centos6.5安装php sqlsrv拓展遇到的坑

首先要升级gcc库，之后安装直接sqlsrv拓展时，会提示缺少glibc2.14，此时坑就开始了。（低版本的gcc库会一直存在，需要删除软连接https://blog.youkuaiyun.com/lhh1113/article/details/64441802）

如果直接安装glibc2.14库，就等着哭吧，妥妥的安装不上。各种欲哭无泪。。。。。

见https://www.v2ex.com/t/481867，没办法，只能试着安装glinc2.17，（安装详见https://vissssa.gitbook.io/mysoul/env/sheng-ji-glibc-dao-2.17）

wget http://copr-be.cloud.fedoraproject.org/results/mosquito/myrepo-el6/epel-6-x86_64/glibc-2.17-55.fc20/glibc-2.17-55.el6.x86_64.rpm
wget http://copr-be.cloud.fedoraproject.org/results/mosquito/myrepo-el6/epel-6-x86_64/glibc-2.17-55.fc20/glibc-common-2.17-55.el6.x86_64.rpm
wget http://copr-be.cloud.fedoraproject.org/results/mosquito/myrepo-el6/epel-6-x86_64/glibc-2.17-55.fc20/glibc-devel-2.17-55.el6.x86_64.rpm
wget http://copr-be.cloud.fedoraproject.org/results/mosquito/myrepo-el6/epel-6-x86_64/glibc-2.17-55.fc20/glibc-headers-2.17-55.el6.x86_64.rpm

sudo rpm -Uvh glibc-2.17-55.el6.x86_64.rpm \
glibc-common-2.17-55.el6.x86_64.rpm \
glibc-devel-2.17-55.el6.x86_64.rpm \
glibc-headers-2.17-55.el6.x86_64.rpm

安装好之后，继续安装编译pdo——sqlsrv拓展，然而还是报错

NOTICE: PHP message: PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/pdo_sqlsrv.so' - /usr/lib64/php/modules/pdo_sqlsrv.so: undefined symbol: php_pdo_register_driver in Unknown on line

pdo_sqlsrv 安装详见https://www.jianshu.com/p/5f6af4f71672（依然有坑，sqlsrv扩展能正常安装,pdo_sqlsrv确有问题，）

pecl安装后报错

unrecognized command line option “-std=c++11”

，发现系统中存在多个版本的gcc导致这一问题，https://blog.youkuaiyun.com/lhh1113/article/details/64441802

多次尝试，终于发现（http://code.liboliu.com/?p=361）

带有pdo_*相关的扩展，是依赖pdo.so的,所以必须在引入pdo.so之后才能引入

重启php-fpm之后，发现果然装上pdo_sqlsrv扩展了