安裝Rails時出現「extconf.rb failed」消息

Question

新手在這裏。我在網站上搜索了其他類似的問題，但仍無法解決問題。我已經安裝了Ruby 2.0.0和2.0.3 RubyGem，但是當我試圖安裝Rails 4.0.0我：

Building native extensions. This could take a while... 
ERROR: Error installing rails: 
    ERROR: Failed to build gem native extension. 
    /Users/yuanhunglo/.rvm/rubies/ruby-2.0.0-p0/bin/ruby extconf.rb 
*** 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/yuanhunglo/.rvm/rubies/ruby-2.0.0-p0/bin/ruby 
    --with-atomic_reference-dir 
    --without-atomic_reference-dir 
    --with-atomic_reference-include 
    --without-atomic_reference-include=${atomic_reference-dir}/include 
    --with-atomic_reference-lib 
    --without-atomic_reference-lib=${atomic_reference-dir}/ 
/Users/yuanhunglo/.rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/mkmf.rb:431:in `try_do': The compiler failed to generate an executable file. (RuntimeError) 
You have to install development tools first. 
    from /Users/yuanhunglo/.rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/mkmf.rb:516:in `try_link0' 
    from /Users/yuanhunglo/.rvm/rubies/ruby-2.0.0-p0/lib/ruby/2.0.0/mkmf.rb:814:in `try_run' 
    from extconf.rb:22:in `<main>' 


Gem files will remain installed in /Users/yuanhunglo/.rvm/gems/ruby-2.0.0-p0/gems/atomic-1.1.10 for inspection. 
Results logged to /Users/yuanhunglo/.rvm/gems/ruby-2.0.0-p0/gems/atomic-1.1.10/ext/gem_make.out 

我試圖通過

gem install rails --version 4.0.0 

我安裝Rails我不確定設置是否有問題，或者是否還需要安裝。在此先感謝您的幫助。

Answer 1

看來你使用的是OSX。

如果由於缺少編譯器（「您必須先安裝開發工具」）而無法編譯某些擴展，則會發生此錯誤。打開App Store，下載XCode，安裝完成後點擊菜單上的「XCode」，進入首選項 - >下載 - >組件，然後下載「命令行工具」。