constify elfNN_bed

elfNN_bed was made writable as an expedient means of communicating
ld -z max-page-size and ld -z common-page-size values to BFD linker
code, and even for objcopy to communicate segment alignment between
copy_private_bfd_data, rewrite_elf_program_header and
assign_file_positions_for_load_sections.  Some time later elfNN_bed
elf_osabi was written by gas.  It turns out none of these
modifications to elfNN_bed was necessary, so make it const again.

include/
	* bfdlink.h (struct bfd_link_info): Add maxpagesize and
	commonpagesize.
bfd/
	* elfxx-target.h (elfNN_bed): Constify.
	* bfd.c (bfd_elf_set_pagesize): Delete.
	(bfd_emul_set_maxpagesize, bfd_emul_set_commonpagesize): Delete.
	* elf.c (get_program_header_size): Get commonpagesize from
	link info.
	(_bfd_elf_map_sections_to_segments): Get maxpagesize from link info.
	(assign_file_positions_for_load_sections): Likewise.
	(assign_file_positions_for_non_load_sections): Likewise.
	(rewrite_elf_program_header): Add maxpagesize param.  Set map_p_align.
	(copy_private_bfd_data): Don't call bfd_elf_set_maxpagesize.
	Instead pass maxpagesize to rewrite_elf_program_header.
	* elf32-nds32.c (relax_range_measurement): Add link_info param.
	Get maxpagesize from link_info.  Adjust caller.
	* bfd-in2.h: Regenerate.
gas/
	* config/obj-elf.c (obj_elf_section): Don't set elf_osabi here.
	(obj_elf_type): Likewise.
ld/
	* ld.h (ld_config_type): Delete maxpagesize and commonpagesize.
	* emultempl/elf.em: Use link_info rather than config
	for maxpagesize and commonpagesize.
	* emultempl/ppc32elf.em: Likewise.
	* ldexp.c (fold_binary, fold_name): Likewise.
	* ldemul.c (after_parse_default): Likewise.
	(set_output_arch_default): Don't call bfd_emul_set_maxpagesize
	or bfd_emul_set_commonpagesize.

2 files changed, 16 insertions, 16 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 1a6c85a..2816395 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,8 @@
+2020-12-16  Alan Modra  <amodra@gmail.com>
+
+	* config/obj-elf.c (obj_elf_section): Don't set elf_osabi here.
+	(obj_elf_type): Likewise.
+
 2020-12-15  Alan Modra  <amodra@gmail.com>
 
 	PR 27071
diff --git a/gas/config/obj-elf.c b/gas/config/obj-elf.c
index bee95c3..d030b54 100644
--- a/gas/config/obj-elf.c
+++ b/gas/config/obj-elf.c
@@ -1425,13 +1425,13 @@ obj_elf_section (int push)
 
   if ((gnu_attr & (SHF_GNU_MBIND | SHF_GNU_RETAIN)) != 0)
     {
-      struct elf_backend_data *bed;
+      const struct elf_backend_data *bed;
       bfd_boolean mbind_p = (gnu_attr & SHF_GNU_MBIND) != 0;
 
       if (mbind_p && (attr & SHF_ALLOC) == 0)
 	as_bad (_("SHF_ALLOC isn't set for GNU_MBIND section: %s"), name);
 
-      bed = (struct elf_backend_data *) get_elf_backend_data (stdoutput);
+      bed = get_elf_backend_data (stdoutput);
 
       if (bed->elf_osabi != ELFOSABI_GNU
 	  && bed->elf_osabi != ELFOSABI_FREEBSD
@@ -1440,9 +1440,6 @@ obj_elf_section (int push)
 		mbind_p ? "GNU_MBIND" : "GNU_RETAIN");
       else
 	{
-	  if (bed->elf_osabi == ELFOSABI_NONE)
-	    bed->elf_osabi = ELFOSABI_GNU;
-
 	  if (mbind_p)
 	    elf_tdata (stdoutput)->has_gnu_osabi |= elf_gnu_osabi_mbind;
 	  if ((gnu_attr & SHF_GNU_RETAIN) != 0)
@@ -2361,13 +2358,12 @@ obj_elf_type (int ignore ATTRIBUTE_UNUSED)
 	   || strcmp (type_name, "10") == 0
 	   || strcmp (type_name, "STT_GNU_IFUNC") == 0)
     {
-      struct elf_backend_data *bed;
+      const struct elf_backend_data *bed;
 
-      bed = (struct elf_backend_data *) get_elf_backend_data (stdoutput);
-      if (bed->elf_osabi == ELFOSABI_NONE)
-	bed->elf_osabi = ELFOSABI_GNU;
-      else if (bed->elf_osabi != ELFOSABI_GNU
-	       && bed->elf_osabi != ELFOSABI_FREEBSD)
+      bed = get_elf_backend_data (stdoutput);
+      if (bed->elf_osabi != ELFOSABI_NONE
+	  && bed->elf_osabi != ELFOSABI_GNU
+	  && bed->elf_osabi != ELFOSABI_FREEBSD)
 	as_bad (_("symbol type \"%s\" is supported only by GNU "
 		  "and FreeBSD targets"), type_name);
       /* MIPS targets do not support IFUNCS.  */
@@ -2379,12 +2375,11 @@ obj_elf_type (int ignore ATTRIBUTE_UNUSED)
     }
   else if (strcmp (type_name, "gnu_unique_object") == 0)
     {
-      struct elf_backend_data *bed;
+      const struct elf_backend_data *bed;
 
-      bed = (struct elf_backend_data *) get_elf_backend_data (stdoutput);
-      if (bed->elf_osabi == ELFOSABI_NONE)
-	bed->elf_osabi = ELFOSABI_GNU;
-      else if (bed->elf_osabi != ELFOSABI_GNU)
+      bed = get_elf_backend_data (stdoutput);
+      if (bed->elf_osabi != ELFOSABI_NONE
+	  && bed->elf_osabi != ELFOSABI_GNU)
 	as_bad (_("symbol type \"%s\" is supported only by GNU targets"),
 		type_name);
       elf_tdata (stdoutput)->has_gnu_osabi |= elf_gnu_osabi_unique;