[PATCH] elf: Get the real kept section

[H.J. Lu]

On Fri, Nov 27, 2020 at 2:27 PM Alan Modra <amodra@gmail.com> wrote:
>
> On Fri, Nov 27, 2020 at 04:57:05PM +0100, Hans-Peter Nilsson via Binutils wrote:
> > I'll have to investigate this on my side.
>
> FWIW, I didn't see any cris fails either.  My current list of fails
> for the new test is:
>
> $ grep 26936 gastest_results
> am33_2.0-linux  FAIL: ld-elf/pr26936
> arc-elf  FAIL: ld-elf/pr26936
> arm-symbianelf  FAIL: ld-elf/pr26936
> hppa64-hp-hpux11.23  FAIL: ld-elf/pr26936
> mips-sgi-irix6  FAIL: ld-elf/pr26936
> mipstx39-elf  FAIL: ld-elf/pr26936
> mn10300-elf  FAIL: ld-elf/pr26936
> riscv64-linux  FAIL: ld-elf/pr26936
> xtensa-elf  FAIL: ld-elf/pr26936
>

linkonce section may not be mixed with comdat section.  For xtensa-elf,

COMDAT group section [    1] `.group' [__x86.get_pc_thunk.bx] contains
3 sections:
   [Index]    Name
   [    5]   .text.__x86.get_pc_thunk.bx
   [   15]   .xt.prop.bx
   [   16]   .rela.xt.prop.bx

elflink.c has
 /* A single member comdat group section may be discarded by a
     linkonce section and vice versa.  */
  if ((flags & SEC_GROUP) != 0)
    {
      asection *first = elf_next_in_group (sec);

      if (first != NULL && elf_next_in_group (first) == first)
        /* Check this single member group against linkonce sections.  */
        for (l = already_linked_list->entry; l != NULL; l = l->next)
          if ((l->sec->flags & SEC_GROUP) == 0
              && bfd_elf_match_symbols_in_sections (l->sec, first, info))
            {
              first->output_section = bfd_abs_section_ptr;
              first->kept_section = l->sec;
              sec->output_section = bfd_abs_section_ptr;
              break;
            }
    }


-- 
H.J.