diff --git a/benchmarks/stdio_benchmark.cpp b/benchmarks/stdio_benchmark.cpp
index 9c81e0f..21d9dc0 100644
--- a/benchmarks/stdio_benchmark.cpp
+++ b/benchmarks/stdio_benchmark.cpp
@@ -43,7 +43,7 @@
   char* buf = new char[chunk_size];
 
   if (!buffered) {
-    setvbuf(fp, 0, _IONBF, 0);
+    setvbuf(fp, nullptr, _IONBF, 0);
   }
 
   while (state.KeepRunning()) {