3 files changed, 32 insertions, 14 deletions
diff --git a/compiler/rustc_ast_lowering/src/item.rs b/compiler/rustc_ast_lowering/src/item.rs
index d3aacaa15a8..d1a2ddbdb34 100644
--- a/compiler/rustc_ast_lowering/src/item.rs
+++ b/compiler/rustc_ast_lowering/src/item.rs
@@ -3,10 +3,11 @@ use rustc_ast::ptr::P;
 use rustc_ast::visit::AssocCtxt;
 use rustc_ast::*;
 use rustc_errors::ErrorGuaranteed;
-use rustc_hir::def::{DefKind, Res};
+use rustc_hir::def::{DefKind, PerNS, Res};
 use rustc_hir::def_id::{CRATE_DEF_ID, LocalDefId};
 use rustc_hir::{self as hir, HirId, LifetimeSource, PredicateOrigin};
 use rustc_index::{IndexSlice, IndexVec};
+use rustc_middle::span_bug;
 use rustc_middle::ty::{ResolverAstLowering, TyCtxt};
 use rustc_span::edit_distance::find_best_match_for_name;
 use rustc_span::{DUMMY_SP, DesugaringKind, Ident, Span, Symbol, kw, sym};
@@ -527,7 +528,22 @@ impl<'hir> LoweringContext<'_, 'hir> {
             }
             UseTreeKind::Glob => {
                 let res = self.expect_full_res(id);
-                let res = smallvec![self.lower_res(res)];
+                let res = self.lower_res(res);
+                // Put the result in the appropriate namespace.
+                let res = match res {
+                    Res::Def(DefKind::Mod | DefKind::Trait, _) => {
+                        PerNS { type_ns: Some(res), value_ns: None, macro_ns: None }
+                    }
+                    Res::Def(DefKind::Enum, _) => {
+                        PerNS { type_ns: None, value_ns: Some(res), macro_ns: None }
+                    }
+                    Res::Err => {
+                        // Propagate the error to all namespaces, just to be sure.
+                        let err = Some(Res::Err);
+                        PerNS { type_ns: err, value_ns: err, macro_ns: err }
+                    }
+                    _ => span_bug!(path.span, "bad glob res {:?}", res),
+                };
                 let path = Path { segments, span: path.span, tokens: None };
                 let path = self.lower_use_path(res, &path, ParamMode::Explicit);
                 hir::ItemKind::Use(path, hir::UseKind::Glob)
@@ -601,7 +617,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                 } else {
                     // For non-empty lists we can just drop all the data, the prefix is already
                     // present in HIR as a part of nested imports.
-                    self.arena.alloc(hir::UsePath { res: smallvec![], segments: &[], span })
+                    self.arena.alloc(hir::UsePath { res: PerNS::default(), segments: &[], span })
                 };
                 hir::ItemKind::Use(path, hir::UseKind::ListStem)
             }
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index 422e79ca82f..f41627e479f 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -64,7 +64,7 @@ use rustc_middle::ty::{ResolverAstLowering, TyCtxt};
 use rustc_session::parse::{add_feature_diagnostics, feature_err};
 use rustc_span::symbol::{Ident, Symbol, kw, sym};
 use rustc_span::{DUMMY_SP, DesugaringKind, Span};
-use smallvec::{SmallVec, smallvec};
+use smallvec::SmallVec;
 use thin_vec::ThinVec;
 use tracing::{debug, instrument, trace};
 
@@ -705,14 +705,16 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
         self.resolver.get_partial_res(id).map_or(Res::Err, |pr| pr.expect_full_res())
     }
 
-    fn lower_import_res(&mut self, id: NodeId, span: Span) -> SmallVec<[Res; 3]> {
-        let res = self.resolver.get_import_res(id).present_items();
-        let res: SmallVec<_> = res.map(|res| self.lower_res(res)).collect();
-        if res.is_empty() {
+    fn lower_import_res(&mut self, id: NodeId, span: Span) -> PerNS<Option<Res>> {
+        let per_ns = self.resolver.get_import_res(id);
+        let per_ns = per_ns.map(|res| res.map(|res| self.lower_res(res)));
+        if per_ns.is_empty() {
+            // Propagate the error to all namespaces, just to be sure.
             self.dcx().span_delayed_bug(span, "no resolution for an import");
-            return smallvec![Res::Err];
+            let err = Some(Res::Err);
+            return PerNS { type_ns: err, value_ns: err, macro_ns: err };
         }
-        res
+        per_ns
     }
 
     fn make_lang_item_qpath(
diff --git a/compiler/rustc_ast_lowering/src/path.rs b/compiler/rustc_ast_lowering/src/path.rs
index 5cda64ce7b4..c80ef275c80 100644
--- a/compiler/rustc_ast_lowering/src/path.rs
+++ b/compiler/rustc_ast_lowering/src/path.rs
@@ -1,13 +1,13 @@
 use std::sync::Arc;
 
 use rustc_ast::{self as ast, *};
-use rustc_hir::def::{DefKind, PartialRes, Res};
+use rustc_hir::def::{DefKind, PartialRes, PerNS, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::{self as hir, GenericArg};
 use rustc_middle::{span_bug, ty};
 use rustc_session::parse::add_feature_diagnostics;
 use rustc_span::{BytePos, DUMMY_SP, DesugaringKind, Ident, Span, Symbol, sym};
-use smallvec::{SmallVec, smallvec};
+use smallvec::smallvec;
 use tracing::{debug, instrument};
 
 use super::errors::{
@@ -226,11 +226,11 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
 
     pub(crate) fn lower_use_path(
         &mut self,
-        res: SmallVec<[Res; 3]>,
+        res: PerNS<Option<Res>>,
         p: &Path,
         param_mode: ParamMode,
     ) -> &'hir hir::UsePath<'hir> {
-        assert!((1..=3).contains(&res.len()));
+        assert!(!res.is_empty());
         self.arena.alloc(hir::UsePath {
             res,
             segments: self.arena.alloc_from_iter(p.segments.iter().map(|segment| {