PVS-Studio warning V610 for samba

static void *_idr_find(struct idr_context *idp, int id)
{
  ....
  if (n + IDR_BITS < 31 &&
      ((id & ~(~0 << MAX_ID_SHIFT)) >> (n + IDR_BITS))) {
    return NULL;
  }
  ....
}

This suspicious code was found in samba project by PVS-Studio static code analyzer.
Warning message is:
V610 Undefined behavior. Check the shift operator '<<. The left operand '~0' is negative. idtree.c 284

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/