f94693631c70e606dee379d2e9cd732e0a9def9f
[binutils-gdb.git] / binutils / doc / binutils.texi
1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
4 @finalout
5 @synindex ky cp
6
7 @c man begin INCLUDE
8 @include bfdver.texi
9 @c man end
10
11 @copying
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2023 Free Software Foundation, Inc.
14
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
21
22 @c man end
23 @end copying
24
25 @dircategory Software development
26 @direntry
27 * Binutils: (binutils). The GNU binary utilities.
28 @end direntry
29
30 @dircategory Individual utilities
31 @direntry
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nm: (binutils)nm. List symbols from object files.
38 * objcopy: (binutils)objcopy. Copy and translate object files.
39 * objdump: (binutils)objdump. Display information from object files.
40 * ranlib: (binutils)ranlib. Generate index to archive contents.
41 * readelf: (binutils)readelf. Display the contents of ELF format files.
42 * size: (binutils)size. List section sizes and total size.
43 * strings: (binutils)strings. List printable strings from files.
44 * strip: (binutils)strip. Discard symbols.
45 * elfedit: (binutils)elfedit. Update ELF header and property of ELF files.
46 * windmc: (binutils)windmc. Generator for Windows message resources.
47 * windres: (binutils)windres. Manipulate Windows resources.
48 @end direntry
49
50 @titlepage
51 @title The @sc{gnu} Binary Utilities
52 @ifset VERSION_PACKAGE
53 @subtitle @value{VERSION_PACKAGE}
54 @end ifset
55 @subtitle Version @value{VERSION}
56 @sp 1
57 @subtitle @value{UPDATED}
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
61 @page
62
63 @tex
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 Texinfo \texinfoversion\par }
66 @end tex
67
68 @vskip 0pt plus 1filll
69 @insertcopying
70 @end titlepage
71 @contents
72
73 @node Top
74 @top Introduction
75
76 @cindex version
77 This brief manual contains documentation for the @sc{gnu} binary
78 utilities
79 @ifset VERSION_PACKAGE
80 @value{VERSION_PACKAGE}
81 @end ifset
82 version @value{VERSION}:
83
84 @iftex
85 @table @code
86 @item ar
87 Create, modify, and extract from archives
88
89 @item nm
90 List symbols from object files
91
92 @item objcopy
93 Copy and translate object files
94
95 @item objdump
96 Display information from object files
97
98 @item ranlib
99 Generate index to archive contents
100
101 @item readelf
102 Display the contents of ELF format files.
103
104 @item size
105 List file section sizes and total size
106
107 @item strings
108 List printable strings from files
109
110 @item strip
111 Discard symbols
112
113 @item elfedit
114 Update the ELF header and program property of ELF files.
115
116 @item c++filt
117 Demangle encoded C++ symbols (on MS-DOS, this program is named
118 @code{cxxfilt})
119
120 @item addr2line
121 Convert addresses or symbol+offset into file names and line numbers
122
123 @item windres
124 Manipulate Windows resources
125
126 @item windmc
127 Generator for Windows message resources
128
129 @item dlltool
130 Create the files needed to build and use Dynamic Link Libraries
131 @end table
132 @end iftex
133
134 This document is distributed under the terms of the GNU Free
135 Documentation License version 1.3. A copy of the license is included
136 in the section entitled ``GNU Free Documentation License''.
137
138 @menu
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * size:: List section sizes and total size
145 * strings:: List printable strings from files
146 * strip:: Discard symbols
147 * c++filt:: Filter to demangle encoded C++ symbols
148 * cxxfilt: c++filt. MS-DOS name for c++filt
149 * addr2line:: Convert addresses or symbol+offset to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update ELF header and property of ELF files
155 * Common Options:: Command-line options for all utilities
156 * Selecting the Target System:: How these utilities determine the target
157 * debuginfod:: Using binutils with debuginfod
158 * Reporting Bugs:: Reporting Bugs
159 * GNU Free Documentation License:: GNU Free Documentation License
160 * Binutils Index:: Binutils Index
161 @end menu
162
163 @node ar
164 @chapter ar
165
166 @kindex ar
167 @cindex archives
168 @cindex collections of files
169
170 @c man title ar create, modify, and extract from archives
171
172 @smallexample
173 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
174 ar -M [ <mri-script ]
175 @end smallexample
176
177 @c man begin DESCRIPTION ar
178
179 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
180 archives. An @dfn{archive} is a single file holding a collection of
181 other files in a structure that makes it possible to retrieve
182 the original individual files (called @dfn{members} of the archive).
183
184 The original files' contents, mode (permissions), timestamp, owner, and
185 group are preserved in the archive, and can be restored on
186 extraction.
187
188 @cindex name length
189 @sc{gnu} @command{ar} can maintain archives whose members have names of any
190 length; however, depending on how @command{ar} is configured on your
191 system, a limit on member-name length may be imposed for compatibility
192 with archive formats maintained with other tools. If it exists, the
193 limit is often 15 characters (typical of formats related to a.out) or 16
194 characters (typical of formats related to coff).
195
196 @cindex libraries
197 @command{ar} is considered a binary utility because archives of this sort
198 are most often used as @dfn{libraries} holding commonly needed
199 subroutines. Since libraries often will depend on other libraries,
200 @command{ar} can also record the dependencies of a library when the
201 @option{--record-libdeps} option is specified.
202
203 @cindex symbol index
204 @command{ar} creates an index to the symbols defined in relocatable
205 object modules in the archive when you specify the modifier @samp{s}.
206 Once created, this index is updated in the archive whenever @command{ar}
207 makes a change to its contents (save for the @samp{q} update operation).
208 An archive with such an index speeds up linking to the library, and
209 allows routines in the library to call each other without regard to
210 their placement in the archive.
211
212 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
213 table. If an archive lacks the table, another form of @command{ar} called
214 @command{ranlib} can be used to add just the table.
215
216 @cindex thin archives
217 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
218 which contains a symbol index and references to the original copies
219 of the member files of the archive. This is useful for building
220 libraries for use within a local build tree, where the relocatable
221 objects are expected to remain available, and copying the contents of
222 each object would only waste time and space.
223
224 An archive can either be @emph{thin} or it can be normal. It cannot
225 be both at the same time. Once an archive is created its format
226 cannot be changed without first deleting it and then creating a new
227 archive in its place.
228
229 Thin archives are also @emph{flattened}, so that adding one thin
230 archive to another thin archive does not nest it, as would happen with
231 a normal archive. Instead the elements of the first archive are added
232 individually to the second archive.
233
234 The paths to the elements of the archive are stored relative to the
235 archive itself.
236
237 @cindex compatibility, @command{ar}
238 @cindex @command{ar} compatibility
239 @sc{gnu} @command{ar} is designed to be compatible with two different
240 facilities. You can control its activity using command-line options,
241 like the different varieties of @command{ar} on Unix systems; or, if you
242 specify the single command-line option @option{-M}, you can control it
243 with a script supplied via standard input, like the MRI ``librarian''
244 program.
245
246 @c man end
247
248 @menu
249 * ar cmdline:: Controlling @command{ar} on the command line
250 * ar scripts:: Controlling @command{ar} with a script
251 @end menu
252
253 @page
254 @node ar cmdline
255 @section Controlling @command{ar} on the Command Line
256
257 @smallexample
258 @c man begin SYNOPSIS ar
259 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@option{--thin}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
260 @c man end
261 @end smallexample
262
263 @cindex Unix compatibility, @command{ar}
264 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
265 arguments to execute: one keyletter specifying the @emph{operation}
266 (optionally accompanied by other keyletters specifying
267 @emph{modifiers}), and the archive name to act on.
268
269 Most operations can also accept further @var{member} arguments,
270 specifying particular files to operate on.
271
272 @c man begin OPTIONS ar
273
274 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
275 flags @var{mod} in any order, within the first command-line argument.
276
277 If you wish, you may begin the first command-line argument with a
278 dash.
279
280 @cindex operations on archive
281 The @var{p} keyletter specifies what operation to execute; it may be
282 any of the following, but you must specify only one of them:
283
284 @table @samp
285 @item d
286 @cindex deleting from archive
287 @emph{Delete} modules from the archive. Specify the names of modules to
288 be deleted as @var{member}@dots{}; the archive is untouched if you
289 specify no files to delete.
290
291 If you specify the @samp{v} modifier, @command{ar} lists each module
292 as it is deleted.
293
294 @item m
295 @cindex moving in archive
296 Use this operation to @emph{move} members in an archive.
297
298 The ordering of members in an archive can make a difference in how
299 programs are linked using the library, if a symbol is defined in more
300 than one member.
301
302 If no modifiers are used with @code{m}, any members you name in the
303 @var{member} arguments are moved to the @emph{end} of the archive;
304 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
305 specified place instead.
306
307 @item p
308 @cindex printing from archive
309 @emph{Print} the specified members of the archive, to the standard
310 output file. If the @samp{v} modifier is specified, show the member
311 name before copying its contents to standard output.
312
313 If you specify no @var{member} arguments, all the files in the archive are
314 printed.
315
316 @item q
317 @cindex quick append to archive
318 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
319 @var{archive}, without checking for replacement.
320
321 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
322 operation; new members are always placed at the end of the archive.
323
324 The modifier @samp{v} makes @command{ar} list each file as it is appended.
325
326 Since the point of this operation is speed, implementations of
327 @command{ar} have the option of not updating the archive's symbol
328 table if one exists. Too many different systems however assume that
329 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
330 rebuild the table even with a quick append.
331
332 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
333 synonym for @samp{r} - replacing already existing files in the
334 archive and appending new ones at the end.
335
336 @item r
337 @cindex replacement in archive
338 Insert the files @var{member}@dots{} into @var{archive} (with
339 @emph{replacement}). This operation differs from @samp{q} in that any
340 previously existing members are deleted if their names match those being
341 added.
342
343 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
344 displays an error message, and leaves undisturbed any existing members
345 of the archive matching that name.
346
347 By default, new members are added at the end of the file; but you may
348 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
349 placement relative to some existing member.
350
351 The modifier @samp{v} used with this operation elicits a line of
352 output for each file inserted, along with one of the letters @samp{a} or
353 @samp{r} to indicate whether the file was appended (no old member
354 deleted) or replaced.
355
356 @item s
357 @cindex ranlib
358 Add an index to the archive, or update it if it already exists. Note
359 this command is an exception to the rule that there can only be one
360 command letter, as it is possible to use it as either a command or a
361 modifier. In either case it does the same thing.
362
363 @item t
364 @cindex contents of archive
365 Display a @emph{table} listing the contents of @var{archive}, or those
366 of the files listed in @var{member}@dots{} that are present in the
367 archive. Normally only the member name is shown, but if the modifier
368 @samp{O} is specified, then the corresponding offset of the member is also
369 displayed. Finally, in order to see the modes (permissions), timestamp,
370 owner, group, and size the @samp{v} modifier should be included.
371
372 If you do not specify a @var{member}, all files in the archive
373 are listed.
374
375 @cindex repeated names in archive
376 @cindex name duplication in archive
377 If there is more than one file with the same name (say, @samp{fie}) in
378 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
379 first instance; to see them all, you must ask for a complete
380 listing---in our example, @samp{ar t b.a}.
381 @c WRS only; per Gumby, this is implementation-dependent, and in a more
382 @c recent case in fact works the other way.
383
384 @item x
385 @cindex extract from archive
386 @emph{Extract} members (named @var{member}) from the archive. You can
387 use the @samp{v} modifier with this operation, to request that
388 @command{ar} list each name as it extracts it.
389
390 If you do not specify a @var{member}, all files in the archive
391 are extracted.
392
393 Files cannot be extracted from a thin archive, and there are
394 restrictions on extracting from archives created with @option{P}: The
395 paths must not be absolute, may not contain @code{..}, and any
396 subdirectories in the paths must exist. If it is desired to avoid
397 these restrictions then used the @option{--output} option to specify
398 an output directory.
399 @end table
400
401 A number of modifiers (@var{mod}) may immediately follow the @var{p}
402 keyletter, to specify variations on an operation's behavior:
403
404 @table @samp
405 @item a
406 @cindex relative placement in archive
407 Add new files @emph{after} an existing member of the
408 archive. If you use the modifier @samp{a}, the name of an existing archive
409 member must be present as the @var{relpos} argument, before the
410 @var{archive} specification.
411
412 @item b
413 Add new files @emph{before} an existing member of the
414 archive. If you use the modifier @samp{b}, the name of an existing archive
415 member must be present as the @var{relpos} argument, before the
416 @var{archive} specification. (same as @samp{i}).
417
418 @item c
419 @cindex creating archives
420 @emph{Create} the archive. The specified @var{archive} is always
421 created if it did not exist, when you request an update. But a warning is
422 issued unless you specify in advance that you expect to create it, by
423 using this modifier.
424
425 @item D
426 @cindex deterministic archives
427 @kindex --enable-deterministic-archives
428 Operate in @emph{deterministic} mode. When adding files and the archive
429 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
430 for all files. When this option is used, if @command{ar} is used with
431 identical options and identical input files, multiple runs will create
432 identical output files regardless of the input files' owners, groups,
433 file modes, or modification times.
434
435 If @file{binutils} was configured with
436 @option{--enable-deterministic-archives}, then this mode is on by default.
437 It can be disabled with the @samp{U} modifier, below.
438
439 @item f
440 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
441 names of any length. This will cause it to create archives which are
442 not compatible with the native @command{ar} program on some systems. If
443 this is a concern, the @samp{f} modifier may be used to truncate file
444 names when putting them in the archive.
445
446 @item i
447 Insert new files @emph{before} an existing member of the
448 archive. If you use the modifier @samp{i}, the name of an existing archive
449 member must be present as the @var{relpos} argument, before the
450 @var{archive} specification. (same as @samp{b}).
451
452 @item l
453 @c This modifier was accepted but not used.
454 @c whaffor ar l modifier??? presumably compat; with
455 @c what???---doc@@cygnus.com, 25jan91
456 Specify dependencies of this library. The dependencies must immediately
457 follow this option character, must use the same syntax as the linker
458 command line, and must be specified within a single argument. I.e., if
459 multiple items are needed, they must be quoted to form a single command
460 line argument. For example @samp{L "-L/usr/local/lib -lmydep1 -lmydep2"}
461
462 @item N
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
466
467 @item o
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
472
473 @item O
474 @cindex offsets of files
475 Display member offsets inside the archive. Use together with the @samp{t}
476 option.
477
478 @item P
479 Use the full path name when matching or storing names in the archive.
480 Archives created with full path names are not POSIX compliant, and
481 thus may not work with tools other than up to date @sc{gnu} tools.
482 Modifying such archives with @sc{gnu} @command{ar} without using
483 @option{P} will remove the full path names unless the archive is a
484 thin archive. Note that @option{P} may be useful when adding files to
485 a thin archive since @option{r} without @option{P} ignores the path
486 when choosing which element to replace. Thus
487 @smallexample
488 ar rcST archive.a subdir/file1 subdir/file2 file1
489 @end smallexample
490 will result in the first @code{subdir/file1} being replaced with
491 @code{file1} from the current directory. Adding @option{P} will
492 prevent this replacement.
493
494 @item s
495 @cindex writing archive index
496 Write an object-file index into the archive, or update an existing one,
497 even if no other change is made to the archive. You may use this modifier
498 flag either with any operation, or alone. Running @samp{ar s} on an
499 archive is equivalent to running @samp{ranlib} on it.
500
501 @item S
502 @cindex not writing archive index
503 Do not generate an archive symbol table. This can speed up building a
504 large library in several steps. The resulting archive can not be used
505 with the linker. In order to build a symbol table, you must omit the
506 @samp{S} modifier on the last execution of @samp{ar}, or you must run
507 @samp{ranlib} on the archive.
508
509 @item T
510 Deprecated alias for @option{--thin}. @option{T} is not recommended because in
511 many ar implementations @option{T} has a different meaning, as specified by
512 X/Open System Interface.
513
514 @item u
515 @cindex updating an archive
516 Normally, @samp{ar r}@dots{} inserts all files
517 listed into the archive. If you would like to insert @emph{only} those
518 of the files you list that are newer than existing members of the same
519 names, use this modifier. The @samp{u} modifier is allowed only for the
520 operation @samp{r} (replace). In particular, the combination @samp{qu} is
521 not allowed, since checking the timestamps would lose any speed
522 advantage from the operation @samp{q}.
523
524 Note - if an archive has been created in a deterministic manner, eg
525 via the use of the @option{D} modifier, then replacement will always
526 happen and the @option{u} modifier will be ineffective.
527
528 @item U
529 @cindex deterministic archives
530 @kindex --enable-deterministic-archives
531 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
532 of the @samp{D} modifier, above: added files and the archive index will
533 get their actual UID, GID, timestamp, and file mode values.
534
535 This is the default unless @file{binutils} was configured with
536 @option{--enable-deterministic-archives}.
537
538 @item v
539 This modifier requests the @emph{verbose} version of an operation. Many
540 operations display additional information, such as filenames processed,
541 when the modifier @samp{v} is appended.
542
543 @item V
544 This modifier shows the version number of @command{ar}.
545 @end table
546
547 The @command{ar} program also supports some command-line options which
548 are neither modifiers nor actions, but which do change its behaviour
549 in specific ways:
550
551 @table @samp
552 @item --help
553 Displays the list of command-line options supported by @command{ar}
554 and then exits.
555
556 @item --version
557 Displays 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
561 compatibility with AIX. The behaviour produced by this option is the
562 default for @sc{gnu} @command{ar}. @command{ar} does not support any
563 of 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
568 The optional command-line switch @option{--plugin @var{name}} causes
569 @command{ar} to load the plugin called @var{name} which adds support
570 for more file formats, including object files with link-time
571 optimization information.
572
573 This option is only available if the toolchain has been built with
574 plugin support enabled.
575
576 If @option{--plugin} is not provided, but plugin support has been
577 enabled then @command{ar} iterates over the files in
578 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
579 plugin that claims the object in question is used.
580
581 Please note that this plugin search directory is @emph{not} the one
582 used by @command{ld}'s @option{-plugin} option. In order to make
583 @command{ar} use the linker plugin it must be copied into the
584 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
585 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
586 based compilations it is called @file{LLVMgold.so}. The GCC plugin
587 is always backwards compatible with earlier versions, so it is
588 sufficient to just copy the newest one.
589
590 @item --target @var{target}
591 The optional command-line switch @option{--target @var{bfdname}}
592 specifies that the archive members are in an object code format
593 different from your system's default format. See
594 @xref{Target Selection}, for more information.
595
596 @item --output @var{dirname}
597 The @option{--output} option can be used to specify a path to a
598 directory into which archive members should be extracted. If this
599 option is not specified then the current directory will be used.
600
601 Note - although the presence of this option does imply a @option{x}
602 extraction operation that option must still be included on the command
603 line.
604
605 @item --record-libdeps @var{libdeps}
606 The @option{--record-libdeps} option is identical to the @option{l} modifier,
607 just handled in long form.
608
609 @item --thin
610 @cindex creating thin archive
611 Make the specified @var{archive} a @emph{thin} archive. If it already
612 exists and is a regular archive, the existing members must be present
613 in the same directory as @var{archive}.
614
615 @end table
616 @c man end
617
618 @ignore
619 @c man begin SEEALSO ar
620 nm(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
628 ar -M [ <@var{script} ]
629 @end smallexample
630
631 @cindex MRI compatibility, @command{ar}
632 @cindex scripts, @command{ar}
633 If you use the single command-line option @samp{-M} with @command{ar}, you
634 can control its operation with a rudimentary command language. This
635 form of @command{ar} operates interactively if standard input is coming
636 directly from a terminal. During interactive use, @command{ar} prompts for
637 input (the prompt is @samp{AR >}), and continues executing even after
638 errors. If you redirect standard input to a script file, no prompts are
639 issued, and @command{ar} abandons execution (with a nonzero exit code)
640 on any error.
641
642 The @command{ar} command language is @emph{not} designed to be equivalent
643 to the command-line options; in fact, it provides somewhat less control
644 over archives. The only purpose of the command language is to ease the
645 transition to @sc{gnu} @command{ar} for developers who already have scripts
646 written for the MRI ``librarian'' program.
647
648 The syntax for the @command{ar} command language is straightforward:
649 @itemize @bullet
650 @item
651 commands are recognized in upper or lower case; for example, @code{LIST}
652 is the same as @code{list}. In the following descriptions, commands are
653 shown in upper case for clarity.
654
655 @item
656 a single command may appear on each line; it is the first word on the
657 line.
658
659 @item
660 empty lines are allowed, and have no effect.
661
662 @item
663 comments are allowed; text after either of the characters @samp{*}
664 or @samp{;} is ignored.
665
666 @item
667 Whenever you use a list of names as part of the argument to an @command{ar}
668 command, you can separate the individual names with either commas or
669 blanks. Commas are shown in the explanations below, for clarity.
670
671 @item
672 @samp{+} is used as a line continuation character; if @samp{+} appears
673 at the end of a line, the text on the following line is considered part
674 of the current command.
675 @end itemize
676
677 Here 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
681 a temporary file required for most of the other commands.
682
683 @code{SAVE} commits the changes so far specified by the script. Prior
684 to @code{SAVE}, commands affect only the temporary copy of the current
685 archive.
686
687 @table @code
688 @item ADDLIB @var{archive}
689 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
690 Add all the contents of @var{archive} (or, if specified, each named
691 @var{module} from @var{archive}) to the current archive.
692
693 Requires 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..."
698 Add each named @var{member} as a module in the current archive.
699
700 Requires prior use of @code{OPEN} or @code{CREATE}.
701
702 @item CLEAR
703 Discard the contents of the current archive, canceling the effect of
704 any operations since the last @code{SAVE}. May be executed (with no
705 effect) even if no current archive is specified.
706
707 @item CREATE @var{archive}
708 Creates an archive, and makes it the current archive (required for many
709 other commands). The new archive is created with a temporary name; it
710 is not actually saved as @var{archive} until you use @code{SAVE}.
711 You can overwrite existing archives; similarly, the contents of any
712 existing file named @var{archive} will not be destroyed until @code{SAVE}.
713
714 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
715 Delete each listed @var{module} from the current archive; equivalent to
716 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
717
718 Requires 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}
722 List each named @var{module} present in @var{archive}. The separate
723 command @code{VERBOSE} specifies the form of the output: when verbose
724 output 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
728 Output normally goes to the standard output stream; however, if you
729 specify @var{outputfile} as a final argument, @command{ar} directs the
730 output to that file.
731
732 @item END
733 Exit from @command{ar}, with a @code{0} exit code to indicate successful
734 completion. This command does not save the output file; if you have
735 changed the current archive since the last @code{SAVE} command, those
736 changes are lost.
737
738 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
739 Extract each named @var{module} from the current archive, writing them
740 into the current directory as separate files. Equivalent to @samp{ar -x
741 @var{archive} @var{module}@dots{}}.
742
743 Requires 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
753 Display full contents of the current archive, in ``verbose'' style
754 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
755 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
756 enhancement, rather than present for MRI compatibility.)
757
758 Requires prior use of @code{OPEN} or @code{CREATE}.
759
760 @item OPEN @var{archive}
761 Opens an existing archive for use as the current archive (required for
762 many other commands). Any changes as the result of subsequent commands
763 will not actually affect @var{archive} until you next use @code{SAVE}.
764
765 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
766 In the current archive, replace each existing @var{module} (named in
767 the @code{REPLACE} arguments) from files in the current working directory.
768 To execute this command without errors, both the file, and the module in
769 the current archive, must exist.
770
771 Requires prior use of @code{OPEN} or @code{CREATE}.
772
773 @item VERBOSE
774 Toggle an internal flag governing the output from @code{DIRECTORY}.
775 When the flag is on, @code{DIRECTORY} output matches output from
776 @samp{ar -tv }@dots{}.
777
778 @item SAVE
779 Commit your changes to the current archive, and actually save it as a
780 file with the name specified in the last @code{CREATE} or @code{OPEN}
781 command.
782
783 Requires 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
792 The @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
805 nm [@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{}.
844 If no object files are listed as arguments, @command{nm} assumes the file
845 @file{a.out}.
846
847 For each symbol, @command{nm} shows:
848
849 @itemize @bullet
850 @item
851 The symbol value, in the radix selected by options (see below), or
852 hexadecimal by default.
853
854 @item
855 The symbol type. At least the following types are used; others are, as
856 well, depending on the object file format. If lowercase, the symbol is
857 usually local; if uppercase, the symbol is global (external). There
858 are however a few lowercase symbols that are shown for special global
859 symbols (@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
865 The symbol's value is absolute, and will not be changed by further
866 linking.
867
868 @item B
869 @itemx b
870 The symbol is in the BSS data section. This section typically
871 contains zero-initialized or uninitialized data, although the exact
872 behavior is system dependent.
873
874 @item C
875 @itemx c
876 The symbol is common. Common symbols are uninitialized data. When
877 linking, multiple common symbols may appear with the same name. If the
878 symbol is defined anywhere, the common symbols are treated as undefined
879 references.
880 @ifclear man
881 For more details on common symbols, see the discussion of
882 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
883 @end ifclear
884 The lower case @var{c} character is used when the symbol is in a
885 special section for small commons.
886
887 @item D
888 @itemx d
889 The symbol is in the initialized data section.
890
891 @item G
892 @itemx g
893 The symbol is in an initialized data section for small objects. Some
894 object file formats permit more efficient access to small data objects,
895 such as a global int variable as opposed to a large global array.
896
897 @item i
898 For PE format files this indicates that the symbol is in a section
899 specific to the implementation of DLLs.
900
901 For ELF format files this indicates that the symbol is an indirect
902 function. This is a GNU extension to the standard set of ELF symbol
903 types. It indicates a symbol which if referenced by a relocation does
904 not evaluate to its address, but instead must be invoked at runtime.
905 The runtime execution will then return the value to be used in the
906 relocation.
907
908 Note - the actual symbols display for GNU indirect symbols is
909 controlled by the @option{--ifunc-chars} command line option. If this
910 option has been provided then the first character in the string will
911 be used for global indirect function symbols. If the string contains
912 a second character then that will be used for local indirect function
913 symbols.
914
915 @item I
916 The symbol is an indirect reference to another symbol.
917
918 @item N
919 The symbol is a debugging symbol.
920
921 @item n
922 The symbol is in a non-data, non-code, non-debug read-only section.
923
924 @item p
925 The symbol is in a stack unwind section.
926
927 @item R
928 @itemx r
929 The symbol is in a read only data section.
930
931 @item S
932 @itemx s
933 The symbol is in an uninitialized or zero-initialized data section
934 for small objects.
935
936 @item T
937 @itemx t
938 The symbol is in the text (code) section.
939
940 @item U
941 The symbol is undefined.
942
943 @item u
944 The symbol is a unique global symbol. This is a GNU extension to the
945 standard set of ELF symbol bindings. For such a symbol the dynamic linker
946 will make sure that in the entire process there is just one symbol with
947 this name and type in use.
948
949 @item V
950 @itemx v
951 The symbol is a weak object. When a weak defined symbol is linked with
952 a normal defined symbol, the normal defined symbol is used with no error.
953 When a weak undefined symbol is linked and the symbol is not defined,
954 the value of the weak symbol becomes zero with no error. On some
955 systems, uppercase indicates that a default value has been specified.
956
957 @item W
958 @itemx w
959 The symbol is a weak symbol that has not been specifically tagged as a
960 weak object symbol. When a weak defined symbol is linked with a normal
961 defined symbol, the normal defined symbol is used with no error.
962 When a weak undefined symbol is linked and the symbol is not defined,
963 the value of the symbol is determined in a system-specific manner without
964 error. On some systems, uppercase indicates that a default value has been
965 specified.
966
967 @item -
968 The symbol is a stabs symbol in an a.out object file. In this case, the
969 next values printed are the stabs other field, the stabs desc field, and
970 the stab type. Stabs symbols are used to hold debugging information.
971
972 @item ?
973 The symbol type is unknown, or object file format specific.
974 @end table
975
976 @item
977 The symbol name. If a symbol has version information associated with it,
978 then the version information is displayed as well. If the versioned
979 symbol is undefined or hidden from linker, the version string is displayed
980 as 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
982 resolving unversioned references to the symbol, then it is displayed as a
983 suffix 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
989 The long and short forms of options, shown here as alternatives, are
990 equivalent.
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
999 Precede each symbol by the name of the input file (or archive member)
1000 in which it was found, rather than identifying the input file once only,
1001 before all of its symbols.
1002
1003 @item -a
1004 @itemx --debug-syms
1005 @cindex debugging symbols
1006 Display all symbols, even debugger-only symbols; normally these are not
1007 listed.
1008
1009 @item -B
1010 @cindex @command{nm} format
1011 @cindex @command{nm} compatibility
1012 The 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
1017 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1018 Besides removing any initial underscore prepended by the system, this
1019 makes C++ function names readable. Different compilers have different
1020 mangling styles. The optional demangling style argument can be used to
1021 choose an appropriate demangling style for your compiler. @xref{c++filt},
1022 for more information on demangling.
1023
1024 @item --no-demangle
1025 Do 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
1031 Enables or disables a limit on the amount of recursion performed
1032 whilst demangling strings. Since the name mangling formats allow for
1033 an infinite level of recursion it is possible to create strings whose
1034 decoding will exhaust the amount of stack space available on the host
1035 machine, triggering a memory fault. The limit tries to prevent this
1036 from happening by restricting recursion to 2048 levels of nesting.
1037
1038 The default is for this limit to be enabled, but disabling it may be
1039 necessary in order to demangle truly complicated names. Note however
1040 that if the recursion limit is disabled then stack exhaustion is
1041 possible and any bug reports about such an event will be rejected.
1042
1043 @item -D
1044 @itemx --dynamic
1045 @cindex dynamic symbols
1046 Display the dynamic symbols rather than the normal symbols. This is
1047 only meaningful for dynamic objects, such as certain types of shared
1048 libraries.
1049
1050 @item -f @var{format}
1051 @itemx --format=@var{format}
1052 @cindex @command{nm} format
1053 @cindex @command{nm} compatibility
1054 Use the output format @var{format}, which can be @code{bsd},
1055 @code{sysv}, @code{posix} or @code{just-symbols}. The default is @code{bsd}.
1056 Only the first character of @var{format} is significant; it can be
1057 either upper or lower case.
1058
1059 @item -g
1060 @itemx --extern-only
1061 @cindex external symbols
1062 Display only external symbols.
1063
1064 @item -h
1065 @itemx --help
1066 Show a summary of the options to @command{nm} and exit.
1067
1068 @item --ifunc-chars=@var{CHARS}
1069 When display GNU indirect function symbols @command{nm} will default
1070 to using the @code{i} character for both local indirect functions and
1071 global indirect functions. The @option{--ifunc-chars} option allows
1072 the user to specify a string containing one or two characters. The
1073 first character will be used for global indirect function symbols and
1074 the second character, if present, will be used for local indirect
1075 function symbols.
1076
1077 @item j
1078 The same as @option{--format=just-symbols}.
1079
1080 @item -l
1081 @itemx --line-numbers
1082 @cindex symbol line numbers
1083 For each symbol, use debugging information to try to find a filename and
1084 line number. For a defined symbol, look for the line number of the
1085 address of the symbol. For an undefined symbol, look for the line
1086 number of a relocation entry which refers to the symbol. If line number
1087 information can be found, print it after the other symbol information.
1088
1089 @item --inlines
1090 @cindex objdump inlines
1091 When option @option{-l} is active, if the address belongs to a
1092 function that was inlined, then this option causes the source
1093 information for all enclosing scopes back to the first non-inlined
1094 function 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}
1097 will also be printed.
1098
1099 @item -n
1100 @itemx -v
1101 @itemx --numeric-sort
1102 Sort symbols numerically by their addresses, rather than alphabetically
1103 by their names.
1104
1105 @item -p
1106 @itemx --no-sort
1107 @cindex sorting symbols
1108 Do not bother to sort the symbols in any order; print them in the order
1109 encountered.
1110
1111 @item -P
1112 @itemx --portability
1113 Use the POSIX.2 standard output format instead of the default format.
1114 Equivalent to @samp{-f posix}.
1115
1116 @item -r
1117 @itemx --reverse-sort
1118 Reverse the order of the sort (whether numeric or alphabetic); let the
1119 last come first.
1120
1121 @item -S
1122 @itemx --print-size
1123 Print both value and size of defined symbols for the @code{bsd} output style.
1124 This option has no effect for object formats that do not record symbol
1125 sizes, unless @samp{--size-sort} is also used in which case a
1126 calculated size is displayed.
1127
1128 @item -s
1129 @itemx --print-armap
1130 @cindex symbol index, listing
1131 When listing symbols from archive members, include the index: a mapping
1132 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1133 contain definitions for which names.
1134
1135 @item -t @var{radix}
1136 @itemx --radix=@var{radix}
1137 Use @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
1144 Display only undefined symbols (those external to each object file).
1145 By default both defined and undefined symbols are displayed.
1146
1147 @item -U
1148 @itemx --defined-only
1149 @cindex external symbols
1150 @cindex undefined symbols
1151 Display only defined symbols for each object file.
1152 By default both defined and undefined symbols are displayed.
1153
1154 @item -V
1155 @itemx --version
1156 Show the version number of @command{nm} and exit.
1157
1158 @item -X
1159 This 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
1162 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1163
1164 @item --plugin @var{name}
1165 @cindex plugins
1166 Load the plugin called @var{name} to add support for extra target
1167 types. This option is only available if the toolchain has been built
1168 with plugin support enabled.
1169
1170 If @option{--plugin} is not provided, but plugin support has been
1171 enabled then @command{nm} iterates over the files in
1172 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1173 plugin that claims the object in question is used.
1174
1175 Please note that this plugin search directory is @emph{not} the one
1176 used by @command{ld}'s @option{-plugin} option. In order to make
1177 @command{nm} use the linker plugin it must be copied into the
1178 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1179 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1180 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1181 is always backwards compatible with earlier versions, so it is
1182 sufficient to just copy the newest one.
1183
1184 @item --size-sort
1185 Sort symbols by size. For ELF objects symbol sizes are read from the
1186 ELF, for other object types the symbol sizes are computed as the
1187 difference between the value of the symbol and the value of the symbol
1188 with the next higher value. If the @code{bsd} output format is used
1189 the 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
1192 Note - this option does not work if @option{--undefined-only} has been
1193 enabled as undefined symbols have no size.
1194
1195 @item --special-syms
1196 Display symbols which have a target-specific special meaning. These
1197 symbols are usually used by the target for some special processing and
1198 are not normally helpful when included in the normal symbol lists.
1199 For example for ARM targets this option would skip the mapping symbols
1200 used to mark transitions between ARM code, THUMB code and data.
1201
1202 @item --synthetic
1203 Include synthetic symbols in the output. These are special symbols
1204 created by the linker for various purposes. They are not shown by
1205 default since they are not part of the binary's original source code.
1206
1207 @item --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
1208 Controls the display of UTF-8 encoded multibyte characters in strings.
1209 The default (@option{--unicode=default}) is to give them no special
1210 treatment. The @option{--unicode=locale} option displays the sequence
1211 in the current locale, which may or may not support them. The options
1212 @option{--unicode=hex} and @option{--unicode=invalid} display them as
1213 hex byte sequences enclosed by either angle brackets or curly braces.
1214
1215 The @option{--unicode=escape} option displays them as escape sequences
1216 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
1217 them as escape sequences highlighted in red (if supported by the
1218 output device). The colouring is intended to draw attention to the
1219 presence of unicode sequences where they might not be expected.
1220
1221 @item -W
1222 @itemx --no-weak
1223 Do not display weak symbols.
1224
1225 @item --with-symbol-versions
1226 @item --without-symbol-versions
1227 Enables or disables the display of symbol version information. The
1228 version string is displayed as a suffix to the symbol name, preceded
1229 by an @@ character. For example @samp{foo@@VER_1}. If the version is
1230 the default version to be used when resolving unversioned references
1231 to the symbol then it is displayed as a suffix preceded by two @@
1232 characters. For example @samp{foo@@@@VER_2}. By default, symbol
1233 version information is displayed.
1234
1235 @item --target=@var{bfdname}
1236 @cindex object code format
1237 Specify 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
1246 ar(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
1257 objcopy [@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
1352 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1353 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1354 read and write the object files. It can write the destination object
1355 file in a format different from that of the source object file. The
1356 exact behavior of @command{objcopy} is controlled by command-line options.
1357 Note that @command{objcopy} should be able to copy a fully linked file
1358 between any two formats. However, copying a relocatable object file
1359 between any two formats may not work as expected.
1360
1361 @command{objcopy} creates temporary files to do its translations and
1362 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1363 translation work; it has access to all the formats described in @sc{bfd}
1364 and thus is able to recognize most formats without being told
1365 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1366
1367 @command{objcopy} can be used to generate S-records by using an output
1368 target 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
1371 output target of @samp{binary} (e.g., use @option{-O binary}). When
1372 @command{objcopy} generates a raw binary file, it will essentially produce
1373 a memory dump of the contents of the input object file. All symbols and
1374 relocation information will be discarded. The memory dump will start at
1375 the load address of the lowest section copied into the output file.
1376
1377 When generating an S-record or a raw binary file, it may be helpful to
1378 use @option{-S} to remove sections containing debugging information. In
1379 some cases @option{-R} will be useful to remove sections which contain
1380 information that is not needed by the binary file.
1381
1382 Note---@command{objcopy} is not able to change the endianness of its input
1383 files. 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
1385 same 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}
1395 The input and output files, respectively.
1396 If you do not specify @var{outfile}, @command{objcopy} creates a
1397 temporary file and destructively renames the result with
1398 the name of @var{infile}.
1399
1400 @item -I @var{bfdname}
1401 @itemx --input-target=@var{bfdname}
1402 Consider the source file's object format to be @var{bfdname}, rather than
1403 attempting to deduce it. @xref{Target Selection}, for more information.
1404
1405 @item -O @var{bfdname}
1406 @itemx --output-target=@var{bfdname}
1407 Write 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}
1412 Use @var{bfdname} as the object format for both the input and the output
1413 file; i.e., simply transfer data from source to destination with no
1414 translation. @xref{Target Selection}, for more information.
1415
1416 @item -B @var{bfdarch}
1417 @itemx --binary-architecture=@var{bfdarch}
1418 Useful when transforming a architecture-less input file into an object file.
1419 In this case the output architecture can be set to @var{bfdarch}. This
1420 option will be ignored if the input file has a known @var{bfdarch}. You
1421 can access this binary data inside a program by referencing the special
1422 symbols that are created by the conversion process. These symbols are
1423 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1424 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1425 an object file and then access it in your code using these symbols.
1426
1427 @item -j @var{sectionpattern}
1428 @itemx --only-section=@var{sectionpattern}
1429 Copy only the indicated sections from the input file to the output file.
1430 This option may be given more than once. Note that using this option
1431 inappropriately may make the output file unusable. Wildcard
1432 characters are accepted in @var{sectionpattern}.
1433
1434 If the first character of @var{sectionpattern} is the exclamation
1435 point (!) then matching sections will not be copied, even if earlier
1436 use of @option{--only-section} on the same command line would
1437 otherwise copy it. For example:
1438
1439 @smallexample
1440 --only-section=.text.* --only-section=!.text.foo
1441 @end smallexample
1442
1443 will copy all sectinos matching '.text.*' but not the section
1444 '.text.foo'.
1445
1446 @item -R @var{sectionpattern}
1447 @itemx --remove-section=@var{sectionpattern}
1448 Remove any section matching @var{sectionpattern} from the output file.
1449 This option may be given more than once. Note that using this option
1450 inappropriately may make the output file unusable. Wildcard
1451 characters are accepted in @var{sectionpattern}. Using both the
1452 @option{-j} and @option{-R} options together results in undefined
1453 behaviour.
1454
1455 If the first character of @var{sectionpattern} is the exclamation
1456 point (!) then matching sections will not be removed even if an
1457 earlier use of @option{--remove-section} on the same command line
1458 would otherwise remove it. For example:
1459
1460 @smallexample
1461 --remove-section=.text.* --remove-section=!.text.foo
1462 @end smallexample
1463
1464 will remove all sections matching the pattern '.text.*', but will not
1465 remove the section '.text.foo'.
1466
1467 @item --keep-section=@var{sectionpattern}
1468 When removing sections from the output file, keep sections that match
1469 @var{sectionpattern}.
1470
1471 @item --remove-relocations=@var{sectionpattern}
1472 Remove non-dynamic relocations from the output file for any section
1473 matching @var{sectionpattern}. This option may be given more than
1474 once. Note that using this option inappropriately may make the output
1475 file unusable, and attempting to remove a dynamic relocation section
1476 such as @samp{.rela.plt} from an executable or shared library with
1477 @option{--remove-relocations=.plt} will not work. Wildcard characters
1478 are accepted in @var{sectionpattern}.
1479 For example:
1480
1481 @smallexample
1482 --remove-relocations=.text.*
1483 @end smallexample
1484
1485 will remove the relocations for all sections matching the pattern
1486 '.text.*'.
1487
1488 If the first character of @var{sectionpattern} is the exclamation
1489 point (!) then matching sections will not have their relocation
1490 removed even if an earlier use of @option{--remove-relocations} on the
1491 same command line would otherwise cause the relocations to be removed.
1492 For example:
1493
1494 @smallexample
1495 --remove-relocations=.text.* --remove-relocations=!.text.foo
1496 @end smallexample
1497
1498 will 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
1503 Strip section header This option is specific to ELF files.
1504 Implies @option{--strip-all} and @option{--merge-notes}.
1505
1506 @item -S
1507 @itemx --strip-all
1508 Do not copy relocation and symbol information from the source file.
1509 Also deletes debug sections.
1510
1511 @item -g
1512 @itemx --strip-debug
1513 Do not copy debugging symbols or sections from the source file.
1514
1515 @item --strip-unneeded
1516 Remove all symbols that are not needed for relocation processing in
1517 addition to debugging symbols and sections stripped by
1518 @option{--strip-debug}.
1519
1520 @item -K @var{symbolname}
1521 @itemx --keep-symbol=@var{symbolname}
1522 When stripping symbols, keep symbol @var{symbolname} even if it would
1523 normally be stripped. This option may be given more than once.
1524
1525 @item -N @var{symbolname}
1526 @itemx --strip-symbol=@var{symbolname}
1527 Do not copy symbol @var{symbolname} from the source file. This option
1528 may be given more than once.
1529
1530 @item --strip-unneeded-symbol=@var{symbolname}
1531 Do not copy symbol @var{symbolname} from the source file unless it is needed
1532 by a relocation. This option may be given more than once.
1533
1534 @item -G @var{symbolname}
1535 @itemx --keep-global-symbol=@var{symbolname}
1536 Keep only symbol @var{symbolname} global. Make all other symbols local
1537 to the file, so that they are not visible externally. This option may
1538 be given more than once. Note: this option cannot be used in
1539 conjunction with the @option{--globalize-symbol} or
1540 @option{--globalize-symbols} options.
1541
1542 @item --localize-hidden
1543 In an ELF object, mark all symbols that have hidden or internal visibility
1544 as local. This option applies on top of symbol-specific localization options
1545 such as @option{-L}.
1546
1547 @item -L @var{symbolname}
1548 @itemx --localize-symbol=@var{symbolname}
1549 Convert a global or weak symbol called @var{symbolname} into a local
1550 symbol, so that it is not visible externally. This option may be
1551 given more than once. Note - unique symbols are not converted.
1552
1553 @item -W @var{symbolname}
1554 @itemx --weaken-symbol=@var{symbolname}
1555 Make symbol @var{symbolname} weak. This option may be given more than once.
1556
1557 @item --globalize-symbol=@var{symbolname}
1558 Give symbol @var{symbolname} global scoping so that it is visible
1559 outside of the file in which it is defined. This option may be given
1560 more than once. Note: this option cannot be used in conjunction with
1561 the @option{-G} or @option{--keep-global-symbol} options.
1562
1563 @item -w
1564 @itemx --wildcard
1565 Permit regular expressions in @var{symbolname}s used in other command
1566 line options. The question mark (?), asterisk (*), backslash (\) and
1567 square brackets ([]) operators can be used anywhere in the symbol
1568 name. If the first character of the symbol name is the exclamation
1569 point (!) then the sense of the switch is reversed for that symbol.
1570 For example:
1571
1572 @smallexample
1573 -w -W !foo -W fo*
1574 @end smallexample
1575
1576 would cause objcopy to weaken all symbols that start with ``fo''
1577 except for the symbol ``foo''.
1578
1579 @item -x
1580 @itemx --discard-all
1581 Do 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
1586 Do 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}
1591 If interleaving has been enabled via the @option{--interleave} option
1592 then 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}]
1598 Only copy a range out of every @var{breadth} bytes. (Header data is
1599 not affected). Select which byte in the range begins the copy with
1600 the @option{--byte} option. Select the width of the range with the
1601 @option{--interleave-width} option.
1602
1603 This option is useful for creating files to program @sc{rom}. It is
1604 typically 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
1608 The 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
1610 from the input to the output.
1611
1612 @item --interleave-width=@var{width}
1613 When used with the @option{--interleave} option, copy @var{width}
1614 bytes at a time. The start of the range of bytes to be copied is set
1615 by the @option{--byte} option, and the extent of the range is set with
1616 the @option{--interleave} option.
1617
1618 The default value for this option is 1. The value of @var{width} plus
1619 the @var{byte} value set by the @option{--byte} option must not exceed
1620 the interleave breadth set by the @option{--interleave} option.
1621
1622 This option can be used to create images for two 16-bit flashes interleaved
1623 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1624 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1625 commands. If the input was '12345678' then the outputs would be
1626 '1256' and '3478' respectively.
1627
1628 @item -p
1629 @itemx --preserve-dates
1630 Set the access and modification dates of the output file to be the same
1631 as those of the input file.
1632
1633 This option also copies the date stored in a PE format file's header,
1634 unless the SOURCE_DATE_EPOCH environment variable is defined. If it
1635 is defined then this variable will be used as the date stored in the
1636 header, 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
1642 Operate in @emph{deterministic} mode. When copying archive members
1643 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1644 and use consistent file modes for all files.
1645
1646 If @file{binutils} was configured with
1647 @option{--enable-deterministic-archives}, then this mode is on by default.
1648 It 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
1654 Do @emph{not} operate in @emph{deterministic} mode. This is the
1655 inverse of the @option{-D} option, above: when copying archive members
1656 and writing the archive index, use their actual UID, GID, timestamp,
1657 and file mode values.
1658
1659 This is the default unless @file{binutils} was configured with
1660 @option{--enable-deterministic-archives}.
1661
1662 @item --debugging
1663 Convert debugging information, if possible. This is not the default
1664 because only certain debugging formats are supported, and the
1665 conversion process can be time consuming.
1666
1667 @item --gap-fill @var{val}
1668 Fill gaps between sections with @var{val}. This operation applies to
1669 the @emph{load address} (LMA) of the sections. It is done by increasing
1670 the size of the section with the lower address, and filling in the extra
1671 space created with @var{val}.
1672
1673 @item --pad-to @var{address}
1674 Pad the output file up to the load address @var{address}. This is
1675 done by increasing the size of the last section. The extra space is
1676 filled in with the value specified by @option{--gap-fill} (default zero).
1677
1678 @item --set-start @var{val}
1679 Set the start address (also known as the entry address) of the new
1680 file to @var{val}. Not all object file formats support setting the
1681 start address.
1682
1683 @item --change-start @var{incr}
1684 @itemx --adjust-start @var{incr}
1685 @cindex changing start address
1686 Change the start address (also known as the entry address) by adding
1687 @var{incr}. Not all object file formats support setting the start
1688 address.
1689
1690 @item --change-addresses @var{incr}
1691 @itemx --adjust-vma @var{incr}
1692 @cindex changing object addresses
1693 Change the VMA and LMA addresses of all sections, as well as the start
1694 address, by adding @var{incr}. Some object file formats do not permit
1695 section addresses to be changed arbitrarily. Note that this does not
1696 relocate the sections; if the program expects sections to be loaded at a
1697 certain address, and this option is used to change the sections such
1698 that 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
1703 Set or change both the VMA address and the LMA address of any section
1704 matching @var{sectionpattern}. If @samp{=} is used, the section
1705 address is set to @var{val}. Otherwise, @var{val} is added to or
1706 subtracted from the section address. See the comments under
1707 @option{--change-addresses}, above. If @var{sectionpattern} does not
1708 match 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
1713 Set or change the LMA address of any sections matching
1714 @var{sectionpattern}. The LMA address is the address where the
1715 section will be loaded into memory at program load time. Normally
1716 this is the same as the VMA address, which is the address of the
1717 section at program run time, but on some systems, especially those
1718 where a program is held in ROM, the two can be different. If @samp{=}
1719 is used, the section address is set to @var{val}. Otherwise,
1720 @var{val} is added to or subtracted from the section address. See the
1721 comments under @option{--change-addresses}, above. If
1722 @var{sectionpattern} does not match any sections in the input file, a
1723 warning 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
1727 Set or change the VMA address of any section matching
1728 @var{sectionpattern}. The VMA address is the address where the
1729 section will be located once the program has started executing.
1730 Normally this is the same as the LMA address, which is the address
1731 where the section will be loaded into memory, but on some systems,
1732 especially those where a program is held in ROM, the two can be
1733 different. If @samp{=} is used, the section address is set to
1734 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1735 section address. See the comments under @option{--change-addresses},
1736 above. If @var{sectionpattern} does not match any sections in the
1737 input file, a warning will be issued, unless
1738 @option{--no-change-warnings} is used.
1739
1740 @item --change-warnings
1741 @itemx --adjust-warnings
1742 If @option{--change-section-address} or @option{--change-section-lma} or
1743 @option{--change-section-vma} is used, and the section pattern does not
1744 match any sections, issue a warning. This is the default.
1745
1746 @item --no-change-warnings
1747 @itemx --no-adjust-warnings
1748 Do not issue a warning if @option{--change-section-address} or
1749 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1750 if the section pattern does not match any sections.
1751
1752 @item --set-section-flags @var{sectionpattern}=@var{flags}
1753 Set the flags for any sections matching @var{sectionpattern}. The
1754 @var{flags} argument is a comma separated string of flag names. The
1755 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1756 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1757 @samp{exclude}, @samp{share}, @samp{debug}, and @samp{large}.
1758 You can set the @samp{contents} flag for a section which does not have
1759 contents, but it is not meaningful to clear the @samp{contents} flag of a
1760 section which does have contents--just remove the section instead. Not all
1761 flags are meaningful for all object file formats. In particular the
1762 @samp{share} flag is only meaningful for COFF format files and not for ELF
1763 format files. The ELF x86-64 specific flag @samp{large} corresponds to
1764 SHF_X86_64_LARGE.
1765
1766 @item --set-section-alignment @var{sectionpattern}=@var{align}
1767 Set the alignment for any sections matching @var{sectionpattern}.
1768 @var{align} specifies the alignment in bytes and must be a power of
1769 two, i.e. 1, 2, 4, 8@dots{}.
1770
1771 @item --add-section @var{sectionname}=@var{filename}
1772 Add a new section named @var{sectionname} while copying the file. The
1773 contents of the new section are taken from the file @var{filename}. The
1774 size of the section will be the size of the file. This option only
1775 works on file formats which can support sections with arbitrary names.
1776 Note - it may be necessary to use the @option{--set-section-flags}
1777 option to set the attributes of the newly created section.
1778
1779 @item --dump-section @var{sectionname}=@var{filename}
1780 Place the contents of section named @var{sectionname} into the file
1781 @var{filename}, overwriting any contents that may have been there
1782 previously. This option is the inverse of @option{--add-section}.
1783 This option is similar to the @option{--only-section} option except
1784 that it does not create a formatted file, it just dumps the contents
1785 as raw binary data, without applying any relocations. The option can
1786 be specified more than once.
1787
1788 @item --update-section @var{sectionname}=@var{filename}
1789 Replace the existing contents of a section named @var{sectionname}
1790 with the contents of file @var{filename}. The size of the section
1791 will be adjusted to the size of the file. The section flags for
1792 @var{sectionname} will be unchanged. For ELF format files the section
1793 to segment mapping will also remain unchanged, something which is not
1794 possible using @option{--remove-section} followed by
1795 @option{--add-section}. The option can be specified more than once.
1796
1797 Note - it is possible to use @option{--rename-section} and
1798 @option{--update-section} to both update and rename a section from one
1799 command line. In this case, pass the original section name to
1800 @option{--update-section}, and the original and new section names to
1801 @option{--rename-section}.
1802
1803 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1804 Add a new symbol named @var{name} while copying the file. This option may be
1805 specified multiple times. If the @var{section} is given, the symbol will be
1806 associated with and relative to that section, otherwise it will be an ABS
1807 symbol. Specifying an undefined section will result in a fatal error. There
1808 is no check for the value, it will be taken as specified. Symbol flags can
1809 be specified and not all flags will be meaningful for all object file
1810 formats. By default, the symbol will be global. The special flag
1811 'before=@var{othersym}' will insert the new symbol in front of the specified
1812 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1813 symbol table in the order they appear.
1814
1815 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1816 Rename a section from @var{oldname} to @var{newname}, optionally
1817 changing the section's flags to @var{flags} in the process. This has
1818 the advantage over using a linker script to perform the rename in that
1819 the output stays as an object file and does not become a linked
1820 executable. This option accepts the same set of flags as the
1821 @option{--sect-section-flags} option.
1822
1823 This option is particularly helpful when the input format is binary,
1824 since this will always create a section called .data. If for example,
1825 you wanted instead to create a section called .rodata containing binary
1826 data you could use the following command line to achieve it:
1827
1828 @smallexample
1829 objcopy -I binary -O <output_format> -B <architecture> \
1830 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1831 <input_binary_file> <output_object_file>
1832 @end smallexample
1833
1834 @item --long-section-names @{enable,disable,keep@}
1835 Controls the handling of long section names when processing @code{COFF}
1836 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1837 is to preserve long section names if any are present in the input file.
1838 The @samp{enable} and @samp{disable} options forcibly enable or disable
1839 the use of long section names in the output object; when @samp{disable}
1840 is in effect, any long section names in the input object will be truncated.
1841 The @samp{enable} option will only emit long section names if any are
1842 present in the inputs; this is mostly the same as @samp{keep}, but it
1843 is left undefined whether the @samp{enable} option might force the
1844 creation of an empty string table in the output file.
1845
1846 @item --change-leading-char
1847 Some object file formats use special characters at the start of
1848 symbols. The most common such character is underscore, which compilers
1849 often add before every symbol. This option tells @command{objcopy} to
1850 change the leading character of every symbol when it converts between
1851 object file formats. If the object file formats use the same leading
1852 character, this option has no effect. Otherwise, it will add a
1853 character, or remove a character, or change a character, as
1854 appropriate.
1855
1856 @item --remove-leading-char
1857 If the first character of a global symbol is a special symbol leading
1858 character used by the object file format, remove the character. The
1859 most common symbol leading character is underscore. This option will
1860 remove a leading underscore from all global symbols. This can be useful
1861 if you want to link together objects of different file formats with
1862 different conventions for symbol names. This is different from
1863 @option{--change-leading-char} because it always changes the symbol name
1864 when appropriate, regardless of the object file format of the output
1865 file.
1866
1867 @item --reverse-bytes=@var{num}
1868 Reverse the bytes in a section with output contents. A section length must
1869 be evenly divisible by the value given in order for the swap to be able to
1870 take place. Reversing takes place before the interleaving is performed.
1871
1872 This option is used typically in generating ROM images for problematic
1873 target systems. For example, on some target boards, the 32-bit words
1874 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1875 regardless of the CPU byte order. Depending on the programming model, the
1876 endianness of the ROM may need to be modified.
1877
1878 Consider a simple file with a section containing the following eight
1879 bytes: @code{12345678}.
1880
1881 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1882 output file would be ordered @code{21436587}.
1883
1884 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1885 output file would be ordered @code{43218765}.
1886
1887 By using @samp{--reverse-bytes=2} for the above example, followed by
1888 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1889 output file would be ordered @code{34127856}.
1890
1891 @item --srec-len=@var{ival}
1892 Meaningful only for srec output. Set the maximum length of the Srecords
1893 being produced to @var{ival}. This length covers both address, data and
1894 crc fields.
1895
1896 @item --srec-forceS3
1897 Meaningful only for srec output. Avoid generation of S1/S2 records,
1898 creating S3-only record format.
1899
1900 @item --redefine-sym @var{old}=@var{new}
1901 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1902 when one is trying link two things together for which you have no
1903 source, and there are name collisions.
1904
1905 @item --redefine-syms=@var{filename}
1906 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1907 listed in the file @var{filename}. @var{filename} is simply a flat file,
1908 with one symbol pair per line. Line comments may be introduced by the hash
1909 character. This option may be given more than once.
1910
1911 @item --weaken
1912 Change all global symbols in the file to be weak. This can be useful
1913 when building an object which will be linked against other objects using
1914 the @option{-R} option to the linker. This option is only effective when
1915 using an object file format which supports weak symbols.
1916
1917 @item --keep-symbols=@var{filename}
1918 Apply @option{--keep-symbol} option to each symbol listed in the file
1919 @var{filename}. @var{filename} is simply a flat file, with one symbol
1920 name per line. Line comments may be introduced by the hash character.
1921 This option may be given more than once.
1922
1923 @item --strip-symbols=@var{filename}
1924 Apply @option{--strip-symbol} option to each symbol listed in the file
1925 @var{filename}. @var{filename} is simply a flat file, with one symbol
1926 name per line. Line comments may be introduced by the hash character.
1927 This option may be given more than once.
1928
1929 @item --strip-unneeded-symbols=@var{filename}
1930 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1931 the file @var{filename}. @var{filename} is simply a flat file, with one
1932 symbol name per line. Line comments may be introduced by the hash
1933 character. This option may be given more than once.
1934
1935 @item --keep-global-symbols=@var{filename}
1936 Apply @option{--keep-global-symbol} option to each symbol listed in the
1937 file @var{filename}. @var{filename} is simply a flat file, with one
1938 symbol name per line. Line comments may be introduced by the hash
1939 character. This option may be given more than once.
1940
1941 @item --localize-symbols=@var{filename}
1942 Apply @option{--localize-symbol} option to each symbol listed in the file
1943 @var{filename}. @var{filename} is simply a flat file, with one symbol
1944 name per line. Line comments may be introduced by the hash character.
1945 This option may be given more than once.
1946
1947 @item --globalize-symbols=@var{filename}
1948 Apply @option{--globalize-symbol} option to each symbol listed in the file
1949 @var{filename}. @var{filename} is simply a flat file, with one symbol
1950 name per line. Line comments may be introduced by the hash character.
1951 This option may be given more than once. Note: this option cannot be
1952 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1953 options.
1954
1955 @item --weaken-symbols=@var{filename}
1956 Apply @option{--weaken-symbol} option to each symbol listed in the file
1957 @var{filename}. @var{filename} is simply a flat file, with one symbol
1958 name per line. Line comments may be introduced by the hash character.
1959 This option may be given more than once.
1960
1961 @item --alt-machine-code=@var{index}
1962 If the output architecture has alternate machine codes, use the
1963 @var{index}th code instead of the default one. This is useful in case
1964 a machine is assigned an official code and the tool-chain adopts the
1965 new code, but other applications still depend on the original code
1966 being used. For ELF based architectures if the @var{index}
1967 alternative does not exist then the value is treated as an absolute
1968 number to be stored in the e_machine field of the ELF header.
1969
1970 @item --writable-text
1971 Mark the output text as writable. This option isn't meaningful for all
1972 object file formats.
1973
1974 @item --readonly-text
1975 Make the output text write protected. This option isn't meaningful for all
1976 object file formats.
1977
1978 @item --pure
1979 Mark the output file as demand paged. This option isn't meaningful for all
1980 object file formats.
1981
1982 @item --impure
1983 Mark the output file as impure. This option isn't meaningful for all
1984 object file formats.
1985
1986 @item --prefix-symbols=@var{string}
1987 Prefix all symbols in the output file with @var{string}.
1988
1989 @item --prefix-sections=@var{string}
1990 Prefix all section names in the output file with @var{string}.
1991
1992 @item --prefix-alloc-sections=@var{string}
1993 Prefix all the names of all allocated sections in the output file with
1994 @var{string}.
1995
1996 @item --add-gnu-debuglink=@var{path-to-file}
1997 Creates a .gnu_debuglink section which contains a reference to
1998 @var{path-to-file} and adds it to the output file. Note: the file at
1999 @var{path-to-file} must exist. Part of the process of adding the
2000 .gnu_debuglink section involves embedding a checksum of the contents
2001 of the debug info file into the section.
2002
2003 If the debug info file is built in one location but it is going to be
2004 installed at a later time into a different location then do not use
2005 the path to the installed location. The @option{--add-gnu-debuglink}
2006 option will fail because the installed file does not exist yet.
2007 Instead put the debug info file in the current directory and use the
2008 @option{--add-gnu-debuglink} option without any directory components,
2009 like this:
2010
2011 @smallexample
2012 objcopy --add-gnu-debuglink=foo.debug
2013 @end smallexample
2014
2015 At debug time the debugger will attempt to look for the separate debug
2016 info file in a set of known locations. The exact set of these
2017 locations varies depending upon the distribution being used, but it
2018 typically includes:
2019
2020 @table @code
2021
2022 @item * The same directory as the executable.
2023
2024 @item * A sub-directory of the directory containing the executable
2025 called .debug
2026
2027 @item * A global debug directory such as /usr/lib/debug.
2028 @end table
2029
2030 As long as the debug info file has been installed into one of these
2031 locations before the debugger is run everything should work
2032 correctly.
2033
2034 @item --keep-section-symbils
2035 When stripping a file, perhaps with @option{--strip-debug} or
2036 @option{--strip-unneeded}, retain any symbols specifying section names,
2037 which would otherwise get stripped.
2038
2039 @item --keep-file-symbols
2040 When stripping a file, perhaps with @option{--strip-debug} or
2041 @option{--strip-unneeded}, retain any symbols specifying source file names,
2042 which would otherwise get stripped.
2043
2044 @item --only-keep-debug
2045 Strip a file, removing contents of any sections that would not be
2046 stripped by @option{--strip-debug} and leaving the debugging sections
2047 intact. In ELF files, this preserves all note sections in the output.
2048
2049 Note - the section headers of the stripped sections are preserved,
2050 including their sizes, but the contents of the section are discarded.
2051 The section headers are preserved so that other tools can match up the
2052 debuginfo file with the real executable, even if that executable has
2053 been relocated to a different address space.
2054
2055 The intention is that this option will be used in conjunction with
2056 @option{--add-gnu-debuglink} to create a two part executable. One a
2057 stripped binary which will occupy less space in RAM and in a
2058 distribution and the second a debugging information file which is only
2059 needed if debugging abilities are required. The suggested procedure
2060 to create these files is as follows:
2061
2062 @enumerate
2063 @item Link the executable as normal. Assuming that it is called
2064 @code{foo} then...
2065 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2066 create a file containing the debugging info.
2067 @item Run @code{objcopy --strip-debug foo} to create a
2068 stripped executable.
2069 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2070 to add a link to the debugging info into the stripped executable.
2071 @end enumerate
2072
2073 Note---the choice of @code{.dbg} as an extension for the debug info
2074 file is arbitrary. Also the @code{--only-keep-debug} step is
2075 optional. You could instead do this:
2076
2077 @enumerate
2078 @item Link the executable as normal.
2079 @item Copy @code{foo} to @code{foo.full}
2080 @item Run @code{objcopy --strip-debug foo}
2081 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2082 @end enumerate
2083
2084 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2085 full executable. It does not have to be a file created by the
2086 @option{--only-keep-debug} switch.
2087
2088 Note---this switch is only intended for use on fully linked files. It
2089 does not make sense to use it on object files where the debugging
2090 information may be incomplete. Besides the gnu_debuglink feature
2091 currently only supports the presence of one filename containing
2092 debugging information, not multiple filenames on a one-per-object-file
2093 basis.
2094
2095 @item --strip-dwo
2096 Remove the contents of all DWARF .dwo sections, leaving the
2097 remaining debugging sections and all symbols intact.
2098 This option is intended for use by the compiler as part of
2099 the @option{-gsplit-dwarf} option, which splits debug information
2100 between the .o file and a separate .dwo file. The compiler
2101 generates all debug information in the same file, then uses
2102 the @option{--extract-dwo} option to copy the .dwo sections to
2103 the .dwo file, then the @option{--strip-dwo} option to remove
2104 those sections from the original .o file.
2105
2106 @item --extract-dwo
2107 Extract the contents of all DWARF .dwo sections. See the
2108 @option{--strip-dwo} option for more information.
2109
2110 @item --file-alignment @var{num}
2111 Specify the file alignment. Sections in the file will always begin at
2112 file offsets which are multiples of this number. This defaults to
2113 512.
2114 [This option is specific to PE targets.]
2115
2116 @item --heap @var{reserve}
2117 @itemx --heap @var{reserve},@var{commit}
2118 Specify the number of bytes of memory to reserve (and optionally commit)
2119 to be used as heap for this program.
2120 [This option is specific to PE targets.]
2121
2122 @item --image-base @var{value}
2123 Use @var{value} as the base address of your program or dll. This is
2124 the lowest memory location that will be used when your program or dll
2125 is loaded. To reduce the need to relocate and improve performance of
2126 your dlls, each should have a unique base address and not overlap any
2127 other dlls. The default is 0x400000 for executables, and 0x10000000
2128 for dlls.
2129 [This option is specific to PE targets.]
2130
2131 @item --section-alignment @var{num}
2132 Sets the section alignment field in the PE header. Sections in memory
2133 will always begin at addresses which are a multiple of this number.
2134 Defaults to 0x1000.
2135 [This option is specific to PE targets.]
2136
2137 @item --stack @var{reserve}
2138 @itemx --stack @var{reserve},@var{commit}
2139 Specify the number of bytes of memory to reserve (and optionally commit)
2140 to be used as stack for this program.
2141 [This option is specific to PE targets.]
2142
2143 @item --subsystem @var{which}
2144 @itemx --subsystem @var{which}:@var{major}
2145 @itemx --subsystem @var{which}:@var{major}.@var{minor}
2146 Specifies the subsystem under which your program will execute. The
2147 legal values for @var{which} are @code{native}, @code{windows},
2148 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2149 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2150 the subsystem version also. Numeric values are also accepted for
2151 @var{which}.
2152 [This option is specific to PE targets.]
2153
2154 @item --extract-symbol
2155 Keep the file's section flags and symbols but remove all section data.
2156 Specifically, the option:
2157
2158 @itemize
2159 @item removes the contents of all sections;
2160 @item sets the size of every section to zero; and
2161 @item sets the file's start address to zero.
2162 @end itemize
2163
2164 This option is used to build a @file{.sym} file for a VxWorks kernel.
2165 It can also be a useful way of reducing the size of a @option{--just-symbols}
2166 linker input file.
2167
2168 @item --compress-debug-sections
2169 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2170 ELF ABI. Note - if compression would actually make a section
2171 @emph{larger}, then it is not compressed.
2172
2173 @item --compress-debug-sections=none
2174 @itemx --compress-debug-sections=zlib
2175 @itemx --compress-debug-sections=zlib-gnu
2176 @itemx --compress-debug-sections=zlib-gabi
2177 @itemx --compress-debug-sections=zstd
2178 For ELF files, these options control how DWARF debug sections are
2179 compressed. @option{--compress-debug-sections=none} is equivalent
2180 to @option{--decompress-debug-sections}.
2181 @option{--compress-debug-sections=zlib} and
2182 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2183 @option{--compress-debug-sections}.
2184 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug sections
2185 using the obsoleted zlib-gnu format. The debug sections are renamed to begin
2186 with @samp{.zdebug}.
2187 @option{--compress-debug-sections=zstd} compresses DWARF debug
2188 sections using zstd. Note - if compression would actually make a section
2189 @emph{larger}, then it is not compressed nor renamed.
2190
2191 @item --decompress-debug-sections
2192 Decompress DWARF debug sections. For a @samp{.zdebug} section, the original
2193 name is restored.
2194
2195 @item --elf-stt-common=yes
2196 @itemx --elf-stt-common=no
2197 For ELF files, these options control whether common symbols should be
2198 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2199 @option{--elf-stt-common=yes} converts common symbol type to
2200 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2201 type to @code{STT_OBJECT}.
2202
2203 @item --merge-notes
2204 @itemx --no-merge-notes
2205 For ELF files, attempt (or do not attempt) to reduce the size of any
2206 SHT_NOTE type sections by removing duplicate notes.
2207
2208 @item -V
2209 @itemx --version
2210 Show the version number of @command{objcopy}.
2211
2212 @item --verilog-data-width=@var{bytes}
2213 For Verilog output, this options controls the number of bytes
2214 converted for each output data element. The input target controls the
2215 endianness of the conversion.
2216
2217 @item -v
2218 @itemx --verbose
2219 Verbose output: list all object files modified. In the case of
2220 archives, @samp{objcopy -V} lists all members of the archive.
2221
2222 @item --help
2223 Show a summary of the options to @command{objcopy}.
2224
2225 @item --info
2226 Display a list showing all architectures and object formats available.
2227 @end table
2228
2229 @c man end
2230
2231 @ignore
2232 @c man begin SEEALSO objcopy
2233 ld(1), objdump(1), and the Info entries for @file{binutils}.
2234 @c man end
2235 @end ignore
2236
2237 @node objdump
2238 @chapter objdump
2239
2240 @cindex object file information
2241 @kindex objdump
2242
2243 @c man title objdump display information from object files
2244
2245 @smallexample
2246 @c man begin SYNOPSIS objdump
2247 objdump [@option{-a}|@option{--archive-headers}]
2248 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2249 [@option{-C}|@option{--demangle}[=@var{style}] ]
2250 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2251 [@option{-D}|@option{--disassemble-all}]
2252 [@option{-z}|@option{--disassemble-zeroes}]
2253 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2254 [@option{-f}|@option{--file-headers}]
2255 [@option{-F}|@option{--file-offsets}]
2256 [@option{--file-start-context}]
2257 [@option{-g}|@option{--debugging}]
2258 [@option{-e}|@option{--debugging-tags}]
2259 [@option{-h}|@option{--section-headers}|@option{--headers}]
2260 [@option{-i}|@option{--info}]
2261 [@option{-j} @var{section}|@option{--section=}@var{section}]
2262 [@option{-l}|@option{--line-numbers}]
2263 [@option{-S}|@option{--source}]
2264 [@option{--source-comment}[=@var{text}]]
2265 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2266 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2267 [@option{-p}|@option{--private-headers}]
2268 [@option{-P} @var{options}|@option{--private=}@var{options}]
2269 [@option{-r}|@option{--reloc}]
2270 [@option{-R}|@option{--dynamic-reloc}]
2271 [@option{-s}|@option{--full-contents}]
2272 [@option{-W[lLiaprmfFsoORtUuTgAck]}|
2273 @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]]
2274 [@option{-WK}|@option{--dwarf=follow-links}]
2275 [@option{-WN}|@option{--dwarf=no-follow-links}]
2276 [@option{-wD}|@option{--dwarf=use-debuginfod}]
2277 [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
2278 [@option{-L}|@option{--process-links}]
2279 [@option{--ctf=}@var{section}]
2280 [@option{--sframe=}@var{section}]
2281 [@option{-G}|@option{--stabs}]
2282 [@option{-t}|@option{--syms}]
2283 [@option{-T}|@option{--dynamic-syms}]
2284 [@option{-x}|@option{--all-headers}]
2285 [@option{-w}|@option{--wide}]
2286 [@option{--start-address=}@var{address}]
2287 [@option{--stop-address=}@var{address}]
2288 [@option{--no-addresses}]
2289 [@option{--prefix-addresses}]
2290 [@option{--[no-]show-raw-insn}]
2291 [@option{--adjust-vma=}@var{offset}]
2292 [@option{--show-all-symbols}]
2293 [@option{--dwarf-depth=@var{n}}]
2294 [@option{--dwarf-start=@var{n}}]
2295 [@option{--ctf-parent=}@var{section}]
2296 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2297 [@option{--special-syms}]
2298 [@option{--prefix=}@var{prefix}]
2299 [@option{--prefix-strip=}@var{level}]
2300 [@option{--insn-width=}@var{width}]
2301 [@option{--visualize-jumps[=color|=extended-color|=off]}
2302 [@option{--disassembler-color=[off|terminal|on|extended]}
2303 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
2304 [@option{-V}|@option{--version}]
2305 [@option{-H}|@option{--help}]
2306 @var{objfile}@dots{}
2307 @c man end
2308 @end smallexample
2309
2310 @c man begin DESCRIPTION objdump
2311
2312 @command{objdump} displays information about one or more object files.
2313 The options control what particular information to display. This
2314 information is mostly useful to programmers who are working on the
2315 compilation tools, as opposed to programmers who just want their
2316 program to compile and work.
2317
2318 @var{objfile}@dots{} are the object files to be examined. When you
2319 specify archives, @command{objdump} shows information on each of the member
2320 object files.
2321
2322 @c man end
2323
2324 @c man begin OPTIONS objdump
2325
2326 The long and short forms of options, shown here as alternatives, are
2327 equivalent. At least one option from the list
2328 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2329
2330 @table @env
2331 @item -a
2332 @itemx --archive-header
2333 @cindex archive headers
2334 If any of the @var{objfile} files are archives, display the archive
2335 header information (in a format similar to @samp{ls -l}). Besides the
2336 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2337 the object file format of each archive member.
2338
2339 @item --adjust-vma=@var{offset}
2340 @cindex section addresses in objdump
2341 @cindex VMA in objdump
2342 When dumping information, first add @var{offset} to all the section
2343 addresses. This is useful if the section addresses do not correspond to
2344 the symbol table, which can happen when putting sections at particular
2345 addresses when using a format which can not represent section addresses,
2346 such as a.out.
2347
2348 @item -b @var{bfdname}
2349 @itemx --target=@var{bfdname}
2350 @cindex object code format
2351 Specify that the object-code format for the object files is
2352 @var{bfdname}. This option may not be necessary; @var{objdump} can
2353 automatically recognize many formats.
2354
2355 For example,
2356 @example
2357 objdump -b oasys -m vax -h fu.o
2358 @end example
2359 @noindent
2360 displays summary information from the section headers (@option{-h}) of
2361 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2362 file in the format produced by Oasys compilers. You can list the
2363 formats available with the @option{-i} option.
2364 @xref{Target Selection}, for more information.
2365
2366 @item -C
2367 @itemx --demangle[=@var{style}]
2368 @cindex demangling in objdump
2369 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2370 Besides removing any initial underscore prepended by the system, this
2371 makes C++ function names readable. Different compilers have different
2372 mangling styles. The optional demangling style argument can be used to
2373 choose an appropriate demangling style for your compiler. @xref{c++filt},
2374 for more information on demangling.
2375
2376 @item --recurse-limit
2377 @itemx --no-recurse-limit
2378 @itemx --recursion-limit
2379 @itemx --no-recursion-limit
2380 Enables or disables a limit on the amount of recursion performed
2381 whilst demangling strings. Since the name mangling formats allow for
2382 an infinite level of recursion it is possible to create strings whose
2383 decoding will exhaust the amount of stack space available on the host
2384 machine, triggering a memory fault. The limit tries to prevent this
2385 from happening by restricting recursion to 2048 levels of nesting.
2386
2387 The default is for this limit to be enabled, but disabling it may be
2388 necessary in order to demangle truly complicated names. Note however
2389 that if the recursion limit is disabled then stack exhaustion is
2390 possible and any bug reports about such an event will be rejected.
2391
2392 @item -g
2393 @itemx --debugging
2394 Display debugging information. This attempts to parse STABS
2395 debugging format information stored in the file and print it out using
2396 a C like syntax. If no STABS debugging was found this option
2397 falls back on the @option{-W} option to print any DWARF information in
2398 the file.
2399
2400 @item -e
2401 @itemx --debugging-tags
2402 Like @option{-g}, but the information is generated in a format compatible
2403 with ctags tool.
2404
2405 @item -d
2406 @itemx --disassemble
2407 @itemx --disassemble=@var{symbol}
2408 @cindex disassembling object code
2409 @cindex machine instructions
2410 Display the assembler mnemonics for the machine instructions from the
2411 input file. This option only disassembles those sections which are
2412 expected to contain instructions. If the optional @var{symbol}
2413 argument is given, then display the assembler mnemonics starting at
2414 @var{symbol}. If @var{symbol} is a function name then disassembly
2415 will stop at the end of the function, otherwise it will stop when the
2416 next symbol is encountered. If there are no matches for @var{symbol}
2417 then nothing will be displayed.
2418
2419 Note if the @option{--dwarf=follow-links} option is enabled
2420 then any symbol tables in linked debug info files will be read in and
2421 used when disassembling.
2422
2423 @item -D
2424 @itemx --disassemble-all
2425 Like @option{-d}, but disassemble the contents of all non-empty
2426 non-bss sections, not just those expected to contain instructions.
2427 @option{-j} may be used to select specific sections.
2428
2429 This option also has a subtle effect on the disassembly of
2430 instructions in code sections. When option @option{-d} is in effect
2431 objdump will assume that any symbols present in a code section occur
2432 on the boundary between instructions and it will refuse to disassemble
2433 across such a boundary. When option @option{-D} is in effect however
2434 this assumption is supressed. This means that it is possible for the
2435 output of @option{-d} and @option{-D} to differ if, for example, data
2436 is stored in code sections.
2437
2438 If the target is an ARM architecture this switch also has the effect
2439 of forcing the disassembler to decode pieces of data found in code
2440 sections as if they were instructions.
2441
2442 Note if the @option{--dwarf=follow-links} option is enabled
2443 then any symbol tables in linked debug info files will be read in and
2444 used when disassembling.
2445
2446 @item --no-addresses
2447 When disassembling, don't print addresses on each line or for symbols
2448 and relocation offsets. In combination with @option{--no-show-raw-insn}
2449 this may be useful for comparing compiler output.
2450
2451 @item --prefix-addresses
2452 When disassembling, print the complete address on each line. This is
2453 the older disassembly format.
2454
2455 @item -EB
2456 @itemx -EL
2457 @itemx --endian=@{big|little@}
2458 @cindex endianness
2459 @cindex disassembly endianness
2460 Specify the endianness of the object files. This only affects
2461 disassembly. This can be useful when disassembling a file format which
2462 does not describe endianness information, such as S-records.
2463
2464 @item -f
2465 @itemx --file-headers
2466 @cindex object file header
2467 Display summary information from the overall header of
2468 each of the @var{objfile} files.
2469
2470 @item -F
2471 @itemx --file-offsets
2472 @cindex object file offsets
2473 When disassembling sections, whenever a symbol is displayed, also
2474 display the file offset of the region of data that is about to be
2475 dumped. If zeroes are being skipped, then when disassembly resumes,
2476 tell the user how many zeroes were skipped and the file offset of the
2477 location from where the disassembly resumes. When dumping sections,
2478 display the file offset of the location from where the dump starts.
2479
2480 @item --file-start-context
2481 @cindex source code context
2482 Specify that when displaying interlisted source code/disassembly
2483 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2484 context to the start of the file.
2485
2486 @item -h
2487 @itemx --section-headers
2488 @itemx --headers
2489 @cindex section headers
2490 Display summary information from the section headers of the
2491 object file.
2492
2493 File segments may be relocated to nonstandard addresses, for example by
2494 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2495 @command{ld}. However, some object file formats, such as a.out, do not
2496 store the starting address of the file segments. In those situations,
2497 although @command{ld} relocates the sections correctly, using @samp{objdump
2498 -h} to list the file section headers cannot show the correct addresses.
2499 Instead, it shows the usual addresses, which are implicit for the
2500 target.
2501
2502 Note, in some cases it is possible for a section to have both the
2503 READONLY and the NOREAD attributes set. In such cases the NOREAD
2504 attribute takes precedence, but @command{objdump} will report both
2505 since the exact setting of the flag bits might be important.
2506
2507 @item -H
2508 @itemx --help
2509 Print a summary of the options to @command{objdump} and exit.
2510
2511 @item -i
2512 @itemx --info
2513 @cindex architectures available
2514 @cindex object formats available
2515 Display a list showing all architectures and object formats available
2516 for specification with @option{-b} or @option{-m}.
2517
2518 @item -j @var{name}
2519 @itemx --section=@var{name}
2520 @cindex section information
2521 Display information for section @var{name}. This option may be
2522 specified multiple times.
2523
2524 @item -L
2525 @itemx --process-links
2526 Display the contents of non-debug sections found in separate debuginfo
2527 files that are linked to the main file. This option automatically
2528 implies the @option{-WK} option, and only sections requested by other
2529 command line options will be displayed.
2530
2531 @item -l
2532 @itemx --line-numbers
2533 @cindex source filenames for object files
2534 Label the display (using debugging information) with the filename and
2535 source line numbers corresponding to the object code or relocs shown.
2536 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2537
2538 @item -m @var{machine}
2539 @itemx --architecture=@var{machine}
2540 @cindex architecture
2541 @cindex disassembly architecture
2542 Specify the architecture to use when disassembling object files. This
2543 can be useful when disassembling object files which do not describe
2544 architecture information, such as S-records. You can list the available
2545 architectures with the @option{-i} option.
2546
2547 For most architectures it is possible to supply an architecture
2548 name and a machine name, separated by a colon. For example
2549 @samp{foo:bar} would refer to the @samp{bar} machine type in the
2550 @samp{foo} architecture. This can be helpful if objdump has been
2551 configured to support multiple architectures.
2552
2553 If the target is an ARM architecture then this switch has an
2554 additional effect. It restricts the disassembly to only those
2555 instructions supported by the architecture specified by @var{machine}.
2556 If it is necessary to use this switch because the input file does not
2557 contain any architecture information, but it is also desired to
2558 disassemble all the instructions use @option{-marm}.
2559
2560 @item -M @var{options}
2561 @itemx --disassembler-options=@var{options}
2562 Pass target specific information to the disassembler. Only supported on
2563 some targets. If it is necessary to specify more than one
2564 disassembler option then multiple @option{-M} options can be used or
2565 can be placed together into a comma separated list.
2566
2567 For ARC, @option{dsp} controls the printing of DSP instructions,
2568 @option{spfp} selects the printing of FPX single precision FP
2569 instructions, @option{dpfp} selects the printing of FPX double
2570 precision FP instructions, @option{quarkse_em} selects the printing of
2571 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2572 of double precision assist instructions, @option{fpus} selects the
2573 printing of FPU single precision FP instructions, while @option{fpud}
2574 selects the printing of FPU double precision FP instructions.
2575 Additionally, one can choose to have all the immediates printed in
2576 hexadecimal using @option{hex}. By default, the short immediates are
2577 printed using the decimal representation, while the long immediate
2578 values are printed as hexadecimal.
2579
2580 @option{cpu=...} allows one to enforce a particular ISA when disassembling
2581 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2582 This might be useful to select ARC EM or HS ISA, because architecture is same
2583 for those and disassembler relies on private ELF header data to decide if code
2584 is for EM or HS. This option might be specified multiple times - only the
2585 latest value will be used. Valid values are same as for the assembler
2586 @option{-mcpu=...} option.
2587
2588 If the target is an ARM architecture then this switch can be used to
2589 select which register name set is used during disassembler. Specifying
2590 @option{-M reg-names-std} (the default) will select the register names as
2591 used in ARM's instruction set documentation, but with register 13 called
2592 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2593 @option{-M reg-names-apcs} will select the name set used by the ARM
2594 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2595 just use @samp{r} followed by the register number.
2596
2597 There are also two variants on the APCS register naming scheme enabled
2598 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2599 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2600 with the normal register names or the special register names).
2601
2602 This option can also be used for ARM architectures to force the
2603 disassembler to interpret all instructions as Thumb instructions by
2604 using the switch @option{--disassembler-options=force-thumb}. This can be
2605 useful when attempting to disassemble thumb code produced by other
2606 compilers.
2607
2608 For AArch64 targets this switch can be used to set whether instructions are
2609 disassembled as the most general instruction using the @option{-M no-aliases}
2610 option or whether instruction notes should be generated as comments in the
2611 disasssembly using @option{-M notes}.
2612
2613 For the x86, some of the options duplicate functions of the @option{-m}
2614 switch, but allow finer grained control.
2615 @table @code
2616 @item x86-64
2617 @itemx i386
2618 @itemx i8086
2619 Select disassembly for the given architecture.
2620
2621 @item intel
2622 @itemx att
2623 Select between intel syntax mode and AT&T syntax mode.
2624
2625 @item amd64
2626 @itemx intel64
2627 Select between AMD64 ISA and Intel64 ISA.
2628
2629 @item intel-mnemonic
2630 @itemx att-mnemonic
2631 Select between intel mnemonic mode and AT&T mnemonic mode.
2632 Note: @code{intel-mnemonic} implies @code{intel} and
2633 @code{att-mnemonic} implies @code{att}.
2634
2635 @item addr64
2636 @itemx addr32
2637 @itemx addr16
2638 @itemx data32
2639 @itemx data16
2640 Specify the default address size and operand size. These five options
2641 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2642 appear later in the option string.
2643
2644 @item suffix
2645 When in AT&T mode and also for a limited set of instructions when in Intel
2646 mode, instructs the disassembler to print a mnemonic suffix even when the
2647 suffix could be inferred by the operands or, for certain instructions, the
2648 execution mode's defaults.
2649 @end table
2650
2651 For PowerPC, the @option{-M} argument @option{raw} selects
2652 disasssembly of hardware insns rather than aliases. For example, you
2653 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2654 rather than @code{li}. All of the @option{-m} arguments for
2655 @command{gas} that select a CPU are supported. These are:
2656 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2657 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2658 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2659 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2660 @option{booke32}, @option{cell}, @option{com}, @option{e200z2}, @option{e200z4},
2661 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2662 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2663 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2664 @option{power8}, @option{power9}, @option{power10}, @option{ppc},
2665 @option{ppc32}, @option{ppc64}, @option{ppc64bridge}, @option{ppcps},
2666 @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2667 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9}, @option{pwr10},
2668 @option{pwrx}, @option{titan}, @option{vle}, and @option{future}.
2669 @option{32} and @option{64} modify the default or a prior CPU
2670 selection, disabling and enabling 64-bit insns respectively. In
2671 addition, @option{altivec}, @option{any}, @option{lsp}, @option{htm},
2672 @option{vsx}, @option{spe} and @option{spe2} add capabilities to a
2673 previous @emph{or later} CPU selection.
2674 @option{any} will disassemble any opcode known to
2675 binutils, but in cases where an opcode has two different meanings or
2676 different arguments, you may not see the disassembly you expect.
2677 If you disassemble without giving a CPU selection, a default will be
2678 chosen from information gleaned by BFD from the object files headers,
2679 but the result again may not be as you expect.
2680
2681 For MIPS, this option controls the printing of instruction mnemonic
2682 names and register names in disassembled instructions. Multiple
2683 selections from the following may be specified as a comma separated
2684 string, and invalid options are ignored:
2685
2686 @table @code
2687 @item no-aliases
2688 Print the 'raw' instruction mnemonic instead of some pseudo
2689 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2690 'sll' instead of 'nop', etc.
2691
2692 @item msa
2693 Disassemble MSA instructions.
2694
2695 @item virt
2696 Disassemble the virtualization ASE instructions.
2697
2698 @item xpa
2699 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2700
2701 @item gpr-names=@var{ABI}
2702 Print GPR (general-purpose register) names as appropriate
2703 for the specified ABI. By default, GPR names are selected according to
2704 the ABI of the binary being disassembled.
2705
2706 @item fpr-names=@var{ABI}
2707 Print FPR (floating-point register) names as
2708 appropriate for the specified ABI. By default, FPR numbers are printed
2709 rather than names.
2710
2711 @item cp0-names=@var{ARCH}
2712 Print CP0 (system control coprocessor; coprocessor 0) register names
2713 as appropriate for the CPU or architecture specified by
2714 @var{ARCH}. By default, CP0 register names are selected according to
2715 the architecture and CPU of the binary being disassembled.
2716
2717 @item hwr-names=@var{ARCH}
2718 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2719 as appropriate for the CPU or architecture specified by
2720 @var{ARCH}. By default, HWR names are selected according to
2721 the architecture and CPU of the binary being disassembled.
2722
2723 @item reg-names=@var{ABI}
2724 Print GPR and FPR names as appropriate for the selected ABI.
2725
2726 @item reg-names=@var{ARCH}
2727 Print CPU-specific register names (CP0 register and HWR names)
2728 as appropriate for the selected CPU or architecture.
2729 @end table
2730
2731 For any of the options listed above, @var{ABI} or
2732 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2733 rather than names, for the selected types of registers.
2734 You can list the available values of @var{ABI} and @var{ARCH} using
2735 the @option{--help} option.
2736
2737 For VAX, you can specify function entry addresses with @option{-M
2738 entry:0xf00ba}. You can use this multiple times to properly
2739 disassemble VAX binary files that don't contain symbol tables (like
2740 ROM dumps). In these cases, the function entry mask would otherwise
2741 be decoded as VAX instructions, which would probably lead the rest
2742 of the function being wrongly disassembled.
2743
2744 @item -p
2745 @itemx --private-headers
2746 Print information that is specific to the object file format. The exact
2747 information printed depends upon the object file format. For some
2748 object file formats, no additional information is printed.
2749
2750 @item -P @var{options}
2751 @itemx --private=@var{options}
2752 Print information that is specific to the object file format. The
2753 argument @var{options} is a comma separated list that depends on the
2754 format (the lists of options is displayed with the help).
2755
2756 For XCOFF, the available options are:
2757 @table @code
2758 @item header
2759 @item aout
2760 @item sections
2761 @item syms
2762 @item relocs
2763 @item lineno,
2764 @item loader
2765 @item except
2766 @item typchk
2767 @item traceback
2768 @item toc
2769 @item ldinfo
2770 @end table
2771
2772 For PE, the available options are:
2773 @table @code
2774 @item header
2775 @item sections
2776 @end table
2777
2778 Not all object formats support this option. In particular the ELF
2779 format does not use it.
2780
2781 @item -r
2782 @itemx --reloc
2783 @cindex relocation entries, in object file
2784 Print the relocation entries of the file. If used with @option{-d} or
2785 @option{-D}, the relocations are printed interspersed with the
2786 disassembly.
2787
2788 @item -R
2789 @itemx --dynamic-reloc
2790 @cindex dynamic relocation entries, in object file
2791 Print the dynamic relocation entries of the file. This is only
2792 meaningful for dynamic objects, such as certain types of shared
2793 libraries. As for @option{-r}, if used with @option{-d} or
2794 @option{-D}, the relocations are printed interspersed with the
2795 disassembly.
2796
2797 @item -s
2798 @itemx --full-contents
2799 @cindex sections, full contents
2800 @cindex object file sections
2801 Display the full contents of sections, often used in combination with
2802 @option{-j} to request specific sections. By default all non-empty
2803 non-bss sections are displayed.
2804
2805 @item -S
2806 @itemx --source
2807 @cindex source disassembly
2808 @cindex disassembly, with source
2809 Display source code intermixed with disassembly, if possible. Implies
2810 @option{-d}.
2811
2812 @item --show-all-symbols
2813 When disassembling, show all the symbols that match a given address,
2814 not just the first one.
2815
2816 @item --source-comment[=@var{txt}]
2817 @cindex source disassembly
2818 @cindex disassembly, with source
2819 Like the @option{-S} option, but all source code lines are displayed
2820 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2821 string which can be used to distinguish the assembler code from the
2822 source code. If @var{txt} is not provided then a default string of
2823 @var{``# ``} (hash followed by a space), will be used.
2824
2825 @item --prefix=@var{prefix}
2826 @cindex Add prefix to absolute paths
2827 Specify @var{prefix} to add to the absolute paths when used with
2828 @option{-S}.
2829
2830 @item --prefix-strip=@var{level}
2831 @cindex Strip absolute paths
2832 Indicate how many initial directory names to strip off the hardwired
2833 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2834
2835 @item --show-raw-insn
2836 When disassembling instructions, print the instruction in hex as well as
2837 in symbolic form. This is the default except when
2838 @option{--prefix-addresses} is used.
2839
2840 @item --no-show-raw-insn
2841 When disassembling instructions, do not print the instruction bytes.
2842 This is the default when @option{--prefix-addresses} is used.
2843
2844 @item --insn-width=@var{width}
2845 @cindex Instruction width
2846 Display @var{width} bytes on a single line when disassembling
2847 instructions.
2848
2849 @item --visualize-jumps[=color|=extended-color|=off]
2850 Visualize jumps that stay inside a function by drawing ASCII art between
2851 the start and target addresses. The optional @option{=color} argument
2852 adds color to the output using simple terminal colors. Alternatively
2853 the @option{=extended-color} argument will add color using 8bit
2854 colors, but these might not work on all terminals.
2855
2856 If it is necessary to disable the @option{visualize-jumps} option
2857 after it has previously been enabled then use
2858 @option{visualize-jumps=off}.
2859
2860 @item --disassembler-color=off
2861 @itemx --disassembler-color=terminal
2862 @itemx --disassembler-color=on|color|colour
2863 @itemx --disassembler-color=extened|extended-color|extened-colour
2864 Enables or disables the use of colored syntax highlighting in
2865 disassembly output. The default behaviour is determined via a
2866 configure time option. Note, not all architectures support colored
2867 syntax highlighting, and depending upon the terminal used, colored
2868 output may not actually be legible.
2869
2870 The @option{on} argument adds colors using simple terminal colors.
2871
2872 The @option{terminal} argument does the same, but only if the output
2873 device is a terminal.
2874
2875 The @option{extended-color} argument is similar to the @option{on}
2876 argument, but it uses 8-bit colors. These may not work on all
2877 terminals.
2878
2879 The @option{off} argument disables colored disassembly.
2880
2881 @item -W[lLiaprmfFsoORtUuTgAckK]
2882 @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]
2883 @include debug.options.texi
2884
2885 @item --dwarf-check
2886 Enable additional checks for consistency of Dwarf information.
2887
2888 @include ctf.options.texi
2889
2890 @include sframe.options.texi
2891
2892 @item -G
2893 @itemx --stabs
2894 @cindex stab
2895 @cindex .stab
2896 @cindex debug symbols
2897 @cindex ELF object file format
2898 Display the full contents of any sections requested. Display the
2899 contents of the .stab and .stab.index and .stab.excl sections from an
2900 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2901 @code{.stab} debugging symbol-table entries are carried in an ELF
2902 section. In most other file formats, debugging symbol-table entries are
2903 interleaved with linkage symbols, and are visible in the @option{--syms}
2904 output.
2905
2906 @item --start-address=@var{address}
2907 @cindex start-address
2908 Start displaying data at the specified address. This affects the output
2909 of the @option{-d}, @option{-r} and @option{-s} options.
2910
2911 @item --stop-address=@var{address}
2912 @cindex stop-address
2913 Stop displaying data at the specified address. This affects the output
2914 of the @option{-d}, @option{-r} and @option{-s} options.
2915
2916 @item -t
2917 @itemx --syms
2918 @cindex symbol table entries, printing
2919 Print the symbol table entries of the file.
2920 This is similar to the information provided by the @samp{nm} program,
2921 although the display format is different. The format of the output
2922 depends upon the format of the file being dumped, but there are two main
2923 types. One looks like this:
2924
2925 @smallexample
2926 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2927 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2928 @end smallexample
2929
2930 where the number inside the square brackets is the number of the entry
2931 in the symbol table, the @var{sec} number is the section number, the
2932 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2933 symbol's type, the @var{scl} number is the symbol's storage class and
2934 the @var{nx} value is the number of auxiliary entries associated with
2935 the symbol. The last two fields are the symbol's value and its name.
2936
2937 The other common output format, usually seen with ELF based files,
2938 looks like this:
2939
2940 @smallexample
2941 00000000 l d .bss 00000000 .bss
2942 00000000 g .text 00000000 fred
2943 @end smallexample
2944
2945 Here the first number is the symbol's value (sometimes referred to as
2946 its address). The next field is actually a set of characters and
2947 spaces indicating the flag bits that are set on the symbol. These
2948 characters are described below. Next is the section with which the
2949 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2950 not connected with any section), or @emph{*UND*} if the section is
2951 referenced in the file being dumped, but not defined there.
2952
2953 After the section name comes another field, a number, which for common
2954 symbols is the alignment and for other symbol is the size. Finally
2955 the symbol's name is displayed.
2956
2957 The flag characters are divided into 7 groups as follows:
2958 @table @code
2959 @item l
2960 @itemx g
2961 @itemx u
2962 @itemx !
2963 The symbol is a local (l), global (g), unique global (u), neither
2964 global nor local (a space) or both global and local (!). A
2965 symbol can be neither local or global for a variety of reasons, e.g.,
2966 because it is used for debugging, but it is probably an indication of
2967 a bug if it is ever both local and global. Unique global symbols are
2968 a GNU extension to the standard set of ELF symbol bindings. For such
2969 a symbol the dynamic linker will make sure that in the entire process
2970 there is just one symbol with this name and type in use.
2971
2972 @item w
2973 The symbol is weak (w) or strong (a space).
2974
2975 @item C
2976 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2977
2978 @item W
2979 The symbol is a warning (W) or a normal symbol (a space). A warning
2980 symbol's name is a message to be displayed if the symbol following the
2981 warning symbol is ever referenced.
2982
2983 @item I
2984 @item i
2985 The symbol is an indirect reference to another symbol (I), a function
2986 to be evaluated during reloc processing (i) or a normal symbol (a
2987 space).
2988
2989 @item d
2990 @itemx D
2991 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2992 normal symbol (a space).
2993
2994 @item F
2995 @item f
2996 @item O
2997 The symbol is the name of a function (F) or a file (f) or an object
2998 (O) or just a normal symbol (a space).
2999 @end table
3000
3001 @item -T
3002 @itemx --dynamic-syms
3003 @cindex dynamic symbol table entries, printing
3004 Print the dynamic symbol table entries of the file. This is only
3005 meaningful for dynamic objects, such as certain types of shared
3006 libraries. This is similar to the information provided by the @samp{nm}
3007 program when given the @option{-D} (@option{--dynamic}) option.
3008
3009 The output format is similar to that produced by the @option{--syms}
3010 option, except that an extra field is inserted before the symbol's
3011 name, giving the version information associated with the symbol.
3012 If the version is the default version to be used when resolving
3013 unversioned references to the symbol then it's displayed as is,
3014 otherwise it's put into parentheses.
3015
3016 @item --special-syms
3017 When displaying symbols include those which the target considers to be
3018 special in some way and which would not normally be of interest to the
3019 user.
3020
3021 @item -U @var{[d|i|l|e|x|h]}
3022 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3023 Controls the display of UTF-8 encoded multibyte characters in strings.
3024 The default (@option{--unicode=default}) is to give them no special
3025 treatment. The @option{--unicode=locale} option displays the sequence
3026 in the current locale, which may or may not support them. The options
3027 @option{--unicode=hex} and @option{--unicode=invalid} display them as
3028 hex byte sequences enclosed by either angle brackets or curly braces.
3029
3030 The @option{--unicode=escape} option displays them as escape sequences
3031 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
3032 them as escape sequences highlighted in red (if supported by the
3033 output device). The colouring is intended to draw attention to the
3034 presence of unicode sequences where they might not be expected.
3035
3036 @item -V
3037 @itemx --version
3038 Print the version number of @command{objdump} and exit.
3039
3040 @item -x
3041 @itemx --all-headers
3042 @cindex all header information, object file
3043 @cindex header information, all
3044 Display all available header information, including the symbol table and
3045 relocation entries. Using @option{-x} is equivalent to specifying all of
3046 @option{-a -f -h -p -r -t}.
3047
3048 @item -w
3049 @itemx --wide
3050 @cindex wide output, printing
3051 Format some lines for output devices that have more than 80 columns.
3052 Also do not truncate symbol names when they are displayed.
3053
3054 @item -z
3055 @itemx --disassemble-zeroes
3056 Normally the disassembly output will skip blocks of zeroes. This
3057 option directs the disassembler to disassemble those blocks, just like
3058 any other data.
3059 @end table
3060
3061 @c man end
3062
3063 @ignore
3064 @c man begin SEEALSO objdump
3065 nm(1), readelf(1), and the Info entries for @file{binutils}.
3066 @c man end
3067 @end ignore
3068
3069 @node ranlib
3070 @chapter ranlib
3071
3072 @kindex ranlib
3073 @cindex archive contents
3074 @cindex symbol index
3075
3076 @c man title ranlib generate an index to an archive
3077
3078 @smallexample
3079 @c man begin SYNOPSIS ranlib
3080 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
3081 @c man end
3082 @end smallexample
3083
3084 @c man begin DESCRIPTION ranlib
3085
3086 @command{ranlib} generates an index to the contents of an archive and
3087 stores it in the archive. The index lists each symbol defined by a
3088 member of an archive that is a relocatable object file.
3089
3090 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
3091
3092 An archive with such an index speeds up linking to the library and
3093 allows routines in the library to call each other without regard to
3094 their placement in the archive.
3095
3096 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
3097 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
3098 @xref{ar}.
3099
3100 @c man end
3101
3102 @c man begin OPTIONS ranlib
3103
3104 @table @env
3105 @item -h
3106 @itemx -H
3107 @itemx --help
3108 Show usage information for @command{ranlib}.
3109
3110 @item -v
3111 @itemx -V
3112 @itemx --version
3113 Show the version number of @command{ranlib}.
3114
3115 @item -D
3116 @cindex deterministic archives
3117 @kindex --enable-deterministic-archives
3118 Operate in @emph{deterministic} mode. The symbol map archive member's
3119 header will show zero for the UID, GID, and timestamp. When this
3120 option is used, multiple runs will produce identical output files.
3121
3122 If @file{binutils} was configured with
3123 @option{--enable-deterministic-archives}, then this mode is on by
3124 default. It can be disabled with the @samp{-U} option, described
3125 below.
3126
3127 @item -t
3128 Update the timestamp of the symbol map of an archive.
3129
3130 @item -U
3131 @cindex deterministic archives
3132 @kindex --enable-deterministic-archives
3133 Do @emph{not} operate in @emph{deterministic} mode. This is the
3134 inverse of the @samp{-D} option, above: the archive index will get
3135 actual UID, GID, timestamp, and file mode values.
3136
3137 If @file{binutils} was configured @emph{without}
3138 @option{--enable-deterministic-archives}, then this mode is on by
3139 default.
3140
3141 @end table
3142
3143 @c man end
3144
3145 @ignore
3146 @c man begin SEEALSO ranlib
3147 ar(1), nm(1), and the Info entries for @file{binutils}.
3148 @c man end
3149 @end ignore
3150
3151 @node size
3152 @chapter size
3153
3154 @kindex size
3155 @cindex section sizes
3156
3157 @c man title size list section sizes and total size of binary files
3158
3159 @smallexample
3160 @c man begin SYNOPSIS size
3161 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
3162 [@option{--help}]
3163 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
3164 [@option{--common}]
3165 [@option{-t}|@option{--totals}]
3166 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
3167 [@option{-f}]
3168 [@var{objfile}@dots{}]
3169 @c man end
3170 @end smallexample
3171
3172 @c man begin DESCRIPTION size
3173
3174 The @sc{gnu} @command{size} utility lists the section sizes and the total
3175 size for each of the binary files @var{objfile} on its argument list.
3176 By default, one line of output is generated for each file or each
3177 module if the file is an archive.
3178
3179 @var{objfile}@dots{} are the files to be examined. If none are
3180 specified, the file @code{a.out} will be used instead.
3181
3182 @c man end
3183
3184 @c man begin OPTIONS size
3185
3186 The command-line options have the following meanings:
3187
3188 @table @env
3189 @item -A
3190 @itemx -B
3191 @itemx -G
3192 @itemx --format=@var{compatibility}
3193 @cindex @command{size} display format
3194 Using one of these options, you can choose whether the output from @sc{gnu}
3195 @command{size} resembles output from System V @command{size} (using @option{-A},
3196 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3197 @option{--format=berkeley}). The default is the one-line format similar to
3198 Berkeley's. Alternatively, you can choose the GNU format output
3199 (using @option{-G}, or @option{--format=gnu}), this is similar to
3200 Berkeley's output format, but sizes are counted differently.
3201 @c Bonus for doc-source readers: you can also say --format=strange (or
3202 @c anything else that starts with 's') for sysv, and --format=boring (or
3203 @c anything else that starts with 'b') for Berkeley.
3204
3205 Here is an example of the Berkeley (default) format of output from
3206 @command{size}:
3207 @smallexample
3208 $ size --format=Berkeley ranlib size
3209 text data bss dec hex filename
3210 294880 81920 11592 388392 5ed28 ranlib
3211 294880 81920 11888 388688 5ee50 size
3212 @end smallexample
3213
3214 The Berkeley style output counts read only data in the @code{text}
3215 column, not in the @code{data} column, the @code{dec} and @code{hex}
3216 columns both display the sum of the @code{text}, @code{data}, and
3217 @code{bss} columns in decimal and hexadecimal respectively.
3218
3219 The GNU format counts read only data in the @code{data} column, not
3220 the @code{text} column, and only displays the sum of the @code{text},
3221 @code{data}, and @code{bss} columns once, in the @code{total} column.
3222 The @option{--radix} option can be used to change the number base for
3223 all columns. Here is the same data displayed with GNU conventions:
3224
3225 @smallexample
3226 $ size --format=GNU ranlib size
3227 text data bss total filename
3228 279880 96920 11592 388392 ranlib
3229 279880 96920 11888 388688 size
3230 @end smallexample
3231
3232 @noindent
3233 This is the same data, but displayed closer to System V conventions:
3234
3235 @smallexample
3236 $ size --format=SysV ranlib size
3237 ranlib :
3238 section size addr
3239 .text 294880 8192
3240 .data 81920 303104
3241 .bss 11592 385024
3242 Total 388392
3243
3244
3245 size :
3246 section size addr
3247 .text 294880 8192
3248 .data 81920 303104
3249 .bss 11888 385024
3250 Total 388688
3251 @end smallexample
3252
3253 @item --help
3254 @itemx -h
3255 @itemx -H
3256 @item -?
3257 Show a summary of acceptable arguments and options.
3258
3259 @item -d
3260 @itemx -o
3261 @itemx -x
3262 @itemx --radix=@var{number}
3263 @cindex @command{size} number format
3264 @cindex radix for section sizes
3265 Using one of these options, you can control whether the size of each
3266 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3267 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3268 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3269 values (8, 10, 16) are supported. The total size is always given in two
3270 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3271 octal and hexadecimal if you're using @option{-o}.
3272
3273 @item --common
3274 Print total size of common symbols in each file. When using Berkeley
3275 or GNU format these are included in the bss size.
3276
3277 @item -t
3278 @itemx --totals
3279 Show totals of all objects listed (Berkeley or GNU format mode only).
3280
3281 @item --target=@var{bfdname}
3282 @cindex object code format
3283 Specify that the object-code format for @var{objfile} is
3284 @var{bfdname}. This option may not be necessary; @command{size} can
3285 automatically recognize many formats.
3286 @xref{Target Selection}, for more information.
3287
3288 @item -v
3289 @item -V
3290 @itemx --version
3291 Display the version number of @command{size}.
3292
3293 @item -f
3294 Ignored. This option is used by other versions of the @command{size}
3295 program, but it is not supported by the GNU Binutils version.
3296
3297 @end table
3298
3299 @c man end
3300
3301 @ignore
3302 @c man begin SEEALSO size
3303 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3304 @c man end
3305 @end ignore
3306
3307 @node strings
3308 @chapter strings
3309 @kindex strings
3310 @cindex listings strings
3311 @cindex printing strings
3312 @cindex strings, printing
3313
3314 @c man title strings print the sequences of printable characters in files
3315
3316 @smallexample
3317 @c man begin SYNOPSIS strings
3318 strings [@option{-afovV}] [@option{-}@var{min-len}]
3319 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3320 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3321 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3322 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
3323 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3324 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3325 [@option{-w}] [@option{--include-all-whitespace}]
3326 [@option{-s}] [@option{--output-separator} @var{sep_string}]
3327 [@option{--help}] [@option{--version}] @var{file}@dots{}
3328 @c man end
3329 @end smallexample
3330
3331 @c man begin DESCRIPTION strings
3332
3333 For each @var{file} given, @sc{gnu} @command{strings} prints the
3334 printable character sequences that are at least 4 characters long (or
3335 the number given with the options below) and are followed by an
3336 unprintable character.
3337
3338 Depending upon how the strings program was configured it will default
3339 to either displaying all the printable sequences that it can find in
3340 each file, or only those sequences that are in loadable, initialized
3341 data sections. If the file type is unrecognizable, or if strings is
3342 reading from stdin then it will always display all of the printable
3343 sequences that it can find.
3344
3345 For backwards compatibility any file that occurs after a command-line
3346 option of just @option{-} will also be scanned in full, regardless of
3347 the presence of any @option{-d} option.
3348
3349 @command{strings} is mainly useful for determining the contents of
3350 non-text files.
3351
3352 @c man end
3353
3354 @c man begin OPTIONS strings
3355
3356 @table @env
3357 @item -a
3358 @itemx --all
3359 @itemx -
3360 Scan the whole file, regardless of what sections it contains or
3361 whether those sections are loaded or initialized. Normally this is
3362 the default behaviour, but strings can be configured so that the
3363 @option{-d} is the default instead.
3364
3365 The @option{-} option is position dependent and forces strings to
3366 perform full scans of any file that is mentioned after the @option{-}
3367 on the command line, even if the @option{-d} option has been
3368 specified.
3369
3370 @item -d
3371 @itemx --data
3372 Only print strings from initialized, loaded data sections in the
3373 file. This may reduce the amount of garbage in the output, but it
3374 also exposes the strings program to any security flaws that may be
3375 present in the BFD library used to scan and load sections. Strings
3376 can be configured so that this option is the default behaviour. In
3377 such cases the @option{-a} option can be used to avoid using the BFD
3378 library and instead just print all of the strings found in the file.
3379
3380 @item -f
3381 @itemx --print-file-name
3382 Print the name of the file before each string.
3383
3384 @item --help
3385 Print a summary of the program usage on the standard output and exit.
3386
3387 @item -@var{min-len}
3388 @itemx -n @var{min-len}
3389 @itemx --bytes=@var{min-len}
3390 Print sequences of displayable characters that are at least
3391 @var{min-len} characters long. If not specified a default minimum
3392 length of 4 is used. The distinction between displayable and
3393 non-displayable characters depends upon the setting of the
3394 @option{-e} and @option{-U} options. Sequences are always terminated
3395 at control characters such as new-line and carriage-return, but not
3396 the tab character.
3397
3398 @item -o
3399 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3400 act like @samp{-t d} instead. Since we can not be compatible with both
3401 ways, we simply chose one.
3402
3403 @item -t @var{radix}
3404 @itemx --radix=@var{radix}
3405 Print the offset within the file before each string. The single
3406 character argument specifies the radix of the offset---@samp{o} for
3407 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3408
3409 @item -e @var{encoding}
3410 @itemx --encoding=@var{encoding}
3411 Select the character encoding of the strings that are to be found.
3412 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3413 characters (default), @samp{S} =
3414 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3415 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3416 littleendian. Useful for finding wide character strings. (@samp{l}
3417 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3418
3419 @item -U @var{[d|i|l|e|x|h]}
3420 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3421 Controls the display of UTF-8 encoded multibyte characters in strings.
3422 The default (@option{--unicode=default}) is to give them no special
3423 treatment, and instead rely upon the setting of the
3424 @option{--encoding} option. The other values for this option
3425 automatically enable @option{--encoding=S}.
3426
3427 The @option{--unicode=invalid} option treats them as non-graphic
3428 characters and hence not part of a valid string. All the remaining
3429 options treat them as valid string characters.
3430
3431 The @option{--unicode=locale} option displays them in the current
3432 locale, which may or may not support UTF-8 encoding. The
3433 @option{--unicode=hex} option displays them as hex byte sequences
3434 enclosed between @var{<>} characters. The @option{--unicode=escape}
3435 option displays them as escape sequences (@var{\uxxxx}) and the
3436 @option{--unicode=highlight} option displays them as escape sequences
3437 highlighted in red (if supported by the output device). The colouring
3438 is intended to draw attention to the presence of unicode sequences
3439 where they might not be expected.
3440
3441 @item -T @var{bfdname}
3442 @itemx --target=@var{bfdname}
3443 @cindex object code format
3444 Specify an object code format other than your system's default format.
3445 @xref{Target Selection}, for more information.
3446
3447 @item -v
3448 @itemx -V
3449 @itemx --version
3450 Print the program version number on the standard output and exit.
3451
3452 @item -w
3453 @itemx --include-all-whitespace
3454 By default tab and space characters are included in the strings that
3455 are displayed, but other whitespace characters, such a newlines and
3456 carriage returns, are not. The @option{-w} option changes this so
3457 that all whitespace characters are considered to be part of a string.
3458
3459 @item -s
3460 @itemx --output-separator
3461 By default, output strings are delimited by a new-line. This option
3462 allows you to supply any string to be used as the output record
3463 separator. Useful with --include-all-whitespace where strings
3464 may contain new-lines internally.
3465 @end table
3466
3467 @c man end
3468
3469 @ignore
3470 @c man begin SEEALSO strings
3471 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3472 and the Info entries for @file{binutils}.
3473 @c man end
3474 @end ignore
3475
3476 @node strip
3477 @chapter strip
3478
3479 @kindex strip
3480 @cindex removing symbols
3481 @cindex discarding symbols
3482 @cindex symbols, discarding
3483
3484 @c man title strip discard symbols and other data from object files
3485
3486 @smallexample
3487 @c man begin SYNOPSIS strip
3488 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3489 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3490 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3491 [@option{-s}|@option{--strip-all}]
3492 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3493 [@option{--strip-dwo}]
3494 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3495 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3496 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3497 [@option{-w}|@option{--wildcard}]
3498 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3499 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3500 [@option{--keep-section=}@var{sectionpattern}]
3501 [@option{--remove-relocations=}@var{sectionpattern}]
3502 [@option{--strip-section-headers}]
3503 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3504 [@option{-D}|@option{--enable-deterministic-archives}]
3505 [@option{-U}|@option{--disable-deterministic-archives}]
3506 [@option{--keep-section-symbols}]
3507 [@option{--keep-file-symbols}]
3508 [@option{--only-keep-debug}]
3509 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3510 [@option{--help}] [@option{--info}]
3511 @var{objfile}@dots{}
3512 @c man end
3513 @end smallexample
3514
3515 @c man begin DESCRIPTION strip
3516
3517 @sc{gnu} @command{strip} discards all symbols from object files
3518 @var{objfile}. The list of object files may include archives.
3519 At least one object file must be given.
3520
3521 @command{strip} modifies the files named in its argument,
3522 rather than writing modified copies under different names.
3523
3524 @c man end
3525
3526 @c man begin OPTIONS strip
3527
3528 @table @env
3529 @item -F @var{bfdname}
3530 @itemx --target=@var{bfdname}
3531 Treat the original @var{objfile} as a file with the object
3532 code format @var{bfdname}, and rewrite it in the same format.
3533 @xref{Target Selection}, for more information.
3534
3535 @item --help
3536 Show a summary of the options to @command{strip} and exit.
3537
3538 @item --info
3539 Display a list showing all architectures and object formats available.
3540
3541 @item -I @var{bfdname}
3542 @itemx --input-target=@var{bfdname}
3543 Treat the original @var{objfile} as a file with the object
3544 code format @var{bfdname}.
3545 @xref{Target Selection}, for more information.
3546
3547 @item -O @var{bfdname}
3548 @itemx --output-target=@var{bfdname}
3549 Replace @var{objfile} with a file in the output format @var{bfdname}.
3550 @xref{Target Selection}, for more information.
3551
3552 @item -R @var{sectionname}
3553 @itemx --remove-section=@var{sectionname}
3554 Remove any section named @var{sectionname} from the output file, in
3555 addition to whatever sections would otherwise be removed. This
3556 option may be given more than once. Note that using this option
3557 inappropriately may make the output file unusable. The wildcard
3558 character @samp{*} may be given at the end of @var{sectionname}. If
3559 so, then any section starting with @var{sectionname} will be removed.
3560
3561 If the first character of @var{sectionpattern} is the exclamation
3562 point (!) then matching sections will not be removed even if an
3563 earlier use of @option{--remove-section} on the same command line
3564 would otherwise remove it. For example:
3565
3566 @smallexample
3567 --remove-section=.text.* --remove-section=!.text.foo
3568 @end smallexample
3569
3570 will remove all sections matching the pattern '.text.*', but will not
3571 remove the section '.text.foo'.
3572
3573 @item --keep-section=@var{sectionpattern}
3574 When removing sections from the output file, keep sections that match
3575 @var{sectionpattern}.
3576
3577 @item --remove-relocations=@var{sectionpattern}
3578 Remove relocations from the output file for any section matching
3579 @var{sectionpattern}. This option may be given more than once. Note
3580 that using this option inappropriately may make the output file
3581 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3582 For example:
3583
3584 @smallexample
3585 --remove-relocations=.text.*
3586 @end smallexample
3587
3588 will remove the relocations for all sections matching the patter
3589 '.text.*'.
3590
3591 If the first character of @var{sectionpattern} is the exclamation
3592 point (!) then matching sections will not have their relocation
3593 removed even if an earlier use of @option{--remove-relocations} on the
3594 same command line would otherwise cause the relocations to be removed.
3595 For example:
3596
3597 @smallexample
3598 --remove-relocations=.text.* --remove-relocations=!.text.foo
3599 @end smallexample
3600
3601 will remove all relocations for sections matching the pattern
3602 '.text.*', but will not remove relocations for the section
3603 '.text.foo'.
3604
3605 @item --strip-section-headers
3606 Strip section headers. This option is specific to ELF files. Implies
3607 @option{--strip-all} and @option{--merge-notes}.
3608
3609 @item -s
3610 @itemx --strip-all
3611 Remove all symbols.
3612
3613 @item -g
3614 @itemx -S
3615 @itemx -d
3616 @itemx --strip-debug
3617 Remove debugging symbols only.
3618
3619 @item --strip-dwo
3620 Remove the contents of all DWARF .dwo sections, leaving the
3621 remaining debugging sections and all symbols intact.
3622 See the description of this option in the @command{objcopy} section
3623 for more information.
3624
3625 @item --strip-unneeded
3626 Remove all symbols that are not needed for relocation processing in
3627 addition to debugging symbols and sections stripped by
3628 @option{--strip-debug}.
3629
3630 @item -K @var{symbolname}
3631 @itemx --keep-symbol=@var{symbolname}
3632 When stripping symbols, keep symbol @var{symbolname} even if it would
3633 normally be stripped. This option may be given more than once.
3634
3635 @item -M
3636 @itemx --merge-notes
3637 @itemx --no-merge-notes
3638 For ELF files, attempt (or do not attempt) to reduce the size of any
3639 SHT_NOTE type sections by removing duplicate notes. The default is to
3640 attempt this reduction unless stripping debug or DWO information.
3641
3642 @item -N @var{symbolname}
3643 @itemx --strip-symbol=@var{symbolname}
3644 Remove symbol @var{symbolname} from the source file. This option may be
3645 given more than once, and may be combined with strip options other than
3646 @option{-K}.
3647
3648 @item -o @var{file}
3649 Put the stripped output in @var{file}, rather than replacing the
3650 existing file. When this argument is used, only one @var{objfile}
3651 argument may be specified.
3652
3653 @item -p
3654 @itemx --preserve-dates
3655 Preserve the access and modification dates of the file.
3656
3657 @item -D
3658 @itemx --enable-deterministic-archives
3659 @cindex deterministic archives
3660 @kindex --enable-deterministic-archives
3661 Operate in @emph{deterministic} mode. When copying archive members
3662 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3663 and use consistent file modes for all files.
3664
3665 If @file{binutils} was configured with
3666 @option{--enable-deterministic-archives}, then this mode is on by default.
3667 It can be disabled with the @samp{-U} option, below.
3668
3669 @item -U
3670 @itemx --disable-deterministic-archives
3671 @cindex deterministic archives
3672 @kindex --enable-deterministic-archives
3673 Do @emph{not} operate in @emph{deterministic} mode. This is the
3674 inverse of the @option{-D} option, above: when copying archive members
3675 and writing the archive index, use their actual UID, GID, timestamp,
3676 and file mode values.
3677
3678 This is the default unless @file{binutils} was configured with
3679 @option{--enable-deterministic-archives}.
3680
3681 @item -w
3682 @itemx --wildcard
3683 Permit regular expressions in @var{symbolname}s used in other command
3684 line options. The question mark (?), asterisk (*), backslash (\) and
3685 square brackets ([]) operators can be used anywhere in the symbol
3686 name. If the first character of the symbol name is the exclamation
3687 point (!) then the sense of the switch is reversed for that symbol.
3688 For example:
3689
3690 @smallexample
3691 -w -K !foo -K fo*
3692 @end smallexample
3693
3694 would cause strip to only keep symbols that start with the letters
3695 ``fo'', but to discard the symbol ``foo''.
3696
3697 @item -x
3698 @itemx --discard-all
3699 Remove non-global symbols.
3700
3701 @item -X
3702 @itemx --discard-locals
3703 Remove compiler-generated local symbols.
3704 (These usually start with @samp{L} or @samp{.}.)
3705
3706 @item --keep-section-symbols
3707 When stripping a file, perhaps with @option{--strip-debug} or
3708 @option{--strip-unneeded}, retain any symbols specifying section names,
3709 which would otherwise get stripped.
3710
3711 @item --keep-file-symbols
3712 When stripping a file, perhaps with @option{--strip-debug} or
3713 @option{--strip-unneeded}, retain any symbols specifying source file names,
3714 which would otherwise get stripped.
3715
3716 @item --only-keep-debug
3717 Strip a file, emptying the contents of any sections that would not be
3718 stripped by @option{--strip-debug} and leaving the debugging sections
3719 intact. In ELF files, this preserves all the note sections in the
3720 output as well.
3721
3722 Note - the section headers of the stripped sections are preserved,
3723 including their sizes, but the contents of the section are discarded.
3724 The section headers are preserved so that other tools can match up the
3725 debuginfo file with the real executable, even if that executable has
3726 been relocated to a different address space.
3727
3728 The intention is that this option will be used in conjunction with
3729 @option{--add-gnu-debuglink} to create a two part executable. One a
3730 stripped binary which will occupy less space in RAM and in a
3731 distribution and the second a debugging information file which is only
3732 needed if debugging abilities are required. The suggested procedure
3733 to create these files is as follows:
3734
3735 @enumerate
3736 @item Link the executable as normal. Assuming that it is called
3737 @code{foo} then...
3738 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3739 create a file containing the debugging info.
3740 @item Run @code{objcopy --strip-debug foo} to create a
3741 stripped executable.
3742 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3743 to add a link to the debugging info into the stripped executable.
3744 @end enumerate
3745
3746 Note---the choice of @code{.dbg} as an extension for the debug info
3747 file is arbitrary. Also the @code{--only-keep-debug} step is
3748 optional. You could instead do this:
3749
3750 @enumerate
3751 @item Link the executable as normal.
3752 @item Copy @code{foo} to @code{foo.full}
3753 @item Run @code{strip --strip-debug foo}
3754 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3755 @end enumerate
3756
3757 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3758 full executable. It does not have to be a file created by the
3759 @option{--only-keep-debug} switch.
3760
3761 Note---this switch is only intended for use on fully linked files. It
3762 does not make sense to use it on object files where the debugging
3763 information may be incomplete. Besides the gnu_debuglink feature
3764 currently only supports the presence of one filename containing
3765 debugging information, not multiple filenames on a one-per-object-file
3766 basis.
3767
3768 @item -V
3769 @itemx --version
3770 Show the version number for @command{strip}.
3771
3772 @item -v
3773 @itemx --verbose
3774 Verbose output: list all object files modified. In the case of
3775 archives, @samp{strip -v} lists all members of the archive.
3776 @end table
3777
3778 @c man end
3779
3780 @ignore
3781 @c man begin SEEALSO strip
3782 the Info entries for @file{binutils}.
3783 @c man end
3784 @end ignore
3785
3786 @node c++filt, addr2line, strip, Top
3787 @chapter c++filt
3788
3789 @kindex c++filt
3790 @cindex demangling C++ symbols
3791
3792 @c man title cxxfilt demangle C++ and Java symbols
3793
3794 @smallexample
3795 @c man begin SYNOPSIS cxxfilt
3796 c++filt [@option{-_}|@option{--strip-underscore}]
3797 [@option{-n}|@option{--no-strip-underscore}]
3798 [@option{-p}|@option{--no-params}]
3799 [@option{-t}|@option{--types}]
3800 [@option{-i}|@option{--no-verbose}]
3801 [@option{-r}|@option{--no-recurse-limit}]
3802 [@option{-R}|@option{--recurse-limit}]
3803 [@option{-s} @var{format}|@option{--format=}@var{format}]
3804 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3805 @c man end
3806 @end smallexample
3807
3808 @c man begin DESCRIPTION cxxfilt
3809
3810 @kindex cxxfilt
3811 The C++ and Java languages provide function overloading, which means
3812 that you can write many functions with the same name, providing that
3813 each function takes parameters of different types. In order to be
3814 able to distinguish these similarly named functions C++ and Java
3815 encode them into a low-level assembler name which uniquely identifies
3816 each different version. This process is known as @dfn{mangling}. The
3817 @command{c++filt}
3818 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3819 MS-DOS this program is named @command{CXXFILT}.}
3820 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3821 names into user-level names so that they can be read.
3822
3823 Every alphanumeric word (consisting of letters, digits, underscores,
3824 dollars, or periods) seen in the input is a potential mangled name.
3825 If the name decodes into a C++ name, the C++ name replaces the
3826 low-level name in the output, otherwise the original word is output.
3827 In this way you can pass an entire assembler source file, containing
3828 mangled names, through @command{c++filt} and see the same source file
3829 containing demangled names.
3830
3831 You can also use @command{c++filt} to decipher individual symbols by
3832 passing them on the command line:
3833
3834 @example
3835 c++filt @var{symbol}
3836 @end example
3837
3838 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3839 names from the standard input instead. All the results are printed on
3840 the standard output. The difference between reading names from the
3841 command line versus reading names from the standard input is that
3842 command-line arguments are expected to be just mangled names and no
3843 checking is performed to separate them from surrounding text. Thus
3844 for example:
3845
3846 @smallexample
3847 c++filt -n _Z1fv
3848 @end smallexample
3849
3850 will work and demangle the name to ``f()'' whereas:
3851
3852 @smallexample
3853 c++filt -n _Z1fv,
3854 @end smallexample
3855
3856 will not work. (Note the extra comma at the end of the mangled
3857 name which makes it invalid). This command however will work:
3858
3859 @smallexample
3860 echo _Z1fv, | c++filt -n
3861 @end smallexample
3862
3863 and will display ``f(),'', i.e., the demangled name followed by a
3864 trailing comma. This behaviour is because when the names are read
3865 from the standard input it is expected that they might be part of an
3866 assembler source file where there might be extra, extraneous
3867 characters trailing after a mangled name. For example:
3868
3869 @smallexample
3870 .type _Z1fv, @@function
3871 @end smallexample
3872
3873 @c man end
3874
3875 @c man begin OPTIONS cxxfilt
3876
3877 @table @env
3878 @item -_
3879 @itemx --strip-underscore
3880 On some systems, both the C and C++ compilers put an underscore in front
3881 of every name. For example, the C name @code{foo} gets the low-level
3882 name @code{_foo}. This option removes the initial underscore. Whether
3883 @command{c++filt} removes the underscore by default is target dependent.
3884
3885 @item -n
3886 @itemx --no-strip-underscore
3887 Do not remove the initial underscore.
3888
3889 @item -p
3890 @itemx --no-params
3891 When demangling the name of a function, do not display the types of
3892 the function's parameters.
3893
3894 @item -t
3895 @itemx --types
3896 Attempt to demangle types as well as function names. This is disabled
3897 by default since mangled types are normally only used internally in
3898 the compiler, and they can be confused with non-mangled names. For example,
3899 a function called ``a'' treated as a mangled type name would be
3900 demangled to ``signed char''.
3901
3902 @item -i
3903 @itemx --no-verbose
3904 Do not include implementation details (if any) in the demangled
3905 output.
3906
3907 @item -r
3908 @itemx -R
3909 @itemx --recurse-limit
3910 @itemx --no-recurse-limit
3911 @itemx --recursion-limit
3912 @itemx --no-recursion-limit
3913 Enables or disables a limit on the amount of recursion performed
3914 whilst demangling strings. Since the name mangling formats allow for
3915 an infinite level of recursion it is possible to create strings whose
3916 decoding will exhaust the amount of stack space available on the host
3917 machine, triggering a memory fault. The limit tries to prevent this
3918 from happening by restricting recursion to 2048 levels of nesting.
3919
3920 The default is for this limit to be enabled, but disabling it may be
3921 necessary in order to demangle truly complicated names. Note however
3922 that if the recursion limit is disabled then stack exhaustion is
3923 possible and any bug reports about such an event will be rejected.
3924
3925 The @option{-r} option is a synonym for the
3926 @option{--no-recurse-limit} option. The @option{-R} option is a
3927 synonym for the @option{--recurse-limit} option.
3928
3929 @item -s @var{format}
3930 @itemx --format=@var{format}
3931 @command{c++filt} can decode various methods of mangling, used by
3932 different compilers. The argument to this option selects which
3933 method it uses:
3934
3935 @table @code
3936 @item auto
3937 Automatic selection based on executable (the default method)
3938 @item gnu
3939 the one used by the @sc{gnu} C++ compiler (g++)
3940 @item lucid
3941 the one used by the Lucid compiler (lcc)
3942 @item arm
3943 the one specified by the C++ Annotated Reference Manual
3944 @item hp
3945 the one used by the HP compiler (aCC)
3946 @item edg
3947 the one used by the EDG compiler
3948 @item gnu-v3
3949 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3950 @item java
3951 the one used by the @sc{gnu} Java compiler (gcj)
3952 @item gnat
3953 the one used by the @sc{gnu} Ada compiler (GNAT).
3954 @end table
3955
3956 @item --help
3957 Print a summary of the options to @command{c++filt} and exit.
3958
3959 @item --version
3960 Print the version number of @command{c++filt} and exit.
3961 @end table
3962
3963 @c man end
3964
3965 @ignore
3966 @c man begin SEEALSO cxxfilt
3967 the Info entries for @file{binutils}.
3968 @c man end
3969 @end ignore
3970
3971 @quotation
3972 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3973 user interface are subject to change in future releases. In particular,
3974 a command-line option may be required in the future to decode a name
3975 passed as an argument on the command line; in other words,
3976
3977 @example
3978 c++filt @var{symbol}
3979 @end example
3980
3981 @noindent
3982 may in a future release become
3983
3984 @example
3985 c++filt @var{option} @var{symbol}
3986 @end example
3987 @end quotation
3988
3989 @node addr2line
3990 @chapter addr2line
3991
3992 @kindex addr2line
3993 @cindex address to file name and line number
3994
3995 @c man title addr2line convert addresses or symbol+offset into file names and line numbers
3996
3997 @smallexample
3998 @c man begin SYNOPSIS addr2line
3999 addr2line [@option{-a}|@option{--addresses}]
4000 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
4001 [@option{-C}|@option{--demangle}[=@var{style}]]
4002 [@option{-r}|@option{--no-recurse-limit}]
4003 [@option{-R}|@option{--recurse-limit}]
4004 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
4005 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
4006 [@option{-i}|@option{--inlines}]
4007 [@option{-p}|@option{--pretty-print}]
4008 [@option{-j}|@option{--section=}@var{name}]
4009 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
4010 [addr addr @dots{}]
4011 @c man end
4012 @end smallexample
4013
4014 @c man begin DESCRIPTION addr2line
4015
4016 @command{addr2line} translates addresses or symbol+offset into file names and line numbers.
4017 Given an address or symbol+offset in an executable or an offset in a section of a relocatable
4018 object, it uses the debugging information to figure out which file name and
4019 line number are associated with it.
4020
4021 The executable or relocatable object to use is specified with the @option{-e}
4022 option. The default is the file @file{a.out}. The section in the relocatable
4023 object to use is specified with the @option{-j} option.
4024
4025 @command{addr2line} has two modes of operation.
4026
4027 In the first, hexadecimal addresses or symbol+offset are specified on the command line,
4028 and @command{addr2line} displays the file name and line number for each
4029 address.
4030
4031 In the second, @command{addr2line} reads hexadecimal addresses or symbol+offset from
4032 standard input, and prints the file name and line number for each
4033 address on standard output. In this mode, @command{addr2line} may be used
4034 in a pipe to convert dynamically chosen addresses.
4035
4036 The format of the output is @samp{FILENAME:LINENO}. By default
4037 each input address generates one line of output.
4038
4039 Two options can generate additional lines before each
4040 @samp{FILENAME:LINENO} line (in that order).
4041
4042 If the @option{-a} option is used then a line with the input address
4043 is displayed.
4044
4045 If the @option{-f} option is used, then a line with the
4046 @samp{FUNCTIONNAME} is displayed. This is the name of the function
4047 containing the address.
4048
4049 One option can generate additional lines after the
4050 @samp{FILENAME:LINENO} line.
4051
4052 If the @option{-i} option is used and the code at the given address is
4053 present there because of inlining by the compiler then additional
4054 lines are displayed afterwards. One or two extra lines (if the
4055 @option{-f} option is used) are displayed for each inlined function.
4056
4057 Alternatively if the @option{-p} option is used then each input
4058 address generates a single, long, output line containing the address,
4059 the function name, the file name and the line number. If the
4060 @option{-i} option has also been used then any inlined functions will
4061 be displayed in the same manner, but on separate lines, and prefixed
4062 by the text @samp{(inlined by)}.
4063
4064 If the file name or function name can not be determined,
4065 @command{addr2line} will print two question marks in their place. If the
4066 line number can not be determined, @command{addr2line} will print 0.
4067
4068 When symbol+offset is used, +offset is optional, except when the symbol
4069 is ambigious with a hex number. The resolved symbols can be mangled
4070 or unmangled, except unmangled symbols with + are not allowed.
4071
4072 @c man end
4073
4074 @c man begin OPTIONS addr2line
4075
4076 The long and short forms of options, shown here as alternatives, are
4077 equivalent.
4078
4079 @table @env
4080 @item -a
4081 @itemx --addresses
4082 Display the address before the function name, file and line number
4083 information. The address is printed with a @samp{0x} prefix to easily
4084 identify it.
4085
4086 @item -b @var{bfdname}
4087 @itemx --target=@var{bfdname}
4088 @cindex object code format
4089 Specify that the object-code format for the object files is
4090 @var{bfdname}.
4091
4092 @item -C
4093 @itemx --demangle[=@var{style}]
4094 @cindex demangling in objdump
4095 Decode (@dfn{demangle}) low-level symbol names into user-level names.
4096 Besides removing any initial underscore prepended by the system, this
4097 makes C++ function names readable. Different compilers have different
4098 mangling styles. The optional demangling style argument can be used to
4099 choose an appropriate demangling style for your compiler. @xref{c++filt},
4100 for more information on demangling.
4101
4102 @item -e @var{filename}
4103 @itemx --exe=@var{filename}
4104 Specify the name of the executable for which addresses should be
4105 translated. The default file is @file{a.out}.
4106
4107 @item -f
4108 @itemx --functions
4109 Display function names as well as file and line number information.
4110
4111 @item -s
4112 @itemx --basenames
4113 Display only the base of each file name.
4114
4115 @item -i
4116 @itemx --inlines
4117 If the address belongs to a function that was inlined, the source
4118 information for all enclosing scopes back to the first non-inlined
4119 function will also be printed. For example, if @code{main} inlines
4120 @code{callee1} which inlines @code{callee2}, and address is from
4121 @code{callee2}, the source information for @code{callee1} and @code{main}
4122 will also be printed.
4123
4124 @item -j
4125 @itemx --section
4126 Read offsets relative to the specified section instead of absolute addresses.
4127
4128 @item -p
4129 @itemx --pretty-print
4130 Make the output more human friendly: each location are printed on one line.
4131 If option @option{-i} is specified, lines for all enclosing scopes are
4132 prefixed with @samp{(inlined by)}.
4133
4134 @item -r
4135 @itemx -R
4136 @itemx --recurse-limit
4137 @itemx --no-recurse-limit
4138 @itemx --recursion-limit
4139 @itemx --no-recursion-limit
4140 Enables or disables a limit on the amount of recursion performed
4141 whilst demangling strings. Since the name mangling formats allow for
4142 an infinite level of recursion it is possible to create strings whose
4143 decoding will exhaust the amount of stack space available on the host
4144 machine, triggering a memory fault. The limit tries to prevent this
4145 from happening by restricting recursion to 2048 levels of nesting.
4146
4147 The default is for this limit to be enabled, but disabling it may be
4148 necessary in order to demangle truly complicated names. Note however
4149 that if the recursion limit is disabled then stack exhaustion is
4150 possible and any bug reports about such an event will be rejected.
4151
4152 The @option{-r} option is a synonym for the
4153 @option{--no-recurse-limit} option. The @option{-R} option is a
4154 synonym for the @option{--recurse-limit} option.
4155
4156 Note this option is only effective if the @option{-C} or
4157 @option{--demangle} option has been enabled.
4158
4159 @end table
4160
4161 @c man end
4162
4163 @ignore
4164 @c man begin SEEALSO addr2line
4165 Info entries for @file{binutils}.
4166 @c man end
4167 @end ignore
4168
4169 @node windmc
4170 @chapter windmc
4171
4172 @command{windmc} may be used to generator Windows message resources.
4173
4174 @quotation
4175 @emph{Warning:} @command{windmc} is not always built as part of the binary
4176 utilities, since it is only useful for Windows targets.
4177 @end quotation
4178
4179 @c man title windmc generates Windows message resources
4180
4181 @smallexample
4182 @c man begin SYNOPSIS windmc
4183 windmc [options] input-file
4184 @c man end
4185 @end smallexample
4186
4187 @c man begin DESCRIPTION windmc
4188
4189 @command{windmc} reads message definitions from an input file (.mc) and
4190 translate them into a set of output files. The output files may be of
4191 four kinds:
4192
4193 @table @code
4194 @item h
4195 A C header file containing the message definitions.
4196
4197 @item rc
4198 A resource file compilable by the @command{windres} tool.
4199
4200 @item bin
4201 One or more binary files containing the resource data for a specific
4202 message language.
4203
4204 @item dbg
4205 A C include file that maps message id's to their symbolic name.
4206 @end table
4207
4208 The exact description of these different formats is available in
4209 documentation from Microsoft.
4210
4211 When @command{windmc} converts from the @code{mc} format to the @code{bin}
4212 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
4213 Windows Message Compiler.
4214
4215 @c man end
4216
4217 @c man begin OPTIONS windmc
4218
4219 @table @env
4220 @item -a
4221 @itemx --ascii_in
4222 Specifies that the input file specified is ASCII. This is the default
4223 behaviour.
4224
4225 @item -A
4226 @itemx --ascii_out
4227 Specifies that messages in the output @code{bin} files should be in ASCII
4228 format.
4229
4230 @item -b
4231 @itemx --binprefix
4232 Specifies that @code{bin} filenames should have to be prefixed by the
4233 basename of the source file.
4234
4235 @item -c
4236 @itemx --customflag
4237 Sets the customer bit in all message id's.
4238
4239 @item -C @var{codepage}
4240 @itemx --codepage_in @var{codepage}
4241 Sets the default codepage to be used to convert input file to UTF16. The
4242 default is ocdepage 1252.
4243
4244 @item -d
4245 @itemx --decimal_values
4246 Outputs the constants in the header file in decimal. Default is using
4247 hexadecimal output.
4248
4249 @item -e @var{ext}
4250 @itemx --extension @var{ext}
4251 The extension for the header file. The default is .h extension.
4252
4253 @item -F @var{target}
4254 @itemx --target @var{target}
4255 Specify the BFD format to use for a bin file as output. This
4256 is a BFD target name; you can use the @option{--help} option to see a list
4257 of supported targets. Normally @command{windmc} will use the default
4258 format, which is the first one listed by the @option{--help} option.
4259 @ifclear man
4260 @ref{Target Selection}.
4261 @end ifclear
4262
4263 @item -h @var{path}
4264 @itemx --headerdir @var{path}
4265 The target directory of the generated header file. The default is the
4266 current directory.
4267
4268 @item -H
4269 @itemx --help
4270 Displays a list of command-line options and then exits.
4271
4272 @item -m @var{characters}
4273 @itemx --maxlength @var{characters}
4274 Instructs @command{windmc} to generate a warning if the length
4275 of any message exceeds the number specified.
4276
4277 @item -n
4278 @itemx --nullterminate
4279 Terminate message text in @code{bin} files by zero. By default they are
4280 terminated by CR/LF.
4281
4282 @item -o
4283 @itemx --hresult_use
4284 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4285 file, using HRESULT definitions. Status codes are used if the flag is not
4286 specified.
4287
4288 @item -O @var{codepage}
4289 @itemx --codepage_out @var{codepage}
4290 Sets the default codepage to be used to output text files. The default
4291 is ocdepage 1252.
4292
4293 @item -r @var{path}
4294 @itemx --rcdir @var{path}
4295 The target directory for the generated @code{rc} script and the generated
4296 @code{bin} files that the resource compiler script includes. The default
4297 is the current directory.
4298
4299 @item -u
4300 @itemx --unicode_in
4301 Specifies that the input file is UTF16.
4302
4303 @item -U
4304 @itemx --unicode_out
4305 Specifies that messages in the output @code{bin} file should be in UTF16
4306 format. This is the default behaviour.
4307
4308 @item -v
4309 @item --verbose
4310 Enable verbose mode.
4311
4312 @item -V
4313 @item --version
4314 Prints the version number for @command{windmc}.
4315
4316 @item -x @var{path}
4317 @itemx --xdgb @var{path}
4318 The path of the @code{dbg} C include file that maps message id's to the
4319 symbolic name. No such file is generated without specifying the switch.
4320 @end table
4321
4322 @c man end
4323
4324 @ignore
4325 @c man begin SEEALSO windmc
4326 the Info entries for @file{binutils}.
4327 @c man end
4328 @end ignore
4329
4330 @node windres
4331 @chapter windres
4332
4333 @command{windres} may be used to manipulate Windows resources.
4334
4335 @quotation
4336 @emph{Warning:} @command{windres} is not always built as part of the binary
4337 utilities, since it is only useful for Windows targets.
4338 @end quotation
4339
4340 @c man title windres manipulate Windows resources
4341
4342 @smallexample
4343 @c man begin SYNOPSIS windres
4344 windres [options] [input-file] [output-file]
4345 @c man end
4346 @end smallexample
4347
4348 @c man begin DESCRIPTION windres
4349
4350 @command{windres} reads resources from an input file and copies them into
4351 an output file. Either file may be in one of three formats:
4352
4353 @table @code
4354 @item rc
4355 A text format read by the Resource Compiler.
4356
4357 @item res
4358 A binary format generated by the Resource Compiler.
4359
4360 @item coff
4361 A COFF object or executable.
4362 @end table
4363
4364 The exact description of these different formats is available in
4365 documentation from Microsoft.
4366
4367 When @command{windres} converts from the @code{rc} format to the @code{res}
4368 format, it is acting like the Windows Resource Compiler. When
4369 @command{windres} converts from the @code{res} format to the @code{coff}
4370 format, it is acting like the Windows @code{CVTRES} program.
4371
4372 When @command{windres} generates an @code{rc} file, the output is similar
4373 but not identical to the format expected for the input. When an input
4374 @code{rc} file refers to an external filename, an output @code{rc} file
4375 will instead include the file contents.
4376
4377 If the input or output format is not specified, @command{windres} will
4378 guess based on the file name, or, for the input file, the file contents.
4379 A file with an extension of @file{.rc} will be treated as an @code{rc}
4380 file, a file with an extension of @file{.res} will be treated as a
4381 @code{res} file, and a file with an extension of @file{.o} or
4382 @file{.exe} will be treated as a @code{coff} file.
4383
4384 If no output file is specified, @command{windres} will print the resources
4385 in @code{rc} format to standard output.
4386
4387 The normal use is for you to write an @code{rc} file, use @command{windres}
4388 to convert it to a COFF object file, and then link the COFF file into
4389 your application. This will make the resources described in the
4390 @code{rc} file available to Windows.
4391
4392 @c man end
4393
4394 @c man begin OPTIONS windres
4395
4396 @table @env
4397 @item -i @var{filename}
4398 @itemx --input @var{filename}
4399 The name of the input file. If this option is not used, then
4400 @command{windres} will use the first non-option argument as the input file
4401 name. If there are no non-option arguments, then @command{windres} will
4402 read from standard input. @command{windres} can not read a COFF file from
4403 standard input.
4404
4405 @item -o @var{filename}
4406 @itemx --output @var{filename}
4407 The name of the output file. If this option is not used, then
4408 @command{windres} will use the first non-option argument, after any used
4409 for the input file name, as the output file name. If there is no
4410 non-option argument, then @command{windres} will write to standard output.
4411 @command{windres} can not write a COFF file to standard output. Note,
4412 for compatibility with @command{rc} the option @option{-fo} is also
4413 accepted, but its use is not recommended.
4414
4415 @item -J @var{format}
4416 @itemx --input-format @var{format}
4417 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4418 @samp{coff}. If no input format is specified, @command{windres} will
4419 guess, as described above.
4420
4421 @item -O @var{format}
4422 @itemx --output-format @var{format}
4423 The output format to generate. @var{format} may be @samp{res},
4424 @samp{rc}, or @samp{coff}. If no output format is specified,
4425 @command{windres} will guess, as described above.
4426
4427 @item -F @var{target}
4428 @itemx --target @var{target}
4429 Specify the BFD format to use for a COFF file as input or output. This
4430 is a BFD target name; you can use the @option{--help} option to see a list
4431 of supported targets. Normally @command{windres} will use the default
4432 format, which is the first one listed by the @option{--help} option.
4433 @ifclear man
4434 @ref{Target Selection}.
4435 @end ifclear
4436
4437 @item --preprocessor @var{program}
4438 When @command{windres} reads an @code{rc} file, it runs it through the C
4439 preprocessor first. This option may be used to specify the preprocessor
4440 to use. The default preprocessor is @code{gcc}.
4441
4442 @item --preprocessor-arg @var{option}
4443 When @command{windres} reads an @code{rc} file, it runs it through
4444 the C preprocessor first. This option may be used to specify additional
4445 text to be passed to preprocessor on its command line.
4446 This option can be used multiple times to add multiple options to the
4447 preprocessor command line.
4448 If the @option{--preprocessor} option has not been specified then a
4449 default set of preprocessor arguments will be used, with any
4450 @option{--preprocessor-arg} options being placed after them on the
4451 command line. These default arguments are @code{-E},
4452 @code{-xc-header} and @code{-DRC_INVOKED}.
4453
4454 @item -I @var{directory}
4455 @itemx --include-dir @var{directory}
4456 Specify an include directory to use when reading an @code{rc} file.
4457 @command{windres} will pass this to the preprocessor as an @option{-I}
4458 option. @command{windres} will also search this directory when looking for
4459 files named in the @code{rc} file. If the argument passed to this command
4460 matches any of the supported @var{formats} (as described in the @option{-J}
4461 option), it will issue a deprecation warning, and behave just like the
4462 @option{-J} option. New programs should not use this behaviour. If a
4463 directory happens to match a @var{format}, simple prefix it with @samp{./}
4464 to disable the backward compatibility.
4465
4466 @item -D @var{target}
4467 @itemx --define @var{sym}[=@var{val}]
4468 Specify a @option{-D} option to pass to the preprocessor when reading an
4469 @code{rc} file.
4470
4471 @item -U @var{target}
4472 @itemx --undefine @var{sym}
4473 Specify a @option{-U} option to pass to the preprocessor when reading an
4474 @code{rc} file.
4475
4476 @item -r
4477 Ignored for compatibility with rc.
4478
4479 @item -v
4480 Enable verbose mode. This tells you what the preprocessor is if you
4481 didn't specify one.
4482
4483 @item -c @var{val}
4484 @item --codepage @var{val}
4485 Specify the default codepage to use when reading an @code{rc} file.
4486 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4487 codepage code. The valid range is from zero up to 0xffff, but the
4488 validity of the codepage is host and configuration dependent.
4489
4490 @item -l @var{val}
4491 @item --language @var{val}
4492 Specify the default language to use when reading an @code{rc} file.
4493 @var{val} should be a hexadecimal language code. The low eight bits are
4494 the language, and the high eight bits are the sublanguage.
4495
4496 @item --use-temp-file
4497 Use a temporary file to instead of using popen to read the output of
4498 the preprocessor. Use this option if the popen implementation is buggy
4499 on the host (eg., certain non-English language versions of Windows 95 and
4500 Windows 98 are known to have buggy popen where the output will instead
4501 go the console).
4502
4503 @item --no-use-temp-file
4504 Use popen, not a temporary file, to read the output of the preprocessor.
4505 This is the default behaviour.
4506
4507 @item -h
4508 @item --help
4509 Prints a usage summary.
4510
4511 @item -V
4512 @item --version
4513 Prints the version number for @command{windres}.
4514
4515 @item --yydebug
4516 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4517 this will turn on parser debugging.
4518 @end table
4519
4520 @c man end
4521
4522 @ignore
4523 @c man begin SEEALSO windres
4524 the Info entries for @file{binutils}.
4525 @c man end
4526 @end ignore
4527
4528 @node dlltool
4529 @chapter dlltool
4530 @cindex DLL
4531 @kindex dlltool
4532
4533 @command{dlltool} is used to create the files needed to create dynamic
4534 link libraries (DLLs) on systems which understand PE format image
4535 files such as Windows. A DLL contains an export table which contains
4536 information that the runtime loader needs to resolve references from a
4537 referencing program.
4538
4539 The export table is generated by this program by reading in a
4540 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4541 will be in the DLL. A @file{.o} file can contain information in
4542 special @samp{.drectve} sections with export information.
4543
4544 @quotation
4545 @emph{Note:} @command{dlltool} is not always built as part of the
4546 binary utilities, since it is only useful for those targets which
4547 support DLLs.
4548 @end quotation
4549
4550 @c man title dlltool create files needed to build and use DLLs
4551
4552 @smallexample
4553 @c man begin SYNOPSIS dlltool
4554 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4555 [@option{-b}|@option{--base-file} @var{base-file-name}]
4556 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4557 [@option{-z}|@option{--output-def} @var{def-file-name}]
4558 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4559 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4560 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4561 [@option{--exclude-symbols} @var{list}]
4562 [@option{--no-default-excludes}]
4563 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4564 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4565 [@option{-a}|@option{--add-indirect}]
4566 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4567 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4568 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4569 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4570 [@option{--use-nul-prefixed-import-tables}]
4571 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4572 [@option{-i}|@option{--interwork}]
4573 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4574 [@option{-v}|@option{--verbose}]
4575 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4576 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4577 [@option{--deterministic-libraries}] [@option{--non-deterministic-libraries}]
4578 [object-file @dots{}]
4579 @c man end
4580 @end smallexample
4581
4582 @c man begin DESCRIPTION dlltool
4583
4584 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4585 @option{-b} options as well as object files specified on the command
4586 line. It then processes these inputs and if the @option{-e} option has
4587 been specified it creates a exports file. If the @option{-l} option
4588 has been specified it creates a library file and if the @option{-z} option
4589 has been specified it creates a def file. Any or all of the @option{-e},
4590 @option{-l} and @option{-z} options can be present in one invocation of
4591 dlltool.
4592
4593 When creating a DLL, along with the source for the DLL, it is necessary
4594 to have three other files. @command{dlltool} can help with the creation of
4595 these files.
4596
4597 The first file is a @file{.def} file which specifies which functions are
4598 exported from the DLL, which functions the DLL imports, and so on. This
4599 is a text file and can be created by hand, or @command{dlltool} can be used
4600 to create it using the @option{-z} option. In this case @command{dlltool}
4601 will scan the object files specified on its command line looking for
4602 those functions which have been specially marked as being exported and
4603 put entries for them in the @file{.def} file it creates.
4604
4605 In order to mark a function as being exported from a DLL, it needs to
4606 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4607 section of the object file. This can be done in C by using the
4608 asm() operator:
4609
4610 @smallexample
4611 asm (".section .drectve");
4612 asm (".ascii \"-export:my_func\"");
4613
4614 int my_func (void) @{ @dots{} @}
4615 @end smallexample
4616
4617 The second file needed for DLL creation is an exports file. This file
4618 is linked with the object files that make up the body of the DLL and it
4619 handles the interface between the DLL and the outside world. This is a
4620 binary file and it can be created by giving the @option{-e} option to
4621 @command{dlltool} when it is creating or reading in a @file{.def} file.
4622
4623 The third file needed for DLL creation is the library file that programs
4624 will link with in order to access the functions in the DLL (an `import
4625 library'). This file can be created by giving the @option{-l} option to
4626 dlltool when it is creating or reading in a @file{.def} file.
4627
4628 If the @option{-y} option is specified, dlltool generates a delay-import
4629 library that can be used instead of the normal import library to allow
4630 a program to link to the dll only as soon as an imported function is
4631 called for the first time. The resulting executable will need to be
4632 linked to the static delayimp library containing __delayLoadHelper2(),
4633 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4634
4635 @command{dlltool} builds the library file by hand, but it builds the
4636 exports file by creating temporary files containing assembler statements
4637 and then assembling these. The @option{-S} command-line option can be
4638 used to specify the path to the assembler that dlltool will use,
4639 and the @option{-f} option can be used to pass specific flags to that
4640 assembler. The @option{-n} can be used to prevent dlltool from deleting
4641 these temporary assembler files when it is done, and if @option{-n} is
4642 specified twice then this will prevent dlltool from deleting the
4643 temporary object files it used to build the library.
4644
4645 Here is an example of creating a DLL from a source file @samp{dll.c} and
4646 also creating a program (from an object file called @samp{program.o})
4647 that uses that DLL:
4648
4649 @smallexample
4650 gcc -c dll.c
4651 dlltool -e exports.o -l dll.lib dll.o
4652 gcc dll.o exports.o -o dll.dll
4653 gcc program.o dll.lib -o program
4654 @end smallexample
4655
4656
4657 @command{dlltool} may also be used to query an existing import library
4658 to determine the name of the DLL to which it is associated. See the
4659 description of the @option{-I} or @option{--identify} option.
4660
4661 @c man end
4662
4663 @c man begin OPTIONS dlltool
4664
4665 The command-line options have the following meanings:
4666
4667 @table @env
4668
4669 @item -d @var{filename}
4670 @itemx --input-def @var{filename}
4671 @cindex input .def file
4672 Specifies the name of a @file{.def} file to be read in and processed.
4673
4674 @item -b @var{filename}
4675 @itemx --base-file @var{filename}
4676 @cindex base files
4677 Specifies the name of a base file to be read in and processed. The
4678 contents of this file will be added to the relocation section in the
4679 exports file generated by dlltool.
4680
4681 @item -e @var{filename}
4682 @itemx --output-exp @var{filename}
4683 Specifies the name of the export file to be created by dlltool.
4684
4685 @item -z @var{filename}
4686 @itemx --output-def @var{filename}
4687 Specifies the name of the @file{.def} file to be created by dlltool.
4688
4689 @item -l @var{filename}
4690 @itemx --output-lib @var{filename}
4691 Specifies the name of the library file to be created by dlltool.
4692
4693 @item -y @var{filename}
4694 @itemx --output-delaylib @var{filename}
4695 Specifies the name of the delay-import library file to be created by dlltool.
4696
4697 @item --deterministic-libraries
4698 @itemx --non-deterministic-libraries
4699 When creating output libraries in response to either the
4700 @option{--output-lib} or @option{--output-delaylib} options either use
4701 the value of zero for any timestamps, user ids and group ids created
4702 (@option{--deterministic-libraries}) or the actual timestamps, user
4703 ids and group ids (@option{--non-deterministic-libraries}).
4704
4705 @item --export-all-symbols
4706 Treat all global and weak defined symbols found in the input object
4707 files as symbols to be exported. There is a small list of symbols which
4708 are not exported by default; see the @option{--no-default-excludes}
4709 option. You may add to the list of symbols to not export by using the
4710 @option{--exclude-symbols} option.
4711
4712 @item --no-export-all-symbols
4713 Only export symbols explicitly listed in an input @file{.def} file or in
4714 @samp{.drectve} sections in the input object files. This is the default
4715 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4716 attributes in the source code.
4717
4718 @item --exclude-symbols @var{list}
4719 Do not export the symbols in @var{list}. This is a list of symbol names
4720 separated by comma or colon characters. The symbol names should not
4721 contain a leading underscore. This is only meaningful when
4722 @option{--export-all-symbols} is used.
4723
4724 @item --no-default-excludes
4725 When @option{--export-all-symbols} is used, it will by default avoid
4726 exporting certain special symbols. The current list of symbols to avoid
4727 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4728 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4729 to go ahead and export these special symbols. This is only meaningful
4730 when @option{--export-all-symbols} is used.
4731
4732 @item -S @var{path}
4733 @itemx --as @var{path}
4734 Specifies the path, including the filename, of the assembler to be used
4735 to create the exports file.
4736
4737 @item -f @var{options}
4738 @itemx --as-flags @var{options}
4739 Specifies any specific command-line options to be passed to the
4740 assembler when building the exports file. This option will work even if
4741 the @option{-S} option is not used. This option only takes one argument,
4742 and if it occurs more than once on the command line, then later
4743 occurrences will override earlier occurrences. So if it is necessary to
4744 pass multiple options to the assembler they should be enclosed in
4745 double quotes.
4746
4747 @item -D @var{name}
4748 @itemx --dll-name @var{name}
4749 Specifies the name to be stored in the @file{.def} file as the name of
4750 the DLL when the @option{-e} option is used. If this option is not
4751 present, then the filename given to the @option{-e} option will be
4752 used as the name of the DLL.
4753
4754 @item -m @var{machine}
4755 @itemx -machine @var{machine}
4756 Specifies the type of machine for which the library file should be
4757 built. @command{dlltool} has a built in default type, depending upon how
4758 it was created, but this option can be used to override that. This is
4759 normally only useful when creating DLLs for an ARM processor, when the
4760 contents of the DLL are actually encode using Thumb instructions.
4761
4762 @item -a
4763 @itemx --add-indirect
4764 Specifies that when @command{dlltool} is creating the exports file it
4765 should add a section which allows the exported functions to be
4766 referenced without using the import library. Whatever the hell that
4767 means!
4768
4769 @item -U
4770 @itemx --add-underscore
4771 Specifies that when @command{dlltool} is creating the exports file it
4772 should prepend an underscore to the names of @emph{all} exported symbols.
4773
4774 @item --no-leading-underscore
4775 @item --leading-underscore
4776 Specifies whether standard symbol should be forced to be prefixed, or
4777 not.
4778
4779 @item --add-stdcall-underscore
4780 Specifies that when @command{dlltool} is creating the exports file it
4781 should prepend an underscore to the names of exported @emph{stdcall}
4782 functions. Variable names and non-stdcall function names are not modified.
4783 This option is useful when creating GNU-compatible import libs for third
4784 party DLLs that were built with MS-Windows tools.
4785
4786 @item -k
4787 @itemx --kill-at
4788 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4789 of stdcall functions that will be imported from the DLL. This is
4790 useful when creating an import library for a DLL which exports stdcall
4791 functions but without the usual @samp{@@<number>} symbol name suffix.
4792
4793 This does not change the naming of symbols provided by the import library
4794 to programs linked against it, but only the entries in the import table
4795 (ie the .idata section).
4796
4797 @item -A
4798 @itemx --add-stdcall-alias
4799 Specifies that when @command{dlltool} is creating the exports file it
4800 should add aliases for stdcall symbols without @samp{@@ <number>}
4801 in addition to the symbols with @samp{@@ <number>}.
4802
4803 @item -p
4804 @itemx --ext-prefix-alias @var{prefix}
4805 Causes @command{dlltool} to create external aliases for all DLL
4806 imports with the specified prefix. The aliases are created for both
4807 external and import symbols with no leading underscore.
4808
4809 @item -x
4810 @itemx --no-idata4
4811 Specifies that when @command{dlltool} is creating the exports and library
4812 files it should omit the @code{.idata4} section. This is for compatibility
4813 with certain operating systems.
4814
4815 @item --use-nul-prefixed-import-tables
4816 Specifies that when @command{dlltool} is creating the exports and library
4817 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4818 element. This emulates old gnu import library generation of
4819 @code{dlltool}. By default this option is turned off.
4820
4821 @item -c
4822 @itemx --no-idata5
4823 Specifies that when @command{dlltool} is creating the exports and library
4824 files it should omit the @code{.idata5} section. This is for compatibility
4825 with certain operating systems.
4826
4827 @item -I @var{filename}
4828 @itemx --identify @var{filename}
4829 Specifies that @command{dlltool} should inspect the import library
4830 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4831 of the associated DLL(s). This can be performed in addition to any
4832 other operations indicated by the other options and arguments.
4833 @command{dlltool} fails if the import library does not exist or is not
4834 actually an import library. See also @option{--identify-strict}.
4835
4836 @item --identify-strict
4837 Modifies the behavior of the @option{--identify} option, such
4838 that an error is reported if @var{filename} is associated with
4839 more than one DLL.
4840
4841 @item -i
4842 @itemx --interwork
4843 Specifies that @command{dlltool} should mark the objects in the library
4844 file and exports file that it produces as supporting interworking
4845 between ARM and Thumb code.
4846
4847 @item -n
4848 @itemx --nodelete
4849 Makes @command{dlltool} preserve the temporary assembler files it used to
4850 create the exports file. If this option is repeated then dlltool will
4851 also preserve the temporary object files it uses to create the library
4852 file.
4853
4854 @item -t @var{prefix}
4855 @itemx --temp-prefix @var{prefix}
4856 Makes @command{dlltool} use @var{prefix} when constructing the names of
4857 temporary assembler and object files. By default, the temp file prefix
4858 is generated from the pid.
4859
4860 @item -v
4861 @itemx --verbose
4862 Make dlltool describe what it is doing.
4863
4864 @item -h
4865 @itemx --help
4866 Displays a list of command-line options and then exits.
4867
4868 @item -V
4869 @itemx --version
4870 Displays dlltool's version number and then exits.
4871
4872 @end table
4873
4874 @c man end
4875
4876 @menu
4877 * def file format:: The format of the dlltool @file{.def} file
4878 @end menu
4879
4880 @node def file format
4881 @section The format of the @command{dlltool} @file{.def} file
4882
4883 A @file{.def} file contains any number of the following commands:
4884
4885 @table @asis
4886
4887 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4888 The result is going to be named @var{name}@code{.exe}.
4889
4890 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4891 The result is going to be named @var{name}@code{.dll}.
4892 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4893 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4894 details).
4895
4896 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4897 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4898 Declares @var{name1} as an exported symbol from the DLL, with optional
4899 ordinal number @var{integer}, or declares @var{name1} as an alias
4900 (forward) of the function @var{external-name} in the DLL.
4901 If @var{its_name} is specified, this name is used as string in export table.
4902 @var{module-name}.
4903 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4904 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4905 If you want to use LIBRARY as name then you need to quote it.
4906
4907 @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{]} *}
4908 Declares that @var{external-name} or the exported function whose
4909 ordinal number is @var{integer} is to be imported from the file
4910 @var{module-name}. If @var{internal-name} is specified then this is
4911 the name that the imported function will be referred to in the body of
4912 the DLL.
4913 If @var{its_name} is specified, this name is used as string in import table.
4914 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4915 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4916 If you want to use LIBRARY as name then you need to quote it.
4917
4918 @item @code{DESCRIPTION} @var{string}
4919 Puts @var{string} into the output @file{.exp} file in the
4920 @code{.rdata} section.
4921
4922 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4923 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4924 Generates @code{--stack} or @code{--heap}
4925 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4926 section. The linker will see this and act upon it.
4927
4928 @item @code{CODE} @var{attr} @code{+}
4929 @item @code{DATA} @var{attr} @code{+}
4930 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4931 Generates @code{--attr} @var{section-name} @var{attr} in the output
4932 @code{.drectve} section, where @var{attr} is one of @code{READ},
4933 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4934 this and act upon it.
4935
4936 @end table
4937
4938 @ignore
4939 @c man begin SEEALSO dlltool
4940 The Info pages for @file{binutils}.
4941 @c man end
4942 @end ignore
4943
4944 @node readelf
4945 @chapter readelf
4946
4947 @cindex ELF file information
4948 @kindex readelf
4949
4950 @c man title readelf display information about ELF files
4951
4952 @smallexample
4953 @c man begin SYNOPSIS readelf
4954 readelf [@option{-a}|@option{--all}]
4955 [@option{-h}|@option{--file-header}]
4956 [@option{-l}|@option{--program-headers}|@option{--segments}]
4957 [@option{-S}|@option{--section-headers}|@option{--sections}]
4958 [@option{-g}|@option{--section-groups}]
4959 [@option{-t}|@option{--section-details}]
4960 [@option{-e}|@option{--headers}]
4961 [@option{-s}|@option{--syms}|@option{--symbols}]
4962 [@option{--dyn-syms}|@option{--lto-syms}]
4963 [@option{--sym-base=[0|8|10|16]}]
4964 [@option{--demangle@var{=style}}|@option{--no-demangle}]
4965 [@option{--quiet}]
4966 [@option{--recurse-limit}|@option{--no-recurse-limit}]
4967 [@option{-U} @var{method}|@option{--unicode=}@var{method}]
4968 [@option{-X}|@option{--extra-sym-info}|@option{--no-extra-sym-info}]
4969 [@option{-n}|@option{--notes}]
4970 [@option{-r}|@option{--relocs}]
4971 [@option{-u}|@option{--unwind}]
4972 [@option{-d}|@option{--dynamic}]
4973 [@option{-V}|@option{--version-info}]
4974 [@option{-A}|@option{--arch-specific}]
4975 [@option{-D}|@option{--use-dynamic}]
4976 [@option{-L}|@option{--lint}|@option{--enable-checks}]
4977 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4978 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4979 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4980 [@option{-z}|@option{--decompress}]
4981 [@option{-c}|@option{--archive-index}]
4982 [@option{-w[lLiaprmfFsoORtUuTgAck]}|
4983 @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]]
4984 [@option{-wK}|@option{--debug-dump=follow-links}]
4985 [@option{-wN}|@option{--debug-dump=no-follow-links}]
4986 [@option{-wD}|@option{--debug-dump=use-debuginfod}]
4987 [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
4988 [@option{-P}|@option{--process-links}]
4989 [@option{--dwarf-depth=@var{n}}]
4990 [@option{--dwarf-start=@var{n}}]
4991 [@option{--ctf=}@var{section}]
4992 [@option{--ctf-parent=}@var{section}]
4993 [@option{--ctf-symbols=}@var{section}]
4994 [@option{--ctf-strings=}@var{section}]
4995 [@option{--sframe=}@var{section}]
4996 [@option{-I}|@option{--histogram}]
4997 [@option{-v}|@option{--version}]
4998 [@option{-W}|@option{--wide}]
4999 [@option{-T}|@option{--silent-truncation}]
5000 [@option{-H}|@option{--help}]
5001 @var{elffile}@dots{}
5002 @c man end
5003 @end smallexample
5004
5005 @c man begin DESCRIPTION readelf
5006
5007 @command{readelf} displays information about one or more ELF format object
5008 files. The options control what particular information to display.
5009
5010 @var{elffile}@dots{} are the object files to be examined. 32-bit and
5011 64-bit ELF files are supported, as are archives containing ELF files.
5012
5013 This program performs a similar function to @command{objdump} but it
5014 goes into more detail and it exists independently of the @sc{bfd}
5015 library, so if there is a bug in @sc{bfd} then readelf will not be
5016 affected.
5017
5018 @c man end
5019
5020 @c man begin OPTIONS readelf
5021
5022 The long and short forms of options, shown here as alternatives, are
5023 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
5024 given.
5025
5026 @table @env
5027 @item -a
5028 @itemx --all
5029 Equivalent to specifying @option{--file-header},
5030 @option{--program-headers}, @option{--sections}, @option{--symbols},
5031 @option{--relocs}, @option{--dynamic}, @option{--notes},
5032 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
5033 @option{--section-groups} and @option{--histogram}.
5034
5035 Note - this option does not enable @option{--use-dynamic} itself, so
5036 if that option is not present on the command line then dynamic symbols
5037 and dynamic relocs will not be displayed.
5038
5039 @item -h
5040 @itemx --file-header
5041 @cindex ELF file header information
5042 Displays the information contained in the ELF header at the start of the
5043 file.
5044
5045 @item -l
5046 @itemx --program-headers
5047 @itemx --segments
5048 @cindex ELF program header information
5049 @cindex ELF segment information
5050 Displays the information contained in the file's segment headers, if it
5051 has any.
5052
5053 @item --quiet
5054 @cindex quiet
5055 Suppress "no symbols" diagnostic.
5056
5057 @item -S
5058 @itemx --sections
5059 @itemx --section-headers
5060 @cindex ELF section information
5061 Displays the information contained in the file's section headers, if it
5062 has any.
5063
5064 @item -g
5065 @itemx --section-groups
5066 @cindex ELF section group information
5067 Displays the information contained in the file's section groups, if it
5068 has any.
5069
5070 @item -t
5071 @itemx --section-details
5072 @cindex ELF section information
5073 Displays the detailed section information. Implies @option{-S}.
5074
5075 @item -s
5076 @itemx --symbols
5077 @itemx --syms
5078 @cindex ELF symbol table information
5079 Displays the entries in symbol table section of the file, if it has one.
5080 If a symbol has version information associated with it then this is
5081 displayed as well. The version string is displayed as a suffix to the
5082 symbol name, preceded by an @@ character. For example
5083 @samp{foo@@VER_1}. If the version is the default version to be used
5084 when resolving unversioned references to the symbol then it is
5085 displayed as a suffix preceded by two @@ characters. For example
5086 @samp{foo@@@@VER_2}.
5087
5088 @item --dyn-syms
5089 @cindex ELF dynamic symbol table information
5090 Displays the entries in dynamic symbol table section of the file, if it
5091 has one. The output format is the same as the format used by the
5092 @option{--syms} option.
5093
5094 @item --lto-syms
5095 @cindex LTO symbol table
5096 Displays the contents of any LTO symbol tables in the file.
5097
5098 @item --sym-base=[0|8|10|16]
5099 @cindex symbol table size base
5100 Forces the size field of the symbol table to use the given base. Any
5101 unrecognized options will be treated as @samp{0}. @option{--sym-base=0}
5102 represents the default and legacy behaviour. This will output sizes as decimal
5103 for numbers less than 100000. For sizes 100000 and greater hexadecimal notation
5104 will be used with a 0x prefix.
5105 @option{--sym-base=8} will give the symbol sizes in octal.
5106 @option{--sym-base=10} will always give the symbol sizes in decimal.
5107 @option{--sym-base=16} will always give the symbol sizes in hexadecimal with a
5108 0x prefix.
5109
5110 @item -C
5111 @itemx --demangle[=@var{style}]
5112 @cindex demangling in nm
5113 Decode (@dfn{demangle}) low-level symbol names into user-level names.
5114 This makes C++ function names readable. Different compilers have
5115 different mangling styles. The optional demangling style argument can
5116 be used to choose an appropriate demangling style for your
5117 compiler. @xref{c++filt}, for more information on demangling.
5118
5119 @item --no-demangle
5120 Do not demangle low-level symbol names. This is the default.
5121
5122 @item --recurse-limit
5123 @itemx --no-recurse-limit
5124 @itemx --recursion-limit
5125 @itemx --no-recursion-limit
5126 Enables or disables a limit on the amount of recursion performed
5127 whilst demangling strings. Since the name mangling formats allow for
5128 an infinite level of recursion it is possible to create strings whose
5129 decoding will exhaust the amount of stack space available on the host
5130 machine, triggering a memory fault. The limit tries to prevent this
5131 from happening by restricting recursion to 2048 levels of nesting.
5132
5133 The default is for this limit to be enabled, but disabling it may be
5134 necessary in order to demangle truly complicated names. Note however
5135 that if the recursion limit is disabled then stack exhaustion is
5136 possible and any bug reports about such an event will be rejected.
5137
5138 @item -U @var{[d|i|l|e|x|h]}
5139 @itemx --unicode=[default|invalid|locale|escape|hex|highlight]
5140 Controls the display of non-ASCII characters in identifier names.
5141 The default (@option{--unicode=locale} or @option{--unicode=default}) is
5142 to treat them as multibyte characters and display them in the current
5143 locale. All other versions of this option treat the bytes as UTF-8
5144 encoded values and attempt to interpret them. If they cannot be
5145 interpreted or if the @option{--unicode=invalid} option is used then
5146 they are displayed as a sequence of hex bytes, encloses in curly
5147 parethesis characters.
5148
5149 Using the @option{--unicode=escape} option will display the characters
5150 as as unicode escape sequences (@var{\uxxxx}). Using the
5151 @option{--unicode=hex} will display the characters as hex byte
5152 sequences enclosed between angle brackets.
5153
5154 Using the @option{--unicode=highlight} will display the characters as
5155 unicode escape sequences but it will also highlighted them in red,
5156 assuming that colouring is supported by the output device. The
5157 colouring is intended to draw attention to the presence of unicode
5158 sequences when they might not be expected.
5159
5160 @item -X
5161 @itemx --extra-sym-info
5162 When displaying details of symbols, include extra information not
5163 normally presented. Currently this just adds the name of the section
5164 referenced by the symbol's index field, if there is one. In the
5165 future more information may be displayed when this option is enabled.
5166
5167 Enabling this option effectively enables the @option{--wide} option as
5168 well, at least when displaying symbol information.
5169
5170 @item --no-extra-sym-info
5171 Disables the effect of the @option{--extra-sym-info} option. This
5172 is the default.
5173
5174 @item -e
5175 @itemx --headers
5176 Display all the headers in the file. Equivalent to @option{-h -l -S}.
5177
5178 @item -n
5179 @itemx --notes
5180 @cindex ELF notes
5181 Displays the contents of the NOTE segments and/or sections, if any.
5182
5183 @item -r
5184 @itemx --relocs
5185 @cindex ELF reloc information
5186 Displays the contents of the file's relocation section, if it has one.
5187
5188 @item -u
5189 @itemx --unwind
5190 @cindex unwind information
5191 Displays the contents of the file's unwind section, if it has one. Only
5192 the unwind sections for IA64 ELF files, as well as ARM unwind tables
5193 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
5194 support is not yet implemented for your architecture you could try
5195 dumping the contents of the @var{.eh_frames} section using the
5196 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
5197 options.
5198
5199 @item -d
5200 @itemx --dynamic
5201 @cindex ELF dynamic section information
5202 Displays the contents of the file's dynamic section, if it has one.
5203
5204 @item -V
5205 @itemx --version-info
5206 @cindex ELF version sections information
5207 Displays the contents of the version sections in the file, it they
5208 exist.
5209
5210 @item -A
5211 @itemx --arch-specific
5212 Displays architecture-specific information in the file, if there
5213 is any.
5214
5215 @item -D
5216 @itemx --use-dynamic
5217 When displaying symbols, this option makes @command{readelf} use the
5218 symbol hash tables in the file's dynamic section, rather than the
5219 symbol table sections.
5220
5221 When displaying relocations, this option makes @command{readelf}
5222 display the dynamic relocations rather than the static relocations.
5223
5224 @item -L
5225 @itemx --lint
5226 @itemx --enable-checks
5227 Displays warning messages about possible problems with the file(s)
5228 being examined. If used on its own then all of the contents of the
5229 file(s) will be examined. If used with one of the dumping options
5230 then the warning messages will only be produced for the things being
5231 displayed.
5232
5233 @item -x <number or name>
5234 @itemx --hex-dump=<number or name>
5235 Displays the contents of the indicated section as a hexadecimal bytes.
5236 A number identifies a particular section by index in the section table;
5237 any other string identifies all sections with that name in the object file.
5238
5239 @item -R <number or name>
5240 @itemx --relocated-dump=<number or name>
5241 Displays the contents of the indicated section as a hexadecimal
5242 bytes. A number identifies a particular section by index in the
5243 section table; any other string identifies all sections with that name
5244 in the object file. The contents of the section will be relocated
5245 before they are displayed.
5246
5247 @item -p <number or name>
5248 @itemx --string-dump=<number or name>
5249 Displays the contents of the indicated section as printable strings.
5250 A number identifies a particular section by index in the section table;
5251 any other string identifies all sections with that name in the object file.
5252
5253 @item -z
5254 @itemx --decompress
5255 Requests that the section(s) being dumped by @option{x}, @option{R} or
5256 @option{p} options are decompressed before being displayed. If the
5257 section(s) are not compressed then they are displayed as is.
5258
5259 @item -c
5260 @itemx --archive-index
5261 @cindex Archive file symbol index information
5262 Displays the file symbol index information contained in the header part
5263 of binary archives. Performs the same function as the @option{t}
5264 command to @command{ar}, but without using the BFD library. @xref{ar}.
5265
5266 @item -w[lLiaprmfFsOoRtUuTgAckK]
5267 @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]
5268 @include debug.options.texi
5269
5270 @item -P
5271 @itemx --process-links
5272 Display the contents of non-debug sections found in separate debuginfo
5273 files that are linked to the main file. This option automatically
5274 implies the @option{-wK} option, and only sections requested by other
5275 command line options will be displayed.
5276
5277 @include ctf.options.texi
5278 @item --ctf-symbols=@var{section}
5279 @item --ctf-strings=@var{section}
5280 Specify the name of another section from which the CTF file can inherit
5281 strings and symbols. By default, the @code{.symtab} and its linked
5282 string table are used.
5283
5284 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
5285 other must be specified as well.
5286
5287 @item -I
5288 @itemx --histogram
5289 Display a histogram of bucket list lengths when displaying the contents
5290 of the symbol tables.
5291
5292 @item -v
5293 @itemx --version
5294 Display the version number of readelf.
5295
5296 @item -W
5297 @itemx --wide
5298 Don't break output lines to fit into 80 columns. By default
5299 @command{readelf} breaks section header and segment listing lines for
5300 64-bit ELF files, so that they fit into 80 columns. This option causes
5301 @command{readelf} to print each section header resp. each segment one a
5302 single line, which is far more readable on terminals wider than 80 columns.
5303
5304 @item -T
5305 @itemx --silent-truncation
5306 Normally when readelf is displaying a symbol name, and it has to
5307 truncate the name to fit into an 80 column display, it will add a
5308 suffix of @code{[...]} to the name. This command line option
5309 disables this behaviour, allowing 5 more characters of the name to be
5310 displayed and restoring the old behaviour of readelf (prior to release
5311 2.35).
5312
5313 @item -H
5314 @itemx --help
5315 Display the command-line options understood by @command{readelf}.
5316
5317 @end table
5318
5319 @c man end
5320
5321 @ignore
5322 @c man begin SEEALSO readelf
5323 objdump(1), and the Info entries for @file{binutils}.
5324 @c man end
5325 @end ignore
5326
5327 @node elfedit
5328 @chapter elfedit
5329
5330 @cindex Update ELF header
5331 @kindex elfedit
5332
5333 @c man title elfedit update ELF header and program property of ELF files
5334
5335 @smallexample
5336 @c man begin SYNOPSIS elfedit
5337 elfedit [@option{--input-mach=}@var{machine}]
5338 [@option{--input-type=}@var{type}]
5339 [@option{--input-osabi=}@var{osabi}]
5340 [@option{--input-abiversion=}@var{version}]
5341 @option{--output-mach=}@var{machine}
5342 @option{--output-type=}@var{type}
5343 @option{--output-osabi=}@var{osabi}
5344 @option{--output-abiversion=}@var{version}
5345 @option{--enable-x86-feature=}@var{feature}
5346 @option{--disable-x86-feature=}@var{feature}
5347 [@option{-v}|@option{--version}]
5348 [@option{-h}|@option{--help}]
5349 @var{elffile}@dots{}
5350 @c man end
5351 @end smallexample
5352
5353 @c man begin DESCRIPTION elfedit
5354
5355 @command{elfedit} updates the ELF header and program property of ELF
5356 files which have the matching ELF machine and file types. The options
5357 control how and which fields in the ELF header and program property
5358 should be updated.
5359
5360 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
5361 64-bit ELF files are supported, as are archives containing ELF files.
5362 @c man end
5363
5364 @c man begin OPTIONS elfedit
5365
5366 The long and short forms of options, shown here as alternatives, are
5367 equivalent. At least one of the @option{--output-mach},
5368 @option{--output-type}, @option{--output-osabi},
5369 @option{--output-abiversion},
5370 @option{--enable-x86-feature} and @option{--disable-x86-feature}
5371 options must be given.
5372
5373 @table @env
5374
5375 @item --input-mach=@var{machine}
5376 Set the matching input ELF machine type to @var{machine}. If
5377 @option{--input-mach} isn't specified, it will match any ELF
5378 machine types.
5379
5380 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5381 @var{K1OM} and @var{x86-64}.
5382
5383 @item --output-mach=@var{machine}
5384 Change the ELF machine type in the ELF header to @var{machine}. The
5385 supported ELF machine types are the same as @option{--input-mach}.
5386
5387 @item --input-type=@var{type}
5388 Set the matching input ELF file type to @var{type}. If
5389 @option{--input-type} isn't specified, it will match any ELF file types.
5390
5391 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5392
5393 @item --output-type=@var{type}
5394 Change the ELF file type in the ELF header to @var{type}. The
5395 supported ELF types are the same as @option{--input-type}.
5396
5397 @item --input-osabi=@var{osabi}
5398 Set the matching input ELF file OSABI to @var{osabi}. If
5399 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5400
5401 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5402 @var{GNU}, @var{Linux} (alias for @var{GNU}),
5403 @var{Solaris}, @var{AIX}, @var{Irix},
5404 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5405 @var{NSK}, @var{AROS} and @var{FenixOS}.
5406
5407 @item --output-osabi=@var{osabi}
5408 Change the ELF OSABI in the ELF header to @var{osabi}. The
5409 supported ELF OSABI are the same as @option{--input-osabi}.
5410
5411 @item --input-abiversion=@var{version}
5412 Set the matching input ELF file ABIVERSION to @var{version}.
5413 @var{version} must be between 0 and 255. If @option{--input-abiversion}
5414 isn't specified, it will match any ELF ABIVERSIONs.
5415
5416 @item --output-abiversion=@var{version}
5417 Change the ELF ABIVERSION in the ELF header to @var{version}.
5418 @var{version} must be between 0 and 255.
5419
5420 @item --enable-x86-feature=@var{feature}
5421 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5422 ELF files with machine types of @var{i386} or @var{x86-64}. The
5423 supported features are, @var{ibt}, @var{shstk}, @var{lam_u48} and
5424 @var{lam_u57}.
5425
5426 @item --disable-x86-feature=@var{feature}
5427 Clear the @var{feature} bit in program property in @var{exec} or
5428 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5429 The supported features are the same as @option{--enable-x86-feature}.
5430
5431 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5432 are available only on hosts with @samp{mmap} support.
5433
5434 @item -v
5435 @itemx --version
5436 Display the version number of @command{elfedit}.
5437
5438 @item -h
5439 @itemx --help
5440 Display the command-line options understood by @command{elfedit}.
5441
5442 @end table
5443
5444 @c man end
5445
5446 @ignore
5447 @c man begin SEEALSO elfedit
5448 readelf(1), and the Info entries for @file{binutils}.
5449 @c man end
5450 @end ignore
5451
5452 @node Common Options
5453 @chapter Common Options
5454
5455 The following command-line options are supported by all of the
5456 programs described in this manual.
5457
5458 @c man begin OPTIONS
5459 @table @env
5460 @include at-file.texi
5461 @c man end
5462
5463 @item --help
5464 Display the command-line options supported by the program.
5465
5466 @item --version
5467 Display the version number of the program.
5468
5469 @c man begin OPTIONS
5470 @end table
5471 @c man end
5472
5473 @node Selecting the Target System
5474 @chapter Selecting the Target System
5475
5476 You can specify two aspects of the target system to the @sc{gnu}
5477 binary file utilities, each in several ways:
5478
5479 @itemize @bullet
5480 @item
5481 the target
5482
5483 @item
5484 the architecture
5485 @end itemize
5486
5487 In the following summaries, the lists of ways to specify values are in
5488 order of decreasing precedence. The ways listed first override those
5489 listed later.
5490
5491 The commands to list valid values only list the values for which the
5492 programs you are running were configured. If they were configured with
5493 @option{--enable-targets=all}, the commands list most of the available
5494 values, but a few are left out; not all targets can be configured in at
5495 once because some of them can only be configured @dfn{native} (on hosts
5496 with the same type as the target system).
5497
5498 @menu
5499 * Target Selection::
5500 * Architecture Selection::
5501 @end menu
5502
5503 @node Target Selection
5504 @section Target Selection
5505
5506 A @dfn{target} is an object file format. A given target may be
5507 supported for multiple architectures (@pxref{Architecture Selection}).
5508 A target selection may also have variations for different operating
5509 systems or architectures.
5510
5511 The command to list valid target values is @samp{objdump -i}
5512 (the first column of output contains the relevant information).
5513
5514 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5515 @samp{a.out-sunos-big}.
5516
5517 You can also specify a target using a configuration triplet. This is
5518 the same sort of name that is passed to @file{configure} to specify a
5519 target. When you use a configuration triplet as an argument, it must be
5520 fully canonicalized. You can see the canonical version of a triplet by
5521 running the shell script @file{config.sub} which is included with the
5522 sources.
5523
5524 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5525 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5526
5527 @subheading @command{objdump} Target
5528
5529 Ways to specify:
5530
5531 @enumerate
5532 @item
5533 command-line option: @option{-b} or @option{--target}
5534
5535 @item
5536 environment variable @code{GNUTARGET}
5537
5538 @item
5539 deduced from the input file
5540 @end enumerate
5541
5542 @subheading @command{objcopy} and @command{strip} Input Target
5543
5544 Ways to specify:
5545
5546 @enumerate
5547 @item
5548 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5549
5550 @item
5551 environment variable @code{GNUTARGET}
5552
5553 @item
5554 deduced from the input file
5555 @end enumerate
5556
5557 @subheading @command{objcopy} and @command{strip} Output Target
5558
5559 Ways to specify:
5560
5561 @enumerate
5562 @item
5563 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5564
5565 @item
5566 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5567
5568 @item
5569 environment variable @code{GNUTARGET}
5570
5571 @item
5572 deduced from the input file
5573 @end enumerate
5574
5575 @subheading @command{nm}, @command{size}, and @command{strings} Target
5576
5577 Ways to specify:
5578
5579 @enumerate
5580 @item
5581 command-line option: @option{--target}
5582
5583 @item
5584 environment variable @code{GNUTARGET}
5585
5586 @item
5587 deduced from the input file
5588 @end enumerate
5589
5590 @node Architecture Selection
5591 @section Architecture Selection
5592
5593 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5594 to run. Its name may contain a colon, separating the name of the
5595 processor family from the name of the particular @sc{cpu}.
5596
5597 The command to list valid architecture values is @samp{objdump -i} (the
5598 second column contains the relevant information).
5599
5600 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5601
5602 @subheading @command{objdump} Architecture
5603
5604 Ways to specify:
5605
5606 @enumerate
5607 @item
5608 command-line option: @option{-m} or @option{--architecture}
5609
5610 @item
5611 deduced from the input file
5612 @end enumerate
5613
5614 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5615
5616 Ways to specify:
5617
5618 @enumerate
5619 @item
5620 deduced from the input file
5621 @end enumerate
5622
5623 @node debuginfod
5624 @chapter debuginfod
5625 @cindex separate debug files
5626
5627 debuginfod is a web service that indexes ELF/DWARF debugging resources
5628 by build-id and serves them over HTTP. For more information see:
5629 @emph{https://sourceware.org/elfutils/Debuginfod.html}
5630
5631 Binutils can be built with the debuginfod client library
5632 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5633 This option is enabled by default if @code{libdebuginfod} is installed
5634 and found at configure time. This allows @command{objdump} and
5635 @command{readelf} to automatically query debuginfod servers for
5636 separate debug files when the files are otherwise not found.
5637
5638 debuginfod is packaged with elfutils, starting with version 0.178.
5639 You can get the latest version from `https://sourceware.org/elfutils/'.
5640
5641 The DWARF info dumping tools (@command{readelf} and @command{objdump})
5642 have options to control when they should access the debuginfod
5643 servers. By default this access is enabled.
5644
5645 @node Reporting Bugs
5646 @chapter Reporting Bugs
5647 @cindex bugs
5648 @cindex reporting bugs
5649
5650 Your bug reports play an essential role in making the binary utilities
5651 reliable.
5652
5653 Reporting a bug may help you by bringing a solution to your problem, or
5654 it may not. But in any case the principal function of a bug report is
5655 to help the entire community by making the next version of the binary
5656 utilities work better. Bug reports are your contribution to their
5657 maintenance.
5658
5659 In order for a bug report to serve its purpose, you must include the
5660 information that enables us to fix the bug.
5661
5662 @menu
5663 * Bug Criteria:: Have you found a bug?
5664 * Bug Reporting:: How to report bugs
5665 @end menu
5666
5667 @node Bug Criteria
5668 @section Have You Found a Bug?
5669 @cindex bug criteria
5670
5671 If you are not sure whether you have found a bug, here are some guidelines:
5672
5673 @itemize @bullet
5674 @cindex fatal signal
5675 @cindex crash
5676 @item
5677 If a binary utility gets a fatal signal, for any input whatever, that is
5678 a bug. Reliable utilities never crash.
5679
5680 @cindex error on valid input
5681 @item
5682 If a binary utility produces an error message for valid input, that is a
5683 bug.
5684
5685 @item
5686 If you are an experienced user of binary utilities, your suggestions for
5687 improvement are welcome in any case.
5688 @end itemize
5689
5690 @node Bug Reporting
5691 @section How to Report Bugs
5692 @cindex bug reports
5693 @cindex bugs, reporting
5694
5695 A number of companies and individuals offer support for @sc{gnu}
5696 products. If you obtained the binary utilities from a support
5697 organization, we recommend you contact that organization first.
5698
5699 You can find contact information for many support companies and
5700 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5701 distribution.
5702
5703 @ifset BUGURL
5704 In any event, we also recommend that you send bug reports for the binary
5705 utilities to @value{BUGURL}.
5706 @end ifset
5707
5708 The fundamental principle of reporting bugs usefully is this:
5709 @strong{report all the facts}. If you are not sure whether to state a
5710 fact or leave it out, state it!
5711
5712 Often people omit facts because they think they know what causes the
5713 problem and assume that some details do not matter. Thus, you might
5714 assume that the name of a file you use in an example does not matter.
5715 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5716 a stray memory reference which happens to fetch from the location where
5717 that pathname is stored in memory; perhaps, if the pathname were
5718 different, the contents of that location would fool the utility into
5719 doing the right thing despite the bug. Play it safe and give a
5720 specific, complete example. That is the easiest thing for you to do,
5721 and the most helpful.
5722
5723 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5724 it is new to us. Therefore, always write your bug reports on the assumption
5725 that the bug has not been reported previously.
5726
5727 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5728 bell?'' This cannot help us fix a bug, so it is basically useless. We
5729 respond by asking for enough details to enable us to investigate.
5730 You might as well expedite matters by sending them to begin with.
5731
5732 To enable us to fix the bug, you should include all these things:
5733
5734 @itemize @bullet
5735 @item
5736 The version of the utility. Each utility announces it if you start it
5737 with the @option{--version} argument.
5738
5739 Without this, we will not know whether there is any point in looking for
5740 the bug in the current version of the binary utilities.
5741
5742 @item
5743 Any patches you may have applied to the source, including any patches
5744 made to the @code{BFD} library.
5745
5746 @item
5747 The type of machine you are using, and the operating system name and
5748 version number.
5749
5750 @item
5751 What compiler (and its version) was used to compile the utilities---e.g.
5752 ``@code{gcc-2.7}''.
5753
5754 @item
5755 The command arguments you gave the utility to observe the bug. To
5756 guarantee you will not omit something important, list them all. A copy
5757 of the Makefile (or the output from make) is sufficient.
5758
5759 If we were to try to guess the arguments, we would probably guess wrong
5760 and then we might not encounter the bug.
5761
5762 @item
5763 A complete input file, or set of input files, that will reproduce the
5764 bug. If the utility is reading an object file or files, then it is
5765 generally most helpful to send the actual object files.
5766
5767 If the source files were produced exclusively using @sc{gnu} programs
5768 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5769 may be OK to send the source files rather than the object files. In
5770 this case, be sure to say exactly what version of @command{gcc}, or
5771 whatever, was used to produce the object files. Also say how
5772 @command{gcc}, or whatever, was configured.
5773
5774 @item
5775 A description of what behavior you observe that you believe is
5776 incorrect. For example, ``It gets a fatal signal.''
5777
5778 Of course, if the bug is that the utility gets a fatal signal, then we
5779 will certainly notice it. But if the bug is incorrect output, we might
5780 not notice unless it is glaringly wrong. You might as well not give us
5781 a chance to make a mistake.
5782
5783 Even if the problem you experience is a fatal signal, you should still
5784 say so explicitly. Suppose something strange is going on, such as your
5785 copy of the utility is out of sync, or you have encountered a bug in
5786 the C library on your system. (This has happened!) Your copy might
5787 crash and ours would not. If you told us to expect a crash, then when
5788 ours fails to crash, we would know that the bug was not happening for
5789 us. If you had not told us to expect a crash, then we would not be able
5790 to draw any conclusion from our observations.
5791
5792 @item
5793 If you wish to suggest changes to the source, send us context diffs, as
5794 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5795 option. Always send diffs from the old file to the new file. If you
5796 wish to discuss something in the @command{ld} source, refer to it by
5797 context, not by line number.
5798
5799 The line numbers in our development sources will not match those in your
5800 sources. Your line numbers would convey no useful information to us.
5801 @end itemize
5802
5803 Here are some things that are not necessary:
5804
5805 @itemize @bullet
5806 @item
5807 A description of the envelope of the bug.
5808
5809 Often people who encounter a bug spend a lot of time investigating
5810 which changes to the input file will make the bug go away and which
5811 changes will not affect it.
5812
5813 This is often time consuming and not very useful, because the way we
5814 will find the bug is by running a single example under the debugger
5815 with breakpoints, not by pure deduction from a series of examples.
5816 We recommend that you save your time for something else.
5817
5818 Of course, if you can find a simpler example to report @emph{instead}
5819 of the original one, that is a convenience for us. Errors in the
5820 output will be easier to spot, running under the debugger will take
5821 less time, and so on.
5822
5823 However, simplification is not vital; if you do not want to do this,
5824 report the bug anyway and send us the entire test case you used.
5825
5826 @item
5827 A patch for the bug.
5828
5829 A patch for the bug does help us if it is a good one. But do not omit
5830 the necessary information, such as the test case, on the assumption that
5831 a patch is all we need. We might see problems with your patch and decide
5832 to fix the problem another way, or we might not understand it at all.
5833
5834 Sometimes with programs as complicated as the binary utilities it is
5835 very hard to construct an example that will make the program follow a
5836 certain path through the code. If you do not send us the example, we
5837 will not be able to construct one, so we will not be able to verify that
5838 the bug is fixed.
5839
5840 And if we cannot understand what bug you are trying to fix, or why your
5841 patch should be an improvement, we will not install it. A test case will
5842 help us to understand.
5843
5844 @item
5845 A guess about what the bug is or what it depends on.
5846
5847 Such guesses are usually wrong. Even we cannot guess right about such
5848 things without first using the debugger to find the facts.
5849 @end itemize
5850
5851 @node GNU Free Documentation License
5852 @appendix GNU Free Documentation License
5853
5854 @include fdl.texi
5855
5856 @node Binutils Index
5857 @unnumbered Binutils Index
5858
5859 @printindex cp
5860
5861 @bye