1 /* linker.c -- BFD linker routines
2 Copyright (C) 1993, 94, 95, 96, 1997 Free Software Foundation, Inc.
3 Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support
5 This file is part of BFD, the Binary File Descriptor library.
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 2 of the License, or
10 (at your option) any later version.
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.
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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
32 The linker uses three special entry points in the BFD target
33 vector. It is not necessary to write special routines for
34 these entry points when creating a new BFD back end, since
35 generic versions are provided. However, writing them can
36 speed up linking and make it use significantly less runtime
39 The first routine creates a hash table used by the other
40 routines. The second routine adds the symbols from an object
41 file to the hash table. The third routine takes all the
42 object files and links them together to create the output
43 file. These routines are designed so that the linker proper
44 does not need to know anything about the symbols in the object
45 files that it is linking. The linker merely arranges the
46 sections as directed by the linker script and lets BFD handle
47 the details of symbols and relocs.
49 The second routine and third routines are passed a pointer to
50 a <<struct bfd_link_info>> structure (defined in
51 <<bfdlink.h>>) which holds information relevant to the link,
52 including the linker hash table (which was created by the
53 first routine) and a set of callback functions to the linker
56 The generic linker routines are in <<linker.c>>, and use the
57 header file <<genlink.h>>. As of this writing, the only back
58 ends which have implemented versions of these routines are
59 a.out (in <<aoutx.h>>) and ECOFF (in <<ecoff.c>>). The a.out
60 routines are used as examples throughout this section.
63 @* Creating a Linker Hash Table::
64 @* Adding Symbols to the Hash Table::
65 @* Performing the Final Link::
69 Creating a Linker Hash Table, Adding Symbols to the Hash Table, Linker Functions, Linker Functions
71 Creating a linker hash table
73 @cindex _bfd_link_hash_table_create in target vector
74 @cindex target vector (_bfd_link_hash_table_create)
75 The linker routines must create a hash table, which must be
76 derived from <<struct bfd_link_hash_table>> described in
77 <<bfdlink.c>>. @xref{Hash Tables} for information on how to
78 create a derived hash table. This entry point is called using
79 the target vector of the linker output file.
81 The <<_bfd_link_hash_table_create>> entry point must allocate
82 and initialize an instance of the desired hash table. If the
83 back end does not require any additional information to be
84 stored with the entries in the hash table, the entry point may
85 simply create a <<struct bfd_link_hash_table>>. Most likely,
86 however, some additional information will be needed.
88 For example, with each entry in the hash table the a.out
89 linker keeps the index the symbol has in the final output file
90 (this index number is used so that when doing a relocateable
91 link the symbol index used in the output file can be quickly
92 filled in when copying over a reloc). The a.out linker code
93 defines the required structures and functions for a hash table
94 derived from <<struct bfd_link_hash_table>>. The a.out linker
95 hash table is created by the function
96 <<NAME(aout,link_hash_table_create)>>; it simply allocates
97 space for the hash table, initializes it, and returns a
100 When writing the linker routines for a new back end, you will
101 generally not know exactly which fields will be required until
102 you have finished. You should simply create a new hash table
103 which defines no additional fields, and then simply add fields
104 as they become necessary.
107 Adding Symbols to the Hash Table, Performing the Final Link, Creating a Linker Hash Table, Linker Functions
109 Adding symbols to the hash table
111 @cindex _bfd_link_add_symbols in target vector
112 @cindex target vector (_bfd_link_add_symbols)
113 The linker proper will call the <<_bfd_link_add_symbols>>
114 entry point for each object file or archive which is to be
115 linked (typically these are the files named on the command
116 line, but some may also come from the linker script). The
117 entry point is responsible for examining the file. For an
118 object file, BFD must add any relevant symbol information to
119 the hash table. For an archive, BFD must determine which
120 elements of the archive should be used and adding them to the
123 The a.out version of this entry point is
124 <<NAME(aout,link_add_symbols)>>.
127 @* Differing file formats::
128 @* Adding symbols from an object file::
129 @* Adding symbols from an archive::
133 Differing file formats, Adding symbols from an object file, Adding Symbols to the Hash Table, Adding Symbols to the Hash Table
135 Differing file formats
137 Normally all the files involved in a link will be of the same
138 format, but it is also possible to link together different
139 format object files, and the back end must support that. The
140 <<_bfd_link_add_symbols>> entry point is called via the target
141 vector of the file to be added. This has an important
142 consequence: the function may not assume that the hash table
143 is the type created by the corresponding
144 <<_bfd_link_hash_table_create>> vector. All the
145 <<_bfd_link_add_symbols>> function can assume about the hash
146 table is that it is derived from <<struct
147 bfd_link_hash_table>>.
149 Sometimes the <<_bfd_link_add_symbols>> function must store
150 some information in the hash table entry to be used by the
151 <<_bfd_final_link>> function. In such a case the <<creator>>
152 field of the hash table must be checked to make sure that the
153 hash table was created by an object file of the same format.
155 The <<_bfd_final_link>> routine must be prepared to handle a
156 hash entry without any extra information added by the
157 <<_bfd_link_add_symbols>> function. A hash entry without
158 extra information will also occur when the linker script
159 directs the linker to create a symbol. Note that, regardless
160 of how a hash table entry is added, all the fields will be
161 initialized to some sort of null value by the hash table entry
162 initialization function.
164 See <<ecoff_link_add_externals>> for an example of how to
165 check the <<creator>> field before saving information (in this
166 case, the ECOFF external symbol debugging information) in a
170 Adding symbols from an object file, Adding symbols from an archive, Differing file formats, Adding Symbols to the Hash Table
172 Adding symbols from an object file
174 When the <<_bfd_link_add_symbols>> routine is passed an object
175 file, it must add all externally visible symbols in that
176 object file to the hash table. The actual work of adding the
177 symbol to the hash table is normally handled by the function
178 <<_bfd_generic_link_add_one_symbol>>. The
179 <<_bfd_link_add_symbols>> routine is responsible for reading
180 all the symbols from the object file and passing the correct
181 information to <<_bfd_generic_link_add_one_symbol>>.
183 The <<_bfd_link_add_symbols>> routine should not use
184 <<bfd_canonicalize_symtab>> to read the symbols. The point of
185 providing this routine is to avoid the overhead of converting
186 the symbols into generic <<asymbol>> structures.
188 @findex _bfd_generic_link_add_one_symbol
189 <<_bfd_generic_link_add_one_symbol>> handles the details of
190 combining common symbols, warning about multiple definitions,
191 and so forth. It takes arguments which describe the symbol to
192 add, notably symbol flags, a section, and an offset. The
193 symbol flags include such things as <<BSF_WEAK>> or
194 <<BSF_INDIRECT>>. The section is a section in the object
195 file, or something like <<bfd_und_section_ptr>> for an undefined
196 symbol or <<bfd_com_section_ptr>> for a common symbol.
198 If the <<_bfd_final_link>> routine is also going to need to
199 read the symbol information, the <<_bfd_link_add_symbols>>
200 routine should save it somewhere attached to the object file
201 BFD. However, the information should only be saved if the
202 <<keep_memory>> field of the <<info>> argument is true, so
203 that the <<-no-keep-memory>> linker switch is effective.
205 The a.out function which adds symbols from an object file is
206 <<aout_link_add_object_symbols>>, and most of the interesting
207 work is in <<aout_link_add_symbols>>. The latter saves
208 pointers to the hash tables entries created by
209 <<_bfd_generic_link_add_one_symbol>> indexed by symbol number,
210 so that the <<_bfd_final_link>> routine does not have to call
211 the hash table lookup routine to locate the entry.
214 Adding symbols from an archive, , Adding symbols from an object file, Adding Symbols to the Hash Table
216 Adding symbols from an archive
218 When the <<_bfd_link_add_symbols>> routine is passed an
219 archive, it must look through the symbols defined by the
220 archive and decide which elements of the archive should be
221 included in the link. For each such element it must call the
222 <<add_archive_element>> linker callback, and it must add the
223 symbols from the object file to the linker hash table.
225 @findex _bfd_generic_link_add_archive_symbols
226 In most cases the work of looking through the symbols in the
227 archive should be done by the
228 <<_bfd_generic_link_add_archive_symbols>> function. This
229 function builds a hash table from the archive symbol table and
230 looks through the list of undefined symbols to see which
231 elements should be included.
232 <<_bfd_generic_link_add_archive_symbols>> is passed a function
233 to call to make the final decision about adding an archive
234 element to the link and to do the actual work of adding the
235 symbols to the linker hash table.
237 The function passed to
238 <<_bfd_generic_link_add_archive_symbols>> must read the
239 symbols of the archive element and decide whether the archive
240 element should be included in the link. If the element is to
241 be included, the <<add_archive_element>> linker callback
242 routine must be called with the element as an argument, and
243 the elements symbols must be added to the linker hash table
244 just as though the element had itself been passed to the
245 <<_bfd_link_add_symbols>> function.
247 When the a.out <<_bfd_link_add_symbols>> function receives an
248 archive, it calls <<_bfd_generic_link_add_archive_symbols>>
249 passing <<aout_link_check_archive_element>> as the function
250 argument. <<aout_link_check_archive_element>> calls
251 <<aout_link_check_ar_symbols>>. If the latter decides to add
252 the element (an element is only added if it provides a real,
253 non-common, definition for a previously undefined or common
254 symbol) it calls the <<add_archive_element>> callback and then
255 <<aout_link_check_archive_element>> calls
256 <<aout_link_add_symbols>> to actually add the symbols to the
259 The ECOFF back end is unusual in that it does not normally
260 call <<_bfd_generic_link_add_archive_symbols>>, because ECOFF
261 archives already contain a hash table of symbols. The ECOFF
262 back end searches the archive itself to avoid the overhead of
263 creating a new hash table.
266 Performing the Final Link, , Adding Symbols to the Hash Table, Linker Functions
268 Performing the final link
270 @cindex _bfd_link_final_link in target vector
271 @cindex target vector (_bfd_final_link)
272 When all the input files have been processed, the linker calls
273 the <<_bfd_final_link>> entry point of the output BFD. This
274 routine is responsible for producing the final output file,
275 which has several aspects. It must relocate the contents of
276 the input sections and copy the data into the output sections.
277 It must build an output symbol table including any local
278 symbols from the input files and the global symbols from the
279 hash table. When producing relocateable output, it must
280 modify the input relocs and write them into the output file.
281 There may also be object format dependent work to be done.
283 The linker will also call the <<write_object_contents>> entry
284 point when the BFD is closed. The two entry points must work
285 together in order to produce the correct output file.
287 The details of how this works are inevitably dependent upon
288 the specific object file format. The a.out
289 <<_bfd_final_link>> routine is <<NAME(aout,final_link)>>.
292 @* Information provided by the linker::
293 @* Relocating the section contents::
294 @* Writing the symbol table::
298 Information provided by the linker, Relocating the section contents, Performing the Final Link, Performing the Final Link
300 Information provided by the linker
302 Before the linker calls the <<_bfd_final_link>> entry point,
303 it sets up some data structures for the function to use.
305 The <<input_bfds>> field of the <<bfd_link_info>> structure
306 will point to a list of all the input files included in the
307 link. These files are linked through the <<link_next>> field
308 of the <<bfd>> structure.
310 Each section in the output file will have a list of
311 <<link_order>> structures attached to the <<link_order_head>>
312 field (the <<link_order>> structure is defined in
313 <<bfdlink.h>>). These structures describe how to create the
314 contents of the output section in terms of the contents of
315 various input sections, fill constants, and, eventually, other
316 types of information. They also describe relocs that must be
317 created by the BFD backend, but do not correspond to any input
318 file; this is used to support -Ur, which builds constructors
319 while generating a relocateable object file.
322 Relocating the section contents, Writing the symbol table, Information provided by the linker, Performing the Final Link
324 Relocating the section contents
326 The <<_bfd_final_link>> function should look through the
327 <<link_order>> structures attached to each section of the
328 output file. Each <<link_order>> structure should either be
329 handled specially, or it should be passed to the function
330 <<_bfd_default_link_order>> which will do the right thing
331 (<<_bfd_default_link_order>> is defined in <<linker.c>>).
333 For efficiency, a <<link_order>> of type
334 <<bfd_indirect_link_order>> whose associated section belongs
335 to a BFD of the same format as the output BFD must be handled
336 specially. This type of <<link_order>> describes part of an
337 output section in terms of a section belonging to one of the
338 input files. The <<_bfd_final_link>> function should read the
339 contents of the section and any associated relocs, apply the
340 relocs to the section contents, and write out the modified
341 section contents. If performing a relocateable link, the
342 relocs themselves must also be modified and written out.
344 @findex _bfd_relocate_contents
345 @findex _bfd_final_link_relocate
346 The functions <<_bfd_relocate_contents>> and
347 <<_bfd_final_link_relocate>> provide some general support for
348 performing the actual relocations, notably overflow checking.
349 Their arguments include information about the symbol the
350 relocation is against and a <<reloc_howto_type>> argument
351 which describes the relocation to perform. These functions
352 are defined in <<reloc.c>>.
354 The a.out function which handles reading, relocating, and
355 writing section contents is <<aout_link_input_section>>. The
356 actual relocation is done in <<aout_link_input_section_std>>
357 and <<aout_link_input_section_ext>>.
360 Writing the symbol table, , Relocating the section contents, Performing the Final Link
362 Writing the symbol table
364 The <<_bfd_final_link>> function must gather all the symbols
365 in the input files and write them out. It must also write out
366 all the symbols in the global hash table. This must be
367 controlled by the <<strip>> and <<discard>> fields of the
368 <<bfd_link_info>> structure.
370 The local symbols of the input files will not have been
371 entered into the linker hash table. The <<_bfd_final_link>>
372 routine must consider each input file and include the symbols
373 in the output file. It may be convenient to do this when
374 looking through the <<link_order>> structures, or it may be
375 done by stepping through the <<input_bfds>> list.
377 The <<_bfd_final_link>> routine must also traverse the global
378 hash table to gather all the externally visible symbols. It
379 is possible that most of the externally visible symbols may be
380 written out when considering the symbols of each input file,
381 but it is still necessary to traverse the hash table since the
382 linker script may have defined some symbols that are not in
383 any of the input files.
385 The <<strip>> field of the <<bfd_link_info>> structure
386 controls which symbols are written out. The possible values
387 are listed in <<bfdlink.h>>. If the value is <<strip_some>>,
388 then the <<keep_hash>> field of the <<bfd_link_info>>
389 structure is a hash table of symbols to keep; each symbol
390 should be looked up in this hash table, and only symbols which
391 are present should be included in the output file.
393 If the <<strip>> field of the <<bfd_link_info>> structure
394 permits local symbols to be written out, the <<discard>> field
395 is used to further controls which local symbols are included
396 in the output file. If the value is <<discard_l>>, then all
397 local symbols which begin with a certain prefix are discarded;
398 this is controlled by the <<bfd_is_local_label_name>> entry point.
400 The a.out backend handles symbols by calling
401 <<aout_link_write_symbols>> on each input BFD and then
402 traversing the global hash table with the function
403 <<aout_link_write_other_symbol>>. It builds a string table
404 while writing out the symbols, which is written to the output
405 file at the end of <<NAME(aout,final_link)>>.
408 static boolean generic_link_read_symbols
410 static boolean generic_link_add_symbols
411 PARAMS ((bfd *, struct bfd_link_info *, boolean collect));
412 static boolean generic_link_add_object_symbols
413 PARAMS ((bfd *, struct bfd_link_info *, boolean collect));
414 static boolean generic_link_check_archive_element_no_collect
415 PARAMS ((bfd *, struct bfd_link_info *, boolean *pneeded));
416 static boolean generic_link_check_archive_element_collect
417 PARAMS ((bfd *, struct bfd_link_info *, boolean *pneeded));
418 static boolean generic_link_check_archive_element
419 PARAMS ((bfd *, struct bfd_link_info *, boolean *pneeded, boolean collect));
420 static boolean generic_link_add_symbol_list
421 PARAMS ((bfd *, struct bfd_link_info *, bfd_size_type count, asymbol **,
423 static bfd *hash_entry_bfd PARAMS ((struct bfd_link_hash_entry *));
424 static void set_symbol_from_hash
425 PARAMS ((asymbol *, struct bfd_link_hash_entry *));
426 static boolean generic_add_output_symbol
427 PARAMS ((bfd *, size_t *psymalloc, asymbol *));
428 static boolean default_fill_link_order
429 PARAMS ((bfd *, struct bfd_link_info *, asection *,
430 struct bfd_link_order *));
431 static boolean default_indirect_link_order
432 PARAMS ((bfd *, struct bfd_link_info *, asection *,
433 struct bfd_link_order *, boolean));
435 /* The link hash table structure is defined in bfdlink.h. It provides
436 a base hash table which the backend specific hash tables are built
439 /* Routine to create an entry in the link hash table. */
441 struct bfd_hash_entry *
442 _bfd_link_hash_newfunc (entry, table, string)
443 struct bfd_hash_entry *entry;
444 struct bfd_hash_table *table;
447 struct bfd_link_hash_entry *ret = (struct bfd_link_hash_entry *) entry;
449 /* Allocate the structure if it has not already been allocated by a
451 if (ret == (struct bfd_link_hash_entry *) NULL)
452 ret = ((struct bfd_link_hash_entry *)
453 bfd_hash_allocate (table, sizeof (struct bfd_link_hash_entry)));
454 if (ret == (struct bfd_link_hash_entry *) NULL)
457 /* Call the allocation method of the superclass. */
458 ret = ((struct bfd_link_hash_entry *)
459 bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string));
463 /* Initialize the local fields. */
464 ret->type = bfd_link_hash_new;
468 return (struct bfd_hash_entry *) ret;
471 /* Initialize a link hash table. The BFD argument is the one
472 responsible for creating this table. */
475 _bfd_link_hash_table_init (table, abfd, newfunc)
476 struct bfd_link_hash_table *table;
478 struct bfd_hash_entry *(*newfunc) PARAMS ((struct bfd_hash_entry *,
479 struct bfd_hash_table *,
482 table->creator = abfd->xvec;
483 table->undefs = NULL;
484 table->undefs_tail = NULL;
485 return bfd_hash_table_init (&table->table, newfunc);
488 /* Look up a symbol in a link hash table. If follow is true, we
489 follow bfd_link_hash_indirect and bfd_link_hash_warning links to
492 struct bfd_link_hash_entry *
493 bfd_link_hash_lookup (table, string, create, copy, follow)
494 struct bfd_link_hash_table *table;
500 struct bfd_link_hash_entry *ret;
502 ret = ((struct bfd_link_hash_entry *)
503 bfd_hash_lookup (&table->table, string, create, copy));
505 if (follow && ret != (struct bfd_link_hash_entry *) NULL)
507 while (ret->type == bfd_link_hash_indirect
508 || ret->type == bfd_link_hash_warning)
515 /* Look up a symbol in the main linker hash table if the symbol might
516 be wrapped. This should only be used for references to an
517 undefined symbol, not for definitions of a symbol. */
519 struct bfd_link_hash_entry *
520 bfd_wrapped_link_hash_lookup (abfd, info, string, create, copy, follow)
522 struct bfd_link_info *info;
528 if (info->wrap_hash != NULL)
533 if (*l == bfd_get_symbol_leading_char (abfd))
537 #define WRAP "__wrap_"
539 if (bfd_hash_lookup (info->wrap_hash, l, false, false) != NULL)
542 struct bfd_link_hash_entry *h;
544 /* This symbol is being wrapped. We want to replace all
545 references to SYM with references to __wrap_SYM. */
547 n = (char *) bfd_malloc (strlen (l) + sizeof WRAP + 1);
551 /* Note that symbol_leading_char may be '\0'. */
552 n[0] = bfd_get_symbol_leading_char (abfd);
556 h = bfd_link_hash_lookup (info->hash, n, create, true, follow);
564 #define REAL "__real_"
567 && strncmp (l, REAL, sizeof REAL - 1) == 0
568 && bfd_hash_lookup (info->wrap_hash, l + sizeof REAL - 1,
569 false, false) != NULL)
572 struct bfd_link_hash_entry *h;
574 /* This is a reference to __real_SYM, where SYM is being
575 wrapped. We want to replace all references to __real_SYM
576 with references to SYM. */
578 n = (char *) bfd_malloc (strlen (l + sizeof REAL - 1) + 2);
582 /* Note that symbol_leading_char may be '\0'. */
583 n[0] = bfd_get_symbol_leading_char (abfd);
585 strcat (n, l + sizeof REAL - 1);
586 h = bfd_link_hash_lookup (info->hash, n, create, true, follow);
594 return bfd_link_hash_lookup (info->hash, string, create, copy, follow);
597 /* Traverse a generic link hash table. The only reason this is not a
598 macro is to do better type checking. This code presumes that an
599 argument passed as a struct bfd_hash_entry * may be caught as a
600 struct bfd_link_hash_entry * with no explicit cast required on the
604 bfd_link_hash_traverse (table, func, info)
605 struct bfd_link_hash_table *table;
606 boolean (*func) PARAMS ((struct bfd_link_hash_entry *, PTR));
609 bfd_hash_traverse (&table->table,
610 ((boolean (*) PARAMS ((struct bfd_hash_entry *, PTR)))
615 /* Add a symbol to the linker hash table undefs list. */
618 bfd_link_add_undef (table, h)
619 struct bfd_link_hash_table *table;
620 struct bfd_link_hash_entry *h;
622 BFD_ASSERT (h->next == NULL);
623 if (table->undefs_tail != (struct bfd_link_hash_entry *) NULL)
624 table->undefs_tail->next = h;
625 if (table->undefs == (struct bfd_link_hash_entry *) NULL)
627 table->undefs_tail = h;
630 /* Routine to create an entry in an generic link hash table. */
632 struct bfd_hash_entry *
633 _bfd_generic_link_hash_newfunc (entry, table, string)
634 struct bfd_hash_entry *entry;
635 struct bfd_hash_table *table;
638 struct generic_link_hash_entry *ret =
639 (struct generic_link_hash_entry *) entry;
641 /* Allocate the structure if it has not already been allocated by a
643 if (ret == (struct generic_link_hash_entry *) NULL)
644 ret = ((struct generic_link_hash_entry *)
645 bfd_hash_allocate (table, sizeof (struct generic_link_hash_entry)));
646 if (ret == (struct generic_link_hash_entry *) NULL)
649 /* Call the allocation method of the superclass. */
650 ret = ((struct generic_link_hash_entry *)
651 _bfd_link_hash_newfunc ((struct bfd_hash_entry *) ret,
656 /* Set local fields. */
657 ret->written = false;
661 return (struct bfd_hash_entry *) ret;
664 /* Create an generic link hash table. */
666 struct bfd_link_hash_table *
667 _bfd_generic_link_hash_table_create (abfd)
670 struct generic_link_hash_table *ret;
672 ret = ((struct generic_link_hash_table *)
673 bfd_alloc (abfd, sizeof (struct generic_link_hash_table)));
675 return (struct bfd_link_hash_table *) NULL;
676 if (! _bfd_link_hash_table_init (&ret->root, abfd,
677 _bfd_generic_link_hash_newfunc))
680 return (struct bfd_link_hash_table *) NULL;
685 /* Grab the symbols for an object file when doing a generic link. We
686 store the symbols in the outsymbols field. We need to keep them
687 around for the entire link to ensure that we only read them once.
688 If we read them multiple times, we might wind up with relocs and
689 the hash table pointing to different instances of the symbol
693 generic_link_read_symbols (abfd)
696 if (abfd->outsymbols == (asymbol **) NULL)
701 symsize = bfd_get_symtab_upper_bound (abfd);
704 abfd->outsymbols = (asymbol **) bfd_alloc (abfd, symsize);
705 if (abfd->outsymbols == NULL && symsize != 0)
707 symcount = bfd_canonicalize_symtab (abfd, abfd->outsymbols);
710 abfd->symcount = symcount;
716 /* Generic function to add symbols to from an object file to the
717 global hash table. This version does not automatically collect
718 constructors by name. */
721 _bfd_generic_link_add_symbols (abfd, info)
723 struct bfd_link_info *info;
725 return generic_link_add_symbols (abfd, info, false);
728 /* Generic function to add symbols from an object file to the global
729 hash table. This version automatically collects constructors by
730 name, as the collect2 program does. It should be used for any
731 target which does not provide some other mechanism for setting up
732 constructors and destructors; these are approximately those targets
733 for which gcc uses collect2 and do not support stabs. */
736 _bfd_generic_link_add_symbols_collect (abfd, info)
738 struct bfd_link_info *info;
740 return generic_link_add_symbols (abfd, info, true);
743 /* Add symbols from an object file to the global hash table. */
746 generic_link_add_symbols (abfd, info, collect)
748 struct bfd_link_info *info;
753 switch (bfd_get_format (abfd))
756 ret = generic_link_add_object_symbols (abfd, info, collect);
759 ret = (_bfd_generic_link_add_archive_symbols
762 ? generic_link_check_archive_element_collect
763 : generic_link_check_archive_element_no_collect)));
766 bfd_set_error (bfd_error_wrong_format);
773 /* Add symbols from an object file to the global hash table. */
776 generic_link_add_object_symbols (abfd, info, collect)
778 struct bfd_link_info *info;
781 if (! generic_link_read_symbols (abfd))
783 return generic_link_add_symbol_list (abfd, info,
784 _bfd_generic_link_get_symcount (abfd),
785 _bfd_generic_link_get_symbols (abfd),
789 /* We build a hash table of all symbols defined in an archive. */
791 /* An archive symbol may be defined by multiple archive elements.
792 This linked list is used to hold the elements. */
796 struct archive_list *next;
800 /* An entry in an archive hash table. */
802 struct archive_hash_entry
804 struct bfd_hash_entry root;
805 /* Where the symbol is defined. */
806 struct archive_list *defs;
809 /* An archive hash table itself. */
811 struct archive_hash_table
813 struct bfd_hash_table table;
816 static struct bfd_hash_entry *archive_hash_newfunc
817 PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *));
818 static boolean archive_hash_table_init
819 PARAMS ((struct archive_hash_table *,
820 struct bfd_hash_entry *(*) (struct bfd_hash_entry *,
821 struct bfd_hash_table *,
824 /* Create a new entry for an archive hash table. */
826 static struct bfd_hash_entry *
827 archive_hash_newfunc (entry, table, string)
828 struct bfd_hash_entry *entry;
829 struct bfd_hash_table *table;
832 struct archive_hash_entry *ret = (struct archive_hash_entry *) entry;
834 /* Allocate the structure if it has not already been allocated by a
836 if (ret == (struct archive_hash_entry *) NULL)
837 ret = ((struct archive_hash_entry *)
838 bfd_hash_allocate (table, sizeof (struct archive_hash_entry)));
839 if (ret == (struct archive_hash_entry *) NULL)
842 /* Call the allocation method of the superclass. */
843 ret = ((struct archive_hash_entry *)
844 bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string));
848 /* Initialize the local fields. */
849 ret->defs = (struct archive_list *) NULL;
852 return (struct bfd_hash_entry *) ret;
855 /* Initialize an archive hash table. */
858 archive_hash_table_init (table, newfunc)
859 struct archive_hash_table *table;
860 struct bfd_hash_entry *(*newfunc) PARAMS ((struct bfd_hash_entry *,
861 struct bfd_hash_table *,
864 return bfd_hash_table_init (&table->table, newfunc);
867 /* Look up an entry in an archive hash table. */
869 #define archive_hash_lookup(t, string, create, copy) \
870 ((struct archive_hash_entry *) \
871 bfd_hash_lookup (&(t)->table, (string), (create), (copy)))
873 /* Allocate space in an archive hash table. */
875 #define archive_hash_allocate(t, size) bfd_hash_allocate (&(t)->table, (size))
877 /* Free an archive hash table. */
879 #define archive_hash_table_free(t) bfd_hash_table_free (&(t)->table)
881 /* Generic function to add symbols from an archive file to the global
882 hash file. This function presumes that the archive symbol table
883 has already been read in (this is normally done by the
884 bfd_check_format entry point). It looks through the undefined and
885 common symbols and searches the archive symbol table for them. If
886 it finds an entry, it includes the associated object file in the
889 The old linker looked through the archive symbol table for
890 undefined symbols. We do it the other way around, looking through
891 undefined symbols for symbols defined in the archive. The
892 advantage of the newer scheme is that we only have to look through
893 the list of undefined symbols once, whereas the old method had to
894 re-search the symbol table each time a new object file was added.
896 The CHECKFN argument is used to see if an object file should be
897 included. CHECKFN should set *PNEEDED to true if the object file
898 should be included, and must also call the bfd_link_info
899 add_archive_element callback function and handle adding the symbols
900 to the global hash table. CHECKFN should only return false if some
901 sort of error occurs.
903 For some formats, such as a.out, it is possible to look through an
904 object file but not actually include it in the link. The
905 archive_pass field in a BFD is used to avoid checking the symbols
906 of an object files too many times. When an object is included in
907 the link, archive_pass is set to -1. If an object is scanned but
908 not included, archive_pass is set to the pass number. The pass
909 number is incremented each time a new object file is included. The
910 pass number is used because when a new object file is included it
911 may create new undefined symbols which cause a previously examined
912 object file to be included. */
915 _bfd_generic_link_add_archive_symbols (abfd, info, checkfn)
917 struct bfd_link_info *info;
918 boolean (*checkfn) PARAMS ((bfd *, struct bfd_link_info *,
923 register carsym *arsym;
925 struct archive_hash_table arsym_hash;
927 struct bfd_link_hash_entry **pundef;
929 if (! bfd_has_map (abfd))
931 /* An empty archive is a special case. */
932 if (bfd_openr_next_archived_file (abfd, (bfd *) NULL) == NULL)
934 bfd_set_error (bfd_error_no_armap);
938 arsyms = bfd_ardata (abfd)->symdefs;
939 arsym_end = arsyms + bfd_ardata (abfd)->symdef_count;
941 /* In order to quickly determine whether an symbol is defined in
942 this archive, we build a hash table of the symbols. */
943 if (! archive_hash_table_init (&arsym_hash, archive_hash_newfunc))
945 for (arsym = arsyms, indx = 0; arsym < arsym_end; arsym++, indx++)
947 struct archive_hash_entry *arh;
948 struct archive_list *l, **pp;
950 arh = archive_hash_lookup (&arsym_hash, arsym->name, true, false);
951 if (arh == (struct archive_hash_entry *) NULL)
953 l = ((struct archive_list *)
954 archive_hash_allocate (&arsym_hash, sizeof (struct archive_list)));
958 for (pp = &arh->defs;
959 *pp != (struct archive_list *) NULL;
966 /* The archive_pass field in the archive itself is used to
967 initialize PASS, sine we may search the same archive multiple
969 pass = abfd->archive_pass + 1;
971 /* New undefined symbols are added to the end of the list, so we
972 only need to look through it once. */
973 pundef = &info->hash->undefs;
974 while (*pundef != (struct bfd_link_hash_entry *) NULL)
976 struct bfd_link_hash_entry *h;
977 struct archive_hash_entry *arh;
978 struct archive_list *l;
982 /* When a symbol is defined, it is not necessarily removed from
984 if (h->type != bfd_link_hash_undefined
985 && h->type != bfd_link_hash_common)
987 /* Remove this entry from the list, for general cleanliness
988 and because we are going to look through the list again
989 if we search any more libraries. We can't remove the
990 entry if it is the tail, because that would lose any
991 entries we add to the list later on (it would also cause
992 us to lose track of whether the symbol has been
994 if (*pundef != info->hash->undefs_tail)
995 *pundef = (*pundef)->next;
997 pundef = &(*pundef)->next;
1001 /* Look for this symbol in the archive symbol map. */
1002 arh = archive_hash_lookup (&arsym_hash, h->root.string, false, false);
1003 if (arh == (struct archive_hash_entry *) NULL)
1005 pundef = &(*pundef)->next;
1009 /* Look at all the objects which define this symbol. */
1010 for (l = arh->defs; l != (struct archive_list *) NULL; l = l->next)
1015 /* If the symbol has gotten defined along the way, quit. */
1016 if (h->type != bfd_link_hash_undefined
1017 && h->type != bfd_link_hash_common)
1020 element = bfd_get_elt_at_index (abfd, l->indx);
1021 if (element == (bfd *) NULL)
1024 /* If we've already included this element, or if we've
1025 already checked it on this pass, continue. */
1026 if (element->archive_pass == -1
1027 || element->archive_pass == pass)
1030 /* If we can't figure this element out, just ignore it. */
1031 if (! bfd_check_format (element, bfd_object))
1033 element->archive_pass = -1;
1037 /* CHECKFN will see if this element should be included, and
1038 go ahead and include it if appropriate. */
1039 if (! (*checkfn) (element, info, &needed))
1043 element->archive_pass = pass;
1046 element->archive_pass = -1;
1048 /* Increment the pass count to show that we may need to
1049 recheck object files which were already checked. */
1054 pundef = &(*pundef)->next;
1057 archive_hash_table_free (&arsym_hash);
1059 /* Save PASS in case we are called again. */
1060 abfd->archive_pass = pass;
1065 archive_hash_table_free (&arsym_hash);
1069 /* See if we should include an archive element. This version is used
1070 when we do not want to automatically collect constructors based on
1071 the symbol name, presumably because we have some other mechanism
1072 for finding them. */
1075 generic_link_check_archive_element_no_collect (abfd, info, pneeded)
1077 struct bfd_link_info *info;
1080 return generic_link_check_archive_element (abfd, info, pneeded, false);
1083 /* See if we should include an archive element. This version is used
1084 when we want to automatically collect constructors based on the
1085 symbol name, as collect2 does. */
1088 generic_link_check_archive_element_collect (abfd, info, pneeded)
1090 struct bfd_link_info *info;
1093 return generic_link_check_archive_element (abfd, info, pneeded, true);
1096 /* See if we should include an archive element. Optionally collect
1100 generic_link_check_archive_element (abfd, info, pneeded, collect)
1102 struct bfd_link_info *info;
1106 asymbol **pp, **ppend;
1110 if (! generic_link_read_symbols (abfd))
1113 pp = _bfd_generic_link_get_symbols (abfd);
1114 ppend = pp + _bfd_generic_link_get_symcount (abfd);
1115 for (; pp < ppend; pp++)
1118 struct bfd_link_hash_entry *h;
1122 /* We are only interested in globally visible symbols. */
1123 if (! bfd_is_com_section (p->section)
1124 && (p->flags & (BSF_GLOBAL | BSF_INDIRECT | BSF_WEAK)) == 0)
1127 /* We are only interested if we know something about this
1128 symbol, and it is undefined or common. An undefined weak
1129 symbol (type bfd_link_hash_undefweak) is not considered to be
1130 a reference when pulling files out of an archive. See the
1131 SVR4 ABI, p. 4-27. */
1132 h = bfd_link_hash_lookup (info->hash, bfd_asymbol_name (p), false,
1134 if (h == (struct bfd_link_hash_entry *) NULL
1135 || (h->type != bfd_link_hash_undefined
1136 && h->type != bfd_link_hash_common))
1139 /* P is a symbol we are looking for. */
1141 if (! bfd_is_com_section (p->section))
1143 bfd_size_type symcount;
1146 /* This object file defines this symbol, so pull it in. */
1147 if (! (*info->callbacks->add_archive_element) (info, abfd,
1148 bfd_asymbol_name (p)))
1150 symcount = _bfd_generic_link_get_symcount (abfd);
1151 symbols = _bfd_generic_link_get_symbols (abfd);
1152 if (! generic_link_add_symbol_list (abfd, info, symcount,
1159 /* P is a common symbol. */
1161 if (h->type == bfd_link_hash_undefined)
1167 symbfd = h->u.undef.abfd;
1168 if (symbfd == (bfd *) NULL)
1170 /* This symbol was created as undefined from outside
1171 BFD. We assume that we should link in the object
1172 file. This is for the -u option in the linker. */
1173 if (! (*info->callbacks->add_archive_element)
1174 (info, abfd, bfd_asymbol_name (p)))
1180 /* Turn the symbol into a common symbol but do not link in
1181 the object file. This is how a.out works. Object
1182 formats that require different semantics must implement
1183 this function differently. This symbol is already on the
1184 undefs list. We add the section to a common section
1185 attached to symbfd to ensure that it is in a BFD which
1186 will be linked in. */
1187 h->type = bfd_link_hash_common;
1189 ((struct bfd_link_hash_common_entry *)
1190 bfd_hash_allocate (&info->hash->table,
1191 sizeof (struct bfd_link_hash_common_entry)));
1192 if (h->u.c.p == NULL)
1195 size = bfd_asymbol_value (p);
1198 power = bfd_log2 (size);
1201 h->u.c.p->alignment_power = power;
1203 if (p->section == bfd_com_section_ptr)
1204 h->u.c.p->section = bfd_make_section_old_way (symbfd, "COMMON");
1206 h->u.c.p->section = bfd_make_section_old_way (symbfd,
1208 h->u.c.p->section->flags = SEC_ALLOC;
1212 /* Adjust the size of the common symbol if necessary. This
1213 is how a.out works. Object formats that require
1214 different semantics must implement this function
1216 if (bfd_asymbol_value (p) > h->u.c.size)
1217 h->u.c.size = bfd_asymbol_value (p);
1221 /* This archive element is not needed. */
1225 /* Add the symbols from an object file to the global hash table. ABFD
1226 is the object file. INFO is the linker information. SYMBOL_COUNT
1227 is the number of symbols. SYMBOLS is the list of symbols. COLLECT
1228 is true if constructors should be automatically collected by name
1229 as is done by collect2. */
1232 generic_link_add_symbol_list (abfd, info, symbol_count, symbols, collect)
1234 struct bfd_link_info *info;
1235 bfd_size_type symbol_count;
1239 asymbol **pp, **ppend;
1242 ppend = symbols + symbol_count;
1243 for (; pp < ppend; pp++)
1249 if ((p->flags & (BSF_INDIRECT
1254 || bfd_is_und_section (bfd_get_section (p))
1255 || bfd_is_com_section (bfd_get_section (p))
1256 || bfd_is_ind_section (bfd_get_section (p)))
1260 struct generic_link_hash_entry *h;
1262 name = bfd_asymbol_name (p);
1263 if (((p->flags & BSF_INDIRECT) != 0
1264 || bfd_is_ind_section (p->section))
1268 string = bfd_asymbol_name (*pp);
1270 else if ((p->flags & BSF_WARNING) != 0
1273 /* The name of P is actually the warning string, and the
1274 next symbol is the one to warn about. */
1277 name = bfd_asymbol_name (*pp);
1283 if (! (_bfd_generic_link_add_one_symbol
1284 (info, abfd, name, p->flags, bfd_get_section (p),
1285 p->value, string, false, collect,
1286 (struct bfd_link_hash_entry **) &h)))
1289 /* If this is a constructor symbol, and the linker didn't do
1290 anything with it, then we want to just pass the symbol
1291 through to the output file. This will happen when
1293 if ((p->flags & BSF_CONSTRUCTOR) != 0
1294 && (h == NULL || h->root.type == bfd_link_hash_new))
1300 /* Save the BFD symbol so that we don't lose any backend
1301 specific information that may be attached to it. We only
1302 want this one if it gives more information than the
1303 existing one; we don't want to replace a defined symbol
1304 with an undefined one. This routine may be called with a
1305 hash table other than the generic hash table, so we only
1306 do this if we are certain that the hash table is a
1308 if (info->hash->creator == abfd->xvec)
1310 if (h->sym == (asymbol *) NULL
1311 || (! bfd_is_und_section (bfd_get_section (p))
1312 && (! bfd_is_com_section (bfd_get_section (p))
1313 || bfd_is_und_section (bfd_get_section (h->sym)))))
1316 /* BSF_OLD_COMMON is a hack to support COFF reloc
1317 reading, and it should go away when the COFF
1318 linker is switched to the new version. */
1319 if (bfd_is_com_section (bfd_get_section (p)))
1320 p->flags |= BSF_OLD_COMMON;
1324 /* Store a back pointer from the symbol to the hash
1325 table entry for the benefit of relaxation code until
1326 it gets rewritten to not use asymbol structures.
1327 Setting this is also used to check whether these
1328 symbols were set up by the generic linker. */
1329 p->udata.p = (PTR) h;
1336 /* We use a state table to deal with adding symbols from an object
1337 file. The first index into the state table describes the symbol
1338 from the object file. The second index into the state table is the
1339 type of the symbol in the hash table. */
1341 /* The symbol from the object file is turned into one of these row
1346 UNDEF_ROW, /* Undefined. */
1347 UNDEFW_ROW, /* Weak undefined. */
1348 DEF_ROW, /* Defined. */
1349 DEFW_ROW, /* Weak defined. */
1350 COMMON_ROW, /* Common. */
1351 INDR_ROW, /* Indirect. */
1352 WARN_ROW, /* Warning. */
1353 SET_ROW /* Member of set. */
1356 /* apparently needed for Hitachi 3050R(HI-UX/WE2)? */
1359 /* The actions to take in the state table. */
1364 UND, /* Mark symbol undefined. */
1365 WEAK, /* Mark symbol weak undefined. */
1366 DEF, /* Mark symbol defined. */
1367 DEFW, /* Mark symbol weak defined. */
1368 COM, /* Mark symbol common. */
1369 REF, /* Mark defined symbol referenced. */
1370 CREF, /* Possibly warn about common reference to defined symbol. */
1371 CDEF, /* Define existing common symbol. */
1372 NOACT, /* No action. */
1373 BIG, /* Mark symbol common using largest size. */
1374 MDEF, /* Multiple definition error. */
1375 MIND, /* Multiple indirect symbols. */
1376 IND, /* Make indirect symbol. */
1377 CIND, /* Make indirect symbol from existing common symbol. */
1378 SET, /* Add value to set. */
1379 MWARN, /* Make warning symbol. */
1380 WARN, /* Issue warning. */
1381 CWARN, /* Warn if referenced, else MWARN. */
1382 CYCLE, /* Repeat with symbol pointed to. */
1383 REFC, /* Mark indirect symbol referenced and then CYCLE. */
1384 WARNC /* Issue warning and then CYCLE. */
1387 /* The state table itself. The first index is a link_row and the
1388 second index is a bfd_link_hash_type. */
1390 static const enum link_action link_action[8][8] =
1392 /* current\prev new undef undefw def defw com indr warn */
1393 /* UNDEF_ROW */ {UND, NOACT, UND, REF, REF, NOACT, REFC, WARNC },
1394 /* UNDEFW_ROW */ {WEAK, NOACT, NOACT, REF, REF, NOACT, REFC, WARNC },
1395 /* DEF_ROW */ {DEF, DEF, DEF, MDEF, DEF, CDEF, MDEF, CYCLE },
1396 /* DEFW_ROW */ {DEFW, DEFW, DEFW, NOACT, NOACT, NOACT, NOACT, CYCLE },
1397 /* COMMON_ROW */ {COM, COM, COM, CREF, CREF, BIG, REFC, WARNC },
1398 /* INDR_ROW */ {IND, IND, IND, MDEF, IND, CIND, MIND, CYCLE },
1399 /* WARN_ROW */ {MWARN, WARN, WARN, CWARN, CWARN, WARN, CWARN, MWARN },
1400 /* SET_ROW */ {SET, SET, SET, SET, SET, SET, CYCLE, CYCLE }
1403 /* Most of the entries in the LINK_ACTION table are straightforward,
1404 but a few are somewhat subtle.
1406 A reference to an indirect symbol (UNDEF_ROW/indr or
1407 UNDEFW_ROW/indr) is counted as a reference both to the indirect
1408 symbol and to the symbol the indirect symbol points to.
1410 A reference to a warning symbol (UNDEF_ROW/warn or UNDEFW_ROW/warn)
1411 causes the warning to be issued.
1413 A common definition of an indirect symbol (COMMON_ROW/indr) is
1414 treated as a multiple definition error. Likewise for an indirect
1415 definition of a common symbol (INDR_ROW/com).
1417 An indirect definition of a warning (INDR_ROW/warn) does not cause
1418 the warning to be issued.
1420 If a warning is created for an indirect symbol (WARN_ROW/indr) no
1421 warning is created for the symbol the indirect symbol points to.
1423 Adding an entry to a set does not count as a reference to a set,
1424 and no warning is issued (SET_ROW/warn). */
1426 /* Return the BFD in which a hash entry has been defined, if known. */
1430 struct bfd_link_hash_entry *h;
1432 while (h->type == bfd_link_hash_warning)
1438 case bfd_link_hash_undefined:
1439 case bfd_link_hash_undefweak:
1440 return h->u.undef.abfd;
1441 case bfd_link_hash_defined:
1442 case bfd_link_hash_defweak:
1443 return h->u.def.section->owner;
1444 case bfd_link_hash_common:
1445 return h->u.c.p->section->owner;
1450 /* Add a symbol to the global hash table.
1451 ABFD is the BFD the symbol comes from.
1452 NAME is the name of the symbol.
1453 FLAGS is the BSF_* bits associated with the symbol.
1454 SECTION is the section in which the symbol is defined; this may be
1455 bfd_und_section_ptr or bfd_com_section_ptr.
1456 VALUE is the value of the symbol, relative to the section.
1457 STRING is used for either an indirect symbol, in which case it is
1458 the name of the symbol to indirect to, or a warning symbol, in
1459 which case it is the warning string.
1460 COPY is true if NAME or STRING must be copied into locally
1461 allocated memory if they need to be saved.
1462 COLLECT is true if we should automatically collect gcc constructor
1463 or destructor names as collect2 does.
1464 HASHP, if not NULL, is a place to store the created hash table
1465 entry; if *HASHP is not NULL, the caller has already looked up
1466 the hash table entry, and stored it in *HASHP. */
1469 _bfd_generic_link_add_one_symbol (info, abfd, name, flags, section, value,
1470 string, copy, collect, hashp)
1471 struct bfd_link_info *info;
1480 struct bfd_link_hash_entry **hashp;
1483 struct bfd_link_hash_entry *h;
1486 if (bfd_is_ind_section (section)
1487 || (flags & BSF_INDIRECT) != 0)
1489 else if ((flags & BSF_WARNING) != 0)
1491 else if ((flags & BSF_CONSTRUCTOR) != 0)
1493 else if (bfd_is_und_section (section))
1495 if ((flags & BSF_WEAK) != 0)
1500 else if ((flags & BSF_WEAK) != 0)
1502 else if (bfd_is_com_section (section))
1507 if (hashp != NULL && *hashp != NULL)
1511 if (row == UNDEF_ROW || row == UNDEFW_ROW)
1512 h = bfd_wrapped_link_hash_lookup (abfd, info, name, true, copy, false);
1514 h = bfd_link_hash_lookup (info->hash, name, true, copy, false);
1523 if (info->notice_all
1524 || (info->notice_hash != (struct bfd_hash_table *) NULL
1525 && (bfd_hash_lookup (info->notice_hash, name, false, false)
1526 != (struct bfd_hash_entry *) NULL)))
1528 if (! (*info->callbacks->notice) (info, h->root.string, abfd, section,
1533 if (hashp != (struct bfd_link_hash_entry **) NULL)
1538 enum link_action action;
1541 action = link_action[(int) row][(int) h->type];
1552 /* Make a new undefined symbol. */
1553 h->type = bfd_link_hash_undefined;
1554 h->u.undef.abfd = abfd;
1555 bfd_link_add_undef (info->hash, h);
1559 /* Make a new weak undefined symbol. */
1560 h->type = bfd_link_hash_undefweak;
1561 h->u.undef.abfd = abfd;
1565 /* We have found a definition for a symbol which was
1566 previously common. */
1567 BFD_ASSERT (h->type == bfd_link_hash_common);
1568 if (! ((*info->callbacks->multiple_common)
1569 (info, h->root.string,
1570 h->u.c.p->section->owner, bfd_link_hash_common, h->u.c.size,
1571 abfd, bfd_link_hash_defined, (bfd_vma) 0)))
1577 enum bfd_link_hash_type oldtype;
1579 /* Define a symbol. */
1582 h->type = bfd_link_hash_defweak;
1584 h->type = bfd_link_hash_defined;
1585 h->u.def.section = section;
1586 h->u.def.value = value;
1588 /* If we have been asked to, we act like collect2 and
1589 identify all functions that might be global
1590 constructors and destructors and pass them up in a
1591 callback. We only do this for certain object file
1592 types, since many object file types can handle this
1594 if (collect && name[0] == '_')
1598 /* A constructor or destructor name starts like this:
1599 _+GLOBAL_[_.$][ID][_.$] where the first [_.$] and
1600 the second are the same character (we accept any
1601 character there, in case a new object file format
1602 comes along with even worse naming restrictions). */
1604 #define CONS_PREFIX "GLOBAL_"
1605 #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1)
1611 && strncmp (s, CONS_PREFIX, CONS_PREFIX_LEN - 1) == 0)
1615 c = s[CONS_PREFIX_LEN + 1];
1616 if ((c == 'I' || c == 'D')
1617 && s[CONS_PREFIX_LEN] == s[CONS_PREFIX_LEN + 2])
1619 /* If this is a definition of a symbol which
1620 was previously weakly defined, we are in
1621 trouble. We have already added a
1622 constructor entry for the weak defined
1623 symbol, and now we are trying to add one
1624 for the new symbol. Fortunately, this case
1625 should never arise in practice. */
1626 if (oldtype == bfd_link_hash_defweak)
1629 if (! ((*info->callbacks->constructor)
1631 c == 'I' ? true : false,
1632 h->root.string, abfd, section, value)))
1642 /* We have found a common definition for a symbol. */
1643 if (h->type == bfd_link_hash_new)
1644 bfd_link_add_undef (info->hash, h);
1645 h->type = bfd_link_hash_common;
1647 ((struct bfd_link_hash_common_entry *)
1648 bfd_hash_allocate (&info->hash->table,
1649 sizeof (struct bfd_link_hash_common_entry)));
1650 if (h->u.c.p == NULL)
1653 h->u.c.size = value;
1655 /* Select a default alignment based on the size. This may
1656 be overridden by the caller. */
1660 power = bfd_log2 (value);
1663 h->u.c.p->alignment_power = power;
1666 /* The section of a common symbol is only used if the common
1667 symbol is actually allocated. It basically provides a
1668 hook for the linker script to decide which output section
1669 the common symbols should be put in. In most cases, the
1670 section of a common symbol will be bfd_com_section_ptr,
1671 the code here will choose a common symbol section named
1672 "COMMON", and the linker script will contain *(COMMON) in
1673 the appropriate place. A few targets use separate common
1674 sections for small symbols, and they require special
1676 if (section == bfd_com_section_ptr)
1678 h->u.c.p->section = bfd_make_section_old_way (abfd, "COMMON");
1679 h->u.c.p->section->flags = SEC_ALLOC;
1681 else if (section->owner != abfd)
1683 h->u.c.p->section = bfd_make_section_old_way (abfd,
1685 h->u.c.p->section->flags = SEC_ALLOC;
1688 h->u.c.p->section = section;
1692 /* A reference to a defined symbol. */
1693 if (h->next == NULL && info->hash->undefs_tail != h)
1698 /* We have found a common definition for a symbol which
1699 already had a common definition. Use the maximum of the
1701 BFD_ASSERT (h->type == bfd_link_hash_common);
1702 if (! ((*info->callbacks->multiple_common)
1703 (info, h->root.string,
1704 h->u.c.p->section->owner, bfd_link_hash_common, h->u.c.size,
1705 abfd, bfd_link_hash_common, value)))
1707 if (value > h->u.c.size)
1711 h->u.c.size = value;
1713 /* Select a default alignment based on the size. This may
1714 be overridden by the caller. */
1715 power = bfd_log2 (value);
1718 h->u.c.p->alignment_power = power;
1726 /* We have found a common definition for a symbol which
1727 was already defined. FIXME: It would nice if we could
1728 report the BFD which defined an indirect symbol, but we
1729 don't have anywhere to store the information. */
1730 if (h->type == bfd_link_hash_defined
1731 || h->type == bfd_link_hash_defweak)
1732 obfd = h->u.def.section->owner;
1735 if (! ((*info->callbacks->multiple_common)
1736 (info, h->root.string, obfd, h->type, (bfd_vma) 0,
1737 abfd, bfd_link_hash_common, value)))
1743 /* Multiple indirect symbols. This is OK if they both point
1744 to the same symbol. */
1745 if (strcmp (h->u.i.link->root.string, string) == 0)
1749 /* Handle a multiple definition. */
1756 case bfd_link_hash_defined:
1757 msec = h->u.def.section;
1758 mval = h->u.def.value;
1760 case bfd_link_hash_indirect:
1761 msec = bfd_ind_section_ptr;
1768 /* Ignore a redefinition of an absolute symbol to the same
1769 value; it's harmless. */
1770 if (h->type == bfd_link_hash_defined
1771 && bfd_is_abs_section (msec)
1772 && bfd_is_abs_section (section)
1776 if (! ((*info->callbacks->multiple_definition)
1777 (info, h->root.string, msec->owner, msec, mval, abfd,
1784 /* Create an indirect symbol from an existing common symbol. */
1785 BFD_ASSERT (h->type == bfd_link_hash_common);
1786 if (! ((*info->callbacks->multiple_common)
1787 (info, h->root.string,
1788 h->u.c.p->section->owner, bfd_link_hash_common, h->u.c.size,
1789 abfd, bfd_link_hash_indirect, (bfd_vma) 0)))
1793 /* Create an indirect symbol. */
1795 struct bfd_link_hash_entry *inh;
1797 /* STRING is the name of the symbol we want to indirect
1799 inh = bfd_wrapped_link_hash_lookup (abfd, info, string, true,
1801 if (inh == (struct bfd_link_hash_entry *) NULL)
1803 if (inh->type == bfd_link_hash_new)
1805 inh->type = bfd_link_hash_undefined;
1806 inh->u.undef.abfd = abfd;
1807 bfd_link_add_undef (info->hash, inh);
1810 /* If the indirect symbol has been referenced, we need to
1811 push the reference down to the symbol we are
1813 if (h->type != bfd_link_hash_new)
1819 h->type = bfd_link_hash_indirect;
1825 /* Add an entry to a set. */
1826 if (! (*info->callbacks->add_to_set) (info, h, BFD_RELOC_CTOR,
1827 abfd, section, value))
1832 /* Issue a warning and cycle. */
1833 if (h->u.i.warning != NULL)
1835 if (! (*info->callbacks->warning) (info, h->u.i.warning,
1836 h->root.string, abfd,
1840 /* Only issue a warning once. */
1841 h->u.i.warning = NULL;
1845 /* Try again with the referenced symbol. */
1851 /* A reference to an indirect symbol. */
1852 if (h->next == NULL && info->hash->undefs_tail != h)
1859 /* Issue a warning. */
1860 if (! (*info->callbacks->warning) (info, string, h->root.string,
1862 (asection *) NULL, (bfd_vma) 0))
1867 /* Warn if this symbol has been referenced already,
1868 otherwise add a warning. A symbol has been referenced if
1869 the next field is not NULL, or it is the tail of the
1870 undefined symbol list. The REF case above helps to
1872 if (h->next != NULL || info->hash->undefs_tail == h)
1874 if (! (*info->callbacks->warning) (info, string, h->root.string,
1883 /* Make a warning symbol. */
1885 struct bfd_link_hash_entry *sub;
1887 /* STRING is the warning to give. */
1888 sub = ((struct bfd_link_hash_entry *)
1889 ((*info->hash->table.newfunc)
1890 ((struct bfd_hash_entry *) NULL, &info->hash->table,
1895 sub->type = bfd_link_hash_warning;
1898 sub->u.i.warning = string;
1903 w = bfd_hash_allocate (&info->hash->table,
1904 strlen (string) + 1);
1908 sub->u.i.warning = w;
1911 bfd_hash_replace (&info->hash->table,
1912 (struct bfd_hash_entry *) h,
1913 (struct bfd_hash_entry *) sub);
1925 /* Generic final link routine. */
1928 _bfd_generic_final_link (abfd, info)
1930 struct bfd_link_info *info;
1934 struct bfd_link_order *p;
1936 struct generic_write_global_symbol_info wginfo;
1938 abfd->outsymbols = (asymbol **) NULL;
1942 /* Mark all sections which will be included in the output file. */
1943 for (o = abfd->sections; o != NULL; o = o->next)
1944 for (p = o->link_order_head; p != NULL; p = p->next)
1945 if (p->type == bfd_indirect_link_order)
1946 p->u.indirect.section->linker_mark = true;
1948 /* Build the output symbol table. */
1949 for (sub = info->input_bfds; sub != (bfd *) NULL; sub = sub->link_next)
1950 if (! _bfd_generic_link_output_symbols (abfd, sub, info, &outsymalloc))
1953 /* Accumulate the global symbols. */
1955 wginfo.output_bfd = abfd;
1956 wginfo.psymalloc = &outsymalloc;
1957 _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info),
1958 _bfd_generic_link_write_global_symbol,
1961 if (info->relocateable)
1963 /* Allocate space for the output relocs for each section. */
1964 for (o = abfd->sections;
1965 o != (asection *) NULL;
1969 for (p = o->link_order_head;
1970 p != (struct bfd_link_order *) NULL;
1973 if (p->type == bfd_section_reloc_link_order
1974 || p->type == bfd_symbol_reloc_link_order)
1976 else if (p->type == bfd_indirect_link_order)
1978 asection *input_section;
1985 input_section = p->u.indirect.section;
1986 input_bfd = input_section->owner;
1987 relsize = bfd_get_reloc_upper_bound (input_bfd,
1991 relocs = (arelent **) bfd_malloc ((size_t) relsize);
1992 if (!relocs && relsize != 0)
1994 symbols = _bfd_generic_link_get_symbols (input_bfd);
1995 reloc_count = bfd_canonicalize_reloc (input_bfd,
1999 if (reloc_count < 0)
2001 BFD_ASSERT ((unsigned long) reloc_count
2002 == input_section->reloc_count);
2003 o->reloc_count += reloc_count;
2007 if (o->reloc_count > 0)
2009 o->orelocation = ((arelent **)
2012 * sizeof (arelent *))));
2013 if (!o->orelocation)
2015 o->flags |= SEC_RELOC;
2016 /* Reset the count so that it can be used as an index
2017 when putting in the output relocs. */
2023 /* Handle all the link order information for the sections. */
2024 for (o = abfd->sections;
2025 o != (asection *) NULL;
2028 for (p = o->link_order_head;
2029 p != (struct bfd_link_order *) NULL;
2034 case bfd_section_reloc_link_order:
2035 case bfd_symbol_reloc_link_order:
2036 if (! _bfd_generic_reloc_link_order (abfd, info, o, p))
2039 case bfd_indirect_link_order:
2040 if (! default_indirect_link_order (abfd, info, o, p, true))
2044 if (! _bfd_default_link_order (abfd, info, o, p))
2054 /* Add an output symbol to the output BFD. */
2057 generic_add_output_symbol (output_bfd, psymalloc, sym)
2062 if (output_bfd->symcount >= *psymalloc)
2066 if (*psymalloc == 0)
2070 newsyms = (asymbol **) bfd_realloc (output_bfd->outsymbols,
2071 *psymalloc * sizeof (asymbol *));
2072 if (newsyms == (asymbol **) NULL)
2074 output_bfd->outsymbols = newsyms;
2077 output_bfd->outsymbols[output_bfd->symcount] = sym;
2078 ++output_bfd->symcount;
2083 /* Handle the symbols for an input BFD. */
2086 _bfd_generic_link_output_symbols (output_bfd, input_bfd, info, psymalloc)
2089 struct bfd_link_info *info;
2095 if (! generic_link_read_symbols (input_bfd))
2098 /* Create a filename symbol if we are supposed to. */
2099 if (info->create_object_symbols_section != (asection *) NULL)
2103 for (sec = input_bfd->sections;
2104 sec != (asection *) NULL;
2107 if (sec->output_section == info->create_object_symbols_section)
2111 newsym = bfd_make_empty_symbol (input_bfd);
2114 newsym->name = input_bfd->filename;
2116 newsym->flags = BSF_LOCAL | BSF_FILE;
2117 newsym->section = sec;
2119 if (! generic_add_output_symbol (output_bfd, psymalloc,
2128 /* Adjust the values of the globally visible symbols, and write out
2130 sym_ptr = _bfd_generic_link_get_symbols (input_bfd);
2131 sym_end = sym_ptr + _bfd_generic_link_get_symcount (input_bfd);
2132 for (; sym_ptr < sym_end; sym_ptr++)
2135 struct generic_link_hash_entry *h;
2138 h = (struct generic_link_hash_entry *) NULL;
2140 if ((sym->flags & (BSF_INDIRECT
2145 || bfd_is_und_section (bfd_get_section (sym))
2146 || bfd_is_com_section (bfd_get_section (sym))
2147 || bfd_is_ind_section (bfd_get_section (sym)))
2149 if (sym->udata.p != NULL)
2150 h = (struct generic_link_hash_entry *) sym->udata.p;
2151 else if ((sym->flags & BSF_CONSTRUCTOR) != 0)
2153 /* This case normally means that the main linker code
2154 deliberately ignored this constructor symbol. We
2155 should just pass it through. This will screw up if
2156 the constructor symbol is from a different,
2157 non-generic, object file format, but the case will
2158 only arise when linking with -r, which will probably
2159 fail anyhow, since there will be no way to represent
2160 the relocs in the output format being used. */
2163 else if (bfd_is_und_section (bfd_get_section (sym)))
2164 h = ((struct generic_link_hash_entry *)
2165 bfd_wrapped_link_hash_lookup (output_bfd, info,
2166 bfd_asymbol_name (sym),
2167 false, false, true));
2169 h = _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info),
2170 bfd_asymbol_name (sym),
2171 false, false, true);
2173 if (h != (struct generic_link_hash_entry *) NULL)
2175 /* Force all references to this symbol to point to
2176 the same area in memory. It is possible that
2177 this routine will be called with a hash table
2178 other than a generic hash table, so we double
2180 if (info->hash->creator == input_bfd->xvec)
2182 if (h->sym != (asymbol *) NULL)
2183 *sym_ptr = sym = h->sym;
2186 switch (h->root.type)
2189 case bfd_link_hash_new:
2191 case bfd_link_hash_undefined:
2193 case bfd_link_hash_undefweak:
2194 sym->flags |= BSF_WEAK;
2196 case bfd_link_hash_indirect:
2197 h = (struct generic_link_hash_entry *) h->root.u.i.link;
2199 case bfd_link_hash_defined:
2200 sym->flags |= BSF_GLOBAL;
2201 sym->flags &=~ BSF_CONSTRUCTOR;
2202 sym->value = h->root.u.def.value;
2203 sym->section = h->root.u.def.section;
2205 case bfd_link_hash_defweak:
2206 sym->flags |= BSF_WEAK;
2207 sym->flags &=~ BSF_CONSTRUCTOR;
2208 sym->value = h->root.u.def.value;
2209 sym->section = h->root.u.def.section;
2211 case bfd_link_hash_common:
2212 sym->value = h->root.u.c.size;
2213 sym->flags |= BSF_GLOBAL;
2214 if (! bfd_is_com_section (sym->section))
2216 BFD_ASSERT (bfd_is_und_section (sym->section));
2217 sym->section = bfd_com_section_ptr;
2219 /* We do not set the section of the symbol to
2220 h->root.u.c.p->section. That value was saved so
2221 that we would know where to allocate the symbol
2222 if it was defined. In this case the type is
2223 still bfd_link_hash_common, so we did not define
2224 it, so we do not want to use that section. */
2230 /* This switch is straight from the old code in
2231 write_file_locals in ldsym.c. */
2232 if (info->strip == strip_all
2233 || (info->strip == strip_some
2234 && (bfd_hash_lookup (info->keep_hash, bfd_asymbol_name (sym),
2236 == (struct bfd_hash_entry *) NULL)))
2238 else if ((sym->flags & (BSF_GLOBAL | BSF_WEAK)) != 0)
2240 /* If this symbol is marked as occurring now, rather
2241 than at the end, output it now. This is used for
2242 COFF C_EXT FCN symbols. FIXME: There must be a
2244 if (bfd_asymbol_bfd (sym) == input_bfd
2245 && (sym->flags & BSF_NOT_AT_END) != 0)
2250 else if (bfd_is_ind_section (sym->section))
2252 else if ((sym->flags & BSF_DEBUGGING) != 0)
2254 if (info->strip == strip_none)
2259 else if (bfd_is_und_section (sym->section)
2260 || bfd_is_com_section (sym->section))
2262 else if ((sym->flags & BSF_LOCAL) != 0)
2264 if ((sym->flags & BSF_WARNING) != 0)
2268 switch (info->discard)
2275 if (bfd_is_local_label (input_bfd, sym))
2286 else if ((sym->flags & BSF_CONSTRUCTOR))
2288 if (info->strip != strip_all)
2296 /* If this symbol is in a section which is not being included
2297 in the output file, then we don't want to output the symbol.
2299 Gross. .bss and similar sections won't have the linker_mark
2301 if ((sym->section->flags & SEC_HAS_CONTENTS) != 0
2302 && sym->section->linker_mark == false)
2307 if (! generic_add_output_symbol (output_bfd, psymalloc, sym))
2309 if (h != (struct generic_link_hash_entry *) NULL)
2317 /* Set the section and value of a generic BFD symbol based on a linker
2318 hash table entry. */
2321 set_symbol_from_hash (sym, h)
2323 struct bfd_link_hash_entry *h;
2330 case bfd_link_hash_new:
2331 /* This can happen when a constructor symbol is seen but we are
2332 not building constructors. */
2333 if (sym->section != NULL)
2335 BFD_ASSERT ((sym->flags & BSF_CONSTRUCTOR) != 0);
2339 sym->flags |= BSF_CONSTRUCTOR;
2340 sym->section = bfd_abs_section_ptr;
2344 case bfd_link_hash_undefined:
2345 sym->section = bfd_und_section_ptr;
2348 case bfd_link_hash_undefweak:
2349 sym->section = bfd_und_section_ptr;
2351 sym->flags |= BSF_WEAK;
2353 case bfd_link_hash_defined:
2354 sym->section = h->u.def.section;
2355 sym->value = h->u.def.value;
2357 case bfd_link_hash_defweak:
2358 sym->flags |= BSF_WEAK;
2359 sym->section = h->u.def.section;
2360 sym->value = h->u.def.value;
2362 case bfd_link_hash_common:
2363 sym->value = h->u.c.size;
2364 if (sym->section == NULL)
2365 sym->section = bfd_com_section_ptr;
2366 else if (! bfd_is_com_section (sym->section))
2368 BFD_ASSERT (bfd_is_und_section (sym->section));
2369 sym->section = bfd_com_section_ptr;
2371 /* Do not set the section; see _bfd_generic_link_output_symbols. */
2373 case bfd_link_hash_indirect:
2374 case bfd_link_hash_warning:
2375 /* FIXME: What should we do here? */
2380 /* Write out a global symbol, if it hasn't already been written out.
2381 This is called for each symbol in the hash table. */
2384 _bfd_generic_link_write_global_symbol (h, data)
2385 struct generic_link_hash_entry *h;
2388 struct generic_write_global_symbol_info *wginfo =
2389 (struct generic_write_global_symbol_info *) data;
2397 if (wginfo->info->strip == strip_all
2398 || (wginfo->info->strip == strip_some
2399 && bfd_hash_lookup (wginfo->info->keep_hash, h->root.root.string,
2400 false, false) == NULL))
2403 if (h->sym != (asymbol *) NULL)
2407 sym = bfd_make_empty_symbol (wginfo->output_bfd);
2410 sym->name = h->root.root.string;
2414 set_symbol_from_hash (sym, &h->root);
2416 sym->flags |= BSF_GLOBAL;
2418 if (! generic_add_output_symbol (wginfo->output_bfd, wginfo->psymalloc,
2421 /* FIXME: No way to return failure. */
2428 /* Create a relocation. */
2431 _bfd_generic_reloc_link_order (abfd, info, sec, link_order)
2433 struct bfd_link_info *info;
2435 struct bfd_link_order *link_order;
2439 if (! info->relocateable)
2441 if (sec->orelocation == (arelent **) NULL)
2444 r = (arelent *) bfd_alloc (abfd, sizeof (arelent));
2445 if (r == (arelent *) NULL)
2448 r->address = link_order->offset;
2449 r->howto = bfd_reloc_type_lookup (abfd, link_order->u.reloc.p->reloc);
2452 bfd_set_error (bfd_error_bad_value);
2456 /* Get the symbol to use for the relocation. */
2457 if (link_order->type == bfd_section_reloc_link_order)
2458 r->sym_ptr_ptr = link_order->u.reloc.p->u.section->symbol_ptr_ptr;
2461 struct generic_link_hash_entry *h;
2463 h = ((struct generic_link_hash_entry *)
2464 bfd_wrapped_link_hash_lookup (abfd, info,
2465 link_order->u.reloc.p->u.name,
2466 false, false, true));
2467 if (h == (struct generic_link_hash_entry *) NULL
2470 if (! ((*info->callbacks->unattached_reloc)
2471 (info, link_order->u.reloc.p->u.name,
2472 (bfd *) NULL, (asection *) NULL, (bfd_vma) 0)))
2474 bfd_set_error (bfd_error_bad_value);
2477 r->sym_ptr_ptr = &h->sym;
2480 /* If this is an inplace reloc, write the addend to the object file.
2481 Otherwise, store it in the reloc addend. */
2482 if (! r->howto->partial_inplace)
2483 r->addend = link_order->u.reloc.p->addend;
2487 bfd_reloc_status_type rstat;
2491 size = bfd_get_reloc_size (r->howto);
2492 buf = (bfd_byte *) bfd_zmalloc (size);
2493 if (buf == (bfd_byte *) NULL)
2495 rstat = _bfd_relocate_contents (r->howto, abfd,
2496 link_order->u.reloc.p->addend, buf);
2502 case bfd_reloc_outofrange:
2504 case bfd_reloc_overflow:
2505 if (! ((*info->callbacks->reloc_overflow)
2507 (link_order->type == bfd_section_reloc_link_order
2508 ? bfd_section_name (abfd, link_order->u.reloc.p->u.section)
2509 : link_order->u.reloc.p->u.name),
2510 r->howto->name, link_order->u.reloc.p->addend,
2511 (bfd *) NULL, (asection *) NULL, (bfd_vma) 0)))
2518 ok = bfd_set_section_contents (abfd, sec, (PTR) buf,
2519 (file_ptr) link_order->offset, size);
2527 sec->orelocation[sec->reloc_count] = r;
2533 /* Allocate a new link_order for a section. */
2535 struct bfd_link_order *
2536 bfd_new_link_order (abfd, section)
2540 struct bfd_link_order *new;
2542 new = ((struct bfd_link_order *)
2543 bfd_alloc (abfd, sizeof (struct bfd_link_order)));
2547 new->type = bfd_undefined_link_order;
2550 new->next = (struct bfd_link_order *) NULL;
2552 if (section->link_order_tail != (struct bfd_link_order *) NULL)
2553 section->link_order_tail->next = new;
2555 section->link_order_head = new;
2556 section->link_order_tail = new;
2561 /* Default link order processing routine. Note that we can not handle
2562 the reloc_link_order types here, since they depend upon the details
2563 of how the particular backends generates relocs. */
2566 _bfd_default_link_order (abfd, info, sec, link_order)
2568 struct bfd_link_info *info;
2570 struct bfd_link_order *link_order;
2572 switch (link_order->type)
2574 case bfd_undefined_link_order:
2575 case bfd_section_reloc_link_order:
2576 case bfd_symbol_reloc_link_order:
2579 case bfd_indirect_link_order:
2580 return default_indirect_link_order (abfd, info, sec, link_order,
2582 case bfd_fill_link_order:
2583 return default_fill_link_order (abfd, info, sec, link_order);
2584 case bfd_data_link_order:
2585 return bfd_set_section_contents (abfd, sec,
2586 (PTR) link_order->u.data.contents,
2587 (file_ptr) link_order->offset,
2592 /* Default routine to handle a bfd_fill_link_order. */
2596 default_fill_link_order (abfd, info, sec, link_order)
2598 struct bfd_link_info *info;
2600 struct bfd_link_order *link_order;
2608 BFD_ASSERT ((sec->flags & SEC_HAS_CONTENTS) != 0);
2610 size = (size_t) link_order->size;
2611 space = (char *) bfd_malloc (size);
2612 if (space == NULL && size != 0)
2615 fill = link_order->u.fill.value;
2616 for (i = 0; i < size; i += 2)
2617 space[i] = fill >> 8;
2618 for (i = 1; i < size; i += 2)
2620 result = bfd_set_section_contents (abfd, sec, space,
2621 (file_ptr) link_order->offset,
2627 /* Default routine to handle a bfd_indirect_link_order. */
2630 default_indirect_link_order (output_bfd, info, output_section, link_order,
2633 struct bfd_link_info *info;
2634 asection *output_section;
2635 struct bfd_link_order *link_order;
2636 boolean generic_linker;
2638 asection *input_section;
2640 bfd_byte *contents = NULL;
2641 bfd_byte *new_contents;
2643 BFD_ASSERT ((output_section->flags & SEC_HAS_CONTENTS) != 0);
2645 if (link_order->size == 0)
2648 input_section = link_order->u.indirect.section;
2649 input_bfd = input_section->owner;
2651 BFD_ASSERT (input_section->output_section == output_section);
2652 BFD_ASSERT (input_section->output_offset == link_order->offset);
2653 BFD_ASSERT (input_section->_cooked_size == link_order->size);
2655 if (info->relocateable
2656 && input_section->reloc_count > 0
2657 && output_section->orelocation == (arelent **) NULL)
2659 /* Space has not been allocated for the output relocations.
2660 This can happen when we are called by a specific backend
2661 because somebody is attempting to link together different
2662 types of object files. Handling this case correctly is
2663 difficult, and sometimes impossible. */
2664 (*_bfd_error_handler)
2665 ("Attempt to do relocateable link with %s input and %s output",
2666 bfd_get_target (input_bfd), bfd_get_target (output_bfd));
2667 bfd_set_error (bfd_error_wrong_format);
2671 if (! generic_linker)
2676 /* Get the canonical symbols. The generic linker will always
2677 have retrieved them by this point, but we are being called by
2678 a specific linker, presumably because we are linking
2679 different types of object files together. */
2680 if (! generic_link_read_symbols (input_bfd))
2683 /* Since we have been called by a specific linker, rather than
2684 the generic linker, the values of the symbols will not be
2685 right. They will be the values as seen in the input file,
2686 not the values of the final link. We need to fix them up
2687 before we can relocate the section. */
2688 sympp = _bfd_generic_link_get_symbols (input_bfd);
2689 symppend = sympp + _bfd_generic_link_get_symcount (input_bfd);
2690 for (; sympp < symppend; sympp++)
2693 struct bfd_link_hash_entry *h;
2697 if ((sym->flags & (BSF_INDIRECT
2702 || bfd_is_und_section (bfd_get_section (sym))
2703 || bfd_is_com_section (bfd_get_section (sym))
2704 || bfd_is_ind_section (bfd_get_section (sym)))
2706 /* sym->udata may have been set by
2707 generic_link_add_symbol_list. */
2708 if (sym->udata.p != NULL)
2709 h = (struct bfd_link_hash_entry *) sym->udata.p;
2710 else if (bfd_is_und_section (bfd_get_section (sym)))
2711 h = bfd_wrapped_link_hash_lookup (output_bfd, info,
2712 bfd_asymbol_name (sym),
2713 false, false, true);
2715 h = bfd_link_hash_lookup (info->hash,
2716 bfd_asymbol_name (sym),
2717 false, false, true);
2719 set_symbol_from_hash (sym, h);
2724 /* Get and relocate the section contents. */
2725 contents = ((bfd_byte *)
2726 bfd_malloc (bfd_section_size (input_bfd, input_section)));
2727 if (contents == NULL && bfd_section_size (input_bfd, input_section) != 0)
2729 new_contents = (bfd_get_relocated_section_contents
2730 (output_bfd, info, link_order, contents, info->relocateable,
2731 _bfd_generic_link_get_symbols (input_bfd)));
2735 /* Output the section contents. */
2736 if (! bfd_set_section_contents (output_bfd, output_section,
2738 link_order->offset, link_order->size))
2741 if (contents != NULL)
2746 if (contents != NULL)
2751 /* A little routine to count the number of relocs in a link_order
2755 _bfd_count_link_order_relocs (link_order)
2756 struct bfd_link_order *link_order;
2758 register unsigned int c;
2759 register struct bfd_link_order *l;
2762 for (l = link_order; l != (struct bfd_link_order *) NULL; l = l->next)
2764 if (l->type == bfd_section_reloc_link_order
2765 || l->type == bfd_symbol_reloc_link_order)
2774 bfd_link_split_section
2777 boolean bfd_link_split_section(bfd *abfd, asection *sec);
2780 Return nonzero if @var{sec} should be split during a
2781 reloceatable or final link.
2783 .#define bfd_link_split_section(abfd, sec) \
2784 . BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec))
2792 _bfd_generic_link_split_section (abfd, sec)