安装mysql2 gem时出错：无法构建gem本机扩展

Windows XP。 Ruby 1.9.2。安装Rails。 MySQL已安装。当我尝试运行gem install mysql2（或bundle install）我得到的错误：安装mysql2 gem时出错：无法构建gem本机扩展

C:\ruby\cred2>gem install mysql2 
Building native extensions. This could take a while... 
ERROR: Error installing mysql2: 
     ERROR: Failed to build gem native extension. 

C:/Ruby192/bin/ruby.exe extconf.rb 
checking for rb_thread_blocking_region()... *** 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:/Ruby192/bin/ruby 
C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:368:in `try_do': The complier failed to genera 
te an executable file. (RuntimeError) 
You have to install development tools first. 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:435:in `try_link0' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:440:in `try_link' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:552:in `try_func' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:797:in `block in have_func' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:693:in `block in checking_for' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:280:in `block (2 levels) in postp 
one' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:254:in `open' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:280:in `block in postpone' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:254:in `open' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:276:in `postpone' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:692:in `checking_for' 
     from C:/Ruby192/lib/ruby/1.9.1/mkmf.rb:796:in `have_func' 
     from extconf.rb:9:in `<main>' 


Gem files will remain installed in C:/Ruby192/lib/ruby/gems/1.9.1/gems/mysql2-0. 
2.4 for inspection. 
Results logged to C:/Ruby192/lib/ruby/gems/1.9.1/gems/mysql2-0.2.4/ext/mysql2/ge 
m_make.out 

C:\ruby\cred2>

来源

2010-10-14 Captain Claptrap

可能重复（http://stackoverflow.com/questions/3608287/error-installing-mysql2-failed-to-build- gem-native-extension） – 2013-06-30 22:56:18