64 bit code compiled for "corei7-avx" (a large printf call). ==1500== Memcheck, a memory error detector ==1500== Copyright (C) 2002-2011, and GNU GPL'd, by Julian Seward et al. ==1500== Using Valgrind-3.7.0 and LibVEX; rerun with -h for copyright info ==1500== Command: ./g_gdb -gc lim,quit ==1500== vex amd64->IR: unhandled instruction bytes: 0xC5 0xFB 0x10 0x5 0x1B 0xE8 0x1 0x0 ==1500== valgrind: Unrecognised instruction at address 0x40c1e5. gcc --version gcc (GCC) 4.7.0 20120507 (Red Hat 4.7.0-5) Copyright (C) 2012 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
AVX instruction - an upgrade to 3.8.0 will probably fix it. *** This bug has been marked as a duplicate of bug 273475 ***