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da6b2d99 ILT |
1 | /* linker.c -- BFD linker routines |
2 | Copyright 1993 Free Software Foundation, Inc. | |
3 | Written by Steve Chamberlain and Ian Lance Taylor, Cygnus Support | |
4 | ||
5 | This file is part of BFD | |
6 | ||
7 | GLD is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2, or (at your option) | |
10 | any later version. | |
11 | ||
12 | GLD is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with GLD; see the file COPYING. If not, write to | |
19 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
20 | ||
21 | #include "bfd.h" | |
22 | #include "sysdep.h" | |
23 | #include "libbfd.h" | |
24 | #include "bfdlink.h" | |
25 | #include "genlink.h" | |
26 | ||
d4366f97 ILT |
27 | /* |
28 | SECTION | |
29 | Linker Functions | |
30 | ||
31 | @cindex Linker | |
32 | The linker uses three special entry points in the BFD target | |
33 | vector. It is not necessary to write special routines for | |
34 | these entry points when creating a new BFD back end, since | |
35 | generic versions are provided. However, writing them can | |
36 | speed up linking and make it use significantly less runtime | |
37 | memory. | |
38 | ||
39 | The first routine creates a hash table used by the other | |
40 | routines. The second routine adds the symbols from an object | |
41 | file to the hash table. The third routine takes all the | |
42 | object files and links them together to create the output | |
43 | file. These routines are designed so that the linker proper | |
44 | does not need to know anything about the symbols in the object | |
45 | files that it is linking. The linker merely arranges the | |
46 | sections as directed by the linker script and lets BFD handle | |
47 | the details of symbols and relocs. | |
48 | ||
49 | The second routine and third routines are passed a pointer to | |
50 | a <<struct bfd_link_info>> structure (defined in | |
51 | <<bfdlink.h>>) which holds information relevant to the link, | |
52 | including the linker hash table (which was created by the | |
53 | first routine) and a set of callback functions to the linker | |
54 | proper. | |
55 | ||
56 | The generic linker routines are in <<linker.c>>, and use the | |
57 | header file <<genlink.h>>. As of this writing, the only back | |
58 | ends which have implemented versions of these routines are | |
59 | a.out (in <<aoutx.h>>) and ECOFF (in <<ecoff.c>>). The a.out | |
60 | routines are used as examples throughout this section. | |
61 | ||
62 | @menu | |
63 | @* Creating a Linker Hash Table:: | |
64 | @* Adding Symbols to the Hash Table:: | |
65 | @* Performing the Final Link:: | |
66 | @end menu | |
67 | ||
68 | INODE | |
69 | Creating a Linker Hash Table, Adding Symbols to the Hash Table, Linker Functions, Linker Functions | |
70 | SUBSECTION | |
71 | Creating a linker hash table | |
72 | ||
73 | @cindex _bfd_link_hash_table_create in target vector | |
74 | @cindex target vector (_bfd_link_hash_table_create) | |
75 | The linker routines must create a hash table, which must be | |
76 | derived from <<struct bfd_link_hash_table>> described in | |
77 | <<bfdlink.c>>. @xref{Hash Tables} for information on how to | |
78 | create a derived hash table. This entry point is called using | |
79 | the target vector of the linker output file. | |
80 | ||
81 | The <<_bfd_link_hash_table_create>> entry point must allocate | |
82 | and initialize an instance of the desired hash table. If the | |
83 | back end does not require any additional information to be | |
84 | stored with the entries in the hash table, the entry point may | |
85 | simply create a <<struct bfd_link_hash_table>>. Most likely, | |
86 | however, some additional information will be needed. | |
87 | ||
88 | For example, with each entry in the hash table the a.out | |
89 | linker keeps the index the symbol has in the final output file | |
90 | (this index number is used so that when doing a relocateable | |
91 | link the symbol index used in the output file can be quickly | |
92 | filled in when copying over a reloc). The a.out linker code | |
93 | defines the required structures and functions for a hash table | |
94 | derived from <<struct bfd_link_hash_table>>. The a.out linker | |
95 | hash table is created by the function | |
96 | <<NAME(aout,link_hash_table_create)>>; it simply allocates | |
97 | space for the hash table, initializes it, and returns a | |
98 | pointer to it. | |
99 | ||
100 | When writing the linker routines for a new back end, you will | |
101 | generally not know exactly which fields will be required until | |
102 | you have finished. You should simply create a new hash table | |
103 | which defines no additional fields, and then simply add fields | |
104 | as they become necessary. | |
105 | ||
106 | INODE | |
107 | Adding Symbols to the Hash Table, Performing the Final Link, Creating a Linker Hash Table, Linker Functions | |
108 | SUBSECTION | |
109 | Adding symbols to the hash table | |
110 | ||
111 | @cindex _bfd_link_add_symbols in target vector | |
112 | @cindex target vector (_bfd_link_add_symbols) | |
113 | The linker proper will call the <<_bfd_link_add_symbols>> | |
114 | entry point for each object file or archive which is to be | |
115 | linked (typically these are the files named on the command | |
116 | line, but some may also come from the linker script). The | |
117 | entry point is responsible for examining the file. For an | |
118 | object file, BFD must add any relevant symbol information to | |
119 | the hash table. For an archive, BFD must determine which | |
120 | elements of the archive should be used and adding them to the | |
121 | link. | |
122 | ||
123 | The a.out version of this entry point is | |
124 | <<NAME(aout,link_add_symbols)>>. | |
125 | ||
126 | @menu | |
127 | @* Differing file formats:: | |
128 | @* Adding symbols from an object file:: | |
129 | @* Adding symbols from an archive:: | |
130 | @end menu | |
131 | ||
132 | INODE | |
133 | Differing file formats, Adding symbols from an object file, Adding Symbols to the Hash Table, Adding Symbols to the Hash Table | |
134 | SUBSUBSECTION | |
135 | Differing file formats | |
136 | ||
137 | Normally all the files involved in a link will be of the same | |
138 | format, but it is also possible to link together different | |
139 | format object files, and the back end must support that. The | |
140 | <<_bfd_link_add_symbols>> entry point is called via the target | |
141 | vector of the file to be added. This has an important | |
142 | consequence: the function may not assume that the hash table | |
143 | is the type created by the corresponding | |
144 | <<_bfd_link_hash_table_create>> vector. All the | |
145 | <<_bfd_link_add_symbols>> function can assume about the hash | |
146 | table is that it is derived from <<struct | |
147 | bfd_link_hash_table>>. | |
148 | ||
149 | Sometimes the <<_bfd_link_add_symbols>> function must store | |
150 | some information in the hash table entry to be used by the | |
151 | <<_bfd_final_link>> function. In such a case the <<creator>> | |
152 | field of the hash table must be checked to make sure that the | |
153 | hash table was created by an object file of the same format. | |
154 | ||
155 | The <<_bfd_final_link>> routine must be prepared to handle a | |
156 | hash entry without any extra information added by the | |
157 | <<_bfd_link_add_symbols>> function. A hash entry without | |
158 | extra information will also occur when the linker script | |
159 | directs the linker to create a symbol. Note that, regardless | |
160 | of how a hash table entry is added, all the fields will be | |
161 | initialized to some sort of null value by the hash table entry | |
162 | initialization function. | |
163 | ||
164 | See <<ecoff_link_add_externals>> for an example of how to | |
165 | check the <<creator>> field before saving information (in this | |
166 | case, the ECOFF external symbol debugging information) in a | |
167 | hash table entry. | |
168 | ||
169 | INODE | |
170 | Adding symbols from an object file, Adding symbols from an archive, Differing file formats, Adding Symbols to the Hash Table | |
171 | SUBSUBSECTION | |
172 | Adding symbols from an object file | |
173 | ||
174 | When the <<_bfd_link_add_symbols>> routine is passed an object | |
175 | file, it must add all externally visible symbols in that | |
176 | object file to the hash table. The actual work of adding the | |
177 | symbol to the hash table is normally handled by the function | |
178 | <<_bfd_generic_link_add_one_symbol>>. The | |
179 | <<_bfd_link_add_symbols>> routine is responsible for reading | |
180 | all the symbols from the object file and passing the correct | |
181 | information to <<_bfd_generic_link_add_one_symbol>>. | |
182 | ||
183 | The <<_bfd_link_add_symbols>> routine should not use | |
184 | <<bfd_canonicalize_symtab>> to read the symbols. The point of | |
185 | providing this routine is to avoid the overhead of converting | |
186 | the symbols into generic <<asymbol>> structures. | |
187 | ||
188 | @findex _bfd_generic_link_add_one_symbol | |
189 | <<_bfd_generic_link_add_one_symbol>> handles the details of | |
190 | combining common symbols, warning about multiple definitions, | |
191 | and so forth. It takes arguments which describe the symbol to | |
192 | add, notably symbol flags, a section, and an offset. The | |
193 | symbol flags include such things as <<BSF_WEAK>> or | |
194 | <<BSF_INDIRECT>>. The section is a section in the object | |
195 | file, or something like <<bfd_und_section>> for an undefined | |
196 | symbol or <<bfd_com_section>> for a common symbol. | |
197 | ||
198 | If the <<_bfd_final_link>> routine is also going to need to | |
199 | read the symbol information, the <<_bfd_link_add_symbols>> | |
200 | routine should save it somewhere attached to the object file | |
201 | BFD. However, the information should only be saved if the | |
202 | <<keep_memory>> field of the <<info>> argument is true, so | |
203 | that the <<-no-keep-memory>> linker switch is effective. | |
204 | ||
205 | The a.out function which adds symbols from an object file is | |
206 | <<aout_link_add_object_symbols>>, and most of the interesting | |
207 | work is in <<aout_link_add_symbols>>. The latter saves | |
208 | pointers to the hash tables entries created by | |
209 | <<_bfd_generic_link_add_one_symbol>> indexed by symbol number, | |
210 | so that the <<_bfd_final_link>> routine does not have to call | |
211 | the hash table lookup routine to locate the entry. | |
212 | ||
213 | INODE | |
214 | Adding symbols from an archive, , Adding symbols from an object file, Adding Symbols to the Hash Table | |
215 | SUBSUBSECTION | |
216 | Adding symbols from an archive | |
217 | ||
218 | When the <<_bfd_link_add_symbols>> routine is passed an | |
219 | archive, it must look through the symbols defined by the | |
220 | archive and decide which elements of the archive should be | |
221 | included in the link. For each such element it must call the | |
222 | <<add_archive_element>> linker callback, and it must add the | |
223 | symbols from the object file to the linker hash table. | |
224 | ||
225 | @findex _bfd_generic_link_add_archive_symbols | |
226 | In most cases the work of looking through the symbols in the | |
227 | archive should be done by the | |
228 | <<_bfd_generic_link_add_archive_symbols>> function. This | |
229 | function builds a hash table from the archive symbol table and | |
230 | looks through the list of undefined symbols to see which | |
231 | elements should be included. | |
232 | <<_bfd_generic_link_add_archive_symbols>> is passed a function | |
233 | to call to make the final decision about adding an archive | |
234 | element to the link and to do the actual work of adding the | |
235 | symbols to the linker hash table. | |
236 | ||
237 | The function passed to | |
238 | <<_bfd_generic_link_add_archive_symbols>> must read the | |
239 | symbols of the archive element and decide whether the archive | |
240 | element should be included in the link. If the element is to | |
241 | be included, the <<add_archive_element>> linker callback | |
242 | routine must be called with the element as an argument, and | |
243 | the elements symbols must be added to the linker hash table | |
244 | just as though the element had itself been passed to the | |
245 | <<_bfd_link_add_symbols>> function. | |
246 | ||
247 | When the a.out <<_bfd_link_add_symbols>> function receives an | |
248 | archive, it calls <<_bfd_generic_link_add_archive_symbols>> | |
249 | passing <<aout_link_check_archive_element>> as the function | |
250 | argument. <<aout_link_check_archive_element>> calls | |
251 | <<aout_link_check_ar_symbols>>. If the latter decides to add | |
252 | the element (an element is only added if it provides a real, | |
253 | non-common, definition for a previously undefined or common | |
254 | symbol) it calls the <<add_archive_element>> callback and then | |
255 | <<aout_link_check_archive_element>> calls | |
256 | <<aout_link_add_symbols>> to actually add the symbols to the | |
257 | linker hash table. | |
258 | ||
259 | The ECOFF back end is unusual in that it does not normally | |
260 | call <<_bfd_generic_link_add_archive_symbols>>, because ECOFF | |
261 | archives already contain a hash table of symbols. The ECOFF | |
262 | back end searches the archive itself to avoid the overhead of | |
263 | creating a new hash table. | |
264 | ||
265 | INODE | |
266 | Performing the Final Link, , Adding Symbols to the Hash Table, Linker Functions | |
267 | SUBSECTION | |
268 | Performing the final link | |
269 | ||
270 | @cindex _bfd_link_final_link in target vector | |
271 | @cindex target vector (_bfd_final_link) | |
272 | When all the input files have been processed, the linker calls | |
273 | the <<_bfd_final_link>> entry point of the output BFD. This | |
274 | routine is responsible for producing the final output file, | |
275 | which has several aspects. It must relocate the contents of | |
276 | the input sections and copy the data into the output sections. | |
277 | It must build an output symbol table including any local | |
278 | symbols from the input files and the global symbols from the | |
279 | hash table. When producing relocateable output, it must | |
280 | modify the input relocs and write them into the output file. | |
281 | There may also be object format dependent work to be done. | |
282 | ||
283 | The linker will also call the <<write_object_contents>> entry | |
284 | point when the BFD is closed. The two entry points must work | |
285 | together in order to produce the correct output file. | |
286 | ||
287 | The details of how this works are inevitably dependent upon | |
288 | the specific object file format. The a.out | |
289 | <<_bfd_final_link>> routine is <<NAME(aout,final_link)>>. | |
290 | ||
291 | @menu | |
292 | @* Information provided by the linker:: | |
293 | @* Relocating the section contents:: | |
294 | @* Writing the symbol table:: | |
295 | @end menu | |
296 | ||
297 | INODE | |
298 | Information provided by the linker, Relocating the section contents, Performing the Final Link, Performing the Final Link | |
299 | SUBSUBSECTION | |
300 | Information provided by the linker | |
301 | ||
302 | Before the linker calls the <<_bfd_final_link>> entry point, | |
303 | it sets up some data structures for the function to use. | |
304 | ||
305 | The <<input_bfds>> field of the <<bfd_link_info>> structure | |
306 | will point to a list of all the input files included in the | |
307 | link. These files are linked through the <<link_next>> field | |
308 | of the <<bfd>> structure. | |
309 | ||
310 | Each section in the output file will have a list of | |
311 | <<link_order>> structures attached to the <<link_order_head>> | |
312 | field (the <<link_order>> structure is defined in | |
313 | <<bfdlink.h>>). These structures describe how to create the | |
314 | contents of the output section in terms of the contents of | |
315 | various input sections, fill constants, and, eventually, other | |
316 | types of information. | |
317 | ||
318 | INODE | |
319 | Relocating the section contents, Writing the symbol table, Information provided by the linker, Performing the Final Link | |
320 | SUBSUBSECTION | |
321 | Relocating the section contents | |
322 | ||
323 | The <<_bfd_final_link>> function should look through the | |
324 | <<link_order>> structures attached to each section of the | |
325 | output file. Each <<link_order>> structure should either be | |
326 | handled specially, or it should be passed to the function | |
327 | <<_bfd_default_link_order>> which will do the right thing | |
328 | (<<_bfd_default_link_order>> is defined in <<linker.c>>). | |
329 | ||
330 | For efficiency, a <<link_order>> of type | |
331 | <<bfd_indirect_link_order>> whose associated section belongs | |
332 | to a BFD of the same format as the output BFD must be handled | |
333 | specially. This type of <<link_order>> describes part of an | |
334 | output section in terms of a section belonging to one of the | |
335 | input files. The <<_bfd_final_link>> function should read the | |
336 | contents of the section and any associated relocs, apply the | |
337 | relocs to the section contents, and write out the modified | |
338 | section contents. If performing a relocateable link, the | |
339 | relocs themselves must also be modified and written out. | |
340 | ||
341 | @findex _bfd_relocate_contents | |
342 | @findex _bfd_final_link_relocate | |
343 | The functions <<_bfd_relocate_contents>> and | |
344 | <<_bfd_final_link_relocate>> provide some general support for | |
345 | performing the actual relocations, notably overflow checking. | |
346 | Their arguments include information about the symbol the | |
347 | relocation is against and a <<reloc_howto_type>> argument | |
348 | which describes the relocation to perform. These functions | |
349 | are defined in <<reloc.c>>. | |
350 | ||
351 | The a.out function which handles reading, relocating, and | |
352 | writing section contents is <<aout_link_input_section>>. The | |
353 | actual relocation is done in <<aout_link_input_section_std>> | |
354 | and <<aout_link_input_section_ext>>. | |
355 | ||
356 | INODE | |
357 | Writing the symbol table, , Relocating the section contents, Performing the Final Link | |
358 | SUBSUBSECTION | |
359 | Writing the symbol table | |
360 | ||
361 | The <<_bfd_final_link>> function must gather all the symbols | |
362 | in the input files and write them out. It must also write out | |
363 | all the symbols in the global hash table. This must be | |
364 | controlled by the <<strip>> and <<discard>> fields of the | |
365 | <<bfd_link_info>> structure. | |
366 | ||
367 | The local symbols of the input files will not have been | |
368 | entered into the linker hash table. The <<_bfd_final_link>> | |
369 | routine must consider each input file and include the symbols | |
370 | in the output file. It may be convenient to do this when | |
371 | looking through the <<link_order>> structures, or it may be | |
372 | done by stepping through the <<input_bfds>> list. | |
373 | ||
374 | The <<_bfd_final_link>> routine must also traverse the global | |
375 | hash table to gather all the externally visible symbols. It | |
376 | is possible that most of the externally visible symbols may be | |
377 | written out when considering the symbols of each input file, | |
378 | but it is still necessary to traverse the hash table since the | |
379 | linker script may have defined some symbols that are not in | |
380 | any of the input files. The <<written>> field in the | |
381 | <<bfd_link_hash_entry>> structure may be used to determine | |
382 | which entries in the hash table have not already been written | |
383 | out. | |
384 | ||
385 | The <<strip>> field of the <<bfd_link_info>> structure | |
386 | controls which symbols are written out. The possible values | |
387 | are listed in <<bfdlink.h>>. If the value is <<strip_some>>, | |
388 | then the <<keep_hash>> field of the <<bfd_link_info>> | |
389 | structure is a hash table of symbols to keep; each symbol | |
390 | should be looked up in this hash table, and only symbols which | |
391 | are present should be included in the output file. | |
392 | ||
393 | If the <<strip>> field of the <<bfd_link_info>> structure | |
394 | permits local symbols to be written out, the <<discard>> field | |
395 | is used to further controls which local symbols are included | |
396 | in the output file. If the value is <<discard_l>>, then all | |
397 | local symbols which begin with a certain prefix are discarded; | |
398 | this prefix is described by the <<lprefix>> and | |
399 | <<lprefix_len>> fields of the <<bfd_link_info>> structure. | |
400 | ||
401 | The a.out backend handles symbols by calling | |
402 | <<aout_link_write_symbols>> on each input BFD and then | |
403 | traversing the global hash table with the function | |
404 | <<aout_link_write_other_symbol>>. It builds a string table | |
405 | while writing out the symbols, which is written to the output | |
406 | file at the end of <<NAME(aout,final_link)>>. | |
407 | */ | |
408 | ||
da6b2d99 ILT |
409 | static struct bfd_hash_entry *generic_link_hash_newfunc |
410 | PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, | |
411 | const char *)); | |
412 | static boolean generic_link_add_object_symbols | |
413 | PARAMS ((bfd *, struct bfd_link_info *)); | |
414 | static boolean generic_link_check_archive_element | |
415 | PARAMS ((bfd *, struct bfd_link_info *, boolean *pneeded)); | |
416 | static boolean generic_link_add_symbol_list | |
417 | PARAMS ((bfd *, struct bfd_link_info *, bfd_size_type count, asymbol **)); | |
418 | static boolean generic_add_output_symbol | |
419 | PARAMS ((bfd *, size_t *psymalloc, asymbol *)); | |
420 | static boolean default_fill_link_order | |
421 | PARAMS ((bfd *, struct bfd_link_info *, asection *, | |
422 | struct bfd_link_order *)); | |
6e07e54f ILT |
423 | static boolean default_indirect_link_order |
424 | PARAMS ((bfd *, struct bfd_link_info *, asection *, | |
425 | struct bfd_link_order *)); | |
da6b2d99 ILT |
426 | |
427 | /* The link hash table structure is defined in bfdlink.h. It provides | |
428 | a base hash table which the backend specific hash tables are built | |
429 | upon. */ | |
430 | ||
431 | /* Routine to create an entry in the link hash table. */ | |
432 | ||
433 | struct bfd_hash_entry * | |
434 | _bfd_link_hash_newfunc (entry, table, string) | |
435 | struct bfd_hash_entry *entry; | |
436 | struct bfd_hash_table *table; | |
437 | const char *string; | |
438 | { | |
439 | struct bfd_link_hash_entry *ret = (struct bfd_link_hash_entry *) entry; | |
440 | ||
441 | /* Allocate the structure if it has not already been allocated by a | |
442 | subclass. */ | |
443 | if (ret == (struct bfd_link_hash_entry *) NULL) | |
444 | ret = ((struct bfd_link_hash_entry *) | |
445 | bfd_hash_allocate (table, sizeof (struct bfd_link_hash_entry))); | |
446 | ||
447 | /* Call the allocation method of the superclass. */ | |
448 | ret = ((struct bfd_link_hash_entry *) | |
449 | bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string)); | |
450 | ||
451 | /* Initialize the local fields. */ | |
452 | ret->type = bfd_link_hash_new; | |
453 | ret->written = false; | |
454 | ret->next = NULL; | |
455 | ||
456 | return (struct bfd_hash_entry *) ret; | |
457 | } | |
458 | ||
459 | /* Initialize a link hash table. The BFD argument is the one | |
460 | responsible for creating this table. */ | |
461 | ||
462 | boolean | |
463 | _bfd_link_hash_table_init (table, abfd, newfunc) | |
464 | struct bfd_link_hash_table *table; | |
465 | bfd *abfd; | |
466 | struct bfd_hash_entry *(*newfunc) PARAMS ((struct bfd_hash_entry *, | |
467 | struct bfd_hash_table *, | |
468 | const char *)); | |
469 | { | |
470 | table->creator = abfd->xvec; | |
471 | table->undefs = NULL; | |
472 | table->undefs_tail = NULL; | |
473 | return bfd_hash_table_init (&table->table, newfunc); | |
474 | } | |
475 | ||
476 | /* Look up a symbol in a link hash table. If follow is true, we | |
477 | follow bfd_link_hash_indirect and bfd_link_hash_warning links to | |
478 | the real symbol. */ | |
479 | ||
480 | struct bfd_link_hash_entry * | |
481 | bfd_link_hash_lookup (table, string, create, copy, follow) | |
482 | struct bfd_link_hash_table *table; | |
483 | const char *string; | |
484 | boolean create; | |
485 | boolean copy; | |
486 | boolean follow; | |
487 | { | |
488 | struct bfd_link_hash_entry *ret; | |
489 | ||
490 | ret = ((struct bfd_link_hash_entry *) | |
491 | bfd_hash_lookup (&table->table, string, create, copy)); | |
492 | ||
493 | if (follow && ret != (struct bfd_link_hash_entry *) NULL) | |
494 | { | |
495 | while (ret->type == bfd_link_hash_indirect | |
496 | || ret->type == bfd_link_hash_warning) | |
497 | ret = ret->u.i.link; | |
498 | } | |
499 | ||
500 | return ret; | |
501 | } | |
502 | ||
503 | /* Traverse a generic link hash table. The only reason this is not a | |
504 | macro is to do better type checking. This code presumes that an | |
d4366f97 | 505 | argument passed as a struct bfd_hash_entry * may be caught as a |
da6b2d99 ILT |
506 | struct bfd_link_hash_entry * with no explicit cast required on the |
507 | call. */ | |
508 | ||
509 | void | |
510 | bfd_link_hash_traverse (table, func, info) | |
511 | struct bfd_link_hash_table *table; | |
512 | boolean (*func) PARAMS ((struct bfd_link_hash_entry *, PTR)); | |
513 | PTR info; | |
514 | { | |
515 | bfd_hash_traverse (&table->table, | |
516 | ((boolean (*) PARAMS ((struct bfd_hash_entry *, PTR))) | |
517 | func), | |
518 | info); | |
519 | } | |
520 | ||
521 | /* Add a symbol to the linker hash table undefs list. */ | |
522 | ||
523 | INLINE void | |
524 | bfd_link_add_undef (table, h) | |
525 | struct bfd_link_hash_table *table; | |
526 | struct bfd_link_hash_entry *h; | |
527 | { | |
528 | BFD_ASSERT (h->next == NULL); | |
529 | if (table->undefs_tail != (struct bfd_link_hash_entry *) NULL) | |
530 | table->undefs_tail->next = h; | |
531 | if (table->undefs == (struct bfd_link_hash_entry *) NULL) | |
532 | table->undefs = h; | |
533 | table->undefs_tail = h; | |
534 | } | |
535 | \f | |
536 | /* Routine to create an entry in an generic link hash table. */ | |
537 | ||
538 | static struct bfd_hash_entry * | |
539 | generic_link_hash_newfunc (entry, table, string) | |
540 | struct bfd_hash_entry *entry; | |
541 | struct bfd_hash_table *table; | |
542 | const char *string; | |
543 | { | |
544 | struct generic_link_hash_entry *ret = | |
545 | (struct generic_link_hash_entry *) entry; | |
546 | ||
547 | /* Allocate the structure if it has not already been allocated by a | |
548 | subclass. */ | |
549 | if (ret == (struct generic_link_hash_entry *) NULL) | |
550 | ret = ((struct generic_link_hash_entry *) | |
551 | bfd_hash_allocate (table, sizeof (struct generic_link_hash_entry))); | |
552 | ||
553 | /* Call the allocation method of the superclass. */ | |
554 | ret = ((struct generic_link_hash_entry *) | |
555 | _bfd_link_hash_newfunc ((struct bfd_hash_entry *) ret, | |
556 | table, string)); | |
557 | ||
558 | /* Set local fields. */ | |
559 | ret->sym = NULL; | |
560 | ||
561 | return (struct bfd_hash_entry *) ret; | |
562 | } | |
563 | ||
564 | /* Create an generic link hash table. */ | |
565 | ||
566 | struct bfd_link_hash_table * | |
567 | _bfd_generic_link_hash_table_create (abfd) | |
568 | bfd *abfd; | |
569 | { | |
570 | struct generic_link_hash_table *ret; | |
571 | ||
572 | ret = ((struct generic_link_hash_table *) | |
573 | bfd_xmalloc (sizeof (struct generic_link_hash_table))); | |
574 | if (! _bfd_link_hash_table_init (&ret->root, abfd, | |
575 | generic_link_hash_newfunc)) | |
576 | { | |
577 | free (ret); | |
578 | return (struct bfd_link_hash_table *) NULL; | |
579 | } | |
580 | return &ret->root; | |
581 | } | |
582 | \f | |
583 | /* Generic function to add symbols from an object file to the global | |
584 | hash table. */ | |
585 | ||
586 | boolean | |
587 | _bfd_generic_link_add_symbols (abfd, info) | |
588 | bfd *abfd; | |
589 | struct bfd_link_info *info; | |
590 | { | |
591 | boolean ret; | |
592 | ||
593 | switch (bfd_get_format (abfd)) | |
594 | { | |
595 | case bfd_object: | |
596 | ret = generic_link_add_object_symbols (abfd, info); | |
597 | break; | |
598 | case bfd_archive: | |
599 | ret = _bfd_generic_link_add_archive_symbols | |
600 | (abfd, info, generic_link_check_archive_element); | |
601 | break; | |
602 | default: | |
603 | bfd_error = wrong_format; | |
604 | ret = false; | |
605 | } | |
606 | ||
607 | /* If we might be using the C based alloca function, make sure we | |
608 | have dumped the symbol tables we just allocated. */ | |
609 | #ifndef __GNUC__ | |
610 | #ifndef alloca | |
611 | alloca (0); | |
612 | #endif | |
613 | #endif | |
614 | ||
615 | return ret; | |
616 | } | |
617 | ||
618 | /* Add symbols from an object file to the global hash table. */ | |
619 | ||
620 | static boolean | |
621 | generic_link_add_object_symbols (abfd, info) | |
622 | bfd *abfd; | |
623 | struct bfd_link_info *info; | |
624 | { | |
625 | size_t symsize; | |
626 | asymbol **symbols; | |
627 | bfd_size_type symbol_count; | |
628 | ||
629 | symsize = get_symtab_upper_bound (abfd); | |
630 | symbols = (asymbol **) alloca (symsize); | |
631 | symbol_count = bfd_canonicalize_symtab (abfd, symbols); | |
632 | ||
633 | return generic_link_add_symbol_list (abfd, info, symbol_count, symbols); | |
634 | } | |
635 | \f | |
636 | /* We build a hash table of all symbols defined in an archive. */ | |
637 | ||
638 | /* An archive symbol may be defined by multiple archive elements. | |
639 | This linked list is used to hold the elements. */ | |
640 | ||
641 | struct archive_list | |
642 | { | |
643 | struct archive_list *next; | |
644 | int indx; | |
645 | }; | |
646 | ||
647 | /* An entry in an archive hash table. */ | |
648 | ||
649 | struct archive_hash_entry | |
650 | { | |
651 | struct bfd_hash_entry root; | |
652 | /* Where the symbol is defined. */ | |
653 | struct archive_list *defs; | |
654 | }; | |
655 | ||
656 | /* An archive hash table itself. */ | |
657 | ||
658 | struct archive_hash_table | |
659 | { | |
660 | struct bfd_hash_table table; | |
661 | }; | |
662 | ||
663 | static struct bfd_hash_entry *archive_hash_newfunc | |
664 | PARAMS ((struct bfd_hash_entry *, struct bfd_hash_table *, const char *)); | |
665 | static boolean archive_hash_table_init | |
666 | PARAMS ((struct archive_hash_table *, | |
667 | struct bfd_hash_entry *(*) (struct bfd_hash_entry *, | |
668 | struct bfd_hash_table *, | |
669 | const char *))); | |
670 | ||
671 | /* Create a new entry for an archive hash table. */ | |
672 | ||
673 | static struct bfd_hash_entry * | |
674 | archive_hash_newfunc (entry, table, string) | |
675 | struct bfd_hash_entry *entry; | |
676 | struct bfd_hash_table *table; | |
677 | const char *string; | |
678 | { | |
679 | struct archive_hash_entry *ret = (struct archive_hash_entry *) entry; | |
680 | ||
681 | /* Allocate the structure if it has not already been allocated by a | |
682 | subclass. */ | |
683 | if (ret == (struct archive_hash_entry *) NULL) | |
684 | ret = ((struct archive_hash_entry *) | |
685 | bfd_hash_allocate (table, sizeof (struct archive_hash_entry))); | |
686 | ||
687 | /* Call the allocation method of the superclass. */ | |
688 | ret = ((struct archive_hash_entry *) | |
689 | bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string)); | |
690 | ||
691 | /* Initialize the local fields. */ | |
692 | ret->defs = (struct archive_list *) NULL; | |
693 | ||
694 | return (struct bfd_hash_entry *) ret; | |
695 | } | |
696 | ||
697 | /* Initialize an archive hash table. */ | |
698 | ||
699 | static boolean | |
700 | archive_hash_table_init (table, newfunc) | |
701 | struct archive_hash_table *table; | |
702 | struct bfd_hash_entry *(*newfunc) PARAMS ((struct bfd_hash_entry *, | |
703 | struct bfd_hash_table *, | |
704 | const char *)); | |
705 | { | |
706 | return bfd_hash_table_init (&table->table, newfunc); | |
707 | } | |
708 | ||
709 | /* Look up an entry in an archive hash table. */ | |
710 | ||
711 | #define archive_hash_lookup(t, string, create, copy) \ | |
712 | ((struct archive_hash_entry *) \ | |
713 | bfd_hash_lookup (&(t)->table, (string), (create), (copy))) | |
714 | ||
715 | /* Free an archive hash table. */ | |
716 | ||
717 | #define archive_hash_table_free(t) bfd_hash_table_free (&(t)->table) | |
718 | ||
719 | /* Generic function to add symbols from an archive file to the global | |
720 | hash file. This function presumes that the archive symbol table | |
721 | has already been read in (this is normally done by the | |
722 | bfd_check_format entry point). It looks through the undefined and | |
723 | common symbols and searches the archive symbol table for them. If | |
724 | it finds an entry, it includes the associated object file in the | |
725 | link. | |
726 | ||
727 | The old linker looked through the archive symbol table for | |
728 | undefined symbols. We do it the other way around, looking through | |
729 | undefined symbols for symbols defined in the archive. The | |
730 | advantage of the newer scheme is that we only have to look through | |
731 | the list of undefined symbols once, whereas the old method had to | |
732 | re-search the symbol table each time a new object file was added. | |
733 | ||
734 | The CHECKFN argument is used to see if an object file should be | |
735 | included. CHECKFN should set *PNEEDED to true if the object file | |
736 | should be included, and must also call the bfd_link_info | |
737 | add_archive_element callback function and handle adding the symbols | |
738 | to the global hash table. CHECKFN should only return false if some | |
739 | sort of error occurs. | |
740 | ||
741 | For some formats, such as a.out, it is possible to look through an | |
742 | object file but not actually include it in the link. The | |
743 | archive_pass field in a BFD is used to avoid checking the symbols | |
744 | of an object files too many times. When an object is included in | |
745 | the link, archive_pass is set to -1. If an object is scanned but | |
746 | not included, archive_pass is set to the pass number. The pass | |
747 | number is incremented each time a new object file is included. The | |
748 | pass number is used because when a new object file is included it | |
749 | may create new undefined symbols which cause a previously examined | |
750 | object file to be included. */ | |
751 | ||
752 | boolean | |
753 | _bfd_generic_link_add_archive_symbols (abfd, info, checkfn) | |
754 | bfd *abfd; | |
755 | struct bfd_link_info *info; | |
756 | boolean (*checkfn) PARAMS ((bfd *, struct bfd_link_info *, | |
757 | boolean *pneeded)); | |
758 | { | |
759 | carsym *arsyms; | |
760 | carsym *arsym_end; | |
761 | register carsym *arsym; | |
762 | int pass; | |
763 | struct archive_hash_table arsym_hash; | |
764 | int indx; | |
765 | struct bfd_link_hash_entry **pundef; | |
766 | ||
767 | if (! bfd_has_map (abfd)) | |
768 | { | |
769 | bfd_error = no_symbols; | |
770 | return false; | |
771 | } | |
772 | ||
773 | arsyms = bfd_ardata (abfd)->symdefs; | |
774 | arsym_end = arsyms + bfd_ardata (abfd)->symdef_count; | |
775 | ||
776 | /* In order to quickly determine whether an symbol is defined in | |
777 | this archive, we build a hash table of the symbols. */ | |
778 | if (! archive_hash_table_init (&arsym_hash, archive_hash_newfunc)) | |
779 | return false; | |
780 | for (arsym = arsyms, indx = 0; arsym < arsym_end; arsym++, indx++) | |
781 | { | |
782 | struct archive_hash_entry *arh; | |
783 | struct archive_list *l; | |
784 | ||
785 | arh = archive_hash_lookup (&arsym_hash, arsym->name, true, false); | |
786 | if (arh == (struct archive_hash_entry *) NULL) | |
787 | return false; | |
788 | l = (struct archive_list *) alloca (sizeof (struct archive_list)); | |
789 | l->next = arh->defs; | |
790 | arh->defs = l; | |
791 | l->indx = indx; | |
792 | } | |
793 | ||
794 | pass = 1; | |
795 | ||
796 | /* New undefined symbols are added to the end of the list, so we | |
797 | only need to look through it once. */ | |
798 | pundef = &info->hash->undefs; | |
799 | while (*pundef != (struct bfd_link_hash_entry *) NULL) | |
800 | { | |
801 | struct bfd_link_hash_entry *h; | |
802 | struct archive_hash_entry *arh; | |
803 | struct archive_list *l; | |
804 | ||
805 | h = *pundef; | |
806 | ||
807 | /* When a symbol is defined, it is not necessarily removed from | |
808 | the list. */ | |
809 | if (h->type != bfd_link_hash_undefined | |
810 | && h->type != bfd_link_hash_common) | |
811 | { | |
812 | /* Remove this entry from the list, for general cleanliness | |
813 | and because we are going to look through the list again | |
814 | if we search any more libraries. We can't remove the | |
815 | entry if it is the tail, because that would lose any | |
816 | entries we add to the list later on. */ | |
817 | if (*pundef != info->hash->undefs_tail) | |
818 | *pundef = (*pundef)->next; | |
819 | else | |
820 | pundef = &(*pundef)->next; | |
821 | continue; | |
822 | } | |
823 | ||
824 | /* Look for this symbol in the archive symbol map. */ | |
825 | arh = archive_hash_lookup (&arsym_hash, h->root.string, false, false); | |
826 | if (arh == (struct archive_hash_entry *) NULL) | |
827 | { | |
828 | pundef = &(*pundef)->next; | |
829 | continue; | |
830 | } | |
831 | ||
832 | /* Look at all the objects which define this symbol. */ | |
833 | for (l = arh->defs; l != (struct archive_list *) NULL; l = l->next) | |
834 | { | |
835 | bfd *element; | |
836 | boolean needed; | |
837 | ||
838 | /* If the symbol has gotten defined along the way, quit. */ | |
839 | if (h->type != bfd_link_hash_undefined | |
840 | && h->type != bfd_link_hash_common) | |
841 | break; | |
842 | ||
843 | element = bfd_get_elt_at_index (abfd, l->indx); | |
844 | if (element == (bfd *) NULL) | |
845 | return false; | |
846 | ||
847 | /* If we've already included this element, or if we've | |
848 | already checked it on this pass, continue. */ | |
849 | if (element->archive_pass == -1 | |
850 | || element->archive_pass == pass) | |
851 | continue; | |
852 | ||
853 | /* If we can't figure this element out, just ignore it. */ | |
854 | if (! bfd_check_format (element, bfd_object)) | |
855 | { | |
856 | element->archive_pass = -1; | |
857 | continue; | |
858 | } | |
859 | ||
860 | /* CHECKFN will see if this element should be included, and | |
861 | go ahead and include it if appropriate. */ | |
862 | if (! (*checkfn) (element, info, &needed)) | |
863 | return false; | |
864 | ||
865 | if (! needed) | |
866 | element->archive_pass = pass; | |
867 | else | |
868 | { | |
869 | element->archive_pass = -1; | |
870 | ||
871 | /* Increment the pass count to show that we may need to | |
872 | recheck object files which were already checked. */ | |
873 | ++pass; | |
874 | } | |
875 | } | |
876 | ||
877 | pundef = &(*pundef)->next; | |
878 | } | |
879 | ||
880 | archive_hash_table_free (&arsym_hash); | |
881 | ||
882 | return true; | |
883 | } | |
884 | \f | |
885 | /* See if we should include an archive element. */ | |
886 | ||
887 | static boolean | |
888 | generic_link_check_archive_element (abfd, info, pneeded) | |
889 | bfd *abfd; | |
890 | struct bfd_link_info *info; | |
891 | boolean *pneeded; | |
892 | { | |
893 | size_t symsize; | |
894 | asymbol **symbols; | |
895 | bfd_size_type symbol_count; | |
896 | asymbol **pp, **ppend; | |
897 | ||
898 | *pneeded = false; | |
899 | ||
900 | symsize = get_symtab_upper_bound (abfd); | |
901 | symbols = (asymbol **) alloca (symsize); | |
902 | symbol_count = bfd_canonicalize_symtab (abfd, symbols); | |
903 | ||
904 | pp = symbols; | |
905 | ppend = symbols + symbol_count; | |
906 | for (; pp < ppend; pp++) | |
907 | { | |
908 | asymbol *p; | |
909 | struct bfd_link_hash_entry *h; | |
910 | ||
911 | p = *pp; | |
912 | ||
913 | /* We are only interested in globally visible symbols. */ | |
914 | if (! bfd_is_com_section (p->section) | |
915 | && (p->flags & (BSF_GLOBAL | BSF_INDIRECT | BSF_WEAK)) == 0) | |
916 | continue; | |
917 | ||
918 | /* We are only interested if we know something about this | |
919 | symbol, and it is undefined or common. An undefined weak | |
920 | symbol (type bfd_link_hash_weak) is not considered to be a | |
921 | reference when pulling files out of an archive. See the SVR4 | |
922 | ABI, p. 4-27. */ | |
923 | h = bfd_link_hash_lookup (info->hash, bfd_asymbol_name (p), false, | |
924 | false, true); | |
925 | if (h == (struct bfd_link_hash_entry *) NULL | |
926 | || (h->type != bfd_link_hash_undefined | |
927 | && h->type != bfd_link_hash_common)) | |
928 | continue; | |
929 | ||
930 | /* P is a symbol we are looking for. */ | |
931 | ||
932 | if (! bfd_is_com_section (p->section)) | |
933 | { | |
934 | /* This object file defines this symbol, so pull it in. */ | |
935 | if (! (*info->callbacks->add_archive_element) (info, abfd, | |
936 | bfd_asymbol_name (p))) | |
937 | return false; | |
938 | if (! generic_link_add_symbol_list (abfd, info, symbol_count, | |
939 | symbols)) | |
940 | return false; | |
941 | *pneeded = true; | |
942 | return true; | |
943 | } | |
944 | ||
945 | /* P is a common symbol. */ | |
946 | ||
947 | if (h->type == bfd_link_hash_undefined) | |
948 | { | |
949 | bfd *symbfd; | |
950 | ||
951 | symbfd = h->u.undef.abfd; | |
952 | if (symbfd == (bfd *) NULL) | |
953 | { | |
954 | /* This symbol was created as undefined from outside | |
955 | BFD. We assume that we should link in the object | |
956 | file. This is for the -u option in the linker. */ | |
957 | if (! (*info->callbacks->add_archive_element) | |
958 | (info, abfd, bfd_asymbol_name (p))) | |
959 | return false; | |
960 | *pneeded = true; | |
961 | return true; | |
962 | } | |
963 | ||
964 | /* Turn the symbol into a common symbol but do not link in | |
965 | the object file. This is how a.out works. Object | |
966 | formats that require different semantics must implement | |
967 | this function differently. This symbol is already on the | |
6e07e54f ILT |
968 | undefs list. We add the section to a common section |
969 | attached to symbfd to ensure that it is in a BFD which | |
970 | will be linked in. */ | |
da6b2d99 ILT |
971 | h->type = bfd_link_hash_common; |
972 | h->u.c.size = bfd_asymbol_value (p); | |
6e07e54f ILT |
973 | if (p->section == &bfd_com_section) |
974 | h->u.c.section = bfd_make_section_old_way (symbfd, "COMMON"); | |
975 | else | |
976 | h->u.c.section = bfd_make_section_old_way (symbfd, | |
977 | p->section->name); | |
a20bdb43 | 978 | h->u.c.section->flags = SEC_ALLOC; |
da6b2d99 ILT |
979 | } |
980 | else | |
981 | { | |
982 | /* Adjust the size of the common symbol if necessary. This | |
983 | is how a.out works. Object formats that require | |
984 | different semantics must implement this function | |
985 | differently. */ | |
986 | if (bfd_asymbol_value (p) > h->u.c.size) | |
987 | h->u.c.size = bfd_asymbol_value (p); | |
988 | } | |
989 | } | |
990 | ||
991 | /* This archive element is not needed. */ | |
992 | return true; | |
993 | } | |
994 | ||
995 | /* Add the symbol from an object file to the global hash table. */ | |
996 | ||
997 | static boolean | |
998 | generic_link_add_symbol_list (abfd, info, symbol_count, symbols) | |
999 | bfd *abfd; | |
1000 | struct bfd_link_info *info; | |
1001 | bfd_size_type symbol_count; | |
1002 | asymbol **symbols; | |
1003 | { | |
1004 | asymbol **pp, **ppend; | |
1005 | ||
1006 | pp = symbols; | |
1007 | ppend = symbols + symbol_count; | |
1008 | for (; pp < ppend; pp++) | |
1009 | { | |
1010 | asymbol *p; | |
1011 | ||
1012 | p = *pp; | |
1013 | ||
1014 | if ((p->flags & (BSF_INDIRECT | |
1015 | | BSF_WARNING | |
1016 | | BSF_GLOBAL | |
1017 | | BSF_CONSTRUCTOR | |
1018 | | BSF_WEAK)) != 0 | |
1019 | || bfd_get_section (p) == &bfd_und_section | |
1020 | || bfd_is_com_section (bfd_get_section (p)) | |
1021 | || bfd_get_section (p) == &bfd_ind_section) | |
1022 | { | |
1023 | const char *name; | |
1024 | const char *string; | |
1025 | struct generic_link_hash_entry *h; | |
1026 | ||
1027 | name = bfd_asymbol_name (p); | |
1028 | if ((p->flags & BSF_INDIRECT) != 0 | |
1029 | || p->section == &bfd_ind_section) | |
1030 | string = bfd_asymbol_name ((asymbol *) p->value); | |
1031 | else if ((p->flags & BSF_WARNING) != 0) | |
1032 | { | |
1033 | /* The name of P is actually the warning string, and the | |
1034 | value is actually a pointer to the symbol to warn | |
1035 | about. */ | |
1036 | string = name; | |
1037 | name = bfd_asymbol_name ((asymbol *) p->value); | |
1038 | } | |
1039 | else | |
1040 | string = NULL; | |
6e07e54f ILT |
1041 | |
1042 | /* We pass the constructor argument as false, for | |
1043 | compatibility. As backends are converted they can | |
1044 | arrange to pass the right value (the right value is the | |
1045 | size of a function pointer if gcc uses collect2 for the | |
1046 | object file format, zero if it does not). | |
1047 | FIXME: We pass the bitsize as 32, which is just plain | |
1048 | wrong, but actually doesn't matter very much. */ | |
da6b2d99 ILT |
1049 | if (! (_bfd_generic_link_add_one_symbol |
1050 | (info, abfd, name, p->flags, bfd_get_section (p), | |
6e07e54f | 1051 | p->value, string, false, 0, 32, |
da6b2d99 ILT |
1052 | (struct bfd_link_hash_entry **) &h))) |
1053 | return false; | |
1054 | ||
1055 | /* Save the BFD symbol so that we don't lose any backend | |
1056 | specific information that may be attached to it. We only | |
1057 | want this one if it gives more information than the | |
1058 | existing one; we don't want to replace a defined symbol | |
1059 | with an undefined one. This routine may be called with a | |
1060 | hash table other than the generic hash table, so we only | |
1061 | do this if we are certain that the hash table is a | |
1062 | generic one. */ | |
1063 | if (info->hash->creator == abfd->xvec) | |
1064 | { | |
1065 | if (h->sym == (asymbol *) NULL | |
1066 | || (bfd_get_section (p) != &bfd_und_section | |
1067 | && (! bfd_is_com_section (bfd_get_section (p)) | |
1068 | || (bfd_get_section (h->sym) == &bfd_und_section)))) | |
c3156966 ILT |
1069 | { |
1070 | h->sym = p; | |
1071 | /* BSF_OLD_COMMON is a hack to support COFF reloc | |
1072 | reading, and it should go away when the COFF | |
1073 | linker is switched to the new version. */ | |
1074 | if (bfd_is_com_section (bfd_get_section (p))) | |
1075 | p->flags |= BSF_OLD_COMMON; | |
1076 | } | |
da6b2d99 ILT |
1077 | } |
1078 | } | |
1079 | } | |
1080 | ||
1081 | return true; | |
1082 | } | |
1083 | \f | |
1084 | /* We use a state table to deal with adding symbols from an object | |
1085 | file. The first index into the state table describes the symbol | |
1086 | from the object file. The second index into the state table is the | |
1087 | type of the symbol in the hash table. */ | |
1088 | ||
1089 | /* The symbol from the object file is turned into one of these row | |
1090 | values. */ | |
1091 | ||
1092 | enum link_row | |
1093 | { | |
1094 | UNDEF_ROW, /* Undefined. */ | |
1095 | UNDEFW_ROW, /* Weak undefined. */ | |
1096 | DEF_ROW, /* Defined. */ | |
1097 | DEFW_ROW, /* Weak defined. */ | |
1098 | COMMON_ROW, /* Common. */ | |
1099 | INDR_ROW, /* Indirect. */ | |
1100 | WARN_ROW, /* Warning. */ | |
1101 | SET_ROW /* Member of set. */ | |
1102 | }; | |
1103 | ||
1104 | /* The actions to take in the state table. */ | |
1105 | ||
1106 | enum link_action | |
1107 | { | |
1108 | FAIL, /* Abort. */ | |
1109 | UND, /* Mark symbol undefined. */ | |
1110 | WEAK, /* Mark symbol weak undefined. */ | |
1111 | DEF, /* Mark symbol defined. */ | |
1112 | COM, /* Mark symbol common. */ | |
1113 | CREF, /* Possibly warn about common reference to defined symbol. */ | |
1114 | CDEF, /* Define existing common symbol. */ | |
1115 | NOACT, /* No action. */ | |
1116 | BIG, /* Mark symbol common using largest size. */ | |
1117 | MDEF, /* Multiple definition error. */ | |
1118 | IND, /* Make indirect symbol. */ | |
1119 | SET, /* Add value to set. */ | |
1120 | MWARN, /* Make warning symbol. */ | |
1121 | WARN, /* Issue warning. */ | |
1122 | CYCLE, /* Repeat with symbol pointed to. */ | |
1123 | WARNC /* Issue warning and then CYCLE. */ | |
1124 | }; | |
1125 | ||
1126 | /* The state table itself. The first index is a link_row and the | |
1127 | second index is a bfd_link_hash_type. */ | |
1128 | ||
1129 | static const enum link_action link_action[8][7] = | |
1130 | { | |
1131 | /* current\prev new undef weak def com indr warn */ | |
1132 | /* UNDEF_ROW */ {UND, NOACT, NOACT, NOACT, NOACT, CYCLE, WARNC }, | |
1133 | /* UNDEFW_ROW */ {WEAK, WEAK, NOACT, NOACT, NOACT, CYCLE, WARNC }, | |
1134 | /* DEF_ROW */ {DEF, DEF, DEF, MDEF, CDEF, CYCLE, CYCLE }, | |
1135 | /* DEFW_ROW */ {DEF, DEF, DEF, NOACT, NOACT, CYCLE, CYCLE }, | |
1136 | /* COMMON_ROW */ {COM, COM, COM, CREF, BIG, CYCLE, WARNC }, | |
1137 | /* INDR_ROW */ {IND, IND, IND, MDEF, MDEF, MDEF, WARNC }, | |
1138 | /* WARN_ROW */ {MWARN, WARN, WARN, MWARN, MWARN, MWARN, NOACT }, | |
1139 | /* SET_ROW */ {SET, SET, SET, SET, SET, CYCLE, WARNC } | |
1140 | }; | |
1141 | ||
1142 | /* Add a symbol to the global hash table. | |
1143 | ABFD is the BFD the symbol comes from. | |
1144 | NAME is the name of the symbol. | |
1145 | FLAGS is the BSF_* bits associated with the symbol. | |
1146 | SECTION is the section in which the symbol is defined; this may be | |
1147 | bfd_und_section or bfd_com_section. | |
1148 | VALUE is the value of the symbol, relative to the section. | |
1149 | STRING is used for either an indirect symbol, in which case it is | |
1150 | the name of the symbol to indirect to, or a warning symbol, in | |
1151 | which case it is the warning string. | |
1152 | COPY is true if NAME or STRING must be copied into locally | |
1153 | allocated memory if they need to be saved. | |
6e07e54f ILT |
1154 | CONSTRUCTOR is true if we should automatically collect gcc |
1155 | constructor or destructor names. | |
1156 | BITSIZE is the number of bits in constructor or set entries. | |
da6b2d99 ILT |
1157 | HASHP, if not NULL, is a place to store the created hash table |
1158 | entry. */ | |
1159 | ||
1160 | boolean | |
1161 | _bfd_generic_link_add_one_symbol (info, abfd, name, flags, section, value, | |
6e07e54f | 1162 | string, copy, constructor, bitsize, hashp) |
da6b2d99 ILT |
1163 | struct bfd_link_info *info; |
1164 | bfd *abfd; | |
1165 | const char *name; | |
1166 | flagword flags; | |
1167 | asection *section; | |
1168 | bfd_vma value; | |
1169 | const char *string; | |
1170 | boolean copy; | |
6e07e54f ILT |
1171 | boolean constructor; |
1172 | unsigned int bitsize; | |
da6b2d99 ILT |
1173 | struct bfd_link_hash_entry **hashp; |
1174 | { | |
1175 | enum link_row row; | |
1176 | struct bfd_link_hash_entry *h; | |
1177 | boolean cycle; | |
1178 | ||
1179 | if (section == &bfd_ind_section | |
1180 | || (flags & BSF_INDIRECT) != 0) | |
1181 | row = INDR_ROW; | |
1182 | else if ((flags & BSF_WARNING) != 0) | |
1183 | row = WARN_ROW; | |
1184 | else if ((flags & BSF_CONSTRUCTOR) != 0) | |
1185 | row = SET_ROW; | |
1186 | else if (section == &bfd_und_section) | |
1187 | { | |
1188 | if ((flags & BSF_WEAK) != 0) | |
1189 | row = UNDEFW_ROW; | |
1190 | else | |
1191 | row = UNDEF_ROW; | |
1192 | } | |
1193 | else if ((flags & BSF_WEAK) != 0) | |
1194 | row = DEFW_ROW; | |
1195 | else if (bfd_is_com_section (section)) | |
1196 | row = COMMON_ROW; | |
1197 | else | |
1198 | row = DEF_ROW; | |
1199 | ||
1200 | h = bfd_link_hash_lookup (info->hash, name, true, copy, false); | |
1201 | if (h == (struct bfd_link_hash_entry *) NULL) | |
1202 | { | |
1203 | if (hashp != (struct bfd_link_hash_entry **) NULL) | |
1204 | *hashp = NULL; | |
1205 | return false; | |
1206 | } | |
1207 | ||
1208 | if (info->notice_hash != (struct bfd_hash_table *) NULL | |
1209 | && (bfd_hash_lookup (info->notice_hash, name, false, false) | |
1210 | != (struct bfd_hash_entry *) NULL)) | |
1211 | { | |
1212 | if (! (*info->callbacks->notice) (info, name, abfd, section, value)) | |
1213 | return false; | |
1214 | } | |
1215 | ||
1216 | if (hashp != (struct bfd_link_hash_entry **) NULL) | |
1217 | *hashp = h; | |
1218 | ||
1219 | do | |
1220 | { | |
1221 | enum link_action action; | |
1222 | ||
1223 | cycle = false; | |
1224 | action = link_action[(int) row][(int) h->type]; | |
1225 | switch (action) | |
1226 | { | |
1227 | case FAIL: | |
1228 | abort (); | |
1229 | case UND: | |
1230 | h->type = bfd_link_hash_undefined; | |
1231 | h->u.undef.abfd = abfd; | |
1232 | bfd_link_add_undef (info->hash, h); | |
1233 | break; | |
1234 | case WEAK: | |
1235 | h->type = bfd_link_hash_weak; | |
1236 | h->u.undef.abfd = abfd; | |
1237 | break; | |
1238 | case CDEF: | |
1239 | BFD_ASSERT (h->type == bfd_link_hash_common); | |
1240 | if (! ((*info->callbacks->multiple_common) | |
1241 | (info, name, | |
1242 | h->u.c.section->owner, bfd_link_hash_common, h->u.c.size, | |
1243 | abfd, bfd_link_hash_defined, (bfd_vma) 0))) | |
1244 | return false; | |
1245 | /* Fall through. */ | |
1246 | case DEF: | |
1247 | h->type = bfd_link_hash_defined; | |
1248 | h->u.def.section = section; | |
1249 | h->u.def.value = value; | |
6e07e54f ILT |
1250 | |
1251 | /* If we have been asked to, we act like collect2 and | |
1252 | identify all functions that might be global constructors | |
1253 | and destructors and pass them up in a callback. We only | |
1254 | do this for certain object file types, since many object | |
1255 | file types can handle this automatically. */ | |
1256 | if (constructor && name[0] == '_') | |
1257 | { | |
1258 | const char *s; | |
1259 | ||
1260 | /* A constructor or destructor name starts like this: | |
1261 | _+GLOBAL_[_.$][ID][_.$] | |
1262 | where the first [_.$] and the second are the same | |
1263 | character (we accept any character there, in case a | |
1264 | new object file format comes along with even worse | |
1265 | naming restrictions). */ | |
1266 | ||
1267 | #define CONS_PREFIX "GLOBAL_" | |
1268 | #define CONS_PREFIX_LEN (sizeof CONS_PREFIX - 1) | |
1269 | ||
1270 | s = name + 1; | |
1271 | while (*s == '_') | |
1272 | ++s; | |
1273 | if (s[0] == 'G' | |
1274 | && strncmp (s, CONS_PREFIX, CONS_PREFIX_LEN - 1) == 0) | |
1275 | { | |
1276 | char c; | |
1277 | ||
1278 | c = s[CONS_PREFIX_LEN + 1]; | |
1279 | if ((c == 'I' || c == 'D') | |
1280 | && s[CONS_PREFIX_LEN] == s[CONS_PREFIX_LEN + 2]) | |
1281 | { | |
1282 | if (! ((*info->callbacks->constructor) | |
1283 | (info, | |
1284 | c == 'I' ? true : false, bitsize, | |
1285 | name, abfd, section, value))) | |
1286 | return false; | |
1287 | } | |
1288 | } | |
1289 | } | |
1290 | ||
da6b2d99 ILT |
1291 | break; |
1292 | case COM: | |
1293 | if (h->type == bfd_link_hash_new) | |
1294 | bfd_link_add_undef (info->hash, h); | |
1295 | h->type = bfd_link_hash_common; | |
1296 | h->u.c.size = value; | |
1297 | if (section == &bfd_com_section) | |
a20bdb43 ILT |
1298 | { |
1299 | h->u.c.section = bfd_make_section_old_way (abfd, "COMMON"); | |
1300 | h->u.c.section->flags = SEC_ALLOC; | |
1301 | } | |
da6b2d99 | 1302 | else if (section->owner != abfd) |
a20bdb43 ILT |
1303 | { |
1304 | h->u.c.section = bfd_make_section_old_way (abfd, section->name); | |
1305 | h->u.c.section->flags = SEC_ALLOC; | |
1306 | } | |
da6b2d99 ILT |
1307 | else |
1308 | h->u.c.section = section; | |
1309 | break; | |
1310 | case NOACT: | |
1311 | break; | |
1312 | case BIG: | |
1313 | BFD_ASSERT (h->type == bfd_link_hash_common); | |
1314 | if (! ((*info->callbacks->multiple_common) | |
1315 | (info, name, | |
1316 | h->u.c.section->owner, bfd_link_hash_common, h->u.c.size, | |
1317 | abfd, bfd_link_hash_common, value))) | |
1318 | return false; | |
1319 | if (value > h->u.c.size) | |
1320 | h->u.c.size = value; | |
da6b2d99 ILT |
1321 | break; |
1322 | case CREF: | |
1323 | BFD_ASSERT (h->type == bfd_link_hash_defined); | |
1324 | if (! ((*info->callbacks->multiple_common) | |
1325 | (info, name, | |
1326 | h->u.def.section->owner, bfd_link_hash_defined, (bfd_vma) 0, | |
1327 | abfd, bfd_link_hash_common, value))) | |
1328 | return false; | |
1329 | break; | |
1330 | case MDEF: | |
1331 | { | |
1332 | asection *msec; | |
1333 | bfd_vma mval; | |
1334 | ||
1335 | switch (h->type) | |
1336 | { | |
1337 | case bfd_link_hash_defined: | |
1338 | msec = h->u.def.section; | |
1339 | mval = h->u.def.value; | |
1340 | break; | |
1341 | case bfd_link_hash_common: | |
1342 | msec = &bfd_com_section; | |
1343 | mval = h->u.c.size; | |
1344 | break; | |
1345 | case bfd_link_hash_indirect: | |
1346 | msec = &bfd_ind_section; | |
1347 | mval = 0; | |
1348 | break; | |
1349 | default: | |
1350 | abort (); | |
1351 | } | |
1352 | ||
1353 | if (! ((*info->callbacks->multiple_definition) | |
1354 | (info, name, msec->owner, msec, mval, abfd, section, | |
1355 | value))) | |
1356 | return false; | |
1357 | } | |
1358 | break; | |
1359 | case IND: | |
1360 | { | |
1361 | struct bfd_link_hash_entry *inh; | |
1362 | ||
1363 | /* STRING is the name of the symbol we want to indirect | |
1364 | to. */ | |
1365 | inh = bfd_link_hash_lookup (info->hash, string, true, copy, | |
1366 | false); | |
1367 | if (inh == (struct bfd_link_hash_entry *) NULL) | |
1368 | return false; | |
1369 | if (inh->type == bfd_link_hash_new) | |
1370 | { | |
1371 | inh->type = bfd_link_hash_undefined; | |
1372 | inh->u.undef.abfd = abfd; | |
1373 | bfd_link_add_undef (info->hash, inh); | |
1374 | } | |
1375 | h->type = bfd_link_hash_indirect; | |
1376 | h->u.i.link = inh; | |
1377 | } | |
1378 | break; | |
1379 | case SET: | |
6e07e54f ILT |
1380 | if (! (*info->callbacks->add_to_set) (info, h, bitsize, abfd, |
1381 | section, value)) | |
da6b2d99 ILT |
1382 | return false; |
1383 | break; | |
1384 | case WARN: | |
1385 | case WARNC: | |
1386 | if (h->u.i.warning != NULL) | |
1387 | { | |
1388 | if (! (*info->callbacks->warning) (info, h->u.i.warning)) | |
1389 | return false; | |
1390 | /* Only issue a warning once. */ | |
1391 | h->u.i.warning = NULL; | |
1392 | } | |
1393 | if (action == WARN) | |
1394 | break; | |
1395 | /* Fall through. */ | |
1396 | case CYCLE: | |
1397 | h = h->u.i.link; | |
1398 | cycle = true; | |
1399 | break; | |
1400 | case MWARN: | |
1401 | { | |
1402 | struct bfd_link_hash_entry *sub; | |
1403 | ||
1404 | /* STRING is the warning to give. */ | |
1405 | sub = ((struct bfd_link_hash_entry *) | |
1406 | bfd_hash_allocate (&info->hash->table, | |
1407 | sizeof (struct bfd_link_hash_entry))); | |
1408 | *sub = *h; | |
1409 | h->type = bfd_link_hash_warning; | |
1410 | h->u.i.link = sub; | |
1411 | if (! copy) | |
1412 | h->u.i.warning = string; | |
1413 | else | |
1414 | { | |
1415 | char *w; | |
1416 | ||
1417 | w = bfd_hash_allocate (&info->hash->table, | |
1418 | strlen (string) + 1); | |
1419 | strcpy (w, string); | |
1420 | h->u.i.warning = w; | |
1421 | } | |
1422 | } | |
1423 | break; | |
1424 | } | |
1425 | } | |
1426 | while (cycle); | |
1427 | ||
1428 | return true; | |
1429 | } | |
1430 | \f | |
1431 | /* Generic final link routine. */ | |
1432 | ||
1433 | boolean | |
1434 | _bfd_generic_final_link (abfd, info) | |
1435 | bfd *abfd; | |
1436 | struct bfd_link_info *info; | |
1437 | { | |
1438 | bfd *sub; | |
1439 | asection *o; | |
1440 | struct bfd_link_order *p; | |
1441 | size_t outsymalloc; | |
1442 | struct generic_write_global_symbol_info wginfo; | |
1443 | ||
1444 | abfd->outsymbols = (asymbol **) NULL; | |
1445 | abfd->symcount = 0; | |
1446 | outsymalloc = 0; | |
1447 | ||
1448 | /* Build the output symbol table. This also reads in the symbols | |
1449 | for all the input BFDs, keeping them in the outsymbols field. */ | |
1450 | for (sub = info->input_bfds; sub != (bfd *) NULL; sub = sub->link_next) | |
1451 | if (! _bfd_generic_link_output_symbols (abfd, sub, info, &outsymalloc)) | |
1452 | return false; | |
1453 | ||
1454 | /* Accumulate the global symbols. */ | |
1455 | wginfo.output_bfd = abfd; | |
1456 | wginfo.psymalloc = &outsymalloc; | |
1457 | _bfd_generic_link_hash_traverse (_bfd_generic_hash_table (info), | |
1458 | _bfd_generic_link_write_global_symbol, | |
1459 | (PTR) &wginfo); | |
1460 | ||
1461 | if (info->relocateable) | |
1462 | { | |
1463 | /* Allocate space for the output relocs for each section. */ | |
1464 | for (o = abfd->sections; | |
1465 | o != (asection *) NULL; | |
1466 | o = o->next) | |
1467 | { | |
1468 | o->reloc_count = 0; | |
1469 | for (p = o->link_order_head; | |
1470 | p != (struct bfd_link_order *) NULL; | |
1471 | p = p->next) | |
1472 | { | |
1473 | if (p->type == bfd_indirect_link_order) | |
1474 | { | |
1475 | asection *input_section; | |
1476 | bfd *input_bfd; | |
1477 | bfd_size_type relsize; | |
1478 | arelent **relocs; | |
1479 | bfd_size_type reloc_count; | |
1480 | ||
1481 | input_section = p->u.indirect.section; | |
1482 | input_bfd = input_section->owner; | |
1483 | relsize = bfd_get_reloc_upper_bound (input_bfd, | |
1484 | input_section); | |
1485 | relocs = (arelent **) bfd_xmalloc (relsize); | |
1486 | reloc_count = | |
1487 | bfd_canonicalize_reloc (input_bfd, input_section, | |
1488 | relocs, | |
1489 | bfd_get_outsymbols (input_bfd)); | |
1490 | BFD_ASSERT (reloc_count == input_section->reloc_count); | |
1491 | o->reloc_count += reloc_count; | |
1492 | free (relocs); | |
1493 | } | |
1494 | } | |
1495 | if (o->reloc_count > 0) | |
1496 | { | |
1497 | o->orelocation = ((arelent **) | |
1498 | bfd_alloc (abfd, | |
1499 | (o->reloc_count | |
1500 | * sizeof (arelent *)))); | |
1501 | /* Reset the count so that it can be used as an index | |
1502 | when putting in the output relocs. */ | |
1503 | o->reloc_count = 0; | |
1504 | } | |
1505 | } | |
1506 | } | |
1507 | ||
1508 | /* Handle all the link order information for the sections. */ | |
1509 | for (o = abfd->sections; | |
1510 | o != (asection *) NULL; | |
1511 | o = o->next) | |
1512 | { | |
1513 | for (p = o->link_order_head; | |
1514 | p != (struct bfd_link_order *) NULL; | |
1515 | p = p->next) | |
1516 | { | |
6e07e54f ILT |
1517 | if (! _bfd_default_link_order (abfd, info, o, p)) |
1518 | return false; | |
da6b2d99 ILT |
1519 | } |
1520 | } | |
1521 | ||
1522 | return true; | |
1523 | } | |
1524 | ||
1525 | /* Add an output symbol to the output BFD. */ | |
1526 | ||
1527 | static boolean | |
1528 | generic_add_output_symbol (output_bfd, psymalloc, sym) | |
1529 | bfd *output_bfd; | |
1530 | size_t *psymalloc; | |
1531 | asymbol *sym; | |
1532 | { | |
1533 | if (output_bfd->symcount >= *psymalloc) | |
1534 | { | |
1535 | asymbol **newsyms; | |
1536 | ||
1537 | if (*psymalloc == 0) | |
1538 | *psymalloc = 124; | |
1539 | else | |
1540 | *psymalloc *= 2; | |
1541 | if (output_bfd->outsymbols == (asymbol **) NULL) | |
1542 | newsyms = (asymbol **) malloc (*psymalloc * sizeof (asymbol *)); | |
1543 | else | |
1544 | newsyms = (asymbol **) realloc (output_bfd->outsymbols, | |
1545 | *psymalloc * sizeof (asymbol *)); | |
1546 | if (newsyms == (asymbol **) NULL) | |
1547 | { | |
1548 | bfd_error = no_memory; | |
1549 | return false; | |
1550 | } | |
1551 | output_bfd->outsymbols = newsyms; | |
1552 | } | |
1553 | ||
1554 | output_bfd->outsymbols[output_bfd->symcount] = sym; | |
1555 | ++output_bfd->symcount; | |
1556 | ||
1557 | return true; | |
1558 | } | |
1559 | ||
1560 | /* Handle the symbols for an input BFD. */ | |
1561 | ||
1562 | boolean | |
1563 | _bfd_generic_link_output_symbols (output_bfd, input_bfd, info, psymalloc) | |
1564 | bfd *output_bfd; | |
1565 | bfd *input_bfd; | |
1566 | struct bfd_link_info *info; | |
1567 | size_t *psymalloc; | |
1568 | { | |
1569 | size_t symsize; | |
1570 | asymbol **sym_ptr; | |
1571 | asymbol **sym_end; | |
1572 | ||
1573 | symsize = get_symtab_upper_bound (input_bfd); | |
1574 | input_bfd->outsymbols = (asymbol **) bfd_alloc (input_bfd, symsize); | |
1575 | input_bfd->symcount = bfd_canonicalize_symtab (input_bfd, | |
1576 | input_bfd->outsymbols); | |
1577 | ||
1578 | /* Create a filename symbol if we are supposed to. */ | |
1579 | if (info->create_object_symbols_section != (asection *) NULL) | |
1580 | { | |
1581 | asection *sec; | |
1582 | ||
1583 | for (sec = input_bfd->sections; | |
1584 | sec != (asection *) NULL; | |
1585 | sec = sec->next) | |
1586 | { | |
1587 | if (sec->output_section == info->create_object_symbols_section) | |
1588 | { | |
1589 | asymbol *newsym; | |
1590 | ||
1591 | newsym = bfd_make_empty_symbol (input_bfd); | |
1592 | newsym->name = input_bfd->filename; | |
1593 | newsym->value = 0; | |
1594 | newsym->flags = BSF_LOCAL | BSF_FILE; | |
1595 | newsym->section = sec; | |
1596 | ||
1597 | if (! generic_add_output_symbol (output_bfd, psymalloc, | |
1598 | newsym)) | |
1599 | return false; | |
1600 | ||
1601 | break; | |
1602 | } | |
1603 | } | |
1604 | } | |
1605 | ||
1606 | /* Adjust the values of the globally visible symbols, and write out | |
1607 | local symbols. */ | |
1608 | sym_ptr = bfd_get_outsymbols (input_bfd); | |
1609 | sym_end = sym_ptr + bfd_get_symcount (input_bfd); | |
1610 | for (; sym_ptr < sym_end; sym_ptr++) | |
1611 | { | |
1612 | asymbol *sym; | |
1613 | struct generic_link_hash_entry *h; | |
1614 | boolean output; | |
1615 | ||
1616 | h = (struct generic_link_hash_entry *) NULL; | |
1617 | sym = *sym_ptr; | |
1618 | if ((sym->flags & (BSF_INDIRECT | |
1619 | | BSF_WARNING | |
1620 | | BSF_GLOBAL | |
1621 | | BSF_CONSTRUCTOR | |
1622 | | BSF_WEAK)) != 0 | |
1623 | || bfd_get_section (sym) == &bfd_und_section | |
1624 | || bfd_is_com_section (bfd_get_section (sym)) | |
1625 | || bfd_get_section (sym) == &bfd_ind_section) | |
1626 | { | |
1627 | h = _bfd_generic_link_hash_lookup (_bfd_generic_hash_table (info), | |
1628 | bfd_asymbol_name (sym), | |
1629 | false, false, true); | |
1630 | if (h != (struct generic_link_hash_entry *) NULL) | |
1631 | { | |
1632 | /* Force all references to this symbol to point to | |
1633 | the same area in memory. It is possible that | |
1634 | this routine will be called with a hash table | |
1635 | other than a generic hash table, so we double | |
1636 | check that. */ | |
1637 | if (info->hash->creator == input_bfd->xvec) | |
1638 | { | |
1639 | if (h->sym != (asymbol *) NULL) | |
1640 | *sym_ptr = sym = h->sym; | |
1641 | } | |
1642 | ||
1643 | switch (h->root.type) | |
1644 | { | |
1645 | default: | |
1646 | case bfd_link_hash_new: | |
1647 | abort (); | |
1648 | case bfd_link_hash_undefined: | |
1649 | case bfd_link_hash_weak: | |
1650 | break; | |
1651 | case bfd_link_hash_defined: | |
1652 | sym->value = h->root.u.def.value; | |
1653 | sym->section = h->root.u.def.section; | |
1654 | sym->flags |= BSF_GLOBAL; | |
1655 | break; | |
1656 | case bfd_link_hash_common: | |
1657 | sym->value = h->root.u.c.size; | |
1658 | sym->flags |= BSF_GLOBAL; | |
1659 | /* We do not set the section of the symbol to | |
1660 | c.section. c.section is saved so that we know | |
1661 | where to allocate the symbol if we define it. In | |
1662 | this case the type is still bfd_link_hash_common, | |
1663 | so we did not define it, so we do not want to use | |
1664 | that section. */ | |
1665 | BFD_ASSERT (bfd_is_com_section (sym->section)); | |
1666 | break; | |
1667 | } | |
1668 | } | |
1669 | } | |
1670 | ||
1671 | /* This switch is straight from the old code in | |
1672 | write_file_locals in ldsym.c. */ | |
1673 | if (info->strip == strip_some | |
1674 | && (bfd_hash_lookup (info->keep_hash, bfd_asymbol_name (sym), | |
1675 | false, false) | |
1676 | == (struct bfd_hash_entry *) NULL)) | |
1677 | output = false; | |
1678 | else if ((sym->flags & (BSF_GLOBAL | BSF_WEAK)) != 0) | |
1679 | { | |
1680 | /* If this symbol is marked as occurring now, rather | |
1681 | than at the end, output it now. This is used for | |
1682 | COFF C_EXT FCN symbols. FIXME: There must be a | |
1683 | better way. */ | |
1684 | if (bfd_asymbol_bfd (sym) == input_bfd | |
1685 | && (sym->flags & BSF_NOT_AT_END) != 0) | |
1686 | output = true; | |
1687 | else | |
1688 | output = false; | |
1689 | } | |
1690 | else if (sym->section == &bfd_ind_section) | |
1691 | output = false; | |
1692 | else if ((sym->flags & BSF_DEBUGGING) != 0) | |
1693 | { | |
1694 | if (info->strip == strip_none) | |
1695 | output = true; | |
1696 | else | |
1697 | output = false; | |
1698 | } | |
1699 | else if (sym->section == &bfd_und_section | |
1700 | || bfd_is_com_section (sym->section)) | |
1701 | output = false; | |
1702 | else if ((sym->flags & BSF_LOCAL) != 0) | |
1703 | { | |
1704 | if ((sym->flags & BSF_WARNING) != 0) | |
1705 | output = false; | |
1706 | else | |
1707 | { | |
1708 | switch (info->discard) | |
1709 | { | |
1710 | default: | |
1711 | case discard_all: | |
1712 | output = false; | |
1713 | break; | |
1714 | case discard_l: | |
1715 | if (bfd_asymbol_name (sym)[0] == info->lprefix[0] | |
1716 | && (info->lprefix_len == 1 | |
1717 | || strncmp (bfd_asymbol_name (sym), info->lprefix, | |
1718 | info->lprefix_len) == 0)) | |
1719 | output = false; | |
1720 | else | |
1721 | output = true; | |
1722 | break; | |
1723 | case discard_none: | |
1724 | output = true; | |
1725 | break; | |
1726 | } | |
1727 | } | |
1728 | } | |
1729 | else if ((sym->flags & BSF_CONSTRUCTOR)) | |
1730 | { | |
1731 | if (info->strip != strip_all) | |
1732 | output = true; | |
1733 | else | |
1734 | output = false; | |
1735 | } | |
1736 | else | |
1737 | abort (); | |
1738 | ||
1739 | if (output) | |
1740 | { | |
1741 | if (! generic_add_output_symbol (output_bfd, psymalloc, sym)) | |
1742 | return false; | |
1743 | if (h != (struct generic_link_hash_entry *) NULL) | |
1744 | h->root.written = true; | |
1745 | } | |
1746 | } | |
1747 | ||
1748 | return true; | |
1749 | } | |
1750 | ||
1751 | /* Write out a global symbol, if it hasn't already been written out. | |
1752 | This is called for each symbol in the hash table. */ | |
1753 | ||
1754 | boolean | |
1755 | _bfd_generic_link_write_global_symbol (h, data) | |
1756 | struct generic_link_hash_entry *h; | |
1757 | PTR data; | |
1758 | { | |
1759 | struct generic_write_global_symbol_info *wginfo = | |
1760 | (struct generic_write_global_symbol_info *) data; | |
1761 | asymbol *sym; | |
1762 | ||
1763 | if (h->root.written) | |
1764 | return true; | |
1765 | ||
1766 | if (h->sym != (asymbol *) NULL) | |
1767 | { | |
1768 | sym = h->sym; | |
1769 | BFD_ASSERT (strcmp (bfd_asymbol_name (sym), h->root.root.string) == 0); | |
1770 | } | |
1771 | else | |
1772 | { | |
1773 | sym = bfd_make_empty_symbol (wginfo->output_bfd); | |
1774 | sym->name = h->root.root.string; | |
1775 | sym->flags = 0; | |
1776 | } | |
1777 | ||
1778 | switch (h->root.type) | |
1779 | { | |
1780 | default: | |
1781 | case bfd_link_hash_new: | |
1782 | abort (); | |
1783 | case bfd_link_hash_undefined: | |
1784 | sym->section = &bfd_und_section; | |
1785 | sym->value = 0; | |
1786 | break; | |
1787 | case bfd_link_hash_weak: | |
1788 | sym->section = &bfd_und_section; | |
1789 | sym->value = 0; | |
1790 | sym->flags |= BSF_WEAK; | |
1791 | case bfd_link_hash_defined: | |
1792 | sym->section = h->root.u.def.section; | |
1793 | sym->value = h->root.u.def.value; | |
1794 | break; | |
1795 | case bfd_link_hash_common: | |
1796 | sym->value = h->root.u.c.size; | |
1797 | /* Do not set the section; see _bfd_generic_link_output_symbols. */ | |
1798 | BFD_ASSERT (bfd_is_com_section (sym->section)); | |
1799 | break; | |
1800 | case bfd_link_hash_indirect: | |
1801 | case bfd_link_hash_warning: | |
1802 | /* FIXME: What should we do here? */ | |
1803 | break; | |
1804 | } | |
1805 | ||
1806 | sym->flags |= BSF_GLOBAL; | |
1807 | ||
1808 | if (! generic_add_output_symbol (wginfo->output_bfd, wginfo->psymalloc, | |
1809 | sym)) | |
1810 | { | |
1811 | /* FIXME: No way to return failure. */ | |
1812 | abort (); | |
1813 | } | |
1814 | ||
1815 | h->root.written = true; | |
1816 | ||
1817 | return true; | |
1818 | } | |
da6b2d99 ILT |
1819 | \f |
1820 | /* Allocate a new link_order for a section. */ | |
1821 | ||
1822 | struct bfd_link_order * | |
1823 | bfd_new_link_order (abfd, section) | |
1824 | bfd *abfd; | |
1825 | asection *section; | |
1826 | { | |
1827 | struct bfd_link_order *new; | |
1828 | ||
1829 | new = ((struct bfd_link_order *) | |
1830 | bfd_alloc_by_size_t (abfd, sizeof (struct bfd_link_order))); | |
1831 | ||
1832 | new->type = bfd_undefined_link_order; | |
1833 | new->offset = 0; | |
1834 | new->size = 0; | |
1835 | new->next = (struct bfd_link_order *) NULL; | |
1836 | ||
1837 | if (section->link_order_tail != (struct bfd_link_order *) NULL) | |
1838 | section->link_order_tail->next = new; | |
1839 | else | |
1840 | section->link_order_head = new; | |
1841 | section->link_order_tail = new; | |
1842 | ||
1843 | return new; | |
1844 | } | |
1845 | ||
1846 | /* Default link order processing routine. */ | |
1847 | ||
1848 | boolean | |
1849 | _bfd_default_link_order (abfd, info, sec, link_order) | |
1850 | bfd *abfd; | |
1851 | struct bfd_link_info *info; | |
1852 | asection *sec; | |
1853 | struct bfd_link_order *link_order; | |
1854 | { | |
1855 | switch (link_order->type) | |
1856 | { | |
1857 | case bfd_undefined_link_order: | |
1858 | default: | |
1859 | abort (); | |
1860 | case bfd_indirect_link_order: | |
6e07e54f | 1861 | return default_indirect_link_order (abfd, info, sec, link_order); |
da6b2d99 ILT |
1862 | case bfd_fill_link_order: |
1863 | return default_fill_link_order (abfd, info, sec, link_order); | |
1864 | } | |
1865 | } | |
1866 | ||
1867 | /* Default routine to handle a bfd_fill_link_order. */ | |
1868 | ||
6e07e54f | 1869 | /*ARGSUSED*/ |
da6b2d99 ILT |
1870 | static boolean |
1871 | default_fill_link_order (abfd, info, sec, link_order) | |
1872 | bfd *abfd; | |
1873 | struct bfd_link_info *info; | |
1874 | asection *sec; | |
1875 | struct bfd_link_order *link_order; | |
1876 | { | |
1877 | size_t size; | |
1878 | char *space; | |
1879 | size_t i; | |
1880 | int fill; | |
1881 | ||
1882 | BFD_ASSERT ((sec->flags & SEC_HAS_CONTENTS) != 0); | |
1883 | ||
1884 | size = (size_t) link_order->size; | |
1885 | space = (char *) alloca (size); | |
1886 | fill = link_order->u.fill.value; | |
1887 | for (i = 0; i < size; i += 2) | |
1888 | space[i] = fill >> 8; | |
1889 | for (i = 1; i < size; i += 2) | |
1890 | space[i] = fill; | |
1891 | return bfd_set_section_contents (abfd, sec, space, | |
1892 | (file_ptr) link_order->offset, | |
1893 | link_order->size); | |
1894 | } | |
6e07e54f ILT |
1895 | |
1896 | /* Default routine to handle a bfd_indirect_link_order. */ | |
1897 | ||
1898 | static boolean | |
1899 | default_indirect_link_order (output_bfd, info, output_section, link_order) | |
1900 | bfd *output_bfd; | |
1901 | struct bfd_link_info *info; | |
1902 | asection *output_section; | |
1903 | struct bfd_link_order *link_order; | |
1904 | { | |
1905 | asection *input_section; | |
1906 | bfd *input_bfd; | |
1907 | bfd_byte *contents; | |
1908 | ||
1909 | BFD_ASSERT ((output_section->flags & SEC_HAS_CONTENTS) != 0); | |
1910 | ||
1911 | if (link_order->size == 0) | |
1912 | return true; | |
1913 | ||
1914 | input_section = link_order->u.indirect.section; | |
1915 | input_bfd = input_section->owner; | |
1916 | ||
1917 | BFD_ASSERT (input_section->output_section == output_section); | |
1918 | BFD_ASSERT (input_section->output_offset == link_order->offset); | |
1919 | BFD_ASSERT (bfd_section_size (input_bfd, input_section) == link_order->size); | |
1920 | ||
1921 | if (info->relocateable | |
92f345b9 | 1922 | && input_section->reloc_count > 0 |
6e07e54f ILT |
1923 | && output_section->orelocation == (arelent **) NULL) |
1924 | { | |
1925 | /* Space has not been allocated for the output relocations. | |
1926 | This can happen when we are called by a specific backend | |
1927 | because somebody is attempting to link together different | |
1928 | types of object files. Handling this case correctly is | |
1929 | difficult, and sometimes impossible. */ | |
1930 | abort (); | |
1931 | } | |
1932 | ||
1933 | /* Get the canonical symbols. The generic linker will always have | |
1934 | retrieved them by this point, but we may be being called by a | |
1935 | specific linker when linking different types of object files | |
1936 | together. */ | |
1937 | if (bfd_get_outsymbols (input_bfd) == (asymbol **) NULL) | |
1938 | { | |
1939 | size_t symsize; | |
1940 | ||
1941 | symsize = get_symtab_upper_bound (input_bfd); | |
1942 | input_bfd->outsymbols = (asymbol **) bfd_alloc (input_bfd, symsize); | |
1943 | input_bfd->symcount = bfd_canonicalize_symtab (input_bfd, | |
1944 | input_bfd->outsymbols); | |
1945 | } | |
1946 | ||
1947 | /* Get and relocate the section contents. */ | |
1948 | contents = (bfd_byte *) alloca (bfd_section_size (input_bfd, input_section)); | |
1949 | contents = (bfd_get_relocated_section_contents | |
1950 | (output_bfd, info, link_order, contents, info->relocateable, | |
1951 | bfd_get_outsymbols (input_bfd))); | |
1952 | ||
1953 | /* Output the section contents. */ | |
1954 | if (! bfd_set_section_contents (output_bfd, output_section, (PTR) contents, | |
1955 | link_order->offset, link_order->size)) | |
1956 | return false; | |
1957 | ||
1958 | return true; | |
1959 | } |