diff --git a/compiler/rustc_trait_selection/src/solve/opaques.rs b/compiler/rustc_trait_selection/src/solve/opaques.rs index 54557aeb9a2dd..a5de4ddee82ba 100644 --- a/compiler/rustc_trait_selection/src/solve/opaques.rs +++ b/compiler/rustc_trait_selection/src/solve/opaques.rs @@ -15,51 +15,48 @@ impl<'tcx> EvalCtxt<'_, 'tcx> { let opaque_ty = goal.predicate.projection_ty; let expected = goal.predicate.term.ty().expect("no such thing as an opaque const"); - match goal.param_env.reveal() { - Reveal::UserFacing => match self.solver_mode() { - SolverMode::Normal => { - let Some(opaque_ty_def_id) = opaque_ty.def_id.as_local() else { - return Err(NoSolution); - }; - let opaque_ty = - ty::OpaqueTypeKey { def_id: opaque_ty_def_id, substs: opaque_ty.substs }; - // FIXME: at some point we should call queries without defining - // new opaque types but having the existing opaque type definitions. - // This will require moving this below "Prefer opaques registered already". - if !self.can_define_opaque_ty(opaque_ty_def_id) { - return Err(NoSolution); - } - // FIXME: This may have issues when the substs contain aliases... - match self.tcx().uses_unique_placeholders_ignoring_regions(opaque_ty.substs) { - Err(NotUniqueParam::NotParam(param)) if param.is_non_region_infer() => { - return self.evaluate_added_goals_and_make_canonical_response( - Certainty::AMBIGUOUS, - ); - } - Err(_) => { - return Err(NoSolution); - } - Ok(()) => {} + match (goal.param_env.reveal(), self.solver_mode()) { + (Reveal::UserFacing, SolverMode::Normal) => { + let Some(opaque_ty_def_id) = opaque_ty.def_id.as_local() else { + return Err(NoSolution); + }; + let opaque_ty = + ty::OpaqueTypeKey { def_id: opaque_ty_def_id, substs: opaque_ty.substs }; + // FIXME: at some point we should call queries without defining + // new opaque types but having the existing opaque type definitions. + // This will require moving this below "Prefer opaques registered already". + if !self.can_define_opaque_ty(opaque_ty_def_id) { + return Err(NoSolution); + } + // FIXME: This may have issues when the substs contain aliases... + match self.tcx().uses_unique_placeholders_ignoring_regions(opaque_ty.substs) { + Err(NotUniqueParam::NotParam(param)) if param.is_non_region_infer() => { + return self.evaluate_added_goals_and_make_canonical_response( + Certainty::AMBIGUOUS, + ); } - // Prefer opaques registered already. - let matches = - self.unify_existing_opaque_tys(goal.param_env, opaque_ty, expected); - if !matches.is_empty() { - if let Some(response) = self.try_merge_responses(&matches) { - return Ok(response); - } else { - return self.flounder(&matches); - } + Err(_) => { + return Err(NoSolution); } - // Otherwise, define a new opaque type - self.register_opaque_ty(opaque_ty, expected, goal.param_env)?; - self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes) + Ok(()) => {} } - SolverMode::Coherence => { - self.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS) + // Prefer opaques registered already. + let matches = self.unify_existing_opaque_tys(goal.param_env, opaque_ty, expected); + if !matches.is_empty() { + if let Some(response) = self.try_merge_responses(&matches) { + return Ok(response); + } else { + return self.flounder(&matches); + } } - }, - Reveal::All => { + // Otherwise, define a new opaque type + self.register_opaque_ty(opaque_ty, expected, goal.param_env)?; + self.evaluate_added_goals_and_make_canonical_response(Certainty::Yes) + } + (Reveal::UserFacing, SolverMode::Coherence) => { + self.evaluate_added_goals_and_make_canonical_response(Certainty::AMBIGUOUS) + } + (Reveal::All, _) => { // FIXME: Add an assertion that opaque type storage is empty. let actual = tcx.type_of(opaque_ty.def_id).subst(tcx, opaque_ty.substs); self.eq(goal.param_env, expected, actual)?;