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elfread.c
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1/* Read ELF (Executable and Linking Format) object files for GDB.
2
3 Copyright (C) 1991-2023 Free Software Foundation, Inc.
4
5 Written by Fred Fish at Cygnus Support.
6
7 This file is part of GDB.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21
22#include "defs.h"
23#include "bfd.h"
24#include "elf-bfd.h"
25#include "elf/common.h"
26#include "elf/internal.h"
27#include "elf/mips.h"
28#include "symtab.h"
29#include "symfile.h"
30#include "objfiles.h"
31#include "stabsread.h"
32#include "demangle.h"
33#include "filenames.h"
34#include "probe.h"
35#include "arch-utils.h"
36#include "gdbtypes.h"
37#include "value.h"
38#include "infcall.h"
39#include "gdbthread.h"
40#include "inferior.h"
41#include "regcache.h"
42#include "bcache.h"
43#include "gdb_bfd.h"
44#include "build-id.h"
45#include "location.h"
46#include "auxv.h"
47#include "mdebugread.h"
48#include "ctfread.h"
49#include "gdbsupport/gdb_string_view.h"
50#include "gdbsupport/scoped_fd.h"
51#include "debuginfod-support.h"
52#include "dwarf2/public.h"
53#include "cli/cli-cmds.h"
54
55/* Whether ctf should always be read, or only if no dwarf is present. */
56static bool always_read_ctf;
57
58/* The struct elfinfo is available only during ELF symbol table and
59 psymtab reading. It is destroyed at the completion of psymtab-reading.
60 It's local to elf_symfile_read. */
61
62struct elfinfo
63 {
64 asection *stabsect; /* Section pointer for .stab section */
65 asection *mdebugsect; /* Section pointer for .mdebug section */
66 asection *ctfsect; /* Section pointer for .ctf section */
67 };
68
69/* Type for per-BFD data. */
70
71typedef std::vector<std::unique_ptr<probe>> elfread_data;
72
73/* Per-BFD data for probe info. */
74
76
77/* Minimal symbols located at the GOT entries for .plt - that is the real
78 pointer where the given entry will jump to. It gets updated by the real
79 function address during lazy ld.so resolving in the inferior. These
80 minimal symbols are indexed for <tab>-completion. */
81
82#define SYMBOL_GOT_PLT_SUFFIX "@got.plt"
83
84/* Locate the segments in ABFD. */
85
88{
89 Elf_Internal_Phdr *phdrs, **segments;
90 long phdrs_size;
91 int num_phdrs, num_segments, num_sections, i;
92 asection *sect;
93
94 phdrs_size = bfd_get_elf_phdr_upper_bound (abfd);
95 if (phdrs_size == -1)
96 return NULL;
97
98 phdrs = (Elf_Internal_Phdr *) alloca (phdrs_size);
99 num_phdrs = bfd_get_elf_phdrs (abfd, phdrs);
100 if (num_phdrs == -1)
101 return NULL;
102
103 num_segments = 0;
104 segments = XALLOCAVEC (Elf_Internal_Phdr *, num_phdrs);
105 for (i = 0; i < num_phdrs; i++)
106 if (phdrs[i].p_type == PT_LOAD)
107 segments[num_segments++] = &phdrs[i];
108
109 if (num_segments == 0)
110 return NULL;
111
113 data->segments.reserve (num_segments);
114
115 for (i = 0; i < num_segments; i++)
116 data->segments.emplace_back (segments[i]->p_vaddr, segments[i]->p_memsz);
117
118 num_sections = bfd_count_sections (abfd);
119
120 /* All elements are initialized to 0 (map to no segment). */
121 data->segment_info.resize (num_sections);
122
123 for (i = 0, sect = abfd->sections; sect != NULL; i++, sect = sect->next)
124 {
125 int j;
126
127 if ((bfd_section_flags (sect) & SEC_ALLOC) == 0)
128 continue;
129
130 Elf_Internal_Shdr *this_hdr = &elf_section_data (sect)->this_hdr;
131
132 for (j = 0; j < num_segments; j++)
133 if (ELF_SECTION_IN_SEGMENT (this_hdr, segments[j]))
134 {
135 data->segment_info[i] = j + 1;
136 break;
137 }
138
139 /* We should have found a segment for every non-empty section.
140 If we haven't, we will not relocate this section by any
141 offsets we apply to the segments. As an exception, do not
142 warn about SHT_NOBITS sections; in normal ELF execution
143 environments, SHT_NOBITS means zero-initialized and belongs
144 in a segment, but in no-OS environments some tools (e.g. ARM
145 RealView) use SHT_NOBITS for uninitialized data. Since it is
146 uninitialized, it doesn't need a program header. Such
147 binaries are not relocatable. */
148
149 /* Exclude debuginfo files from this warning, too, since those
150 are often not strictly compliant with the standard. See, e.g.,
151 ld/24717 for more discussion. */
152 if (!is_debuginfo_file (abfd)
153 && bfd_section_size (sect) > 0 && j == num_segments
154 && (bfd_section_flags (sect) & SEC_LOAD) != 0)
155 warning (_("Loadable section \"%s\" outside of ELF segments\n in %s"),
156 bfd_section_name (sect), bfd_get_filename (abfd));
157 }
158
159 return data;
160}
161
162/* We are called once per section from elf_symfile_read. We
163 need to examine each section we are passed, check to see
164 if it is something we are interested in processing, and
165 if so, stash away some access information for the section.
166
167 For now we recognize the dwarf debug information sections and
168 line number sections from matching their section names. The
169 ELF definition is no real help here since it has no direct
170 knowledge of DWARF (by design, so any debugging format can be
171 used).
172
173 We also recognize the ".stab" sections used by the Sun compilers
174 released with Solaris 2.
175
176 FIXME: The section names should not be hardwired strings (what
177 should they be? I don't think most object file formats have enough
178 section flags to specify what kind of debug section it is.
179 -kingdon). */
180
181static void
182elf_locate_sections (asection *sectp, struct elfinfo *ei)
183{
184 if (strcmp (sectp->name, ".stab") == 0)
185 {
186 ei->stabsect = sectp;
187 }
188 else if (strcmp (sectp->name, ".mdebug") == 0)
189 {
190 ei->mdebugsect = sectp;
191 }
192 else if (strcmp (sectp->name, ".ctf") == 0)
193 {
194 ei->ctfsect = sectp;
195 }
196}
197
198static struct minimal_symbol *
200 gdb::string_view name, bool copy_name,
201 unrelocated_addr address,
202 enum minimal_symbol_type ms_type,
203 asection *bfd_section, struct objfile *objfile)
204{
205 struct gdbarch *gdbarch = objfile->arch ();
206
207 if (ms_type == mst_text || ms_type == mst_file_text
208 || ms_type == mst_text_gnu_ifunc)
209 address
210 = unrelocated_addr (gdbarch_addr_bits_remove (gdbarch,
211 CORE_ADDR (address)));
212
213 /* We only setup section information for allocatable sections. Usually
214 we'd only expect to find msymbols for allocatable sections, but if the
215 ELF is malformed then this might not be the case. In that case don't
216 create an msymbol that references an uninitialised section object. */
217 int section_index = 0;
218 if ((bfd_section_flags (bfd_section) & SEC_ALLOC) == SEC_ALLOC
219 || bfd_section == bfd_abs_section_ptr)
220 section_index = gdb_bfd_section_index (objfile->obfd.get (), bfd_section);
221
222 return reader.record_full (name, copy_name, address, ms_type, section_index);
223}
224
225/* Read the symbol table of an ELF file.
226
227 Given an objfile, a symbol table, and a flag indicating whether the
228 symbol table contains regular, dynamic, or synthetic symbols, add all
229 the global function and data symbols to the minimal symbol table.
230
231 In stabs-in-ELF, as implemented by Sun, there are some local symbols
232 defined in the ELF symbol table, which can be used to locate
233 the beginnings of sections from each ".o" file that was linked to
234 form the executable objfile. We gather any such info and record it
235 in data structures hung off the objfile's private data. */
236
237#define ST_REGULAR 0
238#define ST_DYNAMIC 1
239#define ST_SYNTHETIC 2
240
241static void
243 struct objfile *objfile, int type,
244 long number_of_symbols, asymbol **symbol_table,
245 bool copy_names)
246{
247 struct gdbarch *gdbarch = objfile->arch ();
248 asymbol *sym;
249 long i;
250 CORE_ADDR symaddr;
251 enum minimal_symbol_type ms_type;
252 /* Name of the last file symbol. This is either a constant string or is
253 saved on the objfile's filename cache. */
254 const char *filesymname = "";
255 int stripped = (bfd_get_symcount (objfile->obfd.get ()) == 0);
256 int elf_make_msymbol_special_p
258
259 for (i = 0; i < number_of_symbols; i++)
260 {
261 sym = symbol_table[i];
262 if (sym->name == NULL || *sym->name == '\0')
263 {
264 /* Skip names that don't exist (shouldn't happen), or names
265 that are null strings (may happen). */
266 continue;
267 }
268
269 elf_symbol_type *elf_sym = (elf_symbol_type *) sym;
270
271 /* Skip "special" symbols, e.g. ARM mapping symbols. These are
272 symbols which do not correspond to objects in the symbol table,
273 but have some other target-specific meaning. */
274 if (bfd_is_target_special_symbol (objfile->obfd.get (), sym))
275 {
278 continue;
279 }
280
281 if (type == ST_DYNAMIC
282 && sym->section == bfd_und_section_ptr
283 && (sym->flags & BSF_FUNCTION))
284 {
285 struct minimal_symbol *msym;
286 bfd *abfd = objfile->obfd.get ();
287 asection *sect;
288
289 /* Symbol is a reference to a function defined in
290 a shared library.
291 If its value is non zero then it is usually the address
292 of the corresponding entry in the procedure linkage table,
293 plus the desired section offset.
294 If its value is zero then the dynamic linker has to resolve
295 the symbol. We are unable to find any meaningful address
296 for this symbol in the executable file, so we skip it. */
297 symaddr = sym->value;
298 if (symaddr == 0)
299 continue;
300
301 /* sym->section is the undefined section. However, we want to
302 record the section where the PLT stub resides with the
303 minimal symbol. Search the section table for the one that
304 covers the stub's address. */
305 for (sect = abfd->sections; sect != NULL; sect = sect->next)
306 {
307 if ((bfd_section_flags (sect) & SEC_ALLOC) == 0)
308 continue;
309
310 if (symaddr >= bfd_section_vma (sect)
311 && symaddr < bfd_section_vma (sect)
312 + bfd_section_size (sect))
313 break;
314 }
315 if (!sect)
316 continue;
317
318 /* On ia64-hpux, we have discovered that the system linker
319 adds undefined symbols with nonzero addresses that cannot
320 be right (their address points inside the code of another
321 function in the .text section). This creates problems
322 when trying to determine which symbol corresponds to
323 a given address.
324
325 We try to detect those buggy symbols by checking which
326 section we think they correspond to. Normally, PLT symbols
327 are stored inside their own section, and the typical name
328 for that section is ".plt". So, if there is a ".plt"
329 section, and yet the section name of our symbol does not
330 start with ".plt", we ignore that symbol. */
331 if (!startswith (sect->name, ".plt")
332 && bfd_get_section_by_name (abfd, ".plt") != NULL)
333 continue;
334
336 (reader, sym->name, copy_names,
337 unrelocated_addr (symaddr),
339 if (msym != NULL)
340 {
341 msym->filename = filesymname;
342 if (elf_make_msymbol_special_p)
344 }
345 continue;
346 }
347
348 /* If it is a nonstripped executable, do not enter dynamic
349 symbols, as the dynamic symbol table is usually a subset
350 of the main symbol table. */
351 if (type == ST_DYNAMIC && !stripped)
352 continue;
353 if (sym->flags & BSF_FILE)
354 filesymname = objfile->intern (sym->name);
355 else if (sym->flags & BSF_SECTION_SYM)
356 continue;
357 else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK
358 | BSF_GNU_UNIQUE))
359 {
360 struct minimal_symbol *msym;
361
362 /* Select global/local/weak symbols. Note that bfd puts abs
363 symbols in their own section, so all symbols we are
364 interested in will have a section. */
365 /* Bfd symbols are section relative. */
366 symaddr = sym->value + sym->section->vma;
367 /* For non-absolute symbols, use the type of the section
368 they are relative to, to intuit text/data. Bfd provides
369 no way of figuring this out for absolute symbols. */
370 if (sym->section == bfd_abs_section_ptr)
371 {
372 /* This is a hack to get the minimal symbol type
373 right for Irix 5, which has absolute addresses
374 with special section indices for dynamic symbols.
375
376 NOTE: uweigand-20071112: Synthetic symbols do not
377 have an ELF-private part, so do not touch those. */
378 unsigned int shndx = type == ST_SYNTHETIC ? 0 :
379 elf_sym->internal_elf_sym.st_shndx;
380
381 switch (shndx)
382 {
383 case SHN_MIPS_TEXT:
384 ms_type = mst_text;
385 break;
386 case SHN_MIPS_DATA:
387 ms_type = mst_data;
388 break;
389 case SHN_MIPS_ACOMMON:
390 ms_type = mst_bss;
391 break;
392 default:
393 ms_type = mst_abs;
394 }
395
396 /* If it is an Irix dynamic symbol, skip section name
397 symbols, relocate all others by section offset. */
398 if (ms_type != mst_abs)
399 {
400 if (sym->name[0] == '.')
401 continue;
402 }
403 }
404 else if (sym->section->flags & SEC_CODE)
405 {
406 if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
407 {
408 if (sym->flags & BSF_GNU_INDIRECT_FUNCTION)
409 ms_type = mst_text_gnu_ifunc;
410 else
411 ms_type = mst_text;
412 }
413 /* The BSF_SYNTHETIC check is there to omit ppc64 function
414 descriptors mistaken for static functions starting with 'L'.
415 */
416 else if ((sym->name[0] == '.' && sym->name[1] == 'L'
417 && (sym->flags & BSF_SYNTHETIC) == 0)
418 || ((sym->flags & BSF_LOCAL)
419 && sym->name[0] == '$'
420 && sym->name[1] == 'L'))
421 /* Looks like a compiler-generated label. Skip
422 it. The assembler should be skipping these (to
423 keep executables small), but apparently with
424 gcc on the (deleted) delta m88k SVR4, it loses.
425 So to have us check too should be harmless (but
426 I encourage people to fix this in the assembler
427 instead of adding checks here). */
428 continue;
429 else
430 {
431 ms_type = mst_file_text;
432 }
433 }
434 else if (sym->section->flags & SEC_ALLOC)
435 {
436 if (sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_GNU_UNIQUE))
437 {
438 if (sym->flags & BSF_GNU_INDIRECT_FUNCTION)
439 {
440 ms_type = mst_data_gnu_ifunc;
441 }
442 else if (sym->section->flags & SEC_LOAD)
443 {
444 ms_type = mst_data;
445 }
446 else
447 {
448 ms_type = mst_bss;
449 }
450 }
451 else if (sym->flags & BSF_LOCAL)
452 {
453 if (sym->section->flags & SEC_LOAD)
454 {
455 ms_type = mst_file_data;
456 }
457 else
458 {
459 ms_type = mst_file_bss;
460 }
461 }
462 else
463 {
464 ms_type = mst_unknown;
465 }
466 }
467 else
468 {
469 /* FIXME: Solaris2 shared libraries include lots of
470 odd "absolute" and "undefined" symbols, that play
471 hob with actions like finding what function the PC
472 is in. Ignore them if they aren't text, data, or bss. */
473 /* ms_type = mst_unknown; */
474 continue; /* Skip this symbol. */
475 }
477 (reader, sym->name, copy_names, unrelocated_addr (symaddr),
478 ms_type, sym->section, objfile);
479
480 if (msym)
481 {
482 /* NOTE: uweigand-20071112: A synthetic symbol does not have an
483 ELF-private part. */
484 if (type != ST_SYNTHETIC)
485 {
486 /* Pass symbol size field in via BFD. FIXME!!! */
487 msym->set_size (elf_sym->internal_elf_sym.st_size);
488 }
489
490 msym->filename = filesymname;
491 if (elf_make_msymbol_special_p)
493 }
494
495 /* If we see a default versioned symbol, install it under
496 its version-less name. */
497 if (msym != NULL)
498 {
499 const char *atsign = strchr (sym->name, '@');
500 bool is_at_symbol = atsign != nullptr && atsign > sym->name;
501 bool is_plt = is_at_symbol && strcmp (atsign, "@plt") == 0;
502 int len = is_at_symbol ? atsign - sym->name : 0;
503
504 if (is_at_symbol
505 && !is_plt
506 && (elf_sym->version & VERSYM_HIDDEN) == 0)
507 record_minimal_symbol (reader,
508 gdb::string_view (sym->name, len),
509 true, unrelocated_addr (symaddr),
510 ms_type, sym->section, objfile);
511 else if (is_plt)
512 {
513 /* For @plt symbols, also record a trampoline to the
514 destination symbol. The @plt symbol will be used
515 in disassembly, and the trampoline will be used
516 when we are trying to find the target. */
517 if (ms_type == mst_text && type == ST_SYNTHETIC)
518 {
519 struct minimal_symbol *mtramp;
520
521 mtramp = record_minimal_symbol
522 (reader, gdb::string_view (sym->name, len), true,
523 unrelocated_addr (symaddr),
524 mst_solib_trampoline, sym->section, objfile);
525 if (mtramp)
526 {
527 mtramp->set_size (msym->size());
528 mtramp->created_by_gdb = 1;
529 mtramp->filename = filesymname;
530 if (elf_make_msymbol_special_p)
532 sym, mtramp);
533 }
534 }
535 }
536 }
537 }
538 }
539}
540
541/* Build minimal symbols named `function@got.plt' (see SYMBOL_GOT_PLT_SUFFIX)
542 for later look ups of which function to call when user requests
543 a STT_GNU_IFUNC function. As the STT_GNU_IFUNC type is found at the target
544 library defining `function' we cannot yet know while reading OBJFILE which
545 of the SYMBOL_GOT_PLT_SUFFIX entries will be needed and later
546 DYN_SYMBOL_TABLE is no longer easily available for OBJFILE. */
547
548static void
550 struct objfile *objfile, asymbol **dyn_symbol_table)
551{
552 bfd *obfd = objfile->obfd.get ();
553 const struct elf_backend_data *bed = get_elf_backend_data (obfd);
554 asection *relplt, *got_plt;
555 bfd_size_type reloc_count, reloc;
556 struct gdbarch *gdbarch = objfile->arch ();
557 struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
558 size_t ptr_size = ptr_type->length ();
559
561 return;
562
563 got_plt = bfd_get_section_by_name (obfd, ".got.plt");
564 if (got_plt == NULL)
565 {
566 /* For platforms where there is no separate .got.plt. */
567 got_plt = bfd_get_section_by_name (obfd, ".got");
568 if (got_plt == NULL)
569 return;
570 }
571
572 /* Depending on system, we may find jump slots in a relocation
573 section for either .got.plt or .plt. */
574 asection *plt = bfd_get_section_by_name (obfd, ".plt");
575 int plt_elf_idx = (plt != NULL) ? elf_section_data (plt)->this_idx : -1;
576
577 int got_plt_elf_idx = elf_section_data (got_plt)->this_idx;
578
579 /* This search algorithm is from _bfd_elf_canonicalize_dynamic_reloc. */
580 for (relplt = obfd->sections; relplt != NULL; relplt = relplt->next)
581 {
582 const auto &this_hdr = elf_section_data (relplt)->this_hdr;
583
584 if (this_hdr.sh_type == SHT_REL || this_hdr.sh_type == SHT_RELA)
585 {
586 if (this_hdr.sh_info == plt_elf_idx
587 || this_hdr.sh_info == got_plt_elf_idx)
588 break;
589 }
590 }
591 if (relplt == NULL)
592 return;
593
594 if (! bed->s->slurp_reloc_table (obfd, relplt, dyn_symbol_table, TRUE))
595 return;
596
597 std::string string_buffer;
598
599 /* Does ADDRESS reside in SECTION of OBFD? */
600 auto within_section = [obfd] (asection *section, CORE_ADDR address)
601 {
602 if (section == NULL)
603 return false;
604
605 return (bfd_section_vma (section) <= address
606 && (address < bfd_section_vma (section)
607 + bfd_section_size (section)));
608 };
609
610 reloc_count = relplt->size / elf_section_data (relplt)->this_hdr.sh_entsize;
611 for (reloc = 0; reloc < reloc_count; reloc++)
612 {
613 const char *name;
614 struct minimal_symbol *msym;
615 CORE_ADDR address;
616 const char *got_suffix = SYMBOL_GOT_PLT_SUFFIX;
617 const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
618
619 name = bfd_asymbol_name (*relplt->relocation[reloc].sym_ptr_ptr);
620 address = relplt->relocation[reloc].address;
621
622 asection *msym_section;
623
624 /* Does the pointer reside in either the .got.plt or .plt
625 sections? */
626 if (within_section (got_plt, address))
627 msym_section = got_plt;
628 else if (within_section (plt, address))
629 msym_section = plt;
630 else
631 continue;
632
633 /* We cannot check if NAME is a reference to
634 mst_text_gnu_ifunc/mst_data_gnu_ifunc as in OBJFILE the
635 symbol is undefined and the objfile having NAME defined may
636 not yet have been loaded. */
637
638 string_buffer.assign (name);
639 string_buffer.append (got_suffix, got_suffix + got_suffix_len);
640
641 msym = record_minimal_symbol (reader, string_buffer,
642 true, unrelocated_addr (address),
643 mst_slot_got_plt, msym_section, objfile);
644 if (msym)
645 msym->set_size (ptr_size);
646 }
647}
648
649/* The data pointer is htab_t for gnu_ifunc_record_cache_unchecked. */
650
651static const registry<objfile>::key<htab, htab_deleter>
653
654/* Map function names to CORE_ADDR in elf_objfile_gnu_ifunc_cache_data. */
655
657{
658 /* This is always a function entry address, not a function descriptor. */
659 CORE_ADDR addr;
660
661 char name[1];
662};
663
664/* htab_hash for elf_objfile_gnu_ifunc_cache_data. */
665
666static hashval_t
667elf_gnu_ifunc_cache_hash (const void *a_voidp)
668{
669 const struct elf_gnu_ifunc_cache *a
670 = (const struct elf_gnu_ifunc_cache *) a_voidp;
671
672 return htab_hash_string (a->name);
673}
674
675/* htab_eq for elf_objfile_gnu_ifunc_cache_data. */
676
677static int
678elf_gnu_ifunc_cache_eq (const void *a_voidp, const void *b_voidp)
679{
680 const struct elf_gnu_ifunc_cache *a
681 = (const struct elf_gnu_ifunc_cache *) a_voidp;
682 const struct elf_gnu_ifunc_cache *b
683 = (const struct elf_gnu_ifunc_cache *) b_voidp;
684
685 return strcmp (a->name, b->name) == 0;
686}
687
688/* Record the target function address of a STT_GNU_IFUNC function NAME is the
689 function entry address ADDR. Return 1 if NAME and ADDR are considered as
690 valid and therefore they were successfully recorded, return 0 otherwise.
691
692 Function does not expect a duplicate entry. Use
693 elf_gnu_ifunc_resolve_by_cache first to check if the entry for NAME already
694 exists. */
695
696static int
697elf_gnu_ifunc_record_cache (const char *name, CORE_ADDR addr)
698{
699 struct bound_minimal_symbol msym;
700 struct objfile *objfile;
701 htab_t htab;
702 struct elf_gnu_ifunc_cache entry_local, *entry_p;
703 void **slot;
704
706 if (msym.minsym == NULL)
707 return 0;
708 if (msym.value_address () != addr)
709 return 0;
710 objfile = msym.objfile;
711
712 /* If .plt jumps back to .plt the symbol is still deferred for later
713 resolution and it has no use for GDB. */
714 const char *target_name = msym.minsym->linkage_name ();
715 size_t len = strlen (target_name);
716
717 /* Note we check the symbol's name instead of checking whether the
718 symbol is in the .plt section because some systems have @plt
719 symbols in the .text section. */
720 if (len > 4 && strcmp (target_name + len - 4, "@plt") == 0)
721 return 0;
722
723 if (strcmp (target_name, "_PROCEDURE_LINKAGE_TABLE_") == 0)
724 return 0;
725
727 if (htab == NULL)
728 {
729 htab = htab_create_alloc (1, elf_gnu_ifunc_cache_hash,
731 NULL, xcalloc, xfree);
733 }
734
735 entry_local.addr = addr;
736 obstack_grow (&objfile->objfile_obstack, &entry_local,
737 offsetof (struct elf_gnu_ifunc_cache, name));
738 obstack_grow_str0 (&objfile->objfile_obstack, name);
739 entry_p
740 = (struct elf_gnu_ifunc_cache *) obstack_finish (&objfile->objfile_obstack);
741
742 slot = htab_find_slot (htab, entry_p, INSERT);
743 if (*slot != NULL)
744 {
745 struct elf_gnu_ifunc_cache *entry_found_p
746 = (struct elf_gnu_ifunc_cache *) *slot;
747 struct gdbarch *gdbarch = objfile->arch ();
748
749 if (entry_found_p->addr != addr)
750 {
751 /* This case indicates buggy inferior program, the resolved address
752 should never change. */
753
754 warning (_("gnu-indirect-function \"%s\" has changed its resolved "
755 "function_address from %s to %s"),
756 name, paddress (gdbarch, entry_found_p->addr),
757 paddress (gdbarch, addr));
758 }
759
760 /* New ENTRY_P is here leaked/duplicate in the OBJFILE obstack. */
761 }
762 *slot = entry_p;
763
764 return 1;
765}
766
767/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
768 function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
769 is not NULL) and the function returns 1. It returns 0 otherwise.
770
771 Only the elf_objfile_gnu_ifunc_cache_data hash table is searched by this
772 function. */
773
774static int
775elf_gnu_ifunc_resolve_by_cache (const char *name, CORE_ADDR *addr_p)
776{
777 int found = 0;
778
779 /* FIXME: we only search the initial namespace.
780
781 To search other namespaces, we would need to provide context, e.g. in
782 form of an objfile in that namespace. */
784 (target_gdbarch (),
785 [name, &addr_p, &found] (struct objfile *objfile)
786 {
787 htab_t htab;
788 elf_gnu_ifunc_cache *entry_p;
789 void **slot;
790
792 if (htab == NULL)
793 return 0;
794
795 entry_p = ((elf_gnu_ifunc_cache *)
796 alloca (sizeof (*entry_p) + strlen (name)));
797 strcpy (entry_p->name, name);
798
799 slot = htab_find_slot (htab, entry_p, NO_INSERT);
800 if (slot == NULL)
801 return 0;
802 entry_p = (elf_gnu_ifunc_cache *) *slot;
803 gdb_assert (entry_p != NULL);
804
805 if (addr_p)
806 *addr_p = entry_p->addr;
807
808 found = 1;
809 return 1;
810 }, nullptr);
811
812 return found;
813}
814
815/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
816 function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
817 is not NULL) and the function returns 1. It returns 0 otherwise.
818
819 Only the SYMBOL_GOT_PLT_SUFFIX locations are searched by this function.
820 elf_gnu_ifunc_resolve_by_cache must have been already called for NAME to
821 prevent cache entries duplicates. */
822
823static int
824elf_gnu_ifunc_resolve_by_got (const char *name, CORE_ADDR *addr_p)
825{
826 char *name_got_plt;
827 const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
828 int found = 0;
829
830 name_got_plt = (char *) alloca (strlen (name) + got_suffix_len + 1);
831 sprintf (name_got_plt, "%s" SYMBOL_GOT_PLT_SUFFIX, name);
832
833 /* FIXME: we only search the initial namespace.
834
835 To search other namespaces, we would need to provide context, e.g. in
836 form of an objfile in that namespace. */
838 (target_gdbarch (),
839 [name, name_got_plt, &addr_p, &found] (struct objfile *objfile)
840 {
841 bfd *obfd = objfile->obfd.get ();
842 struct gdbarch *gdbarch = objfile->arch ();
844 size_t ptr_size = ptr_type->length ();
845 CORE_ADDR pointer_address, addr;
846 asection *plt;
847 gdb_byte *buf = (gdb_byte *) alloca (ptr_size);
849
850 msym = lookup_minimal_symbol (name_got_plt, NULL, objfile);
851 if (msym.minsym == NULL)
852 return 0;
853 if (msym.minsym->type () != mst_slot_got_plt)
854 return 0;
855 pointer_address = msym.value_address ();
856
857 plt = bfd_get_section_by_name (obfd, ".plt");
858 if (plt == NULL)
859 return 0;
860
861 if (msym.minsym->size () != ptr_size)
862 return 0;
863 if (target_read_memory (pointer_address, buf, ptr_size) != 0)
864 return 0;
865 addr = extract_typed_address (buf, ptr_type);
867 (gdbarch, addr, current_inferior ()->top_target ());
868 addr = gdbarch_addr_bits_remove (gdbarch, addr);
869
871 {
872 if (addr_p != NULL)
873 *addr_p = addr;
874
875 found = 1;
876 return 1;
877 }
878
879 return 0;
880 }, nullptr);
881
882 return found;
883}
884
885/* Try to find the target resolved function entry address of a STT_GNU_IFUNC
886 function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
887 is not NULL) and the function returns true. It returns false otherwise.
888
889 Both the elf_objfile_gnu_ifunc_cache_data hash table and
890 SYMBOL_GOT_PLT_SUFFIX locations are searched by this function. */
891
892static bool
893elf_gnu_ifunc_resolve_name (const char *name, CORE_ADDR *addr_p)
894{
896 return true;
897
899 return true;
900
901 return false;
902}
903
904/* Call STT_GNU_IFUNC - a function returning addresss of a real function to
905 call. PC is theSTT_GNU_IFUNC resolving function entry. The value returned
906 is the entry point of the resolved STT_GNU_IFUNC target function to call.
907 */
908
909static CORE_ADDR
911{
912 const char *name_at_pc;
913 CORE_ADDR start_at_pc, address;
914 struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
915 struct value *function, *address_val;
916 CORE_ADDR hwcap = 0;
917 struct value *hwcap_val;
918
919 /* Try first any non-intrusive methods without an inferior call. */
920
921 if (find_pc_partial_function (pc, &name_at_pc, &start_at_pc, NULL)
922 && start_at_pc == pc)
923 {
924 if (elf_gnu_ifunc_resolve_name (name_at_pc, &address))
925 return address;
926 }
927 else
928 name_at_pc = NULL;
929
930 function = value::allocate (func_func_type);
931 function->set_lval (lval_memory);
932 function->set_address (pc);
933
934 /* STT_GNU_IFUNC resolver functions usually receive the HWCAP vector as
935 parameter. FUNCTION is the function entry address. ADDRESS may be a
936 function descriptor. */
937
938 target_auxv_search (AT_HWCAP, &hwcap);
940 ->builtin_unsigned_long, hwcap);
941 address_val = call_function_by_hand (function, NULL, hwcap_val);
942 address = value_as_address (address_val);
944 (gdbarch, address, current_inferior ()->top_target ());
946
947 if (name_at_pc)
949
950 return address;
951}
952
953/* Handle inferior hit of bp_gnu_ifunc_resolver, see its definition. */
954
955static void
957{
958 struct breakpoint *b_return;
960 struct frame_id prev_frame_id = get_stack_frame_id (prev_frame);
961 CORE_ADDR prev_pc = get_frame_pc (prev_frame);
962 int thread_id = inferior_thread ()->global_num;
963
964 gdb_assert (b->type == bp_gnu_ifunc_resolver);
965
966 for (b_return = b->related_breakpoint; b_return != b;
967 b_return = b_return->related_breakpoint)
968 {
969 gdb_assert (b_return->type == bp_gnu_ifunc_resolver_return);
970 gdb_assert (b_return->has_single_location ());
971 gdb_assert (frame_id_p (b_return->frame_id));
972
973 if (b_return->thread == thread_id
974 && b_return->first_loc ().requested_address == prev_pc
975 && b_return->frame_id == prev_frame_id)
976 break;
977 }
978
979 if (b_return == b)
980 {
981 /* No need to call find_pc_line for symbols resolving as this is only
982 a helper breakpointer never shown to the user. */
983
984 symtab_and_line sal;
986 sal.pc = prev_pc;
987 sal.section = find_pc_overlay (sal.pc);
988 sal.explicit_pc = 1;
989 b_return
990 = set_momentary_breakpoint (get_frame_arch (prev_frame), sal,
991 prev_frame_id,
993
994 /* set_momentary_breakpoint invalidates PREV_FRAME. */
995 prev_frame = NULL;
996
997 /* Add new b_return to the ring list b->related_breakpoint. */
998 gdb_assert (b_return->related_breakpoint == b_return);
1000 b->related_breakpoint = b_return;
1001 }
1002}
1003
1004/* Handle inferior hit of bp_gnu_ifunc_resolver_return, see its definition. */
1005
1006static void
1008{
1009 thread_info *thread = inferior_thread ();
1011 struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
1012 struct type *value_type = func_func_type->target_type ();
1013 struct regcache *regcache = get_thread_regcache (thread);
1014 struct value *func_func;
1015 struct value *value;
1016 CORE_ADDR resolved_address, resolved_pc;
1017
1018 gdb_assert (b->type == bp_gnu_ifunc_resolver_return);
1019
1020 while (b->related_breakpoint != b)
1021 {
1022 struct breakpoint *b_next = b->related_breakpoint;
1023
1024 switch (b->type)
1025 {
1027 break;
1030 break;
1031 default:
1032 internal_error (_("handle_inferior_event: Invalid "
1033 "gnu-indirect-function breakpoint type %d"),
1034 (int) b->type);
1035 }
1036 b = gdb::checked_static_cast<code_breakpoint *> (b_next);
1037 }
1038 gdb_assert (b->type == bp_gnu_ifunc_resolver);
1039 gdb_assert (b->has_single_location ());
1040
1041 func_func = value::allocate (func_func_type);
1042 func_func->set_lval (lval_memory);
1043 func_func->set_address (b->first_loc ().related_address);
1044
1045 value = value::allocate (value_type);
1046 gdbarch_return_value_as_value (gdbarch, func_func, value_type, regcache,
1047 &value, NULL);
1048 resolved_address = value_as_address (value);
1050 (gdbarch, resolved_address, current_inferior ()->top_target ());
1051 resolved_pc = gdbarch_addr_bits_remove (gdbarch, resolved_pc);
1052
1053 gdb_assert (current_program_space == b->pspace || b->pspace == NULL);
1054 elf_gnu_ifunc_record_cache (b->locspec->to_string (), resolved_pc);
1055
1056 b->type = bp_breakpoint;
1058 find_function_start_sal (resolved_pc, NULL, true),
1059 {});
1060}
1061
1062/* A helper function for elf_symfile_read that reads the minimal
1063 symbols. */
1064
1065static void
1066elf_read_minimal_symbols (struct objfile *objfile, int symfile_flags,
1067 const struct elfinfo *ei)
1068{
1069 bfd *synth_abfd, *abfd = objfile->obfd.get ();
1070 long symcount = 0, dynsymcount = 0, synthcount, storage_needed;
1071 asymbol **symbol_table = NULL, **dyn_symbol_table = NULL;
1072 asymbol *synthsyms;
1073
1074 symtab_create_debug_printf ("reading minimal symbols of objfile %s",
1076
1077 /* If we already have minsyms, then we can skip some work here.
1078 However, if there were stabs or mdebug sections, we go ahead and
1079 redo all the work anyway, because the psym readers for those
1080 kinds of debuginfo need extra information found here. This can
1081 go away once all types of symbols are in the per-BFD object. */
1083 && ei->stabsect == NULL
1084 && ei->mdebugsect == NULL
1085 && ei->ctfsect == NULL)
1086 {
1087 symtab_create_debug_printf ("minimal symbols were previously read");
1088 return;
1089 }
1090
1092
1093 /* Process the normal ELF symbol table first. */
1094
1095 storage_needed = bfd_get_symtab_upper_bound (objfile->obfd.get ());
1096 if (storage_needed < 0)
1097 error (_("Can't read symbols from %s: %s"),
1098 bfd_get_filename (objfile->obfd.get ()),
1099 bfd_errmsg (bfd_get_error ()));
1100
1101 if (storage_needed > 0)
1102 {
1103 /* Memory gets permanently referenced from ABFD after
1104 bfd_canonicalize_symtab so it must not get freed before ABFD gets. */
1105
1106 symbol_table = (asymbol **) bfd_alloc (abfd, storage_needed);
1107 symcount = bfd_canonicalize_symtab (objfile->obfd.get (), symbol_table);
1108
1109 if (symcount < 0)
1110 error (_("Can't read symbols from %s: %s"),
1111 bfd_get_filename (objfile->obfd.get ()),
1112 bfd_errmsg (bfd_get_error ()));
1113
1114 elf_symtab_read (reader, objfile, ST_REGULAR, symcount, symbol_table,
1115 false);
1116 }
1117
1118 /* Add the dynamic symbols. */
1119
1120 storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd.get ());
1121
1122 if (storage_needed > 0)
1123 {
1124 /* Memory gets permanently referenced from ABFD after
1125 bfd_get_synthetic_symtab so it must not get freed before ABFD gets.
1126 It happens only in the case when elf_slurp_reloc_table sees
1127 asection->relocation NULL. Determining which section is asection is
1128 done by _bfd_elf_get_synthetic_symtab which is all a bfd
1129 implementation detail, though. */
1130
1131 dyn_symbol_table = (asymbol **) bfd_alloc (abfd, storage_needed);
1132 dynsymcount = bfd_canonicalize_dynamic_symtab (objfile->obfd.get (),
1133 dyn_symbol_table);
1134
1135 if (dynsymcount < 0)
1136 error (_("Can't read symbols from %s: %s"),
1137 bfd_get_filename (objfile->obfd.get ()),
1138 bfd_errmsg (bfd_get_error ()));
1139
1140 elf_symtab_read (reader, objfile, ST_DYNAMIC, dynsymcount,
1141 dyn_symbol_table, false);
1142
1143 elf_rel_plt_read (reader, objfile, dyn_symbol_table);
1144 }
1145
1146 /* Contrary to binutils --strip-debug/--only-keep-debug the strip command from
1147 elfutils (eu-strip) moves even the .symtab section into the .debug file.
1148
1149 bfd_get_synthetic_symtab on ppc64 for each function descriptor ELF symbol
1150 'name' creates a new BSF_SYNTHETIC ELF symbol '.name' with its code
1151 address. But with eu-strip files bfd_get_synthetic_symtab would fail to
1152 read the code address from .opd while it reads the .symtab section from
1153 a separate debug info file as the .opd section is SHT_NOBITS there.
1154
1155 With SYNTH_ABFD the .opd section will be read from the original
1156 backlinked binary where it is valid. */
1157
1159 synth_abfd = objfile->separate_debug_objfile_backlink->obfd.get ();
1160 else
1161 synth_abfd = abfd;
1162
1163 /* Add synthetic symbols - for instance, names for any PLT entries. */
1164
1165 synthcount = bfd_get_synthetic_symtab (synth_abfd, symcount, symbol_table,
1166 dynsymcount, dyn_symbol_table,
1167 &synthsyms);
1168 if (synthcount > 0)
1169 {
1170 long i;
1171
1172 std::unique_ptr<asymbol *[]>
1173 synth_symbol_table (new asymbol *[synthcount]);
1174 for (i = 0; i < synthcount; i++)
1175 synth_symbol_table[i] = synthsyms + i;
1176 elf_symtab_read (reader, objfile, ST_SYNTHETIC, synthcount,
1177 synth_symbol_table.get (), true);
1178
1179 xfree (synthsyms);
1180 synthsyms = NULL;
1181 }
1182
1183 /* Install any minimal symbols that have been collected as the current
1184 minimal symbols for this objfile. The debug readers below this point
1185 should not generate new minimal symbols; if they do it's their
1186 responsibility to install them. "mdebug" appears to be the only one
1187 which will do this. */
1188
1189 reader.install ();
1190
1191 symtab_create_debug_printf ("done reading minimal symbols");
1192}
1193
1194/* Dwarf-specific helper for elf_symfile_read. Return true if we managed to
1195 load dwarf debug info. */
1196
1197static bool
1199 symfile_add_flags symfile_flags)
1200{
1201 bool has_dwarf2 = true;
1202
1203 if (dwarf2_has_info (objfile, NULL, true))
1205 /* If the file has its own symbol tables it has no separate debug
1206 info. `.dynsym'/`.symtab' go to MSYMBOLS, `.debug_info' goes to
1207 SYMTABS/PSYMTABS. `.gnu_debuglink' may no longer be present with
1208 `.note.gnu.build-id'.
1209
1210 .gnu_debugdata is !objfile::has_partial_symbols because it contains only
1211 .symtab, not .debug_* section. But if we already added .gnu_debugdata as
1212 an objfile via find_separate_debug_file_in_section there was no separate
1213 debug info available. Therefore do not attempt to search for another one,
1214 objfile->separate_debug_objfile->separate_debug_objfile GDB guarantees to
1215 be NULL and we would possibly violate it. */
1216
1217 else if (!objfile->has_partial_symbols ()
1220 {
1221 deferred_warnings warnings;
1222
1223 std::string debugfile
1225
1226 if (debugfile.empty ())
1227 debugfile = find_separate_debug_file_by_debuglink (objfile, &warnings);
1228
1229 if (!debugfile.empty ())
1230 {
1231 gdb_bfd_ref_ptr debug_bfd
1232 (symfile_bfd_open_no_error (debugfile.c_str ()));
1233
1234 if (debug_bfd != nullptr)
1235 symbol_file_add_separate (debug_bfd, debugfile.c_str (),
1236 symfile_flags, objfile);
1237 }
1238 else
1239 {
1240 has_dwarf2 = false;
1241 const struct bfd_build_id *build_id
1242 = build_id_bfd_get (objfile->obfd.get ());
1243 const char *filename = bfd_get_filename (objfile->obfd.get ());
1244
1245 if (build_id != nullptr)
1246 {
1247 gdb::unique_xmalloc_ptr<char> symfile_path;
1248 scoped_fd fd (debuginfod_debuginfo_query (build_id->data,
1249 build_id->size,
1250 filename,
1251 &symfile_path));
1252
1253 if (fd.get () >= 0)
1254 {
1255 /* File successfully retrieved from server. */
1256 gdb_bfd_ref_ptr debug_bfd
1257 (symfile_bfd_open_no_error (symfile_path.get ()));
1258
1259 if (debug_bfd != nullptr
1260 && build_id_verify (debug_bfd.get (), build_id->size,
1261 build_id->data))
1262 {
1263 symbol_file_add_separate (debug_bfd, symfile_path.get (),
1264 symfile_flags, objfile);
1265 has_dwarf2 = true;
1266 }
1267 }
1268 }
1269 }
1270 /* If all the methods to collect the debuginfo failed, print the
1271 warnings, this is a no-op if there are no warnings. */
1272 if (debugfile.empty () && !has_dwarf2)
1273 warnings.emit ();
1274 }
1275
1276 return has_dwarf2;
1277}
1278
1279/* Scan and build partial symbols for a symbol file.
1280 We have been initialized by a call to elf_symfile_init, which
1281 currently does nothing.
1282
1283 This function only does the minimum work necessary for letting the
1284 user "name" things symbolically; it does not read the entire symtab.
1285 Instead, it reads the external and static symbols and puts them in partial
1286 symbol tables. When more extensive information is requested of a
1287 file, the corresponding partial symbol table is mutated into a full
1288 fledged symbol table by going back and reading the symbols
1289 for real.
1290
1291 We look for sections with specific names, to tell us what debug
1292 format to look for: FIXME!!!
1293
1294 elfstab_build_psymtabs() handles STABS symbols;
1295 mdebug_build_psymtabs() handles ECOFF debugging information.
1296
1297 Note that ELF files have a "minimal" symbol table, which looks a lot
1298 like a COFF symbol table, but has only the minimal information necessary
1299 for linking. We process this also, and use the information to
1300 build gdb's minimal symbol table. This gives us some minimal debugging
1301 capability even for files compiled without -g. */
1302
1303static void
1304elf_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
1305{
1306 bfd *abfd = objfile->obfd.get ();
1307 struct elfinfo ei;
1308
1309 memset ((char *) &ei, 0, sizeof (ei));
1310 if (!(objfile->flags & OBJF_READNEVER))
1311 {
1312 for (asection *sect : gdb_bfd_sections (abfd))
1313 elf_locate_sections (sect, &ei);
1314 }
1315
1316 elf_read_minimal_symbols (objfile, symfile_flags, &ei);
1317
1318 /* ELF debugging information is inserted into the psymtab in the
1319 order of least informative first - most informative last. Since
1320 the psymtab table is searched `most recent insertion first' this
1321 increases the probability that more detailed debug information
1322 for a section is found.
1323
1324 For instance, an object file might contain both .mdebug (XCOFF)
1325 and .debug_info (DWARF2) sections then .mdebug is inserted first
1326 (searched last) and DWARF2 is inserted last (searched first). If
1327 we don't do this then the XCOFF info is found first - for code in
1328 an included file XCOFF info is useless. */
1329
1330 if (ei.mdebugsect)
1331 {
1332 const struct ecoff_debug_swap *swap;
1333
1334 /* .mdebug section, presumably holding ECOFF debugging
1335 information. */
1336 swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap;
1337 if (swap)
1339 }
1340 if (ei.stabsect)
1341 {
1342 asection *str_sect;
1343
1344 /* Stab sections have an associated string table that looks like
1345 a separate section. */
1346 str_sect = bfd_get_section_by_name (abfd, ".stabstr");
1347
1348 /* FIXME should probably warn about a stab section without a stabstr. */
1349 if (str_sect)
1351 ei.stabsect,
1352 str_sect->filepos,
1353 bfd_section_size (str_sect));
1354 }
1355
1356 /* Read the CTF section only if there is no DWARF info. */
1357 if (always_read_ctf && ei.ctfsect)
1358 {
1360 }
1361
1362 bool has_dwarf2 = elf_symfile_read_dwarf2 (objfile, symfile_flags);
1363
1364 /* Read the CTF section only if there is no DWARF info. */
1365 if (!always_read_ctf && !has_dwarf2 && ei.ctfsect)
1366 {
1368 }
1369
1370 /* Copy relocations are used by some ABIs using the ELF format, so
1371 set the objfile flag indicating this fact. */
1373}
1374
1375/* Initialize anything that needs initializing when a completely new symbol
1376 file is specified (not just adding some symbols from another file, e.g. a
1377 shared library). */
1378
1379static void
1380elf_new_init (struct objfile *ignore)
1381{
1382}
1383
1384/* Perform any local cleanups required when we are done with a particular
1385 objfile. I.E, we are in the process of discarding all symbol information
1386 for an objfile, freeing up all memory held for it, and unlinking the
1387 objfile struct from the global list of known objfiles. */
1388
1389static void
1391{
1392}
1393
1394/* ELF specific initialization routine for reading symbols. */
1395
1396static void
1398{
1399}
1400
1401/* Implementation of `sym_get_probes', as documented in symfile.h. */
1402
1403static const elfread_data &
1405{
1406 elfread_data *probes_per_bfd = probe_key.get (objfile->obfd.get ());
1407
1408 if (probes_per_bfd == NULL)
1409 {
1410 probes_per_bfd = probe_key.emplace (objfile->obfd.get ());
1411
1412 /* Here we try to gather information about all types of probes from the
1413 objfile. */
1414 for (const static_probe_ops *ops : all_static_probe_ops)
1415 ops->get_probes (probes_per_bfd, objfile);
1416 }
1417
1418 return *probes_per_bfd;
1419}
1420
1421
1422
1423/* Implementation `sym_probe_fns', as documented in symfile.h. */
1424
1425static const struct sym_probe_fns elf_probe_fns =
1426{
1427 elf_get_probes, /* sym_get_probes */
1428};
1429
1430/* Register that we are able to handle ELF object file formats. */
1431
1432static const struct sym_fns elf_sym_fns =
1433{
1434 elf_new_init, /* init anything gbl to entire symtab */
1435 elf_symfile_init, /* read initial info, setup for sym_read() */
1436 elf_symfile_read, /* read a symbol file into symtab */
1437 elf_symfile_finish, /* finished with file, cleanup */
1438 default_symfile_offsets, /* Translate ext. to int. relocation */
1439 elf_symfile_segments, /* Get segment information from a file. */
1440 NULL,
1441 default_symfile_relocate, /* Relocate a debug section. */
1442 &elf_probe_fns, /* sym_probe_fns */
1443};
1444
1445/* STT_GNU_IFUNC resolver vector to be installed to gnu_ifunc_fns_p. */
1446
1454
1455void _initialize_elfread ();
1456void
1458{
1459 add_symtab_fns (bfd_target_elf_flavour, &elf_sym_fns);
1460
1462
1463 /* Add "set always-read-ctf on/off". */
1465 _("\
1466Set whether CTF is always read."),
1467 _("\
1468Show whether CTF is always read."),
1469 _("\
1470When off, CTF is only read if DWARF is not present. When on, CTF is read\
1471 regardless of whether DWARF is present."),
1472 nullptr /* set_func */, nullptr /* show_func */,
1473 &setlist, &showlist);
1474}
const char *const name
void xfree(void *)
void * xcalloc(size_t number, size_t size)
Definition alloc.c:85
struct gdbarch * target_gdbarch(void)
int target_auxv_search(const gdb::byte_vector &auxv, target_ops *ops, gdbarch *gdbarch, CORE_ADDR match, CORE_ADDR *valp)
Definition auxv.c:385
bool find_pc_partial_function(CORE_ADDR pc, const char **name, CORE_ADDR *address, CORE_ADDR *endaddr, const struct block **block)
Definition blockframe.c:373
void delete_breakpoint(struct breakpoint *bpt)
breakpoint_up set_momentary_breakpoint(struct gdbarch *gdbarch, struct symtab_and_line sal, struct frame_id frame_id, enum bptype type)
void update_breakpoint_locations(code_breakpoint *b, struct program_space *filter_pspace, gdb::array_view< const symtab_and_line > sals, gdb::array_view< const symtab_and_line > sals_end)
@ bp_gnu_ifunc_resolver_return
Definition breakpoint.h:211
@ bp_breakpoint
Definition breakpoint.h:86
@ bp_gnu_ifunc_resolver
Definition breakpoint.h:205
std::string find_separate_debug_file_by_buildid(struct objfile *objfile, deferred_warnings *warnings)
Definition build-id.c:212
int build_id_verify(bfd *abfd, size_t check_len, const bfd_byte *check)
Definition build-id.c:56
const struct bfd_build_id * build_id_bfd_get(bfd *abfd)
Definition build-id.c:34
CORE_ADDR requested_address
Definition breakpoint.h:458
CORE_ADDR related_address
Definition breakpoint.h:463
struct program_space * pspace
Definition inferior.h:582
struct minimal_symbol * record_full(gdb::string_view name, bool copy_name, unrelocated_addr address, enum minimal_symbol_type ms_type, int section)
Definition minsyms.c:1173
void set(unsigned key, void *datum)
Definition registry.h:204
void * get(unsigned key)
Definition registry.h:211
struct cmd_list_element * showlist
Definition cli-cmds.c:127
struct cmd_list_element * setlist
Definition cli-cmds.c:119
set_show_commands add_setshow_boolean_cmd(const char *name, enum command_class theclass, bool *var, const char *set_doc, const char *show_doc, const char *help_doc, cmd_func_ftype *set_func, show_value_ftype *show_func, struct cmd_list_element **set_list, struct cmd_list_element **show_list)
Definition cli-decode.c:809
@ class_support
Definition command.h:58
void elfctf_build_psymtabs(struct objfile *of)
Definition ctfread.c:1638
void elfstab_build_psymtabs(struct objfile *objfile, asection *stabsect, file_ptr stabstroffset, unsigned int stabstrsize)
Definition dbxread.c:3078
scoped_fd debuginfod_debuginfo_query(const unsigned char *build_id, int build_id_len, const char *filename, gdb::unique_xmalloc_ptr< char > *destname)
CORE_ADDR extract_typed_address(const gdb_byte *buf, struct type *type)
Definition findvar.c:152
@ lval_memory
Definition defs.h:363
std::vector< std::unique_ptr< probe > > elfread_data
Definition elfread.c:71
static void elf_gnu_ifunc_resolver_stop(code_breakpoint *b)
Definition elfread.c:956
#define ST_DYNAMIC
Definition elfread.c:238
static const registry< bfd >::key< elfread_data > probe_key
Definition elfread.c:75
static void elf_new_init(struct objfile *ignore)
Definition elfread.c:1380
static void elf_symfile_init(struct objfile *objfile)
Definition elfread.c:1397
static void elf_read_minimal_symbols(struct objfile *objfile, int symfile_flags, const struct elfinfo *ei)
Definition elfread.c:1066
#define ST_SYNTHETIC
Definition elfread.c:239
static bool always_read_ctf
Definition elfread.c:56
#define ST_REGULAR
Definition elfread.c:237
static int elf_gnu_ifunc_cache_eq(const void *a_voidp, const void *b_voidp)
Definition elfread.c:678
static const struct sym_fns elf_sym_fns
Definition elfread.c:1432
static CORE_ADDR elf_gnu_ifunc_resolve_addr(struct gdbarch *gdbarch, CORE_ADDR pc)
Definition elfread.c:910
static const registry< objfile >::key< htab, htab_deleter > elf_objfile_gnu_ifunc_cache_data
Definition elfread.c:652
static symfile_segment_data_up elf_symfile_segments(bfd *abfd)
Definition elfread.c:87
#define SYMBOL_GOT_PLT_SUFFIX
Definition elfread.c:82
static struct minimal_symbol * record_minimal_symbol(minimal_symbol_reader &reader, gdb::string_view name, bool copy_name, unrelocated_addr address, enum minimal_symbol_type ms_type, asection *bfd_section, struct objfile *objfile)
Definition elfread.c:199
void _initialize_elfread()
Definition elfread.c:1457
static int elf_gnu_ifunc_record_cache(const char *name, CORE_ADDR addr)
Definition elfread.c:697
static int elf_gnu_ifunc_resolve_by_cache(const char *name, CORE_ADDR *addr_p)
Definition elfread.c:775
static void elf_symfile_finish(struct objfile *objfile)
Definition elfread.c:1390
static void elf_symtab_read(minimal_symbol_reader &reader, struct objfile *objfile, int type, long number_of_symbols, asymbol **symbol_table, bool copy_names)
Definition elfread.c:242
static void elf_gnu_ifunc_resolver_return_stop(code_breakpoint *b)
Definition elfread.c:1007
static const elfread_data & elf_get_probes(struct objfile *objfile)
Definition elfread.c:1404
static bool elf_symfile_read_dwarf2(struct objfile *objfile, symfile_add_flags symfile_flags)
Definition elfread.c:1198
static hashval_t elf_gnu_ifunc_cache_hash(const void *a_voidp)
Definition elfread.c:667
static void elf_symfile_read(struct objfile *objfile, symfile_add_flags symfile_flags)
Definition elfread.c:1304
static bool elf_gnu_ifunc_resolve_name(const char *name, CORE_ADDR *addr_p)
Definition elfread.c:893
static const struct sym_probe_fns elf_probe_fns
Definition elfread.c:1425
static void elf_rel_plt_read(minimal_symbol_reader &reader, struct objfile *objfile, asymbol **dyn_symbol_table)
Definition elfread.c:549
static void elf_locate_sections(asection *sectp, struct elfinfo *ei)
Definition elfread.c:182
static int elf_gnu_ifunc_resolve_by_got(const char *name, CORE_ADDR *addr_p)
Definition elfread.c:824
static const struct gnu_ifunc_fns elf_gnu_ifunc_fns
Definition elfread.c:1447
CORE_ADDR get_frame_pc(frame_info_ptr frame)
Definition frame.c:2712
struct frame_id get_stack_frame_id(frame_info_ptr next_frame)
Definition frame.c:662
bool frame_id_p(frame_id l)
Definition frame.c:781
struct gdbarch * get_frame_arch(frame_info_ptr this_frame)
Definition frame.c:3027
frame_info_ptr get_current_frame(void)
Definition frame.c:1670
frame_info_ptr get_prev_frame(frame_info_ptr this_frame)
Definition frame.c:2614
int gdb_bfd_section_index(bfd *abfd, asection *section)
Definition gdb_bfd.c:984
gdb::ref_ptr< struct bfd, gdb_bfd_ref_policy > gdb_bfd_ref_ptr
Definition gdb_bfd.h:79
static gdb_bfd_section_range gdb_bfd_sections(bfd *abfd)
Definition gdb_bfd.h:234
bool gdbarch_record_special_symbol_p(struct gdbarch *gdbarch)
Definition gdbarch.c:4468
enum return_value_convention gdbarch_return_value_as_value(struct gdbarch *gdbarch, struct value *function, struct type *valtype, struct regcache *regcache, struct value **read_value, const gdb_byte *writebuf)
Definition gdbarch.c:2610
void gdbarch_iterate_over_objfiles_in_search_order(struct gdbarch *gdbarch, iterate_over_objfiles_in_search_order_cb_ftype cb, struct objfile *current_objfile)
Definition gdbarch.c:5072
void gdbarch_elf_make_msymbol_special(struct gdbarch *gdbarch, asymbol *sym, struct minimal_symbol *msym)
Definition gdbarch.c:3462
bool gdbarch_elf_make_msymbol_special_p(struct gdbarch *gdbarch)
Definition gdbarch.c:3455
void gdbarch_record_special_symbol(struct gdbarch *gdbarch, struct objfile *objfile, asymbol *sym)
Definition gdbarch.c:4475
bfd * obfd
CORE_ADDR gdbarch_addr_bits_remove(struct gdbarch *gdbarch, CORE_ADDR addr)
Definition gdbarch.c:3152
CORE_ADDR gdbarch_convert_from_func_ptr_addr(struct gdbarch *gdbarch, CORE_ADDR addr, struct target_ops *targ)
Definition gdbarch.c:3135
struct thread_info * inferior_thread(void)
Definition thread.c:85
const struct builtin_type * builtin_type(struct gdbarch *gdbarch)
Definition gdbtypes.c:6168
struct value * call_function_by_hand(struct value *function, type *default_return_type, gdb::array_view< value * > args)
Definition infcall.c:824
struct inferior * current_inferior(void)
Definition inferior.c:55
void elfmdebug_build_psymtabs(struct objfile *objfile, const struct ecoff_debug_swap *swap, asection *sec)
struct bound_minimal_symbol lookup_minimal_symbol(const char *name, const char *sfile, struct objfile *objf)
Definition minsyms.c:363
const struct gnu_ifunc_fns * gnu_ifunc_fns_p
Definition minsyms.c:1061
struct bound_minimal_symbol lookup_minimal_symbol_by_pc(CORE_ADDR pc)
Definition minsyms.c:996
@ OBJF_READNEVER
const char * objfile_name(const struct objfile *objfile)
Definition objfiles.c:1259
std::string copy_name(struct stoken token)
Definition parse.c:319
std::vector< const static_probe_ops * > all_static_probe_ops
Definition probe.c:975
struct program_space * current_program_space
Definition progspace.c:40
bool dwarf2_has_info(struct objfile *, const struct dwarf2_debug_sections *, bool=false)
Definition read.c:1360
void dwarf2_initialize_objfile(struct objfile *objfile)
Definition read.c:3383
int value
Definition py-param.c:79
struct regcache * get_thread_regcache(process_stratum_target *target, ptid_t ptid)
Definition regcache.c:400
struct objfile * objfile
Definition minsyms.h:54
CORE_ADDR value_address() const
Definition minsyms.h:41
struct minimal_symbol * minsym
Definition minsyms.h:49
bptype type
Definition breakpoint.h:798
location_spec_up locspec
Definition breakpoint.h:832
breakpoint * related_breakpoint
Definition breakpoint.h:860
bp_location & first_loc()
Definition breakpoint.h:683
bool has_single_location() const
Definition breakpoint.h:665
program_space * pspace
Definition breakpoint.h:829
struct frame_id frame_id
Definition breakpoint.h:824
struct type * builtin_data_ptr
Definition gdbtypes.h:2135
struct type * builtin_func_func
Definition gdbtypes.h:2151
void emit() const
Definition utils.h:416
asection * ctfsect
Definition elfread.c:66
asection * mdebugsect
Definition elfread.c:65
asection * stabsect
Definition elfread.c:64
CORE_ADDR address
Definition symtab.h:561
const char * linkage_name() const
Definition symtab.h:460
unsigned int created_by_gdb
Definition symtab.h:847
unsigned long size() const
Definition symtab.h:784
void set_size(unsigned long size)
Definition symtab.h:791
const char * filename
Definition symtab.h:839
minimal_symbol_type type() const
Definition symtab.h:770
struct objfile * separate_debug_objfile_backlink
Definition objfiles.h:830
struct objfile * separate_debug_objfile
Definition objfiles.h:825
struct gdbarch * arch() const
Definition objfiles.h:507
struct objfile_per_bfd_storage * per_bfd
Definition objfiles.h:744
bool object_format_has_copy_relocs
Definition objfiles.h:884
objfile(gdb_bfd_ref_ptr, const char *, objfile_flags)
Definition objfiles.c:313
gdb_bfd_ref_ptr obfd
Definition objfiles.h:740
const char * intern(const char *str)
Definition objfiles.h:494
objfile_flags flags
Definition objfiles.h:724
auto_obstack objfile_obstack
Definition objfiles.h:760
bool has_partial_symbols()
struct obj_section * section
Definition symtab.h:2330
CORE_ADDR pc
Definition symtab.h:2337
struct program_space * pspace
Definition symtab.h:2326
struct type * target_type() const
Definition gdbtypes.h:1037
ULONGEST length() const
Definition gdbtypes.h:983
Definition value.h:130
static struct value * allocate(struct type *type)
Definition value.c:957
void set_lval(lval_type val)
Definition value.h:336
void set_address(CORE_ADDR)
Definition value.c:1389
CORE_ADDR address
Definition value.h:658
struct obj_section * find_pc_overlay(CORE_ADDR pc)
Definition symfile.c:3174
void add_symtab_fns(enum bfd_flavour flavour, const struct sym_fns *sf)
Definition symfile.c:1804
std::string find_separate_debug_file_by_debuglink(struct objfile *objfile, deferred_warnings *warnings)
Definition symfile.c:1534
void default_symfile_offsets(struct objfile *objfile, const section_addr_info &addrs)
Definition symfile.c:625
void symbol_file_add_separate(const gdb_bfd_ref_ptr &bfd, const char *name, symfile_add_flags symfile_flags, struct objfile *objfile)
Definition symfile.c:1134
gdb_bfd_ref_ptr symfile_bfd_open_no_error(const char *name) noexcept
Definition symfile.c:1769
bfd_byte * default_symfile_relocate(struct objfile *objfile, asection *sectp, bfd_byte *buf)
Definition symfile.c:3595
std::unique_ptr< symfile_segment_data > symfile_segment_data_up
Definition symfile.h:104
symtab_and_line find_function_start_sal(CORE_ADDR func_addr, obj_section *section, bool funfirstline)
Definition symtab.c:3639
minimal_symbol_type
Definition symtab.h:670
@ mst_data_gnu_ifunc
Definition symtab.h:690
@ mst_abs
Definition symtab.h:696
@ mst_bss
Definition symtab.h:695
@ mst_data
Definition symtab.h:694
@ mst_unknown
Definition symtab.h:671
@ mst_solib_trampoline
Definition symtab.h:705
@ mst_file_text
Definition symtab.h:708
@ mst_slot_got_plt
Definition symtab.h:693
@ mst_file_data
Definition symtab.h:709
@ mst_text
Definition symtab.h:672
@ mst_text_gnu_ifunc
Definition symtab.h:681
@ mst_file_bss
Definition symtab.h:710
#define symtab_create_debug_printf(fmt,...)
Definition symtab.h:2683
int target_read_memory(CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len)
Definition target.c:1785
const char * paddress(struct gdbarch *gdbarch, CORE_ADDR addr)
Definition utils.c:3166
CORE_ADDR value_as_address(struct value *val)
Definition value.c:2636
struct value * value_from_longest(struct type *type, LONGEST num)
Definition value.c:3438
const char target_name[]
Definition version.c:4