A segmentation fault was discovered in radare2 with adf command. In libr/core/cmd_anal.c, when command "adf" has no or wrong argument, anal_fcn_data (core, input + 1) --> RAnalFunction *fcn = r_anal_get_fcn_in (core->anal, core->offset, -1); returns null pointer for fcn causing segmentation fault later in ensure_fcn_range (fcn).