When trying to upgrade to Rails 3.1 on my development system I ran into an error updating the MySQL2 gem. After a bit of searching this turned out to be a known issue with win23 and the MySQL2 gem. The error I received was:
c:\>gem install mysql2
Temporarily enhancing PATH to include DevKit...
Building native extensions. This could take a while...
ERROR: Error installing mysql2:
ERROR: Failed to build gem native extension.
C:/ruby/bin/ruby.exe extconf.rb
checking for rb_thread_blocking_region()... yes
checking for main() in -llibmysql... 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=C:/ruby/bin/ruby
--with-mysql-dir
--without-mysql-dir
--with-mysql-include
--without-mysql-include=${mysql-dir}/include
--with-mysql-lib
--without-mysql-lib=${mysql-dir}/lib
--with-libmysqllib
--without-libmysqllib
Gem files will remain installed in C:/ruby/lib/ruby/gems/1.9.1/gems/mysql2-0.3.7
for inspection.
Results logged to C:/ruby/lib/ruby/gems/1.9.1/gems/mysql2-0.3.7/ext/mysql2/gem_m
ake.out
c:\>
FIRST – Be sure to install DevKit from RailsInstaller.org. It is a set of .bat and .dll files you will need to place in your the bin directory of your ruby installation. In my case my Ruby was installed at ‘c:\ruby’ so I dropped the files from DevKit in the ‘c:\ruby\bin’ directory.
Once you have DevKit installed go ahead and install an older version of the MySQL gem. I am currently using version 0.2.6 which is working just nicely with Rails 3.1.
At the command prompt run the following command:
c:\>gem install mysql2 -v 0.2.6
The MySQL2 gem should install without a problem.
c:\>gem install mysql2 -v 0.2.6 Successfully installed mysql2-0.2.6-x86-mingw32 1 gem installed Installing ri documentation for mysql2-0.2.6-x86-mingw32... Enclosing class/module 'mMysql2' for class Client not known Installing RDoc documentation for mysql2-0.2.6-x86-mingw32... Enclosing class/module 'mMysql2' for class Client not known c:\>
Now you should be all sent using Rails 3.1 and the MySQL2 gem. Just an older version. Once win32 is fully supported this work-around will no longer be necessary.
Note: There is another way to do this by specifying the library and includes. That method did not work for me however if it works for you it may be worth a shot.
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