bfd/

* elflink.c (elf_finalize_dynstr): Skip shared aux structure.
	(bfd_elf_size_dynamic_sections): Create default version definition.
	(elf_link_output_extsym): Adjust for default symbol version.
include/
	* bfdlink.h (struct bfd_link_info): Add create_default_symver.
ld/
	* ld.texinfo: Document --default-symver.
	* ldmain.c (main): Set link_info.create_default_symver.
	* lexsup.c (enum option_values): Add OPTION_DEFAULT_SYMVER.
	(ld_options): Add default-symver.
	(parse_args): Handle OPTION_DEFAULT_SYMVER.
ld/testsuite/
	* ld-elfvers/vers.exp (build_binary): Add ldargs parameter.
	(build_vers_lib_pic_flags): New function.
	Add vers29 test.
	* ld-elfvers/vers29.c: New file.
	* ld-elfvers/vers29.dsym: New file.
	* ld-elfvers/vers29.ver: New file.

include/bfdlink.h

@@ -262,6 +262,9 @@ struct bfd_link_info
   /* TRUE if ok to have version with no definition.  */
   unsigned int allow_undefined_version: 1;
 
+  /* TRUE id a fedault symbol version should be created and used.  */
+  unsigned int create_default_symver: 1;
+
   /* TRUE if symbols should be retained in memory, FALSE if they
      should be freed and reread.  */
   unsigned int keep_memory: 1;