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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{} 1991-2023 Free Software Foundation, Inc.
14
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
21
22 @c man end
23 @end copying
24
25 @dircategory Software development
26 @direntry
27 * Binutils: (binutils). The GNU binary utilities.
28 @end direntry
29
30 @dircategory Individual utilities
31 @direntry
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nm: (binutils)nm. List symbols from object files.
38 * objcopy: (binutils)objcopy. Copy and translate object files.
39 * objdump: (binutils)objdump. Display information from object files.
40 * ranlib: (binutils)ranlib. Generate index to archive contents.
41 * readelf: (binutils)readelf. Display the contents of ELF format files.
42 * size: (binutils)size. List section sizes and total size.
43 * strings: (binutils)strings. List printable strings from files.
44 * strip: (binutils)strip. Discard symbols.
45 * elfedit: (binutils)elfedit. Update ELF header and property of ELF files.
46 * windmc: (binutils)windmc. Generator for Windows message resources.
47 * windres: (binutils)windres. Manipulate Windows resources.
48 @end direntry
49
50 @titlepage
51 @title The @sc{gnu} Binary Utilities
52 @ifset VERSION_PACKAGE
53 @subtitle @value{VERSION_PACKAGE}
54 @end ifset
55 @subtitle Version @value{VERSION}
56 @sp 1
57 @subtitle @value{UPDATED}
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
61 @page
62
63 @tex
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 Texinfo \texinfoversion\par }
66 @end tex
67
68 @vskip 0pt plus 1filll
69 @insertcopying
70 @end titlepage
71 @contents
72
73 @node Top
74 @top Introduction
75
76 @cindex version
77 This brief manual contains documentation for the @sc{gnu} binary
78 utilities
79 @ifset VERSION_PACKAGE
80 @value{VERSION_PACKAGE}
81 @end ifset
82 version @value{VERSION}:
83
84 @iftex
85 @table @code
86 @item ar
87 Create, modify, and extract from archives
88
89 @item nm
90 List symbols from object files
91
92 @item objcopy
93 Copy and translate object files
94
95 @item objdump
96 Display information from object files
97
98 @item ranlib
99 Generate index to archive contents
100
101 @item readelf
102 Display the contents of ELF format files.
103
104 @item size
105 List file section sizes and total size
106
107 @item strings
108 List printable strings from files
109
110 @item strip
111 Discard symbols
112
113 @item elfedit
114 Update the ELF header and program property of ELF files.
115
116 @item c++filt
117 Demangle encoded C++ symbols (on MS-DOS, this program is named
118 @code{cxxfilt})
119
120 @item addr2line
121 Convert addresses or symbol+offset into file names and line numbers
122
123 @item windres
124 Manipulate Windows resources
125
126 @item windmc
127 Generator for Windows message resources
128
129 @item dlltool
130 Create the files needed to build and use Dynamic Link Libraries
131 @end table
132 @end iftex
133
134 This document is distributed under the terms of the GNU Free
135 Documentation License version 1.3. A copy of the license is included
136 in the section entitled ``GNU Free Documentation License''.
137
138 @menu
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * size:: List section sizes and total size
145 * strings:: List printable strings from files
146 * strip:: Discard symbols
147 * c++filt:: Filter to demangle encoded C++ symbols
148 * cxxfilt: c++filt. MS-DOS name for c++filt
149 * addr2line:: Convert addresses or symbol+offset to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update ELF header and property of ELF files
155 * Common Options:: Command-line options for all utilities
156 * Selecting the Target System:: How these utilities determine the target
157 * debuginfod:: Using binutils with debuginfod
158 * Reporting Bugs:: Reporting Bugs
159 * GNU Free Documentation License:: GNU Free Documentation License
160 * Binutils Index:: Binutils Index
161 @end menu
162
163 @node ar
164 @chapter ar
165
166 @kindex ar
167 @cindex archives
168 @cindex collections of files
169
170 @c man title ar create, modify, and extract from archives
171
172 @smallexample
173 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
174 ar -M [ <mri-script ]
175 @end smallexample
176
177 @c man begin DESCRIPTION ar
178
179 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
180 archives. An @dfn{archive} is a single file holding a collection of
181 other files in a structure that makes it possible to retrieve
182 the original individual files (called @dfn{members} of the archive).
183
184 The original files' contents, mode (permissions), timestamp, owner, and
185 group are preserved in the archive, and can be restored on
186 extraction.
187
188 @cindex name length
189 @sc{gnu} @command{ar} can maintain archives whose members have names of any
190 length; however, depending on how @command{ar} is configured on your
191 system, a limit on member-name length may be imposed for compatibility
192 with archive formats maintained with other tools. If it exists, the
193 limit is often 15 characters (typical of formats related to a.out) or 16
194 characters (typical of formats related to coff).
195
196 @cindex libraries
197 @command{ar} is considered a binary utility because archives of this sort
198 are most often used as @dfn{libraries} holding commonly needed
199 subroutines. Since libraries often will depend on other libraries,
200 @command{ar} can also record the dependencies of a library when the
201 @option{--record-libdeps} option is specified.
202
203 @cindex symbol index
204 @command{ar} creates an index to the symbols defined in relocatable
205 object modules in the archive when you specify the modifier @samp{s}.
206 Once created, this index is updated in the archive whenever @command{ar}
207 makes a change to its contents (save for the @samp{q} update operation).
208 An archive with such an index speeds up linking to the library, and
209 allows routines in the library to call each other without regard to
210 their placement in the archive.
211
212 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
213 table. If an archive lacks the table, another form of @command{ar} called
214 @command{ranlib} can be used to add just the table.
215
216 @cindex thin archives
217 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
218 which contains a symbol index and references to the original copies
219 of the member files of the archive. This is useful for building
220 libraries for use within a local build tree, where the relocatable
221 objects are expected to remain available, and copying the contents of
222 each object would only waste time and space.
223
224 An archive can either be @emph{thin} or it can be normal. It cannot
225 be both at the same time. Once an archive is created its format
226 cannot be changed without first deleting it and then creating a new
227 archive in its place.
228
229 Thin archives are also @emph{flattened}, so that adding one thin
230 archive to another thin archive does not nest it, as would happen with
231 a normal archive. Instead the elements of the first archive are added
232 individually to the second archive.
233
234 The paths to the elements of the archive are stored relative to the
235 archive itself.
236
237 @cindex compatibility, @command{ar}
238 @cindex @command{ar} compatibility
239 @sc{gnu} @command{ar} is designed to be compatible with two different
240 facilities. You can control its activity using command-line options,
241 like the different varieties of @command{ar} on Unix systems; or, if you
242 specify the single command-line option @option{-M}, you can control it
243 with a script supplied via standard input, like the MRI ``librarian''
244 program.
245
246 @c man end
247
248 @menu
249 * ar cmdline:: Controlling @command{ar} on the command line
250 * ar scripts:: Controlling @command{ar} with a script
251 @end menu
252
253 @page
254 @node ar cmdline
255 @section Controlling @command{ar} on the Command Line
256
257 @smallexample
258 @c man begin SYNOPSIS ar
259 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@option{--thin}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
260 @c man end
261 @end smallexample
262
263 @cindex Unix compatibility, @command{ar}
264 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
265 arguments to execute: one keyletter specifying the @emph{operation}
266 (optionally accompanied by other keyletters specifying
267 @emph{modifiers}), and the archive name to act on.
268
269 Most operations can also accept further @var{member} arguments,
270 specifying particular files to operate on.
271
272 @c man begin OPTIONS ar
273
274 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
275 flags @var{mod} in any order, within the first command-line argument.
276
277 If you wish, you may begin the first command-line argument with a
278 dash.
279
280 @cindex operations on archive
281 The @var{p} keyletter specifies what operation to execute; it may be
282 any of the following, but you must specify only one of them:
283
284 @table @samp
285 @item d
286 @cindex deleting from archive
287 @emph{Delete} modules from the archive. Specify the names of modules to
288 be deleted as @var{member}@dots{}; the archive is untouched if you
289 specify no files to delete.
290
291 If you specify the @samp{v} modifier, @command{ar} lists each module
292 as it is deleted.
293
294 @item m
295 @cindex moving in archive
296 Use this operation to @emph{move} members in an archive.
297
298 The ordering of members in an archive can make a difference in how
299 programs are linked using the library, if a symbol is defined in more
300 than one member.
301
302 If no modifiers are used with @code{m}, any members you name in the
303 @var{member} arguments are moved to the @emph{end} of the archive;
304 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
305 specified place instead.
306
307 @item p
308 @cindex printing from archive
309 @emph{Print} the specified members of the archive, to the standard
310 output file. If the @samp{v} modifier is specified, show the member
311 name before copying its contents to standard output.
312
313 If you specify no @var{member} arguments, all the files in the archive are
314 printed.
315
316 @item q
317 @cindex quick append to archive
318 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
319 @var{archive}, without checking for replacement.
320
321 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
322 operation; new members are always placed at the end of the archive.
323
324 The modifier @samp{v} makes @command{ar} list each file as it is appended.
325
326 Since the point of this operation is speed, implementations of
327 @command{ar} have the option of not updating the archive's symbol
328 table if one exists. Too many different systems however assume that
329 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
330 rebuild the table even with a quick append.
331
332 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
333 synonym for @samp{r} - replacing already existing files in the
334 archive and appending new ones at the end.
335
336 @item r
337 @cindex replacement in archive
338 Insert the files @var{member}@dots{} into @var{archive} (with
339 @emph{replacement}). This operation differs from @samp{q} in that any
340 previously existing members are deleted if their names match those being
341 added.
342
343 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
344 displays an error message, and leaves undisturbed any existing members
345 of the archive matching that name.
346
347 By default, new members are added at the end of the file; but you may
348 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
349 placement relative to some existing member.
350
351 The modifier @samp{v} used with this operation elicits a line of
352 output for each file inserted, along with one of the letters @samp{a} or
353 @samp{r} to indicate whether the file was appended (no old member
354 deleted) or replaced.
355
356 @item s
357 @cindex ranlib
358 Add an index to the archive, or update it if it already exists. Note
359 this command is an exception to the rule that there can only be one
360 command letter, as it is possible to use it as either a command or a
361 modifier. In either case it does the same thing.
362
363 @item t
364 @cindex contents of archive
365 Display a @emph{table} listing the contents of @var{archive}, or those
366 of the files listed in @var{member}@dots{} that are present in the
367 archive. Normally only the member name is shown, but if the modifier
368 @samp{O} is specified, then the corresponding offset of the member is also
369 displayed. Finally, in order to see the modes (permissions), timestamp,
370 owner, group, and size the @samp{v} modifier should be included.
371
372 If you do not specify a @var{member}, all files in the archive
373 are listed.
374
375 @cindex repeated names in archive
376 @cindex name duplication in archive
377 If there is more than one file with the same name (say, @samp{fie}) in
378 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
379 first instance; to see them all, you must ask for a complete
380 listing---in our example, @samp{ar t b.a}.
381 @c WRS only; per Gumby, this is implementation-dependent, and in a more
382 @c recent case in fact works the other way.
383
384 @item x
385 @cindex extract from archive
386 @emph{Extract} members (named @var{member}) from the archive. You can
387 use the @samp{v} modifier with this operation, to request that
388 @command{ar} list each name as it extracts it.
389
390 If you do not specify a @var{member}, all files in the archive
391 are extracted.
392
393 Files cannot be extracted from a thin archive, and there are
394 restrictions on extracting from archives created with @option{P}: The
395 paths must not be absolute, may not contain @code{..}, and any
396 subdirectories in the paths must exist. If it is desired to avoid
397 these restrictions then used the @option{--output} option to specify
398 an output directory.
399 @end table
400
401 A number of modifiers (@var{mod}) may immediately follow the @var{p}
402 keyletter, to specify variations on an operation's behavior:
403
404 @table @samp
405 @item a
406 @cindex relative placement in archive
407 Add new files @emph{after} an existing member of the
408 archive. If you use the modifier @samp{a}, the name of an existing archive
409 member must be present as the @var{relpos} argument, before the
410 @var{archive} specification.
411
412 @item b
413 Add new files @emph{before} an existing member of the
414 archive. If you use the modifier @samp{b}, the name of an existing archive
415 member must be present as the @var{relpos} argument, before the
416 @var{archive} specification. (same as @samp{i}).
417
418 @item c
419 @cindex creating archives
420 @emph{Create} the archive. The specified @var{archive} is always
421 created if it did not exist, when you request an update. But a warning is
422 issued unless you specify in advance that you expect to create it, by
423 using this modifier.
424
425 @item D
426 @cindex deterministic archives
427 @kindex --enable-deterministic-archives
428 Operate in @emph{deterministic} mode. When adding files and the archive
429 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
430 for all files. When this option is used, if @command{ar} is used with
431 identical options and identical input files, multiple runs will create
432 identical output files regardless of the input files' owners, groups,
433 file modes, or modification times.
434
435 If @file{binutils} was configured with
436 @option{--enable-deterministic-archives}, then this mode is on by default.
437 It can be disabled with the @samp{U} modifier, below.
438
439 @item f
440 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
441 names of any length. This will cause it to create archives which are
442 not compatible with the native @command{ar} program on some systems. If
443 this is a concern, the @samp{f} modifier may be used to truncate file
444 names when putting them in the archive.
445
446 @item i
447 Insert new files @emph{before} an existing member of the
448 archive. If you use the modifier @samp{i}, the name of an existing archive
449 member must be present as the @var{relpos} argument, before the
450 @var{archive} specification. (same as @samp{b}).
451
452 @item l
453 @c This modifier was accepted but not used.
454 @c whaffor ar l modifier??? presumably compat; with
455 @c what???---doc@@cygnus.com, 25jan91
456 Specify dependencies of this library. The dependencies must immediately
457 follow this option character, must use the same syntax as the linker
458 command line, and must be specified within a single argument. I.e., if
459 multiple items are needed, they must be quoted to form a single command
460 line argument. For example @samp{L "-L/usr/local/lib -lmydep1 -lmydep2"}
461
462 @item N
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
466
467 @item o
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
472
473 @item O
474 @cindex offsets of files
475 Display member offsets inside the archive. Use together with the @samp{t}
476 option.
477
478 @item P
479 Use the full path name when matching or storing names in the archive.
480 Archives created with full path names are not POSIX compliant, and
481 thus may not work with tools other than up to date @sc{gnu} tools.
482 Modifying such archives with @sc{gnu} @command{ar} without using
483 @option{P} will remove the full path names unless the archive is a
484 thin archive. Note that @option{P} may be useful when adding files to
485 a thin archive since @option{r} without @option{P} ignores the path
486 when choosing which element to replace. Thus
487 @smallexample
488 ar rcST archive.a subdir/file1 subdir/file2 file1
489 @end smallexample
490 will result in the first @code{subdir/file1} being replaced with
491 @code{file1} from the current directory. Adding @option{P} will
492 prevent this replacement.
493
494 @item s
495 @cindex writing archive index
496 Write an object-file index into the archive, or update an existing one,
497 even if no other change is made to the archive. You may use this modifier
498 flag either with any operation, or alone. Running @samp{ar s} on an
499 archive is equivalent to running @samp{ranlib} on it.
500
501 @item S
502 @cindex not writing archive index
503 Do not generate an archive symbol table. This can speed up building a
504 large library in several steps. The resulting archive can not be used
505 with the linker. In order to build a symbol table, you must omit the
506 @samp{S} modifier on the last execution of @samp{ar}, or you must run
507 @samp{ranlib} on the archive.
508
509 @item T
510 Deprecated alias for @option{--thin}. @option{T} is not recommended because in
511 many ar implementations @option{T} has a different meaning, as specified by
512 X/Open System Interface.
513
514 @item u
515 @cindex updating an archive
516 Normally, @samp{ar r}@dots{} inserts all files
517 listed into the archive. If you would like to insert @emph{only} those
518 of the files you list that are newer than existing members of the same
519 names, use this modifier. The @samp{u} modifier is allowed only for the
520 operation @samp{r} (replace). In particular, the combination @samp{qu} is
521 not allowed, since checking the timestamps would lose any speed
522 advantage from the operation @samp{q}.
523
524 @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 a non-data, non-code, non-debug read-only 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{--strip-section-headers}]
1282 [@option{-p}|@option{--preserve-dates}]
1283 [@option{-D}|@option{--enable-deterministic-archives}]
1284 [@option{-U}|@option{--disable-deterministic-archives}]
1285 [@option{--debugging}]
1286 [@option{--gap-fill=}@var{val}]
1287 [@option{--pad-to=}@var{address}]
1288 [@option{--set-start=}@var{val}]
1289 [@option{--adjust-start=}@var{incr}]
1290 [@option{--change-addresses=}@var{incr}]
1291 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1292 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1293 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1294 [@option{--change-warnings}] [@option{--no-change-warnings}]
1295 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1296 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1297 [@option{--add-section} @var{sectionname}=@var{filename}]
1298 [@option{--dump-section} @var{sectionname}=@var{filename}]
1299 [@option{--update-section} @var{sectionname}=@var{filename}]
1300 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1301 [@option{--long-section-names} @{enable,disable,keep@}]
1302 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1303 [@option{--reverse-bytes=}@var{num}]
1304 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1305 [@option{--redefine-sym} @var{old}=@var{new}]
1306 [@option{--redefine-syms=}@var{filename}]
1307 [@option{--weaken}]
1308 [@option{--keep-symbols=}@var{filename}]
1309 [@option{--strip-symbols=}@var{filename}]
1310 [@option{--strip-unneeded-symbols=}@var{filename}]
1311 [@option{--keep-global-symbols=}@var{filename}]
1312 [@option{--localize-symbols=}@var{filename}]
1313 [@option{--weaken-symbols=}@var{filename}]
1314 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1315 [@option{--alt-machine-code=}@var{index}]
1316 [@option{--prefix-symbols=}@var{string}]
1317 [@option{--prefix-sections=}@var{string}]
1318 [@option{--prefix-alloc-sections=}@var{string}]
1319 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1320 [@option{--only-keep-debug}]
1321 [@option{--strip-dwo}]
1322 [@option{--extract-dwo}]
1323 [@option{--extract-symbol}]
1324 [@option{--writable-text}]
1325 [@option{--readonly-text}]
1326 [@option{--pure}]
1327 [@option{--impure}]
1328 [@option{--file-alignment=}@var{num}]
1329 [@option{--heap=}@var{size}]
1330 [@option{--image-base=}@var{address}]
1331 [@option{--section-alignment=}@var{num}]
1332 [@option{--stack=}@var{size}]
1333 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1334 [@option{--compress-debug-sections}]
1335 [@option{--decompress-debug-sections}]
1336 [@option{--elf-stt-common=@var{val}}]
1337 [@option{--merge-notes}]
1338 [@option{--no-merge-notes}]
1339 [@option{--verilog-data-width=@var{val}}]
1340 [@option{-v}|@option{--verbose}]
1341 [@option{-V}|@option{--version}]
1342 [@option{--help}] [@option{--info}]
1343 @var{infile} [@var{outfile}]
1344 @c man end
1345 @end smallexample
1346
1347 @c man begin DESCRIPTION objcopy
1348 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1349 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1350 read and write the object files. It can write the destination object
1351 file in a format different from that of the source object file. The
1352 exact behavior of @command{objcopy} is controlled by command-line options.
1353 Note that @command{objcopy} should be able to copy a fully linked file
1354 between any two formats. However, copying a relocatable object file
1355 between any two formats may not work as expected.
1356
1357 @command{objcopy} creates temporary files to do its translations and
1358 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1359 translation work; it has access to all the formats described in @sc{bfd}
1360 and thus is able to recognize most formats without being told
1361 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1362
1363 @command{objcopy} can be used to generate S-records by using an output
1364 target of @samp{srec} (e.g., use @samp{-O srec}).
1365
1366 @command{objcopy} can be used to generate a raw binary file by using an
1367 output target of @samp{binary} (e.g., use @option{-O binary}). When
1368 @command{objcopy} generates a raw binary file, it will essentially produce
1369 a memory dump of the contents of the input object file. All symbols and
1370 relocation information will be discarded. The memory dump will start at
1371 the load address of the lowest section copied into the output file.
1372
1373 When generating an S-record or a raw binary file, it may be helpful to
1374 use @option{-S} to remove sections containing debugging information. In
1375 some cases @option{-R} will be useful to remove sections which contain
1376 information that is not needed by the binary file.
1377
1378 Note---@command{objcopy} is not able to change the endianness of its input
1379 files. If the input format has an endianness (some formats do not),
1380 @command{objcopy} can only copy the inputs into file formats that have the
1381 same endianness or which have no endianness (e.g., @samp{srec}).
1382 (However, see the @option{--reverse-bytes} option.)
1383
1384 @c man end
1385
1386 @c man begin OPTIONS objcopy
1387
1388 @table @env
1389 @item @var{infile}
1390 @itemx @var{outfile}
1391 The input and output files, respectively.
1392 If you do not specify @var{outfile}, @command{objcopy} creates a
1393 temporary file and destructively renames the result with
1394 the name of @var{infile}.
1395
1396 @item -I @var{bfdname}
1397 @itemx --input-target=@var{bfdname}
1398 Consider the source file's object format to be @var{bfdname}, rather than
1399 attempting to deduce it. @xref{Target Selection}, for more information.
1400
1401 @item -O @var{bfdname}
1402 @itemx --output-target=@var{bfdname}
1403 Write the output file using the object format @var{bfdname}.
1404 @xref{Target Selection}, for more information.
1405
1406 @item -F @var{bfdname}
1407 @itemx --target=@var{bfdname}
1408 Use @var{bfdname} as the object format for both the input and the output
1409 file; i.e., simply transfer data from source to destination with no
1410 translation. @xref{Target Selection}, for more information.
1411
1412 @item -B @var{bfdarch}
1413 @itemx --binary-architecture=@var{bfdarch}
1414 Useful when transforming a architecture-less input file into an object file.
1415 In this case the output architecture can be set to @var{bfdarch}. This
1416 option will be ignored if the input file has a known @var{bfdarch}. You
1417 can access this binary data inside a program by referencing the special
1418 symbols that are created by the conversion process. These symbols are
1419 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1420 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1421 an object file and then access it in your code using these symbols.
1422
1423 @item -j @var{sectionpattern}
1424 @itemx --only-section=@var{sectionpattern}
1425 Copy only the indicated sections from the input file to the output file.
1426 This option may be given more than once. Note that using this option
1427 inappropriately may make the output file unusable. Wildcard
1428 characters are accepted in @var{sectionpattern}.
1429
1430 If the first character of @var{sectionpattern} is the exclamation
1431 point (!) then matching sections will not be copied, even if earlier
1432 use of @option{--only-section} on the same command line would
1433 otherwise copy it. For example:
1434
1435 @smallexample
1436 --only-section=.text.* --only-section=!.text.foo
1437 @end smallexample
1438
1439 will copy all sectinos matching '.text.*' but not the section
1440 '.text.foo'.
1441
1442 @item -R @var{sectionpattern}
1443 @itemx --remove-section=@var{sectionpattern}
1444 Remove any section matching @var{sectionpattern} from the output file.
1445 This option may be given more than once. Note that using this option
1446 inappropriately may make the output file unusable. Wildcard
1447 characters are accepted in @var{sectionpattern}. Using both the
1448 @option{-j} and @option{-R} options together results in undefined
1449 behaviour.
1450
1451 If the first character of @var{sectionpattern} is the exclamation
1452 point (!) then matching sections will not be removed even if an
1453 earlier use of @option{--remove-section} on the same command line
1454 would otherwise remove it. For example:
1455
1456 @smallexample
1457 --remove-section=.text.* --remove-section=!.text.foo
1458 @end smallexample
1459
1460 will remove all sections matching the pattern '.text.*', but will not
1461 remove the section '.text.foo'.
1462
1463 @item --keep-section=@var{sectionpattern}
1464 When removing sections from the output file, keep sections that match
1465 @var{sectionpattern}.
1466
1467 @item --remove-relocations=@var{sectionpattern}
1468 Remove non-dynamic relocations from the output file for any section
1469 matching @var{sectionpattern}. This option may be given more than
1470 once. Note that using this option inappropriately may make the output
1471 file unusable, and attempting to remove a dynamic relocation section
1472 such as @samp{.rela.plt} from an executable or shared library with
1473 @option{--remove-relocations=.plt} will not work. Wildcard characters
1474 are accepted in @var{sectionpattern}.
1475 For example:
1476
1477 @smallexample
1478 --remove-relocations=.text.*
1479 @end smallexample
1480
1481 will remove the relocations for all sections matching the pattern
1482 '.text.*'.
1483
1484 If the first character of @var{sectionpattern} is the exclamation
1485 point (!) then matching sections will not have their relocation
1486 removed even if an earlier use of @option{--remove-relocations} on the
1487 same command line would otherwise cause the relocations to be removed.
1488 For example:
1489
1490 @smallexample
1491 --remove-relocations=.text.* --remove-relocations=!.text.foo
1492 @end smallexample
1493
1494 will remove all relocations for sections matching the pattern
1495 '.text.*', but will not remove relocations for the section
1496 '.text.foo'.
1497
1498 @item --strip-section-headers
1499 Strip section header This option is specific to ELF files.
1500 Implies @option{--strip-all} and @option{--merge-notes}.
1501
1502 @item -S
1503 @itemx --strip-all
1504 Do not copy relocation and symbol information from the source file.
1505 Also deletes debug sections.
1506
1507 @item -g
1508 @itemx --strip-debug
1509 Do not copy debugging symbols or sections from the source file.
1510
1511 @item --strip-unneeded
1512 Remove all symbols that are not needed for relocation processing in
1513 addition to debugging symbols and sections stripped by
1514 @option{--strip-debug}.
1515
1516 @item -K @var{symbolname}
1517 @itemx --keep-symbol=@var{symbolname}
1518 When stripping symbols, keep symbol @var{symbolname} even if it would
1519 normally be stripped. This option may be given more than once.
1520
1521 @item -N @var{symbolname}
1522 @itemx --strip-symbol=@var{symbolname}
1523 Do not copy symbol @var{symbolname} from the source file. This option
1524 may be given more than once.
1525
1526 @item --strip-unneeded-symbol=@var{symbolname}
1527 Do not copy symbol @var{symbolname} from the source file unless it is needed
1528 by a relocation. This option may be given more than once.
1529
1530 @item -G @var{symbolname}
1531 @itemx --keep-global-symbol=@var{symbolname}
1532 Keep only symbol @var{symbolname} global. Make all other symbols local
1533 to the file, so that they are not visible externally. This option may
1534 be given more than once. Note: this option cannot be used in
1535 conjunction with the @option{--globalize-symbol} or
1536 @option{--globalize-symbols} options.
1537
1538 @item --localize-hidden
1539 In an ELF object, mark all symbols that have hidden or internal visibility
1540 as local. This option applies on top of symbol-specific localization options
1541 such as @option{-L}.
1542
1543 @item -L @var{symbolname}
1544 @itemx --localize-symbol=@var{symbolname}
1545 Convert a global or weak symbol called @var{symbolname} into a local
1546 symbol, so that it is not visible externally. This option may be
1547 given more than once. Note - unique symbols are not converted.
1548
1549 @item -W @var{symbolname}
1550 @itemx --weaken-symbol=@var{symbolname}
1551 Make symbol @var{symbolname} weak. This option may be given more than once.
1552
1553 @item --globalize-symbol=@var{symbolname}
1554 Give symbol @var{symbolname} global scoping so that it is visible
1555 outside of the file in which it is defined. This option may be given
1556 more than once. Note: this option cannot be used in conjunction with
1557 the @option{-G} or @option{--keep-global-symbol} options.
1558
1559 @item -w
1560 @itemx --wildcard
1561 Permit regular expressions in @var{symbolname}s used in other command
1562 line options. The question mark (?), asterisk (*), backslash (\) and
1563 square brackets ([]) operators can be used anywhere in the symbol
1564 name. If the first character of the symbol name is the exclamation
1565 point (!) then the sense of the switch is reversed for that symbol.
1566 For example:
1567
1568 @smallexample
1569 -w -W !foo -W fo*
1570 @end smallexample
1571
1572 would cause objcopy to weaken all symbols that start with ``fo''
1573 except for the symbol ``foo''.
1574
1575 @item -x
1576 @itemx --discard-all
1577 Do not copy non-global symbols from the source file.
1578 @c FIXME any reason to prefer "non-global" to "local" here?
1579
1580 @item -X
1581 @itemx --discard-locals
1582 Do not copy compiler-generated local symbols.
1583 (These usually start with @samp{L} or @samp{.}.)
1584
1585 @item -b @var{byte}
1586 @itemx --byte=@var{byte}
1587 If interleaving has been enabled via the @option{--interleave} option
1588 then start the range of bytes to keep at the @var{byte}th byte.
1589 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1590 @var{breadth} is the value given by the @option{--interleave} option.
1591
1592 @item -i [@var{breadth}]
1593 @itemx --interleave[=@var{breadth}]
1594 Only copy a range out of every @var{breadth} bytes. (Header data is
1595 not affected). Select which byte in the range begins the copy with
1596 the @option{--byte} option. Select the width of the range with the
1597 @option{--interleave-width} option.
1598
1599 This option is useful for creating files to program @sc{rom}. It is
1600 typically used with an @code{srec} output target. Note that
1601 @command{objcopy} will complain if you do not specify the
1602 @option{--byte} option as well.
1603
1604 The default interleave breadth is 4, so with @option{--byte} set to 0,
1605 @command{objcopy} would copy the first byte out of every four bytes
1606 from the input to the output.
1607
1608 @item --interleave-width=@var{width}
1609 When used with the @option{--interleave} option, copy @var{width}
1610 bytes at a time. The start of the range of bytes to be copied is set
1611 by the @option{--byte} option, and the extent of the range is set with
1612 the @option{--interleave} option.
1613
1614 The default value for this option is 1. The value of @var{width} plus
1615 the @var{byte} value set by the @option{--byte} option must not exceed
1616 the interleave breadth set by the @option{--interleave} option.
1617
1618 This option can be used to create images for two 16-bit flashes interleaved
1619 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1620 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1621 commands. If the input was '12345678' then the outputs would be
1622 '1256' and '3478' respectively.
1623
1624 @item -p
1625 @itemx --preserve-dates
1626 Set the access and modification dates of the output file to be the same
1627 as those of the input file.
1628
1629 @item -D
1630 @itemx --enable-deterministic-archives
1631 @cindex deterministic archives
1632 @kindex --enable-deterministic-archives
1633 Operate in @emph{deterministic} mode. When copying archive members
1634 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1635 and use consistent file modes for all files.
1636
1637 If @file{binutils} was configured with
1638 @option{--enable-deterministic-archives}, then this mode is on by default.
1639 It can be disabled with the @samp{-U} option, below.
1640
1641 @item -U
1642 @itemx --disable-deterministic-archives
1643 @cindex deterministic archives
1644 @kindex --enable-deterministic-archives
1645 Do @emph{not} operate in @emph{deterministic} mode. This is the
1646 inverse of the @option{-D} option, above: when copying archive members
1647 and writing the archive index, use their actual UID, GID, timestamp,
1648 and file mode values.
1649
1650 This is the default unless @file{binutils} was configured with
1651 @option{--enable-deterministic-archives}.
1652
1653 @item --debugging
1654 Convert debugging information, if possible. This is not the default
1655 because only certain debugging formats are supported, and the
1656 conversion process can be time consuming.
1657
1658 @item --gap-fill @var{val}
1659 Fill gaps between sections with @var{val}. This operation applies to
1660 the @emph{load address} (LMA) of the sections. It is done by increasing
1661 the size of the section with the lower address, and filling in the extra
1662 space created with @var{val}.
1663
1664 @item --pad-to @var{address}
1665 Pad the output file up to the load address @var{address}. This is
1666 done by increasing the size of the last section. The extra space is
1667 filled in with the value specified by @option{--gap-fill} (default zero).
1668
1669 @item --set-start @var{val}
1670 Set the start address (also known as the entry address) of the new
1671 file to @var{val}. Not all object file formats support setting the
1672 start address.
1673
1674 @item --change-start @var{incr}
1675 @itemx --adjust-start @var{incr}
1676 @cindex changing start address
1677 Change the start address (also known as the entry address) by adding
1678 @var{incr}. Not all object file formats support setting the start
1679 address.
1680
1681 @item --change-addresses @var{incr}
1682 @itemx --adjust-vma @var{incr}
1683 @cindex changing object addresses
1684 Change the VMA and LMA addresses of all sections, as well as the start
1685 address, by adding @var{incr}. Some object file formats do not permit
1686 section addresses to be changed arbitrarily. Note that this does not
1687 relocate the sections; if the program expects sections to be loaded at a
1688 certain address, and this option is used to change the sections such
1689 that they are loaded at a different address, the program may fail.
1690
1691 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1692 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1693 @cindex changing section address
1694 Set or change both the VMA address and the LMA address of any section
1695 matching @var{sectionpattern}. If @samp{=} is used, the section
1696 address is set to @var{val}. Otherwise, @var{val} is added to or
1697 subtracted from the section address. See the comments under
1698 @option{--change-addresses}, above. If @var{sectionpattern} does not
1699 match any sections in the input file, a warning will be issued, unless
1700 @option{--no-change-warnings} is used.
1701
1702 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1703 @cindex changing section LMA
1704 Set or change the LMA address of any sections matching
1705 @var{sectionpattern}. The LMA address is the address where the
1706 section will be loaded into memory at program load time. Normally
1707 this is the same as the VMA address, which is the address of the
1708 section at program run time, but on some systems, especially those
1709 where a program is held in ROM, the two can be different. If @samp{=}
1710 is used, the section address is set to @var{val}. Otherwise,
1711 @var{val} is added to or subtracted from the section address. See the
1712 comments under @option{--change-addresses}, above. If
1713 @var{sectionpattern} does not match any sections in the input file, a
1714 warning will be issued, unless @option{--no-change-warnings} is used.
1715
1716 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1717 @cindex changing section VMA
1718 Set or change the VMA address of any section matching
1719 @var{sectionpattern}. The VMA address is the address where the
1720 section will be located once the program has started executing.
1721 Normally this is the same as the LMA address, which is the address
1722 where the section will be loaded into memory, but on some systems,
1723 especially those where a program is held in ROM, the two can be
1724 different. If @samp{=} is used, the section address is set to
1725 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1726 section address. See the comments under @option{--change-addresses},
1727 above. If @var{sectionpattern} does not match any sections in the
1728 input file, a warning will be issued, unless
1729 @option{--no-change-warnings} is used.
1730
1731 @item --change-warnings
1732 @itemx --adjust-warnings
1733 If @option{--change-section-address} or @option{--change-section-lma} or
1734 @option{--change-section-vma} is used, and the section pattern does not
1735 match any sections, issue a warning. This is the default.
1736
1737 @item --no-change-warnings
1738 @itemx --no-adjust-warnings
1739 Do not issue a warning if @option{--change-section-address} or
1740 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1741 if the section pattern does not match any sections.
1742
1743 @item --set-section-flags @var{sectionpattern}=@var{flags}
1744 Set the flags for any sections matching @var{sectionpattern}. The
1745 @var{flags} argument is a comma separated string of flag names. The
1746 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1747 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1748 @samp{exclude}, @samp{share}, @samp{debug}, and @samp{large}.
1749 You can set the @samp{contents} flag for a section which does not have
1750 contents, but it is not meaningful to clear the @samp{contents} flag of a
1751 section which does have contents--just remove the section instead. Not all
1752 flags are meaningful for all object file formats. In particular the
1753 @samp{share} flag is only meaningful for COFF format files and not for ELF
1754 format files. The ELF x86-64 specific flag @samp{large} corresponds to
1755 SHF_X86_64_LARGE.
1756
1757 @item --set-section-alignment @var{sectionpattern}=@var{align}
1758 Set the alignment for any sections matching @var{sectionpattern}.
1759 @var{align} specifies the alignment in bytes and must be a power of
1760 two, i.e. 1, 2, 4, 8@dots{}.
1761
1762 @item --add-section @var{sectionname}=@var{filename}
1763 Add a new section named @var{sectionname} while copying the file. The
1764 contents of the new section are taken from the file @var{filename}. The
1765 size of the section will be the size of the file. This option only
1766 works on file formats which can support sections with arbitrary names.
1767 Note - it may be necessary to use the @option{--set-section-flags}
1768 option to set the attributes of the newly created section.
1769
1770 @item --dump-section @var{sectionname}=@var{filename}
1771 Place the contents of section named @var{sectionname} into the file
1772 @var{filename}, overwriting any contents that may have been there
1773 previously. This option is the inverse of @option{--add-section}.
1774 This option is similar to the @option{--only-section} option except
1775 that it does not create a formatted file, it just dumps the contents
1776 as raw binary data, without applying any relocations. The option can
1777 be specified more than once.
1778
1779 @item --update-section @var{sectionname}=@var{filename}
1780 Replace the existing contents of a section named @var{sectionname}
1781 with the contents of file @var{filename}. The size of the section
1782 will be adjusted to the size of the file. The section flags for
1783 @var{sectionname} will be unchanged. For ELF format files the section
1784 to segment mapping will also remain unchanged, something which is not
1785 possible using @option{--remove-section} followed by
1786 @option{--add-section}. The option can be specified more than once.
1787
1788 Note - it is possible to use @option{--rename-section} and
1789 @option{--update-section} to both update and rename a section from one
1790 command line. In this case, pass the original section name to
1791 @option{--update-section}, and the original and new section names to
1792 @option{--rename-section}.
1793
1794 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1795 Add a new symbol named @var{name} while copying the file. This option may be
1796 specified multiple times. If the @var{section} is given, the symbol will be
1797 associated with and relative to that section, otherwise it will be an ABS
1798 symbol. Specifying an undefined section will result in a fatal error. There
1799 is no check for the value, it will be taken as specified. Symbol flags can
1800 be specified and not all flags will be meaningful for all object file
1801 formats. By default, the symbol will be global. The special flag
1802 'before=@var{othersym}' will insert the new symbol in front of the specified
1803 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1804 symbol table in the order they appear.
1805
1806 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1807 Rename a section from @var{oldname} to @var{newname}, optionally
1808 changing the section's flags to @var{flags} in the process. This has
1809 the advantage over using a linker script to perform the rename in that
1810 the output stays as an object file and does not become a linked
1811 executable. This option accepts the same set of flags as the
1812 @option{--sect-section-flags} option.
1813
1814 This option is particularly helpful when the input format is binary,
1815 since this will always create a section called .data. If for example,
1816 you wanted instead to create a section called .rodata containing binary
1817 data you could use the following command line to achieve it:
1818
1819 @smallexample
1820 objcopy -I binary -O <output_format> -B <architecture> \
1821 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1822 <input_binary_file> <output_object_file>
1823 @end smallexample
1824
1825 @item --long-section-names @{enable,disable,keep@}
1826 Controls the handling of long section names when processing @code{COFF}
1827 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1828 is to preserve long section names if any are present in the input file.
1829 The @samp{enable} and @samp{disable} options forcibly enable or disable
1830 the use of long section names in the output object; when @samp{disable}
1831 is in effect, any long section names in the input object will be truncated.
1832 The @samp{enable} option will only emit long section names if any are
1833 present in the inputs; this is mostly the same as @samp{keep}, but it
1834 is left undefined whether the @samp{enable} option might force the
1835 creation of an empty string table in the output file.
1836
1837 @item --change-leading-char
1838 Some object file formats use special characters at the start of
1839 symbols. The most common such character is underscore, which compilers
1840 often add before every symbol. This option tells @command{objcopy} to
1841 change the leading character of every symbol when it converts between
1842 object file formats. If the object file formats use the same leading
1843 character, this option has no effect. Otherwise, it will add a
1844 character, or remove a character, or change a character, as
1845 appropriate.
1846
1847 @item --remove-leading-char
1848 If the first character of a global symbol is a special symbol leading
1849 character used by the object file format, remove the character. The
1850 most common symbol leading character is underscore. This option will
1851 remove a leading underscore from all global symbols. This can be useful
1852 if you want to link together objects of different file formats with
1853 different conventions for symbol names. This is different from
1854 @option{--change-leading-char} because it always changes the symbol name
1855 when appropriate, regardless of the object file format of the output
1856 file.
1857
1858 @item --reverse-bytes=@var{num}
1859 Reverse the bytes in a section with output contents. A section length must
1860 be evenly divisible by the value given in order for the swap to be able to
1861 take place. Reversing takes place before the interleaving is performed.
1862
1863 This option is used typically in generating ROM images for problematic
1864 target systems. For example, on some target boards, the 32-bit words
1865 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1866 regardless of the CPU byte order. Depending on the programming model, the
1867 endianness of the ROM may need to be modified.
1868
1869 Consider a simple file with a section containing the following eight
1870 bytes: @code{12345678}.
1871
1872 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1873 output file would be ordered @code{21436587}.
1874
1875 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1876 output file would be ordered @code{43218765}.
1877
1878 By using @samp{--reverse-bytes=2} for the above example, followed by
1879 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1880 output file would be ordered @code{34127856}.
1881
1882 @item --srec-len=@var{ival}
1883 Meaningful only for srec output. Set the maximum length of the Srecords
1884 being produced to @var{ival}. This length covers both address, data and
1885 crc fields.
1886
1887 @item --srec-forceS3
1888 Meaningful only for srec output. Avoid generation of S1/S2 records,
1889 creating S3-only record format.
1890
1891 @item --redefine-sym @var{old}=@var{new}
1892 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1893 when one is trying link two things together for which you have no
1894 source, and there are name collisions.
1895
1896 @item --redefine-syms=@var{filename}
1897 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1898 listed in the file @var{filename}. @var{filename} is simply a flat file,
1899 with one symbol pair per line. Line comments may be introduced by the hash
1900 character. This option may be given more than once.
1901
1902 @item --weaken
1903 Change all global symbols in the file to be weak. This can be useful
1904 when building an object which will be linked against other objects using
1905 the @option{-R} option to the linker. This option is only effective when
1906 using an object file format which supports weak symbols.
1907
1908 @item --keep-symbols=@var{filename}
1909 Apply @option{--keep-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-symbols=@var{filename}
1915 Apply @option{--strip-symbol} option to each symbol listed in the file
1916 @var{filename}. @var{filename} is simply a flat file, with one symbol
1917 name per line. Line comments may be introduced by the hash character.
1918 This option may be given more than once.
1919
1920 @item --strip-unneeded-symbols=@var{filename}
1921 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1922 the 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 --keep-global-symbols=@var{filename}
1927 Apply @option{--keep-global-symbol} option to each symbol listed in the
1928 file @var{filename}. @var{filename} is simply a flat file, with one
1929 symbol name per line. Line comments may be introduced by the hash
1930 character. This option may be given more than once.
1931
1932 @item --localize-symbols=@var{filename}
1933 Apply @option{--localize-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.
1937
1938 @item --globalize-symbols=@var{filename}
1939 Apply @option{--globalize-symbol} option to each symbol listed in the file
1940 @var{filename}. @var{filename} is simply a flat file, with one symbol
1941 name per line. Line comments may be introduced by the hash character.
1942 This option may be given more than once. Note: this option cannot be
1943 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1944 options.
1945
1946 @item --weaken-symbols=@var{filename}
1947 Apply @option{--weaken-symbol} option to each symbol listed in the file
1948 @var{filename}. @var{filename} is simply a flat file, with one symbol
1949 name per line. Line comments may be introduced by the hash character.
1950 This option may be given more than once.
1951
1952 @item --alt-machine-code=@var{index}
1953 If the output architecture has alternate machine codes, use the
1954 @var{index}th code instead of the default one. This is useful in case
1955 a machine is assigned an official code and the tool-chain adopts the
1956 new code, but other applications still depend on the original code
1957 being used. For ELF based architectures if the @var{index}
1958 alternative does not exist then the value is treated as an absolute
1959 number to be stored in the e_machine field of the ELF header.
1960
1961 @item --writable-text
1962 Mark the output text as writable. This option isn't meaningful for all
1963 object file formats.
1964
1965 @item --readonly-text
1966 Make the output text write protected. This option isn't meaningful for all
1967 object file formats.
1968
1969 @item --pure
1970 Mark the output file as demand paged. This option isn't meaningful for all
1971 object file formats.
1972
1973 @item --impure
1974 Mark the output file as impure. This option isn't meaningful for all
1975 object file formats.
1976
1977 @item --prefix-symbols=@var{string}
1978 Prefix all symbols in the output file with @var{string}.
1979
1980 @item --prefix-sections=@var{string}
1981 Prefix all section names in the output file with @var{string}.
1982
1983 @item --prefix-alloc-sections=@var{string}
1984 Prefix all the names of all allocated sections in the output file with
1985 @var{string}.
1986
1987 @item --add-gnu-debuglink=@var{path-to-file}
1988 Creates a .gnu_debuglink section which contains a reference to
1989 @var{path-to-file} and adds it to the output file. Note: the file at
1990 @var{path-to-file} must exist. Part of the process of adding the
1991 .gnu_debuglink section involves embedding a checksum of the contents
1992 of the debug info file into the section.
1993
1994 If the debug info file is built in one location but it is going to be
1995 installed at a later time into a different location then do not use
1996 the path to the installed location. The @option{--add-gnu-debuglink}
1997 option will fail because the installed file does not exist yet.
1998 Instead put the debug info file in the current directory and use the
1999 @option{--add-gnu-debuglink} option without any directory components,
2000 like this:
2001
2002 @smallexample
2003 objcopy --add-gnu-debuglink=foo.debug
2004 @end smallexample
2005
2006 At debug time the debugger will attempt to look for the separate debug
2007 info file in a set of known locations. The exact set of these
2008 locations varies depending upon the distribution being used, but it
2009 typically includes:
2010
2011 @table @code
2012
2013 @item * The same directory as the executable.
2014
2015 @item * A sub-directory of the directory containing the executable
2016 called .debug
2017
2018 @item * A global debug directory such as /usr/lib/debug.
2019 @end table
2020
2021 As long as the debug info file has been installed into one of these
2022 locations before the debugger is run everything should work
2023 correctly.
2024
2025 @item --keep-section-symbils
2026 When stripping a file, perhaps with @option{--strip-debug} or
2027 @option{--strip-unneeded}, retain any symbols specifying section names,
2028 which would otherwise get stripped.
2029
2030 @item --keep-file-symbols
2031 When stripping a file, perhaps with @option{--strip-debug} or
2032 @option{--strip-unneeded}, retain any symbols specifying source file names,
2033 which would otherwise get stripped.
2034
2035 @item --only-keep-debug
2036 Strip a file, removing contents of any sections that would not be
2037 stripped by @option{--strip-debug} and leaving the debugging sections
2038 intact. In ELF files, this preserves all note sections in the output.
2039
2040 Note - the section headers of the stripped sections are preserved,
2041 including their sizes, but the contents of the section are discarded.
2042 The section headers are preserved so that other tools can match up the
2043 debuginfo file with the real executable, even if that executable has
2044 been relocated to a different address space.
2045
2046 The intention is that this option will be used in conjunction with
2047 @option{--add-gnu-debuglink} to create a two part executable. One a
2048 stripped binary which will occupy less space in RAM and in a
2049 distribution and the second a debugging information file which is only
2050 needed if debugging abilities are required. The suggested procedure
2051 to create these files is as follows:
2052
2053 @enumerate
2054 @item Link the executable as normal. Assuming that it is called
2055 @code{foo} then...
2056 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2057 create a file containing the debugging info.
2058 @item Run @code{objcopy --strip-debug foo} to create a
2059 stripped executable.
2060 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2061 to add a link to the debugging info into the stripped executable.
2062 @end enumerate
2063
2064 Note---the choice of @code{.dbg} as an extension for the debug info
2065 file is arbitrary. Also the @code{--only-keep-debug} step is
2066 optional. You could instead do this:
2067
2068 @enumerate
2069 @item Link the executable as normal.
2070 @item Copy @code{foo} to @code{foo.full}
2071 @item Run @code{objcopy --strip-debug foo}
2072 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2073 @end enumerate
2074
2075 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2076 full executable. It does not have to be a file created by the
2077 @option{--only-keep-debug} switch.
2078
2079 Note---this switch is only intended for use on fully linked files. It
2080 does not make sense to use it on object files where the debugging
2081 information may be incomplete. Besides the gnu_debuglink feature
2082 currently only supports the presence of one filename containing
2083 debugging information, not multiple filenames on a one-per-object-file
2084 basis.
2085
2086 @item --strip-dwo
2087 Remove the contents of all DWARF .dwo sections, leaving the
2088 remaining debugging sections and all symbols intact.
2089 This option is intended for use by the compiler as part of
2090 the @option{-gsplit-dwarf} option, which splits debug information
2091 between the .o file and a separate .dwo file. The compiler
2092 generates all debug information in the same file, then uses
2093 the @option{--extract-dwo} option to copy the .dwo sections to
2094 the .dwo file, then the @option{--strip-dwo} option to remove
2095 those sections from the original .o file.
2096
2097 @item --extract-dwo
2098 Extract the contents of all DWARF .dwo sections. See the
2099 @option{--strip-dwo} option for more information.
2100
2101 @item --file-alignment @var{num}
2102 Specify the file alignment. Sections in the file will always begin at
2103 file offsets which are multiples of this number. This defaults to
2104 512.
2105 [This option is specific to PE targets.]
2106
2107 @item --heap @var{reserve}
2108 @itemx --heap @var{reserve},@var{commit}
2109 Specify the number of bytes of memory to reserve (and optionally commit)
2110 to be used as heap for this program.
2111 [This option is specific to PE targets.]
2112
2113 @item --image-base @var{value}
2114 Use @var{value} as the base address of your program or dll. This is
2115 the lowest memory location that will be used when your program or dll
2116 is loaded. To reduce the need to relocate and improve performance of
2117 your dlls, each should have a unique base address and not overlap any
2118 other dlls. The default is 0x400000 for executables, and 0x10000000
2119 for dlls.
2120 [This option is specific to PE targets.]
2121
2122 @item --section-alignment @var{num}
2123 Sets the section alignment field in the PE header. Sections in memory
2124 will always begin at addresses which are a multiple of this number.
2125 Defaults to 0x1000.
2126 [This option is specific to PE targets.]
2127
2128 @item --stack @var{reserve}
2129 @itemx --stack @var{reserve},@var{commit}
2130 Specify the number of bytes of memory to reserve (and optionally commit)
2131 to be used as stack for this program.
2132 [This option is specific to PE targets.]
2133
2134 @item --subsystem @var{which}
2135 @itemx --subsystem @var{which}:@var{major}
2136 @itemx --subsystem @var{which}:@var{major}.@var{minor}
2137 Specifies the subsystem under which your program will execute. The
2138 legal values for @var{which} are @code{native}, @code{windows},
2139 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2140 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2141 the subsystem version also. Numeric values are also accepted for
2142 @var{which}.
2143 [This option is specific to PE targets.]
2144
2145 @item --extract-symbol
2146 Keep the file's section flags and symbols but remove all section data.
2147 Specifically, the option:
2148
2149 @itemize
2150 @item removes the contents of all sections;
2151 @item sets the size of every section to zero; and
2152 @item sets the file's start address to zero.
2153 @end itemize
2154
2155 This option is used to build a @file{.sym} file for a VxWorks kernel.
2156 It can also be a useful way of reducing the size of a @option{--just-symbols}
2157 linker input file.
2158
2159 @item --compress-debug-sections
2160 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2161 ELF ABI. Note - if compression would actually make a section
2162 @emph{larger}, then it is not compressed.
2163
2164 @item --compress-debug-sections=none
2165 @itemx --compress-debug-sections=zlib
2166 @itemx --compress-debug-sections=zlib-gnu
2167 @itemx --compress-debug-sections=zlib-gabi
2168 @itemx --compress-debug-sections=zstd
2169 For ELF files, these options control how DWARF debug sections are
2170 compressed. @option{--compress-debug-sections=none} is equivalent
2171 to @option{--decompress-debug-sections}.
2172 @option{--compress-debug-sections=zlib} and
2173 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2174 @option{--compress-debug-sections}.
2175 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug sections
2176 using the obsoleted zlib-gnu format. The debug sections are renamed to begin
2177 with @samp{.zdebug}.
2178 @option{--compress-debug-sections=zstd} compresses DWARF debug
2179 sections using zstd. Note - if compression would actually make a section
2180 @emph{larger}, then it is not compressed nor renamed.
2181
2182 @item --decompress-debug-sections
2183 Decompress DWARF debug sections. For a @samp{.zdebug} section, the original
2184 name is restored.
2185
2186 @item --elf-stt-common=yes
2187 @itemx --elf-stt-common=no
2188 For ELF files, these options control whether common symbols should be
2189 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2190 @option{--elf-stt-common=yes} converts common symbol type to
2191 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2192 type to @code{STT_OBJECT}.
2193
2194 @item --merge-notes
2195 @itemx --no-merge-notes
2196 For ELF files, attempt (or do not attempt) to reduce the size of any
2197 SHT_NOTE type sections by removing duplicate notes.
2198
2199 @item -V
2200 @itemx --version
2201 Show the version number of @command{objcopy}.
2202
2203 @item --verilog-data-width=@var{bytes}
2204 For Verilog output, this options controls the number of bytes
2205 converted for each output data element. The input target controls the
2206 endianness of the conversion.
2207
2208 @item -v
2209 @itemx --verbose
2210 Verbose output: list all object files modified. In the case of
2211 archives, @samp{objcopy -V} lists all members of the archive.
2212
2213 @item --help
2214 Show a summary of the options to @command{objcopy}.
2215
2216 @item --info
2217 Display a list showing all architectures and object formats available.
2218 @end table
2219
2220 @c man end
2221
2222 @ignore
2223 @c man begin SEEALSO objcopy
2224 ld(1), objdump(1), and the Info entries for @file{binutils}.
2225 @c man end
2226 @end ignore
2227
2228 @node objdump
2229 @chapter objdump
2230
2231 @cindex object file information
2232 @kindex objdump
2233
2234 @c man title objdump display information from object files
2235
2236 @smallexample
2237 @c man begin SYNOPSIS objdump
2238 objdump [@option{-a}|@option{--archive-headers}]
2239 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2240 [@option{-C}|@option{--demangle}[=@var{style}] ]
2241 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2242 [@option{-D}|@option{--disassemble-all}]
2243 [@option{-z}|@option{--disassemble-zeroes}]
2244 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2245 [@option{-f}|@option{--file-headers}]
2246 [@option{-F}|@option{--file-offsets}]
2247 [@option{--file-start-context}]
2248 [@option{-g}|@option{--debugging}]
2249 [@option{-e}|@option{--debugging-tags}]
2250 [@option{-h}|@option{--section-headers}|@option{--headers}]
2251 [@option{-i}|@option{--info}]
2252 [@option{-j} @var{section}|@option{--section=}@var{section}]
2253 [@option{-l}|@option{--line-numbers}]
2254 [@option{-S}|@option{--source}]
2255 [@option{--source-comment}[=@var{text}]]
2256 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2257 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2258 [@option{-p}|@option{--private-headers}]
2259 [@option{-P} @var{options}|@option{--private=}@var{options}]
2260 [@option{-r}|@option{--reloc}]
2261 [@option{-R}|@option{--dynamic-reloc}]
2262 [@option{-s}|@option{--full-contents}]
2263 [@option{-W[lLiaprmfFsoORtUuTgAck]}|
2264 @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]]
2265 [@option{-WK}|@option{--dwarf=follow-links}]
2266 [@option{-WN}|@option{--dwarf=no-follow-links}]
2267 [@option{-wD}|@option{--dwarf=use-debuginfod}]
2268 [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
2269 [@option{-L}|@option{--process-links}]
2270 [@option{--ctf=}@var{section}]
2271 [@option{--sframe=}@var{section}]
2272 [@option{-G}|@option{--stabs}]
2273 [@option{-t}|@option{--syms}]
2274 [@option{-T}|@option{--dynamic-syms}]
2275 [@option{-x}|@option{--all-headers}]
2276 [@option{-w}|@option{--wide}]
2277 [@option{--start-address=}@var{address}]
2278 [@option{--stop-address=}@var{address}]
2279 [@option{--no-addresses}]
2280 [@option{--prefix-addresses}]
2281 [@option{--[no-]show-raw-insn}]
2282 [@option{--adjust-vma=}@var{offset}]
2283 [@option{--show-all-symbols}]
2284 [@option{--dwarf-depth=@var{n}}]
2285 [@option{--dwarf-start=@var{n}}]
2286 [@option{--ctf-parent=}@var{section}]
2287 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2288 [@option{--special-syms}]
2289 [@option{--prefix=}@var{prefix}]
2290 [@option{--prefix-strip=}@var{level}]
2291 [@option{--insn-width=}@var{width}]
2292 [@option{--visualize-jumps[=color|=extended-color|=off]}
2293 [@option{--disassembler-color=[off|terminal|on|extended]}
2294 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
2295 [@option{-V}|@option{--version}]
2296 [@option{-H}|@option{--help}]
2297 @var{objfile}@dots{}
2298 @c man end
2299 @end smallexample
2300
2301 @c man begin DESCRIPTION objdump
2302
2303 @command{objdump} displays information about one or more object files.
2304 The options control what particular information to display. This
2305 information is mostly useful to programmers who are working on the
2306 compilation tools, as opposed to programmers who just want their
2307 program to compile and work.
2308
2309 @var{objfile}@dots{} are the object files to be examined. When you
2310 specify archives, @command{objdump} shows information on each of the member
2311 object files.
2312
2313 @c man end
2314
2315 @c man begin OPTIONS objdump
2316
2317 The long and short forms of options, shown here as alternatives, are
2318 equivalent. At least one option from the list
2319 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2320
2321 @table @env
2322 @item -a
2323 @itemx --archive-header
2324 @cindex archive headers
2325 If any of the @var{objfile} files are archives, display the archive
2326 header information (in a format similar to @samp{ls -l}). Besides the
2327 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2328 the object file format of each archive member.
2329
2330 @item --adjust-vma=@var{offset}
2331 @cindex section addresses in objdump
2332 @cindex VMA in objdump
2333 When dumping information, first add @var{offset} to all the section
2334 addresses. This is useful if the section addresses do not correspond to
2335 the symbol table, which can happen when putting sections at particular
2336 addresses when using a format which can not represent section addresses,
2337 such as a.out.
2338
2339 @item -b @var{bfdname}
2340 @itemx --target=@var{bfdname}
2341 @cindex object code format
2342 Specify that the object-code format for the object files is
2343 @var{bfdname}. This option may not be necessary; @var{objdump} can
2344 automatically recognize many formats.
2345
2346 For example,
2347 @example
2348 objdump -b oasys -m vax -h fu.o
2349 @end example
2350 @noindent
2351 displays summary information from the section headers (@option{-h}) of
2352 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2353 file in the format produced by Oasys compilers. You can list the
2354 formats available with the @option{-i} option.
2355 @xref{Target Selection}, for more information.
2356
2357 @item -C
2358 @itemx --demangle[=@var{style}]
2359 @cindex demangling in objdump
2360 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2361 Besides removing any initial underscore prepended by the system, this
2362 makes C++ function names readable. Different compilers have different
2363 mangling styles. The optional demangling style argument can be used to
2364 choose an appropriate demangling style for your compiler. @xref{c++filt},
2365 for more information on demangling.
2366
2367 @item --recurse-limit
2368 @itemx --no-recurse-limit
2369 @itemx --recursion-limit
2370 @itemx --no-recursion-limit
2371 Enables or disables a limit on the amount of recursion performed
2372 whilst demangling strings. Since the name mangling formats allow for
2373 an infinite level of recursion it is possible to create strings whose
2374 decoding will exhaust the amount of stack space available on the host
2375 machine, triggering a memory fault. The limit tries to prevent this
2376 from happening by restricting recursion to 2048 levels of nesting.
2377
2378 The default is for this limit to be enabled, but disabling it may be
2379 necessary in order to demangle truly complicated names. Note however
2380 that if the recursion limit is disabled then stack exhaustion is
2381 possible and any bug reports about such an event will be rejected.
2382
2383 @item -g
2384 @itemx --debugging
2385 Display debugging information. This attempts to parse STABS
2386 debugging format information stored in the file and print it out using
2387 a C like syntax. If no STABS debugging was found this option
2388 falls back on the @option{-W} option to print any DWARF information in
2389 the file.
2390
2391 @item -e
2392 @itemx --debugging-tags
2393 Like @option{-g}, but the information is generated in a format compatible
2394 with ctags tool.
2395
2396 @item -d
2397 @itemx --disassemble
2398 @itemx --disassemble=@var{symbol}
2399 @cindex disassembling object code
2400 @cindex machine instructions
2401 Display the assembler mnemonics for the machine instructions from the
2402 input file. This option only disassembles those sections which are
2403 expected to contain instructions. If the optional @var{symbol}
2404 argument is given, then display the assembler mnemonics starting at
2405 @var{symbol}. If @var{symbol} is a function name then disassembly
2406 will stop at the end of the function, otherwise it will stop when the
2407 next symbol is encountered. If there are no matches for @var{symbol}
2408 then nothing will be displayed.
2409
2410 Note if the @option{--dwarf=follow-links} option is enabled
2411 then any symbol tables in linked debug info files will be read in and
2412 used when disassembling.
2413
2414 @item -D
2415 @itemx --disassemble-all
2416 Like @option{-d}, but disassemble the contents of all non-empty
2417 non-bss sections, not just those expected to contain instructions.
2418 @option{-j} may be used to select specific sections.
2419
2420 This option also has a subtle effect on the disassembly of
2421 instructions in code sections. When option @option{-d} is in effect
2422 objdump will assume that any symbols present in a code section occur
2423 on the boundary between instructions and it will refuse to disassemble
2424 across such a boundary. When option @option{-D} is in effect however
2425 this assumption is supressed. This means that it is possible for the
2426 output of @option{-d} and @option{-D} to differ if, for example, data
2427 is stored in code sections.
2428
2429 If the target is an ARM architecture this switch also has the effect
2430 of forcing the disassembler to decode pieces of data found in code
2431 sections as if they were instructions.
2432
2433 Note if the @option{--dwarf=follow-links} option is enabled
2434 then any symbol tables in linked debug info files will be read in and
2435 used when disassembling.
2436
2437 @item --no-addresses
2438 When disassembling, don't print addresses on each line or for symbols
2439 and relocation offsets. In combination with @option{--no-show-raw-insn}
2440 this may be useful for comparing compiler output.
2441
2442 @item --prefix-addresses
2443 When disassembling, print the complete address on each line. This is
2444 the older disassembly format.
2445
2446 @item -EB
2447 @itemx -EL
2448 @itemx --endian=@{big|little@}
2449 @cindex endianness
2450 @cindex disassembly endianness
2451 Specify the endianness of the object files. This only affects
2452 disassembly. This can be useful when disassembling a file format which
2453 does not describe endianness information, such as S-records.
2454
2455 @item -f
2456 @itemx --file-headers
2457 @cindex object file header
2458 Display summary information from the overall header of
2459 each of the @var{objfile} files.
2460
2461 @item -F
2462 @itemx --file-offsets
2463 @cindex object file offsets
2464 When disassembling sections, whenever a symbol is displayed, also
2465 display the file offset of the region of data that is about to be
2466 dumped. If zeroes are being skipped, then when disassembly resumes,
2467 tell the user how many zeroes were skipped and the file offset of the
2468 location from where the disassembly resumes. When dumping sections,
2469 display the file offset of the location from where the dump starts.
2470
2471 @item --file-start-context
2472 @cindex source code context
2473 Specify that when displaying interlisted source code/disassembly
2474 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2475 context to the start of the file.
2476
2477 @item -h
2478 @itemx --section-headers
2479 @itemx --headers
2480 @cindex section headers
2481 Display summary information from the section headers of the
2482 object file.
2483
2484 File segments may be relocated to nonstandard addresses, for example by
2485 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2486 @command{ld}. However, some object file formats, such as a.out, do not
2487 store the starting address of the file segments. In those situations,
2488 although @command{ld} relocates the sections correctly, using @samp{objdump
2489 -h} to list the file section headers cannot show the correct addresses.
2490 Instead, it shows the usual addresses, which are implicit for the
2491 target.
2492
2493 Note, in some cases it is possible for a section to have both the
2494 READONLY and the NOREAD attributes set. In such cases the NOREAD
2495 attribute takes precedence, but @command{objdump} will report both
2496 since the exact setting of the flag bits might be important.
2497
2498 @item -H
2499 @itemx --help
2500 Print a summary of the options to @command{objdump} and exit.
2501
2502 @item -i
2503 @itemx --info
2504 @cindex architectures available
2505 @cindex object formats available
2506 Display a list showing all architectures and object formats available
2507 for specification with @option{-b} or @option{-m}.
2508
2509 @item -j @var{name}
2510 @itemx --section=@var{name}
2511 @cindex section information
2512 Display information for section @var{name}. This option may be
2513 specified multiple times.
2514
2515 @item -L
2516 @itemx --process-links
2517 Display the contents of non-debug sections found in separate debuginfo
2518 files that are linked to the main file. This option automatically
2519 implies the @option{-WK} option, and only sections requested by other
2520 command line options will be displayed.
2521
2522 @item -l
2523 @itemx --line-numbers
2524 @cindex source filenames for object files
2525 Label the display (using debugging information) with the filename and
2526 source line numbers corresponding to the object code or relocs shown.
2527 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2528
2529 @item -m @var{machine}
2530 @itemx --architecture=@var{machine}
2531 @cindex architecture
2532 @cindex disassembly architecture
2533 Specify the architecture to use when disassembling object files. This
2534 can be useful when disassembling object files which do not describe
2535 architecture information, such as S-records. You can list the available
2536 architectures with the @option{-i} option.
2537
2538 For most architectures it is possible to supply an architecture
2539 name and a machine name, separated by a colon. For example
2540 @samp{foo:bar} would refer to the @samp{bar} machine type in the
2541 @samp{foo} architecture. This can be helpful if objdump has been
2542 configured to support multiple architectures.
2543
2544 If the target is an ARM architecture then this switch has an
2545 additional effect. It restricts the disassembly to only those
2546 instructions supported by the architecture specified by @var{machine}.
2547 If it is necessary to use this switch because the input file does not
2548 contain any architecture information, but it is also desired to
2549 disassemble all the instructions use @option{-marm}.
2550
2551 @item -M @var{options}
2552 @itemx --disassembler-options=@var{options}
2553 Pass target specific information to the disassembler. Only supported on
2554 some targets. If it is necessary to specify more than one
2555 disassembler option then multiple @option{-M} options can be used or
2556 can be placed together into a comma separated list.
2557
2558 For ARC, @option{dsp} controls the printing of DSP instructions,
2559 @option{spfp} selects the printing of FPX single precision FP
2560 instructions, @option{dpfp} selects the printing of FPX double
2561 precision FP instructions, @option{quarkse_em} selects the printing of
2562 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2563 of double precision assist instructions, @option{fpus} selects the
2564 printing of FPU single precision FP instructions, while @option{fpud}
2565 selects the printing of FPU double precision FP instructions.
2566 Additionally, one can choose to have all the immediates printed in
2567 hexadecimal using @option{hex}. By default, the short immediates are
2568 printed using the decimal representation, while the long immediate
2569 values are printed as hexadecimal.
2570
2571 @option{cpu=...} allows one to enforce a particular ISA when disassembling
2572 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2573 This might be useful to select ARC EM or HS ISA, because architecture is same
2574 for those and disassembler relies on private ELF header data to decide if code
2575 is for EM or HS. This option might be specified multiple times - only the
2576 latest value will be used. Valid values are same as for the assembler
2577 @option{-mcpu=...} option.
2578
2579 If the target is an ARM architecture then this switch can be used to
2580 select which register name set is used during disassembler. Specifying
2581 @option{-M reg-names-std} (the default) will select the register names as
2582 used in ARM's instruction set documentation, but with register 13 called
2583 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2584 @option{-M reg-names-apcs} will select the name set used by the ARM
2585 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2586 just use @samp{r} followed by the register number.
2587
2588 There are also two variants on the APCS register naming scheme enabled
2589 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2590 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2591 with the normal register names or the special register names).
2592
2593 This option can also be used for ARM architectures to force the
2594 disassembler to interpret all instructions as Thumb instructions by
2595 using the switch @option{--disassembler-options=force-thumb}. This can be
2596 useful when attempting to disassemble thumb code produced by other
2597 compilers.
2598
2599 For AArch64 targets this switch can be used to set whether instructions are
2600 disassembled as the most general instruction using the @option{-M no-aliases}
2601 option or whether instruction notes should be generated as comments in the
2602 disasssembly using @option{-M notes}.
2603
2604 For the x86, some of the options duplicate functions of the @option{-m}
2605 switch, but allow finer grained control.
2606 @table @code
2607 @item x86-64
2608 @itemx i386
2609 @itemx i8086
2610 Select disassembly for the given architecture.
2611
2612 @item intel
2613 @itemx att
2614 Select between intel syntax mode and AT&T syntax mode.
2615
2616 @item amd64
2617 @itemx intel64
2618 Select between AMD64 ISA and Intel64 ISA.
2619
2620 @item intel-mnemonic
2621 @itemx att-mnemonic
2622 Select between intel mnemonic mode and AT&T mnemonic mode.
2623 Note: @code{intel-mnemonic} implies @code{intel} and
2624 @code{att-mnemonic} implies @code{att}.
2625
2626 @item addr64
2627 @itemx addr32
2628 @itemx addr16
2629 @itemx data32
2630 @itemx data16
2631 Specify the default address size and operand size. These five options
2632 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2633 appear later in the option string.
2634
2635 @item suffix
2636 When in AT&T mode and also for a limited set of instructions when in Intel
2637 mode, instructs the disassembler to print a mnemonic suffix even when the
2638 suffix could be inferred by the operands or, for certain instructions, the
2639 execution mode's defaults.
2640 @end table
2641
2642 For PowerPC, the @option{-M} argument @option{raw} selects
2643 disasssembly of hardware insns rather than aliases. For example, you
2644 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2645 rather than @code{li}. All of the @option{-m} arguments for
2646 @command{gas} that select a CPU are supported. These are:
2647 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2648 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2649 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2650 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2651 @option{booke32}, @option{cell}, @option{com}, @option{e200z2}, @option{e200z4},
2652 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2653 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2654 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2655 @option{power8}, @option{power9}, @option{power10}, @option{ppc},
2656 @option{ppc32}, @option{ppc64}, @option{ppc64bridge}, @option{ppcps},
2657 @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2658 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9}, @option{pwr10},
2659 @option{pwrx}, @option{titan}, @option{vle}, and @option{future}.
2660 @option{32} and @option{64} modify the default or a prior CPU
2661 selection, disabling and enabling 64-bit insns respectively. In
2662 addition, @option{altivec}, @option{any}, @option{lsp}, @option{htm},
2663 @option{vsx}, @option{spe} and @option{spe2} add capabilities to a
2664 previous @emph{or later} CPU selection.
2665 @option{any} will disassemble any opcode known to
2666 binutils, but in cases where an opcode has two different meanings or
2667 different arguments, you may not see the disassembly you expect.
2668 If you disassemble without giving a CPU selection, a default will be
2669 chosen from information gleaned by BFD from the object files headers,
2670 but the result again may not be as you expect.
2671
2672 For MIPS, this option controls the printing of instruction mnemonic
2673 names and register names in disassembled instructions. Multiple
2674 selections from the following may be specified as a comma separated
2675 string, and invalid options are ignored:
2676
2677 @table @code
2678 @item no-aliases
2679 Print the 'raw' instruction mnemonic instead of some pseudo
2680 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2681 'sll' instead of 'nop', etc.
2682
2683 @item msa
2684 Disassemble MSA instructions.
2685
2686 @item virt
2687 Disassemble the virtualization ASE instructions.
2688
2689 @item xpa
2690 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2691
2692 @item gpr-names=@var{ABI}
2693 Print GPR (general-purpose register) names as appropriate
2694 for the specified ABI. By default, GPR names are selected according to
2695 the ABI of the binary being disassembled.
2696
2697 @item fpr-names=@var{ABI}
2698 Print FPR (floating-point register) names as
2699 appropriate for the specified ABI. By default, FPR numbers are printed
2700 rather than names.
2701
2702 @item cp0-names=@var{ARCH}
2703 Print CP0 (system control coprocessor; coprocessor 0) register names
2704 as appropriate for the CPU or architecture specified by
2705 @var{ARCH}. By default, CP0 register names are selected according to
2706 the architecture and CPU of the binary being disassembled.
2707
2708 @item hwr-names=@var{ARCH}
2709 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2710 as appropriate for the CPU or architecture specified by
2711 @var{ARCH}. By default, HWR names are selected according to
2712 the architecture and CPU of the binary being disassembled.
2713
2714 @item reg-names=@var{ABI}
2715 Print GPR and FPR names as appropriate for the selected ABI.
2716
2717 @item reg-names=@var{ARCH}
2718 Print CPU-specific register names (CP0 register and HWR names)
2719 as appropriate for the selected CPU or architecture.
2720 @end table
2721
2722 For any of the options listed above, @var{ABI} or
2723 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2724 rather than names, for the selected types of registers.
2725 You can list the available values of @var{ABI} and @var{ARCH} using
2726 the @option{--help} option.
2727
2728 For VAX, you can specify function entry addresses with @option{-M
2729 entry:0xf00ba}. You can use this multiple times to properly
2730 disassemble VAX binary files that don't contain symbol tables (like
2731 ROM dumps). In these cases, the function entry mask would otherwise
2732 be decoded as VAX instructions, which would probably lead the rest
2733 of the function being wrongly disassembled.
2734
2735 @item -p
2736 @itemx --private-headers
2737 Print information that is specific to the object file format. The exact
2738 information printed depends upon the object file format. For some
2739 object file formats, no additional information is printed.
2740
2741 @item -P @var{options}
2742 @itemx --private=@var{options}
2743 Print information that is specific to the object file format. The
2744 argument @var{options} is a comma separated list that depends on the
2745 format (the lists of options is displayed with the help).
2746
2747 For XCOFF, the available options are:
2748 @table @code
2749 @item header
2750 @item aout
2751 @item sections
2752 @item syms
2753 @item relocs
2754 @item lineno,
2755 @item loader
2756 @item except
2757 @item typchk
2758 @item traceback
2759 @item toc
2760 @item ldinfo
2761 @end table
2762
2763 For PE, the available options are:
2764 @table @code
2765 @item header
2766 @item sections
2767 @end table
2768
2769 Not all object formats support this option. In particular the ELF
2770 format does not use it.
2771
2772 @item -r
2773 @itemx --reloc
2774 @cindex relocation entries, in object file
2775 Print the relocation entries of the file. If used with @option{-d} or
2776 @option{-D}, the relocations are printed interspersed with the
2777 disassembly.
2778
2779 @item -R
2780 @itemx --dynamic-reloc
2781 @cindex dynamic relocation entries, in object file
2782 Print the dynamic relocation entries of the file. This is only
2783 meaningful for dynamic objects, such as certain types of shared
2784 libraries. As for @option{-r}, if used with @option{-d} or
2785 @option{-D}, the relocations are printed interspersed with the
2786 disassembly.
2787
2788 @item -s
2789 @itemx --full-contents
2790 @cindex sections, full contents
2791 @cindex object file sections
2792 Display the full contents of sections, often used in combination with
2793 @option{-j} to request specific sections. By default all non-empty
2794 non-bss sections are displayed.
2795
2796 @item -S
2797 @itemx --source
2798 @cindex source disassembly
2799 @cindex disassembly, with source
2800 Display source code intermixed with disassembly, if possible. Implies
2801 @option{-d}.
2802
2803 @item --show-all-symbols
2804 When disassembling, show all the symbols that match a given address,
2805 not just the first one.
2806
2807 @item --source-comment[=@var{txt}]
2808 @cindex source disassembly
2809 @cindex disassembly, with source
2810 Like the @option{-S} option, but all source code lines are displayed
2811 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2812 string which can be used to distinguish the assembler code from the
2813 source code. If @var{txt} is not provided then a default string of
2814 @var{``# ``} (hash followed by a space), will be used.
2815
2816 @item --prefix=@var{prefix}
2817 @cindex Add prefix to absolute paths
2818 Specify @var{prefix} to add to the absolute paths when used with
2819 @option{-S}.
2820
2821 @item --prefix-strip=@var{level}
2822 @cindex Strip absolute paths
2823 Indicate how many initial directory names to strip off the hardwired
2824 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2825
2826 @item --show-raw-insn
2827 When disassembling instructions, print the instruction in hex as well as
2828 in symbolic form. This is the default except when
2829 @option{--prefix-addresses} is used.
2830
2831 @item --no-show-raw-insn
2832 When disassembling instructions, do not print the instruction bytes.
2833 This is the default when @option{--prefix-addresses} is used.
2834
2835 @item --insn-width=@var{width}
2836 @cindex Instruction width
2837 Display @var{width} bytes on a single line when disassembling
2838 instructions.
2839
2840 @item --visualize-jumps[=color|=extended-color|=off]
2841 Visualize jumps that stay inside a function by drawing ASCII art between
2842 the start and target addresses. The optional @option{=color} argument
2843 adds color to the output using simple terminal colors. Alternatively
2844 the @option{=extended-color} argument will add color using 8bit
2845 colors, but these might not work on all terminals.
2846
2847 If it is necessary to disable the @option{visualize-jumps} option
2848 after it has previously been enabled then use
2849 @option{visualize-jumps=off}.
2850
2851 @item --disassembler-color=off
2852 @itemx --disassembler-color=terminal
2853 @itemx --disassembler-color=on|color|colour
2854 @itemx --disassembler-color=extened|extended-color|extened-colour
2855 Enables or disables the use of colored syntax highlighting in
2856 disassembly output. The default behaviour is determined via a
2857 configure time option. Note, not all architectures support colored
2858 syntax highlighting, and depending upon the terminal used, colored
2859 output may not actually be legible.
2860
2861 The @option{on} argument adds colors using simple terminal colors.
2862
2863 The @option{terminal} argument does the same, but only if the output
2864 device is a terminal.
2865
2866 The @option{extended-color} argument is similar to the @option{on}
2867 argument, but it uses 8-bit colors. These may not work on all
2868 terminals.
2869
2870 The @option{off} argument disables colored disassembly.
2871
2872 @item -W[lLiaprmfFsoORtUuTgAckK]
2873 @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]
2874 @include debug.options.texi
2875
2876 @item --dwarf-check
2877 Enable additional checks for consistency of Dwarf information.
2878
2879 @include ctf.options.texi
2880
2881 @include sframe.options.texi
2882
2883 @item -G
2884 @itemx --stabs
2885 @cindex stab
2886 @cindex .stab
2887 @cindex debug symbols
2888 @cindex ELF object file format
2889 Display the full contents of any sections requested. Display the
2890 contents of the .stab and .stab.index and .stab.excl sections from an
2891 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2892 @code{.stab} debugging symbol-table entries are carried in an ELF
2893 section. In most other file formats, debugging symbol-table entries are
2894 interleaved with linkage symbols, and are visible in the @option{--syms}
2895 output.
2896
2897 @item --start-address=@var{address}
2898 @cindex start-address
2899 Start displaying data at the specified address. This affects the output
2900 of the @option{-d}, @option{-r} and @option{-s} options.
2901
2902 @item --stop-address=@var{address}
2903 @cindex stop-address
2904 Stop displaying data at the specified address. This affects the output
2905 of the @option{-d}, @option{-r} and @option{-s} options.
2906
2907 @item -t
2908 @itemx --syms
2909 @cindex symbol table entries, printing
2910 Print the symbol table entries of the file.
2911 This is similar to the information provided by the @samp{nm} program,
2912 although the display format is different. The format of the output
2913 depends upon the format of the file being dumped, but there are two main
2914 types. One looks like this:
2915
2916 @smallexample
2917 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2918 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2919 @end smallexample
2920
2921 where the number inside the square brackets is the number of the entry
2922 in the symbol table, the @var{sec} number is the section number, the
2923 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2924 symbol's type, the @var{scl} number is the symbol's storage class and
2925 the @var{nx} value is the number of auxiliary entries associated with
2926 the symbol. The last two fields are the symbol's value and its name.
2927
2928 The other common output format, usually seen with ELF based files,
2929 looks like this:
2930
2931 @smallexample
2932 00000000 l d .bss 00000000 .bss
2933 00000000 g .text 00000000 fred
2934 @end smallexample
2935
2936 Here the first number is the symbol's value (sometimes referred to as
2937 its address). The next field is actually a set of characters and
2938 spaces indicating the flag bits that are set on the symbol. These
2939 characters are described below. Next is the section with which the
2940 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2941 not connected with any section), or @emph{*UND*} if the section is
2942 referenced in the file being dumped, but not defined there.
2943
2944 After the section name comes another field, a number, which for common
2945 symbols is the alignment and for other symbol is the size. Finally
2946 the symbol's name is displayed.
2947
2948 The flag characters are divided into 7 groups as follows:
2949 @table @code
2950 @item l
2951 @itemx g
2952 @itemx u
2953 @itemx !
2954 The symbol is a local (l), global (g), unique global (u), neither
2955 global nor local (a space) or both global and local (!). A
2956 symbol can be neither local or global for a variety of reasons, e.g.,
2957 because it is used for debugging, but it is probably an indication of
2958 a bug if it is ever both local and global. Unique global symbols are
2959 a GNU extension to the standard set of ELF symbol bindings. For such
2960 a symbol the dynamic linker will make sure that in the entire process
2961 there is just one symbol with this name and type in use.
2962
2963 @item w
2964 The symbol is weak (w) or strong (a space).
2965
2966 @item C
2967 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2968
2969 @item W
2970 The symbol is a warning (W) or a normal symbol (a space). A warning
2971 symbol's name is a message to be displayed if the symbol following the
2972 warning symbol is ever referenced.
2973
2974 @item I
2975 @item i
2976 The symbol is an indirect reference to another symbol (I), a function
2977 to be evaluated during reloc processing (i) or a normal symbol (a
2978 space).
2979
2980 @item d
2981 @itemx D
2982 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2983 normal symbol (a space).
2984
2985 @item F
2986 @item f
2987 @item O
2988 The symbol is the name of a function (F) or a file (f) or an object
2989 (O) or just a normal symbol (a space).
2990 @end table
2991
2992 @item -T
2993 @itemx --dynamic-syms
2994 @cindex dynamic symbol table entries, printing
2995 Print the dynamic symbol table entries of the file. This is only
2996 meaningful for dynamic objects, such as certain types of shared
2997 libraries. This is similar to the information provided by the @samp{nm}
2998 program when given the @option{-D} (@option{--dynamic}) option.
2999
3000 The output format is similar to that produced by the @option{--syms}
3001 option, except that an extra field is inserted before the symbol's
3002 name, giving the version information associated with the symbol.
3003 If the version is the default version to be used when resolving
3004 unversioned references to the symbol then it's displayed as is,
3005 otherwise it's put into parentheses.
3006
3007 @item --special-syms
3008 When displaying symbols include those which the target considers to be
3009 special in some way and which would not normally be of interest to the
3010 user.
3011
3012 @item -U @var{[d|i|l|e|x|h]}
3013 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3014 Controls the display of UTF-8 encoded multibyte characters in strings.
3015 The default (@option{--unicode=default}) is to give them no special
3016 treatment. The @option{--unicode=locale} option displays the sequence
3017 in the current locale, which may or may not support them. The options
3018 @option{--unicode=hex} and @option{--unicode=invalid} display them as
3019 hex byte sequences enclosed by either angle brackets or curly braces.
3020
3021 The @option{--unicode=escape} option displays them as escape sequences
3022 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
3023 them as escape sequences highlighted in red (if supported by the
3024 output device). The colouring is intended to draw attention to the
3025 presence of unicode sequences where they might not be expected.
3026
3027 @item -V
3028 @itemx --version
3029 Print the version number of @command{objdump} and exit.
3030
3031 @item -x
3032 @itemx --all-headers
3033 @cindex all header information, object file
3034 @cindex header information, all
3035 Display all available header information, including the symbol table and
3036 relocation entries. Using @option{-x} is equivalent to specifying all of
3037 @option{-a -f -h -p -r -t}.
3038
3039 @item -w
3040 @itemx --wide
3041 @cindex wide output, printing
3042 Format some lines for output devices that have more than 80 columns.
3043 Also do not truncate symbol names when they are displayed.
3044
3045 @item -z
3046 @itemx --disassemble-zeroes
3047 Normally the disassembly output will skip blocks of zeroes. This
3048 option directs the disassembler to disassemble those blocks, just like
3049 any other data.
3050 @end table
3051
3052 @c man end
3053
3054 @ignore
3055 @c man begin SEEALSO objdump
3056 nm(1), readelf(1), and the Info entries for @file{binutils}.
3057 @c man end
3058 @end ignore
3059
3060 @node ranlib
3061 @chapter ranlib
3062
3063 @kindex ranlib
3064 @cindex archive contents
3065 @cindex symbol index
3066
3067 @c man title ranlib generate an index to an archive
3068
3069 @smallexample
3070 @c man begin SYNOPSIS ranlib
3071 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
3072 @c man end
3073 @end smallexample
3074
3075 @c man begin DESCRIPTION ranlib
3076
3077 @command{ranlib} generates an index to the contents of an archive and
3078 stores it in the archive. The index lists each symbol defined by a
3079 member of an archive that is a relocatable object file.
3080
3081 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
3082
3083 An archive with such an index speeds up linking to the library and
3084 allows routines in the library to call each other without regard to
3085 their placement in the archive.
3086
3087 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
3088 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
3089 @xref{ar}.
3090
3091 @c man end
3092
3093 @c man begin OPTIONS ranlib
3094
3095 @table @env
3096 @item -h
3097 @itemx -H
3098 @itemx --help
3099 Show usage information for @command{ranlib}.
3100
3101 @item -v
3102 @itemx -V
3103 @itemx --version
3104 Show the version number of @command{ranlib}.
3105
3106 @item -D
3107 @cindex deterministic archives
3108 @kindex --enable-deterministic-archives
3109 Operate in @emph{deterministic} mode. The symbol map archive member's
3110 header will show zero for the UID, GID, and timestamp. When this
3111 option is used, multiple runs will produce identical output files.
3112
3113 If @file{binutils} was configured with
3114 @option{--enable-deterministic-archives}, then this mode is on by
3115 default. It can be disabled with the @samp{-U} option, described
3116 below.
3117
3118 @item -t
3119 Update the timestamp of the symbol map of an archive.
3120
3121 @item -U
3122 @cindex deterministic archives
3123 @kindex --enable-deterministic-archives
3124 Do @emph{not} operate in @emph{deterministic} mode. This is the
3125 inverse of the @samp{-D} option, above: the archive index will get
3126 actual UID, GID, timestamp, and file mode values.
3127
3128 If @file{binutils} was configured @emph{without}
3129 @option{--enable-deterministic-archives}, then this mode is on by
3130 default.
3131
3132 @end table
3133
3134 @c man end
3135
3136 @ignore
3137 @c man begin SEEALSO ranlib
3138 ar(1), nm(1), and the Info entries for @file{binutils}.
3139 @c man end
3140 @end ignore
3141
3142 @node size
3143 @chapter size
3144
3145 @kindex size
3146 @cindex section sizes
3147
3148 @c man title size list section sizes and total size of binary files
3149
3150 @smallexample
3151 @c man begin SYNOPSIS size
3152 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
3153 [@option{--help}]
3154 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
3155 [@option{--common}]
3156 [@option{-t}|@option{--totals}]
3157 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
3158 [@option{-f}]
3159 [@var{objfile}@dots{}]
3160 @c man end
3161 @end smallexample
3162
3163 @c man begin DESCRIPTION size
3164
3165 The @sc{gnu} @command{size} utility lists the section sizes and the total
3166 size for each of the binary files @var{objfile} on its argument list.
3167 By default, one line of output is generated for each file or each
3168 module if the file is an archive.
3169
3170 @var{objfile}@dots{} are the files to be examined. If none are
3171 specified, the file @code{a.out} will be used instead.
3172
3173 @c man end
3174
3175 @c man begin OPTIONS size
3176
3177 The command-line options have the following meanings:
3178
3179 @table @env
3180 @item -A
3181 @itemx -B
3182 @itemx -G
3183 @itemx --format=@var{compatibility}
3184 @cindex @command{size} display format
3185 Using one of these options, you can choose whether the output from @sc{gnu}
3186 @command{size} resembles output from System V @command{size} (using @option{-A},
3187 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3188 @option{--format=berkeley}). The default is the one-line format similar to
3189 Berkeley's. Alternatively, you can choose the GNU format output
3190 (using @option{-G}, or @option{--format=gnu}), this is similar to
3191 Berkeley's output format, but sizes are counted differently.
3192 @c Bonus for doc-source readers: you can also say --format=strange (or
3193 @c anything else that starts with 's') for sysv, and --format=boring (or
3194 @c anything else that starts with 'b') for Berkeley.
3195
3196 Here is an example of the Berkeley (default) format of output from
3197 @command{size}:
3198 @smallexample
3199 $ size --format=Berkeley ranlib size
3200 text data bss dec hex filename
3201 294880 81920 11592 388392 5ed28 ranlib
3202 294880 81920 11888 388688 5ee50 size
3203 @end smallexample
3204
3205 The Berkeley style output counts read only data in the @code{text}
3206 column, not in the @code{data} column, the @code{dec} and @code{hex}
3207 columns both display the sum of the @code{text}, @code{data}, and
3208 @code{bss} columns in decimal and hexadecimal respectively.
3209
3210 The GNU format counts read only data in the @code{data} column, not
3211 the @code{text} column, and only displays the sum of the @code{text},
3212 @code{data}, and @code{bss} columns once, in the @code{total} column.
3213 The @option{--radix} option can be used to change the number base for
3214 all columns. Here is the same data displayed with GNU conventions:
3215
3216 @smallexample
3217 $ size --format=GNU ranlib size
3218 text data bss total filename
3219 279880 96920 11592 388392 ranlib
3220 279880 96920 11888 388688 size
3221 @end smallexample
3222
3223 @noindent
3224 This is the same data, but displayed closer to System V conventions:
3225
3226 @smallexample
3227 $ size --format=SysV ranlib size
3228 ranlib :
3229 section size addr
3230 .text 294880 8192
3231 .data 81920 303104
3232 .bss 11592 385024
3233 Total 388392
3234
3235
3236 size :
3237 section size addr
3238 .text 294880 8192
3239 .data 81920 303104
3240 .bss 11888 385024
3241 Total 388688
3242 @end smallexample
3243
3244 @item --help
3245 @itemx -h
3246 @itemx -H
3247 @item -?
3248 Show a summary of acceptable arguments and options.
3249
3250 @item -d
3251 @itemx -o
3252 @itemx -x
3253 @itemx --radix=@var{number}
3254 @cindex @command{size} number format
3255 @cindex radix for section sizes
3256 Using one of these options, you can control whether the size of each
3257 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3258 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3259 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3260 values (8, 10, 16) are supported. The total size is always given in two
3261 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3262 octal and hexadecimal if you're using @option{-o}.
3263
3264 @item --common
3265 Print total size of common symbols in each file. When using Berkeley
3266 or GNU format these are included in the bss size.
3267
3268 @item -t
3269 @itemx --totals
3270 Show totals of all objects listed (Berkeley or GNU format mode only).
3271
3272 @item --target=@var{bfdname}
3273 @cindex object code format
3274 Specify that the object-code format for @var{objfile} is
3275 @var{bfdname}. This option may not be necessary; @command{size} can
3276 automatically recognize many formats.
3277 @xref{Target Selection}, for more information.
3278
3279 @item -v
3280 @item -V
3281 @itemx --version
3282 Display the version number of @command{size}.
3283
3284 @item -f
3285 Ignored. This option is used by other versions of the @command{size}
3286 program, but it is not supported by the GNU Binutils version.
3287
3288 @end table
3289
3290 @c man end
3291
3292 @ignore
3293 @c man begin SEEALSO size
3294 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3295 @c man end
3296 @end ignore
3297
3298 @node strings
3299 @chapter strings
3300 @kindex strings
3301 @cindex listings strings
3302 @cindex printing strings
3303 @cindex strings, printing
3304
3305 @c man title strings print the sequences of printable characters in files
3306
3307 @smallexample
3308 @c man begin SYNOPSIS strings
3309 strings [@option{-afovV}] [@option{-}@var{min-len}]
3310 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3311 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3312 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3313 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
3314 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3315 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3316 [@option{-w}] [@option{--include-all-whitespace}]
3317 [@option{-s}] [@option{--output-separator} @var{sep_string}]
3318 [@option{--help}] [@option{--version}] @var{file}@dots{}
3319 @c man end
3320 @end smallexample
3321
3322 @c man begin DESCRIPTION strings
3323
3324 For each @var{file} given, @sc{gnu} @command{strings} prints the
3325 printable character sequences that are at least 4 characters long (or
3326 the number given with the options below) and are followed by an
3327 unprintable character.
3328
3329 Depending upon how the strings program was configured it will default
3330 to either displaying all the printable sequences that it can find in
3331 each file, or only those sequences that are in loadable, initialized
3332 data sections. If the file type is unrecognizable, or if strings is
3333 reading from stdin then it will always display all of the printable
3334 sequences that it can find.
3335
3336 For backwards compatibility any file that occurs after a command-line
3337 option of just @option{-} will also be scanned in full, regardless of
3338 the presence of any @option{-d} option.
3339
3340 @command{strings} is mainly useful for determining the contents of
3341 non-text files.
3342
3343 @c man end
3344
3345 @c man begin OPTIONS strings
3346
3347 @table @env
3348 @item -a
3349 @itemx --all
3350 @itemx -
3351 Scan the whole file, regardless of what sections it contains or
3352 whether those sections are loaded or initialized. Normally this is
3353 the default behaviour, but strings can be configured so that the
3354 @option{-d} is the default instead.
3355
3356 The @option{-} option is position dependent and forces strings to
3357 perform full scans of any file that is mentioned after the @option{-}
3358 on the command line, even if the @option{-d} option has been
3359 specified.
3360
3361 @item -d
3362 @itemx --data
3363 Only print strings from initialized, loaded data sections in the
3364 file. This may reduce the amount of garbage in the output, but it
3365 also exposes the strings program to any security flaws that may be
3366 present in the BFD library used to scan and load sections. Strings
3367 can be configured so that this option is the default behaviour. In
3368 such cases the @option{-a} option can be used to avoid using the BFD
3369 library and instead just print all of the strings found in the file.
3370
3371 @item -f
3372 @itemx --print-file-name
3373 Print the name of the file before each string.
3374
3375 @item --help
3376 Print a summary of the program usage on the standard output and exit.
3377
3378 @item -@var{min-len}
3379 @itemx -n @var{min-len}
3380 @itemx --bytes=@var{min-len}
3381 Print sequences of displayable characters that are at least
3382 @var{min-len} characters long. If not specified a default minimum
3383 length of 4 is used. The distinction between displayable and
3384 non-displayable characters depends upon the setting of the
3385 @option{-e} and @option{-U} options. Sequences are always terminated
3386 at control characters such as new-line and carriage-return, but not
3387 the tab character.
3388
3389 @item -o
3390 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3391 act like @samp{-t d} instead. Since we can not be compatible with both
3392 ways, we simply chose one.
3393
3394 @item -t @var{radix}
3395 @itemx --radix=@var{radix}
3396 Print the offset within the file before each string. The single
3397 character argument specifies the radix of the offset---@samp{o} for
3398 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3399
3400 @item -e @var{encoding}
3401 @itemx --encoding=@var{encoding}
3402 Select the character encoding of the strings that are to be found.
3403 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3404 characters (default), @samp{S} =
3405 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3406 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3407 littleendian. Useful for finding wide character strings. (@samp{l}
3408 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3409
3410 @item -U @var{[d|i|l|e|x|h]}
3411 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3412 Controls the display of UTF-8 encoded multibyte characters in strings.
3413 The default (@option{--unicode=default}) is to give them no special
3414 treatment, and instead rely upon the setting of the
3415 @option{--encoding} option. The other values for this option
3416 automatically enable @option{--encoding=S}.
3417
3418 The @option{--unicode=invalid} option treats them as non-graphic
3419 characters and hence not part of a valid string. All the remaining
3420 options treat them as valid string characters.
3421
3422 The @option{--unicode=locale} option displays them in the current
3423 locale, which may or may not support UTF-8 encoding. The
3424 @option{--unicode=hex} option displays them as hex byte sequences
3425 enclosed between @var{<>} characters. The @option{--unicode=escape}
3426 option displays them as escape sequences (@var{\uxxxx}) and the
3427 @option{--unicode=highlight} option displays them as escape sequences
3428 highlighted in red (if supported by the output device). The colouring
3429 is intended to draw attention to the presence of unicode sequences
3430 where they might not be expected.
3431
3432 @item -T @var{bfdname}
3433 @itemx --target=@var{bfdname}
3434 @cindex object code format
3435 Specify an object code format other than your system's default format.
3436 @xref{Target Selection}, for more information.
3437
3438 @item -v
3439 @itemx -V
3440 @itemx --version
3441 Print the program version number on the standard output and exit.
3442
3443 @item -w
3444 @itemx --include-all-whitespace
3445 By default tab and space characters are included in the strings that
3446 are displayed, but other whitespace characters, such a newlines and
3447 carriage returns, are not. The @option{-w} option changes this so
3448 that all whitespace characters are considered to be part of a string.
3449
3450 @item -s
3451 @itemx --output-separator
3452 By default, output strings are delimited by a new-line. This option
3453 allows you to supply any string to be used as the output record
3454 separator. Useful with --include-all-whitespace where strings
3455 may contain new-lines internally.
3456 @end table
3457
3458 @c man end
3459
3460 @ignore
3461 @c man begin SEEALSO strings
3462 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3463 and the Info entries for @file{binutils}.
3464 @c man end
3465 @end ignore
3466
3467 @node strip
3468 @chapter strip
3469
3470 @kindex strip
3471 @cindex removing symbols
3472 @cindex discarding symbols
3473 @cindex symbols, discarding
3474
3475 @c man title strip discard symbols and other data from object files
3476
3477 @smallexample
3478 @c man begin SYNOPSIS strip
3479 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3480 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3481 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3482 [@option{-s}|@option{--strip-all}]
3483 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3484 [@option{--strip-dwo}]
3485 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3486 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3487 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3488 [@option{-w}|@option{--wildcard}]
3489 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3490 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3491 [@option{--keep-section=}@var{sectionpattern}]
3492 [@option{--remove-relocations=}@var{sectionpattern}]
3493 [@option{--strip-section-headers}]
3494 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3495 [@option{-D}|@option{--enable-deterministic-archives}]
3496 [@option{-U}|@option{--disable-deterministic-archives}]
3497 [@option{--keep-section-symbols}]
3498 [@option{--keep-file-symbols}]
3499 [@option{--only-keep-debug}]
3500 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3501 [@option{--help}] [@option{--info}]
3502 @var{objfile}@dots{}
3503 @c man end
3504 @end smallexample
3505
3506 @c man begin DESCRIPTION strip
3507
3508 @sc{gnu} @command{strip} discards all symbols from object files
3509 @var{objfile}. The list of object files may include archives.
3510 At least one object file must be given.
3511
3512 @command{strip} modifies the files named in its argument,
3513 rather than writing modified copies under different names.
3514
3515 @c man end
3516
3517 @c man begin OPTIONS strip
3518
3519 @table @env
3520 @item -F @var{bfdname}
3521 @itemx --target=@var{bfdname}
3522 Treat the original @var{objfile} as a file with the object
3523 code format @var{bfdname}, and rewrite it in the same format.
3524 @xref{Target Selection}, for more information.
3525
3526 @item --help
3527 Show a summary of the options to @command{strip} and exit.
3528
3529 @item --info
3530 Display a list showing all architectures and object formats available.
3531
3532 @item -I @var{bfdname}
3533 @itemx --input-target=@var{bfdname}
3534 Treat the original @var{objfile} as a file with the object
3535 code format @var{bfdname}.
3536 @xref{Target Selection}, for more information.
3537
3538 @item -O @var{bfdname}
3539 @itemx --output-target=@var{bfdname}
3540 Replace @var{objfile} with a file in the output format @var{bfdname}.
3541 @xref{Target Selection}, for more information.
3542
3543 @item -R @var{sectionname}
3544 @itemx --remove-section=@var{sectionname}
3545 Remove any section named @var{sectionname} from the output file, in
3546 addition to whatever sections would otherwise be removed. This
3547 option may be given more than once. Note that using this option
3548 inappropriately may make the output file unusable. The wildcard
3549 character @samp{*} may be given at the end of @var{sectionname}. If
3550 so, then any section starting with @var{sectionname} will be removed.
3551
3552 If the first character of @var{sectionpattern} is the exclamation
3553 point (!) then matching sections will not be removed even if an
3554 earlier use of @option{--remove-section} on the same command line
3555 would otherwise remove it. For example:
3556
3557 @smallexample
3558 --remove-section=.text.* --remove-section=!.text.foo
3559 @end smallexample
3560
3561 will remove all sections matching the pattern '.text.*', but will not
3562 remove the section '.text.foo'.
3563
3564 @item --keep-section=@var{sectionpattern}
3565 When removing sections from the output file, keep sections that match
3566 @var{sectionpattern}.
3567
3568 @item --remove-relocations=@var{sectionpattern}
3569 Remove relocations from the output file for any section matching
3570 @var{sectionpattern}. This option may be given more than once. Note
3571 that using this option inappropriately may make the output file
3572 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3573 For example:
3574
3575 @smallexample
3576 --remove-relocations=.text.*
3577 @end smallexample
3578
3579 will remove the relocations for all sections matching the patter
3580 '.text.*'.
3581
3582 If the first character of @var{sectionpattern} is the exclamation
3583 point (!) then matching sections will not have their relocation
3584 removed even if an earlier use of @option{--remove-relocations} on the
3585 same command line would otherwise cause the relocations to be removed.
3586 For example:
3587
3588 @smallexample
3589 --remove-relocations=.text.* --remove-relocations=!.text.foo
3590 @end smallexample
3591
3592 will remove all relocations for sections matching the pattern
3593 '.text.*', but will not remove relocations for the section
3594 '.text.foo'.
3595
3596 @item --strip-section-headers
3597 Strip section headers. This option is specific to ELF files. Implies
3598 @option{--strip-all} and @option{--merge-notes}.
3599
3600 @item -s
3601 @itemx --strip-all
3602 Remove all symbols.
3603
3604 @item -g
3605 @itemx -S
3606 @itemx -d
3607 @itemx --strip-debug
3608 Remove debugging symbols only.
3609
3610 @item --strip-dwo
3611 Remove the contents of all DWARF .dwo sections, leaving the
3612 remaining debugging sections and all symbols intact.
3613 See the description of this option in the @command{objcopy} section
3614 for more information.
3615
3616 @item --strip-unneeded
3617 Remove all symbols that are not needed for relocation processing in
3618 addition to debugging symbols and sections stripped by
3619 @option{--strip-debug}.
3620
3621 @item -K @var{symbolname}
3622 @itemx --keep-symbol=@var{symbolname}
3623 When stripping symbols, keep symbol @var{symbolname} even if it would
3624 normally be stripped. This option may be given more than once.
3625
3626 @item -M
3627 @itemx --merge-notes
3628 @itemx --no-merge-notes
3629 For ELF files, attempt (or do not attempt) to reduce the size of any
3630 SHT_NOTE type sections by removing duplicate notes. The default is to
3631 attempt this reduction unless stripping debug or DWO information.
3632
3633 @item -N @var{symbolname}
3634 @itemx --strip-symbol=@var{symbolname}
3635 Remove symbol @var{symbolname} from the source file. This option may be
3636 given more than once, and may be combined with strip options other than
3637 @option{-K}.
3638
3639 @item -o @var{file}
3640 Put the stripped output in @var{file}, rather than replacing the
3641 existing file. When this argument is used, only one @var{objfile}
3642 argument may be specified.
3643
3644 @item -p
3645 @itemx --preserve-dates
3646 Preserve the access and modification dates of the file.
3647
3648 @item -D
3649 @itemx --enable-deterministic-archives
3650 @cindex deterministic archives
3651 @kindex --enable-deterministic-archives
3652 Operate in @emph{deterministic} mode. When copying archive members
3653 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3654 and use consistent file modes for all files.
3655
3656 If @file{binutils} was configured with
3657 @option{--enable-deterministic-archives}, then this mode is on by default.
3658 It can be disabled with the @samp{-U} option, below.
3659
3660 @item -U
3661 @itemx --disable-deterministic-archives
3662 @cindex deterministic archives
3663 @kindex --enable-deterministic-archives
3664 Do @emph{not} operate in @emph{deterministic} mode. This is the
3665 inverse of the @option{-D} option, above: when copying archive members
3666 and writing the archive index, use their actual UID, GID, timestamp,
3667 and file mode values.
3668
3669 This is the default unless @file{binutils} was configured with
3670 @option{--enable-deterministic-archives}.
3671
3672 @item -w
3673 @itemx --wildcard
3674 Permit regular expressions in @var{symbolname}s used in other command
3675 line options. The question mark (?), asterisk (*), backslash (\) and
3676 square brackets ([]) operators can be used anywhere in the symbol
3677 name. If the first character of the symbol name is the exclamation
3678 point (!) then the sense of the switch is reversed for that symbol.
3679 For example:
3680
3681 @smallexample
3682 -w -K !foo -K fo*
3683 @end smallexample
3684
3685 would cause strip to only keep symbols that start with the letters
3686 ``fo'', but to discard the symbol ``foo''.
3687
3688 @item -x
3689 @itemx --discard-all
3690 Remove non-global symbols.
3691
3692 @item -X
3693 @itemx --discard-locals
3694 Remove compiler-generated local symbols.
3695 (These usually start with @samp{L} or @samp{.}.)
3696
3697 @item --keep-section-symbols
3698 When stripping a file, perhaps with @option{--strip-debug} or
3699 @option{--strip-unneeded}, retain any symbols specifying section names,
3700 which would otherwise get stripped.
3701
3702 @item --keep-file-symbols
3703 When stripping a file, perhaps with @option{--strip-debug} or
3704 @option{--strip-unneeded}, retain any symbols specifying source file names,
3705 which would otherwise get stripped.
3706
3707 @item --only-keep-debug
3708 Strip a file, emptying the contents of any sections that would not be
3709 stripped by @option{--strip-debug} and leaving the debugging sections
3710 intact. In ELF files, this preserves all the note sections in the
3711 output as well.
3712
3713 Note - the section headers of the stripped sections are preserved,
3714 including their sizes, but the contents of the section are discarded.
3715 The section headers are preserved so that other tools can match up the
3716 debuginfo file with the real executable, even if that executable has
3717 been relocated to a different address space.
3718
3719 The intention is that this option will be used in conjunction with
3720 @option{--add-gnu-debuglink} to create a two part executable. One a
3721 stripped binary which will occupy less space in RAM and in a
3722 distribution and the second a debugging information file which is only
3723 needed if debugging abilities are required. The suggested procedure
3724 to create these files is as follows:
3725
3726 @enumerate
3727 @item Link the executable as normal. Assuming that it is called
3728 @code{foo} then...
3729 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3730 create a file containing the debugging info.
3731 @item Run @code{objcopy --strip-debug foo} to create a
3732 stripped executable.
3733 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3734 to add a link to the debugging info into the stripped executable.
3735 @end enumerate
3736
3737 Note---the choice of @code{.dbg} as an extension for the debug info
3738 file is arbitrary. Also the @code{--only-keep-debug} step is
3739 optional. You could instead do this:
3740
3741 @enumerate
3742 @item Link the executable as normal.
3743 @item Copy @code{foo} to @code{foo.full}
3744 @item Run @code{strip --strip-debug foo}
3745 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3746 @end enumerate
3747
3748 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3749 full executable. It does not have to be a file created by the
3750 @option{--only-keep-debug} switch.
3751
3752 Note---this switch is only intended for use on fully linked files. It
3753 does not make sense to use it on object files where the debugging
3754 information may be incomplete. Besides the gnu_debuglink feature
3755 currently only supports the presence of one filename containing
3756 debugging information, not multiple filenames on a one-per-object-file
3757 basis.
3758
3759 @item -V
3760 @itemx --version
3761 Show the version number for @command{strip}.
3762
3763 @item -v
3764 @itemx --verbose
3765 Verbose output: list all object files modified. In the case of
3766 archives, @samp{strip -v} lists all members of the archive.
3767 @end table
3768
3769 @c man end
3770
3771 @ignore
3772 @c man begin SEEALSO strip
3773 the Info entries for @file{binutils}.
3774 @c man end
3775 @end ignore
3776
3777 @node c++filt, addr2line, strip, Top
3778 @chapter c++filt
3779
3780 @kindex c++filt
3781 @cindex demangling C++ symbols
3782
3783 @c man title cxxfilt demangle C++ and Java symbols
3784
3785 @smallexample
3786 @c man begin SYNOPSIS cxxfilt
3787 c++filt [@option{-_}|@option{--strip-underscore}]
3788 [@option{-n}|@option{--no-strip-underscore}]
3789 [@option{-p}|@option{--no-params}]
3790 [@option{-t}|@option{--types}]
3791 [@option{-i}|@option{--no-verbose}]
3792 [@option{-r}|@option{--no-recurse-limit}]
3793 [@option{-R}|@option{--recurse-limit}]
3794 [@option{-s} @var{format}|@option{--format=}@var{format}]
3795 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3796 @c man end
3797 @end smallexample
3798
3799 @c man begin DESCRIPTION cxxfilt
3800
3801 @kindex cxxfilt
3802 The C++ and Java languages provide function overloading, which means
3803 that you can write many functions with the same name, providing that
3804 each function takes parameters of different types. In order to be
3805 able to distinguish these similarly named functions C++ and Java
3806 encode them into a low-level assembler name which uniquely identifies
3807 each different version. This process is known as @dfn{mangling}. The
3808 @command{c++filt}
3809 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3810 MS-DOS this program is named @command{CXXFILT}.}
3811 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3812 names into user-level names so that they can be read.
3813
3814 Every alphanumeric word (consisting of letters, digits, underscores,
3815 dollars, or periods) seen in the input is a potential mangled name.
3816 If the name decodes into a C++ name, the C++ name replaces the
3817 low-level name in the output, otherwise the original word is output.
3818 In this way you can pass an entire assembler source file, containing
3819 mangled names, through @command{c++filt} and see the same source file
3820 containing demangled names.
3821
3822 You can also use @command{c++filt} to decipher individual symbols by
3823 passing them on the command line:
3824
3825 @example
3826 c++filt @var{symbol}
3827 @end example
3828
3829 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3830 names from the standard input instead. All the results are printed on
3831 the standard output. The difference between reading names from the
3832 command line versus reading names from the standard input is that
3833 command-line arguments are expected to be just mangled names and no
3834 checking is performed to separate them from surrounding text. Thus
3835 for example:
3836
3837 @smallexample
3838 c++filt -n _Z1fv
3839 @end smallexample
3840
3841 will work and demangle the name to ``f()'' whereas:
3842
3843 @smallexample
3844 c++filt -n _Z1fv,
3845 @end smallexample
3846
3847 will not work. (Note the extra comma at the end of the mangled
3848 name which makes it invalid). This command however will work:
3849
3850 @smallexample
3851 echo _Z1fv, | c++filt -n
3852 @end smallexample
3853
3854 and will display ``f(),'', i.e., the demangled name followed by a
3855 trailing comma. This behaviour is because when the names are read
3856 from the standard input it is expected that they might be part of an
3857 assembler source file where there might be extra, extraneous
3858 characters trailing after a mangled name. For example:
3859
3860 @smallexample
3861 .type _Z1fv, @@function
3862 @end smallexample
3863
3864 @c man end
3865
3866 @c man begin OPTIONS cxxfilt
3867
3868 @table @env
3869 @item -_
3870 @itemx --strip-underscore
3871 On some systems, both the C and C++ compilers put an underscore in front
3872 of every name. For example, the C name @code{foo} gets the low-level
3873 name @code{_foo}. This option removes the initial underscore. Whether
3874 @command{c++filt} removes the underscore by default is target dependent.
3875
3876 @item -n
3877 @itemx --no-strip-underscore
3878 Do not remove the initial underscore.
3879
3880 @item -p
3881 @itemx --no-params
3882 When demangling the name of a function, do not display the types of
3883 the function's parameters.
3884
3885 @item -t
3886 @itemx --types
3887 Attempt to demangle types as well as function names. This is disabled
3888 by default since mangled types are normally only used internally in
3889 the compiler, and they can be confused with non-mangled names. For example,
3890 a function called ``a'' treated as a mangled type name would be
3891 demangled to ``signed char''.
3892
3893 @item -i
3894 @itemx --no-verbose
3895 Do not include implementation details (if any) in the demangled
3896 output.
3897
3898 @item -r
3899 @itemx -R
3900 @itemx --recurse-limit
3901 @itemx --no-recurse-limit
3902 @itemx --recursion-limit
3903 @itemx --no-recursion-limit
3904 Enables or disables a limit on the amount of recursion performed
3905 whilst demangling strings. Since the name mangling formats allow for
3906 an infinite level of recursion it is possible to create strings whose
3907 decoding will exhaust the amount of stack space available on the host
3908 machine, triggering a memory fault. The limit tries to prevent this
3909 from happening by restricting recursion to 2048 levels of nesting.
3910
3911 The default is for this limit to be enabled, but disabling it may be
3912 necessary in order to demangle truly complicated names. Note however
3913 that if the recursion limit is disabled then stack exhaustion is
3914 possible and any bug reports about such an event will be rejected.
3915
3916 The @option{-r} option is a synonym for the
3917 @option{--no-recurse-limit} option. The @option{-R} option is a
3918 synonym for the @option{--recurse-limit} option.
3919
3920 @item -s @var{format}
3921 @itemx --format=@var{format}
3922 @command{c++filt} can decode various methods of mangling, used by
3923 different compilers. The argument to this option selects which
3924 method it uses:
3925
3926 @table @code
3927 @item auto
3928 Automatic selection based on executable (the default method)
3929 @item gnu
3930 the one used by the @sc{gnu} C++ compiler (g++)
3931 @item lucid
3932 the one used by the Lucid compiler (lcc)
3933 @item arm
3934 the one specified by the C++ Annotated Reference Manual
3935 @item hp
3936 the one used by the HP compiler (aCC)
3937 @item edg
3938 the one used by the EDG compiler
3939 @item gnu-v3
3940 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3941 @item java
3942 the one used by the @sc{gnu} Java compiler (gcj)
3943 @item gnat
3944 the one used by the @sc{gnu} Ada compiler (GNAT).
3945 @end table
3946
3947 @item --help
3948 Print a summary of the options to @command{c++filt} and exit.
3949
3950 @item --version
3951 Print the version number of @command{c++filt} and exit.
3952 @end table
3953
3954 @c man end
3955
3956 @ignore
3957 @c man begin SEEALSO cxxfilt
3958 the Info entries for @file{binutils}.
3959 @c man end
3960 @end ignore
3961
3962 @quotation
3963 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3964 user interface are subject to change in future releases. In particular,
3965 a command-line option may be required in the future to decode a name
3966 passed as an argument on the command line; in other words,
3967
3968 @example
3969 c++filt @var{symbol}
3970 @end example
3971
3972 @noindent
3973 may in a future release become
3974
3975 @example
3976 c++filt @var{option} @var{symbol}
3977 @end example
3978 @end quotation
3979
3980 @node addr2line
3981 @chapter addr2line
3982
3983 @kindex addr2line
3984 @cindex address to file name and line number
3985
3986 @c man title addr2line convert addresses or symbol+offset into file names and line numbers
3987
3988 @smallexample
3989 @c man begin SYNOPSIS addr2line
3990 addr2line [@option{-a}|@option{--addresses}]
3991 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3992 [@option{-C}|@option{--demangle}[=@var{style}]]
3993 [@option{-r}|@option{--no-recurse-limit}]
3994 [@option{-R}|@option{--recurse-limit}]
3995 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3996 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3997 [@option{-i}|@option{--inlines}]
3998 [@option{-p}|@option{--pretty-print}]
3999 [@option{-j}|@option{--section=}@var{name}]
4000 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
4001 [addr addr @dots{}]
4002 @c man end
4003 @end smallexample
4004
4005 @c man begin DESCRIPTION addr2line
4006
4007 @command{addr2line} translates addresses or symbol+offset into file names and line numbers.
4008 Given an address or symbol+offset in an executable or an offset in a section of a relocatable
4009 object, it uses the debugging information to figure out which file name and
4010 line number are associated with it.
4011
4012 The executable or relocatable object to use is specified with the @option{-e}
4013 option. The default is the file @file{a.out}. The section in the relocatable
4014 object to use is specified with the @option{-j} option.
4015
4016 @command{addr2line} has two modes of operation.
4017
4018 In the first, hexadecimal addresses or symbol+offset are specified on the command line,
4019 and @command{addr2line} displays the file name and line number for each
4020 address.
4021
4022 In the second, @command{addr2line} reads hexadecimal addresses or symbol+offset from
4023 standard input, and prints the file name and line number for each
4024 address on standard output. In this mode, @command{addr2line} may be used
4025 in a pipe to convert dynamically chosen addresses.
4026
4027 The format of the output is @samp{FILENAME:LINENO}. By default
4028 each input address generates one line of output.
4029
4030 Two options can generate additional lines before each
4031 @samp{FILENAME:LINENO} line (in that order).
4032
4033 If the @option{-a} option is used then a line with the input address
4034 is displayed.
4035
4036 If the @option{-f} option is used, then a line with the
4037 @samp{FUNCTIONNAME} is displayed. This is the name of the function
4038 containing the address.
4039
4040 One option can generate additional lines after the
4041 @samp{FILENAME:LINENO} line.
4042
4043 If the @option{-i} option is used and the code at the given address is
4044 present there because of inlining by the compiler then additional
4045 lines are displayed afterwards. One or two extra lines (if the
4046 @option{-f} option is used) are displayed for each inlined function.
4047
4048 Alternatively if the @option{-p} option is used then each input
4049 address generates a single, long, output line containing the address,
4050 the function name, the file name and the line number. If the
4051 @option{-i} option has also been used then any inlined functions will
4052 be displayed in the same manner, but on separate lines, and prefixed
4053 by the text @samp{(inlined by)}.
4054
4055 If the file name or function name can not be determined,
4056 @command{addr2line} will print two question marks in their place. If the
4057 line number can not be determined, @command{addr2line} will print 0.
4058
4059 When symbol+offset is used, +offset is optional, except when the symbol
4060 is ambigious with a hex number. The resolved symbols can be mangled
4061 or unmangled, except unmangled symbols with + are not allowed.
4062
4063 @c man end
4064
4065 @c man begin OPTIONS addr2line
4066
4067 The long and short forms of options, shown here as alternatives, are
4068 equivalent.
4069
4070 @table @env
4071 @item -a
4072 @itemx --addresses
4073 Display the address before the function name, file and line number
4074 information. The address is printed with a @samp{0x} prefix to easily
4075 identify it.
4076
4077 @item -b @var{bfdname}
4078 @itemx --target=@var{bfdname}
4079 @cindex object code format
4080 Specify that the object-code format for the object files is
4081 @var{bfdname}.
4082
4083 @item -C
4084 @itemx --demangle[=@var{style}]
4085 @cindex demangling in objdump
4086 Decode (@dfn{demangle}) low-level symbol names into user-level names.
4087 Besides removing any initial underscore prepended by the system, this
4088 makes C++ function names readable. Different compilers have different
4089 mangling styles. The optional demangling style argument can be used to
4090 choose an appropriate demangling style for your compiler. @xref{c++filt},
4091 for more information on demangling.
4092
4093 @item -e @var{filename}
4094 @itemx --exe=@var{filename}
4095 Specify the name of the executable for which addresses should be
4096 translated. The default file is @file{a.out}.
4097
4098 @item -f
4099 @itemx --functions
4100 Display function names as well as file and line number information.
4101
4102 @item -s
4103 @itemx --basenames
4104 Display only the base of each file name.
4105
4106 @item -i
4107 @itemx --inlines
4108 If the address belongs to a function that was inlined, the source
4109 information for all enclosing scopes back to the first non-inlined
4110 function will also be printed. For example, if @code{main} inlines
4111 @code{callee1} which inlines @code{callee2}, and address is from
4112 @code{callee2}, the source information for @code{callee1} and @code{main}
4113 will also be printed.
4114
4115 @item -j
4116 @itemx --section
4117 Read offsets relative to the specified section instead of absolute addresses.
4118
4119 @item -p
4120 @itemx --pretty-print
4121 Make the output more human friendly: each location are printed on one line.
4122 If option @option{-i} is specified, lines for all enclosing scopes are
4123 prefixed with @samp{(inlined by)}.
4124
4125 @item -r
4126 @itemx -R
4127 @itemx --recurse-limit
4128 @itemx --no-recurse-limit
4129 @itemx --recursion-limit
4130 @itemx --no-recursion-limit
4131 Enables or disables a limit on the amount of recursion performed
4132 whilst demangling strings. Since the name mangling formats allow for
4133 an infinite level of recursion it is possible to create strings whose
4134 decoding will exhaust the amount of stack space available on the host
4135 machine, triggering a memory fault. The limit tries to prevent this
4136 from happening by restricting recursion to 2048 levels of nesting.
4137
4138 The default is for this limit to be enabled, but disabling it may be
4139 necessary in order to demangle truly complicated names. Note however
4140 that if the recursion limit is disabled then stack exhaustion is
4141 possible and any bug reports about such an event will be rejected.
4142
4143 The @option{-r} option is a synonym for the
4144 @option{--no-recurse-limit} option. The @option{-R} option is a
4145 synonym for the @option{--recurse-limit} option.
4146
4147 Note this option is only effective if the @option{-C} or
4148 @option{--demangle} option has been enabled.
4149
4150 @end table
4151
4152 @c man end
4153
4154 @ignore
4155 @c man begin SEEALSO addr2line
4156 Info entries for @file{binutils}.
4157 @c man end
4158 @end ignore
4159
4160 @node windmc
4161 @chapter windmc
4162
4163 @command{windmc} may be used to generator Windows message resources.
4164
4165 @quotation
4166 @emph{Warning:} @command{windmc} is not always built as part of the binary
4167 utilities, since it is only useful for Windows targets.
4168 @end quotation
4169
4170 @c man title windmc generates Windows message resources
4171
4172 @smallexample
4173 @c man begin SYNOPSIS windmc
4174 windmc [options] input-file
4175 @c man end
4176 @end smallexample
4177
4178 @c man begin DESCRIPTION windmc
4179
4180 @command{windmc} reads message definitions from an input file (.mc) and
4181 translate them into a set of output files. The output files may be of
4182 four kinds:
4183
4184 @table @code
4185 @item h
4186 A C header file containing the message definitions.
4187
4188 @item rc
4189 A resource file compilable by the @command{windres} tool.
4190
4191 @item bin
4192 One or more binary files containing the resource data for a specific
4193 message language.
4194
4195 @item dbg
4196 A C include file that maps message id's to their symbolic name.
4197 @end table
4198
4199 The exact description of these different formats is available in
4200 documentation from Microsoft.
4201
4202 When @command{windmc} converts from the @code{mc} format to the @code{bin}
4203 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
4204 Windows Message Compiler.
4205
4206 @c man end
4207
4208 @c man begin OPTIONS windmc
4209
4210 @table @env
4211 @item -a
4212 @itemx --ascii_in
4213 Specifies that the input file specified is ASCII. This is the default
4214 behaviour.
4215
4216 @item -A
4217 @itemx --ascii_out
4218 Specifies that messages in the output @code{bin} files should be in ASCII
4219 format.
4220
4221 @item -b
4222 @itemx --binprefix
4223 Specifies that @code{bin} filenames should have to be prefixed by the
4224 basename of the source file.
4225
4226 @item -c
4227 @itemx --customflag
4228 Sets the customer bit in all message id's.
4229
4230 @item -C @var{codepage}
4231 @itemx --codepage_in @var{codepage}
4232 Sets the default codepage to be used to convert input file to UTF16. The
4233 default is ocdepage 1252.
4234
4235 @item -d
4236 @itemx --decimal_values
4237 Outputs the constants in the header file in decimal. Default is using
4238 hexadecimal output.
4239
4240 @item -e @var{ext}
4241 @itemx --extension @var{ext}
4242 The extension for the header file. The default is .h extension.
4243
4244 @item -F @var{target}
4245 @itemx --target @var{target}
4246 Specify the BFD format to use for a bin file as output. This
4247 is a BFD target name; you can use the @option{--help} option to see a list
4248 of supported targets. Normally @command{windmc} will use the default
4249 format, which is the first one listed by the @option{--help} option.
4250 @ifclear man
4251 @ref{Target Selection}.
4252 @end ifclear
4253
4254 @item -h @var{path}
4255 @itemx --headerdir @var{path}
4256 The target directory of the generated header file. The default is the
4257 current directory.
4258
4259 @item -H
4260 @itemx --help
4261 Displays a list of command-line options and then exits.
4262
4263 @item -m @var{characters}
4264 @itemx --maxlength @var{characters}
4265 Instructs @command{windmc} to generate a warning if the length
4266 of any message exceeds the number specified.
4267
4268 @item -n
4269 @itemx --nullterminate
4270 Terminate message text in @code{bin} files by zero. By default they are
4271 terminated by CR/LF.
4272
4273 @item -o
4274 @itemx --hresult_use
4275 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4276 file, using HRESULT definitions. Status codes are used if the flag is not
4277 specified.
4278
4279 @item -O @var{codepage}
4280 @itemx --codepage_out @var{codepage}
4281 Sets the default codepage to be used to output text files. The default
4282 is ocdepage 1252.
4283
4284 @item -r @var{path}
4285 @itemx --rcdir @var{path}
4286 The target directory for the generated @code{rc} script and the generated
4287 @code{bin} files that the resource compiler script includes. The default
4288 is the current directory.
4289
4290 @item -u
4291 @itemx --unicode_in
4292 Specifies that the input file is UTF16.
4293
4294 @item -U
4295 @itemx --unicode_out
4296 Specifies that messages in the output @code{bin} file should be in UTF16
4297 format. This is the default behaviour.
4298
4299 @item -v
4300 @item --verbose
4301 Enable verbose mode.
4302
4303 @item -V
4304 @item --version
4305 Prints the version number for @command{windmc}.
4306
4307 @item -x @var{path}
4308 @itemx --xdgb @var{path}
4309 The path of the @code{dbg} C include file that maps message id's to the
4310 symbolic name. No such file is generated without specifying the switch.
4311 @end table
4312
4313 @c man end
4314
4315 @ignore
4316 @c man begin SEEALSO windmc
4317 the Info entries for @file{binutils}.
4318 @c man end
4319 @end ignore
4320
4321 @node windres
4322 @chapter windres
4323
4324 @command{windres} may be used to manipulate Windows resources.
4325
4326 @quotation
4327 @emph{Warning:} @command{windres} is not always built as part of the binary
4328 utilities, since it is only useful for Windows targets.
4329 @end quotation
4330
4331 @c man title windres manipulate Windows resources
4332
4333 @smallexample
4334 @c man begin SYNOPSIS windres
4335 windres [options] [input-file] [output-file]
4336 @c man end
4337 @end smallexample
4338
4339 @c man begin DESCRIPTION windres
4340
4341 @command{windres} reads resources from an input file and copies them into
4342 an output file. Either file may be in one of three formats:
4343
4344 @table @code
4345 @item rc
4346 A text format read by the Resource Compiler.
4347
4348 @item res
4349 A binary format generated by the Resource Compiler.
4350
4351 @item coff
4352 A COFF object or executable.
4353 @end table
4354
4355 The exact description of these different formats is available in
4356 documentation from Microsoft.
4357
4358 When @command{windres} converts from the @code{rc} format to the @code{res}
4359 format, it is acting like the Windows Resource Compiler. When
4360 @command{windres} converts from the @code{res} format to the @code{coff}
4361 format, it is acting like the Windows @code{CVTRES} program.
4362
4363 When @command{windres} generates an @code{rc} file, the output is similar
4364 but not identical to the format expected for the input. When an input
4365 @code{rc} file refers to an external filename, an output @code{rc} file
4366 will instead include the file contents.
4367
4368 If the input or output format is not specified, @command{windres} will
4369 guess based on the file name, or, for the input file, the file contents.
4370 A file with an extension of @file{.rc} will be treated as an @code{rc}
4371 file, a file with an extension of @file{.res} will be treated as a
4372 @code{res} file, and a file with an extension of @file{.o} or
4373 @file{.exe} will be treated as a @code{coff} file.
4374
4375 If no output file is specified, @command{windres} will print the resources
4376 in @code{rc} format to standard output.
4377
4378 The normal use is for you to write an @code{rc} file, use @command{windres}
4379 to convert it to a COFF object file, and then link the COFF file into
4380 your application. This will make the resources described in the
4381 @code{rc} file available to Windows.
4382
4383 @c man end
4384
4385 @c man begin OPTIONS windres
4386
4387 @table @env
4388 @item -i @var{filename}
4389 @itemx --input @var{filename}
4390 The name of the input file. If this option is not used, then
4391 @command{windres} will use the first non-option argument as the input file
4392 name. If there are no non-option arguments, then @command{windres} will
4393 read from standard input. @command{windres} can not read a COFF file from
4394 standard input.
4395
4396 @item -o @var{filename}
4397 @itemx --output @var{filename}
4398 The name of the output file. If this option is not used, then
4399 @command{windres} will use the first non-option argument, after any used
4400 for the input file name, as the output file name. If there is no
4401 non-option argument, then @command{windres} will write to standard output.
4402 @command{windres} can not write a COFF file to standard output. Note,
4403 for compatibility with @command{rc} the option @option{-fo} is also
4404 accepted, but its use is not recommended.
4405
4406 @item -J @var{format}
4407 @itemx --input-format @var{format}
4408 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4409 @samp{coff}. If no input format is specified, @command{windres} will
4410 guess, as described above.
4411
4412 @item -O @var{format}
4413 @itemx --output-format @var{format}
4414 The output format to generate. @var{format} may be @samp{res},
4415 @samp{rc}, or @samp{coff}. If no output format is specified,
4416 @command{windres} will guess, as described above.
4417
4418 @item -F @var{target}
4419 @itemx --target @var{target}
4420 Specify the BFD format to use for a COFF file as input or output. This
4421 is a BFD target name; you can use the @option{--help} option to see a list
4422 of supported targets. Normally @command{windres} will use the default
4423 format, which is the first one listed by the @option{--help} option.
4424 @ifclear man
4425 @ref{Target Selection}.
4426 @end ifclear
4427
4428 @item --preprocessor @var{program}
4429 When @command{windres} reads an @code{rc} file, it runs it through the C
4430 preprocessor first. This option may be used to specify the preprocessor
4431 to use. The default preprocessor is @code{gcc}.
4432
4433 @item --preprocessor-arg @var{option}
4434 When @command{windres} reads an @code{rc} file, it runs it through
4435 the C preprocessor first. This option may be used to specify additional
4436 text to be passed to preprocessor on its command line.
4437 This option can be used multiple times to add multiple options to the
4438 preprocessor command line.
4439 If the @option{--preprocessor} option has not been specified then a
4440 default set of preprocessor arguments will be used, with any
4441 @option{--preprocessor-arg} options being placed after them on the
4442 command line. These default arguments are @code{-E},
4443 @code{-xc-header} and @code{-DRC_INVOKED}.
4444
4445 @item -I @var{directory}
4446 @itemx --include-dir @var{directory}
4447 Specify an include directory to use when reading an @code{rc} file.
4448 @command{windres} will pass this to the preprocessor as an @option{-I}
4449 option. @command{windres} will also search this directory when looking for
4450 files named in the @code{rc} file. If the argument passed to this command
4451 matches any of the supported @var{formats} (as described in the @option{-J}
4452 option), it will issue a deprecation warning, and behave just like the
4453 @option{-J} option. New programs should not use this behaviour. If a
4454 directory happens to match a @var{format}, simple prefix it with @samp{./}
4455 to disable the backward compatibility.
4456
4457 @item -D @var{target}
4458 @itemx --define @var{sym}[=@var{val}]
4459 Specify a @option{-D} option to pass to the preprocessor when reading an
4460 @code{rc} file.
4461
4462 @item -U @var{target}
4463 @itemx --undefine @var{sym}
4464 Specify a @option{-U} option to pass to the preprocessor when reading an
4465 @code{rc} file.
4466
4467 @item -r
4468 Ignored for compatibility with rc.
4469
4470 @item -v
4471 Enable verbose mode. This tells you what the preprocessor is if you
4472 didn't specify one.
4473
4474 @item -c @var{val}
4475 @item --codepage @var{val}
4476 Specify the default codepage to use when reading an @code{rc} file.
4477 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4478 codepage code. The valid range is from zero up to 0xffff, but the
4479 validity of the codepage is host and configuration dependent.
4480
4481 @item -l @var{val}
4482 @item --language @var{val}
4483 Specify the default language to use when reading an @code{rc} file.
4484 @var{val} should be a hexadecimal language code. The low eight bits are
4485 the language, and the high eight bits are the sublanguage.
4486
4487 @item --use-temp-file
4488 Use a temporary file to instead of using popen to read the output of
4489 the preprocessor. Use this option if the popen implementation is buggy
4490 on the host (eg., certain non-English language versions of Windows 95 and
4491 Windows 98 are known to have buggy popen where the output will instead
4492 go the console).
4493
4494 @item --no-use-temp-file
4495 Use popen, not a temporary file, to read the output of the preprocessor.
4496 This is the default behaviour.
4497
4498 @item -h
4499 @item --help
4500 Prints a usage summary.
4501
4502 @item -V
4503 @item --version
4504 Prints the version number for @command{windres}.
4505
4506 @item --yydebug
4507 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4508 this will turn on parser debugging.
4509 @end table
4510
4511 @c man end
4512
4513 @ignore
4514 @c man begin SEEALSO windres
4515 the Info entries for @file{binutils}.
4516 @c man end
4517 @end ignore
4518
4519 @node dlltool
4520 @chapter dlltool
4521 @cindex DLL
4522 @kindex dlltool
4523
4524 @command{dlltool} is used to create the files needed to create dynamic
4525 link libraries (DLLs) on systems which understand PE format image
4526 files such as Windows. A DLL contains an export table which contains
4527 information that the runtime loader needs to resolve references from a
4528 referencing program.
4529
4530 The export table is generated by this program by reading in a
4531 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4532 will be in the DLL. A @file{.o} file can contain information in
4533 special @samp{.drectve} sections with export information.
4534
4535 @quotation
4536 @emph{Note:} @command{dlltool} is not always built as part of the
4537 binary utilities, since it is only useful for those targets which
4538 support DLLs.
4539 @end quotation
4540
4541 @c man title dlltool create files needed to build and use DLLs
4542
4543 @smallexample
4544 @c man begin SYNOPSIS dlltool
4545 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4546 [@option{-b}|@option{--base-file} @var{base-file-name}]
4547 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4548 [@option{-z}|@option{--output-def} @var{def-file-name}]
4549 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4550 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4551 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4552 [@option{--exclude-symbols} @var{list}]
4553 [@option{--no-default-excludes}]
4554 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4555 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4556 [@option{-a}|@option{--add-indirect}]
4557 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4558 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4559 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4560 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4561 [@option{--use-nul-prefixed-import-tables}]
4562 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4563 [@option{-i}|@option{--interwork}]
4564 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4565 [@option{-v}|@option{--verbose}]
4566 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4567 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4568 [@option{--deterministic-libraries}] [@option{--non-deterministic-libraries}]
4569 [object-file @dots{}]
4570 @c man end
4571 @end smallexample
4572
4573 @c man begin DESCRIPTION dlltool
4574
4575 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4576 @option{-b} options as well as object files specified on the command
4577 line. It then processes these inputs and if the @option{-e} option has
4578 been specified it creates a exports file. If the @option{-l} option
4579 has been specified it creates a library file and if the @option{-z} option
4580 has been specified it creates a def file. Any or all of the @option{-e},
4581 @option{-l} and @option{-z} options can be present in one invocation of
4582 dlltool.
4583
4584 When creating a DLL, along with the source for the DLL, it is necessary
4585 to have three other files. @command{dlltool} can help with the creation of
4586 these files.
4587
4588 The first file is a @file{.def} file which specifies which functions are
4589 exported from the DLL, which functions the DLL imports, and so on. This
4590 is a text file and can be created by hand, or @command{dlltool} can be used
4591 to create it using the @option{-z} option. In this case @command{dlltool}
4592 will scan the object files specified on its command line looking for
4593 those functions which have been specially marked as being exported and
4594 put entries for them in the @file{.def} file it creates.
4595
4596 In order to mark a function as being exported from a DLL, it needs to
4597 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4598 section of the object file. This can be done in C by using the
4599 asm() operator:
4600
4601 @smallexample
4602 asm (".section .drectve");
4603 asm (".ascii \"-export:my_func\"");
4604
4605 int my_func (void) @{ @dots{} @}
4606 @end smallexample
4607
4608 The second file needed for DLL creation is an exports file. This file
4609 is linked with the object files that make up the body of the DLL and it
4610 handles the interface between the DLL and the outside world. This is a
4611 binary file and it can be created by giving the @option{-e} option to
4612 @command{dlltool} when it is creating or reading in a @file{.def} file.
4613
4614 The third file needed for DLL creation is the library file that programs
4615 will link with in order to access the functions in the DLL (an `import
4616 library'). This file can be created by giving the @option{-l} option to
4617 dlltool when it is creating or reading in a @file{.def} file.
4618
4619 If the @option{-y} option is specified, dlltool generates a delay-import
4620 library that can be used instead of the normal import library to allow
4621 a program to link to the dll only as soon as an imported function is
4622 called for the first time. The resulting executable will need to be
4623 linked to the static delayimp library containing __delayLoadHelper2(),
4624 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4625
4626 @command{dlltool} builds the library file by hand, but it builds the
4627 exports file by creating temporary files containing assembler statements
4628 and then assembling these. The @option{-S} command-line option can be
4629 used to specify the path to the assembler that dlltool will use,
4630 and the @option{-f} option can be used to pass specific flags to that
4631 assembler. The @option{-n} can be used to prevent dlltool from deleting
4632 these temporary assembler files when it is done, and if @option{-n} is
4633 specified twice then this will prevent dlltool from deleting the
4634 temporary object files it used to build the library.
4635
4636 Here is an example of creating a DLL from a source file @samp{dll.c} and
4637 also creating a program (from an object file called @samp{program.o})
4638 that uses that DLL:
4639
4640 @smallexample
4641 gcc -c dll.c
4642 dlltool -e exports.o -l dll.lib dll.o
4643 gcc dll.o exports.o -o dll.dll
4644 gcc program.o dll.lib -o program
4645 @end smallexample
4646
4647
4648 @command{dlltool} may also be used to query an existing import library
4649 to determine the name of the DLL to which it is associated. See the
4650 description of the @option{-I} or @option{--identify} option.
4651
4652 @c man end
4653
4654 @c man begin OPTIONS dlltool
4655
4656 The command-line options have the following meanings:
4657
4658 @table @env
4659
4660 @item -d @var{filename}
4661 @itemx --input-def @var{filename}
4662 @cindex input .def file
4663 Specifies the name of a @file{.def} file to be read in and processed.
4664
4665 @item -b @var{filename}
4666 @itemx --base-file @var{filename}
4667 @cindex base files
4668 Specifies the name of a base file to be read in and processed. The
4669 contents of this file will be added to the relocation section in the
4670 exports file generated by dlltool.
4671
4672 @item -e @var{filename}
4673 @itemx --output-exp @var{filename}
4674 Specifies the name of the export file to be created by dlltool.
4675
4676 @item -z @var{filename}
4677 @itemx --output-def @var{filename}
4678 Specifies the name of the @file{.def} file to be created by dlltool.
4679
4680 @item -l @var{filename}
4681 @itemx --output-lib @var{filename}
4682 Specifies the name of the library file to be created by dlltool.
4683
4684 @item -y @var{filename}
4685 @itemx --output-delaylib @var{filename}
4686 Specifies the name of the delay-import library file to be created by dlltool.
4687
4688 @item --deterministic-libraries
4689 @itemx --non-deterministic-libraries
4690 When creating output libraries in response to either the
4691 @option{--output-lib} or @option{--output-delaylib} options either use
4692 the value of zero for any timestamps, user ids and group ids created
4693 (@option{--deterministic-libraries}) or the actual timestamps, user
4694 ids and group ids (@option{--non-deterministic-libraries}).
4695
4696 @item --export-all-symbols
4697 Treat all global and weak defined symbols found in the input object
4698 files as symbols to be exported. There is a small list of symbols which
4699 are not exported by default; see the @option{--no-default-excludes}
4700 option. You may add to the list of symbols to not export by using the
4701 @option{--exclude-symbols} option.
4702
4703 @item --no-export-all-symbols
4704 Only export symbols explicitly listed in an input @file{.def} file or in
4705 @samp{.drectve} sections in the input object files. This is the default
4706 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4707 attributes in the source code.
4708
4709 @item --exclude-symbols @var{list}
4710 Do not export the symbols in @var{list}. This is a list of symbol names
4711 separated by comma or colon characters. The symbol names should not
4712 contain a leading underscore. This is only meaningful when
4713 @option{--export-all-symbols} is used.
4714
4715 @item --no-default-excludes
4716 When @option{--export-all-symbols} is used, it will by default avoid
4717 exporting certain special symbols. The current list of symbols to avoid
4718 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4719 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4720 to go ahead and export these special symbols. This is only meaningful
4721 when @option{--export-all-symbols} is used.
4722
4723 @item -S @var{path}
4724 @itemx --as @var{path}
4725 Specifies the path, including the filename, of the assembler to be used
4726 to create the exports file.
4727
4728 @item -f @var{options}
4729 @itemx --as-flags @var{options}
4730 Specifies any specific command-line options to be passed to the
4731 assembler when building the exports file. This option will work even if
4732 the @option{-S} option is not used. This option only takes one argument,
4733 and if it occurs more than once on the command line, then later
4734 occurrences will override earlier occurrences. So if it is necessary to
4735 pass multiple options to the assembler they should be enclosed in
4736 double quotes.
4737
4738 @item -D @var{name}
4739 @itemx --dll-name @var{name}
4740 Specifies the name to be stored in the @file{.def} file as the name of
4741 the DLL when the @option{-e} option is used. If this option is not
4742 present, then the filename given to the @option{-e} option will be
4743 used as the name of the DLL.
4744
4745 @item -m @var{machine}
4746 @itemx -machine @var{machine}
4747 Specifies the type of machine for which the library file should be
4748 built. @command{dlltool} has a built in default type, depending upon how
4749 it was created, but this option can be used to override that. This is
4750 normally only useful when creating DLLs for an ARM processor, when the
4751 contents of the DLL are actually encode using Thumb instructions.
4752
4753 @item -a
4754 @itemx --add-indirect
4755 Specifies that when @command{dlltool} is creating the exports file it
4756 should add a section which allows the exported functions to be
4757 referenced without using the import library. Whatever the hell that
4758 means!
4759
4760 @item -U
4761 @itemx --add-underscore
4762 Specifies that when @command{dlltool} is creating the exports file it
4763 should prepend an underscore to the names of @emph{all} exported symbols.
4764
4765 @item --no-leading-underscore
4766 @item --leading-underscore
4767 Specifies whether standard symbol should be forced to be prefixed, or
4768 not.
4769
4770 @item --add-stdcall-underscore
4771 Specifies that when @command{dlltool} is creating the exports file it
4772 should prepend an underscore to the names of exported @emph{stdcall}
4773 functions. Variable names and non-stdcall function names are not modified.
4774 This option is useful when creating GNU-compatible import libs for third
4775 party DLLs that were built with MS-Windows tools.
4776
4777 @item -k
4778 @itemx --kill-at
4779 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4780 of stdcall functions that will be imported from the DLL. This is
4781 useful when creating an import library for a DLL which exports stdcall
4782 functions but without the usual @samp{@@<number>} symbol name suffix.
4783
4784 This does not change the naming of symbols provided by the import library
4785 to programs linked against it, but only the entries in the import table
4786 (ie the .idata section).
4787
4788 @item -A
4789 @itemx --add-stdcall-alias
4790 Specifies that when @command{dlltool} is creating the exports file it
4791 should add aliases for stdcall symbols without @samp{@@ <number>}
4792 in addition to the symbols with @samp{@@ <number>}.
4793
4794 @item -p
4795 @itemx --ext-prefix-alias @var{prefix}
4796 Causes @command{dlltool} to create external aliases for all DLL
4797 imports with the specified prefix. The aliases are created for both
4798 external and import symbols with no leading underscore.
4799
4800 @item -x
4801 @itemx --no-idata4
4802 Specifies that when @command{dlltool} is creating the exports and library
4803 files it should omit the @code{.idata4} section. This is for compatibility
4804 with certain operating systems.
4805
4806 @item --use-nul-prefixed-import-tables
4807 Specifies that when @command{dlltool} is creating the exports and library
4808 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4809 element. This emulates old gnu import library generation of
4810 @code{dlltool}. By default this option is turned off.
4811
4812 @item -c
4813 @itemx --no-idata5
4814 Specifies that when @command{dlltool} is creating the exports and library
4815 files it should omit the @code{.idata5} section. This is for compatibility
4816 with certain operating systems.
4817
4818 @item -I @var{filename}
4819 @itemx --identify @var{filename}
4820 Specifies that @command{dlltool} should inspect the import library
4821 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4822 of the associated DLL(s). This can be performed in addition to any
4823 other operations indicated by the other options and arguments.
4824 @command{dlltool} fails if the import library does not exist or is not
4825 actually an import library. See also @option{--identify-strict}.
4826
4827 @item --identify-strict
4828 Modifies the behavior of the @option{--identify} option, such
4829 that an error is reported if @var{filename} is associated with
4830 more than one DLL.
4831
4832 @item -i
4833 @itemx --interwork
4834 Specifies that @command{dlltool} should mark the objects in the library
4835 file and exports file that it produces as supporting interworking
4836 between ARM and Thumb code.
4837
4838 @item -n
4839 @itemx --nodelete
4840 Makes @command{dlltool} preserve the temporary assembler files it used to
4841 create the exports file. If this option is repeated then dlltool will
4842 also preserve the temporary object files it uses to create the library
4843 file.
4844
4845 @item -t @var{prefix}
4846 @itemx --temp-prefix @var{prefix}
4847 Makes @command{dlltool} use @var{prefix} when constructing the names of
4848 temporary assembler and object files. By default, the temp file prefix
4849 is generated from the pid.
4850
4851 @item -v
4852 @itemx --verbose
4853 Make dlltool describe what it is doing.
4854
4855 @item -h
4856 @itemx --help
4857 Displays a list of command-line options and then exits.
4858
4859 @item -V
4860 @itemx --version
4861 Displays dlltool's version number and then exits.
4862
4863 @end table
4864
4865 @c man end
4866
4867 @menu
4868 * def file format:: The format of the dlltool @file{.def} file
4869 @end menu
4870
4871 @node def file format
4872 @section The format of the @command{dlltool} @file{.def} file
4873
4874 A @file{.def} file contains any number of the following commands:
4875
4876 @table @asis
4877
4878 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4879 The result is going to be named @var{name}@code{.exe}.
4880
4881 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4882 The result is going to be named @var{name}@code{.dll}.
4883 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4884 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4885 details).
4886
4887 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4888 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4889 Declares @var{name1} as an exported symbol from the DLL, with optional
4890 ordinal number @var{integer}, or declares @var{name1} as an alias
4891 (forward) of the function @var{external-name} in the DLL.
4892 If @var{its_name} is specified, this name is used as string in export table.
4893 @var{module-name}.
4894 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4895 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4896 If you want to use LIBRARY as name then you need to quote it.
4897
4898 @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{]} *}
4899 Declares that @var{external-name} or the exported function whose
4900 ordinal number is @var{integer} is to be imported from the file
4901 @var{module-name}. If @var{internal-name} is specified then this is
4902 the name that the imported function will be referred to in the body of
4903 the DLL.
4904 If @var{its_name} is specified, this name is used as string in import table.
4905 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4906 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4907 If you want to use LIBRARY as name then you need to quote it.
4908
4909 @item @code{DESCRIPTION} @var{string}
4910 Puts @var{string} into the output @file{.exp} file in the
4911 @code{.rdata} section.
4912
4913 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4914 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4915 Generates @code{--stack} or @code{--heap}
4916 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4917 section. The linker will see this and act upon it.
4918
4919 @item @code{CODE} @var{attr} @code{+}
4920 @item @code{DATA} @var{attr} @code{+}
4921 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4922 Generates @code{--attr} @var{section-name} @var{attr} in the output
4923 @code{.drectve} section, where @var{attr} is one of @code{READ},
4924 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4925 this and act upon it.
4926
4927 @end table
4928
4929 @ignore
4930 @c man begin SEEALSO dlltool
4931 The Info pages for @file{binutils}.
4932 @c man end
4933 @end ignore
4934
4935 @node readelf
4936 @chapter readelf
4937
4938 @cindex ELF file information
4939 @kindex readelf
4940
4941 @c man title readelf display information about ELF files
4942
4943 @smallexample
4944 @c man begin SYNOPSIS readelf
4945 readelf [@option{-a}|@option{--all}]
4946 [@option{-h}|@option{--file-header}]
4947 [@option{-l}|@option{--program-headers}|@option{--segments}]
4948 [@option{-S}|@option{--section-headers}|@option{--sections}]
4949 [@option{-g}|@option{--section-groups}]
4950 [@option{-t}|@option{--section-details}]
4951 [@option{-e}|@option{--headers}]
4952 [@option{-s}|@option{--syms}|@option{--symbols}]
4953 [@option{--dyn-syms}|@option{--lto-syms}]
4954 [@option{--sym-base=[0|8|10|16]}]
4955 [@option{--demangle@var{=style}}|@option{--no-demangle}]
4956 [@option{--quiet}]
4957 [@option{--recurse-limit}|@option{--no-recurse-limit}]
4958 [@option{-U} @var{method}|@option{--unicode=}@var{method}]
4959 [@option{-n}|@option{--notes}]
4960 [@option{-r}|@option{--relocs}]
4961 [@option{-u}|@option{--unwind}]
4962 [@option{-d}|@option{--dynamic}]
4963 [@option{-V}|@option{--version-info}]
4964 [@option{-A}|@option{--arch-specific}]
4965 [@option{-D}|@option{--use-dynamic}]
4966 [@option{-L}|@option{--lint}|@option{--enable-checks}]
4967 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4968 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4969 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4970 [@option{-z}|@option{--decompress}]
4971 [@option{-c}|@option{--archive-index}]
4972 [@option{-w[lLiaprmfFsoORtUuTgAck]}|
4973 @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]]
4974 [@option{-wK}|@option{--debug-dump=follow-links}]
4975 [@option{-wN}|@option{--debug-dump=no-follow-links}]
4976 [@option{-wD}|@option{--debug-dump=use-debuginfod}]
4977 [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
4978 [@option{-P}|@option{--process-links}]
4979 [@option{--dwarf-depth=@var{n}}]
4980 [@option{--dwarf-start=@var{n}}]
4981 [@option{--ctf=}@var{section}]
4982 [@option{--ctf-parent=}@var{section}]
4983 [@option{--ctf-symbols=}@var{section}]
4984 [@option{--ctf-strings=}@var{section}]
4985 [@option{--sframe=}@var{section}]
4986 [@option{-I}|@option{--histogram}]
4987 [@option{-v}|@option{--version}]
4988 [@option{-W}|@option{--wide}]
4989 [@option{-T}|@option{--silent-truncation}]
4990 [@option{-H}|@option{--help}]
4991 @var{elffile}@dots{}
4992 @c man end
4993 @end smallexample
4994
4995 @c man begin DESCRIPTION readelf
4996
4997 @command{readelf} displays information about one or more ELF format object
4998 files. The options control what particular information to display.
4999
5000 @var{elffile}@dots{} are the object files to be examined. 32-bit and
5001 64-bit ELF files are supported, as are archives containing ELF files.
5002
5003 This program performs a similar function to @command{objdump} but it
5004 goes into more detail and it exists independently of the @sc{bfd}
5005 library, so if there is a bug in @sc{bfd} then readelf will not be
5006 affected.
5007
5008 @c man end
5009
5010 @c man begin OPTIONS readelf
5011
5012 The long and short forms of options, shown here as alternatives, are
5013 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
5014 given.
5015
5016 @table @env
5017 @item -a
5018 @itemx --all
5019 Equivalent to specifying @option{--file-header},
5020 @option{--program-headers}, @option{--sections}, @option{--symbols},
5021 @option{--relocs}, @option{--dynamic}, @option{--notes},
5022 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
5023 @option{--section-groups} and @option{--histogram}.
5024
5025 Note - this option does not enable @option{--use-dynamic} itself, so
5026 if that option is not present on the command line then dynamic symbols
5027 and dynamic relocs will not be displayed.
5028
5029 @item -h
5030 @itemx --file-header
5031 @cindex ELF file header information
5032 Displays the information contained in the ELF header at the start of the
5033 file.
5034
5035 @item -l
5036 @itemx --program-headers
5037 @itemx --segments
5038 @cindex ELF program header information
5039 @cindex ELF segment information
5040 Displays the information contained in the file's segment headers, if it
5041 has any.
5042
5043 @item --quiet
5044 @cindex quiet
5045 Suppress "no symbols" diagnostic.
5046
5047 @item -S
5048 @itemx --sections
5049 @itemx --section-headers
5050 @cindex ELF section information
5051 Displays the information contained in the file's section headers, if it
5052 has any.
5053
5054 @item -g
5055 @itemx --section-groups
5056 @cindex ELF section group information
5057 Displays the information contained in the file's section groups, if it
5058 has any.
5059
5060 @item -t
5061 @itemx --section-details
5062 @cindex ELF section information
5063 Displays the detailed section information. Implies @option{-S}.
5064
5065 @item -s
5066 @itemx --symbols
5067 @itemx --syms
5068 @cindex ELF symbol table information
5069 Displays the entries in symbol table section of the file, if it has one.
5070 If a symbol has version information associated with it then this is
5071 displayed as well. The version string is displayed as a suffix to the
5072 symbol name, preceded by an @@ character. For example
5073 @samp{foo@@VER_1}. If the version is the default version to be used
5074 when resolving unversioned references to the symbol then it is
5075 displayed as a suffix preceded by two @@ characters. For example
5076 @samp{foo@@@@VER_2}.
5077
5078 @item --dyn-syms
5079 @cindex ELF dynamic symbol table information
5080 Displays the entries in dynamic symbol table section of the file, if it
5081 has one. The output format is the same as the format used by the
5082 @option{--syms} option.
5083
5084 @item --lto-syms
5085 @cindex LTO symbol table
5086 Displays the contents of any LTO symbol tables in the file.
5087
5088 @item --sym-base=[0|8|10|16]
5089 @cindex symbol table size base
5090 Forces the size field of the symbol table to use the given base. Any
5091 unrecognized options will be treated as @samp{0}. @option{--sym-base=0}
5092 represents the default and legacy behaviour. This will output sizes as decimal
5093 for numbers less than 100000. For sizes 100000 and greater hexadecimal notation
5094 will be used with a 0x prefix.
5095 @option{--sym-base=8} will give the symbol sizes in octal.
5096 @option{--sym-base=10} will always give the symbol sizes in decimal.
5097 @option{--sym-base=16} will always give the symbol sizes in hexadecimal with a
5098 0x prefix.
5099
5100 @item -C
5101 @itemx --demangle[=@var{style}]
5102 @cindex demangling in nm
5103 Decode (@dfn{demangle}) low-level symbol names into user-level names.
5104 This makes C++ function names readable. Different compilers have
5105 different mangling styles. The optional demangling style argument can
5106 be used to choose an appropriate demangling style for your
5107 compiler. @xref{c++filt}, for more information on demangling.
5108
5109 @item --no-demangle
5110 Do not demangle low-level symbol names. This is the default.
5111
5112 @item --recurse-limit
5113 @itemx --no-recurse-limit
5114 @itemx --recursion-limit
5115 @itemx --no-recursion-limit
5116 Enables or disables a limit on the amount of recursion performed
5117 whilst demangling strings. Since the name mangling formats allow for
5118 an infinite level of recursion it is possible to create strings whose
5119 decoding will exhaust the amount of stack space available on the host
5120 machine, triggering a memory fault. The limit tries to prevent this
5121 from happening by restricting recursion to 2048 levels of nesting.
5122
5123 The default is for this limit to be enabled, but disabling it may be
5124 necessary in order to demangle truly complicated names. Note however
5125 that if the recursion limit is disabled then stack exhaustion is
5126 possible and any bug reports about such an event will be rejected.
5127
5128 @item -U @var{[d|i|l|e|x|h]}
5129 @itemx --unicode=[default|invalid|locale|escape|hex|highlight]
5130 Controls the display of non-ASCII characters in identifier names.
5131 The default (@option{--unicode=locale} or @option{--unicode=default}) is
5132 to treat them as multibyte characters and display them in the current
5133 locale. All other versions of this option treat the bytes as UTF-8
5134 encoded values and attempt to interpret them. If they cannot be
5135 interpreted or if the @option{--unicode=invalid} option is used then
5136 they are displayed as a sequence of hex bytes, encloses in curly
5137 parethesis characters.
5138
5139 Using the @option{--unicode=escape} option will display the characters
5140 as as unicode escape sequences (@var{\uxxxx}). Using the
5141 @option{--unicode=hex} will display the characters as hex byte
5142 sequences enclosed between angle brackets.
5143
5144 Using the @option{--unicode=highlight} will display the characters as
5145 unicode escape sequences but it will also highlighted them in red,
5146 assuming that colouring is supported by the output device. The
5147 colouring is intended to draw attention to the presence of unicode
5148 sequences when they might not be expected.
5149
5150 @item -e
5151 @itemx --headers
5152 Display all the headers in the file. Equivalent to @option{-h -l -S}.
5153
5154 @item -n
5155 @itemx --notes
5156 @cindex ELF notes
5157 Displays the contents of the NOTE segments and/or sections, if any.
5158
5159 @item -r
5160 @itemx --relocs
5161 @cindex ELF reloc information
5162 Displays the contents of the file's relocation section, if it has one.
5163
5164 @item -u
5165 @itemx --unwind
5166 @cindex unwind information
5167 Displays the contents of the file's unwind section, if it has one. Only
5168 the unwind sections for IA64 ELF files, as well as ARM unwind tables
5169 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
5170 support is not yet implemented for your architecture you could try
5171 dumping the contents of the @var{.eh_frames} section using the
5172 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
5173 options.
5174
5175 @item -d
5176 @itemx --dynamic
5177 @cindex ELF dynamic section information
5178 Displays the contents of the file's dynamic section, if it has one.
5179
5180 @item -V
5181 @itemx --version-info
5182 @cindex ELF version sections information
5183 Displays the contents of the version sections in the file, it they
5184 exist.
5185
5186 @item -A
5187 @itemx --arch-specific
5188 Displays architecture-specific information in the file, if there
5189 is any.
5190
5191 @item -D
5192 @itemx --use-dynamic
5193 When displaying symbols, this option makes @command{readelf} use the
5194 symbol hash tables in the file's dynamic section, rather than the
5195 symbol table sections.
5196
5197 When displaying relocations, this option makes @command{readelf}
5198 display the dynamic relocations rather than the static relocations.
5199
5200 @item -L
5201 @itemx --lint
5202 @itemx --enable-checks
5203 Displays warning messages about possible problems with the file(s)
5204 being examined. If used on its own then all of the contents of the
5205 file(s) will be examined. If used with one of the dumping options
5206 then the warning messages will only be produced for the things being
5207 displayed.
5208
5209 @item -x <number or name>
5210 @itemx --hex-dump=<number or name>
5211 Displays the contents of the indicated section as a hexadecimal bytes.
5212 A number identifies a particular section by index in the section table;
5213 any other string identifies all sections with that name in the object file.
5214
5215 @item -R <number or name>
5216 @itemx --relocated-dump=<number or name>
5217 Displays the contents of the indicated section as a hexadecimal
5218 bytes. A number identifies a particular section by index in the
5219 section table; any other string identifies all sections with that name
5220 in the object file. The contents of the section will be relocated
5221 before they are displayed.
5222
5223 @item -p <number or name>
5224 @itemx --string-dump=<number or name>
5225 Displays the contents of the indicated section as printable strings.
5226 A number identifies a particular section by index in the section table;
5227 any other string identifies all sections with that name in the object file.
5228
5229 @item -z
5230 @itemx --decompress
5231 Requests that the section(s) being dumped by @option{x}, @option{R} or
5232 @option{p} options are decompressed before being displayed. If the
5233 section(s) are not compressed then they are displayed as is.
5234
5235 @item -c
5236 @itemx --archive-index
5237 @cindex Archive file symbol index information
5238 Displays the file symbol index information contained in the header part
5239 of binary archives. Performs the same function as the @option{t}
5240 command to @command{ar}, but without using the BFD library. @xref{ar}.
5241
5242 @item -w[lLiaprmfFsOoRtUuTgAckK]
5243 @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]
5244 @include debug.options.texi
5245
5246 @item -P
5247 @itemx --process-links
5248 Display the contents of non-debug sections found in separate debuginfo
5249 files that are linked to the main file. This option automatically
5250 implies the @option{-wK} option, and only sections requested by other
5251 command line options will be displayed.
5252
5253 @include ctf.options.texi
5254 @item --ctf-symbols=@var{section}
5255 @item --ctf-strings=@var{section}
5256 Specify the name of another section from which the CTF file can inherit
5257 strings and symbols. By default, the @code{.symtab} and its linked
5258 string table are used.
5259
5260 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
5261 other must be specified as well.
5262
5263 @item -I
5264 @itemx --histogram
5265 Display a histogram of bucket list lengths when displaying the contents
5266 of the symbol tables.
5267
5268 @item -v
5269 @itemx --version
5270 Display the version number of readelf.
5271
5272 @item -W
5273 @itemx --wide
5274 Don't break output lines to fit into 80 columns. By default
5275 @command{readelf} breaks section header and segment listing lines for
5276 64-bit ELF files, so that they fit into 80 columns. This option causes
5277 @command{readelf} to print each section header resp. each segment one a
5278 single line, which is far more readable on terminals wider than 80 columns.
5279
5280 @item -T
5281 @itemx --silent-truncation
5282 Normally when readelf is displaying a symbol name, and it has to
5283 truncate the name to fit into an 80 column display, it will add a
5284 suffix of @code{[...]} to the name. This command line option
5285 disables this behaviour, allowing 5 more characters of the name to be
5286 displayed and restoring the old behaviour of readelf (prior to release
5287 2.35).
5288
5289 @item -H
5290 @itemx --help
5291 Display the command-line options understood by @command{readelf}.
5292
5293 @end table
5294
5295 @c man end
5296
5297 @ignore
5298 @c man begin SEEALSO readelf
5299 objdump(1), and the Info entries for @file{binutils}.
5300 @c man end
5301 @end ignore
5302
5303 @node elfedit
5304 @chapter elfedit
5305
5306 @cindex Update ELF header
5307 @kindex elfedit
5308
5309 @c man title elfedit update ELF header and program property of ELF files
5310
5311 @smallexample
5312 @c man begin SYNOPSIS elfedit
5313 elfedit [@option{--input-mach=}@var{machine}]
5314 [@option{--input-type=}@var{type}]
5315 [@option{--input-osabi=}@var{osabi}]
5316 [@option{--input-abiversion=}@var{version}]
5317 @option{--output-mach=}@var{machine}
5318 @option{--output-type=}@var{type}
5319 @option{--output-osabi=}@var{osabi}
5320 @option{--output-abiversion=}@var{version}
5321 @option{--enable-x86-feature=}@var{feature}
5322 @option{--disable-x86-feature=}@var{feature}
5323 [@option{-v}|@option{--version}]
5324 [@option{-h}|@option{--help}]
5325 @var{elffile}@dots{}
5326 @c man end
5327 @end smallexample
5328
5329 @c man begin DESCRIPTION elfedit
5330
5331 @command{elfedit} updates the ELF header and program property of ELF
5332 files which have the matching ELF machine and file types. The options
5333 control how and which fields in the ELF header and program property
5334 should be updated.
5335
5336 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
5337 64-bit ELF files are supported, as are archives containing ELF files.
5338 @c man end
5339
5340 @c man begin OPTIONS elfedit
5341
5342 The long and short forms of options, shown here as alternatives, are
5343 equivalent. At least one of the @option{--output-mach},
5344 @option{--output-type}, @option{--output-osabi},
5345 @option{--output-abiversion},
5346 @option{--enable-x86-feature} and @option{--disable-x86-feature}
5347 options must be given.
5348
5349 @table @env
5350
5351 @item --input-mach=@var{machine}
5352 Set the matching input ELF machine type to @var{machine}. If
5353 @option{--input-mach} isn't specified, it will match any ELF
5354 machine types.
5355
5356 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5357 @var{K1OM} and @var{x86-64}.
5358
5359 @item --output-mach=@var{machine}
5360 Change the ELF machine type in the ELF header to @var{machine}. The
5361 supported ELF machine types are the same as @option{--input-mach}.
5362
5363 @item --input-type=@var{type}
5364 Set the matching input ELF file type to @var{type}. If
5365 @option{--input-type} isn't specified, it will match any ELF file types.
5366
5367 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5368
5369 @item --output-type=@var{type}
5370 Change the ELF file type in the ELF header to @var{type}. The
5371 supported ELF types are the same as @option{--input-type}.
5372
5373 @item --input-osabi=@var{osabi}
5374 Set the matching input ELF file OSABI to @var{osabi}. If
5375 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5376
5377 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5378 @var{GNU}, @var{Linux} (alias for @var{GNU}),
5379 @var{Solaris}, @var{AIX}, @var{Irix},
5380 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5381 @var{NSK}, @var{AROS} and @var{FenixOS}.
5382
5383 @item --output-osabi=@var{osabi}
5384 Change the ELF OSABI in the ELF header to @var{osabi}. The
5385 supported ELF OSABI are the same as @option{--input-osabi}.
5386
5387 @item --input-abiversion=@var{version}
5388 Set the matching input ELF file ABIVERSION to @var{version}.
5389 @var{version} must be between 0 and 255. If @option{--input-abiversion}
5390 isn't specified, it will match any ELF ABIVERSIONs.
5391
5392 @item --output-abiversion=@var{version}
5393 Change the ELF ABIVERSION in the ELF header to @var{version}.
5394 @var{version} must be between 0 and 255.
5395
5396 @item --enable-x86-feature=@var{feature}
5397 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5398 ELF files with machine types of @var{i386} or @var{x86-64}. The
5399 supported features are, @var{ibt}, @var{shstk}, @var{lam_u48} and
5400 @var{lam_u57}.
5401
5402 @item --disable-x86-feature=@var{feature}
5403 Clear the @var{feature} bit in program property in @var{exec} or
5404 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5405 The supported features are the same as @option{--enable-x86-feature}.
5406
5407 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5408 are available only on hosts with @samp{mmap} support.
5409
5410 @item -v
5411 @itemx --version
5412 Display the version number of @command{elfedit}.
5413
5414 @item -h
5415 @itemx --help
5416 Display the command-line options understood by @command{elfedit}.
5417
5418 @end table
5419
5420 @c man end
5421
5422 @ignore
5423 @c man begin SEEALSO elfedit
5424 readelf(1), and the Info entries for @file{binutils}.
5425 @c man end
5426 @end ignore
5427
5428 @node Common Options
5429 @chapter Common Options
5430
5431 The following command-line options are supported by all of the
5432 programs described in this manual.
5433
5434 @c man begin OPTIONS
5435 @table @env
5436 @include at-file.texi
5437 @c man end
5438
5439 @item --help
5440 Display the command-line options supported by the program.
5441
5442 @item --version
5443 Display the version number of the program.
5444
5445 @c man begin OPTIONS
5446 @end table
5447 @c man end
5448
5449 @node Selecting the Target System
5450 @chapter Selecting the Target System
5451
5452 You can specify two aspects of the target system to the @sc{gnu}
5453 binary file utilities, each in several ways:
5454
5455 @itemize @bullet
5456 @item
5457 the target
5458
5459 @item
5460 the architecture
5461 @end itemize
5462
5463 In the following summaries, the lists of ways to specify values are in
5464 order of decreasing precedence. The ways listed first override those
5465 listed later.
5466
5467 The commands to list valid values only list the values for which the
5468 programs you are running were configured. If they were configured with
5469 @option{--enable-targets=all}, the commands list most of the available
5470 values, but a few are left out; not all targets can be configured in at
5471 once because some of them can only be configured @dfn{native} (on hosts
5472 with the same type as the target system).
5473
5474 @menu
5475 * Target Selection::
5476 * Architecture Selection::
5477 @end menu
5478
5479 @node Target Selection
5480 @section Target Selection
5481
5482 A @dfn{target} is an object file format. A given target may be
5483 supported for multiple architectures (@pxref{Architecture Selection}).
5484 A target selection may also have variations for different operating
5485 systems or architectures.
5486
5487 The command to list valid target values is @samp{objdump -i}
5488 (the first column of output contains the relevant information).
5489
5490 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5491 @samp{a.out-sunos-big}.
5492
5493 You can also specify a target using a configuration triplet. This is
5494 the same sort of name that is passed to @file{configure} to specify a
5495 target. When you use a configuration triplet as an argument, it must be
5496 fully canonicalized. You can see the canonical version of a triplet by
5497 running the shell script @file{config.sub} which is included with the
5498 sources.
5499
5500 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5501 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5502
5503 @subheading @command{objdump} Target
5504
5505 Ways to specify:
5506
5507 @enumerate
5508 @item
5509 command-line option: @option{-b} or @option{--target}
5510
5511 @item
5512 environment variable @code{GNUTARGET}
5513
5514 @item
5515 deduced from the input file
5516 @end enumerate
5517
5518 @subheading @command{objcopy} and @command{strip} Input Target
5519
5520 Ways to specify:
5521
5522 @enumerate
5523 @item
5524 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5525
5526 @item
5527 environment variable @code{GNUTARGET}
5528
5529 @item
5530 deduced from the input file
5531 @end enumerate
5532
5533 @subheading @command{objcopy} and @command{strip} Output Target
5534
5535 Ways to specify:
5536
5537 @enumerate
5538 @item
5539 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5540
5541 @item
5542 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5543
5544 @item
5545 environment variable @code{GNUTARGET}
5546
5547 @item
5548 deduced from the input file
5549 @end enumerate
5550
5551 @subheading @command{nm}, @command{size}, and @command{strings} Target
5552
5553 Ways to specify:
5554
5555 @enumerate
5556 @item
5557 command-line option: @option{--target}
5558
5559 @item
5560 environment variable @code{GNUTARGET}
5561
5562 @item
5563 deduced from the input file
5564 @end enumerate
5565
5566 @node Architecture Selection
5567 @section Architecture Selection
5568
5569 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5570 to run. Its name may contain a colon, separating the name of the
5571 processor family from the name of the particular @sc{cpu}.
5572
5573 The command to list valid architecture values is @samp{objdump -i} (the
5574 second column contains the relevant information).
5575
5576 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5577
5578 @subheading @command{objdump} Architecture
5579
5580 Ways to specify:
5581
5582 @enumerate
5583 @item
5584 command-line option: @option{-m} or @option{--architecture}
5585
5586 @item
5587 deduced from the input file
5588 @end enumerate
5589
5590 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5591
5592 Ways to specify:
5593
5594 @enumerate
5595 @item
5596 deduced from the input file
5597 @end enumerate
5598
5599 @node debuginfod
5600 @chapter debuginfod
5601 @cindex separate debug files
5602
5603 debuginfod is a web service that indexes ELF/DWARF debugging resources
5604 by build-id and serves them over HTTP. For more information see:
5605 @emph{https://sourceware.org/elfutils/Debuginfod.html}
5606
5607 Binutils can be built with the debuginfod client library
5608 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5609 This option is enabled by default if @code{libdebuginfod} is installed
5610 and found at configure time. This allows @command{objdump} and
5611 @command{readelf} to automatically query debuginfod servers for
5612 separate debug files when the files are otherwise not found.
5613
5614 debuginfod is packaged with elfutils, starting with version 0.178.
5615 You can get the latest version from `https://sourceware.org/elfutils/'.
5616
5617 The DWARF info dumping tools (@command{readelf} and @command{objdump})
5618 have options to control when they should access the debuginfod
5619 servers. By default this access is enabled.
5620
5621 @node Reporting Bugs
5622 @chapter Reporting Bugs
5623 @cindex bugs
5624 @cindex reporting bugs
5625
5626 Your bug reports play an essential role in making the binary utilities
5627 reliable.
5628
5629 Reporting a bug may help you by bringing a solution to your problem, or
5630 it may not. But in any case the principal function of a bug report is
5631 to help the entire community by making the next version of the binary
5632 utilities work better. Bug reports are your contribution to their
5633 maintenance.
5634
5635 In order for a bug report to serve its purpose, you must include the
5636 information that enables us to fix the bug.
5637
5638 @menu
5639 * Bug Criteria:: Have you found a bug?
5640 * Bug Reporting:: How to report bugs
5641 @end menu
5642
5643 @node Bug Criteria
5644 @section Have You Found a Bug?
5645 @cindex bug criteria
5646
5647 If you are not sure whether you have found a bug, here are some guidelines:
5648
5649 @itemize @bullet
5650 @cindex fatal signal
5651 @cindex crash
5652 @item
5653 If a binary utility gets a fatal signal, for any input whatever, that is
5654 a bug. Reliable utilities never crash.
5655
5656 @cindex error on valid input
5657 @item
5658 If a binary utility produces an error message for valid input, that is a
5659 bug.
5660
5661 @item
5662 If you are an experienced user of binary utilities, your suggestions for
5663 improvement are welcome in any case.
5664 @end itemize
5665
5666 @node Bug Reporting
5667 @section How to Report Bugs
5668 @cindex bug reports
5669 @cindex bugs, reporting
5670
5671 A number of companies and individuals offer support for @sc{gnu}
5672 products. If you obtained the binary utilities from a support
5673 organization, we recommend you contact that organization first.
5674
5675 You can find contact information for many support companies and
5676 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5677 distribution.
5678
5679 @ifset BUGURL
5680 In any event, we also recommend that you send bug reports for the binary
5681 utilities to @value{BUGURL}.
5682 @end ifset
5683
5684 The fundamental principle of reporting bugs usefully is this:
5685 @strong{report all the facts}. If you are not sure whether to state a
5686 fact or leave it out, state it!
5687
5688 Often people omit facts because they think they know what causes the
5689 problem and assume that some details do not matter. Thus, you might
5690 assume that the name of a file you use in an example does not matter.
5691 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5692 a stray memory reference which happens to fetch from the location where
5693 that pathname is stored in memory; perhaps, if the pathname were
5694 different, the contents of that location would fool the utility into
5695 doing the right thing despite the bug. Play it safe and give a
5696 specific, complete example. That is the easiest thing for you to do,
5697 and the most helpful.
5698
5699 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5700 it is new to us. Therefore, always write your bug reports on the assumption
5701 that the bug has not been reported previously.
5702
5703 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5704 bell?'' This cannot help us fix a bug, so it is basically useless. We
5705 respond by asking for enough details to enable us to investigate.
5706 You might as well expedite matters by sending them to begin with.
5707
5708 To enable us to fix the bug, you should include all these things:
5709
5710 @itemize @bullet
5711 @item
5712 The version of the utility. Each utility announces it if you start it
5713 with the @option{--version} argument.
5714
5715 Without this, we will not know whether there is any point in looking for
5716 the bug in the current version of the binary utilities.
5717
5718 @item
5719 Any patches you may have applied to the source, including any patches
5720 made to the @code{BFD} library.
5721
5722 @item
5723 The type of machine you are using, and the operating system name and
5724 version number.
5725
5726 @item
5727 What compiler (and its version) was used to compile the utilities---e.g.
5728 ``@code{gcc-2.7}''.
5729
5730 @item
5731 The command arguments you gave the utility to observe the bug. To
5732 guarantee you will not omit something important, list them all. A copy
5733 of the Makefile (or the output from make) is sufficient.
5734
5735 If we were to try to guess the arguments, we would probably guess wrong
5736 and then we might not encounter the bug.
5737
5738 @item
5739 A complete input file, or set of input files, that will reproduce the
5740 bug. If the utility is reading an object file or files, then it is
5741 generally most helpful to send the actual object files.
5742
5743 If the source files were produced exclusively using @sc{gnu} programs
5744 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5745 may be OK to send the source files rather than the object files. In
5746 this case, be sure to say exactly what version of @command{gcc}, or
5747 whatever, was used to produce the object files. Also say how
5748 @command{gcc}, or whatever, was configured.
5749
5750 @item
5751 A description of what behavior you observe that you believe is
5752 incorrect. For example, ``It gets a fatal signal.''
5753
5754 Of course, if the bug is that the utility gets a fatal signal, then we
5755 will certainly notice it. But if the bug is incorrect output, we might
5756 not notice unless it is glaringly wrong. You might as well not give us
5757 a chance to make a mistake.
5758
5759 Even if the problem you experience is a fatal signal, you should still
5760 say so explicitly. Suppose something strange is going on, such as your
5761 copy of the utility is out of sync, or you have encountered a bug in
5762 the C library on your system. (This has happened!) Your copy might
5763 crash and ours would not. If you told us to expect a crash, then when
5764 ours fails to crash, we would know that the bug was not happening for
5765 us. If you had not told us to expect a crash, then we would not be able
5766 to draw any conclusion from our observations.
5767
5768 @item
5769 If you wish to suggest changes to the source, send us context diffs, as
5770 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5771 option. Always send diffs from the old file to the new file. If you
5772 wish to discuss something in the @command{ld} source, refer to it by
5773 context, not by line number.
5774
5775 The line numbers in our development sources will not match those in your
5776 sources. Your line numbers would convey no useful information to us.
5777 @end itemize
5778
5779 Here are some things that are not necessary:
5780
5781 @itemize @bullet
5782 @item
5783 A description of the envelope of the bug.
5784
5785 Often people who encounter a bug spend a lot of time investigating
5786 which changes to the input file will make the bug go away and which
5787 changes will not affect it.
5788
5789 This is often time consuming and not very useful, because the way we
5790 will find the bug is by running a single example under the debugger
5791 with breakpoints, not by pure deduction from a series of examples.
5792 We recommend that you save your time for something else.
5793
5794 Of course, if you can find a simpler example to report @emph{instead}
5795 of the original one, that is a convenience for us. Errors in the
5796 output will be easier to spot, running under the debugger will take
5797 less time, and so on.
5798
5799 However, simplification is not vital; if you do not want to do this,
5800 report the bug anyway and send us the entire test case you used.
5801
5802 @item
5803 A patch for the bug.
5804
5805 A patch for the bug does help us if it is a good one. But do not omit
5806 the necessary information, such as the test case, on the assumption that
5807 a patch is all we need. We might see problems with your patch and decide
5808 to fix the problem another way, or we might not understand it at all.
5809
5810 Sometimes with programs as complicated as the binary utilities it is
5811 very hard to construct an example that will make the program follow a
5812 certain path through the code. If you do not send us the example, we
5813 will not be able to construct one, so we will not be able to verify that
5814 the bug is fixed.
5815
5816 And if we cannot understand what bug you are trying to fix, or why your
5817 patch should be an improvement, we will not install it. A test case will
5818 help us to understand.
5819
5820 @item
5821 A guess about what the bug is or what it depends on.
5822
5823 Such guesses are usually wrong. Even we cannot guess right about such
5824 things without first using the debugger to find the facts.
5825 @end itemize
5826
5827 @node GNU Free Documentation License
5828 @appendix GNU Free Documentation License
5829
5830 @include fdl.texi
5831
5832 @node Binutils Index
5833 @unnumbered Binutils Index
5834
5835 @printindex cp
5836
5837 @bye