Re: Are pointers to virtual member functions unspecified?
Am 05.04.2015 um 17:56 schrieb DeMarcus:
I'm trying to understand C++11 ??5.10.
In ??5.10/1 it says "Pointers of the same type (after pointer
conversions) can be compared for equality".
This part of the wording refers to "just" pointers, such as int*. Your
example below is not related to pointers, it is related to pointers to
members.
In ??5.10/2 it says "Otherwise if either is a pointer to a virtual member
function, the result is unspecified."
This wording is relevant for pointer to members as in your example below.
Consider the following test program.
#include <cassert>
class ISomeClass
{
public:
virtual ~ISomeClass() {}
virtual void fnc() = 0;
};
int main()
{
typedef void(ISomeClass::*MemberPtr)();
MemberPtr mp = &ISomeClass::fnc;
assert( mp == &ISomeClass::fnc );
return 0;
}
Is the assert true or unspecified according to the standard?
It is unspecified, because &ISomeClass::fnc refers to a virtual member
function.
HTH & Greetings from Bremen,
Daniel Kr??gler
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