ELF: Add support for unique section ID to assembler
[deliverable/binutils-gdb.git] / gas / config / obj-elf.c
1 /* ELF object file format
2 Copyright (C) 1992-2020 Free Software Foundation, Inc.
3
4 This file is part of GAS, the GNU Assembler.
5
6 GAS is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as
8 published by the Free Software Foundation; either version 3,
9 or (at your option) any later version.
10
11 GAS is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
14 the GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GAS; see the file COPYING. If not, write to the Free
18 Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
19 02110-1301, USA. */
20
21 #define OBJ_HEADER "obj-elf.h"
22 #include "as.h"
23 #include "safe-ctype.h"
24 #include "subsegs.h"
25 #include "obstack.h"
26 #include "dwarf2dbg.h"
27
28 #ifndef ECOFF_DEBUGGING
29 #define ECOFF_DEBUGGING 0
30 #else
31 #define NEED_ECOFF_DEBUG
32 #endif
33
34 #ifdef NEED_ECOFF_DEBUG
35 #include "ecoff.h"
36 #include "bfd/ecoff-bfd.h"
37 #endif
38
39 #ifdef TC_ALPHA
40 #include "elf/alpha.h"
41 #endif
42
43 #ifdef TC_MIPS
44 #include "elf/mips.h"
45 #endif
46
47 #ifdef TC_PPC
48 #include "elf/ppc.h"
49 #endif
50
51 #ifdef TC_I386
52 #include "elf/x86-64.h"
53 #endif
54
55 #ifdef TC_MEP
56 #include "elf/mep.h"
57 #endif
58
59 #ifdef TC_NIOS2
60 #include "elf/nios2.h"
61 #endif
62
63 #ifdef TC_PRU
64 #include "elf/pru.h"
65 #endif
66
67 static void obj_elf_line (int);
68 static void obj_elf_size (int);
69 static void obj_elf_type (int);
70 static void obj_elf_ident (int);
71 static void obj_elf_weak (int);
72 static void obj_elf_local (int);
73 static void obj_elf_visibility (int);
74 static void obj_elf_symver (int);
75 static void obj_elf_subsection (int);
76 static void obj_elf_popsection (int);
77 static void obj_elf_gnu_attribute (int);
78 static void obj_elf_tls_common (int);
79 static void obj_elf_lcomm (int);
80 static void obj_elf_struct (int);
81
82 static const pseudo_typeS elf_pseudo_table[] =
83 {
84 {"comm", obj_elf_common, 0},
85 {"common", obj_elf_common, 1},
86 {"ident", obj_elf_ident, 0},
87 {"lcomm", obj_elf_lcomm, 0},
88 {"local", obj_elf_local, 0},
89 {"previous", obj_elf_previous, 0},
90 {"section", obj_elf_section, 0},
91 {"section.s", obj_elf_section, 0},
92 {"sect", obj_elf_section, 0},
93 {"sect.s", obj_elf_section, 0},
94 {"pushsection", obj_elf_section, 1},
95 {"popsection", obj_elf_popsection, 0},
96 {"size", obj_elf_size, 0},
97 {"type", obj_elf_type, 0},
98 {"version", obj_elf_version, 0},
99 {"weak", obj_elf_weak, 0},
100
101 /* These define symbol visibility. */
102 {"internal", obj_elf_visibility, STV_INTERNAL},
103 {"hidden", obj_elf_visibility, STV_HIDDEN},
104 {"protected", obj_elf_visibility, STV_PROTECTED},
105
106 /* These are used for stabs-in-elf configurations. */
107 {"line", obj_elf_line, 0},
108
109 /* This is a GNU extension to handle symbol versions. */
110 {"symver", obj_elf_symver, 0},
111
112 /* A GNU extension to change subsection only. */
113 {"subsection", obj_elf_subsection, 0},
114
115 /* These are GNU extensions to aid in garbage collecting C++ vtables. */
116 {"vtable_inherit", obj_elf_vtable_inherit, 0},
117 {"vtable_entry", obj_elf_vtable_entry, 0},
118
119 /* A GNU extension for object attributes. */
120 {"gnu_attribute", obj_elf_gnu_attribute, 0},
121
122 /* These are used for dwarf. */
123 {"2byte", cons, 2},
124 {"4byte", cons, 4},
125 {"8byte", cons, 8},
126 /* These are used for dwarf2. */
127 { "file", dwarf2_directive_file, 0 },
128 { "loc", dwarf2_directive_loc, 0 },
129 { "loc_mark_labels", dwarf2_directive_loc_mark_labels, 0 },
130
131 /* We need to trap the section changing calls to handle .previous. */
132 {"data", obj_elf_data, 0},
133 {"offset", obj_elf_struct, 0},
134 {"struct", obj_elf_struct, 0},
135 {"text", obj_elf_text, 0},
136
137 {"tls_common", obj_elf_tls_common, 0},
138
139 /* End sentinel. */
140 {NULL, NULL, 0},
141 };
142
143 static const pseudo_typeS ecoff_debug_pseudo_table[] =
144 {
145 #ifdef NEED_ECOFF_DEBUG
146 /* COFF style debugging information for ECOFF. .ln is not used; .loc
147 is used instead. */
148 { "def", ecoff_directive_def, 0 },
149 { "dim", ecoff_directive_dim, 0 },
150 { "endef", ecoff_directive_endef, 0 },
151 { "file", ecoff_directive_file, 0 },
152 { "scl", ecoff_directive_scl, 0 },
153 { "tag", ecoff_directive_tag, 0 },
154 { "val", ecoff_directive_val, 0 },
155
156 /* COFF debugging requires pseudo-ops .size and .type, but ELF
157 already has meanings for those. We use .esize and .etype
158 instead. These are only generated by gcc anyhow. */
159 { "esize", ecoff_directive_size, 0 },
160 { "etype", ecoff_directive_type, 0 },
161
162 /* ECOFF specific debugging information. */
163 { "aent", ecoff_directive_ent, 1 },
164 { "begin", ecoff_directive_begin, 0 },
165 { "bend", ecoff_directive_bend, 0 },
166 { "end", ecoff_directive_end, 0 },
167 { "ent", ecoff_directive_ent, 0 },
168 { "fmask", ecoff_directive_fmask, 0 },
169 { "frame", ecoff_directive_frame, 0 },
170 { "loc", ecoff_directive_loc, 0 },
171 { "mask", ecoff_directive_mask, 0 },
172
173 /* Other ECOFF directives. */
174 { "extern", ecoff_directive_extern, 0 },
175
176 /* These are used on Irix. I don't know how to implement them. */
177 { "alias", s_ignore, 0 },
178 { "bgnb", s_ignore, 0 },
179 { "endb", s_ignore, 0 },
180 { "lab", s_ignore, 0 },
181 { "noalias", s_ignore, 0 },
182 { "verstamp", s_ignore, 0 },
183 { "vreg", s_ignore, 0 },
184 #endif
185
186 {NULL, NULL, 0} /* end sentinel */
187 };
188
189 #undef NO_RELOC
190 #include "aout/aout64.h"
191
192 /* This is called when the assembler starts. */
193
194 asection *elf_com_section_ptr;
195
196 void
197 elf_begin (void)
198 {
199 asection *s;
200
201 /* Add symbols for the known sections to the symbol table. */
202 s = bfd_get_section_by_name (stdoutput, TEXT_SECTION_NAME);
203 symbol_table_insert (section_symbol (s));
204 s = bfd_get_section_by_name (stdoutput, DATA_SECTION_NAME);
205 symbol_table_insert (section_symbol (s));
206 s = bfd_get_section_by_name (stdoutput, BSS_SECTION_NAME);
207 symbol_table_insert (section_symbol (s));
208 elf_com_section_ptr = bfd_com_section_ptr;
209 }
210
211 void
212 elf_pop_insert (void)
213 {
214 pop_insert (elf_pseudo_table);
215 if (ECOFF_DEBUGGING)
216 pop_insert (ecoff_debug_pseudo_table);
217 }
218
219 static bfd_vma
220 elf_s_get_size (symbolS *sym)
221 {
222 return S_GET_SIZE (sym);
223 }
224
225 static void
226 elf_s_set_size (symbolS *sym, bfd_vma sz)
227 {
228 S_SET_SIZE (sym, sz);
229 }
230
231 static bfd_vma
232 elf_s_get_align (symbolS *sym)
233 {
234 return S_GET_ALIGN (sym);
235 }
236
237 static void
238 elf_s_set_align (symbolS *sym, bfd_vma align)
239 {
240 S_SET_ALIGN (sym, align);
241 }
242
243 int
244 elf_s_get_other (symbolS *sym)
245 {
246 return elf_symbol (symbol_get_bfdsym (sym))->internal_elf_sym.st_other;
247 }
248
249 static void
250 elf_s_set_other (symbolS *sym, int other)
251 {
252 S_SET_OTHER (sym, other);
253 }
254
255 static int
256 elf_sec_sym_ok_for_reloc (asection *sec)
257 {
258 return obj_sec_sym_ok_for_reloc (sec);
259 }
260
261 void
262 elf_file_symbol (const char *s, int appfile)
263 {
264 asymbol *bsym;
265
266 if (!appfile
267 || symbol_rootP == NULL
268 || (bsym = symbol_get_bfdsym (symbol_rootP)) == NULL
269 || (bsym->flags & BSF_FILE) == 0)
270 {
271 symbolS *sym;
272 size_t name_length;
273
274 sym = symbol_new (s, absolute_section, 0, NULL);
275 symbol_set_frag (sym, &zero_address_frag);
276
277 name_length = strlen (s);
278 if (name_length > strlen (S_GET_NAME (sym)))
279 {
280 obstack_grow (&notes, s, name_length + 1);
281 S_SET_NAME (sym, (const char *) obstack_finish (&notes));
282 }
283 else
284 strcpy ((char *) S_GET_NAME (sym), s);
285
286 symbol_get_bfdsym (sym)->flags |= BSF_FILE;
287
288 if (symbol_rootP != sym
289 && ((bsym = symbol_get_bfdsym (symbol_rootP)) == NULL
290 || (bsym->flags & BSF_FILE) == 0))
291 {
292 symbol_remove (sym, &symbol_rootP, &symbol_lastP);
293 symbol_insert (sym, symbol_rootP, &symbol_rootP, &symbol_lastP);
294 }
295
296 #ifdef DEBUG
297 verify_symbol_chain (symbol_rootP, symbol_lastP);
298 #endif
299 }
300
301 #ifdef NEED_ECOFF_DEBUG
302 ecoff_new_file (s, appfile);
303 #endif
304 }
305
306 /* Called from read.c:s_comm after we've parsed .comm symbol, size.
307 Parse a possible alignment value. */
308
309 symbolS *
310 elf_common_parse (int ignore ATTRIBUTE_UNUSED, symbolS *symbolP, addressT size)
311 {
312 addressT align = 0;
313 int is_local = symbol_get_obj (symbolP)->local;
314
315 if (*input_line_pointer == ',')
316 {
317 char *save = input_line_pointer;
318
319 input_line_pointer++;
320 SKIP_WHITESPACE ();
321
322 if (*input_line_pointer == '"')
323 {
324 /* For sparc. Accept .common symbol, length, "bss" */
325 input_line_pointer++;
326 /* Some use the dot, some don't. */
327 if (*input_line_pointer == '.')
328 input_line_pointer++;
329 /* Some say data, some say bss. */
330 if (strncmp (input_line_pointer, "bss\"", 4) == 0)
331 input_line_pointer += 4;
332 else if (strncmp (input_line_pointer, "data\"", 5) == 0)
333 input_line_pointer += 5;
334 else
335 {
336 char *p = input_line_pointer;
337 char c;
338
339 while (*--p != '"')
340 ;
341 while (!is_end_of_line[(unsigned char) *input_line_pointer])
342 if (*input_line_pointer++ == '"')
343 break;
344 c = *input_line_pointer;
345 *input_line_pointer = '\0';
346 as_bad (_("bad .common segment %s"), p);
347 *input_line_pointer = c;
348 ignore_rest_of_line ();
349 return NULL;
350 }
351 /* ??? Don't ask me why these are always global. */
352 is_local = 0;
353 }
354 else
355 {
356 input_line_pointer = save;
357 align = parse_align (is_local);
358 if (align == (addressT) -1)
359 return NULL;
360 }
361 }
362
363 if (is_local)
364 {
365 bss_alloc (symbolP, size, align);
366 S_CLEAR_EXTERNAL (symbolP);
367 }
368 else
369 {
370 S_SET_VALUE (symbolP, size);
371 S_SET_ALIGN (symbolP, align);
372 S_SET_EXTERNAL (symbolP);
373 S_SET_SEGMENT (symbolP, elf_com_section_ptr);
374 }
375
376 symbol_get_bfdsym (symbolP)->flags |= BSF_OBJECT;
377
378 return symbolP;
379 }
380
381 void
382 obj_elf_common (int is_common)
383 {
384 if (flag_mri && is_common)
385 s_mri_common (0);
386 else
387 s_comm_internal (0, elf_common_parse);
388 }
389
390 static void
391 obj_elf_tls_common (int ignore ATTRIBUTE_UNUSED)
392 {
393 symbolS *symbolP = s_comm_internal (0, elf_common_parse);
394
395 if (symbolP)
396 symbol_get_bfdsym (symbolP)->flags |= BSF_THREAD_LOCAL;
397 }
398
399 static void
400 obj_elf_lcomm (int ignore ATTRIBUTE_UNUSED)
401 {
402 symbolS *symbolP = s_comm_internal (0, s_lcomm_internal);
403
404 if (symbolP)
405 symbol_get_bfdsym (symbolP)->flags |= BSF_OBJECT;
406 }
407
408 static symbolS *
409 get_sym_from_input_line_and_check (void)
410 {
411 char *name;
412 char c;
413 symbolS *sym;
414
415 c = get_symbol_name (& name);
416 sym = symbol_find_or_make (name);
417 *input_line_pointer = c;
418 SKIP_WHITESPACE_AFTER_NAME ();
419
420 /* There is no symbol name if input_line_pointer has not moved. */
421 if (name == input_line_pointer)
422 as_bad (_("Missing symbol name in directive"));
423 return sym;
424 }
425
426 static void
427 obj_elf_local (int ignore ATTRIBUTE_UNUSED)
428 {
429 int c;
430 symbolS *symbolP;
431
432 do
433 {
434 symbolP = get_sym_from_input_line_and_check ();
435 c = *input_line_pointer;
436 S_CLEAR_EXTERNAL (symbolP);
437 symbol_get_obj (symbolP)->local = 1;
438 if (c == ',')
439 {
440 input_line_pointer++;
441 SKIP_WHITESPACE ();
442 if (*input_line_pointer == '\n')
443 c = '\n';
444 }
445 }
446 while (c == ',');
447 demand_empty_rest_of_line ();
448 }
449
450 static void
451 obj_elf_weak (int ignore ATTRIBUTE_UNUSED)
452 {
453 int c;
454 symbolS *symbolP;
455
456 do
457 {
458 symbolP = get_sym_from_input_line_and_check ();
459 c = *input_line_pointer;
460 S_SET_WEAK (symbolP);
461 if (c == ',')
462 {
463 input_line_pointer++;
464 SKIP_WHITESPACE ();
465 if (*input_line_pointer == '\n')
466 c = '\n';
467 }
468 }
469 while (c == ',');
470 demand_empty_rest_of_line ();
471 }
472
473 static void
474 obj_elf_visibility (int visibility)
475 {
476 int c;
477 symbolS *symbolP;
478 asymbol *bfdsym;
479 elf_symbol_type *elfsym;
480
481 do
482 {
483 symbolP = get_sym_from_input_line_and_check ();
484
485 bfdsym = symbol_get_bfdsym (symbolP);
486 elfsym = elf_symbol_from (bfd_asymbol_bfd (bfdsym), bfdsym);
487
488 gas_assert (elfsym);
489
490 elfsym->internal_elf_sym.st_other &= ~3;
491 elfsym->internal_elf_sym.st_other |= visibility;
492
493 c = *input_line_pointer;
494 if (c == ',')
495 {
496 input_line_pointer ++;
497
498 SKIP_WHITESPACE ();
499
500 if (*input_line_pointer == '\n')
501 c = '\n';
502 }
503 }
504 while (c == ',');
505
506 demand_empty_rest_of_line ();
507 }
508
509 static segT previous_section;
510 static int previous_subsection;
511
512 struct section_stack
513 {
514 struct section_stack *next;
515 segT seg, prev_seg;
516 int subseg, prev_subseg;
517 };
518
519 static struct section_stack *section_stack;
520
521 static bfd_boolean
522 get_section (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *inf)
523 {
524 struct elf_section_match *match = (struct elf_section_match *) inf;
525 const char *gname = match->group_name;
526 const char *group_name = elf_group_name (sec);
527 unsigned int info = elf_section_data (sec)->this_hdr.sh_info;
528
529 return (info == match->info
530 && ((bfd_section_flags (sec) & SEC_ASSEMBLER_SECTION_ID)
531 == (match->flags & SEC_ASSEMBLER_SECTION_ID))
532 && sec->section_id == match->section_id
533 && (group_name == gname
534 || (group_name != NULL
535 && gname != NULL
536 && strcmp (group_name, gname) == 0)));
537 }
538
539 /* Handle the .section pseudo-op. This code supports two different
540 syntaxes.
541
542 The first is found on Solaris, and looks like
543 .section ".sec1",#alloc,#execinstr,#write
544 Here the names after '#' are the SHF_* flags to turn on for the
545 section. I'm not sure how it determines the SHT_* type (BFD
546 doesn't really give us control over the type, anyhow).
547
548 The second format is found on UnixWare, and probably most SVR4
549 machines, and looks like
550 .section .sec1,"a",@progbits
551 The quoted string may contain any combination of a, w, x, and
552 represents the SHF_* flags to turn on for the section. The string
553 beginning with '@' can be progbits or nobits. There should be
554 other possibilities, but I don't know what they are. In any case,
555 BFD doesn't really let us set the section type. */
556
557 void
558 obj_elf_change_section (const char *name,
559 unsigned int type,
560 bfd_vma attr,
561 int entsize,
562 struct elf_section_match *match_p,
563 int linkonce,
564 int push)
565 {
566 asection *old_sec;
567 segT sec;
568 flagword flags;
569 const struct elf_backend_data *bed;
570 const struct bfd_elf_special_section *ssect;
571
572 if (match_p == NULL)
573 {
574 static struct elf_section_match unused_match;
575 match_p = &unused_match;
576 }
577
578 #ifdef md_flush_pending_output
579 md_flush_pending_output ();
580 #endif
581
582 /* Switch to the section, creating it if necessary. */
583 if (push)
584 {
585 struct section_stack *elt;
586 elt = XNEW (struct section_stack);
587 elt->next = section_stack;
588 elt->seg = now_seg;
589 elt->prev_seg = previous_section;
590 elt->subseg = now_subseg;
591 elt->prev_subseg = previous_subsection;
592 section_stack = elt;
593 }
594 previous_section = now_seg;
595 previous_subsection = now_subseg;
596
597 old_sec = bfd_get_section_by_name_if (stdoutput, name, get_section,
598 (void *) match_p);
599 if (old_sec)
600 {
601 sec = old_sec;
602 subseg_set (sec, 0);
603 }
604 else
605 sec = subseg_force_new (name, 0);
606
607 bed = get_elf_backend_data (stdoutput);
608 ssect = (*bed->get_sec_type_attr) (stdoutput, sec);
609
610 if (ssect != NULL)
611 {
612 bfd_boolean override = FALSE;
613
614 if (type == SHT_NULL)
615 type = ssect->type;
616 else if (type != ssect->type)
617 {
618 if (old_sec == NULL
619 /* Some older versions of gcc will emit
620
621 .section .init_array,"aw",@progbits
622
623 for __attribute__ ((section (".init_array"))).
624 "@progbits" is incorrect. Also for x86-64 large bss
625 sections, some older versions of gcc will emit
626
627 .section .lbss,"aw",@progbits
628
629 "@progbits" is incorrect. */
630 #ifdef TC_I386
631 && (bed->s->arch_size != 64
632 || !(ssect->attr & SHF_X86_64_LARGE))
633 #endif
634 && ssect->type != SHT_INIT_ARRAY
635 && ssect->type != SHT_FINI_ARRAY
636 && ssect->type != SHT_PREINIT_ARRAY)
637 {
638 /* We allow to specify any type for a .note section. */
639 if (ssect->type != SHT_NOTE
640 /* Processor and application defined types are allowed too. */
641 && type < SHT_LOPROC)
642 as_warn (_("setting incorrect section type for %s"),
643 name);
644 }
645 else
646 {
647 as_warn (_("ignoring incorrect section type for %s"),
648 name);
649 type = ssect->type;
650 }
651 }
652
653 if (old_sec == NULL && ((attr & ~(SHF_MASKOS | SHF_MASKPROC))
654 & ~ssect->attr) != 0)
655 {
656 /* As a GNU extension, we permit a .note section to be
657 allocatable. If the linker sees an allocatable .note
658 section, it will create a PT_NOTE segment in the output
659 file. We also allow "x" for .note.GNU-stack. */
660 if (ssect->type == SHT_NOTE
661 && (attr == SHF_ALLOC || attr == SHF_EXECINSTR))
662 ;
663 /* Allow different SHF_MERGE and SHF_STRINGS if we have
664 something like .rodata.str. */
665 else if (ssect->suffix_length == -2
666 && name[ssect->prefix_length] == '.'
667 && (attr
668 & ~ssect->attr
669 & ~SHF_MERGE
670 & ~SHF_STRINGS) == 0)
671 ;
672 /* .interp, .strtab and .symtab can have SHF_ALLOC. */
673 else if (attr == SHF_ALLOC
674 && (strcmp (name, ".interp") == 0
675 || strcmp (name, ".strtab") == 0
676 || strcmp (name, ".symtab") == 0))
677 override = TRUE;
678 /* .note.GNU-stack can have SHF_EXECINSTR. */
679 else if (attr == SHF_EXECINSTR
680 && strcmp (name, ".note.GNU-stack") == 0)
681 override = TRUE;
682 #ifdef TC_ALPHA
683 /* A section on Alpha may have SHF_ALPHA_GPREL. */
684 else if ((attr & ~ssect->attr) == SHF_ALPHA_GPREL)
685 override = TRUE;
686 #endif
687 #ifdef TC_RX
688 else if (attr == (SHF_EXECINSTR | SHF_WRITE | SHF_ALLOC)
689 && (ssect->type == SHT_INIT_ARRAY
690 || ssect->type == SHT_FINI_ARRAY
691 || ssect->type == SHT_PREINIT_ARRAY))
692 /* RX init/fini arrays can and should have the "awx" attributes set. */
693 ;
694 #endif
695 else
696 {
697 if (match_p->group_name == NULL)
698 as_warn (_("setting incorrect section attributes for %s"),
699 name);
700 override = TRUE;
701 }
702 }
703
704 if (!override && old_sec == NULL)
705 attr |= ssect->attr;
706 }
707
708 /* Convert ELF type and flags to BFD flags. */
709 flags = (SEC_RELOC
710 | ((attr & SHF_WRITE) ? 0 : SEC_READONLY)
711 | ((attr & SHF_ALLOC) ? SEC_ALLOC : 0)
712 | (((attr & SHF_ALLOC) && type != SHT_NOBITS) ? SEC_LOAD : 0)
713 | ((attr & SHF_EXECINSTR) ? SEC_CODE : 0)
714 | ((attr & SHF_MERGE) ? SEC_MERGE : 0)
715 | ((attr & SHF_STRINGS) ? SEC_STRINGS : 0)
716 | ((attr & SHF_EXCLUDE) ? SEC_EXCLUDE: 0)
717 | ((attr & SHF_TLS) ? SEC_THREAD_LOCAL : 0));
718 #ifdef md_elf_section_flags
719 flags = md_elf_section_flags (flags, attr, type);
720 #endif
721
722 if (linkonce)
723 flags |= SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD;
724
725 if (old_sec == NULL)
726 {
727 symbolS *secsym;
728
729 if (type == SHT_NULL)
730 type = bfd_elf_get_default_section_type (flags);
731 elf_section_type (sec) = type;
732 elf_section_flags (sec) = attr;
733 elf_section_data (sec)->this_hdr.sh_info = match_p->info;
734
735 /* Prevent SEC_HAS_CONTENTS from being inadvertently set. */
736 if (type == SHT_NOBITS)
737 seg_info (sec)->bss = 1;
738
739 /* Set the section ID and flags. */
740 sec->section_id = match_p->section_id;
741 flags |= match_p->flags;
742
743 bfd_set_section_flags (sec, flags);
744 if (flags & SEC_MERGE)
745 sec->entsize = entsize;
746 elf_group_name (sec) = match_p->group_name;
747
748 /* Add a symbol for this section to the symbol table. */
749 secsym = symbol_find (name);
750 if (secsym != NULL)
751 symbol_set_bfdsym (secsym, sec->symbol);
752 else
753 symbol_table_insert (section_symbol (sec));
754 }
755 else
756 {
757 if (type != SHT_NULL
758 && (unsigned) type != elf_section_type (old_sec))
759 as_warn (_("ignoring changed section type for %s"), name);
760
761 if (attr != 0)
762 {
763 /* If section attributes are specified the second time we see a
764 particular section, then check that they are the same as we
765 saw the first time. */
766 if (((old_sec->flags ^ flags)
767 & (SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE
768 | SEC_EXCLUDE | SEC_SORT_ENTRIES | SEC_MERGE | SEC_STRINGS
769 | SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD
770 | SEC_THREAD_LOCAL)))
771 as_warn (_("ignoring changed section attributes for %s"), name);
772 else
773 /* FIXME: Maybe we should consider removing a previously set
774 processor or application specific attribute as suspicious ? */
775 elf_section_flags (sec) = attr;
776
777 if ((flags & SEC_MERGE) && old_sec->entsize != (unsigned) entsize)
778 as_warn (_("ignoring changed section entity size for %s"), name);
779 }
780 }
781
782 #ifdef md_elf_section_change_hook
783 md_elf_section_change_hook ();
784 #endif
785 }
786
787 static bfd_vma
788 obj_elf_parse_section_letters (char *str, size_t len,
789 bfd_boolean *is_clone, bfd_vma *gnu_attr)
790 {
791 bfd_vma attr = 0;
792 *is_clone = FALSE;
793
794 while (len > 0)
795 {
796 switch (*str)
797 {
798 case 'a':
799 attr |= SHF_ALLOC;
800 break;
801 case 'e':
802 attr |= SHF_EXCLUDE;
803 break;
804 case 'w':
805 attr |= SHF_WRITE;
806 break;
807 case 'x':
808 attr |= SHF_EXECINSTR;
809 break;
810 case 'M':
811 attr |= SHF_MERGE;
812 break;
813 case 'S':
814 attr |= SHF_STRINGS;
815 break;
816 case 'G':
817 attr |= SHF_GROUP;
818 break;
819 case 'T':
820 attr |= SHF_TLS;
821 break;
822 case 'd':
823 *gnu_attr |= SHF_GNU_MBIND;
824 break;
825 case '?':
826 *is_clone = TRUE;
827 break;
828 /* Compatibility. */
829 case 'm':
830 if (*(str - 1) == 'a')
831 {
832 attr |= SHF_MERGE;
833 if (len > 1 && str[1] == 's')
834 {
835 attr |= SHF_STRINGS;
836 str++, len--;
837 }
838 break;
839 }
840 /* Fall through. */
841 default:
842 {
843 const char *bad_msg = _("unrecognized .section attribute:"
844 " want a,e,w,x,M,S,G,T or number");
845 #ifdef md_elf_section_letter
846 bfd_vma md_attr = md_elf_section_letter (*str, &bad_msg);
847 if (md_attr != (bfd_vma) -1)
848 attr |= md_attr;
849 else
850 #endif
851 if (ISDIGIT (*str))
852 {
853 char * end;
854
855 attr |= strtoul (str, & end, 0);
856 /* Update str and len, allowing for the fact that
857 we will execute str++ and len-- below. */
858 end --;
859 len -= (end - str);
860 str = end;
861 }
862 else
863 as_fatal ("%s", bad_msg);
864 }
865 break;
866 }
867 str++, len--;
868 }
869
870 return attr;
871 }
872
873 static int
874 obj_elf_section_type (char *str, size_t len, bfd_boolean warn)
875 {
876 if (len == 8 && strncmp (str, "progbits", 8) == 0)
877 return SHT_PROGBITS;
878 if (len == 6 && strncmp (str, "nobits", 6) == 0)
879 return SHT_NOBITS;
880 if (len == 4 && strncmp (str, "note", 4) == 0)
881 return SHT_NOTE;
882 if (len == 10 && strncmp (str, "init_array", 10) == 0)
883 return SHT_INIT_ARRAY;
884 if (len == 10 && strncmp (str, "fini_array", 10) == 0)
885 return SHT_FINI_ARRAY;
886 if (len == 13 && strncmp (str, "preinit_array", 13) == 0)
887 return SHT_PREINIT_ARRAY;
888
889 #ifdef md_elf_section_type
890 {
891 int md_type = md_elf_section_type (str, len);
892 if (md_type >= 0)
893 return md_type;
894 }
895 #endif
896
897 if (ISDIGIT (*str))
898 {
899 char * end;
900 int type = strtoul (str, & end, 0);
901
902 if (warn && (size_t) (end - str) != len)
903 as_warn (_("extraneous characters at end of numeric section type"));
904
905 return type;
906 }
907
908 if (warn)
909 as_warn (_("unrecognized section type"));
910 return 0;
911 }
912
913 static bfd_vma
914 obj_elf_section_word (char *str, size_t len, int *type)
915 {
916 int ret;
917
918 if (len == 5 && strncmp (str, "write", 5) == 0)
919 return SHF_WRITE;
920 if (len == 5 && strncmp (str, "alloc", 5) == 0)
921 return SHF_ALLOC;
922 if (len == 9 && strncmp (str, "execinstr", 9) == 0)
923 return SHF_EXECINSTR;
924 if (len == 7 && strncmp (str, "exclude", 7) == 0)
925 return SHF_EXCLUDE;
926 if (len == 3 && strncmp (str, "tls", 3) == 0)
927 return SHF_TLS;
928
929 #ifdef md_elf_section_word
930 {
931 bfd_vma md_attr = md_elf_section_word (str, len);
932 if (md_attr > 0)
933 return md_attr;
934 }
935 #endif
936
937 ret = obj_elf_section_type (str, len, FALSE);
938 if (ret != 0)
939 *type = ret;
940 else
941 as_warn (_("unrecognized section attribute"));
942
943 return 0;
944 }
945
946 /* Get name of section. */
947 const char *
948 obj_elf_section_name (void)
949 {
950 char *name;
951
952 SKIP_WHITESPACE ();
953 if (*input_line_pointer == '"')
954 {
955 int dummy;
956
957 name = demand_copy_C_string (&dummy);
958 if (name == NULL)
959 {
960 ignore_rest_of_line ();
961 return NULL;
962 }
963 }
964 else
965 {
966 char *end = input_line_pointer;
967
968 while (0 == strchr ("\n\t,; ", *end))
969 end++;
970 if (end == input_line_pointer)
971 {
972 as_bad (_("missing name"));
973 ignore_rest_of_line ();
974 return NULL;
975 }
976
977 name = xmemdup0 (input_line_pointer, end - input_line_pointer);
978
979 while (flag_sectname_subst)
980 {
981 char *subst = strchr (name, '%');
982 if (subst && subst[1] == 'S')
983 {
984 int oldlen = strlen (name);
985 int substlen = strlen (now_seg->name);
986 int newlen = oldlen - 2 + substlen;
987 char *newname = XNEWVEC (char, newlen + 1);
988 int headlen = subst - name;
989 memcpy (newname, name, headlen);
990 strcpy (newname + headlen, now_seg->name);
991 strcat (newname + headlen, subst + 2);
992 xfree (name);
993 name = newname;
994 }
995 else
996 break;
997 }
998
999 #ifdef tc_canonicalize_section_name
1000 name = tc_canonicalize_section_name (name);
1001 #endif
1002 input_line_pointer = end;
1003 }
1004 SKIP_WHITESPACE ();
1005 return name;
1006 }
1007
1008 void
1009 obj_elf_section (int push)
1010 {
1011 const char *name;
1012 char *beg;
1013 int type, dummy;
1014 bfd_vma attr;
1015 bfd_vma gnu_attr;
1016 int entsize;
1017 int linkonce;
1018 subsegT new_subsection = -1;
1019 struct elf_section_match match;
1020
1021 if (flag_mri)
1022 {
1023 char mri_type;
1024
1025 #ifdef md_flush_pending_output
1026 md_flush_pending_output ();
1027 #endif
1028
1029 previous_section = now_seg;
1030 previous_subsection = now_subseg;
1031
1032 s_mri_sect (&mri_type);
1033
1034 #ifdef md_elf_section_change_hook
1035 md_elf_section_change_hook ();
1036 #endif
1037
1038 return;
1039 }
1040
1041 name = obj_elf_section_name ();
1042 if (name == NULL)
1043 return;
1044
1045 memset (&match, 0, sizeof (match));
1046
1047 symbolS * sym;
1048 if ((sym = symbol_find (name)) != NULL
1049 && ! symbol_section_p (sym)
1050 && S_IS_DEFINED (sym)
1051 && ! S_IS_VOLATILE (sym)
1052 && ! S_CAN_BE_REDEFINED (sym))
1053 {
1054 as_bad (_("section name '%s' already defined as another symbol"), name);
1055 ignore_rest_of_line ();
1056 return;
1057 }
1058 type = SHT_NULL;
1059 attr = 0;
1060 gnu_attr = 0;
1061 entsize = 0;
1062 linkonce = 0;
1063
1064 if (*input_line_pointer == ',')
1065 {
1066 /* Skip the comma. */
1067 ++input_line_pointer;
1068 SKIP_WHITESPACE ();
1069
1070 if (push && ISDIGIT (*input_line_pointer))
1071 {
1072 /* .pushsection has an optional subsection. */
1073 new_subsection = (subsegT) get_absolute_expression ();
1074
1075 SKIP_WHITESPACE ();
1076
1077 /* Stop if we don't see a comma. */
1078 if (*input_line_pointer != ',')
1079 goto done;
1080
1081 /* Skip the comma. */
1082 ++input_line_pointer;
1083 SKIP_WHITESPACE ();
1084 }
1085
1086 if (*input_line_pointer == '"')
1087 {
1088 bfd_boolean is_clone;
1089
1090 beg = demand_copy_C_string (&dummy);
1091 if (beg == NULL)
1092 {
1093 ignore_rest_of_line ();
1094 return;
1095 }
1096 attr |= obj_elf_parse_section_letters (beg, strlen (beg),
1097 &is_clone, &gnu_attr);
1098
1099 SKIP_WHITESPACE ();
1100 if (*input_line_pointer == ',')
1101 {
1102 char c;
1103 char *save = input_line_pointer;
1104
1105 ++input_line_pointer;
1106 SKIP_WHITESPACE ();
1107 c = *input_line_pointer;
1108 if (c == '"')
1109 {
1110 beg = demand_copy_C_string (&dummy);
1111 if (beg == NULL)
1112 {
1113 ignore_rest_of_line ();
1114 return;
1115 }
1116 type = obj_elf_section_type (beg, strlen (beg), TRUE);
1117 }
1118 else if (c == '@' || c == '%')
1119 {
1120 ++input_line_pointer;
1121
1122 if (ISDIGIT (* input_line_pointer))
1123 type = strtoul (input_line_pointer, &input_line_pointer, 0);
1124 else
1125 {
1126 c = get_symbol_name (& beg);
1127 (void) restore_line_pointer (c);
1128 type = obj_elf_section_type (beg,
1129 input_line_pointer - beg,
1130 TRUE);
1131 }
1132 }
1133 else
1134 input_line_pointer = save;
1135 }
1136
1137 SKIP_WHITESPACE ();
1138 if ((attr & SHF_MERGE) != 0 && *input_line_pointer == ',')
1139 {
1140 ++input_line_pointer;
1141 SKIP_WHITESPACE ();
1142 entsize = get_absolute_expression ();
1143 SKIP_WHITESPACE ();
1144 if (entsize < 0)
1145 {
1146 as_warn (_("invalid merge entity size"));
1147 attr &= ~SHF_MERGE;
1148 entsize = 0;
1149 }
1150 }
1151 else if ((attr & SHF_MERGE) != 0)
1152 {
1153 as_warn (_("entity size for SHF_MERGE not specified"));
1154 attr &= ~SHF_MERGE;
1155 }
1156
1157 if ((attr & SHF_GROUP) != 0 && is_clone)
1158 {
1159 as_warn (_("? section flag ignored with G present"));
1160 is_clone = FALSE;
1161 }
1162 if ((attr & SHF_GROUP) != 0 && *input_line_pointer == ',')
1163 {
1164 ++input_line_pointer;
1165 match.group_name = obj_elf_section_name ();
1166 if (match.group_name == NULL)
1167 attr &= ~SHF_GROUP;
1168 else if (*input_line_pointer == ',')
1169 {
1170 ++input_line_pointer;
1171 SKIP_WHITESPACE ();
1172 if (strncmp (input_line_pointer, "comdat", 6) == 0)
1173 {
1174 input_line_pointer += 6;
1175 linkonce = 1;
1176 }
1177 }
1178 else if (strncmp (name, ".gnu.linkonce", 13) == 0)
1179 linkonce = 1;
1180 }
1181 else if ((attr & SHF_GROUP) != 0)
1182 {
1183 as_warn (_("group name for SHF_GROUP not specified"));
1184 attr &= ~SHF_GROUP;
1185 }
1186
1187 if (is_clone)
1188 {
1189 const char *now_group = elf_group_name (now_seg);
1190 if (now_group != NULL)
1191 {
1192 match.group_name = xstrdup (now_group);
1193 linkonce = (now_seg->flags & SEC_LINK_ONCE) != 0;
1194 }
1195 }
1196
1197 if ((gnu_attr & SHF_GNU_MBIND) != 0 && *input_line_pointer == ',')
1198 {
1199 char *save = input_line_pointer;
1200 ++input_line_pointer;
1201 SKIP_WHITESPACE ();
1202 if (ISDIGIT (* input_line_pointer))
1203 {
1204 char *t = input_line_pointer;
1205 match.info = strtoul (input_line_pointer,
1206 &input_line_pointer, 0);
1207 if (match.info == (unsigned int) -1)
1208 {
1209 as_warn (_("unsupported mbind section info: %s"), t);
1210 match.info = 0;
1211 }
1212 }
1213 else
1214 input_line_pointer = save;
1215 }
1216
1217 if (*input_line_pointer == ',')
1218 {
1219 char *save = input_line_pointer;
1220 ++input_line_pointer;
1221 SKIP_WHITESPACE ();
1222 if (strncmp (input_line_pointer, "unique", 6) == 0)
1223 {
1224 input_line_pointer += 6;
1225 SKIP_WHITESPACE ();
1226 if (*input_line_pointer == ',')
1227 {
1228 ++input_line_pointer;
1229 SKIP_WHITESPACE ();
1230 if (ISDIGIT (* input_line_pointer))
1231 {
1232 bfd_vma id;
1233 bfd_boolean overflow;
1234 char *t = input_line_pointer;
1235 if (sizeof (bfd_vma) <= sizeof (unsigned long))
1236 {
1237 errno = 0;
1238 id = strtoul (input_line_pointer,
1239 &input_line_pointer, 0);
1240 overflow = (id == (unsigned long) -1
1241 && errno == ERANGE);
1242 }
1243 else
1244 {
1245 id = bfd_scan_vma
1246 (input_line_pointer,
1247 (const char **) &input_line_pointer, 0);
1248 overflow = id == ~(bfd_vma) 0;
1249 }
1250 if (overflow || id > (unsigned int) -1)
1251 {
1252 char *linefeed, saved_char = 0;
1253 if ((linefeed = strchr (t, '\n')) != NULL)
1254 {
1255 saved_char = *linefeed;
1256 *linefeed = '\0';
1257 }
1258 as_bad (_("unsupported section id: %s"), t);
1259 if (saved_char)
1260 *linefeed = saved_char;
1261 }
1262 else
1263 {
1264 match.section_id = id;
1265 match.flags |= SEC_ASSEMBLER_SECTION_ID;
1266 }
1267 }
1268 }
1269 }
1270 else
1271 input_line_pointer = save;
1272 }
1273 }
1274 else
1275 {
1276 do
1277 {
1278 char c;
1279
1280 SKIP_WHITESPACE ();
1281 if (*input_line_pointer != '#')
1282 {
1283 as_bad (_("character following name is not '#'"));
1284 ignore_rest_of_line ();
1285 return;
1286 }
1287 ++input_line_pointer;
1288 c = get_symbol_name (& beg);
1289 (void) restore_line_pointer (c);
1290
1291 attr |= obj_elf_section_word (beg, input_line_pointer - beg,
1292 &type);
1293
1294 SKIP_WHITESPACE ();
1295 }
1296 while (*input_line_pointer++ == ',');
1297 --input_line_pointer;
1298 }
1299 }
1300
1301 done:
1302 demand_empty_rest_of_line ();
1303
1304 obj_elf_change_section (name, type, attr, entsize, &match, linkonce,
1305 push);
1306
1307 if ((gnu_attr & SHF_GNU_MBIND) != 0)
1308 {
1309 struct elf_backend_data *bed;
1310
1311 if ((attr & SHF_ALLOC) == 0)
1312 as_bad (_("SHF_ALLOC isn't set for GNU_MBIND section: %s"), name);
1313
1314 bed = (struct elf_backend_data *) get_elf_backend_data (stdoutput);
1315 if (bed->elf_osabi == ELFOSABI_NONE)
1316 bed->elf_osabi = ELFOSABI_GNU;
1317 else if (bed->elf_osabi != ELFOSABI_GNU
1318 && bed->elf_osabi != ELFOSABI_FREEBSD)
1319 as_bad (_("GNU_MBIND section is supported only by GNU "
1320 "and FreeBSD targets"));
1321 elf_tdata (stdoutput)->has_gnu_osabi |= elf_gnu_osabi_mbind;
1322 }
1323 elf_section_flags (now_seg) |= gnu_attr;
1324
1325 if (push && new_subsection != -1)
1326 subseg_set (now_seg, new_subsection);
1327 }
1328
1329 /* Change to the .data section. */
1330
1331 void
1332 obj_elf_data (int i)
1333 {
1334 #ifdef md_flush_pending_output
1335 md_flush_pending_output ();
1336 #endif
1337
1338 previous_section = now_seg;
1339 previous_subsection = now_subseg;
1340 s_data (i);
1341
1342 #ifdef md_elf_section_change_hook
1343 md_elf_section_change_hook ();
1344 #endif
1345 }
1346
1347 /* Change to the .text section. */
1348
1349 void
1350 obj_elf_text (int i)
1351 {
1352 #ifdef md_flush_pending_output
1353 md_flush_pending_output ();
1354 #endif
1355
1356 previous_section = now_seg;
1357 previous_subsection = now_subseg;
1358 s_text (i);
1359
1360 #ifdef md_elf_section_change_hook
1361 md_elf_section_change_hook ();
1362 #endif
1363 }
1364
1365 /* Change to the *ABS* section. */
1366
1367 void
1368 obj_elf_struct (int i)
1369 {
1370 #ifdef md_flush_pending_output
1371 md_flush_pending_output ();
1372 #endif
1373
1374 previous_section = now_seg;
1375 previous_subsection = now_subseg;
1376 s_struct (i);
1377
1378 #ifdef md_elf_section_change_hook
1379 md_elf_section_change_hook ();
1380 #endif
1381 }
1382
1383 static void
1384 obj_elf_subsection (int ignore ATTRIBUTE_UNUSED)
1385 {
1386 int temp;
1387
1388 #ifdef md_flush_pending_output
1389 md_flush_pending_output ();
1390 #endif
1391
1392 previous_section = now_seg;
1393 previous_subsection = now_subseg;
1394
1395 temp = get_absolute_expression ();
1396 subseg_set (now_seg, (subsegT) temp);
1397 demand_empty_rest_of_line ();
1398
1399 #ifdef md_elf_section_change_hook
1400 md_elf_section_change_hook ();
1401 #endif
1402 }
1403
1404 /* This can be called from the processor backends if they change
1405 sections. */
1406
1407 void
1408 obj_elf_section_change_hook (void)
1409 {
1410 previous_section = now_seg;
1411 previous_subsection = now_subseg;
1412 }
1413
1414 void
1415 obj_elf_previous (int ignore ATTRIBUTE_UNUSED)
1416 {
1417 segT new_section;
1418 int new_subsection;
1419
1420 if (previous_section == 0)
1421 {
1422 as_warn (_(".previous without corresponding .section; ignored"));
1423 return;
1424 }
1425
1426 #ifdef md_flush_pending_output
1427 md_flush_pending_output ();
1428 #endif
1429
1430 new_section = previous_section;
1431 new_subsection = previous_subsection;
1432 previous_section = now_seg;
1433 previous_subsection = now_subseg;
1434 subseg_set (new_section, new_subsection);
1435
1436 #ifdef md_elf_section_change_hook
1437 md_elf_section_change_hook ();
1438 #endif
1439 }
1440
1441 static void
1442 obj_elf_popsection (int xxx ATTRIBUTE_UNUSED)
1443 {
1444 struct section_stack *top = section_stack;
1445
1446 if (top == NULL)
1447 {
1448 as_warn (_(".popsection without corresponding .pushsection; ignored"));
1449 return;
1450 }
1451
1452 #ifdef md_flush_pending_output
1453 md_flush_pending_output ();
1454 #endif
1455
1456 section_stack = top->next;
1457 previous_section = top->prev_seg;
1458 previous_subsection = top->prev_subseg;
1459 subseg_set (top->seg, top->subseg);
1460 free (top);
1461
1462 #ifdef md_elf_section_change_hook
1463 md_elf_section_change_hook ();
1464 #endif
1465 }
1466
1467 static void
1468 obj_elf_line (int ignore ATTRIBUTE_UNUSED)
1469 {
1470 /* Assume delimiter is part of expression. BSD4.2 as fails with
1471 delightful bug, so we are not being incompatible here. */
1472 new_logical_line (NULL, get_absolute_expression ());
1473 demand_empty_rest_of_line ();
1474 }
1475
1476 /* This handles the .symver pseudo-op, which is used to specify a
1477 symbol version. The syntax is ``.symver NAME,SYMVERNAME''.
1478 SYMVERNAME may contain ELF_VER_CHR ('@') characters. This
1479 pseudo-op causes the assembler to emit a symbol named SYMVERNAME
1480 with the same value as the symbol NAME. */
1481
1482 static void
1483 obj_elf_symver (int ignore ATTRIBUTE_UNUSED)
1484 {
1485 char *name;
1486 char c;
1487 char old_lexat;
1488 symbolS *sym;
1489
1490 sym = get_sym_from_input_line_and_check ();
1491
1492 if (*input_line_pointer != ',')
1493 {
1494 as_bad (_("expected comma after name in .symver"));
1495 ignore_rest_of_line ();
1496 return;
1497 }
1498
1499 ++input_line_pointer;
1500 SKIP_WHITESPACE ();
1501
1502 /* Temporarily include '@' in symbol names. */
1503 old_lexat = lex_type[(unsigned char) '@'];
1504 lex_type[(unsigned char) '@'] |= LEX_NAME;
1505 c = get_symbol_name (& name);
1506 lex_type[(unsigned char) '@'] = old_lexat;
1507
1508 if (S_IS_COMMON (sym))
1509 {
1510 as_bad (_("`%s' can't be versioned to common symbol '%s'"),
1511 name, S_GET_NAME (sym));
1512 ignore_rest_of_line ();
1513 return;
1514 }
1515
1516 if (symbol_get_obj (sym)->versioned_name == NULL)
1517 {
1518 symbol_get_obj (sym)->versioned_name = xstrdup (name);
1519
1520 (void) restore_line_pointer (c);
1521
1522 if (strchr (symbol_get_obj (sym)->versioned_name,
1523 ELF_VER_CHR) == NULL)
1524 {
1525 as_bad (_("missing version name in `%s' for symbol `%s'"),
1526 symbol_get_obj (sym)->versioned_name,
1527 S_GET_NAME (sym));
1528 ignore_rest_of_line ();
1529 return;
1530 }
1531 }
1532 else
1533 {
1534 if (strcmp (symbol_get_obj (sym)->versioned_name, name))
1535 {
1536 as_bad (_("multiple versions [`%s'|`%s'] for symbol `%s'"),
1537 name, symbol_get_obj (sym)->versioned_name,
1538 S_GET_NAME (sym));
1539 ignore_rest_of_line ();
1540 return;
1541 }
1542
1543 (void) restore_line_pointer (c);
1544 }
1545
1546 demand_empty_rest_of_line ();
1547 }
1548
1549 /* This handles the .vtable_inherit pseudo-op, which is used to indicate
1550 to the linker the hierarchy in which a particular table resides. The
1551 syntax is ".vtable_inherit CHILDNAME, PARENTNAME". */
1552
1553 struct fix *
1554 obj_elf_get_vtable_inherit (void)
1555 {
1556 char *cname, *pname;
1557 symbolS *csym, *psym;
1558 char c, bad = 0;
1559
1560 if (*input_line_pointer == '#')
1561 ++input_line_pointer;
1562
1563 c = get_symbol_name (& cname);
1564 csym = symbol_find (cname);
1565
1566 /* GCFIXME: should check that we don't have two .vtable_inherits for
1567 the same child symbol. Also, we can currently only do this if the
1568 child symbol is already exists and is placed in a fragment. */
1569
1570 if (csym == NULL || symbol_get_frag (csym) == NULL)
1571 {
1572 as_bad (_("expected `%s' to have already been set for .vtable_inherit"),
1573 cname);
1574 bad = 1;
1575 }
1576
1577 *input_line_pointer = c;
1578
1579 SKIP_WHITESPACE_AFTER_NAME ();
1580 if (*input_line_pointer != ',')
1581 {
1582 as_bad (_("expected comma after name in .vtable_inherit"));
1583 ignore_rest_of_line ();
1584 return NULL;
1585 }
1586
1587 ++input_line_pointer;
1588 SKIP_WHITESPACE ();
1589
1590 if (*input_line_pointer == '#')
1591 ++input_line_pointer;
1592
1593 if (input_line_pointer[0] == '0'
1594 && (input_line_pointer[1] == '\0'
1595 || ISSPACE (input_line_pointer[1])))
1596 {
1597 psym = section_symbol (absolute_section);
1598 ++input_line_pointer;
1599 }
1600 else
1601 {
1602 c = get_symbol_name (& pname);
1603 psym = symbol_find_or_make (pname);
1604 restore_line_pointer (c);
1605 }
1606
1607 demand_empty_rest_of_line ();
1608
1609 if (bad)
1610 return NULL;
1611
1612 gas_assert (symbol_get_value_expression (csym)->X_op == O_constant);
1613 return fix_new (symbol_get_frag (csym),
1614 symbol_get_value_expression (csym)->X_add_number,
1615 0, psym, 0, 0, BFD_RELOC_VTABLE_INHERIT);
1616 }
1617
1618 /* This is a version of obj_elf_get_vtable_inherit() that is
1619 suitable for use in struct _pseudo_type tables. */
1620
1621 void
1622 obj_elf_vtable_inherit (int ignore ATTRIBUTE_UNUSED)
1623 {
1624 (void) obj_elf_get_vtable_inherit ();
1625 }
1626
1627 /* This handles the .vtable_entry pseudo-op, which is used to indicate
1628 to the linker that a vtable slot was used. The syntax is
1629 ".vtable_entry tablename, offset". */
1630
1631 struct fix *
1632 obj_elf_get_vtable_entry (void)
1633 {
1634 symbolS *sym;
1635 offsetT offset;
1636
1637 if (*input_line_pointer == '#')
1638 ++input_line_pointer;
1639
1640 sym = get_sym_from_input_line_and_check ();
1641 if (*input_line_pointer != ',')
1642 {
1643 as_bad (_("expected comma after name in .vtable_entry"));
1644 ignore_rest_of_line ();
1645 return NULL;
1646 }
1647
1648 ++input_line_pointer;
1649 if (*input_line_pointer == '#')
1650 ++input_line_pointer;
1651
1652 offset = get_absolute_expression ();
1653
1654 demand_empty_rest_of_line ();
1655
1656 return fix_new (frag_now, frag_now_fix (), 0, sym, offset, 0,
1657 BFD_RELOC_VTABLE_ENTRY);
1658 }
1659
1660 /* This is a version of obj_elf_get_vtable_entry() that is
1661 suitable for use in struct _pseudo_type tables. */
1662
1663 void
1664 obj_elf_vtable_entry (int ignore ATTRIBUTE_UNUSED)
1665 {
1666 (void) obj_elf_get_vtable_entry ();
1667 }
1668
1669 #define skip_whitespace(str) do { if (*(str) == ' ') ++(str); } while (0)
1670
1671 static inline int
1672 skip_past_char (char ** str, char c)
1673 {
1674 if (**str == c)
1675 {
1676 (*str)++;
1677 return 0;
1678 }
1679 else
1680 return -1;
1681 }
1682 #define skip_past_comma(str) skip_past_char (str, ',')
1683
1684 /* A list of attributes that have been explicitly set by the assembly code.
1685 VENDOR is the vendor id, BASE is the tag shifted right by the number
1686 of bits in MASK, and bit N of MASK is set if tag BASE+N has been set. */
1687 struct recorded_attribute_info {
1688 struct recorded_attribute_info *next;
1689 int vendor;
1690 unsigned int base;
1691 unsigned long mask;
1692 };
1693 static struct recorded_attribute_info *recorded_attributes;
1694
1695 /* Record that we have seen an explicit specification of attribute TAG
1696 for vendor VENDOR. */
1697
1698 static void
1699 record_attribute (int vendor, unsigned int tag)
1700 {
1701 unsigned int base;
1702 unsigned long mask;
1703 struct recorded_attribute_info *rai;
1704
1705 base = tag / (8 * sizeof (rai->mask));
1706 mask = 1UL << (tag % (8 * sizeof (rai->mask)));
1707 for (rai = recorded_attributes; rai; rai = rai->next)
1708 if (rai->vendor == vendor && rai->base == base)
1709 {
1710 rai->mask |= mask;
1711 return;
1712 }
1713
1714 rai = XNEW (struct recorded_attribute_info);
1715 rai->next = recorded_attributes;
1716 rai->vendor = vendor;
1717 rai->base = base;
1718 rai->mask = mask;
1719 recorded_attributes = rai;
1720 }
1721
1722 /* Return true if we have seen an explicit specification of attribute TAG
1723 for vendor VENDOR. */
1724
1725 bfd_boolean
1726 obj_elf_seen_attribute (int vendor, unsigned int tag)
1727 {
1728 unsigned int base;
1729 unsigned long mask;
1730 struct recorded_attribute_info *rai;
1731
1732 base = tag / (8 * sizeof (rai->mask));
1733 mask = 1UL << (tag % (8 * sizeof (rai->mask)));
1734 for (rai = recorded_attributes; rai; rai = rai->next)
1735 if (rai->vendor == vendor && rai->base == base)
1736 return (rai->mask & mask) != 0;
1737 return FALSE;
1738 }
1739
1740 /* Parse an attribute directive for VENDOR.
1741 Returns the attribute number read, or zero on error. */
1742
1743 int
1744 obj_elf_vendor_attribute (int vendor)
1745 {
1746 expressionS exp;
1747 int type;
1748 int tag;
1749 unsigned int i = 0;
1750 char *s = NULL;
1751
1752 /* Read the first number or name. */
1753 skip_whitespace (input_line_pointer);
1754 s = input_line_pointer;
1755 if (ISDIGIT (*input_line_pointer))
1756 {
1757 expression (& exp);
1758 if (exp.X_op != O_constant)
1759 goto bad;
1760 tag = exp.X_add_number;
1761 }
1762 else
1763 {
1764 char *name;
1765
1766 /* A name may contain '_', but no other punctuation. */
1767 for (; ISALNUM (*input_line_pointer) || *input_line_pointer == '_';
1768 ++input_line_pointer)
1769 i++;
1770 if (i == 0)
1771 goto bad;
1772
1773 name = xstrndup (s, i);
1774
1775 #ifndef CONVERT_SYMBOLIC_ATTRIBUTE
1776 #define CONVERT_SYMBOLIC_ATTRIBUTE(a) -1
1777 #endif
1778
1779 tag = CONVERT_SYMBOLIC_ATTRIBUTE (name);
1780 if (tag == -1)
1781 {
1782 as_bad (_("Attribute name not recognised: %s"), name);
1783 ignore_rest_of_line ();
1784 free (name);
1785 return 0;
1786 }
1787 free (name);
1788 }
1789
1790 type = _bfd_elf_obj_attrs_arg_type (stdoutput, vendor, tag);
1791
1792 if (skip_past_comma (&input_line_pointer) == -1)
1793 goto bad;
1794 if (type & 1)
1795 {
1796 expression (& exp);
1797 if (exp.X_op != O_constant)
1798 {
1799 as_bad (_("expected numeric constant"));
1800 ignore_rest_of_line ();
1801 return 0;
1802 }
1803 i = exp.X_add_number;
1804 }
1805 if ((type & 3) == 3
1806 && skip_past_comma (&input_line_pointer) == -1)
1807 {
1808 as_bad (_("expected comma"));
1809 ignore_rest_of_line ();
1810 return 0;
1811 }
1812 if (type & 2)
1813 {
1814 int len;
1815
1816 skip_whitespace (input_line_pointer);
1817 if (*input_line_pointer != '"')
1818 goto bad_string;
1819 s = demand_copy_C_string (&len);
1820 }
1821
1822 record_attribute (vendor, tag);
1823 switch (type & 3)
1824 {
1825 case 3:
1826 bfd_elf_add_obj_attr_int_string (stdoutput, vendor, tag, i, s);
1827 break;
1828 case 2:
1829 bfd_elf_add_obj_attr_string (stdoutput, vendor, tag, s);
1830 break;
1831 case 1:
1832 bfd_elf_add_obj_attr_int (stdoutput, vendor, tag, i);
1833 break;
1834 default:
1835 abort ();
1836 }
1837
1838 demand_empty_rest_of_line ();
1839 return tag;
1840 bad_string:
1841 as_bad (_("bad string constant"));
1842 ignore_rest_of_line ();
1843 return 0;
1844 bad:
1845 as_bad (_("expected <tag> , <value>"));
1846 ignore_rest_of_line ();
1847 return 0;
1848 }
1849
1850 /* Parse a .gnu_attribute directive. */
1851
1852 static void
1853 obj_elf_gnu_attribute (int ignored ATTRIBUTE_UNUSED)
1854 {
1855 obj_elf_vendor_attribute (OBJ_ATTR_GNU);
1856 }
1857
1858 void
1859 elf_obj_read_begin_hook (void)
1860 {
1861 #ifdef NEED_ECOFF_DEBUG
1862 if (ECOFF_DEBUGGING)
1863 ecoff_read_begin_hook ();
1864 #endif
1865 }
1866
1867 void
1868 elf_obj_symbol_new_hook (symbolS *symbolP)
1869 {
1870 struct elf_obj_sy *sy_obj;
1871
1872 sy_obj = symbol_get_obj (symbolP);
1873 sy_obj->size = NULL;
1874 sy_obj->versioned_name = NULL;
1875
1876 #ifdef NEED_ECOFF_DEBUG
1877 if (ECOFF_DEBUGGING)
1878 ecoff_symbol_new_hook (symbolP);
1879 #endif
1880 }
1881
1882 /* When setting one symbol equal to another, by default we probably
1883 want them to have the same "size", whatever it means in the current
1884 context. */
1885
1886 void
1887 elf_copy_symbol_attributes (symbolS *dest, symbolS *src)
1888 {
1889 struct elf_obj_sy *srcelf = symbol_get_obj (src);
1890 struct elf_obj_sy *destelf = symbol_get_obj (dest);
1891 if (srcelf->size)
1892 {
1893 if (destelf->size == NULL)
1894 destelf->size = XNEW (expressionS);
1895 *destelf->size = *srcelf->size;
1896 }
1897 else
1898 {
1899 if (destelf->size != NULL)
1900 free (destelf->size);
1901 destelf->size = NULL;
1902 }
1903 S_SET_SIZE (dest, S_GET_SIZE (src));
1904 /* Don't copy visibility. */
1905 S_SET_OTHER (dest, (ELF_ST_VISIBILITY (S_GET_OTHER (dest))
1906 | (S_GET_OTHER (src) & ~ELF_ST_VISIBILITY (-1))));
1907 }
1908
1909 void
1910 obj_elf_version (int ignore ATTRIBUTE_UNUSED)
1911 {
1912 char *name;
1913 unsigned int c;
1914 char *p;
1915 asection *seg = now_seg;
1916 subsegT subseg = now_subseg;
1917 Elf_Internal_Note i_note;
1918 Elf_External_Note e_note;
1919 asection *note_secp = NULL;
1920
1921 SKIP_WHITESPACE ();
1922 if (*input_line_pointer == '\"')
1923 {
1924 unsigned int len;
1925
1926 ++input_line_pointer; /* -> 1st char of string. */
1927 name = input_line_pointer;
1928
1929 while (is_a_char (c = next_char_of_string ()))
1930 ;
1931 c = *input_line_pointer;
1932 *input_line_pointer = '\0';
1933 *(input_line_pointer - 1) = '\0';
1934 *input_line_pointer = c;
1935
1936 /* Create the .note section. */
1937 note_secp = subseg_new (".note", 0);
1938 bfd_set_section_flags (note_secp, SEC_HAS_CONTENTS | SEC_READONLY);
1939 record_alignment (note_secp, 2);
1940
1941 /* Process the version string. */
1942 len = strlen (name) + 1;
1943
1944 /* PR 3456: Although the name field is padded out to an 4-byte
1945 boundary, the namesz field should not be adjusted. */
1946 i_note.namesz = len;
1947 i_note.descsz = 0; /* No description. */
1948 i_note.type = NT_VERSION;
1949 p = frag_more (sizeof (e_note.namesz));
1950 md_number_to_chars (p, i_note.namesz, sizeof (e_note.namesz));
1951 p = frag_more (sizeof (e_note.descsz));
1952 md_number_to_chars (p, i_note.descsz, sizeof (e_note.descsz));
1953 p = frag_more (sizeof (e_note.type));
1954 md_number_to_chars (p, i_note.type, sizeof (e_note.type));
1955 p = frag_more (len);
1956 memcpy (p, name, len);
1957
1958 frag_align (2, 0, 0);
1959
1960 subseg_set (seg, subseg);
1961 }
1962 else
1963 as_bad (_("expected quoted string"));
1964
1965 demand_empty_rest_of_line ();
1966 }
1967
1968 static void
1969 obj_elf_size (int ignore ATTRIBUTE_UNUSED)
1970 {
1971 char *name;
1972 char c = get_symbol_name (&name);
1973 char *p;
1974 expressionS exp;
1975 symbolS *sym;
1976
1977 p = input_line_pointer;
1978 *p = c;
1979 SKIP_WHITESPACE_AFTER_NAME ();
1980 if (*input_line_pointer != ',')
1981 {
1982 *p = 0;
1983 as_bad (_("expected comma after name `%s' in .size directive"), name);
1984 *p = c;
1985 ignore_rest_of_line ();
1986 return;
1987 }
1988 input_line_pointer++;
1989 expression (&exp);
1990 if (exp.X_op == O_absent)
1991 {
1992 as_bad (_("missing expression in .size directive"));
1993 exp.X_op = O_constant;
1994 exp.X_add_number = 0;
1995 }
1996 *p = 0;
1997 sym = symbol_find_or_make (name);
1998 *p = c;
1999 if (exp.X_op == O_constant)
2000 {
2001 S_SET_SIZE (sym, exp.X_add_number);
2002 if (symbol_get_obj (sym)->size)
2003 {
2004 xfree (symbol_get_obj (sym)->size);
2005 symbol_get_obj (sym)->size = NULL;
2006 }
2007 }
2008 else
2009 {
2010 symbol_get_obj (sym)->size = XNEW (expressionS);
2011 *symbol_get_obj (sym)->size = exp;
2012 }
2013 demand_empty_rest_of_line ();
2014 }
2015
2016 /* Handle the ELF .type pseudo-op. This sets the type of a symbol.
2017 There are six syntaxes:
2018
2019 The first (used on Solaris) is
2020 .type SYM,#function
2021 The second (used on UnixWare) is
2022 .type SYM,@function
2023 The third (reportedly to be used on Irix 6.0) is
2024 .type SYM STT_FUNC
2025 The fourth (used on NetBSD/Arm and Linux/ARM) is
2026 .type SYM,%function
2027 The fifth (used on SVR4/860) is
2028 .type SYM,"function"
2029 The sixth (emitted by recent SunPRO under Solaris) is
2030 .type SYM,[0-9]
2031 where the integer is the STT_* value.
2032 */
2033
2034 static char *
2035 obj_elf_type_name (char *cp)
2036 {
2037 char *p;
2038
2039 p = input_line_pointer;
2040 if (*input_line_pointer >= '0'
2041 && *input_line_pointer <= '9')
2042 {
2043 while (*input_line_pointer >= '0'
2044 && *input_line_pointer <= '9')
2045 ++input_line_pointer;
2046 *cp = *input_line_pointer;
2047 *input_line_pointer = '\0';
2048 }
2049 else
2050 *cp = get_symbol_name (&p);
2051
2052 return p;
2053 }
2054
2055 static void
2056 obj_elf_type (int ignore ATTRIBUTE_UNUSED)
2057 {
2058 char c;
2059 int type;
2060 const char *type_name;
2061 symbolS *sym;
2062 elf_symbol_type *elfsym;
2063
2064 sym = get_sym_from_input_line_and_check ();
2065 c = *input_line_pointer;
2066 elfsym = (elf_symbol_type *) symbol_get_bfdsym (sym);
2067
2068 if (*input_line_pointer == ',')
2069 ++input_line_pointer;
2070
2071 SKIP_WHITESPACE ();
2072 if ( *input_line_pointer == '#'
2073 || *input_line_pointer == '@'
2074 || *input_line_pointer == '"'
2075 || *input_line_pointer == '%')
2076 ++input_line_pointer;
2077
2078 type_name = obj_elf_type_name (& c);
2079
2080 type = 0;
2081 if (strcmp (type_name, "function") == 0
2082 || strcmp (type_name, "2") == 0
2083 || strcmp (type_name, "STT_FUNC") == 0)
2084 type = BSF_FUNCTION;
2085 else if (strcmp (type_name, "object") == 0
2086 || strcmp (type_name, "1") == 0
2087 || strcmp (type_name, "STT_OBJECT") == 0)
2088 type = BSF_OBJECT;
2089 else if (strcmp (type_name, "tls_object") == 0
2090 || strcmp (type_name, "6") == 0
2091 || strcmp (type_name, "STT_TLS") == 0)
2092 type = BSF_OBJECT | BSF_THREAD_LOCAL;
2093 else if (strcmp (type_name, "notype") == 0
2094 || strcmp (type_name, "0") == 0
2095 || strcmp (type_name, "STT_NOTYPE") == 0)
2096 ;
2097 else if (strcmp (type_name, "common") == 0
2098 || strcmp (type_name, "5") == 0
2099 || strcmp (type_name, "STT_COMMON") == 0)
2100 {
2101 type = BSF_OBJECT;
2102
2103 if (! S_IS_COMMON (sym))
2104 {
2105 if (S_IS_VOLATILE (sym))
2106 {
2107 sym = symbol_clone (sym, 1);
2108 S_SET_SEGMENT (sym, bfd_com_section_ptr);
2109 S_SET_VALUE (sym, 0);
2110 S_SET_EXTERNAL (sym);
2111 symbol_set_frag (sym, &zero_address_frag);
2112 S_CLEAR_VOLATILE (sym);
2113 }
2114 else if (S_IS_DEFINED (sym) || symbol_equated_p (sym))
2115 as_bad (_("symbol '%s' is already defined"), S_GET_NAME (sym));
2116 else
2117 {
2118 /* FIXME: Is it safe to just change the section ? */
2119 S_SET_SEGMENT (sym, bfd_com_section_ptr);
2120 S_SET_VALUE (sym, 0);
2121 S_SET_EXTERNAL (sym);
2122 }
2123 }
2124 }
2125 else if (strcmp (type_name, "gnu_indirect_function") == 0
2126 || strcmp (type_name, "10") == 0
2127 || strcmp (type_name, "STT_GNU_IFUNC") == 0)
2128 {
2129 struct elf_backend_data *bed;
2130
2131 bed = (struct elf_backend_data *) get_elf_backend_data (stdoutput);
2132 if (bed->elf_osabi == ELFOSABI_NONE)
2133 bed->elf_osabi = ELFOSABI_GNU;
2134 else if (bed->elf_osabi != ELFOSABI_GNU
2135 && bed->elf_osabi != ELFOSABI_FREEBSD)
2136 as_bad (_("symbol type \"%s\" is supported only by GNU "
2137 "and FreeBSD targets"), type_name);
2138 elf_tdata (stdoutput)->has_gnu_osabi |= elf_gnu_osabi_ifunc;
2139 type = BSF_FUNCTION | BSF_GNU_INDIRECT_FUNCTION;
2140 }
2141 else if (strcmp (type_name, "gnu_unique_object") == 0)
2142 {
2143 struct elf_backend_data *bed;
2144
2145 bed = (struct elf_backend_data *) get_elf_backend_data (stdoutput);
2146 if (bed->elf_osabi == ELFOSABI_NONE)
2147 bed->elf_osabi = ELFOSABI_GNU;
2148 else if (bed->elf_osabi != ELFOSABI_GNU)
2149 as_bad (_("symbol type \"%s\" is supported only by GNU targets"),
2150 type_name);
2151 elf_tdata (stdoutput)->has_gnu_osabi |= elf_gnu_osabi_unique;
2152 type = BSF_OBJECT | BSF_GNU_UNIQUE;
2153 }
2154 #ifdef md_elf_symbol_type
2155 else if ((type = md_elf_symbol_type (type_name, sym, elfsym)) != -1)
2156 ;
2157 #endif
2158 else
2159 as_bad (_("unrecognized symbol type \"%s\""), type_name);
2160
2161 *input_line_pointer = c;
2162
2163 if (*input_line_pointer == '"')
2164 ++input_line_pointer;
2165
2166 #ifdef md_elf_symbol_type_change
2167 if (!md_elf_symbol_type_change (sym, elfsym, type))
2168 #endif
2169 {
2170 flagword mask = BSF_FUNCTION | BSF_OBJECT;
2171
2172 if (type != BSF_FUNCTION)
2173 mask |= BSF_GNU_INDIRECT_FUNCTION;
2174 if (type != BSF_OBJECT)
2175 {
2176 mask |= BSF_GNU_UNIQUE | BSF_THREAD_LOCAL;
2177
2178 if (S_IS_COMMON (sym))
2179 {
2180 as_bad (_("cannot change type of common symbol '%s'"),
2181 S_GET_NAME (sym));
2182 mask = type = 0;
2183 }
2184 }
2185
2186 /* Don't warn when changing to STT_NOTYPE. */
2187 if (type)
2188 {
2189 flagword new = (elfsym->symbol.flags & ~mask) | type;
2190
2191 if (new != (elfsym->symbol.flags | type))
2192 as_warn (_("symbol '%s' already has its type set"), S_GET_NAME (sym));
2193 elfsym->symbol.flags = new;
2194 }
2195 else
2196 elfsym->symbol.flags &= ~mask;
2197 }
2198
2199 demand_empty_rest_of_line ();
2200 }
2201
2202 static void
2203 obj_elf_ident (int ignore ATTRIBUTE_UNUSED)
2204 {
2205 static segT comment_section;
2206 segT old_section = now_seg;
2207 int old_subsection = now_subseg;
2208
2209 #ifdef md_flush_pending_output
2210 md_flush_pending_output ();
2211 #endif
2212
2213 if (!comment_section)
2214 {
2215 char *p;
2216 comment_section = subseg_new (".comment", 0);
2217 bfd_set_section_flags (comment_section, (SEC_READONLY | SEC_HAS_CONTENTS
2218 | SEC_MERGE | SEC_STRINGS));
2219 comment_section->entsize = 1;
2220 #ifdef md_elf_section_change_hook
2221 md_elf_section_change_hook ();
2222 #endif
2223 p = frag_more (1);
2224 *p = 0;
2225 }
2226 else
2227 subseg_set (comment_section, 0);
2228 stringer (8 + 1);
2229 subseg_set (old_section, old_subsection);
2230 }
2231
2232 #ifdef INIT_STAB_SECTION
2233
2234 /* The first entry in a .stabs section is special. */
2235
2236 void
2237 obj_elf_init_stab_section (segT seg)
2238 {
2239 const char *file;
2240 char *p;
2241 char *stabstr_name;
2242 unsigned int stroff;
2243
2244 /* Force the section to align to a longword boundary. Without this,
2245 UnixWare ar crashes. */
2246 bfd_set_section_alignment (seg, 2);
2247
2248 /* Make space for this first symbol. */
2249 p = frag_more (12);
2250 /* Zero it out. */
2251 memset (p, 0, 12);
2252 file = as_where (NULL);
2253 stabstr_name = concat (segment_name (seg), "str", (char *) NULL);
2254 stroff = get_stab_string_offset (file, stabstr_name, TRUE);
2255 know (stroff == 1 || (stroff == 0 && file[0] == '\0'));
2256 md_number_to_chars (p, stroff, 4);
2257 seg_info (seg)->stabu.p = p;
2258 }
2259
2260 #endif
2261
2262 /* Fill in the counts in the first entry in a .stabs section. */
2263
2264 static void
2265 adjust_stab_sections (bfd *abfd, asection *sec, void *xxx ATTRIBUTE_UNUSED)
2266 {
2267 char *name;
2268 asection *strsec;
2269 char *p;
2270 int strsz, nsyms;
2271
2272 if (strncmp (".stab", sec->name, 5))
2273 return;
2274 if (!strcmp ("str", sec->name + strlen (sec->name) - 3))
2275 return;
2276
2277 name = concat (sec->name, "str", NULL);
2278 strsec = bfd_get_section_by_name (abfd, name);
2279 if (strsec)
2280 strsz = bfd_section_size (strsec);
2281 else
2282 strsz = 0;
2283 nsyms = bfd_section_size (sec) / 12 - 1;
2284
2285 p = seg_info (sec)->stabu.p;
2286 gas_assert (p != 0);
2287
2288 bfd_h_put_16 (abfd, nsyms, p + 6);
2289 bfd_h_put_32 (abfd, strsz, p + 8);
2290 free (name);
2291 }
2292
2293 #ifdef NEED_ECOFF_DEBUG
2294
2295 /* This function is called by the ECOFF code. It is supposed to
2296 record the external symbol information so that the backend can
2297 write it out correctly. The ELF backend doesn't actually handle
2298 this at the moment, so we do it ourselves. We save the information
2299 in the symbol. */
2300
2301 #ifdef OBJ_MAYBE_ELF
2302 static
2303 #endif
2304 void
2305 elf_ecoff_set_ext (symbolS *sym, struct ecoff_extr *ext)
2306 {
2307 symbol_get_bfdsym (sym)->udata.p = ext;
2308 }
2309
2310 /* This function is called by bfd_ecoff_debug_externals. It is
2311 supposed to *EXT to the external symbol information, and return
2312 whether the symbol should be used at all. */
2313
2314 static bfd_boolean
2315 elf_get_extr (asymbol *sym, EXTR *ext)
2316 {
2317 if (sym->udata.p == NULL)
2318 return FALSE;
2319 *ext = *(EXTR *) sym->udata.p;
2320 return TRUE;
2321 }
2322
2323 /* This function is called by bfd_ecoff_debug_externals. It has
2324 nothing to do for ELF. */
2325
2326 static void
2327 elf_set_index (asymbol *sym ATTRIBUTE_UNUSED,
2328 bfd_size_type indx ATTRIBUTE_UNUSED)
2329 {
2330 }
2331
2332 #endif /* NEED_ECOFF_DEBUG */
2333
2334 void
2335 elf_frob_symbol (symbolS *symp, int *puntp)
2336 {
2337 struct elf_obj_sy *sy_obj;
2338 expressionS *size;
2339
2340 #ifdef NEED_ECOFF_DEBUG
2341 if (ECOFF_DEBUGGING)
2342 ecoff_frob_symbol (symp);
2343 #endif
2344
2345 sy_obj = symbol_get_obj (symp);
2346
2347 size = sy_obj->size;
2348 if (size != NULL)
2349 {
2350 if (resolve_expression (size)
2351 && size->X_op == O_constant)
2352 S_SET_SIZE (symp, size->X_add_number);
2353 else
2354 {
2355 if (!flag_allow_nonconst_size)
2356 as_bad (_(".size expression for %s "
2357 "does not evaluate to a constant"), S_GET_NAME (symp));
2358 else
2359 as_warn (_(".size expression for %s "
2360 "does not evaluate to a constant"), S_GET_NAME (symp));
2361 }
2362 free (sy_obj->size);
2363 sy_obj->size = NULL;
2364 }
2365
2366 if (sy_obj->versioned_name != NULL)
2367 {
2368 char *p;
2369
2370 p = strchr (sy_obj->versioned_name, ELF_VER_CHR);
2371 if (p == NULL)
2372 /* We will have already reported an error about a missing version. */
2373 *puntp = TRUE;
2374
2375 /* This symbol was given a new name with the .symver directive.
2376
2377 If this is an external reference, just rename the symbol to
2378 include the version string. This will make the relocs be
2379 against the correct versioned symbol.
2380
2381 If this is a definition, add an alias. FIXME: Using an alias
2382 will permit the debugging information to refer to the right
2383 symbol. However, it's not clear whether it is the best
2384 approach. */
2385
2386 else if (! S_IS_DEFINED (symp))
2387 {
2388 /* Verify that the name isn't using the @@ syntax--this is
2389 reserved for definitions of the default version to link
2390 against. */
2391 if (p[1] == ELF_VER_CHR)
2392 {
2393 as_bad (_("invalid attempt to declare external version name"
2394 " as default in symbol `%s'"),
2395 sy_obj->versioned_name);
2396 *puntp = TRUE;
2397 }
2398 S_SET_NAME (symp, sy_obj->versioned_name);
2399 }
2400 else
2401 {
2402 if (p[1] == ELF_VER_CHR && p[2] == ELF_VER_CHR)
2403 {
2404 size_t l;
2405
2406 /* The @@@ syntax is a special case. It renames the
2407 symbol name to versioned_name with one `@' removed. */
2408 l = strlen (&p[3]) + 1;
2409 memmove (&p[2], &p[3], l);
2410 S_SET_NAME (symp, sy_obj->versioned_name);
2411 }
2412 else
2413 {
2414 symbolS *symp2;
2415
2416 /* FIXME: Creating a new symbol here is risky. We're
2417 in the final loop over the symbol table. We can
2418 get away with it only because the symbol goes to
2419 the end of the list, where the loop will still see
2420 it. It would probably be better to do this in
2421 obj_frob_file_before_adjust. */
2422
2423 symp2 = symbol_find_or_make (sy_obj->versioned_name);
2424
2425 /* Now we act as though we saw symp2 = sym. */
2426 if (S_IS_COMMON (symp))
2427 {
2428 as_bad (_("`%s' can't be versioned to common symbol '%s'"),
2429 sy_obj->versioned_name, S_GET_NAME (symp));
2430 *puntp = TRUE;
2431 return;
2432 }
2433
2434 S_SET_SEGMENT (symp2, S_GET_SEGMENT (symp));
2435
2436 /* Subtracting out the frag address here is a hack
2437 because we are in the middle of the final loop. */
2438 S_SET_VALUE (symp2,
2439 (S_GET_VALUE (symp)
2440 - symbol_get_frag (symp)->fr_address));
2441
2442 symbol_set_frag (symp2, symbol_get_frag (symp));
2443
2444 /* This will copy over the size information. */
2445 copy_symbol_attributes (symp2, symp);
2446
2447 S_SET_OTHER (symp2, S_GET_OTHER (symp));
2448
2449 if (S_IS_WEAK (symp))
2450 S_SET_WEAK (symp2);
2451
2452 if (S_IS_EXTERNAL (symp))
2453 S_SET_EXTERNAL (symp2);
2454 }
2455 }
2456 }
2457
2458 /* Double check weak symbols. */
2459 if (S_IS_WEAK (symp))
2460 {
2461 if (S_IS_COMMON (symp))
2462 as_bad (_("symbol `%s' can not be both weak and common"),
2463 S_GET_NAME (symp));
2464 }
2465 }
2466
2467 struct group_list
2468 {
2469 asection **head; /* Section lists. */
2470 unsigned int num_group; /* Number of lists. */
2471 struct hash_control *indexes; /* Maps group name to index in head array. */
2472 };
2473
2474 static struct group_list groups;
2475
2476 /* Called via bfd_map_over_sections. If SEC is a member of a group,
2477 add it to a list of sections belonging to the group. INF is a
2478 pointer to a struct group_list, which is where we store the head of
2479 each list. */
2480
2481 static void
2482 build_group_lists (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *inf)
2483 {
2484 struct group_list *list = (struct group_list *) inf;
2485 const char *group_name = elf_group_name (sec);
2486 unsigned int i;
2487 unsigned int *elem_idx;
2488 unsigned int *idx_ptr;
2489
2490 if (group_name == NULL)
2491 return;
2492
2493 /* If this group already has a list, add the section to the head of
2494 the list. */
2495 elem_idx = (unsigned int *) hash_find (list->indexes, group_name);
2496 if (elem_idx != NULL)
2497 {
2498 elf_next_in_group (sec) = list->head[*elem_idx];
2499 list->head[*elem_idx] = sec;
2500 return;
2501 }
2502
2503 /* New group. Make the arrays bigger in chunks to minimize calls to
2504 realloc. */
2505 i = list->num_group;
2506 if ((i & 127) == 0)
2507 {
2508 unsigned int newsize = i + 128;
2509 list->head = XRESIZEVEC (asection *, list->head, newsize);
2510 }
2511 list->head[i] = sec;
2512 list->num_group += 1;
2513
2514 /* Add index to hash. */
2515 idx_ptr = XNEW (unsigned int);
2516 *idx_ptr = i;
2517 hash_insert (list->indexes, group_name, idx_ptr);
2518 }
2519
2520 static void free_section_idx (const char *key ATTRIBUTE_UNUSED, void *val)
2521 {
2522 free ((unsigned int *) val);
2523 }
2524
2525 /* Create symbols for group signature. */
2526
2527 void
2528 elf_adjust_symtab (void)
2529 {
2530 unsigned int i;
2531
2532 /* Go find section groups. */
2533 groups.num_group = 0;
2534 groups.head = NULL;
2535 groups.indexes = hash_new ();
2536 bfd_map_over_sections (stdoutput, build_group_lists, &groups);
2537
2538 /* Make the SHT_GROUP sections that describe each section group. We
2539 can't set up the section contents here yet, because elf section
2540 indices have yet to be calculated. elf.c:set_group_contents does
2541 the rest of the work. */
2542 for (i = 0; i < groups.num_group; i++)
2543 {
2544 const char *group_name = elf_group_name (groups.head[i]);
2545 const char *sec_name;
2546 asection *s;
2547 flagword flags;
2548 struct symbol *sy;
2549
2550 flags = SEC_READONLY | SEC_HAS_CONTENTS | SEC_IN_MEMORY | SEC_GROUP;
2551 for (s = groups.head[i]; s != NULL; s = elf_next_in_group (s))
2552 if ((s->flags ^ flags) & SEC_LINK_ONCE)
2553 {
2554 flags |= SEC_LINK_ONCE | SEC_LINK_DUPLICATES_DISCARD;
2555 if (s != groups.head[i])
2556 {
2557 as_warn (_("assuming all members of group `%s' are COMDAT"),
2558 group_name);
2559 break;
2560 }
2561 }
2562
2563 sec_name = ".group";
2564 s = subseg_force_new (sec_name, 0);
2565 if (s == NULL
2566 || !bfd_set_section_flags (s, flags)
2567 || !bfd_set_section_alignment (s, 2))
2568 {
2569 as_fatal (_("can't create group: %s"),
2570 bfd_errmsg (bfd_get_error ()));
2571 }
2572 elf_section_type (s) = SHT_GROUP;
2573
2574 /* Pass a pointer to the first section in this group. */
2575 elf_next_in_group (s) = groups.head[i];
2576 elf_sec_group (groups.head[i]) = s;
2577 /* Make sure that the signature symbol for the group has the
2578 name of the group. */
2579 sy = symbol_find_exact (group_name);
2580 if (!sy || !symbol_on_chain (sy, symbol_rootP, symbol_lastP))
2581 {
2582 /* Create the symbol now. */
2583 sy = symbol_new (group_name, now_seg, (valueT) 0, frag_now);
2584 #ifdef TE_SOLARIS
2585 /* Before Solaris 11 build 154, Sun ld rejects local group
2586 signature symbols, so make them weak hidden instead. */
2587 symbol_get_bfdsym (sy)->flags |= BSF_WEAK;
2588 S_SET_OTHER (sy, STV_HIDDEN);
2589 #else
2590 symbol_get_obj (sy)->local = 1;
2591 #endif
2592 symbol_table_insert (sy);
2593 }
2594 elf_group_id (s) = symbol_get_bfdsym (sy);
2595 }
2596 }
2597
2598 void
2599 elf_frob_file (void)
2600 {
2601 bfd_map_over_sections (stdoutput, adjust_stab_sections, NULL);
2602
2603 #ifdef elf_tc_final_processing
2604 elf_tc_final_processing ();
2605 #endif
2606 }
2607
2608 /* It removes any unneeded versioned symbols from the symbol table. */
2609
2610 void
2611 elf_frob_file_before_adjust (void)
2612 {
2613 if (symbol_rootP)
2614 {
2615 symbolS *symp;
2616
2617 for (symp = symbol_rootP; symp; symp = symbol_next (symp))
2618 if (!S_IS_DEFINED (symp))
2619 {
2620 if (symbol_get_obj (symp)->versioned_name)
2621 {
2622 char *p;
2623
2624 /* The @@@ syntax is a special case. If the symbol is
2625 not defined, 2 `@'s will be removed from the
2626 versioned_name. */
2627
2628 p = strchr (symbol_get_obj (symp)->versioned_name,
2629 ELF_VER_CHR);
2630 if (p != NULL && p[1] == ELF_VER_CHR && p[2] == ELF_VER_CHR)
2631 {
2632 size_t l = strlen (&p[3]) + 1;
2633 memmove (&p[1], &p[3], l);
2634 }
2635 if (symbol_used_p (symp) == 0
2636 && symbol_used_in_reloc_p (symp) == 0)
2637 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2638 }
2639
2640 /* If there was .weak foo, but foo was neither defined nor
2641 used anywhere, remove it. */
2642
2643 else if (S_IS_WEAK (symp)
2644 && symbol_used_p (symp) == 0
2645 && symbol_used_in_reloc_p (symp) == 0)
2646 symbol_remove (symp, &symbol_rootP, &symbol_lastP);
2647 }
2648 }
2649 }
2650
2651 /* It is required that we let write_relocs have the opportunity to
2652 optimize away fixups before output has begun, since it is possible
2653 to eliminate all fixups for a section and thus we never should
2654 have generated the relocation section. */
2655
2656 void
2657 elf_frob_file_after_relocs (void)
2658 {
2659 unsigned int i;
2660
2661 /* Set SHT_GROUP section size. */
2662 for (i = 0; i < groups.num_group; i++)
2663 {
2664 asection *s, *head, *group;
2665 bfd_size_type size;
2666
2667 head = groups.head[i];
2668 size = 4;
2669 for (s = head; s != NULL; s = elf_next_in_group (s))
2670 size += (s->flags & SEC_RELOC) != 0 ? 8 : 4;
2671
2672 group = elf_sec_group (head);
2673 subseg_set (group, 0);
2674 bfd_set_section_size (group, size);
2675 group->contents = (unsigned char *) frag_more (size);
2676 frag_now->fr_fix = frag_now_fix_octets ();
2677 frag_wane (frag_now);
2678 }
2679
2680 /* Cleanup hash. */
2681 hash_traverse (groups.indexes, free_section_idx);
2682 hash_die (groups.indexes);
2683
2684 #ifdef NEED_ECOFF_DEBUG
2685 if (ECOFF_DEBUGGING)
2686 /* Generate the ECOFF debugging information. */
2687 {
2688 const struct ecoff_debug_swap *debug_swap;
2689 struct ecoff_debug_info debug;
2690 char *buf;
2691 asection *sec;
2692
2693 debug_swap
2694 = get_elf_backend_data (stdoutput)->elf_backend_ecoff_debug_swap;
2695 know (debug_swap != NULL);
2696 ecoff_build_debug (&debug.symbolic_header, &buf, debug_swap);
2697
2698 /* Set up the pointers in debug. */
2699 #define SET(ptr, offset, type) \
2700 debug.ptr = (type) (buf + debug.symbolic_header.offset)
2701
2702 SET (line, cbLineOffset, unsigned char *);
2703 SET (external_dnr, cbDnOffset, void *);
2704 SET (external_pdr, cbPdOffset, void *);
2705 SET (external_sym, cbSymOffset, void *);
2706 SET (external_opt, cbOptOffset, void *);
2707 SET (external_aux, cbAuxOffset, union aux_ext *);
2708 SET (ss, cbSsOffset, char *);
2709 SET (external_fdr, cbFdOffset, void *);
2710 SET (external_rfd, cbRfdOffset, void *);
2711 /* ssext and external_ext are set up just below. */
2712
2713 #undef SET
2714
2715 /* Set up the external symbols. */
2716 debug.ssext = debug.ssext_end = NULL;
2717 debug.external_ext = debug.external_ext_end = NULL;
2718 if (! bfd_ecoff_debug_externals (stdoutput, &debug, debug_swap, TRUE,
2719 elf_get_extr, elf_set_index))
2720 as_fatal (_("failed to set up debugging information: %s"),
2721 bfd_errmsg (bfd_get_error ()));
2722
2723 sec = bfd_get_section_by_name (stdoutput, ".mdebug");
2724 gas_assert (sec != NULL);
2725
2726 know (!stdoutput->output_has_begun);
2727
2728 /* We set the size of the section, call bfd_set_section_contents
2729 to force the ELF backend to allocate a file position, and then
2730 write out the data. FIXME: Is this really the best way to do
2731 this? */
2732 bfd_set_section_size (sec, bfd_ecoff_debug_size (stdoutput, &debug,
2733 debug_swap));
2734
2735 /* Pass BUF to bfd_set_section_contents because this will
2736 eventually become a call to fwrite, and ISO C prohibits
2737 passing a NULL pointer to a stdio function even if the
2738 pointer will not be used. */
2739 if (! bfd_set_section_contents (stdoutput, sec, buf, 0, 0))
2740 as_fatal (_("can't start writing .mdebug section: %s"),
2741 bfd_errmsg (bfd_get_error ()));
2742
2743 know (stdoutput->output_has_begun);
2744 know (sec->filepos != 0);
2745
2746 if (! bfd_ecoff_write_debug (stdoutput, &debug, debug_swap,
2747 sec->filepos))
2748 as_fatal (_("could not write .mdebug section: %s"),
2749 bfd_errmsg (bfd_get_error ()));
2750 }
2751 #endif /* NEED_ECOFF_DEBUG */
2752 }
2753
2754 static void
2755 elf_generate_asm_lineno (void)
2756 {
2757 #ifdef NEED_ECOFF_DEBUG
2758 if (ECOFF_DEBUGGING)
2759 ecoff_generate_asm_lineno ();
2760 #endif
2761 }
2762
2763 static void
2764 elf_process_stab (segT sec ATTRIBUTE_UNUSED,
2765 int what ATTRIBUTE_UNUSED,
2766 const char *string ATTRIBUTE_UNUSED,
2767 int type ATTRIBUTE_UNUSED,
2768 int other ATTRIBUTE_UNUSED,
2769 int desc ATTRIBUTE_UNUSED)
2770 {
2771 #ifdef NEED_ECOFF_DEBUG
2772 if (ECOFF_DEBUGGING)
2773 ecoff_stab (sec, what, string, type, other, desc);
2774 #endif
2775 }
2776
2777 static int
2778 elf_separate_stab_sections (void)
2779 {
2780 #ifdef NEED_ECOFF_DEBUG
2781 return (!ECOFF_DEBUGGING);
2782 #else
2783 return 1;
2784 #endif
2785 }
2786
2787 static void
2788 elf_init_stab_section (segT seg)
2789 {
2790 #ifdef NEED_ECOFF_DEBUG
2791 if (!ECOFF_DEBUGGING)
2792 #endif
2793 obj_elf_init_stab_section (seg);
2794 }
2795
2796 const struct format_ops elf_format_ops =
2797 {
2798 bfd_target_elf_flavour,
2799 0, /* dfl_leading_underscore */
2800 1, /* emit_section_symbols */
2801 elf_begin,
2802 elf_file_symbol,
2803 elf_frob_symbol,
2804 elf_frob_file,
2805 elf_frob_file_before_adjust,
2806 0, /* obj_frob_file_before_fix */
2807 elf_frob_file_after_relocs,
2808 elf_s_get_size, elf_s_set_size,
2809 elf_s_get_align, elf_s_set_align,
2810 elf_s_get_other,
2811 elf_s_set_other,
2812 0, /* s_get_desc */
2813 0, /* s_set_desc */
2814 0, /* s_get_type */
2815 0, /* s_set_type */
2816 elf_copy_symbol_attributes,
2817 elf_generate_asm_lineno,
2818 elf_process_stab,
2819 elf_separate_stab_sections,
2820 elf_init_stab_section,
2821 elf_sec_sym_ok_for_reloc,
2822 elf_pop_insert,
2823 #ifdef NEED_ECOFF_DEBUG
2824 elf_ecoff_set_ext,
2825 #else
2826 0, /* ecoff_set_ext */
2827 #endif
2828 elf_obj_read_begin_hook,
2829 elf_obj_symbol_new_hook,
2830 0,
2831 elf_adjust_symtab
2832 };
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