diff --git a/llvm/unittests/ADT/TripleTest.cpp b/llvm/unittests/ADT/TripleTest.cpp
index ef7f82d..ca00837 100644
--- a/llvm/unittests/ADT/TripleTest.cpp
+++ b/llvm/unittests/ADT/TripleTest.cpp
@@ -584,7 +584,7 @@
 }
 
 static std::string Join(StringRef A, StringRef B, StringRef C) {
-  std::string Str = A;
+  std::string Str = std::string(A);
   Str += '-';
   Str += B;
   Str += '-';
@@ -593,7 +593,7 @@
 }
 
 static std::string Join(StringRef A, StringRef B, StringRef C, StringRef D) {
-  std::string Str = A;
+  std::string Str = std::string(A);
   Str += '-';
   Str += B;
   Str += '-';