diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index 8220a6e..c3f19a3 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -408,7 +408,9 @@
   ModuleManager = createPCHExternalASTSource(
       Path, getHeaderSearchOpts().Sysroot, DisablePCHValidation,
       AllowPCHWithCompilerErrors, getPreprocessor(), getASTContext(),
-      getPCHContainerReader(), DeserializationListener,
+      getPCHContainerReader(),
+      getFrontendOpts().ModuleFileExtensions,
+      DeserializationListener,
       OwnDeserializationListener, Preamble,
       getFrontendOpts().UseGlobalModuleIndex);
 }
@@ -417,15 +419,16 @@
     StringRef Path, StringRef Sysroot, bool DisablePCHValidation,
     bool AllowPCHWithCompilerErrors, Preprocessor &PP, ASTContext &Context,
     const PCHContainerReader &PCHContainerRdr,
+    ArrayRef<IntrusiveRefCntPtr<ModuleFileExtension>> Extensions,
     void *DeserializationListener, bool OwnDeserializationListener,
     bool Preamble, bool UseGlobalModuleIndex) {
   HeaderSearchOptions &HSOpts = PP.getHeaderSearchInfo().getHeaderSearchOpts();
 
   IntrusiveRefCntPtr<ASTReader> Reader(new ASTReader(
-      PP, Context, PCHContainerRdr, Sysroot.empty() ? "" : Sysroot.data(),
-      DisablePCHValidation, AllowPCHWithCompilerErrors,
-      /*AllowConfigurationMismatch*/ false, HSOpts.ModulesValidateSystemHeaders,
-      UseGlobalModuleIndex));
+      PP, Context, PCHContainerRdr, Extensions,
+      Sysroot.empty() ? "" : Sysroot.data(), DisablePCHValidation,
+      AllowPCHWithCompilerErrors, /*AllowConfigurationMismatch*/ false,
+      HSOpts.ModulesValidateSystemHeaders, UseGlobalModuleIndex));
 
   // We need the external source to be set up before we read the AST, because
   // eagerly-deserialized declarations may use it.
@@ -1267,6 +1270,7 @@
                                                  *FrontendTimerGroup);
     ModuleManager = new ASTReader(
         getPreprocessor(), getASTContext(), getPCHContainerReader(),
+        getFrontendOpts().ModuleFileExtensions,
         Sysroot.empty() ? "" : Sysroot.c_str(), PPOpts.DisablePCHValidation,
         /*AllowASTWithCompilerErrors=*/false,
         /*AllowConfigurationMismatch=*/false,