diff --git a/benchmarks/semaphore_benchmark.cpp b/benchmarks/semaphore_benchmark.cpp
index a4aa7bb..ba89137 100644
--- a/benchmarks/semaphore_benchmark.cpp
+++ b/benchmarks/semaphore_benchmark.cpp
@@ -75,7 +75,7 @@
   while ((BM_semaphore_sem_post_running > 0) && !sem_wait(semaphore)) {
   }
   BM_semaphore_sem_post_running = -1;
-  return NULL;
+  return nullptr;
 }
 
 class SemaphoreFixture : public benchmark::Fixture {