C++ vector strange behaviour
<p>Consider this program:</p>

<pre><code>#include &lt;iostream&gt;
#include &lt;vector&gt;

using namespace std;

int main(void)
{
    vector&lt;double&gt; a;
    while (a.size() &lt;= 10)
        a.push_back(2);
    cout &lt;&lt; a[15] &lt;&lt; endl;
}
</code></pre>

<p>I would expect it to crash when asked to access 15-th element of a, but it does not (outputs 0 on my system).  What gives?  Is this some new feature in gcc or something?</p>
