GDB is gnu’s very own debugger b main or b 72 (set breakpoint on main function or line 72) r args (run with args) p thingname or p 3+5 (print a variable or return value) p/t print as binary p/x print as hex info (get args, locals) n s continue next, step, continue int test; short lsb = 0xff; test |= lsb printf("%d\n",lsb); int test;