xref: /NextBSD/contrib/binutils/bfd/linker.c (revision eb1a5f8de9f7ea602c373a710f531abbf81141c4)
1 /* linker.c -- BFD linker routines
2    Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
3    2003, 2004, 2005, 2006, 2007
4    Free Software Foundation, Inc.
5    Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support
6 
7    This file is part of BFD, the Binary File Descriptor library.
8 
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 2 of the License, or
12    (at your option) any later version.
13 
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18 
19    You should have received a copy of the GNU General Public License
20    along with this program; if not, write to the Free Software
21    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
22 
23 #include "sysdep.h"
24 #include "bfd.h"
25 #include "libbfd.h"
26 #include "bfdlink.h"
27 #include "genlink.h"
28 
29 /*
30 SECTION
31 	Linker Functions
32 
33 @cindex Linker
34 	The linker uses three special entry points in the BFD target
35 	vector.  It is not necessary to write special routines for
36 	these entry points when creating a new BFD back end, since
37 	generic versions are provided.  However, writing them can
38 	speed up linking and make it use significantly less runtime
39 	memory.
40 
41 	The first routine creates a hash table used by the other
42 	routines.  The second routine adds the symbols from an object
43 	file to the hash table.  The third routine takes all the
44 	object files and links them together to create the output
45 	file.  These routines are designed so that the linker proper
46 	does not need to know anything about the symbols in the object
47 	files that it is linking.  The linker merely arranges the
48 	sections as directed by the linker script and lets BFD handle
49 	the details of symbols and relocs.
50 
51 	The second routine and third routines are passed a pointer to
52 	a <<struct bfd_link_info>> structure (defined in
53 	<<bfdlink.h>>) which holds information relevant to the link,
54 	including the linker hash table (which was created by the
55 	first routine) and a set of callback functions to the linker
56 	proper.
57 
58 	The generic linker routines are in <<linker.c>>, and use the
59 	header file <<genlink.h>>.  As of this writing, the only back
60 	ends which have implemented versions of these routines are
61 	a.out (in <<aoutx.h>>) and ECOFF (in <<ecoff.c>>).  The a.out
62 	routines are used as examples throughout this section.
63 
64 @menu
65 @* Creating a Linker Hash Table::
66 @* Adding Symbols to the Hash Table::
67 @* Performing the Final Link::
68 @end menu
69 
70 INODE
71 Creating a Linker Hash Table, Adding Symbols to the Hash Table, Linker Functions, Linker Functions
72 SUBSECTION
73 	Creating a linker hash table
74 
75 @cindex _bfd_link_hash_table_create in target vector
76 @cindex target vector (_bfd_link_hash_table_create)
77 	The linker routines must create a hash table, which must be
78 	derived from <<struct bfd_link_hash_table>> described in
79 	<<bfdlink.c>>.  @xref{Hash Tables}, for information on how to
80 	create a derived hash table.  This entry point is called using
81 	the target vector of the linker output file.
82 
83 	The <<_bfd_link_hash_table_create>> entry point must allocate
84 	and initialize an instance of the desired hash table.  If the
85 	back end does not require any additional information to be
86 	stored with the entries in the hash table, the entry point may
87 	simply create a <<struct bfd_link_hash_table>>.  Most likely,
88 	however, some additional information will be needed.
89 
90 	For example, with each entry in the hash table the a.out
91 	linker keeps the index the symbol has in the final output file
92 	(this index number is used so that when doing a relocatable
93 	link the symbol index used in the output file can be quickly
94 	filled in when copying over a reloc).  The a.out linker code
95 	defines the required structures and functions for a hash table
96 	derived from <<struct bfd_link_hash_table>>.  The a.out linker
97 	hash table is created by the function
98 	<<NAME(aout,link_hash_table_create)>>; it simply allocates
99 	space for the hash table, initializes it, and returns a
100 	pointer to it.
101 
102 	When writing the linker routines for a new back end, you will
103 	generally not know exactly which fields will be required until
104 	you have finished.  You should simply create a new hash table
105 	which defines no additional fields, and then simply add fields
106 	as they become necessary.
107 
108 INODE
109 Adding Symbols to the Hash Table, Performing the Final Link, Creating a Linker Hash Table, Linker Functions
110 SUBSECTION
111 	Adding symbols to the hash table
112 
113 @cindex _bfd_link_add_symbols in target vector
114 @cindex target vector (_bfd_link_add_symbols)
115 	The linker proper will call the <<_bfd_link_add_symbols>>
116 	entry point for each object file or archive which is to be
117 	linked (typically these are the files named on the command
118 	line, but some may also come from the linker script).  The
119 	entry point is responsible for examining the file.  For an
120 	object file, BFD must add any relevant symbol information to
121 	the hash table.  For an archive, BFD must determine which
122 	elements of the archive should be used and adding them to the
123 	link.
124 
125 	The a.out version of this entry point is
126 	<<NAME(aout,link_add_symbols)>>.
127 
128 @menu
129 @* Differing file formats::
130 @* Adding symbols from an object file::
131 @* Adding symbols from an archive::
132 @end menu
133 
134 INODE
135 Differing file formats, Adding symbols from an object file, Adding Symbols to the Hash Table, Adding Symbols to the Hash Table
136 SUBSUBSECTION
137 	Differing file formats
138 
139 	Normally all the files involved in a link will be of the same
140 	format, but it is also possible to link together different
141 	format object files, and the back end must support that.  The
142 	<<_bfd_link_add_symbols>> entry point is called via the target
143 	vector of the file to be added.  This has an important
144 	consequence: the function may not assume that the hash table
145 	is the type created by the corresponding
146 	<<_bfd_link_hash_table_create>> vector.  All the
147 	<<_bfd_link_add_symbols>> function can assume about the hash
148 	table is that it is derived from <<struct
149 	bfd_link_hash_table>>.
150 
151 	Sometimes the <<_bfd_link_add_symbols>> function must store
152 	some information in the hash table entry to be used by the
153 	<<_bfd_final_link>> function.  In such a case the <<creator>>
154 	field of the hash table must be checked to make sure that the
155 	hash table was created by an object file of the same format.
156 
157 	The <<_bfd_final_link>> routine must be prepared to handle a
158 	hash entry without any extra information added by the
159 	<<_bfd_link_add_symbols>> function.  A hash entry without
160 	extra information will also occur when the linker script
161 	directs the linker to create a symbol.  Note that, regardless
162 	of how a hash table entry is added, all the fields will be
163 	initialized to some sort of null value by the hash table entry
164 	initialization function.
165 
166 	See <<ecoff_link_add_externals>> for an example of how to
167 	check the <<creator>> field before saving information (in this
168 	case, the ECOFF external symbol debugging information) in a
169 	hash table entry.
170 
171 INODE
172 Adding symbols from an object file, Adding symbols from an archive, Differing file formats, Adding Symbols to the Hash Table
173 SUBSUBSECTION
174 	Adding symbols from an object file
175 
176 	When the <<_bfd_link_add_symbols>> routine is passed an object
177 	file, it must add all externally visible symbols in that
178 	object file to the hash table.  The actual work of adding the
179 	symbol to the hash table is normally handled by the function
180 	<<_bfd_generic_link_add_one_symbol>>.  The
181 	<<_bfd_link_add_symbols>> routine is responsible for reading
182 	all the symbols from the object file and passing the correct
183 	information to <<_bfd_generic_link_add_one_symbol>>.
184 
185 	The <<_bfd_link_add_symbols>> routine should not use
186 	<<bfd_canonicalize_symtab>> to read the symbols.  The point of
187 	providing this routine is to avoid the overhead of converting
188 	the symbols into generic <<asymbol>> structures.
189 
190 @findex _bfd_generic_link_add_one_symbol
191 	<<_bfd_generic_link_add_one_symbol>> handles the details of
192 	combining common symbols, warning about multiple definitions,
193 	and so forth.  It takes arguments which describe the symbol to
194 	add, notably symbol flags, a section, and an offset.  The
195 	symbol flags include such things as <<BSF_WEAK>> or
196 	<<BSF_INDIRECT>>.  The section is a section in the object
197 	file, or something like <<bfd_und_section_ptr>> for an undefined
198 	symbol or <<bfd_com_section_ptr>> for a common symbol.
199 
200 	If the <<_bfd_final_link>> routine is also going to need to
201 	read the symbol information, the <<_bfd_link_add_symbols>>
202 	routine should save it somewhere attached to the object file
203 	BFD.  However, the information should only be saved if the
204 	<<keep_memory>> field of the <<info>> argument is TRUE, so
205 	that the <<-no-keep-memory>> linker switch is effective.
206 
207 	The a.out function which adds symbols from an object file is
208 	<<aout_link_add_object_symbols>>, and most of the interesting
209 	work is in <<aout_link_add_symbols>>.  The latter saves
210 	pointers to the hash tables entries created by
211 	<<_bfd_generic_link_add_one_symbol>> indexed by symbol number,
212 	so that the <<_bfd_final_link>> routine does not have to call
213 	the hash table lookup routine to locate the entry.
214 
215 INODE
216 Adding symbols from an archive, , Adding symbols from an object file, Adding Symbols to the Hash Table
217 SUBSUBSECTION
218 	Adding symbols from an archive
219 
220 	When the <<_bfd_link_add_symbols>> routine is passed an
221 	archive, it must look through the symbols defined by the
222 	archive and decide which elements of the archive should be
223 	included in the link.  For each such element it must call the
224 	<<add_archive_element>> linker callback, and it must add the
225 	symbols from the object file to the linker hash table.
226 
227 @findex _bfd_generic_link_add_archive_symbols
228 	In most cases the work of looking through the symbols in the
229 	archive should be done by the
230 	<<_bfd_generic_link_add_archive_symbols>> function.  This
231 	function builds a hash table from the archive symbol table and
232 	looks through the list of undefined symbols to see which
233 	elements should be included.
234 	<<_bfd_generic_link_add_archive_symbols>> is passed a function
235 	to call to make the final decision about adding an archive
236 	element to the link and to do the actual work of adding the
237 	symbols to the linker hash table.
238 
239 	The function passed to
240 	<<_bfd_generic_link_add_archive_symbols>> must read the
241 	symbols of the archive element and decide whether the archive
242 	element should be included in the link.  If the element is to
243 	be included, the <<add_archive_element>> linker callback
244 	routine must be called with the element as an argument, and
245 	the elements symbols must be added to the linker hash table
246 	just as though the element had itself been passed to the
247 	<<_bfd_link_add_symbols>> function.
248 
249 	When the a.out <<_bfd_link_add_symbols>> function receives an
250 	archive, it calls <<_bfd_generic_link_add_archive_symbols>>
251 	passing <<aout_link_check_archive_element>> as the function
252 	argument. <<aout_link_check_archive_element>> calls
253 	<<aout_link_check_ar_symbols>>.  If the latter decides to add
254 	the element (an element is only added if it provides a real,
255 	non-common, definition for a previously undefined or common
256 	symbol) it calls the <<add_archive_element>> callback and then
257 	<<aout_link_check_archive_element>> calls
258 	<<aout_link_add_symbols>> to actually add the symbols to the
259 	linker hash table.
260 
261 	The ECOFF back end is unusual in that it does not normally
262 	call <<_bfd_generic_link_add_archive_symbols>>, because ECOFF
263 	archives already contain a hash table of symbols.  The ECOFF
264 	back end searches the archive itself to avoid the overhead of
265 	creating a new hash table.
266 
267 INODE
268 Performing the Final Link, , Adding Symbols to the Hash Table, Linker Functions
269 SUBSECTION
270 	Performing the final link
271 
272 @cindex _bfd_link_final_link in target vector
273 @cindex target vector (_bfd_final_link)
274 	When all the input files have been processed, the linker calls
275 	the <<_bfd_final_link>> entry point of the output BFD.  This
276 	routine is responsible for producing the final output file,
277 	which has several aspects.  It must relocate the contents of
278 	the input sections and copy the data into the output sections.
279 	It must build an output symbol table including any local
280 	symbols from the input files and the global symbols from the
281 	hash table.  When producing relocatable output, it must
282 	modify the input relocs and write them into the output file.
283 	There may also be object format dependent work to be done.
284 
285 	The linker will also call the <<write_object_contents>> entry
286 	point when the BFD is closed.  The two entry points must work
287 	together in order to produce the correct output file.
288 
289 	The details of how this works are inevitably dependent upon
290 	the specific object file format.  The a.out
291 	<<_bfd_final_link>> routine is <<NAME(aout,final_link)>>.
292 
293 @menu
294 @* Information provided by the linker::
295 @* Relocating the section contents::
296 @* Writing the symbol table::
297 @end menu
298 
299 INODE
300 Information provided by the linker, Relocating the section contents, Performing the Final Link, Performing the Final Link
301 SUBSUBSECTION
302 	Information provided by the linker
303 
304 	Before the linker calls the <<_bfd_final_link>> entry point,
305 	it sets up some data structures for the function to use.
306 
307 	The <<input_bfds>> field of the <<bfd_link_info>> structure
308 	will point to a list of all the input files included in the
309 	link.  These files are linked through the <<link_next>> field
310 	of the <<bfd>> structure.
311 
312 	Each section in the output file will have a list of
313 	<<link_order>> structures attached to the <<map_head.link_order>>
314 	field (the <<link_order>> structure is defined in
315 	<<bfdlink.h>>).  These structures describe how to create the
316 	contents of the output section in terms of the contents of
317 	various input sections, fill constants, and, eventually, other
318 	types of information.  They also describe relocs that must be
319 	created by the BFD backend, but do not correspond to any input
320 	file; this is used to support -Ur, which builds constructors
321 	while generating a relocatable object file.
322 
323 INODE
324 Relocating the section contents, Writing the symbol table, Information provided by the linker, Performing the Final Link
325 SUBSUBSECTION
326 	Relocating the section contents
327 
328 	The <<_bfd_final_link>> function should look through the
329 	<<link_order>> structures attached to each section of the
330 	output file.  Each <<link_order>> structure should either be
331 	handled specially, or it should be passed to the function
332 	<<_bfd_default_link_order>> which will do the right thing
333 	(<<_bfd_default_link_order>> is defined in <<linker.c>>).
334 
335 	For efficiency, a <<link_order>> of type
336 	<<bfd_indirect_link_order>> whose associated section belongs
337 	to a BFD of the same format as the output BFD must be handled
338 	specially.  This type of <<link_order>> describes part of an
339 	output section in terms of a section belonging to one of the
340 	input files.  The <<_bfd_final_link>> function should read the
341 	contents of the section and any associated relocs, apply the
342 	relocs to the section contents, and write out the modified
343 	section contents.  If performing a relocatable link, the
344 	relocs themselves must also be modified and written out.
345 
346 @findex _bfd_relocate_contents
347 @findex _bfd_final_link_relocate
348 	The functions <<_bfd_relocate_contents>> and
349 	<<_bfd_final_link_relocate>> provide some general support for
350 	performing the actual relocations, notably overflow checking.
351 	Their arguments include information about the symbol the
352 	relocation is against and a <<reloc_howto_type>> argument
353 	which describes the relocation to perform.  These functions
354 	are defined in <<reloc.c>>.
355 
356 	The a.out function which handles reading, relocating, and
357 	writing section contents is <<aout_link_input_section>>.  The
358 	actual relocation is done in <<aout_link_input_section_std>>
359 	and <<aout_link_input_section_ext>>.
360 
361 INODE
362 Writing the symbol table, , Relocating the section contents, Performing the Final Link
363 SUBSUBSECTION
364 	Writing the symbol table
365 
366 	The <<_bfd_final_link>> function must gather all the symbols
367 	in the input files and write them out.  It must also write out
368 	all the symbols in the global hash table.  This must be
369 	controlled by the <<strip>> and <<discard>> fields of the
370 	<<bfd_link_info>> structure.
371 
372 	The local symbols of the input files will not have been
373 	entered into the linker hash table.  The <<_bfd_final_link>>
374 	routine must consider each input file and include the symbols
375 	in the output file.  It may be convenient to do this when
376 	looking through the <<link_order>> structures, or it may be
377 	done by stepping through the <<input_bfds>> list.
378 
379 	The <<_bfd_final_link>> routine must also traverse the global
380 	hash table to gather all the externally visible symbols.  It
381 	is possible that most of the externally visible symbols may be
382 	written out when considering the symbols of each input file,
383 	but it is still necessary to traverse the hash table since the
384 	linker script may have defined some symbols that are not in
385 	any of the input files.
386 
387 	The <<strip>> field of the <<bfd_link_info>> structure
388 	controls which symbols are written out.  The possible values
389 	are listed in <<bfdlink.h>>.  If the value is <<strip_some>>,
390 	then the <<keep_hash>> field of the <<bfd_link_info>>
391 	structure is a hash table of symbols to keep; each symbol
392 	should be looked up in this hash table, and only symbols which
393 	are present should be included in the output file.
394 
395 	If the <<strip>> field of the <<bfd_link_info>> structure
396 	permits local symbols to be written out, the <<discard>> field
397 	is used to further controls which local symbols are included
398 	in the output file.  If the value is <<discard_l>>, then all
399 	local symbols which begin with a certain prefix are discarded;
400 	this is controlled by the <<bfd_is_local_label_name>> entry point.
401 
402 	The a.out backend handles symbols by calling
403 	<<aout_link_write_symbols>> on each input BFD and then
404 	traversing the global hash table with the function
405 	<<aout_link_write_other_symbol>>.  It builds a string table
406 	while writing out the symbols, which is written to the output
407 	file at the end of <<NAME(aout,final_link)>>.
408 */
409 
410 static bfd_boolean generic_link_add_object_symbols
411   (bfd *, struct bfd_link_info *, bfd_boolean collect);
412 static bfd_boolean generic_link_add_symbols
413   (bfd *, struct bfd_link_info *, bfd_boolean);
414 static bfd_boolean generic_link_check_archive_element_no_collect
415   (bfd *, struct bfd_link_info *, bfd_boolean *);
416 static bfd_boolean generic_link_check_archive_element_collect
417   (bfd *, struct bfd_link_info *, bfd_boolean *);
418 static bfd_boolean generic_link_check_archive_element
419   (bfd *, struct bfd_link_info *, bfd_boolean *, bfd_boolean);
420 static bfd_boolean generic_link_add_symbol_list
421   (bfd *, struct bfd_link_info *, bfd_size_type count, asymbol **,
422    bfd_boolean);
423 static bfd_boolean generic_add_output_symbol
424   (bfd *, size_t *psymalloc, asymbol *);
425 static bfd_boolean default_data_link_order
426   (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *);
427 static bfd_boolean default_indirect_link_order
428   (bfd *, struct bfd_link_info *, asection *, struct bfd_link_order *,
429    bfd_boolean);
430 
431 /* The link hash table structure is defined in bfdlink.h.  It provides
432    a base hash table which the backend specific hash tables are built
433    upon.  */
434 
435 /* Routine to create an entry in the link hash table.  */
436 
437 struct bfd_hash_entry *
_bfd_link_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)438 _bfd_link_hash_newfunc (struct bfd_hash_entry *entry,
439 			struct bfd_hash_table *table,
440 			const char *string)
441 {
442   /* Allocate the structure if it has not already been allocated by a
443      subclass.  */
444   if (entry == NULL)
445     {
446       entry = bfd_hash_allocate (table, sizeof (struct bfd_link_hash_entry));
447       if (entry == NULL)
448 	return entry;
449     }
450 
451   /* Call the allocation method of the superclass.  */
452   entry = bfd_hash_newfunc (entry, table, string);
453   if (entry)
454     {
455       struct bfd_link_hash_entry *h = (struct bfd_link_hash_entry *) entry;
456 
457       /* Initialize the local fields.  */
458       h->type = bfd_link_hash_new;
459       memset (&h->u.undef.next, 0,
460 	      (sizeof (struct bfd_link_hash_entry)
461 	       - offsetof (struct bfd_link_hash_entry, u.undef.next)));
462     }
463 
464   return entry;
465 }
466 
467 /* Initialize a link hash table.  The BFD argument is the one
468    responsible for creating this table.  */
469 
470 bfd_boolean
_bfd_link_hash_table_init(struct bfd_link_hash_table * table,bfd * abfd,struct bfd_hash_entry * (* newfunc)(struct bfd_hash_entry *,struct bfd_hash_table *,const char *),unsigned int entsize)471 _bfd_link_hash_table_init
472   (struct bfd_link_hash_table *table,
473    bfd *abfd,
474    struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
475 				      struct bfd_hash_table *,
476 				      const char *),
477    unsigned int entsize)
478 {
479   table->creator = abfd->xvec;
480   table->undefs = NULL;
481   table->undefs_tail = NULL;
482   table->type = bfd_link_generic_hash_table;
483 
484   return bfd_hash_table_init (&table->table, newfunc, entsize);
485 }
486 
487 /* Look up a symbol in a link hash table.  If follow is TRUE, we
488    follow bfd_link_hash_indirect and bfd_link_hash_warning links to
489    the real symbol.  */
490 
491 struct bfd_link_hash_entry *
bfd_link_hash_lookup(struct bfd_link_hash_table * table,const char * string,bfd_boolean create,bfd_boolean copy,bfd_boolean follow)492 bfd_link_hash_lookup (struct bfd_link_hash_table *table,
493 		      const char *string,
494 		      bfd_boolean create,
495 		      bfd_boolean copy,
496 		      bfd_boolean follow)
497 {
498   struct bfd_link_hash_entry *ret;
499 
500   ret = ((struct bfd_link_hash_entry *)
501 	 bfd_hash_lookup (&table->table, string, create, copy));
502 
503   if (follow && ret != NULL)
504     {
505       while (ret->type == bfd_link_hash_indirect
506 	     || ret->type == bfd_link_hash_warning)
507 	ret = ret->u.i.link;
508     }
509 
510   return ret;
511 }
512 
513 /* Look up a symbol in the main linker hash table if the symbol might
514    be wrapped.  This should only be used for references to an
515    undefined symbol, not for definitions of a symbol.  */
516 
517 struct bfd_link_hash_entry *
bfd_wrapped_link_hash_lookup(bfd * abfd,struct bfd_link_info * info,const char * string,bfd_boolean create,bfd_boolean copy,bfd_boolean follow)518 bfd_wrapped_link_hash_lookup (bfd *abfd,
519 			      struct bfd_link_info *info,
520 			      const char *string,
521 			      bfd_boolean create,
522 			      bfd_boolean copy,
523 			      bfd_boolean follow)
524 {
525   bfd_size_type amt;
526 
527   if (info->wrap_hash != NULL)
528     {
529       const char *l;
530       char prefix = '\0';
531 
532       l = string;
533       if (*l == bfd_get_symbol_leading_char (abfd) || *l == info->wrap_char)
534 	{
535 	  prefix = *l;
536 	  ++l;
537 	}
538 
539 #undef WRAP
540 #define WRAP "__wrap_"
541 
542       if (bfd_hash_lookup (info->wrap_hash, l, FALSE, FALSE) != NULL)
543 	{
544 	  char *n;
545 	  struct bfd_link_hash_entry *h;
546 
547 	  /* This symbol is being wrapped.  We want to replace all
548              references to SYM with references to __wrap_SYM.  */
549 
550 	  amt = strlen (l) + sizeof WRAP + 1;
551 	  n = bfd_malloc (amt);
552 	  if (n == NULL)
553 	    return NULL;
554 
555 	  n[0] = prefix;
556 	  n[1] = '\0';
557 	  strcat (n, WRAP);
558 	  strcat (n, l);
559 	  h = bfd_link_hash_lookup (info->hash, n, create, TRUE, follow);
560 	  free (n);
561 	  return h;
562 	}
563 
564 #undef WRAP
565 
566 #undef  REAL
567 #define REAL "__real_"
568 
569       if (*l == '_'
570 	  && CONST_STRNEQ (l, REAL)
571 	  && bfd_hash_lookup (info->wrap_hash, l + sizeof REAL - 1,
572 			      FALSE, FALSE) != NULL)
573 	{
574 	  char *n;
575 	  struct bfd_link_hash_entry *h;
576 
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.  */
580 
581 	  amt = strlen (l + sizeof REAL - 1) + 2;
582 	  n = bfd_malloc (amt);
583 	  if (n == NULL)
584 	    return NULL;
585 
586 	  n[0] = prefix;
587 	  n[1] = '\0';
588 	  strcat (n, l + sizeof REAL - 1);
589 	  h = bfd_link_hash_lookup (info->hash, n, create, TRUE, follow);
590 	  free (n);
591 	  return h;
592 	}
593 
594 #undef REAL
595     }
596 
597   return bfd_link_hash_lookup (info->hash, string, create, copy, follow);
598 }
599 
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
604    call.  */
605 
606 void
bfd_link_hash_traverse(struct bfd_link_hash_table * table,bfd_boolean (* func)(struct bfd_link_hash_entry *,void *),void * info)607 bfd_link_hash_traverse
608   (struct bfd_link_hash_table *table,
609    bfd_boolean (*func) (struct bfd_link_hash_entry *, void *),
610    void *info)
611 {
612   bfd_hash_traverse (&table->table,
613 		     (bfd_boolean (*) (struct bfd_hash_entry *, void *)) func,
614 		     info);
615 }
616 
617 /* Add a symbol to the linker hash table undefs list.  */
618 
619 void
bfd_link_add_undef(struct bfd_link_hash_table * table,struct bfd_link_hash_entry * h)620 bfd_link_add_undef (struct bfd_link_hash_table *table,
621 		    struct bfd_link_hash_entry *h)
622 {
623   BFD_ASSERT (h->u.undef.next == NULL);
624   if (table->undefs_tail != NULL)
625     table->undefs_tail->u.undef.next = h;
626   if (table->undefs == NULL)
627     table->undefs = h;
628   table->undefs_tail = h;
629 }
630 
631 /* The undefs list was designed so that in normal use we don't need to
632    remove entries.  However, if symbols on the list are changed from
633    bfd_link_hash_undefined to either bfd_link_hash_undefweak or
634    bfd_link_hash_new for some reason, then they must be removed from the
635    list.  Failure to do so might result in the linker attempting to add
636    the symbol to the list again at a later stage.  */
637 
638 void
bfd_link_repair_undef_list(struct bfd_link_hash_table * table)639 bfd_link_repair_undef_list (struct bfd_link_hash_table *table)
640 {
641   struct bfd_link_hash_entry **pun;
642 
643   pun = &table->undefs;
644   while (*pun != NULL)
645     {
646       struct bfd_link_hash_entry *h = *pun;
647 
648       if (h->type == bfd_link_hash_new
649 	  || h->type == bfd_link_hash_undefweak)
650 	{
651 	  *pun = h->u.undef.next;
652 	  h->u.undef.next = NULL;
653 	  if (h == table->undefs_tail)
654 	    {
655 	      if (pun == &table->undefs)
656 		table->undefs_tail = NULL;
657 	      else
658 		/* pun points at an u.undef.next field.  Go back to
659 		   the start of the link_hash_entry.  */
660 		table->undefs_tail = (struct bfd_link_hash_entry *)
661 		  ((char *) pun - ((char *) &h->u.undef.next - (char *) h));
662 	      break;
663 	    }
664 	}
665       else
666 	pun = &h->u.undef.next;
667     }
668 }
669 
670 /* Routine to create an entry in a generic link hash table.  */
671 
672 struct bfd_hash_entry *
_bfd_generic_link_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)673 _bfd_generic_link_hash_newfunc (struct bfd_hash_entry *entry,
674 				struct bfd_hash_table *table,
675 				const char *string)
676 {
677   /* Allocate the structure if it has not already been allocated by a
678      subclass.  */
679   if (entry == NULL)
680     {
681       entry =
682 	bfd_hash_allocate (table, sizeof (struct generic_link_hash_entry));
683       if (entry == NULL)
684 	return entry;
685     }
686 
687   /* Call the allocation method of the superclass.  */
688   entry = _bfd_link_hash_newfunc (entry, table, string);
689   if (entry)
690     {
691       struct generic_link_hash_entry *ret;
692 
693       /* Set local fields.  */
694       ret = (struct generic_link_hash_entry *) entry;
695       ret->written = FALSE;
696       ret->sym = NULL;
697     }
698 
699   return entry;
700 }
701 
702 /* Create a generic link hash table.  */
703 
704 struct bfd_link_hash_table *
_bfd_generic_link_hash_table_create(bfd * abfd)705 _bfd_generic_link_hash_table_create (bfd *abfd)
706 {
707   struct generic_link_hash_table *ret;
708   bfd_size_type amt = sizeof (struct generic_link_hash_table);
709 
710   ret = bfd_malloc (amt);
711   if (ret == NULL)
712     return NULL;
713   if (! _bfd_link_hash_table_init (&ret->root, abfd,
714 				   _bfd_generic_link_hash_newfunc,
715 				   sizeof (struct generic_link_hash_entry)))
716     {
717       free (ret);
718       return NULL;
719     }
720   return &ret->root;
721 }
722 
723 void
_bfd_generic_link_hash_table_free(struct bfd_link_hash_table * hash)724 _bfd_generic_link_hash_table_free (struct bfd_link_hash_table *hash)
725 {
726   struct generic_link_hash_table *ret
727     = (struct generic_link_hash_table *) hash;
728 
729   bfd_hash_table_free (&ret->root.table);
730   free (ret);
731 }
732 
733 /* Grab the symbols for an object file when doing a generic link.  We
734    store the symbols in the outsymbols field.  We need to keep them
735    around for the entire link to ensure that we only read them once.
736    If we read them multiple times, we might wind up with relocs and
737    the hash table pointing to different instances of the symbol
738    structure.  */
739 
740 static bfd_boolean
generic_link_read_symbols(bfd * abfd)741 generic_link_read_symbols (bfd *abfd)
742 {
743   if (bfd_get_outsymbols (abfd) == NULL)
744     {
745       long symsize;
746       long symcount;
747 
748       symsize = bfd_get_symtab_upper_bound (abfd);
749       if (symsize < 0)
750 	return FALSE;
751       bfd_get_outsymbols (abfd) = bfd_alloc (abfd, symsize);
752       if (bfd_get_outsymbols (abfd) == NULL && symsize != 0)
753 	return FALSE;
754       symcount = bfd_canonicalize_symtab (abfd, bfd_get_outsymbols (abfd));
755       if (symcount < 0)
756 	return FALSE;
757       bfd_get_symcount (abfd) = symcount;
758     }
759 
760   return TRUE;
761 }
762 
763 /* Generic function to add symbols to from an object file to the
764    global hash table.  This version does not automatically collect
765    constructors by name.  */
766 
767 bfd_boolean
_bfd_generic_link_add_symbols(bfd * abfd,struct bfd_link_info * info)768 _bfd_generic_link_add_symbols (bfd *abfd, struct bfd_link_info *info)
769 {
770   return generic_link_add_symbols (abfd, info, FALSE);
771 }
772 
773 /* Generic function to add symbols from an object file to the global
774    hash table.  This version automatically collects constructors by
775    name, as the collect2 program does.  It should be used for any
776    target which does not provide some other mechanism for setting up
777    constructors and destructors; these are approximately those targets
778    for which gcc uses collect2 and do not support stabs.  */
779 
780 bfd_boolean
_bfd_generic_link_add_symbols_collect(bfd * abfd,struct bfd_link_info * info)781 _bfd_generic_link_add_symbols_collect (bfd *abfd, struct bfd_link_info *info)
782 {
783   return generic_link_add_symbols (abfd, info, TRUE);
784 }
785 
786 /* Indicate that we are only retrieving symbol values from this
787    section.  We want the symbols to act as though the values in the
788    file are absolute.  */
789 
790 void
_bfd_generic_link_just_syms(asection * sec,struct bfd_link_info * info ATTRIBUTE_UNUSED)791 _bfd_generic_link_just_syms (asection *sec,
792 			     struct bfd_link_info *info ATTRIBUTE_UNUSED)
793 {
794   sec->output_section = bfd_abs_section_ptr;
795   sec->output_offset = sec->vma;
796 }
797 
798 /* Add symbols from an object file to the global hash table.  */
799 
800 static bfd_boolean
generic_link_add_symbols(bfd * abfd,struct bfd_link_info * info,bfd_boolean collect)801 generic_link_add_symbols (bfd *abfd,
802 			  struct bfd_link_info *info,
803 			  bfd_boolean collect)
804 {
805   bfd_boolean ret;
806 
807   switch (bfd_get_format (abfd))
808     {
809     case bfd_object:
810       ret = generic_link_add_object_symbols (abfd, info, collect);
811       break;
812     case bfd_archive:
813       ret = (_bfd_generic_link_add_archive_symbols
814 	     (abfd, info,
815 	      (collect
816 	       ? generic_link_check_archive_element_collect
817 	       : generic_link_check_archive_element_no_collect)));
818       break;
819     default:
820       bfd_set_error (bfd_error_wrong_format);
821       ret = FALSE;
822     }
823 
824   return ret;
825 }
826 
827 /* Add symbols from an object file to the global hash table.  */
828 
829 static bfd_boolean
generic_link_add_object_symbols(bfd * abfd,struct bfd_link_info * info,bfd_boolean collect)830 generic_link_add_object_symbols (bfd *abfd,
831 				 struct bfd_link_info *info,
832 				 bfd_boolean collect)
833 {
834   bfd_size_type symcount;
835   struct bfd_symbol **outsyms;
836 
837   if (! generic_link_read_symbols (abfd))
838     return FALSE;
839   symcount = _bfd_generic_link_get_symcount (abfd);
840   outsyms = _bfd_generic_link_get_symbols (abfd);
841   return generic_link_add_symbol_list (abfd, info, symcount, outsyms, collect);
842 }
843 
844 /* We build a hash table of all symbols defined in an archive.  */
845 
846 /* An archive symbol may be defined by multiple archive elements.
847    This linked list is used to hold the elements.  */
848 
849 struct archive_list
850 {
851   struct archive_list *next;
852   unsigned int indx;
853 };
854 
855 /* An entry in an archive hash table.  */
856 
857 struct archive_hash_entry
858 {
859   struct bfd_hash_entry root;
860   /* Where the symbol is defined.  */
861   struct archive_list *defs;
862 };
863 
864 /* An archive hash table itself.  */
865 
866 struct archive_hash_table
867 {
868   struct bfd_hash_table table;
869 };
870 
871 /* Create a new entry for an archive hash table.  */
872 
873 static struct bfd_hash_entry *
archive_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)874 archive_hash_newfunc (struct bfd_hash_entry *entry,
875 		      struct bfd_hash_table *table,
876 		      const char *string)
877 {
878   struct archive_hash_entry *ret = (struct archive_hash_entry *) entry;
879 
880   /* Allocate the structure if it has not already been allocated by a
881      subclass.  */
882   if (ret == NULL)
883     ret = bfd_hash_allocate (table, sizeof (struct archive_hash_entry));
884   if (ret == NULL)
885     return NULL;
886 
887   /* Call the allocation method of the superclass.  */
888   ret = ((struct archive_hash_entry *)
889 	 bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string));
890 
891   if (ret)
892     {
893       /* Initialize the local fields.  */
894       ret->defs = NULL;
895     }
896 
897   return &ret->root;
898 }
899 
900 /* Initialize an archive hash table.  */
901 
902 static bfd_boolean
archive_hash_table_init(struct archive_hash_table * table,struct bfd_hash_entry * (* newfunc)(struct bfd_hash_entry *,struct bfd_hash_table *,const char *),unsigned int entsize)903 archive_hash_table_init
904   (struct archive_hash_table *table,
905    struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
906 				      struct bfd_hash_table *,
907 				      const char *),
908    unsigned int entsize)
909 {
910   return bfd_hash_table_init (&table->table, newfunc, entsize);
911 }
912 
913 /* Look up an entry in an archive hash table.  */
914 
915 #define archive_hash_lookup(t, string, create, copy) \
916   ((struct archive_hash_entry *) \
917    bfd_hash_lookup (&(t)->table, (string), (create), (copy)))
918 
919 /* Allocate space in an archive hash table.  */
920 
921 #define archive_hash_allocate(t, size) bfd_hash_allocate (&(t)->table, (size))
922 
923 /* Free an archive hash table.  */
924 
925 #define archive_hash_table_free(t) bfd_hash_table_free (&(t)->table)
926 
927 /* Generic function to add symbols from an archive file to the global
928    hash file.  This function presumes that the archive symbol table
929    has already been read in (this is normally done by the
930    bfd_check_format entry point).  It looks through the undefined and
931    common symbols and searches the archive symbol table for them.  If
932    it finds an entry, it includes the associated object file in the
933    link.
934 
935    The old linker looked through the archive symbol table for
936    undefined symbols.  We do it the other way around, looking through
937    undefined symbols for symbols defined in the archive.  The
938    advantage of the newer scheme is that we only have to look through
939    the list of undefined symbols once, whereas the old method had to
940    re-search the symbol table each time a new object file was added.
941 
942    The CHECKFN argument is used to see if an object file should be
943    included.  CHECKFN should set *PNEEDED to TRUE if the object file
944    should be included, and must also call the bfd_link_info
945    add_archive_element callback function and handle adding the symbols
946    to the global hash table.  CHECKFN should only return FALSE if some
947    sort of error occurs.
948 
949    For some formats, such as a.out, it is possible to look through an
950    object file but not actually include it in the link.  The
951    archive_pass field in a BFD is used to avoid checking the symbols
952    of an object files too many times.  When an object is included in
953    the link, archive_pass is set to -1.  If an object is scanned but
954    not included, archive_pass is set to the pass number.  The pass
955    number is incremented each time a new object file is included.  The
956    pass number is used because when a new object file is included it
957    may create new undefined symbols which cause a previously examined
958    object file to be included.  */
959 
960 bfd_boolean
_bfd_generic_link_add_archive_symbols(bfd * abfd,struct bfd_link_info * info,bfd_boolean (* checkfn)(bfd *,struct bfd_link_info *,bfd_boolean *))961 _bfd_generic_link_add_archive_symbols
962   (bfd *abfd,
963    struct bfd_link_info *info,
964    bfd_boolean (*checkfn) (bfd *, struct bfd_link_info *, bfd_boolean *))
965 {
966   carsym *arsyms;
967   carsym *arsym_end;
968   register carsym *arsym;
969   int pass;
970   struct archive_hash_table arsym_hash;
971   unsigned int indx;
972   struct bfd_link_hash_entry **pundef;
973 
974   if (! bfd_has_map (abfd))
975     {
976       /* An empty archive is a special case.  */
977       if (bfd_openr_next_archived_file (abfd, NULL) == NULL)
978 	return TRUE;
979       bfd_set_error (bfd_error_no_armap);
980       return FALSE;
981     }
982 
983   arsyms = bfd_ardata (abfd)->symdefs;
984   arsym_end = arsyms + bfd_ardata (abfd)->symdef_count;
985 
986   /* In order to quickly determine whether an symbol is defined in
987      this archive, we build a hash table of the symbols.  */
988   if (! archive_hash_table_init (&arsym_hash, archive_hash_newfunc,
989 				 sizeof (struct archive_hash_entry)))
990     return FALSE;
991   for (arsym = arsyms, indx = 0; arsym < arsym_end; arsym++, indx++)
992     {
993       struct archive_hash_entry *arh;
994       struct archive_list *l, **pp;
995 
996       arh = archive_hash_lookup (&arsym_hash, arsym->name, TRUE, FALSE);
997       if (arh == NULL)
998 	goto error_return;
999       l = ((struct archive_list *)
1000 	   archive_hash_allocate (&arsym_hash, sizeof (struct archive_list)));
1001       if (l == NULL)
1002 	goto error_return;
1003       l->indx = indx;
1004       for (pp = &arh->defs; *pp != NULL; pp = &(*pp)->next)
1005 	;
1006       *pp = l;
1007       l->next = NULL;
1008     }
1009 
1010   /* The archive_pass field in the archive itself is used to
1011      initialize PASS, sine we may search the same archive multiple
1012      times.  */
1013   pass = abfd->archive_pass + 1;
1014 
1015   /* New undefined symbols are added to the end of the list, so we
1016      only need to look through it once.  */
1017   pundef = &info->hash->undefs;
1018   while (*pundef != NULL)
1019     {
1020       struct bfd_link_hash_entry *h;
1021       struct archive_hash_entry *arh;
1022       struct archive_list *l;
1023 
1024       h = *pundef;
1025 
1026       /* When a symbol is defined, it is not necessarily removed from
1027 	 the list.  */
1028       if (h->type != bfd_link_hash_undefined
1029 	  && h->type != bfd_link_hash_common)
1030 	{
1031 	  /* Remove this entry from the list, for general cleanliness
1032 	     and because we are going to look through the list again
1033 	     if we search any more libraries.  We can't remove the
1034 	     entry if it is the tail, because that would lose any
1035 	     entries we add to the list later on (it would also cause
1036 	     us to lose track of whether the symbol has been
1037 	     referenced).  */
1038 	  if (*pundef != info->hash->undefs_tail)
1039 	    *pundef = (*pundef)->u.undef.next;
1040 	  else
1041 	    pundef = &(*pundef)->u.undef.next;
1042 	  continue;
1043 	}
1044 
1045       /* Look for this symbol in the archive symbol map.  */
1046       arh = archive_hash_lookup (&arsym_hash, h->root.string, FALSE, FALSE);
1047       if (arh == NULL)
1048 	{
1049 	  /* If we haven't found the exact symbol we're looking for,
1050 	     let's look for its import thunk */
1051 	  if (info->pei386_auto_import)
1052 	    {
1053 	      bfd_size_type amt = strlen (h->root.string) + 10;
1054 	      char *buf = bfd_malloc (amt);
1055 	      if (buf == NULL)
1056 		return FALSE;
1057 
1058 	      sprintf (buf, "__imp_%s", h->root.string);
1059 	      arh = archive_hash_lookup (&arsym_hash, buf, FALSE, FALSE);
1060 	      free(buf);
1061 	    }
1062 	  if (arh == NULL)
1063 	    {
1064 	      pundef = &(*pundef)->u.undef.next;
1065 	      continue;
1066 	    }
1067 	}
1068       /* Look at all the objects which define this symbol.  */
1069       for (l = arh->defs; l != NULL; l = l->next)
1070 	{
1071 	  bfd *element;
1072 	  bfd_boolean needed;
1073 
1074 	  /* If the symbol has gotten defined along the way, quit.  */
1075 	  if (h->type != bfd_link_hash_undefined
1076 	      && h->type != bfd_link_hash_common)
1077 	    break;
1078 
1079 	  element = bfd_get_elt_at_index (abfd, l->indx);
1080 	  if (element == NULL)
1081 	    goto error_return;
1082 
1083 	  /* If we've already included this element, or if we've
1084 	     already checked it on this pass, continue.  */
1085 	  if (element->archive_pass == -1
1086 	      || element->archive_pass == pass)
1087 	    continue;
1088 
1089 	  /* If we can't figure this element out, just ignore it.  */
1090 	  if (! bfd_check_format (element, bfd_object))
1091 	    {
1092 	      element->archive_pass = -1;
1093 	      continue;
1094 	    }
1095 
1096 	  /* CHECKFN will see if this element should be included, and
1097 	     go ahead and include it if appropriate.  */
1098 	  if (! (*checkfn) (element, info, &needed))
1099 	    goto error_return;
1100 
1101 	  if (! needed)
1102 	    element->archive_pass = pass;
1103 	  else
1104 	    {
1105 	      element->archive_pass = -1;
1106 
1107 	      /* Increment the pass count to show that we may need to
1108 		 recheck object files which were already checked.  */
1109 	      ++pass;
1110 	    }
1111 	}
1112 
1113       pundef = &(*pundef)->u.undef.next;
1114     }
1115 
1116   archive_hash_table_free (&arsym_hash);
1117 
1118   /* Save PASS in case we are called again.  */
1119   abfd->archive_pass = pass;
1120 
1121   return TRUE;
1122 
1123  error_return:
1124   archive_hash_table_free (&arsym_hash);
1125   return FALSE;
1126 }
1127 
1128 /* See if we should include an archive element.  This version is used
1129    when we do not want to automatically collect constructors based on
1130    the symbol name, presumably because we have some other mechanism
1131    for finding them.  */
1132 
1133 static bfd_boolean
generic_link_check_archive_element_no_collect(bfd * abfd,struct bfd_link_info * info,bfd_boolean * pneeded)1134 generic_link_check_archive_element_no_collect (
1135 					       bfd *abfd,
1136 					       struct bfd_link_info *info,
1137 					       bfd_boolean *pneeded)
1138 {
1139   return generic_link_check_archive_element (abfd, info, pneeded, FALSE);
1140 }
1141 
1142 /* See if we should include an archive element.  This version is used
1143    when we want to automatically collect constructors based on the
1144    symbol name, as collect2 does.  */
1145 
1146 static bfd_boolean
generic_link_check_archive_element_collect(bfd * abfd,struct bfd_link_info * info,bfd_boolean * pneeded)1147 generic_link_check_archive_element_collect (bfd *abfd,
1148 					    struct bfd_link_info *info,
1149 					    bfd_boolean *pneeded)
1150 {
1151   return generic_link_check_archive_element (abfd, info, pneeded, TRUE);
1152 }
1153 
1154 /* See if we should include an archive element.  Optionally collect
1155    constructors.  */
1156 
1157 static bfd_boolean
generic_link_check_archive_element(bfd * abfd,struct bfd_link_info * info,bfd_boolean * pneeded,bfd_boolean collect)1158 generic_link_check_archive_element (bfd *abfd,
1159 				    struct bfd_link_info *info,
1160 				    bfd_boolean *pneeded,
1161 				    bfd_boolean collect)
1162 {
1163   asymbol **pp, **ppend;
1164 
1165   *pneeded = FALSE;
1166 
1167   if (! generic_link_read_symbols (abfd))
1168     return FALSE;
1169 
1170   pp = _bfd_generic_link_get_symbols (abfd);
1171   ppend = pp + _bfd_generic_link_get_symcount (abfd);
1172   for (; pp < ppend; pp++)
1173     {
1174       asymbol *p;
1175       struct bfd_link_hash_entry *h;
1176 
1177       p = *pp;
1178 
1179       /* We are only interested in globally visible symbols.  */
1180       if (! bfd_is_com_section (p->section)
1181 	  && (p->flags & (BSF_GLOBAL | BSF_INDIRECT | BSF_WEAK)) == 0)
1182 	continue;
1183 
1184       /* We are only interested if we know something about this
1185 	 symbol, and it is undefined or common.  An undefined weak
1186 	 symbol (type bfd_link_hash_undefweak) is not considered to be
1187 	 a reference when pulling files out of an archive.  See the
1188 	 SVR4 ABI, p. 4-27.  */
1189       h = bfd_link_hash_lookup (info->hash, bfd_asymbol_name (p), FALSE,
1190 				FALSE, TRUE);
1191       if (h == NULL
1192 	  || (h->type != bfd_link_hash_undefined
1193 	      && h->type != bfd_link_hash_common))
1194 	continue;
1195 
1196       /* P is a symbol we are looking for.  */
1197 
1198       if (! bfd_is_com_section (p->section))
1199 	{
1200 	  bfd_size_type symcount;
1201 	  asymbol **symbols;
1202 
1203 	  /* This object file defines this symbol, so pull it in.  */
1204 	  if (! (*info->callbacks->add_archive_element) (info, abfd,
1205 							 bfd_asymbol_name (p)))
1206 	    return FALSE;
1207 	  symcount = _bfd_generic_link_get_symcount (abfd);
1208 	  symbols = _bfd_generic_link_get_symbols (abfd);
1209 	  if (! generic_link_add_symbol_list (abfd, info, symcount,
1210 					      symbols, collect))
1211 	    return FALSE;
1212 	  *pneeded = TRUE;
1213 	  return TRUE;
1214 	}
1215 
1216       /* P is a common symbol.  */
1217 
1218       if (h->type == bfd_link_hash_undefined)
1219 	{
1220 	  bfd *symbfd;
1221 	  bfd_vma size;
1222 	  unsigned int power;
1223 
1224 	  symbfd = h->u.undef.abfd;
1225 	  if (symbfd == NULL)
1226 	    {
1227 	      /* This symbol was created as undefined from outside
1228 		 BFD.  We assume that we should link in the object
1229 		 file.  This is for the -u option in the linker.  */
1230 	      if (! (*info->callbacks->add_archive_element)
1231 		  (info, abfd, bfd_asymbol_name (p)))
1232 		return FALSE;
1233 	      *pneeded = TRUE;
1234 	      return TRUE;
1235 	    }
1236 
1237 	  /* Turn the symbol into a common symbol but do not link in
1238 	     the object file.  This is how a.out works.  Object
1239 	     formats that require different semantics must implement
1240 	     this function differently.  This symbol is already on the
1241 	     undefs list.  We add the section to a common section
1242 	     attached to symbfd to ensure that it is in a BFD which
1243 	     will be linked in.  */
1244 	  h->type = bfd_link_hash_common;
1245 	  h->u.c.p =
1246 	    bfd_hash_allocate (&info->hash->table,
1247 			       sizeof (struct bfd_link_hash_common_entry));
1248 	  if (h->u.c.p == NULL)
1249 	    return FALSE;
1250 
1251 	  size = bfd_asymbol_value (p);
1252 	  h->u.c.size = size;
1253 
1254 	  power = bfd_log2 (size);
1255 	  if (power > 4)
1256 	    power = 4;
1257 	  h->u.c.p->alignment_power = power;
1258 
1259 	  if (p->section == bfd_com_section_ptr)
1260 	    h->u.c.p->section = bfd_make_section_old_way (symbfd, "COMMON");
1261 	  else
1262 	    h->u.c.p->section = bfd_make_section_old_way (symbfd,
1263 							  p->section->name);
1264 	  h->u.c.p->section->flags = SEC_ALLOC;
1265 	}
1266       else
1267 	{
1268 	  /* Adjust the size of the common symbol if necessary.  This
1269 	     is how a.out works.  Object formats that require
1270 	     different semantics must implement this function
1271 	     differently.  */
1272 	  if (bfd_asymbol_value (p) > h->u.c.size)
1273 	    h->u.c.size = bfd_asymbol_value (p);
1274 	}
1275     }
1276 
1277   /* This archive element is not needed.  */
1278   return TRUE;
1279 }
1280 
1281 /* Add the symbols from an object file to the global hash table.  ABFD
1282    is the object file.  INFO is the linker information.  SYMBOL_COUNT
1283    is the number of symbols.  SYMBOLS is the list of symbols.  COLLECT
1284    is TRUE if constructors should be automatically collected by name
1285    as is done by collect2.  */
1286 
1287 static bfd_boolean
generic_link_add_symbol_list(bfd * abfd,struct bfd_link_info * info,bfd_size_type symbol_count,asymbol ** symbols,bfd_boolean collect)1288 generic_link_add_symbol_list (bfd *abfd,
1289 			      struct bfd_link_info *info,
1290 			      bfd_size_type symbol_count,
1291 			      asymbol **symbols,
1292 			      bfd_boolean collect)
1293 {
1294   asymbol **pp, **ppend;
1295 
1296   pp = symbols;
1297   ppend = symbols + symbol_count;
1298   for (; pp < ppend; pp++)
1299     {
1300       asymbol *p;
1301 
1302       p = *pp;
1303 
1304       if ((p->flags & (BSF_INDIRECT
1305 		       | BSF_WARNING
1306 		       | BSF_GLOBAL
1307 		       | BSF_CONSTRUCTOR
1308 		       | BSF_WEAK)) != 0
1309 	  || bfd_is_und_section (bfd_get_section (p))
1310 	  || bfd_is_com_section (bfd_get_section (p))
1311 	  || bfd_is_ind_section (bfd_get_section (p)))
1312 	{
1313 	  const char *name;
1314 	  const char *string;
1315 	  struct generic_link_hash_entry *h;
1316 	  struct bfd_link_hash_entry *bh;
1317 
1318 	  name = bfd_asymbol_name (p);
1319 	  if (((p->flags & BSF_INDIRECT) != 0
1320 	       || bfd_is_ind_section (p->section))
1321 	      && pp + 1 < ppend)
1322 	    {
1323 	      pp++;
1324 	      string = bfd_asymbol_name (*pp);
1325 	    }
1326 	  else if ((p->flags & BSF_WARNING) != 0
1327 		   && pp + 1 < ppend)
1328 	    {
1329 	      /* The name of P is actually the warning string, and the
1330 		 next symbol is the one to warn about.  */
1331 	      string = name;
1332 	      pp++;
1333 	      name = bfd_asymbol_name (*pp);
1334 	    }
1335 	  else
1336 	    string = NULL;
1337 
1338 	  bh = NULL;
1339 	  if (! (_bfd_generic_link_add_one_symbol
1340 		 (info, abfd, name, p->flags, bfd_get_section (p),
1341 		  p->value, string, FALSE, collect, &bh)))
1342 	    return FALSE;
1343 	  h = (struct generic_link_hash_entry *) bh;
1344 
1345 	  /* If this is a constructor symbol, and the linker didn't do
1346              anything with it, then we want to just pass the symbol
1347              through to the output file.  This will happen when
1348              linking with -r.  */
1349 	  if ((p->flags & BSF_CONSTRUCTOR) != 0
1350 	      && (h == NULL || h->root.type == bfd_link_hash_new))
1351 	    {
1352 	      p->udata.p = NULL;
1353 	      continue;
1354 	    }
1355 
1356 	  /* Save the BFD symbol so that we don't lose any backend
1357 	     specific information that may be attached to it.  We only
1358 	     want this one if it gives more information than the
1359 	     existing one; we don't want to replace a defined symbol
1360 	     with an undefined one.  This routine may be called with a
1361 	     hash table other than the generic hash table, so we only
1362 	     do this if we are certain that the hash table is a
1363 	     generic one.  */
1364 	  if (info->hash->creator == abfd->xvec)
1365 	    {
1366 	      if (h->sym == NULL
1367 		  || (! bfd_is_und_section (bfd_get_section (p))
1368 		      && (! bfd_is_com_section (bfd_get_section (p))
1369 			  || bfd_is_und_section (bfd_get_section (h->sym)))))
1370 		{
1371 		  h->sym = p;
1372 		  /* BSF_OLD_COMMON is a hack to support COFF reloc
1373 		     reading, and it should go away when the COFF
1374 		     linker is switched to the new version.  */
1375 		  if (bfd_is_com_section (bfd_get_section (p)))
1376 		    p->flags |= BSF_OLD_COMMON;
1377 		}
1378 	    }
1379 
1380 	  /* Store a back pointer from the symbol to the hash
1381 	     table entry for the benefit of relaxation code until
1382 	     it gets rewritten to not use asymbol structures.
1383 	     Setting this is also used to check whether these
1384 	     symbols were set up by the generic linker.  */
1385 	  p->udata.p = h;
1386 	}
1387     }
1388 
1389   return TRUE;
1390 }
1391 
1392 /* We use a state table to deal with adding symbols from an object
1393    file.  The first index into the state table describes the symbol
1394    from the object file.  The second index into the state table is the
1395    type of the symbol in the hash table.  */
1396 
1397 /* The symbol from the object file is turned into one of these row
1398    values.  */
1399 
1400 enum link_row
1401 {
1402   UNDEF_ROW,		/* Undefined.  */
1403   UNDEFW_ROW,		/* Weak undefined.  */
1404   DEF_ROW,		/* Defined.  */
1405   DEFW_ROW,		/* Weak defined.  */
1406   COMMON_ROW,		/* Common.  */
1407   INDR_ROW,		/* Indirect.  */
1408   WARN_ROW,		/* Warning.  */
1409   SET_ROW		/* Member of set.  */
1410 };
1411 
1412 /* apparently needed for Hitachi 3050R(HI-UX/WE2)? */
1413 #undef FAIL
1414 
1415 /* The actions to take in the state table.  */
1416 
1417 enum link_action
1418 {
1419   FAIL,		/* Abort.  */
1420   UND,		/* Mark symbol undefined.  */
1421   WEAK,		/* Mark symbol weak undefined.  */
1422   DEF,		/* Mark symbol defined.  */
1423   DEFW,		/* Mark symbol weak defined.  */
1424   COM,		/* Mark symbol common.  */
1425   REF,		/* Mark defined symbol referenced.  */
1426   CREF,		/* Possibly warn about common reference to defined symbol.  */
1427   CDEF,		/* Define existing common symbol.  */
1428   NOACT,	/* No action.  */
1429   BIG,		/* Mark symbol common using largest size.  */
1430   MDEF,		/* Multiple definition error.  */
1431   MIND,		/* Multiple indirect symbols.  */
1432   IND,		/* Make indirect symbol.  */
1433   CIND,		/* Make indirect symbol from existing common symbol.  */
1434   SET,		/* Add value to set.  */
1435   MWARN,	/* Make warning symbol.  */
1436   WARN,		/* Issue warning.  */
1437   CWARN,	/* Warn if referenced, else MWARN.  */
1438   CYCLE,	/* Repeat with symbol pointed to.  */
1439   REFC,		/* Mark indirect symbol referenced and then CYCLE.  */
1440   WARNC		/* Issue warning and then CYCLE.  */
1441 };
1442 
1443 /* The state table itself.  The first index is a link_row and the
1444    second index is a bfd_link_hash_type.  */
1445 
1446 static const enum link_action link_action[8][8] =
1447 {
1448   /* current\prev    new    undef  undefw def    defw   com    indr   warn  */
1449   /* UNDEF_ROW 	*/  {UND,   NOACT, UND,   REF,   REF,   NOACT, REFC,  WARNC },
1450   /* UNDEFW_ROW	*/  {WEAK,  NOACT, NOACT, REF,   REF,   NOACT, REFC,  WARNC },
1451   /* DEF_ROW 	*/  {DEF,   DEF,   DEF,   MDEF,  DEF,   CDEF,  MDEF,  CYCLE },
1452   /* DEFW_ROW 	*/  {DEFW,  DEFW,  DEFW,  NOACT, NOACT, NOACT, NOACT, CYCLE },
1453   /* COMMON_ROW	*/  {COM,   COM,   COM,   CREF,  COM,   BIG,   REFC,  WARNC },
1454   /* INDR_ROW	*/  {IND,   IND,   IND,   MDEF,  IND,   CIND,  MIND,  CYCLE },
1455   /* WARN_ROW   */  {MWARN, WARN,  WARN,  CWARN, CWARN, WARN,  CWARN, NOACT },
1456   /* SET_ROW	*/  {SET,   SET,   SET,   SET,   SET,   SET,   CYCLE, CYCLE }
1457 };
1458 
1459 /* Most of the entries in the LINK_ACTION table are straightforward,
1460    but a few are somewhat subtle.
1461 
1462    A reference to an indirect symbol (UNDEF_ROW/indr or
1463    UNDEFW_ROW/indr) is counted as a reference both to the indirect
1464    symbol and to the symbol the indirect symbol points to.
1465 
1466    A reference to a warning symbol (UNDEF_ROW/warn or UNDEFW_ROW/warn)
1467    causes the warning to be issued.
1468 
1469    A common definition of an indirect symbol (COMMON_ROW/indr) is
1470    treated as a multiple definition error.  Likewise for an indirect
1471    definition of a common symbol (INDR_ROW/com).
1472 
1473    An indirect definition of a warning (INDR_ROW/warn) does not cause
1474    the warning to be issued.
1475 
1476    If a warning is created for an indirect symbol (WARN_ROW/indr) no
1477    warning is created for the symbol the indirect symbol points to.
1478 
1479    Adding an entry to a set does not count as a reference to a set,
1480    and no warning is issued (SET_ROW/warn).  */
1481 
1482 /* Return the BFD in which a hash entry has been defined, if known.  */
1483 
1484 static bfd *
hash_entry_bfd(struct bfd_link_hash_entry * h)1485 hash_entry_bfd (struct bfd_link_hash_entry *h)
1486 {
1487   while (h->type == bfd_link_hash_warning)
1488     h = h->u.i.link;
1489   switch (h->type)
1490     {
1491     default:
1492       return NULL;
1493     case bfd_link_hash_undefined:
1494     case bfd_link_hash_undefweak:
1495       return h->u.undef.abfd;
1496     case bfd_link_hash_defined:
1497     case bfd_link_hash_defweak:
1498       return h->u.def.section->owner;
1499     case bfd_link_hash_common:
1500       return h->u.c.p->section->owner;
1501     }
1502   /*NOTREACHED*/
1503 }
1504 
1505 /* Add a symbol to the global hash table.
1506    ABFD is the BFD the symbol comes from.
1507    NAME is the name of the symbol.
1508    FLAGS is the BSF_* bits associated with the symbol.
1509    SECTION is the section in which the symbol is defined; this may be
1510      bfd_und_section_ptr or bfd_com_section_ptr.
1511    VALUE is the value of the symbol, relative to the section.
1512    STRING is used for either an indirect symbol, in which case it is
1513      the name of the symbol to indirect to, or a warning symbol, in
1514      which case it is the warning string.
1515    COPY is TRUE if NAME or STRING must be copied into locally
1516      allocated memory if they need to be saved.
1517    COLLECT is TRUE if we should automatically collect gcc constructor
1518      or destructor names as collect2 does.
1519    HASHP, if not NULL, is a place to store the created hash table
1520      entry; if *HASHP is not NULL, the caller has already looked up
1521      the hash table entry, and stored it in *HASHP.  */
1522 
1523 bfd_boolean
_bfd_generic_link_add_one_symbol(struct bfd_link_info * info,bfd * abfd,const char * name,flagword flags,asection * section,bfd_vma value,const char * string,bfd_boolean copy,bfd_boolean collect,struct bfd_link_hash_entry ** hashp)1524 _bfd_generic_link_add_one_symbol (struct bfd_link_info *info,
1525 				  bfd *abfd,
1526 				  const char *name,
1527 				  flagword flags,
1528 				  asection *section,
1529 				  bfd_vma value,
1530 				  const char *string,
1531 				  bfd_boolean copy,
1532 				  bfd_boolean collect,
1533 				  struct bfd_link_hash_entry **hashp)
1534 {
1535   enum link_row row;
1536   struct bfd_link_hash_entry *h;
1537   bfd_boolean cycle;
1538 
1539   if (bfd_is_ind_section (section)
1540       || (flags & BSF_INDIRECT) != 0)
1541     row = INDR_ROW;
1542   else if ((flags & BSF_WARNING) != 0)
1543     row = WARN_ROW;
1544   else if ((flags & BSF_CONSTRUCTOR) != 0)
1545     row = SET_ROW;
1546   else if (bfd_is_und_section (section))
1547     {
1548       if ((flags & BSF_WEAK) != 0)
1549 	row = UNDEFW_ROW;
1550       else
1551 	row = UNDEF_ROW;
1552     }
1553   else if ((flags & BSF_WEAK) != 0)
1554     row = DEFW_ROW;
1555   else if (bfd_is_com_section (section))
1556     row = COMMON_ROW;
1557   else
1558     row = DEF_ROW;
1559 
1560   if (hashp != NULL && *hashp != NULL)
1561     h = *hashp;
1562   else
1563     {
1564       if (row == UNDEF_ROW || row == UNDEFW_ROW)
1565 	h = bfd_wrapped_link_hash_lookup (abfd, info, name, TRUE, copy, FALSE);
1566       else
1567 	h = bfd_link_hash_lookup (info->hash, name, TRUE, copy, FALSE);
1568       if (h == NULL)
1569 	{
1570 	  if (hashp != NULL)
1571 	    *hashp = NULL;
1572 	  return FALSE;
1573 	}
1574     }
1575 
1576   if (info->notice_all
1577       || (info->notice_hash != NULL
1578 	  && bfd_hash_lookup (info->notice_hash, name, FALSE, FALSE) != NULL))
1579     {
1580       if (! (*info->callbacks->notice) (info, h->root.string, abfd, section,
1581 					value))
1582 	return FALSE;
1583     }
1584 
1585   if (hashp != NULL)
1586     *hashp = h;
1587 
1588   do
1589     {
1590       enum link_action action;
1591 
1592       cycle = FALSE;
1593       action = link_action[(int) row][(int) h->type];
1594       switch (action)
1595 	{
1596 	case FAIL:
1597 	  abort ();
1598 
1599 	case NOACT:
1600 	  /* Do nothing.  */
1601 	  break;
1602 
1603 	case UND:
1604 	  /* Make a new undefined symbol.  */
1605 	  h->type = bfd_link_hash_undefined;
1606 	  h->u.undef.abfd = abfd;
1607 	  bfd_link_add_undef (info->hash, h);
1608 	  break;
1609 
1610 	case WEAK:
1611 	  /* Make a new weak undefined symbol.  */
1612 	  h->type = bfd_link_hash_undefweak;
1613 	  h->u.undef.abfd = abfd;
1614 	  h->u.undef.weak = abfd;
1615 	  break;
1616 
1617 	case CDEF:
1618 	  /* We have found a definition for a symbol which was
1619 	     previously common.  */
1620 	  BFD_ASSERT (h->type == bfd_link_hash_common);
1621 	  if (! ((*info->callbacks->multiple_common)
1622 		 (info, h->root.string,
1623 		  h->u.c.p->section->owner, bfd_link_hash_common, h->u.c.size,
1624 		  abfd, bfd_link_hash_defined, 0)))
1625 	    return FALSE;
1626 	  /* Fall through.  */
1627 	case DEF:
1628 	case DEFW:
1629 	  {
1630 	    enum bfd_link_hash_type oldtype;
1631 
1632 	    /* Define a symbol.  */
1633 	    oldtype = h->type;
1634 	    if (action == DEFW)
1635 	      h->type = bfd_link_hash_defweak;
1636 	    else
1637 	      h->type = bfd_link_hash_defined;
1638 	    h->u.def.section = section;
1639 	    h->u.def.value = value;
1640 
1641 	    /* If we have been asked to, we act like collect2 and
1642 	       identify all functions that might be global
1643 	       constructors and destructors and pass them up in a
1644 	       callback.  We only do this for certain object file
1645 	       types, since many object file types can handle this
1646 	       automatically.  */
1647 	    if (collect && name[0] == '_')
1648 	      {
1649 		const char *s;
1650 
1651 		/* A constructor or destructor name starts like this:
1652 		   _+GLOBAL_[_.$][ID][_.$] where the first [_.$] and
1653 		   the second are the same character (we accept any
1654 		   character there, in case a new object file format
1655 		   comes along with even worse naming restrictions).  */
1656 
1657 #define CONS_PREFIX "GLOBAL_"
1658 #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1)
1659 
1660 		s = name + 1;
1661 		while (*s == '_')
1662 		  ++s;
1663 		if (s[0] == 'G' && CONST_STRNEQ (s, CONS_PREFIX))
1664 		  {
1665 		    char c;
1666 
1667 		    c = s[CONS_PREFIX_LEN + 1];
1668 		    if ((c == 'I' || c == 'D')
1669 			&& s[CONS_PREFIX_LEN] == s[CONS_PREFIX_LEN + 2])
1670 		      {
1671 			/* If this is a definition of a symbol which
1672                            was previously weakly defined, we are in
1673                            trouble.  We have already added a
1674                            constructor entry for the weak defined
1675                            symbol, and now we are trying to add one
1676                            for the new symbol.  Fortunately, this case
1677                            should never arise in practice.  */
1678 			if (oldtype == bfd_link_hash_defweak)
1679 			  abort ();
1680 
1681 			if (! ((*info->callbacks->constructor)
1682 			       (info, c == 'I',
1683 				h->root.string, abfd, section, value)))
1684 			  return FALSE;
1685 		      }
1686 		  }
1687 	      }
1688 	  }
1689 
1690 	  break;
1691 
1692 	case COM:
1693 	  /* We have found a common definition for a symbol.  */
1694 	  if (h->type == bfd_link_hash_new)
1695 	    bfd_link_add_undef (info->hash, h);
1696 	  h->type = bfd_link_hash_common;
1697 	  h->u.c.p =
1698 	    bfd_hash_allocate (&info->hash->table,
1699 			       sizeof (struct bfd_link_hash_common_entry));
1700 	  if (h->u.c.p == NULL)
1701 	    return FALSE;
1702 
1703 	  h->u.c.size = value;
1704 
1705 	  /* Select a default alignment based on the size.  This may
1706              be overridden by the caller.  */
1707 	  {
1708 	    unsigned int power;
1709 
1710 	    power = bfd_log2 (value);
1711 	    if (power > 4)
1712 	      power = 4;
1713 	    h->u.c.p->alignment_power = power;
1714 	  }
1715 
1716 	  /* The section of a common symbol is only used if the common
1717              symbol is actually allocated.  It basically provides a
1718              hook for the linker script to decide which output section
1719              the common symbols should be put in.  In most cases, the
1720              section of a common symbol will be bfd_com_section_ptr,
1721              the code here will choose a common symbol section named
1722              "COMMON", and the linker script will contain *(COMMON) in
1723              the appropriate place.  A few targets use separate common
1724              sections for small symbols, and they require special
1725              handling.  */
1726 	  if (section == bfd_com_section_ptr)
1727 	    {
1728 	      h->u.c.p->section = bfd_make_section_old_way (abfd, "COMMON");
1729 	      h->u.c.p->section->flags = SEC_ALLOC;
1730 	    }
1731 	  else if (section->owner != abfd)
1732 	    {
1733 	      h->u.c.p->section = bfd_make_section_old_way (abfd,
1734 							    section->name);
1735 	      h->u.c.p->section->flags = SEC_ALLOC;
1736 	    }
1737 	  else
1738 	    h->u.c.p->section = section;
1739 	  break;
1740 
1741 	case REF:
1742 	  /* A reference to a defined symbol.  */
1743 	  if (h->u.undef.next == NULL && info->hash->undefs_tail != h)
1744 	    h->u.undef.next = h;
1745 	  break;
1746 
1747 	case BIG:
1748 	  /* We have found a common definition for a symbol which
1749 	     already had a common definition.  Use the maximum of the
1750 	     two sizes, and use the section required by the larger symbol.  */
1751 	  BFD_ASSERT (h->type == bfd_link_hash_common);
1752 	  if (! ((*info->callbacks->multiple_common)
1753 		 (info, h->root.string,
1754 		  h->u.c.p->section->owner, bfd_link_hash_common, h->u.c.size,
1755 		  abfd, bfd_link_hash_common, value)))
1756 	    return FALSE;
1757 	  if (value > h->u.c.size)
1758 	    {
1759 	      unsigned int power;
1760 
1761 	      h->u.c.size = value;
1762 
1763 	      /* Select a default alignment based on the size.  This may
1764 		 be overridden by the caller.  */
1765 	      power = bfd_log2 (value);
1766 	      if (power > 4)
1767 		power = 4;
1768 	      h->u.c.p->alignment_power = power;
1769 
1770 	      /* Some systems have special treatment for small commons,
1771 		 hence we want to select the section used by the larger
1772 		 symbol.  This makes sure the symbol does not go in a
1773 		 small common section if it is now too large.  */
1774 	      if (section == bfd_com_section_ptr)
1775 		{
1776 		  h->u.c.p->section
1777 		    = bfd_make_section_old_way (abfd, "COMMON");
1778 		  h->u.c.p->section->flags = SEC_ALLOC;
1779 		}
1780 	      else if (section->owner != abfd)
1781 		{
1782 		  h->u.c.p->section
1783 		    = bfd_make_section_old_way (abfd, section->name);
1784 		  h->u.c.p->section->flags = SEC_ALLOC;
1785 		}
1786 	      else
1787 		h->u.c.p->section = section;
1788 	    }
1789 	  break;
1790 
1791 	case CREF:
1792 	  {
1793 	    bfd *obfd;
1794 
1795 	    /* We have found a common definition for a symbol which
1796 	       was already defined.  FIXME: It would nice if we could
1797 	       report the BFD which defined an indirect symbol, but we
1798 	       don't have anywhere to store the information.  */
1799 	    if (h->type == bfd_link_hash_defined
1800 		|| h->type == bfd_link_hash_defweak)
1801 	      obfd = h->u.def.section->owner;
1802 	    else
1803 	      obfd = NULL;
1804 	    if (! ((*info->callbacks->multiple_common)
1805 		   (info, h->root.string, obfd, h->type, 0,
1806 		    abfd, bfd_link_hash_common, value)))
1807 	      return FALSE;
1808 	  }
1809 	  break;
1810 
1811 	case MIND:
1812 	  /* Multiple indirect symbols.  This is OK if they both point
1813 	     to the same symbol.  */
1814 	  if (strcmp (h->u.i.link->root.string, string) == 0)
1815 	    break;
1816 	  /* Fall through.  */
1817 	case MDEF:
1818 	  /* Handle a multiple definition.  */
1819 	  if (!info->allow_multiple_definition)
1820 	    {
1821 	      asection *msec = NULL;
1822 	      bfd_vma mval = 0;
1823 
1824 	      switch (h->type)
1825 		{
1826 		case bfd_link_hash_defined:
1827 		  msec = h->u.def.section;
1828 		  mval = h->u.def.value;
1829 		  break;
1830 	        case bfd_link_hash_indirect:
1831 		  msec = bfd_ind_section_ptr;
1832 		  mval = 0;
1833 		  break;
1834 		default:
1835 		  abort ();
1836 		}
1837 
1838 	      /* Ignore a redefinition of an absolute symbol to the
1839 		 same value; it's harmless.  */
1840 	      if (h->type == bfd_link_hash_defined
1841 		  && bfd_is_abs_section (msec)
1842 		  && bfd_is_abs_section (section)
1843 		  && value == mval)
1844 		break;
1845 
1846 	      if (! ((*info->callbacks->multiple_definition)
1847 		     (info, h->root.string, msec->owner, msec, mval,
1848 		      abfd, section, value)))
1849 		return FALSE;
1850 	    }
1851 	  break;
1852 
1853 	case CIND:
1854 	  /* Create an indirect symbol from an existing common symbol.  */
1855 	  BFD_ASSERT (h->type == bfd_link_hash_common);
1856 	  if (! ((*info->callbacks->multiple_common)
1857 		 (info, h->root.string,
1858 		  h->u.c.p->section->owner, bfd_link_hash_common, h->u.c.size,
1859 		  abfd, bfd_link_hash_indirect, 0)))
1860 	    return FALSE;
1861 	  /* Fall through.  */
1862 	case IND:
1863 	  /* Create an indirect symbol.  */
1864 	  {
1865 	    struct bfd_link_hash_entry *inh;
1866 
1867 	    /* STRING is the name of the symbol we want to indirect
1868 	       to.  */
1869 	    inh = bfd_wrapped_link_hash_lookup (abfd, info, string, TRUE,
1870 						copy, FALSE);
1871 	    if (inh == NULL)
1872 	      return FALSE;
1873 	    if (inh->type == bfd_link_hash_indirect
1874 		&& inh->u.i.link == h)
1875 	      {
1876 		(*_bfd_error_handler)
1877 		  (_("%B: indirect symbol `%s' to `%s' is a loop"),
1878 		   abfd, name, string);
1879 		bfd_set_error (bfd_error_invalid_operation);
1880 		return FALSE;
1881 	      }
1882 	    if (inh->type == bfd_link_hash_new)
1883 	      {
1884 		inh->type = bfd_link_hash_undefined;
1885 		inh->u.undef.abfd = abfd;
1886 		bfd_link_add_undef (info->hash, inh);
1887 	      }
1888 
1889 	    /* If the indirect symbol has been referenced, we need to
1890 	       push the reference down to the symbol we are
1891 	       referencing.  */
1892 	    if (h->type != bfd_link_hash_new)
1893 	      {
1894 		row = UNDEF_ROW;
1895 		cycle = TRUE;
1896 	      }
1897 
1898 	    h->type = bfd_link_hash_indirect;
1899 	    h->u.i.link = inh;
1900 	  }
1901 	  break;
1902 
1903 	case SET:
1904 	  /* Add an entry to a set.  */
1905 	  if (! (*info->callbacks->add_to_set) (info, h, BFD_RELOC_CTOR,
1906 						abfd, section, value))
1907 	    return FALSE;
1908 	  break;
1909 
1910 	case WARNC:
1911 	  /* Issue a warning and cycle.  */
1912 	  if (h->u.i.warning != NULL)
1913 	    {
1914 	      if (! (*info->callbacks->warning) (info, h->u.i.warning,
1915 						 h->root.string, abfd,
1916 						 NULL, 0))
1917 		return FALSE;
1918 	      /* Only issue a warning once.  */
1919 	      h->u.i.warning = NULL;
1920 	    }
1921 	  /* Fall through.  */
1922 	case CYCLE:
1923 	  /* Try again with the referenced symbol.  */
1924 	  h = h->u.i.link;
1925 	  cycle = TRUE;
1926 	  break;
1927 
1928 	case REFC:
1929 	  /* A reference to an indirect symbol.  */
1930 	  if (h->u.undef.next == NULL && info->hash->undefs_tail != h)
1931 	    h->u.undef.next = h;
1932 	  h = h->u.i.link;
1933 	  cycle = TRUE;
1934 	  break;
1935 
1936 	case WARN:
1937 	  /* Issue a warning.  */
1938 	  if (! (*info->callbacks->warning) (info, string, h->root.string,
1939 					     hash_entry_bfd (h), NULL, 0))
1940 	    return FALSE;
1941 	  break;
1942 
1943 	case CWARN:
1944 	  /* Warn if this symbol has been referenced already,
1945 	     otherwise add a warning.  A symbol has been referenced if
1946 	     the u.undef.next field is not NULL, or it is the tail of the
1947 	     undefined symbol list.  The REF case above helps to
1948 	     ensure this.  */
1949 	  if (h->u.undef.next != NULL || info->hash->undefs_tail == h)
1950 	    {
1951 	      if (! (*info->callbacks->warning) (info, string, h->root.string,
1952 						 hash_entry_bfd (h), NULL, 0))
1953 		return FALSE;
1954 	      break;
1955 	    }
1956 	  /* Fall through.  */
1957 	case MWARN:
1958 	  /* Make a warning symbol.  */
1959 	  {
1960 	    struct bfd_link_hash_entry *sub;
1961 
1962 	    /* STRING is the warning to give.  */
1963 	    sub = ((struct bfd_link_hash_entry *)
1964 		   ((*info->hash->table.newfunc)
1965 		    (NULL, &info->hash->table, h->root.string)));
1966 	    if (sub == NULL)
1967 	      return FALSE;
1968 	    *sub = *h;
1969 	    sub->type = bfd_link_hash_warning;
1970 	    sub->u.i.link = h;
1971 	    if (! copy)
1972 	      sub->u.i.warning = string;
1973 	    else
1974 	      {
1975 		char *w;
1976 		size_t len = strlen (string) + 1;
1977 
1978 		w = bfd_hash_allocate (&info->hash->table, len);
1979 		if (w == NULL)
1980 		  return FALSE;
1981 		memcpy (w, string, len);
1982 		sub->u.i.warning = w;
1983 	      }
1984 
1985 	    bfd_hash_replace (&info->hash->table,
1986 			      (struct bfd_hash_entry *) h,
1987 			      (struct bfd_hash_entry *) sub);
1988 	    if (hashp != NULL)
1989 	      *hashp = sub;
1990 	  }
1991 	  break;
1992 	}
1993     }
1994   while (cycle);
1995 
1996   return TRUE;
1997 }
1998 
1999 /* Generic final link routine.  */
2000 
2001 bfd_boolean
_bfd_generic_final_link(bfd * abfd,struct bfd_link_info * info)2002 _bfd_generic_final_link (bfd *abfd, struct bfd_link_info *info)
2003 {
2004   bfd *sub;
2005   asection *o;
2006   struct bfd_link_order *p;
2007   size_t outsymalloc;
2008   struct generic_write_global_symbol_info wginfo;
2009 
2010   bfd_get_outsymbols (abfd) = NULL;
2011   bfd_get_symcount (abfd) = 0;
2012   outsymalloc = 0;
2013 
2014   /* Mark all sections which will be included in the output file.  */
2015   for (o = abfd->sections; o != NULL; o = o->next)
2016     for (p = o->map_head.link_order; p != NULL; p = p->next)
2017       if (p->type == bfd_indirect_link_order)
2018 	p->u.indirect.section->linker_mark = TRUE;
2019 
2020   /* Build the output symbol table.  */
2021   for (sub = info->input_bfds; sub != NULL; sub = sub->link_next)
2022     if (! _bfd_generic_link_output_symbols (abfd, sub, info, &outsymalloc))
2023       return FALSE;
2024 
2025   /* Accumulate the global symbols.  */
2026   wginfo.info = info;
2027   wginfo.output_bfd = abfd;
2028   wginfo.psymalloc = &outsymalloc;
2029   _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info),
2030 				   _bfd_generic_link_write_global_symbol,
2031 				   &wginfo);
2032 
2033   /* Make sure we have a trailing NULL pointer on OUTSYMBOLS.  We
2034      shouldn't really need one, since we have SYMCOUNT, but some old
2035      code still expects one.  */
2036   if (! generic_add_output_symbol (abfd, &outsymalloc, NULL))
2037     return FALSE;
2038 
2039   if (info->relocatable)
2040     {
2041       /* Allocate space for the output relocs for each section.  */
2042       for (o = abfd->sections; o != NULL; o = o->next)
2043 	{
2044 	  o->reloc_count = 0;
2045 	  for (p = o->map_head.link_order; p != NULL; p = p->next)
2046 	    {
2047 	      if (p->type == bfd_section_reloc_link_order
2048 		  || p->type == bfd_symbol_reloc_link_order)
2049 		++o->reloc_count;
2050 	      else if (p->type == bfd_indirect_link_order)
2051 		{
2052 		  asection *input_section;
2053 		  bfd *input_bfd;
2054 		  long relsize;
2055 		  arelent **relocs;
2056 		  asymbol **symbols;
2057 		  long reloc_count;
2058 
2059 		  input_section = p->u.indirect.section;
2060 		  input_bfd = input_section->owner;
2061 		  relsize = bfd_get_reloc_upper_bound (input_bfd,
2062 						       input_section);
2063 		  if (relsize < 0)
2064 		    return FALSE;
2065 		  relocs = bfd_malloc (relsize);
2066 		  if (!relocs && relsize != 0)
2067 		    return FALSE;
2068 		  symbols = _bfd_generic_link_get_symbols (input_bfd);
2069 		  reloc_count = bfd_canonicalize_reloc (input_bfd,
2070 							input_section,
2071 							relocs,
2072 							symbols);
2073 		  free (relocs);
2074 		  if (reloc_count < 0)
2075 		    return FALSE;
2076 		  BFD_ASSERT ((unsigned long) reloc_count
2077 			      == input_section->reloc_count);
2078 		  o->reloc_count += reloc_count;
2079 		}
2080 	    }
2081 	  if (o->reloc_count > 0)
2082 	    {
2083 	      bfd_size_type amt;
2084 
2085 	      amt = o->reloc_count;
2086 	      amt *= sizeof (arelent *);
2087 	      o->orelocation = bfd_alloc (abfd, amt);
2088 	      if (!o->orelocation)
2089 		return FALSE;
2090 	      o->flags |= SEC_RELOC;
2091 	      /* Reset the count so that it can be used as an index
2092 		 when putting in the output relocs.  */
2093 	      o->reloc_count = 0;
2094 	    }
2095 	}
2096     }
2097 
2098   /* Handle all the link order information for the sections.  */
2099   for (o = abfd->sections; o != NULL; o = o->next)
2100     {
2101       for (p = o->map_head.link_order; p != NULL; p = p->next)
2102 	{
2103 	  switch (p->type)
2104 	    {
2105 	    case bfd_section_reloc_link_order:
2106 	    case bfd_symbol_reloc_link_order:
2107 	      if (! _bfd_generic_reloc_link_order (abfd, info, o, p))
2108 		return FALSE;
2109 	      break;
2110 	    case bfd_indirect_link_order:
2111 	      if (! default_indirect_link_order (abfd, info, o, p, TRUE))
2112 		return FALSE;
2113 	      break;
2114 	    default:
2115 	      if (! _bfd_default_link_order (abfd, info, o, p))
2116 		return FALSE;
2117 	      break;
2118 	    }
2119 	}
2120     }
2121 
2122   return TRUE;
2123 }
2124 
2125 /* Add an output symbol to the output BFD.  */
2126 
2127 static bfd_boolean
generic_add_output_symbol(bfd * output_bfd,size_t * psymalloc,asymbol * sym)2128 generic_add_output_symbol (bfd *output_bfd, size_t *psymalloc, asymbol *sym)
2129 {
2130   if (bfd_get_symcount (output_bfd) >= *psymalloc)
2131     {
2132       asymbol **newsyms;
2133       bfd_size_type amt;
2134 
2135       if (*psymalloc == 0)
2136 	*psymalloc = 124;
2137       else
2138 	*psymalloc *= 2;
2139       amt = *psymalloc;
2140       amt *= sizeof (asymbol *);
2141       newsyms = bfd_realloc (bfd_get_outsymbols (output_bfd), amt);
2142       if (newsyms == NULL)
2143 	return FALSE;
2144       bfd_get_outsymbols (output_bfd) = newsyms;
2145     }
2146 
2147   bfd_get_outsymbols (output_bfd) [bfd_get_symcount (output_bfd)] = sym;
2148   if (sym != NULL)
2149     ++ bfd_get_symcount (output_bfd);
2150 
2151   return TRUE;
2152 }
2153 
2154 /* Handle the symbols for an input BFD.  */
2155 
2156 bfd_boolean
_bfd_generic_link_output_symbols(bfd * output_bfd,bfd * input_bfd,struct bfd_link_info * info,size_t * psymalloc)2157 _bfd_generic_link_output_symbols (bfd *output_bfd,
2158 				  bfd *input_bfd,
2159 				  struct bfd_link_info *info,
2160 				  size_t *psymalloc)
2161 {
2162   asymbol **sym_ptr;
2163   asymbol **sym_end;
2164 
2165   if (! generic_link_read_symbols (input_bfd))
2166     return FALSE;
2167 
2168   /* Create a filename symbol if we are supposed to.  */
2169   if (info->create_object_symbols_section != NULL)
2170     {
2171       asection *sec;
2172 
2173       for (sec = input_bfd->sections; sec != NULL; sec = sec->next)
2174 	{
2175 	  if (sec->output_section == info->create_object_symbols_section)
2176 	    {
2177 	      asymbol *newsym;
2178 
2179 	      newsym = bfd_make_empty_symbol (input_bfd);
2180 	      if (!newsym)
2181 		return FALSE;
2182 	      newsym->name = input_bfd->filename;
2183 	      newsym->value = 0;
2184 	      newsym->flags = BSF_LOCAL | BSF_FILE;
2185 	      newsym->section = sec;
2186 
2187 	      if (! generic_add_output_symbol (output_bfd, psymalloc,
2188 					       newsym))
2189 		return FALSE;
2190 
2191 	      break;
2192 	    }
2193 	}
2194     }
2195 
2196   /* Adjust the values of the globally visible symbols, and write out
2197      local symbols.  */
2198   sym_ptr = _bfd_generic_link_get_symbols (input_bfd);
2199   sym_end = sym_ptr + _bfd_generic_link_get_symcount (input_bfd);
2200   for (; sym_ptr < sym_end; sym_ptr++)
2201     {
2202       asymbol *sym;
2203       struct generic_link_hash_entry *h;
2204       bfd_boolean output;
2205 
2206       h = NULL;
2207       sym = *sym_ptr;
2208       if ((sym->flags & (BSF_INDIRECT
2209 			 | BSF_WARNING
2210 			 | BSF_GLOBAL
2211 			 | BSF_CONSTRUCTOR
2212 			 | BSF_WEAK)) != 0
2213 	  || bfd_is_und_section (bfd_get_section (sym))
2214 	  || bfd_is_com_section (bfd_get_section (sym))
2215 	  || bfd_is_ind_section (bfd_get_section (sym)))
2216 	{
2217 	  if (sym->udata.p != NULL)
2218 	    h = sym->udata.p;
2219 	  else if ((sym->flags & BSF_CONSTRUCTOR) != 0)
2220 	    {
2221 	      /* This case normally means that the main linker code
2222                  deliberately ignored this constructor symbol.  We
2223                  should just pass it through.  This will screw up if
2224                  the constructor symbol is from a different,
2225                  non-generic, object file format, but the case will
2226                  only arise when linking with -r, which will probably
2227                  fail anyhow, since there will be no way to represent
2228                  the relocs in the output format being used.  */
2229 	      h = NULL;
2230 	    }
2231 	  else if (bfd_is_und_section (bfd_get_section (sym)))
2232 	    h = ((struct generic_link_hash_entry *)
2233 		 bfd_wrapped_link_hash_lookup (output_bfd, info,
2234 					       bfd_asymbol_name (sym),
2235 					       FALSE, FALSE, TRUE));
2236 	  else
2237 	    h = _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info),
2238 					       bfd_asymbol_name (sym),
2239 					       FALSE, FALSE, TRUE);
2240 
2241 	  if (h != NULL)
2242 	    {
2243 	      /* Force all references to this symbol to point to
2244 		 the same area in memory.  It is possible that
2245 		 this routine will be called with a hash table
2246 		 other than a generic hash table, so we double
2247 		 check that.  */
2248 	      if (info->hash->creator == input_bfd->xvec)
2249 		{
2250 		  if (h->sym != NULL)
2251 		    *sym_ptr = sym = h->sym;
2252 		}
2253 
2254 	      switch (h->root.type)
2255 		{
2256 		default:
2257 		case bfd_link_hash_new:
2258 		  abort ();
2259 		case bfd_link_hash_undefined:
2260 		  break;
2261 		case bfd_link_hash_undefweak:
2262 		  sym->flags |= BSF_WEAK;
2263 		  break;
2264 		case bfd_link_hash_indirect:
2265 		  h = (struct generic_link_hash_entry *) h->root.u.i.link;
2266 		  /* fall through */
2267 		case bfd_link_hash_defined:
2268 		  sym->flags |= BSF_GLOBAL;
2269 		  sym->flags &=~ BSF_CONSTRUCTOR;
2270 		  sym->value = h->root.u.def.value;
2271 		  sym->section = h->root.u.def.section;
2272 		  break;
2273 		case bfd_link_hash_defweak:
2274 		  sym->flags |= BSF_WEAK;
2275 		  sym->flags &=~ BSF_CONSTRUCTOR;
2276 		  sym->value = h->root.u.def.value;
2277 		  sym->section = h->root.u.def.section;
2278 		  break;
2279 		case bfd_link_hash_common:
2280 		  sym->value = h->root.u.c.size;
2281 		  sym->flags |= BSF_GLOBAL;
2282 		  if (! bfd_is_com_section (sym->section))
2283 		    {
2284 		      BFD_ASSERT (bfd_is_und_section (sym->section));
2285 		      sym->section = bfd_com_section_ptr;
2286 		    }
2287 		  /* We do not set the section of the symbol to
2288 		     h->root.u.c.p->section.  That value was saved so
2289 		     that we would know where to allocate the symbol
2290 		     if it was defined.  In this case the type is
2291 		     still bfd_link_hash_common, so we did not define
2292 		     it, so we do not want to use that section.  */
2293 		  break;
2294 		}
2295 	    }
2296 	}
2297 
2298       /* This switch is straight from the old code in
2299 	 write_file_locals in ldsym.c.  */
2300       if (info->strip == strip_all
2301 	  || (info->strip == strip_some
2302 	      && bfd_hash_lookup (info->keep_hash, bfd_asymbol_name (sym),
2303 				  FALSE, FALSE) == NULL))
2304 	output = FALSE;
2305       else if ((sym->flags & (BSF_GLOBAL | BSF_WEAK)) != 0)
2306 	{
2307 	  /* If this symbol is marked as occurring now, rather
2308 	     than at the end, output it now.  This is used for
2309 	     COFF C_EXT FCN symbols.  FIXME: There must be a
2310 	     better way.  */
2311 	  if (bfd_asymbol_bfd (sym) == input_bfd
2312 	      && (sym->flags & BSF_NOT_AT_END) != 0)
2313 	    output = TRUE;
2314 	  else
2315 	    output = FALSE;
2316 	}
2317       else if (bfd_is_ind_section (sym->section))
2318 	output = FALSE;
2319       else if ((sym->flags & BSF_DEBUGGING) != 0)
2320 	{
2321 	  if (info->strip == strip_none)
2322 	    output = TRUE;
2323 	  else
2324 	    output = FALSE;
2325 	}
2326       else if (bfd_is_und_section (sym->section)
2327 	       || bfd_is_com_section (sym->section))
2328 	output = FALSE;
2329       else if ((sym->flags & BSF_LOCAL) != 0)
2330 	{
2331 	  if ((sym->flags & BSF_WARNING) != 0)
2332 	    output = FALSE;
2333 	  else
2334 	    {
2335 	      switch (info->discard)
2336 		{
2337 		default:
2338 		case discard_all:
2339 		  output = FALSE;
2340 		  break;
2341 		case discard_sec_merge:
2342 		  output = TRUE;
2343 		  if (info->relocatable
2344 		      || ! (sym->section->flags & SEC_MERGE))
2345 		    break;
2346 		  /* FALLTHROUGH */
2347 		case discard_l:
2348 		  if (bfd_is_local_label (input_bfd, sym))
2349 		    output = FALSE;
2350 		  else
2351 		    output = TRUE;
2352 		  break;
2353 		case discard_none:
2354 		  output = TRUE;
2355 		  break;
2356 		}
2357 	    }
2358 	}
2359       else if ((sym->flags & BSF_CONSTRUCTOR))
2360 	{
2361 	  if (info->strip != strip_all)
2362 	    output = TRUE;
2363 	  else
2364 	    output = FALSE;
2365 	}
2366       else
2367 	abort ();
2368 
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
2371 	 symbol.  */
2372       if (!bfd_is_abs_section (sym->section)
2373 	  && bfd_section_removed_from_list (output_bfd,
2374 					    sym->section->output_section))
2375 	output = FALSE;
2376 
2377       if (output)
2378 	{
2379 	  if (! generic_add_output_symbol (output_bfd, psymalloc, sym))
2380 	    return FALSE;
2381 	  if (h != NULL)
2382 	    h->written = TRUE;
2383 	}
2384     }
2385 
2386   return TRUE;
2387 }
2388 
2389 /* Set the section and value of a generic BFD symbol based on a linker
2390    hash table entry.  */
2391 
2392 static void
set_symbol_from_hash(asymbol * sym,struct bfd_link_hash_entry * h)2393 set_symbol_from_hash (asymbol *sym, struct bfd_link_hash_entry *h)
2394 {
2395   switch (h->type)
2396     {
2397     default:
2398       abort ();
2399       break;
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)
2404 	{
2405 	  BFD_ASSERT ((sym->flags & BSF_CONSTRUCTOR) != 0);
2406 	}
2407       else
2408 	{
2409 	  sym->flags |= BSF_CONSTRUCTOR;
2410 	  sym->section = bfd_abs_section_ptr;
2411 	  sym->value = 0;
2412 	}
2413       break;
2414     case bfd_link_hash_undefined:
2415       sym->section = bfd_und_section_ptr;
2416       sym->value = 0;
2417       break;
2418     case bfd_link_hash_undefweak:
2419       sym->section = bfd_und_section_ptr;
2420       sym->value = 0;
2421       sym->flags |= BSF_WEAK;
2422       break;
2423     case bfd_link_hash_defined:
2424       sym->section = h->u.def.section;
2425       sym->value = h->u.def.value;
2426       break;
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;
2431       break;
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))
2437 	{
2438 	  BFD_ASSERT (bfd_is_und_section (sym->section));
2439 	  sym->section = bfd_com_section_ptr;
2440 	}
2441       /* Do not set the section; see _bfd_generic_link_output_symbols.  */
2442       break;
2443     case bfd_link_hash_indirect:
2444     case bfd_link_hash_warning:
2445       /* FIXME: What should we do here?  */
2446       break;
2447     }
2448 }
2449 
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.  */
2452 
2453 bfd_boolean
_bfd_generic_link_write_global_symbol(struct generic_link_hash_entry * h,void * data)2454 _bfd_generic_link_write_global_symbol (struct generic_link_hash_entry *h,
2455 				       void *data)
2456 {
2457   struct generic_write_global_symbol_info *wginfo = data;
2458   asymbol *sym;
2459 
2460   if (h->root.type == bfd_link_hash_warning)
2461     h = (struct generic_link_hash_entry *) h->root.u.i.link;
2462 
2463   if (h->written)
2464     return TRUE;
2465 
2466   h->written = TRUE;
2467 
2468   if (wginfo->info->strip == strip_all
2469       || (wginfo->info->strip == strip_some
2470 	  && bfd_hash_lookup (wginfo->info->keep_hash, h->root.root.string,
2471 			      FALSE, FALSE) == NULL))
2472     return TRUE;
2473 
2474   if (h->sym != NULL)
2475     sym = h->sym;
2476   else
2477     {
2478       sym = bfd_make_empty_symbol (wginfo->output_bfd);
2479       if (!sym)
2480 	return FALSE;
2481       sym->name = h->root.root.string;
2482       sym->flags = 0;
2483     }
2484 
2485   set_symbol_from_hash (sym, &h->root);
2486 
2487   sym->flags |= BSF_GLOBAL;
2488 
2489   if (! generic_add_output_symbol (wginfo->output_bfd, wginfo->psymalloc,
2490 				   sym))
2491     {
2492       /* FIXME: No way to return failure.  */
2493       abort ();
2494     }
2495 
2496   return TRUE;
2497 }
2498 
2499 /* Create a relocation.  */
2500 
2501 bfd_boolean
_bfd_generic_reloc_link_order(bfd * abfd,struct bfd_link_info * info,asection * sec,struct bfd_link_order * link_order)2502 _bfd_generic_reloc_link_order (bfd *abfd,
2503 			       struct bfd_link_info *info,
2504 			       asection *sec,
2505 			       struct bfd_link_order *link_order)
2506 {
2507   arelent *r;
2508 
2509   if (! info->relocatable)
2510     abort ();
2511   if (sec->orelocation == NULL)
2512     abort ();
2513 
2514   r = bfd_alloc (abfd, sizeof (arelent));
2515   if (r == NULL)
2516     return FALSE;
2517 
2518   r->address = link_order->offset;
2519   r->howto = bfd_reloc_type_lookup (abfd, link_order->u.reloc.p->reloc);
2520   if (r->howto == 0)
2521     {
2522       bfd_set_error (bfd_error_bad_value);
2523       return FALSE;
2524     }
2525 
2526   /* Get the symbol to use for the relocation.  */
2527   if (link_order->type == bfd_section_reloc_link_order)
2528     r->sym_ptr_ptr = link_order->u.reloc.p->u.section->symbol_ptr_ptr;
2529   else
2530     {
2531       struct generic_link_hash_entry *h;
2532 
2533       h = ((struct generic_link_hash_entry *)
2534 	   bfd_wrapped_link_hash_lookup (abfd, info,
2535 					 link_order->u.reloc.p->u.name,
2536 					 FALSE, FALSE, TRUE));
2537       if (h == NULL
2538 	  || ! h->written)
2539 	{
2540 	  if (! ((*info->callbacks->unattached_reloc)
2541 		 (info, link_order->u.reloc.p->u.name, NULL, NULL, 0)))
2542 	    return FALSE;
2543 	  bfd_set_error (bfd_error_bad_value);
2544 	  return FALSE;
2545 	}
2546       r->sym_ptr_ptr = &h->sym;
2547     }
2548 
2549   /* If this is an inplace reloc, write the addend to the object file.
2550      Otherwise, store it in the reloc addend.  */
2551   if (! r->howto->partial_inplace)
2552     r->addend = link_order->u.reloc.p->addend;
2553   else
2554     {
2555       bfd_size_type size;
2556       bfd_reloc_status_type rstat;
2557       bfd_byte *buf;
2558       bfd_boolean ok;
2559       file_ptr loc;
2560 
2561       size = bfd_get_reloc_size (r->howto);
2562       buf = bfd_zmalloc (size);
2563       if (buf == NULL)
2564 	return FALSE;
2565       rstat = _bfd_relocate_contents (r->howto, abfd,
2566 				      (bfd_vma) link_order->u.reloc.p->addend,
2567 				      buf);
2568       switch (rstat)
2569 	{
2570 	case bfd_reloc_ok:
2571 	  break;
2572 	default:
2573 	case bfd_reloc_outofrange:
2574 	  abort ();
2575 	case bfd_reloc_overflow:
2576 	  if (! ((*info->callbacks->reloc_overflow)
2577 		 (info, NULL,
2578 		  (link_order->type == bfd_section_reloc_link_order
2579 		   ? bfd_section_name (abfd, link_order->u.reloc.p->u.section)
2580 		   : link_order->u.reloc.p->u.name),
2581 		  r->howto->name, link_order->u.reloc.p->addend,
2582 		  NULL, NULL, 0)))
2583 	    {
2584 	      free (buf);
2585 	      return FALSE;
2586 	    }
2587 	  break;
2588 	}
2589       loc = link_order->offset * bfd_octets_per_byte (abfd);
2590       ok = bfd_set_section_contents (abfd, sec, buf, loc, size);
2591       free (buf);
2592       if (! ok)
2593 	return FALSE;
2594 
2595       r->addend = 0;
2596     }
2597 
2598   sec->orelocation[sec->reloc_count] = r;
2599   ++sec->reloc_count;
2600 
2601   return TRUE;
2602 }
2603 
2604 /* Allocate a new link_order for a section.  */
2605 
2606 struct bfd_link_order *
bfd_new_link_order(bfd * abfd,asection * section)2607 bfd_new_link_order (bfd *abfd, asection *section)
2608 {
2609   bfd_size_type amt = sizeof (struct bfd_link_order);
2610   struct bfd_link_order *new;
2611 
2612   new = bfd_zalloc (abfd, amt);
2613   if (!new)
2614     return NULL;
2615 
2616   new->type = bfd_undefined_link_order;
2617 
2618   if (section->map_tail.link_order != NULL)
2619     section->map_tail.link_order->next = new;
2620   else
2621     section->map_head.link_order = new;
2622   section->map_tail.link_order = new;
2623 
2624   return new;
2625 }
2626 
2627 /* Default link order processing routine.  Note that we can not handle
2628    the reloc_link_order types here, since they depend upon the details
2629    of how the particular backends generates relocs.  */
2630 
2631 bfd_boolean
_bfd_default_link_order(bfd * abfd,struct bfd_link_info * info,asection * sec,struct bfd_link_order * link_order)2632 _bfd_default_link_order (bfd *abfd,
2633 			 struct bfd_link_info *info,
2634 			 asection *sec,
2635 			 struct bfd_link_order *link_order)
2636 {
2637   switch (link_order->type)
2638     {
2639     case bfd_undefined_link_order:
2640     case bfd_section_reloc_link_order:
2641     case bfd_symbol_reloc_link_order:
2642     default:
2643       abort ();
2644     case bfd_indirect_link_order:
2645       return default_indirect_link_order (abfd, info, sec, link_order,
2646 					  FALSE);
2647     case bfd_data_link_order:
2648       return default_data_link_order (abfd, info, sec, link_order);
2649     }
2650 }
2651 
2652 /* Default routine to handle a bfd_data_link_order.  */
2653 
2654 static bfd_boolean
default_data_link_order(bfd * abfd,struct bfd_link_info * info ATTRIBUTE_UNUSED,asection * sec,struct bfd_link_order * link_order)2655 default_data_link_order (bfd *abfd,
2656 			 struct bfd_link_info *info ATTRIBUTE_UNUSED,
2657 			 asection *sec,
2658 			 struct bfd_link_order *link_order)
2659 {
2660   bfd_size_type size;
2661   size_t fill_size;
2662   bfd_byte *fill;
2663   file_ptr loc;
2664   bfd_boolean result;
2665 
2666   BFD_ASSERT ((sec->flags & SEC_HAS_CONTENTS) != 0);
2667 
2668   size = link_order->size;
2669   if (size == 0)
2670     return TRUE;
2671 
2672   fill = link_order->u.data.contents;
2673   fill_size = link_order->u.data.size;
2674   if (fill_size != 0 && fill_size < size)
2675     {
2676       bfd_byte *p;
2677       fill = bfd_malloc (size);
2678       if (fill == NULL)
2679 	return FALSE;
2680       p = fill;
2681       if (fill_size == 1)
2682 	memset (p, (int) link_order->u.data.contents[0], (size_t) size);
2683       else
2684 	{
2685 	  do
2686 	    {
2687 	      memcpy (p, link_order->u.data.contents, fill_size);
2688 	      p += fill_size;
2689 	      size -= fill_size;
2690 	    }
2691 	  while (size >= fill_size);
2692 	  if (size != 0)
2693 	    memcpy (p, link_order->u.data.contents, (size_t) size);
2694 	  size = link_order->size;
2695 	}
2696     }
2697 
2698   loc = link_order->offset * bfd_octets_per_byte (abfd);
2699   result = bfd_set_section_contents (abfd, sec, fill, loc, size);
2700 
2701   if (fill != link_order->u.data.contents)
2702     free (fill);
2703   return result;
2704 }
2705 
2706 /* Default routine to handle a bfd_indirect_link_order.  */
2707 
2708 static bfd_boolean
default_indirect_link_order(bfd * output_bfd,struct bfd_link_info * info,asection * output_section,struct bfd_link_order * link_order,bfd_boolean generic_linker)2709 default_indirect_link_order (bfd *output_bfd,
2710 			     struct bfd_link_info *info,
2711 			     asection *output_section,
2712 			     struct bfd_link_order *link_order,
2713 			     bfd_boolean generic_linker)
2714 {
2715   asection *input_section;
2716   bfd *input_bfd;
2717   bfd_byte *contents = NULL;
2718   bfd_byte *new_contents;
2719   bfd_size_type sec_size;
2720   file_ptr loc;
2721 
2722   BFD_ASSERT ((output_section->flags & SEC_HAS_CONTENTS) != 0);
2723 
2724   input_section = link_order->u.indirect.section;
2725   input_bfd = input_section->owner;
2726   if (input_section->size == 0)
2727     return TRUE;
2728 
2729   BFD_ASSERT (input_section->output_section == output_section);
2730   BFD_ASSERT (input_section->output_offset == link_order->offset);
2731   BFD_ASSERT (input_section->size == link_order->size);
2732 
2733   if (info->relocatable
2734       && input_section->reloc_count > 0
2735       && output_section->orelocation == NULL)
2736     {
2737       /* Space has not been allocated for the output relocations.
2738 	 This can happen when we are called by a specific backend
2739 	 because somebody is attempting to link together different
2740 	 types of object files.  Handling this case correctly is
2741 	 difficult, and sometimes impossible.  */
2742       (*_bfd_error_handler)
2743 	(_("Attempt to do relocatable link with %s input and %s output"),
2744 	 bfd_get_target (input_bfd), bfd_get_target (output_bfd));
2745       bfd_set_error (bfd_error_wrong_format);
2746       return FALSE;
2747     }
2748 
2749   if (! generic_linker)
2750     {
2751       asymbol **sympp;
2752       asymbol **symppend;
2753 
2754       /* Get the canonical symbols.  The generic linker will always
2755 	 have retrieved them by this point, but we are being called by
2756 	 a specific linker, presumably because we are linking
2757 	 different types of object files together.  */
2758       if (! generic_link_read_symbols (input_bfd))
2759 	return FALSE;
2760 
2761       /* Since we have been called by a specific linker, rather than
2762 	 the generic linker, the values of the symbols will not be
2763 	 right.  They will be the values as seen in the input file,
2764 	 not the values of the final link.  We need to fix them up
2765 	 before we can relocate the section.  */
2766       sympp = _bfd_generic_link_get_symbols (input_bfd);
2767       symppend = sympp + _bfd_generic_link_get_symcount (input_bfd);
2768       for (; sympp < symppend; sympp++)
2769 	{
2770 	  asymbol *sym;
2771 	  struct bfd_link_hash_entry *h;
2772 
2773 	  sym = *sympp;
2774 
2775 	  if ((sym->flags & (BSF_INDIRECT
2776 			     | BSF_WARNING
2777 			     | BSF_GLOBAL
2778 			     | BSF_CONSTRUCTOR
2779 			     | BSF_WEAK)) != 0
2780 	      || bfd_is_und_section (bfd_get_section (sym))
2781 	      || bfd_is_com_section (bfd_get_section (sym))
2782 	      || bfd_is_ind_section (bfd_get_section (sym)))
2783 	    {
2784 	      /* sym->udata may have been set by
2785 		 generic_link_add_symbol_list.  */
2786 	      if (sym->udata.p != NULL)
2787 		h = sym->udata.p;
2788 	      else if (bfd_is_und_section (bfd_get_section (sym)))
2789 		h = bfd_wrapped_link_hash_lookup (output_bfd, info,
2790 						  bfd_asymbol_name (sym),
2791 						  FALSE, FALSE, TRUE);
2792 	      else
2793 		h = bfd_link_hash_lookup (info->hash,
2794 					  bfd_asymbol_name (sym),
2795 					  FALSE, FALSE, TRUE);
2796 	      if (h != NULL)
2797 		set_symbol_from_hash (sym, h);
2798 	    }
2799 	}
2800     }
2801 
2802   /* Get and relocate the section contents.  */
2803   sec_size = (input_section->rawsize > input_section->size
2804 	      ? input_section->rawsize
2805 	      : input_section->size);
2806   contents = bfd_malloc (sec_size);
2807   if (contents == NULL && sec_size != 0)
2808     goto error_return;
2809   new_contents = (bfd_get_relocated_section_contents
2810 		  (output_bfd, info, link_order, contents, info->relocatable,
2811 		   _bfd_generic_link_get_symbols (input_bfd)));
2812   if (!new_contents)
2813     goto error_return;
2814 
2815   /* Output the section contents.  */
2816   loc = input_section->output_offset * bfd_octets_per_byte (output_bfd);
2817   if (! bfd_set_section_contents (output_bfd, output_section,
2818 				  new_contents, loc, input_section->size))
2819     goto error_return;
2820 
2821   if (contents != NULL)
2822     free (contents);
2823   return TRUE;
2824 
2825  error_return:
2826   if (contents != NULL)
2827     free (contents);
2828   return FALSE;
2829 }
2830 
2831 /* A little routine to count the number of relocs in a link_order
2832    list.  */
2833 
2834 unsigned int
_bfd_count_link_order_relocs(struct bfd_link_order * link_order)2835 _bfd_count_link_order_relocs (struct bfd_link_order *link_order)
2836 {
2837   register unsigned int c;
2838   register struct bfd_link_order *l;
2839 
2840   c = 0;
2841   for (l = link_order; l != NULL; l = l->next)
2842     {
2843       if (l->type == bfd_section_reloc_link_order
2844 	  || l->type == bfd_symbol_reloc_link_order)
2845 	++c;
2846     }
2847 
2848   return c;
2849 }
2850 
2851 /*
2852 FUNCTION
2853 	bfd_link_split_section
2854 
2855 SYNOPSIS
2856         bfd_boolean bfd_link_split_section (bfd *abfd, asection *sec);
2857 
2858 DESCRIPTION
2859 	Return nonzero if @var{sec} should be split during a
2860 	reloceatable or final link.
2861 
2862 .#define bfd_link_split_section(abfd, sec) \
2863 .       BFD_SEND (abfd, _bfd_link_split_section, (abfd, sec))
2864 .
2865 
2866 */
2867 
2868 bfd_boolean
_bfd_generic_link_split_section(bfd * abfd ATTRIBUTE_UNUSED,asection * sec ATTRIBUTE_UNUSED)2869 _bfd_generic_link_split_section (bfd *abfd ATTRIBUTE_UNUSED,
2870 				 asection *sec ATTRIBUTE_UNUSED)
2871 {
2872   return FALSE;
2873 }
2874 
2875 /*
2876 FUNCTION
2877 	bfd_section_already_linked
2878 
2879 SYNOPSIS
2880         void bfd_section_already_linked (bfd *abfd, asection *sec,
2881 					 struct bfd_link_info *info);
2882 
2883 DESCRIPTION
2884 	Check if @var{sec} has been already linked during a reloceatable
2885 	or final link.
2886 
2887 .#define bfd_section_already_linked(abfd, sec, info) \
2888 .       BFD_SEND (abfd, _section_already_linked, (abfd, sec, info))
2889 .
2890 
2891 */
2892 
2893 /* Sections marked with the SEC_LINK_ONCE flag should only be linked
2894    once into the output.  This routine checks each section, and
2895    arrange to discard it if a section of the same name has already
2896    been linked.  This code assumes that all relevant sections have the
2897    SEC_LINK_ONCE flag set; that is, it does not depend solely upon the
2898    section name.  bfd_section_already_linked is called via
2899    bfd_map_over_sections.  */
2900 
2901 /* The hash table.  */
2902 
2903 static struct bfd_hash_table _bfd_section_already_linked_table;
2904 
2905 /* Support routines for the hash table used by section_already_linked,
2906    initialize the table, traverse, lookup, fill in an entry and remove
2907    the table.  */
2908 
2909 void
bfd_section_already_linked_table_traverse(bfd_boolean (* func)(struct bfd_section_already_linked_hash_entry *,void *),void * info)2910 bfd_section_already_linked_table_traverse
2911   (bfd_boolean (*func) (struct bfd_section_already_linked_hash_entry *,
2912 			void *), void *info)
2913 {
2914   bfd_hash_traverse (&_bfd_section_already_linked_table,
2915 		     (bfd_boolean (*) (struct bfd_hash_entry *,
2916 				       void *)) func,
2917 		     info);
2918 }
2919 
2920 struct bfd_section_already_linked_hash_entry *
bfd_section_already_linked_table_lookup(const char * name)2921 bfd_section_already_linked_table_lookup (const char *name)
2922 {
2923   return ((struct bfd_section_already_linked_hash_entry *)
2924 	  bfd_hash_lookup (&_bfd_section_already_linked_table, name,
2925 			   TRUE, FALSE));
2926 }
2927 
2928 void
bfd_section_already_linked_table_insert(struct bfd_section_already_linked_hash_entry * already_linked_list,asection * sec)2929 bfd_section_already_linked_table_insert
2930   (struct bfd_section_already_linked_hash_entry *already_linked_list,
2931    asection *sec)
2932 {
2933   struct bfd_section_already_linked *l;
2934 
2935   /* Allocate the memory from the same obstack as the hash table is
2936      kept in.  */
2937   l = bfd_hash_allocate (&_bfd_section_already_linked_table, sizeof *l);
2938   l->sec = sec;
2939   l->next = already_linked_list->entry;
2940   already_linked_list->entry = l;
2941 }
2942 
2943 static struct bfd_hash_entry *
already_linked_newfunc(struct bfd_hash_entry * entry ATTRIBUTE_UNUSED,struct bfd_hash_table * table,const char * string ATTRIBUTE_UNUSED)2944 already_linked_newfunc (struct bfd_hash_entry *entry ATTRIBUTE_UNUSED,
2945 			struct bfd_hash_table *table,
2946 			const char *string ATTRIBUTE_UNUSED)
2947 {
2948   struct bfd_section_already_linked_hash_entry *ret =
2949     bfd_hash_allocate (table, sizeof *ret);
2950 
2951   ret->entry = NULL;
2952 
2953   return &ret->root;
2954 }
2955 
2956 bfd_boolean
bfd_section_already_linked_table_init(void)2957 bfd_section_already_linked_table_init (void)
2958 {
2959   return bfd_hash_table_init_n (&_bfd_section_already_linked_table,
2960 				already_linked_newfunc,
2961 				sizeof (struct bfd_section_already_linked_hash_entry),
2962 				42);
2963 }
2964 
2965 void
bfd_section_already_linked_table_free(void)2966 bfd_section_already_linked_table_free (void)
2967 {
2968   bfd_hash_table_free (&_bfd_section_already_linked_table);
2969 }
2970 
2971 /* This is used on non-ELF inputs.  */
2972 
2973 void
_bfd_generic_section_already_linked(bfd * abfd,asection * sec,struct bfd_link_info * info ATTRIBUTE_UNUSED)2974 _bfd_generic_section_already_linked (bfd *abfd, asection *sec,
2975 				     struct bfd_link_info *info ATTRIBUTE_UNUSED)
2976 {
2977   flagword flags;
2978   const char *name;
2979   struct bfd_section_already_linked *l;
2980   struct bfd_section_already_linked_hash_entry *already_linked_list;
2981 
2982   flags = sec->flags;
2983   if ((flags & SEC_LINK_ONCE) == 0)
2984     return;
2985 
2986   /* FIXME: When doing a relocatable link, we may have trouble
2987      copying relocations in other sections that refer to local symbols
2988      in the section being discarded.  Those relocations will have to
2989      be converted somehow; as of this writing I'm not sure that any of
2990      the backends handle that correctly.
2991 
2992      It is tempting to instead not discard link once sections when
2993      doing a relocatable link (technically, they should be discarded
2994      whenever we are building constructors).  However, that fails,
2995      because the linker winds up combining all the link once sections
2996      into a single large link once section, which defeats the purpose
2997      of having link once sections in the first place.  */
2998 
2999   name = bfd_get_section_name (abfd, sec);
3000 
3001   already_linked_list = bfd_section_already_linked_table_lookup (name);
3002 
3003   for (l = already_linked_list->entry; l != NULL; l = l->next)
3004     {
3005       bfd_boolean skip = FALSE;
3006       struct coff_comdat_info *s_comdat
3007 	= bfd_coff_get_comdat_section (abfd, sec);
3008       struct coff_comdat_info *l_comdat
3009 	= bfd_coff_get_comdat_section (l->sec->owner, l->sec);
3010 
3011       /* We may have 3 different sections on the list: group section,
3012 	 comdat section and linkonce section. SEC may be a linkonce or
3013 	 comdat section. We always ignore group section. For non-COFF
3014 	 inputs, we also ignore comdat section.
3015 
3016 	 FIXME: Is that safe to match a linkonce section with a comdat
3017 	 section for COFF inputs?  */
3018       if ((l->sec->flags & SEC_GROUP) != 0)
3019 	skip = TRUE;
3020       else if (bfd_get_flavour (abfd) == bfd_target_coff_flavour)
3021 	{
3022 	  if (s_comdat != NULL
3023 	      && l_comdat != NULL
3024 	      && strcmp (s_comdat->name, l_comdat->name) != 0)
3025 	    skip = TRUE;
3026 	}
3027       else if (l_comdat != NULL)
3028 	skip = TRUE;
3029 
3030       if (!skip)
3031 	{
3032 	  /* The section has already been linked.  See if we should
3033              issue a warning.  */
3034 	  switch (flags & SEC_LINK_DUPLICATES)
3035 	    {
3036 	    default:
3037 	      abort ();
3038 
3039 	    case SEC_LINK_DUPLICATES_DISCARD:
3040 	      break;
3041 
3042 	    case SEC_LINK_DUPLICATES_ONE_ONLY:
3043 	      (*_bfd_error_handler)
3044 		(_("%B: warning: ignoring duplicate section `%A'\n"),
3045 		 abfd, sec);
3046 	      break;
3047 
3048 	    case SEC_LINK_DUPLICATES_SAME_CONTENTS:
3049 	      /* FIXME: We should really dig out the contents of both
3050                  sections and memcmp them.  The COFF/PE spec says that
3051                  the Microsoft linker does not implement this
3052                  correctly, so I'm not going to bother doing it
3053                  either.  */
3054 	      /* Fall through.  */
3055 	    case SEC_LINK_DUPLICATES_SAME_SIZE:
3056 	      if (sec->size != l->sec->size)
3057 		(*_bfd_error_handler)
3058 		  (_("%B: warning: duplicate section `%A' has different size\n"),
3059 		   abfd, sec);
3060 	      break;
3061 	    }
3062 
3063 	  /* Set the output_section field so that lang_add_section
3064 	     does not create a lang_input_section structure for this
3065 	     section.  Since there might be a symbol in the section
3066 	     being discarded, we must retain a pointer to the section
3067 	     which we are really going to use.  */
3068 	  sec->output_section = bfd_abs_section_ptr;
3069 	  sec->kept_section = l->sec;
3070 
3071 	  return;
3072 	}
3073     }
3074 
3075   /* This is the first section with this name.  Record it.  */
3076   bfd_section_already_linked_table_insert (already_linked_list, sec);
3077 }
3078 
3079 /* Convert symbols in excluded output sections to use a kept section.  */
3080 
3081 static bfd_boolean
fix_syms(struct bfd_link_hash_entry * h,void * data)3082 fix_syms (struct bfd_link_hash_entry *h, void *data)
3083 {
3084   bfd *obfd = (bfd *) data;
3085 
3086   if (h->type == bfd_link_hash_warning)
3087     h = h->u.i.link;
3088 
3089   if (h->type == bfd_link_hash_defined
3090       || h->type == bfd_link_hash_defweak)
3091     {
3092       asection *s = h->u.def.section;
3093       if (s != NULL
3094 	  && s->output_section != NULL
3095 	  && (s->output_section->flags & SEC_EXCLUDE) != 0
3096 	  && bfd_section_removed_from_list (obfd, s->output_section))
3097 	{
3098 	  asection *op, *op1;
3099 
3100 	  h->u.def.value += s->output_offset + s->output_section->vma;
3101 
3102 	  /* Find preceding kept section.  */
3103 	  for (op1 = s->output_section->prev; op1 != NULL; op1 = op1->prev)
3104 	    if ((op1->flags & SEC_EXCLUDE) == 0
3105 		&& !bfd_section_removed_from_list (obfd, op1))
3106 	      break;
3107 
3108 	  /* Find following kept section.  Start at prev->next because
3109 	     other sections may have been added after S was removed.  */
3110 	  if (s->output_section->prev != NULL)
3111 	    op = s->output_section->prev->next;
3112 	  else
3113 	    op = s->output_section->owner->sections;
3114 	  for (; op != NULL; op = op->next)
3115 	    if ((op->flags & SEC_EXCLUDE) == 0
3116 		&& !bfd_section_removed_from_list (obfd, op))
3117 	      break;
3118 
3119 	  /* Choose better of two sections, based on flags.  The idea
3120 	     is to choose a section that will be in the same segment
3121 	     as S would have been if it was kept.  */
3122 	  if (op1 == NULL)
3123 	    {
3124 	      if (op == NULL)
3125 		op = bfd_abs_section_ptr;
3126 	    }
3127 	  else if (op == NULL)
3128 	    op = op1;
3129 	  else if (((op1->flags ^ op->flags)
3130 		    & (SEC_ALLOC | SEC_THREAD_LOCAL)) != 0)
3131 	    {
3132 	      if (((op->flags ^ s->flags)
3133 		   & (SEC_ALLOC | SEC_THREAD_LOCAL)) != 0)
3134 		op = op1;
3135 	    }
3136 	  else if (((op1->flags ^ op->flags) & SEC_READONLY) != 0)
3137 	    {
3138 	      if (((op->flags ^ s->flags) & SEC_READONLY) != 0)
3139 		op = op1;
3140 	    }
3141 	  else if (((op1->flags ^ op->flags) & SEC_CODE) != 0)
3142 	    {
3143 	      if (((op->flags ^ s->flags) & SEC_CODE) != 0)
3144 		op = op1;
3145 	    }
3146 	  else
3147 	    {
3148 	      /* Flags we care about are the same.  Prefer the following
3149 		 section if that will result in a positive valued sym.  */
3150 	      if (h->u.def.value < op->vma)
3151 		op = op1;
3152 	    }
3153 
3154 	  h->u.def.value -= op->vma;
3155 	  h->u.def.section = op;
3156 	}
3157     }
3158 
3159   return TRUE;
3160 }
3161 
3162 void
_bfd_fix_excluded_sec_syms(bfd * obfd,struct bfd_link_info * info)3163 _bfd_fix_excluded_sec_syms (bfd *obfd, struct bfd_link_info *info)
3164 {
3165   bfd_link_hash_traverse (info->hash, fix_syms, obfd);
3166 }
3167