make l2_vm_value_type take pointer

include/lang2/vm/vm.h

 	};
 };
 
-#define l2_vm_value_type(val) ((val).flags & 0x0f)
+#define l2_vm_value_type(val) ((val)->flags & 0x0f)
 
 struct l2_vm_buffer {
 	size_t len;

lib/vm/vm.c

 	struct l2_vm_value *val = &vm->values[id];
 	val->flags |= L2_VAL_MARKED;
 
-	int typ = l2_vm_value_type(*val);
+	int typ = l2_vm_value_type(val);
 	if (typ == L2_VAL_TYPE_ARRAY) {
 		gc_mark_array(vm, val);
 	} else if (typ == L2_VAL_TYPE_NAMESPACE) {
 	struct l2_vm_value *val = &vm->values[id];
 	l2_bitset_unset(&vm->valueset, id);
 
-	int typ = l2_vm_value_type(*val);
+	int typ = l2_vm_value_type(val);
 	if (typ == L2_VAL_TYPE_ARRAY || typ == L2_VAL_TYPE_BUFFER || typ == L2_VAL_TYPE_NAMESPACE) {
 		free(val->data);
 		// Don't need to do anything more; the next round of GC will free
 }
 
 void l2_vm_free(struct l2_vm *vm) {
-	// Skip ID 0, because that should always exist
+	// Skip ID 0, because that's always NONE
 	for (size_t i = 1; i < vm->valuessize; ++i) {
 		if (!l2_bitset_get(&vm->valueset, i)) {
 			continue;

test/src/eval.t.c

 
 		l2_vm_init(&vm, (l2_word *)w.mem, w.len / sizeof(l2_word));
 		l2_vm_run(&vm);
-		assert(l2_vm_value_type(*var_lookup("foo")) == L2_VAL_TYPE_REAL);
+		assert(l2_vm_value_type(var_lookup("foo")) == L2_VAL_TYPE_REAL);
 		assert(var_lookup("foo")->real == 10);
 	}
 }