diff --git a/include/boost/random/mersenne_twister.hpp b/include/boost/random/mersenne_twister.hpp
index 5fefb28..dfdc2d7 100644
--- a/include/boost/random/mersenne_twister.hpp
+++ b/include/boost/random/mersenne_twister.hpp
@@ -434,10 +434,7 @@ private:
         // already know what they are.
         for(std::size_t j = 0; j < num_bits; ++j) {
             if(tmp.i >= n) tmp.twist();
-            if(j == num_bits - 1)
-                assert((tmp.x[tmp.i] & 1) == 1);
-            else
-                assert((tmp.x[tmp.i] & 1) == 0);
+            assert((tmp.x[tmp.i] & 1) == (j == num_bits - 1));
             ++tmp.i;
         }
         detail::polynomial phi;