[boost] bug in type_traits/is_virtual_base_of ??

Subject: [boost] bug in type_traits/is_virtual_base_of ??
From: Daniel Larimer (dlarimer_at_[hidden])
Date: 2010-02-11 01:15:43

Using boost 1_41 I found what I believe to be a bug in is_virtual_base_of.   The following code reports that A and B are both virtual base classes of C.   

#include<boost/type_traits/is_virtual_base_of.hpp>
#include <stdio.h>
struct A
{
   int base_old;
};  
struct B
{       
   int base_data;
};                                  
        
struct C : public A, public B
{   
    virtual void test(){};
    float my_data;
};
    
int main ( int argc, char** argv )
{
    printf( "is_virtual_base_of<A,C>::value: %d\n", boost::is_virtual_base_of<A,C>::value );
    printf( "is_virtual_base_of<B,C>::value: %d\n", boost::is_virtual_base_of<B,C>::value );
} 

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