diff options
Diffstat (limited to 'compiler/rustc_pattern_analysis/src/usefulness.rs')
| -rw-r--r-- | compiler/rustc_pattern_analysis/src/usefulness.rs | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/compiler/rustc_pattern_analysis/src/usefulness.rs b/compiler/rustc_pattern_analysis/src/usefulness.rs index b1c646e9884..19446a1efe9 100644 --- a/compiler/rustc_pattern_analysis/src/usefulness.rs +++ b/compiler/rustc_pattern_analysis/src/usefulness.rs @@ -994,7 +994,8 @@ impl<Cx: PatCx> PlaceInfo<Cx> { if !missing_ctors.is_empty() && !report_individual_missing_ctors { // Report `_` as missing. missing_ctors = vec![Constructor::Wildcard]; - } else if missing_ctors.iter().any(|c| c.is_non_exhaustive()) { + } else if missing_ctors.iter().any(|c| c.is_non_exhaustive()) && !cx.exhaustive_witnesses() + { // We need to report a `_` anyway, so listing other constructors would be redundant. // `NonExhaustive` is displayed as `_` just like `Wildcard`, but it will be picked // up by diagnostics to add a note about why `_` is required here. @@ -1747,7 +1748,9 @@ fn compute_exhaustiveness_and_usefulness<'a, 'p, Cx: PatCx>( // `ctor` is *irrelevant* if there's another constructor in `split_ctors` that matches // strictly fewer rows. In that case we can sometimes skip it. See the top of the file for // details. - let ctor_is_relevant = matches!(ctor, Constructor::Missing) || missing_ctors.is_empty(); + let ctor_is_relevant = matches!(ctor, Constructor::Missing) + || missing_ctors.is_empty() + || mcx.tycx.exhaustive_witnesses(); let mut spec_matrix = matrix.specialize_constructor(pcx, &ctor, ctor_is_relevant)?; let mut witnesses = ensure_sufficient_stack(|| { compute_exhaustiveness_and_usefulness(mcx, &mut spec_matrix) |