Index: lldb/include/lldb/Symbol/Type.h
===================================================================
--- lldb/include/lldb/Symbol/Type.h
+++ lldb/include/lldb/Symbol/Type.h
@@ -195,12 +195,7 @@
   void SetEncodingType(Type *encoding_type) { m_encoding_type = encoding_type; }
 
   uint32_t GetEncodingMask();
-
-  bool IsCompleteObjCClass() { return m_is_complete_objc_class; }
-
-  void SetIsCompleteObjCClass(bool is_complete_objc_class) {
-    m_is_complete_objc_class = is_complete_objc_class;
-  }
+  uint32_t &GetPayload() { return m_payload; }
 
 protected:
   ConstString m_name;
@@ -215,7 +210,8 @@
   Declaration m_decl;
   CompilerType m_compiler_type;
   ResolveState m_compiler_type_resolve_state;
-  bool m_is_complete_objc_class;
+  /// Language-specific flags.
+  uint32_t m_payload = 0;
 
   Type *GetEncodingType();
 
Index: lldb/source/Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.cpp
===================================================================
--- lldb/source/Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.cpp
+++ lldb/source/Plugins/LanguageRuntime/ObjC/ObjCLanguageRuntime.cpp
@@ -129,7 +129,7 @@
 
       if (TypeSystemClang::IsObjCObjectOrInterfaceType(
               type_sp->GetForwardCompilerType())) {
-        if (type_sp->IsCompleteObjCClass()) {
+        if (TypePayloadClang(type_sp->GetPayload()).IsCompleteObjCClass()) {
           m_complete_class_cache[name] = type_sp;
           return type_sp;
         }
Index: lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
===================================================================
--- lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
+++ lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp
@@ -1627,7 +1627,8 @@
                                    Type::eEncodingIsUID, &attrs.decl,
                                    clang_type, Type::ResolveState::Forward);
 
-  type_sp->SetIsCompleteObjCClass(attrs.is_complete_objc_class);
+  TypePayloadClang(type_sp->GetPayload())
+      .SetIsCompleteObjCClass(attrs.is_complete_objc_class);
 
   // Add our type to the unique type map so we don't end up creating many
   // copies of the same type over and over in the ASTContext for our
Index: lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
===================================================================
--- lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
+++ lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.h
@@ -33,6 +33,7 @@
 #include "lldb/Symbol/TypeSystem.h"
 #include "lldb/Target/Target.h"
 #include "lldb/Utility/ConstString.h"
+#include "lldb/Utility/Flags.h"
 #include "lldb/Utility/Log.h"
 #include "lldb/Utility/Logging.h"
 #include "lldb/lldb-enumerations.h"
@@ -40,12 +41,41 @@
 class DWARFASTParserClang;
 class PDBASTParser;
 
+namespace clang {
+  class HeaderSearch;
+  class ModuleMap;
+}
+
 namespace lldb_private {
 
 class ClangASTMetadata;
 class ClangASTSource;
 class Declaration;
 
+/// The implementation of lldb::Type's m_payload field for TypeSystemClang.
+class TypePayloadClang {
+  uint32_t &m_payload;
+public:
+  TypePayloadClang(uint32_t &opaque_payload) : m_payload(opaque_payload) {}
+  /// Clang-specific functions. As more of these get added we may want
+  /// to factor this into typesystem-specific subclasses.
+  /// \{
+  static constexpr unsigned ObjCClassBit = 1 << 31;
+  bool IsCompleteObjCClass() { return Flags(m_payload).Test(ObjCClassBit); }
+  void SetIsCompleteObjCClass(bool is_complete_objc_class) {
+    m_payload = is_complete_objc_class ? Flags(m_payload).Set(ObjCClassBit)
+                                       : Flags(m_payload).Clear(ObjCClassBit);
+  }
+  unsigned GetOwningModuleID() { return Flags(m_payload).Clear(ObjCClassBit); }
+  void SetOwningModuleID(unsigned id) {
+    assert(id < ObjCClassBit);
+    bool is_complete = IsCompleteObjCClass();
+    m_payload = id;
+    SetIsCompleteObjCClass(is_complete);
+  }
+  /// \}
+};
+  
 /// A TypeSystem implementation based on Clang.
 ///
 /// This class uses a single clang::ASTContext as the backend for storing
Index: lldb/source/Symbol/Type.cpp
===================================================================
--- lldb/source/Symbol/Type.cpp
+++ lldb/source/Symbol/Type.cpp
@@ -148,10 +148,8 @@
       m_symbol_file(symbol_file), m_context(context), m_encoding_type(nullptr),
       m_encoding_uid(encoding_uid), m_encoding_uid_type(encoding_uid_type),
       m_decl(decl), m_compiler_type(compiler_type),
-      m_compiler_type_resolve_state(
-          compiler_type ? compiler_type_resolve_state
-                        : ResolveState::Unresolved),
-      m_is_complete_objc_class(false) {
+      m_compiler_type_resolve_state(compiler_type ? compiler_type_resolve_state
+                                                  : ResolveState::Unresolved) {
   if (byte_size) {
     m_byte_size = *byte_size;
     m_byte_size_has_value = true;