I just tried to build it on ppc64el and it fails with the same mistake. The patch attached solves this problem.
- Bug#804736: libwfut: FTBFS: sigc++/object_slot.h: No such fi... Olek Wojnar
- Bug#804736: libwfut: FTBFS: sigc++/object_slot.h: No su... Breno Leitao
- Bug#804736: libwfut: FTBFS: sigc++/object_slot.h: N... James Cowgill
- Bug#804736: libwfut: FTBFS: sigc++/object_slot.... Breno Leitao
