title: Error installing mysql2 gem
body: <p>I'm trying to set up my RubyOnRails development enviroment with MySQL. I have XAMPP installed, so I decided to use the XAMPP's MySQL installation, (therefore I installed the XAMPP dev package).</p>
  
  <p>Now I'm trying to install the mysql2 gem but I got this error:</p>
  
  <pre><code>gem install mysql2 --version 0.2.7 -- --with-mysql-dir=/Applications/XAMPP/xamppfiles/ --with-mysql-lib=/Applications/XAMPP/xamppfiles/lib/mysql/ –with-mysql-include=/Applications/XAMPP/xamppfiles/include/mysql/ --with-mysql-config=/Applications/XAMPP/xamppfiles/bin/mysql_config 
  Error loading RubyGems plugin "/Library/Ruby/Gems/1.8/gems/yard-0.6.3/lib/rubygems_plugin.rb": undefined method `overwrite_accessor' for Gem::Specification:Class (NoMethodError)
  Building native extensions.  This could take a while...
  ERROR:  Error installing mysql2:
      ERROR: Failed to build gem native extension.
  
    /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb --with-mysql-dir=/Applications/XAMPP/xamppfiles/ --with-mysql-lib=/Applications/XAMPP/xamppfiles/lib/mysql/ –with-mysql-include=/Applications/XAMPP/xamppfiles/include/mysql/ --with-mysql-config=/Applications/XAMPP/xamppfiles/bin/mysql_config
  checking for rb_thread_blocking_region()... no
  checking for mysql.h... yes
  checking for errmsg.h... yes
  checking for mysqld_error.h... yes
  creating Makefile
  
  make
  gcc -I. -I. -I/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/universal-darwin10.0 -I. -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H  -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -I/Applications/XAMPP/xamppfiles/include/mysql  -I/Applications/XAMPP/xamppfiles/include -L/Applications/XAMPP/xamppfiles/lib -mmacosx-version-min=10.4 -arch i386 -arch ppc   -D_P1003_1B_VISIBLE -DSIGNAL_WITH_VIO_CLOSE -DSIGNALS_DONT_BREAK_READ -DIGNORE_SIGHUP_SIGQUIT  -DDONT_DECLARE_CXA_PURE_VIRTUAL -fno-common -arch x86_64 -g -Os -pipe -fno-common -DENABLE_DTRACE  -fno-common  -pipe -fno-common  -Wall -funroll-loops  -c client.c
  gcc -I. -I. -I/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/universal-darwin10.0 -I. -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H  -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -I/Applications/XAMPP/xamppfiles/include/mysql  -I/Applications/XAMPP/xamppfiles/include -L/Applications/XAMPP/xamppfiles/lib -mmacosx-version-min=10.4 -arch i386 -arch ppc   -D_P1003_1B_VISIBLE -DSIGNAL_WITH_VIO_CLOSE -DSIGNALS_DONT_BREAK_READ -DIGNORE_SIGHUP_SIGQUIT  -DDONT_DECLARE_CXA_PURE_VIRTUAL -fno-common -arch x86_64 -g -Os -pipe -fno-common -DENABLE_DTRACE  -fno-common  -pipe -fno-common  -Wall -funroll-loops  -c mysql2_ext.c
  ./client.h:20: warning: ‘rb_thread_blocking_region’ defined but not used
  ./client.h:20: warning: ‘rb_thread_blocking_region’ defined but not used
  ./client.h:20: warning: ‘rb_thread_blocking_region’ defined but not used
  gcc -I. -I. -I/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/universal-darwin10.0 -I. -DHAVE_MYSQL_H -DHAVE_ERRMSG_H -DHAVE_MYSQLD_ERROR_H  -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -I/Applications/XAMPP/xamppfiles/include/mysql  -I/Applications/XAMPP/xamppfiles/include -L/Applications/XAMPP/xamppfiles/lib -mmacosx-version-min=10.4 -arch i386 -arch ppc   -D_P1003_1B_VISIBLE -DSIGNAL_WITH_VIO_CLOSE -DSIGNALS_DONT_BREAK_READ -DIGNORE_SIGHUP_SIGQUIT  -DDONT_DECLARE_CXA_PURE_VIRTUAL -fno-common -arch x86_64 -g -Os -pipe -fno-common -DENABLE_DTRACE  -fno-common  -pipe -fno-common  -Wall -funroll-loops  -c result.c
  cc -arch x86_64 -pipe -bundle -undefined dynamic_lookup -o mysql2.bundle client.o mysql2_ext.o result.o -L. -L/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib -L. -arch x86_64  -Wl,-rpath,/Applications/XAMPP/xamppfiles/lib    -lruby -L/Applications/XAMPP/xamppfiles/lib -I/Applications/XAMPP/xamppfiles/include -mmacosx-version-min=10.4  -L/Applications/XAMPP/xamppfiles/lib/mysql -lmysqlclient_r -lz -lm  -lpthread -ldl  
  ld: -rpath can only be used when targeting Mac OS X 10.5 or later
  collect2: ld returned 1 exit status
  make: *** [mysql2.bundle] Error 1
  
  
  Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/mysql2-0.2.7 for inspection.
  Results logged to /Library/Ruby/Gems/1.8/gems/mysql2-0.2.7/ext/mysql2/gem_make.out
  </code></pre>
  
  <p>So I think the key point here is:</p>
  
  <pre><code>ld: -rpath can only be used when targeting Mac OS X 10.5 or later
  </code></pre>
  
  <p>I've tried to set the MACOSX_DEPLOYMENT_TARGET=10.6 but nothing changes.</p>
  
  <p>By the way, I'm using Mac OS X 10.6.6, so the error above doesn't make any sense...</p>
  
  <p>Thank you!</p>