bundle install / Error in Installing libv8 (3.3.10.4) on rails (running on Lion)

Question

I have added the gem 'sunspot_rails' in my gem file and ran bundle install. I have been getting errors in installing libv8 and the error message is as follows:

Installing libv8 (3.3.10.4) with native extensions 
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

        /opt/local/bin/ruby extconf.rb 
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
    --with-opt-dir
    --with-opt-include
    --without-opt-include=${opt-dir}/include
    --with-opt-lib
    --without-opt-lib=${opt-dir}/lib
    --with-make-prog
    --without-make-prog
    --srcdir=.
    --curdir
    --ruby=/opt/local/bin/ruby
extconf.rb:13: uninitialized constant Gem (NameError)
Checking for Python...

Gem files will remain installed in /Users/sonyakim/.rvm/gems/ruby-1.9.2-p290/gems/libv8-3.3.10.4 for inspection.
Results logged to /Users/sonyakim/.rvm/gems/ruby-1.9.2-p290/gems/libv8-3.3.10.4/ext/libv8/gem_make.out
An error occured while installing libv8 (3.3.10.4), and Bundler cannot continue.
Make sure that `gem install libv8 -v '3.3.10.4'` succeeds before bundling.

When I run gem install libv8 -v '3.3.10.4', the following error message is printed:

Building native extensions.  This could take a while...
ERROR:  Error installing libv8:
    ERROR: Failed to build gem native extension.

        /opt/local/bin/ruby extconf.rb
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
    --with-opt-dir
    --with-opt-include
    --without-opt-include=${opt-dir}/include
    --with-opt-lib
    --without-opt-lib=${opt-dir}/lib
    --with-make-prog
    --without-make-prog
    --srcdir=.
    --curdir
    --ruby=/opt/local/bin/ruby
extconf.rb:13: uninitialized constant Gem (NameError)
Checking for Python...

Gem files will remain installed in /Users/sonyakim/.rvm/gems/ruby-1.9.2-p290/gems/libv8-3.3.10.4 for inspection.
Results logged to /Users/sonyakim/.rvm/gems/ruby-1.9.2-p290/gems/libv8-3.3.10.4/ext/libv8/gem_make.out

How can I install libv8 properly?

Answer 1

Force extconf.rb file to require rubygems on install:

RUBYOPT=-rrubygems gem install libv8 -v '3.3.10.4'

Found here: https://coderwall.com/p/y1djxq