#define _XBT_IN_OUT(...) \
_XBT_IF_ONE_ARG(_XBT_IN_OUT_ARG1, _XBT_IN_OUT_ARGN, __VA_ARGS__)(__VA_ARGS__)
#define _XBT_IN_OUT_ARG1(fmt) \
#define _XBT_IN_OUT(...) \
_XBT_IF_ONE_ARG(_XBT_IN_OUT_ARG1, _XBT_IN_OUT_ARGN, __VA_ARGS__)(__VA_ARGS__)
#define _XBT_IN_OUT_ARG1(fmt) \