1 /* ELF emulation code for targets using elf.em.
2 Copyright (C) 1991-2021 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 bool 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 (startswith (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 bool 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 (startswith (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 bool 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
->root
))
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 /* Discard input .note.gnu.build-id sections. */
1047 s
= bfd_get_section_by_name (abfd
, ".note.gnu.build-id");
1050 if (s
!= elf_tdata (link_info
.output_bfd
)->o
->build_id
.sec
)
1051 s
->flags
|= SEC_EXCLUDE
;
1052 s
= bfd_get_next_section_by_name (NULL
, s
);
1055 if (abfd
->xvec
->flavour
== bfd_target_elf_flavour
1056 && !bfd_input_just_syms (abfd
)
1057 && elf_tdata (abfd
) != NULL
1058 /* FIXME: Maybe check for other non-supportable types as well ? */
1059 && (elf_tdata (abfd
)->elf_header
->e_type
== ET_EXEC
1060 || (elf_tdata (abfd
)->elf_header
->e_type
== ET_DYN
1061 && elf_tdata (abfd
)->is_pie
)))
1062 einfo (_("%F%P: cannot use executable file '%pB' as input to a link\n"),
1066 if (bfd_link_relocatable (&link_info
))
1068 if (link_info
.execstack
== !link_info
.noexecstack
)
1070 /* PR ld/16744: If "-z [no]execstack" has been specified on the
1071 command line and we are perfoming a relocatable link then no
1072 PT_GNU_STACK segment will be created and so the
1073 linkinfo.[no]execstack values set in _handle_option() will have no
1074 effect. Instead we create a .note.GNU-stack section in much the
1075 same way as the assembler does with its --[no]execstack option. */
1076 flagword flags
= SEC_READONLY
| (link_info
.execstack
? SEC_CODE
: 0);
1077 (void) bfd_make_section_with_flags (link_info
.input_bfds
,
1078 ".note.GNU-stack", flags
);
1083 if (!link_info
.traditional_format
)
1086 bool warn_eh_frame
= false;
1089 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1093 if (bfd_input_just_syms (abfd
))
1096 for (s
= abfd
->sections
; s
&& type
< COMPACT_EH_HDR
; s
= s
->next
)
1098 const char *name
= bfd_section_name (s
);
1100 if (bfd_is_abs_section (s
->output_section
))
1102 if (startswith (name
, ".eh_frame_entry"))
1103 type
= COMPACT_EH_HDR
;
1104 else if (strcmp (name
, ".eh_frame") == 0 && s
->size
> 8)
1105 type
= DWARF2_EH_HDR
;
1114 else if (seen_type
!= type
)
1116 einfo (_("%F%P: compact frame descriptions incompatible with"
1117 " DWARF2 .eh_frame from %pB\n"),
1118 type
== DWARF2_EH_HDR
? abfd
: elfbfd
);
1123 && (type
== COMPACT_EH_HDR
1124 || link_info
.eh_frame_hdr_type
!= 0))
1126 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
1129 warn_eh_frame
= true;
1133 if (seen_type
== COMPACT_EH_HDR
)
1134 link_info
.eh_frame_hdr_type
= COMPACT_EH_HDR
;
1138 const struct elf_backend_data
*bed
;
1140 bed
= get_elf_backend_data (elfbfd
);
1141 s
= bfd_make_section_with_flags (elfbfd
, ".eh_frame_hdr",
1142 bed
->dynamic_sec_flags
1145 && bfd_set_section_alignment (s
, 2))
1147 htab
->eh_info
.hdr_sec
= s
;
1148 warn_eh_frame
= false;
1152 einfo (_("%P: warning: cannot create .eh_frame_hdr section,"
1153 " --eh-frame-hdr ignored\n"));
1156 /* Get the list of files which appear in DT_NEEDED entries in
1157 dynamic objects included in the link (often there will be none).
1158 For each such file, we want to track down the corresponding
1159 library, and include the symbol table in the link. This is what
1160 the runtime dynamic linker will do. Tracking the files down here
1161 permits one dynamic object to include another without requiring
1162 special action by the person doing the link. Note that the
1163 needed list can actually grow while we are stepping through this
1165 save_input_bfd_tail
= link_info
.input_bfds_tail
;
1166 needed
= bfd_elf_get_needed_list (link_info
.output_bfd
, &link_info
);
1167 for (l
= needed
; l
!= NULL
; l
= l
->next
)
1169 struct bfd_link_needed_list
*ll
;
1170 struct dt_needed n
, nn
;
1173 /* If the lib that needs this one was --as-needed and wasn't
1174 found to be needed, then this lib isn't needed either. */
1176 && (bfd_elf_get_dyn_lib_class (l
->by
) & DYN_AS_NEEDED
) != 0)
1179 /* Skip the lib if --no-copy-dt-needed-entries and
1180 --allow-shlib-undefined is in effect. */
1182 && link_info
.unresolved_syms_in_shared_libs
== RM_IGNORE
1183 && (bfd_elf_get_dyn_lib_class (l
->by
) & DYN_NO_ADD_NEEDED
) != 0)
1186 /* If we've already seen this file, skip it. */
1187 for (ll
= needed
; ll
!= l
; ll
= ll
->next
)
1189 || (bfd_elf_get_dyn_lib_class (ll
->by
) & DYN_AS_NEEDED
) == 0)
1190 && strcmp (ll
->name
, l
->name
) == 0)
1195 /* See if this file was included in the link explicitly. */
1197 global_found
= NULL
;
1198 lang_for_each_input_file (ldelf_check_needed
);
1199 if (global_found
!= NULL
1200 && (bfd_elf_get_dyn_lib_class (global_found
->the_bfd
)
1201 & DYN_AS_NEEDED
) == 0)
1208 info_msg (_("%s needed by %pB\n"), l
->name
, l
->by
);
1210 /* As-needed libs specified on the command line (or linker script)
1211 take priority over libs found in search dirs. */
1212 if (global_found
!= NULL
)
1214 nn
.name
= global_found
->filename
;
1215 if (ldelf_try_needed (&nn
, true, is_linux
))
1219 /* We need to find this file and include the symbol table. We
1220 want to search for the file in the same way that the dynamic
1221 linker will search. That means that we want to use
1222 rpath_link, rpath, then the environment variable
1223 LD_LIBRARY_PATH (native only), then the DT_RPATH/DT_RUNPATH
1224 entries (native only), then the linker script LIB_SEARCH_DIRS.
1225 We do not search using the -L arguments.
1227 We search twice. The first time, we skip objects which may
1228 introduce version mismatches. The second time, we force
1229 their use. See ldelf_vercheck comment. */
1230 for (force
= 0; force
< 2; force
++)
1233 search_dirs_type
*search
;
1235 struct bfd_link_needed_list
*rp
;
1238 if (ldelf_search_needed (command_line
.rpath_link
, &n
, force
,
1244 path
= command_line
.rpath
;
1247 path
= ldelf_add_sysroot (path
);
1248 found
= ldelf_search_needed (path
, &n
, force
,
1250 free ((char *) path
);
1257 if (command_line
.rpath_link
== NULL
1258 && command_line
.rpath
== NULL
)
1260 path
= (const char *) getenv ("LD_RUN_PATH");
1262 && ldelf_search_needed (path
, &n
, force
,
1266 path
= (const char *) getenv ("LD_LIBRARY_PATH");
1268 && ldelf_search_needed (path
, &n
, force
,
1275 rp
= bfd_elf_get_runpath_list (link_info
.output_bfd
, &link_info
);
1276 for (; !found
&& rp
!= NULL
; rp
= rp
->next
)
1278 path
= ldelf_add_sysroot (rp
->name
);
1279 found
= (rp
->by
== l
->by
1280 && ldelf_search_needed (path
, &n
, force
,
1281 is_linux
, elfsize
));
1282 free ((char *) path
);
1288 && ldelf_check_ld_elf_hints (l
, force
, elfsize
))
1292 && ldelf_check_ld_so_conf (l
, force
, elfsize
, prefix
))
1296 len
= strlen (l
->name
);
1297 for (search
= search_head
; search
!= NULL
; search
= search
->next
)
1301 if (search
->cmdline
)
1303 filename
= (char *) xmalloc (strlen (search
->name
) + len
+ 2);
1304 sprintf (filename
, "%s/%s", search
->name
, l
->name
);
1306 if (ldelf_try_needed (&nn
, force
, is_linux
))
1317 einfo (_("%P: warning: %s, needed by %pB, not found "
1318 "(try using -rpath or -rpath-link)\n"),
1322 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1323 if (bfd_get_format (abfd
) == bfd_object
1324 && ((abfd
->flags
) & DYNAMIC
) != 0
1325 && bfd_get_flavour (abfd
) == bfd_target_elf_flavour
1326 && (elf_dyn_lib_class (abfd
) & (DYN_AS_NEEDED
| DYN_NO_NEEDED
)) == 0
1327 && elf_dt_name (abfd
) != NULL
)
1329 if (bfd_elf_add_dt_needed_tag (abfd
, &link_info
) < 0)
1330 einfo (_("%F%P: failed to add DT_NEEDED dynamic tag\n"));
1333 link_info
.input_bfds_tail
= save_input_bfd_tail
;
1334 *save_input_bfd_tail
= NULL
;
1336 if (link_info
.eh_frame_hdr_type
== COMPACT_EH_HDR
)
1337 if (!bfd_elf_parse_eh_frame_entries (NULL
, &link_info
))
1338 einfo (_("%F%P: failed to parse EH frame entries\n"));
1341 static bfd_size_type
1342 id_note_section_size (bfd
*abfd ATTRIBUTE_UNUSED
)
1344 const char *style
= ldelf_emit_note_gnu_build_id
;
1346 bfd_size_type build_id_size
;
1348 size
= offsetof (Elf_External_Note
, name
[sizeof "GNU"]);
1349 size
= (size
+ 3) & -(bfd_size_type
) 4;
1351 build_id_size
= compute_build_id_size (style
);
1353 size
+= build_id_size
;
1361 write_build_id (bfd
*abfd
)
1363 const struct elf_backend_data
*bed
= get_elf_backend_data (abfd
);
1364 struct elf_obj_tdata
*t
= elf_tdata (abfd
);
1367 Elf_Internal_Shdr
*i_shdr
;
1368 unsigned char *contents
, *id_bits
;
1371 Elf_External_Note
*e_note
;
1373 style
= t
->o
->build_id
.style
;
1374 asec
= t
->o
->build_id
.sec
;
1375 if (bfd_is_abs_section (asec
->output_section
))
1377 einfo (_("%P: warning: .note.gnu.build-id section discarded,"
1378 " --build-id ignored\n"));
1381 i_shdr
= &elf_section_data (asec
->output_section
)->this_hdr
;
1383 if (i_shdr
->contents
== NULL
)
1385 if (asec
->contents
== NULL
)
1386 asec
->contents
= (unsigned char *) xmalloc (asec
->size
);
1387 contents
= asec
->contents
;
1390 contents
= i_shdr
->contents
+ asec
->output_offset
;
1392 e_note
= (Elf_External_Note
*) contents
;
1393 size
= offsetof (Elf_External_Note
, name
[sizeof "GNU"]);
1394 size
= (size
+ 3) & -(bfd_size_type
) 4;
1395 id_bits
= contents
+ size
;
1396 size
= asec
->size
- size
;
1398 /* Clear the build ID field. */
1399 memset (id_bits
, 0, size
);
1401 bfd_h_put_32 (abfd
, sizeof "GNU", &e_note
->namesz
);
1402 bfd_h_put_32 (abfd
, size
, &e_note
->descsz
);
1403 bfd_h_put_32 (abfd
, NT_GNU_BUILD_ID
, &e_note
->type
);
1404 memcpy (e_note
->name
, "GNU", sizeof "GNU");
1406 generate_build_id (abfd
, style
, bed
->s
->checksum_contents
, id_bits
, size
);
1408 position
= i_shdr
->sh_offset
+ asec
->output_offset
;
1410 return (bfd_seek (abfd
, position
, SEEK_SET
) == 0
1411 && bfd_bwrite (contents
, size
, abfd
) == size
);
1414 /* Make .note.gnu.build-id section, and set up elf_tdata->build_id. */
1417 ldelf_setup_build_id (bfd
*ibfd
)
1423 size
= id_note_section_size (ibfd
);
1426 einfo (_("%P: warning: unrecognized --build-id style ignored\n"));
1430 flags
= (SEC_ALLOC
| SEC_LOAD
| SEC_IN_MEMORY
1431 | SEC_LINKER_CREATED
| SEC_READONLY
| SEC_DATA
);
1432 s
= bfd_make_section_anyway_with_flags (ibfd
, ".note.gnu.build-id",
1434 if (s
!= NULL
&& bfd_set_section_alignment (s
, 2))
1436 struct elf_obj_tdata
*t
= elf_tdata (link_info
.output_bfd
);
1437 t
->o
->build_id
.after_write_object_contents
= &write_build_id
;
1438 t
->o
->build_id
.style
= ldelf_emit_note_gnu_build_id
;
1439 t
->o
->build_id
.sec
= s
;
1440 elf_section_type (s
) = SHT_NOTE
;
1445 einfo (_("%P: warning: cannot create .note.gnu.build-id section,"
1446 " --build-id ignored\n"));
1450 /* Look through an expression for an assignment statement. */
1453 ldelf_find_exp_assignment (etree_type
*exp
)
1455 bool provide
= false;
1457 switch (exp
->type
.node_class
)
1460 case etree_provided
:
1464 /* We call record_link_assignment even if the symbol is defined.
1465 This is because if it is defined by a dynamic object, we
1466 actually want to use the value defined by the linker script,
1467 not the value from the dynamic object (because we are setting
1468 symbols like etext). If the symbol is defined by a regular
1469 object, then, as it happens, calling record_link_assignment
1471 if (strcmp (exp
->assign
.dst
, ".") != 0)
1473 if (!bfd_elf_record_link_assignment (link_info
.output_bfd
,
1475 exp
->assign
.dst
, provide
,
1476 exp
->assign
.hidden
))
1477 einfo (_("%F%P: failed to record assignment to %s: %E\n"),
1480 ldelf_find_exp_assignment (exp
->assign
.src
);
1484 ldelf_find_exp_assignment (exp
->binary
.lhs
);
1485 ldelf_find_exp_assignment (exp
->binary
.rhs
);
1489 ldelf_find_exp_assignment (exp
->trinary
.cond
);
1490 ldelf_find_exp_assignment (exp
->trinary
.lhs
);
1491 ldelf_find_exp_assignment (exp
->trinary
.rhs
);
1495 ldelf_find_exp_assignment (exp
->unary
.child
);
1503 /* This is called by the before_allocation routine via
1504 lang_for_each_statement. It locates any assignment statements, and
1505 tells the ELF backend about them, in case they are assignments to
1506 symbols which are referred to by dynamic objects. */
1509 ldelf_find_statement_assignment (lang_statement_union_type
*s
)
1511 if (s
->header
.type
== lang_assignment_statement_enum
)
1512 ldelf_find_exp_assignment (s
->assignment_statement
.exp
);
1515 /* Used by before_allocation and handle_option. */
1518 ldelf_append_to_separated_string (char **to
, char *op_arg
)
1521 *to
= xstrdup (op_arg
);
1524 size_t to_len
= strlen (*to
);
1525 size_t op_arg_len
= strlen (op_arg
);
1529 /* First see whether OPTARG is already in the path. */
1532 if (strncmp (op_arg
, cp
, op_arg_len
) == 0
1533 && (cp
[op_arg_len
] == 0
1534 || cp
[op_arg_len
] == config
.rpath_separator
))
1538 /* Not yet found. */
1539 cp
= strchr (cp
, config
.rpath_separator
);
1547 buf
= xmalloc (to_len
+ op_arg_len
+ 2);
1548 sprintf (buf
, "%s%c%s", *to
,
1549 config
.rpath_separator
, op_arg
);
1556 /* This is called after the sections have been attached to output
1557 sections, but before any sizes or addresses have been set. */
1560 ldelf_before_allocation (char *audit
, char *depaudit
,
1561 const char *default_interpreter_name
)
1566 struct bfd_link_hash_entry
*ehdr_start
= NULL
;
1567 unsigned char ehdr_start_save_type
= 0;
1568 char ehdr_start_save_u
[sizeof ehdr_start
->u
1569 - sizeof ehdr_start
->u
.def
.next
] = "";
1571 if (is_elf_hash_table (link_info
.hash
))
1573 _bfd_elf_tls_setup (link_info
.output_bfd
, &link_info
);
1575 /* Make __ehdr_start hidden if it has been referenced, to
1576 prevent the symbol from being dynamic. */
1577 if (!bfd_link_relocatable (&link_info
))
1579 struct elf_link_hash_table
*htab
= elf_hash_table (&link_info
);
1580 struct elf_link_hash_entry
*h
1581 = elf_link_hash_lookup (htab
, "__ehdr_start", false, false, true);
1583 /* Only adjust the export class if the symbol was referenced
1584 and not defined, otherwise leave it alone. */
1586 && (h
->root
.type
== bfd_link_hash_new
1587 || h
->root
.type
== bfd_link_hash_undefined
1588 || h
->root
.type
== bfd_link_hash_undefweak
1589 || h
->root
.type
== bfd_link_hash_common
))
1591 const struct elf_backend_data
*bed
;
1592 bed
= get_elf_backend_data (link_info
.output_bfd
);
1593 (*bed
->elf_backend_hide_symbol
) (&link_info
, h
, true);
1594 if (ELF_ST_VISIBILITY (h
->other
) != STV_INTERNAL
)
1595 h
->other
= (h
->other
& ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN
;
1596 /* Don't leave the symbol undefined. Undefined hidden
1597 symbols typically won't have dynamic relocations, but
1598 we most likely will need dynamic relocations for
1599 __ehdr_start if we are building a PIE or shared
1601 ehdr_start
= &h
->root
;
1602 ehdr_start_save_type
= ehdr_start
->type
;
1603 memcpy (ehdr_start_save_u
,
1604 (char *) &ehdr_start
->u
+ sizeof ehdr_start
->u
.def
.next
,
1605 sizeof ehdr_start_save_u
);
1606 ehdr_start
->type
= bfd_link_hash_defined
;
1607 /* It will be converted to section-relative later. */
1608 ehdr_start
->rel_from_abs
= 1;
1609 ehdr_start
->u
.def
.section
= bfd_abs_section_ptr
;
1610 ehdr_start
->u
.def
.value
= 0;
1614 /* If we are going to make any variable assignments, we need to
1615 let the ELF backend know about them in case the variables are
1616 referred to by dynamic objects. */
1617 lang_for_each_statement (ldelf_find_statement_assignment
);
1620 /* Let the ELF backend work out the sizes of any sections required
1621 by dynamic linking. */
1622 rpath
= command_line
.rpath
;
1624 rpath
= (const char *) getenv ("LD_RUN_PATH");
1626 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1627 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
1629 const char *audit_libs
= elf_dt_audit (abfd
);
1631 /* If the input bfd contains an audit entry, we need to add it as
1632 a dep audit entry. */
1633 if (audit_libs
&& *audit_libs
!= '\0')
1635 char *cp
= xstrdup (audit_libs
);
1639 char *cp2
= strchr (cp
, config
.rpath_separator
);
1647 if (cp
!= NULL
&& *cp
!= '\0')
1648 ldelf_append_to_separated_string (&depaudit
, cp
);
1650 cp
= more
? ++cp2
: NULL
;
1656 if (! (bfd_elf_size_dynamic_sections
1657 (link_info
.output_bfd
, command_line
.soname
, rpath
,
1658 command_line
.filter_shlib
, audit
, depaudit
,
1659 (const char * const *) command_line
.auxiliary_filters
,
1660 &link_info
, &sinterp
)))
1661 einfo (_("%F%P: failed to set dynamic section sizes: %E\n"));
1663 if (sinterp
!= NULL
)
1665 /* Let the user override the dynamic linker we are using. */
1666 if (command_line
.interpreter
!= NULL
)
1667 default_interpreter_name
= command_line
.interpreter
;
1668 if (default_interpreter_name
!= NULL
)
1670 sinterp
->contents
= (bfd_byte
*) default_interpreter_name
;
1671 sinterp
->size
= strlen ((char *) sinterp
->contents
) + 1;
1675 /* Look for any sections named .gnu.warning. As a GNU extensions,
1676 we treat such sections as containing warning messages. We print
1677 out the warning message, and then zero out the section size so
1678 that it does not get copied into the output file. */
1681 LANG_FOR_EACH_INPUT_STATEMENT (is
)
1687 if (is
->flags
.just_syms
)
1690 s
= bfd_get_section_by_name (is
->the_bfd
, ".gnu.warning");
1695 msg
= (char *) xmalloc ((size_t) (sz
+ 1));
1696 if (! bfd_get_section_contents (is
->the_bfd
, s
, msg
,
1698 einfo (_("%F%P: %pB: can't read contents of section .gnu.warning: %E\n"),
1701 (*link_info
.callbacks
->warning
) (&link_info
, msg
,
1702 (const char *) NULL
, is
->the_bfd
,
1703 (asection
*) NULL
, (bfd_vma
) 0);
1706 /* Clobber the section size, so that we don't waste space
1707 copying the warning into the output file. If we've already
1708 sized the output section, adjust its size. The adjustment
1709 is on rawsize because targets that size sections early will
1710 have called lang_reset_memory_regions after sizing. */
1711 if (s
->output_section
!= NULL
1712 && s
->output_section
->rawsize
>= s
->size
)
1713 s
->output_section
->rawsize
-= s
->size
;
1717 /* Also set SEC_EXCLUDE, so that local symbols defined in the
1718 warning section don't get copied to the output. */
1719 s
->flags
|= SEC_EXCLUDE
| SEC_KEEP
;
1723 before_allocation_default ();
1725 if (!bfd_elf_size_dynsym_hash_dynstr (link_info
.output_bfd
, &link_info
))
1726 einfo (_("%F%P: failed to set dynamic section sizes: %E\n"));
1728 if (ehdr_start
!= NULL
)
1730 /* If we twiddled __ehdr_start to defined earlier, put it back
1732 ehdr_start
->type
= ehdr_start_save_type
;
1733 memcpy ((char *) &ehdr_start
->u
+ sizeof ehdr_start
->u
.def
.next
,
1735 sizeof ehdr_start_save_u
);
1738 /* Try to open a dynamic archive. This is where we know that ELF
1739 dynamic libraries have an extension of .so (or .sl on oddball systems
1743 ldelf_open_dynamic_archive (const char *arch
, search_dirs_type
*search
,
1744 lang_input_statement_type
*entry
)
1746 const char *filename
;
1749 bool opened
= false;
1751 if (! entry
->flags
.maybe_archive
)
1754 filename
= entry
->filename
;
1755 len
= strlen (search
->name
) + strlen (filename
);
1756 if (entry
->flags
.full_name_provided
)
1759 string
= (char *) xmalloc (len
);
1760 sprintf (string
, "%s/%s", search
->name
, filename
);
1766 len
+= strlen (arch
) + sizeof "/lib.so";
1767 #ifdef EXTRA_SHLIB_EXTENSION
1768 xlen
= (strlen (EXTRA_SHLIB_EXTENSION
) > 3
1769 ? strlen (EXTRA_SHLIB_EXTENSION
) - 3
1772 string
= (char *) xmalloc (len
+ xlen
);
1773 sprintf (string
, "%s/lib%s%s.so", search
->name
, filename
, arch
);
1774 #ifdef EXTRA_SHLIB_EXTENSION
1775 /* Try the .so extension first. If that fails build a new filename
1776 using EXTRA_SHLIB_EXTENSION. */
1777 opened
= ldfile_try_open_bfd (string
, entry
);
1779 strcpy (string
+ len
- 4, EXTRA_SHLIB_EXTENSION
);
1783 if (!opened
&& !ldfile_try_open_bfd (string
, entry
))
1789 entry
->filename
= string
;
1791 /* We have found a dynamic object to include in the link. The ELF
1792 backend linker will create a DT_NEEDED entry in the .dynamic
1793 section naming this file. If this file includes a DT_SONAME
1794 entry, it will be used. Otherwise, the ELF linker will just use
1795 the name of the file. For an archive found by searching, like
1796 this one, the DT_NEEDED entry should consist of just the name of
1797 the file, without the path information used to find it. Note
1798 that we only need to do this if we have a dynamic object; an
1799 archive will never be referenced by a DT_NEEDED entry.
1801 FIXME: This approach--using bfd_elf_set_dt_needed_name--is not
1802 very pretty. I haven't been able to think of anything that is
1804 if (bfd_check_format (entry
->the_bfd
, bfd_object
)
1805 && (entry
->the_bfd
->flags
& DYNAMIC
) != 0)
1807 ASSERT (entry
->flags
.maybe_archive
&& entry
->flags
.search_dirs
);
1809 /* Rather than duplicating the logic above. Just use the
1810 filename we recorded earlier. */
1812 if (!entry
->flags
.full_name_provided
)
1813 filename
= lbasename (entry
->filename
);
1814 bfd_elf_set_dt_needed_name (entry
->the_bfd
, filename
);
1820 /* A variant of lang_output_section_find used by place_orphan. */
1822 static lang_output_section_statement_type
*
1823 output_rel_find (int isdyn
, int rela
)
1825 lang_output_section_statement_type
*lookup
;
1826 lang_output_section_statement_type
*last
= NULL
;
1827 lang_output_section_statement_type
*last_alloc
= NULL
;
1828 lang_output_section_statement_type
*last_ro_alloc
= NULL
;
1829 lang_output_section_statement_type
*last_rel
= NULL
;
1830 lang_output_section_statement_type
*last_rel_alloc
= NULL
;
1832 for (lookup
= (void *) lang_os_list
.head
;
1834 lookup
= lookup
->next
)
1836 if (lookup
->constraint
>= 0
1837 && startswith (lookup
->name
, ".rel"))
1839 int lookrela
= lookup
->name
[4] == 'a';
1841 /* .rel.dyn must come before all other reloc sections, to suit
1846 /* Don't place after .rel.plt as doing so results in wrong
1848 if (strcmp (".plt", lookup
->name
+ 4 + lookrela
) == 0)
1851 if (rela
== lookrela
|| last_rel
== NULL
)
1853 if ((rela
== lookrela
|| last_rel_alloc
== NULL
)
1854 && lookup
->bfd_section
!= NULL
1855 && (lookup
->bfd_section
->flags
& SEC_ALLOC
) != 0)
1856 last_rel_alloc
= lookup
;
1860 if (lookup
->bfd_section
!= NULL
1861 && (lookup
->bfd_section
->flags
& SEC_ALLOC
) != 0)
1863 last_alloc
= lookup
;
1864 if ((lookup
->bfd_section
->flags
& SEC_READONLY
) != 0)
1865 last_ro_alloc
= lookup
;
1870 return last_rel_alloc
;
1876 return last_ro_alloc
;
1884 /* Return whether IN is suitable to be part of OUT. */
1887 elf_orphan_compatible (asection
*in
, asection
*out
)
1889 /* Non-zero sh_info implies a section with SHF_INFO_LINK with
1890 unknown semantics for the generic linker, or a SHT_REL/SHT_RELA
1891 section where sh_info specifies a symbol table. (We won't see
1892 SHT_GROUP, SHT_SYMTAB or SHT_DYNSYM sections here.) We clearly
1893 can't merge SHT_REL/SHT_RELA using differing symbol tables, and
1894 shouldn't merge sections with differing unknown semantics. */
1895 if (elf_section_data (out
)->this_hdr
.sh_info
1896 != elf_section_data (in
)->this_hdr
.sh_info
)
1898 /* We can't merge with a member of an output section group or merge
1899 two sections with differing SHF_EXCLUDE or other processor and OS
1900 specific flags when doing a relocatable link. */
1901 if (bfd_link_relocatable (&link_info
)
1902 && (elf_next_in_group (out
) != NULL
1903 || ((elf_section_flags (out
) ^ elf_section_flags (in
))
1904 & (SHF_MASKPROC
| SHF_MASKOS
)) != 0))
1906 return _bfd_elf_match_sections_by_type (link_info
.output_bfd
, out
,
1910 /* Place an orphan section. We use this to put random SHF_ALLOC
1911 sections in the right segment. */
1913 lang_output_section_statement_type
*
1914 ldelf_place_orphan (asection
*s
, const char *secname
, int constraint
)
1916 static struct orphan_save hold
[] =
1919 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_CODE
,
1922 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1925 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
| SEC_THREAD_LOCAL
,
1928 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
,
1934 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1937 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1940 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
| SEC_SMALL_DATA
,
1946 enum orphan_save_index
1958 static int orphan_init_done
= 0;
1959 struct orphan_save
*place
;
1960 lang_output_section_statement_type
*after
;
1961 lang_output_section_statement_type
*os
;
1962 lang_output_section_statement_type
*match_by_name
= NULL
;
1964 int elfinput
= s
->owner
->xvec
->flavour
== bfd_target_elf_flavour
;
1965 int elfoutput
= link_info
.output_bfd
->xvec
->flavour
== bfd_target_elf_flavour
;
1966 unsigned int sh_type
= elfinput
? elf_section_type (s
) : SHT_NULL
;
1970 if (!bfd_link_relocatable (&link_info
)
1971 && link_info
.combreloc
1972 && (s
->flags
& SEC_ALLOC
))
1978 secname
= ".rela.dyn";
1982 secname
= ".rel.dyn";
1988 else if (startswith (secname
, ".rel"))
1990 secname
= secname
[4] == 'a' ? ".rela.dyn" : ".rel.dyn";
1995 if (!bfd_link_relocatable (&link_info
)
1998 && (s
->flags
& SEC_ALLOC
) != 0
1999 && (elf_tdata (s
->owner
)->has_gnu_osabi
& elf_gnu_osabi_mbind
) != 0
2000 && (elf_section_flags (s
) & SHF_GNU_MBIND
) != 0)
2002 /* Find the output mbind section with the same type, attributes
2003 and sh_info field. */
2004 for (os
= (void *) lang_os_list
.head
;
2007 if (os
->bfd_section
!= NULL
2008 && !bfd_is_abs_section (os
->bfd_section
)
2009 && (elf_section_flags (os
->bfd_section
) & SHF_GNU_MBIND
) != 0
2010 && ((s
->flags
& (SEC_ALLOC
2015 == (os
->bfd_section
->flags
& (SEC_ALLOC
2020 && (elf_section_data (os
->bfd_section
)->this_hdr
.sh_info
2021 == elf_section_data (s
)->this_hdr
.sh_info
))
2023 lang_add_section (&os
->children
, s
, NULL
, NULL
, os
);
2027 /* Create the output mbind section with the ".mbind." prefix
2029 if ((s
->flags
& (SEC_LOAD
| SEC_HAS_CONTENTS
)) == 0)
2030 secname
= ".mbind.bss";
2031 else if ((s
->flags
& SEC_READONLY
) == 0)
2032 secname
= ".mbind.data";
2033 else if ((s
->flags
& SEC_CODE
) == 0)
2034 secname
= ".mbind.rodata";
2036 secname
= ".mbind.text";
2037 elf_tdata (link_info
.output_bfd
)->has_gnu_osabi
|= elf_gnu_osabi_mbind
;
2040 /* Look through the script to see where to place this section. The
2041 script includes entries added by previous lang_insert_orphan
2042 calls, so this loop puts multiple compatible orphans of the same
2043 name into a single output section. */
2044 if (constraint
== 0)
2045 for (os
= lang_output_section_find (secname
);
2047 os
= next_matching_output_section_statement (os
, 0))
2049 /* If we don't match an existing output section, tell
2050 lang_insert_orphan to create a new output section. */
2051 constraint
= SPECIAL
;
2053 /* Check to see if we already have an output section statement
2054 with this name, and its bfd section has compatible flags.
2055 If the section already exists but does not have any flags
2056 set, then it has been created by the linker, possibly as a
2057 result of a --section-start command line switch. */
2058 if (os
->bfd_section
!= NULL
2059 && (os
->bfd_section
->flags
== 0
2060 || (((s
->flags
^ os
->bfd_section
->flags
)
2061 & (SEC_LOAD
| SEC_ALLOC
)) == 0
2064 || elf_orphan_compatible (s
, os
->bfd_section
)))))
2066 lang_add_section (&os
->children
, s
, NULL
, NULL
, os
);
2070 /* Save unused output sections in case we can match them
2071 against orphans later. */
2072 if (os
->bfd_section
== NULL
)
2076 /* If we didn't match an active output section, see if we matched an
2077 unused one and use that. */
2080 lang_add_section (&match_by_name
->children
, s
, NULL
, NULL
, match_by_name
);
2081 return match_by_name
;
2084 if (!orphan_init_done
)
2086 struct orphan_save
*ho
;
2088 for (ho
= hold
; ho
< hold
+ sizeof (hold
) / sizeof (hold
[0]); ++ho
)
2089 if (ho
->name
!= NULL
)
2091 ho
->os
= lang_output_section_find (ho
->name
);
2092 if (ho
->os
!= NULL
&& ho
->os
->flags
== 0)
2093 ho
->os
->flags
= ho
->flags
;
2095 orphan_init_done
= 1;
2098 /* If this is a final link, then always put .gnu.warning.SYMBOL
2099 sections into the .text section to get them out of the way. */
2100 if (bfd_link_executable (&link_info
)
2101 && startswith (s
->name
, ".gnu.warning.")
2102 && hold
[orphan_text
].os
!= NULL
)
2104 os
= hold
[orphan_text
].os
;
2105 lang_add_section (&os
->children
, s
, NULL
, NULL
, os
);
2110 if (!bfd_link_relocatable (&link_info
))
2113 while ((nexts
= bfd_get_next_section_by_name (nexts
->owner
, nexts
))
2115 if (nexts
->output_section
== NULL
2116 && (nexts
->flags
& SEC_EXCLUDE
) == 0
2117 && ((nexts
->flags
^ flags
) & (SEC_LOAD
| SEC_ALLOC
)) == 0
2118 && (nexts
->owner
->flags
& DYNAMIC
) == 0
2119 && !bfd_input_just_syms (nexts
->owner
)
2120 && _bfd_elf_match_sections_by_type (nexts
->owner
, nexts
,
2122 flags
= (((flags
^ SEC_READONLY
)
2123 | (nexts
->flags
^ SEC_READONLY
))
2127 /* Decide which segment the section should go in based on the
2128 section name and section flags. We put loadable .note sections
2129 right after the .interp section, so that the PT_NOTE segment is
2130 stored right after the program headers where the OS can read it
2131 in the first page. */
2134 if ((flags
& (SEC_ALLOC
| SEC_DEBUGGING
)) == 0)
2135 place
= &hold
[orphan_nonalloc
];
2136 else if ((flags
& SEC_ALLOC
) == 0)
2138 else if ((flags
& SEC_LOAD
) != 0
2140 ? sh_type
== SHT_NOTE
2141 : startswith (secname
, ".note")))
2142 place
= &hold
[orphan_interp
];
2143 else if ((flags
& (SEC_LOAD
| SEC_HAS_CONTENTS
| SEC_THREAD_LOCAL
)) == 0)
2144 place
= &hold
[orphan_bss
];
2145 else if ((flags
& SEC_SMALL_DATA
) != 0)
2146 place
= &hold
[orphan_sdata
];
2147 else if ((flags
& SEC_THREAD_LOCAL
) != 0)
2148 place
= &hold
[orphan_tdata
];
2149 else if ((flags
& SEC_READONLY
) == 0)
2150 place
= &hold
[orphan_data
];
2151 else if ((flags
& SEC_LOAD
) != 0
2153 ? sh_type
== SHT_RELA
|| sh_type
== SHT_REL
2154 : startswith (secname
, ".rel")))
2155 place
= &hold
[orphan_rel
];
2156 else if ((flags
& SEC_CODE
) == 0)
2157 place
= &hold
[orphan_rodata
];
2159 place
= &hold
[orphan_text
];
2164 if (place
->os
== NULL
)
2166 if (place
->name
!= NULL
)
2167 place
->os
= lang_output_section_find (place
->name
);
2170 int rela
= elfinput
? sh_type
== SHT_RELA
: secname
[4] == 'a';
2171 place
->os
= output_rel_find (isdyn
, rela
);
2177 = lang_output_section_find_by_flags (s
, flags
, &place
->os
,
2178 _bfd_elf_match_sections_by_type
);
2180 /* *ABS* is always the first output section statement. */
2181 after
= (void *) lang_os_list
.head
;
2184 return lang_insert_orphan (s
, secname
, constraint
, after
, place
, NULL
, NULL
);
2188 ldelf_before_place_orphans (void)
2192 for (abfd
= link_info
.input_bfds
;
2193 abfd
!= (bfd
*) NULL
; abfd
= abfd
->link
.next
)
2194 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
2195 && bfd_count_sections (abfd
) != 0
2196 && !bfd_input_just_syms (abfd
))
2199 for (isec
= abfd
->sections
; isec
!= NULL
; isec
= isec
->next
)
2201 /* Discard a section if any of its linked-to section has
2203 asection
*linked_to_sec
;
2204 for (linked_to_sec
= elf_linked_to_section (isec
);
2205 linked_to_sec
!= NULL
&& !linked_to_sec
->linker_mark
;
2206 linked_to_sec
= elf_linked_to_section (linked_to_sec
))
2208 if (discarded_section (linked_to_sec
))
2210 isec
->output_section
= bfd_abs_section_ptr
;
2211 isec
->flags
|= SEC_EXCLUDE
;
2214 linked_to_sec
->linker_mark
= 1;
2216 for (linked_to_sec
= elf_linked_to_section (isec
);
2217 linked_to_sec
!= NULL
&& linked_to_sec
->linker_mark
;
2218 linked_to_sec
= elf_linked_to_section (linked_to_sec
))
2219 linked_to_sec
->linker_mark
= 0;
2225 ldelf_set_output_arch (void)
2227 set_output_arch_default ();
2228 if (link_info
.output_bfd
->xvec
->flavour
== bfd_target_elf_flavour
)
2229 elf_link_info (link_info
.output_bfd
) = &link_info
;