In file included from /in/Compile/dlist_pre.cpp:2:
In file included from /in/Compile/dlist.h:78:
/in/dlist_impl.h:11:17: error: using the result of an assignment as a condition without parentheses [-Werror,-Wparentheses]
        if(this->first = NULL)
           ~~~~~~~~~~~~^~~~~~
/in/dlist_impl.h:11:17: note: place parentheses around the assignment to silence this warning
        if(this->first = NULL)
                       ^
           (                 )
/in/dlist_impl.h:11:17: note: use '==' to turn this assignment into an equality comparison
        if(this->first = NULL)
                       ^
                       ==
/in/dlist_impl.h:11:17: error: cannot assign to non-static data member within const member function 'isEmpty'
        if(this->first = NULL)
           ~~~~~~~~~~~ ^
/in/Compile/dlist_pre.cpp:12:15: note: in instantiation of member function 'Dlist<int>::isEmpty' requested here
    if(!ilist.isEmpty()) result = -1;
              ^
/in/Compile/dlist.h:18:10: note: member function 'Dlist<int>::isEmpty' is declared const here
    bool isEmpty() const;
         ^
2 errors generated.
/in/Compile/Makefile:29: recipe for target 'buildDlistPretest' failed
make: *** [buildDlistPretest] Error 1