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

RPITITs inherit method predicates

Browse source
This commit is contained in:
Michael Goulet 2023-06-30 19:09:42 +00:00
parent 982f025cad
commit a14285ca7e
4 changed files with 19 additions and 26 deletions
Download patch file Download diff file Expand all files Collapse all files

16
compiler/rustc_hir_analysis/src/collect/predicates_of.rs
View file

@ -63,7 +63,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen
use rustc_hir::*;
match tcx.opt_rpitit_info(def_id.to_def_id()) {
Some(ImplTraitInTraitData::Trait { opaque_def_id, .. }) => {
Some(ImplTraitInTraitData::Trait { opaque_def_id, fn_def_id }) => {
let opaque_ty_id = tcx.hir().local_def_id_to_hir_id(opaque_def_id.expect_local());
let opaque_ty_node = tcx.hir().get(opaque_ty_id);
let Node::Item(&Item { kind: ItemKind::OpaqueTy(OpaqueTy { lifetime_mapping, .. }), .. }) = opaque_ty_node else {
@ -71,6 +71,18 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen
};
let mut predicates = Vec::new();
// RPITITs should inherit the predicates of their parent. This is
// both to ensure that the RPITITs are only instantiated when the
// parent predicates would hold, and also so that the param-env
// inherits these predicates as assumptions.
let identity_substs = InternalSubsts::identity_for_item(tcx, def_id);
predicates.extend(
tcx.explicit_predicates_of(fn_def_id).instantiate_own(tcx, identity_substs),
);
// We also install bidirectional outlives predicates for the RPITIT
// to keep the duplicates lifetimes from opaque lowering in sync.
compute_bidirectional_outlives_predicates(
tcx,
def_id,
@ -95,7 +107,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen
let impl_assoc_identity_substs = InternalSubsts::identity_for_item(tcx, def_id);
let impl_def_id = tcx.parent(fn_def_id);
let impl_trait_ref_substs =
tcx.impl_trait_ref(impl_def_id).unwrap().skip_binder().substs;
tcx.impl_trait_ref(impl_def_id).unwrap().subst_identity().substs;
let impl_assoc_substs =
impl_assoc_identity_substs.rebase_onto(tcx, impl_def_id, impl_trait_ref_substs);