diff options
Diffstat (limited to 'compiler/rustc_hir_analysis')
6 files changed, 64 insertions, 21 deletions
diff --git a/compiler/rustc_hir_analysis/src/check/wfcheck.rs b/compiler/rustc_hir_analysis/src/check/wfcheck.rs index e6ea6eddcaa..d72cf00293f 100644 --- a/compiler/rustc_hir_analysis/src/check/wfcheck.rs +++ b/compiler/rustc_hir_analysis/src/check/wfcheck.rs @@ -966,7 +966,7 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) -> Result<(), let ty = tcx.type_of(param.def_id).instantiate_identity(); if tcx.features().unsized_const_params() { - enter_wf_checking_ctxt(tcx, hir_ty.span, param.def_id, |wfcx| { + enter_wf_checking_ctxt(tcx, hir_ty.span, tcx.local_parent(param.def_id), |wfcx| { wfcx.register_bound( ObligationCause::new( hir_ty.span, @@ -980,7 +980,7 @@ fn check_param_wf(tcx: TyCtxt<'_>, param: &hir::GenericParam<'_>) -> Result<(), Ok(()) }) } else if tcx.features().adt_const_params() { - enter_wf_checking_ctxt(tcx, hir_ty.span, param.def_id, |wfcx| { + enter_wf_checking_ctxt(tcx, hir_ty.span, tcx.local_parent(param.def_id), |wfcx| { wfcx.register_bound( ObligationCause::new( hir_ty.span, diff --git a/compiler/rustc_hir_analysis/src/collect.rs b/compiler/rustc_hir_analysis/src/collect.rs index 08d63f4349e..027aa5554a4 100644 --- a/compiler/rustc_hir_analysis/src/collect.rs +++ b/compiler/rustc_hir_analysis/src/collect.rs @@ -1822,6 +1822,9 @@ fn const_param_default<'tcx>( ), }; let icx = ItemCtxt::new(tcx, def_id); - let ct = icx.lowerer().lower_const_arg(default_ct, FeedConstTy::Param(def_id.to_def_id())); + let identity_args = ty::GenericArgs::identity_for_item(tcx, def_id); + let ct = icx + .lowerer() + .lower_const_arg(default_ct, FeedConstTy::Param(def_id.to_def_id(), identity_args)); ty::EarlyBinder::bind(ct) } diff --git a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs index 5b511d27074..49549335363 100644 --- a/compiler/rustc_hir_analysis/src/collect/predicates_of.rs +++ b/compiler/rustc_hir_analysis/src/collect/predicates_of.rs @@ -223,10 +223,7 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: LocalDefId) -> ty::Gen } hir::GenericParamKind::Const { .. } => { let param_def_id = param.def_id.to_def_id(); - let ct_ty = tcx - .type_of(param_def_id) - .no_bound_vars() - .expect("const parameters cannot be generic"); + let ct_ty = tcx.type_of(param_def_id).instantiate_identity(); let ct = icx.lowerer().lower_const_param(param_def_id, param.hir_id); predicates .insert((ty::ClauseKind::ConstArgHasType(ct, ct_ty).upcast(tcx), param.span)); diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs index 8d58a3bfbd3..fa58f12c553 100644 --- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs +++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/generics.rs @@ -273,7 +273,7 @@ pub fn lower_generic_args<'tcx: 'a, 'a>( // We lower to an infer even when the feature gate is not enabled // as it is useful for diagnostics to be able to see a `ConstKind::Infer` - args.push(ctx.provided_kind(param, arg)); + args.push(ctx.provided_kind(&args, param, arg)); args_iter.next(); params.next(); } diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs index 750770178ee..a0f848f07c4 100644 --- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs +++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs @@ -232,12 +232,15 @@ impl AssocItemQSelf { /// Use this enum with `<dyn HirTyLowerer>::lower_const_arg` to instruct it with the /// desired behavior. #[derive(Debug, Clone, Copy)] -pub enum FeedConstTy { +pub enum FeedConstTy<'a, 'tcx> { /// Feed the type. /// /// The `DefId` belongs to the const param that we are supplying /// this (anon) const arg to. - Param(DefId), + /// + /// The list of generic args is used to instantiate the parameters + /// used by the type of the const param specified by `DefId`. + Param(DefId, &'a [ty::GenericArg<'tcx>]), /// Don't feed the type. No, } @@ -298,6 +301,7 @@ pub trait GenericArgsLowerer<'a, 'tcx> { fn provided_kind( &mut self, + preceding_args: &[ty::GenericArg<'tcx>], param: &ty::GenericParamDef, arg: &GenericArg<'tcx>, ) -> ty::GenericArg<'tcx>; @@ -481,6 +485,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { fn provided_kind( &mut self, + preceding_args: &[ty::GenericArg<'tcx>], param: &ty::GenericParamDef, arg: &GenericArg<'tcx>, ) -> ty::GenericArg<'tcx> { @@ -526,7 +531,10 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { (GenericParamDefKind::Const { .. }, GenericArg::Const(ct)) => self .lowerer // Ambig portions of `ConstArg` are handled in the match arm below - .lower_const_arg(ct.as_unambig_ct(), FeedConstTy::Param(param.def_id)) + .lower_const_arg( + ct.as_unambig_ct(), + FeedConstTy::Param(param.def_id, preceding_args), + ) .into(), (&GenericParamDefKind::Const { .. }, GenericArg::Infer(inf)) => { self.lowerer.ct_infer(Some(param), inf.span).into() @@ -582,8 +590,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { let ty = tcx .at(self.span) .type_of(param.def_id) - .no_bound_vars() - .expect("const parameter types cannot be generic"); + .instantiate(tcx, preceding_args); if let Err(guar) = ty.error_reported() { return ty::Const::new_error(tcx, guar).into(); } @@ -2107,14 +2114,50 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { pub fn lower_const_arg( &self, const_arg: &hir::ConstArg<'tcx>, - feed: FeedConstTy, + feed: FeedConstTy<'_, 'tcx>, ) -> Const<'tcx> { let tcx = self.tcx(); - if let FeedConstTy::Param(param_def_id) = feed + if let FeedConstTy::Param(param_def_id, args) = feed && let hir::ConstArgKind::Anon(anon) = &const_arg.kind { - tcx.feed_anon_const_type(anon.def_id, tcx.type_of(param_def_id)); + let anon_const_type = tcx.type_of(param_def_id).instantiate(tcx, args); + + // We must error if the instantiated type has any inference variables as we will + // use this type to feed the `type_of` and query results must not contain inference + // variables otherwise we will ICE. + // + // We also error if the type contains any regions as effectively any region will wind + // up as a region variable in mir borrowck. It would also be somewhat concerning if + // hir typeck was using equality but mir borrowck wound up using subtyping as that could + // result in a non-infer in hir typeck but a region variable in borrowck. + // + // FIXME(generic_const_parameter_types): Ideally we remove these errors one day when + // we have the ability to intermix typeck of anon const const args with the parent + // bodies typeck. + if tcx.features().generic_const_parameter_types() + && (anon_const_type.has_free_regions() || anon_const_type.has_erased_regions()) + { + let e = tcx.dcx().span_err( + const_arg.span(), + "anonymous constants with lifetimes in their type are not yet supported", + ); + tcx.feed_anon_const_type(anon.def_id, ty::EarlyBinder::bind(Ty::new_error(tcx, e))); + return ty::Const::new_error(tcx, e); + } + if anon_const_type.has_non_region_infer() { + let e = tcx.dcx().span_err( + const_arg.span(), + "anonymous constants with inferred types are not yet supported", + ); + tcx.feed_anon_const_type(anon.def_id, ty::EarlyBinder::bind(Ty::new_error(tcx, e))); + return ty::Const::new_error(tcx, e); + } + + tcx.feed_anon_const_type( + anon.def_id, + ty::EarlyBinder::bind(tcx.type_of(param_def_id).instantiate(tcx, args)), + ); } let hir_id = const_arg.hir_id; @@ -2230,10 +2273,10 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ { let expr = &tcx.hir_body(anon.body).value; debug!(?expr); - let ty = tcx - .type_of(anon.def_id) - .no_bound_vars() - .expect("const parameter types cannot be generic"); + // FIXME(generic_const_parameter_types): We should use the proper generic args + // here. It's only used as a hint for literals so doesn't matter too much to use the right + // generic arguments, just weaker type inference. + let ty = tcx.type_of(anon.def_id).instantiate_identity(); match self.try_lower_anon_const_lit(ty, expr) { Some(v) => v, diff --git a/compiler/rustc_hir_analysis/src/lib.rs b/compiler/rustc_hir_analysis/src/lib.rs index bdfbd540e40..cf18bab950a 100644 --- a/compiler/rustc_hir_analysis/src/lib.rs +++ b/compiler/rustc_hir_analysis/src/lib.rs @@ -260,7 +260,7 @@ pub fn lower_ty<'tcx>(tcx: TyCtxt<'tcx>, hir_ty: &hir::Ty<'tcx>) -> Ty<'tcx> { pub fn lower_const_arg_for_rustdoc<'tcx>( tcx: TyCtxt<'tcx>, hir_ct: &hir::ConstArg<'tcx>, - feed: FeedConstTy, + feed: FeedConstTy<'_, 'tcx>, ) -> Const<'tcx> { let env_def_id = tcx.hir_get_parent_item(hir_ct.hir_id); collect::ItemCtxt::new(tcx, env_def_id.def_id).lowerer().lower_const_arg(hir_ct, feed) |