jekyll mkmf.rb can’t find header files for ruby at /usr/share/include/ruby.h

We get the error when installing jekyll

[root@centos02 ~]# gem install jekyll bundler
Building native extensions.  This could take a while...
ERROR:  Error installing jekyll:
        ERROR: Failed to build gem native extension.

    /usr/bin/ruby extconf.rb
mkmf.rb can't find header files for ruby at /usr/share/include/ruby.h

Install ruby-devel to get the headers

[root@centos02 ~]# yum install ruby-devel
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base:
 * epel:
 * extras:
 * updates:
Resolving Dependencies
--> Running transaction check
---> Package ruby-devel.x86_64 0: will be installed
--> Finished Dependency Resolution

Dependencies Resolved

 Package            Arch           Version                   Repository    Size
 ruby-devel         x86_64          base         128 k

Transaction Summary
Install  1 Package

Total download size: 128 k
Installed size: 337 k
Is this ok [y/d/N]: y
Downloading packages:
ruby-devel-                     | 128 kB   00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : ruby-devel-                           1/1
  Verifying  : ruby-devel-                           1/1

  ruby-devel.x86_64 0: