#include <stdio.h>

struct A {
    A (void) {}
    virtual ~A (void) {}
    A (const A&) = delete;
    void operator= (const A&) = delete;
};

struct B : public A {
    B (const char* p) :A(),_p(p) {}
    const char* _p;
};

int main (void)
{
    B b ("hello");
    puts (b._p);
    return 0;
}

When compiling with -Weffc++ enabled, generates:

t.cc:10:8: warning: ‘struct B’ has pointer data members [-Weffc++]
 struct B : public A {
        ^
t.cc:10:8: warning:   but does not override ‘B(const B&)’ [-Weffc++]
t.cc:10:8: warning:   or ‘operator=(const B&)’ [-Weffc++]

B already has an implicitly deleted copy constructor and operator= because A implements them deleted. The compiler will correctly give a warning about it on B b2=b, for example.