Index: clang/include/clang/Basic/FileManager.h
===================================================================
--- clang/include/clang/Basic/FileManager.h
+++ clang/include/clang/Basic/FileManager.h
@@ -317,8 +317,7 @@
   /// Open the specified file as a MemoryBuffer, returning a new
   /// MemoryBuffer if successful, otherwise returning null.
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
-  getBufferForFile(const FileEntry *Entry, bool isVolatile = false,
-                   bool ShouldCloseOpenFile = true);
+  getBufferForFile(const FileEntry *Entry, bool isVolatile = false);
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
   getBufferForFile(StringRef Filename, bool isVolatile = false) {
     return getBufferForFileImpl(Filename, /*FileSize=*/-1, isVolatile);
Index: clang/lib/Basic/FileManager.cpp
===================================================================
--- clang/lib/Basic/FileManager.cpp
+++ clang/lib/Basic/FileManager.cpp
@@ -426,8 +426,7 @@
 }
 
 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
-FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile,
-                              bool ShouldCloseOpenFile) {
+FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile) {
   uint64_t FileSize = Entry->getSize();
   // If there's a high enough chance that the file have changed since we
   // got its size, force a stat before opening it.
@@ -440,10 +439,7 @@
     auto Result =
         Entry->File->getBuffer(Filename, FileSize,
                                /*RequiresNullTerminator=*/true, isVolatile);
-    // FIXME: we need a set of APIs that can make guarantees about whether a
-    // FileEntry is open or not.
-    if (ShouldCloseOpenFile)
-      Entry->closeFile();
+    Entry->closeFile();
     return Result;
   }
 
Index: clang/lib/Serialization/ModuleManager.cpp
===================================================================
--- clang/lib/Serialization/ModuleManager.cpp
+++ clang/lib/Serialization/ModuleManager.cpp
@@ -185,9 +185,7 @@
       Buf = llvm::MemoryBuffer::getSTDIN();
     } else {
       // Get a buffer of the file and close the file descriptor when done.
-      Buf = FileMgr.getBufferForFile(NewModule->File,
-                                     /*isVolatile=*/false,
-                                     /*ShouldClose=*/true);
+      Buf = FileMgr.getBufferForFile(NewModule->File, /*isVolatile=*/false);
     }
 
     if (!Buf) {