我最近使用过datamapper，然后突然间它无法正常工作。我一直收到这个错误：
/Users/paul/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': no such file to load -- dm-mysql-adapter (LoadError)
from /Users/paul/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require'
from /Users/paul/.rvm/gems/ruby-1.9.2-p180/gems/dm-core-1.1.0/lib/dm-core/adapters.rb:163:in `load_adapter'
from /Users/paul/.rvm/gems/ruby-1.9.2-p180/gems/dm-core-1.1.0/lib/dm-core/adapters.rb:133:in `adapter_class'
from /Users/paul/.rvm/gems/ruby-1.9.2-p180/gems/dm-core-1.1.0/lib/dm-core/adapters.rb:13:in `new'
from /Users/paul/.rvm/gems/ruby-1.9.2-p180/gems/dm-core-1.1.0/lib/dm-core.rb:219:in `setup'
然后，当我尝试加载dm-mysql-adapter时，它给了我这个错误：
/Users/paul/.rvm/rubies/ruby-1.9.2-p180/bin/ruby extconf.rb --with-mysql-config=/usr/bin/mysql_config
*** 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.
我在谷歌搜索时看到类似的错误信息，但没有一个回复似乎对我有用......