rdoc does not track C externs for classes/modules
When a *.c file describes a class, with methods, etc., and a *.rb exists owning the same class name, then the *.rb wins completely.
Example: ext/fiddle/closure.c and ext/fiddle/lib/fiddle/closure.rb The *.c includes two methods, but when the documentation is generated, on the the attributes described in the *.rb are present for the Fiddle::Closure class.
or maybe it is that ext/fiddle/closure.c is not getting picked up at all ...
There was a warning rdoc prints, something like 'enclosing class mFiddle of "Closure" not found'.
RDoc knows nothing about externs variables across classes so did not know that "Closure" meant Fiddle::Closure. As a hack I added an assignment of mFiddle an a #if 0 section.
RDoc could do this better.