当尝试安装nokogiri时，我得到：
± gem install nokogiri -v '1.6.0'
Building native extensions. This could take a while...
/Users/Chintan/.rvm/rubies/ruby-1.9.3-p327/lib/ruby/1.9.1/rubygems/ext/builder.rb:48: warning: Insecure world writable dir /usr/local/bin in PATH, mode 040777
ERROR: Error installing nokogiri:
ERROR: Failed to build gem native extension.
/Users/Chintan/.rvm/rubies/ruby-1.9.3-p327/bin/ruby extconf.rb
/Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/mini_portile-0.5.0/lib/mini_portile.rb:199: warning: Insecure world writable dir /usr/local/bin in PATH, mode 040777
Extracting libxml2-2.8.0.tar.gz into tmp/x86_64-apple-darwin11.4.0/ports/libxml2/2.8.0... OK
Running 'configure' for libxml2 2.8.0... ERROR, review 'tmp/x86_64-apple-darwin11.4.0/ports/libxml2/2.8.0/configure.log' to see what happened.
*** 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=/Users/Chintan/.rvm/rubies/ruby-1.9.3-p327/bin/ruby
/Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/mini_portile-0.5.0/lib/mini_portile.rb:235:in `block in execute': Failed to complete configure task (RuntimeError)
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/mini_portile-0.5.0/lib/mini_portile.rb:227:in `chdir'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/mini_portile-0.5.0/lib/mini_portile.rb:227:in `execute'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/mini_portile-0.5.0/lib/mini_portile.rb:57:in `configure'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/mini_portile-0.5.0/lib/mini_portile.rb:100:in `cook'
from extconf.rb:101:in `block in <main>'
from extconf.rb:119:in `call'
from extconf.rb:119:in `block in <main>'
from extconf.rb:109:in `tap'
from extconf.rb:109:in `<main>'
Gem files will remain installed in /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/nokogiri-1.6.0 for inspection.
Results logged to /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/nokogiri-1.6.0/ext/nokogiri/gem_make.out
看起来问题出在C编译器上，以下是config.log的内容：
checking build system type... x86_64-apple-darwin12.2.1
checking host system type... x86_64-apple-darwin12.2.1
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... ./install-sh -c -d
checking for gawk... no
checking for mawk... no
checking for nawk... no
checking for awk... awk
checking whether make sets $(MAKE)... yes
checking for gcc... gcc
checking whether the C compiler works... no
configure: error: in `/Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/nokogiri-1.6.0/ext/nokogiri/tmp/x86_64-apple-darwin11.4.0/ports/libxml2/2.8.0/libxml2-2.8.0':
configure: error: C compiler cannot create executables
See `config.log' for more details
更新：重新安装我的编译器可以安装nokogiri，但我无法启动rails服务器：
/Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require': dlopen(/Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rmagick-2.13.2/lib/RMagick2.bundle, 9): Library not loaded: /usr/local/lib/libMagickCore-Q16.7.dylib (LoadError)
Referenced from: /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rmagick-2.13.2/lib/RMagick2.bundle
Reason: image not found - /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rmagick-2.13.2/lib/RMagick2.bundle
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `block in require'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:236:in `load_dependency'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rmagick-2.13.2/lib/RMagick.rb:11:in `<top (required)>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `block in require'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:236:in `load_dependency'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require'
from /Users/Chintan/Documents/Work/Aidin/config/initializers/imagemagick.rb:1:in `<top (required)>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/zeus-0.13.3/lib/zeus/load_tracking.rb:50:in `load'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/zeus-0.13.3/lib/zeus/load_tracking.rb:50:in `load'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/zeus-0.13.3/lib/zeus/load_tracking.rb:43:in `load'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:245:in `block in load'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:236:in `load_dependency'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:245:in `load'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/engine.rb:588:in `block (2 levels) in <class:Engine>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/engine.rb:587:in `each'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/engine.rb:587:in `block in <class:Engine>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/initializable.rb:30:in `instance_exec'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/initializable.rb:30:in `run'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/initializable.rb:55:in `block in run_initializers'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/initializable.rb:54:in `each'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/initializable.rb:54:in `run_initializers'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/application.rb:136:in `initialize!'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/railtie/configurable.rb:30:in `method_missing'
from /Users/Chintan/Documents/Work/Aidin/config/environment.rb:5:in `<top (required)>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `block in require'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:236:in `load_dependency'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/activesupport-3.2.13/lib/active_support/dependencies.rb:251:in `require'
from /Users/Chintan/Documents/Work/Aidin/config.ru:3:in `block in <main>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rack-1.4.5/lib/rack/builder.rb:51:in `instance_eval'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rack-1.4.5/lib/rack/builder.rb:51:in `initialize'
from /Users/Chintan/Documents/Work/Aidin/config.ru:in `new'
from /Users/Chintan/Documents/Work/Aidin/config.ru:in `<main>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rack-1.4.5/lib/rack/builder.rb:40:in `eval'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rack-1.4.5/lib/rack/builder.rb:40:in `parse_file'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rack-1.4.5/lib/rack/server.rb:200:in `app'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/commands/server.rb:46:in `app'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rack-1.4.5/lib/rack/server.rb:304:in `wrapped_app'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/rack-1.4.5/lib/rack/server.rb:254:in `start'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/commands/server.rb:70:in `start'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/commands.rb:55:in `block in <top (required)>'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/commands.rb:50:in `tap'
from /Users/Chintan/.rvm/gems/ruby-1.9.3-p327@aidin_development/gems/railties-3.2.13/lib/rails/commands.rb:50:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'
上次我遇到这个问题时，修复方法只是重新安装apple-gcc42，但现在似乎不是问题所在。有什么想法吗？
看起来这个问题已经得到解决：nokogiri不会安装-错误：无法构建gem本机扩展
尝试
sudo apt-get install libxslt-dev libxml2-dev
您需要libxslt和libxml2来构建nokogiri。由于您使用的是MacOS X，因此需要通过MacPorts或Homebrew进行安装。对于自制啤酒，请尝试：
brew install libxslt libxml2
自制软件0.9
显然，有些人在自制软件0.9下安装libiconv时遇到了问题（见问题#442）。据报道，以下是有效的：
brew install libxml2 libxslt
brew link libxml2 libxslt
然后从源安装libiconv：
wget http://ftp.gnu.org/pub/gnu/libiconv/libiconv-1.13.1.tar.gz
tar xvfz libiconv-1.13.1.tar.gz
cd libiconv-1.13.1
./configure --prefix=/usr/local/Cellar/libiconv/1.13.1
make
sudo make install
然后（最后）安装nokogiri:
gem install nokogiri -- --with-xml2-include=/usr/local/Cellar/libxml2/2.7.8/include/libxml2
--with-xml2-lib=/usr/local/Cellar/libxml2/2.7.8/lib
--with-xslt-dir=/usr/local/Cellar/libxslt/1.1.26
--with-iconv-include=/usr/local/Cellar/libiconv/1.13.1/include
--with-iconv-lib=/usr/local/Cellar/libiconv/1.13.1/lib
此解决方法对我有效：https://github.com/opscode-cookbooks/xml/issues/19
1） 添加liblzma-dev和z-lib1g-dev
sudo apt-get install liblzma-dev zlib1g-dev
2） 使用这些进行安装
sudo /opt/chef/embedded/bin/gem install nokogiri -q --no-rdoc --no-ri -v "1.6.5" -- --use-system-libraries --with-xml2-include=/usr/include/libxml2
以下操作对我有效http://jasdeep.ca/2013/10/installing-nokogiri-fails-os-x-mavericks/
这是小牛队的一个涉及开发工具的问题。
nokogiri网站上详细介绍了更全面的案例
对我来说，在MacO上，它的工作方式就像这里所建议的那样：
brew install libxml2
# If installing directly
gem install nokogiri -- --use-system-libraries
--with-xml2-include=$(brew --prefix libxml2)/include/libxml2
# If using Bundle
bundle config build.nokogiri --use-system-libraries
--with-xml2-include=$(brew --prefix libxml2)/include/libxml2
bundle install
处理此问题时，一定要使用$(brew --prefix libxml2)因为它将使用您的Homebrew安装的正确位置。