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

Question

I'm trying to run jekyll locally on my laptop.
I followed the guide of Github to do that, https://help.github.com/articles/using-jekyll-with-pages
Unfortunaly I'm stuck when I have typed
$bundle install
I get the following error:
Fetching gem metadata from https://rubygems.org/.........Failed to load /etc/gemrc due to permissions problem.
Resolving dependencies...
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.
/usr/bin/ruby extconf.rb
checking for main() in -lc... *** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers. Check the mkmf.log file for more details. You may
need configuration options.
Provided configuration options:
--with-opt-dir
--without-opt-dir
--with-opt-include
--without-opt-include=${opt-dir}/include
--with-opt-lib
--without-opt-lib=${opt-dir}/lib
--with-make-prog
--without-make-prog
--srcdir=.
--curdir
--ruby=/usr/bin/ruby
--with-redcloth_scan-dir
--without-redcloth_scan-dir
--with-redcloth_scan-include
--without-redcloth_scan-include=${redcloth_scan-dir}/include
--with-redcloth_scan-lib
--without-redcloth_scan-lib=${redcloth_scan-dir}/lib
--with-clib
--without-clib
/usr/lib/ruby/2.1.0/mkmf.rb:456:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
from /usr/lib/ruby/2.1.0/mkmf.rb:541:in `try_link0'
from /usr/lib/ruby/2.1.0/mkmf.rb:556:in `try_link'
from /usr/lib/ruby/2.1.0/mkmf.rb:742:in `try_func'
from /usr/lib/ruby/2.1.0/mkmf.rb:973:in `block in have_library'
from /usr/lib/ruby/2.1.0/mkmf.rb:918:in `block in checking_for'
from /usr/lib/ruby/2.1.0/mkmf.rb:351:in `block (2 levels) in postpone'
from /usr/lib/ruby/2.1.0/mkmf.rb:321:in `open'
from /usr/lib/ruby/2.1.0/mkmf.rb:351:in `block in postpone'
from /usr/lib/ruby/2.1.0/mkmf.rb:321:in `open'
from /usr/lib/ruby/2.1.0/mkmf.rb:347:in `postpone'
from /usr/lib/ruby/2.1.0/mkmf.rb:917:in `checking_for'
from /usr/lib/ruby/2.1.0/mkmf.rb:968:in `have_library'
from extconf.rb:5:in `<main>'
extconf failed, exit code 1
Gem files will remain installed in /tmp/bundler20140903-2231-pkzqqj/RedCloth-4.2.9/gems /RedCloth-4.2.9 for inspection.
Results logged to /tmp/bundler20140903-2231-pkzqqj/RedCloth-4.2.9/extensions/x86_64-linux/2.1.0/RedCloth-4.2.9/gem_make.out
An error occurred while installing RedCloth (4.2.9), and Bundler cannot
continue.
Make sure that `gem install RedCloth -v '4.2.9'` succeeds before bundling.
I tryed to install ruby multiple times but it's not solving my problem. Do you have any hints?

Answer 1

I had this problem on MacOS and it was fixed by agreeing to the Xcode License. I had recently updated Xcode and it turns out that I needed to re-agree to the license in order to use the command line tools successfully.
Just run:
xcodebuild -license

Answer 2

This worked for me:
bundle config build.nokogiri --use-system-libraries
bundle install

Answer 3

brew install qt
then
gem install RedCloth -v '4.2.9'
then
bundle install