Help with cpp woes

[Carl Lewis]

I am trying to port a fairly large piece of software (postgres)
which tries to be very clever with it's #define's, causing
the evaluation of a macro to yield yet another macro etc.
Unfortunately I can't get past the pre-processing to see if it'll 
compile ! Does anyone know if there are any undocumented flags for
AIX's version of cpp which make it behave in a reasonable manner ?

AIX's poor old cpp gives up the ghost about three macro levels down.
Unfortuantely I cannot repeat the bug with a simple test case.
xlc, bsdcc , cc all fail at various stages with both the inbuilt
and external cpp (/lib/). I've even tried /usr/lpp/X11/Xamples/util/cpp !
, further than that I've tried porting BSD4.3 cpp which doesn't
work either. (it doesn't understand #elif :-( ).

Does anyone have a solution in the way of flags or non brain dead cpp
source ?

Thanks
Carl, Programmer (etc) with University of Tasmania
AARN : C.S.Lewis at cs.utas.edu.au
       || carl at cs.utas.edu.au 
       || carl at probitas.cs.utas.edu.au
--
Carl, Programmer (etc) with University of Tasmania
Snail:  Computer Science Dept., University of Tasmania,
        GPO Box 252C, Hobart, TAS, 7001, Australia.
AARN : carl at cs.utas.edu.au