Auto merge of #107038 - compiler-errors:dont-wfcheck-non-local-rpit, r=oli-obk

Don't wf-check non-local RPITs

We were using `ty::is_impl_trait_defn(..).is_none()` to check if we need to add WF obligations for an opaque type.

This is *supposed* to be checking if the type is a TAIT, since RPITs' wfness is implied by wf checking its parent item, but since `is_impl_trait_defn` returns `None` for non-local RPIT and async futures, we unnecessarily consider wf predicates for an RPIT if it is coming from a foreign crate.

Fixes #107036

r? `@oli-obk` but feel free to reassign

1 files changed, 1 insertions, 1 deletions

diff --git a/compiler/rustc_trait_selection/src/traits/wf.rs b/compiler/rustc_trait_selection/src/traits/wf.rs
index b47a70b4e7b..12d4cb4fc69 100644
--- a/compiler/rustc_trait_selection/src/traits/wf.rs
+++ b/compiler/rustc_trait_selection/src/traits/wf.rs
@@ -654,7 +654,7 @@ impl<'tcx> WfPredicates<'tcx> {
                     // All of the requirements on type parameters
                     // have already been checked for `impl Trait` in
                     // return position. We do need to check type-alias-impl-trait though.
-                    if ty::is_impl_trait_defn(self.tcx, def_id).is_none() {
+                    if self.tcx.is_type_alias_impl_trait(def_id) {
                         let obligations = self.nominal_obligations(def_id, substs);
                         self.out.extend(obligations);
                     }