Re: Partial implementation in derived classes

I tried to build program with partial implementation.
However a linker generates errors.

Is there any approach that enables to use partial implementation for
similar purposes?

------ foo.cpp ---
struct Base
{
 virtual void foo1() = 0;
 virtual void foo2() = 0;
};

struct Derived1 : public Base
{
 void foo1() {}
 void foo2(); // Not for use
};

struct Derived2 : public Base
{
 void foo1(); // Not for use
 void foo2() {}
};

int main ()
{
 Base* p1 = new Derived1();
 Base* p2 = new Derived2();
 // -----------------------
 // I would like to get linkage error in the following cases:
 // p1->foo2();
 // p2->foo1();
 // -----------------------
 return 0;
}
------ foo.cpp ---

------ Compilation ------
// gpp: GNU C++ 4.0.1 (DJGPP)

$ gpp foo.cpp

c:/djgpp/tmp/cccl1W22.o:foo.cpp:(.gnu.linkonce.t._ZN8Derived1C1Ev+0x16):
undefined reference to `vtable for Derived1'
c:/djgpp/tmp/cccl1W22.o:foo.cpp:(.gnu.linkonce.t._ZN8Derived2C1Ev+0x16):
undefined reference to `vtable for Derived2' collect2: ld returned 1
exit status