bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Deny RPITIT for object safety

Browse source
This commit is contained in:
Michael Goulet 2022-09-11 09:13:55 +00:00
parent 1463688700
commit 89b6488ef0
4 changed files with 107 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

26
compiler/rustc_trait_selection/src/traits/object_safety.rs
View file

@ -13,6 +13,7 @@ use super::elaborate_predicates;
use crate::infer::TyCtxtInferExt;
use crate::traits::query::evaluate_obligation::InferCtxtExt;
use crate::traits::{self, Obligation, ObligationCause};
use hir::def::DefKind;
use rustc_errors::{FatalError, MultiSpan};
use rustc_hir as hir;
use rustc_hir::def_id::DefId;
@ -431,6 +432,9 @@ fn virtual_call_violation_for_method<'tcx>(
if contains_illegal_self_type_reference(tcx, trait_def_id, sig.output()) {
return Some(MethodViolationCode::ReferencesSelfOutput);
}
if contains_illegal_impl_trait_in_trait(tcx, sig.output()) {
return Some(MethodViolationCode::ReferencesImplTraitInTrait);
}
// We can't monomorphize things like `fn foo<A>(...)`.
let own_counts = tcx.generics_of(method.def_id).own_counts();
@ -793,6 +797,12 @@ fn contains_illegal_self_type_reference<'tcx, T: TypeVisitable<'tcx>>(
ControlFlow::CONTINUE
}
}
ty::Projection(ref data)
if self.tcx.def_kind(data.item_def_id) == DefKind::ImplTraitPlaceholder =>
{
// We'll deny these later in their own pass
ControlFlow::CONTINUE
}
ty::Projection(ref data) => {
// This is a projected type `<Foo as SomeTrait>::X`.
@ -861,6 +871,22 @@ fn contains_illegal_self_type_reference<'tcx, T: TypeVisitable<'tcx>>(
.is_break()
}
pub fn contains_illegal_impl_trait_in_trait<'tcx>(
tcx: TyCtxt<'tcx>,
ty: ty::Binder<'tcx, Ty<'tcx>>,
) -> bool {
// FIXME(RPITIT): Perhaps we should use a visitor here?
ty.skip_binder().walk().any(|arg| {
if let ty::GenericArgKind::Type(ty) = arg.unpack()
&& let ty::Projection(proj) = ty.kind()
{
tcx.def_kind(proj.item_def_id) == DefKind::ImplTraitPlaceholder
} else {
false
}
})
}
pub fn provide(providers: &mut ty::query::Providers) {
*providers = ty::query::Providers { object_safety_violations, ..*providers };
}