[Opencxx-users] "ChangeDefaultMetaclass" and "metaclass declaration"

[Marc W. <Mar...@si...>]

In the documentation, there is written under 
"ChangeDefaultMetaclass" (page 22 of the PDF):

"It should be called by Initialized() defined for a 
metaclass loaded loaded by the -S option at the beginning. 
Otherwise, that metaclass should be explicitely loaded by 
the metaclass declaration, after which the new metaclass is 
effective."

This does not work!

 - I don't use the "-S" option
 - I don't use any "metaclass" declaration

 -> But the metaclass is still applied!

Why?!?


Problem: 

At first sight, one would think that everything is ok. if 
the metaclass is loaded and applied, but unfortunately it 
is also applied to all to all system libraries, where I 
don't want it. That's why I need the "metaclass 
declaration" to be able to tell the OpenC++ processor where 
to start applying the metaclass.

How can I do this?


(You can check the opencxx-problem.tar.gz file of my 
previous mail for my implementation, it requires my patch).


What do I want to do:

 - Add a function trace to all my classes without changing
   a single line!

How do I try to do it:

 - Automatically include file "fntrace.hxx" by passing
   option "-include fntrace.hxx" to the C preprocessor

 - Make my trace class the new default class, so it is
   applied to all classes.

What's the problem with this approach:

 - All included system headers are also instrumented,
   means added a function trace

 - But the header fntrace.hxx is included later, so
   the symbols of that header are unknown before

Possible solutions:

 - Find a way to include fntrace.hxx as very first file

 - Start OpenC++ metaclass instrumentation only after
   inclusion of fntrace.hxx (i.e. with a "metaclass
   declaration", by adding the line "metaclass
   IsTraceClass;" as last line in header fntrace.hxx)

The latter is exactly what I tried and why I send this error 
report.

Any other idea?


Thank you
Regards
Marc