-XBT_PRIVATE void* smpi_get_tmp_sendbuffer(int size);
-XBT_PRIVATE void* smpi_get_tmp_recvbuffer(int size);
-XBT_PRIVATE void smpi_free_tmp_buffer(void* buf);
-XBT_PRIVATE void smpi_free_replay_tmp_buffers();
+XBT_PRIVATE unsigned char* smpi_get_tmp_sendbuffer(size_t size);
+XBT_PRIVATE unsigned char* smpi_get_tmp_recvbuffer(size_t size);