Unresolved specs during Gem::Specification.reset:

When launching Guard, I’m getting this output: $ guard WARN: Unresolved specs during Gem::Specification.reset: lumberjack (>= 1.0.2) ffi (>= 0.5.0) WARN: Clearing out unresolved specs. Please report a bug if this causes problems. What does this mean, and how do I fix it? Contents of Guardfile: guard ‘livereload’ do watch(%r{.+\.(css|js|html)$}) end guard ‘sass’, :input => … Read more