how to solve "ruby installation is missing psych" error?

ruby-on-rails ruby macos rvm

102,599

Solution 1

In my case

rvm pkg install libyaml

and

rvm reinstall ruby-1.9.3-p125

solved the problem.

For people using Ubuntu, make sure that libtool is installed prior to the steps above:

sudo apt-get install libtool

For macOS users (with homebrew):

rm -rf /usr/local/lib/ruby/gems/ && brew reinstall ruby

Solution 2

If not using rvm, but rather you are building and installing ruby 1.9.3 from scratch — for example, you're managing your ruby versions with rbenv — you must install libyaml first. Get it from http://pyyaml.org/; at the moment, the file you want is http://pyyaml.org/download/libyaml/yaml-0.1.4.tar.gz. Open the tarball and cd into the resulting folder. Then:

./configure --prefix=/usr/local
make
sudo make install

You are now ready to build ruby. Download ruby from http://ftp.ruby-lang.org/pub/ruby/. Open the tarball and cd into the resulting folder. Now:

./configure --prefix=/wherever/you/want/it/to/go
make
make install

(Or possibly sudo make install, depending on where you're putting it.) If using rbenv, you'll know it has worked if you switch to rbenv global 1.9.3-p194 (or whatever your version is called) and gem --version works without a warning. That worked for me on Mac OS X 10.6.8. (Update: I just tried this on Mac OS X 10.8.1 and it seems to have worked fine there too.)

Solution 3

for ubuntu and rvm

sudo apt-get install libtool
rvm pkg install libyaml
rvm reinstall 1.9.3

worked

Solution 4

brew install libyaml
rvm reinstall 1.9.3

Is what worked for me (on Snow Leopard).

Solution 5

In my case the solution was to add the psych gem to the Gemfile.

View more solutions

102,599

Pouya

Updated on November 18, 2020

Comments

Pouya over 3 years
I used rvm to install ruby 1.9.3. even though it was successfully installed, it complained about libyaml. and now every time i wanna install a gem (say rails) this warning shows up:
```
It seems your ruby installation is missing psych (for YAML output). To eliminate this warning, please install libyaml and reinstall your ruby.
```
I use Mac os X 10.7 (Lion).
- sailor over 12 years
  
  Have you tried to install libyaml following these instructions: pyyaml.org/wiki/LibYAML ?
- Stoutie over 10 years
  
  Are you using homebrew? Try brew doctor. Does it list a problem with libyaml link?
- Travis Clarke about 7 years
  
  Mac users: rm -rf /usr/local/lib/ruby/gems/ && brew reinstall ruby as stated in the official homebrew-core Gtihub resolved issue
johncblandii about 12 years

You actually mean: rvm package install libyaml
jordanpg about 12 years

No, he meant rvm pkg install libyaml. From rvm usage: pkg :: Install a dependency package {readline,iconv,zlib,openssl}.
Vanuan almost 12 years

I think it depends on what version of rvm you use. In rvm 1.6.9 it is package.
Paul over 11 years

No package libtool available. Nothing to do.
Paul over 11 years

didn't help for job in Jenkins.
phil88530 over 11 years

centos can't yum install libtool? not believe it.. are u using non-redhat based system and need to apt-get?
Haralan Dobrev over 11 years

After running rvm pkg install libyaml it recommends to reinstall all rubies with rvm reinstall all --force. It might be useful if you have more than one.
Sunil Gowda over 11 years

I had to 'rvm uninstall all' before installing libyaml. That's the only way the error cleared
Cristopher Van Paul over 11 years

@phil88530 old version of CentOS can be more stupid than you think
phil88530 over 11 years

@DennisCheung oh ok, never played with an old one
Martin Josefsson over 11 years

Should you use ruby-head or explicity write the version number?
Leahcim over 11 years

what should gem --version output? I installed Ruby 1.9.3-p327 but gem --version outputs 1.8.23 (not sure if that's related) and when I do bundle update, it strangely says that some gems are requiring => 1.9.2 stackoverflow.com/questions/14116083/…
matt over 11 years

your gem --version sounds correct, but maybe you've got your path munged because of former use of rvm
victorv over 11 years

I've confirmed this patch is not needed if you are using the latest stable rvm version 1.18.4
Dejan over 11 years

You might have to do sudo rvm pkg install libyaml if you get errors such as Error running 'tar xmzf /Users/Kieran/.rvm/archives/yaml-0.1.4.tar.gz -C /Users/Kieran/.rvm/src ', please read /Users/Kieran/.rvm/log/yaml/extract.log. This is because for some reason it doesn't have permissions to remove folders and replace them.
stringo0 over 11 years

I had to do this as well. rvm pkg install libyaml didn't do it for me.
Chadwick about 11 years

And if you must install yaml without sudo, specify a prefix other than /usr/local when configuring yaml, then configure ruby with --with-opt-dir=/path/to/yaml/prefix --with-yaml --prefix=/path/to/ruby/prefix
pcv about 11 years

Had to do rvm reinstall 1.9.3 --with-libyaml-dir=/home/rails/.rvm/usr as suggested in serverfault.com/questions/442150/…
user1678401 almost 11 years

You don't need libyaml: you need libyaml-dev, which is what rvm installs for you with --autolibs
Stoutie over 10 years

Resolving all brew doctor issues fixed it for me. I got an error very similar to the questioner's error while trying to gem install jekyll. All commands through rvm were giving errors too. The underlying and not so obvious problem is that homebrew, I'm assuming the means by which rvm installs stuff, was having issues. I had recently upgraded to Mavericks on Mac OS. In my case, resolving all the brew doctor issues eliminated every single error message. Now everything is working smoothly.
Stoutie over 10 years

Sometimes a question deserves a question, not an assumptive answer, to get at the root problem. In my case, I got a very similar error when doing gem install jekyll. My rvm commands were also giving me errors. I had recently upgraded to Mavericks. I think that broke some of the brew links, including libyaml. I did also reinstall rvm and ruby as well, but I'm not convinced that was an essential part of the solution. I believe resolving all the brew doctor issues, especially the brew link --overwrite libyaml fixed it for me.
Peter Degen-Portnoy about 10 years

I know this is over a year old, but the question was about an error with RVM. How could starting with "If not using rvm" be appropiate?
twinturbotom almost 10 years

rvm dpkg depricated. Use rvm autolibs
zishe almost 10 years

This question about os x.
Fu Xu over 9 years

thx :) but rvm pkg was deprecated, rvm autolibs was recommended :)
marcovtwout over 8 years

Also confirmed on Centos 5.6
Sandeep Ahuja about 8 years

Thanks @user33302. Above solution also worked for me on Mac OS EI CAPITON.
mrudult over 7 years

I instead allowed rvm to handle everything and did rvm requirements. That solved the problem.
orome over 6 years

But gem list is what causes the error in the first place (for me).
mljrg over 6 years

I am on macOS Sierra, and this worked for me. It is the same solution reported in this GitHub issue here Try this solution first as it is much simpler and less drastic than the others in this page.
Tharindu Madushanka almost 3 years

For version 3.0.0 rvm reinstall ruby-3.0.0-p0