1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2017 Free Software Foundation, Inc.
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''.
25 @dircategory Software development
27 * Binutils: (binutils). The GNU binary utilities.
30 @dircategory Individual utilities
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.
52 @title The @sc{gnu} Binary Utilities
53 @ifset VERSION_PACKAGE
54 @subtitle @value{VERSION_PACKAGE}
56 @subtitle Version @value{VERSION}
58 @subtitle @value{UPDATED}
59 @author Roland H. Pesch
60 @author Jeffrey M. Osier
61 @author Cygnus Support
65 {\parskip=0pt \hfill Cygnus Support\par \hfill
66 Texinfo \texinfoversion\par }
69 @vskip 0pt plus 1filll
78 This brief manual contains documentation for the @sc{gnu} binary
80 @ifset VERSION_PACKAGE
81 @value{VERSION_PACKAGE}
83 version @value{VERSION}:
88 Create, modify, and extract from archives
91 List symbols from object files
94 Copy and translate object files
97 Display information from object files
100 Generate index to archive contents
103 Display the contents of ELF format files.
106 List file section sizes and total size
109 List printable strings from files
115 Update the ELF header of ELF files.
118 Demangle encoded C++ symbols (on MS-DOS, this program is named
122 Convert addresses into file names and line numbers
125 Convert object code into a Netware Loadable Module
128 Manipulate Windows resources
131 Generator for Windows message resources
134 Create the files needed to build and use Dynamic Link Libraries
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''.
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
172 @cindex collections of files
174 @c man title ar create, modify, and extract from archives
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 ]
181 @c man begin DESCRIPTION ar
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).
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
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).
201 @command{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
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.
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.
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.
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.
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.
236 The paths to the elements of the archive are stored relative to the
239 @cindex compatibility, @command{ar}
240 @cindex @command{ar} compatibility
241 @sc{gnu} @command{ar} is designed to be compatible with two different
242 facilities. You can control its activity using command-line options,
243 like the different varieties of @command{ar} on Unix systems; or, if you
244 specify the single command-line option @option{-M}, you can control it
245 with a script supplied via standard input, like the MRI ``librarian''
251 * ar cmdline:: Controlling @command{ar} on the command line
252 * ar scripts:: Controlling @command{ar} with a script
257 @section Controlling @command{ar} on the Command Line
260 @c man begin SYNOPSIS ar
261 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{}]
265 @cindex Unix compatibility, @command{ar}
266 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
267 arguments to execute: one keyletter specifying the @emph{operation}
268 (optionally accompanied by other keyletters specifying
269 @emph{modifiers}), and the archive name to act on.
271 Most operations can also accept further @var{member} arguments,
272 specifying particular files to operate on.
274 @c man begin OPTIONS ar
276 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
277 flags @var{mod} in any order, within the first command-line argument.
279 If you wish, you may begin the first command-line argument with a
282 @cindex operations on archive
283 The @var{p} keyletter specifies what operation to execute; it may be
284 any of the following, but you must specify only one of them:
288 @cindex deleting from archive
289 @emph{Delete} modules from the archive. Specify the names of modules to
290 be deleted as @var{member}@dots{}; the archive is untouched if you
291 specify no files to delete.
293 If you specify the @samp{v} modifier, @command{ar} lists each module
297 @cindex moving in archive
298 Use this operation to @emph{move} members in an archive.
300 The ordering of members in an archive can make a difference in how
301 programs are linked using the library, if a symbol is defined in more
304 If no modifiers are used with @code{m}, any members you name in the
305 @var{member} arguments are moved to the @emph{end} of the archive;
306 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
307 specified place instead.
310 @cindex printing from archive
311 @emph{Print} the specified members of the archive, to the standard
312 output file. If the @samp{v} modifier is specified, show the member
313 name before copying its contents to standard output.
315 If you specify no @var{member} arguments, all the files in the archive are
319 @cindex quick append to archive
320 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
321 @var{archive}, without checking for replacement.
323 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
324 operation; new members are always placed at the end of the archive.
326 The modifier @samp{v} makes @command{ar} list each file as it is appended.
328 Since the point of this operation is speed, implementations of
329 @command{ar} have the option of not updating the archive's symbol
330 table if one exists. Too many different systems however assume that
331 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
332 rebuild the table even with a quick append.
334 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
335 synonym for @samp{r} - replacing already existing files in the
336 archive and appending new ones at the end.
339 @cindex replacement in archive
340 Insert the files @var{member}@dots{} into @var{archive} (with
341 @emph{replacement}). This operation differs from @samp{q} in that any
342 previously existing members are deleted if their names match those being
345 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
346 displays an error message, and leaves undisturbed any existing members
347 of the archive matching that name.
349 By default, new members are added at the end of the file; but you may
350 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
351 placement relative to some existing member.
353 The modifier @samp{v} used with this operation elicits a line of
354 output for each file inserted, along with one of the letters @samp{a} or
355 @samp{r} to indicate whether the file was appended (no old member
356 deleted) or replaced.
360 Add an index to the archive, or update it if it already exists. Note
361 this command is an exception to the rule that there can only be one
362 command letter, as it is possible to use it as either a command or a
363 modifier. In either case it does the same thing.
366 @cindex contents of archive
367 Display a @emph{table} listing the contents of @var{archive}, or those
368 of the files listed in @var{member}@dots{} that are present in the
369 archive. Normally only the member name is shown; if you also want to
370 see the modes (permissions), timestamp, owner, group, and size, you can
371 request that by also specifying the @samp{v} modifier.
373 If you do not specify a @var{member}, all files in the archive
376 @cindex repeated names in archive
377 @cindex name duplication in archive
378 If there is more than one file with the same name (say, @samp{fie}) in
379 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
380 first instance; to see them all, you must ask for a complete
381 listing---in our example, @samp{ar t b.a}.
382 @c WRS only; per Gumby, this is implementation-dependent, and in a more
383 @c recent case in fact works the other way.
386 @cindex extract from archive
387 @emph{Extract} members (named @var{member}) from the archive. You can
388 use the @samp{v} modifier with this operation, to request that
389 @command{ar} list each name as it extracts it.
391 If you do not specify a @var{member}, all files in the archive
394 Files cannot be extracted from a thin archive.
397 A number of modifiers (@var{mod}) may immediately follow the @var{p}
398 keyletter, to specify variations on an operation's behavior:
402 @cindex relative placement in archive
403 Add new files @emph{after} an existing member of the
404 archive. If you use the modifier @samp{a}, the name of an existing archive
405 member must be present as the @var{relpos} argument, before the
406 @var{archive} specification.
409 Add new files @emph{before} an existing member of the
410 archive. If you use the modifier @samp{b}, the name of an existing archive
411 member must be present as the @var{relpos} argument, before the
412 @var{archive} specification. (same as @samp{i}).
415 @cindex creating archives
416 @emph{Create} the archive. The specified @var{archive} is always
417 created if it did not exist, when you request an update. But a warning is
418 issued unless you specify in advance that you expect to create it, by
422 @cindex deterministic archives
423 @kindex --enable-deterministic-archives
424 Operate in @emph{deterministic} mode. When adding files and the archive
425 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
426 for all files. When this option is used, if @command{ar} is used with
427 identical options and identical input files, multiple runs will create
428 identical output files regardless of the input files' owners, groups,
429 file modes, or modification times.
431 If @file{binutils} was configured with
432 @option{--enable-deterministic-archives}, then this mode is on by default.
433 It can be disabled with the @samp{U} modifier, below.
436 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
437 names of any length. This will cause it to create archives which are
438 not compatible with the native @command{ar} program on some systems. If
439 this is a concern, the @samp{f} modifier may be used to truncate file
440 names when putting them in the archive.
443 Insert new files @emph{before} an existing member of the
444 archive. If you use the modifier @samp{i}, the name of an existing archive
445 member must be present as the @var{relpos} argument, before the
446 @var{archive} specification. (same as @samp{b}).
449 This modifier is accepted but not used.
450 @c whaffor ar l modifier??? presumably compat; with
451 @c what???---doc@@cygnus.com, 25jan91
454 Uses the @var{count} parameter. This is used if there are multiple
455 entries in the archive with the same name. Extract or delete instance
456 @var{count} of the given name from the archive.
459 @cindex dates in archive
460 Preserve the @emph{original} dates of members when extracting them. If
461 you do not specify this modifier, files extracted from the archive
462 are stamped with the time of extraction.
465 Use the full path name when matching names in the archive. @sc{gnu}
466 @command{ar} can not create an archive with a full path name (such archives
467 are not POSIX complaint), but other archive creators can. This option
468 will cause @sc{gnu} @command{ar} to match file names using a complete path
469 name, which can be convenient when extracting a single file from an
470 archive created by another tool.
473 @cindex writing archive index
474 Write an object-file index into the archive, or update an existing one,
475 even if no other change is made to the archive. You may use this modifier
476 flag either with any operation, or alone. Running @samp{ar s} on an
477 archive is equivalent to running @samp{ranlib} on it.
480 @cindex not writing archive index
481 Do not generate an archive symbol table. This can speed up building a
482 large library in several steps. The resulting archive can not be used
483 with the linker. In order to build a symbol table, you must omit the
484 @samp{S} modifier on the last execution of @samp{ar}, or you must run
485 @samp{ranlib} on the archive.
488 @cindex creating thin archive
489 Make the specified @var{archive} a @emph{thin} archive. If it already
490 exists and is a regular archive, the existing members must be present
491 in the same directory as @var{archive}.
494 @cindex updating an archive
495 Normally, @samp{ar r}@dots{} inserts all files
496 listed into the archive. If you would like to insert @emph{only} those
497 of the files you list that are newer than existing members of the same
498 names, use this modifier. The @samp{u} modifier is allowed only for the
499 operation @samp{r} (replace). In particular, the combination @samp{qu} is
500 not allowed, since checking the timestamps would lose any speed
501 advantage from the operation @samp{q}.
504 @cindex deterministic archives
505 @kindex --enable-deterministic-archives
506 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
507 of the @samp{D} modifier, above: added files and the archive index will
508 get their actual UID, GID, timestamp, and file mode values.
510 This is the default unless @file{binutils} was configured with
511 @option{--enable-deterministic-archives}.
514 This modifier requests the @emph{verbose} version of an operation. Many
515 operations display additional information, such as filenames processed,
516 when the modifier @samp{v} is appended.
519 This modifier shows the version number of @command{ar}.
522 The @command{ar} program also supports some command line options which
523 are neither modifiers nor actions, but which do change its behaviour
528 Displays the list of command line options supported by @command{ar}
532 Displays the version information of @command{ar} and then exits.
535 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
536 compatibility with AIX. The behaviour produced by this option is the
537 default for @sc{gnu} @command{ar}. @command{ar} does not support any
538 of the other @samp{-X} options; in particular, it does not support
539 @option{-X32} which is the default for AIX @command{ar}.
541 @item --plugin @var{name}
543 The optional command line switch @option{--plugin @var{name}} causes
544 @command{ar} to load the plugin called @var{name} which adds support
545 for more file formats, including object files with link-time
546 optimization information.
548 This option is only available if the toolchain has been built with
549 plugin support enabled.
551 If @option{--plugin} is not provided, but plugin support has been
552 enabled then @command{ar} iterates over the files in
553 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
554 plugin that claims the object in question is used.
556 Please note that this plugin search directory is @emph{not} the one
557 used by @command{ld}'s @option{-plugin} option. In order to make
558 @command{ar} use the linker plugin it must be copied into the
559 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
560 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
561 based compilations it is called @file{LLVMgold.so}. The GCC plugin
562 is always backwards compatible with earlier versions, so it is
563 sufficient to just copy the newest one.
565 @item --target @var{target}
566 The optional command line switch @option{--target @var{bfdname}}
567 specifies that the archive members are in an object code format
568 different from your system's default format. See
569 @xref{Target Selection}, for more information.
574 @c man begin SEEALSO ar
575 nm(1), ranlib(1), and the Info entries for @file{binutils}.
580 @section Controlling @command{ar} with a Script
583 ar -M [ <@var{script} ]
586 @cindex MRI compatibility, @command{ar}
587 @cindex scripts, @command{ar}
588 If you use the single command-line option @samp{-M} with @command{ar}, you
589 can control its operation with a rudimentary command language. This
590 form of @command{ar} operates interactively if standard input is coming
591 directly from a terminal. During interactive use, @command{ar} prompts for
592 input (the prompt is @samp{AR >}), and continues executing even after
593 errors. If you redirect standard input to a script file, no prompts are
594 issued, and @command{ar} abandons execution (with a nonzero exit code)
597 The @command{ar} command language is @emph{not} designed to be equivalent
598 to the command-line options; in fact, it provides somewhat less control
599 over archives. The only purpose of the command language is to ease the
600 transition to @sc{gnu} @command{ar} for developers who already have scripts
601 written for the MRI ``librarian'' program.
603 The syntax for the @command{ar} command language is straightforward:
606 commands are recognized in upper or lower case; for example, @code{LIST}
607 is the same as @code{list}. In the following descriptions, commands are
608 shown in upper case for clarity.
611 a single command may appear on each line; it is the first word on the
615 empty lines are allowed, and have no effect.
618 comments are allowed; text after either of the characters @samp{*}
619 or @samp{;} is ignored.
622 Whenever you use a list of names as part of the argument to an @command{ar}
623 command, you can separate the individual names with either commas or
624 blanks. Commas are shown in the explanations below, for clarity.
627 @samp{+} is used as a line continuation character; if @samp{+} appears
628 at the end of a line, the text on the following line is considered part
629 of the current command.
632 Here are the commands you can use in @command{ar} scripts, or when using
633 @command{ar} interactively. Three of them have special significance:
635 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
636 a temporary file required for most of the other commands.
638 @code{SAVE} commits the changes so far specified by the script. Prior
639 to @code{SAVE}, commands affect only the temporary copy of the current
643 @item ADDLIB @var{archive}
644 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
645 Add all the contents of @var{archive} (or, if specified, each named
646 @var{module} from @var{archive}) to the current archive.
648 Requires prior use of @code{OPEN} or @code{CREATE}.
650 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
651 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
652 @c else like "ar q..."
653 Add each named @var{member} as a module in the current archive.
655 Requires prior use of @code{OPEN} or @code{CREATE}.
658 Discard the contents of the current archive, canceling the effect of
659 any operations since the last @code{SAVE}. May be executed (with no
660 effect) even if no current archive is specified.
662 @item CREATE @var{archive}
663 Creates an archive, and makes it the current archive (required for many
664 other commands). The new archive is created with a temporary name; it
665 is not actually saved as @var{archive} until you use @code{SAVE}.
666 You can overwrite existing archives; similarly, the contents of any
667 existing file named @var{archive} will not be destroyed until @code{SAVE}.
669 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
670 Delete each listed @var{module} from the current archive; equivalent to
671 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
673 Requires prior use of @code{OPEN} or @code{CREATE}.
675 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
676 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
677 List each named @var{module} present in @var{archive}. The separate
678 command @code{VERBOSE} specifies the form of the output: when verbose
679 output is off, output is like that of @samp{ar -t @var{archive}
680 @var{module}@dots{}}. When verbose output is on, the listing is like
681 @samp{ar -tv @var{archive} @var{module}@dots{}}.
683 Output normally goes to the standard output stream; however, if you
684 specify @var{outputfile} as a final argument, @command{ar} directs the
688 Exit from @command{ar}, with a @code{0} exit code to indicate successful
689 completion. This command does not save the output file; if you have
690 changed the current archive since the last @code{SAVE} command, those
693 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
694 Extract each named @var{module} from the current archive, writing them
695 into the current directory as separate files. Equivalent to @samp{ar -x
696 @var{archive} @var{module}@dots{}}.
698 Requires prior use of @code{OPEN} or @code{CREATE}.
701 @c FIXME Tokens but no commands???
708 Display full contents of the current archive, in ``verbose'' style
709 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
710 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
711 enhancement, rather than present for MRI compatibility.)
713 Requires prior use of @code{OPEN} or @code{CREATE}.
715 @item OPEN @var{archive}
716 Opens an existing archive for use as the current archive (required for
717 many other commands). Any changes as the result of subsequent commands
718 will not actually affect @var{archive} until you next use @code{SAVE}.
720 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
721 In the current archive, replace each existing @var{module} (named in
722 the @code{REPLACE} arguments) from files in the current working directory.
723 To execute this command without errors, both the file, and the module in
724 the current archive, must exist.
726 Requires prior use of @code{OPEN} or @code{CREATE}.
729 Toggle an internal flag governing the output from @code{DIRECTORY}.
730 When the flag is on, @code{DIRECTORY} output matches output from
731 @samp{ar -tv }@dots{}.
734 Commit your changes to the current archive, and actually save it as a
735 file with the name specified in the last @code{CREATE} or @code{OPEN}
738 Requires prior use of @code{OPEN} or @code{CREATE}.
747 The @sc{gnu} linker @command{ld} is now described in a separate manual.
748 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
756 @c man title nm list symbols from object files
759 @c man begin SYNOPSIS nm
760 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
761 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
762 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
763 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
764 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
765 [@option{-n}|@option{-v}|@option{--numeric-sort}]
766 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
767 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
768 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
769 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
770 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
771 [@option{--plugin} @var{name}] [@option{--size-sort}] [@option{--special-syms}]
772 [@option{--synthetic}] [@option{--with-symbol-versions}] [@option{--target=}@var{bfdname}]
773 [@var{objfile}@dots{}]
777 @c man begin DESCRIPTION nm
778 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
779 If no object files are listed as arguments, @command{nm} assumes the file
782 For each symbol, @command{nm} shows:
786 The symbol value, in the radix selected by options (see below), or
787 hexadecimal by default.
790 The symbol type. At least the following types are used; others are, as
791 well, depending on the object file format. If lowercase, the symbol is
792 usually local; if uppercase, the symbol is global (external). There
793 are however a few lowercase symbols that are shown for special global
794 symbols (@code{u}, @code{v} and @code{w}).
796 @c Some more detail on exactly what these symbol types are used for
800 The symbol's value is absolute, and will not be changed by further
805 The symbol is in the uninitialized data section (known as BSS).
808 The symbol is common. Common symbols are uninitialized data. When
809 linking, multiple common symbols may appear with the same name. If the
810 symbol is defined anywhere, the common symbols are treated as undefined
813 For more details on common symbols, see the discussion of
814 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
819 The symbol is in the initialized data section.
823 The symbol is in an initialized data section for small objects. Some
824 object file formats permit more efficient access to small data objects,
825 such as a global int variable as opposed to a large global array.
828 For PE format files this indicates that the symbol is in a section
829 specific to the implementation of DLLs. For ELF format files this
830 indicates that the symbol is an indirect function. This is a GNU
831 extension to the standard set of ELF symbol types. It indicates a
832 symbol which if referenced by a relocation does not evaluate to its
833 address, but instead must be invoked at runtime. The runtime
834 execution will then return the value to be used in the relocation.
837 The symbol is an indirect reference to another symbol.
840 The symbol is a debugging symbol.
843 The symbols is in a stack unwind section.
847 The symbol is in a read only data section.
851 The symbol is in an uninitialized data section for small objects.
855 The symbol is in the text (code) section.
858 The symbol is undefined.
861 The symbol is a unique global symbol. This is a GNU extension to the
862 standard set of ELF symbol bindings. For such a symbol the dynamic linker
863 will make sure that in the entire process there is just one symbol with
864 this name and type in use.
868 The symbol is a weak object. When a weak defined symbol is linked with
869 a normal defined symbol, the normal defined symbol is used with no error.
870 When a weak undefined symbol is linked and the symbol is not defined,
871 the value of the weak symbol becomes zero with no error. On some
872 systems, uppercase indicates that a default value has been specified.
876 The symbol is a weak symbol that has not been specifically tagged as a
877 weak object symbol. When a weak defined symbol is linked with a normal
878 defined symbol, the normal defined symbol is used with no error.
879 When a weak undefined symbol is linked and the symbol is not defined,
880 the value of the symbol is determined in a system-specific manner without
881 error. On some systems, uppercase indicates that a default value has been
885 The symbol is a stabs symbol in an a.out object file. In this case, the
886 next values printed are the stabs other field, the stabs desc field, and
887 the stab type. Stabs symbols are used to hold debugging information.
890 The symbol type is unknown, or object file format specific.
899 @c man begin OPTIONS nm
900 The long and short forms of options, shown here as alternatives, are
906 @itemx --print-file-name
907 @cindex input file name
909 @cindex source file name
910 Precede each symbol by the name of the input file (or archive member)
911 in which it was found, rather than identifying the input file once only,
912 before all of its symbols.
916 @cindex debugging symbols
917 Display all symbols, even debugger-only symbols; normally these are not
921 @cindex @command{nm} format
922 @cindex @command{nm} compatibility
923 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
926 @itemx --demangle[=@var{style}]
927 @cindex demangling in nm
928 Decode (@dfn{demangle}) low-level symbol names into user-level names.
929 Besides removing any initial underscore prepended by the system, this
930 makes C++ function names readable. Different compilers have different
931 mangling styles. The optional demangling style argument can be used to
932 choose an appropriate demangling style for your compiler. @xref{c++filt},
933 for more information on demangling.
936 Do not demangle low-level symbol names. This is the default.
940 @cindex dynamic symbols
941 Display the dynamic symbols rather than the normal symbols. This is
942 only meaningful for dynamic objects, such as certain types of shared
945 @item -f @var{format}
946 @itemx --format=@var{format}
947 @cindex @command{nm} format
948 @cindex @command{nm} compatibility
949 Use the output format @var{format}, which can be @code{bsd},
950 @code{sysv}, or @code{posix}. The default is @code{bsd}.
951 Only the first character of @var{format} is significant; it can be
952 either upper or lower case.
956 @cindex external symbols
957 Display only external symbols.
961 Show a summary of the options to @command{nm} and exit.
964 @itemx --line-numbers
965 @cindex symbol line numbers
966 For each symbol, use debugging information to try to find a filename and
967 line number. For a defined symbol, look for the line number of the
968 address of the symbol. For an undefined symbol, look for the line
969 number of a relocation entry which refers to the symbol. If line number
970 information can be found, print it after the other symbol information.
973 @cindex objdump inlines
974 When option @option{-l} is active, if the address belongs to a
975 function that was inlined, then this option causes the source
976 information for all enclosing scopes back to the first non-inlined
977 function to be printed as well. For example, if @code{main} inlines
978 @code{callee1} which inlines @code{callee2}, and address is from
979 @code{callee2}, the source information for @code{callee1} and @code{main}
980 will also be printed.
984 @itemx --numeric-sort
985 Sort symbols numerically by their addresses, rather than alphabetically
990 @cindex sorting symbols
991 Do not bother to sort the symbols in any order; print them in the order
996 Use the POSIX.2 standard output format instead of the default format.
997 Equivalent to @samp{-f posix}.
1000 @itemx --reverse-sort
1001 Reverse the order of the sort (whether numeric or alphabetic); let the
1006 Print both value and size of defined symbols for the @code{bsd} output style.
1007 This option has no effect for object formats that do not record symbol
1008 sizes, unless @samp{--size-sort} is also used in which case a
1009 calculated size is displayed.
1012 @itemx --print-armap
1013 @cindex symbol index, listing
1014 When listing symbols from archive members, include the index: a mapping
1015 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1016 contain definitions for which names.
1018 @item -t @var{radix}
1019 @itemx --radix=@var{radix}
1020 Use @var{radix} as the radix for printing the symbol values. It must be
1021 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1024 @itemx --undefined-only
1025 @cindex external symbols
1026 @cindex undefined symbols
1027 Display only undefined symbols (those external to each object file).
1031 Show the version number of @command{nm} and exit.
1034 This option is ignored for compatibility with the AIX version of
1035 @command{nm}. It takes one parameter which must be the string
1036 @option{32_64}. The default mode of AIX @command{nm} corresponds
1037 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1039 @item --defined-only
1040 @cindex external symbols
1041 @cindex undefined symbols
1042 Display only defined symbols for each object file.
1044 @item --plugin @var{name}
1046 Load the plugin called @var{name} to add support for extra target
1047 types. This option is only available if the toolchain has been built
1048 with plugin support enabled.
1050 If @option{--plugin} is not provided, but plugin support has been
1051 enabled then @command{nm} iterates over the files in
1052 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1053 plugin that claims the object in question is used.
1055 Please note that this plugin search directory is @emph{not} the one
1056 used by @command{ld}'s @option{-plugin} option. In order to make
1057 @command{nm} use the linker plugin it must be copied into the
1058 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1059 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1060 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1061 is always backwards compatible with earlier versions, so it is
1062 sufficient to just copy the newest one.
1065 Sort symbols by size. For ELF objects symbol sizes are read from the
1066 ELF, for other object types the symbol sizes are computed as the
1067 difference between the value of the symbol and the value of the symbol
1068 with the next higher value. If the @code{bsd} output format is used
1069 the size of the symbol is printed, rather than the value, and
1070 @samp{-S} must be used in order both size and value to be printed.
1072 @item --special-syms
1073 Display symbols which have a target-specific special meaning. These
1074 symbols are usually used by the target for some special processing and
1075 are not normally helpful when included in the normal symbol lists.
1076 For example for ARM targets this option would skip the mapping symbols
1077 used to mark transitions between ARM code, THUMB code and data.
1080 Include synthetic symbols in the output. These are special symbols
1081 created by the linker for various purposes. They are not shown by
1082 default since they are not part of the binary's original source code.
1084 @item --with-symbol-versions
1085 Enables the display of symbol version information if any exists. The
1086 version string is displayed as a suffix to the symbol name, preceeded by
1087 an @@ character. For example @samp{foo@@VER_1}. If the version is
1088 the default version to be used when resolving unversioned references
1089 to the symbol then it is displayed as a suffix preceeded by two @@
1090 characters. For example @samp{foo@@@@VER_2}.
1092 @item --target=@var{bfdname}
1093 @cindex object code format
1094 Specify an object code format other than your system's default format.
1095 @xref{Target Selection}, for more information.
1102 @c man begin SEEALSO nm
1103 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1110 @c man title objcopy copy and translate object files
1113 @c man begin SYNOPSIS objcopy
1114 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1115 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1116 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1117 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1118 [@option{-S}|@option{--strip-all}]
1119 [@option{-g}|@option{--strip-debug}]
1120 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1121 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1122 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1123 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1124 [@option{--localize-hidden}]
1125 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1126 [@option{--globalize-symbol=}@var{symbolname}]
1127 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1128 [@option{-w}|@option{--wildcard}]
1129 [@option{-x}|@option{--discard-all}]
1130 [@option{-X}|@option{--discard-locals}]
1131 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1132 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1133 [@option{--interleave-width=}@var{width}]
1134 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1135 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1136 [@option{--remove-relocations=}@var{sectionpattern}]
1137 [@option{-p}|@option{--preserve-dates}]
1138 [@option{-D}|@option{--enable-deterministic-archives}]
1139 [@option{-U}|@option{--disable-deterministic-archives}]
1140 [@option{--debugging}]
1141 [@option{--gap-fill=}@var{val}]
1142 [@option{--pad-to=}@var{address}]
1143 [@option{--set-start=}@var{val}]
1144 [@option{--adjust-start=}@var{incr}]
1145 [@option{--change-addresses=}@var{incr}]
1146 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1147 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1148 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1149 [@option{--change-warnings}] [@option{--no-change-warnings}]
1150 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1151 [@option{--add-section} @var{sectionname}=@var{filename}]
1152 [@option{--dump-section} @var{sectionname}=@var{filename}]
1153 [@option{--update-section} @var{sectionname}=@var{filename}]
1154 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1155 [@option{--long-section-names} @{enable,disable,keep@}]
1156 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1157 [@option{--reverse-bytes=}@var{num}]
1158 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1159 [@option{--redefine-sym} @var{old}=@var{new}]
1160 [@option{--redefine-syms=}@var{filename}]
1162 [@option{--keep-symbols=}@var{filename}]
1163 [@option{--strip-symbols=}@var{filename}]
1164 [@option{--strip-unneeded-symbols=}@var{filename}]
1165 [@option{--keep-global-symbols=}@var{filename}]
1166 [@option{--localize-symbols=}@var{filename}]
1167 [@option{--globalize-symbols=}@var{filename}]
1168 [@option{--weaken-symbols=}@var{filename}]
1169 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1170 [@option{--alt-machine-code=}@var{index}]
1171 [@option{--prefix-symbols=}@var{string}]
1172 [@option{--prefix-sections=}@var{string}]
1173 [@option{--prefix-alloc-sections=}@var{string}]
1174 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1175 [@option{--keep-file-symbols}]
1176 [@option{--only-keep-debug}]
1177 [@option{--strip-dwo}]
1178 [@option{--extract-dwo}]
1179 [@option{--extract-symbol}]
1180 [@option{--writable-text}]
1181 [@option{--readonly-text}]
1184 [@option{--file-alignment=}@var{num}]
1185 [@option{--heap=}@var{size}]
1186 [@option{--image-base=}@var{address}]
1187 [@option{--section-alignment=}@var{num}]
1188 [@option{--stack=}@var{size}]
1189 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1190 [@option{--compress-debug-sections}]
1191 [@option{--decompress-debug-sections}]
1192 [@option{--elf-stt-common=@var{val}}]
1193 [@option{--merge-notes}]
1194 [@option{--no-merge-notes}]
1195 [@option{-v}|@option{--verbose}]
1196 [@option{-V}|@option{--version}]
1197 [@option{--help}] [@option{--info}]
1198 @var{infile} [@var{outfile}]
1202 @c man begin DESCRIPTION objcopy
1203 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1204 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1205 read and write the object files. It can write the destination object
1206 file in a format different from that of the source object file. The
1207 exact behavior of @command{objcopy} is controlled by command-line options.
1208 Note that @command{objcopy} should be able to copy a fully linked file
1209 between any two formats. However, copying a relocatable object file
1210 between any two formats may not work as expected.
1212 @command{objcopy} creates temporary files to do its translations and
1213 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1214 translation work; it has access to all the formats described in @sc{bfd}
1215 and thus is able to recognize most formats without being told
1216 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1218 @command{objcopy} can be used to generate S-records by using an output
1219 target of @samp{srec} (e.g., use @samp{-O srec}).
1221 @command{objcopy} can be used to generate a raw binary file by using an
1222 output target of @samp{binary} (e.g., use @option{-O binary}). When
1223 @command{objcopy} generates a raw binary file, it will essentially produce
1224 a memory dump of the contents of the input object file. All symbols and
1225 relocation information will be discarded. The memory dump will start at
1226 the load address of the lowest section copied into the output file.
1228 When generating an S-record or a raw binary file, it may be helpful to
1229 use @option{-S} to remove sections containing debugging information. In
1230 some cases @option{-R} will be useful to remove sections which contain
1231 information that is not needed by the binary file.
1233 Note---@command{objcopy} is not able to change the endianness of its input
1234 files. If the input format has an endianness (some formats do not),
1235 @command{objcopy} can only copy the inputs into file formats that have the
1236 same endianness or which have no endianness (e.g., @samp{srec}).
1237 (However, see the @option{--reverse-bytes} option.)
1241 @c man begin OPTIONS objcopy
1245 @itemx @var{outfile}
1246 The input and output files, respectively.
1247 If you do not specify @var{outfile}, @command{objcopy} creates a
1248 temporary file and destructively renames the result with
1249 the name of @var{infile}.
1251 @item -I @var{bfdname}
1252 @itemx --input-target=@var{bfdname}
1253 Consider the source file's object format to be @var{bfdname}, rather than
1254 attempting to deduce it. @xref{Target Selection}, for more information.
1256 @item -O @var{bfdname}
1257 @itemx --output-target=@var{bfdname}
1258 Write the output file using the object format @var{bfdname}.
1259 @xref{Target Selection}, for more information.
1261 @item -F @var{bfdname}
1262 @itemx --target=@var{bfdname}
1263 Use @var{bfdname} as the object format for both the input and the output
1264 file; i.e., simply transfer data from source to destination with no
1265 translation. @xref{Target Selection}, for more information.
1267 @item -B @var{bfdarch}
1268 @itemx --binary-architecture=@var{bfdarch}
1269 Useful when transforming a architecture-less input file into an object file.
1270 In this case the output architecture can be set to @var{bfdarch}. This
1271 option will be ignored if the input file has a known @var{bfdarch}. You
1272 can access this binary data inside a program by referencing the special
1273 symbols that are created by the conversion process. These symbols are
1274 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1275 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1276 an object file and then access it in your code using these symbols.
1278 @item -j @var{sectionpattern}
1279 @itemx --only-section=@var{sectionpattern}
1280 Copy only the indicated sections from the input file to the output file.
1281 This option may be given more than once. Note that using this option
1282 inappropriately may make the output file unusable. Wildcard
1283 characters are accepted in @var{sectionpattern}.
1285 If the first character of @var{sectionpattern} is the exclamation
1286 point (!) then matching sections will not be copied, even if earlier
1287 use of @option{--only-section} on the same command line would
1288 otherwise copy it. For example:
1291 --only-section=.text.* --only-section=!.text.foo
1294 will copy all sectinos maching '.text.*' but not the section
1297 @item -R @var{sectionpattern}
1298 @itemx --remove-section=@var{sectionpattern}
1299 Remove any section matching @var{sectionpattern} from the output file.
1300 This option may be given more than once. Note that using this option
1301 inappropriately may make the output file unusable. Wildcard
1302 characters are accepted in @var{sectionpattern}. Using both the
1303 @option{-j} and @option{-R} options together results in undefined
1306 If the first character of @var{sectionpattern} is the exclamation
1307 point (!) then matching sections will not be removed even if an
1308 earlier use of @option{--remove-section} on the same command line
1309 would otherwise remove it. For example:
1312 --remove-section=.text.* --remove-section=!.text.foo
1315 will remove all sections matching the pattern '.text.*', but will not
1316 remove the section '.text.foo'.
1318 @item --remove-relocations=@var{sectionpattern}
1319 Remove relocations from the output file for any section matching
1320 @var{sectionpattern}. This option may be given more than once. Note
1321 that using this option inappropriately may make the output file
1322 unusable. Wildcard characters are accepted in @var{sectionpattern}.
1326 --remove-relocations=.text.*
1329 will remove the relocations for all sections matching the patter
1332 If the first character of @var{sectionpattern} is the exclamation
1333 point (!) then matching sections will not have their relocation
1334 removed even if an earlier use of @option{--remove-relocations} on the
1335 same command line would otherwise cause the relocations to be removed.
1339 --remove-relocations=.text.* --remove-relocations=!.text.foo
1342 will remove all relocations for sections matching the pattern
1343 '.text.*', but will not remove relocations for the section
1348 Do not copy relocation and symbol information from the source file.
1351 @itemx --strip-debug
1352 Do not copy debugging symbols or sections from the source file.
1354 @item --strip-unneeded
1355 Strip all symbols that are not needed for relocation processing.
1357 @item -K @var{symbolname}
1358 @itemx --keep-symbol=@var{symbolname}
1359 When stripping symbols, keep symbol @var{symbolname} even if it would
1360 normally be stripped. This option may be given more than once.
1362 @item -N @var{symbolname}
1363 @itemx --strip-symbol=@var{symbolname}
1364 Do not copy symbol @var{symbolname} from the source file. This option
1365 may be given more than once.
1367 @item --strip-unneeded-symbol=@var{symbolname}
1368 Do not copy symbol @var{symbolname} from the source file unless it is needed
1369 by a relocation. This option may be given more than once.
1371 @item -G @var{symbolname}
1372 @itemx --keep-global-symbol=@var{symbolname}
1373 Keep only symbol @var{symbolname} global. Make all other symbols local
1374 to the file, so that they are not visible externally. This option may
1375 be given more than once.
1377 @item --localize-hidden
1378 In an ELF object, mark all symbols that have hidden or internal visibility
1379 as local. This option applies on top of symbol-specific localization options
1380 such as @option{-L}.
1382 @item -L @var{symbolname}
1383 @itemx --localize-symbol=@var{symbolname}
1384 Convert a global or weak symbol called @var{symbolname} into a local
1385 symbol, so that it is not visible externally. This option may be
1386 given more than once. Note - unique symbols are not converted.
1388 @item -W @var{symbolname}
1389 @itemx --weaken-symbol=@var{symbolname}
1390 Make symbol @var{symbolname} weak. This option may be given more than once.
1392 @item --globalize-symbol=@var{symbolname}
1393 Give symbol @var{symbolname} global scoping so that it is visible
1394 outside of the file in which it is defined. This option may be given
1399 Permit regular expressions in @var{symbolname}s used in other command
1400 line options. The question mark (?), asterisk (*), backslash (\) and
1401 square brackets ([]) operators can be used anywhere in the symbol
1402 name. If the first character of the symbol name is the exclamation
1403 point (!) then the sense of the switch is reversed for that symbol.
1410 would cause objcopy to weaken all symbols that start with ``fo''
1411 except for the symbol ``foo''.
1414 @itemx --discard-all
1415 Do not copy non-global symbols from the source file.
1416 @c FIXME any reason to prefer "non-global" to "local" here?
1419 @itemx --discard-locals
1420 Do not copy compiler-generated local symbols.
1421 (These usually start with @samp{L} or @samp{.}.)
1424 @itemx --byte=@var{byte}
1425 If interleaving has been enabled via the @option{--interleave} option
1426 then start the range of bytes to keep at the @var{byte}th byte.
1427 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1428 @var{breadth} is the value given by the @option{--interleave} option.
1430 @item -i [@var{breadth}]
1431 @itemx --interleave[=@var{breadth}]
1432 Only copy a range out of every @var{breadth} bytes. (Header data is
1433 not affected). Select which byte in the range begins the copy with
1434 the @option{--byte} option. Select the width of the range with the
1435 @option{--interleave-width} option.
1437 This option is useful for creating files to program @sc{rom}. It is
1438 typically used with an @code{srec} output target. Note that
1439 @command{objcopy} will complain if you do not specify the
1440 @option{--byte} option as well.
1442 The default interleave breadth is 4, so with @option{--byte} set to 0,
1443 @command{objcopy} would copy the first byte out of every four bytes
1444 from the input to the output.
1446 @item --interleave-width=@var{width}
1447 When used with the @option{--interleave} option, copy @var{width}
1448 bytes at a time. The start of the range of bytes to be copied is set
1449 by the @option{--byte} option, and the extent of the range is set with
1450 the @option{--interleave} option.
1452 The default value for this option is 1. The value of @var{width} plus
1453 the @var{byte} value set by the @option{--byte} option must not exceed
1454 the interleave breadth set by the @option{--interleave} option.
1456 This option can be used to create images for two 16-bit flashes interleaved
1457 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1458 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1459 commands. If the input was '12345678' then the outputs would be
1460 '1256' and '3478' respectively.
1463 @itemx --preserve-dates
1464 Set the access and modification dates of the output file to be the same
1465 as those of the input file.
1468 @itemx --enable-deterministic-archives
1469 @cindex deterministic archives
1470 @kindex --enable-deterministic-archives
1471 Operate in @emph{deterministic} mode. When copying archive members
1472 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1473 and use consistent file modes for all files.
1475 If @file{binutils} was configured with
1476 @option{--enable-deterministic-archives}, then this mode is on by default.
1477 It can be disabled with the @samp{-U} option, below.
1480 @itemx --disable-deterministic-archives
1481 @cindex deterministic archives
1482 @kindex --enable-deterministic-archives
1483 Do @emph{not} operate in @emph{deterministic} mode. This is the
1484 inverse of the @option{-D} option, above: when copying archive members
1485 and writing the archive index, use their actual UID, GID, timestamp,
1486 and file mode values.
1488 This is the default unless @file{binutils} was configured with
1489 @option{--enable-deterministic-archives}.
1492 Convert debugging information, if possible. This is not the default
1493 because only certain debugging formats are supported, and the
1494 conversion process can be time consuming.
1496 @item --gap-fill @var{val}
1497 Fill gaps between sections with @var{val}. This operation applies to
1498 the @emph{load address} (LMA) of the sections. It is done by increasing
1499 the size of the section with the lower address, and filling in the extra
1500 space created with @var{val}.
1502 @item --pad-to @var{address}
1503 Pad the output file up to the load address @var{address}. This is
1504 done by increasing the size of the last section. The extra space is
1505 filled in with the value specified by @option{--gap-fill} (default zero).
1507 @item --set-start @var{val}
1508 Set the start address of the new file to @var{val}. Not all object file
1509 formats support setting the start address.
1511 @item --change-start @var{incr}
1512 @itemx --adjust-start @var{incr}
1513 @cindex changing start address
1514 Change the start address by adding @var{incr}. Not all object file
1515 formats support setting the start address.
1517 @item --change-addresses @var{incr}
1518 @itemx --adjust-vma @var{incr}
1519 @cindex changing object addresses
1520 Change the VMA and LMA addresses of all sections, as well as the start
1521 address, by adding @var{incr}. Some object file formats do not permit
1522 section addresses to be changed arbitrarily. Note that this does not
1523 relocate the sections; if the program expects sections to be loaded at a
1524 certain address, and this option is used to change the sections such
1525 that they are loaded at a different address, the program may fail.
1527 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1528 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1529 @cindex changing section address
1530 Set or change both the VMA address and the LMA address of any section
1531 matching @var{sectionpattern}. If @samp{=} is used, the section
1532 address is set to @var{val}. Otherwise, @var{val} is added to or
1533 subtracted from the section address. See the comments under
1534 @option{--change-addresses}, above. If @var{sectionpattern} does not
1535 match any sections in the input file, a warning will be issued, unless
1536 @option{--no-change-warnings} is used.
1538 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1539 @cindex changing section LMA
1540 Set or change the LMA address of any sections matching
1541 @var{sectionpattern}. The LMA address is the address where the
1542 section will be loaded into memory at program load time. Normally
1543 this is the same as the VMA address, which is the address of the
1544 section at program run time, but on some systems, especially those
1545 where a program is held in ROM, the two can be different. If @samp{=}
1546 is used, the section address is set to @var{val}. Otherwise,
1547 @var{val} is added to or subtracted from the section address. See the
1548 comments under @option{--change-addresses}, above. If
1549 @var{sectionpattern} does not match any sections in the input file, a
1550 warning will be issued, unless @option{--no-change-warnings} is used.
1552 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1553 @cindex changing section VMA
1554 Set or change the VMA address of any section matching
1555 @var{sectionpattern}. The VMA address is the address where the
1556 section will be located once the program has started executing.
1557 Normally this is the same as the LMA address, which is the address
1558 where the section will be loaded into memory, but on some systems,
1559 especially those where a program is held in ROM, the two can be
1560 different. If @samp{=} is used, the section address is set to
1561 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1562 section address. See the comments under @option{--change-addresses},
1563 above. If @var{sectionpattern} does not match any sections in the
1564 input file, a warning will be issued, unless
1565 @option{--no-change-warnings} is used.
1567 @item --change-warnings
1568 @itemx --adjust-warnings
1569 If @option{--change-section-address} or @option{--change-section-lma} or
1570 @option{--change-section-vma} is used, and the section pattern does not
1571 match any sections, issue a warning. This is the default.
1573 @item --no-change-warnings
1574 @itemx --no-adjust-warnings
1575 Do not issue a warning if @option{--change-section-address} or
1576 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1577 if the section pattern does not match any sections.
1579 @item --set-section-flags @var{sectionpattern}=@var{flags}
1580 Set the flags for any sections matching @var{sectionpattern}. The
1581 @var{flags} argument is a comma separated string of flag names. The
1582 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1583 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1584 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1585 for a section which does not have contents, but it is not meaningful
1586 to clear the @samp{contents} flag of a section which does have
1587 contents--just remove the section instead. Not all flags are
1588 meaningful for all object file formats.
1590 @item --add-section @var{sectionname}=@var{filename}
1591 Add a new section named @var{sectionname} while copying the file. The
1592 contents of the new section are taken from the file @var{filename}. The
1593 size of the section will be the size of the file. This option only
1594 works on file formats which can support sections with arbitrary names.
1595 Note - it may be necessary to use the @option{--set-section-flags}
1596 option to set the attributes of the newly created section.
1598 @item --dump-section @var{sectionname}=@var{filename}
1599 Place the contents of section named @var{sectionname} into the file
1600 @var{filename}, overwriting any contents that may have been there
1601 previously. This option is the inverse of @option{--add-section}.
1602 This option is similar to the @option{--only-section} option except
1603 that it does not create a formatted file, it just dumps the contents
1604 as raw binary data, without applying any relocations. The option can
1605 be specified more than once.
1607 @item --update-section @var{sectionname}=@var{filename}
1608 Replace the existing contents of a section named @var{sectionname}
1609 with the contents of file @var{filename}. The size of the section
1610 will be adjusted to the size of the file. The section flags for
1611 @var{sectionname} will be unchanged. For ELF format files the section
1612 to segment mapping will also remain unchanged, something which is not
1613 possible using @option{--remove-section} followed by
1614 @option{--add-section}. The option can be specified more than once.
1616 Note - it is possible to use @option{--rename-section} and
1617 @option{--update-section} to both update and rename a section from one
1618 command line. In this case, pass the original section name to
1619 @option{--update-section}, and the original and new section names to
1620 @option{--rename-section}.
1622 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1623 Add a new symbol named @var{name} while copying the file. This option may be
1624 specified multiple times. If the @var{section} is given, the symbol will be
1625 associated with and relative to that section, otherwise it will be an ABS
1626 symbol. Specifying an undefined section will result in a fatal error. There
1627 is no check for the value, it will be taken as specified. Symbol flags can
1628 be specified and not all flags will be meaningful for all object file
1629 formats. By default, the symbol will be global. The special flag
1630 'before=@var{othersym}' will insert the new symbol in front of the specified
1631 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1632 symbol table in the order they appear.
1634 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1635 Rename a section from @var{oldname} to @var{newname}, optionally
1636 changing the section's flags to @var{flags} in the process. This has
1637 the advantage over usng a linker script to perform the rename in that
1638 the output stays as an object file and does not become a linked
1641 This option is particularly helpful when the input format is binary,
1642 since this will always create a section called .data. If for example,
1643 you wanted instead to create a section called .rodata containing binary
1644 data you could use the following command line to achieve it:
1647 objcopy -I binary -O <output_format> -B <architecture> \
1648 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1649 <input_binary_file> <output_object_file>
1652 @item --long-section-names @{enable,disable,keep@}
1653 Controls the handling of long section names when processing @code{COFF}
1654 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1655 is to preserve long section names if any are present in the input file.
1656 The @samp{enable} and @samp{disable} options forcibly enable or disable
1657 the use of long section names in the output object; when @samp{disable}
1658 is in effect, any long section names in the input object will be truncated.
1659 The @samp{enable} option will only emit long section names if any are
1660 present in the inputs; this is mostly the same as @samp{keep}, but it
1661 is left undefined whether the @samp{enable} option might force the
1662 creation of an empty string table in the output file.
1664 @item --change-leading-char
1665 Some object file formats use special characters at the start of
1666 symbols. The most common such character is underscore, which compilers
1667 often add before every symbol. This option tells @command{objcopy} to
1668 change the leading character of every symbol when it converts between
1669 object file formats. If the object file formats use the same leading
1670 character, this option has no effect. Otherwise, it will add a
1671 character, or remove a character, or change a character, as
1674 @item --remove-leading-char
1675 If the first character of a global symbol is a special symbol leading
1676 character used by the object file format, remove the character. The
1677 most common symbol leading character is underscore. This option will
1678 remove a leading underscore from all global symbols. This can be useful
1679 if you want to link together objects of different file formats with
1680 different conventions for symbol names. This is different from
1681 @option{--change-leading-char} because it always changes the symbol name
1682 when appropriate, regardless of the object file format of the output
1685 @item --reverse-bytes=@var{num}
1686 Reverse the bytes in a section with output contents. A section length must
1687 be evenly divisible by the value given in order for the swap to be able to
1688 take place. Reversing takes place before the interleaving is performed.
1690 This option is used typically in generating ROM images for problematic
1691 target systems. For example, on some target boards, the 32-bit words
1692 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1693 regardless of the CPU byte order. Depending on the programming model, the
1694 endianness of the ROM may need to be modified.
1696 Consider a simple file with a section containing the following eight
1697 bytes: @code{12345678}.
1699 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1700 output file would be ordered @code{21436587}.
1702 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1703 output file would be ordered @code{43218765}.
1705 By using @samp{--reverse-bytes=2} for the above example, followed by
1706 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1707 output file would be ordered @code{34127856}.
1709 @item --srec-len=@var{ival}
1710 Meaningful only for srec output. Set the maximum length of the Srecords
1711 being produced to @var{ival}. This length covers both address, data and
1714 @item --srec-forceS3
1715 Meaningful only for srec output. Avoid generation of S1/S2 records,
1716 creating S3-only record format.
1718 @item --redefine-sym @var{old}=@var{new}
1719 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1720 when one is trying link two things together for which you have no
1721 source, and there are name collisions.
1723 @item --redefine-syms=@var{filename}
1724 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1725 listed in the file @var{filename}. @var{filename} is simply a flat file,
1726 with one symbol pair per line. Line comments may be introduced by the hash
1727 character. This option may be given more than once.
1730 Change all global symbols in the file to be weak. This can be useful
1731 when building an object which will be linked against other objects using
1732 the @option{-R} option to the linker. This option is only effective when
1733 using an object file format which supports weak symbols.
1735 @item --keep-symbols=@var{filename}
1736 Apply @option{--keep-symbol} option to each symbol listed in the file
1737 @var{filename}. @var{filename} is simply a flat file, with one symbol
1738 name per line. Line comments may be introduced by the hash character.
1739 This option may be given more than once.
1741 @item --strip-symbols=@var{filename}
1742 Apply @option{--strip-symbol} option to each symbol listed in the file
1743 @var{filename}. @var{filename} is simply a flat file, with one symbol
1744 name per line. Line comments may be introduced by the hash character.
1745 This option may be given more than once.
1747 @item --strip-unneeded-symbols=@var{filename}
1748 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1749 the file @var{filename}. @var{filename} is simply a flat file, with one
1750 symbol name per line. Line comments may be introduced by the hash
1751 character. This option may be given more than once.
1753 @item --keep-global-symbols=@var{filename}
1754 Apply @option{--keep-global-symbol} option to each symbol listed in the
1755 file @var{filename}. @var{filename} is simply a flat file, with one
1756 symbol name per line. Line comments may be introduced by the hash
1757 character. This option may be given more than once.
1759 @item --localize-symbols=@var{filename}
1760 Apply @option{--localize-symbol} option to each symbol listed in the file
1761 @var{filename}. @var{filename} is simply a flat file, with one symbol
1762 name per line. Line comments may be introduced by the hash character.
1763 This option may be given more than once.
1765 @item --globalize-symbols=@var{filename}
1766 Apply @option{--globalize-symbol} option to each symbol listed in the file
1767 @var{filename}. @var{filename} is simply a flat file, with one symbol
1768 name per line. Line comments may be introduced by the hash character.
1769 This option may be given more than once.
1771 @item --weaken-symbols=@var{filename}
1772 Apply @option{--weaken-symbol} option to each symbol listed in the file
1773 @var{filename}. @var{filename} is simply a flat file, with one symbol
1774 name per line. Line comments may be introduced by the hash character.
1775 This option may be given more than once.
1777 @item --alt-machine-code=@var{index}
1778 If the output architecture has alternate machine codes, use the
1779 @var{index}th code instead of the default one. This is useful in case
1780 a machine is assigned an official code and the tool-chain adopts the
1781 new code, but other applications still depend on the original code
1782 being used. For ELF based architectures if the @var{index}
1783 alternative does not exist then the value is treated as an absolute
1784 number to be stored in the e_machine field of the ELF header.
1786 @item --writable-text
1787 Mark the output text as writable. This option isn't meaningful for all
1788 object file formats.
1790 @item --readonly-text
1791 Make the output text write protected. This option isn't meaningful for all
1792 object file formats.
1795 Mark the output file as demand paged. This option isn't meaningful for all
1796 object file formats.
1799 Mark the output file as impure. This option isn't meaningful for all
1800 object file formats.
1802 @item --prefix-symbols=@var{string}
1803 Prefix all symbols in the output file with @var{string}.
1805 @item --prefix-sections=@var{string}
1806 Prefix all section names in the output file with @var{string}.
1808 @item --prefix-alloc-sections=@var{string}
1809 Prefix all the names of all allocated sections in the output file with
1812 @item --add-gnu-debuglink=@var{path-to-file}
1813 Creates a .gnu_debuglink section which contains a reference to
1814 @var{path-to-file} and adds it to the output file. Note: the file at
1815 @var{path-to-file} must exist. Part of the process of adding the
1816 .gnu_debuglink section involves embedding a checksum of the contents
1817 of the debug info file into the section.
1819 If the debug info file is built in one location but it is going to be
1820 installed at a later time into a different location then do not use
1821 the path to the installed location. The @option{--add-gnu-debuglink}
1822 option will fail because the installed file does not exist yet.
1823 Instead put the debug info file in the current directory and use the
1824 @option{--add-gnu-debuglink} option without any directory components,
1828 objcopy --add-gnu-debuglink=foo.debug
1831 At debug time the debugger will attempt to look for the separate debug
1832 info file in a set of known locations. The exact set of these
1833 locations varies depending upon the distribution being used, but it
1838 @item * The same directory as the executable.
1840 @item * A sub-directory of the directory containing the executable
1843 @item * A global debug directory such as /usr/lib/debug.
1846 As long as the debug info file has been installed into one of these
1847 locations before the debugger is run everything should work
1850 @item --keep-file-symbols
1851 When stripping a file, perhaps with @option{--strip-debug} or
1852 @option{--strip-unneeded}, retain any symbols specifying source file names,
1853 which would otherwise get stripped.
1855 @item --only-keep-debug
1856 Strip a file, removing contents of any sections that would not be
1857 stripped by @option{--strip-debug} and leaving the debugging sections
1858 intact. In ELF files, this preserves all note sections in the output.
1860 Note - the section headers of the stripped sections are preserved,
1861 including their sizes, but the contents of the section are discarded.
1862 The section headers are preserved so that other tools can match up the
1863 debuginfo file with the real executable, even if that executable has
1864 been relocated to a different address space.
1866 The intention is that this option will be used in conjunction with
1867 @option{--add-gnu-debuglink} to create a two part executable. One a
1868 stripped binary which will occupy less space in RAM and in a
1869 distribution and the second a debugging information file which is only
1870 needed if debugging abilities are required. The suggested procedure
1871 to create these files is as follows:
1874 @item Link the executable as normal. Assuming that is is called
1876 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1877 create a file containing the debugging info.
1878 @item Run @code{objcopy --strip-debug foo} to create a
1879 stripped executable.
1880 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1881 to add a link to the debugging info into the stripped executable.
1884 Note---the choice of @code{.dbg} as an extension for the debug info
1885 file is arbitrary. Also the @code{--only-keep-debug} step is
1886 optional. You could instead do this:
1889 @item Link the executable as normal.
1890 @item Copy @code{foo} to @code{foo.full}
1891 @item Run @code{objcopy --strip-debug foo}
1892 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1895 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1896 full executable. It does not have to be a file created by the
1897 @option{--only-keep-debug} switch.
1899 Note---this switch is only intended for use on fully linked files. It
1900 does not make sense to use it on object files where the debugging
1901 information may be incomplete. Besides the gnu_debuglink feature
1902 currently only supports the presence of one filename containing
1903 debugging information, not multiple filenames on a one-per-object-file
1907 Remove the contents of all DWARF .dwo sections, leaving the
1908 remaining debugging sections and all symbols intact.
1909 This option is intended for use by the compiler as part of
1910 the @option{-gsplit-dwarf} option, which splits debug information
1911 between the .o file and a separate .dwo file. The compiler
1912 generates all debug information in the same file, then uses
1913 the @option{--extract-dwo} option to copy the .dwo sections to
1914 the .dwo file, then the @option{--strip-dwo} option to remove
1915 those sections from the original .o file.
1918 Extract the contents of all DWARF .dwo sections. See the
1919 @option{--strip-dwo} option for more information.
1921 @item --file-alignment @var{num}
1922 Specify the file alignment. Sections in the file will always begin at
1923 file offsets which are multiples of this number. This defaults to
1925 [This option is specific to PE targets.]
1927 @item --heap @var{reserve}
1928 @itemx --heap @var{reserve},@var{commit}
1929 Specify the number of bytes of memory to reserve (and optionally commit)
1930 to be used as heap for this program.
1931 [This option is specific to PE targets.]
1933 @item --image-base @var{value}
1934 Use @var{value} as the base address of your program or dll. This is
1935 the lowest memory location that will be used when your program or dll
1936 is loaded. To reduce the need to relocate and improve performance of
1937 your dlls, each should have a unique base address and not overlap any
1938 other dlls. The default is 0x400000 for executables, and 0x10000000
1940 [This option is specific to PE targets.]
1942 @item --section-alignment @var{num}
1943 Sets the section alignment. Sections in memory will always begin at
1944 addresses which are a multiple of this number. Defaults to 0x1000.
1945 [This option is specific to PE targets.]
1947 @item --stack @var{reserve}
1948 @itemx --stack @var{reserve},@var{commit}
1949 Specify the number of bytes of memory to reserve (and optionally commit)
1950 to be used as stack for this program.
1951 [This option is specific to PE targets.]
1953 @item --subsystem @var{which}
1954 @itemx --subsystem @var{which}:@var{major}
1955 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1956 Specifies the subsystem under which your program will execute. The
1957 legal values for @var{which} are @code{native}, @code{windows},
1958 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1959 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1960 the subsystem version also. Numeric values are also accepted for
1962 [This option is specific to PE targets.]
1964 @item --extract-symbol
1965 Keep the file's section flags and symbols but remove all section data.
1966 Specifically, the option:
1969 @item removes the contents of all sections;
1970 @item sets the size of every section to zero; and
1971 @item sets the file's start address to zero.
1974 This option is used to build a @file{.sym} file for a VxWorks kernel.
1975 It can also be a useful way of reducing the size of a @option{--just-symbols}
1978 @item --compress-debug-sections
1979 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
1980 ELF ABI. Note - if compression would actually make a section
1981 @emph{larger}, then it is not compressed.
1983 @item --compress-debug-sections=none
1984 @itemx --compress-debug-sections=zlib
1985 @itemx --compress-debug-sections=zlib-gnu
1986 @itemx --compress-debug-sections=zlib-gabi
1987 For ELF files, these options control how DWARF debug sections are
1988 compressed. @option{--compress-debug-sections=none} is equivalent
1989 to @option{--decompress-debug-sections}.
1990 @option{--compress-debug-sections=zlib} and
1991 @option{--compress-debug-sections=zlib-gabi} are equivalent to
1992 @option{--compress-debug-sections}.
1993 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
1994 sections using zlib. The debug sections are renamed to begin with
1995 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
1996 actually make a section @emph{larger}, then it is not compressed nor
1999 @item --decompress-debug-sections
2000 Decompress DWARF debug sections using zlib. The original section
2001 names of the compressed sections are restored.
2003 @item --elf-stt-common=yes
2004 @itemx --elf-stt-common=no
2005 For ELF files, these options control whether common symbols should be
2006 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2007 @option{--elf-stt-common=yes} converts common symbol type to
2008 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2009 type to @code{STT_OBJECT}.
2012 @itemx --no-merge-notes
2013 For ELF files, attempt (or do not attempt) to reduce the size of any
2014 SHT_NOTE type sections by removing duplicate notes.
2018 Show the version number of @command{objcopy}.
2022 Verbose output: list all object files modified. In the case of
2023 archives, @samp{objcopy -V} lists all members of the archive.
2026 Show a summary of the options to @command{objcopy}.
2029 Display a list showing all architectures and object formats available.
2035 @c man begin SEEALSO objcopy
2036 ld(1), objdump(1), and the Info entries for @file{binutils}.
2043 @cindex object file information
2046 @c man title objdump display information from object files.
2049 @c man begin SYNOPSIS objdump
2050 objdump [@option{-a}|@option{--archive-headers}]
2051 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2052 [@option{-C}|@option{--demangle}[=@var{style}] ]
2053 [@option{-d}|@option{--disassemble}]
2054 [@option{-D}|@option{--disassemble-all}]
2055 [@option{-z}|@option{--disassemble-zeroes}]
2056 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2057 [@option{-f}|@option{--file-headers}]
2058 [@option{-F}|@option{--file-offsets}]
2059 [@option{--file-start-context}]
2060 [@option{-g}|@option{--debugging}]
2061 [@option{-e}|@option{--debugging-tags}]
2062 [@option{-h}|@option{--section-headers}|@option{--headers}]
2063 [@option{-i}|@option{--info}]
2064 [@option{-j} @var{section}|@option{--section=}@var{section}]
2065 [@option{-l}|@option{--line-numbers}]
2066 [@option{-S}|@option{--source}]
2067 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2068 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2069 [@option{-p}|@option{--private-headers}]
2070 [@option{-P} @var{options}|@option{--private=}@var{options}]
2071 [@option{-r}|@option{--reloc}]
2072 [@option{-R}|@option{--dynamic-reloc}]
2073 [@option{-s}|@option{--full-contents}]
2074 [@option{-W[lLiaprmfFsoRt]}|
2075 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames]
2076 [=aranges,=macro,=frames,=frames-interp,=str,=loc]
2077 [=Ranges,=pubtypes,=trace_info,=trace_abbrev]
2078 [=trace_aranges,=gdb_index]
2079 [@option{-G}|@option{--stabs}]
2080 [@option{-t}|@option{--syms}]
2081 [@option{-T}|@option{--dynamic-syms}]
2082 [@option{-x}|@option{--all-headers}]
2083 [@option{-w}|@option{--wide}]
2084 [@option{--start-address=}@var{address}]
2085 [@option{--stop-address=}@var{address}]
2086 [@option{--prefix-addresses}]
2087 [@option{--[no-]show-raw-insn}]
2088 [@option{--adjust-vma=}@var{offset}]
2089 [@option{--dwarf-depth=@var{n}}]
2090 [@option{--dwarf-start=@var{n}}]
2091 [@option{--special-syms}]
2092 [@option{--prefix=}@var{prefix}]
2093 [@option{--prefix-strip=}@var{level}]
2094 [@option{--insn-width=}@var{width}]
2095 [@option{-V}|@option{--version}]
2096 [@option{-H}|@option{--help}]
2097 @var{objfile}@dots{}
2101 @c man begin DESCRIPTION objdump
2103 @command{objdump} displays information about one or more object files.
2104 The options control what particular information to display. This
2105 information is mostly useful to programmers who are working on the
2106 compilation tools, as opposed to programmers who just want their
2107 program to compile and work.
2109 @var{objfile}@dots{} are the object files to be examined. When you
2110 specify archives, @command{objdump} shows information on each of the member
2115 @c man begin OPTIONS objdump
2117 The long and short forms of options, shown here as alternatives, are
2118 equivalent. At least one option from the list
2119 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2123 @itemx --archive-header
2124 @cindex archive headers
2125 If any of the @var{objfile} files are archives, display the archive
2126 header information (in a format similar to @samp{ls -l}). Besides the
2127 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2128 the object file format of each archive member.
2130 @item --adjust-vma=@var{offset}
2131 @cindex section addresses in objdump
2132 @cindex VMA in objdump
2133 When dumping information, first add @var{offset} to all the section
2134 addresses. This is useful if the section addresses do not correspond to
2135 the symbol table, which can happen when putting sections at particular
2136 addresses when using a format which can not represent section addresses,
2139 @item -b @var{bfdname}
2140 @itemx --target=@var{bfdname}
2141 @cindex object code format
2142 Specify that the object-code format for the object files is
2143 @var{bfdname}. This option may not be necessary; @var{objdump} can
2144 automatically recognize many formats.
2148 objdump -b oasys -m vax -h fu.o
2151 displays summary information from the section headers (@option{-h}) of
2152 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2153 file in the format produced by Oasys compilers. You can list the
2154 formats available with the @option{-i} option.
2155 @xref{Target Selection}, for more information.
2158 @itemx --demangle[=@var{style}]
2159 @cindex demangling in objdump
2160 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2161 Besides removing any initial underscore prepended by the system, this
2162 makes C++ function names readable. Different compilers have different
2163 mangling styles. The optional demangling style argument can be used to
2164 choose an appropriate demangling style for your compiler. @xref{c++filt},
2165 for more information on demangling.
2169 Display debugging information. This attempts to parse STABS and IEEE
2170 debugging format information stored in the file and print it out using
2171 a C like syntax. If neither of these formats are found this option
2172 falls back on the @option{-W} option to print any DWARF information in
2176 @itemx --debugging-tags
2177 Like @option{-g}, but the information is generated in a format compatible
2181 @itemx --disassemble
2182 @cindex disassembling object code
2183 @cindex machine instructions
2184 Display the assembler mnemonics for the machine instructions from
2185 @var{objfile}. This option only disassembles those sections which are
2186 expected to contain instructions.
2189 @itemx --disassemble-all
2190 Like @option{-d}, but disassemble the contents of all sections, not just
2191 those expected to contain instructions.
2193 This option also has a subtle effect on the disassembly of
2194 instructions in code sections. When option @option{-d} is in effect
2195 objdump will assume that any symbols present in a code section occur
2196 on the boundary between instructions and it will refuse to disassemble
2197 across such a boundary. When option @option{-D} is in effect however
2198 this assumption is supressed. This means that it is possible for the
2199 output of @option{-d} and @option{-D} to differ if, for example, data
2200 is stored in code sections.
2202 If the target is an ARM architecture this switch also has the effect
2203 of forcing the disassembler to decode pieces of data found in code
2204 sections as if they were instructions.
2206 @item --prefix-addresses
2207 When disassembling, print the complete address on each line. This is
2208 the older disassembly format.
2212 @itemx --endian=@{big|little@}
2214 @cindex disassembly endianness
2215 Specify the endianness of the object files. This only affects
2216 disassembly. This can be useful when disassembling a file format which
2217 does not describe endianness information, such as S-records.
2220 @itemx --file-headers
2221 @cindex object file header
2222 Display summary information from the overall header of
2223 each of the @var{objfile} files.
2226 @itemx --file-offsets
2227 @cindex object file offsets
2228 When disassembling sections, whenever a symbol is displayed, also
2229 display the file offset of the region of data that is about to be
2230 dumped. If zeroes are being skipped, then when disassembly resumes,
2231 tell the user how many zeroes were skipped and the file offset of the
2232 location from where the disassembly resumes. When dumping sections,
2233 display the file offset of the location from where the dump starts.
2235 @item --file-start-context
2236 @cindex source code context
2237 Specify that when displaying interlisted source code/disassembly
2238 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2239 context to the start of the file.
2242 @itemx --section-headers
2244 @cindex section headers
2245 Display summary information from the section headers of the
2248 File segments may be relocated to nonstandard addresses, for example by
2249 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2250 @command{ld}. However, some object file formats, such as a.out, do not
2251 store the starting address of the file segments. In those situations,
2252 although @command{ld} relocates the sections correctly, using @samp{objdump
2253 -h} to list the file section headers cannot show the correct addresses.
2254 Instead, it shows the usual addresses, which are implicit for the
2257 Note, in some cases it is possible for a section to have both the
2258 READONLY and the NOREAD attributes set. In such cases the NOREAD
2259 attribute takes precedence, but @command{objdump} will report both
2260 since the exact setting of the flag bits might be important.
2264 Print a summary of the options to @command{objdump} and exit.
2268 @cindex architectures available
2269 @cindex object formats available
2270 Display a list showing all architectures and object formats available
2271 for specification with @option{-b} or @option{-m}.
2274 @itemx --section=@var{name}
2275 @cindex section information
2276 Display information only for section @var{name}.
2279 @itemx --line-numbers
2280 @cindex source filenames for object files
2281 Label the display (using debugging information) with the filename and
2282 source line numbers corresponding to the object code or relocs shown.
2283 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2285 @item -m @var{machine}
2286 @itemx --architecture=@var{machine}
2287 @cindex architecture
2288 @cindex disassembly architecture
2289 Specify the architecture to use when disassembling object files. This
2290 can be useful when disassembling object files which do not describe
2291 architecture information, such as S-records. You can list the available
2292 architectures with the @option{-i} option.
2294 If the target is an ARM architecture then this switch has an
2295 additional effect. It restricts the disassembly to only those
2296 instructions supported by the architecture specified by @var{machine}.
2297 If it is necessary to use this switch because the input file does not
2298 contain any architecture information, but it is also desired to
2299 disassemble all the instructions use @option{-marm}.
2301 @item -M @var{options}
2302 @itemx --disassembler-options=@var{options}
2303 Pass target specific information to the disassembler. Only supported on
2304 some targets. If it is necessary to specify more than one
2305 disassembler option then multiple @option{-M} options can be used or
2306 can be placed together into a comma separated list.
2308 For ARC, @option{dsp} controls the printing of DSP instructions,
2309 @option{spfp} selects the printing of FPX single precision FP
2310 instructions, @option{dpfp} selects the printing of FPX double
2311 precision FP instructions, @option{quarkse_em} selects the printing of
2312 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2313 of double precision assist instructions, @option{fpus} selects the
2314 printing of FPU single precision FP instructions, while @option{fpud}
2315 selects the printing of FPU souble precision FP instructions.
2317 If the target is an ARM architecture then this switch can be used to
2318 select which register name set is used during disassembler. Specifying
2319 @option{-M reg-names-std} (the default) will select the register names as
2320 used in ARM's instruction set documentation, but with register 13 called
2321 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2322 @option{-M reg-names-apcs} will select the name set used by the ARM
2323 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2324 just use @samp{r} followed by the register number.
2326 There are also two variants on the APCS register naming scheme enabled
2327 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2328 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2329 with the normal register names or the special register names).
2331 This option can also be used for ARM architectures to force the
2332 disassembler to interpret all instructions as Thumb instructions by
2333 using the switch @option{--disassembler-options=force-thumb}. This can be
2334 useful when attempting to disassemble thumb code produced by other
2337 For the x86, some of the options duplicate functions of the @option{-m}
2338 switch, but allow finer grained control. Multiple selections from the
2339 following may be specified as a comma separated string.
2344 Select disassembly for the given architecture.
2348 Select between intel syntax mode and AT&T syntax mode.
2352 Select between AMD64 ISA and Intel64 ISA.
2354 @item intel-mnemonic
2356 Select between intel mnemonic mode and AT&T mnemonic mode.
2357 Note: @code{intel-mnemonic} implies @code{intel} and
2358 @code{att-mnemonic} implies @code{att}.
2365 Specify the default address size and operand size. These four options
2366 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2367 appear later in the option string.
2370 When in AT&T mode, instructs the disassembler to print a mnemonic
2371 suffix even when the suffix could be inferred by the operands.
2374 For PowerPC, the @option{-M} argument @option{raw} selects
2375 disasssembly of hardware insns rather than aliases. For example, you
2376 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2377 rather than @code{li}. All of the @option{-m} arguments for
2378 @command{gas} that select a CPU are supported. These are:
2379 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2380 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2381 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2382 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2383 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2384 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2385 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2386 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2387 @option{power8}, @option{power9}, @option{ppc}, @option{ppc32},
2388 @option{ppc64}, @option{ppc64bridge}, @option{ppcps}, @option{pwr},
2389 @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2390 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2391 @option{pwrx}, @option{titan}, and @option{vle}.
2392 @option{32} and @option{64} modify the default or a prior CPU
2393 selection, disabling and enabling 64-bit insns respectively. In
2394 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2395 and @option{spe} add capabilities to a previous @emph{or later} CPU
2396 selection. @option{any} will disassemble any opcode known to
2397 binutils, but in cases where an opcode has two different meanings or
2398 different arguments, you may not see the disassembly you expect.
2399 If you disassemble without giving a CPU selection, a default will be
2400 chosen from information gleaned by BFD from the object files headers,
2401 but the result again may not be as you expect.
2403 For MIPS, this option controls the printing of instruction mnemonic
2404 names and register names in disassembled instructions. Multiple
2405 selections from the following may be specified as a comma separated
2406 string, and invalid options are ignored:
2410 Print the 'raw' instruction mnemonic instead of some pseudo
2411 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2412 'sll' instead of 'nop', etc.
2415 Disassemble MSA instructions.
2418 Disassemble the virtualization ASE instructions.
2421 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2423 @item gpr-names=@var{ABI}
2424 Print GPR (general-purpose register) names as appropriate
2425 for the specified ABI. By default, GPR names are selected according to
2426 the ABI of the binary being disassembled.
2428 @item fpr-names=@var{ABI}
2429 Print FPR (floating-point register) names as
2430 appropriate for the specified ABI. By default, FPR numbers are printed
2433 @item cp0-names=@var{ARCH}
2434 Print CP0 (system control coprocessor; coprocessor 0) register names
2435 as appropriate for the CPU or architecture specified by
2436 @var{ARCH}. By default, CP0 register names are selected according to
2437 the architecture and CPU of the binary being disassembled.
2439 @item hwr-names=@var{ARCH}
2440 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2441 as appropriate for the CPU or architecture specified by
2442 @var{ARCH}. By default, HWR names are selected according to
2443 the architecture and CPU of the binary being disassembled.
2445 @item reg-names=@var{ABI}
2446 Print GPR and FPR names as appropriate for the selected ABI.
2448 @item reg-names=@var{ARCH}
2449 Print CPU-specific register names (CP0 register and HWR names)
2450 as appropriate for the selected CPU or architecture.
2453 For any of the options listed above, @var{ABI} or
2454 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2455 rather than names, for the selected types of registers.
2456 You can list the available values of @var{ABI} and @var{ARCH} using
2457 the @option{--help} option.
2459 For VAX, you can specify function entry addresses with @option{-M
2460 entry:0xf00ba}. You can use this multiple times to properly
2461 disassemble VAX binary files that don't contain symbol tables (like
2462 ROM dumps). In these cases, the function entry mask would otherwise
2463 be decoded as VAX instructions, which would probably lead the rest
2464 of the function being wrongly disassembled.
2467 @itemx --private-headers
2468 Print information that is specific to the object file format. The exact
2469 information printed depends upon the object file format. For some
2470 object file formats, no additional information is printed.
2472 @item -P @var{options}
2473 @itemx --private=@var{options}
2474 Print information that is specific to the object file format. The
2475 argument @var{options} is a comma separated list that depends on the
2476 format (the lists of options is displayed with the help).
2478 For XCOFF, the available options are:
2494 Not all object formats support this option. In particular the ELF
2495 format does not use it.
2499 @cindex relocation entries, in object file
2500 Print the relocation entries of the file. If used with @option{-d} or
2501 @option{-D}, the relocations are printed interspersed with the
2505 @itemx --dynamic-reloc
2506 @cindex dynamic relocation entries, in object file
2507 Print the dynamic relocation entries of the file. This is only
2508 meaningful for dynamic objects, such as certain types of shared
2509 libraries. As for @option{-r}, if used with @option{-d} or
2510 @option{-D}, the relocations are printed interspersed with the
2514 @itemx --full-contents
2515 @cindex sections, full contents
2516 @cindex object file sections
2517 Display the full contents of any sections requested. By default all
2518 non-empty sections are displayed.
2522 @cindex source disassembly
2523 @cindex disassembly, with source
2524 Display source code intermixed with disassembly, if possible. Implies
2527 @item --prefix=@var{prefix}
2528 @cindex Add prefix to absolute paths
2529 Specify @var{prefix} to add to the absolute paths when used with
2532 @item --prefix-strip=@var{level}
2533 @cindex Strip absolute paths
2534 Indicate how many initial directory names to strip off the hardwired
2535 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2537 @item --show-raw-insn
2538 When disassembling instructions, print the instruction in hex as well as
2539 in symbolic form. This is the default except when
2540 @option{--prefix-addresses} is used.
2542 @item --no-show-raw-insn
2543 When disassembling instructions, do not print the instruction bytes.
2544 This is the default when @option{--prefix-addresses} is used.
2546 @item --insn-width=@var{width}
2547 @cindex Instruction width
2548 Display @var{width} bytes on a single line when disassembling
2551 @item -W[lLiaprmfFsoRt]
2552 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
2553 @itemx --dwarf[=aranges,=macro,=frames,=frames-interp,=str,=loc]
2554 @itemx --dwarf[=Ranges,=pubtypes,=trace_info,=trace_abbrev]
2555 @itemx --dwarf[=trace_aranges,=gdb_index]
2557 @cindex debug symbols
2558 Displays the contents of the debug sections in the file, if any are
2559 present. If one of the optional letters or words follows the switch
2560 then only data found in those specific sections will be dumped.
2562 Note that there is no single letter option to display the content of
2563 trace sections or .gdb_index.
2565 Note: the output from the @option{=info} option can also be affected
2566 by the options @option{--dwarf-depth}, the @option{--dwarf-start} and
2567 the @option{--dwarf-check}.
2569 @item --dwarf-depth=@var{n}
2570 Limit the dump of the @code{.debug_info} section to @var{n} children.
2571 This is only useful with @option{--dwarf=info}. The default is
2572 to print all DIEs; the special value 0 for @var{n} will also have this
2575 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
2576 levels will not be printed. The range for @var{n} is zero-based.
2578 @item --dwarf-start=@var{n}
2579 Print only DIEs beginning with the DIE numbered @var{n}. This is only
2580 useful with @option{--dwarf=info}.
2582 If specified, this option will suppress printing of any header
2583 information and all DIEs before the DIE numbered @var{n}. Only
2584 siblings and children of the specified DIE will be printed.
2586 This can be used in conjunction with @option{--dwarf-depth}.
2589 Enable additional checks for consistency of Dwarf information.
2595 @cindex debug symbols
2596 @cindex ELF object file format
2597 Display the full contents of any sections requested. Display the
2598 contents of the .stab and .stab.index and .stab.excl sections from an
2599 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2600 @code{.stab} debugging symbol-table entries are carried in an ELF
2601 section. In most other file formats, debugging symbol-table entries are
2602 interleaved with linkage symbols, and are visible in the @option{--syms}
2605 @item --start-address=@var{address}
2606 @cindex start-address
2607 Start displaying data at the specified address. This affects the output
2608 of the @option{-d}, @option{-r} and @option{-s} options.
2610 @item --stop-address=@var{address}
2611 @cindex stop-address
2612 Stop displaying data at the specified address. This affects the output
2613 of the @option{-d}, @option{-r} and @option{-s} options.
2617 @cindex symbol table entries, printing
2618 Print the symbol table entries of the file.
2619 This is similar to the information provided by the @samp{nm} program,
2620 although the display format is different. The format of the output
2621 depends upon the format of the file being dumped, but there are two main
2622 types. One looks like this:
2625 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2626 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2629 where the number inside the square brackets is the number of the entry
2630 in the symbol table, the @var{sec} number is the section number, the
2631 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2632 symbol's type, the @var{scl} number is the symbol's storage class and
2633 the @var{nx} value is the number of auxilary entries associated with
2634 the symbol. The last two fields are the symbol's value and its name.
2636 The other common output format, usually seen with ELF based files,
2640 00000000 l d .bss 00000000 .bss
2641 00000000 g .text 00000000 fred
2644 Here the first number is the symbol's value (sometimes refered to as
2645 its address). The next field is actually a set of characters and
2646 spaces indicating the flag bits that are set on the symbol. These
2647 characters are described below. Next is the section with which the
2648 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2649 not connected with any section), or @emph{*UND*} if the section is
2650 referenced in the file being dumped, but not defined there.
2652 After the section name comes another field, a number, which for common
2653 symbols is the alignment and for other symbol is the size. Finally
2654 the symbol's name is displayed.
2656 The flag characters are divided into 7 groups as follows:
2662 The symbol is a local (l), global (g), unique global (u), neither
2663 global nor local (a space) or both global and local (!). A
2664 symbol can be neither local or global for a variety of reasons, e.g.,
2665 because it is used for debugging, but it is probably an indication of
2666 a bug if it is ever both local and global. Unique global symbols are
2667 a GNU extension to the standard set of ELF symbol bindings. For such
2668 a symbol the dynamic linker will make sure that in the entire process
2669 there is just one symbol with this name and type in use.
2672 The symbol is weak (w) or strong (a space).
2675 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2678 The symbol is a warning (W) or a normal symbol (a space). A warning
2679 symbol's name is a message to be displayed if the symbol following the
2680 warning symbol is ever referenced.
2684 The symbol is an indirect reference to another symbol (I), a function
2685 to be evaluated during reloc processing (i) or a normal symbol (a
2690 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2691 normal symbol (a space).
2696 The symbol is the name of a function (F) or a file (f) or an object
2697 (O) or just a normal symbol (a space).
2701 @itemx --dynamic-syms
2702 @cindex dynamic symbol table entries, printing
2703 Print the dynamic symbol table entries of the file. This is only
2704 meaningful for dynamic objects, such as certain types of shared
2705 libraries. This is similar to the information provided by the @samp{nm}
2706 program when given the @option{-D} (@option{--dynamic}) option.
2708 The output format is similar to that produced by the @option{--syms}
2709 option, except that an extra field is inserted before the symbol's
2710 name, giving the version information associated with the symbol.
2711 If the version is the default version to be used when resolving
2712 unversioned references to the symbol then it's displayed as is,
2713 otherwise it's put into parentheses.
2715 @item --special-syms
2716 When displaying symbols include those which the target considers to be
2717 special in some way and which would not normally be of interest to the
2722 Print the version number of @command{objdump} and exit.
2725 @itemx --all-headers
2726 @cindex all header information, object file
2727 @cindex header information, all
2728 Display all available header information, including the symbol table and
2729 relocation entries. Using @option{-x} is equivalent to specifying all of
2730 @option{-a -f -h -p -r -t}.
2734 @cindex wide output, printing
2735 Format some lines for output devices that have more than 80 columns.
2736 Also do not truncate symbol names when they are displayed.
2739 @itemx --disassemble-zeroes
2740 Normally the disassembly output will skip blocks of zeroes. This
2741 option directs the disassembler to disassemble those blocks, just like
2748 @c man begin SEEALSO objdump
2749 nm(1), readelf(1), and the Info entries for @file{binutils}.
2757 @cindex archive contents
2758 @cindex symbol index
2760 @c man title ranlib generate index to archive.
2763 @c man begin SYNOPSIS ranlib
2764 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2768 @c man begin DESCRIPTION ranlib
2770 @command{ranlib} generates an index to the contents of an archive and
2771 stores it in the archive. The index lists each symbol defined by a
2772 member of an archive that is a relocatable object file.
2774 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2776 An archive with such an index speeds up linking to the library and
2777 allows routines in the library to call each other without regard to
2778 their placement in the archive.
2780 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2781 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2786 @c man begin OPTIONS ranlib
2792 Show usage information for @command{ranlib}.
2797 Show the version number of @command{ranlib}.
2800 @cindex deterministic archives
2801 @kindex --enable-deterministic-archives
2802 Operate in @emph{deterministic} mode. The symbol map archive member's
2803 header will show zero for the UID, GID, and timestamp. When this
2804 option is used, multiple runs will produce identical output files.
2806 If @file{binutils} was configured with
2807 @option{--enable-deterministic-archives}, then this mode is on by
2808 default. It can be disabled with the @samp{-U} option, described
2812 Update the timestamp of the symbol map of an archive.
2815 @cindex deterministic archives
2816 @kindex --enable-deterministic-archives
2817 Do @emph{not} operate in @emph{deterministic} mode. This is the
2818 inverse of the @samp{-D} option, above: the archive index will get
2819 actual UID, GID, timestamp, and file mode values.
2821 If @file{binutils} was configured @emph{without}
2822 @option{--enable-deterministic-archives}, then this mode is on by
2830 @c man begin SEEALSO ranlib
2831 ar(1), nm(1), and the Info entries for @file{binutils}.
2839 @cindex section sizes
2841 @c man title size list section sizes and total size.
2844 @c man begin SYNOPSIS size
2845 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2847 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2849 [@option{-t}|@option{--totals}]
2850 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2851 [@var{objfile}@dots{}]
2855 @c man begin DESCRIPTION size
2857 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2858 size---for each of the object or archive files @var{objfile} in its
2859 argument list. By default, one line of output is generated for each
2860 object file or each module in an archive.
2862 @var{objfile}@dots{} are the object files to be examined.
2863 If none are specified, the file @code{a.out} will be used.
2867 @c man begin OPTIONS size
2869 The command line options have the following meanings:
2874 @itemx --format=@var{compatibility}
2875 @cindex @command{size} display format
2876 Using one of these options, you can choose whether the output from @sc{gnu}
2877 @command{size} resembles output from System V @command{size} (using @option{-A},
2878 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2879 @option{--format=berkeley}). The default is the one-line format similar to
2881 @c Bonus for doc-source readers: you can also say --format=strange (or
2882 @c anything else that starts with 's') for sysv, and --format=boring (or
2883 @c anything else that starts with 'b') for Berkeley.
2885 Here is an example of the Berkeley (default) format of output from
2888 $ size --format=Berkeley ranlib size
2889 text data bss dec hex filename
2890 294880 81920 11592 388392 5ed28 ranlib
2891 294880 81920 11888 388688 5ee50 size
2895 This is the same data, but displayed closer to System V conventions:
2898 $ size --format=SysV ranlib size
2916 Show a summary of acceptable arguments and options.
2921 @itemx --radix=@var{number}
2922 @cindex @command{size} number format
2923 @cindex radix for section sizes
2924 Using one of these options, you can control whether the size of each
2925 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2926 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2927 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2928 values (8, 10, 16) are supported. The total size is always given in two
2929 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2930 octal and hexadecimal if you're using @option{-o}.
2933 Print total size of common symbols in each file. When using Berkeley
2934 format these are included in the bss size.
2938 Show totals of all objects listed (Berkeley format listing mode only).
2940 @item --target=@var{bfdname}
2941 @cindex object code format
2942 Specify that the object-code format for @var{objfile} is
2943 @var{bfdname}. This option may not be necessary; @command{size} can
2944 automatically recognize many formats.
2945 @xref{Target Selection}, for more information.
2949 Display the version number of @command{size}.
2955 @c man begin SEEALSO size
2956 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2963 @cindex listings strings
2964 @cindex printing strings
2965 @cindex strings, printing
2967 @c man title strings print the strings of printable characters in files.
2970 @c man begin SYNOPSIS strings
2971 strings [@option{-afovV}] [@option{-}@var{min-len}]
2972 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2973 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2974 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2975 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2976 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2977 [@option{-w}] [@option{--include-all-whitespace}]
2978 [@option{-s}] [@option{--output-separator}@var{sep_string}]
2979 [@option{--help}] [@option{--version}] @var{file}@dots{}
2983 @c man begin DESCRIPTION strings
2985 For each @var{file} given, @sc{gnu} @command{strings} prints the
2986 printable character sequences that are at least 4 characters long (or
2987 the number given with the options below) and are followed by an
2988 unprintable character.
2990 Depending upon how the strings program was configured it will default
2991 to either displaying all the printable sequences that it can find in
2992 each file, or only those sequences that are in loadable, initialized
2993 data sections. If the file type in unrecognizable, or if strings is
2994 reading from stdin then it will always display all of the printable
2995 sequences that it can find.
2997 For backwards compatibility any file that occurs after a command line
2998 option of just @option{-} will also be scanned in full, regardless of
2999 the presence of any @option{-d} option.
3001 @command{strings} is mainly useful for determining the contents of
3006 @c man begin OPTIONS strings
3012 Scan the whole file, regardless of what sections it contains or
3013 whether those sections are loaded or initialized. Normally this is
3014 the default behaviour, but strings can be configured so that the
3015 @option{-d} is the default instead.
3017 The @option{-} option is position dependent and forces strings to
3018 perform full scans of any file that is mentioned after the @option{-}
3019 on the command line, even if the @option{-d} option has been
3024 Only print strings from initialized, loaded data sections in the
3025 file. This may reduce the amount of garbage in the output, but it
3026 also exposes the strings program to any security flaws that may be
3027 present in the BFD library used to scan and load sections. Strings
3028 can be configured so that this option is the default behaviour. In
3029 such cases the @option{-a} option can be used to avoid using the BFD
3030 library and instead just print all of the strings found in the file.
3033 @itemx --print-file-name
3034 Print the name of the file before each string.
3037 Print a summary of the program usage on the standard output and exit.
3039 @item -@var{min-len}
3040 @itemx -n @var{min-len}
3041 @itemx --bytes=@var{min-len}
3042 Print sequences of characters that are at least @var{min-len} characters
3043 long, instead of the default 4.
3046 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3047 act like @samp{-t d} instead. Since we can not be compatible with both
3048 ways, we simply chose one.
3050 @item -t @var{radix}
3051 @itemx --radix=@var{radix}
3052 Print the offset within the file before each string. The single
3053 character argument specifies the radix of the offset---@samp{o} for
3054 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3056 @item -e @var{encoding}
3057 @itemx --encoding=@var{encoding}
3058 Select the character encoding of the strings that are to be found.
3059 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3060 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3061 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3062 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3063 littleendian. Useful for finding wide character strings. (@samp{l}
3064 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3066 @item -T @var{bfdname}
3067 @itemx --target=@var{bfdname}
3068 @cindex object code format
3069 Specify an object code format other than your system's default format.
3070 @xref{Target Selection}, for more information.
3075 Print the program version number on the standard output and exit.
3078 @itemx --include-all-whitespace
3079 By default tab and space characters are included in the strings that
3080 are displayed, but other whitespace characters, such a newlines and
3081 carriage returns, are not. The @option{-w} option changes this so
3082 that all whitespace characters are considered to be part of a string.
3085 @itemx --output-separator
3086 By default, output strings are delimited by a new-line. This option
3087 allows you to supply any string to be used as the output record
3088 separator. Useful with --include-all-whitespace where strings
3089 may contain new-lines internally.
3095 @c man begin SEEALSO strings
3096 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3097 and the Info entries for @file{binutils}.
3105 @cindex removing symbols
3106 @cindex discarding symbols
3107 @cindex symbols, discarding
3109 @c man title strip Discard symbols from object files.
3112 @c man begin SYNOPSIS strip
3113 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3114 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3115 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3116 [@option{-s}|@option{--strip-all}]
3117 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3118 [@option{--strip-dwo}]
3119 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3120 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3121 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3122 [@option{-w}|@option{--wildcard}]
3123 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3124 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3125 [@option{--remove-relocations=}@var{sectionpattern}]
3126 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3127 [@option{-D}|@option{--enable-deterministic-archives}]
3128 [@option{-U}|@option{--disable-deterministic-archives}]
3129 [@option{--keep-file-symbols}]
3130 [@option{--only-keep-debug}]
3131 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3132 [@option{--help}] [@option{--info}]
3133 @var{objfile}@dots{}
3137 @c man begin DESCRIPTION strip
3139 @sc{gnu} @command{strip} discards all symbols from object files
3140 @var{objfile}. The list of object files may include archives.
3141 At least one object file must be given.
3143 @command{strip} modifies the files named in its argument,
3144 rather than writing modified copies under different names.
3148 @c man begin OPTIONS strip
3151 @item -F @var{bfdname}
3152 @itemx --target=@var{bfdname}
3153 Treat the original @var{objfile} as a file with the object
3154 code format @var{bfdname}, and rewrite it in the same format.
3155 @xref{Target Selection}, for more information.
3158 Show a summary of the options to @command{strip} and exit.
3161 Display a list showing all architectures and object formats available.
3163 @item -I @var{bfdname}
3164 @itemx --input-target=@var{bfdname}
3165 Treat the original @var{objfile} as a file with the object
3166 code format @var{bfdname}.
3167 @xref{Target Selection}, for more information.
3169 @item -O @var{bfdname}
3170 @itemx --output-target=@var{bfdname}
3171 Replace @var{objfile} with a file in the output format @var{bfdname}.
3172 @xref{Target Selection}, for more information.
3174 @item -R @var{sectionname}
3175 @itemx --remove-section=@var{sectionname}
3176 Remove any section named @var{sectionname} from the output file, in
3177 addition to whatever sections would otherwise be removed. This
3178 option may be given more than once. Note that using this option
3179 inappropriately may make the output file unusable. The wildcard
3180 character @samp{*} may be given at the end of @var{sectionname}. If
3181 so, then any section starting with @var{sectionname} will be removed.
3183 If the first character of @var{sectionpattern} is the exclamation
3184 point (!) then matching sections will not be removed even if an
3185 earlier use of @option{--remove-section} on the same command line
3186 would otherwise remove it. For example:
3189 --remove-section=.text.* --remove-section=!.text.foo
3192 will remove all sections matching the pattern '.text.*', but will not
3193 remove the section '.text.foo'.
3195 @item --remove-relocations=@var{sectionpattern}
3196 Remove relocations from the output file for any section matching
3197 @var{sectionpattern}. This option may be given more than once. Note
3198 that using this option inappropriately may make the output file
3199 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3203 --remove-relocations=.text.*
3206 will remove the relocations for all sections matching the patter
3209 If the first character of @var{sectionpattern} is the exclamation
3210 point (!) then matching sections will not have their relocation
3211 removed even if an earlier use of @option{--remove-relocations} on the
3212 same command line would otherwise cause the relocations to be removed.
3216 --remove-relocations=.text.* --remove-relocations=!.text.foo
3219 will remove all relocations for sections matching the pattern
3220 '.text.*', but will not remove relocations for the section
3230 @itemx --strip-debug
3231 Remove debugging symbols only.
3234 Remove the contents of all DWARF .dwo sections, leaving the
3235 remaining debugging sections and all symbols intact.
3236 See the description of this option in the @command{objcopy} section
3237 for more information.
3239 @item --strip-unneeded
3240 Remove all symbols that are not needed for relocation processing.
3242 @item -K @var{symbolname}
3243 @itemx --keep-symbol=@var{symbolname}
3244 When stripping symbols, keep symbol @var{symbolname} even if it would
3245 normally be stripped. This option may be given more than once.
3248 @itemx --merge-notes
3249 @itemx --no-merge-notes
3250 For ELF files, attempt (or do not attempt) to reduce the size of any
3251 SHT_NOTE type sections by removing duplicate notes. The default is to
3252 attempt this reduction.
3254 @item -N @var{symbolname}
3255 @itemx --strip-symbol=@var{symbolname}
3256 Remove symbol @var{symbolname} from the source file. This option may be
3257 given more than once, and may be combined with strip options other than
3261 Put the stripped output in @var{file}, rather than replacing the
3262 existing file. When this argument is used, only one @var{objfile}
3263 argument may be specified.
3266 @itemx --preserve-dates
3267 Preserve the access and modification dates of the file.
3270 @itemx --enable-deterministic-archives
3271 @cindex deterministic archives
3272 @kindex --enable-deterministic-archives
3273 Operate in @emph{deterministic} mode. When copying archive members
3274 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3275 and use consistent file modes for all files.
3277 If @file{binutils} was configured with
3278 @option{--enable-deterministic-archives}, then this mode is on by default.
3279 It can be disabled with the @samp{-U} option, below.
3282 @itemx --disable-deterministic-archives
3283 @cindex deterministic archives
3284 @kindex --enable-deterministic-archives
3285 Do @emph{not} operate in @emph{deterministic} mode. This is the
3286 inverse of the @option{-D} option, above: when copying archive members
3287 and writing the archive index, use their actual UID, GID, timestamp,
3288 and file mode values.
3290 This is the default unless @file{binutils} was configured with
3291 @option{--enable-deterministic-archives}.
3295 Permit regular expressions in @var{symbolname}s used in other command
3296 line options. The question mark (?), asterisk (*), backslash (\) and
3297 square brackets ([]) operators can be used anywhere in the symbol
3298 name. If the first character of the symbol name is the exclamation
3299 point (!) then the sense of the switch is reversed for that symbol.
3306 would cause strip to only keep symbols that start with the letters
3307 ``fo'', but to discard the symbol ``foo''.
3310 @itemx --discard-all
3311 Remove non-global symbols.
3314 @itemx --discard-locals
3315 Remove compiler-generated local symbols.
3316 (These usually start with @samp{L} or @samp{.}.)
3318 @item --keep-file-symbols
3319 When stripping a file, perhaps with @option{--strip-debug} or
3320 @option{--strip-unneeded}, retain any symbols specifying source file names,
3321 which would otherwise get stripped.
3323 @item --only-keep-debug
3324 Strip a file, emptying the contents of any sections that would not be
3325 stripped by @option{--strip-debug} and leaving the debugging sections
3326 intact. In ELF files, this preserves all the note sections in the
3329 Note - the section headers of the stripped sections are preserved,
3330 including their sizes, but the contents of the section are discarded.
3331 The section headers are preserved so that other tools can match up the
3332 debuginfo file with the real executable, even if that executable has
3333 been relocated to a different address space.
3335 The intention is that this option will be used in conjunction with
3336 @option{--add-gnu-debuglink} to create a two part executable. One a
3337 stripped binary which will occupy less space in RAM and in a
3338 distribution and the second a debugging information file which is only
3339 needed if debugging abilities are required. The suggested procedure
3340 to create these files is as follows:
3343 @item Link the executable as normal. Assuming that is is called
3345 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3346 create a file containing the debugging info.
3347 @item Run @code{objcopy --strip-debug foo} to create a
3348 stripped executable.
3349 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3350 to add a link to the debugging info into the stripped executable.
3353 Note---the choice of @code{.dbg} as an extension for the debug info
3354 file is arbitrary. Also the @code{--only-keep-debug} step is
3355 optional. You could instead do this:
3358 @item Link the executable as normal.
3359 @item Copy @code{foo} to @code{foo.full}
3360 @item Run @code{strip --strip-debug foo}
3361 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3364 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3365 full executable. It does not have to be a file created by the
3366 @option{--only-keep-debug} switch.
3368 Note---this switch is only intended for use on fully linked files. It
3369 does not make sense to use it on object files where the debugging
3370 information may be incomplete. Besides the gnu_debuglink feature
3371 currently only supports the presence of one filename containing
3372 debugging information, not multiple filenames on a one-per-object-file
3377 Show the version number for @command{strip}.
3381 Verbose output: list all object files modified. In the case of
3382 archives, @samp{strip -v} lists all members of the archive.
3388 @c man begin SEEALSO strip
3389 the Info entries for @file{binutils}.
3393 @node c++filt, addr2line, strip, Top
3397 @cindex demangling C++ symbols
3399 @c man title cxxfilt Demangle C++ and Java symbols.
3402 @c man begin SYNOPSIS cxxfilt
3403 c++filt [@option{-_}|@option{--strip-underscore}]
3404 [@option{-n}|@option{--no-strip-underscore}]
3405 [@option{-p}|@option{--no-params}]
3406 [@option{-t}|@option{--types}]
3407 [@option{-i}|@option{--no-verbose}]
3408 [@option{-s} @var{format}|@option{--format=}@var{format}]
3409 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3413 @c man begin DESCRIPTION cxxfilt
3416 The C++ and Java languages provide function overloading, which means
3417 that you can write many functions with the same name, providing that
3418 each function takes parameters of different types. In order to be
3419 able to distinguish these similarly named functions C++ and Java
3420 encode them into a low-level assembler name which uniquely identifies
3421 each different version. This process is known as @dfn{mangling}. The
3423 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3424 MS-DOS this program is named @command{CXXFILT}.}
3425 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3426 names into user-level names so that they can be read.
3428 Every alphanumeric word (consisting of letters, digits, underscores,
3429 dollars, or periods) seen in the input is a potential mangled name.
3430 If the name decodes into a C++ name, the C++ name replaces the
3431 low-level name in the output, otherwise the original word is output.
3432 In this way you can pass an entire assembler source file, containing
3433 mangled names, through @command{c++filt} and see the same source file
3434 containing demangled names.
3436 You can also use @command{c++filt} to decipher individual symbols by
3437 passing them on the command line:
3440 c++filt @var{symbol}
3443 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3444 names from the standard input instead. All the results are printed on
3445 the standard output. The difference between reading names from the
3446 command line versus reading names from the standard input is that
3447 command line arguments are expected to be just mangled names and no
3448 checking is performed to separate them from surrounding text. Thus
3455 will work and demangle the name to ``f()'' whereas:
3461 will not work. (Note the extra comma at the end of the mangled
3462 name which makes it invalid). This command however will work:
3465 echo _Z1fv, | c++filt -n
3468 and will display ``f(),'', i.e., the demangled name followed by a
3469 trailing comma. This behaviour is because when the names are read
3470 from the standard input it is expected that they might be part of an
3471 assembler source file where there might be extra, extraneous
3472 characters trailing after a mangled name. For example:
3475 .type _Z1fv, @@function
3480 @c man begin OPTIONS cxxfilt
3484 @itemx --strip-underscore
3485 On some systems, both the C and C++ compilers put an underscore in front
3486 of every name. For example, the C name @code{foo} gets the low-level
3487 name @code{_foo}. This option removes the initial underscore. Whether
3488 @command{c++filt} removes the underscore by default is target dependent.
3491 @itemx --no-strip-underscore
3492 Do not remove the initial underscore.
3496 When demangling the name of a function, do not display the types of
3497 the function's parameters.
3501 Attempt to demangle types as well as function names. This is disabled
3502 by default since mangled types are normally only used internally in
3503 the compiler, and they can be confused with non-mangled names. For example,
3504 a function called ``a'' treated as a mangled type name would be
3505 demangled to ``signed char''.
3509 Do not include implementation details (if any) in the demangled
3512 @item -s @var{format}
3513 @itemx --format=@var{format}
3514 @command{c++filt} can decode various methods of mangling, used by
3515 different compilers. The argument to this option selects which
3520 Automatic selection based on executable (the default method)
3522 the one used by the @sc{gnu} C++ compiler (g++)
3524 the one used by the Lucid compiler (lcc)
3526 the one specified by the C++ Annotated Reference Manual
3528 the one used by the HP compiler (aCC)
3530 the one used by the EDG compiler
3532 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3534 the one used by the @sc{gnu} Java compiler (gcj)
3536 the one used by the @sc{gnu} Ada compiler (GNAT).
3540 Print a summary of the options to @command{c++filt} and exit.
3543 Print the version number of @command{c++filt} and exit.
3549 @c man begin SEEALSO cxxfilt
3550 the Info entries for @file{binutils}.
3555 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3556 user interface are subject to change in future releases. In particular,
3557 a command-line option may be required in the future to decode a name
3558 passed as an argument on the command line; in other words,
3561 c++filt @var{symbol}
3565 may in a future release become
3568 c++filt @var{option} @var{symbol}
3576 @cindex address to file name and line number
3578 @c man title addr2line convert addresses into file names and line numbers.
3581 @c man begin SYNOPSIS addr2line
3582 addr2line [@option{-a}|@option{--addresses}]
3583 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3584 [@option{-C}|@option{--demangle}[=@var{style}]]
3585 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3586 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3587 [@option{-i}|@option{--inlines}]
3588 [@option{-p}|@option{--pretty-print}]
3589 [@option{-j}|@option{--section=}@var{name}]
3590 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3595 @c man begin DESCRIPTION addr2line
3597 @command{addr2line} translates addresses into file names and line numbers.
3598 Given an address in an executable or an offset in a section of a relocatable
3599 object, it uses the debugging information to figure out which file name and
3600 line number are associated with it.
3602 The executable or relocatable object to use is specified with the @option{-e}
3603 option. The default is the file @file{a.out}. The section in the relocatable
3604 object to use is specified with the @option{-j} option.
3606 @command{addr2line} has two modes of operation.
3608 In the first, hexadecimal addresses are specified on the command line,
3609 and @command{addr2line} displays the file name and line number for each
3612 In the second, @command{addr2line} reads hexadecimal addresses from
3613 standard input, and prints the file name and line number for each
3614 address on standard output. In this mode, @command{addr2line} may be used
3615 in a pipe to convert dynamically chosen addresses.
3617 The format of the output is @samp{FILENAME:LINENO}. By default
3618 each input address generates one line of output.
3620 Two options can generate additional lines before each
3621 @samp{FILENAME:LINENO} line (in that order).
3623 If the @option{-a} option is used then a line with the input address
3626 If the @option{-f} option is used, then a line with the
3627 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3628 containing the address.
3630 One option can generate additional lines after the
3631 @samp{FILENAME:LINENO} line.
3633 If the @option{-i} option is used and the code at the given address is
3634 present there because of inlining by the compiler then additional
3635 lines are displayed afterwards. One or two extra lines (if the
3636 @option{-f} option is used) are displayed for each inlined function.
3638 Alternatively if the @option{-p} option is used then each input
3639 address generates a single, long, output line containing the address,
3640 the function name, the file name and the line number. If the
3641 @option{-i} option has also been used then any inlined functions will
3642 be displayed in the same manner, but on separate lines, and prefixed
3643 by the text @samp{(inlined by)}.
3645 If the file name or function name can not be determined,
3646 @command{addr2line} will print two question marks in their place. If the
3647 line number can not be determined, @command{addr2line} will print 0.
3651 @c man begin OPTIONS addr2line
3653 The long and short forms of options, shown here as alternatives, are
3659 Display the address before the function name, file and line number
3660 information. The address is printed with a @samp{0x} prefix to easily
3663 @item -b @var{bfdname}
3664 @itemx --target=@var{bfdname}
3665 @cindex object code format
3666 Specify that the object-code format for the object files is
3670 @itemx --demangle[=@var{style}]
3671 @cindex demangling in objdump
3672 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3673 Besides removing any initial underscore prepended by the system, this
3674 makes C++ function names readable. Different compilers have different
3675 mangling styles. The optional demangling style argument can be used to
3676 choose an appropriate demangling style for your compiler. @xref{c++filt},
3677 for more information on demangling.
3679 @item -e @var{filename}
3680 @itemx --exe=@var{filename}
3681 Specify the name of the executable for which addresses should be
3682 translated. The default file is @file{a.out}.
3686 Display function names as well as file and line number information.
3690 Display only the base of each file name.
3694 If the address belongs to a function that was inlined, the source
3695 information for all enclosing scopes back to the first non-inlined
3696 function will also be printed. For example, if @code{main} inlines
3697 @code{callee1} which inlines @code{callee2}, and address is from
3698 @code{callee2}, the source information for @code{callee1} and @code{main}
3699 will also be printed.
3703 Read offsets relative to the specified section instead of absolute addresses.
3706 @itemx --pretty-print
3707 Make the output more human friendly: each location are printed on one line.
3708 If option @option{-i} is specified, lines for all enclosing scopes are
3709 prefixed with @samp{(inlined by)}.
3715 @c man begin SEEALSO addr2line
3716 Info entries for @file{binutils}.
3723 @command{nlmconv} converts a relocatable object file into a NetWare
3727 @command{nlmconv} currently works with @samp{i386} object
3728 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
3729 object files in @sc{elf}, or @code{a.out} format@footnote{
3730 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
3731 format in the Binary File Descriptor library. It has only been tested
3732 with the above formats.}.
3736 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
3737 utilities, since it is only useful for NLM targets.
3740 @c man title nlmconv converts object code into an NLM.
3743 @c man begin SYNOPSIS nlmconv
3744 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
3745 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
3746 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
3747 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
3748 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3749 @var{infile} @var{outfile}
3753 @c man begin DESCRIPTION nlmconv
3755 @command{nlmconv} converts the relocatable @samp{i386} object file
3756 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
3757 reading @var{headerfile} for NLM header information. For instructions
3758 on writing the NLM command file language used in header files, see the
3759 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
3760 Development and Tools Overview}, which is part of the NLM Software
3761 Developer's Kit (``NLM SDK''), available from Novell, Inc.
3762 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
3765 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
3768 @command{nlmconv} can perform a link step. In other words, you can list
3769 more than one object file for input if you list them in the definitions
3770 file (rather than simply specifying one input file on the command line).
3771 In this case, @command{nlmconv} calls the linker for you.
3775 @c man begin OPTIONS nlmconv
3778 @item -I @var{bfdname}
3779 @itemx --input-target=@var{bfdname}
3780 Object format of the input file. @command{nlmconv} can usually determine
3781 the format of a given file (so no default is necessary).
3782 @xref{Target Selection}, for more information.
3784 @item -O @var{bfdname}
3785 @itemx --output-target=@var{bfdname}
3786 Object format of the output file. @command{nlmconv} infers the output
3787 format based on the input format, e.g. for a @samp{i386} input file the
3788 output format is @samp{nlm32-i386}.
3789 @xref{Target Selection}, for more information.
3791 @item -T @var{headerfile}
3792 @itemx --header-file=@var{headerfile}
3793 Reads @var{headerfile} for NLM header information. For instructions on
3794 writing the NLM command file language used in header files, see@ see the
3795 @samp{linkers} section, of the @cite{NLM Development and Tools
3796 Overview}, which is part of the NLM Software Developer's Kit, available
3801 Displays (on standard error) the linker command line used by @command{nlmconv}.
3803 @item -l @var{linker}
3804 @itemx --linker=@var{linker}
3805 Use @var{linker} for any linking. @var{linker} can be an absolute or a
3810 Prints a usage summary.
3814 Prints the version number for @command{nlmconv}.
3820 @c man begin SEEALSO nlmconv
3821 the Info entries for @file{binutils}.
3828 @command{windmc} may be used to generator Windows message resources.
3831 @emph{Warning:} @command{windmc} is not always built as part of the binary
3832 utilities, since it is only useful for Windows targets.
3835 @c man title windmc generates Windows message resources.
3838 @c man begin SYNOPSIS windmc
3839 windmc [options] input-file
3843 @c man begin DESCRIPTION windmc
3845 @command{windmc} reads message definitions from an input file (.mc) and
3846 translate them into a set of output files. The output files may be of
3851 A C header file containing the message definitions.
3854 A resource file compilable by the @command{windres} tool.
3857 One or more binary files containing the resource data for a specific
3861 A C include file that maps message id's to their symbolic name.
3864 The exact description of these different formats is available in
3865 documentation from Microsoft.
3867 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3868 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3869 Windows Message Compiler.
3873 @c man begin OPTIONS windmc
3878 Specifies that the input file specified is ASCII. This is the default
3883 Specifies that messages in the output @code{bin} files should be in ASCII
3888 Specifies that @code{bin} filenames should have to be prefixed by the
3889 basename of the source file.
3893 Sets the customer bit in all message id's.
3895 @item -C @var{codepage}
3896 @itemx --codepage_in @var{codepage}
3897 Sets the default codepage to be used to convert input file to UTF16. The
3898 default is ocdepage 1252.
3901 @itemx --decimal_values
3902 Outputs the constants in the header file in decimal. Default is using
3906 @itemx --extension @var{ext}
3907 The extension for the header file. The default is .h extension.
3909 @item -F @var{target}
3910 @itemx --target @var{target}
3911 Specify the BFD format to use for a bin file as output. This
3912 is a BFD target name; you can use the @option{--help} option to see a list
3913 of supported targets. Normally @command{windmc} will use the default
3914 format, which is the first one listed by the @option{--help} option.
3916 @ref{Target Selection}.
3920 @itemx --headerdir @var{path}
3921 The target directory of the generated header file. The default is the
3926 Displays a list of command line options and then exits.
3928 @item -m @var{characters}
3929 @itemx --maxlength @var{characters}
3930 Instructs @command{windmc} to generate a warning if the length
3931 of any message exceeds the number specified.
3934 @itemx --nullterminate
3935 Terminate message text in @code{bin} files by zero. By default they are
3936 terminated by CR/LF.
3939 @itemx --hresult_use
3940 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3941 file, using HRESULT definitions. Status codes are used if the flag is not
3944 @item -O @var{codepage}
3945 @itemx --codepage_out @var{codepage}
3946 Sets the default codepage to be used to output text files. The default
3950 @itemx --rcdir @var{path}
3951 The target directory for the generated @code{rc} script and the generated
3952 @code{bin} files that the resource compiler script includes. The default
3953 is the current directory.
3957 Specifies that the input file is UTF16.
3960 @itemx --unicode_out
3961 Specifies that messages in the output @code{bin} file should be in UTF16
3962 format. This is the default behaviour.
3966 Enable verbose mode.
3970 Prints the version number for @command{windmc}.
3973 @itemx --xdgb @var{path}
3974 The path of the @code{dbg} C include file that maps message id's to the
3975 symbolic name. No such file is generated without specifying the switch.
3981 @c man begin SEEALSO windmc
3982 the Info entries for @file{binutils}.
3989 @command{windres} may be used to manipulate Windows resources.
3992 @emph{Warning:} @command{windres} is not always built as part of the binary
3993 utilities, since it is only useful for Windows targets.
3996 @c man title windres manipulate Windows resources.
3999 @c man begin SYNOPSIS windres
4000 windres [options] [input-file] [output-file]
4004 @c man begin DESCRIPTION windres
4006 @command{windres} reads resources from an input file and copies them into
4007 an output file. Either file may be in one of three formats:
4011 A text format read by the Resource Compiler.
4014 A binary format generated by the Resource Compiler.
4017 A COFF object or executable.
4020 The exact description of these different formats is available in
4021 documentation from Microsoft.
4023 When @command{windres} converts from the @code{rc} format to the @code{res}
4024 format, it is acting like the Windows Resource Compiler. When
4025 @command{windres} converts from the @code{res} format to the @code{coff}
4026 format, it is acting like the Windows @code{CVTRES} program.
4028 When @command{windres} generates an @code{rc} file, the output is similar
4029 but not identical to the format expected for the input. When an input
4030 @code{rc} file refers to an external filename, an output @code{rc} file
4031 will instead include the file contents.
4033 If the input or output format is not specified, @command{windres} will
4034 guess based on the file name, or, for the input file, the file contents.
4035 A file with an extension of @file{.rc} will be treated as an @code{rc}
4036 file, a file with an extension of @file{.res} will be treated as a
4037 @code{res} file, and a file with an extension of @file{.o} or
4038 @file{.exe} will be treated as a @code{coff} file.
4040 If no output file is specified, @command{windres} will print the resources
4041 in @code{rc} format to standard output.
4043 The normal use is for you to write an @code{rc} file, use @command{windres}
4044 to convert it to a COFF object file, and then link the COFF file into
4045 your application. This will make the resources described in the
4046 @code{rc} file available to Windows.
4050 @c man begin OPTIONS windres
4053 @item -i @var{filename}
4054 @itemx --input @var{filename}
4055 The name of the input file. If this option is not used, then
4056 @command{windres} will use the first non-option argument as the input file
4057 name. If there are no non-option arguments, then @command{windres} will
4058 read from standard input. @command{windres} can not read a COFF file from
4061 @item -o @var{filename}
4062 @itemx --output @var{filename}
4063 The name of the output file. If this option is not used, then
4064 @command{windres} will use the first non-option argument, after any used
4065 for the input file name, as the output file name. If there is no
4066 non-option argument, then @command{windres} will write to standard output.
4067 @command{windres} can not write a COFF file to standard output. Note,
4068 for compatibility with @command{rc} the option @option{-fo} is also
4069 accepted, but its use is not recommended.
4071 @item -J @var{format}
4072 @itemx --input-format @var{format}
4073 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4074 @samp{coff}. If no input format is specified, @command{windres} will
4075 guess, as described above.
4077 @item -O @var{format}
4078 @itemx --output-format @var{format}
4079 The output format to generate. @var{format} may be @samp{res},
4080 @samp{rc}, or @samp{coff}. If no output format is specified,
4081 @command{windres} will guess, as described above.
4083 @item -F @var{target}
4084 @itemx --target @var{target}
4085 Specify the BFD format to use for a COFF file as input or output. This
4086 is a BFD target name; you can use the @option{--help} option to see a list
4087 of supported targets. Normally @command{windres} will use the default
4088 format, which is the first one listed by the @option{--help} option.
4090 @ref{Target Selection}.
4093 @item --preprocessor @var{program}
4094 When @command{windres} reads an @code{rc} file, it runs it through the C
4095 preprocessor first. This option may be used to specify the preprocessor
4096 to use, including any leading arguments. The default preprocessor
4097 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
4099 @item --preprocessor-arg @var{option}
4100 When @command{windres} reads an @code{rc} file, it runs it through
4101 the C preprocessor first. This option may be used to specify additional
4102 text to be passed to preprocessor on its command line.
4103 This option can be used multiple times to add multiple options to the
4104 preprocessor command line.
4106 @item -I @var{directory}
4107 @itemx --include-dir @var{directory}
4108 Specify an include directory to use when reading an @code{rc} file.
4109 @command{windres} will pass this to the preprocessor as an @option{-I}
4110 option. @command{windres} will also search this directory when looking for
4111 files named in the @code{rc} file. If the argument passed to this command
4112 matches any of the supported @var{formats} (as described in the @option{-J}
4113 option), it will issue a deprecation warning, and behave just like the
4114 @option{-J} option. New programs should not use this behaviour. If a
4115 directory happens to match a @var{format}, simple prefix it with @samp{./}
4116 to disable the backward compatibility.
4118 @item -D @var{target}
4119 @itemx --define @var{sym}[=@var{val}]
4120 Specify a @option{-D} option to pass to the preprocessor when reading an
4123 @item -U @var{target}
4124 @itemx --undefine @var{sym}
4125 Specify a @option{-U} option to pass to the preprocessor when reading an
4129 Ignored for compatibility with rc.
4132 Enable verbose mode. This tells you what the preprocessor is if you
4136 @item --codepage @var{val}
4137 Specify the default codepage to use when reading an @code{rc} file.
4138 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4139 codepage code. The valid range is from zero up to 0xffff, but the
4140 validity of the codepage is host and configuration dependent.
4143 @item --language @var{val}
4144 Specify the default language to use when reading an @code{rc} file.
4145 @var{val} should be a hexadecimal language code. The low eight bits are
4146 the language, and the high eight bits are the sublanguage.
4148 @item --use-temp-file
4149 Use a temporary file to instead of using popen to read the output of
4150 the preprocessor. Use this option if the popen implementation is buggy
4151 on the host (eg., certain non-English language versions of Windows 95 and
4152 Windows 98 are known to have buggy popen where the output will instead
4155 @item --no-use-temp-file
4156 Use popen, not a temporary file, to read the output of the preprocessor.
4157 This is the default behaviour.
4161 Prints a usage summary.
4165 Prints the version number for @command{windres}.
4168 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4169 this will turn on parser debugging.
4175 @c man begin SEEALSO windres
4176 the Info entries for @file{binutils}.
4185 @command{dlltool} is used to create the files needed to create dynamic
4186 link libraries (DLLs) on systems which understand PE format image
4187 files such as Windows. A DLL contains an export table which contains
4188 information that the runtime loader needs to resolve references from a
4189 referencing program.
4191 The export table is generated by this program by reading in a
4192 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4193 will be in the DLL. A @file{.o} file can contain information in
4194 special @samp{.drectve} sections with export information.
4197 @emph{Note:} @command{dlltool} is not always built as part of the
4198 binary utilities, since it is only useful for those targets which
4202 @c man title dlltool Create files needed to build and use DLLs.
4205 @c man begin SYNOPSIS dlltool
4206 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4207 [@option{-b}|@option{--base-file} @var{base-file-name}]
4208 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4209 [@option{-z}|@option{--output-def} @var{def-file-name}]
4210 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4211 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4212 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4213 [@option{--exclude-symbols} @var{list}]
4214 [@option{--no-default-excludes}]
4215 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4216 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4217 [@option{-a}|@option{--add-indirect}]
4218 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4219 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4220 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4221 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4222 [@option{--use-nul-prefixed-import-tables}]
4223 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4224 [@option{-i}|@option{--interwork}]
4225 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4226 [@option{-v}|@option{--verbose}]
4227 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4228 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4229 [object-file @dots{}]
4233 @c man begin DESCRIPTION dlltool
4235 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4236 @option{-b} options as well as object files specified on the command
4237 line. It then processes these inputs and if the @option{-e} option has
4238 been specified it creates a exports file. If the @option{-l} option
4239 has been specified it creates a library file and if the @option{-z} option
4240 has been specified it creates a def file. Any or all of the @option{-e},
4241 @option{-l} and @option{-z} options can be present in one invocation of
4244 When creating a DLL, along with the source for the DLL, it is necessary
4245 to have three other files. @command{dlltool} can help with the creation of
4248 The first file is a @file{.def} file which specifies which functions are
4249 exported from the DLL, which functions the DLL imports, and so on. This
4250 is a text file and can be created by hand, or @command{dlltool} can be used
4251 to create it using the @option{-z} option. In this case @command{dlltool}
4252 will scan the object files specified on its command line looking for
4253 those functions which have been specially marked as being exported and
4254 put entries for them in the @file{.def} file it creates.
4256 In order to mark a function as being exported from a DLL, it needs to
4257 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4258 section of the object file. This can be done in C by using the
4262 asm (".section .drectve");
4263 asm (".ascii \"-export:my_func\"");
4265 int my_func (void) @{ @dots{} @}
4268 The second file needed for DLL creation is an exports file. This file
4269 is linked with the object files that make up the body of the DLL and it
4270 handles the interface between the DLL and the outside world. This is a
4271 binary file and it can be created by giving the @option{-e} option to
4272 @command{dlltool} when it is creating or reading in a @file{.def} file.
4274 The third file needed for DLL creation is the library file that programs
4275 will link with in order to access the functions in the DLL (an `import
4276 library'). This file can be created by giving the @option{-l} option to
4277 dlltool when it is creating or reading in a @file{.def} file.
4279 If the @option{-y} option is specified, dlltool generates a delay-import
4280 library that can be used instead of the normal import library to allow
4281 a program to link to the dll only as soon as an imported function is
4282 called for the first time. The resulting executable will need to be
4283 linked to the static delayimp library containing __delayLoadHelper2(),
4284 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4286 @command{dlltool} builds the library file by hand, but it builds the
4287 exports file by creating temporary files containing assembler statements
4288 and then assembling these. The @option{-S} command line option can be
4289 used to specify the path to the assembler that dlltool will use,
4290 and the @option{-f} option can be used to pass specific flags to that
4291 assembler. The @option{-n} can be used to prevent dlltool from deleting
4292 these temporary assembler files when it is done, and if @option{-n} is
4293 specified twice then this will prevent dlltool from deleting the
4294 temporary object files it used to build the library.
4296 Here is an example of creating a DLL from a source file @samp{dll.c} and
4297 also creating a program (from an object file called @samp{program.o})
4302 dlltool -e exports.o -l dll.lib dll.o
4303 gcc dll.o exports.o -o dll.dll
4304 gcc program.o dll.lib -o program
4308 @command{dlltool} may also be used to query an existing import library
4309 to determine the name of the DLL to which it is associated. See the
4310 description of the @option{-I} or @option{--identify} option.
4314 @c man begin OPTIONS dlltool
4316 The command line options have the following meanings:
4320 @item -d @var{filename}
4321 @itemx --input-def @var{filename}
4322 @cindex input .def file
4323 Specifies the name of a @file{.def} file to be read in and processed.
4325 @item -b @var{filename}
4326 @itemx --base-file @var{filename}
4328 Specifies the name of a base file to be read in and processed. The
4329 contents of this file will be added to the relocation section in the
4330 exports file generated by dlltool.
4332 @item -e @var{filename}
4333 @itemx --output-exp @var{filename}
4334 Specifies the name of the export file to be created by dlltool.
4336 @item -z @var{filename}
4337 @itemx --output-def @var{filename}
4338 Specifies the name of the @file{.def} file to be created by dlltool.
4340 @item -l @var{filename}
4341 @itemx --output-lib @var{filename}
4342 Specifies the name of the library file to be created by dlltool.
4344 @item -y @var{filename}
4345 @itemx --output-delaylib @var{filename}
4346 Specifies the name of the delay-import library file to be created by dlltool.
4348 @item --export-all-symbols
4349 Treat all global and weak defined symbols found in the input object
4350 files as symbols to be exported. There is a small list of symbols which
4351 are not exported by default; see the @option{--no-default-excludes}
4352 option. You may add to the list of symbols to not export by using the
4353 @option{--exclude-symbols} option.
4355 @item --no-export-all-symbols
4356 Only export symbols explicitly listed in an input @file{.def} file or in
4357 @samp{.drectve} sections in the input object files. This is the default
4358 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4359 attributes in the source code.
4361 @item --exclude-symbols @var{list}
4362 Do not export the symbols in @var{list}. This is a list of symbol names
4363 separated by comma or colon characters. The symbol names should not
4364 contain a leading underscore. This is only meaningful when
4365 @option{--export-all-symbols} is used.
4367 @item --no-default-excludes
4368 When @option{--export-all-symbols} is used, it will by default avoid
4369 exporting certain special symbols. The current list of symbols to avoid
4370 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4371 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4372 to go ahead and export these special symbols. This is only meaningful
4373 when @option{--export-all-symbols} is used.
4376 @itemx --as @var{path}
4377 Specifies the path, including the filename, of the assembler to be used
4378 to create the exports file.
4380 @item -f @var{options}
4381 @itemx --as-flags @var{options}
4382 Specifies any specific command line options to be passed to the
4383 assembler when building the exports file. This option will work even if
4384 the @option{-S} option is not used. This option only takes one argument,
4385 and if it occurs more than once on the command line, then later
4386 occurrences will override earlier occurrences. So if it is necessary to
4387 pass multiple options to the assembler they should be enclosed in
4391 @itemx --dll-name @var{name}
4392 Specifies the name to be stored in the @file{.def} file as the name of
4393 the DLL when the @option{-e} option is used. If this option is not
4394 present, then the filename given to the @option{-e} option will be
4395 used as the name of the DLL.
4397 @item -m @var{machine}
4398 @itemx -machine @var{machine}
4399 Specifies the type of machine for which the library file should be
4400 built. @command{dlltool} has a built in default type, depending upon how
4401 it was created, but this option can be used to override that. This is
4402 normally only useful when creating DLLs for an ARM processor, when the
4403 contents of the DLL are actually encode using Thumb instructions.
4406 @itemx --add-indirect
4407 Specifies that when @command{dlltool} is creating the exports file it
4408 should add a section which allows the exported functions to be
4409 referenced without using the import library. Whatever the hell that
4413 @itemx --add-underscore
4414 Specifies that when @command{dlltool} is creating the exports file it
4415 should prepend an underscore to the names of @emph{all} exported symbols.
4417 @item --no-leading-underscore
4418 @item --leading-underscore
4419 Specifies whether standard symbol should be forced to be prefixed, or
4422 @item --add-stdcall-underscore
4423 Specifies that when @command{dlltool} is creating the exports file it
4424 should prepend an underscore to the names of exported @emph{stdcall}
4425 functions. Variable names and non-stdcall function names are not modified.
4426 This option is useful when creating GNU-compatible import libs for third
4427 party DLLs that were built with MS-Windows tools.
4431 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4432 of stdcall functions that will be imported from the DLL. This is
4433 useful when creating an import library for a DLL which exports stdcall
4434 functions but without the usual @samp{@@<number>} symbol name suffix.
4436 This does not change the naming of symbols provided by the import library
4437 to programs linked against it, but only the entries in the import table
4438 (ie the .idata section).
4441 @itemx --add-stdcall-alias
4442 Specifies that when @command{dlltool} is creating the exports file it
4443 should add aliases for stdcall symbols without @samp{@@ <number>}
4444 in addition to the symbols with @samp{@@ <number>}.
4447 @itemx --ext-prefix-alias @var{prefix}
4448 Causes @command{dlltool} to create external aliases for all DLL
4449 imports with the specified prefix. The aliases are created for both
4450 external and import symbols with no leading underscore.
4454 Specifies that when @command{dlltool} is creating the exports and library
4455 files it should omit the @code{.idata4} section. This is for compatibility
4456 with certain operating systems.
4458 @item --use-nul-prefixed-import-tables
4459 Specifies that when @command{dlltool} is creating the exports and library
4460 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4461 element. This emulates old gnu import library generation of
4462 @code{dlltool}. By default this option is turned off.
4466 Specifies that when @command{dlltool} is creating the exports and library
4467 files it should omit the @code{.idata5} section. This is for compatibility
4468 with certain operating systems.
4470 @item -I @var{filename}
4471 @itemx --identify @var{filename}
4472 Specifies that @command{dlltool} should inspect the import library
4473 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4474 of the associated DLL(s). This can be performed in addition to any
4475 other operations indicated by the other options and arguments.
4476 @command{dlltool} fails if the import library does not exist or is not
4477 actually an import library. See also @option{--identify-strict}.
4479 @item --identify-strict
4480 Modifies the behavior of the @option{--identify} option, such
4481 that an error is reported if @var{filename} is associated with
4486 Specifies that @command{dlltool} should mark the objects in the library
4487 file and exports file that it produces as supporting interworking
4488 between ARM and Thumb code.
4492 Makes @command{dlltool} preserve the temporary assembler files it used to
4493 create the exports file. If this option is repeated then dlltool will
4494 also preserve the temporary object files it uses to create the library
4497 @item -t @var{prefix}
4498 @itemx --temp-prefix @var{prefix}
4499 Makes @command{dlltool} use @var{prefix} when constructing the names of
4500 temporary assembler and object files. By default, the temp file prefix
4501 is generated from the pid.
4505 Make dlltool describe what it is doing.
4509 Displays a list of command line options and then exits.
4513 Displays dlltool's version number and then exits.
4520 * def file format:: The format of the dlltool @file{.def} file
4523 @node def file format
4524 @section The format of the @command{dlltool} @file{.def} file
4526 A @file{.def} file contains any number of the following commands:
4530 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4531 The result is going to be named @var{name}@code{.exe}.
4533 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4534 The result is going to be named @var{name}@code{.dll}.
4535 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4536 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4539 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4540 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4541 Declares @var{name1} as an exported symbol from the DLL, with optional
4542 ordinal number @var{integer}, or declares @var{name1} as an alias
4543 (forward) of the function @var{external-name} in the DLL.
4544 If @var{its_name} is specified, this name is used as string in export table.
4546 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4547 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4548 If you want to use LIBRARY as name then you need to quote it.
4550 @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{]} *}
4551 Declares that @var{external-name} or the exported function whose
4552 ordinal number is @var{integer} is to be imported from the file
4553 @var{module-name}. If @var{internal-name} is specified then this is
4554 the name that the imported function will be referred to in the body of
4556 If @var{its_name} is specified, this name is used as string in import table.
4557 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4558 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4559 If you want to use LIBRARY as name then you need to quote it.
4561 @item @code{DESCRIPTION} @var{string}
4562 Puts @var{string} into the output @file{.exp} file in the
4563 @code{.rdata} section.
4565 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4566 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4567 Generates @code{--stack} or @code{--heap}
4568 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4569 section. The linker will see this and act upon it.
4571 @item @code{CODE} @var{attr} @code{+}
4572 @item @code{DATA} @var{attr} @code{+}
4573 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4574 Generates @code{--attr} @var{section-name} @var{attr} in the output
4575 @code{.drectve} section, where @var{attr} is one of @code{READ},
4576 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4577 this and act upon it.
4582 @c man begin SEEALSO dlltool
4583 The Info pages for @file{binutils}.
4590 @cindex ELF file information
4593 @c man title readelf Displays information about ELF files.
4596 @c man begin SYNOPSIS readelf
4597 readelf [@option{-a}|@option{--all}]
4598 [@option{-h}|@option{--file-header}]
4599 [@option{-l}|@option{--program-headers}|@option{--segments}]
4600 [@option{-S}|@option{--section-headers}|@option{--sections}]
4601 [@option{-g}|@option{--section-groups}]
4602 [@option{-t}|@option{--section-details}]
4603 [@option{-e}|@option{--headers}]
4604 [@option{-s}|@option{--syms}|@option{--symbols}]
4605 [@option{--dyn-syms}]
4606 [@option{-n}|@option{--notes}]
4607 [@option{-r}|@option{--relocs}]
4608 [@option{-u}|@option{--unwind}]
4609 [@option{-d}|@option{--dynamic}]
4610 [@option{-V}|@option{--version-info}]
4611 [@option{-A}|@option{--arch-specific}]
4612 [@option{-D}|@option{--use-dynamic}]
4613 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4614 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4615 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4616 [@option{-z}|@option{--decompress}]
4617 [@option{-c}|@option{--archive-index}]
4618 [@option{-w[lLiaprmfFsoRt]}|
4619 @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]]
4620 [@option{--dwarf-depth=@var{n}}]
4621 [@option{--dwarf-start=@var{n}}]
4622 [@option{-I}|@option{--histogram}]
4623 [@option{-v}|@option{--version}]
4624 [@option{-W}|@option{--wide}]
4625 [@option{-H}|@option{--help}]
4626 @var{elffile}@dots{}
4630 @c man begin DESCRIPTION readelf
4632 @command{readelf} displays information about one or more ELF format object
4633 files. The options control what particular information to display.
4635 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4636 64-bit ELF files are supported, as are archives containing ELF files.
4638 This program performs a similar function to @command{objdump} but it
4639 goes into more detail and it exists independently of the @sc{bfd}
4640 library, so if there is a bug in @sc{bfd} then readelf will not be
4645 @c man begin OPTIONS readelf
4647 The long and short forms of options, shown here as alternatives, are
4648 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4654 Equivalent to specifying @option{--file-header},
4655 @option{--program-headers}, @option{--sections}, @option{--symbols},
4656 @option{--relocs}, @option{--dynamic}, @option{--notes} and
4657 @option{--version-info}.
4660 @itemx --file-header
4661 @cindex ELF file header information
4662 Displays the information contained in the ELF header at the start of the
4666 @itemx --program-headers
4668 @cindex ELF program header information
4669 @cindex ELF segment information
4670 Displays the information contained in the file's segment headers, if it
4675 @itemx --section-headers
4676 @cindex ELF section information
4677 Displays the information contained in the file's section headers, if it
4681 @itemx --section-groups
4682 @cindex ELF section group information
4683 Displays the information contained in the file's section groups, if it
4687 @itemx --section-details
4688 @cindex ELF section information
4689 Displays the detailed section information. Implies @option{-S}.
4694 @cindex ELF symbol table information
4695 Displays the entries in symbol table section of the file, if it has one.
4696 If a symbol has version information associated with it then this is
4697 displayed as well. The version string is displayed as a suffix to the
4698 symbol name, preceeded by an @@ character. For example
4699 @samp{foo@@VER_1}. If the version is the default version to be used
4700 when resolving unversioned references to the symbol then it is
4701 displayed as a suffix preceeded by two @@ characters. For example
4702 @samp{foo@@@@VER_2}.
4705 @cindex ELF dynamic symbol table information
4706 Displays the entries in dynamic symbol table section of the file, if it
4707 has one. The output format is the same as the format used by the
4708 @option{--syms} option.
4712 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4717 Displays the contents of the NOTE segments and/or sections, if any.
4721 @cindex ELF reloc information
4722 Displays the contents of the file's relocation section, if it has one.
4726 @cindex unwind information
4727 Displays the contents of the file's unwind section, if it has one. Only
4728 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4729 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4733 @cindex ELF dynamic section information
4734 Displays the contents of the file's dynamic section, if it has one.
4737 @itemx --version-info
4738 @cindex ELF version sections information
4739 Displays the contents of the version sections in the file, it they
4743 @itemx --arch-specific
4744 Displays architecture-specific information in the file, if there
4748 @itemx --use-dynamic
4749 When displaying symbols, this option makes @command{readelf} use the
4750 symbol hash tables in the file's dynamic section, rather than the
4751 symbol table sections.
4753 @item -x <number or name>
4754 @itemx --hex-dump=<number or name>
4755 Displays the contents of the indicated section as a hexadecimal bytes.
4756 A number identifies a particular section by index in the section table;
4757 any other string identifies all sections with that name in the object file.
4759 @item -R <number or name>
4760 @itemx --relocated-dump=<number or name>
4761 Displays the contents of the indicated section as a hexadecimal
4762 bytes. A number identifies a particular section by index in the
4763 section table; any other string identifies all sections with that name
4764 in the object file. The contents of the section will be relocated
4765 before they are displayed.
4767 @item -p <number or name>
4768 @itemx --string-dump=<number or name>
4769 Displays the contents of the indicated section as printable strings.
4770 A number identifies a particular section by index in the section table;
4771 any other string identifies all sections with that name in the object file.
4775 Requests that the section(s) being dumped by @option{x}, @option{R} or
4776 @option{p} options are decompressed before being displayed. If the
4777 section(s) are not compressed then they are displayed as is.
4780 @itemx --archive-index
4781 @cindex Archive file symbol index information
4782 Displays the file symbol index information contained in the header part
4783 of binary archives. Performs the same function as the @option{t}
4784 command to @command{ar}, but without using the BFD library. @xref{ar}.
4786 @item -w[lLiaprmfFsoRt]
4787 @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]
4788 Displays the contents of the debug sections in the file, if any are
4789 present. If one of the optional letters or words follows the switch
4790 then only data found in those specific sections will be dumped.
4792 Note that there is no single letter option to display the content of
4793 trace sections or .gdb_index.
4795 Note: the @option{=decodedline} option will display the interpreted
4796 contents of a .debug_line section whereas the @option{=rawline} option
4797 dumps the contents in a raw format.
4799 Note: the @option{=frames-interp} option will display the interpreted
4800 contents of a .debug_frame section whereas the @option{=frames} option
4801 dumps the contents in a raw format.
4803 Note: the output from the @option{=info} option can also be affected
4804 by the options @option{--dwarf-depth} and @option{--dwarf-start}.
4806 @item --dwarf-depth=@var{n}
4807 Limit the dump of the @code{.debug_info} section to @var{n} children.
4808 This is only useful with @option{--debug-dump=info}. The default is
4809 to print all DIEs; the special value 0 for @var{n} will also have this
4812 With a non-zero value for @var{n}, DIEs at or deeper than @var{n}
4813 levels will not be printed. The range for @var{n} is zero-based.
4815 @item --dwarf-start=@var{n}
4816 Print only DIEs beginning with the DIE numbered @var{n}. This is only
4817 useful with @option{--debug-dump=info}.
4819 If specified, this option will suppress printing of any header
4820 information and all DIEs before the DIE numbered @var{n}. Only
4821 siblings and children of the specified DIE will be printed.
4823 This can be used in conjunction with @option{--dwarf-depth}.
4827 Display a histogram of bucket list lengths when displaying the contents
4828 of the symbol tables.
4832 Display the version number of readelf.
4836 Don't break output lines to fit into 80 columns. By default
4837 @command{readelf} breaks section header and segment listing lines for
4838 64-bit ELF files, so that they fit into 80 columns. This option causes
4839 @command{readelf} to print each section header resp. each segment one a
4840 single line, which is far more readable on terminals wider than 80 columns.
4844 Display the command line options understood by @command{readelf}.
4851 @c man begin SEEALSO readelf
4852 objdump(1), and the Info entries for @file{binutils}.
4859 @cindex Update ELF header
4862 @c man title elfedit Update the ELF header of ELF files.
4865 @c man begin SYNOPSIS elfedit
4866 elfedit [@option{--input-mach=}@var{machine}]
4867 [@option{--input-type=}@var{type}]
4868 [@option{--input-osabi=}@var{osabi}]
4869 @option{--output-mach=}@var{machine}
4870 @option{--output-type=}@var{type}
4871 @option{--output-osabi=}@var{osabi}
4872 [@option{-v}|@option{--version}]
4873 [@option{-h}|@option{--help}]
4874 @var{elffile}@dots{}
4878 @c man begin DESCRIPTION elfedit
4880 @command{elfedit} updates the ELF header of ELF files which have
4881 the matching ELF machine and file types. The options control how and
4882 which fields in the ELF header should be updated.
4884 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4885 64-bit ELF files are supported, as are archives containing ELF files.
4888 @c man begin OPTIONS elfedit
4890 The long and short forms of options, shown here as alternatives, are
4891 equivalent. At least one of the @option{--output-mach},
4892 @option{--output-type} and @option{--output-osabi} options must be given.
4896 @item --input-mach=@var{machine}
4897 Set the matching input ELF machine type to @var{machine}. If
4898 @option{--input-mach} isn't specified, it will match any ELF
4901 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4902 @var{K1OM} and @var{x86-64}.
4904 @item --output-mach=@var{machine}
4905 Change the ELF machine type in the ELF header to @var{machine}. The
4906 supported ELF machine types are the same as @option{--input-mach}.
4908 @item --input-type=@var{type}
4909 Set the matching input ELF file type to @var{type}. If
4910 @option{--input-type} isn't specified, it will match any ELF file types.
4912 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4914 @item --output-type=@var{type}
4915 Change the ELF file type in the ELF header to @var{type}. The
4916 supported ELF types are the same as @option{--input-type}.
4918 @item --input-osabi=@var{osabi}
4919 Set the matching input ELF file OSABI to @var{osabi}. If
4920 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4922 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4923 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4924 @var{Solaris}, @var{AIX}, @var{Irix},
4925 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4926 @var{NSK}, @var{AROS} and @var{FenixOS}.
4928 @item --output-osabi=@var{osabi}
4929 Change the ELF OSABI in the ELF header to @var{osabi}. The
4930 supported ELF OSABI are the same as @option{--input-osabi}.
4934 Display the version number of @command{elfedit}.
4938 Display the command line options understood by @command{elfedit}.
4945 @c man begin SEEALSO elfedit
4946 readelf(1), and the Info entries for @file{binutils}.
4950 @node Common Options
4951 @chapter Common Options
4953 The following command-line options are supported by all of the
4954 programs described in this manual.
4956 @c man begin OPTIONS
4958 @include at-file.texi
4962 Display the command-line options supported by the program.
4965 Display the version number of the program.
4967 @c man begin OPTIONS
4971 @node Selecting the Target System
4972 @chapter Selecting the Target System
4974 You can specify two aspects of the target system to the @sc{gnu}
4975 binary file utilities, each in several ways:
4985 In the following summaries, the lists of ways to specify values are in
4986 order of decreasing precedence. The ways listed first override those
4989 The commands to list valid values only list the values for which the
4990 programs you are running were configured. If they were configured with
4991 @option{--enable-targets=all}, the commands list most of the available
4992 values, but a few are left out; not all targets can be configured in at
4993 once because some of them can only be configured @dfn{native} (on hosts
4994 with the same type as the target system).
4997 * Target Selection::
4998 * Architecture Selection::
5001 @node Target Selection
5002 @section Target Selection
5004 A @dfn{target} is an object file format. A given target may be
5005 supported for multiple architectures (@pxref{Architecture Selection}).
5006 A target selection may also have variations for different operating
5007 systems or architectures.
5009 The command to list valid target values is @samp{objdump -i}
5010 (the first column of output contains the relevant information).
5012 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5013 @samp{a.out-sunos-big}.
5015 You can also specify a target using a configuration triplet. This is
5016 the same sort of name that is passed to @file{configure} to specify a
5017 target. When you use a configuration triplet as an argument, it must be
5018 fully canonicalized. You can see the canonical version of a triplet by
5019 running the shell script @file{config.sub} which is included with the
5022 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5023 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5025 @subheading @command{objdump} Target
5031 command line option: @option{-b} or @option{--target}
5034 environment variable @code{GNUTARGET}
5037 deduced from the input file
5040 @subheading @command{objcopy} and @command{strip} Input Target
5046 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5049 environment variable @code{GNUTARGET}
5052 deduced from the input file
5055 @subheading @command{objcopy} and @command{strip} Output Target
5061 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5064 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5067 environment variable @code{GNUTARGET}
5070 deduced from the input file
5073 @subheading @command{nm}, @command{size}, and @command{strings} Target
5079 command line option: @option{--target}
5082 environment variable @code{GNUTARGET}
5085 deduced from the input file
5088 @node Architecture Selection
5089 @section Architecture Selection
5091 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5092 to run. Its name may contain a colon, separating the name of the
5093 processor family from the name of the particular @sc{cpu}.
5095 The command to list valid architecture values is @samp{objdump -i} (the
5096 second column contains the relevant information).
5098 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5100 @subheading @command{objdump} Architecture
5106 command line option: @option{-m} or @option{--architecture}
5109 deduced from the input file
5112 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5118 deduced from the input file
5121 @node Reporting Bugs
5122 @chapter Reporting Bugs
5124 @cindex reporting bugs
5126 Your bug reports play an essential role in making the binary utilities
5129 Reporting a bug may help you by bringing a solution to your problem, or
5130 it may not. But in any case the principal function of a bug report is
5131 to help the entire community by making the next version of the binary
5132 utilities work better. Bug reports are your contribution to their
5135 In order for a bug report to serve its purpose, you must include the
5136 information that enables us to fix the bug.
5139 * Bug Criteria:: Have you found a bug?
5140 * Bug Reporting:: How to report bugs
5144 @section Have You Found a Bug?
5145 @cindex bug criteria
5147 If you are not sure whether you have found a bug, here are some guidelines:
5150 @cindex fatal signal
5153 If a binary utility gets a fatal signal, for any input whatever, that is
5154 a bug. Reliable utilities never crash.
5156 @cindex error on valid input
5158 If a binary utility produces an error message for valid input, that is a
5162 If you are an experienced user of binary utilities, your suggestions for
5163 improvement are welcome in any case.
5167 @section How to Report Bugs
5169 @cindex bugs, reporting
5171 A number of companies and individuals offer support for @sc{gnu}
5172 products. If you obtained the binary utilities from a support
5173 organization, we recommend you contact that organization first.
5175 You can find contact information for many support companies and
5176 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5180 In any event, we also recommend that you send bug reports for the binary
5181 utilities to @value{BUGURL}.
5184 The fundamental principle of reporting bugs usefully is this:
5185 @strong{report all the facts}. If you are not sure whether to state a
5186 fact or leave it out, state it!
5188 Often people omit facts because they think they know what causes the
5189 problem and assume that some details do not matter. Thus, you might
5190 assume that the name of a file you use in an example does not matter.
5191 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5192 a stray memory reference which happens to fetch from the location where
5193 that pathname is stored in memory; perhaps, if the pathname were
5194 different, the contents of that location would fool the utility into
5195 doing the right thing despite the bug. Play it safe and give a
5196 specific, complete example. That is the easiest thing for you to do,
5197 and the most helpful.
5199 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5200 it is new to us. Therefore, always write your bug reports on the assumption
5201 that the bug has not been reported previously.
5203 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5204 bell?'' This cannot help us fix a bug, so it is basically useless. We
5205 respond by asking for enough details to enable us to investigate.
5206 You might as well expedite matters by sending them to begin with.
5208 To enable us to fix the bug, you should include all these things:
5212 The version of the utility. Each utility announces it if you start it
5213 with the @option{--version} argument.
5215 Without this, we will not know whether there is any point in looking for
5216 the bug in the current version of the binary utilities.
5219 Any patches you may have applied to the source, including any patches
5220 made to the @code{BFD} library.
5223 The type of machine you are using, and the operating system name and
5227 What compiler (and its version) was used to compile the utilities---e.g.
5231 The command arguments you gave the utility to observe the bug. To
5232 guarantee you will not omit something important, list them all. A copy
5233 of the Makefile (or the output from make) is sufficient.
5235 If we were to try to guess the arguments, we would probably guess wrong
5236 and then we might not encounter the bug.
5239 A complete input file, or set of input files, that will reproduce the
5240 bug. If the utility is reading an object file or files, then it is
5241 generally most helpful to send the actual object files.
5243 If the source files were produced exclusively using @sc{gnu} programs
5244 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5245 may be OK to send the source files rather than the object files. In
5246 this case, be sure to say exactly what version of @command{gcc}, or
5247 whatever, was used to produce the object files. Also say how
5248 @command{gcc}, or whatever, was configured.
5251 A description of what behavior you observe that you believe is
5252 incorrect. For example, ``It gets a fatal signal.''
5254 Of course, if the bug is that the utility gets a fatal signal, then we
5255 will certainly notice it. But if the bug is incorrect output, we might
5256 not notice unless it is glaringly wrong. You might as well not give us
5257 a chance to make a mistake.
5259 Even if the problem you experience is a fatal signal, you should still
5260 say so explicitly. Suppose something strange is going on, such as your
5261 copy of the utility is out of sync, or you have encountered a bug in
5262 the C library on your system. (This has happened!) Your copy might
5263 crash and ours would not. If you told us to expect a crash, then when
5264 ours fails to crash, we would know that the bug was not happening for
5265 us. If you had not told us to expect a crash, then we would not be able
5266 to draw any conclusion from our observations.
5269 If you wish to suggest changes to the source, send us context diffs, as
5270 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5271 option. Always send diffs from the old file to the new file. If you
5272 wish to discuss something in the @command{ld} source, refer to it by
5273 context, not by line number.
5275 The line numbers in our development sources will not match those in your
5276 sources. Your line numbers would convey no useful information to us.
5279 Here are some things that are not necessary:
5283 A description of the envelope of the bug.
5285 Often people who encounter a bug spend a lot of time investigating
5286 which changes to the input file will make the bug go away and which
5287 changes will not affect it.
5289 This is often time consuming and not very useful, because the way we
5290 will find the bug is by running a single example under the debugger
5291 with breakpoints, not by pure deduction from a series of examples.
5292 We recommend that you save your time for something else.
5294 Of course, if you can find a simpler example to report @emph{instead}
5295 of the original one, that is a convenience for us. Errors in the
5296 output will be easier to spot, running under the debugger will take
5297 less time, and so on.
5299 However, simplification is not vital; if you do not want to do this,
5300 report the bug anyway and send us the entire test case you used.
5303 A patch for the bug.
5305 A patch for the bug does help us if it is a good one. But do not omit
5306 the necessary information, such as the test case, on the assumption that
5307 a patch is all we need. We might see problems with your patch and decide
5308 to fix the problem another way, or we might not understand it at all.
5310 Sometimes with programs as complicated as the binary utilities it is
5311 very hard to construct an example that will make the program follow a
5312 certain path through the code. If you do not send us the example, we
5313 will not be able to construct one, so we will not be able to verify that
5316 And if we cannot understand what bug you are trying to fix, or why your
5317 patch should be an improvement, we will not install it. A test case will
5318 help us to understand.
5321 A guess about what the bug is or what it depends on.
5323 Such guesses are usually wrong. Even we cannot guess right about such
5324 things without first using the debugger to find the facts.
5327 @node GNU Free Documentation License
5328 @appendix GNU Free Documentation License
5332 @node Binutils Index
5333 @unnumbered Binutils Index