diff options
Diffstat (limited to 'compiler/rustc_pattern_analysis/src')
| -rw-r--r-- | compiler/rustc_pattern_analysis/src/usefulness.rs | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/compiler/rustc_pattern_analysis/src/usefulness.rs b/compiler/rustc_pattern_analysis/src/usefulness.rs index 6535afcc398..814559a66c5 100644 --- a/compiler/rustc_pattern_analysis/src/usefulness.rs +++ b/compiler/rustc_pattern_analysis/src/usefulness.rs @@ -951,7 +951,11 @@ impl<Cx: PatCx> PlaceInfo<Cx> { self.is_scrutinee && matches!(ctors_for_ty, ConstructorSet::NoConstructors); // Whether empty patterns are counted as useful or not. We only warn an empty arm unreachable if // it is guaranteed unreachable by the opsem (i.e. if the place is `known_valid`). - let empty_arms_are_unreachable = self.validity.is_known_valid(); + // We don't want to warn empty patterns as unreachable by default just yet. We will in a + // later version of rust or under a different lint name, see + // https://github.com/rust-lang/rust/pull/129103. + let empty_arms_are_unreachable = self.validity.is_known_valid() + && (is_toplevel_exception || cx.is_exhaustive_patterns_feature_on()); // Whether empty patterns can be omitted for exhaustiveness. We ignore place validity in the // toplevel exception and `exhaustive_patterns` cases for backwards compatibility. let can_omit_empty_arms = self.validity.is_known_valid() |