1 From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
2 From: Fedora GDB patches <invalid@email.com>
3 Date: Fri, 27 Oct 2017 21:07:50 +0200
4 Subject: gdb-6.6-buildid-locate.patch
6 ;; New locating of the matching binaries from the pure core file (build-id).
9 diff --git a/gdb/build-id.c b/gdb/build-id.c
14 #include "filenames.h"
19 +#include "observable.h"
20 +#include "elf/external.h"
21 +#include "elf/internal.h"
22 +#include "elf/common.h"
24 +#include <sys/stat.h>
26 +#define BUILD_ID_VERBOSE_NONE 0
27 +#define BUILD_ID_VERBOSE_FILENAMES 1
28 +#define BUILD_ID_VERBOSE_BINARY_PARSE 2
29 +static int build_id_verbose = BUILD_ID_VERBOSE_FILENAMES;
31 +show_build_id_verbose (struct ui_file *file, int from_tty,
32 + struct cmd_list_element *c, const char *value)
34 + fprintf_filtered (file, _("Verbosity level of the build-id locator is %s.\n"),
37 +/* Locate NT_GNU_BUILD_ID and return its matching debug filename.
38 + FIXME: NOTE decoding should be unified with the BFD core notes decoding. */
40 +static struct bfd_build_id *
41 +build_id_buf_get (bfd *templ, gdb_byte *buf, bfd_size_type size)
46 + while (p < buf + size)
48 + /* FIXME: bad alignment assumption. */
49 + Elf_External_Note *xnp = (Elf_External_Note *) p;
50 + size_t namesz = H_GET_32 (templ, xnp->namesz);
51 + size_t descsz = H_GET_32 (templ, xnp->descsz);
52 + bfd_byte *descdata = (gdb_byte *) xnp->name + BFD_ALIGN (namesz, 4);
54 + if (H_GET_32 (templ, xnp->type) == NT_GNU_BUILD_ID
55 + && namesz == sizeof "GNU"
56 + && memcmp (xnp->name, "GNU", sizeof "GNU") == 0)
58 + size_t size = descsz;
59 + gdb_byte *data = (gdb_byte *) descdata;
60 + struct bfd_build_id *retval;
62 + retval = (struct bfd_build_id *) xmalloc (sizeof *retval - 1 + size);
63 + retval->size = size;
64 + memcpy (retval->data, data, size);
68 + p = descdata + BFD_ALIGN (descsz, 4);
75 const struct bfd_build_id *
76 -build_id_bfd_get (bfd *abfd)
77 +build_id_bfd_shdr_get (bfd *abfd)
79 if (!bfd_check_format (abfd, bfd_object))
81 @@ -42,6 +98,348 @@ build_id_bfd_get (bfd *abfd)
85 +/* Core files may have missing (corrupt) SHDR but PDHR is correct there.
86 + bfd_elf_bfd_from_remote_memory () has too much overhead by
87 + allocating/reading all the available ELF PT_LOADs. */
89 +static struct bfd_build_id *
90 +build_id_phdr_get (bfd *templ, bfd_vma loadbase, unsigned e_phnum,
91 + Elf_Internal_Phdr *i_phdr)
94 + struct bfd_build_id *retval = NULL;
96 + for (i = 0; i < e_phnum; i++)
97 + if (i_phdr[i].p_type == PT_NOTE && i_phdr[i].p_filesz > 0)
99 + Elf_Internal_Phdr *hdr = &i_phdr[i];
103 + buf = (gdb_byte *) xmalloc (hdr->p_filesz);
104 + err = target_read_memory (loadbase + i_phdr[i].p_vaddr, buf,
107 + retval = build_id_buf_get (templ, buf, hdr->p_filesz);
111 + if (retval != NULL)
117 +/* First we validate the file by reading in the ELF header and checking
118 + the magic number. */
120 +static inline bfd_boolean
121 +elf_file_p (Elf64_External_Ehdr *x_ehdrp64)
123 + gdb_assert (sizeof (Elf64_External_Ehdr) >= sizeof (Elf32_External_Ehdr));
124 + gdb_assert (offsetof (Elf64_External_Ehdr, e_ident)
125 + == offsetof (Elf32_External_Ehdr, e_ident));
126 + gdb_assert (sizeof (((Elf64_External_Ehdr *) 0)->e_ident)
127 + == sizeof (((Elf32_External_Ehdr *) 0)->e_ident));
129 + return ((x_ehdrp64->e_ident[EI_MAG0] == ELFMAG0)
130 + && (x_ehdrp64->e_ident[EI_MAG1] == ELFMAG1)
131 + && (x_ehdrp64->e_ident[EI_MAG2] == ELFMAG2)
132 + && (x_ehdrp64->e_ident[EI_MAG3] == ELFMAG3));
135 +/* Translate an ELF file header in external format into an ELF file header in
136 + internal format. */
138 +#define H_GET_WORD(bfd, ptr) (is64 ? H_GET_64 (bfd, (ptr)) \
139 + : H_GET_32 (bfd, (ptr)))
140 +#define H_GET_SIGNED_WORD(bfd, ptr) (is64 ? H_GET_S64 (bfd, (ptr)) \
141 + : H_GET_S32 (bfd, (ptr)))
144 +elf_swap_ehdr_in (bfd *abfd,
145 + const Elf64_External_Ehdr *src64,
146 + Elf_Internal_Ehdr *dst)
148 + int is64 = bfd_get_arch_size (abfd) == 64;
149 +#define SRC(field) (is64 ? src64->field \
150 + : ((const Elf32_External_Ehdr *) src64)->field)
152 + int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
153 + memcpy (dst->e_ident, SRC (e_ident), EI_NIDENT);
154 + dst->e_type = H_GET_16 (abfd, SRC (e_type));
155 + dst->e_machine = H_GET_16 (abfd, SRC (e_machine));
156 + dst->e_version = H_GET_32 (abfd, SRC (e_version));
158 + dst->e_entry = H_GET_SIGNED_WORD (abfd, SRC (e_entry));
160 + dst->e_entry = H_GET_WORD (abfd, SRC (e_entry));
161 + dst->e_phoff = H_GET_WORD (abfd, SRC (e_phoff));
162 + dst->e_shoff = H_GET_WORD (abfd, SRC (e_shoff));
163 + dst->e_flags = H_GET_32 (abfd, SRC (e_flags));
164 + dst->e_ehsize = H_GET_16 (abfd, SRC (e_ehsize));
165 + dst->e_phentsize = H_GET_16 (abfd, SRC (e_phentsize));
166 + dst->e_phnum = H_GET_16 (abfd, SRC (e_phnum));
167 + dst->e_shentsize = H_GET_16 (abfd, SRC (e_shentsize));
168 + dst->e_shnum = H_GET_16 (abfd, SRC (e_shnum));
169 + dst->e_shstrndx = H_GET_16 (abfd, SRC (e_shstrndx));
174 +/* Translate an ELF program header table entry in external format into an
175 + ELF program header table entry in internal format. */
178 +elf_swap_phdr_in (bfd *abfd,
179 + const Elf64_External_Phdr *src64,
180 + Elf_Internal_Phdr *dst)
182 + int is64 = bfd_get_arch_size (abfd) == 64;
183 +#define SRC(field) (is64 ? src64->field \
184 + : ((const Elf32_External_Phdr *) src64)->field)
186 + int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
188 + dst->p_type = H_GET_32 (abfd, SRC (p_type));
189 + dst->p_flags = H_GET_32 (abfd, SRC (p_flags));
190 + dst->p_offset = H_GET_WORD (abfd, SRC (p_offset));
193 + dst->p_vaddr = H_GET_SIGNED_WORD (abfd, SRC (p_vaddr));
194 + dst->p_paddr = H_GET_SIGNED_WORD (abfd, SRC (p_paddr));
198 + dst->p_vaddr = H_GET_WORD (abfd, SRC (p_vaddr));
199 + dst->p_paddr = H_GET_WORD (abfd, SRC (p_paddr));
201 + dst->p_filesz = H_GET_WORD (abfd, SRC (p_filesz));
202 + dst->p_memsz = H_GET_WORD (abfd, SRC (p_memsz));
203 + dst->p_align = H_GET_WORD (abfd, SRC (p_align));
208 +#undef H_GET_SIGNED_WORD
211 +static Elf_Internal_Phdr *
212 +elf_get_phdr (bfd *templ, bfd_vma ehdr_vma, unsigned *e_phnum_pointer,
213 + bfd_vma *loadbase_pointer)
215 + /* sizeof (Elf64_External_Ehdr) >= sizeof (Elf32_External_Ehdr) */
216 + Elf64_External_Ehdr x_ehdr64; /* Elf file header, external form */
217 + Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */
218 + bfd_size_type x_phdrs_size;
219 + gdb_byte *x_phdrs_ptr;
220 + Elf_Internal_Phdr *i_phdrs;
226 + gdb_assert (templ != NULL);
227 + gdb_assert (sizeof (Elf64_External_Ehdr) >= sizeof (Elf32_External_Ehdr));
229 + /* Read in the ELF header in external format. */
230 + err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr64, sizeof x_ehdr64);
233 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
234 + warning (_("build-id: Error reading ELF header at address 0x%lx"),
235 + (unsigned long) ehdr_vma);
239 + /* Now check to see if we have a valid ELF file, and one that BFD can
240 + make use of. The magic number must match, the address size ('class')
241 + and byte-swapping must match our XVEC entry. */
243 + if (! elf_file_p (&x_ehdr64)
244 + || x_ehdr64.e_ident[EI_VERSION] != EV_CURRENT
245 + || !((bfd_get_arch_size (templ) == 64
246 + && x_ehdr64.e_ident[EI_CLASS] == ELFCLASS64)
247 + || (bfd_get_arch_size (templ) == 32
248 + && x_ehdr64.e_ident[EI_CLASS] == ELFCLASS32)))
250 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
251 + warning (_("build-id: Unrecognized ELF header at address 0x%lx"),
252 + (unsigned long) ehdr_vma);
256 + /* Check that file's byte order matches xvec's */
257 + switch (x_ehdr64.e_ident[EI_DATA])
259 + case ELFDATA2MSB: /* Big-endian */
260 + if (! bfd_header_big_endian (templ))
262 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
263 + warning (_("build-id: Unrecognized "
264 + "big-endian ELF header at address 0x%lx"),
265 + (unsigned long) ehdr_vma);
269 + case ELFDATA2LSB: /* Little-endian */
270 + if (! bfd_header_little_endian (templ))
272 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
273 + warning (_("build-id: Unrecognized "
274 + "little-endian ELF header at address 0x%lx"),
275 + (unsigned long) ehdr_vma);
279 + case ELFDATANONE: /* No data encoding specified */
280 + default: /* Unknown data encoding specified */
281 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
282 + warning (_("build-id: Unrecognized "
283 + "ELF header endianity at address 0x%lx"),
284 + (unsigned long) ehdr_vma);
288 + elf_swap_ehdr_in (templ, &x_ehdr64, &i_ehdr);
290 + /* The file header tells where to find the program headers.
291 + These are what we use to actually choose what to read. */
293 + if (i_ehdr.e_phentsize != (bfd_get_arch_size (templ) == 64
294 + ? sizeof (Elf64_External_Phdr)
295 + : sizeof (Elf32_External_Phdr))
296 + || i_ehdr.e_phnum == 0)
298 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
299 + warning (_("build-id: Invalid ELF program headers from the ELF header "
300 + "at address 0x%lx"), (unsigned long) ehdr_vma);
304 + x_phdrs_size = (bfd_get_arch_size (templ) == 64 ? sizeof (Elf64_External_Phdr)
305 + : sizeof (Elf32_External_Phdr));
307 + i_phdrs = (Elf_Internal_Phdr *) xmalloc (i_ehdr.e_phnum * (sizeof *i_phdrs + x_phdrs_size));
308 + x_phdrs_ptr = (gdb_byte *) &i_phdrs[i_ehdr.e_phnum];
309 + err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs_ptr,
310 + i_ehdr.e_phnum * x_phdrs_size);
314 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
315 + warning (_("build-id: Error reading "
316 + "ELF program headers at address 0x%lx"),
317 + (unsigned long) (ehdr_vma + i_ehdr.e_phoff));
321 + loadbase = ehdr_vma;
323 + for (i = 0; i < i_ehdr.e_phnum; ++i)
325 + elf_swap_phdr_in (templ, (Elf64_External_Phdr *)
326 + (x_phdrs_ptr + i * x_phdrs_size), &i_phdrs[i]);
327 + /* IA-64 vDSO may have two mappings for one segment, where one mapping
328 + is executable only, and one is read only. We must not use the
329 + executable one (PF_R is the first one, PF_X the second one). */
330 + if (i_phdrs[i].p_type == PT_LOAD && (i_phdrs[i].p_flags & PF_R))
332 + /* Only the first PT_LOAD segment indicates the file bias.
333 + Next segments may have P_VADDR arbitrarily higher.
334 + If the first segment has P_VADDR zero any next segment must not
335 + confuse us, the first one sets LOADBASE certainly enough. */
336 + if (!loadbase_set && i_phdrs[i].p_offset == 0)
338 + loadbase = ehdr_vma - i_phdrs[i].p_vaddr;
344 + if (build_id_verbose >= BUILD_ID_VERBOSE_BINARY_PARSE)
345 + warning (_("build-id: Found ELF header at address 0x%lx, loadbase 0x%lx"),
346 + (unsigned long) ehdr_vma, (unsigned long) loadbase);
348 + *e_phnum_pointer = i_ehdr.e_phnum;
349 + *loadbase_pointer = loadbase;
353 +/* BUILD_ID_ADDR_GET gets ADDR located somewhere in the object.
354 + Find the first section before ADDR containing an ELF header.
355 + We rely on the fact the sections from multiple files do not mix.
356 + FIXME: We should check ADDR is contained _inside_ the section with possibly
357 + missing content (P_FILESZ < P_MEMSZ). These omitted sections are currently
358 + hidden by _BFD_ELF_MAKE_SECTION_FROM_PHDR. */
360 +static CORE_ADDR build_id_addr;
361 +struct build_id_addr_sect
363 + struct build_id_addr_sect *next;
366 +static struct build_id_addr_sect *build_id_addr_sect;
368 +static void build_id_addr_candidate (bfd *abfd, asection *sect, void *obj)
370 + if (build_id_addr >= bfd_section_vma (abfd, sect))
372 + struct build_id_addr_sect *candidate;
374 + candidate = (struct build_id_addr_sect *) xmalloc (sizeof *candidate);
375 + candidate->next = build_id_addr_sect;
376 + build_id_addr_sect = candidate;
377 + candidate->sect = sect;
381 +struct bfd_build_id *
382 +build_id_addr_get (CORE_ADDR addr)
384 + struct build_id_addr_sect *candidate;
385 + struct bfd_build_id *retval = NULL;
386 + Elf_Internal_Phdr *i_phdr = NULL;
387 + bfd_vma loadbase = 0;
388 + unsigned e_phnum = 0;
390 + if (core_bfd == NULL)
393 + build_id_addr = addr;
394 + gdb_assert (build_id_addr_sect == NULL);
395 + bfd_map_over_sections (core_bfd, build_id_addr_candidate, NULL);
397 + /* Sections are sorted in the high-to-low VMAs order.
398 + Stop the search on the first ELF header we find.
399 + Do not continue the search even if it does not contain NT_GNU_BUILD_ID. */
401 + for (candidate = build_id_addr_sect; candidate != NULL;
402 + candidate = candidate->next)
404 + i_phdr = elf_get_phdr (core_bfd,
405 + bfd_section_vma (core_bfd, candidate->sect),
406 + &e_phnum, &loadbase);
407 + if (i_phdr != NULL)
411 + if (i_phdr != NULL)
413 + retval = build_id_phdr_get (core_bfd, loadbase, e_phnum, i_phdr);
417 + while (build_id_addr_sect != NULL)
419 + candidate = build_id_addr_sect;
420 + build_id_addr_sect = candidate->next;
427 /* See build-id.h. */
430 @@ -50,7 +448,7 @@ build_id_verify (bfd *abfd, size_t check_len, const bfd_byte *check)
431 const struct bfd_build_id *found;
434 - found = build_id_bfd_get (abfd);
435 + found = build_id_bfd_shdr_get (abfd);
438 warning (_("File \"%s\" has no build-id, file skipped"),
439 @@ -65,11 +463,50 @@ build_id_verify (bfd *abfd, size_t check_len, const bfd_byte *check)
444 +link_resolve (const char *symlink, int level)
446 + char buf[PATH_MAX + 1], *target, *retval;
450 + return xstrdup (symlink);
452 + got = readlink (symlink, buf, sizeof (buf));
453 + if (got < 0 || got >= sizeof (buf))
454 + return xstrdup (symlink);
457 + if (IS_ABSOLUTE_PATH (buf))
458 + target = xstrdup (buf);
461 + const std::string dir (ldirname (symlink));
463 + target = xstrprintf ("%s"
464 +#ifndef HAVE_DOS_BASED_FILE_SYSTEM
466 +#else /* HAVE_DOS_BASED_FILE_SYSTEM */
468 +#endif /* HAVE_DOS_BASED_FILE_SYSTEM */
469 + "%s", dir.c_str(), buf);
472 + retval = link_resolve (target, level + 1);
477 /* See build-id.h. */
480 -build_id_to_debug_bfd (size_t build_id_len, const bfd_byte *build_id)
481 +build_id_to_debug_bfd (size_t build_id_len, const bfd_byte *build_id,
482 + char **link_return, int add_debug_suffix)
485 + std::string link, link_all;
486 + struct cleanup *back_to;
488 gdb_bfd_ref_ptr abfd;
490 /* Keep backward compatibility so that DEBUG_FILE_DIRECTORY being "" will
491 @@ -82,63 +519,296 @@ build_id_to_debug_bfd (size_t build_id_len, const bfd_byte *build_id)
493 const gdb_byte *data = build_id;
494 size_t size = build_id_len;
495 + char *filename = NULL;
496 + struct cleanup *inner;
498 + struct stat statbuf_trash;
501 - std::string link = debugdir.get ();
502 + link = debugdir.get ();
503 link += "/.build-id/";
508 - string_appendf (link, "%02x/", (unsigned) *data++);
509 + string_appendf (link, "%02x", (unsigned) *data++);
515 string_appendf (link, "%02x", (unsigned) *data++);
519 if (separate_debug_file_debug)
520 printf_unfiltered (_(" Trying %s\n"), link.c_str ());
522 - /* lrealpath() is expensive even for the usually non-existent files. */
523 - gdb::unique_xmalloc_ptr<char> filename;
524 - if (access (link.c_str (), F_OK) == 0)
525 - filename.reset (lrealpath (link.c_str ()));
527 - if (filename == NULL)
529 + for (seqno = 0;; seqno++)
533 + /* There can be multiple build-id symlinks pointing to real files
534 + with the same build-id (such as hard links). Some of the real
535 + files may not be installed. */
537 + string_appendf (link, ".%u", seqno);
540 + if (add_debug_suffix)
545 + /* If none of the real files is found report as missing file
546 + always the non-.%u-suffixed file. */
550 + /* `access' automatically dereferences LINK. */
551 + if (lstat (link.c_str (), &statbuf_trash) != 0)
553 + /* Stop increasing SEQNO. */
557 + filename = lrealpath (link.c_str ());
558 + if (filename == NULL)
561 + /* We expect to be silent on the non-existing files. */
562 + inner = make_cleanup (xfree, filename);
563 + abfd = gdb_bfd_open (filename, gnutarget, -1);
564 + do_cleanups (inner);
569 + if (build_id_verify (abfd.get(), build_id_len, build_id))
577 - /* We expect to be silent on the non-existing files. */
578 - abfd = gdb_bfd_open (filename.get (), gnutarget, -1);
579 + if (filename != NULL)
581 + /* LINK_ALL is not used below in this non-NULL FILENAME case. */
587 + /* If the symlink has target request to install the target.
588 + BASE-debuginfo.rpm contains the symlink but BASE.rpm may be missing.
589 + https://bugzilla.redhat.com/show_bug.cgi?id=981154 */
590 + std::string link0_resolved (link_resolve (link0.c_str (), 0));
592 - if (build_id_verify (abfd.get(), build_id_len, build_id))
594 + if (link_all.empty ())
595 + link_all = link0_resolved;
598 + /* Use whitespace instead of DIRNAME_SEPARATOR to be compatible with
599 + its possible use as an argument for installation command. */
600 + link_all += " " + link0_resolved;
605 + if (link_return != NULL)
609 + *link_return = xstrdup (link.c_str ());
613 + *link_return = xstrdup (link_all.c_str ());
621 +build_id_to_filename (const struct bfd_build_id *build_id, char **link_return)
623 + gdb_bfd_ref_ptr abfd;
626 + abfd = build_id_to_debug_bfd (build_id->size, build_id->data, link_return, 0);
630 + result = xstrdup (bfd_get_filename (abfd));
635 +/* This MISSING_FILEPAIR_HASH tracker is used only for the duplicite messages
636 + Try to install the hash file ...
639 +struct missing_filepair
646 +static struct htab *missing_filepair_hash;
647 +static struct obstack missing_filepair_obstack;
650 +missing_filepair_xcalloc (size_t nmemb, size_t nmemb_size)
653 + size_t size = nmemb * nmemb_size;
655 + retval = obstack_alloc (&missing_filepair_obstack, size);
656 + memset (retval, 0, size);
661 +missing_filepair_hash_func (const struct missing_filepair *elem)
663 + hashval_t retval = 0;
665 + retval ^= htab_hash_string (elem->binary);
666 + if (elem->debug != NULL)
667 + retval ^= htab_hash_string (elem->debug);
673 +missing_filepair_eq (const struct missing_filepair *elem1,
674 + const struct missing_filepair *elem2)
676 + return strcmp (elem1->binary, elem2->binary) == 0
677 + && ((elem1->debug == NULL) == (elem2->debug == NULL))
678 + && (elem1->debug == NULL || strcmp (elem1->debug, elem2->debug) == 0);
682 +missing_filepair_change (void)
684 + if (missing_filepair_hash != NULL)
686 + obstack_free (&missing_filepair_obstack, NULL);
687 + /* All their memory came just from missing_filepair_OBSTACK. */
688 + missing_filepair_hash = NULL;
693 +debug_print_executable_changed (void)
695 + missing_filepair_change ();
698 +/* Notify user the file BINARY with (possibly NULL) associated separate debug
699 + information file DEBUG is missing. DEBUG may or may not be the build-id
700 + file such as would be:
701 + /usr/lib/debug/.build-id/dd/b1d2ce632721c47bb9e8679f369e2295ce71be.debug
705 +debug_print_missing (const char *binary, const char *debug)
707 + size_t binary_len0 = strlen (binary) + 1;
708 + size_t debug_len0 = debug ? strlen (debug) + 1 : 0;
709 + struct missing_filepair missing_filepair_find;
710 + struct missing_filepair *missing_filepair;
711 + struct missing_filepair **slot;
713 + if (build_id_verbose < BUILD_ID_VERBOSE_FILENAMES)
716 + if (missing_filepair_hash == NULL)
718 + obstack_init (&missing_filepair_obstack);
719 + missing_filepair_hash = htab_create_alloc (64,
720 + (hashval_t (*) (const void *)) missing_filepair_hash_func,
721 + (int (*) (const void *, const void *)) missing_filepair_eq, NULL,
722 + missing_filepair_xcalloc, NULL);
725 + /* Use MISSING_FILEPAIR_FIND first instead of calling obstack_alloc with
726 + obstack_free in the case of a (rare) match. The problem is ALLOC_F for
727 + MISSING_FILEPAIR_HASH allocates from MISSING_FILEPAIR_OBSTACK maintenance
728 + structures for MISSING_FILEPAIR_HASH. Calling obstack_free would possibly
729 + not to free only MISSING_FILEPAIR but also some such structures (allocated
730 + during the htab_find_slot call). */
732 + missing_filepair_find.binary = (char *) binary;
733 + missing_filepair_find.debug = (char *) debug;
734 + slot = (struct missing_filepair **) htab_find_slot (missing_filepair_hash,
735 + &missing_filepair_find,
738 + /* While it may be still printed duplicitely with the missing debuginfo file
739 + * it is due to once printing about the binary file build-id link and once
740 + * about the .debug file build-id link as both the build-id symlinks are
741 + * located in the debuginfo package. */
746 + missing_filepair = (struct missing_filepair *) obstack_alloc (&missing_filepair_obstack,
747 + sizeof (*missing_filepair) - 1
748 + + binary_len0 + debug_len0);
749 + missing_filepair->binary = missing_filepair->data;
750 + memcpy (missing_filepair->binary, binary, binary_len0);
753 + missing_filepair->debug = missing_filepair->binary + binary_len0;
754 + memcpy (missing_filepair->debug, debug, debug_len0);
757 + missing_filepair->debug = NULL;
759 + *slot = missing_filepair;
761 + /* We do not collect and flush these messages as each such message
762 + already requires its own separate lines. */
764 + fprintf_unfiltered (gdb_stdlog,
765 + _("Missing separate debuginfo for %s\n"), binary);
767 + fprintf_unfiltered (gdb_stdlog, _("Try to install the hash file %s\n"),
771 /* See build-id.h. */
774 -find_separate_debug_file_by_buildid (struct objfile *objfile)
775 +find_separate_debug_file_by_buildid (struct objfile *objfile,
776 + gdb::unique_xmalloc_ptr<char> *build_id_filename_return)
778 const struct bfd_build_id *build_id;
780 - build_id = build_id_bfd_get (objfile->obfd);
781 + if (build_id_filename_return)
782 + *build_id_filename_return = NULL;
784 + build_id = build_id_bfd_shdr_get (objfile->obfd);
785 if (build_id != NULL)
787 if (separate_debug_file_debug)
788 printf_unfiltered (_("\nLooking for separate debug info (build-id) for "
789 "%s\n"), objfile_name (objfile));
791 + char *build_id_filename_cstr = NULL;
792 gdb_bfd_ref_ptr abfd (build_id_to_debug_bfd (build_id->size,
795 + (!build_id_filename_return ? NULL : &build_id_filename_cstr), 1));
796 + if (build_id_filename_return)
798 + if (!build_id_filename_cstr)
799 + gdb_assert (!*build_id_filename_return);
802 + *build_id_filename_return = gdb::unique_xmalloc_ptr<char> (build_id_filename_cstr);
803 + build_id_filename_cstr = NULL;
807 /* Prevent looping on a stripped .debug file. */
809 && filename_cmp (bfd_get_filename (abfd.get ()),
810 @@ -151,3 +821,21 @@ find_separate_debug_file_by_buildid (struct objfile *objfile)
812 return std::string ();
815 +extern void _initialize_build_id (void);
818 +_initialize_build_id (void)
820 + add_setshow_zinteger_cmd ("build-id-verbose", no_class, &build_id_verbose,
822 +Set debugging level of the build-id locator."), _("\
823 +Show debugging level of the build-id locator."), _("\
824 +Level 1 (default) enables printing the missing debug filenames,\n\
825 +level 2 also prints the parsing of binaries to find the identificators."),
827 + show_build_id_verbose,
828 + &setlist, &showlist);
830 + gdb::observers::executable_changed.attach (debug_print_executable_changed);
832 diff --git a/gdb/build-id.h b/gdb/build-id.h
839 -/* Locate NT_GNU_BUILD_ID from ABFD and return its content. */
840 +/* Separate debuginfo files have corrupted PHDR but SHDR is correct there.
841 + Locate NT_GNU_BUILD_ID from ABFD and return its content. */
843 -extern const struct bfd_build_id *build_id_bfd_get (bfd *abfd);
844 +extern const struct bfd_build_id *build_id_bfd_shdr_get (bfd *abfd);
846 /* Return true if ABFD has NT_GNU_BUILD_ID matching the CHECK value.
847 Otherwise, issue a warning and return false. */
848 @@ -38,13 +39,18 @@ extern int build_id_verify (bfd *abfd,
851 extern gdb_bfd_ref_ptr build_id_to_debug_bfd (size_t build_id_len,
852 - const bfd_byte *build_id);
853 + const bfd_byte *build_id,
854 + char **link_return,
855 + int add_debug_suffix);
857 +extern char *build_id_to_filename (const struct bfd_build_id *build_id,
858 + char **link_return);
860 /* Find the separate debug file for OBJFILE, by using the build-id
861 associated with OBJFILE's BFD. If successful, returns the file name for the
862 separate debug file, otherwise, return an empty string. */
864 -extern std::string find_separate_debug_file_by_buildid
865 - (struct objfile *objfile);
866 +extern std::string find_separate_debug_file_by_buildid (struct objfile *objfile,
867 + gdb::unique_xmalloc_ptr<char> *build_id_filename_return);
869 #endif /* BUILD_ID_H */
870 diff --git a/gdb/coffread.c b/gdb/coffread.c
873 @@ -733,7 +733,8 @@ coff_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
874 /* Try to add separate debug file if no symbols table found. */
875 if (!objfile_has_partial_symbols (objfile))
877 - std::string debugfile = find_separate_debug_file_by_buildid (objfile);
878 + std::string debugfile = find_separate_debug_file_by_buildid (objfile,
881 if (debugfile.empty ())
882 debugfile = find_separate_debug_file_by_debuglink (objfile);
883 diff --git a/gdb/corelow.c b/gdb/corelow.c
888 #include "completer.h"
889 #include "filestuff.h"
891 +#include "elf/common.h"
893 +#include "build-id.h"
896 #define O_LARGEFILE 0
897 @@ -321,6 +325,54 @@ add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg)
898 inferior_ptid = ptid; /* Yes, make it current. */
901 +static int build_id_core_loads = 1;
904 +build_id_locate_exec (int from_tty)
906 + CORE_ADDR at_entry;
907 + struct bfd_build_id *build_id;
908 + char *execfilename, *debug_filename;
909 + char *build_id_filename;
910 + struct cleanup *back_to;
912 + if (exec_bfd != NULL || symfile_objfile != NULL)
915 + if (target_auxv_search (current_top_target (), AT_ENTRY, &at_entry) <= 0)
918 + build_id = build_id_addr_get (at_entry);
919 + if (build_id == NULL)
921 + back_to = make_cleanup (xfree, build_id);
923 + /* SYMFILE_OBJFILE should refer to the main executable (not only to its
924 + separate debug info file). gcc44+ keeps .eh_frame only in the main
925 + executable without its duplicate .debug_frame in the separate debug info
926 + file - such .eh_frame would not be found if SYMFILE_OBJFILE would refer
927 + directly to the separate debug info file. */
929 + execfilename = build_id_to_filename (build_id, &build_id_filename);
930 + make_cleanup (xfree, build_id_filename);
932 + if (execfilename != NULL)
934 + make_cleanup (xfree, execfilename);
935 + exec_file_attach (execfilename, from_tty);
936 + symbol_file_add_main (execfilename,
937 + symfile_add_flag (!from_tty ? 0 : SYMFILE_VERBOSE));
938 + if (symfile_objfile != NULL)
939 + symfile_objfile->flags |= OBJF_BUILD_ID_CORE_LOADED;
942 + debug_print_missing (_("the main executable file"), build_id_filename);
944 + do_cleanups (back_to);
946 + /* No automatic SOLIB_ADD as the libraries would get read twice. */
949 /* Issue a message saying we have no core to debug, if FROM_TTY. */
952 @@ -464,6 +516,14 @@ core_target_open (const char *arg, int from_tty)
953 switch_to_thread (thread);
956 + /* Find the build_id identifiers. If it gets executed after
957 + POST_CREATE_INFERIOR we would clash with asking to discard the already
958 + loaded VDSO symbols. If it gets executed before bfd_map_over_sections
959 + INFERIOR_PTID is still not set and libthread_db initialization crashes on
960 + PID == 0 in ps_pglobal_lookup. */
961 + if (build_id_core_loads != 0)
962 + build_id_locate_exec (from_tty);
964 post_create_inferior (target, from_tty);
966 /* Now go through the target stack looking for threads since there
967 @@ -1072,4 +1132,11 @@ void
968 _initialize_corelow (void)
970 add_target (core_target_info, core_target_open, filename_completer);
972 + add_setshow_boolean_cmd ("build-id-core-loads", class_files,
973 + &build_id_core_loads, _("\
974 +Set whether CORE-FILE loads the build-id associated files automatically."), _("\
975 +Show whether CORE-FILE loads the build-id associated files automatically."),
977 + &setlist, &showlist);
979 diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
980 --- a/gdb/doc/gdb.texinfo
981 +++ b/gdb/doc/gdb.texinfo
982 @@ -19570,6 +19570,27 @@ information files.
986 +You can also adjust the current verbosity of the @dfn{build id} locating.
990 +@kindex set build-id-verbose
991 +@item set build-id-verbose 0
992 +No additional messages are printed.
994 +@item set build-id-verbose 1
995 +Missing separate debug filenames are printed.
997 +@item set build-id-verbose 2
998 +Missing separate debug filenames are printed and also all the parsing of the
999 +binaries to find their @dfn{build id} content is printed.
1001 +@kindex show build-id-verbose
1002 +@item show build-id-verbose
1003 +Show the current verbosity value for the @dfn{build id} content locating.
1007 @cindex @code{.gnu_debuglink} sections
1008 @cindex debug link sections
1009 A debug link is a special section of the executable file named
1010 diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
1011 --- a/gdb/dwarf2read.c
1012 +++ b/gdb/dwarf2read.c
1013 @@ -2683,7 +2683,7 @@ dwarf2_get_dwz_file (struct dwarf2_per_objfile *dwarf2_per_objfile)
1016 if (dwz_bfd == NULL)
1017 - dwz_bfd = build_id_to_debug_bfd (buildid_len, buildid);
1018 + dwz_bfd = build_id_to_debug_bfd (buildid_len, buildid, NULL, 1);
1020 if (dwz_bfd == NULL)
1021 error (_("could not find '.gnu_debugaltlink' file for %s"),
1022 diff --git a/gdb/elfread.c b/gdb/elfread.c
1025 @@ -1290,7 +1290,9 @@ elf_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
1026 && objfile->separate_debug_objfile == NULL
1027 && objfile->separate_debug_objfile_backlink == NULL)
1029 - std::string debugfile = find_separate_debug_file_by_buildid (objfile);
1030 + gdb::unique_xmalloc_ptr<char> build_id_filename;
1031 + std::string debugfile
1032 + = find_separate_debug_file_by_buildid (objfile, &build_id_filename);
1034 if (debugfile.empty ())
1035 debugfile = find_separate_debug_file_by_debuglink (objfile);
1036 @@ -1302,6 +1304,10 @@ elf_symfile_read (struct objfile *objfile, symfile_add_flags symfile_flags)
1037 symbol_file_add_separate (abfd.get (), debugfile.c_str (),
1038 symfile_flags, objfile);
1040 + /* Check if any separate debug info has been extracted out. */
1041 + else if (bfd_get_section_by_name (objfile->obfd, ".gnu_debuglink")
1043 + debug_print_missing (objfile_name (objfile), build_id_filename.get ());
1047 diff --git a/gdb/objfiles.h b/gdb/objfiles.h
1048 --- a/gdb/objfiles.h
1049 +++ b/gdb/objfiles.h
1050 @@ -470,6 +470,10 @@ struct objfile
1051 htab_t static_links {};
1054 +/* This file was loaded according to the BUILD_ID_CORE_LOADS rules. */
1056 +#define OBJF_BUILD_ID_CORE_LOADED static_cast<enum objfile_flag>(1 << 12)
1058 /* Declarations for functions defined in objfiles.c */
1060 extern struct gdbarch *get_objfile_arch (const struct objfile *);
1061 diff --git a/gdb/python/py-objfile.c b/gdb/python/py-objfile.c
1062 --- a/gdb/python/py-objfile.c
1063 +++ b/gdb/python/py-objfile.c
1064 @@ -137,7 +137,7 @@ objfpy_get_build_id (PyObject *self, void *closure)
1068 - build_id = build_id_bfd_get (objfile->obfd);
1069 + build_id = build_id_bfd_shdr_get (objfile->obfd);
1071 CATCH (except, RETURN_MASK_ALL)
1073 @@ -544,7 +544,7 @@ objfpy_lookup_objfile_by_build_id (const char *build_id)
1074 /* Don't return separate debug files. */
1075 if (objfile->separate_debug_objfile_backlink != NULL)
1077 - obfd_build_id = build_id_bfd_get (objfile->obfd);
1078 + obfd_build_id = build_id_bfd_shdr_get (objfile->obfd);
1079 if (obfd_build_id == NULL)
1081 if (objfpy_build_id_matches (obfd_build_id, build_id))
1082 diff --git a/gdb/solib-svr4.c b/gdb/solib-svr4.c
1083 --- a/gdb/solib-svr4.c
1084 +++ b/gdb/solib-svr4.c
1087 #include "gdb_bfd.h"
1089 +#include "build-id.h"
1091 static struct link_map_offsets *svr4_fetch_link_map_offsets (void);
1092 static int svr4_have_link_map_offsets (void);
1093 @@ -1356,9 +1357,51 @@ svr4_read_so_list (CORE_ADDR lm, CORE_ADDR prev_lm,
1097 - strncpy (newobj->so_name, buffer.get (), SO_NAME_MAX_PATH_SIZE - 1);
1098 - newobj->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
1099 - strcpy (newobj->so_original_name, newobj->so_name);
1101 + struct bfd_build_id *build_id;
1103 + strncpy (newobj->so_original_name, buffer.get (), SO_NAME_MAX_PATH_SIZE - 1);
1104 + newobj->so_original_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
1105 + /* May get overwritten below. */
1106 + strcpy (newobj->so_name, newobj->so_original_name);
1108 + build_id = build_id_addr_get (((lm_info_svr4 *) newobj->lm_info)->l_ld);
1109 + if (build_id != NULL)
1111 + char *name, *build_id_filename;
1113 + /* Missing the build-id matching separate debug info file
1114 + would be handled while SO_NAME gets loaded. */
1115 + name = build_id_to_filename (build_id, &build_id_filename);
1118 + strncpy (newobj->so_name, name, SO_NAME_MAX_PATH_SIZE - 1);
1119 + newobj->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
1124 + debug_print_missing (newobj->so_name, build_id_filename);
1126 + /* In the case the main executable was found according to
1127 + its build-id (from a core file) prevent loading
1128 + a different build of a library with accidentally the
1131 + It suppresses bogus backtraces (and prints "??" there
1132 + instead) if the on-disk files no longer match the
1133 + running program version. */
1135 + if (symfile_objfile != NULL
1136 + && (symfile_objfile->flags
1137 + & OBJF_BUILD_ID_CORE_LOADED) != 0)
1138 + newobj->so_name[0] = 0;
1141 + xfree (build_id_filename);
1146 /* If this entry has no name, or its name matches the name
1147 for the main executable, don't include it in the list. */
1148 diff --git a/gdb/symfile.h b/gdb/symfile.h
1151 @@ -537,6 +537,10 @@ void expand_symtabs_matching
1152 void map_symbol_filenames (symbol_filename_ftype *fun, void *data,
1155 +/* build-id support. */
1156 +extern struct bfd_build_id *build_id_addr_get (CORE_ADDR addr);
1157 +extern void debug_print_missing (const char *binary, const char *debug);
1159 /* From dwarf2read.c */
1161 /* Names for a dwarf2 debugging section. The field NORMAL is the normal
1162 diff --git a/gdb/testsuite/gdb.base/corefile.exp b/gdb/testsuite/gdb.base/corefile.exp
1163 --- a/gdb/testsuite/gdb.base/corefile.exp
1164 +++ b/gdb/testsuite/gdb.base/corefile.exp
1165 @@ -311,3 +311,33 @@ gdb_test_multiple "core-file $corefile" $test {
1171 +# Test auto-loading of binary files through build-id from the core file.
1172 +set buildid [build_id_debug_filename_get $binfile]
1173 +set wholetest "binfile found by build-id"
1174 +if {$buildid == ""} {
1175 + untested "$wholetest (binary has no build-id)"
1180 + regsub {\.debug$} $buildid {} buildid
1181 + set debugdir [standard_output_file ${testfile}-debugdir]
1182 + file delete -force -- $debugdir
1183 + file mkdir $debugdir/[file dirname $buildid]
1184 + file copy $binfile $debugdir/$buildid
1186 + set test "show debug-file-directory"
1187 + gdb_test_multiple $test $test {
1188 + -re "The directory where separate debug symbols are searched for is \"(.*)\"\\.\r\n$gdb_prompt $" {
1189 + set debugdir_orig $expect_out(1,string)
1193 + gdb_test_no_output "set debug-file-directory $debugdir:$debugdir_orig" "set debug-file-directory"
1194 + gdb_test "show build-id-core-loads" {Whether CORE-FILE loads the build-id associated files automatically is on\.}
1195 + gdb_test "core-file $corefile" "\r\nProgram terminated with .*" "core-file without executable"
1196 + gdb_test "info files" "Local exec file:\r\n\[ \t\]*`[string_to_regexp $debugdir/$buildid]', file type .*"
1199 diff --git a/gdb/testsuite/gdb.base/new-ui-pending-input.exp b/gdb/testsuite/gdb.base/new-ui-pending-input.exp
1200 --- a/gdb/testsuite/gdb.base/new-ui-pending-input.exp
1201 +++ b/gdb/testsuite/gdb.base/new-ui-pending-input.exp
1202 @@ -62,6 +62,7 @@ proc test_command_line_new_ui_pending_input {} {
1204 append options " -iex \"set height 0\""
1205 append options " -iex \"set width 0\""
1206 + append options " -iex \"set build-id-verbose 0\""
1207 append options " -iex \"new-ui console $extra_tty_name\""
1208 append options " -ex \"b $bpline\""
1209 append options " -ex \"run\""
1210 diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
1211 --- a/gdb/testsuite/lib/gdb.exp
1212 +++ b/gdb/testsuite/lib/gdb.exp
1213 @@ -1695,6 +1695,16 @@ proc default_gdb_start { } {
1214 warning "Couldn't set the width to 0."
1217 + # Turn off the missing warnings as the testsuite does not expect it.
1218 + send_gdb "set build-id-verbose 0\n"
1220 + -re "$gdb_prompt $" {
1221 + verbose "Disabled the missing debug infos warnings." 2
1224 + warning "Could not disable the missing debug infos warnings.."
1230 diff --git a/gdb/testsuite/lib/mi-support.exp b/gdb/testsuite/lib/mi-support.exp
1231 --- a/gdb/testsuite/lib/mi-support.exp
1232 +++ b/gdb/testsuite/lib/mi-support.exp
1233 @@ -309,6 +309,16 @@ proc default_mi_gdb_start { args } {
1234 warning "Couldn't set the width to 0."
1237 + # Turn off the missing warnings as the testsuite does not expect it.
1238 + send_gdb "190-gdb-set build-id-verbose 0\n"
1240 + -re ".*190-gdb-set build-id-verbose 0\r\n190\\\^done\r\n$mi_gdb_prompt$" {
1241 + verbose "Disabled the missing debug infos warnings." 2
1244 + warning "Could not disable the missing debug infos warnings.."
1248 if { $separate_inferior_pty } {
1249 mi_create_inferior_pty