diff --git a/clang/include/clang/Basic/Module.h b/clang/include/clang/Basic/Module.h
--- a/clang/include/clang/Basic/Module.h
+++ b/clang/include/clang/Basic/Module.h
@@ -15,6 +15,7 @@
 #ifndef LLVM_CLANG_BASIC_MODULE_H
 #define LLVM_CLANG_BASIC_MODULE_H
 
+#include "clang/Basic/DirectoryEntry.h"
 #include "clang/Basic/FileEntry.h"
 #include "clang/Basic/SourceLocation.h"
 #include "llvm/ADT/ArrayRef.h"
@@ -44,8 +45,6 @@
 
 namespace clang {
 
-class DirectoryEntry;
-class FileEntry;
 class FileManager;
 class LangOptions;
 class TargetInfo;
@@ -134,7 +133,7 @@
   std::string PresumedModuleMapFile;
 
   /// The umbrella header or directory.
-  const void *Umbrella = nullptr;
+  llvm::PointerUnion<const FileEntry *, const DirectoryEntry *> Umbrella;
 
   /// The module signature.
   ASTFileSignature Signature;
@@ -303,9 +302,6 @@
   /// to a regular (public) module map.
   unsigned ModuleMapIsPrivate : 1;
 
-  /// Whether Umbrella is a directory or header.
-  unsigned HasUmbrellaDir : 1;
-
   /// Describes the visibility of the various names within a
   /// particular module.
   enum NameVisibilityKind {
@@ -548,15 +544,16 @@
   /// Retrieve the header that serves as the umbrella header for this
   /// module.
   Header getUmbrellaHeader() const {
-    if (!HasUmbrellaDir)
-      return Header{UmbrellaAsWritten,
-                    static_cast<const FileEntry *>(Umbrella)};
+    if (auto *FE = Umbrella.dyn_cast<const FileEntry *>())
+      return Header{UmbrellaAsWritten, FE};
     return Header{};
   }
 
   /// Determine whether this module has an umbrella directory that is
   /// not based on an umbrella header.
-  bool hasUmbrellaDir() const { return Umbrella && HasUmbrellaDir; }
+  bool hasUmbrellaDir() const {
+    return Umbrella && Umbrella.is<const DirectoryEntry *>();
+  }
 
   /// Add a top-level header associated with this module.
   void addTopHeader(const FileEntry *File);
diff --git a/clang/lib/Basic/Module.cpp b/clang/lib/Basic/Module.cpp
--- a/clang/lib/Basic/Module.cpp
+++ b/clang/lib/Basic/Module.cpp
@@ -44,7 +44,7 @@
       InferSubmodules(false), InferExplicitSubmodules(false),
       InferExportWildcard(false), ConfigMacrosExhaustive(false),
       NoUndeclaredIncludes(false), ModuleMapIsPrivate(false),
-      HasUmbrellaDir(false), NameVisibility(Hidden) {
+      NameVisibility(Hidden) {
   if (Parent) {
     IsAvailable = Parent->isAvailable();
     IsUnimportable = Parent->isUnimportable();
@@ -247,7 +247,7 @@
   if (Header U = getUmbrellaHeader())
     return {"", U.Entry->getDir()};
 
-  return {UmbrellaAsWritten, static_cast<const DirectoryEntry *>(Umbrella)};
+  return {UmbrellaAsWritten, Umbrella.dyn_cast<const DirectoryEntry *>()};
 }
 
 void Module::addTopHeader(const FileEntry *File) {
diff --git a/clang/lib/Lex/ModuleMap.cpp b/clang/lib/Lex/ModuleMap.cpp
--- a/clang/lib/Lex/ModuleMap.cpp
+++ b/clang/lib/Lex/ModuleMap.cpp
@@ -1125,7 +1125,6 @@
                                   Twine NameAsWritten) {
   Headers[UmbrellaHeader].push_back(KnownHeader(Mod, NormalHeader));
   Mod->Umbrella = UmbrellaHeader;
-  Mod->HasUmbrellaDir = false;
   Mod->UmbrellaAsWritten = NameAsWritten.str();
   UmbrellaDirs[UmbrellaHeader->getDir()] = Mod;
 
@@ -1137,7 +1136,6 @@
 void ModuleMap::setUmbrellaDir(Module *Mod, const DirectoryEntry *UmbrellaDir,
                                Twine NameAsWritten) {
   Mod->Umbrella = UmbrellaDir;
-  Mod->HasUmbrellaDir = true;
   Mod->UmbrellaAsWritten = NameAsWritten.str();
   UmbrellaDirs[UmbrellaDir] = Mod;
 }