1 // layout.cc -- lay out output file sections for gold
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011, 2012
4 // Free Software Foundation, Inc.
5 // Written by Ian Lance Taylor <iant@google.com>.
7 // This file is part of gold.
9 // This program is free software; you can redistribute it and/or modify
10 // it under the terms of the GNU General Public License as published by
11 // the Free Software Foundation; either version 3 of the License, or
12 // (at your option) any later version.
14 // This program is distributed in the hope that it will be useful,
15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 // GNU General Public License for more details.
19 // You should have received a copy of the GNU General Public License
20 // along with this program; if not, write to the Free Software
21 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
22 // MA 02110-1301, USA.
35 #include "libiberty.h"
39 #include "parameters.h"
43 #include "script-sections.h"
48 #include "gdb-index.h"
49 #include "compressed_output.h"
50 #include "reduced_debug_output.h"
53 #include "descriptors.h"
55 #include "incremental.h"
63 // The total number of free lists used.
64 unsigned int Free_list::num_lists
= 0;
65 // The total number of free list nodes used.
66 unsigned int Free_list::num_nodes
= 0;
67 // The total number of calls to Free_list::remove.
68 unsigned int Free_list::num_removes
= 0;
69 // The total number of nodes visited during calls to Free_list::remove.
70 unsigned int Free_list::num_remove_visits
= 0;
71 // The total number of calls to Free_list::allocate.
72 unsigned int Free_list::num_allocates
= 0;
73 // The total number of nodes visited during calls to Free_list::allocate.
74 unsigned int Free_list::num_allocate_visits
= 0;
76 // Initialize the free list. Creates a single free list node that
77 // describes the entire region of length LEN. If EXTEND is true,
78 // allocate() is allowed to extend the region beyond its initial
82 Free_list::init(off_t len
, bool extend
)
84 this->list_
.push_front(Free_list_node(0, len
));
85 this->last_remove_
= this->list_
.begin();
86 this->extend_
= extend
;
88 ++Free_list::num_lists
;
89 ++Free_list::num_nodes
;
92 // Remove a chunk from the free list. Because we start with a single
93 // node that covers the entire section, and remove chunks from it one
94 // at a time, we do not need to coalesce chunks or handle cases that
95 // span more than one free node. We expect to remove chunks from the
96 // free list in order, and we expect to have only a few chunks of free
97 // space left (corresponding to files that have changed since the last
98 // incremental link), so a simple linear list should provide sufficient
102 Free_list::remove(off_t start
, off_t end
)
106 gold_assert(start
< end
);
108 ++Free_list::num_removes
;
110 Iterator p
= this->last_remove_
;
111 if (p
->start_
> start
)
112 p
= this->list_
.begin();
114 for (; p
!= this->list_
.end(); ++p
)
116 ++Free_list::num_remove_visits
;
117 // Find a node that wholly contains the indicated region.
118 if (p
->start_
<= start
&& p
->end_
>= end
)
120 // Case 1: the indicated region spans the whole node.
121 // Add some fuzz to avoid creating tiny free chunks.
122 if (p
->start_
+ 3 >= start
&& p
->end_
<= end
+ 3)
123 p
= this->list_
.erase(p
);
124 // Case 2: remove a chunk from the start of the node.
125 else if (p
->start_
+ 3 >= start
)
127 // Case 3: remove a chunk from the end of the node.
128 else if (p
->end_
<= end
+ 3)
130 // Case 4: remove a chunk from the middle, and split
131 // the node into two.
134 Free_list_node
newnode(p
->start_
, start
);
136 this->list_
.insert(p
, newnode
);
137 ++Free_list::num_nodes
;
139 this->last_remove_
= p
;
144 // Did not find a node containing the given chunk. This could happen
145 // because a small chunk was already removed due to the fuzz.
146 gold_debug(DEBUG_INCREMENTAL
,
147 "Free_list::remove(%d,%d) not found",
148 static_cast<int>(start
), static_cast<int>(end
));
151 // Allocate a chunk of size LEN from the free list. Returns -1ULL
152 // if a sufficiently large chunk of free space is not found.
153 // We use a simple first-fit algorithm.
156 Free_list::allocate(off_t len
, uint64_t align
, off_t minoff
)
158 gold_debug(DEBUG_INCREMENTAL
,
159 "Free_list::allocate(%08lx, %d, %08lx)",
160 static_cast<long>(len
), static_cast<int>(align
),
161 static_cast<long>(minoff
));
163 return align_address(minoff
, align
);
165 ++Free_list::num_allocates
;
167 // We usually want to drop free chunks smaller than 4 bytes.
168 // If we need to guarantee a minimum hole size, though, we need
169 // to keep track of all free chunks.
170 const int fuzz
= this->min_hole_
> 0 ? 0 : 3;
172 for (Iterator p
= this->list_
.begin(); p
!= this->list_
.end(); ++p
)
174 ++Free_list::num_allocate_visits
;
175 off_t start
= p
->start_
> minoff
? p
->start_
: minoff
;
176 start
= align_address(start
, align
);
177 off_t end
= start
+ len
;
178 if (end
> p
->end_
&& p
->end_
== this->length_
&& this->extend_
)
183 if (end
== p
->end_
|| (end
<= p
->end_
- this->min_hole_
))
185 if (p
->start_
+ fuzz
>= start
&& p
->end_
<= end
+ fuzz
)
186 this->list_
.erase(p
);
187 else if (p
->start_
+ fuzz
>= start
)
189 else if (p
->end_
<= end
+ fuzz
)
193 Free_list_node
newnode(p
->start_
, start
);
195 this->list_
.insert(p
, newnode
);
196 ++Free_list::num_nodes
;
203 off_t start
= align_address(this->length_
, align
);
204 this->length_
= start
+ len
;
210 // Dump the free list (for debugging).
214 gold_info("Free list:\n start end length\n");
215 for (Iterator p
= this->list_
.begin(); p
!= this->list_
.end(); ++p
)
216 gold_info(" %08lx %08lx %08lx", static_cast<long>(p
->start_
),
217 static_cast<long>(p
->end_
),
218 static_cast<long>(p
->end_
- p
->start_
));
221 // Print the statistics for the free lists.
223 Free_list::print_stats()
225 fprintf(stderr
, _("%s: total free lists: %u\n"),
226 program_name
, Free_list::num_lists
);
227 fprintf(stderr
, _("%s: total free list nodes: %u\n"),
228 program_name
, Free_list::num_nodes
);
229 fprintf(stderr
, _("%s: calls to Free_list::remove: %u\n"),
230 program_name
, Free_list::num_removes
);
231 fprintf(stderr
, _("%s: nodes visited: %u\n"),
232 program_name
, Free_list::num_remove_visits
);
233 fprintf(stderr
, _("%s: calls to Free_list::allocate: %u\n"),
234 program_name
, Free_list::num_allocates
);
235 fprintf(stderr
, _("%s: nodes visited: %u\n"),
236 program_name
, Free_list::num_allocate_visits
);
239 // Layout::Relaxation_debug_check methods.
241 // Check that sections and special data are in reset states.
242 // We do not save states for Output_sections and special Output_data.
243 // So we check that they have not assigned any addresses or offsets.
244 // clean_up_after_relaxation simply resets their addresses and offsets.
246 Layout::Relaxation_debug_check::check_output_data_for_reset_values(
247 const Layout::Section_list
& sections
,
248 const Layout::Data_list
& special_outputs
)
250 for(Layout::Section_list::const_iterator p
= sections
.begin();
253 gold_assert((*p
)->address_and_file_offset_have_reset_values());
255 for(Layout::Data_list::const_iterator p
= special_outputs
.begin();
256 p
!= special_outputs
.end();
258 gold_assert((*p
)->address_and_file_offset_have_reset_values());
261 // Save information of SECTIONS for checking later.
264 Layout::Relaxation_debug_check::read_sections(
265 const Layout::Section_list
& sections
)
267 for(Layout::Section_list::const_iterator p
= sections
.begin();
271 Output_section
* os
= *p
;
273 info
.output_section
= os
;
274 info
.address
= os
->is_address_valid() ? os
->address() : 0;
275 info
.data_size
= os
->is_data_size_valid() ? os
->data_size() : -1;
276 info
.offset
= os
->is_offset_valid()? os
->offset() : -1 ;
277 this->section_infos_
.push_back(info
);
281 // Verify SECTIONS using previously recorded information.
284 Layout::Relaxation_debug_check::verify_sections(
285 const Layout::Section_list
& sections
)
288 for(Layout::Section_list::const_iterator p
= sections
.begin();
292 Output_section
* os
= *p
;
293 uint64_t address
= os
->is_address_valid() ? os
->address() : 0;
294 off_t data_size
= os
->is_data_size_valid() ? os
->data_size() : -1;
295 off_t offset
= os
->is_offset_valid()? os
->offset() : -1 ;
297 if (i
>= this->section_infos_
.size())
299 gold_fatal("Section_info of %s missing.\n", os
->name());
301 const Section_info
& info
= this->section_infos_
[i
];
302 if (os
!= info
.output_section
)
303 gold_fatal("Section order changed. Expecting %s but see %s\n",
304 info
.output_section
->name(), os
->name());
305 if (address
!= info
.address
306 || data_size
!= info
.data_size
307 || offset
!= info
.offset
)
308 gold_fatal("Section %s changed.\n", os
->name());
312 // Layout_task_runner methods.
314 // Lay out the sections. This is called after all the input objects
318 Layout_task_runner::run(Workqueue
* workqueue
, const Task
* task
)
320 Layout
* layout
= this->layout_
;
321 off_t file_size
= layout
->finalize(this->input_objects_
,
326 // Now we know the final size of the output file and we know where
327 // each piece of information goes.
329 if (this->mapfile_
!= NULL
)
331 this->mapfile_
->print_discarded_sections(this->input_objects_
);
332 layout
->print_to_mapfile(this->mapfile_
);
336 if (layout
->incremental_base() == NULL
)
338 of
= new Output_file(parameters
->options().output_file_name());
339 if (this->options_
.oformat_enum() != General_options::OBJECT_FORMAT_ELF
)
340 of
->set_is_temporary();
345 of
= layout
->incremental_base()->output_file();
347 // Apply the incremental relocations for symbols whose values
348 // have changed. We do this before we resize the file and start
349 // writing anything else to it, so that we can read the old
350 // incremental information from the file before (possibly)
352 if (parameters
->incremental_update())
353 layout
->incremental_base()->apply_incremental_relocs(this->symtab_
,
357 of
->resize(file_size
);
360 // Queue up the final set of tasks.
361 gold::queue_final_tasks(this->options_
, this->input_objects_
,
362 this->symtab_
, layout
, workqueue
, of
);
367 Layout::Layout(int number_of_input_files
, Script_options
* script_options
)
368 : number_of_input_files_(number_of_input_files
),
369 script_options_(script_options
),
377 unattached_section_list_(),
378 special_output_list_(),
379 section_headers_(NULL
),
381 relro_segment_(NULL
),
382 interp_segment_(NULL
),
384 symtab_section_(NULL
),
385 symtab_xindex_(NULL
),
386 dynsym_section_(NULL
),
387 dynsym_xindex_(NULL
),
388 dynamic_section_(NULL
),
389 dynamic_symbol_(NULL
),
391 eh_frame_section_(NULL
),
392 eh_frame_data_(NULL
),
393 added_eh_frame_data_(false),
394 eh_frame_hdr_section_(NULL
),
395 gdb_index_data_(NULL
),
396 build_id_note_(NULL
),
400 output_file_size_(-1),
401 have_added_input_section_(false),
402 sections_are_attached_(false),
403 input_requires_executable_stack_(false),
404 input_with_gnu_stack_note_(false),
405 input_without_gnu_stack_note_(false),
406 has_static_tls_(false),
407 any_postprocessing_sections_(false),
408 resized_signatures_(false),
409 have_stabstr_section_(false),
410 section_ordering_specified_(false),
411 incremental_inputs_(NULL
),
412 record_output_section_data_from_script_(false),
413 script_output_section_data_list_(),
414 segment_states_(NULL
),
415 relaxation_debug_check_(NULL
),
416 section_order_map_(),
417 input_section_position_(),
418 input_section_glob_(),
419 incremental_base_(NULL
),
422 // Make space for more than enough segments for a typical file.
423 // This is just for efficiency--it's OK if we wind up needing more.
424 this->segment_list_
.reserve(12);
426 // We expect two unattached Output_data objects: the file header and
427 // the segment headers.
428 this->special_output_list_
.reserve(2);
430 // Initialize structure needed for an incremental build.
431 if (parameters
->incremental())
432 this->incremental_inputs_
= new Incremental_inputs
;
434 // The section name pool is worth optimizing in all cases, because
435 // it is small, but there are often overlaps due to .rel sections.
436 this->namepool_
.set_optimize();
439 // For incremental links, record the base file to be modified.
442 Layout::set_incremental_base(Incremental_binary
* base
)
444 this->incremental_base_
= base
;
445 this->free_list_
.init(base
->output_file()->filesize(), true);
448 // Hash a key we use to look up an output section mapping.
451 Layout::Hash_key::operator()(const Layout::Key
& k
) const
453 return k
.first
+ k
.second
.first
+ k
.second
.second
;
456 // Returns whether the given section is in the list of
457 // debug-sections-used-by-some-version-of-gdb. Currently,
458 // we've checked versions of gdb up to and including 7.4.
460 static const char* gdb_sections
[] =
462 ".debug_addr", // Fission extension
463 // ".debug_aranges", // not used by gdb as of 7.4
470 // ".debug_pubnames", // not used by gdb as of 7.4
471 // ".debug_pubtypes", // not used by gdb as of 7.4
476 static const char* lines_only_debug_sections
[] =
478 // ".debug_addr", // Fission extension
479 // ".debug_aranges", // not used by gdb as of 7.4
486 // ".debug_pubnames", // not used by gdb as of 7.4
487 // ".debug_pubtypes", // not used by gdb as of 7.4
493 is_gdb_debug_section(const char* str
)
495 // We can do this faster: binary search or a hashtable. But why bother?
496 for (size_t i
= 0; i
< sizeof(gdb_sections
)/sizeof(*gdb_sections
); ++i
)
497 if (strcmp(str
, gdb_sections
[i
]) == 0)
503 is_lines_only_debug_section(const char* str
)
505 // We can do this faster: binary search or a hashtable. But why bother?
507 i
< sizeof(lines_only_debug_sections
)/sizeof(*lines_only_debug_sections
);
509 if (strcmp(str
, lines_only_debug_sections
[i
]) == 0)
514 // Sometimes we compress sections. This is typically done for
515 // sections that are not part of normal program execution (such as
516 // .debug_* sections), and where the readers of these sections know
517 // how to deal with compressed sections. This routine doesn't say for
518 // certain whether we'll compress -- it depends on commandline options
519 // as well -- just whether this section is a candidate for compression.
520 // (The Output_compressed_section class decides whether to compress
521 // a given section, and picks the name of the compressed section.)
524 is_compressible_debug_section(const char* secname
)
526 return (is_prefix_of(".debug", secname
));
529 // We may see compressed debug sections in input files. Return TRUE
530 // if this is the name of a compressed debug section.
533 is_compressed_debug_section(const char* secname
)
535 return (is_prefix_of(".zdebug", secname
));
538 // Whether to include this section in the link.
540 template<int size
, bool big_endian
>
542 Layout::include_section(Sized_relobj_file
<size
, big_endian
>*, const char* name
,
543 const elfcpp::Shdr
<size
, big_endian
>& shdr
)
545 if (shdr
.get_sh_flags() & elfcpp::SHF_EXCLUDE
)
548 switch (shdr
.get_sh_type())
550 case elfcpp::SHT_NULL
:
551 case elfcpp::SHT_SYMTAB
:
552 case elfcpp::SHT_DYNSYM
:
553 case elfcpp::SHT_HASH
:
554 case elfcpp::SHT_DYNAMIC
:
555 case elfcpp::SHT_SYMTAB_SHNDX
:
558 case elfcpp::SHT_STRTAB
:
559 // Discard the sections which have special meanings in the ELF
560 // ABI. Keep others (e.g., .stabstr). We could also do this by
561 // checking the sh_link fields of the appropriate sections.
562 return (strcmp(name
, ".dynstr") != 0
563 && strcmp(name
, ".strtab") != 0
564 && strcmp(name
, ".shstrtab") != 0);
566 case elfcpp::SHT_RELA
:
567 case elfcpp::SHT_REL
:
568 case elfcpp::SHT_GROUP
:
569 // If we are emitting relocations these should be handled
571 gold_assert(!parameters
->options().relocatable()
572 && !parameters
->options().emit_relocs());
575 case elfcpp::SHT_PROGBITS
:
576 if (parameters
->options().strip_debug()
577 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
579 if (is_debug_info_section(name
))
582 if (parameters
->options().strip_debug_non_line()
583 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
585 // Debugging sections can only be recognized by name.
586 if (is_prefix_of(".debug", name
)
587 && !is_lines_only_debug_section(name
))
590 if (parameters
->options().strip_debug_gdb()
591 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
593 // Debugging sections can only be recognized by name.
594 if (is_prefix_of(".debug", name
)
595 && !is_gdb_debug_section(name
))
598 if (parameters
->options().strip_lto_sections()
599 && !parameters
->options().relocatable()
600 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
602 // Ignore LTO sections containing intermediate code.
603 if (is_prefix_of(".gnu.lto_", name
))
606 // The GNU linker strips .gnu_debuglink sections, so we do too.
607 // This is a feature used to keep debugging information in
609 if (strcmp(name
, ".gnu_debuglink") == 0)
618 // Return an output section named NAME, or NULL if there is none.
621 Layout::find_output_section(const char* name
) const
623 for (Section_list::const_iterator p
= this->section_list_
.begin();
624 p
!= this->section_list_
.end();
626 if (strcmp((*p
)->name(), name
) == 0)
631 // Return an output segment of type TYPE, with segment flags SET set
632 // and segment flags CLEAR clear. Return NULL if there is none.
635 Layout::find_output_segment(elfcpp::PT type
, elfcpp::Elf_Word set
,
636 elfcpp::Elf_Word clear
) const
638 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
639 p
!= this->segment_list_
.end();
641 if (static_cast<elfcpp::PT
>((*p
)->type()) == type
642 && ((*p
)->flags() & set
) == set
643 && ((*p
)->flags() & clear
) == 0)
648 // When we put a .ctors or .dtors section with more than one word into
649 // a .init_array or .fini_array section, we need to reverse the words
650 // in the .ctors/.dtors section. This is because .init_array executes
651 // constructors front to back, where .ctors executes them back to
652 // front, and vice-versa for .fini_array/.dtors. Although we do want
653 // to remap .ctors/.dtors into .init_array/.fini_array because it can
654 // be more efficient, we don't want to change the order in which
655 // constructors/destructors are run. This set just keeps track of
656 // these sections which need to be reversed. It is only changed by
657 // Layout::layout. It should be a private member of Layout, but that
658 // would require layout.h to #include object.h to get the definition
660 static Unordered_set
<Section_id
, Section_id_hash
> ctors_sections_in_init_array
;
662 // Return whether OBJECT/SHNDX is a .ctors/.dtors section mapped to a
663 // .init_array/.fini_array section.
666 Layout::is_ctors_in_init_array(Relobj
* relobj
, unsigned int shndx
) const
668 return (ctors_sections_in_init_array
.find(Section_id(relobj
, shndx
))
669 != ctors_sections_in_init_array
.end());
672 // Return the output section to use for section NAME with type TYPE
673 // and section flags FLAGS. NAME must be canonicalized in the string
674 // pool, and NAME_KEY is the key. ORDER is where this should appear
675 // in the output sections. IS_RELRO is true for a relro section.
678 Layout::get_output_section(const char* name
, Stringpool::Key name_key
,
679 elfcpp::Elf_Word type
, elfcpp::Elf_Xword flags
,
680 Output_section_order order
, bool is_relro
)
682 elfcpp::Elf_Word lookup_type
= type
;
684 // For lookup purposes, treat INIT_ARRAY, FINI_ARRAY, and
685 // PREINIT_ARRAY like PROGBITS. This ensures that we combine
686 // .init_array, .fini_array, and .preinit_array sections by name
687 // whatever their type in the input file. We do this because the
688 // types are not always right in the input files.
689 if (lookup_type
== elfcpp::SHT_INIT_ARRAY
690 || lookup_type
== elfcpp::SHT_FINI_ARRAY
691 || lookup_type
== elfcpp::SHT_PREINIT_ARRAY
)
692 lookup_type
= elfcpp::SHT_PROGBITS
;
694 elfcpp::Elf_Xword lookup_flags
= flags
;
696 // Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine
697 // read-write with read-only sections. Some other ELF linkers do
698 // not do this. FIXME: Perhaps there should be an option
700 lookup_flags
&= ~(elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
);
702 const Key
key(name_key
, std::make_pair(lookup_type
, lookup_flags
));
703 const std::pair
<Key
, Output_section
*> v(key
, NULL
);
704 std::pair
<Section_name_map::iterator
, bool> ins(
705 this->section_name_map_
.insert(v
));
708 return ins
.first
->second
;
711 // This is the first time we've seen this name/type/flags
712 // combination. For compatibility with the GNU linker, we
713 // combine sections with contents and zero flags with sections
714 // with non-zero flags. This is a workaround for cases where
715 // assembler code forgets to set section flags. FIXME: Perhaps
716 // there should be an option to control this.
717 Output_section
* os
= NULL
;
719 if (lookup_type
== elfcpp::SHT_PROGBITS
)
723 Output_section
* same_name
= this->find_output_section(name
);
724 if (same_name
!= NULL
725 && (same_name
->type() == elfcpp::SHT_PROGBITS
726 || same_name
->type() == elfcpp::SHT_INIT_ARRAY
727 || same_name
->type() == elfcpp::SHT_FINI_ARRAY
728 || same_name
->type() == elfcpp::SHT_PREINIT_ARRAY
)
729 && (same_name
->flags() & elfcpp::SHF_TLS
) == 0)
732 else if ((flags
& elfcpp::SHF_TLS
) == 0)
734 elfcpp::Elf_Xword zero_flags
= 0;
735 const Key
zero_key(name_key
, std::make_pair(lookup_type
,
737 Section_name_map::iterator p
=
738 this->section_name_map_
.find(zero_key
);
739 if (p
!= this->section_name_map_
.end())
745 os
= this->make_output_section(name
, type
, flags
, order
, is_relro
);
747 ins
.first
->second
= os
;
752 // Pick the output section to use for section NAME, in input file
753 // RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a
754 // linker created section. IS_INPUT_SECTION is true if we are
755 // choosing an output section for an input section found in a input
756 // file. ORDER is where this section should appear in the output
757 // sections. IS_RELRO is true for a relro section. This will return
758 // NULL if the input section should be discarded.
761 Layout::choose_output_section(const Relobj
* relobj
, const char* name
,
762 elfcpp::Elf_Word type
, elfcpp::Elf_Xword flags
,
763 bool is_input_section
, Output_section_order order
,
766 // We should not see any input sections after we have attached
767 // sections to segments.
768 gold_assert(!is_input_section
|| !this->sections_are_attached_
);
770 // Some flags in the input section should not be automatically
771 // copied to the output section.
772 flags
&= ~ (elfcpp::SHF_INFO_LINK
775 | elfcpp::SHF_STRINGS
);
777 // We only clear the SHF_LINK_ORDER flag in for
778 // a non-relocatable link.
779 if (!parameters
->options().relocatable())
780 flags
&= ~elfcpp::SHF_LINK_ORDER
;
782 if (this->script_options_
->saw_sections_clause())
784 // We are using a SECTIONS clause, so the output section is
785 // chosen based only on the name.
787 Script_sections
* ss
= this->script_options_
->script_sections();
788 const char* file_name
= relobj
== NULL
? NULL
: relobj
->name().c_str();
789 Output_section
** output_section_slot
;
790 Script_sections::Section_type script_section_type
;
791 const char* orig_name
= name
;
792 name
= ss
->output_section_name(file_name
, name
, &output_section_slot
,
793 &script_section_type
);
796 gold_debug(DEBUG_SCRIPT
, _("Unable to create output section '%s' "
797 "because it is not allowed by the "
798 "SECTIONS clause of the linker script"),
800 // The SECTIONS clause says to discard this input section.
804 // We can only handle script section types ST_NONE and ST_NOLOAD.
805 switch (script_section_type
)
807 case Script_sections::ST_NONE
:
809 case Script_sections::ST_NOLOAD
:
810 flags
&= elfcpp::SHF_ALLOC
;
816 // If this is an orphan section--one not mentioned in the linker
817 // script--then OUTPUT_SECTION_SLOT will be NULL, and we do the
818 // default processing below.
820 if (output_section_slot
!= NULL
)
822 if (*output_section_slot
!= NULL
)
824 (*output_section_slot
)->update_flags_for_input_section(flags
);
825 return *output_section_slot
;
828 // We don't put sections found in the linker script into
829 // SECTION_NAME_MAP_. That keeps us from getting confused
830 // if an orphan section is mapped to a section with the same
831 // name as one in the linker script.
833 name
= this->namepool_
.add(name
, false, NULL
);
835 Output_section
* os
= this->make_output_section(name
, type
, flags
,
838 os
->set_found_in_sections_clause();
840 // Special handling for NOLOAD sections.
841 if (script_section_type
== Script_sections::ST_NOLOAD
)
845 // The constructor of Output_section sets addresses of non-ALLOC
846 // sections to 0 by default. We don't want that for NOLOAD
847 // sections even if they have no SHF_ALLOC flag.
848 if ((os
->flags() & elfcpp::SHF_ALLOC
) == 0
849 && os
->is_address_valid())
851 gold_assert(os
->address() == 0
852 && !os
->is_offset_valid()
853 && !os
->is_data_size_valid());
854 os
->reset_address_and_file_offset();
858 *output_section_slot
= os
;
863 // FIXME: Handle SHF_OS_NONCONFORMING somewhere.
865 size_t len
= strlen(name
);
866 char* uncompressed_name
= NULL
;
868 // Compressed debug sections should be mapped to the corresponding
869 // uncompressed section.
870 if (is_compressed_debug_section(name
))
872 uncompressed_name
= new char[len
];
873 uncompressed_name
[0] = '.';
874 gold_assert(name
[0] == '.' && name
[1] == 'z');
875 strncpy(&uncompressed_name
[1], &name
[2], len
- 2);
876 uncompressed_name
[len
- 1] = '\0';
878 name
= uncompressed_name
;
881 // Turn NAME from the name of the input section into the name of the
884 && !this->script_options_
->saw_sections_clause()
885 && !parameters
->options().relocatable())
886 name
= Layout::output_section_name(relobj
, name
, &len
);
888 Stringpool::Key name_key
;
889 name
= this->namepool_
.add_with_length(name
, len
, true, &name_key
);
891 if (uncompressed_name
!= NULL
)
892 delete[] uncompressed_name
;
894 // Find or make the output section. The output section is selected
895 // based on the section name, type, and flags.
896 return this->get_output_section(name
, name_key
, type
, flags
, order
, is_relro
);
899 // For incremental links, record the initial fixed layout of a section
900 // from the base file, and return a pointer to the Output_section.
902 template<int size
, bool big_endian
>
904 Layout::init_fixed_output_section(const char* name
,
905 elfcpp::Shdr
<size
, big_endian
>& shdr
)
907 unsigned int sh_type
= shdr
.get_sh_type();
909 // We preserve the layout of PROGBITS, NOBITS, INIT_ARRAY, FINI_ARRAY,
910 // PRE_INIT_ARRAY, and NOTE sections.
911 // All others will be created from scratch and reallocated.
912 if (!can_incremental_update(sh_type
))
915 // If we're generating a .gdb_index section, we need to regenerate
917 if (parameters
->options().gdb_index()
918 && sh_type
== elfcpp::SHT_PROGBITS
919 && strcmp(name
, ".gdb_index") == 0)
922 typename
elfcpp::Elf_types
<size
>::Elf_Addr sh_addr
= shdr
.get_sh_addr();
923 typename
elfcpp::Elf_types
<size
>::Elf_Off sh_offset
= shdr
.get_sh_offset();
924 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_size
= shdr
.get_sh_size();
925 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
926 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_addralign
=
927 shdr
.get_sh_addralign();
929 // Make the output section.
930 Stringpool::Key name_key
;
931 name
= this->namepool_
.add(name
, true, &name_key
);
932 Output_section
* os
= this->get_output_section(name
, name_key
, sh_type
,
933 sh_flags
, ORDER_INVALID
, false);
934 os
->set_fixed_layout(sh_addr
, sh_offset
, sh_size
, sh_addralign
);
935 if (sh_type
!= elfcpp::SHT_NOBITS
)
936 this->free_list_
.remove(sh_offset
, sh_offset
+ sh_size
);
940 // Return the output section to use for input section SHNDX, with name
941 // NAME, with header HEADER, from object OBJECT. RELOC_SHNDX is the
942 // index of a relocation section which applies to this section, or 0
943 // if none, or -1U if more than one. RELOC_TYPE is the type of the
944 // relocation section if there is one. Set *OFF to the offset of this
945 // input section without the output section. Return NULL if the
946 // section should be discarded. Set *OFF to -1 if the section
947 // contents should not be written directly to the output file, but
948 // will instead receive special handling.
950 template<int size
, bool big_endian
>
952 Layout::layout(Sized_relobj_file
<size
, big_endian
>* object
, unsigned int shndx
,
953 const char* name
, const elfcpp::Shdr
<size
, big_endian
>& shdr
,
954 unsigned int reloc_shndx
, unsigned int, off_t
* off
)
958 if (!this->include_section(object
, name
, shdr
))
961 elfcpp::Elf_Word sh_type
= shdr
.get_sh_type();
963 // In a relocatable link a grouped section must not be combined with
964 // any other sections.
966 if (parameters
->options().relocatable()
967 && (shdr
.get_sh_flags() & elfcpp::SHF_GROUP
) != 0)
969 name
= this->namepool_
.add(name
, true, NULL
);
970 os
= this->make_output_section(name
, sh_type
, shdr
.get_sh_flags(),
971 ORDER_INVALID
, false);
975 os
= this->choose_output_section(object
, name
, sh_type
,
976 shdr
.get_sh_flags(), true,
977 ORDER_INVALID
, false);
982 // By default the GNU linker sorts input sections whose names match
983 // .ctors.*, .dtors.*, .init_array.*, or .fini_array.*. The
984 // sections are sorted by name. This is used to implement
985 // constructor priority ordering. We are compatible. When we put
986 // .ctor sections in .init_array and .dtor sections in .fini_array,
987 // we must also sort plain .ctor and .dtor sections.
988 if (!this->script_options_
->saw_sections_clause()
989 && !parameters
->options().relocatable()
990 && (is_prefix_of(".ctors.", name
)
991 || is_prefix_of(".dtors.", name
)
992 || is_prefix_of(".init_array.", name
)
993 || is_prefix_of(".fini_array.", name
)
994 || (parameters
->options().ctors_in_init_array()
995 && (strcmp(name
, ".ctors") == 0
996 || strcmp(name
, ".dtors") == 0))))
997 os
->set_must_sort_attached_input_sections();
999 // If this is a .ctors or .ctors.* section being mapped to a
1000 // .init_array section, or a .dtors or .dtors.* section being mapped
1001 // to a .fini_array section, we will need to reverse the words if
1002 // there is more than one. Record this section for later. See
1003 // ctors_sections_in_init_array above.
1004 if (!this->script_options_
->saw_sections_clause()
1005 && !parameters
->options().relocatable()
1006 && shdr
.get_sh_size() > size
/ 8
1007 && (((strcmp(name
, ".ctors") == 0
1008 || is_prefix_of(".ctors.", name
))
1009 && strcmp(os
->name(), ".init_array") == 0)
1010 || ((strcmp(name
, ".dtors") == 0
1011 || is_prefix_of(".dtors.", name
))
1012 && strcmp(os
->name(), ".fini_array") == 0)))
1013 ctors_sections_in_init_array
.insert(Section_id(object
, shndx
));
1015 // FIXME: Handle SHF_LINK_ORDER somewhere.
1017 elfcpp::Elf_Xword orig_flags
= os
->flags();
1019 *off
= os
->add_input_section(this, object
, shndx
, name
, shdr
, reloc_shndx
,
1020 this->script_options_
->saw_sections_clause());
1022 // If the flags changed, we may have to change the order.
1023 if ((orig_flags
& elfcpp::SHF_ALLOC
) != 0)
1025 orig_flags
&= (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
);
1026 elfcpp::Elf_Xword new_flags
=
1027 os
->flags() & (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
);
1028 if (orig_flags
!= new_flags
)
1029 os
->set_order(this->default_section_order(os
, false));
1032 this->have_added_input_section_
= true;
1037 // Handle a relocation section when doing a relocatable link.
1039 template<int size
, bool big_endian
>
1041 Layout::layout_reloc(Sized_relobj_file
<size
, big_endian
>* object
,
1043 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1044 Output_section
* data_section
,
1045 Relocatable_relocs
* rr
)
1047 gold_assert(parameters
->options().relocatable()
1048 || parameters
->options().emit_relocs());
1050 int sh_type
= shdr
.get_sh_type();
1053 if (sh_type
== elfcpp::SHT_REL
)
1055 else if (sh_type
== elfcpp::SHT_RELA
)
1059 name
+= data_section
->name();
1061 // In a relocatable link relocs for a grouped section must not be
1062 // combined with other reloc sections.
1064 if (!parameters
->options().relocatable()
1065 || (data_section
->flags() & elfcpp::SHF_GROUP
) == 0)
1066 os
= this->choose_output_section(object
, name
.c_str(), sh_type
,
1067 shdr
.get_sh_flags(), false,
1068 ORDER_INVALID
, false);
1071 const char* n
= this->namepool_
.add(name
.c_str(), true, NULL
);
1072 os
= this->make_output_section(n
, sh_type
, shdr
.get_sh_flags(),
1073 ORDER_INVALID
, false);
1076 os
->set_should_link_to_symtab();
1077 os
->set_info_section(data_section
);
1079 Output_section_data
* posd
;
1080 if (sh_type
== elfcpp::SHT_REL
)
1082 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
1083 posd
= new Output_relocatable_relocs
<elfcpp::SHT_REL
,
1087 else if (sh_type
== elfcpp::SHT_RELA
)
1089 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
1090 posd
= new Output_relocatable_relocs
<elfcpp::SHT_RELA
,
1097 os
->add_output_section_data(posd
);
1098 rr
->set_output_data(posd
);
1103 // Handle a group section when doing a relocatable link.
1105 template<int size
, bool big_endian
>
1107 Layout::layout_group(Symbol_table
* symtab
,
1108 Sized_relobj_file
<size
, big_endian
>* object
,
1110 const char* group_section_name
,
1111 const char* signature
,
1112 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1113 elfcpp::Elf_Word flags
,
1114 std::vector
<unsigned int>* shndxes
)
1116 gold_assert(parameters
->options().relocatable());
1117 gold_assert(shdr
.get_sh_type() == elfcpp::SHT_GROUP
);
1118 group_section_name
= this->namepool_
.add(group_section_name
, true, NULL
);
1119 Output_section
* os
= this->make_output_section(group_section_name
,
1121 shdr
.get_sh_flags(),
1122 ORDER_INVALID
, false);
1124 // We need to find a symbol with the signature in the symbol table.
1125 // If we don't find one now, we need to look again later.
1126 Symbol
* sym
= symtab
->lookup(signature
, NULL
);
1128 os
->set_info_symndx(sym
);
1131 // Reserve some space to minimize reallocations.
1132 if (this->group_signatures_
.empty())
1133 this->group_signatures_
.reserve(this->number_of_input_files_
* 16);
1135 // We will wind up using a symbol whose name is the signature.
1136 // So just put the signature in the symbol name pool to save it.
1137 signature
= symtab
->canonicalize_name(signature
);
1138 this->group_signatures_
.push_back(Group_signature(os
, signature
));
1141 os
->set_should_link_to_symtab();
1144 section_size_type entry_count
=
1145 convert_to_section_size_type(shdr
.get_sh_size() / 4);
1146 Output_section_data
* posd
=
1147 new Output_data_group
<size
, big_endian
>(object
, entry_count
, flags
,
1149 os
->add_output_section_data(posd
);
1152 // Special GNU handling of sections name .eh_frame. They will
1153 // normally hold exception frame data as defined by the C++ ABI
1154 // (http://codesourcery.com/cxx-abi/).
1156 template<int size
, bool big_endian
>
1158 Layout::layout_eh_frame(Sized_relobj_file
<size
, big_endian
>* object
,
1159 const unsigned char* symbols
,
1161 const unsigned char* symbol_names
,
1162 off_t symbol_names_size
,
1164 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1165 unsigned int reloc_shndx
, unsigned int reloc_type
,
1168 gold_assert(shdr
.get_sh_type() == elfcpp::SHT_PROGBITS
1169 || shdr
.get_sh_type() == elfcpp::SHT_X86_64_UNWIND
);
1170 gold_assert((shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) != 0);
1172 Output_section
* os
= this->make_eh_frame_section(object
);
1176 gold_assert(this->eh_frame_section_
== os
);
1178 elfcpp::Elf_Xword orig_flags
= os
->flags();
1180 if (!parameters
->incremental()
1181 && this->eh_frame_data_
->add_ehframe_input_section(object
,
1190 os
->update_flags_for_input_section(shdr
.get_sh_flags());
1192 // A writable .eh_frame section is a RELRO section.
1193 if ((orig_flags
& (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
))
1194 != (os
->flags() & (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
)))
1197 os
->set_order(ORDER_RELRO
);
1200 // We found a .eh_frame section we are going to optimize, so now
1201 // we can add the set of optimized sections to the output
1202 // section. We need to postpone adding this until we've found a
1203 // section we can optimize so that the .eh_frame section in
1204 // crtbegin.o winds up at the start of the output section.
1205 if (!this->added_eh_frame_data_
)
1207 os
->add_output_section_data(this->eh_frame_data_
);
1208 this->added_eh_frame_data_
= true;
1214 // We couldn't handle this .eh_frame section for some reason.
1215 // Add it as a normal section.
1216 bool saw_sections_clause
= this->script_options_
->saw_sections_clause();
1217 *off
= os
->add_input_section(this, object
, shndx
, ".eh_frame", shdr
,
1218 reloc_shndx
, saw_sections_clause
);
1219 this->have_added_input_section_
= true;
1221 if ((orig_flags
& (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
))
1222 != (os
->flags() & (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
)))
1223 os
->set_order(this->default_section_order(os
, false));
1229 // Create and return the magic .eh_frame section. Create
1230 // .eh_frame_hdr also if appropriate. OBJECT is the object with the
1231 // input .eh_frame section; it may be NULL.
1234 Layout::make_eh_frame_section(const Relobj
* object
)
1236 // FIXME: On x86_64, this could use SHT_X86_64_UNWIND rather than
1238 Output_section
* os
= this->choose_output_section(object
, ".eh_frame",
1239 elfcpp::SHT_PROGBITS
,
1240 elfcpp::SHF_ALLOC
, false,
1241 ORDER_EHFRAME
, false);
1245 if (this->eh_frame_section_
== NULL
)
1247 this->eh_frame_section_
= os
;
1248 this->eh_frame_data_
= new Eh_frame();
1250 // For incremental linking, we do not optimize .eh_frame sections
1251 // or create a .eh_frame_hdr section.
1252 if (parameters
->options().eh_frame_hdr() && !parameters
->incremental())
1254 Output_section
* hdr_os
=
1255 this->choose_output_section(NULL
, ".eh_frame_hdr",
1256 elfcpp::SHT_PROGBITS
,
1257 elfcpp::SHF_ALLOC
, false,
1258 ORDER_EHFRAME
, false);
1262 Eh_frame_hdr
* hdr_posd
= new Eh_frame_hdr(os
,
1263 this->eh_frame_data_
);
1264 hdr_os
->add_output_section_data(hdr_posd
);
1266 hdr_os
->set_after_input_sections();
1268 if (!this->script_options_
->saw_phdrs_clause())
1270 Output_segment
* hdr_oseg
;
1271 hdr_oseg
= this->make_output_segment(elfcpp::PT_GNU_EH_FRAME
,
1273 hdr_oseg
->add_output_section_to_nonload(hdr_os
,
1277 this->eh_frame_data_
->set_eh_frame_hdr(hdr_posd
);
1285 // Add an exception frame for a PLT. This is called from target code.
1288 Layout::add_eh_frame_for_plt(Output_data
* plt
, const unsigned char* cie_data
,
1289 size_t cie_length
, const unsigned char* fde_data
,
1292 if (parameters
->incremental())
1294 // FIXME: Maybe this could work some day....
1297 Output_section
* os
= this->make_eh_frame_section(NULL
);
1300 this->eh_frame_data_
->add_ehframe_for_plt(plt
, cie_data
, cie_length
,
1301 fde_data
, fde_length
);
1302 if (!this->added_eh_frame_data_
)
1304 os
->add_output_section_data(this->eh_frame_data_
);
1305 this->added_eh_frame_data_
= true;
1309 // Scan a .debug_info or .debug_types section, and add summary
1310 // information to the .gdb_index section.
1312 template<int size
, bool big_endian
>
1314 Layout::add_to_gdb_index(bool is_type_unit
,
1315 Sized_relobj
<size
, big_endian
>* object
,
1316 const unsigned char* symbols
,
1319 unsigned int reloc_shndx
,
1320 unsigned int reloc_type
)
1322 if (this->gdb_index_data_
== NULL
)
1324 Output_section
* os
= this->choose_output_section(NULL
, ".gdb_index",
1325 elfcpp::SHT_PROGBITS
, 0,
1326 false, ORDER_INVALID
,
1331 this->gdb_index_data_
= new Gdb_index(os
);
1332 os
->add_output_section_data(this->gdb_index_data_
);
1333 os
->set_after_input_sections();
1336 this->gdb_index_data_
->scan_debug_info(is_type_unit
, object
, symbols
,
1337 symbols_size
, shndx
, reloc_shndx
,
1341 // Add POSD to an output section using NAME, TYPE, and FLAGS. Return
1342 // the output section.
1345 Layout::add_output_section_data(const char* name
, elfcpp::Elf_Word type
,
1346 elfcpp::Elf_Xword flags
,
1347 Output_section_data
* posd
,
1348 Output_section_order order
, bool is_relro
)
1350 Output_section
* os
= this->choose_output_section(NULL
, name
, type
, flags
,
1351 false, order
, is_relro
);
1353 os
->add_output_section_data(posd
);
1357 // Map section flags to segment flags.
1360 Layout::section_flags_to_segment(elfcpp::Elf_Xword flags
)
1362 elfcpp::Elf_Word ret
= elfcpp::PF_R
;
1363 if ((flags
& elfcpp::SHF_WRITE
) != 0)
1364 ret
|= elfcpp::PF_W
;
1365 if ((flags
& elfcpp::SHF_EXECINSTR
) != 0)
1366 ret
|= elfcpp::PF_X
;
1370 // Make a new Output_section, and attach it to segments as
1371 // appropriate. ORDER is the order in which this section should
1372 // appear in the output segment. IS_RELRO is true if this is a relro
1373 // (read-only after relocations) section.
1376 Layout::make_output_section(const char* name
, elfcpp::Elf_Word type
,
1377 elfcpp::Elf_Xword flags
,
1378 Output_section_order order
, bool is_relro
)
1381 if ((flags
& elfcpp::SHF_ALLOC
) == 0
1382 && strcmp(parameters
->options().compress_debug_sections(), "none") != 0
1383 && is_compressible_debug_section(name
))
1384 os
= new Output_compressed_section(¶meters
->options(), name
, type
,
1386 else if ((flags
& elfcpp::SHF_ALLOC
) == 0
1387 && parameters
->options().strip_debug_non_line()
1388 && strcmp(".debug_abbrev", name
) == 0)
1390 os
= this->debug_abbrev_
= new Output_reduced_debug_abbrev_section(
1392 if (this->debug_info_
)
1393 this->debug_info_
->set_abbreviations(this->debug_abbrev_
);
1395 else if ((flags
& elfcpp::SHF_ALLOC
) == 0
1396 && parameters
->options().strip_debug_non_line()
1397 && strcmp(".debug_info", name
) == 0)
1399 os
= this->debug_info_
= new Output_reduced_debug_info_section(
1401 if (this->debug_abbrev_
)
1402 this->debug_info_
->set_abbreviations(this->debug_abbrev_
);
1406 // Sometimes .init_array*, .preinit_array* and .fini_array* do
1407 // not have correct section types. Force them here.
1408 if (type
== elfcpp::SHT_PROGBITS
)
1410 if (is_prefix_of(".init_array", name
))
1411 type
= elfcpp::SHT_INIT_ARRAY
;
1412 else if (is_prefix_of(".preinit_array", name
))
1413 type
= elfcpp::SHT_PREINIT_ARRAY
;
1414 else if (is_prefix_of(".fini_array", name
))
1415 type
= elfcpp::SHT_FINI_ARRAY
;
1418 // FIXME: const_cast is ugly.
1419 Target
* target
= const_cast<Target
*>(¶meters
->target());
1420 os
= target
->make_output_section(name
, type
, flags
);
1423 // With -z relro, we have to recognize the special sections by name.
1424 // There is no other way.
1425 bool is_relro_local
= false;
1426 if (!this->script_options_
->saw_sections_clause()
1427 && parameters
->options().relro()
1428 && (flags
& elfcpp::SHF_ALLOC
) != 0
1429 && (flags
& elfcpp::SHF_WRITE
) != 0)
1431 if (type
== elfcpp::SHT_PROGBITS
)
1433 if (strcmp(name
, ".data.rel.ro") == 0)
1435 else if (strcmp(name
, ".data.rel.ro.local") == 0)
1438 is_relro_local
= true;
1440 else if (strcmp(name
, ".ctors") == 0
1441 || strcmp(name
, ".dtors") == 0
1442 || strcmp(name
, ".jcr") == 0)
1445 else if (type
== elfcpp::SHT_INIT_ARRAY
1446 || type
== elfcpp::SHT_FINI_ARRAY
1447 || type
== elfcpp::SHT_PREINIT_ARRAY
)
1454 if (order
== ORDER_INVALID
&& (flags
& elfcpp::SHF_ALLOC
) != 0)
1455 order
= this->default_section_order(os
, is_relro_local
);
1457 os
->set_order(order
);
1459 parameters
->target().new_output_section(os
);
1461 this->section_list_
.push_back(os
);
1463 // The GNU linker by default sorts some sections by priority, so we
1464 // do the same. We need to know that this might happen before we
1465 // attach any input sections.
1466 if (!this->script_options_
->saw_sections_clause()
1467 && !parameters
->options().relocatable()
1468 && (strcmp(name
, ".init_array") == 0
1469 || strcmp(name
, ".fini_array") == 0
1470 || (!parameters
->options().ctors_in_init_array()
1471 && (strcmp(name
, ".ctors") == 0
1472 || strcmp(name
, ".dtors") == 0))))
1473 os
->set_may_sort_attached_input_sections();
1475 // Check for .stab*str sections, as .stab* sections need to link to
1477 if (type
== elfcpp::SHT_STRTAB
1478 && !this->have_stabstr_section_
1479 && strncmp(name
, ".stab", 5) == 0
1480 && strcmp(name
+ strlen(name
) - 3, "str") == 0)
1481 this->have_stabstr_section_
= true;
1483 // During a full incremental link, we add patch space to most
1484 // PROGBITS and NOBITS sections. Flag those that may be
1485 // arbitrarily padded.
1486 if ((type
== elfcpp::SHT_PROGBITS
|| type
== elfcpp::SHT_NOBITS
)
1487 && order
!= ORDER_INTERP
1488 && order
!= ORDER_INIT
1489 && order
!= ORDER_PLT
1490 && order
!= ORDER_FINI
1491 && order
!= ORDER_RELRO_LAST
1492 && order
!= ORDER_NON_RELRO_FIRST
1493 && strcmp(name
, ".eh_frame") != 0
1494 && strcmp(name
, ".ctors") != 0
1495 && strcmp(name
, ".dtors") != 0
1496 && strcmp(name
, ".jcr") != 0)
1498 os
->set_is_patch_space_allowed();
1500 // Certain sections require "holes" to be filled with
1501 // specific fill patterns. These fill patterns may have
1502 // a minimum size, so we must prevent allocations from the
1503 // free list that leave a hole smaller than the minimum.
1504 if (strcmp(name
, ".debug_info") == 0)
1505 os
->set_free_space_fill(new Output_fill_debug_info(false));
1506 else if (strcmp(name
, ".debug_types") == 0)
1507 os
->set_free_space_fill(new Output_fill_debug_info(true));
1508 else if (strcmp(name
, ".debug_line") == 0)
1509 os
->set_free_space_fill(new Output_fill_debug_line());
1512 // If we have already attached the sections to segments, then we
1513 // need to attach this one now. This happens for sections created
1514 // directly by the linker.
1515 if (this->sections_are_attached_
)
1516 this->attach_section_to_segment(¶meters
->target(), os
);
1521 // Return the default order in which a section should be placed in an
1522 // output segment. This function captures a lot of the ideas in
1523 // ld/scripttempl/elf.sc in the GNU linker. Note that the order of a
1524 // linker created section is normally set when the section is created;
1525 // this function is used for input sections.
1527 Output_section_order
1528 Layout::default_section_order(Output_section
* os
, bool is_relro_local
)
1530 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
1531 bool is_write
= (os
->flags() & elfcpp::SHF_WRITE
) != 0;
1532 bool is_execinstr
= (os
->flags() & elfcpp::SHF_EXECINSTR
) != 0;
1533 bool is_bss
= false;
1538 case elfcpp::SHT_PROGBITS
:
1540 case elfcpp::SHT_NOBITS
:
1543 case elfcpp::SHT_RELA
:
1544 case elfcpp::SHT_REL
:
1546 return ORDER_DYNAMIC_RELOCS
;
1548 case elfcpp::SHT_HASH
:
1549 case elfcpp::SHT_DYNAMIC
:
1550 case elfcpp::SHT_SHLIB
:
1551 case elfcpp::SHT_DYNSYM
:
1552 case elfcpp::SHT_GNU_HASH
:
1553 case elfcpp::SHT_GNU_verdef
:
1554 case elfcpp::SHT_GNU_verneed
:
1555 case elfcpp::SHT_GNU_versym
:
1557 return ORDER_DYNAMIC_LINKER
;
1559 case elfcpp::SHT_NOTE
:
1560 return is_write
? ORDER_RW_NOTE
: ORDER_RO_NOTE
;
1563 if ((os
->flags() & elfcpp::SHF_TLS
) != 0)
1564 return is_bss
? ORDER_TLS_BSS
: ORDER_TLS_DATA
;
1566 if (!is_bss
&& !is_write
)
1570 if (strcmp(os
->name(), ".init") == 0)
1572 else if (strcmp(os
->name(), ".fini") == 0)
1575 return is_execinstr
? ORDER_TEXT
: ORDER_READONLY
;
1579 return is_relro_local
? ORDER_RELRO_LOCAL
: ORDER_RELRO
;
1581 if (os
->is_small_section())
1582 return is_bss
? ORDER_SMALL_BSS
: ORDER_SMALL_DATA
;
1583 if (os
->is_large_section())
1584 return is_bss
? ORDER_LARGE_BSS
: ORDER_LARGE_DATA
;
1586 return is_bss
? ORDER_BSS
: ORDER_DATA
;
1589 // Attach output sections to segments. This is called after we have
1590 // seen all the input sections.
1593 Layout::attach_sections_to_segments(const Target
* target
)
1595 for (Section_list::iterator p
= this->section_list_
.begin();
1596 p
!= this->section_list_
.end();
1598 this->attach_section_to_segment(target
, *p
);
1600 this->sections_are_attached_
= true;
1603 // Attach an output section to a segment.
1606 Layout::attach_section_to_segment(const Target
* target
, Output_section
* os
)
1608 if ((os
->flags() & elfcpp::SHF_ALLOC
) == 0)
1609 this->unattached_section_list_
.push_back(os
);
1611 this->attach_allocated_section_to_segment(target
, os
);
1614 // Attach an allocated output section to a segment.
1617 Layout::attach_allocated_section_to_segment(const Target
* target
,
1620 elfcpp::Elf_Xword flags
= os
->flags();
1621 gold_assert((flags
& elfcpp::SHF_ALLOC
) != 0);
1623 if (parameters
->options().relocatable())
1626 // If we have a SECTIONS clause, we can't handle the attachment to
1627 // segments until after we've seen all the sections.
1628 if (this->script_options_
->saw_sections_clause())
1631 gold_assert(!this->script_options_
->saw_phdrs_clause());
1633 // This output section goes into a PT_LOAD segment.
1635 elfcpp::Elf_Word seg_flags
= Layout::section_flags_to_segment(flags
);
1637 // Check for --section-start.
1639 bool is_address_set
= parameters
->options().section_start(os
->name(), &addr
);
1641 // In general the only thing we really care about for PT_LOAD
1642 // segments is whether or not they are writable or executable,
1643 // so that is how we search for them.
1644 // Large data sections also go into their own PT_LOAD segment.
1645 // People who need segments sorted on some other basis will
1646 // have to use a linker script.
1648 Segment_list::const_iterator p
;
1649 for (p
= this->segment_list_
.begin();
1650 p
!= this->segment_list_
.end();
1653 if ((*p
)->type() != elfcpp::PT_LOAD
)
1655 if (!parameters
->options().omagic()
1656 && ((*p
)->flags() & elfcpp::PF_W
) != (seg_flags
& elfcpp::PF_W
))
1658 if ((target
->isolate_execinstr() || parameters
->options().rosegment())
1659 && ((*p
)->flags() & elfcpp::PF_X
) != (seg_flags
& elfcpp::PF_X
))
1661 // If -Tbss was specified, we need to separate the data and BSS
1663 if (parameters
->options().user_set_Tbss())
1665 if ((os
->type() == elfcpp::SHT_NOBITS
)
1666 == (*p
)->has_any_data_sections())
1669 if (os
->is_large_data_section() && !(*p
)->is_large_data_segment())
1674 if ((*p
)->are_addresses_set())
1677 (*p
)->add_initial_output_data(os
);
1678 (*p
)->update_flags_for_output_section(seg_flags
);
1679 (*p
)->set_addresses(addr
, addr
);
1683 (*p
)->add_output_section_to_load(this, os
, seg_flags
);
1687 if (p
== this->segment_list_
.end())
1689 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_LOAD
,
1691 if (os
->is_large_data_section())
1692 oseg
->set_is_large_data_segment();
1693 oseg
->add_output_section_to_load(this, os
, seg_flags
);
1695 oseg
->set_addresses(addr
, addr
);
1698 // If we see a loadable SHT_NOTE section, we create a PT_NOTE
1700 if (os
->type() == elfcpp::SHT_NOTE
)
1702 // See if we already have an equivalent PT_NOTE segment.
1703 for (p
= this->segment_list_
.begin();
1704 p
!= segment_list_
.end();
1707 if ((*p
)->type() == elfcpp::PT_NOTE
1708 && (((*p
)->flags() & elfcpp::PF_W
)
1709 == (seg_flags
& elfcpp::PF_W
)))
1711 (*p
)->add_output_section_to_nonload(os
, seg_flags
);
1716 if (p
== this->segment_list_
.end())
1718 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_NOTE
,
1720 oseg
->add_output_section_to_nonload(os
, seg_flags
);
1724 // If we see a loadable SHF_TLS section, we create a PT_TLS
1725 // segment. There can only be one such segment.
1726 if ((flags
& elfcpp::SHF_TLS
) != 0)
1728 if (this->tls_segment_
== NULL
)
1729 this->make_output_segment(elfcpp::PT_TLS
, seg_flags
);
1730 this->tls_segment_
->add_output_section_to_nonload(os
, seg_flags
);
1733 // If -z relro is in effect, and we see a relro section, we create a
1734 // PT_GNU_RELRO segment. There can only be one such segment.
1735 if (os
->is_relro() && parameters
->options().relro())
1737 gold_assert(seg_flags
== (elfcpp::PF_R
| elfcpp::PF_W
));
1738 if (this->relro_segment_
== NULL
)
1739 this->make_output_segment(elfcpp::PT_GNU_RELRO
, seg_flags
);
1740 this->relro_segment_
->add_output_section_to_nonload(os
, seg_flags
);
1743 // If we see a section named .interp, put it into a PT_INTERP
1744 // segment. This seems broken to me, but this is what GNU ld does,
1745 // and glibc expects it.
1746 if (strcmp(os
->name(), ".interp") == 0
1747 && !this->script_options_
->saw_phdrs_clause())
1749 if (this->interp_segment_
== NULL
)
1750 this->make_output_segment(elfcpp::PT_INTERP
, seg_flags
);
1752 gold_warning(_("multiple '.interp' sections in input files "
1753 "may cause confusing PT_INTERP segment"));
1754 this->interp_segment_
->add_output_section_to_nonload(os
, seg_flags
);
1758 // Make an output section for a script.
1761 Layout::make_output_section_for_script(
1763 Script_sections::Section_type section_type
)
1765 name
= this->namepool_
.add(name
, false, NULL
);
1766 elfcpp::Elf_Xword sh_flags
= elfcpp::SHF_ALLOC
;
1767 if (section_type
== Script_sections::ST_NOLOAD
)
1769 Output_section
* os
= this->make_output_section(name
, elfcpp::SHT_PROGBITS
,
1770 sh_flags
, ORDER_INVALID
,
1772 os
->set_found_in_sections_clause();
1773 if (section_type
== Script_sections::ST_NOLOAD
)
1774 os
->set_is_noload();
1778 // Return the number of segments we expect to see.
1781 Layout::expected_segment_count() const
1783 size_t ret
= this->segment_list_
.size();
1785 // If we didn't see a SECTIONS clause in a linker script, we should
1786 // already have the complete list of segments. Otherwise we ask the
1787 // SECTIONS clause how many segments it expects, and add in the ones
1788 // we already have (PT_GNU_STACK, PT_GNU_EH_FRAME, etc.)
1790 if (!this->script_options_
->saw_sections_clause())
1794 const Script_sections
* ss
= this->script_options_
->script_sections();
1795 return ret
+ ss
->expected_segment_count(this);
1799 // Handle the .note.GNU-stack section at layout time. SEEN_GNU_STACK
1800 // is whether we saw a .note.GNU-stack section in the object file.
1801 // GNU_STACK_FLAGS is the section flags. The flags give the
1802 // protection required for stack memory. We record this in an
1803 // executable as a PT_GNU_STACK segment. If an object file does not
1804 // have a .note.GNU-stack segment, we must assume that it is an old
1805 // object. On some targets that will force an executable stack.
1808 Layout::layout_gnu_stack(bool seen_gnu_stack
, uint64_t gnu_stack_flags
,
1811 if (!seen_gnu_stack
)
1813 this->input_without_gnu_stack_note_
= true;
1814 if (parameters
->options().warn_execstack()
1815 && parameters
->target().is_default_stack_executable())
1816 gold_warning(_("%s: missing .note.GNU-stack section"
1817 " implies executable stack"),
1818 obj
->name().c_str());
1822 this->input_with_gnu_stack_note_
= true;
1823 if ((gnu_stack_flags
& elfcpp::SHF_EXECINSTR
) != 0)
1825 this->input_requires_executable_stack_
= true;
1826 if (parameters
->options().warn_execstack()
1827 || parameters
->options().is_stack_executable())
1828 gold_warning(_("%s: requires executable stack"),
1829 obj
->name().c_str());
1834 // Create automatic note sections.
1837 Layout::create_notes()
1839 this->create_gold_note();
1840 this->create_executable_stack_info();
1841 this->create_build_id();
1844 // Create the dynamic sections which are needed before we read the
1848 Layout::create_initial_dynamic_sections(Symbol_table
* symtab
)
1850 if (parameters
->doing_static_link())
1853 this->dynamic_section_
= this->choose_output_section(NULL
, ".dynamic",
1854 elfcpp::SHT_DYNAMIC
,
1856 | elfcpp::SHF_WRITE
),
1860 // A linker script may discard .dynamic, so check for NULL.
1861 if (this->dynamic_section_
!= NULL
)
1863 this->dynamic_symbol_
=
1864 symtab
->define_in_output_data("_DYNAMIC", NULL
,
1865 Symbol_table::PREDEFINED
,
1866 this->dynamic_section_
, 0, 0,
1867 elfcpp::STT_OBJECT
, elfcpp::STB_LOCAL
,
1868 elfcpp::STV_HIDDEN
, 0, false, false);
1870 this->dynamic_data_
= new Output_data_dynamic(&this->dynpool_
);
1872 this->dynamic_section_
->add_output_section_data(this->dynamic_data_
);
1876 // For each output section whose name can be represented as C symbol,
1877 // define __start and __stop symbols for the section. This is a GNU
1881 Layout::define_section_symbols(Symbol_table
* symtab
)
1883 for (Section_list::const_iterator p
= this->section_list_
.begin();
1884 p
!= this->section_list_
.end();
1887 const char* const name
= (*p
)->name();
1888 if (is_cident(name
))
1890 const std::string
name_string(name
);
1891 const std::string
start_name(cident_section_start_prefix
1893 const std::string
stop_name(cident_section_stop_prefix
1896 symtab
->define_in_output_data(start_name
.c_str(),
1898 Symbol_table::PREDEFINED
,
1904 elfcpp::STV_DEFAULT
,
1906 false, // offset_is_from_end
1907 true); // only_if_ref
1909 symtab
->define_in_output_data(stop_name
.c_str(),
1911 Symbol_table::PREDEFINED
,
1917 elfcpp::STV_DEFAULT
,
1919 true, // offset_is_from_end
1920 true); // only_if_ref
1925 // Define symbols for group signatures.
1928 Layout::define_group_signatures(Symbol_table
* symtab
)
1930 for (Group_signatures::iterator p
= this->group_signatures_
.begin();
1931 p
!= this->group_signatures_
.end();
1934 Symbol
* sym
= symtab
->lookup(p
->signature
, NULL
);
1936 p
->section
->set_info_symndx(sym
);
1939 // Force the name of the group section to the group
1940 // signature, and use the group's section symbol as the
1941 // signature symbol.
1942 if (strcmp(p
->section
->name(), p
->signature
) != 0)
1944 const char* name
= this->namepool_
.add(p
->signature
,
1946 p
->section
->set_name(name
);
1948 p
->section
->set_needs_symtab_index();
1949 p
->section
->set_info_section_symndx(p
->section
);
1953 this->group_signatures_
.clear();
1956 // Find the first read-only PT_LOAD segment, creating one if
1960 Layout::find_first_load_seg(const Target
* target
)
1962 Output_segment
* best
= NULL
;
1963 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
1964 p
!= this->segment_list_
.end();
1967 if ((*p
)->type() == elfcpp::PT_LOAD
1968 && ((*p
)->flags() & elfcpp::PF_R
) != 0
1969 && (parameters
->options().omagic()
1970 || ((*p
)->flags() & elfcpp::PF_W
) == 0)
1971 && (!target
->isolate_execinstr()
1972 || ((*p
)->flags() & elfcpp::PF_X
) == 0))
1974 if (best
== NULL
|| this->segment_precedes(*p
, best
))
1981 gold_assert(!this->script_options_
->saw_phdrs_clause());
1983 Output_segment
* load_seg
= this->make_output_segment(elfcpp::PT_LOAD
,
1988 // Save states of all current output segments. Store saved states
1989 // in SEGMENT_STATES.
1992 Layout::save_segments(Segment_states
* segment_states
)
1994 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
1995 p
!= this->segment_list_
.end();
1998 Output_segment
* segment
= *p
;
2000 Output_segment
* copy
= new Output_segment(*segment
);
2001 (*segment_states
)[segment
] = copy
;
2005 // Restore states of output segments and delete any segment not found in
2009 Layout::restore_segments(const Segment_states
* segment_states
)
2011 // Go through the segment list and remove any segment added in the
2013 this->tls_segment_
= NULL
;
2014 this->relro_segment_
= NULL
;
2015 Segment_list::iterator list_iter
= this->segment_list_
.begin();
2016 while (list_iter
!= this->segment_list_
.end())
2018 Output_segment
* segment
= *list_iter
;
2019 Segment_states::const_iterator states_iter
=
2020 segment_states
->find(segment
);
2021 if (states_iter
!= segment_states
->end())
2023 const Output_segment
* copy
= states_iter
->second
;
2024 // Shallow copy to restore states.
2027 // Also fix up TLS and RELRO segment pointers as appropriate.
2028 if (segment
->type() == elfcpp::PT_TLS
)
2029 this->tls_segment_
= segment
;
2030 else if (segment
->type() == elfcpp::PT_GNU_RELRO
)
2031 this->relro_segment_
= segment
;
2037 list_iter
= this->segment_list_
.erase(list_iter
);
2038 // This is a segment created during section layout. It should be
2039 // safe to remove it since we should have removed all pointers to it.
2045 // Clean up after relaxation so that sections can be laid out again.
2048 Layout::clean_up_after_relaxation()
2050 // Restore the segments to point state just prior to the relaxation loop.
2051 Script_sections
* script_section
= this->script_options_
->script_sections();
2052 script_section
->release_segments();
2053 this->restore_segments(this->segment_states_
);
2055 // Reset section addresses and file offsets
2056 for (Section_list::iterator p
= this->section_list_
.begin();
2057 p
!= this->section_list_
.end();
2060 (*p
)->restore_states();
2062 // If an input section changes size because of relaxation,
2063 // we need to adjust the section offsets of all input sections.
2064 // after such a section.
2065 if ((*p
)->section_offsets_need_adjustment())
2066 (*p
)->adjust_section_offsets();
2068 (*p
)->reset_address_and_file_offset();
2071 // Reset special output object address and file offsets.
2072 for (Data_list::iterator p
= this->special_output_list_
.begin();
2073 p
!= this->special_output_list_
.end();
2075 (*p
)->reset_address_and_file_offset();
2077 // A linker script may have created some output section data objects.
2078 // They are useless now.
2079 for (Output_section_data_list::const_iterator p
=
2080 this->script_output_section_data_list_
.begin();
2081 p
!= this->script_output_section_data_list_
.end();
2084 this->script_output_section_data_list_
.clear();
2087 // Prepare for relaxation.
2090 Layout::prepare_for_relaxation()
2092 // Create an relaxation debug check if in debugging mode.
2093 if (is_debugging_enabled(DEBUG_RELAXATION
))
2094 this->relaxation_debug_check_
= new Relaxation_debug_check();
2096 // Save segment states.
2097 this->segment_states_
= new Segment_states();
2098 this->save_segments(this->segment_states_
);
2100 for(Section_list::const_iterator p
= this->section_list_
.begin();
2101 p
!= this->section_list_
.end();
2103 (*p
)->save_states();
2105 if (is_debugging_enabled(DEBUG_RELAXATION
))
2106 this->relaxation_debug_check_
->check_output_data_for_reset_values(
2107 this->section_list_
, this->special_output_list_
);
2109 // Also enable recording of output section data from scripts.
2110 this->record_output_section_data_from_script_
= true;
2113 // Relaxation loop body: If target has no relaxation, this runs only once
2114 // Otherwise, the target relaxation hook is called at the end of
2115 // each iteration. If the hook returns true, it means re-layout of
2116 // section is required.
2118 // The number of segments created by a linking script without a PHDRS
2119 // clause may be affected by section sizes and alignments. There is
2120 // a remote chance that relaxation causes different number of PT_LOAD
2121 // segments are created and sections are attached to different segments.
2122 // Therefore, we always throw away all segments created during section
2123 // layout. In order to be able to restart the section layout, we keep
2124 // a copy of the segment list right before the relaxation loop and use
2125 // that to restore the segments.
2127 // PASS is the current relaxation pass number.
2128 // SYMTAB is a symbol table.
2129 // PLOAD_SEG is the address of a pointer for the load segment.
2130 // PHDR_SEG is a pointer to the PHDR segment.
2131 // SEGMENT_HEADERS points to the output segment header.
2132 // FILE_HEADER points to the output file header.
2133 // PSHNDX is the address to store the output section index.
2136 Layout::relaxation_loop_body(
2139 Symbol_table
* symtab
,
2140 Output_segment
** pload_seg
,
2141 Output_segment
* phdr_seg
,
2142 Output_segment_headers
* segment_headers
,
2143 Output_file_header
* file_header
,
2144 unsigned int* pshndx
)
2146 // If this is not the first iteration, we need to clean up after
2147 // relaxation so that we can lay out the sections again.
2149 this->clean_up_after_relaxation();
2151 // If there is a SECTIONS clause, put all the input sections into
2152 // the required order.
2153 Output_segment
* load_seg
;
2154 if (this->script_options_
->saw_sections_clause())
2155 load_seg
= this->set_section_addresses_from_script(symtab
);
2156 else if (parameters
->options().relocatable())
2159 load_seg
= this->find_first_load_seg(target
);
2161 if (parameters
->options().oformat_enum()
2162 != General_options::OBJECT_FORMAT_ELF
)
2165 // If the user set the address of the text segment, that may not be
2166 // compatible with putting the segment headers and file headers into
2168 if (parameters
->options().user_set_Ttext()
2169 && parameters
->options().Ttext() % target
->common_pagesize() != 0)
2175 gold_assert(phdr_seg
== NULL
2177 || this->script_options_
->saw_sections_clause());
2179 // If the address of the load segment we found has been set by
2180 // --section-start rather than by a script, then adjust the VMA and
2181 // LMA downward if possible to include the file and section headers.
2182 uint64_t header_gap
= 0;
2183 if (load_seg
!= NULL
2184 && load_seg
->are_addresses_set()
2185 && !this->script_options_
->saw_sections_clause()
2186 && !parameters
->options().relocatable())
2188 file_header
->finalize_data_size();
2189 segment_headers
->finalize_data_size();
2190 size_t sizeof_headers
= (file_header
->data_size()
2191 + segment_headers
->data_size());
2192 const uint64_t abi_pagesize
= target
->abi_pagesize();
2193 uint64_t hdr_paddr
= load_seg
->paddr() - sizeof_headers
;
2194 hdr_paddr
&= ~(abi_pagesize
- 1);
2195 uint64_t subtract
= load_seg
->paddr() - hdr_paddr
;
2196 if (load_seg
->paddr() < subtract
|| load_seg
->vaddr() < subtract
)
2200 load_seg
->set_addresses(load_seg
->vaddr() - subtract
,
2201 load_seg
->paddr() - subtract
);
2202 header_gap
= subtract
- sizeof_headers
;
2206 // Lay out the segment headers.
2207 if (!parameters
->options().relocatable())
2209 gold_assert(segment_headers
!= NULL
);
2210 if (header_gap
!= 0 && load_seg
!= NULL
)
2212 Output_data_zero_fill
* z
= new Output_data_zero_fill(header_gap
, 1);
2213 load_seg
->add_initial_output_data(z
);
2215 if (load_seg
!= NULL
)
2216 load_seg
->add_initial_output_data(segment_headers
);
2217 if (phdr_seg
!= NULL
)
2218 phdr_seg
->add_initial_output_data(segment_headers
);
2221 // Lay out the file header.
2222 if (load_seg
!= NULL
)
2223 load_seg
->add_initial_output_data(file_header
);
2225 if (this->script_options_
->saw_phdrs_clause()
2226 && !parameters
->options().relocatable())
2228 // Support use of FILEHDRS and PHDRS attachments in a PHDRS
2229 // clause in a linker script.
2230 Script_sections
* ss
= this->script_options_
->script_sections();
2231 ss
->put_headers_in_phdrs(file_header
, segment_headers
);
2234 // We set the output section indexes in set_segment_offsets and
2235 // set_section_indexes.
2238 // Set the file offsets of all the segments, and all the sections
2241 if (!parameters
->options().relocatable())
2242 off
= this->set_segment_offsets(target
, load_seg
, pshndx
);
2244 off
= this->set_relocatable_section_offsets(file_header
, pshndx
);
2246 // Verify that the dummy relaxation does not change anything.
2247 if (is_debugging_enabled(DEBUG_RELAXATION
))
2250 this->relaxation_debug_check_
->read_sections(this->section_list_
);
2252 this->relaxation_debug_check_
->verify_sections(this->section_list_
);
2255 *pload_seg
= load_seg
;
2259 // Search the list of patterns and find the postion of the given section
2260 // name in the output section. If the section name matches a glob
2261 // pattern and a non-glob name, then the non-glob position takes
2262 // precedence. Return 0 if no match is found.
2265 Layout::find_section_order_index(const std::string
& section_name
)
2267 Unordered_map
<std::string
, unsigned int>::iterator map_it
;
2268 map_it
= this->input_section_position_
.find(section_name
);
2269 if (map_it
!= this->input_section_position_
.end())
2270 return map_it
->second
;
2272 // Absolute match failed. Linear search the glob patterns.
2273 std::vector
<std::string
>::iterator it
;
2274 for (it
= this->input_section_glob_
.begin();
2275 it
!= this->input_section_glob_
.end();
2278 if (fnmatch((*it
).c_str(), section_name
.c_str(), FNM_NOESCAPE
) == 0)
2280 map_it
= this->input_section_position_
.find(*it
);
2281 gold_assert(map_it
!= this->input_section_position_
.end());
2282 return map_it
->second
;
2288 // Read the sequence of input sections from the file specified with
2289 // option --section-ordering-file.
2292 Layout::read_layout_from_file()
2294 const char* filename
= parameters
->options().section_ordering_file();
2300 gold_fatal(_("unable to open --section-ordering-file file %s: %s"),
2301 filename
, strerror(errno
));
2303 std::getline(in
, line
); // this chops off the trailing \n, if any
2304 unsigned int position
= 1;
2305 this->set_section_ordering_specified();
2309 if (!line
.empty() && line
[line
.length() - 1] == '\r') // Windows
2310 line
.resize(line
.length() - 1);
2311 // Ignore comments, beginning with '#'
2314 std::getline(in
, line
);
2317 this->input_section_position_
[line
] = position
;
2318 // Store all glob patterns in a vector.
2319 if (is_wildcard_string(line
.c_str()))
2320 this->input_section_glob_
.push_back(line
);
2322 std::getline(in
, line
);
2326 // Finalize the layout. When this is called, we have created all the
2327 // output sections and all the output segments which are based on
2328 // input sections. We have several things to do, and we have to do
2329 // them in the right order, so that we get the right results correctly
2332 // 1) Finalize the list of output segments and create the segment
2335 // 2) Finalize the dynamic symbol table and associated sections.
2337 // 3) Determine the final file offset of all the output segments.
2339 // 4) Determine the final file offset of all the SHF_ALLOC output
2342 // 5) Create the symbol table sections and the section name table
2345 // 6) Finalize the symbol table: set symbol values to their final
2346 // value and make a final determination of which symbols are going
2347 // into the output symbol table.
2349 // 7) Create the section table header.
2351 // 8) Determine the final file offset of all the output sections which
2352 // are not SHF_ALLOC, including the section table header.
2354 // 9) Finalize the ELF file header.
2356 // This function returns the size of the output file.
2359 Layout::finalize(const Input_objects
* input_objects
, Symbol_table
* symtab
,
2360 Target
* target
, const Task
* task
)
2362 target
->finalize_sections(this, input_objects
, symtab
);
2364 this->count_local_symbols(task
, input_objects
);
2366 this->link_stabs_sections();
2368 Output_segment
* phdr_seg
= NULL
;
2369 if (!parameters
->options().relocatable() && !parameters
->doing_static_link())
2371 // There was a dynamic object in the link. We need to create
2372 // some information for the dynamic linker.
2374 // Create the PT_PHDR segment which will hold the program
2376 if (!this->script_options_
->saw_phdrs_clause())
2377 phdr_seg
= this->make_output_segment(elfcpp::PT_PHDR
, elfcpp::PF_R
);
2379 // Create the dynamic symbol table, including the hash table.
2380 Output_section
* dynstr
;
2381 std::vector
<Symbol
*> dynamic_symbols
;
2382 unsigned int local_dynamic_count
;
2383 Versions
versions(*this->script_options()->version_script_info(),
2385 this->create_dynamic_symtab(input_objects
, symtab
, &dynstr
,
2386 &local_dynamic_count
, &dynamic_symbols
,
2389 // Create the .interp section to hold the name of the
2390 // interpreter, and put it in a PT_INTERP segment. Don't do it
2391 // if we saw a .interp section in an input file.
2392 if ((!parameters
->options().shared()
2393 || parameters
->options().dynamic_linker() != NULL
)
2394 && this->interp_segment_
== NULL
)
2395 this->create_interp(target
);
2397 // Finish the .dynamic section to hold the dynamic data, and put
2398 // it in a PT_DYNAMIC segment.
2399 this->finish_dynamic_section(input_objects
, symtab
);
2401 // We should have added everything we need to the dynamic string
2403 this->dynpool_
.set_string_offsets();
2405 // Create the version sections. We can't do this until the
2406 // dynamic string table is complete.
2407 this->create_version_sections(&versions
, symtab
, local_dynamic_count
,
2408 dynamic_symbols
, dynstr
);
2410 // Set the size of the _DYNAMIC symbol. We can't do this until
2411 // after we call create_version_sections.
2412 this->set_dynamic_symbol_size(symtab
);
2415 // Create segment headers.
2416 Output_segment_headers
* segment_headers
=
2417 (parameters
->options().relocatable()
2419 : new Output_segment_headers(this->segment_list_
));
2421 // Lay out the file header.
2422 Output_file_header
* file_header
= new Output_file_header(target
, symtab
,
2425 this->special_output_list_
.push_back(file_header
);
2426 if (segment_headers
!= NULL
)
2427 this->special_output_list_
.push_back(segment_headers
);
2429 // Find approriate places for orphan output sections if we are using
2431 if (this->script_options_
->saw_sections_clause())
2432 this->place_orphan_sections_in_script();
2434 Output_segment
* load_seg
;
2439 // Take a snapshot of the section layout as needed.
2440 if (target
->may_relax())
2441 this->prepare_for_relaxation();
2443 // Run the relaxation loop to lay out sections.
2446 off
= this->relaxation_loop_body(pass
, target
, symtab
, &load_seg
,
2447 phdr_seg
, segment_headers
, file_header
,
2451 while (target
->may_relax()
2452 && target
->relax(pass
, input_objects
, symtab
, this, task
));
2454 // Set the file offsets of all the non-data sections we've seen so
2455 // far which don't have to wait for the input sections. We need
2456 // this in order to finalize local symbols in non-allocated
2458 off
= this->set_section_offsets(off
, BEFORE_INPUT_SECTIONS_PASS
);
2460 // Set the section indexes of all unallocated sections seen so far,
2461 // in case any of them are somehow referenced by a symbol.
2462 shndx
= this->set_section_indexes(shndx
);
2464 // Create the symbol table sections.
2465 this->create_symtab_sections(input_objects
, symtab
, shndx
, &off
);
2466 if (!parameters
->doing_static_link())
2467 this->assign_local_dynsym_offsets(input_objects
);
2469 // Process any symbol assignments from a linker script. This must
2470 // be called after the symbol table has been finalized.
2471 this->script_options_
->finalize_symbols(symtab
, this);
2473 // Create the incremental inputs sections.
2474 if (this->incremental_inputs_
)
2476 this->incremental_inputs_
->finalize();
2477 this->create_incremental_info_sections(symtab
);
2480 // Create the .shstrtab section.
2481 Output_section
* shstrtab_section
= this->create_shstrtab();
2483 // Set the file offsets of the rest of the non-data sections which
2484 // don't have to wait for the input sections.
2485 off
= this->set_section_offsets(off
, BEFORE_INPUT_SECTIONS_PASS
);
2487 // Now that all sections have been created, set the section indexes
2488 // for any sections which haven't been done yet.
2489 shndx
= this->set_section_indexes(shndx
);
2491 // Create the section table header.
2492 this->create_shdrs(shstrtab_section
, &off
);
2494 // If there are no sections which require postprocessing, we can
2495 // handle the section names now, and avoid a resize later.
2496 if (!this->any_postprocessing_sections_
)
2498 off
= this->set_section_offsets(off
,
2499 POSTPROCESSING_SECTIONS_PASS
);
2501 this->set_section_offsets(off
,
2502 STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
);
2505 file_header
->set_section_info(this->section_headers_
, shstrtab_section
);
2507 // Now we know exactly where everything goes in the output file
2508 // (except for non-allocated sections which require postprocessing).
2509 Output_data::layout_complete();
2511 this->output_file_size_
= off
;
2516 // Create a note header following the format defined in the ELF ABI.
2517 // NAME is the name, NOTE_TYPE is the type, SECTION_NAME is the name
2518 // of the section to create, DESCSZ is the size of the descriptor.
2519 // ALLOCATE is true if the section should be allocated in memory.
2520 // This returns the new note section. It sets *TRAILING_PADDING to
2521 // the number of trailing zero bytes required.
2524 Layout::create_note(const char* name
, int note_type
,
2525 const char* section_name
, size_t descsz
,
2526 bool allocate
, size_t* trailing_padding
)
2528 // Authorities all agree that the values in a .note field should
2529 // be aligned on 4-byte boundaries for 32-bit binaries. However,
2530 // they differ on what the alignment is for 64-bit binaries.
2531 // The GABI says unambiguously they take 8-byte alignment:
2532 // http://sco.com/developers/gabi/latest/ch5.pheader.html#note_section
2533 // Other documentation says alignment should always be 4 bytes:
2534 // http://www.netbsd.org/docs/kernel/elf-notes.html#note-format
2535 // GNU ld and GNU readelf both support the latter (at least as of
2536 // version 2.16.91), and glibc always generates the latter for
2537 // .note.ABI-tag (as of version 1.6), so that's the one we go with
2539 #ifdef GABI_FORMAT_FOR_DOTNOTE_SECTION // This is not defined by default.
2540 const int size
= parameters
->target().get_size();
2542 const int size
= 32;
2545 // The contents of the .note section.
2546 size_t namesz
= strlen(name
) + 1;
2547 size_t aligned_namesz
= align_address(namesz
, size
/ 8);
2548 size_t aligned_descsz
= align_address(descsz
, size
/ 8);
2550 size_t notehdrsz
= 3 * (size
/ 8) + aligned_namesz
;
2552 unsigned char* buffer
= new unsigned char[notehdrsz
];
2553 memset(buffer
, 0, notehdrsz
);
2555 bool is_big_endian
= parameters
->target().is_big_endian();
2561 elfcpp::Swap
<32, false>::writeval(buffer
, namesz
);
2562 elfcpp::Swap
<32, false>::writeval(buffer
+ 4, descsz
);
2563 elfcpp::Swap
<32, false>::writeval(buffer
+ 8, note_type
);
2567 elfcpp::Swap
<32, true>::writeval(buffer
, namesz
);
2568 elfcpp::Swap
<32, true>::writeval(buffer
+ 4, descsz
);
2569 elfcpp::Swap
<32, true>::writeval(buffer
+ 8, note_type
);
2572 else if (size
== 64)
2576 elfcpp::Swap
<64, false>::writeval(buffer
, namesz
);
2577 elfcpp::Swap
<64, false>::writeval(buffer
+ 8, descsz
);
2578 elfcpp::Swap
<64, false>::writeval(buffer
+ 16, note_type
);
2582 elfcpp::Swap
<64, true>::writeval(buffer
, namesz
);
2583 elfcpp::Swap
<64, true>::writeval(buffer
+ 8, descsz
);
2584 elfcpp::Swap
<64, true>::writeval(buffer
+ 16, note_type
);
2590 memcpy(buffer
+ 3 * (size
/ 8), name
, namesz
);
2592 elfcpp::Elf_Xword flags
= 0;
2593 Output_section_order order
= ORDER_INVALID
;
2596 flags
= elfcpp::SHF_ALLOC
;
2597 order
= ORDER_RO_NOTE
;
2599 Output_section
* os
= this->choose_output_section(NULL
, section_name
,
2601 flags
, false, order
, false);
2605 Output_section_data
* posd
= new Output_data_const_buffer(buffer
, notehdrsz
,
2608 os
->add_output_section_data(posd
);
2610 *trailing_padding
= aligned_descsz
- descsz
;
2615 // For an executable or shared library, create a note to record the
2616 // version of gold used to create the binary.
2619 Layout::create_gold_note()
2621 if (parameters
->options().relocatable()
2622 || parameters
->incremental_update())
2625 std::string desc
= std::string("gold ") + gold::get_version_string();
2627 size_t trailing_padding
;
2628 Output_section
* os
= this->create_note("GNU", elfcpp::NT_GNU_GOLD_VERSION
,
2629 ".note.gnu.gold-version", desc
.size(),
2630 false, &trailing_padding
);
2634 Output_section_data
* posd
= new Output_data_const(desc
, 4);
2635 os
->add_output_section_data(posd
);
2637 if (trailing_padding
> 0)
2639 posd
= new Output_data_zero_fill(trailing_padding
, 0);
2640 os
->add_output_section_data(posd
);
2644 // Record whether the stack should be executable. This can be set
2645 // from the command line using the -z execstack or -z noexecstack
2646 // options. Otherwise, if any input file has a .note.GNU-stack
2647 // section with the SHF_EXECINSTR flag set, the stack should be
2648 // executable. Otherwise, if at least one input file a
2649 // .note.GNU-stack section, and some input file has no .note.GNU-stack
2650 // section, we use the target default for whether the stack should be
2651 // executable. Otherwise, we don't generate a stack note. When
2652 // generating a object file, we create a .note.GNU-stack section with
2653 // the appropriate marking. When generating an executable or shared
2654 // library, we create a PT_GNU_STACK segment.
2657 Layout::create_executable_stack_info()
2659 bool is_stack_executable
;
2660 if (parameters
->options().is_execstack_set())
2661 is_stack_executable
= parameters
->options().is_stack_executable();
2662 else if (!this->input_with_gnu_stack_note_
)
2666 if (this->input_requires_executable_stack_
)
2667 is_stack_executable
= true;
2668 else if (this->input_without_gnu_stack_note_
)
2669 is_stack_executable
=
2670 parameters
->target().is_default_stack_executable();
2672 is_stack_executable
= false;
2675 if (parameters
->options().relocatable())
2677 const char* name
= this->namepool_
.add(".note.GNU-stack", false, NULL
);
2678 elfcpp::Elf_Xword flags
= 0;
2679 if (is_stack_executable
)
2680 flags
|= elfcpp::SHF_EXECINSTR
;
2681 this->make_output_section(name
, elfcpp::SHT_PROGBITS
, flags
,
2682 ORDER_INVALID
, false);
2686 if (this->script_options_
->saw_phdrs_clause())
2688 int flags
= elfcpp::PF_R
| elfcpp::PF_W
;
2689 if (is_stack_executable
)
2690 flags
|= elfcpp::PF_X
;
2691 this->make_output_segment(elfcpp::PT_GNU_STACK
, flags
);
2695 // If --build-id was used, set up the build ID note.
2698 Layout::create_build_id()
2700 if (!parameters
->options().user_set_build_id())
2703 const char* style
= parameters
->options().build_id();
2704 if (strcmp(style
, "none") == 0)
2707 // Set DESCSZ to the size of the note descriptor. When possible,
2708 // set DESC to the note descriptor contents.
2711 if (strcmp(style
, "md5") == 0)
2713 else if (strcmp(style
, "sha1") == 0)
2715 else if (strcmp(style
, "uuid") == 0)
2717 const size_t uuidsz
= 128 / 8;
2719 char buffer
[uuidsz
];
2720 memset(buffer
, 0, uuidsz
);
2722 int descriptor
= open_descriptor(-1, "/dev/urandom", O_RDONLY
);
2724 gold_error(_("--build-id=uuid failed: could not open /dev/urandom: %s"),
2728 ssize_t got
= ::read(descriptor
, buffer
, uuidsz
);
2729 release_descriptor(descriptor
, true);
2731 gold_error(_("/dev/urandom: read failed: %s"), strerror(errno
));
2732 else if (static_cast<size_t>(got
) != uuidsz
)
2733 gold_error(_("/dev/urandom: expected %zu bytes, got %zd bytes"),
2737 desc
.assign(buffer
, uuidsz
);
2740 else if (strncmp(style
, "0x", 2) == 0)
2743 const char* p
= style
+ 2;
2746 if (hex_p(p
[0]) && hex_p(p
[1]))
2748 char c
= (hex_value(p
[0]) << 4) | hex_value(p
[1]);
2752 else if (*p
== '-' || *p
== ':')
2755 gold_fatal(_("--build-id argument '%s' not a valid hex number"),
2758 descsz
= desc
.size();
2761 gold_fatal(_("unrecognized --build-id argument '%s'"), style
);
2764 size_t trailing_padding
;
2765 Output_section
* os
= this->create_note("GNU", elfcpp::NT_GNU_BUILD_ID
,
2766 ".note.gnu.build-id", descsz
, true,
2773 // We know the value already, so we fill it in now.
2774 gold_assert(desc
.size() == descsz
);
2776 Output_section_data
* posd
= new Output_data_const(desc
, 4);
2777 os
->add_output_section_data(posd
);
2779 if (trailing_padding
!= 0)
2781 posd
= new Output_data_zero_fill(trailing_padding
, 0);
2782 os
->add_output_section_data(posd
);
2787 // We need to compute a checksum after we have completed the
2789 gold_assert(trailing_padding
== 0);
2790 this->build_id_note_
= new Output_data_zero_fill(descsz
, 4);
2791 os
->add_output_section_data(this->build_id_note_
);
2795 // If we have both .stabXX and .stabXXstr sections, then the sh_link
2796 // field of the former should point to the latter. I'm not sure who
2797 // started this, but the GNU linker does it, and some tools depend
2801 Layout::link_stabs_sections()
2803 if (!this->have_stabstr_section_
)
2806 for (Section_list::iterator p
= this->section_list_
.begin();
2807 p
!= this->section_list_
.end();
2810 if ((*p
)->type() != elfcpp::SHT_STRTAB
)
2813 const char* name
= (*p
)->name();
2814 if (strncmp(name
, ".stab", 5) != 0)
2817 size_t len
= strlen(name
);
2818 if (strcmp(name
+ len
- 3, "str") != 0)
2821 std::string
stab_name(name
, len
- 3);
2822 Output_section
* stab_sec
;
2823 stab_sec
= this->find_output_section(stab_name
.c_str());
2824 if (stab_sec
!= NULL
)
2825 stab_sec
->set_link_section(*p
);
2829 // Create .gnu_incremental_inputs and related sections needed
2830 // for the next run of incremental linking to check what has changed.
2833 Layout::create_incremental_info_sections(Symbol_table
* symtab
)
2835 Incremental_inputs
* incr
= this->incremental_inputs_
;
2837 gold_assert(incr
!= NULL
);
2839 // Create the .gnu_incremental_inputs, _symtab, and _relocs input sections.
2840 incr
->create_data_sections(symtab
);
2842 // Add the .gnu_incremental_inputs section.
2843 const char* incremental_inputs_name
=
2844 this->namepool_
.add(".gnu_incremental_inputs", false, NULL
);
2845 Output_section
* incremental_inputs_os
=
2846 this->make_output_section(incremental_inputs_name
,
2847 elfcpp::SHT_GNU_INCREMENTAL_INPUTS
, 0,
2848 ORDER_INVALID
, false);
2849 incremental_inputs_os
->add_output_section_data(incr
->inputs_section());
2851 // Add the .gnu_incremental_symtab section.
2852 const char* incremental_symtab_name
=
2853 this->namepool_
.add(".gnu_incremental_symtab", false, NULL
);
2854 Output_section
* incremental_symtab_os
=
2855 this->make_output_section(incremental_symtab_name
,
2856 elfcpp::SHT_GNU_INCREMENTAL_SYMTAB
, 0,
2857 ORDER_INVALID
, false);
2858 incremental_symtab_os
->add_output_section_data(incr
->symtab_section());
2859 incremental_symtab_os
->set_entsize(4);
2861 // Add the .gnu_incremental_relocs section.
2862 const char* incremental_relocs_name
=
2863 this->namepool_
.add(".gnu_incremental_relocs", false, NULL
);
2864 Output_section
* incremental_relocs_os
=
2865 this->make_output_section(incremental_relocs_name
,
2866 elfcpp::SHT_GNU_INCREMENTAL_RELOCS
, 0,
2867 ORDER_INVALID
, false);
2868 incremental_relocs_os
->add_output_section_data(incr
->relocs_section());
2869 incremental_relocs_os
->set_entsize(incr
->relocs_entsize());
2871 // Add the .gnu_incremental_got_plt section.
2872 const char* incremental_got_plt_name
=
2873 this->namepool_
.add(".gnu_incremental_got_plt", false, NULL
);
2874 Output_section
* incremental_got_plt_os
=
2875 this->make_output_section(incremental_got_plt_name
,
2876 elfcpp::SHT_GNU_INCREMENTAL_GOT_PLT
, 0,
2877 ORDER_INVALID
, false);
2878 incremental_got_plt_os
->add_output_section_data(incr
->got_plt_section());
2880 // Add the .gnu_incremental_strtab section.
2881 const char* incremental_strtab_name
=
2882 this->namepool_
.add(".gnu_incremental_strtab", false, NULL
);
2883 Output_section
* incremental_strtab_os
= this->make_output_section(incremental_strtab_name
,
2884 elfcpp::SHT_STRTAB
, 0,
2885 ORDER_INVALID
, false);
2886 Output_data_strtab
* strtab_data
=
2887 new Output_data_strtab(incr
->get_stringpool());
2888 incremental_strtab_os
->add_output_section_data(strtab_data
);
2890 incremental_inputs_os
->set_after_input_sections();
2891 incremental_symtab_os
->set_after_input_sections();
2892 incremental_relocs_os
->set_after_input_sections();
2893 incremental_got_plt_os
->set_after_input_sections();
2895 incremental_inputs_os
->set_link_section(incremental_strtab_os
);
2896 incremental_symtab_os
->set_link_section(incremental_inputs_os
);
2897 incremental_relocs_os
->set_link_section(incremental_inputs_os
);
2898 incremental_got_plt_os
->set_link_section(incremental_inputs_os
);
2901 // Return whether SEG1 should be before SEG2 in the output file. This
2902 // is based entirely on the segment type and flags. When this is
2903 // called the segment addresses have normally not yet been set.
2906 Layout::segment_precedes(const Output_segment
* seg1
,
2907 const Output_segment
* seg2
)
2909 elfcpp::Elf_Word type1
= seg1
->type();
2910 elfcpp::Elf_Word type2
= seg2
->type();
2912 // The single PT_PHDR segment is required to precede any loadable
2913 // segment. We simply make it always first.
2914 if (type1
== elfcpp::PT_PHDR
)
2916 gold_assert(type2
!= elfcpp::PT_PHDR
);
2919 if (type2
== elfcpp::PT_PHDR
)
2922 // The single PT_INTERP segment is required to precede any loadable
2923 // segment. We simply make it always second.
2924 if (type1
== elfcpp::PT_INTERP
)
2926 gold_assert(type2
!= elfcpp::PT_INTERP
);
2929 if (type2
== elfcpp::PT_INTERP
)
2932 // We then put PT_LOAD segments before any other segments.
2933 if (type1
== elfcpp::PT_LOAD
&& type2
!= elfcpp::PT_LOAD
)
2935 if (type2
== elfcpp::PT_LOAD
&& type1
!= elfcpp::PT_LOAD
)
2938 // We put the PT_TLS segment last except for the PT_GNU_RELRO
2939 // segment, because that is where the dynamic linker expects to find
2940 // it (this is just for efficiency; other positions would also work
2942 if (type1
== elfcpp::PT_TLS
2943 && type2
!= elfcpp::PT_TLS
2944 && type2
!= elfcpp::PT_GNU_RELRO
)
2946 if (type2
== elfcpp::PT_TLS
2947 && type1
!= elfcpp::PT_TLS
2948 && type1
!= elfcpp::PT_GNU_RELRO
)
2951 // We put the PT_GNU_RELRO segment last, because that is where the
2952 // dynamic linker expects to find it (as with PT_TLS, this is just
2954 if (type1
== elfcpp::PT_GNU_RELRO
&& type2
!= elfcpp::PT_GNU_RELRO
)
2956 if (type2
== elfcpp::PT_GNU_RELRO
&& type1
!= elfcpp::PT_GNU_RELRO
)
2959 const elfcpp::Elf_Word flags1
= seg1
->flags();
2960 const elfcpp::Elf_Word flags2
= seg2
->flags();
2962 // The order of non-PT_LOAD segments is unimportant. We simply sort
2963 // by the numeric segment type and flags values. There should not
2964 // be more than one segment with the same type and flags.
2965 if (type1
!= elfcpp::PT_LOAD
)
2968 return type1
< type2
;
2969 gold_assert(flags1
!= flags2
);
2970 return flags1
< flags2
;
2973 // If the addresses are set already, sort by load address.
2974 if (seg1
->are_addresses_set())
2976 if (!seg2
->are_addresses_set())
2979 unsigned int section_count1
= seg1
->output_section_count();
2980 unsigned int section_count2
= seg2
->output_section_count();
2981 if (section_count1
== 0 && section_count2
> 0)
2983 if (section_count1
> 0 && section_count2
== 0)
2986 uint64_t paddr1
= (seg1
->are_addresses_set()
2988 : seg1
->first_section_load_address());
2989 uint64_t paddr2
= (seg2
->are_addresses_set()
2991 : seg2
->first_section_load_address());
2993 if (paddr1
!= paddr2
)
2994 return paddr1
< paddr2
;
2996 else if (seg2
->are_addresses_set())
2999 // A segment which holds large data comes after a segment which does
3000 // not hold large data.
3001 if (seg1
->is_large_data_segment())
3003 if (!seg2
->is_large_data_segment())
3006 else if (seg2
->is_large_data_segment())
3009 // Otherwise, we sort PT_LOAD segments based on the flags. Readonly
3010 // segments come before writable segments. Then writable segments
3011 // with data come before writable segments without data. Then
3012 // executable segments come before non-executable segments. Then
3013 // the unlikely case of a non-readable segment comes before the
3014 // normal case of a readable segment. If there are multiple
3015 // segments with the same type and flags, we require that the
3016 // address be set, and we sort by virtual address and then physical
3018 if ((flags1
& elfcpp::PF_W
) != (flags2
& elfcpp::PF_W
))
3019 return (flags1
& elfcpp::PF_W
) == 0;
3020 if ((flags1
& elfcpp::PF_W
) != 0
3021 && seg1
->has_any_data_sections() != seg2
->has_any_data_sections())
3022 return seg1
->has_any_data_sections();
3023 if ((flags1
& elfcpp::PF_X
) != (flags2
& elfcpp::PF_X
))
3024 return (flags1
& elfcpp::PF_X
) != 0;
3025 if ((flags1
& elfcpp::PF_R
) != (flags2
& elfcpp::PF_R
))
3026 return (flags1
& elfcpp::PF_R
) == 0;
3028 // We shouldn't get here--we shouldn't create segments which we
3029 // can't distinguish. Unless of course we are using a weird linker
3030 // script or overlapping --section-start options.
3031 gold_assert(this->script_options_
->saw_phdrs_clause()
3032 || parameters
->options().any_section_start());
3036 // Increase OFF so that it is congruent to ADDR modulo ABI_PAGESIZE.
3039 align_file_offset(off_t off
, uint64_t addr
, uint64_t abi_pagesize
)
3041 uint64_t unsigned_off
= off
;
3042 uint64_t aligned_off
= ((unsigned_off
& ~(abi_pagesize
- 1))
3043 | (addr
& (abi_pagesize
- 1)));
3044 if (aligned_off
< unsigned_off
)
3045 aligned_off
+= abi_pagesize
;
3049 // Set the file offsets of all the segments, and all the sections they
3050 // contain. They have all been created. LOAD_SEG must be be laid out
3051 // first. Return the offset of the data to follow.
3054 Layout::set_segment_offsets(const Target
* target
, Output_segment
* load_seg
,
3055 unsigned int* pshndx
)
3057 // Sort them into the final order. We use a stable sort so that we
3058 // don't randomize the order of indistinguishable segments created
3059 // by linker scripts.
3060 std::stable_sort(this->segment_list_
.begin(), this->segment_list_
.end(),
3061 Layout::Compare_segments(this));
3063 // Find the PT_LOAD segments, and set their addresses and offsets
3064 // and their section's addresses and offsets.
3065 uint64_t start_addr
;
3066 if (parameters
->options().user_set_Ttext())
3067 start_addr
= parameters
->options().Ttext();
3068 else if (parameters
->options().output_is_position_independent())
3071 start_addr
= target
->default_text_segment_address();
3073 uint64_t addr
= start_addr
;
3076 // If LOAD_SEG is NULL, then the file header and segment headers
3077 // will not be loadable. But they still need to be at offset 0 in
3078 // the file. Set their offsets now.
3079 if (load_seg
== NULL
)
3081 for (Data_list::iterator p
= this->special_output_list_
.begin();
3082 p
!= this->special_output_list_
.end();
3085 off
= align_address(off
, (*p
)->addralign());
3086 (*p
)->set_address_and_file_offset(0, off
);
3087 off
+= (*p
)->data_size();
3091 unsigned int increase_relro
= this->increase_relro_
;
3092 if (this->script_options_
->saw_sections_clause())
3095 const bool check_sections
= parameters
->options().check_sections();
3096 Output_segment
* last_load_segment
= NULL
;
3098 unsigned int shndx_begin
= *pshndx
;
3099 unsigned int shndx_load_seg
= *pshndx
;
3101 for (Segment_list::iterator p
= this->segment_list_
.begin();
3102 p
!= this->segment_list_
.end();
3105 if ((*p
)->type() == elfcpp::PT_LOAD
)
3107 if (target
->isolate_execinstr())
3109 // When we hit the segment that should contain the
3110 // file headers, reset the file offset so we place
3111 // it and subsequent segments appropriately.
3112 // We'll fix up the preceding segments below.
3120 shndx_load_seg
= *pshndx
;
3126 // Verify that the file headers fall into the first segment.
3127 if (load_seg
!= NULL
&& load_seg
!= *p
)
3132 bool are_addresses_set
= (*p
)->are_addresses_set();
3133 if (are_addresses_set
)
3135 // When it comes to setting file offsets, we care about
3136 // the physical address.
3137 addr
= (*p
)->paddr();
3139 else if (parameters
->options().user_set_Ttext()
3140 && ((*p
)->flags() & elfcpp::PF_W
) == 0)
3142 are_addresses_set
= true;
3144 else if (parameters
->options().user_set_Tdata()
3145 && ((*p
)->flags() & elfcpp::PF_W
) != 0
3146 && (!parameters
->options().user_set_Tbss()
3147 || (*p
)->has_any_data_sections()))
3149 addr
= parameters
->options().Tdata();
3150 are_addresses_set
= true;
3152 else if (parameters
->options().user_set_Tbss()
3153 && ((*p
)->flags() & elfcpp::PF_W
) != 0
3154 && !(*p
)->has_any_data_sections())
3156 addr
= parameters
->options().Tbss();
3157 are_addresses_set
= true;
3160 uint64_t orig_addr
= addr
;
3161 uint64_t orig_off
= off
;
3163 uint64_t aligned_addr
= 0;
3164 uint64_t abi_pagesize
= target
->abi_pagesize();
3165 uint64_t common_pagesize
= target
->common_pagesize();
3167 if (!parameters
->options().nmagic()
3168 && !parameters
->options().omagic())
3169 (*p
)->set_minimum_p_align(common_pagesize
);
3171 if (!are_addresses_set
)
3173 // Skip the address forward one page, maintaining the same
3174 // position within the page. This lets us store both segments
3175 // overlapping on a single page in the file, but the loader will
3176 // put them on different pages in memory. We will revisit this
3177 // decision once we know the size of the segment.
3179 addr
= align_address(addr
, (*p
)->maximum_alignment());
3180 aligned_addr
= addr
;
3184 // This is the segment that will contain the file
3185 // headers, so its offset will have to be exactly zero.
3186 gold_assert(orig_off
== 0);
3188 // If the target wants a fixed minimum distance from the
3189 // text segment to the read-only segment, move up now.
3190 uint64_t min_addr
= start_addr
+ target
->rosegment_gap();
3191 if (addr
< min_addr
)
3194 // But this is not the first segment! To make its
3195 // address congruent with its offset, that address better
3196 // be aligned to the ABI-mandated page size.
3197 addr
= align_address(addr
, abi_pagesize
);
3198 aligned_addr
= addr
;
3202 if ((addr
& (abi_pagesize
- 1)) != 0)
3203 addr
= addr
+ abi_pagesize
;
3205 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
3209 if (!parameters
->options().nmagic()
3210 && !parameters
->options().omagic())
3211 off
= align_file_offset(off
, addr
, abi_pagesize
);
3214 // This is -N or -n with a section script which prevents
3215 // us from using a load segment. We need to ensure that
3216 // the file offset is aligned to the alignment of the
3217 // segment. This is because the linker script
3218 // implicitly assumed a zero offset. If we don't align
3219 // here, then the alignment of the sections in the
3220 // linker script may not match the alignment of the
3221 // sections in the set_section_addresses call below,
3222 // causing an error about dot moving backward.
3223 off
= align_address(off
, (*p
)->maximum_alignment());
3226 unsigned int shndx_hold
= *pshndx
;
3227 bool has_relro
= false;
3228 uint64_t new_addr
= (*p
)->set_section_addresses(this, false, addr
,
3233 // Now that we know the size of this segment, we may be able
3234 // to save a page in memory, at the cost of wasting some
3235 // file space, by instead aligning to the start of a new
3236 // page. Here we use the real machine page size rather than
3237 // the ABI mandated page size. If the segment has been
3238 // aligned so that the relro data ends at a page boundary,
3239 // we do not try to realign it.
3241 if (!are_addresses_set
3243 && aligned_addr
!= addr
3244 && !parameters
->incremental())
3246 uint64_t first_off
= (common_pagesize
3248 & (common_pagesize
- 1)));
3249 uint64_t last_off
= new_addr
& (common_pagesize
- 1);
3252 && ((aligned_addr
& ~ (common_pagesize
- 1))
3253 != (new_addr
& ~ (common_pagesize
- 1)))
3254 && first_off
+ last_off
<= common_pagesize
)
3256 *pshndx
= shndx_hold
;
3257 addr
= align_address(aligned_addr
, common_pagesize
);
3258 addr
= align_address(addr
, (*p
)->maximum_alignment());
3259 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
3260 off
= align_file_offset(off
, addr
, abi_pagesize
);
3262 increase_relro
= this->increase_relro_
;
3263 if (this->script_options_
->saw_sections_clause())
3267 new_addr
= (*p
)->set_section_addresses(this, true, addr
,
3276 // Implement --check-sections. We know that the segments
3277 // are sorted by LMA.
3278 if (check_sections
&& last_load_segment
!= NULL
)
3280 gold_assert(last_load_segment
->paddr() <= (*p
)->paddr());
3281 if (last_load_segment
->paddr() + last_load_segment
->memsz()
3284 unsigned long long lb1
= last_load_segment
->paddr();
3285 unsigned long long le1
= lb1
+ last_load_segment
->memsz();
3286 unsigned long long lb2
= (*p
)->paddr();
3287 unsigned long long le2
= lb2
+ (*p
)->memsz();
3288 gold_error(_("load segment overlap [0x%llx -> 0x%llx] and "
3289 "[0x%llx -> 0x%llx]"),
3290 lb1
, le1
, lb2
, le2
);
3293 last_load_segment
= *p
;
3297 if (load_seg
!= NULL
&& target
->isolate_execinstr())
3299 // Process the early segments again, setting their file offsets
3300 // so they land after the segments starting at LOAD_SEG.
3301 off
= align_file_offset(off
, 0, target
->abi_pagesize());
3303 for (Segment_list::iterator p
= this->segment_list_
.begin();
3307 if ((*p
)->type() == elfcpp::PT_LOAD
)
3309 // We repeat the whole job of assigning addresses and
3310 // offsets, but we really only want to change the offsets and
3311 // must ensure that the addresses all come out the same as
3312 // they did the first time through.
3313 bool has_relro
= false;
3314 const uint64_t old_addr
= (*p
)->vaddr();
3315 const uint64_t old_end
= old_addr
+ (*p
)->memsz();
3316 uint64_t new_addr
= (*p
)->set_section_addresses(this, true,
3322 gold_assert(new_addr
== old_end
);
3326 gold_assert(shndx_begin
== shndx_load_seg
);
3329 // Handle the non-PT_LOAD segments, setting their offsets from their
3330 // section's offsets.
3331 for (Segment_list::iterator p
= this->segment_list_
.begin();
3332 p
!= this->segment_list_
.end();
3335 if ((*p
)->type() != elfcpp::PT_LOAD
)
3336 (*p
)->set_offset((*p
)->type() == elfcpp::PT_GNU_RELRO
3341 // Set the TLS offsets for each section in the PT_TLS segment.
3342 if (this->tls_segment_
!= NULL
)
3343 this->tls_segment_
->set_tls_offsets();
3348 // Set the offsets of all the allocated sections when doing a
3349 // relocatable link. This does the same jobs as set_segment_offsets,
3350 // only for a relocatable link.
3353 Layout::set_relocatable_section_offsets(Output_data
* file_header
,
3354 unsigned int* pshndx
)
3358 file_header
->set_address_and_file_offset(0, 0);
3359 off
+= file_header
->data_size();
3361 for (Section_list::iterator p
= this->section_list_
.begin();
3362 p
!= this->section_list_
.end();
3365 // We skip unallocated sections here, except that group sections
3366 // have to come first.
3367 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) == 0
3368 && (*p
)->type() != elfcpp::SHT_GROUP
)
3371 off
= align_address(off
, (*p
)->addralign());
3373 // The linker script might have set the address.
3374 if (!(*p
)->is_address_valid())
3375 (*p
)->set_address(0);
3376 (*p
)->set_file_offset(off
);
3377 (*p
)->finalize_data_size();
3378 off
+= (*p
)->data_size();
3380 (*p
)->set_out_shndx(*pshndx
);
3387 // Set the file offset of all the sections not associated with a
3391 Layout::set_section_offsets(off_t off
, Layout::Section_offset_pass pass
)
3393 off_t startoff
= off
;
3396 for (Section_list::iterator p
= this->unattached_section_list_
.begin();
3397 p
!= this->unattached_section_list_
.end();
3400 // The symtab section is handled in create_symtab_sections.
3401 if (*p
== this->symtab_section_
)
3404 // If we've already set the data size, don't set it again.
3405 if ((*p
)->is_offset_valid() && (*p
)->is_data_size_valid())
3408 if (pass
== BEFORE_INPUT_SECTIONS_PASS
3409 && (*p
)->requires_postprocessing())
3411 (*p
)->create_postprocessing_buffer();
3412 this->any_postprocessing_sections_
= true;
3415 if (pass
== BEFORE_INPUT_SECTIONS_PASS
3416 && (*p
)->after_input_sections())
3418 else if (pass
== POSTPROCESSING_SECTIONS_PASS
3419 && (!(*p
)->after_input_sections()
3420 || (*p
)->type() == elfcpp::SHT_STRTAB
))
3422 else if (pass
== STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
3423 && (!(*p
)->after_input_sections()
3424 || (*p
)->type() != elfcpp::SHT_STRTAB
))
3427 if (!parameters
->incremental_update())
3429 off
= align_address(off
, (*p
)->addralign());
3430 (*p
)->set_file_offset(off
);
3431 (*p
)->finalize_data_size();
3435 // Incremental update: allocate file space from free list.
3436 (*p
)->pre_finalize_data_size();
3437 off_t current_size
= (*p
)->current_data_size();
3438 off
= this->allocate(current_size
, (*p
)->addralign(), startoff
);
3441 if (is_debugging_enabled(DEBUG_INCREMENTAL
))
3442 this->free_list_
.dump();
3443 gold_assert((*p
)->output_section() != NULL
);
3444 gold_fallback(_("out of patch space for section %s; "
3445 "relink with --incremental-full"),
3446 (*p
)->output_section()->name());
3448 (*p
)->set_file_offset(off
);
3449 (*p
)->finalize_data_size();
3450 if ((*p
)->data_size() > current_size
)
3452 gold_assert((*p
)->output_section() != NULL
);
3453 gold_fallback(_("%s: section changed size; "
3454 "relink with --incremental-full"),
3455 (*p
)->output_section()->name());
3457 gold_debug(DEBUG_INCREMENTAL
,
3458 "set_section_offsets: %08lx %08lx %s",
3459 static_cast<long>(off
),
3460 static_cast<long>((*p
)->data_size()),
3461 ((*p
)->output_section() != NULL
3462 ? (*p
)->output_section()->name() : "(special)"));
3465 off
+= (*p
)->data_size();
3469 // At this point the name must be set.
3470 if (pass
!= STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
)
3471 this->namepool_
.add((*p
)->name(), false, NULL
);
3476 // Set the section indexes of all the sections not associated with a
3480 Layout::set_section_indexes(unsigned int shndx
)
3482 for (Section_list::iterator p
= this->unattached_section_list_
.begin();
3483 p
!= this->unattached_section_list_
.end();
3486 if (!(*p
)->has_out_shndx())
3488 (*p
)->set_out_shndx(shndx
);
3495 // Set the section addresses according to the linker script. This is
3496 // only called when we see a SECTIONS clause. This returns the
3497 // program segment which should hold the file header and segment
3498 // headers, if any. It will return NULL if they should not be in a
3502 Layout::set_section_addresses_from_script(Symbol_table
* symtab
)
3504 Script_sections
* ss
= this->script_options_
->script_sections();
3505 gold_assert(ss
->saw_sections_clause());
3506 return this->script_options_
->set_section_addresses(symtab
, this);
3509 // Place the orphan sections in the linker script.
3512 Layout::place_orphan_sections_in_script()
3514 Script_sections
* ss
= this->script_options_
->script_sections();
3515 gold_assert(ss
->saw_sections_clause());
3517 // Place each orphaned output section in the script.
3518 for (Section_list::iterator p
= this->section_list_
.begin();
3519 p
!= this->section_list_
.end();
3522 if (!(*p
)->found_in_sections_clause())
3523 ss
->place_orphan(*p
);
3527 // Count the local symbols in the regular symbol table and the dynamic
3528 // symbol table, and build the respective string pools.
3531 Layout::count_local_symbols(const Task
* task
,
3532 const Input_objects
* input_objects
)
3534 // First, figure out an upper bound on the number of symbols we'll
3535 // be inserting into each pool. This helps us create the pools with
3536 // the right size, to avoid unnecessary hashtable resizing.
3537 unsigned int symbol_count
= 0;
3538 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3539 p
!= input_objects
->relobj_end();
3541 symbol_count
+= (*p
)->local_symbol_count();
3543 // Go from "upper bound" to "estimate." We overcount for two
3544 // reasons: we double-count symbols that occur in more than one
3545 // object file, and we count symbols that are dropped from the
3546 // output. Add it all together and assume we overcount by 100%.
3549 // We assume all symbols will go into both the sympool and dynpool.
3550 this->sympool_
.reserve(symbol_count
);
3551 this->dynpool_
.reserve(symbol_count
);
3553 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3554 p
!= input_objects
->relobj_end();
3557 Task_lock_obj
<Object
> tlo(task
, *p
);
3558 (*p
)->count_local_symbols(&this->sympool_
, &this->dynpool_
);
3562 // Create the symbol table sections. Here we also set the final
3563 // values of the symbols. At this point all the loadable sections are
3564 // fully laid out. SHNUM is the number of sections so far.
3567 Layout::create_symtab_sections(const Input_objects
* input_objects
,
3568 Symbol_table
* symtab
,
3574 if (parameters
->target().get_size() == 32)
3576 symsize
= elfcpp::Elf_sizes
<32>::sym_size
;
3579 else if (parameters
->target().get_size() == 64)
3581 symsize
= elfcpp::Elf_sizes
<64>::sym_size
;
3587 // Compute file offsets relative to the start of the symtab section.
3590 // Save space for the dummy symbol at the start of the section. We
3591 // never bother to write this out--it will just be left as zero.
3593 unsigned int local_symbol_index
= 1;
3595 // Add STT_SECTION symbols for each Output section which needs one.
3596 for (Section_list::iterator p
= this->section_list_
.begin();
3597 p
!= this->section_list_
.end();
3600 if (!(*p
)->needs_symtab_index())
3601 (*p
)->set_symtab_index(-1U);
3604 (*p
)->set_symtab_index(local_symbol_index
);
3605 ++local_symbol_index
;
3610 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3611 p
!= input_objects
->relobj_end();
3614 unsigned int index
= (*p
)->finalize_local_symbols(local_symbol_index
,
3616 off
+= (index
- local_symbol_index
) * symsize
;
3617 local_symbol_index
= index
;
3620 unsigned int local_symcount
= local_symbol_index
;
3621 gold_assert(static_cast<off_t
>(local_symcount
* symsize
) == off
);
3624 size_t dyn_global_index
;
3626 if (this->dynsym_section_
== NULL
)
3629 dyn_global_index
= 0;
3634 dyn_global_index
= this->dynsym_section_
->info();
3635 off_t locsize
= dyn_global_index
* this->dynsym_section_
->entsize();
3636 dynoff
= this->dynsym_section_
->offset() + locsize
;
3637 dyncount
= (this->dynsym_section_
->data_size() - locsize
) / symsize
;
3638 gold_assert(static_cast<off_t
>(dyncount
* symsize
)
3639 == this->dynsym_section_
->data_size() - locsize
);
3642 off_t global_off
= off
;
3643 off
= symtab
->finalize(off
, dynoff
, dyn_global_index
, dyncount
,
3644 &this->sympool_
, &local_symcount
);
3646 if (!parameters
->options().strip_all())
3648 this->sympool_
.set_string_offsets();
3650 const char* symtab_name
= this->namepool_
.add(".symtab", false, NULL
);
3651 Output_section
* osymtab
= this->make_output_section(symtab_name
,
3655 this->symtab_section_
= osymtab
;
3657 Output_section_data
* pos
= new Output_data_fixed_space(off
, align
,
3659 osymtab
->add_output_section_data(pos
);
3661 // We generate a .symtab_shndx section if we have more than
3662 // SHN_LORESERVE sections. Technically it is possible that we
3663 // don't need one, because it is possible that there are no
3664 // symbols in any of sections with indexes larger than
3665 // SHN_LORESERVE. That is probably unusual, though, and it is
3666 // easier to always create one than to compute section indexes
3667 // twice (once here, once when writing out the symbols).
3668 if (shnum
>= elfcpp::SHN_LORESERVE
)
3670 const char* symtab_xindex_name
= this->namepool_
.add(".symtab_shndx",
3672 Output_section
* osymtab_xindex
=
3673 this->make_output_section(symtab_xindex_name
,
3674 elfcpp::SHT_SYMTAB_SHNDX
, 0,
3675 ORDER_INVALID
, false);
3677 size_t symcount
= off
/ symsize
;
3678 this->symtab_xindex_
= new Output_symtab_xindex(symcount
);
3680 osymtab_xindex
->add_output_section_data(this->symtab_xindex_
);
3682 osymtab_xindex
->set_link_section(osymtab
);
3683 osymtab_xindex
->set_addralign(4);
3684 osymtab_xindex
->set_entsize(4);
3686 osymtab_xindex
->set_after_input_sections();
3688 // This tells the driver code to wait until the symbol table
3689 // has written out before writing out the postprocessing
3690 // sections, including the .symtab_shndx section.
3691 this->any_postprocessing_sections_
= true;
3694 const char* strtab_name
= this->namepool_
.add(".strtab", false, NULL
);
3695 Output_section
* ostrtab
= this->make_output_section(strtab_name
,
3700 Output_section_data
* pstr
= new Output_data_strtab(&this->sympool_
);
3701 ostrtab
->add_output_section_data(pstr
);
3704 if (!parameters
->incremental_update())
3705 symtab_off
= align_address(*poff
, align
);
3708 symtab_off
= this->allocate(off
, align
, *poff
);
3710 gold_fallback(_("out of patch space for symbol table; "
3711 "relink with --incremental-full"));
3712 gold_debug(DEBUG_INCREMENTAL
,
3713 "create_symtab_sections: %08lx %08lx .symtab",
3714 static_cast<long>(symtab_off
),
3715 static_cast<long>(off
));
3718 symtab
->set_file_offset(symtab_off
+ global_off
);
3719 osymtab
->set_file_offset(symtab_off
);
3720 osymtab
->finalize_data_size();
3721 osymtab
->set_link_section(ostrtab
);
3722 osymtab
->set_info(local_symcount
);
3723 osymtab
->set_entsize(symsize
);
3725 if (symtab_off
+ off
> *poff
)
3726 *poff
= symtab_off
+ off
;
3730 // Create the .shstrtab section, which holds the names of the
3731 // sections. At the time this is called, we have created all the
3732 // output sections except .shstrtab itself.
3735 Layout::create_shstrtab()
3737 // FIXME: We don't need to create a .shstrtab section if we are
3738 // stripping everything.
3740 const char* name
= this->namepool_
.add(".shstrtab", false, NULL
);
3742 Output_section
* os
= this->make_output_section(name
, elfcpp::SHT_STRTAB
, 0,
3743 ORDER_INVALID
, false);
3745 if (strcmp(parameters
->options().compress_debug_sections(), "none") != 0)
3747 // We can't write out this section until we've set all the
3748 // section names, and we don't set the names of compressed
3749 // output sections until relocations are complete. FIXME: With
3750 // the current names we use, this is unnecessary.
3751 os
->set_after_input_sections();
3754 Output_section_data
* posd
= new Output_data_strtab(&this->namepool_
);
3755 os
->add_output_section_data(posd
);
3760 // Create the section headers. SIZE is 32 or 64. OFF is the file
3764 Layout::create_shdrs(const Output_section
* shstrtab_section
, off_t
* poff
)
3766 Output_section_headers
* oshdrs
;
3767 oshdrs
= new Output_section_headers(this,
3768 &this->segment_list_
,
3769 &this->section_list_
,
3770 &this->unattached_section_list_
,
3774 if (!parameters
->incremental_update())
3775 off
= align_address(*poff
, oshdrs
->addralign());
3778 oshdrs
->pre_finalize_data_size();
3779 off
= this->allocate(oshdrs
->data_size(), oshdrs
->addralign(), *poff
);
3781 gold_fallback(_("out of patch space for section header table; "
3782 "relink with --incremental-full"));
3783 gold_debug(DEBUG_INCREMENTAL
,
3784 "create_shdrs: %08lx %08lx (section header table)",
3785 static_cast<long>(off
),
3786 static_cast<long>(off
+ oshdrs
->data_size()));
3788 oshdrs
->set_address_and_file_offset(0, off
);
3789 off
+= oshdrs
->data_size();
3792 this->section_headers_
= oshdrs
;
3795 // Count the allocated sections.
3798 Layout::allocated_output_section_count() const
3800 size_t section_count
= 0;
3801 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
3802 p
!= this->segment_list_
.end();
3804 section_count
+= (*p
)->output_section_count();
3805 return section_count
;
3808 // Create the dynamic symbol table.
3811 Layout::create_dynamic_symtab(const Input_objects
* input_objects
,
3812 Symbol_table
* symtab
,
3813 Output_section
** pdynstr
,
3814 unsigned int* plocal_dynamic_count
,
3815 std::vector
<Symbol
*>* pdynamic_symbols
,
3816 Versions
* pversions
)
3818 // Count all the symbols in the dynamic symbol table, and set the
3819 // dynamic symbol indexes.
3821 // Skip symbol 0, which is always all zeroes.
3822 unsigned int index
= 1;
3824 // Add STT_SECTION symbols for each Output section which needs one.
3825 for (Section_list::iterator p
= this->section_list_
.begin();
3826 p
!= this->section_list_
.end();
3829 if (!(*p
)->needs_dynsym_index())
3830 (*p
)->set_dynsym_index(-1U);
3833 (*p
)->set_dynsym_index(index
);
3838 // Count the local symbols that need to go in the dynamic symbol table,
3839 // and set the dynamic symbol indexes.
3840 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3841 p
!= input_objects
->relobj_end();
3844 unsigned int new_index
= (*p
)->set_local_dynsym_indexes(index
);
3848 unsigned int local_symcount
= index
;
3849 *plocal_dynamic_count
= local_symcount
;
3851 index
= symtab
->set_dynsym_indexes(index
, pdynamic_symbols
,
3852 &this->dynpool_
, pversions
);
3856 const int size
= parameters
->target().get_size();
3859 symsize
= elfcpp::Elf_sizes
<32>::sym_size
;
3862 else if (size
== 64)
3864 symsize
= elfcpp::Elf_sizes
<64>::sym_size
;
3870 // Create the dynamic symbol table section.
3872 Output_section
* dynsym
= this->choose_output_section(NULL
, ".dynsym",
3876 ORDER_DYNAMIC_LINKER
,
3879 // Check for NULL as a linker script may discard .dynsym.
3882 Output_section_data
* odata
= new Output_data_fixed_space(index
* symsize
,
3885 dynsym
->add_output_section_data(odata
);
3887 dynsym
->set_info(local_symcount
);
3888 dynsym
->set_entsize(symsize
);
3889 dynsym
->set_addralign(align
);
3891 this->dynsym_section_
= dynsym
;
3894 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
3897 odyn
->add_section_address(elfcpp::DT_SYMTAB
, dynsym
);
3898 odyn
->add_constant(elfcpp::DT_SYMENT
, symsize
);
3901 // If there are more than SHN_LORESERVE allocated sections, we
3902 // create a .dynsym_shndx section. It is possible that we don't
3903 // need one, because it is possible that there are no dynamic
3904 // symbols in any of the sections with indexes larger than
3905 // SHN_LORESERVE. This is probably unusual, though, and at this
3906 // time we don't know the actual section indexes so it is
3907 // inconvenient to check.
3908 if (this->allocated_output_section_count() >= elfcpp::SHN_LORESERVE
)
3910 Output_section
* dynsym_xindex
=
3911 this->choose_output_section(NULL
, ".dynsym_shndx",
3912 elfcpp::SHT_SYMTAB_SHNDX
,
3914 false, ORDER_DYNAMIC_LINKER
, false);
3916 if (dynsym_xindex
!= NULL
)
3918 this->dynsym_xindex_
= new Output_symtab_xindex(index
);
3920 dynsym_xindex
->add_output_section_data(this->dynsym_xindex_
);
3922 dynsym_xindex
->set_link_section(dynsym
);
3923 dynsym_xindex
->set_addralign(4);
3924 dynsym_xindex
->set_entsize(4);
3926 dynsym_xindex
->set_after_input_sections();
3928 // This tells the driver code to wait until the symbol table
3929 // has written out before writing out the postprocessing
3930 // sections, including the .dynsym_shndx section.
3931 this->any_postprocessing_sections_
= true;
3935 // Create the dynamic string table section.
3937 Output_section
* dynstr
= this->choose_output_section(NULL
, ".dynstr",
3941 ORDER_DYNAMIC_LINKER
,
3946 Output_section_data
* strdata
= new Output_data_strtab(&this->dynpool_
);
3947 dynstr
->add_output_section_data(strdata
);
3950 dynsym
->set_link_section(dynstr
);
3951 if (this->dynamic_section_
!= NULL
)
3952 this->dynamic_section_
->set_link_section(dynstr
);
3956 odyn
->add_section_address(elfcpp::DT_STRTAB
, dynstr
);
3957 odyn
->add_section_size(elfcpp::DT_STRSZ
, dynstr
);
3963 // Create the hash tables.
3965 if (strcmp(parameters
->options().hash_style(), "sysv") == 0
3966 || strcmp(parameters
->options().hash_style(), "both") == 0)
3968 unsigned char* phash
;
3969 unsigned int hashlen
;
3970 Dynobj::create_elf_hash_table(*pdynamic_symbols
, local_symcount
,
3973 Output_section
* hashsec
=
3974 this->choose_output_section(NULL
, ".hash", elfcpp::SHT_HASH
,
3975 elfcpp::SHF_ALLOC
, false,
3976 ORDER_DYNAMIC_LINKER
, false);
3978 Output_section_data
* hashdata
= new Output_data_const_buffer(phash
,
3982 if (hashsec
!= NULL
&& hashdata
!= NULL
)
3983 hashsec
->add_output_section_data(hashdata
);
3985 if (hashsec
!= NULL
)
3988 hashsec
->set_link_section(dynsym
);
3989 hashsec
->set_entsize(4);
3993 odyn
->add_section_address(elfcpp::DT_HASH
, hashsec
);
3996 if (strcmp(parameters
->options().hash_style(), "gnu") == 0
3997 || strcmp(parameters
->options().hash_style(), "both") == 0)
3999 unsigned char* phash
;
4000 unsigned int hashlen
;
4001 Dynobj::create_gnu_hash_table(*pdynamic_symbols
, local_symcount
,
4004 Output_section
* hashsec
=
4005 this->choose_output_section(NULL
, ".gnu.hash", elfcpp::SHT_GNU_HASH
,
4006 elfcpp::SHF_ALLOC
, false,
4007 ORDER_DYNAMIC_LINKER
, false);
4009 Output_section_data
* hashdata
= new Output_data_const_buffer(phash
,
4013 if (hashsec
!= NULL
&& hashdata
!= NULL
)
4014 hashsec
->add_output_section_data(hashdata
);
4016 if (hashsec
!= NULL
)
4019 hashsec
->set_link_section(dynsym
);
4021 // For a 64-bit target, the entries in .gnu.hash do not have
4022 // a uniform size, so we only set the entry size for a
4024 if (parameters
->target().get_size() == 32)
4025 hashsec
->set_entsize(4);
4028 odyn
->add_section_address(elfcpp::DT_GNU_HASH
, hashsec
);
4033 // Assign offsets to each local portion of the dynamic symbol table.
4036 Layout::assign_local_dynsym_offsets(const Input_objects
* input_objects
)
4038 Output_section
* dynsym
= this->dynsym_section_
;
4042 off_t off
= dynsym
->offset();
4044 // Skip the dummy symbol at the start of the section.
4045 off
+= dynsym
->entsize();
4047 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
4048 p
!= input_objects
->relobj_end();
4051 unsigned int count
= (*p
)->set_local_dynsym_offset(off
);
4052 off
+= count
* dynsym
->entsize();
4056 // Create the version sections.
4059 Layout::create_version_sections(const Versions
* versions
,
4060 const Symbol_table
* symtab
,
4061 unsigned int local_symcount
,
4062 const std::vector
<Symbol
*>& dynamic_symbols
,
4063 const Output_section
* dynstr
)
4065 if (!versions
->any_defs() && !versions
->any_needs())
4068 switch (parameters
->size_and_endianness())
4070 #ifdef HAVE_TARGET_32_LITTLE
4071 case Parameters::TARGET_32_LITTLE
:
4072 this->sized_create_version_sections
<32, false>(versions
, symtab
,
4074 dynamic_symbols
, dynstr
);
4077 #ifdef HAVE_TARGET_32_BIG
4078 case Parameters::TARGET_32_BIG
:
4079 this->sized_create_version_sections
<32, true>(versions
, symtab
,
4081 dynamic_symbols
, dynstr
);
4084 #ifdef HAVE_TARGET_64_LITTLE
4085 case Parameters::TARGET_64_LITTLE
:
4086 this->sized_create_version_sections
<64, false>(versions
, symtab
,
4088 dynamic_symbols
, dynstr
);
4091 #ifdef HAVE_TARGET_64_BIG
4092 case Parameters::TARGET_64_BIG
:
4093 this->sized_create_version_sections
<64, true>(versions
, symtab
,
4095 dynamic_symbols
, dynstr
);
4103 // Create the version sections, sized version.
4105 template<int size
, bool big_endian
>
4107 Layout::sized_create_version_sections(
4108 const Versions
* versions
,
4109 const Symbol_table
* symtab
,
4110 unsigned int local_symcount
,
4111 const std::vector
<Symbol
*>& dynamic_symbols
,
4112 const Output_section
* dynstr
)
4114 Output_section
* vsec
= this->choose_output_section(NULL
, ".gnu.version",
4115 elfcpp::SHT_GNU_versym
,
4118 ORDER_DYNAMIC_LINKER
,
4121 // Check for NULL since a linker script may discard this section.
4124 unsigned char* vbuf
;
4126 versions
->symbol_section_contents
<size
, big_endian
>(symtab
,
4132 Output_section_data
* vdata
= new Output_data_const_buffer(vbuf
, vsize
, 2,
4135 vsec
->add_output_section_data(vdata
);
4136 vsec
->set_entsize(2);
4137 vsec
->set_link_section(this->dynsym_section_
);
4140 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
4141 if (odyn
!= NULL
&& vsec
!= NULL
)
4142 odyn
->add_section_address(elfcpp::DT_VERSYM
, vsec
);
4144 if (versions
->any_defs())
4146 Output_section
* vdsec
;
4147 vdsec
= this->choose_output_section(NULL
, ".gnu.version_d",
4148 elfcpp::SHT_GNU_verdef
,
4150 false, ORDER_DYNAMIC_LINKER
, false);
4154 unsigned char* vdbuf
;
4155 unsigned int vdsize
;
4156 unsigned int vdentries
;
4157 versions
->def_section_contents
<size
, big_endian
>(&this->dynpool_
,
4161 Output_section_data
* vddata
=
4162 new Output_data_const_buffer(vdbuf
, vdsize
, 4, "** version defs");
4164 vdsec
->add_output_section_data(vddata
);
4165 vdsec
->set_link_section(dynstr
);
4166 vdsec
->set_info(vdentries
);
4170 odyn
->add_section_address(elfcpp::DT_VERDEF
, vdsec
);
4171 odyn
->add_constant(elfcpp::DT_VERDEFNUM
, vdentries
);
4176 if (versions
->any_needs())
4178 Output_section
* vnsec
;
4179 vnsec
= this->choose_output_section(NULL
, ".gnu.version_r",
4180 elfcpp::SHT_GNU_verneed
,
4182 false, ORDER_DYNAMIC_LINKER
, false);
4186 unsigned char* vnbuf
;
4187 unsigned int vnsize
;
4188 unsigned int vnentries
;
4189 versions
->need_section_contents
<size
, big_endian
>(&this->dynpool_
,
4193 Output_section_data
* vndata
=
4194 new Output_data_const_buffer(vnbuf
, vnsize
, 4, "** version refs");
4196 vnsec
->add_output_section_data(vndata
);
4197 vnsec
->set_link_section(dynstr
);
4198 vnsec
->set_info(vnentries
);
4202 odyn
->add_section_address(elfcpp::DT_VERNEED
, vnsec
);
4203 odyn
->add_constant(elfcpp::DT_VERNEEDNUM
, vnentries
);
4209 // Create the .interp section and PT_INTERP segment.
4212 Layout::create_interp(const Target
* target
)
4214 gold_assert(this->interp_segment_
== NULL
);
4216 const char* interp
= parameters
->options().dynamic_linker();
4219 interp
= target
->dynamic_linker();
4220 gold_assert(interp
!= NULL
);
4223 size_t len
= strlen(interp
) + 1;
4225 Output_section_data
* odata
= new Output_data_const(interp
, len
, 1);
4227 Output_section
* osec
= this->choose_output_section(NULL
, ".interp",
4228 elfcpp::SHT_PROGBITS
,
4230 false, ORDER_INTERP
,
4233 osec
->add_output_section_data(odata
);
4236 // Add dynamic tags for the PLT and the dynamic relocs. This is
4237 // called by the target-specific code. This does nothing if not doing
4240 // USE_REL is true for REL relocs rather than RELA relocs.
4242 // If PLT_GOT is not NULL, then DT_PLTGOT points to it.
4244 // If PLT_REL is not NULL, it is used for DT_PLTRELSZ, and DT_JMPREL,
4245 // and we also set DT_PLTREL. We use PLT_REL's output section, since
4246 // some targets have multiple reloc sections in PLT_REL.
4248 // If DYN_REL is not NULL, it is used for DT_REL/DT_RELA,
4249 // DT_RELSZ/DT_RELASZ, DT_RELENT/DT_RELAENT. Again we use the output
4252 // If ADD_DEBUG is true, we add a DT_DEBUG entry when generating an
4256 Layout::add_target_dynamic_tags(bool use_rel
, const Output_data
* plt_got
,
4257 const Output_data
* plt_rel
,
4258 const Output_data_reloc_generic
* dyn_rel
,
4259 bool add_debug
, bool dynrel_includes_plt
)
4261 Output_data_dynamic
* odyn
= this->dynamic_data_
;
4265 if (plt_got
!= NULL
&& plt_got
->output_section() != NULL
)
4266 odyn
->add_section_address(elfcpp::DT_PLTGOT
, plt_got
);
4268 if (plt_rel
!= NULL
&& plt_rel
->output_section() != NULL
)
4270 odyn
->add_section_size(elfcpp::DT_PLTRELSZ
, plt_rel
->output_section());
4271 odyn
->add_section_address(elfcpp::DT_JMPREL
, plt_rel
->output_section());
4272 odyn
->add_constant(elfcpp::DT_PLTREL
,
4273 use_rel
? elfcpp::DT_REL
: elfcpp::DT_RELA
);
4276 if (dyn_rel
!= NULL
&& dyn_rel
->output_section() != NULL
)
4278 odyn
->add_section_address(use_rel
? elfcpp::DT_REL
: elfcpp::DT_RELA
,
4279 dyn_rel
->output_section());
4281 && plt_rel
->output_section() != NULL
4282 && dynrel_includes_plt
)
4283 odyn
->add_section_size(use_rel
? elfcpp::DT_RELSZ
: elfcpp::DT_RELASZ
,
4284 dyn_rel
->output_section(),
4285 plt_rel
->output_section());
4287 odyn
->add_section_size(use_rel
? elfcpp::DT_RELSZ
: elfcpp::DT_RELASZ
,
4288 dyn_rel
->output_section());
4289 const int size
= parameters
->target().get_size();
4294 rel_tag
= elfcpp::DT_RELENT
;
4296 rel_size
= Reloc_types
<elfcpp::SHT_REL
, 32, false>::reloc_size
;
4297 else if (size
== 64)
4298 rel_size
= Reloc_types
<elfcpp::SHT_REL
, 64, false>::reloc_size
;
4304 rel_tag
= elfcpp::DT_RELAENT
;
4306 rel_size
= Reloc_types
<elfcpp::SHT_RELA
, 32, false>::reloc_size
;
4307 else if (size
== 64)
4308 rel_size
= Reloc_types
<elfcpp::SHT_RELA
, 64, false>::reloc_size
;
4312 odyn
->add_constant(rel_tag
, rel_size
);
4314 if (parameters
->options().combreloc())
4316 size_t c
= dyn_rel
->relative_reloc_count();
4318 odyn
->add_constant((use_rel
4319 ? elfcpp::DT_RELCOUNT
4320 : elfcpp::DT_RELACOUNT
),
4325 if (add_debug
&& !parameters
->options().shared())
4327 // The value of the DT_DEBUG tag is filled in by the dynamic
4328 // linker at run time, and used by the debugger.
4329 odyn
->add_constant(elfcpp::DT_DEBUG
, 0);
4333 // Finish the .dynamic section and PT_DYNAMIC segment.
4336 Layout::finish_dynamic_section(const Input_objects
* input_objects
,
4337 const Symbol_table
* symtab
)
4339 if (!this->script_options_
->saw_phdrs_clause()
4340 && this->dynamic_section_
!= NULL
)
4342 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_DYNAMIC
,
4345 oseg
->add_output_section_to_nonload(this->dynamic_section_
,
4346 elfcpp::PF_R
| elfcpp::PF_W
);
4349 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
4353 for (Input_objects::Dynobj_iterator p
= input_objects
->dynobj_begin();
4354 p
!= input_objects
->dynobj_end();
4357 if (!(*p
)->is_needed() && (*p
)->as_needed())
4359 // This dynamic object was linked with --as-needed, but it
4364 odyn
->add_string(elfcpp::DT_NEEDED
, (*p
)->soname());
4367 if (parameters
->options().shared())
4369 const char* soname
= parameters
->options().soname();
4371 odyn
->add_string(elfcpp::DT_SONAME
, soname
);
4374 Symbol
* sym
= symtab
->lookup(parameters
->options().init());
4375 if (sym
!= NULL
&& sym
->is_defined() && !sym
->is_from_dynobj())
4376 odyn
->add_symbol(elfcpp::DT_INIT
, sym
);
4378 sym
= symtab
->lookup(parameters
->options().fini());
4379 if (sym
!= NULL
&& sym
->is_defined() && !sym
->is_from_dynobj())
4380 odyn
->add_symbol(elfcpp::DT_FINI
, sym
);
4382 // Look for .init_array, .preinit_array and .fini_array by checking
4384 for(Layout::Section_list::const_iterator p
= this->section_list_
.begin();
4385 p
!= this->section_list_
.end();
4387 switch((*p
)->type())
4389 case elfcpp::SHT_FINI_ARRAY
:
4390 odyn
->add_section_address(elfcpp::DT_FINI_ARRAY
, *p
);
4391 odyn
->add_section_size(elfcpp::DT_FINI_ARRAYSZ
, *p
);
4393 case elfcpp::SHT_INIT_ARRAY
:
4394 odyn
->add_section_address(elfcpp::DT_INIT_ARRAY
, *p
);
4395 odyn
->add_section_size(elfcpp::DT_INIT_ARRAYSZ
, *p
);
4397 case elfcpp::SHT_PREINIT_ARRAY
:
4398 odyn
->add_section_address(elfcpp::DT_PREINIT_ARRAY
, *p
);
4399 odyn
->add_section_size(elfcpp::DT_PREINIT_ARRAYSZ
, *p
);
4405 // Add a DT_RPATH entry if needed.
4406 const General_options::Dir_list
& rpath(parameters
->options().rpath());
4409 std::string rpath_val
;
4410 for (General_options::Dir_list::const_iterator p
= rpath
.begin();
4414 if (rpath_val
.empty())
4415 rpath_val
= p
->name();
4418 // Eliminate duplicates.
4419 General_options::Dir_list::const_iterator q
;
4420 for (q
= rpath
.begin(); q
!= p
; ++q
)
4421 if (q
->name() == p
->name())
4426 rpath_val
+= p
->name();
4431 odyn
->add_string(elfcpp::DT_RPATH
, rpath_val
);
4432 if (parameters
->options().enable_new_dtags())
4433 odyn
->add_string(elfcpp::DT_RUNPATH
, rpath_val
);
4436 // Look for text segments that have dynamic relocations.
4437 bool have_textrel
= false;
4438 if (!this->script_options_
->saw_sections_clause())
4440 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
4441 p
!= this->segment_list_
.end();
4444 if ((*p
)->type() == elfcpp::PT_LOAD
4445 && ((*p
)->flags() & elfcpp::PF_W
) == 0
4446 && (*p
)->has_dynamic_reloc())
4448 have_textrel
= true;
4455 // We don't know the section -> segment mapping, so we are
4456 // conservative and just look for readonly sections with
4457 // relocations. If those sections wind up in writable segments,
4458 // then we have created an unnecessary DT_TEXTREL entry.
4459 for (Section_list::const_iterator p
= this->section_list_
.begin();
4460 p
!= this->section_list_
.end();
4463 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0
4464 && ((*p
)->flags() & elfcpp::SHF_WRITE
) == 0
4465 && (*p
)->has_dynamic_reloc())
4467 have_textrel
= true;
4473 if (parameters
->options().filter() != NULL
)
4474 odyn
->add_string(elfcpp::DT_FILTER
, parameters
->options().filter());
4475 if (parameters
->options().any_auxiliary())
4477 for (options::String_set::const_iterator p
=
4478 parameters
->options().auxiliary_begin();
4479 p
!= parameters
->options().auxiliary_end();
4481 odyn
->add_string(elfcpp::DT_AUXILIARY
, *p
);
4484 // Add a DT_FLAGS entry if necessary.
4485 unsigned int flags
= 0;
4488 // Add a DT_TEXTREL for compatibility with older loaders.
4489 odyn
->add_constant(elfcpp::DT_TEXTREL
, 0);
4490 flags
|= elfcpp::DF_TEXTREL
;
4492 if (parameters
->options().text())
4493 gold_error(_("read-only segment has dynamic relocations"));
4494 else if (parameters
->options().warn_shared_textrel()
4495 && parameters
->options().shared())
4496 gold_warning(_("shared library text segment is not shareable"));
4498 if (parameters
->options().shared() && this->has_static_tls())
4499 flags
|= elfcpp::DF_STATIC_TLS
;
4500 if (parameters
->options().origin())
4501 flags
|= elfcpp::DF_ORIGIN
;
4502 if (parameters
->options().Bsymbolic())
4504 flags
|= elfcpp::DF_SYMBOLIC
;
4505 // Add DT_SYMBOLIC for compatibility with older loaders.
4506 odyn
->add_constant(elfcpp::DT_SYMBOLIC
, 0);
4508 if (parameters
->options().now())
4509 flags
|= elfcpp::DF_BIND_NOW
;
4511 odyn
->add_constant(elfcpp::DT_FLAGS
, flags
);
4514 if (parameters
->options().initfirst())
4515 flags
|= elfcpp::DF_1_INITFIRST
;
4516 if (parameters
->options().interpose())
4517 flags
|= elfcpp::DF_1_INTERPOSE
;
4518 if (parameters
->options().loadfltr())
4519 flags
|= elfcpp::DF_1_LOADFLTR
;
4520 if (parameters
->options().nodefaultlib())
4521 flags
|= elfcpp::DF_1_NODEFLIB
;
4522 if (parameters
->options().nodelete())
4523 flags
|= elfcpp::DF_1_NODELETE
;
4524 if (parameters
->options().nodlopen())
4525 flags
|= elfcpp::DF_1_NOOPEN
;
4526 if (parameters
->options().nodump())
4527 flags
|= elfcpp::DF_1_NODUMP
;
4528 if (!parameters
->options().shared())
4529 flags
&= ~(elfcpp::DF_1_INITFIRST
4530 | elfcpp::DF_1_NODELETE
4531 | elfcpp::DF_1_NOOPEN
);
4532 if (parameters
->options().origin())
4533 flags
|= elfcpp::DF_1_ORIGIN
;
4534 if (parameters
->options().now())
4535 flags
|= elfcpp::DF_1_NOW
;
4536 if (parameters
->options().Bgroup())
4537 flags
|= elfcpp::DF_1_GROUP
;
4539 odyn
->add_constant(elfcpp::DT_FLAGS_1
, flags
);
4542 // Set the size of the _DYNAMIC symbol table to be the size of the
4546 Layout::set_dynamic_symbol_size(const Symbol_table
* symtab
)
4548 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
4551 odyn
->finalize_data_size();
4552 if (this->dynamic_symbol_
== NULL
)
4554 off_t data_size
= odyn
->data_size();
4555 const int size
= parameters
->target().get_size();
4557 symtab
->get_sized_symbol
<32>(this->dynamic_symbol_
)->set_symsize(data_size
);
4558 else if (size
== 64)
4559 symtab
->get_sized_symbol
<64>(this->dynamic_symbol_
)->set_symsize(data_size
);
4564 // The mapping of input section name prefixes to output section names.
4565 // In some cases one prefix is itself a prefix of another prefix; in
4566 // such a case the longer prefix must come first. These prefixes are
4567 // based on the GNU linker default ELF linker script.
4569 #define MAPPING_INIT(f, t) { f, sizeof(f) - 1, t, sizeof(t) - 1 }
4570 const Layout::Section_name_mapping
Layout::section_name_mapping
[] =
4572 MAPPING_INIT(".text.", ".text"),
4573 MAPPING_INIT(".rodata.", ".rodata"),
4574 MAPPING_INIT(".data.rel.ro.local", ".data.rel.ro.local"),
4575 MAPPING_INIT(".data.rel.ro", ".data.rel.ro"),
4576 MAPPING_INIT(".data.", ".data"),
4577 MAPPING_INIT(".bss.", ".bss"),
4578 MAPPING_INIT(".tdata.", ".tdata"),
4579 MAPPING_INIT(".tbss.", ".tbss"),
4580 MAPPING_INIT(".init_array.", ".init_array"),
4581 MAPPING_INIT(".fini_array.", ".fini_array"),
4582 MAPPING_INIT(".sdata.", ".sdata"),
4583 MAPPING_INIT(".sbss.", ".sbss"),
4584 // FIXME: In the GNU linker, .sbss2 and .sdata2 are handled
4585 // differently depending on whether it is creating a shared library.
4586 MAPPING_INIT(".sdata2.", ".sdata"),
4587 MAPPING_INIT(".sbss2.", ".sbss"),
4588 MAPPING_INIT(".lrodata.", ".lrodata"),
4589 MAPPING_INIT(".ldata.", ".ldata"),
4590 MAPPING_INIT(".lbss.", ".lbss"),
4591 MAPPING_INIT(".gcc_except_table.", ".gcc_except_table"),
4592 MAPPING_INIT(".gnu.linkonce.d.rel.ro.local.", ".data.rel.ro.local"),
4593 MAPPING_INIT(".gnu.linkonce.d.rel.ro.", ".data.rel.ro"),
4594 MAPPING_INIT(".gnu.linkonce.t.", ".text"),
4595 MAPPING_INIT(".gnu.linkonce.r.", ".rodata"),
4596 MAPPING_INIT(".gnu.linkonce.d.", ".data"),
4597 MAPPING_INIT(".gnu.linkonce.b.", ".bss"),
4598 MAPPING_INIT(".gnu.linkonce.s.", ".sdata"),
4599 MAPPING_INIT(".gnu.linkonce.sb.", ".sbss"),
4600 MAPPING_INIT(".gnu.linkonce.s2.", ".sdata"),
4601 MAPPING_INIT(".gnu.linkonce.sb2.", ".sbss"),
4602 MAPPING_INIT(".gnu.linkonce.wi.", ".debug_info"),
4603 MAPPING_INIT(".gnu.linkonce.td.", ".tdata"),
4604 MAPPING_INIT(".gnu.linkonce.tb.", ".tbss"),
4605 MAPPING_INIT(".gnu.linkonce.lr.", ".lrodata"),
4606 MAPPING_INIT(".gnu.linkonce.l.", ".ldata"),
4607 MAPPING_INIT(".gnu.linkonce.lb.", ".lbss"),
4608 MAPPING_INIT(".ARM.extab", ".ARM.extab"),
4609 MAPPING_INIT(".gnu.linkonce.armextab.", ".ARM.extab"),
4610 MAPPING_INIT(".ARM.exidx", ".ARM.exidx"),
4611 MAPPING_INIT(".gnu.linkonce.armexidx.", ".ARM.exidx"),
4615 const int Layout::section_name_mapping_count
=
4616 (sizeof(Layout::section_name_mapping
)
4617 / sizeof(Layout::section_name_mapping
[0]));
4619 // Choose the output section name to use given an input section name.
4620 // Set *PLEN to the length of the name. *PLEN is initialized to the
4624 Layout::output_section_name(const Relobj
* relobj
, const char* name
,
4627 // gcc 4.3 generates the following sorts of section names when it
4628 // needs a section name specific to a function:
4634 // .data.rel.local.FN
4636 // .data.rel.ro.local.FN
4643 // The GNU linker maps all of those to the part before the .FN,
4644 // except that .data.rel.local.FN is mapped to .data, and
4645 // .data.rel.ro.local.FN is mapped to .data.rel.ro. The sections
4646 // beginning with .data.rel.ro.local are grouped together.
4648 // For an anonymous namespace, the string FN can contain a '.'.
4650 // Also of interest: .rodata.strN.N, .rodata.cstN, both of which the
4651 // GNU linker maps to .rodata.
4653 // The .data.rel.ro sections are used with -z relro. The sections
4654 // are recognized by name. We use the same names that the GNU
4655 // linker does for these sections.
4657 // It is hard to handle this in a principled way, so we don't even
4658 // try. We use a table of mappings. If the input section name is
4659 // not found in the table, we simply use it as the output section
4662 const Section_name_mapping
* psnm
= section_name_mapping
;
4663 for (int i
= 0; i
< section_name_mapping_count
; ++i
, ++psnm
)
4665 if (strncmp(name
, psnm
->from
, psnm
->fromlen
) == 0)
4667 *plen
= psnm
->tolen
;
4672 // As an additional complication, .ctors sections are output in
4673 // either .ctors or .init_array sections, and .dtors sections are
4674 // output in either .dtors or .fini_array sections.
4675 if (is_prefix_of(".ctors.", name
) || is_prefix_of(".dtors.", name
))
4677 if (parameters
->options().ctors_in_init_array())
4680 return name
[1] == 'c' ? ".init_array" : ".fini_array";
4685 return name
[1] == 'c' ? ".ctors" : ".dtors";
4688 if (parameters
->options().ctors_in_init_array()
4689 && (strcmp(name
, ".ctors") == 0 || strcmp(name
, ".dtors") == 0))
4691 // To make .init_array/.fini_array work with gcc we must exclude
4692 // .ctors and .dtors sections from the crtbegin and crtend
4695 || (!Layout::match_file_name(relobj
, "crtbegin")
4696 && !Layout::match_file_name(relobj
, "crtend")))
4699 return name
[1] == 'c' ? ".init_array" : ".fini_array";
4706 // Return true if RELOBJ is an input file whose base name matches
4707 // FILE_NAME. The base name must have an extension of ".o", and must
4708 // be exactly FILE_NAME.o or FILE_NAME, one character, ".o". This is
4709 // to match crtbegin.o as well as crtbeginS.o without getting confused
4710 // by other possibilities. Overall matching the file name this way is
4711 // a dreadful hack, but the GNU linker does it in order to better
4712 // support gcc, and we need to be compatible.
4715 Layout::match_file_name(const Relobj
* relobj
, const char* match
)
4717 const std::string
& file_name(relobj
->name());
4718 const char* base_name
= lbasename(file_name
.c_str());
4719 size_t match_len
= strlen(match
);
4720 if (strncmp(base_name
, match
, match_len
) != 0)
4722 size_t base_len
= strlen(base_name
);
4723 if (base_len
!= match_len
+ 2 && base_len
!= match_len
+ 3)
4725 return memcmp(base_name
+ base_len
- 2, ".o", 2) == 0;
4728 // Check if a comdat group or .gnu.linkonce section with the given
4729 // NAME is selected for the link. If there is already a section,
4730 // *KEPT_SECTION is set to point to the existing section and the
4731 // function returns false. Otherwise, OBJECT, SHNDX, IS_COMDAT, and
4732 // IS_GROUP_NAME are recorded for this NAME in the layout object,
4733 // *KEPT_SECTION is set to the internal copy and the function returns
4737 Layout::find_or_add_kept_section(const std::string
& name
,
4742 Kept_section
** kept_section
)
4744 // It's normal to see a couple of entries here, for the x86 thunk
4745 // sections. If we see more than a few, we're linking a C++
4746 // program, and we resize to get more space to minimize rehashing.
4747 if (this->signatures_
.size() > 4
4748 && !this->resized_signatures_
)
4750 reserve_unordered_map(&this->signatures_
,
4751 this->number_of_input_files_
* 64);
4752 this->resized_signatures_
= true;
4755 Kept_section candidate
;
4756 std::pair
<Signatures::iterator
, bool> ins
=
4757 this->signatures_
.insert(std::make_pair(name
, candidate
));
4759 if (kept_section
!= NULL
)
4760 *kept_section
= &ins
.first
->second
;
4763 // This is the first time we've seen this signature.
4764 ins
.first
->second
.set_object(object
);
4765 ins
.first
->second
.set_shndx(shndx
);
4767 ins
.first
->second
.set_is_comdat();
4769 ins
.first
->second
.set_is_group_name();
4773 // We have already seen this signature.
4775 if (ins
.first
->second
.is_group_name())
4777 // We've already seen a real section group with this signature.
4778 // If the kept group is from a plugin object, and we're in the
4779 // replacement phase, accept the new one as a replacement.
4780 if (ins
.first
->second
.object() == NULL
4781 && parameters
->options().plugins()->in_replacement_phase())
4783 ins
.first
->second
.set_object(object
);
4784 ins
.first
->second
.set_shndx(shndx
);
4789 else if (is_group_name
)
4791 // This is a real section group, and we've already seen a
4792 // linkonce section with this signature. Record that we've seen
4793 // a section group, and don't include this section group.
4794 ins
.first
->second
.set_is_group_name();
4799 // We've already seen a linkonce section and this is a linkonce
4800 // section. These don't block each other--this may be the same
4801 // symbol name with different section types.
4806 // Store the allocated sections into the section list.
4809 Layout::get_allocated_sections(Section_list
* section_list
) const
4811 for (Section_list::const_iterator p
= this->section_list_
.begin();
4812 p
!= this->section_list_
.end();
4814 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0)
4815 section_list
->push_back(*p
);
4818 // Create an output segment.
4821 Layout::make_output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
4823 gold_assert(!parameters
->options().relocatable());
4824 Output_segment
* oseg
= new Output_segment(type
, flags
);
4825 this->segment_list_
.push_back(oseg
);
4827 if (type
== elfcpp::PT_TLS
)
4828 this->tls_segment_
= oseg
;
4829 else if (type
== elfcpp::PT_GNU_RELRO
)
4830 this->relro_segment_
= oseg
;
4831 else if (type
== elfcpp::PT_INTERP
)
4832 this->interp_segment_
= oseg
;
4837 // Return the file offset of the normal symbol table.
4840 Layout::symtab_section_offset() const
4842 if (this->symtab_section_
!= NULL
)
4843 return this->symtab_section_
->offset();
4847 // Return the section index of the normal symbol table. It may have
4848 // been stripped by the -s/--strip-all option.
4851 Layout::symtab_section_shndx() const
4853 if (this->symtab_section_
!= NULL
)
4854 return this->symtab_section_
->out_shndx();
4858 // Write out the Output_sections. Most won't have anything to write,
4859 // since most of the data will come from input sections which are
4860 // handled elsewhere. But some Output_sections do have Output_data.
4863 Layout::write_output_sections(Output_file
* of
) const
4865 for (Section_list::const_iterator p
= this->section_list_
.begin();
4866 p
!= this->section_list_
.end();
4869 if (!(*p
)->after_input_sections())
4874 // Write out data not associated with a section or the symbol table.
4877 Layout::write_data(const Symbol_table
* symtab
, Output_file
* of
) const
4879 if (!parameters
->options().strip_all())
4881 const Output_section
* symtab_section
= this->symtab_section_
;
4882 for (Section_list::const_iterator p
= this->section_list_
.begin();
4883 p
!= this->section_list_
.end();
4886 if ((*p
)->needs_symtab_index())
4888 gold_assert(symtab_section
!= NULL
);
4889 unsigned int index
= (*p
)->symtab_index();
4890 gold_assert(index
> 0 && index
!= -1U);
4891 off_t off
= (symtab_section
->offset()
4892 + index
* symtab_section
->entsize());
4893 symtab
->write_section_symbol(*p
, this->symtab_xindex_
, of
, off
);
4898 const Output_section
* dynsym_section
= this->dynsym_section_
;
4899 for (Section_list::const_iterator p
= this->section_list_
.begin();
4900 p
!= this->section_list_
.end();
4903 if ((*p
)->needs_dynsym_index())
4905 gold_assert(dynsym_section
!= NULL
);
4906 unsigned int index
= (*p
)->dynsym_index();
4907 gold_assert(index
> 0 && index
!= -1U);
4908 off_t off
= (dynsym_section
->offset()
4909 + index
* dynsym_section
->entsize());
4910 symtab
->write_section_symbol(*p
, this->dynsym_xindex_
, of
, off
);
4914 // Write out the Output_data which are not in an Output_section.
4915 for (Data_list::const_iterator p
= this->special_output_list_
.begin();
4916 p
!= this->special_output_list_
.end();
4921 // Write out the Output_sections which can only be written after the
4922 // input sections are complete.
4925 Layout::write_sections_after_input_sections(Output_file
* of
)
4927 // Determine the final section offsets, and thus the final output
4928 // file size. Note we finalize the .shstrab last, to allow the
4929 // after_input_section sections to modify their section-names before
4931 if (this->any_postprocessing_sections_
)
4933 off_t off
= this->output_file_size_
;
4934 off
= this->set_section_offsets(off
, POSTPROCESSING_SECTIONS_PASS
);
4936 // Now that we've finalized the names, we can finalize the shstrab.
4938 this->set_section_offsets(off
,
4939 STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
);
4941 if (off
> this->output_file_size_
)
4944 this->output_file_size_
= off
;
4948 for (Section_list::const_iterator p
= this->section_list_
.begin();
4949 p
!= this->section_list_
.end();
4952 if ((*p
)->after_input_sections())
4956 this->section_headers_
->write(of
);
4959 // If the build ID requires computing a checksum, do so here, and
4960 // write it out. We compute a checksum over the entire file because
4961 // that is simplest.
4964 Layout::write_build_id(Output_file
* of
) const
4966 if (this->build_id_note_
== NULL
)
4969 const unsigned char* iv
= of
->get_input_view(0, this->output_file_size_
);
4971 unsigned char* ov
= of
->get_output_view(this->build_id_note_
->offset(),
4972 this->build_id_note_
->data_size());
4974 const char* style
= parameters
->options().build_id();
4975 if (strcmp(style
, "sha1") == 0)
4978 sha1_init_ctx(&ctx
);
4979 sha1_process_bytes(iv
, this->output_file_size_
, &ctx
);
4980 sha1_finish_ctx(&ctx
, ov
);
4982 else if (strcmp(style
, "md5") == 0)
4986 md5_process_bytes(iv
, this->output_file_size_
, &ctx
);
4987 md5_finish_ctx(&ctx
, ov
);
4992 of
->write_output_view(this->build_id_note_
->offset(),
4993 this->build_id_note_
->data_size(),
4996 of
->free_input_view(0, this->output_file_size_
, iv
);
4999 // Write out a binary file. This is called after the link is
5000 // complete. IN is the temporary output file we used to generate the
5001 // ELF code. We simply walk through the segments, read them from
5002 // their file offset in IN, and write them to their load address in
5003 // the output file. FIXME: with a bit more work, we could support
5004 // S-records and/or Intel hex format here.
5007 Layout::write_binary(Output_file
* in
) const
5009 gold_assert(parameters
->options().oformat_enum()
5010 == General_options::OBJECT_FORMAT_BINARY
);
5012 // Get the size of the binary file.
5013 uint64_t max_load_address
= 0;
5014 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
5015 p
!= this->segment_list_
.end();
5018 if ((*p
)->type() == elfcpp::PT_LOAD
&& (*p
)->filesz() > 0)
5020 uint64_t max_paddr
= (*p
)->paddr() + (*p
)->filesz();
5021 if (max_paddr
> max_load_address
)
5022 max_load_address
= max_paddr
;
5026 Output_file
out(parameters
->options().output_file_name());
5027 out
.open(max_load_address
);
5029 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
5030 p
!= this->segment_list_
.end();
5033 if ((*p
)->type() == elfcpp::PT_LOAD
&& (*p
)->filesz() > 0)
5035 const unsigned char* vin
= in
->get_input_view((*p
)->offset(),
5037 unsigned char* vout
= out
.get_output_view((*p
)->paddr(),
5039 memcpy(vout
, vin
, (*p
)->filesz());
5040 out
.write_output_view((*p
)->paddr(), (*p
)->filesz(), vout
);
5041 in
->free_input_view((*p
)->offset(), (*p
)->filesz(), vin
);
5048 // Print the output sections to the map file.
5051 Layout::print_to_mapfile(Mapfile
* mapfile
) const
5053 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
5054 p
!= this->segment_list_
.end();
5056 (*p
)->print_sections_to_mapfile(mapfile
);
5059 // Print statistical information to stderr. This is used for --stats.
5062 Layout::print_stats() const
5064 this->namepool_
.print_stats("section name pool");
5065 this->sympool_
.print_stats("output symbol name pool");
5066 this->dynpool_
.print_stats("dynamic name pool");
5068 for (Section_list::const_iterator p
= this->section_list_
.begin();
5069 p
!= this->section_list_
.end();
5071 (*p
)->print_merge_stats();
5074 // Write_sections_task methods.
5076 // We can always run this task.
5079 Write_sections_task::is_runnable()
5084 // We need to unlock both OUTPUT_SECTIONS_BLOCKER and FINAL_BLOCKER
5088 Write_sections_task::locks(Task_locker
* tl
)
5090 tl
->add(this, this->output_sections_blocker_
);
5091 tl
->add(this, this->final_blocker_
);
5094 // Run the task--write out the data.
5097 Write_sections_task::run(Workqueue
*)
5099 this->layout_
->write_output_sections(this->of_
);
5102 // Write_data_task methods.
5104 // We can always run this task.
5107 Write_data_task::is_runnable()
5112 // We need to unlock FINAL_BLOCKER when finished.
5115 Write_data_task::locks(Task_locker
* tl
)
5117 tl
->add(this, this->final_blocker_
);
5120 // Run the task--write out the data.
5123 Write_data_task::run(Workqueue
*)
5125 this->layout_
->write_data(this->symtab_
, this->of_
);
5128 // Write_symbols_task methods.
5130 // We can always run this task.
5133 Write_symbols_task::is_runnable()
5138 // We need to unlock FINAL_BLOCKER when finished.
5141 Write_symbols_task::locks(Task_locker
* tl
)
5143 tl
->add(this, this->final_blocker_
);
5146 // Run the task--write out the symbols.
5149 Write_symbols_task::run(Workqueue
*)
5151 this->symtab_
->write_globals(this->sympool_
, this->dynpool_
,
5152 this->layout_
->symtab_xindex(),
5153 this->layout_
->dynsym_xindex(), this->of_
);
5156 // Write_after_input_sections_task methods.
5158 // We can only run this task after the input sections have completed.
5161 Write_after_input_sections_task::is_runnable()
5163 if (this->input_sections_blocker_
->is_blocked())
5164 return this->input_sections_blocker_
;
5168 // We need to unlock FINAL_BLOCKER when finished.
5171 Write_after_input_sections_task::locks(Task_locker
* tl
)
5173 tl
->add(this, this->final_blocker_
);
5179 Write_after_input_sections_task::run(Workqueue
*)
5181 this->layout_
->write_sections_after_input_sections(this->of_
);
5184 // Close_task_runner methods.
5186 // Run the task--close the file.
5189 Close_task_runner::run(Workqueue
*, const Task
*)
5191 // If we need to compute a checksum for the BUILD if, we do so here.
5192 this->layout_
->write_build_id(this->of_
);
5194 // If we've been asked to create a binary file, we do so here.
5195 if (this->options_
->oformat_enum() != General_options::OBJECT_FORMAT_ELF
)
5196 this->layout_
->write_binary(this->of_
);
5201 // Instantiate the templates we need. We could use the configure
5202 // script to restrict this to only the ones for implemented targets.
5204 #ifdef HAVE_TARGET_32_LITTLE
5207 Layout::init_fixed_output_section
<32, false>(
5209 elfcpp::Shdr
<32, false>& shdr
);
5212 #ifdef HAVE_TARGET_32_BIG
5215 Layout::init_fixed_output_section
<32, true>(
5217 elfcpp::Shdr
<32, true>& shdr
);
5220 #ifdef HAVE_TARGET_64_LITTLE
5223 Layout::init_fixed_output_section
<64, false>(
5225 elfcpp::Shdr
<64, false>& shdr
);
5228 #ifdef HAVE_TARGET_64_BIG
5231 Layout::init_fixed_output_section
<64, true>(
5233 elfcpp::Shdr
<64, true>& shdr
);
5236 #ifdef HAVE_TARGET_32_LITTLE
5239 Layout::layout
<32, false>(Sized_relobj_file
<32, false>* object
,
5242 const elfcpp::Shdr
<32, false>& shdr
,
5243 unsigned int, unsigned int, off_t
*);
5246 #ifdef HAVE_TARGET_32_BIG
5249 Layout::layout
<32, true>(Sized_relobj_file
<32, true>* object
,
5252 const elfcpp::Shdr
<32, true>& shdr
,
5253 unsigned int, unsigned int, off_t
*);
5256 #ifdef HAVE_TARGET_64_LITTLE
5259 Layout::layout
<64, false>(Sized_relobj_file
<64, false>* object
,
5262 const elfcpp::Shdr
<64, false>& shdr
,
5263 unsigned int, unsigned int, off_t
*);
5266 #ifdef HAVE_TARGET_64_BIG
5269 Layout::layout
<64, true>(Sized_relobj_file
<64, true>* object
,
5272 const elfcpp::Shdr
<64, true>& shdr
,
5273 unsigned int, unsigned int, off_t
*);
5276 #ifdef HAVE_TARGET_32_LITTLE
5279 Layout::layout_reloc
<32, false>(Sized_relobj_file
<32, false>* object
,
5280 unsigned int reloc_shndx
,
5281 const elfcpp::Shdr
<32, false>& shdr
,
5282 Output_section
* data_section
,
5283 Relocatable_relocs
* rr
);
5286 #ifdef HAVE_TARGET_32_BIG
5289 Layout::layout_reloc
<32, true>(Sized_relobj_file
<32, true>* object
,
5290 unsigned int reloc_shndx
,
5291 const elfcpp::Shdr
<32, true>& shdr
,
5292 Output_section
* data_section
,
5293 Relocatable_relocs
* rr
);
5296 #ifdef HAVE_TARGET_64_LITTLE
5299 Layout::layout_reloc
<64, false>(Sized_relobj_file
<64, false>* object
,
5300 unsigned int reloc_shndx
,
5301 const elfcpp::Shdr
<64, false>& shdr
,
5302 Output_section
* data_section
,
5303 Relocatable_relocs
* rr
);
5306 #ifdef HAVE_TARGET_64_BIG
5309 Layout::layout_reloc
<64, true>(Sized_relobj_file
<64, true>* object
,
5310 unsigned int reloc_shndx
,
5311 const elfcpp::Shdr
<64, true>& shdr
,
5312 Output_section
* data_section
,
5313 Relocatable_relocs
* rr
);
5316 #ifdef HAVE_TARGET_32_LITTLE
5319 Layout::layout_group
<32, false>(Symbol_table
* symtab
,
5320 Sized_relobj_file
<32, false>* object
,
5322 const char* group_section_name
,
5323 const char* signature
,
5324 const elfcpp::Shdr
<32, false>& shdr
,
5325 elfcpp::Elf_Word flags
,
5326 std::vector
<unsigned int>* shndxes
);
5329 #ifdef HAVE_TARGET_32_BIG
5332 Layout::layout_group
<32, true>(Symbol_table
* symtab
,
5333 Sized_relobj_file
<32, true>* object
,
5335 const char* group_section_name
,
5336 const char* signature
,
5337 const elfcpp::Shdr
<32, true>& shdr
,
5338 elfcpp::Elf_Word flags
,
5339 std::vector
<unsigned int>* shndxes
);
5342 #ifdef HAVE_TARGET_64_LITTLE
5345 Layout::layout_group
<64, false>(Symbol_table
* symtab
,
5346 Sized_relobj_file
<64, false>* object
,
5348 const char* group_section_name
,
5349 const char* signature
,
5350 const elfcpp::Shdr
<64, false>& shdr
,
5351 elfcpp::Elf_Word flags
,
5352 std::vector
<unsigned int>* shndxes
);
5355 #ifdef HAVE_TARGET_64_BIG
5358 Layout::layout_group
<64, true>(Symbol_table
* symtab
,
5359 Sized_relobj_file
<64, true>* object
,
5361 const char* group_section_name
,
5362 const char* signature
,
5363 const elfcpp::Shdr
<64, true>& shdr
,
5364 elfcpp::Elf_Word flags
,
5365 std::vector
<unsigned int>* shndxes
);
5368 #ifdef HAVE_TARGET_32_LITTLE
5371 Layout::layout_eh_frame
<32, false>(Sized_relobj_file
<32, false>* object
,
5372 const unsigned char* symbols
,
5374 const unsigned char* symbol_names
,
5375 off_t symbol_names_size
,
5377 const elfcpp::Shdr
<32, false>& shdr
,
5378 unsigned int reloc_shndx
,
5379 unsigned int reloc_type
,
5383 #ifdef HAVE_TARGET_32_BIG
5386 Layout::layout_eh_frame
<32, true>(Sized_relobj_file
<32, true>* object
,
5387 const unsigned char* symbols
,
5389 const unsigned char* symbol_names
,
5390 off_t symbol_names_size
,
5392 const elfcpp::Shdr
<32, true>& shdr
,
5393 unsigned int reloc_shndx
,
5394 unsigned int reloc_type
,
5398 #ifdef HAVE_TARGET_64_LITTLE
5401 Layout::layout_eh_frame
<64, false>(Sized_relobj_file
<64, false>* object
,
5402 const unsigned char* symbols
,
5404 const unsigned char* symbol_names
,
5405 off_t symbol_names_size
,
5407 const elfcpp::Shdr
<64, false>& shdr
,
5408 unsigned int reloc_shndx
,
5409 unsigned int reloc_type
,
5413 #ifdef HAVE_TARGET_64_BIG
5416 Layout::layout_eh_frame
<64, true>(Sized_relobj_file
<64, true>* object
,
5417 const unsigned char* symbols
,
5419 const unsigned char* symbol_names
,
5420 off_t symbol_names_size
,
5422 const elfcpp::Shdr
<64, true>& shdr
,
5423 unsigned int reloc_shndx
,
5424 unsigned int reloc_type
,
5428 #ifdef HAVE_TARGET_32_LITTLE
5431 Layout::add_to_gdb_index(bool is_type_unit
,
5432 Sized_relobj
<32, false>* object
,
5433 const unsigned char* symbols
,
5436 unsigned int reloc_shndx
,
5437 unsigned int reloc_type
);
5440 #ifdef HAVE_TARGET_32_BIG
5443 Layout::add_to_gdb_index(bool is_type_unit
,
5444 Sized_relobj
<32, true>* object
,
5445 const unsigned char* symbols
,
5448 unsigned int reloc_shndx
,
5449 unsigned int reloc_type
);
5452 #ifdef HAVE_TARGET_64_LITTLE
5455 Layout::add_to_gdb_index(bool is_type_unit
,
5456 Sized_relobj
<64, false>* object
,
5457 const unsigned char* symbols
,
5460 unsigned int reloc_shndx
,
5461 unsigned int reloc_type
);
5464 #ifdef HAVE_TARGET_64_BIG
5467 Layout::add_to_gdb_index(bool is_type_unit
,
5468 Sized_relobj
<64, true>* object
,
5469 const unsigned char* symbols
,
5472 unsigned int reloc_shndx
,
5473 unsigned int reloc_type
);
5476 } // End namespace gold.