问题
I'm running Ruby ruby 1.9.3p125 and I keep getting this error which is making it impossible for me to do any kind of development in Rails.
It seems your ruby installation is missing psych (for YAML output). To eliminate this warning, please install libyaml and reinstall your ruby.
I've Googled around and tried seemingly everything but nothing seems to be working. I'm really eager to start on some new projects but can't seem to get around this hurdle.
Any help is greatly appreciated!
回答1:
I had same problem after installing ruby 1.9.3 with rvm. I solve it by downloading yaml-0.1.4.tar.gz into ~/.rvm/archives and then reinstalled ruby again.
cd ~/.rvm/archives
wget http://pyyaml.org/download/libyaml/yaml-0.1.4.tar.gz
rvm reinstall 1.9.3
If you get some compileerrors, try with this instead
rvm reinstall 1.9.3 --with-gcc=clang
回答2:
for ubuntu 64 bit nothing was working, but finally when I installed
libyaml-dev using
sudo apt-get install libyaml-dev
everything worked even with reinstalling ruby
回答3:
The error message is a little confusing.
For Ubuntu Linux try installing
sudo apt-get install libyaml-dev
Or for openSuSE Linux run
sudo zypper install libyaml-devel
then re-compile & re-install Ruby and you should be good to go.
A couple of points, though -- run make clean to remove old compiled files. Then run sudo make install to ensure you have proper permissions for system level installs. Finally, you might get some "file 'lib' not found" errors... ignore these. Rails seems to work just fine.
回答4:
You need libyaml to be present at the time that Ruby 1.9.3 is built. See my answer here, describing the process (without rvm):
https://stackoverflow.com/a/12361446/341994
回答5:
Simple solution to this for me was brew install libyaml. In my case I got the message:
Warning: libyaml-0.1.6_1 already installed, it's just not linked
So, brew link libyaml produced
Linking /usr/local/Cellar/libyaml/0.1.6_1... 5 symlinks created
Done. This assumes you have homebrew, which you should. If you don't, install it thusly:
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
...and then start at the top here. Cheers!
来源：https://stackoverflow.com/questions/9880855/fixing-the-ruby-installation-is-missing-psych-error