title: Error installing json on windows 8.1
body: <p>I have installed <code>rails 4.2.3</code> and <code>ruby 2.2.2p95</code> on <code>windows 8.1 x64</code> . When I try to run "bundle install" the installation fails because of <code>json -v 1.8.3</code>. I already have <code>json version 1.8.1</code> installed. When I run rubygems update command it does not get updated. If I try to individually run <code>gem install json -v 1.8.3</code> or <code>gem install json --platform=ruby --version=1.8.3</code> I get the following error.</p>
  
  <pre><code>ERROR:  While executing gem ... (OptionParser::InvalidArgument)
  invalid argument: -platform=ruby
  
  C:\&gt;gem install json --platform=ruby --version=1.8.3
  Building native extensions.  This could take a while...
  ERROR:  Error installing json:
      ERROR: Failed to build gem native extension.
  
  C:/Ruby22-x64/bin/ruby.exe -r ./siteconf20150719-4308-1m86usl.rb extconf.rb
  creating Makefile
  
  make "DESTDIR=" clean
  
  make "DESTDIR="
  generating generator-x64-mingw32.def
  compiling generator.c
  make: x86_64-w64-mingw32-gcc: Command not found
  make: *** [generator.o] Error 127
  
  make failed, exit code 2
  
  Gem files will remain installed in C:/Ruby22-        x64/lib/ruby/gems/2.2.0/gems/json-1
  .8.3 for inspection.
  Results logged to C:/Ruby22-x64/lib/ruby/gems/2.2.0/extensions/x64-mingw32/2.2.0
  /json-1.8.3/gem_make.out
  </code></pre>