generate_dict includes repository_map.h which uses the optional library.
If I had to guess this gets transitively included by other
files included by generate_dict depending on your distribution's libstdc.
Original error message:
./repository_map.h:633:10: error: no template named 'optional' in namespace 'std'
generate_dict includes repository_map.h which uses the optional library. If I had to guess this gets transitively included by other files included by generate_dict depending on your distribution's libstdc.
Original error message: