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POIs main() really start of a C++ program?
 

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    <p>The section $3.6.1/1 from the C++ Standard reads,</p> <blockquote> <p>A program shall contain a global function called <strong>main</strong>, which is the designated <strong>start</strong> of the program.</p> </blockquote> <p>Now consider this code,</p> <pre><code>int square(int i) { return i*i; } int user_main() { for ( int i = 0 ; i &lt; 10 ; ++i ) std::cout &lt;&lt; square(i) &lt;&lt; endl; return 0; } int main_ret= user_main(); int main() { return main_ret; } </code></pre> <p>This sample code does what I intend it to do, i.e printing the square of integers from 0 to 9, <strong>before</strong> entering into the <code>main()</code> function which is supposed to be the "start" of the program.</p> <p>Have a look at the output here : <a href="http://www.ideone.com/Niy0R" rel="noreferrer">http://www.ideone.com/Niy0R</a></p> <p>I also compiled it with <code>-pedantic</code> option, GCC 4.5.0. It gives no error, not even warning!</p> <p>So my question is, </p> <p><strong>Is this code really Standard conformant?</strong></p> <p>If it's standard conformant, then does it not invalidate what the Standard says? <code>main()</code> is not start of this program! <code>user_main()</code> executed before the <code>main()</code>. </p> <p>I understand that to initialize the global variable <code>main_ret</code>, the <code>use_main()</code> executes first but that is a different thing altogether; the point is that, it <strong>does</strong> invalidate the quoted statement $3.6.1/1 from the Standard, as <code>main()</code> is NOT the <em>start</em> of the program; it is in fact the <strong>end</strong> of <em>this</em> program!</p> <hr> <p>EDIT:</p> <h2>How do you define the word 'start'?</h2> <p>It boils down to the definition of the phrase <em>"start of the program"</em>. So how exactly do you define it?</p>
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