新手问题 求助 安装 rails 提示 Failed to build gem native extension
ruby 版本 2.0.0，gem 版本 2.4.8.
我在 终端 执行 gem install rails，提示 Building native extensions. This could take a while... ERROR: Error installing rails: ERROR: Failed to build gem native extension.
各位大大，这个怎么破？
我按照提示，运行了 xcode-select --install ，然后就好了。
下面是整个错误信息：
> ERROR: Error installing rails:
> ERROR: Failed to build gem native extension.
>
> /Users/qitmac000340/.rvm/rubies/ruby-2.0.0-p643/bin/ruby -r ./siteconf20150818-39064-b7so5m.rb extconf.rb
>checking if the C compiler accepts ... yes
>checking if the C compiler accepts -Wno-error=unused-command-line-argument-hard-error-in-future... no
>Building nokogiri using packaged libraries.
>-----
>The file "/usr/include/iconv.h" is missing in your build environment,
>which means you haven't installed Xcode Command Line Tools properly.
>
>To install Command Line Tools, try running `xcode-select --install` on
>terminal and follow the instructions. If it fails, open Xcode.app,
>select from the menu "Xcode" - "Open Developer Tool" - "More Developer
>Tools" to open the developer site, download the installer for your OS
>version and run it.
>-----
>*** 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/qitmac000340/.rvm/rubies/ruby-2.0.0-p643/bin/ruby
> --help
> --clean
> --use-system-libraries
> --enable-static
> --disable-static
> --with-zlib-dir
> --without-zlib-dir
> --with-zlib-include
> --without-zlib-include=${zlib-dir}/include
> --with-zlib-lib
> --without-zlib-lib=${zlib-dir}/lib
> --enable-cross-build
> --disable-cross-build
>
>extconf failed, exit code 1
>
>Gem files will remain installed in /Users/qitmac000340/.rvm/gems/ruby-2.0.0-p643/gems/nokogiri-1.6.6.2 for inspection.
>Results logged to /Users/qitmac000340/.rvm/gems/ruby-2.0.0-p643/extensions/x86_64-darwin-14/2.0.0/nokogiri->1.6.6.2/gem_make.out
