diff --git a/src/core/Benchmark.cpp b/src/core/Benchmark.cpp
index c8792325..3d6f96a8 100644
--- a/src/core/Benchmark.cpp
+++ b/src/core/Benchmark.cpp
@@ -137,7 +137,7 @@ float Benchmark::get_algo_perf(Algorithm::Id algo) const {
 void Benchmark::start(const BenchAlgo bench_algo) {
     // calculate number of active miner backends in m_enabled_backend_count
     m_enabled_backend_count = 0;
-    for (backend : m_controller->miner()->backends) if (backend.isEnabled(Algorithm(ba2a[bench_algo]))) ++ m_enabled_backend_count;
+    for (auto backend : m_controller->miner()->backends) if (backend.isEnabled(Algorithm(ba2a[bench_algo]))) ++ m_enabled_backend_count;
     if (m_enabled_backend_count == 0) {
         run_next_bench_algo(m_bench_algo);
         return;