/* Finalization: invoke the finalizer of the struct pointed to by PTR. */
static void
-struct_finalizer_trampoline (GC_PTR ptr, GC_PTR unused_data)
+struct_finalizer_trampoline (void *ptr, void *unused_data)
{
SCM obj = PTR2SCM (ptr);
scm_t_struct_finalize finalize = SCM_STRUCT_FINALIZER (obj);