diff --git a/llvm/unittests/tools/llvm-exegesis/PerfHelperTest.cpp b/llvm/unittests/tools/llvm-exegesis/PerfHelperTest.cpp
index 7ff256f..5332b84 100644
--- a/llvm/unittests/tools/llvm-exegesis/PerfHelperTest.cpp
+++ b/llvm/unittests/tools/llvm-exegesis/PerfHelperTest.cpp
@@ -30,8 +30,8 @@
   Measure(
       makeArrayRef(SingleEvent),
       [&](const PerfEvent &Event, int64_t Value) {
-        CallbackEventName = Event.name();
-        CallbackEventNameFullyQualifed = Event.getPfmEventString();
+        CallbackEventName = std::string(Event.name());
+        CallbackEventNameFullyQualifed = std::string(Event.getPfmEventString());
         CallbackEventCycles = Value;
       },
       EmptyFn);