Check signature of intrinsics with fallback bodies

Author: oli-obk

compiler/rustc_hir_analysis/src/check/check.rs

@@ -471,7 +471,18 @@ pub(crate) fn check_item_type(tcx: TyCtxt<'_>, def_id: LocalDefId) {
         DefKind::Enum => {
             check_enum(tcx, def_id);
         }
-        DefKind::Fn => {} // entirely within check_item_body
+        DefKind::Fn => {
+            if let Some(name) = tcx.intrinsic(def_id) {
+                intrinsic::check_intrinsic_type(
+                    tcx,
+                    def_id,
+                    tcx.def_ident_span(def_id).unwrap(),
+                    name,
+                    Abi::Rust,
+                )
+            }
+            // Everything else is checked entirely within check_item_body
+        }
         DefKind::Impl { of_trait } => {
             if of_trait && let Some(impl_trait_ref) = tcx.impl_trait_ref(def_id) {
                 check_impl_items_against_trait(tcx, def_id, impl_trait_ref.instantiate_identity());
@@ -534,7 +545,13 @@ pub(crate) fn check_item_type(tcx: TyCtxt<'_>, def_id: LocalDefId) {
             match abi {
                 Abi::RustIntrinsic => {
                     for item in items {
-                        intrinsic::check_intrinsic_type(tcx, item.id.owner_id.def_id, item.span);
+                        intrinsic::check_intrinsic_type(
+                            tcx,
+                            item.id.owner_id.def_id,
+                            item.span,
+                            item.ident.name,
+                            abi,
+                        );
                     }
                 }
 

compiler/rustc_hir_analysis/src/check/intrinsic.rs

@@ -26,7 +26,8 @@ fn equate_intrinsic_type<'tcx>(
     sig: ty::PolyFnSig<'tcx>,
 ) {
     let (own_counts, span) = match tcx.hir_node_by_def_id(def_id) {
-        hir::Node::ForeignItem(hir::ForeignItem {
+        hir::Node::Item(hir::Item { kind: hir::ItemKind::Fn(_, generics, _), .. })
+        | hir::Node::ForeignItem(hir::ForeignItem {
             kind: hir::ForeignItemKind::Fn(.., generics),
             ..
         }) => {
@@ -135,9 +136,14 @@ pub fn intrinsic_operation_unsafety(tcx: TyCtxt<'_>, intrinsic_id: LocalDefId) -
 
 /// Remember to add all intrinsics here, in `compiler/rustc_codegen_llvm/src/intrinsic.rs`,
 /// and in `library/core/src/intrinsics.rs`.
-pub fn check_intrinsic_type(tcx: TyCtxt<'_>, intrinsic_id: LocalDefId, span: Span) {
+pub fn check_intrinsic_type(
+    tcx: TyCtxt<'_>,
+    intrinsic_id: LocalDefId,
+    span: Span,
+    intrinsic_name: Symbol,
+    abi: Abi,
+) {
     let param = |n| Ty::new_param(tcx, n, Symbol::intern(&format!("P{n}")));
-    let intrinsic_name = tcx.item_name(intrinsic_id.into());
     let name_str = intrinsic_name.as_str();
 
     let bound_vars = tcx.mk_bound_variable_kinds(&[
@@ -468,7 +474,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, intrinsic_id: LocalDefId, span: Spa
 
             sym::black_box => (1, 0, vec![param(0)], param(0)),
 
-            sym::is_val_statically_known => (1, 0, vec![param(0)], tcx.types.bool),
+            sym::is_val_statically_known => (1, 1, vec![param(0)], tcx.types.bool),
 
             sym::const_eval_select => (4, 0, vec![param(0), param(1), param(2)], param(3)),
 
@@ -483,7 +489,7 @@ pub fn check_intrinsic_type(tcx: TyCtxt<'_>, intrinsic_id: LocalDefId, span: Spa
         };
         (n_tps, 0, n_cts, inputs, output, unsafety)
     };
-    let sig = tcx.mk_fn_sig(inputs, output, false, unsafety, Abi::RustIntrinsic);
+    let sig = tcx.mk_fn_sig(inputs, output, false, unsafety, abi);
     let sig = ty::Binder::bind_with_vars(sig, bound_vars);
     equate_intrinsic_type(tcx, span, intrinsic_id, n_tps, n_lts, n_cts, sig)
 }