* readelf.c (do_archive_index): New.

(options): Add -c and --archive-index option.
  (usage): Add -c option.
  (parse_args): Add c option parsing.
  (process_archive): Dump archive index.
* NEWS: Mention the new feature.
* doc/binutils.texi: Document the new feature.

binutils/doc/binutils.texi

@@ -3688,6 +3688,7 @@ readelf [@option{-a}|@option{--all}]
         [@option{-D}|@option{--use-dynamic}]
         [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
         [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
+        [@option{-c}|@option{--archive-index}]
         [@option{-w[liaprmfFsoR]}|
          @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
         [@option{-I}|@option{-histogram}]
@@ -3819,6 +3820,13 @@ Displays the contents of the indicated section as printable strings.
 A number identifies a particular section by index in the section table;
 any other string identifies all sections with that name in the object file.
 
+@item -c
+@itemx --archive-index
+@cindex Archive file symbol index information
+Displays the file symbol index infomation contained in the header part
+of binary archives.  Performs the same function as the @option{t}
+command to @command{ar}, but without using the BFD library.  @xref{ar}.
+
 @item -w[liaprmfFsoR]
 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
 Displays the contents of the debug sections in the file, if any are