1 /* linker.c -- BFD linker routines
2 Copyright (C) 1993-2014 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 3 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., 51 Franklin Street - Fifth Floor, Boston,
20 MA 02110-1301, USA. */
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
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.
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
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.
64 @* Creating a Linker Hash Table::
65 @* Adding Symbols to the Hash Table::
66 @* Performing the Final Link::
70 Creating a Linker Hash Table, Adding Symbols to the Hash Table, Linker Functions, Linker Functions
72 Creating a linker hash table
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.
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.
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
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.
108 Adding Symbols to the Hash Table, Performing the Final Link, Creating a Linker Hash Table, Linker Functions
110 Adding symbols to the hash table
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
124 The a.out version of this entry point is
125 <<NAME(aout,link_add_symbols)>>.
128 @* Differing file formats::
129 @* Adding symbols from an object file::
130 @* Adding symbols from an archive::
134 Differing file formats, Adding symbols from an object file, Adding Symbols to the Hash Table, Adding Symbols to the Hash Table
136 Differing file formats
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>>.
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.
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.
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
171 Adding symbols from an object file, Adding symbols from an archive, Differing file formats, Adding Symbols to the Hash Table
173 Adding symbols from an object file
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>>.
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.
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.
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.
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.
215 Adding symbols from an archive, , Adding symbols from an object file, Adding Symbols to the Hash Table
217 Adding symbols from an archive
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.)
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. This
233 function builds a hash table from the archive symbol table and
234 looks through the list of undefined symbols to see which
235 elements should be included.
236 <<_bfd_generic_link_add_archive_symbols>> is passed a function
237 to call to make the final decision about adding an archive
238 element to the link and to do the actual work of adding the
239 symbols to the linker hash table.
241 The function passed to
242 <<_bfd_generic_link_add_archive_symbols>> must read the
243 symbols of the archive element and decide whether the archive
244 element should be included in the link. If the element is to
245 be included, the <<add_archive_element>> linker callback
246 routine must be called with the element as an argument, and
247 the element's symbols must be added to the linker hash table
248 just as though the element had itself been passed to the
249 <<_bfd_link_add_symbols>> function. The <<add_archive_element>>
250 callback has the option to indicate that it would like to
251 replace the element archive with a substitute BFD, in which
252 case it is the symbols of that substitute BFD that must be
253 added to the linker hash table instead.
255 When the a.out <<_bfd_link_add_symbols>> function receives an
256 archive, it calls <<_bfd_generic_link_add_archive_symbols>>
257 passing <<aout_link_check_archive_element>> as the function
258 argument. <<aout_link_check_archive_element>> calls
259 <<aout_link_check_ar_symbols>>. If the latter decides to add
260 the element (an element is only added if it provides a real,
261 non-common, definition for a previously undefined or common
262 symbol) it calls the <<add_archive_element>> callback and then
263 <<aout_link_check_archive_element>> calls
264 <<aout_link_add_symbols>> to actually add the symbols to the
265 linker hash table - possibly those of a substitute BFD, if the
266 <<add_archive_element>> callback avails itself of that option.
268 The ECOFF back end is unusual in that it does not normally
269 call <<_bfd_generic_link_add_archive_symbols>>, because ECOFF
270 archives already contain a hash table of symbols. The ECOFF
271 back end searches the archive itself to avoid the overhead of
272 creating a new hash table.
275 Performing the Final Link, , Adding Symbols to the Hash Table, Linker Functions
277 Performing the final link
279 @cindex _bfd_link_final_link in target vector
280 @cindex target vector (_bfd_final_link)
281 When all the input files have been processed, the linker calls
282 the <<_bfd_final_link>> entry point of the output BFD. This
283 routine is responsible for producing the final output file,
284 which has several aspects. It must relocate the contents of
285 the input sections and copy the data into the output sections.
286 It must build an output symbol table including any local
287 symbols from the input files and the global symbols from the
288 hash table. When producing relocatable output, it must
289 modify the input relocs and write them into the output file.
290 There may also be object format dependent work to be done.
292 The linker will also call the <<write_object_contents>> entry
293 point when the BFD is closed. The two entry points must work
294 together in order to produce the correct output file.
296 The details of how this works are inevitably dependent upon
297 the specific object file format. The a.out
298 <<_bfd_final_link>> routine is <<NAME(aout,final_link)>>.
301 @* Information provided by the linker::
302 @* Relocating the section contents::
303 @* Writing the symbol table::
307 Information provided by the linker, Relocating the section contents, Performing the Final Link, Performing the Final Link
309 Information provided by the linker
311 Before the linker calls the <<_bfd_final_link>> entry point,
312 it sets up some data structures for the function to use.
314 The <<input_bfds>> field of the <<bfd_link_info>> structure
315 will point to a list of all the input files included in the
316 link. These files are linked through the <<link_next>> field
317 of the <<bfd>> structure.
319 Each section in the output file will have a list of
320 <<link_order>> structures attached to the <<map_head.link_order>>
321 field (the <<link_order>> structure is defined in
322 <<bfdlink.h>>). These structures describe how to create the
323 contents of the output section in terms of the contents of
324 various input sections, fill constants, and, eventually, other
325 types of information. They also describe relocs that must be
326 created by the BFD backend, but do not correspond to any input
327 file; this is used to support -Ur, which builds constructors
328 while generating a relocatable object file.
331 Relocating the section contents, Writing the symbol table, Information provided by the linker, Performing the Final Link
333 Relocating the section contents
335 The <<_bfd_final_link>> function should look through the
336 <<link_order>> structures attached to each section of the
337 output file. Each <<link_order>> structure should either be
338 handled specially, or it should be passed to the function
339 <<_bfd_default_link_order>> which will do the right thing
340 (<<_bfd_default_link_order>> is defined in <<linker.c>>).
342 For efficiency, a <<link_order>> of type
343 <<bfd_indirect_link_order>> whose associated section belongs
344 to a BFD of the same format as the output BFD must be handled
345 specially. This type of <<link_order>> describes part of an
346 output section in terms of a section belonging to one of the
347 input files. The <<_bfd_final_link>> function should read the
348 contents of the section and any associated relocs, apply the
349 relocs to the section contents, and write out the modified
350 section contents. If performing a relocatable link, the
351 relocs themselves must also be modified and written out.
353 @findex _bfd_relocate_contents
354 @findex _bfd_final_link_relocate
355 The functions <<_bfd_relocate_contents>> and
356 <<_bfd_final_link_relocate>> provide some general support for
357 performing the actual relocations, notably overflow checking.
358 Their arguments include information about the symbol the
359 relocation is against and a <<reloc_howto_type>> argument
360 which describes the relocation to perform. These functions
361 are defined in <<reloc.c>>.
363 The a.out function which handles reading, relocating, and
364 writing section contents is <<aout_link_input_section>>. The
365 actual relocation is done in <<aout_link_input_section_std>>
366 and <<aout_link_input_section_ext>>.
369 Writing the symbol table, , Relocating the section contents, Performing the Final Link
371 Writing the symbol table
373 The <<_bfd_final_link>> function must gather all the symbols
374 in the input files and write them out. It must also write out
375 all the symbols in the global hash table. This must be
376 controlled by the <<strip>> and <<discard>> fields of the
377 <<bfd_link_info>> structure.
379 The local symbols of the input files will not have been
380 entered into the linker hash table. The <<_bfd_final_link>>
381 routine must consider each input file and include the symbols
382 in the output file. It may be convenient to do this when
383 looking through the <<link_order>> structures, or it may be
384 done by stepping through the <<input_bfds>> list.
386 The <<_bfd_final_link>> routine must also traverse the global
387 hash table to gather all the externally visible symbols. It
388 is possible that most of the externally visible symbols may be
389 written out when considering the symbols of each input file,
390 but it is still necessary to traverse the hash table since the
391 linker script may have defined some symbols that are not in
392 any of the input files.
394 The <<strip>> field of the <<bfd_link_info>> structure
395 controls which symbols are written out. The possible values
396 are listed in <<bfdlink.h>>. If the value is <<strip_some>>,
397 then the <<keep_hash>> field of the <<bfd_link_info>>
398 structure is a hash table of symbols to keep; each symbol
399 should be looked up in this hash table, and only symbols which
400 are present should be included in the output file.
402 If the <<strip>> field of the <<bfd_link_info>> structure
403 permits local symbols to be written out, the <<discard>> field
404 is used to further controls which local symbols are included
405 in the output file. If the value is <<discard_l>>, then all
406 local symbols which begin with a certain prefix are discarded;
407 this is controlled by the <<bfd_is_local_label_name>> entry point.
409 The a.out backend handles symbols by calling
410 <<aout_link_write_symbols>> on each input BFD and then
411 traversing the global hash table with the function
412 <<aout_link_write_other_symbol>>. It builds a string table
413 while writing out the symbols, which is written to the output
414 file at the end of <<NAME(aout,final_link)>>.
417 static bfd_boolean generic_link_add_object_symbols
418 (bfd
*, struct bfd_link_info
*, bfd_boolean collect
);
419 static bfd_boolean generic_link_add_symbols
420 (bfd
*, struct bfd_link_info
*, bfd_boolean
);
421 static bfd_boolean generic_link_check_archive_element_no_collect
422 (bfd
*, struct bfd_link_info
*, bfd_boolean
*);
423 static bfd_boolean generic_link_check_archive_element_collect
424 (bfd
*, struct bfd_link_info
*, bfd_boolean
*);
425 static bfd_boolean generic_link_check_archive_element
426 (bfd
*, struct bfd_link_info
*, bfd_boolean
*, bfd_boolean
);
427 static bfd_boolean generic_link_add_symbol_list
428 (bfd
*, struct bfd_link_info
*, bfd_size_type count
, asymbol
**,
430 static bfd_boolean generic_add_output_symbol
431 (bfd
*, size_t *psymalloc
, asymbol
*);
432 static bfd_boolean default_data_link_order
433 (bfd
*, struct bfd_link_info
*, asection
*, struct bfd_link_order
*);
434 static bfd_boolean default_indirect_link_order
435 (bfd
*, struct bfd_link_info
*, asection
*, struct bfd_link_order
*,
438 /* The link hash table structure is defined in bfdlink.h. It provides
439 a base hash table which the backend specific hash tables are built
442 /* Routine to create an entry in the link hash table. */
444 struct bfd_hash_entry
*
445 _bfd_link_hash_newfunc (struct bfd_hash_entry
*entry
,
446 struct bfd_hash_table
*table
,
449 /* Allocate the structure if it has not already been allocated by a
453 entry
= (struct bfd_hash_entry
*)
454 bfd_hash_allocate (table
, sizeof (struct bfd_link_hash_entry
));
459 /* Call the allocation method of the superclass. */
460 entry
= bfd_hash_newfunc (entry
, table
, string
);
463 struct bfd_link_hash_entry
*h
= (struct bfd_link_hash_entry
*) entry
;
465 /* Initialize the local fields. */
466 memset ((char *) &h
->root
+ sizeof (h
->root
), 0,
467 sizeof (*h
) - sizeof (h
->root
));
473 /* Initialize a link hash table. The BFD argument is the one
474 responsible for creating this table. */
477 _bfd_link_hash_table_init
478 (struct bfd_link_hash_table
*table
,
479 bfd
*abfd ATTRIBUTE_UNUSED
,
480 struct bfd_hash_entry
*(*newfunc
) (struct bfd_hash_entry
*,
481 struct bfd_hash_table
*,
483 unsigned int entsize
)
485 table
->undefs
= NULL
;
486 table
->undefs_tail
= NULL
;
487 table
->type
= bfd_link_generic_hash_table
;
489 return bfd_hash_table_init (&table
->table
, newfunc
, entsize
);
492 /* Look up a symbol in a link hash table. If follow is TRUE, we
493 follow bfd_link_hash_indirect and bfd_link_hash_warning links to
496 struct bfd_link_hash_entry
*
497 bfd_link_hash_lookup (struct bfd_link_hash_table
*table
,
503 struct bfd_link_hash_entry
*ret
;
505 ret
= ((struct bfd_link_hash_entry
*)
506 bfd_hash_lookup (&table
->table
, string
, create
, copy
));
508 if (follow
&& ret
!= NULL
)
510 while (ret
->type
== bfd_link_hash_indirect
511 || ret
->type
== bfd_link_hash_warning
)
518 /* Look up a symbol in the main linker hash table if the symbol might
519 be wrapped. This should only be used for references to an
520 undefined symbol, not for definitions of a symbol. */
522 struct bfd_link_hash_entry
*
523 bfd_wrapped_link_hash_lookup (bfd
*abfd
,
524 struct bfd_link_info
*info
,
532 if (info
->wrap_hash
!= NULL
)
538 if (*l
== bfd_get_symbol_leading_char (abfd
) || *l
== info
->wrap_char
)
545 #define WRAP "__wrap_"
547 if (bfd_hash_lookup (info
->wrap_hash
, l
, FALSE
, FALSE
) != NULL
)
550 struct bfd_link_hash_entry
*h
;
552 /* This symbol is being wrapped. We want to replace all
553 references to SYM with references to __wrap_SYM. */
555 amt
= strlen (l
) + sizeof WRAP
+ 1;
556 n
= (char *) bfd_malloc (amt
);
564 h
= bfd_link_hash_lookup (info
->hash
, n
, create
, TRUE
, follow
);
572 #define REAL "__real_"
575 && CONST_STRNEQ (l
, REAL
)
576 && bfd_hash_lookup (info
->wrap_hash
, l
+ sizeof REAL
- 1,
577 FALSE
, FALSE
) != NULL
)
580 struct bfd_link_hash_entry
*h
;
582 /* This is a reference to __real_SYM, where SYM is being
583 wrapped. We want to replace all references to __real_SYM
584 with references to SYM. */
586 amt
= strlen (l
+ sizeof REAL
- 1) + 2;
587 n
= (char *) bfd_malloc (amt
);
593 strcat (n
, l
+ sizeof REAL
- 1);
594 h
= bfd_link_hash_lookup (info
->hash
, n
, create
, TRUE
, follow
);
602 return bfd_link_hash_lookup (info
->hash
, string
, create
, copy
, follow
);
605 /* Traverse a generic link hash table. Differs from bfd_hash_traverse
606 in the treatment of warning symbols. When warning symbols are
607 created they replace the real symbol, so you don't get to see the
608 real symbol in a bfd_hash_travere. This traversal calls func with
612 bfd_link_hash_traverse
613 (struct bfd_link_hash_table
*htab
,
614 bfd_boolean (*func
) (struct bfd_link_hash_entry
*, void *),
619 htab
->table
.frozen
= 1;
620 for (i
= 0; i
< htab
->table
.size
; i
++)
622 struct bfd_link_hash_entry
*p
;
624 p
= (struct bfd_link_hash_entry
*) htab
->table
.table
[i
];
625 for (; p
!= NULL
; p
= (struct bfd_link_hash_entry
*) p
->root
.next
)
626 if (!(*func
) (p
->type
== bfd_link_hash_warning
? p
->u
.i
.link
: p
, info
))
630 htab
->table
.frozen
= 0;
633 /* Add a symbol to the linker hash table undefs list. */
636 bfd_link_add_undef (struct bfd_link_hash_table
*table
,
637 struct bfd_link_hash_entry
*h
)
639 BFD_ASSERT (h
->u
.undef
.next
== NULL
);
640 if (table
->undefs_tail
!= NULL
)
641 table
->undefs_tail
->u
.undef
.next
= h
;
642 if (table
->undefs
== NULL
)
644 table
->undefs_tail
= h
;
647 /* The undefs list was designed so that in normal use we don't need to
648 remove entries. However, if symbols on the list are changed from
649 bfd_link_hash_undefined to either bfd_link_hash_undefweak or
650 bfd_link_hash_new for some reason, then they must be removed from the
651 list. Failure to do so might result in the linker attempting to add
652 the symbol to the list again at a later stage. */
655 bfd_link_repair_undef_list (struct bfd_link_hash_table
*table
)
657 struct bfd_link_hash_entry
**pun
;
659 pun
= &table
->undefs
;
662 struct bfd_link_hash_entry
*h
= *pun
;
664 if (h
->type
== bfd_link_hash_new
665 || h
->type
== bfd_link_hash_undefweak
)
667 *pun
= h
->u
.undef
.next
;
668 h
->u
.undef
.next
= NULL
;
669 if (h
== table
->undefs_tail
)
671 if (pun
== &table
->undefs
)
672 table
->undefs_tail
= NULL
;
674 /* pun points at an u.undef.next field. Go back to
675 the start of the link_hash_entry. */
676 table
->undefs_tail
= (struct bfd_link_hash_entry
*)
677 ((char *) pun
- ((char *) &h
->u
.undef
.next
- (char *) h
));
682 pun
= &h
->u
.undef
.next
;
686 /* Routine to create an entry in a generic link hash table. */
688 struct bfd_hash_entry
*
689 _bfd_generic_link_hash_newfunc (struct bfd_hash_entry
*entry
,
690 struct bfd_hash_table
*table
,
693 /* Allocate the structure if it has not already been allocated by a
697 entry
= (struct bfd_hash_entry
*)
698 bfd_hash_allocate (table
, sizeof (struct generic_link_hash_entry
));
703 /* Call the allocation method of the superclass. */
704 entry
= _bfd_link_hash_newfunc (entry
, table
, string
);
707 struct generic_link_hash_entry
*ret
;
709 /* Set local fields. */
710 ret
= (struct generic_link_hash_entry
*) entry
;
711 ret
->written
= FALSE
;
718 /* Create a generic link hash table. */
720 struct bfd_link_hash_table
*
721 _bfd_generic_link_hash_table_create (bfd
*abfd
)
723 struct generic_link_hash_table
*ret
;
724 bfd_size_type amt
= sizeof (struct generic_link_hash_table
);
726 ret
= (struct generic_link_hash_table
*) bfd_malloc (amt
);
729 if (! _bfd_link_hash_table_init (&ret
->root
, abfd
,
730 _bfd_generic_link_hash_newfunc
,
731 sizeof (struct generic_link_hash_entry
)))
740 _bfd_generic_link_hash_table_free (struct bfd_link_hash_table
*hash
)
742 struct generic_link_hash_table
*ret
743 = (struct generic_link_hash_table
*) hash
;
745 bfd_hash_table_free (&ret
->root
.table
);
749 /* Grab the symbols for an object file when doing a generic link. We
750 store the symbols in the outsymbols field. We need to keep them
751 around for the entire link to ensure that we only read them once.
752 If we read them multiple times, we might wind up with relocs and
753 the hash table pointing to different instances of the symbol
757 bfd_generic_link_read_symbols (bfd
*abfd
)
759 if (bfd_get_outsymbols (abfd
) == NULL
)
764 symsize
= bfd_get_symtab_upper_bound (abfd
);
767 bfd_get_outsymbols (abfd
) = (struct bfd_symbol
**) bfd_alloc (abfd
,
769 if (bfd_get_outsymbols (abfd
) == NULL
&& symsize
!= 0)
771 symcount
= bfd_canonicalize_symtab (abfd
, bfd_get_outsymbols (abfd
));
774 bfd_get_symcount (abfd
) = symcount
;
780 /* Generic function to add symbols to from an object file to the
781 global hash table. This version does not automatically collect
782 constructors by name. */
785 _bfd_generic_link_add_symbols (bfd
*abfd
, struct bfd_link_info
*info
)
787 return generic_link_add_symbols (abfd
, info
, FALSE
);
790 /* Generic function to add symbols from an object file to the global
791 hash table. This version automatically collects constructors by
792 name, as the collect2 program does. It should be used for any
793 target which does not provide some other mechanism for setting up
794 constructors and destructors; these are approximately those targets
795 for which gcc uses collect2 and do not support stabs. */
798 _bfd_generic_link_add_symbols_collect (bfd
*abfd
, struct bfd_link_info
*info
)
800 return generic_link_add_symbols (abfd
, info
, TRUE
);
803 /* Indicate that we are only retrieving symbol values from this
804 section. We want the symbols to act as though the values in the
805 file are absolute. */
808 _bfd_generic_link_just_syms (asection
*sec
,
809 struct bfd_link_info
*info ATTRIBUTE_UNUSED
)
811 sec
->sec_info_type
= SEC_INFO_TYPE_JUST_SYMS
;
812 sec
->output_section
= bfd_abs_section_ptr
;
813 sec
->output_offset
= sec
->vma
;
816 /* Copy the type of a symbol assiciated with a linker hast table entry.
817 Override this so that symbols created in linker scripts get their
818 type from the RHS of the assignment.
819 The default implementation does nothing. */
821 _bfd_generic_copy_link_hash_symbol_type (bfd
*abfd ATTRIBUTE_UNUSED
,
822 struct bfd_link_hash_entry
* hdest ATTRIBUTE_UNUSED
,
823 struct bfd_link_hash_entry
* hsrc ATTRIBUTE_UNUSED
)
827 /* Add symbols from an object file to the global hash table. */
830 generic_link_add_symbols (bfd
*abfd
,
831 struct bfd_link_info
*info
,
836 switch (bfd_get_format (abfd
))
839 ret
= generic_link_add_object_symbols (abfd
, info
, collect
);
842 ret
= (_bfd_generic_link_add_archive_symbols
845 ? generic_link_check_archive_element_collect
846 : generic_link_check_archive_element_no_collect
)));
849 bfd_set_error (bfd_error_wrong_format
);
856 /* Add symbols from an object file to the global hash table. */
859 generic_link_add_object_symbols (bfd
*abfd
,
860 struct bfd_link_info
*info
,
863 bfd_size_type symcount
;
864 struct bfd_symbol
**outsyms
;
866 if (!bfd_generic_link_read_symbols (abfd
))
868 symcount
= _bfd_generic_link_get_symcount (abfd
);
869 outsyms
= _bfd_generic_link_get_symbols (abfd
);
870 return generic_link_add_symbol_list (abfd
, info
, symcount
, outsyms
, collect
);
873 /* We build a hash table of all symbols defined in an archive. */
875 /* An archive symbol may be defined by multiple archive elements.
876 This linked list is used to hold the elements. */
880 struct archive_list
*next
;
884 /* An entry in an archive hash table. */
886 struct archive_hash_entry
888 struct bfd_hash_entry root
;
889 /* Where the symbol is defined. */
890 struct archive_list
*defs
;
893 /* An archive hash table itself. */
895 struct archive_hash_table
897 struct bfd_hash_table table
;
900 /* Create a new entry for an archive hash table. */
902 static struct bfd_hash_entry
*
903 archive_hash_newfunc (struct bfd_hash_entry
*entry
,
904 struct bfd_hash_table
*table
,
907 struct archive_hash_entry
*ret
= (struct archive_hash_entry
*) entry
;
909 /* Allocate the structure if it has not already been allocated by a
912 ret
= (struct archive_hash_entry
*)
913 bfd_hash_allocate (table
, sizeof (struct archive_hash_entry
));
917 /* Call the allocation method of the superclass. */
918 ret
= ((struct archive_hash_entry
*)
919 bfd_hash_newfunc ((struct bfd_hash_entry
*) ret
, table
, string
));
923 /* Initialize the local fields. */
930 /* Initialize an archive hash table. */
933 archive_hash_table_init
934 (struct archive_hash_table
*table
,
935 struct bfd_hash_entry
*(*newfunc
) (struct bfd_hash_entry
*,
936 struct bfd_hash_table
*,
938 unsigned int entsize
)
940 return bfd_hash_table_init (&table
->table
, newfunc
, entsize
);
943 /* Look up an entry in an archive hash table. */
945 #define archive_hash_lookup(t, string, create, copy) \
946 ((struct archive_hash_entry *) \
947 bfd_hash_lookup (&(t)->table, (string), (create), (copy)))
949 /* Allocate space in an archive hash table. */
951 #define archive_hash_allocate(t, size) bfd_hash_allocate (&(t)->table, (size))
953 /* Free an archive hash table. */
955 #define archive_hash_table_free(t) bfd_hash_table_free (&(t)->table)
957 /* Generic function to add symbols from an archive file to the global
958 hash file. This function presumes that the archive symbol table
959 has already been read in (this is normally done by the
960 bfd_check_format entry point). It looks through the undefined and
961 common symbols and searches the archive symbol table for them. If
962 it finds an entry, it includes the associated object file in the
965 The old linker looked through the archive symbol table for
966 undefined symbols. We do it the other way around, looking through
967 undefined symbols for symbols defined in the archive. The
968 advantage of the newer scheme is that we only have to look through
969 the list of undefined symbols once, whereas the old method had to
970 re-search the symbol table each time a new object file was added.
972 The CHECKFN argument is used to see if an object file should be
973 included. CHECKFN should set *PNEEDED to TRUE if the object file
974 should be included, and must also call the bfd_link_info
975 add_archive_element callback function and handle adding the symbols
976 to the global hash table. CHECKFN must notice if the callback
977 indicates a substitute BFD, and arrange to add those symbols instead
978 if it does so. CHECKFN should only return FALSE if some sort of
981 For some formats, such as a.out, it is possible to look through an
982 object file but not actually include it in the link. The
983 archive_pass field in a BFD is used to avoid checking the symbols
984 of an object files too many times. When an object is included in
985 the link, archive_pass is set to -1. If an object is scanned but
986 not included, archive_pass is set to the pass number. The pass
987 number is incremented each time a new object file is included. The
988 pass number is used because when a new object file is included it
989 may create new undefined symbols which cause a previously examined
990 object file to be included. */
993 _bfd_generic_link_add_archive_symbols
995 struct bfd_link_info
*info
,
996 bfd_boolean (*checkfn
) (bfd
*, struct bfd_link_info
*, bfd_boolean
*))
1000 register carsym
*arsym
;
1002 struct archive_hash_table arsym_hash
;
1004 struct bfd_link_hash_entry
**pundef
;
1006 if (! bfd_has_map (abfd
))
1008 /* An empty archive is a special case. */
1009 if (bfd_openr_next_archived_file (abfd
, NULL
) == NULL
)
1011 bfd_set_error (bfd_error_no_armap
);
1015 arsyms
= bfd_ardata (abfd
)->symdefs
;
1016 arsym_end
= arsyms
+ bfd_ardata (abfd
)->symdef_count
;
1018 /* In order to quickly determine whether an symbol is defined in
1019 this archive, we build a hash table of the symbols. */
1020 if (! archive_hash_table_init (&arsym_hash
, archive_hash_newfunc
,
1021 sizeof (struct archive_hash_entry
)))
1023 for (arsym
= arsyms
, indx
= 0; arsym
< arsym_end
; arsym
++, indx
++)
1025 struct archive_hash_entry
*arh
;
1026 struct archive_list
*l
, **pp
;
1028 arh
= archive_hash_lookup (&arsym_hash
, arsym
->name
, TRUE
, FALSE
);
1031 l
= ((struct archive_list
*)
1032 archive_hash_allocate (&arsym_hash
, sizeof (struct archive_list
)));
1036 for (pp
= &arh
->defs
; *pp
!= NULL
; pp
= &(*pp
)->next
)
1042 /* The archive_pass field in the archive itself is used to
1043 initialize PASS, sine we may search the same archive multiple
1045 pass
= abfd
->archive_pass
+ 1;
1047 /* New undefined symbols are added to the end of the list, so we
1048 only need to look through it once. */
1049 pundef
= &info
->hash
->undefs
;
1050 while (*pundef
!= NULL
)
1052 struct bfd_link_hash_entry
*h
;
1053 struct archive_hash_entry
*arh
;
1054 struct archive_list
*l
;
1058 /* When a symbol is defined, it is not necessarily removed from
1060 if (h
->type
!= bfd_link_hash_undefined
1061 && h
->type
!= bfd_link_hash_common
)
1063 /* Remove this entry from the list, for general cleanliness
1064 and because we are going to look through the list again
1065 if we search any more libraries. We can't remove the
1066 entry if it is the tail, because that would lose any
1067 entries we add to the list later on (it would also cause
1068 us to lose track of whether the symbol has been
1070 if (*pundef
!= info
->hash
->undefs_tail
)
1071 *pundef
= (*pundef
)->u
.undef
.next
;
1073 pundef
= &(*pundef
)->u
.undef
.next
;
1077 /* Look for this symbol in the archive symbol map. */
1078 arh
= archive_hash_lookup (&arsym_hash
, h
->root
.string
, FALSE
, FALSE
);
1081 /* If we haven't found the exact symbol we're looking for,
1082 let's look for its import thunk */
1083 if (info
->pei386_auto_import
)
1085 bfd_size_type amt
= strlen (h
->root
.string
) + 10;
1086 char *buf
= (char *) bfd_malloc (amt
);
1090 sprintf (buf
, "__imp_%s", h
->root
.string
);
1091 arh
= archive_hash_lookup (&arsym_hash
, buf
, FALSE
, FALSE
);
1096 pundef
= &(*pundef
)->u
.undef
.next
;
1100 /* Look at all the objects which define this symbol. */
1101 for (l
= arh
->defs
; l
!= NULL
; l
= l
->next
)
1106 /* If the symbol has gotten defined along the way, quit. */
1107 if (h
->type
!= bfd_link_hash_undefined
1108 && h
->type
!= bfd_link_hash_common
)
1111 element
= bfd_get_elt_at_index (abfd
, l
->indx
);
1112 if (element
== NULL
)
1115 /* If we've already included this element, or if we've
1116 already checked it on this pass, continue. */
1117 if (element
->archive_pass
== -1
1118 || element
->archive_pass
== pass
)
1121 /* If we can't figure this element out, just ignore it. */
1122 if (! bfd_check_format (element
, bfd_object
))
1124 element
->archive_pass
= -1;
1128 /* CHECKFN will see if this element should be included, and
1129 go ahead and include it if appropriate. */
1130 if (! (*checkfn
) (element
, info
, &needed
))
1134 element
->archive_pass
= pass
;
1137 element
->archive_pass
= -1;
1139 /* Increment the pass count to show that we may need to
1140 recheck object files which were already checked. */
1145 pundef
= &(*pundef
)->u
.undef
.next
;
1148 archive_hash_table_free (&arsym_hash
);
1150 /* Save PASS in case we are called again. */
1151 abfd
->archive_pass
= pass
;
1156 archive_hash_table_free (&arsym_hash
);
1160 /* See if we should include an archive element. This version is used
1161 when we do not want to automatically collect constructors based on
1162 the symbol name, presumably because we have some other mechanism
1163 for finding them. */
1166 generic_link_check_archive_element_no_collect (
1168 struct bfd_link_info
*info
,
1169 bfd_boolean
*pneeded
)
1171 return generic_link_check_archive_element (abfd
, info
, pneeded
, FALSE
);
1174 /* See if we should include an archive element. This version is used
1175 when we want to automatically collect constructors based on the
1176 symbol name, as collect2 does. */
1179 generic_link_check_archive_element_collect (bfd
*abfd
,
1180 struct bfd_link_info
*info
,
1181 bfd_boolean
*pneeded
)
1183 return generic_link_check_archive_element (abfd
, info
, pneeded
, TRUE
);
1186 /* See if we should include an archive element. Optionally collect
1190 generic_link_check_archive_element (bfd
*abfd
,
1191 struct bfd_link_info
*info
,
1192 bfd_boolean
*pneeded
,
1193 bfd_boolean collect
)
1195 asymbol
**pp
, **ppend
;
1199 if (!bfd_generic_link_read_symbols (abfd
))
1202 pp
= _bfd_generic_link_get_symbols (abfd
);
1203 ppend
= pp
+ _bfd_generic_link_get_symcount (abfd
);
1204 for (; pp
< ppend
; pp
++)
1207 struct bfd_link_hash_entry
*h
;
1211 /* We are only interested in globally visible symbols. */
1212 if (! bfd_is_com_section (p
->section
)
1213 && (p
->flags
& (BSF_GLOBAL
| BSF_INDIRECT
| BSF_WEAK
)) == 0)
1216 /* We are only interested if we know something about this
1217 symbol, and it is undefined or common. An undefined weak
1218 symbol (type bfd_link_hash_undefweak) is not considered to be
1219 a reference when pulling files out of an archive. See the
1220 SVR4 ABI, p. 4-27. */
1221 h
= bfd_link_hash_lookup (info
->hash
, bfd_asymbol_name (p
), FALSE
,
1224 || (h
->type
!= bfd_link_hash_undefined
1225 && h
->type
!= bfd_link_hash_common
))
1228 /* P is a symbol we are looking for. */
1230 if (! bfd_is_com_section (p
->section
))
1232 bfd_size_type symcount
;
1236 /* This object file defines this symbol, so pull it in. */
1237 if (!(*info
->callbacks
1238 ->add_archive_element
) (info
, abfd
, bfd_asymbol_name (p
),
1241 /* Potentially, the add_archive_element hook may have set a
1242 substitute BFD for us. */
1244 && !bfd_generic_link_read_symbols (abfd
))
1246 symcount
= _bfd_generic_link_get_symcount (abfd
);
1247 symbols
= _bfd_generic_link_get_symbols (abfd
);
1248 if (! generic_link_add_symbol_list (abfd
, info
, symcount
,
1255 /* P is a common symbol. */
1257 if (h
->type
== bfd_link_hash_undefined
)
1263 symbfd
= h
->u
.undef
.abfd
;
1266 /* This symbol was created as undefined from outside
1267 BFD. We assume that we should link in the object
1268 file. This is for the -u option in the linker. */
1269 if (!(*info
->callbacks
1270 ->add_archive_element
) (info
, abfd
, bfd_asymbol_name (p
),
1273 /* Potentially, the add_archive_element hook may have set a
1274 substitute BFD for us. But no symbols are going to get
1275 registered by anything we're returning to from here. */
1280 /* Turn the symbol into a common symbol but do not link in
1281 the object file. This is how a.out works. Object
1282 formats that require different semantics must implement
1283 this function differently. This symbol is already on the
1284 undefs list. We add the section to a common section
1285 attached to symbfd to ensure that it is in a BFD which
1286 will be linked in. */
1287 h
->type
= bfd_link_hash_common
;
1288 h
->u
.c
.p
= (struct bfd_link_hash_common_entry
*)
1289 bfd_hash_allocate (&info
->hash
->table
,
1290 sizeof (struct bfd_link_hash_common_entry
));
1291 if (h
->u
.c
.p
== NULL
)
1294 size
= bfd_asymbol_value (p
);
1297 power
= bfd_log2 (size
);
1300 h
->u
.c
.p
->alignment_power
= power
;
1302 if (p
->section
== bfd_com_section_ptr
)
1303 h
->u
.c
.p
->section
= bfd_make_section_old_way (symbfd
, "COMMON");
1305 h
->u
.c
.p
->section
= bfd_make_section_old_way (symbfd
,
1307 h
->u
.c
.p
->section
->flags
|= SEC_ALLOC
;
1311 /* Adjust the size of the common symbol if necessary. This
1312 is how a.out works. Object formats that require
1313 different semantics must implement this function
1315 if (bfd_asymbol_value (p
) > h
->u
.c
.size
)
1316 h
->u
.c
.size
= bfd_asymbol_value (p
);
1320 /* This archive element is not needed. */
1324 /* Add the symbols from an object file to the global hash table. ABFD
1325 is the object file. INFO is the linker information. SYMBOL_COUNT
1326 is the number of symbols. SYMBOLS is the list of symbols. COLLECT
1327 is TRUE if constructors should be automatically collected by name
1328 as is done by collect2. */
1331 generic_link_add_symbol_list (bfd
*abfd
,
1332 struct bfd_link_info
*info
,
1333 bfd_size_type symbol_count
,
1335 bfd_boolean collect
)
1337 asymbol
**pp
, **ppend
;
1340 ppend
= symbols
+ symbol_count
;
1341 for (; pp
< ppend
; pp
++)
1347 if ((p
->flags
& (BSF_INDIRECT
1352 || bfd_is_und_section (bfd_get_section (p
))
1353 || bfd_is_com_section (bfd_get_section (p
))
1354 || bfd_is_ind_section (bfd_get_section (p
)))
1358 struct generic_link_hash_entry
*h
;
1359 struct bfd_link_hash_entry
*bh
;
1361 string
= name
= bfd_asymbol_name (p
);
1362 if (((p
->flags
& BSF_INDIRECT
) != 0
1363 || bfd_is_ind_section (p
->section
))
1367 string
= bfd_asymbol_name (*pp
);
1369 else if ((p
->flags
& BSF_WARNING
) != 0
1372 /* The name of P is actually the warning string, and the
1373 next symbol is the one to warn about. */
1375 name
= bfd_asymbol_name (*pp
);
1379 if (! (_bfd_generic_link_add_one_symbol
1380 (info
, abfd
, name
, p
->flags
, bfd_get_section (p
),
1381 p
->value
, string
, FALSE
, collect
, &bh
)))
1383 h
= (struct generic_link_hash_entry
*) bh
;
1385 /* If this is a constructor symbol, and the linker didn't do
1386 anything with it, then we want to just pass the symbol
1387 through to the output file. This will happen when
1389 if ((p
->flags
& BSF_CONSTRUCTOR
) != 0
1390 && (h
== NULL
|| h
->root
.type
== bfd_link_hash_new
))
1396 /* Save the BFD symbol so that we don't lose any backend
1397 specific information that may be attached to it. We only
1398 want this one if it gives more information than the
1399 existing one; we don't want to replace a defined symbol
1400 with an undefined one. This routine may be called with a
1401 hash table other than the generic hash table, so we only
1402 do this if we are certain that the hash table is a
1404 if (info
->output_bfd
->xvec
== abfd
->xvec
)
1407 || (! bfd_is_und_section (bfd_get_section (p
))
1408 && (! bfd_is_com_section (bfd_get_section (p
))
1409 || bfd_is_und_section (bfd_get_section (h
->sym
)))))
1412 /* BSF_OLD_COMMON is a hack to support COFF reloc
1413 reading, and it should go away when the COFF
1414 linker is switched to the new version. */
1415 if (bfd_is_com_section (bfd_get_section (p
)))
1416 p
->flags
|= BSF_OLD_COMMON
;
1420 /* Store a back pointer from the symbol to the hash
1421 table entry for the benefit of relaxation code until
1422 it gets rewritten to not use asymbol structures.
1423 Setting this is also used to check whether these
1424 symbols were set up by the generic linker. */
1432 /* We use a state table to deal with adding symbols from an object
1433 file. The first index into the state table describes the symbol
1434 from the object file. The second index into the state table is the
1435 type of the symbol in the hash table. */
1437 /* The symbol from the object file is turned into one of these row
1442 UNDEF_ROW
, /* Undefined. */
1443 UNDEFW_ROW
, /* Weak undefined. */
1444 DEF_ROW
, /* Defined. */
1445 DEFW_ROW
, /* Weak defined. */
1446 COMMON_ROW
, /* Common. */
1447 INDR_ROW
, /* Indirect. */
1448 WARN_ROW
, /* Warning. */
1449 SET_ROW
/* Member of set. */
1452 /* apparently needed for Hitachi 3050R(HI-UX/WE2)? */
1455 /* The actions to take in the state table. */
1460 UND
, /* Mark symbol undefined. */
1461 WEAK
, /* Mark symbol weak undefined. */
1462 DEF
, /* Mark symbol defined. */
1463 DEFW
, /* Mark symbol weak defined. */
1464 COM
, /* Mark symbol common. */
1465 REF
, /* Mark defined symbol referenced. */
1466 CREF
, /* Possibly warn about common reference to defined symbol. */
1467 CDEF
, /* Define existing common symbol. */
1468 NOACT
, /* No action. */
1469 BIG
, /* Mark symbol common using largest size. */
1470 MDEF
, /* Multiple definition error. */
1471 MIND
, /* Multiple indirect symbols. */
1472 IND
, /* Make indirect symbol. */
1473 CIND
, /* Make indirect symbol from existing common symbol. */
1474 SET
, /* Add value to set. */
1475 MWARN
, /* Make warning symbol. */
1476 WARN
, /* Issue warning. */
1477 CWARN
, /* Warn if referenced, else MWARN. */
1478 CYCLE
, /* Repeat with symbol pointed to. */
1479 REFC
, /* Mark indirect symbol referenced and then CYCLE. */
1480 WARNC
/* Issue warning and then CYCLE. */
1483 /* The state table itself. The first index is a link_row and the
1484 second index is a bfd_link_hash_type. */
1486 static const enum link_action link_action
[8][8] =
1488 /* current\prev new undef undefw def defw com indr warn */
1489 /* UNDEF_ROW */ {UND
, NOACT
, UND
, REF
, REF
, NOACT
, REFC
, WARNC
},
1490 /* UNDEFW_ROW */ {WEAK
, NOACT
, NOACT
, REF
, REF
, NOACT
, REFC
, WARNC
},
1491 /* DEF_ROW */ {DEF
, DEF
, DEF
, MDEF
, DEF
, CDEF
, MDEF
, CYCLE
},
1492 /* DEFW_ROW */ {DEFW
, DEFW
, DEFW
, NOACT
, NOACT
, NOACT
, NOACT
, CYCLE
},
1493 /* COMMON_ROW */ {COM
, COM
, COM
, CREF
, COM
, BIG
, REFC
, WARNC
},
1494 /* INDR_ROW */ {IND
, IND
, IND
, MDEF
, IND
, CIND
, MIND
, CYCLE
},
1495 /* WARN_ROW */ {MWARN
, WARN
, WARN
, CWARN
, CWARN
, WARN
, CWARN
, NOACT
},
1496 /* SET_ROW */ {SET
, SET
, SET
, SET
, SET
, SET
, CYCLE
, CYCLE
}
1499 /* Most of the entries in the LINK_ACTION table are straightforward,
1500 but a few are somewhat subtle.
1502 A reference to an indirect symbol (UNDEF_ROW/indr or
1503 UNDEFW_ROW/indr) is counted as a reference both to the indirect
1504 symbol and to the symbol the indirect symbol points to.
1506 A reference to a warning symbol (UNDEF_ROW/warn or UNDEFW_ROW/warn)
1507 causes the warning to be issued.
1509 A common definition of an indirect symbol (COMMON_ROW/indr) is
1510 treated as a multiple definition error. Likewise for an indirect
1511 definition of a common symbol (INDR_ROW/com).
1513 An indirect definition of a warning (INDR_ROW/warn) does not cause
1514 the warning to be issued.
1516 If a warning is created for an indirect symbol (WARN_ROW/indr) no
1517 warning is created for the symbol the indirect symbol points to.
1519 Adding an entry to a set does not count as a reference to a set,
1520 and no warning is issued (SET_ROW/warn). */
1522 /* Return the BFD in which a hash entry has been defined, if known. */
1525 hash_entry_bfd (struct bfd_link_hash_entry
*h
)
1527 while (h
->type
== bfd_link_hash_warning
)
1533 case bfd_link_hash_undefined
:
1534 case bfd_link_hash_undefweak
:
1535 return h
->u
.undef
.abfd
;
1536 case bfd_link_hash_defined
:
1537 case bfd_link_hash_defweak
:
1538 return h
->u
.def
.section
->owner
;
1539 case bfd_link_hash_common
:
1540 return h
->u
.c
.p
->section
->owner
;
1545 /* Add a symbol to the global hash table.
1546 ABFD is the BFD the symbol comes from.
1547 NAME is the name of the symbol.
1548 FLAGS is the BSF_* bits associated with the symbol.
1549 SECTION is the section in which the symbol is defined; this may be
1550 bfd_und_section_ptr or bfd_com_section_ptr.
1551 VALUE is the value of the symbol, relative to the section.
1552 STRING is used for either an indirect symbol, in which case it is
1553 the name of the symbol to indirect to, or a warning symbol, in
1554 which case it is the warning string.
1555 COPY is TRUE if NAME or STRING must be copied into locally
1556 allocated memory if they need to be saved.
1557 COLLECT is TRUE if we should automatically collect gcc constructor
1558 or destructor names as collect2 does.
1559 HASHP, if not NULL, is a place to store the created hash table
1560 entry; if *HASHP is not NULL, the caller has already looked up
1561 the hash table entry, and stored it in *HASHP. */
1564 _bfd_generic_link_add_one_symbol (struct bfd_link_info
*info
,
1572 bfd_boolean collect
,
1573 struct bfd_link_hash_entry
**hashp
)
1576 struct bfd_link_hash_entry
*h
;
1579 BFD_ASSERT (section
!= NULL
);
1581 if (bfd_is_ind_section (section
)
1582 || (flags
& BSF_INDIRECT
) != 0)
1584 else if ((flags
& BSF_WARNING
) != 0)
1586 else if ((flags
& BSF_CONSTRUCTOR
) != 0)
1588 else if (bfd_is_und_section (section
))
1590 if ((flags
& BSF_WEAK
) != 0)
1595 else if ((flags
& BSF_WEAK
) != 0)
1597 else if (bfd_is_com_section (section
))
1602 if (hashp
!= NULL
&& *hashp
!= NULL
)
1606 if (row
== UNDEF_ROW
|| row
== UNDEFW_ROW
)
1607 h
= bfd_wrapped_link_hash_lookup (abfd
, info
, name
, TRUE
, copy
, FALSE
);
1609 h
= bfd_link_hash_lookup (info
->hash
, name
, TRUE
, copy
, FALSE
);
1618 if (info
->notice_all
1619 || (info
->notice_hash
!= NULL
1620 && bfd_hash_lookup (info
->notice_hash
, name
, FALSE
, FALSE
) != NULL
))
1622 if (! (*info
->callbacks
->notice
) (info
, h
,
1623 abfd
, section
, value
, flags
, string
))
1632 enum link_action action
;
1635 action
= link_action
[(int) row
][(int) h
->type
];
1646 /* Make a new undefined symbol. */
1647 h
->type
= bfd_link_hash_undefined
;
1648 h
->u
.undef
.abfd
= abfd
;
1649 bfd_link_add_undef (info
->hash
, h
);
1653 /* Make a new weak undefined symbol. */
1654 h
->type
= bfd_link_hash_undefweak
;
1655 h
->u
.undef
.abfd
= abfd
;
1659 /* We have found a definition for a symbol which was
1660 previously common. */
1661 BFD_ASSERT (h
->type
== bfd_link_hash_common
);
1662 if (! ((*info
->callbacks
->multiple_common
)
1663 (info
, h
, abfd
, bfd_link_hash_defined
, 0)))
1669 enum bfd_link_hash_type oldtype
;
1671 /* Define a symbol. */
1674 h
->type
= bfd_link_hash_defweak
;
1676 h
->type
= bfd_link_hash_defined
;
1677 h
->u
.def
.section
= section
;
1678 h
->u
.def
.value
= value
;
1680 /* If we have been asked to, we act like collect2 and
1681 identify all functions that might be global
1682 constructors and destructors and pass them up in a
1683 callback. We only do this for certain object file
1684 types, since many object file types can handle this
1686 if (collect
&& name
[0] == '_')
1690 /* A constructor or destructor name starts like this:
1691 _+GLOBAL_[_.$][ID][_.$] where the first [_.$] and
1692 the second are the same character (we accept any
1693 character there, in case a new object file format
1694 comes along with even worse naming restrictions). */
1696 #define CONS_PREFIX "GLOBAL_"
1697 #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1)
1702 if (s
[0] == 'G' && CONST_STRNEQ (s
, CONS_PREFIX
))
1706 c
= s
[CONS_PREFIX_LEN
+ 1];
1707 if ((c
== 'I' || c
== 'D')
1708 && s
[CONS_PREFIX_LEN
] == s
[CONS_PREFIX_LEN
+ 2])
1710 /* If this is a definition of a symbol which
1711 was previously weakly defined, we are in
1712 trouble. We have already added a
1713 constructor entry for the weak defined
1714 symbol, and now we are trying to add one
1715 for the new symbol. Fortunately, this case
1716 should never arise in practice. */
1717 if (oldtype
== bfd_link_hash_defweak
)
1720 if (! ((*info
->callbacks
->constructor
)
1722 h
->root
.string
, abfd
, section
, value
)))
1732 /* We have found a common definition for a symbol. */
1733 if (h
->type
== bfd_link_hash_new
)
1734 bfd_link_add_undef (info
->hash
, h
);
1735 h
->type
= bfd_link_hash_common
;
1736 h
->u
.c
.p
= (struct bfd_link_hash_common_entry
*)
1737 bfd_hash_allocate (&info
->hash
->table
,
1738 sizeof (struct bfd_link_hash_common_entry
));
1739 if (h
->u
.c
.p
== NULL
)
1742 h
->u
.c
.size
= value
;
1744 /* Select a default alignment based on the size. This may
1745 be overridden by the caller. */
1749 power
= bfd_log2 (value
);
1752 h
->u
.c
.p
->alignment_power
= power
;
1755 /* The section of a common symbol is only used if the common
1756 symbol is actually allocated. It basically provides a
1757 hook for the linker script to decide which output section
1758 the common symbols should be put in. In most cases, the
1759 section of a common symbol will be bfd_com_section_ptr,
1760 the code here will choose a common symbol section named
1761 "COMMON", and the linker script will contain *(COMMON) in
1762 the appropriate place. A few targets use separate common
1763 sections for small symbols, and they require special
1765 if (section
== bfd_com_section_ptr
)
1767 h
->u
.c
.p
->section
= bfd_make_section_old_way (abfd
, "COMMON");
1768 h
->u
.c
.p
->section
->flags
|= SEC_ALLOC
;
1770 else if (section
->owner
!= abfd
)
1772 h
->u
.c
.p
->section
= bfd_make_section_old_way (abfd
,
1774 h
->u
.c
.p
->section
->flags
|= SEC_ALLOC
;
1777 h
->u
.c
.p
->section
= section
;
1781 /* A reference to a defined symbol. */
1782 if (h
->u
.undef
.next
== NULL
&& info
->hash
->undefs_tail
!= h
)
1783 h
->u
.undef
.next
= h
;
1787 /* We have found a common definition for a symbol which
1788 already had a common definition. Use the maximum of the
1789 two sizes, and use the section required by the larger symbol. */
1790 BFD_ASSERT (h
->type
== bfd_link_hash_common
);
1791 if (! ((*info
->callbacks
->multiple_common
)
1792 (info
, h
, abfd
, bfd_link_hash_common
, value
)))
1794 if (value
> h
->u
.c
.size
)
1798 h
->u
.c
.size
= value
;
1800 /* Select a default alignment based on the size. This may
1801 be overridden by the caller. */
1802 power
= bfd_log2 (value
);
1805 h
->u
.c
.p
->alignment_power
= power
;
1807 /* Some systems have special treatment for small commons,
1808 hence we want to select the section used by the larger
1809 symbol. This makes sure the symbol does not go in a
1810 small common section if it is now too large. */
1811 if (section
== bfd_com_section_ptr
)
1814 = bfd_make_section_old_way (abfd
, "COMMON");
1815 h
->u
.c
.p
->section
->flags
|= SEC_ALLOC
;
1817 else if (section
->owner
!= abfd
)
1820 = bfd_make_section_old_way (abfd
, section
->name
);
1821 h
->u
.c
.p
->section
->flags
|= SEC_ALLOC
;
1824 h
->u
.c
.p
->section
= section
;
1829 /* We have found a common definition for a symbol which
1830 was already defined. */
1831 if (! ((*info
->callbacks
->multiple_common
)
1832 (info
, h
, abfd
, bfd_link_hash_common
, value
)))
1837 /* Multiple indirect symbols. This is OK if they both point
1838 to the same symbol. */
1839 if (strcmp (h
->u
.i
.link
->root
.string
, string
) == 0)
1843 /* Handle a multiple definition. */
1844 if (! ((*info
->callbacks
->multiple_definition
)
1845 (info
, h
, abfd
, section
, value
)))
1850 /* Create an indirect symbol from an existing common symbol. */
1851 BFD_ASSERT (h
->type
== bfd_link_hash_common
);
1852 if (! ((*info
->callbacks
->multiple_common
)
1853 (info
, h
, abfd
, bfd_link_hash_indirect
, 0)))
1857 /* Create an indirect symbol. */
1859 struct bfd_link_hash_entry
*inh
;
1861 /* STRING is the name of the symbol we want to indirect
1863 inh
= bfd_wrapped_link_hash_lookup (abfd
, info
, string
, TRUE
,
1867 if (inh
->type
== bfd_link_hash_indirect
1868 && inh
->u
.i
.link
== h
)
1870 (*_bfd_error_handler
)
1871 (_("%B: indirect symbol `%s' to `%s' is a loop"),
1872 abfd
, name
, string
);
1873 bfd_set_error (bfd_error_invalid_operation
);
1876 if (inh
->type
== bfd_link_hash_new
)
1878 inh
->type
= bfd_link_hash_undefined
;
1879 inh
->u
.undef
.abfd
= abfd
;
1880 bfd_link_add_undef (info
->hash
, inh
);
1883 /* If the indirect symbol has been referenced, we need to
1884 push the reference down to the symbol we are
1886 if (h
->type
!= bfd_link_hash_new
)
1892 h
->type
= bfd_link_hash_indirect
;
1898 /* Add an entry to a set. */
1899 if (! (*info
->callbacks
->add_to_set
) (info
, h
, BFD_RELOC_CTOR
,
1900 abfd
, section
, value
))
1905 /* Issue a warning and cycle. */
1906 if (h
->u
.i
.warning
!= NULL
)
1908 if (! (*info
->callbacks
->warning
) (info
, h
->u
.i
.warning
,
1909 h
->root
.string
, abfd
,
1912 /* Only issue a warning once. */
1913 h
->u
.i
.warning
= NULL
;
1917 /* Try again with the referenced symbol. */
1923 /* A reference to an indirect symbol. */
1924 if (h
->u
.undef
.next
== NULL
&& info
->hash
->undefs_tail
!= h
)
1925 h
->u
.undef
.next
= h
;
1931 /* Issue a warning. */
1932 if (! (*info
->callbacks
->warning
) (info
, string
, h
->root
.string
,
1933 hash_entry_bfd (h
), NULL
, 0))
1938 /* Warn if this symbol has been referenced already,
1939 otherwise add a warning. A symbol has been referenced if
1940 the u.undef.next field is not NULL, or it is the tail of the
1941 undefined symbol list. The REF case above helps to
1943 if (h
->u
.undef
.next
!= NULL
|| info
->hash
->undefs_tail
== h
)
1945 if (! (*info
->callbacks
->warning
) (info
, string
, h
->root
.string
,
1946 hash_entry_bfd (h
), NULL
, 0))
1952 /* Make a warning symbol. */
1954 struct bfd_link_hash_entry
*sub
;
1956 /* STRING is the warning to give. */
1957 sub
= ((struct bfd_link_hash_entry
*)
1958 ((*info
->hash
->table
.newfunc
)
1959 (NULL
, &info
->hash
->table
, h
->root
.string
)));
1963 sub
->type
= bfd_link_hash_warning
;
1966 sub
->u
.i
.warning
= string
;
1970 size_t len
= strlen (string
) + 1;
1972 w
= (char *) bfd_hash_allocate (&info
->hash
->table
, len
);
1975 memcpy (w
, string
, len
);
1976 sub
->u
.i
.warning
= w
;
1979 bfd_hash_replace (&info
->hash
->table
,
1980 (struct bfd_hash_entry
*) h
,
1981 (struct bfd_hash_entry
*) sub
);
1993 /* Generic final link routine. */
1996 _bfd_generic_final_link (bfd
*abfd
, struct bfd_link_info
*info
)
2000 struct bfd_link_order
*p
;
2002 struct generic_write_global_symbol_info wginfo
;
2004 bfd_get_outsymbols (abfd
) = NULL
;
2005 bfd_get_symcount (abfd
) = 0;
2008 /* Mark all sections which will be included in the output file. */
2009 for (o
= abfd
->sections
; o
!= NULL
; o
= o
->next
)
2010 for (p
= o
->map_head
.link_order
; p
!= NULL
; p
= p
->next
)
2011 if (p
->type
== bfd_indirect_link_order
)
2012 p
->u
.indirect
.section
->linker_mark
= TRUE
;
2014 /* Build the output symbol table. */
2015 for (sub
= info
->input_bfds
; sub
!= NULL
; sub
= sub
->link_next
)
2016 if (! _bfd_generic_link_output_symbols (abfd
, sub
, info
, &outsymalloc
))
2019 /* Accumulate the global symbols. */
2021 wginfo
.output_bfd
= abfd
;
2022 wginfo
.psymalloc
= &outsymalloc
;
2023 _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info
),
2024 _bfd_generic_link_write_global_symbol
,
2027 /* Make sure we have a trailing NULL pointer on OUTSYMBOLS. We
2028 shouldn't really need one, since we have SYMCOUNT, but some old
2029 code still expects one. */
2030 if (! generic_add_output_symbol (abfd
, &outsymalloc
, NULL
))
2033 if (info
->relocatable
)
2035 /* Allocate space for the output relocs for each section. */
2036 for (o
= abfd
->sections
; o
!= NULL
; o
= o
->next
)
2039 for (p
= o
->map_head
.link_order
; p
!= NULL
; p
= p
->next
)
2041 if (p
->type
== bfd_section_reloc_link_order
2042 || p
->type
== bfd_symbol_reloc_link_order
)
2044 else if (p
->type
== bfd_indirect_link_order
)
2046 asection
*input_section
;
2053 input_section
= p
->u
.indirect
.section
;
2054 input_bfd
= input_section
->owner
;
2055 relsize
= bfd_get_reloc_upper_bound (input_bfd
,
2059 relocs
= (arelent
**) bfd_malloc (relsize
);
2060 if (!relocs
&& relsize
!= 0)
2062 symbols
= _bfd_generic_link_get_symbols (input_bfd
);
2063 reloc_count
= bfd_canonicalize_reloc (input_bfd
,
2068 if (reloc_count
< 0)
2070 BFD_ASSERT ((unsigned long) reloc_count
2071 == input_section
->reloc_count
);
2072 o
->reloc_count
+= reloc_count
;
2075 if (o
->reloc_count
> 0)
2079 amt
= o
->reloc_count
;
2080 amt
*= sizeof (arelent
*);
2081 o
->orelocation
= (struct reloc_cache_entry
**) bfd_alloc (abfd
, amt
);
2082 if (!o
->orelocation
)
2084 o
->flags
|= SEC_RELOC
;
2085 /* Reset the count so that it can be used as an index
2086 when putting in the output relocs. */
2092 /* Handle all the link order information for the sections. */
2093 for (o
= abfd
->sections
; o
!= NULL
; o
= o
->next
)
2095 for (p
= o
->map_head
.link_order
; p
!= NULL
; p
= p
->next
)
2099 case bfd_section_reloc_link_order
:
2100 case bfd_symbol_reloc_link_order
:
2101 if (! _bfd_generic_reloc_link_order (abfd
, info
, o
, p
))
2104 case bfd_indirect_link_order
:
2105 if (! default_indirect_link_order (abfd
, info
, o
, p
, TRUE
))
2109 if (! _bfd_default_link_order (abfd
, info
, o
, p
))
2119 /* Add an output symbol to the output BFD. */
2122 generic_add_output_symbol (bfd
*output_bfd
, size_t *psymalloc
, asymbol
*sym
)
2124 if (bfd_get_symcount (output_bfd
) >= *psymalloc
)
2129 if (*psymalloc
== 0)
2134 amt
*= sizeof (asymbol
*);
2135 newsyms
= (asymbol
**) bfd_realloc (bfd_get_outsymbols (output_bfd
), amt
);
2136 if (newsyms
== NULL
)
2138 bfd_get_outsymbols (output_bfd
) = newsyms
;
2141 bfd_get_outsymbols (output_bfd
) [bfd_get_symcount (output_bfd
)] = sym
;
2143 ++ bfd_get_symcount (output_bfd
);
2148 /* Handle the symbols for an input BFD. */
2151 _bfd_generic_link_output_symbols (bfd
*output_bfd
,
2153 struct bfd_link_info
*info
,
2159 if (!bfd_generic_link_read_symbols (input_bfd
))
2162 /* Create a filename symbol if we are supposed to. */
2163 if (info
->create_object_symbols_section
!= NULL
)
2167 for (sec
= input_bfd
->sections
; sec
!= NULL
; sec
= sec
->next
)
2169 if (sec
->output_section
== info
->create_object_symbols_section
)
2173 newsym
= bfd_make_empty_symbol (input_bfd
);
2176 newsym
->name
= input_bfd
->filename
;
2178 newsym
->flags
= BSF_LOCAL
| BSF_FILE
;
2179 newsym
->section
= sec
;
2181 if (! generic_add_output_symbol (output_bfd
, psymalloc
,
2190 /* Adjust the values of the globally visible symbols, and write out
2192 sym_ptr
= _bfd_generic_link_get_symbols (input_bfd
);
2193 sym_end
= sym_ptr
+ _bfd_generic_link_get_symcount (input_bfd
);
2194 for (; sym_ptr
< sym_end
; sym_ptr
++)
2197 struct generic_link_hash_entry
*h
;
2202 if ((sym
->flags
& (BSF_INDIRECT
2207 || bfd_is_und_section (bfd_get_section (sym
))
2208 || bfd_is_com_section (bfd_get_section (sym
))
2209 || bfd_is_ind_section (bfd_get_section (sym
)))
2211 if (sym
->udata
.p
!= NULL
)
2212 h
= (struct generic_link_hash_entry
*) sym
->udata
.p
;
2213 else if ((sym
->flags
& BSF_CONSTRUCTOR
) != 0)
2215 /* This case normally means that the main linker code
2216 deliberately ignored this constructor symbol. We
2217 should just pass it through. This will screw up if
2218 the constructor symbol is from a different,
2219 non-generic, object file format, but the case will
2220 only arise when linking with -r, which will probably
2221 fail anyhow, since there will be no way to represent
2222 the relocs in the output format being used. */
2225 else if (bfd_is_und_section (bfd_get_section (sym
)))
2226 h
= ((struct generic_link_hash_entry
*)
2227 bfd_wrapped_link_hash_lookup (output_bfd
, info
,
2228 bfd_asymbol_name (sym
),
2229 FALSE
, FALSE
, TRUE
));
2231 h
= _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info
),
2232 bfd_asymbol_name (sym
),
2233 FALSE
, FALSE
, TRUE
);
2237 /* Force all references to this symbol to point to
2238 the same area in memory. It is possible that
2239 this routine will be called with a hash table
2240 other than a generic hash table, so we double
2242 if (info
->output_bfd
->xvec
== input_bfd
->xvec
)
2245 *sym_ptr
= sym
= h
->sym
;
2248 switch (h
->root
.type
)
2251 case bfd_link_hash_new
:
2253 case bfd_link_hash_undefined
:
2255 case bfd_link_hash_undefweak
:
2256 sym
->flags
|= BSF_WEAK
;
2258 case bfd_link_hash_indirect
:
2259 h
= (struct generic_link_hash_entry
*) h
->root
.u
.i
.link
;
2261 case bfd_link_hash_defined
:
2262 sym
->flags
|= BSF_GLOBAL
;
2263 sym
->flags
&=~ BSF_CONSTRUCTOR
;
2264 sym
->value
= h
->root
.u
.def
.value
;
2265 sym
->section
= h
->root
.u
.def
.section
;
2267 case bfd_link_hash_defweak
:
2268 sym
->flags
|= BSF_WEAK
;
2269 sym
->flags
&=~ BSF_CONSTRUCTOR
;
2270 sym
->value
= h
->root
.u
.def
.value
;
2271 sym
->section
= h
->root
.u
.def
.section
;
2273 case bfd_link_hash_common
:
2274 sym
->value
= h
->root
.u
.c
.size
;
2275 sym
->flags
|= BSF_GLOBAL
;
2276 if (! bfd_is_com_section (sym
->section
))
2278 BFD_ASSERT (bfd_is_und_section (sym
->section
));
2279 sym
->section
= bfd_com_section_ptr
;
2281 /* We do not set the section of the symbol to
2282 h->root.u.c.p->section. That value was saved so
2283 that we would know where to allocate the symbol
2284 if it was defined. In this case the type is
2285 still bfd_link_hash_common, so we did not define
2286 it, so we do not want to use that section. */
2292 /* This switch is straight from the old code in
2293 write_file_locals in ldsym.c. */
2294 if (info
->strip
== strip_all
2295 || (info
->strip
== strip_some
2296 && bfd_hash_lookup (info
->keep_hash
, bfd_asymbol_name (sym
),
2297 FALSE
, FALSE
) == NULL
))
2299 else if ((sym
->flags
& (BSF_GLOBAL
| BSF_WEAK
)) != 0)
2301 /* If this symbol is marked as occurring now, rather
2302 than at the end, output it now. This is used for
2303 COFF C_EXT FCN symbols. FIXME: There must be a
2305 if (bfd_asymbol_bfd (sym
) == input_bfd
2306 && (sym
->flags
& BSF_NOT_AT_END
) != 0)
2311 else if (bfd_is_ind_section (sym
->section
))
2313 else if ((sym
->flags
& BSF_DEBUGGING
) != 0)
2315 if (info
->strip
== strip_none
)
2320 else if (bfd_is_und_section (sym
->section
)
2321 || bfd_is_com_section (sym
->section
))
2323 else if ((sym
->flags
& BSF_LOCAL
) != 0)
2325 if ((sym
->flags
& BSF_WARNING
) != 0)
2329 switch (info
->discard
)
2335 case discard_sec_merge
:
2337 if (info
->relocatable
2338 || ! (sym
->section
->flags
& SEC_MERGE
))
2342 if (bfd_is_local_label (input_bfd
, sym
))
2353 else if ((sym
->flags
& BSF_CONSTRUCTOR
))
2355 if (info
->strip
!= strip_all
)
2360 else if (sym
->flags
== 0
2361 && (sym
->section
->owner
->flags
& BFD_PLUGIN
) != 0)
2362 /* LTO doesn't set symbol information. We get here with the
2363 generic linker for a symbol that was "common" but no longer
2364 needs to be global. */
2369 /* If this symbol is in a section which is not being included
2370 in the output file, then we don't want to output the
2372 if (!bfd_is_abs_section (sym
->section
)
2373 && bfd_section_removed_from_list (output_bfd
,
2374 sym
->section
->output_section
))
2379 if (! generic_add_output_symbol (output_bfd
, psymalloc
, sym
))
2389 /* Set the section and value of a generic BFD symbol based on a linker
2390 hash table entry. */
2393 set_symbol_from_hash (asymbol
*sym
, struct bfd_link_hash_entry
*h
)
2400 case bfd_link_hash_new
:
2401 /* This can happen when a constructor symbol is seen but we are
2402 not building constructors. */
2403 if (sym
->section
!= NULL
)
2405 BFD_ASSERT ((sym
->flags
& BSF_CONSTRUCTOR
) != 0);
2409 sym
->flags
|= BSF_CONSTRUCTOR
;
2410 sym
->section
= bfd_abs_section_ptr
;
2414 case bfd_link_hash_undefined
:
2415 sym
->section
= bfd_und_section_ptr
;
2418 case bfd_link_hash_undefweak
:
2419 sym
->section
= bfd_und_section_ptr
;
2421 sym
->flags
|= BSF_WEAK
;
2423 case bfd_link_hash_defined
:
2424 sym
->section
= h
->u
.def
.section
;
2425 sym
->value
= h
->u
.def
.value
;
2427 case bfd_link_hash_defweak
:
2428 sym
->flags
|= BSF_WEAK
;
2429 sym
->section
= h
->u
.def
.section
;
2430 sym
->value
= h
->u
.def
.value
;
2432 case bfd_link_hash_common
:
2433 sym
->value
= h
->u
.c
.size
;
2434 if (sym
->section
== NULL
)
2435 sym
->section
= bfd_com_section_ptr
;
2436 else if (! bfd_is_com_section (sym
->section
))
2438 BFD_ASSERT (bfd_is_und_section (sym
->section
));
2439 sym
->section
= bfd_com_section_ptr
;
2441 /* Do not set the section; see _bfd_generic_link_output_symbols. */
2443 case bfd_link_hash_indirect
:
2444 case bfd_link_hash_warning
:
2445 /* FIXME: What should we do here? */
2450 /* Write out a global symbol, if it hasn't already been written out.
2451 This is called for each symbol in the hash table. */
2454 _bfd_generic_link_write_global_symbol (struct generic_link_hash_entry
*h
,
2457 struct generic_write_global_symbol_info
*wginfo
=
2458 (struct generic_write_global_symbol_info
*) data
;
2466 if (wginfo
->info
->strip
== strip_all
2467 || (wginfo
->info
->strip
== strip_some
2468 && bfd_hash_lookup (wginfo
->info
->keep_hash
, h
->root
.root
.string
,
2469 FALSE
, FALSE
) == NULL
))
2476 sym
= bfd_make_empty_symbol (wginfo
->output_bfd
);
2479 sym
->name
= h
->root
.root
.string
;
2483 set_symbol_from_hash (sym
, &h
->root
);
2485 sym
->flags
|= BSF_GLOBAL
;
2487 if (! generic_add_output_symbol (wginfo
->output_bfd
, wginfo
->psymalloc
,
2490 /* FIXME: No way to return failure. */
2497 /* Create a relocation. */
2500 _bfd_generic_reloc_link_order (bfd
*abfd
,
2501 struct bfd_link_info
*info
,
2503 struct bfd_link_order
*link_order
)
2507 if (! info
->relocatable
)
2509 if (sec
->orelocation
== NULL
)
2512 r
= (arelent
*) bfd_alloc (abfd
, sizeof (arelent
));
2516 r
->address
= link_order
->offset
;
2517 r
->howto
= bfd_reloc_type_lookup (abfd
, link_order
->u
.reloc
.p
->reloc
);
2520 bfd_set_error (bfd_error_bad_value
);
2524 /* Get the symbol to use for the relocation. */
2525 if (link_order
->type
== bfd_section_reloc_link_order
)
2526 r
->sym_ptr_ptr
= link_order
->u
.reloc
.p
->u
.section
->symbol_ptr_ptr
;
2529 struct generic_link_hash_entry
*h
;
2531 h
= ((struct generic_link_hash_entry
*)
2532 bfd_wrapped_link_hash_lookup (abfd
, info
,
2533 link_order
->u
.reloc
.p
->u
.name
,
2534 FALSE
, FALSE
, TRUE
));
2538 if (! ((*info
->callbacks
->unattached_reloc
)
2539 (info
, link_order
->u
.reloc
.p
->u
.name
, NULL
, NULL
, 0)))
2541 bfd_set_error (bfd_error_bad_value
);
2544 r
->sym_ptr_ptr
= &h
->sym
;
2547 /* If this is an inplace reloc, write the addend to the object file.
2548 Otherwise, store it in the reloc addend. */
2549 if (! r
->howto
->partial_inplace
)
2550 r
->addend
= link_order
->u
.reloc
.p
->addend
;
2554 bfd_reloc_status_type rstat
;
2559 size
= bfd_get_reloc_size (r
->howto
);
2560 buf
= (bfd_byte
*) bfd_zmalloc (size
);
2563 rstat
= _bfd_relocate_contents (r
->howto
, abfd
,
2564 (bfd_vma
) link_order
->u
.reloc
.p
->addend
,
2571 case bfd_reloc_outofrange
:
2573 case bfd_reloc_overflow
:
2574 if (! ((*info
->callbacks
->reloc_overflow
)
2576 (link_order
->type
== bfd_section_reloc_link_order
2577 ? bfd_section_name (abfd
, link_order
->u
.reloc
.p
->u
.section
)
2578 : link_order
->u
.reloc
.p
->u
.name
),
2579 r
->howto
->name
, link_order
->u
.reloc
.p
->addend
,
2587 loc
= link_order
->offset
* bfd_octets_per_byte (abfd
);
2588 ok
= bfd_set_section_contents (abfd
, sec
, buf
, loc
, size
);
2596 sec
->orelocation
[sec
->reloc_count
] = r
;
2602 /* Allocate a new link_order for a section. */
2604 struct bfd_link_order
*
2605 bfd_new_link_order (bfd
*abfd
, asection
*section
)
2607 bfd_size_type amt
= sizeof (struct bfd_link_order
);
2608 struct bfd_link_order
*new_lo
;
2610 new_lo
= (struct bfd_link_order
*) bfd_zalloc (abfd
, amt
);
2614 new_lo
->type
= bfd_undefined_link_order
;
2616 if (section
->map_tail
.link_order
!= NULL
)
2617 section
->map_tail
.link_order
->next
= new_lo
;
2619 section
->map_head
.link_order
= new_lo
;
2620 section
->map_tail
.link_order
= new_lo
;
2625 /* Default link order processing routine. Note that we can not handle
2626 the reloc_link_order types here, since they depend upon the details
2627 of how the particular backends generates relocs. */
2630 _bfd_default_link_order (bfd
*abfd
,
2631 struct bfd_link_info
*info
,
2633 struct bfd_link_order
*link_order
)
2635 switch (link_order
->type
)
2637 case bfd_undefined_link_order
:
2638 case bfd_section_reloc_link_order
:
2639 case bfd_symbol_reloc_link_order
:
2642 case bfd_indirect_link_order
:
2643 return default_indirect_link_order (abfd
, info
, sec
, link_order
,
2645 case bfd_data_link_order
:
2646 return default_data_link_order (abfd
, info
, sec
, link_order
);
2650 /* Default routine to handle a bfd_data_link_order. */
2653 default_data_link_order (bfd
*abfd
,
2654 struct bfd_link_info
*info ATTRIBUTE_UNUSED
,
2656 struct bfd_link_order
*link_order
)
2664 BFD_ASSERT ((sec
->flags
& SEC_HAS_CONTENTS
) != 0);
2666 size
= link_order
->size
;
2670 fill
= link_order
->u
.data
.contents
;
2671 fill_size
= link_order
->u
.data
.size
;
2674 fill
= abfd
->arch_info
->fill (size
, bfd_big_endian (abfd
),
2675 (sec
->flags
& SEC_CODE
) != 0);
2679 else if (fill_size
< size
)
2682 fill
= (bfd_byte
*) bfd_malloc (size
);
2687 memset (p
, (int) link_order
->u
.data
.contents
[0], (size_t) size
);
2692 memcpy (p
, link_order
->u
.data
.contents
, fill_size
);
2696 while (size
>= fill_size
);
2698 memcpy (p
, link_order
->u
.data
.contents
, (size_t) size
);
2699 size
= link_order
->size
;
2703 loc
= link_order
->offset
* bfd_octets_per_byte (abfd
);
2704 result
= bfd_set_section_contents (abfd
, sec
, fill
, loc
, size
);
2706 if (fill
!= link_order
->u
.data
.contents
)
2711 /* Default routine to handle a bfd_indirect_link_order. */
2714 default_indirect_link_order (bfd
*output_bfd
,
2715 struct bfd_link_info
*info
,
2716 asection
*output_section
,
2717 struct bfd_link_order
*link_order
,
2718 bfd_boolean generic_linker
)
2720 asection
*input_section
;
2722 bfd_byte
*contents
= NULL
;
2723 bfd_byte
*new_contents
;
2724 bfd_size_type sec_size
;
2727 BFD_ASSERT ((output_section
->flags
& SEC_HAS_CONTENTS
) != 0);
2729 input_section
= link_order
->u
.indirect
.section
;
2730 input_bfd
= input_section
->owner
;
2731 if (input_section
->size
== 0)
2734 BFD_ASSERT (input_section
->output_section
== output_section
);
2735 BFD_ASSERT (input_section
->output_offset
== link_order
->offset
);
2736 BFD_ASSERT (input_section
->size
== link_order
->size
);
2738 if (info
->relocatable
2739 && input_section
->reloc_count
> 0
2740 && output_section
->orelocation
== NULL
)
2742 /* Space has not been allocated for the output relocations.
2743 This can happen when we are called by a specific backend
2744 because somebody is attempting to link together different
2745 types of object files. Handling this case correctly is
2746 difficult, and sometimes impossible. */
2747 (*_bfd_error_handler
)
2748 (_("Attempt to do relocatable link with %s input and %s output"),
2749 bfd_get_target (input_bfd
), bfd_get_target (output_bfd
));
2750 bfd_set_error (bfd_error_wrong_format
);
2754 if (! generic_linker
)
2759 /* Get the canonical symbols. The generic linker will always
2760 have retrieved them by this point, but we are being called by
2761 a specific linker, presumably because we are linking
2762 different types of object files together. */
2763 if (!bfd_generic_link_read_symbols (input_bfd
))
2766 /* Since we have been called by a specific linker, rather than
2767 the generic linker, the values of the symbols will not be
2768 right. They will be the values as seen in the input file,
2769 not the values of the final link. We need to fix them up
2770 before we can relocate the section. */
2771 sympp
= _bfd_generic_link_get_symbols (input_bfd
);
2772 symppend
= sympp
+ _bfd_generic_link_get_symcount (input_bfd
);
2773 for (; sympp
< symppend
; sympp
++)
2776 struct bfd_link_hash_entry
*h
;
2780 if ((sym
->flags
& (BSF_INDIRECT
2785 || bfd_is_und_section (bfd_get_section (sym
))
2786 || bfd_is_com_section (bfd_get_section (sym
))
2787 || bfd_is_ind_section (bfd_get_section (sym
)))
2789 /* sym->udata may have been set by
2790 generic_link_add_symbol_list. */
2791 if (sym
->udata
.p
!= NULL
)
2792 h
= (struct bfd_link_hash_entry
*) sym
->udata
.p
;
2793 else if (bfd_is_und_section (bfd_get_section (sym
)))
2794 h
= bfd_wrapped_link_hash_lookup (output_bfd
, info
,
2795 bfd_asymbol_name (sym
),
2796 FALSE
, FALSE
, TRUE
);
2798 h
= bfd_link_hash_lookup (info
->hash
,
2799 bfd_asymbol_name (sym
),
2800 FALSE
, FALSE
, TRUE
);
2802 set_symbol_from_hash (sym
, h
);
2807 if ((output_section
->flags
& (SEC_GROUP
| SEC_LINKER_CREATED
)) == SEC_GROUP
2808 && input_section
->size
!= 0)
2810 /* Group section contents are set by bfd_elf_set_group_contents. */
2811 if (!output_bfd
->output_has_begun
)
2813 /* FIXME: This hack ensures bfd_elf_set_group_contents is called. */
2814 if (!bfd_set_section_contents (output_bfd
, output_section
, "", 0, 1))
2817 new_contents
= output_section
->contents
;
2818 BFD_ASSERT (new_contents
!= NULL
);
2819 BFD_ASSERT (input_section
->output_offset
== 0);
2823 /* Get and relocate the section contents. */
2824 sec_size
= (input_section
->rawsize
> input_section
->size
2825 ? input_section
->rawsize
2826 : input_section
->size
);
2827 contents
= (bfd_byte
*) bfd_malloc (sec_size
);
2828 if (contents
== NULL
&& sec_size
!= 0)
2830 new_contents
= (bfd_get_relocated_section_contents
2831 (output_bfd
, info
, link_order
, contents
,
2833 _bfd_generic_link_get_symbols (input_bfd
)));
2838 /* Output the section contents. */
2839 loc
= input_section
->output_offset
* bfd_octets_per_byte (output_bfd
);
2840 if (! bfd_set_section_contents (output_bfd
, output_section
,
2841 new_contents
, loc
, input_section
->size
))
2844 if (contents
!= NULL
)
2849 if (contents
!= NULL
)
2854 /* A little routine to count the number of relocs in a link_order
2858 _bfd_count_link_order_relocs (struct bfd_link_order
*link_order
)
2860 register unsigned int c
;
2861 register struct bfd_link_order
*l
;
2864 for (l
= link_order
; l
!= NULL
; l
= l
->next
)
2866 if (l
->type
== bfd_section_reloc_link_order
2867 || l
->type
== bfd_symbol_reloc_link_order
)
2876 bfd_link_split_section
2879 bfd_boolean bfd_link_split_section (bfd *abfd, asection *sec);
2882 Return nonzero if @var{sec} should be split during a
2883 reloceatable or final link.
2885 .#define bfd_link_split_section(abfd, sec) \
2886 . BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec))
2892 _bfd_generic_link_split_section (bfd
*abfd ATTRIBUTE_UNUSED
,
2893 asection
*sec ATTRIBUTE_UNUSED
)
2900 bfd_section_already_linked
2903 bfd_boolean bfd_section_already_linked (bfd *abfd,
2905 struct bfd_link_info *info);
2908 Check if @var{data} has been already linked during a reloceatable
2909 or final link. Return TRUE if it has.
2911 .#define bfd_section_already_linked(abfd, sec, info) \
2912 . BFD_SEND (abfd, _section_already_linked, (abfd, sec, info))
2917 /* Sections marked with the SEC_LINK_ONCE flag should only be linked
2918 once into the output. This routine checks each section, and
2919 arrange to discard it if a section of the same name has already
2920 been linked. This code assumes that all relevant sections have the
2921 SEC_LINK_ONCE flag set; that is, it does not depend solely upon the
2922 section name. bfd_section_already_linked is called via
2923 bfd_map_over_sections. */
2925 /* The hash table. */
2927 static struct bfd_hash_table _bfd_section_already_linked_table
;
2929 /* Support routines for the hash table used by section_already_linked,
2930 initialize the table, traverse, lookup, fill in an entry and remove
2934 bfd_section_already_linked_table_traverse
2935 (bfd_boolean (*func
) (struct bfd_section_already_linked_hash_entry
*,
2936 void *), void *info
)
2938 bfd_hash_traverse (&_bfd_section_already_linked_table
,
2939 (bfd_boolean (*) (struct bfd_hash_entry
*,
2944 struct bfd_section_already_linked_hash_entry
*
2945 bfd_section_already_linked_table_lookup (const char *name
)
2947 return ((struct bfd_section_already_linked_hash_entry
*)
2948 bfd_hash_lookup (&_bfd_section_already_linked_table
, name
,
2953 bfd_section_already_linked_table_insert
2954 (struct bfd_section_already_linked_hash_entry
*already_linked_list
,
2957 struct bfd_section_already_linked
*l
;
2959 /* Allocate the memory from the same obstack as the hash table is
2961 l
= (struct bfd_section_already_linked
*)
2962 bfd_hash_allocate (&_bfd_section_already_linked_table
, sizeof *l
);
2966 l
->next
= already_linked_list
->entry
;
2967 already_linked_list
->entry
= l
;
2971 static struct bfd_hash_entry
*
2972 already_linked_newfunc (struct bfd_hash_entry
*entry ATTRIBUTE_UNUSED
,
2973 struct bfd_hash_table
*table
,
2974 const char *string ATTRIBUTE_UNUSED
)
2976 struct bfd_section_already_linked_hash_entry
*ret
=
2977 (struct bfd_section_already_linked_hash_entry
*)
2978 bfd_hash_allocate (table
, sizeof *ret
);
2989 bfd_section_already_linked_table_init (void)
2991 return bfd_hash_table_init_n (&_bfd_section_already_linked_table
,
2992 already_linked_newfunc
,
2993 sizeof (struct bfd_section_already_linked_hash_entry
),
2998 bfd_section_already_linked_table_free (void)
3000 bfd_hash_table_free (&_bfd_section_already_linked_table
);
3003 /* Report warnings as appropriate for duplicate section SEC.
3004 Return FALSE if we decide to keep SEC after all. */
3007 _bfd_handle_already_linked (asection
*sec
,
3008 struct bfd_section_already_linked
*l
,
3009 struct bfd_link_info
*info
)
3011 switch (sec
->flags
& SEC_LINK_DUPLICATES
)
3016 case SEC_LINK_DUPLICATES_DISCARD
:
3017 /* If we found an LTO IR match for this comdat group on
3018 the first pass, replace it with the LTO output on the
3019 second pass. We can't simply choose real object
3020 files over IR because the first pass may contain a
3021 mix of LTO and normal objects and we must keep the
3022 first match, be it IR or real. */
3023 if (info
->loading_lto_outputs
3024 && (l
->sec
->owner
->flags
& BFD_PLUGIN
) != 0)
3031 case SEC_LINK_DUPLICATES_ONE_ONLY
:
3032 info
->callbacks
->einfo
3033 (_("%B: ignoring duplicate section `%A'\n"),
3037 case SEC_LINK_DUPLICATES_SAME_SIZE
:
3038 if ((l
->sec
->owner
->flags
& BFD_PLUGIN
) != 0)
3040 else if (sec
->size
!= l
->sec
->size
)
3041 info
->callbacks
->einfo
3042 (_("%B: duplicate section `%A' has different size\n"),
3046 case SEC_LINK_DUPLICATES_SAME_CONTENTS
:
3047 if ((l
->sec
->owner
->flags
& BFD_PLUGIN
) != 0)
3049 else if (sec
->size
!= l
->sec
->size
)
3050 info
->callbacks
->einfo
3051 (_("%B: duplicate section `%A' has different size\n"),
3053 else if (sec
->size
!= 0)
3055 bfd_byte
*sec_contents
, *l_sec_contents
= NULL
;
3057 if (!bfd_malloc_and_get_section (sec
->owner
, sec
, &sec_contents
))
3058 info
->callbacks
->einfo
3059 (_("%B: could not read contents of section `%A'\n"),
3061 else if (!bfd_malloc_and_get_section (l
->sec
->owner
, l
->sec
,
3063 info
->callbacks
->einfo
3064 (_("%B: could not read contents of section `%A'\n"),
3065 l
->sec
->owner
, l
->sec
);
3066 else if (memcmp (sec_contents
, l_sec_contents
, sec
->size
) != 0)
3067 info
->callbacks
->einfo
3068 (_("%B: duplicate section `%A' has different contents\n"),
3072 free (sec_contents
);
3074 free (l_sec_contents
);
3079 /* Set the output_section field so that lang_add_section
3080 does not create a lang_input_section structure for this
3081 section. Since there might be a symbol in the section
3082 being discarded, we must retain a pointer to the section
3083 which we are really going to use. */
3084 sec
->output_section
= bfd_abs_section_ptr
;
3085 sec
->kept_section
= l
->sec
;
3089 /* This is used on non-ELF inputs. */
3092 _bfd_generic_section_already_linked (bfd
*abfd ATTRIBUTE_UNUSED
,
3094 struct bfd_link_info
*info
)
3097 struct bfd_section_already_linked
*l
;
3098 struct bfd_section_already_linked_hash_entry
*already_linked_list
;
3100 if ((sec
->flags
& SEC_LINK_ONCE
) == 0)
3103 /* The generic linker doesn't handle section groups. */
3104 if ((sec
->flags
& SEC_GROUP
) != 0)
3107 /* FIXME: When doing a relocatable link, we may have trouble
3108 copying relocations in other sections that refer to local symbols
3109 in the section being discarded. Those relocations will have to
3110 be converted somehow; as of this writing I'm not sure that any of
3111 the backends handle that correctly.
3113 It is tempting to instead not discard link once sections when
3114 doing a relocatable link (technically, they should be discarded
3115 whenever we are building constructors). However, that fails,
3116 because the linker winds up combining all the link once sections
3117 into a single large link once section, which defeats the purpose
3118 of having link once sections in the first place. */
3120 name
= bfd_get_section_name (abfd
, sec
);
3122 already_linked_list
= bfd_section_already_linked_table_lookup (name
);
3124 l
= already_linked_list
->entry
;
3127 /* The section has already been linked. See if we should
3129 return _bfd_handle_already_linked (sec
, l
, info
);
3132 /* This is the first section with this name. Record it. */
3133 if (!bfd_section_already_linked_table_insert (already_linked_list
, sec
))
3134 info
->callbacks
->einfo (_("%F%P: already_linked_table: %E\n"));
3138 /* Choose a neighbouring section to S in OBFD that will be output, or
3139 the absolute section if ADDR is out of bounds of the neighbours. */
3142 _bfd_nearby_section (bfd
*obfd
, asection
*s
, bfd_vma addr
)
3144 asection
*next
, *prev
, *best
;
3146 /* Find preceding kept section. */
3147 for (prev
= s
->prev
; prev
!= NULL
; prev
= prev
->prev
)
3148 if ((prev
->flags
& SEC_EXCLUDE
) == 0
3149 && !bfd_section_removed_from_list (obfd
, prev
))
3152 /* Find following kept section. Start at prev->next because
3153 other sections may have been added after S was removed. */
3154 if (s
->prev
!= NULL
)
3155 next
= s
->prev
->next
;
3157 next
= s
->owner
->sections
;
3158 for (; next
!= NULL
; next
= next
->next
)
3159 if ((next
->flags
& SEC_EXCLUDE
) == 0
3160 && !bfd_section_removed_from_list (obfd
, next
))
3163 /* Choose better of two sections, based on flags. The idea
3164 is to choose a section that will be in the same segment
3165 as S would have been if it was kept. */
3170 best
= bfd_abs_section_ptr
;
3172 else if (next
== NULL
)
3174 else if (((prev
->flags
^ next
->flags
)
3175 & (SEC_ALLOC
| SEC_THREAD_LOCAL
| SEC_LOAD
)) != 0)
3177 if (((next
->flags
^ s
->flags
)
3178 & (SEC_ALLOC
| SEC_THREAD_LOCAL
)) != 0
3179 /* We prefer to choose a loaded section. Section S
3180 doesn't have SEC_LOAD set (it being excluded, that
3181 part of the flag processing didn't happen) so we
3182 can't compare that flag to those of NEXT and PREV. */
3183 || ((prev
->flags
& SEC_LOAD
) != 0
3184 && (next
->flags
& SEC_LOAD
) == 0))
3187 else if (((prev
->flags
^ next
->flags
) & SEC_READONLY
) != 0)
3189 if (((next
->flags
^ s
->flags
) & SEC_READONLY
) != 0)
3192 else if (((prev
->flags
^ next
->flags
) & SEC_CODE
) != 0)
3194 if (((next
->flags
^ s
->flags
) & SEC_CODE
) != 0)
3199 /* Flags we care about are the same. Prefer the following
3200 section if that will result in a positive valued sym. */
3201 if (addr
< next
->vma
)
3208 /* Convert symbols in excluded output sections to use a kept section. */
3211 fix_syms (struct bfd_link_hash_entry
*h
, void *data
)
3213 bfd
*obfd
= (bfd
*) data
;
3215 if (h
->type
== bfd_link_hash_defined
3216 || h
->type
== bfd_link_hash_defweak
)
3218 asection
*s
= h
->u
.def
.section
;
3220 && s
->output_section
!= NULL
3221 && (s
->output_section
->flags
& SEC_EXCLUDE
) != 0
3222 && bfd_section_removed_from_list (obfd
, s
->output_section
))
3226 h
->u
.def
.value
+= s
->output_offset
+ s
->output_section
->vma
;
3227 op
= _bfd_nearby_section (obfd
, s
->output_section
, h
->u
.def
.value
);
3228 h
->u
.def
.value
-= op
->vma
;
3229 h
->u
.def
.section
= op
;
3237 _bfd_fix_excluded_sec_syms (bfd
*obfd
, struct bfd_link_info
*info
)
3239 bfd_link_hash_traverse (info
->hash
, fix_syms
, obfd
);
3244 bfd_generic_define_common_symbol
3247 bfd_boolean bfd_generic_define_common_symbol
3248 (bfd *output_bfd, struct bfd_link_info *info,
3249 struct bfd_link_hash_entry *h);
3252 Convert common symbol @var{h} into a defined symbol.
3253 Return TRUE on success and FALSE on failure.
3255 .#define bfd_define_common_symbol(output_bfd, info, h) \
3256 . BFD_SEND (output_bfd, _bfd_define_common_symbol, (output_bfd, info, h))
3261 bfd_generic_define_common_symbol (bfd
*output_bfd
,
3262 struct bfd_link_info
*info ATTRIBUTE_UNUSED
,
3263 struct bfd_link_hash_entry
*h
)
3265 unsigned int power_of_two
;
3266 bfd_vma alignment
, size
;
3269 BFD_ASSERT (h
!= NULL
&& h
->type
== bfd_link_hash_common
);
3272 power_of_two
= h
->u
.c
.p
->alignment_power
;
3273 section
= h
->u
.c
.p
->section
;
3275 /* Increase the size of the section to align the common symbol.
3276 The alignment must be a power of two. */
3277 alignment
= bfd_octets_per_byte (output_bfd
) << power_of_two
;
3278 BFD_ASSERT (alignment
!= 0 && (alignment
& -alignment
) == alignment
);
3279 section
->size
+= alignment
- 1;
3280 section
->size
&= -alignment
;
3282 /* Adjust the section's overall alignment if necessary. */
3283 if (power_of_two
> section
->alignment_power
)
3284 section
->alignment_power
= power_of_two
;
3286 /* Change the symbol from common to defined. */
3287 h
->type
= bfd_link_hash_defined
;
3288 h
->u
.def
.section
= section
;
3289 h
->u
.def
.value
= section
->size
;
3291 /* Increase the size of the section. */
3292 section
->size
+= size
;
3294 /* Make sure the section is allocated in memory, and make sure that
3295 it is no longer a common section. */
3296 section
->flags
|= SEC_ALLOC
;
3297 section
->flags
&= ~SEC_IS_COMMON
;
3303 bfd_find_version_for_sym
3306 struct bfd_elf_version_tree * bfd_find_version_for_sym
3307 (struct bfd_elf_version_tree *verdefs,
3308 const char *sym_name, bfd_boolean *hide);
3311 Search an elf version script tree for symbol versioning
3312 info and export / don't-export status for a given symbol.
3313 Return non-NULL on success and NULL on failure; also sets
3314 the output @samp{hide} boolean parameter.
3318 struct bfd_elf_version_tree
*
3319 bfd_find_version_for_sym (struct bfd_elf_version_tree
*verdefs
,
3320 const char *sym_name
,
3323 struct bfd_elf_version_tree
*t
;
3324 struct bfd_elf_version_tree
*local_ver
, *global_ver
, *exist_ver
;
3325 struct bfd_elf_version_tree
*star_local_ver
, *star_global_ver
;
3329 star_local_ver
= NULL
;
3330 star_global_ver
= NULL
;
3332 for (t
= verdefs
; t
!= NULL
; t
= t
->next
)
3334 if (t
->globals
.list
!= NULL
)
3336 struct bfd_elf_version_expr
*d
= NULL
;
3338 while ((d
= (*t
->match
) (&t
->globals
, d
, sym_name
)) != NULL
)
3340 if (d
->literal
|| strcmp (d
->pattern
, "*") != 0)
3343 star_global_ver
= t
;
3347 /* If the match is a wildcard pattern, keep looking for
3348 a more explicit, perhaps even local, match. */
3357 if (t
->locals
.list
!= NULL
)
3359 struct bfd_elf_version_expr
*d
= NULL
;
3361 while ((d
= (*t
->match
) (&t
->locals
, d
, sym_name
)) != NULL
)
3363 if (d
->literal
|| strcmp (d
->pattern
, "*") != 0)
3367 /* If the match is a wildcard pattern, keep looking for
3368 a more explicit, perhaps even global, match. */
3371 /* An exact match overrides a global wildcard. */
3373 star_global_ver
= NULL
;
3383 if (global_ver
== NULL
&& local_ver
== NULL
)
3384 global_ver
= star_global_ver
;
3386 if (global_ver
!= NULL
)
3388 /* If we already have a versioned symbol that matches the
3389 node for this symbol, then we don't want to create a
3390 duplicate from the unversioned symbol. Instead hide the
3391 unversioned symbol. */
3392 *hide
= exist_ver
== global_ver
;
3396 if (local_ver
== NULL
)
3397 local_ver
= star_local_ver
;
3399 if (local_ver
!= NULL
)
3410 bfd_hide_sym_by_version
3413 bfd_boolean bfd_hide_sym_by_version
3414 (struct bfd_elf_version_tree *verdefs, const char *sym_name);
3417 Search an elf version script tree for symbol versioning
3418 info for a given symbol. Return TRUE if the symbol is hidden.
3423 bfd_hide_sym_by_version (struct bfd_elf_version_tree
*verdefs
,
3424 const char *sym_name
)
3426 bfd_boolean hidden
= FALSE
;
3427 bfd_find_version_for_sym (verdefs
, sym_name
, &hidden
);