$ sudo gem install mysql
Password:
Building native extensions.  This could take a while...
ERROR:  Error installing mysql:
	ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb
extconf.rb:4: warning: Insecure world writable dir /usr/local/git in PATH, mode 040777
extconf.rb:4: warning: Insecure world writable dir /usr/local/git in PATH, mode 040777
extconf.rb:7: warning: Insecure world writable dir /usr/local/git in PATH, mode 040777
extconf.rb:17: warning: Insecure world writable dir /usr/local/git in PATH, mode 040777
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lm... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lz... yes
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lsocket... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lnsl... no
checking for mysql_query() in -lmysqlclient... no
checking for main() in -lmygcc... no
checking for mysql_query() in -lmysqlclient... no


Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/mysql-2.8.1 for inspection.
Results logged to /Library/Ruby/Gems/1.8/gems/mysql-2.8.1/ext/mysql_api/gem_make.out