Fix debug section compression so that it is only performed if it would make the secti...
[deliverable/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{} 1991-2015 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 * nlmconv: (binutils)nlmconv. Converts object code into an NLM.
38 * nm: (binutils)nm. List symbols from object files.
39 * objcopy: (binutils)objcopy. Copy and translate object files.
40 * objdump: (binutils)objdump. Display information from object files.
41 * ranlib: (binutils)ranlib. Generate index to archive contents.
42 * readelf: (binutils)readelf. Display the contents of ELF format files.
43 * size: (binutils)size. List section sizes and total size.
44 * strings: (binutils)strings. List printable strings from files.
45 * strip: (binutils)strip. Discard symbols.
46 * elfedit: (binutils)elfedit. Update the ELF header of ELF files.
47 * windmc: (binutils)windmc. Generator for Windows message resources.
48 * windres: (binutils)windres. Manipulate Windows resources.
49 @end direntry
50
51 @titlepage
52 @title The @sc{gnu} Binary Utilities
53 @ifset VERSION_PACKAGE
54 @subtitle @value{VERSION_PACKAGE}
55 @end ifset
56 @subtitle Version @value{VERSION}
57 @sp 1
58 @subtitle @value{UPDATED}
59 @author Roland H. Pesch
60 @author Jeffrey M. Osier
61 @author Cygnus Support
62 @page
63
64 @tex
65 {\parskip=0pt \hfill Cygnus Support\par \hfill
66 Texinfo \texinfoversion\par }
67 @end tex
68
69 @vskip 0pt plus 1filll
70 @insertcopying
71 @end titlepage
72 @contents
73
74 @node Top
75 @top Introduction
76
77 @cindex version
78 This brief manual contains documentation for the @sc{gnu} binary
79 utilities
80 @ifset VERSION_PACKAGE
81 @value{VERSION_PACKAGE}
82 @end ifset
83 version @value{VERSION}:
84
85 @iftex
86 @table @code
87 @item ar
88 Create, modify, and extract from archives
89
90 @item nm
91 List symbols from object files
92
93 @item objcopy
94 Copy and translate object files
95
96 @item objdump
97 Display information from object files
98
99 @item ranlib
100 Generate index to archive contents
101
102 @item readelf
103 Display the contents of ELF format files.
104
105 @item size
106 List file section sizes and total size
107
108 @item strings
109 List printable strings from files
110
111 @item strip
112 Discard symbols
113
114 @item elfedit
115 Update the ELF header of ELF files.
116
117 @item c++filt
118 Demangle encoded C++ symbols (on MS-DOS, this program is named
119 @code{cxxfilt})
120
121 @item addr2line
122 Convert addresses into file names and line numbers
123
124 @item nlmconv
125 Convert object code into a Netware Loadable Module
126
127 @item windres
128 Manipulate Windows resources
129
130 @item windmc
131 Generator for Windows message resources
132
133 @item dlltool
134 Create the files needed to build and use Dynamic Link Libraries
135 @end table
136 @end iftex
137
138 This document is distributed under the terms of the GNU Free
139 Documentation License version 1.3. A copy of the license is included
140 in the section entitled ``GNU Free Documentation License''.
141
142 @menu
143 * ar:: Create, modify, and extract from archives
144 * nm:: List symbols from object files
145 * objcopy:: Copy and translate object files
146 * objdump:: Display information from object files
147 * ranlib:: Generate index to archive contents
148 * size:: List section sizes and total size
149 * strings:: List printable strings from files
150 * strip:: Discard symbols
151 * c++filt:: Filter to demangle encoded C++ symbols
152 * cxxfilt: c++filt. MS-DOS name for c++filt
153 * addr2line:: Convert addresses to file and line
154 * nlmconv:: Converts object code into an NLM
155 * windmc:: Generator for Windows message resources
156 * windres:: Manipulate Windows resources
157 * dlltool:: Create files needed to build and use DLLs
158 * readelf:: Display the contents of ELF format files
159 * elfedit:: Update the ELF header of ELF files
160 * Common Options:: Command-line options for all utilities
161 * Selecting the Target System:: How these utilities determine the target
162 * Reporting Bugs:: Reporting Bugs
163 * GNU Free Documentation License:: GNU Free Documentation License
164 * Binutils Index:: Binutils Index
165 @end menu
166
167 @node ar
168 @chapter ar
169
170 @kindex ar
171 @cindex archives
172 @cindex collections of files
173
174 @c man title ar create, modify, and extract from archives
175
176 @smallexample
177 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
178 ar -M [ <mri-script ]
179 @end smallexample
180
181 @c man begin DESCRIPTION ar
182
183 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
184 archives. An @dfn{archive} is a single file holding a collection of
185 other files in a structure that makes it possible to retrieve
186 the original individual files (called @dfn{members} of the archive).
187
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
190 extraction.
191
192 @cindex name length
193 @sc{gnu} @command{ar} can maintain archives whose members have names of any
194 length; however, depending on how @command{ar} is configured on your
195 system, a limit on member-name length may be imposed for compatibility
196 with archive formats maintained with other tools. If it exists, the
197 limit is often 15 characters (typical of formats related to a.out) or 16
198 characters (typical of formats related to coff).
199
200 @cindex libraries
201 @command{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
203 subroutines.
204
205 @cindex symbol index
206 @command{ar} creates an index to the symbols defined in relocatable
207 object modules in the archive when you specify the modifier @samp{s}.
208 Once created, this index is updated in the archive whenever @command{ar}
209 makes a change to its contents (save for the @samp{q} update operation).
210 An archive with such an index speeds up linking to the library, and
211 allows routines in the library to call each other without regard to
212 their placement in the archive.
213
214 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215 table. If an archive lacks the table, another form of @command{ar} called
216 @command{ranlib} can be used to add just the table.
217
218 @cindex thin archives
219 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
220 which contains a symbol index and references to the original copies
221 of the member files of the archive. This is useful for building
222 libraries for use within a local build tree, where the relocatable
223 objects are expected to remain available, and copying the contents of
224 each object would only waste time and space.
225
226 An archive can either be @emph{thin} or it can be normal. It cannot
227 be both at the same time. Once an archive is created its format
228 cannot be changed without first deleting it and then creating a new
229 archive in its place.
230
231 Thin archives are also @emph{flattened}, so that adding one thin
232 archive to another thin archive does not nest it, as would happen with
233 a normal archive. Instead the elements of the first archive are added
234 individually to the second archive.
235
236 The paths to the elements of the archive are stored relative to the
237 archive itself. For security reasons absolute paths and paths with a
238 @code{/../} component are not allowed.
239
240 @cindex compatibility, @command{ar}
241 @cindex @command{ar} compatibility
242 @sc{gnu} @command{ar} is designed to be compatible with two different
243 facilities. You can control its activity using command-line options,
244 like the different varieties of @command{ar} on Unix systems; or, if you
245 specify the single command-line option @option{-M}, you can control it
246 with a script supplied via standard input, like the MRI ``librarian''
247 program.
248
249 @c man end
250
251 @menu
252 * ar cmdline:: Controlling @command{ar} on the command line
253 * ar scripts:: Controlling @command{ar} with a script
254 @end menu
255
256 @page
257 @node ar cmdline
258 @section Controlling @command{ar} on the Command Line
259
260 @smallexample
261 @c man begin SYNOPSIS ar
262 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{}]
263 @c man end
264 @end smallexample
265
266 @cindex Unix compatibility, @command{ar}
267 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
268 arguments to execute: one keyletter specifying the @emph{operation}
269 (optionally accompanied by other keyletters specifying
270 @emph{modifiers}), and the archive name to act on.
271
272 Most operations can also accept further @var{member} arguments,
273 specifying particular files to operate on.
274
275 @c man begin OPTIONS ar
276
277 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
278 flags @var{mod} in any order, within the first command-line argument.
279
280 If you wish, you may begin the first command-line argument with a
281 dash.
282
283 @cindex operations on archive
284 The @var{p} keyletter specifies what operation to execute; it may be
285 any of the following, but you must specify only one of them:
286
287 @table @samp
288 @item d
289 @cindex deleting from archive
290 @emph{Delete} modules from the archive. Specify the names of modules to
291 be deleted as @var{member}@dots{}; the archive is untouched if you
292 specify no files to delete.
293
294 If you specify the @samp{v} modifier, @command{ar} lists each module
295 as it is deleted.
296
297 @item m
298 @cindex moving in archive
299 Use this operation to @emph{move} members in an archive.
300
301 The ordering of members in an archive can make a difference in how
302 programs are linked using the library, if a symbol is defined in more
303 than one member.
304
305 If no modifiers are used with @code{m}, any members you name in the
306 @var{member} arguments are moved to the @emph{end} of the archive;
307 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
308 specified place instead.
309
310 @item p
311 @cindex printing from archive
312 @emph{Print} the specified members of the archive, to the standard
313 output file. If the @samp{v} modifier is specified, show the member
314 name before copying its contents to standard output.
315
316 If you specify no @var{member} arguments, all the files in the archive are
317 printed.
318
319 @item q
320 @cindex quick append to archive
321 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
322 @var{archive}, without checking for replacement.
323
324 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
325 operation; new members are always placed at the end of the archive.
326
327 The modifier @samp{v} makes @command{ar} list each file as it is appended.
328
329 Since the point of this operation is speed, implementations of
330 @command{ar} have the option of not updating the archive's symbol
331 table if one exists. Too many different systems however assume that
332 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
333 rebuild the table even with a quick append.
334
335 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
336 synonym for @samp{r} - replacing already existing files in the
337 archive and appending new ones at the end.
338
339 @item r
340 @cindex replacement in archive
341 Insert the files @var{member}@dots{} into @var{archive} (with
342 @emph{replacement}). This operation differs from @samp{q} in that any
343 previously existing members are deleted if their names match those being
344 added.
345
346 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
347 displays an error message, and leaves undisturbed any existing members
348 of the archive matching that name.
349
350 By default, new members are added at the end of the file; but you may
351 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
352 placement relative to some existing member.
353
354 The modifier @samp{v} used with this operation elicits a line of
355 output for each file inserted, along with one of the letters @samp{a} or
356 @samp{r} to indicate whether the file was appended (no old member
357 deleted) or replaced.
358
359 @item s
360 @cindex ranlib
361 Add an index to the archive, or update it if it already exists. Note
362 this command is an exception to the rule that there can only be one
363 command letter, as it is possible to use it as either a command or a
364 modifier. In either case it does the same thing.
365
366 @item t
367 @cindex contents of archive
368 Display a @emph{table} listing the contents of @var{archive}, or those
369 of the files listed in @var{member}@dots{} that are present in the
370 archive. Normally only the member name is shown; if you also want to
371 see the modes (permissions), timestamp, owner, group, and size, you can
372 request that by also specifying the @samp{v} modifier.
373
374 If you do not specify a @var{member}, all files in the archive
375 are listed.
376
377 @cindex repeated names in archive
378 @cindex name duplication in archive
379 If there is more than one file with the same name (say, @samp{fie}) in
380 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
381 first instance; to see them all, you must ask for a complete
382 listing---in our example, @samp{ar t b.a}.
383 @c WRS only; per Gumby, this is implementation-dependent, and in a more
384 @c recent case in fact works the other way.
385
386 @item x
387 @cindex extract from archive
388 @emph{Extract} members (named @var{member}) from the archive. You can
389 use the @samp{v} modifier with this operation, to request that
390 @command{ar} list each name as it extracts it.
391
392 If you do not specify a @var{member}, all files in the archive
393 are extracted.
394
395 Files cannot be extracted from a thin archive.
396
397 @item --help
398 Displays the list of command line options supported by @command{ar}
399 and then exits.
400
401 @item --version
402 Displays the version information of @command{ar} and then exits.
403
404 @end table
405
406 A number of modifiers (@var{mod}) may immediately follow the @var{p}
407 keyletter, to specify variations on an operation's behavior:
408
409 @table @samp
410 @item a
411 @cindex relative placement in archive
412 Add new files @emph{after} an existing member of the
413 archive. If you use the modifier @samp{a}, the name of an existing archive
414 member must be present as the @var{relpos} argument, before the
415 @var{archive} specification.
416
417 @item b
418 Add new files @emph{before} an existing member of the
419 archive. If you use the modifier @samp{b}, the name of an existing archive
420 member must be present as the @var{relpos} argument, before the
421 @var{archive} specification. (same as @samp{i}).
422
423 @item c
424 @cindex creating archives
425 @emph{Create} the archive. The specified @var{archive} is always
426 created if it did not exist, when you request an update. But a warning is
427 issued unless you specify in advance that you expect to create it, by
428 using this modifier.
429
430 @item D
431 @cindex deterministic archives
432 @kindex --enable-deterministic-archives
433 Operate in @emph{deterministic} mode. When adding files and the archive
434 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
435 for all files. When this option is used, if @command{ar} is used with
436 identical options and identical input files, multiple runs will create
437 identical output files regardless of the input files' owners, groups,
438 file modes, or modification times.
439
440 If @file{binutils} was configured with
441 @option{--enable-deterministic-archives}, then this mode is on by default.
442 It can be disabled with the @samp{U} modifier, below.
443
444 @item f
445 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
446 names of any length. This will cause it to create archives which are
447 not compatible with the native @command{ar} program on some systems. If
448 this is a concern, the @samp{f} modifier may be used to truncate file
449 names when putting them in the archive.
450
451 @item i
452 Insert new files @emph{before} an existing member of the
453 archive. If you use the modifier @samp{i}, the name of an existing archive
454 member must be present as the @var{relpos} argument, before the
455 @var{archive} specification. (same as @samp{b}).
456
457 @item l
458 This modifier is accepted but not used.
459 @c whaffor ar l modifier??? presumably compat; with
460 @c what???---doc@@cygnus.com, 25jan91
461
462 @item N
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
466
467 @item o
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
472
473 @item P
474 Use the full path name when matching names in the archive. @sc{gnu}
475 @command{ar} can not create an archive with a full path name (such archives
476 are not POSIX complaint), but other archive creators can. This option
477 will cause @sc{gnu} @command{ar} to match file names using a complete path
478 name, which can be convenient when extracting a single file from an
479 archive created by another tool.
480
481 @item s
482 @cindex writing archive index
483 Write an object-file index into the archive, or update an existing one,
484 even if no other change is made to the archive. You may use this modifier
485 flag either with any operation, or alone. Running @samp{ar s} on an
486 archive is equivalent to running @samp{ranlib} on it.
487
488 @item S
489 @cindex not writing archive index
490 Do not generate an archive symbol table. This can speed up building a
491 large library in several steps. The resulting archive can not be used
492 with the linker. In order to build a symbol table, you must omit the
493 @samp{S} modifier on the last execution of @samp{ar}, or you must run
494 @samp{ranlib} on the archive.
495
496 @item T
497 @cindex creating thin archive
498 Make the specified @var{archive} a @emph{thin} archive. If it already
499 exists and is a regular archive, the existing members must be present
500 in the same directory as @var{archive}.
501
502 @item u
503 @cindex updating an archive
504 Normally, @samp{ar r}@dots{} inserts all files
505 listed into the archive. If you would like to insert @emph{only} those
506 of the files you list that are newer than existing members of the same
507 names, use this modifier. The @samp{u} modifier is allowed only for the
508 operation @samp{r} (replace). In particular, the combination @samp{qu} is
509 not allowed, since checking the timestamps would lose any speed
510 advantage from the operation @samp{q}.
511
512 @item U
513 @cindex deterministic archives
514 @kindex --enable-deterministic-archives
515 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
516 of the @samp{D} modifier, above: added files and the archive index will
517 get their actual UID, GID, timestamp, and file mode values.
518
519 This is the default unless @file{binutils} was configured with
520 @option{--enable-deterministic-archives}.
521
522 @item v
523 This modifier requests the @emph{verbose} version of an operation. Many
524 operations display additional information, such as filenames processed,
525 when the modifier @samp{v} is appended.
526
527 @item V
528 This modifier shows the version number of @command{ar}.
529 @end table
530
531 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
532 compatibility with AIX. The behaviour produced by this option is the
533 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
534 @samp{-X} options; in particular, it does not support @option{-X32}
535 which is the default for AIX @command{ar}.
536
537 The optional command line switch @option{--plugin} @var{name} causes
538 @command{ar} to load the plugin called @var{name} which adds support
539 for more file formats. This option is only available if the toolchain
540 has been built with plugin support enabled.
541
542 The optional command line switch @option{--target} @var{bfdname}
543 specifies that the archive members are in an object code format
544 different from your system's default format. See
545 @xref{Target Selection}, for more information.
546
547 @c man end
548
549 @ignore
550 @c man begin SEEALSO ar
551 nm(1), ranlib(1), and the Info entries for @file{binutils}.
552 @c man end
553 @end ignore
554
555 @node ar scripts
556 @section Controlling @command{ar} with a Script
557
558 @smallexample
559 ar -M [ <@var{script} ]
560 @end smallexample
561
562 @cindex MRI compatibility, @command{ar}
563 @cindex scripts, @command{ar}
564 If you use the single command-line option @samp{-M} with @command{ar}, you
565 can control its operation with a rudimentary command language. This
566 form of @command{ar} operates interactively if standard input is coming
567 directly from a terminal. During interactive use, @command{ar} prompts for
568 input (the prompt is @samp{AR >}), and continues executing even after
569 errors. If you redirect standard input to a script file, no prompts are
570 issued, and @command{ar} abandons execution (with a nonzero exit code)
571 on any error.
572
573 The @command{ar} command language is @emph{not} designed to be equivalent
574 to the command-line options; in fact, it provides somewhat less control
575 over archives. The only purpose of the command language is to ease the
576 transition to @sc{gnu} @command{ar} for developers who already have scripts
577 written for the MRI ``librarian'' program.
578
579 The syntax for the @command{ar} command language is straightforward:
580 @itemize @bullet
581 @item
582 commands are recognized in upper or lower case; for example, @code{LIST}
583 is the same as @code{list}. In the following descriptions, commands are
584 shown in upper case for clarity.
585
586 @item
587 a single command may appear on each line; it is the first word on the
588 line.
589
590 @item
591 empty lines are allowed, and have no effect.
592
593 @item
594 comments are allowed; text after either of the characters @samp{*}
595 or @samp{;} is ignored.
596
597 @item
598 Whenever you use a list of names as part of the argument to an @command{ar}
599 command, you can separate the individual names with either commas or
600 blanks. Commas are shown in the explanations below, for clarity.
601
602 @item
603 @samp{+} is used as a line continuation character; if @samp{+} appears
604 at the end of a line, the text on the following line is considered part
605 of the current command.
606 @end itemize
607
608 Here are the commands you can use in @command{ar} scripts, or when using
609 @command{ar} interactively. Three of them have special significance:
610
611 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
612 a temporary file required for most of the other commands.
613
614 @code{SAVE} commits the changes so far specified by the script. Prior
615 to @code{SAVE}, commands affect only the temporary copy of the current
616 archive.
617
618 @table @code
619 @item ADDLIB @var{archive}
620 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
621 Add all the contents of @var{archive} (or, if specified, each named
622 @var{module} from @var{archive}) to the current archive.
623
624 Requires prior use of @code{OPEN} or @code{CREATE}.
625
626 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
627 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
628 @c else like "ar q..."
629 Add each named @var{member} as a module in the current archive.
630
631 Requires prior use of @code{OPEN} or @code{CREATE}.
632
633 @item CLEAR
634 Discard the contents of the current archive, canceling the effect of
635 any operations since the last @code{SAVE}. May be executed (with no
636 effect) even if no current archive is specified.
637
638 @item CREATE @var{archive}
639 Creates an archive, and makes it the current archive (required for many
640 other commands). The new archive is created with a temporary name; it
641 is not actually saved as @var{archive} until you use @code{SAVE}.
642 You can overwrite existing archives; similarly, the contents of any
643 existing file named @var{archive} will not be destroyed until @code{SAVE}.
644
645 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
646 Delete each listed @var{module} from the current archive; equivalent to
647 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
648
649 Requires prior use of @code{OPEN} or @code{CREATE}.
650
651 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
652 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
653 List each named @var{module} present in @var{archive}. The separate
654 command @code{VERBOSE} specifies the form of the output: when verbose
655 output is off, output is like that of @samp{ar -t @var{archive}
656 @var{module}@dots{}}. When verbose output is on, the listing is like
657 @samp{ar -tv @var{archive} @var{module}@dots{}}.
658
659 Output normally goes to the standard output stream; however, if you
660 specify @var{outputfile} as a final argument, @command{ar} directs the
661 output to that file.
662
663 @item END
664 Exit from @command{ar}, with a @code{0} exit code to indicate successful
665 completion. This command does not save the output file; if you have
666 changed the current archive since the last @code{SAVE} command, those
667 changes are lost.
668
669 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
670 Extract each named @var{module} from the current archive, writing them
671 into the current directory as separate files. Equivalent to @samp{ar -x
672 @var{archive} @var{module}@dots{}}.
673
674 Requires prior use of @code{OPEN} or @code{CREATE}.
675
676 @ignore
677 @c FIXME Tokens but no commands???
678 @item FULLDIR
679
680 @item HELP
681 @end ignore
682
683 @item LIST
684 Display full contents of the current archive, in ``verbose'' style
685 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
686 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
687 enhancement, rather than present for MRI compatibility.)
688
689 Requires prior use of @code{OPEN} or @code{CREATE}.
690
691 @item OPEN @var{archive}
692 Opens an existing archive for use as the current archive (required for
693 many other commands). Any changes as the result of subsequent commands
694 will not actually affect @var{archive} until you next use @code{SAVE}.
695
696 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
697 In the current archive, replace each existing @var{module} (named in
698 the @code{REPLACE} arguments) from files in the current working directory.
699 To execute this command without errors, both the file, and the module in
700 the current archive, must exist.
701
702 Requires prior use of @code{OPEN} or @code{CREATE}.
703
704 @item VERBOSE
705 Toggle an internal flag governing the output from @code{DIRECTORY}.
706 When the flag is on, @code{DIRECTORY} output matches output from
707 @samp{ar -tv }@dots{}.
708
709 @item SAVE
710 Commit your changes to the current archive, and actually save it as a
711 file with the name specified in the last @code{CREATE} or @code{OPEN}
712 command.
713
714 Requires prior use of @code{OPEN} or @code{CREATE}.
715
716 @end table
717
718 @iftex
719 @node ld
720 @chapter ld
721 @cindex linker
722 @kindex ld
723 The @sc{gnu} linker @command{ld} is now described in a separate manual.
724 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
725 @end iftex
726
727 @node nm
728 @chapter nm
729 @cindex symbols
730 @kindex nm
731
732 @c man title nm list symbols from object files
733
734 @smallexample
735 @c man begin SYNOPSIS nm
736 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
737 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
738 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
739 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
740 [@option{-l}|@option{--line-numbers}] [@option{-n}|@option{-v}|@option{--numeric-sort}]
741 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
742 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
743 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
744 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
745 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
746 [@option{--plugin} @var{name}] [@option{--size-sort}] [@option{--special-syms}]
747 [@option{--synthetic}] [@option{--target=}@var{bfdname}]
748 [@var{objfile}@dots{}]
749 @c man end
750 @end smallexample
751
752 @c man begin DESCRIPTION nm
753 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
754 If no object files are listed as arguments, @command{nm} assumes the file
755 @file{a.out}.
756
757 For each symbol, @command{nm} shows:
758
759 @itemize @bullet
760 @item
761 The symbol value, in the radix selected by options (see below), or
762 hexadecimal by default.
763
764 @item
765 The symbol type. At least the following types are used; others are, as
766 well, depending on the object file format. If lowercase, the symbol is
767 usually local; if uppercase, the symbol is global (external). There
768 are however a few lowercase symbols that are shown for special global
769 symbols (@code{u}, @code{v} and @code{w}).
770
771 @c Some more detail on exactly what these symbol types are used for
772 @c would be nice.
773 @table @code
774 @item A
775 The symbol's value is absolute, and will not be changed by further
776 linking.
777
778 @item B
779 @itemx b
780 The symbol is in the uninitialized data section (known as BSS).
781
782 @item C
783 The symbol is common. Common symbols are uninitialized data. When
784 linking, multiple common symbols may appear with the same name. If the
785 symbol is defined anywhere, the common symbols are treated as undefined
786 references.
787 @ifclear man
788 For more details on common symbols, see the discussion of
789 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
790 @end ifclear
791
792 @item D
793 @itemx d
794 The symbol is in the initialized data section.
795
796 @item G
797 @itemx g
798 The symbol is in an initialized data section for small objects. Some
799 object file formats permit more efficient access to small data objects,
800 such as a global int variable as opposed to a large global array.
801
802 @item i
803 For PE format files this indicates that the symbol is in a section
804 specific to the implementation of DLLs. For ELF format files this
805 indicates that the symbol is an indirect function. This is a GNU
806 extension to the standard set of ELF symbol types. It indicates a
807 symbol which if referenced by a relocation does not evaluate to its
808 address, but instead must be invoked at runtime. The runtime
809 execution will then return the value to be used in the relocation.
810
811 @item I
812 The symbol is an indirect reference to another symbol.
813
814 @item N
815 The symbol is a debugging symbol.
816
817 @item p
818 The symbols is in a stack unwind section.
819
820 @item R
821 @itemx r
822 The symbol is in a read only data section.
823
824 @item S
825 @itemx s
826 The symbol is in an uninitialized data section for small objects.
827
828 @item T
829 @itemx t
830 The symbol is in the text (code) section.
831
832 @item U
833 The symbol is undefined.
834
835 @item u
836 The symbol is a unique global symbol. This is a GNU extension to the
837 standard set of ELF symbol bindings. For such a symbol the dynamic linker
838 will make sure that in the entire process there is just one symbol with
839 this name and type in use.
840
841 @item V
842 @itemx v
843 The symbol is a weak object. When a weak defined symbol is linked with
844 a normal defined symbol, the normal defined symbol is used with no error.
845 When a weak undefined symbol is linked and the symbol is not defined,
846 the value of the weak symbol becomes zero with no error. On some
847 systems, uppercase indicates that a default value has been specified.
848
849 @item W
850 @itemx w
851 The symbol is a weak symbol that has not been specifically tagged as a
852 weak object symbol. When a weak defined symbol is linked with a normal
853 defined symbol, the normal defined symbol is used with no error.
854 When a weak undefined symbol is linked and the symbol is not defined,
855 the value of the symbol is determined in a system-specific manner without
856 error. On some systems, uppercase indicates that a default value has been
857 specified.
858
859 @item -
860 The symbol is a stabs symbol in an a.out object file. In this case, the
861 next values printed are the stabs other field, the stabs desc field, and
862 the stab type. Stabs symbols are used to hold debugging information.
863
864 @item ?
865 The symbol type is unknown, or object file format specific.
866 @end table
867
868 @item
869 The symbol name.
870 @end itemize
871
872 @c man end
873
874 @c man begin OPTIONS nm
875 The long and short forms of options, shown here as alternatives, are
876 equivalent.
877
878 @table @env
879 @item -A
880 @itemx -o
881 @itemx --print-file-name
882 @cindex input file name
883 @cindex file name
884 @cindex source file name
885 Precede each symbol by the name of the input file (or archive member)
886 in which it was found, rather than identifying the input file once only,
887 before all of its symbols.
888
889 @item -a
890 @itemx --debug-syms
891 @cindex debugging symbols
892 Display all symbols, even debugger-only symbols; normally these are not
893 listed.
894
895 @item -B
896 @cindex @command{nm} format
897 @cindex @command{nm} compatibility
898 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
899
900 @item -C
901 @itemx --demangle[=@var{style}]
902 @cindex demangling in nm
903 Decode (@dfn{demangle}) low-level symbol names into user-level names.
904 Besides removing any initial underscore prepended by the system, this
905 makes C++ function names readable. Different compilers have different
906 mangling styles. The optional demangling style argument can be used to
907 choose an appropriate demangling style for your compiler. @xref{c++filt},
908 for more information on demangling.
909
910 @item --no-demangle
911 Do not demangle low-level symbol names. This is the default.
912
913 @item -D
914 @itemx --dynamic
915 @cindex dynamic symbols
916 Display the dynamic symbols rather than the normal symbols. This is
917 only meaningful for dynamic objects, such as certain types of shared
918 libraries.
919
920 @item -f @var{format}
921 @itemx --format=@var{format}
922 @cindex @command{nm} format
923 @cindex @command{nm} compatibility
924 Use the output format @var{format}, which can be @code{bsd},
925 @code{sysv}, or @code{posix}. The default is @code{bsd}.
926 Only the first character of @var{format} is significant; it can be
927 either upper or lower case.
928
929 @item -g
930 @itemx --extern-only
931 @cindex external symbols
932 Display only external symbols.
933
934 @item -h
935 @itemx --help
936 Show a summary of the options to @command{nm} and exit.
937
938 @item -l
939 @itemx --line-numbers
940 @cindex symbol line numbers
941 For each symbol, use debugging information to try to find a filename and
942 line number. For a defined symbol, look for the line number of the
943 address of the symbol. For an undefined symbol, look for the line
944 number of a relocation entry which refers to the symbol. If line number
945 information can be found, print it after the other symbol information.
946
947 @item -n
948 @itemx -v
949 @itemx --numeric-sort
950 Sort symbols numerically by their addresses, rather than alphabetically
951 by their names.
952
953 @item -p
954 @itemx --no-sort
955 @cindex sorting symbols
956 Do not bother to sort the symbols in any order; print them in the order
957 encountered.
958
959 @item -P
960 @itemx --portability
961 Use the POSIX.2 standard output format instead of the default format.
962 Equivalent to @samp{-f posix}.
963
964 @item -r
965 @itemx --reverse-sort
966 Reverse the order of the sort (whether numeric or alphabetic); let the
967 last come first.
968
969 @item -S
970 @itemx --print-size
971 Print both value and size of defined symbols for the @code{bsd} output style.
972 This option has no effect for object formats that do not record symbol
973 sizes, unless @samp{--size-sort} is also used in which case a
974 calculated size is displayed.
975
976 @item -s
977 @itemx --print-armap
978 @cindex symbol index, listing
979 When listing symbols from archive members, include the index: a mapping
980 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
981 contain definitions for which names.
982
983 @item -t @var{radix}
984 @itemx --radix=@var{radix}
985 Use @var{radix} as the radix for printing the symbol values. It must be
986 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
987
988 @item -u
989 @itemx --undefined-only
990 @cindex external symbols
991 @cindex undefined symbols
992 Display only undefined symbols (those external to each object file).
993
994 @item -V
995 @itemx --version
996 Show the version number of @command{nm} and exit.
997
998 @item -X
999 This option is ignored for compatibility with the AIX version of
1000 @command{nm}. It takes one parameter which must be the string
1001 @option{32_64}. The default mode of AIX @command{nm} corresponds
1002 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1003
1004 @item --defined-only
1005 @cindex external symbols
1006 @cindex undefined symbols
1007 Display only defined symbols for each object file.
1008
1009 @item --plugin @var{name}
1010 @cindex load plugin
1011 Load the plugin called @var{name} to add support for extra target
1012 types. This option is only available if the toolchain has been built
1013 with plugin support enabled.
1014
1015 @item --size-sort
1016 Sort symbols by size. The size is computed as the difference between
1017 the value of the symbol and the value of the symbol with the next higher
1018 value. If the @code{bsd} output format is used the size of the symbol
1019 is printed, rather than the value, and @samp{-S} must be used in order
1020 both size and value to be printed.
1021
1022 @item --special-syms
1023 Display symbols which have a target-specific special meaning. These
1024 symbols are usually used by the target for some special processing and
1025 are not normally helpful when included in the normal symbol lists.
1026 For example for ARM targets this option would skip the mapping symbols
1027 used to mark transitions between ARM code, THUMB code and data.
1028
1029 @item --synthetic
1030 Include synthetic symbols in the output. These are special symbols
1031 created by the linker for various purposes. They are not shown by
1032 default since they are not part of the binary's original source code.
1033
1034 @item --target=@var{bfdname}
1035 @cindex object code format
1036 Specify an object code format other than your system's default format.
1037 @xref{Target Selection}, for more information.
1038
1039 @end table
1040
1041 @c man end
1042
1043 @ignore
1044 @c man begin SEEALSO nm
1045 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1046 @c man end
1047 @end ignore
1048
1049 @node objcopy
1050 @chapter objcopy
1051
1052 @c man title objcopy copy and translate object files
1053
1054 @smallexample
1055 @c man begin SYNOPSIS objcopy
1056 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1057 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1058 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1059 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1060 [@option{-S}|@option{--strip-all}]
1061 [@option{-g}|@option{--strip-debug}]
1062 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1063 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1064 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1065 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1066 [@option{--localize-hidden}]
1067 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1068 [@option{--globalize-symbol=}@var{symbolname}]
1069 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1070 [@option{-w}|@option{--wildcard}]
1071 [@option{-x}|@option{--discard-all}]
1072 [@option{-X}|@option{--discard-locals}]
1073 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1074 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1075 [@option{--interleave-width=}@var{width}]
1076 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1077 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1078 [@option{-p}|@option{--preserve-dates}]
1079 [@option{-D}|@option{--enable-deterministic-archives}]
1080 [@option{-U}|@option{--disable-deterministic-archives}]
1081 [@option{--debugging}]
1082 [@option{--gap-fill=}@var{val}]
1083 [@option{--pad-to=}@var{address}]
1084 [@option{--set-start=}@var{val}]
1085 [@option{--adjust-start=}@var{incr}]
1086 [@option{--change-addresses=}@var{incr}]
1087 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1088 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1089 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1090 [@option{--change-warnings}] [@option{--no-change-warnings}]
1091 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1092 [@option{--add-section} @var{sectionname}=@var{filename}]
1093 [@option{--dump-section} @var{sectionname}=@var{filename}]
1094 [@option{--update-section} @var{sectionname}=@var{filename}]
1095 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1096 [@option{--long-section-names} @{enable,disable,keep@}]
1097 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1098 [@option{--reverse-bytes=}@var{num}]
1099 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1100 [@option{--redefine-sym} @var{old}=@var{new}]
1101 [@option{--redefine-syms=}@var{filename}]
1102 [@option{--weaken}]
1103 [@option{--keep-symbols=}@var{filename}]
1104 [@option{--strip-symbols=}@var{filename}]
1105 [@option{--strip-unneeded-symbols=}@var{filename}]
1106 [@option{--keep-global-symbols=}@var{filename}]
1107 [@option{--localize-symbols=}@var{filename}]
1108 [@option{--globalize-symbols=}@var{filename}]
1109 [@option{--weaken-symbols=}@var{filename}]
1110 [@option{--alt-machine-code=}@var{index}]
1111 [@option{--prefix-symbols=}@var{string}]
1112 [@option{--prefix-sections=}@var{string}]
1113 [@option{--prefix-alloc-sections=}@var{string}]
1114 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1115 [@option{--keep-file-symbols}]
1116 [@option{--only-keep-debug}]
1117 [@option{--strip-dwo}]
1118 [@option{--extract-dwo}]
1119 [@option{--extract-symbol}]
1120 [@option{--writable-text}]
1121 [@option{--readonly-text}]
1122 [@option{--pure}]
1123 [@option{--impure}]
1124 [@option{--file-alignment=}@var{num}]
1125 [@option{--heap=}@var{size}]
1126 [@option{--image-base=}@var{address}]
1127 [@option{--section-alignment=}@var{num}]
1128 [@option{--stack=}@var{size}]
1129 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1130 [@option{--compress-debug-sections}]
1131 [@option{--decompress-debug-sections}]
1132 [@option{--dwarf-depth=@var{n}}]
1133 [@option{--dwarf-start=@var{n}}]
1134 [@option{-v}|@option{--verbose}]
1135 [@option{-V}|@option{--version}]
1136 [@option{--help}] [@option{--info}]
1137 @var{infile} [@var{outfile}]
1138 @c man end
1139 @end smallexample
1140
1141 @c man begin DESCRIPTION objcopy
1142 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1143 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1144 read and write the object files. It can write the destination object
1145 file in a format different from that of the source object file. The
1146 exact behavior of @command{objcopy} is controlled by command-line options.
1147 Note that @command{objcopy} should be able to copy a fully linked file
1148 between any two formats. However, copying a relocatable object file
1149 between any two formats may not work as expected.
1150
1151 @command{objcopy} creates temporary files to do its translations and
1152 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1153 translation work; it has access to all the formats described in @sc{bfd}
1154 and thus is able to recognize most formats without being told
1155 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1156
1157 @command{objcopy} can be used to generate S-records by using an output
1158 target of @samp{srec} (e.g., use @samp{-O srec}).
1159
1160 @command{objcopy} can be used to generate a raw binary file by using an
1161 output target of @samp{binary} (e.g., use @option{-O binary}). When
1162 @command{objcopy} generates a raw binary file, it will essentially produce
1163 a memory dump of the contents of the input object file. All symbols and
1164 relocation information will be discarded. The memory dump will start at
1165 the load address of the lowest section copied into the output file.
1166
1167 When generating an S-record or a raw binary file, it may be helpful to
1168 use @option{-S} to remove sections containing debugging information. In
1169 some cases @option{-R} will be useful to remove sections which contain
1170 information that is not needed by the binary file.
1171
1172 Note---@command{objcopy} is not able to change the endianness of its input
1173 files. If the input format has an endianness (some formats do not),
1174 @command{objcopy} can only copy the inputs into file formats that have the
1175 same endianness or which have no endianness (e.g., @samp{srec}).
1176 (However, see the @option{--reverse-bytes} option.)
1177
1178 @c man end
1179
1180 @c man begin OPTIONS objcopy
1181
1182 @table @env
1183 @item @var{infile}
1184 @itemx @var{outfile}
1185 The input and output files, respectively.
1186 If you do not specify @var{outfile}, @command{objcopy} creates a
1187 temporary file and destructively renames the result with
1188 the name of @var{infile}.
1189
1190 @item -I @var{bfdname}
1191 @itemx --input-target=@var{bfdname}
1192 Consider the source file's object format to be @var{bfdname}, rather than
1193 attempting to deduce it. @xref{Target Selection}, for more information.
1194
1195 @item -O @var{bfdname}
1196 @itemx --output-target=@var{bfdname}
1197 Write the output file using the object format @var{bfdname}.
1198 @xref{Target Selection}, for more information.
1199
1200 @item -F @var{bfdname}
1201 @itemx --target=@var{bfdname}
1202 Use @var{bfdname} as the object format for both the input and the output
1203 file; i.e., simply transfer data from source to destination with no
1204 translation. @xref{Target Selection}, for more information.
1205
1206 @item -B @var{bfdarch}
1207 @itemx --binary-architecture=@var{bfdarch}
1208 Useful when transforming a architecture-less input file into an object file.
1209 In this case the output architecture can be set to @var{bfdarch}. This
1210 option will be ignored if the input file has a known @var{bfdarch}. You
1211 can access this binary data inside a program by referencing the special
1212 symbols that are created by the conversion process. These symbols are
1213 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1214 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1215 an object file and then access it in your code using these symbols.
1216
1217 @item -j @var{sectionpattern}
1218 @itemx --only-section=@var{sectionpattern}
1219 Copy only the indicated sections from the input file to the output file.
1220 This option may be given more than once. Note that using this option
1221 inappropriately may make the output file unusable. Wildcard
1222 characters are accepted in @var{sectionpattern}.
1223
1224 @item -R @var{sectionpattern}
1225 @itemx --remove-section=@var{sectionpattern}
1226 Remove any section matching @var{sectionpattern} from the output file.
1227 This option may be given more than once. Note that using this option
1228 inappropriately may make the output file unusable. Wildcard
1229 characters are accepted in @var{sectionpattern}. Using both the
1230 @option{-j} and @option{-R} options together results in undefined
1231 behaviour.
1232
1233 @item -S
1234 @itemx --strip-all
1235 Do not copy relocation and symbol information from the source file.
1236
1237 @item -g
1238 @itemx --strip-debug
1239 Do not copy debugging symbols or sections from the source file.
1240
1241 @item --strip-unneeded
1242 Strip all symbols that are not needed for relocation processing.
1243
1244 @item -K @var{symbolname}
1245 @itemx --keep-symbol=@var{symbolname}
1246 When stripping symbols, keep symbol @var{symbolname} even if it would
1247 normally be stripped. This option may be given more than once.
1248
1249 @item -N @var{symbolname}
1250 @itemx --strip-symbol=@var{symbolname}
1251 Do not copy symbol @var{symbolname} from the source file. This option
1252 may be given more than once.
1253
1254 @item --strip-unneeded-symbol=@var{symbolname}
1255 Do not copy symbol @var{symbolname} from the source file unless it is needed
1256 by a relocation. This option may be given more than once.
1257
1258 @item -G @var{symbolname}
1259 @itemx --keep-global-symbol=@var{symbolname}
1260 Keep only symbol @var{symbolname} global. Make all other symbols local
1261 to the file, so that they are not visible externally. This option may
1262 be given more than once.
1263
1264 @item --localize-hidden
1265 In an ELF object, mark all symbols that have hidden or internal visibility
1266 as local. This option applies on top of symbol-specific localization options
1267 such as @option{-L}.
1268
1269 @item -L @var{symbolname}
1270 @itemx --localize-symbol=@var{symbolname}
1271 Make symbol @var{symbolname} local to the file, so that it is not
1272 visible externally. This option may be given more than once.
1273
1274 @item -W @var{symbolname}
1275 @itemx --weaken-symbol=@var{symbolname}
1276 Make symbol @var{symbolname} weak. This option may be given more than once.
1277
1278 @item --globalize-symbol=@var{symbolname}
1279 Give symbol @var{symbolname} global scoping so that it is visible
1280 outside of the file in which it is defined. This option may be given
1281 more than once.
1282
1283 @item -w
1284 @itemx --wildcard
1285 Permit regular expressions in @var{symbolname}s used in other command
1286 line options. The question mark (?), asterisk (*), backslash (\) and
1287 square brackets ([]) operators can be used anywhere in the symbol
1288 name. If the first character of the symbol name is the exclamation
1289 point (!) then the sense of the switch is reversed for that symbol.
1290 For example:
1291
1292 @smallexample
1293 -w -W !foo -W fo*
1294 @end smallexample
1295
1296 would cause objcopy to weaken all symbols that start with ``fo''
1297 except for the symbol ``foo''.
1298
1299 @item -x
1300 @itemx --discard-all
1301 Do not copy non-global symbols from the source file.
1302 @c FIXME any reason to prefer "non-global" to "local" here?
1303
1304 @item -X
1305 @itemx --discard-locals
1306 Do not copy compiler-generated local symbols.
1307 (These usually start with @samp{L} or @samp{.}.)
1308
1309 @item -b @var{byte}
1310 @itemx --byte=@var{byte}
1311 If interleaving has been enabled via the @option{--interleave} option
1312 then start the range of bytes to keep at the @var{byte}th byte.
1313 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1314 @var{breadth} is the value given by the @option{--interleave} option.
1315
1316 @item -i [@var{breadth}]
1317 @itemx --interleave[=@var{breadth}]
1318 Only copy a range out of every @var{breadth} bytes. (Header data is
1319 not affected). Select which byte in the range begins the copy with
1320 the @option{--byte} option. Select the width of the range with the
1321 @option{--interleave-width} option.
1322
1323 This option is useful for creating files to program @sc{rom}. It is
1324 typically used with an @code{srec} output target. Note that
1325 @command{objcopy} will complain if you do not specify the
1326 @option{--byte} option as well.
1327
1328 The default interleave breadth is 4, so with @option{--byte} set to 0,
1329 @command{objcopy} would copy the first byte out of every four bytes
1330 from the input to the output.
1331
1332 @item --interleave-width=@var{width}
1333 When used with the @option{--interleave} option, copy @var{width}
1334 bytes at a time. The start of the range of bytes to be copied is set
1335 by the @option{--byte} option, and the extent of the range is set with
1336 the @option{--interleave} option.
1337
1338 The default value for this option is 1. The value of @var{width} plus
1339 the @var{byte} value set by the @option{--byte} option must not exceed
1340 the interleave breadth set by the @option{--interleave} option.
1341
1342 This option can be used to create images for two 16-bit flashes interleaved
1343 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1344 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1345 commands. If the input was '12345678' then the outputs would be
1346 '1256' and '3478' respectively.
1347
1348 @item -p
1349 @itemx --preserve-dates
1350 Set the access and modification dates of the output file to be the same
1351 as those of the input file.
1352
1353 @item -D
1354 @itemx --enable-deterministic-archives
1355 @cindex deterministic archives
1356 @kindex --enable-deterministic-archives
1357 Operate in @emph{deterministic} mode. When copying archive members
1358 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1359 and use consistent file modes for all files.
1360
1361 If @file{binutils} was configured with
1362 @option{--enable-deterministic-archives}, then this mode is on by default.
1363 It can be disabled with the @samp{-U} option, below.
1364
1365 @item -U
1366 @itemx --disable-deterministic-archives
1367 @cindex deterministic archives
1368 @kindex --enable-deterministic-archives
1369 Do @emph{not} operate in @emph{deterministic} mode. This is the
1370 inverse of the @option{-D} option, above: when copying archive members
1371 and writing the archive index, use their actual UID, GID, timestamp,
1372 and file mode values.
1373
1374 This is the default unless @file{binutils} was configured with
1375 @option{--enable-deterministic-archives}.
1376
1377 @item --debugging
1378 Convert debugging information, if possible. This is not the default
1379 because only certain debugging formats are supported, and the
1380 conversion process can be time consuming.
1381
1382 @item --gap-fill @var{val}
1383 Fill gaps between sections with @var{val}. This operation applies to
1384 the @emph{load address} (LMA) of the sections. It is done by increasing
1385 the size of the section with the lower address, and filling in the extra
1386 space created with @var{val}.
1387
1388 @item --pad-to @var{address}
1389 Pad the output file up to the load address @var{address}. This is
1390 done by increasing the size of the last section. The extra space is
1391 filled in with the value specified by @option{--gap-fill} (default zero).
1392
1393 @item --set-start @var{val}
1394 Set the start address of the new file to @var{val}. Not all object file
1395 formats support setting the start address.
1396
1397 @item --change-start @var{incr}
1398 @itemx --adjust-start @var{incr}
1399 @cindex changing start address
1400 Change the start address by adding @var{incr}. Not all object file
1401 formats support setting the start address.
1402
1403 @item --change-addresses @var{incr}
1404 @itemx --adjust-vma @var{incr}
1405 @cindex changing object addresses
1406 Change the VMA and LMA addresses of all sections, as well as the start
1407 address, by adding @var{incr}. Some object file formats do not permit
1408 section addresses to be changed arbitrarily. Note that this does not
1409 relocate the sections; if the program expects sections to be loaded at a
1410 certain address, and this option is used to change the sections such
1411 that they are loaded at a different address, the program may fail.
1412
1413 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1414 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1415 @cindex changing section address
1416 Set or change both the VMA address and the LMA address of any section
1417 matching @var{sectionpattern}. If @samp{=} is used, the section
1418 address is set to @var{val}. Otherwise, @var{val} is added to or
1419 subtracted from the section address. See the comments under
1420 @option{--change-addresses}, above. If @var{sectionpattern} does not
1421 match any sections in the input file, a warning will be issued, unless
1422 @option{--no-change-warnings} is used.
1423
1424 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1425 @cindex changing section LMA
1426 Set or change the LMA address of any sections matching
1427 @var{sectionpattern}. The LMA address is the address where the
1428 section will be loaded into memory at program load time. Normally
1429 this is the same as the VMA address, which is the address of the
1430 section at program run time, but on some systems, especially those
1431 where a program is held in ROM, the two can be different. If @samp{=}
1432 is used, the section address is set to @var{val}. Otherwise,
1433 @var{val} is added to or subtracted from the section address. See the
1434 comments under @option{--change-addresses}, above. If
1435 @var{sectionpattern} does not match any sections in the input file, a
1436 warning will be issued, unless @option{--no-change-warnings} is used.
1437
1438 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1439 @cindex changing section VMA
1440 Set or change the VMA address of any section matching
1441 @var{sectionpattern}. The VMA address is the address where the
1442 section will be located once the program has started executing.
1443 Normally this is the same as the LMA address, which is the address
1444 where the section will be loaded into memory, but on some systems,
1445 especially those where a program is held in ROM, the two can be
1446 different. If @samp{=} is used, the section address is set to
1447 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1448 section address. See the comments under @option{--change-addresses},
1449 above. If @var{sectionpattern} does not match any sections in the
1450 input file, a warning will be issued, unless
1451 @option{--no-change-warnings} is used.
1452
1453 @item --change-warnings
1454 @itemx --adjust-warnings
1455 If @option{--change-section-address} or @option{--change-section-lma} or
1456 @option{--change-section-vma} is used, and the section pattern does not
1457 match any sections, issue a warning. This is the default.
1458
1459 @item --no-change-warnings
1460 @itemx --no-adjust-warnings
1461 Do not issue a warning if @option{--change-section-address} or
1462 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1463 if the section pattern does not match any sections.
1464
1465 @item --set-section-flags @var{sectionpattern}=@var{flags}
1466 Set the flags for any sections matching @var{sectionpattern}. The
1467 @var{flags} argument is a comma separated string of flag names. The
1468 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1469 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1470 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1471 for a section which does not have contents, but it is not meaningful
1472 to clear the @samp{contents} flag of a section which does have
1473 contents--just remove the section instead. Not all flags are
1474 meaningful for all object file formats.
1475
1476 @item --add-section @var{sectionname}=@var{filename}
1477 Add a new section named @var{sectionname} while copying the file. The
1478 contents of the new section are taken from the file @var{filename}. The
1479 size of the section will be the size of the file. This option only
1480 works on file formats which can support sections with arbitrary names.
1481 Note - it may be necessary to use the @option{--set-section-flags}
1482 option to set the attributes of the newly created section.
1483
1484 @item --dump-section @var{sectionname}=@var{filename}
1485 Place the contents of section named @var{sectionname} into the file
1486 @var{filename}, overwriting any contents that may have been there
1487 previously. This option is the inverse of @option{--add-section}.
1488 This option is similar to the @option{--only-section} option except
1489 that it does not create a formatted file, it just dumps the contents
1490 as raw binary data, without applying any relocations. The option can
1491 be specified more than once.
1492
1493 @item --update-section @var{sectionname}=@var{filename}
1494 Replace the existing contents of a section named @var{sectionname}
1495 with the contents of file @var{filename}. The size of the section
1496 will be adjusted to the size of the file. The section flags for
1497 @var{sectionname} will be unchanged. For ELF format files the section
1498 to segment mapping will also remain unchanged, something which is not
1499 possible using @option{--remove-section} followed by
1500 @option{--add-section}. The option can be specified more than once.
1501
1502 Note - it is possible to use @option{--rename-section} and
1503 @option{--update-section} to both update and rename a section from one
1504 command line. In this case, pass the original section name to
1505 @option{--update-section}, and the original and new section names to
1506 @option{--rename-section}.
1507
1508 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1509 Rename a section from @var{oldname} to @var{newname}, optionally
1510 changing the section's flags to @var{flags} in the process. This has
1511 the advantage over usng a linker script to perform the rename in that
1512 the output stays as an object file and does not become a linked
1513 executable.
1514
1515 This option is particularly helpful when the input format is binary,
1516 since this will always create a section called .data. If for example,
1517 you wanted instead to create a section called .rodata containing binary
1518 data you could use the following command line to achieve it:
1519
1520 @smallexample
1521 objcopy -I binary -O <output_format> -B <architecture> \
1522 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1523 <input_binary_file> <output_object_file>
1524 @end smallexample
1525
1526 @item --long-section-names @{enable,disable,keep@}
1527 Controls the handling of long section names when processing @code{COFF}
1528 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1529 is to preserve long section names if any are present in the input file.
1530 The @samp{enable} and @samp{disable} options forcibly enable or disable
1531 the use of long section names in the output object; when @samp{disable}
1532 is in effect, any long section names in the input object will be truncated.
1533 The @samp{enable} option will only emit long section names if any are
1534 present in the inputs; this is mostly the same as @samp{keep}, but it
1535 is left undefined whether the @samp{enable} option might force the
1536 creation of an empty string table in the output file.
1537
1538 @item --change-leading-char
1539 Some object file formats use special characters at the start of
1540 symbols. The most common such character is underscore, which compilers
1541 often add before every symbol. This option tells @command{objcopy} to
1542 change the leading character of every symbol when it converts between
1543 object file formats. If the object file formats use the same leading
1544 character, this option has no effect. Otherwise, it will add a
1545 character, or remove a character, or change a character, as
1546 appropriate.
1547
1548 @item --remove-leading-char
1549 If the first character of a global symbol is a special symbol leading
1550 character used by the object file format, remove the character. The
1551 most common symbol leading character is underscore. This option will
1552 remove a leading underscore from all global symbols. This can be useful
1553 if you want to link together objects of different file formats with
1554 different conventions for symbol names. This is different from
1555 @option{--change-leading-char} because it always changes the symbol name
1556 when appropriate, regardless of the object file format of the output
1557 file.
1558
1559 @item --reverse-bytes=@var{num}
1560 Reverse the bytes in a section with output contents. A section length must
1561 be evenly divisible by the value given in order for the swap to be able to
1562 take place. Reversing takes place before the interleaving is performed.
1563
1564 This option is used typically in generating ROM images for problematic
1565 target systems. For example, on some target boards, the 32-bit words
1566 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1567 regardless of the CPU byte order. Depending on the programming model, the
1568 endianness of the ROM may need to be modified.
1569
1570 Consider a simple file with a section containing the following eight
1571 bytes: @code{12345678}.
1572
1573 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1574 output file would be ordered @code{21436587}.
1575
1576 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1577 output file would be ordered @code{43218765}.
1578
1579 By using @samp{--reverse-bytes=2} for the above example, followed by
1580 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1581 output file would be ordered @code{34127856}.
1582
1583 @item --srec-len=@var{ival}
1584 Meaningful only for srec output. Set the maximum length of the Srecords
1585 being produced to @var{ival}. This length covers both address, data and
1586 crc fields.
1587
1588 @item --srec-forceS3
1589 Meaningful only for srec output. Avoid generation of S1/S2 records,
1590 creating S3-only record format.
1591
1592 @item --redefine-sym @var{old}=@var{new}
1593 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1594 when one is trying link two things together for which you have no
1595 source, and there are name collisions.
1596
1597 @item --redefine-syms=@var{filename}
1598 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1599 listed in the file @var{filename}. @var{filename} is simply a flat file,
1600 with one symbol pair per line. Line comments may be introduced by the hash
1601 character. This option may be given more than once.
1602
1603 @item --weaken
1604 Change all global symbols in the file to be weak. This can be useful
1605 when building an object which will be linked against other objects using
1606 the @option{-R} option to the linker. This option is only effective when
1607 using an object file format which supports weak symbols.
1608
1609 @item --keep-symbols=@var{filename}
1610 Apply @option{--keep-symbol} option to each symbol listed in the file
1611 @var{filename}. @var{filename} is simply a flat file, with one symbol
1612 name per line. Line comments may be introduced by the hash character.
1613 This option may be given more than once.
1614
1615 @item --strip-symbols=@var{filename}
1616 Apply @option{--strip-symbol} option to each symbol listed in the file
1617 @var{filename}. @var{filename} is simply a flat file, with one symbol
1618 name per line. Line comments may be introduced by the hash character.
1619 This option may be given more than once.
1620
1621 @item --strip-unneeded-symbols=@var{filename}
1622 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1623 the file @var{filename}. @var{filename} is simply a flat file, with one
1624 symbol name per line. Line comments may be introduced by the hash
1625 character. This option may be given more than once.
1626
1627 @item --keep-global-symbols=@var{filename}
1628 Apply @option{--keep-global-symbol} option to each symbol listed in the
1629 file @var{filename}. @var{filename} is simply a flat file, with one
1630 symbol name per line. Line comments may be introduced by the hash
1631 character. This option may be given more than once.
1632
1633 @item --localize-symbols=@var{filename}
1634 Apply @option{--localize-symbol} option to each symbol listed in the file
1635 @var{filename}. @var{filename} is simply a flat file, with one symbol
1636 name per line. Line comments may be introduced by the hash character.
1637 This option may be given more than once.
1638
1639 @item --globalize-symbols=@var{filename}
1640 Apply @option{--globalize-symbol} option to each symbol listed in the file
1641 @var{filename}. @var{filename} is simply a flat file, with one symbol
1642 name per line. Line comments may be introduced by the hash character.
1643 This option may be given more than once.
1644
1645 @item --weaken-symbols=@var{filename}
1646 Apply @option{--weaken-symbol} option to each symbol listed in the file
1647 @var{filename}. @var{filename} is simply a flat file, with one symbol
1648 name per line. Line comments may be introduced by the hash character.
1649 This option may be given more than once.
1650
1651 @item --alt-machine-code=@var{index}
1652 If the output architecture has alternate machine codes, use the
1653 @var{index}th code instead of the default one. This is useful in case
1654 a machine is assigned an official code and the tool-chain adopts the
1655 new code, but other applications still depend on the original code
1656 being used. For ELF based architectures if the @var{index}
1657 alternative does not exist then the value is treated as an absolute
1658 number to be stored in the e_machine field of the ELF header.
1659
1660 @item --writable-text
1661 Mark the output text as writable. This option isn't meaningful for all
1662 object file formats.
1663
1664 @item --readonly-text
1665 Make the output text write protected. This option isn't meaningful for all
1666 object file formats.
1667
1668 @item --pure
1669 Mark the output file as demand paged. This option isn't meaningful for all
1670 object file formats.
1671
1672 @item --impure
1673 Mark the output file as impure. This option isn't meaningful for all
1674 object file formats.
1675
1676 @item --prefix-symbols=@var{string}
1677 Prefix all symbols in the output file with @var{string}.
1678
1679 @item --prefix-sections=@var{string}
1680 Prefix all section names in the output file with @var{string}.
1681
1682 @item --prefix-alloc-sections=@var{string}
1683 Prefix all the names of all allocated sections in the output file with
1684 @var{string}.
1685
1686 @item --add-gnu-debuglink=@var{path-to-file}
1687 Creates a .gnu_debuglink section which contains a reference to
1688 @var{path-to-file} and adds it to the output file. Note: the file at
1689 @var{path-to-file} must exist. Part of the process of adding the
1690 .gnu_debuglink section involves embedding a checksum of the contents
1691 of the debug info file into the section.
1692
1693 If the debug info file is built in one location but it is going to be
1694 installed at a later time into a different location then do not use
1695 the path to the installed location. The @option{--add-gnu-debuglink}
1696 option will fail because the installed file does not exist yet.
1697 Instead put the debug info file in the current directory and use the
1698 @option{--add-gnu-debuglink} option without any directory components,
1699 like this:
1700
1701 @smallexample
1702 objcopy --add-gnu-debuglink=foo.debug
1703 @end smallexample
1704
1705 At debug time the debugger will attempt to look for the separate debug
1706 info file in a set of known locations. The exact set of these
1707 locations varies depending upon the distribution being used, but it
1708 typically includes:
1709
1710 @table @code
1711
1712 @item * The same directory as the executable.
1713
1714 @item * A sub-directory of the directory containing the executable
1715 called .debug
1716
1717 @item * A global debug directory such as /usr/lib/debug.
1718 @end table
1719
1720 As long as the debug info file has been installed into one of these
1721 locations before the debugger is run everything should work
1722 correctly.
1723
1724 @item --keep-file-symbols
1725 When stripping a file, perhaps with @option{--strip-debug} or
1726 @option{--strip-unneeded}, retain any symbols specifying source file names,
1727 which would otherwise get stripped.
1728
1729 @item --only-keep-debug
1730 Strip a file, removing contents of any sections that would not be
1731 stripped by @option{--strip-debug} and leaving the debugging sections
1732 intact. In ELF files, this preserves all note sections in the output.
1733
1734 The intention is that this option will be used in conjunction with
1735 @option{--add-gnu-debuglink} to create a two part executable. One a
1736 stripped binary which will occupy less space in RAM and in a
1737 distribution and the second a debugging information file which is only
1738 needed if debugging abilities are required. The suggested procedure
1739 to create these files is as follows:
1740
1741 @enumerate
1742 @item Link the executable as normal. Assuming that is is called
1743 @code{foo} then...
1744 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1745 create a file containing the debugging info.
1746 @item Run @code{objcopy --strip-debug foo} to create a
1747 stripped executable.
1748 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1749 to add a link to the debugging info into the stripped executable.
1750 @end enumerate
1751
1752 Note---the choice of @code{.dbg} as an extension for the debug info
1753 file is arbitrary. Also the @code{--only-keep-debug} step is
1754 optional. You could instead do this:
1755
1756 @enumerate
1757 @item Link the executable as normal.
1758 @item Copy @code{foo} to @code{foo.full}
1759 @item Run @code{objcopy --strip-debug foo}
1760 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1761 @end enumerate
1762
1763 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1764 full executable. It does not have to be a file created by the
1765 @option{--only-keep-debug} switch.
1766
1767 Note---this switch is only intended for use on fully linked files. It
1768 does not make sense to use it on object files where the debugging
1769 information may be incomplete. Besides the gnu_debuglink feature
1770 currently only supports the presence of one filename containing
1771 debugging information, not multiple filenames on a one-per-object-file
1772 basis.
1773
1774 @item --strip-dwo
1775 Remove the contents of all DWARF .dwo sections, leaving the
1776 remaining debugging sections and all symbols intact.
1777 This option is intended for use by the compiler as part of
1778 the @option{-gsplit-dwarf} option, which splits debug information
1779 between the .o file and a separate .dwo file. The compiler
1780 generates all debug information in the same file, then uses
1781 the @option{--extract-dwo} option to copy the .dwo sections to
1782 the .dwo file, then the @option{--strip-dwo} option to remove
1783 those sections from the original .o file.
1784
1785 @item --extract-dwo
1786 Extract the contents of all DWARF .dwo sections. See the
1787 @option{--strip-dwo} option for more information.
1788
1789 @item --file-alignment @var{num}
1790 Specify the file alignment. Sections in the file will always begin at
1791 file offsets which are multiples of this number. This defaults to
1792 512.
1793 [This option is specific to PE targets.]
1794
1795 @item --heap @var{reserve}
1796 @itemx --heap @var{reserve},@var{commit}
1797 Specify the number of bytes of memory to reserve (and optionally commit)
1798 to be used as heap for this program.
1799 [This option is specific to PE targets.]
1800
1801 @item --image-base @var{value}
1802 Use @var{value} as the base address of your program or dll. This is
1803 the lowest memory location that will be used when your program or dll
1804 is loaded. To reduce the need to relocate and improve performance of
1805 your dlls, each should have a unique base address and not overlap any
1806 other dlls. The default is 0x400000 for executables, and 0x10000000
1807 for dlls.
1808 [This option is specific to PE targets.]
1809
1810 @item --section-alignment @var{num}
1811 Sets the section alignment. Sections in memory will always begin at
1812 addresses which are a multiple of this number. Defaults to 0x1000.
1813 [This option is specific to PE targets.]
1814
1815 @item --stack @var{reserve}
1816 @itemx --stack @var{reserve},@var{commit}
1817 Specify the number of bytes of memory to reserve (and optionally commit)
1818 to be used as stack for this program.
1819 [This option is specific to PE targets.]
1820
1821 @item --subsystem @var{which}
1822 @itemx --subsystem @var{which}:@var{major}
1823 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1824 Specifies the subsystem under which your program will execute. The
1825 legal values for @var{which} are @code{native}, @code{windows},
1826 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1827 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1828 the subsystem version also. Numeric values are also accepted for
1829 @var{which}.
1830 [This option is specific to PE targets.]
1831
1832 @item --extract-symbol
1833 Keep the file's section flags and symbols but remove all section data.
1834 Specifically, the option:
1835
1836 @itemize
1837 @item removes the contents of all sections;
1838 @item sets the size of every section to zero; and
1839 @item sets the file's start address to zero.
1840 @end itemize
1841
1842 This option is used to build a @file{.sym} file for a VxWorks kernel.
1843 It can also be a useful way of reducing the size of a @option{--just-symbols}
1844 linker input file.
1845
1846 @item --compress-debug-sections
1847 Compress DWARF debug sections using zlib. The debug sections are
1848 renamed to begin with @samp{.zdebug} instead of @samp{.debug}. Note -
1849 if compression would actually make a section @emph{larger} then it is
1850 not compressed or renamed.
1851
1852 @item --decompress-debug-sections
1853 Decompress DWARF debug sections using zlib. The original section
1854 names of the compressed sections are restored.
1855
1856 @item -V
1857 @itemx --version
1858 Show the version number of @command{objcopy}.
1859
1860 @item -v
1861 @itemx --verbose
1862 Verbose output: list all object files modified. In the case of
1863 archives, @samp{objcopy -V} lists all members of the archive.
1864
1865 @item --help
1866 Show a summary of the options to @command{objcopy}.
1867
1868 @item --info
1869 Display a list showing all architectures and object formats available.
1870 @end table
1871
1872 @c man end
1873
1874 @ignore
1875 @c man begin SEEALSO objcopy
1876 ld(1), objdump(1), and the Info entries for @file{binutils}.
1877 @c man end
1878 @end ignore
1879
1880 @node objdump
1881 @chapter objdump
1882
1883 @cindex object file information
1884 @kindex objdump
1885
1886 @c man title objdump display information from object files.
1887
1888 @smallexample
1889 @c man begin SYNOPSIS objdump
1890 objdump [@option{-a}|@option{--archive-headers}]
1891 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1892 [@option{-C}|@option{--demangle}[=@var{style}] ]
1893 [@option{-d}|@option{--disassemble}]
1894 [@option{-D}|@option{--disassemble-all}]
1895 [@option{-z}|@option{--disassemble-zeroes}]
1896 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1897 [@option{-f}|@option{--file-headers}]
1898 [@option{-F}|@option{--file-offsets}]
1899 [@option{--file-start-context}]
1900 [@option{-g}|@option{--debugging}]
1901 [@option{-e}|@option{--debugging-tags}]
1902 [@option{-h}|@option{--section-headers}|@option{--headers}]
1903 [@option{-i}|@option{--info}]
1904 [@option{-j} @var{section}|@option{--section=}@var{section}]
1905 [@option{-l}|@option{--line-numbers}]
1906 [@option{-S}|@option{--source}]
1907 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1908 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1909 [@option{-p}|@option{--private-headers}]
1910 [@option{-P} @var{options}|@option{--private=}@var{options}]
1911 [@option{-r}|@option{--reloc}]
1912 [@option{-R}|@option{--dynamic-reloc}]
1913 [@option{-s}|@option{--full-contents}]
1914 [@option{-W[lLiaprmfFsoRt]}|
1915 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames]
1916 [=aranges,=macro,=frames,=frames-interp,=str,=loc]
1917 [=Ranges,=pubtypes,=trace_info,=trace_abbrev]
1918 [=trace_aranges,=gdb_index]
1919 [@option{-G}|@option{--stabs}]
1920 [@option{-t}|@option{--syms}]
1921 [@option{-T}|@option{--dynamic-syms}]
1922 [@option{-x}|@option{--all-headers}]
1923 [@option{-w}|@option{--wide}]
1924 [@option{--start-address=}@var{address}]
1925 [@option{--stop-address=}@var{address}]
1926 [@option{--prefix-addresses}]
1927 [@option{--[no-]show-raw-insn}]
1928 [@option{--adjust-vma=}@var{offset}]
1929 [@option{--special-syms}]
1930 [@option{--prefix=}@var{prefix}]
1931 [@option{--prefix-strip=}@var{level}]
1932 [@option{--insn-width=}@var{width}]
1933 [@option{-V}|@option{--version}]
1934 [@option{-H}|@option{--help}]
1935 @var{objfile}@dots{}
1936 @c man end
1937 @end smallexample
1938
1939 @c man begin DESCRIPTION objdump
1940
1941 @command{objdump} displays information about one or more object files.
1942 The options control what particular information to display. This
1943 information is mostly useful to programmers who are working on the
1944 compilation tools, as opposed to programmers who just want their
1945 program to compile and work.
1946
1947 @var{objfile}@dots{} are the object files to be examined. When you
1948 specify archives, @command{objdump} shows information on each of the member
1949 object files.
1950
1951 @c man end
1952
1953 @c man begin OPTIONS objdump
1954
1955 The long and short forms of options, shown here as alternatives, are
1956 equivalent. At least one option from the list
1957 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1958
1959 @table @env
1960 @item -a
1961 @itemx --archive-header
1962 @cindex archive headers
1963 If any of the @var{objfile} files are archives, display the archive
1964 header information (in a format similar to @samp{ls -l}). Besides the
1965 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1966 the object file format of each archive member.
1967
1968 @item --adjust-vma=@var{offset}
1969 @cindex section addresses in objdump
1970 @cindex VMA in objdump
1971 When dumping information, first add @var{offset} to all the section
1972 addresses. This is useful if the section addresses do not correspond to
1973 the symbol table, which can happen when putting sections at particular
1974 addresses when using a format which can not represent section addresses,
1975 such as a.out.
1976
1977 @item -b @var{bfdname}
1978 @itemx --target=@var{bfdname}
1979 @cindex object code format
1980 Specify that the object-code format for the object files is
1981 @var{bfdname}. This option may not be necessary; @var{objdump} can
1982 automatically recognize many formats.
1983
1984 For example,
1985 @example
1986 objdump -b oasys -m vax -h fu.o
1987 @end example
1988 @noindent
1989 displays summary information from the section headers (@option{-h}) of
1990 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1991 file in the format produced by Oasys compilers. You can list the
1992 formats available with the @option{-i} option.
1993 @xref{Target Selection}, for more information.
1994
1995 @item -C
1996 @itemx --demangle[=@var{style}]
1997 @cindex demangling in objdump
1998 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1999 Besides removing any initial underscore prepended by the system, this
2000 makes C++ function names readable. Different compilers have different
2001 mangling styles. The optional demangling style argument can be used to
2002 choose an appropriate demangling style for your compiler. @xref{c++filt},
2003 for more information on demangling.
2004
2005 @item -g
2006 @itemx --debugging
2007 Display debugging information. This attempts to parse STABS and IEEE
2008 debugging format information stored in the file and print it out using
2009 a C like syntax. If neither of these formats are found this option
2010 falls back on the @option{-W} option to print any DWARF information in
2011 the file.
2012
2013 @item -e
2014 @itemx --debugging-tags
2015 Like @option{-g}, but the information is generated in a format compatible
2016 with ctags tool.
2017
2018 @item -d
2019 @itemx --disassemble
2020 @cindex disassembling object code
2021 @cindex machine instructions
2022 Display the assembler mnemonics for the machine instructions from
2023 @var{objfile}. This option only disassembles those sections which are
2024 expected to contain instructions.
2025
2026 @item -D
2027 @itemx --disassemble-all
2028 Like @option{-d}, but disassemble the contents of all sections, not just
2029 those expected to contain instructions.
2030
2031 If the target is an ARM architecture this switch also has the effect
2032 of forcing the disassembler to decode pieces of data found in code
2033 sections as if they were instructions.
2034
2035 @item --prefix-addresses
2036 When disassembling, print the complete address on each line. This is
2037 the older disassembly format.
2038
2039 @item -EB
2040 @itemx -EL
2041 @itemx --endian=@{big|little@}
2042 @cindex endianness
2043 @cindex disassembly endianness
2044 Specify the endianness of the object files. This only affects
2045 disassembly. This can be useful when disassembling a file format which
2046 does not describe endianness information, such as S-records.
2047
2048 @item -f
2049 @itemx --file-headers
2050 @cindex object file header
2051 Display summary information from the overall header of
2052 each of the @var{objfile} files.
2053
2054 @item -F
2055 @itemx --file-offsets
2056 @cindex object file offsets
2057 When disassembling sections, whenever a symbol is displayed, also
2058 display the file offset of the region of data that is about to be
2059 dumped. If zeroes are being skipped, then when disassembly resumes,
2060 tell the user how many zeroes were skipped and the file offset of the
2061 location from where the disassembly resumes. When dumping sections,
2062 display the file offset of the location from where the dump starts.
2063
2064 @item --file-start-context
2065 @cindex source code context
2066 Specify that when displaying interlisted source code/disassembly
2067 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2068 context to the start of the file.
2069
2070 @item -h
2071 @itemx --section-headers
2072 @itemx --headers
2073 @cindex section headers
2074 Display summary information from the section headers of the
2075 object file.
2076
2077 File segments may be relocated to nonstandard addresses, for example by
2078 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2079 @command{ld}. However, some object file formats, such as a.out, do not
2080 store the starting address of the file segments. In those situations,
2081 although @command{ld} relocates the sections correctly, using @samp{objdump
2082 -h} to list the file section headers cannot show the correct addresses.
2083 Instead, it shows the usual addresses, which are implicit for the
2084 target.
2085
2086 @item -H
2087 @itemx --help
2088 Print a summary of the options to @command{objdump} and exit.
2089
2090 @item -i
2091 @itemx --info
2092 @cindex architectures available
2093 @cindex object formats available
2094 Display a list showing all architectures and object formats available
2095 for specification with @option{-b} or @option{-m}.
2096
2097 @item -j @var{name}
2098 @itemx --section=@var{name}
2099 @cindex section information
2100 Display information only for section @var{name}.
2101
2102 @item -l
2103 @itemx --line-numbers
2104 @cindex source filenames for object files
2105 Label the display (using debugging information) with the filename and
2106 source line numbers corresponding to the object code or relocs shown.
2107 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2108
2109 @item -m @var{machine}
2110 @itemx --architecture=@var{machine}
2111 @cindex architecture
2112 @cindex disassembly architecture
2113 Specify the architecture to use when disassembling object files. This
2114 can be useful when disassembling object files which do not describe
2115 architecture information, such as S-records. You can list the available
2116 architectures with the @option{-i} option.
2117
2118 If the target is an ARM architecture then this switch has an
2119 additional effect. It restricts the disassembly to only those
2120 instructions supported by the architecture specified by @var{machine}.
2121 If it is necessary to use this switch because the input file does not
2122 contain any architecture information, but it is also desired to
2123 disassemble all the instructions use @option{-marm}.
2124
2125 @item -M @var{options}
2126 @itemx --disassembler-options=@var{options}
2127 Pass target specific information to the disassembler. Only supported on
2128 some targets. If it is necessary to specify more than one
2129 disassembler option then multiple @option{-M} options can be used or
2130 can be placed together into a comma separated list.
2131
2132 If the target is an ARM architecture then this switch can be used to
2133 select which register name set is used during disassembler. Specifying
2134 @option{-M reg-names-std} (the default) will select the register names as
2135 used in ARM's instruction set documentation, but with register 13 called
2136 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2137 @option{-M reg-names-apcs} will select the name set used by the ARM
2138 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2139 just use @samp{r} followed by the register number.
2140
2141 There are also two variants on the APCS register naming scheme enabled
2142 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2143 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2144 with the normal register names or the special register names).
2145
2146 This option can also be used for ARM architectures to force the
2147 disassembler to interpret all instructions as Thumb instructions by
2148 using the switch @option{--disassembler-options=force-thumb}. This can be
2149 useful when attempting to disassemble thumb code produced by other
2150 compilers.
2151
2152 For the x86, some of the options duplicate functions of the @option{-m}
2153 switch, but allow finer grained control. Multiple selections from the
2154 following may be specified as a comma separated string.
2155 @table @code
2156 @item x86-64
2157 @itemx i386
2158 @itemx i8086
2159 Select disassembly for the given architecture.
2160
2161 @item intel
2162 @itemx att
2163 Select between intel syntax mode and AT&T syntax mode.
2164
2165 @item intel-mnemonic
2166 @itemx att-mnemonic
2167 Select between intel mnemonic mode and AT&T mnemonic mode.
2168 Note: @code{intel-mnemonic} implies @code{intel} and
2169 @code{att-mnemonic} implies @code{att}.
2170
2171 @item addr64
2172 @itemx addr32
2173 @itemx addr16
2174 @itemx data32
2175 @itemx data16
2176 Specify the default address size and operand size. These four options
2177 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2178 appear later in the option string.
2179
2180 @item suffix
2181 When in AT&T mode, instructs the disassembler to print a mnemonic
2182 suffix even when the suffix could be inferred by the operands.
2183 @end table
2184
2185 For PowerPC, @option{booke} controls the disassembly of BookE
2186 instructions. @option{32} and @option{64} select PowerPC and
2187 PowerPC64 disassembly, respectively. @option{e300} selects
2188 disassembly for the e300 family. @option{440} selects disassembly for
2189 the PowerPC 440. @option{ppcps} selects disassembly for the paired
2190 single instructions of the PPC750CL.
2191
2192 For MIPS, this option controls the printing of instruction mnemonic
2193 names and register names in disassembled instructions. Multiple
2194 selections from the following may be specified as a comma separated
2195 string, and invalid options are ignored:
2196
2197 @table @code
2198 @item no-aliases
2199 Print the 'raw' instruction mnemonic instead of some pseudo
2200 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2201 'sll' instead of 'nop', etc.
2202
2203 @item msa
2204 Disassemble MSA instructions.
2205
2206 @item virt
2207 Disassemble the virtualization ASE instructions.
2208
2209 @item xpa
2210 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2211
2212 @item gpr-names=@var{ABI}
2213 Print GPR (general-purpose register) names as appropriate
2214 for the specified ABI. By default, GPR names are selected according to
2215 the ABI of the binary being disassembled.
2216
2217 @item fpr-names=@var{ABI}
2218 Print FPR (floating-point register) names as
2219 appropriate for the specified ABI. By default, FPR numbers are printed
2220 rather than names.
2221
2222 @item cp0-names=@var{ARCH}
2223 Print CP0 (system control coprocessor; coprocessor 0) register names
2224 as appropriate for the CPU or architecture specified by
2225 @var{ARCH}. By default, CP0 register names are selected according to
2226 the architecture and CPU of the binary being disassembled.
2227
2228 @item hwr-names=@var{ARCH}
2229 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2230 as appropriate for the CPU or architecture specified by
2231 @var{ARCH}. By default, HWR names are selected according to
2232 the architecture and CPU of the binary being disassembled.
2233
2234 @item reg-names=@var{ABI}
2235 Print GPR and FPR names as appropriate for the selected ABI.
2236
2237 @item reg-names=@var{ARCH}
2238 Print CPU-specific register names (CP0 register and HWR names)
2239 as appropriate for the selected CPU or architecture.
2240 @end table
2241
2242 For any of the options listed above, @var{ABI} or
2243 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2244 rather than names, for the selected types of registers.
2245 You can list the available values of @var{ABI} and @var{ARCH} using
2246 the @option{--help} option.
2247
2248 For VAX, you can specify function entry addresses with @option{-M
2249 entry:0xf00ba}. You can use this multiple times to properly
2250 disassemble VAX binary files that don't contain symbol tables (like
2251 ROM dumps). In these cases, the function entry mask would otherwise
2252 be decoded as VAX instructions, which would probably lead the rest
2253 of the function being wrongly disassembled.
2254
2255 @item -p
2256 @itemx --private-headers
2257 Print information that is specific to the object file format. The exact
2258 information printed depends upon the object file format. For some
2259 object file formats, no additional information is printed.
2260
2261 @item -P @var{options}
2262 @itemx --private=@var{options}
2263 Print information that is specific to the object file format. The
2264 argument @var{options} is a comma separated list that depends on the
2265 format (the lists of options is displayed with the help).
2266
2267 For XCOFF, the available options are:
2268 @table @code
2269 @item header
2270 @item aout
2271 @item sections
2272 @item syms
2273 @item relocs
2274 @item lineno,
2275 @item loader
2276 @item except
2277 @item typchk
2278 @item traceback
2279 @item toc
2280 @item ldinfo
2281 @end table
2282
2283 Not all object formats support this option. In particular the ELF
2284 format does not use it.
2285
2286 @item -r
2287 @itemx --reloc
2288 @cindex relocation entries, in object file
2289 Print the relocation entries of the file. If used with @option{-d} or
2290 @option{-D}, the relocations are printed interspersed with the
2291 disassembly.
2292
2293 @item -R
2294 @itemx --dynamic-reloc
2295 @cindex dynamic relocation entries, in object file
2296 Print the dynamic relocation entries of the file. This is only
2297 meaningful for dynamic objects, such as certain types of shared
2298 libraries. As for @option{-r}, if used with @option{-d} or
2299 @option{-D}, the relocations are printed interspersed with the
2300 disassembly.
2301
2302 @item -s
2303 @itemx --full-contents
2304 @cindex sections, full contents
2305 @cindex object file sections
2306 Display the full contents of any sections requested. By default all
2307 non-empty sections are displayed.
2308
2309 @item -S
2310 @itemx --source
2311 @cindex source disassembly
2312 @cindex disassembly, with source
2313 Display source code intermixed with disassembly, if possible. Implies
2314 @option{-d}.
2315
2316 @item --prefix=@var{prefix}
2317 @cindex Add prefix to absolute paths
2318 Specify @var{prefix} to add to the absolute paths when used with
2319 @option{-S}.
2320
2321 @item --prefix-strip=@var{level}
2322 @cindex Strip absolute paths
2323 Indicate how many initial directory names to strip off the hardwired
2324 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2325
2326 @item --show-raw-insn
2327 When disassembling instructions, print the instruction in hex as well as
2328 in symbolic form. This is the default except when
2329 @option{--prefix-addresses} is used.
2330
2331 @item --no-show-raw-insn
2332 When disassembling instructions, do not print the instruction bytes.
2333 This is the default when @option{--prefix-addresses} is used.
2334
2335 @item --insn-width=@var{width}
2336 @cindex Instruction width
2337 Display @var{width} bytes on a single line when disassembling
2338 instructions.
2339
2340 @item -W[lLiaprmfFsoRt]
2341 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
2342 @itemx --dwarf[=aranges,=macro,=frames,=frames-interp,=str,=loc]
2343 @itemx --dwarf[=Ranges,=pubtypes,=trace_info,=trace_abbrev]
2344 @itemx --dwarf[=trace_aranges,=gdb_index]
2345 @cindex DWARF
2346 @cindex debug symbols
2347 Displays the contents of the debug sections in the file, if any are
2348 present. If one of the optional letters or words follows the switch
2349 then only data found in those specific sections will be dumped.
2350
2351 Note that there is no single letter option to display the content of
2352 trace sections or .gdb_index.
2353
2354 Note: the output from the @option{=info} option can also be affected
2355 by the options @option{--dwarf-depth}, the @option{--dwarf-start} and
2356 the @option{--dwarf-check}.
2357
2358 @item --dwarf-depth=@var{n}
2359 Limit the dump of the @code{.debug_info} section to @var{n} children.
2360 This is only useful with @option{--dwarf=info}. The default is
2361 to print all DIEs; the special value 0 for @var{n} will also have this
2362 effect.
2363
2364 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
2365 levels will not be printed. The range for @var{n} is zero-based.
2366
2367 @item --dwarf-start=@var{n}
2368 Print only DIEs beginning with the DIE numbered @var{n}. This is only
2369 useful with @option{--dwarf=info}.
2370
2371 If specified, this option will suppress printing of any header
2372 information and all DIEs before the DIE numbered @var{n}. Only
2373 siblings and children of the specified DIE will be printed.
2374
2375 This can be used in conjunction with @option{--dwarf-depth}.
2376
2377 @item --dwarf-check
2378 Enable additional checks for consistency of Dwarf information.
2379
2380 @item -G
2381 @itemx --stabs
2382 @cindex stab
2383 @cindex .stab
2384 @cindex debug symbols
2385 @cindex ELF object file format
2386 Display the full contents of any sections requested. Display the
2387 contents of the .stab and .stab.index and .stab.excl sections from an
2388 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2389 @code{.stab} debugging symbol-table entries are carried in an ELF
2390 section. In most other file formats, debugging symbol-table entries are
2391 interleaved with linkage symbols, and are visible in the @option{--syms}
2392 output.
2393
2394 @item --start-address=@var{address}
2395 @cindex start-address
2396 Start displaying data at the specified address. This affects the output
2397 of the @option{-d}, @option{-r} and @option{-s} options.
2398
2399 @item --stop-address=@var{address}
2400 @cindex stop-address
2401 Stop displaying data at the specified address. This affects the output
2402 of the @option{-d}, @option{-r} and @option{-s} options.
2403
2404 @item -t
2405 @itemx --syms
2406 @cindex symbol table entries, printing
2407 Print the symbol table entries of the file.
2408 This is similar to the information provided by the @samp{nm} program,
2409 although the display format is different. The format of the output
2410 depends upon the format of the file being dumped, but there are two main
2411 types. One looks like this:
2412
2413 @smallexample
2414 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2415 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2416 @end smallexample
2417
2418 where the number inside the square brackets is the number of the entry
2419 in the symbol table, the @var{sec} number is the section number, the
2420 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2421 symbol's type, the @var{scl} number is the symbol's storage class and
2422 the @var{nx} value is the number of auxilary entries associated with
2423 the symbol. The last two fields are the symbol's value and its name.
2424
2425 The other common output format, usually seen with ELF based files,
2426 looks like this:
2427
2428 @smallexample
2429 00000000 l d .bss 00000000 .bss
2430 00000000 g .text 00000000 fred
2431 @end smallexample
2432
2433 Here the first number is the symbol's value (sometimes refered to as
2434 its address). The next field is actually a set of characters and
2435 spaces indicating the flag bits that are set on the symbol. These
2436 characters are described below. Next is the section with which the
2437 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2438 not connected with any section), or @emph{*UND*} if the section is
2439 referenced in the file being dumped, but not defined there.
2440
2441 After the section name comes another field, a number, which for common
2442 symbols is the alignment and for other symbol is the size. Finally
2443 the symbol's name is displayed.
2444
2445 The flag characters are divided into 7 groups as follows:
2446 @table @code
2447 @item l
2448 @itemx g
2449 @itemx u
2450 @itemx !
2451 The symbol is a local (l), global (g), unique global (u), neither
2452 global nor local (a space) or both global and local (!). A
2453 symbol can be neither local or global for a variety of reasons, e.g.,
2454 because it is used for debugging, but it is probably an indication of
2455 a bug if it is ever both local and global. Unique global symbols are
2456 a GNU extension to the standard set of ELF symbol bindings. For such
2457 a symbol the dynamic linker will make sure that in the entire process
2458 there is just one symbol with this name and type in use.
2459
2460 @item w
2461 The symbol is weak (w) or strong (a space).
2462
2463 @item C
2464 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2465
2466 @item W
2467 The symbol is a warning (W) or a normal symbol (a space). A warning
2468 symbol's name is a message to be displayed if the symbol following the
2469 warning symbol is ever referenced.
2470
2471 @item I
2472 @item i
2473 The symbol is an indirect reference to another symbol (I), a function
2474 to be evaluated during reloc processing (i) or a normal symbol (a
2475 space).
2476
2477 @item d
2478 @itemx D
2479 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2480 normal symbol (a space).
2481
2482 @item F
2483 @item f
2484 @item O
2485 The symbol is the name of a function (F) or a file (f) or an object
2486 (O) or just a normal symbol (a space).
2487 @end table
2488
2489 @item -T
2490 @itemx --dynamic-syms
2491 @cindex dynamic symbol table entries, printing
2492 Print the dynamic symbol table entries of the file. This is only
2493 meaningful for dynamic objects, such as certain types of shared
2494 libraries. This is similar to the information provided by the @samp{nm}
2495 program when given the @option{-D} (@option{--dynamic}) option.
2496
2497 @item --special-syms
2498 When displaying symbols include those which the target considers to be
2499 special in some way and which would not normally be of interest to the
2500 user.
2501
2502 @item -V
2503 @itemx --version
2504 Print the version number of @command{objdump} and exit.
2505
2506 @item -x
2507 @itemx --all-headers
2508 @cindex all header information, object file
2509 @cindex header information, all
2510 Display all available header information, including the symbol table and
2511 relocation entries. Using @option{-x} is equivalent to specifying all of
2512 @option{-a -f -h -p -r -t}.
2513
2514 @item -w
2515 @itemx --wide
2516 @cindex wide output, printing
2517 Format some lines for output devices that have more than 80 columns.
2518 Also do not truncate symbol names when they are displayed.
2519
2520 @item -z
2521 @itemx --disassemble-zeroes
2522 Normally the disassembly output will skip blocks of zeroes. This
2523 option directs the disassembler to disassemble those blocks, just like
2524 any other data.
2525 @end table
2526
2527 @c man end
2528
2529 @ignore
2530 @c man begin SEEALSO objdump
2531 nm(1), readelf(1), and the Info entries for @file{binutils}.
2532 @c man end
2533 @end ignore
2534
2535 @node ranlib
2536 @chapter ranlib
2537
2538 @kindex ranlib
2539 @cindex archive contents
2540 @cindex symbol index
2541
2542 @c man title ranlib generate index to archive.
2543
2544 @smallexample
2545 @c man begin SYNOPSIS ranlib
2546 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2547 @c man end
2548 @end smallexample
2549
2550 @c man begin DESCRIPTION ranlib
2551
2552 @command{ranlib} generates an index to the contents of an archive and
2553 stores it in the archive. The index lists each symbol defined by a
2554 member of an archive that is a relocatable object file.
2555
2556 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2557
2558 An archive with such an index speeds up linking to the library and
2559 allows routines in the library to call each other without regard to
2560 their placement in the archive.
2561
2562 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2563 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2564 @xref{ar}.
2565
2566 @c man end
2567
2568 @c man begin OPTIONS ranlib
2569
2570 @table @env
2571 @item -h
2572 @itemx -H
2573 @itemx --help
2574 Show usage information for @command{ranlib}.
2575
2576 @item -v
2577 @itemx -V
2578 @itemx --version
2579 Show the version number of @command{ranlib}.
2580
2581 @item -D
2582 @cindex deterministic archives
2583 @kindex --enable-deterministic-archives
2584 Operate in @emph{deterministic} mode. The symbol map archive member's
2585 header will show zero for the UID, GID, and timestamp. When this
2586 option is used, multiple runs will produce identical output files.
2587
2588 If @file{binutils} was configured with
2589 @option{--enable-deterministic-archives}, then this mode is on by
2590 default. It can be disabled with the @samp{-U} option, described
2591 below.
2592
2593 @item -t
2594 Update the timestamp of the symbol map of an archive.
2595
2596 @item -U
2597 @cindex deterministic archives
2598 @kindex --enable-deterministic-archives
2599 Do @emph{not} operate in @emph{deterministic} mode. This is the
2600 inverse of the @samp{-D} option, above: the archive index will get
2601 actual UID, GID, timestamp, and file mode values.
2602
2603 If @file{binutils} was configured @emph{without}
2604 @option{--enable-deterministic-archives}, then this mode is on by
2605 default.
2606
2607 @end table
2608
2609 @c man end
2610
2611 @ignore
2612 @c man begin SEEALSO ranlib
2613 ar(1), nm(1), and the Info entries for @file{binutils}.
2614 @c man end
2615 @end ignore
2616
2617 @node size
2618 @chapter size
2619
2620 @kindex size
2621 @cindex section sizes
2622
2623 @c man title size list section sizes and total size.
2624
2625 @smallexample
2626 @c man begin SYNOPSIS size
2627 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2628 [@option{--help}]
2629 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2630 [@option{--common}]
2631 [@option{-t}|@option{--totals}]
2632 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2633 [@var{objfile}@dots{}]
2634 @c man end
2635 @end smallexample
2636
2637 @c man begin DESCRIPTION size
2638
2639 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2640 size---for each of the object or archive files @var{objfile} in its
2641 argument list. By default, one line of output is generated for each
2642 object file or each module in an archive.
2643
2644 @var{objfile}@dots{} are the object files to be examined.
2645 If none are specified, the file @code{a.out} will be used.
2646
2647 @c man end
2648
2649 @c man begin OPTIONS size
2650
2651 The command line options have the following meanings:
2652
2653 @table @env
2654 @item -A
2655 @itemx -B
2656 @itemx --format=@var{compatibility}
2657 @cindex @command{size} display format
2658 Using one of these options, you can choose whether the output from @sc{gnu}
2659 @command{size} resembles output from System V @command{size} (using @option{-A},
2660 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2661 @option{--format=berkeley}). The default is the one-line format similar to
2662 Berkeley's.
2663 @c Bonus for doc-source readers: you can also say --format=strange (or
2664 @c anything else that starts with 's') for sysv, and --format=boring (or
2665 @c anything else that starts with 'b') for Berkeley.
2666
2667 Here is an example of the Berkeley (default) format of output from
2668 @command{size}:
2669 @smallexample
2670 $ size --format=Berkeley ranlib size
2671 text data bss dec hex filename
2672 294880 81920 11592 388392 5ed28 ranlib
2673 294880 81920 11888 388688 5ee50 size
2674 @end smallexample
2675
2676 @noindent
2677 This is the same data, but displayed closer to System V conventions:
2678
2679 @smallexample
2680 $ size --format=SysV ranlib size
2681 ranlib :
2682 section size addr
2683 .text 294880 8192
2684 .data 81920 303104
2685 .bss 11592 385024
2686 Total 388392
2687
2688
2689 size :
2690 section size addr
2691 .text 294880 8192
2692 .data 81920 303104
2693 .bss 11888 385024
2694 Total 388688
2695 @end smallexample
2696
2697 @item --help
2698 Show a summary of acceptable arguments and options.
2699
2700 @item -d
2701 @itemx -o
2702 @itemx -x
2703 @itemx --radix=@var{number}
2704 @cindex @command{size} number format
2705 @cindex radix for section sizes
2706 Using one of these options, you can control whether the size of each
2707 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2708 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2709 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2710 values (8, 10, 16) are supported. The total size is always given in two
2711 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2712 octal and hexadecimal if you're using @option{-o}.
2713
2714 @item --common
2715 Print total size of common symbols in each file. When using Berkeley
2716 format these are included in the bss size.
2717
2718 @item -t
2719 @itemx --totals
2720 Show totals of all objects listed (Berkeley format listing mode only).
2721
2722 @item --target=@var{bfdname}
2723 @cindex object code format
2724 Specify that the object-code format for @var{objfile} is
2725 @var{bfdname}. This option may not be necessary; @command{size} can
2726 automatically recognize many formats.
2727 @xref{Target Selection}, for more information.
2728
2729 @item -V
2730 @itemx --version
2731 Display the version number of @command{size}.
2732 @end table
2733
2734 @c man end
2735
2736 @ignore
2737 @c man begin SEEALSO size
2738 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2739 @c man end
2740 @end ignore
2741
2742 @node strings
2743 @chapter strings
2744 @kindex strings
2745 @cindex listings strings
2746 @cindex printing strings
2747 @cindex strings, printing
2748
2749 @c man title strings print the strings of printable characters in files.
2750
2751 @smallexample
2752 @c man begin SYNOPSIS strings
2753 strings [@option{-afovV}] [@option{-}@var{min-len}]
2754 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2755 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2756 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2757 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2758 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2759 [@option{-w}] [@option{--include-all-whitespace}]
2760 [@option{--help}] [@option{--version}] @var{file}@dots{}
2761 @c man end
2762 @end smallexample
2763
2764 @c man begin DESCRIPTION strings
2765
2766 For each @var{file} given, @sc{gnu} @command{strings} prints the
2767 printable character sequences that are at least 4 characters long (or
2768 the number given with the options below) and are followed by an
2769 unprintable character.
2770
2771 Depending upon how the strings program was configured it will default
2772 to either displaying all the printable sequences that it can find in
2773 each file, or only those sequences that are in loadable, initialized
2774 data sections. If the file type in unrecognizable, or if strings is
2775 reading from stdin then it will always display all of the printable
2776 sequences that it can find.
2777
2778 For backwards compatibility any file that occurs after a command line
2779 option of just @option{-} will also be scanned in full, regardless of
2780 the presence of any @option{-d} option.
2781
2782 @command{strings} is mainly useful for determining the contents of
2783 non-text files.
2784
2785 @c man end
2786
2787 @c man begin OPTIONS strings
2788
2789 @table @env
2790 @item -a
2791 @itemx --all
2792 @itemx -
2793 Scan the whole file, regardless of what sections it contains or
2794 whether those sections are loaded or initialized. Normally this is
2795 the default behaviour, but strings can be configured so that the
2796 @option{-d} is the default instead.
2797
2798 The @option{-} option is position dependent and forces strings to
2799 perform full scans of any file that is mentioned after the @option{-}
2800 on the command line, even if the @option{-d} option has been
2801 specified.
2802
2803 @item -d
2804 @itemx --data
2805 Only print strings from initialized, loaded data sections in the
2806 file. This may reduce the amount of garbage in the output, but it
2807 also exposes the strings program to any security flaws that may be
2808 present in the BFD library used to scan and load sections. Strings
2809 can be configured so that this option is the default behaviour. In
2810 such cases the @option{-a} option can be used to avoid using the BFD
2811 library and instead just print all of the strings found in the file.
2812
2813 @item -f
2814 @itemx --print-file-name
2815 Print the name of the file before each string.
2816
2817 @item --help
2818 Print a summary of the program usage on the standard output and exit.
2819
2820 @item -@var{min-len}
2821 @itemx -n @var{min-len}
2822 @itemx --bytes=@var{min-len}
2823 Print sequences of characters that are at least @var{min-len} characters
2824 long, instead of the default 4.
2825
2826 @item -o
2827 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2828 act like @samp{-t d} instead. Since we can not be compatible with both
2829 ways, we simply chose one.
2830
2831 @item -t @var{radix}
2832 @itemx --radix=@var{radix}
2833 Print the offset within the file before each string. The single
2834 character argument specifies the radix of the offset---@samp{o} for
2835 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2836
2837 @item -e @var{encoding}
2838 @itemx --encoding=@var{encoding}
2839 Select the character encoding of the strings that are to be found.
2840 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2841 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2842 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2843 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2844 littleendian. Useful for finding wide character strings. (@samp{l}
2845 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
2846
2847 @item -T @var{bfdname}
2848 @itemx --target=@var{bfdname}
2849 @cindex object code format
2850 Specify an object code format other than your system's default format.
2851 @xref{Target Selection}, for more information.
2852
2853 @item -v
2854 @itemx -V
2855 @itemx --version
2856 Print the program version number on the standard output and exit.
2857
2858 @item -w
2859 @itemx --include-all-whitespace
2860 By default tab and space characters are included in the strings that
2861 are displayed, but other whitespace characters, such a newlines and
2862 carriage returns, are not. The @option{-w} option changes this so
2863 that all whitespace characters are considered to be part of a string.
2864 @end table
2865
2866 @c man end
2867
2868 @ignore
2869 @c man begin SEEALSO strings
2870 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2871 and the Info entries for @file{binutils}.
2872 @c man end
2873 @end ignore
2874
2875 @node strip
2876 @chapter strip
2877
2878 @kindex strip
2879 @cindex removing symbols
2880 @cindex discarding symbols
2881 @cindex symbols, discarding
2882
2883 @c man title strip Discard symbols from object files.
2884
2885 @smallexample
2886 @c man begin SYNOPSIS strip
2887 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2888 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2889 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2890 [@option{-s}|@option{--strip-all}]
2891 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2892 [@option{--strip-dwo}]
2893 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2894 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2895 [@option{-w}|@option{--wildcard}]
2896 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2897 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2898 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2899 [@option{-D}|@option{--enable-deterministic-archives}]
2900 [@option{-U}|@option{--disable-deterministic-archives}]
2901 [@option{--keep-file-symbols}]
2902 [@option{--only-keep-debug}]
2903 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2904 [@option{--help}] [@option{--info}]
2905 @var{objfile}@dots{}
2906 @c man end
2907 @end smallexample
2908
2909 @c man begin DESCRIPTION strip
2910
2911 @sc{gnu} @command{strip} discards all symbols from object files
2912 @var{objfile}. The list of object files may include archives.
2913 At least one object file must be given.
2914
2915 @command{strip} modifies the files named in its argument,
2916 rather than writing modified copies under different names.
2917
2918 @c man end
2919
2920 @c man begin OPTIONS strip
2921
2922 @table @env
2923 @item -F @var{bfdname}
2924 @itemx --target=@var{bfdname}
2925 Treat the original @var{objfile} as a file with the object
2926 code format @var{bfdname}, and rewrite it in the same format.
2927 @xref{Target Selection}, for more information.
2928
2929 @item --help
2930 Show a summary of the options to @command{strip} and exit.
2931
2932 @item --info
2933 Display a list showing all architectures and object formats available.
2934
2935 @item -I @var{bfdname}
2936 @itemx --input-target=@var{bfdname}
2937 Treat the original @var{objfile} as a file with the object
2938 code format @var{bfdname}.
2939 @xref{Target Selection}, for more information.
2940
2941 @item -O @var{bfdname}
2942 @itemx --output-target=@var{bfdname}
2943 Replace @var{objfile} with a file in the output format @var{bfdname}.
2944 @xref{Target Selection}, for more information.
2945
2946 @item -R @var{sectionname}
2947 @itemx --remove-section=@var{sectionname}
2948 Remove any section named @var{sectionname} from the output file, in
2949 addition to whatever sections would otherwise be removed. This
2950 option may be given more than once. Note that using this option
2951 inappropriately may make the output file unusable. The wildcard
2952 character @samp{*} may be given at the end of @var{sectionname}. If
2953 so, then any section starting with @var{sectionname} will be removed.
2954
2955 @item -s
2956 @itemx --strip-all
2957 Remove all symbols.
2958
2959 @item -g
2960 @itemx -S
2961 @itemx -d
2962 @itemx --strip-debug
2963 Remove debugging symbols only.
2964
2965 @item --strip-dwo
2966 Remove the contents of all DWARF .dwo sections, leaving the
2967 remaining debugging sections and all symbols intact.
2968 See the description of this option in the @command{objcopy} section
2969 for more information.
2970
2971 @item --strip-unneeded
2972 Remove all symbols that are not needed for relocation processing.
2973
2974 @item -K @var{symbolname}
2975 @itemx --keep-symbol=@var{symbolname}
2976 When stripping symbols, keep symbol @var{symbolname} even if it would
2977 normally be stripped. This option may be given more than once.
2978
2979 @item -N @var{symbolname}
2980 @itemx --strip-symbol=@var{symbolname}
2981 Remove symbol @var{symbolname} from the source file. This option may be
2982 given more than once, and may be combined with strip options other than
2983 @option{-K}.
2984
2985 @item -o @var{file}
2986 Put the stripped output in @var{file}, rather than replacing the
2987 existing file. When this argument is used, only one @var{objfile}
2988 argument may be specified.
2989
2990 @item -p
2991 @itemx --preserve-dates
2992 Preserve the access and modification dates of the file.
2993
2994 @item -D
2995 @itemx --enable-deterministic-archives
2996 @cindex deterministic archives
2997 @kindex --enable-deterministic-archives
2998 Operate in @emph{deterministic} mode. When copying archive members
2999 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3000 and use consistent file modes for all files.
3001
3002 If @file{binutils} was configured with
3003 @option{--enable-deterministic-archives}, then this mode is on by default.
3004 It can be disabled with the @samp{-U} option, below.
3005
3006 @item -U
3007 @itemx --disable-deterministic-archives
3008 @cindex deterministic archives
3009 @kindex --enable-deterministic-archives
3010 Do @emph{not} operate in @emph{deterministic} mode. This is the
3011 inverse of the @option{-D} option, above: when copying archive members
3012 and writing the archive index, use their actual UID, GID, timestamp,
3013 and file mode values.
3014
3015 This is the default unless @file{binutils} was configured with
3016 @option{--enable-deterministic-archives}.
3017
3018 @item -w
3019 @itemx --wildcard
3020 Permit regular expressions in @var{symbolname}s used in other command
3021 line options. The question mark (?), asterisk (*), backslash (\) and
3022 square brackets ([]) operators can be used anywhere in the symbol
3023 name. If the first character of the symbol name is the exclamation
3024 point (!) then the sense of the switch is reversed for that symbol.
3025 For example:
3026
3027 @smallexample
3028 -w -K !foo -K fo*
3029 @end smallexample
3030
3031 would cause strip to only keep symbols that start with the letters
3032 ``fo'', but to discard the symbol ``foo''.
3033
3034 @item -x
3035 @itemx --discard-all
3036 Remove non-global symbols.
3037
3038 @item -X
3039 @itemx --discard-locals
3040 Remove compiler-generated local symbols.
3041 (These usually start with @samp{L} or @samp{.}.)
3042
3043 @item --keep-file-symbols
3044 When stripping a file, perhaps with @option{--strip-debug} or
3045 @option{--strip-unneeded}, retain any symbols specifying source file names,
3046 which would otherwise get stripped.
3047
3048 @item --only-keep-debug
3049 Strip a file, removing contents of any sections that would not be
3050 stripped by @option{--strip-debug} and leaving the debugging sections
3051 intact. In ELF files, this preserves all note sections in the output.
3052
3053 The intention is that this option will be used in conjunction with
3054 @option{--add-gnu-debuglink} to create a two part executable. One a
3055 stripped binary which will occupy less space in RAM and in a
3056 distribution and the second a debugging information file which is only
3057 needed if debugging abilities are required. The suggested procedure
3058 to create these files is as follows:
3059
3060 @enumerate
3061 @item Link the executable as normal. Assuming that is is called
3062 @code{foo} then...
3063 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3064 create a file containing the debugging info.
3065 @item Run @code{objcopy --strip-debug foo} to create a
3066 stripped executable.
3067 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3068 to add a link to the debugging info into the stripped executable.
3069 @end enumerate
3070
3071 Note---the choice of @code{.dbg} as an extension for the debug info
3072 file is arbitrary. Also the @code{--only-keep-debug} step is
3073 optional. You could instead do this:
3074
3075 @enumerate
3076 @item Link the executable as normal.
3077 @item Copy @code{foo} to @code{foo.full}
3078 @item Run @code{strip --strip-debug foo}
3079 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3080 @end enumerate
3081
3082 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3083 full executable. It does not have to be a file created by the
3084 @option{--only-keep-debug} switch.
3085
3086 Note---this switch is only intended for use on fully linked files. It
3087 does not make sense to use it on object files where the debugging
3088 information may be incomplete. Besides the gnu_debuglink feature
3089 currently only supports the presence of one filename containing
3090 debugging information, not multiple filenames on a one-per-object-file
3091 basis.
3092
3093 @item -V
3094 @itemx --version
3095 Show the version number for @command{strip}.
3096
3097 @item -v
3098 @itemx --verbose
3099 Verbose output: list all object files modified. In the case of
3100 archives, @samp{strip -v} lists all members of the archive.
3101 @end table
3102
3103 @c man end
3104
3105 @ignore
3106 @c man begin SEEALSO strip
3107 the Info entries for @file{binutils}.
3108 @c man end
3109 @end ignore
3110
3111 @node c++filt, addr2line, strip, Top
3112 @chapter c++filt
3113
3114 @kindex c++filt
3115 @cindex demangling C++ symbols
3116
3117 @c man title cxxfilt Demangle C++ and Java symbols.
3118
3119 @smallexample
3120 @c man begin SYNOPSIS cxxfilt
3121 c++filt [@option{-_}|@option{--strip-underscore}]
3122 [@option{-n}|@option{--no-strip-underscore}]
3123 [@option{-p}|@option{--no-params}]
3124 [@option{-t}|@option{--types}]
3125 [@option{-i}|@option{--no-verbose}]
3126 [@option{-s} @var{format}|@option{--format=}@var{format}]
3127 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3128 @c man end
3129 @end smallexample
3130
3131 @c man begin DESCRIPTION cxxfilt
3132
3133 @kindex cxxfilt
3134 The C++ and Java languages provide function overloading, which means
3135 that you can write many functions with the same name, providing that
3136 each function takes parameters of different types. In order to be
3137 able to distinguish these similarly named functions C++ and Java
3138 encode them into a low-level assembler name which uniquely identifies
3139 each different version. This process is known as @dfn{mangling}. The
3140 @command{c++filt}
3141 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3142 MS-DOS this program is named @command{CXXFILT}.}
3143 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3144 names into user-level names so that they can be read.
3145
3146 Every alphanumeric word (consisting of letters, digits, underscores,
3147 dollars, or periods) seen in the input is a potential mangled name.
3148 If the name decodes into a C++ name, the C++ name replaces the
3149 low-level name in the output, otherwise the original word is output.
3150 In this way you can pass an entire assembler source file, containing
3151 mangled names, through @command{c++filt} and see the same source file
3152 containing demangled names.
3153
3154 You can also use @command{c++filt} to decipher individual symbols by
3155 passing them on the command line:
3156
3157 @example
3158 c++filt @var{symbol}
3159 @end example
3160
3161 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3162 names from the standard input instead. All the results are printed on
3163 the standard output. The difference between reading names from the
3164 command line versus reading names from the standard input is that
3165 command line arguments are expected to be just mangled names and no
3166 checking is performed to separate them from surrounding text. Thus
3167 for example:
3168
3169 @smallexample
3170 c++filt -n _Z1fv
3171 @end smallexample
3172
3173 will work and demangle the name to ``f()'' whereas:
3174
3175 @smallexample
3176 c++filt -n _Z1fv,
3177 @end smallexample
3178
3179 will not work. (Note the extra comma at the end of the mangled
3180 name which makes it invalid). This command however will work:
3181
3182 @smallexample
3183 echo _Z1fv, | c++filt -n
3184 @end smallexample
3185
3186 and will display ``f(),'', i.e., the demangled name followed by a
3187 trailing comma. This behaviour is because when the names are read
3188 from the standard input it is expected that they might be part of an
3189 assembler source file where there might be extra, extraneous
3190 characters trailing after a mangled name. For example:
3191
3192 @smallexample
3193 .type _Z1fv, @@function
3194 @end smallexample
3195
3196 @c man end
3197
3198 @c man begin OPTIONS cxxfilt
3199
3200 @table @env
3201 @item -_
3202 @itemx --strip-underscore
3203 On some systems, both the C and C++ compilers put an underscore in front
3204 of every name. For example, the C name @code{foo} gets the low-level
3205 name @code{_foo}. This option removes the initial underscore. Whether
3206 @command{c++filt} removes the underscore by default is target dependent.
3207
3208 @item -n
3209 @itemx --no-strip-underscore
3210 Do not remove the initial underscore.
3211
3212 @item -p
3213 @itemx --no-params
3214 When demangling the name of a function, do not display the types of
3215 the function's parameters.
3216
3217 @item -t
3218 @itemx --types
3219 Attempt to demangle types as well as function names. This is disabled
3220 by default since mangled types are normally only used internally in
3221 the compiler, and they can be confused with non-mangled names. For example,
3222 a function called ``a'' treated as a mangled type name would be
3223 demangled to ``signed char''.
3224
3225 @item -i
3226 @itemx --no-verbose
3227 Do not include implementation details (if any) in the demangled
3228 output.
3229
3230 @item -s @var{format}
3231 @itemx --format=@var{format}
3232 @command{c++filt} can decode various methods of mangling, used by
3233 different compilers. The argument to this option selects which
3234 method it uses:
3235
3236 @table @code
3237 @item auto
3238 Automatic selection based on executable (the default method)
3239 @item gnu
3240 the one used by the @sc{gnu} C++ compiler (g++)
3241 @item lucid
3242 the one used by the Lucid compiler (lcc)
3243 @item arm
3244 the one specified by the C++ Annotated Reference Manual
3245 @item hp
3246 the one used by the HP compiler (aCC)
3247 @item edg
3248 the one used by the EDG compiler
3249 @item gnu-v3
3250 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3251 @item java
3252 the one used by the @sc{gnu} Java compiler (gcj)
3253 @item gnat
3254 the one used by the @sc{gnu} Ada compiler (GNAT).
3255 @end table
3256
3257 @item --help
3258 Print a summary of the options to @command{c++filt} and exit.
3259
3260 @item --version
3261 Print the version number of @command{c++filt} and exit.
3262 @end table
3263
3264 @c man end
3265
3266 @ignore
3267 @c man begin SEEALSO cxxfilt
3268 the Info entries for @file{binutils}.
3269 @c man end
3270 @end ignore
3271
3272 @quotation
3273 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3274 user interface are subject to change in future releases. In particular,
3275 a command-line option may be required in the future to decode a name
3276 passed as an argument on the command line; in other words,
3277
3278 @example
3279 c++filt @var{symbol}
3280 @end example
3281
3282 @noindent
3283 may in a future release become
3284
3285 @example
3286 c++filt @var{option} @var{symbol}
3287 @end example
3288 @end quotation
3289
3290 @node addr2line
3291 @chapter addr2line
3292
3293 @kindex addr2line
3294 @cindex address to file name and line number
3295
3296 @c man title addr2line convert addresses into file names and line numbers.
3297
3298 @smallexample
3299 @c man begin SYNOPSIS addr2line
3300 addr2line [@option{-a}|@option{--addresses}]
3301 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3302 [@option{-C}|@option{--demangle}[=@var{style}]]
3303 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3304 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3305 [@option{-i}|@option{--inlines}]
3306 [@option{-p}|@option{--pretty-print}]
3307 [@option{-j}|@option{--section=}@var{name}]
3308 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3309 [addr addr @dots{}]
3310 @c man end
3311 @end smallexample
3312
3313 @c man begin DESCRIPTION addr2line
3314
3315 @command{addr2line} translates addresses into file names and line numbers.
3316 Given an address in an executable or an offset in a section of a relocatable
3317 object, it uses the debugging information to figure out which file name and
3318 line number are associated with it.
3319
3320 The executable or relocatable object to use is specified with the @option{-e}
3321 option. The default is the file @file{a.out}. The section in the relocatable
3322 object to use is specified with the @option{-j} option.
3323
3324 @command{addr2line} has two modes of operation.
3325
3326 In the first, hexadecimal addresses are specified on the command line,
3327 and @command{addr2line} displays the file name and line number for each
3328 address.
3329
3330 In the second, @command{addr2line} reads hexadecimal addresses from
3331 standard input, and prints the file name and line number for each
3332 address on standard output. In this mode, @command{addr2line} may be used
3333 in a pipe to convert dynamically chosen addresses.
3334
3335 The format of the output is @samp{FILENAME:LINENO}. By default
3336 each input address generates one line of output.
3337
3338 Two options can generate additional lines before each
3339 @samp{FILENAME:LINENO} line (in that order).
3340
3341 If the @option{-a} option is used then a line with the input address
3342 is displayed.
3343
3344 If the @option{-f} option is used, then a line with the
3345 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3346 containing the address.
3347
3348 One option can generate additional lines after the
3349 @samp{FILENAME:LINENO} line.
3350
3351 If the @option{-i} option is used and the code at the given address is
3352 present there because of inlining by the compiler then additional
3353 lines are displayed afterwards. One or two extra lines (if the
3354 @option{-f} option is used) are displayed for each inlined function.
3355
3356 Alternatively if the @option{-p} option is used then each input
3357 address generates a single, long, output line containing the address,
3358 the function name, the file name and the line number. If the
3359 @option{-i} option has also been used then any inlined functions will
3360 be displayed in the same manner, but on separate lines, and prefixed
3361 by the text @samp{(inlined by)}.
3362
3363 If the file name or function name can not be determined,
3364 @command{addr2line} will print two question marks in their place. If the
3365 line number can not be determined, @command{addr2line} will print 0.
3366
3367 @c man end
3368
3369 @c man begin OPTIONS addr2line
3370
3371 The long and short forms of options, shown here as alternatives, are
3372 equivalent.
3373
3374 @table @env
3375 @item -a
3376 @itemx --addresses
3377 Display the address before the function name, file and line number
3378 information. The address is printed with a @samp{0x} prefix to easily
3379 identify it.
3380
3381 @item -b @var{bfdname}
3382 @itemx --target=@var{bfdname}
3383 @cindex object code format
3384 Specify that the object-code format for the object files is
3385 @var{bfdname}.
3386
3387 @item -C
3388 @itemx --demangle[=@var{style}]
3389 @cindex demangling in objdump
3390 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3391 Besides removing any initial underscore prepended by the system, this
3392 makes C++ function names readable. Different compilers have different
3393 mangling styles. The optional demangling style argument can be used to
3394 choose an appropriate demangling style for your compiler. @xref{c++filt},
3395 for more information on demangling.
3396
3397 @item -e @var{filename}
3398 @itemx --exe=@var{filename}
3399 Specify the name of the executable for which addresses should be
3400 translated. The default file is @file{a.out}.
3401
3402 @item -f
3403 @itemx --functions
3404 Display function names as well as file and line number information.
3405
3406 @item -s
3407 @itemx --basenames
3408 Display only the base of each file name.
3409
3410 @item -i
3411 @itemx --inlines
3412 If the address belongs to a function that was inlined, the source
3413 information for all enclosing scopes back to the first non-inlined
3414 function will also be printed. For example, if @code{main} inlines
3415 @code{callee1} which inlines @code{callee2}, and address is from
3416 @code{callee2}, the source information for @code{callee1} and @code{main}
3417 will also be printed.
3418
3419 @item -j
3420 @itemx --section
3421 Read offsets relative to the specified section instead of absolute addresses.
3422
3423 @item -p
3424 @itemx --pretty-print
3425 Make the output more human friendly: each location are printed on one line.
3426 If option @option{-i} is specified, lines for all enclosing scopes are
3427 prefixed with @samp{(inlined by)}.
3428 @end table
3429
3430 @c man end
3431
3432 @ignore
3433 @c man begin SEEALSO addr2line
3434 Info entries for @file{binutils}.
3435 @c man end
3436 @end ignore
3437
3438 @node nlmconv
3439 @chapter nlmconv
3440
3441 @command{nlmconv} converts a relocatable object file into a NetWare
3442 Loadable Module.
3443
3444 @ignore
3445 @command{nlmconv} currently works with @samp{i386} object
3446 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
3447 object files in @sc{elf}, or @code{a.out} format@footnote{
3448 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
3449 format in the Binary File Descriptor library. It has only been tested
3450 with the above formats.}.
3451 @end ignore
3452
3453 @quotation
3454 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
3455 utilities, since it is only useful for NLM targets.
3456 @end quotation
3457
3458 @c man title nlmconv converts object code into an NLM.
3459
3460 @smallexample
3461 @c man begin SYNOPSIS nlmconv
3462 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
3463 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
3464 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
3465 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
3466 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3467 @var{infile} @var{outfile}
3468 @c man end
3469 @end smallexample
3470
3471 @c man begin DESCRIPTION nlmconv
3472
3473 @command{nlmconv} converts the relocatable @samp{i386} object file
3474 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
3475 reading @var{headerfile} for NLM header information. For instructions
3476 on writing the NLM command file language used in header files, see the
3477 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
3478 Development and Tools Overview}, which is part of the NLM Software
3479 Developer's Kit (``NLM SDK''), available from Novell, Inc.
3480 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
3481 @var{infile};
3482 @ifclear man
3483 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
3484 @end ifclear
3485
3486 @command{nlmconv} can perform a link step. In other words, you can list
3487 more than one object file for input if you list them in the definitions
3488 file (rather than simply specifying one input file on the command line).
3489 In this case, @command{nlmconv} calls the linker for you.
3490
3491 @c man end
3492
3493 @c man begin OPTIONS nlmconv
3494
3495 @table @env
3496 @item -I @var{bfdname}
3497 @itemx --input-target=@var{bfdname}
3498 Object format of the input file. @command{nlmconv} can usually determine
3499 the format of a given file (so no default is necessary).
3500 @xref{Target Selection}, for more information.
3501
3502 @item -O @var{bfdname}
3503 @itemx --output-target=@var{bfdname}
3504 Object format of the output file. @command{nlmconv} infers the output
3505 format based on the input format, e.g. for a @samp{i386} input file the
3506 output format is @samp{nlm32-i386}.
3507 @xref{Target Selection}, for more information.
3508
3509 @item -T @var{headerfile}
3510 @itemx --header-file=@var{headerfile}
3511 Reads @var{headerfile} for NLM header information. For instructions on
3512 writing the NLM command file language used in header files, see@ see the
3513 @samp{linkers} section, of the @cite{NLM Development and Tools
3514 Overview}, which is part of the NLM Software Developer's Kit, available
3515 from Novell, Inc.
3516
3517 @item -d
3518 @itemx --debug
3519 Displays (on standard error) the linker command line used by @command{nlmconv}.
3520
3521 @item -l @var{linker}
3522 @itemx --linker=@var{linker}
3523 Use @var{linker} for any linking. @var{linker} can be an absolute or a
3524 relative pathname.
3525
3526 @item -h
3527 @itemx --help
3528 Prints a usage summary.
3529
3530 @item -V
3531 @itemx --version
3532 Prints the version number for @command{nlmconv}.
3533 @end table
3534
3535 @c man end
3536
3537 @ignore
3538 @c man begin SEEALSO nlmconv
3539 the Info entries for @file{binutils}.
3540 @c man end
3541 @end ignore
3542
3543 @node windmc
3544 @chapter windmc
3545
3546 @command{windmc} may be used to generator Windows message resources.
3547
3548 @quotation
3549 @emph{Warning:} @command{windmc} is not always built as part of the binary
3550 utilities, since it is only useful for Windows targets.
3551 @end quotation
3552
3553 @c man title windmc generates Windows message resources.
3554
3555 @smallexample
3556 @c man begin SYNOPSIS windmc
3557 windmc [options] input-file
3558 @c man end
3559 @end smallexample
3560
3561 @c man begin DESCRIPTION windmc
3562
3563 @command{windmc} reads message definitions from an input file (.mc) and
3564 translate them into a set of output files. The output files may be of
3565 four kinds:
3566
3567 @table @code
3568 @item h
3569 A C header file containing the message definitions.
3570
3571 @item rc
3572 A resource file compilable by the @command{windres} tool.
3573
3574 @item bin
3575 One or more binary files containing the resource data for a specific
3576 message language.
3577
3578 @item dbg
3579 A C include file that maps message id's to their symbolic name.
3580 @end table
3581
3582 The exact description of these different formats is available in
3583 documentation from Microsoft.
3584
3585 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3586 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3587 Windows Message Compiler.
3588
3589 @c man end
3590
3591 @c man begin OPTIONS windmc
3592
3593 @table @env
3594 @item -a
3595 @itemx --ascii_in
3596 Specifies that the input file specified is ASCII. This is the default
3597 behaviour.
3598
3599 @item -A
3600 @itemx --ascii_out
3601 Specifies that messages in the output @code{bin} files should be in ASCII
3602 format.
3603
3604 @item -b
3605 @itemx --binprefix
3606 Specifies that @code{bin} filenames should have to be prefixed by the
3607 basename of the source file.
3608
3609 @item -c
3610 @itemx --customflag
3611 Sets the customer bit in all message id's.
3612
3613 @item -C @var{codepage}
3614 @itemx --codepage_in @var{codepage}
3615 Sets the default codepage to be used to convert input file to UTF16. The
3616 default is ocdepage 1252.
3617
3618 @item -d
3619 @itemx --decimal_values
3620 Outputs the constants in the header file in decimal. Default is using
3621 hexadecimal output.
3622
3623 @item -e @var{ext}
3624 @itemx --extension @var{ext}
3625 The extension for the header file. The default is .h extension.
3626
3627 @item -F @var{target}
3628 @itemx --target @var{target}
3629 Specify the BFD format to use for a bin file as output. This
3630 is a BFD target name; you can use the @option{--help} option to see a list
3631 of supported targets. Normally @command{windmc} will use the default
3632 format, which is the first one listed by the @option{--help} option.
3633 @ifclear man
3634 @ref{Target Selection}.
3635 @end ifclear
3636
3637 @item -h @var{path}
3638 @itemx --headerdir @var{path}
3639 The target directory of the generated header file. The default is the
3640 current directory.
3641
3642 @item -H
3643 @itemx --help
3644 Displays a list of command line options and then exits.
3645
3646 @item -m @var{characters}
3647 @itemx --maxlength @var{characters}
3648 Instructs @command{windmc} to generate a warning if the length
3649 of any message exceeds the number specified.
3650
3651 @item -n
3652 @itemx --nullterminate
3653 Terminate message text in @code{bin} files by zero. By default they are
3654 terminated by CR/LF.
3655
3656 @item -o
3657 @itemx --hresult_use
3658 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3659 file, using HRESULT definitions. Status codes are used if the flag is not
3660 specified.
3661
3662 @item -O @var{codepage}
3663 @itemx --codepage_out @var{codepage}
3664 Sets the default codepage to be used to output text files. The default
3665 is ocdepage 1252.
3666
3667 @item -r @var{path}
3668 @itemx --rcdir @var{path}
3669 The target directory for the generated @code{rc} script and the generated
3670 @code{bin} files that the resource compiler script includes. The default
3671 is the current directory.
3672
3673 @item -u
3674 @itemx --unicode_in
3675 Specifies that the input file is UTF16.
3676
3677 @item -U
3678 @itemx --unicode_out
3679 Specifies that messages in the output @code{bin} file should be in UTF16
3680 format. This is the default behaviour.
3681
3682 @item -v
3683 @item --verbose
3684 Enable verbose mode.
3685
3686 @item -V
3687 @item --version
3688 Prints the version number for @command{windmc}.
3689
3690 @item -x @var{path}
3691 @itemx --xdgb @var{path}
3692 The path of the @code{dbg} C include file that maps message id's to the
3693 symbolic name. No such file is generated without specifying the switch.
3694 @end table
3695
3696 @c man end
3697
3698 @ignore
3699 @c man begin SEEALSO windmc
3700 the Info entries for @file{binutils}.
3701 @c man end
3702 @end ignore
3703
3704 @node windres
3705 @chapter windres
3706
3707 @command{windres} may be used to manipulate Windows resources.
3708
3709 @quotation
3710 @emph{Warning:} @command{windres} is not always built as part of the binary
3711 utilities, since it is only useful for Windows targets.
3712 @end quotation
3713
3714 @c man title windres manipulate Windows resources.
3715
3716 @smallexample
3717 @c man begin SYNOPSIS windres
3718 windres [options] [input-file] [output-file]
3719 @c man end
3720 @end smallexample
3721
3722 @c man begin DESCRIPTION windres
3723
3724 @command{windres} reads resources from an input file and copies them into
3725 an output file. Either file may be in one of three formats:
3726
3727 @table @code
3728 @item rc
3729 A text format read by the Resource Compiler.
3730
3731 @item res
3732 A binary format generated by the Resource Compiler.
3733
3734 @item coff
3735 A COFF object or executable.
3736 @end table
3737
3738 The exact description of these different formats is available in
3739 documentation from Microsoft.
3740
3741 When @command{windres} converts from the @code{rc} format to the @code{res}
3742 format, it is acting like the Windows Resource Compiler. When
3743 @command{windres} converts from the @code{res} format to the @code{coff}
3744 format, it is acting like the Windows @code{CVTRES} program.
3745
3746 When @command{windres} generates an @code{rc} file, the output is similar
3747 but not identical to the format expected for the input. When an input
3748 @code{rc} file refers to an external filename, an output @code{rc} file
3749 will instead include the file contents.
3750
3751 If the input or output format is not specified, @command{windres} will
3752 guess based on the file name, or, for the input file, the file contents.
3753 A file with an extension of @file{.rc} will be treated as an @code{rc}
3754 file, a file with an extension of @file{.res} will be treated as a
3755 @code{res} file, and a file with an extension of @file{.o} or
3756 @file{.exe} will be treated as a @code{coff} file.
3757
3758 If no output file is specified, @command{windres} will print the resources
3759 in @code{rc} format to standard output.
3760
3761 The normal use is for you to write an @code{rc} file, use @command{windres}
3762 to convert it to a COFF object file, and then link the COFF file into
3763 your application. This will make the resources described in the
3764 @code{rc} file available to Windows.
3765
3766 @c man end
3767
3768 @c man begin OPTIONS windres
3769
3770 @table @env
3771 @item -i @var{filename}
3772 @itemx --input @var{filename}
3773 The name of the input file. If this option is not used, then
3774 @command{windres} will use the first non-option argument as the input file
3775 name. If there are no non-option arguments, then @command{windres} will
3776 read from standard input. @command{windres} can not read a COFF file from
3777 standard input.
3778
3779 @item -o @var{filename}
3780 @itemx --output @var{filename}
3781 The name of the output file. If this option is not used, then
3782 @command{windres} will use the first non-option argument, after any used
3783 for the input file name, as the output file name. If there is no
3784 non-option argument, then @command{windres} will write to standard output.
3785 @command{windres} can not write a COFF file to standard output. Note,
3786 for compatibility with @command{rc} the option @option{-fo} is also
3787 accepted, but its use is not recommended.
3788
3789 @item -J @var{format}
3790 @itemx --input-format @var{format}
3791 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3792 @samp{coff}. If no input format is specified, @command{windres} will
3793 guess, as described above.
3794
3795 @item -O @var{format}
3796 @itemx --output-format @var{format}
3797 The output format to generate. @var{format} may be @samp{res},
3798 @samp{rc}, or @samp{coff}. If no output format is specified,
3799 @command{windres} will guess, as described above.
3800
3801 @item -F @var{target}
3802 @itemx --target @var{target}
3803 Specify the BFD format to use for a COFF file as input or output. This
3804 is a BFD target name; you can use the @option{--help} option to see a list
3805 of supported targets. Normally @command{windres} will use the default
3806 format, which is the first one listed by the @option{--help} option.
3807 @ifclear man
3808 @ref{Target Selection}.
3809 @end ifclear
3810
3811 @item --preprocessor @var{program}
3812 When @command{windres} reads an @code{rc} file, it runs it through the C
3813 preprocessor first. This option may be used to specify the preprocessor
3814 to use, including any leading arguments. The default preprocessor
3815 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3816
3817 @item --preprocessor-arg @var{option}
3818 When @command{windres} reads an @code{rc} file, it runs it through
3819 the C preprocessor first. This option may be used to specify additional
3820 text to be passed to preprocessor on its command line.
3821 This option can be used multiple times to add multiple options to the
3822 preprocessor command line.
3823
3824 @item -I @var{directory}
3825 @itemx --include-dir @var{directory}
3826 Specify an include directory to use when reading an @code{rc} file.
3827 @command{windres} will pass this to the preprocessor as an @option{-I}
3828 option. @command{windres} will also search this directory when looking for
3829 files named in the @code{rc} file. If the argument passed to this command
3830 matches any of the supported @var{formats} (as described in the @option{-J}
3831 option), it will issue a deprecation warning, and behave just like the
3832 @option{-J} option. New programs should not use this behaviour. If a
3833 directory happens to match a @var{format}, simple prefix it with @samp{./}
3834 to disable the backward compatibility.
3835
3836 @item -D @var{target}
3837 @itemx --define @var{sym}[=@var{val}]
3838 Specify a @option{-D} option to pass to the preprocessor when reading an
3839 @code{rc} file.
3840
3841 @item -U @var{target}
3842 @itemx --undefine @var{sym}
3843 Specify a @option{-U} option to pass to the preprocessor when reading an
3844 @code{rc} file.
3845
3846 @item -r
3847 Ignored for compatibility with rc.
3848
3849 @item -v
3850 Enable verbose mode. This tells you what the preprocessor is if you
3851 didn't specify one.
3852
3853 @item -c @var{val}
3854 @item --codepage @var{val}
3855 Specify the default codepage to use when reading an @code{rc} file.
3856 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
3857 codepage code. The valid range is from zero up to 0xffff, but the
3858 validity of the codepage is host and configuration dependent.
3859
3860 @item -l @var{val}
3861 @item --language @var{val}
3862 Specify the default language to use when reading an @code{rc} file.
3863 @var{val} should be a hexadecimal language code. The low eight bits are
3864 the language, and the high eight bits are the sublanguage.
3865
3866 @item --use-temp-file
3867 Use a temporary file to instead of using popen to read the output of
3868 the preprocessor. Use this option if the popen implementation is buggy
3869 on the host (eg., certain non-English language versions of Windows 95 and
3870 Windows 98 are known to have buggy popen where the output will instead
3871 go the console).
3872
3873 @item --no-use-temp-file
3874 Use popen, not a temporary file, to read the output of the preprocessor.
3875 This is the default behaviour.
3876
3877 @item -h
3878 @item --help
3879 Prints a usage summary.
3880
3881 @item -V
3882 @item --version
3883 Prints the version number for @command{windres}.
3884
3885 @item --yydebug
3886 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3887 this will turn on parser debugging.
3888 @end table
3889
3890 @c man end
3891
3892 @ignore
3893 @c man begin SEEALSO windres
3894 the Info entries for @file{binutils}.
3895 @c man end
3896 @end ignore
3897
3898 @node dlltool
3899 @chapter dlltool
3900 @cindex DLL
3901 @kindex dlltool
3902
3903 @command{dlltool} is used to create the files needed to create dynamic
3904 link libraries (DLLs) on systems which understand PE format image
3905 files such as Windows. A DLL contains an export table which contains
3906 information that the runtime loader needs to resolve references from a
3907 referencing program.
3908
3909 The export table is generated by this program by reading in a
3910 @file{.def} file or scanning the @file{.a} and @file{.o} files which
3911 will be in the DLL. A @file{.o} file can contain information in
3912 special @samp{.drectve} sections with export information.
3913
3914 @quotation
3915 @emph{Note:} @command{dlltool} is not always built as part of the
3916 binary utilities, since it is only useful for those targets which
3917 support DLLs.
3918 @end quotation
3919
3920 @c man title dlltool Create files needed to build and use DLLs.
3921
3922 @smallexample
3923 @c man begin SYNOPSIS dlltool
3924 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3925 [@option{-b}|@option{--base-file} @var{base-file-name}]
3926 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3927 [@option{-z}|@option{--output-def} @var{def-file-name}]
3928 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3929 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
3930 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3931 [@option{--exclude-symbols} @var{list}]
3932 [@option{--no-default-excludes}]
3933 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3934 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3935 [@option{-a}|@option{--add-indirect}]
3936 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3937 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3938 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3939 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
3940 [@option{--use-nul-prefixed-import-tables}]
3941 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
3942 [@option{-i}|@option{--interwork}]
3943 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3944 [@option{-v}|@option{--verbose}]
3945 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3946 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
3947 [object-file @dots{}]
3948 @c man end
3949 @end smallexample
3950
3951 @c man begin DESCRIPTION dlltool
3952
3953 @command{dlltool} reads its inputs, which can come from the @option{-d} and
3954 @option{-b} options as well as object files specified on the command
3955 line. It then processes these inputs and if the @option{-e} option has
3956 been specified it creates a exports file. If the @option{-l} option
3957 has been specified it creates a library file and if the @option{-z} option
3958 has been specified it creates a def file. Any or all of the @option{-e},
3959 @option{-l} and @option{-z} options can be present in one invocation of
3960 dlltool.
3961
3962 When creating a DLL, along with the source for the DLL, it is necessary
3963 to have three other files. @command{dlltool} can help with the creation of
3964 these files.
3965
3966 The first file is a @file{.def} file which specifies which functions are
3967 exported from the DLL, which functions the DLL imports, and so on. This
3968 is a text file and can be created by hand, or @command{dlltool} can be used
3969 to create it using the @option{-z} option. In this case @command{dlltool}
3970 will scan the object files specified on its command line looking for
3971 those functions which have been specially marked as being exported and
3972 put entries for them in the @file{.def} file it creates.
3973
3974 In order to mark a function as being exported from a DLL, it needs to
3975 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
3976 section of the object file. This can be done in C by using the
3977 asm() operator:
3978
3979 @smallexample
3980 asm (".section .drectve");
3981 asm (".ascii \"-export:my_func\"");
3982
3983 int my_func (void) @{ @dots{} @}
3984 @end smallexample
3985
3986 The second file needed for DLL creation is an exports file. This file
3987 is linked with the object files that make up the body of the DLL and it
3988 handles the interface between the DLL and the outside world. This is a
3989 binary file and it can be created by giving the @option{-e} option to
3990 @command{dlltool} when it is creating or reading in a @file{.def} file.
3991
3992 The third file needed for DLL creation is the library file that programs
3993 will link with in order to access the functions in the DLL (an `import
3994 library'). This file can be created by giving the @option{-l} option to
3995 dlltool when it is creating or reading in a @file{.def} file.
3996
3997 If the @option{-y} option is specified, dlltool generates a delay-import
3998 library that can be used instead of the normal import library to allow
3999 a program to link to the dll only as soon as an imported function is
4000 called for the first time. The resulting executable will need to be
4001 linked to the static delayimp library containing __delayLoadHelper2(),
4002 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4003
4004 @command{dlltool} builds the library file by hand, but it builds the
4005 exports file by creating temporary files containing assembler statements
4006 and then assembling these. The @option{-S} command line option can be
4007 used to specify the path to the assembler that dlltool will use,
4008 and the @option{-f} option can be used to pass specific flags to that
4009 assembler. The @option{-n} can be used to prevent dlltool from deleting
4010 these temporary assembler files when it is done, and if @option{-n} is
4011 specified twice then this will prevent dlltool from deleting the
4012 temporary object files it used to build the library.
4013
4014 Here is an example of creating a DLL from a source file @samp{dll.c} and
4015 also creating a program (from an object file called @samp{program.o})
4016 that uses that DLL:
4017
4018 @smallexample
4019 gcc -c dll.c
4020 dlltool -e exports.o -l dll.lib dll.o
4021 gcc dll.o exports.o -o dll.dll
4022 gcc program.o dll.lib -o program
4023 @end smallexample
4024
4025
4026 @command{dlltool} may also be used to query an existing import library
4027 to determine the name of the DLL to which it is associated. See the
4028 description of the @option{-I} or @option{--identify} option.
4029
4030 @c man end
4031
4032 @c man begin OPTIONS dlltool
4033
4034 The command line options have the following meanings:
4035
4036 @table @env
4037
4038 @item -d @var{filename}
4039 @itemx --input-def @var{filename}
4040 @cindex input .def file
4041 Specifies the name of a @file{.def} file to be read in and processed.
4042
4043 @item -b @var{filename}
4044 @itemx --base-file @var{filename}
4045 @cindex base files
4046 Specifies the name of a base file to be read in and processed. The
4047 contents of this file will be added to the relocation section in the
4048 exports file generated by dlltool.
4049
4050 @item -e @var{filename}
4051 @itemx --output-exp @var{filename}
4052 Specifies the name of the export file to be created by dlltool.
4053
4054 @item -z @var{filename}
4055 @itemx --output-def @var{filename}
4056 Specifies the name of the @file{.def} file to be created by dlltool.
4057
4058 @item -l @var{filename}
4059 @itemx --output-lib @var{filename}
4060 Specifies the name of the library file to be created by dlltool.
4061
4062 @item -y @var{filename}
4063 @itemx --output-delaylib @var{filename}
4064 Specifies the name of the delay-import library file to be created by dlltool.
4065
4066 @item --export-all-symbols
4067 Treat all global and weak defined symbols found in the input object
4068 files as symbols to be exported. There is a small list of symbols which
4069 are not exported by default; see the @option{--no-default-excludes}
4070 option. You may add to the list of symbols to not export by using the
4071 @option{--exclude-symbols} option.
4072
4073 @item --no-export-all-symbols
4074 Only export symbols explicitly listed in an input @file{.def} file or in
4075 @samp{.drectve} sections in the input object files. This is the default
4076 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4077 attributes in the source code.
4078
4079 @item --exclude-symbols @var{list}
4080 Do not export the symbols in @var{list}. This is a list of symbol names
4081 separated by comma or colon characters. The symbol names should not
4082 contain a leading underscore. This is only meaningful when
4083 @option{--export-all-symbols} is used.
4084
4085 @item --no-default-excludes
4086 When @option{--export-all-symbols} is used, it will by default avoid
4087 exporting certain special symbols. The current list of symbols to avoid
4088 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4089 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4090 to go ahead and export these special symbols. This is only meaningful
4091 when @option{--export-all-symbols} is used.
4092
4093 @item -S @var{path}
4094 @itemx --as @var{path}
4095 Specifies the path, including the filename, of the assembler to be used
4096 to create the exports file.
4097
4098 @item -f @var{options}
4099 @itemx --as-flags @var{options}
4100 Specifies any specific command line options to be passed to the
4101 assembler when building the exports file. This option will work even if
4102 the @option{-S} option is not used. This option only takes one argument,
4103 and if it occurs more than once on the command line, then later
4104 occurrences will override earlier occurrences. So if it is necessary to
4105 pass multiple options to the assembler they should be enclosed in
4106 double quotes.
4107
4108 @item -D @var{name}
4109 @itemx --dll-name @var{name}
4110 Specifies the name to be stored in the @file{.def} file as the name of
4111 the DLL when the @option{-e} option is used. If this option is not
4112 present, then the filename given to the @option{-e} option will be
4113 used as the name of the DLL.
4114
4115 @item -m @var{machine}
4116 @itemx -machine @var{machine}
4117 Specifies the type of machine for which the library file should be
4118 built. @command{dlltool} has a built in default type, depending upon how
4119 it was created, but this option can be used to override that. This is
4120 normally only useful when creating DLLs for an ARM processor, when the
4121 contents of the DLL are actually encode using Thumb instructions.
4122
4123 @item -a
4124 @itemx --add-indirect
4125 Specifies that when @command{dlltool} is creating the exports file it
4126 should add a section which allows the exported functions to be
4127 referenced without using the import library. Whatever the hell that
4128 means!
4129
4130 @item -U
4131 @itemx --add-underscore
4132 Specifies that when @command{dlltool} is creating the exports file it
4133 should prepend an underscore to the names of @emph{all} exported symbols.
4134
4135 @item --no-leading-underscore
4136 @item --leading-underscore
4137 Specifies whether standard symbol should be forced to be prefixed, or
4138 not.
4139
4140 @item --add-stdcall-underscore
4141 Specifies that when @command{dlltool} is creating the exports file it
4142 should prepend an underscore to the names of exported @emph{stdcall}
4143 functions. Variable names and non-stdcall function names are not modified.
4144 This option is useful when creating GNU-compatible import libs for third
4145 party DLLs that were built with MS-Windows tools.
4146
4147 @item -k
4148 @itemx --kill-at
4149 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4150 of stdcall functions that will be imported from the DLL. This is
4151 useful when creating an import library for a DLL which exports stdcall
4152 functions but without the usual @samp{@@<number>} symbol name suffix.
4153
4154 This does not change the naming of symbols provided by the import library
4155 to programs linked against it, but only the entries in the import table
4156 (ie the .idata section).
4157
4158 @item -A
4159 @itemx --add-stdcall-alias
4160 Specifies that when @command{dlltool} is creating the exports file it
4161 should add aliases for stdcall symbols without @samp{@@ <number>}
4162 in addition to the symbols with @samp{@@ <number>}.
4163
4164 @item -p
4165 @itemx --ext-prefix-alias @var{prefix}
4166 Causes @command{dlltool} to create external aliases for all DLL
4167 imports with the specified prefix. The aliases are created for both
4168 external and import symbols with no leading underscore.
4169
4170 @item -x
4171 @itemx --no-idata4
4172 Specifies that when @command{dlltool} is creating the exports and library
4173 files it should omit the @code{.idata4} section. This is for compatibility
4174 with certain operating systems.
4175
4176 @item --use-nul-prefixed-import-tables
4177 Specifies that when @command{dlltool} is creating the exports and library
4178 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4179 element. This emulates old gnu import library generation of
4180 @code{dlltool}. By default this option is turned off.
4181
4182 @item -c
4183 @itemx --no-idata5
4184 Specifies that when @command{dlltool} is creating the exports and library
4185 files it should omit the @code{.idata5} section. This is for compatibility
4186 with certain operating systems.
4187
4188 @item -I @var{filename}
4189 @itemx --identify @var{filename}
4190 Specifies that @command{dlltool} should inspect the import library
4191 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4192 of the associated DLL(s). This can be performed in addition to any
4193 other operations indicated by the other options and arguments.
4194 @command{dlltool} fails if the import library does not exist or is not
4195 actually an import library. See also @option{--identify-strict}.
4196
4197 @item --identify-strict
4198 Modifies the behavior of the @option{--identify} option, such
4199 that an error is reported if @var{filename} is associated with
4200 more than one DLL.
4201
4202 @item -i
4203 @itemx --interwork
4204 Specifies that @command{dlltool} should mark the objects in the library
4205 file and exports file that it produces as supporting interworking
4206 between ARM and Thumb code.
4207
4208 @item -n
4209 @itemx --nodelete
4210 Makes @command{dlltool} preserve the temporary assembler files it used to
4211 create the exports file. If this option is repeated then dlltool will
4212 also preserve the temporary object files it uses to create the library
4213 file.
4214
4215 @item -t @var{prefix}
4216 @itemx --temp-prefix @var{prefix}
4217 Makes @command{dlltool} use @var{prefix} when constructing the names of
4218 temporary assembler and object files. By default, the temp file prefix
4219 is generated from the pid.
4220
4221 @item -v
4222 @itemx --verbose
4223 Make dlltool describe what it is doing.
4224
4225 @item -h
4226 @itemx --help
4227 Displays a list of command line options and then exits.
4228
4229 @item -V
4230 @itemx --version
4231 Displays dlltool's version number and then exits.
4232
4233 @end table
4234
4235 @c man end
4236
4237 @menu
4238 * def file format:: The format of the dlltool @file{.def} file
4239 @end menu
4240
4241 @node def file format
4242 @section The format of the @command{dlltool} @file{.def} file
4243
4244 A @file{.def} file contains any number of the following commands:
4245
4246 @table @asis
4247
4248 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4249 The result is going to be named @var{name}@code{.exe}.
4250
4251 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4252 The result is going to be named @var{name}@code{.dll}.
4253 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4254 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4255 details).
4256
4257 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4258 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4259 Declares @var{name1} as an exported symbol from the DLL, with optional
4260 ordinal number @var{integer}, or declares @var{name1} as an alias
4261 (forward) of the function @var{external-name} in the DLL.
4262 If @var{its_name} is specified, this name is used as string in export table.
4263 @var{module-name}.
4264 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4265 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4266 If you want to use LIBRARY as name then you need to quote it.
4267
4268 @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{]} *}
4269 Declares that @var{external-name} or the exported function whose
4270 ordinal number is @var{integer} is to be imported from the file
4271 @var{module-name}. If @var{internal-name} is specified then this is
4272 the name that the imported function will be referred to in the body of
4273 the DLL.
4274 If @var{its_name} is specified, this name is used as string in import table.
4275 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4276 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4277 If you want to use LIBRARY as name then you need to quote it.
4278
4279 @item @code{DESCRIPTION} @var{string}
4280 Puts @var{string} into the output @file{.exp} file in the
4281 @code{.rdata} section.
4282
4283 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4284 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4285 Generates @code{--stack} or @code{--heap}
4286 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4287 section. The linker will see this and act upon it.
4288
4289 @item @code{CODE} @var{attr} @code{+}
4290 @item @code{DATA} @var{attr} @code{+}
4291 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4292 Generates @code{--attr} @var{section-name} @var{attr} in the output
4293 @code{.drectve} section, where @var{attr} is one of @code{READ},
4294 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4295 this and act upon it.
4296
4297 @end table
4298
4299 @ignore
4300 @c man begin SEEALSO dlltool
4301 The Info pages for @file{binutils}.
4302 @c man end
4303 @end ignore
4304
4305 @node readelf
4306 @chapter readelf
4307
4308 @cindex ELF file information
4309 @kindex readelf
4310
4311 @c man title readelf Displays information about ELF files.
4312
4313 @smallexample
4314 @c man begin SYNOPSIS readelf
4315 readelf [@option{-a}|@option{--all}]
4316 [@option{-h}|@option{--file-header}]
4317 [@option{-l}|@option{--program-headers}|@option{--segments}]
4318 [@option{-S}|@option{--section-headers}|@option{--sections}]
4319 [@option{-g}|@option{--section-groups}]
4320 [@option{-t}|@option{--section-details}]
4321 [@option{-e}|@option{--headers}]
4322 [@option{-s}|@option{--syms}|@option{--symbols}]
4323 [@option{--dyn-syms}]
4324 [@option{-n}|@option{--notes}]
4325 [@option{-r}|@option{--relocs}]
4326 [@option{-u}|@option{--unwind}]
4327 [@option{-d}|@option{--dynamic}]
4328 [@option{-V}|@option{--version-info}]
4329 [@option{-A}|@option{--arch-specific}]
4330 [@option{-D}|@option{--use-dynamic}]
4331 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4332 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4333 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4334 [@option{-c}|@option{--archive-index}]
4335 [@option{-w[lLiaprmfFsoRt]}|
4336 @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]]
4337 [@option{--dwarf-depth=@var{n}}]
4338 [@option{--dwarf-start=@var{n}}]
4339 [@option{-I}|@option{--histogram}]
4340 [@option{-v}|@option{--version}]
4341 [@option{-W}|@option{--wide}]
4342 [@option{-H}|@option{--help}]
4343 @var{elffile}@dots{}
4344 @c man end
4345 @end smallexample
4346
4347 @c man begin DESCRIPTION readelf
4348
4349 @command{readelf} displays information about one or more ELF format object
4350 files. The options control what particular information to display.
4351
4352 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4353 64-bit ELF files are supported, as are archives containing ELF files.
4354
4355 This program performs a similar function to @command{objdump} but it
4356 goes into more detail and it exists independently of the @sc{bfd}
4357 library, so if there is a bug in @sc{bfd} then readelf will not be
4358 affected.
4359
4360 @c man end
4361
4362 @c man begin OPTIONS readelf
4363
4364 The long and short forms of options, shown here as alternatives, are
4365 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4366 given.
4367
4368 @table @env
4369 @item -a
4370 @itemx --all
4371 Equivalent to specifying @option{--file-header},
4372 @option{--program-headers}, @option{--sections}, @option{--symbols},
4373 @option{--relocs}, @option{--dynamic}, @option{--notes} and
4374 @option{--version-info}.
4375
4376 @item -h
4377 @itemx --file-header
4378 @cindex ELF file header information
4379 Displays the information contained in the ELF header at the start of the
4380 file.
4381
4382 @item -l
4383 @itemx --program-headers
4384 @itemx --segments
4385 @cindex ELF program header information
4386 @cindex ELF segment information
4387 Displays the information contained in the file's segment headers, if it
4388 has any.
4389
4390 @item -S
4391 @itemx --sections
4392 @itemx --section-headers
4393 @cindex ELF section information
4394 Displays the information contained in the file's section headers, if it
4395 has any.
4396
4397 @item -g
4398 @itemx --section-groups
4399 @cindex ELF section group information
4400 Displays the information contained in the file's section groups, if it
4401 has any.
4402
4403 @item -t
4404 @itemx --section-details
4405 @cindex ELF section information
4406 Displays the detailed section information. Implies @option{-S}.
4407
4408 @item -s
4409 @itemx --symbols
4410 @itemx --syms
4411 @cindex ELF symbol table information
4412 Displays the entries in symbol table section of the file, if it has one.
4413
4414 @item --dyn-syms
4415 @cindex ELF dynamic symbol table information
4416 Displays the entries in dynamic symbol table section of the file, if it
4417 has one.
4418
4419 @item -e
4420 @itemx --headers
4421 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4422
4423 @item -n
4424 @itemx --notes
4425 @cindex ELF notes
4426 Displays the contents of the NOTE segments and/or sections, if any.
4427
4428 @item -r
4429 @itemx --relocs
4430 @cindex ELF reloc information
4431 Displays the contents of the file's relocation section, if it has one.
4432
4433 @item -u
4434 @itemx --unwind
4435 @cindex unwind information
4436 Displays the contents of the file's unwind section, if it has one. Only
4437 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4438 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4439
4440 @item -d
4441 @itemx --dynamic
4442 @cindex ELF dynamic section information
4443 Displays the contents of the file's dynamic section, if it has one.
4444
4445 @item -V
4446 @itemx --version-info
4447 @cindex ELF version sections information
4448 Displays the contents of the version sections in the file, it they
4449 exist.
4450
4451 @item -A
4452 @itemx --arch-specific
4453 Displays architecture-specific information in the file, if there
4454 is any.
4455
4456 @item -D
4457 @itemx --use-dynamic
4458 When displaying symbols, this option makes @command{readelf} use the
4459 symbol hash tables in the file's dynamic section, rather than the
4460 symbol table sections.
4461
4462 @item -x <number or name>
4463 @itemx --hex-dump=<number or name>
4464 Displays the contents of the indicated section as a hexadecimal bytes.
4465 A number identifies a particular section by index in the section table;
4466 any other string identifies all sections with that name in the object file.
4467
4468 @item -R <number or name>
4469 @itemx --relocated-dump=<number or name>
4470 Displays the contents of the indicated section as a hexadecimal
4471 bytes. A number identifies a particular section by index in the
4472 section table; any other string identifies all sections with that name
4473 in the object file. The contents of the section will be relocated
4474 before they are displayed.
4475
4476 @item -p <number or name>
4477 @itemx --string-dump=<number or name>
4478 Displays the contents of the indicated section as printable strings.
4479 A number identifies a particular section by index in the section table;
4480 any other string identifies all sections with that name in the object file.
4481
4482 @item -c
4483 @itemx --archive-index
4484 @cindex Archive file symbol index information
4485 Displays the file symbol index information contained in the header part
4486 of binary archives. Performs the same function as the @option{t}
4487 command to @command{ar}, but without using the BFD library. @xref{ar}.
4488
4489 @item -w[lLiaprmfFsoRt]
4490 @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]
4491 Displays the contents of the debug sections in the file, if any are
4492 present. If one of the optional letters or words follows the switch
4493 then only data found in those specific sections will be dumped.
4494
4495 Note that there is no single letter option to display the content of
4496 trace sections or .gdb_index.
4497
4498 Note: the @option{=decodedline} option will display the interpreted
4499 contents of a .debug_line section whereas the @option{=rawline} option
4500 dumps the contents in a raw format.
4501
4502 Note: the @option{=frames-interp} option will display the interpreted
4503 contents of a .debug_frame section whereas the @option{=frames} option
4504 dumps the contents in a raw format.
4505
4506 Note: the output from the @option{=info} option can also be affected
4507 by the options @option{--dwarf-depth} and @option{--dwarf-start}.
4508
4509 @item --dwarf-depth=@var{n}
4510 Limit the dump of the @code{.debug_info} section to @var{n} children.
4511 This is only useful with @option{--debug-dump=info}. The default is
4512 to print all DIEs; the special value 0 for @var{n} will also have this
4513 effect.
4514
4515 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
4516 levels will not be printed. The range for @var{n} is zero-based.
4517
4518 @item --dwarf-start=@var{n}
4519 Print only DIEs beginning with the DIE numbered @var{n}. This is only
4520 useful with @option{--debug-dump=info}.
4521
4522 If specified, this option will suppress printing of any header
4523 information and all DIEs before the DIE numbered @var{n}. Only
4524 siblings and children of the specified DIE will be printed.
4525
4526 This can be used in conjunction with @option{--dwarf-depth}.
4527
4528 @item -I
4529 @itemx --histogram
4530 Display a histogram of bucket list lengths when displaying the contents
4531 of the symbol tables.
4532
4533 @item -v
4534 @itemx --version
4535 Display the version number of readelf.
4536
4537 @item -W
4538 @itemx --wide
4539 Don't break output lines to fit into 80 columns. By default
4540 @command{readelf} breaks section header and segment listing lines for
4541 64-bit ELF files, so that they fit into 80 columns. This option causes
4542 @command{readelf} to print each section header resp. each segment one a
4543 single line, which is far more readable on terminals wider than 80 columns.
4544
4545 @item -H
4546 @itemx --help
4547 Display the command line options understood by @command{readelf}.
4548
4549 @end table
4550
4551 @c man end
4552
4553 @ignore
4554 @c man begin SEEALSO readelf
4555 objdump(1), and the Info entries for @file{binutils}.
4556 @c man end
4557 @end ignore
4558
4559 @node elfedit
4560 @chapter elfedit
4561
4562 @cindex Update ELF header
4563 @kindex elfedit
4564
4565 @c man title elfedit Update the ELF header of ELF files.
4566
4567 @smallexample
4568 @c man begin SYNOPSIS elfedit
4569 elfedit [@option{--input-mach=}@var{machine}]
4570 [@option{--input-type=}@var{type}]
4571 [@option{--input-osabi=}@var{osabi}]
4572 @option{--output-mach=}@var{machine}
4573 @option{--output-type=}@var{type}
4574 @option{--output-osabi=}@var{osabi}
4575 [@option{-v}|@option{--version}]
4576 [@option{-h}|@option{--help}]
4577 @var{elffile}@dots{}
4578 @c man end
4579 @end smallexample
4580
4581 @c man begin DESCRIPTION elfedit
4582
4583 @command{elfedit} updates the ELF header of ELF files which have
4584 the matching ELF machine and file types. The options control how and
4585 which fields in the ELF header should be updated.
4586
4587 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4588 64-bit ELF files are supported, as are archives containing ELF files.
4589 @c man end
4590
4591 @c man begin OPTIONS elfedit
4592
4593 The long and short forms of options, shown here as alternatives, are
4594 equivalent. At least one of the @option{--output-mach},
4595 @option{--output-type} and @option{--output-osabi} options must be given.
4596
4597 @table @env
4598
4599 @item --input-mach=@var{machine}
4600 Set the matching input ELF machine type to @var{machine}. If
4601 @option{--input-mach} isn't specified, it will match any ELF
4602 machine types.
4603
4604 The supported ELF machine types are, @var{L1OM}, @var{K1OM} and
4605 @var{x86-64}.
4606
4607 @item --output-mach=@var{machine}
4608 Change the ELF machine type in the ELF header to @var{machine}. The
4609 supported ELF machine types are the same as @option{--input-mach}.
4610
4611 @item --input-type=@var{type}
4612 Set the matching input ELF file type to @var{type}. If
4613 @option{--input-type} isn't specified, it will match any ELF file types.
4614
4615 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4616
4617 @item --output-type=@var{type}
4618 Change the ELF file type in the ELF header to @var{type}. The
4619 supported ELF types are the same as @option{--input-type}.
4620
4621 @item --input-osabi=@var{osabi}
4622 Set the matching input ELF file OSABI to @var{osabi}. If
4623 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4624
4625 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4626 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4627 @var{Solaris}, @var{AIX}, @var{Irix},
4628 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4629 @var{NSK}, @var{AROS} and @var{FenixOS}.
4630
4631 @item --output-osabi=@var{osabi}
4632 Change the ELF OSABI in the ELF header to @var{osabi}. The
4633 supported ELF OSABI are the same as @option{--input-osabi}.
4634
4635 @item -v
4636 @itemx --version
4637 Display the version number of @command{elfedit}.
4638
4639 @item -h
4640 @itemx --help
4641 Display the command line options understood by @command{elfedit}.
4642
4643 @end table
4644
4645 @c man end
4646
4647 @ignore
4648 @c man begin SEEALSO elfedit
4649 readelf(1), and the Info entries for @file{binutils}.
4650 @c man end
4651 @end ignore
4652
4653 @node Common Options
4654 @chapter Common Options
4655
4656 The following command-line options are supported by all of the
4657 programs described in this manual.
4658
4659 @c man begin OPTIONS
4660 @table @env
4661 @include at-file.texi
4662 @c man end
4663
4664 @item --help
4665 Display the command-line options supported by the program.
4666
4667 @item --version
4668 Display the version number of the program.
4669
4670 @c man begin OPTIONS
4671 @end table
4672 @c man end
4673
4674 @node Selecting the Target System
4675 @chapter Selecting the Target System
4676
4677 You can specify two aspects of the target system to the @sc{gnu}
4678 binary file utilities, each in several ways:
4679
4680 @itemize @bullet
4681 @item
4682 the target
4683
4684 @item
4685 the architecture
4686 @end itemize
4687
4688 In the following summaries, the lists of ways to specify values are in
4689 order of decreasing precedence. The ways listed first override those
4690 listed later.
4691
4692 The commands to list valid values only list the values for which the
4693 programs you are running were configured. If they were configured with
4694 @option{--enable-targets=all}, the commands list most of the available
4695 values, but a few are left out; not all targets can be configured in at
4696 once because some of them can only be configured @dfn{native} (on hosts
4697 with the same type as the target system).
4698
4699 @menu
4700 * Target Selection::
4701 * Architecture Selection::
4702 @end menu
4703
4704 @node Target Selection
4705 @section Target Selection
4706
4707 A @dfn{target} is an object file format. A given target may be
4708 supported for multiple architectures (@pxref{Architecture Selection}).
4709 A target selection may also have variations for different operating
4710 systems or architectures.
4711
4712 The command to list valid target values is @samp{objdump -i}
4713 (the first column of output contains the relevant information).
4714
4715 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4716 @samp{a.out-sunos-big}.
4717
4718 You can also specify a target using a configuration triplet. This is
4719 the same sort of name that is passed to @file{configure} to specify a
4720 target. When you use a configuration triplet as an argument, it must be
4721 fully canonicalized. You can see the canonical version of a triplet by
4722 running the shell script @file{config.sub} which is included with the
4723 sources.
4724
4725 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4726 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4727
4728 @subheading @command{objdump} Target
4729
4730 Ways to specify:
4731
4732 @enumerate
4733 @item
4734 command line option: @option{-b} or @option{--target}
4735
4736 @item
4737 environment variable @code{GNUTARGET}
4738
4739 @item
4740 deduced from the input file
4741 @end enumerate
4742
4743 @subheading @command{objcopy} and @command{strip} Input Target
4744
4745 Ways to specify:
4746
4747 @enumerate
4748 @item
4749 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
4750
4751 @item
4752 environment variable @code{GNUTARGET}
4753
4754 @item
4755 deduced from the input file
4756 @end enumerate
4757
4758 @subheading @command{objcopy} and @command{strip} Output Target
4759
4760 Ways to specify:
4761
4762 @enumerate
4763 @item
4764 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
4765
4766 @item
4767 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
4768
4769 @item
4770 environment variable @code{GNUTARGET}
4771
4772 @item
4773 deduced from the input file
4774 @end enumerate
4775
4776 @subheading @command{nm}, @command{size}, and @command{strings} Target
4777
4778 Ways to specify:
4779
4780 @enumerate
4781 @item
4782 command line option: @option{--target}
4783
4784 @item
4785 environment variable @code{GNUTARGET}
4786
4787 @item
4788 deduced from the input file
4789 @end enumerate
4790
4791 @node Architecture Selection
4792 @section Architecture Selection
4793
4794 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4795 to run. Its name may contain a colon, separating the name of the
4796 processor family from the name of the particular @sc{cpu}.
4797
4798 The command to list valid architecture values is @samp{objdump -i} (the
4799 second column contains the relevant information).
4800
4801 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4802
4803 @subheading @command{objdump} Architecture
4804
4805 Ways to specify:
4806
4807 @enumerate
4808 @item
4809 command line option: @option{-m} or @option{--architecture}
4810
4811 @item
4812 deduced from the input file
4813 @end enumerate
4814
4815 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4816
4817 Ways to specify:
4818
4819 @enumerate
4820 @item
4821 deduced from the input file
4822 @end enumerate
4823
4824 @node Reporting Bugs
4825 @chapter Reporting Bugs
4826 @cindex bugs
4827 @cindex reporting bugs
4828
4829 Your bug reports play an essential role in making the binary utilities
4830 reliable.
4831
4832 Reporting a bug may help you by bringing a solution to your problem, or
4833 it may not. But in any case the principal function of a bug report is
4834 to help the entire community by making the next version of the binary
4835 utilities work better. Bug reports are your contribution to their
4836 maintenance.
4837
4838 In order for a bug report to serve its purpose, you must include the
4839 information that enables us to fix the bug.
4840
4841 @menu
4842 * Bug Criteria:: Have you found a bug?
4843 * Bug Reporting:: How to report bugs
4844 @end menu
4845
4846 @node Bug Criteria
4847 @section Have You Found a Bug?
4848 @cindex bug criteria
4849
4850 If you are not sure whether you have found a bug, here are some guidelines:
4851
4852 @itemize @bullet
4853 @cindex fatal signal
4854 @cindex crash
4855 @item
4856 If a binary utility gets a fatal signal, for any input whatever, that is
4857 a bug. Reliable utilities never crash.
4858
4859 @cindex error on valid input
4860 @item
4861 If a binary utility produces an error message for valid input, that is a
4862 bug.
4863
4864 @item
4865 If you are an experienced user of binary utilities, your suggestions for
4866 improvement are welcome in any case.
4867 @end itemize
4868
4869 @node Bug Reporting
4870 @section How to Report Bugs
4871 @cindex bug reports
4872 @cindex bugs, reporting
4873
4874 A number of companies and individuals offer support for @sc{gnu}
4875 products. If you obtained the binary utilities from a support
4876 organization, we recommend you contact that organization first.
4877
4878 You can find contact information for many support companies and
4879 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
4880 distribution.
4881
4882 @ifset BUGURL
4883 In any event, we also recommend that you send bug reports for the binary
4884 utilities to @value{BUGURL}.
4885 @end ifset
4886
4887 The fundamental principle of reporting bugs usefully is this:
4888 @strong{report all the facts}. If you are not sure whether to state a
4889 fact or leave it out, state it!
4890
4891 Often people omit facts because they think they know what causes the
4892 problem and assume that some details do not matter. Thus, you might
4893 assume that the name of a file you use in an example does not matter.
4894 Well, probably it does not, but one cannot be sure. Perhaps the bug is
4895 a stray memory reference which happens to fetch from the location where
4896 that pathname is stored in memory; perhaps, if the pathname were
4897 different, the contents of that location would fool the utility into
4898 doing the right thing despite the bug. Play it safe and give a
4899 specific, complete example. That is the easiest thing for you to do,
4900 and the most helpful.
4901
4902 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
4903 it is new to us. Therefore, always write your bug reports on the assumption
4904 that the bug has not been reported previously.
4905
4906 Sometimes people give a few sketchy facts and ask, ``Does this ring a
4907 bell?'' This cannot help us fix a bug, so it is basically useless. We
4908 respond by asking for enough details to enable us to investigate.
4909 You might as well expedite matters by sending them to begin with.
4910
4911 To enable us to fix the bug, you should include all these things:
4912
4913 @itemize @bullet
4914 @item
4915 The version of the utility. Each utility announces it if you start it
4916 with the @option{--version} argument.
4917
4918 Without this, we will not know whether there is any point in looking for
4919 the bug in the current version of the binary utilities.
4920
4921 @item
4922 Any patches you may have applied to the source, including any patches
4923 made to the @code{BFD} library.
4924
4925 @item
4926 The type of machine you are using, and the operating system name and
4927 version number.
4928
4929 @item
4930 What compiler (and its version) was used to compile the utilities---e.g.
4931 ``@code{gcc-2.7}''.
4932
4933 @item
4934 The command arguments you gave the utility to observe the bug. To
4935 guarantee you will not omit something important, list them all. A copy
4936 of the Makefile (or the output from make) is sufficient.
4937
4938 If we were to try to guess the arguments, we would probably guess wrong
4939 and then we might not encounter the bug.
4940
4941 @item
4942 A complete input file, or set of input files, that will reproduce the
4943 bug. If the utility is reading an object file or files, then it is
4944 generally most helpful to send the actual object files.
4945
4946 If the source files were produced exclusively using @sc{gnu} programs
4947 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
4948 may be OK to send the source files rather than the object files. In
4949 this case, be sure to say exactly what version of @command{gcc}, or
4950 whatever, was used to produce the object files. Also say how
4951 @command{gcc}, or whatever, was configured.
4952
4953 @item
4954 A description of what behavior you observe that you believe is
4955 incorrect. For example, ``It gets a fatal signal.''
4956
4957 Of course, if the bug is that the utility gets a fatal signal, then we
4958 will certainly notice it. But if the bug is incorrect output, we might
4959 not notice unless it is glaringly wrong. You might as well not give us
4960 a chance to make a mistake.
4961
4962 Even if the problem you experience is a fatal signal, you should still
4963 say so explicitly. Suppose something strange is going on, such as your
4964 copy of the utility is out of sync, or you have encountered a bug in
4965 the C library on your system. (This has happened!) Your copy might
4966 crash and ours would not. If you told us to expect a crash, then when
4967 ours fails to crash, we would know that the bug was not happening for
4968 us. If you had not told us to expect a crash, then we would not be able
4969 to draw any conclusion from our observations.
4970
4971 @item
4972 If you wish to suggest changes to the source, send us context diffs, as
4973 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
4974 option. Always send diffs from the old file to the new file. If you
4975 wish to discuss something in the @command{ld} source, refer to it by
4976 context, not by line number.
4977
4978 The line numbers in our development sources will not match those in your
4979 sources. Your line numbers would convey no useful information to us.
4980 @end itemize
4981
4982 Here are some things that are not necessary:
4983
4984 @itemize @bullet
4985 @item
4986 A description of the envelope of the bug.
4987
4988 Often people who encounter a bug spend a lot of time investigating
4989 which changes to the input file will make the bug go away and which
4990 changes will not affect it.
4991
4992 This is often time consuming and not very useful, because the way we
4993 will find the bug is by running a single example under the debugger
4994 with breakpoints, not by pure deduction from a series of examples.
4995 We recommend that you save your time for something else.
4996
4997 Of course, if you can find a simpler example to report @emph{instead}
4998 of the original one, that is a convenience for us. Errors in the
4999 output will be easier to spot, running under the debugger will take
5000 less time, and so on.
5001
5002 However, simplification is not vital; if you do not want to do this,
5003 report the bug anyway and send us the entire test case you used.
5004
5005 @item
5006 A patch for the bug.
5007
5008 A patch for the bug does help us if it is a good one. But do not omit
5009 the necessary information, such as the test case, on the assumption that
5010 a patch is all we need. We might see problems with your patch and decide
5011 to fix the problem another way, or we might not understand it at all.
5012
5013 Sometimes with programs as complicated as the binary utilities it is
5014 very hard to construct an example that will make the program follow a
5015 certain path through the code. If you do not send us the example, we
5016 will not be able to construct one, so we will not be able to verify that
5017 the bug is fixed.
5018
5019 And if we cannot understand what bug you are trying to fix, or why your
5020 patch should be an improvement, we will not install it. A test case will
5021 help us to understand.
5022
5023 @item
5024 A guess about what the bug is or what it depends on.
5025
5026 Such guesses are usually wrong. Even we cannot guess right about such
5027 things without first using the debugger to find the facts.
5028 @end itemize
5029
5030 @node GNU Free Documentation License
5031 @appendix GNU Free Documentation License
5032
5033 @include fdl.texi
5034
5035 @node Binutils Index
5036 @unnumbered Binutils Index
5037
5038 @printindex cp
5039
5040 @bye
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