1 files changed, 11 insertions, 1 deletions
diff --git a/clang/lib/Sema/TreeTransform.h b/clang/lib/Sema/TreeTransform.h
index 31d69cbac35..81c56c2f2c6 100644
--- a/clang/lib/Sema/TreeTransform.h
+++ b/clang/lib/Sema/TreeTransform.h
@@ -9128,8 +9128,18 @@ TreeTransform<Derived>::TransformUnresolvedLookupExpr(
 
   // If we have neither explicit template arguments, nor the template keyword,
   // it's a normal declaration name.
-  if (!Old->hasExplicitTemplateArgs() && !TemplateKWLoc.isValid())
+  if (!Old->hasExplicitTemplateArgs() && !TemplateKWLoc.isValid()) {
+    // If an UnresolvedLookupExpr resolved to an instance member, that's an
+    // error.
+    NamedDecl *D = R.getAsSingle<NamedDecl>();
+    if (D && D->isCXXInstanceMember()) {
+      SemaRef.DiagnoseInstanceReference(SS, D, Old->getNameInfo());
+      R.clear();
+      return ExprError();
+    }
+
     return getDerived().RebuildDeclarationNameExpr(SS, R, Old->requiresADL());
+  }
 
   // If we have template arguments, rebuild them, then rebuild the
   // templateid expression.