diff --git a/llvm/tools/llvm-ml/llvm-ml.cpp b/llvm/tools/llvm-ml/llvm-ml.cpp
index 38c4861..1b30f3e 100644
--- a/llvm/tools/llvm-ml/llvm-ml.cpp
+++ b/llvm/tools/llvm-ml/llvm-ml.cpp
@@ -278,7 +278,7 @@
   }
   for (const auto &Arg : DebugPrefixMap) {
     const auto &KV = StringRef(Arg).split('=');
-    Ctx.addDebugPrefixMapEntry(KV.first, KV.second);
+    Ctx.addDebugPrefixMapEntry(std::string(KV.first), std::string(KV.second));
   }
   if (!MainFileName.empty())
     Ctx.setMainFileName(MainFileName);