Extensive changes to move the bulk of the linker into BFD so that

	Extensive changes to move the bulk of the linker into BFD so that
	more efficient backend code can be written for specific object
	files.  Only existing efficient backend is a.out.
	* seclet.c, seclet.h: Removed.
	* hash.c, linker.c, genlink.h: New files.
	* bfd-in.h: Removed bfd_error_vector.  Declared hash table
	structures and functions.
	(JUMP_TABLE): Removed bfd_seclet_link, added
	bfd_link_hash_table_create, bfd_link_add_symbols and
	bfd_final_link.
	* All backends: Changed accordingly.
	* bfd-in2.h: Rebuilt.
	* bfd.c (struct _bfd): Added link_next and archive_pass fields.
	Removed ld_symbols field.
	(bfd_nonrepresentable_section, bfd_undefined_symbol,
	bfd_reloc_value_truncated, bfd_reloc_is_dangerous,
	bfd_error_vector): Removed.
	(bfd_default_error_trap, bfd_error_trap,
	bfd_error_nonrepresentabltrap): Removed.
	(bfd_get_relocated_section_contents): Pass link_info.  Pass
	link_order instead of seclet.  Pass symbols.
	(bfd_relax_section): Pass link_info.
	(bfd_seclet_link): Removed.
	(bfd_link_hash_table_create, bfd_link_add_symbols,
	bfd_final_link): New macros.
	* libbfd-in.h: If __GNUC__ is defined and alloca is not, define
	alloca as __builtin_alloca.  Declare internal linking functions.
	* libbfd.h: Rebuilt.
	* libbfd.c (bfd_seek): Comment out fseek assertion.  It's worked
	for months.
	* reloc.c (reloc_howto_type): Added error_message argument to
	special_function field.  Changed all callers and all definitions.
	(bfd_get_reloc_size): Make argument a const pointer.
	(bfd_perform_relocation): Add error_message argument to hold
	string set if return value if bfd_reloc_dangerous.  Changed all
	callers.
	(_bfd_final_link_relocate, _bfd_relocate_contents): New functions.
	* section.c (asection): Renamed seclets_head and seclets_tail to
	link_order_head and link_order_tail.
	* targets.c (bfd_target): Replaced seclet argument with link_info
	and link_order and symbols arguments in
	bfd_get_relocated_section_contents.  Added symbols argument to
	bfd_relax_section.  Removed bfd_seclet_link.  Added
	bfd_link_hash_table_create, bfd_link_add_symbols and
	bfd_final_link.
	* libaout.h (struct aoutdata): Added external_syms,
	external_sym_count, external_strings, sym_hashes fields.
	(obj_aout_external_syms, obj_aout_external_sym_count,
	obj_aout_external_strings, obj_aout_sym_hashes): New accessor
	macros.
	(WRITE_HEADERS): Only output symbols if outsymbols is not NULL.
	* aoutx.h: Wrote new back end linker routines.
	(translate_to_native_sym_flags): Return boolean value.  Don't use
	bfd_error_vector.
	(NAME(aout,write_syms)): Return boolean value.  Check return value
	of translate_to_native_sym_flags and bfd_write.
	* aout-target.h (final_link_callback): New function.
	(MY_bfd_final_link): New function.
	* aout-adobe.c (aout_adobe_write_object_contents): Check return
	value of aout_32_write_syms.
	* hp300hpux.c (MY(write_object_contents)): Likewise.
	* i386lynx.c (WRITE_HEADERS): Likewise.
	* libaout.h (WRITE_HEADERS): Likewise.
	* bout.c: Changed functions to use link_info->callbacks rather
	than bfd_error_vector, and link_orders rather than seclets.
	* coff-alpha.c: Likewise.
	* coff-h8300.c: Likewise.
	* coff-h8500.c: Likewise.
	* coff-sh.c: Likewise.
	* coff-z8k.c: Likewise.
	* elf32-hppa.c: Likewise.
	* reloc16.c: Likewise.
	* coff-alpha.c (alpha_ecoff_get_relocated_section_contents): Look
	up _gp in the hash table rather than in outsymbols.
	* coff-a29k.c (a29k_reloc): Pass errors back in new error_message
	argument rather than printing them.
	* coffcode.h (bfd_coff_reloc16_extra_cases): Take link_info and
	link_order arguments rather than seclet.  Changed all uses and
	definitions.
	(bfd_coff_reloc16_estimate): Pass link_info arguments.  Changed
	all uses and definitions.
	* libcoff.h: Rebuilt.
	* ecoff.c (ecoff_get_extr): If symbol is defined by linker, but
	not by ECOFF, make it scAbs.
	(ecoff_bfd_final_link): Renamed from ecoff_bfd_seclet_link and
	rewritten.
	* elf32-mips.c (mips_elf_final_link): Renamed from
	mips_elf_seclet_link and rewritten.
	* elf32-hppa.c (elf32_hppa_stub_description): Added link_info
	field.
	(new_stub, add_stub_by_name, hppa_elf_build_arg_reloc_stub,
	hppa_elf_build_long_branch_stub, hppa_look_for_stubs_in_section):
	Added link_info arguments.  Changed all callers.
	* elfcode.h (elf_slurp_symbol_table): Don't quit if outsymbols is
	not NULL.
	* oasys.c (oasys_write_sections): Return boolean value rather than
	using bfd_error_vector.
	(oasys_write_object_contents): Check return value of
	oasys_write_sections.
	* hosts/std-host.h: Don't declare qsort or strtol.
	* Makefile.in: Rebuild dependencies.
	(BFD_LIBS): Removed seclet.o.  Added hash.o and linker.o.
	(CFILES): Removed seclet.c.  Added hash.c and linker.c.
	(HFILES): Removed seclet.h.  Added genlink.h.