1 /* linker.c -- BFD linker routines
2 Copyright (C) 1993-2024 Free Software Foundation, Inc.
3 Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20 MA 02110-1301, USA. */
21
22 #include "sysdep.h"
23 #include "bfd.h"
24 #include "libbfd.h"
25 #include "bfdlink.h"
26 #include "genlink.h"
27
28 /*
29 SECTION
30 Linker Functions
31
32 @cindex Linker
33 The linker uses three special entry points in the BFD target
34 vector. It is not necessary to write special routines for
35 these entry points when creating a new BFD back end, since
36 generic versions are provided. However, writing them can
37 speed up linking and make it use significantly less runtime
38 memory.
39
40 The first routine creates a hash table used by the other
41 routines. The second routine adds the symbols from an object
42 file to the hash table. The third routine takes all the
43 object files and links them together to create the output
44 file. These routines are designed so that the linker proper
45 does not need to know anything about the symbols in the object
46 files that it is linking. The linker merely arranges the
47 sections as directed by the linker script and lets BFD handle
48 the details of symbols and relocs.
49
50 The second routine and third routines are passed a pointer to
51 a <<struct bfd_link_info>> structure (defined in
52 <<bfdlink.h>>) which holds information relevant to the link,
53 including the linker hash table (which was created by the
54 first routine) and a set of callback functions to the linker
55 proper.
56
57 The generic linker routines are in <<linker.c>>, and use the
58 header file <<genlink.h>>. As of this writing, the only back
59 ends which have implemented versions of these routines are
60 a.out (in <<aoutx.h>>) and ECOFF (in <<ecoff.c>>). The a.out
61 routines are used as examples throughout this section.
62
63 @menu
64 @* Creating a Linker Hash Table::
65 @* Adding Symbols to the Hash Table::
66 @* Performing the Final Link::
67 @end menu
68
69 INODE
70 Creating a Linker Hash Table, Adding Symbols to the Hash Table, Linker Functions, Linker Functions
71 SUBSECTION
72 Creating a linker hash table
73
74 @cindex _bfd_link_hash_table_create in target vector
75 @cindex target vector (_bfd_link_hash_table_create)
76 The linker routines must create a hash table, which must be
77 derived from <<struct bfd_link_hash_table>> described in
78 <<bfdlink.c>>. @xref{Hash Tables}, for information on how to
79 create a derived hash table. This entry point is called using
80 the target vector of the linker output file.
81
82 The <<_bfd_link_hash_table_create>> entry point must allocate
83 and initialize an instance of the desired hash table. If the
84 back end does not require any additional information to be
85 stored with the entries in the hash table, the entry point may
86 simply create a <<struct bfd_link_hash_table>>. Most likely,
87 however, some additional information will be needed.
88
89 For example, with each entry in the hash table the a.out
90 linker keeps the index the symbol has in the final output file
91 (this index number is used so that when doing a relocatable
92 link the symbol index used in the output file can be quickly
93 filled in when copying over a reloc). The a.out linker code
94 defines the required structures and functions for a hash table
95 derived from <<struct bfd_link_hash_table>>. The a.out linker
96 hash table is created by the function
97 <<NAME(aout,link_hash_table_create)>>; it simply allocates
98 space for the hash table, initializes it, and returns a
99 pointer to it.
100
101 When writing the linker routines for a new back end, you will
102 generally not know exactly which fields will be required until
103 you have finished. You should simply create a new hash table
104 which defines no additional fields, and then simply add fields
105 as they become necessary.
106
107 INODE
108 Adding Symbols to the Hash Table, Performing the Final Link, Creating a Linker Hash Table, Linker Functions
109 SUBSECTION
110 Adding symbols to the hash table
111
112 @cindex _bfd_link_add_symbols in target vector
113 @cindex target vector (_bfd_link_add_symbols)
114 The linker proper will call the <<_bfd_link_add_symbols>>
115 entry point for each object file or archive which is to be
116 linked (typically these are the files named on the command
117 line, but some may also come from the linker script). The
118 entry point is responsible for examining the file. For an
119 object file, BFD must add any relevant symbol information to
120 the hash table. For an archive, BFD must determine which
121 elements of the archive should be used and adding them to the
122 link.
123
124 The a.out version of this entry point is
125 <<NAME(aout,link_add_symbols)>>.
126
127 @menu
128 @* Differing file formats::
129 @* Adding symbols from an object file::
130 @* Adding symbols from an archive::
131 @end menu
132
133 INODE
134 Differing file formats, Adding symbols from an object file, Adding Symbols to the Hash Table, Adding Symbols to the Hash Table
135 SUBSUBSECTION
136 Differing file formats
137
138 Normally all the files involved in a link will be of the same
139 format, but it is also possible to link together different
140 format object files, and the back end must support that. The
141 <<_bfd_link_add_symbols>> entry point is called via the target
142 vector of the file to be added. This has an important
143 consequence: the function may not assume that the hash table
144 is the type created by the corresponding
145 <<_bfd_link_hash_table_create>> vector. All the
146 <<_bfd_link_add_symbols>> function can assume about the hash
147 table is that it is derived from <<struct
148 bfd_link_hash_table>>.
149
150 Sometimes the <<_bfd_link_add_symbols>> function must store
151 some information in the hash table entry to be used by the
152 <<_bfd_final_link>> function. In such a case the output bfd
153 xvec must be checked to make sure that the hash table was
154 created by an object file of the same format.
155
156 The <<_bfd_final_link>> routine must be prepared to handle a
157 hash entry without any extra information added by the
158 <<_bfd_link_add_symbols>> function. A hash entry without
159 extra information will also occur when the linker script
160 directs the linker to create a symbol. Note that, regardless
161 of how a hash table entry is added, all the fields will be
162 initialized to some sort of null value by the hash table entry
163 initialization function.
164
165 See <<ecoff_link_add_externals>> for an example of how to
166 check the output bfd before saving information (in this
167 case, the ECOFF external symbol debugging information) in a
168 hash table entry.
169
170 INODE
171 Adding symbols from an object file, Adding symbols from an archive, Differing file formats, Adding Symbols to the Hash Table
172 SUBSUBSECTION
173 Adding symbols from an object file
174
175 When the <<_bfd_link_add_symbols>> routine is passed an object
176 file, it must add all externally visible symbols in that
177 object file to the hash table. The actual work of adding the
178 symbol to the hash table is normally handled by the function
179 <<_bfd_generic_link_add_one_symbol>>. The
180 <<_bfd_link_add_symbols>> routine is responsible for reading
181 all the symbols from the object file and passing the correct
182 information to <<_bfd_generic_link_add_one_symbol>>.
183
184 The <<_bfd_link_add_symbols>> routine should not use
185 <<bfd_canonicalize_symtab>> to read the symbols. The point of
186 providing this routine is to avoid the overhead of converting
187 the symbols into generic <<asymbol>> structures.
188
189 @findex _bfd_generic_link_add_one_symbol
190 <<_bfd_generic_link_add_one_symbol>> handles the details of
191 combining common symbols, warning about multiple definitions,
192 and so forth. It takes arguments which describe the symbol to
193 add, notably symbol flags, a section, and an offset. The
194 symbol flags include such things as <<BSF_WEAK>> or
195 <<BSF_INDIRECT>>. The section is a section in the object
196 file, or something like <<bfd_und_section_ptr>> for an undefined
197 symbol or <<bfd_com_section_ptr>> for a common symbol.
198
199 If the <<_bfd_final_link>> routine is also going to need to
200 read the symbol information, the <<_bfd_link_add_symbols>>
201 routine should save it somewhere attached to the object file
202 BFD. However, the information should only be saved if the
203 <<keep_memory>> field of the <<info>> argument is TRUE, so
204 that the <<-no-keep-memory>> linker switch is effective.
205
206 The a.out function which adds symbols from an object file is
207 <<aout_link_add_object_symbols>>, and most of the interesting
208 work is in <<aout_link_add_symbols>>. The latter saves
209 pointers to the hash tables entries created by
210 <<_bfd_generic_link_add_one_symbol>> indexed by symbol number,
211 so that the <<_bfd_final_link>> routine does not have to call
212 the hash table lookup routine to locate the entry.
213
214 INODE
215 Adding symbols from an archive, , Adding symbols from an object file, Adding Symbols to the Hash Table
216 SUBSUBSECTION
217 Adding symbols from an archive
218
219 When the <<_bfd_link_add_symbols>> routine is passed an
220 archive, it must look through the symbols defined by the
221 archive and decide which elements of the archive should be
222 included in the link. For each such element it must call the
223 <<add_archive_element>> linker callback, and it must add the
224 symbols from the object file to the linker hash table. (The
225 callback may in fact indicate that a replacement BFD should be
226 used, in which case the symbols from that BFD should be added
227 to the linker hash table instead.)
228
229 @findex _bfd_generic_link_add_archive_symbols
230 In most cases the work of looking through the symbols in the
231 archive should be done by the
232 <<_bfd_generic_link_add_archive_symbols>> function.
233 <<_bfd_generic_link_add_archive_symbols>> is passed a function
234 to call to make the final decision about adding an archive
235 element to the link and to do the actual work of adding the
236 symbols to the linker hash table. If the element is to
237 be included, the <<add_archive_element>> linker callback
238 routine must be called with the element as an argument, and
239 the element's symbols must be added to the linker hash table
240 just as though the element had itself been passed to the
241 <<_bfd_link_add_symbols>> function.
242
243 When the a.out <<_bfd_link_add_symbols>> function receives an
244 archive, it calls <<_bfd_generic_link_add_archive_symbols>>
245 passing <<aout_link_check_archive_element>> as the function
246 argument. <<aout_link_check_archive_element>> calls
247 <<aout_link_check_ar_symbols>>. If the latter decides to add
248 the element (an element is only added if it provides a real,
249 non-common, definition for a previously undefined or common
250 symbol) it calls the <<add_archive_element>> callback and then
251 <<aout_link_check_archive_element>> calls
252 <<aout_link_add_symbols>> to actually add the symbols to the
253 linker hash table - possibly those of a substitute BFD, if the
254 <<add_archive_element>> callback avails itself of that option.
255
256 The ECOFF back end is unusual in that it does not normally
257 call <<_bfd_generic_link_add_archive_symbols>>, because ECOFF
258 archives already contain a hash table of symbols. The ECOFF
259 back end searches the archive itself to avoid the overhead of
260 creating a new hash table.
261
262 INODE
263 Performing the Final Link, , Adding Symbols to the Hash Table, Linker Functions
264 SUBSECTION
265 Performing the final link
266
267 @cindex _bfd_link_final_link in target vector
268 @cindex target vector (_bfd_final_link)
269 When all the input files have been processed, the linker calls
270 the <<_bfd_final_link>> entry point of the output BFD. This
271 routine is responsible for producing the final output file,
272 which has several aspects. It must relocate the contents of
273 the input sections and copy the data into the output sections.
274 It must build an output symbol table including any local
275 symbols from the input files and the global symbols from the
276 hash table. When producing relocatable output, it must
277 modify the input relocs and write them into the output file.
278 There may also be object format dependent work to be done.
279
280 The linker will also call the <<write_object_contents>> entry
281 point when the BFD is closed. The two entry points must work
282 together in order to produce the correct output file.
283
284 The details of how this works are inevitably dependent upon
285 the specific object file format. The a.out
286 <<_bfd_final_link>> routine is <<NAME(aout,final_link)>>.
287
288 @menu
289 @* Information provided by the linker::
290 @* Relocating the section contents::
291 @* Writing the symbol table::
292 @end menu
293
294 INODE
295 Information provided by the linker, Relocating the section contents, Performing the Final Link, Performing the Final Link
296 SUBSUBSECTION
297 Information provided by the linker
298
299 Before the linker calls the <<_bfd_final_link>> entry point,
300 it sets up some data structures for the function to use.
301
302 The <<input_bfds>> field of the <<bfd_link_info>> structure
303 will point to a list of all the input files included in the
304 link. These files are linked through the <<link.next>> field
305 of the <<bfd>> structure.
306
307 Each section in the output file will have a list of
308 <<link_order>> structures attached to the <<map_head.link_order>>
309 field (the <<link_order>> structure is defined in
310 <<bfdlink.h>>). These structures describe how to create the
311 contents of the output section in terms of the contents of
312 various input sections, fill constants, and, eventually, other
313 types of information. They also describe relocs that must be
314 created by the BFD backend, but do not correspond to any input
315 file; this is used to support -Ur, which builds constructors
316 while generating a relocatable object file.
317
318 INODE
319 Relocating the section contents, Writing the symbol table, Information provided by the linker, Performing the Final Link
320 SUBSUBSECTION
321 Relocating the section contents
322
323 The <<_bfd_final_link>> function should look through the
324 <<link_order>> structures attached to each section of the
325 output file. Each <<link_order>> structure should either be
326 handled specially, or it should be passed to the function
327 <<_bfd_default_link_order>> which will do the right thing
328 (<<_bfd_default_link_order>> is defined in <<linker.c>>).
329
330 For efficiency, a <<link_order>> of type
331 <<bfd_indirect_link_order>> whose associated section belongs
332 to a BFD of the same format as the output BFD must be handled
333 specially. This type of <<link_order>> describes part of an
334 output section in terms of a section belonging to one of the
335 input files. The <<_bfd_final_link>> function should read the
336 contents of the section and any associated relocs, apply the
337 relocs to the section contents, and write out the modified
338 section contents. If performing a relocatable link, the
339 relocs themselves must also be modified and written out.
340
341 @findex _bfd_relocate_contents
342 @findex _bfd_final_link_relocate
343 The functions <<_bfd_relocate_contents>> and
344 <<_bfd_final_link_relocate>> provide some general support for
345 performing the actual relocations, notably overflow checking.
346 Their arguments include information about the symbol the
347 relocation is against and a <<reloc_howto_type>> argument
348 which describes the relocation to perform. These functions
349 are defined in <<reloc.c>>.
350
351 The a.out function which handles reading, relocating, and
352 writing section contents is <<aout_link_input_section>>. The
353 actual relocation is done in <<aout_link_input_section_std>>
354 and <<aout_link_input_section_ext>>.
355
356 INODE
357 Writing the symbol table, , Relocating the section contents, Performing the Final Link
358 SUBSUBSECTION
359 Writing the symbol table
360
361 The <<_bfd_final_link>> function must gather all the symbols
362 in the input files and write them out. It must also write out
363 all the symbols in the global hash table. This must be
364 controlled by the <<strip>> and <<discard>> fields of the
365 <<bfd_link_info>> structure.
366
367 The local symbols of the input files will not have been
368 entered into the linker hash table. The <<_bfd_final_link>>
369 routine must consider each input file and include the symbols
370 in the output file. It may be convenient to do this when
371 looking through the <<link_order>> structures, or it may be
372 done by stepping through the <<input_bfds>> list.
373
374 The <<_bfd_final_link>> routine must also traverse the global
375 hash table to gather all the externally visible symbols. It
376 is possible that most of the externally visible symbols may be
377 written out when considering the symbols of each input file,
378 but it is still necessary to traverse the hash table since the
379 linker script may have defined some symbols that are not in
380 any of the input files.
381
382 The <<strip>> field of the <<bfd_link_info>> structure
383 controls which symbols are written out. The possible values
384 are listed in <<bfdlink.h>>. If the value is <<strip_some>>,
385 then the <<keep_hash>> field of the <<bfd_link_info>>
386 structure is a hash table of symbols to keep; each symbol
387 should be looked up in this hash table, and only symbols which
388 are present should be included in the output file.
389
390 If the <<strip>> field of the <<bfd_link_info>> structure
391 permits local symbols to be written out, the <<discard>> field
392 is used to further controls which local symbols are included
393 in the output file. If the value is <<discard_l>>, then all
394 local symbols which begin with a certain prefix are discarded;
395 this is controlled by the <<bfd_is_local_label_name>> entry point.
396
397 The a.out backend handles symbols by calling
398 <<aout_link_write_symbols>> on each input BFD and then
399 traversing the global hash table with the function
400 <<aout_link_write_other_symbol>>. It builds a string table
401 while writing out the symbols, which is written to the output
402 file at the end of <<NAME(aout,final_link)>>.
403 */
404
405 static bool generic_link_add_object_symbols
406 (bfd *, struct bfd_link_info *);
407 static bool generic_link_check_archive_element
408 (bfd *, struct bfd_link_info *, struct bfd_link_hash_entry *, const char *,
409 bool *);
410 static bool generic_link_add_symbol_list
411 (bfd *, struct bfd_link_info *, bfd_size_type count, asymbol **);
412 static bool generic_add_output_symbol
413 (bfd *, size_t *psymalloc, asymbol *);
414 static bool default_data_link_order
415 (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *);
416 static bool default_indirect_link_order
417 (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *,
418 bool);
419
420 /* The link hash table structure is defined in bfdlink.h. It provides
421 a base hash table which the backend specific hash tables are built
422 upon. */
423
424 /* Routine to create an entry in the link hash table. */
425
426 struct bfd_hash_entry *
_bfd_link_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)427 _bfd_link_hash_newfunc (struct bfd_hash_entry *entry,
428 struct bfd_hash_table *table,
429 const char *string)
430 {
431 /* Allocate the structure if it has not already been allocated by a
432 subclass. */
433 if (entry == NULL)
434 {
435 entry = (struct bfd_hash_entry *)
436 bfd_hash_allocate (table, sizeof (struct bfd_link_hash_entry));
437 if (entry == NULL)
438 return entry;
439 }
440
441 /* Call the allocation method of the superclass. */
442 entry = bfd_hash_newfunc (entry, table, string);
443 if (entry)
444 {
445 struct bfd_link_hash_entry *h = (struct bfd_link_hash_entry *) entry;
446
447 /* Initialize the local fields. */
448 memset ((char *) &h->root + sizeof (h->root), 0,
449 sizeof (*h) - sizeof (h->root));
450 }
451
452 return entry;
453 }
454
455 /* Initialize a link hash table. The BFD argument is the one
456 responsible for creating this table. */
457
458 bool
_bfd_link_hash_table_init(struct bfd_link_hash_table * table,bfd * abfd ATTRIBUTE_UNUSED,struct bfd_hash_entry * (* newfunc)(struct bfd_hash_entry *,struct bfd_hash_table *,const char *),unsigned int entsize)459 _bfd_link_hash_table_init
460 (struct bfd_link_hash_table *table,
461 bfd *abfd ATTRIBUTE_UNUSED,
462 struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
463 struct bfd_hash_table *,
464 const char *),
465 unsigned int entsize)
466 {
467 bool ret;
468
469 BFD_ASSERT (!abfd->is_linker_output && !abfd->link.hash);
470 table->undefs = NULL;
471 table->undefs_tail = NULL;
472 table->type = bfd_link_generic_hash_table;
473
474 ret = bfd_hash_table_init (&table->table, newfunc, entsize);
475 if (ret)
476 {
477 /* Arrange for destruction of this hash table on closing ABFD. */
478 table->hash_table_free = _bfd_generic_link_hash_table_free;
479 abfd->link.hash = table;
480 abfd->is_linker_output = true;
481 }
482 return ret;
483 }
484
485 /* Look up a symbol in a link hash table. If follow is TRUE, we
486 follow bfd_link_hash_indirect and bfd_link_hash_warning links to
487 the real symbol.
488
489 .{* Return TRUE if the symbol described by a linker hash entry H
490 . is going to be absolute. Linker-script defined symbols can be
491 . converted from absolute to section-relative ones late in the
492 . link. Use this macro to correctly determine whether the symbol
493 . will actually end up absolute in output. *}
494 .#define bfd_is_abs_symbol(H) \
495 . (((H)->type == bfd_link_hash_defined \
496 . || (H)->type == bfd_link_hash_defweak) \
497 . && bfd_is_abs_section ((H)->u.def.section) \
498 . && !(H)->rel_from_abs)
499 .
500 */
501
502 struct bfd_link_hash_entry *
bfd_link_hash_lookup(struct bfd_link_hash_table * table,const char * string,bool create,bool copy,bool follow)503 bfd_link_hash_lookup (struct bfd_link_hash_table *table,
504 const char *string,
505 bool create,
506 bool copy,
507 bool follow)
508 {
509 struct bfd_link_hash_entry *ret;
510
511 if (table == NULL || string == NULL)
512 return NULL;
513
514 ret = ((struct bfd_link_hash_entry *)
515 bfd_hash_lookup (&table->table, string, create, copy));
516
517 if (follow && ret != NULL)
518 {
519 while (ret->type == bfd_link_hash_indirect
520 || ret->type == bfd_link_hash_warning)
521 ret = ret->u.i.link;
522 }
523
524 return ret;
525 }
526
527 /* Look up a symbol in the main linker hash table if the symbol might
528 be wrapped. This should only be used for references to an
529 undefined symbol, not for definitions of a symbol. */
530
531 struct bfd_link_hash_entry *
bfd_wrapped_link_hash_lookup(bfd * abfd,struct bfd_link_info * info,const char * string,bool create,bool copy,bool follow)532 bfd_wrapped_link_hash_lookup (bfd *abfd,
533 struct bfd_link_info *info,
534 const char *string,
535 bool create,
536 bool copy,
537 bool follow)
538 {
539 size_t amt;
540
541 if (info->wrap_hash != NULL)
542 {
543 const char *l;
544 char prefix = '\0';
545
546 l = string;
547 if (*l
548 && (*l == bfd_get_symbol_leading_char (abfd)
549 || *l == info->wrap_char))
550 {
551 prefix = *l;
552 ++l;
553 }
554
555 #undef WRAP
556 #define WRAP "__wrap_"
557
558 if (bfd_hash_lookup (info->wrap_hash, l, false, false) != NULL)
559 {
560 char *n;
561 struct bfd_link_hash_entry *h;
562
563 /* This symbol is being wrapped. We want to replace all
564 references to SYM with references to __wrap_SYM. */
565
566 amt = strlen (l) + sizeof WRAP + 1;
567 n = (char *) bfd_malloc (amt);
568 if (n == NULL)
569 return NULL;
570
571 n[0] = prefix;
572 n[1] = '\0';
573 strcat (n, WRAP);
574 strcat (n, l);
575 h = bfd_link_hash_lookup (info->hash, n, create, true, follow);
576 free (n);
577 return h;
578 }
579
580 #undef REAL
581 #define REAL "__real_"
582
583 if (*l == '_'
584 && startswith (l, REAL)
585 && bfd_hash_lookup (info->wrap_hash, l + sizeof REAL - 1,
586 false, false) != NULL)
587 {
588 char *n;
589 struct bfd_link_hash_entry *h;
590
591 /* This is a reference to __real_SYM, where SYM is being
592 wrapped. We want to replace all references to __real_SYM
593 with references to SYM. */
594
595 amt = strlen (l + sizeof REAL - 1) + 2;
596 n = (char *) bfd_malloc (amt);
597 if (n == NULL)
598 return NULL;
599
600 n[0] = prefix;
601 n[1] = '\0';
602 strcat (n, l + sizeof REAL - 1);
603 h = bfd_link_hash_lookup (info->hash, n, create, true, follow);
604 if (h != NULL)
605 h->ref_real = 1;
606 free (n);
607 return h;
608 }
609
610 #undef REAL
611 }
612
613 return bfd_link_hash_lookup (info->hash, string, create, copy, follow);
614 }
615
616 /* If H is a wrapped symbol, ie. the symbol name starts with "__wrap_"
617 and the remainder is found in wrap_hash, return the real symbol. */
618
619 struct bfd_link_hash_entry *
unwrap_hash_lookup(struct bfd_link_info * info,bfd * input_bfd,struct bfd_link_hash_entry * h)620 unwrap_hash_lookup (struct bfd_link_info *info,
621 bfd *input_bfd,
622 struct bfd_link_hash_entry *h)
623 {
624 const char *l = h->root.string;
625
626 if (*l
627 && (*l == bfd_get_symbol_leading_char (input_bfd)
628 || *l == info->wrap_char))
629 ++l;
630
631 if (startswith (l, WRAP))
632 {
633 l += sizeof WRAP - 1;
634
635 if (bfd_hash_lookup (info->wrap_hash, l, false, false) != NULL)
636 {
637 char save = 0;
638 if (l - (sizeof WRAP - 1) != h->root.string)
639 {
640 --l;
641 save = *l;
642 *(char *) l = *h->root.string;
643 }
644 h = bfd_link_hash_lookup (info->hash, l, false, false, false);
645 if (save)
646 *(char *) l = save;
647 }
648 }
649 return h;
650 }
651 #undef WRAP
652
653 /* Traverse a generic link hash table. Differs from bfd_hash_traverse
654 in the treatment of warning symbols. When warning symbols are
655 created they replace the real symbol, so you don't get to see the
656 real symbol in a bfd_hash_traverse. This traversal calls func with
657 the real symbol. */
658
659 void
bfd_link_hash_traverse(struct bfd_link_hash_table * htab,bool (* func)(struct bfd_link_hash_entry *,void *),void * info)660 bfd_link_hash_traverse
661 (struct bfd_link_hash_table *htab,
662 bool (*func) (struct bfd_link_hash_entry *, void *),
663 void *info)
664 {
665 unsigned int i;
666
667 htab->table.frozen = 1;
668 for (i = 0; i < htab->table.size; i++)
669 {
670 struct bfd_link_hash_entry *p;
671
672 p = (struct bfd_link_hash_entry *) htab->table.table[i];
673 for (; p != NULL; p = (struct bfd_link_hash_entry *) p->root.next)
674 if (!(*func) (p->type == bfd_link_hash_warning ? p->u.i.link : p, info))
675 goto out;
676 }
677 out:
678 htab->table.frozen = 0;
679 }
680
681 /* Add a symbol to the linker hash table undefs list. */
682
683 void
bfd_link_add_undef(struct bfd_link_hash_table * table,struct bfd_link_hash_entry * h)684 bfd_link_add_undef (struct bfd_link_hash_table *table,
685 struct bfd_link_hash_entry *h)
686 {
687 BFD_ASSERT (h->u.undef.next == NULL);
688 if (table->undefs_tail != NULL)
689 table->undefs_tail->u.undef.next = h;
690 if (table->undefs == NULL)
691 table->undefs = h;
692 table->undefs_tail = h;
693 }
694
695 /* The undefs list was designed so that in normal use we don't need to
696 remove entries. However, if symbols on the list are changed from
697 bfd_link_hash_undefined to either bfd_link_hash_undefweak or
698 bfd_link_hash_new for some reason, then they must be removed from the
699 list. Failure to do so might result in the linker attempting to add
700 the symbol to the list again at a later stage. */
701
702 void
bfd_link_repair_undef_list(struct bfd_link_hash_table * table)703 bfd_link_repair_undef_list (struct bfd_link_hash_table *table)
704 {
705 struct bfd_link_hash_entry **pun;
706
707 pun = &table->undefs;
708 while (*pun != NULL)
709 {
710 struct bfd_link_hash_entry *h = *pun;
711
712 if (h->type == bfd_link_hash_new
713 || h->type == bfd_link_hash_undefweak)
714 {
715 *pun = h->u.undef.next;
716 h->u.undef.next = NULL;
717 if (h == table->undefs_tail)
718 {
719 if (pun == &table->undefs)
720 table->undefs_tail = NULL;
721 else
722 /* pun points at an u.undef.next field. Go back to
723 the start of the link_hash_entry. */
724 table->undefs_tail = (struct bfd_link_hash_entry *)
725 ((char *) pun - ((char *) &h->u.undef.next - (char *) h));
726 break;
727 }
728 }
729 else
730 pun = &h->u.undef.next;
731 }
732 }
733
734 /* Routine to create an entry in a generic link hash table. */
735
736 struct bfd_hash_entry *
_bfd_generic_link_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)737 _bfd_generic_link_hash_newfunc (struct bfd_hash_entry *entry,
738 struct bfd_hash_table *table,
739 const char *string)
740 {
741 /* Allocate the structure if it has not already been allocated by a
742 subclass. */
743 if (entry == NULL)
744 {
745 entry = (struct bfd_hash_entry *)
746 bfd_hash_allocate (table, sizeof (struct generic_link_hash_entry));
747 if (entry == NULL)
748 return entry;
749 }
750
751 /* Call the allocation method of the superclass. */
752 entry = _bfd_link_hash_newfunc (entry, table, string);
753 if (entry)
754 {
755 struct generic_link_hash_entry *ret;
756
757 /* Set local fields. */
758 ret = (struct generic_link_hash_entry *) entry;
759 ret->written = false;
760 ret->sym = NULL;
761 }
762
763 return entry;
764 }
765
766 /* Create a generic link hash table. */
767
768 struct bfd_link_hash_table *
_bfd_generic_link_hash_table_create(bfd * abfd)769 _bfd_generic_link_hash_table_create (bfd *abfd)
770 {
771 struct generic_link_hash_table *ret;
772 size_t amt = sizeof (struct generic_link_hash_table);
773
774 ret = (struct generic_link_hash_table *) bfd_malloc (amt);
775 if (ret == NULL)
776 return NULL;
777 if (! _bfd_link_hash_table_init (&ret->root, abfd,
778 _bfd_generic_link_hash_newfunc,
779 sizeof (struct generic_link_hash_entry)))
780 {
781 free (ret);
782 return NULL;
783 }
784 return &ret->root;
785 }
786
787 void
_bfd_generic_link_hash_table_free(bfd * obfd)788 _bfd_generic_link_hash_table_free (bfd *obfd)
789 {
790 struct generic_link_hash_table *ret;
791
792 BFD_ASSERT (obfd->is_linker_output && obfd->link.hash);
793 ret = (struct generic_link_hash_table *) obfd->link.hash;
794 bfd_hash_table_free (&ret->root.table);
795 free (ret);
796 obfd->link.hash = NULL;
797 obfd->is_linker_output = false;
798 }
799
800 /* Grab the symbols for an object file when doing a generic link. We
801 store the symbols in the outsymbols field. We need to keep them
802 around for the entire link to ensure that we only read them once.
803 If we read them multiple times, we might wind up with relocs and
804 the hash table pointing to different instances of the symbol
805 structure. */
806
807 bool
bfd_generic_link_read_symbols(bfd * abfd)808 bfd_generic_link_read_symbols (bfd *abfd)
809 {
810 if (bfd_get_outsymbols (abfd) == NULL)
811 {
812 long symsize;
813 long symcount;
814
815 symsize = bfd_get_symtab_upper_bound (abfd);
816 if (symsize < 0)
817 return false;
818 abfd->outsymbols = bfd_alloc (abfd, symsize);
819 if (bfd_get_outsymbols (abfd) == NULL && symsize != 0)
820 return false;
821 symcount = bfd_canonicalize_symtab (abfd, bfd_get_outsymbols (abfd));
822 if (symcount < 0)
823 return false;
824 abfd->symcount = symcount;
825 }
826
827 return true;
828 }
829
830 /* Indicate that we are only retrieving symbol values from this
831 section. We want the symbols to act as though the values in the
832 file are absolute. */
833
834 void
_bfd_generic_link_just_syms(asection * sec,struct bfd_link_info * info ATTRIBUTE_UNUSED)835 _bfd_generic_link_just_syms (asection *sec,
836 struct bfd_link_info *info ATTRIBUTE_UNUSED)
837 {
838 sec->sec_info_type = SEC_INFO_TYPE_JUST_SYMS;
839 sec->output_section = bfd_abs_section_ptr;
840 sec->output_offset = sec->vma;
841 }
842
843 /* Copy the symbol type and other attributes for a linker script
844 assignment from HSRC to HDEST.
845 The default implementation does nothing. */
846 void
_bfd_generic_copy_link_hash_symbol_type(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_hash_entry * hdest ATTRIBUTE_UNUSED,struct bfd_link_hash_entry * hsrc ATTRIBUTE_UNUSED)847 _bfd_generic_copy_link_hash_symbol_type (bfd *abfd ATTRIBUTE_UNUSED,
848 struct bfd_link_hash_entry *hdest ATTRIBUTE_UNUSED,
849 struct bfd_link_hash_entry *hsrc ATTRIBUTE_UNUSED)
850 {
851 }
852
853 /* Generic function to add symbols from an object file to the
854 global hash table. */
855
856 bool
_bfd_generic_link_add_symbols(bfd * abfd,struct bfd_link_info * info)857 _bfd_generic_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
858 {
859 bool ret;
860
861 switch (bfd_get_format (abfd))
862 {
863 case bfd_object:
864 ret = generic_link_add_object_symbols (abfd, info);
865 break;
866 case bfd_archive:
867 ret = (_bfd_generic_link_add_archive_symbols
868 (abfd, info, generic_link_check_archive_element));
869 break;
870 default:
871 bfd_set_error (bfd_error_wrong_format);
872 ret = false;
873 }
874
875 return ret;
876 }
877
878 /* Add symbols from an object file to the global hash table. */
879
880 static bool
generic_link_add_object_symbols(bfd * abfd,struct bfd_link_info * info)881 generic_link_add_object_symbols (bfd *abfd,
882 struct bfd_link_info *info)
883 {
884 bfd_size_type symcount;
885 struct bfd_symbol **outsyms;
886
887 if (!bfd_generic_link_read_symbols (abfd))
888 return false;
889 symcount = _bfd_generic_link_get_symcount (abfd);
890 outsyms = _bfd_generic_link_get_symbols (abfd);
891 return generic_link_add_symbol_list (abfd, info, symcount, outsyms);
892 }
893
894 /* Generic function to add symbols from an archive file to the global
895 hash file. This function presumes that the archive symbol table
896 has already been read in (this is normally done by the
897 bfd_check_format entry point). It looks through the archive symbol
898 table for symbols that are undefined or common in the linker global
899 symbol hash table. When one is found, the CHECKFN argument is used
900 to see if an object file should be included. This allows targets
901 to customize common symbol behaviour. CHECKFN should set *PNEEDED
902 to TRUE if the object file should be included, and must also call
903 the bfd_link_info add_archive_element callback function and handle
904 adding the symbols to the global hash table. CHECKFN must notice
905 if the callback indicates a substitute BFD, and arrange to add
906 those symbols instead if it does so. CHECKFN should only return
907 FALSE if some sort of error occurs. */
908
909 bool
_bfd_generic_link_add_archive_symbols(bfd * abfd,struct bfd_link_info * info,bool (* checkfn)(bfd *,struct bfd_link_info *,struct bfd_link_hash_entry *,const char *,bool *))910 _bfd_generic_link_add_archive_symbols
911 (bfd *abfd,
912 struct bfd_link_info *info,
913 bool (*checkfn) (bfd *, struct bfd_link_info *,
914 struct bfd_link_hash_entry *, const char *, bool *))
915 {
916 bool loop;
917 bfd_size_type amt;
918 unsigned char *included;
919
920 if (! bfd_has_map (abfd))
921 {
922 /* An empty archive is a special case. */
923 if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
924 return true;
925 bfd_set_error (bfd_error_no_armap);
926 return false;
927 }
928
929 amt = bfd_ardata (abfd)->symdef_count;
930 if (amt == 0)
931 return true;
932 amt *= sizeof (*included);
933 included = (unsigned char *) bfd_zmalloc (amt);
934 if (included == NULL)
935 return false;
936
937 do
938 {
939 carsym *arsyms;
940 carsym *arsym_end;
941 carsym *arsym;
942 unsigned int indx;
943 file_ptr last_ar_offset = -1;
944 bool needed = false;
945 bfd *element = NULL;
946
947 loop = false;
948 arsyms = bfd_ardata (abfd)->symdefs;
949 arsym_end = arsyms + bfd_ardata (abfd)->symdef_count;
950 for (arsym = arsyms, indx = 0; arsym < arsym_end; arsym++, indx++)
951 {
952 struct bfd_link_hash_entry *h;
953 struct bfd_link_hash_entry *undefs_tail;
954
955 if (included[indx])
956 continue;
957 if (needed && arsym->file_offset == last_ar_offset)
958 {
959 included[indx] = 1;
960 continue;
961 }
962
963 if (arsym->name == NULL)
964 goto error_return;
965
966 h = bfd_link_hash_lookup (info->hash, arsym->name,
967 false, false, true);
968
969 if (h == NULL
970 && info->pei386_auto_import
971 && startswith (arsym->name, "__imp_"))
972 h = bfd_link_hash_lookup (info->hash, arsym->name + 6,
973 false, false, true);
974 if (h == NULL)
975 continue;
976
977 if (h->type != bfd_link_hash_undefined
978 && h->type != bfd_link_hash_common)
979 {
980 if (h->type != bfd_link_hash_undefweak)
981 /* Symbol must be defined. Don't check it again. */
982 included[indx] = 1;
983 continue;
984 }
985
986 if (last_ar_offset != arsym->file_offset)
987 {
988 last_ar_offset = arsym->file_offset;
989 element = _bfd_get_elt_at_filepos (abfd, last_ar_offset,
990 info);
991 if (element == NULL
992 || !bfd_check_format (element, bfd_object))
993 goto error_return;
994 }
995
996 undefs_tail = info->hash->undefs_tail;
997
998 /* CHECKFN will see if this element should be included, and
999 go ahead and include it if appropriate. */
1000 if (! (*checkfn) (element, info, h, arsym->name, &needed))
1001 goto error_return;
1002
1003 if (needed)
1004 {
1005 unsigned int mark;
1006
1007 /* Look backward to mark all symbols from this object file
1008 which we have already seen in this pass. */
1009 mark = indx;
1010 do
1011 {
1012 included[mark] = 1;
1013 if (mark == 0)
1014 break;
1015 --mark;
1016 }
1017 while (arsyms[mark].file_offset == last_ar_offset);
1018
1019 if (undefs_tail != info->hash->undefs_tail)
1020 loop = true;
1021 }
1022 }
1023 } while (loop);
1024
1025 free (included);
1026 return true;
1027
1028 error_return:
1029 free (included);
1030 return false;
1031 }
1032
1033 /* See if we should include an archive element. */
1034
1035 static bool
generic_link_check_archive_element(bfd * abfd,struct bfd_link_info * info,struct bfd_link_hash_entry * h,const char * name ATTRIBUTE_UNUSED,bool * pneeded)1036 generic_link_check_archive_element (bfd *abfd,
1037 struct bfd_link_info *info,
1038 struct bfd_link_hash_entry *h,
1039 const char *name ATTRIBUTE_UNUSED,
1040 bool *pneeded)
1041 {
1042 asymbol **pp, **ppend;
1043
1044 *pneeded = false;
1045
1046 if (!bfd_generic_link_read_symbols (abfd))
1047 return false;
1048
1049 pp = _bfd_generic_link_get_symbols (abfd);
1050 ppend = pp + _bfd_generic_link_get_symcount (abfd);
1051 for (; pp < ppend; pp++)
1052 {
1053 asymbol *p;
1054
1055 p = *pp;
1056
1057 /* We are only interested in globally visible symbols. */
1058 if (! bfd_is_com_section (p->section)
1059 && (p->flags & (BSF_GLOBAL | BSF_INDIRECT | BSF_WEAK)) == 0)
1060 continue;
1061
1062 /* We are only interested if we know something about this
1063 symbol, and it is undefined or common. An undefined weak
1064 symbol (type bfd_link_hash_undefweak) is not considered to be
1065 a reference when pulling files out of an archive. See the
1066 SVR4 ABI, p. 4-27. */
1067 h = bfd_link_hash_lookup (info->hash, bfd_asymbol_name (p), false,
1068 false, true);
1069 if (h == NULL
1070 || (h->type != bfd_link_hash_undefined
1071 && h->type != bfd_link_hash_common))
1072 continue;
1073
1074 /* P is a symbol we are looking for. */
1075
1076 if (! bfd_is_com_section (p->section)
1077 || (h->type == bfd_link_hash_undefined
1078 && h->u.undef.abfd == NULL))
1079 {
1080 /* P is not a common symbol, or an undefined reference was
1081 created from outside BFD such as from a linker -u option.
1082 This object file defines the symbol, so pull it in. */
1083 *pneeded = true;
1084 if (!(*info->callbacks
1085 ->add_archive_element) (info, abfd, bfd_asymbol_name (p),
1086 &abfd))
1087 return false;
1088 /* Potentially, the add_archive_element hook may have set a
1089 substitute BFD for us. */
1090 return bfd_link_add_symbols (abfd, info);
1091 }
1092
1093 /* P is a common symbol. */
1094
1095 if (h->type == bfd_link_hash_undefined)
1096 {
1097 bfd *symbfd;
1098 bfd_vma size;
1099 unsigned int power;
1100
1101 /* Turn the symbol into a common symbol but do not link in
1102 the object file. This is how a.out works. Object
1103 formats that require different semantics must implement
1104 this function differently. This symbol is already on the
1105 undefs list. We add the section to a common section
1106 attached to symbfd to ensure that it is in a BFD which
1107 will be linked in. */
1108 symbfd = h->u.undef.abfd;
1109 h->type = bfd_link_hash_common;
1110 h->u.c.p = (struct bfd_link_hash_common_entry *)
1111 bfd_hash_allocate (&info->hash->table,
1112 sizeof (struct bfd_link_hash_common_entry));
1113 if (h->u.c.p == NULL)
1114 return false;
1115
1116 size = bfd_asymbol_value (p);
1117 h->u.c.size = size;
1118
1119 power = bfd_log2 (size);
1120 if (power > 4)
1121 power = 4;
1122 h->u.c.p->alignment_power = power;
1123
1124 if (p->section == bfd_com_section_ptr)
1125 h->u.c.p->section = bfd_make_section_old_way (symbfd, "COMMON");
1126 else
1127 h->u.c.p->section = bfd_make_section_old_way (symbfd,
1128 p->section->name);
1129 h->u.c.p->section->flags |= SEC_ALLOC;
1130 }
1131 else
1132 {
1133 /* Adjust the size of the common symbol if necessary. This
1134 is how a.out works. Object formats that require
1135 different semantics must implement this function
1136 differently. */
1137 if (bfd_asymbol_value (p) > h->u.c.size)
1138 h->u.c.size = bfd_asymbol_value (p);
1139 }
1140 }
1141
1142 /* This archive element is not needed. */
1143 return true;
1144 }
1145
1146 /* Add the symbols from an object file to the global hash table. ABFD
1147 is the object file. INFO is the linker information. SYMBOL_COUNT
1148 is the number of symbols. SYMBOLS is the list of symbols. */
1149
1150 static bool
generic_link_add_symbol_list(bfd * abfd,struct bfd_link_info * info,bfd_size_type symbol_count,asymbol ** symbols)1151 generic_link_add_symbol_list (bfd *abfd,
1152 struct bfd_link_info *info,
1153 bfd_size_type symbol_count,
1154 asymbol **symbols)
1155 {
1156 asymbol **pp, **ppend;
1157
1158 pp = symbols;
1159 ppend = symbols + symbol_count;
1160 for (; pp < ppend; pp++)
1161 {
1162 asymbol *p;
1163
1164 p = *pp;
1165
1166 if ((p->flags & (BSF_INDIRECT
1167 | BSF_WARNING
1168 | BSF_GLOBAL
1169 | BSF_CONSTRUCTOR
1170 | BSF_WEAK)) != 0
1171 || bfd_is_und_section (bfd_asymbol_section (p))
1172 || bfd_is_com_section (bfd_asymbol_section (p))
1173 || bfd_is_ind_section (bfd_asymbol_section (p)))
1174 {
1175 const char *name;
1176 const char *string;
1177 struct generic_link_hash_entry *h;
1178 struct bfd_link_hash_entry *bh;
1179
1180 string = name = bfd_asymbol_name (p);
1181 if (((p->flags & BSF_INDIRECT) != 0
1182 || bfd_is_ind_section (p->section))
1183 && pp + 1 < ppend)
1184 {
1185 pp++;
1186 string = bfd_asymbol_name (*pp);
1187 }
1188 else if ((p->flags & BSF_WARNING) != 0
1189 && pp + 1 < ppend)
1190 {
1191 /* The name of P is actually the warning string, and the
1192 next symbol is the one to warn about. */
1193 pp++;
1194 name = bfd_asymbol_name (*pp);
1195 }
1196
1197 bh = NULL;
1198 if (! (_bfd_generic_link_add_one_symbol
1199 (info, abfd, name, p->flags, bfd_asymbol_section (p),
1200 p->value, string, false, false, &bh)))
1201 return false;
1202 h = (struct generic_link_hash_entry *) bh;
1203
1204 /* If this is a constructor symbol, and the linker didn't do
1205 anything with it, then we want to just pass the symbol
1206 through to the output file. This will happen when
1207 linking with -r. */
1208 if ((p->flags & BSF_CONSTRUCTOR) != 0
1209 && (h == NULL || h->root.type == bfd_link_hash_new))
1210 {
1211 p->udata.p = NULL;
1212 continue;
1213 }
1214
1215 /* Save the BFD symbol so that we don't lose any backend
1216 specific information that may be attached to it. We only
1217 want this one if it gives more information than the
1218 existing one; we don't want to replace a defined symbol
1219 with an undefined one. This routine may be called with a
1220 hash table other than the generic hash table, so we only
1221 do this if we are certain that the hash table is a
1222 generic one. */
1223 if (info->output_bfd->xvec == abfd->xvec)
1224 {
1225 if (h->sym == NULL
1226 || (! bfd_is_und_section (bfd_asymbol_section (p))
1227 && (! bfd_is_com_section (bfd_asymbol_section (p))
1228 || bfd_is_und_section (bfd_asymbol_section (h->sym)))))
1229 {
1230 h->sym = p;
1231 /* BSF_OLD_COMMON is a hack to support COFF reloc
1232 reading, and it should go away when the COFF
1233 linker is switched to the new version. */
1234 if (bfd_is_com_section (bfd_asymbol_section (p)))
1235 p->flags |= BSF_OLD_COMMON;
1236 }
1237 }
1238
1239 /* Store a back pointer from the symbol to the hash
1240 table entry for the benefit of relaxation code until
1241 it gets rewritten to not use asymbol structures.
1242 Setting this is also used to check whether these
1243 symbols were set up by the generic linker. */
1244 p->udata.p = h;
1245 }
1246 }
1247
1248 return true;
1249 }
1250
1251 /* We use a state table to deal with adding symbols from an object
1252 file. The first index into the state table describes the symbol
1253 from the object file. The second index into the state table is the
1254 type of the symbol in the hash table. */
1255
1256 /* The symbol from the object file is turned into one of these row
1257 values. */
1258
1259 enum link_row
1260 {
1261 UNDEF_ROW, /* Undefined. */
1262 UNDEFW_ROW, /* Weak undefined. */
1263 DEF_ROW, /* Defined. */
1264 DEFW_ROW, /* Weak defined. */
1265 COMMON_ROW, /* Common. */
1266 INDR_ROW, /* Indirect. */
1267 WARN_ROW, /* Warning. */
1268 SET_ROW /* Member of set. */
1269 };
1270
1271 /* apparently needed for Hitachi 3050R(HI-UX/WE2)? */
1272 #undef FAIL
1273
1274 /* The actions to take in the state table. */
1275
1276 enum link_action
1277 {
1278 FAIL, /* Abort. */
1279 UND, /* Mark symbol undefined. */
1280 WEAK, /* Mark symbol weak undefined. */
1281 DEF, /* Mark symbol defined. */
1282 DEFW, /* Mark symbol weak defined. */
1283 COM, /* Mark symbol common. */
1284 REF, /* Mark defined symbol referenced. */
1285 CREF, /* Possibly warn about common reference to defined symbol. */
1286 CDEF, /* Define existing common symbol. */
1287 NOACT, /* No action. */
1288 BIG, /* Mark symbol common using largest size. */
1289 MDEF, /* Multiple definition error. */
1290 MIND, /* Multiple indirect symbols. */
1291 IND, /* Make indirect symbol. */
1292 CIND, /* Make indirect symbol from existing common symbol. */
1293 SET, /* Add value to set. */
1294 MWARN, /* Make warning symbol. */
1295 WARN, /* Warn if referenced, else MWARN. */
1296 CYCLE, /* Repeat with symbol pointed to. */
1297 REFC, /* Mark indirect symbol referenced and then CYCLE. */
1298 WARNC /* Issue warning and then CYCLE. */
1299 };
1300
1301 /* The state table itself. The first index is a link_row and the
1302 second index is a bfd_link_hash_type. */
1303
1304 static const enum link_action link_action[8][8] =
1305 {
1306 /* current\prev new undef undefw def defw com indr warn */
1307 /* UNDEF_ROW */ {UND, NOACT, UND, REF, REF, NOACT, REFC, WARNC },
1308 /* UNDEFW_ROW */ {WEAK, NOACT, NOACT, REF, REF, NOACT, REFC, WARNC },
1309 /* DEF_ROW */ {DEF, DEF, DEF, MDEF, DEF, CDEF, MIND, CYCLE },
1310 /* DEFW_ROW */ {DEFW, DEFW, DEFW, NOACT, NOACT, NOACT, NOACT, CYCLE },
1311 /* COMMON_ROW */ {COM, COM, COM, CREF, COM, BIG, REFC, WARNC },
1312 /* INDR_ROW */ {IND, IND, IND, MDEF, IND, CIND, MIND, CYCLE },
1313 /* WARN_ROW */ {MWARN, WARN, WARN, WARN, WARN, WARN, WARN, NOACT },
1314 /* SET_ROW */ {SET, SET, SET, SET, SET, SET, CYCLE, CYCLE }
1315 };
1316
1317 /* Most of the entries in the LINK_ACTION table are straightforward,
1318 but a few are somewhat subtle.
1319
1320 A reference to an indirect symbol (UNDEF_ROW/indr or
1321 UNDEFW_ROW/indr) is counted as a reference both to the indirect
1322 symbol and to the symbol the indirect symbol points to.
1323
1324 A reference to a warning symbol (UNDEF_ROW/warn or UNDEFW_ROW/warn)
1325 causes the warning to be issued.
1326
1327 A common definition of an indirect symbol (COMMON_ROW/indr) is
1328 treated as a multiple definition error. Likewise for an indirect
1329 definition of a common symbol (INDR_ROW/com).
1330
1331 An indirect definition of a warning (INDR_ROW/warn) does not cause
1332 the warning to be issued.
1333
1334 If a warning is created for an indirect symbol (WARN_ROW/indr) no
1335 warning is created for the symbol the indirect symbol points to.
1336
1337 Adding an entry to a set does not count as a reference to a set,
1338 and no warning is issued (SET_ROW/warn). */
1339
1340 /* Return the BFD in which a hash entry has been defined, if known. */
1341
1342 static bfd *
hash_entry_bfd(struct bfd_link_hash_entry * h)1343 hash_entry_bfd (struct bfd_link_hash_entry *h)
1344 {
1345 while (h->type == bfd_link_hash_warning)
1346 h = h->u.i.link;
1347 switch (h->type)
1348 {
1349 default:
1350 return NULL;
1351 case bfd_link_hash_undefined:
1352 case bfd_link_hash_undefweak:
1353 return h->u.undef.abfd;
1354 case bfd_link_hash_defined:
1355 case bfd_link_hash_defweak:
1356 return h->u.def.section->owner;
1357 case bfd_link_hash_common:
1358 return h->u.c.p->section->owner;
1359 }
1360 /*NOTREACHED*/
1361 }
1362
1363 /* Add a symbol to the global hash table.
1364 ABFD is the BFD the symbol comes from.
1365 NAME is the name of the symbol.
1366 FLAGS is the BSF_* bits associated with the symbol.
1367 SECTION is the section in which the symbol is defined; this may be
1368 bfd_und_section_ptr or bfd_com_section_ptr.
1369 VALUE is the value of the symbol, relative to the section.
1370 STRING is used for either an indirect symbol, in which case it is
1371 the name of the symbol to indirect to, or a warning symbol, in
1372 which case it is the warning string.
1373 COPY is TRUE if NAME or STRING must be copied into locally
1374 allocated memory if they need to be saved.
1375 COLLECT is TRUE if we should automatically collect gcc constructor
1376 or destructor names as collect2 does.
1377 HASHP, if not NULL, is a place to store the created hash table
1378 entry; if *HASHP is not NULL, the caller has already looked up
1379 the hash table entry, and stored it in *HASHP. */
1380
1381 bool
_bfd_generic_link_add_one_symbol(struct bfd_link_info * info,bfd * abfd,const char * name,flagword flags,asection * section,bfd_vma value,const char * string,bool copy,bool collect,struct bfd_link_hash_entry ** hashp)1382 _bfd_generic_link_add_one_symbol (struct bfd_link_info *info,
1383 bfd *abfd,
1384 const char *name,
1385 flagword flags,
1386 asection *section,
1387 bfd_vma value,
1388 const char *string,
1389 bool copy,
1390 bool collect,
1391 struct bfd_link_hash_entry **hashp)
1392 {
1393 enum link_row row;
1394 struct bfd_link_hash_entry *h;
1395 struct bfd_link_hash_entry *inh = NULL;
1396 bool cycle;
1397
1398 BFD_ASSERT (section != NULL);
1399
1400 if (bfd_is_ind_section (section)
1401 || (flags & BSF_INDIRECT) != 0)
1402 {
1403 row = INDR_ROW;
1404 /* Create the indirect symbol here. This is for the benefit of
1405 the plugin "notice" function.
1406 STRING is the name of the symbol we want to indirect to. */
1407 inh = bfd_wrapped_link_hash_lookup (abfd, info, string, true,
1408 copy, false);
1409 if (inh == NULL)
1410 return false;
1411 }
1412 else if ((flags & BSF_WARNING) != 0)
1413 row = WARN_ROW;
1414 else if ((flags & BSF_CONSTRUCTOR) != 0)
1415 row = SET_ROW;
1416 else if (bfd_is_und_section (section))
1417 {
1418 if ((flags & BSF_WEAK) != 0)
1419 row = UNDEFW_ROW;
1420 else
1421 row = UNDEF_ROW;
1422 }
1423 else if ((flags & BSF_WEAK) != 0)
1424 row = DEFW_ROW;
1425 else if (bfd_is_com_section (section))
1426 {
1427 row = COMMON_ROW;
1428 if (!bfd_link_relocatable (info)
1429 && name != NULL
1430 && name[0] == '_'
1431 && name[1] == '_'
1432 && strcmp (name + (name[2] == '_'), "__gnu_lto_slim") == 0)
1433 _bfd_error_handler
1434 (_("%pB: plugin needed to handle lto object"), abfd);
1435 }
1436 else
1437 row = DEF_ROW;
1438
1439 if (hashp != NULL && *hashp != NULL)
1440 h = *hashp;
1441 else
1442 {
1443 if (row == UNDEF_ROW || row == UNDEFW_ROW)
1444 h = bfd_wrapped_link_hash_lookup (abfd, info, name, true, copy, false);
1445 else
1446 h = bfd_link_hash_lookup (info->hash, name, true, copy, false);
1447 if (h == NULL)
1448 {
1449 if (hashp != NULL)
1450 *hashp = NULL;
1451 return false;
1452 }
1453 }
1454
1455 if (info->notice_all
1456 || (info->notice_hash != NULL
1457 && bfd_hash_lookup (info->notice_hash, name, false, false) != NULL))
1458 {
1459 if (! (*info->callbacks->notice) (info, h, inh,
1460 abfd, section, value, flags))
1461 return false;
1462 }
1463
1464 if (hashp != NULL)
1465 *hashp = h;
1466
1467 do
1468 {
1469 enum link_action action;
1470 int prev;
1471
1472 prev = h->type;
1473 /* Treat symbols defined by early linker script pass as undefined. */
1474 if (h->ldscript_def)
1475 prev = bfd_link_hash_undefined;
1476 cycle = false;
1477 action = link_action[(int) row][prev];
1478 switch (action)
1479 {
1480 case FAIL:
1481 abort ();
1482
1483 case NOACT:
1484 /* Do nothing. */
1485 break;
1486
1487 case UND:
1488 /* Make a new undefined symbol. */
1489 h->type = bfd_link_hash_undefined;
1490 h->u.undef.abfd = abfd;
1491 bfd_link_add_undef (info->hash, h);
1492 break;
1493
1494 case WEAK:
1495 /* Make a new weak undefined symbol. */
1496 h->type = bfd_link_hash_undefweak;
1497 h->u.undef.abfd = abfd;
1498 break;
1499
1500 case CDEF:
1501 /* We have found a definition for a symbol which was
1502 previously common. */
1503 BFD_ASSERT (h->type == bfd_link_hash_common);
1504 (*info->callbacks->multiple_common) (info, h, abfd,
1505 bfd_link_hash_defined, 0);
1506 /* Fall through. */
1507 case DEF:
1508 case DEFW:
1509 {
1510 enum bfd_link_hash_type oldtype;
1511
1512 /* Define a symbol. */
1513 oldtype = h->type;
1514 if (action == DEFW)
1515 h->type = bfd_link_hash_defweak;
1516 else
1517 h->type = bfd_link_hash_defined;
1518 h->u.def.section = section;
1519 h->u.def.value = value;
1520 h->linker_def = 0;
1521 h->ldscript_def = 0;
1522
1523 /* If we have been asked to, we act like collect2 and
1524 identify all functions that might be global
1525 constructors and destructors and pass them up in a
1526 callback. We only do this for certain object file
1527 types, since many object file types can handle this
1528 automatically. */
1529 if (collect && name[0] == '_')
1530 {
1531 const char *s;
1532
1533 /* A constructor or destructor name starts like this:
1534 _+GLOBAL_[_.$][ID][_.$] where the first [_.$] and
1535 the second are the same character (we accept any
1536 character there, in case a new object file format
1537 comes along with even worse naming restrictions). */
1538
1539 #define CONS_PREFIX "GLOBAL_"
1540 #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1)
1541
1542 s = name + 1;
1543 while (*s == '_')
1544 ++s;
1545 if (s[0] == 'G' && startswith (s, CONS_PREFIX))
1546 {
1547 char c;
1548
1549 c = s[CONS_PREFIX_LEN + 1];
1550 if ((c == 'I' || c == 'D')
1551 && s[CONS_PREFIX_LEN] == s[CONS_PREFIX_LEN + 2])
1552 {
1553 /* If this is a definition of a symbol which
1554 was previously weakly defined, we are in
1555 trouble. We have already added a
1556 constructor entry for the weak defined
1557 symbol, and now we are trying to add one
1558 for the new symbol. Fortunately, this case
1559 should never arise in practice. */
1560 if (oldtype == bfd_link_hash_defweak)
1561 abort ();
1562
1563 (*info->callbacks->constructor) (info, c == 'I',
1564 h->root.string, abfd,
1565 section, value);
1566 }
1567 }
1568 }
1569 }
1570
1571 break;
1572
1573 case COM:
1574 /* We have found a common definition for a symbol. */
1575 if (h->type == bfd_link_hash_new)
1576 bfd_link_add_undef (info->hash, h);
1577 h->type = bfd_link_hash_common;
1578 h->u.c.p = (struct bfd_link_hash_common_entry *)
1579 bfd_hash_allocate (&info->hash->table,
1580 sizeof (struct bfd_link_hash_common_entry));
1581 if (h->u.c.p == NULL)
1582 return false;
1583
1584 h->u.c.size = value;
1585
1586 /* Select a default alignment based on the size. This may
1587 be overridden by the caller. */
1588 {
1589 unsigned int power;
1590
1591 power = bfd_log2 (value);
1592 if (power > 4)
1593 power = 4;
1594 h->u.c.p->alignment_power = power;
1595 }
1596
1597 /* The section of a common symbol is only used if the common
1598 symbol is actually allocated. It basically provides a
1599 hook for the linker script to decide which output section
1600 the common symbols should be put in. In most cases, the
1601 section of a common symbol will be bfd_com_section_ptr,
1602 the code here will choose a common symbol section named
1603 "COMMON", and the linker script will contain *(COMMON) in
1604 the appropriate place. A few targets use separate common
1605 sections for small symbols, and they require special
1606 handling. */
1607 if (section == bfd_com_section_ptr)
1608 {
1609 h->u.c.p->section = bfd_make_section_old_way (abfd, "COMMON");
1610 h->u.c.p->section->flags |= SEC_ALLOC;
1611 }
1612 else if (section->owner != abfd)
1613 {
1614 h->u.c.p->section = bfd_make_section_old_way (abfd,
1615 section->name);
1616 h->u.c.p->section->flags |= SEC_ALLOC;
1617 }
1618 else
1619 h->u.c.p->section = section;
1620 h->linker_def = 0;
1621 h->ldscript_def = 0;
1622 break;
1623
1624 case REF:
1625 /* A reference to a defined symbol. */
1626 if (h->u.undef.next == NULL && info->hash->undefs_tail != h)
1627 h->u.undef.next = h;
1628 break;
1629
1630 case BIG:
1631 /* We have found a common definition for a symbol which
1632 already had a common definition. Use the maximum of the
1633 two sizes, and use the section required by the larger symbol. */
1634 BFD_ASSERT (h->type == bfd_link_hash_common);
1635 (*info->callbacks->multiple_common) (info, h, abfd,
1636 bfd_link_hash_common, value);
1637 if (value > h->u.c.size)
1638 {
1639 unsigned int power;
1640
1641 h->u.c.size = value;
1642
1643 /* Select a default alignment based on the size. This may
1644 be overridden by the caller. */
1645 power = bfd_log2 (value);
1646 if (power > 4)
1647 power = 4;
1648 h->u.c.p->alignment_power = power;
1649
1650 /* Some systems have special treatment for small commons,
1651 hence we want to select the section used by the larger
1652 symbol. This makes sure the symbol does not go in a
1653 small common section if it is now too large. */
1654 if (section == bfd_com_section_ptr)
1655 {
1656 h->u.c.p->section
1657 = bfd_make_section_old_way (abfd, "COMMON");
1658 h->u.c.p->section->flags |= SEC_ALLOC;
1659 }
1660 else if (section->owner != abfd)
1661 {
1662 h->u.c.p->section
1663 = bfd_make_section_old_way (abfd, section->name);
1664 h->u.c.p->section->flags |= SEC_ALLOC;
1665 }
1666 else
1667 h->u.c.p->section = section;
1668 }
1669 break;
1670
1671 case CREF:
1672 /* We have found a common definition for a symbol which
1673 was already defined. */
1674 (*info->callbacks->multiple_common) (info, h, abfd,
1675 bfd_link_hash_common, value);
1676 break;
1677
1678 case MIND:
1679 /* Multiple indirect symbols. This is OK if they both point
1680 to the same symbol. */
1681 if (h->u.i.link->type == bfd_link_hash_defweak)
1682 {
1683 /* It is also OK to redefine a symbol that indirects to
1684 a weak definition. So for sym@ver -> sym@@ver where
1685 sym@@ver is weak and we have a new strong sym@ver,
1686 redefine sym@@ver. Of course if there exists
1687 sym -> sym@@ver then this also redefines sym. */
1688 h = h->u.i.link;
1689 cycle = true;
1690 break;
1691 }
1692 if (string != NULL && strcmp (h->u.i.link->root.string, string) == 0)
1693 break;
1694 /* Fall through. */
1695 case MDEF:
1696 /* Handle a multiple definition. */
1697 (*info->callbacks->multiple_definition) (info, h,
1698 abfd, section, value);
1699 break;
1700
1701 case CIND:
1702 /* Create an indirect symbol from an existing common symbol. */
1703 BFD_ASSERT (h->type == bfd_link_hash_common);
1704 (*info->callbacks->multiple_common) (info, h, abfd,
1705 bfd_link_hash_indirect, 0);
1706 /* Fall through. */
1707 case IND:
1708 if (inh->type == bfd_link_hash_indirect
1709 && inh->u.i.link == h)
1710 {
1711 _bfd_error_handler
1712 /* xgettext:c-format */
1713 (_("%pB: indirect symbol `%s' to `%s' is a loop"),
1714 abfd, name, string);
1715 bfd_set_error (bfd_error_invalid_operation);
1716 return false;
1717 }
1718 if (inh->type == bfd_link_hash_new)
1719 {
1720 inh->type = bfd_link_hash_undefined;
1721 inh->u.undef.abfd = abfd;
1722 bfd_link_add_undef (info->hash, inh);
1723 }
1724
1725 /* If the indirect symbol has been referenced, we need to
1726 push the reference down to the symbol we are referencing. */
1727 if (h->type != bfd_link_hash_new)
1728 {
1729 /* ??? If inh->type == bfd_link_hash_undefweak this
1730 converts inh to bfd_link_hash_undefined. */
1731 row = UNDEF_ROW;
1732 cycle = true;
1733 }
1734
1735 h->type = bfd_link_hash_indirect;
1736 h->u.i.link = inh;
1737 /* Not setting h = h->u.i.link here means that when cycle is
1738 set above we'll always go to REFC, and then cycle again
1739 to the indirected symbol. This means that any successful
1740 change of an existing symbol to indirect counts as a
1741 reference. ??? That may not be correct when the existing
1742 symbol was defweak. */
1743 break;
1744
1745 case SET:
1746 /* Add an entry to a set. */
1747 (*info->callbacks->add_to_set) (info, h, BFD_RELOC_CTOR,
1748 abfd, section, value);
1749 break;
1750
1751 case WARNC:
1752 /* Issue a warning and cycle, except when the reference is
1753 in LTO IR. */
1754 if (h->u.i.warning != NULL
1755 && (abfd->flags & BFD_PLUGIN) == 0)
1756 {
1757 (*info->callbacks->warning) (info, h->u.i.warning,
1758 h->root.string, abfd, NULL, 0);
1759 /* Only issue a warning once. */
1760 h->u.i.warning = NULL;
1761 }
1762 /* Fall through. */
1763 case CYCLE:
1764 /* Try again with the referenced symbol. */
1765 h = h->u.i.link;
1766 cycle = true;
1767 break;
1768
1769 case REFC:
1770 /* A reference to an indirect symbol. */
1771 if (h->u.undef.next == NULL && info->hash->undefs_tail != h)
1772 h->u.undef.next = h;
1773 h = h->u.i.link;
1774 cycle = true;
1775 break;
1776
1777 case WARN:
1778 /* Warn if this symbol has been referenced already from non-IR,
1779 otherwise add a warning. */
1780 if ((!info->lto_plugin_active
1781 && (h->u.undef.next != NULL || info->hash->undefs_tail == h))
1782 || h->non_ir_ref_regular
1783 || h->non_ir_ref_dynamic)
1784 {
1785 (*info->callbacks->warning) (info, string, h->root.string,
1786 hash_entry_bfd (h), NULL, 0);
1787 /* PR 31067: If garbage collection is enabled then the
1788 referenced symbol may actually be discarded later on.
1789 This could be very confusing to the user. So give them
1790 a hint as to what might be happening. */
1791 if (info->gc_sections)
1792 (*info->callbacks->info)
1793 (_("%P: %pB: note: the message above does not take linker garbage collection into account\n"),
1794 hash_entry_bfd (h));
1795 break;
1796 }
1797 /* Fall through. */
1798 case MWARN:
1799 /* Make a warning symbol. */
1800 {
1801 struct bfd_link_hash_entry *sub;
1802
1803 /* STRING is the warning to give. */
1804 sub = ((struct bfd_link_hash_entry *)
1805 ((*info->hash->table.newfunc)
1806 (NULL, &info->hash->table, h->root.string)));
1807 if (sub == NULL)
1808 return false;
1809 *sub = *h;
1810 sub->type = bfd_link_hash_warning;
1811 sub->u.i.link = h;
1812 if (! copy)
1813 sub->u.i.warning = string;
1814 else
1815 {
1816 char *w;
1817 size_t len = strlen (string) + 1;
1818
1819 w = (char *) bfd_hash_allocate (&info->hash->table, len);
1820 if (w == NULL)
1821 return false;
1822 memcpy (w, string, len);
1823 sub->u.i.warning = w;
1824 }
1825
1826 bfd_hash_replace (&info->hash->table,
1827 (struct bfd_hash_entry *) h,
1828 (struct bfd_hash_entry *) sub);
1829 if (hashp != NULL)
1830 *hashp = sub;
1831 }
1832 break;
1833 }
1834 }
1835 while (cycle);
1836
1837 return true;
1838 }
1839
1840 /* Generic final link routine. */
1841
1842 bool
_bfd_generic_final_link(bfd * abfd,struct bfd_link_info * info)1843 _bfd_generic_final_link (bfd *abfd, struct bfd_link_info *info)
1844 {
1845 bfd *sub;
1846 asection *o;
1847 struct bfd_link_order *p;
1848 size_t outsymalloc;
1849 struct generic_write_global_symbol_info wginfo;
1850
1851 abfd->outsymbols = NULL;
1852 abfd->symcount = 0;
1853 outsymalloc = 0;
1854
1855 /* Mark all sections which will be included in the output file. */
1856 for (o = abfd->sections; o != NULL; o = o->next)
1857 for (p = o->map_head.link_order; p != NULL; p = p->next)
1858 if (p->type == bfd_indirect_link_order)
1859 p->u.indirect.section->linker_mark = true;
1860
1861 /* Build the output symbol table. */
1862 for (sub = info->input_bfds; sub != NULL; sub = sub->link.next)
1863 if (! _bfd_generic_link_output_symbols (abfd, sub, info, &outsymalloc))
1864 return false;
1865
1866 /* Accumulate the global symbols. */
1867 wginfo.info = info;
1868 wginfo.output_bfd = abfd;
1869 wginfo.psymalloc = &outsymalloc;
1870 _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info),
1871 _bfd_generic_link_write_global_symbol,
1872 &wginfo);
1873
1874 /* Make sure we have a trailing NULL pointer on OUTSYMBOLS. We
1875 shouldn't really need one, since we have SYMCOUNT, but some old
1876 code still expects one. */
1877 if (! generic_add_output_symbol (abfd, &outsymalloc, NULL))
1878 return false;
1879
1880 if (bfd_link_relocatable (info))
1881 {
1882 /* Allocate space for the output relocs for each section. */
1883 for (o = abfd->sections; o != NULL; o = o->next)
1884 {
1885 o->reloc_count = 0;
1886 for (p = o->map_head.link_order; p != NULL; p = p->next)
1887 {
1888 if (p->type == bfd_section_reloc_link_order
1889 || p->type == bfd_symbol_reloc_link_order)
1890 ++o->reloc_count;
1891 else if (p->type == bfd_indirect_link_order)
1892 {
1893 asection *input_section;
1894 bfd *input_bfd;
1895 long relsize;
1896 arelent **relocs;
1897 asymbol **symbols;
1898 long reloc_count;
1899
1900 input_section = p->u.indirect.section;
1901 input_bfd = input_section->owner;
1902 relsize = bfd_get_reloc_upper_bound (input_bfd,
1903 input_section);
1904 if (relsize < 0)
1905 return false;
1906 relocs = (arelent **) bfd_malloc (relsize);
1907 if (!relocs && relsize != 0)
1908 return false;
1909 symbols = _bfd_generic_link_get_symbols (input_bfd);
1910 reloc_count = bfd_canonicalize_reloc (input_bfd,
1911 input_section,
1912 relocs,
1913 symbols);
1914 free (relocs);
1915 if (reloc_count < 0)
1916 return false;
1917 BFD_ASSERT ((unsigned long) reloc_count
1918 == input_section->reloc_count);
1919 o->reloc_count += reloc_count;
1920 }
1921 }
1922 if (o->reloc_count > 0)
1923 {
1924 bfd_size_type amt;
1925
1926 amt = o->reloc_count;
1927 amt *= sizeof (arelent *);
1928 o->orelocation = (struct reloc_cache_entry **) bfd_alloc (abfd, amt);
1929 if (!o->orelocation)
1930 return false;
1931 o->flags |= SEC_RELOC;
1932 /* Reset the count so that it can be used as an index
1933 when putting in the output relocs. */
1934 o->reloc_count = 0;
1935 }
1936 }
1937 }
1938
1939 /* Handle all the link order information for the sections. */
1940 for (o = abfd->sections; o != NULL; o = o->next)
1941 {
1942 for (p = o->map_head.link_order; p != NULL; p = p->next)
1943 {
1944 switch (p->type)
1945 {
1946 case bfd_section_reloc_link_order:
1947 case bfd_symbol_reloc_link_order:
1948 if (! _bfd_generic_reloc_link_order (abfd, info, o, p))
1949 return false;
1950 break;
1951 case bfd_indirect_link_order:
1952 if (! default_indirect_link_order (abfd, info, o, p, true))
1953 return false;
1954 break;
1955 default:
1956 if (! _bfd_default_link_order (abfd, info, o, p))
1957 return false;
1958 break;
1959 }
1960 }
1961 }
1962
1963 return true;
1964 }
1965
1966 /* Add an output symbol to the output BFD. */
1967
1968 static bool
generic_add_output_symbol(bfd * output_bfd,size_t * psymalloc,asymbol * sym)1969 generic_add_output_symbol (bfd *output_bfd, size_t *psymalloc, asymbol *sym)
1970 {
1971 if (bfd_get_symcount (output_bfd) >= *psymalloc)
1972 {
1973 asymbol **newsyms;
1974 bfd_size_type amt;
1975
1976 if (*psymalloc == 0)
1977 *psymalloc = 124;
1978 else
1979 *psymalloc *= 2;
1980 amt = *psymalloc;
1981 amt *= sizeof (asymbol *);
1982 newsyms = (asymbol **) bfd_realloc (bfd_get_outsymbols (output_bfd), amt);
1983 if (newsyms == NULL)
1984 return false;
1985 output_bfd->outsymbols = newsyms;
1986 }
1987
1988 output_bfd->outsymbols[output_bfd->symcount] = sym;
1989 if (sym != NULL)
1990 ++output_bfd->symcount;
1991
1992 return true;
1993 }
1994
1995 /* Handle the symbols for an input BFD. */
1996
1997 bool
_bfd_generic_link_output_symbols(bfd * output_bfd,bfd * input_bfd,struct bfd_link_info * info,size_t * psymalloc)1998 _bfd_generic_link_output_symbols (bfd *output_bfd,
1999 bfd *input_bfd,
2000 struct bfd_link_info *info,
2001 size_t *psymalloc)
2002 {
2003 asymbol **sym_ptr;
2004 asymbol **sym_end;
2005
2006 if (!bfd_generic_link_read_symbols (input_bfd))
2007 return false;
2008
2009 /* Create a filename symbol if we are supposed to. */
2010 if (info->create_object_symbols_section != NULL)
2011 {
2012 asection *sec;
2013
2014 for (sec = input_bfd->sections; sec != NULL; sec = sec->next)
2015 {
2016 if (sec->output_section == info->create_object_symbols_section)
2017 {
2018 asymbol *newsym;
2019
2020 newsym = bfd_make_empty_symbol (input_bfd);
2021 if (!newsym)
2022 return false;
2023 newsym->name = bfd_get_filename (input_bfd);
2024 newsym->value = 0;
2025 newsym->flags = BSF_LOCAL | BSF_FILE;
2026 newsym->section = sec;
2027
2028 if (! generic_add_output_symbol (output_bfd, psymalloc,
2029 newsym))
2030 return false;
2031
2032 break;
2033 }
2034 }
2035 }
2036
2037 /* Adjust the values of the globally visible symbols, and write out
2038 local symbols. */
2039 sym_ptr = _bfd_generic_link_get_symbols (input_bfd);
2040 sym_end = sym_ptr + _bfd_generic_link_get_symcount (input_bfd);
2041 for (; sym_ptr < sym_end; sym_ptr++)
2042 {
2043 asymbol *sym;
2044 struct generic_link_hash_entry *h;
2045 bool output;
2046
2047 h = NULL;
2048 sym = *sym_ptr;
2049 if ((sym->flags & (BSF_INDIRECT
2050 | BSF_WARNING
2051 | BSF_GLOBAL
2052 | BSF_CONSTRUCTOR
2053 | BSF_WEAK)) != 0
2054 || bfd_is_und_section (bfd_asymbol_section (sym))
2055 || bfd_is_com_section (bfd_asymbol_section (sym))
2056 || bfd_is_ind_section (bfd_asymbol_section (sym)))
2057 {
2058 if (sym->udata.p != NULL)
2059 h = (struct generic_link_hash_entry *) sym->udata.p;
2060 else if ((sym->flags & BSF_CONSTRUCTOR) != 0)
2061 {
2062 /* This case normally means that the main linker code
2063 deliberately ignored this constructor symbol. We
2064 should just pass it through. This will screw up if
2065 the constructor symbol is from a different,
2066 non-generic, object file format, but the case will
2067 only arise when linking with -r, which will probably
2068 fail anyhow, since there will be no way to represent
2069 the relocs in the output format being used. */
2070 h = NULL;
2071 }
2072 else if (bfd_is_und_section (bfd_asymbol_section (sym)))
2073 h = ((struct generic_link_hash_entry *)
2074 bfd_wrapped_link_hash_lookup (output_bfd, info,
2075 bfd_asymbol_name (sym),
2076 false, false, true));
2077 else
2078 h = _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info),
2079 bfd_asymbol_name (sym),
2080 false, false, true);
2081
2082 if (h != NULL)
2083 {
2084 /* Force all references to this symbol to point to
2085 the same area in memory. It is possible that
2086 this routine will be called with a hash table
2087 other than a generic hash table, so we double
2088 check that. */
2089 if (info->output_bfd->xvec == input_bfd->xvec)
2090 {
2091 if (h->sym != NULL)
2092 *sym_ptr = sym = h->sym;
2093 }
2094
2095 switch (h->root.type)
2096 {
2097 default:
2098 case bfd_link_hash_new:
2099 abort ();
2100 case bfd_link_hash_undefined:
2101 break;
2102 case bfd_link_hash_undefweak:
2103 sym->flags |= BSF_WEAK;
2104 break;
2105 case bfd_link_hash_indirect:
2106 h = (struct generic_link_hash_entry *) h->root.u.i.link;
2107 /* fall through */
2108 case bfd_link_hash_defined:
2109 sym->flags |= BSF_GLOBAL;
2110 sym->flags &=~ (BSF_WEAK | BSF_CONSTRUCTOR);
2111 sym->value = h->root.u.def.value;
2112 sym->section = h->root.u.def.section;
2113 break;
2114 case bfd_link_hash_defweak:
2115 sym->flags |= BSF_WEAK;
2116 sym->flags &=~ BSF_CONSTRUCTOR;
2117 sym->value = h->root.u.def.value;
2118 sym->section = h->root.u.def.section;
2119 break;
2120 case bfd_link_hash_common:
2121 sym->value = h->root.u.c.size;
2122 sym->flags |= BSF_GLOBAL;
2123 if (! bfd_is_com_section (sym->section))
2124 {
2125 BFD_ASSERT (bfd_is_und_section (sym->section));
2126 sym->section = bfd_com_section_ptr;
2127 }
2128 /* We do not set the section of the symbol to
2129 h->root.u.c.p->section. That value was saved so
2130 that we would know where to allocate the symbol
2131 if it was defined. In this case the type is
2132 still bfd_link_hash_common, so we did not define
2133 it, so we do not want to use that section. */
2134 break;
2135 }
2136 }
2137 }
2138
2139 if ((sym->flags & BSF_KEEP) == 0
2140 && (info->strip == strip_all
2141 || (info->strip == strip_some
2142 && bfd_hash_lookup (info->keep_hash, bfd_asymbol_name (sym),
2143 false, false) == NULL)))
2144 output = false;
2145 else if ((sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE)) != 0)
2146 {
2147 /* If this symbol is marked as occurring now, rather
2148 than at the end, output it now. This is used for
2149 COFF C_EXT FCN symbols. FIXME: There must be a
2150 better way. */
2151 if (bfd_asymbol_bfd (sym) == input_bfd
2152 && (sym->flags & BSF_NOT_AT_END) != 0)
2153 output = true;
2154 else
2155 output = false;
2156 }
2157 else if ((sym->flags & BSF_KEEP) != 0)
2158 output = true;
2159 else if (bfd_is_ind_section (sym->section))
2160 output = false;
2161 else if ((sym->flags & BSF_DEBUGGING) != 0)
2162 {
2163 if (info->strip == strip_none)
2164 output = true;
2165 else
2166 output = false;
2167 }
2168 else if (bfd_is_und_section (sym->section)
2169 || bfd_is_com_section (sym->section))
2170 output = false;
2171 else if ((sym->flags & BSF_LOCAL) != 0)
2172 {
2173 if ((sym->flags & BSF_WARNING) != 0)
2174 output = false;
2175 else
2176 {
2177 switch (info->discard)
2178 {
2179 default:
2180 case discard_all:
2181 output = false;
2182 break;
2183 case discard_sec_merge:
2184 output = true;
2185 if (bfd_link_relocatable (info)
2186 || ! (sym->section->flags & SEC_MERGE))
2187 break;
2188 /* FALLTHROUGH */
2189 case discard_l:
2190 if (bfd_is_local_label (input_bfd, sym))
2191 output = false;
2192 else
2193 output = true;
2194 break;
2195 case discard_none:
2196 output = true;
2197 break;
2198 }
2199 }
2200 }
2201 else if ((sym->flags & BSF_CONSTRUCTOR))
2202 {
2203 if (info->strip != strip_all)
2204 output = true;
2205 else
2206 output = false;
2207 }
2208 else if (sym->flags == 0
2209 && (sym->section->owner->flags & BFD_PLUGIN) != 0)
2210 /* LTO doesn't set symbol information. We get here with the
2211 generic linker for a symbol that was "common" but no longer
2212 needs to be global. */
2213 output = false;
2214 else
2215 abort ();
2216
2217 /* If this symbol is in a section which is not being included
2218 in the output file, then we don't want to output the
2219 symbol. */
2220 if (!bfd_is_abs_section (sym->section)
2221 && bfd_section_removed_from_list (output_bfd,
2222 sym->section->output_section))
2223 output = false;
2224
2225 if (output)
2226 {
2227 if (! generic_add_output_symbol (output_bfd, psymalloc, sym))
2228 return false;
2229 if (h != NULL)
2230 h->written = true;
2231 }
2232 }
2233
2234 return true;
2235 }
2236
2237 /* Set the section and value of a generic BFD symbol based on a linker
2238 hash table entry. */
2239
2240 static void
set_symbol_from_hash(asymbol * sym,struct bfd_link_hash_entry * h)2241 set_symbol_from_hash (asymbol *sym, struct bfd_link_hash_entry *h)
2242 {
2243 switch (h->type)
2244 {
2245 default:
2246 abort ();
2247 break;
2248 case bfd_link_hash_new:
2249 /* This can happen when a constructor symbol is seen but we are
2250 not building constructors. */
2251 if (sym->section != NULL)
2252 {
2253 BFD_ASSERT ((sym->flags & BSF_CONSTRUCTOR) != 0);
2254 }
2255 else
2256 {
2257 sym->flags |= BSF_CONSTRUCTOR;
2258 sym->section = bfd_abs_section_ptr;
2259 sym->value = 0;
2260 }
2261 break;
2262 case bfd_link_hash_undefined:
2263 sym->section = bfd_und_section_ptr;
2264 sym->value = 0;
2265 break;
2266 case bfd_link_hash_undefweak:
2267 sym->section = bfd_und_section_ptr;
2268 sym->value = 0;
2269 sym->flags |= BSF_WEAK;
2270 break;
2271 case bfd_link_hash_defined:
2272 sym->section = h->u.def.section;
2273 sym->value = h->u.def.value;
2274 break;
2275 case bfd_link_hash_defweak:
2276 sym->flags |= BSF_WEAK;
2277 sym->section = h->u.def.section;
2278 sym->value = h->u.def.value;
2279 break;
2280 case bfd_link_hash_common:
2281 sym->value = h->u.c.size;
2282 if (sym->section == NULL)
2283 sym->section = bfd_com_section_ptr;
2284 else if (! bfd_is_com_section (sym->section))
2285 {
2286 BFD_ASSERT (bfd_is_und_section (sym->section));
2287 sym->section = bfd_com_section_ptr;
2288 }
2289 /* Do not set the section; see _bfd_generic_link_output_symbols. */
2290 break;
2291 case bfd_link_hash_indirect:
2292 case bfd_link_hash_warning:
2293 /* FIXME: What should we do here? */
2294 break;
2295 }
2296 }
2297
2298 /* Write out a global symbol, if it hasn't already been written out.
2299 This is called for each symbol in the hash table. */
2300
2301 bool
_bfd_generic_link_write_global_symbol(struct generic_link_hash_entry * h,void * data)2302 _bfd_generic_link_write_global_symbol (struct generic_link_hash_entry *h,
2303 void *data)
2304 {
2305 struct generic_write_global_symbol_info *wginfo =
2306 (struct generic_write_global_symbol_info *) data;
2307 asymbol *sym;
2308
2309 if (h->written)
2310 return true;
2311
2312 h->written = true;
2313
2314 if (wginfo->info->strip == strip_all
2315 || (wginfo->info->strip == strip_some
2316 && bfd_hash_lookup (wginfo->info->keep_hash, h->root.root.string,
2317 false, false) == NULL))
2318 return true;
2319
2320 if (h->sym != NULL)
2321 sym = h->sym;
2322 else
2323 {
2324 sym = bfd_make_empty_symbol (wginfo->output_bfd);
2325 if (!sym)
2326 return false;
2327 sym->name = h->root.root.string;
2328 sym->flags = 0;
2329 }
2330
2331 set_symbol_from_hash (sym, &h->root);
2332
2333 sym->flags |= BSF_GLOBAL;
2334
2335 if (! generic_add_output_symbol (wginfo->output_bfd, wginfo->psymalloc,
2336 sym))
2337 {
2338 /* FIXME: No way to return failure. */
2339 abort ();
2340 }
2341
2342 return true;
2343 }
2344
2345 /* Create a relocation. */
2346
2347 bool
_bfd_generic_reloc_link_order(bfd * abfd,struct bfd_link_info * info,asection * sec,struct bfd_link_order * link_order)2348 _bfd_generic_reloc_link_order (bfd *abfd,
2349 struct bfd_link_info *info,
2350 asection *sec,
2351 struct bfd_link_order *link_order)
2352 {
2353 arelent *r;
2354
2355 if (! bfd_link_relocatable (info))
2356 abort ();
2357 if (sec->orelocation == NULL)
2358 abort ();
2359
2360 r = (arelent *) bfd_alloc (abfd, sizeof (arelent));
2361 if (r == NULL)
2362 return false;
2363
2364 r->address = link_order->offset;
2365 r->howto = bfd_reloc_type_lookup (abfd, link_order->u.reloc.p->reloc);
2366 if (r->howto == 0)
2367 {
2368 bfd_set_error (bfd_error_bad_value);
2369 return false;
2370 }
2371
2372 /* Get the symbol to use for the relocation. */
2373 if (link_order->type == bfd_section_reloc_link_order)
2374 r->sym_ptr_ptr = link_order->u.reloc.p->u.section->symbol_ptr_ptr;
2375 else
2376 {
2377 struct generic_link_hash_entry *h;
2378
2379 h = ((struct generic_link_hash_entry *)
2380 bfd_wrapped_link_hash_lookup (abfd, info,
2381 link_order->u.reloc.p->u.name,
2382 false, false, true));
2383 if (h == NULL
2384 || ! h->written)
2385 {
2386 (*info->callbacks->unattached_reloc)
2387 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0);
2388 bfd_set_error (bfd_error_bad_value);
2389 return false;
2390 }
2391 r->sym_ptr_ptr = &h->sym;
2392 }
2393
2394 /* If this is an inplace reloc, write the addend to the object file.
2395 Otherwise, store it in the reloc addend. */
2396 if (! r->howto->partial_inplace)
2397 r->addend = link_order->u.reloc.p->addend;
2398 else
2399 {
2400 bfd_size_type size;
2401 bfd_reloc_status_type rstat;
2402 bfd_byte *buf;
2403 bool ok;
2404 file_ptr loc;
2405
2406 size = bfd_get_reloc_size (r->howto);
2407 buf = (bfd_byte *) bfd_zmalloc (size);
2408 if (buf == NULL && size != 0)
2409 return false;
2410 rstat = _bfd_relocate_contents (r->howto, abfd,
2411 (bfd_vma) link_order->u.reloc.p->addend,
2412 buf);
2413 switch (rstat)
2414 {
2415 case bfd_reloc_ok:
2416 break;
2417 default:
2418 case bfd_reloc_outofrange:
2419 abort ();
2420 case bfd_reloc_overflow:
2421 (*info->callbacks->reloc_overflow)
2422 (info, NULL,
2423 (link_order->type == bfd_section_reloc_link_order
2424 ? bfd_section_name (link_order->u.reloc.p->u.section)
2425 : link_order->u.reloc.p->u.name),
2426 r->howto->name, link_order->u.reloc.p->addend,
2427 NULL, NULL, 0);
2428 break;
2429 }
2430 loc = link_order->offset * bfd_octets_per_byte (abfd, sec);
2431 ok = bfd_set_section_contents (abfd, sec, buf, loc, size);
2432 free (buf);
2433 if (! ok)
2434 return false;
2435
2436 r->addend = 0;
2437 }
2438
2439 sec->orelocation[sec->reloc_count] = r;
2440 ++sec->reloc_count;
2441
2442 return true;
2443 }
2444
2445 /* Allocate a new link_order for a section. */
2446
2447 struct bfd_link_order *
bfd_new_link_order(bfd * abfd,asection * section)2448 bfd_new_link_order (bfd *abfd, asection *section)
2449 {
2450 size_t amt = sizeof (struct bfd_link_order);
2451 struct bfd_link_order *new_lo;
2452
2453 new_lo = (struct bfd_link_order *) bfd_zalloc (abfd, amt);
2454 if (!new_lo)
2455 return NULL;
2456
2457 new_lo->type = bfd_undefined_link_order;
2458
2459 if (section->map_tail.link_order != NULL)
2460 section->map_tail.link_order->next = new_lo;
2461 else
2462 section->map_head.link_order = new_lo;
2463 section->map_tail.link_order = new_lo;
2464
2465 return new_lo;
2466 }
2467
2468 /* Default link order processing routine. Note that we can not handle
2469 the reloc_link_order types here, since they depend upon the details
2470 of how the particular backends generates relocs. */
2471
2472 bool
_bfd_default_link_order(bfd * abfd,struct bfd_link_info * info,asection * sec,struct bfd_link_order * link_order)2473 _bfd_default_link_order (bfd *abfd,
2474 struct bfd_link_info *info,
2475 asection *sec,
2476 struct bfd_link_order *link_order)
2477 {
2478 switch (link_order->type)
2479 {
2480 case bfd_undefined_link_order:
2481 case bfd_section_reloc_link_order:
2482 case bfd_symbol_reloc_link_order:
2483 default:
2484 abort ();
2485 case bfd_indirect_link_order:
2486 return default_indirect_link_order (abfd, info, sec, link_order,
2487 false);
2488 case bfd_data_link_order:
2489 return default_data_link_order (abfd, info, sec, link_order);
2490 }
2491 }
2492
2493 /* Default routine to handle a bfd_data_link_order. */
2494
2495 static bool
default_data_link_order(bfd * abfd,struct bfd_link_info * info,asection * sec,struct bfd_link_order * link_order)2496 default_data_link_order (bfd *abfd,
2497 struct bfd_link_info *info,
2498 asection *sec,
2499 struct bfd_link_order *link_order)
2500 {
2501 bfd_size_type size;
2502 size_t fill_size;
2503 bfd_byte *fill;
2504 file_ptr loc;
2505 bool result;
2506
2507 BFD_ASSERT ((sec->flags & SEC_HAS_CONTENTS) != 0);
2508
2509 size = link_order->size;
2510 if (size == 0)
2511 return true;
2512
2513 fill = link_order->u.data.contents;
2514 fill_size = link_order->u.data.size;
2515 if (fill_size == 0)
2516 {
2517 fill = abfd->arch_info->fill (size, info->big_endian,
2518 (sec->flags & SEC_CODE) != 0);
2519 if (fill == NULL)
2520 return false;
2521 }
2522 else if (fill_size < size)
2523 {
2524 bfd_byte *p;
2525 fill = (bfd_byte *) bfd_malloc (size);
2526 if (fill == NULL)
2527 return false;
2528 p = fill;
2529 if (fill_size == 1)
2530 memset (p, (int) link_order->u.data.contents[0], (size_t) size);
2531 else
2532 {
2533 do
2534 {
2535 memcpy (p, link_order->u.data.contents, fill_size);
2536 p += fill_size;
2537 size -= fill_size;
2538 }
2539 while (size >= fill_size);
2540 if (size != 0)
2541 memcpy (p, link_order->u.data.contents, (size_t) size);
2542 size = link_order->size;
2543 }
2544 }
2545
2546 loc = link_order->offset * bfd_octets_per_byte (abfd, sec);
2547 result = bfd_set_section_contents (abfd, sec, fill, loc, size);
2548
2549 if (fill != link_order->u.data.contents)
2550 free (fill);
2551 return result;
2552 }
2553
2554 /* Default routine to handle a bfd_indirect_link_order. */
2555
2556 static bool
default_indirect_link_order(bfd * output_bfd,struct bfd_link_info * info,asection * output_section,struct bfd_link_order * link_order,bool generic_linker)2557 default_indirect_link_order (bfd *output_bfd,
2558 struct bfd_link_info *info,
2559 asection *output_section,
2560 struct bfd_link_order *link_order,
2561 bool generic_linker)
2562 {
2563 asection *input_section;
2564 bfd *input_bfd;
2565 bfd_byte *alloced = NULL;
2566 bfd_byte *new_contents;
2567 file_ptr loc;
2568
2569 BFD_ASSERT ((output_section->flags & SEC_HAS_CONTENTS) != 0);
2570
2571 input_section = link_order->u.indirect.section;
2572 input_bfd = input_section->owner;
2573 if (input_section->size == 0)
2574 return true;
2575
2576 BFD_ASSERT (input_section->output_section == output_section);
2577 BFD_ASSERT (input_section->output_offset == link_order->offset);
2578 BFD_ASSERT (input_section->size == link_order->size);
2579
2580 if (bfd_link_relocatable (info)
2581 && input_section->reloc_count > 0
2582 && output_section->orelocation == NULL)
2583 {
2584 /* Space has not been allocated for the output relocations.
2585 This can happen when we are called by a specific backend
2586 because somebody is attempting to link together different
2587 types of object files. Handling this case correctly is
2588 difficult, and sometimes impossible. */
2589 _bfd_error_handler
2590 /* xgettext:c-format */
2591 (_("attempt to do relocatable link with %s input and %s output"),
2592 bfd_get_target (input_bfd), bfd_get_target (output_bfd));
2593 bfd_set_error (bfd_error_wrong_format);
2594 return false;
2595 }
2596
2597 if (! generic_linker)
2598 {
2599 asymbol **sympp;
2600 asymbol **symppend;
2601
2602 /* Get the canonical symbols. The generic linker will always
2603 have retrieved them by this point, but we are being called by
2604 a specific linker, presumably because we are linking
2605 different types of object files together. */
2606 if (!bfd_generic_link_read_symbols (input_bfd))
2607 return false;
2608
2609 /* Since we have been called by a specific linker, rather than
2610 the generic linker, the values of the symbols will not be
2611 right. They will be the values as seen in the input file,
2612 not the values of the final link. We need to fix them up
2613 before we can relocate the section. */
2614 sympp = _bfd_generic_link_get_symbols (input_bfd);
2615 symppend = sympp + _bfd_generic_link_get_symcount (input_bfd);
2616 for (; sympp < symppend; sympp++)
2617 {
2618 asymbol *sym;
2619 struct bfd_link_hash_entry *h;
2620
2621 sym = *sympp;
2622
2623 if ((sym->flags & (BSF_INDIRECT
2624 | BSF_WARNING
2625 | BSF_GLOBAL
2626 | BSF_CONSTRUCTOR
2627 | BSF_WEAK)) != 0
2628 || bfd_is_und_section (bfd_asymbol_section (sym))
2629 || bfd_is_com_section (bfd_asymbol_section (sym))
2630 || bfd_is_ind_section (bfd_asymbol_section (sym)))
2631 {
2632 /* sym->udata may have been set by
2633 generic_link_add_symbol_list. */
2634 if (sym->udata.p != NULL)
2635 h = (struct bfd_link_hash_entry *) sym->udata.p;
2636 else if (bfd_is_und_section (bfd_asymbol_section (sym)))
2637 h = bfd_wrapped_link_hash_lookup (output_bfd, info,
2638 bfd_asymbol_name (sym),
2639 false, false, true);
2640 else
2641 h = bfd_link_hash_lookup (info->hash,
2642 bfd_asymbol_name (sym),
2643 false, false, true);
2644 if (h != NULL)
2645 set_symbol_from_hash (sym, h);
2646 }
2647 }
2648 }
2649
2650 if ((output_section->flags & (SEC_GROUP | SEC_LINKER_CREATED)) == SEC_GROUP
2651 && input_section->size != 0)
2652 {
2653 /* Group section contents are set by bfd_elf_set_group_contents. */
2654 if (!output_bfd->output_has_begun)
2655 {
2656 /* FIXME: This hack ensures bfd_elf_set_group_contents is called. */
2657 if (!bfd_set_section_contents (output_bfd, output_section, "", 0, 1))
2658 goto error_return;
2659 }
2660 new_contents = output_section->contents;
2661 BFD_ASSERT (new_contents != NULL);
2662 BFD_ASSERT (input_section->output_offset == 0);
2663 }
2664 else
2665 {
2666 /* Get and relocate the section contents. */
2667 new_contents = (bfd_get_relocated_section_contents
2668 (output_bfd, info, link_order, NULL,
2669 bfd_link_relocatable (info),
2670 _bfd_generic_link_get_symbols (input_bfd)));
2671 alloced = new_contents;
2672 if (!new_contents)
2673 goto error_return;
2674 }
2675
2676 /* Output the section contents. */
2677 loc = (input_section->output_offset
2678 * bfd_octets_per_byte (output_bfd, output_section));
2679 if (! bfd_set_section_contents (output_bfd, output_section,
2680 new_contents, loc, input_section->size))
2681 goto error_return;
2682
2683 free (alloced);
2684 return true;
2685
2686 error_return:
2687 free (alloced);
2688 return false;
2689 }
2690
2691 /* A little routine to count the number of relocs in a link_order
2692 list. */
2693
2694 unsigned int
_bfd_count_link_order_relocs(struct bfd_link_order * link_order)2695 _bfd_count_link_order_relocs (struct bfd_link_order *link_order)
2696 {
2697 register unsigned int c;
2698 register struct bfd_link_order *l;
2699
2700 c = 0;
2701 for (l = link_order; l != NULL; l = l->next)
2702 {
2703 if (l->type == bfd_section_reloc_link_order
2704 || l->type == bfd_symbol_reloc_link_order)
2705 ++c;
2706 }
2707
2708 return c;
2709 }
2710
2711 /*
2712 FUNCTION
2713 bfd_link_split_section
2714
2715 SYNOPSIS
2716 bool bfd_link_split_section (bfd *abfd, asection *sec);
2717
2718 DESCRIPTION
2719 Return nonzero if @var{sec} should be split during a
2720 reloceatable or final link.
2721
2722 .#define bfd_link_split_section(abfd, sec) \
2723 . BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec))
2724 .
2725
2726 */
2727
2728 bool
_bfd_generic_link_split_section(bfd * abfd ATTRIBUTE_UNUSED,asection * sec ATTRIBUTE_UNUSED)2729 _bfd_generic_link_split_section (bfd *abfd ATTRIBUTE_UNUSED,
2730 asection *sec ATTRIBUTE_UNUSED)
2731 {
2732 return false;
2733 }
2734
2735 /*
2736 FUNCTION
2737 bfd_section_already_linked
2738
2739 SYNOPSIS
2740 bool bfd_section_already_linked (bfd *abfd,
2741 asection *sec,
2742 struct bfd_link_info *info);
2743
2744 DESCRIPTION
2745 Check if @var{data} has been already linked during a reloceatable
2746 or final link. Return TRUE if it has.
2747
2748 .#define bfd_section_already_linked(abfd, sec, info) \
2749 . BFD_SEND (abfd, _section_already_linked, (abfd, sec, info))
2750 .
2751
2752 */
2753
2754 /* Sections marked with the SEC_LINK_ONCE flag should only be linked
2755 once into the output. This routine checks each section, and
2756 arrange to discard it if a section of the same name has already
2757 been linked. This code assumes that all relevant sections have the
2758 SEC_LINK_ONCE flag set; that is, it does not depend solely upon the
2759 section name. bfd_section_already_linked is called via
2760 bfd_map_over_sections. */
2761
2762 /* The hash table. */
2763
2764 static struct bfd_hash_table _bfd_section_already_linked_table;
2765
2766 /* Support routines for the hash table used by section_already_linked,
2767 initialize the table, traverse, lookup, fill in an entry and remove
2768 the table. */
2769
2770 void
bfd_section_already_linked_table_traverse(bool (* func)(struct bfd_section_already_linked_hash_entry *,void *),void * info)2771 bfd_section_already_linked_table_traverse
2772 (bool (*func) (struct bfd_section_already_linked_hash_entry *, void *),
2773 void *info)
2774 {
2775 bfd_hash_traverse (&_bfd_section_already_linked_table,
2776 (bool (*) (struct bfd_hash_entry *, void *)) func,
2777 info);
2778 }
2779
2780 struct bfd_section_already_linked_hash_entry *
bfd_section_already_linked_table_lookup(const char * name)2781 bfd_section_already_linked_table_lookup (const char *name)
2782 {
2783 return ((struct bfd_section_already_linked_hash_entry *)
2784 bfd_hash_lookup (&_bfd_section_already_linked_table, name,
2785 true, false));
2786 }
2787
2788 bool
bfd_section_already_linked_table_insert(struct bfd_section_already_linked_hash_entry * already_linked_list,asection * sec)2789 bfd_section_already_linked_table_insert
2790 (struct bfd_section_already_linked_hash_entry *already_linked_list,
2791 asection *sec)
2792 {
2793 struct bfd_section_already_linked *l;
2794
2795 /* Allocate the memory from the same obstack as the hash table is
2796 kept in. */
2797 l = (struct bfd_section_already_linked *)
2798 bfd_hash_allocate (&_bfd_section_already_linked_table, sizeof *l);
2799 if (l == NULL)
2800 return false;
2801 l->sec = sec;
2802 l->next = already_linked_list->entry;
2803 already_linked_list->entry = l;
2804 return true;
2805 }
2806
2807 static struct bfd_hash_entry *
already_linked_newfunc(struct bfd_hash_entry * entry ATTRIBUTE_UNUSED,struct bfd_hash_table * table,const char * string ATTRIBUTE_UNUSED)2808 already_linked_newfunc (struct bfd_hash_entry *entry ATTRIBUTE_UNUSED,
2809 struct bfd_hash_table *table,
2810 const char *string ATTRIBUTE_UNUSED)
2811 {
2812 struct bfd_section_already_linked_hash_entry *ret =
2813 (struct bfd_section_already_linked_hash_entry *)
2814 bfd_hash_allocate (table, sizeof *ret);
2815
2816 if (ret == NULL)
2817 return NULL;
2818
2819 ret->entry = NULL;
2820
2821 return &ret->root;
2822 }
2823
2824 bool
bfd_section_already_linked_table_init(void)2825 bfd_section_already_linked_table_init (void)
2826 {
2827 return bfd_hash_table_init_n (&_bfd_section_already_linked_table,
2828 already_linked_newfunc,
2829 sizeof (struct bfd_section_already_linked_hash_entry),
2830 42);
2831 }
2832
2833 void
bfd_section_already_linked_table_free(void)2834 bfd_section_already_linked_table_free (void)
2835 {
2836 bfd_hash_table_free (&_bfd_section_already_linked_table);
2837 }
2838
2839 /* Report warnings as appropriate for duplicate section SEC.
2840 Return FALSE if we decide to keep SEC after all. */
2841
2842 bool
_bfd_handle_already_linked(asection * sec,struct bfd_section_already_linked * l,struct bfd_link_info * info)2843 _bfd_handle_already_linked (asection *sec,
2844 struct bfd_section_already_linked *l,
2845 struct bfd_link_info *info)
2846 {
2847 switch (sec->flags & SEC_LINK_DUPLICATES)
2848 {
2849 default:
2850 abort ();
2851
2852 case SEC_LINK_DUPLICATES_DISCARD:
2853 /* If we found an LTO IR match for this comdat group on
2854 the first pass, replace it with the LTO output on the
2855 second pass. We can't simply choose real object
2856 files over IR because the first pass may contain a
2857 mix of LTO and normal objects and we must keep the
2858 first match, be it IR or real. */
2859 if (sec->owner->lto_output
2860 && (l->sec->owner->flags & BFD_PLUGIN) != 0)
2861 {
2862 l->sec = sec;
2863 return false;
2864 }
2865 break;
2866
2867 case SEC_LINK_DUPLICATES_ONE_ONLY:
2868 info->callbacks->einfo
2869 /* xgettext:c-format */
2870 (_("%pB: ignoring duplicate section `%pA'\n"),
2871 sec->owner, sec);
2872 break;
2873
2874 case SEC_LINK_DUPLICATES_SAME_SIZE:
2875 if ((l->sec->owner->flags & BFD_PLUGIN) != 0)
2876 ;
2877 else if (sec->size != l->sec->size)
2878 info->callbacks->einfo
2879 /* xgettext:c-format */
2880 (_("%pB: duplicate section `%pA' has different size\n"),
2881 sec->owner, sec);
2882 break;
2883
2884 case SEC_LINK_DUPLICATES_SAME_CONTENTS:
2885 if ((l->sec->owner->flags & BFD_PLUGIN) != 0)
2886 ;
2887 else if (sec->size != l->sec->size)
2888 info->callbacks->einfo
2889 /* xgettext:c-format */
2890 (_("%pB: duplicate section `%pA' has different size\n"),
2891 sec->owner, sec);
2892 else if (sec->size != 0)
2893 {
2894 bfd_byte *sec_contents, *l_sec_contents;
2895
2896 if ((sec->flags & SEC_HAS_CONTENTS) == 0
2897 && (l->sec->flags & SEC_HAS_CONTENTS) == 0)
2898 ;
2899 else if ((sec->flags & SEC_HAS_CONTENTS) == 0
2900 || !bfd_malloc_and_get_section (sec->owner, sec,
2901 &sec_contents))
2902 info->callbacks->einfo
2903 /* xgettext:c-format */
2904 (_("%pB: could not read contents of section `%pA'\n"),
2905 sec->owner, sec);
2906 else if ((l->sec->flags & SEC_HAS_CONTENTS) == 0
2907 || !bfd_malloc_and_get_section (l->sec->owner, l->sec,
2908 &l_sec_contents))
2909 {
2910 info->callbacks->einfo
2911 /* xgettext:c-format */
2912 (_("%pB: could not read contents of section `%pA'\n"),
2913 l->sec->owner, l->sec);
2914 free (sec_contents);
2915 }
2916 else
2917 {
2918 if (memcmp (sec_contents, l_sec_contents, sec->size) != 0)
2919 info->callbacks->einfo
2920 /* xgettext:c-format */
2921 (_("%pB: duplicate section `%pA' has different contents\n"),
2922 sec->owner, sec);
2923 free (l_sec_contents);
2924 free (sec_contents);
2925 }
2926 }
2927 break;
2928 }
2929
2930 /* Set the output_section field so that lang_add_section
2931 does not create a lang_input_section structure for this
2932 section. Since there might be a symbol in the section
2933 being discarded, we must retain a pointer to the section
2934 which we are really going to use. */
2935 sec->output_section = bfd_abs_section_ptr;
2936 sec->kept_section = l->sec;
2937 return true;
2938 }
2939
2940 /* This is used on non-ELF inputs. */
2941
2942 bool
_bfd_generic_section_already_linked(bfd * abfd ATTRIBUTE_UNUSED,asection * sec,struct bfd_link_info * info)2943 _bfd_generic_section_already_linked (bfd *abfd ATTRIBUTE_UNUSED,
2944 asection *sec,
2945 struct bfd_link_info *info)
2946 {
2947 const char *name;
2948 struct bfd_section_already_linked *l;
2949 struct bfd_section_already_linked_hash_entry *already_linked_list;
2950
2951 if ((sec->flags & SEC_LINK_ONCE) == 0)
2952 return false;
2953
2954 /* The generic linker doesn't handle section groups. */
2955 if ((sec->flags & SEC_GROUP) != 0)
2956 return false;
2957
2958 /* FIXME: When doing a relocatable link, we may have trouble
2959 copying relocations in other sections that refer to local symbols
2960 in the section being discarded. Those relocations will have to
2961 be converted somehow; as of this writing I'm not sure that any of
2962 the backends handle that correctly.
2963
2964 It is tempting to instead not discard link once sections when
2965 doing a relocatable link (technically, they should be discarded
2966 whenever we are building constructors). However, that fails,
2967 because the linker winds up combining all the link once sections
2968 into a single large link once section, which defeats the purpose
2969 of having link once sections in the first place. */
2970
2971 name = bfd_section_name (sec);
2972
2973 already_linked_list = bfd_section_already_linked_table_lookup (name);
2974
2975 l = already_linked_list->entry;
2976 if (l != NULL)
2977 {
2978 /* The section has already been linked. See if we should
2979 issue a warning. */
2980 return _bfd_handle_already_linked (sec, l, info);
2981 }
2982
2983 /* This is the first section with this name. Record it. */
2984 if (!bfd_section_already_linked_table_insert (already_linked_list, sec))
2985 info->callbacks->einfo (_("%F%P: already_linked_table: %E\n"));
2986 return false;
2987 }
2988
2989 /* Choose a neighbouring section to S in OBFD that will be output, or
2990 the absolute section if ADDR is out of bounds of the neighbours. */
2991
2992 asection *
_bfd_nearby_section(bfd * obfd,asection * s,bfd_vma addr)2993 _bfd_nearby_section (bfd *obfd, asection *s, bfd_vma addr)
2994 {
2995 asection *next, *prev, *best;
2996
2997 /* Find preceding kept section. */
2998 for (prev = s->prev; prev != NULL; prev = prev->prev)
2999 if ((prev->flags & SEC_EXCLUDE) == 0
3000 && !bfd_section_removed_from_list (obfd, prev))
3001 break;
3002
3003 /* Find following kept section. Start at prev->next because
3004 other sections may have been added after S was removed. */
3005 if (s->prev != NULL)
3006 next = s->prev->next;
3007 else
3008 next = s->owner->sections;
3009 for (; next != NULL; next = next->next)
3010 if ((next->flags & SEC_EXCLUDE) == 0
3011 && !bfd_section_removed_from_list (obfd, next))
3012 break;
3013
3014 /* Choose better of two sections, based on flags. The idea
3015 is to choose a section that will be in the same segment
3016 as S would have been if it was kept. */
3017 best = next;
3018 if (prev == NULL)
3019 {
3020 if (next == NULL)
3021 best = bfd_abs_section_ptr;
3022 }
3023 else if (next == NULL)
3024 best = prev;
3025 else if (((prev->flags ^ next->flags)
3026 & (SEC_ALLOC | SEC_THREAD_LOCAL | SEC_LOAD)) != 0)
3027 {
3028 if (((next->flags ^ s->flags)
3029 & (SEC_ALLOC | SEC_THREAD_LOCAL)) != 0
3030 /* We prefer to choose a loaded section. Section S
3031 doesn't have SEC_LOAD set (it being excluded, that
3032 part of the flag processing didn't happen) so we
3033 can't compare that flag to those of NEXT and PREV. */
3034 || ((prev->flags & SEC_LOAD) != 0
3035 && (next->flags & SEC_LOAD) == 0))
3036 best = prev;
3037 }
3038 else if (((prev->flags ^ next->flags) & SEC_READONLY) != 0)
3039 {
3040 if (((next->flags ^ s->flags) & SEC_READONLY) != 0)
3041 best = prev;
3042 }
3043 else if (((prev->flags ^ next->flags) & SEC_CODE) != 0)
3044 {
3045 if (((next->flags ^ s->flags) & SEC_CODE) != 0)
3046 best = prev;
3047 }
3048 else
3049 {
3050 /* Flags we care about are the same. Prefer the following
3051 section if that will result in a positive valued sym. */
3052 if (addr < next->vma)
3053 best = prev;
3054 }
3055
3056 return best;
3057 }
3058
3059 /* Convert symbols in excluded output sections to use a kept section. */
3060
3061 static bool
fix_syms(struct bfd_link_hash_entry * h,void * data)3062 fix_syms (struct bfd_link_hash_entry *h, void *data)
3063 {
3064 bfd *obfd = (bfd *) data;
3065
3066 if (h->type == bfd_link_hash_defined
3067 || h->type == bfd_link_hash_defweak)
3068 {
3069 asection *s = h->u.def.section;
3070 if (s != NULL
3071 && s->output_section != NULL
3072 && (s->output_section->flags & SEC_EXCLUDE) != 0
3073 && bfd_section_removed_from_list (obfd, s->output_section))
3074 {
3075 asection *op;
3076
3077 h->u.def.value += s->output_offset + s->output_section->vma;
3078 op = _bfd_nearby_section (obfd, s->output_section, h->u.def.value);
3079 h->u.def.value -= op->vma;
3080 h->u.def.section = op;
3081 }
3082 }
3083
3084 return true;
3085 }
3086
3087 void
_bfd_fix_excluded_sec_syms(bfd * obfd,struct bfd_link_info * info)3088 _bfd_fix_excluded_sec_syms (bfd *obfd, struct bfd_link_info *info)
3089 {
3090 bfd_link_hash_traverse (info->hash, fix_syms, obfd);
3091 }
3092
3093 /*
3094 FUNCTION
3095 bfd_generic_define_common_symbol
3096
3097 SYNOPSIS
3098 bool bfd_generic_define_common_symbol
3099 (bfd *output_bfd, struct bfd_link_info *info,
3100 struct bfd_link_hash_entry *h);
3101
3102 DESCRIPTION
3103 Convert common symbol @var{h} into a defined symbol.
3104 Return TRUE on success and FALSE on failure.
3105
3106 .#define bfd_define_common_symbol(output_bfd, info, h) \
3107 . BFD_SEND (output_bfd, _bfd_define_common_symbol, (output_bfd, info, h))
3108 .
3109 */
3110
3111 bool
bfd_generic_define_common_symbol(bfd * output_bfd,struct bfd_link_info * info ATTRIBUTE_UNUSED,struct bfd_link_hash_entry * h)3112 bfd_generic_define_common_symbol (bfd *output_bfd,
3113 struct bfd_link_info *info ATTRIBUTE_UNUSED,
3114 struct bfd_link_hash_entry *h)
3115 {
3116 unsigned int power_of_two;
3117 bfd_vma alignment, size;
3118 asection *section;
3119
3120 BFD_ASSERT (h != NULL && h->type == bfd_link_hash_common);
3121
3122 size = h->u.c.size;
3123 power_of_two = h->u.c.p->alignment_power;
3124 section = h->u.c.p->section;
3125
3126 /* Increase the size of the section to align the common symbol.
3127 The alignment must be a power of two. But if the section does
3128 not have any alignment requirement then do not increase the
3129 alignment unnecessarily. */
3130 if (power_of_two)
3131 alignment = bfd_octets_per_byte (output_bfd, section) << power_of_two;
3132 else
3133 alignment = 1;
3134 BFD_ASSERT (alignment != 0 && (alignment & -alignment) == alignment);
3135 section->size += alignment - 1;
3136 section->size &= -alignment;
3137
3138 /* Adjust the section's overall alignment if necessary. */
3139 if (power_of_two > section->alignment_power)
3140 section->alignment_power = power_of_two;
3141
3142 /* Change the symbol from common to defined. */
3143 h->type = bfd_link_hash_defined;
3144 h->u.def.section = section;
3145 h->u.def.value = section->size;
3146
3147 /* Increase the size of the section. */
3148 section->size += size;
3149
3150 /* Make sure the section is allocated in memory, and make sure that
3151 it is no longer a common section. */
3152 section->flags |= SEC_ALLOC;
3153 section->flags &= ~(SEC_IS_COMMON | SEC_HAS_CONTENTS);
3154 return true;
3155 }
3156
3157 /*
3158 FUNCTION
3159 _bfd_generic_link_hide_symbol
3160
3161 SYNOPSIS
3162 void _bfd_generic_link_hide_symbol
3163 (bfd *output_bfd, struct bfd_link_info *info,
3164 struct bfd_link_hash_entry *h);
3165
3166 DESCRIPTION
3167 Hide symbol @var{h}.
3168 This is an internal function. It should not be called from
3169 outside the BFD library.
3170
3171 .#define bfd_link_hide_symbol(output_bfd, info, h) \
3172 . BFD_SEND (output_bfd, _bfd_link_hide_symbol, (output_bfd, info, h))
3173 .
3174 */
3175
3176 void
_bfd_generic_link_hide_symbol(bfd * output_bfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED,struct bfd_link_hash_entry * h ATTRIBUTE_UNUSED)3177 _bfd_generic_link_hide_symbol (bfd *output_bfd ATTRIBUTE_UNUSED,
3178 struct bfd_link_info *info ATTRIBUTE_UNUSED,
3179 struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED)
3180 {
3181 }
3182
3183 /*
3184 FUNCTION
3185 bfd_generic_define_start_stop
3186
3187 SYNOPSIS
3188 struct bfd_link_hash_entry *bfd_generic_define_start_stop
3189 (struct bfd_link_info *info,
3190 const char *symbol, asection *sec);
3191
3192 DESCRIPTION
3193 Define a __start, __stop, .startof. or .sizeof. symbol.
3194 Return the symbol or NULL if no such undefined symbol exists.
3195
3196 .#define bfd_define_start_stop(output_bfd, info, symbol, sec) \
3197 . BFD_SEND (output_bfd, _bfd_define_start_stop, (info, symbol, sec))
3198 .
3199 */
3200
3201 struct bfd_link_hash_entry *
bfd_generic_define_start_stop(struct bfd_link_info * info,const char * symbol,asection * sec)3202 bfd_generic_define_start_stop (struct bfd_link_info *info,
3203 const char *symbol, asection *sec)
3204 {
3205 struct bfd_link_hash_entry *h;
3206
3207 h = bfd_link_hash_lookup (info->hash, symbol, false, false, true);
3208 if (h != NULL
3209 && !h->ldscript_def
3210 && (h->type == bfd_link_hash_undefined
3211 || h->type == bfd_link_hash_undefweak))
3212 {
3213 h->type = bfd_link_hash_defined;
3214 h->u.def.section = sec;
3215 h->u.def.value = 0;
3216 return h;
3217 }
3218 return NULL;
3219 }
3220
3221 /*
3222 FUNCTION
3223 bfd_find_version_for_sym
3224
3225 SYNOPSIS
3226 struct bfd_elf_version_tree * bfd_find_version_for_sym
3227 (struct bfd_elf_version_tree *verdefs,
3228 const char *sym_name, bool *hide);
3229
3230 DESCRIPTION
3231 Search an elf version script tree for symbol versioning
3232 info and export / don't-export status for a given symbol.
3233 Return non-NULL on success and NULL on failure; also sets
3234 the output @samp{hide} boolean parameter.
3235
3236 */
3237
3238 struct bfd_elf_version_tree *
bfd_find_version_for_sym(struct bfd_elf_version_tree * verdefs,const char * sym_name,bool * hide)3239 bfd_find_version_for_sym (struct bfd_elf_version_tree *verdefs,
3240 const char *sym_name,
3241 bool *hide)
3242 {
3243 struct bfd_elf_version_tree *t;
3244 struct bfd_elf_version_tree *local_ver, *global_ver, *exist_ver;
3245 struct bfd_elf_version_tree *star_local_ver, *star_global_ver;
3246
3247 local_ver = NULL;
3248 global_ver = NULL;
3249 star_local_ver = NULL;
3250 star_global_ver = NULL;
3251 exist_ver = NULL;
3252 for (t = verdefs; t != NULL; t = t->next)
3253 {
3254 if (t->globals.list != NULL)
3255 {
3256 struct bfd_elf_version_expr *d = NULL;
3257
3258 while ((d = (*t->match) (&t->globals, d, sym_name)) != NULL)
3259 {
3260 if (d->literal || strcmp (d->pattern, "*") != 0)
3261 global_ver = t;
3262 else
3263 star_global_ver = t;
3264 if (d->symver)
3265 exist_ver = t;
3266 d->script = 1;
3267 /* If the match is a wildcard pattern, keep looking for
3268 a more explicit, perhaps even local, match. */
3269 if (d->literal)
3270 break;
3271 }
3272
3273 if (d != NULL)
3274 break;
3275 }
3276
3277 if (t->locals.list != NULL)
3278 {
3279 struct bfd_elf_version_expr *d = NULL;
3280
3281 while ((d = (*t->match) (&t->locals, d, sym_name)) != NULL)
3282 {
3283 if (d->literal || strcmp (d->pattern, "*") != 0)
3284 local_ver = t;
3285 else
3286 star_local_ver = t;
3287 /* If the match is a wildcard pattern, keep looking for
3288 a more explicit, perhaps even global, match. */
3289 if (d->literal)
3290 {
3291 /* An exact match overrides a global wildcard. */
3292 global_ver = NULL;
3293 star_global_ver = NULL;
3294 break;
3295 }
3296 }
3297
3298 if (d != NULL)
3299 break;
3300 }
3301 }
3302
3303 if (global_ver == NULL && local_ver == NULL)
3304 global_ver = star_global_ver;
3305
3306 if (global_ver != NULL)
3307 {
3308 /* If we already have a versioned symbol that matches the
3309 node for this symbol, then we don't want to create a
3310 duplicate from the unversioned symbol. Instead hide the
3311 unversioned symbol. */
3312 *hide = exist_ver == global_ver;
3313 return global_ver;
3314 }
3315
3316 if (local_ver == NULL)
3317 local_ver = star_local_ver;
3318
3319 if (local_ver != NULL)
3320 {
3321 *hide = true;
3322 return local_ver;
3323 }
3324
3325 return NULL;
3326 }
3327
3328 /*
3329 FUNCTION
3330 bfd_hide_sym_by_version
3331
3332 SYNOPSIS
3333 bool bfd_hide_sym_by_version
3334 (struct bfd_elf_version_tree *verdefs, const char *sym_name);
3335
3336 DESCRIPTION
3337 Search an elf version script tree for symbol versioning
3338 info for a given symbol. Return TRUE if the symbol is hidden.
3339
3340 */
3341
3342 bool
bfd_hide_sym_by_version(struct bfd_elf_version_tree * verdefs,const char * sym_name)3343 bfd_hide_sym_by_version (struct bfd_elf_version_tree *verdefs,
3344 const char *sym_name)
3345 {
3346 bool hidden = false;
3347 bfd_find_version_for_sym (verdefs, sym_name, &hidden);
3348 return hidden;
3349 }
3350
3351 /*
3352 FUNCTION
3353 bfd_link_check_relocs
3354
3355 SYNOPSIS
3356 bool bfd_link_check_relocs
3357 (bfd *abfd, struct bfd_link_info *info);
3358
3359 DESCRIPTION
3360 Checks the relocs in ABFD for validity.
3361 Does not execute the relocs.
3362 Return TRUE if everything is OK, FALSE otherwise.
3363 This is the external entry point to this code.
3364 */
3365
3366 bool
bfd_link_check_relocs(bfd * abfd,struct bfd_link_info * info)3367 bfd_link_check_relocs (bfd *abfd, struct bfd_link_info *info)
3368 {
3369 return BFD_SEND (abfd, _bfd_link_check_relocs, (abfd, info));
3370 }
3371
3372 /*
3373 FUNCTION
3374 _bfd_generic_link_check_relocs
3375
3376 SYNOPSIS
3377 bool _bfd_generic_link_check_relocs
3378 (bfd *abfd, struct bfd_link_info *info);
3379
3380 DESCRIPTION
3381 Stub function for targets that do not implement reloc checking.
3382 Return TRUE.
3383 This is an internal function. It should not be called from
3384 outside the BFD library.
3385 */
3386
3387 bool
_bfd_generic_link_check_relocs(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED)3388 _bfd_generic_link_check_relocs (bfd *abfd ATTRIBUTE_UNUSED,
3389 struct bfd_link_info *info ATTRIBUTE_UNUSED)
3390 {
3391 return true;
3392 }
3393
3394 /*
3395 FUNCTION
3396 bfd_merge_private_bfd_data
3397
3398 SYNOPSIS
3399 bool bfd_merge_private_bfd_data
3400 (bfd *ibfd, struct bfd_link_info *info);
3401
3402 DESCRIPTION
3403 Merge private BFD information from the BFD @var{ibfd} to the
3404 the output file BFD when linking. Return <<TRUE>> on success,
3405 <<FALSE>> on error. Possible error returns are:
3406
3407 o <<bfd_error_no_memory>> -
3408 Not enough memory exists to create private data for @var{obfd}.
3409
3410 .#define bfd_merge_private_bfd_data(ibfd, info) \
3411 . BFD_SEND ((info)->output_bfd, _bfd_merge_private_bfd_data, \
3412 . (ibfd, info))
3413 .
3414 */
3415
3416 /*
3417 INTERNAL_FUNCTION
3418 _bfd_generic_verify_endian_match
3419
3420 SYNOPSIS
3421 bool _bfd_generic_verify_endian_match
3422 (bfd *ibfd, struct bfd_link_info *info);
3423
3424 DESCRIPTION
3425 Can be used from / for bfd_merge_private_bfd_data to check that
3426 endianness matches between input and output file. Returns
3427 TRUE for a match, otherwise returns FALSE and emits an error.
3428 */
3429
3430 bool
_bfd_generic_verify_endian_match(bfd * ibfd,struct bfd_link_info * info)3431 _bfd_generic_verify_endian_match (bfd *ibfd, struct bfd_link_info *info)
3432 {
3433 bfd *obfd = info->output_bfd;
3434
3435 if (ibfd->xvec->byteorder != obfd->xvec->byteorder
3436 && ibfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN
3437 && obfd->xvec->byteorder != BFD_ENDIAN_UNKNOWN)
3438 {
3439 if (bfd_big_endian (ibfd))
3440 _bfd_error_handler (_("%pB: compiled for a big endian system "
3441 "and target is little endian"), ibfd);
3442 else
3443 _bfd_error_handler (_("%pB: compiled for a little endian system "
3444 "and target is big endian"), ibfd);
3445 bfd_set_error (bfd_error_wrong_format);
3446 return false;
3447 }
3448
3449 return true;
3450 }
3451
3452 int
_bfd_nolink_sizeof_headers(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED)3453 _bfd_nolink_sizeof_headers (bfd *abfd ATTRIBUTE_UNUSED,
3454 struct bfd_link_info *info ATTRIBUTE_UNUSED)
3455 {
3456 return 0;
3457 }
3458
3459 bool
_bfd_nolink_bfd_relax_section(bfd * abfd,asection * section ATTRIBUTE_UNUSED,struct bfd_link_info * link_info ATTRIBUTE_UNUSED,bool * again ATTRIBUTE_UNUSED)3460 _bfd_nolink_bfd_relax_section (bfd *abfd,
3461 asection *section ATTRIBUTE_UNUSED,
3462 struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
3463 bool *again ATTRIBUTE_UNUSED)
3464 {
3465 return _bfd_bool_bfd_false_error (abfd);
3466 }
3467
3468 bfd_byte *
_bfd_nolink_bfd_get_relocated_section_contents(bfd * abfd,struct bfd_link_info * link_info ATTRIBUTE_UNUSED,struct bfd_link_order * link_order ATTRIBUTE_UNUSED,bfd_byte * data ATTRIBUTE_UNUSED,bool relocatable ATTRIBUTE_UNUSED,asymbol ** symbols ATTRIBUTE_UNUSED)3469 _bfd_nolink_bfd_get_relocated_section_contents
3470 (bfd *abfd,
3471 struct bfd_link_info *link_info ATTRIBUTE_UNUSED,
3472 struct bfd_link_order *link_order ATTRIBUTE_UNUSED,
3473 bfd_byte *data ATTRIBUTE_UNUSED,
3474 bool relocatable ATTRIBUTE_UNUSED,
3475 asymbol **symbols ATTRIBUTE_UNUSED)
3476 {
3477 return (bfd_byte *) _bfd_ptr_bfd_null_error (abfd);
3478 }
3479
3480 bool
_bfd_nolink_bfd_lookup_section_flags(struct bfd_link_info * info ATTRIBUTE_UNUSED,struct flag_info * flaginfo ATTRIBUTE_UNUSED,asection * section)3481 _bfd_nolink_bfd_lookup_section_flags
3482 (struct bfd_link_info *info ATTRIBUTE_UNUSED,
3483 struct flag_info *flaginfo ATTRIBUTE_UNUSED,
3484 asection *section)
3485 {
3486 return _bfd_bool_bfd_false_error (section->owner);
3487 }
3488
3489 bool
_bfd_nolink_bfd_is_group_section(bfd * abfd,const asection * sec ATTRIBUTE_UNUSED)3490 _bfd_nolink_bfd_is_group_section (bfd *abfd,
3491 const asection *sec ATTRIBUTE_UNUSED)
3492 {
3493 return _bfd_bool_bfd_false_error (abfd);
3494 }
3495
3496 const char *
_bfd_nolink_bfd_group_name(bfd * abfd,const asection * sec ATTRIBUTE_UNUSED)3497 _bfd_nolink_bfd_group_name (bfd *abfd,
3498 const asection *sec ATTRIBUTE_UNUSED)
3499 {
3500 return _bfd_ptr_bfd_null_error (abfd);
3501 }
3502
3503 bool
_bfd_nolink_bfd_discard_group(bfd * abfd,asection * sec ATTRIBUTE_UNUSED)3504 _bfd_nolink_bfd_discard_group (bfd *abfd, asection *sec ATTRIBUTE_UNUSED)
3505 {
3506 return _bfd_bool_bfd_false_error (abfd);
3507 }
3508
3509 struct bfd_link_hash_table *
_bfd_nolink_bfd_link_hash_table_create(bfd * abfd)3510 _bfd_nolink_bfd_link_hash_table_create (bfd *abfd)
3511 {
3512 return (struct bfd_link_hash_table *) _bfd_ptr_bfd_null_error (abfd);
3513 }
3514
3515 void
_bfd_nolink_bfd_link_just_syms(asection * sec ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED)3516 _bfd_nolink_bfd_link_just_syms (asection *sec ATTRIBUTE_UNUSED,
3517 struct bfd_link_info *info ATTRIBUTE_UNUSED)
3518 {
3519 }
3520
3521 void
_bfd_nolink_bfd_copy_link_hash_symbol_type(bfd * abfd ATTRIBUTE_UNUSED,struct bfd_link_hash_entry * from ATTRIBUTE_UNUSED,struct bfd_link_hash_entry * to ATTRIBUTE_UNUSED)3522 _bfd_nolink_bfd_copy_link_hash_symbol_type
3523 (bfd *abfd ATTRIBUTE_UNUSED,
3524 struct bfd_link_hash_entry *from ATTRIBUTE_UNUSED,
3525 struct bfd_link_hash_entry *to ATTRIBUTE_UNUSED)
3526 {
3527 }
3528
3529 bool
_bfd_nolink_bfd_link_split_section(bfd * abfd,asection * sec ATTRIBUTE_UNUSED)3530 _bfd_nolink_bfd_link_split_section (bfd *abfd, asection *sec ATTRIBUTE_UNUSED)
3531 {
3532 return _bfd_bool_bfd_false_error (abfd);
3533 }
3534
3535 bool
_bfd_nolink_section_already_linked(bfd * abfd,asection * sec ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED)3536 _bfd_nolink_section_already_linked (bfd *abfd,
3537 asection *sec ATTRIBUTE_UNUSED,
3538 struct bfd_link_info *info ATTRIBUTE_UNUSED)
3539 {
3540 return _bfd_bool_bfd_false_error (abfd);
3541 }
3542
3543 bool
_bfd_nolink_bfd_define_common_symbol(bfd * abfd,struct bfd_link_info * info ATTRIBUTE_UNUSED,struct bfd_link_hash_entry * h ATTRIBUTE_UNUSED)3544 _bfd_nolink_bfd_define_common_symbol
3545 (bfd *abfd,
3546 struct bfd_link_info *info ATTRIBUTE_UNUSED,
3547 struct bfd_link_hash_entry *h ATTRIBUTE_UNUSED)
3548 {
3549 return _bfd_bool_bfd_false_error (abfd);
3550 }
3551
3552 struct bfd_link_hash_entry *
_bfd_nolink_bfd_define_start_stop(struct bfd_link_info * info ATTRIBUTE_UNUSED,const char * name ATTRIBUTE_UNUSED,asection * sec)3553 _bfd_nolink_bfd_define_start_stop (struct bfd_link_info *info ATTRIBUTE_UNUSED,
3554 const char *name ATTRIBUTE_UNUSED,
3555 asection *sec)
3556 {
3557 return (struct bfd_link_hash_entry *) _bfd_ptr_bfd_null_error (sec->owner);
3558 }
3559
3560 /* Return false if linker should avoid caching relocation infomation
3561 and symbol tables of input files in memory. */
3562
3563 bool
_bfd_link_keep_memory(struct bfd_link_info * info)3564 _bfd_link_keep_memory (struct bfd_link_info * info)
3565 {
3566 bfd *abfd;
3567 bfd_size_type size;
3568
3569 if (!info->keep_memory)
3570 return false;
3571
3572 if (info->max_cache_size == (bfd_size_type) -1)
3573 return true;
3574
3575 abfd = info->input_bfds;
3576 size = info->cache_size;
3577 do
3578 {
3579 if (size >= info->max_cache_size)
3580 {
3581 /* Over the limit. Reduce the memory usage. */
3582 info->keep_memory = false;
3583 return false;
3584 }
3585 if (!abfd)
3586 break;
3587 size += abfd->alloc_size;
3588 abfd = abfd->link.next;
3589 }
3590 while (1);
3591
3592 return true;
3593 }
3594