coverage: Tidy tests and add some new ones by Zalathar · Pull Request #161397 · rust-lang/rust

Zalathar · 2026-08-20T12:47:46Z

While experimenting with some coverage changes, I noticed that some of our tests are not very useful for diagnosing problems, and that we lack good simple tests for some common Rust constructs.

rustbot · 2026-08-20T12:47:51Z

r? @fee1-dead

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Zalathar · 2026-08-20T13:46:23Z

Looks like one of the new tests was affected by #151419, so I added a directive to skip it on older LLVM.

fee1-dead · 2026-08-26T00:44:09Z

Not very familiar with coverage tests :)

@rustbot reroll

These tests are of limited value for investigating specific problems, but still have some worth in detecting regressions by adding variety to the test corpus. (The boundary is a bit fuzzy, but it's easy enough to move tests back out if appropriate.)

rustbot · 2026-09-04T06:26:58Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

Zalathar · 2026-09-05T00:27:08Z

Approved as part of #161517, but landing separately since this is just preliminary test changes.

r? davidtwco
@bors r=davidtwco rollup

rust-bors · 2026-09-05T00:27:11Z

📌 Commit 492fff7 has been approved by davidtwco

It is now in the queue for this repository.

coverage: Tidy tests and add some new ones While experimenting with some coverage changes, I noticed that some of our tests are not very useful for diagnosing problems, and that we lack good simple tests for some common Rust constructs.

Rollup of 14 pull requests Successful merges: - #162324 (miri subtree update) - #162170 (bootstrap: use target's LLVM libdir when cross-compiling) - #158312 (Adds support for AArch64 SVE to inline assembly) - #159792 (A more readable debug map for IndexMaps) - #160745 (make closures act like MaybeDangling) - #161263 (break rustc_expand-rustc_middle dependency) - #161895 (std::sys::pal::sgx: fix mismatched alloc/free alignment) - #161940 (Promote `wasm32-wasip3` to a tier 2 target) - #161397 (coverage: Tidy tests and add some new ones) - #161616 (Report precondition violation for `<usize as SliceIndex>::get_unchecked` in const-eval) - #162248 (Add regression test for unsized const parameter default ICE) - #162250 (Fix hashing of span end columns in incremental compilation) - #162265 (cargotest: add lockfiles) - #162318 (bootstrap: Fix broken path for `./x doc compiler/rustc --open`)

rustbot assigned fee1-dead Aug 20, 2026

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Aug 20, 2026