==3450== Memcheck, a.k.a. Valgrind, a memory error detector for x86-linux. ==3450== Copyright (C) 2002, and GNU GPL'd, by Julian Seward. ==3450== Using valgrind-1.9.5, a program instrumentation system for x86-linux. ==3450== Copyright (C) 2000-2002, and GNU GPL'd, by Julian Seward. ==3450== Estimated CPU clock rate is 950 MHz ==3450== For more details, rerun with: -v ==3450== disInstr: unhandled opcode 0xEC then 0x88 valgrind: the `impossible' happened: unhandled x86 opcode Basic block ctr is approximately 0 sched status: Thread 1: status = Runnable, associated_mx = 0x0, associated_cv = 0x0 ==3450== at 0x80485C4: inb (in /tmp/test_ioport) ==3450== by 0x4023A6F6: __libc_start_main (../sysdeps/generic/libc-start.c:129) ==3450== by 0x8048400: (within /tmp/test_ioport) Please report this bug to: jseward@acm.org