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// Copyright (C) 2005 Free Software Foundation, Inc.
// Contributed by Nathan Sidwell 4 Apr 2005 <nathan@codesourcery.com>
// { dg-do run }
// PR 20746: Covariant return pointer could be null.
// Origin: yanliu@ca.ibm.com
// nathan@codesourcery.com
struct A {
virtual void One ();
};
struct B {
virtual B *Two ();
virtual B &Three ();
};
struct C : A, B
{
virtual C *Two ();
virtual C &Three ();
};
void A::One () {}
B *B::Two() {return this;}
B &B::Three() {return *this;}
C *C::Two () {return 0;}
C &C::Three () {return *(C *)0;}
B *Foo (B *b)
{
return b->Two ();
}
B &Bar (B *b)
{
return b->Three ();
}
int main ()
{
C c;
/* We should not adjust a null pointer. */
if (Foo (&c))
return 1;
/* But we should adjust a (bogus) null reference. */
if (!&Bar (&c))
return 2;
return 0;
}
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