suppress this valgrind error

suppress this valgrind error

<error>
  <unique>0x4</unique>
  <tid>1</tid>
  <kind>InvalidWrite</kind>
  <what>Invalid write of size 8</what>
  <stack>
    <frame>
      <ip>0x400A299</ip>
      <obj>/lib/x86_64-linux-gnu/ld-2.15.so</obj>
      <fn>do_lookup_x</fn>
      <dir>/build/buildd/eglibc-2.15/elf</dir>
      <file>dl-lookup.c</file>
      <line>250</line>
    </frame>
    <frame>
      <ip>0x403122F</ip>
    </frame>
    <frame>
      <ip>0x400A522</ip>
      <obj>/lib/x86_64-linux-gnu/ld-2.15.so</obj>
      <fn>_dl_lookup_symbol_x</fn>
      <dir>/build/buildd/eglibc-2.15/elf</dir>
      <file>dl-lookup.c</file>
      <line>739</line>
    </frame>
  </stack>
  <auxwhat>Address 0x7feffeec8 is on thread 1's stack</auxwhat>
</error>

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