diff --git a/include/llvm/MC/MCDwarf.h b/include/llvm/MC/MCDwarf.h
index 5b972109eb4..63040cb194e 100644
--- a/include/llvm/MC/MCDwarf.h
+++ b/include/llvm/MC/MCDwarf.h
@@ -224,7 +224,7 @@ public:
 
   Expected<unsigned> tryGetFile(StringRef &Directory, StringRef &FileName,
                                 Optional<MD5::MD5Result> Checksum,
-                                Optional<StringRef> &Source,
+                                Optional<StringRef> Source,
                                 unsigned FileNumber = 0);
   std::pair<MCSymbol *, MCSymbol *>
   Emit(MCStreamer *MCOS, MCDwarfLineTableParams Params,
@@ -293,7 +293,7 @@ public:
                                 Optional<StringRef> Source,
                                 unsigned FileNumber = 0);
   unsigned getFile(StringRef &Directory, StringRef &FileName,
-                   Optional<MD5::MD5Result> Checksum, Optional<StringRef> &Source,
+                   Optional<MD5::MD5Result> Checksum, Optional<StringRef> Source,
                    unsigned FileNumber = 0) {
     return cantFail(tryGetFile(Directory, FileName, Checksum, Source,
                                FileNumber));
diff --git a/lib/MC/MCDwarf.cpp b/lib/MC/MCDwarf.cpp
index ebc45f4c427..a95d97b70d9 100644
--- a/lib/MC/MCDwarf.cpp
+++ b/lib/MC/MCDwarf.cpp
@@ -546,7 +546,7 @@ Expected<unsigned>
 MCDwarfLineTableHeader::tryGetFile(StringRef &Directory,
                                    StringRef &FileName,
                                    Optional<MD5::MD5Result> Checksum,
-                                   Optional<StringRef> &Source,
+                                   Optional<StringRef> Source,
                                    unsigned FileNumber) {
   if (Directory == CompilationDir)
     Directory = "";