mycpp generates the big file _gen/bin/oils-for-unix.mycpp.cc. Other programs like Zephyr ASDL and re2c generate other files.
_gen/_tmp/match.re2c-input.h 1,323 _gen/frontend/id_kind.asdl_c.h 412 _gen/frontend/match.re2c.h 24,784 _gen/frontend/types.asdl_c.h 46 26,565 lines in 5 files