/in/foo.cc: In function 'std::pair<int, int> init(double, double)':
/in/foo.cc:14:22: warning: left operand of comma operator has no effect [-Wunused-value]
     if(!b) return (0,0);
                      ^
/in/foo.cc:14:21: error: could not convert '((void)0, 0)' from 'int' to 'std::pair<int, int>'
     if(!b) return (0,0);
                   ~~^~~