Ignore "non-real" type Res in rustdoc intra doc link resolution

compiler/rustc_resolve/src/late.rs

@@ -17,7 +17,7 @@ use rustc_ast::*;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap};
 use rustc_errors::{Applicability, DiagnosticArgValue, DiagnosticId, IntoDiagnosticArg};
 use rustc_hir::def::Namespace::{self, *};
-use rustc_hir::def::{self, CtorKind, DefKind, LifetimeRes, PartialRes, PerNS};
+use rustc_hir::def::{self, CtorKind, DefKind, LifetimeRes, NonMacroAttrKind, PartialRes, PerNS};
 use rustc_hir::def_id::{DefId, LocalDefId, CRATE_DEF_ID, LOCAL_CRATE};
 use rustc_hir::{BindingAnnotation, PrimTy, TraitCandidate};
 use rustc_middle::middle::resolve_bound_vars::Set1;
@@ -4287,12 +4287,12 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
         }
     }
 
-    fn resolve_and_cache_rustdoc_path(&mut self, path_str: &str, ns: Namespace) -> bool {
+    fn resolve_and_cache_rustdoc_path(&mut self, path_str: &str, ns: Namespace) -> Option<Res> {
         // FIXME: This caching may be incorrect in case of multiple `macro_rules`
         // items with the same name in the same module.
         // Also hygiene is not considered.
         let mut doc_link_resolutions = std::mem::take(&mut self.r.doc_link_resolutions);
-        let res = doc_link_resolutions
+        let res = *doc_link_resolutions
             .entry(self.parent_scope.module.nearest_parent_mod().expect_local())
             .or_default()
             .entry((Symbol::intern(path_str), ns))
@@ -4307,8 +4307,7 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
                     return None;
                 }
                 res
-            })
+            });
-            .is_some();
         self.r.doc_link_resolutions = doc_link_resolutions;
         res
     }
@@ -4343,8 +4342,10 @@ impl<'a: 'ast, 'b, 'ast, 'tcx> LateResolutionVisitor<'a, 'b, 'ast, 'tcx> {
             let mut any_resolved = false;
             let mut need_assoc = false;
             for ns in [TypeNS, ValueNS, MacroNS] {
-                if self.resolve_and_cache_rustdoc_path(&path_str, ns) {
+                if let Some(res) = self.resolve_and_cache_rustdoc_path(&path_str, ns) {
-                    any_resolved = true;
+                    // Rustdoc ignores tool attribute resolutions and attempts
+                    // to resolve their prefixes for diagnostics.
+                    any_resolved = !matches!(res, Res::NonMacroAttr(NonMacroAttrKind::Tool));
                 } else if ns != MacroNS {
                     need_assoc = true;
                 }

src/librustdoc/passes/collect_intra_doc_links.rs

@@ -149,7 +149,7 @@ impl TryFrom<ResolveRes> for Res {
             Def(kind, id) => Ok(Res::Def(kind, id)),
             PrimTy(prim) => Ok(Res::Primitive(PrimitiveType::from_hir(prim))),
             // e.g. `#[derive]`
-            NonMacroAttr(..) | Err => Result::Err(()),
+            ToolMod | NonMacroAttr(..) | Err => Result::Err(()),
             other => bug!("unrecognized res {:?}", other),
         }
     }