PR ld/12942

	PR ld/12942
bfd/
	* elflink.c (elf_link_add_object_symbols): Use elf_discarded_section
	rather than kept_section to determine whether a symbol is from
	a discarded section.
	* cofflink.c (coff_link_add_symbols): Make symbols from discarded
	sections appear undefined.

	* elf-bfd.h (_bfd_elf_section_already_linked): Replace
	"asection *" with "struct already_linked *".
	* libbfd-in.h (_bfd_nolink_section_already_linked): Likewise.
	(_bfd_generic_section_already_linked): Likewise.
	(bfd_section_already_linked_table_insert): Likewise.
	(struct already_linked): New.
	(struct bfd_section_already_linked): Use it.
	* elflink.c (_bfd_elf_section_already_linked): Replace.
	"asection *" with "struct already_linked *".  Replace the plugin
	dummy with the LTO output.
	* linker.c (_bfd_generic_section_already_linked): Likewise.
	* targets.c (struct already_linked): Add forward declaration.
	(bfd_target): Replace "struct bfd_section *" with
	"struct already_linked *" in _section_already_linked.
	* bfd-in2.h: Regenerate.
	* libbfd.h: Regenerate.

include/
	* bfdlink.h (bfd_link_info): Add loading_lto_outputs.

ld/
	* ldlang.c (section_already_linked): Pass "struct already_linked *"
	to bfd_section_already_linked.
	(lang_process): Set link_info.loading_lto_outputs before
	loading LTO outputs.
	* plugin.c: Include "libbfd.h".
	(add_symbols): Call bfd_section_already_linked with comdat_key.