diff -r 4f02995ce44e -r 93851c0babe4 tests/test_utils.c
--- a/tests/test_utils.c	Mon Feb 26 21:07:23 2024 +0100
+++ b/tests/test_utils.c	Mon Mar 04 08:57:26 2024 +0100
@@ -248,7 +248,9 @@
     cx_test_register(suite, test_forn);
     cx_test_register(suite, test_swap_ptr);
     cx_test_register(suite, test_szmul);
+#ifdef CX_SZMUL_BUILTIN
     cx_test_register(suite, test_szmul_impl);
+#endif
 
     return suite;
 }