/in/foo.cc: In member function 'int Date::de(Date&)':
/in/foo.cc:45:18: warning: statement has no effect [-Wunused-value]
             for (m; m < obj.m; m++)
                  ^
/in/foo.cc:47:18: warning: statement has no effect [-Wunused-value]
             for (y; y <= obj.y; y++)
                  ^
/in/foo.cc:56:18: warning: statement has no effect [-Wunused-value]
             for (y; y < obj.y-1; y++)
                  ^
/in/foo.cc: In member function 'int Date::isleap()':
/in/foo.cc:29:5: warning: control reaches end of non-void function [-Wreturn-type]
     }
     ^