1 // layout.cc -- lay out output file sections for gold
3 // Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
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.
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.
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.
32 #include "libiberty.h"
36 #include "parameters.h"
40 #include "script-sections.h"
45 #include "compressed_output.h"
46 #include "reduced_debug_output.h"
48 #include "descriptors.h"
50 #include "incremental.h"
56 // Layout::Relaxation_debug_check methods.
58 // Check that sections and special data are in reset states.
59 // We do not save states for Output_sections and special Output_data.
60 // So we check that they have not assigned any addresses or offsets.
61 // clean_up_after_relaxation simply resets their addresses and offsets.
63 Layout::Relaxation_debug_check::check_output_data_for_reset_values(
64 const Layout::Section_list
& sections
,
65 const Layout::Data_list
& special_outputs
)
67 for(Layout::Section_list::const_iterator p
= sections
.begin();
70 gold_assert((*p
)->address_and_file_offset_have_reset_values());
72 for(Layout::Data_list::const_iterator p
= special_outputs
.begin();
73 p
!= special_outputs
.end();
75 gold_assert((*p
)->address_and_file_offset_have_reset_values());
78 // Save information of SECTIONS for checking later.
81 Layout::Relaxation_debug_check::read_sections(
82 const Layout::Section_list
& sections
)
84 for(Layout::Section_list::const_iterator p
= sections
.begin();
88 Output_section
* os
= *p
;
90 info
.output_section
= os
;
91 info
.address
= os
->is_address_valid() ? os
->address() : 0;
92 info
.data_size
= os
->is_data_size_valid() ? os
->data_size() : -1;
93 info
.offset
= os
->is_offset_valid()? os
->offset() : -1 ;
94 this->section_infos_
.push_back(info
);
98 // Verify SECTIONS using previously recorded information.
101 Layout::Relaxation_debug_check::verify_sections(
102 const Layout::Section_list
& sections
)
105 for(Layout::Section_list::const_iterator p
= sections
.begin();
109 Output_section
* os
= *p
;
110 uint64_t address
= os
->is_address_valid() ? os
->address() : 0;
111 off_t data_size
= os
->is_data_size_valid() ? os
->data_size() : -1;
112 off_t offset
= os
->is_offset_valid()? os
->offset() : -1 ;
114 if (i
>= this->section_infos_
.size())
116 gold_fatal("Section_info of %s missing.\n", os
->name());
118 const Section_info
& info
= this->section_infos_
[i
];
119 if (os
!= info
.output_section
)
120 gold_fatal("Section order changed. Expecting %s but see %s\n",
121 info
.output_section
->name(), os
->name());
122 if (address
!= info
.address
123 || data_size
!= info
.data_size
124 || offset
!= info
.offset
)
125 gold_fatal("Section %s changed.\n", os
->name());
129 // Layout_task_runner methods.
131 // Lay out the sections. This is called after all the input objects
135 Layout_task_runner::run(Workqueue
* workqueue
, const Task
* task
)
137 off_t file_size
= this->layout_
->finalize(this->input_objects_
,
142 // Now we know the final size of the output file and we know where
143 // each piece of information goes.
145 if (this->mapfile_
!= NULL
)
147 this->mapfile_
->print_discarded_sections(this->input_objects_
);
148 this->layout_
->print_to_mapfile(this->mapfile_
);
151 Output_file
* of
= new Output_file(parameters
->options().output_file_name());
152 if (this->options_
.oformat_enum() != General_options::OBJECT_FORMAT_ELF
)
153 of
->set_is_temporary();
156 // Queue up the final set of tasks.
157 gold::queue_final_tasks(this->options_
, this->input_objects_
,
158 this->symtab_
, this->layout_
, workqueue
, of
);
163 Layout::Layout(int number_of_input_files
, Script_options
* script_options
)
164 : number_of_input_files_(number_of_input_files
),
165 script_options_(script_options
),
173 unattached_section_list_(),
174 special_output_list_(),
175 section_headers_(NULL
),
177 relro_segment_(NULL
),
178 symtab_section_(NULL
),
179 symtab_xindex_(NULL
),
180 dynsym_section_(NULL
),
181 dynsym_xindex_(NULL
),
182 dynamic_section_(NULL
),
184 eh_frame_section_(NULL
),
185 eh_frame_data_(NULL
),
186 added_eh_frame_data_(false),
187 eh_frame_hdr_section_(NULL
),
188 build_id_note_(NULL
),
192 output_file_size_(-1),
193 sections_are_attached_(false),
194 input_requires_executable_stack_(false),
195 input_with_gnu_stack_note_(false),
196 input_without_gnu_stack_note_(false),
197 has_static_tls_(false),
198 any_postprocessing_sections_(false),
199 resized_signatures_(false),
200 have_stabstr_section_(false),
201 incremental_inputs_(NULL
),
202 record_output_section_data_from_script_(false),
203 script_output_section_data_list_(),
204 segment_states_(NULL
),
205 relaxation_debug_check_(NULL
)
207 // Make space for more than enough segments for a typical file.
208 // This is just for efficiency--it's OK if we wind up needing more.
209 this->segment_list_
.reserve(12);
211 // We expect two unattached Output_data objects: the file header and
212 // the segment headers.
213 this->special_output_list_
.reserve(2);
215 // Initialize structure needed for an incremental build.
216 if (parameters
->options().incremental())
217 this->incremental_inputs_
= new Incremental_inputs
;
219 // The section name pool is worth optimizing in all cases, because
220 // it is small, but there are often overlaps due to .rel sections.
221 this->namepool_
.set_optimize();
224 // Hash a key we use to look up an output section mapping.
227 Layout::Hash_key::operator()(const Layout::Key
& k
) const
229 return k
.first
+ k
.second
.first
+ k
.second
.second
;
232 // Returns whether the given section is in the list of
233 // debug-sections-used-by-some-version-of-gdb. Currently,
234 // we've checked versions of gdb up to and including 6.7.1.
236 static const char* gdb_sections
[] =
238 // ".debug_aranges", // not used by gdb as of 6.7.1
244 // ".debug_pubnames", // not used by gdb as of 6.7.1
249 static const char* lines_only_debug_sections
[] =
251 // ".debug_aranges", // not used by gdb as of 6.7.1
257 // ".debug_pubnames", // not used by gdb as of 6.7.1
263 is_gdb_debug_section(const char* str
)
265 // We can do this faster: binary search or a hashtable. But why bother?
266 for (size_t i
= 0; i
< sizeof(gdb_sections
)/sizeof(*gdb_sections
); ++i
)
267 if (strcmp(str
, gdb_sections
[i
]) == 0)
273 is_lines_only_debug_section(const char* str
)
275 // We can do this faster: binary search or a hashtable. But why bother?
277 i
< sizeof(lines_only_debug_sections
)/sizeof(*lines_only_debug_sections
);
279 if (strcmp(str
, lines_only_debug_sections
[i
]) == 0)
284 // Whether to include this section in the link.
286 template<int size
, bool big_endian
>
288 Layout::include_section(Sized_relobj
<size
, big_endian
>*, const char* name
,
289 const elfcpp::Shdr
<size
, big_endian
>& shdr
)
291 if (shdr
.get_sh_flags() & elfcpp::SHF_EXCLUDE
)
294 switch (shdr
.get_sh_type())
296 case elfcpp::SHT_NULL
:
297 case elfcpp::SHT_SYMTAB
:
298 case elfcpp::SHT_DYNSYM
:
299 case elfcpp::SHT_HASH
:
300 case elfcpp::SHT_DYNAMIC
:
301 case elfcpp::SHT_SYMTAB_SHNDX
:
304 case elfcpp::SHT_STRTAB
:
305 // Discard the sections which have special meanings in the ELF
306 // ABI. Keep others (e.g., .stabstr). We could also do this by
307 // checking the sh_link fields of the appropriate sections.
308 return (strcmp(name
, ".dynstr") != 0
309 && strcmp(name
, ".strtab") != 0
310 && strcmp(name
, ".shstrtab") != 0);
312 case elfcpp::SHT_RELA
:
313 case elfcpp::SHT_REL
:
314 case elfcpp::SHT_GROUP
:
315 // If we are emitting relocations these should be handled
317 gold_assert(!parameters
->options().relocatable()
318 && !parameters
->options().emit_relocs());
321 case elfcpp::SHT_PROGBITS
:
322 if (parameters
->options().strip_debug()
323 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
325 if (is_debug_info_section(name
))
328 if (parameters
->options().strip_debug_non_line()
329 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
331 // Debugging sections can only be recognized by name.
332 if (is_prefix_of(".debug", name
)
333 && !is_lines_only_debug_section(name
))
336 if (parameters
->options().strip_debug_gdb()
337 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
339 // Debugging sections can only be recognized by name.
340 if (is_prefix_of(".debug", name
)
341 && !is_gdb_debug_section(name
))
344 if (parameters
->options().strip_lto_sections()
345 && !parameters
->options().relocatable()
346 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
348 // Ignore LTO sections containing intermediate code.
349 if (is_prefix_of(".gnu.lto_", name
))
359 // Return an output section named NAME, or NULL if there is none.
362 Layout::find_output_section(const char* name
) const
364 for (Section_list::const_iterator p
= this->section_list_
.begin();
365 p
!= this->section_list_
.end();
367 if (strcmp((*p
)->name(), name
) == 0)
372 // Return an output segment of type TYPE, with segment flags SET set
373 // and segment flags CLEAR clear. Return NULL if there is none.
376 Layout::find_output_segment(elfcpp::PT type
, elfcpp::Elf_Word set
,
377 elfcpp::Elf_Word clear
) const
379 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
380 p
!= this->segment_list_
.end();
382 if (static_cast<elfcpp::PT
>((*p
)->type()) == type
383 && ((*p
)->flags() & set
) == set
384 && ((*p
)->flags() & clear
) == 0)
389 // Return the output section to use for section NAME with type TYPE
390 // and section flags FLAGS. NAME must be canonicalized in the string
391 // pool, and NAME_KEY is the key.
394 Layout::get_output_section(const char* name
, Stringpool::Key name_key
,
395 elfcpp::Elf_Word type
, elfcpp::Elf_Xword flags
)
397 elfcpp::Elf_Xword lookup_flags
= flags
;
399 // Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine
400 // read-write with read-only sections. Some other ELF linkers do
401 // not do this. FIXME: Perhaps there should be an option
403 lookup_flags
&= ~(elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
);
405 const Key
key(name_key
, std::make_pair(type
, lookup_flags
));
406 const std::pair
<Key
, Output_section
*> v(key
, NULL
);
407 std::pair
<Section_name_map::iterator
, bool> ins(
408 this->section_name_map_
.insert(v
));
411 return ins
.first
->second
;
414 // This is the first time we've seen this name/type/flags
415 // combination. For compatibility with the GNU linker, we
416 // combine sections with contents and zero flags with sections
417 // with non-zero flags. This is a workaround for cases where
418 // assembler code forgets to set section flags. FIXME: Perhaps
419 // there should be an option to control this.
420 Output_section
* os
= NULL
;
422 if (type
== elfcpp::SHT_PROGBITS
)
426 Output_section
* same_name
= this->find_output_section(name
);
427 if (same_name
!= NULL
428 && same_name
->type() == elfcpp::SHT_PROGBITS
429 && (same_name
->flags() & elfcpp::SHF_TLS
) == 0)
432 else if ((flags
& elfcpp::SHF_TLS
) == 0)
434 elfcpp::Elf_Xword zero_flags
= 0;
435 const Key
zero_key(name_key
, std::make_pair(type
, zero_flags
));
436 Section_name_map::iterator p
=
437 this->section_name_map_
.find(zero_key
);
438 if (p
!= this->section_name_map_
.end())
444 os
= this->make_output_section(name
, type
, flags
);
445 ins
.first
->second
= os
;
450 // Pick the output section to use for section NAME, in input file
451 // RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a
452 // linker created section. IS_INPUT_SECTION is true if we are
453 // choosing an output section for an input section found in a input
454 // file. This will return NULL if the input section should be
458 Layout::choose_output_section(const Relobj
* relobj
, const char* name
,
459 elfcpp::Elf_Word type
, elfcpp::Elf_Xword flags
,
460 bool is_input_section
)
462 // We should not see any input sections after we have attached
463 // sections to segments.
464 gold_assert(!is_input_section
|| !this->sections_are_attached_
);
466 // Some flags in the input section should not be automatically
467 // copied to the output section.
468 flags
&= ~ (elfcpp::SHF_INFO_LINK
469 | elfcpp::SHF_LINK_ORDER
472 | elfcpp::SHF_STRINGS
);
474 if (this->script_options_
->saw_sections_clause())
476 // We are using a SECTIONS clause, so the output section is
477 // chosen based only on the name.
479 Script_sections
* ss
= this->script_options_
->script_sections();
480 const char* file_name
= relobj
== NULL
? NULL
: relobj
->name().c_str();
481 Output_section
** output_section_slot
;
482 name
= ss
->output_section_name(file_name
, name
, &output_section_slot
);
485 // The SECTIONS clause says to discard this input section.
489 // If this is an orphan section--one not mentioned in the linker
490 // script--then OUTPUT_SECTION_SLOT will be NULL, and we do the
491 // default processing below.
493 if (output_section_slot
!= NULL
)
495 if (*output_section_slot
!= NULL
)
497 (*output_section_slot
)->update_flags_for_input_section(flags
);
498 return *output_section_slot
;
501 // We don't put sections found in the linker script into
502 // SECTION_NAME_MAP_. That keeps us from getting confused
503 // if an orphan section is mapped to a section with the same
504 // name as one in the linker script.
506 name
= this->namepool_
.add(name
, false, NULL
);
508 Output_section
* os
= this->make_output_section(name
, type
, flags
);
509 os
->set_found_in_sections_clause();
510 *output_section_slot
= os
;
515 // FIXME: Handle SHF_OS_NONCONFORMING somewhere.
517 // Turn NAME from the name of the input section into the name of the
520 size_t len
= strlen(name
);
522 && !this->script_options_
->saw_sections_clause()
523 && !parameters
->options().relocatable())
524 name
= Layout::output_section_name(name
, &len
);
526 Stringpool::Key name_key
;
527 name
= this->namepool_
.add_with_length(name
, len
, true, &name_key
);
529 // Find or make the output section. The output section is selected
530 // based on the section name, type, and flags.
531 return this->get_output_section(name
, name_key
, type
, flags
);
534 // Return the output section to use for input section SHNDX, with name
535 // NAME, with header HEADER, from object OBJECT. RELOC_SHNDX is the
536 // index of a relocation section which applies to this section, or 0
537 // if none, or -1U if more than one. RELOC_TYPE is the type of the
538 // relocation section if there is one. Set *OFF to the offset of this
539 // input section without the output section. Return NULL if the
540 // section should be discarded. Set *OFF to -1 if the section
541 // contents should not be written directly to the output file, but
542 // will instead receive special handling.
544 template<int size
, bool big_endian
>
546 Layout::layout(Sized_relobj
<size
, big_endian
>* object
, unsigned int shndx
,
547 const char* name
, const elfcpp::Shdr
<size
, big_endian
>& shdr
,
548 unsigned int reloc_shndx
, unsigned int, off_t
* off
)
552 if (!this->include_section(object
, name
, shdr
))
557 // In a relocatable link a grouped section must not be combined with
558 // any other sections.
559 if (parameters
->options().relocatable()
560 && (shdr
.get_sh_flags() & elfcpp::SHF_GROUP
) != 0)
562 name
= this->namepool_
.add(name
, true, NULL
);
563 os
= this->make_output_section(name
, shdr
.get_sh_type(),
564 shdr
.get_sh_flags());
568 os
= this->choose_output_section(object
, name
, shdr
.get_sh_type(),
569 shdr
.get_sh_flags(), true);
574 // By default the GNU linker sorts input sections whose names match
575 // .ctor.*, .dtor.*, .init_array.*, or .fini_array.*. The sections
576 // are sorted by name. This is used to implement constructor
577 // priority ordering. We are compatible.
578 if (!this->script_options_
->saw_sections_clause()
579 && (is_prefix_of(".ctors.", name
)
580 || is_prefix_of(".dtors.", name
)
581 || is_prefix_of(".init_array.", name
)
582 || is_prefix_of(".fini_array.", name
)))
583 os
->set_must_sort_attached_input_sections();
585 // FIXME: Handle SHF_LINK_ORDER somewhere.
587 *off
= os
->add_input_section(object
, shndx
, name
, shdr
, reloc_shndx
,
588 this->script_options_
->saw_sections_clause());
593 // Handle a relocation section when doing a relocatable link.
595 template<int size
, bool big_endian
>
597 Layout::layout_reloc(Sized_relobj
<size
, big_endian
>* object
,
599 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
600 Output_section
* data_section
,
601 Relocatable_relocs
* rr
)
603 gold_assert(parameters
->options().relocatable()
604 || parameters
->options().emit_relocs());
606 int sh_type
= shdr
.get_sh_type();
609 if (sh_type
== elfcpp::SHT_REL
)
611 else if (sh_type
== elfcpp::SHT_RELA
)
615 name
+= data_section
->name();
617 Output_section
* os
= this->choose_output_section(object
, name
.c_str(),
622 os
->set_should_link_to_symtab();
623 os
->set_info_section(data_section
);
625 Output_section_data
* posd
;
626 if (sh_type
== elfcpp::SHT_REL
)
628 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
629 posd
= new Output_relocatable_relocs
<elfcpp::SHT_REL
,
633 else if (sh_type
== elfcpp::SHT_RELA
)
635 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
636 posd
= new Output_relocatable_relocs
<elfcpp::SHT_RELA
,
643 os
->add_output_section_data(posd
);
644 rr
->set_output_data(posd
);
649 // Handle a group section when doing a relocatable link.
651 template<int size
, bool big_endian
>
653 Layout::layout_group(Symbol_table
* symtab
,
654 Sized_relobj
<size
, big_endian
>* object
,
656 const char* group_section_name
,
657 const char* signature
,
658 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
659 elfcpp::Elf_Word flags
,
660 std::vector
<unsigned int>* shndxes
)
662 gold_assert(parameters
->options().relocatable());
663 gold_assert(shdr
.get_sh_type() == elfcpp::SHT_GROUP
);
664 group_section_name
= this->namepool_
.add(group_section_name
, true, NULL
);
665 Output_section
* os
= this->make_output_section(group_section_name
,
667 shdr
.get_sh_flags());
669 // We need to find a symbol with the signature in the symbol table.
670 // If we don't find one now, we need to look again later.
671 Symbol
* sym
= symtab
->lookup(signature
, NULL
);
673 os
->set_info_symndx(sym
);
676 // Reserve some space to minimize reallocations.
677 if (this->group_signatures_
.empty())
678 this->group_signatures_
.reserve(this->number_of_input_files_
* 16);
680 // We will wind up using a symbol whose name is the signature.
681 // So just put the signature in the symbol name pool to save it.
682 signature
= symtab
->canonicalize_name(signature
);
683 this->group_signatures_
.push_back(Group_signature(os
, signature
));
686 os
->set_should_link_to_symtab();
689 section_size_type entry_count
=
690 convert_to_section_size_type(shdr
.get_sh_size() / 4);
691 Output_section_data
* posd
=
692 new Output_data_group
<size
, big_endian
>(object
, entry_count
, flags
,
694 os
->add_output_section_data(posd
);
697 // Special GNU handling of sections name .eh_frame. They will
698 // normally hold exception frame data as defined by the C++ ABI
699 // (http://codesourcery.com/cxx-abi/).
701 template<int size
, bool big_endian
>
703 Layout::layout_eh_frame(Sized_relobj
<size
, big_endian
>* object
,
704 const unsigned char* symbols
,
706 const unsigned char* symbol_names
,
707 off_t symbol_names_size
,
709 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
710 unsigned int reloc_shndx
, unsigned int reloc_type
,
713 gold_assert(shdr
.get_sh_type() == elfcpp::SHT_PROGBITS
);
714 gold_assert((shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) != 0);
716 const char* const name
= ".eh_frame";
717 Output_section
* os
= this->choose_output_section(object
,
719 elfcpp::SHT_PROGBITS
,
725 if (this->eh_frame_section_
== NULL
)
727 this->eh_frame_section_
= os
;
728 this->eh_frame_data_
= new Eh_frame();
730 if (parameters
->options().eh_frame_hdr())
732 Output_section
* hdr_os
=
733 this->choose_output_section(NULL
,
735 elfcpp::SHT_PROGBITS
,
741 Eh_frame_hdr
* hdr_posd
= new Eh_frame_hdr(os
,
742 this->eh_frame_data_
);
743 hdr_os
->add_output_section_data(hdr_posd
);
745 hdr_os
->set_after_input_sections();
747 if (!this->script_options_
->saw_phdrs_clause())
749 Output_segment
* hdr_oseg
;
750 hdr_oseg
= this->make_output_segment(elfcpp::PT_GNU_EH_FRAME
,
752 hdr_oseg
->add_output_section(hdr_os
, elfcpp::PF_R
);
755 this->eh_frame_data_
->set_eh_frame_hdr(hdr_posd
);
760 gold_assert(this->eh_frame_section_
== os
);
762 if (this->eh_frame_data_
->add_ehframe_input_section(object
,
771 os
->update_flags_for_input_section(shdr
.get_sh_flags());
773 // We found a .eh_frame section we are going to optimize, so now
774 // we can add the set of optimized sections to the output
775 // section. We need to postpone adding this until we've found a
776 // section we can optimize so that the .eh_frame section in
777 // crtbegin.o winds up at the start of the output section.
778 if (!this->added_eh_frame_data_
)
780 os
->add_output_section_data(this->eh_frame_data_
);
781 this->added_eh_frame_data_
= true;
787 // We couldn't handle this .eh_frame section for some reason.
788 // Add it as a normal section.
789 bool saw_sections_clause
= this->script_options_
->saw_sections_clause();
790 *off
= os
->add_input_section(object
, shndx
, name
, shdr
, reloc_shndx
,
791 saw_sections_clause
);
797 // Add POSD to an output section using NAME, TYPE, and FLAGS. Return
798 // the output section.
801 Layout::add_output_section_data(const char* name
, elfcpp::Elf_Word type
,
802 elfcpp::Elf_Xword flags
,
803 Output_section_data
* posd
)
805 Output_section
* os
= this->choose_output_section(NULL
, name
, type
, flags
,
808 os
->add_output_section_data(posd
);
812 // Map section flags to segment flags.
815 Layout::section_flags_to_segment(elfcpp::Elf_Xword flags
)
817 elfcpp::Elf_Word ret
= elfcpp::PF_R
;
818 if ((flags
& elfcpp::SHF_WRITE
) != 0)
820 if ((flags
& elfcpp::SHF_EXECINSTR
) != 0)
825 // Sometimes we compress sections. This is typically done for
826 // sections that are not part of normal program execution (such as
827 // .debug_* sections), and where the readers of these sections know
828 // how to deal with compressed sections. This routine doesn't say for
829 // certain whether we'll compress -- it depends on commandline options
830 // as well -- just whether this section is a candidate for compression.
831 // (The Output_compressed_section class decides whether to compress
832 // a given section, and picks the name of the compressed section.)
835 is_compressible_debug_section(const char* secname
)
837 return (strncmp(secname
, ".debug", sizeof(".debug") - 1) == 0);
840 // Make a new Output_section, and attach it to segments as
844 Layout::make_output_section(const char* name
, elfcpp::Elf_Word type
,
845 elfcpp::Elf_Xword flags
)
848 if ((flags
& elfcpp::SHF_ALLOC
) == 0
849 && strcmp(parameters
->options().compress_debug_sections(), "none") != 0
850 && is_compressible_debug_section(name
))
851 os
= new Output_compressed_section(¶meters
->options(), name
, type
,
854 else if ((flags
& elfcpp::SHF_ALLOC
) == 0
855 && parameters
->options().strip_debug_non_line()
856 && strcmp(".debug_abbrev", name
) == 0)
858 os
= this->debug_abbrev_
= new Output_reduced_debug_abbrev_section(
860 if (this->debug_info_
)
861 this->debug_info_
->set_abbreviations(this->debug_abbrev_
);
863 else if ((flags
& elfcpp::SHF_ALLOC
) == 0
864 && parameters
->options().strip_debug_non_line()
865 && strcmp(".debug_info", name
) == 0)
867 os
= this->debug_info_
= new Output_reduced_debug_info_section(
869 if (this->debug_abbrev_
)
870 this->debug_info_
->set_abbreviations(this->debug_abbrev_
);
873 os
= new Output_section(name
, type
, flags
);
875 parameters
->target().new_output_section(os
);
877 this->section_list_
.push_back(os
);
879 // The GNU linker by default sorts some sections by priority, so we
880 // do the same. We need to know that this might happen before we
881 // attach any input sections.
882 if (!this->script_options_
->saw_sections_clause()
883 && (strcmp(name
, ".ctors") == 0
884 || strcmp(name
, ".dtors") == 0
885 || strcmp(name
, ".init_array") == 0
886 || strcmp(name
, ".fini_array") == 0))
887 os
->set_may_sort_attached_input_sections();
889 // With -z relro, we have to recognize the special sections by name.
890 // There is no other way.
891 if (!this->script_options_
->saw_sections_clause()
892 && parameters
->options().relro()
893 && type
== elfcpp::SHT_PROGBITS
894 && (flags
& elfcpp::SHF_ALLOC
) != 0
895 && (flags
& elfcpp::SHF_WRITE
) != 0)
897 if (strcmp(name
, ".data.rel.ro") == 0)
899 else if (strcmp(name
, ".data.rel.ro.local") == 0)
902 os
->set_is_relro_local();
906 // Check for .stab*str sections, as .stab* sections need to link to
908 if (type
== elfcpp::SHT_STRTAB
909 && !this->have_stabstr_section_
910 && strncmp(name
, ".stab", 5) == 0
911 && strcmp(name
+ strlen(name
) - 3, "str") == 0)
912 this->have_stabstr_section_
= true;
914 // If we have already attached the sections to segments, then we
915 // need to attach this one now. This happens for sections created
916 // directly by the linker.
917 if (this->sections_are_attached_
)
918 this->attach_section_to_segment(os
);
923 // Attach output sections to segments. This is called after we have
924 // seen all the input sections.
927 Layout::attach_sections_to_segments()
929 for (Section_list::iterator p
= this->section_list_
.begin();
930 p
!= this->section_list_
.end();
932 this->attach_section_to_segment(*p
);
934 this->sections_are_attached_
= true;
937 // Attach an output section to a segment.
940 Layout::attach_section_to_segment(Output_section
* os
)
942 if ((os
->flags() & elfcpp::SHF_ALLOC
) == 0)
943 this->unattached_section_list_
.push_back(os
);
945 this->attach_allocated_section_to_segment(os
);
948 // Attach an allocated output section to a segment.
951 Layout::attach_allocated_section_to_segment(Output_section
* os
)
953 elfcpp::Elf_Xword flags
= os
->flags();
954 gold_assert((flags
& elfcpp::SHF_ALLOC
) != 0);
956 if (parameters
->options().relocatable())
959 // If we have a SECTIONS clause, we can't handle the attachment to
960 // segments until after we've seen all the sections.
961 if (this->script_options_
->saw_sections_clause())
964 gold_assert(!this->script_options_
->saw_phdrs_clause());
966 // This output section goes into a PT_LOAD segment.
968 elfcpp::Elf_Word seg_flags
= Layout::section_flags_to_segment(flags
);
970 // In general the only thing we really care about for PT_LOAD
971 // segments is whether or not they are writable, so that is how we
972 // search for them. Large data sections also go into their own
973 // PT_LOAD segment. People who need segments sorted on some other
974 // basis will have to use a linker script.
976 Segment_list::const_iterator p
;
977 for (p
= this->segment_list_
.begin();
978 p
!= this->segment_list_
.end();
981 if ((*p
)->type() != elfcpp::PT_LOAD
)
983 if (!parameters
->options().omagic()
984 && ((*p
)->flags() & elfcpp::PF_W
) != (seg_flags
& elfcpp::PF_W
))
986 // If -Tbss was specified, we need to separate the data and BSS
988 if (parameters
->options().user_set_Tbss())
990 if ((os
->type() == elfcpp::SHT_NOBITS
)
991 == (*p
)->has_any_data_sections())
994 if (os
->is_large_data_section() && !(*p
)->is_large_data_segment())
997 (*p
)->add_output_section(os
, seg_flags
);
1001 if (p
== this->segment_list_
.end())
1003 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_LOAD
,
1005 if (os
->is_large_data_section())
1006 oseg
->set_is_large_data_segment();
1007 oseg
->add_output_section(os
, seg_flags
);
1010 // If we see a loadable SHT_NOTE section, we create a PT_NOTE
1012 if (os
->type() == elfcpp::SHT_NOTE
)
1014 // See if we already have an equivalent PT_NOTE segment.
1015 for (p
= this->segment_list_
.begin();
1016 p
!= segment_list_
.end();
1019 if ((*p
)->type() == elfcpp::PT_NOTE
1020 && (((*p
)->flags() & elfcpp::PF_W
)
1021 == (seg_flags
& elfcpp::PF_W
)))
1023 (*p
)->add_output_section(os
, seg_flags
);
1028 if (p
== this->segment_list_
.end())
1030 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_NOTE
,
1032 oseg
->add_output_section(os
, seg_flags
);
1036 // If we see a loadable SHF_TLS section, we create a PT_TLS
1037 // segment. There can only be one such segment.
1038 if ((flags
& elfcpp::SHF_TLS
) != 0)
1040 if (this->tls_segment_
== NULL
)
1041 this->make_output_segment(elfcpp::PT_TLS
, seg_flags
);
1042 this->tls_segment_
->add_output_section(os
, seg_flags
);
1045 // If -z relro is in effect, and we see a relro section, we create a
1046 // PT_GNU_RELRO segment. There can only be one such segment.
1047 if (os
->is_relro() && parameters
->options().relro())
1049 gold_assert(seg_flags
== (elfcpp::PF_R
| elfcpp::PF_W
));
1050 if (this->relro_segment_
== NULL
)
1051 this->make_output_segment(elfcpp::PT_GNU_RELRO
, seg_flags
);
1052 this->relro_segment_
->add_output_section(os
, seg_flags
);
1056 // Make an output section for a script.
1059 Layout::make_output_section_for_script(const char* name
)
1061 name
= this->namepool_
.add(name
, false, NULL
);
1062 Output_section
* os
= this->make_output_section(name
, elfcpp::SHT_PROGBITS
,
1064 os
->set_found_in_sections_clause();
1068 // Return the number of segments we expect to see.
1071 Layout::expected_segment_count() const
1073 size_t ret
= this->segment_list_
.size();
1075 // If we didn't see a SECTIONS clause in a linker script, we should
1076 // already have the complete list of segments. Otherwise we ask the
1077 // SECTIONS clause how many segments it expects, and add in the ones
1078 // we already have (PT_GNU_STACK, PT_GNU_EH_FRAME, etc.)
1080 if (!this->script_options_
->saw_sections_clause())
1084 const Script_sections
* ss
= this->script_options_
->script_sections();
1085 return ret
+ ss
->expected_segment_count(this);
1089 // Handle the .note.GNU-stack section at layout time. SEEN_GNU_STACK
1090 // is whether we saw a .note.GNU-stack section in the object file.
1091 // GNU_STACK_FLAGS is the section flags. The flags give the
1092 // protection required for stack memory. We record this in an
1093 // executable as a PT_GNU_STACK segment. If an object file does not
1094 // have a .note.GNU-stack segment, we must assume that it is an old
1095 // object. On some targets that will force an executable stack.
1098 Layout::layout_gnu_stack(bool seen_gnu_stack
, uint64_t gnu_stack_flags
)
1100 if (!seen_gnu_stack
)
1101 this->input_without_gnu_stack_note_
= true;
1104 this->input_with_gnu_stack_note_
= true;
1105 if ((gnu_stack_flags
& elfcpp::SHF_EXECINSTR
) != 0)
1106 this->input_requires_executable_stack_
= true;
1110 // Create automatic note sections.
1113 Layout::create_notes()
1115 this->create_gold_note();
1116 this->create_executable_stack_info();
1117 this->create_build_id();
1120 // Create the dynamic sections which are needed before we read the
1124 Layout::create_initial_dynamic_sections(Symbol_table
* symtab
)
1126 if (parameters
->doing_static_link())
1129 this->dynamic_section_
= this->choose_output_section(NULL
, ".dynamic",
1130 elfcpp::SHT_DYNAMIC
,
1132 | elfcpp::SHF_WRITE
),
1134 this->dynamic_section_
->set_is_relro();
1136 symtab
->define_in_output_data("_DYNAMIC", NULL
, this->dynamic_section_
, 0, 0,
1137 elfcpp::STT_OBJECT
, elfcpp::STB_LOCAL
,
1138 elfcpp::STV_HIDDEN
, 0, false, false);
1140 this->dynamic_data_
= new Output_data_dynamic(&this->dynpool_
);
1142 this->dynamic_section_
->add_output_section_data(this->dynamic_data_
);
1145 // For each output section whose name can be represented as C symbol,
1146 // define __start and __stop symbols for the section. This is a GNU
1150 Layout::define_section_symbols(Symbol_table
* symtab
)
1152 for (Section_list::const_iterator p
= this->section_list_
.begin();
1153 p
!= this->section_list_
.end();
1156 const char* const name
= (*p
)->name();
1157 if (name
[strspn(name
,
1159 "ABCDEFGHIJKLMNOPWRSTUVWXYZ"
1160 "abcdefghijklmnopqrstuvwxyz"
1164 const std::string
name_string(name
);
1165 const std::string
start_name("__start_" + name_string
);
1166 const std::string
stop_name("__stop_" + name_string
);
1168 symtab
->define_in_output_data(start_name
.c_str(),
1175 elfcpp::STV_DEFAULT
,
1177 false, // offset_is_from_end
1178 true); // only_if_ref
1180 symtab
->define_in_output_data(stop_name
.c_str(),
1187 elfcpp::STV_DEFAULT
,
1189 true, // offset_is_from_end
1190 true); // only_if_ref
1195 // Define symbols for group signatures.
1198 Layout::define_group_signatures(Symbol_table
* symtab
)
1200 for (Group_signatures::iterator p
= this->group_signatures_
.begin();
1201 p
!= this->group_signatures_
.end();
1204 Symbol
* sym
= symtab
->lookup(p
->signature
, NULL
);
1206 p
->section
->set_info_symndx(sym
);
1209 // Force the name of the group section to the group
1210 // signature, and use the group's section symbol as the
1211 // signature symbol.
1212 if (strcmp(p
->section
->name(), p
->signature
) != 0)
1214 const char* name
= this->namepool_
.add(p
->signature
,
1216 p
->section
->set_name(name
);
1218 p
->section
->set_needs_symtab_index();
1219 p
->section
->set_info_section_symndx(p
->section
);
1223 this->group_signatures_
.clear();
1226 // Find the first read-only PT_LOAD segment, creating one if
1230 Layout::find_first_load_seg()
1232 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
1233 p
!= this->segment_list_
.end();
1236 if ((*p
)->type() == elfcpp::PT_LOAD
1237 && ((*p
)->flags() & elfcpp::PF_R
) != 0
1238 && (parameters
->options().omagic()
1239 || ((*p
)->flags() & elfcpp::PF_W
) == 0))
1243 gold_assert(!this->script_options_
->saw_phdrs_clause());
1245 Output_segment
* load_seg
= this->make_output_segment(elfcpp::PT_LOAD
,
1250 // Save states of all current output segments. Store saved states
1251 // in SEGMENT_STATES.
1254 Layout::save_segments(Segment_states
* segment_states
)
1256 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
1257 p
!= this->segment_list_
.end();
1260 Output_segment
* segment
= *p
;
1262 Output_segment
* copy
= new Output_segment(*segment
);
1263 (*segment_states
)[segment
] = copy
;
1267 // Restore states of output segments and delete any segment not found in
1271 Layout::restore_segments(const Segment_states
* segment_states
)
1273 // Go through the segment list and remove any segment added in the
1275 this->tls_segment_
= NULL
;
1276 this->relro_segment_
= NULL
;
1277 Segment_list::iterator list_iter
= this->segment_list_
.begin();
1278 while (list_iter
!= this->segment_list_
.end())
1280 Output_segment
* segment
= *list_iter
;
1281 Segment_states::const_iterator states_iter
=
1282 segment_states
->find(segment
);
1283 if (states_iter
!= segment_states
->end())
1285 const Output_segment
* copy
= states_iter
->second
;
1286 // Shallow copy to restore states.
1289 // Also fix up TLS and RELRO segment pointers as appropriate.
1290 if (segment
->type() == elfcpp::PT_TLS
)
1291 this->tls_segment_
= segment
;
1292 else if (segment
->type() == elfcpp::PT_GNU_RELRO
)
1293 this->relro_segment_
= segment
;
1299 list_iter
= this->segment_list_
.erase(list_iter
);
1300 // This is a segment created during section layout. It should be
1301 // safe to remove it since we should have removed all pointers to it.
1307 // Clean up after relaxation so that sections can be laid out again.
1310 Layout::clean_up_after_relaxation()
1312 // Restore the segments to point state just prior to the relaxation loop.
1313 Script_sections
* script_section
= this->script_options_
->script_sections();
1314 script_section
->release_segments();
1315 this->restore_segments(this->segment_states_
);
1317 // Reset section addresses and file offsets
1318 for (Section_list::iterator p
= this->section_list_
.begin();
1319 p
!= this->section_list_
.end();
1322 (*p
)->reset_address_and_file_offset();
1323 (*p
)->restore_states();
1326 // Reset special output object address and file offsets.
1327 for (Data_list::iterator p
= this->special_output_list_
.begin();
1328 p
!= this->special_output_list_
.end();
1330 (*p
)->reset_address_and_file_offset();
1332 // A linker script may have created some output section data objects.
1333 // They are useless now.
1334 for (Output_section_data_list::const_iterator p
=
1335 this->script_output_section_data_list_
.begin();
1336 p
!= this->script_output_section_data_list_
.end();
1339 this->script_output_section_data_list_
.clear();
1342 // Prepare for relaxation.
1345 Layout::prepare_for_relaxation()
1347 // Create an relaxation debug check if in debugging mode.
1348 if (is_debugging_enabled(DEBUG_RELAXATION
))
1349 this->relaxation_debug_check_
= new Relaxation_debug_check();
1351 // Save segment states.
1352 this->segment_states_
= new Segment_states();
1353 this->save_segments(this->segment_states_
);
1355 for(Section_list::const_iterator p
= this->section_list_
.begin();
1356 p
!= this->section_list_
.end();
1358 (*p
)->save_states();
1360 if (is_debugging_enabled(DEBUG_RELAXATION
))
1361 this->relaxation_debug_check_
->check_output_data_for_reset_values(
1362 this->section_list_
, this->special_output_list_
);
1364 // Also enable recording of output section data from scripts.
1365 this->record_output_section_data_from_script_
= true;
1368 // Relaxation loop body: If target has no relaxation, this runs only once
1369 // Otherwise, the target relaxation hook is called at the end of
1370 // each iteration. If the hook returns true, it means re-layout of
1371 // section is required.
1373 // The number of segments created by a linking script without a PHDRS
1374 // clause may be affected by section sizes and alignments. There is
1375 // a remote chance that relaxation causes different number of PT_LOAD
1376 // segments are created and sections are attached to different segments.
1377 // Therefore, we always throw away all segments created during section
1378 // layout. In order to be able to restart the section layout, we keep
1379 // a copy of the segment list right before the relaxation loop and use
1380 // that to restore the segments.
1382 // PASS is the current relaxation pass number.
1383 // SYMTAB is a symbol table.
1384 // PLOAD_SEG is the address of a pointer for the load segment.
1385 // PHDR_SEG is a pointer to the PHDR segment.
1386 // SEGMENT_HEADERS points to the output segment header.
1387 // FILE_HEADER points to the output file header.
1388 // PSHNDX is the address to store the output section index.
1391 Layout::relaxation_loop_body(
1394 Symbol_table
* symtab
,
1395 Output_segment
** pload_seg
,
1396 Output_segment
* phdr_seg
,
1397 Output_segment_headers
* segment_headers
,
1398 Output_file_header
* file_header
,
1399 unsigned int* pshndx
)
1401 // If this is not the first iteration, we need to clean up after
1402 // relaxation so that we can lay out the sections again.
1404 this->clean_up_after_relaxation();
1406 // If there is a SECTIONS clause, put all the input sections into
1407 // the required order.
1408 Output_segment
* load_seg
;
1409 if (this->script_options_
->saw_sections_clause())
1410 load_seg
= this->set_section_addresses_from_script(symtab
);
1411 else if (parameters
->options().relocatable())
1414 load_seg
= this->find_first_load_seg();
1416 if (parameters
->options().oformat_enum()
1417 != General_options::OBJECT_FORMAT_ELF
)
1420 gold_assert(phdr_seg
== NULL
|| load_seg
!= NULL
);
1422 // Lay out the segment headers.
1423 if (!parameters
->options().relocatable())
1425 gold_assert(segment_headers
!= NULL
);
1426 if (load_seg
!= NULL
)
1427 load_seg
->add_initial_output_data(segment_headers
);
1428 if (phdr_seg
!= NULL
)
1429 phdr_seg
->add_initial_output_data(segment_headers
);
1432 // Lay out the file header.
1433 if (load_seg
!= NULL
)
1434 load_seg
->add_initial_output_data(file_header
);
1436 if (this->script_options_
->saw_phdrs_clause()
1437 && !parameters
->options().relocatable())
1439 // Support use of FILEHDRS and PHDRS attachments in a PHDRS
1440 // clause in a linker script.
1441 Script_sections
* ss
= this->script_options_
->script_sections();
1442 ss
->put_headers_in_phdrs(file_header
, segment_headers
);
1445 // We set the output section indexes in set_segment_offsets and
1446 // set_section_indexes.
1449 // Set the file offsets of all the segments, and all the sections
1452 if (!parameters
->options().relocatable())
1453 off
= this->set_segment_offsets(target
, load_seg
, pshndx
);
1455 off
= this->set_relocatable_section_offsets(file_header
, pshndx
);
1457 // Verify that the dummy relaxation does not change anything.
1458 if (is_debugging_enabled(DEBUG_RELAXATION
))
1461 this->relaxation_debug_check_
->read_sections(this->section_list_
);
1463 this->relaxation_debug_check_
->verify_sections(this->section_list_
);
1466 *pload_seg
= load_seg
;
1470 // Finalize the layout. When this is called, we have created all the
1471 // output sections and all the output segments which are based on
1472 // input sections. We have several things to do, and we have to do
1473 // them in the right order, so that we get the right results correctly
1476 // 1) Finalize the list of output segments and create the segment
1479 // 2) Finalize the dynamic symbol table and associated sections.
1481 // 3) Determine the final file offset of all the output segments.
1483 // 4) Determine the final file offset of all the SHF_ALLOC output
1486 // 5) Create the symbol table sections and the section name table
1489 // 6) Finalize the symbol table: set symbol values to their final
1490 // value and make a final determination of which symbols are going
1491 // into the output symbol table.
1493 // 7) Create the section table header.
1495 // 8) Determine the final file offset of all the output sections which
1496 // are not SHF_ALLOC, including the section table header.
1498 // 9) Finalize the ELF file header.
1500 // This function returns the size of the output file.
1503 Layout::finalize(const Input_objects
* input_objects
, Symbol_table
* symtab
,
1504 Target
* target
, const Task
* task
)
1506 target
->finalize_sections(this);
1508 this->count_local_symbols(task
, input_objects
);
1510 this->link_stabs_sections();
1512 Output_segment
* phdr_seg
= NULL
;
1513 if (!parameters
->options().relocatable() && !parameters
->doing_static_link())
1515 // There was a dynamic object in the link. We need to create
1516 // some information for the dynamic linker.
1518 // Create the PT_PHDR segment which will hold the program
1520 if (!this->script_options_
->saw_phdrs_clause())
1521 phdr_seg
= this->make_output_segment(elfcpp::PT_PHDR
, elfcpp::PF_R
);
1523 // Create the dynamic symbol table, including the hash table.
1524 Output_section
* dynstr
;
1525 std::vector
<Symbol
*> dynamic_symbols
;
1526 unsigned int local_dynamic_count
;
1527 Versions
versions(*this->script_options()->version_script_info(),
1529 this->create_dynamic_symtab(input_objects
, symtab
, &dynstr
,
1530 &local_dynamic_count
, &dynamic_symbols
,
1533 // Create the .interp section to hold the name of the
1534 // interpreter, and put it in a PT_INTERP segment.
1535 if (!parameters
->options().shared())
1536 this->create_interp(target
);
1538 // Finish the .dynamic section to hold the dynamic data, and put
1539 // it in a PT_DYNAMIC segment.
1540 this->finish_dynamic_section(input_objects
, symtab
);
1542 // We should have added everything we need to the dynamic string
1544 this->dynpool_
.set_string_offsets();
1546 // Create the version sections. We can't do this until the
1547 // dynamic string table is complete.
1548 this->create_version_sections(&versions
, symtab
, local_dynamic_count
,
1549 dynamic_symbols
, dynstr
);
1552 if (this->incremental_inputs_
)
1554 this->incremental_inputs_
->finalize();
1555 this->create_incremental_info_sections();
1558 // Create segment headers.
1559 Output_segment_headers
* segment_headers
=
1560 (parameters
->options().relocatable()
1562 : new Output_segment_headers(this->segment_list_
));
1564 // Lay out the file header.
1565 Output_file_header
* file_header
1566 = new Output_file_header(target
, symtab
, segment_headers
,
1567 parameters
->options().entry());
1569 this->special_output_list_
.push_back(file_header
);
1570 if (segment_headers
!= NULL
)
1571 this->special_output_list_
.push_back(segment_headers
);
1573 // Find approriate places for orphan output sections if we are using
1575 if (this->script_options_
->saw_sections_clause())
1576 this->place_orphan_sections_in_script();
1578 Output_segment
* load_seg
;
1583 // Take a snapshot of the section layout as needed.
1584 if (target
->may_relax())
1585 this->prepare_for_relaxation();
1587 // Run the relaxation loop to lay out sections.
1590 off
= this->relaxation_loop_body(pass
, target
, symtab
, &load_seg
,
1591 phdr_seg
, segment_headers
, file_header
,
1595 while (target
->may_relax() && target
->relax(pass
));
1597 // Set the file offsets of all the non-data sections we've seen so
1598 // far which don't have to wait for the input sections. We need
1599 // this in order to finalize local symbols in non-allocated
1601 off
= this->set_section_offsets(off
, BEFORE_INPUT_SECTIONS_PASS
);
1603 // Set the section indexes of all unallocated sections seen so far,
1604 // in case any of them are somehow referenced by a symbol.
1605 shndx
= this->set_section_indexes(shndx
);
1607 // Create the symbol table sections.
1608 this->create_symtab_sections(input_objects
, symtab
, shndx
, &off
);
1609 if (!parameters
->doing_static_link())
1610 this->assign_local_dynsym_offsets(input_objects
);
1612 // Process any symbol assignments from a linker script. This must
1613 // be called after the symbol table has been finalized.
1614 this->script_options_
->finalize_symbols(symtab
, this);
1616 // Create the .shstrtab section.
1617 Output_section
* shstrtab_section
= this->create_shstrtab();
1619 // Set the file offsets of the rest of the non-data sections which
1620 // don't have to wait for the input sections.
1621 off
= this->set_section_offsets(off
, BEFORE_INPUT_SECTIONS_PASS
);
1623 // Now that all sections have been created, set the section indexes
1624 // for any sections which haven't been done yet.
1625 shndx
= this->set_section_indexes(shndx
);
1627 // Create the section table header.
1628 this->create_shdrs(shstrtab_section
, &off
);
1630 // If there are no sections which require postprocessing, we can
1631 // handle the section names now, and avoid a resize later.
1632 if (!this->any_postprocessing_sections_
)
1633 off
= this->set_section_offsets(off
,
1634 STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
);
1636 file_header
->set_section_info(this->section_headers_
, shstrtab_section
);
1638 // Now we know exactly where everything goes in the output file
1639 // (except for non-allocated sections which require postprocessing).
1640 Output_data::layout_complete();
1642 this->output_file_size_
= off
;
1647 // Create a note header following the format defined in the ELF ABI.
1648 // NAME is the name, NOTE_TYPE is the type, SECTION_NAME is the name
1649 // of the section to create, DESCSZ is the size of the descriptor.
1650 // ALLOCATE is true if the section should be allocated in memory.
1651 // This returns the new note section. It sets *TRAILING_PADDING to
1652 // the number of trailing zero bytes required.
1655 Layout::create_note(const char* name
, int note_type
,
1656 const char* section_name
, size_t descsz
,
1657 bool allocate
, size_t* trailing_padding
)
1659 // Authorities all agree that the values in a .note field should
1660 // be aligned on 4-byte boundaries for 32-bit binaries. However,
1661 // they differ on what the alignment is for 64-bit binaries.
1662 // The GABI says unambiguously they take 8-byte alignment:
1663 // http://sco.com/developers/gabi/latest/ch5.pheader.html#note_section
1664 // Other documentation says alignment should always be 4 bytes:
1665 // http://www.netbsd.org/docs/kernel/elf-notes.html#note-format
1666 // GNU ld and GNU readelf both support the latter (at least as of
1667 // version 2.16.91), and glibc always generates the latter for
1668 // .note.ABI-tag (as of version 1.6), so that's the one we go with
1670 #ifdef GABI_FORMAT_FOR_DOTNOTE_SECTION // This is not defined by default.
1671 const int size
= parameters
->target().get_size();
1673 const int size
= 32;
1676 // The contents of the .note section.
1677 size_t namesz
= strlen(name
) + 1;
1678 size_t aligned_namesz
= align_address(namesz
, size
/ 8);
1679 size_t aligned_descsz
= align_address(descsz
, size
/ 8);
1681 size_t notehdrsz
= 3 * (size
/ 8) + aligned_namesz
;
1683 unsigned char* buffer
= new unsigned char[notehdrsz
];
1684 memset(buffer
, 0, notehdrsz
);
1686 bool is_big_endian
= parameters
->target().is_big_endian();
1692 elfcpp::Swap
<32, false>::writeval(buffer
, namesz
);
1693 elfcpp::Swap
<32, false>::writeval(buffer
+ 4, descsz
);
1694 elfcpp::Swap
<32, false>::writeval(buffer
+ 8, note_type
);
1698 elfcpp::Swap
<32, true>::writeval(buffer
, namesz
);
1699 elfcpp::Swap
<32, true>::writeval(buffer
+ 4, descsz
);
1700 elfcpp::Swap
<32, true>::writeval(buffer
+ 8, note_type
);
1703 else if (size
== 64)
1707 elfcpp::Swap
<64, false>::writeval(buffer
, namesz
);
1708 elfcpp::Swap
<64, false>::writeval(buffer
+ 8, descsz
);
1709 elfcpp::Swap
<64, false>::writeval(buffer
+ 16, note_type
);
1713 elfcpp::Swap
<64, true>::writeval(buffer
, namesz
);
1714 elfcpp::Swap
<64, true>::writeval(buffer
+ 8, descsz
);
1715 elfcpp::Swap
<64, true>::writeval(buffer
+ 16, note_type
);
1721 memcpy(buffer
+ 3 * (size
/ 8), name
, namesz
);
1723 elfcpp::Elf_Xword flags
= 0;
1725 flags
= elfcpp::SHF_ALLOC
;
1726 Output_section
* os
= this->choose_output_section(NULL
, section_name
,
1732 Output_section_data
* posd
= new Output_data_const_buffer(buffer
, notehdrsz
,
1735 os
->add_output_section_data(posd
);
1737 *trailing_padding
= aligned_descsz
- descsz
;
1742 // For an executable or shared library, create a note to record the
1743 // version of gold used to create the binary.
1746 Layout::create_gold_note()
1748 if (parameters
->options().relocatable())
1751 std::string desc
= std::string("gold ") + gold::get_version_string();
1753 size_t trailing_padding
;
1754 Output_section
*os
= this->create_note("GNU", elfcpp::NT_GNU_GOLD_VERSION
,
1755 ".note.gnu.gold-version", desc
.size(),
1756 false, &trailing_padding
);
1760 Output_section_data
* posd
= new Output_data_const(desc
, 4);
1761 os
->add_output_section_data(posd
);
1763 if (trailing_padding
> 0)
1765 posd
= new Output_data_zero_fill(trailing_padding
, 0);
1766 os
->add_output_section_data(posd
);
1770 // Record whether the stack should be executable. This can be set
1771 // from the command line using the -z execstack or -z noexecstack
1772 // options. Otherwise, if any input file has a .note.GNU-stack
1773 // section with the SHF_EXECINSTR flag set, the stack should be
1774 // executable. Otherwise, if at least one input file a
1775 // .note.GNU-stack section, and some input file has no .note.GNU-stack
1776 // section, we use the target default for whether the stack should be
1777 // executable. Otherwise, we don't generate a stack note. When
1778 // generating a object file, we create a .note.GNU-stack section with
1779 // the appropriate marking. When generating an executable or shared
1780 // library, we create a PT_GNU_STACK segment.
1783 Layout::create_executable_stack_info()
1785 bool is_stack_executable
;
1786 if (parameters
->options().is_execstack_set())
1787 is_stack_executable
= parameters
->options().is_stack_executable();
1788 else if (!this->input_with_gnu_stack_note_
)
1792 if (this->input_requires_executable_stack_
)
1793 is_stack_executable
= true;
1794 else if (this->input_without_gnu_stack_note_
)
1795 is_stack_executable
=
1796 parameters
->target().is_default_stack_executable();
1798 is_stack_executable
= false;
1801 if (parameters
->options().relocatable())
1803 const char* name
= this->namepool_
.add(".note.GNU-stack", false, NULL
);
1804 elfcpp::Elf_Xword flags
= 0;
1805 if (is_stack_executable
)
1806 flags
|= elfcpp::SHF_EXECINSTR
;
1807 this->make_output_section(name
, elfcpp::SHT_PROGBITS
, flags
);
1811 if (this->script_options_
->saw_phdrs_clause())
1813 int flags
= elfcpp::PF_R
| elfcpp::PF_W
;
1814 if (is_stack_executable
)
1815 flags
|= elfcpp::PF_X
;
1816 this->make_output_segment(elfcpp::PT_GNU_STACK
, flags
);
1820 // If --build-id was used, set up the build ID note.
1823 Layout::create_build_id()
1825 if (!parameters
->options().user_set_build_id())
1828 const char* style
= parameters
->options().build_id();
1829 if (strcmp(style
, "none") == 0)
1832 // Set DESCSZ to the size of the note descriptor. When possible,
1833 // set DESC to the note descriptor contents.
1836 if (strcmp(style
, "md5") == 0)
1838 else if (strcmp(style
, "sha1") == 0)
1840 else if (strcmp(style
, "uuid") == 0)
1842 const size_t uuidsz
= 128 / 8;
1844 char buffer
[uuidsz
];
1845 memset(buffer
, 0, uuidsz
);
1847 int descriptor
= open_descriptor(-1, "/dev/urandom", O_RDONLY
);
1849 gold_error(_("--build-id=uuid failed: could not open /dev/urandom: %s"),
1853 ssize_t got
= ::read(descriptor
, buffer
, uuidsz
);
1854 release_descriptor(descriptor
, true);
1856 gold_error(_("/dev/urandom: read failed: %s"), strerror(errno
));
1857 else if (static_cast<size_t>(got
) != uuidsz
)
1858 gold_error(_("/dev/urandom: expected %zu bytes, got %zd bytes"),
1862 desc
.assign(buffer
, uuidsz
);
1865 else if (strncmp(style
, "0x", 2) == 0)
1868 const char* p
= style
+ 2;
1871 if (hex_p(p
[0]) && hex_p(p
[1]))
1873 char c
= (hex_value(p
[0]) << 4) | hex_value(p
[1]);
1877 else if (*p
== '-' || *p
== ':')
1880 gold_fatal(_("--build-id argument '%s' not a valid hex number"),
1883 descsz
= desc
.size();
1886 gold_fatal(_("unrecognized --build-id argument '%s'"), style
);
1889 size_t trailing_padding
;
1890 Output_section
* os
= this->create_note("GNU", elfcpp::NT_GNU_BUILD_ID
,
1891 ".note.gnu.build-id", descsz
, true,
1898 // We know the value already, so we fill it in now.
1899 gold_assert(desc
.size() == descsz
);
1901 Output_section_data
* posd
= new Output_data_const(desc
, 4);
1902 os
->add_output_section_data(posd
);
1904 if (trailing_padding
!= 0)
1906 posd
= new Output_data_zero_fill(trailing_padding
, 0);
1907 os
->add_output_section_data(posd
);
1912 // We need to compute a checksum after we have completed the
1914 gold_assert(trailing_padding
== 0);
1915 this->build_id_note_
= new Output_data_zero_fill(descsz
, 4);
1916 os
->add_output_section_data(this->build_id_note_
);
1920 // If we have both .stabXX and .stabXXstr sections, then the sh_link
1921 // field of the former should point to the latter. I'm not sure who
1922 // started this, but the GNU linker does it, and some tools depend
1926 Layout::link_stabs_sections()
1928 if (!this->have_stabstr_section_
)
1931 for (Section_list::iterator p
= this->section_list_
.begin();
1932 p
!= this->section_list_
.end();
1935 if ((*p
)->type() != elfcpp::SHT_STRTAB
)
1938 const char* name
= (*p
)->name();
1939 if (strncmp(name
, ".stab", 5) != 0)
1942 size_t len
= strlen(name
);
1943 if (strcmp(name
+ len
- 3, "str") != 0)
1946 std::string
stab_name(name
, len
- 3);
1947 Output_section
* stab_sec
;
1948 stab_sec
= this->find_output_section(stab_name
.c_str());
1949 if (stab_sec
!= NULL
)
1950 stab_sec
->set_link_section(*p
);
1954 // Create .gnu_incremental_inputs and .gnu_incremental_strtab sections needed
1955 // for the next run of incremental linking to check what has changed.
1958 Layout::create_incremental_info_sections()
1960 gold_assert(this->incremental_inputs_
!= NULL
);
1962 // Add the .gnu_incremental_inputs section.
1963 const char *incremental_inputs_name
=
1964 this->namepool_
.add(".gnu_incremental_inputs", false, NULL
);
1965 Output_section
* inputs_os
=
1966 this->make_output_section(incremental_inputs_name
,
1967 elfcpp::SHT_GNU_INCREMENTAL_INPUTS
, 0);
1968 Output_section_data
* posd
=
1969 this->incremental_inputs_
->create_incremental_inputs_section_data();
1970 inputs_os
->add_output_section_data(posd
);
1972 // Add the .gnu_incremental_strtab section.
1973 const char *incremental_strtab_name
=
1974 this->namepool_
.add(".gnu_incremental_strtab", false, NULL
);
1975 Output_section
* strtab_os
= this->make_output_section(incremental_strtab_name
,
1978 Output_data_strtab
* strtab_data
=
1979 new Output_data_strtab(this->incremental_inputs_
->get_stringpool());
1980 strtab_os
->add_output_section_data(strtab_data
);
1982 inputs_os
->set_link_section(strtab_data
);
1985 // Return whether SEG1 should be before SEG2 in the output file. This
1986 // is based entirely on the segment type and flags. When this is
1987 // called the segment addresses has normally not yet been set.
1990 Layout::segment_precedes(const Output_segment
* seg1
,
1991 const Output_segment
* seg2
)
1993 elfcpp::Elf_Word type1
= seg1
->type();
1994 elfcpp::Elf_Word type2
= seg2
->type();
1996 // The single PT_PHDR segment is required to precede any loadable
1997 // segment. We simply make it always first.
1998 if (type1
== elfcpp::PT_PHDR
)
2000 gold_assert(type2
!= elfcpp::PT_PHDR
);
2003 if (type2
== elfcpp::PT_PHDR
)
2006 // The single PT_INTERP segment is required to precede any loadable
2007 // segment. We simply make it always second.
2008 if (type1
== elfcpp::PT_INTERP
)
2010 gold_assert(type2
!= elfcpp::PT_INTERP
);
2013 if (type2
== elfcpp::PT_INTERP
)
2016 // We then put PT_LOAD segments before any other segments.
2017 if (type1
== elfcpp::PT_LOAD
&& type2
!= elfcpp::PT_LOAD
)
2019 if (type2
== elfcpp::PT_LOAD
&& type1
!= elfcpp::PT_LOAD
)
2022 // We put the PT_TLS segment last except for the PT_GNU_RELRO
2023 // segment, because that is where the dynamic linker expects to find
2024 // it (this is just for efficiency; other positions would also work
2026 if (type1
== elfcpp::PT_TLS
2027 && type2
!= elfcpp::PT_TLS
2028 && type2
!= elfcpp::PT_GNU_RELRO
)
2030 if (type2
== elfcpp::PT_TLS
2031 && type1
!= elfcpp::PT_TLS
2032 && type1
!= elfcpp::PT_GNU_RELRO
)
2035 // We put the PT_GNU_RELRO segment last, because that is where the
2036 // dynamic linker expects to find it (as with PT_TLS, this is just
2038 if (type1
== elfcpp::PT_GNU_RELRO
&& type2
!= elfcpp::PT_GNU_RELRO
)
2040 if (type2
== elfcpp::PT_GNU_RELRO
&& type1
!= elfcpp::PT_GNU_RELRO
)
2043 const elfcpp::Elf_Word flags1
= seg1
->flags();
2044 const elfcpp::Elf_Word flags2
= seg2
->flags();
2046 // The order of non-PT_LOAD segments is unimportant. We simply sort
2047 // by the numeric segment type and flags values. There should not
2048 // be more than one segment with the same type and flags.
2049 if (type1
!= elfcpp::PT_LOAD
)
2052 return type1
< type2
;
2053 gold_assert(flags1
!= flags2
);
2054 return flags1
< flags2
;
2057 // If the addresses are set already, sort by load address.
2058 if (seg1
->are_addresses_set())
2060 if (!seg2
->are_addresses_set())
2063 unsigned int section_count1
= seg1
->output_section_count();
2064 unsigned int section_count2
= seg2
->output_section_count();
2065 if (section_count1
== 0 && section_count2
> 0)
2067 if (section_count1
> 0 && section_count2
== 0)
2070 uint64_t paddr1
= seg1
->first_section_load_address();
2071 uint64_t paddr2
= seg2
->first_section_load_address();
2072 if (paddr1
!= paddr2
)
2073 return paddr1
< paddr2
;
2075 else if (seg2
->are_addresses_set())
2078 // A segment which holds large data comes after a segment which does
2079 // not hold large data.
2080 if (seg1
->is_large_data_segment())
2082 if (!seg2
->is_large_data_segment())
2085 else if (seg2
->is_large_data_segment())
2088 // Otherwise, we sort PT_LOAD segments based on the flags. Readonly
2089 // segments come before writable segments. Then writable segments
2090 // with data come before writable segments without data. Then
2091 // executable segments come before non-executable segments. Then
2092 // the unlikely case of a non-readable segment comes before the
2093 // normal case of a readable segment. If there are multiple
2094 // segments with the same type and flags, we require that the
2095 // address be set, and we sort by virtual address and then physical
2097 if ((flags1
& elfcpp::PF_W
) != (flags2
& elfcpp::PF_W
))
2098 return (flags1
& elfcpp::PF_W
) == 0;
2099 if ((flags1
& elfcpp::PF_W
) != 0
2100 && seg1
->has_any_data_sections() != seg2
->has_any_data_sections())
2101 return seg1
->has_any_data_sections();
2102 if ((flags1
& elfcpp::PF_X
) != (flags2
& elfcpp::PF_X
))
2103 return (flags1
& elfcpp::PF_X
) != 0;
2104 if ((flags1
& elfcpp::PF_R
) != (flags2
& elfcpp::PF_R
))
2105 return (flags1
& elfcpp::PF_R
) == 0;
2107 // We shouldn't get here--we shouldn't create segments which we
2108 // can't distinguish.
2112 // Increase OFF so that it is congruent to ADDR modulo ABI_PAGESIZE.
2115 align_file_offset(off_t off
, uint64_t addr
, uint64_t abi_pagesize
)
2117 uint64_t unsigned_off
= off
;
2118 uint64_t aligned_off
= ((unsigned_off
& ~(abi_pagesize
- 1))
2119 | (addr
& (abi_pagesize
- 1)));
2120 if (aligned_off
< unsigned_off
)
2121 aligned_off
+= abi_pagesize
;
2125 // Set the file offsets of all the segments, and all the sections they
2126 // contain. They have all been created. LOAD_SEG must be be laid out
2127 // first. Return the offset of the data to follow.
2130 Layout::set_segment_offsets(const Target
* target
, Output_segment
* load_seg
,
2131 unsigned int *pshndx
)
2133 // Sort them into the final order.
2134 std::sort(this->segment_list_
.begin(), this->segment_list_
.end(),
2135 Layout::Compare_segments());
2137 // Find the PT_LOAD segments, and set their addresses and offsets
2138 // and their section's addresses and offsets.
2140 if (parameters
->options().user_set_Ttext())
2141 addr
= parameters
->options().Ttext();
2142 else if (parameters
->options().shared())
2145 addr
= target
->default_text_segment_address();
2148 // If LOAD_SEG is NULL, then the file header and segment headers
2149 // will not be loadable. But they still need to be at offset 0 in
2150 // the file. Set their offsets now.
2151 if (load_seg
== NULL
)
2153 for (Data_list::iterator p
= this->special_output_list_
.begin();
2154 p
!= this->special_output_list_
.end();
2157 off
= align_address(off
, (*p
)->addralign());
2158 (*p
)->set_address_and_file_offset(0, off
);
2159 off
+= (*p
)->data_size();
2163 const bool check_sections
= parameters
->options().check_sections();
2164 Output_segment
* last_load_segment
= NULL
;
2166 bool was_readonly
= false;
2167 for (Segment_list::iterator p
= this->segment_list_
.begin();
2168 p
!= this->segment_list_
.end();
2171 if ((*p
)->type() == elfcpp::PT_LOAD
)
2173 if (load_seg
!= NULL
&& load_seg
!= *p
)
2177 bool are_addresses_set
= (*p
)->are_addresses_set();
2178 if (are_addresses_set
)
2180 // When it comes to setting file offsets, we care about
2181 // the physical address.
2182 addr
= (*p
)->paddr();
2184 else if (parameters
->options().user_set_Tdata()
2185 && ((*p
)->flags() & elfcpp::PF_W
) != 0
2186 && (!parameters
->options().user_set_Tbss()
2187 || (*p
)->has_any_data_sections()))
2189 addr
= parameters
->options().Tdata();
2190 are_addresses_set
= true;
2192 else if (parameters
->options().user_set_Tbss()
2193 && ((*p
)->flags() & elfcpp::PF_W
) != 0
2194 && !(*p
)->has_any_data_sections())
2196 addr
= parameters
->options().Tbss();
2197 are_addresses_set
= true;
2200 uint64_t orig_addr
= addr
;
2201 uint64_t orig_off
= off
;
2203 uint64_t aligned_addr
= 0;
2204 uint64_t abi_pagesize
= target
->abi_pagesize();
2205 uint64_t common_pagesize
= target
->common_pagesize();
2207 if (!parameters
->options().nmagic()
2208 && !parameters
->options().omagic())
2209 (*p
)->set_minimum_p_align(common_pagesize
);
2211 if (!are_addresses_set
)
2213 // If the last segment was readonly, and this one is
2214 // not, then skip the address forward one page,
2215 // maintaining the same position within the page. This
2216 // lets us store both segments overlapping on a single
2217 // page in the file, but the loader will put them on
2218 // different pages in memory.
2220 addr
= align_address(addr
, (*p
)->maximum_alignment());
2221 aligned_addr
= addr
;
2223 if (was_readonly
&& ((*p
)->flags() & elfcpp::PF_W
) != 0)
2225 if ((addr
& (abi_pagesize
- 1)) != 0)
2226 addr
= addr
+ abi_pagesize
;
2229 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
2232 if (!parameters
->options().nmagic()
2233 && !parameters
->options().omagic())
2234 off
= align_file_offset(off
, addr
, abi_pagesize
);
2236 unsigned int shndx_hold
= *pshndx
;
2237 uint64_t new_addr
= (*p
)->set_section_addresses(this, false, addr
,
2240 // Now that we know the size of this segment, we may be able
2241 // to save a page in memory, at the cost of wasting some
2242 // file space, by instead aligning to the start of a new
2243 // page. Here we use the real machine page size rather than
2244 // the ABI mandated page size.
2246 if (!are_addresses_set
&& aligned_addr
!= addr
)
2248 uint64_t first_off
= (common_pagesize
2250 & (common_pagesize
- 1)));
2251 uint64_t last_off
= new_addr
& (common_pagesize
- 1);
2254 && ((aligned_addr
& ~ (common_pagesize
- 1))
2255 != (new_addr
& ~ (common_pagesize
- 1)))
2256 && first_off
+ last_off
<= common_pagesize
)
2258 *pshndx
= shndx_hold
;
2259 addr
= align_address(aligned_addr
, common_pagesize
);
2260 addr
= align_address(addr
, (*p
)->maximum_alignment());
2261 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
2262 off
= align_file_offset(off
, addr
, abi_pagesize
);
2263 new_addr
= (*p
)->set_section_addresses(this, true, addr
,
2270 if (((*p
)->flags() & elfcpp::PF_W
) == 0)
2271 was_readonly
= true;
2273 // Implement --check-sections. We know that the segments
2274 // are sorted by LMA.
2275 if (check_sections
&& last_load_segment
!= NULL
)
2277 gold_assert(last_load_segment
->paddr() <= (*p
)->paddr());
2278 if (last_load_segment
->paddr() + last_load_segment
->memsz()
2281 unsigned long long lb1
= last_load_segment
->paddr();
2282 unsigned long long le1
= lb1
+ last_load_segment
->memsz();
2283 unsigned long long lb2
= (*p
)->paddr();
2284 unsigned long long le2
= lb2
+ (*p
)->memsz();
2285 gold_error(_("load segment overlap [0x%llx -> 0x%llx] and "
2286 "[0x%llx -> 0x%llx]"),
2287 lb1
, le1
, lb2
, le2
);
2290 last_load_segment
= *p
;
2294 // Handle the non-PT_LOAD segments, setting their offsets from their
2295 // section's offsets.
2296 for (Segment_list::iterator p
= this->segment_list_
.begin();
2297 p
!= this->segment_list_
.end();
2300 if ((*p
)->type() != elfcpp::PT_LOAD
)
2304 // Set the TLS offsets for each section in the PT_TLS segment.
2305 if (this->tls_segment_
!= NULL
)
2306 this->tls_segment_
->set_tls_offsets();
2311 // Set the offsets of all the allocated sections when doing a
2312 // relocatable link. This does the same jobs as set_segment_offsets,
2313 // only for a relocatable link.
2316 Layout::set_relocatable_section_offsets(Output_data
* file_header
,
2317 unsigned int *pshndx
)
2321 file_header
->set_address_and_file_offset(0, 0);
2322 off
+= file_header
->data_size();
2324 for (Section_list::iterator p
= this->section_list_
.begin();
2325 p
!= this->section_list_
.end();
2328 // We skip unallocated sections here, except that group sections
2329 // have to come first.
2330 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) == 0
2331 && (*p
)->type() != elfcpp::SHT_GROUP
)
2334 off
= align_address(off
, (*p
)->addralign());
2336 // The linker script might have set the address.
2337 if (!(*p
)->is_address_valid())
2338 (*p
)->set_address(0);
2339 (*p
)->set_file_offset(off
);
2340 (*p
)->finalize_data_size();
2341 off
+= (*p
)->data_size();
2343 (*p
)->set_out_shndx(*pshndx
);
2350 // Set the file offset of all the sections not associated with a
2354 Layout::set_section_offsets(off_t off
, Layout::Section_offset_pass pass
)
2356 for (Section_list::iterator p
= this->unattached_section_list_
.begin();
2357 p
!= this->unattached_section_list_
.end();
2360 // The symtab section is handled in create_symtab_sections.
2361 if (*p
== this->symtab_section_
)
2364 // If we've already set the data size, don't set it again.
2365 if ((*p
)->is_offset_valid() && (*p
)->is_data_size_valid())
2368 if (pass
== BEFORE_INPUT_SECTIONS_PASS
2369 && (*p
)->requires_postprocessing())
2371 (*p
)->create_postprocessing_buffer();
2372 this->any_postprocessing_sections_
= true;
2375 if (pass
== BEFORE_INPUT_SECTIONS_PASS
2376 && (*p
)->after_input_sections())
2378 else if (pass
== POSTPROCESSING_SECTIONS_PASS
2379 && (!(*p
)->after_input_sections()
2380 || (*p
)->type() == elfcpp::SHT_STRTAB
))
2382 else if (pass
== STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
2383 && (!(*p
)->after_input_sections()
2384 || (*p
)->type() != elfcpp::SHT_STRTAB
))
2387 off
= align_address(off
, (*p
)->addralign());
2388 (*p
)->set_file_offset(off
);
2389 (*p
)->finalize_data_size();
2390 off
+= (*p
)->data_size();
2392 // At this point the name must be set.
2393 if (pass
!= STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
)
2394 this->namepool_
.add((*p
)->name(), false, NULL
);
2399 // Set the section indexes of all the sections not associated with a
2403 Layout::set_section_indexes(unsigned int shndx
)
2405 for (Section_list::iterator p
= this->unattached_section_list_
.begin();
2406 p
!= this->unattached_section_list_
.end();
2409 if (!(*p
)->has_out_shndx())
2411 (*p
)->set_out_shndx(shndx
);
2418 // Set the section addresses according to the linker script. This is
2419 // only called when we see a SECTIONS clause. This returns the
2420 // program segment which should hold the file header and segment
2421 // headers, if any. It will return NULL if they should not be in a
2425 Layout::set_section_addresses_from_script(Symbol_table
* symtab
)
2427 Script_sections
* ss
= this->script_options_
->script_sections();
2428 gold_assert(ss
->saw_sections_clause());
2429 return this->script_options_
->set_section_addresses(symtab
, this);
2432 // Place the orphan sections in the linker script.
2435 Layout::place_orphan_sections_in_script()
2437 Script_sections
* ss
= this->script_options_
->script_sections();
2438 gold_assert(ss
->saw_sections_clause());
2440 // Place each orphaned output section in the script.
2441 for (Section_list::iterator p
= this->section_list_
.begin();
2442 p
!= this->section_list_
.end();
2445 if (!(*p
)->found_in_sections_clause())
2446 ss
->place_orphan(*p
);
2450 // Count the local symbols in the regular symbol table and the dynamic
2451 // symbol table, and build the respective string pools.
2454 Layout::count_local_symbols(const Task
* task
,
2455 const Input_objects
* input_objects
)
2457 // First, figure out an upper bound on the number of symbols we'll
2458 // be inserting into each pool. This helps us create the pools with
2459 // the right size, to avoid unnecessary hashtable resizing.
2460 unsigned int symbol_count
= 0;
2461 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
2462 p
!= input_objects
->relobj_end();
2464 symbol_count
+= (*p
)->local_symbol_count();
2466 // Go from "upper bound" to "estimate." We overcount for two
2467 // reasons: we double-count symbols that occur in more than one
2468 // object file, and we count symbols that are dropped from the
2469 // output. Add it all together and assume we overcount by 100%.
2472 // We assume all symbols will go into both the sympool and dynpool.
2473 this->sympool_
.reserve(symbol_count
);
2474 this->dynpool_
.reserve(symbol_count
);
2476 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
2477 p
!= input_objects
->relobj_end();
2480 Task_lock_obj
<Object
> tlo(task
, *p
);
2481 (*p
)->count_local_symbols(&this->sympool_
, &this->dynpool_
);
2485 // Create the symbol table sections. Here we also set the final
2486 // values of the symbols. At this point all the loadable sections are
2487 // fully laid out. SHNUM is the number of sections so far.
2490 Layout::create_symtab_sections(const Input_objects
* input_objects
,
2491 Symbol_table
* symtab
,
2497 if (parameters
->target().get_size() == 32)
2499 symsize
= elfcpp::Elf_sizes
<32>::sym_size
;
2502 else if (parameters
->target().get_size() == 64)
2504 symsize
= elfcpp::Elf_sizes
<64>::sym_size
;
2511 off
= align_address(off
, align
);
2512 off_t startoff
= off
;
2514 // Save space for the dummy symbol at the start of the section. We
2515 // never bother to write this out--it will just be left as zero.
2517 unsigned int local_symbol_index
= 1;
2519 // Add STT_SECTION symbols for each Output section which needs one.
2520 for (Section_list::iterator p
= this->section_list_
.begin();
2521 p
!= this->section_list_
.end();
2524 if (!(*p
)->needs_symtab_index())
2525 (*p
)->set_symtab_index(-1U);
2528 (*p
)->set_symtab_index(local_symbol_index
);
2529 ++local_symbol_index
;
2534 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
2535 p
!= input_objects
->relobj_end();
2538 unsigned int index
= (*p
)->finalize_local_symbols(local_symbol_index
,
2540 off
+= (index
- local_symbol_index
) * symsize
;
2541 local_symbol_index
= index
;
2544 unsigned int local_symcount
= local_symbol_index
;
2545 gold_assert(static_cast<off_t
>(local_symcount
* symsize
) == off
- startoff
);
2548 size_t dyn_global_index
;
2550 if (this->dynsym_section_
== NULL
)
2553 dyn_global_index
= 0;
2558 dyn_global_index
= this->dynsym_section_
->info();
2559 off_t locsize
= dyn_global_index
* this->dynsym_section_
->entsize();
2560 dynoff
= this->dynsym_section_
->offset() + locsize
;
2561 dyncount
= (this->dynsym_section_
->data_size() - locsize
) / symsize
;
2562 gold_assert(static_cast<off_t
>(dyncount
* symsize
)
2563 == this->dynsym_section_
->data_size() - locsize
);
2566 off
= symtab
->finalize(off
, dynoff
, dyn_global_index
, dyncount
,
2567 &this->sympool_
, &local_symcount
);
2569 if (!parameters
->options().strip_all())
2571 this->sympool_
.set_string_offsets();
2573 const char* symtab_name
= this->namepool_
.add(".symtab", false, NULL
);
2574 Output_section
* osymtab
= this->make_output_section(symtab_name
,
2577 this->symtab_section_
= osymtab
;
2579 Output_section_data
* pos
= new Output_data_fixed_space(off
- startoff
,
2582 osymtab
->add_output_section_data(pos
);
2584 // We generate a .symtab_shndx section if we have more than
2585 // SHN_LORESERVE sections. Technically it is possible that we
2586 // don't need one, because it is possible that there are no
2587 // symbols in any of sections with indexes larger than
2588 // SHN_LORESERVE. That is probably unusual, though, and it is
2589 // easier to always create one than to compute section indexes
2590 // twice (once here, once when writing out the symbols).
2591 if (shnum
>= elfcpp::SHN_LORESERVE
)
2593 const char* symtab_xindex_name
= this->namepool_
.add(".symtab_shndx",
2595 Output_section
* osymtab_xindex
=
2596 this->make_output_section(symtab_xindex_name
,
2597 elfcpp::SHT_SYMTAB_SHNDX
, 0);
2599 size_t symcount
= (off
- startoff
) / symsize
;
2600 this->symtab_xindex_
= new Output_symtab_xindex(symcount
);
2602 osymtab_xindex
->add_output_section_data(this->symtab_xindex_
);
2604 osymtab_xindex
->set_link_section(osymtab
);
2605 osymtab_xindex
->set_addralign(4);
2606 osymtab_xindex
->set_entsize(4);
2608 osymtab_xindex
->set_after_input_sections();
2610 // This tells the driver code to wait until the symbol table
2611 // has written out before writing out the postprocessing
2612 // sections, including the .symtab_shndx section.
2613 this->any_postprocessing_sections_
= true;
2616 const char* strtab_name
= this->namepool_
.add(".strtab", false, NULL
);
2617 Output_section
* ostrtab
= this->make_output_section(strtab_name
,
2621 Output_section_data
* pstr
= new Output_data_strtab(&this->sympool_
);
2622 ostrtab
->add_output_section_data(pstr
);
2624 osymtab
->set_file_offset(startoff
);
2625 osymtab
->finalize_data_size();
2626 osymtab
->set_link_section(ostrtab
);
2627 osymtab
->set_info(local_symcount
);
2628 osymtab
->set_entsize(symsize
);
2634 // Create the .shstrtab section, which holds the names of the
2635 // sections. At the time this is called, we have created all the
2636 // output sections except .shstrtab itself.
2639 Layout::create_shstrtab()
2641 // FIXME: We don't need to create a .shstrtab section if we are
2642 // stripping everything.
2644 const char* name
= this->namepool_
.add(".shstrtab", false, NULL
);
2646 Output_section
* os
= this->make_output_section(name
, elfcpp::SHT_STRTAB
, 0);
2648 // We can't write out this section until we've set all the section
2649 // names, and we don't set the names of compressed output sections
2650 // until relocations are complete.
2651 os
->set_after_input_sections();
2653 Output_section_data
* posd
= new Output_data_strtab(&this->namepool_
);
2654 os
->add_output_section_data(posd
);
2659 // Create the section headers. SIZE is 32 or 64. OFF is the file
2663 Layout::create_shdrs(const Output_section
* shstrtab_section
, off_t
* poff
)
2665 Output_section_headers
* oshdrs
;
2666 oshdrs
= new Output_section_headers(this,
2667 &this->segment_list_
,
2668 &this->section_list_
,
2669 &this->unattached_section_list_
,
2672 off_t off
= align_address(*poff
, oshdrs
->addralign());
2673 oshdrs
->set_address_and_file_offset(0, off
);
2674 off
+= oshdrs
->data_size();
2676 this->section_headers_
= oshdrs
;
2679 // Count the allocated sections.
2682 Layout::allocated_output_section_count() const
2684 size_t section_count
= 0;
2685 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
2686 p
!= this->segment_list_
.end();
2688 section_count
+= (*p
)->output_section_count();
2689 return section_count
;
2692 // Create the dynamic symbol table.
2695 Layout::create_dynamic_symtab(const Input_objects
* input_objects
,
2696 Symbol_table
* symtab
,
2697 Output_section
**pdynstr
,
2698 unsigned int* plocal_dynamic_count
,
2699 std::vector
<Symbol
*>* pdynamic_symbols
,
2700 Versions
* pversions
)
2702 // Count all the symbols in the dynamic symbol table, and set the
2703 // dynamic symbol indexes.
2705 // Skip symbol 0, which is always all zeroes.
2706 unsigned int index
= 1;
2708 // Add STT_SECTION symbols for each Output section which needs one.
2709 for (Section_list::iterator p
= this->section_list_
.begin();
2710 p
!= this->section_list_
.end();
2713 if (!(*p
)->needs_dynsym_index())
2714 (*p
)->set_dynsym_index(-1U);
2717 (*p
)->set_dynsym_index(index
);
2722 // Count the local symbols that need to go in the dynamic symbol table,
2723 // and set the dynamic symbol indexes.
2724 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
2725 p
!= input_objects
->relobj_end();
2728 unsigned int new_index
= (*p
)->set_local_dynsym_indexes(index
);
2732 unsigned int local_symcount
= index
;
2733 *plocal_dynamic_count
= local_symcount
;
2735 index
= symtab
->set_dynsym_indexes(index
, pdynamic_symbols
,
2736 &this->dynpool_
, pversions
);
2740 const int size
= parameters
->target().get_size();
2743 symsize
= elfcpp::Elf_sizes
<32>::sym_size
;
2746 else if (size
== 64)
2748 symsize
= elfcpp::Elf_sizes
<64>::sym_size
;
2754 // Create the dynamic symbol table section.
2756 Output_section
* dynsym
= this->choose_output_section(NULL
, ".dynsym",
2761 Output_section_data
* odata
= new Output_data_fixed_space(index
* symsize
,
2764 dynsym
->add_output_section_data(odata
);
2766 dynsym
->set_info(local_symcount
);
2767 dynsym
->set_entsize(symsize
);
2768 dynsym
->set_addralign(align
);
2770 this->dynsym_section_
= dynsym
;
2772 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
2773 odyn
->add_section_address(elfcpp::DT_SYMTAB
, dynsym
);
2774 odyn
->add_constant(elfcpp::DT_SYMENT
, symsize
);
2776 // If there are more than SHN_LORESERVE allocated sections, we
2777 // create a .dynsym_shndx section. It is possible that we don't
2778 // need one, because it is possible that there are no dynamic
2779 // symbols in any of the sections with indexes larger than
2780 // SHN_LORESERVE. This is probably unusual, though, and at this
2781 // time we don't know the actual section indexes so it is
2782 // inconvenient to check.
2783 if (this->allocated_output_section_count() >= elfcpp::SHN_LORESERVE
)
2785 Output_section
* dynsym_xindex
=
2786 this->choose_output_section(NULL
, ".dynsym_shndx",
2787 elfcpp::SHT_SYMTAB_SHNDX
,
2791 this->dynsym_xindex_
= new Output_symtab_xindex(index
);
2793 dynsym_xindex
->add_output_section_data(this->dynsym_xindex_
);
2795 dynsym_xindex
->set_link_section(dynsym
);
2796 dynsym_xindex
->set_addralign(4);
2797 dynsym_xindex
->set_entsize(4);
2799 dynsym_xindex
->set_after_input_sections();
2801 // This tells the driver code to wait until the symbol table has
2802 // written out before writing out the postprocessing sections,
2803 // including the .dynsym_shndx section.
2804 this->any_postprocessing_sections_
= true;
2807 // Create the dynamic string table section.
2809 Output_section
* dynstr
= this->choose_output_section(NULL
, ".dynstr",
2814 Output_section_data
* strdata
= new Output_data_strtab(&this->dynpool_
);
2815 dynstr
->add_output_section_data(strdata
);
2817 dynsym
->set_link_section(dynstr
);
2818 this->dynamic_section_
->set_link_section(dynstr
);
2820 odyn
->add_section_address(elfcpp::DT_STRTAB
, dynstr
);
2821 odyn
->add_section_size(elfcpp::DT_STRSZ
, dynstr
);
2825 // Create the hash tables.
2827 if (strcmp(parameters
->options().hash_style(), "sysv") == 0
2828 || strcmp(parameters
->options().hash_style(), "both") == 0)
2830 unsigned char* phash
;
2831 unsigned int hashlen
;
2832 Dynobj::create_elf_hash_table(*pdynamic_symbols
, local_symcount
,
2835 Output_section
* hashsec
= this->choose_output_section(NULL
, ".hash",
2840 Output_section_data
* hashdata
= new Output_data_const_buffer(phash
,
2844 hashsec
->add_output_section_data(hashdata
);
2846 hashsec
->set_link_section(dynsym
);
2847 hashsec
->set_entsize(4);
2849 odyn
->add_section_address(elfcpp::DT_HASH
, hashsec
);
2852 if (strcmp(parameters
->options().hash_style(), "gnu") == 0
2853 || strcmp(parameters
->options().hash_style(), "both") == 0)
2855 unsigned char* phash
;
2856 unsigned int hashlen
;
2857 Dynobj::create_gnu_hash_table(*pdynamic_symbols
, local_symcount
,
2860 Output_section
* hashsec
= this->choose_output_section(NULL
, ".gnu.hash",
2861 elfcpp::SHT_GNU_HASH
,
2865 Output_section_data
* hashdata
= new Output_data_const_buffer(phash
,
2869 hashsec
->add_output_section_data(hashdata
);
2871 hashsec
->set_link_section(dynsym
);
2872 hashsec
->set_entsize(4);
2874 odyn
->add_section_address(elfcpp::DT_GNU_HASH
, hashsec
);
2878 // Assign offsets to each local portion of the dynamic symbol table.
2881 Layout::assign_local_dynsym_offsets(const Input_objects
* input_objects
)
2883 Output_section
* dynsym
= this->dynsym_section_
;
2884 gold_assert(dynsym
!= NULL
);
2886 off_t off
= dynsym
->offset();
2888 // Skip the dummy symbol at the start of the section.
2889 off
+= dynsym
->entsize();
2891 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
2892 p
!= input_objects
->relobj_end();
2895 unsigned int count
= (*p
)->set_local_dynsym_offset(off
);
2896 off
+= count
* dynsym
->entsize();
2900 // Create the version sections.
2903 Layout::create_version_sections(const Versions
* versions
,
2904 const Symbol_table
* symtab
,
2905 unsigned int local_symcount
,
2906 const std::vector
<Symbol
*>& dynamic_symbols
,
2907 const Output_section
* dynstr
)
2909 if (!versions
->any_defs() && !versions
->any_needs())
2912 switch (parameters
->size_and_endianness())
2914 #ifdef HAVE_TARGET_32_LITTLE
2915 case Parameters::TARGET_32_LITTLE
:
2916 this->sized_create_version_sections
<32, false>(versions
, symtab
,
2918 dynamic_symbols
, dynstr
);
2921 #ifdef HAVE_TARGET_32_BIG
2922 case Parameters::TARGET_32_BIG
:
2923 this->sized_create_version_sections
<32, true>(versions
, symtab
,
2925 dynamic_symbols
, dynstr
);
2928 #ifdef HAVE_TARGET_64_LITTLE
2929 case Parameters::TARGET_64_LITTLE
:
2930 this->sized_create_version_sections
<64, false>(versions
, symtab
,
2932 dynamic_symbols
, dynstr
);
2935 #ifdef HAVE_TARGET_64_BIG
2936 case Parameters::TARGET_64_BIG
:
2937 this->sized_create_version_sections
<64, true>(versions
, symtab
,
2939 dynamic_symbols
, dynstr
);
2947 // Create the version sections, sized version.
2949 template<int size
, bool big_endian
>
2951 Layout::sized_create_version_sections(
2952 const Versions
* versions
,
2953 const Symbol_table
* symtab
,
2954 unsigned int local_symcount
,
2955 const std::vector
<Symbol
*>& dynamic_symbols
,
2956 const Output_section
* dynstr
)
2958 Output_section
* vsec
= this->choose_output_section(NULL
, ".gnu.version",
2959 elfcpp::SHT_GNU_versym
,
2963 unsigned char* vbuf
;
2965 versions
->symbol_section_contents
<size
, big_endian
>(symtab
, &this->dynpool_
,
2970 Output_section_data
* vdata
= new Output_data_const_buffer(vbuf
, vsize
, 2,
2973 vsec
->add_output_section_data(vdata
);
2974 vsec
->set_entsize(2);
2975 vsec
->set_link_section(this->dynsym_section_
);
2977 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
2978 odyn
->add_section_address(elfcpp::DT_VERSYM
, vsec
);
2980 if (versions
->any_defs())
2982 Output_section
* vdsec
;
2983 vdsec
= this->choose_output_section(NULL
, ".gnu.version_d",
2984 elfcpp::SHT_GNU_verdef
,
2988 unsigned char* vdbuf
;
2989 unsigned int vdsize
;
2990 unsigned int vdentries
;
2991 versions
->def_section_contents
<size
, big_endian
>(&this->dynpool_
, &vdbuf
,
2992 &vdsize
, &vdentries
);
2994 Output_section_data
* vddata
=
2995 new Output_data_const_buffer(vdbuf
, vdsize
, 4, "** version defs");
2997 vdsec
->add_output_section_data(vddata
);
2998 vdsec
->set_link_section(dynstr
);
2999 vdsec
->set_info(vdentries
);
3001 odyn
->add_section_address(elfcpp::DT_VERDEF
, vdsec
);
3002 odyn
->add_constant(elfcpp::DT_VERDEFNUM
, vdentries
);
3005 if (versions
->any_needs())
3007 Output_section
* vnsec
;
3008 vnsec
= this->choose_output_section(NULL
, ".gnu.version_r",
3009 elfcpp::SHT_GNU_verneed
,
3013 unsigned char* vnbuf
;
3014 unsigned int vnsize
;
3015 unsigned int vnentries
;
3016 versions
->need_section_contents
<size
, big_endian
>(&this->dynpool_
,
3020 Output_section_data
* vndata
=
3021 new Output_data_const_buffer(vnbuf
, vnsize
, 4, "** version refs");
3023 vnsec
->add_output_section_data(vndata
);
3024 vnsec
->set_link_section(dynstr
);
3025 vnsec
->set_info(vnentries
);
3027 odyn
->add_section_address(elfcpp::DT_VERNEED
, vnsec
);
3028 odyn
->add_constant(elfcpp::DT_VERNEEDNUM
, vnentries
);
3032 // Create the .interp section and PT_INTERP segment.
3035 Layout::create_interp(const Target
* target
)
3037 const char* interp
= parameters
->options().dynamic_linker();
3040 interp
= target
->dynamic_linker();
3041 gold_assert(interp
!= NULL
);
3044 size_t len
= strlen(interp
) + 1;
3046 Output_section_data
* odata
= new Output_data_const(interp
, len
, 1);
3048 Output_section
* osec
= this->choose_output_section(NULL
, ".interp",
3049 elfcpp::SHT_PROGBITS
,
3052 osec
->add_output_section_data(odata
);
3054 if (!this->script_options_
->saw_phdrs_clause())
3056 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_INTERP
,
3058 oseg
->add_output_section(osec
, elfcpp::PF_R
);
3062 // Finish the .dynamic section and PT_DYNAMIC segment.
3065 Layout::finish_dynamic_section(const Input_objects
* input_objects
,
3066 const Symbol_table
* symtab
)
3068 if (!this->script_options_
->saw_phdrs_clause())
3070 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_DYNAMIC
,
3073 oseg
->add_output_section(this->dynamic_section_
,
3074 elfcpp::PF_R
| elfcpp::PF_W
);
3077 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
3079 for (Input_objects::Dynobj_iterator p
= input_objects
->dynobj_begin();
3080 p
!= input_objects
->dynobj_end();
3083 // FIXME: Handle --as-needed.
3084 odyn
->add_string(elfcpp::DT_NEEDED
, (*p
)->soname());
3087 if (parameters
->options().shared())
3089 const char* soname
= parameters
->options().soname();
3091 odyn
->add_string(elfcpp::DT_SONAME
, soname
);
3094 // FIXME: Support --init and --fini.
3095 Symbol
* sym
= symtab
->lookup("_init");
3096 if (sym
!= NULL
&& sym
->is_defined() && !sym
->is_from_dynobj())
3097 odyn
->add_symbol(elfcpp::DT_INIT
, sym
);
3099 sym
= symtab
->lookup("_fini");
3100 if (sym
!= NULL
&& sym
->is_defined() && !sym
->is_from_dynobj())
3101 odyn
->add_symbol(elfcpp::DT_FINI
, sym
);
3103 // FIXME: Support DT_INIT_ARRAY and DT_FINI_ARRAY.
3105 // Add a DT_RPATH entry if needed.
3106 const General_options::Dir_list
& rpath(parameters
->options().rpath());
3109 std::string rpath_val
;
3110 for (General_options::Dir_list::const_iterator p
= rpath
.begin();
3114 if (rpath_val
.empty())
3115 rpath_val
= p
->name();
3118 // Eliminate duplicates.
3119 General_options::Dir_list::const_iterator q
;
3120 for (q
= rpath
.begin(); q
!= p
; ++q
)
3121 if (q
->name() == p
->name())
3126 rpath_val
+= p
->name();
3131 odyn
->add_string(elfcpp::DT_RPATH
, rpath_val
);
3132 if (parameters
->options().enable_new_dtags())
3133 odyn
->add_string(elfcpp::DT_RUNPATH
, rpath_val
);
3136 // Look for text segments that have dynamic relocations.
3137 bool have_textrel
= false;
3138 if (!this->script_options_
->saw_sections_clause())
3140 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
3141 p
!= this->segment_list_
.end();
3144 if (((*p
)->flags() & elfcpp::PF_W
) == 0
3145 && (*p
)->dynamic_reloc_count() > 0)
3147 have_textrel
= true;
3154 // We don't know the section -> segment mapping, so we are
3155 // conservative and just look for readonly sections with
3156 // relocations. If those sections wind up in writable segments,
3157 // then we have created an unnecessary DT_TEXTREL entry.
3158 for (Section_list::const_iterator p
= this->section_list_
.begin();
3159 p
!= this->section_list_
.end();
3162 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0
3163 && ((*p
)->flags() & elfcpp::SHF_WRITE
) == 0
3164 && ((*p
)->dynamic_reloc_count() > 0))
3166 have_textrel
= true;
3172 // Add a DT_FLAGS entry. We add it even if no flags are set so that
3173 // post-link tools can easily modify these flags if desired.
3174 unsigned int flags
= 0;
3177 // Add a DT_TEXTREL for compatibility with older loaders.
3178 odyn
->add_constant(elfcpp::DT_TEXTREL
, 0);
3179 flags
|= elfcpp::DF_TEXTREL
;
3181 if (parameters
->options().shared() && this->has_static_tls())
3182 flags
|= elfcpp::DF_STATIC_TLS
;
3183 if (parameters
->options().origin())
3184 flags
|= elfcpp::DF_ORIGIN
;
3185 if (parameters
->options().now())
3186 flags
|= elfcpp::DF_BIND_NOW
;
3187 odyn
->add_constant(elfcpp::DT_FLAGS
, flags
);
3190 if (parameters
->options().initfirst())
3191 flags
|= elfcpp::DF_1_INITFIRST
;
3192 if (parameters
->options().interpose())
3193 flags
|= elfcpp::DF_1_INTERPOSE
;
3194 if (parameters
->options().loadfltr())
3195 flags
|= elfcpp::DF_1_LOADFLTR
;
3196 if (parameters
->options().nodefaultlib())
3197 flags
|= elfcpp::DF_1_NODEFLIB
;
3198 if (parameters
->options().nodelete())
3199 flags
|= elfcpp::DF_1_NODELETE
;
3200 if (parameters
->options().nodlopen())
3201 flags
|= elfcpp::DF_1_NOOPEN
;
3202 if (parameters
->options().nodump())
3203 flags
|= elfcpp::DF_1_NODUMP
;
3204 if (!parameters
->options().shared())
3205 flags
&= ~(elfcpp::DF_1_INITFIRST
3206 | elfcpp::DF_1_NODELETE
3207 | elfcpp::DF_1_NOOPEN
);
3208 if (parameters
->options().origin())
3209 flags
|= elfcpp::DF_1_ORIGIN
;
3210 if (parameters
->options().now())
3211 flags
|= elfcpp::DF_1_NOW
;
3213 odyn
->add_constant(elfcpp::DT_FLAGS_1
, flags
);
3216 // The mapping of input section name prefixes to output section names.
3217 // In some cases one prefix is itself a prefix of another prefix; in
3218 // such a case the longer prefix must come first. These prefixes are
3219 // based on the GNU linker default ELF linker script.
3221 #define MAPPING_INIT(f, t) { f, sizeof(f) - 1, t, sizeof(t) - 1 }
3222 const Layout::Section_name_mapping
Layout::section_name_mapping
[] =
3224 MAPPING_INIT(".text.", ".text"),
3225 MAPPING_INIT(".ctors.", ".ctors"),
3226 MAPPING_INIT(".dtors.", ".dtors"),
3227 MAPPING_INIT(".rodata.", ".rodata"),
3228 MAPPING_INIT(".data.rel.ro.local", ".data.rel.ro.local"),
3229 MAPPING_INIT(".data.rel.ro", ".data.rel.ro"),
3230 MAPPING_INIT(".data.", ".data"),
3231 MAPPING_INIT(".bss.", ".bss"),
3232 MAPPING_INIT(".tdata.", ".tdata"),
3233 MAPPING_INIT(".tbss.", ".tbss"),
3234 MAPPING_INIT(".init_array.", ".init_array"),
3235 MAPPING_INIT(".fini_array.", ".fini_array"),
3236 MAPPING_INIT(".sdata.", ".sdata"),
3237 MAPPING_INIT(".sbss.", ".sbss"),
3238 // FIXME: In the GNU linker, .sbss2 and .sdata2 are handled
3239 // differently depending on whether it is creating a shared library.
3240 MAPPING_INIT(".sdata2.", ".sdata"),
3241 MAPPING_INIT(".sbss2.", ".sbss"),
3242 MAPPING_INIT(".lrodata.", ".lrodata"),
3243 MAPPING_INIT(".ldata.", ".ldata"),
3244 MAPPING_INIT(".lbss.", ".lbss"),
3245 MAPPING_INIT(".gcc_except_table.", ".gcc_except_table"),
3246 MAPPING_INIT(".gnu.linkonce.d.rel.ro.local.", ".data.rel.ro.local"),
3247 MAPPING_INIT(".gnu.linkonce.d.rel.ro.", ".data.rel.ro"),
3248 MAPPING_INIT(".gnu.linkonce.t.", ".text"),
3249 MAPPING_INIT(".gnu.linkonce.r.", ".rodata"),
3250 MAPPING_INIT(".gnu.linkonce.d.", ".data"),
3251 MAPPING_INIT(".gnu.linkonce.b.", ".bss"),
3252 MAPPING_INIT(".gnu.linkonce.s.", ".sdata"),
3253 MAPPING_INIT(".gnu.linkonce.sb.", ".sbss"),
3254 MAPPING_INIT(".gnu.linkonce.s2.", ".sdata"),
3255 MAPPING_INIT(".gnu.linkonce.sb2.", ".sbss"),
3256 MAPPING_INIT(".gnu.linkonce.wi.", ".debug_info"),
3257 MAPPING_INIT(".gnu.linkonce.td.", ".tdata"),
3258 MAPPING_INIT(".gnu.linkonce.tb.", ".tbss"),
3259 MAPPING_INIT(".gnu.linkonce.lr.", ".lrodata"),
3260 MAPPING_INIT(".gnu.linkonce.l.", ".ldata"),
3261 MAPPING_INIT(".gnu.linkonce.lb.", ".lbss"),
3262 MAPPING_INIT(".ARM.extab.", ".ARM.extab"),
3263 MAPPING_INIT(".gnu.linkonce.armextab.", ".ARM.extab"),
3264 MAPPING_INIT(".ARM.exidx.", ".ARM.exidx"),
3265 MAPPING_INIT(".gnu.linkonce.armexidx.", ".ARM.exidx"),
3269 const int Layout::section_name_mapping_count
=
3270 (sizeof(Layout::section_name_mapping
)
3271 / sizeof(Layout::section_name_mapping
[0]));
3273 // Choose the output section name to use given an input section name.
3274 // Set *PLEN to the length of the name. *PLEN is initialized to the
3278 Layout::output_section_name(const char* name
, size_t* plen
)
3280 // gcc 4.3 generates the following sorts of section names when it
3281 // needs a section name specific to a function:
3287 // .data.rel.local.FN
3289 // .data.rel.ro.local.FN
3296 // The GNU linker maps all of those to the part before the .FN,
3297 // except that .data.rel.local.FN is mapped to .data, and
3298 // .data.rel.ro.local.FN is mapped to .data.rel.ro. The sections
3299 // beginning with .data.rel.ro.local are grouped together.
3301 // For an anonymous namespace, the string FN can contain a '.'.
3303 // Also of interest: .rodata.strN.N, .rodata.cstN, both of which the
3304 // GNU linker maps to .rodata.
3306 // The .data.rel.ro sections are used with -z relro. The sections
3307 // are recognized by name. We use the same names that the GNU
3308 // linker does for these sections.
3310 // It is hard to handle this in a principled way, so we don't even
3311 // try. We use a table of mappings. If the input section name is
3312 // not found in the table, we simply use it as the output section
3315 const Section_name_mapping
* psnm
= section_name_mapping
;
3316 for (int i
= 0; i
< section_name_mapping_count
; ++i
, ++psnm
)
3318 if (strncmp(name
, psnm
->from
, psnm
->fromlen
) == 0)
3320 *plen
= psnm
->tolen
;
3328 // Check if a comdat group or .gnu.linkonce section with the given
3329 // NAME is selected for the link. If there is already a section,
3330 // *KEPT_SECTION is set to point to the existing section and the
3331 // function returns false. Otherwise, OBJECT, SHNDX, IS_COMDAT, and
3332 // IS_GROUP_NAME are recorded for this NAME in the layout object,
3333 // *KEPT_SECTION is set to the internal copy and the function returns
3337 Layout::find_or_add_kept_section(const std::string
& name
,
3342 Kept_section
** kept_section
)
3344 // It's normal to see a couple of entries here, for the x86 thunk
3345 // sections. If we see more than a few, we're linking a C++
3346 // program, and we resize to get more space to minimize rehashing.
3347 if (this->signatures_
.size() > 4
3348 && !this->resized_signatures_
)
3350 reserve_unordered_map(&this->signatures_
,
3351 this->number_of_input_files_
* 64);
3352 this->resized_signatures_
= true;
3355 Kept_section candidate
;
3356 std::pair
<Signatures::iterator
, bool> ins
=
3357 this->signatures_
.insert(std::make_pair(name
, candidate
));
3359 if (kept_section
!= NULL
)
3360 *kept_section
= &ins
.first
->second
;
3363 // This is the first time we've seen this signature.
3364 ins
.first
->second
.set_object(object
);
3365 ins
.first
->second
.set_shndx(shndx
);
3367 ins
.first
->second
.set_is_comdat();
3369 ins
.first
->second
.set_is_group_name();
3373 // We have already seen this signature.
3375 if (ins
.first
->second
.is_group_name())
3377 // We've already seen a real section group with this signature.
3378 // If the kept group is from a plugin object, and we're in the
3379 // replacement phase, accept the new one as a replacement.
3380 if (ins
.first
->second
.object() == NULL
3381 && parameters
->options().plugins()->in_replacement_phase())
3383 ins
.first
->second
.set_object(object
);
3384 ins
.first
->second
.set_shndx(shndx
);
3389 else if (is_group_name
)
3391 // This is a real section group, and we've already seen a
3392 // linkonce section with this signature. Record that we've seen
3393 // a section group, and don't include this section group.
3394 ins
.first
->second
.set_is_group_name();
3399 // We've already seen a linkonce section and this is a linkonce
3400 // section. These don't block each other--this may be the same
3401 // symbol name with different section types.
3406 // Store the allocated sections into the section list.
3409 Layout::get_allocated_sections(Section_list
* section_list
) const
3411 for (Section_list::const_iterator p
= this->section_list_
.begin();
3412 p
!= this->section_list_
.end();
3414 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0)
3415 section_list
->push_back(*p
);
3418 // Create an output segment.
3421 Layout::make_output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
3423 gold_assert(!parameters
->options().relocatable());
3424 Output_segment
* oseg
= new Output_segment(type
, flags
);
3425 this->segment_list_
.push_back(oseg
);
3427 if (type
== elfcpp::PT_TLS
)
3428 this->tls_segment_
= oseg
;
3429 else if (type
== elfcpp::PT_GNU_RELRO
)
3430 this->relro_segment_
= oseg
;
3435 // Write out the Output_sections. Most won't have anything to write,
3436 // since most of the data will come from input sections which are
3437 // handled elsewhere. But some Output_sections do have Output_data.
3440 Layout::write_output_sections(Output_file
* of
) const
3442 for (Section_list::const_iterator p
= this->section_list_
.begin();
3443 p
!= this->section_list_
.end();
3446 if (!(*p
)->after_input_sections())
3451 // Write out data not associated with a section or the symbol table.
3454 Layout::write_data(const Symbol_table
* symtab
, Output_file
* of
) const
3456 if (!parameters
->options().strip_all())
3458 const Output_section
* symtab_section
= this->symtab_section_
;
3459 for (Section_list::const_iterator p
= this->section_list_
.begin();
3460 p
!= this->section_list_
.end();
3463 if ((*p
)->needs_symtab_index())
3465 gold_assert(symtab_section
!= NULL
);
3466 unsigned int index
= (*p
)->symtab_index();
3467 gold_assert(index
> 0 && index
!= -1U);
3468 off_t off
= (symtab_section
->offset()
3469 + index
* symtab_section
->entsize());
3470 symtab
->write_section_symbol(*p
, this->symtab_xindex_
, of
, off
);
3475 const Output_section
* dynsym_section
= this->dynsym_section_
;
3476 for (Section_list::const_iterator p
= this->section_list_
.begin();
3477 p
!= this->section_list_
.end();
3480 if ((*p
)->needs_dynsym_index())
3482 gold_assert(dynsym_section
!= NULL
);
3483 unsigned int index
= (*p
)->dynsym_index();
3484 gold_assert(index
> 0 && index
!= -1U);
3485 off_t off
= (dynsym_section
->offset()
3486 + index
* dynsym_section
->entsize());
3487 symtab
->write_section_symbol(*p
, this->dynsym_xindex_
, of
, off
);
3491 // Write out the Output_data which are not in an Output_section.
3492 for (Data_list::const_iterator p
= this->special_output_list_
.begin();
3493 p
!= this->special_output_list_
.end();
3498 // Write out the Output_sections which can only be written after the
3499 // input sections are complete.
3502 Layout::write_sections_after_input_sections(Output_file
* of
)
3504 // Determine the final section offsets, and thus the final output
3505 // file size. Note we finalize the .shstrab last, to allow the
3506 // after_input_section sections to modify their section-names before
3508 if (this->any_postprocessing_sections_
)
3510 off_t off
= this->output_file_size_
;
3511 off
= this->set_section_offsets(off
, POSTPROCESSING_SECTIONS_PASS
);
3513 // Now that we've finalized the names, we can finalize the shstrab.
3515 this->set_section_offsets(off
,
3516 STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
);
3518 if (off
> this->output_file_size_
)
3521 this->output_file_size_
= off
;
3525 for (Section_list::const_iterator p
= this->section_list_
.begin();
3526 p
!= this->section_list_
.end();
3529 if ((*p
)->after_input_sections())
3533 this->section_headers_
->write(of
);
3536 // If the build ID requires computing a checksum, do so here, and
3537 // write it out. We compute a checksum over the entire file because
3538 // that is simplest.
3541 Layout::write_build_id(Output_file
* of
) const
3543 if (this->build_id_note_
== NULL
)
3546 const unsigned char* iv
= of
->get_input_view(0, this->output_file_size_
);
3548 unsigned char* ov
= of
->get_output_view(this->build_id_note_
->offset(),
3549 this->build_id_note_
->data_size());
3551 const char* style
= parameters
->options().build_id();
3552 if (strcmp(style
, "sha1") == 0)
3555 sha1_init_ctx(&ctx
);
3556 sha1_process_bytes(iv
, this->output_file_size_
, &ctx
);
3557 sha1_finish_ctx(&ctx
, ov
);
3559 else if (strcmp(style
, "md5") == 0)
3563 md5_process_bytes(iv
, this->output_file_size_
, &ctx
);
3564 md5_finish_ctx(&ctx
, ov
);
3569 of
->write_output_view(this->build_id_note_
->offset(),
3570 this->build_id_note_
->data_size(),
3573 of
->free_input_view(0, this->output_file_size_
, iv
);
3576 // Write out a binary file. This is called after the link is
3577 // complete. IN is the temporary output file we used to generate the
3578 // ELF code. We simply walk through the segments, read them from
3579 // their file offset in IN, and write them to their load address in
3580 // the output file. FIXME: with a bit more work, we could support
3581 // S-records and/or Intel hex format here.
3584 Layout::write_binary(Output_file
* in
) const
3586 gold_assert(parameters
->options().oformat_enum()
3587 == General_options::OBJECT_FORMAT_BINARY
);
3589 // Get the size of the binary file.
3590 uint64_t max_load_address
= 0;
3591 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
3592 p
!= this->segment_list_
.end();
3595 if ((*p
)->type() == elfcpp::PT_LOAD
&& (*p
)->filesz() > 0)
3597 uint64_t max_paddr
= (*p
)->paddr() + (*p
)->filesz();
3598 if (max_paddr
> max_load_address
)
3599 max_load_address
= max_paddr
;
3603 Output_file
out(parameters
->options().output_file_name());
3604 out
.open(max_load_address
);
3606 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
3607 p
!= this->segment_list_
.end();
3610 if ((*p
)->type() == elfcpp::PT_LOAD
&& (*p
)->filesz() > 0)
3612 const unsigned char* vin
= in
->get_input_view((*p
)->offset(),
3614 unsigned char* vout
= out
.get_output_view((*p
)->paddr(),
3616 memcpy(vout
, vin
, (*p
)->filesz());
3617 out
.write_output_view((*p
)->paddr(), (*p
)->filesz(), vout
);
3618 in
->free_input_view((*p
)->offset(), (*p
)->filesz(), vin
);
3625 // Print the output sections to the map file.
3628 Layout::print_to_mapfile(Mapfile
* mapfile
) const
3630 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
3631 p
!= this->segment_list_
.end();
3633 (*p
)->print_sections_to_mapfile(mapfile
);
3636 // Print statistical information to stderr. This is used for --stats.
3639 Layout::print_stats() const
3641 this->namepool_
.print_stats("section name pool");
3642 this->sympool_
.print_stats("output symbol name pool");
3643 this->dynpool_
.print_stats("dynamic name pool");
3645 for (Section_list::const_iterator p
= this->section_list_
.begin();
3646 p
!= this->section_list_
.end();
3648 (*p
)->print_merge_stats();
3651 // Write_sections_task methods.
3653 // We can always run this task.
3656 Write_sections_task::is_runnable()
3661 // We need to unlock both OUTPUT_SECTIONS_BLOCKER and FINAL_BLOCKER
3665 Write_sections_task::locks(Task_locker
* tl
)
3667 tl
->add(this, this->output_sections_blocker_
);
3668 tl
->add(this, this->final_blocker_
);
3671 // Run the task--write out the data.
3674 Write_sections_task::run(Workqueue
*)
3676 this->layout_
->write_output_sections(this->of_
);
3679 // Write_data_task methods.
3681 // We can always run this task.
3684 Write_data_task::is_runnable()
3689 // We need to unlock FINAL_BLOCKER when finished.
3692 Write_data_task::locks(Task_locker
* tl
)
3694 tl
->add(this, this->final_blocker_
);
3697 // Run the task--write out the data.
3700 Write_data_task::run(Workqueue
*)
3702 this->layout_
->write_data(this->symtab_
, this->of_
);
3705 // Write_symbols_task methods.
3707 // We can always run this task.
3710 Write_symbols_task::is_runnable()
3715 // We need to unlock FINAL_BLOCKER when finished.
3718 Write_symbols_task::locks(Task_locker
* tl
)
3720 tl
->add(this, this->final_blocker_
);
3723 // Run the task--write out the symbols.
3726 Write_symbols_task::run(Workqueue
*)
3728 this->symtab_
->write_globals(this->sympool_
, this->dynpool_
,
3729 this->layout_
->symtab_xindex(),
3730 this->layout_
->dynsym_xindex(), this->of_
);
3733 // Write_after_input_sections_task methods.
3735 // We can only run this task after the input sections have completed.
3738 Write_after_input_sections_task::is_runnable()
3740 if (this->input_sections_blocker_
->is_blocked())
3741 return this->input_sections_blocker_
;
3745 // We need to unlock FINAL_BLOCKER when finished.
3748 Write_after_input_sections_task::locks(Task_locker
* tl
)
3750 tl
->add(this, this->final_blocker_
);
3756 Write_after_input_sections_task::run(Workqueue
*)
3758 this->layout_
->write_sections_after_input_sections(this->of_
);
3761 // Close_task_runner methods.
3763 // Run the task--close the file.
3766 Close_task_runner::run(Workqueue
*, const Task
*)
3768 // If we need to compute a checksum for the BUILD if, we do so here.
3769 this->layout_
->write_build_id(this->of_
);
3771 // If we've been asked to create a binary file, we do so here.
3772 if (this->options_
->oformat_enum() != General_options::OBJECT_FORMAT_ELF
)
3773 this->layout_
->write_binary(this->of_
);
3778 // Instantiate the templates we need. We could use the configure
3779 // script to restrict this to only the ones for implemented targets.
3781 #ifdef HAVE_TARGET_32_LITTLE
3784 Layout::layout
<32, false>(Sized_relobj
<32, false>* object
, unsigned int shndx
,
3786 const elfcpp::Shdr
<32, false>& shdr
,
3787 unsigned int, unsigned int, off_t
*);
3790 #ifdef HAVE_TARGET_32_BIG
3793 Layout::layout
<32, true>(Sized_relobj
<32, true>* object
, unsigned int shndx
,
3795 const elfcpp::Shdr
<32, true>& shdr
,
3796 unsigned int, unsigned int, off_t
*);
3799 #ifdef HAVE_TARGET_64_LITTLE
3802 Layout::layout
<64, false>(Sized_relobj
<64, false>* object
, unsigned int shndx
,
3804 const elfcpp::Shdr
<64, false>& shdr
,
3805 unsigned int, unsigned int, off_t
*);
3808 #ifdef HAVE_TARGET_64_BIG
3811 Layout::layout
<64, true>(Sized_relobj
<64, true>* object
, unsigned int shndx
,
3813 const elfcpp::Shdr
<64, true>& shdr
,
3814 unsigned int, unsigned int, off_t
*);
3817 #ifdef HAVE_TARGET_32_LITTLE
3820 Layout::layout_reloc
<32, false>(Sized_relobj
<32, false>* object
,
3821 unsigned int reloc_shndx
,
3822 const elfcpp::Shdr
<32, false>& shdr
,
3823 Output_section
* data_section
,
3824 Relocatable_relocs
* rr
);
3827 #ifdef HAVE_TARGET_32_BIG
3830 Layout::layout_reloc
<32, true>(Sized_relobj
<32, true>* object
,
3831 unsigned int reloc_shndx
,
3832 const elfcpp::Shdr
<32, true>& shdr
,
3833 Output_section
* data_section
,
3834 Relocatable_relocs
* rr
);
3837 #ifdef HAVE_TARGET_64_LITTLE
3840 Layout::layout_reloc
<64, false>(Sized_relobj
<64, false>* object
,
3841 unsigned int reloc_shndx
,
3842 const elfcpp::Shdr
<64, false>& shdr
,
3843 Output_section
* data_section
,
3844 Relocatable_relocs
* rr
);
3847 #ifdef HAVE_TARGET_64_BIG
3850 Layout::layout_reloc
<64, true>(Sized_relobj
<64, true>* object
,
3851 unsigned int reloc_shndx
,
3852 const elfcpp::Shdr
<64, true>& shdr
,
3853 Output_section
* data_section
,
3854 Relocatable_relocs
* rr
);
3857 #ifdef HAVE_TARGET_32_LITTLE
3860 Layout::layout_group
<32, false>(Symbol_table
* symtab
,
3861 Sized_relobj
<32, false>* object
,
3863 const char* group_section_name
,
3864 const char* signature
,
3865 const elfcpp::Shdr
<32, false>& shdr
,
3866 elfcpp::Elf_Word flags
,
3867 std::vector
<unsigned int>* shndxes
);
3870 #ifdef HAVE_TARGET_32_BIG
3873 Layout::layout_group
<32, true>(Symbol_table
* symtab
,
3874 Sized_relobj
<32, true>* object
,
3876 const char* group_section_name
,
3877 const char* signature
,
3878 const elfcpp::Shdr
<32, true>& shdr
,
3879 elfcpp::Elf_Word flags
,
3880 std::vector
<unsigned int>* shndxes
);
3883 #ifdef HAVE_TARGET_64_LITTLE
3886 Layout::layout_group
<64, false>(Symbol_table
* symtab
,
3887 Sized_relobj
<64, false>* object
,
3889 const char* group_section_name
,
3890 const char* signature
,
3891 const elfcpp::Shdr
<64, false>& shdr
,
3892 elfcpp::Elf_Word flags
,
3893 std::vector
<unsigned int>* shndxes
);
3896 #ifdef HAVE_TARGET_64_BIG
3899 Layout::layout_group
<64, true>(Symbol_table
* symtab
,
3900 Sized_relobj
<64, true>* object
,
3902 const char* group_section_name
,
3903 const char* signature
,
3904 const elfcpp::Shdr
<64, true>& shdr
,
3905 elfcpp::Elf_Word flags
,
3906 std::vector
<unsigned int>* shndxes
);
3909 #ifdef HAVE_TARGET_32_LITTLE
3912 Layout::layout_eh_frame
<32, false>(Sized_relobj
<32, false>* object
,
3913 const unsigned char* symbols
,
3915 const unsigned char* symbol_names
,
3916 off_t symbol_names_size
,
3918 const elfcpp::Shdr
<32, false>& shdr
,
3919 unsigned int reloc_shndx
,
3920 unsigned int reloc_type
,
3924 #ifdef HAVE_TARGET_32_BIG
3927 Layout::layout_eh_frame
<32, true>(Sized_relobj
<32, true>* object
,
3928 const unsigned char* symbols
,
3930 const unsigned char* symbol_names
,
3931 off_t symbol_names_size
,
3933 const elfcpp::Shdr
<32, true>& shdr
,
3934 unsigned int reloc_shndx
,
3935 unsigned int reloc_type
,
3939 #ifdef HAVE_TARGET_64_LITTLE
3942 Layout::layout_eh_frame
<64, false>(Sized_relobj
<64, false>* object
,
3943 const unsigned char* symbols
,
3945 const unsigned char* symbol_names
,
3946 off_t symbol_names_size
,
3948 const elfcpp::Shdr
<64, false>& shdr
,
3949 unsigned int reloc_shndx
,
3950 unsigned int reloc_type
,
3954 #ifdef HAVE_TARGET_64_BIG
3957 Layout::layout_eh_frame
<64, true>(Sized_relobj
<64, true>* object
,
3958 const unsigned char* symbols
,
3960 const unsigned char* symbol_names
,
3961 off_t symbol_names_size
,
3963 const elfcpp::Shdr
<64, true>& shdr
,
3964 unsigned int reloc_shndx
,
3965 unsigned int reloc_type
,
3969 } // End namespace gold.