Fix PR12762 using linkonce sections in plugin bfd

[H.J. Lu]

On Sat, Aug 13, 2011 at 2:59 AM, Alan Modra <amodra@gmail.com> wrote:
> Revised patch.  This one gives the plugin comdat_key symbols sections
> named .gnu.linkonce.t.<comdat_key>, so that SEC_LINK_ONCE gets set for
> the sections when recreating them during bfd_make_readable().
>
> I've also given the COFF backend its own bfd_section_already_linked
> and tidied the existing bfd_section_already_linked functions.  I'd
> appreciate someone familiar with our COFF support reviewing
> _bfd_coff_section_already_linked in case I've made some glaring
> mistakes..  The old code basically matched on section name, but if
> both sections had a comdat symbol then the symbols had to match too.
> That meant a comdat section could match a non-comdat section with the
> same name, something the new code specifically disallows, and anyway
> is a side-effect of hashing on the comdat key.  COFF also gets the
> benefit of the ELF code for SEC_LINK_DUPLICATES_SAME_CONTENTS, so
> section contents are actually checked now.
>
> bfd/
>        PR ld/12762
>        * bfd-in.h (struct bfd_section_already_linked): Forward declare.
>        (_bfd_handle_already_linked): Declare.
>        * coff-alpha.c (_bfd_ecoff_section_already_linked): Define as
>        _bfd_coff_section_already_linked.
>        * coff-mips.c (_bfd_ecoff_section_already_linked): Likewise.
>        * coffcode.h (coff_section_already_linked): Likewise.
>        * cofflink.c (coff_link_add_symbols): Revert 2011-07-09 changes.
>        * elf-bfd.h: Likewise.
>        * libbfd-in.h: Likewise.
>        * targets.c: Likewise.
>        * linker.c (bfd_section_already_linked): Likewise.
>        (bfd_section_already_linked_table_lookup): Likewise.
>        (bfd_section_already_linked_table_insert): Likewise.
>        (_bfd_generic_section_already_linked): Likewise.  Call
>        _bfd_handle_already_linked.
>        (_bfd_handle_already_linked): New function, split out from..
>        * elflink.c (_bfd_elf_section_already_linked): ..here.  Revert
>        2011-07-09 changes.  Avoid unnecessary strcmp when matching
>        already_linked_list entries.  Match plugin linkonce section.
>        (section_signature): Delete.
>        * coffgen.c (_bfd_coff_section_already_linked): New function.
>        * libcoff-in.h (_bfd_coff_section_already_linked): Declare.
>        * libbfd.h: Regenerate.
>        * libcoff.h: Regenerate.
>        * bfd-in2.h: Regenerate.
> ld/
>        PR ld/12762
>        * ldlang.c (section_already_linked): Revert 2011-07-09 changes.
>        * plugin.c: Likewise.
>        (asymbol_from_plugin_symbol): Create linkonce section for syms
>        with comdat_key.
>

It works.

Thanks.


-- 
H.J.