diff --git a/test/perf/PerftestQueue.cpp b/test/perf/PerftestQueue.cpp
index 9c85173..7bcb69b 100644
--- a/test/perf/PerftestQueue.cpp
+++ b/test/perf/PerftestQueue.cpp
@@ -15,7 +15,8 @@ void doNotOptimizeBuffer(const char* buf, std::size_t size)
 {
   for (std::size_t i = 0; i < size; ++i)
   {
-    benchmark::DoNotOptimize(buf[i]);
+    auto buf_data = buf[i];
+    benchmark::DoNotOptimize(buf_data);
   }
 }
 
diff --git a/test/perf/PerftestSessionWriter.cpp b/test/perf/PerftestSessionWriter.cpp
index 533c935..2cc6732 100644
--- a/test/perf/PerftestSessionWriter.cpp
+++ b/test/perf/PerftestSessionWriter.cpp
@@ -18,7 +18,8 @@ void doNotOptimizeBuffer(const char* buf, std::size_t size)
 {
   for (std::size_t i = 0; i < size; ++i)
   {
-    benchmark::DoNotOptimize(buf[i]);
+    auto buf_data = buf[i];
+    benchmark::DoNotOptimize(buf_data);
   }
 }