1 /* ELF emulation code for targets using elf.em.
2 Copyright (C) 1991-2020 Free Software Foundation, Inc.
4 This file is part of the GNU Binutils.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
23 #include "libiberty.h"
24 #include "filenames.h"
25 #include "safe-ctype.h"
35 #include "ldbuildid.h"
49 /* Style of .note.gnu.build-id section. */
50 const char *ldelf_emit_note_gnu_build_id
;
52 /* These variables are required to pass information back and forth
53 between after_open and check_needed and stat_needed and vercheck. */
55 static struct bfd_link_needed_list
*global_needed
;
56 static lang_input_statement_type
*global_found
;
57 static struct stat global_stat
;
58 static struct bfd_link_needed_list
*global_vercheck_needed
;
59 static bfd_boolean global_vercheck_failed
;
62 ldelf_after_parse (void)
64 if (bfd_link_pie (&link_info
))
65 link_info
.flags_1
|= (bfd_vma
) DF_1_PIE
;
67 if (bfd_link_executable (&link_info
)
68 && link_info
.nointerp
)
70 if (link_info
.dynamic_undefined_weak
> 0)
71 einfo (_("%P: warning: -z dynamic-undefined-weak ignored\n"));
72 link_info
.dynamic_undefined_weak
= 0;
74 after_parse_default ();
77 /* Handle the generation of DT_NEEDED tags. */
80 ldelf_load_symbols (lang_input_statement_type
*entry
)
84 /* Tell the ELF linker that we don't want the output file to have a
85 DT_NEEDED entry for this file, unless it is used to resolve
86 references in a regular object. */
87 if (entry
->flags
.add_DT_NEEDED_for_regular
)
88 link_class
= DYN_AS_NEEDED
;
90 /* Tell the ELF linker that we don't want the output file to have a
91 DT_NEEDED entry for any dynamic library in DT_NEEDED tags from
93 if (!entry
->flags
.add_DT_NEEDED_for_dynamic
)
94 link_class
|= DYN_NO_ADD_NEEDED
;
96 if (entry
->flags
.just_syms
97 && (bfd_get_file_flags (entry
->the_bfd
) & DYNAMIC
) != 0)
98 einfo (_("%F%P: %pB: --just-symbols may not be used on DSO\n"),
102 || (bfd_get_file_flags (entry
->the_bfd
) & DYNAMIC
) == 0)
105 bfd_elf_set_dyn_lib_class (entry
->the_bfd
,
106 (enum dynamic_lib_link_class
) link_class
);
108 /* Continue on with normal load_symbols processing. */
112 /* On Linux, it's possible to have different versions of the same
113 shared library linked against different versions of libc. The
114 dynamic linker somehow tags which libc version to use in
115 /etc/ld.so.cache, and, based on the libc that it sees in the
116 executable, chooses which version of the shared library to use.
118 We try to do a similar check here by checking whether this shared
119 library needs any other shared libraries which may conflict with
120 libraries we have already included in the link. If it does, we
121 skip it, and try to find another shared library farther on down the
124 This is called via lang_for_each_input_file.
125 GLOBAL_VERCHECK_NEEDED is the list of objects needed by the object
126 which we are checking. This sets GLOBAL_VERCHECK_FAILED if we find
127 a conflicting version. */
130 ldelf_vercheck (lang_input_statement_type
*s
)
133 struct bfd_link_needed_list
*l
;
135 if (global_vercheck_failed
)
137 if (s
->the_bfd
== NULL
138 || (bfd_get_file_flags (s
->the_bfd
) & DYNAMIC
) == 0)
141 soname
= bfd_elf_get_dt_soname (s
->the_bfd
);
143 soname
= lbasename (bfd_get_filename (s
->the_bfd
));
145 for (l
= global_vercheck_needed
; l
!= NULL
; l
= l
->next
)
149 if (filename_cmp (soname
, l
->name
) == 0)
151 /* Probably can't happen, but it's an easy check. */
155 if (strchr (l
->name
, '/') != NULL
)
158 suffix
= strstr (l
->name
, ".so.");
162 suffix
+= sizeof ".so." - 1;
164 if (filename_ncmp (soname
, l
->name
, suffix
- l
->name
) == 0)
166 /* Here we know that S is a dynamic object FOO.SO.VER1, and
167 the object we are considering needs a dynamic object
168 FOO.SO.VER2, and VER1 and VER2 are different. This
169 appears to be a version mismatch, so we tell the caller
170 to try a different version of this library. */
171 global_vercheck_failed
= TRUE
;
178 /* See if an input file matches a DT_NEEDED entry by running stat on
182 ldelf_stat_needed (lang_input_statement_type
*s
)
188 if (global_found
!= NULL
)
190 if (s
->the_bfd
== NULL
)
193 /* If this input file was an as-needed entry, and wasn't found to be
194 needed at the stage it was linked, then don't say we have loaded it. */
195 if ((bfd_elf_get_dyn_lib_class (s
->the_bfd
) & DYN_AS_NEEDED
) != 0)
198 if (bfd_stat (s
->the_bfd
, &st
) != 0)
200 einfo (_("%P: %pB: bfd_stat failed: %E\n"), s
->the_bfd
);
204 /* Some operating systems, e.g. Windows, do not provide a meaningful
205 st_ino; they always set it to zero. (Windows does provide a
206 meaningful st_dev.) Do not indicate a duplicate library in that
207 case. While there is no guarantee that a system that provides
208 meaningful inode numbers will never set st_ino to zero, this is
209 merely an optimization, so we do not need to worry about false
211 if (st
.st_dev
== global_stat
.st_dev
212 && st
.st_ino
== global_stat
.st_ino
219 /* We issue a warning if it looks like we are including two
220 different versions of the same shared library. For example,
221 there may be a problem if -lc picks up libc.so.6 but some other
222 shared library has a DT_NEEDED entry of libc.so.5. This is a
223 heuristic test, and it will only work if the name looks like
224 NAME.so.VERSION. FIXME: Depending on file names is error-prone.
225 If we really want to issue warnings about mixing version numbers
226 of shared libraries, we need to find a better way. */
228 if (strchr (global_needed
->name
, '/') != NULL
)
230 suffix
= strstr (global_needed
->name
, ".so.");
233 suffix
+= sizeof ".so." - 1;
235 soname
= bfd_elf_get_dt_soname (s
->the_bfd
);
237 soname
= lbasename (s
->filename
);
239 if (filename_ncmp (soname
, global_needed
->name
,
240 suffix
- global_needed
->name
) == 0)
241 einfo (_("%P: warning: %s, needed by %pB, may conflict with %s\n"),
242 global_needed
->name
, global_needed
->by
, soname
);
245 /* This function is called for each possible name for a dynamic object
246 named by a DT_NEEDED entry. The FORCE parameter indicates whether
247 to skip the check for a conflicting version. */
250 ldelf_try_needed (struct dt_needed
*needed
, int force
, int is_linux
)
253 const char *name
= needed
->name
;
257 abfd
= bfd_openr (name
, bfd_get_target (link_info
.output_bfd
));
261 info_msg (_("attempt to open %s failed\n"), name
);
265 track_dependency_files (name
);
267 /* Linker needs to decompress sections. */
268 abfd
->flags
|= BFD_DECOMPRESS
;
270 if (! bfd_check_format (abfd
, bfd_object
))
275 if ((bfd_get_file_flags (abfd
) & DYNAMIC
) == 0)
281 /* For DT_NEEDED, they have to match. */
282 if (abfd
->xvec
!= link_info
.output_bfd
->xvec
)
288 /* Check whether this object would include any conflicting library
289 versions. If FORCE is set, then we skip this check; we use this
290 the second time around, if we couldn't find any compatible
291 instance of the shared library. */
295 struct bfd_link_needed_list
*needs
;
297 if (! bfd_elf_get_bfd_needed_list (abfd
, &needs
))
298 einfo (_("%F%P: %pB: bfd_elf_get_bfd_needed_list failed: %E\n"), abfd
);
302 global_vercheck_needed
= needs
;
303 global_vercheck_failed
= FALSE
;
304 lang_for_each_input_file (ldelf_vercheck
);
305 if (global_vercheck_failed
)
308 /* Return FALSE to force the caller to move on to try
309 another file on the search path. */
313 /* But wait! It gets much worse. On Linux, if a shared
314 library does not use libc at all, we are supposed to skip
315 it the first time around in case we encounter a shared
316 library later on with the same name which does use the
317 version of libc that we want. This is much too horrible
318 to use on any system other than Linux. */
321 struct bfd_link_needed_list
*l
;
323 for (l
= needs
; l
!= NULL
; l
= l
->next
)
324 if (CONST_STRNEQ (l
->name
, "libc.so"))
335 /* We've found a dynamic object matching the DT_NEEDED entry. */
337 /* We have already checked that there is no other input file of the
338 same name. We must now check again that we are not including the
339 same file twice. We need to do this because on many systems
340 libc.so is a symlink to, e.g., libc.so.1. The SONAME entry will
341 reference libc.so.1. If we have already included libc.so, we
342 don't want to include libc.so.1 if they are the same file, and we
343 can only check that using stat. */
345 if (bfd_stat (abfd
, &global_stat
) != 0)
346 einfo (_("%F%P: %pB: bfd_stat failed: %E\n"), abfd
);
348 /* First strip off everything before the last '/'. */
349 soname
= lbasename (bfd_get_filename (abfd
));
352 info_msg (_("found %s at %s\n"), soname
, name
);
355 lang_for_each_input_file (ldelf_stat_needed
);
356 if (global_found
!= NULL
)
358 /* Return TRUE to indicate that we found the file, even though
359 we aren't going to do anything with it. */
363 /* Specify the soname to use. */
364 bfd_elf_set_dt_needed_name (abfd
, soname
);
366 /* Tell the ELF linker that we don't want the output file to have a
367 DT_NEEDED entry for this file, unless it is used to resolve
368 references in a regular object. */
369 link_class
= DYN_DT_NEEDED
;
371 /* Tell the ELF linker that we don't want the output file to have a
372 DT_NEEDED entry for this file at all if the entry is from a file
373 with DYN_NO_ADD_NEEDED. */
374 if (needed
->by
!= NULL
375 && (bfd_elf_get_dyn_lib_class (needed
->by
) & DYN_NO_ADD_NEEDED
) != 0)
376 link_class
|= DYN_NO_NEEDED
| DYN_NO_ADD_NEEDED
;
378 bfd_elf_set_dyn_lib_class (abfd
, (enum dynamic_lib_link_class
) link_class
);
380 *link_info
.input_bfds_tail
= abfd
;
381 link_info
.input_bfds_tail
= &abfd
->link
.next
;
383 /* Add this file into the symbol table. */
384 if (! bfd_link_add_symbols (abfd
, &link_info
))
385 einfo (_("%F%P: %pB: error adding symbols: %E\n"), abfd
);
390 /* Search for a needed file in a path. */
393 ldelf_search_needed (const char *path
, struct dt_needed
*n
, int force
,
394 int is_linux
, int elfsize
)
397 const char *name
= n
->name
;
399 struct dt_needed needed
;
402 return ldelf_try_needed (n
, force
, is_linux
);
404 if (path
== NULL
|| *path
== '\0')
408 needed
.name
= n
->name
;
415 char *filename
, *sset
;
417 s
= strchr (path
, config
.rpath_separator
);
419 s
= path
+ strlen (path
);
421 #if HAVE_DOS_BASED_FILE_SYSTEM
422 /* Assume a match on the second char is part of drive specifier. */
423 else if (config
.rpath_separator
== ':'
427 s
= strchr (s
+ 1, config
.rpath_separator
);
429 s
= path
+ strlen (path
);
432 filename
= (char *) xmalloc (s
- path
+ len
+ 2);
437 memcpy (filename
, path
, s
- path
);
438 filename
[s
- path
] = '/';
439 sset
= filename
+ (s
- path
) + 1;
443 /* PR 20535: Support the same pseudo-environment variables that
444 are supported by ld.so. Namely, $ORIGIN, $LIB and $PLATFORM.
445 Since there can be more than one occurrence of these tokens in
446 the path we loop until no more are found. Since we might not
447 be able to substitute some of the tokens we maintain an offset
448 into the filename for where we should begin our scan. */
449 while ((var
= strchr (filename
+ offset
, '$')) != NULL
)
451 /* The ld.so manual page does not say, but I am going to assume that
452 these tokens are terminated by a directory separator character
453 (/) or the end of the string. There is also an implication that
454 $ORIGIN should only be used at the start of a path, but that is
457 The ld.so manual page also states that it allows ${ORIGIN},
458 ${LIB} and ${PLATFORM}, so these are supported as well.
460 FIXME: The code could be a lot cleverer about allocating space
461 for the processed string. */
462 char * end
= strchr (var
, '/');
463 const char *replacement
= NULL
;
465 char * freeme
= NULL
;
466 unsigned flen
= strlen (filename
);
469 /* Temporarily terminate the filename at the end of the token. */
477 if (strcmp (v
, "RIGIN") == 0 || strcmp (v
, "RIGIN}") == 0)
479 /* ORIGIN - replace with the full path to the directory
480 containing the program or shared object. */
481 if (needed
.by
== NULL
)
483 if (link_info
.output_bfd
== NULL
)
488 replacement
= bfd_get_filename (link_info
.output_bfd
);
491 replacement
= bfd_get_filename (needed
.by
);
497 if (replacement
[0] == '/')
498 freeme
= xstrdup (replacement
);
501 char * current_dir
= getpwd ();
503 freeme
= xmalloc (strlen (replacement
)
504 + strlen (current_dir
) + 2);
505 sprintf (freeme
, "%s/%s", current_dir
, replacement
);
508 replacement
= freeme
;
509 if ((slash
= strrchr (replacement
, '/')) != NULL
)
516 if (strcmp (v
, "IB") == 0 || strcmp (v
, "IB}") == 0)
518 /* LIB - replace with "lib" in 32-bit environments
519 and "lib64" in 64-bit environments. */
523 case 32: replacement
= "lib"; break;
524 case 64: replacement
= "lib64"; break;
532 /* Supporting $PLATFORM in a cross-hosted environment is not
533 possible. Supporting it in a native environment involves
534 loading the <sys/auxv.h> header file which loads the
535 system <elf.h> header file, which conflicts with the
536 "include/elf/mips.h" header file. */
544 char * filename2
= xmalloc (flen
+ strlen (replacement
));
548 sprintf (filename2
, "%.*s%s/%s",
549 (int)(var
- filename
), filename
,
550 replacement
, end
+ 1);
551 offset
= (var
- filename
) + 1 + strlen (replacement
);
555 sprintf (filename2
, "%.*s%s",
556 (int)(var
- filename
), filename
,
558 offset
= var
- filename
+ strlen (replacement
);
562 filename
= filename2
;
563 /* There is no need to restore the path separator (when
564 end != NULL) as we have replaced the entire string. */
569 /* We only issue an "unrecognised" message in verbose mode
570 as the $<foo> token might be a legitimate component of
571 a path name in the target's file system. */
572 info_msg (_("unrecognised or unsupported token "
573 "'%s' in search path\n"), var
);
575 /* Restore the path separator. */
578 /* PR 20784: Make sure that we resume the scan *after*
579 the token that we could not replace. */
580 offset
= (var
+ 1) - filename
;
586 needed
.name
= filename
;
588 if (ldelf_try_needed (&needed
, force
, is_linux
))
601 /* Prefix the sysroot to absolute paths in PATH, a string containing
602 paths separated by config.rpath_separator. If running on a DOS
603 file system, paths containing a drive spec won't have the sysroot
604 prefix added, unless the sysroot also specifies the same drive. */
607 ldelf_add_sysroot (const char *path
)
612 int dos_drive_sysroot
= HAS_DRIVE_SPEC (ld_sysroot
);
614 len
= strlen (ld_sysroot
);
615 for (extra
= 0, p
= path
; ; )
617 int dos_drive
= HAS_DRIVE_SPEC (p
);
621 if (IS_DIR_SEPARATOR (*p
)
623 || (dos_drive_sysroot
624 && ld_sysroot
[0] == p
[-2])))
626 if (dos_drive
&& dos_drive_sysroot
)
631 p
= strchr (p
, config
.rpath_separator
);
637 ret
= xmalloc (strlen (path
) + extra
+ 1);
639 for (q
= ret
, p
= path
; ; )
642 int dos_drive
= HAS_DRIVE_SPEC (p
);
649 if (IS_DIR_SEPARATOR (*p
)
651 || (dos_drive_sysroot
652 && ld_sysroot
[0] == p
[-2])))
654 if (dos_drive
&& dos_drive_sysroot
)
656 strcpy (q
, ld_sysroot
+ 2);
661 strcpy (q
, ld_sysroot
);
665 end
= strchr (p
, config
.rpath_separator
);
668 size_t n
= end
- p
+ 1;
683 /* Read the system search path the FreeBSD way rather than the Linux way. */
684 #ifdef HAVE_ELF_HINTS_H
685 #include <elf-hints.h>
687 #include "elf-hints-local.h"
691 ldelf_check_ld_elf_hints (const struct bfd_link_needed_list
*l
, int force
,
694 static bfd_boolean initialized
;
695 static const char *ld_elf_hints
;
696 struct dt_needed needed
;
703 tmppath
= concat (ld_sysroot
, _PATH_ELF_HINTS
, (const char *) NULL
);
704 f
= fopen (tmppath
, FOPEN_RB
);
708 struct elfhints_hdr hdr
;
710 if (fread (&hdr
, 1, sizeof (hdr
), f
) == sizeof (hdr
)
711 && hdr
.magic
== ELFHINTS_MAGIC
714 if (fseek (f
, hdr
.strtab
+ hdr
.dirlist
, SEEK_SET
) != -1)
718 b
= xmalloc (hdr
.dirlistlen
+ 1);
719 if (fread (b
, 1, hdr
.dirlistlen
+ 1, f
) ==
721 ld_elf_hints
= ldelf_add_sysroot (b
);
732 if (ld_elf_hints
== NULL
)
736 needed
.name
= l
->name
;
737 return ldelf_search_needed (ld_elf_hints
, &needed
, force
, FALSE
, elfsize
);
740 /* For a native linker, check the file /etc/ld.so.conf for directories
741 in which we may find shared libraries. /etc/ld.so.conf is really
742 only meaningful on Linux. */
744 struct ldelf_ld_so_conf
751 ldelf_parse_ld_so_conf (struct ldelf_ld_so_conf
*, const char *);
754 ldelf_parse_ld_so_conf_include (struct ldelf_ld_so_conf
*info
,
755 const char *filename
,
763 if (pattern
[0] != '/')
765 char *p
= strrchr (filename
, '/');
766 size_t patlen
= strlen (pattern
) + 1;
768 newp
= xmalloc (p
- filename
+ 1 + patlen
);
769 memcpy (newp
, filename
, p
- filename
+ 1);
770 memcpy (newp
+ (p
- filename
+ 1), pattern
, patlen
);
775 if (glob (pattern
, 0, NULL
, &gl
) == 0)
779 for (i
= 0; i
< gl
.gl_pathc
; ++i
)
780 ldelf_parse_ld_so_conf (info
, gl
.gl_pathv
[i
]);
784 /* If we do not have glob, treat the pattern as a literal filename. */
785 ldelf_parse_ld_so_conf (info
, pattern
);
792 ldelf_parse_ld_so_conf (struct ldelf_ld_so_conf
*info
, const char *filename
)
794 FILE *f
= fopen (filename
, FOPEN_RT
);
802 line
= xmalloc (linelen
);
807 /* Normally this would use getline(3), but we need to be portable. */
808 while ((q
= fgets (p
, linelen
- (p
- line
), f
)) != NULL
809 && strlen (q
) == linelen
- (p
- line
) - 1
810 && line
[linelen
- 2] != '\n')
812 line
= xrealloc (line
, 2 * linelen
);
813 p
= line
+ linelen
- 1;
817 if (q
== NULL
&& p
== line
)
820 p
= strchr (line
, '\n');
824 /* Because the file format does not know any form of quoting we
825 can search forward for the next '#' character and if found
826 make it terminating the line. */
827 p
= strchr (line
, '#');
831 /* Remove leading whitespace. NUL is no whitespace character. */
833 while (*p
== ' ' || *p
== '\f' || *p
== '\r' || *p
== '\t' || *p
== '\v')
836 /* If the line is blank it is ignored. */
840 if (CONST_STRNEQ (p
, "include") && (p
[7] == ' ' || p
[7] == '\t'))
846 while (*p
== ' ' || *p
== '\t')
854 while (*p
!= ' ' && *p
!= '\t' && *p
)
860 ldelf_parse_ld_so_conf_include (info
, filename
, dir
);
867 while (*p
&& *p
!= '=' && *p
!= ' ' && *p
!= '\t' && *p
!= '\f'
868 && *p
!= '\r' && *p
!= '\v')
871 while (p
!= dir
&& p
[-1] == '/')
873 if (info
->path
== NULL
)
875 info
->alloc
= p
- dir
+ 1 + 256;
876 info
->path
= xmalloc (info
->alloc
);
881 if (info
->len
+ 1 + (p
- dir
) >= info
->alloc
)
883 info
->alloc
+= p
- dir
+ 256;
884 info
->path
= xrealloc (info
->path
, info
->alloc
);
886 info
->path
[info
->len
++] = config
.rpath_separator
;
888 memcpy (info
->path
+ info
->len
, dir
, p
- dir
);
889 info
->len
+= p
- dir
;
890 info
->path
[info
->len
] = '\0';
900 ldelf_check_ld_so_conf (const struct bfd_link_needed_list
*l
, int force
,
901 int elfsize
, const char *prefix
)
903 static bfd_boolean initialized
;
904 static const char *ld_so_conf
;
905 struct dt_needed needed
;
910 struct ldelf_ld_so_conf info
;
913 info
.len
= info
.alloc
= 0;
914 tmppath
= concat (ld_sysroot
, prefix
, "/etc/ld.so.conf",
915 (const char *) NULL
);
916 if (!ldelf_parse_ld_so_conf (&info
, tmppath
))
919 tmppath
= concat (ld_sysroot
, "/etc/ld.so.conf",
920 (const char *) NULL
);
921 ldelf_parse_ld_so_conf (&info
, tmppath
);
927 ld_so_conf
= ldelf_add_sysroot (info
.path
);
933 if (ld_so_conf
== NULL
)
938 needed
.name
= l
->name
;
939 return ldelf_search_needed (ld_so_conf
, &needed
, force
, TRUE
, elfsize
);
942 /* See if an input file matches a DT_NEEDED entry by name. */
945 ldelf_check_needed (lang_input_statement_type
*s
)
949 /* Stop looking if we've found a loaded lib. */
950 if (global_found
!= NULL
951 && (bfd_elf_get_dyn_lib_class (global_found
->the_bfd
)
952 & DYN_AS_NEEDED
) == 0)
955 if (s
->filename
== NULL
|| s
->the_bfd
== NULL
)
958 /* Don't look for a second non-loaded as-needed lib. */
959 if (global_found
!= NULL
960 && (bfd_elf_get_dyn_lib_class (s
->the_bfd
) & DYN_AS_NEEDED
) != 0)
963 if (filename_cmp (s
->filename
, global_needed
->name
) == 0)
969 if (s
->flags
.search_dirs
)
971 const char *f
= strrchr (s
->filename
, '/');
973 && filename_cmp (f
+ 1, global_needed
->name
) == 0)
980 soname
= bfd_elf_get_dt_soname (s
->the_bfd
);
982 && filename_cmp (soname
, global_needed
->name
) == 0)
989 /* This is called after all the input files have been opened. */
992 ldelf_after_open (int use_libpath
, int native
, int is_linux
, int is_freebsd
,
993 int elfsize
, const char *prefix
)
995 struct bfd_link_needed_list
*needed
, *l
;
996 struct elf_link_hash_table
*htab
;
999 bfd
**save_input_bfd_tail
;
1001 after_open_default ();
1003 htab
= elf_hash_table (&link_info
);
1004 if (!is_elf_hash_table (htab
))
1007 if (command_line
.out_implib_filename
)
1009 unlink_if_ordinary (command_line
.out_implib_filename
);
1010 link_info
.out_implib_bfd
1011 = bfd_openw (command_line
.out_implib_filename
,
1012 bfd_get_target (link_info
.output_bfd
));
1014 if (link_info
.out_implib_bfd
== NULL
)
1016 einfo (_("%F%P: %s: can't open for writing: %E\n"),
1017 command_line
.out_implib_filename
);
1021 if (ldelf_emit_note_gnu_build_id
!= NULL
)
1023 /* Find an ELF input. */
1024 for (abfd
= link_info
.input_bfds
;
1025 abfd
!= (bfd
*) NULL
; abfd
= abfd
->link
.next
)
1026 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
1027 && bfd_count_sections (abfd
) != 0
1028 && !bfd_input_just_syms (abfd
))
1031 /* PR 10555: If there are no ELF input files do not try to
1032 create a .note.gnu-build-id section. */
1034 || !ldelf_setup_build_id (abfd
))
1036 free ((char *) ldelf_emit_note_gnu_build_id
);
1037 ldelf_emit_note_gnu_build_id
= NULL
;
1041 get_elf_backend_data (link_info
.output_bfd
)->setup_gnu_properties (&link_info
);
1043 /* Do not allow executable files to be used as inputs to the link. */
1044 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1046 if (elf_tdata (abfd
) != NULL
1047 && elf_tdata (abfd
)->elf_header
!= NULL
1048 /* FIXME: Maybe check for other non-supportable types as well ? */
1049 && elf_tdata (abfd
)->elf_header
->e_type
== ET_EXEC
)
1050 einfo (_("%F%P: cannot use executable file '%pB' as input to a link\n"),
1054 if (bfd_link_relocatable (&link_info
))
1056 if (link_info
.execstack
== !link_info
.noexecstack
)
1058 /* PR ld/16744: If "-z [no]execstack" has been specified on the
1059 command line and we are perfoming a relocatable link then no
1060 PT_GNU_STACK segment will be created and so the
1061 linkinfo.[no]execstack values set in _handle_option() will have no
1062 effect. Instead we create a .note.GNU-stack section in much the
1063 same way as the assembler does with its --[no]execstack option. */
1064 flagword flags
= SEC_READONLY
| (link_info
.execstack
? SEC_CODE
: 0);
1065 (void) bfd_make_section_with_flags (link_info
.input_bfds
,
1066 ".note.GNU-stack", flags
);
1071 if (!link_info
.traditional_format
)
1074 bfd_boolean warn_eh_frame
= FALSE
;
1077 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1081 if (bfd_link_executable (& link_info
)
1082 && elf_tdata (abfd
)->elf_header
->e_type
== ET_EXEC
)
1084 einfo (_("%F%P: cannot use executable file '%pB' as input to a link\n"),
1088 if (bfd_input_just_syms (abfd
))
1091 for (s
= abfd
->sections
; s
&& type
< COMPACT_EH_HDR
; s
= s
->next
)
1093 const char *name
= bfd_section_name (s
);
1095 if (bfd_is_abs_section (s
->output_section
))
1097 if (CONST_STRNEQ (name
, ".eh_frame_entry"))
1098 type
= COMPACT_EH_HDR
;
1099 else if (strcmp (name
, ".eh_frame") == 0 && s
->size
> 8)
1100 type
= DWARF2_EH_HDR
;
1109 else if (seen_type
!= type
)
1111 einfo (_("%F%P: compact frame descriptions incompatible with"
1112 " DWARF2 .eh_frame from %pB\n"),
1113 type
== DWARF2_EH_HDR
? abfd
: elfbfd
);
1118 && (type
== COMPACT_EH_HDR
1119 || link_info
.eh_frame_hdr_type
!= 0))
1121 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
1124 warn_eh_frame
= TRUE
;
1128 if (seen_type
== COMPACT_EH_HDR
)
1129 link_info
.eh_frame_hdr_type
= COMPACT_EH_HDR
;
1133 const struct elf_backend_data
*bed
;
1135 bed
= get_elf_backend_data (elfbfd
);
1136 s
= bfd_make_section_with_flags (elfbfd
, ".eh_frame_hdr",
1137 bed
->dynamic_sec_flags
1140 && bfd_set_section_alignment (s
, 2))
1142 htab
->eh_info
.hdr_sec
= s
;
1143 warn_eh_frame
= FALSE
;
1147 einfo (_("%P: warning: cannot create .eh_frame_hdr section,"
1148 " --eh-frame-hdr ignored\n"));
1151 /* Get the list of files which appear in DT_NEEDED entries in
1152 dynamic objects included in the link (often there will be none).
1153 For each such file, we want to track down the corresponding
1154 library, and include the symbol table in the link. This is what
1155 the runtime dynamic linker will do. Tracking the files down here
1156 permits one dynamic object to include another without requiring
1157 special action by the person doing the link. Note that the
1158 needed list can actually grow while we are stepping through this
1160 save_input_bfd_tail
= link_info
.input_bfds_tail
;
1161 needed
= bfd_elf_get_needed_list (link_info
.output_bfd
, &link_info
);
1162 for (l
= needed
; l
!= NULL
; l
= l
->next
)
1164 struct bfd_link_needed_list
*ll
;
1165 struct dt_needed n
, nn
;
1168 /* If the lib that needs this one was --as-needed and wasn't
1169 found to be needed, then this lib isn't needed either. */
1171 && (bfd_elf_get_dyn_lib_class (l
->by
) & DYN_AS_NEEDED
) != 0)
1174 /* Skip the lib if --no-copy-dt-needed-entries and
1175 --allow-shlib-undefined is in effect. */
1177 && link_info
.unresolved_syms_in_shared_libs
== RM_IGNORE
1178 && (bfd_elf_get_dyn_lib_class (l
->by
) & DYN_NO_ADD_NEEDED
) != 0)
1181 /* If we've already seen this file, skip it. */
1182 for (ll
= needed
; ll
!= l
; ll
= ll
->next
)
1184 || (bfd_elf_get_dyn_lib_class (ll
->by
) & DYN_AS_NEEDED
) == 0)
1185 && strcmp (ll
->name
, l
->name
) == 0)
1190 /* See if this file was included in the link explicitly. */
1192 global_found
= NULL
;
1193 lang_for_each_input_file (ldelf_check_needed
);
1194 if (global_found
!= NULL
1195 && (bfd_elf_get_dyn_lib_class (global_found
->the_bfd
)
1196 & DYN_AS_NEEDED
) == 0)
1203 info_msg (_("%s needed by %pB\n"), l
->name
, l
->by
);
1205 /* As-needed libs specified on the command line (or linker script)
1206 take priority over libs found in search dirs. */
1207 if (global_found
!= NULL
)
1209 nn
.name
= global_found
->filename
;
1210 if (ldelf_try_needed (&nn
, TRUE
, is_linux
))
1214 /* We need to find this file and include the symbol table. We
1215 want to search for the file in the same way that the dynamic
1216 linker will search. That means that we want to use
1217 rpath_link, rpath, then the environment variable
1218 LD_LIBRARY_PATH (native only), then the DT_RPATH/DT_RUNPATH
1219 entries (native only), then the linker script LIB_SEARCH_DIRS.
1220 We do not search using the -L arguments.
1222 We search twice. The first time, we skip objects which may
1223 introduce version mismatches. The second time, we force
1224 their use. See ldelf_vercheck comment. */
1225 for (force
= 0; force
< 2; force
++)
1228 search_dirs_type
*search
;
1230 struct bfd_link_needed_list
*rp
;
1233 if (ldelf_search_needed (command_line
.rpath_link
, &n
, force
,
1239 path
= command_line
.rpath
;
1242 path
= ldelf_add_sysroot (path
);
1243 found
= ldelf_search_needed (path
, &n
, force
,
1245 free ((char *) path
);
1252 if (command_line
.rpath_link
== NULL
1253 && command_line
.rpath
== NULL
)
1255 path
= (const char *) getenv ("LD_RUN_PATH");
1257 && ldelf_search_needed (path
, &n
, force
,
1261 path
= (const char *) getenv ("LD_LIBRARY_PATH");
1263 && ldelf_search_needed (path
, &n
, force
,
1270 rp
= bfd_elf_get_runpath_list (link_info
.output_bfd
, &link_info
);
1271 for (; !found
&& rp
!= NULL
; rp
= rp
->next
)
1273 path
= ldelf_add_sysroot (rp
->name
);
1274 found
= (rp
->by
== l
->by
1275 && ldelf_search_needed (path
, &n
, force
,
1276 is_linux
, elfsize
));
1277 free ((char *) path
);
1283 && ldelf_check_ld_elf_hints (l
, force
, elfsize
))
1287 && ldelf_check_ld_so_conf (l
, force
, elfsize
, prefix
))
1291 len
= strlen (l
->name
);
1292 for (search
= search_head
; search
!= NULL
; search
= search
->next
)
1296 if (search
->cmdline
)
1298 filename
= (char *) xmalloc (strlen (search
->name
) + len
+ 2);
1299 sprintf (filename
, "%s/%s", search
->name
, l
->name
);
1301 if (ldelf_try_needed (&nn
, force
, is_linux
))
1312 einfo (_("%P: warning: %s, needed by %pB, not found "
1313 "(try using -rpath or -rpath-link)\n"),
1317 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1318 if (bfd_get_format (abfd
) == bfd_object
1319 && ((abfd
->flags
) & DYNAMIC
) != 0
1320 && bfd_get_flavour (abfd
) == bfd_target_elf_flavour
1321 && (elf_dyn_lib_class (abfd
) & (DYN_AS_NEEDED
| DYN_NO_NEEDED
)) == 0
1322 && elf_dt_name (abfd
) != NULL
)
1324 if (bfd_elf_add_dt_needed_tag (abfd
, &link_info
) < 0)
1325 einfo (_("%F%P: failed to add DT_NEEDED dynamic tag\n"));
1328 link_info
.input_bfds_tail
= save_input_bfd_tail
;
1329 *save_input_bfd_tail
= NULL
;
1331 if (link_info
.eh_frame_hdr_type
== COMPACT_EH_HDR
)
1332 if (!bfd_elf_parse_eh_frame_entries (NULL
, &link_info
))
1333 einfo (_("%F%P: failed to parse EH frame entries\n"));
1336 static bfd_size_type
1337 id_note_section_size (bfd
*abfd ATTRIBUTE_UNUSED
)
1339 const char *style
= ldelf_emit_note_gnu_build_id
;
1341 bfd_size_type build_id_size
;
1343 size
= offsetof (Elf_External_Note
, name
[sizeof "GNU"]);
1344 size
= (size
+ 3) & -(bfd_size_type
) 4;
1346 build_id_size
= compute_build_id_size (style
);
1348 size
+= build_id_size
;
1356 write_build_id (bfd
*abfd
)
1358 const struct elf_backend_data
*bed
= get_elf_backend_data (abfd
);
1359 struct elf_obj_tdata
*t
= elf_tdata (abfd
);
1362 Elf_Internal_Shdr
*i_shdr
;
1363 unsigned char *contents
, *id_bits
;
1366 Elf_External_Note
*e_note
;
1368 style
= t
->o
->build_id
.style
;
1369 asec
= t
->o
->build_id
.sec
;
1370 if (bfd_is_abs_section (asec
->output_section
))
1372 einfo (_("%P: warning: .note.gnu.build-id section discarded,"
1373 " --build-id ignored\n"));
1376 i_shdr
= &elf_section_data (asec
->output_section
)->this_hdr
;
1378 if (i_shdr
->contents
== NULL
)
1380 if (asec
->contents
== NULL
)
1381 asec
->contents
= (unsigned char *) xmalloc (asec
->size
);
1382 contents
= asec
->contents
;
1385 contents
= i_shdr
->contents
+ asec
->output_offset
;
1387 e_note
= (Elf_External_Note
*) contents
;
1388 size
= offsetof (Elf_External_Note
, name
[sizeof "GNU"]);
1389 size
= (size
+ 3) & -(bfd_size_type
) 4;
1390 id_bits
= contents
+ size
;
1391 size
= asec
->size
- size
;
1393 bfd_h_put_32 (abfd
, sizeof "GNU", &e_note
->namesz
);
1394 bfd_h_put_32 (abfd
, size
, &e_note
->descsz
);
1395 bfd_h_put_32 (abfd
, NT_GNU_BUILD_ID
, &e_note
->type
);
1396 memcpy (e_note
->name
, "GNU", sizeof "GNU");
1398 generate_build_id (abfd
, style
, bed
->s
->checksum_contents
, id_bits
, size
);
1400 position
= i_shdr
->sh_offset
+ asec
->output_offset
;
1402 return (bfd_seek (abfd
, position
, SEEK_SET
) == 0
1403 && bfd_bwrite (contents
, size
, abfd
) == size
);
1406 /* Make .note.gnu.build-id section, and set up elf_tdata->build_id. */
1409 ldelf_setup_build_id (bfd
*ibfd
)
1415 size
= id_note_section_size (ibfd
);
1418 einfo (_("%P: warning: unrecognized --build-id style ignored\n"));
1422 flags
= (SEC_ALLOC
| SEC_LOAD
| SEC_IN_MEMORY
1423 | SEC_LINKER_CREATED
| SEC_READONLY
| SEC_DATA
);
1424 s
= bfd_make_section_with_flags (ibfd
, ".note.gnu.build-id", flags
);
1425 if (s
!= NULL
&& bfd_set_section_alignment (s
, 2))
1427 struct elf_obj_tdata
*t
= elf_tdata (link_info
.output_bfd
);
1428 t
->o
->build_id
.after_write_object_contents
= &write_build_id
;
1429 t
->o
->build_id
.style
= ldelf_emit_note_gnu_build_id
;
1430 t
->o
->build_id
.sec
= s
;
1431 elf_section_type (s
) = SHT_NOTE
;
1436 einfo (_("%P: warning: cannot create .note.gnu.build-id section,"
1437 " --build-id ignored\n"));
1441 /* Look through an expression for an assignment statement. */
1444 ldelf_find_exp_assignment (etree_type
*exp
)
1446 bfd_boolean provide
= FALSE
;
1448 switch (exp
->type
.node_class
)
1451 case etree_provided
:
1455 /* We call record_link_assignment even if the symbol is defined.
1456 This is because if it is defined by a dynamic object, we
1457 actually want to use the value defined by the linker script,
1458 not the value from the dynamic object (because we are setting
1459 symbols like etext). If the symbol is defined by a regular
1460 object, then, as it happens, calling record_link_assignment
1462 if (strcmp (exp
->assign
.dst
, ".") != 0)
1464 if (!bfd_elf_record_link_assignment (link_info
.output_bfd
,
1466 exp
->assign
.dst
, provide
,
1467 exp
->assign
.hidden
))
1468 einfo (_("%F%P: failed to record assignment to %s: %E\n"),
1471 ldelf_find_exp_assignment (exp
->assign
.src
);
1475 ldelf_find_exp_assignment (exp
->binary
.lhs
);
1476 ldelf_find_exp_assignment (exp
->binary
.rhs
);
1480 ldelf_find_exp_assignment (exp
->trinary
.cond
);
1481 ldelf_find_exp_assignment (exp
->trinary
.lhs
);
1482 ldelf_find_exp_assignment (exp
->trinary
.rhs
);
1486 ldelf_find_exp_assignment (exp
->unary
.child
);
1494 /* This is called by the before_allocation routine via
1495 lang_for_each_statement. It locates any assignment statements, and
1496 tells the ELF backend about them, in case they are assignments to
1497 symbols which are referred to by dynamic objects. */
1500 ldelf_find_statement_assignment (lang_statement_union_type
*s
)
1502 if (s
->header
.type
== lang_assignment_statement_enum
)
1503 ldelf_find_exp_assignment (s
->assignment_statement
.exp
);
1506 /* Used by before_allocation and handle_option. */
1509 ldelf_append_to_separated_string (char **to
, char *op_arg
)
1512 *to
= xstrdup (op_arg
);
1515 size_t to_len
= strlen (*to
);
1516 size_t op_arg_len
= strlen (op_arg
);
1520 /* First see whether OPTARG is already in the path. */
1523 if (strncmp (op_arg
, cp
, op_arg_len
) == 0
1524 && (cp
[op_arg_len
] == 0
1525 || cp
[op_arg_len
] == config
.rpath_separator
))
1529 /* Not yet found. */
1530 cp
= strchr (cp
, config
.rpath_separator
);
1538 buf
= xmalloc (to_len
+ op_arg_len
+ 2);
1539 sprintf (buf
, "%s%c%s", *to
,
1540 config
.rpath_separator
, op_arg
);
1547 /* This is called after the sections have been attached to output
1548 sections, but before any sizes or addresses have been set. */
1551 ldelf_before_allocation (char *audit
, char *depaudit
,
1552 const char *default_interpreter_name
)
1557 struct bfd_link_hash_entry
*ehdr_start
= NULL
;
1558 unsigned char ehdr_start_save_type
= 0;
1559 char ehdr_start_save_u
[sizeof ehdr_start
->u
1560 - sizeof ehdr_start
->u
.def
.next
] = "";
1562 if (is_elf_hash_table (link_info
.hash
))
1564 _bfd_elf_tls_setup (link_info
.output_bfd
, &link_info
);
1566 /* Make __ehdr_start hidden if it has been referenced, to
1567 prevent the symbol from being dynamic. */
1568 if (!bfd_link_relocatable (&link_info
))
1570 struct elf_link_hash_table
*htab
= elf_hash_table (&link_info
);
1571 struct elf_link_hash_entry
*h
1572 = elf_link_hash_lookup (htab
, "__ehdr_start", FALSE
, FALSE
, TRUE
);
1574 /* Only adjust the export class if the symbol was referenced
1575 and not defined, otherwise leave it alone. */
1577 && (h
->root
.type
== bfd_link_hash_new
1578 || h
->root
.type
== bfd_link_hash_undefined
1579 || h
->root
.type
== bfd_link_hash_undefweak
1580 || h
->root
.type
== bfd_link_hash_common
))
1582 const struct elf_backend_data
*bed
;
1583 bed
= get_elf_backend_data (link_info
.output_bfd
);
1584 (*bed
->elf_backend_hide_symbol
) (&link_info
, h
, TRUE
);
1585 if (ELF_ST_VISIBILITY (h
->other
) != STV_INTERNAL
)
1586 h
->other
= (h
->other
& ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN
;
1587 /* Don't leave the symbol undefined. Undefined hidden
1588 symbols typically won't have dynamic relocations, but
1589 we most likely will need dynamic relocations for
1590 __ehdr_start if we are building a PIE or shared
1592 ehdr_start
= &h
->root
;
1593 ehdr_start_save_type
= ehdr_start
->type
;
1594 memcpy (ehdr_start_save_u
,
1595 (char *) &ehdr_start
->u
+ sizeof ehdr_start
->u
.def
.next
,
1596 sizeof ehdr_start_save_u
);
1597 ehdr_start
->type
= bfd_link_hash_defined
;
1598 ehdr_start
->u
.def
.section
= bfd_abs_section_ptr
;
1599 ehdr_start
->u
.def
.value
= 0;
1603 /* If we are going to make any variable assignments, we need to
1604 let the ELF backend know about them in case the variables are
1605 referred to by dynamic objects. */
1606 lang_for_each_statement (ldelf_find_statement_assignment
);
1609 /* Let the ELF backend work out the sizes of any sections required
1610 by dynamic linking. */
1611 rpath
= command_line
.rpath
;
1613 rpath
= (const char *) getenv ("LD_RUN_PATH");
1615 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1616 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
1618 const char *audit_libs
= elf_dt_audit (abfd
);
1620 /* If the input bfd contains an audit entry, we need to add it as
1621 a dep audit entry. */
1622 if (audit_libs
&& *audit_libs
!= '\0')
1624 char *cp
= xstrdup (audit_libs
);
1628 char *cp2
= strchr (cp
, config
.rpath_separator
);
1636 if (cp
!= NULL
&& *cp
!= '\0')
1637 ldelf_append_to_separated_string (&depaudit
, cp
);
1639 cp
= more
? ++cp2
: NULL
;
1645 if (! (bfd_elf_size_dynamic_sections
1646 (link_info
.output_bfd
, command_line
.soname
, rpath
,
1647 command_line
.filter_shlib
, audit
, depaudit
,
1648 (const char * const *) command_line
.auxiliary_filters
,
1649 &link_info
, &sinterp
)))
1650 einfo (_("%F%P: failed to set dynamic section sizes: %E\n"));
1652 if (sinterp
!= NULL
)
1654 /* Let the user override the dynamic linker we are using. */
1655 if (command_line
.interpreter
!= NULL
)
1656 default_interpreter_name
= command_line
.interpreter
;
1657 if (default_interpreter_name
!= NULL
)
1659 sinterp
->contents
= (bfd_byte
*) default_interpreter_name
;
1660 sinterp
->size
= strlen ((char *) sinterp
->contents
) + 1;
1664 /* Look for any sections named .gnu.warning. As a GNU extensions,
1665 we treat such sections as containing warning messages. We print
1666 out the warning message, and then zero out the section size so
1667 that it does not get copied into the output file. */
1670 LANG_FOR_EACH_INPUT_STATEMENT (is
)
1676 if (is
->flags
.just_syms
)
1679 s
= bfd_get_section_by_name (is
->the_bfd
, ".gnu.warning");
1684 msg
= (char *) xmalloc ((size_t) (sz
+ 1));
1685 if (! bfd_get_section_contents (is
->the_bfd
, s
, msg
,
1687 einfo (_("%F%P: %pB: can't read contents of section .gnu.warning: %E\n"),
1690 (*link_info
.callbacks
->warning
) (&link_info
, msg
,
1691 (const char *) NULL
, is
->the_bfd
,
1692 (asection
*) NULL
, (bfd_vma
) 0);
1695 /* Clobber the section size, so that we don't waste space
1696 copying the warning into the output file. If we've already
1697 sized the output section, adjust its size. The adjustment
1698 is on rawsize because targets that size sections early will
1699 have called lang_reset_memory_regions after sizing. */
1700 if (s
->output_section
!= NULL
1701 && s
->output_section
->rawsize
>= s
->size
)
1702 s
->output_section
->rawsize
-= s
->size
;
1706 /* Also set SEC_EXCLUDE, so that local symbols defined in the
1707 warning section don't get copied to the output. */
1708 s
->flags
|= SEC_EXCLUDE
| SEC_KEEP
;
1712 before_allocation_default ();
1714 if (!bfd_elf_size_dynsym_hash_dynstr (link_info
.output_bfd
, &link_info
))
1715 einfo (_("%F%P: failed to set dynamic section sizes: %E\n"));
1717 if (ehdr_start
!= NULL
)
1719 /* If we twiddled __ehdr_start to defined earlier, put it back
1721 ehdr_start
->type
= ehdr_start_save_type
;
1722 memcpy ((char *) &ehdr_start
->u
+ sizeof ehdr_start
->u
.def
.next
,
1724 sizeof ehdr_start_save_u
);
1727 /* Try to open a dynamic archive. This is where we know that ELF
1728 dynamic libraries have an extension of .so (or .sl on oddball systems
1732 ldelf_open_dynamic_archive (const char *arch
, search_dirs_type
*search
,
1733 lang_input_statement_type
*entry
)
1735 const char *filename
;
1738 bfd_boolean opened
= FALSE
;
1740 if (! entry
->flags
.maybe_archive
)
1743 filename
= entry
->filename
;
1744 len
= strlen (search
->name
) + strlen (filename
);
1745 if (entry
->flags
.full_name_provided
)
1748 string
= (char *) xmalloc (len
);
1749 sprintf (string
, "%s/%s", search
->name
, filename
);
1755 len
+= strlen (arch
) + sizeof "/lib.so";
1756 #ifdef EXTRA_SHLIB_EXTENSION
1757 xlen
= (strlen (EXTRA_SHLIB_EXTENSION
) > 3
1758 ? strlen (EXTRA_SHLIB_EXTENSION
) - 3
1761 string
= (char *) xmalloc (len
+ xlen
);
1762 sprintf (string
, "%s/lib%s%s.so", search
->name
, filename
, arch
);
1763 #ifdef EXTRA_SHLIB_EXTENSION
1764 /* Try the .so extension first. If that fails build a new filename
1765 using EXTRA_SHLIB_EXTENSION. */
1766 opened
= ldfile_try_open_bfd (string
, entry
);
1768 strcpy (string
+ len
- 4, EXTRA_SHLIB_EXTENSION
);
1772 if (!opened
&& !ldfile_try_open_bfd (string
, entry
))
1778 entry
->filename
= string
;
1780 /* We have found a dynamic object to include in the link. The ELF
1781 backend linker will create a DT_NEEDED entry in the .dynamic
1782 section naming this file. If this file includes a DT_SONAME
1783 entry, it will be used. Otherwise, the ELF linker will just use
1784 the name of the file. For an archive found by searching, like
1785 this one, the DT_NEEDED entry should consist of just the name of
1786 the file, without the path information used to find it. Note
1787 that we only need to do this if we have a dynamic object; an
1788 archive will never be referenced by a DT_NEEDED entry.
1790 FIXME: This approach--using bfd_elf_set_dt_needed_name--is not
1791 very pretty. I haven't been able to think of anything that is
1793 if (bfd_check_format (entry
->the_bfd
, bfd_object
)
1794 && (entry
->the_bfd
->flags
& DYNAMIC
) != 0)
1796 ASSERT (entry
->flags
.maybe_archive
&& entry
->flags
.search_dirs
);
1798 /* Rather than duplicating the logic above. Just use the
1799 filename we recorded earlier. */
1801 if (!entry
->flags
.full_name_provided
)
1802 filename
= lbasename (entry
->filename
);
1803 bfd_elf_set_dt_needed_name (entry
->the_bfd
, filename
);
1809 /* A variant of lang_output_section_find used by place_orphan. */
1811 static lang_output_section_statement_type
*
1812 output_rel_find (int isdyn
, int rela
)
1814 lang_output_section_statement_type
*lookup
;
1815 lang_output_section_statement_type
*last
= NULL
;
1816 lang_output_section_statement_type
*last_alloc
= NULL
;
1817 lang_output_section_statement_type
*last_ro_alloc
= NULL
;
1818 lang_output_section_statement_type
*last_rel
= NULL
;
1819 lang_output_section_statement_type
*last_rel_alloc
= NULL
;
1821 for (lookup
= (void *) lang_os_list
.head
;
1823 lookup
= lookup
->next
)
1825 if (lookup
->constraint
>= 0
1826 && CONST_STRNEQ (lookup
->name
, ".rel"))
1828 int lookrela
= lookup
->name
[4] == 'a';
1830 /* .rel.dyn must come before all other reloc sections, to suit
1835 /* Don't place after .rel.plt as doing so results in wrong
1837 if (strcmp (".plt", lookup
->name
+ 4 + lookrela
) == 0)
1840 if (rela
== lookrela
|| last_rel
== NULL
)
1842 if ((rela
== lookrela
|| last_rel_alloc
== NULL
)
1843 && lookup
->bfd_section
!= NULL
1844 && (lookup
->bfd_section
->flags
& SEC_ALLOC
) != 0)
1845 last_rel_alloc
= lookup
;
1849 if (lookup
->bfd_section
!= NULL
1850 && (lookup
->bfd_section
->flags
& SEC_ALLOC
) != 0)
1852 last_alloc
= lookup
;
1853 if ((lookup
->bfd_section
->flags
& SEC_READONLY
) != 0)
1854 last_ro_alloc
= lookup
;
1859 return last_rel_alloc
;
1865 return last_ro_alloc
;
1873 /* Return whether IN is suitable to be part of OUT. */
1876 elf_orphan_compatible (asection
*in
, asection
*out
)
1878 /* Non-zero sh_info implies a section with SHF_INFO_LINK with
1879 unknown semantics for the generic linker, or a SHT_REL/SHT_RELA
1880 section where sh_info specifies a symbol table. (We won't see
1881 SHT_GROUP, SHT_SYMTAB or SHT_DYNSYM sections here.) We clearly
1882 can't merge SHT_REL/SHT_RELA using differing symbol tables, and
1883 shouldn't merge sections with differing unknown semantics. */
1884 if (elf_section_data (out
)->this_hdr
.sh_info
1885 != elf_section_data (in
)->this_hdr
.sh_info
)
1887 /* We can't merge with a member of an output section group or merge
1888 two sections with differing SHF_EXCLUDE or other processor and OS
1889 specific flags when doing a relocatable link. */
1890 if (bfd_link_relocatable (&link_info
)
1891 && (elf_next_in_group (out
) != NULL
1892 || ((elf_section_flags (out
) ^ elf_section_flags (in
))
1893 & (SHF_MASKPROC
| SHF_MASKOS
)) != 0))
1895 return _bfd_elf_match_sections_by_type (link_info
.output_bfd
, out
,
1899 /* Place an orphan section. We use this to put random SHF_ALLOC
1900 sections in the right segment. */
1902 lang_output_section_statement_type
*
1903 ldelf_place_orphan (asection
*s
, const char *secname
, int constraint
)
1905 static struct orphan_save hold
[] =
1908 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_CODE
,
1911 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1914 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
| SEC_THREAD_LOCAL
,
1917 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
,
1923 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1926 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1929 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
| SEC_SMALL_DATA
,
1935 enum orphan_save_index
1947 static int orphan_init_done
= 0;
1948 struct orphan_save
*place
;
1949 lang_output_section_statement_type
*after
;
1950 lang_output_section_statement_type
*os
;
1951 lang_output_section_statement_type
*match_by_name
= NULL
;
1953 int elfinput
= s
->owner
->xvec
->flavour
== bfd_target_elf_flavour
;
1954 int elfoutput
= link_info
.output_bfd
->xvec
->flavour
== bfd_target_elf_flavour
;
1955 unsigned int sh_type
= elfinput
? elf_section_type (s
) : SHT_NULL
;
1959 if (!bfd_link_relocatable (&link_info
)
1960 && link_info
.combreloc
1961 && (s
->flags
& SEC_ALLOC
))
1967 secname
= ".rela.dyn";
1971 secname
= ".rel.dyn";
1977 else if (CONST_STRNEQ (secname
, ".rel"))
1979 secname
= secname
[4] == 'a' ? ".rela.dyn" : ".rel.dyn";
1984 if (!bfd_link_relocatable (&link_info
)
1987 && (s
->flags
& SEC_ALLOC
) != 0
1988 && (elf_tdata (s
->owner
)->has_gnu_osabi
& elf_gnu_osabi_mbind
) != 0
1989 && (elf_section_flags (s
) & SHF_GNU_MBIND
) != 0)
1991 /* Find the output mbind section with the same type, attributes
1992 and sh_info field. */
1993 for (os
= (void *) lang_os_list
.head
;
1996 if (os
->bfd_section
!= NULL
1997 && !bfd_is_abs_section (os
->bfd_section
)
1998 && (elf_section_flags (os
->bfd_section
) & SHF_GNU_MBIND
) != 0
1999 && ((s
->flags
& (SEC_ALLOC
2004 == (os
->bfd_section
->flags
& (SEC_ALLOC
2009 && (elf_section_data (os
->bfd_section
)->this_hdr
.sh_info
2010 == elf_section_data (s
)->this_hdr
.sh_info
))
2012 lang_add_section (&os
->children
, s
, NULL
, os
);
2016 /* Create the output mbind section with the ".mbind." prefix
2018 if ((s
->flags
& (SEC_LOAD
| SEC_HAS_CONTENTS
)) == 0)
2019 secname
= ".mbind.bss";
2020 else if ((s
->flags
& SEC_READONLY
) == 0)
2021 secname
= ".mbind.data";
2022 else if ((s
->flags
& SEC_CODE
) == 0)
2023 secname
= ".mbind.rodata";
2025 secname
= ".mbind.text";
2026 elf_tdata (link_info
.output_bfd
)->has_gnu_osabi
|= elf_gnu_osabi_mbind
;
2029 /* Look through the script to see where to place this section. The
2030 script includes entries added by previous lang_insert_orphan
2031 calls, so this loop puts multiple compatible orphans of the same
2032 name into a single output section. */
2033 if (constraint
== 0)
2034 for (os
= lang_output_section_find (secname
);
2036 os
= next_matching_output_section_statement (os
, 0))
2038 /* If we don't match an existing output section, tell
2039 lang_insert_orphan to create a new output section. */
2040 constraint
= SPECIAL
;
2042 /* Check to see if we already have an output section statement
2043 with this name, and its bfd section has compatible flags.
2044 If the section already exists but does not have any flags
2045 set, then it has been created by the linker, possibly as a
2046 result of a --section-start command line switch. */
2047 if (os
->bfd_section
!= NULL
2048 && (os
->bfd_section
->flags
== 0
2049 || (((s
->flags
^ os
->bfd_section
->flags
)
2050 & (SEC_LOAD
| SEC_ALLOC
)) == 0
2053 || elf_orphan_compatible (s
, os
->bfd_section
)))))
2055 lang_add_section (&os
->children
, s
, NULL
, os
);
2059 /* Save unused output sections in case we can match them
2060 against orphans later. */
2061 if (os
->bfd_section
== NULL
)
2065 /* If we didn't match an active output section, see if we matched an
2066 unused one and use that. */
2069 lang_add_section (&match_by_name
->children
, s
, NULL
, match_by_name
);
2070 return match_by_name
;
2073 if (!orphan_init_done
)
2075 struct orphan_save
*ho
;
2077 for (ho
= hold
; ho
< hold
+ sizeof (hold
) / sizeof (hold
[0]); ++ho
)
2078 if (ho
->name
!= NULL
)
2080 ho
->os
= lang_output_section_find (ho
->name
);
2081 if (ho
->os
!= NULL
&& ho
->os
->flags
== 0)
2082 ho
->os
->flags
= ho
->flags
;
2084 orphan_init_done
= 1;
2087 /* If this is a final link, then always put .gnu.warning.SYMBOL
2088 sections into the .text section to get them out of the way. */
2089 if (bfd_link_executable (&link_info
)
2090 && CONST_STRNEQ (s
->name
, ".gnu.warning.")
2091 && hold
[orphan_text
].os
!= NULL
)
2093 os
= hold
[orphan_text
].os
;
2094 lang_add_section (&os
->children
, s
, NULL
, os
);
2099 if (!bfd_link_relocatable (&link_info
))
2102 while ((nexts
= bfd_get_next_section_by_name (nexts
->owner
, nexts
))
2104 if (nexts
->output_section
== NULL
2105 && (nexts
->flags
& SEC_EXCLUDE
) == 0
2106 && ((nexts
->flags
^ flags
) & (SEC_LOAD
| SEC_ALLOC
)) == 0
2107 && (nexts
->owner
->flags
& DYNAMIC
) == 0
2108 && !bfd_input_just_syms (nexts
->owner
)
2109 && _bfd_elf_match_sections_by_type (nexts
->owner
, nexts
,
2111 flags
= (((flags
^ SEC_READONLY
)
2112 | (nexts
->flags
^ SEC_READONLY
))
2116 /* Decide which segment the section should go in based on the
2117 section name and section flags. We put loadable .note sections
2118 right after the .interp section, so that the PT_NOTE segment is
2119 stored right after the program headers where the OS can read it
2120 in the first page. */
2123 if ((flags
& (SEC_ALLOC
| SEC_DEBUGGING
)) == 0)
2124 place
= &hold
[orphan_nonalloc
];
2125 else if ((flags
& SEC_ALLOC
) == 0)
2127 else if ((flags
& SEC_LOAD
) != 0
2129 ? sh_type
== SHT_NOTE
2130 : CONST_STRNEQ (secname
, ".note")))
2131 place
= &hold
[orphan_interp
];
2132 else if ((flags
& (SEC_LOAD
| SEC_HAS_CONTENTS
| SEC_THREAD_LOCAL
)) == 0)
2133 place
= &hold
[orphan_bss
];
2134 else if ((flags
& SEC_SMALL_DATA
) != 0)
2135 place
= &hold
[orphan_sdata
];
2136 else if ((flags
& SEC_THREAD_LOCAL
) != 0)
2137 place
= &hold
[orphan_tdata
];
2138 else if ((flags
& SEC_READONLY
) == 0)
2139 place
= &hold
[orphan_data
];
2140 else if ((flags
& SEC_LOAD
) != 0
2142 ? sh_type
== SHT_RELA
|| sh_type
== SHT_REL
2143 : CONST_STRNEQ (secname
, ".rel")))
2144 place
= &hold
[orphan_rel
];
2145 else if ((flags
& SEC_CODE
) == 0)
2146 place
= &hold
[orphan_rodata
];
2148 place
= &hold
[orphan_text
];
2153 if (place
->os
== NULL
)
2155 if (place
->name
!= NULL
)
2156 place
->os
= lang_output_section_find (place
->name
);
2159 int rela
= elfinput
? sh_type
== SHT_RELA
: secname
[4] == 'a';
2160 place
->os
= output_rel_find (isdyn
, rela
);
2166 = lang_output_section_find_by_flags (s
, flags
, &place
->os
,
2167 _bfd_elf_match_sections_by_type
);
2169 /* *ABS* is always the first output section statement. */
2170 after
= (void *) lang_os_list
.head
;
2173 return lang_insert_orphan (s
, secname
, constraint
, after
, place
, NULL
, NULL
);
2177 ldelf_before_place_orphans (void)
2181 for (abfd
= link_info
.input_bfds
;
2182 abfd
!= (bfd
*) NULL
; abfd
= abfd
->link
.next
)
2183 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
2184 && bfd_count_sections (abfd
) != 0
2185 && !bfd_input_just_syms (abfd
))
2188 for (isec
= abfd
->sections
; isec
!= NULL
; isec
= isec
->next
)
2190 /* Discard a section if any of its linked-to section has
2192 asection
*linked_to_sec
;
2193 for (linked_to_sec
= elf_linked_to_section (isec
);
2194 linked_to_sec
!= NULL
;
2195 linked_to_sec
= elf_linked_to_section (linked_to_sec
))
2196 if (discarded_section (linked_to_sec
))
2198 isec
->output_section
= bfd_abs_section_ptr
;