C:\>gem install json --platform=ruby
Temporarily enhancing PATH to include DevKit for 2...
Building native extensions.  This could take a while...
The system cannot find the path specified.
ERROR:  Error installing json:
        ERROR: Failed to build gem native extension.

    C:/Ruby200/bin/ruby.exe extconf.rb
creating Makefile


Gem files will remain installed in C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1 for inspection.
Results logged to C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/generator/gem_make.out

C:\>gem install json --platform=ruby --verbose
HEAD https://rubygems.org/latest_specs.4.8.gz
302 Moved Temporarily
HEAD https://s3.amazonaws.com/production.s3.rubygems.org/latest_specs.4.8.gz
304 Not Modified
HEAD https://rubygems.org/specs.4.8.gz
302 Moved Temporarily
HEAD https://s3.amazonaws.com/production.s3.rubygems.org/specs.4.8.gz
304 Not Modified
Temporarily enhancing PATH to include DevKit for 2...
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/.gitignore
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/.travis.yml
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/CHANGES
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/COPYING
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/COPYING-json-jruby
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/GPL
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/Gemfile
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/README-json-jruby.markdown
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/README.rdoc
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/Rakefile
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/TODO
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/VERSION
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/data/example.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/data/index.html
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/data/prototype.js
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/diagrams/.keep
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/fbuffer/fbuffer.h
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/generator/depend
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/generator/extconf.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/generator/generator.c
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/generator/generator.h
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/parser/depend
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/parser/extconf.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/parser/parser.c
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/parser/parser.h
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/ext/json/ext/parser/parser.rl
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/install.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/ByteListTranscoder.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/Generator.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/GeneratorMethods.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/GeneratorService.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/GeneratorState.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/OptionsReader.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/Parser.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/Parser.rl
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/ParserService.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/RuntimeInfo.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/StringDecoder.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/StringEncoder.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/java/src/json/ext/Utils.java
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/json-java.gemspec
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/json.gemspec
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/json_pure.gemspec
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/bigdecimal.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/complex.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/core.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/date.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/date_time.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/exception.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/ostruct.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/range.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/rational.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/regexp.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/struct.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/symbol.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/add/time.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/common.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/ext.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/ext/.keep
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/generic_object.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/pure.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/pure/generator.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/pure/parser.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/lib/json/version.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail1.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail10.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail11.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail12.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail13.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail14.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail18.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail19.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail2.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail20.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail21.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail22.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail23.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail24.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail25.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail27.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail28.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail3.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail4.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail5.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail6.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail7.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail8.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/fail9.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/pass1.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/pass15.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/pass16.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/pass17.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/pass2.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/pass26.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/fixtures/pass3.json
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/setup_variant.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_addition.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_encoding.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_fixtures.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_generate.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_generic_object.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_string_matching.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_unicode.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tools/fuzz.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tools/server.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_addition.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_encoding.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_fixtures.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_generate.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_generic_object.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_string_matching.rb
C:/Ruby200/lib/ruby/gems/2.0.0/gems/json-1.8.1/tests/test_json_unicode.rb
Building native extensions.  This could take a while...
C:/Ruby200/bin/ruby.exe extconf.rb
creating Makefile
make "DESTDIR="
generating generator-i386-mingw32.def
compiling generator.c
linking shared-object json/ext/generator.so
make "DESTDIR=" install
/usr/bin/install -c -m 0755 generator.so ./.gem.20131220-7672-rd7993/json/ext
installing default generator libraries

C:/Ruby200/bin/ruby.exe extconf.rb
creating Makefile
make "DESTDIR="
generating parser-i386-mingw32.def
compiling parser.c
linking shared-object json/ext/parser.so
make "DESTDIR=" install
/usr/bin/install -c -m 0755 parser.so ./.gem.20131220-7672-15j70e0/json/ext
installing default parser libraries

Successfully installed json-1.8.1
Parsing documentation for json-1.8.1
Parsing sources...
unable to convert "\x90" from ASCII-8BIT to UTF-8 for lib/json/ext/generator.so, skipping
unable to convert "\x90" from ASCII-8BIT to UTF-8 for lib/json/ext/parser.so, skipping
100% [24/24]  lib/json/version.rb
Installing ri documentation for json-1.8.1
1 gem installed