwind, so it should be panic=abort by default.
Additionally, it does not have std because while it is Linux, it cannot use libc, which std uses today for Linux.
Using PIE by default may be surprising to users, as shown in #134763, so I've documented it explicitly. I'm not sure if we want to count that as fixing the issue or not.
cc `@morr0ne,` as you added the target (and are the maintainer), and `@Noratrieb,` who reviewed that PR (:D).
- add a FIXME when looking for the region variance of unexpected regions
- drive-by: fix a doc comment link
- drive-by: simplify the variance match using exported variants instead
This context struct will hold data to help creating localized
constraints:
- the live regions, with the shape matching a CFG walk, indexed per
point
- the variance of these live regions, represented as the direction we'll
add the appropriate
We also add this structure to the mir typeck to record liveness data,
and make it responsible for localized constraint creation.
Avoid ICE in borrowck
Provide a fallback in `best_blame_constraint` when `find_constraint_paths_between_regions` doesn't have a result. This code is due a rework to avoid the letf-over `unwrap()`, but avoids the ICE caused by the repro.
Fix#133252.
