Ruby Gem install Json fails on Mavericks and Xcode 5.1 - unknown argument: '-multiply_definedsuppress'

Question

I was trying run gem install json and got the following error

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    /System/Library/Framewo         


        

Answer 1

On OSX 10.10, I had several issues when running rails new firstapp such as:

ERROR:  Error installing json:
ERROR: Failed to build gem native extension.
fatal error: 'ruby/config.h' file not found

I updated rvm with this configuration and all the errors are gone!:

rvm get stable --auto-dotfiles

You can tell from the app name that I just started fiddling with Ruby on Rails, so the above advice may or may not work for you.