bfd/

	* elflink.c (elf_bfd_final_link): Don't output STT_SECTION symbol
	into .dynsym if elf_section_data (sec)->dynindx <= 0.
	Adjust counting of last_local.
	(_bfd_elf_link_renumber_dynsyms): Don't assign dynindx to sections
	other than SHT_PROGBITS/SHT_NOBITS and neither for .got/.got.plt/.plt
	created by the linker nor !SHF_ALLOC.

	* elf32-i386.c (elf_i386_finish_dynamic_sections): Point
	DT_PLTGOT to the start of the .got.plt section instead of the
	.got output section.  Set sh_entsize for .got section in addition
	to .got.plt.
	(elf_i386_relocate_section): Don't assume _GLOBAL_OFFSET_TABLE_
	is at sgot->output_section->vma.
	* elf64-x86-64.c (elf64_x86_64_finish_dynamic_sections): Point
	DT_PLTGOT to the start of the .got.plt section instead of the
	.got output section.
	(elf64_x86_64_relocate_section): Don't assume _GLOBAL_OFFSET_TABLE_
	is at sgot->output_section->vma.  Set sh_entsize for .got section
	in addition to .got.plt.
	* elf.c (_bfd_elf_print_private_bfd_data): Handle PT_GNU_RELRO.
	(bfd_section_from_phdr): Likewise.
	(map_sections_to_segments): Likewise.
	(assign_file_positions_for_segments): Likewise.
	(get_program_header_size): Likewise.
	* elflink.c (bfd_elf_size_dynamic_sections): Set
	elf_tdata (output_bfd)->relro from info->relro.
	* elf-bfd.h (struct elf_obj_tdata): Add relro field.
include/
	* bfdlink.h (struct bfd_link_info): Add relro, relro_start and
	relro_end fields.
	* elf/common.h (PT_GNU_EH_FRAME, PT_GNU_STACK): Add comments.
	(PT_GNU_RELRO): Define.
binutils/
	* readelf.c (get_segment_type): Handle PT_GNU_RELRO.
ld/
	* genscripts.sh: Generate -z combreloc -z now -z relro scripts
	for binaries, -shared and -pie.
	* emulparams/elf_i386.sh (SEPARATE_GOTPLT): Set.
	* emulparams/elf_x86_64.sh (SEPARATE_GOTPLT): Set.
	* emulparams/elf32ppc.sh (OTHER_READWRITE_SECTIONS): Rename to...
	(OTHER_RELRO_SECTIONS): ... this.
	* ldlex.l (DATA_SEGMENT_RELRO_END): Add.
	* emultempl/elf32.em (gld${EMULATION_NAME}_handle_option): Handle
	-z relro and -z norelro.
	(gld${EMULATION_NAME}_list_options): Add it to usage.
	(gld${EMULATION_NAME}_get_script): Return -z combreloc -z now
	-z relro scripts when appropriate.
	* scripttempl/elf.sc: Unset SEPARATE_GOTPLT if RELRO_NOW is set.
	Create separate .got.plt section if SEPARATE_GOTPLT.
	Move sections which are only written during relocation handling
	to the beginning of RW segment.  If NO_SMALL_DATA, move .got
	before .data.  Add DATA_SEGMENT_RELRO_END directive.
	Include OTHER_RELRO_SECTIONS.
	* ldgram.y (DATA_SEGMENT_RELRO_END): Add.
	* ldexp.c (exp_print_token): Handle DATA_SEGMENT_RELRO_END.
	(fold_unary): Likewise.
	(fold_binary): Handle -z relro.
	* ldexp.h (struct exp_data_seg): Add exp_dataseg_relro_seen and
	exp_dataseg_relro_adjust phases.  Add relro_end field.
	* ldmain.c (main): Initialize link_info.relro to FALSE.
	* ldlang.c (lang_size_sections): Handle -z relro.
ld/testsuite/
	* ld-i386/tlspic.rd: Adjust for section reordering changes
	and removal of unneeded STT_SECTION symbols from .dynsym.
	* ld-i386/tlspic.dd: Likewise.
	* ld-i386/tlspic.sd: Likewise.
	* ld-i386/tlsbin.rd: Likewise.
	* ld-i386/tlsbinpic.s: Likewise.
	* ld-i386/tlsbin.dd: Likewise.
	* ld-i386/tlsbin.sd: Likewise.
	* ld-i386/tlsnopic.rd: Likewise.
	* ld-i386/tlsnopic1.s: Likewise.
	* ld-i386/combreloc.d: Likewise.
	* ld-i386/tlsnopic.dd: Likewise.
	* ld-i386/tlsnopic.sd: Likewise.
	* ld-x86-64/tlspic.rd: Likewise.
	* ld-x86-64/tlspic.dd: Likewise.
	* ld-x86-64/tlsbin.dd: Likewise.
	* ld-x86-64/tlspic.sd: Likewise.
	* ld-x86-64/tlsbin.sd: Likewise.
	* ld-x86-64/tlspic.td: Likewise.
	* ld-x86-64/tlsbin.td: Likewise.
	* ld-x86-64/tlsbin.rd: Likewise.
	* ld-s390/tlspic1.s: Likewise.
	* ld-s390/tlsbinpic.s: Likewise.
	* ld-s390/tlspic.rd: Likewise.
	* ld-s390/tlsbin.rd: Likewise.
	* ld-s390/tlspic.dd: Likewise.
	* ld-s390/tlsbin.dd: Likewise.
	* ld-s390/tlsbin.sd: Likewise.
	* ld-s390/tlsbin.td: Likewise.
	* ld-s390/tlspic.sd: Likewise.
	* ld-s390/tlspic.td: Likewise.
	* ld-s390/tlspic1_64.s: Likewise.
	* ld-s390/tlsbinpic_64.s: Likewise.
	* ld-s390/tlspic_64.rd: Likewise.
	* ld-s390/tlsbin_64.rd: Likewise.
	* ld-s390/tlspic_64.dd: Likewise.
	* ld-s390/tlsbin_64.dd: Likewise.
	* ld-s390/tlspic_64.sd: Likewise.
	* ld-s390/tlspic_64.td: Likewise.
	* ld-s390/tlsbin_64.td: Likewise.
	* ld-s390/tlsbin_64.sd: Likewise.
	* ld-powerpc/tlsexe32.r: Likewise.
	* ld-powerpc/tlsso32.r: Likewise.
	* ld-powerpc/tlsso32.d: Likewise.
	* ld-powerpc/tlsso32.g: Likewise.
	* ld-powerpc/tlsso32.t: Likewise.
	* ld-powerpc/tlsexe.r: Likewise.
	* ld-powerpc/tlsso.r: Likewise.
	* ld-powerpc/tlsso.g: Likewise.
	* ld-powerpc/tlsexetoc.r: Likewise.
	* ld-powerpc/tlstocso.r: Likewise.
	* ld-powerpc/tlstocso.g: Likewise.
	* ld-ia64/tlspic.rd: Likewise.
	* ld-ia64/tlspic.dd: Likewise.
	* ld-ia64/tlspic.sd: Likewise.
	* ld-ia64/tlspic.td: Likewise.
	* ld-ia64/tlsbin.rd: Likewise.
	* ld-ia64/tlsbin.sd: Likewise.
	* ld-ia64/tlsbin.td: Likewise.
	* ld-elfvsb/elfvsb.exp: XFAIL non-PIC load offset tests on s390x.
	* ld-shared/shared.exp: Likewise.

9 files changed, 183 insertions, 22 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index a9088e57c96..fc12cb43e30 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,33 @@
+2004-05-11  Jakub Jelinek  <jakub@redhat.com>
+
+	* elflink.c (elf_bfd_final_link): Don't output STT_SECTION symbol
+	into .dynsym if elf_section_data (sec)->dynindx <= 0.
+	Adjust counting of last_local.
+	(_bfd_elf_link_renumber_dynsyms): Don't assign dynindx to sections
+	other than SHT_PROGBITS/SHT_NOBITS and neither for .got/.got.plt/.plt
+	created by the linker nor !SHF_ALLOC.
+
+	* elf32-i386.c (elf_i386_finish_dynamic_sections): Point
+	DT_PLTGOT to the start of the .got.plt section instead of the
+	.got output section.  Set sh_entsize for .got section in addition
+	to .got.plt.
+	(elf_i386_relocate_section): Don't assume _GLOBAL_OFFSET_TABLE_
+	is at sgot->output_section->vma.
+	* elf64-x86-64.c (elf64_x86_64_finish_dynamic_sections): Point
+	DT_PLTGOT to the start of the .got.plt section instead of the
+	.got output section.
+	(elf64_x86_64_relocate_section): Don't assume _GLOBAL_OFFSET_TABLE_
+	is at sgot->output_section->vma.  Set sh_entsize for .got section
+	in addition to .got.plt.
+	* elf.c (_bfd_elf_print_private_bfd_data): Handle PT_GNU_RELRO.
+	(bfd_section_from_phdr): Likewise.
+	(map_sections_to_segments): Likewise.
+	(assign_file_positions_for_segments): Likewise.
+	(get_program_header_size): Likewise.
+	* elflink.c (bfd_elf_size_dynamic_sections): Set
+	elf_tdata (output_bfd)->relro from info->relro.
+	* elf-bfd.h (struct elf_obj_tdata): Add relro field.
+
 2004-05-08  Alexandre Oliva  <aoliva@redhat.com>
 
 	* elf32-frv.c (_frvfdpic_add_dyn_reloc): Don't warn when we get
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h
index 9d0ec364b74..750cc1c675b 100644
--- a/bfd/elf-bfd.h
+++ b/bfd/elf-bfd.h
@@ -1211,6 +1211,9 @@ struct elf_obj_tdata
   /* Segment flags for the PT_GNU_STACK segment.  */
   unsigned int stack_flags;  
 
+  /* Should the PT_GNU_RELRO segment be emitted?  */
+  bfd_boolean relro;
+
   /* Symbol version definitions in external objects.  */
   Elf_Internal_Verdef *verdef;
 
diff --git a/bfd/elf.c b/bfd/elf.c
index 00443c2cc83..8e208c22e60 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -974,6 +974,7 @@ _bfd_elf_print_private_bfd_data (bfd *abfd, void *farg)
 	    case PT_TLS: pt = "TLS"; break;
 	    case PT_GNU_EH_FRAME: pt = "EH_FRAME"; break;
 	    case PT_GNU_STACK: pt = "STACK"; break;
+	    case PT_GNU_RELRO: pt = "RELRO"; break;
 	    default: sprintf (buf, "0x%lx", p->p_type); pt = buf; break;
 	    }
 	  fprintf (f, "%8s off    0x", pt);
@@ -2300,6 +2301,9 @@ bfd_section_from_phdr (bfd *abfd, Elf_Internal_Phdr *hdr, int index)
     case PT_GNU_STACK:
       return _bfd_elf_make_section_from_phdr (abfd, hdr, index, "stack");
 
+    case PT_GNU_RELRO:
+      return _bfd_elf_make_section_from_phdr (abfd, hdr, index, "relro");
+
     default:
       /* Check for any processor-specific program segment types.
          If no handler for them, default to making "segment" sections.  */
@@ -3547,6 +3551,21 @@ map_sections_to_segments (bfd *abfd)
       pm = &m->next;
     }
 
+  if (elf_tdata (abfd)->relro)
+    {
+      amt = sizeof (struct elf_segment_map);
+      m = bfd_zalloc (abfd, amt);
+      if (m == NULL)
+	goto error_return;
+      m->next = NULL;
+      m->p_type = PT_GNU_RELRO;
+      m->p_flags = PF_R;
+      m->p_flags_valid = 1;
+
+      *pm = m;
+      pm = &m->next;
+    }
+
   free (sections);
   sections = NULL;
 
@@ -4081,6 +4100,37 @@ Error: First section in segment (%s) starts at 0x%x whereas the segment starts a
 	      if (! m->p_paddr_valid)
 		p->p_paddr = phdrs_paddr;
 	    }
+	  else if (p->p_type == PT_GNU_RELRO)
+	    {
+	      Elf_Internal_Phdr *lp;
+
+	      for (lp = phdrs; lp < phdrs + count; ++lp)
+		{
+		  if (lp->p_type == PT_LOAD
+		      && lp->p_vaddr <= link_info->relro_end
+		      && lp->p_vaddr >= link_info->relro_start
+		      && lp->p_vaddr + lp->p_filesz
+			 >= link_info->relro_end)
+		    break;
+		}
+
+	      if (lp < phdrs + count
+		  && link_info->relro_end > lp->p_vaddr)
+		{
+		  p->p_vaddr = lp->p_vaddr;
+		  p->p_paddr = lp->p_paddr;
+		  p->p_offset = lp->p_offset;
+		  p->p_filesz = link_info->relro_end - lp->p_vaddr;
+		  p->p_memsz = p->p_filesz;
+		  p->p_align = 1;
+		  p->p_flags = (lp->p_flags & ~PF_W);
+		}
+	      else
+		{
+		  memset (p, 0, sizeof *p);
+		  p->p_type = PT_NULL;
+		}
+	    }
 	}
     }
 
@@ -4168,6 +4218,12 @@ get_program_header_size (bfd *abfd)
       ++segs;
     }
 
+  if (elf_tdata (abfd)->relro)
+    {
+      /* We need a PT_GNU_RELRO segment.  */
+      ++segs;
+    }
+
   for (s = abfd->sections; s != NULL; s = s->next)
     {
       if ((s->flags & SEC_LOAD) != 0
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c
index a53d93ecc1d..dee26a025cd 100644
--- a/bfd/elf32-i386.c
+++ b/bfd/elf32-i386.c
@@ -2261,24 +2261,29 @@ elf_i386_relocate_section (bfd *output_bfd,
 	  if (off >= (bfd_vma) -2)
 	    abort ();
 
-	  relocation = htab->sgot->output_offset + off;
+	  relocation = htab->sgot->output_section->vma
+		       + htab->sgot->output_offset + off
+		       - htab->sgotplt->output_section->vma
+		       - htab->sgotplt->output_offset;
 	  break;
 
 	case R_386_GOTOFF:
 	  /* Relocation is relative to the start of the global offset
 	     table.  */
 
-	  /* Note that sgot->output_offset is not involved in this
-	     calculation.  We always want the start of .got.  If we
-	     defined _GLOBAL_OFFSET_TABLE in a different way, as is
+	  /* Note that sgot is not involved in this
+	     calculation.  We always want the start of .got.plt.  If we
+	     defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
 	     permitted by the ABI, we might have to change this
 	     calculation.  */
-	  relocation -= htab->sgot->output_section->vma;
+	  relocation -= htab->sgotplt->output_section->vma
+			+ htab->sgotplt->output_offset;
 	  break;
 
 	case R_386_GOTPC:
 	  /* Use global offset table as symbol value.  */
-	  relocation = htab->sgot->output_section->vma;
+	  relocation = htab->sgotplt->output_section->vma
+		       + htab->sgotplt->output_offset;
 	  unresolved_reloc = FALSE;
 	  break;
 
@@ -2699,12 +2704,15 @@ elf_i386_relocate_section (bfd *output_bfd,
 	    abort ();
 	  if (r_type == ELF32_R_TYPE (rel->r_info))
 	    {
-	      relocation = htab->sgot->output_offset + off;
+	      bfd_vma g_o_t = htab->sgotplt->output_section->vma
+			      + htab->sgotplt->output_offset;
+	      relocation = htab->sgot->output_section->vma
+			   + htab->sgot->output_offset + off - g_o_t;
 	      if ((r_type == R_386_TLS_IE || r_type == R_386_TLS_GOTIE)
 		  && tls_type == GOT_TLS_IE_BOTH)
 		relocation += 4;
 	      if (r_type == R_386_TLS_IE)
-		relocation += htab->sgot->output_section->vma;
+		relocation += g_o_t;
 	      unresolved_reloc = FALSE;
 	    }
 	  else
@@ -2761,7 +2769,11 @@ elf_i386_relocate_section (bfd *output_bfd,
 		  if (tls_type == GOT_TLS_IE_BOTH)
 		    off += 4;
 		}
-	      bfd_put_32 (output_bfd, htab->sgot->output_offset + off,
+	      bfd_put_32 (output_bfd,
+			  htab->sgot->output_section->vma
+			  + htab->sgot->output_offset + off
+			  - htab->sgotplt->output_section->vma
+			  - htab->sgotplt->output_offset,
 			  contents + roff + 8);
 	      /* Skip R_386_PLT32.  */
 	      rel++;
@@ -2823,7 +2835,10 @@ elf_i386_relocate_section (bfd *output_bfd,
 	      bfd_elf32_swap_reloc_out (output_bfd, &outrel, loc);
 	      htab->tls_ldm_got.offset |= 1;
 	    }
-	  relocation = htab->sgot->output_offset + off;
+	  relocation = htab->sgot->output_section->vma
+		       + htab->sgot->output_offset + off
+		       - htab->sgotplt->output_section->vma
+		       - htab->sgotplt->output_offset;
 	  unresolved_reloc = FALSE;
 	  break;
 
@@ -3159,7 +3174,8 @@ elf_i386_finish_dynamic_sections (bfd *output_bfd,
 	      continue;
 
 	    case DT_PLTGOT:
-	      dyn.d_un.d_ptr = htab->sgot->output_section->vma;
+	      s = htab->sgotplt;
+	      dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
 	      break;
 
 	    case DT_JMPREL:
@@ -3245,6 +3261,10 @@ elf_i386_finish_dynamic_sections (bfd *output_bfd,
 
       elf_section_data (htab->sgotplt->output_section)->this_hdr.sh_entsize = 4;
     }
+
+  if (htab->sgot && htab->sgot->_raw_size > 0)
+    elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize = 4;
+
   return TRUE;
 }
 
diff --git a/bfd/elf64-x86-64.c b/bfd/elf64-x86-64.c
index ee1b14e193f..f9eb7db6434 100644
--- a/bfd/elf64-x86-64.c
+++ b/bfd/elf64-x86-64.c
@@ -1911,9 +1911,11 @@ elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
 	  if (off >= (bfd_vma) -2)
 	    abort ();
 
-	  relocation = htab->sgot->output_offset + off;
-	  if (r_type == R_X86_64_GOTPCREL)
-	    relocation += htab->sgot->output_section->vma;
+	  relocation = htab->sgot->output_section->vma
+		       + htab->sgot->output_offset + off;
+	  if (r_type != R_X86_64_GOTPCREL)
+	    relocation -= htab->sgotplt->output_section->vma
+			  - htab->sgotplt->output_offset;
 
 	  break;
 
@@ -2664,7 +2666,8 @@ elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *inf
 	      continue;
 
 	    case DT_PLTGOT:
-	      dyn.d_un.d_ptr = htab->sgot->output_section->vma;
+	      s = htab->sgotplt;
+	      dyn.d_un.d_ptr = s->output_section->vma + s->output_offset;
 	      break;
 
 	    case DT_JMPREL:
@@ -2755,6 +2758,10 @@ elf64_x86_64_finish_dynamic_sections (bfd *output_bfd, struct bfd_link_info *inf
 	GOT_ENTRY_SIZE;
     }
 
+  if (htab->sgot && htab->sgot->_raw_size > 0)
+    elf_section_data (htab->sgot->output_section)->this_hdr.sh_entsize
+      = GOT_ENTRY_SIZE;
+
   return TRUE;
 }
 
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 32f42641689..cee59096a52 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -622,8 +622,36 @@ _bfd_elf_link_renumber_dynsyms (bfd *output_bfd, struct bfd_link_info *info)
     {
       asection *p;
       for (p = output_bfd->sections; p ; p = p->next)
-	if ((p->flags & SEC_EXCLUDE) == 0)
-	  elf_section_data (p)->dynindx = ++dynsymcount;
+	if ((p->flags & SEC_EXCLUDE) == 0
+	    && (p->flags & SEC_ALLOC) != 0)
+	  switch (elf_section_data (p)->this_hdr.sh_type)
+	    {
+	    case SHT_PROGBITS:
+	    case SHT_NOBITS:
+	      /* If sh_type is yet undecided, assume it could be
+		 SHT_PROGBITS/SHT_NOBITS.  */
+	    case SHT_NULL:
+	      if (strcmp (p->name, ".got") == 0
+		  || strcmp (p->name, ".got.plt") == 0
+		  || strcmp (p->name, ".plt") == 0)
+		{
+		  asection *ip;
+		  bfd *dynobj = elf_hash_table (info)->dynobj;
+
+		  if (dynobj != NULL
+		      && (ip = bfd_get_section_by_name (dynobj, p->name))
+			 != NULL
+		      && (ip->flags & SEC_LINKER_CREATED)
+		      && ip->output_section == p)
+		    continue;
+		}
+	      elf_section_data (p)->dynindx = ++dynsymcount;
+	      break;
+	      /* There shouldn't be section relative relocations
+		 against any other section.  */
+	    default:
+	      break;
+	    }
     }
 
   if (elf_hash_table (info)->dynlocal)
@@ -4621,6 +4649,7 @@ bfd_elf_size_dynamic_sections (bfd *output_bfd,
   if (!is_elf_hash_table (info->hash))
     return TRUE;
 
+  elf_tdata (output_bfd)->relro = info->relro;
   if (info->execstack)
     elf_tdata (output_bfd)->stack_flags = PF_R | PF_W | PF_X;
   else if (info->noexecstack)
@@ -7654,16 +7683,18 @@ bfd_elf_final_link (bfd *abfd, struct bfd_link_info *info)
 	      bfd_byte *dest;
 	      long dynindx;
 
-	      indx = elf_section_data (s)->this_idx;
 	      dynindx = elf_section_data (s)->dynindx;
+	      if (dynindx <= 0)
+		continue;
+	      indx = elf_section_data (s)->this_idx;
 	      BFD_ASSERT (indx > 0);
 	      sym.st_shndx = indx;
 	      sym.st_value = s->vma;
 	      dest = dynsym + dynindx * bed->s->sizeof_sym;
+	      if (last_local < dynindx)
+		last_local = dynindx;
 	      bed->s->swap_symbol_out (abfd, &sym, dest, 0);
 	    }
-
-	  last_local = bfd_count_sections (abfd);
 	}
 
       /* Write out the local dynsyms.  */
diff --git a/include/ChangeLog b/include/ChangeLog
index 4e92371d1c2..804d97f7128 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,10 @@
+2004-05-11  Jakub Jelinek  <jakub@redhat.com>
+
+	* bfdlink.h (struct bfd_link_info): Add relro, relro_start and
+	relro_end fields.
+	* elf/common.h (PT_GNU_EH_FRAME, PT_GNU_STACK): Add comments.
+	(PT_GNU_RELRO): Define.
+
 2004-05-04  Andreas Jaeger  <aj@suse.de>
 
 	* demangle.h: Do not use C++ reserved keyword typename as
diff --git a/include/bfdlink.h b/include/bfdlink.h
index cc2043e10ed..881d7d4796d 100644
--- a/include/bfdlink.h
+++ b/include/bfdlink.h
@@ -302,6 +302,9 @@ struct bfd_link_info
      flags.  */
   unsigned int noexecstack: 1;
 
+  /* TRUE if PT_GNU_RELRO segment should be created.  */
+  unsigned int relro: 1;
+
   /* What to do with unresolved symbols in an object file.
      When producing executables the default is GENERATE_ERROR.
      When producing shared libraries the default is IGNORE.  The
@@ -391,6 +394,9 @@ struct bfd_link_info
 
   /* May be used to set DT_FLAGS_1 for ELF. */
   bfd_vma flags_1;
+
+  /* Start and end of RELRO region.  */
+  bfd_vma relro_start, relro_end;
 };
 
 /* This structures holds a set of callback functions.  These are
diff --git a/include/elf/common.h b/include/elf/common.h
index 8ebc2cf4724..dbcb5d2795d 100644
--- a/include/elf/common.h
+++ b/include/elf/common.h
@@ -288,8 +288,9 @@
 #define PT_LOPROC	0x70000000	/* Processor-specific */
 #define PT_HIPROC	0x7FFFFFFF	/* Processor-specific */
 
-#define PT_GNU_EH_FRAME	(PT_LOOS + 0x474e550)
-#define PT_GNU_STACK	(PT_LOOS + 0x474e551)
+#define PT_GNU_EH_FRAME	(PT_LOOS + 0x474e550) /* Frame unwind information */
+#define PT_GNU_STACK	(PT_LOOS + 0x474e551) /* Stack flags */
+#define PT_GNU_RELRO	(PT_LOOS + 0x474e552) /* Read-only after relocation */
 
 /* Program segment permissions, in program header p_flags field.  */