void CLASS canon_600_fixed_wb (int temp)
{
  static const short mul[4][5] = {
    {  667, 358,397,565,452 },
    {  731, 390,367,499,517 },
    { 1119, 396,348,448,537 },
    { 1399, 485,431,508,688 } };
  int lo, hi, i;
  float frac=0;

  for (lo=4; --lo; )
    if (*mul[lo] <= temp) break;
  for (hi=0; hi < 3; hi++)
    if (*mul[hi] >= temp) break;
  if (lo != hi)
    frac = (float) (temp - *mul[lo]) / (*mul[hi] - *mul[lo]);
  for (i=1; i < 5; i++)
    pre_mul[i-1] = 1 / (frac * mul[hi][i] + (1-frac) * mul[lo][i]);
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.