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Consider arm to diverge if guard diverges #134735

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merged 1 commit into from
Dec 25, 2024

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This is not a fix for #134734, but I discovered it when I was gauging how difficult it would be to fix that. It does fix a really old test though :>

r? @WaffleLapkin or reassign

@rustbot 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 Dec 24, 2024
self.check_expr_has_type_or_error(e, tcx.types.bool, |_| {});

// FIXME: If this is the first arm and the pattern is irrefutable,
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This would be the place to insert a fix for #134734 (it'll need some extra divergence state tracking variable or something), though it also requires some rudimentary heuristic to compute if a pattern is irrefutable in HIR, since that's currently the responsibility of THIR pattern analysis.

@@ -21,9 +21,13 @@ fn d() {
}

fn e() {
// Here the compiler fails to figure out that the `println` is dead.
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Funny that this wasn't a FIXME, but it's obviously a bug.

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@bors r+ rollup

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bors commented Dec 25, 2024

📌 Commit a6a7071 has been approved by WaffleLapkin

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Dec 25, 2024
bors added a commit to rust-lang-ci/rust that referenced this pull request Dec 25, 2024
Rollup of 3 pull requests

Successful merges:

 - rust-lang#134525 (Arbitrary self types v2: unstable doc updates.)
 - rust-lang#134735 (Consider arm to diverge if guard diverges)
 - rust-lang#134741 (Actually print all the relevant parts of a coroutine in verbose mode)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit a247d7b into rust-lang:master Dec 25, 2024
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@rustbot rustbot added this to the 1.85.0 milestone Dec 25, 2024
rust-timer added a commit to rust-lang-ci/rust that referenced this pull request Dec 25, 2024
Rollup merge of rust-lang#134735 - compiler-errors:arm-diverges, r=WaffleLapkin

Consider arm to diverge if guard diverges

This is not a fix for rust-lang#134734, but I discovered it when I was gauging how difficult it would be to fix that. It does fix a really old test though :>

r? `@WaffleLapkin` or reassign
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4 participants