The C++ Standard Technical Report 1 introduced a class template array with fixed size, that is safer than and no less efficient than a C style array.

Even if the array is much safer it is still possible to do buffer overruns as shown in this (stupid) example bellow:

#include <tr1/array>

int main()
{
    char buf[256];
    std::tr1::array<char, 128> arr;

    std::memcpy( arr.data(), buf, 129 );
}

So I implemented a self validating array with the help of a dogtag that automatically knows if the array have been compromised.
This is the same way the kernel knows if you have overstepped you stack space.

#include <thebc/array.hpp>

int main()
{
    char buf[256];
    thebc::array<char, 128> arr;

    std::memcpy( arr.data(), buf, 128 );
    arr.validate(); // no problems

    std::memcpy( arr.data(), buf, 129 );
    arr.validate(); // assertion failure
}

And if you compile with NDEBUG defined the validation is removed so there is no performance hits.