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