Add ability to follow dwo links to readelf/objdump.

	* dwarf.c (dwo_name, dwo_dir, dwo_id, dwo_id_len): New variables.
	(read_and_display_attr_value): Record dwo variables if requested.
	(display_augmentation_data): Rename to display_data and make
	generic.
	(load_dwo_file): New function.  Loads a separate dwarf object
	file.
	(load_separate_debug_file): Add reporting and loading of separate
	dwarf objet files.
	* readelf.c (process_section_headers): Add do_debug_links to list
	of flags requiring a debug dump.
	(display_debug_section): Tidy up code.
	* doc/debug.options.texi: Add note that dwo links will also be
	followed.
	* testsuite/binutils-all/debuglink.s: Tidy code.
	* testsuite/binutils-all/dwo.s: New test file.
	* testsuite/binutils-all/readelf.wk2: New file - expected output
	from readelf.
	* testsuite/binutils-all/readelf.exp: Run the new test.

1 files changed, 31 insertions, 28 deletions

diff --git a/binutils/readelf.c b/binutils/readelf.c
index a372620c66..ea7cc3e18e 100644
--- a/binutils/readelf.c
+++ b/binutils/readelf.c
@@ -6084,7 +6084,7 @@ process_section_headers (Filedata * filedata)
 		|| do_debug_lines || do_debug_pubnames || do_debug_pubtypes
 		|| do_debug_aranges || do_debug_frames || do_debug_macinfo
 		|| do_debug_str || do_debug_loc || do_debug_ranges
-		|| do_debug_addr || do_debug_cu_index)
+		|| do_debug_addr || do_debug_cu_index || do_debug_links)
 	       && (const_strneq (name, ".debug_")
                    || const_strneq (name, ".zdebug_")))
 	{
@@ -13658,40 +13658,43 @@ display_debug_section (int shndx, Elf_Internal_Shdr * section, Filedata * fileda
 
   /* See if we know how to display the contents of this section.  */
   for (i = 0; i < max; i++)
-    if (streq (debug_displays[i].section.uncompressed_name, name)
-	|| (i == line && const_strneq (name, ".debug_line."))
-        || streq (debug_displays[i].section.compressed_name, name))
-      {
-	struct dwarf_section * sec = &debug_displays [i].section;
-	int secondary = (section != find_section (filedata, name));
+    {
+      enum dwarf_section_display_enum  id = (enum dwarf_section_display_enum) i;
+      struct dwarf_section_display *   display = debug_displays + i;
+      struct dwarf_section *           sec = & display->section;
 
-	if (secondary)
-	  free_debug_section ((enum dwarf_section_display_enum) i);
+      if (streq (sec->uncompressed_name, name)
+	  || (id == line && const_strneq (name, ".debug_line."))
+	  || streq (sec->compressed_name, name))
+	{
+	  bfd_boolean secondary = (section != find_section (filedata, name));
 
-	if (i == line && const_strneq (name, ".debug_line."))
-	  sec->name = name;
-	else if (streq (sec->uncompressed_name, name))
-	  sec->name = sec->uncompressed_name;
-	else
-	  sec->name = sec->compressed_name;
+	  if (secondary)
+	    free_debug_section (id);
 
-	if (load_specific_debug_section ((enum dwarf_section_display_enum) i,
-                                         section, filedata))
-	  {
-	    /* If this debug section is part of a CU/TU set in a .dwp file,
-	       restrict load_debug_section to the sections in that set.  */
-	    section_subset = find_cu_tu_set (filedata, shndx);
+	  if (i == line && const_strneq (name, ".debug_line."))
+	    sec->name = name;
+	  else if (streq (sec->uncompressed_name, name))
+	    sec->name = sec->uncompressed_name;
+	  else
+	    sec->name = sec->compressed_name;
 
-	    result &= debug_displays[i].display (sec, filedata);
+	  if (load_specific_debug_section (id, section, filedata))
+	    {
+	      /* If this debug section is part of a CU/TU set in a .dwp file,
+		 restrict load_debug_section to the sections in that set.  */
+	      section_subset = find_cu_tu_set (filedata, shndx);
 
-	    section_subset = NULL;
+	      result &= display->display (sec, filedata);
 
-	    if (secondary || (i != info && i != abbrev))
-	      free_debug_section ((enum dwarf_section_display_enum) i);
-	  }
+	      section_subset = NULL;
 
-	break;
-      }
+	      if (secondary || (id != info && id != abbrev))
+		free_debug_section (id);
+	    }
+	  break;
+	}
+    }
 
   if (i == max)
     {