fixup! fixup! Use an array for the position stack rather than an Erlang list

c_src/termstack.c

@@ -15,7 +15,11 @@ termstack_push(TermStack *stack, ERL_NIF_TERM term)
         size_t new_size = stack->size * 2;
 
         if (stack->elements == &stack->__default_elements[0]) {
-            stack->elements = enif_alloc(new_size * sizeof(ERL_NIF_TERM));
+            ERL_NIF_TERM *new_elements = enif_alloc(new_size * sizeof(ERL_NIF_TERM));
+
+            memcpy(new_elements, stack->elements, stack->size * sizeof(ERL_NIF_TERM));
+
+            stack->elements = new_elements;
         } else {
             stack->elements = enif_realloc(stack->elements,
                                            new_size * sizeof(ERL_NIF_TERM));

test/jiffy_06_object_tests.erl

@@ -20,6 +20,14 @@ latin1_atom_test_() ->
     Expected = <<"{\"", 195, 164, "\":\"bar\"}">>,
     ?_assertEqual(Expected, enc(#{ Key => <<"bar">> })).
 
+nested_object_segv_test_() ->
+    Obj = nested(128),
+    Enc = enc(Obj),
+    ?_assertEqual(Obj, dec(Enc)).
+
+nested(0) -> <<"bottom">>;
+nested(N) -> {[{integer_to_binary(N), nested(N - 1)}]}.
+
 gen(ok, {J, E}) ->
     gen(ok, {J, E, J});
 gen(ok, {J1, E, J2}) ->