]> git.lizzy.rs Git - rust.git/blobdiff - compiler/rustc_hir_analysis/src/check/check.rs
Auto merge of #106938 - GuillaumeGomez:normalize-projection-field-ty, r=oli-obk
[rust.git] / compiler / rustc_hir_analysis / src / check / check.rs
index 248ff1d4cb50633e770f3c46cfc3cc42c5d77591..5e3601efbbe8edf9b44ab825001d51e4dc8c2cb1 100644 (file)
@@ -14,7 +14,7 @@
 use rustc_infer::infer::opaque_types::ConstrainOpaqueTypeRegionVisitor;
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{DefiningAnchor, RegionVariableOrigin, TyCtxtInferExt};
-use rustc_infer::traits::Obligation;
+use rustc_infer::traits::{Obligation, TraitEngineExt as _};
 use rustc_lint::builtin::REPR_TRANSPARENT_EXTERNAL_PRIVATE_FIELDS;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::middle::stability::EvalResult;
@@ -28,7 +28,7 @@
 use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::traits::error_reporting::on_unimplemented::OnUnimplementedDirective;
 use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
-use rustc_trait_selection::traits::{self, ObligationCtxt};
+use rustc_trait_selection::traits::{self, ObligationCtxt, TraitEngine, TraitEngineExt as _};
 
 use std::ops::ControlFlow;
 
@@ -267,7 +267,7 @@ impl<'tcx> ty::visit::TypeVisitor<'tcx> for ProhibitOpaqueVisitor<'tcx> {
         fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
             debug!(?t, "root_visit_ty");
             if t == self.opaque_identity_ty {
-                ControlFlow::CONTINUE
+                ControlFlow::Continue(())
             } else {
                 t.visit_with(&mut ConstrainOpaqueTypeRegionVisitor {
                     tcx: self.tcx,
@@ -282,7 +282,7 @@ fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
                 if self.references_parent_regions {
                     ControlFlow::Break(t)
                 } else {
-                    ControlFlow::CONTINUE
+                    ControlFlow::Continue(())
                 }
             }
         }
@@ -412,7 +412,6 @@ fn check_opaque_meets_bounds<'tcx>(
     span: Span,
     origin: &hir::OpaqueTyOrigin,
 ) {
-    let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
     let defining_use_anchor = match *origin {
         hir::OpaqueTyOrigin::FnReturn(did) | hir::OpaqueTyOrigin::AsyncFn(did) => did,
         hir::OpaqueTyOrigin::TyAlias => def_id,
@@ -438,11 +437,12 @@ fn check_opaque_meets_bounds<'tcx>(
         _ => re,
     });
 
-    let misc_cause = traits::ObligationCause::misc(span, hir_id);
+    let misc_cause = traits::ObligationCause::misc(span, def_id);
 
     match ocx.eq(&misc_cause, param_env, opaque_ty, hidden_ty) {
         Ok(()) => {}
         Err(ty_err) => {
+            let ty_err = ty_err.to_string(tcx);
             tcx.sess.delay_span_bug(
                 span,
                 &format!("could not unify `{hidden_ty}` with revealed type:\n{ty_err}"),
@@ -531,16 +531,14 @@ fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
         DefKind::Fn => {} // entirely within check_item_body
         DefKind::Impl => {
             let it = tcx.hir().item(id);
-            let hir::ItemKind::Impl(ref impl_) = it.kind else {
-                return;
-            };
+            let hir::ItemKind::Impl(impl_) = it.kind else { return };
             debug!("ItemKind::Impl {} with id {:?}", it.ident, it.owner_id);
             if let Some(impl_trait_ref) = tcx.impl_trait_ref(it.owner_id) {
                 check_impl_items_against_trait(
                     tcx,
                     it.span,
                     it.owner_id.def_id,
-                    impl_trait_ref,
+                    impl_trait_ref.subst_identity(),
                     &impl_.items,
                 );
                 check_on_unimplemented(tcx, it);
@@ -548,15 +546,15 @@ fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
         }
         DefKind::Trait => {
             let it = tcx.hir().item(id);
-            let hir::ItemKind::Trait(_, _, _, _, ref items) = it.kind else {
+            let hir::ItemKind::Trait(_, _, _, _, items) = it.kind else {
                 return;
             };
             check_on_unimplemented(tcx, it);
 
             for item in items.iter() {
                 let item = tcx.hir().trait_item(item.id);
-                match item.kind {
-                    hir::TraitItemKind::Fn(ref sig, _) => {
+                match &item.kind {
+                    hir::TraitItemKind::Fn(sig, _) => {
                         let abi = sig.header.abi;
                         fn_maybe_err(tcx, item.ident.span, abi);
                     }
@@ -608,59 +606,66 @@ fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
             };
             check_abi(tcx, it.hir_id(), it.span, abi);
 
-            if abi == Abi::RustIntrinsic {
-                for item in items {
-                    let item = tcx.hir().foreign_item(item.id);
-                    intrinsic::check_intrinsic_type(tcx, item);
-                }
-            } else if abi == Abi::PlatformIntrinsic {
-                for item in items {
-                    let item = tcx.hir().foreign_item(item.id);
-                    intrinsic::check_platform_intrinsic_type(tcx, item);
+            match abi {
+                Abi::RustIntrinsic => {
+                    for item in items {
+                        let item = tcx.hir().foreign_item(item.id);
+                        intrinsic::check_intrinsic_type(tcx, item);
+                    }
                 }
-            } else {
-                for item in items {
-                    let def_id = item.id.owner_id.def_id;
-                    let generics = tcx.generics_of(def_id);
-                    let own_counts = generics.own_counts();
-                    if generics.params.len() - own_counts.lifetimes != 0 {
-                        let (kinds, kinds_pl, egs) = match (own_counts.types, own_counts.consts) {
-                            (_, 0) => ("type", "types", Some("u32")),
-                            // We don't specify an example value, because we can't generate
-                            // a valid value for any type.
-                            (0, _) => ("const", "consts", None),
-                            _ => ("type or const", "types or consts", None),
-                        };
-                        struct_span_err!(
-                            tcx.sess,
-                            item.span,
-                            E0044,
-                            "foreign items may not have {kinds} parameters",
-                        )
-                        .span_label(item.span, &format!("can't have {kinds} parameters"))
-                        .help(
-                            // FIXME: once we start storing spans for type arguments, turn this
-                            // into a suggestion.
-                            &format!(
-                                "replace the {} parameters with concrete {}{}",
-                                kinds,
-                                kinds_pl,
-                                egs.map(|egs| format!(" like `{}`", egs)).unwrap_or_default(),
-                            ),
-                        )
-                        .emit();
+
+                Abi::PlatformIntrinsic => {
+                    for item in items {
+                        let item = tcx.hir().foreign_item(item.id);
+                        intrinsic::check_platform_intrinsic_type(tcx, item);
                     }
+                }
 
-                    let item = tcx.hir().foreign_item(item.id);
-                    match item.kind {
-                        hir::ForeignItemKind::Fn(ref fn_decl, _, _) => {
-                            require_c_abi_if_c_variadic(tcx, fn_decl, abi, item.span);
+                _ => {
+                    for item in items {
+                        let def_id = item.id.owner_id.def_id;
+                        let generics = tcx.generics_of(def_id);
+                        let own_counts = generics.own_counts();
+                        if generics.params.len() - own_counts.lifetimes != 0 {
+                            let (kinds, kinds_pl, egs) = match (own_counts.types, own_counts.consts)
+                            {
+                                (_, 0) => ("type", "types", Some("u32")),
+                                // We don't specify an example value, because we can't generate
+                                // a valid value for any type.
+                                (0, _) => ("const", "consts", None),
+                                _ => ("type or const", "types or consts", None),
+                            };
+                            struct_span_err!(
+                                tcx.sess,
+                                item.span,
+                                E0044,
+                                "foreign items may not have {kinds} parameters",
+                            )
+                            .span_label(item.span, &format!("can't have {kinds} parameters"))
+                            .help(
+                                // FIXME: once we start storing spans for type arguments, turn this
+                                // into a suggestion.
+                                &format!(
+                                    "replace the {} parameters with concrete {}{}",
+                                    kinds,
+                                    kinds_pl,
+                                    egs.map(|egs| format!(" like `{}`", egs)).unwrap_or_default(),
+                                ),
+                            )
+                            .emit();
                         }
-                        hir::ForeignItemKind::Static(..) => {
-                            check_static_inhabited(tcx, def_id);
-                            check_static_linkage(tcx, def_id);
+
+                        let item = tcx.hir().foreign_item(item.id);
+                        match &item.kind {
+                            hir::ForeignItemKind::Fn(fn_decl, _, _) => {
+                                require_c_abi_if_c_variadic(tcx, fn_decl, abi, item.span);
+                            }
+                            hir::ForeignItemKind::Static(..) => {
+                                check_static_inhabited(tcx, def_id);
+                                check_static_linkage(tcx, def_id);
+                            }
+                            _ => {}
                         }
-                        _ => {}
                     }
                 }
             }
@@ -668,7 +673,7 @@ fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
         DefKind::GlobalAsm => {
             let it = tcx.hir().item(id);
             let hir::ItemKind::GlobalAsm(asm) = it.kind else { span_bug!(it.span, "DefKind::GlobalAsm but got {:#?}", it) };
-            InlineAsmCtxt::new_global_asm(tcx).check_asm(asm, id.hir_id());
+            InlineAsmCtxt::new_global_asm(tcx).check_asm(asm, id.owner_id.def_id);
         }
         _ => {}
     }
@@ -1393,11 +1398,15 @@ fn async_opaque_type_cycle_error(tcx: TyCtxt<'_>, span: Span) -> ErrorGuaranteed
 ///
 /// If all the return expressions evaluate to `!`, then we explain that the error will go away
 /// after changing it. This can happen when a user uses `panic!()` or similar as a placeholder.
-fn opaque_type_cycle_error(tcx: TyCtxt<'_>, def_id: LocalDefId, span: Span) -> ErrorGuaranteed {
+fn opaque_type_cycle_error(
+    tcx: TyCtxt<'_>,
+    opaque_def_id: LocalDefId,
+    span: Span,
+) -> ErrorGuaranteed {
     let mut err = struct_span_err!(tcx.sess, span, E0720, "cannot resolve opaque type");
 
     let mut label = false;
-    if let Some((def_id, visitor)) = get_owner_return_paths(tcx, def_id) {
+    if let Some((def_id, visitor)) = get_owner_return_paths(tcx, opaque_def_id) {
         let typeck_results = tcx.typeck(def_id);
         if visitor
             .returns
@@ -1433,28 +1442,72 @@ fn opaque_type_cycle_error(tcx: TyCtxt<'_>, def_id: LocalDefId, span: Span) -> E
                 .filter_map(|e| typeck_results.node_type_opt(e.hir_id).map(|t| (e.span, t)))
                 .filter(|(_, ty)| !matches!(ty.kind(), ty::Never))
             {
-                struct OpaqueTypeCollector(Vec<DefId>);
+                #[derive(Default)]
+                struct OpaqueTypeCollector {
+                    opaques: Vec<DefId>,
+                    closures: Vec<DefId>,
+                }
                 impl<'tcx> ty::visit::TypeVisitor<'tcx> for OpaqueTypeCollector {
                     fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
                         match *t.kind() {
                             ty::Alias(ty::Opaque, ty::AliasTy { def_id: def, .. }) => {
-                                self.0.push(def);
-                                ControlFlow::CONTINUE
+                                self.opaques.push(def);
+                                ControlFlow::Continue(())
+                            }
+                            ty::Closure(def_id, ..) | ty::Generator(def_id, ..) => {
+                                self.closures.push(def_id);
+                                t.super_visit_with(self)
                             }
                             _ => t.super_visit_with(self),
                         }
                     }
                 }
-                let mut visitor = OpaqueTypeCollector(vec![]);
+
+                let mut visitor = OpaqueTypeCollector::default();
                 ty.visit_with(&mut visitor);
-                for def_id in visitor.0 {
+                for def_id in visitor.opaques {
                     let ty_span = tcx.def_span(def_id);
                     if !seen.contains(&ty_span) {
-                        err.span_label(ty_span, &format!("returning this opaque type `{ty}`"));
+                        let descr = if ty.is_impl_trait() { "opaque " } else { "" };
+                        err.span_label(ty_span, &format!("returning this {descr}type `{ty}`"));
                         seen.insert(ty_span);
                     }
                     err.span_label(sp, &format!("returning here with type `{ty}`"));
                 }
+
+                for closure_def_id in visitor.closures {
+                    let Some(closure_local_did) = closure_def_id.as_local() else { continue; };
+                    let typeck_results = tcx.typeck(closure_local_did);
+
+                    let mut label_match = |ty: Ty<'_>, span| {
+                        for arg in ty.walk() {
+                            if let ty::GenericArgKind::Type(ty) = arg.unpack()
+                                && let ty::Alias(ty::Opaque, ty::AliasTy { def_id: captured_def_id, .. }) = *ty.kind()
+                                && captured_def_id == opaque_def_id.to_def_id()
+                            {
+                                err.span_label(
+                                    span,
+                                    format!(
+                                        "{} captures itself here",
+                                        tcx.def_kind(closure_def_id).descr(closure_def_id)
+                                    ),
+                                );
+                            }
+                        }
+                    };
+
+                    // Label any closure upvars that capture the opaque
+                    for capture in typeck_results.closure_min_captures_flattened(closure_local_did)
+                    {
+                        label_match(capture.place.ty(), capture.get_path_span(tcx));
+                    }
+                    // Label any generator locals that capture the opaque
+                    for interior_ty in
+                        typeck_results.generator_interior_types.as_ref().skip_binder()
+                    {
+                        label_match(interior_ty.ty, interior_ty.span);
+                    }
+                }
             }
         }
     }
@@ -1463,3 +1516,34 @@ fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
     }
     err.emit()
 }
+
+pub(super) fn check_generator_obligations(tcx: TyCtxt<'_>, def_id: LocalDefId) {
+    debug_assert!(tcx.sess.opts.unstable_opts.drop_tracking_mir);
+    debug_assert!(matches!(tcx.def_kind(def_id), DefKind::Generator));
+
+    let typeck = tcx.typeck(def_id);
+    let param_env = tcx.param_env(def_id);
+
+    let generator_interior_predicates = &typeck.generator_interior_predicates[&def_id];
+    debug!(?generator_interior_predicates);
+
+    let infcx = tcx
+        .infer_ctxt()
+        // typeck writeback gives us predicates with their regions erased.
+        // As borrowck already has checked lifetimes, we do not need to do it again.
+        .ignoring_regions()
+        // Bind opaque types to `def_id` as they should have been checked by borrowck.
+        .with_opaque_type_inference(DefiningAnchor::Bind(def_id))
+        .build();
+
+    let mut fulfillment_cx = <dyn TraitEngine<'_>>::new(infcx.tcx);
+    for (predicate, cause) in generator_interior_predicates {
+        let obligation = Obligation::new(tcx, cause.clone(), param_env, *predicate);
+        fulfillment_cx.register_predicate_obligation(&infcx, obligation);
+    }
+    let errors = fulfillment_cx.select_all_or_error(&infcx);
+    debug!(?errors);
+    if !errors.is_empty() {
+        infcx.err_ctxt().report_fulfillment_errors(&errors, None);
+    }
+}