/in/foo.c: In function 'main':
/in/foo.c:6:17: error: 'new' undeclared (first use in this function)
    6 |                 new double();
      |                 ^~~
/in/foo.c:6:17: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:6:20: error: expected ';' before 'double'
    6 |                 new double();
      |                    ^~~~~~~
      |                    ;