php 5.6.20 发布了，该版本修复了如下 bug：
cli server:
fixed bug #69953 (support mkcalendar request method).
core:
fixed bug #71596 (segmentation fault on zts with date function (setlocale)).
curl:
fixed bug #71694 (support constant curlm_added_already).
date:
fixed bug #71635 (dateperiod::getenddate segfault).
fileinfo:
fixed bug #71527 (buffer over-write in finfo_open with malformed magic file).
mbstring:
fixed bug #71906 (addresssanitizer: negative-size-param (-1) in mbfl_strcut).
odbc:
fixed bug #47803, #69526 (executing prepared statements is succesfull only for the first two statements).
fixed bug #71860 (invalid memory write in phar on filename with \0 in name).
pdo_dblib:
fixed bug #54648 (pdo::mssql forces format of datetime fields).
phar:
fixed bug #71625 (crash in php7.dll with bad phar filename).
fixed bug #71504 (parsing of tar file with duplicate filenames causes memory leak).
snmp:
fixed bug #71704 (php_snmp_error() format string vulnerability).
standard:
fixed bug #71798 (integer overflow in php_raw_url_encode).