diff options
| -rw-r--r-- | compiler/rustc_mir_build/src/build/matches/mod.rs | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/compiler/rustc_mir_build/src/build/matches/mod.rs b/compiler/rustc_mir_build/src/build/matches/mod.rs index a67c59138cd..a5f24ba3e5b 100644 --- a/compiler/rustc_mir_build/src/build/matches/mod.rs +++ b/compiler/rustc_mir_build/src/build/matches/mod.rs @@ -1585,18 +1585,23 @@ impl<'a, 'tcx> Builder<'a, 'tcx> { // We could add them to the or-candidates before the call to `test_or_pattern` but this // would make it impossible to detect simplifiable or-patterns. That would guarantee // exponentially large CFGs for cases like `(1 | 2, 3 | 4, ...)`. + let mut last_otherwise = None; + first_candidate.visit_leaves(|leaf_candidate| { + last_otherwise = leaf_candidate.otherwise_block; + }); first_candidate.visit_leaves(|leaf_candidate| { assert!(leaf_candidate.match_pairs.is_empty()); leaf_candidate.match_pairs.extend(remaining_match_pairs.iter().cloned()); let or_start = leaf_candidate.pre_binding_block.unwrap(); // In a case like `(P | Q, R | S)`, if `P` succeeds and `R | S` fails, we know `(Q, // R | S)` will fail too. If there is no guard, we skip testing of `Q` by branching - // directly to `remainder_start`. If there is a guard, `or_otherwise` can be reached - // by guard failure as well, so we can't skip `Q`. + // directly to `last_otherwise`. If there is a guard, + // `leaf_candidate.otherwise_block` can be reached by guard failure as well, so we + // can't skip `Q`. let or_otherwise = if leaf_candidate.has_guard { leaf_candidate.otherwise_block.unwrap() } else { - remainder_start + last_otherwise.unwrap() }; self.test_candidates_with_or( span, |