Ruby gem mysql2 install error

Question

I have the Ruby version ruby 1.9.2p0 (2010-08-18) [i386-mingw32] installed in Windows7. and the gem vesion 1.3.7

When i tried to install mysql gem, it is showing Failed to build gem native extension error, why is this? my mysql version is 5.1.36(WampServer)

E:\RubyApps\test_app2>gem install mysql2
Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
        ERROR: Failed to build gem native extension.

E:/Ruby192/bin/ruby.exe extconf.rb
checking for rb_thread_blocking_region()... *** 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=E:/Ruby192/bin/ruby
E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:368:in `try_do': The complier failed to genera
te an executable file. (RuntimeError)
You have to install development tools first.
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:435:in `try_link0'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:440:in `try_link'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:552:in `try_func'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:797:in `block in have_func'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:693:in `block in checking_for'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:280:in `block (2 levels) in postp
one'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:254:in `open'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:280:in `block in postpone'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:254:in `open'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:276:in `postpone'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:692:in `checking_for'
        from E:/Ruby192/lib/ruby/1.9.1/mkmf.rb:796:in `have_func'
        from extconf.rb:9:in `<main>'


Gem files will remain installed in E:/Ruby192/lib/ruby/gems/1.9.1/gems/mysql2-0.
2.3 for inspection.
Results logged to E:/Ruby192/lib/ruby/gems/1.9.1/gems/mysql2-0.2.3/ext/mysql2/ge
m_make.out

E:\RubyApps\test_app2>

Answer 1

You can try

gem install mysql2 -v '0.0.00' -- --with-ldflags=-L/usr/local/opt/openssl/lib --with-cppflags=-I/usr/local/opt/openssl/include

Answer 2

If you are having this same problem in Linux, basically you just need to install a few libraries first. This worked for me.

> sudo apt-get install libmysql-ruby libmysqlclient-dev

> gem install mysql

source: http://heatware.net/ruby-rails/solved-installing-mysql-gem-extconf-rb-failed-error/

Answer 3

Since this keeps coming up on google as on of the top results, I should point out that this answers is from almost 2 years ago. Here is a more updated answer: How to use "mysql2" gem in Rails 3 application on Windows 7?

---

According to the developer there is a already a reported bug for it and he is working on parting mysql2 over to Windows. As of now - it's still in the works. Use the older mysql driver for now - or use sqlite for local development.

This is from the googlegroups discussion

Blockquote Hey Erwann, There's a ticket on the mysql2 issue tracker for Win32 support already at http://github.com/brianmario/mysql2/issues#issue/8 . You can follow it for progress; I'm doing my best to get things working smoothly for you guys. Hang tight! :)

Answer 4

Just for the record: The problem should be solved!

The mysql2 gem v.0.2.6 is out, having win32 support.

gem install mysql2 worked without problems now.

See: http://github.com/brianmario/mysql2/issues/issue/8#issue/8/comment/479748