1 /* Read ELF (Executable and Linking Format) object files for GDB.
3 Copyright (C) 1991-2013 Free Software Foundation, Inc.
5 Written by Fred Fish at Cygnus Support.
7 This file is part of GDB.
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.
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.
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/>. */
24 #include "gdb_string.h"
26 #include "elf/common.h"
27 #include "elf/internal.h"
33 #include "stabsread.h"
34 #include "gdb-stabs.h"
35 #include "complaints.h"
38 #include "filenames.h"
40 #include "arch-utils.h"
44 #include "gdbthread.h"
49 extern void _initialize_elfread (void);
51 /* Forward declarations. */
52 static const struct sym_fns elf_sym_fns_gdb_index;
53 static const struct sym_fns elf_sym_fns_lazy_psyms;
55 /* The struct elfinfo is available only during ELF symbol table and
56 psymtab reading. It is destroyed at the completion of psymtab-reading.
57 It's local to elf_symfile_read. */
61 asection *stabsect; /* Section pointer for .stab section */
62 asection *stabindexsect; /* Section pointer for .stab.index section */
63 asection *mdebugsect; /* Section pointer for .mdebug section */
66 /* Per-objfile data for probe info. */
68 static const struct objfile_data *probe_key = NULL;
70 static void free_elfinfo (void *);
72 /* Minimal symbols located at the GOT entries for .plt - that is the real
73 pointer where the given entry will jump to. It gets updated by the real
74 function address during lazy ld.so resolving in the inferior. These
75 minimal symbols are indexed for <tab>-completion. */
77 #define SYMBOL_GOT_PLT_SUFFIX "@got.plt"
79 /* Locate the segments in ABFD. */
81 static struct symfile_segment_data *
82 elf_symfile_segments (bfd *abfd)
84 Elf_Internal_Phdr *phdrs, **segments;
86 int num_phdrs, num_segments, num_sections, i;
88 struct symfile_segment_data *data;
90 phdrs_size = bfd_get_elf_phdr_upper_bound (abfd);
94 phdrs = alloca (phdrs_size);
95 num_phdrs = bfd_get_elf_phdrs (abfd, phdrs);
100 segments = alloca (sizeof (Elf_Internal_Phdr *) * num_phdrs);
101 for (i = 0; i < num_phdrs; i++)
102 if (phdrs[i].p_type == PT_LOAD)
103 segments[num_segments++] = &phdrs[i];
105 if (num_segments == 0)
108 data = XZALLOC (struct symfile_segment_data);
109 data->num_segments = num_segments;
110 data->segment_bases = XCALLOC (num_segments, CORE_ADDR);
111 data->segment_sizes = XCALLOC (num_segments, CORE_ADDR);
113 for (i = 0; i < num_segments; i++)
115 data->segment_bases[i] = segments[i]->p_vaddr;
116 data->segment_sizes[i] = segments[i]->p_memsz;
119 num_sections = bfd_count_sections (abfd);
120 data->segment_info = XCALLOC (num_sections, int);
122 for (i = 0, sect = abfd->sections; sect != NULL; i++, sect = sect->next)
127 if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
130 vma = bfd_get_section_vma (abfd, sect);
132 for (j = 0; j < num_segments; j++)
133 if (segments[j]->p_memsz > 0
134 && vma >= segments[j]->p_vaddr
135 && (vma - segments[j]->p_vaddr) < segments[j]->p_memsz)
137 data->segment_info[i] = j + 1;
141 /* We should have found a segment for every non-empty section.
142 If we haven't, we will not relocate this section by any
143 offsets we apply to the segments. As an exception, do not
144 warn about SHT_NOBITS sections; in normal ELF execution
145 environments, SHT_NOBITS means zero-initialized and belongs
146 in a segment, but in no-OS environments some tools (e.g. ARM
147 RealView) use SHT_NOBITS for uninitialized data. Since it is
148 uninitialized, it doesn't need a program header. Such
149 binaries are not relocatable. */
150 if (bfd_get_section_size (sect) > 0 && j == num_segments
151 && (bfd_get_section_flags (abfd, sect) & SEC_LOAD) != 0)
152 warning (_("Loadable section \"%s\" outside of ELF segments"),
153 bfd_section_name (abfd, sect));
159 /* We are called once per section from elf_symfile_read. We
160 need to examine each section we are passed, check to see
161 if it is something we are interested in processing, and
162 if so, stash away some access information for the section.
164 For now we recognize the dwarf debug information sections and
165 line number sections from matching their section names. The
166 ELF definition is no real help here since it has no direct
167 knowledge of DWARF (by design, so any debugging format can be
170 We also recognize the ".stab" sections used by the Sun compilers
171 released with Solaris 2.
173 FIXME: The section names should not be hardwired strings (what
174 should they be? I don't think most object file formats have enough
175 section flags to specify what kind of debug section it is.
179 elf_locate_sections (bfd *ignore_abfd, asection *sectp, void *eip)
183 ei = (struct elfinfo *) eip;
184 if (strcmp (sectp->name, ".stab") == 0)
186 ei->stabsect = sectp;
188 else if (strcmp (sectp->name, ".stab.index") == 0)
190 ei->stabindexsect = sectp;
192 else if (strcmp (sectp->name, ".mdebug") == 0)
194 ei->mdebugsect = sectp;
198 static struct minimal_symbol *
199 record_minimal_symbol (const char *name, int name_len, int copy_name,
201 enum minimal_symbol_type ms_type,
202 asection *bfd_section, struct objfile *objfile)
204 struct gdbarch *gdbarch = get_objfile_arch (objfile);
206 if (ms_type == mst_text || ms_type == mst_file_text
207 || ms_type == mst_text_gnu_ifunc)
208 address = gdbarch_addr_bits_remove (gdbarch, address);
210 return prim_record_minimal_symbol_full (name, name_len, copy_name, address,
211 ms_type, bfd_section->index,
212 bfd_section, objfile);
215 /* Read the symbol table of an ELF file.
217 Given an objfile, a symbol table, and a flag indicating whether the
218 symbol table contains regular, dynamic, or synthetic symbols, add all
219 the global function and data symbols to the minimal symbol table.
221 In stabs-in-ELF, as implemented by Sun, there are some local symbols
222 defined in the ELF symbol table, which can be used to locate
223 the beginnings of sections from each ".o" file that was linked to
224 form the executable objfile. We gather any such info and record it
225 in data structures hung off the objfile's private data. */
229 #define ST_SYNTHETIC 2
232 elf_symtab_read (struct objfile *objfile, int type,
233 long number_of_symbols, asymbol **symbol_table,
236 struct gdbarch *gdbarch = get_objfile_arch (objfile);
241 enum minimal_symbol_type ms_type;
242 /* If sectinfo is nonNULL, it contains section info that should end up
243 filed in the objfile. */
244 struct stab_section_info *sectinfo = NULL;
245 /* If filesym is nonzero, it points to a file symbol, but we haven't
246 seen any section info for it yet. */
247 asymbol *filesym = 0;
248 /* Name of filesym. This is either a constant string or is saved on
249 the objfile's filename cache. */
250 const char *filesymname = "";
251 struct dbx_symfile_info *dbx = DBX_SYMFILE_INFO (objfile);
252 int stripped = (bfd_get_symcount (objfile->obfd) == 0);
254 for (i = 0; i < number_of_symbols; i++)
256 sym = symbol_table[i];
257 if (sym->name == NULL || *sym->name == '\0')
259 /* Skip names that don't exist (shouldn't happen), or names
260 that are null strings (may happen). */
264 /* Skip "special" symbols, e.g. ARM mapping symbols. These are
265 symbols which do not correspond to objects in the symbol table,
266 but have some other target-specific meaning. */
267 if (bfd_is_target_special_symbol (objfile->obfd, sym))
269 if (gdbarch_record_special_symbol_p (gdbarch))
270 gdbarch_record_special_symbol (gdbarch, objfile, sym);
274 offset = ANOFFSET (objfile->section_offsets, sym->section->index);
275 if (type == ST_DYNAMIC
276 && sym->section == bfd_und_section_ptr
277 && (sym->flags & BSF_FUNCTION))
279 struct minimal_symbol *msym;
280 bfd *abfd = objfile->obfd;
283 /* Symbol is a reference to a function defined in
285 If its value is non zero then it is usually the address
286 of the corresponding entry in the procedure linkage table,
287 plus the desired section offset.
288 If its value is zero then the dynamic linker has to resolve
289 the symbol. We are unable to find any meaningful address
290 for this symbol in the executable file, so we skip it. */
291 symaddr = sym->value;
295 /* sym->section is the undefined section. However, we want to
296 record the section where the PLT stub resides with the
297 minimal symbol. Search the section table for the one that
298 covers the stub's address. */
299 for (sect = abfd->sections; sect != NULL; sect = sect->next)
301 if ((bfd_get_section_flags (abfd, sect) & SEC_ALLOC) == 0)
304 if (symaddr >= bfd_get_section_vma (abfd, sect)
305 && symaddr < bfd_get_section_vma (abfd, sect)
306 + bfd_get_section_size (sect))
312 /* On ia64-hpux, we have discovered that the system linker
313 adds undefined symbols with nonzero addresses that cannot
314 be right (their address points inside the code of another
315 function in the .text section). This creates problems
316 when trying to determine which symbol corresponds to
319 We try to detect those buggy symbols by checking which
320 section we think they correspond to. Normally, PLT symbols
321 are stored inside their own section, and the typical name
322 for that section is ".plt". So, if there is a ".plt"
323 section, and yet the section name of our symbol does not
324 start with ".plt", we ignore that symbol. */
325 if (strncmp (sect->name, ".plt", 4) != 0
326 && bfd_get_section_by_name (abfd, ".plt") != NULL)
329 symaddr += ANOFFSET (objfile->section_offsets, sect->index);
331 msym = record_minimal_symbol
332 (sym->name, strlen (sym->name), copy_names,
333 symaddr, mst_solib_trampoline, sect, objfile);
335 msym->filename = filesymname;
339 /* If it is a nonstripped executable, do not enter dynamic
340 symbols, as the dynamic symbol table is usually a subset
341 of the main symbol table. */
342 if (type == ST_DYNAMIC && !stripped)
344 if (sym->flags & BSF_FILE)
346 /* STT_FILE debugging symbol that helps stabs-in-elf debugging.
347 Chain any old one onto the objfile; remember new sym. */
348 if (sectinfo != NULL)
350 sectinfo->next = dbx->stab_section_info;
351 dbx->stab_section_info = sectinfo;
355 filesymname = bcache (filesym->name, strlen (filesym->name) + 1,
356 objfile->per_bfd->filename_cache);
358 else if (sym->flags & BSF_SECTION_SYM)
360 else if (sym->flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
362 struct minimal_symbol *msym;
364 /* Select global/local/weak symbols. Note that bfd puts abs
365 symbols in their own section, so all symbols we are
366 interested in will have a section. */
367 /* Bfd symbols are section relative. */
368 symaddr = sym->value + sym->section->vma;
369 /* Relocate all non-absolute and non-TLS symbols by the
371 if (sym->section != bfd_abs_section_ptr
372 && !(sym->section->flags & SEC_THREAD_LOCAL))
376 /* For non-absolute symbols, use the type of the section
377 they are relative to, to intuit text/data. Bfd provides
378 no way of figuring this out for absolute symbols. */
379 if (sym->section == bfd_abs_section_ptr)
381 /* This is a hack to get the minimal symbol type
382 right for Irix 5, which has absolute addresses
383 with special section indices for dynamic symbols.
385 NOTE: uweigand-20071112: Synthetic symbols do not
386 have an ELF-private part, so do not touch those. */
387 unsigned int shndx = type == ST_SYNTHETIC ? 0 :
388 ((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
398 case SHN_MIPS_ACOMMON:
405 /* If it is an Irix dynamic symbol, skip section name
406 symbols, relocate all others by section offset. */
407 if (ms_type != mst_abs)
409 if (sym->name[0] == '.')
414 else if (sym->section->flags & SEC_CODE)
416 if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
418 if (sym->flags & BSF_GNU_INDIRECT_FUNCTION)
419 ms_type = mst_text_gnu_ifunc;
423 /* The BSF_SYNTHETIC check is there to omit ppc64 function
424 descriptors mistaken for static functions starting with 'L'.
426 else if ((sym->name[0] == '.' && sym->name[1] == 'L'
427 && (sym->flags & BSF_SYNTHETIC) == 0)
428 || ((sym->flags & BSF_LOCAL)
429 && sym->name[0] == '$'
430 && sym->name[1] == 'L'))
431 /* Looks like a compiler-generated label. Skip
432 it. The assembler should be skipping these (to
433 keep executables small), but apparently with
434 gcc on the (deleted) delta m88k SVR4, it loses.
435 So to have us check too should be harmless (but
436 I encourage people to fix this in the assembler
437 instead of adding checks here). */
441 ms_type = mst_file_text;
444 else if (sym->section->flags & SEC_ALLOC)
446 if (sym->flags & (BSF_GLOBAL | BSF_WEAK))
448 if (sym->section->flags & SEC_LOAD)
457 else if (sym->flags & BSF_LOCAL)
459 /* Named Local variable in a Data section.
460 Check its name for stabs-in-elf. */
461 int special_local_sect;
463 if (strcmp ("Bbss.bss", sym->name) == 0)
464 special_local_sect = SECT_OFF_BSS (objfile);
465 else if (strcmp ("Ddata.data", sym->name) == 0)
466 special_local_sect = SECT_OFF_DATA (objfile);
467 else if (strcmp ("Drodata.rodata", sym->name) == 0)
468 special_local_sect = SECT_OFF_RODATA (objfile);
470 special_local_sect = -1;
471 if (special_local_sect >= 0)
473 /* Found a special local symbol. Allocate a
474 sectinfo, if needed, and fill it in. */
475 if (sectinfo == NULL)
480 max_index = SECT_OFF_BSS (objfile);
481 if (objfile->sect_index_data > max_index)
482 max_index = objfile->sect_index_data;
483 if (objfile->sect_index_rodata > max_index)
484 max_index = objfile->sect_index_rodata;
486 /* max_index is the largest index we'll
487 use into this array, so we must
488 allocate max_index+1 elements for it.
489 However, 'struct stab_section_info'
490 already includes one element, so we
491 need to allocate max_index aadditional
493 size = (sizeof (struct stab_section_info)
494 + (sizeof (CORE_ADDR) * max_index));
495 sectinfo = (struct stab_section_info *)
497 memset (sectinfo, 0, size);
498 sectinfo->num_sections = max_index;
501 complaint (&symfile_complaints,
502 _("elf/stab section information %s "
503 "without a preceding file symbol"),
509 (char *) filesym->name;
512 if (sectinfo->sections[special_local_sect] != 0)
513 complaint (&symfile_complaints,
514 _("duplicated elf/stab section "
515 "information for %s"),
517 /* BFD symbols are section relative. */
518 symaddr = sym->value + sym->section->vma;
519 /* Relocate non-absolute symbols by the
521 if (sym->section != bfd_abs_section_ptr)
523 sectinfo->sections[special_local_sect] = symaddr;
524 /* The special local symbols don't go in the
525 minimal symbol table, so ignore this one. */
528 /* Not a special stabs-in-elf symbol, do regular
529 symbol processing. */
530 if (sym->section->flags & SEC_LOAD)
532 ms_type = mst_file_data;
536 ms_type = mst_file_bss;
541 ms_type = mst_unknown;
546 /* FIXME: Solaris2 shared libraries include lots of
547 odd "absolute" and "undefined" symbols, that play
548 hob with actions like finding what function the PC
549 is in. Ignore them if they aren't text, data, or bss. */
550 /* ms_type = mst_unknown; */
551 continue; /* Skip this symbol. */
553 msym = record_minimal_symbol
554 (sym->name, strlen (sym->name), copy_names, symaddr,
555 ms_type, sym->section, objfile);
559 /* Pass symbol size field in via BFD. FIXME!!! */
560 elf_symbol_type *elf_sym;
562 /* NOTE: uweigand-20071112: A synthetic symbol does not have an
563 ELF-private part. However, in some cases (e.g. synthetic
564 'dot' symbols on ppc64) the udata.p entry is set to point back
565 to the original ELF symbol it was derived from. Get the size
567 if (type != ST_SYNTHETIC)
568 elf_sym = (elf_symbol_type *) sym;
570 elf_sym = (elf_symbol_type *) sym->udata.p;
573 SET_MSYMBOL_SIZE (msym, elf_sym->internal_elf_sym.st_size);
575 msym->filename = filesymname;
576 gdbarch_elf_make_msymbol_special (gdbarch, sym, msym);
579 /* For @plt symbols, also record a trampoline to the
580 destination symbol. The @plt symbol will be used in
581 disassembly, and the trampoline will be used when we are
582 trying to find the target. */
583 if (msym && ms_type == mst_text && type == ST_SYNTHETIC)
585 int len = strlen (sym->name);
587 if (len > 4 && strcmp (sym->name + len - 4, "@plt") == 0)
589 struct minimal_symbol *mtramp;
591 mtramp = record_minimal_symbol (sym->name, len - 4, 1,
593 mst_solib_trampoline,
594 sym->section, objfile);
597 SET_MSYMBOL_SIZE (mtramp, MSYMBOL_SIZE (msym));
598 mtramp->created_by_gdb = 1;
599 mtramp->filename = filesymname;
600 gdbarch_elf_make_msymbol_special (gdbarch, sym, mtramp);
608 /* Build minimal symbols named `function@got.plt' (see SYMBOL_GOT_PLT_SUFFIX)
609 for later look ups of which function to call when user requests
610 a STT_GNU_IFUNC function. As the STT_GNU_IFUNC type is found at the target
611 library defining `function' we cannot yet know while reading OBJFILE which
612 of the SYMBOL_GOT_PLT_SUFFIX entries will be needed and later
613 DYN_SYMBOL_TABLE is no longer easily available for OBJFILE. */
616 elf_rel_plt_read (struct objfile *objfile, asymbol **dyn_symbol_table)
618 bfd *obfd = objfile->obfd;
619 const struct elf_backend_data *bed = get_elf_backend_data (obfd);
620 asection *plt, *relplt, *got_plt;
622 bfd_size_type reloc_count, reloc;
623 char *string_buffer = NULL;
624 size_t string_buffer_size = 0;
625 struct cleanup *back_to;
626 struct gdbarch *gdbarch = objfile->gdbarch;
627 struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
628 size_t ptr_size = TYPE_LENGTH (ptr_type);
630 if (objfile->separate_debug_objfile_backlink)
633 plt = bfd_get_section_by_name (obfd, ".plt");
636 plt_elf_idx = elf_section_data (plt)->this_idx;
638 got_plt = bfd_get_section_by_name (obfd, ".got.plt");
642 /* This search algorithm is from _bfd_elf_canonicalize_dynamic_reloc. */
643 for (relplt = obfd->sections; relplt != NULL; relplt = relplt->next)
644 if (elf_section_data (relplt)->this_hdr.sh_info == plt_elf_idx
645 && (elf_section_data (relplt)->this_hdr.sh_type == SHT_REL
646 || elf_section_data (relplt)->this_hdr.sh_type == SHT_RELA))
651 if (! bed->s->slurp_reloc_table (obfd, relplt, dyn_symbol_table, TRUE))
654 back_to = make_cleanup (free_current_contents, &string_buffer);
656 reloc_count = relplt->size / elf_section_data (relplt)->this_hdr.sh_entsize;
657 for (reloc = 0; reloc < reloc_count; reloc++)
660 struct minimal_symbol *msym;
662 const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
665 name = bfd_asymbol_name (*relplt->relocation[reloc].sym_ptr_ptr);
666 name_len = strlen (name);
667 address = relplt->relocation[reloc].address;
669 /* Does the pointer reside in the .got.plt section? */
670 if (!(bfd_get_section_vma (obfd, got_plt) <= address
671 && address < bfd_get_section_vma (obfd, got_plt)
672 + bfd_get_section_size (got_plt)))
675 /* We cannot check if NAME is a reference to mst_text_gnu_ifunc as in
676 OBJFILE the symbol is undefined and the objfile having NAME defined
677 may not yet have been loaded. */
679 if (string_buffer_size < name_len + got_suffix_len + 1)
681 string_buffer_size = 2 * (name_len + got_suffix_len);
682 string_buffer = xrealloc (string_buffer, string_buffer_size);
684 memcpy (string_buffer, name, name_len);
685 memcpy (&string_buffer[name_len], SYMBOL_GOT_PLT_SUFFIX,
688 msym = record_minimal_symbol (string_buffer, name_len + got_suffix_len,
689 1, address, mst_slot_got_plt, got_plt,
692 SET_MSYMBOL_SIZE (msym, ptr_size);
695 do_cleanups (back_to);
698 /* The data pointer is htab_t for gnu_ifunc_record_cache_unchecked. */
700 static const struct objfile_data *elf_objfile_gnu_ifunc_cache_data;
702 /* Map function names to CORE_ADDR in elf_objfile_gnu_ifunc_cache_data. */
704 struct elf_gnu_ifunc_cache
706 /* This is always a function entry address, not a function descriptor. */
712 /* htab_hash for elf_objfile_gnu_ifunc_cache_data. */
715 elf_gnu_ifunc_cache_hash (const void *a_voidp)
717 const struct elf_gnu_ifunc_cache *a = a_voidp;
719 return htab_hash_string (a->name);
722 /* htab_eq for elf_objfile_gnu_ifunc_cache_data. */
725 elf_gnu_ifunc_cache_eq (const void *a_voidp, const void *b_voidp)
727 const struct elf_gnu_ifunc_cache *a = a_voidp;
728 const struct elf_gnu_ifunc_cache *b = b_voidp;
730 return strcmp (a->name, b->name) == 0;
733 /* Record the target function address of a STT_GNU_IFUNC function NAME is the
734 function entry address ADDR. Return 1 if NAME and ADDR are considered as
735 valid and therefore they were successfully recorded, return 0 otherwise.
737 Function does not expect a duplicate entry. Use
738 elf_gnu_ifunc_resolve_by_cache first to check if the entry for NAME already
742 elf_gnu_ifunc_record_cache (const char *name, CORE_ADDR addr)
744 struct minimal_symbol *msym;
746 struct objfile *objfile;
748 struct elf_gnu_ifunc_cache entry_local, *entry_p;
751 msym = lookup_minimal_symbol_by_pc (addr);
754 if (SYMBOL_VALUE_ADDRESS (msym) != addr)
756 /* minimal symbols have always SYMBOL_OBJ_SECTION non-NULL. */
757 sect = SYMBOL_OBJ_SECTION (msym)->the_bfd_section;
758 objfile = SYMBOL_OBJ_SECTION (msym)->objfile;
760 /* If .plt jumps back to .plt the symbol is still deferred for later
761 resolution and it has no use for GDB. Besides ".text" this symbol can
762 reside also in ".opd" for ppc64 function descriptor. */
763 if (strcmp (bfd_get_section_name (objfile->obfd, sect), ".plt") == 0)
766 htab = objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data);
769 htab = htab_create_alloc_ex (1, elf_gnu_ifunc_cache_hash,
770 elf_gnu_ifunc_cache_eq,
771 NULL, &objfile->objfile_obstack,
772 hashtab_obstack_allocate,
773 dummy_obstack_deallocate);
774 set_objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data, htab);
777 entry_local.addr = addr;
778 obstack_grow (&objfile->objfile_obstack, &entry_local,
779 offsetof (struct elf_gnu_ifunc_cache, name));
780 obstack_grow_str0 (&objfile->objfile_obstack, name);
781 entry_p = obstack_finish (&objfile->objfile_obstack);
783 slot = htab_find_slot (htab, entry_p, INSERT);
786 struct elf_gnu_ifunc_cache *entry_found_p = *slot;
787 struct gdbarch *gdbarch = objfile->gdbarch;
789 if (entry_found_p->addr != addr)
791 /* This case indicates buggy inferior program, the resolved address
792 should never change. */
794 warning (_("gnu-indirect-function \"%s\" has changed its resolved "
795 "function_address from %s to %s"),
796 name, paddress (gdbarch, entry_found_p->addr),
797 paddress (gdbarch, addr));
800 /* New ENTRY_P is here leaked/duplicate in the OBJFILE obstack. */
807 /* Try to find the target resolved function entry address of a STT_GNU_IFUNC
808 function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
809 is not NULL) and the function returns 1. It returns 0 otherwise.
811 Only the elf_objfile_gnu_ifunc_cache_data hash table is searched by this
815 elf_gnu_ifunc_resolve_by_cache (const char *name, CORE_ADDR *addr_p)
817 struct objfile *objfile;
819 ALL_PSPACE_OBJFILES (current_program_space, objfile)
822 struct elf_gnu_ifunc_cache *entry_p;
825 htab = objfile_data (objfile, elf_objfile_gnu_ifunc_cache_data);
829 entry_p = alloca (sizeof (*entry_p) + strlen (name));
830 strcpy (entry_p->name, name);
832 slot = htab_find_slot (htab, entry_p, NO_INSERT);
836 gdb_assert (entry_p != NULL);
839 *addr_p = entry_p->addr;
846 /* Try to find the target resolved function entry address of a STT_GNU_IFUNC
847 function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
848 is not NULL) and the function returns 1. It returns 0 otherwise.
850 Only the SYMBOL_GOT_PLT_SUFFIX locations are searched by this function.
851 elf_gnu_ifunc_resolve_by_cache must have been already called for NAME to
852 prevent cache entries duplicates. */
855 elf_gnu_ifunc_resolve_by_got (const char *name, CORE_ADDR *addr_p)
858 struct objfile *objfile;
859 const size_t got_suffix_len = strlen (SYMBOL_GOT_PLT_SUFFIX);
861 name_got_plt = alloca (strlen (name) + got_suffix_len + 1);
862 sprintf (name_got_plt, "%s" SYMBOL_GOT_PLT_SUFFIX, name);
864 ALL_PSPACE_OBJFILES (current_program_space, objfile)
866 bfd *obfd = objfile->obfd;
867 struct gdbarch *gdbarch = objfile->gdbarch;
868 struct type *ptr_type = builtin_type (gdbarch)->builtin_data_ptr;
869 size_t ptr_size = TYPE_LENGTH (ptr_type);
870 CORE_ADDR pointer_address, addr;
872 gdb_byte *buf = alloca (ptr_size);
873 struct minimal_symbol *msym;
875 msym = lookup_minimal_symbol (name_got_plt, NULL, objfile);
878 if (MSYMBOL_TYPE (msym) != mst_slot_got_plt)
880 pointer_address = SYMBOL_VALUE_ADDRESS (msym);
882 plt = bfd_get_section_by_name (obfd, ".plt");
886 if (MSYMBOL_SIZE (msym) != ptr_size)
888 if (target_read_memory (pointer_address, buf, ptr_size) != 0)
890 addr = extract_typed_address (buf, ptr_type);
891 addr = gdbarch_convert_from_func_ptr_addr (gdbarch, addr,
896 if (elf_gnu_ifunc_record_cache (name, addr))
903 /* Try to find the target resolved function entry address of a STT_GNU_IFUNC
904 function NAME. If the address is found it is stored to *ADDR_P (if ADDR_P
905 is not NULL) and the function returns 1. It returns 0 otherwise.
907 Both the elf_objfile_gnu_ifunc_cache_data hash table and
908 SYMBOL_GOT_PLT_SUFFIX locations are searched by this function. */
911 elf_gnu_ifunc_resolve_name (const char *name, CORE_ADDR *addr_p)
913 if (elf_gnu_ifunc_resolve_by_cache (name, addr_p))
916 if (elf_gnu_ifunc_resolve_by_got (name, addr_p))
922 /* Call STT_GNU_IFUNC - a function returning addresss of a real function to
923 call. PC is theSTT_GNU_IFUNC resolving function entry. The value returned
924 is the entry point of the resolved STT_GNU_IFUNC target function to call.
928 elf_gnu_ifunc_resolve_addr (struct gdbarch *gdbarch, CORE_ADDR pc)
930 const char *name_at_pc;
931 CORE_ADDR start_at_pc, address;
932 struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
933 struct value *function, *address_val;
935 /* Try first any non-intrusive methods without an inferior call. */
937 if (find_pc_partial_function (pc, &name_at_pc, &start_at_pc, NULL)
938 && start_at_pc == pc)
940 if (elf_gnu_ifunc_resolve_name (name_at_pc, &address))
946 function = allocate_value (func_func_type);
947 set_value_address (function, pc);
949 /* STT_GNU_IFUNC resolver functions have no parameters. FUNCTION is the
950 function entry address. ADDRESS may be a function descriptor. */
952 address_val = call_function_by_hand (function, 0, NULL);
953 address = value_as_address (address_val);
954 address = gdbarch_convert_from_func_ptr_addr (gdbarch, address,
958 elf_gnu_ifunc_record_cache (name_at_pc, address);
963 /* Handle inferior hit of bp_gnu_ifunc_resolver, see its definition. */
966 elf_gnu_ifunc_resolver_stop (struct breakpoint *b)
968 struct breakpoint *b_return;
969 struct frame_info *prev_frame = get_prev_frame (get_current_frame ());
970 struct frame_id prev_frame_id = get_stack_frame_id (prev_frame);
971 CORE_ADDR prev_pc = get_frame_pc (prev_frame);
972 int thread_id = pid_to_thread_id (inferior_ptid);
974 gdb_assert (b->type == bp_gnu_ifunc_resolver);
976 for (b_return = b->related_breakpoint; b_return != b;
977 b_return = b_return->related_breakpoint)
979 gdb_assert (b_return->type == bp_gnu_ifunc_resolver_return);
980 gdb_assert (b_return->loc != NULL && b_return->loc->next == NULL);
981 gdb_assert (frame_id_p (b_return->frame_id));
983 if (b_return->thread == thread_id
984 && b_return->loc->requested_address == prev_pc
985 && frame_id_eq (b_return->frame_id, prev_frame_id))
991 struct symtab_and_line sal;
993 /* No need to call find_pc_line for symbols resolving as this is only
994 a helper breakpointer never shown to the user. */
997 sal.pspace = current_inferior ()->pspace;
999 sal.section = find_pc_overlay (sal.pc);
1000 sal.explicit_pc = 1;
1001 b_return = set_momentary_breakpoint (get_frame_arch (prev_frame), sal,
1003 bp_gnu_ifunc_resolver_return);
1005 /* set_momentary_breakpoint invalidates PREV_FRAME. */
1008 /* Add new b_return to the ring list b->related_breakpoint. */
1009 gdb_assert (b_return->related_breakpoint == b_return);
1010 b_return->related_breakpoint = b->related_breakpoint;
1011 b->related_breakpoint = b_return;
1015 /* Handle inferior hit of bp_gnu_ifunc_resolver_return, see its definition. */
1018 elf_gnu_ifunc_resolver_return_stop (struct breakpoint *b)
1020 struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
1021 struct type *func_func_type = builtin_type (gdbarch)->builtin_func_func;
1022 struct type *value_type = TYPE_TARGET_TYPE (func_func_type);
1023 struct regcache *regcache = get_thread_regcache (inferior_ptid);
1024 struct value *func_func;
1025 struct value *value;
1026 CORE_ADDR resolved_address, resolved_pc;
1027 struct symtab_and_line sal;
1028 struct symtabs_and_lines sals, sals_end;
1030 gdb_assert (b->type == bp_gnu_ifunc_resolver_return);
1032 while (b->related_breakpoint != b)
1034 struct breakpoint *b_next = b->related_breakpoint;
1038 case bp_gnu_ifunc_resolver:
1040 case bp_gnu_ifunc_resolver_return:
1041 delete_breakpoint (b);
1044 internal_error (__FILE__, __LINE__,
1045 _("handle_inferior_event: Invalid "
1046 "gnu-indirect-function breakpoint type %d"),
1051 gdb_assert (b->type == bp_gnu_ifunc_resolver);
1052 gdb_assert (b->loc->next == NULL);
1054 func_func = allocate_value (func_func_type);
1055 set_value_address (func_func, b->loc->related_address);
1057 value = allocate_value (value_type);
1058 gdbarch_return_value (gdbarch, func_func, value_type, regcache,
1059 value_contents_raw (value), NULL);
1060 resolved_address = value_as_address (value);
1061 resolved_pc = gdbarch_convert_from_func_ptr_addr (gdbarch,
1065 gdb_assert (current_program_space == b->pspace || b->pspace == NULL);
1066 elf_gnu_ifunc_record_cache (b->addr_string, resolved_pc);
1068 sal = find_pc_line (resolved_pc, 0);
1073 b->type = bp_breakpoint;
1074 update_breakpoint_locations (b, sals, sals_end);
1077 /* Locate NT_GNU_BUILD_ID from ABFD and return its content. */
1079 static const struct elf_build_id *
1080 build_id_bfd_get (bfd *abfd)
1082 if (!bfd_check_format (abfd, bfd_object)
1083 || bfd_get_flavour (abfd) != bfd_target_elf_flavour
1084 || elf_tdata (abfd)->build_id == NULL)
1087 return elf_tdata (abfd)->build_id;
1090 /* Return if FILENAME has NT_GNU_BUILD_ID matching the CHECK value. */
1093 build_id_verify (const char *filename, const struct elf_build_id *check)
1096 const struct elf_build_id *found;
1099 /* We expect to be silent on the non-existing files. */
1100 abfd = gdb_bfd_open_maybe_remote (filename);
1104 found = build_id_bfd_get (abfd);
1107 warning (_("File \"%s\" has no build-id, file skipped"), filename);
1108 else if (found->size != check->size
1109 || memcmp (found->data, check->data, found->size) != 0)
1110 warning (_("File \"%s\" has a different build-id, file skipped"),
1115 gdb_bfd_unref (abfd);
1121 build_id_to_debug_filename (const struct elf_build_id *build_id)
1123 char *link, *debugdir, *retval = NULL;
1124 VEC (char_ptr) *debugdir_vec;
1125 struct cleanup *back_to;
1128 /* DEBUG_FILE_DIRECTORY/.build-id/ab/cdef */
1129 link = alloca (strlen (debug_file_directory) + (sizeof "/.build-id/" - 1) + 1
1130 + 2 * build_id->size + (sizeof ".debug" - 1) + 1);
1132 /* Keep backward compatibility so that DEBUG_FILE_DIRECTORY being "" will
1133 cause "/.build-id/..." lookups. */
1135 debugdir_vec = dirnames_to_char_ptr_vec (debug_file_directory);
1136 back_to = make_cleanup_free_char_ptr_vec (debugdir_vec);
1138 for (ix = 0; VEC_iterate (char_ptr, debugdir_vec, ix, debugdir); ++ix)
1140 size_t debugdir_len = strlen (debugdir);
1141 const gdb_byte *data = build_id->data;
1142 size_t size = build_id->size;
1145 memcpy (link, debugdir, debugdir_len);
1146 s = &link[debugdir_len];
1147 s += sprintf (s, "/.build-id/");
1151 s += sprintf (s, "%02x", (unsigned) *data++);
1156 s += sprintf (s, "%02x", (unsigned) *data++);
1157 strcpy (s, ".debug");
1159 /* lrealpath() is expensive even for the usually non-existent files. */
1160 if (access (link, F_OK) == 0)
1161 retval = lrealpath (link);
1163 if (retval != NULL && !build_id_verify (retval, build_id))
1173 do_cleanups (back_to);
1178 find_separate_debug_file_by_buildid (struct objfile *objfile)
1180 const struct elf_build_id *build_id;
1182 build_id = build_id_bfd_get (objfile->obfd);
1183 if (build_id != NULL)
1185 char *build_id_name;
1187 build_id_name = build_id_to_debug_filename (build_id);
1188 /* Prevent looping on a stripped .debug file. */
1189 if (build_id_name != NULL
1190 && filename_cmp (build_id_name, objfile->name) == 0)
1192 warning (_("\"%s\": separate debug info file has no debug info"),
1194 xfree (build_id_name);
1196 else if (build_id_name != NULL)
1197 return build_id_name;
1202 /* Scan and build partial symbols for a symbol file.
1203 We have been initialized by a call to elf_symfile_init, which
1204 currently does nothing.
1206 SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
1207 in each section. We simplify it down to a single offset for all
1210 This function only does the minimum work necessary for letting the
1211 user "name" things symbolically; it does not read the entire symtab.
1212 Instead, it reads the external and static symbols and puts them in partial
1213 symbol tables. When more extensive information is requested of a
1214 file, the corresponding partial symbol table is mutated into a full
1215 fledged symbol table by going back and reading the symbols
1218 We look for sections with specific names, to tell us what debug
1219 format to look for: FIXME!!!
1221 elfstab_build_psymtabs() handles STABS symbols;
1222 mdebug_build_psymtabs() handles ECOFF debugging information.
1224 Note that ELF files have a "minimal" symbol table, which looks a lot
1225 like a COFF symbol table, but has only the minimal information necessary
1226 for linking. We process this also, and use the information to
1227 build gdb's minimal symbol table. This gives us some minimal debugging
1228 capability even for files compiled without -g. */
1231 elf_symfile_read (struct objfile *objfile, int symfile_flags)
1233 bfd *synth_abfd, *abfd = objfile->obfd;
1235 struct cleanup *back_to;
1236 long symcount = 0, dynsymcount = 0, synthcount, storage_needed;
1237 asymbol **symbol_table = NULL, **dyn_symbol_table = NULL;
1239 struct dbx_symfile_info *dbx;
1241 if (symtab_create_debug)
1243 fprintf_unfiltered (gdb_stdlog,
1244 "Reading minimal symbols of objfile %s ...\n",
1248 init_minimal_symbol_collection ();
1249 back_to = make_cleanup_discard_minimal_symbols ();
1251 memset ((char *) &ei, 0, sizeof (ei));
1253 /* Allocate struct to keep track of the symfile. */
1254 dbx = XCNEW (struct dbx_symfile_info);
1255 set_objfile_data (objfile, dbx_objfile_data_key, dbx);
1256 make_cleanup (free_elfinfo, (void *) objfile);
1258 /* Process the normal ELF symbol table first. This may write some
1259 chain of info into the dbx_symfile_info of the objfile, which can
1260 later be used by elfstab_offset_sections. */
1262 storage_needed = bfd_get_symtab_upper_bound (objfile->obfd);
1263 if (storage_needed < 0)
1264 error (_("Can't read symbols from %s: %s"),
1265 bfd_get_filename (objfile->obfd),
1266 bfd_errmsg (bfd_get_error ()));
1268 if (storage_needed > 0)
1270 symbol_table = (asymbol **) xmalloc (storage_needed);
1271 make_cleanup (xfree, symbol_table);
1272 symcount = bfd_canonicalize_symtab (objfile->obfd, symbol_table);
1275 error (_("Can't read symbols from %s: %s"),
1276 bfd_get_filename (objfile->obfd),
1277 bfd_errmsg (bfd_get_error ()));
1279 elf_symtab_read (objfile, ST_REGULAR, symcount, symbol_table, 0);
1282 /* Add the dynamic symbols. */
1284 storage_needed = bfd_get_dynamic_symtab_upper_bound (objfile->obfd);
1286 if (storage_needed > 0)
1288 /* Memory gets permanently referenced from ABFD after
1289 bfd_get_synthetic_symtab so it must not get freed before ABFD gets.
1290 It happens only in the case when elf_slurp_reloc_table sees
1291 asection->relocation NULL. Determining which section is asection is
1292 done by _bfd_elf_get_synthetic_symtab which is all a bfd
1293 implementation detail, though. */
1295 dyn_symbol_table = bfd_alloc (abfd, storage_needed);
1296 dynsymcount = bfd_canonicalize_dynamic_symtab (objfile->obfd,
1299 if (dynsymcount < 0)
1300 error (_("Can't read symbols from %s: %s"),
1301 bfd_get_filename (objfile->obfd),
1302 bfd_errmsg (bfd_get_error ()));
1304 elf_symtab_read (objfile, ST_DYNAMIC, dynsymcount, dyn_symbol_table, 0);
1306 elf_rel_plt_read (objfile, dyn_symbol_table);
1309 /* Contrary to binutils --strip-debug/--only-keep-debug the strip command from
1310 elfutils (eu-strip) moves even the .symtab section into the .debug file.
1312 bfd_get_synthetic_symtab on ppc64 for each function descriptor ELF symbol
1313 'name' creates a new BSF_SYNTHETIC ELF symbol '.name' with its code
1314 address. But with eu-strip files bfd_get_synthetic_symtab would fail to
1315 read the code address from .opd while it reads the .symtab section from
1316 a separate debug info file as the .opd section is SHT_NOBITS there.
1318 With SYNTH_ABFD the .opd section will be read from the original
1319 backlinked binary where it is valid. */
1321 if (objfile->separate_debug_objfile_backlink)
1322 synth_abfd = objfile->separate_debug_objfile_backlink->obfd;
1326 /* Add synthetic symbols - for instance, names for any PLT entries. */
1328 synthcount = bfd_get_synthetic_symtab (synth_abfd, symcount, symbol_table,
1329 dynsymcount, dyn_symbol_table,
1333 asymbol **synth_symbol_table;
1336 make_cleanup (xfree, synthsyms);
1337 synth_symbol_table = xmalloc (sizeof (asymbol *) * synthcount);
1338 for (i = 0; i < synthcount; i++)
1339 synth_symbol_table[i] = synthsyms + i;
1340 make_cleanup (xfree, synth_symbol_table);
1341 elf_symtab_read (objfile, ST_SYNTHETIC, synthcount,
1342 synth_symbol_table, 1);
1345 /* Install any minimal symbols that have been collected as the current
1346 minimal symbols for this objfile. The debug readers below this point
1347 should not generate new minimal symbols; if they do it's their
1348 responsibility to install them. "mdebug" appears to be the only one
1349 which will do this. */
1351 install_minimal_symbols (objfile);
1352 do_cleanups (back_to);
1354 /* Now process debugging information, which is contained in
1355 special ELF sections. */
1357 /* We first have to find them... */
1358 bfd_map_over_sections (abfd, elf_locate_sections, (void *) & ei);
1360 /* ELF debugging information is inserted into the psymtab in the
1361 order of least informative first - most informative last. Since
1362 the psymtab table is searched `most recent insertion first' this
1363 increases the probability that more detailed debug information
1364 for a section is found.
1366 For instance, an object file might contain both .mdebug (XCOFF)
1367 and .debug_info (DWARF2) sections then .mdebug is inserted first
1368 (searched last) and DWARF2 is inserted last (searched first). If
1369 we don't do this then the XCOFF info is found first - for code in
1370 an included file XCOFF info is useless. */
1374 const struct ecoff_debug_swap *swap;
1376 /* .mdebug section, presumably holding ECOFF debugging
1378 swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap;
1380 elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect);
1386 /* Stab sections have an associated string table that looks like
1387 a separate section. */
1388 str_sect = bfd_get_section_by_name (abfd, ".stabstr");
1390 /* FIXME should probably warn about a stab section without a stabstr. */
1392 elfstab_build_psymtabs (objfile,
1395 bfd_section_size (abfd, str_sect));
1398 if (dwarf2_has_info (objfile, NULL))
1400 /* elf_sym_fns_gdb_index cannot handle simultaneous non-DWARF debug
1401 information present in OBJFILE. If there is such debug info present
1402 never use .gdb_index. */
1404 if (!objfile_has_partial_symbols (objfile)
1405 && dwarf2_initialize_objfile (objfile))
1406 objfile->sf = &elf_sym_fns_gdb_index;
1409 /* It is ok to do this even if the stabs reader made some
1410 partial symbols, because OBJF_PSYMTABS_READ has not been
1411 set, and so our lazy reader function will still be called
1413 objfile->sf = &elf_sym_fns_lazy_psyms;
1416 /* If the file has its own symbol tables it has no separate debug
1417 info. `.dynsym'/`.symtab' go to MSYMBOLS, `.debug_info' goes to
1418 SYMTABS/PSYMTABS. `.gnu_debuglink' may no longer be present with
1419 `.note.gnu.build-id'.
1421 .gnu_debugdata is !objfile_has_partial_symbols because it contains only
1422 .symtab, not .debug_* section. But if we already added .gnu_debugdata as
1423 an objfile via find_separate_debug_file_in_section there was no separate
1424 debug info available. Therefore do not attempt to search for another one,
1425 objfile->separate_debug_objfile->separate_debug_objfile GDB guarantees to
1426 be NULL and we would possibly violate it. */
1428 else if (!objfile_has_partial_symbols (objfile)
1429 && objfile->separate_debug_objfile == NULL
1430 && objfile->separate_debug_objfile_backlink == NULL)
1434 debugfile = find_separate_debug_file_by_buildid (objfile);
1436 if (debugfile == NULL)
1437 debugfile = find_separate_debug_file_by_debuglink (objfile);
1441 struct cleanup *cleanup = make_cleanup (xfree, debugfile);
1442 bfd *abfd = symfile_bfd_open (debugfile);
1444 make_cleanup_bfd_unref (abfd);
1445 symbol_file_add_separate (abfd, symfile_flags, objfile);
1446 do_cleanups (cleanup);
1450 if (symtab_create_debug)
1451 fprintf_unfiltered (gdb_stdlog, "Done reading minimal symbols.\n");
1454 /* Callback to lazily read psymtabs. */
1457 read_psyms (struct objfile *objfile)
1459 if (dwarf2_has_info (objfile, NULL))
1460 dwarf2_build_psymtabs (objfile);
1463 /* This cleans up the objfile's dbx symfile info, and the chain of
1464 stab_section_info's, that might be dangling from it. */
1467 free_elfinfo (void *objp)
1469 struct objfile *objfile = (struct objfile *) objp;
1470 struct dbx_symfile_info *dbxinfo = DBX_SYMFILE_INFO (objfile);
1471 struct stab_section_info *ssi, *nssi;
1473 ssi = dbxinfo->stab_section_info;
1481 dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */
1485 /* Initialize anything that needs initializing when a completely new symbol
1486 file is specified (not just adding some symbols from another file, e.g. a
1489 We reinitialize buildsym, since we may be reading stabs from an ELF
1493 elf_new_init (struct objfile *ignore)
1495 stabsread_new_init ();
1496 buildsym_new_init ();
1499 /* Perform any local cleanups required when we are done with a particular
1500 objfile. I.E, we are in the process of discarding all symbol information
1501 for an objfile, freeing up all memory held for it, and unlinking the
1502 objfile struct from the global list of known objfiles. */
1505 elf_symfile_finish (struct objfile *objfile)
1507 dwarf2_free_objfile (objfile);
1510 /* ELF specific initialization routine for reading symbols.
1512 It is passed a pointer to a struct sym_fns which contains, among other
1513 things, the BFD for the file whose symbols are being read, and a slot for
1514 a pointer to "private data" which we can fill with goodies.
1516 For now at least, we have nothing in particular to do, so this function is
1520 elf_symfile_init (struct objfile *objfile)
1522 /* ELF objects may be reordered, so set OBJF_REORDERED. If we
1523 find this causes a significant slowdown in gdb then we could
1524 set it in the debug symbol readers only when necessary. */
1525 objfile->flags |= OBJF_REORDERED;
1528 /* When handling an ELF file that contains Sun STABS debug info,
1529 some of the debug info is relative to the particular chunk of the
1530 section that was generated in its individual .o file. E.g.
1531 offsets to static variables are relative to the start of the data
1532 segment *for that module before linking*. This information is
1533 painfully squirreled away in the ELF symbol table as local symbols
1534 with wierd names. Go get 'em when needed. */
1537 elfstab_offset_sections (struct objfile *objfile, struct partial_symtab *pst)
1539 const char *filename = pst->filename;
1540 struct dbx_symfile_info *dbx = DBX_SYMFILE_INFO (objfile);
1541 struct stab_section_info *maybe = dbx->stab_section_info;
1542 struct stab_section_info *questionable = 0;
1545 /* The ELF symbol info doesn't include path names, so strip the path
1546 (if any) from the psymtab filename. */
1547 filename = lbasename (filename);
1549 /* FIXME: This linear search could speed up significantly
1550 if it was chained in the right order to match how we search it,
1551 and if we unchained when we found a match. */
1552 for (; maybe; maybe = maybe->next)
1554 if (filename[0] == maybe->filename[0]
1555 && filename_cmp (filename, maybe->filename) == 0)
1557 /* We found a match. But there might be several source files
1558 (from different directories) with the same name. */
1559 if (0 == maybe->found)
1561 questionable = maybe; /* Might use it later. */
1565 if (maybe == 0 && questionable != 0)
1567 complaint (&symfile_complaints,
1568 _("elf/stab section information questionable for %s"),
1570 maybe = questionable;
1575 /* Found it! Allocate a new psymtab struct, and fill it in. */
1577 pst->section_offsets = (struct section_offsets *)
1578 obstack_alloc (&objfile->objfile_obstack,
1579 SIZEOF_N_SECTION_OFFSETS (objfile->num_sections));
1580 for (i = 0; i < maybe->num_sections; i++)
1581 (pst->section_offsets)->offsets[i] = maybe->sections[i];
1585 /* We were unable to find any offsets for this file. Complain. */
1586 if (dbx->stab_section_info) /* If there *is* any info, */
1587 complaint (&symfile_complaints,
1588 _("elf/stab section information missing for %s"), filename);
1591 /* Implementation of `sym_get_probes', as documented in symfile.h. */
1593 static VEC (probe_p) *
1594 elf_get_probes (struct objfile *objfile)
1596 VEC (probe_p) *probes_per_objfile;
1598 /* Have we parsed this objfile's probes already? */
1599 probes_per_objfile = objfile_data (objfile, probe_key);
1601 if (!probes_per_objfile)
1604 const struct probe_ops *probe_ops;
1606 /* Here we try to gather information about all types of probes from the
1608 for (ix = 0; VEC_iterate (probe_ops_cp, all_probe_ops, ix, probe_ops);
1610 probe_ops->get_probes (&probes_per_objfile, objfile);
1612 if (probes_per_objfile == NULL)
1614 VEC_reserve (probe_p, probes_per_objfile, 1);
1615 gdb_assert (probes_per_objfile != NULL);
1618 set_objfile_data (objfile, probe_key, probes_per_objfile);
1621 return probes_per_objfile;
1624 /* Implementation of `sym_get_probe_argument_count', as documented in
1628 elf_get_probe_argument_count (struct probe *probe)
1630 return probe->pops->get_probe_argument_count (probe);
1633 /* Implementation of `sym_evaluate_probe_argument', as documented in
1636 static struct value *
1637 elf_evaluate_probe_argument (struct probe *probe, unsigned n)
1639 return probe->pops->evaluate_probe_argument (probe, n);
1642 /* Implementation of `sym_compile_to_ax', as documented in symfile.h. */
1645 elf_compile_to_ax (struct probe *probe,
1646 struct agent_expr *expr,
1647 struct axs_value *value,
1650 probe->pops->compile_to_ax (probe, expr, value, n);
1653 /* Implementation of `sym_relocate_probe', as documented in symfile.h. */
1656 elf_symfile_relocate_probe (struct objfile *objfile,
1657 struct section_offsets *new_offsets,
1658 struct section_offsets *delta)
1661 VEC (probe_p) *probes = objfile_data (objfile, probe_key);
1662 struct probe *probe;
1664 for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++)
1665 probe->pops->relocate (probe, ANOFFSET (delta, SECT_OFF_TEXT (objfile)));
1668 /* Helper function used to free the space allocated for storing SystemTap
1669 probe information. */
1672 probe_key_free (struct objfile *objfile, void *d)
1675 VEC (probe_p) *probes = d;
1676 struct probe *probe;
1678 for (ix = 0; VEC_iterate (probe_p, probes, ix, probe); ix++)
1679 probe->pops->destroy (probe);
1681 VEC_free (probe_p, probes);
1686 /* Implementation `sym_probe_fns', as documented in symfile.h. */
1688 static const struct sym_probe_fns elf_probe_fns =
1690 elf_get_probes, /* sym_get_probes */
1691 elf_get_probe_argument_count, /* sym_get_probe_argument_count */
1692 elf_evaluate_probe_argument, /* sym_evaluate_probe_argument */
1693 elf_compile_to_ax, /* sym_compile_to_ax */
1694 elf_symfile_relocate_probe, /* sym_relocate_probe */
1697 /* Register that we are able to handle ELF object file formats. */
1699 static const struct sym_fns elf_sym_fns =
1701 bfd_target_elf_flavour,
1702 elf_new_init, /* init anything gbl to entire symtab */
1703 elf_symfile_init, /* read initial info, setup for sym_read() */
1704 elf_symfile_read, /* read a symbol file into symtab */
1705 NULL, /* sym_read_psymbols */
1706 elf_symfile_finish, /* finished with file, cleanup */
1707 default_symfile_offsets, /* Translate ext. to int. relocation */
1708 elf_symfile_segments, /* Get segment information from a file. */
1710 default_symfile_relocate, /* Relocate a debug section. */
1711 &elf_probe_fns, /* sym_probe_fns */
1715 /* The same as elf_sym_fns, but not registered and lazily reads
1718 static const struct sym_fns elf_sym_fns_lazy_psyms =
1720 bfd_target_elf_flavour,
1721 elf_new_init, /* init anything gbl to entire symtab */
1722 elf_symfile_init, /* read initial info, setup for sym_read() */
1723 elf_symfile_read, /* read a symbol file into symtab */
1724 read_psyms, /* sym_read_psymbols */
1725 elf_symfile_finish, /* finished with file, cleanup */
1726 default_symfile_offsets, /* Translate ext. to int. relocation */
1727 elf_symfile_segments, /* Get segment information from a file. */
1729 default_symfile_relocate, /* Relocate a debug section. */
1730 &elf_probe_fns, /* sym_probe_fns */
1734 /* The same as elf_sym_fns, but not registered and uses the
1735 DWARF-specific GNU index rather than psymtab. */
1736 static const struct sym_fns elf_sym_fns_gdb_index =
1738 bfd_target_elf_flavour,
1739 elf_new_init, /* init anything gbl to entire symab */
1740 elf_symfile_init, /* read initial info, setup for sym_red() */
1741 elf_symfile_read, /* read a symbol file into symtab */
1742 NULL, /* sym_read_psymbols */
1743 elf_symfile_finish, /* finished with file, cleanup */
1744 default_symfile_offsets, /* Translate ext. to int. relocatin */
1745 elf_symfile_segments, /* Get segment information from a file. */
1747 default_symfile_relocate, /* Relocate a debug section. */
1748 &elf_probe_fns, /* sym_probe_fns */
1749 &dwarf2_gdb_index_functions
1752 /* STT_GNU_IFUNC resolver vector to be installed to gnu_ifunc_fns_p. */
1754 static const struct gnu_ifunc_fns elf_gnu_ifunc_fns =
1756 elf_gnu_ifunc_resolve_addr,
1757 elf_gnu_ifunc_resolve_name,
1758 elf_gnu_ifunc_resolver_stop,
1759 elf_gnu_ifunc_resolver_return_stop
1763 _initialize_elfread (void)
1765 probe_key = register_objfile_data_with_cleanup (NULL, probe_key_free);
1766 add_symtab_fns (&elf_sym_fns);
1768 elf_objfile_gnu_ifunc_cache_data = register_objfile_data ();
1769 gnu_ifunc_fns_p = &elf_gnu_ifunc_fns;