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1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
4 @finalout
5 @synindex ky cp
6
7 @c man begin INCLUDE
8 @include bfdver.texi
9 @c man end
10
11 @copying
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2022 Free Software Foundation, Inc.
14
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
21
22 @c man end
23 @end copying
24
25 @dircategory Software development
26 @direntry
27 * Binutils: (binutils). The GNU binary utilities.
28 @end direntry
29
30 @dircategory Individual utilities
31 @direntry
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nm: (binutils)nm. List symbols from object files.
38 * objcopy: (binutils)objcopy. Copy and translate object files.
39 * objdump: (binutils)objdump. Display information from object files.
40 * ranlib: (binutils)ranlib. Generate index to archive contents.
41 * readelf: (binutils)readelf. Display the contents of ELF format files.
42 * size: (binutils)size. List section sizes and total size.
43 * strings: (binutils)strings. List printable strings from files.
44 * strip: (binutils)strip. Discard symbols.
45 * elfedit: (binutils)elfedit. Update ELF header and property of ELF files.
46 * windmc: (binutils)windmc. Generator for Windows message resources.
47 * windres: (binutils)windres. Manipulate Windows resources.
48 @end direntry
49
50 @titlepage
51 @title The @sc{gnu} Binary Utilities
52 @ifset VERSION_PACKAGE
53 @subtitle @value{VERSION_PACKAGE}
54 @end ifset
55 @subtitle Version @value{VERSION}
56 @sp 1
57 @subtitle @value{UPDATED}
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
61 @page
62
63 @tex
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 Texinfo \texinfoversion\par }
66 @end tex
67
68 @vskip 0pt plus 1filll
69 @insertcopying
70 @end titlepage
71 @contents
72
73 @node Top
74 @top Introduction
75
76 @cindex version
77 This brief manual contains documentation for the @sc{gnu} binary
78 utilities
79 @ifset VERSION_PACKAGE
80 @value{VERSION_PACKAGE}
81 @end ifset
82 version @value{VERSION}:
83
84 @iftex
85 @table @code
86 @item ar
87 Create, modify, and extract from archives
88
89 @item nm
90 List symbols from object files
91
92 @item objcopy
93 Copy and translate object files
94
95 @item objdump
96 Display information from object files
97
98 @item ranlib
99 Generate index to archive contents
100
101 @item readelf
102 Display the contents of ELF format files.
103
104 @item size
105 List file section sizes and total size
106
107 @item strings
108 List printable strings from files
109
110 @item strip
111 Discard symbols
112
113 @item elfedit
114 Update the ELF header and program property of ELF files.
115
116 @item c++filt
117 Demangle encoded C++ symbols (on MS-DOS, this program is named
118 @code{cxxfilt})
119
120 @item addr2line
121 Convert addresses or symbol+offset into file names and line numbers
122
123 @item windres
124 Manipulate Windows resources
125
126 @item windmc
127 Generator for Windows message resources
128
129 @item dlltool
130 Create the files needed to build and use Dynamic Link Libraries
131 @end table
132 @end iftex
133
134 This document is distributed under the terms of the GNU Free
135 Documentation License version 1.3. A copy of the license is included
136 in the section entitled ``GNU Free Documentation License''.
137
138 @menu
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * size:: List section sizes and total size
145 * strings:: List printable strings from files
146 * strip:: Discard symbols
147 * c++filt:: Filter to demangle encoded C++ symbols
148 * cxxfilt: c++filt. MS-DOS name for c++filt
149 * addr2line:: Convert addresses or symbol+offset to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update ELF header and property of ELF files
155 * Common Options:: Command-line options for all utilities
156 * Selecting the Target System:: How these utilities determine the target
157 * debuginfod:: Using binutils with debuginfod
158 * Reporting Bugs:: Reporting Bugs
159 * GNU Free Documentation License:: GNU Free Documentation License
160 * Binutils Index:: Binutils Index
161 @end menu
162
163 @node ar
164 @chapter ar
165
166 @kindex ar
167 @cindex archives
168 @cindex collections of files
169
170 @c man title ar create, modify, and extract from archives
171
172 @smallexample
173 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
174 ar -M [ <mri-script ]
175 @end smallexample
176
177 @c man begin DESCRIPTION ar
178
179 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
180 archives. An @dfn{archive} is a single file holding a collection of
181 other files in a structure that makes it possible to retrieve
182 the original individual files (called @dfn{members} of the archive).
183
184 The original files' contents, mode (permissions), timestamp, owner, and
185 group are preserved in the archive, and can be restored on
186 extraction.
187
188 @cindex name length
189 @sc{gnu} @command{ar} can maintain archives whose members have names of any
190 length; however, depending on how @command{ar} is configured on your
191 system, a limit on member-name length may be imposed for compatibility
192 with archive formats maintained with other tools. If it exists, the
193 limit is often 15 characters (typical of formats related to a.out) or 16
194 characters (typical of formats related to coff).
195
196 @cindex libraries
197 @command{ar} is considered a binary utility because archives of this sort
198 are most often used as @dfn{libraries} holding commonly needed
199 subroutines. Since libraries often will depend on other libraries,
200 @command{ar} can also record the dependencies of a library when the
201 @option{--record-libdeps} option is specified.
202
203 @cindex symbol index
204 @command{ar} creates an index to the symbols defined in relocatable
205 object modules in the archive when you specify the modifier @samp{s}.
206 Once created, this index is updated in the archive whenever @command{ar}
207 makes a change to its contents (save for the @samp{q} update operation).
208 An archive with such an index speeds up linking to the library, and
209 allows routines in the library to call each other without regard to
210 their placement in the archive.
211
212 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
213 table. If an archive lacks the table, another form of @command{ar} called
214 @command{ranlib} can be used to add just the table.
215
216 @cindex thin archives
217 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
218 which contains a symbol index and references to the original copies
219 of the member files of the archive. This is useful for building
220 libraries for use within a local build tree, where the relocatable
221 objects are expected to remain available, and copying the contents of
222 each object would only waste time and space.
223
224 An archive can either be @emph{thin} or it can be normal. It cannot
225 be both at the same time. Once an archive is created its format
226 cannot be changed without first deleting it and then creating a new
227 archive in its place.
228
229 Thin archives are also @emph{flattened}, so that adding one thin
230 archive to another thin archive does not nest it, as would happen with
231 a normal archive. Instead the elements of the first archive are added
232 individually to the second archive.
233
234 The paths to the elements of the archive are stored relative to the
235 archive itself.
236
237 @cindex compatibility, @command{ar}
238 @cindex @command{ar} compatibility
239 @sc{gnu} @command{ar} is designed to be compatible with two different
240 facilities. You can control its activity using command-line options,
241 like the different varieties of @command{ar} on Unix systems; or, if you
242 specify the single command-line option @option{-M}, you can control it
243 with a script supplied via standard input, like the MRI ``librarian''
244 program.
245
246 @c man end
247
248 @menu
249 * ar cmdline:: Controlling @command{ar} on the command line
250 * ar scripts:: Controlling @command{ar} with a script
251 @end menu
252
253 @page
254 @node ar cmdline
255 @section Controlling @command{ar} on the Command Line
256
257 @smallexample
258 @c man begin SYNOPSIS ar
259 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@option{--thin}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
260 @c man end
261 @end smallexample
262
263 @cindex Unix compatibility, @command{ar}
264 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
265 arguments to execute: one keyletter specifying the @emph{operation}
266 (optionally accompanied by other keyletters specifying
267 @emph{modifiers}), and the archive name to act on.
268
269 Most operations can also accept further @var{member} arguments,
270 specifying particular files to operate on.
271
272 @c man begin OPTIONS ar
273
274 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
275 flags @var{mod} in any order, within the first command-line argument.
276
277 If you wish, you may begin the first command-line argument with a
278 dash.
279
280 @cindex operations on archive
281 The @var{p} keyletter specifies what operation to execute; it may be
282 any of the following, but you must specify only one of them:
283
284 @table @samp
285 @item d
286 @cindex deleting from archive
287 @emph{Delete} modules from the archive. Specify the names of modules to
288 be deleted as @var{member}@dots{}; the archive is untouched if you
289 specify no files to delete.
290
291 If you specify the @samp{v} modifier, @command{ar} lists each module
292 as it is deleted.
293
294 @item m
295 @cindex moving in archive
296 Use this operation to @emph{move} members in an archive.
297
298 The ordering of members in an archive can make a difference in how
299 programs are linked using the library, if a symbol is defined in more
300 than one member.
301
302 If no modifiers are used with @code{m}, any members you name in the
303 @var{member} arguments are moved to the @emph{end} of the archive;
304 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
305 specified place instead.
306
307 @item p
308 @cindex printing from archive
309 @emph{Print} the specified members of the archive, to the standard
310 output file. If the @samp{v} modifier is specified, show the member
311 name before copying its contents to standard output.
312
313 If you specify no @var{member} arguments, all the files in the archive are
314 printed.
315
316 @item q
317 @cindex quick append to archive
318 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
319 @var{archive}, without checking for replacement.
320
321 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
322 operation; new members are always placed at the end of the archive.
323
324 The modifier @samp{v} makes @command{ar} list each file as it is appended.
325
326 Since the point of this operation is speed, implementations of
327 @command{ar} have the option of not updating the archive's symbol
328 table if one exists. Too many different systems however assume that
329 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
330 rebuild the table even with a quick append.
331
332 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
333 synonym for @samp{r} - replacing already existing files in the
334 archive and appending new ones at the end.
335
336 @item r
337 @cindex replacement in archive
338 Insert the files @var{member}@dots{} into @var{archive} (with
339 @emph{replacement}). This operation differs from @samp{q} in that any
340 previously existing members are deleted if their names match those being
341 added.
342
343 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
344 displays an error message, and leaves undisturbed any existing members
345 of the archive matching that name.
346
347 By default, new members are added at the end of the file; but you may
348 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
349 placement relative to some existing member.
350
351 The modifier @samp{v} used with this operation elicits a line of
352 output for each file inserted, along with one of the letters @samp{a} or
353 @samp{r} to indicate whether the file was appended (no old member
354 deleted) or replaced.
355
356 @item s
357 @cindex ranlib
358 Add an index to the archive, or update it if it already exists. Note
359 this command is an exception to the rule that there can only be one
360 command letter, as it is possible to use it as either a command or a
361 modifier. In either case it does the same thing.
362
363 @item t
364 @cindex contents of archive
365 Display a @emph{table} listing the contents of @var{archive}, or those
366 of the files listed in @var{member}@dots{} that are present in the
367 archive. Normally only the member name is shown, but if the modifier
368 @samp{O} is specified, then the corresponding offset of the member is also
369 displayed. Finally, in order to see the modes (permissions), timestamp,
370 owner, group, and size the @samp{v} modifier should be included.
371
372 If you do not specify a @var{member}, all files in the archive
373 are listed.
374
375 @cindex repeated names in archive
376 @cindex name duplication in archive
377 If there is more than one file with the same name (say, @samp{fie}) in
378 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
379 first instance; to see them all, you must ask for a complete
380 listing---in our example, @samp{ar t b.a}.
381 @c WRS only; per Gumby, this is implementation-dependent, and in a more
382 @c recent case in fact works the other way.
383
384 @item x
385 @cindex extract from archive
386 @emph{Extract} members (named @var{member}) from the archive. You can
387 use the @samp{v} modifier with this operation, to request that
388 @command{ar} list each name as it extracts it.
389
390 If you do not specify a @var{member}, all files in the archive
391 are extracted.
392
393 Files cannot be extracted from a thin archive, and there are
394 restrictions on extracting from archives created with @option{P}: The
395 paths must not be absolute, may not contain @code{..}, and any
396 subdirectories in the paths must exist. If it is desired to avoid
397 these restrictions then used the @option{--output} option to specify
398 an output directory.
399 @end table
400
401 A number of modifiers (@var{mod}) may immediately follow the @var{p}
402 keyletter, to specify variations on an operation's behavior:
403
404 @table @samp
405 @item a
406 @cindex relative placement in archive
407 Add new files @emph{after} an existing member of the
408 archive. If you use the modifier @samp{a}, the name of an existing archive
409 member must be present as the @var{relpos} argument, before the
410 @var{archive} specification.
411
412 @item b
413 Add new files @emph{before} an existing member of the
414 archive. If you use the modifier @samp{b}, the name of an existing archive
415 member must be present as the @var{relpos} argument, before the
416 @var{archive} specification. (same as @samp{i}).
417
418 @item c
419 @cindex creating archives
420 @emph{Create} the archive. The specified @var{archive} is always
421 created if it did not exist, when you request an update. But a warning is
422 issued unless you specify in advance that you expect to create it, by
423 using this modifier.
424
425 @item D
426 @cindex deterministic archives
427 @kindex --enable-deterministic-archives
428 Operate in @emph{deterministic} mode. When adding files and the archive
429 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
430 for all files. When this option is used, if @command{ar} is used with
431 identical options and identical input files, multiple runs will create
432 identical output files regardless of the input files' owners, groups,
433 file modes, or modification times.
434
435 If @file{binutils} was configured with
436 @option{--enable-deterministic-archives}, then this mode is on by default.
437 It can be disabled with the @samp{U} modifier, below.
438
439 @item f
440 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
441 names of any length. This will cause it to create archives which are
442 not compatible with the native @command{ar} program on some systems. If
443 this is a concern, the @samp{f} modifier may be used to truncate file
444 names when putting them in the archive.
445
446 @item i
447 Insert new files @emph{before} an existing member of the
448 archive. If you use the modifier @samp{i}, the name of an existing archive
449 member must be present as the @var{relpos} argument, before the
450 @var{archive} specification. (same as @samp{b}).
451
452 @item l
453 @c This modifier was accepted but not used.
454 @c whaffor ar l modifier??? presumably compat; with
455 @c what???---doc@@cygnus.com, 25jan91
456 Specify dependencies of this library. The dependencies must immediately
457 follow this option character, must use the same syntax as the linker
458 command line, and must be specified within a single argument. I.e., if
459 multiple items are needed, they must be quoted to form a single command
460 line argument. For example @samp{L "-L/usr/local/lib -lmydep1 -lmydep2"}
461
462 @item N
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
466
467 @item o
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
472
473 @item O
474 @cindex offsets of files
475 Display member offsets inside the archive. Use together with the @samp{t}
476 option.
477
478 @item P
479 Use the full path name when matching or storing names in the archive.
480 Archives created with full path names are not POSIX compliant, and
481 thus may not work with tools other than up to date @sc{gnu} tools.
482 Modifying such archives with @sc{gnu} @command{ar} without using
483 @option{P} will remove the full path names unless the archive is a
484 thin archive. Note that @option{P} may be useful when adding files to
485 a thin archive since @option{r} without @option{P} ignores the path
486 when choosing which element to replace. Thus
487 @smallexample
488 ar rcST archive.a subdir/file1 subdir/file2 file1
489 @end smallexample
490 will result in the first @code{subdir/file1} being replaced with
491 @code{file1} from the current directory. Adding @option{P} will
492 prevent this replacement.
493
494 @item s
495 @cindex writing archive index
496 Write an object-file index into the archive, or update an existing one,
497 even if no other change is made to the archive. You may use this modifier
498 flag either with any operation, or alone. Running @samp{ar s} on an
499 archive is equivalent to running @samp{ranlib} on it.
500
501 @item S
502 @cindex not writing archive index
503 Do not generate an archive symbol table. This can speed up building a
504 large library in several steps. The resulting archive can not be used
505 with the linker. In order to build a symbol table, you must omit the
506 @samp{S} modifier on the last execution of @samp{ar}, or you must run
507 @samp{ranlib} on the archive.
508
509 @item T
510 Deprecated alias for @option{--thin}. @option{T} is not recommended because in
511 many ar implementations @option{T} has a different meaning, as specified by
512 X/Open System Interface.
513
514 @item u
515 @cindex updating an archive
516 Normally, @samp{ar r}@dots{} inserts all files
517 listed into the archive. If you would like to insert @emph{only} those
518 of the files you list that are newer than existing members of the same
519 names, use this modifier. The @samp{u} modifier is allowed only for the
520 operation @samp{r} (replace). In particular, the combination @samp{qu} is
521 not allowed, since checking the timestamps would lose any speed
522 advantage from the operation @samp{q}.
523
524 @item U
525 @cindex deterministic archives
526 @kindex --enable-deterministic-archives
527 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
528 of the @samp{D} modifier, above: added files and the archive index will
529 get their actual UID, GID, timestamp, and file mode values.
530
531 This is the default unless @file{binutils} was configured with
532 @option{--enable-deterministic-archives}.
533
534 @item v
535 This modifier requests the @emph{verbose} version of an operation. Many
536 operations display additional information, such as filenames processed,
537 when the modifier @samp{v} is appended.
538
539 @item V
540 This modifier shows the version number of @command{ar}.
541 @end table
542
543 The @command{ar} program also supports some command-line options which
544 are neither modifiers nor actions, but which do change its behaviour
545 in specific ways:
546
547 @table @samp
548 @item --help
549 Displays the list of command-line options supported by @command{ar}
550 and then exits.
551
552 @item --version
553 Displays the version information of @command{ar} and then exits.
554
555 @item -X32_64
556 @command{ar} ignores an initial option spelled @samp{-X32_64}, for
557 compatibility with AIX. The behaviour produced by this option is the
558 default for @sc{gnu} @command{ar}. @command{ar} does not support any
559 of the other @samp{-X} options; in particular, it does not support
560 @option{-X32} which is the default for AIX @command{ar}.
561
562 @item --plugin @var{name}
563 @cindex plugins
564 The optional command-line switch @option{--plugin @var{name}} causes
565 @command{ar} to load the plugin called @var{name} which adds support
566 for more file formats, including object files with link-time
567 optimization information.
568
569 This option is only available if the toolchain has been built with
570 plugin support enabled.
571
572 If @option{--plugin} is not provided, but plugin support has been
573 enabled then @command{ar} iterates over the files in
574 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
575 plugin that claims the object in question is used.
576
577 Please note that this plugin search directory is @emph{not} the one
578 used by @command{ld}'s @option{-plugin} option. In order to make
579 @command{ar} use the linker plugin it must be copied into the
580 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
581 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
582 based compilations it is called @file{LLVMgold.so}. The GCC plugin
583 is always backwards compatible with earlier versions, so it is
584 sufficient to just copy the newest one.
585
586 @item --target @var{target}
587 The optional command-line switch @option{--target @var{bfdname}}
588 specifies that the archive members are in an object code format
589 different from your system's default format. See
590 @xref{Target Selection}, for more information.
591
592 @item --output @var{dirname}
593 The @option{--output} option can be used to specify a path to a
594 directory into which archive members should be extracted. If this
595 option is not specified then the current directory will be used.
596
597 Note - although the presence of this option does imply a @option{x}
598 extraction operation that option must still be included on the command
599 line.
600
601 @item --record-libdeps @var{libdeps}
602 The @option{--record-libdeps} option is identical to the @option{l} modifier,
603 just handled in long form.
604
605 @item --thin
606 @cindex creating thin archive
607 Make the specified @var{archive} a @emph{thin} archive. If it already
608 exists and is a regular archive, the existing members must be present
609 in the same directory as @var{archive}.
610
611 @end table
612 @c man end
613
614 @ignore
615 @c man begin SEEALSO ar
616 nm(1), ranlib(1), and the Info entries for @file{binutils}.
617 @c man end
618 @end ignore
619
620 @node ar scripts
621 @section Controlling @command{ar} with a Script
622
623 @smallexample
624 ar -M [ <@var{script} ]
625 @end smallexample
626
627 @cindex MRI compatibility, @command{ar}
628 @cindex scripts, @command{ar}
629 If you use the single command-line option @samp{-M} with @command{ar}, you
630 can control its operation with a rudimentary command language. This
631 form of @command{ar} operates interactively if standard input is coming
632 directly from a terminal. During interactive use, @command{ar} prompts for
633 input (the prompt is @samp{AR >}), and continues executing even after
634 errors. If you redirect standard input to a script file, no prompts are
635 issued, and @command{ar} abandons execution (with a nonzero exit code)
636 on any error.
637
638 The @command{ar} command language is @emph{not} designed to be equivalent
639 to the command-line options; in fact, it provides somewhat less control
640 over archives. The only purpose of the command language is to ease the
641 transition to @sc{gnu} @command{ar} for developers who already have scripts
642 written for the MRI ``librarian'' program.
643
644 The syntax for the @command{ar} command language is straightforward:
645 @itemize @bullet
646 @item
647 commands are recognized in upper or lower case; for example, @code{LIST}
648 is the same as @code{list}. In the following descriptions, commands are
649 shown in upper case for clarity.
650
651 @item
652 a single command may appear on each line; it is the first word on the
653 line.
654
655 @item
656 empty lines are allowed, and have no effect.
657
658 @item
659 comments are allowed; text after either of the characters @samp{*}
660 or @samp{;} is ignored.
661
662 @item
663 Whenever you use a list of names as part of the argument to an @command{ar}
664 command, you can separate the individual names with either commas or
665 blanks. Commas are shown in the explanations below, for clarity.
666
667 @item
668 @samp{+} is used as a line continuation character; if @samp{+} appears
669 at the end of a line, the text on the following line is considered part
670 of the current command.
671 @end itemize
672
673 Here are the commands you can use in @command{ar} scripts, or when using
674 @command{ar} interactively. Three of them have special significance:
675
676 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
677 a temporary file required for most of the other commands.
678
679 @code{SAVE} commits the changes so far specified by the script. Prior
680 to @code{SAVE}, commands affect only the temporary copy of the current
681 archive.
682
683 @table @code
684 @item ADDLIB @var{archive}
685 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
686 Add all the contents of @var{archive} (or, if specified, each named
687 @var{module} from @var{archive}) to the current archive.
688
689 Requires prior use of @code{OPEN} or @code{CREATE}.
690
691 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
692 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
693 @c else like "ar q..."
694 Add each named @var{member} as a module in the current archive.
695
696 Requires prior use of @code{OPEN} or @code{CREATE}.
697
698 @item CLEAR
699 Discard the contents of the current archive, canceling the effect of
700 any operations since the last @code{SAVE}. May be executed (with no
701 effect) even if no current archive is specified.
702
703 @item CREATE @var{archive}
704 Creates an archive, and makes it the current archive (required for many
705 other commands). The new archive is created with a temporary name; it
706 is not actually saved as @var{archive} until you use @code{SAVE}.
707 You can overwrite existing archives; similarly, the contents of any
708 existing file named @var{archive} will not be destroyed until @code{SAVE}.
709
710 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
711 Delete each listed @var{module} from the current archive; equivalent to
712 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
713
714 Requires prior use of @code{OPEN} or @code{CREATE}.
715
716 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
717 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
718 List each named @var{module} present in @var{archive}. The separate
719 command @code{VERBOSE} specifies the form of the output: when verbose
720 output is off, output is like that of @samp{ar -t @var{archive}
721 @var{module}@dots{}}. When verbose output is on, the listing is like
722 @samp{ar -tv @var{archive} @var{module}@dots{}}.
723
724 Output normally goes to the standard output stream; however, if you
725 specify @var{outputfile} as a final argument, @command{ar} directs the
726 output to that file.
727
728 @item END
729 Exit from @command{ar}, with a @code{0} exit code to indicate successful
730 completion. This command does not save the output file; if you have
731 changed the current archive since the last @code{SAVE} command, those
732 changes are lost.
733
734 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
735 Extract each named @var{module} from the current archive, writing them
736 into the current directory as separate files. Equivalent to @samp{ar -x
737 @var{archive} @var{module}@dots{}}.
738
739 Requires prior use of @code{OPEN} or @code{CREATE}.
740
741 @ignore
742 @c FIXME Tokens but no commands???
743 @item FULLDIR
744
745 @item HELP
746 @end ignore
747
748 @item LIST
749 Display full contents of the current archive, in ``verbose'' style
750 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
751 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
752 enhancement, rather than present for MRI compatibility.)
753
754 Requires prior use of @code{OPEN} or @code{CREATE}.
755
756 @item OPEN @var{archive}
757 Opens an existing archive for use as the current archive (required for
758 many other commands). Any changes as the result of subsequent commands
759 will not actually affect @var{archive} until you next use @code{SAVE}.
760
761 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
762 In the current archive, replace each existing @var{module} (named in
763 the @code{REPLACE} arguments) from files in the current working directory.
764 To execute this command without errors, both the file, and the module in
765 the current archive, must exist.
766
767 Requires prior use of @code{OPEN} or @code{CREATE}.
768
769 @item VERBOSE
770 Toggle an internal flag governing the output from @code{DIRECTORY}.
771 When the flag is on, @code{DIRECTORY} output matches output from
772 @samp{ar -tv }@dots{}.
773
774 @item SAVE
775 Commit your changes to the current archive, and actually save it as a
776 file with the name specified in the last @code{CREATE} or @code{OPEN}
777 command.
778
779 Requires prior use of @code{OPEN} or @code{CREATE}.
780
781 @end table
782
783 @iftex
784 @node ld
785 @chapter ld
786 @cindex linker
787 @kindex ld
788 The @sc{gnu} linker @command{ld} is now described in a separate manual.
789 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
790 @end iftex
791
792 @node nm
793 @chapter nm
794 @cindex symbols
795 @kindex nm
796
797 @c man title nm list symbols from object files
798
799 @smallexample
800 @c man begin SYNOPSIS nm
801 nm [@option{-A}|@option{-o}|@option{--print-file-name}]
802 [@option{-a}|@option{--debug-syms}]
803 [@option{-B}|@option{--format=bsd}]
804 [@option{-C}|@option{--demangle}[=@var{style}]]
805 [@option{-D}|@option{--dynamic}]
806 [@option{-f}@var{format}|@option{--format=}@var{format}]
807 [@option{-g}|@option{--extern-only}]
808 [@option{-h}|@option{--help}]
809 [@option{--ifunc-chars=@var{CHARS}}]
810 [@option{-j}|@option{--format=just-symbols}]
811 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
812 [@option{-n}|@option{-v}|@option{--numeric-sort}]
813 [@option{-P}|@option{--portability}]
814 [@option{-p}|@option{--no-sort}]
815 [@option{-r}|@option{--reverse-sort}]
816 [@option{-S}|@option{--print-size}]
817 [@option{-s}|@option{--print-armap}]
818 [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
819 [@option{-u}|@option{--undefined-only}]
820 [@option{-U}|@option{--defined-only}]
821 [@option{-V}|@option{--version}]
822 [@option{-W}|@option{--no-weak}]
823 [@option{-X 32_64}]
824 [@option{--no-demangle}]
825 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
826 [@option{--plugin} @var{name}]
827 [@option{--size-sort}]
828 [@option{--special-syms}]
829 [@option{--synthetic}]
830 [@option{--target=}@var{bfdname}]
831 [@option{--unicode=}@var{method}]
832 [@option{--with-symbol-versions}]
833 [@option{--without-symbol-versions}]
834 [@var{objfile}@dots{}]
835 @c man end
836 @end smallexample
837
838 @c man begin DESCRIPTION nm
839 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
840 If no object files are listed as arguments, @command{nm} assumes the file
841 @file{a.out}.
842
843 For each symbol, @command{nm} shows:
844
845 @itemize @bullet
846 @item
847 The symbol value, in the radix selected by options (see below), or
848 hexadecimal by default.
849
850 @item
851 The symbol type. At least the following types are used; others are, as
852 well, depending on the object file format. If lowercase, the symbol is
853 usually local; if uppercase, the symbol is global (external). There
854 are however a few lowercase symbols that are shown for special global
855 symbols (@code{u}, @code{v} and @code{w}).
856
857 @c Some more detail on exactly what these symbol types are used for
858 @c would be nice.
859 @table @code
860 @item A
861 The symbol's value is absolute, and will not be changed by further
862 linking.
863
864 @item B
865 @itemx b
866 The symbol is in the BSS data section. This section typically
867 contains zero-initialized or uninitialized data, although the exact
868 behavior is system dependent.
869
870 @item C
871 @itemx c
872 The symbol is common. Common symbols are uninitialized data. When
873 linking, multiple common symbols may appear with the same name. If the
874 symbol is defined anywhere, the common symbols are treated as undefined
875 references.
876 @ifclear man
877 For more details on common symbols, see the discussion of
878 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
879 @end ifclear
880 The lower case @var{c} character is used when the symbol is in a
881 special section for small commons.
882
883 @item D
884 @itemx d
885 The symbol is in the initialized data section.
886
887 @item G
888 @itemx g
889 The symbol is in an initialized data section for small objects. Some
890 object file formats permit more efficient access to small data objects,
891 such as a global int variable as opposed to a large global array.
892
893 @item i
894 For PE format files this indicates that the symbol is in a section
895 specific to the implementation of DLLs.
896
897 For ELF format files this indicates that the symbol is an indirect
898 function. This is a GNU extension to the standard set of ELF symbol
899 types. It indicates a symbol which if referenced by a relocation does
900 not evaluate to its address, but instead must be invoked at runtime.
901 The runtime execution will then return the value to be used in the
902 relocation.
903
904 Note - the actual symbols display for GNU indirect symbols is
905 controlled by the @option{--ifunc-chars} command line option. If this
906 option has been provided then the first character in the string will
907 be used for global indirect function symbols. If the string contains
908 a second character then that will be used for local indirect function
909 symbols.
910
911 @item I
912 The symbol is an indirect reference to another symbol.
913
914 @item N
915 The symbol is a debugging symbol.
916
917 @item n
918 The symbol is in the read-only data section.
919
920 @item p
921 The symbol is in a stack unwind section.
922
923 @item R
924 @itemx r
925 The symbol is in a read only data section.
926
927 @item S
928 @itemx s
929 The symbol is in an uninitialized or zero-initialized data section
930 for small objects.
931
932 @item T
933 @itemx t
934 The symbol is in the text (code) section.
935
936 @item U
937 The symbol is undefined.
938
939 @item u
940 The symbol is a unique global symbol. This is a GNU extension to the
941 standard set of ELF symbol bindings. For such a symbol the dynamic linker
942 will make sure that in the entire process there is just one symbol with
943 this name and type in use.
944
945 @item V
946 @itemx v
947 The symbol is a weak object. When a weak defined symbol is linked with
948 a normal defined symbol, the normal defined symbol is used with no error.
949 When a weak undefined symbol is linked and the symbol is not defined,
950 the value of the weak symbol becomes zero with no error. On some
951 systems, uppercase indicates that a default value has been specified.
952
953 @item W
954 @itemx w
955 The symbol is a weak symbol that has not been specifically tagged as a
956 weak object symbol. When a weak defined symbol is linked with a normal
957 defined symbol, the normal defined symbol is used with no error.
958 When a weak undefined symbol is linked and the symbol is not defined,
959 the value of the symbol is determined in a system-specific manner without
960 error. On some systems, uppercase indicates that a default value has been
961 specified.
962
963 @item -
964 The symbol is a stabs symbol in an a.out object file. In this case, the
965 next values printed are the stabs other field, the stabs desc field, and
966 the stab type. Stabs symbols are used to hold debugging information.
967
968 @item ?
969 The symbol type is unknown, or object file format specific.
970 @end table
971
972 @item
973 The symbol name. If a symbol has version information associated with it,
974 then the version information is displayed as well. If the versioned
975 symbol is undefined or hidden from linker, the version string is displayed
976 as a suffix to the symbol name, preceded by an @@ character. For example
977 @samp{foo@@VER_1}. If the version is the default version to be used when
978 resolving unversioned references to the symbol, then it is displayed as a
979 suffix preceded by two @@ characters. For example @samp{foo@@@@VER_2}.
980 @end itemize
981
982 @c man end
983
984 @c man begin OPTIONS nm
985 The long and short forms of options, shown here as alternatives, are
986 equivalent.
987
988 @table @env
989 @item -A
990 @itemx -o
991 @itemx --print-file-name
992 @cindex input file name
993 @cindex file name
994 @cindex source file name
995 Precede each symbol by the name of the input file (or archive member)
996 in which it was found, rather than identifying the input file once only,
997 before all of its symbols.
998
999 @item -a
1000 @itemx --debug-syms
1001 @cindex debugging symbols
1002 Display all symbols, even debugger-only symbols; normally these are not
1003 listed.
1004
1005 @item -B
1006 @cindex @command{nm} format
1007 @cindex @command{nm} compatibility
1008 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
1009
1010 @item -C
1011 @itemx --demangle[=@var{style}]
1012 @cindex demangling in nm
1013 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1014 Besides removing any initial underscore prepended by the system, this
1015 makes C++ function names readable. Different compilers have different
1016 mangling styles. The optional demangling style argument can be used to
1017 choose an appropriate demangling style for your compiler. @xref{c++filt},
1018 for more information on demangling.
1019
1020 @item --no-demangle
1021 Do not demangle low-level symbol names. This is the default.
1022
1023 @item --recurse-limit
1024 @itemx --no-recurse-limit
1025 @itemx --recursion-limit
1026 @itemx --no-recursion-limit
1027 Enables or disables a limit on the amount of recursion performed
1028 whilst demangling strings. Since the name mangling formats allow for
1029 an infinite level of recursion it is possible to create strings whose
1030 decoding will exhaust the amount of stack space available on the host
1031 machine, triggering a memory fault. The limit tries to prevent this
1032 from happening by restricting recursion to 2048 levels of nesting.
1033
1034 The default is for this limit to be enabled, but disabling it may be
1035 necessary in order to demangle truly complicated names. Note however
1036 that if the recursion limit is disabled then stack exhaustion is
1037 possible and any bug reports about such an event will be rejected.
1038
1039 @item -D
1040 @itemx --dynamic
1041 @cindex dynamic symbols
1042 Display the dynamic symbols rather than the normal symbols. This is
1043 only meaningful for dynamic objects, such as certain types of shared
1044 libraries.
1045
1046 @item -f @var{format}
1047 @itemx --format=@var{format}
1048 @cindex @command{nm} format
1049 @cindex @command{nm} compatibility
1050 Use the output format @var{format}, which can be @code{bsd},
1051 @code{sysv}, @code{posix} or @code{just-symbols}. The default is @code{bsd}.
1052 Only the first character of @var{format} is significant; it can be
1053 either upper or lower case.
1054
1055 @item -g
1056 @itemx --extern-only
1057 @cindex external symbols
1058 Display only external symbols.
1059
1060 @item -h
1061 @itemx --help
1062 Show a summary of the options to @command{nm} and exit.
1063
1064 @item --ifunc-chars=@var{CHARS}
1065 When display GNU indirect function symbols @command{nm} will default
1066 to using the @code{i} character for both local indirect functions and
1067 global indirect functions. The @option{--ifunc-chars} option allows
1068 the user to specify a string containing one or two characters. The
1069 first character will be used for global indirect function symbols and
1070 the second character, if present, will be used for local indirect
1071 function symbols.
1072
1073 @item j
1074 The same as @option{--format=just-symbols}.
1075
1076 @item -l
1077 @itemx --line-numbers
1078 @cindex symbol line numbers
1079 For each symbol, use debugging information to try to find a filename and
1080 line number. For a defined symbol, look for the line number of the
1081 address of the symbol. For an undefined symbol, look for the line
1082 number of a relocation entry which refers to the symbol. If line number
1083 information can be found, print it after the other symbol information.
1084
1085 @item --inlines
1086 @cindex objdump inlines
1087 When option @option{-l} is active, if the address belongs to a
1088 function that was inlined, then this option causes the source
1089 information for all enclosing scopes back to the first non-inlined
1090 function to be printed as well. For example, if @code{main} inlines
1091 @code{callee1} which inlines @code{callee2}, and address is from
1092 @code{callee2}, the source information for @code{callee1} and @code{main}
1093 will also be printed.
1094
1095 @item -n
1096 @itemx -v
1097 @itemx --numeric-sort
1098 Sort symbols numerically by their addresses, rather than alphabetically
1099 by their names.
1100
1101 @item -p
1102 @itemx --no-sort
1103 @cindex sorting symbols
1104 Do not bother to sort the symbols in any order; print them in the order
1105 encountered.
1106
1107 @item -P
1108 @itemx --portability
1109 Use the POSIX.2 standard output format instead of the default format.
1110 Equivalent to @samp{-f posix}.
1111
1112 @item -r
1113 @itemx --reverse-sort
1114 Reverse the order of the sort (whether numeric or alphabetic); let the
1115 last come first.
1116
1117 @item -S
1118 @itemx --print-size
1119 Print both value and size of defined symbols for the @code{bsd} output style.
1120 This option has no effect for object formats that do not record symbol
1121 sizes, unless @samp{--size-sort} is also used in which case a
1122 calculated size is displayed.
1123
1124 @item -s
1125 @itemx --print-armap
1126 @cindex symbol index, listing
1127 When listing symbols from archive members, include the index: a mapping
1128 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1129 contain definitions for which names.
1130
1131 @item -t @var{radix}
1132 @itemx --radix=@var{radix}
1133 Use @var{radix} as the radix for printing the symbol values. It must be
1134 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1135
1136 @item -u
1137 @itemx --undefined-only
1138 @cindex external symbols
1139 @cindex undefined symbols
1140 Display only undefined symbols (those external to each object file).
1141 By default both defined and undefined symbols are displayed.
1142
1143 @item -U
1144 @itemx --defined-only
1145 @cindex external symbols
1146 @cindex undefined symbols
1147 Display only defined symbols for each object file.
1148 By default both defined and undefined symbols are displayed.
1149
1150 @item -V
1151 @itemx --version
1152 Show the version number of @command{nm} and exit.
1153
1154 @item -X
1155 This option is ignored for compatibility with the AIX version of
1156 @command{nm}. It takes one parameter which must be the string
1157 @option{32_64}. The default mode of AIX @command{nm} corresponds
1158 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1159
1160 @item --plugin @var{name}
1161 @cindex plugins
1162 Load the plugin called @var{name} to add support for extra target
1163 types. This option is only available if the toolchain has been built
1164 with plugin support enabled.
1165
1166 If @option{--plugin} is not provided, but plugin support has been
1167 enabled then @command{nm} iterates over the files in
1168 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1169 plugin that claims the object in question is used.
1170
1171 Please note that this plugin search directory is @emph{not} the one
1172 used by @command{ld}'s @option{-plugin} option. In order to make
1173 @command{nm} use the linker plugin it must be copied into the
1174 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1175 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1176 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1177 is always backwards compatible with earlier versions, so it is
1178 sufficient to just copy the newest one.
1179
1180 @item --size-sort
1181 Sort symbols by size. For ELF objects symbol sizes are read from the
1182 ELF, for other object types the symbol sizes are computed as the
1183 difference between the value of the symbol and the value of the symbol
1184 with the next higher value. If the @code{bsd} output format is used
1185 the size of the symbol is printed, rather than the value, and
1186 @samp{-S} must be used in order both size and value to be printed.
1187
1188 Note - this option does not work if @option{--undefined-only} has been
1189 enabled as undefined symbols have no size.
1190
1191 @item --special-syms
1192 Display symbols which have a target-specific special meaning. These
1193 symbols are usually used by the target for some special processing and
1194 are not normally helpful when included in the normal symbol lists.
1195 For example for ARM targets this option would skip the mapping symbols
1196 used to mark transitions between ARM code, THUMB code and data.
1197
1198 @item --synthetic
1199 Include synthetic symbols in the output. These are special symbols
1200 created by the linker for various purposes. They are not shown by
1201 default since they are not part of the binary's original source code.
1202
1203 @item --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
1204 Controls the display of UTF-8 encoded multibyte characters in strings.
1205 The default (@option{--unicode=default}) is to give them no special
1206 treatment. The @option{--unicode=locale} option displays the sequence
1207 in the current locale, which may or may not support them. The options
1208 @option{--unicode=hex} and @option{--unicode=invalid} display them as
1209 hex byte sequences enclosed by either angle brackets or curly braces.
1210
1211 The @option{--unicode=escape} option displays them as escape sequences
1212 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
1213 them as escape sequences highlighted in red (if supported by the
1214 output device). The colouring is intended to draw attention to the
1215 presence of unicode sequences where they might not be expected.
1216
1217 @item -W
1218 @itemx --no-weak
1219 Do not display weak symbols.
1220
1221 @item --with-symbol-versions
1222 @item --without-symbol-versions
1223 Enables or disables the display of symbol version information. The
1224 version string is displayed as a suffix to the symbol name, preceded
1225 by an @@ character. For example @samp{foo@@VER_1}. If the version is
1226 the default version to be used when resolving unversioned references
1227 to the symbol then it is displayed as a suffix preceded by two @@
1228 characters. For example @samp{foo@@@@VER_2}. By default, symbol
1229 version information is displayed.
1230
1231 @item --target=@var{bfdname}
1232 @cindex object code format
1233 Specify an object code format other than your system's default format.
1234 @xref{Target Selection}, for more information.
1235
1236 @end table
1237
1238 @c man end
1239
1240 @ignore
1241 @c man begin SEEALSO nm
1242 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1243 @c man end
1244 @end ignore
1245
1246 @node objcopy
1247 @chapter objcopy
1248
1249 @c man title objcopy copy and translate object files
1250
1251 @smallexample
1252 @c man begin SYNOPSIS objcopy
1253 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1254 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1255 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1256 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1257 [@option{-S}|@option{--strip-all}]
1258 [@option{-g}|@option{--strip-debug}]
1259 [@option{--strip-unneeded}]
1260 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1261 [@option{--keep-file-symbols}]
1262 [@option{--keep-section-symbols}]
1263 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1264 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1265 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1266 [@option{--localize-hidden}]
1267 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1268 [@option{--globalize-symbol=}@var{symbolname}]
1269 [@option{--globalize-symbols=}@var{filename}]
1270 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1271 [@option{-w}|@option{--wildcard}]
1272 [@option{-x}|@option{--discard-all}]
1273 [@option{-X}|@option{--discard-locals}]
1274 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1275 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1276 [@option{--interleave-width=}@var{width}]
1277 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1278 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1279 [@option{--keep-section=}@var{sectionpattern}]
1280 [@option{--remove-relocations=}@var{sectionpattern}]
1281 [@option{-p}|@option{--preserve-dates}]
1282 [@option{-D}|@option{--enable-deterministic-archives}]
1283 [@option{-U}|@option{--disable-deterministic-archives}]
1284 [@option{--debugging}]
1285 [@option{--gap-fill=}@var{val}]
1286 [@option{--pad-to=}@var{address}]
1287 [@option{--set-start=}@var{val}]
1288 [@option{--adjust-start=}@var{incr}]
1289 [@option{--change-addresses=}@var{incr}]
1290 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1291 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1292 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1293 [@option{--change-warnings}] [@option{--no-change-warnings}]
1294 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1295 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1296 [@option{--add-section} @var{sectionname}=@var{filename}]
1297 [@option{--dump-section} @var{sectionname}=@var{filename}]
1298 [@option{--update-section} @var{sectionname}=@var{filename}]
1299 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1300 [@option{--long-section-names} @{enable,disable,keep@}]
1301 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1302 [@option{--reverse-bytes=}@var{num}]
1303 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1304 [@option{--redefine-sym} @var{old}=@var{new}]
1305 [@option{--redefine-syms=}@var{filename}]
1306 [@option{--weaken}]
1307 [@option{--keep-symbols=}@var{filename}]
1308 [@option{--strip-symbols=}@var{filename}]
1309 [@option{--strip-unneeded-symbols=}@var{filename}]
1310 [@option{--keep-global-symbols=}@var{filename}]
1311 [@option{--localize-symbols=}@var{filename}]
1312 [@option{--weaken-symbols=}@var{filename}]
1313 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1314 [@option{--alt-machine-code=}@var{index}]
1315 [@option{--prefix-symbols=}@var{string}]
1316 [@option{--prefix-sections=}@var{string}]
1317 [@option{--prefix-alloc-sections=}@var{string}]
1318 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1319 [@option{--only-keep-debug}]
1320 [@option{--strip-dwo}]
1321 [@option{--extract-dwo}]
1322 [@option{--extract-symbol}]
1323 [@option{--writable-text}]
1324 [@option{--readonly-text}]
1325 [@option{--pure}]
1326 [@option{--impure}]
1327 [@option{--file-alignment=}@var{num}]
1328 [@option{--heap=}@var{size}]
1329 [@option{--image-base=}@var{address}]
1330 [@option{--section-alignment=}@var{num}]
1331 [@option{--stack=}@var{size}]
1332 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1333 [@option{--compress-debug-sections}]
1334 [@option{--decompress-debug-sections}]
1335 [@option{--elf-stt-common=@var{val}}]
1336 [@option{--merge-notes}]
1337 [@option{--no-merge-notes}]
1338 [@option{--verilog-data-width=@var{val}}]
1339 [@option{-v}|@option{--verbose}]
1340 [@option{-V}|@option{--version}]
1341 [@option{--help}] [@option{--info}]
1342 @var{infile} [@var{outfile}]
1343 @c man end
1344 @end smallexample
1345
1346 @c man begin DESCRIPTION objcopy
1347 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1348 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1349 read and write the object files. It can write the destination object
1350 file in a format different from that of the source object file. The
1351 exact behavior of @command{objcopy} is controlled by command-line options.
1352 Note that @command{objcopy} should be able to copy a fully linked file
1353 between any two formats. However, copying a relocatable object file
1354 between any two formats may not work as expected.
1355
1356 @command{objcopy} creates temporary files to do its translations and
1357 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1358 translation work; it has access to all the formats described in @sc{bfd}
1359 and thus is able to recognize most formats without being told
1360 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1361
1362 @command{objcopy} can be used to generate S-records by using an output
1363 target of @samp{srec} (e.g., use @samp{-O srec}).
1364
1365 @command{objcopy} can be used to generate a raw binary file by using an
1366 output target of @samp{binary} (e.g., use @option{-O binary}). When
1367 @command{objcopy} generates a raw binary file, it will essentially produce
1368 a memory dump of the contents of the input object file. All symbols and
1369 relocation information will be discarded. The memory dump will start at
1370 the load address of the lowest section copied into the output file.
1371
1372 When generating an S-record or a raw binary file, it may be helpful to
1373 use @option{-S} to remove sections containing debugging information. In
1374 some cases @option{-R} will be useful to remove sections which contain
1375 information that is not needed by the binary file.
1376
1377 Note---@command{objcopy} is not able to change the endianness of its input
1378 files. If the input format has an endianness (some formats do not),
1379 @command{objcopy} can only copy the inputs into file formats that have the
1380 same endianness or which have no endianness (e.g., @samp{srec}).
1381 (However, see the @option{--reverse-bytes} option.)
1382
1383 @c man end
1384
1385 @c man begin OPTIONS objcopy
1386
1387 @table @env
1388 @item @var{infile}
1389 @itemx @var{outfile}
1390 The input and output files, respectively.
1391 If you do not specify @var{outfile}, @command{objcopy} creates a
1392 temporary file and destructively renames the result with
1393 the name of @var{infile}.
1394
1395 @item -I @var{bfdname}
1396 @itemx --input-target=@var{bfdname}
1397 Consider the source file's object format to be @var{bfdname}, rather than
1398 attempting to deduce it. @xref{Target Selection}, for more information.
1399
1400 @item -O @var{bfdname}
1401 @itemx --output-target=@var{bfdname}
1402 Write the output file using the object format @var{bfdname}.
1403 @xref{Target Selection}, for more information.
1404
1405 @item -F @var{bfdname}
1406 @itemx --target=@var{bfdname}
1407 Use @var{bfdname} as the object format for both the input and the output
1408 file; i.e., simply transfer data from source to destination with no
1409 translation. @xref{Target Selection}, for more information.
1410
1411 @item -B @var{bfdarch}
1412 @itemx --binary-architecture=@var{bfdarch}
1413 Useful when transforming a architecture-less input file into an object file.
1414 In this case the output architecture can be set to @var{bfdarch}. This
1415 option will be ignored if the input file has a known @var{bfdarch}. You
1416 can access this binary data inside a program by referencing the special
1417 symbols that are created by the conversion process. These symbols are
1418 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1419 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1420 an object file and then access it in your code using these symbols.
1421
1422 @item -j @var{sectionpattern}
1423 @itemx --only-section=@var{sectionpattern}
1424 Copy only the indicated sections from the input file to the output file.
1425 This option may be given more than once. Note that using this option
1426 inappropriately may make the output file unusable. Wildcard
1427 characters are accepted in @var{sectionpattern}.
1428
1429 If the first character of @var{sectionpattern} is the exclamation
1430 point (!) then matching sections will not be copied, even if earlier
1431 use of @option{--only-section} on the same command line would
1432 otherwise copy it. For example:
1433
1434 @smallexample
1435 --only-section=.text.* --only-section=!.text.foo
1436 @end smallexample
1437
1438 will copy all sectinos matching '.text.*' but not the section
1439 '.text.foo'.
1440
1441 @item -R @var{sectionpattern}
1442 @itemx --remove-section=@var{sectionpattern}
1443 Remove any section matching @var{sectionpattern} from the output file.
1444 This option may be given more than once. Note that using this option
1445 inappropriately may make the output file unusable. Wildcard
1446 characters are accepted in @var{sectionpattern}. Using both the
1447 @option{-j} and @option{-R} options together results in undefined
1448 behaviour.
1449
1450 If the first character of @var{sectionpattern} is the exclamation
1451 point (!) then matching sections will not be removed even if an
1452 earlier use of @option{--remove-section} on the same command line
1453 would otherwise remove it. For example:
1454
1455 @smallexample
1456 --remove-section=.text.* --remove-section=!.text.foo
1457 @end smallexample
1458
1459 will remove all sections matching the pattern '.text.*', but will not
1460 remove the section '.text.foo'.
1461
1462 @item --keep-section=@var{sectionpattern}
1463 When removing sections from the output file, keep sections that match
1464 @var{sectionpattern}.
1465
1466 @item --remove-relocations=@var{sectionpattern}
1467 Remove non-dynamic relocations from the output file for any section
1468 matching @var{sectionpattern}. This option may be given more than
1469 once. Note that using this option inappropriately may make the output
1470 file unusable, and attempting to remove a dynamic relocation section
1471 such as @samp{.rela.plt} from an executable or shared library with
1472 @option{--remove-relocations=.plt} will not work. Wildcard characters
1473 are accepted in @var{sectionpattern}.
1474 For example:
1475
1476 @smallexample
1477 --remove-relocations=.text.*
1478 @end smallexample
1479
1480 will remove the relocations for all sections matching the pattern
1481 '.text.*'.
1482
1483 If the first character of @var{sectionpattern} is the exclamation
1484 point (!) then matching sections will not have their relocation
1485 removed even if an earlier use of @option{--remove-relocations} on the
1486 same command line would otherwise cause the relocations to be removed.
1487 For example:
1488
1489 @smallexample
1490 --remove-relocations=.text.* --remove-relocations=!.text.foo
1491 @end smallexample
1492
1493 will remove all relocations for sections matching the pattern
1494 '.text.*', but will not remove relocations for the section
1495 '.text.foo'.
1496
1497 @item -S
1498 @itemx --strip-all
1499 Do not copy relocation and symbol information from the source file.
1500 Also deletes debug sections.
1501
1502 @item -g
1503 @itemx --strip-debug
1504 Do not copy debugging symbols or sections from the source file.
1505
1506 @item --strip-unneeded
1507 Remove all symbols that are not needed for relocation processing in
1508 addition to debugging symbols and sections stripped by
1509 @option{--strip-debug}.
1510
1511 @item -K @var{symbolname}
1512 @itemx --keep-symbol=@var{symbolname}
1513 When stripping symbols, keep symbol @var{symbolname} even if it would
1514 normally be stripped. This option may be given more than once.
1515
1516 @item -N @var{symbolname}
1517 @itemx --strip-symbol=@var{symbolname}
1518 Do not copy symbol @var{symbolname} from the source file. This option
1519 may be given more than once.
1520
1521 @item --strip-unneeded-symbol=@var{symbolname}
1522 Do not copy symbol @var{symbolname} from the source file unless it is needed
1523 by a relocation. This option may be given more than once.
1524
1525 @item -G @var{symbolname}
1526 @itemx --keep-global-symbol=@var{symbolname}
1527 Keep only symbol @var{symbolname} global. Make all other symbols local
1528 to the file, so that they are not visible externally. This option may
1529 be given more than once. Note: this option cannot be used in
1530 conjunction with the @option{--globalize-symbol} or
1531 @option{--globalize-symbols} options.
1532
1533 @item --localize-hidden
1534 In an ELF object, mark all symbols that have hidden or internal visibility
1535 as local. This option applies on top of symbol-specific localization options
1536 such as @option{-L}.
1537
1538 @item -L @var{symbolname}
1539 @itemx --localize-symbol=@var{symbolname}
1540 Convert a global or weak symbol called @var{symbolname} into a local
1541 symbol, so that it is not visible externally. This option may be
1542 given more than once. Note - unique symbols are not converted.
1543
1544 @item -W @var{symbolname}
1545 @itemx --weaken-symbol=@var{symbolname}
1546 Make symbol @var{symbolname} weak. This option may be given more than once.
1547
1548 @item --globalize-symbol=@var{symbolname}
1549 Give symbol @var{symbolname} global scoping so that it is visible
1550 outside of the file in which it is defined. This option may be given
1551 more than once. Note: this option cannot be used in conjunction with
1552 the @option{-G} or @option{--keep-global-symbol} options.
1553
1554 @item -w
1555 @itemx --wildcard
1556 Permit regular expressions in @var{symbolname}s used in other command
1557 line options. The question mark (?), asterisk (*), backslash (\) and
1558 square brackets ([]) operators can be used anywhere in the symbol
1559 name. If the first character of the symbol name is the exclamation
1560 point (!) then the sense of the switch is reversed for that symbol.
1561 For example:
1562
1563 @smallexample
1564 -w -W !foo -W fo*
1565 @end smallexample
1566
1567 would cause objcopy to weaken all symbols that start with ``fo''
1568 except for the symbol ``foo''.
1569
1570 @item -x
1571 @itemx --discard-all
1572 Do not copy non-global symbols from the source file.
1573 @c FIXME any reason to prefer "non-global" to "local" here?
1574
1575 @item -X
1576 @itemx --discard-locals
1577 Do not copy compiler-generated local symbols.
1578 (These usually start with @samp{L} or @samp{.}.)
1579
1580 @item -b @var{byte}
1581 @itemx --byte=@var{byte}
1582 If interleaving has been enabled via the @option{--interleave} option
1583 then start the range of bytes to keep at the @var{byte}th byte.
1584 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1585 @var{breadth} is the value given by the @option{--interleave} option.
1586
1587 @item -i [@var{breadth}]
1588 @itemx --interleave[=@var{breadth}]
1589 Only copy a range out of every @var{breadth} bytes. (Header data is
1590 not affected). Select which byte in the range begins the copy with
1591 the @option{--byte} option. Select the width of the range with the
1592 @option{--interleave-width} option.
1593
1594 This option is useful for creating files to program @sc{rom}. It is
1595 typically used with an @code{srec} output target. Note that
1596 @command{objcopy} will complain if you do not specify the
1597 @option{--byte} option as well.
1598
1599 The default interleave breadth is 4, so with @option{--byte} set to 0,
1600 @command{objcopy} would copy the first byte out of every four bytes
1601 from the input to the output.
1602
1603 @item --interleave-width=@var{width}
1604 When used with the @option{--interleave} option, copy @var{width}
1605 bytes at a time. The start of the range of bytes to be copied is set
1606 by the @option{--byte} option, and the extent of the range is set with
1607 the @option{--interleave} option.
1608
1609 The default value for this option is 1. The value of @var{width} plus
1610 the @var{byte} value set by the @option{--byte} option must not exceed
1611 the interleave breadth set by the @option{--interleave} option.
1612
1613 This option can be used to create images for two 16-bit flashes interleaved
1614 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1615 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1616 commands. If the input was '12345678' then the outputs would be
1617 '1256' and '3478' respectively.
1618
1619 @item -p
1620 @itemx --preserve-dates
1621 Set the access and modification dates of the output file to be the same
1622 as those of the input file.
1623
1624 @item -D
1625 @itemx --enable-deterministic-archives
1626 @cindex deterministic archives
1627 @kindex --enable-deterministic-archives
1628 Operate in @emph{deterministic} mode. When copying archive members
1629 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1630 and use consistent file modes for all files.
1631
1632 If @file{binutils} was configured with
1633 @option{--enable-deterministic-archives}, then this mode is on by default.
1634 It can be disabled with the @samp{-U} option, below.
1635
1636 @item -U
1637 @itemx --disable-deterministic-archives
1638 @cindex deterministic archives
1639 @kindex --enable-deterministic-archives
1640 Do @emph{not} operate in @emph{deterministic} mode. This is the
1641 inverse of the @option{-D} option, above: when copying archive members
1642 and writing the archive index, use their actual UID, GID, timestamp,
1643 and file mode values.
1644
1645 This is the default unless @file{binutils} was configured with
1646 @option{--enable-deterministic-archives}.
1647
1648 @item --debugging
1649 Convert debugging information, if possible. This is not the default
1650 because only certain debugging formats are supported, and the
1651 conversion process can be time consuming.
1652
1653 @item --gap-fill @var{val}
1654 Fill gaps between sections with @var{val}. This operation applies to
1655 the @emph{load address} (LMA) of the sections. It is done by increasing
1656 the size of the section with the lower address, and filling in the extra
1657 space created with @var{val}.
1658
1659 @item --pad-to @var{address}
1660 Pad the output file up to the load address @var{address}. This is
1661 done by increasing the size of the last section. The extra space is
1662 filled in with the value specified by @option{--gap-fill} (default zero).
1663
1664 @item --set-start @var{val}
1665 Set the start address (also known as the entry address) of the new
1666 file to @var{val}. Not all object file formats support setting the
1667 start address.
1668
1669 @item --change-start @var{incr}
1670 @itemx --adjust-start @var{incr}
1671 @cindex changing start address
1672 Change the start address (also known as the entry address) by adding
1673 @var{incr}. Not all object file formats support setting the start
1674 address.
1675
1676 @item --change-addresses @var{incr}
1677 @itemx --adjust-vma @var{incr}
1678 @cindex changing object addresses
1679 Change the VMA and LMA addresses of all sections, as well as the start
1680 address, by adding @var{incr}. Some object file formats do not permit
1681 section addresses to be changed arbitrarily. Note that this does not
1682 relocate the sections; if the program expects sections to be loaded at a
1683 certain address, and this option is used to change the sections such
1684 that they are loaded at a different address, the program may fail.
1685
1686 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1687 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1688 @cindex changing section address
1689 Set or change both the VMA address and the LMA address of any section
1690 matching @var{sectionpattern}. If @samp{=} is used, the section
1691 address is set to @var{val}. Otherwise, @var{val} is added to or
1692 subtracted from the section address. See the comments under
1693 @option{--change-addresses}, above. If @var{sectionpattern} does not
1694 match any sections in the input file, a warning will be issued, unless
1695 @option{--no-change-warnings} is used.
1696
1697 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1698 @cindex changing section LMA
1699 Set or change the LMA address of any sections matching
1700 @var{sectionpattern}. The LMA address is the address where the
1701 section will be loaded into memory at program load time. Normally
1702 this is the same as the VMA address, which is the address of the
1703 section at program run time, but on some systems, especially those
1704 where a program is held in ROM, the two can be different. If @samp{=}
1705 is used, the section address is set to @var{val}. Otherwise,
1706 @var{val} is added to or subtracted from the section address. See the
1707 comments under @option{--change-addresses}, above. If
1708 @var{sectionpattern} does not match any sections in the input file, a
1709 warning will be issued, unless @option{--no-change-warnings} is used.
1710
1711 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1712 @cindex changing section VMA
1713 Set or change the VMA address of any section matching
1714 @var{sectionpattern}. The VMA address is the address where the
1715 section will be located once the program has started executing.
1716 Normally this is the same as the LMA address, which is the address
1717 where the section will be loaded into memory, but on some systems,
1718 especially those where a program is held in ROM, the two can be
1719 different. If @samp{=} is used, the section address is set to
1720 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1721 section address. See the comments under @option{--change-addresses},
1722 above. If @var{sectionpattern} does not match any sections in the
1723 input file, a warning will be issued, unless
1724 @option{--no-change-warnings} is used.
1725
1726 @item --change-warnings
1727 @itemx --adjust-warnings
1728 If @option{--change-section-address} or @option{--change-section-lma} or
1729 @option{--change-section-vma} is used, and the section pattern does not
1730 match any sections, issue a warning. This is the default.
1731
1732 @item --no-change-warnings
1733 @itemx --no-adjust-warnings
1734 Do not issue a warning if @option{--change-section-address} or
1735 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1736 if the section pattern does not match any sections.
1737
1738 @item --set-section-flags @var{sectionpattern}=@var{flags}
1739 Set the flags for any sections matching @var{sectionpattern}. The
1740 @var{flags} argument is a comma separated string of flag names. The
1741 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1742 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1743 @samp{exclude}, @samp{share}, and @samp{debug}. You can set the
1744 @samp{contents} flag for a section which does not have contents, but it
1745 is not meaningful to clear the @samp{contents} flag of a section which
1746 does have contents--just remove the section instead. Not all flags are
1747 meaningful for all object file formats. In particular the
1748 @samp{share} flag is only meaningful for COFF format files and not for
1749 ELF format files.
1750
1751 @item --set-section-alignment @var{sectionpattern}=@var{align}
1752 Set the alignment for any sections matching @var{sectionpattern}.
1753 @var{align} specifies the alignment in bytes and must be a power of
1754 two, i.e. 1, 2, 4, 8@dots{}.
1755
1756 @item --add-section @var{sectionname}=@var{filename}
1757 Add a new section named @var{sectionname} while copying the file. The
1758 contents of the new section are taken from the file @var{filename}. The
1759 size of the section will be the size of the file. This option only
1760 works on file formats which can support sections with arbitrary names.
1761 Note - it may be necessary to use the @option{--set-section-flags}
1762 option to set the attributes of the newly created section.
1763
1764 @item --dump-section @var{sectionname}=@var{filename}
1765 Place the contents of section named @var{sectionname} into the file
1766 @var{filename}, overwriting any contents that may have been there
1767 previously. This option is the inverse of @option{--add-section}.
1768 This option is similar to the @option{--only-section} option except
1769 that it does not create a formatted file, it just dumps the contents
1770 as raw binary data, without applying any relocations. The option can
1771 be specified more than once.
1772
1773 @item --update-section @var{sectionname}=@var{filename}
1774 Replace the existing contents of a section named @var{sectionname}
1775 with the contents of file @var{filename}. The size of the section
1776 will be adjusted to the size of the file. The section flags for
1777 @var{sectionname} will be unchanged. For ELF format files the section
1778 to segment mapping will also remain unchanged, something which is not
1779 possible using @option{--remove-section} followed by
1780 @option{--add-section}. The option can be specified more than once.
1781
1782 Note - it is possible to use @option{--rename-section} and
1783 @option{--update-section} to both update and rename a section from one
1784 command line. In this case, pass the original section name to
1785 @option{--update-section}, and the original and new section names to
1786 @option{--rename-section}.
1787
1788 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1789 Add a new symbol named @var{name} while copying the file. This option may be
1790 specified multiple times. If the @var{section} is given, the symbol will be
1791 associated with and relative to that section, otherwise it will be an ABS
1792 symbol. Specifying an undefined section will result in a fatal error. There
1793 is no check for the value, it will be taken as specified. Symbol flags can
1794 be specified and not all flags will be meaningful for all object file
1795 formats. By default, the symbol will be global. The special flag
1796 'before=@var{othersym}' will insert the new symbol in front of the specified
1797 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1798 symbol table in the order they appear.
1799
1800 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1801 Rename a section from @var{oldname} to @var{newname}, optionally
1802 changing the section's flags to @var{flags} in the process. This has
1803 the advantage over using a linker script to perform the rename in that
1804 the output stays as an object file and does not become a linked
1805 executable. This option accepts the same set of flags as the
1806 @option{--sect-section-flags} option.
1807
1808 This option is particularly helpful when the input format is binary,
1809 since this will always create a section called .data. If for example,
1810 you wanted instead to create a section called .rodata containing binary
1811 data you could use the following command line to achieve it:
1812
1813 @smallexample
1814 objcopy -I binary -O <output_format> -B <architecture> \
1815 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1816 <input_binary_file> <output_object_file>
1817 @end smallexample
1818
1819 @item --long-section-names @{enable,disable,keep@}
1820 Controls the handling of long section names when processing @code{COFF}
1821 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1822 is to preserve long section names if any are present in the input file.
1823 The @samp{enable} and @samp{disable} options forcibly enable or disable
1824 the use of long section names in the output object; when @samp{disable}
1825 is in effect, any long section names in the input object will be truncated.
1826 The @samp{enable} option will only emit long section names if any are
1827 present in the inputs; this is mostly the same as @samp{keep}, but it
1828 is left undefined whether the @samp{enable} option might force the
1829 creation of an empty string table in the output file.
1830
1831 @item --change-leading-char
1832 Some object file formats use special characters at the start of
1833 symbols. The most common such character is underscore, which compilers
1834 often add before every symbol. This option tells @command{objcopy} to
1835 change the leading character of every symbol when it converts between
1836 object file formats. If the object file formats use the same leading
1837 character, this option has no effect. Otherwise, it will add a
1838 character, or remove a character, or change a character, as
1839 appropriate.
1840
1841 @item --remove-leading-char
1842 If the first character of a global symbol is a special symbol leading
1843 character used by the object file format, remove the character. The
1844 most common symbol leading character is underscore. This option will
1845 remove a leading underscore from all global symbols. This can be useful
1846 if you want to link together objects of different file formats with
1847 different conventions for symbol names. This is different from
1848 @option{--change-leading-char} because it always changes the symbol name
1849 when appropriate, regardless of the object file format of the output
1850 file.
1851
1852 @item --reverse-bytes=@var{num}
1853 Reverse the bytes in a section with output contents. A section length must
1854 be evenly divisible by the value given in order for the swap to be able to
1855 take place. Reversing takes place before the interleaving is performed.
1856
1857 This option is used typically in generating ROM images for problematic
1858 target systems. For example, on some target boards, the 32-bit words
1859 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1860 regardless of the CPU byte order. Depending on the programming model, the
1861 endianness of the ROM may need to be modified.
1862
1863 Consider a simple file with a section containing the following eight
1864 bytes: @code{12345678}.
1865
1866 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1867 output file would be ordered @code{21436587}.
1868
1869 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1870 output file would be ordered @code{43218765}.
1871
1872 By using @samp{--reverse-bytes=2} for the above example, followed by
1873 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1874 output file would be ordered @code{34127856}.
1875
1876 @item --srec-len=@var{ival}
1877 Meaningful only for srec output. Set the maximum length of the Srecords
1878 being produced to @var{ival}. This length covers both address, data and
1879 crc fields.
1880
1881 @item --srec-forceS3
1882 Meaningful only for srec output. Avoid generation of S1/S2 records,
1883 creating S3-only record format.
1884
1885 @item --redefine-sym @var{old}=@var{new}
1886 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1887 when one is trying link two things together for which you have no
1888 source, and there are name collisions.
1889
1890 @item --redefine-syms=@var{filename}
1891 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1892 listed in the file @var{filename}. @var{filename} is simply a flat file,
1893 with one symbol pair per line. Line comments may be introduced by the hash
1894 character. This option may be given more than once.
1895
1896 @item --weaken
1897 Change all global symbols in the file to be weak. This can be useful
1898 when building an object which will be linked against other objects using
1899 the @option{-R} option to the linker. This option is only effective when
1900 using an object file format which supports weak symbols.
1901
1902 @item --keep-symbols=@var{filename}
1903 Apply @option{--keep-symbol} option to each symbol listed in the file
1904 @var{filename}. @var{filename} is simply a flat file, with one symbol
1905 name per line. Line comments may be introduced by the hash character.
1906 This option may be given more than once.
1907
1908 @item --strip-symbols=@var{filename}
1909 Apply @option{--strip-symbol} option to each symbol listed in the file
1910 @var{filename}. @var{filename} is simply a flat file, with one symbol
1911 name per line. Line comments may be introduced by the hash character.
1912 This option may be given more than once.
1913
1914 @item --strip-unneeded-symbols=@var{filename}
1915 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1916 the file @var{filename}. @var{filename} is simply a flat file, with one
1917 symbol name per line. Line comments may be introduced by the hash
1918 character. This option may be given more than once.
1919
1920 @item --keep-global-symbols=@var{filename}
1921 Apply @option{--keep-global-symbol} option to each symbol listed in the
1922 file @var{filename}. @var{filename} is simply a flat file, with one
1923 symbol name per line. Line comments may be introduced by the hash
1924 character. This option may be given more than once.
1925
1926 @item --localize-symbols=@var{filename}
1927 Apply @option{--localize-symbol} option to each symbol listed in the file
1928 @var{filename}. @var{filename} is simply a flat file, with one symbol
1929 name per line. Line comments may be introduced by the hash character.
1930 This option may be given more than once.
1931
1932 @item --globalize-symbols=@var{filename}
1933 Apply @option{--globalize-symbol} option to each symbol listed in the file
1934 @var{filename}. @var{filename} is simply a flat file, with one symbol
1935 name per line. Line comments may be introduced by the hash character.
1936 This option may be given more than once. Note: this option cannot be
1937 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1938 options.
1939
1940 @item --weaken-symbols=@var{filename}
1941 Apply @option{--weaken-symbol} option to each symbol listed in the file
1942 @var{filename}. @var{filename} is simply a flat file, with one symbol
1943 name per line. Line comments may be introduced by the hash character.
1944 This option may be given more than once.
1945
1946 @item --alt-machine-code=@var{index}
1947 If the output architecture has alternate machine codes, use the
1948 @var{index}th code instead of the default one. This is useful in case
1949 a machine is assigned an official code and the tool-chain adopts the
1950 new code, but other applications still depend on the original code
1951 being used. For ELF based architectures if the @var{index}
1952 alternative does not exist then the value is treated as an absolute
1953 number to be stored in the e_machine field of the ELF header.
1954
1955 @item --writable-text
1956 Mark the output text as writable. This option isn't meaningful for all
1957 object file formats.
1958
1959 @item --readonly-text
1960 Make the output text write protected. This option isn't meaningful for all
1961 object file formats.
1962
1963 @item --pure
1964 Mark the output file as demand paged. This option isn't meaningful for all
1965 object file formats.
1966
1967 @item --impure
1968 Mark the output file as impure. This option isn't meaningful for all
1969 object file formats.
1970
1971 @item --prefix-symbols=@var{string}
1972 Prefix all symbols in the output file with @var{string}.
1973
1974 @item --prefix-sections=@var{string}
1975 Prefix all section names in the output file with @var{string}.
1976
1977 @item --prefix-alloc-sections=@var{string}
1978 Prefix all the names of all allocated sections in the output file with
1979 @var{string}.
1980
1981 @item --add-gnu-debuglink=@var{path-to-file}
1982 Creates a .gnu_debuglink section which contains a reference to
1983 @var{path-to-file} and adds it to the output file. Note: the file at
1984 @var{path-to-file} must exist. Part of the process of adding the
1985 .gnu_debuglink section involves embedding a checksum of the contents
1986 of the debug info file into the section.
1987
1988 If the debug info file is built in one location but it is going to be
1989 installed at a later time into a different location then do not use
1990 the path to the installed location. The @option{--add-gnu-debuglink}
1991 option will fail because the installed file does not exist yet.
1992 Instead put the debug info file in the current directory and use the
1993 @option{--add-gnu-debuglink} option without any directory components,
1994 like this:
1995
1996 @smallexample
1997 objcopy --add-gnu-debuglink=foo.debug
1998 @end smallexample
1999
2000 At debug time the debugger will attempt to look for the separate debug
2001 info file in a set of known locations. The exact set of these
2002 locations varies depending upon the distribution being used, but it
2003 typically includes:
2004
2005 @table @code
2006
2007 @item * The same directory as the executable.
2008
2009 @item * A sub-directory of the directory containing the executable
2010 called .debug
2011
2012 @item * A global debug directory such as /usr/lib/debug.
2013 @end table
2014
2015 As long as the debug info file has been installed into one of these
2016 locations before the debugger is run everything should work
2017 correctly.
2018
2019 @item --keep-section-symbils
2020 When stripping a file, perhaps with @option{--strip-debug} or
2021 @option{--strip-unneeded}, retain any symbols specifying section names,
2022 which would otherwise get stripped.
2023
2024 @item --keep-file-symbols
2025 When stripping a file, perhaps with @option{--strip-debug} or
2026 @option{--strip-unneeded}, retain any symbols specifying source file names,
2027 which would otherwise get stripped.
2028
2029 @item --only-keep-debug
2030 Strip a file, removing contents of any sections that would not be
2031 stripped by @option{--strip-debug} and leaving the debugging sections
2032 intact. In ELF files, this preserves all note sections in the output.
2033
2034 Note - the section headers of the stripped sections are preserved,
2035 including their sizes, but the contents of the section are discarded.
2036 The section headers are preserved so that other tools can match up the
2037 debuginfo file with the real executable, even if that executable has
2038 been relocated to a different address space.
2039
2040 The intention is that this option will be used in conjunction with
2041 @option{--add-gnu-debuglink} to create a two part executable. One a
2042 stripped binary which will occupy less space in RAM and in a
2043 distribution and the second a debugging information file which is only
2044 needed if debugging abilities are required. The suggested procedure
2045 to create these files is as follows:
2046
2047 @enumerate
2048 @item Link the executable as normal. Assuming that it is called
2049 @code{foo} then...
2050 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2051 create a file containing the debugging info.
2052 @item Run @code{objcopy --strip-debug foo} to create a
2053 stripped executable.
2054 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2055 to add a link to the debugging info into the stripped executable.
2056 @end enumerate
2057
2058 Note---the choice of @code{.dbg} as an extension for the debug info
2059 file is arbitrary. Also the @code{--only-keep-debug} step is
2060 optional. You could instead do this:
2061
2062 @enumerate
2063 @item Link the executable as normal.
2064 @item Copy @code{foo} to @code{foo.full}
2065 @item Run @code{objcopy --strip-debug foo}
2066 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2067 @end enumerate
2068
2069 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2070 full executable. It does not have to be a file created by the
2071 @option{--only-keep-debug} switch.
2072
2073 Note---this switch is only intended for use on fully linked files. It
2074 does not make sense to use it on object files where the debugging
2075 information may be incomplete. Besides the gnu_debuglink feature
2076 currently only supports the presence of one filename containing
2077 debugging information, not multiple filenames on a one-per-object-file
2078 basis.
2079
2080 @item --strip-dwo
2081 Remove the contents of all DWARF .dwo sections, leaving the
2082 remaining debugging sections and all symbols intact.
2083 This option is intended for use by the compiler as part of
2084 the @option{-gsplit-dwarf} option, which splits debug information
2085 between the .o file and a separate .dwo file. The compiler
2086 generates all debug information in the same file, then uses
2087 the @option{--extract-dwo} option to copy the .dwo sections to
2088 the .dwo file, then the @option{--strip-dwo} option to remove
2089 those sections from the original .o file.
2090
2091 @item --extract-dwo
2092 Extract the contents of all DWARF .dwo sections. See the
2093 @option{--strip-dwo} option for more information.
2094
2095 @item --file-alignment @var{num}
2096 Specify the file alignment. Sections in the file will always begin at
2097 file offsets which are multiples of this number. This defaults to
2098 512.
2099 [This option is specific to PE targets.]
2100
2101 @item --heap @var{reserve}
2102 @itemx --heap @var{reserve},@var{commit}
2103 Specify the number of bytes of memory to reserve (and optionally commit)
2104 to be used as heap for this program.
2105 [This option is specific to PE targets.]
2106
2107 @item --image-base @var{value}
2108 Use @var{value} as the base address of your program or dll. This is
2109 the lowest memory location that will be used when your program or dll
2110 is loaded. To reduce the need to relocate and improve performance of
2111 your dlls, each should have a unique base address and not overlap any
2112 other dlls. The default is 0x400000 for executables, and 0x10000000
2113 for dlls.
2114 [This option is specific to PE targets.]
2115
2116 @item --section-alignment @var{num}
2117 Sets the section alignment field in the PE header. Sections in memory
2118 will always begin at addresses which are a multiple of this number.
2119 Defaults to 0x1000.
2120 [This option is specific to PE targets.]
2121
2122 @item --stack @var{reserve}
2123 @itemx --stack @var{reserve},@var{commit}
2124 Specify the number of bytes of memory to reserve (and optionally commit)
2125 to be used as stack for this program.
2126 [This option is specific to PE targets.]
2127
2128 @item --subsystem @var{which}
2129 @itemx --subsystem @var{which}:@var{major}
2130 @itemx --subsystem @var{which}:@var{major}.@var{minor}
2131 Specifies the subsystem under which your program will execute. The
2132 legal values for @var{which} are @code{native}, @code{windows},
2133 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2134 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2135 the subsystem version also. Numeric values are also accepted for
2136 @var{which}.
2137 [This option is specific to PE targets.]
2138
2139 @item --extract-symbol
2140 Keep the file's section flags and symbols but remove all section data.
2141 Specifically, the option:
2142
2143 @itemize
2144 @item removes the contents of all sections;
2145 @item sets the size of every section to zero; and
2146 @item sets the file's start address to zero.
2147 @end itemize
2148
2149 This option is used to build a @file{.sym} file for a VxWorks kernel.
2150 It can also be a useful way of reducing the size of a @option{--just-symbols}
2151 linker input file.
2152
2153 @item --compress-debug-sections
2154 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2155 ELF ABI. Note - if compression would actually make a section
2156 @emph{larger}, then it is not compressed.
2157
2158 @item --compress-debug-sections=none
2159 @itemx --compress-debug-sections=zlib
2160 @itemx --compress-debug-sections=zlib-gnu
2161 @itemx --compress-debug-sections=zlib-gabi
2162 @itemx --compress-debug-sections=zstd
2163 For ELF files, these options control how DWARF debug sections are
2164 compressed. @option{--compress-debug-sections=none} is equivalent
2165 to @option{--decompress-debug-sections}.
2166 @option{--compress-debug-sections=zlib} and
2167 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2168 @option{--compress-debug-sections}.
2169 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug sections
2170 using the obsoleted zlib-gnu format. The debug sections are renamed to begin
2171 with @samp{.zdebug}.
2172 @option{--compress-debug-sections=zstd} compresses DWARF debug
2173 sections using zstd. Note - if compression would actually make a section
2174 @emph{larger}, then it is not compressed nor renamed.
2175
2176 @item --decompress-debug-sections
2177 Decompress DWARF debug sections. For a @samp{.zdebug} section, the original
2178 name is restored.
2179
2180 @item --elf-stt-common=yes
2181 @itemx --elf-stt-common=no
2182 For ELF files, these options control whether common symbols should be
2183 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2184 @option{--elf-stt-common=yes} converts common symbol type to
2185 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2186 type to @code{STT_OBJECT}.
2187
2188 @item --merge-notes
2189 @itemx --no-merge-notes
2190 For ELF files, attempt (or do not attempt) to reduce the size of any
2191 SHT_NOTE type sections by removing duplicate notes.
2192
2193 @item -V
2194 @itemx --version
2195 Show the version number of @command{objcopy}.
2196
2197 @item --verilog-data-width=@var{bytes}
2198 For Verilog output, this options controls the number of bytes
2199 converted for each output data element. The input target controls the
2200 endianness of the conversion.
2201
2202 @item -v
2203 @itemx --verbose
2204 Verbose output: list all object files modified. In the case of
2205 archives, @samp{objcopy -V} lists all members of the archive.
2206
2207 @item --help
2208 Show a summary of the options to @command{objcopy}.
2209
2210 @item --info
2211 Display a list showing all architectures and object formats available.
2212 @end table
2213
2214 @c man end
2215
2216 @ignore
2217 @c man begin SEEALSO objcopy
2218 ld(1), objdump(1), and the Info entries for @file{binutils}.
2219 @c man end
2220 @end ignore
2221
2222 @node objdump
2223 @chapter objdump
2224
2225 @cindex object file information
2226 @kindex objdump
2227
2228 @c man title objdump display information from object files
2229
2230 @smallexample
2231 @c man begin SYNOPSIS objdump
2232 objdump [@option{-a}|@option{--archive-headers}]
2233 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2234 [@option{-C}|@option{--demangle}[=@var{style}] ]
2235 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2236 [@option{-D}|@option{--disassemble-all}]
2237 [@option{-z}|@option{--disassemble-zeroes}]
2238 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2239 [@option{-f}|@option{--file-headers}]
2240 [@option{-F}|@option{--file-offsets}]
2241 [@option{--file-start-context}]
2242 [@option{-g}|@option{--debugging}]
2243 [@option{-e}|@option{--debugging-tags}]
2244 [@option{-h}|@option{--section-headers}|@option{--headers}]
2245 [@option{-i}|@option{--info}]
2246 [@option{-j} @var{section}|@option{--section=}@var{section}]
2247 [@option{-l}|@option{--line-numbers}]
2248 [@option{-S}|@option{--source}]
2249 [@option{--source-comment}[=@var{text}]]
2250 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2251 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2252 [@option{-p}|@option{--private-headers}]
2253 [@option{-P} @var{options}|@option{--private=}@var{options}]
2254 [@option{-r}|@option{--reloc}]
2255 [@option{-R}|@option{--dynamic-reloc}]
2256 [@option{-s}|@option{--full-contents}]
2257 [@option{-W[lLiaprmfFsoORtUuTgAck]}|
2258 @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]]
2259 [@option{-WK}|@option{--dwarf=follow-links}]
2260 [@option{-WN}|@option{--dwarf=no-follow-links}]
2261 [@option{-wD}|@option{--dwarf=use-debuginfod}]
2262 [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
2263 [@option{-L}|@option{--process-links}]
2264 [@option{--ctf=}@var{section}]
2265 [@option{--sframe=}@var{section}]
2266 [@option{-G}|@option{--stabs}]
2267 [@option{-t}|@option{--syms}]
2268 [@option{-T}|@option{--dynamic-syms}]
2269 [@option{-x}|@option{--all-headers}]
2270 [@option{-w}|@option{--wide}]
2271 [@option{--start-address=}@var{address}]
2272 [@option{--stop-address=}@var{address}]
2273 [@option{--no-addresses}]
2274 [@option{--prefix-addresses}]
2275 [@option{--[no-]show-raw-insn}]
2276 [@option{--adjust-vma=}@var{offset}]
2277 [@option{--show-all-symbols}]
2278 [@option{--dwarf-depth=@var{n}}]
2279 [@option{--dwarf-start=@var{n}}]
2280 [@option{--ctf-parent=}@var{section}]
2281 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2282 [@option{--special-syms}]
2283 [@option{--prefix=}@var{prefix}]
2284 [@option{--prefix-strip=}@var{level}]
2285 [@option{--insn-width=}@var{width}]
2286 [@option{--visualize-jumps[=color|=extended-color|=off]}
2287 [@option{--disassembler-color=[off|terminal|on|extended]}
2288 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
2289 [@option{-V}|@option{--version}]
2290 [@option{-H}|@option{--help}]
2291 @var{objfile}@dots{}
2292 @c man end
2293 @end smallexample
2294
2295 @c man begin DESCRIPTION objdump
2296
2297 @command{objdump} displays information about one or more object files.
2298 The options control what particular information to display. This
2299 information is mostly useful to programmers who are working on the
2300 compilation tools, as opposed to programmers who just want their
2301 program to compile and work.
2302
2303 @var{objfile}@dots{} are the object files to be examined. When you
2304 specify archives, @command{objdump} shows information on each of the member
2305 object files.
2306
2307 @c man end
2308
2309 @c man begin OPTIONS objdump
2310
2311 The long and short forms of options, shown here as alternatives, are
2312 equivalent. At least one option from the list
2313 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2314
2315 @table @env
2316 @item -a
2317 @itemx --archive-header
2318 @cindex archive headers
2319 If any of the @var{objfile} files are archives, display the archive
2320 header information (in a format similar to @samp{ls -l}). Besides the
2321 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2322 the object file format of each archive member.
2323
2324 @item --adjust-vma=@var{offset}
2325 @cindex section addresses in objdump
2326 @cindex VMA in objdump
2327 When dumping information, first add @var{offset} to all the section
2328 addresses. This is useful if the section addresses do not correspond to
2329 the symbol table, which can happen when putting sections at particular
2330 addresses when using a format which can not represent section addresses,
2331 such as a.out.
2332
2333 @item -b @var{bfdname}
2334 @itemx --target=@var{bfdname}
2335 @cindex object code format
2336 Specify that the object-code format for the object files is
2337 @var{bfdname}. This option may not be necessary; @var{objdump} can
2338 automatically recognize many formats.
2339
2340 For example,
2341 @example
2342 objdump -b oasys -m vax -h fu.o
2343 @end example
2344 @noindent
2345 displays summary information from the section headers (@option{-h}) of
2346 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2347 file in the format produced by Oasys compilers. You can list the
2348 formats available with the @option{-i} option.
2349 @xref{Target Selection}, for more information.
2350
2351 @item -C
2352 @itemx --demangle[=@var{style}]
2353 @cindex demangling in objdump
2354 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2355 Besides removing any initial underscore prepended by the system, this
2356 makes C++ function names readable. Different compilers have different
2357 mangling styles. The optional demangling style argument can be used to
2358 choose an appropriate demangling style for your compiler. @xref{c++filt},
2359 for more information on demangling.
2360
2361 @item --recurse-limit
2362 @itemx --no-recurse-limit
2363 @itemx --recursion-limit
2364 @itemx --no-recursion-limit
2365 Enables or disables a limit on the amount of recursion performed
2366 whilst demangling strings. Since the name mangling formats allow for
2367 an infinite level of recursion it is possible to create strings whose
2368 decoding will exhaust the amount of stack space available on the host
2369 machine, triggering a memory fault. The limit tries to prevent this
2370 from happening by restricting recursion to 2048 levels of nesting.
2371
2372 The default is for this limit to be enabled, but disabling it may be
2373 necessary in order to demangle truly complicated names. Note however
2374 that if the recursion limit is disabled then stack exhaustion is
2375 possible and any bug reports about such an event will be rejected.
2376
2377 @item -g
2378 @itemx --debugging
2379 Display debugging information. This attempts to parse STABS
2380 debugging format information stored in the file and print it out using
2381 a C like syntax. If no STABS debugging was found this option
2382 falls back on the @option{-W} option to print any DWARF information in
2383 the file.
2384
2385 @item -e
2386 @itemx --debugging-tags
2387 Like @option{-g}, but the information is generated in a format compatible
2388 with ctags tool.
2389
2390 @item -d
2391 @itemx --disassemble
2392 @itemx --disassemble=@var{symbol}
2393 @cindex disassembling object code
2394 @cindex machine instructions
2395 Display the assembler mnemonics for the machine instructions from the
2396 input file. This option only disassembles those sections which are
2397 expected to contain instructions. If the optional @var{symbol}
2398 argument is given, then display the assembler mnemonics starting at
2399 @var{symbol}. If @var{symbol} is a function name then disassembly
2400 will stop at the end of the function, otherwise it will stop when the
2401 next symbol is encountered. If there are no matches for @var{symbol}
2402 then nothing will be displayed.
2403
2404 Note if the @option{--dwarf=follow-links} option is enabled
2405 then any symbol tables in linked debug info files will be read in and
2406 used when disassembling.
2407
2408 @item -D
2409 @itemx --disassemble-all
2410 Like @option{-d}, but disassemble the contents of all sections, not just
2411 those expected to contain instructions.
2412
2413 This option also has a subtle effect on the disassembly of
2414 instructions in code sections. When option @option{-d} is in effect
2415 objdump will assume that any symbols present in a code section occur
2416 on the boundary between instructions and it will refuse to disassemble
2417 across such a boundary. When option @option{-D} is in effect however
2418 this assumption is supressed. This means that it is possible for the
2419 output of @option{-d} and @option{-D} to differ if, for example, data
2420 is stored in code sections.
2421
2422 If the target is an ARM architecture this switch also has the effect
2423 of forcing the disassembler to decode pieces of data found in code
2424 sections as if they were instructions.
2425
2426 Note if the @option{--dwarf=follow-links} option is enabled
2427 then any symbol tables in linked debug info files will be read in and
2428 used when disassembling.
2429
2430 @item --no-addresses
2431 When disassembling, don't print addresses on each line or for symbols
2432 and relocation offsets. In combination with @option{--no-show-raw-insn}
2433 this may be useful for comparing compiler output.
2434
2435 @item --prefix-addresses
2436 When disassembling, print the complete address on each line. This is
2437 the older disassembly format.
2438
2439 @item -EB
2440 @itemx -EL
2441 @itemx --endian=@{big|little@}
2442 @cindex endianness
2443 @cindex disassembly endianness
2444 Specify the endianness of the object files. This only affects
2445 disassembly. This can be useful when disassembling a file format which
2446 does not describe endianness information, such as S-records.
2447
2448 @item -f
2449 @itemx --file-headers
2450 @cindex object file header
2451 Display summary information from the overall header of
2452 each of the @var{objfile} files.
2453
2454 @item -F
2455 @itemx --file-offsets
2456 @cindex object file offsets
2457 When disassembling sections, whenever a symbol is displayed, also
2458 display the file offset of the region of data that is about to be
2459 dumped. If zeroes are being skipped, then when disassembly resumes,
2460 tell the user how many zeroes were skipped and the file offset of the
2461 location from where the disassembly resumes. When dumping sections,
2462 display the file offset of the location from where the dump starts.
2463
2464 @item --file-start-context
2465 @cindex source code context
2466 Specify that when displaying interlisted source code/disassembly
2467 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2468 context to the start of the file.
2469
2470 @item -h
2471 @itemx --section-headers
2472 @itemx --headers
2473 @cindex section headers
2474 Display summary information from the section headers of the
2475 object file.
2476
2477 File segments may be relocated to nonstandard addresses, for example by
2478 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2479 @command{ld}. However, some object file formats, such as a.out, do not
2480 store the starting address of the file segments. In those situations,
2481 although @command{ld} relocates the sections correctly, using @samp{objdump
2482 -h} to list the file section headers cannot show the correct addresses.
2483 Instead, it shows the usual addresses, which are implicit for the
2484 target.
2485
2486 Note, in some cases it is possible for a section to have both the
2487 READONLY and the NOREAD attributes set. In such cases the NOREAD
2488 attribute takes precedence, but @command{objdump} will report both
2489 since the exact setting of the flag bits might be important.
2490
2491 @item -H
2492 @itemx --help
2493 Print a summary of the options to @command{objdump} and exit.
2494
2495 @item -i
2496 @itemx --info
2497 @cindex architectures available
2498 @cindex object formats available
2499 Display a list showing all architectures and object formats available
2500 for specification with @option{-b} or @option{-m}.
2501
2502 @item -j @var{name}
2503 @itemx --section=@var{name}
2504 @cindex section information
2505 Display information only for section @var{name}.
2506
2507 @item -L
2508 @itemx --process-links
2509 Display the contents of non-debug sections found in separate debuginfo
2510 files that are linked to the main file. This option automatically
2511 implies the @option{-WK} option, and only sections requested by other
2512 command line options will be displayed.
2513
2514 @item -l
2515 @itemx --line-numbers
2516 @cindex source filenames for object files
2517 Label the display (using debugging information) with the filename and
2518 source line numbers corresponding to the object code or relocs shown.
2519 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2520
2521 @item -m @var{machine}
2522 @itemx --architecture=@var{machine}
2523 @cindex architecture
2524 @cindex disassembly architecture
2525 Specify the architecture to use when disassembling object files. This
2526 can be useful when disassembling object files which do not describe
2527 architecture information, such as S-records. You can list the available
2528 architectures with the @option{-i} option.
2529
2530 For most architectures it is possible to supply an architecture
2531 name and a machine name, separated by a colon. For example
2532 @samp{foo:bar} would refer to the @samp{bar} machine type in the
2533 @samp{foo} architecture. This can be helpful if objdump has been
2534 configured to support multiple architectures.
2535
2536 If the target is an ARM architecture then this switch has an
2537 additional effect. It restricts the disassembly to only those
2538 instructions supported by the architecture specified by @var{machine}.
2539 If it is necessary to use this switch because the input file does not
2540 contain any architecture information, but it is also desired to
2541 disassemble all the instructions use @option{-marm}.
2542
2543 @item -M @var{options}
2544 @itemx --disassembler-options=@var{options}
2545 Pass target specific information to the disassembler. Only supported on
2546 some targets. If it is necessary to specify more than one
2547 disassembler option then multiple @option{-M} options can be used or
2548 can be placed together into a comma separated list.
2549
2550 For ARC, @option{dsp} controls the printing of DSP instructions,
2551 @option{spfp} selects the printing of FPX single precision FP
2552 instructions, @option{dpfp} selects the printing of FPX double
2553 precision FP instructions, @option{quarkse_em} selects the printing of
2554 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2555 of double precision assist instructions, @option{fpus} selects the
2556 printing of FPU single precision FP instructions, while @option{fpud}
2557 selects the printing of FPU double precision FP instructions.
2558 Additionally, one can choose to have all the immediates printed in
2559 hexadecimal using @option{hex}. By default, the short immediates are
2560 printed using the decimal representation, while the long immediate
2561 values are printed as hexadecimal.
2562
2563 @option{cpu=...} allows one to enforce a particular ISA when disassembling
2564 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2565 This might be useful to select ARC EM or HS ISA, because architecture is same
2566 for those and disassembler relies on private ELF header data to decide if code
2567 is for EM or HS. This option might be specified multiple times - only the
2568 latest value will be used. Valid values are same as for the assembler
2569 @option{-mcpu=...} option.
2570
2571 If the target is an ARM architecture then this switch can be used to
2572 select which register name set is used during disassembler. Specifying
2573 @option{-M reg-names-std} (the default) will select the register names as
2574 used in ARM's instruction set documentation, but with register 13 called
2575 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2576 @option{-M reg-names-apcs} will select the name set used by the ARM
2577 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2578 just use @samp{r} followed by the register number.
2579
2580 There are also two variants on the APCS register naming scheme enabled
2581 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2582 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2583 with the normal register names or the special register names).
2584
2585 This option can also be used for ARM architectures to force the
2586 disassembler to interpret all instructions as Thumb instructions by
2587 using the switch @option{--disassembler-options=force-thumb}. This can be
2588 useful when attempting to disassemble thumb code produced by other
2589 compilers.
2590
2591 For AArch64 targets this switch can be used to set whether instructions are
2592 disassembled as the most general instruction using the @option{-M no-aliases}
2593 option or whether instruction notes should be generated as comments in the
2594 disasssembly using @option{-M notes}.
2595
2596 For the x86, some of the options duplicate functions of the @option{-m}
2597 switch, but allow finer grained control.
2598 @table @code
2599 @item x86-64
2600 @itemx i386
2601 @itemx i8086
2602 Select disassembly for the given architecture.
2603
2604 @item intel
2605 @itemx att
2606 Select between intel syntax mode and AT&T syntax mode.
2607
2608 @item amd64
2609 @itemx intel64
2610 Select between AMD64 ISA and Intel64 ISA.
2611
2612 @item intel-mnemonic
2613 @itemx att-mnemonic
2614 Select between intel mnemonic mode and AT&T mnemonic mode.
2615 Note: @code{intel-mnemonic} implies @code{intel} and
2616 @code{att-mnemonic} implies @code{att}.
2617
2618 @item addr64
2619 @itemx addr32
2620 @itemx addr16
2621 @itemx data32
2622 @itemx data16
2623 Specify the default address size and operand size. These five options
2624 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2625 appear later in the option string.
2626
2627 @item suffix
2628 When in AT&T mode and also for a limited set of instructions when in Intel
2629 mode, instructs the disassembler to print a mnemonic suffix even when the
2630 suffix could be inferred by the operands or, for certain instructions, the
2631 execution mode's defaults.
2632 @end table
2633
2634 For PowerPC, the @option{-M} argument @option{raw} selects
2635 disasssembly of hardware insns rather than aliases. For example, you
2636 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2637 rather than @code{li}. All of the @option{-m} arguments for
2638 @command{gas} that select a CPU are supported. These are:
2639 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2640 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2641 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2642 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2643 @option{booke32}, @option{cell}, @option{com}, @option{e200z2}, @option{e200z4},
2644 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2645 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2646 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2647 @option{power8}, @option{power9}, @option{power10}, @option{ppc},
2648 @option{ppc32}, @option{ppc64}, @option{ppc64bridge}, @option{ppcps},
2649 @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2650 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9}, @option{pwr10},
2651 @option{pwrx}, @option{titan}, @option{vle}, and @option{future}.
2652 @option{32} and @option{64} modify the default or a prior CPU
2653 selection, disabling and enabling 64-bit insns respectively. In
2654 addition, @option{altivec}, @option{any}, @option{lsp}, @option{htm},
2655 @option{vsx}, @option{spe} and @option{spe2} add capabilities to a
2656 previous @emph{or later} CPU selection.
2657 @option{any} will disassemble any opcode known to
2658 binutils, but in cases where an opcode has two different meanings or
2659 different arguments, you may not see the disassembly you expect.
2660 If you disassemble without giving a CPU selection, a default will be
2661 chosen from information gleaned by BFD from the object files headers,
2662 but the result again may not be as you expect.
2663
2664 For MIPS, this option controls the printing of instruction mnemonic
2665 names and register names in disassembled instructions. Multiple
2666 selections from the following may be specified as a comma separated
2667 string, and invalid options are ignored:
2668
2669 @table @code
2670 @item no-aliases
2671 Print the 'raw' instruction mnemonic instead of some pseudo
2672 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2673 'sll' instead of 'nop', etc.
2674
2675 @item msa
2676 Disassemble MSA instructions.
2677
2678 @item virt
2679 Disassemble the virtualization ASE instructions.
2680
2681 @item xpa
2682 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2683
2684 @item gpr-names=@var{ABI}
2685 Print GPR (general-purpose register) names as appropriate
2686 for the specified ABI. By default, GPR names are selected according to
2687 the ABI of the binary being disassembled.
2688
2689 @item fpr-names=@var{ABI}
2690 Print FPR (floating-point register) names as
2691 appropriate for the specified ABI. By default, FPR numbers are printed
2692 rather than names.
2693
2694 @item cp0-names=@var{ARCH}
2695 Print CP0 (system control coprocessor; coprocessor 0) register names
2696 as appropriate for the CPU or architecture specified by
2697 @var{ARCH}. By default, CP0 register names are selected according to
2698 the architecture and CPU of the binary being disassembled.
2699
2700 @item hwr-names=@var{ARCH}
2701 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2702 as appropriate for the CPU or architecture specified by
2703 @var{ARCH}. By default, HWR names are selected according to
2704 the architecture and CPU of the binary being disassembled.
2705
2706 @item reg-names=@var{ABI}
2707 Print GPR and FPR names as appropriate for the selected ABI.
2708
2709 @item reg-names=@var{ARCH}
2710 Print CPU-specific register names (CP0 register and HWR names)
2711 as appropriate for the selected CPU or architecture.
2712 @end table
2713
2714 For any of the options listed above, @var{ABI} or
2715 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2716 rather than names, for the selected types of registers.
2717 You can list the available values of @var{ABI} and @var{ARCH} using
2718 the @option{--help} option.
2719
2720 For VAX, you can specify function entry addresses with @option{-M
2721 entry:0xf00ba}. You can use this multiple times to properly
2722 disassemble VAX binary files that don't contain symbol tables (like
2723 ROM dumps). In these cases, the function entry mask would otherwise
2724 be decoded as VAX instructions, which would probably lead the rest
2725 of the function being wrongly disassembled.
2726
2727 @item -p
2728 @itemx --private-headers
2729 Print information that is specific to the object file format. The exact
2730 information printed depends upon the object file format. For some
2731 object file formats, no additional information is printed.
2732
2733 @item -P @var{options}
2734 @itemx --private=@var{options}
2735 Print information that is specific to the object file format. The
2736 argument @var{options} is a comma separated list that depends on the
2737 format (the lists of options is displayed with the help).
2738
2739 For XCOFF, the available options are:
2740 @table @code
2741 @item header
2742 @item aout
2743 @item sections
2744 @item syms
2745 @item relocs
2746 @item lineno,
2747 @item loader
2748 @item except
2749 @item typchk
2750 @item traceback
2751 @item toc
2752 @item ldinfo
2753 @end table
2754
2755 Not all object formats support this option. In particular the ELF
2756 format does not use it.
2757
2758 @item -r
2759 @itemx --reloc
2760 @cindex relocation entries, in object file
2761 Print the relocation entries of the file. If used with @option{-d} or
2762 @option{-D}, the relocations are printed interspersed with the
2763 disassembly.
2764
2765 @item -R
2766 @itemx --dynamic-reloc
2767 @cindex dynamic relocation entries, in object file
2768 Print the dynamic relocation entries of the file. This is only
2769 meaningful for dynamic objects, such as certain types of shared
2770 libraries. As for @option{-r}, if used with @option{-d} or
2771 @option{-D}, the relocations are printed interspersed with the
2772 disassembly.
2773
2774 @item -s
2775 @itemx --full-contents
2776 @cindex sections, full contents
2777 @cindex object file sections
2778 Display the full contents of any sections requested. By default all
2779 non-empty sections are displayed.
2780
2781 @item -S
2782 @itemx --source
2783 @cindex source disassembly
2784 @cindex disassembly, with source
2785 Display source code intermixed with disassembly, if possible. Implies
2786 @option{-d}.
2787
2788 @item --show-all-symbols
2789 When disassembling, show all the symbols that match a given address,
2790 not just the first one.
2791
2792 @item --source-comment[=@var{txt}]
2793 @cindex source disassembly
2794 @cindex disassembly, with source
2795 Like the @option{-S} option, but all source code lines are displayed
2796 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2797 string which can be used to distinguish the assembler code from the
2798 source code. If @var{txt} is not provided then a default string of
2799 @var{``# ``} (hash followed by a space), will be used.
2800
2801 @item --prefix=@var{prefix}
2802 @cindex Add prefix to absolute paths
2803 Specify @var{prefix} to add to the absolute paths when used with
2804 @option{-S}.
2805
2806 @item --prefix-strip=@var{level}
2807 @cindex Strip absolute paths
2808 Indicate how many initial directory names to strip off the hardwired
2809 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2810
2811 @item --show-raw-insn
2812 When disassembling instructions, print the instruction in hex as well as
2813 in symbolic form. This is the default except when
2814 @option{--prefix-addresses} is used.
2815
2816 @item --no-show-raw-insn
2817 When disassembling instructions, do not print the instruction bytes.
2818 This is the default when @option{--prefix-addresses} is used.
2819
2820 @item --insn-width=@var{width}
2821 @cindex Instruction width
2822 Display @var{width} bytes on a single line when disassembling
2823 instructions.
2824
2825 @item --visualize-jumps[=color|=extended-color|=off]
2826 Visualize jumps that stay inside a function by drawing ASCII art between
2827 the start and target addresses. The optional @option{=color} argument
2828 adds color to the output using simple terminal colors. Alternatively
2829 the @option{=extended-color} argument will add color using 8bit
2830 colors, but these might not work on all terminals.
2831
2832 If it is necessary to disable the @option{visualize-jumps} option
2833 after it has previously been enabled then use
2834 @option{visualize-jumps=off}.
2835
2836 @item --disassembler-color=off
2837 @itemx --disassembler-color=terminal
2838 @itemx --disassembler-color=on|color|colour
2839 @itemx --disassembler-color=extened|extended-color|extened-colour
2840 Enables or disables the use of colored syntax highlighting in
2841 disassembly output. The default behaviour is determined via a
2842 configure time option. Note, not all architectures support colored
2843 syntax highlighting, and depending upon the terminal used, colored
2844 output may not actually be legible.
2845
2846 The @option{on} argument adds colors using simple terminal colors.
2847
2848 The @option{terminal} argument does the same, but only if the output
2849 device is a terminal.
2850
2851 The @option{extended-color} argument is similar to the @option{on}
2852 argument, but it uses 8-bit colors. These may not work on all
2853 terminals.
2854
2855 The @option{off} argument disables colored disassembly.
2856
2857 @item -W[lLiaprmfFsoORtUuTgAckK]
2858 @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]
2859 @include debug.options.texi
2860
2861 @item --dwarf-check
2862 Enable additional checks for consistency of Dwarf information.
2863
2864 @include ctf.options.texi
2865
2866 @include sframe.options.texi
2867
2868 @item -G
2869 @itemx --stabs
2870 @cindex stab
2871 @cindex .stab
2872 @cindex debug symbols
2873 @cindex ELF object file format
2874 Display the full contents of any sections requested. Display the
2875 contents of the .stab and .stab.index and .stab.excl sections from an
2876 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2877 @code{.stab} debugging symbol-table entries are carried in an ELF
2878 section. In most other file formats, debugging symbol-table entries are
2879 interleaved with linkage symbols, and are visible in the @option{--syms}
2880 output.
2881
2882 @item --start-address=@var{address}
2883 @cindex start-address
2884 Start displaying data at the specified address. This affects the output
2885 of the @option{-d}, @option{-r} and @option{-s} options.
2886
2887 @item --stop-address=@var{address}
2888 @cindex stop-address
2889 Stop displaying data at the specified address. This affects the output
2890 of the @option{-d}, @option{-r} and @option{-s} options.
2891
2892 @item -t
2893 @itemx --syms
2894 @cindex symbol table entries, printing
2895 Print the symbol table entries of the file.
2896 This is similar to the information provided by the @samp{nm} program,
2897 although the display format is different. The format of the output
2898 depends upon the format of the file being dumped, but there are two main
2899 types. One looks like this:
2900
2901 @smallexample
2902 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2903 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2904 @end smallexample
2905
2906 where the number inside the square brackets is the number of the entry
2907 in the symbol table, the @var{sec} number is the section number, the
2908 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2909 symbol's type, the @var{scl} number is the symbol's storage class and
2910 the @var{nx} value is the number of auxiliary entries associated with
2911 the symbol. The last two fields are the symbol's value and its name.
2912
2913 The other common output format, usually seen with ELF based files,
2914 looks like this:
2915
2916 @smallexample
2917 00000000 l d .bss 00000000 .bss
2918 00000000 g .text 00000000 fred
2919 @end smallexample
2920
2921 Here the first number is the symbol's value (sometimes referred to as
2922 its address). The next field is actually a set of characters and
2923 spaces indicating the flag bits that are set on the symbol. These
2924 characters are described below. Next is the section with which the
2925 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2926 not connected with any section), or @emph{*UND*} if the section is
2927 referenced in the file being dumped, but not defined there.
2928
2929 After the section name comes another field, a number, which for common
2930 symbols is the alignment and for other symbol is the size. Finally
2931 the symbol's name is displayed.
2932
2933 The flag characters are divided into 7 groups as follows:
2934 @table @code
2935 @item l
2936 @itemx g
2937 @itemx u
2938 @itemx !
2939 The symbol is a local (l), global (g), unique global (u), neither
2940 global nor local (a space) or both global and local (!). A
2941 symbol can be neither local or global for a variety of reasons, e.g.,
2942 because it is used for debugging, but it is probably an indication of
2943 a bug if it is ever both local and global. Unique global symbols are
2944 a GNU extension to the standard set of ELF symbol bindings. For such
2945 a symbol the dynamic linker will make sure that in the entire process
2946 there is just one symbol with this name and type in use.
2947
2948 @item w
2949 The symbol is weak (w) or strong (a space).
2950
2951 @item C
2952 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2953
2954 @item W
2955 The symbol is a warning (W) or a normal symbol (a space). A warning
2956 symbol's name is a message to be displayed if the symbol following the
2957 warning symbol is ever referenced.
2958
2959 @item I
2960 @item i
2961 The symbol is an indirect reference to another symbol (I), a function
2962 to be evaluated during reloc processing (i) or a normal symbol (a
2963 space).
2964
2965 @item d
2966 @itemx D
2967 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2968 normal symbol (a space).
2969
2970 @item F
2971 @item f
2972 @item O
2973 The symbol is the name of a function (F) or a file (f) or an object
2974 (O) or just a normal symbol (a space).
2975 @end table
2976
2977 @item -T
2978 @itemx --dynamic-syms
2979 @cindex dynamic symbol table entries, printing
2980 Print the dynamic symbol table entries of the file. This is only
2981 meaningful for dynamic objects, such as certain types of shared
2982 libraries. This is similar to the information provided by the @samp{nm}
2983 program when given the @option{-D} (@option{--dynamic}) option.
2984
2985 The output format is similar to that produced by the @option{--syms}
2986 option, except that an extra field is inserted before the symbol's
2987 name, giving the version information associated with the symbol.
2988 If the version is the default version to be used when resolving
2989 unversioned references to the symbol then it's displayed as is,
2990 otherwise it's put into parentheses.
2991
2992 @item --special-syms
2993 When displaying symbols include those which the target considers to be
2994 special in some way and which would not normally be of interest to the
2995 user.
2996
2997 @item -U @var{[d|i|l|e|x|h]}
2998 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
2999 Controls the display of UTF-8 encoded multibyte characters in strings.
3000 The default (@option{--unicode=default}) is to give them no special
3001 treatment. The @option{--unicode=locale} option displays the sequence
3002 in the current locale, which may or may not support them. The options
3003 @option{--unicode=hex} and @option{--unicode=invalid} display them as
3004 hex byte sequences enclosed by either angle brackets or curly braces.
3005
3006 The @option{--unicode=escape} option displays them as escape sequences
3007 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
3008 them as escape sequences highlighted in red (if supported by the
3009 output device). The colouring is intended to draw attention to the
3010 presence of unicode sequences where they might not be expected.
3011
3012 @item -V
3013 @itemx --version
3014 Print the version number of @command{objdump} and exit.
3015
3016 @item -x
3017 @itemx --all-headers
3018 @cindex all header information, object file
3019 @cindex header information, all
3020 Display all available header information, including the symbol table and
3021 relocation entries. Using @option{-x} is equivalent to specifying all of
3022 @option{-a -f -h -p -r -t}.
3023
3024 @item -w
3025 @itemx --wide
3026 @cindex wide output, printing
3027 Format some lines for output devices that have more than 80 columns.
3028 Also do not truncate symbol names when they are displayed.
3029
3030 @item -z
3031 @itemx --disassemble-zeroes
3032 Normally the disassembly output will skip blocks of zeroes. This
3033 option directs the disassembler to disassemble those blocks, just like
3034 any other data.
3035 @end table
3036
3037 @c man end
3038
3039 @ignore
3040 @c man begin SEEALSO objdump
3041 nm(1), readelf(1), and the Info entries for @file{binutils}.
3042 @c man end
3043 @end ignore
3044
3045 @node ranlib
3046 @chapter ranlib
3047
3048 @kindex ranlib
3049 @cindex archive contents
3050 @cindex symbol index
3051
3052 @c man title ranlib generate an index to an archive
3053
3054 @smallexample
3055 @c man begin SYNOPSIS ranlib
3056 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
3057 @c man end
3058 @end smallexample
3059
3060 @c man begin DESCRIPTION ranlib
3061
3062 @command{ranlib} generates an index to the contents of an archive and
3063 stores it in the archive. The index lists each symbol defined by a
3064 member of an archive that is a relocatable object file.
3065
3066 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
3067
3068 An archive with such an index speeds up linking to the library and
3069 allows routines in the library to call each other without regard to
3070 their placement in the archive.
3071
3072 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
3073 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
3074 @xref{ar}.
3075
3076 @c man end
3077
3078 @c man begin OPTIONS ranlib
3079
3080 @table @env
3081 @item -h
3082 @itemx -H
3083 @itemx --help
3084 Show usage information for @command{ranlib}.
3085
3086 @item -v
3087 @itemx -V
3088 @itemx --version
3089 Show the version number of @command{ranlib}.
3090
3091 @item -D
3092 @cindex deterministic archives
3093 @kindex --enable-deterministic-archives
3094 Operate in @emph{deterministic} mode. The symbol map archive member's
3095 header will show zero for the UID, GID, and timestamp. When this
3096 option is used, multiple runs will produce identical output files.
3097
3098 If @file{binutils} was configured with
3099 @option{--enable-deterministic-archives}, then this mode is on by
3100 default. It can be disabled with the @samp{-U} option, described
3101 below.
3102
3103 @item -t
3104 Update the timestamp of the symbol map of an archive.
3105
3106 @item -U
3107 @cindex deterministic archives
3108 @kindex --enable-deterministic-archives
3109 Do @emph{not} operate in @emph{deterministic} mode. This is the
3110 inverse of the @samp{-D} option, above: the archive index will get
3111 actual UID, GID, timestamp, and file mode values.
3112
3113 If @file{binutils} was configured @emph{without}
3114 @option{--enable-deterministic-archives}, then this mode is on by
3115 default.
3116
3117 @end table
3118
3119 @c man end
3120
3121 @ignore
3122 @c man begin SEEALSO ranlib
3123 ar(1), nm(1), and the Info entries for @file{binutils}.
3124 @c man end
3125 @end ignore
3126
3127 @node size
3128 @chapter size
3129
3130 @kindex size
3131 @cindex section sizes
3132
3133 @c man title size list section sizes and total size of binary files
3134
3135 @smallexample
3136 @c man begin SYNOPSIS size
3137 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
3138 [@option{--help}]
3139 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
3140 [@option{--common}]
3141 [@option{-t}|@option{--totals}]
3142 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
3143 [@option{-f}]
3144 [@var{objfile}@dots{}]
3145 @c man end
3146 @end smallexample
3147
3148 @c man begin DESCRIPTION size
3149
3150 The @sc{gnu} @command{size} utility lists the section sizes and the total
3151 size for each of the binary files @var{objfile} on its argument list.
3152 By default, one line of output is generated for each file or each
3153 module if the file is an archive.
3154
3155 @var{objfile}@dots{} are the files to be examined. If none are
3156 specified, the file @code{a.out} will be used instead.
3157
3158 @c man end
3159
3160 @c man begin OPTIONS size
3161
3162 The command-line options have the following meanings:
3163
3164 @table @env
3165 @item -A
3166 @itemx -B
3167 @itemx -G
3168 @itemx --format=@var{compatibility}
3169 @cindex @command{size} display format
3170 Using one of these options, you can choose whether the output from @sc{gnu}
3171 @command{size} resembles output from System V @command{size} (using @option{-A},
3172 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3173 @option{--format=berkeley}). The default is the one-line format similar to
3174 Berkeley's. Alternatively, you can choose the GNU format output
3175 (using @option{-G}, or @option{--format=gnu}), this is similar to
3176 Berkeley's output format, but sizes are counted differently.
3177 @c Bonus for doc-source readers: you can also say --format=strange (or
3178 @c anything else that starts with 's') for sysv, and --format=boring (or
3179 @c anything else that starts with 'b') for Berkeley.
3180
3181 Here is an example of the Berkeley (default) format of output from
3182 @command{size}:
3183 @smallexample
3184 $ size --format=Berkeley ranlib size
3185 text data bss dec hex filename
3186 294880 81920 11592 388392 5ed28 ranlib
3187 294880 81920 11888 388688 5ee50 size
3188 @end smallexample
3189
3190 The Berkeley style output counts read only data in the @code{text}
3191 column, not in the @code{data} column, the @code{dec} and @code{hex}
3192 columns both display the sum of the @code{text}, @code{data}, and
3193 @code{bss} columns in decimal and hexadecimal respectively.
3194
3195 The GNU format counts read only data in the @code{data} column, not
3196 the @code{text} column, and only displays the sum of the @code{text},
3197 @code{data}, and @code{bss} columns once, in the @code{total} column.
3198 The @option{--radix} option can be used to change the number base for
3199 all columns. Here is the same data displayed with GNU conventions:
3200
3201 @smallexample
3202 $ size --format=GNU ranlib size
3203 text data bss total filename
3204 279880 96920 11592 388392 ranlib
3205 279880 96920 11888 388688 size
3206 @end smallexample
3207
3208 @noindent
3209 This is the same data, but displayed closer to System V conventions:
3210
3211 @smallexample
3212 $ size --format=SysV ranlib size
3213 ranlib :
3214 section size addr
3215 .text 294880 8192
3216 .data 81920 303104
3217 .bss 11592 385024
3218 Total 388392
3219
3220
3221 size :
3222 section size addr
3223 .text 294880 8192
3224 .data 81920 303104
3225 .bss 11888 385024
3226 Total 388688
3227 @end smallexample
3228
3229 @item --help
3230 @itemx -h
3231 @itemx -H
3232 @item -?
3233 Show a summary of acceptable arguments and options.
3234
3235 @item -d
3236 @itemx -o
3237 @itemx -x
3238 @itemx --radix=@var{number}
3239 @cindex @command{size} number format
3240 @cindex radix for section sizes
3241 Using one of these options, you can control whether the size of each
3242 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3243 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3244 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3245 values (8, 10, 16) are supported. The total size is always given in two
3246 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3247 octal and hexadecimal if you're using @option{-o}.
3248
3249 @item --common
3250 Print total size of common symbols in each file. When using Berkeley
3251 or GNU format these are included in the bss size.
3252
3253 @item -t
3254 @itemx --totals
3255 Show totals of all objects listed (Berkeley or GNU format mode only).
3256
3257 @item --target=@var{bfdname}
3258 @cindex object code format
3259 Specify that the object-code format for @var{objfile} is
3260 @var{bfdname}. This option may not be necessary; @command{size} can
3261 automatically recognize many formats.
3262 @xref{Target Selection}, for more information.
3263
3264 @item -v
3265 @item -V
3266 @itemx --version
3267 Display the version number of @command{size}.
3268
3269 @item -f
3270 Ignored. This option is used by other versions of the @command{size}
3271 program, but it is not supported by the GNU Binutils version.
3272
3273 @end table
3274
3275 @c man end
3276
3277 @ignore
3278 @c man begin SEEALSO size
3279 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3280 @c man end
3281 @end ignore
3282
3283 @node strings
3284 @chapter strings
3285 @kindex strings
3286 @cindex listings strings
3287 @cindex printing strings
3288 @cindex strings, printing
3289
3290 @c man title strings print the sequences of printable characters in files
3291
3292 @smallexample
3293 @c man begin SYNOPSIS strings
3294 strings [@option{-afovV}] [@option{-}@var{min-len}]
3295 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3296 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3297 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3298 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
3299 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3300 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3301 [@option{-w}] [@option{--include-all-whitespace}]
3302 [@option{-s}] [@option{--output-separator} @var{sep_string}]
3303 [@option{--help}] [@option{--version}] @var{file}@dots{}
3304 @c man end
3305 @end smallexample
3306
3307 @c man begin DESCRIPTION strings
3308
3309 For each @var{file} given, @sc{gnu} @command{strings} prints the
3310 printable character sequences that are at least 4 characters long (or
3311 the number given with the options below) and are followed by an
3312 unprintable character.
3313
3314 Depending upon how the strings program was configured it will default
3315 to either displaying all the printable sequences that it can find in
3316 each file, or only those sequences that are in loadable, initialized
3317 data sections. If the file type is unrecognizable, or if strings is
3318 reading from stdin then it will always display all of the printable
3319 sequences that it can find.
3320
3321 For backwards compatibility any file that occurs after a command-line
3322 option of just @option{-} will also be scanned in full, regardless of
3323 the presence of any @option{-d} option.
3324
3325 @command{strings} is mainly useful for determining the contents of
3326 non-text files.
3327
3328 @c man end
3329
3330 @c man begin OPTIONS strings
3331
3332 @table @env
3333 @item -a
3334 @itemx --all
3335 @itemx -
3336 Scan the whole file, regardless of what sections it contains or
3337 whether those sections are loaded or initialized. Normally this is
3338 the default behaviour, but strings can be configured so that the
3339 @option{-d} is the default instead.
3340
3341 The @option{-} option is position dependent and forces strings to
3342 perform full scans of any file that is mentioned after the @option{-}
3343 on the command line, even if the @option{-d} option has been
3344 specified.
3345
3346 @item -d
3347 @itemx --data
3348 Only print strings from initialized, loaded data sections in the
3349 file. This may reduce the amount of garbage in the output, but it
3350 also exposes the strings program to any security flaws that may be
3351 present in the BFD library used to scan and load sections. Strings
3352 can be configured so that this option is the default behaviour. In
3353 such cases the @option{-a} option can be used to avoid using the BFD
3354 library and instead just print all of the strings found in the file.
3355
3356 @item -f
3357 @itemx --print-file-name
3358 Print the name of the file before each string.
3359
3360 @item --help
3361 Print a summary of the program usage on the standard output and exit.
3362
3363 @item -@var{min-len}
3364 @itemx -n @var{min-len}
3365 @itemx --bytes=@var{min-len}
3366 Print sequences of displayable characters that are at least
3367 @var{min-len} characters long. If not specified a default minimum
3368 length of 4 is used. The distinction between displayable and
3369 non-displayable characters depends upon the setting of the
3370 @option{-e} and @option{-U} options. Sequences are always terminated
3371 at control characters such as new-line and carriage-return, but not
3372 the tab character.
3373
3374 @item -o
3375 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3376 act like @samp{-t d} instead. Since we can not be compatible with both
3377 ways, we simply chose one.
3378
3379 @item -t @var{radix}
3380 @itemx --radix=@var{radix}
3381 Print the offset within the file before each string. The single
3382 character argument specifies the radix of the offset---@samp{o} for
3383 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3384
3385 @item -e @var{encoding}
3386 @itemx --encoding=@var{encoding}
3387 Select the character encoding of the strings that are to be found.
3388 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3389 characters (default), @samp{S} =
3390 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3391 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3392 littleendian. Useful for finding wide character strings. (@samp{l}
3393 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3394
3395 @item -U @var{[d|i|l|e|x|h]}
3396 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3397 Controls the display of UTF-8 encoded multibyte characters in strings.
3398 The default (@option{--unicode=default}) is to give them no special
3399 treatment, and instead rely upon the setting of the
3400 @option{--encoding} option. The other values for this option
3401 automatically enable @option{--encoding=S}.
3402
3403 The @option{--unicode=invalid} option treats them as non-graphic
3404 characters and hence not part of a valid string. All the remaining
3405 options treat them as valid string characters.
3406
3407 The @option{--unicode=locale} option displays them in the current
3408 locale, which may or may not support UTF-8 encoding. The
3409 @option{--unicode=hex} option displays them as hex byte sequences
3410 enclosed between @var{<>} characters. The @option{--unicode=escape}
3411 option displays them as escape sequences (@var{\uxxxx}) and the
3412 @option{--unicode=highlight} option displays them as escape sequences
3413 highlighted in red (if supported by the output device). The colouring
3414 is intended to draw attention to the presence of unicode sequences
3415 where they might not be expected.
3416
3417 @item -T @var{bfdname}
3418 @itemx --target=@var{bfdname}
3419 @cindex object code format
3420 Specify an object code format other than your system's default format.
3421 @xref{Target Selection}, for more information.
3422
3423 @item -v
3424 @itemx -V
3425 @itemx --version
3426 Print the program version number on the standard output and exit.
3427
3428 @item -w
3429 @itemx --include-all-whitespace
3430 By default tab and space characters are included in the strings that
3431 are displayed, but other whitespace characters, such a newlines and
3432 carriage returns, are not. The @option{-w} option changes this so
3433 that all whitespace characters are considered to be part of a string.
3434
3435 @item -s
3436 @itemx --output-separator
3437 By default, output strings are delimited by a new-line. This option
3438 allows you to supply any string to be used as the output record
3439 separator. Useful with --include-all-whitespace where strings
3440 may contain new-lines internally.
3441 @end table
3442
3443 @c man end
3444
3445 @ignore
3446 @c man begin SEEALSO strings
3447 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3448 and the Info entries for @file{binutils}.
3449 @c man end
3450 @end ignore
3451
3452 @node strip
3453 @chapter strip
3454
3455 @kindex strip
3456 @cindex removing symbols
3457 @cindex discarding symbols
3458 @cindex symbols, discarding
3459
3460 @c man title strip discard symbols and other data from object files
3461
3462 @smallexample
3463 @c man begin SYNOPSIS strip
3464 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3465 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3466 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3467 [@option{-s}|@option{--strip-all}]
3468 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3469 [@option{--strip-dwo}]
3470 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3471 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3472 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3473 [@option{-w}|@option{--wildcard}]
3474 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3475 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3476 [@option{--keep-section=}@var{sectionpattern}]
3477 [@option{--remove-relocations=}@var{sectionpattern}]
3478 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3479 [@option{-D}|@option{--enable-deterministic-archives}]
3480 [@option{-U}|@option{--disable-deterministic-archives}]
3481 [@option{--keep-section-symbols}]
3482 [@option{--keep-file-symbols}]
3483 [@option{--only-keep-debug}]
3484 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3485 [@option{--help}] [@option{--info}]
3486 @var{objfile}@dots{}
3487 @c man end
3488 @end smallexample
3489
3490 @c man begin DESCRIPTION strip
3491
3492 @sc{gnu} @command{strip} discards all symbols from object files
3493 @var{objfile}. The list of object files may include archives.
3494 At least one object file must be given.
3495
3496 @command{strip} modifies the files named in its argument,
3497 rather than writing modified copies under different names.
3498
3499 @c man end
3500
3501 @c man begin OPTIONS strip
3502
3503 @table @env
3504 @item -F @var{bfdname}
3505 @itemx --target=@var{bfdname}
3506 Treat the original @var{objfile} as a file with the object
3507 code format @var{bfdname}, and rewrite it in the same format.
3508 @xref{Target Selection}, for more information.
3509
3510 @item --help
3511 Show a summary of the options to @command{strip} and exit.
3512
3513 @item --info
3514 Display a list showing all architectures and object formats available.
3515
3516 @item -I @var{bfdname}
3517 @itemx --input-target=@var{bfdname}
3518 Treat the original @var{objfile} as a file with the object
3519 code format @var{bfdname}.
3520 @xref{Target Selection}, for more information.
3521
3522 @item -O @var{bfdname}
3523 @itemx --output-target=@var{bfdname}
3524 Replace @var{objfile} with a file in the output format @var{bfdname}.
3525 @xref{Target Selection}, for more information.
3526
3527 @item -R @var{sectionname}
3528 @itemx --remove-section=@var{sectionname}
3529 Remove any section named @var{sectionname} from the output file, in
3530 addition to whatever sections would otherwise be removed. This
3531 option may be given more than once. Note that using this option
3532 inappropriately may make the output file unusable. The wildcard
3533 character @samp{*} may be given at the end of @var{sectionname}. If
3534 so, then any section starting with @var{sectionname} will be removed.
3535
3536 If the first character of @var{sectionpattern} is the exclamation
3537 point (!) then matching sections will not be removed even if an
3538 earlier use of @option{--remove-section} on the same command line
3539 would otherwise remove it. For example:
3540
3541 @smallexample
3542 --remove-section=.text.* --remove-section=!.text.foo
3543 @end smallexample
3544
3545 will remove all sections matching the pattern '.text.*', but will not
3546 remove the section '.text.foo'.
3547
3548 @item --keep-section=@var{sectionpattern}
3549 When removing sections from the output file, keep sections that match
3550 @var{sectionpattern}.
3551
3552 @item --remove-relocations=@var{sectionpattern}
3553 Remove relocations from the output file for any section matching
3554 @var{sectionpattern}. This option may be given more than once. Note
3555 that using this option inappropriately may make the output file
3556 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3557 For example:
3558
3559 @smallexample
3560 --remove-relocations=.text.*
3561 @end smallexample
3562
3563 will remove the relocations for all sections matching the patter
3564 '.text.*'.
3565
3566 If the first character of @var{sectionpattern} is the exclamation
3567 point (!) then matching sections will not have their relocation
3568 removed even if an earlier use of @option{--remove-relocations} on the
3569 same command line would otherwise cause the relocations to be removed.
3570 For example:
3571
3572 @smallexample
3573 --remove-relocations=.text.* --remove-relocations=!.text.foo
3574 @end smallexample
3575
3576 will remove all relocations for sections matching the pattern
3577 '.text.*', but will not remove relocations for the section
3578 '.text.foo'.
3579
3580 @item -s
3581 @itemx --strip-all
3582 Remove all symbols.
3583
3584 @item -g
3585 @itemx -S
3586 @itemx -d
3587 @itemx --strip-debug
3588 Remove debugging symbols only.
3589
3590 @item --strip-dwo
3591 Remove the contents of all DWARF .dwo sections, leaving the
3592 remaining debugging sections and all symbols intact.
3593 See the description of this option in the @command{objcopy} section
3594 for more information.
3595
3596 @item --strip-unneeded
3597 Remove all symbols that are not needed for relocation processing in
3598 addition to debugging symbols and sections stripped by
3599 @option{--strip-debug}.
3600
3601 @item -K @var{symbolname}
3602 @itemx --keep-symbol=@var{symbolname}
3603 When stripping symbols, keep symbol @var{symbolname} even if it would
3604 normally be stripped. This option may be given more than once.
3605
3606 @item -M
3607 @itemx --merge-notes
3608 @itemx --no-merge-notes
3609 For ELF files, attempt (or do not attempt) to reduce the size of any
3610 SHT_NOTE type sections by removing duplicate notes. The default is to
3611 attempt this reduction unless stripping debug or DWO information.
3612
3613 @item -N @var{symbolname}
3614 @itemx --strip-symbol=@var{symbolname}
3615 Remove symbol @var{symbolname} from the source file. This option may be
3616 given more than once, and may be combined with strip options other than
3617 @option{-K}.
3618
3619 @item -o @var{file}
3620 Put the stripped output in @var{file}, rather than replacing the
3621 existing file. When this argument is used, only one @var{objfile}
3622 argument may be specified.
3623
3624 @item -p
3625 @itemx --preserve-dates
3626 Preserve the access and modification dates of the file.
3627
3628 @item -D
3629 @itemx --enable-deterministic-archives
3630 @cindex deterministic archives
3631 @kindex --enable-deterministic-archives
3632 Operate in @emph{deterministic} mode. When copying archive members
3633 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3634 and use consistent file modes for all files.
3635
3636 If @file{binutils} was configured with
3637 @option{--enable-deterministic-archives}, then this mode is on by default.
3638 It can be disabled with the @samp{-U} option, below.
3639
3640 @item -U
3641 @itemx --disable-deterministic-archives
3642 @cindex deterministic archives
3643 @kindex --enable-deterministic-archives
3644 Do @emph{not} operate in @emph{deterministic} mode. This is the
3645 inverse of the @option{-D} option, above: when copying archive members
3646 and writing the archive index, use their actual UID, GID, timestamp,
3647 and file mode values.
3648
3649 This is the default unless @file{binutils} was configured with
3650 @option{--enable-deterministic-archives}.
3651
3652 @item -w
3653 @itemx --wildcard
3654 Permit regular expressions in @var{symbolname}s used in other command
3655 line options. The question mark (?), asterisk (*), backslash (\) and
3656 square brackets ([]) operators can be used anywhere in the symbol
3657 name. If the first character of the symbol name is the exclamation
3658 point (!) then the sense of the switch is reversed for that symbol.
3659 For example:
3660
3661 @smallexample
3662 -w -K !foo -K fo*
3663 @end smallexample
3664
3665 would cause strip to only keep symbols that start with the letters
3666 ``fo'', but to discard the symbol ``foo''.
3667
3668 @item -x
3669 @itemx --discard-all
3670 Remove non-global symbols.
3671
3672 @item -X
3673 @itemx --discard-locals
3674 Remove compiler-generated local symbols.
3675 (These usually start with @samp{L} or @samp{.}.)
3676
3677 @item --keep-section-symbols
3678 When stripping a file, perhaps with @option{--strip-debug} or
3679 @option{--strip-unneeded}, retain any symbols specifying section names,
3680 which would otherwise get stripped.
3681
3682 @item --keep-file-symbols
3683 When stripping a file, perhaps with @option{--strip-debug} or
3684 @option{--strip-unneeded}, retain any symbols specifying source file names,
3685 which would otherwise get stripped.
3686
3687 @item --only-keep-debug
3688 Strip a file, emptying the contents of any sections that would not be
3689 stripped by @option{--strip-debug} and leaving the debugging sections
3690 intact. In ELF files, this preserves all the note sections in the
3691 output as well.
3692
3693 Note - the section headers of the stripped sections are preserved,
3694 including their sizes, but the contents of the section are discarded.
3695 The section headers are preserved so that other tools can match up the
3696 debuginfo file with the real executable, even if that executable has
3697 been relocated to a different address space.
3698
3699 The intention is that this option will be used in conjunction with
3700 @option{--add-gnu-debuglink} to create a two part executable. One a
3701 stripped binary which will occupy less space in RAM and in a
3702 distribution and the second a debugging information file which is only
3703 needed if debugging abilities are required. The suggested procedure
3704 to create these files is as follows:
3705
3706 @enumerate
3707 @item Link the executable as normal. Assuming that it is called
3708 @code{foo} then...
3709 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3710 create a file containing the debugging info.
3711 @item Run @code{objcopy --strip-debug foo} to create a
3712 stripped executable.
3713 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3714 to add a link to the debugging info into the stripped executable.
3715 @end enumerate
3716
3717 Note---the choice of @code{.dbg} as an extension for the debug info
3718 file is arbitrary. Also the @code{--only-keep-debug} step is
3719 optional. You could instead do this:
3720
3721 @enumerate
3722 @item Link the executable as normal.
3723 @item Copy @code{foo} to @code{foo.full}
3724 @item Run @code{strip --strip-debug foo}
3725 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3726 @end enumerate
3727
3728 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3729 full executable. It does not have to be a file created by the
3730 @option{--only-keep-debug} switch.
3731
3732 Note---this switch is only intended for use on fully linked files. It
3733 does not make sense to use it on object files where the debugging
3734 information may be incomplete. Besides the gnu_debuglink feature
3735 currently only supports the presence of one filename containing
3736 debugging information, not multiple filenames on a one-per-object-file
3737 basis.
3738
3739 @item -V
3740 @itemx --version
3741 Show the version number for @command{strip}.
3742
3743 @item -v
3744 @itemx --verbose
3745 Verbose output: list all object files modified. In the case of
3746 archives, @samp{strip -v} lists all members of the archive.
3747 @end table
3748
3749 @c man end
3750
3751 @ignore
3752 @c man begin SEEALSO strip
3753 the Info entries for @file{binutils}.
3754 @c man end
3755 @end ignore
3756
3757 @node c++filt, addr2line, strip, Top
3758 @chapter c++filt
3759
3760 @kindex c++filt
3761 @cindex demangling C++ symbols
3762
3763 @c man title cxxfilt demangle C++ and Java symbols
3764
3765 @smallexample
3766 @c man begin SYNOPSIS cxxfilt
3767 c++filt [@option{-_}|@option{--strip-underscore}]
3768 [@option{-n}|@option{--no-strip-underscore}]
3769 [@option{-p}|@option{--no-params}]
3770 [@option{-t}|@option{--types}]
3771 [@option{-i}|@option{--no-verbose}]
3772 [@option{-r}|@option{--no-recurse-limit}]
3773 [@option{-R}|@option{--recurse-limit}]
3774 [@option{-s} @var{format}|@option{--format=}@var{format}]
3775 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3776 @c man end
3777 @end smallexample
3778
3779 @c man begin DESCRIPTION cxxfilt
3780
3781 @kindex cxxfilt
3782 The C++ and Java languages provide function overloading, which means
3783 that you can write many functions with the same name, providing that
3784 each function takes parameters of different types. In order to be
3785 able to distinguish these similarly named functions C++ and Java
3786 encode them into a low-level assembler name which uniquely identifies
3787 each different version. This process is known as @dfn{mangling}. The
3788 @command{c++filt}
3789 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3790 MS-DOS this program is named @command{CXXFILT}.}
3791 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3792 names into user-level names so that they can be read.
3793
3794 Every alphanumeric word (consisting of letters, digits, underscores,
3795 dollars, or periods) seen in the input is a potential mangled name.
3796 If the name decodes into a C++ name, the C++ name replaces the
3797 low-level name in the output, otherwise the original word is output.
3798 In this way you can pass an entire assembler source file, containing
3799 mangled names, through @command{c++filt} and see the same source file
3800 containing demangled names.
3801
3802 You can also use @command{c++filt} to decipher individual symbols by
3803 passing them on the command line:
3804
3805 @example
3806 c++filt @var{symbol}
3807 @end example
3808
3809 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3810 names from the standard input instead. All the results are printed on
3811 the standard output. The difference between reading names from the
3812 command line versus reading names from the standard input is that
3813 command-line arguments are expected to be just mangled names and no
3814 checking is performed to separate them from surrounding text. Thus
3815 for example:
3816
3817 @smallexample
3818 c++filt -n _Z1fv
3819 @end smallexample
3820
3821 will work and demangle the name to ``f()'' whereas:
3822
3823 @smallexample
3824 c++filt -n _Z1fv,
3825 @end smallexample
3826
3827 will not work. (Note the extra comma at the end of the mangled
3828 name which makes it invalid). This command however will work:
3829
3830 @smallexample
3831 echo _Z1fv, | c++filt -n
3832 @end smallexample
3833
3834 and will display ``f(),'', i.e., the demangled name followed by a
3835 trailing comma. This behaviour is because when the names are read
3836 from the standard input it is expected that they might be part of an
3837 assembler source file where there might be extra, extraneous
3838 characters trailing after a mangled name. For example:
3839
3840 @smallexample
3841 .type _Z1fv, @@function
3842 @end smallexample
3843
3844 @c man end
3845
3846 @c man begin OPTIONS cxxfilt
3847
3848 @table @env
3849 @item -_
3850 @itemx --strip-underscore
3851 On some systems, both the C and C++ compilers put an underscore in front
3852 of every name. For example, the C name @code{foo} gets the low-level
3853 name @code{_foo}. This option removes the initial underscore. Whether
3854 @command{c++filt} removes the underscore by default is target dependent.
3855
3856 @item -n
3857 @itemx --no-strip-underscore
3858 Do not remove the initial underscore.
3859
3860 @item -p
3861 @itemx --no-params
3862 When demangling the name of a function, do not display the types of
3863 the function's parameters.
3864
3865 @item -t
3866 @itemx --types
3867 Attempt to demangle types as well as function names. This is disabled
3868 by default since mangled types are normally only used internally in
3869 the compiler, and they can be confused with non-mangled names. For example,
3870 a function called ``a'' treated as a mangled type name would be
3871 demangled to ``signed char''.
3872
3873 @item -i
3874 @itemx --no-verbose
3875 Do not include implementation details (if any) in the demangled
3876 output.
3877
3878 @item -r
3879 @itemx -R
3880 @itemx --recurse-limit
3881 @itemx --no-recurse-limit
3882 @itemx --recursion-limit
3883 @itemx --no-recursion-limit
3884 Enables or disables a limit on the amount of recursion performed
3885 whilst demangling strings. Since the name mangling formats allow for
3886 an infinite level of recursion it is possible to create strings whose
3887 decoding will exhaust the amount of stack space available on the host
3888 machine, triggering a memory fault. The limit tries to prevent this
3889 from happening by restricting recursion to 2048 levels of nesting.
3890
3891 The default is for this limit to be enabled, but disabling it may be
3892 necessary in order to demangle truly complicated names. Note however
3893 that if the recursion limit is disabled then stack exhaustion is
3894 possible and any bug reports about such an event will be rejected.
3895
3896 The @option{-r} option is a synonym for the
3897 @option{--no-recurse-limit} option. The @option{-R} option is a
3898 synonym for the @option{--recurse-limit} option.
3899
3900 @item -s @var{format}
3901 @itemx --format=@var{format}
3902 @command{c++filt} can decode various methods of mangling, used by
3903 different compilers. The argument to this option selects which
3904 method it uses:
3905
3906 @table @code
3907 @item auto
3908 Automatic selection based on executable (the default method)
3909 @item gnu
3910 the one used by the @sc{gnu} C++ compiler (g++)
3911 @item lucid
3912 the one used by the Lucid compiler (lcc)
3913 @item arm
3914 the one specified by the C++ Annotated Reference Manual
3915 @item hp
3916 the one used by the HP compiler (aCC)
3917 @item edg
3918 the one used by the EDG compiler
3919 @item gnu-v3
3920 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3921 @item java
3922 the one used by the @sc{gnu} Java compiler (gcj)
3923 @item gnat
3924 the one used by the @sc{gnu} Ada compiler (GNAT).
3925 @end table
3926
3927 @item --help
3928 Print a summary of the options to @command{c++filt} and exit.
3929
3930 @item --version
3931 Print the version number of @command{c++filt} and exit.
3932 @end table
3933
3934 @c man end
3935
3936 @ignore
3937 @c man begin SEEALSO cxxfilt
3938 the Info entries for @file{binutils}.
3939 @c man end
3940 @end ignore
3941
3942 @quotation
3943 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3944 user interface are subject to change in future releases. In particular,
3945 a command-line option may be required in the future to decode a name
3946 passed as an argument on the command line; in other words,
3947
3948 @example
3949 c++filt @var{symbol}
3950 @end example
3951
3952 @noindent
3953 may in a future release become
3954
3955 @example
3956 c++filt @var{option} @var{symbol}
3957 @end example
3958 @end quotation
3959
3960 @node addr2line
3961 @chapter addr2line
3962
3963 @kindex addr2line
3964 @cindex address to file name and line number
3965
3966 @c man title addr2line convert addresses or symbol+offset into file names and line numbers
3967
3968 @smallexample
3969 @c man begin SYNOPSIS addr2line
3970 addr2line [@option{-a}|@option{--addresses}]
3971 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3972 [@option{-C}|@option{--demangle}[=@var{style}]]
3973 [@option{-r}|@option{--no-recurse-limit}]
3974 [@option{-R}|@option{--recurse-limit}]
3975 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3976 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3977 [@option{-i}|@option{--inlines}]
3978 [@option{-p}|@option{--pretty-print}]
3979 [@option{-j}|@option{--section=}@var{name}]
3980 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3981 [addr addr @dots{}]
3982 @c man end
3983 @end smallexample
3984
3985 @c man begin DESCRIPTION addr2line
3986
3987 @command{addr2line} translates addresses or symbol+offset into file names and line numbers.
3988 Given an address or symbol+offset in an executable or an offset in a section of a relocatable
3989 object, it uses the debugging information to figure out which file name and
3990 line number are associated with it.
3991
3992 The executable or relocatable object to use is specified with the @option{-e}
3993 option. The default is the file @file{a.out}. The section in the relocatable
3994 object to use is specified with the @option{-j} option.
3995
3996 @command{addr2line} has two modes of operation.
3997
3998 In the first, hexadecimal addresses or symbol+offset are specified on the command line,
3999 and @command{addr2line} displays the file name and line number for each
4000 address.
4001
4002 In the second, @command{addr2line} reads hexadecimal addresses or symbol+offset from
4003 standard input, and prints the file name and line number for each
4004 address on standard output. In this mode, @command{addr2line} may be used
4005 in a pipe to convert dynamically chosen addresses.
4006
4007 The format of the output is @samp{FILENAME:LINENO}. By default
4008 each input address generates one line of output.
4009
4010 Two options can generate additional lines before each
4011 @samp{FILENAME:LINENO} line (in that order).
4012
4013 If the @option{-a} option is used then a line with the input address
4014 is displayed.
4015
4016 If the @option{-f} option is used, then a line with the
4017 @samp{FUNCTIONNAME} is displayed. This is the name of the function
4018 containing the address.
4019
4020 One option can generate additional lines after the
4021 @samp{FILENAME:LINENO} line.
4022
4023 If the @option{-i} option is used and the code at the given address is
4024 present there because of inlining by the compiler then additional
4025 lines are displayed afterwards. One or two extra lines (if the
4026 @option{-f} option is used) are displayed for each inlined function.
4027
4028 Alternatively if the @option{-p} option is used then each input
4029 address generates a single, long, output line containing the address,
4030 the function name, the file name and the line number. If the
4031 @option{-i} option has also been used then any inlined functions will
4032 be displayed in the same manner, but on separate lines, and prefixed
4033 by the text @samp{(inlined by)}.
4034
4035 If the file name or function name can not be determined,
4036 @command{addr2line} will print two question marks in their place. If the
4037 line number can not be determined, @command{addr2line} will print 0.
4038
4039 When symbol+offset is used, +offset is optional, except when the symbol
4040 is ambigious with a hex number. The resolved symbols can be mangled
4041 or unmangled, except unmangled symbols with + are not allowed.
4042
4043 @c man end
4044
4045 @c man begin OPTIONS addr2line
4046
4047 The long and short forms of options, shown here as alternatives, are
4048 equivalent.
4049
4050 @table @env
4051 @item -a
4052 @itemx --addresses
4053 Display the address before the function name, file and line number
4054 information. The address is printed with a @samp{0x} prefix to easily
4055 identify it.
4056
4057 @item -b @var{bfdname}
4058 @itemx --target=@var{bfdname}
4059 @cindex object code format
4060 Specify that the object-code format for the object files is
4061 @var{bfdname}.
4062
4063 @item -C
4064 @itemx --demangle[=@var{style}]
4065 @cindex demangling in objdump
4066 Decode (@dfn{demangle}) low-level symbol names into user-level names.
4067 Besides removing any initial underscore prepended by the system, this
4068 makes C++ function names readable. Different compilers have different
4069 mangling styles. The optional demangling style argument can be used to
4070 choose an appropriate demangling style for your compiler. @xref{c++filt},
4071 for more information on demangling.
4072
4073 @item -e @var{filename}
4074 @itemx --exe=@var{filename}
4075 Specify the name of the executable for which addresses should be
4076 translated. The default file is @file{a.out}.
4077
4078 @item -f
4079 @itemx --functions
4080 Display function names as well as file and line number information.
4081
4082 @item -s
4083 @itemx --basenames
4084 Display only the base of each file name.
4085
4086 @item -i
4087 @itemx --inlines
4088 If the address belongs to a function that was inlined, the source
4089 information for all enclosing scopes back to the first non-inlined
4090 function will also be printed. For example, if @code{main} inlines
4091 @code{callee1} which inlines @code{callee2}, and address is from
4092 @code{callee2}, the source information for @code{callee1} and @code{main}
4093 will also be printed.
4094
4095 @item -j
4096 @itemx --section
4097 Read offsets relative to the specified section instead of absolute addresses.
4098
4099 @item -p
4100 @itemx --pretty-print
4101 Make the output more human friendly: each location are printed on one line.
4102 If option @option{-i} is specified, lines for all enclosing scopes are
4103 prefixed with @samp{(inlined by)}.
4104
4105 @item -r
4106 @itemx -R
4107 @itemx --recurse-limit
4108 @itemx --no-recurse-limit
4109 @itemx --recursion-limit
4110 @itemx --no-recursion-limit
4111 Enables or disables a limit on the amount of recursion performed
4112 whilst demangling strings. Since the name mangling formats allow for
4113 an infinite level of recursion it is possible to create strings whose
4114 decoding will exhaust the amount of stack space available on the host
4115 machine, triggering a memory fault. The limit tries to prevent this
4116 from happening by restricting recursion to 2048 levels of nesting.
4117
4118 The default is for this limit to be enabled, but disabling it may be
4119 necessary in order to demangle truly complicated names. Note however
4120 that if the recursion limit is disabled then stack exhaustion is
4121 possible and any bug reports about such an event will be rejected.
4122
4123 The @option{-r} option is a synonym for the
4124 @option{--no-recurse-limit} option. The @option{-R} option is a
4125 synonym for the @option{--recurse-limit} option.
4126
4127 Note this option is only effective if the @option{-C} or
4128 @option{--demangle} option has been enabled.
4129
4130 @end table
4131
4132 @c man end
4133
4134 @ignore
4135 @c man begin SEEALSO addr2line
4136 Info entries for @file{binutils}.
4137 @c man end
4138 @end ignore
4139
4140 @node windmc
4141 @chapter windmc
4142
4143 @command{windmc} may be used to generator Windows message resources.
4144
4145 @quotation
4146 @emph{Warning:} @command{windmc} is not always built as part of the binary
4147 utilities, since it is only useful for Windows targets.
4148 @end quotation
4149
4150 @c man title windmc generates Windows message resources
4151
4152 @smallexample
4153 @c man begin SYNOPSIS windmc
4154 windmc [options] input-file
4155 @c man end
4156 @end smallexample
4157
4158 @c man begin DESCRIPTION windmc
4159
4160 @command{windmc} reads message definitions from an input file (.mc) and
4161 translate them into a set of output files. The output files may be of
4162 four kinds:
4163
4164 @table @code
4165 @item h
4166 A C header file containing the message definitions.
4167
4168 @item rc
4169 A resource file compilable by the @command{windres} tool.
4170
4171 @item bin
4172 One or more binary files containing the resource data for a specific
4173 message language.
4174
4175 @item dbg
4176 A C include file that maps message id's to their symbolic name.
4177 @end table
4178
4179 The exact description of these different formats is available in
4180 documentation from Microsoft.
4181
4182 When @command{windmc} converts from the @code{mc} format to the @code{bin}
4183 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
4184 Windows Message Compiler.
4185
4186 @c man end
4187
4188 @c man begin OPTIONS windmc
4189
4190 @table @env
4191 @item -a
4192 @itemx --ascii_in
4193 Specifies that the input file specified is ASCII. This is the default
4194 behaviour.
4195
4196 @item -A
4197 @itemx --ascii_out
4198 Specifies that messages in the output @code{bin} files should be in ASCII
4199 format.
4200
4201 @item -b
4202 @itemx --binprefix
4203 Specifies that @code{bin} filenames should have to be prefixed by the
4204 basename of the source file.
4205
4206 @item -c
4207 @itemx --customflag
4208 Sets the customer bit in all message id's.
4209
4210 @item -C @var{codepage}
4211 @itemx --codepage_in @var{codepage}
4212 Sets the default codepage to be used to convert input file to UTF16. The
4213 default is ocdepage 1252.
4214
4215 @item -d
4216 @itemx --decimal_values
4217 Outputs the constants in the header file in decimal. Default is using
4218 hexadecimal output.
4219
4220 @item -e @var{ext}
4221 @itemx --extension @var{ext}
4222 The extension for the header file. The default is .h extension.
4223
4224 @item -F @var{target}
4225 @itemx --target @var{target}
4226 Specify the BFD format to use for a bin file as output. This
4227 is a BFD target name; you can use the @option{--help} option to see a list
4228 of supported targets. Normally @command{windmc} will use the default
4229 format, which is the first one listed by the @option{--help} option.
4230 @ifclear man
4231 @ref{Target Selection}.
4232 @end ifclear
4233
4234 @item -h @var{path}
4235 @itemx --headerdir @var{path}
4236 The target directory of the generated header file. The default is the
4237 current directory.
4238
4239 @item -H
4240 @itemx --help
4241 Displays a list of command-line options and then exits.
4242
4243 @item -m @var{characters}
4244 @itemx --maxlength @var{characters}
4245 Instructs @command{windmc} to generate a warning if the length
4246 of any message exceeds the number specified.
4247
4248 @item -n
4249 @itemx --nullterminate
4250 Terminate message text in @code{bin} files by zero. By default they are
4251 terminated by CR/LF.
4252
4253 @item -o
4254 @itemx --hresult_use
4255 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4256 file, using HRESULT definitions. Status codes are used if the flag is not
4257 specified.
4258
4259 @item -O @var{codepage}
4260 @itemx --codepage_out @var{codepage}
4261 Sets the default codepage to be used to output text files. The default
4262 is ocdepage 1252.
4263
4264 @item -r @var{path}
4265 @itemx --rcdir @var{path}
4266 The target directory for the generated @code{rc} script and the generated
4267 @code{bin} files that the resource compiler script includes. The default
4268 is the current directory.
4269
4270 @item -u
4271 @itemx --unicode_in
4272 Specifies that the input file is UTF16.
4273
4274 @item -U
4275 @itemx --unicode_out
4276 Specifies that messages in the output @code{bin} file should be in UTF16
4277 format. This is the default behaviour.
4278
4279 @item -v
4280 @item --verbose
4281 Enable verbose mode.
4282
4283 @item -V
4284 @item --version
4285 Prints the version number for @command{windmc}.
4286
4287 @item -x @var{path}
4288 @itemx --xdgb @var{path}
4289 The path of the @code{dbg} C include file that maps message id's to the
4290 symbolic name. No such file is generated without specifying the switch.
4291 @end table
4292
4293 @c man end
4294
4295 @ignore
4296 @c man begin SEEALSO windmc
4297 the Info entries for @file{binutils}.
4298 @c man end
4299 @end ignore
4300
4301 @node windres
4302 @chapter windres
4303
4304 @command{windres} may be used to manipulate Windows resources.
4305
4306 @quotation
4307 @emph{Warning:} @command{windres} is not always built as part of the binary
4308 utilities, since it is only useful for Windows targets.
4309 @end quotation
4310
4311 @c man title windres manipulate Windows resources
4312
4313 @smallexample
4314 @c man begin SYNOPSIS windres
4315 windres [options] [input-file] [output-file]
4316 @c man end
4317 @end smallexample
4318
4319 @c man begin DESCRIPTION windres
4320
4321 @command{windres} reads resources from an input file and copies them into
4322 an output file. Either file may be in one of three formats:
4323
4324 @table @code
4325 @item rc
4326 A text format read by the Resource Compiler.
4327
4328 @item res
4329 A binary format generated by the Resource Compiler.
4330
4331 @item coff
4332 A COFF object or executable.
4333 @end table
4334
4335 The exact description of these different formats is available in
4336 documentation from Microsoft.
4337
4338 When @command{windres} converts from the @code{rc} format to the @code{res}
4339 format, it is acting like the Windows Resource Compiler. When
4340 @command{windres} converts from the @code{res} format to the @code{coff}
4341 format, it is acting like the Windows @code{CVTRES} program.
4342
4343 When @command{windres} generates an @code{rc} file, the output is similar
4344 but not identical to the format expected for the input. When an input
4345 @code{rc} file refers to an external filename, an output @code{rc} file
4346 will instead include the file contents.
4347
4348 If the input or output format is not specified, @command{windres} will
4349 guess based on the file name, or, for the input file, the file contents.
4350 A file with an extension of @file{.rc} will be treated as an @code{rc}
4351 file, a file with an extension of @file{.res} will be treated as a
4352 @code{res} file, and a file with an extension of @file{.o} or
4353 @file{.exe} will be treated as a @code{coff} file.
4354
4355 If no output file is specified, @command{windres} will print the resources
4356 in @code{rc} format to standard output.
4357
4358 The normal use is for you to write an @code{rc} file, use @command{windres}
4359 to convert it to a COFF object file, and then link the COFF file into
4360 your application. This will make the resources described in the
4361 @code{rc} file available to Windows.
4362
4363 @c man end
4364
4365 @c man begin OPTIONS windres
4366
4367 @table @env
4368 @item -i @var{filename}
4369 @itemx --input @var{filename}
4370 The name of the input file. If this option is not used, then
4371 @command{windres} will use the first non-option argument as the input file
4372 name. If there are no non-option arguments, then @command{windres} will
4373 read from standard input. @command{windres} can not read a COFF file from
4374 standard input.
4375
4376 @item -o @var{filename}
4377 @itemx --output @var{filename}
4378 The name of the output file. If this option is not used, then
4379 @command{windres} will use the first non-option argument, after any used
4380 for the input file name, as the output file name. If there is no
4381 non-option argument, then @command{windres} will write to standard output.
4382 @command{windres} can not write a COFF file to standard output. Note,
4383 for compatibility with @command{rc} the option @option{-fo} is also
4384 accepted, but its use is not recommended.
4385
4386 @item -J @var{format}
4387 @itemx --input-format @var{format}
4388 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4389 @samp{coff}. If no input format is specified, @command{windres} will
4390 guess, as described above.
4391
4392 @item -O @var{format}
4393 @itemx --output-format @var{format}
4394 The output format to generate. @var{format} may be @samp{res},
4395 @samp{rc}, or @samp{coff}. If no output format is specified,
4396 @command{windres} will guess, as described above.
4397
4398 @item -F @var{target}
4399 @itemx --target @var{target}
4400 Specify the BFD format to use for a COFF file as input or output. This
4401 is a BFD target name; you can use the @option{--help} option to see a list
4402 of supported targets. Normally @command{windres} will use the default
4403 format, which is the first one listed by the @option{--help} option.
4404 @ifclear man
4405 @ref{Target Selection}.
4406 @end ifclear
4407
4408 @item --preprocessor @var{program}
4409 When @command{windres} reads an @code{rc} file, it runs it through the C
4410 preprocessor first. This option may be used to specify the preprocessor
4411 to use. The default preprocessor is @code{gcc}.
4412
4413 @item --preprocessor-arg @var{option}
4414 When @command{windres} reads an @code{rc} file, it runs it through
4415 the C preprocessor first. This option may be used to specify additional
4416 text to be passed to preprocessor on its command line.
4417 This option can be used multiple times to add multiple options to the
4418 preprocessor command line.
4419 If the @option{--preprocessor} option has not been specified then a
4420 default set of preprocessor arguments will be used, with any
4421 @option{--preprocessor-arg} options being placed after them on the
4422 command line. These default arguments are @code{-E},
4423 @code{-xc-header} and @code{-DRC_INVOKED}.
4424
4425 @item -I @var{directory}
4426 @itemx --include-dir @var{directory}
4427 Specify an include directory to use when reading an @code{rc} file.
4428 @command{windres} will pass this to the preprocessor as an @option{-I}
4429 option. @command{windres} will also search this directory when looking for
4430 files named in the @code{rc} file. If the argument passed to this command
4431 matches any of the supported @var{formats} (as described in the @option{-J}
4432 option), it will issue a deprecation warning, and behave just like the
4433 @option{-J} option. New programs should not use this behaviour. If a
4434 directory happens to match a @var{format}, simple prefix it with @samp{./}
4435 to disable the backward compatibility.
4436
4437 @item -D @var{target}
4438 @itemx --define @var{sym}[=@var{val}]
4439 Specify a @option{-D} option to pass to the preprocessor when reading an
4440 @code{rc} file.
4441
4442 @item -U @var{target}
4443 @itemx --undefine @var{sym}
4444 Specify a @option{-U} option to pass to the preprocessor when reading an
4445 @code{rc} file.
4446
4447 @item -r
4448 Ignored for compatibility with rc.
4449
4450 @item -v
4451 Enable verbose mode. This tells you what the preprocessor is if you
4452 didn't specify one.
4453
4454 @item -c @var{val}
4455 @item --codepage @var{val}
4456 Specify the default codepage to use when reading an @code{rc} file.
4457 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4458 codepage code. The valid range is from zero up to 0xffff, but the
4459 validity of the codepage is host and configuration dependent.
4460
4461 @item -l @var{val}
4462 @item --language @var{val}
4463 Specify the default language to use when reading an @code{rc} file.
4464 @var{val} should be a hexadecimal language code. The low eight bits are
4465 the language, and the high eight bits are the sublanguage.
4466
4467 @item --use-temp-file
4468 Use a temporary file to instead of using popen to read the output of
4469 the preprocessor. Use this option if the popen implementation is buggy
4470 on the host (eg., certain non-English language versions of Windows 95 and
4471 Windows 98 are known to have buggy popen where the output will instead
4472 go the console).
4473
4474 @item --no-use-temp-file
4475 Use popen, not a temporary file, to read the output of the preprocessor.
4476 This is the default behaviour.
4477
4478 @item -h
4479 @item --help
4480 Prints a usage summary.
4481
4482 @item -V
4483 @item --version
4484 Prints the version number for @command{windres}.
4485
4486 @item --yydebug
4487 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4488 this will turn on parser debugging.
4489 @end table
4490
4491 @c man end
4492
4493 @ignore
4494 @c man begin SEEALSO windres
4495 the Info entries for @file{binutils}.
4496 @c man end
4497 @end ignore
4498
4499 @node dlltool
4500 @chapter dlltool
4501 @cindex DLL
4502 @kindex dlltool
4503
4504 @command{dlltool} is used to create the files needed to create dynamic
4505 link libraries (DLLs) on systems which understand PE format image
4506 files such as Windows. A DLL contains an export table which contains
4507 information that the runtime loader needs to resolve references from a
4508 referencing program.
4509
4510 The export table is generated by this program by reading in a
4511 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4512 will be in the DLL. A @file{.o} file can contain information in
4513 special @samp{.drectve} sections with export information.
4514
4515 @quotation
4516 @emph{Note:} @command{dlltool} is not always built as part of the
4517 binary utilities, since it is only useful for those targets which
4518 support DLLs.
4519 @end quotation
4520
4521 @c man title dlltool create files needed to build and use DLLs
4522
4523 @smallexample
4524 @c man begin SYNOPSIS dlltool
4525 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4526 [@option{-b}|@option{--base-file} @var{base-file-name}]
4527 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4528 [@option{-z}|@option{--output-def} @var{def-file-name}]
4529 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4530 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4531 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4532 [@option{--exclude-symbols} @var{list}]
4533 [@option{--no-default-excludes}]
4534 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4535 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4536 [@option{-a}|@option{--add-indirect}]
4537 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4538 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4539 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4540 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4541 [@option{--use-nul-prefixed-import-tables}]
4542 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4543 [@option{-i}|@option{--interwork}]
4544 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4545 [@option{-v}|@option{--verbose}]
4546 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4547 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4548 [@option{--deterministic-libraries}] [@option{--non-deterministic-libraries}]
4549 [object-file @dots{}]
4550 @c man end
4551 @end smallexample
4552
4553 @c man begin DESCRIPTION dlltool
4554
4555 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4556 @option{-b} options as well as object files specified on the command
4557 line. It then processes these inputs and if the @option{-e} option has
4558 been specified it creates a exports file. If the @option{-l} option
4559 has been specified it creates a library file and if the @option{-z} option
4560 has been specified it creates a def file. Any or all of the @option{-e},
4561 @option{-l} and @option{-z} options can be present in one invocation of
4562 dlltool.
4563
4564 When creating a DLL, along with the source for the DLL, it is necessary
4565 to have three other files. @command{dlltool} can help with the creation of
4566 these files.
4567
4568 The first file is a @file{.def} file which specifies which functions are
4569 exported from the DLL, which functions the DLL imports, and so on. This
4570 is a text file and can be created by hand, or @command{dlltool} can be used
4571 to create it using the @option{-z} option. In this case @command{dlltool}
4572 will scan the object files specified on its command line looking for
4573 those functions which have been specially marked as being exported and
4574 put entries for them in the @file{.def} file it creates.
4575
4576 In order to mark a function as being exported from a DLL, it needs to
4577 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4578 section of the object file. This can be done in C by using the
4579 asm() operator:
4580
4581 @smallexample
4582 asm (".section .drectve");
4583 asm (".ascii \"-export:my_func\"");
4584
4585 int my_func (void) @{ @dots{} @}
4586 @end smallexample
4587
4588 The second file needed for DLL creation is an exports file. This file
4589 is linked with the object files that make up the body of the DLL and it
4590 handles the interface between the DLL and the outside world. This is a
4591 binary file and it can be created by giving the @option{-e} option to
4592 @command{dlltool} when it is creating or reading in a @file{.def} file.
4593
4594 The third file needed for DLL creation is the library file that programs
4595 will link with in order to access the functions in the DLL (an `import
4596 library'). This file can be created by giving the @option{-l} option to
4597 dlltool when it is creating or reading in a @file{.def} file.
4598
4599 If the @option{-y} option is specified, dlltool generates a delay-import
4600 library that can be used instead of the normal import library to allow
4601 a program to link to the dll only as soon as an imported function is
4602 called for the first time. The resulting executable will need to be
4603 linked to the static delayimp library containing __delayLoadHelper2(),
4604 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4605
4606 @command{dlltool} builds the library file by hand, but it builds the
4607 exports file by creating temporary files containing assembler statements
4608 and then assembling these. The @option{-S} command-line option can be
4609 used to specify the path to the assembler that dlltool will use,
4610 and the @option{-f} option can be used to pass specific flags to that
4611 assembler. The @option{-n} can be used to prevent dlltool from deleting
4612 these temporary assembler files when it is done, and if @option{-n} is
4613 specified twice then this will prevent dlltool from deleting the
4614 temporary object files it used to build the library.
4615
4616 Here is an example of creating a DLL from a source file @samp{dll.c} and
4617 also creating a program (from an object file called @samp{program.o})
4618 that uses that DLL:
4619
4620 @smallexample
4621 gcc -c dll.c
4622 dlltool -e exports.o -l dll.lib dll.o
4623 gcc dll.o exports.o -o dll.dll
4624 gcc program.o dll.lib -o program
4625 @end smallexample
4626
4627
4628 @command{dlltool} may also be used to query an existing import library
4629 to determine the name of the DLL to which it is associated. See the
4630 description of the @option{-I} or @option{--identify} option.
4631
4632 @c man end
4633
4634 @c man begin OPTIONS dlltool
4635
4636 The command-line options have the following meanings:
4637
4638 @table @env
4639
4640 @item -d @var{filename}
4641 @itemx --input-def @var{filename}
4642 @cindex input .def file
4643 Specifies the name of a @file{.def} file to be read in and processed.
4644
4645 @item -b @var{filename}
4646 @itemx --base-file @var{filename}
4647 @cindex base files
4648 Specifies the name of a base file to be read in and processed. The
4649 contents of this file will be added to the relocation section in the
4650 exports file generated by dlltool.
4651
4652 @item -e @var{filename}
4653 @itemx --output-exp @var{filename}
4654 Specifies the name of the export file to be created by dlltool.
4655
4656 @item -z @var{filename}
4657 @itemx --output-def @var{filename}
4658 Specifies the name of the @file{.def} file to be created by dlltool.
4659
4660 @item -l @var{filename}
4661 @itemx --output-lib @var{filename}
4662 Specifies the name of the library file to be created by dlltool.
4663
4664 @item -y @var{filename}
4665 @itemx --output-delaylib @var{filename}
4666 Specifies the name of the delay-import library file to be created by dlltool.
4667
4668 @item --deterministic-libraries
4669 @itemx --non-deterministic-libraries
4670 When creating output libraries in response to either the
4671 @option{--output-lib} or @option{--output-delaylib} options either use
4672 the value of zero for any timestamps, user ids and group ids created
4673 (@option{--deterministic-libraries}) or the actual timestamps, user
4674 ids and group ids (@option{--non-deterministic-libraries}).
4675
4676 @item --export-all-symbols
4677 Treat all global and weak defined symbols found in the input object
4678 files as symbols to be exported. There is a small list of symbols which
4679 are not exported by default; see the @option{--no-default-excludes}
4680 option. You may add to the list of symbols to not export by using the
4681 @option{--exclude-symbols} option.
4682
4683 @item --no-export-all-symbols
4684 Only export symbols explicitly listed in an input @file{.def} file or in
4685 @samp{.drectve} sections in the input object files. This is the default
4686 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4687 attributes in the source code.
4688
4689 @item --exclude-symbols @var{list}
4690 Do not export the symbols in @var{list}. This is a list of symbol names
4691 separated by comma or colon characters. The symbol names should not
4692 contain a leading underscore. This is only meaningful when
4693 @option{--export-all-symbols} is used.
4694
4695 @item --no-default-excludes
4696 When @option{--export-all-symbols} is used, it will by default avoid
4697 exporting certain special symbols. The current list of symbols to avoid
4698 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4699 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4700 to go ahead and export these special symbols. This is only meaningful
4701 when @option{--export-all-symbols} is used.
4702
4703 @item -S @var{path}
4704 @itemx --as @var{path}
4705 Specifies the path, including the filename, of the assembler to be used
4706 to create the exports file.
4707
4708 @item -f @var{options}
4709 @itemx --as-flags @var{options}
4710 Specifies any specific command-line options to be passed to the
4711 assembler when building the exports file. This option will work even if
4712 the @option{-S} option is not used. This option only takes one argument,
4713 and if it occurs more than once on the command line, then later
4714 occurrences will override earlier occurrences. So if it is necessary to
4715 pass multiple options to the assembler they should be enclosed in
4716 double quotes.
4717
4718 @item -D @var{name}
4719 @itemx --dll-name @var{name}
4720 Specifies the name to be stored in the @file{.def} file as the name of
4721 the DLL when the @option{-e} option is used. If this option is not
4722 present, then the filename given to the @option{-e} option will be
4723 used as the name of the DLL.
4724
4725 @item -m @var{machine}
4726 @itemx -machine @var{machine}
4727 Specifies the type of machine for which the library file should be
4728 built. @command{dlltool} has a built in default type, depending upon how
4729 it was created, but this option can be used to override that. This is
4730 normally only useful when creating DLLs for an ARM processor, when the
4731 contents of the DLL are actually encode using Thumb instructions.
4732
4733 @item -a
4734 @itemx --add-indirect
4735 Specifies that when @command{dlltool} is creating the exports file it
4736 should add a section which allows the exported functions to be
4737 referenced without using the import library. Whatever the hell that
4738 means!
4739
4740 @item -U
4741 @itemx --add-underscore
4742 Specifies that when @command{dlltool} is creating the exports file it
4743 should prepend an underscore to the names of @emph{all} exported symbols.
4744
4745 @item --no-leading-underscore
4746 @item --leading-underscore
4747 Specifies whether standard symbol should be forced to be prefixed, or
4748 not.
4749
4750 @item --add-stdcall-underscore
4751 Specifies that when @command{dlltool} is creating the exports file it
4752 should prepend an underscore to the names of exported @emph{stdcall}
4753 functions. Variable names and non-stdcall function names are not modified.
4754 This option is useful when creating GNU-compatible import libs for third
4755 party DLLs that were built with MS-Windows tools.
4756
4757 @item -k
4758 @itemx --kill-at
4759 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4760 of stdcall functions that will be imported from the DLL. This is
4761 useful when creating an import library for a DLL which exports stdcall
4762 functions but without the usual @samp{@@<number>} symbol name suffix.
4763
4764 This does not change the naming of symbols provided by the import library
4765 to programs linked against it, but only the entries in the import table
4766 (ie the .idata section).
4767
4768 @item -A
4769 @itemx --add-stdcall-alias
4770 Specifies that when @command{dlltool} is creating the exports file it
4771 should add aliases for stdcall symbols without @samp{@@ <number>}
4772 in addition to the symbols with @samp{@@ <number>}.
4773
4774 @item -p
4775 @itemx --ext-prefix-alias @var{prefix}
4776 Causes @command{dlltool} to create external aliases for all DLL
4777 imports with the specified prefix. The aliases are created for both
4778 external and import symbols with no leading underscore.
4779
4780 @item -x
4781 @itemx --no-idata4
4782 Specifies that when @command{dlltool} is creating the exports and library
4783 files it should omit the @code{.idata4} section. This is for compatibility
4784 with certain operating systems.
4785
4786 @item --use-nul-prefixed-import-tables
4787 Specifies that when @command{dlltool} is creating the exports and library
4788 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4789 element. This emulates old gnu import library generation of
4790 @code{dlltool}. By default this option is turned off.
4791
4792 @item -c
4793 @itemx --no-idata5
4794 Specifies that when @command{dlltool} is creating the exports and library
4795 files it should omit the @code{.idata5} section. This is for compatibility
4796 with certain operating systems.
4797
4798 @item -I @var{filename}
4799 @itemx --identify @var{filename}
4800 Specifies that @command{dlltool} should inspect the import library
4801 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4802 of the associated DLL(s). This can be performed in addition to any
4803 other operations indicated by the other options and arguments.
4804 @command{dlltool} fails if the import library does not exist or is not
4805 actually an import library. See also @option{--identify-strict}.
4806
4807 @item --identify-strict
4808 Modifies the behavior of the @option{--identify} option, such
4809 that an error is reported if @var{filename} is associated with
4810 more than one DLL.
4811
4812 @item -i
4813 @itemx --interwork
4814 Specifies that @command{dlltool} should mark the objects in the library
4815 file and exports file that it produces as supporting interworking
4816 between ARM and Thumb code.
4817
4818 @item -n
4819 @itemx --nodelete
4820 Makes @command{dlltool} preserve the temporary assembler files it used to
4821 create the exports file. If this option is repeated then dlltool will
4822 also preserve the temporary object files it uses to create the library
4823 file.
4824
4825 @item -t @var{prefix}
4826 @itemx --temp-prefix @var{prefix}
4827 Makes @command{dlltool} use @var{prefix} when constructing the names of
4828 temporary assembler and object files. By default, the temp file prefix
4829 is generated from the pid.
4830
4831 @item -v
4832 @itemx --verbose
4833 Make dlltool describe what it is doing.
4834
4835 @item -h
4836 @itemx --help
4837 Displays a list of command-line options and then exits.
4838
4839 @item -V
4840 @itemx --version
4841 Displays dlltool's version number and then exits.
4842
4843 @end table
4844
4845 @c man end
4846
4847 @menu
4848 * def file format:: The format of the dlltool @file{.def} file
4849 @end menu
4850
4851 @node def file format
4852 @section The format of the @command{dlltool} @file{.def} file
4853
4854 A @file{.def} file contains any number of the following commands:
4855
4856 @table @asis
4857
4858 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4859 The result is going to be named @var{name}@code{.exe}.
4860
4861 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4862 The result is going to be named @var{name}@code{.dll}.
4863 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4864 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4865 details).
4866
4867 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4868 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4869 Declares @var{name1} as an exported symbol from the DLL, with optional
4870 ordinal number @var{integer}, or declares @var{name1} as an alias
4871 (forward) of the function @var{external-name} in the DLL.
4872 If @var{its_name} is specified, this name is used as string in export table.
4873 @var{module-name}.
4874 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4875 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4876 If you want to use LIBRARY as name then you need to quote it.
4877
4878 @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{]} *}
4879 Declares that @var{external-name} or the exported function whose
4880 ordinal number is @var{integer} is to be imported from the file
4881 @var{module-name}. If @var{internal-name} is specified then this is
4882 the name that the imported function will be referred to in the body of
4883 the DLL.
4884 If @var{its_name} is specified, this name is used as string in import table.
4885 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4886 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4887 If you want to use LIBRARY as name then you need to quote it.
4888
4889 @item @code{DESCRIPTION} @var{string}
4890 Puts @var{string} into the output @file{.exp} file in the
4891 @code{.rdata} section.
4892
4893 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4894 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4895 Generates @code{--stack} or @code{--heap}
4896 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4897 section. The linker will see this and act upon it.
4898
4899 @item @code{CODE} @var{attr} @code{+}
4900 @item @code{DATA} @var{attr} @code{+}
4901 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4902 Generates @code{--attr} @var{section-name} @var{attr} in the output
4903 @code{.drectve} section, where @var{attr} is one of @code{READ},
4904 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4905 this and act upon it.
4906
4907 @end table
4908
4909 @ignore
4910 @c man begin SEEALSO dlltool
4911 The Info pages for @file{binutils}.
4912 @c man end
4913 @end ignore
4914
4915 @node readelf
4916 @chapter readelf
4917
4918 @cindex ELF file information
4919 @kindex readelf
4920
4921 @c man title readelf display information about ELF files
4922
4923 @smallexample
4924 @c man begin SYNOPSIS readelf
4925 readelf [@option{-a}|@option{--all}]
4926 [@option{-h}|@option{--file-header}]
4927 [@option{-l}|@option{--program-headers}|@option{--segments}]
4928 [@option{-S}|@option{--section-headers}|@option{--sections}]
4929 [@option{-g}|@option{--section-groups}]
4930 [@option{-t}|@option{--section-details}]
4931 [@option{-e}|@option{--headers}]
4932 [@option{-s}|@option{--syms}|@option{--symbols}]
4933 [@option{--dyn-syms}|@option{--lto-syms}]
4934 [@option{--sym-base=[0|8|10|16]}]
4935 [@option{--demangle@var{=style}}|@option{--no-demangle}]
4936 [@option{--quiet}]
4937 [@option{--recurse-limit}|@option{--no-recurse-limit}]
4938 [@option{-U} @var{method}|@option{--unicode=}@var{method}]
4939 [@option{-n}|@option{--notes}]
4940 [@option{-r}|@option{--relocs}]
4941 [@option{-u}|@option{--unwind}]
4942 [@option{-d}|@option{--dynamic}]
4943 [@option{-V}|@option{--version-info}]
4944 [@option{-A}|@option{--arch-specific}]
4945 [@option{-D}|@option{--use-dynamic}]
4946 [@option{-L}|@option{--lint}|@option{--enable-checks}]
4947 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4948 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4949 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4950 [@option{-z}|@option{--decompress}]
4951 [@option{-c}|@option{--archive-index}]
4952 [@option{-w[lLiaprmfFsoORtUuTgAck]}|
4953 @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]]
4954 [@option{-wK}|@option{--debug-dump=follow-links}]
4955 [@option{-wN}|@option{--debug-dump=no-follow-links}]
4956 [@option{-wD}|@option{--debug-dump=use-debuginfod}]
4957 [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
4958 [@option{-P}|@option{--process-links}]
4959 [@option{--dwarf-depth=@var{n}}]
4960 [@option{--dwarf-start=@var{n}}]
4961 [@option{--ctf=}@var{section}]
4962 [@option{--ctf-parent=}@var{section}]
4963 [@option{--ctf-symbols=}@var{section}]
4964 [@option{--ctf-strings=}@var{section}]
4965 [@option{--sframe=}@var{section}]
4966 [@option{-I}|@option{--histogram}]
4967 [@option{-v}|@option{--version}]
4968 [@option{-W}|@option{--wide}]
4969 [@option{-T}|@option{--silent-truncation}]
4970 [@option{-H}|@option{--help}]
4971 @var{elffile}@dots{}
4972 @c man end
4973 @end smallexample
4974
4975 @c man begin DESCRIPTION readelf
4976
4977 @command{readelf} displays information about one or more ELF format object
4978 files. The options control what particular information to display.
4979
4980 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4981 64-bit ELF files are supported, as are archives containing ELF files.
4982
4983 This program performs a similar function to @command{objdump} but it
4984 goes into more detail and it exists independently of the @sc{bfd}
4985 library, so if there is a bug in @sc{bfd} then readelf will not be
4986 affected.
4987
4988 @c man end
4989
4990 @c man begin OPTIONS readelf
4991
4992 The long and short forms of options, shown here as alternatives, are
4993 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4994 given.
4995
4996 @table @env
4997 @item -a
4998 @itemx --all
4999 Equivalent to specifying @option{--file-header},
5000 @option{--program-headers}, @option{--sections}, @option{--symbols},
5001 @option{--relocs}, @option{--dynamic}, @option{--notes},
5002 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
5003 @option{--section-groups} and @option{--histogram}.
5004
5005 Note - this option does not enable @option{--use-dynamic} itself, so
5006 if that option is not present on the command line then dynamic symbols
5007 and dynamic relocs will not be displayed.
5008
5009 @item -h
5010 @itemx --file-header
5011 @cindex ELF file header information
5012 Displays the information contained in the ELF header at the start of the
5013 file.
5014
5015 @item -l
5016 @itemx --program-headers
5017 @itemx --segments
5018 @cindex ELF program header information
5019 @cindex ELF segment information
5020 Displays the information contained in the file's segment headers, if it
5021 has any.
5022
5023 @item --quiet
5024 @cindex quiet
5025 Suppress "no symbols" diagnostic.
5026
5027 @item -S
5028 @itemx --sections
5029 @itemx --section-headers
5030 @cindex ELF section information
5031 Displays the information contained in the file's section headers, if it
5032 has any.
5033
5034 @item -g
5035 @itemx --section-groups
5036 @cindex ELF section group information
5037 Displays the information contained in the file's section groups, if it
5038 has any.
5039
5040 @item -t
5041 @itemx --section-details
5042 @cindex ELF section information
5043 Displays the detailed section information. Implies @option{-S}.
5044
5045 @item -s
5046 @itemx --symbols
5047 @itemx --syms
5048 @cindex ELF symbol table information
5049 Displays the entries in symbol table section of the file, if it has one.
5050 If a symbol has version information associated with it then this is
5051 displayed as well. The version string is displayed as a suffix to the
5052 symbol name, preceded by an @@ character. For example
5053 @samp{foo@@VER_1}. If the version is the default version to be used
5054 when resolving unversioned references to the symbol then it is
5055 displayed as a suffix preceded by two @@ characters. For example
5056 @samp{foo@@@@VER_2}.
5057
5058 @item --dyn-syms
5059 @cindex ELF dynamic symbol table information
5060 Displays the entries in dynamic symbol table section of the file, if it
5061 has one. The output format is the same as the format used by the
5062 @option{--syms} option.
5063
5064 @item --lto-syms
5065 @cindex LTO symbol table
5066 Displays the contents of any LTO symbol tables in the file.
5067
5068 @item --sym-base=[0|8|10|16]
5069 @cindex symbol table size base
5070 Forces the size field of the symbol table to use the given base. Any
5071 unrecognized options will be treated as @samp{0}. @option{--sym-base=0}
5072 represents the default and legacy behaviour. This will output sizes as decimal
5073 for numbers less than 100000. For sizes 100000 and greater hexadecimal notation
5074 will be used with a 0x prefix.
5075 @option{--sym-base=8} will give the symbol sizes in octal.
5076 @option{--sym-base=10} will always give the symbol sizes in decimal.
5077 @option{--sym-base=16} will always give the symbol sizes in hexadecimal with a
5078 0x prefix.
5079
5080 @item -C
5081 @itemx --demangle[=@var{style}]
5082 @cindex demangling in nm
5083 Decode (@dfn{demangle}) low-level symbol names into user-level names.
5084 This makes C++ function names readable. Different compilers have
5085 different mangling styles. The optional demangling style argument can
5086 be used to choose an appropriate demangling style for your
5087 compiler. @xref{c++filt}, for more information on demangling.
5088
5089 @item --no-demangle
5090 Do not demangle low-level symbol names. This is the default.
5091
5092 @item --recurse-limit
5093 @itemx --no-recurse-limit
5094 @itemx --recursion-limit
5095 @itemx --no-recursion-limit
5096 Enables or disables a limit on the amount of recursion performed
5097 whilst demangling strings. Since the name mangling formats allow for
5098 an infinite level of recursion it is possible to create strings whose
5099 decoding will exhaust the amount of stack space available on the host
5100 machine, triggering a memory fault. The limit tries to prevent this
5101 from happening by restricting recursion to 2048 levels of nesting.
5102
5103 The default is for this limit to be enabled, but disabling it may be
5104 necessary in order to demangle truly complicated names. Note however
5105 that if the recursion limit is disabled then stack exhaustion is
5106 possible and any bug reports about such an event will be rejected.
5107
5108 @item -U @var{[d|i|l|e|x|h]}
5109 @itemx --unicode=[default|invalid|locale|escape|hex|highlight]
5110 Controls the display of non-ASCII characters in identifier names.
5111 The default (@option{--unicode=locale} or @option{--unicode=default}) is
5112 to treat them as multibyte characters and display them in the current
5113 locale. All other versions of this option treat the bytes as UTF-8
5114 encoded values and attempt to interpret them. If they cannot be
5115 interpreted or if the @option{--unicode=invalid} option is used then
5116 they are displayed as a sequence of hex bytes, encloses in curly
5117 parethesis characters.
5118
5119 Using the @option{--unicode=escape} option will display the characters
5120 as as unicode escape sequences (@var{\uxxxx}). Using the
5121 @option{--unicode=hex} will display the characters as hex byte
5122 sequences enclosed between angle brackets.
5123
5124 Using the @option{--unicode=highlight} will display the characters as
5125 unicode escape sequences but it will also highlighted them in red,
5126 assuming that colouring is supported by the output device. The
5127 colouring is intended to draw attention to the presence of unicode
5128 sequences when they might not be expected.
5129
5130 @item -e
5131 @itemx --headers
5132 Display all the headers in the file. Equivalent to @option{-h -l -S}.
5133
5134 @item -n
5135 @itemx --notes
5136 @cindex ELF notes
5137 Displays the contents of the NOTE segments and/or sections, if any.
5138
5139 @item -r
5140 @itemx --relocs
5141 @cindex ELF reloc information
5142 Displays the contents of the file's relocation section, if it has one.
5143
5144 @item -u
5145 @itemx --unwind
5146 @cindex unwind information
5147 Displays the contents of the file's unwind section, if it has one. Only
5148 the unwind sections for IA64 ELF files, as well as ARM unwind tables
5149 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
5150 support is not yet implemented for your architecture you could try
5151 dumping the contents of the @var{.eh_frames} section using the
5152 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
5153 options.
5154
5155 @item -d
5156 @itemx --dynamic
5157 @cindex ELF dynamic section information
5158 Displays the contents of the file's dynamic section, if it has one.
5159
5160 @item -V
5161 @itemx --version-info
5162 @cindex ELF version sections information
5163 Displays the contents of the version sections in the file, it they
5164 exist.
5165
5166 @item -A
5167 @itemx --arch-specific
5168 Displays architecture-specific information in the file, if there
5169 is any.
5170
5171 @item -D
5172 @itemx --use-dynamic
5173 When displaying symbols, this option makes @command{readelf} use the
5174 symbol hash tables in the file's dynamic section, rather than the
5175 symbol table sections.
5176
5177 When displaying relocations, this option makes @command{readelf}
5178 display the dynamic relocations rather than the static relocations.
5179
5180 @item -L
5181 @itemx --lint
5182 @itemx --enable-checks
5183 Displays warning messages about possible problems with the file(s)
5184 being examined. If used on its own then all of the contents of the
5185 file(s) will be examined. If used with one of the dumping options
5186 then the warning messages will only be produced for the things being
5187 displayed.
5188
5189 @item -x <number or name>
5190 @itemx --hex-dump=<number or name>
5191 Displays the contents of the indicated section as a hexadecimal bytes.
5192 A number identifies a particular section by index in the section table;
5193 any other string identifies all sections with that name in the object file.
5194
5195 @item -R <number or name>
5196 @itemx --relocated-dump=<number or name>
5197 Displays the contents of the indicated section as a hexadecimal
5198 bytes. A number identifies a particular section by index in the
5199 section table; any other string identifies all sections with that name
5200 in the object file. The contents of the section will be relocated
5201 before they are displayed.
5202
5203 @item -p <number or name>
5204 @itemx --string-dump=<number or name>
5205 Displays the contents of the indicated section as printable strings.
5206 A number identifies a particular section by index in the section table;
5207 any other string identifies all sections with that name in the object file.
5208
5209 @item -z
5210 @itemx --decompress
5211 Requests that the section(s) being dumped by @option{x}, @option{R} or
5212 @option{p} options are decompressed before being displayed. If the
5213 section(s) are not compressed then they are displayed as is.
5214
5215 @item -c
5216 @itemx --archive-index
5217 @cindex Archive file symbol index information
5218 Displays the file symbol index information contained in the header part
5219 of binary archives. Performs the same function as the @option{t}
5220 command to @command{ar}, but without using the BFD library. @xref{ar}.
5221
5222 @item -w[lLiaprmfFsOoRtUuTgAckK]
5223 @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]
5224 @include debug.options.texi
5225
5226 @item -P
5227 @itemx --process-links
5228 Display the contents of non-debug sections found in separate debuginfo
5229 files that are linked to the main file. This option automatically
5230 implies the @option{-wK} option, and only sections requested by other
5231 command line options will be displayed.
5232
5233 @include ctf.options.texi
5234 @item --ctf-symbols=@var{section}
5235 @item --ctf-strings=@var{section}
5236 Specify the name of another section from which the CTF file can inherit
5237 strings and symbols. By default, the @code{.symtab} and its linked
5238 string table are used.
5239
5240 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
5241 other must be specified as well.
5242
5243 @item -I
5244 @itemx --histogram
5245 Display a histogram of bucket list lengths when displaying the contents
5246 of the symbol tables.
5247
5248 @item -v
5249 @itemx --version
5250 Display the version number of readelf.
5251
5252 @item -W
5253 @itemx --wide
5254 Don't break output lines to fit into 80 columns. By default
5255 @command{readelf} breaks section header and segment listing lines for
5256 64-bit ELF files, so that they fit into 80 columns. This option causes
5257 @command{readelf} to print each section header resp. each segment one a
5258 single line, which is far more readable on terminals wider than 80 columns.
5259
5260 @item -T
5261 @itemx --silent-truncation
5262 Normally when readelf is displaying a symbol name, and it has to
5263 truncate the name to fit into an 80 column display, it will add a
5264 suffix of @code{[...]} to the name. This command line option
5265 disables this behaviour, allowing 5 more characters of the name to be
5266 displayed and restoring the old behaviour of readelf (prior to release
5267 2.35).
5268
5269 @item -H
5270 @itemx --help
5271 Display the command-line options understood by @command{readelf}.
5272
5273 @end table
5274
5275 @c man end
5276
5277 @ignore
5278 @c man begin SEEALSO readelf
5279 objdump(1), and the Info entries for @file{binutils}.
5280 @c man end
5281 @end ignore
5282
5283 @node elfedit
5284 @chapter elfedit
5285
5286 @cindex Update ELF header
5287 @kindex elfedit
5288
5289 @c man title elfedit update ELF header and program property of ELF files
5290
5291 @smallexample
5292 @c man begin SYNOPSIS elfedit
5293 elfedit [@option{--input-mach=}@var{machine}]
5294 [@option{--input-type=}@var{type}]
5295 [@option{--input-osabi=}@var{osabi}]
5296 [@option{--input-abiversion=}@var{version}]
5297 @option{--output-mach=}@var{machine}
5298 @option{--output-type=}@var{type}
5299 @option{--output-osabi=}@var{osabi}
5300 @option{--output-abiversion=}@var{version}
5301 @option{--enable-x86-feature=}@var{feature}
5302 @option{--disable-x86-feature=}@var{feature}
5303 [@option{-v}|@option{--version}]
5304 [@option{-h}|@option{--help}]
5305 @var{elffile}@dots{}
5306 @c man end
5307 @end smallexample
5308
5309 @c man begin DESCRIPTION elfedit
5310
5311 @command{elfedit} updates the ELF header and program property of ELF
5312 files which have the matching ELF machine and file types. The options
5313 control how and which fields in the ELF header and program property
5314 should be updated.
5315
5316 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
5317 64-bit ELF files are supported, as are archives containing ELF files.
5318 @c man end
5319
5320 @c man begin OPTIONS elfedit
5321
5322 The long and short forms of options, shown here as alternatives, are
5323 equivalent. At least one of the @option{--output-mach},
5324 @option{--output-type}, @option{--output-osabi},
5325 @option{--output-abiversion},
5326 @option{--enable-x86-feature} and @option{--disable-x86-feature}
5327 options must be given.
5328
5329 @table @env
5330
5331 @item --input-mach=@var{machine}
5332 Set the matching input ELF machine type to @var{machine}. If
5333 @option{--input-mach} isn't specified, it will match any ELF
5334 machine types.
5335
5336 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5337 @var{K1OM} and @var{x86-64}.
5338
5339 @item --output-mach=@var{machine}
5340 Change the ELF machine type in the ELF header to @var{machine}. The
5341 supported ELF machine types are the same as @option{--input-mach}.
5342
5343 @item --input-type=@var{type}
5344 Set the matching input ELF file type to @var{type}. If
5345 @option{--input-type} isn't specified, it will match any ELF file types.
5346
5347 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5348
5349 @item --output-type=@var{type}
5350 Change the ELF file type in the ELF header to @var{type}. The
5351 supported ELF types are the same as @option{--input-type}.
5352
5353 @item --input-osabi=@var{osabi}
5354 Set the matching input ELF file OSABI to @var{osabi}. If
5355 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5356
5357 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5358 @var{GNU}, @var{Linux} (alias for @var{GNU}),
5359 @var{Solaris}, @var{AIX}, @var{Irix},
5360 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5361 @var{NSK}, @var{AROS} and @var{FenixOS}.
5362
5363 @item --output-osabi=@var{osabi}
5364 Change the ELF OSABI in the ELF header to @var{osabi}. The
5365 supported ELF OSABI are the same as @option{--input-osabi}.
5366
5367 @item --input-abiversion=@var{version}
5368 Set the matching input ELF file ABIVERSION to @var{version}.
5369 @var{version} must be between 0 and 255. If @option{--input-abiversion}
5370 isn't specified, it will match any ELF ABIVERSIONs.
5371
5372 @item --output-abiversion=@var{version}
5373 Change the ELF ABIVERSION in the ELF header to @var{version}.
5374 @var{version} must be between 0 and 255.
5375
5376 @item --enable-x86-feature=@var{feature}
5377 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5378 ELF files with machine types of @var{i386} or @var{x86-64}. The
5379 supported features are, @var{ibt}, @var{shstk}, @var{lam_u48} and
5380 @var{lam_u57}.
5381
5382 @item --disable-x86-feature=@var{feature}
5383 Clear the @var{feature} bit in program property in @var{exec} or
5384 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5385 The supported features are the same as @option{--enable-x86-feature}.
5386
5387 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5388 are available only on hosts with @samp{mmap} support.
5389
5390 @item -v
5391 @itemx --version
5392 Display the version number of @command{elfedit}.
5393
5394 @item -h
5395 @itemx --help
5396 Display the command-line options understood by @command{elfedit}.
5397
5398 @end table
5399
5400 @c man end
5401
5402 @ignore
5403 @c man begin SEEALSO elfedit
5404 readelf(1), and the Info entries for @file{binutils}.
5405 @c man end
5406 @end ignore
5407
5408 @node Common Options
5409 @chapter Common Options
5410
5411 The following command-line options are supported by all of the
5412 programs described in this manual.
5413
5414 @c man begin OPTIONS
5415 @table @env
5416 @include at-file.texi
5417 @c man end
5418
5419 @item --help
5420 Display the command-line options supported by the program.
5421
5422 @item --version
5423 Display the version number of the program.
5424
5425 @c man begin OPTIONS
5426 @end table
5427 @c man end
5428
5429 @node Selecting the Target System
5430 @chapter Selecting the Target System
5431
5432 You can specify two aspects of the target system to the @sc{gnu}
5433 binary file utilities, each in several ways:
5434
5435 @itemize @bullet
5436 @item
5437 the target
5438
5439 @item
5440 the architecture
5441 @end itemize
5442
5443 In the following summaries, the lists of ways to specify values are in
5444 order of decreasing precedence. The ways listed first override those
5445 listed later.
5446
5447 The commands to list valid values only list the values for which the
5448 programs you are running were configured. If they were configured with
5449 @option{--enable-targets=all}, the commands list most of the available
5450 values, but a few are left out; not all targets can be configured in at
5451 once because some of them can only be configured @dfn{native} (on hosts
5452 with the same type as the target system).
5453
5454 @menu
5455 * Target Selection::
5456 * Architecture Selection::
5457 @end menu
5458
5459 @node Target Selection
5460 @section Target Selection
5461
5462 A @dfn{target} is an object file format. A given target may be
5463 supported for multiple architectures (@pxref{Architecture Selection}).
5464 A target selection may also have variations for different operating
5465 systems or architectures.
5466
5467 The command to list valid target values is @samp{objdump -i}
5468 (the first column of output contains the relevant information).
5469
5470 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5471 @samp{a.out-sunos-big}.
5472
5473 You can also specify a target using a configuration triplet. This is
5474 the same sort of name that is passed to @file{configure} to specify a
5475 target. When you use a configuration triplet as an argument, it must be
5476 fully canonicalized. You can see the canonical version of a triplet by
5477 running the shell script @file{config.sub} which is included with the
5478 sources.
5479
5480 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5481 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5482
5483 @subheading @command{objdump} Target
5484
5485 Ways to specify:
5486
5487 @enumerate
5488 @item
5489 command-line option: @option{-b} or @option{--target}
5490
5491 @item
5492 environment variable @code{GNUTARGET}
5493
5494 @item
5495 deduced from the input file
5496 @end enumerate
5497
5498 @subheading @command{objcopy} and @command{strip} Input Target
5499
5500 Ways to specify:
5501
5502 @enumerate
5503 @item
5504 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5505
5506 @item
5507 environment variable @code{GNUTARGET}
5508
5509 @item
5510 deduced from the input file
5511 @end enumerate
5512
5513 @subheading @command{objcopy} and @command{strip} Output Target
5514
5515 Ways to specify:
5516
5517 @enumerate
5518 @item
5519 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5520
5521 @item
5522 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5523
5524 @item
5525 environment variable @code{GNUTARGET}
5526
5527 @item
5528 deduced from the input file
5529 @end enumerate
5530
5531 @subheading @command{nm}, @command{size}, and @command{strings} Target
5532
5533 Ways to specify:
5534
5535 @enumerate
5536 @item
5537 command-line option: @option{--target}
5538
5539 @item
5540 environment variable @code{GNUTARGET}
5541
5542 @item
5543 deduced from the input file
5544 @end enumerate
5545
5546 @node Architecture Selection
5547 @section Architecture Selection
5548
5549 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5550 to run. Its name may contain a colon, separating the name of the
5551 processor family from the name of the particular @sc{cpu}.
5552
5553 The command to list valid architecture values is @samp{objdump -i} (the
5554 second column contains the relevant information).
5555
5556 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5557
5558 @subheading @command{objdump} Architecture
5559
5560 Ways to specify:
5561
5562 @enumerate
5563 @item
5564 command-line option: @option{-m} or @option{--architecture}
5565
5566 @item
5567 deduced from the input file
5568 @end enumerate
5569
5570 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5571
5572 Ways to specify:
5573
5574 @enumerate
5575 @item
5576 deduced from the input file
5577 @end enumerate
5578
5579 @node debuginfod
5580 @chapter debuginfod
5581 @cindex separate debug files
5582
5583 debuginfod is a web service that indexes ELF/DWARF debugging resources
5584 by build-id and serves them over HTTP. For more information see:
5585 @emph{https://sourceware.org/elfutils/Debuginfod.html}
5586
5587 Binutils can be built with the debuginfod client library
5588 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5589 This option is enabled by default if @code{libdebuginfod} is installed
5590 and found at configure time. This allows @command{objdump} and
5591 @command{readelf} to automatically query debuginfod servers for
5592 separate debug files when the files are otherwise not found.
5593
5594 debuginfod is packaged with elfutils, starting with version 0.178.
5595 You can get the latest version from `https://sourceware.org/elfutils/'.
5596
5597 The DWARF info dumping tools (@command{readelf} and @command{objdump})
5598 have options to control when they should access the debuginfod
5599 servers. By default this access is enabled.
5600
5601 @node Reporting Bugs
5602 @chapter Reporting Bugs
5603 @cindex bugs
5604 @cindex reporting bugs
5605
5606 Your bug reports play an essential role in making the binary utilities
5607 reliable.
5608
5609 Reporting a bug may help you by bringing a solution to your problem, or
5610 it may not. But in any case the principal function of a bug report is
5611 to help the entire community by making the next version of the binary
5612 utilities work better. Bug reports are your contribution to their
5613 maintenance.
5614
5615 In order for a bug report to serve its purpose, you must include the
5616 information that enables us to fix the bug.
5617
5618 @menu
5619 * Bug Criteria:: Have you found a bug?
5620 * Bug Reporting:: How to report bugs
5621 @end menu
5622
5623 @node Bug Criteria
5624 @section Have You Found a Bug?
5625 @cindex bug criteria
5626
5627 If you are not sure whether you have found a bug, here are some guidelines:
5628
5629 @itemize @bullet
5630 @cindex fatal signal
5631 @cindex crash
5632 @item
5633 If a binary utility gets a fatal signal, for any input whatever, that is
5634 a bug. Reliable utilities never crash.
5635
5636 @cindex error on valid input
5637 @item
5638 If a binary utility produces an error message for valid input, that is a
5639 bug.
5640
5641 @item
5642 If you are an experienced user of binary utilities, your suggestions for
5643 improvement are welcome in any case.
5644 @end itemize
5645
5646 @node Bug Reporting
5647 @section How to Report Bugs
5648 @cindex bug reports
5649 @cindex bugs, reporting
5650
5651 A number of companies and individuals offer support for @sc{gnu}
5652 products. If you obtained the binary utilities from a support
5653 organization, we recommend you contact that organization first.
5654
5655 You can find contact information for many support companies and
5656 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5657 distribution.
5658
5659 @ifset BUGURL
5660 In any event, we also recommend that you send bug reports for the binary
5661 utilities to @value{BUGURL}.
5662 @end ifset
5663
5664 The fundamental principle of reporting bugs usefully is this:
5665 @strong{report all the facts}. If you are not sure whether to state a
5666 fact or leave it out, state it!
5667
5668 Often people omit facts because they think they know what causes the
5669 problem and assume that some details do not matter. Thus, you might
5670 assume that the name of a file you use in an example does not matter.
5671 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5672 a stray memory reference which happens to fetch from the location where
5673 that pathname is stored in memory; perhaps, if the pathname were
5674 different, the contents of that location would fool the utility into
5675 doing the right thing despite the bug. Play it safe and give a
5676 specific, complete example. That is the easiest thing for you to do,
5677 and the most helpful.
5678
5679 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5680 it is new to us. Therefore, always write your bug reports on the assumption
5681 that the bug has not been reported previously.
5682
5683 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5684 bell?'' This cannot help us fix a bug, so it is basically useless. We
5685 respond by asking for enough details to enable us to investigate.
5686 You might as well expedite matters by sending them to begin with.
5687
5688 To enable us to fix the bug, you should include all these things:
5689
5690 @itemize @bullet
5691 @item
5692 The version of the utility. Each utility announces it if you start it
5693 with the @option{--version} argument.
5694
5695 Without this, we will not know whether there is any point in looking for
5696 the bug in the current version of the binary utilities.
5697
5698 @item
5699 Any patches you may have applied to the source, including any patches
5700 made to the @code{BFD} library.
5701
5702 @item
5703 The type of machine you are using, and the operating system name and
5704 version number.
5705
5706 @item
5707 What compiler (and its version) was used to compile the utilities---e.g.
5708 ``@code{gcc-2.7}''.
5709
5710 @item
5711 The command arguments you gave the utility to observe the bug. To
5712 guarantee you will not omit something important, list them all. A copy
5713 of the Makefile (or the output from make) is sufficient.
5714
5715 If we were to try to guess the arguments, we would probably guess wrong
5716 and then we might not encounter the bug.
5717
5718 @item
5719 A complete input file, or set of input files, that will reproduce the
5720 bug. If the utility is reading an object file or files, then it is
5721 generally most helpful to send the actual object files.
5722
5723 If the source files were produced exclusively using @sc{gnu} programs
5724 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5725 may be OK to send the source files rather than the object files. In
5726 this case, be sure to say exactly what version of @command{gcc}, or
5727 whatever, was used to produce the object files. Also say how
5728 @command{gcc}, or whatever, was configured.
5729
5730 @item
5731 A description of what behavior you observe that you believe is
5732 incorrect. For example, ``It gets a fatal signal.''
5733
5734 Of course, if the bug is that the utility gets a fatal signal, then we
5735 will certainly notice it. But if the bug is incorrect output, we might
5736 not notice unless it is glaringly wrong. You might as well not give us
5737 a chance to make a mistake.
5738
5739 Even if the problem you experience is a fatal signal, you should still
5740 say so explicitly. Suppose something strange is going on, such as your
5741 copy of the utility is out of sync, or you have encountered a bug in
5742 the C library on your system. (This has happened!) Your copy might
5743 crash and ours would not. If you told us to expect a crash, then when
5744 ours fails to crash, we would know that the bug was not happening for
5745 us. If you had not told us to expect a crash, then we would not be able
5746 to draw any conclusion from our observations.
5747
5748 @item
5749 If you wish to suggest changes to the source, send us context diffs, as
5750 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5751 option. Always send diffs from the old file to the new file. If you
5752 wish to discuss something in the @command{ld} source, refer to it by
5753 context, not by line number.
5754
5755 The line numbers in our development sources will not match those in your
5756 sources. Your line numbers would convey no useful information to us.
5757 @end itemize
5758
5759 Here are some things that are not necessary:
5760
5761 @itemize @bullet
5762 @item
5763 A description of the envelope of the bug.
5764
5765 Often people who encounter a bug spend a lot of time investigating
5766 which changes to the input file will make the bug go away and which
5767 changes will not affect it.
5768
5769 This is often time consuming and not very useful, because the way we
5770 will find the bug is by running a single example under the debugger
5771 with breakpoints, not by pure deduction from a series of examples.
5772 We recommend that you save your time for something else.
5773
5774 Of course, if you can find a simpler example to report @emph{instead}
5775 of the original one, that is a convenience for us. Errors in the
5776 output will be easier to spot, running under the debugger will take
5777 less time, and so on.
5778
5779 However, simplification is not vital; if you do not want to do this,
5780 report the bug anyway and send us the entire test case you used.
5781
5782 @item
5783 A patch for the bug.
5784
5785 A patch for the bug does help us if it is a good one. But do not omit
5786 the necessary information, such as the test case, on the assumption that
5787 a patch is all we need. We might see problems with your patch and decide
5788 to fix the problem another way, or we might not understand it at all.
5789
5790 Sometimes with programs as complicated as the binary utilities it is
5791 very hard to construct an example that will make the program follow a
5792 certain path through the code. If you do not send us the example, we
5793 will not be able to construct one, so we will not be able to verify that
5794 the bug is fixed.
5795
5796 And if we cannot understand what bug you are trying to fix, or why your
5797 patch should be an improvement, we will not install it. A test case will
5798 help us to understand.
5799
5800 @item
5801 A guess about what the bug is or what it depends on.
5802
5803 Such guesses are usually wrong. Even we cannot guess right about such
5804 things without first using the debugger to find the facts.
5805 @end itemize
5806
5807 @node GNU Free Documentation License
5808 @appendix GNU Free Documentation License
5809
5810 @include fdl.texi
5811
5812 @node Binutils Index
5813 @unnumbered Binutils Index
5814
5815 @printindex cp
5816
5817 @bye