Fix a typo.
[binutils-gdb.git] / gold / gold.cc
index c39f99958588cb2cfcd0e6a00ea5c1776a5d823a..8d86a1bbb474bea9c9d3bb0cdf6c1772b219bbea 100644 (file)
@@ -1,4 +1,24 @@
-// ld.c -- linker main function
+// gold.cc -- main linker functions
+
+// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
+// Written by Ian Lance Taylor <iant@google.com>.
+
+// This file is part of gold.
+
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
 
 #include "gold.h"
 
 #include <cstdio>
 #include <cstring>
 #include <unistd.h>
+#include <algorithm>
+#include "libiberty.h"
 
 #include "options.h"
+#include "debug.h"
 #include "workqueue.h"
 #include "dirsearch.h"
 #include "readsyms.h"
 #include "symtab.h"
+#include "common.h"
 #include "object.h"
 #include "layout.h"
 #include "reloc.h"
+#include "defstd.h"
+#include "plugin.h"
 
 namespace gold
 {
@@ -24,36 +50,44 @@ const char* program_name;
 void
 gold_exit(bool status)
 {
+  if (parameters != NULL
+      && parameters->options_valid()
+      && parameters->options().has_plugins())
+    parameters->options().plugins()->cleanup();
+  if (!status && parameters != NULL && parameters->options_valid())
+    unlink_if_ordinary(parameters->options().output_file_name());
   exit(status ? EXIT_SUCCESS : EXIT_FAILURE);
 }
 
-void
-gold_fatal(const char* msg, bool perrno)
-{
-  fprintf(stderr, "%s: ", program_name);
-  if (perrno)
-    perror(msg);
-  else
-    fprintf(stderr, "%s\n", msg);
-  gold_exit(false);
-}
-
 void
 gold_nomem()
 {
   // We are out of memory, so try hard to print a reasonable message.
   // Note that we don't try to translate this message, since the
   // translation process itself will require memory.
-  write(2, program_name, strlen(program_name));
-  const char* const s = ": out of memory\n";
-  write(2, s, strlen(s));
+
+  // LEN only exists to avoid a pointless warning when write is
+  // declared with warn_use_result, as when compiling with
+  // -D_USE_FORTIFY on GNU/Linux.  Casting to void does not appear to
+  // work, at least not with gcc 4.3.0.
+
+  ssize_t len = write(2, program_name, strlen(program_name));
+  if (len >= 0)
+    {
+      const char* const s = ": out of memory\n";
+      len = write(2, s, strlen(s));
+    }
   gold_exit(false);
 }
 
+// Handle an unreachable case.
+
 void
-gold_unreachable()
+do_gold_unreachable(const char* filename, int lineno, const char* function)
 {
-  abort();
+  fprintf(stderr, _("%s: internal error in %s, at %s:%d\n"),
+         program_name, function, filename, lineno);
+  gold_exit(false);
 }
 
 // This class arranges to run the functions done in the middle of the
@@ -65,62 +99,80 @@ class Middle_runner : public Task_function_runner
   Middle_runner(const General_options& options,
                const Input_objects* input_objects,
                Symbol_table* symtab,
-               Layout* layout)
+               Layout* layout, Mapfile* mapfile)
     : options_(options), input_objects_(input_objects), symtab_(symtab),
-      layout_(layout)
+      layout_(layout), mapfile_(mapfile)
   { }
 
   void
-  run(Workqueue*);
+  run(Workqueue*, const Task*);
 
  private:
   const General_options& options_;
   const Input_objects* input_objects_;
   Symbol_table* symtab_;
   Layout* layout_;
+  Mapfile* mapfile_;
 };
 
 void
-Middle_runner::run(Workqueue* workqueue)
+Middle_runner::run(Workqueue* workqueue, const Task* task)
 {
-  queue_middle_tasks(this->options_, this->input_objects_, this->symtab_,
-                    this->layout_, workqueue);
+  queue_middle_tasks(this->options_, task, this->input_objects_, this->symtab_,
+                    this->layout_, workqueue, this->mapfile_);
 }
 
 // Queue up the initial set of tasks for this link job.
 
 void
 queue_initial_tasks(const General_options& options,
-                   const Dirsearch& search_path,
-                   const Input_argument_list& inputs,
+                   Dirsearch& search_path,
+                   const Command_line& cmdline,
                    Workqueue* workqueue, Input_objects* input_objects,
-                   Symbol_table* symtab, Layout* layout)
+                   Symbol_table* symtab, Layout* layout, Mapfile* mapfile)
 {
-  if (inputs.empty())
-    gold_fatal(_("no input files"), false);
+  if (cmdline.begin() == cmdline.end())
+    gold_fatal(_("no input files"));
+
+  int thread_count = options.thread_count_initial();
+  if (thread_count == 0)
+    thread_count = cmdline.number_of_input_files();
+  workqueue->set_thread_count(thread_count);
 
   // Read the input files.  We have to add the symbols to the symbol
   // table in order.  We do this by creating a separate blocker for
   // each input file.  We associate the blocker with the following
   // input file, to give us a convenient place to delete it.
   Task_token* this_blocker = NULL;
-  for (Input_argument_list::const_iterator p = inputs.begin();
-       p != inputs.end();
+  for (Command_line::const_iterator p = cmdline.begin();
+       p != cmdline.end();
        ++p)
     {
-      Task_token* next_blocker = new Task_token();
+      Task_token* next_blocker = new Task_token(true);
       next_blocker->add_blocker();
       workqueue->queue(new Read_symbols(options, input_objects, symtab, layout,
-                                       search_path, *p, this_blocker,
-                                       next_blocker));
+                                       &search_path, mapfile, &*p, NULL,
+                                       this_blocker, next_blocker));
+      this_blocker = next_blocker;
+    }
+
+  if (options.has_plugins())
+    {
+      Task_token* next_blocker = new Task_token(true);
+      next_blocker->add_blocker();
+      workqueue->queue(new Plugin_hook(options, input_objects, symtab, layout,
+                                      &search_path, mapfile, this_blocker,
+                                      next_blocker));
       this_blocker = next_blocker;
     }
 
   workqueue->queue(new Task_function(new Middle_runner(options,
                                                       input_objects,
                                                       symtab,
-                                                      layout),
-                                    this_blocker));
+                                                      layout,
+                                                      mapfile),
+                                    this_blocker,
+                                    "Task_function Middle_runner"));
 }
 
 // Queue up the middle set of tasks.  These are the tasks which run
@@ -129,11 +181,84 @@ queue_initial_tasks(const General_options& options,
 
 void
 queue_middle_tasks(const General_options& options,
+                  const Task* task,
                   const Input_objects* input_objects,
                   Symbol_table* symtab,
                   Layout* layout,
-                  Workqueue* workqueue)
+                  Workqueue* workqueue,
+                  Mapfile* mapfile)
 {
+  // 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)
+    set_parameters_target(&parameters->default_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().shared());
+  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_error(_("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 (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();
+
+  // See if any of the input definitions violate the One Definition Rule.
+  // TODO: if this is too slow, do this as a task, rather than inline.
+  symtab->detect_odr_violations(task, options.output_file_name());
+
+  // 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);
+
+  // Add any symbols named with -u options to the symbol table.
+  symtab->add_undefined_symbols_from_command_line();
+
+  // Attach sections to segments.
+  layout->attach_sections_to_segments();
+
+  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);
+    }
+
+  // Make sure we have symbols for any required group signatures.
+  layout->define_group_signatures(symtab);
+
   // 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
@@ -145,10 +270,10 @@ queue_middle_tasks(const General_options& options,
   // 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.
-  Task_token* blocker = new Task_token();
-  Task_token* symtab_lock = new Task_token();
-  for (Input_objects::Object_list::const_iterator p = input_objects->begin();
-       p != input_objects->end();
+  Task_token* blocker = new Task_token(true);
+  Task_token* symtab_lock = new Task_token(false);
+  for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+       p != input_objects->relobj_end();
        ++p)
     {
       // We can read and process the relocations in any order.  But we
@@ -157,23 +282,31 @@ queue_middle_tasks(const General_options& options,
       // relocations.  That task will in turn queue a task to wait
       // until it can write to the symbol table.
       blocker->add_blocker();
-      workqueue->queue(new Read_relocs(options, symtab, *p, symtab_lock,
-                                      blocker));
+      workqueue->queue(new Read_relocs(options, symtab, layout, *p,
+                                      symtab_lock, blocker));
     }
 
   // Allocate common symbols.  This requires write access to the
   // symbol table, but is independent of the relocation processing.
-  // blocker->add_blocker();
-  // workqueue->queue(new Allocate_commons_task(options, symtab, layout,
-  //                                        symtab_lock, blocker));
+  if (parameters->options().define_common())
+    {
+      blocker->add_blocker();
+      workqueue->queue(new Allocate_commons_task(symtab, layout, mapfile,
+                                                symtab_lock, blocker));
+    }
 
   // When all those tasks are complete, we can start laying out the
   // output file.
+  // TODO(csilvers): figure out a more principled way to get the target
+  Target* target = const_cast<Target*>(&parameters->target());
   workqueue->queue(new Task_function(new Layout_task_runner(options,
                                                            input_objects,
                                                            symtab,
-                                                           layout),
-                                    blocker));
+                                                            target,
+                                                           layout,
+                                                           mapfile),
+                                    blocker,
+                                    "Task_function Layout_task_runner"));
 }
 
 // Queue up the final set of tasks.  This is called at the end of
@@ -183,85 +316,94 @@ void
 queue_final_tasks(const General_options& options,
                  const Input_objects* input_objects,
                  const Symbol_table* symtab,
-                 const Layout* layout,
+                 Layout* layout,
                  Workqueue* workqueue,
                  Output_file* of)
 {
+  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);
+
+  // 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);
+
   // Use a blocker to block the final cleanup task.
-  Task_token* final_blocker = new Task_token();
+  Task_token* final_blocker = new Task_token(true);
+
+  // Queue a task to write out the symbol table.
+  final_blocker->add_blocker();
+  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.
+  output_sections_blocker->add_blocker();
+  final_blocker->add_blocker();
+  workqueue->queue(new Write_sections_task(layout, of, output_sections_blocker,
+                                          final_blocker));
+
+  // Queue a task to write out everything else.
+  final_blocker->add_blocker();
+  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::Object_list::const_iterator p = input_objects->begin();
-       p != input_objects->end();
+  for (Input_objects::Relobj_iterator p = input_objects->relobj_begin();
+       p != input_objects->relobj_end();
        ++p)
     {
+      if (input_sections_blocker != NULL)
+       input_sections_blocker->add_blocker();
       final_blocker->add_blocker();
       workqueue->queue(new Relocate_task(options, symtab, layout, *p, of,
+                                        input_sections_blocker,
+                                        output_sections_blocker,
                                         final_blocker));
     }
 
-  // Queue a task to write out the symbol table.
-  final_blocker->add_blocker();
-  workqueue->queue(new Write_symbols_task(symtab, input_objects->target(),
-                                         layout->sympool(), of,
-                                         final_blocker));
-
-  // Queue a task to write out everything else.
-  final_blocker->add_blocker();
-  workqueue->queue(new Write_data_task(layout, of, 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)
+    {
+      final_blocker->add_blocker();
+      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;
+    }
 
   // Queue a task to close the output file.  This will be blocked by
   // FINAL_BLOCKER.
-  workqueue->queue(new Task_function(new Close_task_runner(of),
-                                    final_blocker));
+  workqueue->queue(new Task_function(new Close_task_runner(&options, layout,
+                                                          of),
+                                    final_blocker,
+                                    "Task_function Close_task_runner"));
 }
 
 } // End namespace gold.
-
-using namespace gold;
-
-int
-main(int argc, char** argv)
-{
-#if defined (HAVE_SETLOCALE) && defined (HAVE_LC_MESSAGES)
-  setlocale (LC_MESSAGES, "");
-#endif
-#if defined (HAVE_SETLOCALE)
-  setlocale (LC_CTYPE, "");
-#endif
-  bindtextdomain (PACKAGE, LOCALEDIR);
-  textdomain (PACKAGE);
-
-  gold::program_name = argv[0];
-
-  // Handle the command line options.
-  gold::Command_line command_line;
-  command_line.process(argc - 1, argv + 1);
-
-  // The work queue.
-  gold::Workqueue workqueue(command_line.options());
-
-  // The list of input objects.
-  Input_objects input_objects;
-
-  // The symbol table.
-  Symbol_table symtab;
-
-  // The layout object.
-  Layout layout(command_line.options());
-
-  // Get the search path from the -L options.
-  Dirsearch search_path;
-  search_path.add(&workqueue, command_line.options().search_path());
-
-  // Queue up the first set of tasks.
-  queue_initial_tasks(command_line.options(), search_path,
-                     command_line.inputs(), &workqueue, &input_objects,
-                     &symtab, &layout);
-
-  // Run the main task processing loop.
-  workqueue.process();
-
-  gold::gold_exit(true);
-}