sass compile error - StalenessChecker::Mutex (NameError)

Question

Any ideas on this error - the sass compilejust fails - have tried gem update --system and gem update and remove and reinstall sass gem

sudo sass --update --trace styles.scss overwrite styles.css
Password:
/Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/../lib/sass/../sass/plugin/staleness_checker.rb:27: uninitialized constant Sass::Plugin::StalenessChecker::Mutex (NameError)
    from /Library/Ruby/Site/1.8/rubygems/core_ext/kernel_require.rb:53:in `gem_original_require'
    from /Library/Ruby/Site/1.8/rubygems/core_ext/kernel_require.rb:53:in `require'
    from /Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/../lib/sass/../sass/plugin/compiler.rb:7
    from /Library/Ruby/Site/1.8/rubygems/core_ext/kernel_require.rb:53:in `gem_original_require'
    from /Library/Ruby/Site/1.8/rubygems/core_ext/kernel_require.rb:53:in `require'
    from /Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/../lib/sass/../sass/plugin.rb:4
    from /Library/Ruby/Site/1.8/rubygems/core_ext/kernel_require.rb:53:in `gem_original_require'
    from /Library/Ruby/Site/1.8/rubygems/core_ext/kernel_require.rb:53:in `require'
    from /Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/../lib/sass/../sass/exec.rb:381:in `watch_or_update'
    from /Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/../lib/sass/../sass/exec.rb:326:in `process_result'
    from /Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/../lib/sass/../sass/exec.rb:41:in `parse'
    from /Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/../lib/sass/../sass/exec.rb:21:in `parse!'
    from /Library/Ruby/Gems/1.8/gems/sass-3.2.11/bin/sass:9
    from /usr/bin/sass:23:in `load'
    from /usr/bin/sass:23

Answer 1

This same issue started popping up for me today. I suppose there is something wrong with sass-3.2.11 or some configuration that I am not aware of.

To get past the issue for now I uninstalled the new version and installed an older version like so:

Uninstall sass

gem uninstall sass

Install version 3.2.10

gem install sass --version 3.2.10

Reinstall compass

gem install compass

Answer 2

This has been fixed in sass 3.2.12.

Sass Issue Queue

So all you need to do is update your sass gem

gem install sass

Should pull the latest version 3.2.12 or greater