An updated patch is attached that also avoids calling onload multiple times.

2010-02-20  Rafael Ávila de Espíndola <respindola@mozilla.com>

        * plugin.c (bfd_plugin_object_p): Correctly set the filesize
	and handle claim_file seeking. Only try to load the plugin once.

On 2011-02-08 22:17, Rafael Ávila de Espíndola wrote:
> I recently updated a plugin to use the file descriptor directly. This
> worked fine in gold, but had two issues using bfd (nm and ar):
> 
> *) The filesize was not being set.
> *) The code expected the claim_file callback to not seek.
> 
> That is not my understanding from reading the api documentation in
> http://gcc.gnu.org/wiki/whopr/driver, so the attached patch fixes both
> issues.

Cheers,
Rafael