Ruby on Rails in Windows: Error in installing DevKit

Question

I'm new in ROR and I'm trying to install DevKit but I get some errors. I use Win7-64bit and i installed DevKit-mingw64-64-4.7.2-20130224-1432-sfx. I followed the installation in github. Honestly, the errors are not clear and I can't find out what I should do to fix the problem.

 C:\Devkit>type config.yml
 This configuration file contains the absolute path locations of all
 installed Rubies to be enhanced to work with the DevKit. This config
 file is generated by the 'ruby dk.rb init' step and may be modified
 before running the 'ruby dk.rb install' step. To include any installed
 Rubies that were not automagically discovered, simply add a line below
 the triple hyphens with the absolute path to the Ruby root directory.

Example:
--
- C:/ruby19trunk
- C:/ruby192dev
--
c:/Ruby22

then

C:\Devkit>ruby dk.rb install

[INFO] Skipping existing gem override for '    c:/Ruby22'
[WARN] Skipping existing DevKit helper library for '    c:/Ruby22'

and

C:\Devkit>gem install json --platform=ruby   
Temporarily enhancing PATH to include DevKit...
Building native extensions. This could take a while...
ERROR: Error installing json:
ERROR: Failed to build gem native extension.

c:/Ruby22/bin/ruby.exe -r ./siteconf20150524-7692-son84q.rb extconf.rb

creating Makefile    
make "DESTDIR=" clean
make "DESTDIR="

   generating generator-i386-mingw32.def
   compiling     generator.c
   In file included from     c:/Ruby22/include/ruby-2.2.0/ruby.h:33:0,
   from ../fbuffer/fbuffer.h:5,
   from     generator.c:1:
   c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:111:14: error: size of array 'ruby_chec
   k_sizeof_voidp' is negative
   In file included from     c:/Ruby22/include/ruby-2.2.0/ruby.h:33:0,
   from ../fbuffer/fbuffer.h:5,
   from     generator.c:1:

c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h: In function 'rb_obj_freeze_inline':
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1156:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1157:2: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1158:6: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1158:27: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h: In function 'rb_data_object_get':
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1192:13: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h: In function 'rb_obj_written':
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1271:10: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1271:34: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h: In function 'rb_num2char_inline':
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1344:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1344:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1344:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1344:36: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1344:36: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1344:36: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1345:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1345:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1345:9: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h: In function 'rb_class_of':
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1670:12: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h: In function 'rb_type':
c:/Ruby22/include/ruby-2.2.0/ruby/ruby.h:1687:12: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]

In file included from     generator.c:1:0:
../fbuffer/fbuffer.h: In function 'fbuffer_append_str':
../fbuffer/fbuffer.h:127:25: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
../fbuffer/fbuffer.h:127:25: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
../fbuffer/fbuffer.h:127:25: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]

generator.c: In function 'convert_UTF8_to_JSON_ASCII':
generator.c:129:35: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:129:35: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:129:35: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:130:38: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:130:38: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:130:38: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'convert_UTF8_to_JSON':
generator.c:227:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:227:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:227:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:228:25: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:228:25: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:228:25: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'cState_configure':
generator.c:559:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:559:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:559:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:560:34: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:560:34: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:560:34: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:567:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:567:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:567:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:568:33: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:568:33: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:568:33: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:575:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:575:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:575:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:576:40: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:576:40: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:576:40: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:583:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:583:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:583:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:584:36: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:584:36: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:584:36: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:591:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:591:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:591:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:592:37: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:592:37: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:592:37: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'set_state_ivars':
generator.c:640:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:640:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:640:21: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:642:24: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:642:24: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:642:24: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'generate_json_object':
generator.c:727:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:727:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:727:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'generate_json_array':
generator.c:773:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:773:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:773:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'isArrayOrObject':
generator.c:930:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:930:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:930:23: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:931:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:931:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:931:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'cState_indent_set':
generator.c:1055:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1055:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1055:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1064:32: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1064:32: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1064:32: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'cState_space_set':
generator.c:1093:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1093:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1093:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1102:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1102:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1102:31: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'cState_space_before_set':
generator.c:1129:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1129:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1129:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1138:38: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1138:38: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1138:38: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'cState_object_nl_set':
generator.c:1167:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1167:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1167:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1175:35: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1175:35: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1175:35: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c: In function 'cState_array_nl_set':
generator.c:1202:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1202:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1202:11: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1210:34: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1210:34: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
generator.c:1210:34: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
make: *** [generator.o] Error 1

make failed, exit code 2

Gem files will remain installed in     c:/Ruby22/lib/ruby/gems/2.2.0/gems/json-1.8.2
for inspection.
Results logged to     c:/Ruby22/lib/ruby/gems/2.2.0/extensions/x86-mingw32/2.2.0/jso
n-1.8.2/gem_make.out

Answer 1

I had the same set of errors and I resolved it by using the 32bit version of the devkit.

Even though the OS I am running appears to be Windows 7 64-bit the Ruby installation from the Ruby installer appears to have been 32-bit as found by:

C:\>ruby -v
ruby 2.2.3p173 (2015-08-18 revision 51636) [i386-mingw32]

Using the 32bit devkit (DevKit-mingw64-32-4.7.2-20130224-1151-sfx.exe) appears to have worked for me.