gold/readsyms.cc

   1 // readsyms.cc -- read input file symbols for gold
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010 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.
 165   if (!this->do_read_symbols(workqueue))
 166     workqueue->queue_soon(new Unblock_token(this->this_blocker_,
 167                                             this->next_blocker_));
 168 }
 169
 170 // Handle a whole lib group. Other then collecting statisticts, this just
 171 // mimics what we do for regular object files in the command line.
 172
 173 bool
 174 Read_symbols::do_whole_lib_group(Workqueue* workqueue)
 175 {
 176   const Input_file_lib* lib_group = this->input_argument_->lib();
 177
 178   ++Lib_group::total_lib_groups;
 179
 180   Task_token* this_blocker = this->this_blocker_;
 181   for (Input_file_lib::const_iterator i = lib_group->begin();
 182        i != lib_group->end();
 183        ++i)
 184     {
 185       ++Lib_group::total_members;
 186       ++Lib_group::total_members_loaded;
 187
 188       const Input_argument* arg = &*i;
 189
 190       Task_token* next_blocker;
 191       if (i != lib_group->end() - 1)
 192         {
 193           next_blocker = new Task_token(true);
 194           next_blocker->add_blocker();
 195         }
 196       else
 197         next_blocker = this->next_blocker_;
 198
 199       workqueue->queue_soon(new Read_symbols(this->input_objects_,
 200                                              this->symtab_, this->layout_,
 201                                              this->dirpath_, this->dirindex_,
 202                                              this->mapfile_, arg, NULL,
 203                                              NULL, this_blocker, next_blocker));
 204       this_blocker = next_blocker;
 205     }
 206
 207   return true;
 208 }
 209
 210 // Handle a lib group. We set Read_symbols Tasks as usual, but have them
 211 // just record the symbol data instead of adding the objects.  We also start
 212 // a Add_lib_group_symbols Task which runs after we've read all the symbols.
 213 // In that task we process the members in a loop until we are done.
 214
 215 bool
 216 Read_symbols::do_lib_group(Workqueue* workqueue)
 217 {
 218   const Input_file_lib* lib_group = this->input_argument_->lib();
 219
 220   if (lib_group->options().whole_archive())
 221     return this->do_whole_lib_group(workqueue);
 222
 223   Lib_group* lib = new Lib_group(lib_group, this);
 224
 225   Add_lib_group_symbols* add_lib_group_symbols =
 226     new Add_lib_group_symbols(this->symtab_, this->layout_,
 227                               this->input_objects_,
 228                               lib, this->next_blocker_);
 229
 230
 231   Task_token* next_blocker = new Task_token(true);
 232   int j = 0;
 233   for (Input_file_lib::const_iterator i = lib_group->begin();
 234        i != lib_group->end();
 235        ++i, ++j)
 236     {
 237       const Input_argument* arg = &*i;
 238       Archive_member* m = lib->get_member(j);
 239
 240       next_blocker->add_blocker();
 241
 242       // Since this Read_symbols will not create an Add_symbols,
 243       // just pass NULL as this_blocker.
 244       workqueue->queue_soon(new Read_symbols(this->input_objects_,
 245                                              this->symtab_, this->layout_,
 246                                              this->dirpath_, this->dirindex_,
 247                                              this->mapfile_, arg, NULL,
 248                                              m, NULL, next_blocker));
 249     }
 250
 251   add_lib_group_symbols->set_blocker(next_blocker);
 252   workqueue->queue_soon(add_lib_group_symbols);
 253
 254   return true;
 255 }
 256
 257 // Open the file and read the symbols.  Return true if a new task was
 258 // queued, false if that could not happen due to some error.
 259
 260 bool
 261 Read_symbols::do_read_symbols(Workqueue* workqueue)
 262 {
 263   if (this->input_argument_->is_group())
 264     {
 265       gold_assert(this->input_group_ == NULL);
 266       this->do_group(workqueue);
 267       return true;
 268     }
 269
 270   if (this->input_argument_->is_lib())
 271     return this->do_lib_group(workqueue);
 272
 273   Input_file* input_file = new Input_file(&this->input_argument_->file());
 274   if (!input_file->open(*this->dirpath_, this, &this->dirindex_))
 275     return false;
 276
 277   // Read enough of the file to pick up the entire ELF header.
 278
 279   off_t filesize = input_file->file().filesize();
 280
 281   if (filesize == 0)
 282     {
 283       gold_error(_("%s: file is empty"),
 284                  input_file->file().filename().c_str());
 285       return false;
 286     }
 287
 288   const unsigned char* ehdr;
 289   int read_size;
 290   bool is_elf = is_elf_object(input_file, 0, &ehdr, &read_size);
 291
 292   if (read_size >= Archive::sarmag)
 293     {
 294       bool is_thin_archive
 295           = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0;
 296       if (is_thin_archive
 297           || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0)
 298         {
 299           // This is an archive.
 300           Archive* arch = new Archive(this->input_argument_->file().name(),
 301                                       input_file, is_thin_archive,
 302                                       this->dirpath_, this);
 303           arch->setup();
 304
 305           if (this->layout_->incremental_inputs())
 306             {
 307               const Input_argument* ia = this->input_argument_;
 308               this->layout_->incremental_inputs()->report_archive(ia, arch);
 309             }
 310
 311           // Unlock the archive so it can be used in the next task.
 312           arch->unlock(this);
 313
 314           workqueue->queue_next(new Add_archive_symbols(this->symtab_,
 315                                                         this->layout_,
 316                                                         this->input_objects_,
 317                                                         this->dirpath_,
 318                                                         this->dirindex_,
 319                                                         this->mapfile_,
 320                                                         this->input_argument_,
 321                                                         arch,
 322                                                         this->input_group_,
 323                                                         this->this_blocker_,
 324                                                         this->next_blocker_));
 325           return true;
 326         }
 327     }
 328
 329   if (parameters->options().has_plugins())
 330     {
 331       Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
 332                                                                    0, filesize);
 333       if (obj != NULL)
 334         {
 335           // The input file was claimed by a plugin, and its symbols
 336           // have been provided by the plugin.
 337
 338           // We are done with the file at this point, so unlock it.
 339           obj->unlock(this);
 340
 341           if (this->member_ != NULL)
 342             {
 343               this->member_->sd_ = NULL;
 344               this->member_->obj_ = obj;
 345               return true;
 346             }
 347
 348           workqueue->queue_next(new Add_symbols(this->input_objects_,
 349                                                 this->symtab_,
 350                                                 this->layout_,
 351                                                 this->dirpath_,
 352                                                 this->dirindex_,
 353                                                 this->mapfile_,
 354                                                 this->input_argument_,
 355                                                 obj,
 356                                                 NULL,
 357                                                 this->this_blocker_,
 358                                                 this->next_blocker_));
 359           return true;
 360         }
 361     }
 362
 363   if (is_elf)
 364     {
 365       // This is an ELF object.
 366
 367       bool unconfigured = false;
 368       bool* punconfigured = (input_file->will_search_for()
 369                              ? &unconfigured
 370                              : NULL);
 371       Object* obj = make_elf_object(input_file->filename(),
 372                                     input_file, 0, ehdr, read_size,
 373                                     punconfigured);
 374       if (obj == NULL)
 375         {
 376           if (unconfigured)
 377             {
 378               Read_symbols::incompatible_warning(this->input_argument_,
 379                                                  input_file);
 380               input_file->file().release();
 381               input_file->file().unlock(this);
 382               delete input_file;
 383               ++this->dirindex_;
 384               return this->do_read_symbols(workqueue);
 385             }
 386           return false;
 387         }
 388
 389       Read_symbols_data* sd = new Read_symbols_data;
 390       obj->read_symbols(sd);
 391
 392       if (this->layout_->incremental_inputs())
 393         {
 394           const Input_argument* ia = this->input_argument_;
 395           this->layout_->incremental_inputs()->report_object(ia, obj);
 396         }
 397
 398       // Opening the file locked it, so now we need to unlock it.  We
 399       // need to unlock it before queuing the Add_symbols task,
 400       // because the workqueue doesn't know about our lock on the
 401       // file.  If we queue the Add_symbols task first, it will be
 402       // stuck on the end of the file lock, but since the workqueue
 403       // doesn't know about that lock, it will never release the
 404       // Add_symbols task.
 405
 406       input_file->file().unlock(this);
 407
 408       if (this->member_ != NULL)
 409         {
 410           this->member_->sd_ = sd;
 411           this->member_->obj_ = obj;
 412           return true;
 413         }
 414
 415       // We use queue_next because everything is cached for this
 416       // task to run right away if possible.
 417
 418       workqueue->queue_next(new Add_symbols(this->input_objects_,
 419                                             this->symtab_, this->layout_,
 420                                             this->dirpath_,
 421                                             this->dirindex_,
 422                                             this->mapfile_,
 423                                             this->input_argument_,
 424                                             obj,
 425                                             sd,
 426                                             this->this_blocker_,
 427                                             this->next_blocker_));
 428
 429       return true;
 430     }
 431
 432   // Queue up a task to try to parse this file as a script.  We use a
 433   // separate task so that the script will be read in order with other
 434   // objects named on the command line.  Also so that we don't try to
 435   // read multiple scripts simultaneously, which could lead to
 436   // unpredictable changes to the General_options structure.
 437
 438   workqueue->queue_soon(new Read_script(this->symtab_,
 439                                         this->layout_,
 440                                         this->dirpath_,
 441                                         this->dirindex_,
 442                                         this->input_objects_,
 443                                         this->mapfile_,
 444                                         this->input_group_,
 445                                         this->input_argument_,
 446                                         input_file,
 447                                         this->this_blocker_,
 448                                         this->next_blocker_));
 449   return true;
 450 }
 451
 452 // Handle a group.  We need to walk through the arguments over and
 453 // over until we don't see any new undefined symbols.  We do this by
 454 // setting off Read_symbols Tasks as usual, but recording the archive
 455 // entries instead of deleting them.  We also start a Finish_group
 456 // Task which runs after we've read all the symbols.  In that task we
 457 // process the archives in a loop until we are done.
 458
 459 void
 460 Read_symbols::do_group(Workqueue* workqueue)
 461 {
 462   Input_group* input_group = new Input_group();
 463
 464   const Input_file_group* group = this->input_argument_->group();
 465   Task_token* this_blocker = this->this_blocker_;
 466
 467   Finish_group* finish_group = new Finish_group(this->input_objects_,
 468                                                 this->symtab_,
 469                                                 this->layout_,
 470                                                 this->mapfile_,
 471                                                 input_group,
 472                                                 this->next_blocker_);
 473
 474   Task_token* next_blocker = new Task_token(true);
 475   next_blocker->add_blocker();
 476   workqueue->queue_soon(new Start_group(this->symtab_, finish_group,
 477                                         this_blocker, next_blocker));
 478   this_blocker = next_blocker;
 479
 480   for (Input_file_group::const_iterator p = group->begin();
 481        p != group->end();
 482        ++p)
 483     {
 484       const Input_argument* arg = &*p;
 485       gold_assert(arg->is_file());
 486
 487       next_blocker = new Task_token(true);
 488       next_blocker->add_blocker();
 489       workqueue->queue_soon(new Read_symbols(this->input_objects_,
 490                                              this->symtab_, this->layout_,
 491                                              this->dirpath_, this->dirindex_,
 492                                              this->mapfile_, arg, input_group,
 493                                              NULL, this_blocker, next_blocker));
 494       this_blocker = next_blocker;
 495     }
 496
 497   finish_group->set_blocker(this_blocker);
 498
 499   workqueue->queue_soon(finish_group);
 500 }
 501
 502 // Return a debugging name for a Read_symbols task.
 503
 504 std::string
 505 Read_symbols::get_name() const
 506 {
 507   if (this->input_argument_->is_group())
 508     {
 509       std::string ret("Read_symbols group (");
 510       bool add_space = false;
 511       const Input_file_group* group = this->input_argument_->group();
 512       for (Input_file_group::const_iterator p = group->begin();
 513            p != group->end();
 514            ++p)
 515       {
 516         if (add_space)
 517           ret += ' ';
 518         ret += p->file().name();
 519         add_space = true;
 520       }
 521       return ret + ')';
 522     }
 523   else if (this->input_argument_->is_lib())
 524     {
 525       std::string ret("Read_symbols lib (");
 526       bool add_space = false;
 527       const Input_file_lib* lib = this->input_argument_->lib();
 528       for (Input_file_lib::const_iterator p = lib->begin();
 529            p != lib->end();
 530            ++p)
 531       {
 532         if (add_space)
 533           ret += ' ';
 534         ret += p->file().name();
 535         add_space = true;
 536       }
 537       return ret + ')';
 538     }
 539   else
 540     {
 541       std::string ret("Read_symbols ");
 542       if (this->input_argument_->file().is_lib())
 543         ret += "-l";
 544       else if (this->input_argument_->file().is_searched_file())
 545         ret += "-l:";
 546       ret += this->input_argument_->file().name();
 547       return ret;
 548     }
 549 }
 550
 551 // Class Add_symbols.
 552
 553 Add_symbols::~Add_symbols()
 554 {
 555   if (this->this_blocker_ != NULL)
 556     delete this->this_blocker_;
 557   // next_blocker_ is deleted by the task associated with the next
 558   // input file.
 559 }
 560
 561 // We are blocked by this_blocker_.  We block next_blocker_.  We also
 562 // lock the file.
 563
 564 Task_token*
 565 Add_symbols::is_runnable()
 566 {
 567   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 568     return this->this_blocker_;
 569   if (this->object_->is_locked())
 570     return this->object_->token();
 571   return NULL;
 572 }
 573
 574 void
 575 Add_symbols::locks(Task_locker* tl)
 576 {
 577   tl->add(this, this->next_blocker_);
 578   tl->add(this, this->object_->token());
 579 }
 580
 581 // Add the symbols in the object to the symbol table.
 582
 583 void
 584 Add_symbols::run(Workqueue*)
 585 {
 586   Pluginobj* pluginobj = this->object_->pluginobj();
 587   if (pluginobj != NULL)
 588     {
 589       this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
 590       return;
 591     }
 592
 593   if (!this->input_objects_->add_object(this->object_))
 594     {
 595       delete this->sd_;
 596       this->sd_ = NULL;
 597       this->object_->release();
 598       delete this->object_;
 599     }
 600   else
 601     {
 602       this->object_->layout(this->symtab_, this->layout_, this->sd_);
 603       this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
 604       delete this->sd_;
 605       this->sd_ = NULL;
 606       this->object_->release();
 607     }
 608 }
 609
 610 // Class Start_group.
 611
 612 Start_group::~Start_group()
 613 {
 614   if (this->this_blocker_ != NULL)
 615     delete this->this_blocker_;
 616   // next_blocker_ is deleted by the task associated with the first
 617   // file in the group.
 618 }
 619
 620 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
 621
 622 Task_token*
 623 Start_group::is_runnable()
 624 {
 625   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 626     return this->this_blocker_;
 627   return NULL;
 628 }
 629
 630 void
 631 Start_group::locks(Task_locker* tl)
 632 {
 633   tl->add(this, this->next_blocker_);
 634 }
 635
 636 // Store the number of undefined symbols we see now.
 637
 638 void
 639 Start_group::run(Workqueue*)
 640 {
 641   this->finish_group_->set_saw_undefined(this->symtab_->saw_undefined());
 642 }
 643
 644 // Class Finish_group.
 645
 646 Finish_group::~Finish_group()
 647 {
 648   if (this->this_blocker_ != NULL)
 649     delete this->this_blocker_;
 650   // next_blocker_ is deleted by the task associated with the next
 651   // input file following the group.
 652 }
 653
 654 // We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
 655
 656 Task_token*
 657 Finish_group::is_runnable()
 658 {
 659   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 660     return this->this_blocker_;
 661   return NULL;
 662 }
 663
 664 void
 665 Finish_group::locks(Task_locker* tl)
 666 {
 667   tl->add(this, this->next_blocker_);
 668 }
 669
 670 // Loop over the archives until there are no new undefined symbols.
 671
 672 void
 673 Finish_group::run(Workqueue*)
 674 {
 675   size_t saw_undefined = this->saw_undefined_;
 676   while (saw_undefined != this->symtab_->saw_undefined())
 677     {
 678       saw_undefined = this->symtab_->saw_undefined();
 679
 680       for (Input_group::const_iterator p = this->input_group_->begin();
 681            p != this->input_group_->end();
 682            ++p)
 683         {
 684           Task_lock_obj<Archive> tl(this, *p);
 685
 686           (*p)->add_symbols(this->symtab_, this->layout_,
 687                             this->input_objects_, this->mapfile_);
 688         }
 689     }
 690
 691   // Delete all the archives now that we no longer need them.
 692   for (Input_group::const_iterator p = this->input_group_->begin();
 693        p != this->input_group_->end();
 694        ++p)
 695     delete *p;
 696   delete this->input_group_;
 697 }
 698
 699 // Class Read_script
 700
 701 Read_script::~Read_script()
 702 {
 703   if (this->this_blocker_ != NULL)
 704     delete this->this_blocker_;
 705   // next_blocker_ is deleted by the task associated with the next
 706   // input file.
 707 }
 708
 709 // We are blocked by this_blocker_.
 710
 711 Task_token*
 712 Read_script::is_runnable()
 713 {
 714   if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
 715     return this->this_blocker_;
 716   return NULL;
 717 }
 718
 719 // We don't unlock next_blocker_ here.  If the script names any input
 720 // files, then the last file will be responsible for unlocking it.
 721
 722 void
 723 Read_script::locks(Task_locker*)
 724 {
 725 }
 726
 727 // Read the script, if it is a script.
 728
 729 void
 730 Read_script::run(Workqueue* workqueue)
 731 {
 732   bool used_next_blocker;
 733   if (!read_input_script(workqueue, this->symtab_, this->layout_,
 734                          this->dirpath_, this->dirindex_, this->input_objects_,
 735                          this->mapfile_, this->input_group_,
 736                          this->input_argument_, this->input_file_,
 737                          this->next_blocker_, &used_next_blocker))
 738     {
 739       // Here we have to handle any other input file types we need.
 740       gold_error(_("%s: not an object or archive"),
 741                  this->input_file_->file().filename().c_str());
 742     }
 743
 744   if (!used_next_blocker)
 745     {
 746       // Queue up a task to unlock next_blocker.  We can't just unlock
 747       // it here, as we don't hold the workqueue lock.
 748       workqueue->queue_soon(new Unblock_token(NULL, this->next_blocker_));
 749     }
 750 }
 751
 752 // Return a debugging name for a Read_script task.
 753
 754 std::string
 755 Read_script::get_name() const
 756 {
 757   std::string ret("Read_script ");
 758   if (this->input_argument_->file().is_lib())
 759     ret += "-l";
 760   else if (this->input_argument_->file().is_searched_file())
 761     ret += "-l:";
 762   ret += this->input_argument_->file().name();
 763   return ret;
 764 }
 765
 766 } // End namespace gold.