Description:
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The curl_copy_handle function don't work when used with CURLOPT_PROGRESSFUNCTION

Test script:
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<?php
$ch = curl_init('http://www.php.net');
curl_setopt($ch, CURLOPT_NOPROGRESS, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_PROGRESSFUNCTION, function() { });
$ch2 = curl_copy_handle($ch);
echo curl_exec($ch);
unset($ch);
echo curl_exec($ch2);

Expected result:
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No segault

Actual result:
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Segfault