Re: Calling C from OCaml, GC problems

[David.Mentre@irisa.fr (David Mentré)]

Xavier Leroy <Xavier.Leroy@inria.fr> writes:

> >  2. when compiling, I've tons of warning like this:
> > bdd_interface.c: In function `mlbdd_alloc_manager':
> > bdd_interface.c:136: warning: left-hand operand of comma expression has no effect
> > bdd_interface.c:136: warning: unused variable `caml__dummy_result'
> 
> I think those warnings are harmless, and are due to the way the
> CAMLxxx macros are written in 2.04.  But only Damien Doligez knows for
> sure...

Yes. Having a deeper look at those macros, I've found that the first
warning as been fixed in ocaml 2.99 (the macros CAMLxparam referenced a
the caml__frame variable without using it).

However, the second warning is still there (even if harmless). The
problem is that the caml__dummy_##name variables are no longer
used. Such variable is only used to make some side-effects using C
'(stmt1, stmt2, ..., stmtN)' notation. I see no way to fix this. C lack
the Caml 'let _ ='. :)

Any way, many thanks for the feedback.
Best regards,
d. 
-- 
 David.Mentre@irisa.fr -- http://www.irisa.fr/prive/dmentre/
 Opinions expressed here are only mine.