Default extension location for Windows relative to php.exe

Description

Please can the default extension location be set to the ext directory in the same directory as the php.exe

It seems that the default location without an ini file loaded is
extension_dir => C:\php\ext => C:\php\ext

That would work if php was installed in C:\php

But not if its installed in C:\util\php or C:/php5.6.4 see related issue.

I know that the extension location can be specified in the php.ini,
however usage of sensible default values can prevent superflous/unnecessary configuration

首先跟踪 Windows 构建在未加载 php.ini 时如何确定 extension_dir，并使用 php.exe 作为安装参考。比较 C:\php、C:\util\php 和 C:/php5.6.4 下的安装，并验证默认值指向同级的 ext 目录而无需配置。