1 /* linker.c -- BFD linker routines
2 Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001
3 Free Software Foundation, Inc.
4 Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support
6 This file is part of BFD, the Binary File Descriptor library.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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 relocateable
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 <<creator>>
153 field of the hash table must be checked to make sure that the
154 hash table was 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 <<creator>> field 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.
226 @findex _bfd_generic_link_add_archive_symbols
227 In most cases the work of looking through the symbols in the
228 archive should be done by the
229 <<_bfd_generic_link_add_archive_symbols>> function. This
230 function builds a hash table from the archive symbol table and
231 looks through the list of undefined symbols to see which
232 elements should be included.
233 <<_bfd_generic_link_add_archive_symbols>> is passed a function
234 to call to make the final decision about adding an archive
235 element to the link and to do the actual work of adding the
236 symbols to the linker hash table.
238 The function passed to
239 <<_bfd_generic_link_add_archive_symbols>> must read the
240 symbols of the archive element and decide whether the archive
241 element should be included in the link. If the element is to
242 be included, the <<add_archive_element>> linker callback
243 routine must be called with the element as an argument, and
244 the elements symbols must be added to the linker hash table
245 just as though the element had itself been passed to the
246 <<_bfd_link_add_symbols>> function.
248 When the a.out <<_bfd_link_add_symbols>> function receives an
249 archive, it calls <<_bfd_generic_link_add_archive_symbols>>
250 passing <<aout_link_check_archive_element>> as the function
251 argument. <<aout_link_check_archive_element>> calls
252 <<aout_link_check_ar_symbols>>. If the latter decides to add
253 the element (an element is only added if it provides a real,
254 non-common, definition for a previously undefined or common
255 symbol) it calls the <<add_archive_element>> callback and then
256 <<aout_link_check_archive_element>> calls
257 <<aout_link_add_symbols>> to actually add the symbols to the
260 The ECOFF back end is unusual in that it does not normally
261 call <<_bfd_generic_link_add_archive_symbols>>, because ECOFF
262 archives already contain a hash table of symbols. The ECOFF
263 back end searches the archive itself to avoid the overhead of
264 creating a new hash table.
267 Performing the Final Link, , Adding Symbols to the Hash Table, Linker Functions
269 Performing the final link
271 @cindex _bfd_link_final_link in target vector
272 @cindex target vector (_bfd_final_link)
273 When all the input files have been processed, the linker calls
274 the <<_bfd_final_link>> entry point of the output BFD. This
275 routine is responsible for producing the final output file,
276 which has several aspects. It must relocate the contents of
277 the input sections and copy the data into the output sections.
278 It must build an output symbol table including any local
279 symbols from the input files and the global symbols from the
280 hash table. When producing relocateable output, it must
281 modify the input relocs and write them into the output file.
282 There may also be object format dependent work to be done.
284 The linker will also call the <<write_object_contents>> entry
285 point when the BFD is closed. The two entry points must work
286 together in order to produce the correct output file.
288 The details of how this works are inevitably dependent upon
289 the specific object file format. The a.out
290 <<_bfd_final_link>> routine is <<NAME(aout,final_link)>>.
293 @* Information provided by the linker::
294 @* Relocating the section contents::
295 @* Writing the symbol table::
299 Information provided by the linker, Relocating the section contents, Performing the Final Link, Performing the Final Link
301 Information provided by the linker
303 Before the linker calls the <<_bfd_final_link>> entry point,
304 it sets up some data structures for the function to use.
306 The <<input_bfds>> field of the <<bfd_link_info>> structure
307 will point to a list of all the input files included in the
308 link. These files are linked through the <<link_next>> field
309 of the <<bfd>> structure.
311 Each section in the output file will have a list of
312 <<link_order>> structures attached to the <<link_order_head>>
313 field (the <<link_order>> structure is defined in
314 <<bfdlink.h>>). These structures describe how to create the
315 contents of the output section in terms of the contents of
316 various input sections, fill constants, and, eventually, other
317 types of information. They also describe relocs that must be
318 created by the BFD backend, but do not correspond to any input
319 file; this is used to support -Ur, which builds constructors
320 while generating a relocateable object file.
323 Relocating the section contents, Writing the symbol table, Information provided by the linker, Performing the Final Link
325 Relocating the section contents
327 The <<_bfd_final_link>> function should look through the
328 <<link_order>> structures attached to each section of the
329 output file. Each <<link_order>> structure should either be
330 handled specially, or it should be passed to the function
331 <<_bfd_default_link_order>> which will do the right thing
332 (<<_bfd_default_link_order>> is defined in <<linker.c>>).
334 For efficiency, a <<link_order>> of type
335 <<bfd_indirect_link_order>> whose associated section belongs
336 to a BFD of the same format as the output BFD must be handled
337 specially. This type of <<link_order>> describes part of an
338 output section in terms of a section belonging to one of the
339 input files. The <<_bfd_final_link>> function should read the
340 contents of the section and any associated relocs, apply the
341 relocs to the section contents, and write out the modified
342 section contents. If performing a relocateable link, the
343 relocs themselves must also be modified and written out.
345 @findex _bfd_relocate_contents
346 @findex _bfd_final_link_relocate
347 The functions <<_bfd_relocate_contents>> and
348 <<_bfd_final_link_relocate>> provide some general support for
349 performing the actual relocations, notably overflow checking.
350 Their arguments include information about the symbol the
351 relocation is against and a <<reloc_howto_type>> argument
352 which describes the relocation to perform. These functions
353 are defined in <<reloc.c>>.
355 The a.out function which handles reading, relocating, and
356 writing section contents is <<aout_link_input_section>>. The
357 actual relocation is done in <<aout_link_input_section_std>>
358 and <<aout_link_input_section_ext>>.
361 Writing the symbol table, , Relocating the section contents, Performing the Final Link
363 Writing the symbol table
365 The <<_bfd_final_link>> function must gather all the symbols
366 in the input files and write them out. It must also write out
367 all the symbols in the global hash table. This must be
368 controlled by the <<strip>> and <<discard>> fields of the
369 <<bfd_link_info>> structure.
371 The local symbols of the input files will not have been
372 entered into the linker hash table. The <<_bfd_final_link>>
373 routine must consider each input file and include the symbols
374 in the output file. It may be convenient to do this when
375 looking through the <<link_order>> structures, or it may be
376 done by stepping through the <<input_bfds>> list.
378 The <<_bfd_final_link>> routine must also traverse the global
379 hash table to gather all the externally visible symbols. It
380 is possible that most of the externally visible symbols may be
381 written out when considering the symbols of each input file,
382 but it is still necessary to traverse the hash table since the
383 linker script may have defined some symbols that are not in
384 any of the input files.
386 The <<strip>> field of the <<bfd_link_info>> structure
387 controls which symbols are written out. The possible values
388 are listed in <<bfdlink.h>>. If the value is <<strip_some>>,
389 then the <<keep_hash>> field of the <<bfd_link_info>>
390 structure is a hash table of symbols to keep; each symbol
391 should be looked up in this hash table, and only symbols which
392 are present should be included in the output file.
394 If the <<strip>> field of the <<bfd_link_info>> structure
395 permits local symbols to be written out, the <<discard>> field
396 is used to further controls which local symbols are included
397 in the output file. If the value is <<discard_l>>, then all
398 local symbols which begin with a certain prefix are discarded;
399 this is controlled by the <<bfd_is_local_label_name>> entry point.
401 The a.out backend handles symbols by calling
402 <<aout_link_write_symbols>> on each input BFD and then
403 traversing the global hash table with the function
404 <<aout_link_write_other_symbol>>. It builds a string table
405 while writing out the symbols, which is written to the output
406 file at the end of <<NAME(aout,final_link)>>.
409 static boolean generic_link_read_symbols
411 static boolean generic_link_add_symbols
412 PARAMS ((bfd
*, struct bfd_link_info
*, boolean collect
));
413 static boolean generic_link_add_object_symbols
414 PARAMS ((bfd
*, struct bfd_link_info
*, boolean collect
));
415 static boolean generic_link_check_archive_element_no_collect
416 PARAMS ((bfd
*, struct bfd_link_info
*, boolean
*pneeded
));
417 static boolean generic_link_check_archive_element_collect
418 PARAMS ((bfd
*, struct bfd_link_info
*, boolean
*pneeded
));
419 static boolean generic_link_check_archive_element
420 PARAMS ((bfd
*, struct bfd_link_info
*, boolean
*pneeded
, boolean collect
));
421 static boolean generic_link_add_symbol_list
422 PARAMS ((bfd
*, struct bfd_link_info
*, bfd_size_type count
, asymbol
**,
424 static bfd
*hash_entry_bfd
PARAMS ((struct bfd_link_hash_entry
*));
425 static void set_symbol_from_hash
426 PARAMS ((asymbol
*, struct bfd_link_hash_entry
*));
427 static boolean generic_add_output_symbol
428 PARAMS ((bfd
*, size_t *psymalloc
, asymbol
*));
429 static boolean default_fill_link_order
430 PARAMS ((bfd
*, struct bfd_link_info
*, asection
*,
431 struct bfd_link_order
*));
432 static boolean default_indirect_link_order
433 PARAMS ((bfd
*, struct bfd_link_info
*, asection
*,
434 struct bfd_link_order
*, boolean
));
436 /* The link hash table structure is defined in bfdlink.h. It provides
437 a base hash table which the backend specific hash tables are built
440 /* Routine to create an entry in the link hash table. */
442 struct bfd_hash_entry
*
443 _bfd_link_hash_newfunc (entry
, table
, string
)
444 struct bfd_hash_entry
*entry
;
445 struct bfd_hash_table
*table
;
448 struct bfd_link_hash_entry
*ret
= (struct bfd_link_hash_entry
*) entry
;
450 /* Allocate the structure if it has not already been allocated by a
452 if (ret
== (struct bfd_link_hash_entry
*) NULL
)
453 ret
= ((struct bfd_link_hash_entry
*)
454 bfd_hash_allocate (table
, sizeof (struct bfd_link_hash_entry
)));
455 if (ret
== (struct bfd_link_hash_entry
*) NULL
)
458 /* Call the allocation method of the superclass. */
459 ret
= ((struct bfd_link_hash_entry
*)
460 bfd_hash_newfunc ((struct bfd_hash_entry
*) ret
, table
, string
));
464 /* Initialize the local fields. */
465 ret
->type
= bfd_link_hash_new
;
469 return (struct bfd_hash_entry
*) ret
;
472 /* Initialize a link hash table. The BFD argument is the one
473 responsible for creating this table. */
476 _bfd_link_hash_table_init (table
, abfd
, newfunc
)
477 struct bfd_link_hash_table
*table
;
479 struct bfd_hash_entry
*(*newfunc
) PARAMS ((struct bfd_hash_entry
*,
480 struct bfd_hash_table
*,
483 table
->creator
= abfd
->xvec
;
484 table
->undefs
= NULL
;
485 table
->undefs_tail
= NULL
;
486 table
->type
= bfd_link_generic_hash_table
;
488 return bfd_hash_table_init (&table
->table
, newfunc
);
491 /* Look up a symbol in a link hash table. If follow is true, we
492 follow bfd_link_hash_indirect and bfd_link_hash_warning links to
495 struct bfd_link_hash_entry
*
496 bfd_link_hash_lookup (table
, string
, create
, copy
, follow
)
497 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
!= (struct bfd_link_hash_entry
*) 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 (abfd
, info
, string
, create
, copy
, follow
)
525 struct bfd_link_info
*info
;
531 if (info
->wrap_hash
!= NULL
)
536 if (*l
== bfd_get_symbol_leading_char (abfd
))
540 #define WRAP "__wrap_"
542 if (bfd_hash_lookup (info
->wrap_hash
, l
, false, false) != NULL
)
545 struct bfd_link_hash_entry
*h
;
547 /* This symbol is being wrapped. We want to replace all
548 references to SYM with references to __wrap_SYM. */
550 n
= (char *) bfd_malloc (strlen (l
) + sizeof WRAP
+ 1);
554 /* Note that symbol_leading_char may be '\0'. */
555 n
[0] = bfd_get_symbol_leading_char (abfd
);
559 h
= bfd_link_hash_lookup (info
->hash
, n
, create
, true, follow
);
567 #define REAL "__real_"
570 && strncmp (l
, REAL
, sizeof REAL
- 1) == 0
571 && bfd_hash_lookup (info
->wrap_hash
, l
+ sizeof REAL
- 1,
572 false, false) != NULL
)
575 struct bfd_link_hash_entry
*h
;
577 /* This is a reference to __real_SYM, where SYM is being
578 wrapped. We want to replace all references to __real_SYM
579 with references to SYM. */
581 n
= (char *) bfd_malloc (strlen (l
+ sizeof REAL
- 1) + 2);
585 /* Note that symbol_leading_char may be '\0'. */
586 n
[0] = bfd_get_symbol_leading_char (abfd
);
588 strcat (n
, l
+ sizeof REAL
- 1);
589 h
= bfd_link_hash_lookup (info
->hash
, n
, create
, true, follow
);
597 return bfd_link_hash_lookup (info
->hash
, string
, create
, copy
, follow
);
600 /* Traverse a generic link hash table. The only reason this is not a
601 macro is to do better type checking. This code presumes that an
602 argument passed as a struct bfd_hash_entry * may be caught as a
603 struct bfd_link_hash_entry * with no explicit cast required on the
607 bfd_link_hash_traverse (table
, func
, info
)
608 struct bfd_link_hash_table
*table
;
609 boolean (*func
) PARAMS ((struct bfd_link_hash_entry
*, PTR
));
612 bfd_hash_traverse (&table
->table
,
613 ((boolean (*) PARAMS ((struct bfd_hash_entry
*, PTR
)))
618 /* Add a symbol to the linker hash table undefs list. */
621 bfd_link_add_undef (table
, h
)
622 struct bfd_link_hash_table
*table
;
623 struct bfd_link_hash_entry
*h
;
625 BFD_ASSERT (h
->next
== NULL
);
626 if (table
->undefs_tail
!= (struct bfd_link_hash_entry
*) NULL
)
627 table
->undefs_tail
->next
= h
;
628 if (table
->undefs
== (struct bfd_link_hash_entry
*) NULL
)
630 table
->undefs_tail
= h
;
633 /* Routine to create an entry in an generic link hash table. */
635 struct bfd_hash_entry
*
636 _bfd_generic_link_hash_newfunc (entry
, table
, string
)
637 struct bfd_hash_entry
*entry
;
638 struct bfd_hash_table
*table
;
641 struct generic_link_hash_entry
*ret
=
642 (struct generic_link_hash_entry
*) entry
;
644 /* Allocate the structure if it has not already been allocated by a
646 if (ret
== (struct generic_link_hash_entry
*) NULL
)
647 ret
= ((struct generic_link_hash_entry
*)
648 bfd_hash_allocate (table
, sizeof (struct generic_link_hash_entry
)));
649 if (ret
== (struct generic_link_hash_entry
*) NULL
)
652 /* Call the allocation method of the superclass. */
653 ret
= ((struct generic_link_hash_entry
*)
654 _bfd_link_hash_newfunc ((struct bfd_hash_entry
*) ret
,
659 /* Set local fields. */
660 ret
->written
= false;
664 return (struct bfd_hash_entry
*) ret
;
667 /* Create an generic link hash table. */
669 struct bfd_link_hash_table
*
670 _bfd_generic_link_hash_table_create (abfd
)
673 struct generic_link_hash_table
*ret
;
675 ret
= ((struct generic_link_hash_table
*)
676 bfd_alloc (abfd
, sizeof (struct generic_link_hash_table
)));
678 return (struct bfd_link_hash_table
*) NULL
;
679 if (! _bfd_link_hash_table_init (&ret
->root
, abfd
,
680 _bfd_generic_link_hash_newfunc
))
683 return (struct bfd_link_hash_table
*) NULL
;
688 /* Grab the symbols for an object file when doing a generic link. We
689 store the symbols in the outsymbols field. We need to keep them
690 around for the entire link to ensure that we only read them once.
691 If we read them multiple times, we might wind up with relocs and
692 the hash table pointing to different instances of the symbol
696 generic_link_read_symbols (abfd
)
699 if (bfd_get_outsymbols (abfd
) == (asymbol
**) NULL
)
704 symsize
= bfd_get_symtab_upper_bound (abfd
);
707 bfd_get_outsymbols (abfd
) = (asymbol
**) bfd_alloc (abfd
, symsize
);
708 if (bfd_get_outsymbols (abfd
) == NULL
&& symsize
!= 0)
710 symcount
= bfd_canonicalize_symtab (abfd
, bfd_get_outsymbols (abfd
));
713 bfd_get_symcount (abfd
) = symcount
;
719 /* Generic function to add symbols to from an object file to the
720 global hash table. This version does not automatically collect
721 constructors by name. */
724 _bfd_generic_link_add_symbols (abfd
, info
)
726 struct bfd_link_info
*info
;
728 return generic_link_add_symbols (abfd
, info
, false);
731 /* Generic function to add symbols from an object file to the global
732 hash table. This version automatically collects constructors by
733 name, as the collect2 program does. It should be used for any
734 target which does not provide some other mechanism for setting up
735 constructors and destructors; these are approximately those targets
736 for which gcc uses collect2 and do not support stabs. */
739 _bfd_generic_link_add_symbols_collect (abfd
, info
)
741 struct bfd_link_info
*info
;
743 return generic_link_add_symbols (abfd
, info
, true);
746 /* Add symbols from an object file to the global hash table. */
749 generic_link_add_symbols (abfd
, info
, collect
)
751 struct bfd_link_info
*info
;
756 switch (bfd_get_format (abfd
))
759 ret
= generic_link_add_object_symbols (abfd
, info
, collect
);
762 ret
= (_bfd_generic_link_add_archive_symbols
765 ? generic_link_check_archive_element_collect
766 : generic_link_check_archive_element_no_collect
)));
769 bfd_set_error (bfd_error_wrong_format
);
776 /* Add symbols from an object file to the global hash table. */
779 generic_link_add_object_symbols (abfd
, info
, collect
)
781 struct bfd_link_info
*info
;
784 if (! generic_link_read_symbols (abfd
))
786 return generic_link_add_symbol_list (abfd
, info
,
787 _bfd_generic_link_get_symcount (abfd
),
788 _bfd_generic_link_get_symbols (abfd
),
792 /* We build a hash table of all symbols defined in an archive. */
794 /* An archive symbol may be defined by multiple archive elements.
795 This linked list is used to hold the elements. */
799 struct archive_list
*next
;
803 /* An entry in an archive hash table. */
805 struct archive_hash_entry
807 struct bfd_hash_entry root
;
808 /* Where the symbol is defined. */
809 struct archive_list
*defs
;
812 /* An archive hash table itself. */
814 struct archive_hash_table
816 struct bfd_hash_table table
;
819 static struct bfd_hash_entry
*archive_hash_newfunc
820 PARAMS ((struct bfd_hash_entry
*, struct bfd_hash_table
*, const char *));
821 static boolean archive_hash_table_init
822 PARAMS ((struct archive_hash_table
*,
823 struct bfd_hash_entry
*(*) (struct bfd_hash_entry
*,
824 struct bfd_hash_table
*,
827 /* Create a new entry for an archive hash table. */
829 static struct bfd_hash_entry
*
830 archive_hash_newfunc (entry
, table
, string
)
831 struct bfd_hash_entry
*entry
;
832 struct bfd_hash_table
*table
;
835 struct archive_hash_entry
*ret
= (struct archive_hash_entry
*) entry
;
837 /* Allocate the structure if it has not already been allocated by a
839 if (ret
== (struct archive_hash_entry
*) NULL
)
840 ret
= ((struct archive_hash_entry
*)
841 bfd_hash_allocate (table
, sizeof (struct archive_hash_entry
)));
842 if (ret
== (struct archive_hash_entry
*) NULL
)
845 /* Call the allocation method of the superclass. */
846 ret
= ((struct archive_hash_entry
*)
847 bfd_hash_newfunc ((struct bfd_hash_entry
*) ret
, table
, string
));
851 /* Initialize the local fields. */
852 ret
->defs
= (struct archive_list
*) NULL
;
855 return (struct bfd_hash_entry
*) ret
;
858 /* Initialize an archive hash table. */
861 archive_hash_table_init (table
, newfunc
)
862 struct archive_hash_table
*table
;
863 struct bfd_hash_entry
*(*newfunc
) PARAMS ((struct bfd_hash_entry
*,
864 struct bfd_hash_table
*,
867 return bfd_hash_table_init (&table
->table
, newfunc
);
870 /* Look up an entry in an archive hash table. */
872 #define archive_hash_lookup(t, string, create, copy) \
873 ((struct archive_hash_entry *) \
874 bfd_hash_lookup (&(t)->table, (string), (create), (copy)))
876 /* Allocate space in an archive hash table. */
878 #define archive_hash_allocate(t, size) bfd_hash_allocate (&(t)->table, (size))
880 /* Free an archive hash table. */
882 #define archive_hash_table_free(t) bfd_hash_table_free (&(t)->table)
884 /* Generic function to add symbols from an archive file to the global
885 hash file. This function presumes that the archive symbol table
886 has already been read in (this is normally done by the
887 bfd_check_format entry point). It looks through the undefined and
888 common symbols and searches the archive symbol table for them. If
889 it finds an entry, it includes the associated object file in the
892 The old linker looked through the archive symbol table for
893 undefined symbols. We do it the other way around, looking through
894 undefined symbols for symbols defined in the archive. The
895 advantage of the newer scheme is that we only have to look through
896 the list of undefined symbols once, whereas the old method had to
897 re-search the symbol table each time a new object file was added.
899 The CHECKFN argument is used to see if an object file should be
900 included. CHECKFN should set *PNEEDED to true if the object file
901 should be included, and must also call the bfd_link_info
902 add_archive_element callback function and handle adding the symbols
903 to the global hash table. CHECKFN should only return false if some
904 sort of error occurs.
906 For some formats, such as a.out, it is possible to look through an
907 object file but not actually include it in the link. The
908 archive_pass field in a BFD is used to avoid checking the symbols
909 of an object files too many times. When an object is included in
910 the link, archive_pass is set to -1. If an object is scanned but
911 not included, archive_pass is set to the pass number. The pass
912 number is incremented each time a new object file is included. The
913 pass number is used because when a new object file is included it
914 may create new undefined symbols which cause a previously examined
915 object file to be included. */
918 _bfd_generic_link_add_archive_symbols (abfd
, info
, checkfn
)
920 struct bfd_link_info
*info
;
921 boolean (*checkfn
) PARAMS ((bfd
*, struct bfd_link_info
*,
926 register carsym
*arsym
;
928 struct archive_hash_table arsym_hash
;
930 struct bfd_link_hash_entry
**pundef
;
932 if (! bfd_has_map (abfd
))
934 /* An empty archive is a special case. */
935 if (bfd_openr_next_archived_file (abfd
, (bfd
*) NULL
) == NULL
)
937 bfd_set_error (bfd_error_no_armap
);
941 arsyms
= bfd_ardata (abfd
)->symdefs
;
942 arsym_end
= arsyms
+ bfd_ardata (abfd
)->symdef_count
;
944 /* In order to quickly determine whether an symbol is defined in
945 this archive, we build a hash table of the symbols. */
946 if (! archive_hash_table_init (&arsym_hash
, archive_hash_newfunc
))
948 for (arsym
= arsyms
, indx
= 0; arsym
< arsym_end
; arsym
++, indx
++)
950 struct archive_hash_entry
*arh
;
951 struct archive_list
*l
, **pp
;
953 arh
= archive_hash_lookup (&arsym_hash
, arsym
->name
, true, false);
954 if (arh
== (struct archive_hash_entry
*) NULL
)
956 l
= ((struct archive_list
*)
957 archive_hash_allocate (&arsym_hash
, sizeof (struct archive_list
)));
961 for (pp
= &arh
->defs
;
962 *pp
!= (struct archive_list
*) NULL
;
969 /* The archive_pass field in the archive itself is used to
970 initialize PASS, sine we may search the same archive multiple
972 pass
= abfd
->archive_pass
+ 1;
974 /* New undefined symbols are added to the end of the list, so we
975 only need to look through it once. */
976 pundef
= &info
->hash
->undefs
;
977 while (*pundef
!= (struct bfd_link_hash_entry
*) NULL
)
979 struct bfd_link_hash_entry
*h
;
980 struct archive_hash_entry
*arh
;
981 struct archive_list
*l
;
985 /* When a symbol is defined, it is not necessarily removed from
987 if (h
->type
!= bfd_link_hash_undefined
988 && h
->type
!= bfd_link_hash_common
)
990 /* Remove this entry from the list, for general cleanliness
991 and because we are going to look through the list again
992 if we search any more libraries. We can't remove the
993 entry if it is the tail, because that would lose any
994 entries we add to the list later on (it would also cause
995 us to lose track of whether the symbol has been
997 if (*pundef
!= info
->hash
->undefs_tail
)
998 *pundef
= (*pundef
)->next
;
1000 pundef
= &(*pundef
)->next
;
1004 /* Look for this symbol in the archive symbol map. */
1005 arh
= archive_hash_lookup (&arsym_hash
, h
->root
.string
, false, false);
1006 if (arh
== (struct archive_hash_entry
*) NULL
)
1008 /* If we haven't found the exact symbol we're looking for,
1009 let's look for its import thunk */
1010 if (info
->pei386_auto_import
)
1012 char *buf
= (char *) bfd_malloc (strlen (h
->root
.string
) + 10);
1016 sprintf (buf
, "__imp_%s", h
->root
.string
);
1017 arh
= archive_hash_lookup (&arsym_hash
, buf
, false, false);
1020 if (arh
== (struct archive_hash_entry
*) NULL
)
1022 pundef
= &(*pundef
)->next
;
1026 /* Look at all the objects which define this symbol. */
1027 for (l
= arh
->defs
; l
!= (struct archive_list
*) NULL
; l
= l
->next
)
1032 /* If the symbol has gotten defined along the way, quit. */
1033 if (h
->type
!= bfd_link_hash_undefined
1034 && h
->type
!= bfd_link_hash_common
)
1037 element
= bfd_get_elt_at_index (abfd
, l
->indx
);
1038 if (element
== (bfd
*) NULL
)
1041 /* If we've already included this element, or if we've
1042 already checked it on this pass, continue. */
1043 if (element
->archive_pass
== -1
1044 || element
->archive_pass
== pass
)
1047 /* If we can't figure this element out, just ignore it. */
1048 if (! bfd_check_format (element
, bfd_object
))
1050 element
->archive_pass
= -1;
1054 /* CHECKFN will see if this element should be included, and
1055 go ahead and include it if appropriate. */
1056 if (! (*checkfn
) (element
, info
, &needed
))
1060 element
->archive_pass
= pass
;
1063 element
->archive_pass
= -1;
1065 /* Increment the pass count to show that we may need to
1066 recheck object files which were already checked. */
1071 pundef
= &(*pundef
)->next
;
1074 archive_hash_table_free (&arsym_hash
);
1076 /* Save PASS in case we are called again. */
1077 abfd
->archive_pass
= pass
;
1082 archive_hash_table_free (&arsym_hash
);
1086 /* See if we should include an archive element. This version is used
1087 when we do not want to automatically collect constructors based on
1088 the symbol name, presumably because we have some other mechanism
1089 for finding them. */
1092 generic_link_check_archive_element_no_collect (abfd
, info
, pneeded
)
1094 struct bfd_link_info
*info
;
1097 return generic_link_check_archive_element (abfd
, info
, pneeded
, false);
1100 /* See if we should include an archive element. This version is used
1101 when we want to automatically collect constructors based on the
1102 symbol name, as collect2 does. */
1105 generic_link_check_archive_element_collect (abfd
, info
, pneeded
)
1107 struct bfd_link_info
*info
;
1110 return generic_link_check_archive_element (abfd
, info
, pneeded
, true);
1113 /* See if we should include an archive element. Optionally collect
1117 generic_link_check_archive_element (abfd
, info
, pneeded
, collect
)
1119 struct bfd_link_info
*info
;
1123 asymbol
**pp
, **ppend
;
1127 if (! generic_link_read_symbols (abfd
))
1130 pp
= _bfd_generic_link_get_symbols (abfd
);
1131 ppend
= pp
+ _bfd_generic_link_get_symcount (abfd
);
1132 for (; pp
< ppend
; pp
++)
1135 struct bfd_link_hash_entry
*h
;
1139 /* We are only interested in globally visible symbols. */
1140 if (! bfd_is_com_section (p
->section
)
1141 && (p
->flags
& (BSF_GLOBAL
| BSF_INDIRECT
| BSF_WEAK
)) == 0)
1144 /* We are only interested if we know something about this
1145 symbol, and it is undefined or common. An undefined weak
1146 symbol (type bfd_link_hash_undefweak) is not considered to be
1147 a reference when pulling files out of an archive. See the
1148 SVR4 ABI, p. 4-27. */
1149 h
= bfd_link_hash_lookup (info
->hash
, bfd_asymbol_name (p
), false,
1151 if (h
== (struct bfd_link_hash_entry
*) NULL
1152 || (h
->type
!= bfd_link_hash_undefined
1153 && h
->type
!= bfd_link_hash_common
))
1156 /* P is a symbol we are looking for. */
1158 if (! bfd_is_com_section (p
->section
))
1160 bfd_size_type symcount
;
1163 /* This object file defines this symbol, so pull it in. */
1164 if (! (*info
->callbacks
->add_archive_element
) (info
, abfd
,
1165 bfd_asymbol_name (p
)))
1167 symcount
= _bfd_generic_link_get_symcount (abfd
);
1168 symbols
= _bfd_generic_link_get_symbols (abfd
);
1169 if (! generic_link_add_symbol_list (abfd
, info
, symcount
,
1176 /* P is a common symbol. */
1178 if (h
->type
== bfd_link_hash_undefined
)
1184 symbfd
= h
->u
.undef
.abfd
;
1185 if (symbfd
== (bfd
*) NULL
)
1187 /* This symbol was created as undefined from outside
1188 BFD. We assume that we should link in the object
1189 file. This is for the -u option in the linker. */
1190 if (! (*info
->callbacks
->add_archive_element
)
1191 (info
, abfd
, bfd_asymbol_name (p
)))
1197 /* Turn the symbol into a common symbol but do not link in
1198 the object file. This is how a.out works. Object
1199 formats that require different semantics must implement
1200 this function differently. This symbol is already on the
1201 undefs list. We add the section to a common section
1202 attached to symbfd to ensure that it is in a BFD which
1203 will be linked in. */
1204 h
->type
= bfd_link_hash_common
;
1206 ((struct bfd_link_hash_common_entry
*)
1207 bfd_hash_allocate (&info
->hash
->table
,
1208 sizeof (struct bfd_link_hash_common_entry
)));
1209 if (h
->u
.c
.p
== NULL
)
1212 size
= bfd_asymbol_value (p
);
1215 power
= bfd_log2 (size
);
1218 h
->u
.c
.p
->alignment_power
= power
;
1220 if (p
->section
== bfd_com_section_ptr
)
1221 h
->u
.c
.p
->section
= bfd_make_section_old_way (symbfd
, "COMMON");
1223 h
->u
.c
.p
->section
= bfd_make_section_old_way (symbfd
,
1225 h
->u
.c
.p
->section
->flags
= SEC_ALLOC
;
1229 /* Adjust the size of the common symbol if necessary. This
1230 is how a.out works. Object formats that require
1231 different semantics must implement this function
1233 if (bfd_asymbol_value (p
) > h
->u
.c
.size
)
1234 h
->u
.c
.size
= bfd_asymbol_value (p
);
1238 /* This archive element is not needed. */
1242 /* Add the symbols from an object file to the global hash table. ABFD
1243 is the object file. INFO is the linker information. SYMBOL_COUNT
1244 is the number of symbols. SYMBOLS is the list of symbols. COLLECT
1245 is true if constructors should be automatically collected by name
1246 as is done by collect2. */
1249 generic_link_add_symbol_list (abfd
, info
, symbol_count
, symbols
, collect
)
1251 struct bfd_link_info
*info
;
1252 bfd_size_type symbol_count
;
1256 asymbol
**pp
, **ppend
;
1259 ppend
= symbols
+ symbol_count
;
1260 for (; pp
< ppend
; pp
++)
1266 if ((p
->flags
& (BSF_INDIRECT
1271 || bfd_is_und_section (bfd_get_section (p
))
1272 || bfd_is_com_section (bfd_get_section (p
))
1273 || bfd_is_ind_section (bfd_get_section (p
)))
1277 struct generic_link_hash_entry
*h
;
1279 name
= bfd_asymbol_name (p
);
1280 if (((p
->flags
& BSF_INDIRECT
) != 0
1281 || bfd_is_ind_section (p
->section
))
1285 string
= bfd_asymbol_name (*pp
);
1287 else if ((p
->flags
& BSF_WARNING
) != 0
1290 /* The name of P is actually the warning string, and the
1291 next symbol is the one to warn about. */
1294 name
= bfd_asymbol_name (*pp
);
1300 if (! (_bfd_generic_link_add_one_symbol
1301 (info
, abfd
, name
, p
->flags
, bfd_get_section (p
),
1302 p
->value
, string
, false, collect
,
1303 (struct bfd_link_hash_entry
**) &h
)))
1306 /* If this is a constructor symbol, and the linker didn't do
1307 anything with it, then we want to just pass the symbol
1308 through to the output file. This will happen when
1310 if ((p
->flags
& BSF_CONSTRUCTOR
) != 0
1311 && (h
== NULL
|| h
->root
.type
== bfd_link_hash_new
))
1317 /* Save the BFD symbol so that we don't lose any backend
1318 specific information that may be attached to it. We only
1319 want this one if it gives more information than the
1320 existing one; we don't want to replace a defined symbol
1321 with an undefined one. This routine may be called with a
1322 hash table other than the generic hash table, so we only
1323 do this if we are certain that the hash table is a
1325 if (info
->hash
->creator
== abfd
->xvec
)
1327 if (h
->sym
== (asymbol
*) NULL
1328 || (! bfd_is_und_section (bfd_get_section (p
))
1329 && (! bfd_is_com_section (bfd_get_section (p
))
1330 || bfd_is_und_section (bfd_get_section (h
->sym
)))))
1333 /* BSF_OLD_COMMON is a hack to support COFF reloc
1334 reading, and it should go away when the COFF
1335 linker is switched to the new version. */
1336 if (bfd_is_com_section (bfd_get_section (p
)))
1337 p
->flags
|= BSF_OLD_COMMON
;
1341 /* Store a back pointer from the symbol to the hash
1342 table entry for the benefit of relaxation code until
1343 it gets rewritten to not use asymbol structures.
1344 Setting this is also used to check whether these
1345 symbols were set up by the generic linker. */
1346 p
->udata
.p
= (PTR
) h
;
1353 /* We use a state table to deal with adding symbols from an object
1354 file. The first index into the state table describes the symbol
1355 from the object file. The second index into the state table is the
1356 type of the symbol in the hash table. */
1358 /* The symbol from the object file is turned into one of these row
1363 UNDEF_ROW
, /* Undefined. */
1364 UNDEFW_ROW
, /* Weak undefined. */
1365 DEF_ROW
, /* Defined. */
1366 DEFW_ROW
, /* Weak defined. */
1367 COMMON_ROW
, /* Common. */
1368 INDR_ROW
, /* Indirect. */
1369 WARN_ROW
, /* Warning. */
1370 SET_ROW
/* Member of set. */
1373 /* apparently needed for Hitachi 3050R(HI-UX/WE2)? */
1376 /* The actions to take in the state table. */
1381 UND
, /* Mark symbol undefined. */
1382 WEAK
, /* Mark symbol weak undefined. */
1383 DEF
, /* Mark symbol defined. */
1384 DEFW
, /* Mark symbol weak defined. */
1385 COM
, /* Mark symbol common. */
1386 REF
, /* Mark defined symbol referenced. */
1387 CREF
, /* Possibly warn about common reference to defined symbol. */
1388 CDEF
, /* Define existing common symbol. */
1389 NOACT
, /* No action. */
1390 BIG
, /* Mark symbol common using largest size. */
1391 MDEF
, /* Multiple definition error. */
1392 MIND
, /* Multiple indirect symbols. */
1393 IND
, /* Make indirect symbol. */
1394 CIND
, /* Make indirect symbol from existing common symbol. */
1395 SET
, /* Add value to set. */
1396 MWARN
, /* Make warning symbol. */
1397 WARN
, /* Issue warning. */
1398 CWARN
, /* Warn if referenced, else MWARN. */
1399 CYCLE
, /* Repeat with symbol pointed to. */
1400 REFC
, /* Mark indirect symbol referenced and then CYCLE. */
1401 WARNC
/* Issue warning and then CYCLE. */
1404 /* The state table itself. The first index is a link_row and the
1405 second index is a bfd_link_hash_type. */
1407 static const enum link_action link_action
[8][8] =
1409 /* current\prev new undef undefw def defw com indr warn */
1410 /* UNDEF_ROW */ {UND
, NOACT
, UND
, REF
, REF
, NOACT
, REFC
, WARNC
},
1411 /* UNDEFW_ROW */ {WEAK
, NOACT
, NOACT
, REF
, REF
, NOACT
, REFC
, WARNC
},
1412 /* DEF_ROW */ {DEF
, DEF
, DEF
, MDEF
, DEF
, CDEF
, MDEF
, CYCLE
},
1413 /* DEFW_ROW */ {DEFW
, DEFW
, DEFW
, NOACT
, NOACT
, NOACT
, NOACT
, CYCLE
},
1414 /* COMMON_ROW */ {COM
, COM
, COM
, CREF
, CREF
, BIG
, REFC
, WARNC
},
1415 /* INDR_ROW */ {IND
, IND
, IND
, MDEF
, IND
, CIND
, MIND
, CYCLE
},
1416 /* WARN_ROW */ {MWARN
, WARN
, WARN
, CWARN
, CWARN
, WARN
, CWARN
, MWARN
},
1417 /* SET_ROW */ {SET
, SET
, SET
, SET
, SET
, SET
, CYCLE
, CYCLE
}
1420 /* Most of the entries in the LINK_ACTION table are straightforward,
1421 but a few are somewhat subtle.
1423 A reference to an indirect symbol (UNDEF_ROW/indr or
1424 UNDEFW_ROW/indr) is counted as a reference both to the indirect
1425 symbol and to the symbol the indirect symbol points to.
1427 A reference to a warning symbol (UNDEF_ROW/warn or UNDEFW_ROW/warn)
1428 causes the warning to be issued.
1430 A common definition of an indirect symbol (COMMON_ROW/indr) is
1431 treated as a multiple definition error. Likewise for an indirect
1432 definition of a common symbol (INDR_ROW/com).
1434 An indirect definition of a warning (INDR_ROW/warn) does not cause
1435 the warning to be issued.
1437 If a warning is created for an indirect symbol (WARN_ROW/indr) no
1438 warning is created for the symbol the indirect symbol points to.
1440 Adding an entry to a set does not count as a reference to a set,
1441 and no warning is issued (SET_ROW/warn). */
1443 /* Return the BFD in which a hash entry has been defined, if known. */
1447 struct bfd_link_hash_entry
*h
;
1449 while (h
->type
== bfd_link_hash_warning
)
1455 case bfd_link_hash_undefined
:
1456 case bfd_link_hash_undefweak
:
1457 return h
->u
.undef
.abfd
;
1458 case bfd_link_hash_defined
:
1459 case bfd_link_hash_defweak
:
1460 return h
->u
.def
.section
->owner
;
1461 case bfd_link_hash_common
:
1462 return h
->u
.c
.p
->section
->owner
;
1467 /* Add a symbol to the global hash table.
1468 ABFD is the BFD the symbol comes from.
1469 NAME is the name of the symbol.
1470 FLAGS is the BSF_* bits associated with the symbol.
1471 SECTION is the section in which the symbol is defined; this may be
1472 bfd_und_section_ptr or bfd_com_section_ptr.
1473 VALUE is the value of the symbol, relative to the section.
1474 STRING is used for either an indirect symbol, in which case it is
1475 the name of the symbol to indirect to, or a warning symbol, in
1476 which case it is the warning string.
1477 COPY is true if NAME or STRING must be copied into locally
1478 allocated memory if they need to be saved.
1479 COLLECT is true if we should automatically collect gcc constructor
1480 or destructor names as collect2 does.
1481 HASHP, if not NULL, is a place to store the created hash table
1482 entry; if *HASHP is not NULL, the caller has already looked up
1483 the hash table entry, and stored it in *HASHP. */
1486 _bfd_generic_link_add_one_symbol (info
, abfd
, name
, flags
, section
, value
,
1487 string
, copy
, collect
, hashp
)
1488 struct bfd_link_info
*info
;
1497 struct bfd_link_hash_entry
**hashp
;
1500 struct bfd_link_hash_entry
*h
;
1503 if (bfd_is_ind_section (section
)
1504 || (flags
& BSF_INDIRECT
) != 0)
1506 else if ((flags
& BSF_WARNING
) != 0)
1508 else if ((flags
& BSF_CONSTRUCTOR
) != 0)
1510 else if (bfd_is_und_section (section
))
1512 if ((flags
& BSF_WEAK
) != 0)
1517 else if ((flags
& BSF_WEAK
) != 0)
1519 else if (bfd_is_com_section (section
))
1524 if (hashp
!= NULL
&& *hashp
!= NULL
)
1528 if (row
== UNDEF_ROW
|| row
== UNDEFW_ROW
)
1529 h
= bfd_wrapped_link_hash_lookup (abfd
, info
, name
, true, copy
, false);
1531 h
= bfd_link_hash_lookup (info
->hash
, name
, true, copy
, false);
1540 if (info
->notice_all
1541 || (info
->notice_hash
!= (struct bfd_hash_table
*) NULL
1542 && (bfd_hash_lookup (info
->notice_hash
, name
, false, false)
1543 != (struct bfd_hash_entry
*) NULL
)))
1545 if (! (*info
->callbacks
->notice
) (info
, h
->root
.string
, abfd
, section
,
1550 if (hashp
!= (struct bfd_link_hash_entry
**) NULL
)
1555 enum link_action action
;
1558 action
= link_action
[(int) row
][(int) h
->type
];
1569 /* Make a new undefined symbol. */
1570 h
->type
= bfd_link_hash_undefined
;
1571 h
->u
.undef
.abfd
= abfd
;
1572 bfd_link_add_undef (info
->hash
, h
);
1576 /* Make a new weak undefined symbol. */
1577 h
->type
= bfd_link_hash_undefweak
;
1578 h
->u
.undef
.abfd
= abfd
;
1582 /* We have found a definition for a symbol which was
1583 previously common. */
1584 BFD_ASSERT (h
->type
== bfd_link_hash_common
);
1585 if (! ((*info
->callbacks
->multiple_common
)
1586 (info
, h
->root
.string
,
1587 h
->u
.c
.p
->section
->owner
, bfd_link_hash_common
, h
->u
.c
.size
,
1588 abfd
, bfd_link_hash_defined
, (bfd_vma
) 0)))
1594 enum bfd_link_hash_type oldtype
;
1596 /* Define a symbol. */
1599 h
->type
= bfd_link_hash_defweak
;
1601 h
->type
= bfd_link_hash_defined
;
1602 h
->u
.def
.section
= section
;
1603 h
->u
.def
.value
= value
;
1605 /* If we have been asked to, we act like collect2 and
1606 identify all functions that might be global
1607 constructors and destructors and pass them up in a
1608 callback. We only do this for certain object file
1609 types, since many object file types can handle this
1611 if (collect
&& name
[0] == '_')
1615 /* A constructor or destructor name starts like this:
1616 _+GLOBAL_[_.$][ID][_.$] where the first [_.$] and
1617 the second are the same character (we accept any
1618 character there, in case a new object file format
1619 comes along with even worse naming restrictions). */
1621 #define CONS_PREFIX "GLOBAL_"
1622 #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1)
1628 && strncmp (s
, CONS_PREFIX
, CONS_PREFIX_LEN
- 1) == 0)
1632 c
= s
[CONS_PREFIX_LEN
+ 1];
1633 if ((c
== 'I' || c
== 'D')
1634 && s
[CONS_PREFIX_LEN
] == s
[CONS_PREFIX_LEN
+ 2])
1636 /* If this is a definition of a symbol which
1637 was previously weakly defined, we are in
1638 trouble. We have already added a
1639 constructor entry for the weak defined
1640 symbol, and now we are trying to add one
1641 for the new symbol. Fortunately, this case
1642 should never arise in practice. */
1643 if (oldtype
== bfd_link_hash_defweak
)
1646 if (! ((*info
->callbacks
->constructor
)
1648 c
== 'I' ? true : false,
1649 h
->root
.string
, abfd
, section
, value
)))
1659 /* We have found a common definition for a symbol. */
1660 if (h
->type
== bfd_link_hash_new
)
1661 bfd_link_add_undef (info
->hash
, h
);
1662 h
->type
= bfd_link_hash_common
;
1664 ((struct bfd_link_hash_common_entry
*)
1665 bfd_hash_allocate (&info
->hash
->table
,
1666 sizeof (struct bfd_link_hash_common_entry
)));
1667 if (h
->u
.c
.p
== NULL
)
1670 h
->u
.c
.size
= value
;
1672 /* Select a default alignment based on the size. This may
1673 be overridden by the caller. */
1677 power
= bfd_log2 (value
);
1680 h
->u
.c
.p
->alignment_power
= power
;
1683 /* The section of a common symbol is only used if the common
1684 symbol is actually allocated. It basically provides a
1685 hook for the linker script to decide which output section
1686 the common symbols should be put in. In most cases, the
1687 section of a common symbol will be bfd_com_section_ptr,
1688 the code here will choose a common symbol section named
1689 "COMMON", and the linker script will contain *(COMMON) in
1690 the appropriate place. A few targets use separate common
1691 sections for small symbols, and they require special
1693 if (section
== bfd_com_section_ptr
)
1695 h
->u
.c
.p
->section
= bfd_make_section_old_way (abfd
, "COMMON");
1696 h
->u
.c
.p
->section
->flags
= SEC_ALLOC
;
1698 else if (section
->owner
!= abfd
)
1700 h
->u
.c
.p
->section
= bfd_make_section_old_way (abfd
,
1702 h
->u
.c
.p
->section
->flags
= SEC_ALLOC
;
1705 h
->u
.c
.p
->section
= section
;
1709 /* A reference to a defined symbol. */
1710 if (h
->next
== NULL
&& info
->hash
->undefs_tail
!= h
)
1715 /* We have found a common definition for a symbol which
1716 already had a common definition. Use the maximum of the
1717 two sizes, and use the section required by the larger symbol. */
1718 BFD_ASSERT (h
->type
== bfd_link_hash_common
);
1719 if (! ((*info
->callbacks
->multiple_common
)
1720 (info
, h
->root
.string
,
1721 h
->u
.c
.p
->section
->owner
, bfd_link_hash_common
, h
->u
.c
.size
,
1722 abfd
, bfd_link_hash_common
, value
)))
1724 if (value
> h
->u
.c
.size
)
1728 h
->u
.c
.size
= value
;
1730 /* Select a default alignment based on the size. This may
1731 be overridden by the caller. */
1732 power
= bfd_log2 (value
);
1735 h
->u
.c
.p
->alignment_power
= power
;
1737 /* Some systems have special treatment for small commons,
1738 hence we want to select the section used by the larger
1739 symbol. This makes sure the symbol does not go in a
1740 small common section if it is now too large. */
1741 if (section
== bfd_com_section_ptr
)
1744 = bfd_make_section_old_way (abfd
, "COMMON");
1745 h
->u
.c
.p
->section
->flags
= SEC_ALLOC
;
1747 else if (section
->owner
!= abfd
)
1750 = bfd_make_section_old_way (abfd
, section
->name
);
1751 h
->u
.c
.p
->section
->flags
= SEC_ALLOC
;
1754 h
->u
.c
.p
->section
= section
;
1762 /* We have found a common definition for a symbol which
1763 was already defined. FIXME: It would nice if we could
1764 report the BFD which defined an indirect symbol, but we
1765 don't have anywhere to store the information. */
1766 if (h
->type
== bfd_link_hash_defined
1767 || h
->type
== bfd_link_hash_defweak
)
1768 obfd
= h
->u
.def
.section
->owner
;
1771 if (! ((*info
->callbacks
->multiple_common
)
1772 (info
, h
->root
.string
, obfd
, h
->type
, (bfd_vma
) 0,
1773 abfd
, bfd_link_hash_common
, value
)))
1779 /* Multiple indirect symbols. This is OK if they both point
1780 to the same symbol. */
1781 if (strcmp (h
->u
.i
.link
->root
.string
, string
) == 0)
1785 /* Handle a multiple definition. */
1787 asection
*msec
= NULL
;
1792 case bfd_link_hash_defined
:
1793 msec
= h
->u
.def
.section
;
1794 mval
= h
->u
.def
.value
;
1796 case bfd_link_hash_indirect
:
1797 msec
= bfd_ind_section_ptr
;
1804 /* Ignore a redefinition of an absolute symbol to the same
1805 value; it's harmless. */
1806 if (h
->type
== bfd_link_hash_defined
1807 && bfd_is_abs_section (msec
)
1808 && bfd_is_abs_section (section
)
1812 if (! ((*info
->callbacks
->multiple_definition
)
1813 (info
, h
->root
.string
, msec
->owner
, msec
, mval
, abfd
,
1820 /* Create an indirect symbol from an existing common symbol. */
1821 BFD_ASSERT (h
->type
== bfd_link_hash_common
);
1822 if (! ((*info
->callbacks
->multiple_common
)
1823 (info
, h
->root
.string
,
1824 h
->u
.c
.p
->section
->owner
, bfd_link_hash_common
, h
->u
.c
.size
,
1825 abfd
, bfd_link_hash_indirect
, (bfd_vma
) 0)))
1829 /* Create an indirect symbol. */
1831 struct bfd_link_hash_entry
*inh
;
1833 /* STRING is the name of the symbol we want to indirect
1835 inh
= bfd_wrapped_link_hash_lookup (abfd
, info
, string
, true,
1837 if (inh
== (struct bfd_link_hash_entry
*) NULL
)
1839 if (inh
->type
== bfd_link_hash_indirect
1840 && inh
->u
.i
.link
== h
)
1842 (*_bfd_error_handler
)
1843 (_("%s: indirect symbol `%s' to `%s' is a loop"),
1844 bfd_get_filename (abfd
), name
, string
);
1845 bfd_set_error (bfd_error_invalid_operation
);
1848 if (inh
->type
== bfd_link_hash_new
)
1850 inh
->type
= bfd_link_hash_undefined
;
1851 inh
->u
.undef
.abfd
= abfd
;
1852 bfd_link_add_undef (info
->hash
, inh
);
1855 /* If the indirect symbol has been referenced, we need to
1856 push the reference down to the symbol we are
1858 if (h
->type
!= bfd_link_hash_new
)
1864 h
->type
= bfd_link_hash_indirect
;
1870 /* Add an entry to a set. */
1871 if (! (*info
->callbacks
->add_to_set
) (info
, h
, BFD_RELOC_CTOR
,
1872 abfd
, section
, value
))
1877 /* Issue a warning and cycle. */
1878 if (h
->u
.i
.warning
!= NULL
)
1880 if (! (*info
->callbacks
->warning
) (info
, h
->u
.i
.warning
,
1881 h
->root
.string
, abfd
,
1885 /* Only issue a warning once. */
1886 h
->u
.i
.warning
= NULL
;
1890 /* Try again with the referenced symbol. */
1896 /* A reference to an indirect symbol. */
1897 if (h
->next
== NULL
&& info
->hash
->undefs_tail
!= h
)
1904 /* Issue a warning. */
1905 if (! (*info
->callbacks
->warning
) (info
, string
, h
->root
.string
,
1907 (asection
*) NULL
, (bfd_vma
) 0))
1912 /* Warn if this symbol has been referenced already,
1913 otherwise add a warning. A symbol has been referenced if
1914 the next field is not NULL, or it is the tail of the
1915 undefined symbol list. The REF case above helps to
1917 if (h
->next
!= NULL
|| info
->hash
->undefs_tail
== h
)
1919 if (! (*info
->callbacks
->warning
) (info
, string
, h
->root
.string
,
1928 /* Make a warning symbol. */
1930 struct bfd_link_hash_entry
*sub
;
1932 /* STRING is the warning to give. */
1933 sub
= ((struct bfd_link_hash_entry
*)
1934 ((*info
->hash
->table
.newfunc
)
1935 ((struct bfd_hash_entry
*) NULL
, &info
->hash
->table
,
1940 sub
->type
= bfd_link_hash_warning
;
1943 sub
->u
.i
.warning
= string
;
1948 w
= bfd_hash_allocate (&info
->hash
->table
,
1949 strlen (string
) + 1);
1953 sub
->u
.i
.warning
= w
;
1956 bfd_hash_replace (&info
->hash
->table
,
1957 (struct bfd_hash_entry
*) h
,
1958 (struct bfd_hash_entry
*) sub
);
1970 /* Generic final link routine. */
1973 _bfd_generic_final_link (abfd
, info
)
1975 struct bfd_link_info
*info
;
1979 struct bfd_link_order
*p
;
1981 struct generic_write_global_symbol_info wginfo
;
1983 bfd_get_outsymbols (abfd
) = (asymbol
**) NULL
;
1984 bfd_get_symcount (abfd
) = 0;
1987 /* Mark all sections which will be included in the output file. */
1988 for (o
= abfd
->sections
; o
!= NULL
; o
= o
->next
)
1989 for (p
= o
->link_order_head
; p
!= NULL
; p
= p
->next
)
1990 if (p
->type
== bfd_indirect_link_order
)
1991 p
->u
.indirect
.section
->linker_mark
= true;
1993 /* Build the output symbol table. */
1994 for (sub
= info
->input_bfds
; sub
!= (bfd
*) NULL
; sub
= sub
->link_next
)
1995 if (! _bfd_generic_link_output_symbols (abfd
, sub
, info
, &outsymalloc
))
1998 /* Accumulate the global symbols. */
2000 wginfo
.output_bfd
= abfd
;
2001 wginfo
.psymalloc
= &outsymalloc
;
2002 _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info
),
2003 _bfd_generic_link_write_global_symbol
,
2006 /* Make sure we have a trailing NULL pointer on OUTSYMBOLS. We
2007 shouldn't really need one, since we have SYMCOUNT, but some old
2008 code still expects one. */
2009 if (! generic_add_output_symbol (abfd
, &outsymalloc
, NULL
))
2012 if (info
->relocateable
)
2014 /* Allocate space for the output relocs for each section. */
2015 for (o
= abfd
->sections
;
2016 o
!= (asection
*) NULL
;
2020 for (p
= o
->link_order_head
;
2021 p
!= (struct bfd_link_order
*) NULL
;
2024 if (p
->type
== bfd_section_reloc_link_order
2025 || p
->type
== bfd_symbol_reloc_link_order
)
2027 else if (p
->type
== bfd_indirect_link_order
)
2029 asection
*input_section
;
2036 input_section
= p
->u
.indirect
.section
;
2037 input_bfd
= input_section
->owner
;
2038 relsize
= bfd_get_reloc_upper_bound (input_bfd
,
2042 relocs
= (arelent
**) bfd_malloc ((size_t) relsize
);
2043 if (!relocs
&& relsize
!= 0)
2045 symbols
= _bfd_generic_link_get_symbols (input_bfd
);
2046 reloc_count
= bfd_canonicalize_reloc (input_bfd
,
2050 if (reloc_count
< 0)
2052 BFD_ASSERT ((unsigned long) reloc_count
2053 == input_section
->reloc_count
);
2054 o
->reloc_count
+= reloc_count
;
2058 if (o
->reloc_count
> 0)
2060 o
->orelocation
= ((arelent
**)
2063 * sizeof (arelent
*))));
2064 if (!o
->orelocation
)
2066 o
->flags
|= SEC_RELOC
;
2067 /* Reset the count so that it can be used as an index
2068 when putting in the output relocs. */
2074 /* Handle all the link order information for the sections. */
2075 for (o
= abfd
->sections
;
2076 o
!= (asection
*) NULL
;
2079 for (p
= o
->link_order_head
;
2080 p
!= (struct bfd_link_order
*) NULL
;
2085 case bfd_section_reloc_link_order
:
2086 case bfd_symbol_reloc_link_order
:
2087 if (! _bfd_generic_reloc_link_order (abfd
, info
, o
, p
))
2090 case bfd_indirect_link_order
:
2091 if (! default_indirect_link_order (abfd
, info
, o
, p
, true))
2095 if (! _bfd_default_link_order (abfd
, info
, o
, p
))
2105 /* Add an output symbol to the output BFD. */
2108 generic_add_output_symbol (output_bfd
, psymalloc
, sym
)
2113 if (bfd_get_symcount (output_bfd
) >= *psymalloc
)
2117 if (*psymalloc
== 0)
2121 newsyms
= (asymbol
**) bfd_realloc (bfd_get_outsymbols (output_bfd
),
2122 *psymalloc
* sizeof (asymbol
*));
2123 if (newsyms
== (asymbol
**) NULL
)
2125 bfd_get_outsymbols (output_bfd
) = newsyms
;
2128 bfd_get_outsymbols (output_bfd
) [bfd_get_symcount (output_bfd
)] = sym
;
2130 ++ bfd_get_symcount (output_bfd
);
2135 /* Handle the symbols for an input BFD. */
2138 _bfd_generic_link_output_symbols (output_bfd
, input_bfd
, info
, psymalloc
)
2141 struct bfd_link_info
*info
;
2147 if (! generic_link_read_symbols (input_bfd
))
2150 /* Create a filename symbol if we are supposed to. */
2151 if (info
->create_object_symbols_section
!= (asection
*) NULL
)
2155 for (sec
= input_bfd
->sections
;
2156 sec
!= (asection
*) NULL
;
2159 if (sec
->output_section
== info
->create_object_symbols_section
)
2163 newsym
= bfd_make_empty_symbol (input_bfd
);
2166 newsym
->name
= input_bfd
->filename
;
2168 newsym
->flags
= BSF_LOCAL
| BSF_FILE
;
2169 newsym
->section
= sec
;
2171 if (! generic_add_output_symbol (output_bfd
, psymalloc
,
2180 /* Adjust the values of the globally visible symbols, and write out
2182 sym_ptr
= _bfd_generic_link_get_symbols (input_bfd
);
2183 sym_end
= sym_ptr
+ _bfd_generic_link_get_symcount (input_bfd
);
2184 for (; sym_ptr
< sym_end
; sym_ptr
++)
2187 struct generic_link_hash_entry
*h
;
2190 h
= (struct generic_link_hash_entry
*) NULL
;
2192 if ((sym
->flags
& (BSF_INDIRECT
2197 || bfd_is_und_section (bfd_get_section (sym
))
2198 || bfd_is_com_section (bfd_get_section (sym
))
2199 || bfd_is_ind_section (bfd_get_section (sym
)))
2201 if (sym
->udata
.p
!= NULL
)
2202 h
= (struct generic_link_hash_entry
*) sym
->udata
.p
;
2203 else if ((sym
->flags
& BSF_CONSTRUCTOR
) != 0)
2205 /* This case normally means that the main linker code
2206 deliberately ignored this constructor symbol. We
2207 should just pass it through. This will screw up if
2208 the constructor symbol is from a different,
2209 non-generic, object file format, but the case will
2210 only arise when linking with -r, which will probably
2211 fail anyhow, since there will be no way to represent
2212 the relocs in the output format being used. */
2215 else if (bfd_is_und_section (bfd_get_section (sym
)))
2216 h
= ((struct generic_link_hash_entry
*)
2217 bfd_wrapped_link_hash_lookup (output_bfd
, info
,
2218 bfd_asymbol_name (sym
),
2219 false, false, true));
2221 h
= _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info
),
2222 bfd_asymbol_name (sym
),
2223 false, false, true);
2225 if (h
!= (struct generic_link_hash_entry
*) NULL
)
2227 /* Force all references to this symbol to point to
2228 the same area in memory. It is possible that
2229 this routine will be called with a hash table
2230 other than a generic hash table, so we double
2232 if (info
->hash
->creator
== input_bfd
->xvec
)
2234 if (h
->sym
!= (asymbol
*) NULL
)
2235 *sym_ptr
= sym
= h
->sym
;
2238 switch (h
->root
.type
)
2241 case bfd_link_hash_new
:
2243 case bfd_link_hash_undefined
:
2245 case bfd_link_hash_undefweak
:
2246 sym
->flags
|= BSF_WEAK
;
2248 case bfd_link_hash_indirect
:
2249 h
= (struct generic_link_hash_entry
*) h
->root
.u
.i
.link
;
2251 case bfd_link_hash_defined
:
2252 sym
->flags
|= BSF_GLOBAL
;
2253 sym
->flags
&=~ BSF_CONSTRUCTOR
;
2254 sym
->value
= h
->root
.u
.def
.value
;
2255 sym
->section
= h
->root
.u
.def
.section
;
2257 case bfd_link_hash_defweak
:
2258 sym
->flags
|= BSF_WEAK
;
2259 sym
->flags
&=~ BSF_CONSTRUCTOR
;
2260 sym
->value
= h
->root
.u
.def
.value
;
2261 sym
->section
= h
->root
.u
.def
.section
;
2263 case bfd_link_hash_common
:
2264 sym
->value
= h
->root
.u
.c
.size
;
2265 sym
->flags
|= BSF_GLOBAL
;
2266 if (! bfd_is_com_section (sym
->section
))
2268 BFD_ASSERT (bfd_is_und_section (sym
->section
));
2269 sym
->section
= bfd_com_section_ptr
;
2271 /* We do not set the section of the symbol to
2272 h->root.u.c.p->section. That value was saved so
2273 that we would know where to allocate the symbol
2274 if it was defined. In this case the type is
2275 still bfd_link_hash_common, so we did not define
2276 it, so we do not want to use that section. */
2282 /* This switch is straight from the old code in
2283 write_file_locals in ldsym.c. */
2284 if (info
->strip
== strip_all
2285 || (info
->strip
== strip_some
2286 && (bfd_hash_lookup (info
->keep_hash
, bfd_asymbol_name (sym
),
2288 == (struct bfd_hash_entry
*) NULL
)))
2290 else if ((sym
->flags
& (BSF_GLOBAL
| BSF_WEAK
)) != 0)
2292 /* If this symbol is marked as occurring now, rather
2293 than at the end, output it now. This is used for
2294 COFF C_EXT FCN symbols. FIXME: There must be a
2296 if (bfd_asymbol_bfd (sym
) == input_bfd
2297 && (sym
->flags
& BSF_NOT_AT_END
) != 0)
2302 else if (bfd_is_ind_section (sym
->section
))
2304 else if ((sym
->flags
& BSF_DEBUGGING
) != 0)
2306 if (info
->strip
== strip_none
)
2311 else if (bfd_is_und_section (sym
->section
)
2312 || bfd_is_com_section (sym
->section
))
2314 else if ((sym
->flags
& BSF_LOCAL
) != 0)
2316 if ((sym
->flags
& BSF_WARNING
) != 0)
2320 switch (info
->discard
)
2326 case discard_sec_merge
:
2328 if (info
->relocateable
2329 || ! (sym
->section
->flags
& SEC_MERGE
))
2333 if (bfd_is_local_label (input_bfd
, sym
))
2344 else if ((sym
->flags
& BSF_CONSTRUCTOR
))
2346 if (info
->strip
!= strip_all
)
2354 /* If this symbol is in a section which is not being included
2355 in the output file, then we don't want to output the symbol.
2357 Gross. .bss and similar sections won't have the linker_mark
2359 if ((sym
->section
->flags
& SEC_HAS_CONTENTS
) != 0
2360 && sym
->section
->linker_mark
== false)
2365 if (! generic_add_output_symbol (output_bfd
, psymalloc
, sym
))
2367 if (h
!= (struct generic_link_hash_entry
*) NULL
)
2375 /* Set the section and value of a generic BFD symbol based on a linker
2376 hash table entry. */
2379 set_symbol_from_hash (sym
, h
)
2381 struct bfd_link_hash_entry
*h
;
2388 case bfd_link_hash_new
:
2389 /* This can happen when a constructor symbol is seen but we are
2390 not building constructors. */
2391 if (sym
->section
!= NULL
)
2393 BFD_ASSERT ((sym
->flags
& BSF_CONSTRUCTOR
) != 0);
2397 sym
->flags
|= BSF_CONSTRUCTOR
;
2398 sym
->section
= bfd_abs_section_ptr
;
2402 case bfd_link_hash_undefined
:
2403 sym
->section
= bfd_und_section_ptr
;
2406 case bfd_link_hash_undefweak
:
2407 sym
->section
= bfd_und_section_ptr
;
2409 sym
->flags
|= BSF_WEAK
;
2411 case bfd_link_hash_defined
:
2412 sym
->section
= h
->u
.def
.section
;
2413 sym
->value
= h
->u
.def
.value
;
2415 case bfd_link_hash_defweak
:
2416 sym
->flags
|= BSF_WEAK
;
2417 sym
->section
= h
->u
.def
.section
;
2418 sym
->value
= h
->u
.def
.value
;
2420 case bfd_link_hash_common
:
2421 sym
->value
= h
->u
.c
.size
;
2422 if (sym
->section
== NULL
)
2423 sym
->section
= bfd_com_section_ptr
;
2424 else if (! bfd_is_com_section (sym
->section
))
2426 BFD_ASSERT (bfd_is_und_section (sym
->section
));
2427 sym
->section
= bfd_com_section_ptr
;
2429 /* Do not set the section; see _bfd_generic_link_output_symbols. */
2431 case bfd_link_hash_indirect
:
2432 case bfd_link_hash_warning
:
2433 /* FIXME: What should we do here? */
2438 /* Write out a global symbol, if it hasn't already been written out.
2439 This is called for each symbol in the hash table. */
2442 _bfd_generic_link_write_global_symbol (h
, data
)
2443 struct generic_link_hash_entry
*h
;
2446 struct generic_write_global_symbol_info
*wginfo
=
2447 (struct generic_write_global_symbol_info
*) data
;
2455 if (wginfo
->info
->strip
== strip_all
2456 || (wginfo
->info
->strip
== strip_some
2457 && bfd_hash_lookup (wginfo
->info
->keep_hash
, h
->root
.root
.string
,
2458 false, false) == NULL
))
2461 if (h
->sym
!= (asymbol
*) NULL
)
2465 sym
= bfd_make_empty_symbol (wginfo
->output_bfd
);
2468 sym
->name
= h
->root
.root
.string
;
2472 set_symbol_from_hash (sym
, &h
->root
);
2474 sym
->flags
|= BSF_GLOBAL
;
2476 if (! generic_add_output_symbol (wginfo
->output_bfd
, wginfo
->psymalloc
,
2479 /* FIXME: No way to return failure. */
2486 /* Create a relocation. */
2489 _bfd_generic_reloc_link_order (abfd
, info
, sec
, link_order
)
2491 struct bfd_link_info
*info
;
2493 struct bfd_link_order
*link_order
;
2497 if (! info
->relocateable
)
2499 if (sec
->orelocation
== (arelent
**) NULL
)
2502 r
= (arelent
*) bfd_alloc (abfd
, sizeof (arelent
));
2503 if (r
== (arelent
*) NULL
)
2506 r
->address
= link_order
->offset
;
2507 r
->howto
= bfd_reloc_type_lookup (abfd
, link_order
->u
.reloc
.p
->reloc
);
2510 bfd_set_error (bfd_error_bad_value
);
2514 /* Get the symbol to use for the relocation. */
2515 if (link_order
->type
== bfd_section_reloc_link_order
)
2516 r
->sym_ptr_ptr
= link_order
->u
.reloc
.p
->u
.section
->symbol_ptr_ptr
;
2519 struct generic_link_hash_entry
*h
;
2521 h
= ((struct generic_link_hash_entry
*)
2522 bfd_wrapped_link_hash_lookup (abfd
, info
,
2523 link_order
->u
.reloc
.p
->u
.name
,
2524 false, false, true));
2525 if (h
== (struct generic_link_hash_entry
*) NULL
2528 if (! ((*info
->callbacks
->unattached_reloc
)
2529 (info
, link_order
->u
.reloc
.p
->u
.name
,
2530 (bfd
*) NULL
, (asection
*) NULL
, (bfd_vma
) 0)))
2532 bfd_set_error (bfd_error_bad_value
);
2535 r
->sym_ptr_ptr
= &h
->sym
;
2538 /* If this is an inplace reloc, write the addend to the object file.
2539 Otherwise, store it in the reloc addend. */
2540 if (! r
->howto
->partial_inplace
)
2541 r
->addend
= link_order
->u
.reloc
.p
->addend
;
2545 bfd_reloc_status_type rstat
;
2549 size
= bfd_get_reloc_size (r
->howto
);
2550 buf
= (bfd_byte
*) bfd_zmalloc (size
);
2551 if (buf
== (bfd_byte
*) NULL
)
2553 rstat
= _bfd_relocate_contents (r
->howto
, abfd
,
2554 link_order
->u
.reloc
.p
->addend
, buf
);
2560 case bfd_reloc_outofrange
:
2562 case bfd_reloc_overflow
:
2563 if (! ((*info
->callbacks
->reloc_overflow
)
2565 (link_order
->type
== bfd_section_reloc_link_order
2566 ? bfd_section_name (abfd
, link_order
->u
.reloc
.p
->u
.section
)
2567 : link_order
->u
.reloc
.p
->u
.name
),
2568 r
->howto
->name
, link_order
->u
.reloc
.p
->addend
,
2569 (bfd
*) NULL
, (asection
*) NULL
, (bfd_vma
) 0)))
2576 ok
= bfd_set_section_contents (abfd
, sec
, (PTR
) buf
,
2578 (link_order
->offset
*
2579 bfd_octets_per_byte (abfd
)), size
);
2587 sec
->orelocation
[sec
->reloc_count
] = r
;
2593 /* Allocate a new link_order for a section. */
2595 struct bfd_link_order
*
2596 bfd_new_link_order (abfd
, section
)
2600 struct bfd_link_order
*new;
2602 new = ((struct bfd_link_order
*)
2603 bfd_alloc (abfd
, sizeof (struct bfd_link_order
)));
2607 new->type
= bfd_undefined_link_order
;
2610 new->next
= (struct bfd_link_order
*) NULL
;
2612 if (section
->link_order_tail
!= (struct bfd_link_order
*) NULL
)
2613 section
->link_order_tail
->next
= new;
2615 section
->link_order_head
= new;
2616 section
->link_order_tail
= new;
2621 /* Default link order processing routine. Note that we can not handle
2622 the reloc_link_order types here, since they depend upon the details
2623 of how the particular backends generates relocs. */
2626 _bfd_default_link_order (abfd
, info
, sec
, link_order
)
2628 struct bfd_link_info
*info
;
2630 struct bfd_link_order
*link_order
;
2632 switch (link_order
->type
)
2634 case bfd_undefined_link_order
:
2635 case bfd_section_reloc_link_order
:
2636 case bfd_symbol_reloc_link_order
:
2639 case bfd_indirect_link_order
:
2640 return default_indirect_link_order (abfd
, info
, sec
, link_order
,
2642 case bfd_fill_link_order
:
2643 return default_fill_link_order (abfd
, info
, sec
, link_order
);
2644 case bfd_data_link_order
:
2645 return bfd_set_section_contents (abfd
, sec
,
2646 (PTR
) link_order
->u
.data
.contents
,
2648 (link_order
->offset
*
2649 bfd_octets_per_byte (abfd
)),
2654 /* Default routine to handle a bfd_fill_link_order. */
2657 default_fill_link_order (abfd
, info
, sec
, link_order
)
2659 struct bfd_link_info
*info ATTRIBUTE_UNUSED
;
2661 struct bfd_link_order
*link_order
;
2664 unsigned char *space
;
2670 BFD_ASSERT ((sec
->flags
& SEC_HAS_CONTENTS
) != 0);
2672 size
= (size_t) link_order
->size
;
2676 space
= (unsigned char *) bfd_malloc (size
);
2680 fill
= link_order
->u
.fill
.value
;
2681 for (i
= 0; i
< size
; i
+= 4)
2682 space
[i
] = fill
>> 24;
2683 for (i
= 1; i
< size
; i
+= 4)
2684 space
[i
] = fill
>> 16;
2685 for (i
= 2; i
< size
; i
+= 4)
2686 space
[i
] = fill
>> 8;
2687 for (i
= 3; i
< size
; i
+= 4)
2690 loc
= (file_ptr
) (link_order
->offset
* bfd_octets_per_byte (abfd
));
2691 result
= bfd_set_section_contents (abfd
, sec
, space
, loc
, link_order
->size
);
2697 /* Default routine to handle a bfd_indirect_link_order. */
2700 default_indirect_link_order (output_bfd
, info
, output_section
, link_order
,
2703 struct bfd_link_info
*info
;
2704 asection
*output_section
;
2705 struct bfd_link_order
*link_order
;
2706 boolean generic_linker
;
2708 asection
*input_section
;
2710 bfd_byte
*contents
= NULL
;
2711 bfd_byte
*new_contents
;
2713 BFD_ASSERT ((output_section
->flags
& SEC_HAS_CONTENTS
) != 0);
2715 if (link_order
->size
== 0)
2718 input_section
= link_order
->u
.indirect
.section
;
2719 input_bfd
= input_section
->owner
;
2721 BFD_ASSERT (input_section
->output_section
== output_section
);
2722 BFD_ASSERT (input_section
->output_offset
== link_order
->offset
);
2723 BFD_ASSERT (input_section
->_cooked_size
== link_order
->size
);
2725 if (info
->relocateable
2726 && input_section
->reloc_count
> 0
2727 && output_section
->orelocation
== (arelent
**) NULL
)
2729 /* Space has not been allocated for the output relocations.
2730 This can happen when we are called by a specific backend
2731 because somebody is attempting to link together different
2732 types of object files. Handling this case correctly is
2733 difficult, and sometimes impossible. */
2734 (*_bfd_error_handler
)
2735 (_("Attempt to do relocateable link with %s input and %s output"),
2736 bfd_get_target (input_bfd
), bfd_get_target (output_bfd
));
2737 bfd_set_error (bfd_error_wrong_format
);
2741 if (! generic_linker
)
2746 /* Get the canonical symbols. The generic linker will always
2747 have retrieved them by this point, but we are being called by
2748 a specific linker, presumably because we are linking
2749 different types of object files together. */
2750 if (! generic_link_read_symbols (input_bfd
))
2753 /* Since we have been called by a specific linker, rather than
2754 the generic linker, the values of the symbols will not be
2755 right. They will be the values as seen in the input file,
2756 not the values of the final link. We need to fix them up
2757 before we can relocate the section. */
2758 sympp
= _bfd_generic_link_get_symbols (input_bfd
);
2759 symppend
= sympp
+ _bfd_generic_link_get_symcount (input_bfd
);
2760 for (; sympp
< symppend
; sympp
++)
2763 struct bfd_link_hash_entry
*h
;
2767 if ((sym
->flags
& (BSF_INDIRECT
2772 || bfd_is_und_section (bfd_get_section (sym
))
2773 || bfd_is_com_section (bfd_get_section (sym
))
2774 || bfd_is_ind_section (bfd_get_section (sym
)))
2776 /* sym->udata may have been set by
2777 generic_link_add_symbol_list. */
2778 if (sym
->udata
.p
!= NULL
)
2779 h
= (struct bfd_link_hash_entry
*) sym
->udata
.p
;
2780 else if (bfd_is_und_section (bfd_get_section (sym
)))
2781 h
= bfd_wrapped_link_hash_lookup (output_bfd
, info
,
2782 bfd_asymbol_name (sym
),
2783 false, false, true);
2785 h
= bfd_link_hash_lookup (info
->hash
,
2786 bfd_asymbol_name (sym
),
2787 false, false, true);
2789 set_symbol_from_hash (sym
, h
);
2794 /* Get and relocate the section contents. */
2795 contents
= ((bfd_byte
*)
2796 bfd_malloc (bfd_section_size (input_bfd
, input_section
)));
2797 if (contents
== NULL
&& bfd_section_size (input_bfd
, input_section
) != 0)
2799 new_contents
= (bfd_get_relocated_section_contents
2800 (output_bfd
, info
, link_order
, contents
, info
->relocateable
,
2801 _bfd_generic_link_get_symbols (input_bfd
)));
2805 /* Output the section contents. */
2806 if (! bfd_set_section_contents (output_bfd
, output_section
,
2809 (link_order
->offset
*
2810 bfd_octets_per_byte (output_bfd
)),
2814 if (contents
!= NULL
)
2819 if (contents
!= NULL
)
2824 /* A little routine to count the number of relocs in a link_order
2828 _bfd_count_link_order_relocs (link_order
)
2829 struct bfd_link_order
*link_order
;
2831 register unsigned int c
;
2832 register struct bfd_link_order
*l
;
2835 for (l
= link_order
; l
!= (struct bfd_link_order
*) NULL
; l
= l
->next
)
2837 if (l
->type
== bfd_section_reloc_link_order
2838 || l
->type
== bfd_symbol_reloc_link_order
)
2847 bfd_link_split_section
2850 boolean bfd_link_split_section(bfd *abfd, asection *sec);
2853 Return nonzero if @var{sec} should be split during a
2854 reloceatable or final link.
2856 .#define bfd_link_split_section(abfd, sec) \
2857 . BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec))
2863 _bfd_generic_link_split_section (abfd
, sec
)
2864 bfd
*abfd ATTRIBUTE_UNUSED
;
2865 asection
*sec ATTRIBUTE_UNUSED
;