在OSX 10.9 Maverick上安装Nokogiri时出错？
我将我的OSX（狮子）升级到小牛，我无法为我的项目安装Nokogiri。
我已经安装了XCode 5.0.1，命令行工具（使用xcode-select --install ），并且已经从Homebrew安装了libxml2，我仍然遇到问题。
错误是：
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.
/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/bin/ruby extconf.rb
checking for libxml/parser.h... *** 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
--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/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/bin/ruby
--with-zlib-dir
--without-zlib-dir
--with-zlib-include
--without-zlib-include=${zlib-dir}/include
--with-zlib-lib
--without-zlib-lib=${zlib-dir}/lib
--with-iconv-dir
--without-iconv-dir
--with-iconv-include
--without-iconv-include=${iconv-dir}/include
--with-iconv-lib
--without-iconv-lib=${iconv-dir}/lib
--with-xml2-dir
--without-xml2-dir
--with-xml2-include
--without-xml2-include=${xml2-dir}/include
--with-xml2-lib
--without-xml2-lib=${xml2-dir}/lib
--with-xslt-dir
--without-xslt-dir
--with-xslt-include
--without-xslt-include=${xslt-dir}/include
--with-xslt-lib
--without-xslt-lib=${xslt-dir}/lib
--with-libxslt-config
--without-libxslt-config
--with-pkg-config
--without-pkg-config
--with-libxml-2.0-config
--without-libxml-2.0-config
--with-libiconv-config
--without-libiconv-config
/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:368:in `try_do': The complier failed to generate an executable file. (RuntimeError)
You have to install development tools first.
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:452:in `try_cpp'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:853:in `block in find_header'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:693:in `block in checking_for'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:280:in `block (2 levels) in postpone'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:254:in `open'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:280:in `block in postpone'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:254:in `open'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:276:in `postpone'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:692:in `checking_for'
from /Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib/ruby/1.9.1/mkmf.rb:852:in `find_header'
from extconf.rb:116:in `<main>'
Gem files will remain installed in /Users/ericcamalionte/Locaweb/code/dns-panel/vendor/bundle/ruby/1.9.1/gems/nokogiri-1.5.9 for inspection.
Results logged to /Users/ericcamalionte/Locaweb/code/dns-panel/vendor/bundle/ruby/1.9.1/gems/nokogiri-1.5.9/ext/nokogiri/gem_make.out
An error occured while installing nokogiri (1.5.9), and Bundler cannot continue.
Make sure that `gem install nokogiri -v '1.5.9'` succeeds before bundling.
我从Homebrew安装了libxml2，libxslt和libiconv，并设置了参数来安装Nokogiri，但是不能工作。
我无法在环境中发现什么问题，你能帮助我吗？
您也可以在Mac OS X 10.9 Mavericks上使用完整的XCode Install安装Nokogiri：
gem install nokogiri -- --with-xml2-include=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk/usr/include/libxml2
更新
对于那些使用优胜美地的人来说，以下命令将起作用：
gem install nokogiri -- --with-xml2-include=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk/usr/include/libxml2 --use-system-libraries
或者，它实际上可能在您的MacOSX10.11.sdk文件夹中（我的MacOSX10.11.sdk为2015年9月18日），所以即使您还没有完全使用El Capitan，我最近更新了XCode，您可能需要使用下面的El Capitan SDK路径：
更新
对于那些使用El Capitan的人来说，以下命令将起作用：
gem install nokogiri -- --with-xml2-include=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk/usr/include/libxml2 --use-system-libraries
更新
对于那些使用Sierra的人来说，以下命令将起作用
gem install nokogiri -- --with-xml2-include=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.12.sdk/usr/include/libxml2 --use-system-libraries
在这里导航动画GIF后，我所要做的只是简单的xcode-select --install和gem install nokogiri工作正常。
我发现这个日志，看到没有找到gcc-4.2：
package configuration for libxslt
cflags: -I/usr/local/Cellar/libxslt/1.1.28/include -I/usr/local/Cellar/libxml2/2.9.1/include/libxml2
ldflags: -L/usr/local/Cellar/libxslt/1.1.28/lib -L/usr/local/Cellar/libxml2/2.9.1/lib
libs: -lxslt -lxml2 -lz -lpthread -liconv -lm -lxml2
package configuration for libxml-2.0
cflags: -I/usr/local/Cellar/libxml2/2.9.1/include/libxml2
ldflags: -L/usr/local/Cellar/libxml2/2.9.1/lib
libs: -lxml2
package configuration for libiconv is not found
"/usr/bin/gcc-4.2 -o conftest -I/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/include/ruby-1.9.1/x86_64-darwin11.4.0 -I/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/include/ruby-1.9.1/ruby/backward -I/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/include/ruby-1.9.1 -I. -I/usr/local/Cellar/libxslt/1.1.28/include -I/usr/local/Cellar/libxml2/2.9.1/include/libxml2 -I/usr/local/Cellar/libiconv/1.14/include -I/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxml2/2.8.0/include -I/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxslt/1.1.26/include -I/Users/ericcamalionte/.rvm/usr/include -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings -Wno-missing-field-initializers -Wshorten-64-to-32 -Wno-long-long -fno-common -pipe -g -DXP_UNIX -O3 -Wall -Wcast-qual -Wwrite-strings -Wconversion -Wmissing-noreturn -Winline -DNOKOGIRI_USE_PACKAGED_LIBRARIES -DNOKOGIRI_LIBXML2_PATH='"/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxml2/2.8.0"' -DNOKOGIRI_LIBXSLT_PATH='"/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxslt/1.1.26"' -I/usr/local/Cellar/libxslt/1.1.28/include -I/usr/local/Cellar/libxml2/2.9.1/include/libxml2 -I/usr/local/Cellar/libxml2/2.9.1/include/libxml2 conftest.c -L. -L/Users/ericcamalionte/.rvm/rubies/ruby-1.9.2-p320/lib -L/usr/local/Cellar/libxslt/1.1.28/lib -L/usr/local/Cellar/libxml2/2.9.1/lib -L/usr/local/Cellar/libiconv/1.14/lib -L/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxml2/2.8.0/lib -L/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxslt/1.1.26/lib -L/Users/ericcamalionte/.rvm/usr/lib -L. -Wl,-rpath,/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxml2/2.8.0/lib -Wl,-rpath,/Users/ericcamalionte/.rvm/gems/ruby-1.9.2-p320@dns-panel/gems/nokogiri-1.6.0/ports/x86_64-apple-darwin13.0.0/libxslt/1.1.26/lib -L/usr/local/Cellar/libxslt/1.1.28/lib -L/usr/local/Cellar/libxml2/2.9.1/lib -L/usr/local/Cellar/libxml2/2.9.1/lib -lxslt -lxml2 -lz -lpthread -liconv -lm -lxml2 -lxml2 -lruby.1.9.1-static -lpthread -ldl -lobjc "
sh: /usr/bin/gcc-4.2: No such file or directory
checked program was:
/* begin */
1: #include "ruby.h"
2:
3: int main() {return 0;}
/* end */
为了解决这个问题，我使用homebrew brew install apple-gcc42并brew install apple-gcc42并为我的/ usr / bin创建了一个符号链接：
sudo ln -s /usr/local/Cellar/apple-gcc42/4.2.1-5666.3/bin/gcc-4.2 /usr/bin/gcc-4.2