reset imap_errorstack after outputting it

This happens in `imap_errors` as well, but seems to be omitted in the `shutdown` routine.

diff --git a/ext/imap/php_imap.c b/ext/imap/php_imap.c
index acde3ba6295fd2d87b0a5d42890b36858e0e2664..9a5e6e84a7188aff8c7a4b54c880d847183e174c 100644 (file)
--- a/ext/imap/php_imap.c
+++ b/ext/imap/php_imap.c
@@ -1082,6 +1082,7 @@ PHP_RSHUTDOWN_FUNCTION(imap)
                        }
                }
                mail_free_errorlist(&IMAPG(imap_errorstack));
+               IMAPG(imap_errorstack) = NIL;
        }
 
        if (IMAPG(imap_alertstack) != NIL) {