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 1,351 _gen/frontend/help_meta.cc 553 _gen/frontend/help_meta.h 6 _gen/frontend/id_kind.asdl_c.h 417 _gen/frontend/match.re2c.h 25,541 _gen/frontend/types.asdl_c.h 46 27,914 lines in 7 files