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Update comment about where Ty:

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We no longer move trait predicates where the self ty is a ty param to
"the bounds of a ty param".
This commit is contained in:
León Orell Valerian Liehr 2025-06-18 17:02:51 +02:00
parent 10d7e5faf2
commit 9788f59bbf
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1 changed files with 6 additions and 10 deletions
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16
compiler/rustc_hir_analysis/src/collect/predicates_of.rs
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@ -267,20 +267,16 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen
match predicate.kind {
hir::WherePredicateKind::BoundPredicate(bound_pred) => {
let ty = icx.lowerer().lower_ty_maybe_return_type_notation(bound_pred.bounded_ty);
let bound_vars = tcx.late_bound_vars(predicate.hir_id);
// Keep the type around in a dummy predicate, in case of no bounds.
// That way, `where Ty:` is not a complete noop (see #53696) and `Ty`
// is still checked for WF.
// This is a `where Ty:` (sic!).
if bound_pred.bounds.is_empty() {
if let ty::Param(_) = ty.kind() {
// This is a `where T:`, which can be in the HIR from the
// transformation that moves `?Sized` to `T`'s declaration.
// We can skip the predicate because type parameters are
// trivially WF, but also we *should*, to avoid exposing
// users who never wrote `where Type:,` themselves, to
// compiler/tooling bugs from not handling WF predicates.
// We can skip the predicate because type parameters are trivially WF.
} else {
// Keep the type around in a dummy predicate. That way, it's not a complete
// noop (see #53696) and `Ty` is still checked for WF.
let span = bound_pred.bounded_ty.span;
let predicate = ty::Binder::bind_with_vars(
ty::ClauseKind::WellFormed(ty.into()),