#include <iostream>
#include <cmath>

double log(const double x) { std::cout << "log!\n"; return x; }

int main(int argc, char *argv[])
{
  std::log(3.14);
  return 0;
}

In function 'double log(double)':
Line 4: error: declaration of 'double log(double)' throws different exceptions
compilation terminated due to -Wfatal-errors.