Index: include/llvm/Support/FileSystem.h
===================================================================
--- include/llvm/Support/FileSystem.h
+++ include/llvm/Support/FileSystem.h
@@ -666,6 +666,26 @@
 ///          platform-specific error_code.
 std::error_code status_known(const Twine &path, bool &result);
 
+enum OpenFlags : unsigned {
+  F_None = 0,
+
+  /// F_Excl - When opening a file, this flag makes raw_fd_ostream
+  /// report an error if the file already exists.
+  F_Excl = 1,
+
+  /// F_Append - When opening a file, if it already exists append to the
+  /// existing file instead of returning an error.  This may not be specified
+  /// with F_Excl.
+  F_Append = 2,
+
+  /// The file should be opened in text mode on platforms that make this
+  /// distinction.
+  F_Text = 4,
+
+  /// Open the file for read and write.
+  F_RW = 8
+};
+
 /// @brief Create a uniquely named file.
 ///
 /// Generates a unique path suitable for a temporary file and then opens it as a
@@ -689,7 +709,8 @@
 ///          otherwise a platform-specific error_code.
 std::error_code createUniqueFile(const Twine &Model, int &ResultFD,
                                  SmallVectorImpl<char> &ResultPath,
-                                 unsigned Mode = all_read | all_write);
+                                 unsigned Mode = all_read | all_write,
+                                 sys::fs::OpenFlags Flags = sys::fs::F_RW);
 
 /// @brief Simpler version for clients that don't want an open file.
 std::error_code createUniqueFile(const Twine &Model,
@@ -743,7 +764,8 @@
 /// running the assembler.
 std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
                                     int &ResultFD,
-                                    SmallVectorImpl<char> &ResultPath);
+                                    SmallVectorImpl<char> &ResultPath,
+                                    sys::fs::OpenFlags Flags = sys::fs::F_RW);
 
 /// @brief Simpler version for clients that don't want an open file.
 std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
@@ -752,26 +774,6 @@
 std::error_code createUniqueDirectory(const Twine &Prefix,
                                       SmallVectorImpl<char> &ResultPath);
 
-enum OpenFlags : unsigned {
-  F_None = 0,
-
-  /// F_Excl - When opening a file, this flag makes raw_fd_ostream
-  /// report an error if the file already exists.
-  F_Excl = 1,
-
-  /// F_Append - When opening a file, if it already exists append to the
-  /// existing file instead of returning an error.  This may not be specified
-  /// with F_Excl.
-  F_Append = 2,
-
-  /// The file should be opened in text mode on platforms that make this
-  /// distinction.
-  F_Text = 4,
-
-  /// Open the file for read and write.
-  F_RW = 8
-};
-
 inline OpenFlags operator|(OpenFlags A, OpenFlags B) {
   return OpenFlags(unsigned(A) | unsigned(B));
 }
Index: lib/Support/Path.cpp
===================================================================
--- lib/Support/Path.cpp
+++ lib/Support/Path.cpp
@@ -160,10 +160,11 @@
   FS_Name
 };
 
-static std::error_code createUniqueEntity(const Twine &Model, int &ResultFD,
-                                          SmallVectorImpl<char> &ResultPath,
-                                          bool MakeAbsolute, unsigned Mode,
-                                          FSEntity Type) {
+static std::error_code
+createUniqueEntity(const Twine &Model, int &ResultFD,
+                   SmallVectorImpl<char> &ResultPath, bool MakeAbsolute,
+                   unsigned Mode, FSEntity Type,
+                   sys::fs::OpenFlags Flags = sys::fs::F_None) {
   SmallString<128> ModelStorage;
   Model.toVector(ModelStorage);
 
@@ -196,7 +197,7 @@
   case FS_File: {
     if (std::error_code EC =
             sys::fs::openFileForWrite(Twine(ResultPath.begin()), ResultFD,
-                                      sys::fs::F_RW | sys::fs::F_Excl, Mode)) {
+                                      Flags | sys::fs::F_Excl, Mode)) {
       if (EC == errc::file_exists)
         goto retry_random_path;
       return EC;
@@ -750,8 +751,9 @@
 
 std::error_code createUniqueFile(const Twine &Model, int &ResultFd,
                                  SmallVectorImpl<char> &ResultPath,
-                                 unsigned Mode) {
-  return createUniqueEntity(Model, ResultFd, ResultPath, false, Mode, FS_File);
+                                 unsigned Mode, sys::fs::OpenFlags Flags) {
+  return createUniqueEntity(Model, ResultFd, ResultPath, false, Mode, FS_File,
+                            Flags);
 }
 
 std::error_code createUniqueFile(const Twine &Model,
@@ -845,28 +847,32 @@
 
 static std::error_code
 createTemporaryFile(const Twine &Model, int &ResultFD,
-                    llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type) {
+                    llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type,
+                    sys::fs::OpenFlags Flags) {
   SmallString<128> Storage;
   StringRef P = Model.toNullTerminatedStringRef(Storage);
   assert(P.find_first_of(separators(Style::native)) == StringRef::npos &&
          "Model must be a simple filename.");
   // Use P.begin() so that createUniqueEntity doesn't need to recreate Storage.
-  return createUniqueEntity(P.begin(), ResultFD, ResultPath,
-                            true, owner_read | owner_write, Type);
+  return createUniqueEntity(P.begin(), ResultFD, ResultPath, true,
+                            owner_read | owner_write, Type, Flags);
 }
 
 static std::error_code
 createTemporaryFile(const Twine &Prefix, StringRef Suffix, int &ResultFD,
-                    llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type) {
+                    llvm::SmallVectorImpl<char> &ResultPath, FSEntity Type,
+                    sys::fs::OpenFlags Flags = sys::fs::F_None) {
   const char *Middle = Suffix.empty() ? "-%%%%%%" : "-%%%%%%.";
   return createTemporaryFile(Prefix + Middle + Suffix, ResultFD, ResultPath,
-                             Type);
+                             Type, Flags);
 }
 
 std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,
                                     int &ResultFD,
-                                    SmallVectorImpl<char> &ResultPath) {
-  return createTemporaryFile(Prefix, Suffix, ResultFD, ResultPath, FS_File);
+                                    SmallVectorImpl<char> &ResultPath,
+                                    sys::fs::OpenFlags Flags) {
+  return createTemporaryFile(Prefix, Suffix, ResultFD, ResultPath, FS_File,
+                             Flags);
 }
 
 std::error_code createTemporaryFile(const Twine &Prefix, StringRef Suffix,