894 lines
29 KiB
C++
894 lines
29 KiB
C++
// gold.cc -- main linker functions
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// Copyright (C) 2006-2015 Free Software Foundation, Inc.
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// Written by Ian Lance Taylor <iant@google.com>.
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// This file is part of gold.
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 3 of the License, or
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// (at your option) any later version.
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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// MA 02110-1301, USA.
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#include "gold.h"
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#include <cstdlib>
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#include <cstdio>
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#include <cstring>
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#include <unistd.h>
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#include <algorithm>
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#include "libiberty.h"
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#include "options.h"
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#include "target-select.h"
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#include "debug.h"
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#include "workqueue.h"
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#include "dirsearch.h"
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#include "readsyms.h"
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#include "symtab.h"
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#include "common.h"
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#include "object.h"
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#include "layout.h"
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#include "reloc.h"
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#include "defstd.h"
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#include "plugin.h"
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#include "gc.h"
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#include "icf.h"
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#include "incremental.h"
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#include "timer.h"
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namespace gold
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{
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class Object;
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const char* program_name;
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static Task*
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process_incremental_input(Incremental_binary*, unsigned int, Input_objects*,
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Symbol_table*, Layout*, Dirsearch*, Mapfile*,
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Task_token*, Task_token*);
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void
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gold_exit(Exit_status status)
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{
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if (parameters != NULL
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&& parameters->options_valid()
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&& parameters->options().has_plugins())
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parameters->options().plugins()->cleanup();
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if (status != GOLD_OK && parameters != NULL && parameters->options_valid())
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unlink_if_ordinary(parameters->options().output_file_name());
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exit(status);
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}
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void
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gold_nomem()
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{
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// We are out of memory, so try hard to print a reasonable message.
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// Note that we don't try to translate this message, since the
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// translation process itself will require memory.
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// LEN only exists to avoid a pointless warning when write is
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// declared with warn_use_result, as when compiling with
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// -D_USE_FORTIFY on GNU/Linux. Casting to void does not appear to
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// work, at least not with gcc 4.3.0.
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ssize_t len = write(2, program_name, strlen(program_name));
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if (len >= 0)
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{
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const char* const s = ": out of memory\n";
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len = write(2, s, strlen(s));
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}
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gold_exit(GOLD_ERR);
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}
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// Handle an unreachable case.
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void
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do_gold_unreachable(const char* filename, int lineno, const char* function)
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{
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fprintf(stderr, _("%s: internal error in %s, at %s:%d\n"),
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program_name, function, filename, lineno);
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gold_exit(GOLD_ERR);
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}
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// This class arranges to run the functions done in the middle of the
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// link. It is just a closure.
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class Middle_runner : public Task_function_runner
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{
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public:
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Middle_runner(const General_options& options,
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const Input_objects* input_objects,
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Symbol_table* symtab,
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Layout* layout, Mapfile* mapfile)
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: options_(options), input_objects_(input_objects), symtab_(symtab),
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layout_(layout), mapfile_(mapfile)
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{ }
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void
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run(Workqueue*, const Task*);
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private:
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const General_options& options_;
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const Input_objects* input_objects_;
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Symbol_table* symtab_;
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Layout* layout_;
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Mapfile* mapfile_;
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};
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void
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Middle_runner::run(Workqueue* workqueue, const Task* task)
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{
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queue_middle_tasks(this->options_, task, this->input_objects_, this->symtab_,
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this->layout_, workqueue, this->mapfile_);
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}
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// This class arranges the tasks to process the relocs for garbage collection.
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class Gc_runner : public Task_function_runner
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{
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public:
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Gc_runner(const General_options& options,
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const Input_objects* input_objects,
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Symbol_table* symtab,
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Layout* layout, Mapfile* mapfile)
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: options_(options), input_objects_(input_objects), symtab_(symtab),
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layout_(layout), mapfile_(mapfile)
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{ }
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void
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run(Workqueue*, const Task*);
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private:
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const General_options& options_;
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const Input_objects* input_objects_;
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Symbol_table* symtab_;
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Layout* layout_;
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Mapfile* mapfile_;
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};
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void
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Gc_runner::run(Workqueue* workqueue, const Task* task)
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{
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queue_middle_gc_tasks(this->options_, task, this->input_objects_,
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this->symtab_, this->layout_, workqueue,
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this->mapfile_);
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}
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// Queue up the initial set of tasks for this link job.
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void
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queue_initial_tasks(const General_options& options,
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Dirsearch& search_path,
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const Command_line& cmdline,
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Workqueue* workqueue, Input_objects* input_objects,
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Symbol_table* symtab, Layout* layout, Mapfile* mapfile)
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{
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if (cmdline.begin() == cmdline.end())
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{
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bool is_ok = false;
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if (options.printed_version())
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is_ok = true;
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if (options.print_output_format())
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{
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print_output_format();
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is_ok = true;
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}
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if (is_ok)
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gold_exit(GOLD_OK);
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gold_fatal(_("no input files"));
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}
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int thread_count = options.thread_count_initial();
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if (thread_count == 0)
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thread_count = cmdline.number_of_input_files();
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workqueue->set_thread_count(thread_count);
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// For incremental links, the base output file.
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Incremental_binary* ibase = NULL;
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if (parameters->incremental_update())
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{
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Output_file* of = new Output_file(options.output_file_name());
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if (of->open_base_file(options.incremental_base(), true))
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{
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ibase = open_incremental_binary(of);
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if (ibase != NULL
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&& ibase->check_inputs(cmdline, layout->incremental_inputs()))
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ibase->init_layout(layout);
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else
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{
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delete ibase;
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ibase = NULL;
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of->close();
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}
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}
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if (ibase == NULL)
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{
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if (set_parameters_incremental_full())
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gold_info(_("linking with --incremental-full"));
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else
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gold_fallback(_("restart link with --incremental-full"));
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}
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}
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// Read the input files. We have to add the symbols to the symbol
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// table in order. We do this by creating a separate blocker for
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// each input file. We associate the blocker with the following
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// input file, to give us a convenient place to delete it.
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Task_token* this_blocker = NULL;
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if (ibase == NULL)
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{
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// Normal link. Queue a Read_symbols task for each input file
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// on the command line.
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for (Command_line::const_iterator p = cmdline.begin();
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p != cmdline.end();
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++p)
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{
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Task_token* next_blocker = new Task_token(true);
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next_blocker->add_blocker();
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workqueue->queue(new Read_symbols(input_objects, symtab, layout,
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&search_path, 0, mapfile, &*p, NULL,
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NULL, this_blocker, next_blocker));
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this_blocker = next_blocker;
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}
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}
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else
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{
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// Incremental update link. Process the list of input files
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// stored in the base file, and queue a task for each file:
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// a Read_symbols task for a changed file, and an Add_symbols task
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// for an unchanged file. We need to mark all the space used by
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// unchanged files before we can start any tasks running.
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unsigned int input_file_count = ibase->input_file_count();
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std::vector<Task*> tasks;
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tasks.reserve(input_file_count);
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for (unsigned int i = 0; i < input_file_count; ++i)
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{
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Task_token* next_blocker = new Task_token(true);
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next_blocker->add_blocker();
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Task* t = process_incremental_input(ibase, i, input_objects, symtab,
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layout, &search_path, mapfile,
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this_blocker, next_blocker);
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tasks.push_back(t);
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this_blocker = next_blocker;
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}
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// Now we can queue the tasks.
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for (unsigned int i = 0; i < tasks.size(); i++)
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workqueue->queue(tasks[i]);
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}
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if (options.has_plugins())
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{
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Task_token* next_blocker = new Task_token(true);
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next_blocker->add_blocker();
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workqueue->queue(new Plugin_hook(options, input_objects, symtab, layout,
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&search_path, mapfile, this_blocker,
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next_blocker));
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this_blocker = next_blocker;
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}
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if (options.relocatable()
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&& (options.gc_sections() || options.icf_enabled()))
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gold_error(_("cannot mix -r with --gc-sections or --icf"));
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if (options.gc_sections() || options.icf_enabled())
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{
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workqueue->queue(new Task_function(new Gc_runner(options,
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input_objects,
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symtab,
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layout,
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mapfile),
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this_blocker,
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"Task_function Gc_runner"));
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}
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else
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{
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workqueue->queue(new Task_function(new Middle_runner(options,
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input_objects,
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symtab,
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layout,
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mapfile),
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this_blocker,
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"Task_function Middle_runner"));
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}
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}
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// Process an incremental input file: if it is unchanged from the previous
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// link, return a task to add its symbols from the base file's incremental
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// info; if it has changed, return a normal Read_symbols task. We create a
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// task for every input file, if only to report the file for rebuilding the
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// incremental info.
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static Task*
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process_incremental_input(Incremental_binary* ibase,
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unsigned int input_file_index,
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Input_objects* input_objects,
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Symbol_table* symtab,
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Layout* layout,
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Dirsearch* search_path,
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Mapfile* mapfile,
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Task_token* this_blocker,
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Task_token* next_blocker)
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{
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const Incremental_binary::Input_reader* input_reader =
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ibase->get_input_reader(input_file_index);
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Incremental_input_type input_type = input_reader->type();
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// Get the input argument corresponding to this input file, matching on
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// the argument serial number. If the input file cannot be matched
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// to an existing input argument, synthesize a new one.
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const Input_argument* input_argument =
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ibase->get_input_argument(input_file_index);
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if (input_argument == NULL)
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{
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Input_file_argument file(input_reader->filename(),
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Input_file_argument::INPUT_FILE_TYPE_FILE,
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"", false, parameters->options());
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Input_argument* arg = new Input_argument(file);
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arg->set_script_info(ibase->get_script_info(input_file_index));
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input_argument = arg;
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}
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gold_debug(DEBUG_INCREMENTAL, "Incremental object: %s, type %d",
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input_reader->filename(), input_type);
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if (input_type == INCREMENTAL_INPUT_SCRIPT)
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{
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// Incremental_binary::check_inputs should have cancelled the
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// incremental update if the script has changed.
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gold_assert(!ibase->file_has_changed(input_file_index));
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return new Check_script(layout, ibase, input_file_index, input_reader,
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this_blocker, next_blocker);
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}
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if (input_type == INCREMENTAL_INPUT_ARCHIVE)
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{
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Incremental_library* lib = ibase->get_library(input_file_index);
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gold_assert(lib != NULL);
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if (lib->filename() == "/group/"
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|| !ibase->file_has_changed(input_file_index))
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{
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// Queue a task to check that no references have been added to any
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// of the library's unused symbols.
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return new Check_library(symtab, layout, ibase, input_file_index,
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input_reader, this_blocker, next_blocker);
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}
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else
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{
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// Queue a Read_symbols task to process the archive normally.
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return new Read_symbols(input_objects, symtab, layout, search_path,
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0, mapfile, input_argument, NULL, NULL,
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this_blocker, next_blocker);
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}
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}
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if (input_type == INCREMENTAL_INPUT_ARCHIVE_MEMBER)
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{
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// For archive members, check the timestamp of the containing archive.
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Incremental_library* lib = ibase->get_library(input_file_index);
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gold_assert(lib != NULL);
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// Process members of a --start-lib/--end-lib group as normal objects.
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if (lib->filename() != "/group/")
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{
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if (ibase->file_has_changed(lib->input_file_index()))
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{
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return new Read_member(input_objects, symtab, layout, mapfile,
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input_reader, this_blocker, next_blocker);
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}
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else
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{
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// The previous contributions from this file will be kept.
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// Mark the pieces of output sections contributed by this
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// object.
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ibase->reserve_layout(input_file_index);
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Object* obj = make_sized_incremental_object(ibase,
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input_file_index,
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input_type,
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input_reader);
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return new Add_symbols(input_objects, symtab, layout,
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search_path, 0, mapfile, input_argument,
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obj, lib, NULL, this_blocker,
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next_blocker);
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}
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}
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}
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// Normal object file or shared library. Check if the file has changed
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// since the last incremental link.
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if (ibase->file_has_changed(input_file_index))
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{
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return new Read_symbols(input_objects, symtab, layout, search_path, 0,
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mapfile, input_argument, NULL, NULL,
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this_blocker, next_blocker);
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}
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else
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{
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// The previous contributions from this file will be kept.
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// Mark the pieces of output sections contributed by this object.
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ibase->reserve_layout(input_file_index);
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Object* obj = make_sized_incremental_object(ibase,
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input_file_index,
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input_type,
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input_reader);
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return new Add_symbols(input_objects, symtab, layout, search_path, 0,
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mapfile, input_argument, obj, NULL, NULL,
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this_blocker, next_blocker);
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}
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}
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// Queue up a set of tasks to be done before queueing the middle set
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// of tasks. This is only necessary when garbage collection
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// (--gc-sections) of unused sections is desired. The relocs are read
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// and processed here early to determine the garbage sections before the
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// relocs can be scanned in later tasks.
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void
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queue_middle_gc_tasks(const General_options& options,
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const Task* ,
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const Input_objects* input_objects,
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Symbol_table* symtab,
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Layout* layout,
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Workqueue* workqueue,
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Mapfile* mapfile)
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{
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// Read_relocs for all the objects must be done and processed to find
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// unused sections before any scanning of the relocs can take place.
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Task_token* this_blocker = NULL;
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for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
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p != input_objects->relobj_end();
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++p)
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{
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Task_token* next_blocker = new Task_token(true);
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next_blocker->add_blocker();
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workqueue->queue(new Read_relocs(symtab, layout, *p, this_blocker,
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next_blocker));
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this_blocker = next_blocker;
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}
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// If we are given only archives in input, we have no regular
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// objects and THIS_BLOCKER is NULL here. Create a dummy
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// blocker here so that we can run the middle tasks immediately.
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if (this_blocker == NULL)
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{
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gold_assert(input_objects->number_of_relobjs() == 0);
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this_blocker = new Task_token(true);
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}
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workqueue->queue(new Task_function(new Middle_runner(options,
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input_objects,
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symtab,
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layout,
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mapfile),
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this_blocker,
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"Task_function Middle_runner"));
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}
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// Queue up the middle set of tasks. These are the tasks which run
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// after all the input objects have been found and all the symbols
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// have been read, but before we lay out the output file.
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void
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queue_middle_tasks(const General_options& options,
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const Task* task,
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const Input_objects* input_objects,
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Symbol_table* symtab,
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Layout* layout,
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Workqueue* workqueue,
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Mapfile* mapfile)
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{
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Timer* timer = parameters->timer();
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if (timer != NULL)
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timer->stamp(0);
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// Finalize the .eh_frame section.
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layout->finalize_eh_frame_section();
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// Add any symbols named with -u options to the symbol table.
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symtab->add_undefined_symbols_from_command_line(layout);
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// If garbage collection was chosen, relocs have been read and processed
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// at this point by pre_middle_tasks. Layout can then be done for all
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// objects.
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if (parameters->options().gc_sections())
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{
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// Find the start symbol if any.
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Symbol* sym = symtab->lookup(parameters->entry());
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if (sym != NULL)
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symtab->gc_mark_symbol(sym);
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sym = symtab->lookup(parameters->options().init());
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if (sym != NULL && sym->is_defined() && !sym->is_from_dynobj())
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symtab->gc_mark_symbol(sym);
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sym = symtab->lookup(parameters->options().fini());
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if (sym != NULL && sym->is_defined() && !sym->is_from_dynobj())
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symtab->gc_mark_symbol(sym);
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// Symbols named with -u should not be considered garbage.
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symtab->gc_mark_undef_symbols(layout);
|
|
gold_assert(symtab->gc() != NULL);
|
|
// Do a transitive closure on all references to determine the worklist.
|
|
symtab->gc()->do_transitive_closure();
|
|
}
|
|
|
|
// If identical code folding (--icf) is chosen it makes sense to do it
|
|
// only after garbage collection (--gc-sections) as we do not want to
|
|
// be folding sections that will be garbage.
|
|
if (parameters->options().icf_enabled())
|
|
{
|
|
symtab->icf()->find_identical_sections(input_objects, symtab);
|
|
}
|
|
|
|
// Call Object::layout for the second time to determine the
|
|
// output_sections for all referenced input sections. When
|
|
// --gc-sections or --icf is turned on, or when certain input
|
|
// sections have to be mapped to unique segments, Object::layout
|
|
// is called twice. It is called the first time when symbols
|
|
// are added.
|
|
if (parameters->options().gc_sections()
|
|
|| parameters->options().icf_enabled()
|
|
|| layout->is_unique_segment_for_sections_specified())
|
|
{
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
Task_lock_obj<Object> tlo(task, *p);
|
|
(*p)->layout(symtab, layout, NULL);
|
|
}
|
|
}
|
|
|
|
// Layout deferred objects due to plugins.
|
|
if (parameters->options().has_plugins())
|
|
{
|
|
Plugin_manager* plugins = parameters->options().plugins();
|
|
gold_assert(plugins != NULL);
|
|
plugins->layout_deferred_objects();
|
|
}
|
|
|
|
/* If plugins have specified a section order, re-arrange input sections
|
|
according to a specified section order. If --section-ordering-file is
|
|
also specified, do not do anything here. */
|
|
if (parameters->options().has_plugins()
|
|
&& layout->is_section_ordering_specified()
|
|
&& !parameters->options().section_ordering_file ())
|
|
{
|
|
for (Layout::Section_list::const_iterator p
|
|
= layout->section_list().begin();
|
|
p != layout->section_list().end();
|
|
++p)
|
|
(*p)->update_section_layout(layout->get_section_order_map());
|
|
}
|
|
|
|
if (parameters->options().gc_sections()
|
|
|| parameters->options().icf_enabled())
|
|
{
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
// Update the value of output_section stored in rd.
|
|
Read_relocs_data* rd = (*p)->get_relocs_data();
|
|
for (Read_relocs_data::Relocs_list::iterator q = rd->relocs.begin();
|
|
q != rd->relocs.end();
|
|
++q)
|
|
{
|
|
q->output_section = (*p)->output_section(q->data_shndx);
|
|
q->needs_special_offset_handling =
|
|
(*p)->is_output_section_offset_invalid(q->data_shndx);
|
|
}
|
|
}
|
|
}
|
|
|
|
// We have to support the case of not seeing any input objects, and
|
|
// generate an empty file. Existing builds depend on being able to
|
|
// pass an empty archive to the linker and get an empty object file
|
|
// out. In order to do this we need to use a default target.
|
|
if (input_objects->number_of_input_objects() == 0
|
|
&& layout->incremental_base() == NULL)
|
|
parameters_force_valid_target();
|
|
|
|
int thread_count = options.thread_count_middle();
|
|
if (thread_count == 0)
|
|
thread_count = std::max(2, input_objects->number_of_input_objects());
|
|
workqueue->set_thread_count(thread_count);
|
|
|
|
// Now we have seen all the input files.
|
|
const bool doing_static_link =
|
|
(!input_objects->any_dynamic()
|
|
&& !parameters->options().output_is_position_independent());
|
|
set_parameters_doing_static_link(doing_static_link);
|
|
if (!doing_static_link && options.is_static())
|
|
{
|
|
// We print out just the first .so we see; there may be others.
|
|
gold_assert(input_objects->dynobj_begin() != input_objects->dynobj_end());
|
|
gold_error(_("cannot mix -static with dynamic object %s"),
|
|
(*input_objects->dynobj_begin())->name().c_str());
|
|
}
|
|
if (!doing_static_link && parameters->options().relocatable())
|
|
gold_fatal(_("cannot mix -r with dynamic object %s"),
|
|
(*input_objects->dynobj_begin())->name().c_str());
|
|
if (!doing_static_link
|
|
&& options.oformat_enum() != General_options::OBJECT_FORMAT_ELF)
|
|
gold_fatal(_("cannot use non-ELF output format with dynamic object %s"),
|
|
(*input_objects->dynobj_begin())->name().c_str());
|
|
|
|
if (parameters->options().relocatable())
|
|
{
|
|
Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
if (p != input_objects->relobj_end())
|
|
{
|
|
bool uses_split_stack = (*p)->uses_split_stack();
|
|
for (++p; p != input_objects->relobj_end(); ++p)
|
|
{
|
|
if ((*p)->uses_split_stack() != uses_split_stack)
|
|
gold_fatal(_("cannot mix split-stack '%s' and "
|
|
"non-split-stack '%s' when using -r"),
|
|
(*input_objects->relobj_begin())->name().c_str(),
|
|
(*p)->name().c_str());
|
|
}
|
|
}
|
|
}
|
|
|
|
// For incremental updates, record the existing GOT and PLT entries,
|
|
// and the COPY relocations.
|
|
if (parameters->incremental_update())
|
|
{
|
|
Incremental_binary* ibase = layout->incremental_base();
|
|
ibase->process_got_plt(symtab, layout);
|
|
ibase->emit_copy_relocs(symtab);
|
|
}
|
|
|
|
if (is_debugging_enabled(DEBUG_SCRIPT))
|
|
layout->script_options()->print(stderr);
|
|
|
|
// For each dynamic object, record whether we've seen all the
|
|
// dynamic objects that it depends upon.
|
|
input_objects->check_dynamic_dependencies();
|
|
|
|
// Do the --no-undefined-version check.
|
|
if (!parameters->options().undefined_version())
|
|
{
|
|
Script_options* so = layout->script_options();
|
|
so->version_script_info()->check_unmatched_names(symtab);
|
|
}
|
|
|
|
// Create any automatic note sections.
|
|
layout->create_notes();
|
|
|
|
// Create any output sections required by any linker script.
|
|
layout->create_script_sections();
|
|
|
|
// Define some sections and symbols needed for a dynamic link. This
|
|
// handles some cases we want to see before we read the relocs.
|
|
layout->create_initial_dynamic_sections(symtab);
|
|
|
|
// Define symbols from any linker scripts.
|
|
layout->define_script_symbols(symtab);
|
|
|
|
// TODO(csilvers): figure out a more principled way to get the target
|
|
Target* target = const_cast<Target*>(¶meters->target());
|
|
|
|
// Attach sections to segments.
|
|
layout->attach_sections_to_segments(target);
|
|
|
|
if (!parameters->options().relocatable())
|
|
{
|
|
// Predefine standard symbols.
|
|
define_standard_symbols(symtab, layout);
|
|
|
|
// Define __start and __stop symbols for output sections where
|
|
// appropriate.
|
|
layout->define_section_symbols(symtab);
|
|
|
|
// Define target-specific symbols.
|
|
target->define_standard_symbols(symtab, layout);
|
|
}
|
|
|
|
// Make sure we have symbols for any required group signatures.
|
|
layout->define_group_signatures(symtab);
|
|
|
|
Task_token* this_blocker = NULL;
|
|
|
|
// Allocate common symbols. We use a blocker to run this before the
|
|
// Scan_relocs tasks, because it writes to the symbol table just as
|
|
// they do.
|
|
if (parameters->options().define_common())
|
|
{
|
|
this_blocker = new Task_token(true);
|
|
this_blocker->add_blocker();
|
|
workqueue->queue(new Allocate_commons_task(symtab, layout, mapfile,
|
|
this_blocker));
|
|
}
|
|
|
|
// If doing garbage collection, the relocations have already been read.
|
|
// Otherwise, read and scan the relocations.
|
|
if (parameters->options().gc_sections()
|
|
|| parameters->options().icf_enabled())
|
|
{
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
Task_token* next_blocker = new Task_token(true);
|
|
next_blocker->add_blocker();
|
|
workqueue->queue(new Scan_relocs(symtab, layout, *p,
|
|
(*p)->get_relocs_data(),
|
|
this_blocker, next_blocker));
|
|
this_blocker = next_blocker;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// Read the relocations of the input files. We do this to find
|
|
// which symbols are used by relocations which require a GOT and/or
|
|
// a PLT entry, or a COPY reloc. When we implement garbage
|
|
// collection we will do it here by reading the relocations in a
|
|
// breadth first search by references.
|
|
//
|
|
// We could also read the relocations during the first pass, and
|
|
// mark symbols at that time. That is how the old GNU linker works.
|
|
// Doing that is more complex, since we may later decide to discard
|
|
// some of the sections, and thus change our minds about the types
|
|
// of references made to the symbols.
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
{
|
|
Task_token* next_blocker = new Task_token(true);
|
|
next_blocker->add_blocker();
|
|
workqueue->queue(new Read_relocs(symtab, layout, *p, this_blocker,
|
|
next_blocker));
|
|
this_blocker = next_blocker;
|
|
}
|
|
}
|
|
|
|
if (this_blocker == NULL)
|
|
{
|
|
if (input_objects->number_of_relobjs() == 0)
|
|
{
|
|
// If we are given only archives in input, we have no regular
|
|
// objects and THIS_BLOCKER is NULL here. Create a dummy
|
|
// blocker here so that we can run the layout task immediately.
|
|
this_blocker = new Task_token(true);
|
|
}
|
|
else
|
|
{
|
|
// If we failed to open any input files, it's possible for
|
|
// THIS_BLOCKER to be NULL here. There's no real point in
|
|
// continuing if that happens.
|
|
gold_assert(parameters->errors()->error_count() > 0);
|
|
gold_exit(GOLD_ERR);
|
|
}
|
|
}
|
|
|
|
// When all those tasks are complete, we can start laying out the
|
|
// output file.
|
|
workqueue->queue(new Task_function(new Layout_task_runner(options,
|
|
input_objects,
|
|
symtab,
|
|
target,
|
|
layout,
|
|
mapfile),
|
|
this_blocker,
|
|
"Task_function Layout_task_runner"));
|
|
}
|
|
|
|
// Queue up the final set of tasks. This is called at the end of
|
|
// Layout_task.
|
|
|
|
void
|
|
queue_final_tasks(const General_options& options,
|
|
const Input_objects* input_objects,
|
|
const Symbol_table* symtab,
|
|
Layout* layout,
|
|
Workqueue* workqueue,
|
|
Output_file* of)
|
|
{
|
|
Timer* timer = parameters->timer();
|
|
if (timer != NULL)
|
|
timer->stamp(1);
|
|
|
|
int thread_count = options.thread_count_final();
|
|
if (thread_count == 0)
|
|
thread_count = std::max(2, input_objects->number_of_input_objects());
|
|
workqueue->set_thread_count(thread_count);
|
|
|
|
bool any_postprocessing_sections = layout->any_postprocessing_sections();
|
|
|
|
// Use a blocker to wait until all the input sections have been
|
|
// written out.
|
|
Task_token* input_sections_blocker = NULL;
|
|
if (!any_postprocessing_sections)
|
|
{
|
|
input_sections_blocker = new Task_token(true);
|
|
// Write_symbols_task, Relocate_tasks.
|
|
input_sections_blocker->add_blocker();
|
|
input_sections_blocker->add_blockers(input_objects->number_of_relobjs());
|
|
}
|
|
|
|
// Use a blocker to block any objects which have to wait for the
|
|
// output sections to complete before they can apply relocations.
|
|
Task_token* output_sections_blocker = new Task_token(true);
|
|
output_sections_blocker->add_blocker();
|
|
|
|
// Use a blocker to block the final cleanup task.
|
|
Task_token* final_blocker = new Task_token(true);
|
|
// Write_symbols_task, Write_sections_task, Write_data_task,
|
|
// Relocate_tasks.
|
|
final_blocker->add_blockers(3);
|
|
final_blocker->add_blockers(input_objects->number_of_relobjs());
|
|
if (!any_postprocessing_sections)
|
|
final_blocker->add_blocker();
|
|
|
|
// Queue a task to write out the symbol table.
|
|
workqueue->queue(new Write_symbols_task(layout,
|
|
symtab,
|
|
input_objects,
|
|
layout->sympool(),
|
|
layout->dynpool(),
|
|
of,
|
|
final_blocker));
|
|
|
|
// Queue a task to write out the output sections.
|
|
workqueue->queue(new Write_sections_task(layout, of, output_sections_blocker,
|
|
input_sections_blocker,
|
|
final_blocker));
|
|
|
|
// Queue a task to write out everything else.
|
|
workqueue->queue(new Write_data_task(layout, symtab, of, final_blocker));
|
|
|
|
// Queue a task for each input object to relocate the sections and
|
|
// write out the local symbols.
|
|
for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
|
|
p != input_objects->relobj_end();
|
|
++p)
|
|
workqueue->queue(new Relocate_task(symtab, layout, *p, of,
|
|
input_sections_blocker,
|
|
output_sections_blocker,
|
|
final_blocker));
|
|
|
|
// Queue a task to write out the output sections which depend on
|
|
// input sections. If there are any sections which require
|
|
// postprocessing, then we need to do this last, since it may resize
|
|
// the output file.
|
|
if (!any_postprocessing_sections)
|
|
{
|
|
Task* t = new Write_after_input_sections_task(layout, of,
|
|
input_sections_blocker,
|
|
final_blocker);
|
|
workqueue->queue(t);
|
|
}
|
|
else
|
|
{
|
|
Task_token* new_final_blocker = new Task_token(true);
|
|
new_final_blocker->add_blocker();
|
|
Task* t = new Write_after_input_sections_task(layout, of,
|
|
final_blocker,
|
|
new_final_blocker);
|
|
workqueue->queue(t);
|
|
final_blocker = new_final_blocker;
|
|
}
|
|
|
|
// Create tasks for tree-style build ID computation, if necessary.
|
|
final_blocker = layout->queue_build_id_tasks(workqueue, final_blocker, of);
|
|
|
|
// Queue a task to close the output file. This will be blocked by
|
|
// FINAL_BLOCKER.
|
|
workqueue->queue(new Task_function(new Close_task_runner(&options, layout,
|
|
of),
|
|
final_blocker,
|
|
"Task_function Close_task_runner"));
|
|
}
|
|
|
|
} // End namespace gold.
|