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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
13Copyright @copyright{} 1991-2025 Free Software Foundation, Inc.
14
15Permission is granted to copy, distribute and/or modify this document
16under the terms of the GNU Free Documentation License, Version 1.3
17or any later version published by the Free Software Foundation;
18with no Invariant Sections, with no Front-Cover Texts, and with no
19Back-Cover Texts. A copy of the license is included in the
20section 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
65Texinfo \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
77This brief manual contains documentation for the @sc{gnu} binary
78utilities
79@ifset VERSION_PACKAGE
80@value{VERSION_PACKAGE}
81@end ifset
82version @value{VERSION}:
83
84@iftex
85@table @code
86@item ar
87Create, modify, and extract from archives
88
89@item nm
90List symbols from object files
91
92@item objcopy
93Copy and translate object files
94
95@item objdump
96Display information from object files
97
98@item ranlib
99Generate index to archive contents
100
101@item readelf
102Display the contents of ELF format files.
103
104@item size
105List file section sizes and total size
106
107@item strings
108List printable strings from files
109
110@item strip
111Discard symbols
112
113@item elfedit
114Update the ELF header and program property of ELF files.
115
116@item c++filt
117Demangle encoded C++ symbols (on MS-DOS, this program is named
118@code{cxxfilt})
119
120@item addr2line
121Convert addresses or symbol+offset into file names and line numbers
122
123@item windres
124Manipulate Windows resources
125
126@item windmc
127Generator for Windows message resources
128
129@item dlltool
130Create the files needed to build and use Dynamic Link Libraries
131@end table
132@end iftex
133
134This document is distributed under the terms of the GNU Free
135Documentation License version 1.3. A copy of the license is included
136in 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
173ar [-]@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{}]
174ar -M [ <mri-script ]
175@end smallexample
176
177@c man begin DESCRIPTION ar
178
179The @sc{gnu} @command{ar} program creates, modifies, and extracts from
180archives. An @dfn{archive} is a single file holding a collection of
181other files in a structure that makes it possible to retrieve
182the original individual files (called @dfn{members} of the archive).
183
184The original files' contents, mode (permissions), timestamp, owner, and
185group are preserved in the archive, and can be restored on
186extraction.
187
188@cindex name length
189@sc{gnu} @command{ar} can maintain archives whose members have names of any
190length; however, depending on how @command{ar} is configured on your
191system, a limit on member-name length may be imposed for compatibility
192with archive formats maintained with other tools. If it exists, the
193limit is often 15 characters (typical of formats related to a.out) or 16
194characters (typical of formats related to coff).
195
196@cindex libraries
197@command{ar} is considered a binary utility because archives of this sort
198are most often used as @dfn{libraries} holding commonly needed
199subroutines. 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
205object modules in the archive when you specify the modifier @samp{s}.
206Once created, this index is updated in the archive whenever @command{ar}
207makes a change to its contents (save for the @samp{q} update operation).
208An archive with such an index speeds up linking to the library, and
209allows routines in the library to call each other without regard to
210their placement in the archive.
211
212You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
213table. 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,
218which contains a symbol index and references to the original copies
219of the member files of the archive. This is useful for building
220libraries for use within a local build tree, where the relocatable
221objects are expected to remain available, and copying the contents of
222each object would only waste time and space.
223
224An archive can either be @emph{thin} or it can be normal. It cannot
225be both at the same time. Once an archive is created its format
226cannot be changed without first deleting it and then creating a new
227archive in its place.
228
229Thin archives are also @emph{flattened}, so that adding one thin
230archive to another thin archive does not nest it, as would happen with
231a normal archive. Instead the elements of the first archive are added
232individually to the second archive.
233
234The paths to the elements of the archive are stored relative to the
235archive 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
240facilities. You can control its activity using command-line options,
241like the different varieties of @command{ar} on Unix systems; or, if you
242specify the single command-line option @option{-M}, you can control it
243with a script supplied via standard input, like the MRI ``librarian''
244program.
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
259ar [@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}
264When you use @command{ar} in the Unix style, @command{ar} insists on at least two
265arguments 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
269Most operations can also accept further @var{member} arguments,
270specifying 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
275flags @var{mod} in any order, within the first command-line argument.
276
277If you wish, you may begin the first command-line argument with a
278dash.
279
280@cindex operations on archive
281The @var{p} keyletter specifies what operation to execute; it may be
282any 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
288be deleted as @var{member}@dots{}; the archive is untouched if you
289specify no files to delete.
290
291If you specify the @samp{v} modifier, @command{ar} lists each module
292as it is deleted.
293
294@item m
295@cindex moving in archive
296Use this operation to @emph{move} members in an archive.
297
298The ordering of members in an archive can make a difference in how
299programs are linked using the library, if a symbol is defined in more
300than one member.
301
302If 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;
304you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
305specified place instead.
306
307@item p
308@cindex printing from archive
309@emph{Print} the specified members of the archive, to the standard
310output file. If the @samp{v} modifier is specified, show the member
311name before copying its contents to standard output.
312
313If you specify no @var{member} arguments, all the files in the archive are
314printed.
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
321The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
322operation; new members are always placed at the end of the archive.
323
324The modifier @samp{v} makes @command{ar} list each file as it is appended.
325
326Since the point of this operation is speed, implementations of
327@command{ar} have the option of not updating the archive's symbol
328table if one exists. Too many different systems however assume that
329symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
330rebuild the table even with a quick append.
331
332Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
333synonym for @samp{r} - replacing already existing files in the
334archive and appending new ones at the end.
335
336@item r
337@cindex replacement in archive
338Insert the files @var{member}@dots{} into @var{archive} (with
339@emph{replacement}). This operation differs from @samp{q} in that any
340previously existing members are deleted if their names match those being
341added.
342
343If one of the files named in @var{member}@dots{} does not exist, @command{ar}
344displays an error message, and leaves undisturbed any existing members
345of the archive matching that name.
346
347By default, new members are added at the end of the file; but you may
348use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
349placement relative to some existing member.
350
351The modifier @samp{v} used with this operation elicits a line of
352output 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
354deleted) or replaced.
355
356@item s
357@cindex ranlib
358Add an index to the archive, or update it if it already exists. Note
359this command is an exception to the rule that there can only be one
360command letter, as it is possible to use it as either a command or a
361modifier. In either case it does the same thing.
362
363@item t
364@cindex contents of archive
365Display a @emph{table} listing the contents of @var{archive}, or those
366of the files listed in @var{member}@dots{} that are present in the
367archive. 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
369displayed. Finally, in order to see the modes (permissions), timestamp,
370owner, group, and size the @samp{v} modifier should be included.
371
372If you do not specify a @var{member}, all files in the archive
373are listed.
374
375@cindex repeated names in archive
376@cindex name duplication in archive
377If there is more than one file with the same name (say, @samp{fie}) in
378an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
379first instance; to see them all, you must ask for a complete
380listing---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
387use the @samp{v} modifier with this operation, to request that
388@command{ar} list each name as it extracts it.
389
390If you do not specify a @var{member}, all files in the archive
391are extracted.
392
393Files cannot be extracted from a thin archive, and there are
394restrictions on extracting from archives created with @option{P}: The
395paths must not be absolute, may not contain @code{..}, and any
396subdirectories in the paths must exist. If it is desired to avoid
397these restrictions then used the @option{--output} option to specify
398an output directory.
399@end table
400
401A number of modifiers (@var{mod}) may immediately follow the @var{p}
402keyletter, to specify variations on an operation's behavior:
403
404@table @samp
405@item a
406@cindex relative placement in archive
407Add new files @emph{after} an existing member of the
408archive. If you use the modifier @samp{a}, the name of an existing archive
409member must be present as the @var{relpos} argument, before the
410@var{archive} specification.
411
412@item b
413Add new files @emph{before} an existing member of the
414archive. If you use the modifier @samp{b}, the name of an existing archive
415member 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
421created if it did not exist, when you request an update. But a warning is
422issued unless you specify in advance that you expect to create it, by
423using this modifier.
424
425@item D
426@cindex deterministic archives
427@kindex --enable-deterministic-archives
428Operate in @emph{deterministic} mode. When adding files and the archive
429index use zero for UIDs, GIDs, timestamps, and use consistent file modes
430for all files. When this option is used, if @command{ar} is used with
431identical options and identical input files, multiple runs will create
432identical output files regardless of the input files' owners, groups,
433file modes, or modification times.
434
435If @file{binutils} was configured with
436@option{--enable-deterministic-archives}, then this mode is on by default.
437It can be disabled with the @samp{U} modifier, below.
438
439@item f
440Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
441names of any length. This will cause it to create archives which are
442not compatible with the native @command{ar} program on some systems. If
443this is a concern, the @samp{f} modifier may be used to truncate file
444names when putting them in the archive.
445
446@item i
447Insert new files @emph{before} an existing member of the
448archive. If you use the modifier @samp{i}, the name of an existing archive
449member 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
456Specify dependencies of this library. The dependencies must immediately
457follow this option character, must use the same syntax as the linker
458command line, and must be specified within a single argument. I.e., if
459multiple items are needed, they must be quoted to form a single command
460line argument. For example @samp{l "-L/usr/local/lib -lmydep1 -lmydep2"}
461
462@item N
463Uses the @var{count} parameter. This is used if there are multiple
464entries 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
469Preserve the @emph{original} dates of members when extracting them. If
470you do not specify this modifier, files extracted from the archive
471are stamped with the time of extraction.
472
473@item O
474@cindex offsets of files
475Display member offsets inside the archive. Use together with the @samp{t}
476option.
477
478@item P
479Use the full path name when matching or storing names in the archive.
480Archives created with full path names are not POSIX compliant, and
481thus may not work with tools other than up to date @sc{gnu} tools.
482Modifying such archives with @sc{gnu} @command{ar} without using
483@option{P} will remove the full path names unless the archive is a
484thin archive. Note that @option{P} may be useful when adding files to
485a thin archive since @option{r} without @option{P} ignores the path
486when choosing which element to replace. Thus
487@smallexample
488ar rcST archive.a subdir/file1 subdir/file2 file1
489@end smallexample
490will result in the first @code{subdir/file1} being replaced with
491@code{file1} from the current directory. Adding @option{P} will
492prevent this replacement.
493
494@item s
495@cindex writing archive index
496Write an object-file index into the archive, or update an existing one,
497even if no other change is made to the archive. You may use this modifier
498flag either with any operation, or alone. Running @samp{ar s} on an
499archive is equivalent to running @samp{ranlib} on it.
500
501@item S
502@cindex not writing archive index
503Do not generate an archive symbol table. This can speed up building a
504large library in several steps. The resulting archive can not be used
505with 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
510Deprecated alias for @option{--thin}. @option{T} is not recommended because in
511many ar implementations @option{T} has a different meaning, as specified by
512X/Open System Interface.
513
514@item u
515@cindex updating an archive
516Normally, @samp{ar r}@dots{} inserts all files
517listed into the archive. If you would like to insert @emph{only} those
518of the files you list that are newer than existing members of the same
519names, use this modifier. The @samp{u} modifier is allowed only for the
520operation @samp{r} (replace). In particular, the combination @samp{qu} is
521not allowed, since checking the timestamps would lose any speed
522advantage from the operation @samp{q}.
523
524Note - if an archive has been created in a deterministic manner, eg
525via the use of the @option{D} modifier, then replacement will always
526happen and the @option{u} modifier will be ineffective.
527
528@item U
529@cindex deterministic archives
530@kindex --enable-deterministic-archives
531Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
532of the @samp{D} modifier, above: added files and the archive index will
533get their actual UID, GID, timestamp, and file mode values.
534
535This is the default unless @file{binutils} was configured with
536@option{--enable-deterministic-archives}.
537
538@item v
539This modifier requests the @emph{verbose} version of an operation. Many
540operations display additional information, such as filenames processed,
541when the modifier @samp{v} is appended.
542
543@item V
544This modifier shows the version number of @command{ar}.
545@end table
546
547The @command{ar} program also supports some command-line options which
548are neither modifiers nor actions, but which do change its behaviour
549in specific ways:
550
551@table @samp
552@item --help
553Displays the list of command-line options supported by @command{ar}
554and then exits.
555
556@item --version
557Displays the version information of @command{ar} and then exits.
558
559@item -X32_64
560@command{ar} ignores an initial option spelled @samp{-X32_64}, for
561compatibility with AIX. The behaviour produced by this option is the
562default for @sc{gnu} @command{ar}. @command{ar} does not support any
563of the other @samp{-X} options; in particular, it does not support
564@option{-X32} which is the default for AIX @command{ar}.
565
566@item --plugin @var{name}
567@cindex plugins
568The optional command-line switch @option{--plugin @var{name}} causes
569@command{ar} to load the plugin called @var{name} which adds support
570for more file formats, including object files with link-time
571optimization information.
572
573This option is only available if the toolchain has been built with
574plugin support enabled.
575
576If @option{--plugin} is not provided, but plugin support has been
577enabled then @command{ar} iterates over the files in
578@file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
579plugin that claims the object in question is used.
580
581Please note that this plugin search directory is @emph{not} the one
582used by @command{ld}'s @option{-plugin} option. In order to make
583@command{ar} use the linker plugin it must be copied into the
584@file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
585the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
586based compilations it is called @file{LLVMgold.so}. The GCC plugin
587is always backwards compatible with earlier versions, so it is
588sufficient to just copy the newest one.
589
590@item --target @var{target}
591The optional command-line switch @option{--target @var{bfdname}}
592specifies that the archive members are in an object code format
593different from your system's default format. See
594@xref{Target Selection}, for more information.
595
596@item --output @var{dirname}
597The @option{--output} option can be used to specify a path to a
598directory into which archive members should be extracted. If this
599option is not specified then the current directory will be used.
600
601Note - although the presence of this option does imply a @option{x}
602extraction operation that option must still be included on the command
603line.
604
605@item --record-libdeps @var{libdeps}
606The @option{--record-libdeps} option is identical to the @option{l} modifier,
607just handled in long form.
608
609@item --thin
610@cindex creating thin archive
611Make the specified @var{archive} a @emph{thin} archive. If it already
612exists and is a regular archive, the existing members must be present
613in the same directory as @var{archive}.
614
615@end table
616@c man end
617
618@ignore
619@c man begin SEEALSO ar
620nm(1), ranlib(1), and the Info entries for @file{binutils}.
621@c man end
622@end ignore
623
624@node ar scripts
625@section Controlling @command{ar} with a Script
626
627@smallexample
628ar -M [ <@var{script} ]
629@end smallexample
630
631@cindex MRI compatibility, @command{ar}
632@cindex scripts, @command{ar}
633If you use the single command-line option @samp{-M} with @command{ar}, you
634can control its operation with a rudimentary command language. This
635form of @command{ar} operates interactively if standard input is coming
636directly from a terminal. During interactive use, @command{ar} prompts for
637input (the prompt is @samp{AR >}), and continues executing even after
638errors. If you redirect standard input to a script file, no prompts are
639issued, and @command{ar} abandons execution (with a nonzero exit code)
640on any error.
641
642The @command{ar} command language is @emph{not} designed to be equivalent
643to the command-line options; in fact, it provides somewhat less control
644over archives. The only purpose of the command language is to ease the
645transition to @sc{gnu} @command{ar} for developers who already have scripts
646written for the MRI ``librarian'' program.
647
648The syntax for the @command{ar} command language is straightforward:
649@itemize @bullet
650@item
651commands are recognized in upper or lower case; for example, @code{LIST}
652is the same as @code{list}. In the following descriptions, commands are
653shown in upper case for clarity.
654
655@item
656a single command may appear on each line; it is the first word on the
657line.
658
659@item
660empty lines are allowed, and have no effect.
661
662@item
663comments are allowed; text after either of the characters @samp{*}
664or @samp{;} is ignored.
665
666@item
667Whenever you use a list of names as part of the argument to an @command{ar}
668command, you can separate the individual names with either commas or
669blanks. Commas are shown in the explanations below, for clarity.
670
671@item
672@samp{+} is used as a line continuation character; if @samp{+} appears
673at the end of a line, the text on the following line is considered part
674of the current command.
675@end itemize
676
677Here are the commands you can use in @command{ar} scripts, or when using
678@command{ar} interactively. Three of them have special significance:
679
680@code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
681a temporary file required for most of the other commands.
682
683@code{SAVE} commits the changes so far specified by the script. Prior
684to @code{SAVE}, commands affect only the temporary copy of the current
685archive.
686
687@table @code
688@item ADDLIB @var{archive}
689@itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
690Add all the contents of @var{archive} (or, if specified, each named
691@var{module} from @var{archive}) to the current archive.
692
693Requires prior use of @code{OPEN} or @code{CREATE}.
694
695@item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
696@c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
697@c else like "ar q..."
698Add each named @var{member} as a module in the current archive.
699
700Requires prior use of @code{OPEN} or @code{CREATE}.
701
702@item CLEAR
703Discard the contents of the current archive, canceling the effect of
704any operations since the last @code{SAVE}. May be executed (with no
705effect) even if no current archive is specified.
706
707@item CREATE @var{archive}
708Creates an archive, and makes it the current archive (required for many
709other commands). The new archive is created with a temporary name; it
710is not actually saved as @var{archive} until you use @code{SAVE}.
711You can overwrite existing archives; similarly, the contents of any
712existing file named @var{archive} will not be destroyed until @code{SAVE}.
713
714@item DELETE @var{module}, @var{module}, @dots{} @var{module}
715Delete each listed @var{module} from the current archive; equivalent to
716@samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
717
718Requires prior use of @code{OPEN} or @code{CREATE}.
719
720@item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
721@itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
722List each named @var{module} present in @var{archive}. The separate
723command @code{VERBOSE} specifies the form of the output: when verbose
724output is off, output is like that of @samp{ar -t @var{archive}
725@var{module}@dots{}}. When verbose output is on, the listing is like
726@samp{ar -tv @var{archive} @var{module}@dots{}}.
727
728Output normally goes to the standard output stream; however, if you
729specify @var{outputfile} as a final argument, @command{ar} directs the
730output to that file.
731
732@item END
733Exit from @command{ar}, with a @code{0} exit code to indicate successful
734completion. This command does not save the output file; if you have
735changed the current archive since the last @code{SAVE} command, those
736changes are lost.
737
738@item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
739Extract each named @var{module} from the current archive, writing them
740into the current directory as separate files. Equivalent to @samp{ar -x
741@var{archive} @var{module}@dots{}}.
742
743Requires prior use of @code{OPEN} or @code{CREATE}.
744
745@ignore
746@c FIXME Tokens but no commands???
747@item FULLDIR
748
749@item HELP
750@end ignore
751
752@item LIST
753Display full contents of the current archive, in ``verbose'' style
754regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
755tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
756enhancement, rather than present for MRI compatibility.)
757
758Requires prior use of @code{OPEN} or @code{CREATE}.
759
760@item OPEN @var{archive}
761Opens an existing archive for use as the current archive (required for
762many other commands). Any changes as the result of subsequent commands
763will not actually affect @var{archive} until you next use @code{SAVE}.
764
765@item REPLACE @var{module}, @var{module}, @dots{} @var{module}
766In the current archive, replace each existing @var{module} (named in
767the @code{REPLACE} arguments) from files in the current working directory.
768To execute this command without errors, both the file, and the module in
769the current archive, must exist.
770
771Requires prior use of @code{OPEN} or @code{CREATE}.
772
773@item VERBOSE
774Toggle an internal flag governing the output from @code{DIRECTORY}.
775When the flag is on, @code{DIRECTORY} output matches output from
776@samp{ar -tv }@dots{}.
777
778@item SAVE
779Commit your changes to the current archive, and actually save it as a
780file with the name specified in the last @code{CREATE} or @code{OPEN}
781command.
782
783Requires prior use of @code{OPEN} or @code{CREATE}.
784
785@end table
786
787@iftex
788@node ld
789@chapter ld
790@cindex linker
791@kindex ld
792The @sc{gnu} linker @command{ld} is now described in a separate manual.
793@xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
794@end iftex
795
796@node nm
797@chapter nm
798@cindex symbols
799@kindex nm
800
801@c man title nm list symbols from object files
802
803@smallexample
804@c man begin SYNOPSIS nm
805nm [@option{-A}|@option{-o}|@option{--print-file-name}]
806 [@option{-a}|@option{--debug-syms}]
807 [@option{-B}|@option{--format=bsd}]
808 [@option{-C}|@option{--demangle}[=@var{style}]]
809 [@option{-D}|@option{--dynamic}]
810 [@option{-f}@var{format}|@option{--format=}@var{format}]
811 [@option{-g}|@option{--extern-only}]
812 [@option{-h}|@option{--help}]
813 [@option{--ifunc-chars=@var{CHARS}}]
814 [@option{-j}|@option{--format=just-symbols}]
815 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
816 [@option{-n}|@option{-v}|@option{--numeric-sort}]
817 [@option{-P}|@option{--portability}]
818 [@option{-p}|@option{--no-sort}]
819 [@option{-r}|@option{--reverse-sort}]
820 [@option{-S}|@option{--print-size}]
821 [@option{-s}|@option{--print-armap}]
822 [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
823 [@option{-u}|@option{--undefined-only}]
824 [@option{-U}|@option{--defined-only}]
825 [@option{-V}|@option{--version}]
826 [@option{-W}|@option{--no-weak}]
827 [@option{-X 32_64}]
828 [@option{--no-demangle}]
829 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
830 [@option{--plugin} @var{name}]
831 [@option{--size-sort}]
832 [@option{--special-syms}]
833 [@option{--synthetic}]
834 [@option{--target=}@var{bfdname}]
835 [@option{--unicode=}@var{method}]
836 [@option{--with-symbol-versions}]
837 [@option{--without-symbol-versions}]
838 [@var{objfile}@dots{}]
839@c man end
840@end smallexample
841
842@c man begin DESCRIPTION nm
843@sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
844If no object files are listed as arguments, @command{nm} assumes the file
845@file{a.out}.
846
847For each symbol, @command{nm} shows:
848
849@itemize @bullet
850@item
851The symbol value, in the radix selected by options (see below), or
852hexadecimal by default.
853
854@item
855The symbol type. At least the following types are used; others are, as
856well, depending on the object file format. If lowercase, the symbol is
857usually local; if uppercase, the symbol is global (external). There
858are however a few lowercase symbols that are shown for special global
859symbols (@code{u}, @code{v} and @code{w}).
860
861@c Some more detail on exactly what these symbol types are used for
862@c would be nice.
863@table @code
864@item A
865The symbol's value is absolute, and will not be changed by further
866linking.
867
868@item B
869@itemx b
870The symbol is in the BSS data section. This section typically
871contains zero-initialized or uninitialized data, although the exact
872behavior is system dependent.
873
874@item C
875@itemx c
876The symbol is common. Common symbols are uninitialized data. When
877linking, multiple common symbols may appear with the same name. If the
878symbol is defined anywhere, the common symbols are treated as undefined
879references.
880@ifclear man
881For more details on common symbols, see the discussion of
882--warn-common in @ref{Options,,Linker options,ld,The GNU linker}.
883@end ifclear
884The lower case @var{c} character is used when the symbol is in a
885special section for small commons.
886
887@item D
888@itemx d
889The symbol is in the initialized data section.
890
891@item G
892@itemx g
893The symbol is in an initialized data section for small objects. Some
894object file formats permit more efficient access to small data objects,
895such as a global int variable as opposed to a large global array.
896
897@item i
898For PE format files this indicates that the symbol is in a section
899specific to the implementation of DLLs.
900
901For ELF format files this indicates that the symbol is an indirect
902function. This is a GNU extension to the standard set of ELF symbol
903types. It indicates a symbol which if referenced by a relocation does
904not evaluate to its address, but instead must be invoked at runtime.
905The runtime execution will then return the value to be used in the
906relocation.
907
908Note - the actual symbols display for GNU indirect symbols is
909controlled by the @option{--ifunc-chars} command line option. If this
910option has been provided then the first character in the string will
911be used for global indirect function symbols. If the string contains
912a second character then that will be used for local indirect function
913symbols.
914
915@item I
916The symbol is an indirect reference to another symbol.
917
918@item N
919The symbol is a debugging symbol.
920
921@item n
922The symbol is in a non-data, non-code, non-debug read-only section.
923
924@item p
925The symbol is in a stack unwind section.
926
927@item R
928@itemx r
929The symbol is in a read only data section.
930
931@item S
932@itemx s
933The symbol is in an uninitialized or zero-initialized data section
934for small objects.
935
936@item T
937@itemx t
938The symbol is in the text (code) section.
939
940@item U
941The symbol is undefined.
942
943@item u
944The symbol is a unique global symbol. This is a GNU extension to the
945standard set of ELF symbol bindings. For such a symbol the dynamic linker
946will make sure that in the entire process there is just one symbol with
947this name and type in use.
948
949@item V
950@itemx v
951The symbol is a weak object. When a weak defined symbol is linked with
952a normal defined symbol, the normal defined symbol is used with no error.
953When a weak undefined symbol is linked and the symbol is not defined,
954the value of the weak symbol becomes zero with no error. On some
955systems, uppercase indicates that a default value has been specified.
956
957@item W
958@itemx w
959The symbol is a weak symbol that has not been specifically tagged as a
960weak object symbol. When a weak defined symbol is linked with a normal
961defined symbol, the normal defined symbol is used with no error.
962When a weak undefined symbol is linked and the symbol is not defined,
963the value of the symbol is determined in a system-specific manner without
964error. On some systems, uppercase indicates that a default value has been
965specified.
966
967@item -
968The symbol is a stabs symbol in an a.out object file. In this case, the
969next values printed are the stabs other field, the stabs desc field, and
970the stab type. Stabs symbols are used to hold debugging information.
971
972@item ?
973The symbol type is unknown, or object file format specific.
974@end table
975
976@item
977The symbol name. If a symbol has version information associated with it,
978then the version information is displayed as well. If the versioned
979symbol is undefined or hidden from linker, the version string is displayed
980as a suffix to the symbol name, preceded by an @@ character. For example
981@samp{foo@@VER_1}. If the version is the default version to be used when
982resolving unversioned references to the symbol, then it is displayed as a
983suffix preceded by two @@ characters. For example @samp{foo@@@@VER_2}.
984@end itemize
985
986@c man end
987
988@c man begin OPTIONS nm
989The long and short forms of options, shown here as alternatives, are
990equivalent.
991
992@table @env
993@item -A
994@itemx -o
995@itemx --print-file-name
996@cindex input file name
997@cindex file name
998@cindex source file name
999Precede each symbol by the name of the input file (or archive member)
1000in which it was found, rather than identifying the input file once only,
1001before all of its symbols.
1002
1003@item -a
1004@itemx --debug-syms
1005@cindex debugging symbols
1006Display all symbols, even debugger-only symbols; normally these are not
1007listed.
1008
1009@item -B
1010@cindex @command{nm} format
1011@cindex @command{nm} compatibility
1012The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
1013
1014@item -C
1015@itemx --demangle[=@var{style}]
1016@cindex demangling in nm
1017Decode (@dfn{demangle}) low-level symbol names into user-level names.
1018Besides removing any initial underscore prepended by the system, this
1019makes C++ function names readable. Different compilers have different
1020mangling styles. The optional demangling style argument can be used to
1021choose an appropriate demangling style for your compiler. @xref{c++filt},
1022for more information on demangling.
1023
1024@item --no-demangle
1025Do not demangle low-level symbol names. This is the default.
1026
1027@item --recurse-limit
1028@itemx --no-recurse-limit
1029@itemx --recursion-limit
1030@itemx --no-recursion-limit
1031Enables or disables a limit on the amount of recursion performed
1032whilst demangling strings. Since the name mangling formats allow for
1033an infinite level of recursion it is possible to create strings whose
1034decoding will exhaust the amount of stack space available on the host
1035machine, triggering a memory fault. The limit tries to prevent this
1036from happening by restricting recursion to 2048 levels of nesting.
1037
1038The default is for this limit to be enabled, but disabling it may be
1039necessary in order to demangle truly complicated names. Note however
1040that if the recursion limit is disabled then stack exhaustion is
1041possible and any bug reports about such an event will be rejected.
1042
1043@item -D
1044@itemx --dynamic
1045@cindex dynamic symbols
1046Display the dynamic symbols rather than the normal symbols. This is
1047only meaningful for dynamic objects, such as certain types of shared
1048libraries.
1049
1050@item -f @var{format}
1051@itemx --format=@var{format}
1052@cindex @command{nm} format
1053@cindex @command{nm} compatibility
1054Use the output format @var{format}, which can be @code{bsd},
1055@code{sysv}, @code{posix} or @code{just-symbols}. The default is @code{bsd}.
1056Only the first character of @var{format} is significant; it can be
1057either upper or lower case.
1058
1059@item -g
1060@itemx --extern-only
1061@cindex external symbols
1062Display only external symbols.
1063
1064@item -h
1065@itemx --help
1066Show a summary of the options to @command{nm} and exit.
1067
1068@item --ifunc-chars=@var{CHARS}
1069When display GNU indirect function symbols @command{nm} will default
1070to using the @code{i} character for both local indirect functions and
1071global indirect functions. The @option{--ifunc-chars} option allows
1072the user to specify a string containing one or two characters. The
1073first character will be used for global indirect function symbols and
1074the second character, if present, will be used for local indirect
1075function symbols.
1076
1077@item j
1078The same as @option{--format=just-symbols}.
1079
1080@item -l
1081@itemx --line-numbers
1082@cindex symbol line numbers
1083For each symbol, use debugging information to try to find a filename and
1084line number. For a defined symbol, look for the line number of the
1085address of the symbol. For an undefined symbol, look for the line
1086number of a relocation entry which refers to the symbol. If line number
1087information can be found, print it after the other symbol information.
1088
1089@item --inlines
1090@cindex objdump inlines
1091When option @option{-l} is active, if the address belongs to a
1092function that was inlined, then this option causes the source
1093information for all enclosing scopes back to the first non-inlined
1094function to be printed as well. For example, if @code{main} inlines
1095@code{callee1} which inlines @code{callee2}, and address is from
1096@code{callee2}, the source information for @code{callee1} and @code{main}
1097will also be printed.
1098
1099@item -n
1100@itemx -v
1101@itemx --numeric-sort
1102Sort symbols numerically by their addresses, rather than alphabetically
1103by their names.
1104
1105@item -p
1106@itemx --no-sort
1107@cindex sorting symbols
1108Do not bother to sort the symbols in any order; print them in the order
1109encountered.
1110
1111@item -P
1112@itemx --portability
1113Use the POSIX.2 standard output format instead of the default format.
1114Equivalent to @samp{-f posix}.
1115
1116@item -r
1117@itemx --reverse-sort
1118Reverse the order of the sort (whether numeric or alphabetic); let the
1119last come first.
1120
1121@item -S
1122@itemx --print-size
1123Print both value and size of defined symbols for the @code{bsd} output style.
1124This option has no effect for object formats that do not record symbol
1125sizes, unless @samp{--size-sort} is also used in which case a
1126calculated size is displayed.
1127
1128@item -s
1129@itemx --print-armap
1130@cindex symbol index, listing
1131When listing symbols from archive members, include the index: a mapping
1132(stored in the archive by @command{ar} or @command{ranlib}) of which modules
1133contain definitions for which names.
1134
1135@item -t @var{radix}
1136@itemx --radix=@var{radix}
1137Use @var{radix} as the radix for printing the symbol values. It must be
1138@samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1139
1140@item -u
1141@itemx --undefined-only
1142@cindex external symbols
1143@cindex undefined symbols
1144Display only undefined symbols (those external to each object file).
1145By default both defined and undefined symbols are displayed.
1146
1147@item -U
1148@itemx --defined-only
1149@cindex external symbols
1150@cindex undefined symbols
1151Display only defined symbols for each object file.
1152By default both defined and undefined symbols are displayed.
1153
1154@item -V
1155@itemx --version
1156Show the version number of @command{nm} and exit.
1157
1158@item -X
1159This option is ignored for compatibility with the AIX version of
1160@command{nm}. It takes one parameter which must be the string
1161@option{32_64}. The default mode of AIX @command{nm} corresponds
1162to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1163
1164@item --plugin @var{name}
1165@cindex plugins
1166Load the plugin called @var{name} to add support for extra target
1167types. This option is only available if the toolchain has been built
1168with plugin support enabled.
1169
1170If @option{--plugin} is not provided, but plugin support has been
1171enabled then @command{nm} iterates over the files in
1172@file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1173plugin that claims the object in question is used.
1174
1175Please note that this plugin search directory is @emph{not} the one
1176used by @command{ld}'s @option{-plugin} option. In order to make
1177@command{nm} use the linker plugin it must be copied into the
1178@file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1179the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1180based compilations it is called @file{LLVMgold.so}. The GCC plugin
1181is always backwards compatible with earlier versions, so it is
1182sufficient to just copy the newest one.
1183
1184@item --size-sort
1185Sort symbols by size. For ELF objects symbol sizes are read from the
1186ELF, for other object types the symbol sizes are computed as the
1187difference between the value of the symbol and the value of the symbol
1188with the next higher value. If the @code{bsd} output format is used
1189the size of the symbol is printed, rather than the value, and
1190@samp{-S} must be used in order both size and value to be printed.
1191
1192Note - this option does not work if @option{--undefined-only} has been
1193enabled as undefined symbols have no size.
1194
1195@item --special-syms
1196Display symbols which have a target-specific special meaning. These
1197symbols are usually used by the target for some special processing and
1198are not normally helpful when included in the normal symbol lists.
1199For example for ARM targets this option would skip the mapping symbols
1200used to mark transitions between ARM code, THUMB code and data.
1201
1202@item --synthetic
1203Include synthetic symbols in the output. These are special symbols
1204created by the linker for various purposes. They are not shown by
1205default since they are not part of the binary's original source code.
1206
1207@item --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
1208Controls the display of UTF-8 encoded multibyte characters in strings.
1209The default (@option{--unicode=default}) is to give them no special
1210treatment. The @option{--unicode=locale} option displays the sequence
1211in the current locale, which may or may not support them. The options
1212@option{--unicode=hex} and @option{--unicode=invalid} display them as
1213hex byte sequences enclosed by either angle brackets or curly braces.
1214
1215The @option{--unicode=escape} option displays them as escape sequences
1216(@var{\uxxxx}) and the @option{--unicode=highlight} option displays
1217them as escape sequences highlighted in red (if supported by the
1218output device). The colouring is intended to draw attention to the
1219presence of unicode sequences where they might not be expected.
1220
1221@item -W
1222@itemx --no-weak
1223Do not display weak symbols.
1224
1225@item --with-symbol-versions
1226@item --without-symbol-versions
1227Enables or disables the display of symbol version information. The
1228version string is displayed as a suffix to the symbol name, preceded
1229by an @@ character. For example @samp{foo@@VER_1}. If the version is
1230the default version to be used when resolving unversioned references
1231to the symbol then it is displayed as a suffix preceded by two @@
1232characters. For example @samp{foo@@@@VER_2}. By default, symbol
1233version information is displayed.
1234
1235@item --target=@var{bfdname}
1236@cindex object code format
1237Specify an object code format other than your system's default format.
1238@xref{Target Selection}, for more information.
1239
1240@end table
1241
1242@c man end
1243
1244@ignore
1245@c man begin SEEALSO nm
1246ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1247@c man end
1248@end ignore
1249
1250@node objcopy
1251@chapter objcopy
1252
1253@c man title objcopy copy and translate object files
1254
1255@smallexample
1256@c man begin SYNOPSIS objcopy
1257objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1258 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1259 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1260 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1261 [@option{-S}|@option{--strip-all}]
1262 [@option{-g}|@option{--strip-debug}]
1263 [@option{--strip-unneeded}]
1264 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1265 [@option{--keep-file-symbols}]
1266 [@option{--keep-section-symbols}]
1267 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1268 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1269 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1270 [@option{--localize-hidden}]
1271 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1272 [@option{--globalize-symbol=}@var{symbolname}]
1273 [@option{--globalize-symbols=}@var{filename}]
1274 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1275 [@option{-w}|@option{--wildcard}]
1276 [@option{-x}|@option{--discard-all}]
1277 [@option{-X}|@option{--discard-locals}]
1278 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1279 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1280 [@option{--interleave-width=}@var{width}]
1281 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1282 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1283 [@option{--keep-section=}@var{sectionpattern}]
1284 [@option{--remove-relocations=}@var{sectionpattern}]
1285 [@option{--strip-section-headers}]
1286 [@option{-p}|@option{--preserve-dates}]
1287 [@option{-D}|@option{--enable-deterministic-archives}]
1288 [@option{-U}|@option{--disable-deterministic-archives}]
1289 [@option{--debugging}]
1290 [@option{--gap-fill=}@var{val}]
1291 [@option{--pad-to=}@var{address}]
1292 [@option{--set-start=}@var{val}]
1293 [@option{--adjust-start=}@var{incr}]
1294 [@option{--change-addresses=}@var{incr}]
1295 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1296 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1297 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1298 [@option{--change-warnings}] [@option{--no-change-warnings}]
1299 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1300 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1301 [@option{--add-section} @var{sectionname}=@var{filename}]
1302 [@option{--dump-section} @var{sectionname}=@var{filename}]
1303 [@option{--update-section} @var{sectionname}=@var{filename}]
1304 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1305 [@option{--long-section-names} @{enable,disable,keep@}]
1306 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1307 [@option{--reverse-bytes=}@var{num}]
1308 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1309 [@option{--redefine-sym} @var{old}=@var{new}]
1310 [@option{--redefine-syms=}@var{filename}]
1311 [@option{--weaken}]
1312 [@option{--keep-symbols=}@var{filename}]
1313 [@option{--strip-symbols=}@var{filename}]
1314 [@option{--strip-unneeded-symbols=}@var{filename}]
1315 [@option{--keep-global-symbols=}@var{filename}]
1316 [@option{--localize-symbols=}@var{filename}]
1317 [@option{--weaken-symbols=}@var{filename}]
1318 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1319 [@option{--alt-machine-code=}@var{index}]
1320 [@option{--prefix-symbols=}@var{string}]
1321 [@option{--prefix-sections=}@var{string}]
1322 [@option{--prefix-alloc-sections=}@var{string}]
1323 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1324 [@option{--only-keep-debug}]
1325 [@option{--strip-dwo}]
1326 [@option{--extract-dwo}]
1327 [@option{--extract-symbol}]
1328 [@option{--writable-text}]
1329 [@option{--readonly-text}]
1330 [@option{--pure}]
1331 [@option{--impure}]
1332 [@option{--file-alignment=}@var{num}]
1333 [@option{--heap=}@var{reserve}[,@var{commit}]]
1334 [@option{--image-base=}@var{address}]
1335 [@option{--section-alignment=}@var{num}]
1336 [@option{--stack=}@var{reserve}[,@var{commit}]]
1337 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1338 [@option{--compress-debug-sections}]
1339 [@option{--decompress-debug-sections}]
1340 [@option{--elf-stt-common=@var{val}}]
1341 [@option{--merge-notes}]
1342 [@option{--no-merge-notes}]
1343 [@option{--verilog-data-width=@var{val}}]
1344 [@option{-v}|@option{--verbose}]
1345 [@option{-V}|@option{--version}]
1346 [@option{--help}] [@option{--info}]
1347 @var{infile} [@var{outfile}]
1348@c man end
1349@end smallexample
1350
1351@c man begin DESCRIPTION objcopy
1352The @sc{gnu} @command{objcopy} utility copies the contents of an object
1353file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1354read and write the object files. It can write the destination object
1355file in a format different from that of the source object file. The
1356exact behavior of @command{objcopy} is controlled by command-line options.
1357Note that @command{objcopy} should be able to copy a fully linked file
1358between any two formats. However, copying a relocatable object file
1359between any two formats may not work as expected.
1360
1361@command{objcopy} creates temporary files to do its translations and
1362deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1363translation work; it has access to all the formats described in @sc{bfd}
1364and thus is able to recognize most formats without being told
1365explicitly. @xref{BFD,,BFD,ld,Using LD}.
1366
1367@command{objcopy} can be used to generate S-records by using an output
1368target of @samp{srec} (e.g., use @samp{-O srec}).
1369
1370@command{objcopy} can be used to generate a raw binary file by using an
1371output target of @samp{binary} (e.g., use @option{-O binary}). When
1372@command{objcopy} generates a raw binary file, it will essentially produce
1373a memory dump of the contents of the input object file. All symbols and
1374relocation information will be discarded. The memory dump will start at
1375the load address of the lowest section copied into the output file.
1376
1377When generating an S-record or a raw binary file, it may be helpful to
1378use @option{-S} to remove sections containing debugging information. In
1379some cases @option{-R} will be useful to remove sections which contain
1380information that is not needed by the binary file.
1381
1382Note---@command{objcopy} is not able to change the endianness of its input
1383files. If the input format has an endianness (some formats do not),
1384@command{objcopy} can only copy the inputs into file formats that have the
1385same endianness or which have no endianness (e.g., @samp{srec}).
1386(However, see the @option{--reverse-bytes} option.)
1387
1388@c man end
1389
1390@c man begin OPTIONS objcopy
1391
1392@table @env
1393@item @var{infile}
1394@itemx @var{outfile}
1395The input and output files, respectively.
1396If you do not specify @var{outfile}, @command{objcopy} creates a
1397temporary file and destructively renames the result with
1398the name of @var{infile}.
1399
1400@item -I @var{bfdname}
1401@itemx --input-target=@var{bfdname}
1402Consider the source file's object format to be @var{bfdname}, rather than
1403attempting to deduce it. @xref{Target Selection}, for more information.
1404
1405@item -O @var{bfdname}
1406@itemx --output-target=@var{bfdname}
1407Write the output file using the object format @var{bfdname}.
1408@xref{Target Selection}, for more information.
1409
1410@item -F @var{bfdname}
1411@itemx --target=@var{bfdname}
1412Use @var{bfdname} as the object format for both the input and the output
1413file; i.e., simply transfer data from source to destination with no
1414translation. @xref{Target Selection}, for more information.
1415
1416@item -B @var{bfdarch}
1417@itemx --binary-architecture=@var{bfdarch}
1418Useful when transforming a architecture-less input file into an object file.
1419In this case the output architecture can be set to @var{bfdarch}. This
1420option will be ignored if the input file has a known @var{bfdarch}. You
1421can access this binary data inside a program by referencing the special
1422symbols that are created by the conversion process. These symbols are
1423called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1424_binary_@var{objfile}_size. e.g. you can transform a picture file into
1425an object file and then access it in your code using these symbols.
1426
1427@item -j @var{sectionpattern}
1428@itemx --only-section=@var{sectionpattern}
1429Copy only the indicated sections from the input file to the output file.
1430This option may be given more than once. Note that using this option
1431inappropriately may make the output file unusable. Wildcard
1432characters are accepted in @var{sectionpattern}.
1433
1434If the first character of @var{sectionpattern} is the exclamation
1435point (!) then matching sections will not be copied, even if earlier
1436use of @option{--only-section} on the same command line would
1437otherwise copy it. For example:
1438
1439@smallexample
1440 --only-section=.text.* --only-section=!.text.foo
1441@end smallexample
1442
1443will copy all sectinos matching '.text.*' but not the section
1444'.text.foo'.
1445
1446@item -R @var{sectionpattern}
1447@itemx --remove-section=@var{sectionpattern}
1448Remove any section matching @var{sectionpattern} from the output file.
1449This option may be given more than once. Note that using this option
1450inappropriately may make the output file unusable. Wildcard
1451characters are accepted in @var{sectionpattern}. Using both the
1452@option{-j} and @option{-R} options together results in undefined
1453behaviour.
1454
1455If the first character of @var{sectionpattern} is the exclamation
1456point (!) then matching sections will not be removed even if an
1457earlier use of @option{--remove-section} on the same command line
1458would otherwise remove it. For example:
1459
1460@smallexample
1461 --remove-section=.text.* --remove-section=!.text.foo
1462@end smallexample
1463
1464will remove all sections matching the pattern '.text.*', but will not
1465remove the section '.text.foo'.
1466
1467@item --keep-section=@var{sectionpattern}
1468When removing sections from the output file, keep sections that match
1469@var{sectionpattern}.
1470
1471@item --remove-relocations=@var{sectionpattern}
1472Remove non-dynamic relocations from the output file for any section
1473matching @var{sectionpattern}. This option may be given more than
1474once. Note that using this option inappropriately may make the output
1475file unusable, and attempting to remove a dynamic relocation section
1476such as @samp{.rela.plt} from an executable or shared library with
1477@option{--remove-relocations=.plt} will not work. Wildcard characters
1478are accepted in @var{sectionpattern}.
1479For example:
1480
1481@smallexample
1482 --remove-relocations=.text.*
1483@end smallexample
1484
1485will remove the relocations for all sections matching the pattern
1486'.text.*'.
1487
1488If the first character of @var{sectionpattern} is the exclamation
1489point (!) then matching sections will not have their relocation
1490removed even if an earlier use of @option{--remove-relocations} on the
1491same command line would otherwise cause the relocations to be removed.
1492For example:
1493
1494@smallexample
1495 --remove-relocations=.text.* --remove-relocations=!.text.foo
1496@end smallexample
1497
1498will remove all relocations for sections matching the pattern
1499'.text.*', but will not remove relocations for the section
1500'.text.foo'.
1501
1502@item --strip-section-headers
1503Strip section header This option is specific to ELF files.
1504Implies @option{--strip-all} and @option{--merge-notes}.
1505
1506@item -S
1507@itemx --strip-all
1508Do not copy relocation and symbol information from the source file.
1509Also deletes debug sections.
1510
1511@item -g
1512@itemx --strip-debug
1513Do not copy debugging symbols or sections from the source file.
1514
1515@item --strip-unneeded
1516Remove all symbols that are not needed for relocation processing in
1517addition to debugging symbols and sections stripped by
1518@option{--strip-debug}.
1519
1520@item -K @var{symbolname}
1521@itemx --keep-symbol=@var{symbolname}
1522When stripping symbols, keep symbol @var{symbolname} even if it would
1523normally be stripped. This option may be given more than once.
1524
1525@item -N @var{symbolname}
1526@itemx --strip-symbol=@var{symbolname}
1527Do not copy symbol @var{symbolname} from the source file. This option
1528may be given more than once.
1529
1530@item --strip-unneeded-symbol=@var{symbolname}
1531Do not copy symbol @var{symbolname} from the source file unless it is needed
1532by a relocation. This option may be given more than once.
1533
1534@item -G @var{symbolname}
1535@itemx --keep-global-symbol=@var{symbolname}
1536Keep only symbol @var{symbolname} global. Make all other symbols local
1537to the file, so that they are not visible externally. This option may
1538be given more than once. Note: this option cannot be used in
1539conjunction with the @option{--globalize-symbol} or
1540@option{--globalize-symbols} options.
1541
1542@item --localize-hidden
1543In an ELF object, mark all symbols that have hidden or internal visibility
1544as local. This option applies on top of symbol-specific localization options
1545such as @option{-L}.
1546
1547@item -L @var{symbolname}
1548@itemx --localize-symbol=@var{symbolname}
1549Convert a global or weak symbol called @var{symbolname} into a local
1550symbol, so that it is not visible externally. This option may be
1551given more than once. Note - unique symbols are not converted.
1552
1553@item -W @var{symbolname}
1554@itemx --weaken-symbol=@var{symbolname}
1555Make symbol @var{symbolname} weak. This option may be given more than once.
1556
1557@item --globalize-symbol=@var{symbolname}
1558Give symbol @var{symbolname} global scoping so that it is visible
1559outside of the file in which it is defined. This option may be given
1560more than once. Note: this option cannot be used in conjunction with
1561the @option{-G} or @option{--keep-global-symbol} options.
1562
1563@item -w
1564@itemx --wildcard
1565Permit regular expressions in @var{symbolname}s used in other command
1566line options. The question mark (?), asterisk (*), backslash (\) and
1567square brackets ([]) operators can be used anywhere in the symbol
1568name. If the first character of the symbol name is the exclamation
1569point (!) then the sense of the switch is reversed for that symbol.
1570For example:
1571
1572@smallexample
1573 -w -W !foo -W fo*
1574@end smallexample
1575
1576would cause objcopy to weaken all symbols that start with ``fo''
1577except for the symbol ``foo''.
1578
1579@item -x
1580@itemx --discard-all
1581Do not copy non-global symbols from the source file.
1582@c FIXME any reason to prefer "non-global" to "local" here?
1583
1584@item -X
1585@itemx --discard-locals
1586Do not copy compiler-generated local symbols.
1587(These usually start with @samp{L} or @samp{.}.)
1588
1589@item -b @var{byte}
1590@itemx --byte=@var{byte}
1591If interleaving has been enabled via the @option{--interleave} option
1592then start the range of bytes to keep at the @var{byte}th byte.
1593@var{byte} can be in the range from 0 to @var{breadth}-1, where
1594@var{breadth} is the value given by the @option{--interleave} option.
1595
1596@item -i [@var{breadth}]
1597@itemx --interleave[=@var{breadth}]
1598Only copy a range out of every @var{breadth} bytes. (Header data is
1599not affected). Select which byte in the range begins the copy with
1600the @option{--byte} option. Select the width of the range with the
1601@option{--interleave-width} option.
1602
1603This option is useful for creating files to program @sc{rom}. It is
1604typically used with an @code{srec} output target. Note that
1605@command{objcopy} will complain if you do not specify the
1606@option{--byte} option as well.
1607
1608The default interleave breadth is 4, so with @option{--byte} set to 0,
1609@command{objcopy} would copy the first byte out of every four bytes
1610from the input to the output.
1611
1612@item --interleave-width=@var{width}
1613When used with the @option{--interleave} option, copy @var{width}
1614bytes at a time. The start of the range of bytes to be copied is set
1615by the @option{--byte} option, and the extent of the range is set with
1616the @option{--interleave} option.
1617
1618The default value for this option is 1. The value of @var{width} plus
1619the @var{byte} value set by the @option{--byte} option must not exceed
1620the interleave breadth set by the @option{--interleave} option.
1621
1622This option can be used to create images for two 16-bit flashes interleaved
1623in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1624and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1625commands. If the input was '12345678' then the outputs would be
1626'1256' and '3478' respectively.
1627
1628@item -p
1629@itemx --preserve-dates
1630Set the access and modification dates of the output file to be the same
1631as those of the input file.
1632
1633This option also copies the date stored in a PE format file's header,
1634unless the SOURCE_DATE_EPOCH environment variable is defined. If it
1635is defined then this variable will be used as the date stored in the
1636header, interpreted as the number of seconds since the Unix epoch.
1637
1638@item -D
1639@itemx --enable-deterministic-archives
1640@cindex deterministic archives
1641@kindex --enable-deterministic-archives
1642Operate in @emph{deterministic} mode. When copying archive members
1643and writing the archive index, use zero for UIDs, GIDs, timestamps,
1644and use consistent file modes for all files.
1645
1646If @file{binutils} was configured with
1647@option{--enable-deterministic-archives}, then this mode is on by default.
1648It can be disabled with the @samp{-U} option, below.
1649
1650@item -U
1651@itemx --disable-deterministic-archives
1652@cindex deterministic archives
1653@kindex --enable-deterministic-archives
1654Do @emph{not} operate in @emph{deterministic} mode. This is the
1655inverse of the @option{-D} option, above: when copying archive members
1656and writing the archive index, use their actual UID, GID, timestamp,
1657and file mode values.
1658
1659This is the default unless @file{binutils} was configured with
1660@option{--enable-deterministic-archives}.
1661
1662@item --debugging
1663Convert debugging information, if possible. This is not the default
1664because only certain debugging formats are supported, and the
1665conversion process can be time consuming.
1666
1667@item --gap-fill @var{val}
1668Fill gaps between sections with @var{val}. This operation applies to
1669the @emph{load address} (LMA) of the sections. It is done by increasing
1670the size of the section with the lower address, and filling in the extra
1671space created with @var{val}.
1672
1673@item --pad-to @var{address}
1674Pad the output file up to the load address @var{address}. This is
1675done by increasing the size of the last section. The extra space is
1676filled in with the value specified by @option{--gap-fill} (default zero).
1677
1678@item --set-start @var{val}
1679Set the start address (also known as the entry address) of the new
1680file to @var{val}. Not all object file formats support setting the
1681start address.
1682
1683@item --change-start @var{incr}
1684@itemx --adjust-start @var{incr}
1685@cindex changing start address
1686Change the start address (also known as the entry address) by adding
1687@var{incr}. Not all object file formats support setting the start
1688address.
1689
1690@item --change-addresses @var{incr}
1691@itemx --adjust-vma @var{incr}
1692@cindex changing object addresses
1693Change the VMA and LMA addresses of all sections, as well as the start
1694address, by adding @var{incr}. Some object file formats do not permit
1695section addresses to be changed arbitrarily. Note that this does not
1696relocate the sections; if the program expects sections to be loaded at a
1697certain address, and this option is used to change the sections such
1698that they are loaded at a different address, the program may fail.
1699
1700@item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1701@itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1702@cindex changing section address
1703Set or change both the VMA address and the LMA address of any section
1704matching @var{sectionpattern}. If @samp{=} is used, the section
1705address is set to @var{val}. Otherwise, @var{val} is added to or
1706subtracted from the section address. See the comments under
1707@option{--change-addresses}, above. If @var{sectionpattern} does not
1708match any sections in the input file, a warning will be issued, unless
1709@option{--no-change-warnings} is used.
1710
1711@item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1712@cindex changing section LMA
1713Set or change the LMA address of any sections matching
1714@var{sectionpattern}. The LMA address is the address where the
1715section will be loaded into memory at program load time. Normally
1716this is the same as the VMA address, which is the address of the
1717section at program run time, but on some systems, especially those
1718where a program is held in ROM, the two can be different. If @samp{=}
1719is used, the section address is set to @var{val}. Otherwise,
1720@var{val} is added to or subtracted from the section address. See the
1721comments under @option{--change-addresses}, above. If
1722@var{sectionpattern} does not match any sections in the input file, a
1723warning will be issued, unless @option{--no-change-warnings} is used.
1724
1725@item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1726@cindex changing section VMA
1727Set or change the VMA address of any section matching
1728@var{sectionpattern}. The VMA address is the address where the
1729section will be located once the program has started executing.
1730Normally this is the same as the LMA address, which is the address
1731where the section will be loaded into memory, but on some systems,
1732especially those where a program is held in ROM, the two can be
1733different. If @samp{=} is used, the section address is set to
1734@var{val}. Otherwise, @var{val} is added to or subtracted from the
1735section address. See the comments under @option{--change-addresses},
1736above. If @var{sectionpattern} does not match any sections in the
1737input file, a warning will be issued, unless
1738@option{--no-change-warnings} is used.
1739
1740Note - changing the VMA of sections in a fully linked binary can be
1741dangerous since there may be code that expects the sections to be
1742located at their old address.
1743
1744@item --change-warnings
1745@itemx --adjust-warnings
1746If @option{--change-section-address} or @option{--change-section-lma} or
1747@option{--change-section-vma} is used, and the section pattern does not
1748match any sections, issue a warning. This is the default.
1749
1750@item --no-change-warnings
1751@itemx --no-adjust-warnings
1752Do not issue a warning if @option{--change-section-address} or
1753@option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1754if the section pattern does not match any sections.
1755
1756@item --set-section-flags @var{sectionpattern}=@var{flags}
1757Set the flags for any sections matching @var{sectionpattern}. The
1758@var{flags} argument is a comma separated string of flag names. The
1759recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1760@samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1761@samp{exclude}, @samp{share}, @samp{debug}, and @samp{large}.
1762You can set the @samp{contents} flag for a section which does not have
1763contents, but it is not meaningful to clear the @samp{contents} flag of a
1764section which does have contents--just remove the section instead. Not all
1765flags are meaningful for all object file formats. In particular the
1766@samp{share} flag is only meaningful for COFF format files and not for ELF
1767format files. The ELF x86-64 specific flag @samp{large} corresponds to
1768SHF_X86_64_LARGE.
1769
1770@item --set-section-alignment @var{sectionpattern}=@var{align}
1771Set the alignment for any sections matching @var{sectionpattern}.
1772@var{align} specifies the alignment in bytes and must be a power of
1773two, i.e. 1, 2, 4, 8@dots{}.
1774
1775Note - setting a section's alignment will not automatically align its
1776LMA or VMA addresses. If those need to be changed as well then the
1777@option{--change-section-lma} and/or @option{--change-section-vma}
1778options should be used. Also note that changing VMAs can cause
1779problems in fully linked binaries where there may be code that expects
1780the contents of the sections to be located at their old address.
1781
1782@item --add-section @var{sectionname}=@var{filename}
1783Add a new section named @var{sectionname} while copying the file. The
1784contents of the new section are taken from the file @var{filename}. The
1785size of the section will be the size of the file. This option only
1786works on file formats which can support sections with arbitrary names.
1787Note - it may be necessary to use the @option{--set-section-flags}
1788option to set the attributes of the newly created section.
1789
1790@item --dump-section @var{sectionname}=@var{filename}
1791Place the contents of section named @var{sectionname} into the file
1792@var{filename}, overwriting any contents that may have been there
1793previously. This option is the inverse of @option{--add-section}.
1794This option is similar to the @option{--only-section} option except
1795that it does not create a formatted file, it just dumps the contents
1796as raw binary data, without applying any relocations. The option can
1797be specified more than once.
1798
1799@item --update-section @var{sectionname}=@var{filename}
1800Replace the existing contents of a section named @var{sectionname}
1801with the contents of file @var{filename}. The size of the section
1802will be adjusted to the size of the file. The section flags for
1803@var{sectionname} will be unchanged. For ELF format files the section
1804to segment mapping will also remain unchanged, something which is not
1805possible using @option{--remove-section} followed by
1806@option{--add-section}. The option can be specified more than once.
1807
1808Note - it is possible to use @option{--rename-section} and
1809@option{--update-section} to both update and rename a section from one
1810command line. In this case, pass the original section name to
1811@option{--update-section}, and the original and new section names to
1812@option{--rename-section}.
1813
1814@item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1815Add a new symbol named @var{name} while copying the file. This option may be
1816specified multiple times. If the @var{section} is given, the symbol will be
1817associated with and relative to that section, otherwise it will be an ABS
1818symbol. Specifying an undefined section will result in a fatal error. There
1819is no check for the value, it will be taken as specified. Symbol flags can
1820be specified and not all flags will be meaningful for all object file
1821formats. By default, the symbol will be global. The special flag
1822'before=@var{othersym}' will insert the new symbol in front of the specified
1823@var{othersym}, otherwise the symbol(s) will be added at the end of the
1824symbol table in the order they appear.
1825
1826@item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1827Rename a section from @var{oldname} to @var{newname}, optionally
1828changing the section's flags to @var{flags} in the process. This has
1829the advantage over using a linker script to perform the rename in that
1830the output stays as an object file and does not become a linked
1831executable. This option accepts the same set of flags as the
1832@option{--set-section-flags} option.
1833
1834This option is particularly helpful when the input format is binary,
1835since this will always create a section called .data. If for example,
1836you wanted instead to create a section called .rodata containing binary
1837data you could use the following command line to achieve it:
1838
1839@smallexample
1840 objcopy -I binary -O <output_format> -B <architecture> \
1841 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1842 <input_binary_file> <output_object_file>
1843@end smallexample
1844
1845@item --long-section-names @{enable,disable,keep@}
1846Controls the handling of long section names when processing @code{COFF}
1847and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1848is to preserve long section names if any are present in the input file.
1849The @samp{enable} and @samp{disable} options forcibly enable or disable
1850the use of long section names in the output object; when @samp{disable}
1851is in effect, any long section names in the input object will be truncated.
1852The @samp{enable} option will only emit long section names if any are
1853present in the inputs; this is mostly the same as @samp{keep}, but it
1854is left undefined whether the @samp{enable} option might force the
1855creation of an empty string table in the output file.
1856
1857@item --change-leading-char
1858Some object file formats use special characters at the start of
1859symbols. The most common such character is underscore, which compilers
1860often add before every symbol. This option tells @command{objcopy} to
1861change the leading character of every symbol when it converts between
1862object file formats. If the object file formats use the same leading
1863character, this option has no effect. Otherwise, it will add a
1864character, or remove a character, or change a character, as
1865appropriate.
1866
1867@item --remove-leading-char
1868If the first character of a global symbol is a special symbol leading
1869character used by the object file format, remove the character. The
1870most common symbol leading character is underscore. This option will
1871remove a leading underscore from all global symbols. This can be useful
1872if you want to link together objects of different file formats with
1873different conventions for symbol names. This is different from
1874@option{--change-leading-char} because it always changes the symbol name
1875when appropriate, regardless of the object file format of the output
1876file.
1877
1878@item --reverse-bytes=@var{num}
1879Reverse the bytes in a section with output contents. A section length must
1880be evenly divisible by the value given in order for the swap to be able to
1881take place. Reversing takes place before the interleaving is performed.
1882
1883This option is used typically in generating ROM images for problematic
1884target systems. For example, on some target boards, the 32-bit words
1885fetched from 8-bit ROMs are re-assembled in little-endian byte order
1886regardless of the CPU byte order. Depending on the programming model, the
1887endianness of the ROM may need to be modified.
1888
1889Consider a simple file with a section containing the following eight
1890bytes: @code{12345678}.
1891
1892Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1893output file would be ordered @code{21436587}.
1894
1895Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1896output file would be ordered @code{43218765}.
1897
1898By using @samp{--reverse-bytes=2} for the above example, followed by
1899@samp{--reverse-bytes=4} on the output file, the bytes in the second
1900output file would be ordered @code{34127856}.
1901
1902@item --srec-len=@var{ival}
1903Meaningful only for srec output. Set the maximum length of the Srecords
1904being produced to @var{ival}. This length covers both address, data and
1905crc fields.
1906
1907@item --srec-forceS3
1908Meaningful only for srec output. Avoid generation of S1/S2 records,
1909creating S3-only record format.
1910
1911@item --redefine-sym @var{old}=@var{new}
1912Change the name of a symbol @var{old}, to @var{new}. This can be useful
1913when one is trying link two things together for which you have no
1914source, and there are name collisions.
1915
1916@item --redefine-syms=@var{filename}
1917Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1918listed in the file @var{filename}. @var{filename} is simply a flat file,
1919with one symbol pair per line. Line comments may be introduced by the hash
1920character. This option may be given more than once.
1921
1922@item --weaken
1923Change all global symbols in the file to be weak. This can be useful
1924when building an object which will be linked against other objects using
1925the @option{-R} option to the linker. This option is only effective when
1926using an object file format which supports weak symbols.
1927
1928@item --keep-symbols=@var{filename}
1929Apply @option{--keep-symbol} option to each symbol listed in the file
1930@var{filename}. @var{filename} is simply a flat file, with one symbol
1931name per line. Line comments may be introduced by the hash character.
1932This option may be given more than once.
1933
1934@item --strip-symbols=@var{filename}
1935Apply @option{--strip-symbol} option to each symbol listed in the file
1936@var{filename}. @var{filename} is simply a flat file, with one symbol
1937name per line. Line comments may be introduced by the hash character.
1938This option may be given more than once.
1939
1940@item --strip-unneeded-symbols=@var{filename}
1941Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1942the file @var{filename}. @var{filename} is simply a flat file, with one
1943symbol name per line. Line comments may be introduced by the hash
1944character. This option may be given more than once.
1945
1946@item --keep-global-symbols=@var{filename}
1947Apply @option{--keep-global-symbol} option to each symbol listed in the
1948file @var{filename}. @var{filename} is simply a flat file, with one
1949symbol name per line. Line comments may be introduced by the hash
1950character. This option may be given more than once.
1951
1952@item --localize-symbols=@var{filename}
1953Apply @option{--localize-symbol} option to each symbol listed in the file
1954@var{filename}. @var{filename} is simply a flat file, with one symbol
1955name per line. Line comments may be introduced by the hash character.
1956This option may be given more than once.
1957
1958@item --globalize-symbols=@var{filename}
1959Apply @option{--globalize-symbol} option to each symbol listed in the file
1960@var{filename}. @var{filename} is simply a flat file, with one symbol
1961name per line. Line comments may be introduced by the hash character.
1962This option may be given more than once. Note: this option cannot be
1963used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1964options.
1965
1966@item --weaken-symbols=@var{filename}
1967Apply @option{--weaken-symbol} option to each symbol listed in the file
1968@var{filename}. @var{filename} is simply a flat file, with one symbol
1969name per line. Line comments may be introduced by the hash character.
1970This option may be given more than once.
1971
1972@item --alt-machine-code=@var{index}
1973If the output architecture has alternate machine codes, use the
1974@var{index}th code instead of the default one. This is useful in case
1975a machine is assigned an official code and the tool-chain adopts the
1976new code, but other applications still depend on the original code
1977being used. For ELF based architectures if the @var{index}
1978alternative does not exist then the value is treated as an absolute
1979number to be stored in the e_machine field of the ELF header.
1980
1981@item --writable-text
1982Mark the output text as writable. This option isn't meaningful for all
1983object file formats.
1984
1985@item --readonly-text
1986Make the output text write protected. This option isn't meaningful for all
1987object file formats.
1988
1989@item --pure
1990Mark the output file as demand paged. This option isn't meaningful for all
1991object file formats.
1992
1993@item --impure
1994Mark the output file as impure. This option isn't meaningful for all
1995object file formats.
1996
1997@item --prefix-symbols=@var{string}
1998Prefix all symbols in the output file with @var{string}.
1999
2000@item --prefix-sections=@var{string}
2001Prefix all section names in the output file with @var{string}.
2002
2003@item --prefix-alloc-sections=@var{string}
2004Prefix all the names of all allocated sections in the output file with
2005@var{string}.
2006
2007@item --add-gnu-debuglink=@var{path-to-file}
2008Creates a .gnu_debuglink section which contains a reference to
2009@var{path-to-file} and adds it to the output file. Note: the file at
2010@var{path-to-file} must exist. Part of the process of adding the
2011.gnu_debuglink section involves embedding a checksum of the contents
2012of the debug info file into the section.
2013
2014If the debug info file is built in one location but it is going to be
2015installed at a later time into a different location then do not use
2016the path to the installed location. The @option{--add-gnu-debuglink}
2017option will fail because the installed file does not exist yet.
2018Instead put the debug info file in the current directory and use the
2019@option{--add-gnu-debuglink} option without any directory components,
2020like this:
2021
2022@smallexample
2023 objcopy --add-gnu-debuglink=foo.debug
2024@end smallexample
2025
2026At debug time the debugger will attempt to look for the separate debug
2027info file in a set of known locations. The exact set of these
2028locations varies depending upon the distribution being used, but it
2029typically includes:
2030
2031@table @code
2032
2033@item * The same directory as the executable.
2034
2035@item * A sub-directory of the directory containing the executable
2036called .debug
2037
2038@item * A global debug directory such as /usr/lib/debug.
2039@end table
2040
2041As long as the debug info file has been installed into one of these
2042locations before the debugger is run everything should work
2043correctly.
2044
2045@item --keep-section-symbols
2046When stripping a file, perhaps with @option{--strip-debug} or
2047@option{--strip-unneeded}, retain any symbols specifying section names,
2048which would otherwise get stripped.
2049
2050@item --keep-file-symbols
2051When stripping a file, perhaps with @option{--strip-debug} or
2052@option{--strip-unneeded}, retain any symbols specifying source file names,
2053which would otherwise get stripped.
2054
2055@item --only-keep-debug
2056Strip a file, removing contents of any sections that would not be
2057stripped by @option{--strip-debug} and leaving the debugging sections
2058intact. In ELF files, this preserves all note sections in the output.
2059
2060Note - the section headers of the stripped sections are preserved,
2061including their sizes, but the contents of the section are discarded.
2062The section headers are preserved so that other tools can match up the
2063debuginfo file with the real executable, even if that executable has
2064been relocated to a different address space.
2065
2066The intention is that this option will be used in conjunction with
2067@option{--add-gnu-debuglink} to create a two part executable. One a
2068stripped binary which will occupy less space in RAM and in a
2069distribution and the second a debugging information file which is only
2070needed if debugging abilities are required. The suggested procedure
2071to create these files is as follows:
2072
2073@enumerate
2074@item Link the executable as normal. Assuming that it is called
2075@code{foo} then...
2076@item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2077create a file containing the debugging info.
2078@item Run @code{objcopy --strip-debug foo} to create a
2079stripped executable.
2080@item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2081to add a link to the debugging info into the stripped executable.
2082@end enumerate
2083
2084Note---the choice of @code{.dbg} as an extension for the debug info
2085file is arbitrary. Also the @code{--only-keep-debug} step is
2086optional. You could instead do this:
2087
2088@enumerate
2089@item Link the executable as normal.
2090@item Copy @code{foo} to @code{foo.full}
2091@item Run @code{objcopy --strip-debug foo}
2092@item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2093@end enumerate
2094
2095i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2096full executable. It does not have to be a file created by the
2097@option{--only-keep-debug} switch.
2098
2099Note---this switch is only intended for use on fully linked files. It
2100does not make sense to use it on object files where the debugging
2101information may be incomplete. Besides the gnu_debuglink feature
2102currently only supports the presence of one filename containing
2103debugging information, not multiple filenames on a one-per-object-file
2104basis.
2105
2106@item --strip-dwo
2107Remove the contents of all DWARF .dwo sections, leaving the
2108remaining debugging sections and all symbols intact.
2109This option is intended for use by the compiler as part of
2110the @option{-gsplit-dwarf} option, which splits debug information
2111between the .o file and a separate .dwo file. The compiler
2112generates all debug information in the same file, then uses
2113the @option{--extract-dwo} option to copy the .dwo sections to
2114the .dwo file, then the @option{--strip-dwo} option to remove
2115those sections from the original .o file.
2116
2117@item --extract-dwo
2118Extract the contents of all DWARF .dwo sections. See the
2119@option{--strip-dwo} option for more information.
2120
2121@item --file-alignment @var{num}
2122Specify the file alignment. Sections in the file will always begin at
2123file offsets which are multiples of this number. This defaults to
2124512.
2125[This option is specific to PE targets.]
2126
2127@item --heap @var{reserve}
2128@itemx --heap @var{reserve},@var{commit}
2129Specify the number of bytes of memory to reserve (and optionally commit)
2130to be used as heap for this program.
2131[This option is specific to PE targets.]
2132
2133@item --image-base @var{value}
2134Use @var{value} as the base address of your program or dll. This is
2135the lowest memory location that will be used when your program or dll
2136is loaded. To reduce the need to relocate and improve performance of
2137your dlls, each should have a unique base address and not overlap any
2138other dlls. The default is 0x400000 for executables, and 0x10000000
2139for dlls.
2140[This option is specific to PE targets.]
2141
2142@item --section-alignment @var{num}
2143[This option is specific to PE targets.]
2144
2145Sets the section alignment field in the PE header - if one is present
2146in the binary. Sections in memory will always begin at addresses
2147which are a multiple of this number. Defaults to 0x1000.
2148
2149Note - if a section's LMA or VMA addresses are no longer aligned, and
2150those addresses have not been set via the @option{--set-section-lma} or
2151@option{--set-section-vma} options, and the file has been fully
2152relocated then a warning message will be issued. It will then be up
2153to the user to decide if the LMA and VMA need updating.
2154
2155@item --stack @var{reserve}
2156@itemx --stack @var{reserve},@var{commit}
2157Specify the number of bytes of memory to reserve (and optionally commit)
2158to be used as stack for this program.
2159[This option is specific to PE targets.]
2160
2161@item --subsystem @var{which}
2162@itemx --subsystem @var{which}:@var{major}
2163@itemx --subsystem @var{which}:@var{major}.@var{minor}
2164Specifies the subsystem under which your program will execute. The
2165legal values for @var{which} are @code{native}, @code{windows},
2166@code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2167@code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2168the subsystem version also. Numeric values are also accepted for
2169@var{which}.
2170[This option is specific to PE targets.]
2171
2172@item --extract-symbol
2173Keep the file's section flags and symbols but remove all section data.
2174Specifically, the option:
2175
2176@itemize
2177@item removes the contents of all sections;
2178@item sets the size of every section to zero; and
2179@item sets the file's start address to zero.
2180@end itemize
2181
2182This option is used to build a @file{.sym} file for a VxWorks kernel.
2183It can also be a useful way of reducing the size of a @option{--just-symbols}
2184linker input file.
2185
2186@item --compress-debug-sections
2187Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2188ELF ABI. Note - if compression would actually make a section
2189@emph{larger}, then it is not compressed.
2190
2191@item --compress-debug-sections=none
2192@itemx --compress-debug-sections=zlib
2193@itemx --compress-debug-sections=zlib-gnu
2194@itemx --compress-debug-sections=zlib-gabi
2195@itemx --compress-debug-sections=zstd
2196For ELF files, these options control how DWARF debug sections are
2197compressed. @option{--compress-debug-sections=none} is equivalent
2198to @option{--decompress-debug-sections}.
2199@option{--compress-debug-sections=zlib} and
2200@option{--compress-debug-sections=zlib-gabi} are equivalent to
2201@option{--compress-debug-sections}.
2202@option{--compress-debug-sections=zlib-gnu} compresses DWARF debug sections
2203using the obsoleted zlib-gnu format. The debug sections are renamed to begin
2204with @samp{.zdebug}.
2205@option{--compress-debug-sections=zstd} compresses DWARF debug
2206sections using zstd. Note - if compression would actually make a section
2207@emph{larger}, then it is not compressed nor renamed.
2208
2209@item --decompress-debug-sections
2210Decompress DWARF debug sections. For a @samp{.zdebug} section, the original
2211name is restored.
2212
2213@item --elf-stt-common=yes
2214@itemx --elf-stt-common=no
2215For ELF files, these options control whether common symbols should be
2216converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2217@option{--elf-stt-common=yes} converts common symbol type to
2218@code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2219type to @code{STT_OBJECT}.
2220
2221@item --merge-notes
2222@itemx --no-merge-notes
2223For ELF files, attempt (or do not attempt) to reduce the size of any
2224SHT_NOTE type sections by removing duplicate notes.
2225
2226@item -V
2227@itemx --version
2228Show the version number of @command{objcopy}.
2229
2230@item --verilog-data-width=@var{bytes}
2231For Verilog output, this options controls the number of bytes
2232converted for each output data element. The input target controls the
2233endianness of the conversion.
2234
2235@item -v
2236@itemx --verbose
2237Verbose output: list all object files modified. In the case of
2238archives, @samp{objcopy -V} lists all members of the archive.
2239
2240@item --help
2241Show a summary of the options to @command{objcopy}.
2242
2243@item --info
2244Display a list showing all architectures and object formats available.
2245@end table
2246
2247@c man end
2248
2249@ignore
2250@c man begin SEEALSO objcopy
2251ld(1), objdump(1), and the Info entries for @file{binutils}.
2252@c man end
2253@end ignore
2254
2255@node objdump
2256@chapter objdump
2257
2258@cindex object file information
2259@kindex objdump
2260
2261@c man title objdump display information from object files
2262
2263@smallexample
2264@c man begin SYNOPSIS objdump
2265objdump [@option{-a}|@option{--archive-headers}]
2266 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2267 [@option{-C}|@option{--demangle}[=@var{style}] ]
2268 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2269 [@option{-D}|@option{--disassemble-all}]
2270 [@option{-z}|@option{--disassemble-zeroes}]
2271 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2272 [@option{-f}|@option{--file-headers}]
2273 [@option{-F}|@option{--file-offsets}]
2274 [@option{--file-start-context}]
2275 [@option{-g}|@option{--debugging}]
2276 [@option{-e}|@option{--debugging-tags}]
2277 [@option{-h}|@option{--section-headers}|@option{--headers}]
2278 [@option{-i}|@option{--info}]
2279 [@option{-j} @var{section}|@option{--section=}@var{section}]
2280 [@option{-l}|@option{--line-numbers}]
2281 [@option{-S}|@option{--source}]
2282 [@option{--source-comment}[=@var{text}]]
2283 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2284 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2285 [@option{-p}|@option{--private-headers}]
2286 [@option{-P} @var{options}|@option{--private=}@var{options}]
2287 [@option{-r}|@option{--reloc}]
2288 [@option{-R}|@option{--dynamic-reloc}]
2289 [@option{-s}|@option{--full-contents}]
2290 [@option{-Z}|@option{--decompress}]
2291 [@option{-W[lLiaprmfFsoORtUuTgAck]}|
2292 @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]]
2293 [@option{-WK}|@option{--dwarf=follow-links}]
2294 [@option{-WN}|@option{--dwarf=no-follow-links}]
2295 [@option{-wD}|@option{--dwarf=use-debuginfod}]
2296 [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
2297 [@option{-L}|@option{--process-links}]
2298 [@option{--ctf=}@var{section}]
2299 [@option{--sframe=}@var{section}]
2300 [@option{-G}|@option{--stabs}]
2301 [@option{-t}|@option{--syms}]
2302 [@option{-T}|@option{--dynamic-syms}]
2303 [@option{-x}|@option{--all-headers}]
2304 [@option{-w}|@option{--wide}]
2305 [@option{--start-address=}@var{address}]
2306 [@option{--stop-address=}@var{address}]
2307 [@option{--no-addresses}]
2308 [@option{--prefix-addresses}]
2309 [@option{--[no-]show-raw-insn}]
2310 [@option{--adjust-vma=}@var{offset}]
2311 [@option{--show-all-symbols}]
2312 [@option{--dwarf-depth=@var{n}}]
2313 [@option{--dwarf-start=@var{n}}]
2314 [@option{--ctf-parent=}@var{section}]
2315 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2316 [@option{--special-syms}]
2317 [@option{--prefix=}@var{prefix}]
2318 [@option{--prefix-strip=}@var{level}]
2319 [@option{--insn-width=}@var{width}]
2320 [@option{--visualize-jumps[=color|=extended-color|=off]}
2321 [@option{--disassembler-color=[off|terminal|on|extended]}
2322 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
2323 [@option{-V}|@option{--version}]
2324 [@option{-H}|@option{--help}]
2325 @var{objfile}@dots{}
2326@c man end
2327@end smallexample
2328
2329@c man begin DESCRIPTION objdump
2330
2331@command{objdump} displays information about one or more object files.
2332The options control what particular information to display. This
2333information is mostly useful to programmers who are working on the
2334compilation tools, as opposed to programmers who just want their
2335program to compile and work.
2336
2337@var{objfile}@dots{} are the object files to be examined. When you
2338specify archives, @command{objdump} shows information on each of the member
2339object files.
2340
2341@c man end
2342
2343@c man begin OPTIONS objdump
2344
2345The long and short forms of options, shown here as alternatives, are
2346equivalent. At least one option from the list
2347@option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2348
2349@table @env
2350@item -a
2351@itemx --archive-header
2352@cindex archive headers
2353If any of the @var{objfile} files are archives, display the archive
2354header information (in a format similar to @samp{ls -l}). Besides the
2355information you could list with @samp{ar tv}, @samp{objdump -a} shows
2356the object file format of each archive member.
2357
2358@item --adjust-vma=@var{offset}
2359@cindex section addresses in objdump
2360@cindex VMA in objdump
2361When dumping information, first add @var{offset} to all the section
2362addresses. This is useful if the section addresses do not correspond to
2363the symbol table, which can happen when putting sections at particular
2364addresses when using a format which can not represent section addresses,
2365such as a.out.
2366
2367@item -b @var{bfdname}
2368@itemx --target=@var{bfdname}
2369@cindex object code format
2370Specify that the object-code format for the object files is
2371@var{bfdname}. This option may not be necessary; @var{objdump} can
2372automatically recognize many formats.
2373
2374For example,
2375@example
2376objdump -b oasys -m vax -h fu.o
2377@end example
2378@noindent
2379displays summary information from the section headers (@option{-h}) of
2380@file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2381file in the format produced by Oasys compilers. You can list the
2382formats available with the @option{-i} option.
2383@xref{Target Selection}, for more information.
2384
2385@item -C
2386@itemx --demangle[=@var{style}]
2387@cindex demangling in objdump
2388Decode (@dfn{demangle}) low-level symbol names into user-level names.
2389Besides removing any initial underscore prepended by the system, this
2390makes C++ function names readable. Different compilers have different
2391mangling styles. The optional demangling style argument can be used to
2392choose an appropriate demangling style for your compiler. @xref{c++filt},
2393for more information on demangling.
2394
2395@item --recurse-limit
2396@itemx --no-recurse-limit
2397@itemx --recursion-limit
2398@itemx --no-recursion-limit
2399Enables or disables a limit on the amount of recursion performed
2400whilst demangling strings. Since the name mangling formats allow for
2401an infinite level of recursion it is possible to create strings whose
2402decoding will exhaust the amount of stack space available on the host
2403machine, triggering a memory fault. The limit tries to prevent this
2404from happening by restricting recursion to 2048 levels of nesting.
2405
2406The default is for this limit to be enabled, but disabling it may be
2407necessary in order to demangle truly complicated names. Note however
2408that if the recursion limit is disabled then stack exhaustion is
2409possible and any bug reports about such an event will be rejected.
2410
2411@item -g
2412@itemx --debugging
2413Display debugging information. This attempts to parse STABS
2414debugging format information stored in the file and print it out using
2415a C like syntax. If no STABS debugging was found this option
2416falls back on the @option{-W} option to print any DWARF information in
2417the file.
2418
2419@item -e
2420@itemx --debugging-tags
2421Like @option{-g}, but the information is generated in a format compatible
2422with ctags tool.
2423
2424@item -d
2425@itemx --disassemble
2426@itemx --disassemble=@var{symbol}
2427@cindex disassembling object code
2428@cindex machine instructions
2429Display the assembler mnemonics for the machine instructions from the
2430input file. This option only disassembles those sections which are
2431expected to contain instructions. If the optional @var{symbol}
2432argument is given (perhaps multiple times), then display the assembler
2433mnemonics starting at (all the) @var{symbol}. If @var{symbol} is a
2434function name then disassembly will stop at the end of the function,
2435otherwise it will stop when the next symbol is encountered. If there
2436are no matches for any @var{symbol} then nothing will be displayed.
2437
2438Note if the @option{--dwarf=follow-links} option is enabled
2439then any symbol tables in linked debug info files will be read in and
2440used when disassembling.
2441
2442@item -D
2443@itemx --disassemble-all
2444Like @option{-d}, but disassemble the contents of all non-empty
2445non-bss sections, not just those expected to contain instructions.
2446@option{-j} may be used to select specific sections.
2447
2448This option also has a subtle effect on the disassembly of
2449instructions in code sections. When option @option{-d} is in effect
2450objdump will assume that any symbols present in a code section occur
2451on the boundary between instructions and it will refuse to disassemble
2452across such a boundary. When option @option{-D} is in effect however
2453this assumption is supressed. This means that it is possible for the
2454output of @option{-d} and @option{-D} to differ if, for example, data
2455is stored in code sections.
2456
2457If the target is an ARM architecture this switch also has the effect
2458of forcing the disassembler to decode pieces of data found in code
2459sections as if they were instructions.
2460
2461Note if the @option{--dwarf=follow-links} option is enabled
2462then any symbol tables in linked debug info files will be read in and
2463used when disassembling.
2464
2465@item --no-addresses
2466When disassembling, don't print addresses on each line or for symbols
2467and relocation offsets. In combination with @option{--no-show-raw-insn}
2468this may be useful for comparing compiler output.
2469
2470@item --prefix-addresses
2471When disassembling, print the complete address on each line. This is
2472the older disassembly format.
2473
2474@item -EB
2475@itemx -EL
2476@itemx --endian=@{big|little@}
2477@cindex endianness
2478@cindex disassembly endianness
2479Specify the endianness of the object files. This only affects
2480disassembly. This can be useful when disassembling a file format which
2481does not describe endianness information, such as S-records.
2482
2483@item -f
2484@itemx --file-headers
2485@cindex object file header
2486Display summary information from the overall header of
2487each of the @var{objfile} files.
2488
2489@item -F
2490@itemx --file-offsets
2491@cindex object file offsets
2492When disassembling sections, whenever a symbol is displayed, also
2493display the file offset of the region of data that is about to be
2494dumped. If zeroes are being skipped, then when disassembly resumes,
2495tell the user how many zeroes were skipped and the file offset of the
2496location from where the disassembly resumes. When dumping sections,
2497display the file offset of the location from where the dump starts.
2498
2499@item --file-start-context
2500@cindex source code context
2501Specify that when displaying interlisted source code/disassembly
2502(assumes @option{-S}) from a file that has not yet been displayed, extend the
2503context to the start of the file.
2504
2505@item -h
2506@itemx --section-headers
2507@itemx --headers
2508@cindex section headers
2509Display summary information from the section headers of the
2510object file.
2511
2512File segments may be relocated to nonstandard addresses, for example by
2513using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2514@command{ld}. However, some object file formats, such as a.out, do not
2515store the starting address of the file segments. In those situations,
2516although @command{ld} relocates the sections correctly, using @samp{objdump
2517-h} to list the file section headers cannot show the correct addresses.
2518Instead, it shows the usual addresses, which are implicit for the
2519target.
2520
2521Note, in some cases it is possible for a section to have both the
2522READONLY and the NOREAD attributes set. In such cases the NOREAD
2523attribute takes precedence, but @command{objdump} will report both
2524since the exact setting of the flag bits might be important.
2525
2526@item -H
2527@itemx --help
2528Print a summary of the options to @command{objdump} and exit.
2529
2530@item -i
2531@itemx --info
2532@cindex architectures available
2533@cindex object formats available
2534Display a list showing all architectures and object formats available
2535for specification with @option{-b} or @option{-m}.
2536
2537@item -j @var{name}
2538@itemx --section=@var{name}
2539@cindex section information
2540Display information for section @var{name}. This option may be
2541specified multiple times.
2542
2543@item -L
2544@itemx --process-links
2545Display the contents of non-debug sections found in separate debuginfo
2546files that are linked to the main file. This option automatically
2547implies the @option{-WK} option, and only sections requested by other
2548command line options will be displayed.
2549
2550@item -l
2551@itemx --line-numbers
2552@cindex source filenames for object files
2553Label the display (using debugging information) with the filename and
2554source line numbers corresponding to the object code or relocs shown.
2555Only useful with @option{-d}, @option{-D}, or @option{-r}.
2556
2557@item -m @var{machine}
2558@itemx --architecture=@var{machine}
2559@cindex architecture
2560@cindex disassembly architecture
2561Specify the architecture to use when disassembling object files. This
2562can be useful when disassembling object files which do not describe
2563architecture information, such as S-records. You can list the available
2564architectures with the @option{-i} option.
2565
2566For most architectures it is possible to supply an architecture
2567name and a machine name, separated by a colon. For example
2568@samp{foo:bar} would refer to the @samp{bar} machine type in the
2569@samp{foo} architecture. This can be helpful if objdump has been
2570configured to support multiple architectures.
2571
2572If the target is an ARM architecture then this switch has an
2573additional effect. It restricts the disassembly to only those
2574instructions supported by the architecture specified by @var{machine}.
2575If it is necessary to use this switch because the input file does not
2576contain any architecture information, but it is also desired to
2577disassemble all the instructions use @option{-marm}.
2578
2579@item -M @var{options}
2580@itemx --disassembler-options=@var{options}
2581Pass target specific information to the disassembler. Only supported on
2582some targets. If it is necessary to specify more than one
2583disassembler option then multiple @option{-M} options can be used or
2584can be placed together into a comma separated list.
2585
2586For ARC, @option{dsp} controls the printing of DSP instructions,
2587@option{spfp} selects the printing of FPX single precision FP
2588instructions, @option{dpfp} selects the printing of FPX double
2589precision FP instructions, @option{quarkse_em} selects the printing of
2590special QuarkSE-EM instructions, @option{fpuda} selects the printing
2591of double precision assist instructions, @option{fpus} selects the
2592printing of FPU single precision FP instructions, while @option{fpud}
2593selects the printing of FPU double precision FP instructions.
2594Additionally, one can choose to have all the immediates printed in
2595hexadecimal using @option{hex}. By default, the short immediates are
2596printed using the decimal representation, while the long immediate
2597values are printed as hexadecimal.
2598
2599@option{cpu=...} allows one to enforce a particular ISA when disassembling
2600instructions, overriding the @option{-m} value or whatever is in the ELF file.
2601This might be useful to select ARC EM or HS ISA, because architecture is same
2602for those and disassembler relies on private ELF header data to decide if code
2603is for EM or HS. This option might be specified multiple times - only the
2604latest value will be used. Valid values are same as for the assembler
2605@option{-mcpu=...} option.
2606
2607If the target is an ARM architecture then this switch can be used to
2608select which register name set is used during disassembler. Specifying
2609@option{-M reg-names-std} (the default) will select the register names as
2610used in ARM's instruction set documentation, but with register 13 called
2611'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2612@option{-M reg-names-apcs} will select the name set used by the ARM
2613Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2614just use @samp{r} followed by the register number.
2615
2616There are also two variants on the APCS register naming scheme enabled
2617by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2618use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2619with the normal register names or the special register names).
2620
2621This option can also be used for ARM architectures to force the
2622disassembler to interpret all instructions as Thumb instructions by
2623using the switch @option{--disassembler-options=force-thumb}. This can be
2624useful when attempting to disassemble thumb code produced by other
2625compilers.
2626
2627For AArch64 targets this switch can be used to set whether instructions are
2628disassembled as the most general instruction using the @option{-M no-aliases}
2629option or whether instruction notes should be generated as comments in the
2630disasssembly using @option{-M notes}.
2631
2632For the x86, some of the options duplicate functions of the @option{-m}
2633switch, but allow finer grained control.
2634@table @code
2635@item x86-64
2636@itemx i386
2637@itemx i8086
2638Select disassembly for the given architecture.
2639
2640@item intel
2641@itemx att
2642Select between intel syntax mode and AT&T syntax mode.
2643
2644@item amd64
2645@itemx intel64
2646Select between AMD64 ISA and Intel64 ISA.
2647
2648@item intel-mnemonic
2649@itemx att-mnemonic
2650Select between intel mnemonic mode and AT&T mnemonic mode.
2651Note: @code{intel-mnemonic} implies @code{intel} and
2652@code{att-mnemonic} implies @code{att}.
2653
2654@item addr64
2655@itemx addr32
2656@itemx addr16
2657@itemx data32
2658@itemx data16
2659Specify the default address size and operand size. These five options
2660will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2661appear later in the option string.
2662
2663@item suffix
2664When in AT&T mode and also for a limited set of instructions when in Intel
2665mode, instructs the disassembler to print a mnemonic suffix even when the
2666suffix could be inferred by the operands or, for certain instructions, the
2667execution mode's defaults.
2668@end table
2669
2670For PowerPC, the @option{-M} argument @option{raw} selects
2671disasssembly of hardware insns rather than aliases. For example, you
2672will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2673rather than @code{li}. All of the @option{-m} arguments for
2674@command{gas} that select a CPU are supported. These are:
2675@option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2676@option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2677@option{7410}, @option{7450}, @option{7455}, @option{750cl},
2678@option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2679@option{booke32}, @option{cell}, @option{com}, @option{e200z2}, @option{e200z4},
2680@option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2681@option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2682@option{power4}, @option{power5}, @option{power6}, @option{power7},
2683@option{power8}, @option{power9}, @option{power10}, @option{power11},
2684@option{ppc}, @option{ppc32}, @option{ppc64}, @option{ppc64bridge},
2685@option{ppcps}, @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5},
2686@option{pwr5x}, @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2687@option{pwr10}, @option{pwr11}, @option{pwrx}, @option{titan}, @option{vle},
2688and @option{future}.
2689@option{32} and @option{64} modify the default or a prior CPU
2690selection, disabling and enabling 64-bit insns respectively. In
2691addition, @option{altivec}, @option{any}, @option{lsp}, @option{htm},
2692@option{vsx}, @option{spe} and @option{spe2} add capabilities to a
2693previous @emph{or later} CPU selection.
2694@option{any} will disassemble any opcode known to
2695binutils, but in cases where an opcode has two different meanings or
2696different arguments, you may not see the disassembly you expect.
2697If you disassemble without giving a CPU selection, a default will be
2698chosen from information gleaned by BFD from the object files headers,
2699but the result again may not be as you expect.
2700
2701For RISC-V, the following options are supported:
2702
2703@table @code
2704@item max
2705Disassemble without checking architecture string. This is a best effort mode, so
2706for overlapping ISA extensions the first match (possibly incorrect in a given
2707context) will be used to decode the instruction. It's useful, if the ELF file
2708doesn't expose ISA string, preventing automatic ISA subset deduction, and the
2709default fallback ISA string (@code{rv64gc}) doesn't cover all instructions in
2710the binary.
2711
2712@item numeric
2713Print numeric register names, rather than ABI names (e.g., print @code{x2}
2714instead of @code{sp}).
2715
2716@item no-aliases
2717Disassemble only into canonical instructions. For example, compressed
2718instructions will be represented as such (@code{addi sp,sp,-128} will be
2719@code{c.addi16sp sp,-128}).
2720
2721@item priv-spec=@var{SPEC}
2722Print the CSR according to the chosen privilege spec version (e.g.,
2723@code{1.10}, @code{1.11}, @code{1.12}, @code{1.13}).
2724@end table
2725
2726For MIPS, this option controls the printing of instruction mnemonic
2727names and register names in disassembled instructions. Multiple
2728selections from the following may be specified as a comma separated
2729string, and invalid options are ignored:
2730
2731@table @code
2732@item no-aliases
2733Print the 'raw' instruction mnemonic instead of some pseudo
2734instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2735'sll' instead of 'nop', etc.
2736
2737@item msa
2738Disassemble MSA instructions.
2739
2740@item virt
2741Disassemble the virtualization ASE instructions.
2742
2743@item xpa
2744Disassemble the eXtended Physical Address (XPA) ASE instructions.
2745
2746@item gpr-names=@var{ABI}
2747Print GPR (general-purpose register) names as appropriate
2748for the specified ABI. By default, GPR names are selected according to
2749the ABI of the binary being disassembled.
2750
2751@item fpr-names=@var{ABI}
2752Print FPR (floating-point register) names as
2753appropriate for the specified ABI. By default, FPR numbers are printed
2754rather than names.
2755
2756@item cp0-names=@var{ARCH}
2757Print CP0 (system control coprocessor; coprocessor 0) register names
2758as appropriate for the CPU or architecture specified by
2759@var{ARCH}. By default, CP0 register names are selected according to
2760the architecture and CPU of the binary being disassembled.
2761
2762@item hwr-names=@var{ARCH}
2763Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2764as appropriate for the CPU or architecture specified by
2765@var{ARCH}. By default, HWR names are selected according to
2766the architecture and CPU of the binary being disassembled.
2767
2768@item reg-names=@var{ABI}
2769Print GPR and FPR names as appropriate for the selected ABI.
2770
2771@item reg-names=@var{ARCH}
2772Print CPU-specific register names (CP0 register and HWR names)
2773as appropriate for the selected CPU or architecture.
2774@end table
2775
2776For any of the options listed above, @var{ABI} or
2777@var{ARCH} may be specified as @samp{numeric} to have numbers printed
2778rather than names, for the selected types of registers.
2779You can list the available values of @var{ABI} and @var{ARCH} using
2780the @option{--help} option.
2781
2782For VAX, you can specify function entry addresses with @option{-M
2783entry:0xf00ba}. You can use this multiple times to properly
2784disassemble VAX binary files that don't contain symbol tables (like
2785ROM dumps). In these cases, the function entry mask would otherwise
2786be decoded as VAX instructions, which would probably lead the rest
2787of the function being wrongly disassembled.
2788
2789@item -p
2790@itemx --private-headers
2791Print information that is specific to the object file format. The exact
2792information printed depends upon the object file format. For some
2793object file formats, no additional information is printed.
2794
2795@item -P @var{options}
2796@itemx --private=@var{options}
2797Print information that is specific to the object file format. The
2798argument @var{options} is a comma separated list that depends on the
2799format (the lists of options is displayed with the help).
2800
2801For XCOFF, the available options are:
2802@table @code
2803@item header
2804@item aout
2805@item sections
2806@item syms
2807@item relocs
2808@item lineno,
2809@item loader
2810@item except
2811@item typchk
2812@item traceback
2813@item toc
2814@item ldinfo
2815@end table
2816
2817For PE, the available options are:
2818@table @code
2819@item header
2820@item sections
2821@end table
2822
2823Not all object formats support this option. In particular the ELF
2824format does not use it.
2825
2826@item -r
2827@itemx --reloc
2828@cindex relocation entries, in object file
2829Print the relocation entries of the file. If used with @option{-d} or
2830@option{-D}, the relocations are printed interspersed with the
2831disassembly.
2832
2833@item -R
2834@itemx --dynamic-reloc
2835@cindex dynamic relocation entries, in object file
2836Print the dynamic relocation entries of the file. This is only
2837meaningful for dynamic objects, such as certain types of shared
2838libraries. As for @option{-r}, if used with @option{-d} or
2839@option{-D}, the relocations are printed interspersed with the
2840disassembly.
2841
2842Note: @command{objdump} does not support displaying RELR type
2843relocations. These can be displayed by the @command{readelf} program.
2844
2845@item -s
2846@itemx --full-contents
2847@cindex sections, full contents
2848@cindex object file sections
2849Display the full contents of sections, often used in combination with
2850@option{-j} to request specific sections. By default all non-empty
2851non-bss sections are displayed. By default any compressed section
2852will be displayed in its compressed form. In order to see the
2853contents in a decompressed form add the @option{-Z} option to the
2854command line.
2855
2856@item -S
2857@itemx --source
2858@cindex source disassembly
2859@cindex disassembly, with source
2860Display source code intermixed with disassembly, if possible. Implies
2861@option{-d}.
2862
2863@item --show-all-symbols
2864When disassembling, show all the symbols that match a given address,
2865not just the first one.
2866
2867@item --source-comment[=@var{txt}]
2868@cindex source disassembly
2869@cindex disassembly, with source
2870Like the @option{-S} option, but all source code lines are displayed
2871with a prefix of @var{txt}. Typically @var{txt} will be a comment
2872string which can be used to distinguish the assembler code from the
2873source code. If @var{txt} is not provided then a default string of
2874@var{``# ``} (hash followed by a space), will be used.
2875
2876@item --prefix=@var{prefix}
2877@cindex Add prefix to absolute paths
2878Specify @var{prefix} to add to the absolute paths when used with
2879@option{-S}.
2880
2881@item --prefix-strip=@var{level}
2882@cindex Strip absolute paths
2883Indicate how many initial directory names to strip off the hardwired
2884absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2885
2886@item --show-raw-insn
2887When disassembling instructions, print the instruction in hex as well as
2888in symbolic form. This is the default except when
2889@option{--prefix-addresses} is used.
2890
2891@item --no-show-raw-insn
2892When disassembling instructions, do not print the instruction bytes.
2893This is the default when @option{--prefix-addresses} is used.
2894
2895@item --insn-width=@var{width}
2896@cindex Instruction width
2897Display @var{width} bytes on a single line when disassembling
2898instructions.
2899
2900@item --visualize-jumps[=color|=extended-color|=off]
2901Visualize jumps that stay inside a function by drawing ASCII art between
2902the start and target addresses. The optional @option{=color} argument
2903adds color to the output using simple terminal colors. Alternatively
2904the @option{=extended-color} argument will add color using 8bit
2905colors, but these might not work on all terminals.
2906
2907If it is necessary to disable the @option{visualize-jumps} option
2908after it has previously been enabled then use
2909@option{visualize-jumps=off}.
2910
2911@item --disassembler-color=off
2912@itemx --disassembler-color=terminal
2913@itemx --disassembler-color=on|color|colour
2914@itemx --disassembler-color=extended|extended-color|extended-colour
2915Enables or disables the use of colored syntax highlighting in
2916disassembly output. The default behaviour is determined via a
2917configure time option. Note, not all architectures support colored
2918syntax highlighting, and depending upon the terminal used, colored
2919output may not actually be legible.
2920
2921The @option{on} argument adds colors using simple terminal colors.
2922
2923The @option{terminal} argument does the same, but only if the output
2924device is a terminal.
2925
2926The @option{extended-color} argument is similar to the @option{on}
2927argument, but it uses 8-bit colors. These may not work on all
2928terminals.
2929
2930The @option{off} argument disables colored disassembly.
2931
2932@item -W[lLiaprmfFsoORtUuTgAckK]
2933@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]
2934@include debug.options.texi
2935
2936@item --dwarf-check
2937Enable additional checks for consistency of Dwarf information.
2938
2939@include ctf.options.texi
2940
2941@include sframe.options.texi
2942
2943@item -G
2944@itemx --stabs
2945@cindex stab
2946@cindex .stab
2947@cindex debug symbols
2948@cindex ELF object file format
2949Display the full contents of any sections requested. Display the
2950contents of the .stab and .stab.index and .stab.excl sections from an
2951ELF file. This is only useful on systems (such as Solaris 2.0) in which
2952@code{.stab} debugging symbol-table entries are carried in an ELF
2953section. In most other file formats, debugging symbol-table entries are
2954interleaved with linkage symbols, and are visible in the @option{--syms}
2955output.
2956
2957@item --start-address=@var{address}
2958@cindex start-address
2959Start displaying data at the specified address. This affects the output
2960of the @option{-d}, @option{-r} and @option{-s} options.
2961
2962@item --stop-address=@var{address}
2963@cindex stop-address
2964Stop displaying data at the specified address. This affects the output
2965of the @option{-d}, @option{-r} and @option{-s} options.
2966
2967@item -t
2968@itemx --syms
2969@cindex symbol table entries, printing
2970Print the symbol table entries of the file.
2971This is similar to the information provided by the @samp{nm} program,
2972although the display format is different. The format of the output
2973depends upon the format of the file being dumped, but there are two main
2974types. One looks like this:
2975
2976@smallexample
2977[ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2978[ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2979@end smallexample
2980
2981where the number inside the square brackets is the number of the entry
2982in the symbol table, the @var{sec} number is the section number, the
2983@var{fl} value are the symbol's flag bits, the @var{ty} number is the
2984symbol's type, the @var{scl} number is the symbol's storage class and
2985the @var{nx} value is the number of auxiliary entries associated with
2986the symbol. The last two fields are the symbol's value and its name.
2987
2988The other common output format, usually seen with ELF based files,
2989looks like this:
2990
2991@smallexample
299200000000 l d .bss 00000000 .bss
299300000000 g .text 00000000 fred
2994@end smallexample
2995
2996Here the first number is the symbol's value (sometimes referred to as
2997its address). The next field is actually a set of characters and
2998spaces indicating the flag bits that are set on the symbol. These
2999characters are described below. Next is the section with which the
3000symbol is associated or @emph{*ABS*} if the section is absolute (ie
3001not connected with any section), or @emph{*UND*} if the section is
3002referenced in the file being dumped, but not defined there.
3003
3004After the section name comes another field, a number, which for common
3005symbols is the alignment and for other symbol is the size. Finally
3006the symbol's name is displayed.
3007
3008The flag characters are divided into 7 groups as follows:
3009@table @code
3010@item l
3011@itemx g
3012@itemx u
3013@itemx !
3014The symbol is a local (l), global (g), unique global (u), neither
3015global nor local (a space) or both global and local (!). A
3016symbol can be neither local or global for a variety of reasons, e.g.,
3017because it is used for debugging, but it is probably an indication of
3018a bug if it is ever both local and global. Unique global symbols are
3019a GNU extension to the standard set of ELF symbol bindings. For such
3020a symbol the dynamic linker will make sure that in the entire process
3021there is just one symbol with this name and type in use.
3022
3023@item w
3024The symbol is weak (w) or strong (a space).
3025
3026@item C
3027The symbol denotes a constructor (C) or an ordinary symbol (a space).
3028
3029@item W
3030The symbol is a warning (W) or a normal symbol (a space). A warning
3031symbol's name is a message to be displayed if the symbol following the
3032warning symbol is ever referenced.
3033
3034@item I
3035@item i
3036The symbol is an indirect reference to another symbol (I), a function
3037to be evaluated during reloc processing (i) or a normal symbol (a
3038space).
3039
3040@item d
3041@itemx D
3042The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
3043normal symbol (a space).
3044
3045@item F
3046@item f
3047@item O
3048The symbol is the name of a function (F) or a file (f) or an object
3049(O) or just a normal symbol (a space).
3050@end table
3051
3052@item -T
3053@itemx --dynamic-syms
3054@cindex dynamic symbol table entries, printing
3055Print the dynamic symbol table entries of the file. This is only
3056meaningful for dynamic objects, such as certain types of shared
3057libraries. This is similar to the information provided by the @samp{nm}
3058program when given the @option{-D} (@option{--dynamic}) option.
3059
3060The output format is similar to that produced by the @option{--syms}
3061option, except that an extra field is inserted before the symbol's
3062name, giving the version information associated with the symbol.
3063If the version is the default version to be used when resolving
3064unversioned references to the symbol then it's displayed as is,
3065otherwise it's put into parentheses.
3066
3067@item --special-syms
3068When displaying symbols include those which the target considers to be
3069special in some way and which would not normally be of interest to the
3070user.
3071
3072@item -U @var{[d|i|l|e|x|h]}
3073@itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3074Controls the display of UTF-8 encoded multibyte characters in strings.
3075The default (@option{--unicode=default}) is to give them no special
3076treatment. The @option{--unicode=locale} option displays the sequence
3077in the current locale, which may or may not support them. The options
3078@option{--unicode=hex} and @option{--unicode=invalid} display them as
3079hex byte sequences enclosed by either angle brackets or curly braces.
3080
3081The @option{--unicode=escape} option displays them as escape sequences
3082(@var{\uxxxx}) and the @option{--unicode=highlight} option displays
3083them as escape sequences highlighted in red (if supported by the
3084output device). The colouring is intended to draw attention to the
3085presence of unicode sequences where they might not be expected.
3086
3087@item -V
3088@itemx --version
3089Print the version number of @command{objdump} and exit.
3090
3091@item -x
3092@itemx --all-headers
3093@cindex all header information, object file
3094@cindex header information, all
3095Display all available header information, including the symbol table and
3096relocation entries. Using @option{-x} is equivalent to specifying all of
3097@option{-a -f -h -p -r -t}.
3098
3099@item -w
3100@itemx --wide
3101@cindex wide output, printing
3102Format some lines for output devices that have more than 80 columns.
3103Also do not truncate symbol names when they are displayed.
3104
3105@item -z
3106@itemx --disassemble-zeroes
3107Normally the disassembly output will skip blocks of zeroes. This
3108option directs the disassembler to disassemble those blocks, just like
3109any other data.
3110
3111@item -Z
3112@itemx --decompress
3113@cindex sections, full contents
3114@cindex object file sections
3115@cindex compressed section contents
3116The @option{-Z} option is meant to be used in conunction with the
3117@option{-s} option. It instructs @command{objdump} to decompress any
3118compressed sections before displaying their contents.
3119@end table
3120
3121@c man end
3122
3123@ignore
3124@c man begin SEEALSO objdump
3125nm(1), readelf(1), and the Info entries for @file{binutils}.
3126@c man end
3127@end ignore
3128
3129@node ranlib
3130@chapter ranlib
3131
3132@kindex ranlib
3133@cindex archive contents
3134@cindex symbol index
3135
3136@c man title ranlib generate an index to an archive
3137
3138@smallexample
3139@c man begin SYNOPSIS ranlib
3140ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
3141@c man end
3142@end smallexample
3143
3144@c man begin DESCRIPTION ranlib
3145
3146@command{ranlib} generates an index to the contents of an archive and
3147stores it in the archive. The index lists each symbol defined by a
3148member of an archive that is a relocatable object file.
3149
3150You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
3151
3152An archive with such an index speeds up linking to the library and
3153allows routines in the library to call each other without regard to
3154their placement in the archive.
3155
3156The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
3157@command{ranlib} is completely equivalent to executing @samp{ar -s}.
3158@xref{ar}.
3159
3160@c man end
3161
3162@c man begin OPTIONS ranlib
3163
3164@table @env
3165@item -h
3166@itemx -H
3167@itemx --help
3168Show usage information for @command{ranlib}.
3169
3170@item -v
3171@itemx -V
3172@itemx --version
3173Show the version number of @command{ranlib}.
3174
3175@item -D
3176@cindex deterministic archives
3177@kindex --enable-deterministic-archives
3178Operate in @emph{deterministic} mode. The symbol map archive member's
3179header will show zero for the UID, GID, and timestamp. When this
3180option is used, multiple runs will produce identical output files.
3181
3182If @file{binutils} was configured with
3183@option{--enable-deterministic-archives}, then this mode is on by
3184default. It can be disabled with the @samp{-U} option, described
3185below.
3186
3187@item -t
3188Update the timestamp of the symbol map of an archive.
3189
3190@item -U
3191@cindex deterministic archives
3192@kindex --enable-deterministic-archives
3193Do @emph{not} operate in @emph{deterministic} mode. This is the
3194inverse of the @samp{-D} option, above: the archive index will get
3195actual UID, GID, timestamp, and file mode values.
3196
3197If @file{binutils} was configured @emph{without}
3198@option{--enable-deterministic-archives}, then this mode is on by
3199default.
3200
3201@end table
3202
3203@c man end
3204
3205@ignore
3206@c man begin SEEALSO ranlib
3207ar(1), nm(1), and the Info entries for @file{binutils}.
3208@c man end
3209@end ignore
3210
3211@node size
3212@chapter size
3213
3214@kindex size
3215@cindex section sizes
3216
3217@c man title size list section sizes and total size of binary files
3218
3219@smallexample
3220@c man begin SYNOPSIS size
3221size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
3222 [@option{--help}]
3223 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
3224 [@option{--common}]
3225 [@option{-t}|@option{--totals}]
3226 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
3227 [@option{-f}]
3228 [@var{objfile}@dots{}]
3229@c man end
3230@end smallexample
3231
3232@c man begin DESCRIPTION size
3233
3234The @sc{gnu} @command{size} utility lists the section sizes and the total
3235size for each of the binary files @var{objfile} on its argument list.
3236By default, one line of output is generated for each file or each
3237module if the file is an archive.
3238
3239@var{objfile}@dots{} are the files to be examined. If none are
3240specified, the file @code{a.out} will be used instead.
3241
3242@c man end
3243
3244@c man begin OPTIONS size
3245
3246The command-line options have the following meanings:
3247
3248@table @env
3249@item -A
3250@itemx -B
3251@itemx -G
3252@itemx --format=@var{compatibility}
3253@cindex @command{size} display format
3254Using one of these options, you can choose whether the output from @sc{gnu}
3255@command{size} resembles output from System V @command{size} (using @option{-A},
3256or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3257@option{--format=berkeley}). The default is the one-line format similar to
3258Berkeley's. Alternatively, you can choose the GNU format output
3259(using @option{-G}, or @option{--format=gnu}), this is similar to
3260Berkeley's output format, but sizes are counted differently.
3261@c Bonus for doc-source readers: you can also say --format=strange (or
3262@c anything else that starts with 's') for sysv, and --format=boring (or
3263@c anything else that starts with 'b') for Berkeley.
3264
3265Here is an example of the Berkeley (default) format of output from
3266@command{size}:
3267@smallexample
3268$ size --format=Berkeley ranlib size
3269 text data bss dec hex filename
3270 294880 81920 11592 388392 5ed28 ranlib
3271 294880 81920 11888 388688 5ee50 size
3272@end smallexample
3273
3274The Berkeley style output counts read only data in the @code{text}
3275column, not in the @code{data} column, the @code{dec} and @code{hex}
3276columns both display the sum of the @code{text}, @code{data}, and
3277@code{bss} columns in decimal and hexadecimal respectively.
3278
3279The GNU format counts read only data in the @code{data} column, not
3280the @code{text} column, and only displays the sum of the @code{text},
3281@code{data}, and @code{bss} columns once, in the @code{total} column.
3282The @option{--radix} option can be used to change the number base for
3283all columns. Here is the same data displayed with GNU conventions:
3284
3285@smallexample
3286$ size --format=GNU ranlib size
3287 text data bss total filename
3288 279880 96920 11592 388392 ranlib
3289 279880 96920 11888 388688 size
3290@end smallexample
3291
3292@noindent
3293This is the same data, but displayed closer to System V conventions:
3294
3295@smallexample
3296$ size --format=SysV ranlib size
3297ranlib :
3298section size addr
3299.text 294880 8192
3300.data 81920 303104
3301.bss 11592 385024
3302Total 388392
3303
3304
3305size :
3306section size addr
3307.text 294880 8192
3308.data 81920 303104
3309.bss 11888 385024
3310Total 388688
3311@end smallexample
3312
3313@item --help
3314@itemx -h
3315@itemx -H
3316@item -?
3317Show a summary of acceptable arguments and options.
3318
3319@item -d
3320@itemx -o
3321@itemx -x
3322@itemx --radix=@var{number}
3323@cindex @command{size} number format
3324@cindex radix for section sizes
3325Using one of these options, you can control whether the size of each
3326section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3327(@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3328@option{--radix=16}). In @option{--radix=@var{number}}, only the three
3329values (8, 10, 16) are supported. The total size is always given in two
3330radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3331octal and hexadecimal if you're using @option{-o}.
3332
3333@item --common
3334Print total size of common symbols in each file. When using Berkeley
3335or GNU format these are included in the bss size.
3336
3337@item -t
3338@itemx --totals
3339Show totals of all objects listed (Berkeley or GNU format mode only).
3340
3341@item --target=@var{bfdname}
3342@cindex object code format
3343Specify that the object-code format for @var{objfile} is
3344@var{bfdname}. This option may not be necessary; @command{size} can
3345automatically recognize many formats.
3346@xref{Target Selection}, for more information.
3347
3348@item -v
3349@item -V
3350@itemx --version
3351Display the version number of @command{size}.
3352
3353@item -f
3354Ignored. This option is used by other versions of the @command{size}
3355program, but it is not supported by the GNU Binutils version.
3356
3357@end table
3358
3359@c man end
3360
3361@ignore
3362@c man begin SEEALSO size
3363ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3364@c man end
3365@end ignore
3366
3367@node strings
3368@chapter strings
3369@kindex strings
3370@cindex listings strings
3371@cindex printing strings
3372@cindex strings, printing
3373
3374@c man title strings print the sequences of printable characters in files
3375
3376@smallexample
3377@c man begin SYNOPSIS strings
3378strings [@option{-afovV}] [@option{-}@var{min-len}]
3379 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3380 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3381 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3382 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
3383 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3384 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3385 [@option{-w}] [@option{--include-all-whitespace}]
3386 [@option{-s}] [@option{--output-separator} @var{sep_string}]
3387 [@option{--help}] [@option{--version}] @var{file}@dots{}
3388@c man end
3389@end smallexample
3390
3391@c man begin DESCRIPTION strings
3392
3393For each @var{file} given, @sc{gnu} @command{strings} prints the
3394printable character sequences that are at least 4 characters long (or
3395the number given with the options below) and are followed by an
3396unprintable character.
3397
3398Depending upon how the strings program was configured it will default
3399to either displaying all the printable sequences that it can find in
3400each file, or only those sequences that are in loadable, initialized
3401data sections. If the file type is unrecognizable, or if strings is
3402reading from stdin then it will always display all of the printable
3403sequences that it can find.
3404
3405For backwards compatibility any file that occurs after a command-line
3406option of just @option{-} will also be scanned in full, regardless of
3407the presence of any @option{-d} option.
3408
3409@command{strings} is mainly useful for determining the contents of
3410non-text files.
3411
3412@c man end
3413
3414@c man begin OPTIONS strings
3415
3416@table @env
3417@item -a
3418@itemx --all
3419@itemx -
3420Scan the whole file, regardless of what sections it contains or
3421whether those sections are loaded or initialized. Normally this is
3422the default behaviour, but strings can be configured so that the
3423@option{-d} is the default instead.
3424
3425The @option{-} option is position dependent and forces strings to
3426perform full scans of any file that is mentioned after the @option{-}
3427on the command line, even if the @option{-d} option has been
3428specified.
3429
3430@item -d
3431@itemx --data
3432Only print strings from initialized, loaded data sections in the
3433file. This may reduce the amount of garbage in the output, but it
3434also exposes the strings program to any security flaws that may be
3435present in the BFD library used to scan and load sections. Strings
3436can be configured so that this option is the default behaviour. In
3437such cases the @option{-a} option can be used to avoid using the BFD
3438library and instead just print all of the strings found in the file.
3439
3440@item -f
3441@itemx --print-file-name
3442Print the name of the file before each string.
3443
3444@item --help
3445Print a summary of the program usage on the standard output and exit.
3446
3447@item -@var{min-len}
3448@itemx -n @var{min-len}
3449@itemx --bytes=@var{min-len}
3450Print sequences of displayable characters that are at least
3451@var{min-len} characters long. If not specified a default minimum
3452length of 4 is used. The distinction between displayable and
3453non-displayable characters depends upon the setting of the
3454@option{-e} and @option{-U} options. Sequences are always terminated
3455at control characters such as new-line and carriage-return, but not
3456the tab character.
3457
3458@item -o
3459Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3460act like @samp{-t d} instead. Since we can not be compatible with both
3461ways, we simply chose one.
3462
3463@item -t @var{radix}
3464@itemx --radix=@var{radix}
3465Print the offset within the file before each string. The single
3466character argument specifies the radix of the offset---@samp{o} for
3467octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3468
3469@item -e @var{encoding}
3470@itemx --encoding=@var{encoding}
3471Select the character encoding of the strings that are to be found.
3472Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3473characters (default), @samp{S} =
3474single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
347516-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3476littleendian. Useful for finding wide character strings. (@samp{l}
3477and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3478
3479@item -U @var{[d|i|l|e|x|h]}
3480@itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3481Controls the display of UTF-8 encoded multibyte characters in strings.
3482The default (@option{--unicode=default}) is to give them no special
3483treatment, and instead rely upon the setting of the
3484@option{--encoding} option. The other values for this option
3485automatically enable @option{--encoding=S}.
3486
3487The @option{--unicode=invalid} option treats them as non-graphic
3488characters and hence not part of a valid string. All the remaining
3489options treat them as valid string characters.
3490
3491The @option{--unicode=locale} option displays them in the current
3492locale, which may or may not support UTF-8 encoding. The
3493@option{--unicode=hex} option displays them as hex byte sequences
3494enclosed between @var{<>} characters. The @option{--unicode=escape}
3495option displays them as escape sequences (@var{\uxxxx}) and the
3496@option{--unicode=highlight} option displays them as escape sequences
3497highlighted in red (if supported by the output device). The colouring
3498is intended to draw attention to the presence of unicode sequences
3499where they might not be expected.
3500
3501@item -T @var{bfdname}
3502@itemx --target=@var{bfdname}
3503@cindex object code format
3504Specify an object code format other than your system's default format.
3505@xref{Target Selection}, for more information.
3506
3507@item -v
3508@itemx -V
3509@itemx --version
3510Print the program version number on the standard output and exit.
3511
3512@item -w
3513@itemx --include-all-whitespace
3514By default tab and space characters are included in the strings that
3515are displayed, but other whitespace characters, such a newlines and
3516carriage returns, are not. The @option{-w} option changes this so
3517that all whitespace characters are considered to be part of a string.
3518
3519@item -s
3520@itemx --output-separator
3521By default, output strings are delimited by a new-line. This option
3522allows you to supply any string to be used as the output record
3523separator. Useful with --include-all-whitespace where strings
3524may contain new-lines internally.
3525@end table
3526
3527@c man end
3528
3529@ignore
3530@c man begin SEEALSO strings
3531ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3532and the Info entries for @file{binutils}.
3533@c man end
3534@end ignore
3535
3536@node strip
3537@chapter strip
3538
3539@kindex strip
3540@cindex removing symbols
3541@cindex discarding symbols
3542@cindex symbols, discarding
3543
3544@c man title strip discard symbols and other data from object files
3545
3546@smallexample
3547@c man begin SYNOPSIS strip
3548strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3549 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3550 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3551 [@option{-s}|@option{--strip-all}]
3552 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3553 [@option{--strip-dwo}]
3554 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3555 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3556 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3557 [@option{-w}|@option{--wildcard}]
3558 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3559 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3560 [@option{--keep-section=}@var{sectionpattern}]
3561 [@option{--remove-relocations=}@var{sectionpattern}]
3562 [@option{--strip-section-headers}]
3563 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3564 [@option{-D}|@option{--enable-deterministic-archives}]
3565 [@option{-U}|@option{--disable-deterministic-archives}]
3566 [@option{--keep-section-symbols}]
3567 [@option{--keep-file-symbols}]
3568 [@option{--only-keep-debug}]
3569 [@option{--plugin} @var{name}]
3570 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3571 [@option{--help}] [@option{--info}]
3572 @var{objfile}@dots{}
3573@c man end
3574@end smallexample
3575
3576@c man begin DESCRIPTION strip
3577
3578@sc{gnu} @command{strip} discards all symbols from object files
3579@var{objfile}. The list of object files may include archives.
3580At least one object file must be given.
3581
3582@command{strip} modifies the files named in its argument,
3583rather than writing modified copies under different names.
3584
3585@c man end
3586
3587@c man begin OPTIONS strip
3588
3589@table @env
3590@item -F @var{bfdname}
3591@itemx --target=@var{bfdname}
3592Treat the original @var{objfile} as a file with the object
3593code format @var{bfdname}, and rewrite it in the same format.
3594@xref{Target Selection}, for more information.
3595
3596@item --help
3597Show a summary of the options to @command{strip} and exit.
3598
3599@item --info
3600Display a list showing all architectures and object formats available.
3601
3602@item -I @var{bfdname}
3603@itemx --input-target=@var{bfdname}
3604Treat the original @var{objfile} as a file with the object
3605code format @var{bfdname}.
3606@xref{Target Selection}, for more information.
3607
3608@item -O @var{bfdname}
3609@itemx --output-target=@var{bfdname}
3610Replace @var{objfile} with a file in the output format @var{bfdname}.
3611@xref{Target Selection}, for more information.
3612
3613@item -R @var{sectionname}
3614@itemx --remove-section=@var{sectionname}
3615Remove any section named @var{sectionname} from the output file, in
3616addition to whatever sections would otherwise be removed. This
3617option may be given more than once. Note that using this option
3618inappropriately may make the output file unusable. The wildcard
3619character @samp{*} may be given at the end of @var{sectionname}. If
3620so, then any section starting with @var{sectionname} will be removed.
3621
3622If the first character of @var{sectionpattern} is the exclamation
3623point (!) then matching sections will not be removed even if an
3624earlier use of @option{--remove-section} on the same command line
3625would otherwise remove it. For example:
3626
3627@smallexample
3628 --remove-section=.text.* --remove-section=!.text.foo
3629@end smallexample
3630
3631will remove all sections matching the pattern '.text.*', but will not
3632remove the section '.text.foo'.
3633
3634@item --keep-section=@var{sectionpattern}
3635When removing sections from the output file, keep sections that match
3636@var{sectionpattern}.
3637
3638@item --remove-relocations=@var{sectionpattern}
3639Remove relocations from the output file for any section matching
3640@var{sectionpattern}. This option may be given more than once. Note
3641that using this option inappropriately may make the output file
3642unusable. Wildcard characters are accepted in @var{sectionpattern}.
3643For example:
3644
3645@smallexample
3646 --remove-relocations=.text.*
3647@end smallexample
3648
3649will remove the relocations for all sections matching the patter
3650'.text.*'.
3651
3652If the first character of @var{sectionpattern} is the exclamation
3653point (!) then matching sections will not have their relocation
3654removed even if an earlier use of @option{--remove-relocations} on the
3655same command line would otherwise cause the relocations to be removed.
3656For example:
3657
3658@smallexample
3659 --remove-relocations=.text.* --remove-relocations=!.text.foo
3660@end smallexample
3661
3662will remove all relocations for sections matching the pattern
3663'.text.*', but will not remove relocations for the section
3664'.text.foo'.
3665
3666@item --strip-section-headers
3667Strip section headers. This option is specific to ELF files. Implies
3668@option{--strip-all} and @option{--merge-notes}.
3669
3670@item -s
3671@itemx --strip-all
3672Remove all symbols.
3673
3674@item -g
3675@itemx -S
3676@itemx -d
3677@itemx --strip-debug
3678Remove debugging symbols only.
3679
3680@item --strip-dwo
3681Remove the contents of all DWARF .dwo sections, leaving the
3682remaining debugging sections and all symbols intact.
3683See the description of this option in the @command{objcopy} section
3684for more information.
3685
3686@item --strip-unneeded
3687Remove all symbols that are not needed for relocation processing in
3688addition to debugging symbols and sections stripped by
3689@option{--strip-debug}.
3690
3691@item -K @var{symbolname}
3692@itemx --keep-symbol=@var{symbolname}
3693When stripping symbols, keep symbol @var{symbolname} even if it would
3694normally be stripped. This option may be given more than once.
3695
3696@item -M
3697@itemx --merge-notes
3698@itemx --no-merge-notes
3699For ELF files, attempt (or do not attempt) to reduce the size of any
3700SHT_NOTE type sections by removing duplicate notes. The default is to
3701attempt this reduction unless stripping debug or DWO information.
3702
3703@item -N @var{symbolname}
3704@itemx --strip-symbol=@var{symbolname}
3705Remove symbol @var{symbolname} from the source file. This option may be
3706given more than once, and may be combined with strip options other than
3707@option{-K}.
3708
3709@item -o @var{file}
3710Put the stripped output in @var{file}, rather than replacing the
3711existing file. When this argument is used, only one @var{objfile}
3712argument may be specified.
3713
3714@item -p
3715@itemx --preserve-dates
3716Preserve the access and modification dates of the file.
3717
3718@item -D
3719@itemx --enable-deterministic-archives
3720@cindex deterministic archives
3721@kindex --enable-deterministic-archives
3722Operate in @emph{deterministic} mode. When copying archive members
3723and writing the archive index, use zero for UIDs, GIDs, timestamps,
3724and use consistent file modes for all files.
3725
3726If @file{binutils} was configured with
3727@option{--enable-deterministic-archives}, then this mode is on by default.
3728It can be disabled with the @samp{-U} option, below.
3729
3730@item -U
3731@itemx --disable-deterministic-archives
3732@cindex deterministic archives
3733@kindex --enable-deterministic-archives
3734Do @emph{not} operate in @emph{deterministic} mode. This is the
3735inverse of the @option{-D} option, above: when copying archive members
3736and writing the archive index, use their actual UID, GID, timestamp,
3737and file mode values.
3738
3739This is the default unless @file{binutils} was configured with
3740@option{--enable-deterministic-archives}.
3741
3742@item -w
3743@itemx --wildcard
3744Permit regular expressions in @var{symbolname}s used in other command
3745line options. The question mark (?), asterisk (*), backslash (\) and
3746square brackets ([]) operators can be used anywhere in the symbol
3747name. If the first character of the symbol name is the exclamation
3748point (!) then the sense of the switch is reversed for that symbol.
3749For example:
3750
3751@smallexample
3752 -w -K !foo -K fo*
3753@end smallexample
3754
3755would cause strip to only keep symbols that start with the letters
3756``fo'', but to discard the symbol ``foo''.
3757
3758@item -x
3759@itemx --discard-all
3760Remove non-global symbols.
3761
3762@item -X
3763@itemx --discard-locals
3764Remove compiler-generated local symbols.
3765(These usually start with @samp{L} or @samp{.}.)
3766
3767@item --keep-section-symbols
3768When stripping a file, perhaps with @option{--strip-debug} or
3769@option{--strip-unneeded}, retain any symbols specifying section names,
3770which would otherwise get stripped.
3771
3772@item --keep-file-symbols
3773When stripping a file, perhaps with @option{--strip-debug} or
3774@option{--strip-unneeded}, retain any symbols specifying source file names,
3775which would otherwise get stripped.
3776
3777@item --only-keep-debug
3778Strip a file, emptying the contents of any sections that would not be
3779stripped by @option{--strip-debug} and leaving the debugging sections
3780intact. In ELF files, this preserves all the note sections in the
3781output as well.
3782
3783Note - the section headers of the stripped sections are preserved,
3784including their sizes, but the contents of the section are discarded.
3785The section headers are preserved so that other tools can match up the
3786debuginfo file with the real executable, even if that executable has
3787been relocated to a different address space.
3788
3789The intention is that this option will be used in conjunction with
3790@option{--add-gnu-debuglink} to create a two part executable. One a
3791stripped binary which will occupy less space in RAM and in a
3792distribution and the second a debugging information file which is only
3793needed if debugging abilities are required. The suggested procedure
3794to create these files is as follows:
3795
3796@enumerate
3797@item Link the executable as normal. Assuming that it is called
3798@code{foo} then...
3799@item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3800create a file containing the debugging info.
3801@item Run @code{objcopy --strip-debug foo} to create a
3802stripped executable.
3803@item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3804to add a link to the debugging info into the stripped executable.
3805@end enumerate
3806
3807Note---the choice of @code{.dbg} as an extension for the debug info
3808file is arbitrary. Also the @code{--only-keep-debug} step is
3809optional. You could instead do this:
3810
3811@enumerate
3812@item Link the executable as normal.
3813@item Copy @code{foo} to @code{foo.full}
3814@item Run @code{strip --strip-debug foo}
3815@item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3816@end enumerate
3817
3818i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3819full executable. It does not have to be a file created by the
3820@option{--only-keep-debug} switch.
3821
3822Note---this switch is only intended for use on fully linked files. It
3823does not make sense to use it on object files where the debugging
3824information may be incomplete. Besides the gnu_debuglink feature
3825currently only supports the presence of one filename containing
3826debugging information, not multiple filenames on a one-per-object-file
3827basis.
3828
3829@item --plugin @var{name}
3830@cindex plugins
3831Load the plugin called @var{name} to add support for extra target
3832types. This option is only available if the toolchain has been built
3833with plugin support enabled.
3834
3835If @option{--plugin} is not provided, but plugin support has been
3836enabled then @command{strip} iterates over the files in
3837@file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
3838plugin that claims the object in question is used.
3839
3840Please note that this plugin search directory is @emph{not} the one
3841used by @command{ld}'s @option{-plugin} option. In order to make
3842@command{strip} use the linker plugin it must be copied into the
3843@file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
3844the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
3845based compilations it is called @file{LLVMgold.so}. The GCC plugin
3846is always backwards compatible with earlier versions, so it is
3847sufficient to just copy the newest one.
3848
3849@item -V
3850@itemx --version
3851Show the version number for @command{strip}.
3852
3853@item -v
3854@itemx --verbose
3855Verbose output: list all object files modified. In the case of
3856archives, @samp{strip -v} lists all members of the archive.
3857@end table
3858
3859@c man end
3860
3861@ignore
3862@c man begin SEEALSO strip
3863the Info entries for @file{binutils}.
3864@c man end
3865@end ignore
3866
3867@node c++filt, addr2line, strip, Top
3868@chapter c++filt
3869
3870@kindex c++filt
3871@cindex demangling C++ symbols
3872
3873@c man title cxxfilt demangle C++ and Java symbols
3874
3875@smallexample
3876@c man begin SYNOPSIS cxxfilt
3877c++filt [@option{-_}|@option{--strip-underscore}]
3878 [@option{-n}|@option{--no-strip-underscore}]
3879 [@option{-p}|@option{--no-params}]
3880 [@option{-t}|@option{--types}]
3881 [@option{-i}|@option{--no-verbose}]
3882 [@option{-r}|@option{--no-recurse-limit}]
3883 [@option{-R}|@option{--recurse-limit}]
3884 [@option{-s} @var{format}|@option{--format=}@var{format}]
3885 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3886@c man end
3887@end smallexample
3888
3889@c man begin DESCRIPTION cxxfilt
3890
3891@kindex cxxfilt
3892The C++ and Java languages provide function overloading, which means
3893that you can write many functions with the same name, providing that
3894each function takes parameters of different types. In order to be
3895able to distinguish these similarly named functions C++ and Java
3896encode them into a low-level assembler name which uniquely identifies
3897each different version. This process is known as @dfn{mangling}. The
3898@command{c++filt}
3899@footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3900MS-DOS this program is named @command{CXXFILT}.}
3901program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3902names into user-level names so that they can be read.
3903
3904Every alphanumeric word (consisting of letters, digits, underscores,
3905dollars, or periods) seen in the input is a potential mangled name.
3906If the name decodes into a C++ name, the C++ name replaces the
3907low-level name in the output, otherwise the original word is output.
3908In this way you can pass an entire assembler source file, containing
3909mangled names, through @command{c++filt} and see the same source file
3910containing demangled names.
3911
3912You can also use @command{c++filt} to decipher individual symbols by
3913passing them on the command line:
3914
3915@example
3916c++filt @var{symbol}
3917@end example
3918
3919If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3920names from the standard input instead. All the results are printed on
3921the standard output. The difference between reading names from the
3922command line versus reading names from the standard input is that
3923command-line arguments are expected to be just mangled names and no
3924checking is performed to separate them from surrounding text. Thus
3925for example:
3926
3927@smallexample
3928c++filt -n _Z1fv
3929@end smallexample
3930
3931will work and demangle the name to ``f()'' whereas:
3932
3933@smallexample
3934c++filt -n _Z1fv,
3935@end smallexample
3936
3937will not work. (Note the extra comma at the end of the mangled
3938name which makes it invalid). This command however will work:
3939
3940@smallexample
3941echo _Z1fv, | c++filt -n
3942@end smallexample
3943
3944and will display ``f(),'', i.e., the demangled name followed by a
3945trailing comma. This behaviour is because when the names are read
3946from the standard input it is expected that they might be part of an
3947assembler source file where there might be extra, extraneous
3948characters trailing after a mangled name. For example:
3949
3950@smallexample
3951 .type _Z1fv, @@function
3952@end smallexample
3953
3954@c man end
3955
3956@c man begin OPTIONS cxxfilt
3957
3958@table @env
3959@item -_
3960@itemx --strip-underscore
3961On some systems, both the C and C++ compilers put an underscore in front
3962of every name. For example, the C name @code{foo} gets the low-level
3963name @code{_foo}. This option removes the initial underscore. Whether
3964@command{c++filt} removes the underscore by default is target dependent.
3965
3966@item -n
3967@itemx --no-strip-underscore
3968Do not remove the initial underscore.
3969
3970@item -p
3971@itemx --no-params
3972When demangling the name of a function, do not display the types of
3973the function's parameters.
3974
3975@item -t
3976@itemx --types
3977Attempt to demangle types as well as function names. This is disabled
3978by default since mangled types are normally only used internally in
3979the compiler, and they can be confused with non-mangled names. For example,
3980a function called ``a'' treated as a mangled type name would be
3981demangled to ``signed char''.
3982
3983@item -i
3984@itemx --no-verbose
3985Do not include implementation details (if any) in the demangled
3986output.
3987
3988@item -r
3989@itemx -R
3990@itemx --recurse-limit
3991@itemx --no-recurse-limit
3992@itemx --recursion-limit
3993@itemx --no-recursion-limit
3994Enables or disables a limit on the amount of recursion performed
3995whilst demangling strings. Since the name mangling formats allow for
3996an infinite level of recursion it is possible to create strings whose
3997decoding will exhaust the amount of stack space available on the host
3998machine, triggering a memory fault. The limit tries to prevent this
3999from happening by restricting recursion to 2048 levels of nesting.
4000
4001The default is for this limit to be enabled, but disabling it may be
4002necessary in order to demangle truly complicated names. Note however
4003that if the recursion limit is disabled then stack exhaustion is
4004possible and any bug reports about such an event will be rejected.
4005
4006The @option{-r} option is a synonym for the
4007@option{--no-recurse-limit} option. The @option{-R} option is a
4008synonym for the @option{--recurse-limit} option.
4009
4010@item -s @var{format}
4011@itemx --format=@var{format}
4012@command{c++filt} can decode various methods of mangling, used by
4013different compilers. The argument to this option selects which
4014method it uses:
4015
4016@table @code
4017@item auto
4018Automatic selection based on executable (the default method)
4019@item gnu
4020the one used by the @sc{gnu} C++ compiler (g++)
4021@item lucid
4022the one used by the Lucid compiler (lcc)
4023@item arm
4024the one specified by the C++ Annotated Reference Manual
4025@item hp
4026the one used by the HP compiler (aCC)
4027@item edg
4028the one used by the EDG compiler
4029@item gnu-v3
4030the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
4031@item java
4032the one used by the @sc{gnu} Java compiler (gcj)
4033@item gnat
4034the one used by the @sc{gnu} Ada compiler (GNAT).
4035@end table
4036
4037@item --help
4038Print a summary of the options to @command{c++filt} and exit.
4039
4040@item --version
4041Print the version number of @command{c++filt} and exit.
4042@end table
4043
4044@c man end
4045
4046@ignore
4047@c man begin SEEALSO cxxfilt
4048the Info entries for @file{binutils}.
4049@c man end
4050@end ignore
4051
4052@quotation
4053@emph{Warning:} @command{c++filt} is a new utility, and the details of its
4054user interface are subject to change in future releases. In particular,
4055a command-line option may be required in the future to decode a name
4056passed as an argument on the command line; in other words,
4057
4058@example
4059c++filt @var{symbol}
4060@end example
4061
4062@noindent
4063may in a future release become
4064
4065@example
4066c++filt @var{option} @var{symbol}
4067@end example
4068@end quotation
4069
4070@node addr2line
4071@chapter addr2line
4072
4073@kindex addr2line
4074@cindex address to file name and line number
4075
4076@c man title addr2line convert addresses or symbol+offset into file names and line numbers
4077
4078@smallexample
4079@c man begin SYNOPSIS addr2line
4080addr2line [@option{-a}|@option{--addresses}]
4081 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
4082 [@option{-C}|@option{--demangle}[=@var{style}]]
4083 [@option{-r}|@option{--no-recurse-limit}]
4084 [@option{-R}|@option{--recurse-limit}]
4085 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
4086 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
4087 [@option{-i}|@option{--inlines}]
4088 [@option{-p}|@option{--pretty-print}]
4089 [@option{-j}|@option{--section=}@var{name}]
4090 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
4091 [addr addr @dots{}]
4092@c man end
4093@end smallexample
4094
4095@c man begin DESCRIPTION addr2line
4096
4097@command{addr2line} translates addresses or symbol+offset into file names and line numbers.
4098Given an address or symbol+offset in an executable or an offset in a section of a relocatable
4099object, it uses the debugging information to figure out which file name and
4100line number are associated with it.
4101
4102The executable or relocatable object to use is specified with the @option{-e}
4103option. The default is the file @file{a.out}. The section in the relocatable
4104object to use is specified with the @option{-j} option.
4105
4106@command{addr2line} has two modes of operation.
4107
4108In the first, hexadecimal addresses or symbol+offset are specified on the command line,
4109and @command{addr2line} displays the file name and line number for each
4110address.
4111
4112In the second, @command{addr2line} reads hexadecimal addresses or symbol+offset from
4113standard input, and prints the file name and line number for each
4114address on standard output. In this mode, @command{addr2line} may be used
4115in a pipe to convert dynamically chosen addresses.
4116
4117The format of the output is @samp{FILENAME:LINENO}. By default
4118each input address generates one line of output.
4119
4120Two options can generate additional lines before each
4121@samp{FILENAME:LINENO} line (in that order).
4122
4123If the @option{-a} option is used then a line with the input address
4124is displayed.
4125
4126If the @option{-f} option is used, then a line with the
4127@samp{FUNCTIONNAME} is displayed. This is the name of the function
4128containing the address.
4129
4130One option can generate additional lines after the
4131@samp{FILENAME:LINENO} line.
4132
4133If the @option{-i} option is used and the code at the given address is
4134present there because of inlining by the compiler then additional
4135lines are displayed afterwards. One or two extra lines (if the
4136@option{-f} option is used) are displayed for each inlined function.
4137
4138Alternatively if the @option{-p} option is used then each input
4139address generates a single, long, output line containing the address,
4140the function name, the file name and the line number. If the
4141@option{-i} option has also been used then any inlined functions will
4142be displayed in the same manner, but on separate lines, and prefixed
4143by the text @samp{(inlined by)}.
4144
4145If the file name or function name can not be determined,
4146@command{addr2line} will print two question marks in their place. If the
4147line number can not be determined, @command{addr2line} will print 0.
4148
4149When symbol+offset is used, +offset is optional, except when the symbol
4150is ambigious with a hex number. The resolved symbols can be mangled
4151or unmangled, except unmangled symbols with + are not allowed.
4152
4153@c man end
4154
4155@c man begin OPTIONS addr2line
4156
4157The long and short forms of options, shown here as alternatives, are
4158equivalent.
4159
4160@table @env
4161@item -a
4162@itemx --addresses
4163Display the address before the function name, file and line number
4164information. The address is printed with a @samp{0x} prefix to easily
4165identify it.
4166
4167@item -b @var{bfdname}
4168@itemx --target=@var{bfdname}
4169@cindex object code format
4170Specify that the object-code format for the object files is
4171@var{bfdname}.
4172
4173@item -C
4174@itemx --demangle[=@var{style}]
4175@cindex demangling in objdump
4176Decode (@dfn{demangle}) low-level symbol names into user-level names.
4177Besides removing any initial underscore prepended by the system, this
4178makes C++ function names readable. Different compilers have different
4179mangling styles. The optional demangling style argument can be used to
4180choose an appropriate demangling style for your compiler. @xref{c++filt},
4181for more information on demangling.
4182
4183@item -e @var{filename}
4184@itemx --exe=@var{filename}
4185Specify the name of the executable for which addresses should be
4186translated. The default file is @file{a.out}.
4187
4188@item -f
4189@itemx --functions
4190Display function names as well as file and line number information.
4191
4192@item -s
4193@itemx --basenames
4194Display only the base of each file name.
4195
4196@item -i
4197@itemx --inlines
4198If the address belongs to a function that was inlined, the source
4199information for all enclosing scopes back to the first non-inlined
4200function will also be printed. For example, if @code{main} inlines
4201@code{callee1} which inlines @code{callee2}, and address is from
4202@code{callee2}, the source information for @code{callee1} and @code{main}
4203will also be printed.
4204
4205@item -j
4206@itemx --section
4207Read offsets relative to the specified section instead of absolute addresses.
4208
4209@item -p
4210@itemx --pretty-print
4211Make the output more human friendly: each location are printed on one line.
4212If option @option{-i} is specified, lines for all enclosing scopes are
4213prefixed with @samp{(inlined by)}.
4214
4215@item -r
4216@itemx -R
4217@itemx --recurse-limit
4218@itemx --no-recurse-limit
4219@itemx --recursion-limit
4220@itemx --no-recursion-limit
4221Enables or disables a limit on the amount of recursion performed
4222whilst demangling strings. Since the name mangling formats allow for
4223an infinite level of recursion it is possible to create strings whose
4224decoding will exhaust the amount of stack space available on the host
4225machine, triggering a memory fault. The limit tries to prevent this
4226from happening by restricting recursion to 2048 levels of nesting.
4227
4228The default is for this limit to be enabled, but disabling it may be
4229necessary in order to demangle truly complicated names. Note however
4230that if the recursion limit is disabled then stack exhaustion is
4231possible and any bug reports about such an event will be rejected.
4232
4233The @option{-r} option is a synonym for the
4234@option{--no-recurse-limit} option. The @option{-R} option is a
4235synonym for the @option{--recurse-limit} option.
4236
4237Note this option is only effective if the @option{-C} or
4238@option{--demangle} option has been enabled.
4239
4240@end table
4241
4242@c man end
4243
4244@ignore
4245@c man begin SEEALSO addr2line
4246Info entries for @file{binutils}.
4247@c man end
4248@end ignore
4249
4250@node windmc
4251@chapter windmc
4252
4253@command{windmc} may be used to generator Windows message resources.
4254
4255@quotation
4256@emph{Warning:} @command{windmc} is not always built as part of the binary
4257utilities, since it is only useful for Windows targets.
4258@end quotation
4259
4260@c man title windmc generates Windows message resources
4261
4262@smallexample
4263@c man begin SYNOPSIS windmc
4264windmc [options] input-file
4265@c man end
4266@end smallexample
4267
4268@c man begin DESCRIPTION windmc
4269
4270@command{windmc} reads message definitions from an input file (.mc) and
4271translate them into a set of output files. The output files may be of
4272four kinds:
4273
4274@table @code
4275@item h
4276A C header file containing the message definitions.
4277
4278@item rc
4279A resource file compilable by the @command{windres} tool.
4280
4281@item bin
4282One or more binary files containing the resource data for a specific
4283message language.
4284
4285@item dbg
4286A C include file that maps message id's to their symbolic name.
4287@end table
4288
4289The exact description of these different formats is available in
4290documentation from Microsoft.
4291
4292When @command{windmc} converts from the @code{mc} format to the @code{bin}
4293format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
4294Windows Message Compiler.
4295
4296@c man end
4297
4298@c man begin OPTIONS windmc
4299
4300@table @env
4301@item -a
4302@itemx --ascii_in
4303Specifies that the input file specified is ASCII. This is the default
4304behaviour.
4305
4306@item -A
4307@itemx --ascii_out
4308Specifies that messages in the output @code{bin} files should be in ASCII
4309format.
4310
4311@item -b
4312@itemx --binprefix
4313Specifies that @code{bin} filenames should have to be prefixed by the
4314basename of the source file.
4315
4316@item -c
4317@itemx --customflag
4318Sets the customer bit in all message id's.
4319
4320@item -C @var{codepage}
4321@itemx --codepage_in @var{codepage}
4322Sets the default codepage to be used to convert input file to UTF16. The
4323default is ocdepage 1252.
4324
4325@item -d
4326@itemx --decimal_values
4327Outputs the constants in the header file in decimal. Default is using
4328hexadecimal output.
4329
4330@item -e @var{ext}
4331@itemx --extension @var{ext}
4332The extension for the header file. The default is .h extension.
4333
4334@item -F @var{target}
4335@itemx --target @var{target}
4336Specify the BFD format to use for a bin file as output. This
4337is a BFD target name; you can use the @option{--help} option to see a list
4338of supported targets. Normally @command{windmc} will use the default
4339format, which is the first one listed by the @option{--help} option.
4340@ifclear man
4341@ref{Target Selection}.
4342@end ifclear
4343
4344@item -h @var{path}
4345@itemx --headerdir @var{path}
4346The target directory of the generated header file. The default is the
4347current directory.
4348
4349@item -H
4350@itemx --help
4351Displays a list of command-line options and then exits.
4352
4353@item -m @var{characters}
4354@itemx --maxlength @var{characters}
4355Instructs @command{windmc} to generate a warning if the length
4356of any message exceeds the number specified.
4357
4358@item -n
4359@itemx --nullterminate
4360Terminate message text in @code{bin} files by zero. By default they are
4361terminated by CR/LF.
4362
4363@item -o
4364@itemx --hresult_use
4365Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4366file, using HRESULT definitions. Status codes are used if the flag is not
4367specified.
4368
4369@item -O @var{codepage}
4370@itemx --codepage_out @var{codepage}
4371Sets the default codepage to be used to output text files. The default
4372is ocdepage 1252.
4373
4374@item -r @var{path}
4375@itemx --rcdir @var{path}
4376The target directory for the generated @code{rc} script and the generated
4377@code{bin} files that the resource compiler script includes. The default
4378is the current directory.
4379
4380@item -u
4381@itemx --unicode_in
4382Specifies that the input file is UTF16.
4383
4384@item -U
4385@itemx --unicode_out
4386Specifies that messages in the output @code{bin} file should be in UTF16
4387format. This is the default behaviour.
4388
4389@item -v
4390@item --verbose
4391Enable verbose mode.
4392
4393@item -V
4394@item --version
4395Prints the version number for @command{windmc}.
4396
4397@item -x @var{path}
4398@itemx --xdgb @var{path}
4399The path of the @code{dbg} C include file that maps message id's to the
4400symbolic name. No such file is generated without specifying the switch.
4401@end table
4402
4403@c man end
4404
4405@ignore
4406@c man begin SEEALSO windmc
4407the Info entries for @file{binutils}.
4408@c man end
4409@end ignore
4410
4411@node windres
4412@chapter windres
4413
4414@command{windres} may be used to manipulate Windows resources.
4415
4416@quotation
4417@emph{Warning:} @command{windres} is not always built as part of the binary
4418utilities, since it is only useful for Windows targets.
4419@end quotation
4420
4421@c man title windres manipulate Windows resources
4422
4423@smallexample
4424@c man begin SYNOPSIS windres
4425windres [options] [input-file] [output-file]
4426@c man end
4427@end smallexample
4428
4429@c man begin DESCRIPTION windres
4430
4431@command{windres} reads resources from an input file and copies them into
4432an output file. Either file may be in one of three formats:
4433
4434@table @code
4435@item rc
4436A text format read by the Resource Compiler.
4437
4438@item res
4439A binary format generated by the Resource Compiler.
4440
4441@item coff
4442A COFF object or executable.
4443@end table
4444
4445The exact description of these different formats is available in
4446documentation from Microsoft.
4447
4448When @command{windres} converts from the @code{rc} format to the @code{res}
4449format, it is acting like the Windows Resource Compiler. When
4450@command{windres} converts from the @code{res} format to the @code{coff}
4451format, it is acting like the Windows @code{CVTRES} program.
4452
4453When @command{windres} generates an @code{rc} file, the output is similar
4454but not identical to the format expected for the input. When an input
4455@code{rc} file refers to an external filename, an output @code{rc} file
4456will instead include the file contents.
4457
4458If the input or output format is not specified, @command{windres} will
4459guess based on the file name, or, for the input file, the file contents.
4460A file with an extension of @file{.rc} will be treated as an @code{rc}
4461file, a file with an extension of @file{.res} will be treated as a
4462@code{res} file, and a file with an extension of @file{.o} or
4463@file{.exe} will be treated as a @code{coff} file.
4464
4465If no output file is specified, @command{windres} will print the resources
4466in @code{rc} format to standard output.
4467
4468The normal use is for you to write an @code{rc} file, use @command{windres}
4469to convert it to a COFF object file, and then link the COFF file into
4470your application. This will make the resources described in the
4471@code{rc} file available to Windows.
4472
4473@c man end
4474
4475@c man begin OPTIONS windres
4476
4477@table @env
4478@item -i @var{filename}
4479@itemx --input @var{filename}
4480The name of the input file. If this option is not used, then
4481@command{windres} will use the first non-option argument as the input file
4482name. If there are no non-option arguments, then @command{windres} will
4483read from standard input. @command{windres} can not read a COFF file from
4484standard input.
4485
4486@item -o @var{filename}
4487@itemx --output @var{filename}
4488The name of the output file. If this option is not used, then
4489@command{windres} will use the first non-option argument, after any used
4490for the input file name, as the output file name. If there is no
4491non-option argument, then @command{windres} will write to standard output.
4492@command{windres} can not write a COFF file to standard output. Note,
4493for compatibility with @command{rc} the option @option{-fo} is also
4494accepted, but its use is not recommended.
4495
4496@item -J @var{format}
4497@itemx --input-format @var{format}
4498The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4499@samp{coff}. If no input format is specified, @command{windres} will
4500guess, as described above.
4501
4502@item -O @var{format}
4503@itemx --output-format @var{format}
4504The output format to generate. @var{format} may be @samp{res},
4505@samp{rc}, or @samp{coff}. If no output format is specified,
4506@command{windres} will guess, as described above.
4507
4508@item -F @var{target}
4509@itemx --target @var{target}
4510Specify the BFD format to use for a COFF file as input or output. This
4511is a BFD target name; you can use the @option{--help} option to see a list
4512of supported targets. Normally @command{windres} will use the default
4513format, which is the first one listed by the @option{--help} option.
4514@ifclear man
4515@ref{Target Selection}.
4516@end ifclear
4517
4518@item --preprocessor @var{program}
4519When @command{windres} reads an @code{rc} file, it runs it through the C
4520preprocessor first. This option may be used to specify the preprocessor
4521to use. The default preprocessor is @code{gcc}.
4522
4523@item --preprocessor-arg @var{option}
4524When @command{windres} reads an @code{rc} file, it runs it through
4525the C preprocessor first. This option may be used to specify additional
4526text to be passed to preprocessor on its command line.
4527This option can be used multiple times to add multiple options to the
4528preprocessor command line.
4529If the @option{--preprocessor} option has not been specified then a
4530default set of preprocessor arguments will be used, with any
4531@option{--preprocessor-arg} options being placed after them on the
4532command line. These default arguments are @code{-E},
4533@code{-xc-header} and @code{-DRC_INVOKED}.
4534
4535@item -I @var{directory}
4536@itemx --include-dir @var{directory}
4537Specify an include directory to use when reading an @code{rc} file.
4538@command{windres} will pass this to the preprocessor as an @option{-I}
4539option. @command{windres} will also search this directory when looking for
4540files named in the @code{rc} file. If the argument passed to this command
4541matches any of the supported @var{formats} (as described in the @option{-J}
4542option), it will issue a deprecation warning, and behave just like the
4543@option{-J} option. New programs should not use this behaviour. If a
4544directory happens to match a @var{format}, simple prefix it with @samp{./}
4545to disable the backward compatibility.
4546
4547@item -D @var{target}
4548@itemx --define @var{sym}[=@var{val}]
4549Specify a @option{-D} option to pass to the preprocessor when reading an
4550@code{rc} file.
4551
4552@item -U @var{target}
4553@itemx --undefine @var{sym}
4554Specify a @option{-U} option to pass to the preprocessor when reading an
4555@code{rc} file.
4556
4557@item -r
4558Ignored for compatibility with rc.
4559
4560@item -v
4561Enable verbose mode. This tells you what the preprocessor is if you
4562didn't specify one.
4563
4564@item -c @var{val}
4565@item --codepage @var{val}
4566Specify the default codepage to use when reading an @code{rc} file.
4567@var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4568codepage code. The valid range is from zero up to 0xffff, but the
4569validity of the codepage is host and configuration dependent.
4570
4571@item -l @var{val}
4572@item --language @var{val}
4573Specify the default language to use when reading an @code{rc} file.
4574@var{val} should be a hexadecimal language code. The low eight bits are
4575the language, and the high eight bits are the sublanguage.
4576
4577@item --use-temp-file
4578Use a temporary file to instead of using popen to read the output of
4579the preprocessor. Use this option if the popen implementation is buggy
4580on the host (eg., certain non-English language versions of Windows 95 and
4581Windows 98 are known to have buggy popen where the output will instead
4582go the console).
4583
4584@item --no-use-temp-file
4585Use popen, not a temporary file, to read the output of the preprocessor.
4586This is the default behaviour.
4587
4588@item -h
4589@item --help
4590Prints a usage summary.
4591
4592@item -V
4593@item --version
4594Prints the version number for @command{windres}.
4595
4596@item --yydebug
4597If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4598this will turn on parser debugging.
4599@end table
4600
4601@c man end
4602
4603@ignore
4604@c man begin SEEALSO windres
4605the Info entries for @file{binutils}.
4606@c man end
4607@end ignore
4608
4609@node dlltool
4610@chapter dlltool
4611@cindex DLL
4612@kindex dlltool
4613
4614@command{dlltool} is used to create the files needed to create dynamic
4615link libraries (DLLs) on systems which understand PE format image
4616files such as Windows. A DLL contains an export table which contains
4617information that the runtime loader needs to resolve references from a
4618referencing program.
4619
4620The export table is generated by this program by reading in a
4621@file{.def} file or scanning the @file{.a} and @file{.o} files which
4622will be in the DLL. A @file{.o} file can contain information in
4623special @samp{.drectve} sections with export information.
4624
4625@quotation
4626@emph{Note:} @command{dlltool} is not always built as part of the
4627binary utilities, since it is only useful for those targets which
4628support DLLs.
4629@end quotation
4630
4631@c man title dlltool create files needed to build and use DLLs
4632
4633@smallexample
4634@c man begin SYNOPSIS dlltool
4635dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4636 [@option{-b}|@option{--base-file} @var{base-file-name}]
4637 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4638 [@option{-z}|@option{--output-def} @var{def-file-name}]
4639 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4640 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4641 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4642 [@option{--exclude-symbols} @var{list}]
4643 [@option{--no-default-excludes}]
4644 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4645 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4646 [@option{-a}|@option{--add-indirect}]
4647 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4648 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4649 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4650 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4651 [@option{--use-nul-prefixed-import-tables}]
4652 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4653 [@option{-i}|@option{--interwork}]
4654 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4655 [@option{-v}|@option{--verbose}]
4656 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4657 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4658 [@option{--deterministic-libraries}] [@option{--non-deterministic-libraries}]
4659 [object-file @dots{}]
4660@c man end
4661@end smallexample
4662
4663@c man begin DESCRIPTION dlltool
4664
4665@command{dlltool} reads its inputs, which can come from the @option{-d} and
4666@option{-b} options as well as object files specified on the command
4667line. It then processes these inputs and if the @option{-e} option has
4668been specified it creates a exports file. If the @option{-l} option
4669has been specified it creates a library file and if the @option{-z} option
4670has been specified it creates a def file. Any or all of the @option{-e},
4671@option{-l} and @option{-z} options can be present in one invocation of
4672dlltool.
4673
4674When creating a DLL, along with the source for the DLL, it is necessary
4675to have three other files. @command{dlltool} can help with the creation of
4676these files.
4677
4678The first file is a @file{.def} file which specifies which functions are
4679exported from the DLL, which functions the DLL imports, and so on. This
4680is a text file and can be created by hand, or @command{dlltool} can be used
4681to create it using the @option{-z} option. In this case @command{dlltool}
4682will scan the object files specified on its command line looking for
4683those functions which have been specially marked as being exported and
4684put entries for them in the @file{.def} file it creates.
4685
4686In order to mark a function as being exported from a DLL, it needs to
4687have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4688section of the object file. This can be done in C by using the
4689asm() operator:
4690
4691@smallexample
4692 asm (".section .drectve");
4693 asm (".ascii \"-export:my_func\"");
4694
4695 int my_func (void) @{ @dots{} @}
4696@end smallexample
4697
4698The second file needed for DLL creation is an exports file. This file
4699is linked with the object files that make up the body of the DLL and it
4700handles the interface between the DLL and the outside world. This is a
4701binary file and it can be created by giving the @option{-e} option to
4702@command{dlltool} when it is creating or reading in a @file{.def} file.
4703
4704The third file needed for DLL creation is the library file that programs
4705will link with in order to access the functions in the DLL (an `import
4706library'). This file can be created by giving the @option{-l} option to
4707dlltool when it is creating or reading in a @file{.def} file.
4708
4709If the @option{-y} option is specified, dlltool generates a delay-import
4710library that can be used instead of the normal import library to allow
4711a program to link to the dll only as soon as an imported function is
4712called for the first time. The resulting executable will need to be
4713linked to the static delayimp library containing __delayLoadHelper2(),
4714which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4715
4716@command{dlltool} builds the library file by hand, but it builds the
4717exports file by creating temporary files containing assembler statements
4718and then assembling these. The @option{-S} command-line option can be
4719used to specify the path to the assembler that dlltool will use,
4720and the @option{-f} option can be used to pass specific flags to that
4721assembler. The @option{-n} can be used to prevent dlltool from deleting
4722these temporary assembler files when it is done, and if @option{-n} is
4723specified twice then this will prevent dlltool from deleting the
4724temporary object files it used to build the library.
4725
4726Here is an example of creating a DLL from a source file @samp{dll.c} and
4727also creating a program (from an object file called @samp{program.o})
4728that uses that DLL:
4729
4730@smallexample
4731 gcc -c dll.c
4732 dlltool -e exports.o -l dll.lib dll.o
4733 gcc dll.o exports.o -o dll.dll
4734 gcc program.o dll.lib -o program
4735@end smallexample
4736
4737
4738@command{dlltool} may also be used to query an existing import library
4739to determine the name of the DLL to which it is associated. See the
4740description of the @option{-I} or @option{--identify} option.
4741
4742@c man end
4743
4744@c man begin OPTIONS dlltool
4745
4746The command-line options have the following meanings:
4747
4748@table @env
4749
4750@item -d @var{filename}
4751@itemx --input-def @var{filename}
4752@cindex input .def file
4753Specifies the name of a @file{.def} file to be read in and processed.
4754
4755@item -b @var{filename}
4756@itemx --base-file @var{filename}
4757@cindex base files
4758Specifies the name of a base file to be read in and processed. The
4759contents of this file will be added to the relocation section in the
4760exports file generated by dlltool.
4761
4762@item -e @var{filename}
4763@itemx --output-exp @var{filename}
4764Specifies the name of the export file to be created by dlltool.
4765
4766@item -z @var{filename}
4767@itemx --output-def @var{filename}
4768Specifies the name of the @file{.def} file to be created by dlltool.
4769
4770@item -l @var{filename}
4771@itemx --output-lib @var{filename}
4772Specifies the name of the library file to be created by dlltool.
4773
4774@item -y @var{filename}
4775@itemx --output-delaylib @var{filename}
4776Specifies the name of the delay-import library file to be created by dlltool.
4777
4778@item --deterministic-libraries
4779@itemx --non-deterministic-libraries
4780When creating output libraries in response to either the
4781@option{--output-lib} or @option{--output-delaylib} options either use
4782the value of zero for any timestamps, user ids and group ids created
4783(@option{--deterministic-libraries}) or the actual timestamps, user
4784ids and group ids (@option{--non-deterministic-libraries}).
4785
4786@item --export-all-symbols
4787Treat all global and weak defined symbols found in the input object
4788files as symbols to be exported. There is a small list of symbols which
4789are not exported by default; see the @option{--no-default-excludes}
4790option. You may add to the list of symbols to not export by using the
4791@option{--exclude-symbols} option.
4792
4793@item --no-export-all-symbols
4794Only export symbols explicitly listed in an input @file{.def} file or in
4795@samp{.drectve} sections in the input object files. This is the default
4796behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4797attributes in the source code.
4798
4799@item --exclude-symbols @var{list}
4800Do not export the symbols in @var{list}. This is a list of symbol names
4801separated by comma or colon characters. The symbol names should not
4802contain a leading underscore. This is only meaningful when
4803@option{--export-all-symbols} is used.
4804
4805@item --no-default-excludes
4806When @option{--export-all-symbols} is used, it will by default avoid
4807exporting certain special symbols. The current list of symbols to avoid
4808exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4809@samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4810to go ahead and export these special symbols. This is only meaningful
4811when @option{--export-all-symbols} is used.
4812
4813@item -S @var{path}
4814@itemx --as @var{path}
4815Specifies the path, including the filename, of the assembler to be used
4816to create the exports file.
4817
4818@item -f @var{options}
4819@itemx --as-flags @var{options}
4820Specifies any specific command-line options to be passed to the
4821assembler when building the exports file. This option will work even if
4822the @option{-S} option is not used. This option only takes one argument,
4823and if it occurs more than once on the command line, then later
4824occurrences will override earlier occurrences. So if it is necessary to
4825pass multiple options to the assembler they should be enclosed in
4826double quotes.
4827
4828@item -D @var{name}
4829@itemx --dll-name @var{name}
4830Specifies the name to be stored in the @file{.def} file as the name of
4831the DLL when the @option{-e} option is used. If this option is not
4832present, then the filename given to the @option{-e} option will be
4833used as the name of the DLL.
4834
4835@item -m @var{machine}
4836@itemx -machine @var{machine}
4837Specifies the type of machine for which the library file should be
4838built. @command{dlltool} has a built in default type, depending upon how
4839it was created, but this option can be used to override that. This is
4840normally only useful when creating DLLs for an ARM processor, when the
4841contents of the DLL are actually encode using Thumb instructions.
4842
4843@item -a
4844@itemx --add-indirect
4845Specifies that when @command{dlltool} is creating the exports file it
4846should add a section which allows the exported functions to be
4847referenced without using the import library. Whatever the hell that
4848means!
4849
4850@item -U
4851@itemx --add-underscore
4852Specifies that when @command{dlltool} is creating the exports file it
4853should prepend an underscore to the names of @emph{all} exported symbols.
4854
4855@item --no-leading-underscore
4856@item --leading-underscore
4857Specifies whether standard symbol should be forced to be prefixed, or
4858not.
4859
4860@item --add-stdcall-underscore
4861Specifies that when @command{dlltool} is creating the exports file it
4862should prepend an underscore to the names of exported @emph{stdcall}
4863functions. Variable names and non-stdcall function names are not modified.
4864This option is useful when creating GNU-compatible import libs for third
4865party DLLs that were built with MS-Windows tools.
4866
4867@item -k
4868@itemx --kill-at
4869Specifies that @samp{@@<number>} suffixes should be omitted from the names
4870of stdcall functions that will be imported from the DLL. This is
4871useful when creating an import library for a DLL which exports stdcall
4872functions but without the usual @samp{@@<number>} symbol name suffix.
4873
4874This does not change the naming of symbols provided by the import library
4875to programs linked against it, but only the entries in the import table
4876(ie the .idata section).
4877
4878@item -A
4879@itemx --add-stdcall-alias
4880Specifies that when @command{dlltool} is creating the exports file it
4881should add aliases for stdcall symbols without @samp{@@ <number>}
4882in addition to the symbols with @samp{@@ <number>}.
4883
4884@item -p
4885@itemx --ext-prefix-alias @var{prefix}
4886Causes @command{dlltool} to create external aliases for all DLL
4887imports with the specified prefix. The aliases are created for both
4888external and import symbols with no leading underscore.
4889
4890@item -x
4891@itemx --no-idata4
4892Specifies that when @command{dlltool} is creating the exports and library
4893files it should omit the @code{.idata4} section. This is for compatibility
4894with certain operating systems.
4895
4896@item --use-nul-prefixed-import-tables
4897Specifies that when @command{dlltool} is creating the exports and library
4898files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4899element. This emulates old gnu import library generation of
4900@code{dlltool}. By default this option is turned off.
4901
4902@item -c
4903@itemx --no-idata5
4904Specifies that when @command{dlltool} is creating the exports and library
4905files it should omit the @code{.idata5} section. This is for compatibility
4906with certain operating systems.
4907
4908@item -I @var{filename}
4909@itemx --identify @var{filename}
4910Specifies that @command{dlltool} should inspect the import library
4911indicated by @var{filename} and report, on @code{stdout}, the name(s)
4912of the associated DLL(s). This can be performed in addition to any
4913other operations indicated by the other options and arguments.
4914@command{dlltool} fails if the import library does not exist or is not
4915actually an import library. See also @option{--identify-strict}.
4916
4917@item --identify-strict
4918Modifies the behavior of the @option{--identify} option, such
4919that an error is reported if @var{filename} is associated with
4920more than one DLL.
4921
4922@item -i
4923@itemx --interwork
4924Specifies that @command{dlltool} should mark the objects in the library
4925file and exports file that it produces as supporting interworking
4926between ARM and Thumb code.
4927
4928@item -n
4929@itemx --nodelete
4930Makes @command{dlltool} preserve the temporary assembler files it used to
4931create the exports file. If this option is repeated then dlltool will
4932also preserve the temporary object files it uses to create the library
4933file.
4934
4935@item -t @var{prefix}
4936@itemx --temp-prefix @var{prefix}
4937Makes @command{dlltool} use @var{prefix} when constructing the names of
4938temporary assembler and object files. By default, the temp file prefix
4939is generated from the pid.
4940
4941@item -v
4942@itemx --verbose
4943Make dlltool describe what it is doing.
4944
4945@item -h
4946@itemx --help
4947Displays a list of command-line options and then exits.
4948
4949@item -V
4950@itemx --version
4951Displays dlltool's version number and then exits.
4952
4953@end table
4954
4955@c man end
4956
4957@menu
4958* def file format:: The format of the dlltool @file{.def} file
4959@end menu
4960
4961@node def file format
4962@section The format of the @command{dlltool} @file{.def} file
4963
4964A @file{.def} file contains any number of the following commands:
4965
4966@table @asis
4967
4968@item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4969The result is going to be named @var{name}@code{.exe}.
4970
4971@item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4972The result is going to be named @var{name}@code{.dll}.
4973Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4974this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4975details).
4976
4977@item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4978@item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4979Declares @var{name1} as an exported symbol from the DLL, with optional
4980ordinal number @var{integer}, or declares @var{name1} as an alias
4981(forward) of the function @var{external-name} in the DLL.
4982If @var{its_name} is specified, this name is used as string in export table.
4983@var{module-name}.
4984Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4985are treated - beside @code{LIBRARY} - as simple name-identifiers.
4986If you want to use LIBRARY as name then you need to quote it.
4987
4988@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{]} *}
4989Declares that @var{external-name} or the exported function whose
4990ordinal number is @var{integer} is to be imported from the file
4991@var{module-name}. If @var{internal-name} is specified then this is
4992the name that the imported function will be referred to in the body of
4993the DLL.
4994If @var{its_name} is specified, this name is used as string in import table.
4995Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4996are treated - beside @code{LIBRARY} - as simple name-identifiers.
4997If you want to use LIBRARY as name then you need to quote it.
4998
4999@item @code{DESCRIPTION} @var{string}
5000Puts @var{string} into the output @file{.exp} file in the
5001@code{.rdata} section.
5002
5003@item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
5004@item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
5005Generates @code{--stack} or @code{--heap}
5006@var{number-reserve},@var{number-commit} in the output @code{.drectve}
5007section. The linker will see this and act upon it.
5008
5009@item @code{CODE} @var{attr} @code{+}
5010@item @code{DATA} @var{attr} @code{+}
5011@item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
5012Generates @code{--attr} @var{section-name} @var{attr} in the output
5013@code{.drectve} section, where @var{attr} is one of @code{READ},
5014@code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
5015this and act upon it.
5016
5017@end table
5018
5019@ignore
5020@c man begin SEEALSO dlltool
5021The Info pages for @file{binutils}.
5022@c man end
5023@end ignore
5024
5025@node readelf
5026@chapter readelf
5027
5028@cindex ELF file information
5029@kindex readelf
5030
5031@c man title readelf display information about ELF files
5032
5033@smallexample
5034@c man begin SYNOPSIS readelf
5035readelf [@option{-a}|@option{--all}]
5036 [@option{-h}|@option{--file-header}]
5037 [@option{-l}|@option{--program-headers}|@option{--segments}]
5038 [@option{-S}|@option{--section-headers}|@option{--sections}]
5039 [@option{-g}|@option{--section-groups}]
5040 [@option{-t}|@option{--section-details}]
5041 [@option{-e}|@option{--headers}]
5042 [@option{-s}|@option{--syms}|@option{--symbols}]
5043 [@option{--dyn-syms}|@option{--lto-syms}]
5044 [@option{--sym-base=[0|8|10|16]}]
5045 [@option{--demangle@var{=style}}|@option{--no-demangle}]
5046 [@option{--quiet}]
5047 [@option{--recurse-limit}|@option{--no-recurse-limit}]
5048 [@option{-U} @var{method}|@option{--unicode=}@var{method}]
5049 [@option{-X}|@option{--extra-sym-info}|@option{--no-extra-sym-info}]
5050 [@option{-n}|@option{--notes}]
5051 [@option{-r}|@option{--relocs}]
5052 [@option{-u}|@option{--unwind}]
5053 [@option{-d}|@option{--dynamic}]
5054 [@option{-V}|@option{--version-info}]
5055 [@option{-A}|@option{--arch-specific}]
5056 [@option{-D}|@option{--use-dynamic}]
5057 [@option{-L}|@option{--lint}|@option{--enable-checks}]
5058 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
5059 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
5060 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
5061 [@option{-j} <number or name>|@option{--display-section=}<number or name>]
5062 [@option{-z}|@option{--decompress}]
5063 [@option{-c}|@option{--archive-index}]
5064 [@option{-w[lLiaprmfFsoORtUuTgAck]}|
5065 @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]]
5066 [@option{-wK}|@option{--debug-dump=follow-links}]
5067 [@option{-wN}|@option{--debug-dump=no-follow-links}]
5068 [@option{-wD}|@option{--debug-dump=use-debuginfod}]
5069 [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
5070 [@option{-P}|@option{--process-links}]
5071 [@option{--dwarf-depth=@var{n}}]
5072 [@option{--dwarf-start=@var{n}}]
5073 [@option{--ctf=}@var{section}]
5074 [@option{--ctf-parent=}@var{section}]
5075 [@option{--ctf-symbols=}@var{section}]
5076 [@option{--ctf-strings=}@var{section}]
5077 [@option{--sframe=}@var{section}]
5078 [@option{-I}|@option{--histogram}]
5079 [@option{-v}|@option{--version}]
5080 [@option{-W}|@option{--wide}]
5081 [@option{-T}|@option{--silent-truncation}]
5082 [@option{-H}|@option{--help}]
5083 @var{elffile}@dots{}
5084@c man end
5085@end smallexample
5086
5087@c man begin DESCRIPTION readelf
5088
5089@command{readelf} displays information about one or more ELF format object
5090files. The options control what particular information to display.
5091
5092@var{elffile}@dots{} are the object files to be examined. 32-bit and
509364-bit ELF files are supported, as are archives containing ELF files.
5094
5095This program performs a similar function to @command{objdump} but it
5096goes into more detail and it exists independently of the @sc{bfd}
5097library, so if there is a bug in @sc{bfd} then readelf will not be
5098affected.
5099
5100@c man end
5101
5102@c man begin OPTIONS readelf
5103
5104The long and short forms of options, shown here as alternatives, are
5105equivalent. At least one option besides @samp{-v} or @samp{-H} must be
5106given.
5107
5108@table @env
5109@item -a
5110@itemx --all
5111Equivalent to specifying @option{--file-header},
5112@option{--program-headers}, @option{--sections}, @option{--symbols},
5113@option{--relocs}, @option{--dynamic}, @option{--notes},
5114@option{--version-info}, @option{--arch-specific}, @option{--unwind},
5115@option{--section-groups} and @option{--histogram}.
5116
5117Note - this option does not enable @option{--use-dynamic} itself, so
5118if that option is not present on the command line then dynamic symbols
5119and dynamic relocs will not be displayed.
5120
5121@item -h
5122@itemx --file-header
5123@cindex ELF file header information
5124Displays the information contained in the ELF header at the start of the
5125file.
5126
5127@item -l
5128@itemx --program-headers
5129@itemx --segments
5130@cindex ELF program header information
5131@cindex ELF segment information
5132Displays the information contained in the file's segment headers, if it
5133has any.
5134
5135@item --quiet
5136@cindex quiet
5137Suppress "no symbols" diagnostic.
5138
5139@item -S
5140@itemx --sections
5141@itemx --section-headers
5142@cindex ELF section information
5143Displays the information contained in the file's section headers, if it
5144has any.
5145
5146@item -g
5147@itemx --section-groups
5148@cindex ELF section group information
5149Displays the information contained in the file's section groups, if it
5150has any.
5151
5152@item -t
5153@itemx --section-details
5154@cindex ELF section information
5155Displays the detailed section information. Implies @option{-S}.
5156
5157@item -s
5158@itemx --symbols
5159@itemx --syms
5160@cindex ELF symbol table information
5161Displays the entries in symbol table section of the file, if it has one.
5162If a symbol has version information associated with it then this is
5163displayed as well. The version string is displayed as a suffix to the
5164symbol name, preceded by an @@ character. For example
5165@samp{foo@@VER_1}. If the version is the default version to be used
5166when resolving unversioned references to the symbol then it is
5167displayed as a suffix preceded by two @@ characters. For example
5168@samp{foo@@@@VER_2}.
5169
5170@item --dyn-syms
5171@cindex ELF dynamic symbol table information
5172Displays the entries in dynamic symbol table section of the file, if it
5173has one. The output format is the same as the format used by the
5174@option{--syms} option.
5175
5176@item --lto-syms
5177@cindex LTO symbol table
5178Displays the contents of any LTO symbol tables in the file.
5179
5180@item --sym-base=[0|8|10|16]
5181@cindex symbol table size base
5182Forces the size field of the symbol table to use the given base. Any
5183unrecognized options will be treated as @samp{0}. @option{--sym-base=0}
5184represents the default and legacy behaviour. This will output sizes as decimal
5185for numbers less than 100000. For sizes 100000 and greater hexadecimal notation
5186will be used with a 0x prefix.
5187@option{--sym-base=8} will give the symbol sizes in octal.
5188@option{--sym-base=10} will always give the symbol sizes in decimal.
5189@option{--sym-base=16} will always give the symbol sizes in hexadecimal with a
51900x prefix.
5191
5192@item -C
5193@itemx --demangle[=@var{style}]
5194@cindex demangling in nm
5195Decode (@dfn{demangle}) low-level symbol names into user-level names.
5196This makes C++ function names readable. Different compilers have
5197different mangling styles. The optional demangling style argument can
5198be used to choose an appropriate demangling style for your
5199compiler. @xref{c++filt}, for more information on demangling.
5200
5201@item --no-demangle
5202Do not demangle low-level symbol names. This is the default.
5203
5204@item --recurse-limit
5205@itemx --no-recurse-limit
5206@itemx --recursion-limit
5207@itemx --no-recursion-limit
5208Enables or disables a limit on the amount of recursion performed
5209whilst demangling strings. Since the name mangling formats allow for
5210an infinite level of recursion it is possible to create strings whose
5211decoding will exhaust the amount of stack space available on the host
5212machine, triggering a memory fault. The limit tries to prevent this
5213from happening by restricting recursion to 2048 levels of nesting.
5214
5215The default is for this limit to be enabled, but disabling it may be
5216necessary in order to demangle truly complicated names. Note however
5217that if the recursion limit is disabled then stack exhaustion is
5218possible and any bug reports about such an event will be rejected.
5219
5220@item -U @var{[d|i|l|e|x|h]}
5221@itemx --unicode=[default|invalid|locale|escape|hex|highlight]
5222Controls the display of non-ASCII characters in identifier names.
5223The default (@option{--unicode=locale} or @option{--unicode=default}) is
5224to treat them as multibyte characters and display them in the current
5225locale. All other versions of this option treat the bytes as UTF-8
5226encoded values and attempt to interpret them. If they cannot be
5227interpreted or if the @option{--unicode=invalid} option is used then
5228they are displayed as a sequence of hex bytes, encloses in curly
5229parethesis characters.
5230
5231Using the @option{--unicode=escape} option will display the characters
5232as as unicode escape sequences (@var{\uxxxx}). Using the
5233@option{--unicode=hex} will display the characters as hex byte
5234sequences enclosed between angle brackets.
5235
5236Using the @option{--unicode=highlight} will display the characters as
5237unicode escape sequences but it will also highlighted them in red,
5238assuming that colouring is supported by the output device. The
5239colouring is intended to draw attention to the presence of unicode
5240sequences when they might not be expected.
5241
5242@item -X
5243@itemx --extra-sym-info
5244When displaying details of symbols, include extra information not
5245normally presented. Currently this just adds the name of the section
5246referenced by the symbol's index field, if there is one. In the
5247future more information may be displayed when this option is enabled.
5248
5249Enabling this option effectively enables the @option{--wide} option as
5250well, at least when displaying symbol information.
5251
5252@item --no-extra-sym-info
5253Disables the effect of the @option{--extra-sym-info} option. This
5254is the default.
5255
5256@item -e
5257@itemx --headers
5258Display all the headers in the file. Equivalent to @option{-h -l -S}.
5259
5260@item -n
5261@itemx --notes
5262@cindex ELF notes
5263Displays the contents of the NOTE segments and/or sections, if any.
5264
5265@item -r
5266@itemx --relocs
5267@cindex ELF reloc information
5268Displays the contents of the file's relocation section, if it has one.
5269
5270@item -u
5271@itemx --unwind
5272@cindex unwind information
5273Displays the contents of the file's unwind section, if it has one. Only
5274the unwind sections for IA64 ELF files, as well as ARM unwind tables
5275(@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
5276support is not yet implemented for your architecture you could try
5277dumping the contents of the @var{.eh_frames} section using the
5278@option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
5279options.
5280
5281@item -d
5282@itemx --dynamic
5283@cindex ELF dynamic section information
5284Displays the contents of the file's dynamic section, if it has one.
5285
5286@item -V
5287@itemx --version-info
5288@cindex ELF version sections information
5289Displays the contents of the version sections in the file, it they
5290exist.
5291
5292@item -A
5293@itemx --arch-specific
5294Displays architecture-specific information in the file, if there
5295is any.
5296
5297@item -D
5298@itemx --use-dynamic
5299When displaying symbols, this option makes @command{readelf} use the
5300symbol hash tables in the file's dynamic section, rather than the
5301symbol table sections.
5302
5303When displaying relocations, this option makes @command{readelf}
5304display the dynamic relocations rather than the static relocations.
5305
5306@item -L
5307@itemx --lint
5308@itemx --enable-checks
5309Displays warning messages about possible problems with the file(s)
5310being examined. If used on its own then all of the contents of the
5311file(s) will be examined. If used with one of the dumping options
5312then the warning messages will only be produced for the things being
5313displayed.
5314
5315@item -x <number or name>
5316@itemx --hex-dump=<number or name>
5317Displays the contents of the indicated section as a hexadecimal bytes.
5318A number identifies a particular section by index in the section table;
5319any other string identifies all sections with that name in the object file.
5320This option can be repeated multiple times on the command line in
5321order to request multiple hex dumps.
5322
5323@item -R <number or name>
5324@itemx --relocated-dump=<number or name>
5325Displays the contents of the indicated section as a hexadecimal
5326bytes. A number identifies a particular section by index in the
5327section table; any other string identifies all sections with that name
5328in the object file. The contents of the section will be relocated
5329before they are displayed.
5330This option can be repeated multiple times on the command line in
5331order to request multiple relocated dumps.
5332
5333@item -p <number or name>
5334@itemx --string-dump=<number or name>
5335Displays the contents of the indicated section as printable strings.
5336A number identifies a particular section by index in the section table;
5337any other string identifies all sections with that name in the object file.
5338This option can be repeated multiple times on the command line in
5339order to request multiple string dumps.
5340
5341@item -j <number or name>
5342@itemx --display-section
5343Displays the contents of the indicated section according to its
5344section header type. Sections containing relocations will be
5345displayed as if the @option{--relocations} option had been used,
5346sections contains symbols will be displayed as if the @option{--syms}
5347option had been used and so on.
5348
5349A number identifies a particular section by index in the section
5350table; any other string identifies all sections with that name in the
5351input file(s).
5352
5353This option can be repeated multiple times on the command line in
5354order to request multiple section dumps.
5355
5356@item -z
5357@itemx --decompress
5358Requests that the section(s) being dumped by @option{x}, @option{R} or
5359@option{p} options are decompressed before being displayed. If the
5360section(s) are not compressed then they are displayed as is.
5361
5362@item -c
5363@itemx --archive-index
5364@cindex Archive file symbol index information
5365Displays the file symbol index information contained in the header part
5366of binary archives. Performs the same function as the @option{t}
5367command to @command{ar}, but without using the BFD library. @xref{ar}.
5368
5369@item -w[lLiaprmfFsOoRtUuTgAckK]
5370@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]
5371@include debug.options.texi
5372
5373@item -P
5374@itemx --process-links
5375Display the contents of non-debug sections found in separate debuginfo
5376files that are linked to the main file. This option automatically
5377implies the @option{-wK} option, and only sections requested by other
5378command line options will be displayed.
5379
5380@include ctf.options.texi
5381@item --ctf-symbols=@var{section}
5382@item --ctf-strings=@var{section}
5383Specify the name of another section from which the CTF file can inherit
5384strings and symbols. By default, the @code{.symtab} and its linked
5385string table are used.
5386
5387If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
5388other must be specified as well.
5389
5390@item -I
5391@itemx --histogram
5392Display a histogram of bucket list lengths when displaying the contents
5393of the symbol tables.
5394
5395@item -v
5396@itemx --version
5397Display the version number of readelf.
5398
5399@item -W
5400@itemx --wide
5401Don't break output lines to fit into 80 columns. By default
5402@command{readelf} breaks section header and segment listing lines for
540364-bit ELF files, so that they fit into 80 columns. This option causes
5404@command{readelf} to print each section header resp. each segment one a
5405single line, which is far more readable on terminals wider than 80 columns.
5406
5407@item -T
5408@itemx --silent-truncation
5409Normally when readelf is displaying a symbol name, and it has to
5410truncate the name to fit into an 80 column display, it will add a
5411suffix of @code{[...]} to the name. This command line option
5412disables this behaviour, allowing 5 more characters of the name to be
5413displayed and restoring the old behaviour of readelf (prior to release
54142.35).
5415
5416@item -H
5417@itemx --help
5418Display the command-line options understood by @command{readelf}.
5419
5420@end table
5421
5422@c man end
5423
5424@ignore
5425@c man begin SEEALSO readelf
5426objdump(1), and the Info entries for @file{binutils}.
5427@c man end
5428@end ignore
5429
5430@node elfedit
5431@chapter elfedit
5432
5433@cindex Update ELF header
5434@kindex elfedit
5435
5436@c man title elfedit update ELF header and program property of ELF files
5437
5438@smallexample
5439@c man begin SYNOPSIS elfedit
5440elfedit [@option{--input-mach=}@var{machine}]
5441 [@option{--input-type=}@var{type}]
5442 [@option{--input-osabi=}@var{osabi}]
5443 [@option{--input-abiversion=}@var{version}]
5444 @option{--output-mach=}@var{machine}
5445 @option{--output-type=}@var{type}
5446 @option{--output-osabi=}@var{osabi}
5447 @option{--output-abiversion=}@var{version}
5448 @option{--enable-x86-feature=}@var{feature}
5449 @option{--disable-x86-feature=}@var{feature}
5450 [@option{-v}|@option{--version}]
5451 [@option{-h}|@option{--help}]
5452 @var{elffile}@dots{}
5453@c man end
5454@end smallexample
5455
5456@c man begin DESCRIPTION elfedit
5457
5458@command{elfedit} updates the ELF header and program property of ELF
5459files which have the matching ELF machine and file types. The options
5460control how and which fields in the ELF header and program property
5461should be updated.
5462
5463@var{elffile}@dots{} are the ELF files to be updated. 32-bit and
546464-bit ELF files are supported, as are archives containing ELF files.
5465@c man end
5466
5467@c man begin OPTIONS elfedit
5468
5469The long and short forms of options, shown here as alternatives, are
5470equivalent. At least one of the @option{--output-mach},
5471@option{--output-type}, @option{--output-osabi},
5472@option{--output-abiversion},
5473@option{--enable-x86-feature} and @option{--disable-x86-feature}
5474options must be given.
5475
5476@table @env
5477
5478@item --input-mach=@var{machine}
5479Set the matching input ELF machine type to @var{machine}. If
5480@option{--input-mach} isn't specified, it will match any ELF
5481machine types.
5482
5483The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5484@var{K1OM} and @var{x86-64}.
5485
5486@item --output-mach=@var{machine}
5487Change the ELF machine type in the ELF header to @var{machine}. The
5488supported ELF machine types are the same as @option{--input-mach}.
5489
5490@item --input-type=@var{type}
5491Set the matching input ELF file type to @var{type}. If
5492@option{--input-type} isn't specified, it will match any ELF file types.
5493
5494The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5495
5496@item --output-type=@var{type}
5497Change the ELF file type in the ELF header to @var{type}. The
5498supported ELF types are the same as @option{--input-type}.
5499
5500@item --input-osabi=@var{osabi}
5501Set the matching input ELF file OSABI to @var{osabi}. If
5502@option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5503
5504The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5505@var{GNU}, @var{Linux} (alias for @var{GNU}),
5506@var{Solaris}, @var{AIX}, @var{Irix},
5507@var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5508@var{NSK}, @var{AROS} and @var{FenixOS}.
5509
5510@item --output-osabi=@var{osabi}
5511Change the ELF OSABI in the ELF header to @var{osabi}. The
5512supported ELF OSABI are the same as @option{--input-osabi}.
5513
5514@item --input-abiversion=@var{version}
5515Set the matching input ELF file ABIVERSION to @var{version}.
5516@var{version} must be between 0 and 255. If @option{--input-abiversion}
5517isn't specified, it will match any ELF ABIVERSIONs.
5518
5519@item --output-abiversion=@var{version}
5520Change the ELF ABIVERSION in the ELF header to @var{version}.
5521@var{version} must be between 0 and 255.
5522
5523@item --enable-x86-feature=@var{feature}
5524Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5525ELF files with machine types of @var{i386} or @var{x86-64}. The
5526supported features are, @var{ibt}, @var{shstk}, @var{lam_u48} and
5527@var{lam_u57}.
5528
5529@item --disable-x86-feature=@var{feature}
5530Clear the @var{feature} bit in program property in @var{exec} or
5531@var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5532The supported features are the same as @option{--enable-x86-feature}.
5533
5534Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5535are available only on hosts with @samp{mmap} support.
5536
5537@item -v
5538@itemx --version
5539Display the version number of @command{elfedit}.
5540
5541@item -h
5542@itemx --help
5543Display the command-line options understood by @command{elfedit}.
5544
5545@end table
5546
5547@c man end
5548
5549@ignore
5550@c man begin SEEALSO elfedit
5551readelf(1), and the Info entries for @file{binutils}.
5552@c man end
5553@end ignore
5554
5555@node Common Options
5556@chapter Common Options
5557
5558The following command-line options are supported by all of the
5559programs described in this manual.
5560
5561@c man begin OPTIONS
5562@table @env
5563@include at-file.texi
5564@c man end
5565
5566@item --help
5567Display the command-line options supported by the program.
5568
5569@item --version
5570Display the version number of the program.
5571
5572@c man begin OPTIONS
5573@end table
5574@c man end
5575
5576@node Selecting the Target System
5577@chapter Selecting the Target System
5578
5579You can specify two aspects of the target system to the @sc{gnu}
5580binary file utilities, each in several ways:
5581
5582@itemize @bullet
5583@item
5584the target
5585
5586@item
5587the architecture
5588@end itemize
5589
5590In the following summaries, the lists of ways to specify values are in
5591order of decreasing precedence. The ways listed first override those
5592listed later.
5593
5594The commands to list valid values only list the values for which the
5595programs you are running were configured. If they were configured with
5596@option{--enable-targets=all}, the commands list most of the available
5597values, but a few are left out; not all targets can be configured in at
5598once because some of them can only be configured @dfn{native} (on hosts
5599with the same type as the target system).
5600
5601@menu
5602* Target Selection::
5603* Architecture Selection::
5604@end menu
5605
5606@node Target Selection
5607@section Target Selection
5608
5609A @dfn{target} is an object file format. A given target may be
5610supported for multiple architectures (@pxref{Architecture Selection}).
5611A target selection may also have variations for different operating
5612systems or architectures.
5613
5614The command to list valid target values is @samp{objdump -i}
5615(the first column of output contains the relevant information).
5616
5617Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5618@samp{a.out-sunos-big}.
5619
5620You can also specify a target using a configuration triplet. This is
5621the same sort of name that is passed to @file{configure} to specify a
5622target. When you use a configuration triplet as an argument, it must be
5623fully canonicalized. You can see the canonical version of a triplet by
5624running the shell script @file{config.sub} which is included with the
5625sources.
5626
5627Some sample configuration triplets are: @samp{m68k-hp-bsd},
5628@samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5629
5630@subheading @command{objdump} Target
5631
5632Ways to specify:
5633
5634@enumerate
5635@item
5636command-line option: @option{-b} or @option{--target}
5637
5638@item
5639environment variable @code{GNUTARGET}
5640
5641@item
5642deduced from the input file
5643@end enumerate
5644
5645@subheading @command{objcopy} and @command{strip} Input Target
5646
5647Ways to specify:
5648
5649@enumerate
5650@item
5651command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5652
5653@item
5654environment variable @code{GNUTARGET}
5655
5656@item
5657deduced from the input file
5658@end enumerate
5659
5660@subheading @command{objcopy} and @command{strip} Output Target
5661
5662Ways to specify:
5663
5664@enumerate
5665@item
5666command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5667
5668@item
5669the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5670
5671@item
5672environment variable @code{GNUTARGET}
5673
5674@item
5675deduced from the input file
5676@end enumerate
5677
5678@subheading @command{nm}, @command{size}, and @command{strings} Target
5679
5680Ways to specify:
5681
5682@enumerate
5683@item
5684command-line option: @option{--target}
5685
5686@item
5687environment variable @code{GNUTARGET}
5688
5689@item
5690deduced from the input file
5691@end enumerate
5692
5693@node Architecture Selection
5694@section Architecture Selection
5695
5696An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5697to run. Its name may contain a colon, separating the name of the
5698processor family from the name of the particular @sc{cpu}.
5699
5700The command to list valid architecture values is @samp{objdump -i} (the
5701second column contains the relevant information).
5702
5703Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5704
5705@subheading @command{objdump} Architecture
5706
5707Ways to specify:
5708
5709@enumerate
5710@item
5711command-line option: @option{-m} or @option{--architecture}
5712
5713@item
5714deduced from the input file
5715@end enumerate
5716
5717@subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5718
5719Ways to specify:
5720
5721@enumerate
5722@item
5723deduced from the input file
5724@end enumerate
5725
5726@node debuginfod
5727@chapter debuginfod
5728@cindex separate debug files
5729
5730debuginfod is a web service that indexes ELF/DWARF debugging resources
5731by build-id and serves them over HTTP. For more information see:
5732@emph{https://sourceware.org/elfutils/Debuginfod.html}
5733
5734Binutils can be built with the debuginfod client library
5735@code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5736This option is enabled by default if @code{libdebuginfod} is installed
5737and found at configure time. This allows @command{objdump} and
5738@command{readelf} to automatically query debuginfod servers for
5739separate debug files when the files are otherwise not found.
5740
5741debuginfod is packaged with elfutils, starting with version 0.178.
5742You can get the latest version from `https://sourceware.org/elfutils/'.
5743
5744The DWARF info dumping tools (@command{readelf} and @command{objdump})
5745have options to control when they should access the debuginfod
5746servers. By default this access is enabled.
5747
5748@node Reporting Bugs
5749@chapter Reporting Bugs
5750@cindex bugs
5751@cindex reporting bugs
5752
5753Your bug reports play an essential role in making the binary utilities
5754reliable.
5755
5756Reporting a bug may help you by bringing a solution to your problem, or
5757it may not. But in any case the principal function of a bug report is
5758to help the entire community by making the next version of the binary
5759utilities work better. Bug reports are your contribution to their
5760maintenance.
5761
5762In order for a bug report to serve its purpose, you must include the
5763information that enables us to fix the bug.
5764
5765@menu
5766* Bug Criteria:: Have you found a bug?
5767* Bug Reporting:: How to report bugs
5768@end menu
5769
5770@node Bug Criteria
5771@section Have You Found a Bug?
5772@cindex bug criteria
5773
5774If you are not sure whether you have found a bug, here are some guidelines:
5775
5776@itemize @bullet
5777@cindex fatal signal
5778@cindex crash
5779@item
5780If a binary utility gets a fatal signal, for any input whatever, that is
5781a bug. Reliable utilities never crash.
5782
5783@cindex error on valid input
5784@item
5785If a binary utility produces an error message for valid input, that is a
5786bug.
5787
5788@item
5789If you are an experienced user of binary utilities, your suggestions for
5790improvement are welcome in any case.
5791@end itemize
5792
5793@node Bug Reporting
5794@section How to Report Bugs
5795@cindex bug reports
5796@cindex bugs, reporting
5797
5798A number of companies and individuals offer support for @sc{gnu}
5799products. If you obtained the binary utilities from a support
5800organization, we recommend you contact that organization first.
5801
5802You can find contact information for many support companies and
5803individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5804distribution.
5805
5806@ifset BUGURL
5807In any event, we also recommend that you send bug reports for the binary
5808utilities to @value{BUGURL}.
5809@end ifset
5810
5811The fundamental principle of reporting bugs usefully is this:
5812@strong{report all the facts}. If you are not sure whether to state a
5813fact or leave it out, state it!
5814
5815Often people omit facts because they think they know what causes the
5816problem and assume that some details do not matter. Thus, you might
5817assume that the name of a file you use in an example does not matter.
5818Well, probably it does not, but one cannot be sure. Perhaps the bug is
5819a stray memory reference which happens to fetch from the location where
5820that pathname is stored in memory; perhaps, if the pathname were
5821different, the contents of that location would fool the utility into
5822doing the right thing despite the bug. Play it safe and give a
5823specific, complete example. That is the easiest thing for you to do,
5824and the most helpful.
5825
5826Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5827it is new to us. Therefore, always write your bug reports on the assumption
5828that the bug has not been reported previously.
5829
5830Sometimes people give a few sketchy facts and ask, ``Does this ring a
5831bell?'' This cannot help us fix a bug, so it is basically useless. We
5832respond by asking for enough details to enable us to investigate.
5833You might as well expedite matters by sending them to begin with.
5834
5835To enable us to fix the bug, you should include all these things:
5836
5837@itemize @bullet
5838@item
5839The version of the utility. Each utility announces it if you start it
5840with the @option{--version} argument.
5841
5842Without this, we will not know whether there is any point in looking for
5843the bug in the current version of the binary utilities.
5844
5845@item
5846Any patches you may have applied to the source, including any patches
5847made to the @code{BFD} library.
5848
5849@item
5850The type of machine you are using, and the operating system name and
5851version number.
5852
5853@item
5854What compiler (and its version) was used to compile the utilities---e.g.
5855``@code{gcc-2.7}''.
5856
5857@item
5858The command arguments you gave the utility to observe the bug. To
5859guarantee you will not omit something important, list them all. A copy
5860of the Makefile (or the output from make) is sufficient.
5861
5862If we were to try to guess the arguments, we would probably guess wrong
5863and then we might not encounter the bug.
5864
5865@item
5866A complete input file, or set of input files, that will reproduce the
5867bug. If the utility is reading an object file or files, then it is
5868generally most helpful to send the actual object files.
5869
5870If the source files were produced exclusively using @sc{gnu} programs
5871(e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5872may be OK to send the source files rather than the object files. In
5873this case, be sure to say exactly what version of @command{gcc}, or
5874whatever, was used to produce the object files. Also say how
5875@command{gcc}, or whatever, was configured.
5876
5877@item
5878A description of what behavior you observe that you believe is
5879incorrect. For example, ``It gets a fatal signal.''
5880
5881Of course, if the bug is that the utility gets a fatal signal, then we
5882will certainly notice it. But if the bug is incorrect output, we might
5883not notice unless it is glaringly wrong. You might as well not give us
5884a chance to make a mistake.
5885
5886Even if the problem you experience is a fatal signal, you should still
5887say so explicitly. Suppose something strange is going on, such as your
5888copy of the utility is out of sync, or you have encountered a bug in
5889the C library on your system. (This has happened!) Your copy might
5890crash and ours would not. If you told us to expect a crash, then when
5891ours fails to crash, we would know that the bug was not happening for
5892us. If you had not told us to expect a crash, then we would not be able
5893to draw any conclusion from our observations.
5894
5895@item
5896If you wish to suggest changes to the source, send us context diffs, as
5897generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5898option. Always send diffs from the old file to the new file. If you
5899wish to discuss something in the @command{ld} source, refer to it by
5900context, not by line number.
5901
5902The line numbers in our development sources will not match those in your
5903sources. Your line numbers would convey no useful information to us.
5904@end itemize
5905
5906Here are some things that are not necessary:
5907
5908@itemize @bullet
5909@item
5910A description of the envelope of the bug.
5911
5912Often people who encounter a bug spend a lot of time investigating
5913which changes to the input file will make the bug go away and which
5914changes will not affect it.
5915
5916This is often time consuming and not very useful, because the way we
5917will find the bug is by running a single example under the debugger
5918with breakpoints, not by pure deduction from a series of examples.
5919We recommend that you save your time for something else.
5920
5921Of course, if you can find a simpler example to report @emph{instead}
5922of the original one, that is a convenience for us. Errors in the
5923output will be easier to spot, running under the debugger will take
5924less time, and so on.
5925
5926However, simplification is not vital; if you do not want to do this,
5927report the bug anyway and send us the entire test case you used.
5928
5929@item
5930A patch for the bug.
5931
5932A patch for the bug does help us if it is a good one. But do not omit
5933the necessary information, such as the test case, on the assumption that
5934a patch is all we need. We might see problems with your patch and decide
5935to fix the problem another way, or we might not understand it at all.
5936
5937Sometimes with programs as complicated as the binary utilities it is
5938very hard to construct an example that will make the program follow a
5939certain path through the code. If you do not send us the example, we
5940will not be able to construct one, so we will not be able to verify that
5941the bug is fixed.
5942
5943And if we cannot understand what bug you are trying to fix, or why your
5944patch should be an improvement, we will not install it. A test case will
5945help us to understand.
5946
5947@item
5948A guess about what the bug is or what it depends on.
5949
5950Such guesses are usually wrong. Even we cannot guess right about such
5951things without first using the debugger to find the facts.
5952@end itemize
5953
5954@node GNU Free Documentation License
5955@appendix GNU Free Documentation License
5956
5957@include fdl.texi
5958
5959@node Binutils Index
5960@unnumbered Binutils Index
5961
5962@printindex cp
5963
5964@bye