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1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
4 @finalout
5 @synindex ky cp
6
7 @c man begin INCLUDE
8 @include bfdver.texi
9 @c man end
10
11 @copying
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2022 Free Software Foundation, Inc.
14
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
21
22 @c man end
23 @end copying
24
25 @dircategory Software development
26 @direntry
27 * Binutils: (binutils). The GNU binary utilities.
28 @end direntry
29
30 @dircategory Individual utilities
31 @direntry
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nm: (binutils)nm. List symbols from object files.
38 * objcopy: (binutils)objcopy. Copy and translate object files.
39 * objdump: (binutils)objdump. Display information from object files.
40 * ranlib: (binutils)ranlib. Generate index to archive contents.
41 * readelf: (binutils)readelf. Display the contents of ELF format files.
42 * size: (binutils)size. List section sizes and total size.
43 * strings: (binutils)strings. List printable strings from files.
44 * strip: (binutils)strip. Discard symbols.
45 * elfedit: (binutils)elfedit. Update ELF header and property of ELF files.
46 * windmc: (binutils)windmc. Generator for Windows message resources.
47 * windres: (binutils)windres. Manipulate Windows resources.
48 @end direntry
49
50 @titlepage
51 @title The @sc{gnu} Binary Utilities
52 @ifset VERSION_PACKAGE
53 @subtitle @value{VERSION_PACKAGE}
54 @end ifset
55 @subtitle Version @value{VERSION}
56 @sp 1
57 @subtitle @value{UPDATED}
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
61 @page
62
63 @tex
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 Texinfo \texinfoversion\par }
66 @end tex
67
68 @vskip 0pt plus 1filll
69 @insertcopying
70 @end titlepage
71 @contents
72
73 @node Top
74 @top Introduction
75
76 @cindex version
77 This brief manual contains documentation for the @sc{gnu} binary
78 utilities
79 @ifset VERSION_PACKAGE
80 @value{VERSION_PACKAGE}
81 @end ifset
82 version @value{VERSION}:
83
84 @iftex
85 @table @code
86 @item ar
87 Create, modify, and extract from archives
88
89 @item nm
90 List symbols from object files
91
92 @item objcopy
93 Copy and translate object files
94
95 @item objdump
96 Display information from object files
97
98 @item ranlib
99 Generate index to archive contents
100
101 @item readelf
102 Display the contents of ELF format files.
103
104 @item size
105 List file section sizes and total size
106
107 @item strings
108 List printable strings from files
109
110 @item strip
111 Discard symbols
112
113 @item elfedit
114 Update the ELF header and program property of ELF files.
115
116 @item c++filt
117 Demangle encoded C++ symbols (on MS-DOS, this program is named
118 @code{cxxfilt})
119
120 @item addr2line
121 Convert addresses or symbol+offset into file names and line numbers
122
123 @item windres
124 Manipulate Windows resources
125
126 @item windmc
127 Generator for Windows message resources
128
129 @item dlltool
130 Create the files needed to build and use Dynamic Link Libraries
131 @end table
132 @end iftex
133
134 This document is distributed under the terms of the GNU Free
135 Documentation License version 1.3. A copy of the license is included
136 in the section entitled ``GNU Free Documentation License''.
137
138 @menu
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * size:: List section sizes and total size
145 * strings:: List printable strings from files
146 * strip:: Discard symbols
147 * c++filt:: Filter to demangle encoded C++ symbols
148 * cxxfilt: c++filt. MS-DOS name for c++filt
149 * addr2line:: Convert addresses or symbol+offset to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update ELF header and property of ELF files
155 * Common Options:: Command-line options for all utilities
156 * Selecting the Target System:: How these utilities determine the target
157 * debuginfod:: Using binutils with debuginfod
158 * Reporting Bugs:: Reporting Bugs
159 * GNU Free Documentation License:: GNU Free Documentation License
160 * Binutils Index:: Binutils Index
161 @end menu
162
163 @node ar
164 @chapter ar
165
166 @kindex ar
167 @cindex archives
168 @cindex collections of files
169
170 @c man title ar create, modify, and extract from archives
171
172 @smallexample
173 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
174 ar -M [ <mri-script ]
175 @end smallexample
176
177 @c man begin DESCRIPTION ar
178
179 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
180 archives. An @dfn{archive} is a single file holding a collection of
181 other files in a structure that makes it possible to retrieve
182 the original individual files (called @dfn{members} of the archive).
183
184 The original files' contents, mode (permissions), timestamp, owner, and
185 group are preserved in the archive, and can be restored on
186 extraction.
187
188 @cindex name length
189 @sc{gnu} @command{ar} can maintain archives whose members have names of any
190 length; however, depending on how @command{ar} is configured on your
191 system, a limit on member-name length may be imposed for compatibility
192 with archive formats maintained with other tools. If it exists, the
193 limit is often 15 characters (typical of formats related to a.out) or 16
194 characters (typical of formats related to coff).
195
196 @cindex libraries
197 @command{ar} is considered a binary utility because archives of this sort
198 are most often used as @dfn{libraries} holding commonly needed
199 subroutines. Since libraries often will depend on other libraries,
200 @command{ar} can also record the dependencies of a library when the
201 @option{--record-libdeps} option is specified.
202
203 @cindex symbol index
204 @command{ar} creates an index to the symbols defined in relocatable
205 object modules in the archive when you specify the modifier @samp{s}.
206 Once created, this index is updated in the archive whenever @command{ar}
207 makes a change to its contents (save for the @samp{q} update operation).
208 An archive with such an index speeds up linking to the library, and
209 allows routines in the library to call each other without regard to
210 their placement in the archive.
211
212 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
213 table. If an archive lacks the table, another form of @command{ar} called
214 @command{ranlib} can be used to add just the table.
215
216 @cindex thin archives
217 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
218 which contains a symbol index and references to the original copies
219 of the member files of the archive. This is useful for building
220 libraries for use within a local build tree, where the relocatable
221 objects are expected to remain available, and copying the contents of
222 each object would only waste time and space.
223
224 An archive can either be @emph{thin} or it can be normal. It cannot
225 be both at the same time. Once an archive is created its format
226 cannot be changed without first deleting it and then creating a new
227 archive in its place.
228
229 Thin archives are also @emph{flattened}, so that adding one thin
230 archive to another thin archive does not nest it, as would happen with
231 a normal archive. Instead the elements of the first archive are added
232 individually to the second archive.
233
234 The paths to the elements of the archive are stored relative to the
235 archive itself.
236
237 @cindex compatibility, @command{ar}
238 @cindex @command{ar} compatibility
239 @sc{gnu} @command{ar} is designed to be compatible with two different
240 facilities. You can control its activity using command-line options,
241 like the different varieties of @command{ar} on Unix systems; or, if you
242 specify the single command-line option @option{-M}, you can control it
243 with a script supplied via standard input, like the MRI ``librarian''
244 program.
245
246 @c man end
247
248 @menu
249 * ar cmdline:: Controlling @command{ar} on the command line
250 * ar scripts:: Controlling @command{ar} with a script
251 @end menu
252
253 @page
254 @node ar cmdline
255 @section Controlling @command{ar} on the Command Line
256
257 @smallexample
258 @c man begin SYNOPSIS ar
259 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@option{--thin}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
260 @c man end
261 @end smallexample
262
263 @cindex Unix compatibility, @command{ar}
264 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
265 arguments to execute: one keyletter specifying the @emph{operation}
266 (optionally accompanied by other keyletters specifying
267 @emph{modifiers}), and the archive name to act on.
268
269 Most operations can also accept further @var{member} arguments,
270 specifying particular files to operate on.
271
272 @c man begin OPTIONS ar
273
274 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
275 flags @var{mod} in any order, within the first command-line argument.
276
277 If you wish, you may begin the first command-line argument with a
278 dash.
279
280 @cindex operations on archive
281 The @var{p} keyletter specifies what operation to execute; it may be
282 any of the following, but you must specify only one of them:
283
284 @table @samp
285 @item d
286 @cindex deleting from archive
287 @emph{Delete} modules from the archive. Specify the names of modules to
288 be deleted as @var{member}@dots{}; the archive is untouched if you
289 specify no files to delete.
290
291 If you specify the @samp{v} modifier, @command{ar} lists each module
292 as it is deleted.
293
294 @item m
295 @cindex moving in archive
296 Use this operation to @emph{move} members in an archive.
297
298 The ordering of members in an archive can make a difference in how
299 programs are linked using the library, if a symbol is defined in more
300 than one member.
301
302 If no modifiers are used with @code{m}, any members you name in the
303 @var{member} arguments are moved to the @emph{end} of the archive;
304 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
305 specified place instead.
306
307 @item p
308 @cindex printing from archive
309 @emph{Print} the specified members of the archive, to the standard
310 output file. If the @samp{v} modifier is specified, show the member
311 name before copying its contents to standard output.
312
313 If you specify no @var{member} arguments, all the files in the archive are
314 printed.
315
316 @item q
317 @cindex quick append to archive
318 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
319 @var{archive}, without checking for replacement.
320
321 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
322 operation; new members are always placed at the end of the archive.
323
324 The modifier @samp{v} makes @command{ar} list each file as it is appended.
325
326 Since the point of this operation is speed, implementations of
327 @command{ar} have the option of not updating the archive's symbol
328 table if one exists. Too many different systems however assume that
329 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
330 rebuild the table even with a quick append.
331
332 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
333 synonym for @samp{r} - replacing already existing files in the
334 archive and appending new ones at the end.
335
336 @item r
337 @cindex replacement in archive
338 Insert the files @var{member}@dots{} into @var{archive} (with
339 @emph{replacement}). This operation differs from @samp{q} in that any
340 previously existing members are deleted if their names match those being
341 added.
342
343 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
344 displays an error message, and leaves undisturbed any existing members
345 of the archive matching that name.
346
347 By default, new members are added at the end of the file; but you may
348 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
349 placement relative to some existing member.
350
351 The modifier @samp{v} used with this operation elicits a line of
352 output for each file inserted, along with one of the letters @samp{a} or
353 @samp{r} to indicate whether the file was appended (no old member
354 deleted) or replaced.
355
356 @item s
357 @cindex ranlib
358 Add an index to the archive, or update it if it already exists. Note
359 this command is an exception to the rule that there can only be one
360 command letter, as it is possible to use it as either a command or a
361 modifier. In either case it does the same thing.
362
363 @item t
364 @cindex contents of archive
365 Display a @emph{table} listing the contents of @var{archive}, or those
366 of the files listed in @var{member}@dots{} that are present in the
367 archive. Normally only the member name is shown, but if the modifier
368 @samp{O} is specified, then the corresponding offset of the member is also
369 displayed. Finally, in order to see the modes (permissions), timestamp,
370 owner, group, and size the @samp{v} modifier should be included.
371
372 If you do not specify a @var{member}, all files in the archive
373 are listed.
374
375 @cindex repeated names in archive
376 @cindex name duplication in archive
377 If there is more than one file with the same name (say, @samp{fie}) in
378 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
379 first instance; to see them all, you must ask for a complete
380 listing---in our example, @samp{ar t b.a}.
381 @c WRS only; per Gumby, this is implementation-dependent, and in a more
382 @c recent case in fact works the other way.
383
384 @item x
385 @cindex extract from archive
386 @emph{Extract} members (named @var{member}) from the archive. You can
387 use the @samp{v} modifier with this operation, to request that
388 @command{ar} list each name as it extracts it.
389
390 If you do not specify a @var{member}, all files in the archive
391 are extracted.
392
393 Files cannot be extracted from a thin archive, and there are
394 restrictions on extracting from archives created with @option{P}: The
395 paths must not be absolute, may not contain @code{..}, and any
396 subdirectories in the paths must exist. If it is desired to avoid
397 these restrictions then used the @option{--output} option to specify
398 an output directory.
399 @end table
400
401 A number of modifiers (@var{mod}) may immediately follow the @var{p}
402 keyletter, to specify variations on an operation's behavior:
403
404 @table @samp
405 @item a
406 @cindex relative placement in archive
407 Add new files @emph{after} an existing member of the
408 archive. If you use the modifier @samp{a}, the name of an existing archive
409 member must be present as the @var{relpos} argument, before the
410 @var{archive} specification.
411
412 @item b
413 Add new files @emph{before} an existing member of the
414 archive. If you use the modifier @samp{b}, the name of an existing archive
415 member must be present as the @var{relpos} argument, before the
416 @var{archive} specification. (same as @samp{i}).
417
418 @item c
419 @cindex creating archives
420 @emph{Create} the archive. The specified @var{archive} is always
421 created if it did not exist, when you request an update. But a warning is
422 issued unless you specify in advance that you expect to create it, by
423 using this modifier.
424
425 @item D
426 @cindex deterministic archives
427 @kindex --enable-deterministic-archives
428 Operate in @emph{deterministic} mode. When adding files and the archive
429 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
430 for all files. When this option is used, if @command{ar} is used with
431 identical options and identical input files, multiple runs will create
432 identical output files regardless of the input files' owners, groups,
433 file modes, or modification times.
434
435 If @file{binutils} was configured with
436 @option{--enable-deterministic-archives}, then this mode is on by default.
437 It can be disabled with the @samp{U} modifier, below.
438
439 @item f
440 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
441 names of any length. This will cause it to create archives which are
442 not compatible with the native @command{ar} program on some systems. If
443 this is a concern, the @samp{f} modifier may be used to truncate file
444 names when putting them in the archive.
445
446 @item i
447 Insert new files @emph{before} an existing member of the
448 archive. If you use the modifier @samp{i}, the name of an existing archive
449 member must be present as the @var{relpos} argument, before the
450 @var{archive} specification. (same as @samp{b}).
451
452 @item l
453 @c This modifier was accepted but not used.
454 @c whaffor ar l modifier??? presumably compat; with
455 @c what???---doc@@cygnus.com, 25jan91
456 Specify dependencies of this library. The dependencies must immediately
457 follow this option character, must use the same syntax as the linker
458 command line, and must be specified within a single argument. I.e., if
459 multiple items are needed, they must be quoted to form a single command
460 line argument. For example @samp{L "-L/usr/local/lib -lmydep1 -lmydep2"}
461
462 @item N
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
466
467 @item o
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
472
473 @item O
474 @cindex offsets of files
475 Display member offsets inside the archive. Use together with the @samp{t}
476 option.
477
478 @item P
479 Use the full path name when matching or storing names in the archive.
480 Archives created with full path names are not POSIX compliant, and
481 thus may not work with tools other than up to date @sc{gnu} tools.
482 Modifying such archives with @sc{gnu} @command{ar} without using
483 @option{P} will remove the full path names unless the archive is a
484 thin archive. Note that @option{P} may be useful when adding files to
485 a thin archive since @option{r} without @option{P} ignores the path
486 when choosing which element to replace. Thus
487 @smallexample
488 ar rcST archive.a subdir/file1 subdir/file2 file1
489 @end smallexample
490 will result in the first @code{subdir/file1} being replaced with
491 @code{file1} from the current directory. Adding @option{P} will
492 prevent this replacement.
493
494 @item s
495 @cindex writing archive index
496 Write an object-file index into the archive, or update an existing one,
497 even if no other change is made to the archive. You may use this modifier
498 flag either with any operation, or alone. Running @samp{ar s} on an
499 archive is equivalent to running @samp{ranlib} on it.
500
501 @item S
502 @cindex not writing archive index
503 Do not generate an archive symbol table. This can speed up building a
504 large library in several steps. The resulting archive can not be used
505 with the linker. In order to build a symbol table, you must omit the
506 @samp{S} modifier on the last execution of @samp{ar}, or you must run
507 @samp{ranlib} on the archive.
508
509 @item T
510 Deprecated alias for @option{--thin}. @option{T} is not recommended because in
511 many ar implementations @option{T} has a different meaning, as specified by
512 X/Open System Interface.
513
514 @item u
515 @cindex updating an archive
516 Normally, @samp{ar r}@dots{} inserts all files
517 listed into the archive. If you would like to insert @emph{only} those
518 of the files you list that are newer than existing members of the same
519 names, use this modifier. The @samp{u} modifier is allowed only for the
520 operation @samp{r} (replace). In particular, the combination @samp{qu} is
521 not allowed, since checking the timestamps would lose any speed
522 advantage from the operation @samp{q}.
523
524 @item U
525 @cindex deterministic archives
526 @kindex --enable-deterministic-archives
527 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
528 of the @samp{D} modifier, above: added files and the archive index will
529 get their actual UID, GID, timestamp, and file mode values.
530
531 This is the default unless @file{binutils} was configured with
532 @option{--enable-deterministic-archives}.
533
534 @item v
535 This modifier requests the @emph{verbose} version of an operation. Many
536 operations display additional information, such as filenames processed,
537 when the modifier @samp{v} is appended.
538
539 @item V
540 This modifier shows the version number of @command{ar}.
541 @end table
542
543 The @command{ar} program also supports some command-line options which
544 are neither modifiers nor actions, but which do change its behaviour
545 in specific ways:
546
547 @table @samp
548 @item --help
549 Displays the list of command-line options supported by @command{ar}
550 and then exits.
551
552 @item --version
553 Displays the version information of @command{ar} and then exits.
554
555 @item -X32_64
556 @command{ar} ignores an initial option spelled @samp{-X32_64}, for
557 compatibility with AIX. The behaviour produced by this option is the
558 default for @sc{gnu} @command{ar}. @command{ar} does not support any
559 of the other @samp{-X} options; in particular, it does not support
560 @option{-X32} which is the default for AIX @command{ar}.
561
562 @item --plugin @var{name}
563 @cindex plugins
564 The optional command-line switch @option{--plugin @var{name}} causes
565 @command{ar} to load the plugin called @var{name} which adds support
566 for more file formats, including object files with link-time
567 optimization information.
568
569 This option is only available if the toolchain has been built with
570 plugin support enabled.
571
572 If @option{--plugin} is not provided, but plugin support has been
573 enabled then @command{ar} iterates over the files in
574 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
575 plugin that claims the object in question is used.
576
577 Please note that this plugin search directory is @emph{not} the one
578 used by @command{ld}'s @option{-plugin} option. In order to make
579 @command{ar} use the linker plugin it must be copied into the
580 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
581 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
582 based compilations it is called @file{LLVMgold.so}. The GCC plugin
583 is always backwards compatible with earlier versions, so it is
584 sufficient to just copy the newest one.
585
586 @item --target @var{target}
587 The optional command-line switch @option{--target @var{bfdname}}
588 specifies that the archive members are in an object code format
589 different from your system's default format. See
590 @xref{Target Selection}, for more information.
591
592 @item --output @var{dirname}
593 The @option{--output} option can be used to specify a path to a
594 directory into which archive members should be extracted. If this
595 option is not specified then the current directory will be used.
596
597 Note - although the presence of this option does imply a @option{x}
598 extraction operation that option must still be included on the command
599 line.
600
601 @item --record-libdeps @var{libdeps}
602 The @option{--record-libdeps} option is identical to the @option{l} modifier,
603 just handled in long form.
604
605 @item --thin
606 @cindex creating thin archive
607 Make the specified @var{archive} a @emph{thin} archive. If it already
608 exists and is a regular archive, the existing members must be present
609 in the same directory as @var{archive}.
610
611 @end table
612 @c man end
613
614 @ignore
615 @c man begin SEEALSO ar
616 nm(1), ranlib(1), and the Info entries for @file{binutils}.
617 @c man end
618 @end ignore
619
620 @node ar scripts
621 @section Controlling @command{ar} with a Script
622
623 @smallexample
624 ar -M [ <@var{script} ]
625 @end smallexample
626
627 @cindex MRI compatibility, @command{ar}
628 @cindex scripts, @command{ar}
629 If you use the single command-line option @samp{-M} with @command{ar}, you
630 can control its operation with a rudimentary command language. This
631 form of @command{ar} operates interactively if standard input is coming
632 directly from a terminal. During interactive use, @command{ar} prompts for
633 input (the prompt is @samp{AR >}), and continues executing even after
634 errors. If you redirect standard input to a script file, no prompts are
635 issued, and @command{ar} abandons execution (with a nonzero exit code)
636 on any error.
637
638 The @command{ar} command language is @emph{not} designed to be equivalent
639 to the command-line options; in fact, it provides somewhat less control
640 over archives. The only purpose of the command language is to ease the
641 transition to @sc{gnu} @command{ar} for developers who already have scripts
642 written for the MRI ``librarian'' program.
643
644 The syntax for the @command{ar} command language is straightforward:
645 @itemize @bullet
646 @item
647 commands are recognized in upper or lower case; for example, @code{LIST}
648 is the same as @code{list}. In the following descriptions, commands are
649 shown in upper case for clarity.
650
651 @item
652 a single command may appear on each line; it is the first word on the
653 line.
654
655 @item
656 empty lines are allowed, and have no effect.
657
658 @item
659 comments are allowed; text after either of the characters @samp{*}
660 or @samp{;} is ignored.
661
662 @item
663 Whenever you use a list of names as part of the argument to an @command{ar}
664 command, you can separate the individual names with either commas or
665 blanks. Commas are shown in the explanations below, for clarity.
666
667 @item
668 @samp{+} is used as a line continuation character; if @samp{+} appears
669 at the end of a line, the text on the following line is considered part
670 of the current command.
671 @end itemize
672
673 Here are the commands you can use in @command{ar} scripts, or when using
674 @command{ar} interactively. Three of them have special significance:
675
676 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
677 a temporary file required for most of the other commands.
678
679 @code{SAVE} commits the changes so far specified by the script. Prior
680 to @code{SAVE}, commands affect only the temporary copy of the current
681 archive.
682
683 @table @code
684 @item ADDLIB @var{archive}
685 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
686 Add all the contents of @var{archive} (or, if specified, each named
687 @var{module} from @var{archive}) to the current archive.
688
689 Requires prior use of @code{OPEN} or @code{CREATE}.
690
691 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
692 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
693 @c else like "ar q..."
694 Add each named @var{member} as a module in the current archive.
695
696 Requires prior use of @code{OPEN} or @code{CREATE}.
697
698 @item CLEAR
699 Discard the contents of the current archive, canceling the effect of
700 any operations since the last @code{SAVE}. May be executed (with no
701 effect) even if no current archive is specified.
702
703 @item CREATE @var{archive}
704 Creates an archive, and makes it the current archive (required for many
705 other commands). The new archive is created with a temporary name; it
706 is not actually saved as @var{archive} until you use @code{SAVE}.
707 You can overwrite existing archives; similarly, the contents of any
708 existing file named @var{archive} will not be destroyed until @code{SAVE}.
709
710 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
711 Delete each listed @var{module} from the current archive; equivalent to
712 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
713
714 Requires prior use of @code{OPEN} or @code{CREATE}.
715
716 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
717 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
718 List each named @var{module} present in @var{archive}. The separate
719 command @code{VERBOSE} specifies the form of the output: when verbose
720 output is off, output is like that of @samp{ar -t @var{archive}
721 @var{module}@dots{}}. When verbose output is on, the listing is like
722 @samp{ar -tv @var{archive} @var{module}@dots{}}.
723
724 Output normally goes to the standard output stream; however, if you
725 specify @var{outputfile} as a final argument, @command{ar} directs the
726 output to that file.
727
728 @item END
729 Exit from @command{ar}, with a @code{0} exit code to indicate successful
730 completion. This command does not save the output file; if you have
731 changed the current archive since the last @code{SAVE} command, those
732 changes are lost.
733
734 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
735 Extract each named @var{module} from the current archive, writing them
736 into the current directory as separate files. Equivalent to @samp{ar -x
737 @var{archive} @var{module}@dots{}}.
738
739 Requires prior use of @code{OPEN} or @code{CREATE}.
740
741 @ignore
742 @c FIXME Tokens but no commands???
743 @item FULLDIR
744
745 @item HELP
746 @end ignore
747
748 @item LIST
749 Display full contents of the current archive, in ``verbose'' style
750 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
751 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
752 enhancement, rather than present for MRI compatibility.)
753
754 Requires prior use of @code{OPEN} or @code{CREATE}.
755
756 @item OPEN @var{archive}
757 Opens an existing archive for use as the current archive (required for
758 many other commands). Any changes as the result of subsequent commands
759 will not actually affect @var{archive} until you next use @code{SAVE}.
760
761 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
762 In the current archive, replace each existing @var{module} (named in
763 the @code{REPLACE} arguments) from files in the current working directory.
764 To execute this command without errors, both the file, and the module in
765 the current archive, must exist.
766
767 Requires prior use of @code{OPEN} or @code{CREATE}.
768
769 @item VERBOSE
770 Toggle an internal flag governing the output from @code{DIRECTORY}.
771 When the flag is on, @code{DIRECTORY} output matches output from
772 @samp{ar -tv }@dots{}.
773
774 @item SAVE
775 Commit your changes to the current archive, and actually save it as a
776 file with the name specified in the last @code{CREATE} or @code{OPEN}
777 command.
778
779 Requires prior use of @code{OPEN} or @code{CREATE}.
780
781 @end table
782
783 @iftex
784 @node ld
785 @chapter ld
786 @cindex linker
787 @kindex ld
788 The @sc{gnu} linker @command{ld} is now described in a separate manual.
789 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
790 @end iftex
791
792 @node nm
793 @chapter nm
794 @cindex symbols
795 @kindex nm
796
797 @c man title nm list symbols from object files
798
799 @smallexample
800 @c man begin SYNOPSIS nm
801 nm [@option{-A}|@option{-o}|@option{--print-file-name}]
802 [@option{-a}|@option{--debug-syms}]
803 [@option{-B}|@option{--format=bsd}]
804 [@option{-C}|@option{--demangle}[=@var{style}]]
805 [@option{-D}|@option{--dynamic}]
806 [@option{-f}@var{format}|@option{--format=}@var{format}]
807 [@option{-g}|@option{--extern-only}]
808 [@option{-h}|@option{--help}]
809 [@option{--ifunc-chars=@var{CHARS}}]
810 [@option{-j}|@option{--format=just-symbols}]
811 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
812 [@option{-n}|@option{-v}|@option{--numeric-sort}]
813 [@option{-P}|@option{--portability}]
814 [@option{-p}|@option{--no-sort}]
815 [@option{-r}|@option{--reverse-sort}]
816 [@option{-S}|@option{--print-size}]
817 [@option{-s}|@option{--print-armap}]
818 [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
819 [@option{-u}|@option{--undefined-only}]
820 [@option{-U}|@option{--defined-only}]
821 [@option{-V}|@option{--version}]
822 [@option{-W}|@option{--no-weak}]
823 [@option{-X 32_64}]
824 [@option{--no-demangle}]
825 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
826 [@option{--plugin} @var{name}]
827 [@option{--size-sort}]
828 [@option{--special-syms}]
829 [@option{--synthetic}]
830 [@option{--target=}@var{bfdname}]
831 [@option{--unicode=}@var{method}]
832 [@option{--with-symbol-versions}]
833 [@option{--without-symbol-versions}]
834 [@var{objfile}@dots{}]
835 @c man end
836 @end smallexample
837
838 @c man begin DESCRIPTION nm
839 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
840 If no object files are listed as arguments, @command{nm} assumes the file
841 @file{a.out}.
842
843 For each symbol, @command{nm} shows:
844
845 @itemize @bullet
846 @item
847 The symbol value, in the radix selected by options (see below), or
848 hexadecimal by default.
849
850 @item
851 The symbol type. At least the following types are used; others are, as
852 well, depending on the object file format. If lowercase, the symbol is
853 usually local; if uppercase, the symbol is global (external). There
854 are however a few lowercase symbols that are shown for special global
855 symbols (@code{u}, @code{v} and @code{w}).
856
857 @c Some more detail on exactly what these symbol types are used for
858 @c would be nice.
859 @table @code
860 @item A
861 The symbol's value is absolute, and will not be changed by further
862 linking.
863
864 @item B
865 @itemx b
866 The symbol is in the BSS data section. This section typically
867 contains zero-initialized or uninitialized data, although the exact
868 behavior is system dependent.
869
870 @item C
871 @itemx c
872 The symbol is common. Common symbols are uninitialized data. When
873 linking, multiple common symbols may appear with the same name. If the
874 symbol is defined anywhere, the common symbols are treated as undefined
875 references.
876 @ifclear man
877 For more details on common symbols, see the discussion of
878 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
879 @end ifclear
880 The lower case @var{c} character is used when the symbol is in a
881 special section for small commons.
882
883 @item D
884 @itemx d
885 The symbol is in the initialized data section.
886
887 @item G
888 @itemx g
889 The symbol is in an initialized data section for small objects. Some
890 object file formats permit more efficient access to small data objects,
891 such as a global int variable as opposed to a large global array.
892
893 @item i
894 For PE format files this indicates that the symbol is in a section
895 specific to the implementation of DLLs.
896
897 For ELF format files this indicates that the symbol is an indirect
898 function. This is a GNU extension to the standard set of ELF symbol
899 types. It indicates a symbol which if referenced by a relocation does
900 not evaluate to its address, but instead must be invoked at runtime.
901 The runtime execution will then return the value to be used in the
902 relocation.
903
904 Note - the actual symbols display for GNU indirect symbols is
905 controlled by the @option{--ifunc-chars} command line option. If this
906 option has been provided then the first character in the string will
907 be used for global indirect function symbols. If the string contains
908 a second character then that will be used for local indirect function
909 symbols.
910
911 @item I
912 The symbol is an indirect reference to another symbol.
913
914 @item N
915 The symbol is a debugging symbol.
916
917 @item n
918 The symbol is in the read-only data section.
919
920 @item p
921 The symbol is in a stack unwind section.
922
923 @item R
924 @itemx r
925 The symbol is in a read only data section.
926
927 @item S
928 @itemx s
929 The symbol is in an uninitialized or zero-initialized data section
930 for small objects.
931
932 @item T
933 @itemx t
934 The symbol is in the text (code) section.
935
936 @item U
937 The symbol is undefined.
938
939 @item u
940 The symbol is a unique global symbol. This is a GNU extension to the
941 standard set of ELF symbol bindings. For such a symbol the dynamic linker
942 will make sure that in the entire process there is just one symbol with
943 this name and type in use.
944
945 @item V
946 @itemx v
947 The symbol is a weak object. When a weak defined symbol is linked with
948 a normal defined symbol, the normal defined symbol is used with no error.
949 When a weak undefined symbol is linked and the symbol is not defined,
950 the value of the weak symbol becomes zero with no error. On some
951 systems, uppercase indicates that a default value has been specified.
952
953 @item W
954 @itemx w
955 The symbol is a weak symbol that has not been specifically tagged as a
956 weak object symbol. When a weak defined symbol is linked with a normal
957 defined symbol, the normal defined symbol is used with no error.
958 When a weak undefined symbol is linked and the symbol is not defined,
959 the value of the symbol is determined in a system-specific manner without
960 error. On some systems, uppercase indicates that a default value has been
961 specified.
962
963 @item -
964 The symbol is a stabs symbol in an a.out object file. In this case, the
965 next values printed are the stabs other field, the stabs desc field, and
966 the stab type. Stabs symbols are used to hold debugging information.
967
968 @item ?
969 The symbol type is unknown, or object file format specific.
970 @end table
971
972 @item
973 The symbol name. If a symbol has version information associated with it,
974 then the version information is displayed as well. If the versioned
975 symbol is undefined or hidden from linker, the version string is displayed
976 as a suffix to the symbol name, preceded by an @@ character. For example
977 @samp{foo@@VER_1}. If the version is the default version to be used when
978 resolving unversioned references to the symbol, then it is displayed as a
979 suffix preceded by two @@ characters. For example @samp{foo@@@@VER_2}.
980 @end itemize
981
982 @c man end
983
984 @c man begin OPTIONS nm
985 The long and short forms of options, shown here as alternatives, are
986 equivalent.
987
988 @table @env
989 @item -A
990 @itemx -o
991 @itemx --print-file-name
992 @cindex input file name
993 @cindex file name
994 @cindex source file name
995 Precede each symbol by the name of the input file (or archive member)
996 in which it was found, rather than identifying the input file once only,
997 before all of its symbols.
998
999 @item -a
1000 @itemx --debug-syms
1001 @cindex debugging symbols
1002 Display all symbols, even debugger-only symbols; normally these are not
1003 listed.
1004
1005 @item -B
1006 @cindex @command{nm} format
1007 @cindex @command{nm} compatibility
1008 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
1009
1010 @item -C
1011 @itemx --demangle[=@var{style}]
1012 @cindex demangling in nm
1013 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1014 Besides removing any initial underscore prepended by the system, this
1015 makes C++ function names readable. Different compilers have different
1016 mangling styles. The optional demangling style argument can be used to
1017 choose an appropriate demangling style for your compiler. @xref{c++filt},
1018 for more information on demangling.
1019
1020 @item --no-demangle
1021 Do not demangle low-level symbol names. This is the default.
1022
1023 @item --recurse-limit
1024 @itemx --no-recurse-limit
1025 @itemx --recursion-limit
1026 @itemx --no-recursion-limit
1027 Enables or disables a limit on the amount of recursion performed
1028 whilst demangling strings. Since the name mangling formats allow for
1029 an infinite level of recursion it is possible to create strings whose
1030 decoding will exhaust the amount of stack space available on the host
1031 machine, triggering a memory fault. The limit tries to prevent this
1032 from happening by restricting recursion to 2048 levels of nesting.
1033
1034 The default is for this limit to be enabled, but disabling it may be
1035 necessary in order to demangle truly complicated names. Note however
1036 that if the recursion limit is disabled then stack exhaustion is
1037 possible and any bug reports about such an event will be rejected.
1038
1039 @item -D
1040 @itemx --dynamic
1041 @cindex dynamic symbols
1042 Display the dynamic symbols rather than the normal symbols. This is
1043 only meaningful for dynamic objects, such as certain types of shared
1044 libraries.
1045
1046 @item -f @var{format}
1047 @itemx --format=@var{format}
1048 @cindex @command{nm} format
1049 @cindex @command{nm} compatibility
1050 Use the output format @var{format}, which can be @code{bsd},
1051 @code{sysv}, @code{posix} or @code{just-symbols}. The default is @code{bsd}.
1052 Only the first character of @var{format} is significant; it can be
1053 either upper or lower case.
1054
1055 @item -g
1056 @itemx --extern-only
1057 @cindex external symbols
1058 Display only external symbols.
1059
1060 @item -h
1061 @itemx --help
1062 Show a summary of the options to @command{nm} and exit.
1063
1064 @item --ifunc-chars=@var{CHARS}
1065 When display GNU indirect function symbols @command{nm} will default
1066 to using the @code{i} character for both local indirect functions and
1067 global indirect functions. The @option{--ifunc-chars} option allows
1068 the user to specify a string containing one or two characters. The
1069 first character will be used for global indirect function symbols and
1070 the second character, if present, will be used for local indirect
1071 function symbols.
1072
1073 @item j
1074 The same as @option{--format=just-symbols}.
1075
1076 @item -l
1077 @itemx --line-numbers
1078 @cindex symbol line numbers
1079 For each symbol, use debugging information to try to find a filename and
1080 line number. For a defined symbol, look for the line number of the
1081 address of the symbol. For an undefined symbol, look for the line
1082 number of a relocation entry which refers to the symbol. If line number
1083 information can be found, print it after the other symbol information.
1084
1085 @item --inlines
1086 @cindex objdump inlines
1087 When option @option{-l} is active, if the address belongs to a
1088 function that was inlined, then this option causes the source
1089 information for all enclosing scopes back to the first non-inlined
1090 function to be printed as well. For example, if @code{main} inlines
1091 @code{callee1} which inlines @code{callee2}, and address is from
1092 @code{callee2}, the source information for @code{callee1} and @code{main}
1093 will also be printed.
1094
1095 @item -n
1096 @itemx -v
1097 @itemx --numeric-sort
1098 Sort symbols numerically by their addresses, rather than alphabetically
1099 by their names.
1100
1101 @item -p
1102 @itemx --no-sort
1103 @cindex sorting symbols
1104 Do not bother to sort the symbols in any order; print them in the order
1105 encountered.
1106
1107 @item -P
1108 @itemx --portability
1109 Use the POSIX.2 standard output format instead of the default format.
1110 Equivalent to @samp{-f posix}.
1111
1112 @item -r
1113 @itemx --reverse-sort
1114 Reverse the order of the sort (whether numeric or alphabetic); let the
1115 last come first.
1116
1117 @item -S
1118 @itemx --print-size
1119 Print both value and size of defined symbols for the @code{bsd} output style.
1120 This option has no effect for object formats that do not record symbol
1121 sizes, unless @samp{--size-sort} is also used in which case a
1122 calculated size is displayed.
1123
1124 @item -s
1125 @itemx --print-armap
1126 @cindex symbol index, listing
1127 When listing symbols from archive members, include the index: a mapping
1128 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1129 contain definitions for which names.
1130
1131 @item -t @var{radix}
1132 @itemx --radix=@var{radix}
1133 Use @var{radix} as the radix for printing the symbol values. It must be
1134 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1135
1136 @item -u
1137 @itemx --undefined-only
1138 @cindex external symbols
1139 @cindex undefined symbols
1140 Display only undefined symbols (those external to each object file).
1141 By default both defined and undefined symbols are displayed.
1142
1143 @item -U
1144 @itemx --defined-only
1145 @cindex external symbols
1146 @cindex undefined symbols
1147 Display only defined symbols for each object file.
1148 By default both defined and undefined symbols are displayed.
1149
1150 @item -V
1151 @itemx --version
1152 Show the version number of @command{nm} and exit.
1153
1154 @item -X
1155 This option is ignored for compatibility with the AIX version of
1156 @command{nm}. It takes one parameter which must be the string
1157 @option{32_64}. The default mode of AIX @command{nm} corresponds
1158 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1159
1160 @item --plugin @var{name}
1161 @cindex plugins
1162 Load the plugin called @var{name} to add support for extra target
1163 types. This option is only available if the toolchain has been built
1164 with plugin support enabled.
1165
1166 If @option{--plugin} is not provided, but plugin support has been
1167 enabled then @command{nm} iterates over the files in
1168 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1169 plugin that claims the object in question is used.
1170
1171 Please note that this plugin search directory is @emph{not} the one
1172 used by @command{ld}'s @option{-plugin} option. In order to make
1173 @command{nm} use the linker plugin it must be copied into the
1174 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1175 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1176 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1177 is always backwards compatible with earlier versions, so it is
1178 sufficient to just copy the newest one.
1179
1180 @item --size-sort
1181 Sort symbols by size. For ELF objects symbol sizes are read from the
1182 ELF, for other object types the symbol sizes are computed as the
1183 difference between the value of the symbol and the value of the symbol
1184 with the next higher value. If the @code{bsd} output format is used
1185 the size of the symbol is printed, rather than the value, and
1186 @samp{-S} must be used in order both size and value to be printed.
1187
1188 Note - this option does not work if @option{--undefined-only} has been
1189 enabled as undefined symbols have no size.
1190
1191 @item --special-syms
1192 Display symbols which have a target-specific special meaning. These
1193 symbols are usually used by the target for some special processing and
1194 are not normally helpful when included in the normal symbol lists.
1195 For example for ARM targets this option would skip the mapping symbols
1196 used to mark transitions between ARM code, THUMB code and data.
1197
1198 @item --synthetic
1199 Include synthetic symbols in the output. These are special symbols
1200 created by the linker for various purposes. They are not shown by
1201 default since they are not part of the binary's original source code.
1202
1203 @item --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
1204 Controls the display of UTF-8 encoded multibyte characters in strings.
1205 The default (@option{--unicode=default}) is to give them no special
1206 treatment. The @option{--unicode=locale} option displays the sequence
1207 in the current locale, which may or may not support them. The options
1208 @option{--unicode=hex} and @option{--unicode=invalid} display them as
1209 hex byte sequences enclosed by either angle brackets or curly braces.
1210
1211 The @option{--unicode=escape} option displays them as escape sequences
1212 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
1213 them as escape sequences highlighted in red (if supported by the
1214 output device). The colouring is intended to draw attention to the
1215 presence of unicode sequences where they might not be expected.
1216
1217 @item -W
1218 @itemx --no-weak
1219 Do not display weak symbols.
1220
1221 @item --with-symbol-versions
1222 @item --without-symbol-versions
1223 Enables or disables the display of symbol version information. The
1224 version string is displayed as a suffix to the symbol name, preceded
1225 by an @@ character. For example @samp{foo@@VER_1}. If the version is
1226 the default version to be used when resolving unversioned references
1227 to the symbol then it is displayed as a suffix preceded by two @@
1228 characters. For example @samp{foo@@@@VER_2}. By default, symbol
1229 version information is displayed.
1230
1231 @item --target=@var{bfdname}
1232 @cindex object code format
1233 Specify an object code format other than your system's default format.
1234 @xref{Target Selection}, for more information.
1235
1236 @end table
1237
1238 @c man end
1239
1240 @ignore
1241 @c man begin SEEALSO nm
1242 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1243 @c man end
1244 @end ignore
1245
1246 @node objcopy
1247 @chapter objcopy
1248
1249 @c man title objcopy copy and translate object files
1250
1251 @smallexample
1252 @c man begin SYNOPSIS objcopy
1253 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1254 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1255 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1256 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1257 [@option{-S}|@option{--strip-all}]
1258 [@option{-g}|@option{--strip-debug}]
1259 [@option{--strip-unneeded}]
1260 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1261 [@option{--keep-file-symbols}]
1262 [@option{--keep-section-symbols}]
1263 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1264 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1265 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1266 [@option{--localize-hidden}]
1267 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1268 [@option{--globalize-symbol=}@var{symbolname}]
1269 [@option{--globalize-symbols=}@var{filename}]
1270 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1271 [@option{-w}|@option{--wildcard}]
1272 [@option{-x}|@option{--discard-all}]
1273 [@option{-X}|@option{--discard-locals}]
1274 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1275 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1276 [@option{--interleave-width=}@var{width}]
1277 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1278 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1279 [@option{--keep-section=}@var{sectionpattern}]
1280 [@option{--remove-relocations=}@var{sectionpattern}]
1281 [@option{-p}|@option{--preserve-dates}]
1282 [@option{-D}|@option{--enable-deterministic-archives}]
1283 [@option{-U}|@option{--disable-deterministic-archives}]
1284 [@option{--debugging}]
1285 [@option{--gap-fill=}@var{val}]
1286 [@option{--pad-to=}@var{address}]
1287 [@option{--set-start=}@var{val}]
1288 [@option{--adjust-start=}@var{incr}]
1289 [@option{--change-addresses=}@var{incr}]
1290 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1291 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1292 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1293 [@option{--change-warnings}] [@option{--no-change-warnings}]
1294 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1295 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1296 [@option{--add-section} @var{sectionname}=@var{filename}]
1297 [@option{--dump-section} @var{sectionname}=@var{filename}]
1298 [@option{--update-section} @var{sectionname}=@var{filename}]
1299 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1300 [@option{--long-section-names} @{enable,disable,keep@}]
1301 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1302 [@option{--reverse-bytes=}@var{num}]
1303 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1304 [@option{--redefine-sym} @var{old}=@var{new}]
1305 [@option{--redefine-syms=}@var{filename}]
1306 [@option{--weaken}]
1307 [@option{--keep-symbols=}@var{filename}]
1308 [@option{--strip-symbols=}@var{filename}]
1309 [@option{--strip-unneeded-symbols=}@var{filename}]
1310 [@option{--keep-global-symbols=}@var{filename}]
1311 [@option{--localize-symbols=}@var{filename}]
1312 [@option{--weaken-symbols=}@var{filename}]
1313 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1314 [@option{--alt-machine-code=}@var{index}]
1315 [@option{--prefix-symbols=}@var{string}]
1316 [@option{--prefix-sections=}@var{string}]
1317 [@option{--prefix-alloc-sections=}@var{string}]
1318 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1319 [@option{--only-keep-debug}]
1320 [@option{--strip-dwo}]
1321 [@option{--extract-dwo}]
1322 [@option{--extract-symbol}]
1323 [@option{--writable-text}]
1324 [@option{--readonly-text}]
1325 [@option{--pure}]
1326 [@option{--impure}]
1327 [@option{--file-alignment=}@var{num}]
1328 [@option{--heap=}@var{size}]
1329 [@option{--image-base=}@var{address}]
1330 [@option{--section-alignment=}@var{num}]
1331 [@option{--stack=}@var{size}]
1332 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1333 [@option{--compress-debug-sections}]
1334 [@option{--decompress-debug-sections}]
1335 [@option{--elf-stt-common=@var{val}}]
1336 [@option{--merge-notes}]
1337 [@option{--no-merge-notes}]
1338 [@option{--verilog-data-width=@var{val}}]
1339 [@option{-v}|@option{--verbose}]
1340 [@option{-V}|@option{--version}]
1341 [@option{--help}] [@option{--info}]
1342 @var{infile} [@var{outfile}]
1343 @c man end
1344 @end smallexample
1345
1346 @c man begin DESCRIPTION objcopy
1347 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1348 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1349 read and write the object files. It can write the destination object
1350 file in a format different from that of the source object file. The
1351 exact behavior of @command{objcopy} is controlled by command-line options.
1352 Note that @command{objcopy} should be able to copy a fully linked file
1353 between any two formats. However, copying a relocatable object file
1354 between any two formats may not work as expected.
1355
1356 @command{objcopy} creates temporary files to do its translations and
1357 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1358 translation work; it has access to all the formats described in @sc{bfd}
1359 and thus is able to recognize most formats without being told
1360 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1361
1362 @command{objcopy} can be used to generate S-records by using an output
1363 target of @samp{srec} (e.g., use @samp{-O srec}).
1364
1365 @command{objcopy} can be used to generate a raw binary file by using an
1366 output target of @samp{binary} (e.g., use @option{-O binary}). When
1367 @command{objcopy} generates a raw binary file, it will essentially produce
1368 a memory dump of the contents of the input object file. All symbols and
1369 relocation information will be discarded. The memory dump will start at
1370 the load address of the lowest section copied into the output file.
1371
1372 When generating an S-record or a raw binary file, it may be helpful to
1373 use @option{-S} to remove sections containing debugging information. In
1374 some cases @option{-R} will be useful to remove sections which contain
1375 information that is not needed by the binary file.
1376
1377 Note---@command{objcopy} is not able to change the endianness of its input
1378 files. If the input format has an endianness (some formats do not),
1379 @command{objcopy} can only copy the inputs into file formats that have the
1380 same endianness or which have no endianness (e.g., @samp{srec}).
1381 (However, see the @option{--reverse-bytes} option.)
1382
1383 @c man end
1384
1385 @c man begin OPTIONS objcopy
1386
1387 @table @env
1388 @item @var{infile}
1389 @itemx @var{outfile}
1390 The input and output files, respectively.
1391 If you do not specify @var{outfile}, @command{objcopy} creates a
1392 temporary file and destructively renames the result with
1393 the name of @var{infile}.
1394
1395 @item -I @var{bfdname}
1396 @itemx --input-target=@var{bfdname}
1397 Consider the source file's object format to be @var{bfdname}, rather than
1398 attempting to deduce it. @xref{Target Selection}, for more information.
1399
1400 @item -O @var{bfdname}
1401 @itemx --output-target=@var{bfdname}
1402 Write the output file using the object format @var{bfdname}.
1403 @xref{Target Selection}, for more information.
1404
1405 @item -F @var{bfdname}
1406 @itemx --target=@var{bfdname}
1407 Use @var{bfdname} as the object format for both the input and the output
1408 file; i.e., simply transfer data from source to destination with no
1409 translation. @xref{Target Selection}, for more information.
1410
1411 @item -B @var{bfdarch}
1412 @itemx --binary-architecture=@var{bfdarch}
1413 Useful when transforming a architecture-less input file into an object file.
1414 In this case the output architecture can be set to @var{bfdarch}. This
1415 option will be ignored if the input file has a known @var{bfdarch}. You
1416 can access this binary data inside a program by referencing the special
1417 symbols that are created by the conversion process. These symbols are
1418 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1419 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1420 an object file and then access it in your code using these symbols.
1421
1422 @item -j @var{sectionpattern}
1423 @itemx --only-section=@var{sectionpattern}
1424 Copy only the indicated sections from the input file to the output file.
1425 This option may be given more than once. Note that using this option
1426 inappropriately may make the output file unusable. Wildcard
1427 characters are accepted in @var{sectionpattern}.
1428
1429 If the first character of @var{sectionpattern} is the exclamation
1430 point (!) then matching sections will not be copied, even if earlier
1431 use of @option{--only-section} on the same command line would
1432 otherwise copy it. For example:
1433
1434 @smallexample
1435 --only-section=.text.* --only-section=!.text.foo
1436 @end smallexample
1437
1438 will copy all sectinos matching '.text.*' but not the section
1439 '.text.foo'.
1440
1441 @item -R @var{sectionpattern}
1442 @itemx --remove-section=@var{sectionpattern}
1443 Remove any section matching @var{sectionpattern} from the output file.
1444 This option may be given more than once. Note that using this option
1445 inappropriately may make the output file unusable. Wildcard
1446 characters are accepted in @var{sectionpattern}. Using both the
1447 @option{-j} and @option{-R} options together results in undefined
1448 behaviour.
1449
1450 If the first character of @var{sectionpattern} is the exclamation
1451 point (!) then matching sections will not be removed even if an
1452 earlier use of @option{--remove-section} on the same command line
1453 would otherwise remove it. For example:
1454
1455 @smallexample
1456 --remove-section=.text.* --remove-section=!.text.foo
1457 @end smallexample
1458
1459 will remove all sections matching the pattern '.text.*', but will not
1460 remove the section '.text.foo'.
1461
1462 @item --keep-section=@var{sectionpattern}
1463 When removing sections from the output file, keep sections that match
1464 @var{sectionpattern}.
1465
1466 @item --remove-relocations=@var{sectionpattern}
1467 Remove non-dynamic relocations from the output file for any section
1468 matching @var{sectionpattern}. This option may be given more than
1469 once. Note that using this option inappropriately may make the output
1470 file unusable, and attempting to remove a dynamic relocation section
1471 such as @samp{.rela.plt} from an executable or shared library with
1472 @option{--remove-relocations=.plt} will not work. Wildcard characters
1473 are accepted in @var{sectionpattern}.
1474 For example:
1475
1476 @smallexample
1477 --remove-relocations=.text.*
1478 @end smallexample
1479
1480 will remove the relocations for all sections matching the pattern
1481 '.text.*'.
1482
1483 If the first character of @var{sectionpattern} is the exclamation
1484 point (!) then matching sections will not have their relocation
1485 removed even if an earlier use of @option{--remove-relocations} on the
1486 same command line would otherwise cause the relocations to be removed.
1487 For example:
1488
1489 @smallexample
1490 --remove-relocations=.text.* --remove-relocations=!.text.foo
1491 @end smallexample
1492
1493 will remove all relocations for sections matching the pattern
1494 '.text.*', but will not remove relocations for the section
1495 '.text.foo'.
1496
1497 @item -S
1498 @itemx --strip-all
1499 Do not copy relocation and symbol information from the source file.
1500 Also deletes debug sections.
1501
1502 @item -g
1503 @itemx --strip-debug
1504 Do not copy debugging symbols or sections from the source file.
1505
1506 @item --strip-unneeded
1507 Remove all symbols that are not needed for relocation processing in
1508 addition to debugging symbols and sections stripped by
1509 @option{--strip-debug}.
1510
1511 @item -K @var{symbolname}
1512 @itemx --keep-symbol=@var{symbolname}
1513 When stripping symbols, keep symbol @var{symbolname} even if it would
1514 normally be stripped. This option may be given more than once.
1515
1516 @item -N @var{symbolname}
1517 @itemx --strip-symbol=@var{symbolname}
1518 Do not copy symbol @var{symbolname} from the source file. This option
1519 may be given more than once.
1520
1521 @item --strip-unneeded-symbol=@var{symbolname}
1522 Do not copy symbol @var{symbolname} from the source file unless it is needed
1523 by a relocation. This option may be given more than once.
1524
1525 @item -G @var{symbolname}
1526 @itemx --keep-global-symbol=@var{symbolname}
1527 Keep only symbol @var{symbolname} global. Make all other symbols local
1528 to the file, so that they are not visible externally. This option may
1529 be given more than once. Note: this option cannot be used in
1530 conjunction with the @option{--globalize-symbol} or
1531 @option{--globalize-symbols} options.
1532
1533 @item --localize-hidden
1534 In an ELF object, mark all symbols that have hidden or internal visibility
1535 as local. This option applies on top of symbol-specific localization options
1536 such as @option{-L}.
1537
1538 @item -L @var{symbolname}
1539 @itemx --localize-symbol=@var{symbolname}
1540 Convert a global or weak symbol called @var{symbolname} into a local
1541 symbol, so that it is not visible externally. This option may be
1542 given more than once. Note - unique symbols are not converted.
1543
1544 @item -W @var{symbolname}
1545 @itemx --weaken-symbol=@var{symbolname}
1546 Make symbol @var{symbolname} weak. This option may be given more than once.
1547
1548 @item --globalize-symbol=@var{symbolname}
1549 Give symbol @var{symbolname} global scoping so that it is visible
1550 outside of the file in which it is defined. This option may be given
1551 more than once. Note: this option cannot be used in conjunction with
1552 the @option{-G} or @option{--keep-global-symbol} options.
1553
1554 @item -w
1555 @itemx --wildcard
1556 Permit regular expressions in @var{symbolname}s used in other command
1557 line options. The question mark (?), asterisk (*), backslash (\) and
1558 square brackets ([]) operators can be used anywhere in the symbol
1559 name. If the first character of the symbol name is the exclamation
1560 point (!) then the sense of the switch is reversed for that symbol.
1561 For example:
1562
1563 @smallexample
1564 -w -W !foo -W fo*
1565 @end smallexample
1566
1567 would cause objcopy to weaken all symbols that start with ``fo''
1568 except for the symbol ``foo''.
1569
1570 @item -x
1571 @itemx --discard-all
1572 Do not copy non-global symbols from the source file.
1573 @c FIXME any reason to prefer "non-global" to "local" here?
1574
1575 @item -X
1576 @itemx --discard-locals
1577 Do not copy compiler-generated local symbols.
1578 (These usually start with @samp{L} or @samp{.}.)
1579
1580 @item -b @var{byte}
1581 @itemx --byte=@var{byte}
1582 If interleaving has been enabled via the @option{--interleave} option
1583 then start the range of bytes to keep at the @var{byte}th byte.
1584 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1585 @var{breadth} is the value given by the @option{--interleave} option.
1586
1587 @item -i [@var{breadth}]
1588 @itemx --interleave[=@var{breadth}]
1589 Only copy a range out of every @var{breadth} bytes. (Header data is
1590 not affected). Select which byte in the range begins the copy with
1591 the @option{--byte} option. Select the width of the range with the
1592 @option{--interleave-width} option.
1593
1594 This option is useful for creating files to program @sc{rom}. It is
1595 typically used with an @code{srec} output target. Note that
1596 @command{objcopy} will complain if you do not specify the
1597 @option{--byte} option as well.
1598
1599 The default interleave breadth is 4, so with @option{--byte} set to 0,
1600 @command{objcopy} would copy the first byte out of every four bytes
1601 from the input to the output.
1602
1603 @item --interleave-width=@var{width}
1604 When used with the @option{--interleave} option, copy @var{width}
1605 bytes at a time. The start of the range of bytes to be copied is set
1606 by the @option{--byte} option, and the extent of the range is set with
1607 the @option{--interleave} option.
1608
1609 The default value for this option is 1. The value of @var{width} plus
1610 the @var{byte} value set by the @option{--byte} option must not exceed
1611 the interleave breadth set by the @option{--interleave} option.
1612
1613 This option can be used to create images for two 16-bit flashes interleaved
1614 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1615 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1616 commands. If the input was '12345678' then the outputs would be
1617 '1256' and '3478' respectively.
1618
1619 @item -p
1620 @itemx --preserve-dates
1621 Set the access and modification dates of the output file to be the same
1622 as those of the input file.
1623
1624 @item -D
1625 @itemx --enable-deterministic-archives
1626 @cindex deterministic archives
1627 @kindex --enable-deterministic-archives
1628 Operate in @emph{deterministic} mode. When copying archive members
1629 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1630 and use consistent file modes for all files.
1631
1632 If @file{binutils} was configured with
1633 @option{--enable-deterministic-archives}, then this mode is on by default.
1634 It can be disabled with the @samp{-U} option, below.
1635
1636 @item -U
1637 @itemx --disable-deterministic-archives
1638 @cindex deterministic archives
1639 @kindex --enable-deterministic-archives
1640 Do @emph{not} operate in @emph{deterministic} mode. This is the
1641 inverse of the @option{-D} option, above: when copying archive members
1642 and writing the archive index, use their actual UID, GID, timestamp,
1643 and file mode values.
1644
1645 This is the default unless @file{binutils} was configured with
1646 @option{--enable-deterministic-archives}.
1647
1648 @item --debugging
1649 Convert debugging information, if possible. This is not the default
1650 because only certain debugging formats are supported, and the
1651 conversion process can be time consuming.
1652
1653 @item --gap-fill @var{val}
1654 Fill gaps between sections with @var{val}. This operation applies to
1655 the @emph{load address} (LMA) of the sections. It is done by increasing
1656 the size of the section with the lower address, and filling in the extra
1657 space created with @var{val}.
1658
1659 @item --pad-to @var{address}
1660 Pad the output file up to the load address @var{address}. This is
1661 done by increasing the size of the last section. The extra space is
1662 filled in with the value specified by @option{--gap-fill} (default zero).
1663
1664 @item --set-start @var{val}
1665 Set the start address (also known as the entry address) of the new
1666 file to @var{val}. Not all object file formats support setting the
1667 start address.
1668
1669 @item --change-start @var{incr}
1670 @itemx --adjust-start @var{incr}
1671 @cindex changing start address
1672 Change the start address (also known as the entry address) by adding
1673 @var{incr}. Not all object file formats support setting the start
1674 address.
1675
1676 @item --change-addresses @var{incr}
1677 @itemx --adjust-vma @var{incr}
1678 @cindex changing object addresses
1679 Change the VMA and LMA addresses of all sections, as well as the start
1680 address, by adding @var{incr}. Some object file formats do not permit
1681 section addresses to be changed arbitrarily. Note that this does not
1682 relocate the sections; if the program expects sections to be loaded at a
1683 certain address, and this option is used to change the sections such
1684 that they are loaded at a different address, the program may fail.
1685
1686 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1687 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1688 @cindex changing section address
1689 Set or change both the VMA address and the LMA address of any section
1690 matching @var{sectionpattern}. If @samp{=} is used, the section
1691 address is set to @var{val}. Otherwise, @var{val} is added to or
1692 subtracted from the section address. See the comments under
1693 @option{--change-addresses}, above. If @var{sectionpattern} does not
1694 match any sections in the input file, a warning will be issued, unless
1695 @option{--no-change-warnings} is used.
1696
1697 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1698 @cindex changing section LMA
1699 Set or change the LMA address of any sections matching
1700 @var{sectionpattern}. The LMA address is the address where the
1701 section will be loaded into memory at program load time. Normally
1702 this is the same as the VMA address, which is the address of the
1703 section at program run time, but on some systems, especially those
1704 where a program is held in ROM, the two can be different. If @samp{=}
1705 is used, the section address is set to @var{val}. Otherwise,
1706 @var{val} is added to or subtracted from the section address. See the
1707 comments under @option{--change-addresses}, above. If
1708 @var{sectionpattern} does not match any sections in the input file, a
1709 warning will be issued, unless @option{--no-change-warnings} is used.
1710
1711 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1712 @cindex changing section VMA
1713 Set or change the VMA address of any section matching
1714 @var{sectionpattern}. The VMA address is the address where the
1715 section will be located once the program has started executing.
1716 Normally this is the same as the LMA address, which is the address
1717 where the section will be loaded into memory, but on some systems,
1718 especially those where a program is held in ROM, the two can be
1719 different. If @samp{=} is used, the section address is set to
1720 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1721 section address. See the comments under @option{--change-addresses},
1722 above. If @var{sectionpattern} does not match any sections in the
1723 input file, a warning will be issued, unless
1724 @option{--no-change-warnings} is used.
1725
1726 @item --change-warnings
1727 @itemx --adjust-warnings
1728 If @option{--change-section-address} or @option{--change-section-lma} or
1729 @option{--change-section-vma} is used, and the section pattern does not
1730 match any sections, issue a warning. This is the default.
1731
1732 @item --no-change-warnings
1733 @itemx --no-adjust-warnings
1734 Do not issue a warning if @option{--change-section-address} or
1735 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1736 if the section pattern does not match any sections.
1737
1738 @item --set-section-flags @var{sectionpattern}=@var{flags}
1739 Set the flags for any sections matching @var{sectionpattern}. The
1740 @var{flags} argument is a comma separated string of flag names. The
1741 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1742 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1743 @samp{exclude}, @samp{share}, and @samp{debug}. You can set the
1744 @samp{contents} flag for a section which does not have contents, but it
1745 is not meaningful to clear the @samp{contents} flag of a section which
1746 does have contents--just remove the section instead. Not all flags are
1747 meaningful for all object file formats. In particular the
1748 @samp{share} flag is only meaningful for COFF format files and not for
1749 ELF format files.
1750
1751 @item --set-section-alignment @var{sectionpattern}=@var{align}
1752 Set the alignment for any sections matching @var{sectionpattern}.
1753 @var{align} specifies the alignment in bytes and must be a power of
1754 two, i.e. 1, 2, 4, 8@dots{}.
1755
1756 @item --add-section @var{sectionname}=@var{filename}
1757 Add a new section named @var{sectionname} while copying the file. The
1758 contents of the new section are taken from the file @var{filename}. The
1759 size of the section will be the size of the file. This option only
1760 works on file formats which can support sections with arbitrary names.
1761 Note - it may be necessary to use the @option{--set-section-flags}
1762 option to set the attributes of the newly created section.
1763
1764 @item --dump-section @var{sectionname}=@var{filename}
1765 Place the contents of section named @var{sectionname} into the file
1766 @var{filename}, overwriting any contents that may have been there
1767 previously. This option is the inverse of @option{--add-section}.
1768 This option is similar to the @option{--only-section} option except
1769 that it does not create a formatted file, it just dumps the contents
1770 as raw binary data, without applying any relocations. The option can
1771 be specified more than once.
1772
1773 @item --update-section @var{sectionname}=@var{filename}
1774 Replace the existing contents of a section named @var{sectionname}
1775 with the contents of file @var{filename}. The size of the section
1776 will be adjusted to the size of the file. The section flags for
1777 @var{sectionname} will be unchanged. For ELF format files the section
1778 to segment mapping will also remain unchanged, something which is not
1779 possible using @option{--remove-section} followed by
1780 @option{--add-section}. The option can be specified more than once.
1781
1782 Note - it is possible to use @option{--rename-section} and
1783 @option{--update-section} to both update and rename a section from one
1784 command line. In this case, pass the original section name to
1785 @option{--update-section}, and the original and new section names to
1786 @option{--rename-section}.
1787
1788 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1789 Add a new symbol named @var{name} while copying the file. This option may be
1790 specified multiple times. If the @var{section} is given, the symbol will be
1791 associated with and relative to that section, otherwise it will be an ABS
1792 symbol. Specifying an undefined section will result in a fatal error. There
1793 is no check for the value, it will be taken as specified. Symbol flags can
1794 be specified and not all flags will be meaningful for all object file
1795 formats. By default, the symbol will be global. The special flag
1796 'before=@var{othersym}' will insert the new symbol in front of the specified
1797 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1798 symbol table in the order they appear.
1799
1800 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1801 Rename a section from @var{oldname} to @var{newname}, optionally
1802 changing the section's flags to @var{flags} in the process. This has
1803 the advantage over using a linker script to perform the rename in that
1804 the output stays as an object file and does not become a linked
1805 executable. This option accepts the same set of flags as the
1806 @option{--sect-section-flags} option.
1807
1808 This option is particularly helpful when the input format is binary,
1809 since this will always create a section called .data. If for example,
1810 you wanted instead to create a section called .rodata containing binary
1811 data you could use the following command line to achieve it:
1812
1813 @smallexample
1814 objcopy -I binary -O <output_format> -B <architecture> \
1815 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1816 <input_binary_file> <output_object_file>
1817 @end smallexample
1818
1819 @item --long-section-names @{enable,disable,keep@}
1820 Controls the handling of long section names when processing @code{COFF}
1821 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1822 is to preserve long section names if any are present in the input file.
1823 The @samp{enable} and @samp{disable} options forcibly enable or disable
1824 the use of long section names in the output object; when @samp{disable}
1825 is in effect, any long section names in the input object will be truncated.
1826 The @samp{enable} option will only emit long section names if any are
1827 present in the inputs; this is mostly the same as @samp{keep}, but it
1828 is left undefined whether the @samp{enable} option might force the
1829 creation of an empty string table in the output file.
1830
1831 @item --change-leading-char
1832 Some object file formats use special characters at the start of
1833 symbols. The most common such character is underscore, which compilers
1834 often add before every symbol. This option tells @command{objcopy} to
1835 change the leading character of every symbol when it converts between
1836 object file formats. If the object file formats use the same leading
1837 character, this option has no effect. Otherwise, it will add a
1838 character, or remove a character, or change a character, as
1839 appropriate.
1840
1841 @item --remove-leading-char
1842 If the first character of a global symbol is a special symbol leading
1843 character used by the object file format, remove the character. The
1844 most common symbol leading character is underscore. This option will
1845 remove a leading underscore from all global symbols. This can be useful
1846 if you want to link together objects of different file formats with
1847 different conventions for symbol names. This is different from
1848 @option{--change-leading-char} because it always changes the symbol name
1849 when appropriate, regardless of the object file format of the output
1850 file.
1851
1852 @item --reverse-bytes=@var{num}
1853 Reverse the bytes in a section with output contents. A section length must
1854 be evenly divisible by the value given in order for the swap to be able to
1855 take place. Reversing takes place before the interleaving is performed.
1856
1857 This option is used typically in generating ROM images for problematic
1858 target systems. For example, on some target boards, the 32-bit words
1859 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1860 regardless of the CPU byte order. Depending on the programming model, the
1861 endianness of the ROM may need to be modified.
1862
1863 Consider a simple file with a section containing the following eight
1864 bytes: @code{12345678}.
1865
1866 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1867 output file would be ordered @code{21436587}.
1868
1869 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1870 output file would be ordered @code{43218765}.
1871
1872 By using @samp{--reverse-bytes=2} for the above example, followed by
1873 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1874 output file would be ordered @code{34127856}.
1875
1876 @item --srec-len=@var{ival}
1877 Meaningful only for srec output. Set the maximum length of the Srecords
1878 being produced to @var{ival}. This length covers both address, data and
1879 crc fields.
1880
1881 @item --srec-forceS3
1882 Meaningful only for srec output. Avoid generation of S1/S2 records,
1883 creating S3-only record format.
1884
1885 @item --redefine-sym @var{old}=@var{new}
1886 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1887 when one is trying link two things together for which you have no
1888 source, and there are name collisions.
1889
1890 @item --redefine-syms=@var{filename}
1891 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1892 listed in the file @var{filename}. @var{filename} is simply a flat file,
1893 with one symbol pair per line. Line comments may be introduced by the hash
1894 character. This option may be given more than once.
1895
1896 @item --weaken
1897 Change all global symbols in the file to be weak. This can be useful
1898 when building an object which will be linked against other objects using
1899 the @option{-R} option to the linker. This option is only effective when
1900 using an object file format which supports weak symbols.
1901
1902 @item --keep-symbols=@var{filename}
1903 Apply @option{--keep-symbol} option to each symbol listed in the file
1904 @var{filename}. @var{filename} is simply a flat file, with one symbol
1905 name per line. Line comments may be introduced by the hash character.
1906 This option may be given more than once.
1907
1908 @item --strip-symbols=@var{filename}
1909 Apply @option{--strip-symbol} option to each symbol listed in the file
1910 @var{filename}. @var{filename} is simply a flat file, with one symbol
1911 name per line. Line comments may be introduced by the hash character.
1912 This option may be given more than once.
1913
1914 @item --strip-unneeded-symbols=@var{filename}
1915 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1916 the file @var{filename}. @var{filename} is simply a flat file, with one
1917 symbol name per line. Line comments may be introduced by the hash
1918 character. This option may be given more than once.
1919
1920 @item --keep-global-symbols=@var{filename}
1921 Apply @option{--keep-global-symbol} option to each symbol listed in the
1922 file @var{filename}. @var{filename} is simply a flat file, with one
1923 symbol name per line. Line comments may be introduced by the hash
1924 character. This option may be given more than once.
1925
1926 @item --localize-symbols=@var{filename}
1927 Apply @option{--localize-symbol} option to each symbol listed in the file
1928 @var{filename}. @var{filename} is simply a flat file, with one symbol
1929 name per line. Line comments may be introduced by the hash character.
1930 This option may be given more than once.
1931
1932 @item --globalize-symbols=@var{filename}
1933 Apply @option{--globalize-symbol} option to each symbol listed in the file
1934 @var{filename}. @var{filename} is simply a flat file, with one symbol
1935 name per line. Line comments may be introduced by the hash character.
1936 This option may be given more than once. Note: this option cannot be
1937 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1938 options.
1939
1940 @item --weaken-symbols=@var{filename}
1941 Apply @option{--weaken-symbol} option to each symbol listed in the file
1942 @var{filename}. @var{filename} is simply a flat file, with one symbol
1943 name per line. Line comments may be introduced by the hash character.
1944 This option may be given more than once.
1945
1946 @item --alt-machine-code=@var{index}
1947 If the output architecture has alternate machine codes, use the
1948 @var{index}th code instead of the default one. This is useful in case
1949 a machine is assigned an official code and the tool-chain adopts the
1950 new code, but other applications still depend on the original code
1951 being used. For ELF based architectures if the @var{index}
1952 alternative does not exist then the value is treated as an absolute
1953 number to be stored in the e_machine field of the ELF header.
1954
1955 @item --writable-text
1956 Mark the output text as writable. This option isn't meaningful for all
1957 object file formats.
1958
1959 @item --readonly-text
1960 Make the output text write protected. This option isn't meaningful for all
1961 object file formats.
1962
1963 @item --pure
1964 Mark the output file as demand paged. This option isn't meaningful for all
1965 object file formats.
1966
1967 @item --impure
1968 Mark the output file as impure. This option isn't meaningful for all
1969 object file formats.
1970
1971 @item --prefix-symbols=@var{string}
1972 Prefix all symbols in the output file with @var{string}.
1973
1974 @item --prefix-sections=@var{string}
1975 Prefix all section names in the output file with @var{string}.
1976
1977 @item --prefix-alloc-sections=@var{string}
1978 Prefix all the names of all allocated sections in the output file with
1979 @var{string}.
1980
1981 @item --add-gnu-debuglink=@var{path-to-file}
1982 Creates a .gnu_debuglink section which contains a reference to
1983 @var{path-to-file} and adds it to the output file. Note: the file at
1984 @var{path-to-file} must exist. Part of the process of adding the
1985 .gnu_debuglink section involves embedding a checksum of the contents
1986 of the debug info file into the section.
1987
1988 If the debug info file is built in one location but it is going to be
1989 installed at a later time into a different location then do not use
1990 the path to the installed location. The @option{--add-gnu-debuglink}
1991 option will fail because the installed file does not exist yet.
1992 Instead put the debug info file in the current directory and use the
1993 @option{--add-gnu-debuglink} option without any directory components,
1994 like this:
1995
1996 @smallexample
1997 objcopy --add-gnu-debuglink=foo.debug
1998 @end smallexample
1999
2000 At debug time the debugger will attempt to look for the separate debug
2001 info file in a set of known locations. The exact set of these
2002 locations varies depending upon the distribution being used, but it
2003 typically includes:
2004
2005 @table @code
2006
2007 @item * The same directory as the executable.
2008
2009 @item * A sub-directory of the directory containing the executable
2010 called .debug
2011
2012 @item * A global debug directory such as /usr/lib/debug.
2013 @end table
2014
2015 As long as the debug info file has been installed into one of these
2016 locations before the debugger is run everything should work
2017 correctly.
2018
2019 @item --keep-section-symbils
2020 When stripping a file, perhaps with @option{--strip-debug} or
2021 @option{--strip-unneeded}, retain any symbols specifying section names,
2022 which would otherwise get stripped.
2023
2024 @item --keep-file-symbols
2025 When stripping a file, perhaps with @option{--strip-debug} or
2026 @option{--strip-unneeded}, retain any symbols specifying source file names,
2027 which would otherwise get stripped.
2028
2029 @item --only-keep-debug
2030 Strip a file, removing contents of any sections that would not be
2031 stripped by @option{--strip-debug} and leaving the debugging sections
2032 intact. In ELF files, this preserves all note sections in the output.
2033
2034 Note - the section headers of the stripped sections are preserved,
2035 including their sizes, but the contents of the section are discarded.
2036 The section headers are preserved so that other tools can match up the
2037 debuginfo file with the real executable, even if that executable has
2038 been relocated to a different address space.
2039
2040 The intention is that this option will be used in conjunction with
2041 @option{--add-gnu-debuglink} to create a two part executable. One a
2042 stripped binary which will occupy less space in RAM and in a
2043 distribution and the second a debugging information file which is only
2044 needed if debugging abilities are required. The suggested procedure
2045 to create these files is as follows:
2046
2047 @enumerate
2048 @item Link the executable as normal. Assuming that it is called
2049 @code{foo} then...
2050 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2051 create a file containing the debugging info.
2052 @item Run @code{objcopy --strip-debug foo} to create a
2053 stripped executable.
2054 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2055 to add a link to the debugging info into the stripped executable.
2056 @end enumerate
2057
2058 Note---the choice of @code{.dbg} as an extension for the debug info
2059 file is arbitrary. Also the @code{--only-keep-debug} step is
2060 optional. You could instead do this:
2061
2062 @enumerate
2063 @item Link the executable as normal.
2064 @item Copy @code{foo} to @code{foo.full}
2065 @item Run @code{objcopy --strip-debug foo}
2066 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2067 @end enumerate
2068
2069 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2070 full executable. It does not have to be a file created by the
2071 @option{--only-keep-debug} switch.
2072
2073 Note---this switch is only intended for use on fully linked files. It
2074 does not make sense to use it on object files where the debugging
2075 information may be incomplete. Besides the gnu_debuglink feature
2076 currently only supports the presence of one filename containing
2077 debugging information, not multiple filenames on a one-per-object-file
2078 basis.
2079
2080 @item --strip-dwo
2081 Remove the contents of all DWARF .dwo sections, leaving the
2082 remaining debugging sections and all symbols intact.
2083 This option is intended for use by the compiler as part of
2084 the @option{-gsplit-dwarf} option, which splits debug information
2085 between the .o file and a separate .dwo file. The compiler
2086 generates all debug information in the same file, then uses
2087 the @option{--extract-dwo} option to copy the .dwo sections to
2088 the .dwo file, then the @option{--strip-dwo} option to remove
2089 those sections from the original .o file.
2090
2091 @item --extract-dwo
2092 Extract the contents of all DWARF .dwo sections. See the
2093 @option{--strip-dwo} option for more information.
2094
2095 @item --file-alignment @var{num}
2096 Specify the file alignment. Sections in the file will always begin at
2097 file offsets which are multiples of this number. This defaults to
2098 512.
2099 [This option is specific to PE targets.]
2100
2101 @item --heap @var{reserve}
2102 @itemx --heap @var{reserve},@var{commit}
2103 Specify the number of bytes of memory to reserve (and optionally commit)
2104 to be used as heap for this program.
2105 [This option is specific to PE targets.]
2106
2107 @item --image-base @var{value}
2108 Use @var{value} as the base address of your program or dll. This is
2109 the lowest memory location that will be used when your program or dll
2110 is loaded. To reduce the need to relocate and improve performance of
2111 your dlls, each should have a unique base address and not overlap any
2112 other dlls. The default is 0x400000 for executables, and 0x10000000
2113 for dlls.
2114 [This option is specific to PE targets.]
2115
2116 @item --section-alignment @var{num}
2117 Sets the section alignment field in the PE header. Sections in memory
2118 will always begin at addresses which are a multiple of this number.
2119 Defaults to 0x1000.
2120 [This option is specific to PE targets.]
2121
2122 @item --stack @var{reserve}
2123 @itemx --stack @var{reserve},@var{commit}
2124 Specify the number of bytes of memory to reserve (and optionally commit)
2125 to be used as stack for this program.
2126 [This option is specific to PE targets.]
2127
2128 @item --subsystem @var{which}
2129 @itemx --subsystem @var{which}:@var{major}
2130 @itemx --subsystem @var{which}:@var{major}.@var{minor}
2131 Specifies the subsystem under which your program will execute. The
2132 legal values for @var{which} are @code{native}, @code{windows},
2133 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2134 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2135 the subsystem version also. Numeric values are also accepted for
2136 @var{which}.
2137 [This option is specific to PE targets.]
2138
2139 @item --extract-symbol
2140 Keep the file's section flags and symbols but remove all section data.
2141 Specifically, the option:
2142
2143 @itemize
2144 @item removes the contents of all sections;
2145 @item sets the size of every section to zero; and
2146 @item sets the file's start address to zero.
2147 @end itemize
2148
2149 This option is used to build a @file{.sym} file for a VxWorks kernel.
2150 It can also be a useful way of reducing the size of a @option{--just-symbols}
2151 linker input file.
2152
2153 @item --compress-debug-sections
2154 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2155 ELF ABI. Note - if compression would actually make a section
2156 @emph{larger}, then it is not compressed.
2157
2158 @item --compress-debug-sections=none
2159 @itemx --compress-debug-sections=zlib
2160 @itemx --compress-debug-sections=zlib-gnu
2161 @itemx --compress-debug-sections=zlib-gabi
2162 For ELF files, these options control how DWARF debug sections are
2163 compressed. @option{--compress-debug-sections=none} is equivalent
2164 to @option{--decompress-debug-sections}.
2165 @option{--compress-debug-sections=zlib} and
2166 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2167 @option{--compress-debug-sections}.
2168 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
2169 sections using zlib. The debug sections are renamed to begin with
2170 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
2171 actually make a section @emph{larger}, then it is not compressed nor
2172 renamed.
2173
2174 @item --decompress-debug-sections
2175 Decompress DWARF debug sections using zlib. The original section
2176 names of the compressed sections are restored.
2177
2178 @item --elf-stt-common=yes
2179 @itemx --elf-stt-common=no
2180 For ELF files, these options control whether common symbols should be
2181 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2182 @option{--elf-stt-common=yes} converts common symbol type to
2183 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2184 type to @code{STT_OBJECT}.
2185
2186 @item --merge-notes
2187 @itemx --no-merge-notes
2188 For ELF files, attempt (or do not attempt) to reduce the size of any
2189 SHT_NOTE type sections by removing duplicate notes.
2190
2191 @item -V
2192 @itemx --version
2193 Show the version number of @command{objcopy}.
2194
2195 @item --verilog-data-width=@var{bytes}
2196 For Verilog output, this options controls the number of bytes
2197 converted for each output data element. The input target controls the
2198 endianness of the conversion.
2199
2200 @item -v
2201 @itemx --verbose
2202 Verbose output: list all object files modified. In the case of
2203 archives, @samp{objcopy -V} lists all members of the archive.
2204
2205 @item --help
2206 Show a summary of the options to @command{objcopy}.
2207
2208 @item --info
2209 Display a list showing all architectures and object formats available.
2210 @end table
2211
2212 @c man end
2213
2214 @ignore
2215 @c man begin SEEALSO objcopy
2216 ld(1), objdump(1), and the Info entries for @file{binutils}.
2217 @c man end
2218 @end ignore
2219
2220 @node objdump
2221 @chapter objdump
2222
2223 @cindex object file information
2224 @kindex objdump
2225
2226 @c man title objdump display information from object files
2227
2228 @smallexample
2229 @c man begin SYNOPSIS objdump
2230 objdump [@option{-a}|@option{--archive-headers}]
2231 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2232 [@option{-C}|@option{--demangle}[=@var{style}] ]
2233 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2234 [@option{-D}|@option{--disassemble-all}]
2235 [@option{-z}|@option{--disassemble-zeroes}]
2236 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2237 [@option{-f}|@option{--file-headers}]
2238 [@option{-F}|@option{--file-offsets}]
2239 [@option{--file-start-context}]
2240 [@option{-g}|@option{--debugging}]
2241 [@option{-e}|@option{--debugging-tags}]
2242 [@option{-h}|@option{--section-headers}|@option{--headers}]
2243 [@option{-i}|@option{--info}]
2244 [@option{-j} @var{section}|@option{--section=}@var{section}]
2245 [@option{-l}|@option{--line-numbers}]
2246 [@option{-S}|@option{--source}]
2247 [@option{--source-comment}[=@var{text}]]
2248 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2249 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2250 [@option{-p}|@option{--private-headers}]
2251 [@option{-P} @var{options}|@option{--private=}@var{options}]
2252 [@option{-r}|@option{--reloc}]
2253 [@option{-R}|@option{--dynamic-reloc}]
2254 [@option{-s}|@option{--full-contents}]
2255 [@option{-W[lLiaprmfFsoORtUuTgAck]}|
2256 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
2257 [@option{-WK}|@option{--dwarf=follow-links}]
2258 [@option{-WN}|@option{--dwarf=no-follow-links}]
2259 [@option{-wD}|@option{--dwarf=use-debuginfod}]
2260 [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
2261 [@option{-L}|@option{--process-links}]
2262 [@option{--ctf=}@var{section}]
2263 [@option{-G}|@option{--stabs}]
2264 [@option{-t}|@option{--syms}]
2265 [@option{-T}|@option{--dynamic-syms}]
2266 [@option{-x}|@option{--all-headers}]
2267 [@option{-w}|@option{--wide}]
2268 [@option{--start-address=}@var{address}]
2269 [@option{--stop-address=}@var{address}]
2270 [@option{--no-addresses}]
2271 [@option{--prefix-addresses}]
2272 [@option{--[no-]show-raw-insn}]
2273 [@option{--adjust-vma=}@var{offset}]
2274 [@option{--dwarf-depth=@var{n}}]
2275 [@option{--dwarf-start=@var{n}}]
2276 [@option{--ctf-parent=}@var{section}]
2277 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2278 [@option{--special-syms}]
2279 [@option{--prefix=}@var{prefix}]
2280 [@option{--prefix-strip=}@var{level}]
2281 [@option{--insn-width=}@var{width}]
2282 [@option{--visualize-jumps[=color|=extended-color|=off]}
2283 [@option{--disassembler-color=[color|extended-color|off]}
2284 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
2285 [@option{-V}|@option{--version}]
2286 [@option{-H}|@option{--help}]
2287 @var{objfile}@dots{}
2288 @c man end
2289 @end smallexample
2290
2291 @c man begin DESCRIPTION objdump
2292
2293 @command{objdump} displays information about one or more object files.
2294 The options control what particular information to display. This
2295 information is mostly useful to programmers who are working on the
2296 compilation tools, as opposed to programmers who just want their
2297 program to compile and work.
2298
2299 @var{objfile}@dots{} are the object files to be examined. When you
2300 specify archives, @command{objdump} shows information on each of the member
2301 object files.
2302
2303 @c man end
2304
2305 @c man begin OPTIONS objdump
2306
2307 The long and short forms of options, shown here as alternatives, are
2308 equivalent. At least one option from the list
2309 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2310
2311 @table @env
2312 @item -a
2313 @itemx --archive-header
2314 @cindex archive headers
2315 If any of the @var{objfile} files are archives, display the archive
2316 header information (in a format similar to @samp{ls -l}). Besides the
2317 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2318 the object file format of each archive member.
2319
2320 @item --adjust-vma=@var{offset}
2321 @cindex section addresses in objdump
2322 @cindex VMA in objdump
2323 When dumping information, first add @var{offset} to all the section
2324 addresses. This is useful if the section addresses do not correspond to
2325 the symbol table, which can happen when putting sections at particular
2326 addresses when using a format which can not represent section addresses,
2327 such as a.out.
2328
2329 @item -b @var{bfdname}
2330 @itemx --target=@var{bfdname}
2331 @cindex object code format
2332 Specify that the object-code format for the object files is
2333 @var{bfdname}. This option may not be necessary; @var{objdump} can
2334 automatically recognize many formats.
2335
2336 For example,
2337 @example
2338 objdump -b oasys -m vax -h fu.o
2339 @end example
2340 @noindent
2341 displays summary information from the section headers (@option{-h}) of
2342 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2343 file in the format produced by Oasys compilers. You can list the
2344 formats available with the @option{-i} option.
2345 @xref{Target Selection}, for more information.
2346
2347 @item -C
2348 @itemx --demangle[=@var{style}]
2349 @cindex demangling in objdump
2350 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2351 Besides removing any initial underscore prepended by the system, this
2352 makes C++ function names readable. Different compilers have different
2353 mangling styles. The optional demangling style argument can be used to
2354 choose an appropriate demangling style for your compiler. @xref{c++filt},
2355 for more information on demangling.
2356
2357 @item --recurse-limit
2358 @itemx --no-recurse-limit
2359 @itemx --recursion-limit
2360 @itemx --no-recursion-limit
2361 Enables or disables a limit on the amount of recursion performed
2362 whilst demangling strings. Since the name mangling formats allow for
2363 an infinite level of recursion it is possible to create strings whose
2364 decoding will exhaust the amount of stack space available on the host
2365 machine, triggering a memory fault. The limit tries to prevent this
2366 from happening by restricting recursion to 2048 levels of nesting.
2367
2368 The default is for this limit to be enabled, but disabling it may be
2369 necessary in order to demangle truly complicated names. Note however
2370 that if the recursion limit is disabled then stack exhaustion is
2371 possible and any bug reports about such an event will be rejected.
2372
2373 @item -g
2374 @itemx --debugging
2375 Display debugging information. This attempts to parse STABS
2376 debugging format information stored in the file and print it out using
2377 a C like syntax. If no STABS debugging was found this option
2378 falls back on the @option{-W} option to print any DWARF information in
2379 the file.
2380
2381 @item -e
2382 @itemx --debugging-tags
2383 Like @option{-g}, but the information is generated in a format compatible
2384 with ctags tool.
2385
2386 @item -d
2387 @itemx --disassemble
2388 @itemx --disassemble=@var{symbol}
2389 @cindex disassembling object code
2390 @cindex machine instructions
2391 Display the assembler mnemonics for the machine instructions from the
2392 input file. This option only disassembles those sections which are
2393 expected to contain instructions. If the optional @var{symbol}
2394 argument is given, then display the assembler mnemonics starting at
2395 @var{symbol}. If @var{symbol} is a function name then disassembly
2396 will stop at the end of the function, otherwise it will stop when the
2397 next symbol is encountered. If there are no matches for @var{symbol}
2398 then nothing will be displayed.
2399
2400 Note if the @option{--dwarf=follow-links} option is enabled
2401 then any symbol tables in linked debug info files will be read in and
2402 used when disassembling.
2403
2404 @item -D
2405 @itemx --disassemble-all
2406 Like @option{-d}, but disassemble the contents of all sections, not just
2407 those expected to contain instructions.
2408
2409 This option also has a subtle effect on the disassembly of
2410 instructions in code sections. When option @option{-d} is in effect
2411 objdump will assume that any symbols present in a code section occur
2412 on the boundary between instructions and it will refuse to disassemble
2413 across such a boundary. When option @option{-D} is in effect however
2414 this assumption is supressed. This means that it is possible for the
2415 output of @option{-d} and @option{-D} to differ if, for example, data
2416 is stored in code sections.
2417
2418 If the target is an ARM architecture this switch also has the effect
2419 of forcing the disassembler to decode pieces of data found in code
2420 sections as if they were instructions.
2421
2422 Note if the @option{--dwarf=follow-links} option is enabled
2423 then any symbol tables in linked debug info files will be read in and
2424 used when disassembling.
2425
2426 @item --no-addresses
2427 When disassembling, don't print addresses on each line or for symbols
2428 and relocation offsets. In combination with @option{--no-show-raw-insn}
2429 this may be useful for comparing compiler output.
2430
2431 @item --prefix-addresses
2432 When disassembling, print the complete address on each line. This is
2433 the older disassembly format.
2434
2435 @item -EB
2436 @itemx -EL
2437 @itemx --endian=@{big|little@}
2438 @cindex endianness
2439 @cindex disassembly endianness
2440 Specify the endianness of the object files. This only affects
2441 disassembly. This can be useful when disassembling a file format which
2442 does not describe endianness information, such as S-records.
2443
2444 @item -f
2445 @itemx --file-headers
2446 @cindex object file header
2447 Display summary information from the overall header of
2448 each of the @var{objfile} files.
2449
2450 @item -F
2451 @itemx --file-offsets
2452 @cindex object file offsets
2453 When disassembling sections, whenever a symbol is displayed, also
2454 display the file offset of the region of data that is about to be
2455 dumped. If zeroes are being skipped, then when disassembly resumes,
2456 tell the user how many zeroes were skipped and the file offset of the
2457 location from where the disassembly resumes. When dumping sections,
2458 display the file offset of the location from where the dump starts.
2459
2460 @item --file-start-context
2461 @cindex source code context
2462 Specify that when displaying interlisted source code/disassembly
2463 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2464 context to the start of the file.
2465
2466 @item -h
2467 @itemx --section-headers
2468 @itemx --headers
2469 @cindex section headers
2470 Display summary information from the section headers of the
2471 object file.
2472
2473 File segments may be relocated to nonstandard addresses, for example by
2474 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2475 @command{ld}. However, some object file formats, such as a.out, do not
2476 store the starting address of the file segments. In those situations,
2477 although @command{ld} relocates the sections correctly, using @samp{objdump
2478 -h} to list the file section headers cannot show the correct addresses.
2479 Instead, it shows the usual addresses, which are implicit for the
2480 target.
2481
2482 Note, in some cases it is possible for a section to have both the
2483 READONLY and the NOREAD attributes set. In such cases the NOREAD
2484 attribute takes precedence, but @command{objdump} will report both
2485 since the exact setting of the flag bits might be important.
2486
2487 @item -H
2488 @itemx --help
2489 Print a summary of the options to @command{objdump} and exit.
2490
2491 @item -i
2492 @itemx --info
2493 @cindex architectures available
2494 @cindex object formats available
2495 Display a list showing all architectures and object formats available
2496 for specification with @option{-b} or @option{-m}.
2497
2498 @item -j @var{name}
2499 @itemx --section=@var{name}
2500 @cindex section information
2501 Display information only for section @var{name}.
2502
2503 @item -L
2504 @itemx --process-links
2505 Display the contents of non-debug sections found in separate debuginfo
2506 files that are linked to the main file. This option automatically
2507 implies the @option{-WK} option, and only sections requested by other
2508 command line options will be displayed.
2509
2510 @item -l
2511 @itemx --line-numbers
2512 @cindex source filenames for object files
2513 Label the display (using debugging information) with the filename and
2514 source line numbers corresponding to the object code or relocs shown.
2515 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2516
2517 @item -m @var{machine}
2518 @itemx --architecture=@var{machine}
2519 @cindex architecture
2520 @cindex disassembly architecture
2521 Specify the architecture to use when disassembling object files. This
2522 can be useful when disassembling object files which do not describe
2523 architecture information, such as S-records. You can list the available
2524 architectures with the @option{-i} option.
2525
2526 If the target is an ARM architecture then this switch has an
2527 additional effect. It restricts the disassembly to only those
2528 instructions supported by the architecture specified by @var{machine}.
2529 If it is necessary to use this switch because the input file does not
2530 contain any architecture information, but it is also desired to
2531 disassemble all the instructions use @option{-marm}.
2532
2533 @item -M @var{options}
2534 @itemx --disassembler-options=@var{options}
2535 Pass target specific information to the disassembler. Only supported on
2536 some targets. If it is necessary to specify more than one
2537 disassembler option then multiple @option{-M} options can be used or
2538 can be placed together into a comma separated list.
2539
2540 For ARC, @option{dsp} controls the printing of DSP instructions,
2541 @option{spfp} selects the printing of FPX single precision FP
2542 instructions, @option{dpfp} selects the printing of FPX double
2543 precision FP instructions, @option{quarkse_em} selects the printing of
2544 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2545 of double precision assist instructions, @option{fpus} selects the
2546 printing of FPU single precision FP instructions, while @option{fpud}
2547 selects the printing of FPU double precision FP instructions.
2548 Additionally, one can choose to have all the immediates printed in
2549 hexadecimal using @option{hex}. By default, the short immediates are
2550 printed using the decimal representation, while the long immediate
2551 values are printed as hexadecimal.
2552
2553 @option{cpu=...} allows one to enforce a particular ISA when disassembling
2554 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2555 This might be useful to select ARC EM or HS ISA, because architecture is same
2556 for those and disassembler relies on private ELF header data to decide if code
2557 is for EM or HS. This option might be specified multiple times - only the
2558 latest value will be used. Valid values are same as for the assembler
2559 @option{-mcpu=...} option.
2560
2561 If the target is an ARM architecture then this switch can be used to
2562 select which register name set is used during disassembler. Specifying
2563 @option{-M reg-names-std} (the default) will select the register names as
2564 used in ARM's instruction set documentation, but with register 13 called
2565 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2566 @option{-M reg-names-apcs} will select the name set used by the ARM
2567 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2568 just use @samp{r} followed by the register number.
2569
2570 There are also two variants on the APCS register naming scheme enabled
2571 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2572 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2573 with the normal register names or the special register names).
2574
2575 This option can also be used for ARM architectures to force the
2576 disassembler to interpret all instructions as Thumb instructions by
2577 using the switch @option{--disassembler-options=force-thumb}. This can be
2578 useful when attempting to disassemble thumb code produced by other
2579 compilers.
2580
2581 For AArch64 targets this switch can be used to set whether instructions are
2582 disassembled as the most general instruction using the @option{-M no-aliases}
2583 option or whether instruction notes should be generated as comments in the
2584 disasssembly using @option{-M notes}.
2585
2586 For the x86, some of the options duplicate functions of the @option{-m}
2587 switch, but allow finer grained control.
2588 @table @code
2589 @item x86-64
2590 @itemx i386
2591 @itemx i8086
2592 Select disassembly for the given architecture.
2593
2594 @item intel
2595 @itemx att
2596 Select between intel syntax mode and AT&T syntax mode.
2597
2598 @item amd64
2599 @itemx intel64
2600 Select between AMD64 ISA and Intel64 ISA.
2601
2602 @item intel-mnemonic
2603 @itemx att-mnemonic
2604 Select between intel mnemonic mode and AT&T mnemonic mode.
2605 Note: @code{intel-mnemonic} implies @code{intel} and
2606 @code{att-mnemonic} implies @code{att}.
2607
2608 @item addr64
2609 @itemx addr32
2610 @itemx addr16
2611 @itemx data32
2612 @itemx data16
2613 Specify the default address size and operand size. These five options
2614 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2615 appear later in the option string.
2616
2617 @item suffix
2618 When in AT&T mode and also for a limited set of instructions when in Intel
2619 mode, instructs the disassembler to print a mnemonic suffix even when the
2620 suffix could be inferred by the operands or, for certain instructions, the
2621 execution mode's defaults.
2622 @end table
2623
2624 For PowerPC, the @option{-M} argument @option{raw} selects
2625 disasssembly of hardware insns rather than aliases. For example, you
2626 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2627 rather than @code{li}. All of the @option{-m} arguments for
2628 @command{gas} that select a CPU are supported. These are:
2629 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2630 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2631 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2632 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2633 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2634 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2635 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2636 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2637 @option{power8}, @option{power9}, @option{power10}, @option{ppc},
2638 @option{ppc32}, @option{ppc64}, @option{ppc64bridge}, @option{ppcps},
2639 @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2640 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9}, @option{pwr10},
2641 @option{pwrx}, @option{titan}, @option{vle}, and @option{future}.
2642 @option{32} and @option{64} modify the default or a prior CPU
2643 selection, disabling and enabling 64-bit insns respectively. In
2644 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2645 and @option{spe} add capabilities to a previous @emph{or later} CPU
2646 selection. @option{any} will disassemble any opcode known to
2647 binutils, but in cases where an opcode has two different meanings or
2648 different arguments, you may not see the disassembly you expect.
2649 If you disassemble without giving a CPU selection, a default will be
2650 chosen from information gleaned by BFD from the object files headers,
2651 but the result again may not be as you expect.
2652
2653 For MIPS, this option controls the printing of instruction mnemonic
2654 names and register names in disassembled instructions. Multiple
2655 selections from the following may be specified as a comma separated
2656 string, and invalid options are ignored:
2657
2658 @table @code
2659 @item no-aliases
2660 Print the 'raw' instruction mnemonic instead of some pseudo
2661 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2662 'sll' instead of 'nop', etc.
2663
2664 @item msa
2665 Disassemble MSA instructions.
2666
2667 @item virt
2668 Disassemble the virtualization ASE instructions.
2669
2670 @item xpa
2671 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2672
2673 @item gpr-names=@var{ABI}
2674 Print GPR (general-purpose register) names as appropriate
2675 for the specified ABI. By default, GPR names are selected according to
2676 the ABI of the binary being disassembled.
2677
2678 @item fpr-names=@var{ABI}
2679 Print FPR (floating-point register) names as
2680 appropriate for the specified ABI. By default, FPR numbers are printed
2681 rather than names.
2682
2683 @item cp0-names=@var{ARCH}
2684 Print CP0 (system control coprocessor; coprocessor 0) register names
2685 as appropriate for the CPU or architecture specified by
2686 @var{ARCH}. By default, CP0 register names are selected according to
2687 the architecture and CPU of the binary being disassembled.
2688
2689 @item hwr-names=@var{ARCH}
2690 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2691 as appropriate for the CPU or architecture specified by
2692 @var{ARCH}. By default, HWR names are selected according to
2693 the architecture and CPU of the binary being disassembled.
2694
2695 @item reg-names=@var{ABI}
2696 Print GPR and FPR names as appropriate for the selected ABI.
2697
2698 @item reg-names=@var{ARCH}
2699 Print CPU-specific register names (CP0 register and HWR names)
2700 as appropriate for the selected CPU or architecture.
2701 @end table
2702
2703 For any of the options listed above, @var{ABI} or
2704 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2705 rather than names, for the selected types of registers.
2706 You can list the available values of @var{ABI} and @var{ARCH} using
2707 the @option{--help} option.
2708
2709 For VAX, you can specify function entry addresses with @option{-M
2710 entry:0xf00ba}. You can use this multiple times to properly
2711 disassemble VAX binary files that don't contain symbol tables (like
2712 ROM dumps). In these cases, the function entry mask would otherwise
2713 be decoded as VAX instructions, which would probably lead the rest
2714 of the function being wrongly disassembled.
2715
2716 @item -p
2717 @itemx --private-headers
2718 Print information that is specific to the object file format. The exact
2719 information printed depends upon the object file format. For some
2720 object file formats, no additional information is printed.
2721
2722 @item -P @var{options}
2723 @itemx --private=@var{options}
2724 Print information that is specific to the object file format. The
2725 argument @var{options} is a comma separated list that depends on the
2726 format (the lists of options is displayed with the help).
2727
2728 For XCOFF, the available options are:
2729 @table @code
2730 @item header
2731 @item aout
2732 @item sections
2733 @item syms
2734 @item relocs
2735 @item lineno,
2736 @item loader
2737 @item except
2738 @item typchk
2739 @item traceback
2740 @item toc
2741 @item ldinfo
2742 @end table
2743
2744 Not all object formats support this option. In particular the ELF
2745 format does not use it.
2746
2747 @item -r
2748 @itemx --reloc
2749 @cindex relocation entries, in object file
2750 Print the relocation entries of the file. If used with @option{-d} or
2751 @option{-D}, the relocations are printed interspersed with the
2752 disassembly.
2753
2754 @item -R
2755 @itemx --dynamic-reloc
2756 @cindex dynamic relocation entries, in object file
2757 Print the dynamic relocation entries of the file. This is only
2758 meaningful for dynamic objects, such as certain types of shared
2759 libraries. As for @option{-r}, if used with @option{-d} or
2760 @option{-D}, the relocations are printed interspersed with the
2761 disassembly.
2762
2763 @item -s
2764 @itemx --full-contents
2765 @cindex sections, full contents
2766 @cindex object file sections
2767 Display the full contents of any sections requested. By default all
2768 non-empty sections are displayed.
2769
2770 @item -S
2771 @itemx --source
2772 @cindex source disassembly
2773 @cindex disassembly, with source
2774 Display source code intermixed with disassembly, if possible. Implies
2775 @option{-d}.
2776
2777 @item --source-comment[=@var{txt}]
2778 @cindex source disassembly
2779 @cindex disassembly, with source
2780 Like the @option{-S} option, but all source code lines are displayed
2781 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2782 string which can be used to distinguish the assembler code from the
2783 source code. If @var{txt} is not provided then a default string of
2784 @var{``# ``} (hash followed by a space), will be used.
2785
2786 @item --prefix=@var{prefix}
2787 @cindex Add prefix to absolute paths
2788 Specify @var{prefix} to add to the absolute paths when used with
2789 @option{-S}.
2790
2791 @item --prefix-strip=@var{level}
2792 @cindex Strip absolute paths
2793 Indicate how many initial directory names to strip off the hardwired
2794 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2795
2796 @item --show-raw-insn
2797 When disassembling instructions, print the instruction in hex as well as
2798 in symbolic form. This is the default except when
2799 @option{--prefix-addresses} is used.
2800
2801 @item --no-show-raw-insn
2802 When disassembling instructions, do not print the instruction bytes.
2803 This is the default when @option{--prefix-addresses} is used.
2804
2805 @item --insn-width=@var{width}
2806 @cindex Instruction width
2807 Display @var{width} bytes on a single line when disassembling
2808 instructions.
2809
2810 @item --visualize-jumps[=color|=extended-color|=off]
2811 Visualize jumps that stay inside a function by drawing ASCII art between
2812 the start and target addresses. The optional @option{=color} argument
2813 adds color to the output using simple terminal colors. Alternatively
2814 the @option{=extended-color} argument will add color using 8bit
2815 colors, but these might not work on all terminals.
2816
2817 If it is necessary to disable the @option{visualize-jumps} option
2818 after it has previously been enabled then use
2819 @option{visualize-jumps=off}.
2820
2821 @item --disassembler-color=[color|extended-color|off]
2822 Apply syntax highlighting to the disassembler output. The
2823 @option{color} argument adds color using simple terminal colors.
2824 Alternatively the @option{extended-color} argument will use 8bit
2825 colors, but these might not work on all terminals.
2826
2827 If it is necessary to disable the @option{--disassembler-color} option
2828 after it has previously been enabled then use
2829 @option{--disassembler-color=off}.
2830
2831 If this option is not specified then the default is to enable color
2832 output if displaying to a terminal, but not otherwise.
2833
2834 @item -W[lLiaprmfFsoORtUuTgAckK]
2835 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
2836 @include debug.options.texi
2837
2838 @item --dwarf-check
2839 Enable additional checks for consistency of Dwarf information.
2840
2841 @include ctf.options.texi
2842
2843 @item -G
2844 @itemx --stabs
2845 @cindex stab
2846 @cindex .stab
2847 @cindex debug symbols
2848 @cindex ELF object file format
2849 Display the full contents of any sections requested. Display the
2850 contents of the .stab and .stab.index and .stab.excl sections from an
2851 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2852 @code{.stab} debugging symbol-table entries are carried in an ELF
2853 section. In most other file formats, debugging symbol-table entries are
2854 interleaved with linkage symbols, and are visible in the @option{--syms}
2855 output.
2856
2857 @item --start-address=@var{address}
2858 @cindex start-address
2859 Start displaying data at the specified address. This affects the output
2860 of the @option{-d}, @option{-r} and @option{-s} options.
2861
2862 @item --stop-address=@var{address}
2863 @cindex stop-address
2864 Stop displaying data at the specified address. This affects the output
2865 of the @option{-d}, @option{-r} and @option{-s} options.
2866
2867 @item -t
2868 @itemx --syms
2869 @cindex symbol table entries, printing
2870 Print the symbol table entries of the file.
2871 This is similar to the information provided by the @samp{nm} program,
2872 although the display format is different. The format of the output
2873 depends upon the format of the file being dumped, but there are two main
2874 types. One looks like this:
2875
2876 @smallexample
2877 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2878 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2879 @end smallexample
2880
2881 where the number inside the square brackets is the number of the entry
2882 in the symbol table, the @var{sec} number is the section number, the
2883 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2884 symbol's type, the @var{scl} number is the symbol's storage class and
2885 the @var{nx} value is the number of auxiliary entries associated with
2886 the symbol. The last two fields are the symbol's value and its name.
2887
2888 The other common output format, usually seen with ELF based files,
2889 looks like this:
2890
2891 @smallexample
2892 00000000 l d .bss 00000000 .bss
2893 00000000 g .text 00000000 fred
2894 @end smallexample
2895
2896 Here the first number is the symbol's value (sometimes referred to as
2897 its address). The next field is actually a set of characters and
2898 spaces indicating the flag bits that are set on the symbol. These
2899 characters are described below. Next is the section with which the
2900 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2901 not connected with any section), or @emph{*UND*} if the section is
2902 referenced in the file being dumped, but not defined there.
2903
2904 After the section name comes another field, a number, which for common
2905 symbols is the alignment and for other symbol is the size. Finally
2906 the symbol's name is displayed.
2907
2908 The flag characters are divided into 7 groups as follows:
2909 @table @code
2910 @item l
2911 @itemx g
2912 @itemx u
2913 @itemx !
2914 The symbol is a local (l), global (g), unique global (u), neither
2915 global nor local (a space) or both global and local (!). A
2916 symbol can be neither local or global for a variety of reasons, e.g.,
2917 because it is used for debugging, but it is probably an indication of
2918 a bug if it is ever both local and global. Unique global symbols are
2919 a GNU extension to the standard set of ELF symbol bindings. For such
2920 a symbol the dynamic linker will make sure that in the entire process
2921 there is just one symbol with this name and type in use.
2922
2923 @item w
2924 The symbol is weak (w) or strong (a space).
2925
2926 @item C
2927 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2928
2929 @item W
2930 The symbol is a warning (W) or a normal symbol (a space). A warning
2931 symbol's name is a message to be displayed if the symbol following the
2932 warning symbol is ever referenced.
2933
2934 @item I
2935 @item i
2936 The symbol is an indirect reference to another symbol (I), a function
2937 to be evaluated during reloc processing (i) or a normal symbol (a
2938 space).
2939
2940 @item d
2941 @itemx D
2942 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2943 normal symbol (a space).
2944
2945 @item F
2946 @item f
2947 @item O
2948 The symbol is the name of a function (F) or a file (f) or an object
2949 (O) or just a normal symbol (a space).
2950 @end table
2951
2952 @item -T
2953 @itemx --dynamic-syms
2954 @cindex dynamic symbol table entries, printing
2955 Print the dynamic symbol table entries of the file. This is only
2956 meaningful for dynamic objects, such as certain types of shared
2957 libraries. This is similar to the information provided by the @samp{nm}
2958 program when given the @option{-D} (@option{--dynamic}) option.
2959
2960 The output format is similar to that produced by the @option{--syms}
2961 option, except that an extra field is inserted before the symbol's
2962 name, giving the version information associated with the symbol.
2963 If the version is the default version to be used when resolving
2964 unversioned references to the symbol then it's displayed as is,
2965 otherwise it's put into parentheses.
2966
2967 @item --special-syms
2968 When displaying symbols include those which the target considers to be
2969 special in some way and which would not normally be of interest to the
2970 user.
2971
2972 @item -U @var{[d|i|l|e|x|h]}
2973 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
2974 Controls the display of UTF-8 encoded multibyte characters in strings.
2975 The default (@option{--unicode=default}) is to give them no special
2976 treatment. The @option{--unicode=locale} option displays the sequence
2977 in the current locale, which may or may not support them. The options
2978 @option{--unicode=hex} and @option{--unicode=invalid} display them as
2979 hex byte sequences enclosed by either angle brackets or curly braces.
2980
2981 The @option{--unicode=escape} option displays them as escape sequences
2982 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
2983 them as escape sequences highlighted in red (if supported by the
2984 output device). The colouring is intended to draw attention to the
2985 presence of unicode sequences where they might not be expected.
2986
2987 @item -V
2988 @itemx --version
2989 Print the version number of @command{objdump} and exit.
2990
2991 @item -x
2992 @itemx --all-headers
2993 @cindex all header information, object file
2994 @cindex header information, all
2995 Display all available header information, including the symbol table and
2996 relocation entries. Using @option{-x} is equivalent to specifying all of
2997 @option{-a -f -h -p -r -t}.
2998
2999 @item -w
3000 @itemx --wide
3001 @cindex wide output, printing
3002 Format some lines for output devices that have more than 80 columns.
3003 Also do not truncate symbol names when they are displayed.
3004
3005 @item -z
3006 @itemx --disassemble-zeroes
3007 Normally the disassembly output will skip blocks of zeroes. This
3008 option directs the disassembler to disassemble those blocks, just like
3009 any other data.
3010 @end table
3011
3012 @c man end
3013
3014 @ignore
3015 @c man begin SEEALSO objdump
3016 nm(1), readelf(1), and the Info entries for @file{binutils}.
3017 @c man end
3018 @end ignore
3019
3020 @node ranlib
3021 @chapter ranlib
3022
3023 @kindex ranlib
3024 @cindex archive contents
3025 @cindex symbol index
3026
3027 @c man title ranlib generate an index to an archive
3028
3029 @smallexample
3030 @c man begin SYNOPSIS ranlib
3031 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
3032 @c man end
3033 @end smallexample
3034
3035 @c man begin DESCRIPTION ranlib
3036
3037 @command{ranlib} generates an index to the contents of an archive and
3038 stores it in the archive. The index lists each symbol defined by a
3039 member of an archive that is a relocatable object file.
3040
3041 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
3042
3043 An archive with such an index speeds up linking to the library and
3044 allows routines in the library to call each other without regard to
3045 their placement in the archive.
3046
3047 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
3048 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
3049 @xref{ar}.
3050
3051 @c man end
3052
3053 @c man begin OPTIONS ranlib
3054
3055 @table @env
3056 @item -h
3057 @itemx -H
3058 @itemx --help
3059 Show usage information for @command{ranlib}.
3060
3061 @item -v
3062 @itemx -V
3063 @itemx --version
3064 Show the version number of @command{ranlib}.
3065
3066 @item -D
3067 @cindex deterministic archives
3068 @kindex --enable-deterministic-archives
3069 Operate in @emph{deterministic} mode. The symbol map archive member's
3070 header will show zero for the UID, GID, and timestamp. When this
3071 option is used, multiple runs will produce identical output files.
3072
3073 If @file{binutils} was configured with
3074 @option{--enable-deterministic-archives}, then this mode is on by
3075 default. It can be disabled with the @samp{-U} option, described
3076 below.
3077
3078 @item -t
3079 Update the timestamp of the symbol map of an archive.
3080
3081 @item -U
3082 @cindex deterministic archives
3083 @kindex --enable-deterministic-archives
3084 Do @emph{not} operate in @emph{deterministic} mode. This is the
3085 inverse of the @samp{-D} option, above: the archive index will get
3086 actual UID, GID, timestamp, and file mode values.
3087
3088 If @file{binutils} was configured @emph{without}
3089 @option{--enable-deterministic-archives}, then this mode is on by
3090 default.
3091
3092 @end table
3093
3094 @c man end
3095
3096 @ignore
3097 @c man begin SEEALSO ranlib
3098 ar(1), nm(1), and the Info entries for @file{binutils}.
3099 @c man end
3100 @end ignore
3101
3102 @node size
3103 @chapter size
3104
3105 @kindex size
3106 @cindex section sizes
3107
3108 @c man title size list section sizes and total size of binary files
3109
3110 @smallexample
3111 @c man begin SYNOPSIS size
3112 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
3113 [@option{--help}]
3114 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
3115 [@option{--common}]
3116 [@option{-t}|@option{--totals}]
3117 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
3118 [@var{objfile}@dots{}]
3119 @c man end
3120 @end smallexample
3121
3122 @c man begin DESCRIPTION size
3123
3124 The @sc{gnu} @command{size} utility lists the section sizes and the total
3125 size for each of the binary files @var{objfile} on its argument list.
3126 By default, one line of output is generated for each file or each
3127 module if the file is an archive.
3128
3129 @var{objfile}@dots{} are the files to be examined. If none are
3130 specified, the file @code{a.out} will be used instead.
3131
3132 @c man end
3133
3134 @c man begin OPTIONS size
3135
3136 The command-line options have the following meanings:
3137
3138 @table @env
3139 @item -A
3140 @itemx -B
3141 @itemx -G
3142 @itemx --format=@var{compatibility}
3143 @cindex @command{size} display format
3144 Using one of these options, you can choose whether the output from @sc{gnu}
3145 @command{size} resembles output from System V @command{size} (using @option{-A},
3146 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3147 @option{--format=berkeley}). The default is the one-line format similar to
3148 Berkeley's. Alternatively, you can choose the GNU format output
3149 (using @option{-G}, or @option{--format=gnu}), this is similar to
3150 Berkeley's output format, but sizes are counted differently.
3151 @c Bonus for doc-source readers: you can also say --format=strange (or
3152 @c anything else that starts with 's') for sysv, and --format=boring (or
3153 @c anything else that starts with 'b') for Berkeley.
3154
3155 Here is an example of the Berkeley (default) format of output from
3156 @command{size}:
3157 @smallexample
3158 $ size --format=Berkeley ranlib size
3159 text data bss dec hex filename
3160 294880 81920 11592 388392 5ed28 ranlib
3161 294880 81920 11888 388688 5ee50 size
3162 @end smallexample
3163
3164 The Berkeley style output counts read only data in the @code{text}
3165 column, not in the @code{data} column, the @code{dec} and @code{hex}
3166 columns both display the sum of the @code{text}, @code{data}, and
3167 @code{bss} columns in decimal and hexadecimal respectively.
3168
3169 The GNU format counts read only data in the @code{data} column, not
3170 the @code{text} column, and only displays the sum of the @code{text},
3171 @code{data}, and @code{bss} columns once, in the @code{total} column.
3172 The @option{--radix} option can be used to change the number base for
3173 all columns. Here is the same data displayed with GNU conventions:
3174
3175 @smallexample
3176 $ size --format=GNU ranlib size
3177 text data bss total filename
3178 279880 96920 11592 388392 ranlib
3179 279880 96920 11888 388688 size
3180 @end smallexample
3181
3182 @noindent
3183 This is the same data, but displayed closer to System V conventions:
3184
3185 @smallexample
3186 $ size --format=SysV ranlib size
3187 ranlib :
3188 section size addr
3189 .text 294880 8192
3190 .data 81920 303104
3191 .bss 11592 385024
3192 Total 388392
3193
3194
3195 size :
3196 section size addr
3197 .text 294880 8192
3198 .data 81920 303104
3199 .bss 11888 385024
3200 Total 388688
3201 @end smallexample
3202
3203 @item --help
3204 Show a summary of acceptable arguments and options.
3205
3206 @item -d
3207 @itemx -o
3208 @itemx -x
3209 @itemx --radix=@var{number}
3210 @cindex @command{size} number format
3211 @cindex radix for section sizes
3212 Using one of these options, you can control whether the size of each
3213 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3214 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3215 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3216 values (8, 10, 16) are supported. The total size is always given in two
3217 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3218 octal and hexadecimal if you're using @option{-o}.
3219
3220 @item --common
3221 Print total size of common symbols in each file. When using Berkeley
3222 or GNU format these are included in the bss size.
3223
3224 @item -t
3225 @itemx --totals
3226 Show totals of all objects listed (Berkeley or GNU format mode only).
3227
3228 @item --target=@var{bfdname}
3229 @cindex object code format
3230 Specify that the object-code format for @var{objfile} is
3231 @var{bfdname}. This option may not be necessary; @command{size} can
3232 automatically recognize many formats.
3233 @xref{Target Selection}, for more information.
3234
3235 @item -V
3236 @itemx --version
3237 Display the version number of @command{size}.
3238 @end table
3239
3240 @c man end
3241
3242 @ignore
3243 @c man begin SEEALSO size
3244 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3245 @c man end
3246 @end ignore
3247
3248 @node strings
3249 @chapter strings
3250 @kindex strings
3251 @cindex listings strings
3252 @cindex printing strings
3253 @cindex strings, printing
3254
3255 @c man title strings print the sequences of printable characters in files
3256
3257 @smallexample
3258 @c man begin SYNOPSIS strings
3259 strings [@option{-afovV}] [@option{-}@var{min-len}]
3260 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3261 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3262 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3263 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
3264 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3265 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3266 [@option{-w}] [@option{--include-all-whitespace}]
3267 [@option{-s}] [@option{--output-separator} @var{sep_string}]
3268 [@option{--help}] [@option{--version}] @var{file}@dots{}
3269 @c man end
3270 @end smallexample
3271
3272 @c man begin DESCRIPTION strings
3273
3274 For each @var{file} given, @sc{gnu} @command{strings} prints the
3275 printable character sequences that are at least 4 characters long (or
3276 the number given with the options below) and are followed by an
3277 unprintable character.
3278
3279 Depending upon how the strings program was configured it will default
3280 to either displaying all the printable sequences that it can find in
3281 each file, or only those sequences that are in loadable, initialized
3282 data sections. If the file type is unrecognizable, or if strings is
3283 reading from stdin then it will always display all of the printable
3284 sequences that it can find.
3285
3286 For backwards compatibility any file that occurs after a command-line
3287 option of just @option{-} will also be scanned in full, regardless of
3288 the presence of any @option{-d} option.
3289
3290 @command{strings} is mainly useful for determining the contents of
3291 non-text files.
3292
3293 @c man end
3294
3295 @c man begin OPTIONS strings
3296
3297 @table @env
3298 @item -a
3299 @itemx --all
3300 @itemx -
3301 Scan the whole file, regardless of what sections it contains or
3302 whether those sections are loaded or initialized. Normally this is
3303 the default behaviour, but strings can be configured so that the
3304 @option{-d} is the default instead.
3305
3306 The @option{-} option is position dependent and forces strings to
3307 perform full scans of any file that is mentioned after the @option{-}
3308 on the command line, even if the @option{-d} option has been
3309 specified.
3310
3311 @item -d
3312 @itemx --data
3313 Only print strings from initialized, loaded data sections in the
3314 file. This may reduce the amount of garbage in the output, but it
3315 also exposes the strings program to any security flaws that may be
3316 present in the BFD library used to scan and load sections. Strings
3317 can be configured so that this option is the default behaviour. In
3318 such cases the @option{-a} option can be used to avoid using the BFD
3319 library and instead just print all of the strings found in the file.
3320
3321 @item -f
3322 @itemx --print-file-name
3323 Print the name of the file before each string.
3324
3325 @item --help
3326 Print a summary of the program usage on the standard output and exit.
3327
3328 @item -@var{min-len}
3329 @itemx -n @var{min-len}
3330 @itemx --bytes=@var{min-len}
3331 Print sequences of displayable characters that are at least
3332 @var{min-len} characters long. If not specified a default minimum
3333 length of 4 is used. The distinction between displayable and
3334 non-displayable characters depends upon the setting of the
3335 @option{-e} and @option{-U} options. Sequences are always terminated
3336 at control characters such as new-line and carriage-return, but not
3337 the tab character.
3338
3339 @item -o
3340 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3341 act like @samp{-t d} instead. Since we can not be compatible with both
3342 ways, we simply chose one.
3343
3344 @item -t @var{radix}
3345 @itemx --radix=@var{radix}
3346 Print the offset within the file before each string. The single
3347 character argument specifies the radix of the offset---@samp{o} for
3348 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3349
3350 @item -e @var{encoding}
3351 @itemx --encoding=@var{encoding}
3352 Select the character encoding of the strings that are to be found.
3353 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3354 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3355 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3356 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3357 littleendian. Useful for finding wide character strings. (@samp{l}
3358 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3359
3360 @item -U @var{[d|i|l|e|x|h]}
3361 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3362 Controls the display of UTF-8 encoded multibyte characters in strings.
3363 The default (@option{--unicode=default}) is to give them no special
3364 treatment, and instead rely upon the setting of the
3365 @option{--encoding} option. The other values for this option
3366 automatically enable @option{--encoding=S}.
3367
3368 The @option{--unicode=invalid} option treats them as non-graphic
3369 characters and hence not part of a valid string. All the remaining
3370 options treat them as valid string characters.
3371
3372 The @option{--unicode=locale} option displays them in the current
3373 locale, which may or may not support UTF-8 encoding. The
3374 @option{--unicode=hex} option displays them as hex byte sequences
3375 enclosed between @var{<>} characters. The @option{--unicode=escape}
3376 option displays them as escape sequences (@var{\uxxxx}) and the
3377 @option{--unicode=highlight} option displays them as escape sequences
3378 highlighted in red (if supported by the output device). The colouring
3379 is intended to draw attention to the presence of unicode sequences
3380 where they might not be expected.
3381
3382 @item -T @var{bfdname}
3383 @itemx --target=@var{bfdname}
3384 @cindex object code format
3385 Specify an object code format other than your system's default format.
3386 @xref{Target Selection}, for more information.
3387
3388 @item -v
3389 @itemx -V
3390 @itemx --version
3391 Print the program version number on the standard output and exit.
3392
3393 @item -w
3394 @itemx --include-all-whitespace
3395 By default tab and space characters are included in the strings that
3396 are displayed, but other whitespace characters, such a newlines and
3397 carriage returns, are not. The @option{-w} option changes this so
3398 that all whitespace characters are considered to be part of a string.
3399
3400 @item -s
3401 @itemx --output-separator
3402 By default, output strings are delimited by a new-line. This option
3403 allows you to supply any string to be used as the output record
3404 separator. Useful with --include-all-whitespace where strings
3405 may contain new-lines internally.
3406 @end table
3407
3408 @c man end
3409
3410 @ignore
3411 @c man begin SEEALSO strings
3412 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3413 and the Info entries for @file{binutils}.
3414 @c man end
3415 @end ignore
3416
3417 @node strip
3418 @chapter strip
3419
3420 @kindex strip
3421 @cindex removing symbols
3422 @cindex discarding symbols
3423 @cindex symbols, discarding
3424
3425 @c man title strip discard symbols and other data from object files
3426
3427 @smallexample
3428 @c man begin SYNOPSIS strip
3429 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3430 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3431 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3432 [@option{-s}|@option{--strip-all}]
3433 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3434 [@option{--strip-dwo}]
3435 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3436 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3437 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3438 [@option{-w}|@option{--wildcard}]
3439 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3440 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3441 [@option{--keep-section=}@var{sectionpattern}]
3442 [@option{--remove-relocations=}@var{sectionpattern}]
3443 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3444 [@option{-D}|@option{--enable-deterministic-archives}]
3445 [@option{-U}|@option{--disable-deterministic-archives}]
3446 [@option{--keep-section-symbols}]
3447 [@option{--keep-file-symbols}]
3448 [@option{--only-keep-debug}]
3449 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3450 [@option{--help}] [@option{--info}]
3451 @var{objfile}@dots{}
3452 @c man end
3453 @end smallexample
3454
3455 @c man begin DESCRIPTION strip
3456
3457 @sc{gnu} @command{strip} discards all symbols from object files
3458 @var{objfile}. The list of object files may include archives.
3459 At least one object file must be given.
3460
3461 @command{strip} modifies the files named in its argument,
3462 rather than writing modified copies under different names.
3463
3464 @c man end
3465
3466 @c man begin OPTIONS strip
3467
3468 @table @env
3469 @item -F @var{bfdname}
3470 @itemx --target=@var{bfdname}
3471 Treat the original @var{objfile} as a file with the object
3472 code format @var{bfdname}, and rewrite it in the same format.
3473 @xref{Target Selection}, for more information.
3474
3475 @item --help
3476 Show a summary of the options to @command{strip} and exit.
3477
3478 @item --info
3479 Display a list showing all architectures and object formats available.
3480
3481 @item -I @var{bfdname}
3482 @itemx --input-target=@var{bfdname}
3483 Treat the original @var{objfile} as a file with the object
3484 code format @var{bfdname}.
3485 @xref{Target Selection}, for more information.
3486
3487 @item -O @var{bfdname}
3488 @itemx --output-target=@var{bfdname}
3489 Replace @var{objfile} with a file in the output format @var{bfdname}.
3490 @xref{Target Selection}, for more information.
3491
3492 @item -R @var{sectionname}
3493 @itemx --remove-section=@var{sectionname}
3494 Remove any section named @var{sectionname} from the output file, in
3495 addition to whatever sections would otherwise be removed. This
3496 option may be given more than once. Note that using this option
3497 inappropriately may make the output file unusable. The wildcard
3498 character @samp{*} may be given at the end of @var{sectionname}. If
3499 so, then any section starting with @var{sectionname} will be removed.
3500
3501 If the first character of @var{sectionpattern} is the exclamation
3502 point (!) then matching sections will not be removed even if an
3503 earlier use of @option{--remove-section} on the same command line
3504 would otherwise remove it. For example:
3505
3506 @smallexample
3507 --remove-section=.text.* --remove-section=!.text.foo
3508 @end smallexample
3509
3510 will remove all sections matching the pattern '.text.*', but will not
3511 remove the section '.text.foo'.
3512
3513 @item --keep-section=@var{sectionpattern}
3514 When removing sections from the output file, keep sections that match
3515 @var{sectionpattern}.
3516
3517 @item --remove-relocations=@var{sectionpattern}
3518 Remove relocations from the output file for any section matching
3519 @var{sectionpattern}. This option may be given more than once. Note
3520 that using this option inappropriately may make the output file
3521 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3522 For example:
3523
3524 @smallexample
3525 --remove-relocations=.text.*
3526 @end smallexample
3527
3528 will remove the relocations for all sections matching the patter
3529 '.text.*'.
3530
3531 If the first character of @var{sectionpattern} is the exclamation
3532 point (!) then matching sections will not have their relocation
3533 removed even if an earlier use of @option{--remove-relocations} on the
3534 same command line would otherwise cause the relocations to be removed.
3535 For example:
3536
3537 @smallexample
3538 --remove-relocations=.text.* --remove-relocations=!.text.foo
3539 @end smallexample
3540
3541 will remove all relocations for sections matching the pattern
3542 '.text.*', but will not remove relocations for the section
3543 '.text.foo'.
3544
3545 @item -s
3546 @itemx --strip-all
3547 Remove all symbols.
3548
3549 @item -g
3550 @itemx -S
3551 @itemx -d
3552 @itemx --strip-debug
3553 Remove debugging symbols only.
3554
3555 @item --strip-dwo
3556 Remove the contents of all DWARF .dwo sections, leaving the
3557 remaining debugging sections and all symbols intact.
3558 See the description of this option in the @command{objcopy} section
3559 for more information.
3560
3561 @item --strip-unneeded
3562 Remove all symbols that are not needed for relocation processing in
3563 addition to debugging symbols and sections stripped by
3564 @option{--strip-debug}.
3565
3566 @item -K @var{symbolname}
3567 @itemx --keep-symbol=@var{symbolname}
3568 When stripping symbols, keep symbol @var{symbolname} even if it would
3569 normally be stripped. This option may be given more than once.
3570
3571 @item -M
3572 @itemx --merge-notes
3573 @itemx --no-merge-notes
3574 For ELF files, attempt (or do not attempt) to reduce the size of any
3575 SHT_NOTE type sections by removing duplicate notes. The default is to
3576 attempt this reduction unless stripping debug or DWO information.
3577
3578 @item -N @var{symbolname}
3579 @itemx --strip-symbol=@var{symbolname}
3580 Remove symbol @var{symbolname} from the source file. This option may be
3581 given more than once, and may be combined with strip options other than
3582 @option{-K}.
3583
3584 @item -o @var{file}
3585 Put the stripped output in @var{file}, rather than replacing the
3586 existing file. When this argument is used, only one @var{objfile}
3587 argument may be specified.
3588
3589 @item -p
3590 @itemx --preserve-dates
3591 Preserve the access and modification dates of the file.
3592
3593 @item -D
3594 @itemx --enable-deterministic-archives
3595 @cindex deterministic archives
3596 @kindex --enable-deterministic-archives
3597 Operate in @emph{deterministic} mode. When copying archive members
3598 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3599 and use consistent file modes for all files.
3600
3601 If @file{binutils} was configured with
3602 @option{--enable-deterministic-archives}, then this mode is on by default.
3603 It can be disabled with the @samp{-U} option, below.
3604
3605 @item -U
3606 @itemx --disable-deterministic-archives
3607 @cindex deterministic archives
3608 @kindex --enable-deterministic-archives
3609 Do @emph{not} operate in @emph{deterministic} mode. This is the
3610 inverse of the @option{-D} option, above: when copying archive members
3611 and writing the archive index, use their actual UID, GID, timestamp,
3612 and file mode values.
3613
3614 This is the default unless @file{binutils} was configured with
3615 @option{--enable-deterministic-archives}.
3616
3617 @item -w
3618 @itemx --wildcard
3619 Permit regular expressions in @var{symbolname}s used in other command
3620 line options. The question mark (?), asterisk (*), backslash (\) and
3621 square brackets ([]) operators can be used anywhere in the symbol
3622 name. If the first character of the symbol name is the exclamation
3623 point (!) then the sense of the switch is reversed for that symbol.
3624 For example:
3625
3626 @smallexample
3627 -w -K !foo -K fo*
3628 @end smallexample
3629
3630 would cause strip to only keep symbols that start with the letters
3631 ``fo'', but to discard the symbol ``foo''.
3632
3633 @item -x
3634 @itemx --discard-all
3635 Remove non-global symbols.
3636
3637 @item -X
3638 @itemx --discard-locals
3639 Remove compiler-generated local symbols.
3640 (These usually start with @samp{L} or @samp{.}.)
3641
3642 @item --keep-section-symbols
3643 When stripping a file, perhaps with @option{--strip-debug} or
3644 @option{--strip-unneeded}, retain any symbols specifying section names,
3645 which would otherwise get stripped.
3646
3647 @item --keep-file-symbols
3648 When stripping a file, perhaps with @option{--strip-debug} or
3649 @option{--strip-unneeded}, retain any symbols specifying source file names,
3650 which would otherwise get stripped.
3651
3652 @item --only-keep-debug
3653 Strip a file, emptying the contents of any sections that would not be
3654 stripped by @option{--strip-debug} and leaving the debugging sections
3655 intact. In ELF files, this preserves all the note sections in the
3656 output as well.
3657
3658 Note - the section headers of the stripped sections are preserved,
3659 including their sizes, but the contents of the section are discarded.
3660 The section headers are preserved so that other tools can match up the
3661 debuginfo file with the real executable, even if that executable has
3662 been relocated to a different address space.
3663
3664 The intention is that this option will be used in conjunction with
3665 @option{--add-gnu-debuglink} to create a two part executable. One a
3666 stripped binary which will occupy less space in RAM and in a
3667 distribution and the second a debugging information file which is only
3668 needed if debugging abilities are required. The suggested procedure
3669 to create these files is as follows:
3670
3671 @enumerate
3672 @item Link the executable as normal. Assuming that it is called
3673 @code{foo} then...
3674 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3675 create a file containing the debugging info.
3676 @item Run @code{objcopy --strip-debug foo} to create a
3677 stripped executable.
3678 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3679 to add a link to the debugging info into the stripped executable.
3680 @end enumerate
3681
3682 Note---the choice of @code{.dbg} as an extension for the debug info
3683 file is arbitrary. Also the @code{--only-keep-debug} step is
3684 optional. You could instead do this:
3685
3686 @enumerate
3687 @item Link the executable as normal.
3688 @item Copy @code{foo} to @code{foo.full}
3689 @item Run @code{strip --strip-debug foo}
3690 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3691 @end enumerate
3692
3693 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3694 full executable. It does not have to be a file created by the
3695 @option{--only-keep-debug} switch.
3696
3697 Note---this switch is only intended for use on fully linked files. It
3698 does not make sense to use it on object files where the debugging
3699 information may be incomplete. Besides the gnu_debuglink feature
3700 currently only supports the presence of one filename containing
3701 debugging information, not multiple filenames on a one-per-object-file
3702 basis.
3703
3704 @item -V
3705 @itemx --version
3706 Show the version number for @command{strip}.
3707
3708 @item -v
3709 @itemx --verbose
3710 Verbose output: list all object files modified. In the case of
3711 archives, @samp{strip -v} lists all members of the archive.
3712 @end table
3713
3714 @c man end
3715
3716 @ignore
3717 @c man begin SEEALSO strip
3718 the Info entries for @file{binutils}.
3719 @c man end
3720 @end ignore
3721
3722 @node c++filt, addr2line, strip, Top
3723 @chapter c++filt
3724
3725 @kindex c++filt
3726 @cindex demangling C++ symbols
3727
3728 @c man title cxxfilt demangle C++ and Java symbols
3729
3730 @smallexample
3731 @c man begin SYNOPSIS cxxfilt
3732 c++filt [@option{-_}|@option{--strip-underscore}]
3733 [@option{-n}|@option{--no-strip-underscore}]
3734 [@option{-p}|@option{--no-params}]
3735 [@option{-t}|@option{--types}]
3736 [@option{-i}|@option{--no-verbose}]
3737 [@option{-r}|@option{--no-recurse-limit}]
3738 [@option{-R}|@option{--recurse-limit}]
3739 [@option{-s} @var{format}|@option{--format=}@var{format}]
3740 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3741 @c man end
3742 @end smallexample
3743
3744 @c man begin DESCRIPTION cxxfilt
3745
3746 @kindex cxxfilt
3747 The C++ and Java languages provide function overloading, which means
3748 that you can write many functions with the same name, providing that
3749 each function takes parameters of different types. In order to be
3750 able to distinguish these similarly named functions C++ and Java
3751 encode them into a low-level assembler name which uniquely identifies
3752 each different version. This process is known as @dfn{mangling}. The
3753 @command{c++filt}
3754 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3755 MS-DOS this program is named @command{CXXFILT}.}
3756 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3757 names into user-level names so that they can be read.
3758
3759 Every alphanumeric word (consisting of letters, digits, underscores,
3760 dollars, or periods) seen in the input is a potential mangled name.
3761 If the name decodes into a C++ name, the C++ name replaces the
3762 low-level name in the output, otherwise the original word is output.
3763 In this way you can pass an entire assembler source file, containing
3764 mangled names, through @command{c++filt} and see the same source file
3765 containing demangled names.
3766
3767 You can also use @command{c++filt} to decipher individual symbols by
3768 passing them on the command line:
3769
3770 @example
3771 c++filt @var{symbol}
3772 @end example
3773
3774 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3775 names from the standard input instead. All the results are printed on
3776 the standard output. The difference between reading names from the
3777 command line versus reading names from the standard input is that
3778 command-line arguments are expected to be just mangled names and no
3779 checking is performed to separate them from surrounding text. Thus
3780 for example:
3781
3782 @smallexample
3783 c++filt -n _Z1fv
3784 @end smallexample
3785
3786 will work and demangle the name to ``f()'' whereas:
3787
3788 @smallexample
3789 c++filt -n _Z1fv,
3790 @end smallexample
3791
3792 will not work. (Note the extra comma at the end of the mangled
3793 name which makes it invalid). This command however will work:
3794
3795 @smallexample
3796 echo _Z1fv, | c++filt -n
3797 @end smallexample
3798
3799 and will display ``f(),'', i.e., the demangled name followed by a
3800 trailing comma. This behaviour is because when the names are read
3801 from the standard input it is expected that they might be part of an
3802 assembler source file where there might be extra, extraneous
3803 characters trailing after a mangled name. For example:
3804
3805 @smallexample
3806 .type _Z1fv, @@function
3807 @end smallexample
3808
3809 @c man end
3810
3811 @c man begin OPTIONS cxxfilt
3812
3813 @table @env
3814 @item -_
3815 @itemx --strip-underscore
3816 On some systems, both the C and C++ compilers put an underscore in front
3817 of every name. For example, the C name @code{foo} gets the low-level
3818 name @code{_foo}. This option removes the initial underscore. Whether
3819 @command{c++filt} removes the underscore by default is target dependent.
3820
3821 @item -n
3822 @itemx --no-strip-underscore
3823 Do not remove the initial underscore.
3824
3825 @item -p
3826 @itemx --no-params
3827 When demangling the name of a function, do not display the types of
3828 the function's parameters.
3829
3830 @item -t
3831 @itemx --types
3832 Attempt to demangle types as well as function names. This is disabled
3833 by default since mangled types are normally only used internally in
3834 the compiler, and they can be confused with non-mangled names. For example,
3835 a function called ``a'' treated as a mangled type name would be
3836 demangled to ``signed char''.
3837
3838 @item -i
3839 @itemx --no-verbose
3840 Do not include implementation details (if any) in the demangled
3841 output.
3842
3843 @item -r
3844 @itemx -R
3845 @itemx --recurse-limit
3846 @itemx --no-recurse-limit
3847 @itemx --recursion-limit
3848 @itemx --no-recursion-limit
3849 Enables or disables a limit on the amount of recursion performed
3850 whilst demangling strings. Since the name mangling formats allow for
3851 an infinite level of recursion it is possible to create strings whose
3852 decoding will exhaust the amount of stack space available on the host
3853 machine, triggering a memory fault. The limit tries to prevent this
3854 from happening by restricting recursion to 2048 levels of nesting.
3855
3856 The default is for this limit to be enabled, but disabling it may be
3857 necessary in order to demangle truly complicated names. Note however
3858 that if the recursion limit is disabled then stack exhaustion is
3859 possible and any bug reports about such an event will be rejected.
3860
3861 The @option{-r} option is a synonym for the
3862 @option{--no-recurse-limit} option. The @option{-R} option is a
3863 synonym for the @option{--recurse-limit} option.
3864
3865 @item -s @var{format}
3866 @itemx --format=@var{format}
3867 @command{c++filt} can decode various methods of mangling, used by
3868 different compilers. The argument to this option selects which
3869 method it uses:
3870
3871 @table @code
3872 @item auto
3873 Automatic selection based on executable (the default method)
3874 @item gnu
3875 the one used by the @sc{gnu} C++ compiler (g++)
3876 @item lucid
3877 the one used by the Lucid compiler (lcc)
3878 @item arm
3879 the one specified by the C++ Annotated Reference Manual
3880 @item hp
3881 the one used by the HP compiler (aCC)
3882 @item edg
3883 the one used by the EDG compiler
3884 @item gnu-v3
3885 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3886 @item java
3887 the one used by the @sc{gnu} Java compiler (gcj)
3888 @item gnat
3889 the one used by the @sc{gnu} Ada compiler (GNAT).
3890 @end table
3891
3892 @item --help
3893 Print a summary of the options to @command{c++filt} and exit.
3894
3895 @item --version
3896 Print the version number of @command{c++filt} and exit.
3897 @end table
3898
3899 @c man end
3900
3901 @ignore
3902 @c man begin SEEALSO cxxfilt
3903 the Info entries for @file{binutils}.
3904 @c man end
3905 @end ignore
3906
3907 @quotation
3908 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3909 user interface are subject to change in future releases. In particular,
3910 a command-line option may be required in the future to decode a name
3911 passed as an argument on the command line; in other words,
3912
3913 @example
3914 c++filt @var{symbol}
3915 @end example
3916
3917 @noindent
3918 may in a future release become
3919
3920 @example
3921 c++filt @var{option} @var{symbol}
3922 @end example
3923 @end quotation
3924
3925 @node addr2line
3926 @chapter addr2line
3927
3928 @kindex addr2line
3929 @cindex address to file name and line number
3930
3931 @c man title addr2line convert addresses or symbol+offset into file names and line numbers
3932
3933 @smallexample
3934 @c man begin SYNOPSIS addr2line
3935 addr2line [@option{-a}|@option{--addresses}]
3936 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3937 [@option{-C}|@option{--demangle}[=@var{style}]]
3938 [@option{-r}|@option{--no-recurse-limit}]
3939 [@option{-R}|@option{--recurse-limit}]
3940 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3941 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3942 [@option{-i}|@option{--inlines}]
3943 [@option{-p}|@option{--pretty-print}]
3944 [@option{-j}|@option{--section=}@var{name}]
3945 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3946 [addr addr @dots{}]
3947 @c man end
3948 @end smallexample
3949
3950 @c man begin DESCRIPTION addr2line
3951
3952 @command{addr2line} translates addresses or symbol+offset into file names and line numbers.
3953 Given an address or symbol+offset in an executable or an offset in a section of a relocatable
3954 object, it uses the debugging information to figure out which file name and
3955 line number are associated with it.
3956
3957 The executable or relocatable object to use is specified with the @option{-e}
3958 option. The default is the file @file{a.out}. The section in the relocatable
3959 object to use is specified with the @option{-j} option.
3960
3961 @command{addr2line} has two modes of operation.
3962
3963 In the first, hexadecimal addresses or symbol+offset are specified on the command line,
3964 and @command{addr2line} displays the file name and line number for each
3965 address.
3966
3967 In the second, @command{addr2line} reads hexadecimal addresses or symbol+offset from
3968 standard input, and prints the file name and line number for each
3969 address on standard output. In this mode, @command{addr2line} may be used
3970 in a pipe to convert dynamically chosen addresses.
3971
3972 The format of the output is @samp{FILENAME:LINENO}. By default
3973 each input address generates one line of output.
3974
3975 Two options can generate additional lines before each
3976 @samp{FILENAME:LINENO} line (in that order).
3977
3978 If the @option{-a} option is used then a line with the input address
3979 is displayed.
3980
3981 If the @option{-f} option is used, then a line with the
3982 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3983 containing the address.
3984
3985 One option can generate additional lines after the
3986 @samp{FILENAME:LINENO} line.
3987
3988 If the @option{-i} option is used and the code at the given address is
3989 present there because of inlining by the compiler then additional
3990 lines are displayed afterwards. One or two extra lines (if the
3991 @option{-f} option is used) are displayed for each inlined function.
3992
3993 Alternatively if the @option{-p} option is used then each input
3994 address generates a single, long, output line containing the address,
3995 the function name, the file name and the line number. If the
3996 @option{-i} option has also been used then any inlined functions will
3997 be displayed in the same manner, but on separate lines, and prefixed
3998 by the text @samp{(inlined by)}.
3999
4000 If the file name or function name can not be determined,
4001 @command{addr2line} will print two question marks in their place. If the
4002 line number can not be determined, @command{addr2line} will print 0.
4003
4004 When symbol+offset is used, +offset is optional, except when the symbol
4005 is ambigious with a hex number. The resolved symbols can be mangled
4006 or unmangled, except unmangled symbols with + are not allowed.
4007
4008 @c man end
4009
4010 @c man begin OPTIONS addr2line
4011
4012 The long and short forms of options, shown here as alternatives, are
4013 equivalent.
4014
4015 @table @env
4016 @item -a
4017 @itemx --addresses
4018 Display the address before the function name, file and line number
4019 information. The address is printed with a @samp{0x} prefix to easily
4020 identify it.
4021
4022 @item -b @var{bfdname}
4023 @itemx --target=@var{bfdname}
4024 @cindex object code format
4025 Specify that the object-code format for the object files is
4026 @var{bfdname}.
4027
4028 @item -C
4029 @itemx --demangle[=@var{style}]
4030 @cindex demangling in objdump
4031 Decode (@dfn{demangle}) low-level symbol names into user-level names.
4032 Besides removing any initial underscore prepended by the system, this
4033 makes C++ function names readable. Different compilers have different
4034 mangling styles. The optional demangling style argument can be used to
4035 choose an appropriate demangling style for your compiler. @xref{c++filt},
4036 for more information on demangling.
4037
4038 @item -e @var{filename}
4039 @itemx --exe=@var{filename}
4040 Specify the name of the executable for which addresses should be
4041 translated. The default file is @file{a.out}.
4042
4043 @item -f
4044 @itemx --functions
4045 Display function names as well as file and line number information.
4046
4047 @item -s
4048 @itemx --basenames
4049 Display only the base of each file name.
4050
4051 @item -i
4052 @itemx --inlines
4053 If the address belongs to a function that was inlined, the source
4054 information for all enclosing scopes back to the first non-inlined
4055 function will also be printed. For example, if @code{main} inlines
4056 @code{callee1} which inlines @code{callee2}, and address is from
4057 @code{callee2}, the source information for @code{callee1} and @code{main}
4058 will also be printed.
4059
4060 @item -j
4061 @itemx --section
4062 Read offsets relative to the specified section instead of absolute addresses.
4063
4064 @item -p
4065 @itemx --pretty-print
4066 Make the output more human friendly: each location are printed on one line.
4067 If option @option{-i} is specified, lines for all enclosing scopes are
4068 prefixed with @samp{(inlined by)}.
4069
4070 @item -r
4071 @itemx -R
4072 @itemx --recurse-limit
4073 @itemx --no-recurse-limit
4074 @itemx --recursion-limit
4075 @itemx --no-recursion-limit
4076 Enables or disables a limit on the amount of recursion performed
4077 whilst demangling strings. Since the name mangling formats allow for
4078 an infinite level of recursion it is possible to create strings whose
4079 decoding will exhaust the amount of stack space available on the host
4080 machine, triggering a memory fault. The limit tries to prevent this
4081 from happening by restricting recursion to 2048 levels of nesting.
4082
4083 The default is for this limit to be enabled, but disabling it may be
4084 necessary in order to demangle truly complicated names. Note however
4085 that if the recursion limit is disabled then stack exhaustion is
4086 possible and any bug reports about such an event will be rejected.
4087
4088 The @option{-r} option is a synonym for the
4089 @option{--no-recurse-limit} option. The @option{-R} option is a
4090 synonym for the @option{--recurse-limit} option.
4091
4092 Note this option is only effective if the @option{-C} or
4093 @option{--demangle} option has been enabled.
4094
4095 @end table
4096
4097 @c man end
4098
4099 @ignore
4100 @c man begin SEEALSO addr2line
4101 Info entries for @file{binutils}.
4102 @c man end
4103 @end ignore
4104
4105 @node windmc
4106 @chapter windmc
4107
4108 @command{windmc} may be used to generator Windows message resources.
4109
4110 @quotation
4111 @emph{Warning:} @command{windmc} is not always built as part of the binary
4112 utilities, since it is only useful for Windows targets.
4113 @end quotation
4114
4115 @c man title windmc generates Windows message resources
4116
4117 @smallexample
4118 @c man begin SYNOPSIS windmc
4119 windmc [options] input-file
4120 @c man end
4121 @end smallexample
4122
4123 @c man begin DESCRIPTION windmc
4124
4125 @command{windmc} reads message definitions from an input file (.mc) and
4126 translate them into a set of output files. The output files may be of
4127 four kinds:
4128
4129 @table @code
4130 @item h
4131 A C header file containing the message definitions.
4132
4133 @item rc
4134 A resource file compilable by the @command{windres} tool.
4135
4136 @item bin
4137 One or more binary files containing the resource data for a specific
4138 message language.
4139
4140 @item dbg
4141 A C include file that maps message id's to their symbolic name.
4142 @end table
4143
4144 The exact description of these different formats is available in
4145 documentation from Microsoft.
4146
4147 When @command{windmc} converts from the @code{mc} format to the @code{bin}
4148 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
4149 Windows Message Compiler.
4150
4151 @c man end
4152
4153 @c man begin OPTIONS windmc
4154
4155 @table @env
4156 @item -a
4157 @itemx --ascii_in
4158 Specifies that the input file specified is ASCII. This is the default
4159 behaviour.
4160
4161 @item -A
4162 @itemx --ascii_out
4163 Specifies that messages in the output @code{bin} files should be in ASCII
4164 format.
4165
4166 @item -b
4167 @itemx --binprefix
4168 Specifies that @code{bin} filenames should have to be prefixed by the
4169 basename of the source file.
4170
4171 @item -c
4172 @itemx --customflag
4173 Sets the customer bit in all message id's.
4174
4175 @item -C @var{codepage}
4176 @itemx --codepage_in @var{codepage}
4177 Sets the default codepage to be used to convert input file to UTF16. The
4178 default is ocdepage 1252.
4179
4180 @item -d
4181 @itemx --decimal_values
4182 Outputs the constants in the header file in decimal. Default is using
4183 hexadecimal output.
4184
4185 @item -e @var{ext}
4186 @itemx --extension @var{ext}
4187 The extension for the header file. The default is .h extension.
4188
4189 @item -F @var{target}
4190 @itemx --target @var{target}
4191 Specify the BFD format to use for a bin file as output. This
4192 is a BFD target name; you can use the @option{--help} option to see a list
4193 of supported targets. Normally @command{windmc} will use the default
4194 format, which is the first one listed by the @option{--help} option.
4195 @ifclear man
4196 @ref{Target Selection}.
4197 @end ifclear
4198
4199 @item -h @var{path}
4200 @itemx --headerdir @var{path}
4201 The target directory of the generated header file. The default is the
4202 current directory.
4203
4204 @item -H
4205 @itemx --help
4206 Displays a list of command-line options and then exits.
4207
4208 @item -m @var{characters}
4209 @itemx --maxlength @var{characters}
4210 Instructs @command{windmc} to generate a warning if the length
4211 of any message exceeds the number specified.
4212
4213 @item -n
4214 @itemx --nullterminate
4215 Terminate message text in @code{bin} files by zero. By default they are
4216 terminated by CR/LF.
4217
4218 @item -o
4219 @itemx --hresult_use
4220 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4221 file, using HRESULT definitions. Status codes are used if the flag is not
4222 specified.
4223
4224 @item -O @var{codepage}
4225 @itemx --codepage_out @var{codepage}
4226 Sets the default codepage to be used to output text files. The default
4227 is ocdepage 1252.
4228
4229 @item -r @var{path}
4230 @itemx --rcdir @var{path}
4231 The target directory for the generated @code{rc} script and the generated
4232 @code{bin} files that the resource compiler script includes. The default
4233 is the current directory.
4234
4235 @item -u
4236 @itemx --unicode_in
4237 Specifies that the input file is UTF16.
4238
4239 @item -U
4240 @itemx --unicode_out
4241 Specifies that messages in the output @code{bin} file should be in UTF16
4242 format. This is the default behaviour.
4243
4244 @item -v
4245 @item --verbose
4246 Enable verbose mode.
4247
4248 @item -V
4249 @item --version
4250 Prints the version number for @command{windmc}.
4251
4252 @item -x @var{path}
4253 @itemx --xdgb @var{path}
4254 The path of the @code{dbg} C include file that maps message id's to the
4255 symbolic name. No such file is generated without specifying the switch.
4256 @end table
4257
4258 @c man end
4259
4260 @ignore
4261 @c man begin SEEALSO windmc
4262 the Info entries for @file{binutils}.
4263 @c man end
4264 @end ignore
4265
4266 @node windres
4267 @chapter windres
4268
4269 @command{windres} may be used to manipulate Windows resources.
4270
4271 @quotation
4272 @emph{Warning:} @command{windres} is not always built as part of the binary
4273 utilities, since it is only useful for Windows targets.
4274 @end quotation
4275
4276 @c man title windres manipulate Windows resources
4277
4278 @smallexample
4279 @c man begin SYNOPSIS windres
4280 windres [options] [input-file] [output-file]
4281 @c man end
4282 @end smallexample
4283
4284 @c man begin DESCRIPTION windres
4285
4286 @command{windres} reads resources from an input file and copies them into
4287 an output file. Either file may be in one of three formats:
4288
4289 @table @code
4290 @item rc
4291 A text format read by the Resource Compiler.
4292
4293 @item res
4294 A binary format generated by the Resource Compiler.
4295
4296 @item coff
4297 A COFF object or executable.
4298 @end table
4299
4300 The exact description of these different formats is available in
4301 documentation from Microsoft.
4302
4303 When @command{windres} converts from the @code{rc} format to the @code{res}
4304 format, it is acting like the Windows Resource Compiler. When
4305 @command{windres} converts from the @code{res} format to the @code{coff}
4306 format, it is acting like the Windows @code{CVTRES} program.
4307
4308 When @command{windres} generates an @code{rc} file, the output is similar
4309 but not identical to the format expected for the input. When an input
4310 @code{rc} file refers to an external filename, an output @code{rc} file
4311 will instead include the file contents.
4312
4313 If the input or output format is not specified, @command{windres} will
4314 guess based on the file name, or, for the input file, the file contents.
4315 A file with an extension of @file{.rc} will be treated as an @code{rc}
4316 file, a file with an extension of @file{.res} will be treated as a
4317 @code{res} file, and a file with an extension of @file{.o} or
4318 @file{.exe} will be treated as a @code{coff} file.
4319
4320 If no output file is specified, @command{windres} will print the resources
4321 in @code{rc} format to standard output.
4322
4323 The normal use is for you to write an @code{rc} file, use @command{windres}
4324 to convert it to a COFF object file, and then link the COFF file into
4325 your application. This will make the resources described in the
4326 @code{rc} file available to Windows.
4327
4328 @c man end
4329
4330 @c man begin OPTIONS windres
4331
4332 @table @env
4333 @item -i @var{filename}
4334 @itemx --input @var{filename}
4335 The name of the input file. If this option is not used, then
4336 @command{windres} will use the first non-option argument as the input file
4337 name. If there are no non-option arguments, then @command{windres} will
4338 read from standard input. @command{windres} can not read a COFF file from
4339 standard input.
4340
4341 @item -o @var{filename}
4342 @itemx --output @var{filename}
4343 The name of the output file. If this option is not used, then
4344 @command{windres} will use the first non-option argument, after any used
4345 for the input file name, as the output file name. If there is no
4346 non-option argument, then @command{windres} will write to standard output.
4347 @command{windres} can not write a COFF file to standard output. Note,
4348 for compatibility with @command{rc} the option @option{-fo} is also
4349 accepted, but its use is not recommended.
4350
4351 @item -J @var{format}
4352 @itemx --input-format @var{format}
4353 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4354 @samp{coff}. If no input format is specified, @command{windres} will
4355 guess, as described above.
4356
4357 @item -O @var{format}
4358 @itemx --output-format @var{format}
4359 The output format to generate. @var{format} may be @samp{res},
4360 @samp{rc}, or @samp{coff}. If no output format is specified,
4361 @command{windres} will guess, as described above.
4362
4363 @item -F @var{target}
4364 @itemx --target @var{target}
4365 Specify the BFD format to use for a COFF file as input or output. This
4366 is a BFD target name; you can use the @option{--help} option to see a list
4367 of supported targets. Normally @command{windres} will use the default
4368 format, which is the first one listed by the @option{--help} option.
4369 @ifclear man
4370 @ref{Target Selection}.
4371 @end ifclear
4372
4373 @item --preprocessor @var{program}
4374 When @command{windres} reads an @code{rc} file, it runs it through the C
4375 preprocessor first. This option may be used to specify the preprocessor
4376 to use. The default preprocessor is @code{gcc}.
4377
4378 @item --preprocessor-arg @var{option}
4379 When @command{windres} reads an @code{rc} file, it runs it through
4380 the C preprocessor first. This option may be used to specify additional
4381 text to be passed to preprocessor on its command line.
4382 This option can be used multiple times to add multiple options to the
4383 preprocessor command line.
4384 If the @option{--preprocessor} option has not been specified then a
4385 default set of preprocessor arguments will be used, with any
4386 @option{--preprocessor-arg} options being placed after them on the
4387 command line. These default arguments are @code{-E},
4388 @code{-xc-header} and @code{-DRC_INVOKED}.
4389
4390 @item -I @var{directory}
4391 @itemx --include-dir @var{directory}
4392 Specify an include directory to use when reading an @code{rc} file.
4393 @command{windres} will pass this to the preprocessor as an @option{-I}
4394 option. @command{windres} will also search this directory when looking for
4395 files named in the @code{rc} file. If the argument passed to this command
4396 matches any of the supported @var{formats} (as described in the @option{-J}
4397 option), it will issue a deprecation warning, and behave just like the
4398 @option{-J} option. New programs should not use this behaviour. If a
4399 directory happens to match a @var{format}, simple prefix it with @samp{./}
4400 to disable the backward compatibility.
4401
4402 @item -D @var{target}
4403 @itemx --define @var{sym}[=@var{val}]
4404 Specify a @option{-D} option to pass to the preprocessor when reading an
4405 @code{rc} file.
4406
4407 @item -U @var{target}
4408 @itemx --undefine @var{sym}
4409 Specify a @option{-U} option to pass to the preprocessor when reading an
4410 @code{rc} file.
4411
4412 @item -r
4413 Ignored for compatibility with rc.
4414
4415 @item -v
4416 Enable verbose mode. This tells you what the preprocessor is if you
4417 didn't specify one.
4418
4419 @item -c @var{val}
4420 @item --codepage @var{val}
4421 Specify the default codepage to use when reading an @code{rc} file.
4422 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4423 codepage code. The valid range is from zero up to 0xffff, but the
4424 validity of the codepage is host and configuration dependent.
4425
4426 @item -l @var{val}
4427 @item --language @var{val}
4428 Specify the default language to use when reading an @code{rc} file.
4429 @var{val} should be a hexadecimal language code. The low eight bits are
4430 the language, and the high eight bits are the sublanguage.
4431
4432 @item --use-temp-file
4433 Use a temporary file to instead of using popen to read the output of
4434 the preprocessor. Use this option if the popen implementation is buggy
4435 on the host (eg., certain non-English language versions of Windows 95 and
4436 Windows 98 are known to have buggy popen where the output will instead
4437 go the console).
4438
4439 @item --no-use-temp-file
4440 Use popen, not a temporary file, to read the output of the preprocessor.
4441 This is the default behaviour.
4442
4443 @item -h
4444 @item --help
4445 Prints a usage summary.
4446
4447 @item -V
4448 @item --version
4449 Prints the version number for @command{windres}.
4450
4451 @item --yydebug
4452 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4453 this will turn on parser debugging.
4454 @end table
4455
4456 @c man end
4457
4458 @ignore
4459 @c man begin SEEALSO windres
4460 the Info entries for @file{binutils}.
4461 @c man end
4462 @end ignore
4463
4464 @node dlltool
4465 @chapter dlltool
4466 @cindex DLL
4467 @kindex dlltool
4468
4469 @command{dlltool} is used to create the files needed to create dynamic
4470 link libraries (DLLs) on systems which understand PE format image
4471 files such as Windows. A DLL contains an export table which contains
4472 information that the runtime loader needs to resolve references from a
4473 referencing program.
4474
4475 The export table is generated by this program by reading in a
4476 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4477 will be in the DLL. A @file{.o} file can contain information in
4478 special @samp{.drectve} sections with export information.
4479
4480 @quotation
4481 @emph{Note:} @command{dlltool} is not always built as part of the
4482 binary utilities, since it is only useful for those targets which
4483 support DLLs.
4484 @end quotation
4485
4486 @c man title dlltool create files needed to build and use DLLs
4487
4488 @smallexample
4489 @c man begin SYNOPSIS dlltool
4490 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4491 [@option{-b}|@option{--base-file} @var{base-file-name}]
4492 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4493 [@option{-z}|@option{--output-def} @var{def-file-name}]
4494 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4495 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4496 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4497 [@option{--exclude-symbols} @var{list}]
4498 [@option{--no-default-excludes}]
4499 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4500 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4501 [@option{-a}|@option{--add-indirect}]
4502 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4503 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4504 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4505 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4506 [@option{--use-nul-prefixed-import-tables}]
4507 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4508 [@option{-i}|@option{--interwork}]
4509 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4510 [@option{-v}|@option{--verbose}]
4511 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4512 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4513 [@option{--deterministic-libraries}] [@option{--non-deterministic-libraries}]
4514 [object-file @dots{}]
4515 @c man end
4516 @end smallexample
4517
4518 @c man begin DESCRIPTION dlltool
4519
4520 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4521 @option{-b} options as well as object files specified on the command
4522 line. It then processes these inputs and if the @option{-e} option has
4523 been specified it creates a exports file. If the @option{-l} option
4524 has been specified it creates a library file and if the @option{-z} option
4525 has been specified it creates a def file. Any or all of the @option{-e},
4526 @option{-l} and @option{-z} options can be present in one invocation of
4527 dlltool.
4528
4529 When creating a DLL, along with the source for the DLL, it is necessary
4530 to have three other files. @command{dlltool} can help with the creation of
4531 these files.
4532
4533 The first file is a @file{.def} file which specifies which functions are
4534 exported from the DLL, which functions the DLL imports, and so on. This
4535 is a text file and can be created by hand, or @command{dlltool} can be used
4536 to create it using the @option{-z} option. In this case @command{dlltool}
4537 will scan the object files specified on its command line looking for
4538 those functions which have been specially marked as being exported and
4539 put entries for them in the @file{.def} file it creates.
4540
4541 In order to mark a function as being exported from a DLL, it needs to
4542 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4543 section of the object file. This can be done in C by using the
4544 asm() operator:
4545
4546 @smallexample
4547 asm (".section .drectve");
4548 asm (".ascii \"-export:my_func\"");
4549
4550 int my_func (void) @{ @dots{} @}
4551 @end smallexample
4552
4553 The second file needed for DLL creation is an exports file. This file
4554 is linked with the object files that make up the body of the DLL and it
4555 handles the interface between the DLL and the outside world. This is a
4556 binary file and it can be created by giving the @option{-e} option to
4557 @command{dlltool} when it is creating or reading in a @file{.def} file.
4558
4559 The third file needed for DLL creation is the library file that programs
4560 will link with in order to access the functions in the DLL (an `import
4561 library'). This file can be created by giving the @option{-l} option to
4562 dlltool when it is creating or reading in a @file{.def} file.
4563
4564 If the @option{-y} option is specified, dlltool generates a delay-import
4565 library that can be used instead of the normal import library to allow
4566 a program to link to the dll only as soon as an imported function is
4567 called for the first time. The resulting executable will need to be
4568 linked to the static delayimp library containing __delayLoadHelper2(),
4569 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4570
4571 @command{dlltool} builds the library file by hand, but it builds the
4572 exports file by creating temporary files containing assembler statements
4573 and then assembling these. The @option{-S} command-line option can be
4574 used to specify the path to the assembler that dlltool will use,
4575 and the @option{-f} option can be used to pass specific flags to that
4576 assembler. The @option{-n} can be used to prevent dlltool from deleting
4577 these temporary assembler files when it is done, and if @option{-n} is
4578 specified twice then this will prevent dlltool from deleting the
4579 temporary object files it used to build the library.
4580
4581 Here is an example of creating a DLL from a source file @samp{dll.c} and
4582 also creating a program (from an object file called @samp{program.o})
4583 that uses that DLL:
4584
4585 @smallexample
4586 gcc -c dll.c
4587 dlltool -e exports.o -l dll.lib dll.o
4588 gcc dll.o exports.o -o dll.dll
4589 gcc program.o dll.lib -o program
4590 @end smallexample
4591
4592
4593 @command{dlltool} may also be used to query an existing import library
4594 to determine the name of the DLL to which it is associated. See the
4595 description of the @option{-I} or @option{--identify} option.
4596
4597 @c man end
4598
4599 @c man begin OPTIONS dlltool
4600
4601 The command-line options have the following meanings:
4602
4603 @table @env
4604
4605 @item -d @var{filename}
4606 @itemx --input-def @var{filename}
4607 @cindex input .def file
4608 Specifies the name of a @file{.def} file to be read in and processed.
4609
4610 @item -b @var{filename}
4611 @itemx --base-file @var{filename}
4612 @cindex base files
4613 Specifies the name of a base file to be read in and processed. The
4614 contents of this file will be added to the relocation section in the
4615 exports file generated by dlltool.
4616
4617 @item -e @var{filename}
4618 @itemx --output-exp @var{filename}
4619 Specifies the name of the export file to be created by dlltool.
4620
4621 @item -z @var{filename}
4622 @itemx --output-def @var{filename}
4623 Specifies the name of the @file{.def} file to be created by dlltool.
4624
4625 @item -l @var{filename}
4626 @itemx --output-lib @var{filename}
4627 Specifies the name of the library file to be created by dlltool.
4628
4629 @item -y @var{filename}
4630 @itemx --output-delaylib @var{filename}
4631 Specifies the name of the delay-import library file to be created by dlltool.
4632
4633 @item --deterministic-libraries
4634 @itemx --non-deterministic-libraries
4635 When creating output libraries in response to either the
4636 @option{--output-lib} or @option{--output-delaylib} options either use
4637 the value of zero for any timestamps, user ids and group ids created
4638 (@option{--deterministic-libraries}) or the actual timestamps, user
4639 ids and group ids (@option{--non-deterministic-libraries}).
4640
4641 @item --export-all-symbols
4642 Treat all global and weak defined symbols found in the input object
4643 files as symbols to be exported. There is a small list of symbols which
4644 are not exported by default; see the @option{--no-default-excludes}
4645 option. You may add to the list of symbols to not export by using the
4646 @option{--exclude-symbols} option.
4647
4648 @item --no-export-all-symbols
4649 Only export symbols explicitly listed in an input @file{.def} file or in
4650 @samp{.drectve} sections in the input object files. This is the default
4651 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4652 attributes in the source code.
4653
4654 @item --exclude-symbols @var{list}
4655 Do not export the symbols in @var{list}. This is a list of symbol names
4656 separated by comma or colon characters. The symbol names should not
4657 contain a leading underscore. This is only meaningful when
4658 @option{--export-all-symbols} is used.
4659
4660 @item --no-default-excludes
4661 When @option{--export-all-symbols} is used, it will by default avoid
4662 exporting certain special symbols. The current list of symbols to avoid
4663 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4664 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4665 to go ahead and export these special symbols. This is only meaningful
4666 when @option{--export-all-symbols} is used.
4667
4668 @item -S @var{path}
4669 @itemx --as @var{path}
4670 Specifies the path, including the filename, of the assembler to be used
4671 to create the exports file.
4672
4673 @item -f @var{options}
4674 @itemx --as-flags @var{options}
4675 Specifies any specific command-line options to be passed to the
4676 assembler when building the exports file. This option will work even if
4677 the @option{-S} option is not used. This option only takes one argument,
4678 and if it occurs more than once on the command line, then later
4679 occurrences will override earlier occurrences. So if it is necessary to
4680 pass multiple options to the assembler they should be enclosed in
4681 double quotes.
4682
4683 @item -D @var{name}
4684 @itemx --dll-name @var{name}
4685 Specifies the name to be stored in the @file{.def} file as the name of
4686 the DLL when the @option{-e} option is used. If this option is not
4687 present, then the filename given to the @option{-e} option will be
4688 used as the name of the DLL.
4689
4690 @item -m @var{machine}
4691 @itemx -machine @var{machine}
4692 Specifies the type of machine for which the library file should be
4693 built. @command{dlltool} has a built in default type, depending upon how
4694 it was created, but this option can be used to override that. This is
4695 normally only useful when creating DLLs for an ARM processor, when the
4696 contents of the DLL are actually encode using Thumb instructions.
4697
4698 @item -a
4699 @itemx --add-indirect
4700 Specifies that when @command{dlltool} is creating the exports file it
4701 should add a section which allows the exported functions to be
4702 referenced without using the import library. Whatever the hell that
4703 means!
4704
4705 @item -U
4706 @itemx --add-underscore
4707 Specifies that when @command{dlltool} is creating the exports file it
4708 should prepend an underscore to the names of @emph{all} exported symbols.
4709
4710 @item --no-leading-underscore
4711 @item --leading-underscore
4712 Specifies whether standard symbol should be forced to be prefixed, or
4713 not.
4714
4715 @item --add-stdcall-underscore
4716 Specifies that when @command{dlltool} is creating the exports file it
4717 should prepend an underscore to the names of exported @emph{stdcall}
4718 functions. Variable names and non-stdcall function names are not modified.
4719 This option is useful when creating GNU-compatible import libs for third
4720 party DLLs that were built with MS-Windows tools.
4721
4722 @item -k
4723 @itemx --kill-at
4724 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4725 of stdcall functions that will be imported from the DLL. This is
4726 useful when creating an import library for a DLL which exports stdcall
4727 functions but without the usual @samp{@@<number>} symbol name suffix.
4728
4729 This does not change the naming of symbols provided by the import library
4730 to programs linked against it, but only the entries in the import table
4731 (ie the .idata section).
4732
4733 @item -A
4734 @itemx --add-stdcall-alias
4735 Specifies that when @command{dlltool} is creating the exports file it
4736 should add aliases for stdcall symbols without @samp{@@ <number>}
4737 in addition to the symbols with @samp{@@ <number>}.
4738
4739 @item -p
4740 @itemx --ext-prefix-alias @var{prefix}
4741 Causes @command{dlltool} to create external aliases for all DLL
4742 imports with the specified prefix. The aliases are created for both
4743 external and import symbols with no leading underscore.
4744
4745 @item -x
4746 @itemx --no-idata4
4747 Specifies that when @command{dlltool} is creating the exports and library
4748 files it should omit the @code{.idata4} section. This is for compatibility
4749 with certain operating systems.
4750
4751 @item --use-nul-prefixed-import-tables
4752 Specifies that when @command{dlltool} is creating the exports and library
4753 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4754 element. This emulates old gnu import library generation of
4755 @code{dlltool}. By default this option is turned off.
4756
4757 @item -c
4758 @itemx --no-idata5
4759 Specifies that when @command{dlltool} is creating the exports and library
4760 files it should omit the @code{.idata5} section. This is for compatibility
4761 with certain operating systems.
4762
4763 @item -I @var{filename}
4764 @itemx --identify @var{filename}
4765 Specifies that @command{dlltool} should inspect the import library
4766 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4767 of the associated DLL(s). This can be performed in addition to any
4768 other operations indicated by the other options and arguments.
4769 @command{dlltool} fails if the import library does not exist or is not
4770 actually an import library. See also @option{--identify-strict}.
4771
4772 @item --identify-strict
4773 Modifies the behavior of the @option{--identify} option, such
4774 that an error is reported if @var{filename} is associated with
4775 more than one DLL.
4776
4777 @item -i
4778 @itemx --interwork
4779 Specifies that @command{dlltool} should mark the objects in the library
4780 file and exports file that it produces as supporting interworking
4781 between ARM and Thumb code.
4782
4783 @item -n
4784 @itemx --nodelete
4785 Makes @command{dlltool} preserve the temporary assembler files it used to
4786 create the exports file. If this option is repeated then dlltool will
4787 also preserve the temporary object files it uses to create the library
4788 file.
4789
4790 @item -t @var{prefix}
4791 @itemx --temp-prefix @var{prefix}
4792 Makes @command{dlltool} use @var{prefix} when constructing the names of
4793 temporary assembler and object files. By default, the temp file prefix
4794 is generated from the pid.
4795
4796 @item -v
4797 @itemx --verbose
4798 Make dlltool describe what it is doing.
4799
4800 @item -h
4801 @itemx --help
4802 Displays a list of command-line options and then exits.
4803
4804 @item -V
4805 @itemx --version
4806 Displays dlltool's version number and then exits.
4807
4808 @end table
4809
4810 @c man end
4811
4812 @menu
4813 * def file format:: The format of the dlltool @file{.def} file
4814 @end menu
4815
4816 @node def file format
4817 @section The format of the @command{dlltool} @file{.def} file
4818
4819 A @file{.def} file contains any number of the following commands:
4820
4821 @table @asis
4822
4823 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4824 The result is going to be named @var{name}@code{.exe}.
4825
4826 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4827 The result is going to be named @var{name}@code{.dll}.
4828 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4829 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4830 details).
4831
4832 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4833 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4834 Declares @var{name1} as an exported symbol from the DLL, with optional
4835 ordinal number @var{integer}, or declares @var{name1} as an alias
4836 (forward) of the function @var{external-name} in the DLL.
4837 If @var{its_name} is specified, this name is used as string in export table.
4838 @var{module-name}.
4839 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4840 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4841 If you want to use LIBRARY as name then you need to quote it.
4842
4843 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) [ == ) @var{its_name} @code{]} *}
4844 Declares that @var{external-name} or the exported function whose
4845 ordinal number is @var{integer} is to be imported from the file
4846 @var{module-name}. If @var{internal-name} is specified then this is
4847 the name that the imported function will be referred to in the body of
4848 the DLL.
4849 If @var{its_name} is specified, this name is used as string in import table.
4850 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4851 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4852 If you want to use LIBRARY as name then you need to quote it.
4853
4854 @item @code{DESCRIPTION} @var{string}
4855 Puts @var{string} into the output @file{.exp} file in the
4856 @code{.rdata} section.
4857
4858 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4859 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4860 Generates @code{--stack} or @code{--heap}
4861 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4862 section. The linker will see this and act upon it.
4863
4864 @item @code{CODE} @var{attr} @code{+}
4865 @item @code{DATA} @var{attr} @code{+}
4866 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4867 Generates @code{--attr} @var{section-name} @var{attr} in the output
4868 @code{.drectve} section, where @var{attr} is one of @code{READ},
4869 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4870 this and act upon it.
4871
4872 @end table
4873
4874 @ignore
4875 @c man begin SEEALSO dlltool
4876 The Info pages for @file{binutils}.
4877 @c man end
4878 @end ignore
4879
4880 @node readelf
4881 @chapter readelf
4882
4883 @cindex ELF file information
4884 @kindex readelf
4885
4886 @c man title readelf display information about ELF files
4887
4888 @smallexample
4889 @c man begin SYNOPSIS readelf
4890 readelf [@option{-a}|@option{--all}]
4891 [@option{-h}|@option{--file-header}]
4892 [@option{-l}|@option{--program-headers}|@option{--segments}]
4893 [@option{-S}|@option{--section-headers}|@option{--sections}]
4894 [@option{-g}|@option{--section-groups}]
4895 [@option{-t}|@option{--section-details}]
4896 [@option{-e}|@option{--headers}]
4897 [@option{-s}|@option{--syms}|@option{--symbols}]
4898 [@option{--dyn-syms}|@option{--lto-syms}]
4899 [@option{--sym-base=[0|8|10|16]}]
4900 [@option{--demangle@var{=style}}|@option{--no-demangle}]
4901 [@option{--quiet}]
4902 [@option{--recurse-limit}|@option{--no-recurse-limit}]
4903 [@option{-U} @var{method}|@option{--unicode=}@var{method}]
4904 [@option{-n}|@option{--notes}]
4905 [@option{-r}|@option{--relocs}]
4906 [@option{-u}|@option{--unwind}]
4907 [@option{-d}|@option{--dynamic}]
4908 [@option{-V}|@option{--version-info}]
4909 [@option{-A}|@option{--arch-specific}]
4910 [@option{-D}|@option{--use-dynamic}]
4911 [@option{-L}|@option{--lint}|@option{--enable-checks}]
4912 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4913 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4914 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4915 [@option{-z}|@option{--decompress}]
4916 [@option{-c}|@option{--archive-index}]
4917 [@option{-w[lLiaprmfFsoORtUuTgAck]}|
4918 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
4919 [@option{-wK}|@option{--debug-dump=follow-links}]
4920 [@option{-wN}|@option{--debug-dump=no-follow-links}]
4921 [@option{-wD}|@option{--debug-dump=use-debuginfod}]
4922 [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
4923 [@option{-P}|@option{--process-links}]
4924 [@option{--dwarf-depth=@var{n}}]
4925 [@option{--dwarf-start=@var{n}}]
4926 [@option{--ctf=}@var{section}]
4927 [@option{--ctf-parent=}@var{section}]
4928 [@option{--ctf-symbols=}@var{section}]
4929 [@option{--ctf-strings=}@var{section}]
4930 [@option{-I}|@option{--histogram}]
4931 [@option{-v}|@option{--version}]
4932 [@option{-W}|@option{--wide}]
4933 [@option{-T}|@option{--silent-truncation}]
4934 [@option{-H}|@option{--help}]
4935 @var{elffile}@dots{}
4936 @c man end
4937 @end smallexample
4938
4939 @c man begin DESCRIPTION readelf
4940
4941 @command{readelf} displays information about one or more ELF format object
4942 files. The options control what particular information to display.
4943
4944 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4945 64-bit ELF files are supported, as are archives containing ELF files.
4946
4947 This program performs a similar function to @command{objdump} but it
4948 goes into more detail and it exists independently of the @sc{bfd}
4949 library, so if there is a bug in @sc{bfd} then readelf will not be
4950 affected.
4951
4952 @c man end
4953
4954 @c man begin OPTIONS readelf
4955
4956 The long and short forms of options, shown here as alternatives, are
4957 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4958 given.
4959
4960 @table @env
4961 @item -a
4962 @itemx --all
4963 Equivalent to specifying @option{--file-header},
4964 @option{--program-headers}, @option{--sections}, @option{--symbols},
4965 @option{--relocs}, @option{--dynamic}, @option{--notes},
4966 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4967 @option{--section-groups} and @option{--histogram}.
4968
4969 Note - this option does not enable @option{--use-dynamic} itself, so
4970 if that option is not present on the command line then dynamic symbols
4971 and dynamic relocs will not be displayed.
4972
4973 @item -h
4974 @itemx --file-header
4975 @cindex ELF file header information
4976 Displays the information contained in the ELF header at the start of the
4977 file.
4978
4979 @item -l
4980 @itemx --program-headers
4981 @itemx --segments
4982 @cindex ELF program header information
4983 @cindex ELF segment information
4984 Displays the information contained in the file's segment headers, if it
4985 has any.
4986
4987 @item --quiet
4988 @cindex quiet
4989 Suppress "no symbols" diagnostic.
4990
4991 @item -S
4992 @itemx --sections
4993 @itemx --section-headers
4994 @cindex ELF section information
4995 Displays the information contained in the file's section headers, if it
4996 has any.
4997
4998 @item -g
4999 @itemx --section-groups
5000 @cindex ELF section group information
5001 Displays the information contained in the file's section groups, if it
5002 has any.
5003
5004 @item -t
5005 @itemx --section-details
5006 @cindex ELF section information
5007 Displays the detailed section information. Implies @option{-S}.
5008
5009 @item -s
5010 @itemx --symbols
5011 @itemx --syms
5012 @cindex ELF symbol table information
5013 Displays the entries in symbol table section of the file, if it has one.
5014 If a symbol has version information associated with it then this is
5015 displayed as well. The version string is displayed as a suffix to the
5016 symbol name, preceded by an @@ character. For example
5017 @samp{foo@@VER_1}. If the version is the default version to be used
5018 when resolving unversioned references to the symbol then it is
5019 displayed as a suffix preceded by two @@ characters. For example
5020 @samp{foo@@@@VER_2}.
5021
5022 @item --dyn-syms
5023 @cindex ELF dynamic symbol table information
5024 Displays the entries in dynamic symbol table section of the file, if it
5025 has one. The output format is the same as the format used by the
5026 @option{--syms} option.
5027
5028 @item --lto-syms
5029 @cindex LTO symbol table
5030 Displays the contents of any LTO symbol tables in the file.
5031
5032 @item --sym-base=[0|8|10|16]
5033 @cindex symbol table size base
5034 Forces the size field of the symbol table to use the given base. Any
5035 unrecognized options will be treated as @samp{0}. @option{--sym-base=0}
5036 represents the default and legacy behaviour. This will output sizes as decimal
5037 for numbers less than 100000. For sizes 100000 and greater hexadecimal notation
5038 will be used with a 0x prefix.
5039 @option{--sym-base=8} will give the symbol sizes in octal.
5040 @option{--sym-base=10} will always give the symbol sizes in decimal.
5041 @option{--sym-base=16} will always give the symbol sizes in hexadecimal with a
5042 0x prefix.
5043
5044 @item -C
5045 @itemx --demangle[=@var{style}]
5046 @cindex demangling in nm
5047 Decode (@dfn{demangle}) low-level symbol names into user-level names.
5048 This makes C++ function names readable. Different compilers have
5049 different mangling styles. The optional demangling style argument can
5050 be used to choose an appropriate demangling style for your
5051 compiler. @xref{c++filt}, for more information on demangling.
5052
5053 @item --no-demangle
5054 Do not demangle low-level symbol names. This is the default.
5055
5056 @item --recurse-limit
5057 @itemx --no-recurse-limit
5058 @itemx --recursion-limit
5059 @itemx --no-recursion-limit
5060 Enables or disables a limit on the amount of recursion performed
5061 whilst demangling strings. Since the name mangling formats allow for
5062 an infinite level of recursion it is possible to create strings whose
5063 decoding will exhaust the amount of stack space available on the host
5064 machine, triggering a memory fault. The limit tries to prevent this
5065 from happening by restricting recursion to 2048 levels of nesting.
5066
5067 The default is for this limit to be enabled, but disabling it may be
5068 necessary in order to demangle truly complicated names. Note however
5069 that if the recursion limit is disabled then stack exhaustion is
5070 possible and any bug reports about such an event will be rejected.
5071
5072 @item -U @var{[d|i|l|e|x|h]}
5073 @itemx --unicode=[default|invalid|locale|escape|hex|highlight]
5074 Controls the display of non-ASCII characters in identifier names.
5075 The default (@option{--unicode=locale} or @option{--unicode=default}) is
5076 to treat them as multibyte characters and display them in the current
5077 locale. All other versions of this option treat the bytes as UTF-8
5078 encoded values and attempt to interpret them. If they cannot be
5079 interpreted or if the @option{--unicode=invalid} option is used then
5080 they are displayed as a sequence of hex bytes, encloses in curly
5081 parethesis characters.
5082
5083 Using the @option{--unicode=escape} option will display the characters
5084 as as unicode escape sequences (@var{\uxxxx}). Using the
5085 @option{--unicode=hex} will display the characters as hex byte
5086 sequences enclosed between angle brackets.
5087
5088 Using the @option{--unicode=highlight} will display the characters as
5089 unicode escape sequences but it will also highlighted them in red,
5090 assuming that colouring is supported by the output device. The
5091 colouring is intended to draw attention to the presence of unicode
5092 sequences when they might not be expected.
5093
5094 @item -e
5095 @itemx --headers
5096 Display all the headers in the file. Equivalent to @option{-h -l -S}.
5097
5098 @item -n
5099 @itemx --notes
5100 @cindex ELF notes
5101 Displays the contents of the NOTE segments and/or sections, if any.
5102
5103 @item -r
5104 @itemx --relocs
5105 @cindex ELF reloc information
5106 Displays the contents of the file's relocation section, if it has one.
5107
5108 @item -u
5109 @itemx --unwind
5110 @cindex unwind information
5111 Displays the contents of the file's unwind section, if it has one. Only
5112 the unwind sections for IA64 ELF files, as well as ARM unwind tables
5113 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
5114 support is not yet implemented for your architecture you could try
5115 dumping the contents of the @var{.eh_frames} section using the
5116 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
5117 options.
5118
5119 @item -d
5120 @itemx --dynamic
5121 @cindex ELF dynamic section information
5122 Displays the contents of the file's dynamic section, if it has one.
5123
5124 @item -V
5125 @itemx --version-info
5126 @cindex ELF version sections information
5127 Displays the contents of the version sections in the file, it they
5128 exist.
5129
5130 @item -A
5131 @itemx --arch-specific
5132 Displays architecture-specific information in the file, if there
5133 is any.
5134
5135 @item -D
5136 @itemx --use-dynamic
5137 When displaying symbols, this option makes @command{readelf} use the
5138 symbol hash tables in the file's dynamic section, rather than the
5139 symbol table sections.
5140
5141 When displaying relocations, this option makes @command{readelf}
5142 display the dynamic relocations rather than the static relocations.
5143
5144 @item -L
5145 @itemx --lint
5146 @itemx --enable-checks
5147 Displays warning messages about possible problems with the file(s)
5148 being examined. If used on its own then all of the contents of the
5149 file(s) will be examined. If used with one of the dumping options
5150 then the warning messages will only be produced for the things being
5151 displayed.
5152
5153 @item -x <number or name>
5154 @itemx --hex-dump=<number or name>
5155 Displays the contents of the indicated section as a hexadecimal bytes.
5156 A number identifies a particular section by index in the section table;
5157 any other string identifies all sections with that name in the object file.
5158
5159 @item -R <number or name>
5160 @itemx --relocated-dump=<number or name>
5161 Displays the contents of the indicated section as a hexadecimal
5162 bytes. A number identifies a particular section by index in the
5163 section table; any other string identifies all sections with that name
5164 in the object file. The contents of the section will be relocated
5165 before they are displayed.
5166
5167 @item -p <number or name>
5168 @itemx --string-dump=<number or name>
5169 Displays the contents of the indicated section as printable strings.
5170 A number identifies a particular section by index in the section table;
5171 any other string identifies all sections with that name in the object file.
5172
5173 @item -z
5174 @itemx --decompress
5175 Requests that the section(s) being dumped by @option{x}, @option{R} or
5176 @option{p} options are decompressed before being displayed. If the
5177 section(s) are not compressed then they are displayed as is.
5178
5179 @item -c
5180 @itemx --archive-index
5181 @cindex Archive file symbol index information
5182 Displays the file symbol index information contained in the header part
5183 of binary archives. Performs the same function as the @option{t}
5184 command to @command{ar}, but without using the BFD library. @xref{ar}.
5185
5186 @item -w[lLiaprmfFsOoRtUuTgAckK]
5187 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
5188 @include debug.options.texi
5189
5190 @item -P
5191 @itemx --process-links
5192 Display the contents of non-debug sections found in separate debuginfo
5193 files that are linked to the main file. This option automatically
5194 implies the @option{-wK} option, and only sections requested by other
5195 command line options will be displayed.
5196
5197 @include ctf.options.texi
5198 @item --ctf-symbols=@var{section}
5199 @item --ctf-strings=@var{section}
5200 Specify the name of another section from which the CTF file can inherit
5201 strings and symbols. By default, the @code{.symtab} and its linked
5202 string table are used.
5203
5204 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
5205 other must be specified as well.
5206
5207 @item -I
5208 @itemx --histogram
5209 Display a histogram of bucket list lengths when displaying the contents
5210 of the symbol tables.
5211
5212 @item -v
5213 @itemx --version
5214 Display the version number of readelf.
5215
5216 @item -W
5217 @itemx --wide
5218 Don't break output lines to fit into 80 columns. By default
5219 @command{readelf} breaks section header and segment listing lines for
5220 64-bit ELF files, so that they fit into 80 columns. This option causes
5221 @command{readelf} to print each section header resp. each segment one a
5222 single line, which is far more readable on terminals wider than 80 columns.
5223
5224 @item -T
5225 @itemx --silent-truncation
5226 Normally when readelf is displaying a symbol name, and it has to
5227 truncate the name to fit into an 80 column display, it will add a
5228 suffix of @code{[...]} to the name. This command line option
5229 disables this behaviour, allowing 5 more characters of the name to be
5230 displayed and restoring the old behaviour of readelf (prior to release
5231 2.35).
5232
5233 @item -H
5234 @itemx --help
5235 Display the command-line options understood by @command{readelf}.
5236
5237 @end table
5238
5239 @c man end
5240
5241 @ignore
5242 @c man begin SEEALSO readelf
5243 objdump(1), and the Info entries for @file{binutils}.
5244 @c man end
5245 @end ignore
5246
5247 @node elfedit
5248 @chapter elfedit
5249
5250 @cindex Update ELF header
5251 @kindex elfedit
5252
5253 @c man title elfedit update ELF header and program property of ELF files
5254
5255 @smallexample
5256 @c man begin SYNOPSIS elfedit
5257 elfedit [@option{--input-mach=}@var{machine}]
5258 [@option{--input-type=}@var{type}]
5259 [@option{--input-osabi=}@var{osabi}]
5260 [@option{--input-abiversion=}@var{version}]
5261 @option{--output-mach=}@var{machine}
5262 @option{--output-type=}@var{type}
5263 @option{--output-osabi=}@var{osabi}
5264 @option{--output-abiversion=}@var{version}
5265 @option{--enable-x86-feature=}@var{feature}
5266 @option{--disable-x86-feature=}@var{feature}
5267 [@option{-v}|@option{--version}]
5268 [@option{-h}|@option{--help}]
5269 @var{elffile}@dots{}
5270 @c man end
5271 @end smallexample
5272
5273 @c man begin DESCRIPTION elfedit
5274
5275 @command{elfedit} updates the ELF header and program property of ELF
5276 files which have the matching ELF machine and file types. The options
5277 control how and which fields in the ELF header and program property
5278 should be updated.
5279
5280 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
5281 64-bit ELF files are supported, as are archives containing ELF files.
5282 @c man end
5283
5284 @c man begin OPTIONS elfedit
5285
5286 The long and short forms of options, shown here as alternatives, are
5287 equivalent. At least one of the @option{--output-mach},
5288 @option{--output-type}, @option{--output-osabi},
5289 @option{--output-abiversion},
5290 @option{--enable-x86-feature} and @option{--disable-x86-feature}
5291 options must be given.
5292
5293 @table @env
5294
5295 @item --input-mach=@var{machine}
5296 Set the matching input ELF machine type to @var{machine}. If
5297 @option{--input-mach} isn't specified, it will match any ELF
5298 machine types.
5299
5300 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5301 @var{K1OM} and @var{x86-64}.
5302
5303 @item --output-mach=@var{machine}
5304 Change the ELF machine type in the ELF header to @var{machine}. The
5305 supported ELF machine types are the same as @option{--input-mach}.
5306
5307 @item --input-type=@var{type}
5308 Set the matching input ELF file type to @var{type}. If
5309 @option{--input-type} isn't specified, it will match any ELF file types.
5310
5311 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5312
5313 @item --output-type=@var{type}
5314 Change the ELF file type in the ELF header to @var{type}. The
5315 supported ELF types are the same as @option{--input-type}.
5316
5317 @item --input-osabi=@var{osabi}
5318 Set the matching input ELF file OSABI to @var{osabi}. If
5319 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5320
5321 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5322 @var{GNU}, @var{Linux} (alias for @var{GNU}),
5323 @var{Solaris}, @var{AIX}, @var{Irix},
5324 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5325 @var{NSK}, @var{AROS} and @var{FenixOS}.
5326
5327 @item --output-osabi=@var{osabi}
5328 Change the ELF OSABI in the ELF header to @var{osabi}. The
5329 supported ELF OSABI are the same as @option{--input-osabi}.
5330
5331 @item --input-abiversion=@var{version}
5332 Set the matching input ELF file ABIVERSION to @var{version}.
5333 @var{version} must be between 0 and 255. If @option{--input-abiversion}
5334 isn't specified, it will match any ELF ABIVERSIONs.
5335
5336 @item --output-abiversion=@var{version}
5337 Change the ELF ABIVERSION in the ELF header to @var{version}.
5338 @var{version} must be between 0 and 255.
5339
5340 @item --enable-x86-feature=@var{feature}
5341 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5342 ELF files with machine types of @var{i386} or @var{x86-64}. The
5343 supported features are, @var{ibt}, @var{shstk}, @var{lam_u48} and
5344 @var{lam_u57}.
5345
5346 @item --disable-x86-feature=@var{feature}
5347 Clear the @var{feature} bit in program property in @var{exec} or
5348 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5349 The supported features are the same as @option{--enable-x86-feature}.
5350
5351 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5352 are available only on hosts with @samp{mmap} support.
5353
5354 @item -v
5355 @itemx --version
5356 Display the version number of @command{elfedit}.
5357
5358 @item -h
5359 @itemx --help
5360 Display the command-line options understood by @command{elfedit}.
5361
5362 @end table
5363
5364 @c man end
5365
5366 @ignore
5367 @c man begin SEEALSO elfedit
5368 readelf(1), and the Info entries for @file{binutils}.
5369 @c man end
5370 @end ignore
5371
5372 @node Common Options
5373 @chapter Common Options
5374
5375 The following command-line options are supported by all of the
5376 programs described in this manual.
5377
5378 @c man begin OPTIONS
5379 @table @env
5380 @include at-file.texi
5381 @c man end
5382
5383 @item --help
5384 Display the command-line options supported by the program.
5385
5386 @item --version
5387 Display the version number of the program.
5388
5389 @c man begin OPTIONS
5390 @end table
5391 @c man end
5392
5393 @node Selecting the Target System
5394 @chapter Selecting the Target System
5395
5396 You can specify two aspects of the target system to the @sc{gnu}
5397 binary file utilities, each in several ways:
5398
5399 @itemize @bullet
5400 @item
5401 the target
5402
5403 @item
5404 the architecture
5405 @end itemize
5406
5407 In the following summaries, the lists of ways to specify values are in
5408 order of decreasing precedence. The ways listed first override those
5409 listed later.
5410
5411 The commands to list valid values only list the values for which the
5412 programs you are running were configured. If they were configured with
5413 @option{--enable-targets=all}, the commands list most of the available
5414 values, but a few are left out; not all targets can be configured in at
5415 once because some of them can only be configured @dfn{native} (on hosts
5416 with the same type as the target system).
5417
5418 @menu
5419 * Target Selection::
5420 * Architecture Selection::
5421 @end menu
5422
5423 @node Target Selection
5424 @section Target Selection
5425
5426 A @dfn{target} is an object file format. A given target may be
5427 supported for multiple architectures (@pxref{Architecture Selection}).
5428 A target selection may also have variations for different operating
5429 systems or architectures.
5430
5431 The command to list valid target values is @samp{objdump -i}
5432 (the first column of output contains the relevant information).
5433
5434 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5435 @samp{a.out-sunos-big}.
5436
5437 You can also specify a target using a configuration triplet. This is
5438 the same sort of name that is passed to @file{configure} to specify a
5439 target. When you use a configuration triplet as an argument, it must be
5440 fully canonicalized. You can see the canonical version of a triplet by
5441 running the shell script @file{config.sub} which is included with the
5442 sources.
5443
5444 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5445 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5446
5447 @subheading @command{objdump} Target
5448
5449 Ways to specify:
5450
5451 @enumerate
5452 @item
5453 command-line option: @option{-b} or @option{--target}
5454
5455 @item
5456 environment variable @code{GNUTARGET}
5457
5458 @item
5459 deduced from the input file
5460 @end enumerate
5461
5462 @subheading @command{objcopy} and @command{strip} Input Target
5463
5464 Ways to specify:
5465
5466 @enumerate
5467 @item
5468 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5469
5470 @item
5471 environment variable @code{GNUTARGET}
5472
5473 @item
5474 deduced from the input file
5475 @end enumerate
5476
5477 @subheading @command{objcopy} and @command{strip} Output Target
5478
5479 Ways to specify:
5480
5481 @enumerate
5482 @item
5483 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5484
5485 @item
5486 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5487
5488 @item
5489 environment variable @code{GNUTARGET}
5490
5491 @item
5492 deduced from the input file
5493 @end enumerate
5494
5495 @subheading @command{nm}, @command{size}, and @command{strings} Target
5496
5497 Ways to specify:
5498
5499 @enumerate
5500 @item
5501 command-line option: @option{--target}
5502
5503 @item
5504 environment variable @code{GNUTARGET}
5505
5506 @item
5507 deduced from the input file
5508 @end enumerate
5509
5510 @node Architecture Selection
5511 @section Architecture Selection
5512
5513 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5514 to run. Its name may contain a colon, separating the name of the
5515 processor family from the name of the particular @sc{cpu}.
5516
5517 The command to list valid architecture values is @samp{objdump -i} (the
5518 second column contains the relevant information).
5519
5520 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5521
5522 @subheading @command{objdump} Architecture
5523
5524 Ways to specify:
5525
5526 @enumerate
5527 @item
5528 command-line option: @option{-m} or @option{--architecture}
5529
5530 @item
5531 deduced from the input file
5532 @end enumerate
5533
5534 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5535
5536 Ways to specify:
5537
5538 @enumerate
5539 @item
5540 deduced from the input file
5541 @end enumerate
5542
5543 @node debuginfod
5544 @chapter debuginfod
5545 @cindex separate debug files
5546
5547 debuginfod is a web service that indexes ELF/DWARF debugging resources
5548 by build-id and serves them over HTTP. For more information see:
5549 @emph{https://sourceware.org/elfutils/Debuginfod.html}
5550
5551 Binutils can be built with the debuginfod client library
5552 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5553 This option is enabled by default if @code{libdebuginfod} is installed
5554 and found at configure time. This allows @command{objdump} and
5555 @command{readelf} to automatically query debuginfod servers for
5556 separate debug files when the files are otherwise not found.
5557
5558 debuginfod is packaged with elfutils, starting with version 0.178.
5559 You can get the latest version from `https://sourceware.org/elfutils/'.
5560
5561 The DWARF info dumping tools (@command{readelf} and @command{objdump})
5562 have options to control when they should access the debuginfod
5563 servers. By default this access is enabled.
5564
5565 @node Reporting Bugs
5566 @chapter Reporting Bugs
5567 @cindex bugs
5568 @cindex reporting bugs
5569
5570 Your bug reports play an essential role in making the binary utilities
5571 reliable.
5572
5573 Reporting a bug may help you by bringing a solution to your problem, or
5574 it may not. But in any case the principal function of a bug report is
5575 to help the entire community by making the next version of the binary
5576 utilities work better. Bug reports are your contribution to their
5577 maintenance.
5578
5579 In order for a bug report to serve its purpose, you must include the
5580 information that enables us to fix the bug.
5581
5582 @menu
5583 * Bug Criteria:: Have you found a bug?
5584 * Bug Reporting:: How to report bugs
5585 @end menu
5586
5587 @node Bug Criteria
5588 @section Have You Found a Bug?
5589 @cindex bug criteria
5590
5591 If you are not sure whether you have found a bug, here are some guidelines:
5592
5593 @itemize @bullet
5594 @cindex fatal signal
5595 @cindex crash
5596 @item
5597 If a binary utility gets a fatal signal, for any input whatever, that is
5598 a bug. Reliable utilities never crash.
5599
5600 @cindex error on valid input
5601 @item
5602 If a binary utility produces an error message for valid input, that is a
5603 bug.
5604
5605 @item
5606 If you are an experienced user of binary utilities, your suggestions for
5607 improvement are welcome in any case.
5608 @end itemize
5609
5610 @node Bug Reporting
5611 @section How to Report Bugs
5612 @cindex bug reports
5613 @cindex bugs, reporting
5614
5615 A number of companies and individuals offer support for @sc{gnu}
5616 products. If you obtained the binary utilities from a support
5617 organization, we recommend you contact that organization first.
5618
5619 You can find contact information for many support companies and
5620 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5621 distribution.
5622
5623 @ifset BUGURL
5624 In any event, we also recommend that you send bug reports for the binary
5625 utilities to @value{BUGURL}.
5626 @end ifset
5627
5628 The fundamental principle of reporting bugs usefully is this:
5629 @strong{report all the facts}. If you are not sure whether to state a
5630 fact or leave it out, state it!
5631
5632 Often people omit facts because they think they know what causes the
5633 problem and assume that some details do not matter. Thus, you might
5634 assume that the name of a file you use in an example does not matter.
5635 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5636 a stray memory reference which happens to fetch from the location where
5637 that pathname is stored in memory; perhaps, if the pathname were
5638 different, the contents of that location would fool the utility into
5639 doing the right thing despite the bug. Play it safe and give a
5640 specific, complete example. That is the easiest thing for you to do,
5641 and the most helpful.
5642
5643 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5644 it is new to us. Therefore, always write your bug reports on the assumption
5645 that the bug has not been reported previously.
5646
5647 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5648 bell?'' This cannot help us fix a bug, so it is basically useless. We
5649 respond by asking for enough details to enable us to investigate.
5650 You might as well expedite matters by sending them to begin with.
5651
5652 To enable us to fix the bug, you should include all these things:
5653
5654 @itemize @bullet
5655 @item
5656 The version of the utility. Each utility announces it if you start it
5657 with the @option{--version} argument.
5658
5659 Without this, we will not know whether there is any point in looking for
5660 the bug in the current version of the binary utilities.
5661
5662 @item
5663 Any patches you may have applied to the source, including any patches
5664 made to the @code{BFD} library.
5665
5666 @item
5667 The type of machine you are using, and the operating system name and
5668 version number.
5669
5670 @item
5671 What compiler (and its version) was used to compile the utilities---e.g.
5672 ``@code{gcc-2.7}''.
5673
5674 @item
5675 The command arguments you gave the utility to observe the bug. To
5676 guarantee you will not omit something important, list them all. A copy
5677 of the Makefile (or the output from make) is sufficient.
5678
5679 If we were to try to guess the arguments, we would probably guess wrong
5680 and then we might not encounter the bug.
5681
5682 @item
5683 A complete input file, or set of input files, that will reproduce the
5684 bug. If the utility is reading an object file or files, then it is
5685 generally most helpful to send the actual object files.
5686
5687 If the source files were produced exclusively using @sc{gnu} programs
5688 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5689 may be OK to send the source files rather than the object files. In
5690 this case, be sure to say exactly what version of @command{gcc}, or
5691 whatever, was used to produce the object files. Also say how
5692 @command{gcc}, or whatever, was configured.
5693
5694 @item
5695 A description of what behavior you observe that you believe is
5696 incorrect. For example, ``It gets a fatal signal.''
5697
5698 Of course, if the bug is that the utility gets a fatal signal, then we
5699 will certainly notice it. But if the bug is incorrect output, we might
5700 not notice unless it is glaringly wrong. You might as well not give us
5701 a chance to make a mistake.
5702
5703 Even if the problem you experience is a fatal signal, you should still
5704 say so explicitly. Suppose something strange is going on, such as your
5705 copy of the utility is out of sync, or you have encountered a bug in
5706 the C library on your system. (This has happened!) Your copy might
5707 crash and ours would not. If you told us to expect a crash, then when
5708 ours fails to crash, we would know that the bug was not happening for
5709 us. If you had not told us to expect a crash, then we would not be able
5710 to draw any conclusion from our observations.
5711
5712 @item
5713 If you wish to suggest changes to the source, send us context diffs, as
5714 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5715 option. Always send diffs from the old file to the new file. If you
5716 wish to discuss something in the @command{ld} source, refer to it by
5717 context, not by line number.
5718
5719 The line numbers in our development sources will not match those in your
5720 sources. Your line numbers would convey no useful information to us.
5721 @end itemize
5722
5723 Here are some things that are not necessary:
5724
5725 @itemize @bullet
5726 @item
5727 A description of the envelope of the bug.
5728
5729 Often people who encounter a bug spend a lot of time investigating
5730 which changes to the input file will make the bug go away and which
5731 changes will not affect it.
5732
5733 This is often time consuming and not very useful, because the way we
5734 will find the bug is by running a single example under the debugger
5735 with breakpoints, not by pure deduction from a series of examples.
5736 We recommend that you save your time for something else.
5737
5738 Of course, if you can find a simpler example to report @emph{instead}
5739 of the original one, that is a convenience for us. Errors in the
5740 output will be easier to spot, running under the debugger will take
5741 less time, and so on.
5742
5743 However, simplification is not vital; if you do not want to do this,
5744 report the bug anyway and send us the entire test case you used.
5745
5746 @item
5747 A patch for the bug.
5748
5749 A patch for the bug does help us if it is a good one. But do not omit
5750 the necessary information, such as the test case, on the assumption that
5751 a patch is all we need. We might see problems with your patch and decide
5752 to fix the problem another way, or we might not understand it at all.
5753
5754 Sometimes with programs as complicated as the binary utilities it is
5755 very hard to construct an example that will make the program follow a
5756 certain path through the code. If you do not send us the example, we
5757 will not be able to construct one, so we will not be able to verify that
5758 the bug is fixed.
5759
5760 And if we cannot understand what bug you are trying to fix, or why your
5761 patch should be an improvement, we will not install it. A test case will
5762 help us to understand.
5763
5764 @item
5765 A guess about what the bug is or what it depends on.
5766
5767 Such guesses are usually wrong. Even we cannot guess right about such
5768 things without first using the debugger to find the facts.
5769 @end itemize
5770
5771 @node GNU Free Documentation License
5772 @appendix GNU Free Documentation License
5773
5774 @include fdl.texi
5775
5776 @node Binutils Index
5777 @unnumbered Binutils Index
5778
5779 @printindex cp
5780
5781 @bye