1 /* ELF emulation code for targets using elf.em.
2 Copyright (C) 1991-2019 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"
33 #include "ldbuildid.h"
47 /* Style of .note.gnu.build-id section. */
48 const char *ldelf_emit_note_gnu_build_id
;
50 /* These variables are required to pass information back and forth
51 between after_open and check_needed and stat_needed and vercheck. */
53 static struct bfd_link_needed_list
*global_needed
;
54 static lang_input_statement_type
*global_found
;
55 static struct stat global_stat
;
56 static struct bfd_link_needed_list
*global_vercheck_needed
;
57 static bfd_boolean global_vercheck_failed
;
60 ldelf_after_parse (void)
62 if (bfd_link_pie (&link_info
))
63 link_info
.flags_1
|= (bfd_vma
) DF_1_PIE
;
65 if (bfd_link_executable (&link_info
)
66 && link_info
.nointerp
)
68 if (link_info
.dynamic_undefined_weak
> 0)
69 einfo (_("%P: warning: -z dynamic-undefined-weak ignored\n"));
70 link_info
.dynamic_undefined_weak
= 0;
72 after_parse_default ();
75 /* Handle the generation of DT_NEEDED tags. */
78 ldelf_load_symbols (lang_input_statement_type
*entry
)
82 /* Tell the ELF linker that we don't want the output file to have a
83 DT_NEEDED entry for this file, unless it is used to resolve
84 references in a regular object. */
85 if (entry
->flags
.add_DT_NEEDED_for_regular
)
86 link_class
= DYN_AS_NEEDED
;
88 /* Tell the ELF linker that we don't want the output file to have a
89 DT_NEEDED entry for any dynamic library in DT_NEEDED tags from
91 if (!entry
->flags
.add_DT_NEEDED_for_dynamic
)
92 link_class
|= DYN_NO_ADD_NEEDED
;
94 if (entry
->flags
.just_syms
95 && (bfd_get_file_flags (entry
->the_bfd
) & DYNAMIC
) != 0)
96 einfo (_("%F%P: %pB: --just-symbols may not be used on DSO\n"),
100 || (bfd_get_file_flags (entry
->the_bfd
) & DYNAMIC
) == 0)
103 bfd_elf_set_dyn_lib_class (entry
->the_bfd
,
104 (enum dynamic_lib_link_class
) link_class
);
106 /* Continue on with normal load_symbols processing. */
110 /* On Linux, it's possible to have different versions of the same
111 shared library linked against different versions of libc. The
112 dynamic linker somehow tags which libc version to use in
113 /etc/ld.so.cache, and, based on the libc that it sees in the
114 executable, chooses which version of the shared library to use.
116 We try to do a similar check here by checking whether this shared
117 library needs any other shared libraries which may conflict with
118 libraries we have already included in the link. If it does, we
119 skip it, and try to find another shared library farther on down the
122 This is called via lang_for_each_input_file.
123 GLOBAL_VERCHECK_NEEDED is the list of objects needed by the object
124 which we are checking. This sets GLOBAL_VERCHECK_FAILED if we find
125 a conflicting version. */
128 ldelf_vercheck (lang_input_statement_type
*s
)
131 struct bfd_link_needed_list
*l
;
133 if (global_vercheck_failed
)
135 if (s
->the_bfd
== NULL
136 || (bfd_get_file_flags (s
->the_bfd
) & DYNAMIC
) == 0)
139 soname
= bfd_elf_get_dt_soname (s
->the_bfd
);
141 soname
= lbasename (bfd_get_filename (s
->the_bfd
));
143 for (l
= global_vercheck_needed
; l
!= NULL
; l
= l
->next
)
147 if (filename_cmp (soname
, l
->name
) == 0)
149 /* Probably can't happen, but it's an easy check. */
153 if (strchr (l
->name
, '/') != NULL
)
156 suffix
= strstr (l
->name
, ".so.");
160 suffix
+= sizeof ".so." - 1;
162 if (filename_ncmp (soname
, l
->name
, suffix
- l
->name
) == 0)
164 /* Here we know that S is a dynamic object FOO.SO.VER1, and
165 the object we are considering needs a dynamic object
166 FOO.SO.VER2, and VER1 and VER2 are different. This
167 appears to be a version mismatch, so we tell the caller
168 to try a different version of this library. */
169 global_vercheck_failed
= TRUE
;
176 /* See if an input file matches a DT_NEEDED entry by running stat on
180 ldelf_stat_needed (lang_input_statement_type
*s
)
186 if (global_found
!= NULL
)
188 if (s
->the_bfd
== NULL
)
191 /* If this input file was an as-needed entry, and wasn't found to be
192 needed at the stage it was linked, then don't say we have loaded it. */
193 if ((bfd_elf_get_dyn_lib_class (s
->the_bfd
) & DYN_AS_NEEDED
) != 0)
196 if (bfd_stat (s
->the_bfd
, &st
) != 0)
198 einfo (_("%P: %pB: bfd_stat failed: %E\n"), s
->the_bfd
);
202 /* Some operating systems, e.g. Windows, do not provide a meaningful
203 st_ino; they always set it to zero. (Windows does provide a
204 meaningful st_dev.) Do not indicate a duplicate library in that
205 case. While there is no guarantee that a system that provides
206 meaningful inode numbers will never set st_ino to zero, this is
207 merely an optimization, so we do not need to worry about false
209 if (st
.st_dev
== global_stat
.st_dev
210 && st
.st_ino
== global_stat
.st_ino
217 /* We issue a warning if it looks like we are including two
218 different versions of the same shared library. For example,
219 there may be a problem if -lc picks up libc.so.6 but some other
220 shared library has a DT_NEEDED entry of libc.so.5. This is a
221 heuristic test, and it will only work if the name looks like
222 NAME.so.VERSION. FIXME: Depending on file names is error-prone.
223 If we really want to issue warnings about mixing version numbers
224 of shared libraries, we need to find a better way. */
226 if (strchr (global_needed
->name
, '/') != NULL
)
228 suffix
= strstr (global_needed
->name
, ".so.");
231 suffix
+= sizeof ".so." - 1;
233 soname
= bfd_elf_get_dt_soname (s
->the_bfd
);
235 soname
= lbasename (s
->filename
);
237 if (filename_ncmp (soname
, global_needed
->name
,
238 suffix
- global_needed
->name
) == 0)
239 einfo (_("%P: warning: %s, needed by %pB, may conflict with %s\n"),
240 global_needed
->name
, global_needed
->by
, soname
);
243 /* This function is called for each possible name for a dynamic object
244 named by a DT_NEEDED entry. The FORCE parameter indicates whether
245 to skip the check for a conflicting version. */
248 ldelf_try_needed (struct dt_needed
*needed
, int force
, int is_linux
)
251 const char *name
= needed
->name
;
255 abfd
= bfd_openr (name
, bfd_get_target (link_info
.output_bfd
));
259 info_msg (_("attempt to open %s failed\n"), name
);
263 /* Linker needs to decompress sections. */
264 abfd
->flags
|= BFD_DECOMPRESS
;
266 if (! bfd_check_format (abfd
, bfd_object
))
271 if ((bfd_get_file_flags (abfd
) & DYNAMIC
) == 0)
277 /* For DT_NEEDED, they have to match. */
278 if (abfd
->xvec
!= link_info
.output_bfd
->xvec
)
284 /* Check whether this object would include any conflicting library
285 versions. If FORCE is set, then we skip this check; we use this
286 the second time around, if we couldn't find any compatible
287 instance of the shared library. */
291 struct bfd_link_needed_list
*needs
;
293 if (! bfd_elf_get_bfd_needed_list (abfd
, &needs
))
294 einfo (_("%F%P: %pB: bfd_elf_get_bfd_needed_list failed: %E\n"), abfd
);
298 global_vercheck_needed
= needs
;
299 global_vercheck_failed
= FALSE
;
300 lang_for_each_input_file (ldelf_vercheck
);
301 if (global_vercheck_failed
)
304 /* Return FALSE to force the caller to move on to try
305 another file on the search path. */
309 /* But wait! It gets much worse. On Linux, if a shared
310 library does not use libc at all, we are supposed to skip
311 it the first time around in case we encounter a shared
312 library later on with the same name which does use the
313 version of libc that we want. This is much too horrible
314 to use on any system other than Linux. */
317 struct bfd_link_needed_list
*l
;
319 for (l
= needs
; l
!= NULL
; l
= l
->next
)
320 if (CONST_STRNEQ (l
->name
, "libc.so"))
331 /* We've found a dynamic object matching the DT_NEEDED entry. */
333 /* We have already checked that there is no other input file of the
334 same name. We must now check again that we are not including the
335 same file twice. We need to do this because on many systems
336 libc.so is a symlink to, e.g., libc.so.1. The SONAME entry will
337 reference libc.so.1. If we have already included libc.so, we
338 don't want to include libc.so.1 if they are the same file, and we
339 can only check that using stat. */
341 if (bfd_stat (abfd
, &global_stat
) != 0)
342 einfo (_("%F%P: %pB: bfd_stat failed: %E\n"), abfd
);
344 /* First strip off everything before the last '/'. */
345 soname
= lbasename (bfd_get_filename (abfd
));
348 info_msg (_("found %s at %s\n"), soname
, name
);
351 lang_for_each_input_file (ldelf_stat_needed
);
352 if (global_found
!= NULL
)
354 /* Return TRUE to indicate that we found the file, even though
355 we aren't going to do anything with it. */
359 /* Specify the soname to use. */
360 bfd_elf_set_dt_needed_name (abfd
, soname
);
362 /* Tell the ELF linker that we don't want the output file to have a
363 DT_NEEDED entry for this file, unless it is used to resolve
364 references in a regular object. */
365 link_class
= DYN_DT_NEEDED
;
367 /* Tell the ELF linker that we don't want the output file to have a
368 DT_NEEDED entry for this file at all if the entry is from a file
369 with DYN_NO_ADD_NEEDED. */
370 if (needed
->by
!= NULL
371 && (bfd_elf_get_dyn_lib_class (needed
->by
) & DYN_NO_ADD_NEEDED
) != 0)
372 link_class
|= DYN_NO_NEEDED
| DYN_NO_ADD_NEEDED
;
374 bfd_elf_set_dyn_lib_class (abfd
, (enum dynamic_lib_link_class
) link_class
);
376 /* Add this file into the symbol table. */
377 if (! bfd_link_add_symbols (abfd
, &link_info
))
378 einfo (_("%F%P: %pB: error adding symbols: %E\n"), abfd
);
383 /* Search for a needed file in a path. */
386 ldelf_search_needed (const char *path
, struct dt_needed
*n
, int force
,
387 int is_linux
, int elfsize
)
390 const char *name
= n
->name
;
392 struct dt_needed needed
;
395 return ldelf_try_needed (n
, force
, is_linux
);
397 if (path
== NULL
|| *path
== '\0')
401 needed
.name
= n
->name
;
408 char *filename
, *sset
;
410 s
= strchr (path
, config
.rpath_separator
);
412 s
= path
+ strlen (path
);
414 #if HAVE_DOS_BASED_FILE_SYSTEM
415 /* Assume a match on the second char is part of drive specifier. */
416 else if (config
.rpath_separator
== ':'
420 s
= strchr (s
+ 1, config
.rpath_separator
);
422 s
= path
+ strlen (path
);
425 filename
= (char *) xmalloc (s
- path
+ len
+ 2);
430 memcpy (filename
, path
, s
- path
);
431 filename
[s
- path
] = '/';
432 sset
= filename
+ (s
- path
) + 1;
436 /* PR 20535: Support the same pseudo-environment variables that
437 are supported by ld.so. Namely, $ORIGIN, $LIB and $PLATFORM.
438 Since there can be more than one occurrence of these tokens in
439 the path we loop until no more are found. Since we might not
440 be able to substitute some of the tokens we maintain an offset
441 into the filename for where we should begin our scan. */
442 while ((var
= strchr (filename
+ offset
, '$')) != NULL
)
444 /* The ld.so manual page does not say, but I am going to assume that
445 these tokens are terminated by a directory separator character
446 (/) or the end of the string. There is also an implication that
447 $ORIGIN should only be used at the start of a path, but that is
450 The ld.so manual page also states that it allows ${ORIGIN},
451 ${LIB} and ${PLATFORM}, so these are supported as well.
453 FIXME: The code could be a lot cleverer about allocating space
454 for the processed string. */
455 char * end
= strchr (var
, '/');
456 const char *replacement
= NULL
;
458 char * freeme
= NULL
;
459 unsigned flen
= strlen (filename
);
462 /* Temporarily terminate the filename at the end of the token. */
470 if (strcmp (v
, "RIGIN") == 0 || strcmp (v
, "RIGIN}") == 0)
472 /* ORIGIN - replace with the full path to the directory
473 containing the program or shared object. */
474 if (needed
.by
== NULL
)
476 if (link_info
.output_bfd
== NULL
)
481 replacement
= bfd_get_filename (link_info
.output_bfd
);
484 replacement
= bfd_get_filename (needed
.by
);
490 if (replacement
[0] == '/')
491 freeme
= xstrdup (replacement
);
494 char * current_dir
= getpwd ();
496 freeme
= xmalloc (strlen (replacement
)
497 + strlen (current_dir
) + 2);
498 sprintf (freeme
, "%s/%s", current_dir
, replacement
);
501 replacement
= freeme
;
502 if ((slash
= strrchr (replacement
, '/')) != NULL
)
509 if (strcmp (v
, "IB") == 0 || strcmp (v
, "IB}") == 0)
511 /* LIB - replace with "lib" in 32-bit environments
512 and "lib64" in 64-bit environments. */
516 case 32: replacement
= "lib"; break;
517 case 64: replacement
= "lib64"; break;
525 /* Supporting $PLATFORM in a cross-hosted environment is not
526 possible. Supporting it in a native environment involves
527 loading the <sys/auxv.h> header file which loads the
528 system <elf.h> header file, which conflicts with the
529 "include/elf/mips.h" header file. */
537 char * filename2
= xmalloc (flen
+ strlen (replacement
));
541 sprintf (filename2
, "%.*s%s/%s",
542 (int)(var
- filename
), filename
,
543 replacement
, end
+ 1);
544 offset
= (var
- filename
) + 1 + strlen (replacement
);
548 sprintf (filename2
, "%.*s%s",
549 (int)(var
- filename
), filename
,
551 offset
= var
- filename
+ strlen (replacement
);
555 filename
= filename2
;
556 /* There is no need to restore the path separator (when
557 end != NULL) as we have replaced the entire string. */
562 /* We only issue an "unrecognised" message in verbose mode
563 as the $<foo> token might be a legitimate component of
564 a path name in the target's file system. */
565 info_msg (_("unrecognised or unsupported token "
566 "'%s' in search path\n"), var
);
568 /* Restore the path separator. */
571 /* PR 20784: Make sure that we resume the scan *after*
572 the token that we could not replace. */
573 offset
= (var
+ 1) - filename
;
579 needed
.name
= filename
;
581 if (ldelf_try_needed (&needed
, force
, is_linux
))
594 /* Prefix the sysroot to absolute paths in PATH, a string containing
595 paths separated by config.rpath_separator. If running on a DOS
596 file system, paths containing a drive spec won't have the sysroot
597 prefix added, unless the sysroot also specifies the same drive. */
600 ldelf_add_sysroot (const char *path
)
605 int dos_drive_sysroot
= HAS_DRIVE_SPEC (ld_sysroot
);
607 len
= strlen (ld_sysroot
);
608 for (extra
= 0, p
= path
; ; )
610 int dos_drive
= HAS_DRIVE_SPEC (p
);
614 if (IS_DIR_SEPARATOR (*p
)
616 || (dos_drive_sysroot
617 && ld_sysroot
[0] == p
[-2])))
619 if (dos_drive
&& dos_drive_sysroot
)
624 p
= strchr (p
, config
.rpath_separator
);
630 ret
= xmalloc (strlen (path
) + extra
+ 1);
632 for (q
= ret
, p
= path
; ; )
635 int dos_drive
= HAS_DRIVE_SPEC (p
);
642 if (IS_DIR_SEPARATOR (*p
)
644 || (dos_drive_sysroot
645 && ld_sysroot
[0] == p
[-2])))
647 if (dos_drive
&& dos_drive_sysroot
)
649 strcpy (q
, ld_sysroot
+ 2);
654 strcpy (q
, ld_sysroot
);
658 end
= strchr (p
, config
.rpath_separator
);
661 size_t n
= end
- p
+ 1;
676 /* Read the system search path the FreeBSD way rather than the Linux way. */
677 #ifdef HAVE_ELF_HINTS_H
678 #include <elf-hints.h>
680 #include "elf-hints-local.h"
684 ldelf_check_ld_elf_hints (const struct bfd_link_needed_list
*l
, int force
,
687 static bfd_boolean initialized
;
688 static const char *ld_elf_hints
;
689 struct dt_needed needed
;
696 tmppath
= concat (ld_sysroot
, _PATH_ELF_HINTS
, (const char *) NULL
);
697 f
= fopen (tmppath
, FOPEN_RB
);
701 struct elfhints_hdr hdr
;
703 if (fread (&hdr
, 1, sizeof (hdr
), f
) == sizeof (hdr
)
704 && hdr
.magic
== ELFHINTS_MAGIC
707 if (fseek (f
, hdr
.strtab
+ hdr
.dirlist
, SEEK_SET
) != -1)
711 b
= xmalloc (hdr
.dirlistlen
+ 1);
712 if (fread (b
, 1, hdr
.dirlistlen
+ 1, f
) ==
714 ld_elf_hints
= ldelf_add_sysroot (b
);
725 if (ld_elf_hints
== NULL
)
729 needed
.name
= l
->name
;
730 return ldelf_search_needed (ld_elf_hints
, &needed
, force
, FALSE
, elfsize
);
733 /* For a native linker, check the file /etc/ld.so.conf for directories
734 in which we may find shared libraries. /etc/ld.so.conf is really
735 only meaningful on Linux. */
737 struct ldelf_ld_so_conf
744 ldelf_parse_ld_so_conf (struct ldelf_ld_so_conf
*, const char *);
747 ldelf_parse_ld_so_conf_include (struct ldelf_ld_so_conf
*info
,
748 const char *filename
,
756 if (pattern
[0] != '/')
758 char *p
= strrchr (filename
, '/');
759 size_t patlen
= strlen (pattern
) + 1;
761 newp
= xmalloc (p
- filename
+ 1 + patlen
);
762 memcpy (newp
, filename
, p
- filename
+ 1);
763 memcpy (newp
+ (p
- filename
+ 1), pattern
, patlen
);
768 if (glob (pattern
, 0, NULL
, &gl
) == 0)
772 for (i
= 0; i
< gl
.gl_pathc
; ++i
)
773 ldelf_parse_ld_so_conf (info
, gl
.gl_pathv
[i
]);
777 /* If we do not have glob, treat the pattern as a literal filename. */
778 ldelf_parse_ld_so_conf (info
, pattern
);
786 ldelf_parse_ld_so_conf (struct ldelf_ld_so_conf
*info
, const char *filename
)
788 FILE *f
= fopen (filename
, FOPEN_RT
);
796 line
= xmalloc (linelen
);
801 /* Normally this would use getline(3), but we need to be portable. */
802 while ((q
= fgets (p
, linelen
- (p
- line
), f
)) != NULL
803 && strlen (q
) == linelen
- (p
- line
) - 1
804 && line
[linelen
- 2] != '\n')
806 line
= xrealloc (line
, 2 * linelen
);
807 p
= line
+ linelen
- 1;
811 if (q
== NULL
&& p
== line
)
814 p
= strchr (line
, '\n');
818 /* Because the file format does not know any form of quoting we
819 can search forward for the next '#' character and if found
820 make it terminating the line. */
821 p
= strchr (line
, '#');
825 /* Remove leading whitespace. NUL is no whitespace character. */
827 while (*p
== ' ' || *p
== '\f' || *p
== '\r' || *p
== '\t' || *p
== '\v')
830 /* If the line is blank it is ignored. */
834 if (CONST_STRNEQ (p
, "include") && (p
[7] == ' ' || p
[7] == '\t'))
840 while (*p
== ' ' || *p
== '\t')
848 while (*p
!= ' ' && *p
!= '\t' && *p
)
854 ldelf_parse_ld_so_conf_include (info
, filename
, dir
);
861 while (*p
&& *p
!= '=' && *p
!= ' ' && *p
!= '\t' && *p
!= '\f'
862 && *p
!= '\r' && *p
!= '\v')
865 while (p
!= dir
&& p
[-1] == '/')
867 if (info
->path
== NULL
)
869 info
->alloc
= p
- dir
+ 1 + 256;
870 info
->path
= xmalloc (info
->alloc
);
875 if (info
->len
+ 1 + (p
- dir
) >= info
->alloc
)
877 info
->alloc
+= p
- dir
+ 256;
878 info
->path
= xrealloc (info
->path
, info
->alloc
);
880 info
->path
[info
->len
++] = config
.rpath_separator
;
882 memcpy (info
->path
+ info
->len
, dir
, p
- dir
);
883 info
->len
+= p
- dir
;
884 info
->path
[info
->len
] = '\0';
894 ldelf_check_ld_so_conf (const struct bfd_link_needed_list
*l
, int force
,
897 static bfd_boolean initialized
;
898 static const char *ld_so_conf
;
899 struct dt_needed needed
;
904 struct ldelf_ld_so_conf info
;
907 info
.len
= info
.alloc
= 0;
908 tmppath
= concat (ld_sysroot
, "${prefix}/etc/ld.so.conf",
909 (const char *) NULL
);
910 if (!ldelf_parse_ld_so_conf (&info
, tmppath
))
913 tmppath
= concat (ld_sysroot
, "/etc/ld.so.conf",
914 (const char *) NULL
);
915 ldelf_parse_ld_so_conf (&info
, tmppath
);
921 ld_so_conf
= ldelf_add_sysroot (info
.path
);
927 if (ld_so_conf
== NULL
)
932 needed
.name
= l
->name
;
933 return ldelf_search_needed (ld_so_conf
, &needed
, force
, TRUE
, elfsize
);
936 /* See if an input file matches a DT_NEEDED entry by name. */
939 ldelf_check_needed (lang_input_statement_type
*s
)
943 /* Stop looking if we've found a loaded lib. */
944 if (global_found
!= NULL
945 && (bfd_elf_get_dyn_lib_class (global_found
->the_bfd
)
946 & DYN_AS_NEEDED
) == 0)
949 if (s
->filename
== NULL
|| s
->the_bfd
== NULL
)
952 /* Don't look for a second non-loaded as-needed lib. */
953 if (global_found
!= NULL
954 && (bfd_elf_get_dyn_lib_class (s
->the_bfd
) & DYN_AS_NEEDED
) != 0)
957 if (filename_cmp (s
->filename
, global_needed
->name
) == 0)
963 if (s
->flags
.search_dirs
)
965 const char *f
= strrchr (s
->filename
, '/');
967 && filename_cmp (f
+ 1, global_needed
->name
) == 0)
974 soname
= bfd_elf_get_dt_soname (s
->the_bfd
);
976 && filename_cmp (soname
, global_needed
->name
) == 0)
983 /* This is called after all the input files have been opened. */
986 ldelf_after_open (int use_libpath
, int native
, int is_linux
, int is_freebsd
,
989 struct bfd_link_needed_list
*needed
, *l
;
990 struct elf_link_hash_table
*htab
;
994 after_open_default ();
996 htab
= elf_hash_table (&link_info
);
997 if (!is_elf_hash_table (htab
))
1000 if (command_line
.out_implib_filename
)
1002 unlink_if_ordinary (command_line
.out_implib_filename
);
1003 link_info
.out_implib_bfd
1004 = bfd_openw (command_line
.out_implib_filename
,
1005 bfd_get_target (link_info
.output_bfd
));
1007 if (link_info
.out_implib_bfd
== NULL
)
1009 einfo (_("%F%P: %s: can't open for writing: %E\n"),
1010 command_line
.out_implib_filename
);
1014 if (ldelf_emit_note_gnu_build_id
!= NULL
)
1016 /* Find an ELF input. */
1017 for (abfd
= link_info
.input_bfds
;
1018 abfd
!= (bfd
*) NULL
; abfd
= abfd
->link
.next
)
1019 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
1020 && bfd_count_sections (abfd
) != 0
1021 && !((lang_input_statement_type
*) abfd
->usrdata
)->flags
.just_syms
)
1024 /* PR 10555: If there are no ELF input files do not try to
1025 create a .note.gnu-build-id section. */
1027 || !ldelf_setup_build_id (abfd
))
1029 free ((char *) ldelf_emit_note_gnu_build_id
);
1030 ldelf_emit_note_gnu_build_id
= NULL
;
1034 get_elf_backend_data (link_info
.output_bfd
)->setup_gnu_properties (&link_info
);
1036 if (bfd_link_relocatable (&link_info
))
1038 if (link_info
.execstack
== !link_info
.noexecstack
)
1040 /* PR ld/16744: If "-z [no]execstack" has been specified on the
1041 command line and we are perfoming a relocatable link then no
1042 PT_GNU_STACK segment will be created and so the
1043 linkinfo.[no]execstack values set in _handle_option() will have no
1044 effect. Instead we create a .note.GNU-stack section in much the
1045 same way as the assembler does with its --[no]execstack option. */
1046 flagword flags
= SEC_READONLY
| (link_info
.execstack
? SEC_CODE
: 0);
1047 (void) bfd_make_section_with_flags (link_info
.input_bfds
,
1048 ".note.GNU-stack", flags
);
1053 if (!link_info
.traditional_format
)
1056 bfd_boolean warn_eh_frame
= FALSE
;
1059 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1063 if (((lang_input_statement_type
*) abfd
->usrdata
)->flags
.just_syms
)
1066 for (s
= abfd
->sections
; s
&& type
< COMPACT_EH_HDR
; s
= s
->next
)
1068 const char *name
= bfd_section_name (s
);
1070 if (bfd_is_abs_section (s
->output_section
))
1072 if (CONST_STRNEQ (name
, ".eh_frame_entry"))
1073 type
= COMPACT_EH_HDR
;
1074 else if (strcmp (name
, ".eh_frame") == 0 && s
->size
> 8)
1075 type
= DWARF2_EH_HDR
;
1084 else if (seen_type
!= type
)
1086 einfo (_("%F%P: compact frame descriptions incompatible with"
1087 " DWARF2 .eh_frame from %pB\n"),
1088 type
== DWARF2_EH_HDR
? abfd
: elfbfd
);
1093 && (type
== COMPACT_EH_HDR
1094 || link_info
.eh_frame_hdr_type
!= 0))
1096 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
1099 warn_eh_frame
= TRUE
;
1103 if (seen_type
== COMPACT_EH_HDR
)
1104 link_info
.eh_frame_hdr_type
= COMPACT_EH_HDR
;
1108 const struct elf_backend_data
*bed
;
1110 bed
= get_elf_backend_data (elfbfd
);
1111 s
= bfd_make_section_with_flags (elfbfd
, ".eh_frame_hdr",
1112 bed
->dynamic_sec_flags
1115 && bfd_set_section_alignment (s
, 2))
1117 htab
->eh_info
.hdr_sec
= s
;
1118 warn_eh_frame
= FALSE
;
1122 einfo (_("%P: warning: cannot create .eh_frame_hdr section,"
1123 " --eh-frame-hdr ignored\n"));
1126 /* Get the list of files which appear in DT_NEEDED entries in
1127 dynamic objects included in the link (often there will be none).
1128 For each such file, we want to track down the corresponding
1129 library, and include the symbol table in the link. This is what
1130 the runtime dynamic linker will do. Tracking the files down here
1131 permits one dynamic object to include another without requiring
1132 special action by the person doing the link. Note that the
1133 needed list can actually grow while we are stepping through this
1135 needed
= bfd_elf_get_needed_list (link_info
.output_bfd
, &link_info
);
1136 for (l
= needed
; l
!= NULL
; l
= l
->next
)
1138 struct bfd_link_needed_list
*ll
;
1139 struct dt_needed n
, nn
;
1142 /* If the lib that needs this one was --as-needed and wasn't
1143 found to be needed, then this lib isn't needed either. */
1145 && (bfd_elf_get_dyn_lib_class (l
->by
) & DYN_AS_NEEDED
) != 0)
1148 /* Skip the lib if --no-copy-dt-needed-entries and
1149 --allow-shlib-undefined is in effect. */
1151 && link_info
.unresolved_syms_in_shared_libs
== RM_IGNORE
1152 && (bfd_elf_get_dyn_lib_class (l
->by
) & DYN_NO_ADD_NEEDED
) != 0)
1155 /* If we've already seen this file, skip it. */
1156 for (ll
= needed
; ll
!= l
; ll
= ll
->next
)
1158 || (bfd_elf_get_dyn_lib_class (ll
->by
) & DYN_AS_NEEDED
) == 0)
1159 && strcmp (ll
->name
, l
->name
) == 0)
1164 /* See if this file was included in the link explicitly. */
1166 global_found
= NULL
;
1167 lang_for_each_input_file (ldelf_check_needed
);
1168 if (global_found
!= NULL
1169 && (bfd_elf_get_dyn_lib_class (global_found
->the_bfd
)
1170 & DYN_AS_NEEDED
) == 0)
1177 info_msg (_("%s needed by %pB\n"), l
->name
, l
->by
);
1179 /* As-needed libs specified on the command line (or linker script)
1180 take priority over libs found in search dirs. */
1181 if (global_found
!= NULL
)
1183 nn
.name
= global_found
->filename
;
1184 if (ldelf_try_needed (&nn
, TRUE
, is_linux
))
1188 /* We need to find this file and include the symbol table. We
1189 want to search for the file in the same way that the dynamic
1190 linker will search. That means that we want to use
1191 rpath_link, rpath, then the environment variable
1192 LD_LIBRARY_PATH (native only), then the DT_RPATH/DT_RUNPATH
1193 entries (native only), then the linker script LIB_SEARCH_DIRS.
1194 We do not search using the -L arguments.
1196 We search twice. The first time, we skip objects which may
1197 introduce version mismatches. The second time, we force
1198 their use. See ldelf_vercheck comment. */
1199 for (force
= 0; force
< 2; force
++)
1202 search_dirs_type
*search
;
1204 struct bfd_link_needed_list
*rp
;
1207 if (ldelf_search_needed (command_line
.rpath_link
, &n
, force
,
1213 path
= command_line
.rpath
;
1216 path
= ldelf_add_sysroot (path
);
1217 found
= ldelf_search_needed (path
, &n
, force
,
1219 free ((char *) path
);
1226 if (command_line
.rpath_link
== NULL
1227 && command_line
.rpath
== NULL
)
1229 path
= (const char *) getenv ("LD_RUN_PATH");
1231 && ldelf_search_needed (path
, &n
, force
,
1235 path
= (const char *) getenv ("LD_LIBRARY_PATH");
1237 && ldelf_search_needed (path
, &n
, force
,
1244 rp
= bfd_elf_get_runpath_list (link_info
.output_bfd
, &link_info
);
1245 for (; !found
&& rp
!= NULL
; rp
= rp
->next
)
1247 path
= ldelf_add_sysroot (rp
->name
);
1248 found
= (rp
->by
== l
->by
1249 && ldelf_search_needed (path
, &n
, force
,
1250 is_linux
, elfsize
));
1251 free ((char *) path
);
1257 && ldelf_check_ld_elf_hints (l
, force
, elfsize
))
1261 && ldelf_check_ld_so_conf (l
, force
, elfsize
))
1265 len
= strlen (l
->name
);
1266 for (search
= search_head
; search
!= NULL
; search
= search
->next
)
1270 if (search
->cmdline
)
1272 filename
= (char *) xmalloc (strlen (search
->name
) + len
+ 2);
1273 sprintf (filename
, "%s/%s", search
->name
, l
->name
);
1275 if (ldelf_try_needed (&nn
, force
, is_linux
))
1286 einfo (_("%P: warning: %s, needed by %pB, not found "
1287 "(try using -rpath or -rpath-link)\n"),
1291 if (link_info
.eh_frame_hdr_type
== COMPACT_EH_HDR
)
1292 if (!bfd_elf_parse_eh_frame_entries (NULL
, &link_info
))
1293 einfo (_("%F%P: failed to parse EH frame entries\n"));
1296 static bfd_size_type
1297 id_note_section_size (bfd
*abfd ATTRIBUTE_UNUSED
)
1299 const char *style
= ldelf_emit_note_gnu_build_id
;
1301 bfd_size_type build_id_size
;
1303 size
= offsetof (Elf_External_Note
, name
[sizeof "GNU"]);
1304 size
= (size
+ 3) & -(bfd_size_type
) 4;
1306 build_id_size
= compute_build_id_size (style
);
1308 size
+= build_id_size
;
1316 write_build_id (bfd
*abfd
)
1318 const struct elf_backend_data
*bed
= get_elf_backend_data (abfd
);
1319 struct elf_obj_tdata
*t
= elf_tdata (abfd
);
1322 Elf_Internal_Shdr
*i_shdr
;
1323 unsigned char *contents
, *id_bits
;
1326 Elf_External_Note
*e_note
;
1328 style
= t
->o
->build_id
.style
;
1329 asec
= t
->o
->build_id
.sec
;
1330 if (bfd_is_abs_section (asec
->output_section
))
1332 einfo (_("%P: warning: .note.gnu.build-id section discarded,"
1333 " --build-id ignored\n"));
1336 i_shdr
= &elf_section_data (asec
->output_section
)->this_hdr
;
1338 if (i_shdr
->contents
== NULL
)
1340 if (asec
->contents
== NULL
)
1341 asec
->contents
= (unsigned char *) xmalloc (asec
->size
);
1342 contents
= asec
->contents
;
1345 contents
= i_shdr
->contents
+ asec
->output_offset
;
1347 e_note
= (Elf_External_Note
*) contents
;
1348 size
= offsetof (Elf_External_Note
, name
[sizeof "GNU"]);
1349 size
= (size
+ 3) & -(bfd_size_type
) 4;
1350 id_bits
= contents
+ size
;
1351 size
= asec
->size
- size
;
1353 bfd_h_put_32 (abfd
, sizeof "GNU", &e_note
->namesz
);
1354 bfd_h_put_32 (abfd
, size
, &e_note
->descsz
);
1355 bfd_h_put_32 (abfd
, NT_GNU_BUILD_ID
, &e_note
->type
);
1356 memcpy (e_note
->name
, "GNU", sizeof "GNU");
1358 generate_build_id (abfd
, style
, bed
->s
->checksum_contents
, id_bits
, size
);
1360 position
= i_shdr
->sh_offset
+ asec
->output_offset
;
1362 return (bfd_seek (abfd
, position
, SEEK_SET
) == 0
1363 && bfd_bwrite (contents
, size
, abfd
) == size
);
1366 /* Make .note.gnu.build-id section, and set up elf_tdata->build_id. */
1369 ldelf_setup_build_id (bfd
*ibfd
)
1375 size
= id_note_section_size (ibfd
);
1378 einfo (_("%P: warning: unrecognized --build-id style ignored\n"));
1382 flags
= (SEC_ALLOC
| SEC_LOAD
| SEC_IN_MEMORY
1383 | SEC_LINKER_CREATED
| SEC_READONLY
| SEC_DATA
);
1384 s
= bfd_make_section_with_flags (ibfd
, ".note.gnu.build-id", flags
);
1385 if (s
!= NULL
&& bfd_set_section_alignment (s
, 2))
1387 struct elf_obj_tdata
*t
= elf_tdata (link_info
.output_bfd
);
1388 t
->o
->build_id
.after_write_object_contents
= &write_build_id
;
1389 t
->o
->build_id
.style
= ldelf_emit_note_gnu_build_id
;
1390 t
->o
->build_id
.sec
= s
;
1391 elf_section_type (s
) = SHT_NOTE
;
1396 einfo (_("%P: warning: cannot create .note.gnu.build-id section,"
1397 " --build-id ignored\n"));
1401 /* Look through an expression for an assignment statement. */
1404 ldelf_find_exp_assignment (etree_type
*exp
)
1406 bfd_boolean provide
= FALSE
;
1408 switch (exp
->type
.node_class
)
1411 case etree_provided
:
1415 /* We call record_link_assignment even if the symbol is defined.
1416 This is because if it is defined by a dynamic object, we
1417 actually want to use the value defined by the linker script,
1418 not the value from the dynamic object (because we are setting
1419 symbols like etext). If the symbol is defined by a regular
1420 object, then, as it happens, calling record_link_assignment
1422 if (strcmp (exp
->assign
.dst
, ".") != 0)
1424 if (!bfd_elf_record_link_assignment (link_info
.output_bfd
,
1426 exp
->assign
.dst
, provide
,
1427 exp
->assign
.hidden
))
1428 einfo (_("%F%P: failed to record assignment to %s: %E\n"),
1431 ldelf_find_exp_assignment (exp
->assign
.src
);
1435 ldelf_find_exp_assignment (exp
->binary
.lhs
);
1436 ldelf_find_exp_assignment (exp
->binary
.rhs
);
1440 ldelf_find_exp_assignment (exp
->trinary
.cond
);
1441 ldelf_find_exp_assignment (exp
->trinary
.lhs
);
1442 ldelf_find_exp_assignment (exp
->trinary
.rhs
);
1446 ldelf_find_exp_assignment (exp
->unary
.child
);
1454 /* This is called by the before_allocation routine via
1455 lang_for_each_statement. It locates any assignment statements, and
1456 tells the ELF backend about them, in case they are assignments to
1457 symbols which are referred to by dynamic objects. */
1460 ldelf_find_statement_assignment (lang_statement_union_type
*s
)
1462 if (s
->header
.type
== lang_assignment_statement_enum
)
1463 ldelf_find_exp_assignment (s
->assignment_statement
.exp
);
1466 /* Used by before_allocation and handle_option. */
1469 ldelf_append_to_separated_string (char **to
, char *op_arg
)
1472 *to
= xstrdup (op_arg
);
1475 size_t to_len
= strlen (*to
);
1476 size_t op_arg_len
= strlen (op_arg
);
1480 /* First see whether OPTARG is already in the path. */
1483 if (strncmp (op_arg
, cp
, op_arg_len
) == 0
1484 && (cp
[op_arg_len
] == 0
1485 || cp
[op_arg_len
] == config
.rpath_separator
))
1489 /* Not yet found. */
1490 cp
= strchr (cp
, config
.rpath_separator
);
1498 buf
= xmalloc (to_len
+ op_arg_len
+ 2);
1499 sprintf (buf
, "%s%c%s", *to
,
1500 config
.rpath_separator
, op_arg
);
1507 /* This is called after the sections have been attached to output
1508 sections, but before any sizes or addresses have been set. */
1511 ldelf_before_allocation (char *audit
, char *depaudit
,
1512 const char *default_interpreter_name
)
1517 struct bfd_link_hash_entry
*ehdr_start
= NULL
;
1518 unsigned char ehdr_start_save_type
= 0;
1519 char ehdr_start_save_u
[sizeof ehdr_start
->u
1520 - sizeof ehdr_start
->u
.def
.next
] = "";
1522 if (is_elf_hash_table (link_info
.hash
))
1524 _bfd_elf_tls_setup (link_info
.output_bfd
, &link_info
);
1526 /* Make __ehdr_start hidden if it has been referenced, to
1527 prevent the symbol from being dynamic. */
1528 if (!bfd_link_relocatable (&link_info
))
1530 struct elf_link_hash_table
*htab
= elf_hash_table (&link_info
);
1531 struct elf_link_hash_entry
*h
1532 = elf_link_hash_lookup (htab
, "__ehdr_start", FALSE
, FALSE
, TRUE
);
1534 /* Only adjust the export class if the symbol was referenced
1535 and not defined, otherwise leave it alone. */
1537 && (h
->root
.type
== bfd_link_hash_new
1538 || h
->root
.type
== bfd_link_hash_undefined
1539 || h
->root
.type
== bfd_link_hash_undefweak
1540 || h
->root
.type
== bfd_link_hash_common
))
1542 const struct elf_backend_data
*bed
;
1543 bed
= get_elf_backend_data (link_info
.output_bfd
);
1544 (*bed
->elf_backend_hide_symbol
) (&link_info
, h
, TRUE
);
1545 if (ELF_ST_VISIBILITY (h
->other
) != STV_INTERNAL
)
1546 h
->other
= (h
->other
& ~ELF_ST_VISIBILITY (-1)) | STV_HIDDEN
;
1547 /* Don't leave the symbol undefined. Undefined hidden
1548 symbols typically won't have dynamic relocations, but
1549 we most likely will need dynamic relocations for
1550 __ehdr_start if we are building a PIE or shared
1552 ehdr_start
= &h
->root
;
1553 ehdr_start_save_type
= ehdr_start
->type
;
1554 memcpy (ehdr_start_save_u
,
1555 (char *) &ehdr_start
->u
+ sizeof ehdr_start
->u
.def
.next
,
1556 sizeof ehdr_start_save_u
);
1557 ehdr_start
->type
= bfd_link_hash_defined
;
1558 ehdr_start
->u
.def
.section
= bfd_abs_section_ptr
;
1559 ehdr_start
->u
.def
.value
= 0;
1563 /* If we are going to make any variable assignments, we need to
1564 let the ELF backend know about them in case the variables are
1565 referred to by dynamic objects. */
1566 lang_for_each_statement (ldelf_find_statement_assignment
);
1569 /* Let the ELF backend work out the sizes of any sections required
1570 by dynamic linking. */
1571 rpath
= command_line
.rpath
;
1573 rpath
= (const char *) getenv ("LD_RUN_PATH");
1575 for (abfd
= link_info
.input_bfds
; abfd
; abfd
= abfd
->link
.next
)
1576 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
1578 const char *audit_libs
= elf_dt_audit (abfd
);
1580 /* If the input bfd contains an audit entry, we need to add it as
1581 a dep audit entry. */
1582 if (audit_libs
&& *audit_libs
!= '\0')
1584 char *cp
= xstrdup (audit_libs
);
1588 char *cp2
= strchr (cp
, config
.rpath_separator
);
1596 if (cp
!= NULL
&& *cp
!= '\0')
1597 ldelf_append_to_separated_string (&depaudit
, cp
);
1599 cp
= more
? ++cp2
: NULL
;
1605 if (! (bfd_elf_size_dynamic_sections
1606 (link_info
.output_bfd
, command_line
.soname
, rpath
,
1607 command_line
.filter_shlib
, audit
, depaudit
,
1608 (const char * const *) command_line
.auxiliary_filters
,
1609 &link_info
, &sinterp
)))
1610 einfo (_("%F%P: failed to set dynamic section sizes: %E\n"));
1612 if (sinterp
!= NULL
)
1614 /* Let the user override the dynamic linker we are using. */
1615 if (command_line
.interpreter
!= NULL
)
1616 default_interpreter_name
= command_line
.interpreter
;
1617 if (default_interpreter_name
!= NULL
)
1619 sinterp
->contents
= (bfd_byte
*) default_interpreter_name
;
1620 sinterp
->size
= strlen ((char *) sinterp
->contents
) + 1;
1624 /* Look for any sections named .gnu.warning. As a GNU extensions,
1625 we treat such sections as containing warning messages. We print
1626 out the warning message, and then zero out the section size so
1627 that it does not get copied into the output file. */
1630 LANG_FOR_EACH_INPUT_STATEMENT (is
)
1636 if (is
->flags
.just_syms
)
1639 s
= bfd_get_section_by_name (is
->the_bfd
, ".gnu.warning");
1644 msg
= (char *) xmalloc ((size_t) (sz
+ 1));
1645 if (! bfd_get_section_contents (is
->the_bfd
, s
, msg
,
1647 einfo (_("%F%P: %pB: can't read contents of section .gnu.warning: %E\n"),
1650 (*link_info
.callbacks
->warning
) (&link_info
, msg
,
1651 (const char *) NULL
, is
->the_bfd
,
1652 (asection
*) NULL
, (bfd_vma
) 0);
1655 /* Clobber the section size, so that we don't waste space
1656 copying the warning into the output file. If we've already
1657 sized the output section, adjust its size. The adjustment
1658 is on rawsize because targets that size sections early will
1659 have called lang_reset_memory_regions after sizing. */
1660 if (s
->output_section
!= NULL
1661 && s
->output_section
->rawsize
>= s
->size
)
1662 s
->output_section
->rawsize
-= s
->size
;
1666 /* Also set SEC_EXCLUDE, so that local symbols defined in the
1667 warning section don't get copied to the output. */
1668 s
->flags
|= SEC_EXCLUDE
| SEC_KEEP
;
1672 before_allocation_default ();
1674 if (!bfd_elf_size_dynsym_hash_dynstr (link_info
.output_bfd
, &link_info
))
1675 einfo (_("%F%P: failed to set dynamic section sizes: %E\n"));
1677 if (ehdr_start
!= NULL
)
1679 /* If we twiddled __ehdr_start to defined earlier, put it back
1681 ehdr_start
->type
= ehdr_start_save_type
;
1682 memcpy ((char *) &ehdr_start
->u
+ sizeof ehdr_start
->u
.def
.next
,
1684 sizeof ehdr_start_save_u
);
1687 /* Try to open a dynamic archive. This is where we know that ELF
1688 dynamic libraries have an extension of .so (or .sl on oddball systems
1692 ldelf_open_dynamic_archive (const char *arch
, search_dirs_type
*search
,
1693 lang_input_statement_type
*entry
)
1695 const char *filename
;
1698 bfd_boolean opened
= FALSE
;
1700 if (! entry
->flags
.maybe_archive
)
1703 filename
= entry
->filename
;
1704 len
= strlen (search
->name
) + strlen (filename
);
1705 if (entry
->flags
.full_name_provided
)
1708 string
= (char *) xmalloc (len
);
1709 sprintf (string
, "%s/%s", search
->name
, filename
);
1715 len
+= strlen (arch
) + sizeof "/lib.so";
1716 #ifdef EXTRA_SHLIB_EXTENSION
1717 xlen
= (strlen (EXTRA_SHLIB_EXTENSION
) > 3
1718 ? strlen (EXTRA_SHLIB_EXTENSION
) - 3
1721 string
= (char *) xmalloc (len
+ xlen
);
1722 sprintf (string
, "%s/lib%s%s.so", search
->name
, filename
, arch
);
1723 #ifdef EXTRA_SHLIB_EXTENSION
1724 /* Try the .so extension first. If that fails build a new filename
1725 using EXTRA_SHLIB_EXTENSION. */
1726 opened
= ldfile_try_open_bfd (string
, entry
);
1728 strcpy (string
+ len
- 4, EXTRA_SHLIB_EXTENSION
);
1732 if (!opened
&& !ldfile_try_open_bfd (string
, entry
))
1738 entry
->filename
= string
;
1740 /* We have found a dynamic object to include in the link. The ELF
1741 backend linker will create a DT_NEEDED entry in the .dynamic
1742 section naming this file. If this file includes a DT_SONAME
1743 entry, it will be used. Otherwise, the ELF linker will just use
1744 the name of the file. For an archive found by searching, like
1745 this one, the DT_NEEDED entry should consist of just the name of
1746 the file, without the path information used to find it. Note
1747 that we only need to do this if we have a dynamic object; an
1748 archive will never be referenced by a DT_NEEDED entry.
1750 FIXME: This approach--using bfd_elf_set_dt_needed_name--is not
1751 very pretty. I haven't been able to think of anything that is
1753 if (bfd_check_format (entry
->the_bfd
, bfd_object
)
1754 && (entry
->the_bfd
->flags
& DYNAMIC
) != 0)
1756 ASSERT (entry
->flags
.maybe_archive
&& entry
->flags
.search_dirs
);
1758 /* Rather than duplicating the logic above. Just use the
1759 filename we recorded earlier. */
1761 if (!entry
->flags
.full_name_provided
)
1762 filename
= lbasename (entry
->filename
);
1763 bfd_elf_set_dt_needed_name (entry
->the_bfd
, filename
);
1769 /* A variant of lang_output_section_find used by place_orphan. */
1771 static lang_output_section_statement_type
*
1772 output_rel_find (int isdyn
, int rela
)
1774 lang_output_section_statement_type
*lookup
;
1775 lang_output_section_statement_type
*last
= NULL
;
1776 lang_output_section_statement_type
*last_alloc
= NULL
;
1777 lang_output_section_statement_type
*last_ro_alloc
= NULL
;
1778 lang_output_section_statement_type
*last_rel
= NULL
;
1779 lang_output_section_statement_type
*last_rel_alloc
= NULL
;
1781 for (lookup
= &lang_os_list
.head
->output_section_statement
;
1783 lookup
= lookup
->next
)
1785 if (lookup
->constraint
>= 0
1786 && CONST_STRNEQ (lookup
->name
, ".rel"))
1788 int lookrela
= lookup
->name
[4] == 'a';
1790 /* .rel.dyn must come before all other reloc sections, to suit
1795 /* Don't place after .rel.plt as doing so results in wrong
1797 if (strcmp (".plt", lookup
->name
+ 4 + lookrela
) == 0)
1800 if (rela
== lookrela
|| last_rel
== NULL
)
1802 if ((rela
== lookrela
|| last_rel_alloc
== NULL
)
1803 && lookup
->bfd_section
!= NULL
1804 && (lookup
->bfd_section
->flags
& SEC_ALLOC
) != 0)
1805 last_rel_alloc
= lookup
;
1809 if (lookup
->bfd_section
!= NULL
1810 && (lookup
->bfd_section
->flags
& SEC_ALLOC
) != 0)
1812 last_alloc
= lookup
;
1813 if ((lookup
->bfd_section
->flags
& SEC_READONLY
) != 0)
1814 last_ro_alloc
= lookup
;
1819 return last_rel_alloc
;
1825 return last_ro_alloc
;
1833 /* Return whether IN is suitable to be part of OUT. */
1836 elf_orphan_compatible (asection
*in
, asection
*out
)
1838 /* Non-zero sh_info implies a section with SHF_INFO_LINK with
1839 unknown semantics for the generic linker, or a SHT_REL/SHT_RELA
1840 section where sh_info specifies a symbol table. (We won't see
1841 SHT_GROUP, SHT_SYMTAB or SHT_DYNSYM sections here.) We clearly
1842 can't merge SHT_REL/SHT_RELA using differing symbol tables, and
1843 shouldn't merge sections with differing unknown semantics. */
1844 if (elf_section_data (out
)->this_hdr
.sh_info
1845 != elf_section_data (in
)->this_hdr
.sh_info
)
1847 /* We can't merge with member of output section group nor merge two
1848 sections with differing SHF_EXCLUDE when doing a relocatable link.
1850 if (bfd_link_relocatable (&link_info
)
1851 && (elf_next_in_group (out
) != NULL
1852 || ((elf_section_flags (out
) ^ elf_section_flags (in
))
1853 & SHF_EXCLUDE
) != 0))
1855 return _bfd_elf_match_sections_by_type (link_info
.output_bfd
, out
,
1859 /* Place an orphan section. We use this to put random SHF_ALLOC
1860 sections in the right segment. */
1862 lang_output_section_statement_type
*
1863 ldelf_place_orphan (asection
*s
, const char *secname
, int constraint
)
1865 static struct orphan_save hold
[] =
1868 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_CODE
,
1871 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1874 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
| SEC_THREAD_LOCAL
,
1877 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
,
1883 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1886 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_READONLY
| SEC_DATA
,
1889 SEC_HAS_CONTENTS
| SEC_ALLOC
| SEC_LOAD
| SEC_DATA
| SEC_SMALL_DATA
,
1895 enum orphan_save_index
1907 static int orphan_init_done
= 0;
1908 struct orphan_save
*place
;
1909 lang_output_section_statement_type
*after
;
1910 lang_output_section_statement_type
*os
;
1911 lang_output_section_statement_type
*match_by_name
= NULL
;
1913 int elfinput
= s
->owner
->xvec
->flavour
== bfd_target_elf_flavour
;
1914 int elfoutput
= link_info
.output_bfd
->xvec
->flavour
== bfd_target_elf_flavour
;
1915 unsigned int sh_type
= elfinput
? elf_section_type (s
) : SHT_NULL
;
1919 if (!bfd_link_relocatable (&link_info
)
1920 && link_info
.combreloc
1921 && (s
->flags
& SEC_ALLOC
))
1927 secname
= ".rela.dyn";
1931 secname
= ".rel.dyn";
1937 else if (CONST_STRNEQ (secname
, ".rel"))
1939 secname
= secname
[4] == 'a' ? ".rela.dyn" : ".rel.dyn";
1944 if (!bfd_link_relocatable (&link_info
)
1947 && (s
->flags
& SEC_ALLOC
) != 0
1948 && (elf_tdata (s
->owner
)->has_gnu_osabi
& elf_gnu_osabi_mbind
) != 0
1949 && (elf_section_flags (s
) & SHF_GNU_MBIND
) != 0)
1951 /* Find the output mbind section with the same type, attributes
1952 and sh_info field. */
1953 for (os
= &lang_os_list
.head
->output_section_statement
;
1956 if (os
->bfd_section
!= NULL
1957 && !bfd_is_abs_section (os
->bfd_section
)
1958 && (elf_section_flags (os
->bfd_section
) & SHF_GNU_MBIND
) != 0
1959 && ((s
->flags
& (SEC_ALLOC
1964 == (os
->bfd_section
->flags
& (SEC_ALLOC
1969 && (elf_section_data (os
->bfd_section
)->this_hdr
.sh_info
1970 == elf_section_data (s
)->this_hdr
.sh_info
))
1972 lang_add_section (&os
->children
, s
, NULL
, os
);
1976 /* Create the output mbind section with the ".mbind." prefix
1978 if ((s
->flags
& (SEC_LOAD
| SEC_HAS_CONTENTS
)) == 0)
1979 secname
= ".mbind.bss";
1980 else if ((s
->flags
& SEC_READONLY
) == 0)
1981 secname
= ".mbind.data";
1982 else if ((s
->flags
& SEC_CODE
) == 0)
1983 secname
= ".mbind.rodata";
1985 secname
= ".mbind.text";
1986 elf_tdata (link_info
.output_bfd
)->has_gnu_osabi
|= elf_gnu_osabi_mbind
;
1989 /* Look through the script to see where to place this section. The
1990 script includes entries added by previous lang_insert_orphan
1991 calls, so this loop puts multiple compatible orphans of the same
1992 name into a single output section. */
1993 if (constraint
== 0)
1994 for (os
= lang_output_section_find (secname
);
1996 os
= next_matching_output_section_statement (os
, 0))
1998 /* If we don't match an existing output section, tell
1999 lang_insert_orphan to create a new output section. */
2000 constraint
= SPECIAL
;
2002 /* Check to see if we already have an output section statement
2003 with this name, and its bfd section has compatible flags.
2004 If the section already exists but does not have any flags
2005 set, then it has been created by the linker, possibly as a
2006 result of a --section-start command line switch. */
2007 if (os
->bfd_section
!= NULL
2008 && (os
->bfd_section
->flags
== 0
2009 || (((s
->flags
^ os
->bfd_section
->flags
)
2010 & (SEC_LOAD
| SEC_ALLOC
)) == 0
2013 || elf_orphan_compatible (s
, os
->bfd_section
)))))
2015 lang_add_section (&os
->children
, s
, NULL
, os
);
2019 /* Save unused output sections in case we can match them
2020 against orphans later. */
2021 if (os
->bfd_section
== NULL
)
2025 /* If we didn't match an active output section, see if we matched an
2026 unused one and use that. */
2029 lang_add_section (&match_by_name
->children
, s
, NULL
, match_by_name
);
2030 return match_by_name
;
2033 if (!orphan_init_done
)
2035 struct orphan_save
*ho
;
2037 for (ho
= hold
; ho
< hold
+ sizeof (hold
) / sizeof (hold
[0]); ++ho
)
2038 if (ho
->name
!= NULL
)
2040 ho
->os
= lang_output_section_find (ho
->name
);
2041 if (ho
->os
!= NULL
&& ho
->os
->flags
== 0)
2042 ho
->os
->flags
= ho
->flags
;
2044 orphan_init_done
= 1;
2047 /* If this is a final link, then always put .gnu.warning.SYMBOL
2048 sections into the .text section to get them out of the way. */
2049 if (bfd_link_executable (&link_info
)
2050 && CONST_STRNEQ (s
->name
, ".gnu.warning.")
2051 && hold
[orphan_text
].os
!= NULL
)
2053 os
= hold
[orphan_text
].os
;
2054 lang_add_section (&os
->children
, s
, NULL
, os
);
2059 if (!bfd_link_relocatable (&link_info
))
2062 while ((nexts
= bfd_get_next_section_by_name (nexts
->owner
, nexts
))
2064 if (nexts
->output_section
== NULL
2065 && (nexts
->flags
& SEC_EXCLUDE
) == 0
2066 && ((nexts
->flags
^ flags
) & (SEC_LOAD
| SEC_ALLOC
)) == 0
2067 && (nexts
->owner
->flags
& DYNAMIC
) == 0
2068 && nexts
->owner
->usrdata
!= NULL
2069 && !(((lang_input_statement_type
*) nexts
->owner
->usrdata
)
2071 && _bfd_elf_match_sections_by_type (nexts
->owner
, nexts
,
2073 flags
= (((flags
^ SEC_READONLY
)
2074 | (nexts
->flags
^ SEC_READONLY
))
2078 /* Decide which segment the section should go in based on the
2079 section name and section flags. We put loadable .note sections
2080 right after the .interp section, so that the PT_NOTE segment is
2081 stored right after the program headers where the OS can read it
2082 in the first page. */
2085 if ((flags
& (SEC_ALLOC
| SEC_DEBUGGING
)) == 0)
2086 place
= &hold
[orphan_nonalloc
];
2087 else if ((flags
& SEC_ALLOC
) == 0)
2089 else if ((flags
& SEC_LOAD
) != 0
2091 ? sh_type
== SHT_NOTE
2092 : CONST_STRNEQ (secname
, ".note")))
2093 place
= &hold
[orphan_interp
];
2094 else if ((flags
& (SEC_LOAD
| SEC_HAS_CONTENTS
| SEC_THREAD_LOCAL
)) == 0)
2095 place
= &hold
[orphan_bss
];
2096 else if ((flags
& SEC_SMALL_DATA
) != 0)
2097 place
= &hold
[orphan_sdata
];
2098 else if ((flags
& SEC_THREAD_LOCAL
) != 0)
2099 place
= &hold
[orphan_tdata
];
2100 else if ((flags
& SEC_READONLY
) == 0)
2101 place
= &hold
[orphan_data
];
2102 else if ((flags
& SEC_LOAD
) != 0
2104 ? sh_type
== SHT_RELA
|| sh_type
== SHT_REL
2105 : CONST_STRNEQ (secname
, ".rel")))
2106 place
= &hold
[orphan_rel
];
2107 else if ((flags
& SEC_CODE
) == 0)
2108 place
= &hold
[orphan_rodata
];
2110 place
= &hold
[orphan_text
];
2115 if (place
->os
== NULL
)
2117 if (place
->name
!= NULL
)
2118 place
->os
= lang_output_section_find (place
->name
);
2121 int rela
= elfinput
? sh_type
== SHT_RELA
: secname
[4] == 'a';
2122 place
->os
= output_rel_find (isdyn
, rela
);
2128 = lang_output_section_find_by_flags (s
, flags
, &place
->os
,
2129 _bfd_elf_match_sections_by_type
);
2131 /* *ABS* is always the first output section statement. */
2132 after
= &lang_os_list
.head
->output_section_statement
;
2135 return lang_insert_orphan (s
, secname
, constraint
, after
, place
, NULL
, NULL
);