前川です。

mingw32をインストールして、試してみましたが、ruby-debug19 をローカルでイン
ストールできませんでした。

mingw32は、D:\MinGW にインストールし、パスも通しています。
D:\Ruby192\DevKit>path
PATH=D:\ruby192\bin;D:\MinGW\bin;D:\pik・・・・・・

linecashe19でエラーとなり、以降の関連するgemファイルのインストールを実施で
きない状態です。

参考にしたページは、http://mlog5.blog20.fc2.com/blog-category-1.html　で
す。

インストール結果のエラーメッセージは、以下です。

D:\Ruby192\DevKit>gem install rdiscount-1.6.5.gem --local
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
Successfully installed rdiscount-1.6.5
1 gem installed
Installing ri documentation for rdiscount-1.6.5...
Installing RDoc documentation for rdiscount-1.6.5...

D:\Ruby192\DevKit>gem install linecache19-0.5.11.gem --local
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing linecache19-0.5.11.gem:
        ERROR: Failed to build gem native extension.

D:/Ruby192/bin/ruby.exe 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=D:/Ruby192/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
D:/Ruby192/lib/ruby/1.9.1/net/http.rb:644:in `initialize': 到達できないホス
トに対してソケット操作を実行しようとしました。
 - connect(2) (Errno::EHOSTUNREACH)
        from D:/Ruby192/lib/ruby/1.9.1/net/http.rb:644:in `open'
        from D:/Ruby192/lib/ruby/1.9.1/net/http.rb:644:in `block in
connect'
        from D:/Ruby192/lib/ruby/1.9.1/timeout.rb:44:in `timeout'
        from D:/Ruby192/lib/ruby/1.9.1/timeout.rb:87:in `timeout'
        from D:/Ruby192/lib/ruby/1.9.1/net/http.rb:644:in `connect'
        from D:/Ruby192/lib/ruby/1.9.1/net/http.rb:637:in `do_start'
        from D:/Ruby192/lib/ruby/1.9.1/net/http.rb:626:in `start'
        from D:/Ruby192/lib/ruby/1.9.1/net/http.rb:1160:in `request'
        from
D:/Ruby192/lib/ruby/gems/1.9.1/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:239:in
 `block in read'
        from
D:/Ruby192/lib/ruby/gems/1.9.1/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:286:in
 `connect'
        from
D:/Ruby192/lib/ruby/gems/1.9.1/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:234:in
 `read'
        from
D:/Ruby192/lib/ruby/gems/1.9.1/gems/ruby_core_source-0.1.4/lib/contrib/uri_ext.rb:128:in
 `download'
        from
D:/Ruby192/lib/ruby/gems/1.9.1/gems/ruby_core_source-0.1.4/lib/ruby_core_source.rb:55:in
 `block in create_m
akefile_with_core'
        from D:/Ruby192/lib/ruby/1.9.1/tempfile.rb:320:in `open'
        from
D:/Ruby192/lib/ruby/gems/1.9.1/gems/ruby_core_source-0.1.4/lib/ruby_core_source.rb:51:in
 `create_makefile_w
ith_core'
        from extconf.rb:20:in `<main>'
Requesting http://ftp.ruby-lang.org/pub/ruby/1.9/ruby-1.9.2-p136.tar.gz

Gem files will remain installed in
D:/Ruby192/lib/ruby/gems/1.9.1/gems/linecache19-0.5.11 for inspection.
Results logged to
D:/Ruby192/lib/ruby/gems/1.9.1/gems/linecache19-0.5.11/ext/trace_nums/gem_make.out

よろしくお願いします。