> On 2020-12-05 3:10 a.m., Joel Brobecker wrote:
> > @@ -81,13 +133,26 @@ gdb_mpz::write (gdb::array_view<gdb_byte> buf, enum bfd_endian byte_order,
> >        mpz_add (exported_val.val, exported_val.val, neg_offset.val);
> >      }
> >
> > +  /* Do the export into a buffer allocated by GMP itself; that way,
> > +     we can detect cases where BUF is not large enough to export
> > +     our value, and thus avoid a buffer overlow.  Normally, this should
> > +     never happen, since we verified earlier that the buffer is large
> > +     enough to accomodate our value, but doing this allows us to be
> > +     extra safe with the export.
> > +
> > +     After verification that the export behaved as expected, we will
> > +     copy the data over to BUF.  */
> > +
> > +  size_t word_countp;
> > +  gdb::unique_xmalloc_ptr<void> exported
> > +    (mpz_export (NULL, &word_countp, -1 /* order */, buf.size () /* size */,
> > +		 endian, 0 /* nails */, exported_val.val));
> > +
> > +  gdb_assert (word_countp == 1);
> > +
> >    /* Start by clearing the buffer, as mpz_export only writes as many
> > -     bytes as it needs (including none, if the value to export is zero.  */
> 
> That comment is now stale.

Indeed. Thanks for catching that.

> Otherwise, that LGTM.

Thanks Simon. The patch is now in, with the correction above (a copy
of the patch is attached, for the record).

-- 
Joel