(class Initialize_lock): Rewrite as child of Once.
* gold-threads.cc (class Once_initialize): Define.
(once_pointer_control): New static variable.
(once_pointer, once_arg): New static variables.
(c_run_once): New static function.
(Once::Once, Once::run_once, Once::internal_run): New functions.
(class Initialize_lock_once): Remove.
(initialize_lock_control): Remove.
(initialize_lock_pointer): Remove.
(initialize_lock_once): Remove.
(Initialize_lock::Initialize_lock): Move to gold-threads.h.
(Initialize_lock::initialize): Rewrite.
(Initialize_lock::do_run_once): New function.
* archive.cc (Archive::interpret_header): Only clear name if it is
not already empty.
* fileread.cc: Include "gold-threads.h"
(file_counts_lock): New static variable.
(file_counts_initialize_lock): Likewise.
(File_read::release): Only increment counts when using --stats.
Use a lock around the increment.
* parameters.cc (class Set_parameters_target_once): Define.
(set_parameters_target_once): New static variable.
(Parameters::Parameters): Move here from parameters.h.
(Parameters::set_target): Rewrite.
(Parameters::set_target_once): New function.
(Parameters::clear_target): Move here and rewrite.
* parameters.h (class Parameters): Update declarations. Add
set_parameters_target_once_ field.
(Parameters::Parameters): Move to parameters.cc.
(Parameters::clear_target): Likewise.
* readsyms.cc (Read_symbols::do_group): Create a Start_group
task.
(Start_group::~Start_group): New function.
(Start_group::is_runnable): New function.
(Start_group::locks, Start_group::run): New functions.
(Finish_group::run): Change saw_undefined to size_t.
* readsyms.h (class Start_group): Define.
(class Finish_group): Change saw_undefined_ field to size_t.
(Finish_group::Finish_group): Remove saw_undefined and
this_blocker parameters. Change all callers.
(Finish_group::set_saw_undefined): New function.
(Finish_group::set_blocker): New function.
* symtab.h (class Symbol_table): Change saw_undefined to return
size_t. Change saw_undefined_ field to size_t.
* target-select.cc (Set_target_once::do_run_once): New function.
(Target_selector::Target_selector): Initialize set_target_once_
field. Don't initialize lock_ and initialize_lock_ fields.
(Target_selector::instantiate_target): Rewrite.
(Target_selector::set_target): New function.
* target-select.h (class Set_target_once): Define.
(class Target_selector): Update declarations. Make
Set_target_once a friend. Remove lock_ and initialize_lock_
fields. Add set_target_once_ field.
(Read_symbols::requeue): New function.
(Read_symbols::do_read_symbols): If make_elf_object fails because
the target type is not configured, and the file was searched for,
issue a warning and retry with the next directory.
(Add_symbols::run): If the file has an incompatible format, and
it was searched for, requeue the Read_symbols task. On error,
release the object.
* readsyms.h (class Read_symbols): Add dirindex_ field. Add
dirindex parameter to constructor. Change all callers. Declare
incompatible_warning and requeue.
(class Add_symbols): Add dirpath_, dirindex_, mapfile_,
input_argument_ and input_group_ fields. Add them to
constructor. Change all callers.
(class Read_script): Add dirindex_ field. Add it to constructor.
Change all callers.
* archive.cc (Archive::setup): Remove input_objects parameter.
Change all callers.
(Archive::get_file_and_offset): Likewise.
(Archive::read_all_symbols): Likewise.
(Archive::read_symbols): Likewise.
(Archive::get_elf_object_for_member): Remove input_objects
parameter. Add punconfigured parameter. Change all callers.
(Archive::add_symbols): Change return type to bool. Check return
value of include_member.
(Archive::include_all_members): Likewise.
(Archive::include_member): Change return type to bool. Return
false if first included object has incompatible target. Set
included_member_ field.
(Add_archive_symbols::run): If add_symbols returns false, requeue
Read_symbols task.
* archive.h (class Archive): Add included_member_ field.
Initialize it in constructor. Add input_file and searched_for
methods. Update declarations.
(class Add_archive_symbols): Add dirpath_, dirindex_, and
input_argument_ fields. Add them to constructor. Change all
callers.
* script.cc: Include "target-select.h".
(class Parser_closure): Add skip_on_incompatible_target_ and
found_incompatible_target_ fields. Add
skip_on_incompatible_target parameter to constructor. Change all
callers. Add methods skip_on_incompatible_target,
clear_skip_on_incompatible_target, found_incompatible_target, and
set_found_incompatible_target.
(read_input_script): Add dirindex parameter. Change all callers.
If parser finds an incompatible target, requeue Read_symbols
task.
(script_set_symbol): Clear skip_on_incompatible_target in
closure.
(script_add_assertion, script_parse_option): Likewise.
(script_start_sections, script_add_phdr): Likewise.
(script_check_output_format): New function.
* script.h (read_input_script): Update declaration.
* script-c.h (script_check_output_format): Declare.
* yyscript.y (file_cmd): Handle OUTPUT_FORMAT.
(ignore_cmd): Remove OUTPUT_FORMAT.
* fileread.cc (Input_file::Input_file): Add explicit this.
(Input_file::will_search_for): New function.
(Input_file::open): Add pindex parameter. Change all callers.
* fileread.h (class Input_file): Add input_file_argument method.
Declare will_search_for. Update declarations.
* object.cc (make_elf_object): Add punconfigured parameter.
Change all callers.
* object.h (class Object): Make input_file public. Add
searched_for method.
(make_elf_object): Update declaration.
* dirsearch.cc (Dirsearch::find): Add pindex parameter. Use it to
restart search.
* dirsearch.h (class Dirsearch): Update declaration.
* options.h (class General_options): Add --warn-search-mismatch.
* parameters.cc (Parameters::is_compatible_target): New function.
* parameters.h (class Parameters): Declare is_compatible_target.
* workqueue.cc (Workqueue::add_blocker): New function.
* workqueue.h (class Workqueue): Declare add_blocker.
