diff --git a/tests/test_stl_io.c b/tests/test_stl_io.c
index 3e4d024..5fc34c4 100644
--- a/tests/test_stl_io.c
+++ b/tests/test_stl_io.c
@@ -31,8 +31,8 @@ typedef struct stl_testcase_result stl_testcase_result_t;
 void ascii_begin_solid(
         void* cookie, size_t stream_size, const char* solid_name)
 {
-    GMIO_UNUSED(stream_size);
     stl_testcase_result_t* res = (stl_testcase_result_t*)cookie;
+    GMIO_UNUSED(stream_size);
     if (res != NULL) {
         res->solid_name[0] = 0;
         if (solid_name != NULL)