title: ruby-debug install error: failed to build gem native extension
body: <p>I'm running 1.9.2 with rails 3.</p>
  
  <p>I'm using rvm.</p>
  
  <p>I did:</p>
  
  <pre><code>sudo gem install ruby-gem
  </code></pre>
  
  <p>and got:</p>
  
  <pre><code>Building native extensions.  This could take a while...
  ERROR:  Error installing ruby-debug:
      ERROR: Failed to build gem native extension.
  
  /Users/blankman/.rvm/rubies/ruby-1.9.2-head/bin/ruby extconf.rb
  Can't handle 1.9.x yet
  *** 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
      --without-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/blankman/.rvm/rubies/ruby-1.9.2-head/bin/ruby
  
  
  Gem files will remain installed in /Users/blankman/.rvm/gems/ruby-1.9.2-head/gems/linecache-0.43 for inspection.
  Results logged to /Users/blankman/.rvm/gems/ruby-1.9.2-head/gems/linecache-0.43/ext/gem_make.out
  </code></pre>
  
  <p><strong>UPDATE</strong></p>
  
  <p>Added:</p>
  
  <p>gem 'ruby-debug19'</p>
  
  <p>and when running bundle install I get:</p>
  
  <pre><code>Fetching source index for http://rubygems.org/
  Using rake (0.8.7) 
  Using abstract (1.0.0) 
  Using activesupport (3.0.0.rc2) 
  Using builder (2.1.2) 
  Using i18n (0.4.1) 
  Using activemodel (3.0.0.rc2) 
  Using erubis (2.6.6) 
  Using rack (1.2.1) 
  Using rack-mount (0.6.13) 
  Using rack-test (0.5.6) 
  Using tzinfo (0.3.23) 
  Using actionpack (3.0.0.rc2) 
  Using mime-types (1.16) 
  Using polyglot (0.3.1) 
  Using treetop (1.4.8) 
  Using mail (2.2.7) 
  Using actionmailer (3.0.0.rc2) 
  Using arel (1.0.1) 
  Using activerecord (3.0.0.rc2) 
  Using activeresource (3.0.0.rc2) 
  Using archive-tar-minitar (0.5.2) 
  Using bundler (1.0.3) 
  Using columnize (0.3.1) 
  Using ruby_core_source (0.1.4) 
  Installing linecache19 (0.5.11) with native extensions /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/rubygems/installer.rb:483:in `rescue in block in build_extensions': ERROR: Failed to build gem native extension. (Gem::Installer::ExtensionBuildError)
  
  /Users/blankman/.rvm/rubies/ruby-1.9.2-head/bin/ruby extconf.rb 
  checking for vm_core.h... no
  checking for vm_core.h... no
  *** 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
      --without-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/blankman/.rvm/rubies/ruby-1.9.2-head/bin/ruby
      --with-ruby-dir
      --without-ruby-dir
      --with-ruby-include
      --without-ruby-include=${ruby-dir}/include
      --with-ruby-lib
      --without-ruby-lib=${ruby-dir}/lib
  /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:268:in `block (2 levels) in read': Looking for http://ftp.ruby-lang.org/pub/ruby/1.9/ruby-1.9.2-p14.tar.gz and all I got was a 404! (URI::NotFoundError)
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/net/http.rb:1186:in `block in transport_request'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/net/http.rb:2334:in `reading_body'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/net/http.rb:1185:in `transport_request'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/net/http.rb:1169:in `request'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/net/http.rb:1162:in `block in request'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/net/http.rb:627:in `start'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/net/http.rb:1160:in `request'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:239:in `block in read'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:286:in `connect'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:234:in `read'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:128:in `download'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/ruby_core_source-0.1.4/lib/ruby_core_source.rb:55:in `block in create_makefile_with_core'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/tempfile.rb:320:in `open'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/ruby_core_source-0.1.4/lib/ruby_core_source.rb:51:in `create_makefile_with_core'
      from extconf.rb:20:in `&lt;main&gt;'
  Requesting http://ftp.ruby-lang.org/pub/ruby/1.9/ruby-1.9.2-p14.tar.gz
  
  
  Gem files will remain installed in /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/linecache19-0.5.11 for inspection.
  Results logged to /Users/blankman/.rvm/gems/ruby-1.9.2-head@hz/gems/linecache19-0.5.11/ext/trace_nums/gem_make.out
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/rubygems/installer.rb:486:in `block in build_extensions'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/rubygems/installer.rb:446:in `each'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/rubygems/installer.rb:446:in `build_extensions'
      from /Users/blankman/.rvm/rubies/ruby-1.9.2-head/lib/ruby/1.9.1/rubygems/installer.rb:198:in `install'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/source.rb:100:in `install'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/installer.rb:55:in `block in run'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/spec_set.rb:12:in `block in each'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/spec_set.rb:12:in `each'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/spec_set.rb:12:in `each'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/installer.rb:44:in `run'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/installer.rb:8:in `install'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/cli.rb:221:in `install'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/vendor/thor/task.rb:22:in `run'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/vendor/thor/invocation.rb:118:in `invoke_task'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/vendor/thor.rb:246:in `dispatch'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/lib/bundler/vendor/thor/base.rb:389:in `start'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/gems/bundler-1.0.3/bin/bundle:13:in `&lt;top (required)&gt;'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/bin/bundle:19:in `load'
      from /Users/blankman/.rvm/gems/ruby-1.9.2-head@global/bin/bundle:19:in `&lt;main&gt;'
  blankmans-MacBook-Pro:hz blankman$ 
  </code></pre>