[seL4] Rust ports on Genode/seL4

Hi, guys, I am trying to build genode/sel4 on x86_64 platform and expect to get a GUI working. And so I enable this option in my build.conf : REPOSITORIES += $(GENODE_DIR)/repos/libports. Seems that rust support is broken (because rustc version ??). Which version of rustc should I use to build rust ports on genode ? Or how can I disable rust ports in build.conf configuration or somewhere else ? thanks, -Minskey