c++ - Engineered bool compares equal to both true and false, why?

Question

The example bellows compiles, but the output is rather strange :

#include <iostream>
#include <cstring>

struct A
{
    int a;
    char b;
    bool c;
};

int main()
{
    A v;
    std::memset( &v, 0xff, sizeof(v) );

    std::cout << std::boolalpha << ( true == v.c ) << std::endl;
    std::cout << std::boolalpha << ( false == v.c ) << std::endl;
}

the output is :

true
true

Can someone explains why?

If it matters, I am using g++ 4.3.0

Answer 1

Found this in the C++ standard, section 3.9.1 "Fundamental types" (note the magic footnote 42):

6. Values of type bool are either true or false. 42)

42) Using a bool value in ways described by this International Standard as ‘‘undefined,’’ such as by examining the value of an uninitialized automatic variable, might cause it to behave as if it is neither true nor false.

This is not perfectly clear for me, but seems to answer the question.