>>>>> terminate called after throwing an instance of 'std::logic_error' >>>>> what(): basic_string::_M_construct null not valid Could this be related to #871275 "libapt-pkg5.0: requires rebuild against GCC 7 and symbols/shlibs bump" which was fixed recently in apt? IIRC this started after making gcc-7 the default ... I'll look if there are new occurrences of this bug. Andreas