Control: retitle -1 ppl: FTBFS with swi-prolog 7.x Since it built in 'stretch/testing' successfully I looked at the difference in installed packages after satisfying the build dependencies ... the only interesting package with a newer upstream version in sid seemed to be swi-prolog ... and then rebuilt it again in 'sid/unstable' but with swi-prolog 6.x from 'testing', which worked well. Andreas