Meow copy query cycle

Author: compiler-errors

compiler/rustc_next_trait_solver/src/solve/trait_goals.rs

@@ -274,6 +274,22 @@ where
             return Err(NoSolution);
         }
 
+        // TODO:
+        if let ty::CoroutineWitness(def_id, _) = goal.predicate.self_ty().kind() {
+            match ecx.typing_mode() {
+                TypingMode::Analysis { stalled_generators, defining_opaque_types: _ } => {
+                    if def_id.as_local().is_some_and(|def_id| stalled_generators.contains(&def_id))
+                    {
+                        return ecx.forced_ambiguity(MaybeCause::Ambiguity);
+                    }
+                }
+                TypingMode::Coherence
+                | TypingMode::PostAnalysis
+                | TypingMode::Borrowck { defining_opaque_types: _ }
+                | TypingMode::PostBorrowckAnalysis { defined_opaque_types: _ } => {}
+            }
+        }
+
         ecx.probe_and_evaluate_goal_for_constituent_tys(
             CandidateSource::BuiltinImpl(BuiltinImplSource::Misc),
             goal,

compiler/rustc_trait_selection/src/infer.rs

@@ -34,7 +34,7 @@ impl<'tcx> InferCtxt<'tcx> {
 
         // FIXME(#132279): This should be removed as it causes us to incorrectly
         // handle opaques in their defining scope.
-        if !(param_env, ty).has_infer() {
+        if !self.next_trait_solver() && !(param_env, ty).has_infer() {
             return self.tcx.type_is_copy_modulo_regions(self.typing_env(param_env), ty);
         }