diff --git a/compiler/rustc_pattern_analysis/src/constructor.rs b/compiler/rustc_pattern_analysis/src/constructor.rs index e94a0373c79ff..269c48bca054f 100644 --- a/compiler/rustc_pattern_analysis/src/constructor.rs +++ b/compiler/rustc_pattern_analysis/src/constructor.rs @@ -733,12 +733,17 @@ impl Constructor { /// this checks for inclusion. // We inline because this has a single call site in `Matrix::specialize_constructor`. #[inline] - pub(crate) fn is_covered_by(&self, pcx: &PlaceCtxt<'_, Cx>, other: &Self) -> bool { - match (self, other) { - (Wildcard, _) => pcx - .mcx - .tycx - .bug(format_args!("Constructor splitting should not have returned `Wildcard`")), + pub(crate) fn is_covered_by( + &self, + pcx: &PlaceCtxt<'_, Cx>, + other: &Self, + ) -> Result { + Ok(match (self, other) { + (Wildcard, _) => { + return Err(pcx.mcx.tycx.bug(format_args!( + "Constructor splitting should not have returned `Wildcard`" + ))); + } // Wildcards cover anything (_, Wildcard) => true, // Only a wildcard pattern can match these special constructors. @@ -779,10 +784,12 @@ impl Constructor { (Opaque(self_id), Opaque(other_id)) => self_id == other_id, (Opaque(..), _) | (_, Opaque(..)) => false, - _ => pcx.mcx.tycx.bug(format_args!( - "trying to compare incompatible constructors {self:?} and {other:?}" - )), - } + _ => { + return Err(pcx.mcx.tycx.bug(format_args!( + "trying to compare incompatible constructors {self:?} and {other:?}" + ))); + } + }) } } diff --git a/compiler/rustc_pattern_analysis/src/lib.rs b/compiler/rustc_pattern_analysis/src/lib.rs index 6374874165fc1..5f978e6ccd24a 100644 --- a/compiler/rustc_pattern_analysis/src/lib.rs +++ b/compiler/rustc_pattern_analysis/src/lib.rs @@ -121,7 +121,7 @@ pub trait TypeCx: Sized + fmt::Debug { ) -> fmt::Result; /// Raise a bug. - fn bug(&self, fmt: fmt::Arguments<'_>) -> !; + fn bug(&self, fmt: fmt::Arguments<'_>) -> Self::Error; /// Lint that the range `pat` overlapped with all the ranges in `overlaps_with`, where the range /// they overlapped over is `overlaps_on`. We only detect singleton overlaps. diff --git a/compiler/rustc_pattern_analysis/src/lints.rs b/compiler/rustc_pattern_analysis/src/lints.rs index 4bfe7dfb072c4..d68664a231b8f 100644 --- a/compiler/rustc_pattern_analysis/src/lints.rs +++ b/compiler/rustc_pattern_analysis/src/lints.rs @@ -80,7 +80,7 @@ impl<'p, 'tcx> PatternColumn<'p, 'tcx> { let mut specialized_columns: Vec<_> = (0..arity).map(|_| Self { patterns: Vec::new() }).collect(); let relevant_patterns = - self.patterns.iter().filter(|pat| ctor.is_covered_by(pcx, pat.ctor())); + self.patterns.iter().filter(|pat| ctor.is_covered_by(pcx, pat.ctor()).unwrap_or(false)); for pat in relevant_patterns { let specialized = pat.specialize(ctor, arity); for (subpat, column) in specialized.into_iter().zip(&mut specialized_columns) { diff --git a/compiler/rustc_pattern_analysis/src/rustc.rs b/compiler/rustc_pattern_analysis/src/rustc.rs index ef90d24b0bf1e..e635f23c81418 100644 --- a/compiler/rustc_pattern_analysis/src/rustc.rs +++ b/compiler/rustc_pattern_analysis/src/rustc.rs @@ -901,7 +901,7 @@ impl<'p, 'tcx> TypeCx for RustcMatchCheckCtxt<'p, 'tcx> { Ok(()) } - fn bug(&self, fmt: fmt::Arguments<'_>) -> ! { + fn bug(&self, fmt: fmt::Arguments<'_>) -> Self::Error { span_bug!(self.scrut_span, "{}", fmt) } diff --git a/compiler/rustc_pattern_analysis/src/usefulness.rs b/compiler/rustc_pattern_analysis/src/usefulness.rs index a627bdeef81e3..b7224ea516062 100644 --- a/compiler/rustc_pattern_analysis/src/usefulness.rs +++ b/compiler/rustc_pattern_analysis/src/usefulness.rs @@ -1059,7 +1059,7 @@ impl<'p, Cx: TypeCx> Matrix<'p, Cx> { pcx: &PlaceCtxt<'_, Cx>, ctor: &Constructor, ctor_is_relevant: bool, - ) -> Matrix<'p, Cx> { + ) -> Result, Cx::Error> { let ctor_sub_tys = pcx.ctor_sub_tys(ctor); let arity = ctor_sub_tys.len(); let specialized_place_ty = ctor_sub_tys.chain(self.place_ty[1..].iter().cloned()).collect(); @@ -1075,12 +1075,12 @@ impl<'p, Cx: TypeCx> Matrix<'p, Cx> { wildcard_row_is_relevant: self.wildcard_row_is_relevant && ctor_is_relevant, }; for (i, row) in self.rows().enumerate() { - if ctor.is_covered_by(pcx, row.head().ctor()) { + if ctor.is_covered_by(pcx, row.head().ctor())? { let new_row = row.pop_head_constructor(ctor, arity, ctor_is_relevant, i); matrix.expand_and_push(new_row); } } - matrix + Ok(matrix) } } @@ -1490,7 +1490,7 @@ fn compute_exhaustiveness_and_usefulness<'a, 'p, Cx: TypeCx>( // 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 mut spec_matrix = matrix.specialize_constructor(pcx, &ctor, ctor_is_relevant); + 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, false) })?;