35a5a67041e387254a2ceee5812bacee7a7769fd
[binutils-gdb.git] / binutils / doc / binutils.texi
1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
4 @finalout
5 @synindex ky cp
6
7 @c man begin INCLUDE
8 @include bfdver.texi
9 @c man end
10
11 @copying
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2020 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{--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. If a symbol has version information associated with it,
928 then the version information is displayed as well. If the versioned
929 symbol is undefined or hidden from linker, the version string is displayed
930 as a suffix to the symbol name, preceded by an @@ character. For example
931 @samp{foo@@VER_1}. If the version is the default version to be used when
932 resolving unversioned references to the symbol, then it is displayed as a
933 suffix preceded by two @@ characters. For example @samp{foo@@@@VER_2}.
934 @end itemize
935
936 @c man end
937
938 @c man begin OPTIONS nm
939 The long and short forms of options, shown here as alternatives, are
940 equivalent.
941
942 @table @env
943 @item -A
944 @itemx -o
945 @itemx --print-file-name
946 @cindex input file name
947 @cindex file name
948 @cindex source file name
949 Precede each symbol by the name of the input file (or archive member)
950 in which it was found, rather than identifying the input file once only,
951 before all of its symbols.
952
953 @item -a
954 @itemx --debug-syms
955 @cindex debugging symbols
956 Display all symbols, even debugger-only symbols; normally these are not
957 listed.
958
959 @item -B
960 @cindex @command{nm} format
961 @cindex @command{nm} compatibility
962 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
963
964 @item -C
965 @itemx --demangle[=@var{style}]
966 @cindex demangling in nm
967 Decode (@dfn{demangle}) low-level symbol names into user-level names.
968 Besides removing any initial underscore prepended by the system, this
969 makes C++ function names readable. Different compilers have different
970 mangling styles. The optional demangling style argument can be used to
971 choose an appropriate demangling style for your compiler. @xref{c++filt},
972 for more information on demangling.
973
974 @item --no-demangle
975 Do not demangle low-level symbol names. This is the default.
976
977 @item --recurse-limit
978 @itemx --no-recurse-limit
979 @itemx --recursion-limit
980 @itemx --no-recursion-limit
981 Enables or disables a limit on the amount of recursion performed
982 whilst demangling strings. Since the name mangling formats allow for
983 an inifinite level of recursion it is possible to create strings whose
984 decoding will exhaust the amount of stack space available on the host
985 machine, triggering a memory fault. The limit tries to prevent this
986 from happening by restricting recursion to 2048 levels of nesting.
987
988 The default is for this limit to be enabled, but disabling it may be
989 necessary in order to demangle truly complicated names. Note however
990 that if the recursion limit is disabled then stack exhaustion is
991 possible and any bug reports about such an event will be rejected.
992
993 @item -D
994 @itemx --dynamic
995 @cindex dynamic symbols
996 Display the dynamic symbols rather than the normal symbols. This is
997 only meaningful for dynamic objects, such as certain types of shared
998 libraries.
999
1000 @item -f @var{format}
1001 @itemx --format=@var{format}
1002 @cindex @command{nm} format
1003 @cindex @command{nm} compatibility
1004 Use the output format @var{format}, which can be @code{bsd},
1005 @code{sysv}, or @code{posix}. The default is @code{bsd}.
1006 Only the first character of @var{format} is significant; it can be
1007 either upper or lower case.
1008
1009 @item -g
1010 @itemx --extern-only
1011 @cindex external symbols
1012 Display only external symbols.
1013
1014 @item -h
1015 @itemx --help
1016 Show a summary of the options to @command{nm} and exit.
1017
1018 @item -l
1019 @itemx --line-numbers
1020 @cindex symbol line numbers
1021 For each symbol, use debugging information to try to find a filename and
1022 line number. For a defined symbol, look for the line number of the
1023 address of the symbol. For an undefined symbol, look for the line
1024 number of a relocation entry which refers to the symbol. If line number
1025 information can be found, print it after the other symbol information.
1026
1027 @item --inlines
1028 @cindex objdump inlines
1029 When option @option{-l} is active, if the address belongs to a
1030 function that was inlined, then this option causes the source
1031 information for all enclosing scopes back to the first non-inlined
1032 function to be printed as well. For example, if @code{main} inlines
1033 @code{callee1} which inlines @code{callee2}, and address is from
1034 @code{callee2}, the source information for @code{callee1} and @code{main}
1035 will also be printed.
1036
1037 @item -n
1038 @itemx -v
1039 @itemx --numeric-sort
1040 Sort symbols numerically by their addresses, rather than alphabetically
1041 by their names.
1042
1043 @item -p
1044 @itemx --no-sort
1045 @cindex sorting symbols
1046 Do not bother to sort the symbols in any order; print them in the order
1047 encountered.
1048
1049 @item -P
1050 @itemx --portability
1051 Use the POSIX.2 standard output format instead of the default format.
1052 Equivalent to @samp{-f posix}.
1053
1054 @item -r
1055 @itemx --reverse-sort
1056 Reverse the order of the sort (whether numeric or alphabetic); let the
1057 last come first.
1058
1059 @item -S
1060 @itemx --print-size
1061 Print both value and size of defined symbols for the @code{bsd} output style.
1062 This option has no effect for object formats that do not record symbol
1063 sizes, unless @samp{--size-sort} is also used in which case a
1064 calculated size is displayed.
1065
1066 @item -s
1067 @itemx --print-armap
1068 @cindex symbol index, listing
1069 When listing symbols from archive members, include the index: a mapping
1070 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1071 contain definitions for which names.
1072
1073 @item -t @var{radix}
1074 @itemx --radix=@var{radix}
1075 Use @var{radix} as the radix for printing the symbol values. It must be
1076 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1077
1078 @item -u
1079 @itemx --undefined-only
1080 @cindex external symbols
1081 @cindex undefined symbols
1082 Display only undefined symbols (those external to each object file).
1083
1084 @item -V
1085 @itemx --version
1086 Show the version number of @command{nm} and exit.
1087
1088 @item -X
1089 This option is ignored for compatibility with the AIX version of
1090 @command{nm}. It takes one parameter which must be the string
1091 @option{32_64}. The default mode of AIX @command{nm} corresponds
1092 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1093
1094 @item --defined-only
1095 @cindex external symbols
1096 @cindex undefined symbols
1097 Display only defined symbols for each object file.
1098
1099 @item --plugin @var{name}
1100 @cindex plugins
1101 Load the plugin called @var{name} to add support for extra target
1102 types. This option is only available if the toolchain has been built
1103 with plugin support enabled.
1104
1105 If @option{--plugin} is not provided, but plugin support has been
1106 enabled then @command{nm} iterates over the files in
1107 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1108 plugin that claims the object in question is used.
1109
1110 Please note that this plugin search directory is @emph{not} the one
1111 used by @command{ld}'s @option{-plugin} option. In order to make
1112 @command{nm} use the linker plugin it must be copied into the
1113 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1114 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1115 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1116 is always backwards compatible with earlier versions, so it is
1117 sufficient to just copy the newest one.
1118
1119 @item --size-sort
1120 Sort symbols by size. For ELF objects symbol sizes are read from the
1121 ELF, for other object types the symbol sizes are computed as the
1122 difference between the value of the symbol and the value of the symbol
1123 with the next higher value. If the @code{bsd} output format is used
1124 the size of the symbol is printed, rather than the value, and
1125 @samp{-S} must be used in order both size and value to be printed.
1126
1127 @item --special-syms
1128 Display symbols which have a target-specific special meaning. These
1129 symbols are usually used by the target for some special processing and
1130 are not normally helpful when included in the normal symbol lists.
1131 For example for ARM targets this option would skip the mapping symbols
1132 used to mark transitions between ARM code, THUMB code and data.
1133
1134 @item --synthetic
1135 Include synthetic symbols in the output. These are special symbols
1136 created by the linker for various purposes. They are not shown by
1137 default since they are not part of the binary's original source code.
1138
1139 @item --target=@var{bfdname}
1140 @cindex object code format
1141 Specify an object code format other than your system's default format.
1142 @xref{Target Selection}, for more information.
1143
1144 @end table
1145
1146 @c man end
1147
1148 @ignore
1149 @c man begin SEEALSO nm
1150 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1151 @c man end
1152 @end ignore
1153
1154 @node objcopy
1155 @chapter objcopy
1156
1157 @c man title objcopy copy and translate object files
1158
1159 @smallexample
1160 @c man begin SYNOPSIS objcopy
1161 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1162 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1163 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1164 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1165 [@option{-S}|@option{--strip-all}]
1166 [@option{-g}|@option{--strip-debug}]
1167 [@option{--strip-unneeded}]
1168 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1169 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1170 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1171 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1172 [@option{--localize-hidden}]
1173 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1174 [@option{--globalize-symbol=}@var{symbolname}]
1175 [@option{--globalize-symbols=}@var{filename}]
1176 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1177 [@option{-w}|@option{--wildcard}]
1178 [@option{-x}|@option{--discard-all}]
1179 [@option{-X}|@option{--discard-locals}]
1180 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1181 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1182 [@option{--interleave-width=}@var{width}]
1183 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1184 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1185 [@option{--keep-section=}@var{sectionpattern}]
1186 [@option{--remove-relocations=}@var{sectionpattern}]
1187 [@option{-p}|@option{--preserve-dates}]
1188 [@option{-D}|@option{--enable-deterministic-archives}]
1189 [@option{-U}|@option{--disable-deterministic-archives}]
1190 [@option{--debugging}]
1191 [@option{--gap-fill=}@var{val}]
1192 [@option{--pad-to=}@var{address}]
1193 [@option{--set-start=}@var{val}]
1194 [@option{--adjust-start=}@var{incr}]
1195 [@option{--change-addresses=}@var{incr}]
1196 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1197 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1198 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1199 [@option{--change-warnings}] [@option{--no-change-warnings}]
1200 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1201 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1202 [@option{--add-section} @var{sectionname}=@var{filename}]
1203 [@option{--dump-section} @var{sectionname}=@var{filename}]
1204 [@option{--update-section} @var{sectionname}=@var{filename}]
1205 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1206 [@option{--long-section-names} @{enable,disable,keep@}]
1207 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1208 [@option{--reverse-bytes=}@var{num}]
1209 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1210 [@option{--redefine-sym} @var{old}=@var{new}]
1211 [@option{--redefine-syms=}@var{filename}]
1212 [@option{--weaken}]
1213 [@option{--keep-symbols=}@var{filename}]
1214 [@option{--strip-symbols=}@var{filename}]
1215 [@option{--strip-unneeded-symbols=}@var{filename}]
1216 [@option{--keep-global-symbols=}@var{filename}]
1217 [@option{--localize-symbols=}@var{filename}]
1218 [@option{--weaken-symbols=}@var{filename}]
1219 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1220 [@option{--alt-machine-code=}@var{index}]
1221 [@option{--prefix-symbols=}@var{string}]
1222 [@option{--prefix-sections=}@var{string}]
1223 [@option{--prefix-alloc-sections=}@var{string}]
1224 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1225 [@option{--keep-file-symbols}]
1226 [@option{--only-keep-debug}]
1227 [@option{--strip-dwo}]
1228 [@option{--extract-dwo}]
1229 [@option{--extract-symbol}]
1230 [@option{--writable-text}]
1231 [@option{--readonly-text}]
1232 [@option{--pure}]
1233 [@option{--impure}]
1234 [@option{--file-alignment=}@var{num}]
1235 [@option{--heap=}@var{size}]
1236 [@option{--image-base=}@var{address}]
1237 [@option{--section-alignment=}@var{num}]
1238 [@option{--stack=}@var{size}]
1239 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1240 [@option{--compress-debug-sections}]
1241 [@option{--decompress-debug-sections}]
1242 [@option{--elf-stt-common=@var{val}}]
1243 [@option{--merge-notes}]
1244 [@option{--no-merge-notes}]
1245 [@option{--verilog-data-width=@var{val}}]
1246 [@option{-v}|@option{--verbose}]
1247 [@option{-V}|@option{--version}]
1248 [@option{--help}] [@option{--info}]
1249 @var{infile} [@var{outfile}]
1250 @c man end
1251 @end smallexample
1252
1253 @c man begin DESCRIPTION objcopy
1254 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1255 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1256 read and write the object files. It can write the destination object
1257 file in a format different from that of the source object file. The
1258 exact behavior of @command{objcopy} is controlled by command-line options.
1259 Note that @command{objcopy} should be able to copy a fully linked file
1260 between any two formats. However, copying a relocatable object file
1261 between any two formats may not work as expected.
1262
1263 @command{objcopy} creates temporary files to do its translations and
1264 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1265 translation work; it has access to all the formats described in @sc{bfd}
1266 and thus is able to recognize most formats without being told
1267 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1268
1269 @command{objcopy} can be used to generate S-records by using an output
1270 target of @samp{srec} (e.g., use @samp{-O srec}).
1271
1272 @command{objcopy} can be used to generate a raw binary file by using an
1273 output target of @samp{binary} (e.g., use @option{-O binary}). When
1274 @command{objcopy} generates a raw binary file, it will essentially produce
1275 a memory dump of the contents of the input object file. All symbols and
1276 relocation information will be discarded. The memory dump will start at
1277 the load address of the lowest section copied into the output file.
1278
1279 When generating an S-record or a raw binary file, it may be helpful to
1280 use @option{-S} to remove sections containing debugging information. In
1281 some cases @option{-R} will be useful to remove sections which contain
1282 information that is not needed by the binary file.
1283
1284 Note---@command{objcopy} is not able to change the endianness of its input
1285 files. If the input format has an endianness (some formats do not),
1286 @command{objcopy} can only copy the inputs into file formats that have the
1287 same endianness or which have no endianness (e.g., @samp{srec}).
1288 (However, see the @option{--reverse-bytes} option.)
1289
1290 @c man end
1291
1292 @c man begin OPTIONS objcopy
1293
1294 @table @env
1295 @item @var{infile}
1296 @itemx @var{outfile}
1297 The input and output files, respectively.
1298 If you do not specify @var{outfile}, @command{objcopy} creates a
1299 temporary file and destructively renames the result with
1300 the name of @var{infile}.
1301
1302 @item -I @var{bfdname}
1303 @itemx --input-target=@var{bfdname}
1304 Consider the source file's object format to be @var{bfdname}, rather than
1305 attempting to deduce it. @xref{Target Selection}, for more information.
1306
1307 @item -O @var{bfdname}
1308 @itemx --output-target=@var{bfdname}
1309 Write the output file using the object format @var{bfdname}.
1310 @xref{Target Selection}, for more information.
1311
1312 @item -F @var{bfdname}
1313 @itemx --target=@var{bfdname}
1314 Use @var{bfdname} as the object format for both the input and the output
1315 file; i.e., simply transfer data from source to destination with no
1316 translation. @xref{Target Selection}, for more information.
1317
1318 @item -B @var{bfdarch}
1319 @itemx --binary-architecture=@var{bfdarch}
1320 Useful when transforming a architecture-less input file into an object file.
1321 In this case the output architecture can be set to @var{bfdarch}. This
1322 option will be ignored if the input file has a known @var{bfdarch}. You
1323 can access this binary data inside a program by referencing the special
1324 symbols that are created by the conversion process. These symbols are
1325 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1326 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1327 an object file and then access it in your code using these symbols.
1328
1329 @item -j @var{sectionpattern}
1330 @itemx --only-section=@var{sectionpattern}
1331 Copy only the indicated sections from the input file to the output file.
1332 This option may be given more than once. Note that using this option
1333 inappropriately may make the output file unusable. Wildcard
1334 characters are accepted in @var{sectionpattern}.
1335
1336 If the first character of @var{sectionpattern} is the exclamation
1337 point (!) then matching sections will not be copied, even if earlier
1338 use of @option{--only-section} on the same command line would
1339 otherwise copy it. For example:
1340
1341 @smallexample
1342 --only-section=.text.* --only-section=!.text.foo
1343 @end smallexample
1344
1345 will copy all sectinos maching '.text.*' but not the section
1346 '.text.foo'.
1347
1348 @item -R @var{sectionpattern}
1349 @itemx --remove-section=@var{sectionpattern}
1350 Remove any section matching @var{sectionpattern} from the output file.
1351 This option may be given more than once. Note that using this option
1352 inappropriately may make the output file unusable. Wildcard
1353 characters are accepted in @var{sectionpattern}. Using both the
1354 @option{-j} and @option{-R} options together results in undefined
1355 behaviour.
1356
1357 If the first character of @var{sectionpattern} is the exclamation
1358 point (!) then matching sections will not be removed even if an
1359 earlier use of @option{--remove-section} on the same command line
1360 would otherwise remove it. For example:
1361
1362 @smallexample
1363 --remove-section=.text.* --remove-section=!.text.foo
1364 @end smallexample
1365
1366 will remove all sections matching the pattern '.text.*', but will not
1367 remove the section '.text.foo'.
1368
1369 @item --keep-section=@var{sectionpattern}
1370 When removing sections from the output file, keep sections that match
1371 @var{sectionpattern}.
1372
1373 @item --remove-relocations=@var{sectionpattern}
1374 Remove non-dynamic relocations from the output file for any section
1375 matching @var{sectionpattern}. This option may be given more than
1376 once. Note that using this option inappropriately may make the output
1377 file unusable, and attempting to remove a dynamic relocation section
1378 such as @samp{.rela.plt} from an executable or shared library with
1379 @option{--remove-relocations=.plt} will not work. Wildcard characters
1380 are accepted in @var{sectionpattern}.
1381 For example:
1382
1383 @smallexample
1384 --remove-relocations=.text.*
1385 @end smallexample
1386
1387 will remove the relocations for all sections matching the pattern
1388 '.text.*'.
1389
1390 If the first character of @var{sectionpattern} is the exclamation
1391 point (!) then matching sections will not have their relocation
1392 removed even if an earlier use of @option{--remove-relocations} on the
1393 same command line would otherwise cause the relocations to be removed.
1394 For example:
1395
1396 @smallexample
1397 --remove-relocations=.text.* --remove-relocations=!.text.foo
1398 @end smallexample
1399
1400 will remove all relocations for sections matching the pattern
1401 '.text.*', but will not remove relocations for the section
1402 '.text.foo'.
1403
1404 @item -S
1405 @itemx --strip-all
1406 Do not copy relocation and symbol information from the source file.
1407
1408 @item -g
1409 @itemx --strip-debug
1410 Do not copy debugging symbols or sections from the source file.
1411
1412 @item --strip-unneeded
1413 Strip all symbols that are not needed for relocation processing.
1414
1415 @item -K @var{symbolname}
1416 @itemx --keep-symbol=@var{symbolname}
1417 When stripping symbols, keep symbol @var{symbolname} even if it would
1418 normally be stripped. This option may be given more than once.
1419
1420 @item -N @var{symbolname}
1421 @itemx --strip-symbol=@var{symbolname}
1422 Do not copy symbol @var{symbolname} from the source file. This option
1423 may be given more than once.
1424
1425 @item --strip-unneeded-symbol=@var{symbolname}
1426 Do not copy symbol @var{symbolname} from the source file unless it is needed
1427 by a relocation. This option may be given more than once.
1428
1429 @item -G @var{symbolname}
1430 @itemx --keep-global-symbol=@var{symbolname}
1431 Keep only symbol @var{symbolname} global. Make all other symbols local
1432 to the file, so that they are not visible externally. This option may
1433 be given more than once. Note: this option cannot be used in
1434 conjunction with the @option{--globalize-symbol} or
1435 @option{--globalize-symbols} options.
1436
1437 @item --localize-hidden
1438 In an ELF object, mark all symbols that have hidden or internal visibility
1439 as local. This option applies on top of symbol-specific localization options
1440 such as @option{-L}.
1441
1442 @item -L @var{symbolname}
1443 @itemx --localize-symbol=@var{symbolname}
1444 Convert a global or weak symbol called @var{symbolname} into a local
1445 symbol, so that it is not visible externally. This option may be
1446 given more than once. Note - unique symbols are not converted.
1447
1448 @item -W @var{symbolname}
1449 @itemx --weaken-symbol=@var{symbolname}
1450 Make symbol @var{symbolname} weak. This option may be given more than once.
1451
1452 @item --globalize-symbol=@var{symbolname}
1453 Give symbol @var{symbolname} global scoping so that it is visible
1454 outside of the file in which it is defined. This option may be given
1455 more than once. Note: this option cannot be used in conjunction with
1456 the @option{-G} or @option{--keep-global-symbol} options.
1457
1458 @item -w
1459 @itemx --wildcard
1460 Permit regular expressions in @var{symbolname}s used in other command
1461 line options. The question mark (?), asterisk (*), backslash (\) and
1462 square brackets ([]) operators can be used anywhere in the symbol
1463 name. If the first character of the symbol name is the exclamation
1464 point (!) then the sense of the switch is reversed for that symbol.
1465 For example:
1466
1467 @smallexample
1468 -w -W !foo -W fo*
1469 @end smallexample
1470
1471 would cause objcopy to weaken all symbols that start with ``fo''
1472 except for the symbol ``foo''.
1473
1474 @item -x
1475 @itemx --discard-all
1476 Do not copy non-global symbols from the source file.
1477 @c FIXME any reason to prefer "non-global" to "local" here?
1478
1479 @item -X
1480 @itemx --discard-locals
1481 Do not copy compiler-generated local symbols.
1482 (These usually start with @samp{L} or @samp{.}.)
1483
1484 @item -b @var{byte}
1485 @itemx --byte=@var{byte}
1486 If interleaving has been enabled via the @option{--interleave} option
1487 then start the range of bytes to keep at the @var{byte}th byte.
1488 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1489 @var{breadth} is the value given by the @option{--interleave} option.
1490
1491 @item -i [@var{breadth}]
1492 @itemx --interleave[=@var{breadth}]
1493 Only copy a range out of every @var{breadth} bytes. (Header data is
1494 not affected). Select which byte in the range begins the copy with
1495 the @option{--byte} option. Select the width of the range with the
1496 @option{--interleave-width} option.
1497
1498 This option is useful for creating files to program @sc{rom}. It is
1499 typically used with an @code{srec} output target. Note that
1500 @command{objcopy} will complain if you do not specify the
1501 @option{--byte} option as well.
1502
1503 The default interleave breadth is 4, so with @option{--byte} set to 0,
1504 @command{objcopy} would copy the first byte out of every four bytes
1505 from the input to the output.
1506
1507 @item --interleave-width=@var{width}
1508 When used with the @option{--interleave} option, copy @var{width}
1509 bytes at a time. The start of the range of bytes to be copied is set
1510 by the @option{--byte} option, and the extent of the range is set with
1511 the @option{--interleave} option.
1512
1513 The default value for this option is 1. The value of @var{width} plus
1514 the @var{byte} value set by the @option{--byte} option must not exceed
1515 the interleave breadth set by the @option{--interleave} option.
1516
1517 This option can be used to create images for two 16-bit flashes interleaved
1518 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1519 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1520 commands. If the input was '12345678' then the outputs would be
1521 '1256' and '3478' respectively.
1522
1523 @item -p
1524 @itemx --preserve-dates
1525 Set the access and modification dates of the output file to be the same
1526 as those of the input file.
1527
1528 @item -D
1529 @itemx --enable-deterministic-archives
1530 @cindex deterministic archives
1531 @kindex --enable-deterministic-archives
1532 Operate in @emph{deterministic} mode. When copying archive members
1533 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1534 and use consistent file modes for all files.
1535
1536 If @file{binutils} was configured with
1537 @option{--enable-deterministic-archives}, then this mode is on by default.
1538 It can be disabled with the @samp{-U} option, below.
1539
1540 @item -U
1541 @itemx --disable-deterministic-archives
1542 @cindex deterministic archives
1543 @kindex --enable-deterministic-archives
1544 Do @emph{not} operate in @emph{deterministic} mode. This is the
1545 inverse of the @option{-D} option, above: when copying archive members
1546 and writing the archive index, use their actual UID, GID, timestamp,
1547 and file mode values.
1548
1549 This is the default unless @file{binutils} was configured with
1550 @option{--enable-deterministic-archives}.
1551
1552 @item --debugging
1553 Convert debugging information, if possible. This is not the default
1554 because only certain debugging formats are supported, and the
1555 conversion process can be time consuming.
1556
1557 @item --gap-fill @var{val}
1558 Fill gaps between sections with @var{val}. This operation applies to
1559 the @emph{load address} (LMA) of the sections. It is done by increasing
1560 the size of the section with the lower address, and filling in the extra
1561 space created with @var{val}.
1562
1563 @item --pad-to @var{address}
1564 Pad the output file up to the load address @var{address}. This is
1565 done by increasing the size of the last section. The extra space is
1566 filled in with the value specified by @option{--gap-fill} (default zero).
1567
1568 @item --set-start @var{val}
1569 Set the start address (also known as the entry address) of the new
1570 file to @var{val}. Not all object file formats support setting the
1571 start address.
1572
1573 @item --change-start @var{incr}
1574 @itemx --adjust-start @var{incr}
1575 @cindex changing start address
1576 Change the start address (also known as the entry address) by adding
1577 @var{incr}. Not all object file formats support setting the start
1578 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[lLiaprmfFsoORtUuTgAckK]}|
2155 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=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.
2473 @table @code
2474 @item x86-64
2475 @itemx i386
2476 @itemx i8086
2477 Select disassembly for the given architecture.
2478
2479 @item intel
2480 @itemx att
2481 Select between intel syntax mode and AT&T syntax mode.
2482
2483 @item amd64
2484 @itemx intel64
2485 Select between AMD64 ISA and Intel64 ISA.
2486
2487 @item intel-mnemonic
2488 @itemx att-mnemonic
2489 Select between intel mnemonic mode and AT&T mnemonic mode.
2490 Note: @code{intel-mnemonic} implies @code{intel} and
2491 @code{att-mnemonic} implies @code{att}.
2492
2493 @item addr64
2494 @itemx addr32
2495 @itemx addr16
2496 @itemx data32
2497 @itemx data16
2498 Specify the default address size and operand size. These five options
2499 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2500 appear later in the option string.
2501
2502 @item suffix
2503 When in AT&T mode and also for a limited set of instructions when in Intel
2504 mode, instructs the disassembler to print a mnemonic suffix even when the
2505 suffix could be inferred by the operands or, for certain instructions, the
2506 execution mode's defaults.
2507 @end table
2508
2509 For PowerPC, the @option{-M} argument @option{raw} selects
2510 disasssembly of hardware insns rather than aliases. For example, you
2511 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2512 rather than @code{li}. All of the @option{-m} arguments for
2513 @command{gas} that select a CPU are supported. These are:
2514 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2515 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2516 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2517 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2518 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2519 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2520 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2521 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2522 @option{power8}, @option{power9}, @option{power10}, @option{ppc},
2523 @option{ppc32}, @option{ppc64}, @option{ppc64bridge}, @option{ppcps},
2524 @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2525 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9}, @option{pwr10},
2526 @option{pwrx}, @option{titan}, and @option{vle}.
2527 @option{32} and @option{64} modify the default or a prior CPU
2528 selection, disabling and enabling 64-bit insns respectively. In
2529 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2530 and @option{spe} add capabilities to a previous @emph{or later} CPU
2531 selection. @option{any} will disassemble any opcode known to
2532 binutils, but in cases where an opcode has two different meanings or
2533 different arguments, you may not see the disassembly you expect.
2534 If you disassemble without giving a CPU selection, a default will be
2535 chosen from information gleaned by BFD from the object files headers,
2536 but the result again may not be as you expect.
2537
2538 For MIPS, this option controls the printing of instruction mnemonic
2539 names and register names in disassembled instructions. Multiple
2540 selections from the following may be specified as a comma separated
2541 string, and invalid options are ignored:
2542
2543 @table @code
2544 @item no-aliases
2545 Print the 'raw' instruction mnemonic instead of some pseudo
2546 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2547 'sll' instead of 'nop', etc.
2548
2549 @item msa
2550 Disassemble MSA instructions.
2551
2552 @item virt
2553 Disassemble the virtualization ASE instructions.
2554
2555 @item xpa
2556 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2557
2558 @item gpr-names=@var{ABI}
2559 Print GPR (general-purpose register) names as appropriate
2560 for the specified ABI. By default, GPR names are selected according to
2561 the ABI of the binary being disassembled.
2562
2563 @item fpr-names=@var{ABI}
2564 Print FPR (floating-point register) names as
2565 appropriate for the specified ABI. By default, FPR numbers are printed
2566 rather than names.
2567
2568 @item cp0-names=@var{ARCH}
2569 Print CP0 (system control coprocessor; coprocessor 0) register names
2570 as appropriate for the CPU or architecture specified by
2571 @var{ARCH}. By default, CP0 register names are selected according to
2572 the architecture and CPU of the binary being disassembled.
2573
2574 @item hwr-names=@var{ARCH}
2575 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2576 as appropriate for the CPU or architecture specified by
2577 @var{ARCH}. By default, HWR names are selected according to
2578 the architecture and CPU of the binary being disassembled.
2579
2580 @item reg-names=@var{ABI}
2581 Print GPR and FPR names as appropriate for the selected ABI.
2582
2583 @item reg-names=@var{ARCH}
2584 Print CPU-specific register names (CP0 register and HWR names)
2585 as appropriate for the selected CPU or architecture.
2586 @end table
2587
2588 For any of the options listed above, @var{ABI} or
2589 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2590 rather than names, for the selected types of registers.
2591 You can list the available values of @var{ABI} and @var{ARCH} using
2592 the @option{--help} option.
2593
2594 For VAX, you can specify function entry addresses with @option{-M
2595 entry:0xf00ba}. You can use this multiple times to properly
2596 disassemble VAX binary files that don't contain symbol tables (like
2597 ROM dumps). In these cases, the function entry mask would otherwise
2598 be decoded as VAX instructions, which would probably lead the rest
2599 of the function being wrongly disassembled.
2600
2601 @item -p
2602 @itemx --private-headers
2603 Print information that is specific to the object file format. The exact
2604 information printed depends upon the object file format. For some
2605 object file formats, no additional information is printed.
2606
2607 @item -P @var{options}
2608 @itemx --private=@var{options}
2609 Print information that is specific to the object file format. The
2610 argument @var{options} is a comma separated list that depends on the
2611 format (the lists of options is displayed with the help).
2612
2613 For XCOFF, the available options are:
2614 @table @code
2615 @item header
2616 @item aout
2617 @item sections
2618 @item syms
2619 @item relocs
2620 @item lineno,
2621 @item loader
2622 @item except
2623 @item typchk
2624 @item traceback
2625 @item toc
2626 @item ldinfo
2627 @end table
2628
2629 Not all object formats support this option. In particular the ELF
2630 format does not use it.
2631
2632 @item -r
2633 @itemx --reloc
2634 @cindex relocation entries, in object file
2635 Print the relocation entries of the file. If used with @option{-d} or
2636 @option{-D}, the relocations are printed interspersed with the
2637 disassembly.
2638
2639 @item -R
2640 @itemx --dynamic-reloc
2641 @cindex dynamic relocation entries, in object file
2642 Print the dynamic relocation entries of the file. This is only
2643 meaningful for dynamic objects, such as certain types of shared
2644 libraries. As for @option{-r}, if used with @option{-d} or
2645 @option{-D}, the relocations are printed interspersed with the
2646 disassembly.
2647
2648 @item -s
2649 @itemx --full-contents
2650 @cindex sections, full contents
2651 @cindex object file sections
2652 Display the full contents of any sections requested. By default all
2653 non-empty sections are displayed.
2654
2655 @item -S
2656 @itemx --source
2657 @cindex source disassembly
2658 @cindex disassembly, with source
2659 Display source code intermixed with disassembly, if possible. Implies
2660 @option{-d}.
2661
2662 @item --source-comment[=@var{txt}]
2663 @cindex source disassembly
2664 @cindex disassembly, with source
2665 Like the @option{-S} option, but all source code lines are displayed
2666 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2667 string which can be used to distinguish the assembler code from the
2668 source code. If @var{txt} is not provided then a default string of
2669 @var{``# ``} (hash followed by a space), will be used.
2670
2671 @item --prefix=@var{prefix}
2672 @cindex Add prefix to absolute paths
2673 Specify @var{prefix} to add to the absolute paths when used with
2674 @option{-S}.
2675
2676 @item --prefix-strip=@var{level}
2677 @cindex Strip absolute paths
2678 Indicate how many initial directory names to strip off the hardwired
2679 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2680
2681 @item --show-raw-insn
2682 When disassembling instructions, print the instruction in hex as well as
2683 in symbolic form. This is the default except when
2684 @option{--prefix-addresses} is used.
2685
2686 @item --no-show-raw-insn
2687 When disassembling instructions, do not print the instruction bytes.
2688 This is the default when @option{--prefix-addresses} is used.
2689
2690 @item --insn-width=@var{width}
2691 @cindex Instruction width
2692 Display @var{width} bytes on a single line when disassembling
2693 instructions.
2694
2695 @item --visualize-jumps[=color|=extended-color|=off]
2696 Visualize jumps that stay inside a function by drawing ASCII art between
2697 the start and target addresses. The optional @option{=color} argument
2698 adds color to the output using simple terminal colors. Alternatively
2699 the @option{=extended-color} argument will add color using 8bit
2700 colors, but these might not work on all terminals.
2701
2702 If it is necessary to disable the @option{visualize-jumps} option
2703 after it has previously been enabled then use
2704 @option{visualize-jumps=off}.
2705
2706 @item -W[lLiaprmfFsoORtUuTgAckK]
2707 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
2708 @include debug.options.texi
2709
2710 @item --dwarf-check
2711 Enable additional checks for consistency of Dwarf information.
2712
2713 @include ctf.options.texi
2714
2715 @item -G
2716 @itemx --stabs
2717 @cindex stab
2718 @cindex .stab
2719 @cindex debug symbols
2720 @cindex ELF object file format
2721 Display the full contents of any sections requested. Display the
2722 contents of the .stab and .stab.index and .stab.excl sections from an
2723 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2724 @code{.stab} debugging symbol-table entries are carried in an ELF
2725 section. In most other file formats, debugging symbol-table entries are
2726 interleaved with linkage symbols, and are visible in the @option{--syms}
2727 output.
2728
2729 @item --start-address=@var{address}
2730 @cindex start-address
2731 Start displaying data at the specified address. This affects the output
2732 of the @option{-d}, @option{-r} and @option{-s} options.
2733
2734 @item --stop-address=@var{address}
2735 @cindex stop-address
2736 Stop displaying data at the specified address. This affects the output
2737 of the @option{-d}, @option{-r} and @option{-s} options.
2738
2739 @item -t
2740 @itemx --syms
2741 @cindex symbol table entries, printing
2742 Print the symbol table entries of the file.
2743 This is similar to the information provided by the @samp{nm} program,
2744 although the display format is different. The format of the output
2745 depends upon the format of the file being dumped, but there are two main
2746 types. One looks like this:
2747
2748 @smallexample
2749 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2750 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2751 @end smallexample
2752
2753 where the number inside the square brackets is the number of the entry
2754 in the symbol table, the @var{sec} number is the section number, the
2755 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2756 symbol's type, the @var{scl} number is the symbol's storage class and
2757 the @var{nx} value is the number of auxilary entries associated with
2758 the symbol. The last two fields are the symbol's value and its name.
2759
2760 The other common output format, usually seen with ELF based files,
2761 looks like this:
2762
2763 @smallexample
2764 00000000 l d .bss 00000000 .bss
2765 00000000 g .text 00000000 fred
2766 @end smallexample
2767
2768 Here the first number is the symbol's value (sometimes refered to as
2769 its address). The next field is actually a set of characters and
2770 spaces indicating the flag bits that are set on the symbol. These
2771 characters are described below. Next is the section with which the
2772 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2773 not connected with any section), or @emph{*UND*} if the section is
2774 referenced in the file being dumped, but not defined there.
2775
2776 After the section name comes another field, a number, which for common
2777 symbols is the alignment and for other symbol is the size. Finally
2778 the symbol's name is displayed.
2779
2780 The flag characters are divided into 7 groups as follows:
2781 @table @code
2782 @item l
2783 @itemx g
2784 @itemx u
2785 @itemx !
2786 The symbol is a local (l), global (g), unique global (u), neither
2787 global nor local (a space) or both global and local (!). A
2788 symbol can be neither local or global for a variety of reasons, e.g.,
2789 because it is used for debugging, but it is probably an indication of
2790 a bug if it is ever both local and global. Unique global symbols are
2791 a GNU extension to the standard set of ELF symbol bindings. For such
2792 a symbol the dynamic linker will make sure that in the entire process
2793 there is just one symbol with this name and type in use.
2794
2795 @item w
2796 The symbol is weak (w) or strong (a space).
2797
2798 @item C
2799 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2800
2801 @item W
2802 The symbol is a warning (W) or a normal symbol (a space). A warning
2803 symbol's name is a message to be displayed if the symbol following the
2804 warning symbol is ever referenced.
2805
2806 @item I
2807 @item i
2808 The symbol is an indirect reference to another symbol (I), a function
2809 to be evaluated during reloc processing (i) or a normal symbol (a
2810 space).
2811
2812 @item d
2813 @itemx D
2814 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2815 normal symbol (a space).
2816
2817 @item F
2818 @item f
2819 @item O
2820 The symbol is the name of a function (F) or a file (f) or an object
2821 (O) or just a normal symbol (a space).
2822 @end table
2823
2824 @item -T
2825 @itemx --dynamic-syms
2826 @cindex dynamic symbol table entries, printing
2827 Print the dynamic symbol table entries of the file. This is only
2828 meaningful for dynamic objects, such as certain types of shared
2829 libraries. This is similar to the information provided by the @samp{nm}
2830 program when given the @option{-D} (@option{--dynamic}) option.
2831
2832 The output format is similar to that produced by the @option{--syms}
2833 option, except that an extra field is inserted before the symbol's
2834 name, giving the version information associated with the symbol.
2835 If the version is the default version to be used when resolving
2836 unversioned references to the symbol then it's displayed as is,
2837 otherwise it's put into parentheses.
2838
2839 @item --special-syms
2840 When displaying symbols include those which the target considers to be
2841 special in some way and which would not normally be of interest to the
2842 user.
2843
2844 @item -V
2845 @itemx --version
2846 Print the version number of @command{objdump} and exit.
2847
2848 @item -x
2849 @itemx --all-headers
2850 @cindex all header information, object file
2851 @cindex header information, all
2852 Display all available header information, including the symbol table and
2853 relocation entries. Using @option{-x} is equivalent to specifying all of
2854 @option{-a -f -h -p -r -t}.
2855
2856 @item -w
2857 @itemx --wide
2858 @cindex wide output, printing
2859 Format some lines for output devices that have more than 80 columns.
2860 Also do not truncate symbol names when they are displayed.
2861
2862 @item -z
2863 @itemx --disassemble-zeroes
2864 Normally the disassembly output will skip blocks of zeroes. This
2865 option directs the disassembler to disassemble those blocks, just like
2866 any other data.
2867 @end table
2868
2869 @c man end
2870
2871 @ignore
2872 @c man begin SEEALSO objdump
2873 nm(1), readelf(1), and the Info entries for @file{binutils}.
2874 @c man end
2875 @end ignore
2876
2877 @node ranlib
2878 @chapter ranlib
2879
2880 @kindex ranlib
2881 @cindex archive contents
2882 @cindex symbol index
2883
2884 @c man title ranlib generate an index to an archive
2885
2886 @smallexample
2887 @c man begin SYNOPSIS ranlib
2888 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2889 @c man end
2890 @end smallexample
2891
2892 @c man begin DESCRIPTION ranlib
2893
2894 @command{ranlib} generates an index to the contents of an archive and
2895 stores it in the archive. The index lists each symbol defined by a
2896 member of an archive that is a relocatable object file.
2897
2898 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2899
2900 An archive with such an index speeds up linking to the library and
2901 allows routines in the library to call each other without regard to
2902 their placement in the archive.
2903
2904 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2905 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2906 @xref{ar}.
2907
2908 @c man end
2909
2910 @c man begin OPTIONS ranlib
2911
2912 @table @env
2913 @item -h
2914 @itemx -H
2915 @itemx --help
2916 Show usage information for @command{ranlib}.
2917
2918 @item -v
2919 @itemx -V
2920 @itemx --version
2921 Show the version number of @command{ranlib}.
2922
2923 @item -D
2924 @cindex deterministic archives
2925 @kindex --enable-deterministic-archives
2926 Operate in @emph{deterministic} mode. The symbol map archive member's
2927 header will show zero for the UID, GID, and timestamp. When this
2928 option is used, multiple runs will produce identical output files.
2929
2930 If @file{binutils} was configured with
2931 @option{--enable-deterministic-archives}, then this mode is on by
2932 default. It can be disabled with the @samp{-U} option, described
2933 below.
2934
2935 @item -t
2936 Update the timestamp of the symbol map of an archive.
2937
2938 @item -U
2939 @cindex deterministic archives
2940 @kindex --enable-deterministic-archives
2941 Do @emph{not} operate in @emph{deterministic} mode. This is the
2942 inverse of the @samp{-D} option, above: the archive index will get
2943 actual UID, GID, timestamp, and file mode values.
2944
2945 If @file{binutils} was configured @emph{without}
2946 @option{--enable-deterministic-archives}, then this mode is on by
2947 default.
2948
2949 @end table
2950
2951 @c man end
2952
2953 @ignore
2954 @c man begin SEEALSO ranlib
2955 ar(1), nm(1), and the Info entries for @file{binutils}.
2956 @c man end
2957 @end ignore
2958
2959 @node size
2960 @chapter size
2961
2962 @kindex size
2963 @cindex section sizes
2964
2965 @c man title size list section sizes and total size of binary files
2966
2967 @smallexample
2968 @c man begin SYNOPSIS size
2969 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
2970 [@option{--help}]
2971 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2972 [@option{--common}]
2973 [@option{-t}|@option{--totals}]
2974 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2975 [@var{objfile}@dots{}]
2976 @c man end
2977 @end smallexample
2978
2979 @c man begin DESCRIPTION size
2980
2981 The @sc{gnu} @command{size} utility lists the section sizes and the total
2982 size for each of the binary files @var{objfile} on its argument list.
2983 By default, one line of output is generated for each file or each
2984 module if the file is an archive.
2985
2986 @var{objfile}@dots{} are the files to be examined. If none are
2987 specified, the file @code{a.out} will be used instead.
2988
2989 @c man end
2990
2991 @c man begin OPTIONS size
2992
2993 The command-line options have the following meanings:
2994
2995 @table @env
2996 @item -A
2997 @itemx -B
2998 @itemx -G
2999 @itemx --format=@var{compatibility}
3000 @cindex @command{size} display format
3001 Using one of these options, you can choose whether the output from @sc{gnu}
3002 @command{size} resembles output from System V @command{size} (using @option{-A},
3003 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3004 @option{--format=berkeley}). The default is the one-line format similar to
3005 Berkeley's. Alternatively, you can choose the GNU format output
3006 (using @option{-G}, or @option{--format=gnu}), this is similar to
3007 Berkeley's output format, but sizes are counted differently.
3008 @c Bonus for doc-source readers: you can also say --format=strange (or
3009 @c anything else that starts with 's') for sysv, and --format=boring (or
3010 @c anything else that starts with 'b') for Berkeley.
3011
3012 Here is an example of the Berkeley (default) format of output from
3013 @command{size}:
3014 @smallexample
3015 $ size --format=Berkeley ranlib size
3016 text data bss dec hex filename
3017 294880 81920 11592 388392 5ed28 ranlib
3018 294880 81920 11888 388688 5ee50 size
3019 @end smallexample
3020
3021 The Berkeley style output counts read only data in the @code{text}
3022 column, not in the @code{data} column, the @code{dec} and @code{hex}
3023 columns both display the sum of the @code{text}, @code{data}, and
3024 @code{bss} columns in decimal and hexadecimal respectively.
3025
3026 The GNU format counts read only data in the @code{data} column, not
3027 the @code{text} column, and only displays the sum of the @code{text},
3028 @code{data}, and @code{bss} columns once, in the @code{total} column.
3029 The @option{--radix} option can be used to change the number base for
3030 all columns. Here is the same data displayed with GNU conventions:
3031
3032 @smallexample
3033 $ size --format=GNU ranlib size
3034 text data bss total filename
3035 279880 96920 11592 388392 ranlib
3036 279880 96920 11888 388688 size
3037 @end smallexample
3038
3039 @noindent
3040 This is the same data, but displayed closer to System V conventions:
3041
3042 @smallexample
3043 $ size --format=SysV ranlib size
3044 ranlib :
3045 section size addr
3046 .text 294880 8192
3047 .data 81920 303104
3048 .bss 11592 385024
3049 Total 388392
3050
3051
3052 size :
3053 section size addr
3054 .text 294880 8192
3055 .data 81920 303104
3056 .bss 11888 385024
3057 Total 388688
3058 @end smallexample
3059
3060 @item --help
3061 Show a summary of acceptable arguments and options.
3062
3063 @item -d
3064 @itemx -o
3065 @itemx -x
3066 @itemx --radix=@var{number}
3067 @cindex @command{size} number format
3068 @cindex radix for section sizes
3069 Using one of these options, you can control whether the size of each
3070 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3071 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3072 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3073 values (8, 10, 16) are supported. The total size is always given in two
3074 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3075 octal and hexadecimal if you're using @option{-o}.
3076
3077 @item --common
3078 Print total size of common symbols in each file. When using Berkeley
3079 or GNU format these are included in the bss size.
3080
3081 @item -t
3082 @itemx --totals
3083 Show totals of all objects listed (Berkeley or GNU format mode only).
3084
3085 @item --target=@var{bfdname}
3086 @cindex object code format
3087 Specify that the object-code format for @var{objfile} is
3088 @var{bfdname}. This option may not be necessary; @command{size} can
3089 automatically recognize many formats.
3090 @xref{Target Selection}, for more information.
3091
3092 @item -V
3093 @itemx --version
3094 Display the version number of @command{size}.
3095 @end table
3096
3097 @c man end
3098
3099 @ignore
3100 @c man begin SEEALSO size
3101 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3102 @c man end
3103 @end ignore
3104
3105 @node strings
3106 @chapter strings
3107 @kindex strings
3108 @cindex listings strings
3109 @cindex printing strings
3110 @cindex strings, printing
3111
3112 @c man title strings print the sequences of printable characters in files
3113
3114 @smallexample
3115 @c man begin SYNOPSIS strings
3116 strings [@option{-afovV}] [@option{-}@var{min-len}]
3117 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3118 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3119 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3120 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3121 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3122 [@option{-w}] [@option{--include-all-whitespace}]
3123 [@option{-s}] [@option{--output-separator}@var{sep_string}]
3124 [@option{--help}] [@option{--version}] @var{file}@dots{}
3125 @c man end
3126 @end smallexample
3127
3128 @c man begin DESCRIPTION strings
3129
3130 For each @var{file} given, @sc{gnu} @command{strings} prints the
3131 printable character sequences that are at least 4 characters long (or
3132 the number given with the options below) and are followed by an
3133 unprintable character.
3134
3135 Depending upon how the strings program was configured it will default
3136 to either displaying all the printable sequences that it can find in
3137 each file, or only those sequences that are in loadable, initialized
3138 data sections. If the file type is unrecognizable, or if strings is
3139 reading from stdin then it will always display all of the printable
3140 sequences that it can find.
3141
3142 For backwards compatibility any file that occurs after a command-line
3143 option of just @option{-} will also be scanned in full, regardless of
3144 the presence of any @option{-d} option.
3145
3146 @command{strings} is mainly useful for determining the contents of
3147 non-text files.
3148
3149 @c man end
3150
3151 @c man begin OPTIONS strings
3152
3153 @table @env
3154 @item -a
3155 @itemx --all
3156 @itemx -
3157 Scan the whole file, regardless of what sections it contains or
3158 whether those sections are loaded or initialized. Normally this is
3159 the default behaviour, but strings can be configured so that the
3160 @option{-d} is the default instead.
3161
3162 The @option{-} option is position dependent and forces strings to
3163 perform full scans of any file that is mentioned after the @option{-}
3164 on the command line, even if the @option{-d} option has been
3165 specified.
3166
3167 @item -d
3168 @itemx --data
3169 Only print strings from initialized, loaded data sections in the
3170 file. This may reduce the amount of garbage in the output, but it
3171 also exposes the strings program to any security flaws that may be
3172 present in the BFD library used to scan and load sections. Strings
3173 can be configured so that this option is the default behaviour. In
3174 such cases the @option{-a} option can be used to avoid using the BFD
3175 library and instead just print all of the strings found in the file.
3176
3177 @item -f
3178 @itemx --print-file-name
3179 Print the name of the file before each string.
3180
3181 @item --help
3182 Print a summary of the program usage on the standard output and exit.
3183
3184 @item -@var{min-len}
3185 @itemx -n @var{min-len}
3186 @itemx --bytes=@var{min-len}
3187 Print sequences of characters that are at least @var{min-len} characters
3188 long, instead of the default 4.
3189
3190 @item -o
3191 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3192 act like @samp{-t d} instead. Since we can not be compatible with both
3193 ways, we simply chose one.
3194
3195 @item -t @var{radix}
3196 @itemx --radix=@var{radix}
3197 Print the offset within the file before each string. The single
3198 character argument specifies the radix of the offset---@samp{o} for
3199 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3200
3201 @item -e @var{encoding}
3202 @itemx --encoding=@var{encoding}
3203 Select the character encoding of the strings that are to be found.
3204 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3205 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3206 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3207 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3208 littleendian. Useful for finding wide character strings. (@samp{l}
3209 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3210
3211 @item -T @var{bfdname}
3212 @itemx --target=@var{bfdname}
3213 @cindex object code format
3214 Specify an object code format other than your system's default format.
3215 @xref{Target Selection}, for more information.
3216
3217 @item -v
3218 @itemx -V
3219 @itemx --version
3220 Print the program version number on the standard output and exit.
3221
3222 @item -w
3223 @itemx --include-all-whitespace
3224 By default tab and space characters are included in the strings that
3225 are displayed, but other whitespace characters, such a newlines and
3226 carriage returns, are not. The @option{-w} option changes this so
3227 that all whitespace characters are considered to be part of a string.
3228
3229 @item -s
3230 @itemx --output-separator
3231 By default, output strings are delimited by a new-line. This option
3232 allows you to supply any string to be used as the output record
3233 separator. Useful with --include-all-whitespace where strings
3234 may contain new-lines internally.
3235 @end table
3236
3237 @c man end
3238
3239 @ignore
3240 @c man begin SEEALSO strings
3241 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3242 and the Info entries for @file{binutils}.
3243 @c man end
3244 @end ignore
3245
3246 @node strip
3247 @chapter strip
3248
3249 @kindex strip
3250 @cindex removing symbols
3251 @cindex discarding symbols
3252 @cindex symbols, discarding
3253
3254 @c man title strip discard symbols and other data from object files
3255
3256 @smallexample
3257 @c man begin SYNOPSIS strip
3258 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3259 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3260 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3261 [@option{-s}|@option{--strip-all}]
3262 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3263 [@option{--strip-dwo}]
3264 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3265 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3266 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3267 [@option{-w}|@option{--wildcard}]
3268 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3269 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3270 [@option{--keep-section=}@var{sectionpattern}]
3271 [@option{--remove-relocations=}@var{sectionpattern}]
3272 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3273 [@option{-D}|@option{--enable-deterministic-archives}]
3274 [@option{-U}|@option{--disable-deterministic-archives}]
3275 [@option{--keep-file-symbols}]
3276 [@option{--only-keep-debug}]
3277 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3278 [@option{--help}] [@option{--info}]
3279 @var{objfile}@dots{}
3280 @c man end
3281 @end smallexample
3282
3283 @c man begin DESCRIPTION strip
3284
3285 @sc{gnu} @command{strip} discards all symbols from object files
3286 @var{objfile}. The list of object files may include archives.
3287 At least one object file must be given.
3288
3289 @command{strip} modifies the files named in its argument,
3290 rather than writing modified copies under different names.
3291
3292 @c man end
3293
3294 @c man begin OPTIONS strip
3295
3296 @table @env
3297 @item -F @var{bfdname}
3298 @itemx --target=@var{bfdname}
3299 Treat the original @var{objfile} as a file with the object
3300 code format @var{bfdname}, and rewrite it in the same format.
3301 @xref{Target Selection}, for more information.
3302
3303 @item --help
3304 Show a summary of the options to @command{strip} and exit.
3305
3306 @item --info
3307 Display a list showing all architectures and object formats available.
3308
3309 @item -I @var{bfdname}
3310 @itemx --input-target=@var{bfdname}
3311 Treat the original @var{objfile} as a file with the object
3312 code format @var{bfdname}.
3313 @xref{Target Selection}, for more information.
3314
3315 @item -O @var{bfdname}
3316 @itemx --output-target=@var{bfdname}
3317 Replace @var{objfile} with a file in the output format @var{bfdname}.
3318 @xref{Target Selection}, for more information.
3319
3320 @item -R @var{sectionname}
3321 @itemx --remove-section=@var{sectionname}
3322 Remove any section named @var{sectionname} from the output file, in
3323 addition to whatever sections would otherwise be removed. This
3324 option may be given more than once. Note that using this option
3325 inappropriately may make the output file unusable. The wildcard
3326 character @samp{*} may be given at the end of @var{sectionname}. If
3327 so, then any section starting with @var{sectionname} will be removed.
3328
3329 If the first character of @var{sectionpattern} is the exclamation
3330 point (!) then matching sections will not be removed even if an
3331 earlier use of @option{--remove-section} on the same command line
3332 would otherwise remove it. For example:
3333
3334 @smallexample
3335 --remove-section=.text.* --remove-section=!.text.foo
3336 @end smallexample
3337
3338 will remove all sections matching the pattern '.text.*', but will not
3339 remove the section '.text.foo'.
3340
3341 @item --keep-section=@var{sectionpattern}
3342 When removing sections from the output file, keep sections that match
3343 @var{sectionpattern}.
3344
3345 @item --remove-relocations=@var{sectionpattern}
3346 Remove relocations from the output file for any section matching
3347 @var{sectionpattern}. This option may be given more than once. Note
3348 that using this option inappropriately may make the output file
3349 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3350 For example:
3351
3352 @smallexample
3353 --remove-relocations=.text.*
3354 @end smallexample
3355
3356 will remove the relocations for all sections matching the patter
3357 '.text.*'.
3358
3359 If the first character of @var{sectionpattern} is the exclamation
3360 point (!) then matching sections will not have their relocation
3361 removed even if an earlier use of @option{--remove-relocations} on the
3362 same command line would otherwise cause the relocations to be removed.
3363 For example:
3364
3365 @smallexample
3366 --remove-relocations=.text.* --remove-relocations=!.text.foo
3367 @end smallexample
3368
3369 will remove all relocations for sections matching the pattern
3370 '.text.*', but will not remove relocations for the section
3371 '.text.foo'.
3372
3373 @item -s
3374 @itemx --strip-all
3375 Remove all symbols.
3376
3377 @item -g
3378 @itemx -S
3379 @itemx -d
3380 @itemx --strip-debug
3381 Remove debugging symbols only.
3382
3383 @item --strip-dwo
3384 Remove the contents of all DWARF .dwo sections, leaving the
3385 remaining debugging sections and all symbols intact.
3386 See the description of this option in the @command{objcopy} section
3387 for more information.
3388
3389 @item --strip-unneeded
3390 Remove all symbols that are not needed for relocation processing.
3391
3392 @item -K @var{symbolname}
3393 @itemx --keep-symbol=@var{symbolname}
3394 When stripping symbols, keep symbol @var{symbolname} even if it would
3395 normally be stripped. This option may be given more than once.
3396
3397 @item -M
3398 @itemx --merge-notes
3399 @itemx --no-merge-notes
3400 For ELF files, attempt (or do not attempt) to reduce the size of any
3401 SHT_NOTE type sections by removing duplicate notes. The default is to
3402 attempt this reduction unless stripping debug or DWO information.
3403
3404 @item -N @var{symbolname}
3405 @itemx --strip-symbol=@var{symbolname}
3406 Remove symbol @var{symbolname} from the source file. This option may be
3407 given more than once, and may be combined with strip options other than
3408 @option{-K}.
3409
3410 @item -o @var{file}
3411 Put the stripped output in @var{file}, rather than replacing the
3412 existing file. When this argument is used, only one @var{objfile}
3413 argument may be specified.
3414
3415 @item -p
3416 @itemx --preserve-dates
3417 Preserve the access and modification dates of the file.
3418
3419 @item -D
3420 @itemx --enable-deterministic-archives
3421 @cindex deterministic archives
3422 @kindex --enable-deterministic-archives
3423 Operate in @emph{deterministic} mode. When copying archive members
3424 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3425 and use consistent file modes for all files.
3426
3427 If @file{binutils} was configured with
3428 @option{--enable-deterministic-archives}, then this mode is on by default.
3429 It can be disabled with the @samp{-U} option, below.
3430
3431 @item -U
3432 @itemx --disable-deterministic-archives
3433 @cindex deterministic archives
3434 @kindex --enable-deterministic-archives
3435 Do @emph{not} operate in @emph{deterministic} mode. This is the
3436 inverse of the @option{-D} option, above: when copying archive members
3437 and writing the archive index, use their actual UID, GID, timestamp,
3438 and file mode values.
3439
3440 This is the default unless @file{binutils} was configured with
3441 @option{--enable-deterministic-archives}.
3442
3443 @item -w
3444 @itemx --wildcard
3445 Permit regular expressions in @var{symbolname}s used in other command
3446 line options. The question mark (?), asterisk (*), backslash (\) and
3447 square brackets ([]) operators can be used anywhere in the symbol
3448 name. If the first character of the symbol name is the exclamation
3449 point (!) then the sense of the switch is reversed for that symbol.
3450 For example:
3451
3452 @smallexample
3453 -w -K !foo -K fo*
3454 @end smallexample
3455
3456 would cause strip to only keep symbols that start with the letters
3457 ``fo'', but to discard the symbol ``foo''.
3458
3459 @item -x
3460 @itemx --discard-all
3461 Remove non-global symbols.
3462
3463 @item -X
3464 @itemx --discard-locals
3465 Remove compiler-generated local symbols.
3466 (These usually start with @samp{L} or @samp{.}.)
3467
3468 @item --keep-file-symbols
3469 When stripping a file, perhaps with @option{--strip-debug} or
3470 @option{--strip-unneeded}, retain any symbols specifying source file names,
3471 which would otherwise get stripped.
3472
3473 @item --only-keep-debug
3474 Strip a file, emptying the contents of any sections that would not be
3475 stripped by @option{--strip-debug} and leaving the debugging sections
3476 intact. In ELF files, this preserves all the note sections in the
3477 output as well.
3478
3479 Note - the section headers of the stripped sections are preserved,
3480 including their sizes, but the contents of the section are discarded.
3481 The section headers are preserved so that other tools can match up the
3482 debuginfo file with the real executable, even if that executable has
3483 been relocated to a different address space.
3484
3485 The intention is that this option will be used in conjunction with
3486 @option{--add-gnu-debuglink} to create a two part executable. One a
3487 stripped binary which will occupy less space in RAM and in a
3488 distribution and the second a debugging information file which is only
3489 needed if debugging abilities are required. The suggested procedure
3490 to create these files is as follows:
3491
3492 @enumerate
3493 @item Link the executable as normal. Assuming that it is called
3494 @code{foo} then...
3495 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3496 create a file containing the debugging info.
3497 @item Run @code{objcopy --strip-debug foo} to create a
3498 stripped executable.
3499 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3500 to add a link to the debugging info into the stripped executable.
3501 @end enumerate
3502
3503 Note---the choice of @code{.dbg} as an extension for the debug info
3504 file is arbitrary. Also the @code{--only-keep-debug} step is
3505 optional. You could instead do this:
3506
3507 @enumerate
3508 @item Link the executable as normal.
3509 @item Copy @code{foo} to @code{foo.full}
3510 @item Run @code{strip --strip-debug foo}
3511 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3512 @end enumerate
3513
3514 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3515 full executable. It does not have to be a file created by the
3516 @option{--only-keep-debug} switch.
3517
3518 Note---this switch is only intended for use on fully linked files. It
3519 does not make sense to use it on object files where the debugging
3520 information may be incomplete. Besides the gnu_debuglink feature
3521 currently only supports the presence of one filename containing
3522 debugging information, not multiple filenames on a one-per-object-file
3523 basis.
3524
3525 @item -V
3526 @itemx --version
3527 Show the version number for @command{strip}.
3528
3529 @item -v
3530 @itemx --verbose
3531 Verbose output: list all object files modified. In the case of
3532 archives, @samp{strip -v} lists all members of the archive.
3533 @end table
3534
3535 @c man end
3536
3537 @ignore
3538 @c man begin SEEALSO strip
3539 the Info entries for @file{binutils}.
3540 @c man end
3541 @end ignore
3542
3543 @node c++filt, addr2line, strip, Top
3544 @chapter c++filt
3545
3546 @kindex c++filt
3547 @cindex demangling C++ symbols
3548
3549 @c man title cxxfilt demangle C++ and Java symbols
3550
3551 @smallexample
3552 @c man begin SYNOPSIS cxxfilt
3553 c++filt [@option{-_}|@option{--strip-underscore}]
3554 [@option{-n}|@option{--no-strip-underscore}]
3555 [@option{-p}|@option{--no-params}]
3556 [@option{-t}|@option{--types}]
3557 [@option{-i}|@option{--no-verbose}]
3558 [@option{-r}|@option{--no-recurse-limit}]
3559 [@option{-R}|@option{--recurse-limit}]
3560 [@option{-s} @var{format}|@option{--format=}@var{format}]
3561 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3562 @c man end
3563 @end smallexample
3564
3565 @c man begin DESCRIPTION cxxfilt
3566
3567 @kindex cxxfilt
3568 The C++ and Java languages provide function overloading, which means
3569 that you can write many functions with the same name, providing that
3570 each function takes parameters of different types. In order to be
3571 able to distinguish these similarly named functions C++ and Java
3572 encode them into a low-level assembler name which uniquely identifies
3573 each different version. This process is known as @dfn{mangling}. The
3574 @command{c++filt}
3575 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3576 MS-DOS this program is named @command{CXXFILT}.}
3577 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3578 names into user-level names so that they can be read.
3579
3580 Every alphanumeric word (consisting of letters, digits, underscores,
3581 dollars, or periods) seen in the input is a potential mangled name.
3582 If the name decodes into a C++ name, the C++ name replaces the
3583 low-level name in the output, otherwise the original word is output.
3584 In this way you can pass an entire assembler source file, containing
3585 mangled names, through @command{c++filt} and see the same source file
3586 containing demangled names.
3587
3588 You can also use @command{c++filt} to decipher individual symbols by
3589 passing them on the command line:
3590
3591 @example
3592 c++filt @var{symbol}
3593 @end example
3594
3595 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3596 names from the standard input instead. All the results are printed on
3597 the standard output. The difference between reading names from the
3598 command line versus reading names from the standard input is that
3599 command-line arguments are expected to be just mangled names and no
3600 checking is performed to separate them from surrounding text. Thus
3601 for example:
3602
3603 @smallexample
3604 c++filt -n _Z1fv
3605 @end smallexample
3606
3607 will work and demangle the name to ``f()'' whereas:
3608
3609 @smallexample
3610 c++filt -n _Z1fv,
3611 @end smallexample
3612
3613 will not work. (Note the extra comma at the end of the mangled
3614 name which makes it invalid). This command however will work:
3615
3616 @smallexample
3617 echo _Z1fv, | c++filt -n
3618 @end smallexample
3619
3620 and will display ``f(),'', i.e., the demangled name followed by a
3621 trailing comma. This behaviour is because when the names are read
3622 from the standard input it is expected that they might be part of an
3623 assembler source file where there might be extra, extraneous
3624 characters trailing after a mangled name. For example:
3625
3626 @smallexample
3627 .type _Z1fv, @@function
3628 @end smallexample
3629
3630 @c man end
3631
3632 @c man begin OPTIONS cxxfilt
3633
3634 @table @env
3635 @item -_
3636 @itemx --strip-underscore
3637 On some systems, both the C and C++ compilers put an underscore in front
3638 of every name. For example, the C name @code{foo} gets the low-level
3639 name @code{_foo}. This option removes the initial underscore. Whether
3640 @command{c++filt} removes the underscore by default is target dependent.
3641
3642 @item -n
3643 @itemx --no-strip-underscore
3644 Do not remove the initial underscore.
3645
3646 @item -p
3647 @itemx --no-params
3648 When demangling the name of a function, do not display the types of
3649 the function's parameters.
3650
3651 @item -t
3652 @itemx --types
3653 Attempt to demangle types as well as function names. This is disabled
3654 by default since mangled types are normally only used internally in
3655 the compiler, and they can be confused with non-mangled names. For example,
3656 a function called ``a'' treated as a mangled type name would be
3657 demangled to ``signed char''.
3658
3659 @item -i
3660 @itemx --no-verbose
3661 Do not include implementation details (if any) in the demangled
3662 output.
3663
3664 @item -r
3665 @itemx -R
3666 @itemx --recurse-limit
3667 @itemx --no-recurse-limit
3668 @itemx --recursion-limit
3669 @itemx --no-recursion-limit
3670 Enables or disables a limit on the amount of recursion performed
3671 whilst demangling strings. Since the name mangling formats allow for
3672 an inifinite level of recursion it is possible to create strings whose
3673 decoding will exhaust the amount of stack space available on the host
3674 machine, triggering a memory fault. The limit tries to prevent this
3675 from happening by restricting recursion to 2048 levels of nesting.
3676
3677 The default is for this limit to be enabled, but disabling it may be
3678 necessary in order to demangle truly complicated names. Note however
3679 that if the recursion limit is disabled then stack exhaustion is
3680 possible and any bug reports about such an event will be rejected.
3681
3682 The @option{-r} option is a synonym for the
3683 @option{--no-recurse-limit} option. The @option{-R} option is a
3684 synonym for the @option{--recurse-limit} option.
3685
3686 @item -s @var{format}
3687 @itemx --format=@var{format}
3688 @command{c++filt} can decode various methods of mangling, used by
3689 different compilers. The argument to this option selects which
3690 method it uses:
3691
3692 @table @code
3693 @item auto
3694 Automatic selection based on executable (the default method)
3695 @item gnu
3696 the one used by the @sc{gnu} C++ compiler (g++)
3697 @item lucid
3698 the one used by the Lucid compiler (lcc)
3699 @item arm
3700 the one specified by the C++ Annotated Reference Manual
3701 @item hp
3702 the one used by the HP compiler (aCC)
3703 @item edg
3704 the one used by the EDG compiler
3705 @item gnu-v3
3706 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3707 @item java
3708 the one used by the @sc{gnu} Java compiler (gcj)
3709 @item gnat
3710 the one used by the @sc{gnu} Ada compiler (GNAT).
3711 @end table
3712
3713 @item --help
3714 Print a summary of the options to @command{c++filt} and exit.
3715
3716 @item --version
3717 Print the version number of @command{c++filt} and exit.
3718 @end table
3719
3720 @c man end
3721
3722 @ignore
3723 @c man begin SEEALSO cxxfilt
3724 the Info entries for @file{binutils}.
3725 @c man end
3726 @end ignore
3727
3728 @quotation
3729 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3730 user interface are subject to change in future releases. In particular,
3731 a command-line option may be required in the future to decode a name
3732 passed as an argument on the command line; in other words,
3733
3734 @example
3735 c++filt @var{symbol}
3736 @end example
3737
3738 @noindent
3739 may in a future release become
3740
3741 @example
3742 c++filt @var{option} @var{symbol}
3743 @end example
3744 @end quotation
3745
3746 @node addr2line
3747 @chapter addr2line
3748
3749 @kindex addr2line
3750 @cindex address to file name and line number
3751
3752 @c man title addr2line convert addresses into file names and line numbers
3753
3754 @smallexample
3755 @c man begin SYNOPSIS addr2line
3756 addr2line [@option{-a}|@option{--addresses}]
3757 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3758 [@option{-C}|@option{--demangle}[=@var{style}]]
3759 [@option{-r}|@option{--no-recurse-limit}]
3760 [@option{-R}|@option{--recurse-limit}]
3761 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3762 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3763 [@option{-i}|@option{--inlines}]
3764 [@option{-p}|@option{--pretty-print}]
3765 [@option{-j}|@option{--section=}@var{name}]
3766 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3767 [addr addr @dots{}]
3768 @c man end
3769 @end smallexample
3770
3771 @c man begin DESCRIPTION addr2line
3772
3773 @command{addr2line} translates addresses into file names and line numbers.
3774 Given an address in an executable or an offset in a section of a relocatable
3775 object, it uses the debugging information to figure out which file name and
3776 line number are associated with it.
3777
3778 The executable or relocatable object to use is specified with the @option{-e}
3779 option. The default is the file @file{a.out}. The section in the relocatable
3780 object to use is specified with the @option{-j} option.
3781
3782 @command{addr2line} has two modes of operation.
3783
3784 In the first, hexadecimal addresses are specified on the command line,
3785 and @command{addr2line} displays the file name and line number for each
3786 address.
3787
3788 In the second, @command{addr2line} reads hexadecimal addresses from
3789 standard input, and prints the file name and line number for each
3790 address on standard output. In this mode, @command{addr2line} may be used
3791 in a pipe to convert dynamically chosen addresses.
3792
3793 The format of the output is @samp{FILENAME:LINENO}. By default
3794 each input address generates one line of output.
3795
3796 Two options can generate additional lines before each
3797 @samp{FILENAME:LINENO} line (in that order).
3798
3799 If the @option{-a} option is used then a line with the input address
3800 is displayed.
3801
3802 If the @option{-f} option is used, then a line with the
3803 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3804 containing the address.
3805
3806 One option can generate additional lines after the
3807 @samp{FILENAME:LINENO} line.
3808
3809 If the @option{-i} option is used and the code at the given address is
3810 present there because of inlining by the compiler then additional
3811 lines are displayed afterwards. One or two extra lines (if the
3812 @option{-f} option is used) are displayed for each inlined function.
3813
3814 Alternatively if the @option{-p} option is used then each input
3815 address generates a single, long, output line containing the address,
3816 the function name, the file name and the line number. If the
3817 @option{-i} option has also been used then any inlined functions will
3818 be displayed in the same manner, but on separate lines, and prefixed
3819 by the text @samp{(inlined by)}.
3820
3821 If the file name or function name can not be determined,
3822 @command{addr2line} will print two question marks in their place. If the
3823 line number can not be determined, @command{addr2line} will print 0.
3824
3825 @c man end
3826
3827 @c man begin OPTIONS addr2line
3828
3829 The long and short forms of options, shown here as alternatives, are
3830 equivalent.
3831
3832 @table @env
3833 @item -a
3834 @itemx --addresses
3835 Display the address before the function name, file and line number
3836 information. The address is printed with a @samp{0x} prefix to easily
3837 identify it.
3838
3839 @item -b @var{bfdname}
3840 @itemx --target=@var{bfdname}
3841 @cindex object code format
3842 Specify that the object-code format for the object files is
3843 @var{bfdname}.
3844
3845 @item -C
3846 @itemx --demangle[=@var{style}]
3847 @cindex demangling in objdump
3848 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3849 Besides removing any initial underscore prepended by the system, this
3850 makes C++ function names readable. Different compilers have different
3851 mangling styles. The optional demangling style argument can be used to
3852 choose an appropriate demangling style for your compiler. @xref{c++filt},
3853 for more information on demangling.
3854
3855 @item -e @var{filename}
3856 @itemx --exe=@var{filename}
3857 Specify the name of the executable for which addresses should be
3858 translated. The default file is @file{a.out}.
3859
3860 @item -f
3861 @itemx --functions
3862 Display function names as well as file and line number information.
3863
3864 @item -s
3865 @itemx --basenames
3866 Display only the base of each file name.
3867
3868 @item -i
3869 @itemx --inlines
3870 If the address belongs to a function that was inlined, the source
3871 information for all enclosing scopes back to the first non-inlined
3872 function will also be printed. For example, if @code{main} inlines
3873 @code{callee1} which inlines @code{callee2}, and address is from
3874 @code{callee2}, the source information for @code{callee1} and @code{main}
3875 will also be printed.
3876
3877 @item -j
3878 @itemx --section
3879 Read offsets relative to the specified section instead of absolute addresses.
3880
3881 @item -p
3882 @itemx --pretty-print
3883 Make the output more human friendly: each location are printed on one line.
3884 If option @option{-i} is specified, lines for all enclosing scopes are
3885 prefixed with @samp{(inlined by)}.
3886
3887 @item -r
3888 @itemx -R
3889 @itemx --recurse-limit
3890 @itemx --no-recurse-limit
3891 @itemx --recursion-limit
3892 @itemx --no-recursion-limit
3893 Enables or disables a limit on the amount of recursion performed
3894 whilst demangling strings. Since the name mangling formats allow for
3895 an inifinite level of recursion it is possible to create strings whose
3896 decoding will exhaust the amount of stack space available on the host
3897 machine, triggering a memory fault. The limit tries to prevent this
3898 from happening by restricting recursion to 2048 levels of nesting.
3899
3900 The default is for this limit to be enabled, but disabling it may be
3901 necessary in order to demangle truly complicated names. Note however
3902 that if the recursion limit is disabled then stack exhaustion is
3903 possible and any bug reports about such an event will be rejected.
3904
3905 The @option{-r} option is a synonym for the
3906 @option{--no-recurse-limit} option. The @option{-R} option is a
3907 synonym for the @option{--recurse-limit} option.
3908
3909 Note this option is only effective if the @option{-C} or
3910 @option{--demangle} option has been enabled.
3911
3912 @end table
3913
3914 @c man end
3915
3916 @ignore
3917 @c man begin SEEALSO addr2line
3918 Info entries for @file{binutils}.
3919 @c man end
3920 @end ignore
3921
3922 @node windmc
3923 @chapter windmc
3924
3925 @command{windmc} may be used to generator Windows message resources.
3926
3927 @quotation
3928 @emph{Warning:} @command{windmc} is not always built as part of the binary
3929 utilities, since it is only useful for Windows targets.
3930 @end quotation
3931
3932 @c man title windmc generates Windows message resources
3933
3934 @smallexample
3935 @c man begin SYNOPSIS windmc
3936 windmc [options] input-file
3937 @c man end
3938 @end smallexample
3939
3940 @c man begin DESCRIPTION windmc
3941
3942 @command{windmc} reads message definitions from an input file (.mc) and
3943 translate them into a set of output files. The output files may be of
3944 four kinds:
3945
3946 @table @code
3947 @item h
3948 A C header file containing the message definitions.
3949
3950 @item rc
3951 A resource file compilable by the @command{windres} tool.
3952
3953 @item bin
3954 One or more binary files containing the resource data for a specific
3955 message language.
3956
3957 @item dbg
3958 A C include file that maps message id's to their symbolic name.
3959 @end table
3960
3961 The exact description of these different formats is available in
3962 documentation from Microsoft.
3963
3964 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3965 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3966 Windows Message Compiler.
3967
3968 @c man end
3969
3970 @c man begin OPTIONS windmc
3971
3972 @table @env
3973 @item -a
3974 @itemx --ascii_in
3975 Specifies that the input file specified is ASCII. This is the default
3976 behaviour.
3977
3978 @item -A
3979 @itemx --ascii_out
3980 Specifies that messages in the output @code{bin} files should be in ASCII
3981 format.
3982
3983 @item -b
3984 @itemx --binprefix
3985 Specifies that @code{bin} filenames should have to be prefixed by the
3986 basename of the source file.
3987
3988 @item -c
3989 @itemx --customflag
3990 Sets the customer bit in all message id's.
3991
3992 @item -C @var{codepage}
3993 @itemx --codepage_in @var{codepage}
3994 Sets the default codepage to be used to convert input file to UTF16. The
3995 default is ocdepage 1252.
3996
3997 @item -d
3998 @itemx --decimal_values
3999 Outputs the constants in the header file in decimal. Default is using
4000 hexadecimal output.
4001
4002 @item -e @var{ext}
4003 @itemx --extension @var{ext}
4004 The extension for the header file. The default is .h extension.
4005
4006 @item -F @var{target}
4007 @itemx --target @var{target}
4008 Specify the BFD format to use for a bin file as output. This
4009 is a BFD target name; you can use the @option{--help} option to see a list
4010 of supported targets. Normally @command{windmc} will use the default
4011 format, which is the first one listed by the @option{--help} option.
4012 @ifclear man
4013 @ref{Target Selection}.
4014 @end ifclear
4015
4016 @item -h @var{path}
4017 @itemx --headerdir @var{path}
4018 The target directory of the generated header file. The default is the
4019 current directory.
4020
4021 @item -H
4022 @itemx --help
4023 Displays a list of command-line options and then exits.
4024
4025 @item -m @var{characters}
4026 @itemx --maxlength @var{characters}
4027 Instructs @command{windmc} to generate a warning if the length
4028 of any message exceeds the number specified.
4029
4030 @item -n
4031 @itemx --nullterminate
4032 Terminate message text in @code{bin} files by zero. By default they are
4033 terminated by CR/LF.
4034
4035 @item -o
4036 @itemx --hresult_use
4037 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4038 file, using HRESULT definitions. Status codes are used if the flag is not
4039 specified.
4040
4041 @item -O @var{codepage}
4042 @itemx --codepage_out @var{codepage}
4043 Sets the default codepage to be used to output text files. The default
4044 is ocdepage 1252.
4045
4046 @item -r @var{path}
4047 @itemx --rcdir @var{path}
4048 The target directory for the generated @code{rc} script and the generated
4049 @code{bin} files that the resource compiler script includes. The default
4050 is the current directory.
4051
4052 @item -u
4053 @itemx --unicode_in
4054 Specifies that the input file is UTF16.
4055
4056 @item -U
4057 @itemx --unicode_out
4058 Specifies that messages in the output @code{bin} file should be in UTF16
4059 format. This is the default behaviour.
4060
4061 @item -v
4062 @item --verbose
4063 Enable verbose mode.
4064
4065 @item -V
4066 @item --version
4067 Prints the version number for @command{windmc}.
4068
4069 @item -x @var{path}
4070 @itemx --xdgb @var{path}
4071 The path of the @code{dbg} C include file that maps message id's to the
4072 symbolic name. No such file is generated without specifying the switch.
4073 @end table
4074
4075 @c man end
4076
4077 @ignore
4078 @c man begin SEEALSO windmc
4079 the Info entries for @file{binutils}.
4080 @c man end
4081 @end ignore
4082
4083 @node windres
4084 @chapter windres
4085
4086 @command{windres} may be used to manipulate Windows resources.
4087
4088 @quotation
4089 @emph{Warning:} @command{windres} is not always built as part of the binary
4090 utilities, since it is only useful for Windows targets.
4091 @end quotation
4092
4093 @c man title windres manipulate Windows resources
4094
4095 @smallexample
4096 @c man begin SYNOPSIS windres
4097 windres [options] [input-file] [output-file]
4098 @c man end
4099 @end smallexample
4100
4101 @c man begin DESCRIPTION windres
4102
4103 @command{windres} reads resources from an input file and copies them into
4104 an output file. Either file may be in one of three formats:
4105
4106 @table @code
4107 @item rc
4108 A text format read by the Resource Compiler.
4109
4110 @item res
4111 A binary format generated by the Resource Compiler.
4112
4113 @item coff
4114 A COFF object or executable.
4115 @end table
4116
4117 The exact description of these different formats is available in
4118 documentation from Microsoft.
4119
4120 When @command{windres} converts from the @code{rc} format to the @code{res}
4121 format, it is acting like the Windows Resource Compiler. When
4122 @command{windres} converts from the @code{res} format to the @code{coff}
4123 format, it is acting like the Windows @code{CVTRES} program.
4124
4125 When @command{windres} generates an @code{rc} file, the output is similar
4126 but not identical to the format expected for the input. When an input
4127 @code{rc} file refers to an external filename, an output @code{rc} file
4128 will instead include the file contents.
4129
4130 If the input or output format is not specified, @command{windres} will
4131 guess based on the file name, or, for the input file, the file contents.
4132 A file with an extension of @file{.rc} will be treated as an @code{rc}
4133 file, a file with an extension of @file{.res} will be treated as a
4134 @code{res} file, and a file with an extension of @file{.o} or
4135 @file{.exe} will be treated as a @code{coff} file.
4136
4137 If no output file is specified, @command{windres} will print the resources
4138 in @code{rc} format to standard output.
4139
4140 The normal use is for you to write an @code{rc} file, use @command{windres}
4141 to convert it to a COFF object file, and then link the COFF file into
4142 your application. This will make the resources described in the
4143 @code{rc} file available to Windows.
4144
4145 @c man end
4146
4147 @c man begin OPTIONS windres
4148
4149 @table @env
4150 @item -i @var{filename}
4151 @itemx --input @var{filename}
4152 The name of the input file. If this option is not used, then
4153 @command{windres} will use the first non-option argument as the input file
4154 name. If there are no non-option arguments, then @command{windres} will
4155 read from standard input. @command{windres} can not read a COFF file from
4156 standard input.
4157
4158 @item -o @var{filename}
4159 @itemx --output @var{filename}
4160 The name of the output file. If this option is not used, then
4161 @command{windres} will use the first non-option argument, after any used
4162 for the input file name, as the output file name. If there is no
4163 non-option argument, then @command{windres} will write to standard output.
4164 @command{windres} can not write a COFF file to standard output. Note,
4165 for compatibility with @command{rc} the option @option{-fo} is also
4166 accepted, but its use is not recommended.
4167
4168 @item -J @var{format}
4169 @itemx --input-format @var{format}
4170 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4171 @samp{coff}. If no input format is specified, @command{windres} will
4172 guess, as described above.
4173
4174 @item -O @var{format}
4175 @itemx --output-format @var{format}
4176 The output format to generate. @var{format} may be @samp{res},
4177 @samp{rc}, or @samp{coff}. If no output format is specified,
4178 @command{windres} will guess, as described above.
4179
4180 @item -F @var{target}
4181 @itemx --target @var{target}
4182 Specify the BFD format to use for a COFF file as input or output. This
4183 is a BFD target name; you can use the @option{--help} option to see a list
4184 of supported targets. Normally @command{windres} will use the default
4185 format, which is the first one listed by the @option{--help} option.
4186 @ifclear man
4187 @ref{Target Selection}.
4188 @end ifclear
4189
4190 @item --preprocessor @var{program}
4191 When @command{windres} reads an @code{rc} file, it runs it through the C
4192 preprocessor first. This option may be used to specify the preprocessor
4193 to use, including any leading arguments. The default preprocessor
4194 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
4195
4196 @item --preprocessor-arg @var{option}
4197 When @command{windres} reads an @code{rc} file, it runs it through
4198 the C preprocessor first. This option may be used to specify additional
4199 text to be passed to preprocessor on its command line.
4200 This option can be used multiple times to add multiple options to the
4201 preprocessor command line.
4202
4203 @item -I @var{directory}
4204 @itemx --include-dir @var{directory}
4205 Specify an include directory to use when reading an @code{rc} file.
4206 @command{windres} will pass this to the preprocessor as an @option{-I}
4207 option. @command{windres} will also search this directory when looking for
4208 files named in the @code{rc} file. If the argument passed to this command
4209 matches any of the supported @var{formats} (as described in the @option{-J}
4210 option), it will issue a deprecation warning, and behave just like the
4211 @option{-J} option. New programs should not use this behaviour. If a
4212 directory happens to match a @var{format}, simple prefix it with @samp{./}
4213 to disable the backward compatibility.
4214
4215 @item -D @var{target}
4216 @itemx --define @var{sym}[=@var{val}]
4217 Specify a @option{-D} option to pass to the preprocessor when reading an
4218 @code{rc} file.
4219
4220 @item -U @var{target}
4221 @itemx --undefine @var{sym}
4222 Specify a @option{-U} option to pass to the preprocessor when reading an
4223 @code{rc} file.
4224
4225 @item -r
4226 Ignored for compatibility with rc.
4227
4228 @item -v
4229 Enable verbose mode. This tells you what the preprocessor is if you
4230 didn't specify one.
4231
4232 @item -c @var{val}
4233 @item --codepage @var{val}
4234 Specify the default codepage to use when reading an @code{rc} file.
4235 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4236 codepage code. The valid range is from zero up to 0xffff, but the
4237 validity of the codepage is host and configuration dependent.
4238
4239 @item -l @var{val}
4240 @item --language @var{val}
4241 Specify the default language to use when reading an @code{rc} file.
4242 @var{val} should be a hexadecimal language code. The low eight bits are
4243 the language, and the high eight bits are the sublanguage.
4244
4245 @item --use-temp-file
4246 Use a temporary file to instead of using popen to read the output of
4247 the preprocessor. Use this option if the popen implementation is buggy
4248 on the host (eg., certain non-English language versions of Windows 95 and
4249 Windows 98 are known to have buggy popen where the output will instead
4250 go the console).
4251
4252 @item --no-use-temp-file
4253 Use popen, not a temporary file, to read the output of the preprocessor.
4254 This is the default behaviour.
4255
4256 @item -h
4257 @item --help
4258 Prints a usage summary.
4259
4260 @item -V
4261 @item --version
4262 Prints the version number for @command{windres}.
4263
4264 @item --yydebug
4265 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4266 this will turn on parser debugging.
4267 @end table
4268
4269 @c man end
4270
4271 @ignore
4272 @c man begin SEEALSO windres
4273 the Info entries for @file{binutils}.
4274 @c man end
4275 @end ignore
4276
4277 @node dlltool
4278 @chapter dlltool
4279 @cindex DLL
4280 @kindex dlltool
4281
4282 @command{dlltool} is used to create the files needed to create dynamic
4283 link libraries (DLLs) on systems which understand PE format image
4284 files such as Windows. A DLL contains an export table which contains
4285 information that the runtime loader needs to resolve references from a
4286 referencing program.
4287
4288 The export table is generated by this program by reading in a
4289 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4290 will be in the DLL. A @file{.o} file can contain information in
4291 special @samp{.drectve} sections with export information.
4292
4293 @quotation
4294 @emph{Note:} @command{dlltool} is not always built as part of the
4295 binary utilities, since it is only useful for those targets which
4296 support DLLs.
4297 @end quotation
4298
4299 @c man title dlltool create files needed to build and use DLLs
4300
4301 @smallexample
4302 @c man begin SYNOPSIS dlltool
4303 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4304 [@option{-b}|@option{--base-file} @var{base-file-name}]
4305 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4306 [@option{-z}|@option{--output-def} @var{def-file-name}]
4307 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4308 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4309 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4310 [@option{--exclude-symbols} @var{list}]
4311 [@option{--no-default-excludes}]
4312 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4313 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4314 [@option{-a}|@option{--add-indirect}]
4315 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4316 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4317 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4318 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4319 [@option{--use-nul-prefixed-import-tables}]
4320 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4321 [@option{-i}|@option{--interwork}]
4322 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4323 [@option{-v}|@option{--verbose}]
4324 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4325 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4326 [object-file @dots{}]
4327 @c man end
4328 @end smallexample
4329
4330 @c man begin DESCRIPTION dlltool
4331
4332 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4333 @option{-b} options as well as object files specified on the command
4334 line. It then processes these inputs and if the @option{-e} option has
4335 been specified it creates a exports file. If the @option{-l} option
4336 has been specified it creates a library file and if the @option{-z} option
4337 has been specified it creates a def file. Any or all of the @option{-e},
4338 @option{-l} and @option{-z} options can be present in one invocation of
4339 dlltool.
4340
4341 When creating a DLL, along with the source for the DLL, it is necessary
4342 to have three other files. @command{dlltool} can help with the creation of
4343 these files.
4344
4345 The first file is a @file{.def} file which specifies which functions are
4346 exported from the DLL, which functions the DLL imports, and so on. This
4347 is a text file and can be created by hand, or @command{dlltool} can be used
4348 to create it using the @option{-z} option. In this case @command{dlltool}
4349 will scan the object files specified on its command line looking for
4350 those functions which have been specially marked as being exported and
4351 put entries for them in the @file{.def} file it creates.
4352
4353 In order to mark a function as being exported from a DLL, it needs to
4354 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4355 section of the object file. This can be done in C by using the
4356 asm() operator:
4357
4358 @smallexample
4359 asm (".section .drectve");
4360 asm (".ascii \"-export:my_func\"");
4361
4362 int my_func (void) @{ @dots{} @}
4363 @end smallexample
4364
4365 The second file needed for DLL creation is an exports file. This file
4366 is linked with the object files that make up the body of the DLL and it
4367 handles the interface between the DLL and the outside world. This is a
4368 binary file and it can be created by giving the @option{-e} option to
4369 @command{dlltool} when it is creating or reading in a @file{.def} file.
4370
4371 The third file needed for DLL creation is the library file that programs
4372 will link with in order to access the functions in the DLL (an `import
4373 library'). This file can be created by giving the @option{-l} option to
4374 dlltool when it is creating or reading in a @file{.def} file.
4375
4376 If the @option{-y} option is specified, dlltool generates a delay-import
4377 library that can be used instead of the normal import library to allow
4378 a program to link to the dll only as soon as an imported function is
4379 called for the first time. The resulting executable will need to be
4380 linked to the static delayimp library containing __delayLoadHelper2(),
4381 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4382
4383 @command{dlltool} builds the library file by hand, but it builds the
4384 exports file by creating temporary files containing assembler statements
4385 and then assembling these. The @option{-S} command-line option can be
4386 used to specify the path to the assembler that dlltool will use,
4387 and the @option{-f} option can be used to pass specific flags to that
4388 assembler. The @option{-n} can be used to prevent dlltool from deleting
4389 these temporary assembler files when it is done, and if @option{-n} is
4390 specified twice then this will prevent dlltool from deleting the
4391 temporary object files it used to build the library.
4392
4393 Here is an example of creating a DLL from a source file @samp{dll.c} and
4394 also creating a program (from an object file called @samp{program.o})
4395 that uses that DLL:
4396
4397 @smallexample
4398 gcc -c dll.c
4399 dlltool -e exports.o -l dll.lib dll.o
4400 gcc dll.o exports.o -o dll.dll
4401 gcc program.o dll.lib -o program
4402 @end smallexample
4403
4404
4405 @command{dlltool} may also be used to query an existing import library
4406 to determine the name of the DLL to which it is associated. See the
4407 description of the @option{-I} or @option{--identify} option.
4408
4409 @c man end
4410
4411 @c man begin OPTIONS dlltool
4412
4413 The command-line options have the following meanings:
4414
4415 @table @env
4416
4417 @item -d @var{filename}
4418 @itemx --input-def @var{filename}
4419 @cindex input .def file
4420 Specifies the name of a @file{.def} file to be read in and processed.
4421
4422 @item -b @var{filename}
4423 @itemx --base-file @var{filename}
4424 @cindex base files
4425 Specifies the name of a base file to be read in and processed. The
4426 contents of this file will be added to the relocation section in the
4427 exports file generated by dlltool.
4428
4429 @item -e @var{filename}
4430 @itemx --output-exp @var{filename}
4431 Specifies the name of the export file to be created by dlltool.
4432
4433 @item -z @var{filename}
4434 @itemx --output-def @var{filename}
4435 Specifies the name of the @file{.def} file to be created by dlltool.
4436
4437 @item -l @var{filename}
4438 @itemx --output-lib @var{filename}
4439 Specifies the name of the library file to be created by dlltool.
4440
4441 @item -y @var{filename}
4442 @itemx --output-delaylib @var{filename}
4443 Specifies the name of the delay-import library file to be created by dlltool.
4444
4445 @item --export-all-symbols
4446 Treat all global and weak defined symbols found in the input object
4447 files as symbols to be exported. There is a small list of symbols which
4448 are not exported by default; see the @option{--no-default-excludes}
4449 option. You may add to the list of symbols to not export by using the
4450 @option{--exclude-symbols} option.
4451
4452 @item --no-export-all-symbols
4453 Only export symbols explicitly listed in an input @file{.def} file or in
4454 @samp{.drectve} sections in the input object files. This is the default
4455 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4456 attributes in the source code.
4457
4458 @item --exclude-symbols @var{list}
4459 Do not export the symbols in @var{list}. This is a list of symbol names
4460 separated by comma or colon characters. The symbol names should not
4461 contain a leading underscore. This is only meaningful when
4462 @option{--export-all-symbols} is used.
4463
4464 @item --no-default-excludes
4465 When @option{--export-all-symbols} is used, it will by default avoid
4466 exporting certain special symbols. The current list of symbols to avoid
4467 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4468 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4469 to go ahead and export these special symbols. This is only meaningful
4470 when @option{--export-all-symbols} is used.
4471
4472 @item -S @var{path}
4473 @itemx --as @var{path}
4474 Specifies the path, including the filename, of the assembler to be used
4475 to create the exports file.
4476
4477 @item -f @var{options}
4478 @itemx --as-flags @var{options}
4479 Specifies any specific command-line options to be passed to the
4480 assembler when building the exports file. This option will work even if
4481 the @option{-S} option is not used. This option only takes one argument,
4482 and if it occurs more than once on the command line, then later
4483 occurrences will override earlier occurrences. So if it is necessary to
4484 pass multiple options to the assembler they should be enclosed in
4485 double quotes.
4486
4487 @item -D @var{name}
4488 @itemx --dll-name @var{name}
4489 Specifies the name to be stored in the @file{.def} file as the name of
4490 the DLL when the @option{-e} option is used. If this option is not
4491 present, then the filename given to the @option{-e} option will be
4492 used as the name of the DLL.
4493
4494 @item -m @var{machine}
4495 @itemx -machine @var{machine}
4496 Specifies the type of machine for which the library file should be
4497 built. @command{dlltool} has a built in default type, depending upon how
4498 it was created, but this option can be used to override that. This is
4499 normally only useful when creating DLLs for an ARM processor, when the
4500 contents of the DLL are actually encode using Thumb instructions.
4501
4502 @item -a
4503 @itemx --add-indirect
4504 Specifies that when @command{dlltool} is creating the exports file it
4505 should add a section which allows the exported functions to be
4506 referenced without using the import library. Whatever the hell that
4507 means!
4508
4509 @item -U
4510 @itemx --add-underscore
4511 Specifies that when @command{dlltool} is creating the exports file it
4512 should prepend an underscore to the names of @emph{all} exported symbols.
4513
4514 @item --no-leading-underscore
4515 @item --leading-underscore
4516 Specifies whether standard symbol should be forced to be prefixed, or
4517 not.
4518
4519 @item --add-stdcall-underscore
4520 Specifies that when @command{dlltool} is creating the exports file it
4521 should prepend an underscore to the names of exported @emph{stdcall}
4522 functions. Variable names and non-stdcall function names are not modified.
4523 This option is useful when creating GNU-compatible import libs for third
4524 party DLLs that were built with MS-Windows tools.
4525
4526 @item -k
4527 @itemx --kill-at
4528 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4529 of stdcall functions that will be imported from the DLL. This is
4530 useful when creating an import library for a DLL which exports stdcall
4531 functions but without the usual @samp{@@<number>} symbol name suffix.
4532
4533 This does not change the naming of symbols provided by the import library
4534 to programs linked against it, but only the entries in the import table
4535 (ie the .idata section).
4536
4537 @item -A
4538 @itemx --add-stdcall-alias
4539 Specifies that when @command{dlltool} is creating the exports file it
4540 should add aliases for stdcall symbols without @samp{@@ <number>}
4541 in addition to the symbols with @samp{@@ <number>}.
4542
4543 @item -p
4544 @itemx --ext-prefix-alias @var{prefix}
4545 Causes @command{dlltool} to create external aliases for all DLL
4546 imports with the specified prefix. The aliases are created for both
4547 external and import symbols with no leading underscore.
4548
4549 @item -x
4550 @itemx --no-idata4
4551 Specifies that when @command{dlltool} is creating the exports and library
4552 files it should omit the @code{.idata4} section. This is for compatibility
4553 with certain operating systems.
4554
4555 @item --use-nul-prefixed-import-tables
4556 Specifies that when @command{dlltool} is creating the exports and library
4557 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4558 element. This emulates old gnu import library generation of
4559 @code{dlltool}. By default this option is turned off.
4560
4561 @item -c
4562 @itemx --no-idata5
4563 Specifies that when @command{dlltool} is creating the exports and library
4564 files it should omit the @code{.idata5} section. This is for compatibility
4565 with certain operating systems.
4566
4567 @item -I @var{filename}
4568 @itemx --identify @var{filename}
4569 Specifies that @command{dlltool} should inspect the import library
4570 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4571 of the associated DLL(s). This can be performed in addition to any
4572 other operations indicated by the other options and arguments.
4573 @command{dlltool} fails if the import library does not exist or is not
4574 actually an import library. See also @option{--identify-strict}.
4575
4576 @item --identify-strict
4577 Modifies the behavior of the @option{--identify} option, such
4578 that an error is reported if @var{filename} is associated with
4579 more than one DLL.
4580
4581 @item -i
4582 @itemx --interwork
4583 Specifies that @command{dlltool} should mark the objects in the library
4584 file and exports file that it produces as supporting interworking
4585 between ARM and Thumb code.
4586
4587 @item -n
4588 @itemx --nodelete
4589 Makes @command{dlltool} preserve the temporary assembler files it used to
4590 create the exports file. If this option is repeated then dlltool will
4591 also preserve the temporary object files it uses to create the library
4592 file.
4593
4594 @item -t @var{prefix}
4595 @itemx --temp-prefix @var{prefix}
4596 Makes @command{dlltool} use @var{prefix} when constructing the names of
4597 temporary assembler and object files. By default, the temp file prefix
4598 is generated from the pid.
4599
4600 @item -v
4601 @itemx --verbose
4602 Make dlltool describe what it is doing.
4603
4604 @item -h
4605 @itemx --help
4606 Displays a list of command-line options and then exits.
4607
4608 @item -V
4609 @itemx --version
4610 Displays dlltool's version number and then exits.
4611
4612 @end table
4613
4614 @c man end
4615
4616 @menu
4617 * def file format:: The format of the dlltool @file{.def} file
4618 @end menu
4619
4620 @node def file format
4621 @section The format of the @command{dlltool} @file{.def} file
4622
4623 A @file{.def} file contains any number of the following commands:
4624
4625 @table @asis
4626
4627 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4628 The result is going to be named @var{name}@code{.exe}.
4629
4630 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4631 The result is going to be named @var{name}@code{.dll}.
4632 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4633 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4634 details).
4635
4636 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4637 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4638 Declares @var{name1} as an exported symbol from the DLL, with optional
4639 ordinal number @var{integer}, or declares @var{name1} as an alias
4640 (forward) of the function @var{external-name} in the DLL.
4641 If @var{its_name} is specified, this name is used as string in export table.
4642 @var{module-name}.
4643 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4644 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4645 If you want to use LIBRARY as name then you need to quote it.
4646
4647 @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{]} *}
4648 Declares that @var{external-name} or the exported function whose
4649 ordinal number is @var{integer} is to be imported from the file
4650 @var{module-name}. If @var{internal-name} is specified then this is
4651 the name that the imported function will be referred to in the body of
4652 the DLL.
4653 If @var{its_name} is specified, this name is used as string in import table.
4654 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4655 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4656 If you want to use LIBRARY as name then you need to quote it.
4657
4658 @item @code{DESCRIPTION} @var{string}
4659 Puts @var{string} into the output @file{.exp} file in the
4660 @code{.rdata} section.
4661
4662 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4663 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4664 Generates @code{--stack} or @code{--heap}
4665 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4666 section. The linker will see this and act upon it.
4667
4668 @item @code{CODE} @var{attr} @code{+}
4669 @item @code{DATA} @var{attr} @code{+}
4670 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4671 Generates @code{--attr} @var{section-name} @var{attr} in the output
4672 @code{.drectve} section, where @var{attr} is one of @code{READ},
4673 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4674 this and act upon it.
4675
4676 @end table
4677
4678 @ignore
4679 @c man begin SEEALSO dlltool
4680 The Info pages for @file{binutils}.
4681 @c man end
4682 @end ignore
4683
4684 @node readelf
4685 @chapter readelf
4686
4687 @cindex ELF file information
4688 @kindex readelf
4689
4690 @c man title readelf display information about ELF files
4691
4692 @smallexample
4693 @c man begin SYNOPSIS readelf
4694 readelf [@option{-a}|@option{--all}]
4695 [@option{-h}|@option{--file-header}]
4696 [@option{-l}|@option{--program-headers}|@option{--segments}]
4697 [@option{-S}|@option{--section-headers}|@option{--sections}]
4698 [@option{-g}|@option{--section-groups}]
4699 [@option{-t}|@option{--section-details}]
4700 [@option{-e}|@option{--headers}]
4701 [@option{-s}|@option{--syms}|@option{--symbols}]
4702 [@option{--dyn-syms}]
4703 [@option{--demangle@var{=style}}|@option{--no-demangle}]
4704 [@option{--recurse-limit}|@option{--no-recurse-limit}]
4705 [@option{-n}|@option{--notes}]
4706 [@option{-r}|@option{--relocs}]
4707 [@option{-u}|@option{--unwind}]
4708 [@option{-d}|@option{--dynamic}]
4709 [@option{-V}|@option{--version-info}]
4710 [@option{-A}|@option{--arch-specific}]
4711 [@option{-D}|@option{--use-dynamic}]
4712 [@option{-L}|@option{--lint}|@option{--enable-checks}]
4713 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4714 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4715 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4716 [@option{-z}|@option{--decompress}]
4717 [@option{-c}|@option{--archive-index}]
4718 [@option{-w[lLiaprmfFsoORtUuTgAckK]}|
4719 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]]
4720 [@option{--dwarf-depth=@var{n}}]
4721 [@option{--dwarf-start=@var{n}}]
4722 [@option{--ctf=}@var{section}]
4723 [@option{--ctf-parent=}@var{section}]
4724 [@option{--ctf-symbols=}@var{section}]
4725 [@option{--ctf-strings=}@var{section}]
4726 [@option{-I}|@option{--histogram}]
4727 [@option{-v}|@option{--version}]
4728 [@option{-W}|@option{--wide}]
4729 [@option{-T}|@option{--silent-truncation}]
4730 [@option{-H}|@option{--help}]
4731 @var{elffile}@dots{}
4732 @c man end
4733 @end smallexample
4734
4735 @c man begin DESCRIPTION readelf
4736
4737 @command{readelf} displays information about one or more ELF format object
4738 files. The options control what particular information to display.
4739
4740 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4741 64-bit ELF files are supported, as are archives containing ELF files.
4742
4743 This program performs a similar function to @command{objdump} but it
4744 goes into more detail and it exists independently of the @sc{bfd}
4745 library, so if there is a bug in @sc{bfd} then readelf will not be
4746 affected.
4747
4748 @c man end
4749
4750 @c man begin OPTIONS readelf
4751
4752 The long and short forms of options, shown here as alternatives, are
4753 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4754 given.
4755
4756 @table @env
4757 @item -a
4758 @itemx --all
4759 Equivalent to specifying @option{--file-header},
4760 @option{--program-headers}, @option{--sections}, @option{--symbols},
4761 @option{--relocs}, @option{--dynamic}, @option{--notes},
4762 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4763 @option{--section-groups} and @option{--histogram}.
4764
4765 Note - this option does not enable @option{--use-dynamic} itself, so
4766 if that option is not present on the command line then dynamic symbols
4767 and dynamic relocs will not be displayed.
4768
4769 @item -h
4770 @itemx --file-header
4771 @cindex ELF file header information
4772 Displays the information contained in the ELF header at the start of the
4773 file.
4774
4775 @item -l
4776 @itemx --program-headers
4777 @itemx --segments
4778 @cindex ELF program header information
4779 @cindex ELF segment information
4780 Displays the information contained in the file's segment headers, if it
4781 has any.
4782
4783 @item -S
4784 @itemx --sections
4785 @itemx --section-headers
4786 @cindex ELF section information
4787 Displays the information contained in the file's section headers, if it
4788 has any.
4789
4790 @item -g
4791 @itemx --section-groups
4792 @cindex ELF section group information
4793 Displays the information contained in the file's section groups, if it
4794 has any.
4795
4796 @item -t
4797 @itemx --section-details
4798 @cindex ELF section information
4799 Displays the detailed section information. Implies @option{-S}.
4800
4801 @item -s
4802 @itemx --symbols
4803 @itemx --syms
4804 @cindex ELF symbol table information
4805 Displays the entries in symbol table section of the file, if it has one.
4806 If a symbol has version information associated with it then this is
4807 displayed as well. The version string is displayed as a suffix to the
4808 symbol name, preceded by an @@ character. For example
4809 @samp{foo@@VER_1}. If the version is the default version to be used
4810 when resolving unversioned references to the symbol then it is
4811 displayed as a suffix preceded by two @@ characters. For example
4812 @samp{foo@@@@VER_2}.
4813
4814 @item --dyn-syms
4815 @cindex ELF dynamic symbol table information
4816 Displays the entries in dynamic symbol table section of the file, if it
4817 has one. The output format is the same as the format used by the
4818 @option{--syms} option.
4819
4820 @item -C
4821 @itemx --demangle[=@var{style}]
4822 @cindex demangling in nm
4823 Decode (@dfn{demangle}) low-level symbol names into user-level names.
4824 This makes C++ function names readable. Different compilers have
4825 different mangling styles. The optional demangling style argument can
4826 be used to choose an appropriate demangling style for your
4827 compiler. @xref{c++filt}, for more information on demangling.
4828
4829 @item --no-demangle
4830 Do not demangle low-level symbol names. This is the default.
4831
4832 @item --recurse-limit
4833 @itemx --no-recurse-limit
4834 @itemx --recursion-limit
4835 @itemx --no-recursion-limit
4836 Enables or disables a limit on the amount of recursion performed
4837 whilst demangling strings. Since the name mangling formats allow for
4838 an inifinite level of recursion it is possible to create strings whose
4839 decoding will exhaust the amount of stack space available on the host
4840 machine, triggering a memory fault. The limit tries to prevent this
4841 from happening by restricting recursion to 2048 levels of nesting.
4842
4843 The default is for this limit to be enabled, but disabling it may be
4844 necessary in order to demangle truly complicated names. Note however
4845 that if the recursion limit is disabled then stack exhaustion is
4846 possible and any bug reports about such an event will be rejected.
4847
4848 @item -e
4849 @itemx --headers
4850 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4851
4852 @item -n
4853 @itemx --notes
4854 @cindex ELF notes
4855 Displays the contents of the NOTE segments and/or sections, if any.
4856
4857 @item -r
4858 @itemx --relocs
4859 @cindex ELF reloc information
4860 Displays the contents of the file's relocation section, if it has one.
4861
4862 @item -u
4863 @itemx --unwind
4864 @cindex unwind information
4865 Displays the contents of the file's unwind section, if it has one. Only
4866 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4867 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
4868 support is not yet implemented for your architecture you could try
4869 dumping the contents of the @var{.eh_frames} section using the
4870 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
4871 options.
4872
4873 @item -d
4874 @itemx --dynamic
4875 @cindex ELF dynamic section information
4876 Displays the contents of the file's dynamic section, if it has one.
4877
4878 @item -V
4879 @itemx --version-info
4880 @cindex ELF version sections information
4881 Displays the contents of the version sections in the file, it they
4882 exist.
4883
4884 @item -A
4885 @itemx --arch-specific
4886 Displays architecture-specific information in the file, if there
4887 is any.
4888
4889 @item -D
4890 @itemx --use-dynamic
4891 When displaying symbols, this option makes @command{readelf} use the
4892 symbol hash tables in the file's dynamic section, rather than the
4893 symbol table sections.
4894
4895 When displaying relocations, this option makes @command{readelf}
4896 display the dynamic relocations rather than the static relocations.
4897
4898 @item -L
4899 @itemx --lint
4900 @itemx --enable-checks
4901 Displays warning messages about possible problems with the file(s)
4902 being examined. If used on its own then all of the contents of the
4903 file(s) will be examined. If used with one of the dumping options
4904 then the warning messages will only be produced for the things being
4905 displayed.
4906
4907 @item -x <number or name>
4908 @itemx --hex-dump=<number or name>
4909 Displays the contents of the indicated section as a hexadecimal bytes.
4910 A number identifies a particular section by index in the section table;
4911 any other string identifies all sections with that name in the object file.
4912
4913 @item -R <number or name>
4914 @itemx --relocated-dump=<number or name>
4915 Displays the contents of the indicated section as a hexadecimal
4916 bytes. A number identifies a particular section by index in the
4917 section table; any other string identifies all sections with that name
4918 in the object file. The contents of the section will be relocated
4919 before they are displayed.
4920
4921 @item -p <number or name>
4922 @itemx --string-dump=<number or name>
4923 Displays the contents of the indicated section as printable strings.
4924 A number identifies a particular section by index in the section table;
4925 any other string identifies all sections with that name in the object file.
4926
4927 @item -z
4928 @itemx --decompress
4929 Requests that the section(s) being dumped by @option{x}, @option{R} or
4930 @option{p} options are decompressed before being displayed. If the
4931 section(s) are not compressed then they are displayed as is.
4932
4933 @item -c
4934 @itemx --archive-index
4935 @cindex Archive file symbol index information
4936 Displays the file symbol index information contained in the header part
4937 of binary archives. Performs the same function as the @option{t}
4938 command to @command{ar}, but without using the BFD library. @xref{ar}.
4939
4940 @item -w[lLiaprmfFsOoRtUuTgAckK]
4941 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
4942 @include debug.options.texi
4943
4944 @include ctf.options.texi
4945 @item --ctf-symbols=@var{section}
4946 @item --ctf-strings=@var{section}
4947 Specify the name of another section from which the CTF file can inherit
4948 strings and symbols. By default, the @code{.symtab} and its linked
4949 string table are used.
4950
4951 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
4952 other must be specified as well.
4953
4954 @item -I
4955 @itemx --histogram
4956 Display a histogram of bucket list lengths when displaying the contents
4957 of the symbol tables.
4958
4959 @item -v
4960 @itemx --version
4961 Display the version number of readelf.
4962
4963 @item -W
4964 @itemx --wide
4965 Don't break output lines to fit into 80 columns. By default
4966 @command{readelf} breaks section header and segment listing lines for
4967 64-bit ELF files, so that they fit into 80 columns. This option causes
4968 @command{readelf} to print each section header resp. each segment one a
4969 single line, which is far more readable on terminals wider than 80 columns.
4970
4971 @item -T
4972 @itemx --silent-truncation
4973 Normally when readelf is displaying a symbol name, and it has to
4974 truncate the name to fit into an 80 column display, it will add a
4975 suffix of @code{[...]} to the name. This command line option
4976 disables this behaviour, allowing 5 more characters of the name to be
4977 displayed and restoring the old behaviour of readelf (prior to release
4978 2.35).
4979
4980 @item -H
4981 @itemx --help
4982 Display the command-line options understood by @command{readelf}.
4983
4984 @end table
4985
4986 @c man end
4987
4988 @ignore
4989 @c man begin SEEALSO readelf
4990 objdump(1), and the Info entries for @file{binutils}.
4991 @c man end
4992 @end ignore
4993
4994 @node elfedit
4995 @chapter elfedit
4996
4997 @cindex Update ELF header
4998 @kindex elfedit
4999
5000 @c man title elfedit update ELF header and program property of ELF files
5001
5002 @smallexample
5003 @c man begin SYNOPSIS elfedit
5004 elfedit [@option{--input-mach=}@var{machine}]
5005 [@option{--input-type=}@var{type}]
5006 [@option{--input-osabi=}@var{osabi}]
5007 @option{--output-mach=}@var{machine}
5008 @option{--output-type=}@var{type}
5009 @option{--output-osabi=}@var{osabi}
5010 @option{--enable-x86-feature=}@var{feature}
5011 @option{--disable-x86-feature=}@var{feature}
5012 [@option{-v}|@option{--version}]
5013 [@option{-h}|@option{--help}]
5014 @var{elffile}@dots{}
5015 @c man end
5016 @end smallexample
5017
5018 @c man begin DESCRIPTION elfedit
5019
5020 @command{elfedit} updates the ELF header and program property of ELF
5021 files which have the matching ELF machine and file types. The options
5022 control how and which fields in the ELF header and program property
5023 should be updated.
5024
5025 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
5026 64-bit ELF files are supported, as are archives containing ELF files.
5027 @c man end
5028
5029 @c man begin OPTIONS elfedit
5030
5031 The long and short forms of options, shown here as alternatives, are
5032 equivalent. At least one of the @option{--output-mach},
5033 @option{--output-type}, @option{--output-osabi},
5034 @option{--enable-x86-feature} and @option{--disable-x86-feature}
5035 options must be given.
5036
5037 @table @env
5038
5039 @item --input-mach=@var{machine}
5040 Set the matching input ELF machine type to @var{machine}. If
5041 @option{--input-mach} isn't specified, it will match any ELF
5042 machine types.
5043
5044 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5045 @var{K1OM} and @var{x86-64}.
5046
5047 @item --output-mach=@var{machine}
5048 Change the ELF machine type in the ELF header to @var{machine}. The
5049 supported ELF machine types are the same as @option{--input-mach}.
5050
5051 @item --input-type=@var{type}
5052 Set the matching input ELF file type to @var{type}. If
5053 @option{--input-type} isn't specified, it will match any ELF file types.
5054
5055 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5056
5057 @item --output-type=@var{type}
5058 Change the ELF file type in the ELF header to @var{type}. The
5059 supported ELF types are the same as @option{--input-type}.
5060
5061 @item --input-osabi=@var{osabi}
5062 Set the matching input ELF file OSABI to @var{osabi}. If
5063 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5064
5065 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5066 @var{GNU}, @var{Linux} (alias for @var{GNU}),
5067 @var{Solaris}, @var{AIX}, @var{Irix},
5068 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5069 @var{NSK}, @var{AROS} and @var{FenixOS}.
5070
5071 @item --output-osabi=@var{osabi}
5072 Change the ELF OSABI in the ELF header to @var{osabi}. The
5073 supported ELF OSABI are the same as @option{--input-osabi}.
5074
5075 @item --enable-x86-feature=@var{feature}
5076 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5077 ELF files with machine types of @var{i386} or @var{x86-64}. The
5078 supported features are, @var{ibt} and @var{shstk}.
5079
5080 @item --disable-x86-feature=@var{feature}
5081 Clear the @var{feature} bit in program property in @var{exec} or
5082 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5083 The supported features are the same as @option{--enable-x86-feature}.
5084
5085 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5086 are available only on hosts with @samp{mmap} support.
5087
5088 @item -v
5089 @itemx --version
5090 Display the version number of @command{elfedit}.
5091
5092 @item -h
5093 @itemx --help
5094 Display the command-line options understood by @command{elfedit}.
5095
5096 @end table
5097
5098 @c man end
5099
5100 @ignore
5101 @c man begin SEEALSO elfedit
5102 readelf(1), and the Info entries for @file{binutils}.
5103 @c man end
5104 @end ignore
5105
5106 @node Common Options
5107 @chapter Common Options
5108
5109 The following command-line options are supported by all of the
5110 programs described in this manual.
5111
5112 @c man begin OPTIONS
5113 @table @env
5114 @include at-file.texi
5115 @c man end
5116
5117 @item --help
5118 Display the command-line options supported by the program.
5119
5120 @item --version
5121 Display the version number of the program.
5122
5123 @c man begin OPTIONS
5124 @end table
5125 @c man end
5126
5127 @node Selecting the Target System
5128 @chapter Selecting the Target System
5129
5130 You can specify two aspects of the target system to the @sc{gnu}
5131 binary file utilities, each in several ways:
5132
5133 @itemize @bullet
5134 @item
5135 the target
5136
5137 @item
5138 the architecture
5139 @end itemize
5140
5141 In the following summaries, the lists of ways to specify values are in
5142 order of decreasing precedence. The ways listed first override those
5143 listed later.
5144
5145 The commands to list valid values only list the values for which the
5146 programs you are running were configured. If they were configured with
5147 @option{--enable-targets=all}, the commands list most of the available
5148 values, but a few are left out; not all targets can be configured in at
5149 once because some of them can only be configured @dfn{native} (on hosts
5150 with the same type as the target system).
5151
5152 @menu
5153 * Target Selection::
5154 * Architecture Selection::
5155 @end menu
5156
5157 @node Target Selection
5158 @section Target Selection
5159
5160 A @dfn{target} is an object file format. A given target may be
5161 supported for multiple architectures (@pxref{Architecture Selection}).
5162 A target selection may also have variations for different operating
5163 systems or architectures.
5164
5165 The command to list valid target values is @samp{objdump -i}
5166 (the first column of output contains the relevant information).
5167
5168 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5169 @samp{a.out-sunos-big}.
5170
5171 You can also specify a target using a configuration triplet. This is
5172 the same sort of name that is passed to @file{configure} to specify a
5173 target. When you use a configuration triplet as an argument, it must be
5174 fully canonicalized. You can see the canonical version of a triplet by
5175 running the shell script @file{config.sub} which is included with the
5176 sources.
5177
5178 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5179 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5180
5181 @subheading @command{objdump} Target
5182
5183 Ways to specify:
5184
5185 @enumerate
5186 @item
5187 command-line option: @option{-b} or @option{--target}
5188
5189 @item
5190 environment variable @code{GNUTARGET}
5191
5192 @item
5193 deduced from the input file
5194 @end enumerate
5195
5196 @subheading @command{objcopy} and @command{strip} Input Target
5197
5198 Ways to specify:
5199
5200 @enumerate
5201 @item
5202 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5203
5204 @item
5205 environment variable @code{GNUTARGET}
5206
5207 @item
5208 deduced from the input file
5209 @end enumerate
5210
5211 @subheading @command{objcopy} and @command{strip} Output Target
5212
5213 Ways to specify:
5214
5215 @enumerate
5216 @item
5217 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5218
5219 @item
5220 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5221
5222 @item
5223 environment variable @code{GNUTARGET}
5224
5225 @item
5226 deduced from the input file
5227 @end enumerate
5228
5229 @subheading @command{nm}, @command{size}, and @command{strings} Target
5230
5231 Ways to specify:
5232
5233 @enumerate
5234 @item
5235 command-line option: @option{--target}
5236
5237 @item
5238 environment variable @code{GNUTARGET}
5239
5240 @item
5241 deduced from the input file
5242 @end enumerate
5243
5244 @node Architecture Selection
5245 @section Architecture Selection
5246
5247 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5248 to run. Its name may contain a colon, separating the name of the
5249 processor family from the name of the particular @sc{cpu}.
5250
5251 The command to list valid architecture values is @samp{objdump -i} (the
5252 second column contains the relevant information).
5253
5254 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5255
5256 @subheading @command{objdump} Architecture
5257
5258 Ways to specify:
5259
5260 @enumerate
5261 @item
5262 command-line option: @option{-m} or @option{--architecture}
5263
5264 @item
5265 deduced from the input file
5266 @end enumerate
5267
5268 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5269
5270 Ways to specify:
5271
5272 @enumerate
5273 @item
5274 deduced from the input file
5275 @end enumerate
5276
5277 @node debuginfod
5278 @chapter debuginfod
5279 @cindex separate debug files
5280
5281 debuginfod is a web service that indexes ELF/DWARF debugging resources
5282 by build-id and serves them over HTTP.
5283
5284 Binutils can be built with the debuginfod client library
5285 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5286 This option is enabled by default if @code{libdebuginfod} is installed
5287 and found at configure time. This allows @command{objdump} and
5288 @command{readelf} to automatically query debuginfod servers for
5289 separate debug files when the files are otherwise not found.
5290
5291 debuginfod is packaged with elfutils, starting with version 0.178.
5292 You can get the latest version from `https://sourceware.org/elfutils/'.
5293
5294 @node Reporting Bugs
5295 @chapter Reporting Bugs
5296 @cindex bugs
5297 @cindex reporting bugs
5298
5299 Your bug reports play an essential role in making the binary utilities
5300 reliable.
5301
5302 Reporting a bug may help you by bringing a solution to your problem, or
5303 it may not. But in any case the principal function of a bug report is
5304 to help the entire community by making the next version of the binary
5305 utilities work better. Bug reports are your contribution to their
5306 maintenance.
5307
5308 In order for a bug report to serve its purpose, you must include the
5309 information that enables us to fix the bug.
5310
5311 @menu
5312 * Bug Criteria:: Have you found a bug?
5313 * Bug Reporting:: How to report bugs
5314 @end menu
5315
5316 @node Bug Criteria
5317 @section Have You Found a Bug?
5318 @cindex bug criteria
5319
5320 If you are not sure whether you have found a bug, here are some guidelines:
5321
5322 @itemize @bullet
5323 @cindex fatal signal
5324 @cindex crash
5325 @item
5326 If a binary utility gets a fatal signal, for any input whatever, that is
5327 a bug. Reliable utilities never crash.
5328
5329 @cindex error on valid input
5330 @item
5331 If a binary utility produces an error message for valid input, that is a
5332 bug.
5333
5334 @item
5335 If you are an experienced user of binary utilities, your suggestions for
5336 improvement are welcome in any case.
5337 @end itemize
5338
5339 @node Bug Reporting
5340 @section How to Report Bugs
5341 @cindex bug reports
5342 @cindex bugs, reporting
5343
5344 A number of companies and individuals offer support for @sc{gnu}
5345 products. If you obtained the binary utilities from a support
5346 organization, we recommend you contact that organization first.
5347
5348 You can find contact information for many support companies and
5349 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5350 distribution.
5351
5352 @ifset BUGURL
5353 In any event, we also recommend that you send bug reports for the binary
5354 utilities to @value{BUGURL}.
5355 @end ifset
5356
5357 The fundamental principle of reporting bugs usefully is this:
5358 @strong{report all the facts}. If you are not sure whether to state a
5359 fact or leave it out, state it!
5360
5361 Often people omit facts because they think they know what causes the
5362 problem and assume that some details do not matter. Thus, you might
5363 assume that the name of a file you use in an example does not matter.
5364 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5365 a stray memory reference which happens to fetch from the location where
5366 that pathname is stored in memory; perhaps, if the pathname were
5367 different, the contents of that location would fool the utility into
5368 doing the right thing despite the bug. Play it safe and give a
5369 specific, complete example. That is the easiest thing for you to do,
5370 and the most helpful.
5371
5372 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5373 it is new to us. Therefore, always write your bug reports on the assumption
5374 that the bug has not been reported previously.
5375
5376 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5377 bell?'' This cannot help us fix a bug, so it is basically useless. We
5378 respond by asking for enough details to enable us to investigate.
5379 You might as well expedite matters by sending them to begin with.
5380
5381 To enable us to fix the bug, you should include all these things:
5382
5383 @itemize @bullet
5384 @item
5385 The version of the utility. Each utility announces it if you start it
5386 with the @option{--version} argument.
5387
5388 Without this, we will not know whether there is any point in looking for
5389 the bug in the current version of the binary utilities.
5390
5391 @item
5392 Any patches you may have applied to the source, including any patches
5393 made to the @code{BFD} library.
5394
5395 @item
5396 The type of machine you are using, and the operating system name and
5397 version number.
5398
5399 @item
5400 What compiler (and its version) was used to compile the utilities---e.g.
5401 ``@code{gcc-2.7}''.
5402
5403 @item
5404 The command arguments you gave the utility to observe the bug. To
5405 guarantee you will not omit something important, list them all. A copy
5406 of the Makefile (or the output from make) is sufficient.
5407
5408 If we were to try to guess the arguments, we would probably guess wrong
5409 and then we might not encounter the bug.
5410
5411 @item
5412 A complete input file, or set of input files, that will reproduce the
5413 bug. If the utility is reading an object file or files, then it is
5414 generally most helpful to send the actual object files.
5415
5416 If the source files were produced exclusively using @sc{gnu} programs
5417 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5418 may be OK to send the source files rather than the object files. In
5419 this case, be sure to say exactly what version of @command{gcc}, or
5420 whatever, was used to produce the object files. Also say how
5421 @command{gcc}, or whatever, was configured.
5422
5423 @item
5424 A description of what behavior you observe that you believe is
5425 incorrect. For example, ``It gets a fatal signal.''
5426
5427 Of course, if the bug is that the utility gets a fatal signal, then we
5428 will certainly notice it. But if the bug is incorrect output, we might
5429 not notice unless it is glaringly wrong. You might as well not give us
5430 a chance to make a mistake.
5431
5432 Even if the problem you experience is a fatal signal, you should still
5433 say so explicitly. Suppose something strange is going on, such as your
5434 copy of the utility is out of sync, or you have encountered a bug in
5435 the C library on your system. (This has happened!) Your copy might
5436 crash and ours would not. If you told us to expect a crash, then when
5437 ours fails to crash, we would know that the bug was not happening for
5438 us. If you had not told us to expect a crash, then we would not be able
5439 to draw any conclusion from our observations.
5440
5441 @item
5442 If you wish to suggest changes to the source, send us context diffs, as
5443 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5444 option. Always send diffs from the old file to the new file. If you
5445 wish to discuss something in the @command{ld} source, refer to it by
5446 context, not by line number.
5447
5448 The line numbers in our development sources will not match those in your
5449 sources. Your line numbers would convey no useful information to us.
5450 @end itemize
5451
5452 Here are some things that are not necessary:
5453
5454 @itemize @bullet
5455 @item
5456 A description of the envelope of the bug.
5457
5458 Often people who encounter a bug spend a lot of time investigating
5459 which changes to the input file will make the bug go away and which
5460 changes will not affect it.
5461
5462 This is often time consuming and not very useful, because the way we
5463 will find the bug is by running a single example under the debugger
5464 with breakpoints, not by pure deduction from a series of examples.
5465 We recommend that you save your time for something else.
5466
5467 Of course, if you can find a simpler example to report @emph{instead}
5468 of the original one, that is a convenience for us. Errors in the
5469 output will be easier to spot, running under the debugger will take
5470 less time, and so on.
5471
5472 However, simplification is not vital; if you do not want to do this,
5473 report the bug anyway and send us the entire test case you used.
5474
5475 @item
5476 A patch for the bug.
5477
5478 A patch for the bug does help us if it is a good one. But do not omit
5479 the necessary information, such as the test case, on the assumption that
5480 a patch is all we need. We might see problems with your patch and decide
5481 to fix the problem another way, or we might not understand it at all.
5482
5483 Sometimes with programs as complicated as the binary utilities it is
5484 very hard to construct an example that will make the program follow a
5485 certain path through the code. If you do not send us the example, we
5486 will not be able to construct one, so we will not be able to verify that
5487 the bug is fixed.
5488
5489 And if we cannot understand what bug you are trying to fix, or why your
5490 patch should be an improvement, we will not install it. A test case will
5491 help us to understand.
5492
5493 @item
5494 A guess about what the bug is or what it depends on.
5495
5496 Such guesses are usually wrong. Even we cannot guess right about such
5497 things without first using the debugger to find the facts.
5498 @end itemize
5499
5500 @node GNU Free Documentation License
5501 @appendix GNU Free Documentation License
5502
5503 @include fdl.texi
5504
5505 @node Binutils Index
5506 @unnumbered Binutils Index
5507
5508 @printindex cp
5509
5510 @bye