]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blob - binutils/doc/binutils.texi
binutils: Add new GNU format mode to `size` utility
[thirdparty/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{} 1991-2019 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 * Reporting Bugs:: Reporting Bugs
158 * GNU Free Documentation License:: GNU Free Documentation License
159 * Binutils Index:: Binutils Index
160 @end menu
161
162 @node ar
163 @chapter ar
164
165 @kindex ar
166 @cindex archives
167 @cindex collections of files
168
169 @c man title ar create, modify, and extract from archives
170
171 @smallexample
172 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
173 ar -M [ <mri-script ]
174 @end smallexample
175
176 @c man begin DESCRIPTION ar
177
178 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
179 archives. An @dfn{archive} is a single file holding a collection of
180 other files in a structure that makes it possible to retrieve
181 the original individual files (called @dfn{members} of the archive).
182
183 The original files' contents, mode (permissions), timestamp, owner, and
184 group are preserved in the archive, and can be restored on
185 extraction.
186
187 @cindex name length
188 @sc{gnu} @command{ar} can maintain archives whose members have names of any
189 length; however, depending on how @command{ar} is configured on your
190 system, a limit on member-name length may be imposed for compatibility
191 with archive formats maintained with other tools. If it exists, the
192 limit is often 15 characters (typical of formats related to a.out) or 16
193 characters (typical of formats related to coff).
194
195 @cindex libraries
196 @command{ar} is considered a binary utility because archives of this sort
197 are most often used as @dfn{libraries} holding commonly needed
198 subroutines.
199
200 @cindex symbol index
201 @command{ar} creates an index to the symbols defined in relocatable
202 object modules in the archive when you specify the modifier @samp{s}.
203 Once created, this index is updated in the archive whenever @command{ar}
204 makes a change to its contents (save for the @samp{q} update operation).
205 An archive with such an index speeds up linking to the library, and
206 allows routines in the library to call each other without regard to
207 their placement in the archive.
208
209 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
210 table. If an archive lacks the table, another form of @command{ar} called
211 @command{ranlib} can be used to add just the table.
212
213 @cindex thin archives
214 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
215 which contains a symbol index and references to the original copies
216 of the member files of the archive. This is useful for building
217 libraries for use within a local build tree, where the relocatable
218 objects are expected to remain available, and copying the contents of
219 each object would only waste time and space.
220
221 An archive can either be @emph{thin} or it can be normal. It cannot
222 be both at the same time. Once an archive is created its format
223 cannot be changed without first deleting it and then creating a new
224 archive in its place.
225
226 Thin archives are also @emph{flattened}, so that adding one thin
227 archive to another thin archive does not nest it, as would happen with
228 a normal archive. Instead the elements of the first archive are added
229 individually to the second archive.
230
231 The paths to the elements of the archive are stored relative to the
232 archive itself.
233
234 @cindex compatibility, @command{ar}
235 @cindex @command{ar} compatibility
236 @sc{gnu} @command{ar} is designed to be compatible with two different
237 facilities. You can control its activity using command-line options,
238 like the different varieties of @command{ar} on Unix systems; or, if you
239 specify the single command-line option @option{-M}, you can control it
240 with a script supplied via standard input, like the MRI ``librarian''
241 program.
242
243 @c man end
244
245 @menu
246 * ar cmdline:: Controlling @command{ar} on the command line
247 * ar scripts:: Controlling @command{ar} with a script
248 @end menu
249
250 @page
251 @node ar cmdline
252 @section Controlling @command{ar} on the Command Line
253
254 @smallexample
255 @c man begin SYNOPSIS ar
256 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
257 @c man end
258 @end smallexample
259
260 @cindex Unix compatibility, @command{ar}
261 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
262 arguments to execute: one keyletter specifying the @emph{operation}
263 (optionally accompanied by other keyletters specifying
264 @emph{modifiers}), and the archive name to act on.
265
266 Most operations can also accept further @var{member} arguments,
267 specifying particular files to operate on.
268
269 @c man begin OPTIONS ar
270
271 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
272 flags @var{mod} in any order, within the first command-line argument.
273
274 If you wish, you may begin the first command-line argument with a
275 dash.
276
277 @cindex operations on archive
278 The @var{p} keyletter specifies what operation to execute; it may be
279 any of the following, but you must specify only one of them:
280
281 @table @samp
282 @item d
283 @cindex deleting from archive
284 @emph{Delete} modules from the archive. Specify the names of modules to
285 be deleted as @var{member}@dots{}; the archive is untouched if you
286 specify no files to delete.
287
288 If you specify the @samp{v} modifier, @command{ar} lists each module
289 as it is deleted.
290
291 @item m
292 @cindex moving in archive
293 Use this operation to @emph{move} members in an archive.
294
295 The ordering of members in an archive can make a difference in how
296 programs are linked using the library, if a symbol is defined in more
297 than one member.
298
299 If no modifiers are used with @code{m}, any members you name in the
300 @var{member} arguments are moved to the @emph{end} of the archive;
301 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
302 specified place instead.
303
304 @item p
305 @cindex printing from archive
306 @emph{Print} the specified members of the archive, to the standard
307 output file. If the @samp{v} modifier is specified, show the member
308 name before copying its contents to standard output.
309
310 If you specify no @var{member} arguments, all the files in the archive are
311 printed.
312
313 @item q
314 @cindex quick append to archive
315 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
316 @var{archive}, without checking for replacement.
317
318 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
319 operation; new members are always placed at the end of the archive.
320
321 The modifier @samp{v} makes @command{ar} list each file as it is appended.
322
323 Since the point of this operation is speed, implementations of
324 @command{ar} have the option of not updating the archive's symbol
325 table if one exists. Too many different systems however assume that
326 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
327 rebuild the table even with a quick append.
328
329 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
330 synonym for @samp{r} - replacing already existing files in the
331 archive and appending new ones at the end.
332
333 @item r
334 @cindex replacement in archive
335 Insert the files @var{member}@dots{} into @var{archive} (with
336 @emph{replacement}). This operation differs from @samp{q} in that any
337 previously existing members are deleted if their names match those being
338 added.
339
340 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
341 displays an error message, and leaves undisturbed any existing members
342 of the archive matching that name.
343
344 By default, new members are added at the end of the file; but you may
345 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
346 placement relative to some existing member.
347
348 The modifier @samp{v} used with this operation elicits a line of
349 output for each file inserted, along with one of the letters @samp{a} or
350 @samp{r} to indicate whether the file was appended (no old member
351 deleted) or replaced.
352
353 @item s
354 @cindex ranlib
355 Add an index to the archive, or update it if it already exists. Note
356 this command is an exception to the rule that there can only be one
357 command letter, as it is possible to use it as either a command or a
358 modifier. In either case it does the same thing.
359
360 @item t
361 @cindex contents of archive
362 Display a @emph{table} listing the contents of @var{archive}, or those
363 of the files listed in @var{member}@dots{} that are present in the
364 archive. Normally only the member name is shown, but if the modifier
365 @samp{O} is specified, then the corresponding offset of the member is also
366 displayed. Finally, in order to see the modes (permissions), timestamp,
367 owner, group, and size the @samp{v} modifier should be included.
368
369 If you do not specify a @var{member}, all files in the archive
370 are listed.
371
372 @cindex repeated names in archive
373 @cindex name duplication in archive
374 If there is more than one file with the same name (say, @samp{fie}) in
375 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
376 first instance; to see them all, you must ask for a complete
377 listing---in our example, @samp{ar t b.a}.
378 @c WRS only; per Gumby, this is implementation-dependent, and in a more
379 @c recent case in fact works the other way.
380
381 @item x
382 @cindex extract from archive
383 @emph{Extract} members (named @var{member}) from the archive. You can
384 use the @samp{v} modifier with this operation, to request that
385 @command{ar} list each name as it extracts it.
386
387 If you do not specify a @var{member}, all files in the archive
388 are extracted.
389
390 Files cannot be extracted from a thin archive.
391 @end table
392
393 A number of modifiers (@var{mod}) may immediately follow the @var{p}
394 keyletter, to specify variations on an operation's behavior:
395
396 @table @samp
397 @item a
398 @cindex relative placement in archive
399 Add new files @emph{after} an existing member of the
400 archive. If you use the modifier @samp{a}, the name of an existing archive
401 member must be present as the @var{relpos} argument, before the
402 @var{archive} specification.
403
404 @item b
405 Add new files @emph{before} an existing member of the
406 archive. If you use the modifier @samp{b}, the name of an existing archive
407 member must be present as the @var{relpos} argument, before the
408 @var{archive} specification. (same as @samp{i}).
409
410 @item c
411 @cindex creating archives
412 @emph{Create} the archive. The specified @var{archive} is always
413 created if it did not exist, when you request an update. But a warning is
414 issued unless you specify in advance that you expect to create it, by
415 using this modifier.
416
417 @item D
418 @cindex deterministic archives
419 @kindex --enable-deterministic-archives
420 Operate in @emph{deterministic} mode. When adding files and the archive
421 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
422 for all files. When this option is used, if @command{ar} is used with
423 identical options and identical input files, multiple runs will create
424 identical output files regardless of the input files' owners, groups,
425 file modes, or modification times.
426
427 If @file{binutils} was configured with
428 @option{--enable-deterministic-archives}, then this mode is on by default.
429 It can be disabled with the @samp{U} modifier, below.
430
431 @item f
432 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
433 names of any length. This will cause it to create archives which are
434 not compatible with the native @command{ar} program on some systems. If
435 this is a concern, the @samp{f} modifier may be used to truncate file
436 names when putting them in the archive.
437
438 @item i
439 Insert new files @emph{before} an existing member of the
440 archive. If you use the modifier @samp{i}, the name of an existing archive
441 member must be present as the @var{relpos} argument, before the
442 @var{archive} specification. (same as @samp{b}).
443
444 @item l
445 This modifier is accepted but not used.
446 @c whaffor ar l modifier??? presumably compat; with
447 @c what???---doc@@cygnus.com, 25jan91
448
449 @item N
450 Uses the @var{count} parameter. This is used if there are multiple
451 entries in the archive with the same name. Extract or delete instance
452 @var{count} of the given name from the archive.
453
454 @item o
455 @cindex dates in archive
456 Preserve the @emph{original} dates of members when extracting them. If
457 you do not specify this modifier, files extracted from the archive
458 are stamped with the time of extraction.
459
460 @item O
461 @cindex offsets of files
462 Display member offsets inside the archive. Use together with the @samp{t}
463 option.
464
465 @item P
466 Use the full path name when matching names in the archive. @sc{gnu}
467 @command{ar} can not create an archive with a full path name (such archives
468 are not POSIX complaint), but other archive creators can. This option
469 will cause @sc{gnu} @command{ar} to match file names using a complete path
470 name, which can be convenient when extracting a single file from an
471 archive created by another tool.
472
473 @item s
474 @cindex writing archive index
475 Write an object-file index into the archive, or update an existing one,
476 even if no other change is made to the archive. You may use this modifier
477 flag either with any operation, or alone. Running @samp{ar s} on an
478 archive is equivalent to running @samp{ranlib} on it.
479
480 @item S
481 @cindex not writing archive index
482 Do not generate an archive symbol table. This can speed up building a
483 large library in several steps. The resulting archive can not be used
484 with the linker. In order to build a symbol table, you must omit the
485 @samp{S} modifier on the last execution of @samp{ar}, or you must run
486 @samp{ranlib} on the archive.
487
488 @item T
489 @cindex creating thin archive
490 Make the specified @var{archive} a @emph{thin} archive. If it already
491 exists and is a regular archive, the existing members must be present
492 in the same directory as @var{archive}.
493
494 @item u
495 @cindex updating an archive
496 Normally, @samp{ar r}@dots{} inserts all files
497 listed into the archive. If you would like to insert @emph{only} those
498 of the files you list that are newer than existing members of the same
499 names, use this modifier. The @samp{u} modifier is allowed only for the
500 operation @samp{r} (replace). In particular, the combination @samp{qu} is
501 not allowed, since checking the timestamps would lose any speed
502 advantage from the operation @samp{q}.
503
504 @item U
505 @cindex deterministic archives
506 @kindex --enable-deterministic-archives
507 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
508 of the @samp{D} modifier, above: added files and the archive index will
509 get their actual UID, GID, timestamp, and file mode values.
510
511 This is the default unless @file{binutils} was configured with
512 @option{--enable-deterministic-archives}.
513
514 @item v
515 This modifier requests the @emph{verbose} version of an operation. Many
516 operations display additional information, such as filenames processed,
517 when the modifier @samp{v} is appended.
518
519 @item V
520 This modifier shows the version number of @command{ar}.
521 @end table
522
523 The @command{ar} program also supports some command-line options which
524 are neither modifiers nor actions, but which do change its behaviour
525 in specific ways:
526
527 @table @samp
528 @item --help
529 Displays the list of command-line options supported by @command{ar}
530 and then exits.
531
532 @item --version
533 Displays the version information of @command{ar} and then exits.
534
535 @item -X32_64
536 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
537 compatibility with AIX. The behaviour produced by this option is the
538 default for @sc{gnu} @command{ar}. @command{ar} does not support any
539 of the other @samp{-X} options; in particular, it does not support
540 @option{-X32} which is the default for AIX @command{ar}.
541
542 @item --plugin @var{name}
543 @cindex plugins
544 The optional command-line switch @option{--plugin @var{name}} causes
545 @command{ar} to load the plugin called @var{name} which adds support
546 for more file formats, including object files with link-time
547 optimization information.
548
549 This option is only available if the toolchain has been built with
550 plugin support enabled.
551
552 If @option{--plugin} is not provided, but plugin support has been
553 enabled then @command{ar} iterates over the files in
554 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
555 plugin that claims the object in question is used.
556
557 Please note that this plugin search directory is @emph{not} the one
558 used by @command{ld}'s @option{-plugin} option. In order to make
559 @command{ar} use the linker plugin it must be copied into the
560 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
561 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
562 based compilations it is called @file{LLVMgold.so}. The GCC plugin
563 is always backwards compatible with earlier versions, so it is
564 sufficient to just copy the newest one.
565
566 @item --target @var{target}
567 The optional command-line switch @option{--target @var{bfdname}}
568 specifies that the archive members are in an object code format
569 different from your system's default format. See
570 @xref{Target Selection}, for more information.
571 @end table
572 @c man end
573
574 @ignore
575 @c man begin SEEALSO ar
576 nm(1), ranlib(1), and the Info entries for @file{binutils}.
577 @c man end
578 @end ignore
579
580 @node ar scripts
581 @section Controlling @command{ar} with a Script
582
583 @smallexample
584 ar -M [ <@var{script} ]
585 @end smallexample
586
587 @cindex MRI compatibility, @command{ar}
588 @cindex scripts, @command{ar}
589 If you use the single command-line option @samp{-M} with @command{ar}, you
590 can control its operation with a rudimentary command language. This
591 form of @command{ar} operates interactively if standard input is coming
592 directly from a terminal. During interactive use, @command{ar} prompts for
593 input (the prompt is @samp{AR >}), and continues executing even after
594 errors. If you redirect standard input to a script file, no prompts are
595 issued, and @command{ar} abandons execution (with a nonzero exit code)
596 on any error.
597
598 The @command{ar} command language is @emph{not} designed to be equivalent
599 to the command-line options; in fact, it provides somewhat less control
600 over archives. The only purpose of the command language is to ease the
601 transition to @sc{gnu} @command{ar} for developers who already have scripts
602 written for the MRI ``librarian'' program.
603
604 The syntax for the @command{ar} command language is straightforward:
605 @itemize @bullet
606 @item
607 commands are recognized in upper or lower case; for example, @code{LIST}
608 is the same as @code{list}. In the following descriptions, commands are
609 shown in upper case for clarity.
610
611 @item
612 a single command may appear on each line; it is the first word on the
613 line.
614
615 @item
616 empty lines are allowed, and have no effect.
617
618 @item
619 comments are allowed; text after either of the characters @samp{*}
620 or @samp{;} is ignored.
621
622 @item
623 Whenever you use a list of names as part of the argument to an @command{ar}
624 command, you can separate the individual names with either commas or
625 blanks. Commas are shown in the explanations below, for clarity.
626
627 @item
628 @samp{+} is used as a line continuation character; if @samp{+} appears
629 at the end of a line, the text on the following line is considered part
630 of the current command.
631 @end itemize
632
633 Here are the commands you can use in @command{ar} scripts, or when using
634 @command{ar} interactively. Three of them have special significance:
635
636 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
637 a temporary file required for most of the other commands.
638
639 @code{SAVE} commits the changes so far specified by the script. Prior
640 to @code{SAVE}, commands affect only the temporary copy of the current
641 archive.
642
643 @table @code
644 @item ADDLIB @var{archive}
645 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
646 Add all the contents of @var{archive} (or, if specified, each named
647 @var{module} from @var{archive}) to the current archive.
648
649 Requires prior use of @code{OPEN} or @code{CREATE}.
650
651 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
652 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
653 @c else like "ar q..."
654 Add each named @var{member} as a module in the current archive.
655
656 Requires prior use of @code{OPEN} or @code{CREATE}.
657
658 @item CLEAR
659 Discard the contents of the current archive, canceling the effect of
660 any operations since the last @code{SAVE}. May be executed (with no
661 effect) even if no current archive is specified.
662
663 @item CREATE @var{archive}
664 Creates an archive, and makes it the current archive (required for many
665 other commands). The new archive is created with a temporary name; it
666 is not actually saved as @var{archive} until you use @code{SAVE}.
667 You can overwrite existing archives; similarly, the contents of any
668 existing file named @var{archive} will not be destroyed until @code{SAVE}.
669
670 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
671 Delete each listed @var{module} from the current archive; equivalent to
672 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
673
674 Requires prior use of @code{OPEN} or @code{CREATE}.
675
676 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
677 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
678 List each named @var{module} present in @var{archive}. The separate
679 command @code{VERBOSE} specifies the form of the output: when verbose
680 output is off, output is like that of @samp{ar -t @var{archive}
681 @var{module}@dots{}}. When verbose output is on, the listing is like
682 @samp{ar -tv @var{archive} @var{module}@dots{}}.
683
684 Output normally goes to the standard output stream; however, if you
685 specify @var{outputfile} as a final argument, @command{ar} directs the
686 output to that file.
687
688 @item END
689 Exit from @command{ar}, with a @code{0} exit code to indicate successful
690 completion. This command does not save the output file; if you have
691 changed the current archive since the last @code{SAVE} command, those
692 changes are lost.
693
694 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
695 Extract each named @var{module} from the current archive, writing them
696 into the current directory as separate files. Equivalent to @samp{ar -x
697 @var{archive} @var{module}@dots{}}.
698
699 Requires prior use of @code{OPEN} or @code{CREATE}.
700
701 @ignore
702 @c FIXME Tokens but no commands???
703 @item FULLDIR
704
705 @item HELP
706 @end ignore
707
708 @item LIST
709 Display full contents of the current archive, in ``verbose'' style
710 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
711 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
712 enhancement, rather than present for MRI compatibility.)
713
714 Requires prior use of @code{OPEN} or @code{CREATE}.
715
716 @item OPEN @var{archive}
717 Opens an existing archive for use as the current archive (required for
718 many other commands). Any changes as the result of subsequent commands
719 will not actually affect @var{archive} until you next use @code{SAVE}.
720
721 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
722 In the current archive, replace each existing @var{module} (named in
723 the @code{REPLACE} arguments) from files in the current working directory.
724 To execute this command without errors, both the file, and the module in
725 the current archive, must exist.
726
727 Requires prior use of @code{OPEN} or @code{CREATE}.
728
729 @item VERBOSE
730 Toggle an internal flag governing the output from @code{DIRECTORY}.
731 When the flag is on, @code{DIRECTORY} output matches output from
732 @samp{ar -tv }@dots{}.
733
734 @item SAVE
735 Commit your changes to the current archive, and actually save it as a
736 file with the name specified in the last @code{CREATE} or @code{OPEN}
737 command.
738
739 Requires prior use of @code{OPEN} or @code{CREATE}.
740
741 @end table
742
743 @iftex
744 @node ld
745 @chapter ld
746 @cindex linker
747 @kindex ld
748 The @sc{gnu} linker @command{ld} is now described in a separate manual.
749 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
750 @end iftex
751
752 @node nm
753 @chapter nm
754 @cindex symbols
755 @kindex nm
756
757 @c man title nm list symbols from object files
758
759 @smallexample
760 @c man begin SYNOPSIS nm
761 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
762 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
763 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
764 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
765 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
766 [@option{-n}|@option{-v}|@option{--numeric-sort}]
767 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
768 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
769 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
770 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
771 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
772 [@option{--plugin} @var{name}]
773 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
774 [@option{--size-sort}] [@option{--special-syms}]
775 [@option{--synthetic}] [@option{--with-symbol-versions}] [@option{--target=}@var{bfdname}]
776 [@var{objfile}@dots{}]
777 @c man end
778 @end smallexample
779
780 @c man begin DESCRIPTION nm
781 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
782 If no object files are listed as arguments, @command{nm} assumes the file
783 @file{a.out}.
784
785 For each symbol, @command{nm} shows:
786
787 @itemize @bullet
788 @item
789 The symbol value, in the radix selected by options (see below), or
790 hexadecimal by default.
791
792 @item
793 The symbol type. At least the following types are used; others are, as
794 well, depending on the object file format. If lowercase, the symbol is
795 usually local; if uppercase, the symbol is global (external). There
796 are however a few lowercase symbols that are shown for special global
797 symbols (@code{u}, @code{v} and @code{w}).
798
799 @c Some more detail on exactly what these symbol types are used for
800 @c would be nice.
801 @table @code
802 @item A
803 The symbol's value is absolute, and will not be changed by further
804 linking.
805
806 @item B
807 @itemx b
808 The symbol is in the BSS data section. This section typically
809 contains zero-initialized or uninitialized data, although the exact
810 behavior is system dependent.
811
812 @item C
813 The symbol is common. Common symbols are uninitialized data. When
814 linking, multiple common symbols may appear with the same name. If the
815 symbol is defined anywhere, the common symbols are treated as undefined
816 references.
817 @ifclear man
818 For more details on common symbols, see the discussion of
819 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
820 @end ifclear
821
822 @item D
823 @itemx d
824 The symbol is in the initialized data section.
825
826 @item G
827 @itemx g
828 The symbol is in an initialized data section for small objects. Some
829 object file formats permit more efficient access to small data objects,
830 such as a global int variable as opposed to a large global array.
831
832 @item i
833 For PE format files this indicates that the symbol is in a section
834 specific to the implementation of DLLs. For ELF format files this
835 indicates that the symbol is an indirect function. This is a GNU
836 extension to the standard set of ELF symbol types. It indicates a
837 symbol which if referenced by a relocation does not evaluate to its
838 address, but instead must be invoked at runtime. The runtime
839 execution will then return the value to be used in the relocation.
840
841 @item I
842 The symbol is an indirect reference to another symbol.
843
844 @item N
845 The symbol is a debugging symbol.
846
847 @item p
848 The symbols is in a stack unwind section.
849
850 @item R
851 @itemx r
852 The symbol is in a read only data section.
853
854 @item S
855 @itemx s
856 The symbol is in an uninitialized or zero-initialized data section
857 for small objects.
858
859 @item T
860 @itemx t
861 The symbol is in the text (code) section.
862
863 @item U
864 The symbol is undefined.
865
866 @item u
867 The symbol is a unique global symbol. This is a GNU extension to the
868 standard set of ELF symbol bindings. For such a symbol the dynamic linker
869 will make sure that in the entire process there is just one symbol with
870 this name and type in use.
871
872 @item V
873 @itemx v
874 The symbol is a weak object. When a weak defined symbol is linked with
875 a normal defined symbol, the normal defined symbol is used with no error.
876 When a weak undefined symbol is linked and the symbol is not defined,
877 the value of the weak symbol becomes zero with no error. On some
878 systems, uppercase indicates that a default value has been specified.
879
880 @item W
881 @itemx w
882 The symbol is a weak symbol that has not been specifically tagged as a
883 weak object symbol. When a weak defined symbol is linked with a normal
884 defined symbol, the normal defined symbol is used with no error.
885 When a weak undefined symbol is linked and the symbol is not defined,
886 the value of the symbol is determined in a system-specific manner without
887 error. On some systems, uppercase indicates that a default value has been
888 specified.
889
890 @item -
891 The symbol is a stabs symbol in an a.out object file. In this case, the
892 next values printed are the stabs other field, the stabs desc field, and
893 the stab type. Stabs symbols are used to hold debugging information.
894
895 @item ?
896 The symbol type is unknown, or object file format specific.
897 @end table
898
899 @item
900 The symbol name.
901 @end itemize
902
903 @c man end
904
905 @c man begin OPTIONS nm
906 The long and short forms of options, shown here as alternatives, are
907 equivalent.
908
909 @table @env
910 @item -A
911 @itemx -o
912 @itemx --print-file-name
913 @cindex input file name
914 @cindex file name
915 @cindex source file name
916 Precede each symbol by the name of the input file (or archive member)
917 in which it was found, rather than identifying the input file once only,
918 before all of its symbols.
919
920 @item -a
921 @itemx --debug-syms
922 @cindex debugging symbols
923 Display all symbols, even debugger-only symbols; normally these are not
924 listed.
925
926 @item -B
927 @cindex @command{nm} format
928 @cindex @command{nm} compatibility
929 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
930
931 @item -C
932 @itemx --demangle[=@var{style}]
933 @cindex demangling in nm
934 Decode (@dfn{demangle}) low-level symbol names into user-level names.
935 Besides removing any initial underscore prepended by the system, this
936 makes C++ function names readable. Different compilers have different
937 mangling styles. The optional demangling style argument can be used to
938 choose an appropriate demangling style for your compiler. @xref{c++filt},
939 for more information on demangling.
940
941 @item --no-demangle
942 Do not demangle low-level symbol names. This is the default.
943
944 @item --recurse-limit
945 @itemx --no-recurse-limit
946 @itemx --recursion-limit
947 @itemx --no-recursion-limit
948 Enables or disables a limit on the amount of recursion performed
949 whilst demangling strings. Since the name mangling formats allow for
950 an inifinite level of recursion it is possible to create strings whose
951 decoding will exhaust the amount of stack space available on the host
952 machine, triggering a memory fault. The limit tries to prevent this
953 from happening by restricting recursion to 2048 levels of nesting.
954
955 The default is for this limit to be enabled, but disabling it may be
956 necessary in order to demangle truly complicated names. Note however
957 that if the recursion limit is disabled then stack exhaustion is
958 possible and any bug reports about such an event will be rejected.
959
960 @item -D
961 @itemx --dynamic
962 @cindex dynamic symbols
963 Display the dynamic symbols rather than the normal symbols. This is
964 only meaningful for dynamic objects, such as certain types of shared
965 libraries.
966
967 @item -f @var{format}
968 @itemx --format=@var{format}
969 @cindex @command{nm} format
970 @cindex @command{nm} compatibility
971 Use the output format @var{format}, which can be @code{bsd},
972 @code{sysv}, or @code{posix}. The default is @code{bsd}.
973 Only the first character of @var{format} is significant; it can be
974 either upper or lower case.
975
976 @item -g
977 @itemx --extern-only
978 @cindex external symbols
979 Display only external symbols.
980
981 @item -h
982 @itemx --help
983 Show a summary of the options to @command{nm} and exit.
984
985 @item -l
986 @itemx --line-numbers
987 @cindex symbol line numbers
988 For each symbol, use debugging information to try to find a filename and
989 line number. For a defined symbol, look for the line number of the
990 address of the symbol. For an undefined symbol, look for the line
991 number of a relocation entry which refers to the symbol. If line number
992 information can be found, print it after the other symbol information.
993
994 @item --inlines
995 @cindex objdump inlines
996 When option @option{-l} is active, if the address belongs to a
997 function that was inlined, then this option causes the source
998 information for all enclosing scopes back to the first non-inlined
999 function to be printed as well. For example, if @code{main} inlines
1000 @code{callee1} which inlines @code{callee2}, and address is from
1001 @code{callee2}, the source information for @code{callee1} and @code{main}
1002 will also be printed.
1003
1004 @item -n
1005 @itemx -v
1006 @itemx --numeric-sort
1007 Sort symbols numerically by their addresses, rather than alphabetically
1008 by their names.
1009
1010 @item -p
1011 @itemx --no-sort
1012 @cindex sorting symbols
1013 Do not bother to sort the symbols in any order; print them in the order
1014 encountered.
1015
1016 @item -P
1017 @itemx --portability
1018 Use the POSIX.2 standard output format instead of the default format.
1019 Equivalent to @samp{-f posix}.
1020
1021 @item -r
1022 @itemx --reverse-sort
1023 Reverse the order of the sort (whether numeric or alphabetic); let the
1024 last come first.
1025
1026 @item -S
1027 @itemx --print-size
1028 Print both value and size of defined symbols for the @code{bsd} output style.
1029 This option has no effect for object formats that do not record symbol
1030 sizes, unless @samp{--size-sort} is also used in which case a
1031 calculated size is displayed.
1032
1033 @item -s
1034 @itemx --print-armap
1035 @cindex symbol index, listing
1036 When listing symbols from archive members, include the index: a mapping
1037 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1038 contain definitions for which names.
1039
1040 @item -t @var{radix}
1041 @itemx --radix=@var{radix}
1042 Use @var{radix} as the radix for printing the symbol values. It must be
1043 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1044
1045 @item -u
1046 @itemx --undefined-only
1047 @cindex external symbols
1048 @cindex undefined symbols
1049 Display only undefined symbols (those external to each object file).
1050
1051 @item -V
1052 @itemx --version
1053 Show the version number of @command{nm} and exit.
1054
1055 @item -X
1056 This option is ignored for compatibility with the AIX version of
1057 @command{nm}. It takes one parameter which must be the string
1058 @option{32_64}. The default mode of AIX @command{nm} corresponds
1059 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1060
1061 @item --defined-only
1062 @cindex external symbols
1063 @cindex undefined symbols
1064 Display only defined symbols for each object file.
1065
1066 @item --plugin @var{name}
1067 @cindex plugins
1068 Load the plugin called @var{name} to add support for extra target
1069 types. This option is only available if the toolchain has been built
1070 with plugin support enabled.
1071
1072 If @option{--plugin} is not provided, but plugin support has been
1073 enabled then @command{nm} iterates over the files in
1074 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1075 plugin that claims the object in question is used.
1076
1077 Please note that this plugin search directory is @emph{not} the one
1078 used by @command{ld}'s @option{-plugin} option. In order to make
1079 @command{nm} use the linker plugin it must be copied into the
1080 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1081 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1082 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1083 is always backwards compatible with earlier versions, so it is
1084 sufficient to just copy the newest one.
1085
1086 @item --size-sort
1087 Sort symbols by size. For ELF objects symbol sizes are read from the
1088 ELF, for other object types the symbol sizes are computed as the
1089 difference between the value of the symbol and the value of the symbol
1090 with the next higher value. If the @code{bsd} output format is used
1091 the size of the symbol is printed, rather than the value, and
1092 @samp{-S} must be used in order both size and value to be printed.
1093
1094 @item --special-syms
1095 Display symbols which have a target-specific special meaning. These
1096 symbols are usually used by the target for some special processing and
1097 are not normally helpful when included in the normal symbol lists.
1098 For example for ARM targets this option would skip the mapping symbols
1099 used to mark transitions between ARM code, THUMB code and data.
1100
1101 @item --synthetic
1102 Include synthetic symbols in the output. These are special symbols
1103 created by the linker for various purposes. They are not shown by
1104 default since they are not part of the binary's original source code.
1105
1106 @item --with-symbol-versions
1107 Enables the display of symbol version information if any exists. The
1108 version string is displayed as a suffix to the symbol name, preceeded by
1109 an @@ character. For example @samp{foo@@VER_1}. If the version is
1110 the default version to be used when resolving unversioned references
1111 to the symbol then it is displayed as a suffix preceeded by two @@
1112 characters. For example @samp{foo@@@@VER_2}.
1113
1114 @item --target=@var{bfdname}
1115 @cindex object code format
1116 Specify an object code format other than your system's default format.
1117 @xref{Target Selection}, for more information.
1118
1119 @end table
1120
1121 @c man end
1122
1123 @ignore
1124 @c man begin SEEALSO nm
1125 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1126 @c man end
1127 @end ignore
1128
1129 @node objcopy
1130 @chapter objcopy
1131
1132 @c man title objcopy copy and translate object files
1133
1134 @smallexample
1135 @c man begin SYNOPSIS objcopy
1136 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1137 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1138 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1139 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1140 [@option{-S}|@option{--strip-all}]
1141 [@option{-g}|@option{--strip-debug}]
1142 [@option{--strip-unneeded}]
1143 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1144 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1145 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1146 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1147 [@option{--localize-hidden}]
1148 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1149 [@option{--globalize-symbol=}@var{symbolname}]
1150 [@option{--globalize-symbols=}@var{filename}]
1151 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1152 [@option{-w}|@option{--wildcard}]
1153 [@option{-x}|@option{--discard-all}]
1154 [@option{-X}|@option{--discard-locals}]
1155 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1156 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1157 [@option{--interleave-width=}@var{width}]
1158 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1159 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1160 [@option{--remove-relocations=}@var{sectionpattern}]
1161 [@option{-p}|@option{--preserve-dates}]
1162 [@option{-D}|@option{--enable-deterministic-archives}]
1163 [@option{-U}|@option{--disable-deterministic-archives}]
1164 [@option{--debugging}]
1165 [@option{--gap-fill=}@var{val}]
1166 [@option{--pad-to=}@var{address}]
1167 [@option{--set-start=}@var{val}]
1168 [@option{--adjust-start=}@var{incr}]
1169 [@option{--change-addresses=}@var{incr}]
1170 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1171 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1172 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1173 [@option{--change-warnings}] [@option{--no-change-warnings}]
1174 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1175 [@option{--add-section} @var{sectionname}=@var{filename}]
1176 [@option{--dump-section} @var{sectionname}=@var{filename}]
1177 [@option{--update-section} @var{sectionname}=@var{filename}]
1178 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1179 [@option{--long-section-names} @{enable,disable,keep@}]
1180 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1181 [@option{--reverse-bytes=}@var{num}]
1182 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1183 [@option{--redefine-sym} @var{old}=@var{new}]
1184 [@option{--redefine-syms=}@var{filename}]
1185 [@option{--weaken}]
1186 [@option{--keep-symbols=}@var{filename}]
1187 [@option{--strip-symbols=}@var{filename}]
1188 [@option{--strip-unneeded-symbols=}@var{filename}]
1189 [@option{--keep-global-symbols=}@var{filename}]
1190 [@option{--localize-symbols=}@var{filename}]
1191 [@option{--weaken-symbols=}@var{filename}]
1192 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1193 [@option{--alt-machine-code=}@var{index}]
1194 [@option{--prefix-symbols=}@var{string}]
1195 [@option{--prefix-sections=}@var{string}]
1196 [@option{--prefix-alloc-sections=}@var{string}]
1197 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1198 [@option{--keep-file-symbols}]
1199 [@option{--only-keep-debug}]
1200 [@option{--strip-dwo}]
1201 [@option{--extract-dwo}]
1202 [@option{--extract-symbol}]
1203 [@option{--writable-text}]
1204 [@option{--readonly-text}]
1205 [@option{--pure}]
1206 [@option{--impure}]
1207 [@option{--file-alignment=}@var{num}]
1208 [@option{--heap=}@var{size}]
1209 [@option{--image-base=}@var{address}]
1210 [@option{--section-alignment=}@var{num}]
1211 [@option{--stack=}@var{size}]
1212 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1213 [@option{--compress-debug-sections}]
1214 [@option{--decompress-debug-sections}]
1215 [@option{--elf-stt-common=@var{val}}]
1216 [@option{--merge-notes}]
1217 [@option{--no-merge-notes}]
1218 [@option{-v}|@option{--verbose}]
1219 [@option{-V}|@option{--version}]
1220 [@option{--help}] [@option{--info}]
1221 @var{infile} [@var{outfile}]
1222 @c man end
1223 @end smallexample
1224
1225 @c man begin DESCRIPTION objcopy
1226 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1227 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1228 read and write the object files. It can write the destination object
1229 file in a format different from that of the source object file. The
1230 exact behavior of @command{objcopy} is controlled by command-line options.
1231 Note that @command{objcopy} should be able to copy a fully linked file
1232 between any two formats. However, copying a relocatable object file
1233 between any two formats may not work as expected.
1234
1235 @command{objcopy} creates temporary files to do its translations and
1236 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1237 translation work; it has access to all the formats described in @sc{bfd}
1238 and thus is able to recognize most formats without being told
1239 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1240
1241 @command{objcopy} can be used to generate S-records by using an output
1242 target of @samp{srec} (e.g., use @samp{-O srec}).
1243
1244 @command{objcopy} can be used to generate a raw binary file by using an
1245 output target of @samp{binary} (e.g., use @option{-O binary}). When
1246 @command{objcopy} generates a raw binary file, it will essentially produce
1247 a memory dump of the contents of the input object file. All symbols and
1248 relocation information will be discarded. The memory dump will start at
1249 the load address of the lowest section copied into the output file.
1250
1251 When generating an S-record or a raw binary file, it may be helpful to
1252 use @option{-S} to remove sections containing debugging information. In
1253 some cases @option{-R} will be useful to remove sections which contain
1254 information that is not needed by the binary file.
1255
1256 Note---@command{objcopy} is not able to change the endianness of its input
1257 files. If the input format has an endianness (some formats do not),
1258 @command{objcopy} can only copy the inputs into file formats that have the
1259 same endianness or which have no endianness (e.g., @samp{srec}).
1260 (However, see the @option{--reverse-bytes} option.)
1261
1262 @c man end
1263
1264 @c man begin OPTIONS objcopy
1265
1266 @table @env
1267 @item @var{infile}
1268 @itemx @var{outfile}
1269 The input and output files, respectively.
1270 If you do not specify @var{outfile}, @command{objcopy} creates a
1271 temporary file and destructively renames the result with
1272 the name of @var{infile}.
1273
1274 @item -I @var{bfdname}
1275 @itemx --input-target=@var{bfdname}
1276 Consider the source file's object format to be @var{bfdname}, rather than
1277 attempting to deduce it. @xref{Target Selection}, for more information.
1278
1279 @item -O @var{bfdname}
1280 @itemx --output-target=@var{bfdname}
1281 Write the output file using the object format @var{bfdname}.
1282 @xref{Target Selection}, for more information.
1283
1284 @item -F @var{bfdname}
1285 @itemx --target=@var{bfdname}
1286 Use @var{bfdname} as the object format for both the input and the output
1287 file; i.e., simply transfer data from source to destination with no
1288 translation. @xref{Target Selection}, for more information.
1289
1290 @item -B @var{bfdarch}
1291 @itemx --binary-architecture=@var{bfdarch}
1292 Useful when transforming a architecture-less input file into an object file.
1293 In this case the output architecture can be set to @var{bfdarch}. This
1294 option will be ignored if the input file has a known @var{bfdarch}. You
1295 can access this binary data inside a program by referencing the special
1296 symbols that are created by the conversion process. These symbols are
1297 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1298 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1299 an object file and then access it in your code using these symbols.
1300
1301 @item -j @var{sectionpattern}
1302 @itemx --only-section=@var{sectionpattern}
1303 Copy only the indicated sections from the input file to the output file.
1304 This option may be given more than once. Note that using this option
1305 inappropriately may make the output file unusable. Wildcard
1306 characters are accepted in @var{sectionpattern}.
1307
1308 If the first character of @var{sectionpattern} is the exclamation
1309 point (!) then matching sections will not be copied, even if earlier
1310 use of @option{--only-section} on the same command line would
1311 otherwise copy it. For example:
1312
1313 @smallexample
1314 --only-section=.text.* --only-section=!.text.foo
1315 @end smallexample
1316
1317 will copy all sectinos maching '.text.*' but not the section
1318 '.text.foo'.
1319
1320 @item -R @var{sectionpattern}
1321 @itemx --remove-section=@var{sectionpattern}
1322 Remove any section matching @var{sectionpattern} from the output file.
1323 This option may be given more than once. Note that using this option
1324 inappropriately may make the output file unusable. Wildcard
1325 characters are accepted in @var{sectionpattern}. Using both the
1326 @option{-j} and @option{-R} options together results in undefined
1327 behaviour.
1328
1329 If the first character of @var{sectionpattern} is the exclamation
1330 point (!) then matching sections will not be removed even if an
1331 earlier use of @option{--remove-section} on the same command line
1332 would otherwise remove it. For example:
1333
1334 @smallexample
1335 --remove-section=.text.* --remove-section=!.text.foo
1336 @end smallexample
1337
1338 will remove all sections matching the pattern '.text.*', but will not
1339 remove the section '.text.foo'.
1340
1341 @item --remove-relocations=@var{sectionpattern}
1342 Remove non-dynamic relocations from the output file for any section
1343 matching @var{sectionpattern}. This option may be given more than
1344 once. Note that using this option inappropriately may make the output
1345 file unusable, and attempting to remove a dynamic relocation section
1346 such as @samp{.rela.plt} from an executable or shared library with
1347 @option{--remove-relocations=.plt} will not work. Wildcard characters
1348 are accepted in @var{sectionpattern}.
1349 For example:
1350
1351 @smallexample
1352 --remove-relocations=.text.*
1353 @end smallexample
1354
1355 will remove the relocations for all sections matching the pattern
1356 '.text.*'.
1357
1358 If the first character of @var{sectionpattern} is the exclamation
1359 point (!) then matching sections will not have their relocation
1360 removed even if an earlier use of @option{--remove-relocations} on the
1361 same command line would otherwise cause the relocations to be removed.
1362 For example:
1363
1364 @smallexample
1365 --remove-relocations=.text.* --remove-relocations=!.text.foo
1366 @end smallexample
1367
1368 will remove all relocations for sections matching the pattern
1369 '.text.*', but will not remove relocations for the section
1370 '.text.foo'.
1371
1372 @item -S
1373 @itemx --strip-all
1374 Do not copy relocation and symbol information from the source file.
1375
1376 @item -g
1377 @itemx --strip-debug
1378 Do not copy debugging symbols or sections from the source file.
1379
1380 @item --strip-unneeded
1381 Strip all symbols that are not needed for relocation processing.
1382
1383 @item -K @var{symbolname}
1384 @itemx --keep-symbol=@var{symbolname}
1385 When stripping symbols, keep symbol @var{symbolname} even if it would
1386 normally be stripped. This option may be given more than once.
1387
1388 @item -N @var{symbolname}
1389 @itemx --strip-symbol=@var{symbolname}
1390 Do not copy symbol @var{symbolname} from the source file. This option
1391 may be given more than once.
1392
1393 @item --strip-unneeded-symbol=@var{symbolname}
1394 Do not copy symbol @var{symbolname} from the source file unless it is needed
1395 by a relocation. This option may be given more than once.
1396
1397 @item -G @var{symbolname}
1398 @itemx --keep-global-symbol=@var{symbolname}
1399 Keep only symbol @var{symbolname} global. Make all other symbols local
1400 to the file, so that they are not visible externally. This option may
1401 be given more than once. Note: this option cannot be used in
1402 conjunction with the @option{--globalize-symbol} or
1403 @option{--globalize-symbols} options.
1404
1405 @item --localize-hidden
1406 In an ELF object, mark all symbols that have hidden or internal visibility
1407 as local. This option applies on top of symbol-specific localization options
1408 such as @option{-L}.
1409
1410 @item -L @var{symbolname}
1411 @itemx --localize-symbol=@var{symbolname}
1412 Convert a global or weak symbol called @var{symbolname} into a local
1413 symbol, so that it is not visible externally. This option may be
1414 given more than once. Note - unique symbols are not converted.
1415
1416 @item -W @var{symbolname}
1417 @itemx --weaken-symbol=@var{symbolname}
1418 Make symbol @var{symbolname} weak. This option may be given more than once.
1419
1420 @item --globalize-symbol=@var{symbolname}
1421 Give symbol @var{symbolname} global scoping so that it is visible
1422 outside of the file in which it is defined. This option may be given
1423 more than once. Note: this option cannot be used in conjunction with
1424 the @option{-G} or @option{--keep-global-symbol} options.
1425
1426 @item -w
1427 @itemx --wildcard
1428 Permit regular expressions in @var{symbolname}s used in other command
1429 line options. The question mark (?), asterisk (*), backslash (\) and
1430 square brackets ([]) operators can be used anywhere in the symbol
1431 name. If the first character of the symbol name is the exclamation
1432 point (!) then the sense of the switch is reversed for that symbol.
1433 For example:
1434
1435 @smallexample
1436 -w -W !foo -W fo*
1437 @end smallexample
1438
1439 would cause objcopy to weaken all symbols that start with ``fo''
1440 except for the symbol ``foo''.
1441
1442 @item -x
1443 @itemx --discard-all
1444 Do not copy non-global symbols from the source file.
1445 @c FIXME any reason to prefer "non-global" to "local" here?
1446
1447 @item -X
1448 @itemx --discard-locals
1449 Do not copy compiler-generated local symbols.
1450 (These usually start with @samp{L} or @samp{.}.)
1451
1452 @item -b @var{byte}
1453 @itemx --byte=@var{byte}
1454 If interleaving has been enabled via the @option{--interleave} option
1455 then start the range of bytes to keep at the @var{byte}th byte.
1456 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1457 @var{breadth} is the value given by the @option{--interleave} option.
1458
1459 @item -i [@var{breadth}]
1460 @itemx --interleave[=@var{breadth}]
1461 Only copy a range out of every @var{breadth} bytes. (Header data is
1462 not affected). Select which byte in the range begins the copy with
1463 the @option{--byte} option. Select the width of the range with the
1464 @option{--interleave-width} option.
1465
1466 This option is useful for creating files to program @sc{rom}. It is
1467 typically used with an @code{srec} output target. Note that
1468 @command{objcopy} will complain if you do not specify the
1469 @option{--byte} option as well.
1470
1471 The default interleave breadth is 4, so with @option{--byte} set to 0,
1472 @command{objcopy} would copy the first byte out of every four bytes
1473 from the input to the output.
1474
1475 @item --interleave-width=@var{width}
1476 When used with the @option{--interleave} option, copy @var{width}
1477 bytes at a time. The start of the range of bytes to be copied is set
1478 by the @option{--byte} option, and the extent of the range is set with
1479 the @option{--interleave} option.
1480
1481 The default value for this option is 1. The value of @var{width} plus
1482 the @var{byte} value set by the @option{--byte} option must not exceed
1483 the interleave breadth set by the @option{--interleave} option.
1484
1485 This option can be used to create images for two 16-bit flashes interleaved
1486 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1487 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1488 commands. If the input was '12345678' then the outputs would be
1489 '1256' and '3478' respectively.
1490
1491 @item -p
1492 @itemx --preserve-dates
1493 Set the access and modification dates of the output file to be the same
1494 as those of the input file.
1495
1496 @item -D
1497 @itemx --enable-deterministic-archives
1498 @cindex deterministic archives
1499 @kindex --enable-deterministic-archives
1500 Operate in @emph{deterministic} mode. When copying archive members
1501 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1502 and use consistent file modes for all files.
1503
1504 If @file{binutils} was configured with
1505 @option{--enable-deterministic-archives}, then this mode is on by default.
1506 It can be disabled with the @samp{-U} option, below.
1507
1508 @item -U
1509 @itemx --disable-deterministic-archives
1510 @cindex deterministic archives
1511 @kindex --enable-deterministic-archives
1512 Do @emph{not} operate in @emph{deterministic} mode. This is the
1513 inverse of the @option{-D} option, above: when copying archive members
1514 and writing the archive index, use their actual UID, GID, timestamp,
1515 and file mode values.
1516
1517 This is the default unless @file{binutils} was configured with
1518 @option{--enable-deterministic-archives}.
1519
1520 @item --debugging
1521 Convert debugging information, if possible. This is not the default
1522 because only certain debugging formats are supported, and the
1523 conversion process can be time consuming.
1524
1525 @item --gap-fill @var{val}
1526 Fill gaps between sections with @var{val}. This operation applies to
1527 the @emph{load address} (LMA) of the sections. It is done by increasing
1528 the size of the section with the lower address, and filling in the extra
1529 space created with @var{val}.
1530
1531 @item --pad-to @var{address}
1532 Pad the output file up to the load address @var{address}. This is
1533 done by increasing the size of the last section. The extra space is
1534 filled in with the value specified by @option{--gap-fill} (default zero).
1535
1536 @item --set-start @var{val}
1537 Set the start address of the new file to @var{val}. Not all object file
1538 formats support setting the start address.
1539
1540 @item --change-start @var{incr}
1541 @itemx --adjust-start @var{incr}
1542 @cindex changing start address
1543 Change the start address by adding @var{incr}. Not all object file
1544 formats support setting the start address.
1545
1546 @item --change-addresses @var{incr}
1547 @itemx --adjust-vma @var{incr}
1548 @cindex changing object addresses
1549 Change the VMA and LMA addresses of all sections, as well as the start
1550 address, by adding @var{incr}. Some object file formats do not permit
1551 section addresses to be changed arbitrarily. Note that this does not
1552 relocate the sections; if the program expects sections to be loaded at a
1553 certain address, and this option is used to change the sections such
1554 that they are loaded at a different address, the program may fail.
1555
1556 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1557 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1558 @cindex changing section address
1559 Set or change both the VMA address and the LMA address of any section
1560 matching @var{sectionpattern}. If @samp{=} is used, the section
1561 address is set to @var{val}. Otherwise, @var{val} is added to or
1562 subtracted from the section address. See the comments under
1563 @option{--change-addresses}, above. If @var{sectionpattern} does not
1564 match any sections in the input file, a warning will be issued, unless
1565 @option{--no-change-warnings} is used.
1566
1567 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1568 @cindex changing section LMA
1569 Set or change the LMA address of any sections matching
1570 @var{sectionpattern}. The LMA address is the address where the
1571 section will be loaded into memory at program load time. Normally
1572 this is the same as the VMA address, which is the address of the
1573 section at program run time, but on some systems, especially those
1574 where a program is held in ROM, the two can be different. If @samp{=}
1575 is used, the section address is set to @var{val}. Otherwise,
1576 @var{val} is added to or subtracted from the section address. See the
1577 comments under @option{--change-addresses}, above. If
1578 @var{sectionpattern} does not match any sections in the input file, a
1579 warning will be issued, unless @option{--no-change-warnings} is used.
1580
1581 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1582 @cindex changing section VMA
1583 Set or change the VMA address of any section matching
1584 @var{sectionpattern}. The VMA address is the address where the
1585 section will be located once the program has started executing.
1586 Normally this is the same as the LMA address, which is the address
1587 where the section will be loaded into memory, but on some systems,
1588 especially those where a program is held in ROM, the two can be
1589 different. If @samp{=} is used, the section address is set to
1590 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1591 section address. See the comments under @option{--change-addresses},
1592 above. If @var{sectionpattern} does not match any sections in the
1593 input file, a warning will be issued, unless
1594 @option{--no-change-warnings} is used.
1595
1596 @item --change-warnings
1597 @itemx --adjust-warnings
1598 If @option{--change-section-address} or @option{--change-section-lma} or
1599 @option{--change-section-vma} is used, and the section pattern does not
1600 match any sections, issue a warning. This is the default.
1601
1602 @item --no-change-warnings
1603 @itemx --no-adjust-warnings
1604 Do not issue a warning if @option{--change-section-address} or
1605 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1606 if the section pattern does not match any sections.
1607
1608 @item --set-section-flags @var{sectionpattern}=@var{flags}
1609 Set the flags for any sections matching @var{sectionpattern}. The
1610 @var{flags} argument is a comma separated string of flag names. The
1611 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1612 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1613 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1614 for a section which does not have contents, but it is not meaningful
1615 to clear the @samp{contents} flag of a section which does have
1616 contents--just remove the section instead. Not all flags are
1617 meaningful for all object file formats.
1618
1619 @item --add-section @var{sectionname}=@var{filename}
1620 Add a new section named @var{sectionname} while copying the file. The
1621 contents of the new section are taken from the file @var{filename}. The
1622 size of the section will be the size of the file. This option only
1623 works on file formats which can support sections with arbitrary names.
1624 Note - it may be necessary to use the @option{--set-section-flags}
1625 option to set the attributes of the newly created section.
1626
1627 @item --dump-section @var{sectionname}=@var{filename}
1628 Place the contents of section named @var{sectionname} into the file
1629 @var{filename}, overwriting any contents that may have been there
1630 previously. This option is the inverse of @option{--add-section}.
1631 This option is similar to the @option{--only-section} option except
1632 that it does not create a formatted file, it just dumps the contents
1633 as raw binary data, without applying any relocations. The option can
1634 be specified more than once.
1635
1636 @item --update-section @var{sectionname}=@var{filename}
1637 Replace the existing contents of a section named @var{sectionname}
1638 with the contents of file @var{filename}. The size of the section
1639 will be adjusted to the size of the file. The section flags for
1640 @var{sectionname} will be unchanged. For ELF format files the section
1641 to segment mapping will also remain unchanged, something which is not
1642 possible using @option{--remove-section} followed by
1643 @option{--add-section}. The option can be specified more than once.
1644
1645 Note - it is possible to use @option{--rename-section} and
1646 @option{--update-section} to both update and rename a section from one
1647 command line. In this case, pass the original section name to
1648 @option{--update-section}, and the original and new section names to
1649 @option{--rename-section}.
1650
1651 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1652 Add a new symbol named @var{name} while copying the file. This option may be
1653 specified multiple times. If the @var{section} is given, the symbol will be
1654 associated with and relative to that section, otherwise it will be an ABS
1655 symbol. Specifying an undefined section will result in a fatal error. There
1656 is no check for the value, it will be taken as specified. Symbol flags can
1657 be specified and not all flags will be meaningful for all object file
1658 formats. By default, the symbol will be global. The special flag
1659 'before=@var{othersym}' will insert the new symbol in front of the specified
1660 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1661 symbol table in the order they appear.
1662
1663 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1664 Rename a section from @var{oldname} to @var{newname}, optionally
1665 changing the section's flags to @var{flags} in the process. This has
1666 the advantage over using a linker script to perform the rename in that
1667 the output stays as an object file and does not become a linked
1668 executable.
1669
1670 This option is particularly helpful when the input format is binary,
1671 since this will always create a section called .data. If for example,
1672 you wanted instead to create a section called .rodata containing binary
1673 data you could use the following command line to achieve it:
1674
1675 @smallexample
1676 objcopy -I binary -O <output_format> -B <architecture> \
1677 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1678 <input_binary_file> <output_object_file>
1679 @end smallexample
1680
1681 @item --long-section-names @{enable,disable,keep@}
1682 Controls the handling of long section names when processing @code{COFF}
1683 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1684 is to preserve long section names if any are present in the input file.
1685 The @samp{enable} and @samp{disable} options forcibly enable or disable
1686 the use of long section names in the output object; when @samp{disable}
1687 is in effect, any long section names in the input object will be truncated.
1688 The @samp{enable} option will only emit long section names if any are
1689 present in the inputs; this is mostly the same as @samp{keep}, but it
1690 is left undefined whether the @samp{enable} option might force the
1691 creation of an empty string table in the output file.
1692
1693 @item --change-leading-char
1694 Some object file formats use special characters at the start of
1695 symbols. The most common such character is underscore, which compilers
1696 often add before every symbol. This option tells @command{objcopy} to
1697 change the leading character of every symbol when it converts between
1698 object file formats. If the object file formats use the same leading
1699 character, this option has no effect. Otherwise, it will add a
1700 character, or remove a character, or change a character, as
1701 appropriate.
1702
1703 @item --remove-leading-char
1704 If the first character of a global symbol is a special symbol leading
1705 character used by the object file format, remove the character. The
1706 most common symbol leading character is underscore. This option will
1707 remove a leading underscore from all global symbols. This can be useful
1708 if you want to link together objects of different file formats with
1709 different conventions for symbol names. This is different from
1710 @option{--change-leading-char} because it always changes the symbol name
1711 when appropriate, regardless of the object file format of the output
1712 file.
1713
1714 @item --reverse-bytes=@var{num}
1715 Reverse the bytes in a section with output contents. A section length must
1716 be evenly divisible by the value given in order for the swap to be able to
1717 take place. Reversing takes place before the interleaving is performed.
1718
1719 This option is used typically in generating ROM images for problematic
1720 target systems. For example, on some target boards, the 32-bit words
1721 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1722 regardless of the CPU byte order. Depending on the programming model, the
1723 endianness of the ROM may need to be modified.
1724
1725 Consider a simple file with a section containing the following eight
1726 bytes: @code{12345678}.
1727
1728 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1729 output file would be ordered @code{21436587}.
1730
1731 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1732 output file would be ordered @code{43218765}.
1733
1734 By using @samp{--reverse-bytes=2} for the above example, followed by
1735 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1736 output file would be ordered @code{34127856}.
1737
1738 @item --srec-len=@var{ival}
1739 Meaningful only for srec output. Set the maximum length of the Srecords
1740 being produced to @var{ival}. This length covers both address, data and
1741 crc fields.
1742
1743 @item --srec-forceS3
1744 Meaningful only for srec output. Avoid generation of S1/S2 records,
1745 creating S3-only record format.
1746
1747 @item --redefine-sym @var{old}=@var{new}
1748 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1749 when one is trying link two things together for which you have no
1750 source, and there are name collisions.
1751
1752 @item --redefine-syms=@var{filename}
1753 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1754 listed in the file @var{filename}. @var{filename} is simply a flat file,
1755 with one symbol pair per line. Line comments may be introduced by the hash
1756 character. This option may be given more than once.
1757
1758 @item --weaken
1759 Change all global symbols in the file to be weak. This can be useful
1760 when building an object which will be linked against other objects using
1761 the @option{-R} option to the linker. This option is only effective when
1762 using an object file format which supports weak symbols.
1763
1764 @item --keep-symbols=@var{filename}
1765 Apply @option{--keep-symbol} option to each symbol listed in the file
1766 @var{filename}. @var{filename} is simply a flat file, with one symbol
1767 name per line. Line comments may be introduced by the hash character.
1768 This option may be given more than once.
1769
1770 @item --strip-symbols=@var{filename}
1771 Apply @option{--strip-symbol} option to each symbol listed in the file
1772 @var{filename}. @var{filename} is simply a flat file, with one symbol
1773 name per line. Line comments may be introduced by the hash character.
1774 This option may be given more than once.
1775
1776 @item --strip-unneeded-symbols=@var{filename}
1777 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1778 the file @var{filename}. @var{filename} is simply a flat file, with one
1779 symbol name per line. Line comments may be introduced by the hash
1780 character. This option may be given more than once.
1781
1782 @item --keep-global-symbols=@var{filename}
1783 Apply @option{--keep-global-symbol} option to each symbol listed in the
1784 file @var{filename}. @var{filename} is simply a flat file, with one
1785 symbol name per line. Line comments may be introduced by the hash
1786 character. This option may be given more than once.
1787
1788 @item --localize-symbols=@var{filename}
1789 Apply @option{--localize-symbol} option to each symbol listed in the file
1790 @var{filename}. @var{filename} is simply a flat file, with one symbol
1791 name per line. Line comments may be introduced by the hash character.
1792 This option may be given more than once.
1793
1794 @item --globalize-symbols=@var{filename}
1795 Apply @option{--globalize-symbol} option to each symbol listed in the file
1796 @var{filename}. @var{filename} is simply a flat file, with one symbol
1797 name per line. Line comments may be introduced by the hash character.
1798 This option may be given more than once. Note: this option cannot be
1799 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1800 options.
1801
1802 @item --weaken-symbols=@var{filename}
1803 Apply @option{--weaken-symbol} option to each symbol listed in the file
1804 @var{filename}. @var{filename} is simply a flat file, with one symbol
1805 name per line. Line comments may be introduced by the hash character.
1806 This option may be given more than once.
1807
1808 @item --alt-machine-code=@var{index}
1809 If the output architecture has alternate machine codes, use the
1810 @var{index}th code instead of the default one. This is useful in case
1811 a machine is assigned an official code and the tool-chain adopts the
1812 new code, but other applications still depend on the original code
1813 being used. For ELF based architectures if the @var{index}
1814 alternative does not exist then the value is treated as an absolute
1815 number to be stored in the e_machine field of the ELF header.
1816
1817 @item --writable-text
1818 Mark the output text as writable. This option isn't meaningful for all
1819 object file formats.
1820
1821 @item --readonly-text
1822 Make the output text write protected. This option isn't meaningful for all
1823 object file formats.
1824
1825 @item --pure
1826 Mark the output file as demand paged. This option isn't meaningful for all
1827 object file formats.
1828
1829 @item --impure
1830 Mark the output file as impure. This option isn't meaningful for all
1831 object file formats.
1832
1833 @item --prefix-symbols=@var{string}
1834 Prefix all symbols in the output file with @var{string}.
1835
1836 @item --prefix-sections=@var{string}
1837 Prefix all section names in the output file with @var{string}.
1838
1839 @item --prefix-alloc-sections=@var{string}
1840 Prefix all the names of all allocated sections in the output file with
1841 @var{string}.
1842
1843 @item --add-gnu-debuglink=@var{path-to-file}
1844 Creates a .gnu_debuglink section which contains a reference to
1845 @var{path-to-file} and adds it to the output file. Note: the file at
1846 @var{path-to-file} must exist. Part of the process of adding the
1847 .gnu_debuglink section involves embedding a checksum of the contents
1848 of the debug info file into the section.
1849
1850 If the debug info file is built in one location but it is going to be
1851 installed at a later time into a different location then do not use
1852 the path to the installed location. The @option{--add-gnu-debuglink}
1853 option will fail because the installed file does not exist yet.
1854 Instead put the debug info file in the current directory and use the
1855 @option{--add-gnu-debuglink} option without any directory components,
1856 like this:
1857
1858 @smallexample
1859 objcopy --add-gnu-debuglink=foo.debug
1860 @end smallexample
1861
1862 At debug time the debugger will attempt to look for the separate debug
1863 info file in a set of known locations. The exact set of these
1864 locations varies depending upon the distribution being used, but it
1865 typically includes:
1866
1867 @table @code
1868
1869 @item * The same directory as the executable.
1870
1871 @item * A sub-directory of the directory containing the executable
1872 called .debug
1873
1874 @item * A global debug directory such as /usr/lib/debug.
1875 @end table
1876
1877 As long as the debug info file has been installed into one of these
1878 locations before the debugger is run everything should work
1879 correctly.
1880
1881 @item --keep-file-symbols
1882 When stripping a file, perhaps with @option{--strip-debug} or
1883 @option{--strip-unneeded}, retain any symbols specifying source file names,
1884 which would otherwise get stripped.
1885
1886 @item --only-keep-debug
1887 Strip a file, removing contents of any sections that would not be
1888 stripped by @option{--strip-debug} and leaving the debugging sections
1889 intact. In ELF files, this preserves all note sections in the output.
1890
1891 Note - the section headers of the stripped sections are preserved,
1892 including their sizes, but the contents of the section are discarded.
1893 The section headers are preserved so that other tools can match up the
1894 debuginfo file with the real executable, even if that executable has
1895 been relocated to a different address space.
1896
1897 The intention is that this option will be used in conjunction with
1898 @option{--add-gnu-debuglink} to create a two part executable. One a
1899 stripped binary which will occupy less space in RAM and in a
1900 distribution and the second a debugging information file which is only
1901 needed if debugging abilities are required. The suggested procedure
1902 to create these files is as follows:
1903
1904 @enumerate
1905 @item Link the executable as normal. Assuming that it is called
1906 @code{foo} then...
1907 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1908 create a file containing the debugging info.
1909 @item Run @code{objcopy --strip-debug foo} to create a
1910 stripped executable.
1911 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1912 to add a link to the debugging info into the stripped executable.
1913 @end enumerate
1914
1915 Note---the choice of @code{.dbg} as an extension for the debug info
1916 file is arbitrary. Also the @code{--only-keep-debug} step is
1917 optional. You could instead do this:
1918
1919 @enumerate
1920 @item Link the executable as normal.
1921 @item Copy @code{foo} to @code{foo.full}
1922 @item Run @code{objcopy --strip-debug foo}
1923 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1924 @end enumerate
1925
1926 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1927 full executable. It does not have to be a file created by the
1928 @option{--only-keep-debug} switch.
1929
1930 Note---this switch is only intended for use on fully linked files. It
1931 does not make sense to use it on object files where the debugging
1932 information may be incomplete. Besides the gnu_debuglink feature
1933 currently only supports the presence of one filename containing
1934 debugging information, not multiple filenames on a one-per-object-file
1935 basis.
1936
1937 @item --strip-dwo
1938 Remove the contents of all DWARF .dwo sections, leaving the
1939 remaining debugging sections and all symbols intact.
1940 This option is intended for use by the compiler as part of
1941 the @option{-gsplit-dwarf} option, which splits debug information
1942 between the .o file and a separate .dwo file. The compiler
1943 generates all debug information in the same file, then uses
1944 the @option{--extract-dwo} option to copy the .dwo sections to
1945 the .dwo file, then the @option{--strip-dwo} option to remove
1946 those sections from the original .o file.
1947
1948 @item --extract-dwo
1949 Extract the contents of all DWARF .dwo sections. See the
1950 @option{--strip-dwo} option for more information.
1951
1952 @item --file-alignment @var{num}
1953 Specify the file alignment. Sections in the file will always begin at
1954 file offsets which are multiples of this number. This defaults to
1955 512.
1956 [This option is specific to PE targets.]
1957
1958 @item --heap @var{reserve}
1959 @itemx --heap @var{reserve},@var{commit}
1960 Specify the number of bytes of memory to reserve (and optionally commit)
1961 to be used as heap for this program.
1962 [This option is specific to PE targets.]
1963
1964 @item --image-base @var{value}
1965 Use @var{value} as the base address of your program or dll. This is
1966 the lowest memory location that will be used when your program or dll
1967 is loaded. To reduce the need to relocate and improve performance of
1968 your dlls, each should have a unique base address and not overlap any
1969 other dlls. The default is 0x400000 for executables, and 0x10000000
1970 for dlls.
1971 [This option is specific to PE targets.]
1972
1973 @item --section-alignment @var{num}
1974 Sets the section alignment. Sections in memory will always begin at
1975 addresses which are a multiple of this number. Defaults to 0x1000.
1976 [This option is specific to PE targets.]
1977
1978 @item --stack @var{reserve}
1979 @itemx --stack @var{reserve},@var{commit}
1980 Specify the number of bytes of memory to reserve (and optionally commit)
1981 to be used as stack for this program.
1982 [This option is specific to PE targets.]
1983
1984 @item --subsystem @var{which}
1985 @itemx --subsystem @var{which}:@var{major}
1986 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1987 Specifies the subsystem under which your program will execute. The
1988 legal values for @var{which} are @code{native}, @code{windows},
1989 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1990 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1991 the subsystem version also. Numeric values are also accepted for
1992 @var{which}.
1993 [This option is specific to PE targets.]
1994
1995 @item --extract-symbol
1996 Keep the file's section flags and symbols but remove all section data.
1997 Specifically, the option:
1998
1999 @itemize
2000 @item removes the contents of all sections;
2001 @item sets the size of every section to zero; and
2002 @item sets the file's start address to zero.
2003 @end itemize
2004
2005 This option is used to build a @file{.sym} file for a VxWorks kernel.
2006 It can also be a useful way of reducing the size of a @option{--just-symbols}
2007 linker input file.
2008
2009 @item --compress-debug-sections
2010 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2011 ELF ABI. Note - if compression would actually make a section
2012 @emph{larger}, then it is not compressed.
2013
2014 @item --compress-debug-sections=none
2015 @itemx --compress-debug-sections=zlib
2016 @itemx --compress-debug-sections=zlib-gnu
2017 @itemx --compress-debug-sections=zlib-gabi
2018 For ELF files, these options control how DWARF debug sections are
2019 compressed. @option{--compress-debug-sections=none} is equivalent
2020 to @option{--decompress-debug-sections}.
2021 @option{--compress-debug-sections=zlib} and
2022 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2023 @option{--compress-debug-sections}.
2024 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
2025 sections using zlib. The debug sections are renamed to begin with
2026 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
2027 actually make a section @emph{larger}, then it is not compressed nor
2028 renamed.
2029
2030 @item --decompress-debug-sections
2031 Decompress DWARF debug sections using zlib. The original section
2032 names of the compressed sections are restored.
2033
2034 @item --elf-stt-common=yes
2035 @itemx --elf-stt-common=no
2036 For ELF files, these options control whether common symbols should be
2037 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2038 @option{--elf-stt-common=yes} converts common symbol type to
2039 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2040 type to @code{STT_OBJECT}.
2041
2042 @item --merge-notes
2043 @itemx --no-merge-notes
2044 For ELF files, attempt (or do not attempt) to reduce the size of any
2045 SHT_NOTE type sections by removing duplicate notes.
2046
2047 @item -V
2048 @itemx --version
2049 Show the version number of @command{objcopy}.
2050
2051 @item -v
2052 @itemx --verbose
2053 Verbose output: list all object files modified. In the case of
2054 archives, @samp{objcopy -V} lists all members of the archive.
2055
2056 @item --help
2057 Show a summary of the options to @command{objcopy}.
2058
2059 @item --info
2060 Display a list showing all architectures and object formats available.
2061 @end table
2062
2063 @c man end
2064
2065 @ignore
2066 @c man begin SEEALSO objcopy
2067 ld(1), objdump(1), and the Info entries for @file{binutils}.
2068 @c man end
2069 @end ignore
2070
2071 @node objdump
2072 @chapter objdump
2073
2074 @cindex object file information
2075 @kindex objdump
2076
2077 @c man title objdump display information from object files.
2078
2079 @smallexample
2080 @c man begin SYNOPSIS objdump
2081 objdump [@option{-a}|@option{--archive-headers}]
2082 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2083 [@option{-C}|@option{--demangle}[=@var{style}] ]
2084 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2085 [@option{-D}|@option{--disassemble-all}]
2086 [@option{-z}|@option{--disassemble-zeroes}]
2087 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2088 [@option{-f}|@option{--file-headers}]
2089 [@option{-F}|@option{--file-offsets}]
2090 [@option{--file-start-context}]
2091 [@option{-g}|@option{--debugging}]
2092 [@option{-e}|@option{--debugging-tags}]
2093 [@option{-h}|@option{--section-headers}|@option{--headers}]
2094 [@option{-i}|@option{--info}]
2095 [@option{-j} @var{section}|@option{--section=}@var{section}]
2096 [@option{-l}|@option{--line-numbers}]
2097 [@option{-S}|@option{--source}]
2098 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2099 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2100 [@option{-p}|@option{--private-headers}]
2101 [@option{-P} @var{options}|@option{--private=}@var{options}]
2102 [@option{-r}|@option{--reloc}]
2103 [@option{-R}|@option{--dynamic-reloc}]
2104 [@option{-s}|@option{--full-contents}]
2105 [@option{-W[lLiaprmfFsoRtUuTgAckK]}|
2106 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]]
2107 [@option{-G}|@option{--stabs}]
2108 [@option{-t}|@option{--syms}]
2109 [@option{-T}|@option{--dynamic-syms}]
2110 [@option{-x}|@option{--all-headers}]
2111 [@option{-w}|@option{--wide}]
2112 [@option{--start-address=}@var{address}]
2113 [@option{--stop-address=}@var{address}]
2114 [@option{--prefix-addresses}]
2115 [@option{--[no-]show-raw-insn}]
2116 [@option{--adjust-vma=}@var{offset}]
2117 [@option{--dwarf-depth=@var{n}}]
2118 [@option{--dwarf-start=@var{n}}]
2119 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2120 [@option{--special-syms}]
2121 [@option{--prefix=}@var{prefix}]
2122 [@option{--prefix-strip=}@var{level}]
2123 [@option{--insn-width=}@var{width}]
2124 [@option{-V}|@option{--version}]
2125 [@option{-H}|@option{--help}]
2126 @var{objfile}@dots{}
2127 @c man end
2128 @end smallexample
2129
2130 @c man begin DESCRIPTION objdump
2131
2132 @command{objdump} displays information about one or more object files.
2133 The options control what particular information to display. This
2134 information is mostly useful to programmers who are working on the
2135 compilation tools, as opposed to programmers who just want their
2136 program to compile and work.
2137
2138 @var{objfile}@dots{} are the object files to be examined. When you
2139 specify archives, @command{objdump} shows information on each of the member
2140 object files.
2141
2142 @c man end
2143
2144 @c man begin OPTIONS objdump
2145
2146 The long and short forms of options, shown here as alternatives, are
2147 equivalent. At least one option from the list
2148 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2149
2150 @table @env
2151 @item -a
2152 @itemx --archive-header
2153 @cindex archive headers
2154 If any of the @var{objfile} files are archives, display the archive
2155 header information (in a format similar to @samp{ls -l}). Besides the
2156 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2157 the object file format of each archive member.
2158
2159 @item --adjust-vma=@var{offset}
2160 @cindex section addresses in objdump
2161 @cindex VMA in objdump
2162 When dumping information, first add @var{offset} to all the section
2163 addresses. This is useful if the section addresses do not correspond to
2164 the symbol table, which can happen when putting sections at particular
2165 addresses when using a format which can not represent section addresses,
2166 such as a.out.
2167
2168 @item -b @var{bfdname}
2169 @itemx --target=@var{bfdname}
2170 @cindex object code format
2171 Specify that the object-code format for the object files is
2172 @var{bfdname}. This option may not be necessary; @var{objdump} can
2173 automatically recognize many formats.
2174
2175 For example,
2176 @example
2177 objdump -b oasys -m vax -h fu.o
2178 @end example
2179 @noindent
2180 displays summary information from the section headers (@option{-h}) of
2181 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2182 file in the format produced by Oasys compilers. You can list the
2183 formats available with the @option{-i} option.
2184 @xref{Target Selection}, for more information.
2185
2186 @item -C
2187 @itemx --demangle[=@var{style}]
2188 @cindex demangling in objdump
2189 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2190 Besides removing any initial underscore prepended by the system, this
2191 makes C++ function names readable. Different compilers have different
2192 mangling styles. The optional demangling style argument can be used to
2193 choose an appropriate demangling style for your compiler. @xref{c++filt},
2194 for more information on demangling.
2195
2196 @item --recurse-limit
2197 @itemx --no-recurse-limit
2198 @itemx --recursion-limit
2199 @itemx --no-recursion-limit
2200 Enables or disables a limit on the amount of recursion performed
2201 whilst demangling strings. Since the name mangling formats allow for
2202 an inifinite level of recursion it is possible to create strings whose
2203 decoding will exhaust the amount of stack space available on the host
2204 machine, triggering a memory fault. The limit tries to prevent this
2205 from happening by restricting recursion to 2048 levels of nesting.
2206
2207 The default is for this limit to be enabled, but disabling it may be
2208 necessary in order to demangle truly complicated names. Note however
2209 that if the recursion limit is disabled then stack exhaustion is
2210 possible and any bug reports about such an event will be rejected.
2211
2212 @item -g
2213 @itemx --debugging
2214 Display debugging information. This attempts to parse STABS
2215 debugging format information stored in the file and print it out using
2216 a C like syntax. If no STABS debuging was found this option
2217 falls back on the @option{-W} option to print any DWARF information in
2218 the file.
2219
2220 @item -e
2221 @itemx --debugging-tags
2222 Like @option{-g}, but the information is generated in a format compatible
2223 with ctags tool.
2224
2225 @item -d
2226 @itemx --disassemble
2227 @itemx --disassemble=@var{symbol}
2228 @cindex disassembling object code
2229 @cindex machine instructions
2230 Display the assembler mnemonics for the machine instructions from the
2231 input file. This option only disassembles those sections which are
2232 expected to contain instructions. If the optional @var{symbol}
2233 argument is given, then display the assembler mnemonics starting at
2234 @var{symbol}. If @var{symbol} is a function name then disassembly
2235 will stop at the end of the function, otherwise it will stop when the
2236 next symbol is encountered. If there are no matches for @var{symbol}
2237 then nothing will be displayed.
2238
2239 @item -D
2240 @itemx --disassemble-all
2241 Like @option{-d}, but disassemble the contents of all sections, not just
2242 those expected to contain instructions.
2243
2244 This option also has a subtle effect on the disassembly of
2245 instructions in code sections. When option @option{-d} is in effect
2246 objdump will assume that any symbols present in a code section occur
2247 on the boundary between instructions and it will refuse to disassemble
2248 across such a boundary. When option @option{-D} is in effect however
2249 this assumption is supressed. This means that it is possible for the
2250 output of @option{-d} and @option{-D} to differ if, for example, data
2251 is stored in code sections.
2252
2253 If the target is an ARM architecture this switch also has the effect
2254 of forcing the disassembler to decode pieces of data found in code
2255 sections as if they were instructions.
2256
2257 @item --prefix-addresses
2258 When disassembling, print the complete address on each line. This is
2259 the older disassembly format.
2260
2261 @item -EB
2262 @itemx -EL
2263 @itemx --endian=@{big|little@}
2264 @cindex endianness
2265 @cindex disassembly endianness
2266 Specify the endianness of the object files. This only affects
2267 disassembly. This can be useful when disassembling a file format which
2268 does not describe endianness information, such as S-records.
2269
2270 @item -f
2271 @itemx --file-headers
2272 @cindex object file header
2273 Display summary information from the overall header of
2274 each of the @var{objfile} files.
2275
2276 @item -F
2277 @itemx --file-offsets
2278 @cindex object file offsets
2279 When disassembling sections, whenever a symbol is displayed, also
2280 display the file offset of the region of data that is about to be
2281 dumped. If zeroes are being skipped, then when disassembly resumes,
2282 tell the user how many zeroes were skipped and the file offset of the
2283 location from where the disassembly resumes. When dumping sections,
2284 display the file offset of the location from where the dump starts.
2285
2286 @item --file-start-context
2287 @cindex source code context
2288 Specify that when displaying interlisted source code/disassembly
2289 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2290 context to the start of the file.
2291
2292 @item -h
2293 @itemx --section-headers
2294 @itemx --headers
2295 @cindex section headers
2296 Display summary information from the section headers of the
2297 object file.
2298
2299 File segments may be relocated to nonstandard addresses, for example by
2300 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2301 @command{ld}. However, some object file formats, such as a.out, do not
2302 store the starting address of the file segments. In those situations,
2303 although @command{ld} relocates the sections correctly, using @samp{objdump
2304 -h} to list the file section headers cannot show the correct addresses.
2305 Instead, it shows the usual addresses, which are implicit for the
2306 target.
2307
2308 Note, in some cases it is possible for a section to have both the
2309 READONLY and the NOREAD attributes set. In such cases the NOREAD
2310 attribute takes precedence, but @command{objdump} will report both
2311 since the exact setting of the flag bits might be important.
2312
2313 @item -H
2314 @itemx --help
2315 Print a summary of the options to @command{objdump} and exit.
2316
2317 @item -i
2318 @itemx --info
2319 @cindex architectures available
2320 @cindex object formats available
2321 Display a list showing all architectures and object formats available
2322 for specification with @option{-b} or @option{-m}.
2323
2324 @item -j @var{name}
2325 @itemx --section=@var{name}
2326 @cindex section information
2327 Display information only for section @var{name}.
2328
2329 @item -l
2330 @itemx --line-numbers
2331 @cindex source filenames for object files
2332 Label the display (using debugging information) with the filename and
2333 source line numbers corresponding to the object code or relocs shown.
2334 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2335
2336 @item -m @var{machine}
2337 @itemx --architecture=@var{machine}
2338 @cindex architecture
2339 @cindex disassembly architecture
2340 Specify the architecture to use when disassembling object files. This
2341 can be useful when disassembling object files which do not describe
2342 architecture information, such as S-records. You can list the available
2343 architectures with the @option{-i} option.
2344
2345 If the target is an ARM architecture then this switch has an
2346 additional effect. It restricts the disassembly to only those
2347 instructions supported by the architecture specified by @var{machine}.
2348 If it is necessary to use this switch because the input file does not
2349 contain any architecture information, but it is also desired to
2350 disassemble all the instructions use @option{-marm}.
2351
2352 @item -M @var{options}
2353 @itemx --disassembler-options=@var{options}
2354 Pass target specific information to the disassembler. Only supported on
2355 some targets. If it is necessary to specify more than one
2356 disassembler option then multiple @option{-M} options can be used or
2357 can be placed together into a comma separated list.
2358
2359 For ARC, @option{dsp} controls the printing of DSP instructions,
2360 @option{spfp} selects the printing of FPX single precision FP
2361 instructions, @option{dpfp} selects the printing of FPX double
2362 precision FP instructions, @option{quarkse_em} selects the printing of
2363 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2364 of double precision assist instructions, @option{fpus} selects the
2365 printing of FPU single precision FP instructions, while @option{fpud}
2366 selects the printing of FPU double precision FP instructions.
2367 Additionally, one can choose to have all the immediates printed in
2368 hexadecimal using @option{hex}. By default, the short immediates are
2369 printed using the decimal representation, while the long immediate
2370 values are printed as hexadecimal.
2371
2372 @option{cpu=...} allows to enforce a particular ISA when disassembling
2373 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2374 This might be useful to select ARC EM or HS ISA, because architecture is same
2375 for those and disassembler relies on private ELF header data to decide if code
2376 is for EM or HS. This option might be specified multiple times - only the
2377 latest value will be used. Valid values are same as for the assembler
2378 @option{-mcpu=...} option.
2379
2380 If the target is an ARM architecture then this switch can be used to
2381 select which register name set is used during disassembler. Specifying
2382 @option{-M reg-names-std} (the default) will select the register names as
2383 used in ARM's instruction set documentation, but with register 13 called
2384 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2385 @option{-M reg-names-apcs} will select the name set used by the ARM
2386 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2387 just use @samp{r} followed by the register number.
2388
2389 There are also two variants on the APCS register naming scheme enabled
2390 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2391 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2392 with the normal register names or the special register names).
2393
2394 This option can also be used for ARM architectures to force the
2395 disassembler to interpret all instructions as Thumb instructions by
2396 using the switch @option{--disassembler-options=force-thumb}. This can be
2397 useful when attempting to disassemble thumb code produced by other
2398 compilers.
2399
2400 For AArch64 targets this switch can be used to set whether instructions are
2401 disassembled as the most general instruction using the @option{-M no-aliases}
2402 option or whether instruction notes should be generated as comments in the
2403 disasssembly using @option{-M notes}.
2404
2405 For the x86, some of the options duplicate functions of the @option{-m}
2406 switch, but allow finer grained control. Multiple selections from the
2407 following may be specified as a comma separated string.
2408 @table @code
2409 @item x86-64
2410 @itemx i386
2411 @itemx i8086
2412 Select disassembly for the given architecture.
2413
2414 @item intel
2415 @itemx att
2416 Select between intel syntax mode and AT&T syntax mode.
2417
2418 @item amd64
2419 @itemx intel64
2420 Select between AMD64 ISA and Intel64 ISA.
2421
2422 @item intel-mnemonic
2423 @itemx att-mnemonic
2424 Select between intel mnemonic mode and AT&T mnemonic mode.
2425 Note: @code{intel-mnemonic} implies @code{intel} and
2426 @code{att-mnemonic} implies @code{att}.
2427
2428 @item addr64
2429 @itemx addr32
2430 @itemx addr16
2431 @itemx data32
2432 @itemx data16
2433 Specify the default address size and operand size. These four options
2434 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2435 appear later in the option string.
2436
2437 @item suffix
2438 When in AT&T mode, instructs the disassembler to print a mnemonic
2439 suffix even when the suffix could be inferred by the operands.
2440 @end table
2441
2442 For PowerPC, the @option{-M} argument @option{raw} selects
2443 disasssembly of hardware insns rather than aliases. For example, you
2444 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2445 rather than @code{li}. All of the @option{-m} arguments for
2446 @command{gas} that select a CPU are supported. These are:
2447 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2448 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2449 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2450 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2451 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2452 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2453 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2454 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2455 @option{power8}, @option{power9}, @option{ppc}, @option{ppc32},
2456 @option{ppc64}, @option{ppc64bridge}, @option{ppcps}, @option{pwr},
2457 @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2458 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2459 @option{pwrx}, @option{titan}, and @option{vle}.
2460 @option{32} and @option{64} modify the default or a prior CPU
2461 selection, disabling and enabling 64-bit insns respectively. In
2462 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2463 and @option{spe} add capabilities to a previous @emph{or later} CPU
2464 selection. @option{any} will disassemble any opcode known to
2465 binutils, but in cases where an opcode has two different meanings or
2466 different arguments, you may not see the disassembly you expect.
2467 If you disassemble without giving a CPU selection, a default will be
2468 chosen from information gleaned by BFD from the object files headers,
2469 but the result again may not be as you expect.
2470
2471 For MIPS, this option controls the printing of instruction mnemonic
2472 names and register names in disassembled instructions. Multiple
2473 selections from the following may be specified as a comma separated
2474 string, and invalid options are ignored:
2475
2476 @table @code
2477 @item no-aliases
2478 Print the 'raw' instruction mnemonic instead of some pseudo
2479 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2480 'sll' instead of 'nop', etc.
2481
2482 @item msa
2483 Disassemble MSA instructions.
2484
2485 @item virt
2486 Disassemble the virtualization ASE instructions.
2487
2488 @item xpa
2489 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2490
2491 @item gpr-names=@var{ABI}
2492 Print GPR (general-purpose register) names as appropriate
2493 for the specified ABI. By default, GPR names are selected according to
2494 the ABI of the binary being disassembled.
2495
2496 @item fpr-names=@var{ABI}
2497 Print FPR (floating-point register) names as
2498 appropriate for the specified ABI. By default, FPR numbers are printed
2499 rather than names.
2500
2501 @item cp0-names=@var{ARCH}
2502 Print CP0 (system control coprocessor; coprocessor 0) register names
2503 as appropriate for the CPU or architecture specified by
2504 @var{ARCH}. By default, CP0 register names are selected according to
2505 the architecture and CPU of the binary being disassembled.
2506
2507 @item hwr-names=@var{ARCH}
2508 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2509 as appropriate for the CPU or architecture specified by
2510 @var{ARCH}. By default, HWR names are selected according to
2511 the architecture and CPU of the binary being disassembled.
2512
2513 @item reg-names=@var{ABI}
2514 Print GPR and FPR names as appropriate for the selected ABI.
2515
2516 @item reg-names=@var{ARCH}
2517 Print CPU-specific register names (CP0 register and HWR names)
2518 as appropriate for the selected CPU or architecture.
2519 @end table
2520
2521 For any of the options listed above, @var{ABI} or
2522 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2523 rather than names, for the selected types of registers.
2524 You can list the available values of @var{ABI} and @var{ARCH} using
2525 the @option{--help} option.
2526
2527 For VAX, you can specify function entry addresses with @option{-M
2528 entry:0xf00ba}. You can use this multiple times to properly
2529 disassemble VAX binary files that don't contain symbol tables (like
2530 ROM dumps). In these cases, the function entry mask would otherwise
2531 be decoded as VAX instructions, which would probably lead the rest
2532 of the function being wrongly disassembled.
2533
2534 @item -p
2535 @itemx --private-headers
2536 Print information that is specific to the object file format. The exact
2537 information printed depends upon the object file format. For some
2538 object file formats, no additional information is printed.
2539
2540 @item -P @var{options}
2541 @itemx --private=@var{options}
2542 Print information that is specific to the object file format. The
2543 argument @var{options} is a comma separated list that depends on the
2544 format (the lists of options is displayed with the help).
2545
2546 For XCOFF, the available options are:
2547 @table @code
2548 @item header
2549 @item aout
2550 @item sections
2551 @item syms
2552 @item relocs
2553 @item lineno,
2554 @item loader
2555 @item except
2556 @item typchk
2557 @item traceback
2558 @item toc
2559 @item ldinfo
2560 @end table
2561
2562 Not all object formats support this option. In particular the ELF
2563 format does not use it.
2564
2565 @item -r
2566 @itemx --reloc
2567 @cindex relocation entries, in object file
2568 Print the relocation entries of the file. If used with @option{-d} or
2569 @option{-D}, the relocations are printed interspersed with the
2570 disassembly.
2571
2572 @item -R
2573 @itemx --dynamic-reloc
2574 @cindex dynamic relocation entries, in object file
2575 Print the dynamic relocation entries of the file. This is only
2576 meaningful for dynamic objects, such as certain types of shared
2577 libraries. As for @option{-r}, if used with @option{-d} or
2578 @option{-D}, the relocations are printed interspersed with the
2579 disassembly.
2580
2581 @item -s
2582 @itemx --full-contents
2583 @cindex sections, full contents
2584 @cindex object file sections
2585 Display the full contents of any sections requested. By default all
2586 non-empty sections are displayed.
2587
2588 @item -S
2589 @itemx --source
2590 @cindex source disassembly
2591 @cindex disassembly, with source
2592 Display source code intermixed with disassembly, if possible. Implies
2593 @option{-d}.
2594
2595 @item --prefix=@var{prefix}
2596 @cindex Add prefix to absolute paths
2597 Specify @var{prefix} to add to the absolute paths when used with
2598 @option{-S}.
2599
2600 @item --prefix-strip=@var{level}
2601 @cindex Strip absolute paths
2602 Indicate how many initial directory names to strip off the hardwired
2603 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2604
2605 @item --show-raw-insn
2606 When disassembling instructions, print the instruction in hex as well as
2607 in symbolic form. This is the default except when
2608 @option{--prefix-addresses} is used.
2609
2610 @item --no-show-raw-insn
2611 When disassembling instructions, do not print the instruction bytes.
2612 This is the default when @option{--prefix-addresses} is used.
2613
2614 @item --insn-width=@var{width}
2615 @cindex Instruction width
2616 Display @var{width} bytes on a single line when disassembling
2617 instructions.
2618
2619 @item -W[lLiaprmfFsoRtUuTgAckK]
2620 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
2621 @include debug.options.texi
2622
2623 @item --dwarf-check
2624 Enable additional checks for consistency of Dwarf information.
2625
2626 @item -G
2627 @itemx --stabs
2628 @cindex stab
2629 @cindex .stab
2630 @cindex debug symbols
2631 @cindex ELF object file format
2632 Display the full contents of any sections requested. Display the
2633 contents of the .stab and .stab.index and .stab.excl sections from an
2634 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2635 @code{.stab} debugging symbol-table entries are carried in an ELF
2636 section. In most other file formats, debugging symbol-table entries are
2637 interleaved with linkage symbols, and are visible in the @option{--syms}
2638 output.
2639
2640 @item --start-address=@var{address}
2641 @cindex start-address
2642 Start displaying data at the specified address. This affects the output
2643 of the @option{-d}, @option{-r} and @option{-s} options.
2644
2645 @item --stop-address=@var{address}
2646 @cindex stop-address
2647 Stop displaying data at the specified address. This affects the output
2648 of the @option{-d}, @option{-r} and @option{-s} options.
2649
2650 @item -t
2651 @itemx --syms
2652 @cindex symbol table entries, printing
2653 Print the symbol table entries of the file.
2654 This is similar to the information provided by the @samp{nm} program,
2655 although the display format is different. The format of the output
2656 depends upon the format of the file being dumped, but there are two main
2657 types. One looks like this:
2658
2659 @smallexample
2660 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2661 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2662 @end smallexample
2663
2664 where the number inside the square brackets is the number of the entry
2665 in the symbol table, the @var{sec} number is the section number, the
2666 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2667 symbol's type, the @var{scl} number is the symbol's storage class and
2668 the @var{nx} value is the number of auxilary entries associated with
2669 the symbol. The last two fields are the symbol's value and its name.
2670
2671 The other common output format, usually seen with ELF based files,
2672 looks like this:
2673
2674 @smallexample
2675 00000000 l d .bss 00000000 .bss
2676 00000000 g .text 00000000 fred
2677 @end smallexample
2678
2679 Here the first number is the symbol's value (sometimes refered to as
2680 its address). The next field is actually a set of characters and
2681 spaces indicating the flag bits that are set on the symbol. These
2682 characters are described below. Next is the section with which the
2683 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2684 not connected with any section), or @emph{*UND*} if the section is
2685 referenced in the file being dumped, but not defined there.
2686
2687 After the section name comes another field, a number, which for common
2688 symbols is the alignment and for other symbol is the size. Finally
2689 the symbol's name is displayed.
2690
2691 The flag characters are divided into 7 groups as follows:
2692 @table @code
2693 @item l
2694 @itemx g
2695 @itemx u
2696 @itemx !
2697 The symbol is a local (l), global (g), unique global (u), neither
2698 global nor local (a space) or both global and local (!). A
2699 symbol can be neither local or global for a variety of reasons, e.g.,
2700 because it is used for debugging, but it is probably an indication of
2701 a bug if it is ever both local and global. Unique global symbols are
2702 a GNU extension to the standard set of ELF symbol bindings. For such
2703 a symbol the dynamic linker will make sure that in the entire process
2704 there is just one symbol with this name and type in use.
2705
2706 @item w
2707 The symbol is weak (w) or strong (a space).
2708
2709 @item C
2710 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2711
2712 @item W
2713 The symbol is a warning (W) or a normal symbol (a space). A warning
2714 symbol's name is a message to be displayed if the symbol following the
2715 warning symbol is ever referenced.
2716
2717 @item I
2718 @item i
2719 The symbol is an indirect reference to another symbol (I), a function
2720 to be evaluated during reloc processing (i) or a normal symbol (a
2721 space).
2722
2723 @item d
2724 @itemx D
2725 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2726 normal symbol (a space).
2727
2728 @item F
2729 @item f
2730 @item O
2731 The symbol is the name of a function (F) or a file (f) or an object
2732 (O) or just a normal symbol (a space).
2733 @end table
2734
2735 @item -T
2736 @itemx --dynamic-syms
2737 @cindex dynamic symbol table entries, printing
2738 Print the dynamic symbol table entries of the file. This is only
2739 meaningful for dynamic objects, such as certain types of shared
2740 libraries. This is similar to the information provided by the @samp{nm}
2741 program when given the @option{-D} (@option{--dynamic}) option.
2742
2743 The output format is similar to that produced by the @option{--syms}
2744 option, except that an extra field is inserted before the symbol's
2745 name, giving the version information associated with the symbol.
2746 If the version is the default version to be used when resolving
2747 unversioned references to the symbol then it's displayed as is,
2748 otherwise it's put into parentheses.
2749
2750 @item --special-syms
2751 When displaying symbols include those which the target considers to be
2752 special in some way and which would not normally be of interest to the
2753 user.
2754
2755 @item -V
2756 @itemx --version
2757 Print the version number of @command{objdump} and exit.
2758
2759 @item -x
2760 @itemx --all-headers
2761 @cindex all header information, object file
2762 @cindex header information, all
2763 Display all available header information, including the symbol table and
2764 relocation entries. Using @option{-x} is equivalent to specifying all of
2765 @option{-a -f -h -p -r -t}.
2766
2767 @item -w
2768 @itemx --wide
2769 @cindex wide output, printing
2770 Format some lines for output devices that have more than 80 columns.
2771 Also do not truncate symbol names when they are displayed.
2772
2773 @item -z
2774 @itemx --disassemble-zeroes
2775 Normally the disassembly output will skip blocks of zeroes. This
2776 option directs the disassembler to disassemble those blocks, just like
2777 any other data.
2778 @end table
2779
2780 @c man end
2781
2782 @ignore
2783 @c man begin SEEALSO objdump
2784 nm(1), readelf(1), and the Info entries for @file{binutils}.
2785 @c man end
2786 @end ignore
2787
2788 @node ranlib
2789 @chapter ranlib
2790
2791 @kindex ranlib
2792 @cindex archive contents
2793 @cindex symbol index
2794
2795 @c man title ranlib generate index to archive.
2796
2797 @smallexample
2798 @c man begin SYNOPSIS ranlib
2799 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2800 @c man end
2801 @end smallexample
2802
2803 @c man begin DESCRIPTION ranlib
2804
2805 @command{ranlib} generates an index to the contents of an archive and
2806 stores it in the archive. The index lists each symbol defined by a
2807 member of an archive that is a relocatable object file.
2808
2809 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2810
2811 An archive with such an index speeds up linking to the library and
2812 allows routines in the library to call each other without regard to
2813 their placement in the archive.
2814
2815 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2816 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2817 @xref{ar}.
2818
2819 @c man end
2820
2821 @c man begin OPTIONS ranlib
2822
2823 @table @env
2824 @item -h
2825 @itemx -H
2826 @itemx --help
2827 Show usage information for @command{ranlib}.
2828
2829 @item -v
2830 @itemx -V
2831 @itemx --version
2832 Show the version number of @command{ranlib}.
2833
2834 @item -D
2835 @cindex deterministic archives
2836 @kindex --enable-deterministic-archives
2837 Operate in @emph{deterministic} mode. The symbol map archive member's
2838 header will show zero for the UID, GID, and timestamp. When this
2839 option is used, multiple runs will produce identical output files.
2840
2841 If @file{binutils} was configured with
2842 @option{--enable-deterministic-archives}, then this mode is on by
2843 default. It can be disabled with the @samp{-U} option, described
2844 below.
2845
2846 @item -t
2847 Update the timestamp of the symbol map of an archive.
2848
2849 @item -U
2850 @cindex deterministic archives
2851 @kindex --enable-deterministic-archives
2852 Do @emph{not} operate in @emph{deterministic} mode. This is the
2853 inverse of the @samp{-D} option, above: the archive index will get
2854 actual UID, GID, timestamp, and file mode values.
2855
2856 If @file{binutils} was configured @emph{without}
2857 @option{--enable-deterministic-archives}, then this mode is on by
2858 default.
2859
2860 @end table
2861
2862 @c man end
2863
2864 @ignore
2865 @c man begin SEEALSO ranlib
2866 ar(1), nm(1), and the Info entries for @file{binutils}.
2867 @c man end
2868 @end ignore
2869
2870 @node size
2871 @chapter size
2872
2873 @kindex size
2874 @cindex section sizes
2875
2876 @c man title size list section sizes and total size.
2877
2878 @smallexample
2879 @c man begin SYNOPSIS size
2880 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
2881 [@option{--help}]
2882 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2883 [@option{--common}]
2884 [@option{-t}|@option{--totals}]
2885 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2886 [@var{objfile}@dots{}]
2887 @c man end
2888 @end smallexample
2889
2890 @c man begin DESCRIPTION size
2891
2892 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2893 size---for each of the object or archive files @var{objfile} in its
2894 argument list. By default, one line of output is generated for each
2895 object file or each module in an archive.
2896
2897 @var{objfile}@dots{} are the object files to be examined.
2898 If none are specified, the file @code{a.out} will be used.
2899
2900 @c man end
2901
2902 @c man begin OPTIONS size
2903
2904 The command-line options have the following meanings:
2905
2906 @table @env
2907 @item -A
2908 @itemx -B
2909 @itemx -G
2910 @itemx --format=@var{compatibility}
2911 @cindex @command{size} display format
2912 Using one of these options, you can choose whether the output from @sc{gnu}
2913 @command{size} resembles output from System V @command{size} (using @option{-A},
2914 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2915 @option{--format=berkeley}). The default is the one-line format similar to
2916 Berkeley's. Alternatively, you can choose the GNU format output
2917 (using @option{-G}, or @option{--format=gnu}), this is similar to
2918 Berkeley's output format, but sizes are counted differently.
2919 @c Bonus for doc-source readers: you can also say --format=strange (or
2920 @c anything else that starts with 's') for sysv, and --format=boring (or
2921 @c anything else that starts with 'b') for Berkeley.
2922
2923 Here is an example of the Berkeley (default) format of output from
2924 @command{size}:
2925 @smallexample
2926 $ size --format=Berkeley ranlib size
2927 text data bss dec hex filename
2928 294880 81920 11592 388392 5ed28 ranlib
2929 294880 81920 11888 388688 5ee50 size
2930 @end smallexample
2931
2932 The Berkeley style output counts read only data in the @code{text}
2933 column, not in the @code{data} column, the @code{dec} and @code{hex}
2934 columns both display the sum of the @code{text}, @code{data}, and
2935 @code{bss} columns in decimal and hexadecimal respectively.
2936
2937 The GNU format counts read only data in the @code{data} column, not
2938 the @code{text} column, and only displays the sum of the @code{text},
2939 @code{data}, and @code{bss} columns once, in the @code{total} column.
2940 The @option{--radix} option can be used to change the number base for
2941 all columns. Here is the same data displayed with GNU conventions:
2942
2943 @smallexample
2944 $ size --format=GNU ranlib size
2945 text data bss total filename
2946 279880 96920 11592 388392 ranlib
2947 279880 96920 11888 388688 size
2948 @end smallexample
2949
2950 @noindent
2951 This is the same data, but displayed closer to System V conventions:
2952
2953 @smallexample
2954 $ size --format=SysV ranlib size
2955 ranlib :
2956 section size addr
2957 .text 294880 8192
2958 .data 81920 303104
2959 .bss 11592 385024
2960 Total 388392
2961
2962
2963 size :
2964 section size addr
2965 .text 294880 8192
2966 .data 81920 303104
2967 .bss 11888 385024
2968 Total 388688
2969 @end smallexample
2970
2971 @item --help
2972 Show a summary of acceptable arguments and options.
2973
2974 @item -d
2975 @itemx -o
2976 @itemx -x
2977 @itemx --radix=@var{number}
2978 @cindex @command{size} number format
2979 @cindex radix for section sizes
2980 Using one of these options, you can control whether the size of each
2981 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2982 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2983 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2984 values (8, 10, 16) are supported. The total size is always given in two
2985 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2986 octal and hexadecimal if you're using @option{-o}.
2987
2988 @item --common
2989 Print total size of common symbols in each file. When using Berkeley
2990 or GNU format these are included in the bss size.
2991
2992 @item -t
2993 @itemx --totals
2994 Show totals of all objects listed (Berkeley or GNU format mode only).
2995
2996 @item --target=@var{bfdname}
2997 @cindex object code format
2998 Specify that the object-code format for @var{objfile} is
2999 @var{bfdname}. This option may not be necessary; @command{size} can
3000 automatically recognize many formats.
3001 @xref{Target Selection}, for more information.
3002
3003 @item -V
3004 @itemx --version
3005 Display the version number of @command{size}.
3006 @end table
3007
3008 @c man end
3009
3010 @ignore
3011 @c man begin SEEALSO size
3012 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3013 @c man end
3014 @end ignore
3015
3016 @node strings
3017 @chapter strings
3018 @kindex strings
3019 @cindex listings strings
3020 @cindex printing strings
3021 @cindex strings, printing
3022
3023 @c man title strings print the strings of printable characters in files.
3024
3025 @smallexample
3026 @c man begin SYNOPSIS strings
3027 strings [@option{-afovV}] [@option{-}@var{min-len}]
3028 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3029 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3030 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3031 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3032 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3033 [@option{-w}] [@option{--include-all-whitespace}]
3034 [@option{-s}] [@option{--output-separator}@var{sep_string}]
3035 [@option{--help}] [@option{--version}] @var{file}@dots{}
3036 @c man end
3037 @end smallexample
3038
3039 @c man begin DESCRIPTION strings
3040
3041 For each @var{file} given, @sc{gnu} @command{strings} prints the
3042 printable character sequences that are at least 4 characters long (or
3043 the number given with the options below) and are followed by an
3044 unprintable character.
3045
3046 Depending upon how the strings program was configured it will default
3047 to either displaying all the printable sequences that it can find in
3048 each file, or only those sequences that are in loadable, initialized
3049 data sections. If the file type in unrecognizable, or if strings is
3050 reading from stdin then it will always display all of the printable
3051 sequences that it can find.
3052
3053 For backwards compatibility any file that occurs after a command-line
3054 option of just @option{-} will also be scanned in full, regardless of
3055 the presence of any @option{-d} option.
3056
3057 @command{strings} is mainly useful for determining the contents of
3058 non-text files.
3059
3060 @c man end
3061
3062 @c man begin OPTIONS strings
3063
3064 @table @env
3065 @item -a
3066 @itemx --all
3067 @itemx -
3068 Scan the whole file, regardless of what sections it contains or
3069 whether those sections are loaded or initialized. Normally this is
3070 the default behaviour, but strings can be configured so that the
3071 @option{-d} is the default instead.
3072
3073 The @option{-} option is position dependent and forces strings to
3074 perform full scans of any file that is mentioned after the @option{-}
3075 on the command line, even if the @option{-d} option has been
3076 specified.
3077
3078 @item -d
3079 @itemx --data
3080 Only print strings from initialized, loaded data sections in the
3081 file. This may reduce the amount of garbage in the output, but it
3082 also exposes the strings program to any security flaws that may be
3083 present in the BFD library used to scan and load sections. Strings
3084 can be configured so that this option is the default behaviour. In
3085 such cases the @option{-a} option can be used to avoid using the BFD
3086 library and instead just print all of the strings found in the file.
3087
3088 @item -f
3089 @itemx --print-file-name
3090 Print the name of the file before each string.
3091
3092 @item --help
3093 Print a summary of the program usage on the standard output and exit.
3094
3095 @item -@var{min-len}
3096 @itemx -n @var{min-len}
3097 @itemx --bytes=@var{min-len}
3098 Print sequences of characters that are at least @var{min-len} characters
3099 long, instead of the default 4.
3100
3101 @item -o
3102 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3103 act like @samp{-t d} instead. Since we can not be compatible with both
3104 ways, we simply chose one.
3105
3106 @item -t @var{radix}
3107 @itemx --radix=@var{radix}
3108 Print the offset within the file before each string. The single
3109 character argument specifies the radix of the offset---@samp{o} for
3110 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3111
3112 @item -e @var{encoding}
3113 @itemx --encoding=@var{encoding}
3114 Select the character encoding of the strings that are to be found.
3115 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3116 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3117 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3118 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3119 littleendian. Useful for finding wide character strings. (@samp{l}
3120 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3121
3122 @item -T @var{bfdname}
3123 @itemx --target=@var{bfdname}
3124 @cindex object code format
3125 Specify an object code format other than your system's default format.
3126 @xref{Target Selection}, for more information.
3127
3128 @item -v
3129 @itemx -V
3130 @itemx --version
3131 Print the program version number on the standard output and exit.
3132
3133 @item -w
3134 @itemx --include-all-whitespace
3135 By default tab and space characters are included in the strings that
3136 are displayed, but other whitespace characters, such a newlines and
3137 carriage returns, are not. The @option{-w} option changes this so
3138 that all whitespace characters are considered to be part of a string.
3139
3140 @item -s
3141 @itemx --output-separator
3142 By default, output strings are delimited by a new-line. This option
3143 allows you to supply any string to be used as the output record
3144 separator. Useful with --include-all-whitespace where strings
3145 may contain new-lines internally.
3146 @end table
3147
3148 @c man end
3149
3150 @ignore
3151 @c man begin SEEALSO strings
3152 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3153 and the Info entries for @file{binutils}.
3154 @c man end
3155 @end ignore
3156
3157 @node strip
3158 @chapter strip
3159
3160 @kindex strip
3161 @cindex removing symbols
3162 @cindex discarding symbols
3163 @cindex symbols, discarding
3164
3165 @c man title strip Discard symbols from object files.
3166
3167 @smallexample
3168 @c man begin SYNOPSIS strip
3169 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3170 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3171 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3172 [@option{-s}|@option{--strip-all}]
3173 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3174 [@option{--strip-dwo}]
3175 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3176 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3177 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3178 [@option{-w}|@option{--wildcard}]
3179 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3180 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3181 [@option{--remove-relocations=}@var{sectionpattern}]
3182 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3183 [@option{-D}|@option{--enable-deterministic-archives}]
3184 [@option{-U}|@option{--disable-deterministic-archives}]
3185 [@option{--keep-file-symbols}]
3186 [@option{--only-keep-debug}]
3187 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3188 [@option{--help}] [@option{--info}]
3189 @var{objfile}@dots{}
3190 @c man end
3191 @end smallexample
3192
3193 @c man begin DESCRIPTION strip
3194
3195 @sc{gnu} @command{strip} discards all symbols from object files
3196 @var{objfile}. The list of object files may include archives.
3197 At least one object file must be given.
3198
3199 @command{strip} modifies the files named in its argument,
3200 rather than writing modified copies under different names.
3201
3202 @c man end
3203
3204 @c man begin OPTIONS strip
3205
3206 @table @env
3207 @item -F @var{bfdname}
3208 @itemx --target=@var{bfdname}
3209 Treat the original @var{objfile} as a file with the object
3210 code format @var{bfdname}, and rewrite it in the same format.
3211 @xref{Target Selection}, for more information.
3212
3213 @item --help
3214 Show a summary of the options to @command{strip} and exit.
3215
3216 @item --info
3217 Display a list showing all architectures and object formats available.
3218
3219 @item -I @var{bfdname}
3220 @itemx --input-target=@var{bfdname}
3221 Treat the original @var{objfile} as a file with the object
3222 code format @var{bfdname}.
3223 @xref{Target Selection}, for more information.
3224
3225 @item -O @var{bfdname}
3226 @itemx --output-target=@var{bfdname}
3227 Replace @var{objfile} with a file in the output format @var{bfdname}.
3228 @xref{Target Selection}, for more information.
3229
3230 @item -R @var{sectionname}
3231 @itemx --remove-section=@var{sectionname}
3232 Remove any section named @var{sectionname} from the output file, in
3233 addition to whatever sections would otherwise be removed. This
3234 option may be given more than once. Note that using this option
3235 inappropriately may make the output file unusable. The wildcard
3236 character @samp{*} may be given at the end of @var{sectionname}. If
3237 so, then any section starting with @var{sectionname} will be removed.
3238
3239 If the first character of @var{sectionpattern} is the exclamation
3240 point (!) then matching sections will not be removed even if an
3241 earlier use of @option{--remove-section} on the same command line
3242 would otherwise remove it. For example:
3243
3244 @smallexample
3245 --remove-section=.text.* --remove-section=!.text.foo
3246 @end smallexample
3247
3248 will remove all sections matching the pattern '.text.*', but will not
3249 remove the section '.text.foo'.
3250
3251 @item --remove-relocations=@var{sectionpattern}
3252 Remove relocations from the output file for any section matching
3253 @var{sectionpattern}. This option may be given more than once. Note
3254 that using this option inappropriately may make the output file
3255 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3256 For example:
3257
3258 @smallexample
3259 --remove-relocations=.text.*
3260 @end smallexample
3261
3262 will remove the relocations for all sections matching the patter
3263 '.text.*'.
3264
3265 If the first character of @var{sectionpattern} is the exclamation
3266 point (!) then matching sections will not have their relocation
3267 removed even if an earlier use of @option{--remove-relocations} on the
3268 same command line would otherwise cause the relocations to be removed.
3269 For example:
3270
3271 @smallexample
3272 --remove-relocations=.text.* --remove-relocations=!.text.foo
3273 @end smallexample
3274
3275 will remove all relocations for sections matching the pattern
3276 '.text.*', but will not remove relocations for the section
3277 '.text.foo'.
3278
3279 @item -s
3280 @itemx --strip-all
3281 Remove all symbols.
3282
3283 @item -g
3284 @itemx -S
3285 @itemx -d
3286 @itemx --strip-debug
3287 Remove debugging symbols only.
3288
3289 @item --strip-dwo
3290 Remove the contents of all DWARF .dwo sections, leaving the
3291 remaining debugging sections and all symbols intact.
3292 See the description of this option in the @command{objcopy} section
3293 for more information.
3294
3295 @item --strip-unneeded
3296 Remove all symbols that are not needed for relocation processing.
3297
3298 @item -K @var{symbolname}
3299 @itemx --keep-symbol=@var{symbolname}
3300 When stripping symbols, keep symbol @var{symbolname} even if it would
3301 normally be stripped. This option may be given more than once.
3302
3303 @item -M
3304 @itemx --merge-notes
3305 @itemx --no-merge-notes
3306 For ELF files, attempt (or do not attempt) to reduce the size of any
3307 SHT_NOTE type sections by removing duplicate notes. The default is to
3308 attempt this reduction.
3309
3310 @item -N @var{symbolname}
3311 @itemx --strip-symbol=@var{symbolname}
3312 Remove symbol @var{symbolname} from the source file. This option may be
3313 given more than once, and may be combined with strip options other than
3314 @option{-K}.
3315
3316 @item -o @var{file}
3317 Put the stripped output in @var{file}, rather than replacing the
3318 existing file. When this argument is used, only one @var{objfile}
3319 argument may be specified.
3320
3321 @item -p
3322 @itemx --preserve-dates
3323 Preserve the access and modification dates of the file.
3324
3325 @item -D
3326 @itemx --enable-deterministic-archives
3327 @cindex deterministic archives
3328 @kindex --enable-deterministic-archives
3329 Operate in @emph{deterministic} mode. When copying archive members
3330 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3331 and use consistent file modes for all files.
3332
3333 If @file{binutils} was configured with
3334 @option{--enable-deterministic-archives}, then this mode is on by default.
3335 It can be disabled with the @samp{-U} option, below.
3336
3337 @item -U
3338 @itemx --disable-deterministic-archives
3339 @cindex deterministic archives
3340 @kindex --enable-deterministic-archives
3341 Do @emph{not} operate in @emph{deterministic} mode. This is the
3342 inverse of the @option{-D} option, above: when copying archive members
3343 and writing the archive index, use their actual UID, GID, timestamp,
3344 and file mode values.
3345
3346 This is the default unless @file{binutils} was configured with
3347 @option{--enable-deterministic-archives}.
3348
3349 @item -w
3350 @itemx --wildcard
3351 Permit regular expressions in @var{symbolname}s used in other command
3352 line options. The question mark (?), asterisk (*), backslash (\) and
3353 square brackets ([]) operators can be used anywhere in the symbol
3354 name. If the first character of the symbol name is the exclamation
3355 point (!) then the sense of the switch is reversed for that symbol.
3356 For example:
3357
3358 @smallexample
3359 -w -K !foo -K fo*
3360 @end smallexample
3361
3362 would cause strip to only keep symbols that start with the letters
3363 ``fo'', but to discard the symbol ``foo''.
3364
3365 @item -x
3366 @itemx --discard-all
3367 Remove non-global symbols.
3368
3369 @item -X
3370 @itemx --discard-locals
3371 Remove compiler-generated local symbols.
3372 (These usually start with @samp{L} or @samp{.}.)
3373
3374 @item --keep-file-symbols
3375 When stripping a file, perhaps with @option{--strip-debug} or
3376 @option{--strip-unneeded}, retain any symbols specifying source file names,
3377 which would otherwise get stripped.
3378
3379 @item --only-keep-debug
3380 Strip a file, emptying the contents of any sections that would not be
3381 stripped by @option{--strip-debug} and leaving the debugging sections
3382 intact. In ELF files, this preserves all the note sections in the
3383 output as well.
3384
3385 Note - the section headers of the stripped sections are preserved,
3386 including their sizes, but the contents of the section are discarded.
3387 The section headers are preserved so that other tools can match up the
3388 debuginfo file with the real executable, even if that executable has
3389 been relocated to a different address space.
3390
3391 The intention is that this option will be used in conjunction with
3392 @option{--add-gnu-debuglink} to create a two part executable. One a
3393 stripped binary which will occupy less space in RAM and in a
3394 distribution and the second a debugging information file which is only
3395 needed if debugging abilities are required. The suggested procedure
3396 to create these files is as follows:
3397
3398 @enumerate
3399 @item Link the executable as normal. Assuming that it is called
3400 @code{foo} then...
3401 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3402 create a file containing the debugging info.
3403 @item Run @code{objcopy --strip-debug foo} to create a
3404 stripped executable.
3405 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3406 to add a link to the debugging info into the stripped executable.
3407 @end enumerate
3408
3409 Note---the choice of @code{.dbg} as an extension for the debug info
3410 file is arbitrary. Also the @code{--only-keep-debug} step is
3411 optional. You could instead do this:
3412
3413 @enumerate
3414 @item Link the executable as normal.
3415 @item Copy @code{foo} to @code{foo.full}
3416 @item Run @code{strip --strip-debug foo}
3417 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3418 @end enumerate
3419
3420 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3421 full executable. It does not have to be a file created by the
3422 @option{--only-keep-debug} switch.
3423
3424 Note---this switch is only intended for use on fully linked files. It
3425 does not make sense to use it on object files where the debugging
3426 information may be incomplete. Besides the gnu_debuglink feature
3427 currently only supports the presence of one filename containing
3428 debugging information, not multiple filenames on a one-per-object-file
3429 basis.
3430
3431 @item -V
3432 @itemx --version
3433 Show the version number for @command{strip}.
3434
3435 @item -v
3436 @itemx --verbose
3437 Verbose output: list all object files modified. In the case of
3438 archives, @samp{strip -v} lists all members of the archive.
3439 @end table
3440
3441 @c man end
3442
3443 @ignore
3444 @c man begin SEEALSO strip
3445 the Info entries for @file{binutils}.
3446 @c man end
3447 @end ignore
3448
3449 @node c++filt, addr2line, strip, Top
3450 @chapter c++filt
3451
3452 @kindex c++filt
3453 @cindex demangling C++ symbols
3454
3455 @c man title cxxfilt Demangle C++ and Java symbols.
3456
3457 @smallexample
3458 @c man begin SYNOPSIS cxxfilt
3459 c++filt [@option{-_}|@option{--strip-underscore}]
3460 [@option{-n}|@option{--no-strip-underscore}]
3461 [@option{-p}|@option{--no-params}]
3462 [@option{-t}|@option{--types}]
3463 [@option{-i}|@option{--no-verbose}]
3464 [@option{-r}|@option{--no-recurse-limit}]
3465 [@option{-R}|@option{--recurse-limit}]
3466 [@option{-s} @var{format}|@option{--format=}@var{format}]
3467 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3468 @c man end
3469 @end smallexample
3470
3471 @c man begin DESCRIPTION cxxfilt
3472
3473 @kindex cxxfilt
3474 The C++ and Java languages provide function overloading, which means
3475 that you can write many functions with the same name, providing that
3476 each function takes parameters of different types. In order to be
3477 able to distinguish these similarly named functions C++ and Java
3478 encode them into a low-level assembler name which uniquely identifies
3479 each different version. This process is known as @dfn{mangling}. The
3480 @command{c++filt}
3481 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3482 MS-DOS this program is named @command{CXXFILT}.}
3483 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3484 names into user-level names so that they can be read.
3485
3486 Every alphanumeric word (consisting of letters, digits, underscores,
3487 dollars, or periods) seen in the input is a potential mangled name.
3488 If the name decodes into a C++ name, the C++ name replaces the
3489 low-level name in the output, otherwise the original word is output.
3490 In this way you can pass an entire assembler source file, containing
3491 mangled names, through @command{c++filt} and see the same source file
3492 containing demangled names.
3493
3494 You can also use @command{c++filt} to decipher individual symbols by
3495 passing them on the command line:
3496
3497 @example
3498 c++filt @var{symbol}
3499 @end example
3500
3501 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3502 names from the standard input instead. All the results are printed on
3503 the standard output. The difference between reading names from the
3504 command line versus reading names from the standard input is that
3505 command-line arguments are expected to be just mangled names and no
3506 checking is performed to separate them from surrounding text. Thus
3507 for example:
3508
3509 @smallexample
3510 c++filt -n _Z1fv
3511 @end smallexample
3512
3513 will work and demangle the name to ``f()'' whereas:
3514
3515 @smallexample
3516 c++filt -n _Z1fv,
3517 @end smallexample
3518
3519 will not work. (Note the extra comma at the end of the mangled
3520 name which makes it invalid). This command however will work:
3521
3522 @smallexample
3523 echo _Z1fv, | c++filt -n
3524 @end smallexample
3525
3526 and will display ``f(),'', i.e., the demangled name followed by a
3527 trailing comma. This behaviour is because when the names are read
3528 from the standard input it is expected that they might be part of an
3529 assembler source file where there might be extra, extraneous
3530 characters trailing after a mangled name. For example:
3531
3532 @smallexample
3533 .type _Z1fv, @@function
3534 @end smallexample
3535
3536 @c man end
3537
3538 @c man begin OPTIONS cxxfilt
3539
3540 @table @env
3541 @item -_
3542 @itemx --strip-underscore
3543 On some systems, both the C and C++ compilers put an underscore in front
3544 of every name. For example, the C name @code{foo} gets the low-level
3545 name @code{_foo}. This option removes the initial underscore. Whether
3546 @command{c++filt} removes the underscore by default is target dependent.
3547
3548 @item -n
3549 @itemx --no-strip-underscore
3550 Do not remove the initial underscore.
3551
3552 @item -p
3553 @itemx --no-params
3554 When demangling the name of a function, do not display the types of
3555 the function's parameters.
3556
3557 @item -t
3558 @itemx --types
3559 Attempt to demangle types as well as function names. This is disabled
3560 by default since mangled types are normally only used internally in
3561 the compiler, and they can be confused with non-mangled names. For example,
3562 a function called ``a'' treated as a mangled type name would be
3563 demangled to ``signed char''.
3564
3565 @item -i
3566 @itemx --no-verbose
3567 Do not include implementation details (if any) in the demangled
3568 output.
3569
3570 @item -r
3571 @itemx -R
3572 @itemx --recurse-limit
3573 @itemx --no-recurse-limit
3574 @itemx --recursion-limit
3575 @itemx --no-recursion-limit
3576 Enables or disables a limit on the amount of recursion performed
3577 whilst demangling strings. Since the name mangling formats allow for
3578 an inifinite level of recursion it is possible to create strings whose
3579 decoding will exhaust the amount of stack space available on the host
3580 machine, triggering a memory fault. The limit tries to prevent this
3581 from happening by restricting recursion to 2048 levels of nesting.
3582
3583 The default is for this limit to be enabled, but disabling it may be
3584 necessary in order to demangle truly complicated names. Note however
3585 that if the recursion limit is disabled then stack exhaustion is
3586 possible and any bug reports about such an event will be rejected.
3587
3588 The @option{-r} option is a synonym for the
3589 @option{--no-recurse-limit} option. The @option{-R} option is a
3590 synonym for the @option{--recurse-limit} option.
3591
3592 @item -s @var{format}
3593 @itemx --format=@var{format}
3594 @command{c++filt} can decode various methods of mangling, used by
3595 different compilers. The argument to this option selects which
3596 method it uses:
3597
3598 @table @code
3599 @item auto
3600 Automatic selection based on executable (the default method)
3601 @item gnu
3602 the one used by the @sc{gnu} C++ compiler (g++)
3603 @item lucid
3604 the one used by the Lucid compiler (lcc)
3605 @item arm
3606 the one specified by the C++ Annotated Reference Manual
3607 @item hp
3608 the one used by the HP compiler (aCC)
3609 @item edg
3610 the one used by the EDG compiler
3611 @item gnu-v3
3612 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3613 @item java
3614 the one used by the @sc{gnu} Java compiler (gcj)
3615 @item gnat
3616 the one used by the @sc{gnu} Ada compiler (GNAT).
3617 @end table
3618
3619 @item --help
3620 Print a summary of the options to @command{c++filt} and exit.
3621
3622 @item --version
3623 Print the version number of @command{c++filt} and exit.
3624 @end table
3625
3626 @c man end
3627
3628 @ignore
3629 @c man begin SEEALSO cxxfilt
3630 the Info entries for @file{binutils}.
3631 @c man end
3632 @end ignore
3633
3634 @quotation
3635 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3636 user interface are subject to change in future releases. In particular,
3637 a command-line option may be required in the future to decode a name
3638 passed as an argument on the command line; in other words,
3639
3640 @example
3641 c++filt @var{symbol}
3642 @end example
3643
3644 @noindent
3645 may in a future release become
3646
3647 @example
3648 c++filt @var{option} @var{symbol}
3649 @end example
3650 @end quotation
3651
3652 @node addr2line
3653 @chapter addr2line
3654
3655 @kindex addr2line
3656 @cindex address to file name and line number
3657
3658 @c man title addr2line convert addresses into file names and line numbers.
3659
3660 @smallexample
3661 @c man begin SYNOPSIS addr2line
3662 addr2line [@option{-a}|@option{--addresses}]
3663 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3664 [@option{-C}|@option{--demangle}[=@var{style}]]
3665 [@option{-r}|@option{--no-recurse-limit}]
3666 [@option{-R}|@option{--recurse-limit}]
3667 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3668 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3669 [@option{-i}|@option{--inlines}]
3670 [@option{-p}|@option{--pretty-print}]
3671 [@option{-j}|@option{--section=}@var{name}]
3672 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3673 [addr addr @dots{}]
3674 @c man end
3675 @end smallexample
3676
3677 @c man begin DESCRIPTION addr2line
3678
3679 @command{addr2line} translates addresses into file names and line numbers.
3680 Given an address in an executable or an offset in a section of a relocatable
3681 object, it uses the debugging information to figure out which file name and
3682 line number are associated with it.
3683
3684 The executable or relocatable object to use is specified with the @option{-e}
3685 option. The default is the file @file{a.out}. The section in the relocatable
3686 object to use is specified with the @option{-j} option.
3687
3688 @command{addr2line} has two modes of operation.
3689
3690 In the first, hexadecimal addresses are specified on the command line,
3691 and @command{addr2line} displays the file name and line number for each
3692 address.
3693
3694 In the second, @command{addr2line} reads hexadecimal addresses from
3695 standard input, and prints the file name and line number for each
3696 address on standard output. In this mode, @command{addr2line} may be used
3697 in a pipe to convert dynamically chosen addresses.
3698
3699 The format of the output is @samp{FILENAME:LINENO}. By default
3700 each input address generates one line of output.
3701
3702 Two options can generate additional lines before each
3703 @samp{FILENAME:LINENO} line (in that order).
3704
3705 If the @option{-a} option is used then a line with the input address
3706 is displayed.
3707
3708 If the @option{-f} option is used, then a line with the
3709 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3710 containing the address.
3711
3712 One option can generate additional lines after the
3713 @samp{FILENAME:LINENO} line.
3714
3715 If the @option{-i} option is used and the code at the given address is
3716 present there because of inlining by the compiler then additional
3717 lines are displayed afterwards. One or two extra lines (if the
3718 @option{-f} option is used) are displayed for each inlined function.
3719
3720 Alternatively if the @option{-p} option is used then each input
3721 address generates a single, long, output line containing the address,
3722 the function name, the file name and the line number. If the
3723 @option{-i} option has also been used then any inlined functions will
3724 be displayed in the same manner, but on separate lines, and prefixed
3725 by the text @samp{(inlined by)}.
3726
3727 If the file name or function name can not be determined,
3728 @command{addr2line} will print two question marks in their place. If the
3729 line number can not be determined, @command{addr2line} will print 0.
3730
3731 @c man end
3732
3733 @c man begin OPTIONS addr2line
3734
3735 The long and short forms of options, shown here as alternatives, are
3736 equivalent.
3737
3738 @table @env
3739 @item -a
3740 @itemx --addresses
3741 Display the address before the function name, file and line number
3742 information. The address is printed with a @samp{0x} prefix to easily
3743 identify it.
3744
3745 @item -b @var{bfdname}
3746 @itemx --target=@var{bfdname}
3747 @cindex object code format
3748 Specify that the object-code format for the object files is
3749 @var{bfdname}.
3750
3751 @item -C
3752 @itemx --demangle[=@var{style}]
3753 @cindex demangling in objdump
3754 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3755 Besides removing any initial underscore prepended by the system, this
3756 makes C++ function names readable. Different compilers have different
3757 mangling styles. The optional demangling style argument can be used to
3758 choose an appropriate demangling style for your compiler. @xref{c++filt},
3759 for more information on demangling.
3760
3761 @item -e @var{filename}
3762 @itemx --exe=@var{filename}
3763 Specify the name of the executable for which addresses should be
3764 translated. The default file is @file{a.out}.
3765
3766 @item -f
3767 @itemx --functions
3768 Display function names as well as file and line number information.
3769
3770 @item -s
3771 @itemx --basenames
3772 Display only the base of each file name.
3773
3774 @item -i
3775 @itemx --inlines
3776 If the address belongs to a function that was inlined, the source
3777 information for all enclosing scopes back to the first non-inlined
3778 function will also be printed. For example, if @code{main} inlines
3779 @code{callee1} which inlines @code{callee2}, and address is from
3780 @code{callee2}, the source information for @code{callee1} and @code{main}
3781 will also be printed.
3782
3783 @item -j
3784 @itemx --section
3785 Read offsets relative to the specified section instead of absolute addresses.
3786
3787 @item -p
3788 @itemx --pretty-print
3789 Make the output more human friendly: each location are printed on one line.
3790 If option @option{-i} is specified, lines for all enclosing scopes are
3791 prefixed with @samp{(inlined by)}.
3792
3793 @item -r
3794 @itemx -R
3795 @itemx --recurse-limit
3796 @itemx --no-recurse-limit
3797 @itemx --recursion-limit
3798 @itemx --no-recursion-limit
3799 Enables or disables a limit on the amount of recursion performed
3800 whilst demangling strings. Since the name mangling formats allow for
3801 an inifinite level of recursion it is possible to create strings whose
3802 decoding will exhaust the amount of stack space available on the host
3803 machine, triggering a memory fault. The limit tries to prevent this
3804 from happening by restricting recursion to 2048 levels of nesting.
3805
3806 The default is for this limit to be enabled, but disabling it may be
3807 necessary in order to demangle truly complicated names. Note however
3808 that if the recursion limit is disabled then stack exhaustion is
3809 possible and any bug reports about such an event will be rejected.
3810
3811 The @option{-r} option is a synonym for the
3812 @option{--no-recurse-limit} option. The @option{-R} option is a
3813 synonym for the @option{--recurse-limit} option.
3814
3815 Note this option is only effective if the @option{-C} or
3816 @option{--demangle} option has been enabled.
3817
3818 @end table
3819
3820 @c man end
3821
3822 @ignore
3823 @c man begin SEEALSO addr2line
3824 Info entries for @file{binutils}.
3825 @c man end
3826 @end ignore
3827
3828 @node windmc
3829 @chapter windmc
3830
3831 @command{windmc} may be used to generator Windows message resources.
3832
3833 @quotation
3834 @emph{Warning:} @command{windmc} is not always built as part of the binary
3835 utilities, since it is only useful for Windows targets.
3836 @end quotation
3837
3838 @c man title windmc generates Windows message resources.
3839
3840 @smallexample
3841 @c man begin SYNOPSIS windmc
3842 windmc [options] input-file
3843 @c man end
3844 @end smallexample
3845
3846 @c man begin DESCRIPTION windmc
3847
3848 @command{windmc} reads message definitions from an input file (.mc) and
3849 translate them into a set of output files. The output files may be of
3850 four kinds:
3851
3852 @table @code
3853 @item h
3854 A C header file containing the message definitions.
3855
3856 @item rc
3857 A resource file compilable by the @command{windres} tool.
3858
3859 @item bin
3860 One or more binary files containing the resource data for a specific
3861 message language.
3862
3863 @item dbg
3864 A C include file that maps message id's to their symbolic name.
3865 @end table
3866
3867 The exact description of these different formats is available in
3868 documentation from Microsoft.
3869
3870 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3871 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3872 Windows Message Compiler.
3873
3874 @c man end
3875
3876 @c man begin OPTIONS windmc
3877
3878 @table @env
3879 @item -a
3880 @itemx --ascii_in
3881 Specifies that the input file specified is ASCII. This is the default
3882 behaviour.
3883
3884 @item -A
3885 @itemx --ascii_out
3886 Specifies that messages in the output @code{bin} files should be in ASCII
3887 format.
3888
3889 @item -b
3890 @itemx --binprefix
3891 Specifies that @code{bin} filenames should have to be prefixed by the
3892 basename of the source file.
3893
3894 @item -c
3895 @itemx --customflag
3896 Sets the customer bit in all message id's.
3897
3898 @item -C @var{codepage}
3899 @itemx --codepage_in @var{codepage}
3900 Sets the default codepage to be used to convert input file to UTF16. The
3901 default is ocdepage 1252.
3902
3903 @item -d
3904 @itemx --decimal_values
3905 Outputs the constants in the header file in decimal. Default is using
3906 hexadecimal output.
3907
3908 @item -e @var{ext}
3909 @itemx --extension @var{ext}
3910 The extension for the header file. The default is .h extension.
3911
3912 @item -F @var{target}
3913 @itemx --target @var{target}
3914 Specify the BFD format to use for a bin file as output. This
3915 is a BFD target name; you can use the @option{--help} option to see a list
3916 of supported targets. Normally @command{windmc} will use the default
3917 format, which is the first one listed by the @option{--help} option.
3918 @ifclear man
3919 @ref{Target Selection}.
3920 @end ifclear
3921
3922 @item -h @var{path}
3923 @itemx --headerdir @var{path}
3924 The target directory of the generated header file. The default is the
3925 current directory.
3926
3927 @item -H
3928 @itemx --help
3929 Displays a list of command-line options and then exits.
3930
3931 @item -m @var{characters}
3932 @itemx --maxlength @var{characters}
3933 Instructs @command{windmc} to generate a warning if the length
3934 of any message exceeds the number specified.
3935
3936 @item -n
3937 @itemx --nullterminate
3938 Terminate message text in @code{bin} files by zero. By default they are
3939 terminated by CR/LF.
3940
3941 @item -o
3942 @itemx --hresult_use
3943 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3944 file, using HRESULT definitions. Status codes are used if the flag is not
3945 specified.
3946
3947 @item -O @var{codepage}
3948 @itemx --codepage_out @var{codepage}
3949 Sets the default codepage to be used to output text files. The default
3950 is ocdepage 1252.
3951
3952 @item -r @var{path}
3953 @itemx --rcdir @var{path}
3954 The target directory for the generated @code{rc} script and the generated
3955 @code{bin} files that the resource compiler script includes. The default
3956 is the current directory.
3957
3958 @item -u
3959 @itemx --unicode_in
3960 Specifies that the input file is UTF16.
3961
3962 @item -U
3963 @itemx --unicode_out
3964 Specifies that messages in the output @code{bin} file should be in UTF16
3965 format. This is the default behaviour.
3966
3967 @item -v
3968 @item --verbose
3969 Enable verbose mode.
3970
3971 @item -V
3972 @item --version
3973 Prints the version number for @command{windmc}.
3974
3975 @item -x @var{path}
3976 @itemx --xdgb @var{path}
3977 The path of the @code{dbg} C include file that maps message id's to the
3978 symbolic name. No such file is generated without specifying the switch.
3979 @end table
3980
3981 @c man end
3982
3983 @ignore
3984 @c man begin SEEALSO windmc
3985 the Info entries for @file{binutils}.
3986 @c man end
3987 @end ignore
3988
3989 @node windres
3990 @chapter windres
3991
3992 @command{windres} may be used to manipulate Windows resources.
3993
3994 @quotation
3995 @emph{Warning:} @command{windres} is not always built as part of the binary
3996 utilities, since it is only useful for Windows targets.
3997 @end quotation
3998
3999 @c man title windres manipulate Windows resources.
4000
4001 @smallexample
4002 @c man begin SYNOPSIS windres
4003 windres [options] [input-file] [output-file]
4004 @c man end
4005 @end smallexample
4006
4007 @c man begin DESCRIPTION windres
4008
4009 @command{windres} reads resources from an input file and copies them into
4010 an output file. Either file may be in one of three formats:
4011
4012 @table @code
4013 @item rc
4014 A text format read by the Resource Compiler.
4015
4016 @item res
4017 A binary format generated by the Resource Compiler.
4018
4019 @item coff
4020 A COFF object or executable.
4021 @end table
4022
4023 The exact description of these different formats is available in
4024 documentation from Microsoft.
4025
4026 When @command{windres} converts from the @code{rc} format to the @code{res}
4027 format, it is acting like the Windows Resource Compiler. When
4028 @command{windres} converts from the @code{res} format to the @code{coff}
4029 format, it is acting like the Windows @code{CVTRES} program.
4030
4031 When @command{windres} generates an @code{rc} file, the output is similar
4032 but not identical to the format expected for the input. When an input
4033 @code{rc} file refers to an external filename, an output @code{rc} file
4034 will instead include the file contents.
4035
4036 If the input or output format is not specified, @command{windres} will
4037 guess based on the file name, or, for the input file, the file contents.
4038 A file with an extension of @file{.rc} will be treated as an @code{rc}
4039 file, a file with an extension of @file{.res} will be treated as a
4040 @code{res} file, and a file with an extension of @file{.o} or
4041 @file{.exe} will be treated as a @code{coff} file.
4042
4043 If no output file is specified, @command{windres} will print the resources
4044 in @code{rc} format to standard output.
4045
4046 The normal use is for you to write an @code{rc} file, use @command{windres}
4047 to convert it to a COFF object file, and then link the COFF file into
4048 your application. This will make the resources described in the
4049 @code{rc} file available to Windows.
4050
4051 @c man end
4052
4053 @c man begin OPTIONS windres
4054
4055 @table @env
4056 @item -i @var{filename}
4057 @itemx --input @var{filename}
4058 The name of the input file. If this option is not used, then
4059 @command{windres} will use the first non-option argument as the input file
4060 name. If there are no non-option arguments, then @command{windres} will
4061 read from standard input. @command{windres} can not read a COFF file from
4062 standard input.
4063
4064 @item -o @var{filename}
4065 @itemx --output @var{filename}
4066 The name of the output file. If this option is not used, then
4067 @command{windres} will use the first non-option argument, after any used
4068 for the input file name, as the output file name. If there is no
4069 non-option argument, then @command{windres} will write to standard output.
4070 @command{windres} can not write a COFF file to standard output. Note,
4071 for compatibility with @command{rc} the option @option{-fo} is also
4072 accepted, but its use is not recommended.
4073
4074 @item -J @var{format}
4075 @itemx --input-format @var{format}
4076 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4077 @samp{coff}. If no input format is specified, @command{windres} will
4078 guess, as described above.
4079
4080 @item -O @var{format}
4081 @itemx --output-format @var{format}
4082 The output format to generate. @var{format} may be @samp{res},
4083 @samp{rc}, or @samp{coff}. If no output format is specified,
4084 @command{windres} will guess, as described above.
4085
4086 @item -F @var{target}
4087 @itemx --target @var{target}
4088 Specify the BFD format to use for a COFF file as input or output. This
4089 is a BFD target name; you can use the @option{--help} option to see a list
4090 of supported targets. Normally @command{windres} will use the default
4091 format, which is the first one listed by the @option{--help} option.
4092 @ifclear man
4093 @ref{Target Selection}.
4094 @end ifclear
4095
4096 @item --preprocessor @var{program}
4097 When @command{windres} reads an @code{rc} file, it runs it through the C
4098 preprocessor first. This option may be used to specify the preprocessor
4099 to use, including any leading arguments. The default preprocessor
4100 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
4101
4102 @item --preprocessor-arg @var{option}
4103 When @command{windres} reads an @code{rc} file, it runs it through
4104 the C preprocessor first. This option may be used to specify additional
4105 text to be passed to preprocessor on its command line.
4106 This option can be used multiple times to add multiple options to the
4107 preprocessor command line.
4108
4109 @item -I @var{directory}
4110 @itemx --include-dir @var{directory}
4111 Specify an include directory to use when reading an @code{rc} file.
4112 @command{windres} will pass this to the preprocessor as an @option{-I}
4113 option. @command{windres} will also search this directory when looking for
4114 files named in the @code{rc} file. If the argument passed to this command
4115 matches any of the supported @var{formats} (as described in the @option{-J}
4116 option), it will issue a deprecation warning, and behave just like the
4117 @option{-J} option. New programs should not use this behaviour. If a
4118 directory happens to match a @var{format}, simple prefix it with @samp{./}
4119 to disable the backward compatibility.
4120
4121 @item -D @var{target}
4122 @itemx --define @var{sym}[=@var{val}]
4123 Specify a @option{-D} option to pass to the preprocessor when reading an
4124 @code{rc} file.
4125
4126 @item -U @var{target}
4127 @itemx --undefine @var{sym}
4128 Specify a @option{-U} option to pass to the preprocessor when reading an
4129 @code{rc} file.
4130
4131 @item -r
4132 Ignored for compatibility with rc.
4133
4134 @item -v
4135 Enable verbose mode. This tells you what the preprocessor is if you
4136 didn't specify one.
4137
4138 @item -c @var{val}
4139 @item --codepage @var{val}
4140 Specify the default codepage to use when reading an @code{rc} file.
4141 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4142 codepage code. The valid range is from zero up to 0xffff, but the
4143 validity of the codepage is host and configuration dependent.
4144
4145 @item -l @var{val}
4146 @item --language @var{val}
4147 Specify the default language to use when reading an @code{rc} file.
4148 @var{val} should be a hexadecimal language code. The low eight bits are
4149 the language, and the high eight bits are the sublanguage.
4150
4151 @item --use-temp-file
4152 Use a temporary file to instead of using popen to read the output of
4153 the preprocessor. Use this option if the popen implementation is buggy
4154 on the host (eg., certain non-English language versions of Windows 95 and
4155 Windows 98 are known to have buggy popen where the output will instead
4156 go the console).
4157
4158 @item --no-use-temp-file
4159 Use popen, not a temporary file, to read the output of the preprocessor.
4160 This is the default behaviour.
4161
4162 @item -h
4163 @item --help
4164 Prints a usage summary.
4165
4166 @item -V
4167 @item --version
4168 Prints the version number for @command{windres}.
4169
4170 @item --yydebug
4171 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4172 this will turn on parser debugging.
4173 @end table
4174
4175 @c man end
4176
4177 @ignore
4178 @c man begin SEEALSO windres
4179 the Info entries for @file{binutils}.
4180 @c man end
4181 @end ignore
4182
4183 @node dlltool
4184 @chapter dlltool
4185 @cindex DLL
4186 @kindex dlltool
4187
4188 @command{dlltool} is used to create the files needed to create dynamic
4189 link libraries (DLLs) on systems which understand PE format image
4190 files such as Windows. A DLL contains an export table which contains
4191 information that the runtime loader needs to resolve references from a
4192 referencing program.
4193
4194 The export table is generated by this program by reading in a
4195 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4196 will be in the DLL. A @file{.o} file can contain information in
4197 special @samp{.drectve} sections with export information.
4198
4199 @quotation
4200 @emph{Note:} @command{dlltool} is not always built as part of the
4201 binary utilities, since it is only useful for those targets which
4202 support DLLs.
4203 @end quotation
4204
4205 @c man title dlltool Create files needed to build and use DLLs.
4206
4207 @smallexample
4208 @c man begin SYNOPSIS dlltool
4209 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4210 [@option{-b}|@option{--base-file} @var{base-file-name}]
4211 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4212 [@option{-z}|@option{--output-def} @var{def-file-name}]
4213 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4214 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4215 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4216 [@option{--exclude-symbols} @var{list}]
4217 [@option{--no-default-excludes}]
4218 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4219 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4220 [@option{-a}|@option{--add-indirect}]
4221 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4222 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4223 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4224 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4225 [@option{--use-nul-prefixed-import-tables}]
4226 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4227 [@option{-i}|@option{--interwork}]
4228 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4229 [@option{-v}|@option{--verbose}]
4230 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4231 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4232 [object-file @dots{}]
4233 @c man end
4234 @end smallexample
4235
4236 @c man begin DESCRIPTION dlltool
4237
4238 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4239 @option{-b} options as well as object files specified on the command
4240 line. It then processes these inputs and if the @option{-e} option has
4241 been specified it creates a exports file. If the @option{-l} option
4242 has been specified it creates a library file and if the @option{-z} option
4243 has been specified it creates a def file. Any or all of the @option{-e},
4244 @option{-l} and @option{-z} options can be present in one invocation of
4245 dlltool.
4246
4247 When creating a DLL, along with the source for the DLL, it is necessary
4248 to have three other files. @command{dlltool} can help with the creation of
4249 these files.
4250
4251 The first file is a @file{.def} file which specifies which functions are
4252 exported from the DLL, which functions the DLL imports, and so on. This
4253 is a text file and can be created by hand, or @command{dlltool} can be used
4254 to create it using the @option{-z} option. In this case @command{dlltool}
4255 will scan the object files specified on its command line looking for
4256 those functions which have been specially marked as being exported and
4257 put entries for them in the @file{.def} file it creates.
4258
4259 In order to mark a function as being exported from a DLL, it needs to
4260 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4261 section of the object file. This can be done in C by using the
4262 asm() operator:
4263
4264 @smallexample
4265 asm (".section .drectve");
4266 asm (".ascii \"-export:my_func\"");
4267
4268 int my_func (void) @{ @dots{} @}
4269 @end smallexample
4270
4271 The second file needed for DLL creation is an exports file. This file
4272 is linked with the object files that make up the body of the DLL and it
4273 handles the interface between the DLL and the outside world. This is a
4274 binary file and it can be created by giving the @option{-e} option to
4275 @command{dlltool} when it is creating or reading in a @file{.def} file.
4276
4277 The third file needed for DLL creation is the library file that programs
4278 will link with in order to access the functions in the DLL (an `import
4279 library'). This file can be created by giving the @option{-l} option to
4280 dlltool when it is creating or reading in a @file{.def} file.
4281
4282 If the @option{-y} option is specified, dlltool generates a delay-import
4283 library that can be used instead of the normal import library to allow
4284 a program to link to the dll only as soon as an imported function is
4285 called for the first time. The resulting executable will need to be
4286 linked to the static delayimp library containing __delayLoadHelper2(),
4287 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4288
4289 @command{dlltool} builds the library file by hand, but it builds the
4290 exports file by creating temporary files containing assembler statements
4291 and then assembling these. The @option{-S} command-line option can be
4292 used to specify the path to the assembler that dlltool will use,
4293 and the @option{-f} option can be used to pass specific flags to that
4294 assembler. The @option{-n} can be used to prevent dlltool from deleting
4295 these temporary assembler files when it is done, and if @option{-n} is
4296 specified twice then this will prevent dlltool from deleting the
4297 temporary object files it used to build the library.
4298
4299 Here is an example of creating a DLL from a source file @samp{dll.c} and
4300 also creating a program (from an object file called @samp{program.o})
4301 that uses that DLL:
4302
4303 @smallexample
4304 gcc -c dll.c
4305 dlltool -e exports.o -l dll.lib dll.o
4306 gcc dll.o exports.o -o dll.dll
4307 gcc program.o dll.lib -o program
4308 @end smallexample
4309
4310
4311 @command{dlltool} may also be used to query an existing import library
4312 to determine the name of the DLL to which it is associated. See the
4313 description of the @option{-I} or @option{--identify} option.
4314
4315 @c man end
4316
4317 @c man begin OPTIONS dlltool
4318
4319 The command-line options have the following meanings:
4320
4321 @table @env
4322
4323 @item -d @var{filename}
4324 @itemx --input-def @var{filename}
4325 @cindex input .def file
4326 Specifies the name of a @file{.def} file to be read in and processed.
4327
4328 @item -b @var{filename}
4329 @itemx --base-file @var{filename}
4330 @cindex base files
4331 Specifies the name of a base file to be read in and processed. The
4332 contents of this file will be added to the relocation section in the
4333 exports file generated by dlltool.
4334
4335 @item -e @var{filename}
4336 @itemx --output-exp @var{filename}
4337 Specifies the name of the export file to be created by dlltool.
4338
4339 @item -z @var{filename}
4340 @itemx --output-def @var{filename}
4341 Specifies the name of the @file{.def} file to be created by dlltool.
4342
4343 @item -l @var{filename}
4344 @itemx --output-lib @var{filename}
4345 Specifies the name of the library file to be created by dlltool.
4346
4347 @item -y @var{filename}
4348 @itemx --output-delaylib @var{filename}
4349 Specifies the name of the delay-import library file to be created by dlltool.
4350
4351 @item --export-all-symbols
4352 Treat all global and weak defined symbols found in the input object
4353 files as symbols to be exported. There is a small list of symbols which
4354 are not exported by default; see the @option{--no-default-excludes}
4355 option. You may add to the list of symbols to not export by using the
4356 @option{--exclude-symbols} option.
4357
4358 @item --no-export-all-symbols
4359 Only export symbols explicitly listed in an input @file{.def} file or in
4360 @samp{.drectve} sections in the input object files. This is the default
4361 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4362 attributes in the source code.
4363
4364 @item --exclude-symbols @var{list}
4365 Do not export the symbols in @var{list}. This is a list of symbol names
4366 separated by comma or colon characters. The symbol names should not
4367 contain a leading underscore. This is only meaningful when
4368 @option{--export-all-symbols} is used.
4369
4370 @item --no-default-excludes
4371 When @option{--export-all-symbols} is used, it will by default avoid
4372 exporting certain special symbols. The current list of symbols to avoid
4373 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4374 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4375 to go ahead and export these special symbols. This is only meaningful
4376 when @option{--export-all-symbols} is used.
4377
4378 @item -S @var{path}
4379 @itemx --as @var{path}
4380 Specifies the path, including the filename, of the assembler to be used
4381 to create the exports file.
4382
4383 @item -f @var{options}
4384 @itemx --as-flags @var{options}
4385 Specifies any specific command-line options to be passed to the
4386 assembler when building the exports file. This option will work even if
4387 the @option{-S} option is not used. This option only takes one argument,
4388 and if it occurs more than once on the command line, then later
4389 occurrences will override earlier occurrences. So if it is necessary to
4390 pass multiple options to the assembler they should be enclosed in
4391 double quotes.
4392
4393 @item -D @var{name}
4394 @itemx --dll-name @var{name}
4395 Specifies the name to be stored in the @file{.def} file as the name of
4396 the DLL when the @option{-e} option is used. If this option is not
4397 present, then the filename given to the @option{-e} option will be
4398 used as the name of the DLL.
4399
4400 @item -m @var{machine}
4401 @itemx -machine @var{machine}
4402 Specifies the type of machine for which the library file should be
4403 built. @command{dlltool} has a built in default type, depending upon how
4404 it was created, but this option can be used to override that. This is
4405 normally only useful when creating DLLs for an ARM processor, when the
4406 contents of the DLL are actually encode using Thumb instructions.
4407
4408 @item -a
4409 @itemx --add-indirect
4410 Specifies that when @command{dlltool} is creating the exports file it
4411 should add a section which allows the exported functions to be
4412 referenced without using the import library. Whatever the hell that
4413 means!
4414
4415 @item -U
4416 @itemx --add-underscore
4417 Specifies that when @command{dlltool} is creating the exports file it
4418 should prepend an underscore to the names of @emph{all} exported symbols.
4419
4420 @item --no-leading-underscore
4421 @item --leading-underscore
4422 Specifies whether standard symbol should be forced to be prefixed, or
4423 not.
4424
4425 @item --add-stdcall-underscore
4426 Specifies that when @command{dlltool} is creating the exports file it
4427 should prepend an underscore to the names of exported @emph{stdcall}
4428 functions. Variable names and non-stdcall function names are not modified.
4429 This option is useful when creating GNU-compatible import libs for third
4430 party DLLs that were built with MS-Windows tools.
4431
4432 @item -k
4433 @itemx --kill-at
4434 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4435 of stdcall functions that will be imported from the DLL. This is
4436 useful when creating an import library for a DLL which exports stdcall
4437 functions but without the usual @samp{@@<number>} symbol name suffix.
4438
4439 This does not change the naming of symbols provided by the import library
4440 to programs linked against it, but only the entries in the import table
4441 (ie the .idata section).
4442
4443 @item -A
4444 @itemx --add-stdcall-alias
4445 Specifies that when @command{dlltool} is creating the exports file it
4446 should add aliases for stdcall symbols without @samp{@@ <number>}
4447 in addition to the symbols with @samp{@@ <number>}.
4448
4449 @item -p
4450 @itemx --ext-prefix-alias @var{prefix}
4451 Causes @command{dlltool} to create external aliases for all DLL
4452 imports with the specified prefix. The aliases are created for both
4453 external and import symbols with no leading underscore.
4454
4455 @item -x
4456 @itemx --no-idata4
4457 Specifies that when @command{dlltool} is creating the exports and library
4458 files it should omit the @code{.idata4} section. This is for compatibility
4459 with certain operating systems.
4460
4461 @item --use-nul-prefixed-import-tables
4462 Specifies that when @command{dlltool} is creating the exports and library
4463 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4464 element. This emulates old gnu import library generation of
4465 @code{dlltool}. By default this option is turned off.
4466
4467 @item -c
4468 @itemx --no-idata5
4469 Specifies that when @command{dlltool} is creating the exports and library
4470 files it should omit the @code{.idata5} section. This is for compatibility
4471 with certain operating systems.
4472
4473 @item -I @var{filename}
4474 @itemx --identify @var{filename}
4475 Specifies that @command{dlltool} should inspect the import library
4476 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4477 of the associated DLL(s). This can be performed in addition to any
4478 other operations indicated by the other options and arguments.
4479 @command{dlltool} fails if the import library does not exist or is not
4480 actually an import library. See also @option{--identify-strict}.
4481
4482 @item --identify-strict
4483 Modifies the behavior of the @option{--identify} option, such
4484 that an error is reported if @var{filename} is associated with
4485 more than one DLL.
4486
4487 @item -i
4488 @itemx --interwork
4489 Specifies that @command{dlltool} should mark the objects in the library
4490 file and exports file that it produces as supporting interworking
4491 between ARM and Thumb code.
4492
4493 @item -n
4494 @itemx --nodelete
4495 Makes @command{dlltool} preserve the temporary assembler files it used to
4496 create the exports file. If this option is repeated then dlltool will
4497 also preserve the temporary object files it uses to create the library
4498 file.
4499
4500 @item -t @var{prefix}
4501 @itemx --temp-prefix @var{prefix}
4502 Makes @command{dlltool} use @var{prefix} when constructing the names of
4503 temporary assembler and object files. By default, the temp file prefix
4504 is generated from the pid.
4505
4506 @item -v
4507 @itemx --verbose
4508 Make dlltool describe what it is doing.
4509
4510 @item -h
4511 @itemx --help
4512 Displays a list of command-line options and then exits.
4513
4514 @item -V
4515 @itemx --version
4516 Displays dlltool's version number and then exits.
4517
4518 @end table
4519
4520 @c man end
4521
4522 @menu
4523 * def file format:: The format of the dlltool @file{.def} file
4524 @end menu
4525
4526 @node def file format
4527 @section The format of the @command{dlltool} @file{.def} file
4528
4529 A @file{.def} file contains any number of the following commands:
4530
4531 @table @asis
4532
4533 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4534 The result is going to be named @var{name}@code{.exe}.
4535
4536 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4537 The result is going to be named @var{name}@code{.dll}.
4538 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4539 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4540 details).
4541
4542 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4543 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4544 Declares @var{name1} as an exported symbol from the DLL, with optional
4545 ordinal number @var{integer}, or declares @var{name1} as an alias
4546 (forward) of the function @var{external-name} in the DLL.
4547 If @var{its_name} is specified, this name is used as string in export table.
4548 @var{module-name}.
4549 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4550 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4551 If you want to use LIBRARY as name then you need to quote it.
4552
4553 @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{]} *}
4554 Declares that @var{external-name} or the exported function whose
4555 ordinal number is @var{integer} is to be imported from the file
4556 @var{module-name}. If @var{internal-name} is specified then this is
4557 the name that the imported function will be referred to in the body of
4558 the DLL.
4559 If @var{its_name} is specified, this name is used as string in import table.
4560 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4561 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4562 If you want to use LIBRARY as name then you need to quote it.
4563
4564 @item @code{DESCRIPTION} @var{string}
4565 Puts @var{string} into the output @file{.exp} file in the
4566 @code{.rdata} section.
4567
4568 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4569 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4570 Generates @code{--stack} or @code{--heap}
4571 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4572 section. The linker will see this and act upon it.
4573
4574 @item @code{CODE} @var{attr} @code{+}
4575 @item @code{DATA} @var{attr} @code{+}
4576 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4577 Generates @code{--attr} @var{section-name} @var{attr} in the output
4578 @code{.drectve} section, where @var{attr} is one of @code{READ},
4579 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4580 this and act upon it.
4581
4582 @end table
4583
4584 @ignore
4585 @c man begin SEEALSO dlltool
4586 The Info pages for @file{binutils}.
4587 @c man end
4588 @end ignore
4589
4590 @node readelf
4591 @chapter readelf
4592
4593 @cindex ELF file information
4594 @kindex readelf
4595
4596 @c man title readelf Displays information about ELF files.
4597
4598 @smallexample
4599 @c man begin SYNOPSIS readelf
4600 readelf [@option{-a}|@option{--all}]
4601 [@option{-h}|@option{--file-header}]
4602 [@option{-l}|@option{--program-headers}|@option{--segments}]
4603 [@option{-S}|@option{--section-headers}|@option{--sections}]
4604 [@option{-g}|@option{--section-groups}]
4605 [@option{-t}|@option{--section-details}]
4606 [@option{-e}|@option{--headers}]
4607 [@option{-s}|@option{--syms}|@option{--symbols}]
4608 [@option{--dyn-syms}]
4609 [@option{-n}|@option{--notes}]
4610 [@option{-r}|@option{--relocs}]
4611 [@option{-u}|@option{--unwind}]
4612 [@option{-d}|@option{--dynamic}]
4613 [@option{-V}|@option{--version-info}]
4614 [@option{-A}|@option{--arch-specific}]
4615 [@option{-D}|@option{--use-dynamic}]
4616 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4617 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4618 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4619 [@option{-z}|@option{--decompress}]
4620 [@option{-c}|@option{--archive-index}]
4621 [@option{-w[lLiaprmfFsoRtUuTgAckK]}|
4622 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]]
4623 [@option{--dwarf-depth=@var{n}}]
4624 [@option{--dwarf-start=@var{n}}]
4625 [@option{-I}|@option{--histogram}]
4626 [@option{-v}|@option{--version}]
4627 [@option{-W}|@option{--wide}]
4628 [@option{-H}|@option{--help}]
4629 @var{elffile}@dots{}
4630 @c man end
4631 @end smallexample
4632
4633 @c man begin DESCRIPTION readelf
4634
4635 @command{readelf} displays information about one or more ELF format object
4636 files. The options control what particular information to display.
4637
4638 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4639 64-bit ELF files are supported, as are archives containing ELF files.
4640
4641 This program performs a similar function to @command{objdump} but it
4642 goes into more detail and it exists independently of the @sc{bfd}
4643 library, so if there is a bug in @sc{bfd} then readelf will not be
4644 affected.
4645
4646 @c man end
4647
4648 @c man begin OPTIONS readelf
4649
4650 The long and short forms of options, shown here as alternatives, are
4651 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4652 given.
4653
4654 @table @env
4655 @item -a
4656 @itemx --all
4657 Equivalent to specifying @option{--file-header},
4658 @option{--program-headers}, @option{--sections}, @option{--symbols},
4659 @option{--relocs}, @option{--dynamic}, @option{--notes},
4660 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4661 @option{--section-groups} and @option{--histogram}.
4662
4663 Note - this option does not enable @option{--use-dynamic} itself, so
4664 if that option is not present on the command line then dynamic symbols
4665 and dynamic relocs will not be displayed.
4666
4667 @item -h
4668 @itemx --file-header
4669 @cindex ELF file header information
4670 Displays the information contained in the ELF header at the start of the
4671 file.
4672
4673 @item -l
4674 @itemx --program-headers
4675 @itemx --segments
4676 @cindex ELF program header information
4677 @cindex ELF segment information
4678 Displays the information contained in the file's segment headers, if it
4679 has any.
4680
4681 @item -S
4682 @itemx --sections
4683 @itemx --section-headers
4684 @cindex ELF section information
4685 Displays the information contained in the file's section headers, if it
4686 has any.
4687
4688 @item -g
4689 @itemx --section-groups
4690 @cindex ELF section group information
4691 Displays the information contained in the file's section groups, if it
4692 has any.
4693
4694 @item -t
4695 @itemx --section-details
4696 @cindex ELF section information
4697 Displays the detailed section information. Implies @option{-S}.
4698
4699 @item -s
4700 @itemx --symbols
4701 @itemx --syms
4702 @cindex ELF symbol table information
4703 Displays the entries in symbol table section of the file, if it has one.
4704 If a symbol has version information associated with it then this is
4705 displayed as well. The version string is displayed as a suffix to the
4706 symbol name, preceeded by an @@ character. For example
4707 @samp{foo@@VER_1}. If the version is the default version to be used
4708 when resolving unversioned references to the symbol then it is
4709 displayed as a suffix preceeded by two @@ characters. For example
4710 @samp{foo@@@@VER_2}.
4711
4712 @item --dyn-syms
4713 @cindex ELF dynamic symbol table information
4714 Displays the entries in dynamic symbol table section of the file, if it
4715 has one. The output format is the same as the format used by the
4716 @option{--syms} option.
4717
4718 @item -e
4719 @itemx --headers
4720 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4721
4722 @item -n
4723 @itemx --notes
4724 @cindex ELF notes
4725 Displays the contents of the NOTE segments and/or sections, if any.
4726
4727 @item -r
4728 @itemx --relocs
4729 @cindex ELF reloc information
4730 Displays the contents of the file's relocation section, if it has one.
4731
4732 @item -u
4733 @itemx --unwind
4734 @cindex unwind information
4735 Displays the contents of the file's unwind section, if it has one. Only
4736 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4737 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
4738 support is not yet implemented for your architecture you could try
4739 dumping the contents of the @var{.eh_frames} section using the
4740 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
4741 options.
4742
4743 @item -d
4744 @itemx --dynamic
4745 @cindex ELF dynamic section information
4746 Displays the contents of the file's dynamic section, if it has one.
4747
4748 @item -V
4749 @itemx --version-info
4750 @cindex ELF version sections information
4751 Displays the contents of the version sections in the file, it they
4752 exist.
4753
4754 @item -A
4755 @itemx --arch-specific
4756 Displays architecture-specific information in the file, if there
4757 is any.
4758
4759 @item -D
4760 @itemx --use-dynamic
4761 When displaying symbols, this option makes @command{readelf} use the
4762 symbol hash tables in the file's dynamic section, rather than the
4763 symbol table sections.
4764
4765 When displaying relocations, this option makes @command{readelf}
4766 display the dynamic relocations rather than the static relocations.
4767
4768 @item -x <number or name>
4769 @itemx --hex-dump=<number or name>
4770 Displays the contents of the indicated section as a hexadecimal bytes.
4771 A number identifies a particular section by index in the section table;
4772 any other string identifies all sections with that name in the object file.
4773
4774 @item -R <number or name>
4775 @itemx --relocated-dump=<number or name>
4776 Displays the contents of the indicated section as a hexadecimal
4777 bytes. A number identifies a particular section by index in the
4778 section table; any other string identifies all sections with that name
4779 in the object file. The contents of the section will be relocated
4780 before they are displayed.
4781
4782 @item -p <number or name>
4783 @itemx --string-dump=<number or name>
4784 Displays the contents of the indicated section as printable strings.
4785 A number identifies a particular section by index in the section table;
4786 any other string identifies all sections with that name in the object file.
4787
4788 @item -z
4789 @itemx --decompress
4790 Requests that the section(s) being dumped by @option{x}, @option{R} or
4791 @option{p} options are decompressed before being displayed. If the
4792 section(s) are not compressed then they are displayed as is.
4793
4794 @item -c
4795 @itemx --archive-index
4796 @cindex Archive file symbol index information
4797 Displays the file symbol index information contained in the header part
4798 of binary archives. Performs the same function as the @option{t}
4799 command to @command{ar}, but without using the BFD library. @xref{ar}.
4800
4801 @item -w[lLiaprmfFsoRtUuTgAckK]
4802 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
4803 @include debug.options.texi
4804
4805 @item -I
4806 @itemx --histogram
4807 Display a histogram of bucket list lengths when displaying the contents
4808 of the symbol tables.
4809
4810 @item -v
4811 @itemx --version
4812 Display the version number of readelf.
4813
4814 @item -W
4815 @itemx --wide
4816 Don't break output lines to fit into 80 columns. By default
4817 @command{readelf} breaks section header and segment listing lines for
4818 64-bit ELF files, so that they fit into 80 columns. This option causes
4819 @command{readelf} to print each section header resp. each segment one a
4820 single line, which is far more readable on terminals wider than 80 columns.
4821
4822 @item -H
4823 @itemx --help
4824 Display the command-line options understood by @command{readelf}.
4825
4826 @end table
4827
4828 @c man end
4829
4830 @ignore
4831 @c man begin SEEALSO readelf
4832 objdump(1), and the Info entries for @file{binutils}.
4833 @c man end
4834 @end ignore
4835
4836 @node elfedit
4837 @chapter elfedit
4838
4839 @cindex Update ELF header
4840 @kindex elfedit
4841
4842 @c man title elfedit Update ELF header and program property of ELF files.
4843
4844 @smallexample
4845 @c man begin SYNOPSIS elfedit
4846 elfedit [@option{--input-mach=}@var{machine}]
4847 [@option{--input-type=}@var{type}]
4848 [@option{--input-osabi=}@var{osabi}]
4849 @option{--output-mach=}@var{machine}
4850 @option{--output-type=}@var{type}
4851 @option{--output-osabi=}@var{osabi}
4852 @option{--enable-x86-feature=}@var{feature}
4853 @option{--disable-x86-feature=}@var{feature}
4854 [@option{-v}|@option{--version}]
4855 [@option{-h}|@option{--help}]
4856 @var{elffile}@dots{}
4857 @c man end
4858 @end smallexample
4859
4860 @c man begin DESCRIPTION elfedit
4861
4862 @command{elfedit} updates the ELF header and program property of ELF
4863 files which have the matching ELF machine and file types. The options
4864 control how and which fields in the ELF header and program property
4865 should be updated.
4866
4867 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4868 64-bit ELF files are supported, as are archives containing ELF files.
4869 @c man end
4870
4871 @c man begin OPTIONS elfedit
4872
4873 The long and short forms of options, shown here as alternatives, are
4874 equivalent. At least one of the @option{--output-mach},
4875 @option{--output-type}, @option{--output-osabi},
4876 @option{--enable-x86-feature} and @option{--disable-x86-feature}
4877 options must be given.
4878
4879 @table @env
4880
4881 @item --input-mach=@var{machine}
4882 Set the matching input ELF machine type to @var{machine}. If
4883 @option{--input-mach} isn't specified, it will match any ELF
4884 machine types.
4885
4886 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4887 @var{K1OM} and @var{x86-64}.
4888
4889 @item --output-mach=@var{machine}
4890 Change the ELF machine type in the ELF header to @var{machine}. The
4891 supported ELF machine types are the same as @option{--input-mach}.
4892
4893 @item --input-type=@var{type}
4894 Set the matching input ELF file type to @var{type}. If
4895 @option{--input-type} isn't specified, it will match any ELF file types.
4896
4897 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4898
4899 @item --output-type=@var{type}
4900 Change the ELF file type in the ELF header to @var{type}. The
4901 supported ELF types are the same as @option{--input-type}.
4902
4903 @item --input-osabi=@var{osabi}
4904 Set the matching input ELF file OSABI to @var{osabi}. If
4905 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4906
4907 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4908 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4909 @var{Solaris}, @var{AIX}, @var{Irix},
4910 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4911 @var{NSK}, @var{AROS} and @var{FenixOS}.
4912
4913 @item --output-osabi=@var{osabi}
4914 Change the ELF OSABI in the ELF header to @var{osabi}. The
4915 supported ELF OSABI are the same as @option{--input-osabi}.
4916
4917 @item --enable-x86-feature=@var{feature}
4918 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
4919 ELF files with machine types of @var{i386} or @var{x86-64}. The
4920 supported features are, @var{ibt} and @var{shstk}.
4921
4922 @item --disable-x86-feature=@var{feature}
4923 Clear the @var{feature} bit in program property in @var{exec} or
4924 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
4925 The supported features are the same as @option{--enable-x86-feature}.
4926
4927 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
4928 are available only on hosts with @samp{mmap} support.
4929
4930 @item -v
4931 @itemx --version
4932 Display the version number of @command{elfedit}.
4933
4934 @item -h
4935 @itemx --help
4936 Display the command-line options understood by @command{elfedit}.
4937
4938 @end table
4939
4940 @c man end
4941
4942 @ignore
4943 @c man begin SEEALSO elfedit
4944 readelf(1), and the Info entries for @file{binutils}.
4945 @c man end
4946 @end ignore
4947
4948 @node Common Options
4949 @chapter Common Options
4950
4951 The following command-line options are supported by all of the
4952 programs described in this manual.
4953
4954 @c man begin OPTIONS
4955 @table @env
4956 @include at-file.texi
4957 @c man end
4958
4959 @item --help
4960 Display the command-line options supported by the program.
4961
4962 @item --version
4963 Display the version number of the program.
4964
4965 @c man begin OPTIONS
4966 @end table
4967 @c man end
4968
4969 @node Selecting the Target System
4970 @chapter Selecting the Target System
4971
4972 You can specify two aspects of the target system to the @sc{gnu}
4973 binary file utilities, each in several ways:
4974
4975 @itemize @bullet
4976 @item
4977 the target
4978
4979 @item
4980 the architecture
4981 @end itemize
4982
4983 In the following summaries, the lists of ways to specify values are in
4984 order of decreasing precedence. The ways listed first override those
4985 listed later.
4986
4987 The commands to list valid values only list the values for which the
4988 programs you are running were configured. If they were configured with
4989 @option{--enable-targets=all}, the commands list most of the available
4990 values, but a few are left out; not all targets can be configured in at
4991 once because some of them can only be configured @dfn{native} (on hosts
4992 with the same type as the target system).
4993
4994 @menu
4995 * Target Selection::
4996 * Architecture Selection::
4997 @end menu
4998
4999 @node Target Selection
5000 @section Target Selection
5001
5002 A @dfn{target} is an object file format. A given target may be
5003 supported for multiple architectures (@pxref{Architecture Selection}).
5004 A target selection may also have variations for different operating
5005 systems or architectures.
5006
5007 The command to list valid target values is @samp{objdump -i}
5008 (the first column of output contains the relevant information).
5009
5010 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5011 @samp{a.out-sunos-big}.
5012
5013 You can also specify a target using a configuration triplet. This is
5014 the same sort of name that is passed to @file{configure} to specify a
5015 target. When you use a configuration triplet as an argument, it must be
5016 fully canonicalized. You can see the canonical version of a triplet by
5017 running the shell script @file{config.sub} which is included with the
5018 sources.
5019
5020 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5021 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5022
5023 @subheading @command{objdump} Target
5024
5025 Ways to specify:
5026
5027 @enumerate
5028 @item
5029 command-line option: @option{-b} or @option{--target}
5030
5031 @item
5032 environment variable @code{GNUTARGET}
5033
5034 @item
5035 deduced from the input file
5036 @end enumerate
5037
5038 @subheading @command{objcopy} and @command{strip} Input Target
5039
5040 Ways to specify:
5041
5042 @enumerate
5043 @item
5044 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5045
5046 @item
5047 environment variable @code{GNUTARGET}
5048
5049 @item
5050 deduced from the input file
5051 @end enumerate
5052
5053 @subheading @command{objcopy} and @command{strip} Output Target
5054
5055 Ways to specify:
5056
5057 @enumerate
5058 @item
5059 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5060
5061 @item
5062 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5063
5064 @item
5065 environment variable @code{GNUTARGET}
5066
5067 @item
5068 deduced from the input file
5069 @end enumerate
5070
5071 @subheading @command{nm}, @command{size}, and @command{strings} Target
5072
5073 Ways to specify:
5074
5075 @enumerate
5076 @item
5077 command-line option: @option{--target}
5078
5079 @item
5080 environment variable @code{GNUTARGET}
5081
5082 @item
5083 deduced from the input file
5084 @end enumerate
5085
5086 @node Architecture Selection
5087 @section Architecture Selection
5088
5089 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5090 to run. Its name may contain a colon, separating the name of the
5091 processor family from the name of the particular @sc{cpu}.
5092
5093 The command to list valid architecture values is @samp{objdump -i} (the
5094 second column contains the relevant information).
5095
5096 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5097
5098 @subheading @command{objdump} Architecture
5099
5100 Ways to specify:
5101
5102 @enumerate
5103 @item
5104 command-line option: @option{-m} or @option{--architecture}
5105
5106 @item
5107 deduced from the input file
5108 @end enumerate
5109
5110 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5111
5112 Ways to specify:
5113
5114 @enumerate
5115 @item
5116 deduced from the input file
5117 @end enumerate
5118
5119 @node Reporting Bugs
5120 @chapter Reporting Bugs
5121 @cindex bugs
5122 @cindex reporting bugs
5123
5124 Your bug reports play an essential role in making the binary utilities
5125 reliable.
5126
5127 Reporting a bug may help you by bringing a solution to your problem, or
5128 it may not. But in any case the principal function of a bug report is
5129 to help the entire community by making the next version of the binary
5130 utilities work better. Bug reports are your contribution to their
5131 maintenance.
5132
5133 In order for a bug report to serve its purpose, you must include the
5134 information that enables us to fix the bug.
5135
5136 @menu
5137 * Bug Criteria:: Have you found a bug?
5138 * Bug Reporting:: How to report bugs
5139 @end menu
5140
5141 @node Bug Criteria
5142 @section Have You Found a Bug?
5143 @cindex bug criteria
5144
5145 If you are not sure whether you have found a bug, here are some guidelines:
5146
5147 @itemize @bullet
5148 @cindex fatal signal
5149 @cindex crash
5150 @item
5151 If a binary utility gets a fatal signal, for any input whatever, that is
5152 a bug. Reliable utilities never crash.
5153
5154 @cindex error on valid input
5155 @item
5156 If a binary utility produces an error message for valid input, that is a
5157 bug.
5158
5159 @item
5160 If you are an experienced user of binary utilities, your suggestions for
5161 improvement are welcome in any case.
5162 @end itemize
5163
5164 @node Bug Reporting
5165 @section How to Report Bugs
5166 @cindex bug reports
5167 @cindex bugs, reporting
5168
5169 A number of companies and individuals offer support for @sc{gnu}
5170 products. If you obtained the binary utilities from a support
5171 organization, we recommend you contact that organization first.
5172
5173 You can find contact information for many support companies and
5174 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5175 distribution.
5176
5177 @ifset BUGURL
5178 In any event, we also recommend that you send bug reports for the binary
5179 utilities to @value{BUGURL}.
5180 @end ifset
5181
5182 The fundamental principle of reporting bugs usefully is this:
5183 @strong{report all the facts}. If you are not sure whether to state a
5184 fact or leave it out, state it!
5185
5186 Often people omit facts because they think they know what causes the
5187 problem and assume that some details do not matter. Thus, you might
5188 assume that the name of a file you use in an example does not matter.
5189 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5190 a stray memory reference which happens to fetch from the location where
5191 that pathname is stored in memory; perhaps, if the pathname were
5192 different, the contents of that location would fool the utility into
5193 doing the right thing despite the bug. Play it safe and give a
5194 specific, complete example. That is the easiest thing for you to do,
5195 and the most helpful.
5196
5197 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5198 it is new to us. Therefore, always write your bug reports on the assumption
5199 that the bug has not been reported previously.
5200
5201 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5202 bell?'' This cannot help us fix a bug, so it is basically useless. We
5203 respond by asking for enough details to enable us to investigate.
5204 You might as well expedite matters by sending them to begin with.
5205
5206 To enable us to fix the bug, you should include all these things:
5207
5208 @itemize @bullet
5209 @item
5210 The version of the utility. Each utility announces it if you start it
5211 with the @option{--version} argument.
5212
5213 Without this, we will not know whether there is any point in looking for
5214 the bug in the current version of the binary utilities.
5215
5216 @item
5217 Any patches you may have applied to the source, including any patches
5218 made to the @code{BFD} library.
5219
5220 @item
5221 The type of machine you are using, and the operating system name and
5222 version number.
5223
5224 @item
5225 What compiler (and its version) was used to compile the utilities---e.g.
5226 ``@code{gcc-2.7}''.
5227
5228 @item
5229 The command arguments you gave the utility to observe the bug. To
5230 guarantee you will not omit something important, list them all. A copy
5231 of the Makefile (or the output from make) is sufficient.
5232
5233 If we were to try to guess the arguments, we would probably guess wrong
5234 and then we might not encounter the bug.
5235
5236 @item
5237 A complete input file, or set of input files, that will reproduce the
5238 bug. If the utility is reading an object file or files, then it is
5239 generally most helpful to send the actual object files.
5240
5241 If the source files were produced exclusively using @sc{gnu} programs
5242 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5243 may be OK to send the source files rather than the object files. In
5244 this case, be sure to say exactly what version of @command{gcc}, or
5245 whatever, was used to produce the object files. Also say how
5246 @command{gcc}, or whatever, was configured.
5247
5248 @item
5249 A description of what behavior you observe that you believe is
5250 incorrect. For example, ``It gets a fatal signal.''
5251
5252 Of course, if the bug is that the utility gets a fatal signal, then we
5253 will certainly notice it. But if the bug is incorrect output, we might
5254 not notice unless it is glaringly wrong. You might as well not give us
5255 a chance to make a mistake.
5256
5257 Even if the problem you experience is a fatal signal, you should still
5258 say so explicitly. Suppose something strange is going on, such as your
5259 copy of the utility is out of sync, or you have encountered a bug in
5260 the C library on your system. (This has happened!) Your copy might
5261 crash and ours would not. If you told us to expect a crash, then when
5262 ours fails to crash, we would know that the bug was not happening for
5263 us. If you had not told us to expect a crash, then we would not be able
5264 to draw any conclusion from our observations.
5265
5266 @item
5267 If you wish to suggest changes to the source, send us context diffs, as
5268 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5269 option. Always send diffs from the old file to the new file. If you
5270 wish to discuss something in the @command{ld} source, refer to it by
5271 context, not by line number.
5272
5273 The line numbers in our development sources will not match those in your
5274 sources. Your line numbers would convey no useful information to us.
5275 @end itemize
5276
5277 Here are some things that are not necessary:
5278
5279 @itemize @bullet
5280 @item
5281 A description of the envelope of the bug.
5282
5283 Often people who encounter a bug spend a lot of time investigating
5284 which changes to the input file will make the bug go away and which
5285 changes will not affect it.
5286
5287 This is often time consuming and not very useful, because the way we
5288 will find the bug is by running a single example under the debugger
5289 with breakpoints, not by pure deduction from a series of examples.
5290 We recommend that you save your time for something else.
5291
5292 Of course, if you can find a simpler example to report @emph{instead}
5293 of the original one, that is a convenience for us. Errors in the
5294 output will be easier to spot, running under the debugger will take
5295 less time, and so on.
5296
5297 However, simplification is not vital; if you do not want to do this,
5298 report the bug anyway and send us the entire test case you used.
5299
5300 @item
5301 A patch for the bug.
5302
5303 A patch for the bug does help us if it is a good one. But do not omit
5304 the necessary information, such as the test case, on the assumption that
5305 a patch is all we need. We might see problems with your patch and decide
5306 to fix the problem another way, or we might not understand it at all.
5307
5308 Sometimes with programs as complicated as the binary utilities it is
5309 very hard to construct an example that will make the program follow a
5310 certain path through the code. If you do not send us the example, we
5311 will not be able to construct one, so we will not be able to verify that
5312 the bug is fixed.
5313
5314 And if we cannot understand what bug you are trying to fix, or why your
5315 patch should be an improvement, we will not install it. A test case will
5316 help us to understand.
5317
5318 @item
5319 A guess about what the bug is or what it depends on.
5320
5321 Such guesses are usually wrong. Even we cannot guess right about such
5322 things without first using the debugger to find the facts.
5323 @end itemize
5324
5325 @node GNU Free Documentation License
5326 @appendix GNU Free Documentation License
5327
5328 @include fdl.texi
5329
5330 @node Binutils Index
5331 @unnumbered Binutils Index
5332
5333 @printindex cp
5334
5335 @bye