Auto merge of #117213 - oli-obk:check_item_type_cleanup, r=<try>

 Reorder check_item_type diagnostics so they occur next to the corresponding `check_well_formed` diagnostics

The first commit is just a cleanup.

The second commit moves most checks from `check_mod_item_types` into `check_well_formed`, invoking the checks in lockstep per-item instead of iterating over all items twice.

compiler/rustc_hir_analysis/src/check/check.rs

@@ -8,7 +8,7 @@ use rustc_attr as attr;
 use rustc_errors::{ErrorGuaranteed, MultiSpan};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind};
-use rustc_hir::def_id::{DefId, LocalDefId, LocalModDefId};
+use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::Node;
 use rustc_infer::infer::outlives::env::OutlivesEnvironment;
 use rustc_infer::infer::{RegionVariableOrigin, TyCtxtInferExt};
@@ -201,8 +201,8 @@ fn check_static_inhabited(tcx: TyCtxt<'_>, def_id: LocalDefId) {
 
 /// Checks that an opaque type does not contain cycles and does not use `Self` or `T::Foo`
 /// projections that would result in "inheriting lifetimes".
-fn check_opaque(tcx: TyCtxt<'_>, id: hir::ItemId) {
-    let item = tcx.hir().item(id);
+fn check_opaque(tcx: TyCtxt<'_>, def_id: LocalDefId) {
+    let item = tcx.hir().expect_item(def_id);
     let hir::ItemKind::OpaqueTy(hir::OpaqueTy { origin, .. }) = item.kind else {
         tcx.sess.delay_span_bug(item.span, "expected opaque item");
         return;
@@ -443,40 +443,35 @@ fn check_static_linkage(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     }
 }
 
-fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
-    debug!(
-        "check_item_type(it.def_id={:?}, it.name={})",
-        id.owner_id,
-        tcx.def_path_str(id.owner_id)
-    );
+pub(crate) fn check_item_type(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     let _indenter = indenter();
-    match tcx.def_kind(id.owner_id) {
+    match tcx.def_kind(def_id) {
         DefKind::Static(..) => {
-            tcx.ensure().typeck(id.owner_id.def_id);
-            maybe_check_static_with_link_section(tcx, id.owner_id.def_id);
-            check_static_inhabited(tcx, id.owner_id.def_id);
-            check_static_linkage(tcx, id.owner_id.def_id);
+            tcx.ensure().typeck(def_id);
+            maybe_check_static_with_link_section(tcx, def_id);
+            check_static_inhabited(tcx, def_id);
+            check_static_linkage(tcx, def_id);
         }
         DefKind::Const => {
-            tcx.ensure().typeck(id.owner_id.def_id);
+            tcx.ensure().typeck(def_id);
         }
         DefKind::Enum => {
-            check_enum(tcx, id.owner_id.def_id);
+            check_enum(tcx, def_id);
         }
         DefKind::Fn => {} // entirely within check_item_body
         DefKind::Impl { of_trait } => {
-            if of_trait && let Some(impl_trait_ref) = tcx.impl_trait_ref(id.owner_id) {
+            if of_trait && let Some(impl_trait_ref) = tcx.impl_trait_ref(def_id) {
                 check_impl_items_against_trait(
                     tcx,
-                    id.owner_id.def_id,
+                    def_id,
                     impl_trait_ref.instantiate_identity(),
                 );
-                check_on_unimplemented(tcx, id);
+                check_on_unimplemented(tcx, def_id);
             }
         }
         DefKind::Trait => {
-            let assoc_items = tcx.associated_items(id.owner_id);
-            check_on_unimplemented(tcx, id);
+            let assoc_items = tcx.associated_items(def_id);
+            check_on_unimplemented(tcx, def_id);
 
             for &assoc_item in assoc_items.in_definition_order() {
                 match assoc_item.kind {
@@ -485,43 +480,43 @@ fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
                         fn_maybe_err(tcx, assoc_item.ident(tcx).span, abi);
                     }
                     ty::AssocKind::Type if assoc_item.defaultness(tcx).has_value() => {
-                        let trait_args = GenericArgs::identity_for_item(tcx, id.owner_id);
+                        let trait_args = GenericArgs::identity_for_item(tcx, def_id);
                         let _: Result<_, rustc_errors::ErrorGuaranteed> = check_type_bounds(
                             tcx,
                             assoc_item,
                             assoc_item,
-                            ty::TraitRef::new(tcx, id.owner_id.to_def_id(), trait_args),
+                            ty::TraitRef::new(tcx, def_id.to_def_id(), trait_args),
                         );
                     }
                     _ => {}
                 }
             }
         }
         DefKind::Struct => {
-            check_struct(tcx, id.owner_id.def_id);
+            check_struct(tcx, def_id);
         }
         DefKind::Union => {
-            check_union(tcx, id.owner_id.def_id);
+            check_union(tcx, def_id);
         }
         DefKind::OpaqueTy => {
-            let origin = tcx.opaque_type_origin(id.owner_id.def_id);
+            let origin = tcx.opaque_type_origin(def_id);
             if let hir::OpaqueTyOrigin::FnReturn(fn_def_id)
             | hir::OpaqueTyOrigin::AsyncFn(fn_def_id) = origin
                 && let hir::Node::TraitItem(trait_item) = tcx.hir().get_by_def_id(fn_def_id)
                 && let (_, hir::TraitFn::Required(..)) = trait_item.expect_fn()
             {
                 // Skip opaques from RPIT in traits with no default body.
             } else {
-                check_opaque(tcx, id);
+                check_opaque(tcx, def_id);
             }
         }
         DefKind::TyAlias => {
-            let pty_ty = tcx.type_of(id.owner_id).instantiate_identity();
-            let generics = tcx.generics_of(id.owner_id);
+            let pty_ty = tcx.type_of(def_id).instantiate_identity();
+            let generics = tcx.generics_of(def_id);
             check_type_params_are_used(tcx, &generics, pty_ty);
         }
         DefKind::ForeignMod => {
-            let it = tcx.hir().item(id);
+            let it = tcx.hir().expect_item(def_id);
             let hir::ItemKind::ForeignMod { abi, items } = it.kind else {
                 return;
             };
@@ -592,19 +587,19 @@ fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
             }
         }
         DefKind::GlobalAsm => {
-            let it = tcx.hir().item(id);
+            let it = tcx.hir().expect_item(def_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.owner_id.def_id);
+            InlineAsmCtxt::new_global_asm(tcx).check_asm(asm, def_id);
         }
         _ => {}
     }
 }
 
-pub(super) fn check_on_unimplemented(tcx: TyCtxt<'_>, item: hir::ItemId) {
+pub(super) fn check_on_unimplemented(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     // an error would be reported if this fails.
-    let _ = OnUnimplementedDirective::of_item(tcx, item.owner_id.to_def_id());
+    let _ = OnUnimplementedDirective::of_item(tcx, def_id.to_def_id());
 }
 
 pub(super) fn check_specialization_validity<'tcx>(
@@ -1314,16 +1309,6 @@ pub(super) fn check_type_params_are_used<'tcx>(
     }
 }
 
-pub(super) fn check_mod_item_types(tcx: TyCtxt<'_>, module_def_id: LocalModDefId) {
-    let module = tcx.hir_module_items(module_def_id);
-    for id in module.items() {
-        check_item_type(tcx, id);
-    }
-    if module_def_id == LocalModDefId::CRATE_DEF_ID {
-        super::entry::check_for_entry_fn(tcx);
-    }
-}
-
 fn async_opaque_type_cycle_error(tcx: TyCtxt<'_>, span: Span) -> ErrorGuaranteed {
     struct_span_err!(tcx.sess, span, E0733, "recursion in an `async fn` requires boxing")
         .span_label(span, "recursive `async fn`")

compiler/rustc_hir_analysis/src/check/entry.rs

@@ -14,7 +14,7 @@ use std::ops::Not;
 use super::check_function_signature;
 use crate::errors;
 
-pub(crate) fn check_for_entry_fn(tcx: TyCtxt<'_>) {
+pub(crate) fn check_for_entry_fn(tcx: TyCtxt<'_>, (): ()) {
     match tcx.entry_fn(()) {
         Some((def_id, EntryFnType::Main { .. })) => check_main_fn_ty(tcx, def_id),
         Some((def_id, EntryFnType::Start)) => check_start_fn_ty(tcx, def_id),

compiler/rustc_hir_analysis/src/check/mod.rs

@@ -75,7 +75,7 @@ pub use check::check_abi;
 
 use std::num::NonZeroU32;
 
-use check::check_mod_item_types;
+use entry::check_for_entry_fn;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::{pluralize, struct_span_err, Diagnostic, DiagnosticBuilder};
 use rustc_hir::def_id::{DefId, LocalDefId};
@@ -110,7 +110,7 @@ pub fn provide(providers: &mut Providers) {
     wfcheck::provide(providers);
     *providers = Providers {
         adt_destructor,
-        check_mod_item_types,
+        check_for_entry_fn,
         region_scope_tree,
         collect_return_position_impl_trait_in_trait_tys,
         compare_impl_const: compare_impl_item::compare_impl_const_raw,

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -171,7 +171,7 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) -> Result<()
         item.name = ? tcx.def_path_str(def_id)
     );
 
-    match item.kind {
+    let res = match item.kind {
         // Right now we check that every default trait implementation
         // has an implementation of itself. Basically, a case like:
         //
@@ -268,7 +268,11 @@ fn check_item<'tcx>(tcx: TyCtxt<'tcx>, item: &'tcx hir::Item<'tcx>) -> Result<()
             }
         }
         _ => Ok(()),
-    }
+    };
+
+    crate::check::check::check_item_type(tcx, def_id);
+
+    res
 }
 
 fn check_foreign_item(tcx: TyCtxt<'_>, item: &hir::ForeignItem<'_>) -> Result<(), ErrorGuaranteed> {

compiler/rustc_hir_analysis/src/lib.rs

@@ -206,13 +206,9 @@ pub fn check_crate(tcx: TyCtxt<'_>) -> Result<(), ErrorGuaranteed> {
         tcx.hir().try_par_for_each_module(|module| tcx.ensure().check_mod_type_wf(module))
     });
 
-    // NOTE: This is copy/pasted in librustdoc/core.rs and should be kept in sync.
-    tcx.sess.time("item_types_checking", || {
-        tcx.hir().for_each_module(|module| tcx.ensure().check_mod_item_types(module))
-    });
+    tcx.sess.time("entry_fn_checks", || tcx.ensure().check_for_entry_fn(()));
 
-    // HACK: `check_mod_type_wf` may spuriously emit errors due to `delay_span_bug`, even if those errors
-    // only actually get emitted in `check_mod_item_types`.
+    // HACK: `check_for_entry_fn` wants to report its errors even if `check_mod_type_wf` has errored.
     errs?;
 
     if tcx.features().rustc_attrs {

compiler/rustc_middle/src/query/mod.rs

@@ -935,8 +935,8 @@ rustc_queries! {
         desc { |tcx| "checking naked functions in {}", describe_as_module(key, tcx) }
     }
 
-    query check_mod_item_types(key: LocalModDefId) -> () {
-        desc { |tcx| "checking item types in {}", describe_as_module(key, tcx) }
+    query check_for_entry_fn(key: ()) -> () {
+        desc { |_tcx| "checking entry functions" }
     }
 
     query check_mod_privacy(key: LocalModDefId) -> () {

library/core/src/primitive_docs.rs

@@ -1077,26 +1077,6 @@ mod prim_tuple {}
 #[doc(hidden)]
 impl<T> (T,) {}
 
-// Fake impl that's only really used for docs.
-#[cfg(doc)]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(fake_variadic)]
-/// This trait is implemented on arbitrary-length tuples.
-impl<T: Clone> Clone for (T,) {
-    fn clone(&self) -> Self {
-        loop {}
-    }
-}
-
-// Fake impl that's only really used for docs.
-#[cfg(doc)]
-#[stable(feature = "rust1", since = "1.0.0")]
-#[doc(fake_variadic)]
-/// This trait is implemented on arbitrary-length tuples.
-impl<T: Copy> Copy for (T,) {
-    // empty
-}
-
 #[rustc_doc_primitive = "f32"]
 /// A 32-bit floating point type (specifically, the "binary32" type defined in IEEE 754-2008).
 ///

src/librustdoc/core.rs

@@ -320,9 +320,10 @@ pub(crate) fn run_global_ctxt(
         tcx.hir().for_each_module(|module| tcx.ensure().collect_mod_item_types(module))
     });
 
-    // NOTE: This is copy/pasted from typeck/lib.rs and should be kept in sync with those changes.
     tcx.sess.time("item_types_checking", || {
-        tcx.hir().for_each_module(|module| tcx.ensure().check_mod_item_types(module))
+        tcx.hir().for_each_module(|module| {
+            let _ = tcx.ensure().check_mod_type_wf(module);
+        });
     });
     tcx.sess.abort_if_errors();
     tcx.sess.time("missing_docs", || rustc_lint::check_crate(tcx));

tests/rustdoc-json/enums/field_hidden.rs

@@ -1,7 +1,10 @@
 // Regression test for <https://github.com/rust-lang/rust/issues/100529>.
 
 #![no_core]
-#![feature(no_core)]
+#![feature(no_core, lang_items)]
+
+#[lang = "sized"]
+trait Sized {}
 
 // @has "$.index[*][?(@.name=='ParseError')]"
 // @has "$.index[*][?(@.name=='UnexpectedEndTag')]"

tests/rustdoc-json/enums/kind.rs

@@ -1,8 +1,11 @@
 // ignore-tidy-linelength
 
-#![feature(no_core)]
+#![feature(no_core, lang_items)]
 #![no_core]
 
+#[lang = "sized"]
+trait Sized {}
+
 pub enum Foo {
     // @set Unit = "$.index[*][?(@.name=='Unit')].id"
     // @is "$.index[*][?(@.name=='Unit')].inner.variant.kind" '"plain"'

tests/rustdoc-json/enums/tuple_fields_hidden.rs

@@ -1,6 +1,9 @@
-#![feature(no_core)]
+#![feature(no_core, lang_items)]
 #![no_core]
 
+#[lang = "sized"]
+trait Sized {}
+
 // @set 1.1.0 = "$.index[*][?(@.docs=='1.1.0')].id"
 // @set 2.1.0 = "$.index[*][?(@.docs=='2.1.0')].id"
 // @set 2.1.1 = "$.index[*][?(@.docs=='2.1.1')].id"

tests/rustdoc-json/generic-associated-types/gats.rs

@@ -1,11 +1,14 @@
 // ignore-tidy-linelength
 
 #![no_core]
-#![feature(lang_items, no_core)]
+#![feature(lang_items, no_core, arbitrary_self_types)]
 
 #[lang = "sized"]
 pub trait Sized {}
 
+#[lang = "receiver"]
+pub trait Receiver {}
+
 pub trait Display {}
 
 pub trait LendingIterator {

tests/rustdoc-json/impls/auto.rs

@@ -1,9 +1,12 @@
-#![feature(no_core, auto_traits, lang_items)]
+#![feature(no_core, auto_traits, lang_items, arbitrary_self_types)]
 #![no_core]
 
 #[lang = "sized"]
 trait Sized {}
 
+#[lang = "receiver"]
+pub trait Receiver {}
+
 pub auto trait Bar {}
 
 /// has span
@@ -12,8 +15,8 @@ impl Foo {
 }
 
 // Testing spans, so all tests below code
-// @is "$.index[*][?(@.docs=='has span')].span.begin" "[10, 0]"
-// @is "$.index[*][?(@.docs=='has span')].span.end" "[12, 1]"
+// @is "$.index[*][?(@.docs=='has span')].span.begin" "[13, 0]"
+// @is "$.index[*][?(@.docs=='has span')].span.end" "[15, 1]"
 // FIXME: this doesn't work due to https://github.com/freestrings/jsonpath/issues/91
 // is "$.index[*][?(@.inner.impl.synthetic==true)].span" null
 pub struct Foo;

tests/rustdoc-json/type/inherent_associated_type_bound.rs

@@ -16,5 +16,5 @@ pub struct Carrier<'a>(&'a ());
 pub fn user(_: for<'b> fn(Carrier<'b>::Focus<i32>)) {}
 
 impl<'a> Carrier<'a> {
-    pub type Focus<T> = &'a mut T;
+    pub type Focus<T> = &'a mut T where T: 'a;
 }

tests/rustdoc-ui/error-in-impl-trait/infinite-recursive-type-2.rs

@@ -1,7 +1,6 @@
-// check-pass
-
 pub fn f() -> impl Sized {
     pub enum E {
+        //~^ ERROR: recursive type
         V(E),
     }
 

tests/rustdoc-ui/error-in-impl-trait/infinite-recursive-type-2.stderr

@@ -0,0 +1,17 @@
+error[E0072]: recursive type `f::E` has infinite size
+  --> $DIR/infinite-recursive-type-2.rs:2:5
+   |
+LL |     pub enum E {
+   |     ^^^^^^^^^^
+LL |
+LL |         V(E),
+   |           - recursive without indirection
+   |
+help: insert some indirection (e.g., a `Box`, `Rc`, or `&`) to break the cycle
+   |
+LL |         V(Box<E>),
+   |           ++++ +
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0072`.