Ignoring redcarpet-2.3.0 because its extensions are not built.  Try: gem pristine redcarpet --version 2.3.0
Ignoring sqlite3-1.3.10 because its extensions are not built.  Try: gem pristine sqlite3 --version 1.3.10
Ignoring therubyracer-0.12.2 because its extensions are not built.  Try: gem pristine therubyracer --version 0.12.2
Ignoring therubyracer-0.11.4 because its extensions are not built.  Try: gem pristine therubyracer --version 0.11.4
Ignoring redcarpet-2.3.0 because its extensions are not built.  Try: gem pristine redcarpet --version 2.3.0
Ignoring sqlite3-1.3.10 because its extensions are not built.  Try: gem pristine sqlite3 --version 1.3.10
Ignoring therubyracer-0.12.2 because its extensions are not built.  Try: gem pristine therubyracer --version 0.12.2
Ignoring therubyracer-0.11.4 because its extensions are not built.  Try: gem pristine therubyracer --version 0.11.4
Building native extensions with: '--with-mysql-dir=/usr/local/bin/mysql'
This could take a while...
ERROR:  Error installing mysql2:
	ERROR: Failed to build gem native extension.

    /Users/ps032791/.rvm/rubies/ruby-2.2.1/bin/ruby -r ./siteconf20150408-7066-ggkiw1.rb extconf.rb --with-mysql-dir=/usr/local/bin/mysql
checking for ruby/thread.h... *** 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/ps032791/.rvm/rubies/ruby-2.2.1/bin/$(RUBY_BASE_NAME)
/Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:456:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:587:in `try_cpp'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:1060:in `block in have_header'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:911:in `block in checking_for'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:351:in `block (2 levels) in postpone'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:321:in `open'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:351:in `block in postpone'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:321:in `open'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:347:in `postpone'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:910:in `checking_for'
	from /Users/ps032791/.rvm/rubies/ruby-2.2.1/lib/ruby/2.2.0/mkmf.rb:1059:in `have_header'
	from extconf.rb:9:in `<main>'

extconf failed, exit code 1

Gem files will remain installed in /Users/ps032791/.rvm/gems/ruby-2.2.1@record/gems/mysql2-0.3.18 for inspection.
Results logged to /Users/ps032791/.rvm/gems/ruby-2.2.1@record/extensions/x86_64-darwin-14/2.2.0-static/mysql2-0.3.18/gem_make.out