Tweak mysql_config to properly install mysql2 gem with 10.8 and MySQL installed from dmg (only found solutions for Homebrew)

gem install mysql2 - fail

$ sudo gem install --no-rdoc --no-ri mysql2 --version 0.2.11 -- --with-mysql-dir=/usr/local/mysql --with-mysql-config=/usr/local/mysql/bin/mysql_config
Building native extensions.  This could take a while...
ERROR:  Error installing mysql2:
  ERROR: Failed to build gem native extension.

        /Users/hubb/.rbenv/versions/1.9.3-p0/bin/ruby extconf.rb --with-mysql-dir=/usr/local/mysql-5.6.11-osx10.7-x86_64 --with-mysql-config=/usr/local/mysql-5.6.11-osx10.7-x86_64/bin/mysql_config --with-opt-include=/usr/local/mysql-5.6.11-osx10.7-x86_64/include
checking for rb_thread_blocking_region()... yes
checking for mysql.h... no
checking for mysql/mysql.h... no
-----
mysql.h is missing.  please check your installation of mysql and try again.
-----
*** 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=${opt-dir}/include
	--with-opt-lib
	--without-opt-lib=${opt-dir}/lib
	--with-make-prog
	--without-make-prog
	--srcdir=.
	--curdir
	--ruby=/Users/hubb/.rbenv/versions/1.9.3-p0/bin/ruby
	--with-mysql-config


Gem files will remain installed in /Users/hubb/.rbenv/versions/1.9.3-p0/lib/ruby/gems/1.9.1/gems/mysql2-0.2.11 for inspection.
Results logged to /Users/hubb/.rbenv/versions/1.9.3-p0/lib/ruby/gems/1.9.1/gems/mysql2-0.2.11/ext/mysql2/gem_make.out

gem install mysql2 - win

$ sudo gem install --no-rdoc --no-ri mysql2 --version 0.2.11 -- --with-mysql-dir=/usr/local/mysql --with-mysql-config=/usr/local/mysql/bin/mysql_config
Building native extensions.  This could take a while...
Successfully installed mysql2-0.2.11
1 gem installed

mysql_config.diff

diff --git a/mysql_config b/mysql_config
index fa5cf65..853c117 100644
--- a/mysql_config
+++ b/mysql_config
@@ -116,8 +116,8 @@ libs_r=" $ldflags -L$pkglibdir -lmysqlclient_r    "
 embedded_libs=" $ldflags -L$pkglibdir -lmysqld      "
 embedded_libs="$embedded_libs "
 
-cflags="-I$pkgincludedir  -Wall -Wno-null-conversion -Wno-unused-private-field -Os -g -fno-strict-aliasing -DDBUG_OFF -arch x86_64 " #note: end space!
-cxxflags="-I$pkgincludedir  -Wall -Wno-null-conversion -Wno-unused-private-field -Os -g -fno-strict-aliasing -DDBUG_OFF -arch x86_64 " #note: end space!
+cflags="-I$pkgincludedir  -Wall -Os -g -fno-strict-aliasing -DDBUG_OFF -arch x86_64 " #note: end space!
+cxxflags="-I$pkgincludedir  -Wall -Os -g -fno-strict-aliasing -DDBUG_OFF -arch x86_64 " #note: end space!
 include="-I$pkgincludedir"
 
 # Remove some options that a client doesn't have to care about