==> ./configure --prefix=/usr/local/Cellar/php55/5.5.19 --localstatedir=/usr/local/var --sysconfdir=/usr/local/etc/php/5.5 --with-config-file-path=/usr/local/
checking for krb5-config... /usr/bin/krb5-config
checking for DSA_get_default_method in -lssl... no
checking for X509_free in -lcrypto... yes
checking for pkg-config... no
configure: error: Cannot find OpenSSL's <evp.h>
推荐 PHPBrew
sudo ln -s /Applications/Xcode6-Beta4.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include /usr/include
via: https://github.com/Homebrew/homebrew-php/issues/1181
MAMP你值得拥有
mac 一般自带php的环境，是不是冲突了
xcode-select --install
正确的结果应该是
xcode-select: error: command line tools are already installed, use "Software Update" to install updates
否则, 你就按提示安装.
安装之后就可以了.