Re: [Sablevm-developer] powerpc port status

[David P. B. <db...@CS...>]

Hello,

I will send a bug report to the libffi2 maintainers.

I found another bug about libffi2.  It does not passed properly
args of type ffi_type_uint8.

I will patch the code temporarily as suggested by Etienne to get around
these bugs.


David


On Fri, Dec 13, 2002 at 05:49:16PM -0500, Etienne M. Gagnon wrote:
> On Fri, Dec 13, 2002 at 05:18:42PM -0500, David Paul BELANGER wrote:
> > Accessing the value simply with:
> > params[0].jint =3D result[0].jint;
> >...
> > The other possible fix is to take byte at offset 3 for big endian
> > machines:
> > *(((unsigned char*) &v) + 3)
> > this does not rely on the layout of the union in memory.
>=20
> Yes, it actually does!  So, this would be wrong, as libffi was given
> ((unsigned char*) &v) as the location to store a "char", not and
> "int".  So, SableVM's source code is correct.
>=20
> "params[0].jint =3D result[0].jint;" should fail on a big-endian
> machine!  (It makes sense for this code *not* to work on both big and
> little-endian machines, if a "char" value was stored at &result).
>=20
> Maybe we should add an "#if defined(LIBFFIBUG) ... #endif" clause with
> the temporary bug evasion for now, and submit a bug against libffi
> (try "reportbug libffi2" on Debian, assuming reportbug is installed).
>=20
> Etienne
>=20
> --=20
> Etienne M. Gagnon                    http://www.info.uqam.ca/~egagnon/
> SableVM:                                       http://www.sablevm.org/
> SableCC:                                       http://www.sablecc.org/

--=20

---

David B=E9langer
Graduate Student
School of Computer Science
McGill University
Office: MC226

Web page:   http://www.cs.mcgill.ca/~dbelan2/
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