问rails包安装错误therubyracer

EN

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

/Users/giowong/.rbenv/versions/2.1.3/bin/ruby extconf.rb 
checking for main() in -lpthread... yes
checking for main() in -lobjc... yes
checking for v8.h... no
*** 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
--without-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=/Users/giowong/.rbenv/versions/2.1.3/bin/ruby
--with-pthreadlib
--without-pthreadlib
--with-objclib
--without-objclib
--enable-debug
--disable-debug
--with-v8-dir
--without-v8-dir
--with-v8-include
--without-v8-include=${v8-dir}/include
--with-v8-lib
--without-v8-lib=${v8-dir}/lib
/Users/giowong/rails_project/doctible_pre_treatment/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.3/ext/libv8/location.rb:50:in `configure': You have chosen to use the version of V8 found on your system (Libv8::Location::System::NotFoundError)
and *not* the one that is bundle with the libv8 rubygem. However,
it could not be located. please make sure you have a version of   
v8 that is compatible with 3.16.14.3 installed. You may
need to special --with-v8-dir options if it is in a non-standard
location

thanks,
The Mgmt

from     /Users/giowong/rails_project/doctible_pre_treatment/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.3/lib/libv8.rb:7:in `configure_makefile'
from extconf.rb:32:in `<main>'

extconf failed, exit code 1

Gem files will remain installed in   /Users/giowong/rails_project/doctible_pre_treatment/vendor/bundle/ruby/2.1.0/gems/therubyracer-0.12.1 for inspection.
Results logged to   /Users/giowong/rails_project/doctible_pre_treatment/vendor/bundle/ruby/2.1.0/extensions/x86_64-darwin-14/2.1.0-static/therubyracer-0.12.1/gem_make.out
An error occurred while installing therubyracer (0.12.1), and Bundler cannot
continue.
Make sure that `gem install therubyracer -v '0.12.1'` succeeds before bundling.