dc_state_retain
dc_state_retain(dc->current_state);
dc_state_retain(dc->current_state);
dc_state_retain(old_current_state);
dc_state_retain(dc->current_state);
dc_state_retain(transition_base_context);
dc_state_retain(scratch->backup_context);
dc_state_retain(scratch->dc->current_state);
void dc_state_retain(struct dc_state *state);