diff options
Diffstat (limited to 'compiler/rustc_ty_utils/src/instance.rs')
| -rw-r--r-- | compiler/rustc_ty_utils/src/instance.rs | 91 |
1 files changed, 73 insertions, 18 deletions
diff --git a/compiler/rustc_ty_utils/src/instance.rs b/compiler/rustc_ty_utils/src/instance.rs index 64586a6782b..36a20c78fcc 100644 --- a/compiler/rustc_ty_utils/src/instance.rs +++ b/compiler/rustc_ty_utils/src/instance.rs @@ -1,6 +1,7 @@ use rustc_errors::ErrorGuaranteed; use rustc_hir::def_id::DefId; use rustc_infer::infer::TyCtxtInferExt; +use rustc_middle::query::Providers; use rustc_middle::traits::CodegenObligationError; use rustc_middle::ty::subst::SubstsRef; use rustc_middle::ty::{self, Instance, TyCtxt, TypeVisitableExt}; @@ -27,8 +28,7 @@ fn resolve_instance<'tcx>( ) } else { let ty = tcx.type_of(def); - let item_type = - tcx.subst_and_normalize_erasing_regions(substs, param_env, ty.skip_binder()); + let item_type = tcx.subst_and_normalize_erasing_regions(substs, param_env, ty); let def = match *item_type.kind() { ty::FnDef(def_id, ..) if tcx.is_intrinsic(def_id) => { @@ -85,7 +85,7 @@ fn resolve_associated_item<'tcx>( Err(CodegenObligationError::Ambiguity) => { let reported = tcx.sess.delay_span_bug( tcx.def_span(trait_item_id), - &format!( + format!( "encountered ambiguity selecting `{trait_ref:?}` during codegen, presuming due to \ overflow or prior type error", ), @@ -177,15 +177,52 @@ fn resolve_associated_item<'tcx>( Some(ty::Instance::new(leaf_def.item.def_id, substs)) } - traits::ImplSource::Generator(generator_data) => Some(Instance { - def: ty::InstanceDef::Item(generator_data.generator_def_id), - substs: generator_data.substs, - }), - traits::ImplSource::Future(future_data) => Some(Instance { - def: ty::InstanceDef::Item(future_data.generator_def_id), - substs: future_data.substs, - }), + traits::ImplSource::Generator(generator_data) => { + if cfg!(debug_assertions) && tcx.item_name(trait_item_id) != sym::resume { + // For compiler developers who'd like to add new items to `Generator`, + // you either need to generate a shim body, or perhaps return + // `InstanceDef::Item` pointing to a trait default method body if + // it is given a default implementation by the trait. + span_bug!( + tcx.def_span(generator_data.generator_def_id), + "no definition for `{trait_ref}::{}` for built-in generator type", + tcx.item_name(trait_item_id) + ) + } + Some(Instance { + def: ty::InstanceDef::Item(generator_data.generator_def_id), + substs: generator_data.substs, + }) + } + traits::ImplSource::Future(future_data) => { + if Some(trait_item_id) == tcx.lang_items().future_poll_fn() { + // `Future::poll` is generated by the compiler. + Some(Instance { + def: ty::InstanceDef::Item(future_data.generator_def_id), + substs: future_data.substs, + }) + } else { + // All other methods are default methods of the `Future` trait. + // (this assumes that `ImplSource::Future` is only used for methods on `Future`) + debug_assert!(tcx.impl_defaultness(trait_item_id).has_value()); + Some(Instance::new(trait_item_id, rcvr_substs)) + } + } traits::ImplSource::Closure(closure_data) => { + if cfg!(debug_assertions) + && ![sym::call, sym::call_mut, sym::call_once] + .contains(&tcx.item_name(trait_item_id)) + { + // For compiler developers who'd like to add new items to `Fn`/`FnMut`/`FnOnce`, + // you either need to generate a shim body, or perhaps return + // `InstanceDef::Item` pointing to a trait default method body if + // it is given a default implementation by the trait. + span_bug!( + tcx.def_span(closure_data.closure_def_id), + "no definition for `{trait_ref}::{}` for built-in closure type", + tcx.item_name(trait_item_id) + ) + } let trait_closure_kind = tcx.fn_trait_kind_from_def_id(trait_id).unwrap(); Instance::resolve_closure( tcx, @@ -195,11 +232,29 @@ fn resolve_associated_item<'tcx>( ) } traits::ImplSource::FnPointer(ref data) => match data.fn_ty.kind() { - ty::FnDef(..) | ty::FnPtr(..) => Some(Instance { - def: ty::InstanceDef::FnPtrShim(trait_item_id, data.fn_ty), - substs: rcvr_substs, - }), - _ => None, + ty::FnDef(..) | ty::FnPtr(..) => { + if cfg!(debug_assertions) + && ![sym::call, sym::call_mut, sym::call_once] + .contains(&tcx.item_name(trait_item_id)) + { + // For compiler developers who'd like to add new items to `Fn`/`FnMut`/`FnOnce`, + // you either need to generate a shim body, or perhaps return + // `InstanceDef::Item` pointing to a trait default method body if + // it is given a default implementation by the trait. + bug!( + "no definition for `{trait_ref}::{}` for built-in fn type", + tcx.item_name(trait_item_id) + ) + } + Some(Instance { + def: ty::InstanceDef::FnPtrShim(trait_item_id, data.fn_ty), + substs: rcvr_substs, + }) + } + _ => bug!( + "no built-in definition for `{trait_ref}::{}` for non-fn type", + tcx.item_name(trait_item_id) + ), }, traits::ImplSource::Object(ref data) => { traits::get_vtable_index_of_object_method(tcx, data, trait_item_id).map(|index| { @@ -265,6 +320,6 @@ fn resolve_associated_item<'tcx>( }) } -pub fn provide(providers: &mut ty::query::Providers) { - *providers = ty::query::Providers { resolve_instance, ..*providers }; +pub fn provide(providers: &mut Providers) { + *providers = Providers { resolve_instance, ..*providers }; } |