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Deny floats even when adt_const_params is enabled

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This commit is contained in:
Michael Goulet 2022-07-04 23:44:41 +00:00
parent c396bb3b8a
commit a1634642e0
7 changed files with 135 additions and 66 deletions
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22
compiler/rustc_trait_selection/src/traits/structural_match.rs
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@ -26,6 +26,7 @@ pub enum NonStructuralMatchTyKind<'tcx> {
Closure,
Generator,
Projection,
Float,
}
/// This method traverses the structure of `ty`, trying to find an
@ -53,12 +54,16 @@ pub enum NonStructuralMatchTyKind<'tcx> {
/// For more background on why Rust has this requirement, and issues
/// that arose when the requirement was not enforced completely, see
/// Rust RFC 1445, rust-lang/rust#61188, and rust-lang/rust#62307.
///
/// The floats_allowed flag is used to deny constants in floating point
pub fn search_for_structural_match_violation<'tcx>(
span: Span,
tcx: TyCtxt<'tcx>,
ty: Ty<'tcx>,
floats_allowed: bool,
) -> Option<NonStructuralMatchTy<'tcx>> {
ty.visit_with(&mut Search { tcx, span, seen: FxHashSet::default() }).break_value()
ty.visit_with(&mut Search { tcx, span, seen: FxHashSet::default(), floats_allowed })
.break_value()
}
/// This method returns true if and only if `adt_ty` itself has been marked as
@ -119,6 +124,8 @@ struct Search<'tcx> {
/// Tracks ADTs previously encountered during search, so that
/// we will not recur on them again.
seen: FxHashSet<hir::def_id::DefId>,
floats_allowed: bool,
}
impl<'tcx> Search<'tcx> {
@ -192,13 +199,24 @@ impl<'tcx> TypeVisitor<'tcx> for Search<'tcx> {
// for empty array.
return ControlFlow::CONTINUE;
}
ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::Str | ty::Never => {
ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::Str | ty::Never => {
// These primitive types are always structural match.
//
// `Never` is kind of special here, but as it is not inhabitable, this should be fine.
return ControlFlow::CONTINUE;
}
ty::Float(_) => {
if self.floats_allowed {
return ControlFlow::CONTINUE;
} else {
return ControlFlow::Break(NonStructuralMatchTy {
ty,
kind: NonStructuralMatchTyKind::Float,
});
}
}
ty::Array(..) | ty::Slice(_) | ty::Ref(..) | ty::Tuple(..) => {
// First check all contained types and then tell the caller to continue searching.
return ty.super_visit_with(self);