1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2018 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 * nm: (binutils)nm. List symbols from object files.
38 * objcopy: (binutils)objcopy. Copy and translate object files.
39 * objdump: (binutils)objdump. Display information from object files.
40 * ranlib: (binutils)ranlib. Generate index to archive contents.
41 * readelf: (binutils)readelf. Display the contents of ELF format files.
42 * size: (binutils)size. List section sizes and total size.
43 * strings: (binutils)strings. List printable strings from files.
44 * strip: (binutils)strip. Discard symbols.
45 * elfedit: (binutils)elfedit. Update the ELF header of ELF files.
46 * windmc: (binutils)windmc. Generator for Windows message resources.
47 * windres: (binutils)windres. Manipulate Windows resources.
51 @title The @sc{gnu} Binary Utilities
52 @ifset VERSION_PACKAGE
53 @subtitle @value{VERSION_PACKAGE}
55 @subtitle Version @value{VERSION}
57 @subtitle @value{UPDATED}
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 Texinfo \texinfoversion\par }
68 @vskip 0pt plus 1filll
77 This brief manual contains documentation for the @sc{gnu} binary
79 @ifset VERSION_PACKAGE
80 @value{VERSION_PACKAGE}
82 version @value{VERSION}:
87 Create, modify, and extract from archives
90 List symbols from object files
93 Copy and translate object files
96 Display information from object files
99 Generate index to archive contents
102 Display the contents of ELF format files.
105 List file section sizes and total size
108 List printable strings from files
114 Update the ELF header of ELF files.
117 Demangle encoded C++ symbols (on MS-DOS, this program is named
121 Convert addresses into file names and line numbers
124 Manipulate Windows resources
127 Generator for Windows message resources
130 Create the files needed to build and use Dynamic Link Libraries
134 This document is distributed under the terms of the GNU Free
135 Documentation License version 1.3. A copy of the license is included
136 in the section entitled ``GNU Free Documentation License''.
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * size:: List section sizes and total size
145 * strings:: List printable strings from files
146 * strip:: Discard symbols
147 * c++filt:: Filter to demangle encoded C++ symbols
148 * cxxfilt: c++filt. MS-DOS name for c++filt
149 * addr2line:: Convert addresses to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update the ELF header of ELF files
155 * Common Options:: Command-line options for all utilities
156 * Selecting the Target System:: How these utilities determine the target
157 * Reporting Bugs:: Reporting Bugs
158 * GNU Free Documentation License:: GNU Free Documentation License
159 * Binutils Index:: Binutils Index
167 @cindex collections of files
169 @c man title ar create, modify, and extract from archives
172 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
173 ar -M [ <mri-script ]
176 @c man begin DESCRIPTION ar
178 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
179 archives. An @dfn{archive} is a single file holding a collection of
180 other files in a structure that makes it possible to retrieve
181 the original individual files (called @dfn{members} of the archive).
183 The original files' contents, mode (permissions), timestamp, owner, and
184 group are preserved in the archive, and can be restored on
188 @sc{gnu} @command{ar} can maintain archives whose members have names of any
189 length; however, depending on how @command{ar} is configured on your
190 system, a limit on member-name length may be imposed for compatibility
191 with archive formats maintained with other tools. If it exists, the
192 limit is often 15 characters (typical of formats related to a.out) or 16
193 characters (typical of formats related to coff).
196 @command{ar} is considered a binary utility because archives of this sort
197 are most often used as @dfn{libraries} holding commonly needed
201 @command{ar} creates an index to the symbols defined in relocatable
202 object modules in the archive when you specify the modifier @samp{s}.
203 Once created, this index is updated in the archive whenever @command{ar}
204 makes a change to its contents (save for the @samp{q} update operation).
205 An archive with such an index speeds up linking to the library, and
206 allows routines in the library to call each other without regard to
207 their placement in the archive.
209 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
210 table. If an archive lacks the table, another form of @command{ar} called
211 @command{ranlib} can be used to add just the table.
213 @cindex thin archives
214 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
215 which contains a symbol index and references to the original copies
216 of the member files of the archive. This is useful for building
217 libraries for use within a local build tree, where the relocatable
218 objects are expected to remain available, and copying the contents of
219 each object would only waste time and space.
221 An archive can either be @emph{thin} or it can be normal. It cannot
222 be both at the same time. Once an archive is created its format
223 cannot be changed without first deleting it and then creating a new
224 archive in its place.
226 Thin archives are also @emph{flattened}, so that adding one thin
227 archive to another thin archive does not nest it, as would happen with
228 a normal archive. Instead the elements of the first archive are added
229 individually to the second archive.
231 The paths to the elements of the archive are stored relative to the
234 @cindex compatibility, @command{ar}
235 @cindex @command{ar} compatibility
236 @sc{gnu} @command{ar} is designed to be compatible with two different
237 facilities. You can control its activity using command-line options,
238 like the different varieties of @command{ar} on Unix systems; or, if you
239 specify the single command-line option @option{-M}, you can control it
240 with a script supplied via standard input, like the MRI ``librarian''
246 * ar cmdline:: Controlling @command{ar} on the command line
247 * ar scripts:: Controlling @command{ar} with a script
252 @section Controlling @command{ar} on the Command Line
255 @c man begin SYNOPSIS ar
256 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
260 @cindex Unix compatibility, @command{ar}
261 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
262 arguments to execute: one keyletter specifying the @emph{operation}
263 (optionally accompanied by other keyletters specifying
264 @emph{modifiers}), and the archive name to act on.
266 Most operations can also accept further @var{member} arguments,
267 specifying particular files to operate on.
269 @c man begin OPTIONS ar
271 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
272 flags @var{mod} in any order, within the first command-line argument.
274 If you wish, you may begin the first command-line argument with a
277 @cindex operations on archive
278 The @var{p} keyletter specifies what operation to execute; it may be
279 any of the following, but you must specify only one of them:
283 @cindex deleting from archive
284 @emph{Delete} modules from the archive. Specify the names of modules to
285 be deleted as @var{member}@dots{}; the archive is untouched if you
286 specify no files to delete.
288 If you specify the @samp{v} modifier, @command{ar} lists each module
292 @cindex moving in archive
293 Use this operation to @emph{move} members in an archive.
295 The ordering of members in an archive can make a difference in how
296 programs are linked using the library, if a symbol is defined in more
299 If no modifiers are used with @code{m}, any members you name in the
300 @var{member} arguments are moved to the @emph{end} of the archive;
301 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
302 specified place instead.
305 @cindex printing from archive
306 @emph{Print} the specified members of the archive, to the standard
307 output file. If the @samp{v} modifier is specified, show the member
308 name before copying its contents to standard output.
310 If you specify no @var{member} arguments, all the files in the archive are
314 @cindex quick append to archive
315 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
316 @var{archive}, without checking for replacement.
318 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
319 operation; new members are always placed at the end of the archive.
321 The modifier @samp{v} makes @command{ar} list each file as it is appended.
323 Since the point of this operation is speed, implementations of
324 @command{ar} have the option of not updating the archive's symbol
325 table if one exists. Too many different systems however assume that
326 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
327 rebuild the table even with a quick append.
329 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
330 synonym for @samp{r} - replacing already existing files in the
331 archive and appending new ones at the end.
334 @cindex replacement in archive
335 Insert the files @var{member}@dots{} into @var{archive} (with
336 @emph{replacement}). This operation differs from @samp{q} in that any
337 previously existing members are deleted if their names match those being
340 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
341 displays an error message, and leaves undisturbed any existing members
342 of the archive matching that name.
344 By default, new members are added at the end of the file; but you may
345 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
346 placement relative to some existing member.
348 The modifier @samp{v} used with this operation elicits a line of
349 output for each file inserted, along with one of the letters @samp{a} or
350 @samp{r} to indicate whether the file was appended (no old member
351 deleted) or replaced.
355 Add an index to the archive, or update it if it already exists. Note
356 this command is an exception to the rule that there can only be one
357 command letter, as it is possible to use it as either a command or a
358 modifier. In either case it does the same thing.
361 @cindex contents of archive
362 Display a @emph{table} listing the contents of @var{archive}, or those
363 of the files listed in @var{member}@dots{} that are present in the
364 archive. Normally only the member name is shown, but if the modifier
365 @samp{O} is specified, then the corresponding offset of the member is also
366 displayed. Finally, in order to see the modes (permissions), timestamp,
367 owner, group, and size the @samp{v} modifier should be included.
369 If you do not specify a @var{member}, all files in the archive
372 @cindex repeated names in archive
373 @cindex name duplication in archive
374 If there is more than one file with the same name (say, @samp{fie}) in
375 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
376 first instance; to see them all, you must ask for a complete
377 listing---in our example, @samp{ar t b.a}.
378 @c WRS only; per Gumby, this is implementation-dependent, and in a more
379 @c recent case in fact works the other way.
382 @cindex extract from archive
383 @emph{Extract} members (named @var{member}) from the archive. You can
384 use the @samp{v} modifier with this operation, to request that
385 @command{ar} list each name as it extracts it.
387 If you do not specify a @var{member}, all files in the archive
390 Files cannot be extracted from a thin archive.
393 A number of modifiers (@var{mod}) may immediately follow the @var{p}
394 keyletter, to specify variations on an operation's behavior:
398 @cindex relative placement in archive
399 Add new files @emph{after} an existing member of the
400 archive. If you use the modifier @samp{a}, the name of an existing archive
401 member must be present as the @var{relpos} argument, before the
402 @var{archive} specification.
405 Add new files @emph{before} an existing member of the
406 archive. If you use the modifier @samp{b}, the name of an existing archive
407 member must be present as the @var{relpos} argument, before the
408 @var{archive} specification. (same as @samp{i}).
411 @cindex creating archives
412 @emph{Create} the archive. The specified @var{archive} is always
413 created if it did not exist, when you request an update. But a warning is
414 issued unless you specify in advance that you expect to create it, by
418 @cindex deterministic archives
419 @kindex --enable-deterministic-archives
420 Operate in @emph{deterministic} mode. When adding files and the archive
421 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
422 for all files. When this option is used, if @command{ar} is used with
423 identical options and identical input files, multiple runs will create
424 identical output files regardless of the input files' owners, groups,
425 file modes, or modification times.
427 If @file{binutils} was configured with
428 @option{--enable-deterministic-archives}, then this mode is on by default.
429 It can be disabled with the @samp{U} modifier, below.
432 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
433 names of any length. This will cause it to create archives which are
434 not compatible with the native @command{ar} program on some systems. If
435 this is a concern, the @samp{f} modifier may be used to truncate file
436 names when putting them in the archive.
439 Insert new files @emph{before} an existing member of the
440 archive. If you use the modifier @samp{i}, the name of an existing archive
441 member must be present as the @var{relpos} argument, before the
442 @var{archive} specification. (same as @samp{b}).
445 This modifier is accepted but not used.
446 @c whaffor ar l modifier??? presumably compat; with
447 @c what???---doc@@cygnus.com, 25jan91
450 Uses the @var{count} parameter. This is used if there are multiple
451 entries in the archive with the same name. Extract or delete instance
452 @var{count} of the given name from the archive.
455 @cindex dates in archive
456 Preserve the @emph{original} dates of members when extracting them. If
457 you do not specify this modifier, files extracted from the archive
458 are stamped with the time of extraction.
461 @cindex offsets of files
462 Display member offsets inside the archive. Use together with the @samp{t}
466 Use the full path name when matching names in the archive. @sc{gnu}
467 @command{ar} can not create an archive with a full path name (such archives
468 are not POSIX complaint), but other archive creators can. This option
469 will cause @sc{gnu} @command{ar} to match file names using a complete path
470 name, which can be convenient when extracting a single file from an
471 archive created by another tool.
474 @cindex writing archive index
475 Write an object-file index into the archive, or update an existing one,
476 even if no other change is made to the archive. You may use this modifier
477 flag either with any operation, or alone. Running @samp{ar s} on an
478 archive is equivalent to running @samp{ranlib} on it.
481 @cindex not writing archive index
482 Do not generate an archive symbol table. This can speed up building a
483 large library in several steps. The resulting archive can not be used
484 with the linker. In order to build a symbol table, you must omit the
485 @samp{S} modifier on the last execution of @samp{ar}, or you must run
486 @samp{ranlib} on the archive.
489 @cindex creating thin archive
490 Make the specified @var{archive} a @emph{thin} archive. If it already
491 exists and is a regular archive, the existing members must be present
492 in the same directory as @var{archive}.
495 @cindex updating an archive
496 Normally, @samp{ar r}@dots{} inserts all files
497 listed into the archive. If you would like to insert @emph{only} those
498 of the files you list that are newer than existing members of the same
499 names, use this modifier. The @samp{u} modifier is allowed only for the
500 operation @samp{r} (replace). In particular, the combination @samp{qu} is
501 not allowed, since checking the timestamps would lose any speed
502 advantage from the operation @samp{q}.
505 @cindex deterministic archives
506 @kindex --enable-deterministic-archives
507 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
508 of the @samp{D} modifier, above: added files and the archive index will
509 get their actual UID, GID, timestamp, and file mode values.
511 This is the default unless @file{binutils} was configured with
512 @option{--enable-deterministic-archives}.
515 This modifier requests the @emph{verbose} version of an operation. Many
516 operations display additional information, such as filenames processed,
517 when the modifier @samp{v} is appended.
520 This modifier shows the version number of @command{ar}.
523 The @command{ar} program also supports some command-line options which
524 are neither modifiers nor actions, but which do change its behaviour
529 Displays the list of command-line options supported by @command{ar}
533 Displays the version information of @command{ar} and then exits.
536 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
537 compatibility with AIX. The behaviour produced by this option is the
538 default for @sc{gnu} @command{ar}. @command{ar} does not support any
539 of the other @samp{-X} options; in particular, it does not support
540 @option{-X32} which is the default for AIX @command{ar}.
542 @item --plugin @var{name}
544 The optional command-line switch @option{--plugin @var{name}} causes
545 @command{ar} to load the plugin called @var{name} which adds support
546 for more file formats, including object files with link-time
547 optimization information.
549 This option is only available if the toolchain has been built with
550 plugin support enabled.
552 If @option{--plugin} is not provided, but plugin support has been
553 enabled then @command{ar} iterates over the files in
554 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
555 plugin that claims the object in question is used.
557 Please note that this plugin search directory is @emph{not} the one
558 used by @command{ld}'s @option{-plugin} option. In order to make
559 @command{ar} use the linker plugin it must be copied into the
560 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
561 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
562 based compilations it is called @file{LLVMgold.so}. The GCC plugin
563 is always backwards compatible with earlier versions, so it is
564 sufficient to just copy the newest one.
566 @item --target @var{target}
567 The optional command-line switch @option{--target @var{bfdname}}
568 specifies that the archive members are in an object code format
569 different from your system's default format. See
570 @xref{Target Selection}, for more information.
575 @c man begin SEEALSO ar
576 nm(1), ranlib(1), and the Info entries for @file{binutils}.
581 @section Controlling @command{ar} with a Script
584 ar -M [ <@var{script} ]
587 @cindex MRI compatibility, @command{ar}
588 @cindex scripts, @command{ar}
589 If you use the single command-line option @samp{-M} with @command{ar}, you
590 can control its operation with a rudimentary command language. This
591 form of @command{ar} operates interactively if standard input is coming
592 directly from a terminal. During interactive use, @command{ar} prompts for
593 input (the prompt is @samp{AR >}), and continues executing even after
594 errors. If you redirect standard input to a script file, no prompts are
595 issued, and @command{ar} abandons execution (with a nonzero exit code)
598 The @command{ar} command language is @emph{not} designed to be equivalent
599 to the command-line options; in fact, it provides somewhat less control
600 over archives. The only purpose of the command language is to ease the
601 transition to @sc{gnu} @command{ar} for developers who already have scripts
602 written for the MRI ``librarian'' program.
604 The syntax for the @command{ar} command language is straightforward:
607 commands are recognized in upper or lower case; for example, @code{LIST}
608 is the same as @code{list}. In the following descriptions, commands are
609 shown in upper case for clarity.
612 a single command may appear on each line; it is the first word on the
616 empty lines are allowed, and have no effect.
619 comments are allowed; text after either of the characters @samp{*}
620 or @samp{;} is ignored.
623 Whenever you use a list of names as part of the argument to an @command{ar}
624 command, you can separate the individual names with either commas or
625 blanks. Commas are shown in the explanations below, for clarity.
628 @samp{+} is used as a line continuation character; if @samp{+} appears
629 at the end of a line, the text on the following line is considered part
630 of the current command.
633 Here are the commands you can use in @command{ar} scripts, or when using
634 @command{ar} interactively. Three of them have special significance:
636 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
637 a temporary file required for most of the other commands.
639 @code{SAVE} commits the changes so far specified by the script. Prior
640 to @code{SAVE}, commands affect only the temporary copy of the current
644 @item ADDLIB @var{archive}
645 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
646 Add all the contents of @var{archive} (or, if specified, each named
647 @var{module} from @var{archive}) to the current archive.
649 Requires prior use of @code{OPEN} or @code{CREATE}.
651 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
652 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
653 @c else like "ar q..."
654 Add each named @var{member} as a module in the current archive.
656 Requires prior use of @code{OPEN} or @code{CREATE}.
659 Discard the contents of the current archive, canceling the effect of
660 any operations since the last @code{SAVE}. May be executed (with no
661 effect) even if no current archive is specified.
663 @item CREATE @var{archive}
664 Creates an archive, and makes it the current archive (required for many
665 other commands). The new archive is created with a temporary name; it
666 is not actually saved as @var{archive} until you use @code{SAVE}.
667 You can overwrite existing archives; similarly, the contents of any
668 existing file named @var{archive} will not be destroyed until @code{SAVE}.
670 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
671 Delete each listed @var{module} from the current archive; equivalent to
672 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
674 Requires prior use of @code{OPEN} or @code{CREATE}.
676 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
677 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
678 List each named @var{module} present in @var{archive}. The separate
679 command @code{VERBOSE} specifies the form of the output: when verbose
680 output is off, output is like that of @samp{ar -t @var{archive}
681 @var{module}@dots{}}. When verbose output is on, the listing is like
682 @samp{ar -tv @var{archive} @var{module}@dots{}}.
684 Output normally goes to the standard output stream; however, if you
685 specify @var{outputfile} as a final argument, @command{ar} directs the
689 Exit from @command{ar}, with a @code{0} exit code to indicate successful
690 completion. This command does not save the output file; if you have
691 changed the current archive since the last @code{SAVE} command, those
694 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
695 Extract each named @var{module} from the current archive, writing them
696 into the current directory as separate files. Equivalent to @samp{ar -x
697 @var{archive} @var{module}@dots{}}.
699 Requires prior use of @code{OPEN} or @code{CREATE}.
702 @c FIXME Tokens but no commands???
709 Display full contents of the current archive, in ``verbose'' style
710 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
711 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
712 enhancement, rather than present for MRI compatibility.)
714 Requires prior use of @code{OPEN} or @code{CREATE}.
716 @item OPEN @var{archive}
717 Opens an existing archive for use as the current archive (required for
718 many other commands). Any changes as the result of subsequent commands
719 will not actually affect @var{archive} until you next use @code{SAVE}.
721 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
722 In the current archive, replace each existing @var{module} (named in
723 the @code{REPLACE} arguments) from files in the current working directory.
724 To execute this command without errors, both the file, and the module in
725 the current archive, must exist.
727 Requires prior use of @code{OPEN} or @code{CREATE}.
730 Toggle an internal flag governing the output from @code{DIRECTORY}.
731 When the flag is on, @code{DIRECTORY} output matches output from
732 @samp{ar -tv }@dots{}.
735 Commit your changes to the current archive, and actually save it as a
736 file with the name specified in the last @code{CREATE} or @code{OPEN}
739 Requires prior use of @code{OPEN} or @code{CREATE}.
748 The @sc{gnu} linker @command{ld} is now described in a separate manual.
749 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
757 @c man title nm list symbols from object files
760 @c man begin SYNOPSIS nm
761 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
762 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
763 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
764 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
765 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
766 [@option{-n}|@option{-v}|@option{--numeric-sort}]
767 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
768 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
769 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
770 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
771 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
772 [@option{--plugin} @var{name}] [@option{--size-sort}] [@option{--special-syms}]
773 [@option{--synthetic}] [@option{--with-symbol-versions}] [@option{--target=}@var{bfdname}]
774 [@var{objfile}@dots{}]
778 @c man begin DESCRIPTION nm
779 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
780 If no object files are listed as arguments, @command{nm} assumes the file
783 For each symbol, @command{nm} shows:
787 The symbol value, in the radix selected by options (see below), or
788 hexadecimal by default.
791 The symbol type. At least the following types are used; others are, as
792 well, depending on the object file format. If lowercase, the symbol is
793 usually local; if uppercase, the symbol is global (external). There
794 are however a few lowercase symbols that are shown for special global
795 symbols (@code{u}, @code{v} and @code{w}).
797 @c Some more detail on exactly what these symbol types are used for
801 The symbol's value is absolute, and will not be changed by further
806 The symbol is in the BSS data section. This section typically
807 contains zero-initialized or uninitialized data, although the exact
808 behavior is system dependent.
811 The symbol is common. Common symbols are uninitialized data. When
812 linking, multiple common symbols may appear with the same name. If the
813 symbol is defined anywhere, the common symbols are treated as undefined
816 For more details on common symbols, see the discussion of
817 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
822 The symbol is in the initialized data section.
826 The symbol is in an initialized data section for small objects. Some
827 object file formats permit more efficient access to small data objects,
828 such as a global int variable as opposed to a large global array.
831 For PE format files this indicates that the symbol is in a section
832 specific to the implementation of DLLs. For ELF format files this
833 indicates that the symbol is an indirect function. This is a GNU
834 extension to the standard set of ELF symbol types. It indicates a
835 symbol which if referenced by a relocation does not evaluate to its
836 address, but instead must be invoked at runtime. The runtime
837 execution will then return the value to be used in the relocation.
840 The symbol is an indirect reference to another symbol.
843 The symbol is a debugging symbol.
846 The symbols is in a stack unwind section.
850 The symbol is in a read only data section.
854 The symbol is in an uninitialized or zero-initialized data section
859 The symbol is in the text (code) section.
862 The symbol is undefined.
865 The symbol is a unique global symbol. This is a GNU extension to the
866 standard set of ELF symbol bindings. For such a symbol the dynamic linker
867 will make sure that in the entire process there is just one symbol with
868 this name and type in use.
872 The symbol is a weak object. When a weak defined symbol is linked with
873 a normal defined symbol, the normal defined symbol is used with no error.
874 When a weak undefined symbol is linked and the symbol is not defined,
875 the value of the weak symbol becomes zero with no error. On some
876 systems, uppercase indicates that a default value has been specified.
880 The symbol is a weak symbol that has not been specifically tagged as a
881 weak object symbol. When a weak defined symbol is linked with a normal
882 defined symbol, the normal defined symbol is used with no error.
883 When a weak undefined symbol is linked and the symbol is not defined,
884 the value of the symbol is determined in a system-specific manner without
885 error. On some systems, uppercase indicates that a default value has been
889 The symbol is a stabs symbol in an a.out object file. In this case, the
890 next values printed are the stabs other field, the stabs desc field, and
891 the stab type. Stabs symbols are used to hold debugging information.
894 The symbol type is unknown, or object file format specific.
903 @c man begin OPTIONS nm
904 The long and short forms of options, shown here as alternatives, are
910 @itemx --print-file-name
911 @cindex input file name
913 @cindex source file name
914 Precede each symbol by the name of the input file (or archive member)
915 in which it was found, rather than identifying the input file once only,
916 before all of its symbols.
920 @cindex debugging symbols
921 Display all symbols, even debugger-only symbols; normally these are not
925 @cindex @command{nm} format
926 @cindex @command{nm} compatibility
927 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
930 @itemx --demangle[=@var{style}]
931 @cindex demangling in nm
932 Decode (@dfn{demangle}) low-level symbol names into user-level names.
933 Besides removing any initial underscore prepended by the system, this
934 makes C++ function names readable. Different compilers have different
935 mangling styles. The optional demangling style argument can be used to
936 choose an appropriate demangling style for your compiler. @xref{c++filt},
937 for more information on demangling.
940 Do not demangle low-level symbol names. This is the default.
944 @cindex dynamic symbols
945 Display the dynamic symbols rather than the normal symbols. This is
946 only meaningful for dynamic objects, such as certain types of shared
949 @item -f @var{format}
950 @itemx --format=@var{format}
951 @cindex @command{nm} format
952 @cindex @command{nm} compatibility
953 Use the output format @var{format}, which can be @code{bsd},
954 @code{sysv}, or @code{posix}. The default is @code{bsd}.
955 Only the first character of @var{format} is significant; it can be
956 either upper or lower case.
960 @cindex external symbols
961 Display only external symbols.
965 Show a summary of the options to @command{nm} and exit.
968 @itemx --line-numbers
969 @cindex symbol line numbers
970 For each symbol, use debugging information to try to find a filename and
971 line number. For a defined symbol, look for the line number of the
972 address of the symbol. For an undefined symbol, look for the line
973 number of a relocation entry which refers to the symbol. If line number
974 information can be found, print it after the other symbol information.
977 @cindex objdump inlines
978 When option @option{-l} is active, if the address belongs to a
979 function that was inlined, then this option causes the source
980 information for all enclosing scopes back to the first non-inlined
981 function to be printed as well. For example, if @code{main} inlines
982 @code{callee1} which inlines @code{callee2}, and address is from
983 @code{callee2}, the source information for @code{callee1} and @code{main}
984 will also be printed.
988 @itemx --numeric-sort
989 Sort symbols numerically by their addresses, rather than alphabetically
994 @cindex sorting symbols
995 Do not bother to sort the symbols in any order; print them in the order
1000 Use the POSIX.2 standard output format instead of the default format.
1001 Equivalent to @samp{-f posix}.
1004 @itemx --reverse-sort
1005 Reverse the order of the sort (whether numeric or alphabetic); let the
1010 Print both value and size of defined symbols for the @code{bsd} output style.
1011 This option has no effect for object formats that do not record symbol
1012 sizes, unless @samp{--size-sort} is also used in which case a
1013 calculated size is displayed.
1016 @itemx --print-armap
1017 @cindex symbol index, listing
1018 When listing symbols from archive members, include the index: a mapping
1019 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1020 contain definitions for which names.
1022 @item -t @var{radix}
1023 @itemx --radix=@var{radix}
1024 Use @var{radix} as the radix for printing the symbol values. It must be
1025 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1028 @itemx --undefined-only
1029 @cindex external symbols
1030 @cindex undefined symbols
1031 Display only undefined symbols (those external to each object file).
1035 Show the version number of @command{nm} and exit.
1038 This option is ignored for compatibility with the AIX version of
1039 @command{nm}. It takes one parameter which must be the string
1040 @option{32_64}. The default mode of AIX @command{nm} corresponds
1041 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1043 @item --defined-only
1044 @cindex external symbols
1045 @cindex undefined symbols
1046 Display only defined symbols for each object file.
1048 @item --plugin @var{name}
1050 Load the plugin called @var{name} to add support for extra target
1051 types. This option is only available if the toolchain has been built
1052 with plugin support enabled.
1054 If @option{--plugin} is not provided, but plugin support has been
1055 enabled then @command{nm} iterates over the files in
1056 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1057 plugin that claims the object in question is used.
1059 Please note that this plugin search directory is @emph{not} the one
1060 used by @command{ld}'s @option{-plugin} option. In order to make
1061 @command{nm} use the linker plugin it must be copied into the
1062 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1063 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1064 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1065 is always backwards compatible with earlier versions, so it is
1066 sufficient to just copy the newest one.
1069 Sort symbols by size. For ELF objects symbol sizes are read from the
1070 ELF, for other object types the symbol sizes are computed as the
1071 difference between the value of the symbol and the value of the symbol
1072 with the next higher value. If the @code{bsd} output format is used
1073 the size of the symbol is printed, rather than the value, and
1074 @samp{-S} must be used in order both size and value to be printed.
1076 @item --special-syms
1077 Display symbols which have a target-specific special meaning. These
1078 symbols are usually used by the target for some special processing and
1079 are not normally helpful when included in the normal symbol lists.
1080 For example for ARM targets this option would skip the mapping symbols
1081 used to mark transitions between ARM code, THUMB code and data.
1084 Include synthetic symbols in the output. These are special symbols
1085 created by the linker for various purposes. They are not shown by
1086 default since they are not part of the binary's original source code.
1088 @item --with-symbol-versions
1089 Enables the display of symbol version information if any exists. The
1090 version string is displayed as a suffix to the symbol name, preceeded by
1091 an @@ character. For example @samp{foo@@VER_1}. If the version is
1092 the default version to be used when resolving unversioned references
1093 to the symbol then it is displayed as a suffix preceeded by two @@
1094 characters. For example @samp{foo@@@@VER_2}.
1096 @item --target=@var{bfdname}
1097 @cindex object code format
1098 Specify an object code format other than your system's default format.
1099 @xref{Target Selection}, for more information.
1106 @c man begin SEEALSO nm
1107 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1114 @c man title objcopy copy and translate object files
1117 @c man begin SYNOPSIS objcopy
1118 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1119 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1120 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1121 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1122 [@option{-S}|@option{--strip-all}]
1123 [@option{-g}|@option{--strip-debug}]
1124 [@option{--strip-unneeded}]
1125 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1126 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1127 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1128 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1129 [@option{--localize-hidden}]
1130 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1131 [@option{--globalize-symbol=}@var{symbolname}]
1132 [@option{--globalize-symbols=}@var{filename}]
1133 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1134 [@option{-w}|@option{--wildcard}]
1135 [@option{-x}|@option{--discard-all}]
1136 [@option{-X}|@option{--discard-locals}]
1137 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1138 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1139 [@option{--interleave-width=}@var{width}]
1140 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1141 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1142 [@option{--remove-relocations=}@var{sectionpattern}]
1143 [@option{-p}|@option{--preserve-dates}]
1144 [@option{-D}|@option{--enable-deterministic-archives}]
1145 [@option{-U}|@option{--disable-deterministic-archives}]
1146 [@option{--debugging}]
1147 [@option{--gap-fill=}@var{val}]
1148 [@option{--pad-to=}@var{address}]
1149 [@option{--set-start=}@var{val}]
1150 [@option{--adjust-start=}@var{incr}]
1151 [@option{--change-addresses=}@var{incr}]
1152 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1153 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1154 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1155 [@option{--change-warnings}] [@option{--no-change-warnings}]
1156 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1157 [@option{--add-section} @var{sectionname}=@var{filename}]
1158 [@option{--dump-section} @var{sectionname}=@var{filename}]
1159 [@option{--update-section} @var{sectionname}=@var{filename}]
1160 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1161 [@option{--long-section-names} @{enable,disable,keep@}]
1162 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1163 [@option{--reverse-bytes=}@var{num}]
1164 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1165 [@option{--redefine-sym} @var{old}=@var{new}]
1166 [@option{--redefine-syms=}@var{filename}]
1168 [@option{--keep-symbols=}@var{filename}]
1169 [@option{--strip-symbols=}@var{filename}]
1170 [@option{--strip-unneeded-symbols=}@var{filename}]
1171 [@option{--keep-global-symbols=}@var{filename}]
1172 [@option{--localize-symbols=}@var{filename}]
1173 [@option{--weaken-symbols=}@var{filename}]
1174 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1175 [@option{--alt-machine-code=}@var{index}]
1176 [@option{--prefix-symbols=}@var{string}]
1177 [@option{--prefix-sections=}@var{string}]
1178 [@option{--prefix-alloc-sections=}@var{string}]
1179 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1180 [@option{--keep-file-symbols}]
1181 [@option{--only-keep-debug}]
1182 [@option{--strip-dwo}]
1183 [@option{--extract-dwo}]
1184 [@option{--extract-symbol}]
1185 [@option{--writable-text}]
1186 [@option{--readonly-text}]
1189 [@option{--file-alignment=}@var{num}]
1190 [@option{--heap=}@var{size}]
1191 [@option{--image-base=}@var{address}]
1192 [@option{--section-alignment=}@var{num}]
1193 [@option{--stack=}@var{size}]
1194 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1195 [@option{--compress-debug-sections}]
1196 [@option{--decompress-debug-sections}]
1197 [@option{--elf-stt-common=@var{val}}]
1198 [@option{--merge-notes}]
1199 [@option{--no-merge-notes}]
1200 [@option{-v}|@option{--verbose}]
1201 [@option{-V}|@option{--version}]
1202 [@option{--help}] [@option{--info}]
1203 @var{infile} [@var{outfile}]
1207 @c man begin DESCRIPTION objcopy
1208 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1209 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1210 read and write the object files. It can write the destination object
1211 file in a format different from that of the source object file. The
1212 exact behavior of @command{objcopy} is controlled by command-line options.
1213 Note that @command{objcopy} should be able to copy a fully linked file
1214 between any two formats. However, copying a relocatable object file
1215 between any two formats may not work as expected.
1217 @command{objcopy} creates temporary files to do its translations and
1218 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1219 translation work; it has access to all the formats described in @sc{bfd}
1220 and thus is able to recognize most formats without being told
1221 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1223 @command{objcopy} can be used to generate S-records by using an output
1224 target of @samp{srec} (e.g., use @samp{-O srec}).
1226 @command{objcopy} can be used to generate a raw binary file by using an
1227 output target of @samp{binary} (e.g., use @option{-O binary}). When
1228 @command{objcopy} generates a raw binary file, it will essentially produce
1229 a memory dump of the contents of the input object file. All symbols and
1230 relocation information will be discarded. The memory dump will start at
1231 the load address of the lowest section copied into the output file.
1233 When generating an S-record or a raw binary file, it may be helpful to
1234 use @option{-S} to remove sections containing debugging information. In
1235 some cases @option{-R} will be useful to remove sections which contain
1236 information that is not needed by the binary file.
1238 Note---@command{objcopy} is not able to change the endianness of its input
1239 files. If the input format has an endianness (some formats do not),
1240 @command{objcopy} can only copy the inputs into file formats that have the
1241 same endianness or which have no endianness (e.g., @samp{srec}).
1242 (However, see the @option{--reverse-bytes} option.)
1246 @c man begin OPTIONS objcopy
1250 @itemx @var{outfile}
1251 The input and output files, respectively.
1252 If you do not specify @var{outfile}, @command{objcopy} creates a
1253 temporary file and destructively renames the result with
1254 the name of @var{infile}.
1256 @item -I @var{bfdname}
1257 @itemx --input-target=@var{bfdname}
1258 Consider the source file's object format to be @var{bfdname}, rather than
1259 attempting to deduce it. @xref{Target Selection}, for more information.
1261 @item -O @var{bfdname}
1262 @itemx --output-target=@var{bfdname}
1263 Write the output file using the object format @var{bfdname}.
1264 @xref{Target Selection}, for more information.
1266 @item -F @var{bfdname}
1267 @itemx --target=@var{bfdname}
1268 Use @var{bfdname} as the object format for both the input and the output
1269 file; i.e., simply transfer data from source to destination with no
1270 translation. @xref{Target Selection}, for more information.
1272 @item -B @var{bfdarch}
1273 @itemx --binary-architecture=@var{bfdarch}
1274 Useful when transforming a architecture-less input file into an object file.
1275 In this case the output architecture can be set to @var{bfdarch}. This
1276 option will be ignored if the input file has a known @var{bfdarch}. You
1277 can access this binary data inside a program by referencing the special
1278 symbols that are created by the conversion process. These symbols are
1279 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1280 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1281 an object file and then access it in your code using these symbols.
1283 @item -j @var{sectionpattern}
1284 @itemx --only-section=@var{sectionpattern}
1285 Copy only the indicated sections from the input file to the output file.
1286 This option may be given more than once. Note that using this option
1287 inappropriately may make the output file unusable. Wildcard
1288 characters are accepted in @var{sectionpattern}.
1290 If the first character of @var{sectionpattern} is the exclamation
1291 point (!) then matching sections will not be copied, even if earlier
1292 use of @option{--only-section} on the same command line would
1293 otherwise copy it. For example:
1296 --only-section=.text.* --only-section=!.text.foo
1299 will copy all sectinos maching '.text.*' but not the section
1302 @item -R @var{sectionpattern}
1303 @itemx --remove-section=@var{sectionpattern}
1304 Remove any section matching @var{sectionpattern} from the output file.
1305 This option may be given more than once. Note that using this option
1306 inappropriately may make the output file unusable. Wildcard
1307 characters are accepted in @var{sectionpattern}. Using both the
1308 @option{-j} and @option{-R} options together results in undefined
1311 If the first character of @var{sectionpattern} is the exclamation
1312 point (!) then matching sections will not be removed even if an
1313 earlier use of @option{--remove-section} on the same command line
1314 would otherwise remove it. For example:
1317 --remove-section=.text.* --remove-section=!.text.foo
1320 will remove all sections matching the pattern '.text.*', but will not
1321 remove the section '.text.foo'.
1323 @item --remove-relocations=@var{sectionpattern}
1324 Remove non-dynamic relocations from the output file for any section
1325 matching @var{sectionpattern}. This option may be given more than
1326 once. Note that using this option inappropriately may make the output
1327 file unusable, and attempting to remove a dynamic relocation section
1328 such as @samp{.rela.plt} from an executable or shared library with
1329 @option{--remove-relocations=.plt} will not work. Wildcard characters
1330 are accepted in @var{sectionpattern}.
1334 --remove-relocations=.text.*
1337 will remove the relocations for all sections matching the pattern
1340 If the first character of @var{sectionpattern} is the exclamation
1341 point (!) then matching sections will not have their relocation
1342 removed even if an earlier use of @option{--remove-relocations} on the
1343 same command line would otherwise cause the relocations to be removed.
1347 --remove-relocations=.text.* --remove-relocations=!.text.foo
1350 will remove all relocations for sections matching the pattern
1351 '.text.*', but will not remove relocations for the section
1356 Do not copy relocation and symbol information from the source file.
1359 @itemx --strip-debug
1360 Do not copy debugging symbols or sections from the source file.
1362 @item --strip-unneeded
1363 Strip all symbols that are not needed for relocation processing.
1365 @item -K @var{symbolname}
1366 @itemx --keep-symbol=@var{symbolname}
1367 When stripping symbols, keep symbol @var{symbolname} even if it would
1368 normally be stripped. This option may be given more than once.
1370 @item -N @var{symbolname}
1371 @itemx --strip-symbol=@var{symbolname}
1372 Do not copy symbol @var{symbolname} from the source file. This option
1373 may be given more than once.
1375 @item --strip-unneeded-symbol=@var{symbolname}
1376 Do not copy symbol @var{symbolname} from the source file unless it is needed
1377 by a relocation. This option may be given more than once.
1379 @item -G @var{symbolname}
1380 @itemx --keep-global-symbol=@var{symbolname}
1381 Keep only symbol @var{symbolname} global. Make all other symbols local
1382 to the file, so that they are not visible externally. This option may
1383 be given more than once. Note: this option cannot be used in
1384 conjunction with the @option{--globalize-symbol} or
1385 @option{--globalize-symbols} options.
1387 @item --localize-hidden
1388 In an ELF object, mark all symbols that have hidden or internal visibility
1389 as local. This option applies on top of symbol-specific localization options
1390 such as @option{-L}.
1392 @item -L @var{symbolname}
1393 @itemx --localize-symbol=@var{symbolname}
1394 Convert a global or weak symbol called @var{symbolname} into a local
1395 symbol, so that it is not visible externally. This option may be
1396 given more than once. Note - unique symbols are not converted.
1398 @item -W @var{symbolname}
1399 @itemx --weaken-symbol=@var{symbolname}
1400 Make symbol @var{symbolname} weak. This option may be given more than once.
1402 @item --globalize-symbol=@var{symbolname}
1403 Give symbol @var{symbolname} global scoping so that it is visible
1404 outside of the file in which it is defined. This option may be given
1405 more than once. Note: this option cannot be used in conjunction with
1406 the @option{-G} or @option{--keep-global-symbol} options.
1410 Permit regular expressions in @var{symbolname}s used in other command
1411 line options. The question mark (?), asterisk (*), backslash (\) and
1412 square brackets ([]) operators can be used anywhere in the symbol
1413 name. If the first character of the symbol name is the exclamation
1414 point (!) then the sense of the switch is reversed for that symbol.
1421 would cause objcopy to weaken all symbols that start with ``fo''
1422 except for the symbol ``foo''.
1425 @itemx --discard-all
1426 Do not copy non-global symbols from the source file.
1427 @c FIXME any reason to prefer "non-global" to "local" here?
1430 @itemx --discard-locals
1431 Do not copy compiler-generated local symbols.
1432 (These usually start with @samp{L} or @samp{.}.)
1435 @itemx --byte=@var{byte}
1436 If interleaving has been enabled via the @option{--interleave} option
1437 then start the range of bytes to keep at the @var{byte}th byte.
1438 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1439 @var{breadth} is the value given by the @option{--interleave} option.
1441 @item -i [@var{breadth}]
1442 @itemx --interleave[=@var{breadth}]
1443 Only copy a range out of every @var{breadth} bytes. (Header data is
1444 not affected). Select which byte in the range begins the copy with
1445 the @option{--byte} option. Select the width of the range with the
1446 @option{--interleave-width} option.
1448 This option is useful for creating files to program @sc{rom}. It is
1449 typically used with an @code{srec} output target. Note that
1450 @command{objcopy} will complain if you do not specify the
1451 @option{--byte} option as well.
1453 The default interleave breadth is 4, so with @option{--byte} set to 0,
1454 @command{objcopy} would copy the first byte out of every four bytes
1455 from the input to the output.
1457 @item --interleave-width=@var{width}
1458 When used with the @option{--interleave} option, copy @var{width}
1459 bytes at a time. The start of the range of bytes to be copied is set
1460 by the @option{--byte} option, and the extent of the range is set with
1461 the @option{--interleave} option.
1463 The default value for this option is 1. The value of @var{width} plus
1464 the @var{byte} value set by the @option{--byte} option must not exceed
1465 the interleave breadth set by the @option{--interleave} option.
1467 This option can be used to create images for two 16-bit flashes interleaved
1468 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1469 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1470 commands. If the input was '12345678' then the outputs would be
1471 '1256' and '3478' respectively.
1474 @itemx --preserve-dates
1475 Set the access and modification dates of the output file to be the same
1476 as those of the input file.
1479 @itemx --enable-deterministic-archives
1480 @cindex deterministic archives
1481 @kindex --enable-deterministic-archives
1482 Operate in @emph{deterministic} mode. When copying archive members
1483 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1484 and use consistent file modes for all files.
1486 If @file{binutils} was configured with
1487 @option{--enable-deterministic-archives}, then this mode is on by default.
1488 It can be disabled with the @samp{-U} option, below.
1491 @itemx --disable-deterministic-archives
1492 @cindex deterministic archives
1493 @kindex --enable-deterministic-archives
1494 Do @emph{not} operate in @emph{deterministic} mode. This is the
1495 inverse of the @option{-D} option, above: when copying archive members
1496 and writing the archive index, use their actual UID, GID, timestamp,
1497 and file mode values.
1499 This is the default unless @file{binutils} was configured with
1500 @option{--enable-deterministic-archives}.
1503 Convert debugging information, if possible. This is not the default
1504 because only certain debugging formats are supported, and the
1505 conversion process can be time consuming.
1507 @item --gap-fill @var{val}
1508 Fill gaps between sections with @var{val}. This operation applies to
1509 the @emph{load address} (LMA) of the sections. It is done by increasing
1510 the size of the section with the lower address, and filling in the extra
1511 space created with @var{val}.
1513 @item --pad-to @var{address}
1514 Pad the output file up to the load address @var{address}. This is
1515 done by increasing the size of the last section. The extra space is
1516 filled in with the value specified by @option{--gap-fill} (default zero).
1518 @item --set-start @var{val}
1519 Set the start address of the new file to @var{val}. Not all object file
1520 formats support setting the start address.
1522 @item --change-start @var{incr}
1523 @itemx --adjust-start @var{incr}
1524 @cindex changing start address
1525 Change the start address by adding @var{incr}. Not all object file
1526 formats support setting the start address.
1528 @item --change-addresses @var{incr}
1529 @itemx --adjust-vma @var{incr}
1530 @cindex changing object addresses
1531 Change the VMA and LMA addresses of all sections, as well as the start
1532 address, by adding @var{incr}. Some object file formats do not permit
1533 section addresses to be changed arbitrarily. Note that this does not
1534 relocate the sections; if the program expects sections to be loaded at a
1535 certain address, and this option is used to change the sections such
1536 that they are loaded at a different address, the program may fail.
1538 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1539 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1540 @cindex changing section address
1541 Set or change both the VMA address and the LMA address of any section
1542 matching @var{sectionpattern}. If @samp{=} is used, the section
1543 address is set to @var{val}. Otherwise, @var{val} is added to or
1544 subtracted from the section address. See the comments under
1545 @option{--change-addresses}, above. If @var{sectionpattern} does not
1546 match any sections in the input file, a warning will be issued, unless
1547 @option{--no-change-warnings} is used.
1549 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1550 @cindex changing section LMA
1551 Set or change the LMA address of any sections matching
1552 @var{sectionpattern}. The LMA address is the address where the
1553 section will be loaded into memory at program load time. Normally
1554 this is the same as the VMA address, which is the address of the
1555 section at program run time, but on some systems, especially those
1556 where a program is held in ROM, the two can be different. If @samp{=}
1557 is used, the section address is set to @var{val}. Otherwise,
1558 @var{val} is added to or subtracted from the section address. See the
1559 comments under @option{--change-addresses}, above. If
1560 @var{sectionpattern} does not match any sections in the input file, a
1561 warning will be issued, unless @option{--no-change-warnings} is used.
1563 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1564 @cindex changing section VMA
1565 Set or change the VMA address of any section matching
1566 @var{sectionpattern}. The VMA address is the address where the
1567 section will be located once the program has started executing.
1568 Normally this is the same as the LMA address, which is the address
1569 where the section will be loaded into memory, but on some systems,
1570 especially those where a program is held in ROM, the two can be
1571 different. If @samp{=} is used, the section address is set to
1572 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1573 section address. See the comments under @option{--change-addresses},
1574 above. If @var{sectionpattern} does not match any sections in the
1575 input file, a warning will be issued, unless
1576 @option{--no-change-warnings} is used.
1578 @item --change-warnings
1579 @itemx --adjust-warnings
1580 If @option{--change-section-address} or @option{--change-section-lma} or
1581 @option{--change-section-vma} is used, and the section pattern does not
1582 match any sections, issue a warning. This is the default.
1584 @item --no-change-warnings
1585 @itemx --no-adjust-warnings
1586 Do not issue a warning if @option{--change-section-address} or
1587 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1588 if the section pattern does not match any sections.
1590 @item --set-section-flags @var{sectionpattern}=@var{flags}
1591 Set the flags for any sections matching @var{sectionpattern}. The
1592 @var{flags} argument is a comma separated string of flag names. The
1593 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1594 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1595 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1596 for a section which does not have contents, but it is not meaningful
1597 to clear the @samp{contents} flag of a section which does have
1598 contents--just remove the section instead. Not all flags are
1599 meaningful for all object file formats.
1601 @item --add-section @var{sectionname}=@var{filename}
1602 Add a new section named @var{sectionname} while copying the file. The
1603 contents of the new section are taken from the file @var{filename}. The
1604 size of the section will be the size of the file. This option only
1605 works on file formats which can support sections with arbitrary names.
1606 Note - it may be necessary to use the @option{--set-section-flags}
1607 option to set the attributes of the newly created section.
1609 @item --dump-section @var{sectionname}=@var{filename}
1610 Place the contents of section named @var{sectionname} into the file
1611 @var{filename}, overwriting any contents that may have been there
1612 previously. This option is the inverse of @option{--add-section}.
1613 This option is similar to the @option{--only-section} option except
1614 that it does not create a formatted file, it just dumps the contents
1615 as raw binary data, without applying any relocations. The option can
1616 be specified more than once.
1618 @item --update-section @var{sectionname}=@var{filename}
1619 Replace the existing contents of a section named @var{sectionname}
1620 with the contents of file @var{filename}. The size of the section
1621 will be adjusted to the size of the file. The section flags for
1622 @var{sectionname} will be unchanged. For ELF format files the section
1623 to segment mapping will also remain unchanged, something which is not
1624 possible using @option{--remove-section} followed by
1625 @option{--add-section}. The option can be specified more than once.
1627 Note - it is possible to use @option{--rename-section} and
1628 @option{--update-section} to both update and rename a section from one
1629 command line. In this case, pass the original section name to
1630 @option{--update-section}, and the original and new section names to
1631 @option{--rename-section}.
1633 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1634 Add a new symbol named @var{name} while copying the file. This option may be
1635 specified multiple times. If the @var{section} is given, the symbol will be
1636 associated with and relative to that section, otherwise it will be an ABS
1637 symbol. Specifying an undefined section will result in a fatal error. There
1638 is no check for the value, it will be taken as specified. Symbol flags can
1639 be specified and not all flags will be meaningful for all object file
1640 formats. By default, the symbol will be global. The special flag
1641 'before=@var{othersym}' will insert the new symbol in front of the specified
1642 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1643 symbol table in the order they appear.
1645 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1646 Rename a section from @var{oldname} to @var{newname}, optionally
1647 changing the section's flags to @var{flags} in the process. This has
1648 the advantage over using a linker script to perform the rename in that
1649 the output stays as an object file and does not become a linked
1652 This option is particularly helpful when the input format is binary,
1653 since this will always create a section called .data. If for example,
1654 you wanted instead to create a section called .rodata containing binary
1655 data you could use the following command line to achieve it:
1658 objcopy -I binary -O <output_format> -B <architecture> \
1659 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1660 <input_binary_file> <output_object_file>
1663 @item --long-section-names @{enable,disable,keep@}
1664 Controls the handling of long section names when processing @code{COFF}
1665 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1666 is to preserve long section names if any are present in the input file.
1667 The @samp{enable} and @samp{disable} options forcibly enable or disable
1668 the use of long section names in the output object; when @samp{disable}
1669 is in effect, any long section names in the input object will be truncated.
1670 The @samp{enable} option will only emit long section names if any are
1671 present in the inputs; this is mostly the same as @samp{keep}, but it
1672 is left undefined whether the @samp{enable} option might force the
1673 creation of an empty string table in the output file.
1675 @item --change-leading-char
1676 Some object file formats use special characters at the start of
1677 symbols. The most common such character is underscore, which compilers
1678 often add before every symbol. This option tells @command{objcopy} to
1679 change the leading character of every symbol when it converts between
1680 object file formats. If the object file formats use the same leading
1681 character, this option has no effect. Otherwise, it will add a
1682 character, or remove a character, or change a character, as
1685 @item --remove-leading-char
1686 If the first character of a global symbol is a special symbol leading
1687 character used by the object file format, remove the character. The
1688 most common symbol leading character is underscore. This option will
1689 remove a leading underscore from all global symbols. This can be useful
1690 if you want to link together objects of different file formats with
1691 different conventions for symbol names. This is different from
1692 @option{--change-leading-char} because it always changes the symbol name
1693 when appropriate, regardless of the object file format of the output
1696 @item --reverse-bytes=@var{num}
1697 Reverse the bytes in a section with output contents. A section length must
1698 be evenly divisible by the value given in order for the swap to be able to
1699 take place. Reversing takes place before the interleaving is performed.
1701 This option is used typically in generating ROM images for problematic
1702 target systems. For example, on some target boards, the 32-bit words
1703 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1704 regardless of the CPU byte order. Depending on the programming model, the
1705 endianness of the ROM may need to be modified.
1707 Consider a simple file with a section containing the following eight
1708 bytes: @code{12345678}.
1710 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1711 output file would be ordered @code{21436587}.
1713 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1714 output file would be ordered @code{43218765}.
1716 By using @samp{--reverse-bytes=2} for the above example, followed by
1717 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1718 output file would be ordered @code{34127856}.
1720 @item --srec-len=@var{ival}
1721 Meaningful only for srec output. Set the maximum length of the Srecords
1722 being produced to @var{ival}. This length covers both address, data and
1725 @item --srec-forceS3
1726 Meaningful only for srec output. Avoid generation of S1/S2 records,
1727 creating S3-only record format.
1729 @item --redefine-sym @var{old}=@var{new}
1730 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1731 when one is trying link two things together for which you have no
1732 source, and there are name collisions.
1734 @item --redefine-syms=@var{filename}
1735 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1736 listed in the file @var{filename}. @var{filename} is simply a flat file,
1737 with one symbol pair per line. Line comments may be introduced by the hash
1738 character. This option may be given more than once.
1741 Change all global symbols in the file to be weak. This can be useful
1742 when building an object which will be linked against other objects using
1743 the @option{-R} option to the linker. This option is only effective when
1744 using an object file format which supports weak symbols.
1746 @item --keep-symbols=@var{filename}
1747 Apply @option{--keep-symbol} option to each symbol listed in the file
1748 @var{filename}. @var{filename} is simply a flat file, with one symbol
1749 name per line. Line comments may be introduced by the hash character.
1750 This option may be given more than once.
1752 @item --strip-symbols=@var{filename}
1753 Apply @option{--strip-symbol} option to each symbol listed in the file
1754 @var{filename}. @var{filename} is simply a flat file, with one symbol
1755 name per line. Line comments may be introduced by the hash character.
1756 This option may be given more than once.
1758 @item --strip-unneeded-symbols=@var{filename}
1759 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1760 the file @var{filename}. @var{filename} is simply a flat file, with one
1761 symbol name per line. Line comments may be introduced by the hash
1762 character. This option may be given more than once.
1764 @item --keep-global-symbols=@var{filename}
1765 Apply @option{--keep-global-symbol} option to each symbol listed in the
1766 file @var{filename}. @var{filename} is simply a flat file, with one
1767 symbol name per line. Line comments may be introduced by the hash
1768 character. This option may be given more than once.
1770 @item --localize-symbols=@var{filename}
1771 Apply @option{--localize-symbol} option to each symbol listed in the file
1772 @var{filename}. @var{filename} is simply a flat file, with one symbol
1773 name per line. Line comments may be introduced by the hash character.
1774 This option may be given more than once.
1776 @item --globalize-symbols=@var{filename}
1777 Apply @option{--globalize-symbol} option to each symbol listed in the file
1778 @var{filename}. @var{filename} is simply a flat file, with one symbol
1779 name per line. Line comments may be introduced by the hash character.
1780 This option may be given more than once. Note: this option cannot be
1781 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1784 @item --weaken-symbols=@var{filename}
1785 Apply @option{--weaken-symbol} option to each symbol listed in the file
1786 @var{filename}. @var{filename} is simply a flat file, with one symbol
1787 name per line. Line comments may be introduced by the hash character.
1788 This option may be given more than once.
1790 @item --alt-machine-code=@var{index}
1791 If the output architecture has alternate machine codes, use the
1792 @var{index}th code instead of the default one. This is useful in case
1793 a machine is assigned an official code and the tool-chain adopts the
1794 new code, but other applications still depend on the original code
1795 being used. For ELF based architectures if the @var{index}
1796 alternative does not exist then the value is treated as an absolute
1797 number to be stored in the e_machine field of the ELF header.
1799 @item --writable-text
1800 Mark the output text as writable. This option isn't meaningful for all
1801 object file formats.
1803 @item --readonly-text
1804 Make the output text write protected. This option isn't meaningful for all
1805 object file formats.
1808 Mark the output file as demand paged. This option isn't meaningful for all
1809 object file formats.
1812 Mark the output file as impure. This option isn't meaningful for all
1813 object file formats.
1815 @item --prefix-symbols=@var{string}
1816 Prefix all symbols in the output file with @var{string}.
1818 @item --prefix-sections=@var{string}
1819 Prefix all section names in the output file with @var{string}.
1821 @item --prefix-alloc-sections=@var{string}
1822 Prefix all the names of all allocated sections in the output file with
1825 @item --add-gnu-debuglink=@var{path-to-file}
1826 Creates a .gnu_debuglink section which contains a reference to
1827 @var{path-to-file} and adds it to the output file. Note: the file at
1828 @var{path-to-file} must exist. Part of the process of adding the
1829 .gnu_debuglink section involves embedding a checksum of the contents
1830 of the debug info file into the section.
1832 If the debug info file is built in one location but it is going to be
1833 installed at a later time into a different location then do not use
1834 the path to the installed location. The @option{--add-gnu-debuglink}
1835 option will fail because the installed file does not exist yet.
1836 Instead put the debug info file in the current directory and use the
1837 @option{--add-gnu-debuglink} option without any directory components,
1841 objcopy --add-gnu-debuglink=foo.debug
1844 At debug time the debugger will attempt to look for the separate debug
1845 info file in a set of known locations. The exact set of these
1846 locations varies depending upon the distribution being used, but it
1851 @item * The same directory as the executable.
1853 @item * A sub-directory of the directory containing the executable
1856 @item * A global debug directory such as /usr/lib/debug.
1859 As long as the debug info file has been installed into one of these
1860 locations before the debugger is run everything should work
1863 @item --keep-file-symbols
1864 When stripping a file, perhaps with @option{--strip-debug} or
1865 @option{--strip-unneeded}, retain any symbols specifying source file names,
1866 which would otherwise get stripped.
1868 @item --only-keep-debug
1869 Strip a file, removing contents of any sections that would not be
1870 stripped by @option{--strip-debug} and leaving the debugging sections
1871 intact. In ELF files, this preserves all note sections in the output.
1873 Note - the section headers of the stripped sections are preserved,
1874 including their sizes, but the contents of the section are discarded.
1875 The section headers are preserved so that other tools can match up the
1876 debuginfo file with the real executable, even if that executable has
1877 been relocated to a different address space.
1879 The intention is that this option will be used in conjunction with
1880 @option{--add-gnu-debuglink} to create a two part executable. One a
1881 stripped binary which will occupy less space in RAM and in a
1882 distribution and the second a debugging information file which is only
1883 needed if debugging abilities are required. The suggested procedure
1884 to create these files is as follows:
1887 @item Link the executable as normal. Assuming that it is called
1889 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1890 create a file containing the debugging info.
1891 @item Run @code{objcopy --strip-debug foo} to create a
1892 stripped executable.
1893 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1894 to add a link to the debugging info into the stripped executable.
1897 Note---the choice of @code{.dbg} as an extension for the debug info
1898 file is arbitrary. Also the @code{--only-keep-debug} step is
1899 optional. You could instead do this:
1902 @item Link the executable as normal.
1903 @item Copy @code{foo} to @code{foo.full}
1904 @item Run @code{objcopy --strip-debug foo}
1905 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1908 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1909 full executable. It does not have to be a file created by the
1910 @option{--only-keep-debug} switch.
1912 Note---this switch is only intended for use on fully linked files. It
1913 does not make sense to use it on object files where the debugging
1914 information may be incomplete. Besides the gnu_debuglink feature
1915 currently only supports the presence of one filename containing
1916 debugging information, not multiple filenames on a one-per-object-file
1920 Remove the contents of all DWARF .dwo sections, leaving the
1921 remaining debugging sections and all symbols intact.
1922 This option is intended for use by the compiler as part of
1923 the @option{-gsplit-dwarf} option, which splits debug information
1924 between the .o file and a separate .dwo file. The compiler
1925 generates all debug information in the same file, then uses
1926 the @option{--extract-dwo} option to copy the .dwo sections to
1927 the .dwo file, then the @option{--strip-dwo} option to remove
1928 those sections from the original .o file.
1931 Extract the contents of all DWARF .dwo sections. See the
1932 @option{--strip-dwo} option for more information.
1934 @item --file-alignment @var{num}
1935 Specify the file alignment. Sections in the file will always begin at
1936 file offsets which are multiples of this number. This defaults to
1938 [This option is specific to PE targets.]
1940 @item --heap @var{reserve}
1941 @itemx --heap @var{reserve},@var{commit}
1942 Specify the number of bytes of memory to reserve (and optionally commit)
1943 to be used as heap for this program.
1944 [This option is specific to PE targets.]
1946 @item --image-base @var{value}
1947 Use @var{value} as the base address of your program or dll. This is
1948 the lowest memory location that will be used when your program or dll
1949 is loaded. To reduce the need to relocate and improve performance of
1950 your dlls, each should have a unique base address and not overlap any
1951 other dlls. The default is 0x400000 for executables, and 0x10000000
1953 [This option is specific to PE targets.]
1955 @item --section-alignment @var{num}
1956 Sets the section alignment. Sections in memory will always begin at
1957 addresses which are a multiple of this number. Defaults to 0x1000.
1958 [This option is specific to PE targets.]
1960 @item --stack @var{reserve}
1961 @itemx --stack @var{reserve},@var{commit}
1962 Specify the number of bytes of memory to reserve (and optionally commit)
1963 to be used as stack for this program.
1964 [This option is specific to PE targets.]
1966 @item --subsystem @var{which}
1967 @itemx --subsystem @var{which}:@var{major}
1968 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1969 Specifies the subsystem under which your program will execute. The
1970 legal values for @var{which} are @code{native}, @code{windows},
1971 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1972 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1973 the subsystem version also. Numeric values are also accepted for
1975 [This option is specific to PE targets.]
1977 @item --extract-symbol
1978 Keep the file's section flags and symbols but remove all section data.
1979 Specifically, the option:
1982 @item removes the contents of all sections;
1983 @item sets the size of every section to zero; and
1984 @item sets the file's start address to zero.
1987 This option is used to build a @file{.sym} file for a VxWorks kernel.
1988 It can also be a useful way of reducing the size of a @option{--just-symbols}
1991 @item --compress-debug-sections
1992 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
1993 ELF ABI. Note - if compression would actually make a section
1994 @emph{larger}, then it is not compressed.
1996 @item --compress-debug-sections=none
1997 @itemx --compress-debug-sections=zlib
1998 @itemx --compress-debug-sections=zlib-gnu
1999 @itemx --compress-debug-sections=zlib-gabi
2000 For ELF files, these options control how DWARF debug sections are
2001 compressed. @option{--compress-debug-sections=none} is equivalent
2002 to @option{--decompress-debug-sections}.
2003 @option{--compress-debug-sections=zlib} and
2004 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2005 @option{--compress-debug-sections}.
2006 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
2007 sections using zlib. The debug sections are renamed to begin with
2008 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
2009 actually make a section @emph{larger}, then it is not compressed nor
2012 @item --decompress-debug-sections
2013 Decompress DWARF debug sections using zlib. The original section
2014 names of the compressed sections are restored.
2016 @item --elf-stt-common=yes
2017 @itemx --elf-stt-common=no
2018 For ELF files, these options control whether common symbols should be
2019 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2020 @option{--elf-stt-common=yes} converts common symbol type to
2021 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2022 type to @code{STT_OBJECT}.
2025 @itemx --no-merge-notes
2026 For ELF files, attempt (or do not attempt) to reduce the size of any
2027 SHT_NOTE type sections by removing duplicate notes.
2031 Show the version number of @command{objcopy}.
2035 Verbose output: list all object files modified. In the case of
2036 archives, @samp{objcopy -V} lists all members of the archive.
2039 Show a summary of the options to @command{objcopy}.
2042 Display a list showing all architectures and object formats available.
2048 @c man begin SEEALSO objcopy
2049 ld(1), objdump(1), and the Info entries for @file{binutils}.
2056 @cindex object file information
2059 @c man title objdump display information from object files.
2062 @c man begin SYNOPSIS objdump
2063 objdump [@option{-a}|@option{--archive-headers}]
2064 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2065 [@option{-C}|@option{--demangle}[=@var{style}] ]
2066 [@option{-d}|@option{--disassemble}]
2067 [@option{-D}|@option{--disassemble-all}]
2068 [@option{-z}|@option{--disassemble-zeroes}]
2069 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2070 [@option{-f}|@option{--file-headers}]
2071 [@option{-F}|@option{--file-offsets}]
2072 [@option{--file-start-context}]
2073 [@option{-g}|@option{--debugging}]
2074 [@option{-e}|@option{--debugging-tags}]
2075 [@option{-h}|@option{--section-headers}|@option{--headers}]
2076 [@option{-i}|@option{--info}]
2077 [@option{-j} @var{section}|@option{--section=}@var{section}]
2078 [@option{-l}|@option{--line-numbers}]
2079 [@option{-S}|@option{--source}]
2080 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2081 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2082 [@option{-p}|@option{--private-headers}]
2083 [@option{-P} @var{options}|@option{--private=}@var{options}]
2084 [@option{-r}|@option{--reloc}]
2085 [@option{-R}|@option{--dynamic-reloc}]
2086 [@option{-s}|@option{--full-contents}]
2087 [@option{-W[lLiaprmfFsoRtUuTgAckK]}|
2088 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]]
2089 [@option{-G}|@option{--stabs}]
2090 [@option{-t}|@option{--syms}]
2091 [@option{-T}|@option{--dynamic-syms}]
2092 [@option{-x}|@option{--all-headers}]
2093 [@option{-w}|@option{--wide}]
2094 [@option{--start-address=}@var{address}]
2095 [@option{--stop-address=}@var{address}]
2096 [@option{--prefix-addresses}]
2097 [@option{--[no-]show-raw-insn}]
2098 [@option{--adjust-vma=}@var{offset}]
2099 [@option{--dwarf-depth=@var{n}}]
2100 [@option{--dwarf-start=@var{n}}]
2101 [@option{--special-syms}]
2102 [@option{--prefix=}@var{prefix}]
2103 [@option{--prefix-strip=}@var{level}]
2104 [@option{--insn-width=}@var{width}]
2105 [@option{-V}|@option{--version}]
2106 [@option{-H}|@option{--help}]
2107 @var{objfile}@dots{}
2111 @c man begin DESCRIPTION objdump
2113 @command{objdump} displays information about one or more object files.
2114 The options control what particular information to display. This
2115 information is mostly useful to programmers who are working on the
2116 compilation tools, as opposed to programmers who just want their
2117 program to compile and work.
2119 @var{objfile}@dots{} are the object files to be examined. When you
2120 specify archives, @command{objdump} shows information on each of the member
2125 @c man begin OPTIONS objdump
2127 The long and short forms of options, shown here as alternatives, are
2128 equivalent. At least one option from the list
2129 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2133 @itemx --archive-header
2134 @cindex archive headers
2135 If any of the @var{objfile} files are archives, display the archive
2136 header information (in a format similar to @samp{ls -l}). Besides the
2137 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2138 the object file format of each archive member.
2140 @item --adjust-vma=@var{offset}
2141 @cindex section addresses in objdump
2142 @cindex VMA in objdump
2143 When dumping information, first add @var{offset} to all the section
2144 addresses. This is useful if the section addresses do not correspond to
2145 the symbol table, which can happen when putting sections at particular
2146 addresses when using a format which can not represent section addresses,
2149 @item -b @var{bfdname}
2150 @itemx --target=@var{bfdname}
2151 @cindex object code format
2152 Specify that the object-code format for the object files is
2153 @var{bfdname}. This option may not be necessary; @var{objdump} can
2154 automatically recognize many formats.
2158 objdump -b oasys -m vax -h fu.o
2161 displays summary information from the section headers (@option{-h}) of
2162 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2163 file in the format produced by Oasys compilers. You can list the
2164 formats available with the @option{-i} option.
2165 @xref{Target Selection}, for more information.
2168 @itemx --demangle[=@var{style}]
2169 @cindex demangling in objdump
2170 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2171 Besides removing any initial underscore prepended by the system, this
2172 makes C++ function names readable. Different compilers have different
2173 mangling styles. The optional demangling style argument can be used to
2174 choose an appropriate demangling style for your compiler. @xref{c++filt},
2175 for more information on demangling.
2179 Display debugging information. This attempts to parse STABS
2180 debugging format information stored in the file and print it out using
2181 a C like syntax. If no STABS debuging was found this option
2182 falls back on the @option{-W} option to print any DWARF information in
2186 @itemx --debugging-tags
2187 Like @option{-g}, but the information is generated in a format compatible
2191 @itemx --disassemble
2192 @cindex disassembling object code
2193 @cindex machine instructions
2194 Display the assembler mnemonics for the machine instructions from
2195 @var{objfile}. This option only disassembles those sections which are
2196 expected to contain instructions.
2199 @itemx --disassemble-all
2200 Like @option{-d}, but disassemble the contents of all sections, not just
2201 those expected to contain instructions.
2203 This option also has a subtle effect on the disassembly of
2204 instructions in code sections. When option @option{-d} is in effect
2205 objdump will assume that any symbols present in a code section occur
2206 on the boundary between instructions and it will refuse to disassemble
2207 across such a boundary. When option @option{-D} is in effect however
2208 this assumption is supressed. This means that it is possible for the
2209 output of @option{-d} and @option{-D} to differ if, for example, data
2210 is stored in code sections.
2212 If the target is an ARM architecture this switch also has the effect
2213 of forcing the disassembler to decode pieces of data found in code
2214 sections as if they were instructions.
2216 @item --prefix-addresses
2217 When disassembling, print the complete address on each line. This is
2218 the older disassembly format.
2222 @itemx --endian=@{big|little@}
2224 @cindex disassembly endianness
2225 Specify the endianness of the object files. This only affects
2226 disassembly. This can be useful when disassembling a file format which
2227 does not describe endianness information, such as S-records.
2230 @itemx --file-headers
2231 @cindex object file header
2232 Display summary information from the overall header of
2233 each of the @var{objfile} files.
2236 @itemx --file-offsets
2237 @cindex object file offsets
2238 When disassembling sections, whenever a symbol is displayed, also
2239 display the file offset of the region of data that is about to be
2240 dumped. If zeroes are being skipped, then when disassembly resumes,
2241 tell the user how many zeroes were skipped and the file offset of the
2242 location from where the disassembly resumes. When dumping sections,
2243 display the file offset of the location from where the dump starts.
2245 @item --file-start-context
2246 @cindex source code context
2247 Specify that when displaying interlisted source code/disassembly
2248 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2249 context to the start of the file.
2252 @itemx --section-headers
2254 @cindex section headers
2255 Display summary information from the section headers of the
2258 File segments may be relocated to nonstandard addresses, for example by
2259 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2260 @command{ld}. However, some object file formats, such as a.out, do not
2261 store the starting address of the file segments. In those situations,
2262 although @command{ld} relocates the sections correctly, using @samp{objdump
2263 -h} to list the file section headers cannot show the correct addresses.
2264 Instead, it shows the usual addresses, which are implicit for the
2267 Note, in some cases it is possible for a section to have both the
2268 READONLY and the NOREAD attributes set. In such cases the NOREAD
2269 attribute takes precedence, but @command{objdump} will report both
2270 since the exact setting of the flag bits might be important.
2274 Print a summary of the options to @command{objdump} and exit.
2278 @cindex architectures available
2279 @cindex object formats available
2280 Display a list showing all architectures and object formats available
2281 for specification with @option{-b} or @option{-m}.
2284 @itemx --section=@var{name}
2285 @cindex section information
2286 Display information only for section @var{name}.
2289 @itemx --line-numbers
2290 @cindex source filenames for object files
2291 Label the display (using debugging information) with the filename and
2292 source line numbers corresponding to the object code or relocs shown.
2293 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2295 @item -m @var{machine}
2296 @itemx --architecture=@var{machine}
2297 @cindex architecture
2298 @cindex disassembly architecture
2299 Specify the architecture to use when disassembling object files. This
2300 can be useful when disassembling object files which do not describe
2301 architecture information, such as S-records. You can list the available
2302 architectures with the @option{-i} option.
2304 If the target is an ARM architecture then this switch has an
2305 additional effect. It restricts the disassembly to only those
2306 instructions supported by the architecture specified by @var{machine}.
2307 If it is necessary to use this switch because the input file does not
2308 contain any architecture information, but it is also desired to
2309 disassemble all the instructions use @option{-marm}.
2311 @item -M @var{options}
2312 @itemx --disassembler-options=@var{options}
2313 Pass target specific information to the disassembler. Only supported on
2314 some targets. If it is necessary to specify more than one
2315 disassembler option then multiple @option{-M} options can be used or
2316 can be placed together into a comma separated list.
2318 For ARC, @option{dsp} controls the printing of DSP instructions,
2319 @option{spfp} selects the printing of FPX single precision FP
2320 instructions, @option{dpfp} selects the printing of FPX double
2321 precision FP instructions, @option{quarkse_em} selects the printing of
2322 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2323 of double precision assist instructions, @option{fpus} selects the
2324 printing of FPU single precision FP instructions, while @option{fpud}
2325 selects the printing of FPU double precision FP instructions.
2326 Additionally, one can choose to have all the immediates printed in
2327 hexadecimal using @option{hex}. By default, the short immediates are
2328 printed using the decimal representation, while the long immediate
2329 values are printed as hexadecimal.
2331 @option{cpu=...} allows to enforce a particular ISA when disassembling
2332 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2333 This might be useful to select ARC EM or HS ISA, because architecture is same
2334 for those and disassembler relies on private ELF header data to decide if code
2335 is for EM or HS. This option might be specified multiple times - only the
2336 latest value will be used. Valid values are same as for the assembler
2337 @option{-mcpu=...} option.
2339 If the target is an ARM architecture then this switch can be used to
2340 select which register name set is used during disassembler. Specifying
2341 @option{-M reg-names-std} (the default) will select the register names as
2342 used in ARM's instruction set documentation, but with register 13 called
2343 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2344 @option{-M reg-names-apcs} will select the name set used by the ARM
2345 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2346 just use @samp{r} followed by the register number.
2348 There are also two variants on the APCS register naming scheme enabled
2349 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2350 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2351 with the normal register names or the special register names).
2353 This option can also be used for ARM architectures to force the
2354 disassembler to interpret all instructions as Thumb instructions by
2355 using the switch @option{--disassembler-options=force-thumb}. This can be
2356 useful when attempting to disassemble thumb code produced by other
2359 For AArch64 targets this switch can be used to set whether instructions are
2360 disassembled as the most general instruction using the @option{-M no-aliases}
2361 option or whether instruction notes should be generated as comments in the
2362 disasssembly using @option{-M notes}.
2364 For the x86, some of the options duplicate functions of the @option{-m}
2365 switch, but allow finer grained control. Multiple selections from the
2366 following may be specified as a comma separated string.
2371 Select disassembly for the given architecture.
2375 Select between intel syntax mode and AT&T syntax mode.
2379 Select between AMD64 ISA and Intel64 ISA.
2381 @item intel-mnemonic
2383 Select between intel mnemonic mode and AT&T mnemonic mode.
2384 Note: @code{intel-mnemonic} implies @code{intel} and
2385 @code{att-mnemonic} implies @code{att}.
2392 Specify the default address size and operand size. These four options
2393 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2394 appear later in the option string.
2397 When in AT&T mode, instructs the disassembler to print a mnemonic
2398 suffix even when the suffix could be inferred by the operands.
2401 For PowerPC, the @option{-M} argument @option{raw} selects
2402 disasssembly of hardware insns rather than aliases. For example, you
2403 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2404 rather than @code{li}. All of the @option{-m} arguments for
2405 @command{gas} that select a CPU are supported. These are:
2406 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2407 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2408 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2409 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2410 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2411 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2412 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2413 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2414 @option{power8}, @option{power9}, @option{ppc}, @option{ppc32},
2415 @option{ppc64}, @option{ppc64bridge}, @option{ppcps}, @option{pwr},
2416 @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2417 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2418 @option{pwrx}, @option{titan}, and @option{vle}.
2419 @option{32} and @option{64} modify the default or a prior CPU
2420 selection, disabling and enabling 64-bit insns respectively. In
2421 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2422 and @option{spe} add capabilities to a previous @emph{or later} CPU
2423 selection. @option{any} will disassemble any opcode known to
2424 binutils, but in cases where an opcode has two different meanings or
2425 different arguments, you may not see the disassembly you expect.
2426 If you disassemble without giving a CPU selection, a default will be
2427 chosen from information gleaned by BFD from the object files headers,
2428 but the result again may not be as you expect.
2430 For MIPS, this option controls the printing of instruction mnemonic
2431 names and register names in disassembled instructions. Multiple
2432 selections from the following may be specified as a comma separated
2433 string, and invalid options are ignored:
2437 Print the 'raw' instruction mnemonic instead of some pseudo
2438 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2439 'sll' instead of 'nop', etc.
2442 Disassemble MSA instructions.
2445 Disassemble the virtualization ASE instructions.
2448 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2450 @item gpr-names=@var{ABI}
2451 Print GPR (general-purpose register) names as appropriate
2452 for the specified ABI. By default, GPR names are selected according to
2453 the ABI of the binary being disassembled.
2455 @item fpr-names=@var{ABI}
2456 Print FPR (floating-point register) names as
2457 appropriate for the specified ABI. By default, FPR numbers are printed
2460 @item cp0-names=@var{ARCH}
2461 Print CP0 (system control coprocessor; coprocessor 0) register names
2462 as appropriate for the CPU or architecture specified by
2463 @var{ARCH}. By default, CP0 register names are selected according to
2464 the architecture and CPU of the binary being disassembled.
2466 @item hwr-names=@var{ARCH}
2467 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2468 as appropriate for the CPU or architecture specified by
2469 @var{ARCH}. By default, HWR names are selected according to
2470 the architecture and CPU of the binary being disassembled.
2472 @item reg-names=@var{ABI}
2473 Print GPR and FPR names as appropriate for the selected ABI.
2475 @item reg-names=@var{ARCH}
2476 Print CPU-specific register names (CP0 register and HWR names)
2477 as appropriate for the selected CPU or architecture.
2480 For any of the options listed above, @var{ABI} or
2481 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2482 rather than names, for the selected types of registers.
2483 You can list the available values of @var{ABI} and @var{ARCH} using
2484 the @option{--help} option.
2486 For VAX, you can specify function entry addresses with @option{-M
2487 entry:0xf00ba}. You can use this multiple times to properly
2488 disassemble VAX binary files that don't contain symbol tables (like
2489 ROM dumps). In these cases, the function entry mask would otherwise
2490 be decoded as VAX instructions, which would probably lead the rest
2491 of the function being wrongly disassembled.
2494 @itemx --private-headers
2495 Print information that is specific to the object file format. The exact
2496 information printed depends upon the object file format. For some
2497 object file formats, no additional information is printed.
2499 @item -P @var{options}
2500 @itemx --private=@var{options}
2501 Print information that is specific to the object file format. The
2502 argument @var{options} is a comma separated list that depends on the
2503 format (the lists of options is displayed with the help).
2505 For XCOFF, the available options are:
2521 Not all object formats support this option. In particular the ELF
2522 format does not use it.
2526 @cindex relocation entries, in object file
2527 Print the relocation entries of the file. If used with @option{-d} or
2528 @option{-D}, the relocations are printed interspersed with the
2532 @itemx --dynamic-reloc
2533 @cindex dynamic relocation entries, in object file
2534 Print the dynamic relocation entries of the file. This is only
2535 meaningful for dynamic objects, such as certain types of shared
2536 libraries. As for @option{-r}, if used with @option{-d} or
2537 @option{-D}, the relocations are printed interspersed with the
2541 @itemx --full-contents
2542 @cindex sections, full contents
2543 @cindex object file sections
2544 Display the full contents of any sections requested. By default all
2545 non-empty sections are displayed.
2549 @cindex source disassembly
2550 @cindex disassembly, with source
2551 Display source code intermixed with disassembly, if possible. Implies
2554 @item --prefix=@var{prefix}
2555 @cindex Add prefix to absolute paths
2556 Specify @var{prefix} to add to the absolute paths when used with
2559 @item --prefix-strip=@var{level}
2560 @cindex Strip absolute paths
2561 Indicate how many initial directory names to strip off the hardwired
2562 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2564 @item --show-raw-insn
2565 When disassembling instructions, print the instruction in hex as well as
2566 in symbolic form. This is the default except when
2567 @option{--prefix-addresses} is used.
2569 @item --no-show-raw-insn
2570 When disassembling instructions, do not print the instruction bytes.
2571 This is the default when @option{--prefix-addresses} is used.
2573 @item --insn-width=@var{width}
2574 @cindex Instruction width
2575 Display @var{width} bytes on a single line when disassembling
2578 @item -W[lLiaprmfFsoRtUuTgAckK]
2579 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
2580 @include debug.options.texi
2583 Enable additional checks for consistency of Dwarf information.
2589 @cindex debug symbols
2590 @cindex ELF object file format
2591 Display the full contents of any sections requested. Display the
2592 contents of the .stab and .stab.index and .stab.excl sections from an
2593 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2594 @code{.stab} debugging symbol-table entries are carried in an ELF
2595 section. In most other file formats, debugging symbol-table entries are
2596 interleaved with linkage symbols, and are visible in the @option{--syms}
2599 @item --start-address=@var{address}
2600 @cindex start-address
2601 Start displaying data at the specified address. This affects the output
2602 of the @option{-d}, @option{-r} and @option{-s} options.
2604 @item --stop-address=@var{address}
2605 @cindex stop-address
2606 Stop displaying data at the specified address. This affects the output
2607 of the @option{-d}, @option{-r} and @option{-s} options.
2611 @cindex symbol table entries, printing
2612 Print the symbol table entries of the file.
2613 This is similar to the information provided by the @samp{nm} program,
2614 although the display format is different. The format of the output
2615 depends upon the format of the file being dumped, but there are two main
2616 types. One looks like this:
2619 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2620 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2623 where the number inside the square brackets is the number of the entry
2624 in the symbol table, the @var{sec} number is the section number, the
2625 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2626 symbol's type, the @var{scl} number is the symbol's storage class and
2627 the @var{nx} value is the number of auxilary entries associated with
2628 the symbol. The last two fields are the symbol's value and its name.
2630 The other common output format, usually seen with ELF based files,
2634 00000000 l d .bss 00000000 .bss
2635 00000000 g .text 00000000 fred
2638 Here the first number is the symbol's value (sometimes refered to as
2639 its address). The next field is actually a set of characters and
2640 spaces indicating the flag bits that are set on the symbol. These
2641 characters are described below. Next is the section with which the
2642 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2643 not connected with any section), or @emph{*UND*} if the section is
2644 referenced in the file being dumped, but not defined there.
2646 After the section name comes another field, a number, which for common
2647 symbols is the alignment and for other symbol is the size. Finally
2648 the symbol's name is displayed.
2650 The flag characters are divided into 7 groups as follows:
2656 The symbol is a local (l), global (g), unique global (u), neither
2657 global nor local (a space) or both global and local (!). A
2658 symbol can be neither local or global for a variety of reasons, e.g.,
2659 because it is used for debugging, but it is probably an indication of
2660 a bug if it is ever both local and global. Unique global symbols are
2661 a GNU extension to the standard set of ELF symbol bindings. For such
2662 a symbol the dynamic linker will make sure that in the entire process
2663 there is just one symbol with this name and type in use.
2666 The symbol is weak (w) or strong (a space).
2669 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2672 The symbol is a warning (W) or a normal symbol (a space). A warning
2673 symbol's name is a message to be displayed if the symbol following the
2674 warning symbol is ever referenced.
2678 The symbol is an indirect reference to another symbol (I), a function
2679 to be evaluated during reloc processing (i) or a normal symbol (a
2684 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2685 normal symbol (a space).
2690 The symbol is the name of a function (F) or a file (f) or an object
2691 (O) or just a normal symbol (a space).
2695 @itemx --dynamic-syms
2696 @cindex dynamic symbol table entries, printing
2697 Print the dynamic symbol table entries of the file. This is only
2698 meaningful for dynamic objects, such as certain types of shared
2699 libraries. This is similar to the information provided by the @samp{nm}
2700 program when given the @option{-D} (@option{--dynamic}) option.
2702 The output format is similar to that produced by the @option{--syms}
2703 option, except that an extra field is inserted before the symbol's
2704 name, giving the version information associated with the symbol.
2705 If the version is the default version to be used when resolving
2706 unversioned references to the symbol then it's displayed as is,
2707 otherwise it's put into parentheses.
2709 @item --special-syms
2710 When displaying symbols include those which the target considers to be
2711 special in some way and which would not normally be of interest to the
2716 Print the version number of @command{objdump} and exit.
2719 @itemx --all-headers
2720 @cindex all header information, object file
2721 @cindex header information, all
2722 Display all available header information, including the symbol table and
2723 relocation entries. Using @option{-x} is equivalent to specifying all of
2724 @option{-a -f -h -p -r -t}.
2728 @cindex wide output, printing
2729 Format some lines for output devices that have more than 80 columns.
2730 Also do not truncate symbol names when they are displayed.
2733 @itemx --disassemble-zeroes
2734 Normally the disassembly output will skip blocks of zeroes. This
2735 option directs the disassembler to disassemble those blocks, just like
2742 @c man begin SEEALSO objdump
2743 nm(1), readelf(1), and the Info entries for @file{binutils}.
2751 @cindex archive contents
2752 @cindex symbol index
2754 @c man title ranlib generate index to archive.
2757 @c man begin SYNOPSIS ranlib
2758 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2762 @c man begin DESCRIPTION ranlib
2764 @command{ranlib} generates an index to the contents of an archive and
2765 stores it in the archive. The index lists each symbol defined by a
2766 member of an archive that is a relocatable object file.
2768 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2770 An archive with such an index speeds up linking to the library and
2771 allows routines in the library to call each other without regard to
2772 their placement in the archive.
2774 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2775 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2780 @c man begin OPTIONS ranlib
2786 Show usage information for @command{ranlib}.
2791 Show the version number of @command{ranlib}.
2794 @cindex deterministic archives
2795 @kindex --enable-deterministic-archives
2796 Operate in @emph{deterministic} mode. The symbol map archive member's
2797 header will show zero for the UID, GID, and timestamp. When this
2798 option is used, multiple runs will produce identical output files.
2800 If @file{binutils} was configured with
2801 @option{--enable-deterministic-archives}, then this mode is on by
2802 default. It can be disabled with the @samp{-U} option, described
2806 Update the timestamp of the symbol map of an archive.
2809 @cindex deterministic archives
2810 @kindex --enable-deterministic-archives
2811 Do @emph{not} operate in @emph{deterministic} mode. This is the
2812 inverse of the @samp{-D} option, above: the archive index will get
2813 actual UID, GID, timestamp, and file mode values.
2815 If @file{binutils} was configured @emph{without}
2816 @option{--enable-deterministic-archives}, then this mode is on by
2824 @c man begin SEEALSO ranlib
2825 ar(1), nm(1), and the Info entries for @file{binutils}.
2833 @cindex section sizes
2835 @c man title size list section sizes and total size.
2838 @c man begin SYNOPSIS size
2839 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2841 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2843 [@option{-t}|@option{--totals}]
2844 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2845 [@var{objfile}@dots{}]
2849 @c man begin DESCRIPTION size
2851 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2852 size---for each of the object or archive files @var{objfile} in its
2853 argument list. By default, one line of output is generated for each
2854 object file or each module in an archive.
2856 @var{objfile}@dots{} are the object files to be examined.
2857 If none are specified, the file @code{a.out} will be used.
2861 @c man begin OPTIONS size
2863 The command-line options have the following meanings:
2868 @itemx --format=@var{compatibility}
2869 @cindex @command{size} display format
2870 Using one of these options, you can choose whether the output from @sc{gnu}
2871 @command{size} resembles output from System V @command{size} (using @option{-A},
2872 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2873 @option{--format=berkeley}). The default is the one-line format similar to
2875 @c Bonus for doc-source readers: you can also say --format=strange (or
2876 @c anything else that starts with 's') for sysv, and --format=boring (or
2877 @c anything else that starts with 'b') for Berkeley.
2879 Here is an example of the Berkeley (default) format of output from
2882 $ size --format=Berkeley ranlib size
2883 text data bss dec hex filename
2884 294880 81920 11592 388392 5ed28 ranlib
2885 294880 81920 11888 388688 5ee50 size
2889 This is the same data, but displayed closer to System V conventions:
2892 $ size --format=SysV ranlib size
2910 Show a summary of acceptable arguments and options.
2915 @itemx --radix=@var{number}
2916 @cindex @command{size} number format
2917 @cindex radix for section sizes
2918 Using one of these options, you can control whether the size of each
2919 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2920 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2921 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2922 values (8, 10, 16) are supported. The total size is always given in two
2923 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2924 octal and hexadecimal if you're using @option{-o}.
2927 Print total size of common symbols in each file. When using Berkeley
2928 format these are included in the bss size.
2932 Show totals of all objects listed (Berkeley format listing mode only).
2934 @item --target=@var{bfdname}
2935 @cindex object code format
2936 Specify that the object-code format for @var{objfile} is
2937 @var{bfdname}. This option may not be necessary; @command{size} can
2938 automatically recognize many formats.
2939 @xref{Target Selection}, for more information.
2943 Display the version number of @command{size}.
2949 @c man begin SEEALSO size
2950 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2957 @cindex listings strings
2958 @cindex printing strings
2959 @cindex strings, printing
2961 @c man title strings print the strings of printable characters in files.
2964 @c man begin SYNOPSIS strings
2965 strings [@option{-afovV}] [@option{-}@var{min-len}]
2966 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2967 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2968 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2969 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2970 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2971 [@option{-w}] [@option{--include-all-whitespace}]
2972 [@option{-s}] [@option{--output-separator}@var{sep_string}]
2973 [@option{--help}] [@option{--version}] @var{file}@dots{}
2977 @c man begin DESCRIPTION strings
2979 For each @var{file} given, @sc{gnu} @command{strings} prints the
2980 printable character sequences that are at least 4 characters long (or
2981 the number given with the options below) and are followed by an
2982 unprintable character.
2984 Depending upon how the strings program was configured it will default
2985 to either displaying all the printable sequences that it can find in
2986 each file, or only those sequences that are in loadable, initialized
2987 data sections. If the file type in unrecognizable, or if strings is
2988 reading from stdin then it will always display all of the printable
2989 sequences that it can find.
2991 For backwards compatibility any file that occurs after a command-line
2992 option of just @option{-} will also be scanned in full, regardless of
2993 the presence of any @option{-d} option.
2995 @command{strings} is mainly useful for determining the contents of
3000 @c man begin OPTIONS strings
3006 Scan the whole file, regardless of what sections it contains or
3007 whether those sections are loaded or initialized. Normally this is
3008 the default behaviour, but strings can be configured so that the
3009 @option{-d} is the default instead.
3011 The @option{-} option is position dependent and forces strings to
3012 perform full scans of any file that is mentioned after the @option{-}
3013 on the command line, even if the @option{-d} option has been
3018 Only print strings from initialized, loaded data sections in the
3019 file. This may reduce the amount of garbage in the output, but it
3020 also exposes the strings program to any security flaws that may be
3021 present in the BFD library used to scan and load sections. Strings
3022 can be configured so that this option is the default behaviour. In
3023 such cases the @option{-a} option can be used to avoid using the BFD
3024 library and instead just print all of the strings found in the file.
3027 @itemx --print-file-name
3028 Print the name of the file before each string.
3031 Print a summary of the program usage on the standard output and exit.
3033 @item -@var{min-len}
3034 @itemx -n @var{min-len}
3035 @itemx --bytes=@var{min-len}
3036 Print sequences of characters that are at least @var{min-len} characters
3037 long, instead of the default 4.
3040 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3041 act like @samp{-t d} instead. Since we can not be compatible with both
3042 ways, we simply chose one.
3044 @item -t @var{radix}
3045 @itemx --radix=@var{radix}
3046 Print the offset within the file before each string. The single
3047 character argument specifies the radix of the offset---@samp{o} for
3048 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3050 @item -e @var{encoding}
3051 @itemx --encoding=@var{encoding}
3052 Select the character encoding of the strings that are to be found.
3053 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3054 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3055 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3056 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3057 littleendian. Useful for finding wide character strings. (@samp{l}
3058 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3060 @item -T @var{bfdname}
3061 @itemx --target=@var{bfdname}
3062 @cindex object code format
3063 Specify an object code format other than your system's default format.
3064 @xref{Target Selection}, for more information.
3069 Print the program version number on the standard output and exit.
3072 @itemx --include-all-whitespace
3073 By default tab and space characters are included in the strings that
3074 are displayed, but other whitespace characters, such a newlines and
3075 carriage returns, are not. The @option{-w} option changes this so
3076 that all whitespace characters are considered to be part of a string.
3079 @itemx --output-separator
3080 By default, output strings are delimited by a new-line. This option
3081 allows you to supply any string to be used as the output record
3082 separator. Useful with --include-all-whitespace where strings
3083 may contain new-lines internally.
3089 @c man begin SEEALSO strings
3090 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3091 and the Info entries for @file{binutils}.
3099 @cindex removing symbols
3100 @cindex discarding symbols
3101 @cindex symbols, discarding
3103 @c man title strip Discard symbols from object files.
3106 @c man begin SYNOPSIS strip
3107 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3108 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3109 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3110 [@option{-s}|@option{--strip-all}]
3111 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3112 [@option{--strip-dwo}]
3113 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3114 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3115 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3116 [@option{-w}|@option{--wildcard}]
3117 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3118 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3119 [@option{--remove-relocations=}@var{sectionpattern}]
3120 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3121 [@option{-D}|@option{--enable-deterministic-archives}]
3122 [@option{-U}|@option{--disable-deterministic-archives}]
3123 [@option{--keep-file-symbols}]
3124 [@option{--only-keep-debug}]
3125 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3126 [@option{--help}] [@option{--info}]
3127 @var{objfile}@dots{}
3131 @c man begin DESCRIPTION strip
3133 @sc{gnu} @command{strip} discards all symbols from object files
3134 @var{objfile}. The list of object files may include archives.
3135 At least one object file must be given.
3137 @command{strip} modifies the files named in its argument,
3138 rather than writing modified copies under different names.
3142 @c man begin OPTIONS strip
3145 @item -F @var{bfdname}
3146 @itemx --target=@var{bfdname}
3147 Treat the original @var{objfile} as a file with the object
3148 code format @var{bfdname}, and rewrite it in the same format.
3149 @xref{Target Selection}, for more information.
3152 Show a summary of the options to @command{strip} and exit.
3155 Display a list showing all architectures and object formats available.
3157 @item -I @var{bfdname}
3158 @itemx --input-target=@var{bfdname}
3159 Treat the original @var{objfile} as a file with the object
3160 code format @var{bfdname}.
3161 @xref{Target Selection}, for more information.
3163 @item -O @var{bfdname}
3164 @itemx --output-target=@var{bfdname}
3165 Replace @var{objfile} with a file in the output format @var{bfdname}.
3166 @xref{Target Selection}, for more information.
3168 @item -R @var{sectionname}
3169 @itemx --remove-section=@var{sectionname}
3170 Remove any section named @var{sectionname} from the output file, in
3171 addition to whatever sections would otherwise be removed. This
3172 option may be given more than once. Note that using this option
3173 inappropriately may make the output file unusable. The wildcard
3174 character @samp{*} may be given at the end of @var{sectionname}. If
3175 so, then any section starting with @var{sectionname} will be removed.
3177 If the first character of @var{sectionpattern} is the exclamation
3178 point (!) then matching sections will not be removed even if an
3179 earlier use of @option{--remove-section} on the same command line
3180 would otherwise remove it. For example:
3183 --remove-section=.text.* --remove-section=!.text.foo
3186 will remove all sections matching the pattern '.text.*', but will not
3187 remove the section '.text.foo'.
3189 @item --remove-relocations=@var{sectionpattern}
3190 Remove relocations from the output file for any section matching
3191 @var{sectionpattern}. This option may be given more than once. Note
3192 that using this option inappropriately may make the output file
3193 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3197 --remove-relocations=.text.*
3200 will remove the relocations for all sections matching the patter
3203 If the first character of @var{sectionpattern} is the exclamation
3204 point (!) then matching sections will not have their relocation
3205 removed even if an earlier use of @option{--remove-relocations} on the
3206 same command line would otherwise cause the relocations to be removed.
3210 --remove-relocations=.text.* --remove-relocations=!.text.foo
3213 will remove all relocations for sections matching the pattern
3214 '.text.*', but will not remove relocations for the section
3224 @itemx --strip-debug
3225 Remove debugging symbols only.
3228 Remove the contents of all DWARF .dwo sections, leaving the
3229 remaining debugging sections and all symbols intact.
3230 See the description of this option in the @command{objcopy} section
3231 for more information.
3233 @item --strip-unneeded
3234 Remove all symbols that are not needed for relocation processing.
3236 @item -K @var{symbolname}
3237 @itemx --keep-symbol=@var{symbolname}
3238 When stripping symbols, keep symbol @var{symbolname} even if it would
3239 normally be stripped. This option may be given more than once.
3242 @itemx --merge-notes
3243 @itemx --no-merge-notes
3244 For ELF files, attempt (or do not attempt) to reduce the size of any
3245 SHT_NOTE type sections by removing duplicate notes. The default is to
3246 attempt this reduction.
3248 @item -N @var{symbolname}
3249 @itemx --strip-symbol=@var{symbolname}
3250 Remove symbol @var{symbolname} from the source file. This option may be
3251 given more than once, and may be combined with strip options other than
3255 Put the stripped output in @var{file}, rather than replacing the
3256 existing file. When this argument is used, only one @var{objfile}
3257 argument may be specified.
3260 @itemx --preserve-dates
3261 Preserve the access and modification dates of the file.
3264 @itemx --enable-deterministic-archives
3265 @cindex deterministic archives
3266 @kindex --enable-deterministic-archives
3267 Operate in @emph{deterministic} mode. When copying archive members
3268 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3269 and use consistent file modes for all files.
3271 If @file{binutils} was configured with
3272 @option{--enable-deterministic-archives}, then this mode is on by default.
3273 It can be disabled with the @samp{-U} option, below.
3276 @itemx --disable-deterministic-archives
3277 @cindex deterministic archives
3278 @kindex --enable-deterministic-archives
3279 Do @emph{not} operate in @emph{deterministic} mode. This is the
3280 inverse of the @option{-D} option, above: when copying archive members
3281 and writing the archive index, use their actual UID, GID, timestamp,
3282 and file mode values.
3284 This is the default unless @file{binutils} was configured with
3285 @option{--enable-deterministic-archives}.
3289 Permit regular expressions in @var{symbolname}s used in other command
3290 line options. The question mark (?), asterisk (*), backslash (\) and
3291 square brackets ([]) operators can be used anywhere in the symbol
3292 name. If the first character of the symbol name is the exclamation
3293 point (!) then the sense of the switch is reversed for that symbol.
3300 would cause strip to only keep symbols that start with the letters
3301 ``fo'', but to discard the symbol ``foo''.
3304 @itemx --discard-all
3305 Remove non-global symbols.
3308 @itemx --discard-locals
3309 Remove compiler-generated local symbols.
3310 (These usually start with @samp{L} or @samp{.}.)
3312 @item --keep-file-symbols
3313 When stripping a file, perhaps with @option{--strip-debug} or
3314 @option{--strip-unneeded}, retain any symbols specifying source file names,
3315 which would otherwise get stripped.
3317 @item --only-keep-debug
3318 Strip a file, emptying the contents of any sections that would not be
3319 stripped by @option{--strip-debug} and leaving the debugging sections
3320 intact. In ELF files, this preserves all the note sections in the
3323 Note - the section headers of the stripped sections are preserved,
3324 including their sizes, but the contents of the section are discarded.
3325 The section headers are preserved so that other tools can match up the
3326 debuginfo file with the real executable, even if that executable has
3327 been relocated to a different address space.
3329 The intention is that this option will be used in conjunction with
3330 @option{--add-gnu-debuglink} to create a two part executable. One a
3331 stripped binary which will occupy less space in RAM and in a
3332 distribution and the second a debugging information file which is only
3333 needed if debugging abilities are required. The suggested procedure
3334 to create these files is as follows:
3337 @item Link the executable as normal. Assuming that it is called
3339 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3340 create a file containing the debugging info.
3341 @item Run @code{objcopy --strip-debug foo} to create a
3342 stripped executable.
3343 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3344 to add a link to the debugging info into the stripped executable.
3347 Note---the choice of @code{.dbg} as an extension for the debug info
3348 file is arbitrary. Also the @code{--only-keep-debug} step is
3349 optional. You could instead do this:
3352 @item Link the executable as normal.
3353 @item Copy @code{foo} to @code{foo.full}
3354 @item Run @code{strip --strip-debug foo}
3355 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3358 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3359 full executable. It does not have to be a file created by the
3360 @option{--only-keep-debug} switch.
3362 Note---this switch is only intended for use on fully linked files. It
3363 does not make sense to use it on object files where the debugging
3364 information may be incomplete. Besides the gnu_debuglink feature
3365 currently only supports the presence of one filename containing
3366 debugging information, not multiple filenames on a one-per-object-file
3371 Show the version number for @command{strip}.
3375 Verbose output: list all object files modified. In the case of
3376 archives, @samp{strip -v} lists all members of the archive.
3382 @c man begin SEEALSO strip
3383 the Info entries for @file{binutils}.
3387 @node c++filt, addr2line, strip, Top
3391 @cindex demangling C++ symbols
3393 @c man title cxxfilt Demangle C++ and Java symbols.
3396 @c man begin SYNOPSIS cxxfilt
3397 c++filt [@option{-_}|@option{--strip-underscore}]
3398 [@option{-n}|@option{--no-strip-underscore}]
3399 [@option{-p}|@option{--no-params}]
3400 [@option{-t}|@option{--types}]
3401 [@option{-i}|@option{--no-verbose}]
3402 [@option{-s} @var{format}|@option{--format=}@var{format}]
3403 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3407 @c man begin DESCRIPTION cxxfilt
3410 The C++ and Java languages provide function overloading, which means
3411 that you can write many functions with the same name, providing that
3412 each function takes parameters of different types. In order to be
3413 able to distinguish these similarly named functions C++ and Java
3414 encode them into a low-level assembler name which uniquely identifies
3415 each different version. This process is known as @dfn{mangling}. The
3417 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3418 MS-DOS this program is named @command{CXXFILT}.}
3419 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3420 names into user-level names so that they can be read.
3422 Every alphanumeric word (consisting of letters, digits, underscores,
3423 dollars, or periods) seen in the input is a potential mangled name.
3424 If the name decodes into a C++ name, the C++ name replaces the
3425 low-level name in the output, otherwise the original word is output.
3426 In this way you can pass an entire assembler source file, containing
3427 mangled names, through @command{c++filt} and see the same source file
3428 containing demangled names.
3430 You can also use @command{c++filt} to decipher individual symbols by
3431 passing them on the command line:
3434 c++filt @var{symbol}
3437 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3438 names from the standard input instead. All the results are printed on
3439 the standard output. The difference between reading names from the
3440 command line versus reading names from the standard input is that
3441 command-line arguments are expected to be just mangled names and no
3442 checking is performed to separate them from surrounding text. Thus
3449 will work and demangle the name to ``f()'' whereas:
3455 will not work. (Note the extra comma at the end of the mangled
3456 name which makes it invalid). This command however will work:
3459 echo _Z1fv, | c++filt -n
3462 and will display ``f(),'', i.e., the demangled name followed by a
3463 trailing comma. This behaviour is because when the names are read
3464 from the standard input it is expected that they might be part of an
3465 assembler source file where there might be extra, extraneous
3466 characters trailing after a mangled name. For example:
3469 .type _Z1fv, @@function
3474 @c man begin OPTIONS cxxfilt
3478 @itemx --strip-underscore
3479 On some systems, both the C and C++ compilers put an underscore in front
3480 of every name. For example, the C name @code{foo} gets the low-level
3481 name @code{_foo}. This option removes the initial underscore. Whether
3482 @command{c++filt} removes the underscore by default is target dependent.
3485 @itemx --no-strip-underscore
3486 Do not remove the initial underscore.
3490 When demangling the name of a function, do not display the types of
3491 the function's parameters.
3495 Attempt to demangle types as well as function names. This is disabled
3496 by default since mangled types are normally only used internally in
3497 the compiler, and they can be confused with non-mangled names. For example,
3498 a function called ``a'' treated as a mangled type name would be
3499 demangled to ``signed char''.
3503 Do not include implementation details (if any) in the demangled
3506 @item -s @var{format}
3507 @itemx --format=@var{format}
3508 @command{c++filt} can decode various methods of mangling, used by
3509 different compilers. The argument to this option selects which
3514 Automatic selection based on executable (the default method)
3516 the one used by the @sc{gnu} C++ compiler (g++)
3518 the one used by the Lucid compiler (lcc)
3520 the one specified by the C++ Annotated Reference Manual
3522 the one used by the HP compiler (aCC)
3524 the one used by the EDG compiler
3526 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3528 the one used by the @sc{gnu} Java compiler (gcj)
3530 the one used by the @sc{gnu} Ada compiler (GNAT).
3534 Print a summary of the options to @command{c++filt} and exit.
3537 Print the version number of @command{c++filt} and exit.
3543 @c man begin SEEALSO cxxfilt
3544 the Info entries for @file{binutils}.
3549 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3550 user interface are subject to change in future releases. In particular,
3551 a command-line option may be required in the future to decode a name
3552 passed as an argument on the command line; in other words,
3555 c++filt @var{symbol}
3559 may in a future release become
3562 c++filt @var{option} @var{symbol}
3570 @cindex address to file name and line number
3572 @c man title addr2line convert addresses into file names and line numbers.
3575 @c man begin SYNOPSIS addr2line
3576 addr2line [@option{-a}|@option{--addresses}]
3577 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3578 [@option{-C}|@option{--demangle}[=@var{style}]]
3579 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3580 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3581 [@option{-i}|@option{--inlines}]
3582 [@option{-p}|@option{--pretty-print}]
3583 [@option{-j}|@option{--section=}@var{name}]
3584 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3589 @c man begin DESCRIPTION addr2line
3591 @command{addr2line} translates addresses into file names and line numbers.
3592 Given an address in an executable or an offset in a section of a relocatable
3593 object, it uses the debugging information to figure out which file name and
3594 line number are associated with it.
3596 The executable or relocatable object to use is specified with the @option{-e}
3597 option. The default is the file @file{a.out}. The section in the relocatable
3598 object to use is specified with the @option{-j} option.
3600 @command{addr2line} has two modes of operation.
3602 In the first, hexadecimal addresses are specified on the command line,
3603 and @command{addr2line} displays the file name and line number for each
3606 In the second, @command{addr2line} reads hexadecimal addresses from
3607 standard input, and prints the file name and line number for each
3608 address on standard output. In this mode, @command{addr2line} may be used
3609 in a pipe to convert dynamically chosen addresses.
3611 The format of the output is @samp{FILENAME:LINENO}. By default
3612 each input address generates one line of output.
3614 Two options can generate additional lines before each
3615 @samp{FILENAME:LINENO} line (in that order).
3617 If the @option{-a} option is used then a line with the input address
3620 If the @option{-f} option is used, then a line with the
3621 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3622 containing the address.
3624 One option can generate additional lines after the
3625 @samp{FILENAME:LINENO} line.
3627 If the @option{-i} option is used and the code at the given address is
3628 present there because of inlining by the compiler then additional
3629 lines are displayed afterwards. One or two extra lines (if the
3630 @option{-f} option is used) are displayed for each inlined function.
3632 Alternatively if the @option{-p} option is used then each input
3633 address generates a single, long, output line containing the address,
3634 the function name, the file name and the line number. If the
3635 @option{-i} option has also been used then any inlined functions will
3636 be displayed in the same manner, but on separate lines, and prefixed
3637 by the text @samp{(inlined by)}.
3639 If the file name or function name can not be determined,
3640 @command{addr2line} will print two question marks in their place. If the
3641 line number can not be determined, @command{addr2line} will print 0.
3645 @c man begin OPTIONS addr2line
3647 The long and short forms of options, shown here as alternatives, are
3653 Display the address before the function name, file and line number
3654 information. The address is printed with a @samp{0x} prefix to easily
3657 @item -b @var{bfdname}
3658 @itemx --target=@var{bfdname}
3659 @cindex object code format
3660 Specify that the object-code format for the object files is
3664 @itemx --demangle[=@var{style}]
3665 @cindex demangling in objdump
3666 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3667 Besides removing any initial underscore prepended by the system, this
3668 makes C++ function names readable. Different compilers have different
3669 mangling styles. The optional demangling style argument can be used to
3670 choose an appropriate demangling style for your compiler. @xref{c++filt},
3671 for more information on demangling.
3673 @item -e @var{filename}
3674 @itemx --exe=@var{filename}
3675 Specify the name of the executable for which addresses should be
3676 translated. The default file is @file{a.out}.
3680 Display function names as well as file and line number information.
3684 Display only the base of each file name.
3688 If the address belongs to a function that was inlined, the source
3689 information for all enclosing scopes back to the first non-inlined
3690 function will also be printed. For example, if @code{main} inlines
3691 @code{callee1} which inlines @code{callee2}, and address is from
3692 @code{callee2}, the source information for @code{callee1} and @code{main}
3693 will also be printed.
3697 Read offsets relative to the specified section instead of absolute addresses.
3700 @itemx --pretty-print
3701 Make the output more human friendly: each location are printed on one line.
3702 If option @option{-i} is specified, lines for all enclosing scopes are
3703 prefixed with @samp{(inlined by)}.
3709 @c man begin SEEALSO addr2line
3710 Info entries for @file{binutils}.
3717 @command{windmc} may be used to generator Windows message resources.
3720 @emph{Warning:} @command{windmc} is not always built as part of the binary
3721 utilities, since it is only useful for Windows targets.
3724 @c man title windmc generates Windows message resources.
3727 @c man begin SYNOPSIS windmc
3728 windmc [options] input-file
3732 @c man begin DESCRIPTION windmc
3734 @command{windmc} reads message definitions from an input file (.mc) and
3735 translate them into a set of output files. The output files may be of
3740 A C header file containing the message definitions.
3743 A resource file compilable by the @command{windres} tool.
3746 One or more binary files containing the resource data for a specific
3750 A C include file that maps message id's to their symbolic name.
3753 The exact description of these different formats is available in
3754 documentation from Microsoft.
3756 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3757 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3758 Windows Message Compiler.
3762 @c man begin OPTIONS windmc
3767 Specifies that the input file specified is ASCII. This is the default
3772 Specifies that messages in the output @code{bin} files should be in ASCII
3777 Specifies that @code{bin} filenames should have to be prefixed by the
3778 basename of the source file.
3782 Sets the customer bit in all message id's.
3784 @item -C @var{codepage}
3785 @itemx --codepage_in @var{codepage}
3786 Sets the default codepage to be used to convert input file to UTF16. The
3787 default is ocdepage 1252.
3790 @itemx --decimal_values
3791 Outputs the constants in the header file in decimal. Default is using
3795 @itemx --extension @var{ext}
3796 The extension for the header file. The default is .h extension.
3798 @item -F @var{target}
3799 @itemx --target @var{target}
3800 Specify the BFD format to use for a bin file as output. This
3801 is a BFD target name; you can use the @option{--help} option to see a list
3802 of supported targets. Normally @command{windmc} will use the default
3803 format, which is the first one listed by the @option{--help} option.
3805 @ref{Target Selection}.
3809 @itemx --headerdir @var{path}
3810 The target directory of the generated header file. The default is the
3815 Displays a list of command-line options and then exits.
3817 @item -m @var{characters}
3818 @itemx --maxlength @var{characters}
3819 Instructs @command{windmc} to generate a warning if the length
3820 of any message exceeds the number specified.
3823 @itemx --nullterminate
3824 Terminate message text in @code{bin} files by zero. By default they are
3825 terminated by CR/LF.
3828 @itemx --hresult_use
3829 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3830 file, using HRESULT definitions. Status codes are used if the flag is not
3833 @item -O @var{codepage}
3834 @itemx --codepage_out @var{codepage}
3835 Sets the default codepage to be used to output text files. The default
3839 @itemx --rcdir @var{path}
3840 The target directory for the generated @code{rc} script and the generated
3841 @code{bin} files that the resource compiler script includes. The default
3842 is the current directory.
3846 Specifies that the input file is UTF16.
3849 @itemx --unicode_out
3850 Specifies that messages in the output @code{bin} file should be in UTF16
3851 format. This is the default behaviour.
3855 Enable verbose mode.
3859 Prints the version number for @command{windmc}.
3862 @itemx --xdgb @var{path}
3863 The path of the @code{dbg} C include file that maps message id's to the
3864 symbolic name. No such file is generated without specifying the switch.
3870 @c man begin SEEALSO windmc
3871 the Info entries for @file{binutils}.
3878 @command{windres} may be used to manipulate Windows resources.
3881 @emph{Warning:} @command{windres} is not always built as part of the binary
3882 utilities, since it is only useful for Windows targets.
3885 @c man title windres manipulate Windows resources.
3888 @c man begin SYNOPSIS windres
3889 windres [options] [input-file] [output-file]
3893 @c man begin DESCRIPTION windres
3895 @command{windres} reads resources from an input file and copies them into
3896 an output file. Either file may be in one of three formats:
3900 A text format read by the Resource Compiler.
3903 A binary format generated by the Resource Compiler.
3906 A COFF object or executable.
3909 The exact description of these different formats is available in
3910 documentation from Microsoft.
3912 When @command{windres} converts from the @code{rc} format to the @code{res}
3913 format, it is acting like the Windows Resource Compiler. When
3914 @command{windres} converts from the @code{res} format to the @code{coff}
3915 format, it is acting like the Windows @code{CVTRES} program.
3917 When @command{windres} generates an @code{rc} file, the output is similar
3918 but not identical to the format expected for the input. When an input
3919 @code{rc} file refers to an external filename, an output @code{rc} file
3920 will instead include the file contents.
3922 If the input or output format is not specified, @command{windres} will
3923 guess based on the file name, or, for the input file, the file contents.
3924 A file with an extension of @file{.rc} will be treated as an @code{rc}
3925 file, a file with an extension of @file{.res} will be treated as a
3926 @code{res} file, and a file with an extension of @file{.o} or
3927 @file{.exe} will be treated as a @code{coff} file.
3929 If no output file is specified, @command{windres} will print the resources
3930 in @code{rc} format to standard output.
3932 The normal use is for you to write an @code{rc} file, use @command{windres}
3933 to convert it to a COFF object file, and then link the COFF file into
3934 your application. This will make the resources described in the
3935 @code{rc} file available to Windows.
3939 @c man begin OPTIONS windres
3942 @item -i @var{filename}
3943 @itemx --input @var{filename}
3944 The name of the input file. If this option is not used, then
3945 @command{windres} will use the first non-option argument as the input file
3946 name. If there are no non-option arguments, then @command{windres} will
3947 read from standard input. @command{windres} can not read a COFF file from
3950 @item -o @var{filename}
3951 @itemx --output @var{filename}
3952 The name of the output file. If this option is not used, then
3953 @command{windres} will use the first non-option argument, after any used
3954 for the input file name, as the output file name. If there is no
3955 non-option argument, then @command{windres} will write to standard output.
3956 @command{windres} can not write a COFF file to standard output. Note,
3957 for compatibility with @command{rc} the option @option{-fo} is also
3958 accepted, but its use is not recommended.
3960 @item -J @var{format}
3961 @itemx --input-format @var{format}
3962 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3963 @samp{coff}. If no input format is specified, @command{windres} will
3964 guess, as described above.
3966 @item -O @var{format}
3967 @itemx --output-format @var{format}
3968 The output format to generate. @var{format} may be @samp{res},
3969 @samp{rc}, or @samp{coff}. If no output format is specified,
3970 @command{windres} will guess, as described above.
3972 @item -F @var{target}
3973 @itemx --target @var{target}
3974 Specify the BFD format to use for a COFF file as input or output. This
3975 is a BFD target name; you can use the @option{--help} option to see a list
3976 of supported targets. Normally @command{windres} will use the default
3977 format, which is the first one listed by the @option{--help} option.
3979 @ref{Target Selection}.
3982 @item --preprocessor @var{program}
3983 When @command{windres} reads an @code{rc} file, it runs it through the C
3984 preprocessor first. This option may be used to specify the preprocessor
3985 to use, including any leading arguments. The default preprocessor
3986 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3988 @item --preprocessor-arg @var{option}
3989 When @command{windres} reads an @code{rc} file, it runs it through
3990 the C preprocessor first. This option may be used to specify additional
3991 text to be passed to preprocessor on its command line.
3992 This option can be used multiple times to add multiple options to the
3993 preprocessor command line.
3995 @item -I @var{directory}
3996 @itemx --include-dir @var{directory}
3997 Specify an include directory to use when reading an @code{rc} file.
3998 @command{windres} will pass this to the preprocessor as an @option{-I}
3999 option. @command{windres} will also search this directory when looking for
4000 files named in the @code{rc} file. If the argument passed to this command
4001 matches any of the supported @var{formats} (as described in the @option{-J}
4002 option), it will issue a deprecation warning, and behave just like the
4003 @option{-J} option. New programs should not use this behaviour. If a
4004 directory happens to match a @var{format}, simple prefix it with @samp{./}
4005 to disable the backward compatibility.
4007 @item -D @var{target}
4008 @itemx --define @var{sym}[=@var{val}]
4009 Specify a @option{-D} option to pass to the preprocessor when reading an
4012 @item -U @var{target}
4013 @itemx --undefine @var{sym}
4014 Specify a @option{-U} option to pass to the preprocessor when reading an
4018 Ignored for compatibility with rc.
4021 Enable verbose mode. This tells you what the preprocessor is if you
4025 @item --codepage @var{val}
4026 Specify the default codepage to use when reading an @code{rc} file.
4027 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4028 codepage code. The valid range is from zero up to 0xffff, but the
4029 validity of the codepage is host and configuration dependent.
4032 @item --language @var{val}
4033 Specify the default language to use when reading an @code{rc} file.
4034 @var{val} should be a hexadecimal language code. The low eight bits are
4035 the language, and the high eight bits are the sublanguage.
4037 @item --use-temp-file
4038 Use a temporary file to instead of using popen to read the output of
4039 the preprocessor. Use this option if the popen implementation is buggy
4040 on the host (eg., certain non-English language versions of Windows 95 and
4041 Windows 98 are known to have buggy popen where the output will instead
4044 @item --no-use-temp-file
4045 Use popen, not a temporary file, to read the output of the preprocessor.
4046 This is the default behaviour.
4050 Prints a usage summary.
4054 Prints the version number for @command{windres}.
4057 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4058 this will turn on parser debugging.
4064 @c man begin SEEALSO windres
4065 the Info entries for @file{binutils}.
4074 @command{dlltool} is used to create the files needed to create dynamic
4075 link libraries (DLLs) on systems which understand PE format image
4076 files such as Windows. A DLL contains an export table which contains
4077 information that the runtime loader needs to resolve references from a
4078 referencing program.
4080 The export table is generated by this program by reading in a
4081 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4082 will be in the DLL. A @file{.o} file can contain information in
4083 special @samp{.drectve} sections with export information.
4086 @emph{Note:} @command{dlltool} is not always built as part of the
4087 binary utilities, since it is only useful for those targets which
4091 @c man title dlltool Create files needed to build and use DLLs.
4094 @c man begin SYNOPSIS dlltool
4095 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4096 [@option{-b}|@option{--base-file} @var{base-file-name}]
4097 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4098 [@option{-z}|@option{--output-def} @var{def-file-name}]
4099 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4100 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4101 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4102 [@option{--exclude-symbols} @var{list}]
4103 [@option{--no-default-excludes}]
4104 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4105 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4106 [@option{-a}|@option{--add-indirect}]
4107 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4108 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4109 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4110 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4111 [@option{--use-nul-prefixed-import-tables}]
4112 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4113 [@option{-i}|@option{--interwork}]
4114 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4115 [@option{-v}|@option{--verbose}]
4116 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4117 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4118 [object-file @dots{}]
4122 @c man begin DESCRIPTION dlltool
4124 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4125 @option{-b} options as well as object files specified on the command
4126 line. It then processes these inputs and if the @option{-e} option has
4127 been specified it creates a exports file. If the @option{-l} option
4128 has been specified it creates a library file and if the @option{-z} option
4129 has been specified it creates a def file. Any or all of the @option{-e},
4130 @option{-l} and @option{-z} options can be present in one invocation of
4133 When creating a DLL, along with the source for the DLL, it is necessary
4134 to have three other files. @command{dlltool} can help with the creation of
4137 The first file is a @file{.def} file which specifies which functions are
4138 exported from the DLL, which functions the DLL imports, and so on. This
4139 is a text file and can be created by hand, or @command{dlltool} can be used
4140 to create it using the @option{-z} option. In this case @command{dlltool}
4141 will scan the object files specified on its command line looking for
4142 those functions which have been specially marked as being exported and
4143 put entries for them in the @file{.def} file it creates.
4145 In order to mark a function as being exported from a DLL, it needs to
4146 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4147 section of the object file. This can be done in C by using the
4151 asm (".section .drectve");
4152 asm (".ascii \"-export:my_func\"");
4154 int my_func (void) @{ @dots{} @}
4157 The second file needed for DLL creation is an exports file. This file
4158 is linked with the object files that make up the body of the DLL and it
4159 handles the interface between the DLL and the outside world. This is a
4160 binary file and it can be created by giving the @option{-e} option to
4161 @command{dlltool} when it is creating or reading in a @file{.def} file.
4163 The third file needed for DLL creation is the library file that programs
4164 will link with in order to access the functions in the DLL (an `import
4165 library'). This file can be created by giving the @option{-l} option to
4166 dlltool when it is creating or reading in a @file{.def} file.
4168 If the @option{-y} option is specified, dlltool generates a delay-import
4169 library that can be used instead of the normal import library to allow
4170 a program to link to the dll only as soon as an imported function is
4171 called for the first time. The resulting executable will need to be
4172 linked to the static delayimp library containing __delayLoadHelper2(),
4173 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4175 @command{dlltool} builds the library file by hand, but it builds the
4176 exports file by creating temporary files containing assembler statements
4177 and then assembling these. The @option{-S} command-line option can be
4178 used to specify the path to the assembler that dlltool will use,
4179 and the @option{-f} option can be used to pass specific flags to that
4180 assembler. The @option{-n} can be used to prevent dlltool from deleting
4181 these temporary assembler files when it is done, and if @option{-n} is
4182 specified twice then this will prevent dlltool from deleting the
4183 temporary object files it used to build the library.
4185 Here is an example of creating a DLL from a source file @samp{dll.c} and
4186 also creating a program (from an object file called @samp{program.o})
4191 dlltool -e exports.o -l dll.lib dll.o
4192 gcc dll.o exports.o -o dll.dll
4193 gcc program.o dll.lib -o program
4197 @command{dlltool} may also be used to query an existing import library
4198 to determine the name of the DLL to which it is associated. See the
4199 description of the @option{-I} or @option{--identify} option.
4203 @c man begin OPTIONS dlltool
4205 The command-line options have the following meanings:
4209 @item -d @var{filename}
4210 @itemx --input-def @var{filename}
4211 @cindex input .def file
4212 Specifies the name of a @file{.def} file to be read in and processed.
4214 @item -b @var{filename}
4215 @itemx --base-file @var{filename}
4217 Specifies the name of a base file to be read in and processed. The
4218 contents of this file will be added to the relocation section in the
4219 exports file generated by dlltool.
4221 @item -e @var{filename}
4222 @itemx --output-exp @var{filename}
4223 Specifies the name of the export file to be created by dlltool.
4225 @item -z @var{filename}
4226 @itemx --output-def @var{filename}
4227 Specifies the name of the @file{.def} file to be created by dlltool.
4229 @item -l @var{filename}
4230 @itemx --output-lib @var{filename}
4231 Specifies the name of the library file to be created by dlltool.
4233 @item -y @var{filename}
4234 @itemx --output-delaylib @var{filename}
4235 Specifies the name of the delay-import library file to be created by dlltool.
4237 @item --export-all-symbols
4238 Treat all global and weak defined symbols found in the input object
4239 files as symbols to be exported. There is a small list of symbols which
4240 are not exported by default; see the @option{--no-default-excludes}
4241 option. You may add to the list of symbols to not export by using the
4242 @option{--exclude-symbols} option.
4244 @item --no-export-all-symbols
4245 Only export symbols explicitly listed in an input @file{.def} file or in
4246 @samp{.drectve} sections in the input object files. This is the default
4247 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4248 attributes in the source code.
4250 @item --exclude-symbols @var{list}
4251 Do not export the symbols in @var{list}. This is a list of symbol names
4252 separated by comma or colon characters. The symbol names should not
4253 contain a leading underscore. This is only meaningful when
4254 @option{--export-all-symbols} is used.
4256 @item --no-default-excludes
4257 When @option{--export-all-symbols} is used, it will by default avoid
4258 exporting certain special symbols. The current list of symbols to avoid
4259 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4260 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4261 to go ahead and export these special symbols. This is only meaningful
4262 when @option{--export-all-symbols} is used.
4265 @itemx --as @var{path}
4266 Specifies the path, including the filename, of the assembler to be used
4267 to create the exports file.
4269 @item -f @var{options}
4270 @itemx --as-flags @var{options}
4271 Specifies any specific command-line options to be passed to the
4272 assembler when building the exports file. This option will work even if
4273 the @option{-S} option is not used. This option only takes one argument,
4274 and if it occurs more than once on the command line, then later
4275 occurrences will override earlier occurrences. So if it is necessary to
4276 pass multiple options to the assembler they should be enclosed in
4280 @itemx --dll-name @var{name}
4281 Specifies the name to be stored in the @file{.def} file as the name of
4282 the DLL when the @option{-e} option is used. If this option is not
4283 present, then the filename given to the @option{-e} option will be
4284 used as the name of the DLL.
4286 @item -m @var{machine}
4287 @itemx -machine @var{machine}
4288 Specifies the type of machine for which the library file should be
4289 built. @command{dlltool} has a built in default type, depending upon how
4290 it was created, but this option can be used to override that. This is
4291 normally only useful when creating DLLs for an ARM processor, when the
4292 contents of the DLL are actually encode using Thumb instructions.
4295 @itemx --add-indirect
4296 Specifies that when @command{dlltool} is creating the exports file it
4297 should add a section which allows the exported functions to be
4298 referenced without using the import library. Whatever the hell that
4302 @itemx --add-underscore
4303 Specifies that when @command{dlltool} is creating the exports file it
4304 should prepend an underscore to the names of @emph{all} exported symbols.
4306 @item --no-leading-underscore
4307 @item --leading-underscore
4308 Specifies whether standard symbol should be forced to be prefixed, or
4311 @item --add-stdcall-underscore
4312 Specifies that when @command{dlltool} is creating the exports file it
4313 should prepend an underscore to the names of exported @emph{stdcall}
4314 functions. Variable names and non-stdcall function names are not modified.
4315 This option is useful when creating GNU-compatible import libs for third
4316 party DLLs that were built with MS-Windows tools.
4320 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4321 of stdcall functions that will be imported from the DLL. This is
4322 useful when creating an import library for a DLL which exports stdcall
4323 functions but without the usual @samp{@@<number>} symbol name suffix.
4325 This does not change the naming of symbols provided by the import library
4326 to programs linked against it, but only the entries in the import table
4327 (ie the .idata section).
4330 @itemx --add-stdcall-alias
4331 Specifies that when @command{dlltool} is creating the exports file it
4332 should add aliases for stdcall symbols without @samp{@@ <number>}
4333 in addition to the symbols with @samp{@@ <number>}.
4336 @itemx --ext-prefix-alias @var{prefix}
4337 Causes @command{dlltool} to create external aliases for all DLL
4338 imports with the specified prefix. The aliases are created for both
4339 external and import symbols with no leading underscore.
4343 Specifies that when @command{dlltool} is creating the exports and library
4344 files it should omit the @code{.idata4} section. This is for compatibility
4345 with certain operating systems.
4347 @item --use-nul-prefixed-import-tables
4348 Specifies that when @command{dlltool} is creating the exports and library
4349 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4350 element. This emulates old gnu import library generation of
4351 @code{dlltool}. By default this option is turned off.
4355 Specifies that when @command{dlltool} is creating the exports and library
4356 files it should omit the @code{.idata5} section. This is for compatibility
4357 with certain operating systems.
4359 @item -I @var{filename}
4360 @itemx --identify @var{filename}
4361 Specifies that @command{dlltool} should inspect the import library
4362 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4363 of the associated DLL(s). This can be performed in addition to any
4364 other operations indicated by the other options and arguments.
4365 @command{dlltool} fails if the import library does not exist or is not
4366 actually an import library. See also @option{--identify-strict}.
4368 @item --identify-strict
4369 Modifies the behavior of the @option{--identify} option, such
4370 that an error is reported if @var{filename} is associated with
4375 Specifies that @command{dlltool} should mark the objects in the library
4376 file and exports file that it produces as supporting interworking
4377 between ARM and Thumb code.
4381 Makes @command{dlltool} preserve the temporary assembler files it used to
4382 create the exports file. If this option is repeated then dlltool will
4383 also preserve the temporary object files it uses to create the library
4386 @item -t @var{prefix}
4387 @itemx --temp-prefix @var{prefix}
4388 Makes @command{dlltool} use @var{prefix} when constructing the names of
4389 temporary assembler and object files. By default, the temp file prefix
4390 is generated from the pid.
4394 Make dlltool describe what it is doing.
4398 Displays a list of command-line options and then exits.
4402 Displays dlltool's version number and then exits.
4409 * def file format:: The format of the dlltool @file{.def} file
4412 @node def file format
4413 @section The format of the @command{dlltool} @file{.def} file
4415 A @file{.def} file contains any number of the following commands:
4419 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4420 The result is going to be named @var{name}@code{.exe}.
4422 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4423 The result is going to be named @var{name}@code{.dll}.
4424 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4425 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4428 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4429 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4430 Declares @var{name1} as an exported symbol from the DLL, with optional
4431 ordinal number @var{integer}, or declares @var{name1} as an alias
4432 (forward) of the function @var{external-name} in the DLL.
4433 If @var{its_name} is specified, this name is used as string in export table.
4435 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4436 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4437 If you want to use LIBRARY as name then you need to quote it.
4439 @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{]} *}
4440 Declares that @var{external-name} or the exported function whose
4441 ordinal number is @var{integer} is to be imported from the file
4442 @var{module-name}. If @var{internal-name} is specified then this is
4443 the name that the imported function will be referred to in the body of
4445 If @var{its_name} is specified, this name is used as string in import table.
4446 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4447 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4448 If you want to use LIBRARY as name then you need to quote it.
4450 @item @code{DESCRIPTION} @var{string}
4451 Puts @var{string} into the output @file{.exp} file in the
4452 @code{.rdata} section.
4454 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4455 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4456 Generates @code{--stack} or @code{--heap}
4457 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4458 section. The linker will see this and act upon it.
4460 @item @code{CODE} @var{attr} @code{+}
4461 @item @code{DATA} @var{attr} @code{+}
4462 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4463 Generates @code{--attr} @var{section-name} @var{attr} in the output
4464 @code{.drectve} section, where @var{attr} is one of @code{READ},
4465 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4466 this and act upon it.
4471 @c man begin SEEALSO dlltool
4472 The Info pages for @file{binutils}.
4479 @cindex ELF file information
4482 @c man title readelf Displays information about ELF files.
4485 @c man begin SYNOPSIS readelf
4486 readelf [@option{-a}|@option{--all}]
4487 [@option{-h}|@option{--file-header}]
4488 [@option{-l}|@option{--program-headers}|@option{--segments}]
4489 [@option{-S}|@option{--section-headers}|@option{--sections}]
4490 [@option{-g}|@option{--section-groups}]
4491 [@option{-t}|@option{--section-details}]
4492 [@option{-e}|@option{--headers}]
4493 [@option{-s}|@option{--syms}|@option{--symbols}]
4494 [@option{--dyn-syms}]
4495 [@option{-n}|@option{--notes}]
4496 [@option{-r}|@option{--relocs}]
4497 [@option{-u}|@option{--unwind}]
4498 [@option{-d}|@option{--dynamic}]
4499 [@option{-V}|@option{--version-info}]
4500 [@option{-A}|@option{--arch-specific}]
4501 [@option{-D}|@option{--use-dynamic}]
4502 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4503 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4504 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4505 [@option{-z}|@option{--decompress}]
4506 [@option{-c}|@option{--archive-index}]
4507 [@option{-w[lLiaprmfFsoRtUuTgAckK]}|
4508 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]]
4509 [@option{--dwarf-depth=@var{n}}]
4510 [@option{--dwarf-start=@var{n}}]
4511 [@option{-I}|@option{--histogram}]
4512 [@option{-v}|@option{--version}]
4513 [@option{-W}|@option{--wide}]
4514 [@option{-H}|@option{--help}]
4515 @var{elffile}@dots{}
4519 @c man begin DESCRIPTION readelf
4521 @command{readelf} displays information about one or more ELF format object
4522 files. The options control what particular information to display.
4524 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4525 64-bit ELF files are supported, as are archives containing ELF files.
4527 This program performs a similar function to @command{objdump} but it
4528 goes into more detail and it exists independently of the @sc{bfd}
4529 library, so if there is a bug in @sc{bfd} then readelf will not be
4534 @c man begin OPTIONS readelf
4536 The long and short forms of options, shown here as alternatives, are
4537 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4543 Equivalent to specifying @option{--file-header},
4544 @option{--program-headers}, @option{--sections}, @option{--symbols},
4545 @option{--relocs}, @option{--dynamic}, @option{--notes},
4546 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4547 @option{--section-groups} and @option{--histogram}.
4549 Note - this option does not enable @option{--use-dynamic} itself, so
4550 if that option is not present on the command line then dynamic symbols
4551 and dynamic relocs will not be displayed.
4554 @itemx --file-header
4555 @cindex ELF file header information
4556 Displays the information contained in the ELF header at the start of the
4560 @itemx --program-headers
4562 @cindex ELF program header information
4563 @cindex ELF segment information
4564 Displays the information contained in the file's segment headers, if it
4569 @itemx --section-headers
4570 @cindex ELF section information
4571 Displays the information contained in the file's section headers, if it
4575 @itemx --section-groups
4576 @cindex ELF section group information
4577 Displays the information contained in the file's section groups, if it
4581 @itemx --section-details
4582 @cindex ELF section information
4583 Displays the detailed section information. Implies @option{-S}.
4588 @cindex ELF symbol table information
4589 Displays the entries in symbol table section of the file, if it has one.
4590 If a symbol has version information associated with it then this is
4591 displayed as well. The version string is displayed as a suffix to the
4592 symbol name, preceeded by an @@ character. For example
4593 @samp{foo@@VER_1}. If the version is the default version to be used
4594 when resolving unversioned references to the symbol then it is
4595 displayed as a suffix preceeded by two @@ characters. For example
4596 @samp{foo@@@@VER_2}.
4599 @cindex ELF dynamic symbol table information
4600 Displays the entries in dynamic symbol table section of the file, if it
4601 has one. The output format is the same as the format used by the
4602 @option{--syms} option.
4606 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4611 Displays the contents of the NOTE segments and/or sections, if any.
4615 @cindex ELF reloc information
4616 Displays the contents of the file's relocation section, if it has one.
4620 @cindex unwind information
4621 Displays the contents of the file's unwind section, if it has one. Only
4622 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4623 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
4624 support is not yet implemented for your architecture you could try
4625 dumping the contents of the @var{.eh_frames} section using the
4626 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
4631 @cindex ELF dynamic section information
4632 Displays the contents of the file's dynamic section, if it has one.
4635 @itemx --version-info
4636 @cindex ELF version sections information
4637 Displays the contents of the version sections in the file, it they
4641 @itemx --arch-specific
4642 Displays architecture-specific information in the file, if there
4646 @itemx --use-dynamic
4647 When displaying symbols, this option makes @command{readelf} use the
4648 symbol hash tables in the file's dynamic section, rather than the
4649 symbol table sections.
4651 When displaying relocations, this option makes @command{readelf}
4652 display the dynamic relocations rather than the static relocations.
4654 @item -x <number or name>
4655 @itemx --hex-dump=<number or name>
4656 Displays the contents of the indicated section as a hexadecimal bytes.
4657 A number identifies a particular section by index in the section table;
4658 any other string identifies all sections with that name in the object file.
4660 @item -R <number or name>
4661 @itemx --relocated-dump=<number or name>
4662 Displays the contents of the indicated section as a hexadecimal
4663 bytes. A number identifies a particular section by index in the
4664 section table; any other string identifies all sections with that name
4665 in the object file. The contents of the section will be relocated
4666 before they are displayed.
4668 @item -p <number or name>
4669 @itemx --string-dump=<number or name>
4670 Displays the contents of the indicated section as printable strings.
4671 A number identifies a particular section by index in the section table;
4672 any other string identifies all sections with that name in the object file.
4676 Requests that the section(s) being dumped by @option{x}, @option{R} or
4677 @option{p} options are decompressed before being displayed. If the
4678 section(s) are not compressed then they are displayed as is.
4681 @itemx --archive-index
4682 @cindex Archive file symbol index information
4683 Displays the file symbol index information contained in the header part
4684 of binary archives. Performs the same function as the @option{t}
4685 command to @command{ar}, but without using the BFD library. @xref{ar}.
4687 @item -w[lLiaprmfFsoRtUuTgAckK]
4688 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
4689 @include debug.options.texi
4693 Display a histogram of bucket list lengths when displaying the contents
4694 of the symbol tables.
4698 Display the version number of readelf.
4702 Don't break output lines to fit into 80 columns. By default
4703 @command{readelf} breaks section header and segment listing lines for
4704 64-bit ELF files, so that they fit into 80 columns. This option causes
4705 @command{readelf} to print each section header resp. each segment one a
4706 single line, which is far more readable on terminals wider than 80 columns.
4710 Display the command-line options understood by @command{readelf}.
4717 @c man begin SEEALSO readelf
4718 objdump(1), and the Info entries for @file{binutils}.
4725 @cindex Update ELF header
4728 @c man title elfedit Update the ELF header of ELF files.
4731 @c man begin SYNOPSIS elfedit
4732 elfedit [@option{--input-mach=}@var{machine}]
4733 [@option{--input-type=}@var{type}]
4734 [@option{--input-osabi=}@var{osabi}]
4735 @option{--output-mach=}@var{machine}
4736 @option{--output-type=}@var{type}
4737 @option{--output-osabi=}@var{osabi}
4738 [@option{-v}|@option{--version}]
4739 [@option{-h}|@option{--help}]
4740 @var{elffile}@dots{}
4744 @c man begin DESCRIPTION elfedit
4746 @command{elfedit} updates the ELF header of ELF files which have
4747 the matching ELF machine and file types. The options control how and
4748 which fields in the ELF header should be updated.
4750 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4751 64-bit ELF files are supported, as are archives containing ELF files.
4754 @c man begin OPTIONS elfedit
4756 The long and short forms of options, shown here as alternatives, are
4757 equivalent. At least one of the @option{--output-mach},
4758 @option{--output-type} and @option{--output-osabi} options must be given.
4762 @item --input-mach=@var{machine}
4763 Set the matching input ELF machine type to @var{machine}. If
4764 @option{--input-mach} isn't specified, it will match any ELF
4767 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4768 @var{K1OM} and @var{x86-64}.
4770 @item --output-mach=@var{machine}
4771 Change the ELF machine type in the ELF header to @var{machine}. The
4772 supported ELF machine types are the same as @option{--input-mach}.
4774 @item --input-type=@var{type}
4775 Set the matching input ELF file type to @var{type}. If
4776 @option{--input-type} isn't specified, it will match any ELF file types.
4778 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4780 @item --output-type=@var{type}
4781 Change the ELF file type in the ELF header to @var{type}. The
4782 supported ELF types are the same as @option{--input-type}.
4784 @item --input-osabi=@var{osabi}
4785 Set the matching input ELF file OSABI to @var{osabi}. If
4786 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4788 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4789 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4790 @var{Solaris}, @var{AIX}, @var{Irix},
4791 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4792 @var{NSK}, @var{AROS} and @var{FenixOS}.
4794 @item --output-osabi=@var{osabi}
4795 Change the ELF OSABI in the ELF header to @var{osabi}. The
4796 supported ELF OSABI are the same as @option{--input-osabi}.
4800 Display the version number of @command{elfedit}.
4804 Display the command-line options understood by @command{elfedit}.
4811 @c man begin SEEALSO elfedit
4812 readelf(1), and the Info entries for @file{binutils}.
4816 @node Common Options
4817 @chapter Common Options
4819 The following command-line options are supported by all of the
4820 programs described in this manual.
4822 @c man begin OPTIONS
4824 @include at-file.texi
4828 Display the command-line options supported by the program.
4831 Display the version number of the program.
4833 @c man begin OPTIONS
4837 @node Selecting the Target System
4838 @chapter Selecting the Target System
4840 You can specify two aspects of the target system to the @sc{gnu}
4841 binary file utilities, each in several ways:
4851 In the following summaries, the lists of ways to specify values are in
4852 order of decreasing precedence. The ways listed first override those
4855 The commands to list valid values only list the values for which the
4856 programs you are running were configured. If they were configured with
4857 @option{--enable-targets=all}, the commands list most of the available
4858 values, but a few are left out; not all targets can be configured in at
4859 once because some of them can only be configured @dfn{native} (on hosts
4860 with the same type as the target system).
4863 * Target Selection::
4864 * Architecture Selection::
4867 @node Target Selection
4868 @section Target Selection
4870 A @dfn{target} is an object file format. A given target may be
4871 supported for multiple architectures (@pxref{Architecture Selection}).
4872 A target selection may also have variations for different operating
4873 systems or architectures.
4875 The command to list valid target values is @samp{objdump -i}
4876 (the first column of output contains the relevant information).
4878 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4879 @samp{a.out-sunos-big}.
4881 You can also specify a target using a configuration triplet. This is
4882 the same sort of name that is passed to @file{configure} to specify a
4883 target. When you use a configuration triplet as an argument, it must be
4884 fully canonicalized. You can see the canonical version of a triplet by
4885 running the shell script @file{config.sub} which is included with the
4888 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4889 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4891 @subheading @command{objdump} Target
4897 command-line option: @option{-b} or @option{--target}
4900 environment variable @code{GNUTARGET}
4903 deduced from the input file
4906 @subheading @command{objcopy} and @command{strip} Input Target
4912 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
4915 environment variable @code{GNUTARGET}
4918 deduced from the input file
4921 @subheading @command{objcopy} and @command{strip} Output Target
4927 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
4930 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
4933 environment variable @code{GNUTARGET}
4936 deduced from the input file
4939 @subheading @command{nm}, @command{size}, and @command{strings} Target
4945 command-line option: @option{--target}
4948 environment variable @code{GNUTARGET}
4951 deduced from the input file
4954 @node Architecture Selection
4955 @section Architecture Selection
4957 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4958 to run. Its name may contain a colon, separating the name of the
4959 processor family from the name of the particular @sc{cpu}.
4961 The command to list valid architecture values is @samp{objdump -i} (the
4962 second column contains the relevant information).
4964 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4966 @subheading @command{objdump} Architecture
4972 command-line option: @option{-m} or @option{--architecture}
4975 deduced from the input file
4978 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4984 deduced from the input file
4987 @node Reporting Bugs
4988 @chapter Reporting Bugs
4990 @cindex reporting bugs
4992 Your bug reports play an essential role in making the binary utilities
4995 Reporting a bug may help you by bringing a solution to your problem, or
4996 it may not. But in any case the principal function of a bug report is
4997 to help the entire community by making the next version of the binary
4998 utilities work better. Bug reports are your contribution to their
5001 In order for a bug report to serve its purpose, you must include the
5002 information that enables us to fix the bug.
5005 * Bug Criteria:: Have you found a bug?
5006 * Bug Reporting:: How to report bugs
5010 @section Have You Found a Bug?
5011 @cindex bug criteria
5013 If you are not sure whether you have found a bug, here are some guidelines:
5016 @cindex fatal signal
5019 If a binary utility gets a fatal signal, for any input whatever, that is
5020 a bug. Reliable utilities never crash.
5022 @cindex error on valid input
5024 If a binary utility produces an error message for valid input, that is a
5028 If you are an experienced user of binary utilities, your suggestions for
5029 improvement are welcome in any case.
5033 @section How to Report Bugs
5035 @cindex bugs, reporting
5037 A number of companies and individuals offer support for @sc{gnu}
5038 products. If you obtained the binary utilities from a support
5039 organization, we recommend you contact that organization first.
5041 You can find contact information for many support companies and
5042 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5046 In any event, we also recommend that you send bug reports for the binary
5047 utilities to @value{BUGURL}.
5050 The fundamental principle of reporting bugs usefully is this:
5051 @strong{report all the facts}. If you are not sure whether to state a
5052 fact or leave it out, state it!
5054 Often people omit facts because they think they know what causes the
5055 problem and assume that some details do not matter. Thus, you might
5056 assume that the name of a file you use in an example does not matter.
5057 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5058 a stray memory reference which happens to fetch from the location where
5059 that pathname is stored in memory; perhaps, if the pathname were
5060 different, the contents of that location would fool the utility into
5061 doing the right thing despite the bug. Play it safe and give a
5062 specific, complete example. That is the easiest thing for you to do,
5063 and the most helpful.
5065 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5066 it is new to us. Therefore, always write your bug reports on the assumption
5067 that the bug has not been reported previously.
5069 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5070 bell?'' This cannot help us fix a bug, so it is basically useless. We
5071 respond by asking for enough details to enable us to investigate.
5072 You might as well expedite matters by sending them to begin with.
5074 To enable us to fix the bug, you should include all these things:
5078 The version of the utility. Each utility announces it if you start it
5079 with the @option{--version} argument.
5081 Without this, we will not know whether there is any point in looking for
5082 the bug in the current version of the binary utilities.
5085 Any patches you may have applied to the source, including any patches
5086 made to the @code{BFD} library.
5089 The type of machine you are using, and the operating system name and
5093 What compiler (and its version) was used to compile the utilities---e.g.
5097 The command arguments you gave the utility to observe the bug. To
5098 guarantee you will not omit something important, list them all. A copy
5099 of the Makefile (or the output from make) is sufficient.
5101 If we were to try to guess the arguments, we would probably guess wrong
5102 and then we might not encounter the bug.
5105 A complete input file, or set of input files, that will reproduce the
5106 bug. If the utility is reading an object file or files, then it is
5107 generally most helpful to send the actual object files.
5109 If the source files were produced exclusively using @sc{gnu} programs
5110 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5111 may be OK to send the source files rather than the object files. In
5112 this case, be sure to say exactly what version of @command{gcc}, or
5113 whatever, was used to produce the object files. Also say how
5114 @command{gcc}, or whatever, was configured.
5117 A description of what behavior you observe that you believe is
5118 incorrect. For example, ``It gets a fatal signal.''
5120 Of course, if the bug is that the utility gets a fatal signal, then we
5121 will certainly notice it. But if the bug is incorrect output, we might
5122 not notice unless it is glaringly wrong. You might as well not give us
5123 a chance to make a mistake.
5125 Even if the problem you experience is a fatal signal, you should still
5126 say so explicitly. Suppose something strange is going on, such as your
5127 copy of the utility is out of sync, or you have encountered a bug in
5128 the C library on your system. (This has happened!) Your copy might
5129 crash and ours would not. If you told us to expect a crash, then when
5130 ours fails to crash, we would know that the bug was not happening for
5131 us. If you had not told us to expect a crash, then we would not be able
5132 to draw any conclusion from our observations.
5135 If you wish to suggest changes to the source, send us context diffs, as
5136 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5137 option. Always send diffs from the old file to the new file. If you
5138 wish to discuss something in the @command{ld} source, refer to it by
5139 context, not by line number.
5141 The line numbers in our development sources will not match those in your
5142 sources. Your line numbers would convey no useful information to us.
5145 Here are some things that are not necessary:
5149 A description of the envelope of the bug.
5151 Often people who encounter a bug spend a lot of time investigating
5152 which changes to the input file will make the bug go away and which
5153 changes will not affect it.
5155 This is often time consuming and not very useful, because the way we
5156 will find the bug is by running a single example under the debugger
5157 with breakpoints, not by pure deduction from a series of examples.
5158 We recommend that you save your time for something else.
5160 Of course, if you can find a simpler example to report @emph{instead}
5161 of the original one, that is a convenience for us. Errors in the
5162 output will be easier to spot, running under the debugger will take
5163 less time, and so on.
5165 However, simplification is not vital; if you do not want to do this,
5166 report the bug anyway and send us the entire test case you used.
5169 A patch for the bug.
5171 A patch for the bug does help us if it is a good one. But do not omit
5172 the necessary information, such as the test case, on the assumption that
5173 a patch is all we need. We might see problems with your patch and decide
5174 to fix the problem another way, or we might not understand it at all.
5176 Sometimes with programs as complicated as the binary utilities it is
5177 very hard to construct an example that will make the program follow a
5178 certain path through the code. If you do not send us the example, we
5179 will not be able to construct one, so we will not be able to verify that
5182 And if we cannot understand what bug you are trying to fix, or why your
5183 patch should be an improvement, we will not install it. A test case will
5184 help us to understand.
5187 A guess about what the bug is or what it depends on.
5189 Such guesses are usually wrong. Even we cannot guess right about such
5190 things without first using the debugger to find the facts.
5193 @node GNU Free Documentation License
5194 @appendix GNU Free Documentation License
5198 @node Binutils Index
5199 @unnumbered Binutils Index