error while installing fastthread from ruby gem . How to remove the error?

 gem install fastthread -v1.0.7
Building native extensions.  This could take a while...
ERROR:  Error installing fastthread:
    ERROR: Failed to build gem native extension.

/usr/bin/ruby1.8 extconf.rb
extconf.rb:8:in `re开发者_高级运维quire': no such file to load -- mkmf (LoadError)
    from extconf.rb:8


Gem files will remain installed in /var/lib/gems/1.8/gems/fastthread-1.0.7 for inspection.
Results logged to /var/lib/gems/1.8/gems/fastthread-1.0.7/ext/fastthread/gem_make.out

This is what I got when I tried installing from fastthread to set up SUP mail client on my system . How to get rid of this error?

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Install these and then try re-installing:

sudo apt-get install ruby1.8-dev

Try this link http://kenno.wordpress.com/2009/07/25/fixed-extconf-rb8in-require-no-such-file-to-load-mkmf-loaderror/

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I was getting this same error in OS X Lion. Having Xcode 4.3 installed doesn't cut it. You have to go to preferences in Xcode and install the command line tools, which installs the necessary compiler tools for doing native builds on the system. After I did this, then gem install fastthread worked for me.

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Just to add to this, on debian and ubuntu the "complete" ruby package is this: ruby1.8 ruby1.8-dev ri1.8 rdoc1.8 irb1.8 ruby1.8-elisp ruby1.8-examples libdbm-ruby1.8 libgdbm-ruby1.8 libtcltk-ruby1.8 libopenssl-ruby1.8 libreadline-ruby1.8

So something like

sudo aptitude install ruby1.8 ruby1.8-dev ri1.8 rdoc1.8 irb1.8 ruby1.8-elisp ruby1.8-examples libdbm-ruby1.8 libgdbm-ruby1.8 libtcltk-ruby1.8 libopenssl-ruby1.8 libreadline-ruby1.8

Will save you a lot of time when doing bundle install on a large project.