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{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1133 [@option{-w}|@option{--wildcard}]
1134 [@option{-x}|@option{--discard-all}]
1135 [@option{-X}|@option{--discard-locals}]
1136 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1137 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1138 [@option{--interleave-width=}@var{width}]
1139 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1140 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1141 [@option{--remove-relocations=}@var{sectionpattern}]
1142 [@option{-p}|@option{--preserve-dates}]
1143 [@option{-D}|@option{--enable-deterministic-archives}]
1144 [@option{-U}|@option{--disable-deterministic-archives}]
1145 [@option{--debugging}]
1146 [@option{--gap-fill=}@var{val}]
1147 [@option{--pad-to=}@var{address}]
1148 [@option{--set-start=}@var{val}]
1149 [@option{--adjust-start=}@var{incr}]
1150 [@option{--change-addresses=}@var{incr}]
1151 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1152 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1153 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1154 [@option{--change-warnings}] [@option{--no-change-warnings}]
1155 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1156 [@option{--add-section} @var{sectionname}=@var{filename}]
1157 [@option{--dump-section} @var{sectionname}=@var{filename}]
1158 [@option{--update-section} @var{sectionname}=@var{filename}]
1159 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1160 [@option{--long-section-names} @{enable,disable,keep@}]
1161 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1162 [@option{--reverse-bytes=}@var{num}]
1163 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1164 [@option{--redefine-sym} @var{old}=@var{new}]
1165 [@option{--redefine-syms=}@var{filename}]
1167 [@option{--keep-symbols=}@var{filename}]
1168 [@option{--strip-symbols=}@var{filename}]
1169 [@option{--strip-unneeded-symbols=}@var{filename}]
1170 [@option{--keep-global-symbols=}@var{filename}]
1171 [@option{--localize-symbols=}@var{filename}]
1172 [@option{--globalize-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.
1385 @item --localize-hidden
1386 In an ELF object, mark all symbols that have hidden or internal visibility
1387 as local. This option applies on top of symbol-specific localization options
1388 such as @option{-L}.
1390 @item -L @var{symbolname}
1391 @itemx --localize-symbol=@var{symbolname}
1392 Convert a global or weak symbol called @var{symbolname} into a local
1393 symbol, so that it is not visible externally. This option may be
1394 given more than once. Note - unique symbols are not converted.
1396 @item -W @var{symbolname}
1397 @itemx --weaken-symbol=@var{symbolname}
1398 Make symbol @var{symbolname} weak. This option may be given more than once.
1400 @item --globalize-symbol=@var{symbolname}
1401 Give symbol @var{symbolname} global scoping so that it is visible
1402 outside of the file in which it is defined. This option may be given
1407 Permit regular expressions in @var{symbolname}s used in other command
1408 line options. The question mark (?), asterisk (*), backslash (\) and
1409 square brackets ([]) operators can be used anywhere in the symbol
1410 name. If the first character of the symbol name is the exclamation
1411 point (!) then the sense of the switch is reversed for that symbol.
1418 would cause objcopy to weaken all symbols that start with ``fo''
1419 except for the symbol ``foo''.
1422 @itemx --discard-all
1423 Do not copy non-global symbols from the source file.
1424 @c FIXME any reason to prefer "non-global" to "local" here?
1427 @itemx --discard-locals
1428 Do not copy compiler-generated local symbols.
1429 (These usually start with @samp{L} or @samp{.}.)
1432 @itemx --byte=@var{byte}
1433 If interleaving has been enabled via the @option{--interleave} option
1434 then start the range of bytes to keep at the @var{byte}th byte.
1435 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1436 @var{breadth} is the value given by the @option{--interleave} option.
1438 @item -i [@var{breadth}]
1439 @itemx --interleave[=@var{breadth}]
1440 Only copy a range out of every @var{breadth} bytes. (Header data is
1441 not affected). Select which byte in the range begins the copy with
1442 the @option{--byte} option. Select the width of the range with the
1443 @option{--interleave-width} option.
1445 This option is useful for creating files to program @sc{rom}. It is
1446 typically used with an @code{srec} output target. Note that
1447 @command{objcopy} will complain if you do not specify the
1448 @option{--byte} option as well.
1450 The default interleave breadth is 4, so with @option{--byte} set to 0,
1451 @command{objcopy} would copy the first byte out of every four bytes
1452 from the input to the output.
1454 @item --interleave-width=@var{width}
1455 When used with the @option{--interleave} option, copy @var{width}
1456 bytes at a time. The start of the range of bytes to be copied is set
1457 by the @option{--byte} option, and the extent of the range is set with
1458 the @option{--interleave} option.
1460 The default value for this option is 1. The value of @var{width} plus
1461 the @var{byte} value set by the @option{--byte} option must not exceed
1462 the interleave breadth set by the @option{--interleave} option.
1464 This option can be used to create images for two 16-bit flashes interleaved
1465 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1466 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1467 commands. If the input was '12345678' then the outputs would be
1468 '1256' and '3478' respectively.
1471 @itemx --preserve-dates
1472 Set the access and modification dates of the output file to be the same
1473 as those of the input file.
1476 @itemx --enable-deterministic-archives
1477 @cindex deterministic archives
1478 @kindex --enable-deterministic-archives
1479 Operate in @emph{deterministic} mode. When copying archive members
1480 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1481 and use consistent file modes for all files.
1483 If @file{binutils} was configured with
1484 @option{--enable-deterministic-archives}, then this mode is on by default.
1485 It can be disabled with the @samp{-U} option, below.
1488 @itemx --disable-deterministic-archives
1489 @cindex deterministic archives
1490 @kindex --enable-deterministic-archives
1491 Do @emph{not} operate in @emph{deterministic} mode. This is the
1492 inverse of the @option{-D} option, above: when copying archive members
1493 and writing the archive index, use their actual UID, GID, timestamp,
1494 and file mode values.
1496 This is the default unless @file{binutils} was configured with
1497 @option{--enable-deterministic-archives}.
1500 Convert debugging information, if possible. This is not the default
1501 because only certain debugging formats are supported, and the
1502 conversion process can be time consuming.
1504 @item --gap-fill @var{val}
1505 Fill gaps between sections with @var{val}. This operation applies to
1506 the @emph{load address} (LMA) of the sections. It is done by increasing
1507 the size of the section with the lower address, and filling in the extra
1508 space created with @var{val}.
1510 @item --pad-to @var{address}
1511 Pad the output file up to the load address @var{address}. This is
1512 done by increasing the size of the last section. The extra space is
1513 filled in with the value specified by @option{--gap-fill} (default zero).
1515 @item --set-start @var{val}
1516 Set the start address of the new file to @var{val}. Not all object file
1517 formats support setting the start address.
1519 @item --change-start @var{incr}
1520 @itemx --adjust-start @var{incr}
1521 @cindex changing start address
1522 Change the start address by adding @var{incr}. Not all object file
1523 formats support setting the start address.
1525 @item --change-addresses @var{incr}
1526 @itemx --adjust-vma @var{incr}
1527 @cindex changing object addresses
1528 Change the VMA and LMA addresses of all sections, as well as the start
1529 address, by adding @var{incr}. Some object file formats do not permit
1530 section addresses to be changed arbitrarily. Note that this does not
1531 relocate the sections; if the program expects sections to be loaded at a
1532 certain address, and this option is used to change the sections such
1533 that they are loaded at a different address, the program may fail.
1535 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1536 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1537 @cindex changing section address
1538 Set or change both the VMA address and the LMA address of any section
1539 matching @var{sectionpattern}. If @samp{=} is used, the section
1540 address is set to @var{val}. Otherwise, @var{val} is added to or
1541 subtracted from the section address. See the comments under
1542 @option{--change-addresses}, above. If @var{sectionpattern} does not
1543 match any sections in the input file, a warning will be issued, unless
1544 @option{--no-change-warnings} is used.
1546 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1547 @cindex changing section LMA
1548 Set or change the LMA address of any sections matching
1549 @var{sectionpattern}. The LMA address is the address where the
1550 section will be loaded into memory at program load time. Normally
1551 this is the same as the VMA address, which is the address of the
1552 section at program run time, but on some systems, especially those
1553 where a program is held in ROM, the two can be different. If @samp{=}
1554 is used, the section address is set to @var{val}. Otherwise,
1555 @var{val} is added to or subtracted from the section address. See the
1556 comments under @option{--change-addresses}, above. If
1557 @var{sectionpattern} does not match any sections in the input file, a
1558 warning will be issued, unless @option{--no-change-warnings} is used.
1560 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1561 @cindex changing section VMA
1562 Set or change the VMA address of any section matching
1563 @var{sectionpattern}. The VMA address is the address where the
1564 section will be located once the program has started executing.
1565 Normally this is the same as the LMA address, which is the address
1566 where the section will be loaded into memory, but on some systems,
1567 especially those where a program is held in ROM, the two can be
1568 different. If @samp{=} is used, the section address is set to
1569 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1570 section address. See the comments under @option{--change-addresses},
1571 above. If @var{sectionpattern} does not match any sections in the
1572 input file, a warning will be issued, unless
1573 @option{--no-change-warnings} is used.
1575 @item --change-warnings
1576 @itemx --adjust-warnings
1577 If @option{--change-section-address} or @option{--change-section-lma} or
1578 @option{--change-section-vma} is used, and the section pattern does not
1579 match any sections, issue a warning. This is the default.
1581 @item --no-change-warnings
1582 @itemx --no-adjust-warnings
1583 Do not issue a warning if @option{--change-section-address} or
1584 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1585 if the section pattern does not match any sections.
1587 @item --set-section-flags @var{sectionpattern}=@var{flags}
1588 Set the flags for any sections matching @var{sectionpattern}. The
1589 @var{flags} argument is a comma separated string of flag names. The
1590 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1591 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1592 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1593 for a section which does not have contents, but it is not meaningful
1594 to clear the @samp{contents} flag of a section which does have
1595 contents--just remove the section instead. Not all flags are
1596 meaningful for all object file formats.
1598 @item --add-section @var{sectionname}=@var{filename}
1599 Add a new section named @var{sectionname} while copying the file. The
1600 contents of the new section are taken from the file @var{filename}. The
1601 size of the section will be the size of the file. This option only
1602 works on file formats which can support sections with arbitrary names.
1603 Note - it may be necessary to use the @option{--set-section-flags}
1604 option to set the attributes of the newly created section.
1606 @item --dump-section @var{sectionname}=@var{filename}
1607 Place the contents of section named @var{sectionname} into the file
1608 @var{filename}, overwriting any contents that may have been there
1609 previously. This option is the inverse of @option{--add-section}.
1610 This option is similar to the @option{--only-section} option except
1611 that it does not create a formatted file, it just dumps the contents
1612 as raw binary data, without applying any relocations. The option can
1613 be specified more than once.
1615 @item --update-section @var{sectionname}=@var{filename}
1616 Replace the existing contents of a section named @var{sectionname}
1617 with the contents of file @var{filename}. The size of the section
1618 will be adjusted to the size of the file. The section flags for
1619 @var{sectionname} will be unchanged. For ELF format files the section
1620 to segment mapping will also remain unchanged, something which is not
1621 possible using @option{--remove-section} followed by
1622 @option{--add-section}. The option can be specified more than once.
1624 Note - it is possible to use @option{--rename-section} and
1625 @option{--update-section} to both update and rename a section from one
1626 command line. In this case, pass the original section name to
1627 @option{--update-section}, and the original and new section names to
1628 @option{--rename-section}.
1630 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1631 Add a new symbol named @var{name} while copying the file. This option may be
1632 specified multiple times. If the @var{section} is given, the symbol will be
1633 associated with and relative to that section, otherwise it will be an ABS
1634 symbol. Specifying an undefined section will result in a fatal error. There
1635 is no check for the value, it will be taken as specified. Symbol flags can
1636 be specified and not all flags will be meaningful for all object file
1637 formats. By default, the symbol will be global. The special flag
1638 'before=@var{othersym}' will insert the new symbol in front of the specified
1639 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1640 symbol table in the order they appear.
1642 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1643 Rename a section from @var{oldname} to @var{newname}, optionally
1644 changing the section's flags to @var{flags} in the process. This has
1645 the advantage over using a linker script to perform the rename in that
1646 the output stays as an object file and does not become a linked
1649 This option is particularly helpful when the input format is binary,
1650 since this will always create a section called .data. If for example,
1651 you wanted instead to create a section called .rodata containing binary
1652 data you could use the following command line to achieve it:
1655 objcopy -I binary -O <output_format> -B <architecture> \
1656 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1657 <input_binary_file> <output_object_file>
1660 @item --long-section-names @{enable,disable,keep@}
1661 Controls the handling of long section names when processing @code{COFF}
1662 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1663 is to preserve long section names if any are present in the input file.
1664 The @samp{enable} and @samp{disable} options forcibly enable or disable
1665 the use of long section names in the output object; when @samp{disable}
1666 is in effect, any long section names in the input object will be truncated.
1667 The @samp{enable} option will only emit long section names if any are
1668 present in the inputs; this is mostly the same as @samp{keep}, but it
1669 is left undefined whether the @samp{enable} option might force the
1670 creation of an empty string table in the output file.
1672 @item --change-leading-char
1673 Some object file formats use special characters at the start of
1674 symbols. The most common such character is underscore, which compilers
1675 often add before every symbol. This option tells @command{objcopy} to
1676 change the leading character of every symbol when it converts between
1677 object file formats. If the object file formats use the same leading
1678 character, this option has no effect. Otherwise, it will add a
1679 character, or remove a character, or change a character, as
1682 @item --remove-leading-char
1683 If the first character of a global symbol is a special symbol leading
1684 character used by the object file format, remove the character. The
1685 most common symbol leading character is underscore. This option will
1686 remove a leading underscore from all global symbols. This can be useful
1687 if you want to link together objects of different file formats with
1688 different conventions for symbol names. This is different from
1689 @option{--change-leading-char} because it always changes the symbol name
1690 when appropriate, regardless of the object file format of the output
1693 @item --reverse-bytes=@var{num}
1694 Reverse the bytes in a section with output contents. A section length must
1695 be evenly divisible by the value given in order for the swap to be able to
1696 take place. Reversing takes place before the interleaving is performed.
1698 This option is used typically in generating ROM images for problematic
1699 target systems. For example, on some target boards, the 32-bit words
1700 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1701 regardless of the CPU byte order. Depending on the programming model, the
1702 endianness of the ROM may need to be modified.
1704 Consider a simple file with a section containing the following eight
1705 bytes: @code{12345678}.
1707 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1708 output file would be ordered @code{21436587}.
1710 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1711 output file would be ordered @code{43218765}.
1713 By using @samp{--reverse-bytes=2} for the above example, followed by
1714 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1715 output file would be ordered @code{34127856}.
1717 @item --srec-len=@var{ival}
1718 Meaningful only for srec output. Set the maximum length of the Srecords
1719 being produced to @var{ival}. This length covers both address, data and
1722 @item --srec-forceS3
1723 Meaningful only for srec output. Avoid generation of S1/S2 records,
1724 creating S3-only record format.
1726 @item --redefine-sym @var{old}=@var{new}
1727 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1728 when one is trying link two things together for which you have no
1729 source, and there are name collisions.
1731 @item --redefine-syms=@var{filename}
1732 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1733 listed in the file @var{filename}. @var{filename} is simply a flat file,
1734 with one symbol pair per line. Line comments may be introduced by the hash
1735 character. This option may be given more than once.
1738 Change all global symbols in the file to be weak. This can be useful
1739 when building an object which will be linked against other objects using
1740 the @option{-R} option to the linker. This option is only effective when
1741 using an object file format which supports weak symbols.
1743 @item --keep-symbols=@var{filename}
1744 Apply @option{--keep-symbol} option to each symbol listed in the file
1745 @var{filename}. @var{filename} is simply a flat file, with one symbol
1746 name per line. Line comments may be introduced by the hash character.
1747 This option may be given more than once.
1749 @item --strip-symbols=@var{filename}
1750 Apply @option{--strip-symbol} option to each symbol listed in the file
1751 @var{filename}. @var{filename} is simply a flat file, with one symbol
1752 name per line. Line comments may be introduced by the hash character.
1753 This option may be given more than once.
1755 @item --strip-unneeded-symbols=@var{filename}
1756 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1757 the file @var{filename}. @var{filename} is simply a flat file, with one
1758 symbol name per line. Line comments may be introduced by the hash
1759 character. This option may be given more than once.
1761 @item --keep-global-symbols=@var{filename}
1762 Apply @option{--keep-global-symbol} option to each symbol listed in the
1763 file @var{filename}. @var{filename} is simply a flat file, with one
1764 symbol name per line. Line comments may be introduced by the hash
1765 character. This option may be given more than once.
1767 @item --localize-symbols=@var{filename}
1768 Apply @option{--localize-symbol} option to each symbol listed in the file
1769 @var{filename}. @var{filename} is simply a flat file, with one symbol
1770 name per line. Line comments may be introduced by the hash character.
1771 This option may be given more than once.
1773 @item --globalize-symbols=@var{filename}
1774 Apply @option{--globalize-symbol} option to each symbol listed in the file
1775 @var{filename}. @var{filename} is simply a flat file, with one symbol
1776 name per line. Line comments may be introduced by the hash character.
1777 This option may be given more than once.
1779 @item --weaken-symbols=@var{filename}
1780 Apply @option{--weaken-symbol} option to each symbol listed in the file
1781 @var{filename}. @var{filename} is simply a flat file, with one symbol
1782 name per line. Line comments may be introduced by the hash character.
1783 This option may be given more than once.
1785 @item --alt-machine-code=@var{index}
1786 If the output architecture has alternate machine codes, use the
1787 @var{index}th code instead of the default one. This is useful in case
1788 a machine is assigned an official code and the tool-chain adopts the
1789 new code, but other applications still depend on the original code
1790 being used. For ELF based architectures if the @var{index}
1791 alternative does not exist then the value is treated as an absolute
1792 number to be stored in the e_machine field of the ELF header.
1794 @item --writable-text
1795 Mark the output text as writable. This option isn't meaningful for all
1796 object file formats.
1798 @item --readonly-text
1799 Make the output text write protected. This option isn't meaningful for all
1800 object file formats.
1803 Mark the output file as demand paged. This option isn't meaningful for all
1804 object file formats.
1807 Mark the output file as impure. This option isn't meaningful for all
1808 object file formats.
1810 @item --prefix-symbols=@var{string}
1811 Prefix all symbols in the output file with @var{string}.
1813 @item --prefix-sections=@var{string}
1814 Prefix all section names in the output file with @var{string}.
1816 @item --prefix-alloc-sections=@var{string}
1817 Prefix all the names of all allocated sections in the output file with
1820 @item --add-gnu-debuglink=@var{path-to-file}
1821 Creates a .gnu_debuglink section which contains a reference to
1822 @var{path-to-file} and adds it to the output file. Note: the file at
1823 @var{path-to-file} must exist. Part of the process of adding the
1824 .gnu_debuglink section involves embedding a checksum of the contents
1825 of the debug info file into the section.
1827 If the debug info file is built in one location but it is going to be
1828 installed at a later time into a different location then do not use
1829 the path to the installed location. The @option{--add-gnu-debuglink}
1830 option will fail because the installed file does not exist yet.
1831 Instead put the debug info file in the current directory and use the
1832 @option{--add-gnu-debuglink} option without any directory components,
1836 objcopy --add-gnu-debuglink=foo.debug
1839 At debug time the debugger will attempt to look for the separate debug
1840 info file in a set of known locations. The exact set of these
1841 locations varies depending upon the distribution being used, but it
1846 @item * The same directory as the executable.
1848 @item * A sub-directory of the directory containing the executable
1851 @item * A global debug directory such as /usr/lib/debug.
1854 As long as the debug info file has been installed into one of these
1855 locations before the debugger is run everything should work
1858 @item --keep-file-symbols
1859 When stripping a file, perhaps with @option{--strip-debug} or
1860 @option{--strip-unneeded}, retain any symbols specifying source file names,
1861 which would otherwise get stripped.
1863 @item --only-keep-debug
1864 Strip a file, removing contents of any sections that would not be
1865 stripped by @option{--strip-debug} and leaving the debugging sections
1866 intact. In ELF files, this preserves all note sections in the output.
1868 Note - the section headers of the stripped sections are preserved,
1869 including their sizes, but the contents of the section are discarded.
1870 The section headers are preserved so that other tools can match up the
1871 debuginfo file with the real executable, even if that executable has
1872 been relocated to a different address space.
1874 The intention is that this option will be used in conjunction with
1875 @option{--add-gnu-debuglink} to create a two part executable. One a
1876 stripped binary which will occupy less space in RAM and in a
1877 distribution and the second a debugging information file which is only
1878 needed if debugging abilities are required. The suggested procedure
1879 to create these files is as follows:
1882 @item Link the executable as normal. Assuming that it is called
1884 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1885 create a file containing the debugging info.
1886 @item Run @code{objcopy --strip-debug foo} to create a
1887 stripped executable.
1888 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1889 to add a link to the debugging info into the stripped executable.
1892 Note---the choice of @code{.dbg} as an extension for the debug info
1893 file is arbitrary. Also the @code{--only-keep-debug} step is
1894 optional. You could instead do this:
1897 @item Link the executable as normal.
1898 @item Copy @code{foo} to @code{foo.full}
1899 @item Run @code{objcopy --strip-debug foo}
1900 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1903 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1904 full executable. It does not have to be a file created by the
1905 @option{--only-keep-debug} switch.
1907 Note---this switch is only intended for use on fully linked files. It
1908 does not make sense to use it on object files where the debugging
1909 information may be incomplete. Besides the gnu_debuglink feature
1910 currently only supports the presence of one filename containing
1911 debugging information, not multiple filenames on a one-per-object-file
1915 Remove the contents of all DWARF .dwo sections, leaving the
1916 remaining debugging sections and all symbols intact.
1917 This option is intended for use by the compiler as part of
1918 the @option{-gsplit-dwarf} option, which splits debug information
1919 between the .o file and a separate .dwo file. The compiler
1920 generates all debug information in the same file, then uses
1921 the @option{--extract-dwo} option to copy the .dwo sections to
1922 the .dwo file, then the @option{--strip-dwo} option to remove
1923 those sections from the original .o file.
1926 Extract the contents of all DWARF .dwo sections. See the
1927 @option{--strip-dwo} option for more information.
1929 @item --file-alignment @var{num}
1930 Specify the file alignment. Sections in the file will always begin at
1931 file offsets which are multiples of this number. This defaults to
1933 [This option is specific to PE targets.]
1935 @item --heap @var{reserve}
1936 @itemx --heap @var{reserve},@var{commit}
1937 Specify the number of bytes of memory to reserve (and optionally commit)
1938 to be used as heap for this program.
1939 [This option is specific to PE targets.]
1941 @item --image-base @var{value}
1942 Use @var{value} as the base address of your program or dll. This is
1943 the lowest memory location that will be used when your program or dll
1944 is loaded. To reduce the need to relocate and improve performance of
1945 your dlls, each should have a unique base address and not overlap any
1946 other dlls. The default is 0x400000 for executables, and 0x10000000
1948 [This option is specific to PE targets.]
1950 @item --section-alignment @var{num}
1951 Sets the section alignment. Sections in memory will always begin at
1952 addresses which are a multiple of this number. Defaults to 0x1000.
1953 [This option is specific to PE targets.]
1955 @item --stack @var{reserve}
1956 @itemx --stack @var{reserve},@var{commit}
1957 Specify the number of bytes of memory to reserve (and optionally commit)
1958 to be used as stack for this program.
1959 [This option is specific to PE targets.]
1961 @item --subsystem @var{which}
1962 @itemx --subsystem @var{which}:@var{major}
1963 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1964 Specifies the subsystem under which your program will execute. The
1965 legal values for @var{which} are @code{native}, @code{windows},
1966 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1967 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1968 the subsystem version also. Numeric values are also accepted for
1970 [This option is specific to PE targets.]
1972 @item --extract-symbol
1973 Keep the file's section flags and symbols but remove all section data.
1974 Specifically, the option:
1977 @item removes the contents of all sections;
1978 @item sets the size of every section to zero; and
1979 @item sets the file's start address to zero.
1982 This option is used to build a @file{.sym} file for a VxWorks kernel.
1983 It can also be a useful way of reducing the size of a @option{--just-symbols}
1986 @item --compress-debug-sections
1987 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
1988 ELF ABI. Note - if compression would actually make a section
1989 @emph{larger}, then it is not compressed.
1991 @item --compress-debug-sections=none
1992 @itemx --compress-debug-sections=zlib
1993 @itemx --compress-debug-sections=zlib-gnu
1994 @itemx --compress-debug-sections=zlib-gabi
1995 For ELF files, these options control how DWARF debug sections are
1996 compressed. @option{--compress-debug-sections=none} is equivalent
1997 to @option{--decompress-debug-sections}.
1998 @option{--compress-debug-sections=zlib} and
1999 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2000 @option{--compress-debug-sections}.
2001 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
2002 sections using zlib. The debug sections are renamed to begin with
2003 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
2004 actually make a section @emph{larger}, then it is not compressed nor
2007 @item --decompress-debug-sections
2008 Decompress DWARF debug sections using zlib. The original section
2009 names of the compressed sections are restored.
2011 @item --elf-stt-common=yes
2012 @itemx --elf-stt-common=no
2013 For ELF files, these options control whether common symbols should be
2014 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2015 @option{--elf-stt-common=yes} converts common symbol type to
2016 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2017 type to @code{STT_OBJECT}.
2020 @itemx --no-merge-notes
2021 For ELF files, attempt (or do not attempt) to reduce the size of any
2022 SHT_NOTE type sections by removing duplicate notes.
2026 Show the version number of @command{objcopy}.
2030 Verbose output: list all object files modified. In the case of
2031 archives, @samp{objcopy -V} lists all members of the archive.
2034 Show a summary of the options to @command{objcopy}.
2037 Display a list showing all architectures and object formats available.
2043 @c man begin SEEALSO objcopy
2044 ld(1), objdump(1), and the Info entries for @file{binutils}.
2051 @cindex object file information
2054 @c man title objdump display information from object files.
2057 @c man begin SYNOPSIS objdump
2058 objdump [@option{-a}|@option{--archive-headers}]
2059 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2060 [@option{-C}|@option{--demangle}[=@var{style}] ]
2061 [@option{-d}|@option{--disassemble}]
2062 [@option{-D}|@option{--disassemble-all}]
2063 [@option{-z}|@option{--disassemble-zeroes}]
2064 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2065 [@option{-f}|@option{--file-headers}]
2066 [@option{-F}|@option{--file-offsets}]
2067 [@option{--file-start-context}]
2068 [@option{-g}|@option{--debugging}]
2069 [@option{-e}|@option{--debugging-tags}]
2070 [@option{-h}|@option{--section-headers}|@option{--headers}]
2071 [@option{-i}|@option{--info}]
2072 [@option{-j} @var{section}|@option{--section=}@var{section}]
2073 [@option{-l}|@option{--line-numbers}]
2074 [@option{-S}|@option{--source}]
2075 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2076 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2077 [@option{-p}|@option{--private-headers}]
2078 [@option{-P} @var{options}|@option{--private=}@var{options}]
2079 [@option{-r}|@option{--reloc}]
2080 [@option{-R}|@option{--dynamic-reloc}]
2081 [@option{-s}|@option{--full-contents}]
2082 [@option{-W[lLiaprmfFsoRtUuTgAckK]}|
2083 @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]]
2084 [@option{-G}|@option{--stabs}]
2085 [@option{-t}|@option{--syms}]
2086 [@option{-T}|@option{--dynamic-syms}]
2087 [@option{-x}|@option{--all-headers}]
2088 [@option{-w}|@option{--wide}]
2089 [@option{--start-address=}@var{address}]
2090 [@option{--stop-address=}@var{address}]
2091 [@option{--prefix-addresses}]
2092 [@option{--[no-]show-raw-insn}]
2093 [@option{--adjust-vma=}@var{offset}]
2094 [@option{--dwarf-depth=@var{n}}]
2095 [@option{--dwarf-start=@var{n}}]
2096 [@option{--special-syms}]
2097 [@option{--prefix=}@var{prefix}]
2098 [@option{--prefix-strip=}@var{level}]
2099 [@option{--insn-width=}@var{width}]
2100 [@option{-V}|@option{--version}]
2101 [@option{-H}|@option{--help}]
2102 @var{objfile}@dots{}
2106 @c man begin DESCRIPTION objdump
2108 @command{objdump} displays information about one or more object files.
2109 The options control what particular information to display. This
2110 information is mostly useful to programmers who are working on the
2111 compilation tools, as opposed to programmers who just want their
2112 program to compile and work.
2114 @var{objfile}@dots{} are the object files to be examined. When you
2115 specify archives, @command{objdump} shows information on each of the member
2120 @c man begin OPTIONS objdump
2122 The long and short forms of options, shown here as alternatives, are
2123 equivalent. At least one option from the list
2124 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2128 @itemx --archive-header
2129 @cindex archive headers
2130 If any of the @var{objfile} files are archives, display the archive
2131 header information (in a format similar to @samp{ls -l}). Besides the
2132 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2133 the object file format of each archive member.
2135 @item --adjust-vma=@var{offset}
2136 @cindex section addresses in objdump
2137 @cindex VMA in objdump
2138 When dumping information, first add @var{offset} to all the section
2139 addresses. This is useful if the section addresses do not correspond to
2140 the symbol table, which can happen when putting sections at particular
2141 addresses when using a format which can not represent section addresses,
2144 @item -b @var{bfdname}
2145 @itemx --target=@var{bfdname}
2146 @cindex object code format
2147 Specify that the object-code format for the object files is
2148 @var{bfdname}. This option may not be necessary; @var{objdump} can
2149 automatically recognize many formats.
2153 objdump -b oasys -m vax -h fu.o
2156 displays summary information from the section headers (@option{-h}) of
2157 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2158 file in the format produced by Oasys compilers. You can list the
2159 formats available with the @option{-i} option.
2160 @xref{Target Selection}, for more information.
2163 @itemx --demangle[=@var{style}]
2164 @cindex demangling in objdump
2165 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2166 Besides removing any initial underscore prepended by the system, this
2167 makes C++ function names readable. Different compilers have different
2168 mangling styles. The optional demangling style argument can be used to
2169 choose an appropriate demangling style for your compiler. @xref{c++filt},
2170 for more information on demangling.
2174 Display debugging information. This attempts to parse STABS
2175 debugging format information stored in the file and print it out using
2176 a C like syntax. If no STABS debuging was found this option
2177 falls back on the @option{-W} option to print any DWARF information in
2181 @itemx --debugging-tags
2182 Like @option{-g}, but the information is generated in a format compatible
2186 @itemx --disassemble
2187 @cindex disassembling object code
2188 @cindex machine instructions
2189 Display the assembler mnemonics for the machine instructions from
2190 @var{objfile}. This option only disassembles those sections which are
2191 expected to contain instructions.
2194 @itemx --disassemble-all
2195 Like @option{-d}, but disassemble the contents of all sections, not just
2196 those expected to contain instructions.
2198 This option also has a subtle effect on the disassembly of
2199 instructions in code sections. When option @option{-d} is in effect
2200 objdump will assume that any symbols present in a code section occur
2201 on the boundary between instructions and it will refuse to disassemble
2202 across such a boundary. When option @option{-D} is in effect however
2203 this assumption is supressed. This means that it is possible for the
2204 output of @option{-d} and @option{-D} to differ if, for example, data
2205 is stored in code sections.
2207 If the target is an ARM architecture this switch also has the effect
2208 of forcing the disassembler to decode pieces of data found in code
2209 sections as if they were instructions.
2211 @item --prefix-addresses
2212 When disassembling, print the complete address on each line. This is
2213 the older disassembly format.
2217 @itemx --endian=@{big|little@}
2219 @cindex disassembly endianness
2220 Specify the endianness of the object files. This only affects
2221 disassembly. This can be useful when disassembling a file format which
2222 does not describe endianness information, such as S-records.
2225 @itemx --file-headers
2226 @cindex object file header
2227 Display summary information from the overall header of
2228 each of the @var{objfile} files.
2231 @itemx --file-offsets
2232 @cindex object file offsets
2233 When disassembling sections, whenever a symbol is displayed, also
2234 display the file offset of the region of data that is about to be
2235 dumped. If zeroes are being skipped, then when disassembly resumes,
2236 tell the user how many zeroes were skipped and the file offset of the
2237 location from where the disassembly resumes. When dumping sections,
2238 display the file offset of the location from where the dump starts.
2240 @item --file-start-context
2241 @cindex source code context
2242 Specify that when displaying interlisted source code/disassembly
2243 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2244 context to the start of the file.
2247 @itemx --section-headers
2249 @cindex section headers
2250 Display summary information from the section headers of the
2253 File segments may be relocated to nonstandard addresses, for example by
2254 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2255 @command{ld}. However, some object file formats, such as a.out, do not
2256 store the starting address of the file segments. In those situations,
2257 although @command{ld} relocates the sections correctly, using @samp{objdump
2258 -h} to list the file section headers cannot show the correct addresses.
2259 Instead, it shows the usual addresses, which are implicit for the
2262 Note, in some cases it is possible for a section to have both the
2263 READONLY and the NOREAD attributes set. In such cases the NOREAD
2264 attribute takes precedence, but @command{objdump} will report both
2265 since the exact setting of the flag bits might be important.
2269 Print a summary of the options to @command{objdump} and exit.
2273 @cindex architectures available
2274 @cindex object formats available
2275 Display a list showing all architectures and object formats available
2276 for specification with @option{-b} or @option{-m}.
2279 @itemx --section=@var{name}
2280 @cindex section information
2281 Display information only for section @var{name}.
2284 @itemx --line-numbers
2285 @cindex source filenames for object files
2286 Label the display (using debugging information) with the filename and
2287 source line numbers corresponding to the object code or relocs shown.
2288 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2290 @item -m @var{machine}
2291 @itemx --architecture=@var{machine}
2292 @cindex architecture
2293 @cindex disassembly architecture
2294 Specify the architecture to use when disassembling object files. This
2295 can be useful when disassembling object files which do not describe
2296 architecture information, such as S-records. You can list the available
2297 architectures with the @option{-i} option.
2299 If the target is an ARM architecture then this switch has an
2300 additional effect. It restricts the disassembly to only those
2301 instructions supported by the architecture specified by @var{machine}.
2302 If it is necessary to use this switch because the input file does not
2303 contain any architecture information, but it is also desired to
2304 disassemble all the instructions use @option{-marm}.
2306 @item -M @var{options}
2307 @itemx --disassembler-options=@var{options}
2308 Pass target specific information to the disassembler. Only supported on
2309 some targets. If it is necessary to specify more than one
2310 disassembler option then multiple @option{-M} options can be used or
2311 can be placed together into a comma separated list.
2313 For ARC, @option{dsp} controls the printing of DSP instructions,
2314 @option{spfp} selects the printing of FPX single precision FP
2315 instructions, @option{dpfp} selects the printing of FPX double
2316 precision FP instructions, @option{quarkse_em} selects the printing of
2317 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2318 of double precision assist instructions, @option{fpus} selects the
2319 printing of FPU single precision FP instructions, while @option{fpud}
2320 selects the printing of FPU double precision FP instructions.
2321 Additionally, one can choose to have all the immediates printed in
2322 hexadecimal using @option{hex}. By default, the short immediates are
2323 printed using the decimal representation, while the long immediate
2324 values are printed as hexadecimal.
2326 @option{cpu=...} allows to enforce a particular ISA when disassembling
2327 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2328 This might be useful to select ARC EM or HS ISA, because architecture is same
2329 for those and disassembler relies on private ELF header data to decide if code
2330 is for EM or HS. This option might be specified multiple times - only the
2331 latest value will be used. Valid values are same as for the assembler
2332 @option{-mcpu=...} option.
2334 If the target is an ARM architecture then this switch can be used to
2335 select which register name set is used during disassembler. Specifying
2336 @option{-M reg-names-std} (the default) will select the register names as
2337 used in ARM's instruction set documentation, but with register 13 called
2338 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2339 @option{-M reg-names-apcs} will select the name set used by the ARM
2340 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2341 just use @samp{r} followed by the register number.
2343 There are also two variants on the APCS register naming scheme enabled
2344 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2345 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2346 with the normal register names or the special register names).
2348 This option can also be used for ARM architectures to force the
2349 disassembler to interpret all instructions as Thumb instructions by
2350 using the switch @option{--disassembler-options=force-thumb}. This can be
2351 useful when attempting to disassemble thumb code produced by other
2354 For AArch64 targets this switch can be used to set whether instructions are
2355 disassembled as the most general instruction using the @option{-M no-aliases}
2356 option or whether instruction notes should be generated as comments in the
2357 disasssembly using @option{-M notes}.
2359 For the x86, some of the options duplicate functions of the @option{-m}
2360 switch, but allow finer grained control. Multiple selections from the
2361 following may be specified as a comma separated string.
2366 Select disassembly for the given architecture.
2370 Select between intel syntax mode and AT&T syntax mode.
2374 Select between AMD64 ISA and Intel64 ISA.
2376 @item intel-mnemonic
2378 Select between intel mnemonic mode and AT&T mnemonic mode.
2379 Note: @code{intel-mnemonic} implies @code{intel} and
2380 @code{att-mnemonic} implies @code{att}.
2387 Specify the default address size and operand size. These four options
2388 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2389 appear later in the option string.
2392 When in AT&T mode, instructs the disassembler to print a mnemonic
2393 suffix even when the suffix could be inferred by the operands.
2396 For PowerPC, the @option{-M} argument @option{raw} selects
2397 disasssembly of hardware insns rather than aliases. For example, you
2398 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2399 rather than @code{li}. All of the @option{-m} arguments for
2400 @command{gas} that select a CPU are supported. These are:
2401 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2402 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2403 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2404 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2405 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2406 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2407 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2408 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2409 @option{power8}, @option{power9}, @option{ppc}, @option{ppc32},
2410 @option{ppc64}, @option{ppc64bridge}, @option{ppcps}, @option{pwr},
2411 @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2412 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2413 @option{pwrx}, @option{titan}, and @option{vle}.
2414 @option{32} and @option{64} modify the default or a prior CPU
2415 selection, disabling and enabling 64-bit insns respectively. In
2416 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2417 and @option{spe} add capabilities to a previous @emph{or later} CPU
2418 selection. @option{any} will disassemble any opcode known to
2419 binutils, but in cases where an opcode has two different meanings or
2420 different arguments, you may not see the disassembly you expect.
2421 If you disassemble without giving a CPU selection, a default will be
2422 chosen from information gleaned by BFD from the object files headers,
2423 but the result again may not be as you expect.
2425 For MIPS, this option controls the printing of instruction mnemonic
2426 names and register names in disassembled instructions. Multiple
2427 selections from the following may be specified as a comma separated
2428 string, and invalid options are ignored:
2432 Print the 'raw' instruction mnemonic instead of some pseudo
2433 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2434 'sll' instead of 'nop', etc.
2437 Disassemble MSA instructions.
2440 Disassemble the virtualization ASE instructions.
2443 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2445 @item gpr-names=@var{ABI}
2446 Print GPR (general-purpose register) names as appropriate
2447 for the specified ABI. By default, GPR names are selected according to
2448 the ABI of the binary being disassembled.
2450 @item fpr-names=@var{ABI}
2451 Print FPR (floating-point register) names as
2452 appropriate for the specified ABI. By default, FPR numbers are printed
2455 @item cp0-names=@var{ARCH}
2456 Print CP0 (system control coprocessor; coprocessor 0) register names
2457 as appropriate for the CPU or architecture specified by
2458 @var{ARCH}. By default, CP0 register names are selected according to
2459 the architecture and CPU of the binary being disassembled.
2461 @item hwr-names=@var{ARCH}
2462 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2463 as appropriate for the CPU or architecture specified by
2464 @var{ARCH}. By default, HWR names are selected according to
2465 the architecture and CPU of the binary being disassembled.
2467 @item reg-names=@var{ABI}
2468 Print GPR and FPR names as appropriate for the selected ABI.
2470 @item reg-names=@var{ARCH}
2471 Print CPU-specific register names (CP0 register and HWR names)
2472 as appropriate for the selected CPU or architecture.
2475 For any of the options listed above, @var{ABI} or
2476 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2477 rather than names, for the selected types of registers.
2478 You can list the available values of @var{ABI} and @var{ARCH} using
2479 the @option{--help} option.
2481 For VAX, you can specify function entry addresses with @option{-M
2482 entry:0xf00ba}. You can use this multiple times to properly
2483 disassemble VAX binary files that don't contain symbol tables (like
2484 ROM dumps). In these cases, the function entry mask would otherwise
2485 be decoded as VAX instructions, which would probably lead the rest
2486 of the function being wrongly disassembled.
2489 @itemx --private-headers
2490 Print information that is specific to the object file format. The exact
2491 information printed depends upon the object file format. For some
2492 object file formats, no additional information is printed.
2494 @item -P @var{options}
2495 @itemx --private=@var{options}
2496 Print information that is specific to the object file format. The
2497 argument @var{options} is a comma separated list that depends on the
2498 format (the lists of options is displayed with the help).
2500 For XCOFF, the available options are:
2516 Not all object formats support this option. In particular the ELF
2517 format does not use it.
2521 @cindex relocation entries, in object file
2522 Print the relocation entries of the file. If used with @option{-d} or
2523 @option{-D}, the relocations are printed interspersed with the
2527 @itemx --dynamic-reloc
2528 @cindex dynamic relocation entries, in object file
2529 Print the dynamic relocation entries of the file. This is only
2530 meaningful for dynamic objects, such as certain types of shared
2531 libraries. As for @option{-r}, if used with @option{-d} or
2532 @option{-D}, the relocations are printed interspersed with the
2536 @itemx --full-contents
2537 @cindex sections, full contents
2538 @cindex object file sections
2539 Display the full contents of any sections requested. By default all
2540 non-empty sections are displayed.
2544 @cindex source disassembly
2545 @cindex disassembly, with source
2546 Display source code intermixed with disassembly, if possible. Implies
2549 @item --prefix=@var{prefix}
2550 @cindex Add prefix to absolute paths
2551 Specify @var{prefix} to add to the absolute paths when used with
2554 @item --prefix-strip=@var{level}
2555 @cindex Strip absolute paths
2556 Indicate how many initial directory names to strip off the hardwired
2557 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2559 @item --show-raw-insn
2560 When disassembling instructions, print the instruction in hex as well as
2561 in symbolic form. This is the default except when
2562 @option{--prefix-addresses} is used.
2564 @item --no-show-raw-insn
2565 When disassembling instructions, do not print the instruction bytes.
2566 This is the default when @option{--prefix-addresses} is used.
2568 @item --insn-width=@var{width}
2569 @cindex Instruction width
2570 Display @var{width} bytes on a single line when disassembling
2573 @item -W[lLiaprmfFsoRtUuTgAckK]
2574 @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]
2575 @include debug.options.texi
2578 Enable additional checks for consistency of Dwarf information.
2584 @cindex debug symbols
2585 @cindex ELF object file format
2586 Display the full contents of any sections requested. Display the
2587 contents of the .stab and .stab.index and .stab.excl sections from an
2588 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2589 @code{.stab} debugging symbol-table entries are carried in an ELF
2590 section. In most other file formats, debugging symbol-table entries are
2591 interleaved with linkage symbols, and are visible in the @option{--syms}
2594 @item --start-address=@var{address}
2595 @cindex start-address
2596 Start displaying data at the specified address. This affects the output
2597 of the @option{-d}, @option{-r} and @option{-s} options.
2599 @item --stop-address=@var{address}
2600 @cindex stop-address
2601 Stop displaying data at the specified address. This affects the output
2602 of the @option{-d}, @option{-r} and @option{-s} options.
2606 @cindex symbol table entries, printing
2607 Print the symbol table entries of the file.
2608 This is similar to the information provided by the @samp{nm} program,
2609 although the display format is different. The format of the output
2610 depends upon the format of the file being dumped, but there are two main
2611 types. One looks like this:
2614 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2615 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2618 where the number inside the square brackets is the number of the entry
2619 in the symbol table, the @var{sec} number is the section number, the
2620 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2621 symbol's type, the @var{scl} number is the symbol's storage class and
2622 the @var{nx} value is the number of auxilary entries associated with
2623 the symbol. The last two fields are the symbol's value and its name.
2625 The other common output format, usually seen with ELF based files,
2629 00000000 l d .bss 00000000 .bss
2630 00000000 g .text 00000000 fred
2633 Here the first number is the symbol's value (sometimes refered to as
2634 its address). The next field is actually a set of characters and
2635 spaces indicating the flag bits that are set on the symbol. These
2636 characters are described below. Next is the section with which the
2637 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2638 not connected with any section), or @emph{*UND*} if the section is
2639 referenced in the file being dumped, but not defined there.
2641 After the section name comes another field, a number, which for common
2642 symbols is the alignment and for other symbol is the size. Finally
2643 the symbol's name is displayed.
2645 The flag characters are divided into 7 groups as follows:
2651 The symbol is a local (l), global (g), unique global (u), neither
2652 global nor local (a space) or both global and local (!). A
2653 symbol can be neither local or global for a variety of reasons, e.g.,
2654 because it is used for debugging, but it is probably an indication of
2655 a bug if it is ever both local and global. Unique global symbols are
2656 a GNU extension to the standard set of ELF symbol bindings. For such
2657 a symbol the dynamic linker will make sure that in the entire process
2658 there is just one symbol with this name and type in use.
2661 The symbol is weak (w) or strong (a space).
2664 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2667 The symbol is a warning (W) or a normal symbol (a space). A warning
2668 symbol's name is a message to be displayed if the symbol following the
2669 warning symbol is ever referenced.
2673 The symbol is an indirect reference to another symbol (I), a function
2674 to be evaluated during reloc processing (i) or a normal symbol (a
2679 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2680 normal symbol (a space).
2685 The symbol is the name of a function (F) or a file (f) or an object
2686 (O) or just a normal symbol (a space).
2690 @itemx --dynamic-syms
2691 @cindex dynamic symbol table entries, printing
2692 Print the dynamic symbol table entries of the file. This is only
2693 meaningful for dynamic objects, such as certain types of shared
2694 libraries. This is similar to the information provided by the @samp{nm}
2695 program when given the @option{-D} (@option{--dynamic}) option.
2697 The output format is similar to that produced by the @option{--syms}
2698 option, except that an extra field is inserted before the symbol's
2699 name, giving the version information associated with the symbol.
2700 If the version is the default version to be used when resolving
2701 unversioned references to the symbol then it's displayed as is,
2702 otherwise it's put into parentheses.
2704 @item --special-syms
2705 When displaying symbols include those which the target considers to be
2706 special in some way and which would not normally be of interest to the
2711 Print the version number of @command{objdump} and exit.
2714 @itemx --all-headers
2715 @cindex all header information, object file
2716 @cindex header information, all
2717 Display all available header information, including the symbol table and
2718 relocation entries. Using @option{-x} is equivalent to specifying all of
2719 @option{-a -f -h -p -r -t}.
2723 @cindex wide output, printing
2724 Format some lines for output devices that have more than 80 columns.
2725 Also do not truncate symbol names when they are displayed.
2728 @itemx --disassemble-zeroes
2729 Normally the disassembly output will skip blocks of zeroes. This
2730 option directs the disassembler to disassemble those blocks, just like
2737 @c man begin SEEALSO objdump
2738 nm(1), readelf(1), and the Info entries for @file{binutils}.
2746 @cindex archive contents
2747 @cindex symbol index
2749 @c man title ranlib generate index to archive.
2752 @c man begin SYNOPSIS ranlib
2753 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2757 @c man begin DESCRIPTION ranlib
2759 @command{ranlib} generates an index to the contents of an archive and
2760 stores it in the archive. The index lists each symbol defined by a
2761 member of an archive that is a relocatable object file.
2763 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2765 An archive with such an index speeds up linking to the library and
2766 allows routines in the library to call each other without regard to
2767 their placement in the archive.
2769 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2770 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2775 @c man begin OPTIONS ranlib
2781 Show usage information for @command{ranlib}.
2786 Show the version number of @command{ranlib}.
2789 @cindex deterministic archives
2790 @kindex --enable-deterministic-archives
2791 Operate in @emph{deterministic} mode. The symbol map archive member's
2792 header will show zero for the UID, GID, and timestamp. When this
2793 option is used, multiple runs will produce identical output files.
2795 If @file{binutils} was configured with
2796 @option{--enable-deterministic-archives}, then this mode is on by
2797 default. It can be disabled with the @samp{-U} option, described
2801 Update the timestamp of the symbol map of an archive.
2804 @cindex deterministic archives
2805 @kindex --enable-deterministic-archives
2806 Do @emph{not} operate in @emph{deterministic} mode. This is the
2807 inverse of the @samp{-D} option, above: the archive index will get
2808 actual UID, GID, timestamp, and file mode values.
2810 If @file{binutils} was configured @emph{without}
2811 @option{--enable-deterministic-archives}, then this mode is on by
2819 @c man begin SEEALSO ranlib
2820 ar(1), nm(1), and the Info entries for @file{binutils}.
2828 @cindex section sizes
2830 @c man title size list section sizes and total size.
2833 @c man begin SYNOPSIS size
2834 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2836 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2838 [@option{-t}|@option{--totals}]
2839 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2840 [@var{objfile}@dots{}]
2844 @c man begin DESCRIPTION size
2846 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2847 size---for each of the object or archive files @var{objfile} in its
2848 argument list. By default, one line of output is generated for each
2849 object file or each module in an archive.
2851 @var{objfile}@dots{} are the object files to be examined.
2852 If none are specified, the file @code{a.out} will be used.
2856 @c man begin OPTIONS size
2858 The command-line options have the following meanings:
2863 @itemx --format=@var{compatibility}
2864 @cindex @command{size} display format
2865 Using one of these options, you can choose whether the output from @sc{gnu}
2866 @command{size} resembles output from System V @command{size} (using @option{-A},
2867 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2868 @option{--format=berkeley}). The default is the one-line format similar to
2870 @c Bonus for doc-source readers: you can also say --format=strange (or
2871 @c anything else that starts with 's') for sysv, and --format=boring (or
2872 @c anything else that starts with 'b') for Berkeley.
2874 Here is an example of the Berkeley (default) format of output from
2877 $ size --format=Berkeley ranlib size
2878 text data bss dec hex filename
2879 294880 81920 11592 388392 5ed28 ranlib
2880 294880 81920 11888 388688 5ee50 size
2884 This is the same data, but displayed closer to System V conventions:
2887 $ size --format=SysV ranlib size
2905 Show a summary of acceptable arguments and options.
2910 @itemx --radix=@var{number}
2911 @cindex @command{size} number format
2912 @cindex radix for section sizes
2913 Using one of these options, you can control whether the size of each
2914 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2915 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2916 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2917 values (8, 10, 16) are supported. The total size is always given in two
2918 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2919 octal and hexadecimal if you're using @option{-o}.
2922 Print total size of common symbols in each file. When using Berkeley
2923 format these are included in the bss size.
2927 Show totals of all objects listed (Berkeley format listing mode only).
2929 @item --target=@var{bfdname}
2930 @cindex object code format
2931 Specify that the object-code format for @var{objfile} is
2932 @var{bfdname}. This option may not be necessary; @command{size} can
2933 automatically recognize many formats.
2934 @xref{Target Selection}, for more information.
2938 Display the version number of @command{size}.
2944 @c man begin SEEALSO size
2945 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2952 @cindex listings strings
2953 @cindex printing strings
2954 @cindex strings, printing
2956 @c man title strings print the strings of printable characters in files.
2959 @c man begin SYNOPSIS strings
2960 strings [@option{-afovV}] [@option{-}@var{min-len}]
2961 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2962 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2963 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2964 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2965 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2966 [@option{-w}] [@option{--include-all-whitespace}]
2967 [@option{-s}] [@option{--output-separator}@var{sep_string}]
2968 [@option{--help}] [@option{--version}] @var{file}@dots{}
2972 @c man begin DESCRIPTION strings
2974 For each @var{file} given, @sc{gnu} @command{strings} prints the
2975 printable character sequences that are at least 4 characters long (or
2976 the number given with the options below) and are followed by an
2977 unprintable character.
2979 Depending upon how the strings program was configured it will default
2980 to either displaying all the printable sequences that it can find in
2981 each file, or only those sequences that are in loadable, initialized
2982 data sections. If the file type in unrecognizable, or if strings is
2983 reading from stdin then it will always display all of the printable
2984 sequences that it can find.
2986 For backwards compatibility any file that occurs after a command-line
2987 option of just @option{-} will also be scanned in full, regardless of
2988 the presence of any @option{-d} option.
2990 @command{strings} is mainly useful for determining the contents of
2995 @c man begin OPTIONS strings
3001 Scan the whole file, regardless of what sections it contains or
3002 whether those sections are loaded or initialized. Normally this is
3003 the default behaviour, but strings can be configured so that the
3004 @option{-d} is the default instead.
3006 The @option{-} option is position dependent and forces strings to
3007 perform full scans of any file that is mentioned after the @option{-}
3008 on the command line, even if the @option{-d} option has been
3013 Only print strings from initialized, loaded data sections in the
3014 file. This may reduce the amount of garbage in the output, but it
3015 also exposes the strings program to any security flaws that may be
3016 present in the BFD library used to scan and load sections. Strings
3017 can be configured so that this option is the default behaviour. In
3018 such cases the @option{-a} option can be used to avoid using the BFD
3019 library and instead just print all of the strings found in the file.
3022 @itemx --print-file-name
3023 Print the name of the file before each string.
3026 Print a summary of the program usage on the standard output and exit.
3028 @item -@var{min-len}
3029 @itemx -n @var{min-len}
3030 @itemx --bytes=@var{min-len}
3031 Print sequences of characters that are at least @var{min-len} characters
3032 long, instead of the default 4.
3035 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3036 act like @samp{-t d} instead. Since we can not be compatible with both
3037 ways, we simply chose one.
3039 @item -t @var{radix}
3040 @itemx --radix=@var{radix}
3041 Print the offset within the file before each string. The single
3042 character argument specifies the radix of the offset---@samp{o} for
3043 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3045 @item -e @var{encoding}
3046 @itemx --encoding=@var{encoding}
3047 Select the character encoding of the strings that are to be found.
3048 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3049 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3050 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3051 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3052 littleendian. Useful for finding wide character strings. (@samp{l}
3053 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3055 @item -T @var{bfdname}
3056 @itemx --target=@var{bfdname}
3057 @cindex object code format
3058 Specify an object code format other than your system's default format.
3059 @xref{Target Selection}, for more information.
3064 Print the program version number on the standard output and exit.
3067 @itemx --include-all-whitespace
3068 By default tab and space characters are included in the strings that
3069 are displayed, but other whitespace characters, such a newlines and
3070 carriage returns, are not. The @option{-w} option changes this so
3071 that all whitespace characters are considered to be part of a string.
3074 @itemx --output-separator
3075 By default, output strings are delimited by a new-line. This option
3076 allows you to supply any string to be used as the output record
3077 separator. Useful with --include-all-whitespace where strings
3078 may contain new-lines internally.
3084 @c man begin SEEALSO strings
3085 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3086 and the Info entries for @file{binutils}.
3094 @cindex removing symbols
3095 @cindex discarding symbols
3096 @cindex symbols, discarding
3098 @c man title strip Discard symbols from object files.
3101 @c man begin SYNOPSIS strip
3102 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3103 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3104 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3105 [@option{-s}|@option{--strip-all}]
3106 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3107 [@option{--strip-dwo}]
3108 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3109 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3110 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3111 [@option{-w}|@option{--wildcard}]
3112 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3113 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3114 [@option{--remove-relocations=}@var{sectionpattern}]
3115 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3116 [@option{-D}|@option{--enable-deterministic-archives}]
3117 [@option{-U}|@option{--disable-deterministic-archives}]
3118 [@option{--keep-file-symbols}]
3119 [@option{--only-keep-debug}]
3120 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3121 [@option{--help}] [@option{--info}]
3122 @var{objfile}@dots{}
3126 @c man begin DESCRIPTION strip
3128 @sc{gnu} @command{strip} discards all symbols from object files
3129 @var{objfile}. The list of object files may include archives.
3130 At least one object file must be given.
3132 @command{strip} modifies the files named in its argument,
3133 rather than writing modified copies under different names.
3137 @c man begin OPTIONS strip
3140 @item -F @var{bfdname}
3141 @itemx --target=@var{bfdname}
3142 Treat the original @var{objfile} as a file with the object
3143 code format @var{bfdname}, and rewrite it in the same format.
3144 @xref{Target Selection}, for more information.
3147 Show a summary of the options to @command{strip} and exit.
3150 Display a list showing all architectures and object formats available.
3152 @item -I @var{bfdname}
3153 @itemx --input-target=@var{bfdname}
3154 Treat the original @var{objfile} as a file with the object
3155 code format @var{bfdname}.
3156 @xref{Target Selection}, for more information.
3158 @item -O @var{bfdname}
3159 @itemx --output-target=@var{bfdname}
3160 Replace @var{objfile} with a file in the output format @var{bfdname}.
3161 @xref{Target Selection}, for more information.
3163 @item -R @var{sectionname}
3164 @itemx --remove-section=@var{sectionname}
3165 Remove any section named @var{sectionname} from the output file, in
3166 addition to whatever sections would otherwise be removed. This
3167 option may be given more than once. Note that using this option
3168 inappropriately may make the output file unusable. The wildcard
3169 character @samp{*} may be given at the end of @var{sectionname}. If
3170 so, then any section starting with @var{sectionname} will be removed.
3172 If the first character of @var{sectionpattern} is the exclamation
3173 point (!) then matching sections will not be removed even if an
3174 earlier use of @option{--remove-section} on the same command line
3175 would otherwise remove it. For example:
3178 --remove-section=.text.* --remove-section=!.text.foo
3181 will remove all sections matching the pattern '.text.*', but will not
3182 remove the section '.text.foo'.
3184 @item --remove-relocations=@var{sectionpattern}
3185 Remove relocations from the output file for any section matching
3186 @var{sectionpattern}. This option may be given more than once. Note
3187 that using this option inappropriately may make the output file
3188 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3192 --remove-relocations=.text.*
3195 will remove the relocations for all sections matching the patter
3198 If the first character of @var{sectionpattern} is the exclamation
3199 point (!) then matching sections will not have their relocation
3200 removed even if an earlier use of @option{--remove-relocations} on the
3201 same command line would otherwise cause the relocations to be removed.
3205 --remove-relocations=.text.* --remove-relocations=!.text.foo
3208 will remove all relocations for sections matching the pattern
3209 '.text.*', but will not remove relocations for the section
3219 @itemx --strip-debug
3220 Remove debugging symbols only.
3223 Remove the contents of all DWARF .dwo sections, leaving the
3224 remaining debugging sections and all symbols intact.
3225 See the description of this option in the @command{objcopy} section
3226 for more information.
3228 @item --strip-unneeded
3229 Remove all symbols that are not needed for relocation processing.
3231 @item -K @var{symbolname}
3232 @itemx --keep-symbol=@var{symbolname}
3233 When stripping symbols, keep symbol @var{symbolname} even if it would
3234 normally be stripped. This option may be given more than once.
3237 @itemx --merge-notes
3238 @itemx --no-merge-notes
3239 For ELF files, attempt (or do not attempt) to reduce the size of any
3240 SHT_NOTE type sections by removing duplicate notes. The default is to
3241 attempt this reduction.
3243 @item -N @var{symbolname}
3244 @itemx --strip-symbol=@var{symbolname}
3245 Remove symbol @var{symbolname} from the source file. This option may be
3246 given more than once, and may be combined with strip options other than
3250 Put the stripped output in @var{file}, rather than replacing the
3251 existing file. When this argument is used, only one @var{objfile}
3252 argument may be specified.
3255 @itemx --preserve-dates
3256 Preserve the access and modification dates of the file.
3259 @itemx --enable-deterministic-archives
3260 @cindex deterministic archives
3261 @kindex --enable-deterministic-archives
3262 Operate in @emph{deterministic} mode. When copying archive members
3263 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3264 and use consistent file modes for all files.
3266 If @file{binutils} was configured with
3267 @option{--enable-deterministic-archives}, then this mode is on by default.
3268 It can be disabled with the @samp{-U} option, below.
3271 @itemx --disable-deterministic-archives
3272 @cindex deterministic archives
3273 @kindex --enable-deterministic-archives
3274 Do @emph{not} operate in @emph{deterministic} mode. This is the
3275 inverse of the @option{-D} option, above: when copying archive members
3276 and writing the archive index, use their actual UID, GID, timestamp,
3277 and file mode values.
3279 This is the default unless @file{binutils} was configured with
3280 @option{--enable-deterministic-archives}.
3284 Permit regular expressions in @var{symbolname}s used in other command
3285 line options. The question mark (?), asterisk (*), backslash (\) and
3286 square brackets ([]) operators can be used anywhere in the symbol
3287 name. If the first character of the symbol name is the exclamation
3288 point (!) then the sense of the switch is reversed for that symbol.
3295 would cause strip to only keep symbols that start with the letters
3296 ``fo'', but to discard the symbol ``foo''.
3299 @itemx --discard-all
3300 Remove non-global symbols.
3303 @itemx --discard-locals
3304 Remove compiler-generated local symbols.
3305 (These usually start with @samp{L} or @samp{.}.)
3307 @item --keep-file-symbols
3308 When stripping a file, perhaps with @option{--strip-debug} or
3309 @option{--strip-unneeded}, retain any symbols specifying source file names,
3310 which would otherwise get stripped.
3312 @item --only-keep-debug
3313 Strip a file, emptying the contents of any sections that would not be
3314 stripped by @option{--strip-debug} and leaving the debugging sections
3315 intact. In ELF files, this preserves all the note sections in the
3318 Note - the section headers of the stripped sections are preserved,
3319 including their sizes, but the contents of the section are discarded.
3320 The section headers are preserved so that other tools can match up the
3321 debuginfo file with the real executable, even if that executable has
3322 been relocated to a different address space.
3324 The intention is that this option will be used in conjunction with
3325 @option{--add-gnu-debuglink} to create a two part executable. One a
3326 stripped binary which will occupy less space in RAM and in a
3327 distribution and the second a debugging information file which is only
3328 needed if debugging abilities are required. The suggested procedure
3329 to create these files is as follows:
3332 @item Link the executable as normal. Assuming that it is called
3334 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3335 create a file containing the debugging info.
3336 @item Run @code{objcopy --strip-debug foo} to create a
3337 stripped executable.
3338 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3339 to add a link to the debugging info into the stripped executable.
3342 Note---the choice of @code{.dbg} as an extension for the debug info
3343 file is arbitrary. Also the @code{--only-keep-debug} step is
3344 optional. You could instead do this:
3347 @item Link the executable as normal.
3348 @item Copy @code{foo} to @code{foo.full}
3349 @item Run @code{strip --strip-debug foo}
3350 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3353 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3354 full executable. It does not have to be a file created by the
3355 @option{--only-keep-debug} switch.
3357 Note---this switch is only intended for use on fully linked files. It
3358 does not make sense to use it on object files where the debugging
3359 information may be incomplete. Besides the gnu_debuglink feature
3360 currently only supports the presence of one filename containing
3361 debugging information, not multiple filenames on a one-per-object-file
3366 Show the version number for @command{strip}.
3370 Verbose output: list all object files modified. In the case of
3371 archives, @samp{strip -v} lists all members of the archive.
3377 @c man begin SEEALSO strip
3378 the Info entries for @file{binutils}.
3382 @node c++filt, addr2line, strip, Top
3386 @cindex demangling C++ symbols
3388 @c man title cxxfilt Demangle C++ and Java symbols.
3391 @c man begin SYNOPSIS cxxfilt
3392 c++filt [@option{-_}|@option{--strip-underscore}]
3393 [@option{-n}|@option{--no-strip-underscore}]
3394 [@option{-p}|@option{--no-params}]
3395 [@option{-t}|@option{--types}]
3396 [@option{-i}|@option{--no-verbose}]
3397 [@option{-s} @var{format}|@option{--format=}@var{format}]
3398 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3402 @c man begin DESCRIPTION cxxfilt
3405 The C++ and Java languages provide function overloading, which means
3406 that you can write many functions with the same name, providing that
3407 each function takes parameters of different types. In order to be
3408 able to distinguish these similarly named functions C++ and Java
3409 encode them into a low-level assembler name which uniquely identifies
3410 each different version. This process is known as @dfn{mangling}. The
3412 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3413 MS-DOS this program is named @command{CXXFILT}.}
3414 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3415 names into user-level names so that they can be read.
3417 Every alphanumeric word (consisting of letters, digits, underscores,
3418 dollars, or periods) seen in the input is a potential mangled name.
3419 If the name decodes into a C++ name, the C++ name replaces the
3420 low-level name in the output, otherwise the original word is output.
3421 In this way you can pass an entire assembler source file, containing
3422 mangled names, through @command{c++filt} and see the same source file
3423 containing demangled names.
3425 You can also use @command{c++filt} to decipher individual symbols by
3426 passing them on the command line:
3429 c++filt @var{symbol}
3432 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3433 names from the standard input instead. All the results are printed on
3434 the standard output. The difference between reading names from the
3435 command line versus reading names from the standard input is that
3436 command-line arguments are expected to be just mangled names and no
3437 checking is performed to separate them from surrounding text. Thus
3444 will work and demangle the name to ``f()'' whereas:
3450 will not work. (Note the extra comma at the end of the mangled
3451 name which makes it invalid). This command however will work:
3454 echo _Z1fv, | c++filt -n
3457 and will display ``f(),'', i.e., the demangled name followed by a
3458 trailing comma. This behaviour is because when the names are read
3459 from the standard input it is expected that they might be part of an
3460 assembler source file where there might be extra, extraneous
3461 characters trailing after a mangled name. For example:
3464 .type _Z1fv, @@function
3469 @c man begin OPTIONS cxxfilt
3473 @itemx --strip-underscore
3474 On some systems, both the C and C++ compilers put an underscore in front
3475 of every name. For example, the C name @code{foo} gets the low-level
3476 name @code{_foo}. This option removes the initial underscore. Whether
3477 @command{c++filt} removes the underscore by default is target dependent.
3480 @itemx --no-strip-underscore
3481 Do not remove the initial underscore.
3485 When demangling the name of a function, do not display the types of
3486 the function's parameters.
3490 Attempt to demangle types as well as function names. This is disabled
3491 by default since mangled types are normally only used internally in
3492 the compiler, and they can be confused with non-mangled names. For example,
3493 a function called ``a'' treated as a mangled type name would be
3494 demangled to ``signed char''.
3498 Do not include implementation details (if any) in the demangled
3501 @item -s @var{format}
3502 @itemx --format=@var{format}
3503 @command{c++filt} can decode various methods of mangling, used by
3504 different compilers. The argument to this option selects which
3509 Automatic selection based on executable (the default method)
3511 the one used by the @sc{gnu} C++ compiler (g++)
3513 the one used by the Lucid compiler (lcc)
3515 the one specified by the C++ Annotated Reference Manual
3517 the one used by the HP compiler (aCC)
3519 the one used by the EDG compiler
3521 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3523 the one used by the @sc{gnu} Java compiler (gcj)
3525 the one used by the @sc{gnu} Ada compiler (GNAT).
3529 Print a summary of the options to @command{c++filt} and exit.
3532 Print the version number of @command{c++filt} and exit.
3538 @c man begin SEEALSO cxxfilt
3539 the Info entries for @file{binutils}.
3544 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3545 user interface are subject to change in future releases. In particular,
3546 a command-line option may be required in the future to decode a name
3547 passed as an argument on the command line; in other words,
3550 c++filt @var{symbol}
3554 may in a future release become
3557 c++filt @var{option} @var{symbol}
3565 @cindex address to file name and line number
3567 @c man title addr2line convert addresses into file names and line numbers.
3570 @c man begin SYNOPSIS addr2line
3571 addr2line [@option{-a}|@option{--addresses}]
3572 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3573 [@option{-C}|@option{--demangle}[=@var{style}]]
3574 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3575 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3576 [@option{-i}|@option{--inlines}]
3577 [@option{-p}|@option{--pretty-print}]
3578 [@option{-j}|@option{--section=}@var{name}]
3579 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3584 @c man begin DESCRIPTION addr2line
3586 @command{addr2line} translates addresses into file names and line numbers.
3587 Given an address in an executable or an offset in a section of a relocatable
3588 object, it uses the debugging information to figure out which file name and
3589 line number are associated with it.
3591 The executable or relocatable object to use is specified with the @option{-e}
3592 option. The default is the file @file{a.out}. The section in the relocatable
3593 object to use is specified with the @option{-j} option.
3595 @command{addr2line} has two modes of operation.
3597 In the first, hexadecimal addresses are specified on the command line,
3598 and @command{addr2line} displays the file name and line number for each
3601 In the second, @command{addr2line} reads hexadecimal addresses from
3602 standard input, and prints the file name and line number for each
3603 address on standard output. In this mode, @command{addr2line} may be used
3604 in a pipe to convert dynamically chosen addresses.
3606 The format of the output is @samp{FILENAME:LINENO}. By default
3607 each input address generates one line of output.
3609 Two options can generate additional lines before each
3610 @samp{FILENAME:LINENO} line (in that order).
3612 If the @option{-a} option is used then a line with the input address
3615 If the @option{-f} option is used, then a line with the
3616 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3617 containing the address.
3619 One option can generate additional lines after the
3620 @samp{FILENAME:LINENO} line.
3622 If the @option{-i} option is used and the code at the given address is
3623 present there because of inlining by the compiler then additional
3624 lines are displayed afterwards. One or two extra lines (if the
3625 @option{-f} option is used) are displayed for each inlined function.
3627 Alternatively if the @option{-p} option is used then each input
3628 address generates a single, long, output line containing the address,
3629 the function name, the file name and the line number. If the
3630 @option{-i} option has also been used then any inlined functions will
3631 be displayed in the same manner, but on separate lines, and prefixed
3632 by the text @samp{(inlined by)}.
3634 If the file name or function name can not be determined,
3635 @command{addr2line} will print two question marks in their place. If the
3636 line number can not be determined, @command{addr2line} will print 0.
3640 @c man begin OPTIONS addr2line
3642 The long and short forms of options, shown here as alternatives, are
3648 Display the address before the function name, file and line number
3649 information. The address is printed with a @samp{0x} prefix to easily
3652 @item -b @var{bfdname}
3653 @itemx --target=@var{bfdname}
3654 @cindex object code format
3655 Specify that the object-code format for the object files is
3659 @itemx --demangle[=@var{style}]
3660 @cindex demangling in objdump
3661 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3662 Besides removing any initial underscore prepended by the system, this
3663 makes C++ function names readable. Different compilers have different
3664 mangling styles. The optional demangling style argument can be used to
3665 choose an appropriate demangling style for your compiler. @xref{c++filt},
3666 for more information on demangling.
3668 @item -e @var{filename}
3669 @itemx --exe=@var{filename}
3670 Specify the name of the executable for which addresses should be
3671 translated. The default file is @file{a.out}.
3675 Display function names as well as file and line number information.
3679 Display only the base of each file name.
3683 If the address belongs to a function that was inlined, the source
3684 information for all enclosing scopes back to the first non-inlined
3685 function will also be printed. For example, if @code{main} inlines
3686 @code{callee1} which inlines @code{callee2}, and address is from
3687 @code{callee2}, the source information for @code{callee1} and @code{main}
3688 will also be printed.
3692 Read offsets relative to the specified section instead of absolute addresses.
3695 @itemx --pretty-print
3696 Make the output more human friendly: each location are printed on one line.
3697 If option @option{-i} is specified, lines for all enclosing scopes are
3698 prefixed with @samp{(inlined by)}.
3704 @c man begin SEEALSO addr2line
3705 Info entries for @file{binutils}.
3712 @command{windmc} may be used to generator Windows message resources.
3715 @emph{Warning:} @command{windmc} is not always built as part of the binary
3716 utilities, since it is only useful for Windows targets.
3719 @c man title windmc generates Windows message resources.
3722 @c man begin SYNOPSIS windmc
3723 windmc [options] input-file
3727 @c man begin DESCRIPTION windmc
3729 @command{windmc} reads message definitions from an input file (.mc) and
3730 translate them into a set of output files. The output files may be of
3735 A C header file containing the message definitions.
3738 A resource file compilable by the @command{windres} tool.
3741 One or more binary files containing the resource data for a specific
3745 A C include file that maps message id's to their symbolic name.
3748 The exact description of these different formats is available in
3749 documentation from Microsoft.
3751 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3752 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3753 Windows Message Compiler.
3757 @c man begin OPTIONS windmc
3762 Specifies that the input file specified is ASCII. This is the default
3767 Specifies that messages in the output @code{bin} files should be in ASCII
3772 Specifies that @code{bin} filenames should have to be prefixed by the
3773 basename of the source file.
3777 Sets the customer bit in all message id's.
3779 @item -C @var{codepage}
3780 @itemx --codepage_in @var{codepage}
3781 Sets the default codepage to be used to convert input file to UTF16. The
3782 default is ocdepage 1252.
3785 @itemx --decimal_values
3786 Outputs the constants in the header file in decimal. Default is using
3790 @itemx --extension @var{ext}
3791 The extension for the header file. The default is .h extension.
3793 @item -F @var{target}
3794 @itemx --target @var{target}
3795 Specify the BFD format to use for a bin file as output. This
3796 is a BFD target name; you can use the @option{--help} option to see a list
3797 of supported targets. Normally @command{windmc} will use the default
3798 format, which is the first one listed by the @option{--help} option.
3800 @ref{Target Selection}.
3804 @itemx --headerdir @var{path}
3805 The target directory of the generated header file. The default is the
3810 Displays a list of command-line options and then exits.
3812 @item -m @var{characters}
3813 @itemx --maxlength @var{characters}
3814 Instructs @command{windmc} to generate a warning if the length
3815 of any message exceeds the number specified.
3818 @itemx --nullterminate
3819 Terminate message text in @code{bin} files by zero. By default they are
3820 terminated by CR/LF.
3823 @itemx --hresult_use
3824 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3825 file, using HRESULT definitions. Status codes are used if the flag is not
3828 @item -O @var{codepage}
3829 @itemx --codepage_out @var{codepage}
3830 Sets the default codepage to be used to output text files. The default
3834 @itemx --rcdir @var{path}
3835 The target directory for the generated @code{rc} script and the generated
3836 @code{bin} files that the resource compiler script includes. The default
3837 is the current directory.
3841 Specifies that the input file is UTF16.
3844 @itemx --unicode_out
3845 Specifies that messages in the output @code{bin} file should be in UTF16
3846 format. This is the default behaviour.
3850 Enable verbose mode.
3854 Prints the version number for @command{windmc}.
3857 @itemx --xdgb @var{path}
3858 The path of the @code{dbg} C include file that maps message id's to the
3859 symbolic name. No such file is generated without specifying the switch.
3865 @c man begin SEEALSO windmc
3866 the Info entries for @file{binutils}.
3873 @command{windres} may be used to manipulate Windows resources.
3876 @emph{Warning:} @command{windres} is not always built as part of the binary
3877 utilities, since it is only useful for Windows targets.
3880 @c man title windres manipulate Windows resources.
3883 @c man begin SYNOPSIS windres
3884 windres [options] [input-file] [output-file]
3888 @c man begin DESCRIPTION windres
3890 @command{windres} reads resources from an input file and copies them into
3891 an output file. Either file may be in one of three formats:
3895 A text format read by the Resource Compiler.
3898 A binary format generated by the Resource Compiler.
3901 A COFF object or executable.
3904 The exact description of these different formats is available in
3905 documentation from Microsoft.
3907 When @command{windres} converts from the @code{rc} format to the @code{res}
3908 format, it is acting like the Windows Resource Compiler. When
3909 @command{windres} converts from the @code{res} format to the @code{coff}
3910 format, it is acting like the Windows @code{CVTRES} program.
3912 When @command{windres} generates an @code{rc} file, the output is similar
3913 but not identical to the format expected for the input. When an input
3914 @code{rc} file refers to an external filename, an output @code{rc} file
3915 will instead include the file contents.
3917 If the input or output format is not specified, @command{windres} will
3918 guess based on the file name, or, for the input file, the file contents.
3919 A file with an extension of @file{.rc} will be treated as an @code{rc}
3920 file, a file with an extension of @file{.res} will be treated as a
3921 @code{res} file, and a file with an extension of @file{.o} or
3922 @file{.exe} will be treated as a @code{coff} file.
3924 If no output file is specified, @command{windres} will print the resources
3925 in @code{rc} format to standard output.
3927 The normal use is for you to write an @code{rc} file, use @command{windres}
3928 to convert it to a COFF object file, and then link the COFF file into
3929 your application. This will make the resources described in the
3930 @code{rc} file available to Windows.
3934 @c man begin OPTIONS windres
3937 @item -i @var{filename}
3938 @itemx --input @var{filename}
3939 The name of the input file. If this option is not used, then
3940 @command{windres} will use the first non-option argument as the input file
3941 name. If there are no non-option arguments, then @command{windres} will
3942 read from standard input. @command{windres} can not read a COFF file from
3945 @item -o @var{filename}
3946 @itemx --output @var{filename}
3947 The name of the output file. If this option is not used, then
3948 @command{windres} will use the first non-option argument, after any used
3949 for the input file name, as the output file name. If there is no
3950 non-option argument, then @command{windres} will write to standard output.
3951 @command{windres} can not write a COFF file to standard output. Note,
3952 for compatibility with @command{rc} the option @option{-fo} is also
3953 accepted, but its use is not recommended.
3955 @item -J @var{format}
3956 @itemx --input-format @var{format}
3957 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3958 @samp{coff}. If no input format is specified, @command{windres} will
3959 guess, as described above.
3961 @item -O @var{format}
3962 @itemx --output-format @var{format}
3963 The output format to generate. @var{format} may be @samp{res},
3964 @samp{rc}, or @samp{coff}. If no output format is specified,
3965 @command{windres} will guess, as described above.
3967 @item -F @var{target}
3968 @itemx --target @var{target}
3969 Specify the BFD format to use for a COFF file as input or output. This
3970 is a BFD target name; you can use the @option{--help} option to see a list
3971 of supported targets. Normally @command{windres} will use the default
3972 format, which is the first one listed by the @option{--help} option.
3974 @ref{Target Selection}.
3977 @item --preprocessor @var{program}
3978 When @command{windres} reads an @code{rc} file, it runs it through the C
3979 preprocessor first. This option may be used to specify the preprocessor
3980 to use, including any leading arguments. The default preprocessor
3981 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3983 @item --preprocessor-arg @var{option}
3984 When @command{windres} reads an @code{rc} file, it runs it through
3985 the C preprocessor first. This option may be used to specify additional
3986 text to be passed to preprocessor on its command line.
3987 This option can be used multiple times to add multiple options to the
3988 preprocessor command line.
3990 @item -I @var{directory}
3991 @itemx --include-dir @var{directory}
3992 Specify an include directory to use when reading an @code{rc} file.
3993 @command{windres} will pass this to the preprocessor as an @option{-I}
3994 option. @command{windres} will also search this directory when looking for
3995 files named in the @code{rc} file. If the argument passed to this command
3996 matches any of the supported @var{formats} (as described in the @option{-J}
3997 option), it will issue a deprecation warning, and behave just like the
3998 @option{-J} option. New programs should not use this behaviour. If a
3999 directory happens to match a @var{format}, simple prefix it with @samp{./}
4000 to disable the backward compatibility.
4002 @item -D @var{target}
4003 @itemx --define @var{sym}[=@var{val}]
4004 Specify a @option{-D} option to pass to the preprocessor when reading an
4007 @item -U @var{target}
4008 @itemx --undefine @var{sym}
4009 Specify a @option{-U} option to pass to the preprocessor when reading an
4013 Ignored for compatibility with rc.
4016 Enable verbose mode. This tells you what the preprocessor is if you
4020 @item --codepage @var{val}
4021 Specify the default codepage to use when reading an @code{rc} file.
4022 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4023 codepage code. The valid range is from zero up to 0xffff, but the
4024 validity of the codepage is host and configuration dependent.
4027 @item --language @var{val}
4028 Specify the default language to use when reading an @code{rc} file.
4029 @var{val} should be a hexadecimal language code. The low eight bits are
4030 the language, and the high eight bits are the sublanguage.
4032 @item --use-temp-file
4033 Use a temporary file to instead of using popen to read the output of
4034 the preprocessor. Use this option if the popen implementation is buggy
4035 on the host (eg., certain non-English language versions of Windows 95 and
4036 Windows 98 are known to have buggy popen where the output will instead
4039 @item --no-use-temp-file
4040 Use popen, not a temporary file, to read the output of the preprocessor.
4041 This is the default behaviour.
4045 Prints a usage summary.
4049 Prints the version number for @command{windres}.
4052 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4053 this will turn on parser debugging.
4059 @c man begin SEEALSO windres
4060 the Info entries for @file{binutils}.
4069 @command{dlltool} is used to create the files needed to create dynamic
4070 link libraries (DLLs) on systems which understand PE format image
4071 files such as Windows. A DLL contains an export table which contains
4072 information that the runtime loader needs to resolve references from a
4073 referencing program.
4075 The export table is generated by this program by reading in a
4076 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4077 will be in the DLL. A @file{.o} file can contain information in
4078 special @samp{.drectve} sections with export information.
4081 @emph{Note:} @command{dlltool} is not always built as part of the
4082 binary utilities, since it is only useful for those targets which
4086 @c man title dlltool Create files needed to build and use DLLs.
4089 @c man begin SYNOPSIS dlltool
4090 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4091 [@option{-b}|@option{--base-file} @var{base-file-name}]
4092 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4093 [@option{-z}|@option{--output-def} @var{def-file-name}]
4094 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4095 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4096 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4097 [@option{--exclude-symbols} @var{list}]
4098 [@option{--no-default-excludes}]
4099 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4100 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4101 [@option{-a}|@option{--add-indirect}]
4102 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4103 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4104 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4105 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4106 [@option{--use-nul-prefixed-import-tables}]
4107 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4108 [@option{-i}|@option{--interwork}]
4109 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4110 [@option{-v}|@option{--verbose}]
4111 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4112 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4113 [object-file @dots{}]
4117 @c man begin DESCRIPTION dlltool
4119 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4120 @option{-b} options as well as object files specified on the command
4121 line. It then processes these inputs and if the @option{-e} option has
4122 been specified it creates a exports file. If the @option{-l} option
4123 has been specified it creates a library file and if the @option{-z} option
4124 has been specified it creates a def file. Any or all of the @option{-e},
4125 @option{-l} and @option{-z} options can be present in one invocation of
4128 When creating a DLL, along with the source for the DLL, it is necessary
4129 to have three other files. @command{dlltool} can help with the creation of
4132 The first file is a @file{.def} file which specifies which functions are
4133 exported from the DLL, which functions the DLL imports, and so on. This
4134 is a text file and can be created by hand, or @command{dlltool} can be used
4135 to create it using the @option{-z} option. In this case @command{dlltool}
4136 will scan the object files specified on its command line looking for
4137 those functions which have been specially marked as being exported and
4138 put entries for them in the @file{.def} file it creates.
4140 In order to mark a function as being exported from a DLL, it needs to
4141 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4142 section of the object file. This can be done in C by using the
4146 asm (".section .drectve");
4147 asm (".ascii \"-export:my_func\"");
4149 int my_func (void) @{ @dots{} @}
4152 The second file needed for DLL creation is an exports file. This file
4153 is linked with the object files that make up the body of the DLL and it
4154 handles the interface between the DLL and the outside world. This is a
4155 binary file and it can be created by giving the @option{-e} option to
4156 @command{dlltool} when it is creating or reading in a @file{.def} file.
4158 The third file needed for DLL creation is the library file that programs
4159 will link with in order to access the functions in the DLL (an `import
4160 library'). This file can be created by giving the @option{-l} option to
4161 dlltool when it is creating or reading in a @file{.def} file.
4163 If the @option{-y} option is specified, dlltool generates a delay-import
4164 library that can be used instead of the normal import library to allow
4165 a program to link to the dll only as soon as an imported function is
4166 called for the first time. The resulting executable will need to be
4167 linked to the static delayimp library containing __delayLoadHelper2(),
4168 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4170 @command{dlltool} builds the library file by hand, but it builds the
4171 exports file by creating temporary files containing assembler statements
4172 and then assembling these. The @option{-S} command-line option can be
4173 used to specify the path to the assembler that dlltool will use,
4174 and the @option{-f} option can be used to pass specific flags to that
4175 assembler. The @option{-n} can be used to prevent dlltool from deleting
4176 these temporary assembler files when it is done, and if @option{-n} is
4177 specified twice then this will prevent dlltool from deleting the
4178 temporary object files it used to build the library.
4180 Here is an example of creating a DLL from a source file @samp{dll.c} and
4181 also creating a program (from an object file called @samp{program.o})
4186 dlltool -e exports.o -l dll.lib dll.o
4187 gcc dll.o exports.o -o dll.dll
4188 gcc program.o dll.lib -o program
4192 @command{dlltool} may also be used to query an existing import library
4193 to determine the name of the DLL to which it is associated. See the
4194 description of the @option{-I} or @option{--identify} option.
4198 @c man begin OPTIONS dlltool
4200 The command-line options have the following meanings:
4204 @item -d @var{filename}
4205 @itemx --input-def @var{filename}
4206 @cindex input .def file
4207 Specifies the name of a @file{.def} file to be read in and processed.
4209 @item -b @var{filename}
4210 @itemx --base-file @var{filename}
4212 Specifies the name of a base file to be read in and processed. The
4213 contents of this file will be added to the relocation section in the
4214 exports file generated by dlltool.
4216 @item -e @var{filename}
4217 @itemx --output-exp @var{filename}
4218 Specifies the name of the export file to be created by dlltool.
4220 @item -z @var{filename}
4221 @itemx --output-def @var{filename}
4222 Specifies the name of the @file{.def} file to be created by dlltool.
4224 @item -l @var{filename}
4225 @itemx --output-lib @var{filename}
4226 Specifies the name of the library file to be created by dlltool.
4228 @item -y @var{filename}
4229 @itemx --output-delaylib @var{filename}
4230 Specifies the name of the delay-import library file to be created by dlltool.
4232 @item --export-all-symbols
4233 Treat all global and weak defined symbols found in the input object
4234 files as symbols to be exported. There is a small list of symbols which
4235 are not exported by default; see the @option{--no-default-excludes}
4236 option. You may add to the list of symbols to not export by using the
4237 @option{--exclude-symbols} option.
4239 @item --no-export-all-symbols
4240 Only export symbols explicitly listed in an input @file{.def} file or in
4241 @samp{.drectve} sections in the input object files. This is the default
4242 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4243 attributes in the source code.
4245 @item --exclude-symbols @var{list}
4246 Do not export the symbols in @var{list}. This is a list of symbol names
4247 separated by comma or colon characters. The symbol names should not
4248 contain a leading underscore. This is only meaningful when
4249 @option{--export-all-symbols} is used.
4251 @item --no-default-excludes
4252 When @option{--export-all-symbols} is used, it will by default avoid
4253 exporting certain special symbols. The current list of symbols to avoid
4254 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4255 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4256 to go ahead and export these special symbols. This is only meaningful
4257 when @option{--export-all-symbols} is used.
4260 @itemx --as @var{path}
4261 Specifies the path, including the filename, of the assembler to be used
4262 to create the exports file.
4264 @item -f @var{options}
4265 @itemx --as-flags @var{options}
4266 Specifies any specific command-line options to be passed to the
4267 assembler when building the exports file. This option will work even if
4268 the @option{-S} option is not used. This option only takes one argument,
4269 and if it occurs more than once on the command line, then later
4270 occurrences will override earlier occurrences. So if it is necessary to
4271 pass multiple options to the assembler they should be enclosed in
4275 @itemx --dll-name @var{name}
4276 Specifies the name to be stored in the @file{.def} file as the name of
4277 the DLL when the @option{-e} option is used. If this option is not
4278 present, then the filename given to the @option{-e} option will be
4279 used as the name of the DLL.
4281 @item -m @var{machine}
4282 @itemx -machine @var{machine}
4283 Specifies the type of machine for which the library file should be
4284 built. @command{dlltool} has a built in default type, depending upon how
4285 it was created, but this option can be used to override that. This is
4286 normally only useful when creating DLLs for an ARM processor, when the
4287 contents of the DLL are actually encode using Thumb instructions.
4290 @itemx --add-indirect
4291 Specifies that when @command{dlltool} is creating the exports file it
4292 should add a section which allows the exported functions to be
4293 referenced without using the import library. Whatever the hell that
4297 @itemx --add-underscore
4298 Specifies that when @command{dlltool} is creating the exports file it
4299 should prepend an underscore to the names of @emph{all} exported symbols.
4301 @item --no-leading-underscore
4302 @item --leading-underscore
4303 Specifies whether standard symbol should be forced to be prefixed, or
4306 @item --add-stdcall-underscore
4307 Specifies that when @command{dlltool} is creating the exports file it
4308 should prepend an underscore to the names of exported @emph{stdcall}
4309 functions. Variable names and non-stdcall function names are not modified.
4310 This option is useful when creating GNU-compatible import libs for third
4311 party DLLs that were built with MS-Windows tools.
4315 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4316 of stdcall functions that will be imported from the DLL. This is
4317 useful when creating an import library for a DLL which exports stdcall
4318 functions but without the usual @samp{@@<number>} symbol name suffix.
4320 This does not change the naming of symbols provided by the import library
4321 to programs linked against it, but only the entries in the import table
4322 (ie the .idata section).
4325 @itemx --add-stdcall-alias
4326 Specifies that when @command{dlltool} is creating the exports file it
4327 should add aliases for stdcall symbols without @samp{@@ <number>}
4328 in addition to the symbols with @samp{@@ <number>}.
4331 @itemx --ext-prefix-alias @var{prefix}
4332 Causes @command{dlltool} to create external aliases for all DLL
4333 imports with the specified prefix. The aliases are created for both
4334 external and import symbols with no leading underscore.
4338 Specifies that when @command{dlltool} is creating the exports and library
4339 files it should omit the @code{.idata4} section. This is for compatibility
4340 with certain operating systems.
4342 @item --use-nul-prefixed-import-tables
4343 Specifies that when @command{dlltool} is creating the exports and library
4344 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4345 element. This emulates old gnu import library generation of
4346 @code{dlltool}. By default this option is turned off.
4350 Specifies that when @command{dlltool} is creating the exports and library
4351 files it should omit the @code{.idata5} section. This is for compatibility
4352 with certain operating systems.
4354 @item -I @var{filename}
4355 @itemx --identify @var{filename}
4356 Specifies that @command{dlltool} should inspect the import library
4357 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4358 of the associated DLL(s). This can be performed in addition to any
4359 other operations indicated by the other options and arguments.
4360 @command{dlltool} fails if the import library does not exist or is not
4361 actually an import library. See also @option{--identify-strict}.
4363 @item --identify-strict
4364 Modifies the behavior of the @option{--identify} option, such
4365 that an error is reported if @var{filename} is associated with
4370 Specifies that @command{dlltool} should mark the objects in the library
4371 file and exports file that it produces as supporting interworking
4372 between ARM and Thumb code.
4376 Makes @command{dlltool} preserve the temporary assembler files it used to
4377 create the exports file. If this option is repeated then dlltool will
4378 also preserve the temporary object files it uses to create the library
4381 @item -t @var{prefix}
4382 @itemx --temp-prefix @var{prefix}
4383 Makes @command{dlltool} use @var{prefix} when constructing the names of
4384 temporary assembler and object files. By default, the temp file prefix
4385 is generated from the pid.
4389 Make dlltool describe what it is doing.
4393 Displays a list of command-line options and then exits.
4397 Displays dlltool's version number and then exits.
4404 * def file format:: The format of the dlltool @file{.def} file
4407 @node def file format
4408 @section The format of the @command{dlltool} @file{.def} file
4410 A @file{.def} file contains any number of the following commands:
4414 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4415 The result is going to be named @var{name}@code{.exe}.
4417 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4418 The result is going to be named @var{name}@code{.dll}.
4419 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4420 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4423 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4424 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4425 Declares @var{name1} as an exported symbol from the DLL, with optional
4426 ordinal number @var{integer}, or declares @var{name1} as an alias
4427 (forward) of the function @var{external-name} in the DLL.
4428 If @var{its_name} is specified, this name is used as string in export table.
4430 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4431 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4432 If you want to use LIBRARY as name then you need to quote it.
4434 @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{]} *}
4435 Declares that @var{external-name} or the exported function whose
4436 ordinal number is @var{integer} is to be imported from the file
4437 @var{module-name}. If @var{internal-name} is specified then this is
4438 the name that the imported function will be referred to in the body of
4440 If @var{its_name} is specified, this name is used as string in import table.
4441 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4442 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4443 If you want to use LIBRARY as name then you need to quote it.
4445 @item @code{DESCRIPTION} @var{string}
4446 Puts @var{string} into the output @file{.exp} file in the
4447 @code{.rdata} section.
4449 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4450 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4451 Generates @code{--stack} or @code{--heap}
4452 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4453 section. The linker will see this and act upon it.
4455 @item @code{CODE} @var{attr} @code{+}
4456 @item @code{DATA} @var{attr} @code{+}
4457 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4458 Generates @code{--attr} @var{section-name} @var{attr} in the output
4459 @code{.drectve} section, where @var{attr} is one of @code{READ},
4460 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4461 this and act upon it.
4466 @c man begin SEEALSO dlltool
4467 The Info pages for @file{binutils}.
4474 @cindex ELF file information
4477 @c man title readelf Displays information about ELF files.
4480 @c man begin SYNOPSIS readelf
4481 readelf [@option{-a}|@option{--all}]
4482 [@option{-h}|@option{--file-header}]
4483 [@option{-l}|@option{--program-headers}|@option{--segments}]
4484 [@option{-S}|@option{--section-headers}|@option{--sections}]
4485 [@option{-g}|@option{--section-groups}]
4486 [@option{-t}|@option{--section-details}]
4487 [@option{-e}|@option{--headers}]
4488 [@option{-s}|@option{--syms}|@option{--symbols}]
4489 [@option{--dyn-syms}]
4490 [@option{-n}|@option{--notes}]
4491 [@option{-r}|@option{--relocs}]
4492 [@option{-u}|@option{--unwind}]
4493 [@option{-d}|@option{--dynamic}]
4494 [@option{-V}|@option{--version-info}]
4495 [@option{-A}|@option{--arch-specific}]
4496 [@option{-D}|@option{--use-dynamic}]
4497 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4498 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4499 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4500 [@option{-z}|@option{--decompress}]
4501 [@option{-c}|@option{--archive-index}]
4502 [@option{-w[lLiaprmfFsoRtUuTgAckK]}|
4503 @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]]
4504 [@option{--dwarf-depth=@var{n}}]
4505 [@option{--dwarf-start=@var{n}}]
4506 [@option{-I}|@option{--histogram}]
4507 [@option{-v}|@option{--version}]
4508 [@option{-W}|@option{--wide}]
4509 [@option{-H}|@option{--help}]
4510 @var{elffile}@dots{}
4514 @c man begin DESCRIPTION readelf
4516 @command{readelf} displays information about one or more ELF format object
4517 files. The options control what particular information to display.
4519 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4520 64-bit ELF files are supported, as are archives containing ELF files.
4522 This program performs a similar function to @command{objdump} but it
4523 goes into more detail and it exists independently of the @sc{bfd}
4524 library, so if there is a bug in @sc{bfd} then readelf will not be
4529 @c man begin OPTIONS readelf
4531 The long and short forms of options, shown here as alternatives, are
4532 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4538 Equivalent to specifying @option{--file-header},
4539 @option{--program-headers}, @option{--sections}, @option{--symbols},
4540 @option{--relocs}, @option{--dynamic}, @option{--notes},
4541 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4542 @option{--section-groups} and @option{--histogram}.
4544 Note - this option does not enable @option{--use-dynamic} itself, so
4545 if that option is not present on the command line then dynamic symbols
4546 and dynamic relocs will not be displayed.
4549 @itemx --file-header
4550 @cindex ELF file header information
4551 Displays the information contained in the ELF header at the start of the
4555 @itemx --program-headers
4557 @cindex ELF program header information
4558 @cindex ELF segment information
4559 Displays the information contained in the file's segment headers, if it
4564 @itemx --section-headers
4565 @cindex ELF section information
4566 Displays the information contained in the file's section headers, if it
4570 @itemx --section-groups
4571 @cindex ELF section group information
4572 Displays the information contained in the file's section groups, if it
4576 @itemx --section-details
4577 @cindex ELF section information
4578 Displays the detailed section information. Implies @option{-S}.
4583 @cindex ELF symbol table information
4584 Displays the entries in symbol table section of the file, if it has one.
4585 If a symbol has version information associated with it then this is
4586 displayed as well. The version string is displayed as a suffix to the
4587 symbol name, preceeded by an @@ character. For example
4588 @samp{foo@@VER_1}. If the version is the default version to be used
4589 when resolving unversioned references to the symbol then it is
4590 displayed as a suffix preceeded by two @@ characters. For example
4591 @samp{foo@@@@VER_2}.
4594 @cindex ELF dynamic symbol table information
4595 Displays the entries in dynamic symbol table section of the file, if it
4596 has one. The output format is the same as the format used by the
4597 @option{--syms} option.
4601 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4606 Displays the contents of the NOTE segments and/or sections, if any.
4610 @cindex ELF reloc information
4611 Displays the contents of the file's relocation section, if it has one.
4615 @cindex unwind information
4616 Displays the contents of the file's unwind section, if it has one. Only
4617 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4618 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4622 @cindex ELF dynamic section information
4623 Displays the contents of the file's dynamic section, if it has one.
4626 @itemx --version-info
4627 @cindex ELF version sections information
4628 Displays the contents of the version sections in the file, it they
4632 @itemx --arch-specific
4633 Displays architecture-specific information in the file, if there
4637 @itemx --use-dynamic
4638 When displaying symbols, this option makes @command{readelf} use the
4639 symbol hash tables in the file's dynamic section, rather than the
4640 symbol table sections.
4642 When displaying relocations, this option makes @command{readelf}
4643 display the dynamic relocations rather than the static relocations.
4645 @item -x <number or name>
4646 @itemx --hex-dump=<number or name>
4647 Displays the contents of the indicated section as a hexadecimal bytes.
4648 A number identifies a particular section by index in the section table;
4649 any other string identifies all sections with that name in the object file.
4651 @item -R <number or name>
4652 @itemx --relocated-dump=<number or name>
4653 Displays the contents of the indicated section as a hexadecimal
4654 bytes. A number identifies a particular section by index in the
4655 section table; any other string identifies all sections with that name
4656 in the object file. The contents of the section will be relocated
4657 before they are displayed.
4659 @item -p <number or name>
4660 @itemx --string-dump=<number or name>
4661 Displays the contents of the indicated section as printable strings.
4662 A number identifies a particular section by index in the section table;
4663 any other string identifies all sections with that name in the object file.
4667 Requests that the section(s) being dumped by @option{x}, @option{R} or
4668 @option{p} options are decompressed before being displayed. If the
4669 section(s) are not compressed then they are displayed as is.
4672 @itemx --archive-index
4673 @cindex Archive file symbol index information
4674 Displays the file symbol index information contained in the header part
4675 of binary archives. Performs the same function as the @option{t}
4676 command to @command{ar}, but without using the BFD library. @xref{ar}.
4678 @item -w[lLiaprmfFsoRtUuTgAckK]
4679 @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]
4680 @include debug.options.texi
4684 Display a histogram of bucket list lengths when displaying the contents
4685 of the symbol tables.
4689 Display the version number of readelf.
4693 Don't break output lines to fit into 80 columns. By default
4694 @command{readelf} breaks section header and segment listing lines for
4695 64-bit ELF files, so that they fit into 80 columns. This option causes
4696 @command{readelf} to print each section header resp. each segment one a
4697 single line, which is far more readable on terminals wider than 80 columns.
4701 Display the command-line options understood by @command{readelf}.
4708 @c man begin SEEALSO readelf
4709 objdump(1), and the Info entries for @file{binutils}.
4716 @cindex Update ELF header
4719 @c man title elfedit Update the ELF header of ELF files.
4722 @c man begin SYNOPSIS elfedit
4723 elfedit [@option{--input-mach=}@var{machine}]
4724 [@option{--input-type=}@var{type}]
4725 [@option{--input-osabi=}@var{osabi}]
4726 @option{--output-mach=}@var{machine}
4727 @option{--output-type=}@var{type}
4728 @option{--output-osabi=}@var{osabi}
4729 [@option{-v}|@option{--version}]
4730 [@option{-h}|@option{--help}]
4731 @var{elffile}@dots{}
4735 @c man begin DESCRIPTION elfedit
4737 @command{elfedit} updates the ELF header of ELF files which have
4738 the matching ELF machine and file types. The options control how and
4739 which fields in the ELF header should be updated.
4741 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4742 64-bit ELF files are supported, as are archives containing ELF files.
4745 @c man begin OPTIONS elfedit
4747 The long and short forms of options, shown here as alternatives, are
4748 equivalent. At least one of the @option{--output-mach},
4749 @option{--output-type} and @option{--output-osabi} options must be given.
4753 @item --input-mach=@var{machine}
4754 Set the matching input ELF machine type to @var{machine}. If
4755 @option{--input-mach} isn't specified, it will match any ELF
4758 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4759 @var{K1OM} and @var{x86-64}.
4761 @item --output-mach=@var{machine}
4762 Change the ELF machine type in the ELF header to @var{machine}. The
4763 supported ELF machine types are the same as @option{--input-mach}.
4765 @item --input-type=@var{type}
4766 Set the matching input ELF file type to @var{type}. If
4767 @option{--input-type} isn't specified, it will match any ELF file types.
4769 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4771 @item --output-type=@var{type}
4772 Change the ELF file type in the ELF header to @var{type}. The
4773 supported ELF types are the same as @option{--input-type}.
4775 @item --input-osabi=@var{osabi}
4776 Set the matching input ELF file OSABI to @var{osabi}. If
4777 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4779 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4780 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4781 @var{Solaris}, @var{AIX}, @var{Irix},
4782 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4783 @var{NSK}, @var{AROS} and @var{FenixOS}.
4785 @item --output-osabi=@var{osabi}
4786 Change the ELF OSABI in the ELF header to @var{osabi}. The
4787 supported ELF OSABI are the same as @option{--input-osabi}.
4791 Display the version number of @command{elfedit}.
4795 Display the command-line options understood by @command{elfedit}.
4802 @c man begin SEEALSO elfedit
4803 readelf(1), and the Info entries for @file{binutils}.
4807 @node Common Options
4808 @chapter Common Options
4810 The following command-line options are supported by all of the
4811 programs described in this manual.
4813 @c man begin OPTIONS
4815 @include at-file.texi
4819 Display the command-line options supported by the program.
4822 Display the version number of the program.
4824 @c man begin OPTIONS
4828 @node Selecting the Target System
4829 @chapter Selecting the Target System
4831 You can specify two aspects of the target system to the @sc{gnu}
4832 binary file utilities, each in several ways:
4842 In the following summaries, the lists of ways to specify values are in
4843 order of decreasing precedence. The ways listed first override those
4846 The commands to list valid values only list the values for which the
4847 programs you are running were configured. If they were configured with
4848 @option{--enable-targets=all}, the commands list most of the available
4849 values, but a few are left out; not all targets can be configured in at
4850 once because some of them can only be configured @dfn{native} (on hosts
4851 with the same type as the target system).
4854 * Target Selection::
4855 * Architecture Selection::
4858 @node Target Selection
4859 @section Target Selection
4861 A @dfn{target} is an object file format. A given target may be
4862 supported for multiple architectures (@pxref{Architecture Selection}).
4863 A target selection may also have variations for different operating
4864 systems or architectures.
4866 The command to list valid target values is @samp{objdump -i}
4867 (the first column of output contains the relevant information).
4869 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4870 @samp{a.out-sunos-big}.
4872 You can also specify a target using a configuration triplet. This is
4873 the same sort of name that is passed to @file{configure} to specify a
4874 target. When you use a configuration triplet as an argument, it must be
4875 fully canonicalized. You can see the canonical version of a triplet by
4876 running the shell script @file{config.sub} which is included with the
4879 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4880 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4882 @subheading @command{objdump} Target
4888 command-line option: @option{-b} or @option{--target}
4891 environment variable @code{GNUTARGET}
4894 deduced from the input file
4897 @subheading @command{objcopy} and @command{strip} Input Target
4903 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
4906 environment variable @code{GNUTARGET}
4909 deduced from the input file
4912 @subheading @command{objcopy} and @command{strip} Output Target
4918 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
4921 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
4924 environment variable @code{GNUTARGET}
4927 deduced from the input file
4930 @subheading @command{nm}, @command{size}, and @command{strings} Target
4936 command-line option: @option{--target}
4939 environment variable @code{GNUTARGET}
4942 deduced from the input file
4945 @node Architecture Selection
4946 @section Architecture Selection
4948 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4949 to run. Its name may contain a colon, separating the name of the
4950 processor family from the name of the particular @sc{cpu}.
4952 The command to list valid architecture values is @samp{objdump -i} (the
4953 second column contains the relevant information).
4955 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4957 @subheading @command{objdump} Architecture
4963 command-line option: @option{-m} or @option{--architecture}
4966 deduced from the input file
4969 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4975 deduced from the input file
4978 @node Reporting Bugs
4979 @chapter Reporting Bugs
4981 @cindex reporting bugs
4983 Your bug reports play an essential role in making the binary utilities
4986 Reporting a bug may help you by bringing a solution to your problem, or
4987 it may not. But in any case the principal function of a bug report is
4988 to help the entire community by making the next version of the binary
4989 utilities work better. Bug reports are your contribution to their
4992 In order for a bug report to serve its purpose, you must include the
4993 information that enables us to fix the bug.
4996 * Bug Criteria:: Have you found a bug?
4997 * Bug Reporting:: How to report bugs
5001 @section Have You Found a Bug?
5002 @cindex bug criteria
5004 If you are not sure whether you have found a bug, here are some guidelines:
5007 @cindex fatal signal
5010 If a binary utility gets a fatal signal, for any input whatever, that is
5011 a bug. Reliable utilities never crash.
5013 @cindex error on valid input
5015 If a binary utility produces an error message for valid input, that is a
5019 If you are an experienced user of binary utilities, your suggestions for
5020 improvement are welcome in any case.
5024 @section How to Report Bugs
5026 @cindex bugs, reporting
5028 A number of companies and individuals offer support for @sc{gnu}
5029 products. If you obtained the binary utilities from a support
5030 organization, we recommend you contact that organization first.
5032 You can find contact information for many support companies and
5033 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5037 In any event, we also recommend that you send bug reports for the binary
5038 utilities to @value{BUGURL}.
5041 The fundamental principle of reporting bugs usefully is this:
5042 @strong{report all the facts}. If you are not sure whether to state a
5043 fact or leave it out, state it!
5045 Often people omit facts because they think they know what causes the
5046 problem and assume that some details do not matter. Thus, you might
5047 assume that the name of a file you use in an example does not matter.
5048 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5049 a stray memory reference which happens to fetch from the location where
5050 that pathname is stored in memory; perhaps, if the pathname were
5051 different, the contents of that location would fool the utility into
5052 doing the right thing despite the bug. Play it safe and give a
5053 specific, complete example. That is the easiest thing for you to do,
5054 and the most helpful.
5056 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5057 it is new to us. Therefore, always write your bug reports on the assumption
5058 that the bug has not been reported previously.
5060 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5061 bell?'' This cannot help us fix a bug, so it is basically useless. We
5062 respond by asking for enough details to enable us to investigate.
5063 You might as well expedite matters by sending them to begin with.
5065 To enable us to fix the bug, you should include all these things:
5069 The version of the utility. Each utility announces it if you start it
5070 with the @option{--version} argument.
5072 Without this, we will not know whether there is any point in looking for
5073 the bug in the current version of the binary utilities.
5076 Any patches you may have applied to the source, including any patches
5077 made to the @code{BFD} library.
5080 The type of machine you are using, and the operating system name and
5084 What compiler (and its version) was used to compile the utilities---e.g.
5088 The command arguments you gave the utility to observe the bug. To
5089 guarantee you will not omit something important, list them all. A copy
5090 of the Makefile (or the output from make) is sufficient.
5092 If we were to try to guess the arguments, we would probably guess wrong
5093 and then we might not encounter the bug.
5096 A complete input file, or set of input files, that will reproduce the
5097 bug. If the utility is reading an object file or files, then it is
5098 generally most helpful to send the actual object files.
5100 If the source files were produced exclusively using @sc{gnu} programs
5101 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5102 may be OK to send the source files rather than the object files. In
5103 this case, be sure to say exactly what version of @command{gcc}, or
5104 whatever, was used to produce the object files. Also say how
5105 @command{gcc}, or whatever, was configured.
5108 A description of what behavior you observe that you believe is
5109 incorrect. For example, ``It gets a fatal signal.''
5111 Of course, if the bug is that the utility gets a fatal signal, then we
5112 will certainly notice it. But if the bug is incorrect output, we might
5113 not notice unless it is glaringly wrong. You might as well not give us
5114 a chance to make a mistake.
5116 Even if the problem you experience is a fatal signal, you should still
5117 say so explicitly. Suppose something strange is going on, such as your
5118 copy of the utility is out of sync, or you have encountered a bug in
5119 the C library on your system. (This has happened!) Your copy might
5120 crash and ours would not. If you told us to expect a crash, then when
5121 ours fails to crash, we would know that the bug was not happening for
5122 us. If you had not told us to expect a crash, then we would not be able
5123 to draw any conclusion from our observations.
5126 If you wish to suggest changes to the source, send us context diffs, as
5127 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5128 option. Always send diffs from the old file to the new file. If you
5129 wish to discuss something in the @command{ld} source, refer to it by
5130 context, not by line number.
5132 The line numbers in our development sources will not match those in your
5133 sources. Your line numbers would convey no useful information to us.
5136 Here are some things that are not necessary:
5140 A description of the envelope of the bug.
5142 Often people who encounter a bug spend a lot of time investigating
5143 which changes to the input file will make the bug go away and which
5144 changes will not affect it.
5146 This is often time consuming and not very useful, because the way we
5147 will find the bug is by running a single example under the debugger
5148 with breakpoints, not by pure deduction from a series of examples.
5149 We recommend that you save your time for something else.
5151 Of course, if you can find a simpler example to report @emph{instead}
5152 of the original one, that is a convenience for us. Errors in the
5153 output will be easier to spot, running under the debugger will take
5154 less time, and so on.
5156 However, simplification is not vital; if you do not want to do this,
5157 report the bug anyway and send us the entire test case you used.
5160 A patch for the bug.
5162 A patch for the bug does help us if it is a good one. But do not omit
5163 the necessary information, such as the test case, on the assumption that
5164 a patch is all we need. We might see problems with your patch and decide
5165 to fix the problem another way, or we might not understand it at all.
5167 Sometimes with programs as complicated as the binary utilities it is
5168 very hard to construct an example that will make the program follow a
5169 certain path through the code. If you do not send us the example, we
5170 will not be able to construct one, so we will not be able to verify that
5173 And if we cannot understand what bug you are trying to fix, or why your
5174 patch should be an improvement, we will not install it. A test case will
5175 help us to understand.
5178 A guess about what the bug is or what it depends on.
5180 Such guesses are usually wrong. Even we cannot guess right about such
5181 things without first using the debugger to find the facts.
5184 @node GNU Free Documentation License
5185 @appendix GNU Free Documentation License
5189 @node Binutils Index
5190 @unnumbered Binutils Index