安装pecl_http:raphf安装,但./configure没有看到它

我试图安装pecl_http作为php的扩展。

phpise工作正常,因为我得到configuration文件了。 当我去键入./configure时,我得到以下错误信息;

... checking openssl/crypto.h usability... yes checking openssl/crypto.h presence... yes checking for openssl/crypto.h... yes checking for gnutls support in libcurl... no checking for ares support in libcurl... no checking for bundled SSL CA info... /etc/ssl/certs/ca-certificates.crt checking for event2/event.h... found in /usr checking for libevent version, roughly... 2.0.19-stable checking for ext/raphf support... no configure: error: Please install pecl/raphf and activate extension=raphf.so in your php.ini 

我已经添加了以下行到我的php.ini文件

 extension=raphf.so 

我知道raphf是安装和加载,因为我已经检查了以下的PHP

 echo extension_loaded(raphf) ? "raphf loaded" : "raphf not loaded"; 

它回来了它被加载。

为什么./configure不能看到raphf?