问题
When attempting to install puma "any version" on OS X El Capitan it kept failing. Thankfully, /user/dennis-best was able to shed some light and deserves all the credit for this.
回答1:
For people who are having issues with puma and openssl, particularly with Mac OS 10.11 (El Capitan), adding some flags will save you hours and hours of heartache:
gem install puma -- --with-cppflags=-I/usr/local/opt/openssl/include --with-ldflags=-L/usr/local/opt/openssl/lib
https://gist.github.com/edvinasbartkus/0e99ea8305a20737f562
回答2:
As /users/mwp mentioned you can also install OpenSSL via brew and without including the optional cppflags install puma without any hiccups. For those that don't wish to install OpenSSL via brew, the option below also works.
来源：https://stackoverflow.com/questions/33863980/problems-installing-puma-ruby-gem-on-os-x-el-capitan-10-11