用railsinstaller装的环境依赖的ruby rails devkit sqlite3都装过了
现在想试试mysql
C:\windows\system32>rails new E:\ruby\kk10 -d mysql

Installing mysql2 (0.3.13)
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension
.

    F:/rails/RailsInstaller/Ruby1.9.3/bin/ruby.exe extconf.rb

checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for rb_hash_dup()... yes
checking for rb_intern3()... yes
*** 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.

另：

C:\windows\system32>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.

    F:/rails/RailsInstaller/Ruby1.9.3/bin/ruby.exe extconf.rb

checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for rb_hash_dup()... yes
checking for rb_intern3()... yes
*** 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.

求大神指导
安装附带mysql路径也试过了不行。