Re: [Gcl-devel] Re: gcl/maxima on hppa

[Camm Maguire]

Greetings!

address@hidden (LaMont Jones) writes:

> On Fri, Sep 13, 2002 at 10:17:04AM -0400, Camm Maguire wrote:
> > Greetings!  I think I may have stumbled on a possible explanation for
> > gcl's build failure on hppa.  Hppa alone will not relocate (i.e. allow
> > dlopen to open) modules not compiled with -fPIC.  All other
> > architectures on which dlopen is currently used (alpha, ia64, mips,
> > mipsel)
> 
> Actually, mips and mipsel force -fPIC on all compiles.  The spec requires
> that shared objects be built with -fPIC.
> 

OK.  And on further investigation, the -fPIC theory is further
weakened by my finding that the i386 dlopen build works with -fPIC,
its just the i386 bfd build which breaks.  Still investigating this.

> > 1) gcl can also relocate and load objects via a direct call to the BFD
> >    library routine bfd_get_relocated_section_contents.  This method is
> >    currently used as the default on i386, sparc, ppc, s390, m68k and
> >    arm.  It is not yet fully implemented on hppa.  Completing this
> >    routine should enable a fully functional gcl, maxima, and in the
> >    hopefully near future acl2 on this platform.
> 
> Cool.
> 

I like it too :-).

> > 2) Find a way to load objects with dlopen without -fPIC.  Attempting
> >    this results in the error that a certain relocation output by the
> >    compiler cannot be handled by dlopen.  Perhaps there is some other
> >    gcc compiler option short of the full -fPIC which can avoid this
> >    relocation?
> 
> Nope.  The non-PIC is truly not position independent.
> 

They may not be position independent, but they are relocateable,
right?  I mean, that's how ld will work on .o files made without
-fPIC, no?  I guess I don't quite understand how other platforms have
been able to duplicate the relocation functionality of ld in dlopen
for non-fpic objects, but that on hppa, (and also possibly mips?),
this cannot be done?

> > In either case, I will need a knowledgeable hppa person to advise,
> > discuss and help generate patches for this to get fixed any time soon.
> > Gcl can build its own bfd library, so patches here can be simply
> > incorporated.
> 
> willy would be a good target.  I'm going to be out of town for a couple
> of weeks, but (if it's still pending) I'd be happy to help when I get
> back.

Wonderful!  Anyone have a contact address?

Take care,

> 
> lamont
> 
> 

-- 
Camm Maguire                                            address@hidden
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