'addMetaObjectMethods' error

[crella6]

In file ./lib/Qt4.rb, before 'module Qt'
'require "#{ruby_version}/qtruby4"' should be changed to './lib/Qt/qtruby4'

After this change, the code still won't run.
ruby2.5 x86 raise an error,

In ./lib/Qt/qtruby4.rb:3079:
in initialize': undefined method addMetaObjectMethods' for Qt::Internal:Module (NoMethodError)

I grep the whole directory and still can't find the definition of 'addMetaObjectMethods'

Could it be fixed? Thanks for efforts.

[The3Null4Player613310]

@ryanmelt I seem to have the same problem on arch to some degree.
The error is really cryptic so any help you could offer would be greatly appreciated.