diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index 93cd932a6187..51d930073dc8 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -535,7 +535,7 @@ ASTDeclReader::RedeclarableResult ASTDeclReader::VisitTagDecl(TagDecl *TD) {
     TypedefNameForLinkage = Reader.GetIdentifierInfo(F, Record, Idx);
     break;
   case 3: // DeclaratorForAnonDecl
-    TD->NamedDeclOrQualifier = ReadDeclAs<NamedDecl>(Record, Idx);
+    NamedDeclForTagDecl = ReadDeclID(Record, Idx);
     break;
   default:
     llvm_unreachable("unexpected tag info kind");
diff --git a/clang/test/Modules/Inputs/cxx-templates-a.h b/clang/test/Modules/Inputs/cxx-templates-a.h
index c2ce74d195b6..92333b377a19 100644
--- a/clang/test/Modules/Inputs/cxx-templates-a.h
+++ b/clang/test/Modules/Inputs/cxx-templates-a.h
@@ -89,3 +89,11 @@ typedef PartiallyInstantiatePartialSpec<int*> PartiallyInstantiatePartialSpecHel
 void InstantiateWithAliasTemplate(WithAliasTemplate<int>::X<char>);
 inline int InstantiateWithAnonymousDeclsA(WithAnonymousDecls<int> x) { return (x.k ? x.a : x.b) + (x.k ? x.s.c : x.s.d) + x.e; }
 inline int InstantiateWithAnonymousDeclsB2(WithAnonymousDecls<char> x);
+
+
+template<typename T1 = int>
+struct MergeAnonUnionMember {
+  MergeAnonUnionMember() { (void)values.t1; }
+  union { int t1; } values;
+};
+inline MergeAnonUnionMember<> maum_a() { return {}; }
diff --git a/clang/test/Modules/Inputs/cxx-templates-c.h b/clang/test/Modules/Inputs/cxx-templates-c.h
index 6daffadc6ced..6b4c50667065 100644
--- a/clang/test/Modules/Inputs/cxx-templates-c.h
+++ b/clang/test/Modules/Inputs/cxx-templates-c.h
@@ -11,3 +11,10 @@ template<typename T> struct MergeTemplateDefinitions {
   static constexpr int g();
 };
 template<typename T> constexpr int MergeTemplateDefinitions<T>::g() { return 2; }
+
+template<typename T1 = int>
+struct MergeAnonUnionMember {
+  MergeAnonUnionMember() { (void)values.t1; }
+  union { int t1; } values;
+};
+inline MergeAnonUnionMember<> maum_c() { return {}; }
diff --git a/clang/test/Modules/cxx-templates.cpp b/clang/test/Modules/cxx-templates.cpp
index 3833e995c52e..b29923366513 100644
--- a/clang/test/Modules/cxx-templates.cpp
+++ b/clang/test/Modules/cxx-templates.cpp
@@ -144,6 +144,8 @@ MergeSpecializations<double>::explicitly_specialized_in_b spec_in_b_2;
 MergeSpecializations<bool>::explicitly_specialized_in_c spec_in_c_2;
 #endif
 
+MergeAnonUnionMember<> maum_main;
+
 using AliasTemplateMergingTest = WithAliasTemplate<int>::X<char>;
 
 int AnonymousDeclsMergingTest(WithAnonymousDecls<int> WAD, WithAnonymousDecls<char> WADC) {