porting library to genode

[mark ll]

hi, I am trying to port a library to genode. after execute ./configuration I got config.h file which i copied  it  to libports/src/lib/mylib/my problem that in the make file of the library they generated file using  bison. the only library use some thing similar is libc so i tried to do same but i could not generate the required file 
here the part of code in my library.port file.
generated_file  += src/lib/mylib/f.c src/lib/mylib/f.c :
        bison -y -d -p src/lib/mylib/f2.y -o src/lib/mylib/f.c 

best,