Gem installer error when setting up ruby on rails (Windows 7) - ruby-on-rails

Question

I'm getting an error trying to set up a Ruby on Rails site. I've never used Ruby before, so everything is clean out of the installer.
I've installed Ruby 1.9.3 and RubyGems 2.0.3. I then installed rails using gem and created a blank site with rails new. At some point I also installed the DevKit as instructed here - I can't remember when exactly, but I was explicitly asked to at some point. I then tried to start it using rails server, but it's asking me to use bundle install to install some missing gems. Easy enough, but when I try that I get the following output:
Fetching gem metadata from https://rubygems.org/...........
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.0.4)
Using i18n (0.6.1)
Using multi_json (1.7.3)
Using activesupport (3.2.13)
Using builder (3.0.4)
Using activemodel (3.2.13)
Using erubis (2.7.0)
Using journey (1.0.4)
Using rack (1.4.5)
Using rack-cache (1.2)
Using rack-test (0.6.2)
Using hike (1.2.2)
Using tilt (1.4.1)
Using sprockets (2.2.2)
Using actionpack (3.2.13)
Using mime-types (1.23)
Using polyglot (0.3.3)
Using treetop (1.4.12)
Using mail (2.5.3)
Using actionmailer (3.2.13)
Using arel (3.0.2)
Using tzinfo (0.3.37)
Using activerecord (3.2.13)
Using activeresource (3.2.13)
Using bundler (1.3.5)
Using coffee-script-source (1.6.2)
Using execjs (1.4.0)
Using coffee-script (2.2.0)
Using rack-ssl (1.3.3)
Installing json (1.7.7)
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.
"C:/Ruby/Ruby 1.9.3/bin/ruby.exe" extconf.rb
C:/Ruby/Ruby 1.9.3/bin/ruby.exe: invalid option -1 (-h will show valid options) (RuntimeError)
Gem files will remain installed in C:/Ruby/Ruby 1.9.3/lib/ruby/gems/1.9.1/gems/json-1.7.7 for inspection.
Results logged to C:/Ruby/Ruby 1.9.3/lib/ruby/gems/1.9.1/gems/json-1.7.7/ext/json/ext/generator/gem_make.out
An error occurred while installing json (1.7.7), and Bundler cannot continue.
Make sure that `gem install json -v '1.7.7'` succeeds before bundling.
I get the same error when running either gem install json -v '1.7.7' or just gem install json. This particular error has proved itself resistant to Googling, so I thought I'd try asking here. Any help would be appreciated!

Answer 1

Well, it turns out the problem was that the path to my Ruby install has spaces in it. This is apparently strongly disrecommended in a number of places, but the error message was unrelated enough that it took me a while to put two and two together.