/in/foo.c: In function 'main':
/in/foo.c:8:2: warning: implicit declaration of function 'GetArray' [-Wimplicit-function-declaration]
  GetArray(n);
  ^~~~~~~~
/in/foo.c: At top level:
/in/foo.c:11:6: warning: conflicting types for 'GetArray'
 void GetArray(int n) {
      ^~~~~~~~
/in/foo.c:8:2: note: previous implicit declaration of 'GetArray' was here
  GetArray(n);
  ^~~~~~~~