1 /* Read ELF (Executable and Linking Format) object files for GDB.
3 Copyright (C) 1991-2023 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/>. */
25 #include "elf/common.h"
26 #include "elf/internal.h"
31 #include "stabsread.h"
33 #include "filenames.h"
35 #include "arch-utils.h"
39 #include "gdbthread.h"
47 #include "mdebugread.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"
55 /* Whether ctf should always be read, or only if no dwarf is present. */
56 static bool always_read_ctf
;
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. */
64 asection
*stabsect
; /* Section pointer for .stab section */
65 asection
*mdebugsect
; /* Section pointer for .mdebug section */
66 asection
*ctfsect
; /* Section pointer for .ctf section */
69 /* Type for per-BFD data. */
71 typedef std::vector
<std::unique_ptr
<probe
>> elfread_data
;
73 /* Per-BFD data for probe info. */
75 static const registry
<bfd
>::key
<elfread_data
> probe_key
;
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. */
82 #define SYMBOL_GOT_PLT_SUFFIX "@got.plt"
84 /* Locate the segments in ABFD. */
86 static symfile_segment_data_up
87 elf_symfile_segments (bfd
*abfd
)
89 Elf_Internal_Phdr
*phdrs
, **segments
;
91 int num_phdrs
, num_segments
, num_sections
, i
;
94 phdrs_size
= bfd_get_elf_phdr_upper_bound (abfd
);
98 phdrs
= (Elf_Internal_Phdr
*) alloca (phdrs_size
);
99 num_phdrs
= bfd_get_elf_phdrs (abfd
, phdrs
);
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
];
109 if (num_segments
== 0)
112 symfile_segment_data_up
data (new symfile_segment_data
);
113 data
->segments
.reserve (num_segments
);
115 for (i
= 0; i
< num_segments
; i
++)
116 data
->segments
.emplace_back (segments
[i
]->p_vaddr
, segments
[i
]->p_memsz
);
118 num_sections
= bfd_count_sections (abfd
);
120 /* All elements are initialized to 0 (map to no segment). */
121 data
->segment_info
.resize (num_sections
);
123 for (i
= 0, sect
= abfd
->sections
; sect
!= NULL
; i
++, sect
= sect
->next
)
127 if ((bfd_section_flags (sect
) & SEC_ALLOC
) == 0)
130 Elf_Internal_Shdr
*this_hdr
= &elf_section_data (sect
)->this_hdr
;
132 for (j
= 0; j
< num_segments
; j
++)
133 if (ELF_SECTION_IN_SEGMENT (this_hdr
, segments
[j
]))
135 data
->segment_info
[i
] = j
+ 1;
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. */
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
));
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.
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
173 We also recognize the ".stab" sections used by the Sun compilers
174 released with Solaris 2.
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.
182 elf_locate_sections (asection
*sectp
, struct elfinfo
*ei
)
184 if (strcmp (sectp
->name
, ".stab") == 0)
186 ei
->stabsect
= sectp
;
188 else if (strcmp (sectp
->name
, ".mdebug") == 0)
190 ei
->mdebugsect
= sectp
;
192 else if (strcmp (sectp
->name
, ".ctf") == 0)
198 static struct minimal_symbol
*
199 record_minimal_symbol (minimal_symbol_reader
&reader
,
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
)
205 struct gdbarch
*gdbarch
= objfile
->arch ();
207 if (ms_type
== mst_text
|| ms_type
== mst_file_text
208 || ms_type
== mst_text_gnu_ifunc
)
210 = unrelocated_addr (gdbarch_addr_bits_remove (gdbarch
,
211 CORE_ADDR (address
)));
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
);
222 return reader
.record_full (name
, copy_name
, address
, ms_type
, section_index
);
225 /* Read the symbol table of an ELF file.
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.
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. */
239 #define ST_SYNTHETIC 2
242 elf_symtab_read (minimal_symbol_reader
&reader
,
243 struct objfile
*objfile
, int type
,
244 long number_of_symbols
, asymbol
**symbol_table
,
247 struct gdbarch
*gdbarch
= objfile
->arch ();
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
257 = gdbarch_elf_make_msymbol_special_p (gdbarch
);
259 for (i
= 0; i
< number_of_symbols
; i
++)
261 sym
= symbol_table
[i
];
262 if (sym
->name
== NULL
|| *sym
->name
== '\0')
264 /* Skip names that don't exist (shouldn't happen), or names
265 that are null strings (may happen). */
269 elf_symbol_type
*elf_sym
= (elf_symbol_type
*) sym
;
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
))
276 if (gdbarch_record_special_symbol_p (gdbarch
))
277 gdbarch_record_special_symbol (gdbarch
, objfile
, sym
);
281 if (type
== ST_DYNAMIC
282 && sym
->section
== bfd_und_section_ptr
283 && (sym
->flags
& BSF_FUNCTION
))
285 struct minimal_symbol
*msym
;
286 bfd
*abfd
= objfile
->obfd
.get ();
289 /* Symbol is a reference to a function defined in
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
;
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
)
307 if ((bfd_section_flags (sect
) & SEC_ALLOC
) == 0)
310 if (symaddr
>= bfd_section_vma (sect
)
311 && symaddr
< bfd_section_vma (sect
)
312 + bfd_section_size (sect
))
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
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
)
335 msym
= record_minimal_symbol
336 (reader
, sym
->name
, copy_names
,
337 unrelocated_addr (symaddr
),
338 mst_solib_trampoline
, sect
, objfile
);
341 msym
->filename
= filesymname
;
342 if (elf_make_msymbol_special_p
)
343 gdbarch_elf_make_msymbol_special (gdbarch
, sym
, msym
);
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
)
353 if (sym
->flags
& BSF_FILE
)
354 filesymname
= objfile
->intern (sym
->name
);
355 else if (sym
->flags
& BSF_SECTION_SYM
)
357 else if (sym
->flags
& (BSF_GLOBAL
| BSF_LOCAL
| BSF_WEAK
360 struct minimal_symbol
*msym
;
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
)
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.
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
;
389 case SHN_MIPS_ACOMMON
:
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
)
400 if (sym
->name
[0] == '.')
404 else if (sym
->section
->flags
& SEC_CODE
)
406 if (sym
->flags
& (BSF_GLOBAL
| BSF_WEAK
| BSF_GNU_UNIQUE
))
408 if (sym
->flags
& BSF_GNU_INDIRECT_FUNCTION
)
409 ms_type
= mst_text_gnu_ifunc
;
413 /* The BSF_SYNTHETIC check is there to omit ppc64 function
414 descriptors mistaken for static functions starting with 'L'.
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). */
431 ms_type
= mst_file_text
;
434 else if (sym
->section
->flags
& SEC_ALLOC
)
436 if (sym
->flags
& (BSF_GLOBAL
| BSF_WEAK
| BSF_GNU_UNIQUE
))
438 if (sym
->flags
& BSF_GNU_INDIRECT_FUNCTION
)
440 ms_type
= mst_data_gnu_ifunc
;
442 else if (sym
->section
->flags
& SEC_LOAD
)
451 else if (sym
->flags
& BSF_LOCAL
)
453 if (sym
->section
->flags
& SEC_LOAD
)
455 ms_type
= mst_file_data
;
459 ms_type
= mst_file_bss
;
464 ms_type
= mst_unknown
;
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. */
476 msym
= record_minimal_symbol
477 (reader
, sym
->name
, copy_names
, unrelocated_addr (symaddr
),
478 ms_type
, sym
->section
, objfile
);
482 /* NOTE: uweigand-20071112: A synthetic symbol does not have an
484 if (type
!= ST_SYNTHETIC
)
486 /* Pass symbol size field in via BFD. FIXME!!! */
487 msym
->set_size (elf_sym
->internal_elf_sym
.st_size
);
490 msym
->filename
= filesymname
;
491 if (elf_make_msymbol_special_p
)
492 gdbarch_elf_make_msymbol_special (gdbarch
, sym
, msym
);
495 /* If we see a default versioned symbol, install it under
496 its version-less name. */
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;
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
);
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
)
519 struct minimal_symbol
*mtramp
;
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
);
527 mtramp
->set_size (msym
->size());
528 mtramp
->created_by_gdb
= 1;
529 mtramp
->filename
= filesymname
;
530 if (elf_make_msymbol_special_p
)
531 gdbarch_elf_make_msymbol_special (gdbarch
,
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. */
549 elf_rel_plt_read (minimal_symbol_reader
&reader
,
550 struct objfile
*objfile
, asymbol
**dyn_symbol_table
)
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 ();
560 if (objfile
->separate_debug_objfile_backlink
)
563 got_plt
= bfd_get_section_by_name (obfd
, ".got.plt");
566 /* For platforms where there is no separate .got.plt. */
567 got_plt
= bfd_get_section_by_name (obfd
, ".got");
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;
577 int got_plt_elf_idx
= elf_section_data (got_plt
)->this_idx
;
579 /* This search algorithm is from _bfd_elf_canonicalize_dynamic_reloc. */
580 for (relplt
= obfd
->sections
; relplt
!= NULL
; relplt
= relplt
->next
)
582 const auto &this_hdr
= elf_section_data (relplt
)->this_hdr
;
584 if (this_hdr
.sh_type
== SHT_REL
|| this_hdr
.sh_type
== SHT_RELA
)
586 if (this_hdr
.sh_info
== plt_elf_idx
587 || this_hdr
.sh_info
== got_plt_elf_idx
)
594 if (! bed
->s
->slurp_reloc_table (obfd
, relplt
, dyn_symbol_table
, TRUE
))
597 std::string string_buffer
;
599 /* Does ADDRESS reside in SECTION of OBFD? */
600 auto within_section
= [obfd
] (asection
*section
, CORE_ADDR address
)
605 return (bfd_section_vma (section
) <= address
606 && (address
< bfd_section_vma (section
)
607 + bfd_section_size (section
)));
610 reloc_count
= relplt
->size
/ elf_section_data (relplt
)->this_hdr
.sh_entsize
;
611 for (reloc
= 0; reloc
< reloc_count
; reloc
++)
614 struct minimal_symbol
*msym
;
616 const char *got_suffix
= SYMBOL_GOT_PLT_SUFFIX
;
617 const size_t got_suffix_len
= strlen (SYMBOL_GOT_PLT_SUFFIX
);
619 name
= bfd_asymbol_name (*relplt
->relocation
[reloc
].sym_ptr_ptr
);
620 address
= relplt
->relocation
[reloc
].address
;
622 asection
*msym_section
;
624 /* Does the pointer reside in either the .got.plt or .plt
626 if (within_section (got_plt
, address
))
627 msym_section
= got_plt
;
628 else if (within_section (plt
, address
))
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. */
638 string_buffer
.assign (name
);
639 string_buffer
.append (got_suffix
, got_suffix
+ got_suffix_len
);
641 msym
= record_minimal_symbol (reader
, string_buffer
,
642 true, unrelocated_addr (address
),
643 mst_slot_got_plt
, msym_section
, objfile
);
645 msym
->set_size (ptr_size
);
649 /* The data pointer is htab_t for gnu_ifunc_record_cache_unchecked. */
651 static const registry
<objfile
>::key
<htab
, htab_deleter
>
652 elf_objfile_gnu_ifunc_cache_data
;
654 /* Map function names to CORE_ADDR in elf_objfile_gnu_ifunc_cache_data. */
656 struct elf_gnu_ifunc_cache
658 /* This is always a function entry address, not a function descriptor. */
664 /* htab_hash for elf_objfile_gnu_ifunc_cache_data. */
667 elf_gnu_ifunc_cache_hash (const void *a_voidp
)
669 const struct elf_gnu_ifunc_cache
*a
670 = (const struct elf_gnu_ifunc_cache
*) a_voidp
;
672 return htab_hash_string (a
->name
);
675 /* htab_eq for elf_objfile_gnu_ifunc_cache_data. */
678 elf_gnu_ifunc_cache_eq (const void *a_voidp
, const void *b_voidp
)
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
;
685 return strcmp (a
->name
, b
->name
) == 0;
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.
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
697 elf_gnu_ifunc_record_cache (const char *name
, CORE_ADDR addr
)
699 struct bound_minimal_symbol msym
;
700 struct objfile
*objfile
;
702 struct elf_gnu_ifunc_cache entry_local
, *entry_p
;
705 msym
= lookup_minimal_symbol_by_pc (addr
);
706 if (msym
.minsym
== NULL
)
708 if (msym
.value_address () != addr
)
710 objfile
= msym
.objfile
;
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
);
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)
723 if (strcmp (target_name
, "_PROCEDURE_LINKAGE_TABLE_") == 0)
726 htab
= elf_objfile_gnu_ifunc_cache_data
.get (objfile
);
729 htab
= htab_create_alloc (1, elf_gnu_ifunc_cache_hash
,
730 elf_gnu_ifunc_cache_eq
,
731 NULL
, xcalloc
, xfree
);
732 elf_objfile_gnu_ifunc_cache_data
.set (objfile
, htab
);
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
);
740 = (struct elf_gnu_ifunc_cache
*) obstack_finish (&objfile
->objfile_obstack
);
742 slot
= htab_find_slot (htab
, entry_p
, INSERT
);
745 struct elf_gnu_ifunc_cache
*entry_found_p
746 = (struct elf_gnu_ifunc_cache
*) *slot
;
747 struct gdbarch
*gdbarch
= objfile
->arch ();
749 if (entry_found_p
->addr
!= addr
)
751 /* This case indicates buggy inferior program, the resolved address
752 should never change. */
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
));
760 /* New ENTRY_P is here leaked/duplicate in the OBJFILE obstack. */
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.
771 Only the elf_objfile_gnu_ifunc_cache_data hash table is searched by this
775 elf_gnu_ifunc_resolve_by_cache (const char *name
, CORE_ADDR
*addr_p
)
779 /* FIXME: we only search the initial namespace.
781 To search other namespaces, we would need to provide context, e.g. in
782 form of an objfile in that namespace. */
783 gdbarch_iterate_over_objfiles_in_search_order
784 (current_inferior ()->arch (),
785 [name
, &addr_p
, &found
] (struct objfile
*objfile
)
788 elf_gnu_ifunc_cache
*entry_p
;
791 htab
= elf_objfile_gnu_ifunc_cache_data
.get (objfile
);
795 entry_p
= ((elf_gnu_ifunc_cache
*)
796 alloca (sizeof (*entry_p
) + strlen (name
)));
797 strcpy (entry_p
->name
, name
);
799 slot
= htab_find_slot (htab
, entry_p
, NO_INSERT
);
802 entry_p
= (elf_gnu_ifunc_cache
*) *slot
;
803 gdb_assert (entry_p
!= NULL
);
806 *addr_p
= entry_p
->addr
;
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.
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. */
824 elf_gnu_ifunc_resolve_by_got (const char *name
, CORE_ADDR
*addr_p
)
827 const size_t got_suffix_len
= strlen (SYMBOL_GOT_PLT_SUFFIX
);
830 name_got_plt
= (char *) alloca (strlen (name
) + got_suffix_len
+ 1);
831 sprintf (name_got_plt
, "%s" SYMBOL_GOT_PLT_SUFFIX
, name
);
833 /* FIXME: we only search the initial namespace.
835 To search other namespaces, we would need to provide context, e.g. in
836 form of an objfile in that namespace. */
837 gdbarch_iterate_over_objfiles_in_search_order
838 (current_inferior ()->arch (),
839 [name
, name_got_plt
, &addr_p
, &found
] (struct objfile
*objfile
)
841 bfd
*obfd
= objfile
->obfd
.get ();
842 struct gdbarch
*gdbarch
= objfile
->arch ();
843 type
*ptr_type
= builtin_type (gdbarch
)->builtin_data_ptr
;
844 size_t ptr_size
= ptr_type
->length ();
845 CORE_ADDR pointer_address
, addr
;
847 gdb_byte
*buf
= (gdb_byte
*) alloca (ptr_size
);
848 bound_minimal_symbol msym
;
850 msym
= lookup_minimal_symbol (name_got_plt
, NULL
, objfile
);
851 if (msym
.minsym
== NULL
)
853 if (msym
.minsym
->type () != mst_slot_got_plt
)
855 pointer_address
= msym
.value_address ();
857 plt
= bfd_get_section_by_name (obfd
, ".plt");
861 if (msym
.minsym
->size () != ptr_size
)
863 if (target_read_memory (pointer_address
, buf
, ptr_size
) != 0)
865 addr
= extract_typed_address (buf
, ptr_type
);
866 addr
= gdbarch_convert_from_func_ptr_addr
867 (gdbarch
, addr
, current_inferior ()->top_target ());
868 addr
= gdbarch_addr_bits_remove (gdbarch
, addr
);
870 if (elf_gnu_ifunc_record_cache (name
, addr
))
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.
889 Both the elf_objfile_gnu_ifunc_cache_data hash table and
890 SYMBOL_GOT_PLT_SUFFIX locations are searched by this function. */
893 elf_gnu_ifunc_resolve_name (const char *name
, CORE_ADDR
*addr_p
)
895 if (elf_gnu_ifunc_resolve_by_cache (name
, addr_p
))
898 if (elf_gnu_ifunc_resolve_by_got (name
, addr_p
))
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.
910 elf_gnu_ifunc_resolve_addr (struct gdbarch
*gdbarch
, CORE_ADDR pc
)
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
;
917 struct value
*hwcap_val
;
919 /* Try first any non-intrusive methods without an inferior call. */
921 if (find_pc_partial_function (pc
, &name_at_pc
, &start_at_pc
, NULL
)
922 && start_at_pc
== pc
)
924 if (elf_gnu_ifunc_resolve_name (name_at_pc
, &address
))
930 function
= value::allocate (func_func_type
);
931 function
->set_lval (lval_memory
);
932 function
->set_address (pc
);
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. */
938 target_auxv_search (AT_HWCAP
, &hwcap
);
939 hwcap_val
= value_from_longest (builtin_type (gdbarch
)
940 ->builtin_unsigned_long
, hwcap
);
941 address_val
= call_function_by_hand (function
, NULL
, hwcap_val
);
942 address
= value_as_address (address_val
);
943 address
= gdbarch_convert_from_func_ptr_addr
944 (gdbarch
, address
, current_inferior ()->top_target ());
945 address
= gdbarch_addr_bits_remove (gdbarch
, address
);
948 elf_gnu_ifunc_record_cache (name_at_pc
, address
);
953 /* Handle inferior hit of bp_gnu_ifunc_resolver, see its definition. */
956 elf_gnu_ifunc_resolver_stop (code_breakpoint
*b
)
958 struct breakpoint
*b_return
;
959 frame_info_ptr prev_frame
= get_prev_frame (get_current_frame ());
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
;
964 gdb_assert (b
->type
== bp_gnu_ifunc_resolver
);
966 for (b_return
= b
->related_breakpoint
; b_return
!= b
;
967 b_return
= b_return
->related_breakpoint
)
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
));
973 if (b_return
->thread
== thread_id
974 && b_return
->first_loc ().requested_address
== prev_pc
975 && b_return
->frame_id
== prev_frame_id
)
981 /* No need to call find_pc_line for symbols resolving as this is only
982 a helper breakpointer never shown to the user. */
985 sal
.pspace
= current_inferior ()->pspace
;
987 sal
.section
= find_pc_overlay (sal
.pc
);
990 = set_momentary_breakpoint (get_frame_arch (prev_frame
), sal
,
992 bp_gnu_ifunc_resolver_return
).release ();
994 /* set_momentary_breakpoint invalidates PREV_FRAME. */
997 /* Add new b_return to the ring list b->related_breakpoint. */
998 gdb_assert (b_return
->related_breakpoint
== b_return
);
999 b_return
->related_breakpoint
= b
->related_breakpoint
;
1000 b
->related_breakpoint
= b_return
;
1004 /* Handle inferior hit of bp_gnu_ifunc_resolver_return, see its definition. */
1007 elf_gnu_ifunc_resolver_return_stop (code_breakpoint
*b
)
1009 thread_info
*thread
= inferior_thread ();
1010 struct gdbarch
*gdbarch
= get_frame_arch (get_current_frame ());
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
;
1018 gdb_assert (b
->type
== bp_gnu_ifunc_resolver_return
);
1020 while (b
->related_breakpoint
!= b
)
1022 struct breakpoint
*b_next
= b
->related_breakpoint
;
1026 case bp_gnu_ifunc_resolver
:
1028 case bp_gnu_ifunc_resolver_return
:
1029 delete_breakpoint (b
);
1032 internal_error (_("handle_inferior_event: Invalid "
1033 "gnu-indirect-function breakpoint type %d"),
1036 b
= gdb::checked_static_cast
<code_breakpoint
*> (b_next
);
1038 gdb_assert (b
->type
== bp_gnu_ifunc_resolver
);
1039 gdb_assert (b
->has_single_location ());
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
);
1045 value
= value::allocate (value_type
);
1046 gdbarch_return_value_as_value (gdbarch
, func_func
, value_type
, regcache
,
1048 resolved_address
= value_as_address (value
);
1049 resolved_pc
= gdbarch_convert_from_func_ptr_addr
1050 (gdbarch
, resolved_address
, current_inferior ()->top_target ());
1051 resolved_pc
= gdbarch_addr_bits_remove (gdbarch
, resolved_pc
);
1053 gdb_assert (current_program_space
== b
->pspace
|| b
->pspace
== NULL
);
1054 elf_gnu_ifunc_record_cache (b
->locspec
->to_string (), resolved_pc
);
1056 b
->type
= bp_breakpoint
;
1057 update_breakpoint_locations (b
, current_program_space
,
1058 find_function_start_sal (resolved_pc
, NULL
, true),
1062 /* A helper function for elf_symfile_read that reads the minimal
1066 elf_read_minimal_symbols (struct objfile
*objfile
, int symfile_flags
,
1067 const struct elfinfo
*ei
)
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
;
1074 symtab_create_debug_printf ("reading minimal symbols of objfile %s",
1075 objfile_name (objfile
));
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. */
1082 if (objfile
->per_bfd
->minsyms_read
1083 && ei
->stabsect
== NULL
1084 && ei
->mdebugsect
== NULL
1085 && ei
->ctfsect
== NULL
)
1087 symtab_create_debug_printf ("minimal symbols were previously read");
1091 minimal_symbol_reader
reader (objfile
);
1093 /* Process the normal ELF symbol table first. */
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 ()));
1101 if (storage_needed
> 0)
1103 /* Memory gets permanently referenced from ABFD after
1104 bfd_canonicalize_symtab so it must not get freed before ABFD gets. */
1106 symbol_table
= (asymbol
**) bfd_alloc (abfd
, storage_needed
);
1107 symcount
= bfd_canonicalize_symtab (objfile
->obfd
.get (), symbol_table
);
1110 error (_("Can't read symbols from %s: %s"),
1111 bfd_get_filename (objfile
->obfd
.get ()),
1112 bfd_errmsg (bfd_get_error ()));
1114 elf_symtab_read (reader
, objfile
, ST_REGULAR
, symcount
, symbol_table
,
1118 /* Add the dynamic symbols. */
1120 storage_needed
= bfd_get_dynamic_symtab_upper_bound (objfile
->obfd
.get ());
1122 if (storage_needed
> 0)
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. */
1131 dyn_symbol_table
= (asymbol
**) bfd_alloc (abfd
, storage_needed
);
1132 dynsymcount
= bfd_canonicalize_dynamic_symtab (objfile
->obfd
.get (),
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 ()));
1140 elf_symtab_read (reader
, objfile
, ST_DYNAMIC
, dynsymcount
,
1141 dyn_symbol_table
, false);
1143 elf_rel_plt_read (reader
, objfile
, dyn_symbol_table
);
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.
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.
1155 With SYNTH_ABFD the .opd section will be read from the original
1156 backlinked binary where it is valid. */
1158 if (objfile
->separate_debug_objfile_backlink
)
1159 synth_abfd
= objfile
->separate_debug_objfile_backlink
->obfd
.get ();
1163 /* Add synthetic symbols - for instance, names for any PLT entries. */
1165 synthcount
= bfd_get_synthetic_symtab (synth_abfd
, symcount
, symbol_table
,
1166 dynsymcount
, dyn_symbol_table
,
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);
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. */
1191 symtab_create_debug_printf ("done reading minimal symbols");
1194 /* Dwarf-specific helper for elf_symfile_read. Return true if we managed to
1195 load dwarf debug info. */
1198 elf_symfile_read_dwarf2 (struct objfile
*objfile
,
1199 symfile_add_flags symfile_flags
)
1201 bool has_dwarf2
= true;
1203 if (dwarf2_has_info (objfile
, NULL
, true))
1204 dwarf2_initialize_objfile (objfile
);
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'.
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. */
1217 else if (!objfile
->has_partial_symbols ()
1218 && objfile
->separate_debug_objfile
== NULL
1219 && objfile
->separate_debug_objfile_backlink
== NULL
)
1221 deferred_warnings warnings
;
1223 std::string debugfile
1224 = find_separate_debug_file_by_buildid (objfile
, &warnings
);
1226 if (debugfile
.empty ())
1227 debugfile
= find_separate_debug_file_by_debuglink (objfile
, &warnings
);
1229 if (!debugfile
.empty ())
1231 gdb_bfd_ref_ptr debug_bfd
1232 (symfile_bfd_open_no_error (debugfile
.c_str ()));
1234 if (debug_bfd
!= nullptr)
1235 symbol_file_add_separate (debug_bfd
, debugfile
.c_str (),
1236 symfile_flags
, objfile
);
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 ());
1245 if (build_id
!= nullptr)
1247 gdb::unique_xmalloc_ptr
<char> symfile_path
;
1248 scoped_fd
fd (debuginfod_debuginfo_query (build_id
->data
,
1255 /* File successfully retrieved from server. */
1256 gdb_bfd_ref_ptr debug_bfd
1257 (symfile_bfd_open_no_error (symfile_path
.get ()));
1259 if (debug_bfd
!= nullptr
1260 && build_id_verify (debug_bfd
.get (), build_id
->size
,
1263 symbol_file_add_separate (debug_bfd
, symfile_path
.get (),
1264 symfile_flags
, objfile
);
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
)
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.
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
1291 We look for sections with specific names, to tell us what debug
1292 format to look for: FIXME!!!
1294 elfstab_build_psymtabs() handles STABS symbols;
1295 mdebug_build_psymtabs() handles ECOFF debugging information.
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. */
1304 elf_symfile_read (struct objfile
*objfile
, symfile_add_flags symfile_flags
)
1306 bfd
*abfd
= objfile
->obfd
.get ();
1309 memset ((char *) &ei
, 0, sizeof (ei
));
1310 if (!(objfile
->flags
& OBJF_READNEVER
))
1312 for (asection
*sect
: gdb_bfd_sections (abfd
))
1313 elf_locate_sections (sect
, &ei
);
1316 elf_read_minimal_symbols (objfile
, symfile_flags
, &ei
);
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.
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. */
1332 const struct ecoff_debug_swap
*swap
;
1334 /* .mdebug section, presumably holding ECOFF debugging
1336 swap
= get_elf_backend_data (abfd
)->elf_backend_ecoff_debug_swap
;
1338 elfmdebug_build_psymtabs (objfile
, swap
, ei
.mdebugsect
);
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");
1348 /* FIXME should probably warn about a stab section without a stabstr. */
1350 elfstab_build_psymtabs (objfile
,
1353 bfd_section_size (str_sect
));
1356 /* Read the CTF section only if there is no DWARF info. */
1357 if (always_read_ctf
&& ei
.ctfsect
)
1359 elfctf_build_psymtabs (objfile
);
1362 bool has_dwarf2
= elf_symfile_read_dwarf2 (objfile
, symfile_flags
);
1364 /* Read the CTF section only if there is no DWARF info. */
1365 if (!always_read_ctf
&& !has_dwarf2
&& ei
.ctfsect
)
1367 elfctf_build_psymtabs (objfile
);
1370 /* Copy relocations are used by some ABIs using the ELF format, so
1371 set the objfile flag indicating this fact. */
1372 objfile
->object_format_has_copy_relocs
= true;
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
1380 elf_new_init (struct objfile
*ignore
)
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. */
1390 elf_symfile_finish (struct objfile
*objfile
)
1394 /* ELF specific initialization routine for reading symbols. */
1397 elf_symfile_init (struct objfile
*objfile
)
1401 /* Implementation of `sym_get_probes', as documented in symfile.h. */
1403 static const elfread_data
&
1404 elf_get_probes (struct objfile
*objfile
)
1406 elfread_data
*probes_per_bfd
= probe_key
.get (objfile
->obfd
.get ());
1408 if (probes_per_bfd
== NULL
)
1410 probes_per_bfd
= probe_key
.emplace (objfile
->obfd
.get ());
1412 /* Here we try to gather information about all types of probes from the
1414 for (const static_probe_ops
*ops
: all_static_probe_ops
)
1415 ops
->get_probes (probes_per_bfd
, objfile
);
1418 return *probes_per_bfd
;
1423 /* Implementation `sym_probe_fns', as documented in symfile.h. */
1425 static const struct sym_probe_fns elf_probe_fns
=
1427 elf_get_probes
, /* sym_get_probes */
1430 /* Register that we are able to handle ELF object file formats. */
1432 static const struct sym_fns elf_sym_fns
=
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. */
1441 default_symfile_relocate
, /* Relocate a debug section. */
1442 &elf_probe_fns
, /* sym_probe_fns */
1445 /* STT_GNU_IFUNC resolver vector to be installed to gnu_ifunc_fns_p. */
1447 static const struct gnu_ifunc_fns elf_gnu_ifunc_fns
=
1449 elf_gnu_ifunc_resolve_addr
,
1450 elf_gnu_ifunc_resolve_name
,
1451 elf_gnu_ifunc_resolver_stop
,
1452 elf_gnu_ifunc_resolver_return_stop
1455 void _initialize_elfread ();
1457 _initialize_elfread ()
1459 add_symtab_fns (bfd_target_elf_flavour
, &elf_sym_fns
);
1461 gnu_ifunc_fns_p
= &elf_gnu_ifunc_fns
;
1463 /* Add "set always-read-ctf on/off". */
1464 add_setshow_boolean_cmd ("always-read-ctf", class_support
, &always_read_ctf
,
1466 Set whether CTF is always read."),
1468 Show whether CTF is always read."),
1470 When 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
);