c++ backend: fixed __open__
c++ backend: fixed __open__

pombredanne/Rusthon,kustomzone/Rusthon,tempbottle/Rusthon,rootfs/Rusthon,tempbottle/Rusthon,rusthon/Rusthon,kustomzone/Rusthon,rootfs/Rusthon,rootfs/Rusthon,kustomzone/Rusthon,secureosv/pythia,kustomzone/Rusthon,kustomzone/Rusthon,pombredanne/Rusthon,secureosv/pythia,tempbottle/Rusthon,pombredanne/Rusthon,secureosv/pythia,tempbottle/Rusthon,secureosv/pythia,pombredanne/Rusthon,rusthon/Rusthon,rootfs/Rusthon,rootfs/Rusthon,pombredanne/Rusthon,rusthon/Rusthon,rusthon/Rusthon,rusthon/Rusthon,tempbottle/Rusthon,secureosv/pythia