As soon as I try to use curl_setopt with CURLOPT_UPLOAD, I get a segfault, using php-cli 4.3.1.

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "http://domain/upload");
curl_setopt($ch, CURLOPT_UPLOAD, 1);
$results = curl_exec($ch);
curl_close($ch);

This is similar to bug 22681, but it happens without anything to do with fopen() as described in that bug.