When compiling with `-O3` clang versions >= 5.0 may
generate code containing auxiliary operations dividing
by zero altough the result is not used. Specifically code like this

```cpp
for (int i=0; i<=3; i++)
  for (int j=0; j<=3; j++)
    for (int k=0; k<=3; k++)
      if ((m!=i) && (m!=j) && (m!=k))
        z += x*(1.0/(m-k))*(1.0/(m-j))*(1.0/(m-i));
```

should never devide by zero. While the result of the code
is correct with clang, it seems to produce additional
operations for the ruled out cases where we would devide by zero.
For more details see the clang bug: https://bugs.llvm.org/show_bug.cgi?id=40280

The only possible solution on our side is to turn of FP exceptions
for clang.