Description:
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A common oversight if migrating from a normal cURL interface to multi-curl is leaving in a curl_close() command. This causes a PHP seg fault if performed after curl_multi_remove_handle. The problem was not reproducible all the time - one key to it being reproduced was having
a. Multiple cURL handles
b. Closing the first $mh using curl_multi_close; then followed by a new curl_multi_init.

This may be fixed in the CVS (re #33222 - a similar but not identical problem with the function) - I am not sure.

Reproduce code:
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$mh = curl_multi_init();

... curl_multi_exec etc.

curl_multi_remove_handle($mh,$ch);

// seg fault here:
curl_close($ch);


Expected result:
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Should give a graceful error, not a seg fault.

Actual result:
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seg fault