diff --git a/cpp/benchmarks/common/generate_nullmask.cu b/cpp/benchmarks/common/generate_nullmask.cu
index 5b343c47e80..502af95a971 100644
--- a/cpp/benchmarks/common/generate_nullmask.cu
+++ b/cpp/benchmarks/common/generate_nullmask.cu
@@ -29,12 +29,8 @@ struct bool_generator {
   thrust::minstd_rand engine;
   thrust::uniform_real_distribution<float> dist;
   float probability_true;
-  bool_generator(thrust::minstd_rand engine, float probability_true)
-    : engine(engine), dist{0, 1}, probability_true{probability_true}
-  {
-  }
-  bool_generator(unsigned seed, float valid_probability)
-    : engine(seed), dist{0, 1}, probability_true{valid_probability}
+  bool_generator(unsigned seed, float probability_true)
+    : engine(seed), dist{0, 1}, probability_true{probability_true}
   {
   }