/in/foo.cc:7:1: error: stray '\' in program
 \\ if(n == 0);
 ^
/in/foo.cc:7:2: error: stray '\' in program
 \\ if(n == 0);
  ^
/in/foo.cc:8:1: error: stray '\' in program
 \\  return 1;
 ^
/in/foo.cc:8:2: error: stray '\' in program
 \\  return 1;
  ^