gold/readsyms.cc

   1 // readsyms.cc -- read input file symbols for gold
   2
   3 // Copyright (C) 2006-2018 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #include "gold.h"
  24
  25 #include <cstring>
  26
  27 #include "elfcpp.h"
  28 #include "options.h"
  29 #include "dirsearch.h"
  30 #include "symtab.h"
  31 #include "object.h"
  32 #include "archive.h"
  33 #include "script.h"
  34 #include "readsyms.h"
  35 #include "plugin.h"
  36 #include "layout.h"
  37 #include "incremental.h"
  38
  39 namespace gold
  40 {
  41
  42 // If we fail to open the object, then we won't create an Add_symbols
  43 // task.  However, we still need to unblock the token, or else the
  44 // link won't proceed to generate more error messages.  We can only
  45 // unblock tokens when the workqueue lock is held, so we need a dummy
  46 // task to do that.  The dummy task has to maintain the right sequence
  47 // of blocks, so we need both this_blocker and next_blocker.
  48
  49 class Unblock_token : public Task
  50 {
  51  public:
  52   Unblock_token(Task_token* this_blocker, Task_token* next_blocker)
  53     : this_blocker_(this_blocker), next_blocker_(next_blocker)
  54   { }
  55
  56   ~Unblock_token()
  57   {
  58     if (this->this_blocker_ != NULL)
  59       delete this->this_blocker_;
  60   }
  61
  62   Task_token*
  63   is_runnable()
  64   {
  65     if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
  66       return this->this_blocker_;
  67     return NULL;
  68   }
  69
  70   void
  71   locks(Task_locker* tl)
  72   { tl->add(this, this->next_blocker_); }
  73
  74   void
  75   run(Workqueue*)
  76   { }
  77
  78   std::string
  79   get_name() const
  80   { return "Unblock_token"; }
  81
  82  private:
  83   Task_token* this_blocker_;
  84   Task_token* next_blocker_;
  85 };
  86
  87 // Class read_symbols.
  88
  89 Read_symbols::~Read_symbols()
  90 {
  91   // The this_blocker_ and next_blocker_ pointers are passed on to the
  92   // Add_symbols task.
  93 }
  94
  95 // If appropriate, issue a warning about skipping an incompatible
  96 // file.
  97
  98 void
  99 Read_symbols::incompatible_warning(const Input_argument* input_argument,
 100                                    const Input_file* input_file)
 101 {
 102   if (parameters->options().warn_search_mismatch())
 103     gold_warning("skipping incompatible %s while searching for %s",
 104                  input_file->filename().c_str(),
 105                  input_argument->file().name());
 106 }
 107
 108 // Requeue a Read_symbols task to search for the next object with the
 109 // same name.
 110
 111 void
 112 Read_symbols::requeue(Workqueue* workqueue, Input_objects* input_objects,
 113                       Symbol_table* symtab, Layout* layout, Dirsearch* dirpath,
 114                       int dirindex, Mapfile* mapfile,
 115                       const Input_argument* input_argument,
 116                       Input_group* input_group, Task_token* next_blocker)
 117 {
 118   // Bump the directory search index.
 119   ++dirindex;
 120
 121   // We don't need to worry about this_blocker, since we already
 122   // reached it.  However, we are removing the blocker on next_blocker
 123   // because the calling task is completing.  So we need to add a new
 124   // blocker.  Since next_blocker may be shared by several tasks, we
 125   // need to increment the count with the workqueue lock held.
 126   workqueue->add_blocker(next_blocker);
 127
 128   workqueue->queue(new Read_symbols(input_objects, symtab, layout, dirpath,
 129                                     dirindex, mapfile, input_argument,
 130                                     input_group, NULL, NULL, next_blocker));
 131 }
 132
 133 // Return whether a Read_symbols task is runnable.  We can read an
 134 // ordinary input file immediately.  For an archive specified using
 135 // -l, we have to wait until the search path is complete.
 136
 137 Task_token*
 138 Read_symbols::is_runnable()
 139 {
 140   if (this->input_argument_->is_file()
 141       && this->input_argument_->file().may_need_search()
 142       && this->dirpath_->token()->is_blocked())
 143     return this->dirpath_->token();
 144
 145   return NULL;
 146 }
 147
 148 // Return a Task_locker for a Read_symbols task.  We don't need any
 149 // locks here.
 150
 151 void
 152 Read_symbols::locks(Task_locker* tl)
 153 {
 154   if (this->member_ != NULL)
 155     tl->add(this, this->next_blocker_);
 156 }
 157
 158 // Run a Read_symbols task.
 159
 160 void
 161 Read_symbols::run(Workqueue* workqueue)
 162 {
 163   // If we didn't queue a new task, then we need to explicitly unblock
 164   // the token. If the object is a member of a lib group, however,
 165   // the token was already added to the list of locks for the task,
 166   // and it will be unblocked automatically at the end of the task.
 167   if (!this->do_read_symbols(workqueue) && this->member_ == NULL)
 168     workqueue->queue_soon(new Unblock_token(this->this_blocker_,
 169                                             this->next_blocker_));
 170 }
 171
 172 // Handle a whole lib group. Other than collecting statistics, this just
 173 // mimics what we do for regular object files in the command line.
 174
 175 bool
 176 Read_symbols::do_whole_lib_group(Workqueue* workqueue)
 177 {
 178   const Input_file_lib* lib_group = this->input_argument_->lib();
 179
 180   ++Lib_group::total_lib_groups;
 181
 182   Task_token* this_blocker = this->this_blocker_;
 183   for (Input_file_lib::const_iterator i = lib_group->begin();
 184        i != lib_group->end();
 185        ++i)
 186     {
 187       ++Lib_group::total_members;
 188       ++Lib_group::total_members_loaded;
 189
 190       const Input_argument* arg = &*i;
 191
 192       Task_token* next_blocker;
 193       if (i != lib_group->end() - 1)
 194         {
 195           next_blocker = new Task_token(true);
 196           next_blocker->add_blocker();
 197         }
 198       else
 199         next_blocker = this->next_blocker_;
 200
 201       workqueue->queue_soon(new Read_symbols(this->input_objects_,
 202                                              this->symtab_, this->layout_,
 203                                              this->dirpath_, this->dirindex_,
 204                                              this->mapfile_, arg, NULL,
 205                                              NULL, this_blocker, next_blocker));
 206       this_blocker = next_blocker;
 207     }
 208
 209   return true;
 210 }
 211
 212 // Handle a lib group. We set Read_symbols Tasks as usual, but have them
 213 // just record the symbol data instead of adding the objects.  We also start
 214 // a Add_lib_group_symbols Task which runs after we've read all the symbols.
 215 // In that task we process the members in a loop until we are done.
 216
 217 bool
 218 Read_symbols::do_lib_group(Workqueue* workqueue)
 219 {
 220   const Input_file_lib* lib_group = this->input_argument_->lib();
 221
 222   if (lib_group->options().whole_archive())
 223     return this->do_whole_lib_group(workqueue);
 224
 225   Lib_group* lib = new Lib_group(lib_group, this);
 226
 227   Add_lib_group_symbols* add_lib_group_symbols =
 228     new Add_lib_group_symbols(this->symtab_, this->layout_,
 229                               this->input_objects_,
 230                               lib, this->next_blocker_);
 231
 232
 233   Task_token* next_blocker = new Task_token(true);
 234   int j = 0;
 235   for (Input_file_lib::const_iterator i = lib_group->begin();
 236        i != lib_group->end();
 237        ++i, ++j)
 238     {
 239       const Input_argument* arg = &*i;
 240       Archive_member* m = lib->get_member(j);
 241
 242       next_blocker->add_blocker();
 243
 244       // Since this Read_symbols will not create an Add_symbols,
 245       // just pass NULL as this_blocker.
 246       workqueue->queue_soon(new Read_symbols(this->input_objects_,
 247                                              this->symtab_, this->layout_,
 248                                              this->dirpath_, this->dirindex_,
 249                                              this->mapfile_, arg, NULL,
 250                                              m, NULL, next_blocker));
 251     }
 252
 253   add_lib_group_symbols->set_blocker(next_blocker, this->this_blocker_);
 254   workqueue->queue_soon(add_lib_group_symbols);
 255
 256   return true;
 257 }
 258
 259 // Open the file and read the symbols.  Return true if a new task was
 260 // queued, false if that could not happen due to some error.
 261
 262 bool
 263 Read_symbols::do_read_symbols(Workqueue* workqueue)
 264 {
 265   if (this->input_argument_->is_group())
 266     {
 267       gold_assert(this->input_group_ == NULL);
 268       this->do_group(workqueue);
 269       return true;
 270     }
 271
 272   if (this->input_argument_->is_lib())
 273     return this->do_lib_group(workqueue);
 274
 275   Input_file* input_file = new Input_file(&this->input_argument_->file());
 276   if (!input_file->open(*this->dirpath_, this, &this->dirindex_))
 277     return false;
 278
 279   // Read enough of the file to pick up the entire ELF header.
 280
 281   off_t filesize = input_file->file().filesize();
 282
 283   if (filesize == 0)
 284     {
 285       gold_error(_("%s: file is empty"),
 286                  input_file->file().filename().c_str());
 287       return false;
 288     }
 289
 290   const unsigned char* ehdr;
 291   int read_size;
 292   bool is_elf = is_elf_object(input_file, 0, &ehdr, &read_size);
 293
 294   if (read_size >= Archive::sarmag)
 295     {
 296       bool is_thin_archive
 297           = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0;
 298       if (is_thin_archive
 299           || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0)
 300         {
 301           // This is an archive.
 302           Archive* arch = new Archive(this->input_argument_->file().name(),
 303                                       input_file, is_thin_archive,
 304                                       this->dirpath_, this);
 305           arch->setup();
 306
 307           // Unlock the archive so it can be used in the next task.
 308           arch->unlock(this);
 309
 310           workqueue->queue_next(new Add_archive_symbols(this->symtab_,
 311                                                         this->layout_,
 312                                                         this->input_objects_,
 313                                                         this->dirpath_,
 314                                                         this->dirindex_,
 315                                                         this->mapfile_,
 316                                                         this->input_argument_,
 317                                                         arch,
 318                                                         this->input_group_,
 319                                                         this->this_blocker_,
 320                                                         this->next_blocker_));
 321           return true;
 322         }
 323     }
 324
 325   Object* elf_obj = NULL;
 326   bool unconfigured;
 327   bool* punconfigured = NULL;
 328   if (is_elf)
 329     {
 330       // This is an ELF object.
 331
 332       unconfigured = false;
 333       punconfigured = (input_file->will_search_for()
 334                        ? &unconfigured
 335                        : NULL);
 336       elf_obj = make_elf_object(input_file->filename(),
 337                                 input_file, 0, ehdr, read_size,
 338                                 punconfigured);
 339     }
 340
 341   if (parameters->options().has_plugins())
 342     {
 343       Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
 344                                                                    0, filesize,
 345                                                                    elf_obj);
 346       if (obj != NULL)
 347         {
 348           // Delete the elf_obj, this file has been claimed.
 349           if (elf_obj != NULL)
 350             delete elf_obj;
 351
 352           // The input file was claimed by a plugin, and its symbols
 353           // have been provided by the plugin.
 354
 355           // We are done with the file at this point, so unlock it.
 356           obj->unlock(this);
 357
 358           if (this->member_ != NULL)
 359             {
 360               this->member_->sd_ = NULL;
 361               this->member_->obj_ = obj;
 362               return true;
 363             }
 364
 365           workqueue->queue_next(new Add_symbols(this->input_objects_,
 366                                                 this->symtab_,
 367                                                 this->layout_,
 368                                                 this->dirpath_,
 369                                                 this->dirindex_,
 370                                                 this->mapfile_,
 371                                                 this->input_argument_,
 372                                                 obj,
 373                                                 NULL,
 374                                                 NULL,
 375                                                 this->this_blocker_,
 376                                                 this->next_blocker_));
 377           return true;
 378         }
 379     }
 380
 381   if (is_elf)
 382     {
 383       // This is an ELF object.
 384
 385       if (elf_obj == NULL)
 386         {
 387           if (unconfigured)
 388             {
 389               Read_symbols::incompatible_warning(this->input_argument_,
 390                                                  input_file);
 391               input_file->file().release();
 392               input_file->file().unlock(this);
 393               delete input_file;
 394               ++this->dirindex_;
 395               return this->do_read_symbols(workqueue);
 396             }
 397           return false;
 398         }
 399
 400       Read_symbols_data* sd = new Read_symbols_data;
 401       elf_obj->read_symbols(sd);
 402
 403       // Opening the file locked it, so now we need to unlock it.  We
 404       // need to unlock it before queuing the Add_symbols task,
 405       // because the workqueue doesn't know about our lock on the
 406       // file.  If we queue the Add_symbols task first, it will be
 407       // stuck on the end of the file lock, but since the workqueue
 408       // doesn't know about that lock, it will never release the
 409       // Add_symbols task.
 410
 411       input_file->file().unlock(this);
 412
 413       if (this->member_ != NULL)
 414         {
 415           this->member_->sd_ = sd;
 416           this->member_->obj_ = elf_obj;
 417           this->member_->arg_serial_ =
 418               this->input_argument_->file().arg_serial();
 419           return true;
 420         }
 421
 422       // We use queue_next because everything is cached for this
 423       // task to run right away if possible.
 424
 425       workqueue->queue_next(new Add_symbols(this->input_objects_,
 426                                             this->symtab_, this->layout_,
 427                                             this->dirpath_,
 428                                             this->dirindex_,
 429                                             this->mapfile_,
 430                                             this->input_argument_,
 431                                             elf_obj,
 432                                             NULL,
 433                                             sd,
 434                                             this->this_blocker_,
 435                                             this->next_blocker_));
 436
 437       return true;
 438     }
 439
 440   // Queue up a task to try to parse this file as a script.  We use a
 441   // separate task so that the script will be read in order with other
 442   // objects named on the command line.  Also so that we don't try to
 443   // read multiple scripts simultaneously, which could lead to
 444   // unpredictable changes to the General_options structure.
 445
 446   workqueue->queue_soon(new Read_script(this->symtab_,
 447                                         this->layout_,
 448                                         this->dirpath_,
 449                                         this->dirindex_,
 450                                         this->input_objects_,
 451                                         this->mapfile_,
 452                                         this->input_group_,
 453                                         this->input_argument_,
 454                                         input_file,
 455                                         this->this_blocker_,
 456                                         this->next_blocker_));
 457   return true;
 458 }
 459
 460 // Handle a group.  We need to walk through the arguments over and
 461 // over until we don't see any new undefined symbols.  We do this by
 462 // setting off Read_symbols Tasks as usual, but recording the archive
 463 // entries instead of deleting them.  We also start a Finish_group
 464 // Task which runs after we've read all the symbols.  In that task we
 465 // process the archives in a loop until we are done.
 466
 467 void
 468 Read_symbols::do_group(Workqueue* workqueue)
 469 {
 470   Input_group* input_group = new Input_group();
 471
 472   const Input_file_group* group = this->input_argument_->group();
 473   Task_token* this_blocker = this->this_blocker_;
 474
 475   Finish_group* finish_group = new Finish_group(this->input_objects_,
 476                                                 this->symtab_,
 477                                                 this->layout_,
 478                                                 this->mapfile_,
 479                                                 input_group,
 480                                                 this->next_blocker_);
 481
 482   Task_token* next_blocker = new Task_token(true);
 483   next_blocker->add_blocker();
 484   workqueue->queue_soon(new Start_group(this->symtab_, finish_group,
 485                                         this_blocker, next_blocker));
 486   this_blocker = next_blocker;
 487
 488   for (Input_file_group::const_iterator p = group->begin();
 489        p != group->end();
 490        ++p)
 491     {
 492       const Input_argument* arg = &*p;
 493       gold_assert(arg->is_file());
 494
 495       next_blocker = new Task_token(true);
 496       next_blocker->add_blocker();
 497       workqueue->queue_soon(new Read_symbols(this->input_objects_,
 498                                              this->symtab_, this->layout_,
 499                                              this->dirpath_, this->dirindex_,
 500                                              this->mapfile_, arg, input_group,
 501                                              NULL, this_blocker, next_blocker));
 502       this_blocker = next_blocker;
 503     }
 504
 505   finish_group->set_blocker(this_blocker);
 506
 507   workqueue->queue_soon(finish_group);
 508 }
 509
 510 // Return a debugging name for a Read_symbols task.
 511
 512 std::string
 513 Read_symbols::get_name() const
 514 {
 515   if (this->input_argument_->is_group())
 516     {
 517       std::string ret("Read_symbols group (");
 518       bool add_space = false;
 519       const Input_file_group* group = this->input_argument_->group();
 520       for (Input_file_group::const_iterator p = group->begin();
 521            p != group->end();
 522            ++p)
 523       {
 524         if (add_space)
 525           ret += ' ';
 526         ret += p->file().name();
 527         add_space = true;
 528       }
 529       return ret + ')';
 530     }
 531   else if (this->input_argument_->is_lib())
 532     {
 533       std::string ret("Read_symbols lib (");
 534       bool add_space = false;
 535       const Input_file_lib* lib = this->input_argument_->lib();
 536       for (Input_file_lib::const_iterator p = lib->begin();
 537            p != lib->end();
 538            ++p)
 539       {
 540         if (add_space)
 541           ret += ' ';
 542         ret += p->file().name();
 543         add_space = true;
 544       }
 545       return ret + ')';
 546     }
 547   else
 548     {
 549       std::string ret("Read_symbols ");
 550       if (this->input_argument_->file().is_lib())
 551         ret += "-l";
 552       else if (this->input_argument_->file().is_searched_file())
 553         ret += "-l:";
 554       ret += this->input_argument_->file().name();
 555       return ret;
 556     }
 557 }
 558
 559 // Class Add_symbols.
 560
 561 Add_symbols::~Add_symbols()
 562 {
 563   if (this->this_blocker_ != NULL)
 564     delete this->this_blocker_;
 565   // next_blocker_ is deleted by the task associated with the next
 566   // input file.
 567 }
 568
 569 // We are blocked by this_blocker_.  We block next_blocker_.  We also
 570 // lock the file.
 571
 572 Task_token*
 573 Add_symbols::is_runnable()
 574 {
 575   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 576     return this->this_blocker_;
 577   if (this->object_->is_locked())
 578     return this->object_->token();
 579   return NULL;
 580 }
 581
 582 void
 583 Add_symbols::locks(Task_locker* tl)
 584 {
 585   tl->add(this, this->next_blocker_);
 586   Task_token* token = this->object_->token();
 587   if (token != NULL)
 588     tl->add(this, token);
 589 }
 590
 591 // Add the symbols in the object to the symbol table.
 592
 593 void
 594 Add_symbols::run(Workqueue*)
 595 {
 596   Pluginobj* pluginobj = this->object_->pluginobj();
 597   if (pluginobj != NULL)
 598     {
 599       this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
 600       return;
 601     }
 602
 603   if (!this->input_objects_->add_object(this->object_))
 604     {
 605       this->object_->discard_decompressed_sections();
 606       gold_assert(this->sd_ != NULL);
 607       delete this->sd_;
 608       this->sd_ = NULL;
 609       this->object_->release();
 610       delete this->object_;
 611     }
 612   else
 613     {
 614       Incremental_inputs* incremental_inputs =
 615           this->layout_->incremental_inputs();
 616       if (incremental_inputs != NULL)
 617         {
 618           if (this->library_ != NULL && !this->library_->is_reported())
 619             {
 620               Incremental_binary* ibase = this->layout_->incremental_base();
 621               gold_assert(ibase != NULL);
 622               unsigned int lib_serial = this->library_->arg_serial();
 623               unsigned int lib_index = this->library_->input_file_index();
 624               Script_info* lib_script_info = ibase->get_script_info(lib_index);
 625               incremental_inputs->report_archive_begin(this->library_,
 626                                                        lib_serial,
 627                                                        lib_script_info);
 628             }
 629           unsigned int arg_serial = this->input_argument_->file().arg_serial();
 630           Script_info* script_info = this->input_argument_->script_info();
 631           incremental_inputs->report_object(this->object_, arg_serial,
 632                                             this->library_, script_info);
 633         }
 634       this->object_->layout(this->symtab_, this->layout_, this->sd_);
 635       this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
 636       this->object_->discard_decompressed_sections();
 637       delete this->sd_;
 638       this->sd_ = NULL;
 639       this->object_->release();
 640     }
 641 }
 642
 643 // Class Read_member.
 644
 645 Read_member::~Read_member()
 646 {
 647   if (this->this_blocker_ != NULL)
 648     delete this->this_blocker_;
 649   // next_blocker_ is deleted by the task associated with the next
 650   // input file.
 651 }
 652
 653 // Return whether a Read_member task is runnable.
 654
 655 Task_token*
 656 Read_member::is_runnable()
 657 {
 658   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 659     return this->this_blocker_;
 660   return NULL;
 661 }
 662
 663 void
 664 Read_member::locks(Task_locker* tl)
 665 {
 666   tl->add(this, this->next_blocker_);
 667 }
 668
 669 // Run a Read_member task.
 670
 671 void
 672 Read_member::run(Workqueue*)
 673 {
 674   // This task doesn't need to do anything for now.  The Read_symbols task
 675   // that is queued for the archive library will cause the archive to be
 676   // processed from scratch.
 677 }
 678
 679 // Class Check_script.
 680
 681 Check_script::~Check_script()
 682 {
 683   if (this->this_blocker_ != NULL)
 684     delete this->this_blocker_;
 685   // next_blocker_ is deleted by the task associated with the next
 686   // input file.
 687 }
 688
 689 // Return whether a Check_script task is runnable.
 690
 691 Task_token*
 692 Check_script::is_runnable()
 693 {
 694   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 695     return this->this_blocker_;
 696   return NULL;
 697 }
 698
 699 void
 700 Check_script::locks(Task_locker* tl)
 701 {
 702   tl->add(this, this->next_blocker_);
 703 }
 704
 705 // Run a Check_script task.
 706
 707 void
 708 Check_script::run(Workqueue*)
 709 {
 710   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
 711   gold_assert(incremental_inputs != NULL);
 712   unsigned int arg_serial = this->input_reader_->arg_serial();
 713   Script_info* script_info =
 714       this->ibase_->get_script_info(this->input_file_index_);
 715   Timespec mtime = this->input_reader_->get_mtime();
 716   incremental_inputs->report_script(script_info, arg_serial, mtime);
 717 }
 718
 719 // Class Check_library.
 720
 721 Check_library::~Check_library()
 722 {
 723   if (this->this_blocker_ != NULL)
 724     delete this->this_blocker_;
 725   // next_blocker_ is deleted by the task associated with the next
 726   // input file.
 727 }
 728
 729 // Return whether a Check_library task is runnable.
 730
 731 Task_token*
 732 Check_library::is_runnable()
 733 {
 734   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 735     return this->this_blocker_;
 736   return NULL;
 737 }
 738
 739 void
 740 Check_library::locks(Task_locker* tl)
 741 {
 742   tl->add(this, this->next_blocker_);
 743 }
 744
 745 // Run a Check_library task.
 746
 747 void
 748 Check_library::run(Workqueue*)
 749 {
 750   Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
 751   gold_assert(incremental_inputs != NULL);
 752   Incremental_library* lib = this->ibase_->get_library(this->input_file_index_);
 753   gold_assert(lib != NULL);
 754   lib->copy_unused_symbols();
 755   // FIXME: Check that unused symbols remain unused.
 756   if (!lib->is_reported())
 757     {
 758       unsigned int lib_serial = lib->arg_serial();
 759       unsigned int lib_index = lib->input_file_index();
 760       Script_info* script_info = this->ibase_->get_script_info(lib_index);
 761       incremental_inputs->report_archive_begin(lib, lib_serial, script_info);
 762     }
 763   incremental_inputs->report_archive_end(lib);
 764 }
 765
 766 // Class Input_group.
 767
 768 // When we delete an Input_group we can delete the archive
 769 // information.
 770
 771 Input_group::~Input_group()
 772 {
 773   for (Input_group::const_iterator p = this->begin();
 774        p != this->end();
 775        ++p)
 776     delete *p;
 777 }
 778
 779 // Class Start_group.
 780
 781 Start_group::~Start_group()
 782 {
 783   if (this->this_blocker_ != NULL)
 784     delete this->this_blocker_;
 785   // next_blocker_ is deleted by the task associated with the first
 786   // file in the group.
 787 }
 788
 789 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
 790
 791 Task_token*
 792 Start_group::is_runnable()
 793 {
 794   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 795     return this->this_blocker_;
 796   return NULL;
 797 }
 798
 799 void
 800 Start_group::locks(Task_locker* tl)
 801 {
 802   tl->add(this, this->next_blocker_);
 803 }
 804
 805 // Store the number of undefined symbols we see now.
 806
 807 void
 808 Start_group::run(Workqueue*)
 809 {
 810   this->finish_group_->set_saw_undefined(this->symtab_->saw_undefined());
 811 }
 812
 813 // Class Finish_group.
 814
 815 Finish_group::~Finish_group()
 816 {
 817   if (this->this_blocker_ != NULL)
 818     delete this->this_blocker_;
 819   // next_blocker_ is deleted by the task associated with the next
 820   // input file following the group.
 821 }
 822
 823 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
 824
 825 Task_token*
 826 Finish_group::is_runnable()
 827 {
 828   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 829     return this->this_blocker_;
 830   return NULL;
 831 }
 832
 833 void
 834 Finish_group::locks(Task_locker* tl)
 835 {
 836   tl->add(this, this->next_blocker_);
 837 }
 838
 839 // Loop over the archives until there are no new undefined symbols.
 840
 841 void
 842 Finish_group::run(Workqueue*)
 843 {
 844   size_t saw_undefined = this->saw_undefined_;
 845   while (saw_undefined != this->symtab_->saw_undefined())
 846     {
 847       saw_undefined = this->symtab_->saw_undefined();
 848
 849       for (Input_group::const_iterator p = this->input_group_->begin();
 850            p != this->input_group_->end();
 851            ++p)
 852         {
 853           Task_lock_obj<Archive> tl(this, *p);
 854
 855           (*p)->add_symbols(this->symtab_, this->layout_,
 856                             this->input_objects_, this->mapfile_);
 857         }
 858     }
 859
 860   // Now that we're done with the archives, record the incremental
 861   // layout information.
 862   for (Input_group::const_iterator p = this->input_group_->begin();
 863        p != this->input_group_->end();
 864        ++p)
 865     {
 866       // For an incremental link, finish recording the layout information.
 867       Incremental_inputs* incremental_inputs =
 868           this->layout_->incremental_inputs();
 869       if (incremental_inputs != NULL)
 870         incremental_inputs->report_archive_end(*p);
 871     }
 872
 873   if (parameters->options().has_plugins())
 874     parameters->options().plugins()->save_input_group(this->input_group_);
 875   else
 876     delete this->input_group_;
 877 }
 878
 879 // Class Read_script
 880
 881 Read_script::~Read_script()
 882 {
 883   if (this->this_blocker_ != NULL)
 884     delete this->this_blocker_;
 885   // next_blocker_ is deleted by the task associated with the next
 886   // input file.
 887 }
 888
 889 // We are blocked by this_blocker_.
 890
 891 Task_token*
 892 Read_script::is_runnable()
 893 {
 894   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 895     return this->this_blocker_;
 896   return NULL;
 897 }
 898
 899 // We don't unlock next_blocker_ here.  If the script names any input
 900 // files, then the last file will be responsible for unlocking it.
 901
 902 void
 903 Read_script::locks(Task_locker*)
 904 {
 905 }
 906
 907 // Read the script, if it is a script.
 908
 909 void
 910 Read_script::run(Workqueue* workqueue)
 911 {
 912   bool used_next_blocker;
 913   if (!read_input_script(workqueue, this->symtab_, this->layout_,
 914                          this->dirpath_, this->dirindex_, this->input_objects_,
 915                          this->mapfile_, this->input_group_,
 916                          this->input_argument_, this->input_file_,
 917                          this->next_blocker_, &used_next_blocker))
 918     {
 919       // Here we have to handle any other input file types we need.
 920       gold_error(_("%s: not an object or archive"),
 921                  this->input_file_->file().filename().c_str());
 922     }
 923
 924   if (!used_next_blocker)
 925     {
 926       // Queue up a task to unlock next_blocker.  We can't just unlock
 927       // it here, as we don't hold the workqueue lock.
 928       workqueue->queue_soon(new Unblock_token(NULL, this->next_blocker_));
 929     }
 930 }
 931
 932 // Return a debugging name for a Read_script task.
 933
 934 std::string
 935 Read_script::get_name() const
 936 {
 937   std::string ret("Read_script ");
 938   if (this->input_argument_->file().is_lib())
 939     ret += "-l";
 940   else if (this->input_argument_->file().is_searched_file())
 941     ret += "-l:";
 942   ret += this->input_argument_->file().name();
 943   return ret;
 944 }
 945
 946 } // End namespace gold.