PowerPC64 DT_RELR

[Alan Modra]

On Tue, Jan 18, 2022 at 05:32:37AM -0800, H.J. Lu wrote:
> I tried binutils master branch on glibc master branch:
> 
> $ readelf -r libc.so.6
> 
> Relocation section '.rela.dyn' at offset 0x21d38 contains 562 entries:
>   Offset          Info           Type           Sym. Value    Sym. Name + Addend
> 000000000000  000000000000 R_PPC64_NONE                         0
> 000000000000  000000000000 R_PPC64_NONE                         0
> 
> There are 238 R_PPC64_NONEs in libc.so.6 alone.  There is none
> for i686, x32 and x86-64.

Thanks for testing and finding the problem.  I did warn that DT_RELR
on ppc64 is experimental.  :-)

I had the SYMBOL_REFERENCES_LOCAL test in the wrong place.
check_relocs is too early to know whether a symbol is dynamic in a
shared library.  Lots of glibc symbols are made local by version
script, but that doesn't happen until size_dynamic_sections.

	* elf64-ppc.c (ppc64_elf_check_relocs): Don't count relative relocs
	here depending on SYMBOL_REFERENCES_LOCAL.
	(dec_dynrel_count): Likewise.
	(allocate_dynrelocs): Do so here instead.

diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 923c7a3b407..aeae3b7e640 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -5390,8 +5390,7 @@ ppc64_elf_check_relocs (bfd *abfd, struct bfd_link_info *info,
 		  if ((r_type == R_PPC64_ADDR64 || r_type == R_PPC64_TOC)
 		      && rel->r_offset % 2 == 0
 		      && sec->alignment_power != 0
-		      && ((!NO_OPD_RELOCS && is_opd)
-			  || (!ifunc && SYMBOL_REFERENCES_LOCAL (info, h))))
+		      && ((!NO_OPD_RELOCS && is_opd) || !ifunc))
 		    p->rel_count += 1;
 		}
 	      else
@@ -7287,8 +7286,7 @@ dec_dynrel_count (const Elf_Internal_Rela *rel,
 		  && sec->alignment_power != 0
 		  && ((!NO_OPD_RELOCS
 		       && ppc64_elf_section_data (sec)->sec_type == sec_opd)
-		      || (h->type != STT_GNU_IFUNC
-			  && SYMBOL_REFERENCES_LOCAL (info, h))))
+		      || h->type != STT_GNU_IFUNC))
 		p->rel_count -= 1;
 	      p->count -= 1;
 	      if (p->count == 0)
@@ -10016,7 +10014,7 @@ allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf)
 	  if (eh->elf.type == STT_GNU_IFUNC)
 	    sreloc = htab->elf.irelplt;
 	  count = p->count;
-	  if (info->enable_dt_relr)
+	  if (info->enable_dt_relr && SYMBOL_REFERENCES_LOCAL (info, h))
 	    count -= p->rel_count;
 	  sreloc->size += count * sizeof (Elf64_External_Rela);
 	}

-- 
Alan Modra
Australia Development Lab, IBM