diff --git a/internal/ceres/cost_function_to_functor_test.cc b/internal/ceres/cost_function_to_functor_test.cc
index eb1d635..3c9a6fe 100644
--- a/internal/ceres/cost_function_to_functor_test.cc
+++ b/internal/ceres/cost_function_to_functor_test.cc
@@ -260,7 +260,7 @@
 };
 
 // Check that AutoDiff(Functor1) == AutoDiff(CostToFunctor(AutoDiff(Functor1)))
-#define TEST_BODY(NAME)                                                        \
+#define TEST_BODY(Functor1)                                                    \
   TEST(CostFunctionToFunctor, Functor1) {                                      \
     typedef AutoDiffCostFunction<Functor1, 2, PARAMETER_BLOCK_SIZES>           \
         CostFunction1;                                                         \