1 // layout.cc -- lay out output file sections for gold
3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
4 // Written by Ian Lance Taylor <iant@google.com>.
6 // This file is part of gold.
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 3 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
21 // MA 02110-1301, USA.
34 #include "libiberty.h"
38 #include "parameters.h"
42 #include "script-sections.h"
47 #include "gdb-index.h"
48 #include "compressed_output.h"
49 #include "reduced_debug_output.h"
52 #include "descriptors.h"
54 #include "incremental.h"
62 // The total number of free lists used.
63 unsigned int Free_list::num_lists
= 0;
64 // The total number of free list nodes used.
65 unsigned int Free_list::num_nodes
= 0;
66 // The total number of calls to Free_list::remove.
67 unsigned int Free_list::num_removes
= 0;
68 // The total number of nodes visited during calls to Free_list::remove.
69 unsigned int Free_list::num_remove_visits
= 0;
70 // The total number of calls to Free_list::allocate.
71 unsigned int Free_list::num_allocates
= 0;
72 // The total number of nodes visited during calls to Free_list::allocate.
73 unsigned int Free_list::num_allocate_visits
= 0;
75 // Initialize the free list. Creates a single free list node that
76 // describes the entire region of length LEN. If EXTEND is true,
77 // allocate() is allowed to extend the region beyond its initial
81 Free_list::init(off_t len
, bool extend
)
83 this->list_
.push_front(Free_list_node(0, len
));
84 this->last_remove_
= this->list_
.begin();
85 this->extend_
= extend
;
87 ++Free_list::num_lists
;
88 ++Free_list::num_nodes
;
91 // Remove a chunk from the free list. Because we start with a single
92 // node that covers the entire section, and remove chunks from it one
93 // at a time, we do not need to coalesce chunks or handle cases that
94 // span more than one free node. We expect to remove chunks from the
95 // free list in order, and we expect to have only a few chunks of free
96 // space left (corresponding to files that have changed since the last
97 // incremental link), so a simple linear list should provide sufficient
101 Free_list::remove(off_t start
, off_t end
)
105 gold_assert(start
< end
);
107 ++Free_list::num_removes
;
109 Iterator p
= this->last_remove_
;
110 if (p
->start_
> start
)
111 p
= this->list_
.begin();
113 for (; p
!= this->list_
.end(); ++p
)
115 ++Free_list::num_remove_visits
;
116 // Find a node that wholly contains the indicated region.
117 if (p
->start_
<= start
&& p
->end_
>= end
)
119 // Case 1: the indicated region spans the whole node.
120 // Add some fuzz to avoid creating tiny free chunks.
121 if (p
->start_
+ 3 >= start
&& p
->end_
<= end
+ 3)
122 p
= this->list_
.erase(p
);
123 // Case 2: remove a chunk from the start of the node.
124 else if (p
->start_
+ 3 >= start
)
126 // Case 3: remove a chunk from the end of the node.
127 else if (p
->end_
<= end
+ 3)
129 // Case 4: remove a chunk from the middle, and split
130 // the node into two.
133 Free_list_node
newnode(p
->start_
, start
);
135 this->list_
.insert(p
, newnode
);
136 ++Free_list::num_nodes
;
138 this->last_remove_
= p
;
143 // Did not find a node containing the given chunk. This could happen
144 // because a small chunk was already removed due to the fuzz.
145 gold_debug(DEBUG_INCREMENTAL
,
146 "Free_list::remove(%d,%d) not found",
147 static_cast<int>(start
), static_cast<int>(end
));
150 // Allocate a chunk of size LEN from the free list. Returns -1ULL
151 // if a sufficiently large chunk of free space is not found.
152 // We use a simple first-fit algorithm.
155 Free_list::allocate(off_t len
, uint64_t align
, off_t minoff
)
157 gold_debug(DEBUG_INCREMENTAL
,
158 "Free_list::allocate(%08lx, %d, %08lx)",
159 static_cast<long>(len
), static_cast<int>(align
),
160 static_cast<long>(minoff
));
162 return align_address(minoff
, align
);
164 ++Free_list::num_allocates
;
166 // We usually want to drop free chunks smaller than 4 bytes.
167 // If we need to guarantee a minimum hole size, though, we need
168 // to keep track of all free chunks.
169 const int fuzz
= this->min_hole_
> 0 ? 0 : 3;
171 for (Iterator p
= this->list_
.begin(); p
!= this->list_
.end(); ++p
)
173 ++Free_list::num_allocate_visits
;
174 off_t start
= p
->start_
> minoff
? p
->start_
: minoff
;
175 start
= align_address(start
, align
);
176 off_t end
= start
+ len
;
177 if (end
> p
->end_
&& p
->end_
== this->length_
&& this->extend_
)
182 if (end
== p
->end_
|| (end
<= p
->end_
- this->min_hole_
))
184 if (p
->start_
+ fuzz
>= start
&& p
->end_
<= end
+ fuzz
)
185 this->list_
.erase(p
);
186 else if (p
->start_
+ fuzz
>= start
)
188 else if (p
->end_
<= end
+ fuzz
)
192 Free_list_node
newnode(p
->start_
, start
);
194 this->list_
.insert(p
, newnode
);
195 ++Free_list::num_nodes
;
202 off_t start
= align_address(this->length_
, align
);
203 this->length_
= start
+ len
;
209 // Dump the free list (for debugging).
213 gold_info("Free list:\n start end length\n");
214 for (Iterator p
= this->list_
.begin(); p
!= this->list_
.end(); ++p
)
215 gold_info(" %08lx %08lx %08lx", static_cast<long>(p
->start_
),
216 static_cast<long>(p
->end_
),
217 static_cast<long>(p
->end_
- p
->start_
));
220 // Print the statistics for the free lists.
222 Free_list::print_stats()
224 fprintf(stderr
, _("%s: total free lists: %u\n"),
225 program_name
, Free_list::num_lists
);
226 fprintf(stderr
, _("%s: total free list nodes: %u\n"),
227 program_name
, Free_list::num_nodes
);
228 fprintf(stderr
, _("%s: calls to Free_list::remove: %u\n"),
229 program_name
, Free_list::num_removes
);
230 fprintf(stderr
, _("%s: nodes visited: %u\n"),
231 program_name
, Free_list::num_remove_visits
);
232 fprintf(stderr
, _("%s: calls to Free_list::allocate: %u\n"),
233 program_name
, Free_list::num_allocates
);
234 fprintf(stderr
, _("%s: nodes visited: %u\n"),
235 program_name
, Free_list::num_allocate_visits
);
238 // Layout::Relaxation_debug_check methods.
240 // Check that sections and special data are in reset states.
241 // We do not save states for Output_sections and special Output_data.
242 // So we check that they have not assigned any addresses or offsets.
243 // clean_up_after_relaxation simply resets their addresses and offsets.
245 Layout::Relaxation_debug_check::check_output_data_for_reset_values(
246 const Layout::Section_list
& sections
,
247 const Layout::Data_list
& special_outputs
)
249 for(Layout::Section_list::const_iterator p
= sections
.begin();
252 gold_assert((*p
)->address_and_file_offset_have_reset_values());
254 for(Layout::Data_list::const_iterator p
= special_outputs
.begin();
255 p
!= special_outputs
.end();
257 gold_assert((*p
)->address_and_file_offset_have_reset_values());
260 // Save information of SECTIONS for checking later.
263 Layout::Relaxation_debug_check::read_sections(
264 const Layout::Section_list
& sections
)
266 for(Layout::Section_list::const_iterator p
= sections
.begin();
270 Output_section
* os
= *p
;
272 info
.output_section
= os
;
273 info
.address
= os
->is_address_valid() ? os
->address() : 0;
274 info
.data_size
= os
->is_data_size_valid() ? os
->data_size() : -1;
275 info
.offset
= os
->is_offset_valid()? os
->offset() : -1 ;
276 this->section_infos_
.push_back(info
);
280 // Verify SECTIONS using previously recorded information.
283 Layout::Relaxation_debug_check::verify_sections(
284 const Layout::Section_list
& sections
)
287 for(Layout::Section_list::const_iterator p
= sections
.begin();
291 Output_section
* os
= *p
;
292 uint64_t address
= os
->is_address_valid() ? os
->address() : 0;
293 off_t data_size
= os
->is_data_size_valid() ? os
->data_size() : -1;
294 off_t offset
= os
->is_offset_valid()? os
->offset() : -1 ;
296 if (i
>= this->section_infos_
.size())
298 gold_fatal("Section_info of %s missing.\n", os
->name());
300 const Section_info
& info
= this->section_infos_
[i
];
301 if (os
!= info
.output_section
)
302 gold_fatal("Section order changed. Expecting %s but see %s\n",
303 info
.output_section
->name(), os
->name());
304 if (address
!= info
.address
305 || data_size
!= info
.data_size
306 || offset
!= info
.offset
)
307 gold_fatal("Section %s changed.\n", os
->name());
311 // Layout_task_runner methods.
313 // Lay out the sections. This is called after all the input objects
317 Layout_task_runner::run(Workqueue
* workqueue
, const Task
* task
)
319 Layout
* layout
= this->layout_
;
320 off_t file_size
= layout
->finalize(this->input_objects_
,
325 // Now we know the final size of the output file and we know where
326 // each piece of information goes.
328 if (this->mapfile_
!= NULL
)
330 this->mapfile_
->print_discarded_sections(this->input_objects_
);
331 layout
->print_to_mapfile(this->mapfile_
);
335 if (layout
->incremental_base() == NULL
)
337 of
= new Output_file(parameters
->options().output_file_name());
338 if (this->options_
.oformat_enum() != General_options::OBJECT_FORMAT_ELF
)
339 of
->set_is_temporary();
344 of
= layout
->incremental_base()->output_file();
346 // Apply the incremental relocations for symbols whose values
347 // have changed. We do this before we resize the file and start
348 // writing anything else to it, so that we can read the old
349 // incremental information from the file before (possibly)
351 if (parameters
->incremental_update())
352 layout
->incremental_base()->apply_incremental_relocs(this->symtab_
,
356 of
->resize(file_size
);
359 // Queue up the final set of tasks.
360 gold::queue_final_tasks(this->options_
, this->input_objects_
,
361 this->symtab_
, layout
, workqueue
, of
);
366 Layout::Layout(int number_of_input_files
, Script_options
* script_options
)
367 : number_of_input_files_(number_of_input_files
),
368 script_options_(script_options
),
376 unattached_section_list_(),
377 special_output_list_(),
378 section_headers_(NULL
),
380 relro_segment_(NULL
),
381 interp_segment_(NULL
),
383 symtab_section_(NULL
),
384 symtab_xindex_(NULL
),
385 dynsym_section_(NULL
),
386 dynsym_xindex_(NULL
),
387 dynamic_section_(NULL
),
388 dynamic_symbol_(NULL
),
390 eh_frame_section_(NULL
),
391 eh_frame_data_(NULL
),
392 added_eh_frame_data_(false),
393 eh_frame_hdr_section_(NULL
),
394 gdb_index_data_(NULL
),
395 build_id_note_(NULL
),
399 output_file_size_(-1),
400 have_added_input_section_(false),
401 sections_are_attached_(false),
402 input_requires_executable_stack_(false),
403 input_with_gnu_stack_note_(false),
404 input_without_gnu_stack_note_(false),
405 has_static_tls_(false),
406 any_postprocessing_sections_(false),
407 resized_signatures_(false),
408 have_stabstr_section_(false),
409 section_ordering_specified_(false),
410 incremental_inputs_(NULL
),
411 record_output_section_data_from_script_(false),
412 script_output_section_data_list_(),
413 segment_states_(NULL
),
414 relaxation_debug_check_(NULL
),
415 section_order_map_(),
416 input_section_position_(),
417 input_section_glob_(),
418 incremental_base_(NULL
),
421 // Make space for more than enough segments for a typical file.
422 // This is just for efficiency--it's OK if we wind up needing more.
423 this->segment_list_
.reserve(12);
425 // We expect two unattached Output_data objects: the file header and
426 // the segment headers.
427 this->special_output_list_
.reserve(2);
429 // Initialize structure needed for an incremental build.
430 if (parameters
->incremental())
431 this->incremental_inputs_
= new Incremental_inputs
;
433 // The section name pool is worth optimizing in all cases, because
434 // it is small, but there are often overlaps due to .rel sections.
435 this->namepool_
.set_optimize();
438 // For incremental links, record the base file to be modified.
441 Layout::set_incremental_base(Incremental_binary
* base
)
443 this->incremental_base_
= base
;
444 this->free_list_
.init(base
->output_file()->filesize(), true);
447 // Hash a key we use to look up an output section mapping.
450 Layout::Hash_key::operator()(const Layout::Key
& k
) const
452 return k
.first
+ k
.second
.first
+ k
.second
.second
;
455 // Returns whether the given section is in the list of
456 // debug-sections-used-by-some-version-of-gdb. Currently,
457 // we've checked versions of gdb up to and including 6.7.1.
459 static const char* gdb_sections
[] =
461 // ".debug_aranges", // not used by gdb as of 6.7.1
468 // ".debug_pubnames", // not used by gdb as of 6.7.1
473 static const char* lines_only_debug_sections
[] =
475 // ".debug_aranges", // not used by gdb as of 6.7.1
482 // ".debug_pubnames", // not used by gdb as of 6.7.1
488 is_gdb_debug_section(const char* str
)
490 // We can do this faster: binary search or a hashtable. But why bother?
491 for (size_t i
= 0; i
< sizeof(gdb_sections
)/sizeof(*gdb_sections
); ++i
)
492 if (strcmp(str
, gdb_sections
[i
]) == 0)
498 is_lines_only_debug_section(const char* str
)
500 // We can do this faster: binary search or a hashtable. But why bother?
502 i
< sizeof(lines_only_debug_sections
)/sizeof(*lines_only_debug_sections
);
504 if (strcmp(str
, lines_only_debug_sections
[i
]) == 0)
509 // Sometimes we compress sections. This is typically done for
510 // sections that are not part of normal program execution (such as
511 // .debug_* sections), and where the readers of these sections know
512 // how to deal with compressed sections. This routine doesn't say for
513 // certain whether we'll compress -- it depends on commandline options
514 // as well -- just whether this section is a candidate for compression.
515 // (The Output_compressed_section class decides whether to compress
516 // a given section, and picks the name of the compressed section.)
519 is_compressible_debug_section(const char* secname
)
521 return (is_prefix_of(".debug", secname
));
524 // We may see compressed debug sections in input files. Return TRUE
525 // if this is the name of a compressed debug section.
528 is_compressed_debug_section(const char* secname
)
530 return (is_prefix_of(".zdebug", secname
));
533 // Whether to include this section in the link.
535 template<int size
, bool big_endian
>
537 Layout::include_section(Sized_relobj_file
<size
, big_endian
>*, const char* name
,
538 const elfcpp::Shdr
<size
, big_endian
>& shdr
)
540 if (shdr
.get_sh_flags() & elfcpp::SHF_EXCLUDE
)
543 switch (shdr
.get_sh_type())
545 case elfcpp::SHT_NULL
:
546 case elfcpp::SHT_SYMTAB
:
547 case elfcpp::SHT_DYNSYM
:
548 case elfcpp::SHT_HASH
:
549 case elfcpp::SHT_DYNAMIC
:
550 case elfcpp::SHT_SYMTAB_SHNDX
:
553 case elfcpp::SHT_STRTAB
:
554 // Discard the sections which have special meanings in the ELF
555 // ABI. Keep others (e.g., .stabstr). We could also do this by
556 // checking the sh_link fields of the appropriate sections.
557 return (strcmp(name
, ".dynstr") != 0
558 && strcmp(name
, ".strtab") != 0
559 && strcmp(name
, ".shstrtab") != 0);
561 case elfcpp::SHT_RELA
:
562 case elfcpp::SHT_REL
:
563 case elfcpp::SHT_GROUP
:
564 // If we are emitting relocations these should be handled
566 gold_assert(!parameters
->options().relocatable()
567 && !parameters
->options().emit_relocs());
570 case elfcpp::SHT_PROGBITS
:
571 if (parameters
->options().strip_debug()
572 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
574 if (is_debug_info_section(name
))
577 if (parameters
->options().strip_debug_non_line()
578 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
580 // Debugging sections can only be recognized by name.
581 if (is_prefix_of(".debug", name
)
582 && !is_lines_only_debug_section(name
))
585 if (parameters
->options().strip_debug_gdb()
586 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
588 // Debugging sections can only be recognized by name.
589 if (is_prefix_of(".debug", name
)
590 && !is_gdb_debug_section(name
))
593 if (parameters
->options().strip_lto_sections()
594 && !parameters
->options().relocatable()
595 && (shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) == 0)
597 // Ignore LTO sections containing intermediate code.
598 if (is_prefix_of(".gnu.lto_", name
))
601 // The GNU linker strips .gnu_debuglink sections, so we do too.
602 // This is a feature used to keep debugging information in
604 if (strcmp(name
, ".gnu_debuglink") == 0)
613 // Return an output section named NAME, or NULL if there is none.
616 Layout::find_output_section(const char* name
) const
618 for (Section_list::const_iterator p
= this->section_list_
.begin();
619 p
!= this->section_list_
.end();
621 if (strcmp((*p
)->name(), name
) == 0)
626 // Return an output segment of type TYPE, with segment flags SET set
627 // and segment flags CLEAR clear. Return NULL if there is none.
630 Layout::find_output_segment(elfcpp::PT type
, elfcpp::Elf_Word set
,
631 elfcpp::Elf_Word clear
) const
633 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
634 p
!= this->segment_list_
.end();
636 if (static_cast<elfcpp::PT
>((*p
)->type()) == type
637 && ((*p
)->flags() & set
) == set
638 && ((*p
)->flags() & clear
) == 0)
643 // When we put a .ctors or .dtors section with more than one word into
644 // a .init_array or .fini_array section, we need to reverse the words
645 // in the .ctors/.dtors section. This is because .init_array executes
646 // constructors front to back, where .ctors executes them back to
647 // front, and vice-versa for .fini_array/.dtors. Although we do want
648 // to remap .ctors/.dtors into .init_array/.fini_array because it can
649 // be more efficient, we don't want to change the order in which
650 // constructors/destructors are run. This set just keeps track of
651 // these sections which need to be reversed. It is only changed by
652 // Layout::layout. It should be a private member of Layout, but that
653 // would require layout.h to #include object.h to get the definition
655 static Unordered_set
<Section_id
, Section_id_hash
> ctors_sections_in_init_array
;
657 // Return whether OBJECT/SHNDX is a .ctors/.dtors section mapped to a
658 // .init_array/.fini_array section.
661 Layout::is_ctors_in_init_array(Relobj
* relobj
, unsigned int shndx
) const
663 return (ctors_sections_in_init_array
.find(Section_id(relobj
, shndx
))
664 != ctors_sections_in_init_array
.end());
667 // Return the output section to use for section NAME with type TYPE
668 // and section flags FLAGS. NAME must be canonicalized in the string
669 // pool, and NAME_KEY is the key. ORDER is where this should appear
670 // in the output sections. IS_RELRO is true for a relro section.
673 Layout::get_output_section(const char* name
, Stringpool::Key name_key
,
674 elfcpp::Elf_Word type
, elfcpp::Elf_Xword flags
,
675 Output_section_order order
, bool is_relro
)
677 elfcpp::Elf_Word lookup_type
= type
;
679 // For lookup purposes, treat INIT_ARRAY, FINI_ARRAY, and
680 // PREINIT_ARRAY like PROGBITS. This ensures that we combine
681 // .init_array, .fini_array, and .preinit_array sections by name
682 // whatever their type in the input file. We do this because the
683 // types are not always right in the input files.
684 if (lookup_type
== elfcpp::SHT_INIT_ARRAY
685 || lookup_type
== elfcpp::SHT_FINI_ARRAY
686 || lookup_type
== elfcpp::SHT_PREINIT_ARRAY
)
687 lookup_type
= elfcpp::SHT_PROGBITS
;
689 elfcpp::Elf_Xword lookup_flags
= flags
;
691 // Ignoring SHF_WRITE and SHF_EXECINSTR here means that we combine
692 // read-write with read-only sections. Some other ELF linkers do
693 // not do this. FIXME: Perhaps there should be an option
695 lookup_flags
&= ~(elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
);
697 const Key
key(name_key
, std::make_pair(lookup_type
, lookup_flags
));
698 const std::pair
<Key
, Output_section
*> v(key
, NULL
);
699 std::pair
<Section_name_map::iterator
, bool> ins(
700 this->section_name_map_
.insert(v
));
703 return ins
.first
->second
;
706 // This is the first time we've seen this name/type/flags
707 // combination. For compatibility with the GNU linker, we
708 // combine sections with contents and zero flags with sections
709 // with non-zero flags. This is a workaround for cases where
710 // assembler code forgets to set section flags. FIXME: Perhaps
711 // there should be an option to control this.
712 Output_section
* os
= NULL
;
714 if (lookup_type
== elfcpp::SHT_PROGBITS
)
718 Output_section
* same_name
= this->find_output_section(name
);
719 if (same_name
!= NULL
720 && (same_name
->type() == elfcpp::SHT_PROGBITS
721 || same_name
->type() == elfcpp::SHT_INIT_ARRAY
722 || same_name
->type() == elfcpp::SHT_FINI_ARRAY
723 || same_name
->type() == elfcpp::SHT_PREINIT_ARRAY
)
724 && (same_name
->flags() & elfcpp::SHF_TLS
) == 0)
727 else if ((flags
& elfcpp::SHF_TLS
) == 0)
729 elfcpp::Elf_Xword zero_flags
= 0;
730 const Key
zero_key(name_key
, std::make_pair(lookup_type
,
732 Section_name_map::iterator p
=
733 this->section_name_map_
.find(zero_key
);
734 if (p
!= this->section_name_map_
.end())
740 os
= this->make_output_section(name
, type
, flags
, order
, is_relro
);
742 ins
.first
->second
= os
;
747 // Pick the output section to use for section NAME, in input file
748 // RELOBJ, with type TYPE and flags FLAGS. RELOBJ may be NULL for a
749 // linker created section. IS_INPUT_SECTION is true if we are
750 // choosing an output section for an input section found in a input
751 // file. ORDER is where this section should appear in the output
752 // sections. IS_RELRO is true for a relro section. This will return
753 // NULL if the input section should be discarded.
756 Layout::choose_output_section(const Relobj
* relobj
, const char* name
,
757 elfcpp::Elf_Word type
, elfcpp::Elf_Xword flags
,
758 bool is_input_section
, Output_section_order order
,
761 // We should not see any input sections after we have attached
762 // sections to segments.
763 gold_assert(!is_input_section
|| !this->sections_are_attached_
);
765 // Some flags in the input section should not be automatically
766 // copied to the output section.
767 flags
&= ~ (elfcpp::SHF_INFO_LINK
770 | elfcpp::SHF_STRINGS
);
772 // We only clear the SHF_LINK_ORDER flag in for
773 // a non-relocatable link.
774 if (!parameters
->options().relocatable())
775 flags
&= ~elfcpp::SHF_LINK_ORDER
;
777 if (this->script_options_
->saw_sections_clause())
779 // We are using a SECTIONS clause, so the output section is
780 // chosen based only on the name.
782 Script_sections
* ss
= this->script_options_
->script_sections();
783 const char* file_name
= relobj
== NULL
? NULL
: relobj
->name().c_str();
784 Output_section
** output_section_slot
;
785 Script_sections::Section_type script_section_type
;
786 const char* orig_name
= name
;
787 name
= ss
->output_section_name(file_name
, name
, &output_section_slot
,
788 &script_section_type
);
791 gold_debug(DEBUG_SCRIPT
, _("Unable to create output section '%s' "
792 "because it is not allowed by the "
793 "SECTIONS clause of the linker script"),
795 // The SECTIONS clause says to discard this input section.
799 // We can only handle script section types ST_NONE and ST_NOLOAD.
800 switch (script_section_type
)
802 case Script_sections::ST_NONE
:
804 case Script_sections::ST_NOLOAD
:
805 flags
&= elfcpp::SHF_ALLOC
;
811 // If this is an orphan section--one not mentioned in the linker
812 // script--then OUTPUT_SECTION_SLOT will be NULL, and we do the
813 // default processing below.
815 if (output_section_slot
!= NULL
)
817 if (*output_section_slot
!= NULL
)
819 (*output_section_slot
)->update_flags_for_input_section(flags
);
820 return *output_section_slot
;
823 // We don't put sections found in the linker script into
824 // SECTION_NAME_MAP_. That keeps us from getting confused
825 // if an orphan section is mapped to a section with the same
826 // name as one in the linker script.
828 name
= this->namepool_
.add(name
, false, NULL
);
830 Output_section
* os
= this->make_output_section(name
, type
, flags
,
833 os
->set_found_in_sections_clause();
835 // Special handling for NOLOAD sections.
836 if (script_section_type
== Script_sections::ST_NOLOAD
)
840 // The constructor of Output_section sets addresses of non-ALLOC
841 // sections to 0 by default. We don't want that for NOLOAD
842 // sections even if they have no SHF_ALLOC flag.
843 if ((os
->flags() & elfcpp::SHF_ALLOC
) == 0
844 && os
->is_address_valid())
846 gold_assert(os
->address() == 0
847 && !os
->is_offset_valid()
848 && !os
->is_data_size_valid());
849 os
->reset_address_and_file_offset();
853 *output_section_slot
= os
;
858 // FIXME: Handle SHF_OS_NONCONFORMING somewhere.
860 size_t len
= strlen(name
);
861 char* uncompressed_name
= NULL
;
863 // Compressed debug sections should be mapped to the corresponding
864 // uncompressed section.
865 if (is_compressed_debug_section(name
))
867 uncompressed_name
= new char[len
];
868 uncompressed_name
[0] = '.';
869 gold_assert(name
[0] == '.' && name
[1] == 'z');
870 strncpy(&uncompressed_name
[1], &name
[2], len
- 2);
871 uncompressed_name
[len
- 1] = '\0';
873 name
= uncompressed_name
;
876 // Turn NAME from the name of the input section into the name of the
879 && !this->script_options_
->saw_sections_clause()
880 && !parameters
->options().relocatable())
881 name
= Layout::output_section_name(relobj
, name
, &len
);
883 Stringpool::Key name_key
;
884 name
= this->namepool_
.add_with_length(name
, len
, true, &name_key
);
886 if (uncompressed_name
!= NULL
)
887 delete[] uncompressed_name
;
889 // Find or make the output section. The output section is selected
890 // based on the section name, type, and flags.
891 return this->get_output_section(name
, name_key
, type
, flags
, order
, is_relro
);
894 // For incremental links, record the initial fixed layout of a section
895 // from the base file, and return a pointer to the Output_section.
897 template<int size
, bool big_endian
>
899 Layout::init_fixed_output_section(const char* name
,
900 elfcpp::Shdr
<size
, big_endian
>& shdr
)
902 unsigned int sh_type
= shdr
.get_sh_type();
904 // We preserve the layout of PROGBITS, NOBITS, INIT_ARRAY, FINI_ARRAY,
905 // PRE_INIT_ARRAY, and NOTE sections.
906 // All others will be created from scratch and reallocated.
907 if (!can_incremental_update(sh_type
))
910 // If we're generating a .gdb_index section, we need to regenerate
912 if (parameters
->options().gdb_index()
913 && sh_type
== elfcpp::SHT_PROGBITS
914 && strcmp(name
, ".gdb_index") == 0)
917 typename
elfcpp::Elf_types
<size
>::Elf_Addr sh_addr
= shdr
.get_sh_addr();
918 typename
elfcpp::Elf_types
<size
>::Elf_Off sh_offset
= shdr
.get_sh_offset();
919 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_size
= shdr
.get_sh_size();
920 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_flags
= shdr
.get_sh_flags();
921 typename
elfcpp::Elf_types
<size
>::Elf_WXword sh_addralign
=
922 shdr
.get_sh_addralign();
924 // Make the output section.
925 Stringpool::Key name_key
;
926 name
= this->namepool_
.add(name
, true, &name_key
);
927 Output_section
* os
= this->get_output_section(name
, name_key
, sh_type
,
928 sh_flags
, ORDER_INVALID
, false);
929 os
->set_fixed_layout(sh_addr
, sh_offset
, sh_size
, sh_addralign
);
930 if (sh_type
!= elfcpp::SHT_NOBITS
)
931 this->free_list_
.remove(sh_offset
, sh_offset
+ sh_size
);
935 // Return the output section to use for input section SHNDX, with name
936 // NAME, with header HEADER, from object OBJECT. RELOC_SHNDX is the
937 // index of a relocation section which applies to this section, or 0
938 // if none, or -1U if more than one. RELOC_TYPE is the type of the
939 // relocation section if there is one. Set *OFF to the offset of this
940 // input section without the output section. Return NULL if the
941 // section should be discarded. Set *OFF to -1 if the section
942 // contents should not be written directly to the output file, but
943 // will instead receive special handling.
945 template<int size
, bool big_endian
>
947 Layout::layout(Sized_relobj_file
<size
, big_endian
>* object
, unsigned int shndx
,
948 const char* name
, const elfcpp::Shdr
<size
, big_endian
>& shdr
,
949 unsigned int reloc_shndx
, unsigned int, off_t
* off
)
953 if (!this->include_section(object
, name
, shdr
))
956 elfcpp::Elf_Word sh_type
= shdr
.get_sh_type();
958 // In a relocatable link a grouped section must not be combined with
959 // any other sections.
961 if (parameters
->options().relocatable()
962 && (shdr
.get_sh_flags() & elfcpp::SHF_GROUP
) != 0)
964 name
= this->namepool_
.add(name
, true, NULL
);
965 os
= this->make_output_section(name
, sh_type
, shdr
.get_sh_flags(),
966 ORDER_INVALID
, false);
970 os
= this->choose_output_section(object
, name
, sh_type
,
971 shdr
.get_sh_flags(), true,
972 ORDER_INVALID
, false);
977 // By default the GNU linker sorts input sections whose names match
978 // .ctors.*, .dtors.*, .init_array.*, or .fini_array.*. The
979 // sections are sorted by name. This is used to implement
980 // constructor priority ordering. We are compatible. When we put
981 // .ctor sections in .init_array and .dtor sections in .fini_array,
982 // we must also sort plain .ctor and .dtor sections.
983 if (!this->script_options_
->saw_sections_clause()
984 && !parameters
->options().relocatable()
985 && (is_prefix_of(".ctors.", name
)
986 || is_prefix_of(".dtors.", name
)
987 || is_prefix_of(".init_array.", name
)
988 || is_prefix_of(".fini_array.", name
)
989 || (parameters
->options().ctors_in_init_array()
990 && (strcmp(name
, ".ctors") == 0
991 || strcmp(name
, ".dtors") == 0))))
992 os
->set_must_sort_attached_input_sections();
994 // If this is a .ctors or .ctors.* section being mapped to a
995 // .init_array section, or a .dtors or .dtors.* section being mapped
996 // to a .fini_array section, we will need to reverse the words if
997 // there is more than one. Record this section for later. See
998 // ctors_sections_in_init_array above.
999 if (!this->script_options_
->saw_sections_clause()
1000 && !parameters
->options().relocatable()
1001 && shdr
.get_sh_size() > size
/ 8
1002 && (((strcmp(name
, ".ctors") == 0
1003 || is_prefix_of(".ctors.", name
))
1004 && strcmp(os
->name(), ".init_array") == 0)
1005 || ((strcmp(name
, ".dtors") == 0
1006 || is_prefix_of(".dtors.", name
))
1007 && strcmp(os
->name(), ".fini_array") == 0)))
1008 ctors_sections_in_init_array
.insert(Section_id(object
, shndx
));
1010 // FIXME: Handle SHF_LINK_ORDER somewhere.
1012 elfcpp::Elf_Xword orig_flags
= os
->flags();
1014 *off
= os
->add_input_section(this, object
, shndx
, name
, shdr
, reloc_shndx
,
1015 this->script_options_
->saw_sections_clause());
1017 // If the flags changed, we may have to change the order.
1018 if ((orig_flags
& elfcpp::SHF_ALLOC
) != 0)
1020 orig_flags
&= (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
);
1021 elfcpp::Elf_Xword new_flags
=
1022 os
->flags() & (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
);
1023 if (orig_flags
!= new_flags
)
1024 os
->set_order(this->default_section_order(os
, false));
1027 this->have_added_input_section_
= true;
1032 // Handle a relocation section when doing a relocatable link.
1034 template<int size
, bool big_endian
>
1036 Layout::layout_reloc(Sized_relobj_file
<size
, big_endian
>* object
,
1038 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1039 Output_section
* data_section
,
1040 Relocatable_relocs
* rr
)
1042 gold_assert(parameters
->options().relocatable()
1043 || parameters
->options().emit_relocs());
1045 int sh_type
= shdr
.get_sh_type();
1048 if (sh_type
== elfcpp::SHT_REL
)
1050 else if (sh_type
== elfcpp::SHT_RELA
)
1054 name
+= data_section
->name();
1056 // In a relocatable link relocs for a grouped section must not be
1057 // combined with other reloc sections.
1059 if (!parameters
->options().relocatable()
1060 || (data_section
->flags() & elfcpp::SHF_GROUP
) == 0)
1061 os
= this->choose_output_section(object
, name
.c_str(), sh_type
,
1062 shdr
.get_sh_flags(), false,
1063 ORDER_INVALID
, false);
1066 const char* n
= this->namepool_
.add(name
.c_str(), true, NULL
);
1067 os
= this->make_output_section(n
, sh_type
, shdr
.get_sh_flags(),
1068 ORDER_INVALID
, false);
1071 os
->set_should_link_to_symtab();
1072 os
->set_info_section(data_section
);
1074 Output_section_data
* posd
;
1075 if (sh_type
== elfcpp::SHT_REL
)
1077 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rel_size
);
1078 posd
= new Output_relocatable_relocs
<elfcpp::SHT_REL
,
1082 else if (sh_type
== elfcpp::SHT_RELA
)
1084 os
->set_entsize(elfcpp::Elf_sizes
<size
>::rela_size
);
1085 posd
= new Output_relocatable_relocs
<elfcpp::SHT_RELA
,
1092 os
->add_output_section_data(posd
);
1093 rr
->set_output_data(posd
);
1098 // Handle a group section when doing a relocatable link.
1100 template<int size
, bool big_endian
>
1102 Layout::layout_group(Symbol_table
* symtab
,
1103 Sized_relobj_file
<size
, big_endian
>* object
,
1105 const char* group_section_name
,
1106 const char* signature
,
1107 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1108 elfcpp::Elf_Word flags
,
1109 std::vector
<unsigned int>* shndxes
)
1111 gold_assert(parameters
->options().relocatable());
1112 gold_assert(shdr
.get_sh_type() == elfcpp::SHT_GROUP
);
1113 group_section_name
= this->namepool_
.add(group_section_name
, true, NULL
);
1114 Output_section
* os
= this->make_output_section(group_section_name
,
1116 shdr
.get_sh_flags(),
1117 ORDER_INVALID
, false);
1119 // We need to find a symbol with the signature in the symbol table.
1120 // If we don't find one now, we need to look again later.
1121 Symbol
* sym
= symtab
->lookup(signature
, NULL
);
1123 os
->set_info_symndx(sym
);
1126 // Reserve some space to minimize reallocations.
1127 if (this->group_signatures_
.empty())
1128 this->group_signatures_
.reserve(this->number_of_input_files_
* 16);
1130 // We will wind up using a symbol whose name is the signature.
1131 // So just put the signature in the symbol name pool to save it.
1132 signature
= symtab
->canonicalize_name(signature
);
1133 this->group_signatures_
.push_back(Group_signature(os
, signature
));
1136 os
->set_should_link_to_symtab();
1139 section_size_type entry_count
=
1140 convert_to_section_size_type(shdr
.get_sh_size() / 4);
1141 Output_section_data
* posd
=
1142 new Output_data_group
<size
, big_endian
>(object
, entry_count
, flags
,
1144 os
->add_output_section_data(posd
);
1147 // Special GNU handling of sections name .eh_frame. They will
1148 // normally hold exception frame data as defined by the C++ ABI
1149 // (http://codesourcery.com/cxx-abi/).
1151 template<int size
, bool big_endian
>
1153 Layout::layout_eh_frame(Sized_relobj_file
<size
, big_endian
>* object
,
1154 const unsigned char* symbols
,
1156 const unsigned char* symbol_names
,
1157 off_t symbol_names_size
,
1159 const elfcpp::Shdr
<size
, big_endian
>& shdr
,
1160 unsigned int reloc_shndx
, unsigned int reloc_type
,
1163 gold_assert(shdr
.get_sh_type() == elfcpp::SHT_PROGBITS
1164 || shdr
.get_sh_type() == elfcpp::SHT_X86_64_UNWIND
);
1165 gold_assert((shdr
.get_sh_flags() & elfcpp::SHF_ALLOC
) != 0);
1167 Output_section
* os
= this->make_eh_frame_section(object
);
1171 gold_assert(this->eh_frame_section_
== os
);
1173 elfcpp::Elf_Xword orig_flags
= os
->flags();
1175 if (!parameters
->incremental()
1176 && this->eh_frame_data_
->add_ehframe_input_section(object
,
1185 os
->update_flags_for_input_section(shdr
.get_sh_flags());
1187 // A writable .eh_frame section is a RELRO section.
1188 if ((orig_flags
& (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
))
1189 != (os
->flags() & (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
)))
1192 os
->set_order(ORDER_RELRO
);
1195 // We found a .eh_frame section we are going to optimize, so now
1196 // we can add the set of optimized sections to the output
1197 // section. We need to postpone adding this until we've found a
1198 // section we can optimize so that the .eh_frame section in
1199 // crtbegin.o winds up at the start of the output section.
1200 if (!this->added_eh_frame_data_
)
1202 os
->add_output_section_data(this->eh_frame_data_
);
1203 this->added_eh_frame_data_
= true;
1209 // We couldn't handle this .eh_frame section for some reason.
1210 // Add it as a normal section.
1211 bool saw_sections_clause
= this->script_options_
->saw_sections_clause();
1212 *off
= os
->add_input_section(this, object
, shndx
, ".eh_frame", shdr
,
1213 reloc_shndx
, saw_sections_clause
);
1214 this->have_added_input_section_
= true;
1216 if ((orig_flags
& (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
))
1217 != (os
->flags() & (elfcpp::SHF_WRITE
| elfcpp::SHF_EXECINSTR
)))
1218 os
->set_order(this->default_section_order(os
, false));
1224 // Create and return the magic .eh_frame section. Create
1225 // .eh_frame_hdr also if appropriate. OBJECT is the object with the
1226 // input .eh_frame section; it may be NULL.
1229 Layout::make_eh_frame_section(const Relobj
* object
)
1231 // FIXME: On x86_64, this could use SHT_X86_64_UNWIND rather than
1233 Output_section
* os
= this->choose_output_section(object
, ".eh_frame",
1234 elfcpp::SHT_PROGBITS
,
1235 elfcpp::SHF_ALLOC
, false,
1236 ORDER_EHFRAME
, false);
1240 if (this->eh_frame_section_
== NULL
)
1242 this->eh_frame_section_
= os
;
1243 this->eh_frame_data_
= new Eh_frame();
1245 // For incremental linking, we do not optimize .eh_frame sections
1246 // or create a .eh_frame_hdr section.
1247 if (parameters
->options().eh_frame_hdr() && !parameters
->incremental())
1249 Output_section
* hdr_os
=
1250 this->choose_output_section(NULL
, ".eh_frame_hdr",
1251 elfcpp::SHT_PROGBITS
,
1252 elfcpp::SHF_ALLOC
, false,
1253 ORDER_EHFRAME
, false);
1257 Eh_frame_hdr
* hdr_posd
= new Eh_frame_hdr(os
,
1258 this->eh_frame_data_
);
1259 hdr_os
->add_output_section_data(hdr_posd
);
1261 hdr_os
->set_after_input_sections();
1263 if (!this->script_options_
->saw_phdrs_clause())
1265 Output_segment
* hdr_oseg
;
1266 hdr_oseg
= this->make_output_segment(elfcpp::PT_GNU_EH_FRAME
,
1268 hdr_oseg
->add_output_section_to_nonload(hdr_os
,
1272 this->eh_frame_data_
->set_eh_frame_hdr(hdr_posd
);
1280 // Add an exception frame for a PLT. This is called from target code.
1283 Layout::add_eh_frame_for_plt(Output_data
* plt
, const unsigned char* cie_data
,
1284 size_t cie_length
, const unsigned char* fde_data
,
1287 if (parameters
->incremental())
1289 // FIXME: Maybe this could work some day....
1292 Output_section
* os
= this->make_eh_frame_section(NULL
);
1295 this->eh_frame_data_
->add_ehframe_for_plt(plt
, cie_data
, cie_length
,
1296 fde_data
, fde_length
);
1297 if (!this->added_eh_frame_data_
)
1299 os
->add_output_section_data(this->eh_frame_data_
);
1300 this->added_eh_frame_data_
= true;
1304 // Scan a .debug_info or .debug_types section, and add summary
1305 // information to the .gdb_index section.
1307 template<int size
, bool big_endian
>
1309 Layout::add_to_gdb_index(bool is_type_unit
,
1310 Sized_relobj
<size
, big_endian
>* object
,
1311 const unsigned char* symbols
,
1314 unsigned int reloc_shndx
,
1315 unsigned int reloc_type
)
1317 if (this->gdb_index_data_
== NULL
)
1319 Output_section
* os
= this->choose_output_section(NULL
, ".gdb_index",
1320 elfcpp::SHT_PROGBITS
, 0,
1321 false, ORDER_INVALID
,
1326 this->gdb_index_data_
= new Gdb_index(os
);
1327 os
->add_output_section_data(this->gdb_index_data_
);
1328 os
->set_after_input_sections();
1331 this->gdb_index_data_
->scan_debug_info(is_type_unit
, object
, symbols
,
1332 symbols_size
, shndx
, reloc_shndx
,
1336 // Add POSD to an output section using NAME, TYPE, and FLAGS. Return
1337 // the output section.
1340 Layout::add_output_section_data(const char* name
, elfcpp::Elf_Word type
,
1341 elfcpp::Elf_Xword flags
,
1342 Output_section_data
* posd
,
1343 Output_section_order order
, bool is_relro
)
1345 Output_section
* os
= this->choose_output_section(NULL
, name
, type
, flags
,
1346 false, order
, is_relro
);
1348 os
->add_output_section_data(posd
);
1352 // Map section flags to segment flags.
1355 Layout::section_flags_to_segment(elfcpp::Elf_Xword flags
)
1357 elfcpp::Elf_Word ret
= elfcpp::PF_R
;
1358 if ((flags
& elfcpp::SHF_WRITE
) != 0)
1359 ret
|= elfcpp::PF_W
;
1360 if ((flags
& elfcpp::SHF_EXECINSTR
) != 0)
1361 ret
|= elfcpp::PF_X
;
1365 // Make a new Output_section, and attach it to segments as
1366 // appropriate. ORDER is the order in which this section should
1367 // appear in the output segment. IS_RELRO is true if this is a relro
1368 // (read-only after relocations) section.
1371 Layout::make_output_section(const char* name
, elfcpp::Elf_Word type
,
1372 elfcpp::Elf_Xword flags
,
1373 Output_section_order order
, bool is_relro
)
1376 if ((flags
& elfcpp::SHF_ALLOC
) == 0
1377 && strcmp(parameters
->options().compress_debug_sections(), "none") != 0
1378 && is_compressible_debug_section(name
))
1379 os
= new Output_compressed_section(¶meters
->options(), name
, type
,
1381 else if ((flags
& elfcpp::SHF_ALLOC
) == 0
1382 && parameters
->options().strip_debug_non_line()
1383 && strcmp(".debug_abbrev", name
) == 0)
1385 os
= this->debug_abbrev_
= new Output_reduced_debug_abbrev_section(
1387 if (this->debug_info_
)
1388 this->debug_info_
->set_abbreviations(this->debug_abbrev_
);
1390 else if ((flags
& elfcpp::SHF_ALLOC
) == 0
1391 && parameters
->options().strip_debug_non_line()
1392 && strcmp(".debug_info", name
) == 0)
1394 os
= this->debug_info_
= new Output_reduced_debug_info_section(
1396 if (this->debug_abbrev_
)
1397 this->debug_info_
->set_abbreviations(this->debug_abbrev_
);
1401 // Sometimes .init_array*, .preinit_array* and .fini_array* do
1402 // not have correct section types. Force them here.
1403 if (type
== elfcpp::SHT_PROGBITS
)
1405 if (is_prefix_of(".init_array", name
))
1406 type
= elfcpp::SHT_INIT_ARRAY
;
1407 else if (is_prefix_of(".preinit_array", name
))
1408 type
= elfcpp::SHT_PREINIT_ARRAY
;
1409 else if (is_prefix_of(".fini_array", name
))
1410 type
= elfcpp::SHT_FINI_ARRAY
;
1413 // FIXME: const_cast is ugly.
1414 Target
* target
= const_cast<Target
*>(¶meters
->target());
1415 os
= target
->make_output_section(name
, type
, flags
);
1418 // With -z relro, we have to recognize the special sections by name.
1419 // There is no other way.
1420 bool is_relro_local
= false;
1421 if (!this->script_options_
->saw_sections_clause()
1422 && parameters
->options().relro()
1423 && (flags
& elfcpp::SHF_ALLOC
) != 0
1424 && (flags
& elfcpp::SHF_WRITE
) != 0)
1426 if (type
== elfcpp::SHT_PROGBITS
)
1428 if (strcmp(name
, ".data.rel.ro") == 0)
1430 else if (strcmp(name
, ".data.rel.ro.local") == 0)
1433 is_relro_local
= true;
1435 else if (strcmp(name
, ".ctors") == 0
1436 || strcmp(name
, ".dtors") == 0
1437 || strcmp(name
, ".jcr") == 0)
1440 else if (type
== elfcpp::SHT_INIT_ARRAY
1441 || type
== elfcpp::SHT_FINI_ARRAY
1442 || type
== elfcpp::SHT_PREINIT_ARRAY
)
1449 if (order
== ORDER_INVALID
&& (flags
& elfcpp::SHF_ALLOC
) != 0)
1450 order
= this->default_section_order(os
, is_relro_local
);
1452 os
->set_order(order
);
1454 parameters
->target().new_output_section(os
);
1456 this->section_list_
.push_back(os
);
1458 // The GNU linker by default sorts some sections by priority, so we
1459 // do the same. We need to know that this might happen before we
1460 // attach any input sections.
1461 if (!this->script_options_
->saw_sections_clause()
1462 && !parameters
->options().relocatable()
1463 && (strcmp(name
, ".init_array") == 0
1464 || strcmp(name
, ".fini_array") == 0
1465 || (!parameters
->options().ctors_in_init_array()
1466 && (strcmp(name
, ".ctors") == 0
1467 || strcmp(name
, ".dtors") == 0))))
1468 os
->set_may_sort_attached_input_sections();
1470 // Check for .stab*str sections, as .stab* sections need to link to
1472 if (type
== elfcpp::SHT_STRTAB
1473 && !this->have_stabstr_section_
1474 && strncmp(name
, ".stab", 5) == 0
1475 && strcmp(name
+ strlen(name
) - 3, "str") == 0)
1476 this->have_stabstr_section_
= true;
1478 // During a full incremental link, we add patch space to most
1479 // PROGBITS and NOBITS sections. Flag those that may be
1480 // arbitrarily padded.
1481 if ((type
== elfcpp::SHT_PROGBITS
|| type
== elfcpp::SHT_NOBITS
)
1482 && order
!= ORDER_INTERP
1483 && order
!= ORDER_INIT
1484 && order
!= ORDER_PLT
1485 && order
!= ORDER_FINI
1486 && order
!= ORDER_RELRO_LAST
1487 && order
!= ORDER_NON_RELRO_FIRST
1488 && strcmp(name
, ".eh_frame") != 0
1489 && strcmp(name
, ".ctors") != 0
1490 && strcmp(name
, ".dtors") != 0
1491 && strcmp(name
, ".jcr") != 0)
1493 os
->set_is_patch_space_allowed();
1495 // Certain sections require "holes" to be filled with
1496 // specific fill patterns. These fill patterns may have
1497 // a minimum size, so we must prevent allocations from the
1498 // free list that leave a hole smaller than the minimum.
1499 if (strcmp(name
, ".debug_info") == 0)
1500 os
->set_free_space_fill(new Output_fill_debug_info(false));
1501 else if (strcmp(name
, ".debug_types") == 0)
1502 os
->set_free_space_fill(new Output_fill_debug_info(true));
1503 else if (strcmp(name
, ".debug_line") == 0)
1504 os
->set_free_space_fill(new Output_fill_debug_line());
1507 // If we have already attached the sections to segments, then we
1508 // need to attach this one now. This happens for sections created
1509 // directly by the linker.
1510 if (this->sections_are_attached_
)
1511 this->attach_section_to_segment(os
);
1516 // Return the default order in which a section should be placed in an
1517 // output segment. This function captures a lot of the ideas in
1518 // ld/scripttempl/elf.sc in the GNU linker. Note that the order of a
1519 // linker created section is normally set when the section is created;
1520 // this function is used for input sections.
1522 Output_section_order
1523 Layout::default_section_order(Output_section
* os
, bool is_relro_local
)
1525 gold_assert((os
->flags() & elfcpp::SHF_ALLOC
) != 0);
1526 bool is_write
= (os
->flags() & elfcpp::SHF_WRITE
) != 0;
1527 bool is_execinstr
= (os
->flags() & elfcpp::SHF_EXECINSTR
) != 0;
1528 bool is_bss
= false;
1533 case elfcpp::SHT_PROGBITS
:
1535 case elfcpp::SHT_NOBITS
:
1538 case elfcpp::SHT_RELA
:
1539 case elfcpp::SHT_REL
:
1541 return ORDER_DYNAMIC_RELOCS
;
1543 case elfcpp::SHT_HASH
:
1544 case elfcpp::SHT_DYNAMIC
:
1545 case elfcpp::SHT_SHLIB
:
1546 case elfcpp::SHT_DYNSYM
:
1547 case elfcpp::SHT_GNU_HASH
:
1548 case elfcpp::SHT_GNU_verdef
:
1549 case elfcpp::SHT_GNU_verneed
:
1550 case elfcpp::SHT_GNU_versym
:
1552 return ORDER_DYNAMIC_LINKER
;
1554 case elfcpp::SHT_NOTE
:
1555 return is_write
? ORDER_RW_NOTE
: ORDER_RO_NOTE
;
1558 if ((os
->flags() & elfcpp::SHF_TLS
) != 0)
1559 return is_bss
? ORDER_TLS_BSS
: ORDER_TLS_DATA
;
1561 if (!is_bss
&& !is_write
)
1565 if (strcmp(os
->name(), ".init") == 0)
1567 else if (strcmp(os
->name(), ".fini") == 0)
1570 return is_execinstr
? ORDER_TEXT
: ORDER_READONLY
;
1574 return is_relro_local
? ORDER_RELRO_LOCAL
: ORDER_RELRO
;
1576 if (os
->is_small_section())
1577 return is_bss
? ORDER_SMALL_BSS
: ORDER_SMALL_DATA
;
1578 if (os
->is_large_section())
1579 return is_bss
? ORDER_LARGE_BSS
: ORDER_LARGE_DATA
;
1581 return is_bss
? ORDER_BSS
: ORDER_DATA
;
1584 // Attach output sections to segments. This is called after we have
1585 // seen all the input sections.
1588 Layout::attach_sections_to_segments()
1590 for (Section_list::iterator p
= this->section_list_
.begin();
1591 p
!= this->section_list_
.end();
1593 this->attach_section_to_segment(*p
);
1595 this->sections_are_attached_
= true;
1598 // Attach an output section to a segment.
1601 Layout::attach_section_to_segment(Output_section
* os
)
1603 if ((os
->flags() & elfcpp::SHF_ALLOC
) == 0)
1604 this->unattached_section_list_
.push_back(os
);
1606 this->attach_allocated_section_to_segment(os
);
1609 // Attach an allocated output section to a segment.
1612 Layout::attach_allocated_section_to_segment(Output_section
* os
)
1614 elfcpp::Elf_Xword flags
= os
->flags();
1615 gold_assert((flags
& elfcpp::SHF_ALLOC
) != 0);
1617 if (parameters
->options().relocatable())
1620 // If we have a SECTIONS clause, we can't handle the attachment to
1621 // segments until after we've seen all the sections.
1622 if (this->script_options_
->saw_sections_clause())
1625 gold_assert(!this->script_options_
->saw_phdrs_clause());
1627 // This output section goes into a PT_LOAD segment.
1629 elfcpp::Elf_Word seg_flags
= Layout::section_flags_to_segment(flags
);
1631 // Check for --section-start.
1633 bool is_address_set
= parameters
->options().section_start(os
->name(), &addr
);
1635 // In general the only thing we really care about for PT_LOAD
1636 // segments is whether or not they are writable or executable,
1637 // so that is how we search for them.
1638 // Large data sections also go into their own PT_LOAD segment.
1639 // People who need segments sorted on some other basis will
1640 // have to use a linker script.
1642 Segment_list::const_iterator p
;
1643 for (p
= this->segment_list_
.begin();
1644 p
!= this->segment_list_
.end();
1647 if ((*p
)->type() != elfcpp::PT_LOAD
)
1649 if (!parameters
->options().omagic()
1650 && ((*p
)->flags() & elfcpp::PF_W
) != (seg_flags
& elfcpp::PF_W
))
1652 if (parameters
->options().rosegment()
1653 && ((*p
)->flags() & elfcpp::PF_X
) != (seg_flags
& elfcpp::PF_X
))
1655 // If -Tbss was specified, we need to separate the data and BSS
1657 if (parameters
->options().user_set_Tbss())
1659 if ((os
->type() == elfcpp::SHT_NOBITS
)
1660 == (*p
)->has_any_data_sections())
1663 if (os
->is_large_data_section() && !(*p
)->is_large_data_segment())
1668 if ((*p
)->are_addresses_set())
1671 (*p
)->add_initial_output_data(os
);
1672 (*p
)->update_flags_for_output_section(seg_flags
);
1673 (*p
)->set_addresses(addr
, addr
);
1677 (*p
)->add_output_section_to_load(this, os
, seg_flags
);
1681 if (p
== this->segment_list_
.end())
1683 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_LOAD
,
1685 if (os
->is_large_data_section())
1686 oseg
->set_is_large_data_segment();
1687 oseg
->add_output_section_to_load(this, os
, seg_flags
);
1689 oseg
->set_addresses(addr
, addr
);
1692 // If we see a loadable SHT_NOTE section, we create a PT_NOTE
1694 if (os
->type() == elfcpp::SHT_NOTE
)
1696 // See if we already have an equivalent PT_NOTE segment.
1697 for (p
= this->segment_list_
.begin();
1698 p
!= segment_list_
.end();
1701 if ((*p
)->type() == elfcpp::PT_NOTE
1702 && (((*p
)->flags() & elfcpp::PF_W
)
1703 == (seg_flags
& elfcpp::PF_W
)))
1705 (*p
)->add_output_section_to_nonload(os
, seg_flags
);
1710 if (p
== this->segment_list_
.end())
1712 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_NOTE
,
1714 oseg
->add_output_section_to_nonload(os
, seg_flags
);
1718 // If we see a loadable SHF_TLS section, we create a PT_TLS
1719 // segment. There can only be one such segment.
1720 if ((flags
& elfcpp::SHF_TLS
) != 0)
1722 if (this->tls_segment_
== NULL
)
1723 this->make_output_segment(elfcpp::PT_TLS
, seg_flags
);
1724 this->tls_segment_
->add_output_section_to_nonload(os
, seg_flags
);
1727 // If -z relro is in effect, and we see a relro section, we create a
1728 // PT_GNU_RELRO segment. There can only be one such segment.
1729 if (os
->is_relro() && parameters
->options().relro())
1731 gold_assert(seg_flags
== (elfcpp::PF_R
| elfcpp::PF_W
));
1732 if (this->relro_segment_
== NULL
)
1733 this->make_output_segment(elfcpp::PT_GNU_RELRO
, seg_flags
);
1734 this->relro_segment_
->add_output_section_to_nonload(os
, seg_flags
);
1737 // If we see a section named .interp, put it into a PT_INTERP
1738 // segment. This seems broken to me, but this is what GNU ld does,
1739 // and glibc expects it.
1740 if (strcmp(os
->name(), ".interp") == 0
1741 && !this->script_options_
->saw_phdrs_clause())
1743 if (this->interp_segment_
== NULL
)
1744 this->make_output_segment(elfcpp::PT_INTERP
, seg_flags
);
1746 gold_warning(_("multiple '.interp' sections in input files "
1747 "may cause confusing PT_INTERP segment"));
1748 this->interp_segment_
->add_output_section_to_nonload(os
, seg_flags
);
1752 // Make an output section for a script.
1755 Layout::make_output_section_for_script(
1757 Script_sections::Section_type section_type
)
1759 name
= this->namepool_
.add(name
, false, NULL
);
1760 elfcpp::Elf_Xword sh_flags
= elfcpp::SHF_ALLOC
;
1761 if (section_type
== Script_sections::ST_NOLOAD
)
1763 Output_section
* os
= this->make_output_section(name
, elfcpp::SHT_PROGBITS
,
1764 sh_flags
, ORDER_INVALID
,
1766 os
->set_found_in_sections_clause();
1767 if (section_type
== Script_sections::ST_NOLOAD
)
1768 os
->set_is_noload();
1772 // Return the number of segments we expect to see.
1775 Layout::expected_segment_count() const
1777 size_t ret
= this->segment_list_
.size();
1779 // If we didn't see a SECTIONS clause in a linker script, we should
1780 // already have the complete list of segments. Otherwise we ask the
1781 // SECTIONS clause how many segments it expects, and add in the ones
1782 // we already have (PT_GNU_STACK, PT_GNU_EH_FRAME, etc.)
1784 if (!this->script_options_
->saw_sections_clause())
1788 const Script_sections
* ss
= this->script_options_
->script_sections();
1789 return ret
+ ss
->expected_segment_count(this);
1793 // Handle the .note.GNU-stack section at layout time. SEEN_GNU_STACK
1794 // is whether we saw a .note.GNU-stack section in the object file.
1795 // GNU_STACK_FLAGS is the section flags. The flags give the
1796 // protection required for stack memory. We record this in an
1797 // executable as a PT_GNU_STACK segment. If an object file does not
1798 // have a .note.GNU-stack segment, we must assume that it is an old
1799 // object. On some targets that will force an executable stack.
1802 Layout::layout_gnu_stack(bool seen_gnu_stack
, uint64_t gnu_stack_flags
,
1805 if (!seen_gnu_stack
)
1807 this->input_without_gnu_stack_note_
= true;
1808 if (parameters
->options().warn_execstack()
1809 && parameters
->target().is_default_stack_executable())
1810 gold_warning(_("%s: missing .note.GNU-stack section"
1811 " implies executable stack"),
1812 obj
->name().c_str());
1816 this->input_with_gnu_stack_note_
= true;
1817 if ((gnu_stack_flags
& elfcpp::SHF_EXECINSTR
) != 0)
1819 this->input_requires_executable_stack_
= true;
1820 if (parameters
->options().warn_execstack()
1821 || parameters
->options().is_stack_executable())
1822 gold_warning(_("%s: requires executable stack"),
1823 obj
->name().c_str());
1828 // Create automatic note sections.
1831 Layout::create_notes()
1833 this->create_gold_note();
1834 this->create_executable_stack_info();
1835 this->create_build_id();
1838 // Create the dynamic sections which are needed before we read the
1842 Layout::create_initial_dynamic_sections(Symbol_table
* symtab
)
1844 if (parameters
->doing_static_link())
1847 this->dynamic_section_
= this->choose_output_section(NULL
, ".dynamic",
1848 elfcpp::SHT_DYNAMIC
,
1850 | elfcpp::SHF_WRITE
),
1854 // A linker script may discard .dynamic, so check for NULL.
1855 if (this->dynamic_section_
!= NULL
)
1857 this->dynamic_symbol_
=
1858 symtab
->define_in_output_data("_DYNAMIC", NULL
,
1859 Symbol_table::PREDEFINED
,
1860 this->dynamic_section_
, 0, 0,
1861 elfcpp::STT_OBJECT
, elfcpp::STB_LOCAL
,
1862 elfcpp::STV_HIDDEN
, 0, false, false);
1864 this->dynamic_data_
= new Output_data_dynamic(&this->dynpool_
);
1866 this->dynamic_section_
->add_output_section_data(this->dynamic_data_
);
1870 // For each output section whose name can be represented as C symbol,
1871 // define __start and __stop symbols for the section. This is a GNU
1875 Layout::define_section_symbols(Symbol_table
* symtab
)
1877 for (Section_list::const_iterator p
= this->section_list_
.begin();
1878 p
!= this->section_list_
.end();
1881 const char* const name
= (*p
)->name();
1882 if (is_cident(name
))
1884 const std::string
name_string(name
);
1885 const std::string
start_name(cident_section_start_prefix
1887 const std::string
stop_name(cident_section_stop_prefix
1890 symtab
->define_in_output_data(start_name
.c_str(),
1892 Symbol_table::PREDEFINED
,
1898 elfcpp::STV_DEFAULT
,
1900 false, // offset_is_from_end
1901 true); // only_if_ref
1903 symtab
->define_in_output_data(stop_name
.c_str(),
1905 Symbol_table::PREDEFINED
,
1911 elfcpp::STV_DEFAULT
,
1913 true, // offset_is_from_end
1914 true); // only_if_ref
1919 // Define symbols for group signatures.
1922 Layout::define_group_signatures(Symbol_table
* symtab
)
1924 for (Group_signatures::iterator p
= this->group_signatures_
.begin();
1925 p
!= this->group_signatures_
.end();
1928 Symbol
* sym
= symtab
->lookup(p
->signature
, NULL
);
1930 p
->section
->set_info_symndx(sym
);
1933 // Force the name of the group section to the group
1934 // signature, and use the group's section symbol as the
1935 // signature symbol.
1936 if (strcmp(p
->section
->name(), p
->signature
) != 0)
1938 const char* name
= this->namepool_
.add(p
->signature
,
1940 p
->section
->set_name(name
);
1942 p
->section
->set_needs_symtab_index();
1943 p
->section
->set_info_section_symndx(p
->section
);
1947 this->group_signatures_
.clear();
1950 // Find the first read-only PT_LOAD segment, creating one if
1954 Layout::find_first_load_seg()
1956 Output_segment
* best
= NULL
;
1957 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
1958 p
!= this->segment_list_
.end();
1961 if ((*p
)->type() == elfcpp::PT_LOAD
1962 && ((*p
)->flags() & elfcpp::PF_R
) != 0
1963 && (parameters
->options().omagic()
1964 || ((*p
)->flags() & elfcpp::PF_W
) == 0))
1966 if (best
== NULL
|| this->segment_precedes(*p
, best
))
1973 gold_assert(!this->script_options_
->saw_phdrs_clause());
1975 Output_segment
* load_seg
= this->make_output_segment(elfcpp::PT_LOAD
,
1980 // Save states of all current output segments. Store saved states
1981 // in SEGMENT_STATES.
1984 Layout::save_segments(Segment_states
* segment_states
)
1986 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
1987 p
!= this->segment_list_
.end();
1990 Output_segment
* segment
= *p
;
1992 Output_segment
* copy
= new Output_segment(*segment
);
1993 (*segment_states
)[segment
] = copy
;
1997 // Restore states of output segments and delete any segment not found in
2001 Layout::restore_segments(const Segment_states
* segment_states
)
2003 // Go through the segment list and remove any segment added in the
2005 this->tls_segment_
= NULL
;
2006 this->relro_segment_
= NULL
;
2007 Segment_list::iterator list_iter
= this->segment_list_
.begin();
2008 while (list_iter
!= this->segment_list_
.end())
2010 Output_segment
* segment
= *list_iter
;
2011 Segment_states::const_iterator states_iter
=
2012 segment_states
->find(segment
);
2013 if (states_iter
!= segment_states
->end())
2015 const Output_segment
* copy
= states_iter
->second
;
2016 // Shallow copy to restore states.
2019 // Also fix up TLS and RELRO segment pointers as appropriate.
2020 if (segment
->type() == elfcpp::PT_TLS
)
2021 this->tls_segment_
= segment
;
2022 else if (segment
->type() == elfcpp::PT_GNU_RELRO
)
2023 this->relro_segment_
= segment
;
2029 list_iter
= this->segment_list_
.erase(list_iter
);
2030 // This is a segment created during section layout. It should be
2031 // safe to remove it since we should have removed all pointers to it.
2037 // Clean up after relaxation so that sections can be laid out again.
2040 Layout::clean_up_after_relaxation()
2042 // Restore the segments to point state just prior to the relaxation loop.
2043 Script_sections
* script_section
= this->script_options_
->script_sections();
2044 script_section
->release_segments();
2045 this->restore_segments(this->segment_states_
);
2047 // Reset section addresses and file offsets
2048 for (Section_list::iterator p
= this->section_list_
.begin();
2049 p
!= this->section_list_
.end();
2052 (*p
)->restore_states();
2054 // If an input section changes size because of relaxation,
2055 // we need to adjust the section offsets of all input sections.
2056 // after such a section.
2057 if ((*p
)->section_offsets_need_adjustment())
2058 (*p
)->adjust_section_offsets();
2060 (*p
)->reset_address_and_file_offset();
2063 // Reset special output object address and file offsets.
2064 for (Data_list::iterator p
= this->special_output_list_
.begin();
2065 p
!= this->special_output_list_
.end();
2067 (*p
)->reset_address_and_file_offset();
2069 // A linker script may have created some output section data objects.
2070 // They are useless now.
2071 for (Output_section_data_list::const_iterator p
=
2072 this->script_output_section_data_list_
.begin();
2073 p
!= this->script_output_section_data_list_
.end();
2076 this->script_output_section_data_list_
.clear();
2079 // Prepare for relaxation.
2082 Layout::prepare_for_relaxation()
2084 // Create an relaxation debug check if in debugging mode.
2085 if (is_debugging_enabled(DEBUG_RELAXATION
))
2086 this->relaxation_debug_check_
= new Relaxation_debug_check();
2088 // Save segment states.
2089 this->segment_states_
= new Segment_states();
2090 this->save_segments(this->segment_states_
);
2092 for(Section_list::const_iterator p
= this->section_list_
.begin();
2093 p
!= this->section_list_
.end();
2095 (*p
)->save_states();
2097 if (is_debugging_enabled(DEBUG_RELAXATION
))
2098 this->relaxation_debug_check_
->check_output_data_for_reset_values(
2099 this->section_list_
, this->special_output_list_
);
2101 // Also enable recording of output section data from scripts.
2102 this->record_output_section_data_from_script_
= true;
2105 // Relaxation loop body: If target has no relaxation, this runs only once
2106 // Otherwise, the target relaxation hook is called at the end of
2107 // each iteration. If the hook returns true, it means re-layout of
2108 // section is required.
2110 // The number of segments created by a linking script without a PHDRS
2111 // clause may be affected by section sizes and alignments. There is
2112 // a remote chance that relaxation causes different number of PT_LOAD
2113 // segments are created and sections are attached to different segments.
2114 // Therefore, we always throw away all segments created during section
2115 // layout. In order to be able to restart the section layout, we keep
2116 // a copy of the segment list right before the relaxation loop and use
2117 // that to restore the segments.
2119 // PASS is the current relaxation pass number.
2120 // SYMTAB is a symbol table.
2121 // PLOAD_SEG is the address of a pointer for the load segment.
2122 // PHDR_SEG is a pointer to the PHDR segment.
2123 // SEGMENT_HEADERS points to the output segment header.
2124 // FILE_HEADER points to the output file header.
2125 // PSHNDX is the address to store the output section index.
2128 Layout::relaxation_loop_body(
2131 Symbol_table
* symtab
,
2132 Output_segment
** pload_seg
,
2133 Output_segment
* phdr_seg
,
2134 Output_segment_headers
* segment_headers
,
2135 Output_file_header
* file_header
,
2136 unsigned int* pshndx
)
2138 // If this is not the first iteration, we need to clean up after
2139 // relaxation so that we can lay out the sections again.
2141 this->clean_up_after_relaxation();
2143 // If there is a SECTIONS clause, put all the input sections into
2144 // the required order.
2145 Output_segment
* load_seg
;
2146 if (this->script_options_
->saw_sections_clause())
2147 load_seg
= this->set_section_addresses_from_script(symtab
);
2148 else if (parameters
->options().relocatable())
2151 load_seg
= this->find_first_load_seg();
2153 if (parameters
->options().oformat_enum()
2154 != General_options::OBJECT_FORMAT_ELF
)
2157 // If the user set the address of the text segment, that may not be
2158 // compatible with putting the segment headers and file headers into
2160 if (parameters
->options().user_set_Ttext()
2161 && parameters
->options().Ttext() % target
->common_pagesize() != 0)
2167 gold_assert(phdr_seg
== NULL
2169 || this->script_options_
->saw_sections_clause());
2171 // If the address of the load segment we found has been set by
2172 // --section-start rather than by a script, then adjust the VMA and
2173 // LMA downward if possible to include the file and section headers.
2174 uint64_t header_gap
= 0;
2175 if (load_seg
!= NULL
2176 && load_seg
->are_addresses_set()
2177 && !this->script_options_
->saw_sections_clause()
2178 && !parameters
->options().relocatable())
2180 file_header
->finalize_data_size();
2181 segment_headers
->finalize_data_size();
2182 size_t sizeof_headers
= (file_header
->data_size()
2183 + segment_headers
->data_size());
2184 const uint64_t abi_pagesize
= target
->abi_pagesize();
2185 uint64_t hdr_paddr
= load_seg
->paddr() - sizeof_headers
;
2186 hdr_paddr
&= ~(abi_pagesize
- 1);
2187 uint64_t subtract
= load_seg
->paddr() - hdr_paddr
;
2188 if (load_seg
->paddr() < subtract
|| load_seg
->vaddr() < subtract
)
2192 load_seg
->set_addresses(load_seg
->vaddr() - subtract
,
2193 load_seg
->paddr() - subtract
);
2194 header_gap
= subtract
- sizeof_headers
;
2198 // Lay out the segment headers.
2199 if (!parameters
->options().relocatable())
2201 gold_assert(segment_headers
!= NULL
);
2202 if (header_gap
!= 0 && load_seg
!= NULL
)
2204 Output_data_zero_fill
* z
= new Output_data_zero_fill(header_gap
, 1);
2205 load_seg
->add_initial_output_data(z
);
2207 if (load_seg
!= NULL
)
2208 load_seg
->add_initial_output_data(segment_headers
);
2209 if (phdr_seg
!= NULL
)
2210 phdr_seg
->add_initial_output_data(segment_headers
);
2213 // Lay out the file header.
2214 if (load_seg
!= NULL
)
2215 load_seg
->add_initial_output_data(file_header
);
2217 if (this->script_options_
->saw_phdrs_clause()
2218 && !parameters
->options().relocatable())
2220 // Support use of FILEHDRS and PHDRS attachments in a PHDRS
2221 // clause in a linker script.
2222 Script_sections
* ss
= this->script_options_
->script_sections();
2223 ss
->put_headers_in_phdrs(file_header
, segment_headers
);
2226 // We set the output section indexes in set_segment_offsets and
2227 // set_section_indexes.
2230 // Set the file offsets of all the segments, and all the sections
2233 if (!parameters
->options().relocatable())
2234 off
= this->set_segment_offsets(target
, load_seg
, pshndx
);
2236 off
= this->set_relocatable_section_offsets(file_header
, pshndx
);
2238 // Verify that the dummy relaxation does not change anything.
2239 if (is_debugging_enabled(DEBUG_RELAXATION
))
2242 this->relaxation_debug_check_
->read_sections(this->section_list_
);
2244 this->relaxation_debug_check_
->verify_sections(this->section_list_
);
2247 *pload_seg
= load_seg
;
2251 // Search the list of patterns and find the postion of the given section
2252 // name in the output section. If the section name matches a glob
2253 // pattern and a non-glob name, then the non-glob position takes
2254 // precedence. Return 0 if no match is found.
2257 Layout::find_section_order_index(const std::string
& section_name
)
2259 Unordered_map
<std::string
, unsigned int>::iterator map_it
;
2260 map_it
= this->input_section_position_
.find(section_name
);
2261 if (map_it
!= this->input_section_position_
.end())
2262 return map_it
->second
;
2264 // Absolute match failed. Linear search the glob patterns.
2265 std::vector
<std::string
>::iterator it
;
2266 for (it
= this->input_section_glob_
.begin();
2267 it
!= this->input_section_glob_
.end();
2270 if (fnmatch((*it
).c_str(), section_name
.c_str(), FNM_NOESCAPE
) == 0)
2272 map_it
= this->input_section_position_
.find(*it
);
2273 gold_assert(map_it
!= this->input_section_position_
.end());
2274 return map_it
->second
;
2280 // Read the sequence of input sections from the file specified with
2281 // option --section-ordering-file.
2284 Layout::read_layout_from_file()
2286 const char* filename
= parameters
->options().section_ordering_file();
2292 gold_fatal(_("unable to open --section-ordering-file file %s: %s"),
2293 filename
, strerror(errno
));
2295 std::getline(in
, line
); // this chops off the trailing \n, if any
2296 unsigned int position
= 1;
2297 this->set_section_ordering_specified();
2301 if (!line
.empty() && line
[line
.length() - 1] == '\r') // Windows
2302 line
.resize(line
.length() - 1);
2303 // Ignore comments, beginning with '#'
2306 std::getline(in
, line
);
2309 this->input_section_position_
[line
] = position
;
2310 // Store all glob patterns in a vector.
2311 if (is_wildcard_string(line
.c_str()))
2312 this->input_section_glob_
.push_back(line
);
2314 std::getline(in
, line
);
2318 // Finalize the layout. When this is called, we have created all the
2319 // output sections and all the output segments which are based on
2320 // input sections. We have several things to do, and we have to do
2321 // them in the right order, so that we get the right results correctly
2324 // 1) Finalize the list of output segments and create the segment
2327 // 2) Finalize the dynamic symbol table and associated sections.
2329 // 3) Determine the final file offset of all the output segments.
2331 // 4) Determine the final file offset of all the SHF_ALLOC output
2334 // 5) Create the symbol table sections and the section name table
2337 // 6) Finalize the symbol table: set symbol values to their final
2338 // value and make a final determination of which symbols are going
2339 // into the output symbol table.
2341 // 7) Create the section table header.
2343 // 8) Determine the final file offset of all the output sections which
2344 // are not SHF_ALLOC, including the section table header.
2346 // 9) Finalize the ELF file header.
2348 // This function returns the size of the output file.
2351 Layout::finalize(const Input_objects
* input_objects
, Symbol_table
* symtab
,
2352 Target
* target
, const Task
* task
)
2354 target
->finalize_sections(this, input_objects
, symtab
);
2356 this->count_local_symbols(task
, input_objects
);
2358 this->link_stabs_sections();
2360 Output_segment
* phdr_seg
= NULL
;
2361 if (!parameters
->options().relocatable() && !parameters
->doing_static_link())
2363 // There was a dynamic object in the link. We need to create
2364 // some information for the dynamic linker.
2366 // Create the PT_PHDR segment which will hold the program
2368 if (!this->script_options_
->saw_phdrs_clause())
2369 phdr_seg
= this->make_output_segment(elfcpp::PT_PHDR
, elfcpp::PF_R
);
2371 // Create the dynamic symbol table, including the hash table.
2372 Output_section
* dynstr
;
2373 std::vector
<Symbol
*> dynamic_symbols
;
2374 unsigned int local_dynamic_count
;
2375 Versions
versions(*this->script_options()->version_script_info(),
2377 this->create_dynamic_symtab(input_objects
, symtab
, &dynstr
,
2378 &local_dynamic_count
, &dynamic_symbols
,
2381 // Create the .interp section to hold the name of the
2382 // interpreter, and put it in a PT_INTERP segment. Don't do it
2383 // if we saw a .interp section in an input file.
2384 if ((!parameters
->options().shared()
2385 || parameters
->options().dynamic_linker() != NULL
)
2386 && this->interp_segment_
== NULL
)
2387 this->create_interp(target
);
2389 // Finish the .dynamic section to hold the dynamic data, and put
2390 // it in a PT_DYNAMIC segment.
2391 this->finish_dynamic_section(input_objects
, symtab
);
2393 // We should have added everything we need to the dynamic string
2395 this->dynpool_
.set_string_offsets();
2397 // Create the version sections. We can't do this until the
2398 // dynamic string table is complete.
2399 this->create_version_sections(&versions
, symtab
, local_dynamic_count
,
2400 dynamic_symbols
, dynstr
);
2402 // Set the size of the _DYNAMIC symbol. We can't do this until
2403 // after we call create_version_sections.
2404 this->set_dynamic_symbol_size(symtab
);
2407 // Create segment headers.
2408 Output_segment_headers
* segment_headers
=
2409 (parameters
->options().relocatable()
2411 : new Output_segment_headers(this->segment_list_
));
2413 // Lay out the file header.
2414 Output_file_header
* file_header
= new Output_file_header(target
, symtab
,
2417 this->special_output_list_
.push_back(file_header
);
2418 if (segment_headers
!= NULL
)
2419 this->special_output_list_
.push_back(segment_headers
);
2421 // Find approriate places for orphan output sections if we are using
2423 if (this->script_options_
->saw_sections_clause())
2424 this->place_orphan_sections_in_script();
2426 Output_segment
* load_seg
;
2431 // Take a snapshot of the section layout as needed.
2432 if (target
->may_relax())
2433 this->prepare_for_relaxation();
2435 // Run the relaxation loop to lay out sections.
2438 off
= this->relaxation_loop_body(pass
, target
, symtab
, &load_seg
,
2439 phdr_seg
, segment_headers
, file_header
,
2443 while (target
->may_relax()
2444 && target
->relax(pass
, input_objects
, symtab
, this, task
));
2446 // Set the file offsets of all the non-data sections we've seen so
2447 // far which don't have to wait for the input sections. We need
2448 // this in order to finalize local symbols in non-allocated
2450 off
= this->set_section_offsets(off
, BEFORE_INPUT_SECTIONS_PASS
);
2452 // Set the section indexes of all unallocated sections seen so far,
2453 // in case any of them are somehow referenced by a symbol.
2454 shndx
= this->set_section_indexes(shndx
);
2456 // Create the symbol table sections.
2457 this->create_symtab_sections(input_objects
, symtab
, shndx
, &off
);
2458 if (!parameters
->doing_static_link())
2459 this->assign_local_dynsym_offsets(input_objects
);
2461 // Process any symbol assignments from a linker script. This must
2462 // be called after the symbol table has been finalized.
2463 this->script_options_
->finalize_symbols(symtab
, this);
2465 // Create the incremental inputs sections.
2466 if (this->incremental_inputs_
)
2468 this->incremental_inputs_
->finalize();
2469 this->create_incremental_info_sections(symtab
);
2472 // Create the .shstrtab section.
2473 Output_section
* shstrtab_section
= this->create_shstrtab();
2475 // Set the file offsets of the rest of the non-data sections which
2476 // don't have to wait for the input sections.
2477 off
= this->set_section_offsets(off
, BEFORE_INPUT_SECTIONS_PASS
);
2479 // Now that all sections have been created, set the section indexes
2480 // for any sections which haven't been done yet.
2481 shndx
= this->set_section_indexes(shndx
);
2483 // Create the section table header.
2484 this->create_shdrs(shstrtab_section
, &off
);
2486 // If there are no sections which require postprocessing, we can
2487 // handle the section names now, and avoid a resize later.
2488 if (!this->any_postprocessing_sections_
)
2490 off
= this->set_section_offsets(off
,
2491 POSTPROCESSING_SECTIONS_PASS
);
2493 this->set_section_offsets(off
,
2494 STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
);
2497 file_header
->set_section_info(this->section_headers_
, shstrtab_section
);
2499 // Now we know exactly where everything goes in the output file
2500 // (except for non-allocated sections which require postprocessing).
2501 Output_data::layout_complete();
2503 this->output_file_size_
= off
;
2508 // Create a note header following the format defined in the ELF ABI.
2509 // NAME is the name, NOTE_TYPE is the type, SECTION_NAME is the name
2510 // of the section to create, DESCSZ is the size of the descriptor.
2511 // ALLOCATE is true if the section should be allocated in memory.
2512 // This returns the new note section. It sets *TRAILING_PADDING to
2513 // the number of trailing zero bytes required.
2516 Layout::create_note(const char* name
, int note_type
,
2517 const char* section_name
, size_t descsz
,
2518 bool allocate
, size_t* trailing_padding
)
2520 // Authorities all agree that the values in a .note field should
2521 // be aligned on 4-byte boundaries for 32-bit binaries. However,
2522 // they differ on what the alignment is for 64-bit binaries.
2523 // The GABI says unambiguously they take 8-byte alignment:
2524 // http://sco.com/developers/gabi/latest/ch5.pheader.html#note_section
2525 // Other documentation says alignment should always be 4 bytes:
2526 // http://www.netbsd.org/docs/kernel/elf-notes.html#note-format
2527 // GNU ld and GNU readelf both support the latter (at least as of
2528 // version 2.16.91), and glibc always generates the latter for
2529 // .note.ABI-tag (as of version 1.6), so that's the one we go with
2531 #ifdef GABI_FORMAT_FOR_DOTNOTE_SECTION // This is not defined by default.
2532 const int size
= parameters
->target().get_size();
2534 const int size
= 32;
2537 // The contents of the .note section.
2538 size_t namesz
= strlen(name
) + 1;
2539 size_t aligned_namesz
= align_address(namesz
, size
/ 8);
2540 size_t aligned_descsz
= align_address(descsz
, size
/ 8);
2542 size_t notehdrsz
= 3 * (size
/ 8) + aligned_namesz
;
2544 unsigned char* buffer
= new unsigned char[notehdrsz
];
2545 memset(buffer
, 0, notehdrsz
);
2547 bool is_big_endian
= parameters
->target().is_big_endian();
2553 elfcpp::Swap
<32, false>::writeval(buffer
, namesz
);
2554 elfcpp::Swap
<32, false>::writeval(buffer
+ 4, descsz
);
2555 elfcpp::Swap
<32, false>::writeval(buffer
+ 8, note_type
);
2559 elfcpp::Swap
<32, true>::writeval(buffer
, namesz
);
2560 elfcpp::Swap
<32, true>::writeval(buffer
+ 4, descsz
);
2561 elfcpp::Swap
<32, true>::writeval(buffer
+ 8, note_type
);
2564 else if (size
== 64)
2568 elfcpp::Swap
<64, false>::writeval(buffer
, namesz
);
2569 elfcpp::Swap
<64, false>::writeval(buffer
+ 8, descsz
);
2570 elfcpp::Swap
<64, false>::writeval(buffer
+ 16, note_type
);
2574 elfcpp::Swap
<64, true>::writeval(buffer
, namesz
);
2575 elfcpp::Swap
<64, true>::writeval(buffer
+ 8, descsz
);
2576 elfcpp::Swap
<64, true>::writeval(buffer
+ 16, note_type
);
2582 memcpy(buffer
+ 3 * (size
/ 8), name
, namesz
);
2584 elfcpp::Elf_Xword flags
= 0;
2585 Output_section_order order
= ORDER_INVALID
;
2588 flags
= elfcpp::SHF_ALLOC
;
2589 order
= ORDER_RO_NOTE
;
2591 Output_section
* os
= this->choose_output_section(NULL
, section_name
,
2593 flags
, false, order
, false);
2597 Output_section_data
* posd
= new Output_data_const_buffer(buffer
, notehdrsz
,
2600 os
->add_output_section_data(posd
);
2602 *trailing_padding
= aligned_descsz
- descsz
;
2607 // For an executable or shared library, create a note to record the
2608 // version of gold used to create the binary.
2611 Layout::create_gold_note()
2613 if (parameters
->options().relocatable()
2614 || parameters
->incremental_update())
2617 std::string desc
= std::string("gold ") + gold::get_version_string();
2619 size_t trailing_padding
;
2620 Output_section
* os
= this->create_note("GNU", elfcpp::NT_GNU_GOLD_VERSION
,
2621 ".note.gnu.gold-version", desc
.size(),
2622 false, &trailing_padding
);
2626 Output_section_data
* posd
= new Output_data_const(desc
, 4);
2627 os
->add_output_section_data(posd
);
2629 if (trailing_padding
> 0)
2631 posd
= new Output_data_zero_fill(trailing_padding
, 0);
2632 os
->add_output_section_data(posd
);
2636 // Record whether the stack should be executable. This can be set
2637 // from the command line using the -z execstack or -z noexecstack
2638 // options. Otherwise, if any input file has a .note.GNU-stack
2639 // section with the SHF_EXECINSTR flag set, the stack should be
2640 // executable. Otherwise, if at least one input file a
2641 // .note.GNU-stack section, and some input file has no .note.GNU-stack
2642 // section, we use the target default for whether the stack should be
2643 // executable. Otherwise, we don't generate a stack note. When
2644 // generating a object file, we create a .note.GNU-stack section with
2645 // the appropriate marking. When generating an executable or shared
2646 // library, we create a PT_GNU_STACK segment.
2649 Layout::create_executable_stack_info()
2651 bool is_stack_executable
;
2652 if (parameters
->options().is_execstack_set())
2653 is_stack_executable
= parameters
->options().is_stack_executable();
2654 else if (!this->input_with_gnu_stack_note_
)
2658 if (this->input_requires_executable_stack_
)
2659 is_stack_executable
= true;
2660 else if (this->input_without_gnu_stack_note_
)
2661 is_stack_executable
=
2662 parameters
->target().is_default_stack_executable();
2664 is_stack_executable
= false;
2667 if (parameters
->options().relocatable())
2669 const char* name
= this->namepool_
.add(".note.GNU-stack", false, NULL
);
2670 elfcpp::Elf_Xword flags
= 0;
2671 if (is_stack_executable
)
2672 flags
|= elfcpp::SHF_EXECINSTR
;
2673 this->make_output_section(name
, elfcpp::SHT_PROGBITS
, flags
,
2674 ORDER_INVALID
, false);
2678 if (this->script_options_
->saw_phdrs_clause())
2680 int flags
= elfcpp::PF_R
| elfcpp::PF_W
;
2681 if (is_stack_executable
)
2682 flags
|= elfcpp::PF_X
;
2683 this->make_output_segment(elfcpp::PT_GNU_STACK
, flags
);
2687 // If --build-id was used, set up the build ID note.
2690 Layout::create_build_id()
2692 if (!parameters
->options().user_set_build_id())
2695 const char* style
= parameters
->options().build_id();
2696 if (strcmp(style
, "none") == 0)
2699 // Set DESCSZ to the size of the note descriptor. When possible,
2700 // set DESC to the note descriptor contents.
2703 if (strcmp(style
, "md5") == 0)
2705 else if (strcmp(style
, "sha1") == 0)
2707 else if (strcmp(style
, "uuid") == 0)
2709 const size_t uuidsz
= 128 / 8;
2711 char buffer
[uuidsz
];
2712 memset(buffer
, 0, uuidsz
);
2714 int descriptor
= open_descriptor(-1, "/dev/urandom", O_RDONLY
);
2716 gold_error(_("--build-id=uuid failed: could not open /dev/urandom: %s"),
2720 ssize_t got
= ::read(descriptor
, buffer
, uuidsz
);
2721 release_descriptor(descriptor
, true);
2723 gold_error(_("/dev/urandom: read failed: %s"), strerror(errno
));
2724 else if (static_cast<size_t>(got
) != uuidsz
)
2725 gold_error(_("/dev/urandom: expected %zu bytes, got %zd bytes"),
2729 desc
.assign(buffer
, uuidsz
);
2732 else if (strncmp(style
, "0x", 2) == 0)
2735 const char* p
= style
+ 2;
2738 if (hex_p(p
[0]) && hex_p(p
[1]))
2740 char c
= (hex_value(p
[0]) << 4) | hex_value(p
[1]);
2744 else if (*p
== '-' || *p
== ':')
2747 gold_fatal(_("--build-id argument '%s' not a valid hex number"),
2750 descsz
= desc
.size();
2753 gold_fatal(_("unrecognized --build-id argument '%s'"), style
);
2756 size_t trailing_padding
;
2757 Output_section
* os
= this->create_note("GNU", elfcpp::NT_GNU_BUILD_ID
,
2758 ".note.gnu.build-id", descsz
, true,
2765 // We know the value already, so we fill it in now.
2766 gold_assert(desc
.size() == descsz
);
2768 Output_section_data
* posd
= new Output_data_const(desc
, 4);
2769 os
->add_output_section_data(posd
);
2771 if (trailing_padding
!= 0)
2773 posd
= new Output_data_zero_fill(trailing_padding
, 0);
2774 os
->add_output_section_data(posd
);
2779 // We need to compute a checksum after we have completed the
2781 gold_assert(trailing_padding
== 0);
2782 this->build_id_note_
= new Output_data_zero_fill(descsz
, 4);
2783 os
->add_output_section_data(this->build_id_note_
);
2787 // If we have both .stabXX and .stabXXstr sections, then the sh_link
2788 // field of the former should point to the latter. I'm not sure who
2789 // started this, but the GNU linker does it, and some tools depend
2793 Layout::link_stabs_sections()
2795 if (!this->have_stabstr_section_
)
2798 for (Section_list::iterator p
= this->section_list_
.begin();
2799 p
!= this->section_list_
.end();
2802 if ((*p
)->type() != elfcpp::SHT_STRTAB
)
2805 const char* name
= (*p
)->name();
2806 if (strncmp(name
, ".stab", 5) != 0)
2809 size_t len
= strlen(name
);
2810 if (strcmp(name
+ len
- 3, "str") != 0)
2813 std::string
stab_name(name
, len
- 3);
2814 Output_section
* stab_sec
;
2815 stab_sec
= this->find_output_section(stab_name
.c_str());
2816 if (stab_sec
!= NULL
)
2817 stab_sec
->set_link_section(*p
);
2821 // Create .gnu_incremental_inputs and related sections needed
2822 // for the next run of incremental linking to check what has changed.
2825 Layout::create_incremental_info_sections(Symbol_table
* symtab
)
2827 Incremental_inputs
* incr
= this->incremental_inputs_
;
2829 gold_assert(incr
!= NULL
);
2831 // Create the .gnu_incremental_inputs, _symtab, and _relocs input sections.
2832 incr
->create_data_sections(symtab
);
2834 // Add the .gnu_incremental_inputs section.
2835 const char* incremental_inputs_name
=
2836 this->namepool_
.add(".gnu_incremental_inputs", false, NULL
);
2837 Output_section
* incremental_inputs_os
=
2838 this->make_output_section(incremental_inputs_name
,
2839 elfcpp::SHT_GNU_INCREMENTAL_INPUTS
, 0,
2840 ORDER_INVALID
, false);
2841 incremental_inputs_os
->add_output_section_data(incr
->inputs_section());
2843 // Add the .gnu_incremental_symtab section.
2844 const char* incremental_symtab_name
=
2845 this->namepool_
.add(".gnu_incremental_symtab", false, NULL
);
2846 Output_section
* incremental_symtab_os
=
2847 this->make_output_section(incremental_symtab_name
,
2848 elfcpp::SHT_GNU_INCREMENTAL_SYMTAB
, 0,
2849 ORDER_INVALID
, false);
2850 incremental_symtab_os
->add_output_section_data(incr
->symtab_section());
2851 incremental_symtab_os
->set_entsize(4);
2853 // Add the .gnu_incremental_relocs section.
2854 const char* incremental_relocs_name
=
2855 this->namepool_
.add(".gnu_incremental_relocs", false, NULL
);
2856 Output_section
* incremental_relocs_os
=
2857 this->make_output_section(incremental_relocs_name
,
2858 elfcpp::SHT_GNU_INCREMENTAL_RELOCS
, 0,
2859 ORDER_INVALID
, false);
2860 incremental_relocs_os
->add_output_section_data(incr
->relocs_section());
2861 incremental_relocs_os
->set_entsize(incr
->relocs_entsize());
2863 // Add the .gnu_incremental_got_plt section.
2864 const char* incremental_got_plt_name
=
2865 this->namepool_
.add(".gnu_incremental_got_plt", false, NULL
);
2866 Output_section
* incremental_got_plt_os
=
2867 this->make_output_section(incremental_got_plt_name
,
2868 elfcpp::SHT_GNU_INCREMENTAL_GOT_PLT
, 0,
2869 ORDER_INVALID
, false);
2870 incremental_got_plt_os
->add_output_section_data(incr
->got_plt_section());
2872 // Add the .gnu_incremental_strtab section.
2873 const char* incremental_strtab_name
=
2874 this->namepool_
.add(".gnu_incremental_strtab", false, NULL
);
2875 Output_section
* incremental_strtab_os
= this->make_output_section(incremental_strtab_name
,
2876 elfcpp::SHT_STRTAB
, 0,
2877 ORDER_INVALID
, false);
2878 Output_data_strtab
* strtab_data
=
2879 new Output_data_strtab(incr
->get_stringpool());
2880 incremental_strtab_os
->add_output_section_data(strtab_data
);
2882 incremental_inputs_os
->set_after_input_sections();
2883 incremental_symtab_os
->set_after_input_sections();
2884 incremental_relocs_os
->set_after_input_sections();
2885 incremental_got_plt_os
->set_after_input_sections();
2887 incremental_inputs_os
->set_link_section(incremental_strtab_os
);
2888 incremental_symtab_os
->set_link_section(incremental_inputs_os
);
2889 incremental_relocs_os
->set_link_section(incremental_inputs_os
);
2890 incremental_got_plt_os
->set_link_section(incremental_inputs_os
);
2893 // Return whether SEG1 should be before SEG2 in the output file. This
2894 // is based entirely on the segment type and flags. When this is
2895 // called the segment addresses have normally not yet been set.
2898 Layout::segment_precedes(const Output_segment
* seg1
,
2899 const Output_segment
* seg2
)
2901 elfcpp::Elf_Word type1
= seg1
->type();
2902 elfcpp::Elf_Word type2
= seg2
->type();
2904 // The single PT_PHDR segment is required to precede any loadable
2905 // segment. We simply make it always first.
2906 if (type1
== elfcpp::PT_PHDR
)
2908 gold_assert(type2
!= elfcpp::PT_PHDR
);
2911 if (type2
== elfcpp::PT_PHDR
)
2914 // The single PT_INTERP segment is required to precede any loadable
2915 // segment. We simply make it always second.
2916 if (type1
== elfcpp::PT_INTERP
)
2918 gold_assert(type2
!= elfcpp::PT_INTERP
);
2921 if (type2
== elfcpp::PT_INTERP
)
2924 // We then put PT_LOAD segments before any other segments.
2925 if (type1
== elfcpp::PT_LOAD
&& type2
!= elfcpp::PT_LOAD
)
2927 if (type2
== elfcpp::PT_LOAD
&& type1
!= elfcpp::PT_LOAD
)
2930 // We put the PT_TLS segment last except for the PT_GNU_RELRO
2931 // segment, because that is where the dynamic linker expects to find
2932 // it (this is just for efficiency; other positions would also work
2934 if (type1
== elfcpp::PT_TLS
2935 && type2
!= elfcpp::PT_TLS
2936 && type2
!= elfcpp::PT_GNU_RELRO
)
2938 if (type2
== elfcpp::PT_TLS
2939 && type1
!= elfcpp::PT_TLS
2940 && type1
!= elfcpp::PT_GNU_RELRO
)
2943 // We put the PT_GNU_RELRO segment last, because that is where the
2944 // dynamic linker expects to find it (as with PT_TLS, this is just
2946 if (type1
== elfcpp::PT_GNU_RELRO
&& type2
!= elfcpp::PT_GNU_RELRO
)
2948 if (type2
== elfcpp::PT_GNU_RELRO
&& type1
!= elfcpp::PT_GNU_RELRO
)
2951 const elfcpp::Elf_Word flags1
= seg1
->flags();
2952 const elfcpp::Elf_Word flags2
= seg2
->flags();
2954 // The order of non-PT_LOAD segments is unimportant. We simply sort
2955 // by the numeric segment type and flags values. There should not
2956 // be more than one segment with the same type and flags.
2957 if (type1
!= elfcpp::PT_LOAD
)
2960 return type1
< type2
;
2961 gold_assert(flags1
!= flags2
);
2962 return flags1
< flags2
;
2965 // If the addresses are set already, sort by load address.
2966 if (seg1
->are_addresses_set())
2968 if (!seg2
->are_addresses_set())
2971 unsigned int section_count1
= seg1
->output_section_count();
2972 unsigned int section_count2
= seg2
->output_section_count();
2973 if (section_count1
== 0 && section_count2
> 0)
2975 if (section_count1
> 0 && section_count2
== 0)
2978 uint64_t paddr1
= (seg1
->are_addresses_set()
2980 : seg1
->first_section_load_address());
2981 uint64_t paddr2
= (seg2
->are_addresses_set()
2983 : seg2
->first_section_load_address());
2985 if (paddr1
!= paddr2
)
2986 return paddr1
< paddr2
;
2988 else if (seg2
->are_addresses_set())
2991 // A segment which holds large data comes after a segment which does
2992 // not hold large data.
2993 if (seg1
->is_large_data_segment())
2995 if (!seg2
->is_large_data_segment())
2998 else if (seg2
->is_large_data_segment())
3001 // Otherwise, we sort PT_LOAD segments based on the flags. Readonly
3002 // segments come before writable segments. Then writable segments
3003 // with data come before writable segments without data. Then
3004 // executable segments come before non-executable segments. Then
3005 // the unlikely case of a non-readable segment comes before the
3006 // normal case of a readable segment. If there are multiple
3007 // segments with the same type and flags, we require that the
3008 // address be set, and we sort by virtual address and then physical
3010 if ((flags1
& elfcpp::PF_W
) != (flags2
& elfcpp::PF_W
))
3011 return (flags1
& elfcpp::PF_W
) == 0;
3012 if ((flags1
& elfcpp::PF_W
) != 0
3013 && seg1
->has_any_data_sections() != seg2
->has_any_data_sections())
3014 return seg1
->has_any_data_sections();
3015 if ((flags1
& elfcpp::PF_X
) != (flags2
& elfcpp::PF_X
))
3016 return (flags1
& elfcpp::PF_X
) != 0;
3017 if ((flags1
& elfcpp::PF_R
) != (flags2
& elfcpp::PF_R
))
3018 return (flags1
& elfcpp::PF_R
) == 0;
3020 // We shouldn't get here--we shouldn't create segments which we
3021 // can't distinguish. Unless of course we are using a weird linker
3022 // script or overlapping --section-start options.
3023 gold_assert(this->script_options_
->saw_phdrs_clause()
3024 || parameters
->options().any_section_start());
3028 // Increase OFF so that it is congruent to ADDR modulo ABI_PAGESIZE.
3031 align_file_offset(off_t off
, uint64_t addr
, uint64_t abi_pagesize
)
3033 uint64_t unsigned_off
= off
;
3034 uint64_t aligned_off
= ((unsigned_off
& ~(abi_pagesize
- 1))
3035 | (addr
& (abi_pagesize
- 1)));
3036 if (aligned_off
< unsigned_off
)
3037 aligned_off
+= abi_pagesize
;
3041 // Set the file offsets of all the segments, and all the sections they
3042 // contain. They have all been created. LOAD_SEG must be be laid out
3043 // first. Return the offset of the data to follow.
3046 Layout::set_segment_offsets(const Target
* target
, Output_segment
* load_seg
,
3047 unsigned int* pshndx
)
3049 // Sort them into the final order. We use a stable sort so that we
3050 // don't randomize the order of indistinguishable segments created
3051 // by linker scripts.
3052 std::stable_sort(this->segment_list_
.begin(), this->segment_list_
.end(),
3053 Layout::Compare_segments(this));
3055 // Find the PT_LOAD segments, and set their addresses and offsets
3056 // and their section's addresses and offsets.
3058 if (parameters
->options().user_set_Ttext())
3059 addr
= parameters
->options().Ttext();
3060 else if (parameters
->options().output_is_position_independent())
3063 addr
= target
->default_text_segment_address();
3066 // If LOAD_SEG is NULL, then the file header and segment headers
3067 // will not be loadable. But they still need to be at offset 0 in
3068 // the file. Set their offsets now.
3069 if (load_seg
== NULL
)
3071 for (Data_list::iterator p
= this->special_output_list_
.begin();
3072 p
!= this->special_output_list_
.end();
3075 off
= align_address(off
, (*p
)->addralign());
3076 (*p
)->set_address_and_file_offset(0, off
);
3077 off
+= (*p
)->data_size();
3081 unsigned int increase_relro
= this->increase_relro_
;
3082 if (this->script_options_
->saw_sections_clause())
3085 const bool check_sections
= parameters
->options().check_sections();
3086 Output_segment
* last_load_segment
= NULL
;
3088 for (Segment_list::iterator p
= this->segment_list_
.begin();
3089 p
!= this->segment_list_
.end();
3092 if ((*p
)->type() == elfcpp::PT_LOAD
)
3094 if (load_seg
!= NULL
&& load_seg
!= *p
)
3098 bool are_addresses_set
= (*p
)->are_addresses_set();
3099 if (are_addresses_set
)
3101 // When it comes to setting file offsets, we care about
3102 // the physical address.
3103 addr
= (*p
)->paddr();
3105 else if (parameters
->options().user_set_Ttext()
3106 && ((*p
)->flags() & elfcpp::PF_W
) == 0)
3108 are_addresses_set
= true;
3110 else if (parameters
->options().user_set_Tdata()
3111 && ((*p
)->flags() & elfcpp::PF_W
) != 0
3112 && (!parameters
->options().user_set_Tbss()
3113 || (*p
)->has_any_data_sections()))
3115 addr
= parameters
->options().Tdata();
3116 are_addresses_set
= true;
3118 else if (parameters
->options().user_set_Tbss()
3119 && ((*p
)->flags() & elfcpp::PF_W
) != 0
3120 && !(*p
)->has_any_data_sections())
3122 addr
= parameters
->options().Tbss();
3123 are_addresses_set
= true;
3126 uint64_t orig_addr
= addr
;
3127 uint64_t orig_off
= off
;
3129 uint64_t aligned_addr
= 0;
3130 uint64_t abi_pagesize
= target
->abi_pagesize();
3131 uint64_t common_pagesize
= target
->common_pagesize();
3133 if (!parameters
->options().nmagic()
3134 && !parameters
->options().omagic())
3135 (*p
)->set_minimum_p_align(common_pagesize
);
3137 if (!are_addresses_set
)
3139 // Skip the address forward one page, maintaining the same
3140 // position within the page. This lets us store both segments
3141 // overlapping on a single page in the file, but the loader will
3142 // put them on different pages in memory. We will revisit this
3143 // decision once we know the size of the segment.
3145 addr
= align_address(addr
, (*p
)->maximum_alignment());
3146 aligned_addr
= addr
;
3148 if ((addr
& (abi_pagesize
- 1)) != 0)
3149 addr
= addr
+ abi_pagesize
;
3151 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
3154 if (!parameters
->options().nmagic()
3155 && !parameters
->options().omagic())
3156 off
= align_file_offset(off
, addr
, abi_pagesize
);
3157 else if (load_seg
== NULL
)
3159 // This is -N or -n with a section script which prevents
3160 // us from using a load segment. We need to ensure that
3161 // the file offset is aligned to the alignment of the
3162 // segment. This is because the linker script
3163 // implicitly assumed a zero offset. If we don't align
3164 // here, then the alignment of the sections in the
3165 // linker script may not match the alignment of the
3166 // sections in the set_section_addresses call below,
3167 // causing an error about dot moving backward.
3168 off
= align_address(off
, (*p
)->maximum_alignment());
3171 unsigned int shndx_hold
= *pshndx
;
3172 bool has_relro
= false;
3173 uint64_t new_addr
= (*p
)->set_section_addresses(this, false, addr
,
3178 // Now that we know the size of this segment, we may be able
3179 // to save a page in memory, at the cost of wasting some
3180 // file space, by instead aligning to the start of a new
3181 // page. Here we use the real machine page size rather than
3182 // the ABI mandated page size. If the segment has been
3183 // aligned so that the relro data ends at a page boundary,
3184 // we do not try to realign it.
3186 if (!are_addresses_set
3188 && aligned_addr
!= addr
3189 && !parameters
->incremental())
3191 uint64_t first_off
= (common_pagesize
3193 & (common_pagesize
- 1)));
3194 uint64_t last_off
= new_addr
& (common_pagesize
- 1);
3197 && ((aligned_addr
& ~ (common_pagesize
- 1))
3198 != (new_addr
& ~ (common_pagesize
- 1)))
3199 && first_off
+ last_off
<= common_pagesize
)
3201 *pshndx
= shndx_hold
;
3202 addr
= align_address(aligned_addr
, common_pagesize
);
3203 addr
= align_address(addr
, (*p
)->maximum_alignment());
3204 off
= orig_off
+ ((addr
- orig_addr
) & (abi_pagesize
- 1));
3205 off
= align_file_offset(off
, addr
, abi_pagesize
);
3207 increase_relro
= this->increase_relro_
;
3208 if (this->script_options_
->saw_sections_clause())
3212 new_addr
= (*p
)->set_section_addresses(this, true, addr
,
3221 // Implement --check-sections. We know that the segments
3222 // are sorted by LMA.
3223 if (check_sections
&& last_load_segment
!= NULL
)
3225 gold_assert(last_load_segment
->paddr() <= (*p
)->paddr());
3226 if (last_load_segment
->paddr() + last_load_segment
->memsz()
3229 unsigned long long lb1
= last_load_segment
->paddr();
3230 unsigned long long le1
= lb1
+ last_load_segment
->memsz();
3231 unsigned long long lb2
= (*p
)->paddr();
3232 unsigned long long le2
= lb2
+ (*p
)->memsz();
3233 gold_error(_("load segment overlap [0x%llx -> 0x%llx] and "
3234 "[0x%llx -> 0x%llx]"),
3235 lb1
, le1
, lb2
, le2
);
3238 last_load_segment
= *p
;
3242 // Handle the non-PT_LOAD segments, setting their offsets from their
3243 // section's offsets.
3244 for (Segment_list::iterator p
= this->segment_list_
.begin();
3245 p
!= this->segment_list_
.end();
3248 if ((*p
)->type() != elfcpp::PT_LOAD
)
3249 (*p
)->set_offset((*p
)->type() == elfcpp::PT_GNU_RELRO
3254 // Set the TLS offsets for each section in the PT_TLS segment.
3255 if (this->tls_segment_
!= NULL
)
3256 this->tls_segment_
->set_tls_offsets();
3261 // Set the offsets of all the allocated sections when doing a
3262 // relocatable link. This does the same jobs as set_segment_offsets,
3263 // only for a relocatable link.
3266 Layout::set_relocatable_section_offsets(Output_data
* file_header
,
3267 unsigned int* pshndx
)
3271 file_header
->set_address_and_file_offset(0, 0);
3272 off
+= file_header
->data_size();
3274 for (Section_list::iterator p
= this->section_list_
.begin();
3275 p
!= this->section_list_
.end();
3278 // We skip unallocated sections here, except that group sections
3279 // have to come first.
3280 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) == 0
3281 && (*p
)->type() != elfcpp::SHT_GROUP
)
3284 off
= align_address(off
, (*p
)->addralign());
3286 // The linker script might have set the address.
3287 if (!(*p
)->is_address_valid())
3288 (*p
)->set_address(0);
3289 (*p
)->set_file_offset(off
);
3290 (*p
)->finalize_data_size();
3291 off
+= (*p
)->data_size();
3293 (*p
)->set_out_shndx(*pshndx
);
3300 // Set the file offset of all the sections not associated with a
3304 Layout::set_section_offsets(off_t off
, Layout::Section_offset_pass pass
)
3306 off_t startoff
= off
;
3309 for (Section_list::iterator p
= this->unattached_section_list_
.begin();
3310 p
!= this->unattached_section_list_
.end();
3313 // The symtab section is handled in create_symtab_sections.
3314 if (*p
== this->symtab_section_
)
3317 // If we've already set the data size, don't set it again.
3318 if ((*p
)->is_offset_valid() && (*p
)->is_data_size_valid())
3321 if (pass
== BEFORE_INPUT_SECTIONS_PASS
3322 && (*p
)->requires_postprocessing())
3324 (*p
)->create_postprocessing_buffer();
3325 this->any_postprocessing_sections_
= true;
3328 if (pass
== BEFORE_INPUT_SECTIONS_PASS
3329 && (*p
)->after_input_sections())
3331 else if (pass
== POSTPROCESSING_SECTIONS_PASS
3332 && (!(*p
)->after_input_sections()
3333 || (*p
)->type() == elfcpp::SHT_STRTAB
))
3335 else if (pass
== STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
3336 && (!(*p
)->after_input_sections()
3337 || (*p
)->type() != elfcpp::SHT_STRTAB
))
3340 if (!parameters
->incremental_update())
3342 off
= align_address(off
, (*p
)->addralign());
3343 (*p
)->set_file_offset(off
);
3344 (*p
)->finalize_data_size();
3348 // Incremental update: allocate file space from free list.
3349 (*p
)->pre_finalize_data_size();
3350 off_t current_size
= (*p
)->current_data_size();
3351 off
= this->allocate(current_size
, (*p
)->addralign(), startoff
);
3354 if (is_debugging_enabled(DEBUG_INCREMENTAL
))
3355 this->free_list_
.dump();
3356 gold_assert((*p
)->output_section() != NULL
);
3357 gold_fallback(_("out of patch space for section %s; "
3358 "relink with --incremental-full"),
3359 (*p
)->output_section()->name());
3361 (*p
)->set_file_offset(off
);
3362 (*p
)->finalize_data_size();
3363 if ((*p
)->data_size() > current_size
)
3365 gold_assert((*p
)->output_section() != NULL
);
3366 gold_fallback(_("%s: section changed size; "
3367 "relink with --incremental-full"),
3368 (*p
)->output_section()->name());
3370 gold_debug(DEBUG_INCREMENTAL
,
3371 "set_section_offsets: %08lx %08lx %s",
3372 static_cast<long>(off
),
3373 static_cast<long>((*p
)->data_size()),
3374 ((*p
)->output_section() != NULL
3375 ? (*p
)->output_section()->name() : "(special)"));
3378 off
+= (*p
)->data_size();
3382 // At this point the name must be set.
3383 if (pass
!= STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
)
3384 this->namepool_
.add((*p
)->name(), false, NULL
);
3389 // Set the section indexes of all the sections not associated with a
3393 Layout::set_section_indexes(unsigned int shndx
)
3395 for (Section_list::iterator p
= this->unattached_section_list_
.begin();
3396 p
!= this->unattached_section_list_
.end();
3399 if (!(*p
)->has_out_shndx())
3401 (*p
)->set_out_shndx(shndx
);
3408 // Set the section addresses according to the linker script. This is
3409 // only called when we see a SECTIONS clause. This returns the
3410 // program segment which should hold the file header and segment
3411 // headers, if any. It will return NULL if they should not be in a
3415 Layout::set_section_addresses_from_script(Symbol_table
* symtab
)
3417 Script_sections
* ss
= this->script_options_
->script_sections();
3418 gold_assert(ss
->saw_sections_clause());
3419 return this->script_options_
->set_section_addresses(symtab
, this);
3422 // Place the orphan sections in the linker script.
3425 Layout::place_orphan_sections_in_script()
3427 Script_sections
* ss
= this->script_options_
->script_sections();
3428 gold_assert(ss
->saw_sections_clause());
3430 // Place each orphaned output section in the script.
3431 for (Section_list::iterator p
= this->section_list_
.begin();
3432 p
!= this->section_list_
.end();
3435 if (!(*p
)->found_in_sections_clause())
3436 ss
->place_orphan(*p
);
3440 // Count the local symbols in the regular symbol table and the dynamic
3441 // symbol table, and build the respective string pools.
3444 Layout::count_local_symbols(const Task
* task
,
3445 const Input_objects
* input_objects
)
3447 // First, figure out an upper bound on the number of symbols we'll
3448 // be inserting into each pool. This helps us create the pools with
3449 // the right size, to avoid unnecessary hashtable resizing.
3450 unsigned int symbol_count
= 0;
3451 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3452 p
!= input_objects
->relobj_end();
3454 symbol_count
+= (*p
)->local_symbol_count();
3456 // Go from "upper bound" to "estimate." We overcount for two
3457 // reasons: we double-count symbols that occur in more than one
3458 // object file, and we count symbols that are dropped from the
3459 // output. Add it all together and assume we overcount by 100%.
3462 // We assume all symbols will go into both the sympool and dynpool.
3463 this->sympool_
.reserve(symbol_count
);
3464 this->dynpool_
.reserve(symbol_count
);
3466 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3467 p
!= input_objects
->relobj_end();
3470 Task_lock_obj
<Object
> tlo(task
, *p
);
3471 (*p
)->count_local_symbols(&this->sympool_
, &this->dynpool_
);
3475 // Create the symbol table sections. Here we also set the final
3476 // values of the symbols. At this point all the loadable sections are
3477 // fully laid out. SHNUM is the number of sections so far.
3480 Layout::create_symtab_sections(const Input_objects
* input_objects
,
3481 Symbol_table
* symtab
,
3487 if (parameters
->target().get_size() == 32)
3489 symsize
= elfcpp::Elf_sizes
<32>::sym_size
;
3492 else if (parameters
->target().get_size() == 64)
3494 symsize
= elfcpp::Elf_sizes
<64>::sym_size
;
3500 // Compute file offsets relative to the start of the symtab section.
3503 // Save space for the dummy symbol at the start of the section. We
3504 // never bother to write this out--it will just be left as zero.
3506 unsigned int local_symbol_index
= 1;
3508 // Add STT_SECTION symbols for each Output section which needs one.
3509 for (Section_list::iterator p
= this->section_list_
.begin();
3510 p
!= this->section_list_
.end();
3513 if (!(*p
)->needs_symtab_index())
3514 (*p
)->set_symtab_index(-1U);
3517 (*p
)->set_symtab_index(local_symbol_index
);
3518 ++local_symbol_index
;
3523 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3524 p
!= input_objects
->relobj_end();
3527 unsigned int index
= (*p
)->finalize_local_symbols(local_symbol_index
,
3529 off
+= (index
- local_symbol_index
) * symsize
;
3530 local_symbol_index
= index
;
3533 unsigned int local_symcount
= local_symbol_index
;
3534 gold_assert(static_cast<off_t
>(local_symcount
* symsize
) == off
);
3537 size_t dyn_global_index
;
3539 if (this->dynsym_section_
== NULL
)
3542 dyn_global_index
= 0;
3547 dyn_global_index
= this->dynsym_section_
->info();
3548 off_t locsize
= dyn_global_index
* this->dynsym_section_
->entsize();
3549 dynoff
= this->dynsym_section_
->offset() + locsize
;
3550 dyncount
= (this->dynsym_section_
->data_size() - locsize
) / symsize
;
3551 gold_assert(static_cast<off_t
>(dyncount
* symsize
)
3552 == this->dynsym_section_
->data_size() - locsize
);
3555 off_t global_off
= off
;
3556 off
= symtab
->finalize(off
, dynoff
, dyn_global_index
, dyncount
,
3557 &this->sympool_
, &local_symcount
);
3559 if (!parameters
->options().strip_all())
3561 this->sympool_
.set_string_offsets();
3563 const char* symtab_name
= this->namepool_
.add(".symtab", false, NULL
);
3564 Output_section
* osymtab
= this->make_output_section(symtab_name
,
3568 this->symtab_section_
= osymtab
;
3570 Output_section_data
* pos
= new Output_data_fixed_space(off
, align
,
3572 osymtab
->add_output_section_data(pos
);
3574 // We generate a .symtab_shndx section if we have more than
3575 // SHN_LORESERVE sections. Technically it is possible that we
3576 // don't need one, because it is possible that there are no
3577 // symbols in any of sections with indexes larger than
3578 // SHN_LORESERVE. That is probably unusual, though, and it is
3579 // easier to always create one than to compute section indexes
3580 // twice (once here, once when writing out the symbols).
3581 if (shnum
>= elfcpp::SHN_LORESERVE
)
3583 const char* symtab_xindex_name
= this->namepool_
.add(".symtab_shndx",
3585 Output_section
* osymtab_xindex
=
3586 this->make_output_section(symtab_xindex_name
,
3587 elfcpp::SHT_SYMTAB_SHNDX
, 0,
3588 ORDER_INVALID
, false);
3590 size_t symcount
= off
/ symsize
;
3591 this->symtab_xindex_
= new Output_symtab_xindex(symcount
);
3593 osymtab_xindex
->add_output_section_data(this->symtab_xindex_
);
3595 osymtab_xindex
->set_link_section(osymtab
);
3596 osymtab_xindex
->set_addralign(4);
3597 osymtab_xindex
->set_entsize(4);
3599 osymtab_xindex
->set_after_input_sections();
3601 // This tells the driver code to wait until the symbol table
3602 // has written out before writing out the postprocessing
3603 // sections, including the .symtab_shndx section.
3604 this->any_postprocessing_sections_
= true;
3607 const char* strtab_name
= this->namepool_
.add(".strtab", false, NULL
);
3608 Output_section
* ostrtab
= this->make_output_section(strtab_name
,
3613 Output_section_data
* pstr
= new Output_data_strtab(&this->sympool_
);
3614 ostrtab
->add_output_section_data(pstr
);
3617 if (!parameters
->incremental_update())
3618 symtab_off
= align_address(*poff
, align
);
3621 symtab_off
= this->allocate(off
, align
, *poff
);
3623 gold_fallback(_("out of patch space for symbol table; "
3624 "relink with --incremental-full"));
3625 gold_debug(DEBUG_INCREMENTAL
,
3626 "create_symtab_sections: %08lx %08lx .symtab",
3627 static_cast<long>(symtab_off
),
3628 static_cast<long>(off
));
3631 symtab
->set_file_offset(symtab_off
+ global_off
);
3632 osymtab
->set_file_offset(symtab_off
);
3633 osymtab
->finalize_data_size();
3634 osymtab
->set_link_section(ostrtab
);
3635 osymtab
->set_info(local_symcount
);
3636 osymtab
->set_entsize(symsize
);
3638 if (symtab_off
+ off
> *poff
)
3639 *poff
= symtab_off
+ off
;
3643 // Create the .shstrtab section, which holds the names of the
3644 // sections. At the time this is called, we have created all the
3645 // output sections except .shstrtab itself.
3648 Layout::create_shstrtab()
3650 // FIXME: We don't need to create a .shstrtab section if we are
3651 // stripping everything.
3653 const char* name
= this->namepool_
.add(".shstrtab", false, NULL
);
3655 Output_section
* os
= this->make_output_section(name
, elfcpp::SHT_STRTAB
, 0,
3656 ORDER_INVALID
, false);
3658 if (strcmp(parameters
->options().compress_debug_sections(), "none") != 0)
3660 // We can't write out this section until we've set all the
3661 // section names, and we don't set the names of compressed
3662 // output sections until relocations are complete. FIXME: With
3663 // the current names we use, this is unnecessary.
3664 os
->set_after_input_sections();
3667 Output_section_data
* posd
= new Output_data_strtab(&this->namepool_
);
3668 os
->add_output_section_data(posd
);
3673 // Create the section headers. SIZE is 32 or 64. OFF is the file
3677 Layout::create_shdrs(const Output_section
* shstrtab_section
, off_t
* poff
)
3679 Output_section_headers
* oshdrs
;
3680 oshdrs
= new Output_section_headers(this,
3681 &this->segment_list_
,
3682 &this->section_list_
,
3683 &this->unattached_section_list_
,
3687 if (!parameters
->incremental_update())
3688 off
= align_address(*poff
, oshdrs
->addralign());
3691 oshdrs
->pre_finalize_data_size();
3692 off
= this->allocate(oshdrs
->data_size(), oshdrs
->addralign(), *poff
);
3694 gold_fallback(_("out of patch space for section header table; "
3695 "relink with --incremental-full"));
3696 gold_debug(DEBUG_INCREMENTAL
,
3697 "create_shdrs: %08lx %08lx (section header table)",
3698 static_cast<long>(off
),
3699 static_cast<long>(off
+ oshdrs
->data_size()));
3701 oshdrs
->set_address_and_file_offset(0, off
);
3702 off
+= oshdrs
->data_size();
3705 this->section_headers_
= oshdrs
;
3708 // Count the allocated sections.
3711 Layout::allocated_output_section_count() const
3713 size_t section_count
= 0;
3714 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
3715 p
!= this->segment_list_
.end();
3717 section_count
+= (*p
)->output_section_count();
3718 return section_count
;
3721 // Create the dynamic symbol table.
3724 Layout::create_dynamic_symtab(const Input_objects
* input_objects
,
3725 Symbol_table
* symtab
,
3726 Output_section
** pdynstr
,
3727 unsigned int* plocal_dynamic_count
,
3728 std::vector
<Symbol
*>* pdynamic_symbols
,
3729 Versions
* pversions
)
3731 // Count all the symbols in the dynamic symbol table, and set the
3732 // dynamic symbol indexes.
3734 // Skip symbol 0, which is always all zeroes.
3735 unsigned int index
= 1;
3737 // Add STT_SECTION symbols for each Output section which needs one.
3738 for (Section_list::iterator p
= this->section_list_
.begin();
3739 p
!= this->section_list_
.end();
3742 if (!(*p
)->needs_dynsym_index())
3743 (*p
)->set_dynsym_index(-1U);
3746 (*p
)->set_dynsym_index(index
);
3751 // Count the local symbols that need to go in the dynamic symbol table,
3752 // and set the dynamic symbol indexes.
3753 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3754 p
!= input_objects
->relobj_end();
3757 unsigned int new_index
= (*p
)->set_local_dynsym_indexes(index
);
3761 unsigned int local_symcount
= index
;
3762 *plocal_dynamic_count
= local_symcount
;
3764 index
= symtab
->set_dynsym_indexes(index
, pdynamic_symbols
,
3765 &this->dynpool_
, pversions
);
3769 const int size
= parameters
->target().get_size();
3772 symsize
= elfcpp::Elf_sizes
<32>::sym_size
;
3775 else if (size
== 64)
3777 symsize
= elfcpp::Elf_sizes
<64>::sym_size
;
3783 // Create the dynamic symbol table section.
3785 Output_section
* dynsym
= this->choose_output_section(NULL
, ".dynsym",
3789 ORDER_DYNAMIC_LINKER
,
3792 // Check for NULL as a linker script may discard .dynsym.
3795 Output_section_data
* odata
= new Output_data_fixed_space(index
* symsize
,
3798 dynsym
->add_output_section_data(odata
);
3800 dynsym
->set_info(local_symcount
);
3801 dynsym
->set_entsize(symsize
);
3802 dynsym
->set_addralign(align
);
3804 this->dynsym_section_
= dynsym
;
3807 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
3810 odyn
->add_section_address(elfcpp::DT_SYMTAB
, dynsym
);
3811 odyn
->add_constant(elfcpp::DT_SYMENT
, symsize
);
3814 // If there are more than SHN_LORESERVE allocated sections, we
3815 // create a .dynsym_shndx section. It is possible that we don't
3816 // need one, because it is possible that there are no dynamic
3817 // symbols in any of the sections with indexes larger than
3818 // SHN_LORESERVE. This is probably unusual, though, and at this
3819 // time we don't know the actual section indexes so it is
3820 // inconvenient to check.
3821 if (this->allocated_output_section_count() >= elfcpp::SHN_LORESERVE
)
3823 Output_section
* dynsym_xindex
=
3824 this->choose_output_section(NULL
, ".dynsym_shndx",
3825 elfcpp::SHT_SYMTAB_SHNDX
,
3827 false, ORDER_DYNAMIC_LINKER
, false);
3829 if (dynsym_xindex
!= NULL
)
3831 this->dynsym_xindex_
= new Output_symtab_xindex(index
);
3833 dynsym_xindex
->add_output_section_data(this->dynsym_xindex_
);
3835 dynsym_xindex
->set_link_section(dynsym
);
3836 dynsym_xindex
->set_addralign(4);
3837 dynsym_xindex
->set_entsize(4);
3839 dynsym_xindex
->set_after_input_sections();
3841 // This tells the driver code to wait until the symbol table
3842 // has written out before writing out the postprocessing
3843 // sections, including the .dynsym_shndx section.
3844 this->any_postprocessing_sections_
= true;
3848 // Create the dynamic string table section.
3850 Output_section
* dynstr
= this->choose_output_section(NULL
, ".dynstr",
3854 ORDER_DYNAMIC_LINKER
,
3859 Output_section_data
* strdata
= new Output_data_strtab(&this->dynpool_
);
3860 dynstr
->add_output_section_data(strdata
);
3863 dynsym
->set_link_section(dynstr
);
3864 if (this->dynamic_section_
!= NULL
)
3865 this->dynamic_section_
->set_link_section(dynstr
);
3869 odyn
->add_section_address(elfcpp::DT_STRTAB
, dynstr
);
3870 odyn
->add_section_size(elfcpp::DT_STRSZ
, dynstr
);
3876 // Create the hash tables.
3878 if (strcmp(parameters
->options().hash_style(), "sysv") == 0
3879 || strcmp(parameters
->options().hash_style(), "both") == 0)
3881 unsigned char* phash
;
3882 unsigned int hashlen
;
3883 Dynobj::create_elf_hash_table(*pdynamic_symbols
, local_symcount
,
3886 Output_section
* hashsec
=
3887 this->choose_output_section(NULL
, ".hash", elfcpp::SHT_HASH
,
3888 elfcpp::SHF_ALLOC
, false,
3889 ORDER_DYNAMIC_LINKER
, false);
3891 Output_section_data
* hashdata
= new Output_data_const_buffer(phash
,
3895 if (hashsec
!= NULL
&& hashdata
!= NULL
)
3896 hashsec
->add_output_section_data(hashdata
);
3898 if (hashsec
!= NULL
)
3901 hashsec
->set_link_section(dynsym
);
3902 hashsec
->set_entsize(4);
3906 odyn
->add_section_address(elfcpp::DT_HASH
, hashsec
);
3909 if (strcmp(parameters
->options().hash_style(), "gnu") == 0
3910 || strcmp(parameters
->options().hash_style(), "both") == 0)
3912 unsigned char* phash
;
3913 unsigned int hashlen
;
3914 Dynobj::create_gnu_hash_table(*pdynamic_symbols
, local_symcount
,
3917 Output_section
* hashsec
=
3918 this->choose_output_section(NULL
, ".gnu.hash", elfcpp::SHT_GNU_HASH
,
3919 elfcpp::SHF_ALLOC
, false,
3920 ORDER_DYNAMIC_LINKER
, false);
3922 Output_section_data
* hashdata
= new Output_data_const_buffer(phash
,
3926 if (hashsec
!= NULL
&& hashdata
!= NULL
)
3927 hashsec
->add_output_section_data(hashdata
);
3929 if (hashsec
!= NULL
)
3932 hashsec
->set_link_section(dynsym
);
3934 // For a 64-bit target, the entries in .gnu.hash do not have
3935 // a uniform size, so we only set the entry size for a
3937 if (parameters
->target().get_size() == 32)
3938 hashsec
->set_entsize(4);
3941 odyn
->add_section_address(elfcpp::DT_GNU_HASH
, hashsec
);
3946 // Assign offsets to each local portion of the dynamic symbol table.
3949 Layout::assign_local_dynsym_offsets(const Input_objects
* input_objects
)
3951 Output_section
* dynsym
= this->dynsym_section_
;
3955 off_t off
= dynsym
->offset();
3957 // Skip the dummy symbol at the start of the section.
3958 off
+= dynsym
->entsize();
3960 for (Input_objects::Relobj_iterator p
= input_objects
->relobj_begin();
3961 p
!= input_objects
->relobj_end();
3964 unsigned int count
= (*p
)->set_local_dynsym_offset(off
);
3965 off
+= count
* dynsym
->entsize();
3969 // Create the version sections.
3972 Layout::create_version_sections(const Versions
* versions
,
3973 const Symbol_table
* symtab
,
3974 unsigned int local_symcount
,
3975 const std::vector
<Symbol
*>& dynamic_symbols
,
3976 const Output_section
* dynstr
)
3978 if (!versions
->any_defs() && !versions
->any_needs())
3981 switch (parameters
->size_and_endianness())
3983 #ifdef HAVE_TARGET_32_LITTLE
3984 case Parameters::TARGET_32_LITTLE
:
3985 this->sized_create_version_sections
<32, false>(versions
, symtab
,
3987 dynamic_symbols
, dynstr
);
3990 #ifdef HAVE_TARGET_32_BIG
3991 case Parameters::TARGET_32_BIG
:
3992 this->sized_create_version_sections
<32, true>(versions
, symtab
,
3994 dynamic_symbols
, dynstr
);
3997 #ifdef HAVE_TARGET_64_LITTLE
3998 case Parameters::TARGET_64_LITTLE
:
3999 this->sized_create_version_sections
<64, false>(versions
, symtab
,
4001 dynamic_symbols
, dynstr
);
4004 #ifdef HAVE_TARGET_64_BIG
4005 case Parameters::TARGET_64_BIG
:
4006 this->sized_create_version_sections
<64, true>(versions
, symtab
,
4008 dynamic_symbols
, dynstr
);
4016 // Create the version sections, sized version.
4018 template<int size
, bool big_endian
>
4020 Layout::sized_create_version_sections(
4021 const Versions
* versions
,
4022 const Symbol_table
* symtab
,
4023 unsigned int local_symcount
,
4024 const std::vector
<Symbol
*>& dynamic_symbols
,
4025 const Output_section
* dynstr
)
4027 Output_section
* vsec
= this->choose_output_section(NULL
, ".gnu.version",
4028 elfcpp::SHT_GNU_versym
,
4031 ORDER_DYNAMIC_LINKER
,
4034 // Check for NULL since a linker script may discard this section.
4037 unsigned char* vbuf
;
4039 versions
->symbol_section_contents
<size
, big_endian
>(symtab
,
4045 Output_section_data
* vdata
= new Output_data_const_buffer(vbuf
, vsize
, 2,
4048 vsec
->add_output_section_data(vdata
);
4049 vsec
->set_entsize(2);
4050 vsec
->set_link_section(this->dynsym_section_
);
4053 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
4054 if (odyn
!= NULL
&& vsec
!= NULL
)
4055 odyn
->add_section_address(elfcpp::DT_VERSYM
, vsec
);
4057 if (versions
->any_defs())
4059 Output_section
* vdsec
;
4060 vdsec
= this->choose_output_section(NULL
, ".gnu.version_d",
4061 elfcpp::SHT_GNU_verdef
,
4063 false, ORDER_DYNAMIC_LINKER
, false);
4067 unsigned char* vdbuf
;
4068 unsigned int vdsize
;
4069 unsigned int vdentries
;
4070 versions
->def_section_contents
<size
, big_endian
>(&this->dynpool_
,
4074 Output_section_data
* vddata
=
4075 new Output_data_const_buffer(vdbuf
, vdsize
, 4, "** version defs");
4077 vdsec
->add_output_section_data(vddata
);
4078 vdsec
->set_link_section(dynstr
);
4079 vdsec
->set_info(vdentries
);
4083 odyn
->add_section_address(elfcpp::DT_VERDEF
, vdsec
);
4084 odyn
->add_constant(elfcpp::DT_VERDEFNUM
, vdentries
);
4089 if (versions
->any_needs())
4091 Output_section
* vnsec
;
4092 vnsec
= this->choose_output_section(NULL
, ".gnu.version_r",
4093 elfcpp::SHT_GNU_verneed
,
4095 false, ORDER_DYNAMIC_LINKER
, false);
4099 unsigned char* vnbuf
;
4100 unsigned int vnsize
;
4101 unsigned int vnentries
;
4102 versions
->need_section_contents
<size
, big_endian
>(&this->dynpool_
,
4106 Output_section_data
* vndata
=
4107 new Output_data_const_buffer(vnbuf
, vnsize
, 4, "** version refs");
4109 vnsec
->add_output_section_data(vndata
);
4110 vnsec
->set_link_section(dynstr
);
4111 vnsec
->set_info(vnentries
);
4115 odyn
->add_section_address(elfcpp::DT_VERNEED
, vnsec
);
4116 odyn
->add_constant(elfcpp::DT_VERNEEDNUM
, vnentries
);
4122 // Create the .interp section and PT_INTERP segment.
4125 Layout::create_interp(const Target
* target
)
4127 gold_assert(this->interp_segment_
== NULL
);
4129 const char* interp
= parameters
->options().dynamic_linker();
4132 interp
= target
->dynamic_linker();
4133 gold_assert(interp
!= NULL
);
4136 size_t len
= strlen(interp
) + 1;
4138 Output_section_data
* odata
= new Output_data_const(interp
, len
, 1);
4140 Output_section
* osec
= this->choose_output_section(NULL
, ".interp",
4141 elfcpp::SHT_PROGBITS
,
4143 false, ORDER_INTERP
,
4146 osec
->add_output_section_data(odata
);
4149 // Add dynamic tags for the PLT and the dynamic relocs. This is
4150 // called by the target-specific code. This does nothing if not doing
4153 // USE_REL is true for REL relocs rather than RELA relocs.
4155 // If PLT_GOT is not NULL, then DT_PLTGOT points to it.
4157 // If PLT_REL is not NULL, it is used for DT_PLTRELSZ, and DT_JMPREL,
4158 // and we also set DT_PLTREL. We use PLT_REL's output section, since
4159 // some targets have multiple reloc sections in PLT_REL.
4161 // If DYN_REL is not NULL, it is used for DT_REL/DT_RELA,
4162 // DT_RELSZ/DT_RELASZ, DT_RELENT/DT_RELAENT. Again we use the output
4165 // If ADD_DEBUG is true, we add a DT_DEBUG entry when generating an
4169 Layout::add_target_dynamic_tags(bool use_rel
, const Output_data
* plt_got
,
4170 const Output_data
* plt_rel
,
4171 const Output_data_reloc_generic
* dyn_rel
,
4172 bool add_debug
, bool dynrel_includes_plt
)
4174 Output_data_dynamic
* odyn
= this->dynamic_data_
;
4178 if (plt_got
!= NULL
&& plt_got
->output_section() != NULL
)
4179 odyn
->add_section_address(elfcpp::DT_PLTGOT
, plt_got
);
4181 if (plt_rel
!= NULL
&& plt_rel
->output_section() != NULL
)
4183 odyn
->add_section_size(elfcpp::DT_PLTRELSZ
, plt_rel
->output_section());
4184 odyn
->add_section_address(elfcpp::DT_JMPREL
, plt_rel
->output_section());
4185 odyn
->add_constant(elfcpp::DT_PLTREL
,
4186 use_rel
? elfcpp::DT_REL
: elfcpp::DT_RELA
);
4189 if (dyn_rel
!= NULL
&& dyn_rel
->output_section() != NULL
)
4191 odyn
->add_section_address(use_rel
? elfcpp::DT_REL
: elfcpp::DT_RELA
,
4192 dyn_rel
->output_section());
4194 && plt_rel
->output_section() != NULL
4195 && dynrel_includes_plt
)
4196 odyn
->add_section_size(use_rel
? elfcpp::DT_RELSZ
: elfcpp::DT_RELASZ
,
4197 dyn_rel
->output_section(),
4198 plt_rel
->output_section());
4200 odyn
->add_section_size(use_rel
? elfcpp::DT_RELSZ
: elfcpp::DT_RELASZ
,
4201 dyn_rel
->output_section());
4202 const int size
= parameters
->target().get_size();
4207 rel_tag
= elfcpp::DT_RELENT
;
4209 rel_size
= Reloc_types
<elfcpp::SHT_REL
, 32, false>::reloc_size
;
4210 else if (size
== 64)
4211 rel_size
= Reloc_types
<elfcpp::SHT_REL
, 64, false>::reloc_size
;
4217 rel_tag
= elfcpp::DT_RELAENT
;
4219 rel_size
= Reloc_types
<elfcpp::SHT_RELA
, 32, false>::reloc_size
;
4220 else if (size
== 64)
4221 rel_size
= Reloc_types
<elfcpp::SHT_RELA
, 64, false>::reloc_size
;
4225 odyn
->add_constant(rel_tag
, rel_size
);
4227 if (parameters
->options().combreloc())
4229 size_t c
= dyn_rel
->relative_reloc_count();
4231 odyn
->add_constant((use_rel
4232 ? elfcpp::DT_RELCOUNT
4233 : elfcpp::DT_RELACOUNT
),
4238 if (add_debug
&& !parameters
->options().shared())
4240 // The value of the DT_DEBUG tag is filled in by the dynamic
4241 // linker at run time, and used by the debugger.
4242 odyn
->add_constant(elfcpp::DT_DEBUG
, 0);
4246 // Finish the .dynamic section and PT_DYNAMIC segment.
4249 Layout::finish_dynamic_section(const Input_objects
* input_objects
,
4250 const Symbol_table
* symtab
)
4252 if (!this->script_options_
->saw_phdrs_clause()
4253 && this->dynamic_section_
!= NULL
)
4255 Output_segment
* oseg
= this->make_output_segment(elfcpp::PT_DYNAMIC
,
4258 oseg
->add_output_section_to_nonload(this->dynamic_section_
,
4259 elfcpp::PF_R
| elfcpp::PF_W
);
4262 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
4266 for (Input_objects::Dynobj_iterator p
= input_objects
->dynobj_begin();
4267 p
!= input_objects
->dynobj_end();
4270 if (!(*p
)->is_needed() && (*p
)->as_needed())
4272 // This dynamic object was linked with --as-needed, but it
4277 odyn
->add_string(elfcpp::DT_NEEDED
, (*p
)->soname());
4280 if (parameters
->options().shared())
4282 const char* soname
= parameters
->options().soname();
4284 odyn
->add_string(elfcpp::DT_SONAME
, soname
);
4287 Symbol
* sym
= symtab
->lookup(parameters
->options().init());
4288 if (sym
!= NULL
&& sym
->is_defined() && !sym
->is_from_dynobj())
4289 odyn
->add_symbol(elfcpp::DT_INIT
, sym
);
4291 sym
= symtab
->lookup(parameters
->options().fini());
4292 if (sym
!= NULL
&& sym
->is_defined() && !sym
->is_from_dynobj())
4293 odyn
->add_symbol(elfcpp::DT_FINI
, sym
);
4295 // Look for .init_array, .preinit_array and .fini_array by checking
4297 for(Layout::Section_list::const_iterator p
= this->section_list_
.begin();
4298 p
!= this->section_list_
.end();
4300 switch((*p
)->type())
4302 case elfcpp::SHT_FINI_ARRAY
:
4303 odyn
->add_section_address(elfcpp::DT_FINI_ARRAY
, *p
);
4304 odyn
->add_section_size(elfcpp::DT_FINI_ARRAYSZ
, *p
);
4306 case elfcpp::SHT_INIT_ARRAY
:
4307 odyn
->add_section_address(elfcpp::DT_INIT_ARRAY
, *p
);
4308 odyn
->add_section_size(elfcpp::DT_INIT_ARRAYSZ
, *p
);
4310 case elfcpp::SHT_PREINIT_ARRAY
:
4311 odyn
->add_section_address(elfcpp::DT_PREINIT_ARRAY
, *p
);
4312 odyn
->add_section_size(elfcpp::DT_PREINIT_ARRAYSZ
, *p
);
4318 // Add a DT_RPATH entry if needed.
4319 const General_options::Dir_list
& rpath(parameters
->options().rpath());
4322 std::string rpath_val
;
4323 for (General_options::Dir_list::const_iterator p
= rpath
.begin();
4327 if (rpath_val
.empty())
4328 rpath_val
= p
->name();
4331 // Eliminate duplicates.
4332 General_options::Dir_list::const_iterator q
;
4333 for (q
= rpath
.begin(); q
!= p
; ++q
)
4334 if (q
->name() == p
->name())
4339 rpath_val
+= p
->name();
4344 odyn
->add_string(elfcpp::DT_RPATH
, rpath_val
);
4345 if (parameters
->options().enable_new_dtags())
4346 odyn
->add_string(elfcpp::DT_RUNPATH
, rpath_val
);
4349 // Look for text segments that have dynamic relocations.
4350 bool have_textrel
= false;
4351 if (!this->script_options_
->saw_sections_clause())
4353 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
4354 p
!= this->segment_list_
.end();
4357 if ((*p
)->type() == elfcpp::PT_LOAD
4358 && ((*p
)->flags() & elfcpp::PF_W
) == 0
4359 && (*p
)->has_dynamic_reloc())
4361 have_textrel
= true;
4368 // We don't know the section -> segment mapping, so we are
4369 // conservative and just look for readonly sections with
4370 // relocations. If those sections wind up in writable segments,
4371 // then we have created an unnecessary DT_TEXTREL entry.
4372 for (Section_list::const_iterator p
= this->section_list_
.begin();
4373 p
!= this->section_list_
.end();
4376 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0
4377 && ((*p
)->flags() & elfcpp::SHF_WRITE
) == 0
4378 && (*p
)->has_dynamic_reloc())
4380 have_textrel
= true;
4386 if (parameters
->options().filter() != NULL
)
4387 odyn
->add_string(elfcpp::DT_FILTER
, parameters
->options().filter());
4388 if (parameters
->options().any_auxiliary())
4390 for (options::String_set::const_iterator p
=
4391 parameters
->options().auxiliary_begin();
4392 p
!= parameters
->options().auxiliary_end();
4394 odyn
->add_string(elfcpp::DT_AUXILIARY
, *p
);
4397 // Add a DT_FLAGS entry if necessary.
4398 unsigned int flags
= 0;
4401 // Add a DT_TEXTREL for compatibility with older loaders.
4402 odyn
->add_constant(elfcpp::DT_TEXTREL
, 0);
4403 flags
|= elfcpp::DF_TEXTREL
;
4405 if (parameters
->options().text())
4406 gold_error(_("read-only segment has dynamic relocations"));
4407 else if (parameters
->options().warn_shared_textrel()
4408 && parameters
->options().shared())
4409 gold_warning(_("shared library text segment is not shareable"));
4411 if (parameters
->options().shared() && this->has_static_tls())
4412 flags
|= elfcpp::DF_STATIC_TLS
;
4413 if (parameters
->options().origin())
4414 flags
|= elfcpp::DF_ORIGIN
;
4415 if (parameters
->options().Bsymbolic())
4417 flags
|= elfcpp::DF_SYMBOLIC
;
4418 // Add DT_SYMBOLIC for compatibility with older loaders.
4419 odyn
->add_constant(elfcpp::DT_SYMBOLIC
, 0);
4421 if (parameters
->options().now())
4422 flags
|= elfcpp::DF_BIND_NOW
;
4424 odyn
->add_constant(elfcpp::DT_FLAGS
, flags
);
4427 if (parameters
->options().initfirst())
4428 flags
|= elfcpp::DF_1_INITFIRST
;
4429 if (parameters
->options().interpose())
4430 flags
|= elfcpp::DF_1_INTERPOSE
;
4431 if (parameters
->options().loadfltr())
4432 flags
|= elfcpp::DF_1_LOADFLTR
;
4433 if (parameters
->options().nodefaultlib())
4434 flags
|= elfcpp::DF_1_NODEFLIB
;
4435 if (parameters
->options().nodelete())
4436 flags
|= elfcpp::DF_1_NODELETE
;
4437 if (parameters
->options().nodlopen())
4438 flags
|= elfcpp::DF_1_NOOPEN
;
4439 if (parameters
->options().nodump())
4440 flags
|= elfcpp::DF_1_NODUMP
;
4441 if (!parameters
->options().shared())
4442 flags
&= ~(elfcpp::DF_1_INITFIRST
4443 | elfcpp::DF_1_NODELETE
4444 | elfcpp::DF_1_NOOPEN
);
4445 if (parameters
->options().origin())
4446 flags
|= elfcpp::DF_1_ORIGIN
;
4447 if (parameters
->options().now())
4448 flags
|= elfcpp::DF_1_NOW
;
4449 if (parameters
->options().Bgroup())
4450 flags
|= elfcpp::DF_1_GROUP
;
4452 odyn
->add_constant(elfcpp::DT_FLAGS_1
, flags
);
4455 // Set the size of the _DYNAMIC symbol table to be the size of the
4459 Layout::set_dynamic_symbol_size(const Symbol_table
* symtab
)
4461 Output_data_dynamic
* const odyn
= this->dynamic_data_
;
4464 odyn
->finalize_data_size();
4465 if (this->dynamic_symbol_
== NULL
)
4467 off_t data_size
= odyn
->data_size();
4468 const int size
= parameters
->target().get_size();
4470 symtab
->get_sized_symbol
<32>(this->dynamic_symbol_
)->set_symsize(data_size
);
4471 else if (size
== 64)
4472 symtab
->get_sized_symbol
<64>(this->dynamic_symbol_
)->set_symsize(data_size
);
4477 // The mapping of input section name prefixes to output section names.
4478 // In some cases one prefix is itself a prefix of another prefix; in
4479 // such a case the longer prefix must come first. These prefixes are
4480 // based on the GNU linker default ELF linker script.
4482 #define MAPPING_INIT(f, t) { f, sizeof(f) - 1, t, sizeof(t) - 1 }
4483 const Layout::Section_name_mapping
Layout::section_name_mapping
[] =
4485 MAPPING_INIT(".text.", ".text"),
4486 MAPPING_INIT(".rodata.", ".rodata"),
4487 MAPPING_INIT(".data.rel.ro.local", ".data.rel.ro.local"),
4488 MAPPING_INIT(".data.rel.ro", ".data.rel.ro"),
4489 MAPPING_INIT(".data.", ".data"),
4490 MAPPING_INIT(".bss.", ".bss"),
4491 MAPPING_INIT(".tdata.", ".tdata"),
4492 MAPPING_INIT(".tbss.", ".tbss"),
4493 MAPPING_INIT(".init_array.", ".init_array"),
4494 MAPPING_INIT(".fini_array.", ".fini_array"),
4495 MAPPING_INIT(".sdata.", ".sdata"),
4496 MAPPING_INIT(".sbss.", ".sbss"),
4497 // FIXME: In the GNU linker, .sbss2 and .sdata2 are handled
4498 // differently depending on whether it is creating a shared library.
4499 MAPPING_INIT(".sdata2.", ".sdata"),
4500 MAPPING_INIT(".sbss2.", ".sbss"),
4501 MAPPING_INIT(".lrodata.", ".lrodata"),
4502 MAPPING_INIT(".ldata.", ".ldata"),
4503 MAPPING_INIT(".lbss.", ".lbss"),
4504 MAPPING_INIT(".gcc_except_table.", ".gcc_except_table"),
4505 MAPPING_INIT(".gnu.linkonce.d.rel.ro.local.", ".data.rel.ro.local"),
4506 MAPPING_INIT(".gnu.linkonce.d.rel.ro.", ".data.rel.ro"),
4507 MAPPING_INIT(".gnu.linkonce.t.", ".text"),
4508 MAPPING_INIT(".gnu.linkonce.r.", ".rodata"),
4509 MAPPING_INIT(".gnu.linkonce.d.", ".data"),
4510 MAPPING_INIT(".gnu.linkonce.b.", ".bss"),
4511 MAPPING_INIT(".gnu.linkonce.s.", ".sdata"),
4512 MAPPING_INIT(".gnu.linkonce.sb.", ".sbss"),
4513 MAPPING_INIT(".gnu.linkonce.s2.", ".sdata"),
4514 MAPPING_INIT(".gnu.linkonce.sb2.", ".sbss"),
4515 MAPPING_INIT(".gnu.linkonce.wi.", ".debug_info"),
4516 MAPPING_INIT(".gnu.linkonce.td.", ".tdata"),
4517 MAPPING_INIT(".gnu.linkonce.tb.", ".tbss"),
4518 MAPPING_INIT(".gnu.linkonce.lr.", ".lrodata"),
4519 MAPPING_INIT(".gnu.linkonce.l.", ".ldata"),
4520 MAPPING_INIT(".gnu.linkonce.lb.", ".lbss"),
4521 MAPPING_INIT(".ARM.extab", ".ARM.extab"),
4522 MAPPING_INIT(".gnu.linkonce.armextab.", ".ARM.extab"),
4523 MAPPING_INIT(".ARM.exidx", ".ARM.exidx"),
4524 MAPPING_INIT(".gnu.linkonce.armexidx.", ".ARM.exidx"),
4528 const int Layout::section_name_mapping_count
=
4529 (sizeof(Layout::section_name_mapping
)
4530 / sizeof(Layout::section_name_mapping
[0]));
4532 // Choose the output section name to use given an input section name.
4533 // Set *PLEN to the length of the name. *PLEN is initialized to the
4537 Layout::output_section_name(const Relobj
* relobj
, const char* name
,
4540 // gcc 4.3 generates the following sorts of section names when it
4541 // needs a section name specific to a function:
4547 // .data.rel.local.FN
4549 // .data.rel.ro.local.FN
4556 // The GNU linker maps all of those to the part before the .FN,
4557 // except that .data.rel.local.FN is mapped to .data, and
4558 // .data.rel.ro.local.FN is mapped to .data.rel.ro. The sections
4559 // beginning with .data.rel.ro.local are grouped together.
4561 // For an anonymous namespace, the string FN can contain a '.'.
4563 // Also of interest: .rodata.strN.N, .rodata.cstN, both of which the
4564 // GNU linker maps to .rodata.
4566 // The .data.rel.ro sections are used with -z relro. The sections
4567 // are recognized by name. We use the same names that the GNU
4568 // linker does for these sections.
4570 // It is hard to handle this in a principled way, so we don't even
4571 // try. We use a table of mappings. If the input section name is
4572 // not found in the table, we simply use it as the output section
4575 const Section_name_mapping
* psnm
= section_name_mapping
;
4576 for (int i
= 0; i
< section_name_mapping_count
; ++i
, ++psnm
)
4578 if (strncmp(name
, psnm
->from
, psnm
->fromlen
) == 0)
4580 *plen
= psnm
->tolen
;
4585 // As an additional complication, .ctors sections are output in
4586 // either .ctors or .init_array sections, and .dtors sections are
4587 // output in either .dtors or .fini_array sections.
4588 if (is_prefix_of(".ctors.", name
) || is_prefix_of(".dtors.", name
))
4590 if (parameters
->options().ctors_in_init_array())
4593 return name
[1] == 'c' ? ".init_array" : ".fini_array";
4598 return name
[1] == 'c' ? ".ctors" : ".dtors";
4601 if (parameters
->options().ctors_in_init_array()
4602 && (strcmp(name
, ".ctors") == 0 || strcmp(name
, ".dtors") == 0))
4604 // To make .init_array/.fini_array work with gcc we must exclude
4605 // .ctors and .dtors sections from the crtbegin and crtend
4608 || (!Layout::match_file_name(relobj
, "crtbegin")
4609 && !Layout::match_file_name(relobj
, "crtend")))
4612 return name
[1] == 'c' ? ".init_array" : ".fini_array";
4619 // Return true if RELOBJ is an input file whose base name matches
4620 // FILE_NAME. The base name must have an extension of ".o", and must
4621 // be exactly FILE_NAME.o or FILE_NAME, one character, ".o". This is
4622 // to match crtbegin.o as well as crtbeginS.o without getting confused
4623 // by other possibilities. Overall matching the file name this way is
4624 // a dreadful hack, but the GNU linker does it in order to better
4625 // support gcc, and we need to be compatible.
4628 Layout::match_file_name(const Relobj
* relobj
, const char* match
)
4630 const std::string
& file_name(relobj
->name());
4631 const char* base_name
= lbasename(file_name
.c_str());
4632 size_t match_len
= strlen(match
);
4633 if (strncmp(base_name
, match
, match_len
) != 0)
4635 size_t base_len
= strlen(base_name
);
4636 if (base_len
!= match_len
+ 2 && base_len
!= match_len
+ 3)
4638 return memcmp(base_name
+ base_len
- 2, ".o", 2) == 0;
4641 // Check if a comdat group or .gnu.linkonce section with the given
4642 // NAME is selected for the link. If there is already a section,
4643 // *KEPT_SECTION is set to point to the existing section and the
4644 // function returns false. Otherwise, OBJECT, SHNDX, IS_COMDAT, and
4645 // IS_GROUP_NAME are recorded for this NAME in the layout object,
4646 // *KEPT_SECTION is set to the internal copy and the function returns
4650 Layout::find_or_add_kept_section(const std::string
& name
,
4655 Kept_section
** kept_section
)
4657 // It's normal to see a couple of entries here, for the x86 thunk
4658 // sections. If we see more than a few, we're linking a C++
4659 // program, and we resize to get more space to minimize rehashing.
4660 if (this->signatures_
.size() > 4
4661 && !this->resized_signatures_
)
4663 reserve_unordered_map(&this->signatures_
,
4664 this->number_of_input_files_
* 64);
4665 this->resized_signatures_
= true;
4668 Kept_section candidate
;
4669 std::pair
<Signatures::iterator
, bool> ins
=
4670 this->signatures_
.insert(std::make_pair(name
, candidate
));
4672 if (kept_section
!= NULL
)
4673 *kept_section
= &ins
.first
->second
;
4676 // This is the first time we've seen this signature.
4677 ins
.first
->second
.set_object(object
);
4678 ins
.first
->second
.set_shndx(shndx
);
4680 ins
.first
->second
.set_is_comdat();
4682 ins
.first
->second
.set_is_group_name();
4686 // We have already seen this signature.
4688 if (ins
.first
->second
.is_group_name())
4690 // We've already seen a real section group with this signature.
4691 // If the kept group is from a plugin object, and we're in the
4692 // replacement phase, accept the new one as a replacement.
4693 if (ins
.first
->second
.object() == NULL
4694 && parameters
->options().plugins()->in_replacement_phase())
4696 ins
.first
->second
.set_object(object
);
4697 ins
.first
->second
.set_shndx(shndx
);
4702 else if (is_group_name
)
4704 // This is a real section group, and we've already seen a
4705 // linkonce section with this signature. Record that we've seen
4706 // a section group, and don't include this section group.
4707 ins
.first
->second
.set_is_group_name();
4712 // We've already seen a linkonce section and this is a linkonce
4713 // section. These don't block each other--this may be the same
4714 // symbol name with different section types.
4719 // Store the allocated sections into the section list.
4722 Layout::get_allocated_sections(Section_list
* section_list
) const
4724 for (Section_list::const_iterator p
= this->section_list_
.begin();
4725 p
!= this->section_list_
.end();
4727 if (((*p
)->flags() & elfcpp::SHF_ALLOC
) != 0)
4728 section_list
->push_back(*p
);
4731 // Create an output segment.
4734 Layout::make_output_segment(elfcpp::Elf_Word type
, elfcpp::Elf_Word flags
)
4736 gold_assert(!parameters
->options().relocatable());
4737 Output_segment
* oseg
= new Output_segment(type
, flags
);
4738 this->segment_list_
.push_back(oseg
);
4740 if (type
== elfcpp::PT_TLS
)
4741 this->tls_segment_
= oseg
;
4742 else if (type
== elfcpp::PT_GNU_RELRO
)
4743 this->relro_segment_
= oseg
;
4744 else if (type
== elfcpp::PT_INTERP
)
4745 this->interp_segment_
= oseg
;
4750 // Return the file offset of the normal symbol table.
4753 Layout::symtab_section_offset() const
4755 if (this->symtab_section_
!= NULL
)
4756 return this->symtab_section_
->offset();
4760 // Return the section index of the normal symbol table. It may have
4761 // been stripped by the -s/--strip-all option.
4764 Layout::symtab_section_shndx() const
4766 if (this->symtab_section_
!= NULL
)
4767 return this->symtab_section_
->out_shndx();
4771 // Write out the Output_sections. Most won't have anything to write,
4772 // since most of the data will come from input sections which are
4773 // handled elsewhere. But some Output_sections do have Output_data.
4776 Layout::write_output_sections(Output_file
* of
) const
4778 for (Section_list::const_iterator p
= this->section_list_
.begin();
4779 p
!= this->section_list_
.end();
4782 if (!(*p
)->after_input_sections())
4787 // Write out data not associated with a section or the symbol table.
4790 Layout::write_data(const Symbol_table
* symtab
, Output_file
* of
) const
4792 if (!parameters
->options().strip_all())
4794 const Output_section
* symtab_section
= this->symtab_section_
;
4795 for (Section_list::const_iterator p
= this->section_list_
.begin();
4796 p
!= this->section_list_
.end();
4799 if ((*p
)->needs_symtab_index())
4801 gold_assert(symtab_section
!= NULL
);
4802 unsigned int index
= (*p
)->symtab_index();
4803 gold_assert(index
> 0 && index
!= -1U);
4804 off_t off
= (symtab_section
->offset()
4805 + index
* symtab_section
->entsize());
4806 symtab
->write_section_symbol(*p
, this->symtab_xindex_
, of
, off
);
4811 const Output_section
* dynsym_section
= this->dynsym_section_
;
4812 for (Section_list::const_iterator p
= this->section_list_
.begin();
4813 p
!= this->section_list_
.end();
4816 if ((*p
)->needs_dynsym_index())
4818 gold_assert(dynsym_section
!= NULL
);
4819 unsigned int index
= (*p
)->dynsym_index();
4820 gold_assert(index
> 0 && index
!= -1U);
4821 off_t off
= (dynsym_section
->offset()
4822 + index
* dynsym_section
->entsize());
4823 symtab
->write_section_symbol(*p
, this->dynsym_xindex_
, of
, off
);
4827 // Write out the Output_data which are not in an Output_section.
4828 for (Data_list::const_iterator p
= this->special_output_list_
.begin();
4829 p
!= this->special_output_list_
.end();
4834 // Write out the Output_sections which can only be written after the
4835 // input sections are complete.
4838 Layout::write_sections_after_input_sections(Output_file
* of
)
4840 // Determine the final section offsets, and thus the final output
4841 // file size. Note we finalize the .shstrab last, to allow the
4842 // after_input_section sections to modify their section-names before
4844 if (this->any_postprocessing_sections_
)
4846 off_t off
= this->output_file_size_
;
4847 off
= this->set_section_offsets(off
, POSTPROCESSING_SECTIONS_PASS
);
4849 // Now that we've finalized the names, we can finalize the shstrab.
4851 this->set_section_offsets(off
,
4852 STRTAB_AFTER_POSTPROCESSING_SECTIONS_PASS
);
4854 if (off
> this->output_file_size_
)
4857 this->output_file_size_
= off
;
4861 for (Section_list::const_iterator p
= this->section_list_
.begin();
4862 p
!= this->section_list_
.end();
4865 if ((*p
)->after_input_sections())
4869 this->section_headers_
->write(of
);
4872 // If the build ID requires computing a checksum, do so here, and
4873 // write it out. We compute a checksum over the entire file because
4874 // that is simplest.
4877 Layout::write_build_id(Output_file
* of
) const
4879 if (this->build_id_note_
== NULL
)
4882 const unsigned char* iv
= of
->get_input_view(0, this->output_file_size_
);
4884 unsigned char* ov
= of
->get_output_view(this->build_id_note_
->offset(),
4885 this->build_id_note_
->data_size());
4887 const char* style
= parameters
->options().build_id();
4888 if (strcmp(style
, "sha1") == 0)
4891 sha1_init_ctx(&ctx
);
4892 sha1_process_bytes(iv
, this->output_file_size_
, &ctx
);
4893 sha1_finish_ctx(&ctx
, ov
);
4895 else if (strcmp(style
, "md5") == 0)
4899 md5_process_bytes(iv
, this->output_file_size_
, &ctx
);
4900 md5_finish_ctx(&ctx
, ov
);
4905 of
->write_output_view(this->build_id_note_
->offset(),
4906 this->build_id_note_
->data_size(),
4909 of
->free_input_view(0, this->output_file_size_
, iv
);
4912 // Write out a binary file. This is called after the link is
4913 // complete. IN is the temporary output file we used to generate the
4914 // ELF code. We simply walk through the segments, read them from
4915 // their file offset in IN, and write them to their load address in
4916 // the output file. FIXME: with a bit more work, we could support
4917 // S-records and/or Intel hex format here.
4920 Layout::write_binary(Output_file
* in
) const
4922 gold_assert(parameters
->options().oformat_enum()
4923 == General_options::OBJECT_FORMAT_BINARY
);
4925 // Get the size of the binary file.
4926 uint64_t max_load_address
= 0;
4927 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
4928 p
!= this->segment_list_
.end();
4931 if ((*p
)->type() == elfcpp::PT_LOAD
&& (*p
)->filesz() > 0)
4933 uint64_t max_paddr
= (*p
)->paddr() + (*p
)->filesz();
4934 if (max_paddr
> max_load_address
)
4935 max_load_address
= max_paddr
;
4939 Output_file
out(parameters
->options().output_file_name());
4940 out
.open(max_load_address
);
4942 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
4943 p
!= this->segment_list_
.end();
4946 if ((*p
)->type() == elfcpp::PT_LOAD
&& (*p
)->filesz() > 0)
4948 const unsigned char* vin
= in
->get_input_view((*p
)->offset(),
4950 unsigned char* vout
= out
.get_output_view((*p
)->paddr(),
4952 memcpy(vout
, vin
, (*p
)->filesz());
4953 out
.write_output_view((*p
)->paddr(), (*p
)->filesz(), vout
);
4954 in
->free_input_view((*p
)->offset(), (*p
)->filesz(), vin
);
4961 // Print the output sections to the map file.
4964 Layout::print_to_mapfile(Mapfile
* mapfile
) const
4966 for (Segment_list::const_iterator p
= this->segment_list_
.begin();
4967 p
!= this->segment_list_
.end();
4969 (*p
)->print_sections_to_mapfile(mapfile
);
4972 // Print statistical information to stderr. This is used for --stats.
4975 Layout::print_stats() const
4977 this->namepool_
.print_stats("section name pool");
4978 this->sympool_
.print_stats("output symbol name pool");
4979 this->dynpool_
.print_stats("dynamic name pool");
4981 for (Section_list::const_iterator p
= this->section_list_
.begin();
4982 p
!= this->section_list_
.end();
4984 (*p
)->print_merge_stats();
4987 // Write_sections_task methods.
4989 // We can always run this task.
4992 Write_sections_task::is_runnable()
4997 // We need to unlock both OUTPUT_SECTIONS_BLOCKER and FINAL_BLOCKER
5001 Write_sections_task::locks(Task_locker
* tl
)
5003 tl
->add(this, this->output_sections_blocker_
);
5004 tl
->add(this, this->final_blocker_
);
5007 // Run the task--write out the data.
5010 Write_sections_task::run(Workqueue
*)
5012 this->layout_
->write_output_sections(this->of_
);
5015 // Write_data_task methods.
5017 // We can always run this task.
5020 Write_data_task::is_runnable()
5025 // We need to unlock FINAL_BLOCKER when finished.
5028 Write_data_task::locks(Task_locker
* tl
)
5030 tl
->add(this, this->final_blocker_
);
5033 // Run the task--write out the data.
5036 Write_data_task::run(Workqueue
*)
5038 this->layout_
->write_data(this->symtab_
, this->of_
);
5041 // Write_symbols_task methods.
5043 // We can always run this task.
5046 Write_symbols_task::is_runnable()
5051 // We need to unlock FINAL_BLOCKER when finished.
5054 Write_symbols_task::locks(Task_locker
* tl
)
5056 tl
->add(this, this->final_blocker_
);
5059 // Run the task--write out the symbols.
5062 Write_symbols_task::run(Workqueue
*)
5064 this->symtab_
->write_globals(this->sympool_
, this->dynpool_
,
5065 this->layout_
->symtab_xindex(),
5066 this->layout_
->dynsym_xindex(), this->of_
);
5069 // Write_after_input_sections_task methods.
5071 // We can only run this task after the input sections have completed.
5074 Write_after_input_sections_task::is_runnable()
5076 if (this->input_sections_blocker_
->is_blocked())
5077 return this->input_sections_blocker_
;
5081 // We need to unlock FINAL_BLOCKER when finished.
5084 Write_after_input_sections_task::locks(Task_locker
* tl
)
5086 tl
->add(this, this->final_blocker_
);
5092 Write_after_input_sections_task::run(Workqueue
*)
5094 this->layout_
->write_sections_after_input_sections(this->of_
);
5097 // Close_task_runner methods.
5099 // Run the task--close the file.
5102 Close_task_runner::run(Workqueue
*, const Task
*)
5104 // If we need to compute a checksum for the BUILD if, we do so here.
5105 this->layout_
->write_build_id(this->of_
);
5107 // If we've been asked to create a binary file, we do so here.
5108 if (this->options_
->oformat_enum() != General_options::OBJECT_FORMAT_ELF
)
5109 this->layout_
->write_binary(this->of_
);
5114 // Instantiate the templates we need. We could use the configure
5115 // script to restrict this to only the ones for implemented targets.
5117 #ifdef HAVE_TARGET_32_LITTLE
5120 Layout::init_fixed_output_section
<32, false>(
5122 elfcpp::Shdr
<32, false>& shdr
);
5125 #ifdef HAVE_TARGET_32_BIG
5128 Layout::init_fixed_output_section
<32, true>(
5130 elfcpp::Shdr
<32, true>& shdr
);
5133 #ifdef HAVE_TARGET_64_LITTLE
5136 Layout::init_fixed_output_section
<64, false>(
5138 elfcpp::Shdr
<64, false>& shdr
);
5141 #ifdef HAVE_TARGET_64_BIG
5144 Layout::init_fixed_output_section
<64, true>(
5146 elfcpp::Shdr
<64, true>& shdr
);
5149 #ifdef HAVE_TARGET_32_LITTLE
5152 Layout::layout
<32, false>(Sized_relobj_file
<32, false>* object
,
5155 const elfcpp::Shdr
<32, false>& shdr
,
5156 unsigned int, unsigned int, off_t
*);
5159 #ifdef HAVE_TARGET_32_BIG
5162 Layout::layout
<32, true>(Sized_relobj_file
<32, true>* object
,
5165 const elfcpp::Shdr
<32, true>& shdr
,
5166 unsigned int, unsigned int, off_t
*);
5169 #ifdef HAVE_TARGET_64_LITTLE
5172 Layout::layout
<64, false>(Sized_relobj_file
<64, false>* object
,
5175 const elfcpp::Shdr
<64, false>& shdr
,
5176 unsigned int, unsigned int, off_t
*);
5179 #ifdef HAVE_TARGET_64_BIG
5182 Layout::layout
<64, true>(Sized_relobj_file
<64, true>* object
,
5185 const elfcpp::Shdr
<64, true>& shdr
,
5186 unsigned int, unsigned int, off_t
*);
5189 #ifdef HAVE_TARGET_32_LITTLE
5192 Layout::layout_reloc
<32, false>(Sized_relobj_file
<32, false>* object
,
5193 unsigned int reloc_shndx
,
5194 const elfcpp::Shdr
<32, false>& shdr
,
5195 Output_section
* data_section
,
5196 Relocatable_relocs
* rr
);
5199 #ifdef HAVE_TARGET_32_BIG
5202 Layout::layout_reloc
<32, true>(Sized_relobj_file
<32, true>* object
,
5203 unsigned int reloc_shndx
,
5204 const elfcpp::Shdr
<32, true>& shdr
,
5205 Output_section
* data_section
,
5206 Relocatable_relocs
* rr
);
5209 #ifdef HAVE_TARGET_64_LITTLE
5212 Layout::layout_reloc
<64, false>(Sized_relobj_file
<64, false>* object
,
5213 unsigned int reloc_shndx
,
5214 const elfcpp::Shdr
<64, false>& shdr
,
5215 Output_section
* data_section
,
5216 Relocatable_relocs
* rr
);
5219 #ifdef HAVE_TARGET_64_BIG
5222 Layout::layout_reloc
<64, true>(Sized_relobj_file
<64, true>* object
,
5223 unsigned int reloc_shndx
,
5224 const elfcpp::Shdr
<64, true>& shdr
,
5225 Output_section
* data_section
,
5226 Relocatable_relocs
* rr
);
5229 #ifdef HAVE_TARGET_32_LITTLE
5232 Layout::layout_group
<32, false>(Symbol_table
* symtab
,
5233 Sized_relobj_file
<32, false>* object
,
5235 const char* group_section_name
,
5236 const char* signature
,
5237 const elfcpp::Shdr
<32, false>& shdr
,
5238 elfcpp::Elf_Word flags
,
5239 std::vector
<unsigned int>* shndxes
);
5242 #ifdef HAVE_TARGET_32_BIG
5245 Layout::layout_group
<32, true>(Symbol_table
* symtab
,
5246 Sized_relobj_file
<32, true>* object
,
5248 const char* group_section_name
,
5249 const char* signature
,
5250 const elfcpp::Shdr
<32, true>& shdr
,
5251 elfcpp::Elf_Word flags
,
5252 std::vector
<unsigned int>* shndxes
);
5255 #ifdef HAVE_TARGET_64_LITTLE
5258 Layout::layout_group
<64, false>(Symbol_table
* symtab
,
5259 Sized_relobj_file
<64, false>* object
,
5261 const char* group_section_name
,
5262 const char* signature
,
5263 const elfcpp::Shdr
<64, false>& shdr
,
5264 elfcpp::Elf_Word flags
,
5265 std::vector
<unsigned int>* shndxes
);
5268 #ifdef HAVE_TARGET_64_BIG
5271 Layout::layout_group
<64, true>(Symbol_table
* symtab
,
5272 Sized_relobj_file
<64, true>* object
,
5274 const char* group_section_name
,
5275 const char* signature
,
5276 const elfcpp::Shdr
<64, true>& shdr
,
5277 elfcpp::Elf_Word flags
,
5278 std::vector
<unsigned int>* shndxes
);
5281 #ifdef HAVE_TARGET_32_LITTLE
5284 Layout::layout_eh_frame
<32, false>(Sized_relobj_file
<32, false>* object
,
5285 const unsigned char* symbols
,
5287 const unsigned char* symbol_names
,
5288 off_t symbol_names_size
,
5290 const elfcpp::Shdr
<32, false>& shdr
,
5291 unsigned int reloc_shndx
,
5292 unsigned int reloc_type
,
5296 #ifdef HAVE_TARGET_32_BIG
5299 Layout::layout_eh_frame
<32, true>(Sized_relobj_file
<32, true>* object
,
5300 const unsigned char* symbols
,
5302 const unsigned char* symbol_names
,
5303 off_t symbol_names_size
,
5305 const elfcpp::Shdr
<32, true>& shdr
,
5306 unsigned int reloc_shndx
,
5307 unsigned int reloc_type
,
5311 #ifdef HAVE_TARGET_64_LITTLE
5314 Layout::layout_eh_frame
<64, false>(Sized_relobj_file
<64, false>* object
,
5315 const unsigned char* symbols
,
5317 const unsigned char* symbol_names
,
5318 off_t symbol_names_size
,
5320 const elfcpp::Shdr
<64, false>& shdr
,
5321 unsigned int reloc_shndx
,
5322 unsigned int reloc_type
,
5326 #ifdef HAVE_TARGET_64_BIG
5329 Layout::layout_eh_frame
<64, true>(Sized_relobj_file
<64, true>* object
,
5330 const unsigned char* symbols
,
5332 const unsigned char* symbol_names
,
5333 off_t symbol_names_size
,
5335 const elfcpp::Shdr
<64, true>& shdr
,
5336 unsigned int reloc_shndx
,
5337 unsigned int reloc_type
,
5341 #ifdef HAVE_TARGET_32_LITTLE
5344 Layout::add_to_gdb_index(bool is_type_unit
,
5345 Sized_relobj
<32, false>* object
,
5346 const unsigned char* symbols
,
5349 unsigned int reloc_shndx
,
5350 unsigned int reloc_type
);
5353 #ifdef HAVE_TARGET_32_BIG
5356 Layout::add_to_gdb_index(bool is_type_unit
,
5357 Sized_relobj
<32, true>* object
,
5358 const unsigned char* symbols
,
5361 unsigned int reloc_shndx
,
5362 unsigned int reloc_type
);
5365 #ifdef HAVE_TARGET_64_LITTLE
5368 Layout::add_to_gdb_index(bool is_type_unit
,
5369 Sized_relobj
<64, false>* object
,
5370 const unsigned char* symbols
,
5373 unsigned int reloc_shndx
,
5374 unsigned int reloc_type
);
5377 #ifdef HAVE_TARGET_64_BIG
5380 Layout::add_to_gdb_index(bool is_type_unit
,
5381 Sized_relobj
<64, true>* object
,
5382 const unsigned char* symbols
,
5385 unsigned int reloc_shndx
,
5386 unsigned int reloc_type
);
5389 } // End namespace gold.