Re: [PPL-devel] Re: Raising Prolog exceptions from C code (2nd attempt)

[Roberto Bagnara]

Manuel Carro wrote:
> > > I really feel this is a strong limitation of GNU Prolog:
> > > we cannot ask our users to recompile every library they use
> > > so as to make sure that -fomit-frame-pointer is used or
> > > left out consistently in all the builds.
>
>     One thing is that this option is among the ones which brings more
> speed (at least in ix86 architectures).  Ciao Prolog is also compiled
> with this option.

Right.  However, I believe here the point is another one: do GNU and
Ciao Prolog require all foreign code they interoperate with to be compiled
with -fomit-frame-pointer for proper operation?  And: to interoperate
with foreign code compiled without -fomit-frame-pointer, is it necessary
to recompile GNU and Ciao Prolog without -fomit-frame-pointer?

For GNU Prolog, the experiments conducted by Daniele and myself would
seem to indicate two positive answers.  Should that be confirmed, it would
constitute a serious drawback of GNU Prolog, since proper behavior should
not depend on how foreign code is compiled, provided the calling conventions
of the platform at hand are respected (and compiling with or without
-fomit-frame-pointer has no influence, AFAICT, on the calling conventions
used in the platforms we are talking about).
All the best

    Roberto

--
Prof. Roberto Bagnara
Computer Science Group
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:address@hidden