1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2023 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 ELF header and property 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 and program property of ELF files.
117 Demangle encoded C++ symbols (on MS-DOS, this program is named
121 Convert addresses or symbol+offset 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 or symbol+offset to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update ELF header and property of ELF files
155 * Common Options:: Command-line options for all utilities
156 * Selecting the Target System:: How these utilities determine the target
157 * debuginfod:: Using binutils with debuginfod
158 * Reporting Bugs:: Reporting Bugs
159 * GNU Free Documentation License:: GNU Free Documentation License
160 * Binutils Index:: Binutils Index
168 @cindex collections of files
170 @c man title ar create, modify, and extract from archives
173 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
174 ar -M [ <mri-script ]
177 @c man begin DESCRIPTION ar
179 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
180 archives. An @dfn{archive} is a single file holding a collection of
181 other files in a structure that makes it possible to retrieve
182 the original individual files (called @dfn{members} of the archive).
184 The original files' contents, mode (permissions), timestamp, owner, and
185 group are preserved in the archive, and can be restored on
189 @sc{gnu} @command{ar} can maintain archives whose members have names of any
190 length; however, depending on how @command{ar} is configured on your
191 system, a limit on member-name length may be imposed for compatibility
192 with archive formats maintained with other tools. If it exists, the
193 limit is often 15 characters (typical of formats related to a.out) or 16
194 characters (typical of formats related to coff).
197 @command{ar} is considered a binary utility because archives of this sort
198 are most often used as @dfn{libraries} holding commonly needed
199 subroutines. Since libraries often will depend on other libraries,
200 @command{ar} can also record the dependencies of a library when the
201 @option{--record-libdeps} option is specified.
204 @command{ar} creates an index to the symbols defined in relocatable
205 object modules in the archive when you specify the modifier @samp{s}.
206 Once created, this index is updated in the archive whenever @command{ar}
207 makes a change to its contents (save for the @samp{q} update operation).
208 An archive with such an index speeds up linking to the library, and
209 allows routines in the library to call each other without regard to
210 their placement in the archive.
212 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
213 table. If an archive lacks the table, another form of @command{ar} called
214 @command{ranlib} can be used to add just the table.
216 @cindex thin archives
217 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
218 which contains a symbol index and references to the original copies
219 of the member files of the archive. This is useful for building
220 libraries for use within a local build tree, where the relocatable
221 objects are expected to remain available, and copying the contents of
222 each object would only waste time and space.
224 An archive can either be @emph{thin} or it can be normal. It cannot
225 be both at the same time. Once an archive is created its format
226 cannot be changed without first deleting it and then creating a new
227 archive in its place.
229 Thin archives are also @emph{flattened}, so that adding one thin
230 archive to another thin archive does not nest it, as would happen with
231 a normal archive. Instead the elements of the first archive are added
232 individually to the second archive.
234 The paths to the elements of the archive are stored relative to the
237 @cindex compatibility, @command{ar}
238 @cindex @command{ar} compatibility
239 @sc{gnu} @command{ar} is designed to be compatible with two different
240 facilities. You can control its activity using command-line options,
241 like the different varieties of @command{ar} on Unix systems; or, if you
242 specify the single command-line option @option{-M}, you can control it
243 with a script supplied via standard input, like the MRI ``librarian''
249 * ar cmdline:: Controlling @command{ar} on the command line
250 * ar scripts:: Controlling @command{ar} with a script
255 @section Controlling @command{ar} on the Command Line
258 @c man begin SYNOPSIS ar
259 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@option{--output} @var{dirname}] [@option{--record-libdeps} @var{libdeps}] [@option{--thin}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
263 @cindex Unix compatibility, @command{ar}
264 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
265 arguments to execute: one keyletter specifying the @emph{operation}
266 (optionally accompanied by other keyletters specifying
267 @emph{modifiers}), and the archive name to act on.
269 Most operations can also accept further @var{member} arguments,
270 specifying particular files to operate on.
272 @c man begin OPTIONS ar
274 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
275 flags @var{mod} in any order, within the first command-line argument.
277 If you wish, you may begin the first command-line argument with a
280 @cindex operations on archive
281 The @var{p} keyletter specifies what operation to execute; it may be
282 any of the following, but you must specify only one of them:
286 @cindex deleting from archive
287 @emph{Delete} modules from the archive. Specify the names of modules to
288 be deleted as @var{member}@dots{}; the archive is untouched if you
289 specify no files to delete.
291 If you specify the @samp{v} modifier, @command{ar} lists each module
295 @cindex moving in archive
296 Use this operation to @emph{move} members in an archive.
298 The ordering of members in an archive can make a difference in how
299 programs are linked using the library, if a symbol is defined in more
302 If no modifiers are used with @code{m}, any members you name in the
303 @var{member} arguments are moved to the @emph{end} of the archive;
304 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
305 specified place instead.
308 @cindex printing from archive
309 @emph{Print} the specified members of the archive, to the standard
310 output file. If the @samp{v} modifier is specified, show the member
311 name before copying its contents to standard output.
313 If you specify no @var{member} arguments, all the files in the archive are
317 @cindex quick append to archive
318 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
319 @var{archive}, without checking for replacement.
321 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
322 operation; new members are always placed at the end of the archive.
324 The modifier @samp{v} makes @command{ar} list each file as it is appended.
326 Since the point of this operation is speed, implementations of
327 @command{ar} have the option of not updating the archive's symbol
328 table if one exists. Too many different systems however assume that
329 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
330 rebuild the table even with a quick append.
332 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
333 synonym for @samp{r} - replacing already existing files in the
334 archive and appending new ones at the end.
337 @cindex replacement in archive
338 Insert the files @var{member}@dots{} into @var{archive} (with
339 @emph{replacement}). This operation differs from @samp{q} in that any
340 previously existing members are deleted if their names match those being
343 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
344 displays an error message, and leaves undisturbed any existing members
345 of the archive matching that name.
347 By default, new members are added at the end of the file; but you may
348 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
349 placement relative to some existing member.
351 The modifier @samp{v} used with this operation elicits a line of
352 output for each file inserted, along with one of the letters @samp{a} or
353 @samp{r} to indicate whether the file was appended (no old member
354 deleted) or replaced.
358 Add an index to the archive, or update it if it already exists. Note
359 this command is an exception to the rule that there can only be one
360 command letter, as it is possible to use it as either a command or a
361 modifier. In either case it does the same thing.
364 @cindex contents of archive
365 Display a @emph{table} listing the contents of @var{archive}, or those
366 of the files listed in @var{member}@dots{} that are present in the
367 archive. Normally only the member name is shown, but if the modifier
368 @samp{O} is specified, then the corresponding offset of the member is also
369 displayed. Finally, in order to see the modes (permissions), timestamp,
370 owner, group, and size the @samp{v} modifier should be included.
372 If you do not specify a @var{member}, all files in the archive
375 @cindex repeated names in archive
376 @cindex name duplication in archive
377 If there is more than one file with the same name (say, @samp{fie}) in
378 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
379 first instance; to see them all, you must ask for a complete
380 listing---in our example, @samp{ar t b.a}.
381 @c WRS only; per Gumby, this is implementation-dependent, and in a more
382 @c recent case in fact works the other way.
385 @cindex extract from archive
386 @emph{Extract} members (named @var{member}) from the archive. You can
387 use the @samp{v} modifier with this operation, to request that
388 @command{ar} list each name as it extracts it.
390 If you do not specify a @var{member}, all files in the archive
393 Files cannot be extracted from a thin archive, and there are
394 restrictions on extracting from archives created with @option{P}: The
395 paths must not be absolute, may not contain @code{..}, and any
396 subdirectories in the paths must exist. If it is desired to avoid
397 these restrictions then used the @option{--output} option to specify
401 A number of modifiers (@var{mod}) may immediately follow the @var{p}
402 keyletter, to specify variations on an operation's behavior:
406 @cindex relative placement in archive
407 Add new files @emph{after} an existing member of the
408 archive. If you use the modifier @samp{a}, the name of an existing archive
409 member must be present as the @var{relpos} argument, before the
410 @var{archive} specification.
413 Add new files @emph{before} an existing member of the
414 archive. If you use the modifier @samp{b}, the name of an existing archive
415 member must be present as the @var{relpos} argument, before the
416 @var{archive} specification. (same as @samp{i}).
419 @cindex creating archives
420 @emph{Create} the archive. The specified @var{archive} is always
421 created if it did not exist, when you request an update. But a warning is
422 issued unless you specify in advance that you expect to create it, by
426 @cindex deterministic archives
427 @kindex --enable-deterministic-archives
428 Operate in @emph{deterministic} mode. When adding files and the archive
429 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
430 for all files. When this option is used, if @command{ar} is used with
431 identical options and identical input files, multiple runs will create
432 identical output files regardless of the input files' owners, groups,
433 file modes, or modification times.
435 If @file{binutils} was configured with
436 @option{--enable-deterministic-archives}, then this mode is on by default.
437 It can be disabled with the @samp{U} modifier, below.
440 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
441 names of any length. This will cause it to create archives which are
442 not compatible with the native @command{ar} program on some systems. If
443 this is a concern, the @samp{f} modifier may be used to truncate file
444 names when putting them in the archive.
447 Insert new files @emph{before} an existing member of the
448 archive. If you use the modifier @samp{i}, the name of an existing archive
449 member must be present as the @var{relpos} argument, before the
450 @var{archive} specification. (same as @samp{b}).
453 @c This modifier was accepted but not used.
454 @c whaffor ar l modifier??? presumably compat; with
455 @c what???---doc@@cygnus.com, 25jan91
456 Specify dependencies of this library. The dependencies must immediately
457 follow this option character, must use the same syntax as the linker
458 command line, and must be specified within a single argument. I.e., if
459 multiple items are needed, they must be quoted to form a single command
460 line argument. For example @samp{L "-L/usr/local/lib -lmydep1 -lmydep2"}
463 Uses the @var{count} parameter. This is used if there are multiple
464 entries in the archive with the same name. Extract or delete instance
465 @var{count} of the given name from the archive.
468 @cindex dates in archive
469 Preserve the @emph{original} dates of members when extracting them. If
470 you do not specify this modifier, files extracted from the archive
471 are stamped with the time of extraction.
474 @cindex offsets of files
475 Display member offsets inside the archive. Use together with the @samp{t}
479 Use the full path name when matching or storing names in the archive.
480 Archives created with full path names are not POSIX compliant, and
481 thus may not work with tools other than up to date @sc{gnu} tools.
482 Modifying such archives with @sc{gnu} @command{ar} without using
483 @option{P} will remove the full path names unless the archive is a
484 thin archive. Note that @option{P} may be useful when adding files to
485 a thin archive since @option{r} without @option{P} ignores the path
486 when choosing which element to replace. Thus
488 ar rcST archive.a subdir/file1 subdir/file2 file1
490 will result in the first @code{subdir/file1} being replaced with
491 @code{file1} from the current directory. Adding @option{P} will
492 prevent this replacement.
495 @cindex writing archive index
496 Write an object-file index into the archive, or update an existing one,
497 even if no other change is made to the archive. You may use this modifier
498 flag either with any operation, or alone. Running @samp{ar s} on an
499 archive is equivalent to running @samp{ranlib} on it.
502 @cindex not writing archive index
503 Do not generate an archive symbol table. This can speed up building a
504 large library in several steps. The resulting archive can not be used
505 with the linker. In order to build a symbol table, you must omit the
506 @samp{S} modifier on the last execution of @samp{ar}, or you must run
507 @samp{ranlib} on the archive.
510 Deprecated alias for @option{--thin}. @option{T} is not recommended because in
511 many ar implementations @option{T} has a different meaning, as specified by
512 X/Open System Interface.
515 @cindex updating an archive
516 Normally, @samp{ar r}@dots{} inserts all files
517 listed into the archive. If you would like to insert @emph{only} those
518 of the files you list that are newer than existing members of the same
519 names, use this modifier. The @samp{u} modifier is allowed only for the
520 operation @samp{r} (replace). In particular, the combination @samp{qu} is
521 not allowed, since checking the timestamps would lose any speed
522 advantage from the operation @samp{q}.
524 Note - if an archive has been created in a deterministic manner, eg
525 via the use of the @option{D} modifier, then replacement will always
526 happen and the @option{u} modifier will be ineffective.
529 @cindex deterministic archives
530 @kindex --enable-deterministic-archives
531 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
532 of the @samp{D} modifier, above: added files and the archive index will
533 get their actual UID, GID, timestamp, and file mode values.
535 This is the default unless @file{binutils} was configured with
536 @option{--enable-deterministic-archives}.
539 This modifier requests the @emph{verbose} version of an operation. Many
540 operations display additional information, such as filenames processed,
541 when the modifier @samp{v} is appended.
544 This modifier shows the version number of @command{ar}.
547 The @command{ar} program also supports some command-line options which
548 are neither modifiers nor actions, but which do change its behaviour
553 Displays the list of command-line options supported by @command{ar}
557 Displays the version information of @command{ar} and then exits.
560 @command{ar} ignores an initial option spelled @samp{-X32_64}, for
561 compatibility with AIX. The behaviour produced by this option is the
562 default for @sc{gnu} @command{ar}. @command{ar} does not support any
563 of the other @samp{-X} options; in particular, it does not support
564 @option{-X32} which is the default for AIX @command{ar}.
566 @item --plugin @var{name}
568 The optional command-line switch @option{--plugin @var{name}} causes
569 @command{ar} to load the plugin called @var{name} which adds support
570 for more file formats, including object files with link-time
571 optimization information.
573 This option is only available if the toolchain has been built with
574 plugin support enabled.
576 If @option{--plugin} is not provided, but plugin support has been
577 enabled then @command{ar} iterates over the files in
578 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
579 plugin that claims the object in question is used.
581 Please note that this plugin search directory is @emph{not} the one
582 used by @command{ld}'s @option{-plugin} option. In order to make
583 @command{ar} use the linker plugin it must be copied into the
584 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
585 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
586 based compilations it is called @file{LLVMgold.so}. The GCC plugin
587 is always backwards compatible with earlier versions, so it is
588 sufficient to just copy the newest one.
590 @item --target @var{target}
591 The optional command-line switch @option{--target @var{bfdname}}
592 specifies that the archive members are in an object code format
593 different from your system's default format. See
594 @xref{Target Selection}, for more information.
596 @item --output @var{dirname}
597 The @option{--output} option can be used to specify a path to a
598 directory into which archive members should be extracted. If this
599 option is not specified then the current directory will be used.
601 Note - although the presence of this option does imply a @option{x}
602 extraction operation that option must still be included on the command
605 @item --record-libdeps @var{libdeps}
606 The @option{--record-libdeps} option is identical to the @option{l} modifier,
607 just handled in long form.
610 @cindex creating thin archive
611 Make the specified @var{archive} a @emph{thin} archive. If it already
612 exists and is a regular archive, the existing members must be present
613 in the same directory as @var{archive}.
619 @c man begin SEEALSO ar
620 nm(1), ranlib(1), and the Info entries for @file{binutils}.
625 @section Controlling @command{ar} with a Script
628 ar -M [ <@var{script} ]
631 @cindex MRI compatibility, @command{ar}
632 @cindex scripts, @command{ar}
633 If you use the single command-line option @samp{-M} with @command{ar}, you
634 can control its operation with a rudimentary command language. This
635 form of @command{ar} operates interactively if standard input is coming
636 directly from a terminal. During interactive use, @command{ar} prompts for
637 input (the prompt is @samp{AR >}), and continues executing even after
638 errors. If you redirect standard input to a script file, no prompts are
639 issued, and @command{ar} abandons execution (with a nonzero exit code)
642 The @command{ar} command language is @emph{not} designed to be equivalent
643 to the command-line options; in fact, it provides somewhat less control
644 over archives. The only purpose of the command language is to ease the
645 transition to @sc{gnu} @command{ar} for developers who already have scripts
646 written for the MRI ``librarian'' program.
648 The syntax for the @command{ar} command language is straightforward:
651 commands are recognized in upper or lower case; for example, @code{LIST}
652 is the same as @code{list}. In the following descriptions, commands are
653 shown in upper case for clarity.
656 a single command may appear on each line; it is the first word on the
660 empty lines are allowed, and have no effect.
663 comments are allowed; text after either of the characters @samp{*}
664 or @samp{;} is ignored.
667 Whenever you use a list of names as part of the argument to an @command{ar}
668 command, you can separate the individual names with either commas or
669 blanks. Commas are shown in the explanations below, for clarity.
672 @samp{+} is used as a line continuation character; if @samp{+} appears
673 at the end of a line, the text on the following line is considered part
674 of the current command.
677 Here are the commands you can use in @command{ar} scripts, or when using
678 @command{ar} interactively. Three of them have special significance:
680 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
681 a temporary file required for most of the other commands.
683 @code{SAVE} commits the changes so far specified by the script. Prior
684 to @code{SAVE}, commands affect only the temporary copy of the current
688 @item ADDLIB @var{archive}
689 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
690 Add all the contents of @var{archive} (or, if specified, each named
691 @var{module} from @var{archive}) to the current archive.
693 Requires prior use of @code{OPEN} or @code{CREATE}.
695 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
696 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
697 @c else like "ar q..."
698 Add each named @var{member} as a module in the current archive.
700 Requires prior use of @code{OPEN} or @code{CREATE}.
703 Discard the contents of the current archive, canceling the effect of
704 any operations since the last @code{SAVE}. May be executed (with no
705 effect) even if no current archive is specified.
707 @item CREATE @var{archive}
708 Creates an archive, and makes it the current archive (required for many
709 other commands). The new archive is created with a temporary name; it
710 is not actually saved as @var{archive} until you use @code{SAVE}.
711 You can overwrite existing archives; similarly, the contents of any
712 existing file named @var{archive} will not be destroyed until @code{SAVE}.
714 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
715 Delete each listed @var{module} from the current archive; equivalent to
716 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
718 Requires prior use of @code{OPEN} or @code{CREATE}.
720 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
721 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
722 List each named @var{module} present in @var{archive}. The separate
723 command @code{VERBOSE} specifies the form of the output: when verbose
724 output is off, output is like that of @samp{ar -t @var{archive}
725 @var{module}@dots{}}. When verbose output is on, the listing is like
726 @samp{ar -tv @var{archive} @var{module}@dots{}}.
728 Output normally goes to the standard output stream; however, if you
729 specify @var{outputfile} as a final argument, @command{ar} directs the
733 Exit from @command{ar}, with a @code{0} exit code to indicate successful
734 completion. This command does not save the output file; if you have
735 changed the current archive since the last @code{SAVE} command, those
738 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
739 Extract each named @var{module} from the current archive, writing them
740 into the current directory as separate files. Equivalent to @samp{ar -x
741 @var{archive} @var{module}@dots{}}.
743 Requires prior use of @code{OPEN} or @code{CREATE}.
746 @c FIXME Tokens but no commands???
753 Display full contents of the current archive, in ``verbose'' style
754 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
755 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
756 enhancement, rather than present for MRI compatibility.)
758 Requires prior use of @code{OPEN} or @code{CREATE}.
760 @item OPEN @var{archive}
761 Opens an existing archive for use as the current archive (required for
762 many other commands). Any changes as the result of subsequent commands
763 will not actually affect @var{archive} until you next use @code{SAVE}.
765 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
766 In the current archive, replace each existing @var{module} (named in
767 the @code{REPLACE} arguments) from files in the current working directory.
768 To execute this command without errors, both the file, and the module in
769 the current archive, must exist.
771 Requires prior use of @code{OPEN} or @code{CREATE}.
774 Toggle an internal flag governing the output from @code{DIRECTORY}.
775 When the flag is on, @code{DIRECTORY} output matches output from
776 @samp{ar -tv }@dots{}.
779 Commit your changes to the current archive, and actually save it as a
780 file with the name specified in the last @code{CREATE} or @code{OPEN}
783 Requires prior use of @code{OPEN} or @code{CREATE}.
792 The @sc{gnu} linker @command{ld} is now described in a separate manual.
793 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
801 @c man title nm list symbols from object files
804 @c man begin SYNOPSIS nm
805 nm [@option{-A}|@option{-o}|@option{--print-file-name}]
806 [@option{-a}|@option{--debug-syms}]
807 [@option{-B}|@option{--format=bsd}]
808 [@option{-C}|@option{--demangle}[=@var{style}]]
809 [@option{-D}|@option{--dynamic}]
810 [@option{-f}@var{format}|@option{--format=}@var{format}]
811 [@option{-g}|@option{--extern-only}]
812 [@option{-h}|@option{--help}]
813 [@option{--ifunc-chars=@var{CHARS}}]
814 [@option{-j}|@option{--format=just-symbols}]
815 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
816 [@option{-n}|@option{-v}|@option{--numeric-sort}]
817 [@option{-P}|@option{--portability}]
818 [@option{-p}|@option{--no-sort}]
819 [@option{-r}|@option{--reverse-sort}]
820 [@option{-S}|@option{--print-size}]
821 [@option{-s}|@option{--print-armap}]
822 [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
823 [@option{-u}|@option{--undefined-only}]
824 [@option{-U}|@option{--defined-only}]
825 [@option{-V}|@option{--version}]
826 [@option{-W}|@option{--no-weak}]
828 [@option{--no-demangle}]
829 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
830 [@option{--plugin} @var{name}]
831 [@option{--size-sort}]
832 [@option{--special-syms}]
833 [@option{--synthetic}]
834 [@option{--target=}@var{bfdname}]
835 [@option{--unicode=}@var{method}]
836 [@option{--with-symbol-versions}]
837 [@option{--without-symbol-versions}]
838 [@var{objfile}@dots{}]
842 @c man begin DESCRIPTION nm
843 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
844 If no object files are listed as arguments, @command{nm} assumes the file
847 For each symbol, @command{nm} shows:
851 The symbol value, in the radix selected by options (see below), or
852 hexadecimal by default.
855 The symbol type. At least the following types are used; others are, as
856 well, depending on the object file format. If lowercase, the symbol is
857 usually local; if uppercase, the symbol is global (external). There
858 are however a few lowercase symbols that are shown for special global
859 symbols (@code{u}, @code{v} and @code{w}).
861 @c Some more detail on exactly what these symbol types are used for
865 The symbol's value is absolute, and will not be changed by further
870 The symbol is in the BSS data section. This section typically
871 contains zero-initialized or uninitialized data, although the exact
872 behavior is system dependent.
876 The symbol is common. Common symbols are uninitialized data. When
877 linking, multiple common symbols may appear with the same name. If the
878 symbol is defined anywhere, the common symbols are treated as undefined
881 For more details on common symbols, see the discussion of
882 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
884 The lower case @var{c} character is used when the symbol is in a
885 special section for small commons.
889 The symbol is in the initialized data section.
893 The symbol is in an initialized data section for small objects. Some
894 object file formats permit more efficient access to small data objects,
895 such as a global int variable as opposed to a large global array.
898 For PE format files this indicates that the symbol is in a section
899 specific to the implementation of DLLs.
901 For ELF format files this indicates that the symbol is an indirect
902 function. This is a GNU extension to the standard set of ELF symbol
903 types. It indicates a symbol which if referenced by a relocation does
904 not evaluate to its address, but instead must be invoked at runtime.
905 The runtime execution will then return the value to be used in the
908 Note - the actual symbols display for GNU indirect symbols is
909 controlled by the @option{--ifunc-chars} command line option. If this
910 option has been provided then the first character in the string will
911 be used for global indirect function symbols. If the string contains
912 a second character then that will be used for local indirect function
916 The symbol is an indirect reference to another symbol.
919 The symbol is a debugging symbol.
922 The symbol is in a non-data, non-code, non-debug read-only section.
925 The symbol is in a stack unwind section.
929 The symbol is in a read only data section.
933 The symbol is in an uninitialized or zero-initialized data section
938 The symbol is in the text (code) section.
941 The symbol is undefined.
944 The symbol is a unique global symbol. This is a GNU extension to the
945 standard set of ELF symbol bindings. For such a symbol the dynamic linker
946 will make sure that in the entire process there is just one symbol with
947 this name and type in use.
951 The symbol is a weak object. When a weak defined symbol is linked with
952 a normal defined symbol, the normal defined symbol is used with no error.
953 When a weak undefined symbol is linked and the symbol is not defined,
954 the value of the weak symbol becomes zero with no error. On some
955 systems, uppercase indicates that a default value has been specified.
959 The symbol is a weak symbol that has not been specifically tagged as a
960 weak object symbol. When a weak defined symbol is linked with a normal
961 defined symbol, the normal defined symbol is used with no error.
962 When a weak undefined symbol is linked and the symbol is not defined,
963 the value of the symbol is determined in a system-specific manner without
964 error. On some systems, uppercase indicates that a default value has been
968 The symbol is a stabs symbol in an a.out object file. In this case, the
969 next values printed are the stabs other field, the stabs desc field, and
970 the stab type. Stabs symbols are used to hold debugging information.
973 The symbol type is unknown, or object file format specific.
977 The symbol name. If a symbol has version information associated with it,
978 then the version information is displayed as well. If the versioned
979 symbol is undefined or hidden from linker, the version string is displayed
980 as a suffix to the symbol name, preceded by an @@ character. For example
981 @samp{foo@@VER_1}. If the version is the default version to be used when
982 resolving unversioned references to the symbol, then it is displayed as a
983 suffix preceded by two @@ characters. For example @samp{foo@@@@VER_2}.
988 @c man begin OPTIONS nm
989 The long and short forms of options, shown here as alternatives, are
995 @itemx --print-file-name
996 @cindex input file name
998 @cindex source file name
999 Precede each symbol by the name of the input file (or archive member)
1000 in which it was found, rather than identifying the input file once only,
1001 before all of its symbols.
1005 @cindex debugging symbols
1006 Display all symbols, even debugger-only symbols; normally these are not
1010 @cindex @command{nm} format
1011 @cindex @command{nm} compatibility
1012 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
1015 @itemx --demangle[=@var{style}]
1016 @cindex demangling in nm
1017 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1018 Besides removing any initial underscore prepended by the system, this
1019 makes C++ function names readable. Different compilers have different
1020 mangling styles. The optional demangling style argument can be used to
1021 choose an appropriate demangling style for your compiler. @xref{c++filt},
1022 for more information on demangling.
1025 Do not demangle low-level symbol names. This is the default.
1027 @item --recurse-limit
1028 @itemx --no-recurse-limit
1029 @itemx --recursion-limit
1030 @itemx --no-recursion-limit
1031 Enables or disables a limit on the amount of recursion performed
1032 whilst demangling strings. Since the name mangling formats allow for
1033 an infinite level of recursion it is possible to create strings whose
1034 decoding will exhaust the amount of stack space available on the host
1035 machine, triggering a memory fault. The limit tries to prevent this
1036 from happening by restricting recursion to 2048 levels of nesting.
1038 The default is for this limit to be enabled, but disabling it may be
1039 necessary in order to demangle truly complicated names. Note however
1040 that if the recursion limit is disabled then stack exhaustion is
1041 possible and any bug reports about such an event will be rejected.
1045 @cindex dynamic symbols
1046 Display the dynamic symbols rather than the normal symbols. This is
1047 only meaningful for dynamic objects, such as certain types of shared
1050 @item -f @var{format}
1051 @itemx --format=@var{format}
1052 @cindex @command{nm} format
1053 @cindex @command{nm} compatibility
1054 Use the output format @var{format}, which can be @code{bsd},
1055 @code{sysv}, @code{posix} or @code{just-symbols}. The default is @code{bsd}.
1056 Only the first character of @var{format} is significant; it can be
1057 either upper or lower case.
1060 @itemx --extern-only
1061 @cindex external symbols
1062 Display only external symbols.
1066 Show a summary of the options to @command{nm} and exit.
1068 @item --ifunc-chars=@var{CHARS}
1069 When display GNU indirect function symbols @command{nm} will default
1070 to using the @code{i} character for both local indirect functions and
1071 global indirect functions. The @option{--ifunc-chars} option allows
1072 the user to specify a string containing one or two characters. The
1073 first character will be used for global indirect function symbols and
1074 the second character, if present, will be used for local indirect
1078 The same as @option{--format=just-symbols}.
1081 @itemx --line-numbers
1082 @cindex symbol line numbers
1083 For each symbol, use debugging information to try to find a filename and
1084 line number. For a defined symbol, look for the line number of the
1085 address of the symbol. For an undefined symbol, look for the line
1086 number of a relocation entry which refers to the symbol. If line number
1087 information can be found, print it after the other symbol information.
1090 @cindex objdump inlines
1091 When option @option{-l} is active, if the address belongs to a
1092 function that was inlined, then this option causes the source
1093 information for all enclosing scopes back to the first non-inlined
1094 function to be printed as well. For example, if @code{main} inlines
1095 @code{callee1} which inlines @code{callee2}, and address is from
1096 @code{callee2}, the source information for @code{callee1} and @code{main}
1097 will also be printed.
1101 @itemx --numeric-sort
1102 Sort symbols numerically by their addresses, rather than alphabetically
1107 @cindex sorting symbols
1108 Do not bother to sort the symbols in any order; print them in the order
1112 @itemx --portability
1113 Use the POSIX.2 standard output format instead of the default format.
1114 Equivalent to @samp{-f posix}.
1117 @itemx --reverse-sort
1118 Reverse the order of the sort (whether numeric or alphabetic); let the
1123 Print both value and size of defined symbols for the @code{bsd} output style.
1124 This option has no effect for object formats that do not record symbol
1125 sizes, unless @samp{--size-sort} is also used in which case a
1126 calculated size is displayed.
1129 @itemx --print-armap
1130 @cindex symbol index, listing
1131 When listing symbols from archive members, include the index: a mapping
1132 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1133 contain definitions for which names.
1135 @item -t @var{radix}
1136 @itemx --radix=@var{radix}
1137 Use @var{radix} as the radix for printing the symbol values. It must be
1138 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1141 @itemx --undefined-only
1142 @cindex external symbols
1143 @cindex undefined symbols
1144 Display only undefined symbols (those external to each object file).
1145 By default both defined and undefined symbols are displayed.
1148 @itemx --defined-only
1149 @cindex external symbols
1150 @cindex undefined symbols
1151 Display only defined symbols for each object file.
1152 By default both defined and undefined symbols are displayed.
1156 Show the version number of @command{nm} and exit.
1159 This option is ignored for compatibility with the AIX version of
1160 @command{nm}. It takes one parameter which must be the string
1161 @option{32_64}. The default mode of AIX @command{nm} corresponds
1162 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1164 @item --plugin @var{name}
1166 Load the plugin called @var{name} to add support for extra target
1167 types. This option is only available if the toolchain has been built
1168 with plugin support enabled.
1170 If @option{--plugin} is not provided, but plugin support has been
1171 enabled then @command{nm} iterates over the files in
1172 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1173 plugin that claims the object in question is used.
1175 Please note that this plugin search directory is @emph{not} the one
1176 used by @command{ld}'s @option{-plugin} option. In order to make
1177 @command{nm} use the linker plugin it must be copied into the
1178 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1179 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1180 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1181 is always backwards compatible with earlier versions, so it is
1182 sufficient to just copy the newest one.
1185 Sort symbols by size. For ELF objects symbol sizes are read from the
1186 ELF, for other object types the symbol sizes are computed as the
1187 difference between the value of the symbol and the value of the symbol
1188 with the next higher value. If the @code{bsd} output format is used
1189 the size of the symbol is printed, rather than the value, and
1190 @samp{-S} must be used in order both size and value to be printed.
1192 Note - this option does not work if @option{--undefined-only} has been
1193 enabled as undefined symbols have no size.
1195 @item --special-syms
1196 Display symbols which have a target-specific special meaning. These
1197 symbols are usually used by the target for some special processing and
1198 are not normally helpful when included in the normal symbol lists.
1199 For example for ARM targets this option would skip the mapping symbols
1200 used to mark transitions between ARM code, THUMB code and data.
1203 Include synthetic symbols in the output. These are special symbols
1204 created by the linker for various purposes. They are not shown by
1205 default since they are not part of the binary's original source code.
1207 @item --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
1208 Controls the display of UTF-8 encoded multibyte characters in strings.
1209 The default (@option{--unicode=default}) is to give them no special
1210 treatment. The @option{--unicode=locale} option displays the sequence
1211 in the current locale, which may or may not support them. The options
1212 @option{--unicode=hex} and @option{--unicode=invalid} display them as
1213 hex byte sequences enclosed by either angle brackets or curly braces.
1215 The @option{--unicode=escape} option displays them as escape sequences
1216 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
1217 them as escape sequences highlighted in red (if supported by the
1218 output device). The colouring is intended to draw attention to the
1219 presence of unicode sequences where they might not be expected.
1223 Do not display weak symbols.
1225 @item --with-symbol-versions
1226 @item --without-symbol-versions
1227 Enables or disables the display of symbol version information. The
1228 version string is displayed as a suffix to the symbol name, preceded
1229 by an @@ character. For example @samp{foo@@VER_1}. If the version is
1230 the default version to be used when resolving unversioned references
1231 to the symbol then it is displayed as a suffix preceded by two @@
1232 characters. For example @samp{foo@@@@VER_2}. By default, symbol
1233 version information is displayed.
1235 @item --target=@var{bfdname}
1236 @cindex object code format
1237 Specify an object code format other than your system's default format.
1238 @xref{Target Selection}, for more information.
1245 @c man begin SEEALSO nm
1246 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1253 @c man title objcopy copy and translate object files
1256 @c man begin SYNOPSIS objcopy
1257 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1258 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1259 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1260 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1261 [@option{-S}|@option{--strip-all}]
1262 [@option{-g}|@option{--strip-debug}]
1263 [@option{--strip-unneeded}]
1264 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1265 [@option{--keep-file-symbols}]
1266 [@option{--keep-section-symbols}]
1267 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1268 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1269 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1270 [@option{--localize-hidden}]
1271 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1272 [@option{--globalize-symbol=}@var{symbolname}]
1273 [@option{--globalize-symbols=}@var{filename}]
1274 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1275 [@option{-w}|@option{--wildcard}]
1276 [@option{-x}|@option{--discard-all}]
1277 [@option{-X}|@option{--discard-locals}]
1278 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1279 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1280 [@option{--interleave-width=}@var{width}]
1281 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1282 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1283 [@option{--keep-section=}@var{sectionpattern}]
1284 [@option{--remove-relocations=}@var{sectionpattern}]
1285 [@option{--strip-section-headers}]
1286 [@option{-p}|@option{--preserve-dates}]
1287 [@option{-D}|@option{--enable-deterministic-archives}]
1288 [@option{-U}|@option{--disable-deterministic-archives}]
1289 [@option{--debugging}]
1290 [@option{--gap-fill=}@var{val}]
1291 [@option{--pad-to=}@var{address}]
1292 [@option{--set-start=}@var{val}]
1293 [@option{--adjust-start=}@var{incr}]
1294 [@option{--change-addresses=}@var{incr}]
1295 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1296 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1297 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1298 [@option{--change-warnings}] [@option{--no-change-warnings}]
1299 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1300 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1301 [@option{--add-section} @var{sectionname}=@var{filename}]
1302 [@option{--dump-section} @var{sectionname}=@var{filename}]
1303 [@option{--update-section} @var{sectionname}=@var{filename}]
1304 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1305 [@option{--long-section-names} @{enable,disable,keep@}]
1306 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1307 [@option{--reverse-bytes=}@var{num}]
1308 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1309 [@option{--redefine-sym} @var{old}=@var{new}]
1310 [@option{--redefine-syms=}@var{filename}]
1312 [@option{--keep-symbols=}@var{filename}]
1313 [@option{--strip-symbols=}@var{filename}]
1314 [@option{--strip-unneeded-symbols=}@var{filename}]
1315 [@option{--keep-global-symbols=}@var{filename}]
1316 [@option{--localize-symbols=}@var{filename}]
1317 [@option{--weaken-symbols=}@var{filename}]
1318 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1319 [@option{--alt-machine-code=}@var{index}]
1320 [@option{--prefix-symbols=}@var{string}]
1321 [@option{--prefix-sections=}@var{string}]
1322 [@option{--prefix-alloc-sections=}@var{string}]
1323 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1324 [@option{--only-keep-debug}]
1325 [@option{--strip-dwo}]
1326 [@option{--extract-dwo}]
1327 [@option{--extract-symbol}]
1328 [@option{--writable-text}]
1329 [@option{--readonly-text}]
1332 [@option{--file-alignment=}@var{num}]
1333 [@option{--heap=}@var{reserve}[,@var{commit}]]
1334 [@option{--image-base=}@var{address}]
1335 [@option{--section-alignment=}@var{num}]
1336 [@option{--stack=}@var{reserve}[,@var{commit}]]
1337 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1338 [@option{--compress-debug-sections}]
1339 [@option{--decompress-debug-sections}]
1340 [@option{--elf-stt-common=@var{val}}]
1341 [@option{--merge-notes}]
1342 [@option{--no-merge-notes}]
1343 [@option{--verilog-data-width=@var{val}}]
1344 [@option{-v}|@option{--verbose}]
1345 [@option{-V}|@option{--version}]
1346 [@option{--help}] [@option{--info}]
1347 @var{infile} [@var{outfile}]
1351 @c man begin DESCRIPTION objcopy
1352 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1353 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1354 read and write the object files. It can write the destination object
1355 file in a format different from that of the source object file. The
1356 exact behavior of @command{objcopy} is controlled by command-line options.
1357 Note that @command{objcopy} should be able to copy a fully linked file
1358 between any two formats. However, copying a relocatable object file
1359 between any two formats may not work as expected.
1361 @command{objcopy} creates temporary files to do its translations and
1362 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1363 translation work; it has access to all the formats described in @sc{bfd}
1364 and thus is able to recognize most formats without being told
1365 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1367 @command{objcopy} can be used to generate S-records by using an output
1368 target of @samp{srec} (e.g., use @samp{-O srec}).
1370 @command{objcopy} can be used to generate a raw binary file by using an
1371 output target of @samp{binary} (e.g., use @option{-O binary}). When
1372 @command{objcopy} generates a raw binary file, it will essentially produce
1373 a memory dump of the contents of the input object file. All symbols and
1374 relocation information will be discarded. The memory dump will start at
1375 the load address of the lowest section copied into the output file.
1377 When generating an S-record or a raw binary file, it may be helpful to
1378 use @option{-S} to remove sections containing debugging information. In
1379 some cases @option{-R} will be useful to remove sections which contain
1380 information that is not needed by the binary file.
1382 Note---@command{objcopy} is not able to change the endianness of its input
1383 files. If the input format has an endianness (some formats do not),
1384 @command{objcopy} can only copy the inputs into file formats that have the
1385 same endianness or which have no endianness (e.g., @samp{srec}).
1386 (However, see the @option{--reverse-bytes} option.)
1390 @c man begin OPTIONS objcopy
1394 @itemx @var{outfile}
1395 The input and output files, respectively.
1396 If you do not specify @var{outfile}, @command{objcopy} creates a
1397 temporary file and destructively renames the result with
1398 the name of @var{infile}.
1400 @item -I @var{bfdname}
1401 @itemx --input-target=@var{bfdname}
1402 Consider the source file's object format to be @var{bfdname}, rather than
1403 attempting to deduce it. @xref{Target Selection}, for more information.
1405 @item -O @var{bfdname}
1406 @itemx --output-target=@var{bfdname}
1407 Write the output file using the object format @var{bfdname}.
1408 @xref{Target Selection}, for more information.
1410 @item -F @var{bfdname}
1411 @itemx --target=@var{bfdname}
1412 Use @var{bfdname} as the object format for both the input and the output
1413 file; i.e., simply transfer data from source to destination with no
1414 translation. @xref{Target Selection}, for more information.
1416 @item -B @var{bfdarch}
1417 @itemx --binary-architecture=@var{bfdarch}
1418 Useful when transforming a architecture-less input file into an object file.
1419 In this case the output architecture can be set to @var{bfdarch}. This
1420 option will be ignored if the input file has a known @var{bfdarch}. You
1421 can access this binary data inside a program by referencing the special
1422 symbols that are created by the conversion process. These symbols are
1423 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1424 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1425 an object file and then access it in your code using these symbols.
1427 @item -j @var{sectionpattern}
1428 @itemx --only-section=@var{sectionpattern}
1429 Copy only the indicated sections from the input file to the output file.
1430 This option may be given more than once. Note that using this option
1431 inappropriately may make the output file unusable. Wildcard
1432 characters are accepted in @var{sectionpattern}.
1434 If the first character of @var{sectionpattern} is the exclamation
1435 point (!) then matching sections will not be copied, even if earlier
1436 use of @option{--only-section} on the same command line would
1437 otherwise copy it. For example:
1440 --only-section=.text.* --only-section=!.text.foo
1443 will copy all sectinos matching '.text.*' but not the section
1446 @item -R @var{sectionpattern}
1447 @itemx --remove-section=@var{sectionpattern}
1448 Remove any section matching @var{sectionpattern} from the output file.
1449 This option may be given more than once. Note that using this option
1450 inappropriately may make the output file unusable. Wildcard
1451 characters are accepted in @var{sectionpattern}. Using both the
1452 @option{-j} and @option{-R} options together results in undefined
1455 If the first character of @var{sectionpattern} is the exclamation
1456 point (!) then matching sections will not be removed even if an
1457 earlier use of @option{--remove-section} on the same command line
1458 would otherwise remove it. For example:
1461 --remove-section=.text.* --remove-section=!.text.foo
1464 will remove all sections matching the pattern '.text.*', but will not
1465 remove the section '.text.foo'.
1467 @item --keep-section=@var{sectionpattern}
1468 When removing sections from the output file, keep sections that match
1469 @var{sectionpattern}.
1471 @item --remove-relocations=@var{sectionpattern}
1472 Remove non-dynamic relocations from the output file for any section
1473 matching @var{sectionpattern}. This option may be given more than
1474 once. Note that using this option inappropriately may make the output
1475 file unusable, and attempting to remove a dynamic relocation section
1476 such as @samp{.rela.plt} from an executable or shared library with
1477 @option{--remove-relocations=.plt} will not work. Wildcard characters
1478 are accepted in @var{sectionpattern}.
1482 --remove-relocations=.text.*
1485 will remove the relocations for all sections matching the pattern
1488 If the first character of @var{sectionpattern} is the exclamation
1489 point (!) then matching sections will not have their relocation
1490 removed even if an earlier use of @option{--remove-relocations} on the
1491 same command line would otherwise cause the relocations to be removed.
1495 --remove-relocations=.text.* --remove-relocations=!.text.foo
1498 will remove all relocations for sections matching the pattern
1499 '.text.*', but will not remove relocations for the section
1502 @item --strip-section-headers
1503 Strip section header This option is specific to ELF files.
1504 Implies @option{--strip-all} and @option{--merge-notes}.
1508 Do not copy relocation and symbol information from the source file.
1509 Also deletes debug sections.
1512 @itemx --strip-debug
1513 Do not copy debugging symbols or sections from the source file.
1515 @item --strip-unneeded
1516 Remove all symbols that are not needed for relocation processing in
1517 addition to debugging symbols and sections stripped by
1518 @option{--strip-debug}.
1520 @item -K @var{symbolname}
1521 @itemx --keep-symbol=@var{symbolname}
1522 When stripping symbols, keep symbol @var{symbolname} even if it would
1523 normally be stripped. This option may be given more than once.
1525 @item -N @var{symbolname}
1526 @itemx --strip-symbol=@var{symbolname}
1527 Do not copy symbol @var{symbolname} from the source file. This option
1528 may be given more than once.
1530 @item --strip-unneeded-symbol=@var{symbolname}
1531 Do not copy symbol @var{symbolname} from the source file unless it is needed
1532 by a relocation. This option may be given more than once.
1534 @item -G @var{symbolname}
1535 @itemx --keep-global-symbol=@var{symbolname}
1536 Keep only symbol @var{symbolname} global. Make all other symbols local
1537 to the file, so that they are not visible externally. This option may
1538 be given more than once. Note: this option cannot be used in
1539 conjunction with the @option{--globalize-symbol} or
1540 @option{--globalize-symbols} options.
1542 @item --localize-hidden
1543 In an ELF object, mark all symbols that have hidden or internal visibility
1544 as local. This option applies on top of symbol-specific localization options
1545 such as @option{-L}.
1547 @item -L @var{symbolname}
1548 @itemx --localize-symbol=@var{symbolname}
1549 Convert a global or weak symbol called @var{symbolname} into a local
1550 symbol, so that it is not visible externally. This option may be
1551 given more than once. Note - unique symbols are not converted.
1553 @item -W @var{symbolname}
1554 @itemx --weaken-symbol=@var{symbolname}
1555 Make symbol @var{symbolname} weak. This option may be given more than once.
1557 @item --globalize-symbol=@var{symbolname}
1558 Give symbol @var{symbolname} global scoping so that it is visible
1559 outside of the file in which it is defined. This option may be given
1560 more than once. Note: this option cannot be used in conjunction with
1561 the @option{-G} or @option{--keep-global-symbol} options.
1565 Permit regular expressions in @var{symbolname}s used in other command
1566 line options. The question mark (?), asterisk (*), backslash (\) and
1567 square brackets ([]) operators can be used anywhere in the symbol
1568 name. If the first character of the symbol name is the exclamation
1569 point (!) then the sense of the switch is reversed for that symbol.
1576 would cause objcopy to weaken all symbols that start with ``fo''
1577 except for the symbol ``foo''.
1580 @itemx --discard-all
1581 Do not copy non-global symbols from the source file.
1582 @c FIXME any reason to prefer "non-global" to "local" here?
1585 @itemx --discard-locals
1586 Do not copy compiler-generated local symbols.
1587 (These usually start with @samp{L} or @samp{.}.)
1590 @itemx --byte=@var{byte}
1591 If interleaving has been enabled via the @option{--interleave} option
1592 then start the range of bytes to keep at the @var{byte}th byte.
1593 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1594 @var{breadth} is the value given by the @option{--interleave} option.
1596 @item -i [@var{breadth}]
1597 @itemx --interleave[=@var{breadth}]
1598 Only copy a range out of every @var{breadth} bytes. (Header data is
1599 not affected). Select which byte in the range begins the copy with
1600 the @option{--byte} option. Select the width of the range with the
1601 @option{--interleave-width} option.
1603 This option is useful for creating files to program @sc{rom}. It is
1604 typically used with an @code{srec} output target. Note that
1605 @command{objcopy} will complain if you do not specify the
1606 @option{--byte} option as well.
1608 The default interleave breadth is 4, so with @option{--byte} set to 0,
1609 @command{objcopy} would copy the first byte out of every four bytes
1610 from the input to the output.
1612 @item --interleave-width=@var{width}
1613 When used with the @option{--interleave} option, copy @var{width}
1614 bytes at a time. The start of the range of bytes to be copied is set
1615 by the @option{--byte} option, and the extent of the range is set with
1616 the @option{--interleave} option.
1618 The default value for this option is 1. The value of @var{width} plus
1619 the @var{byte} value set by the @option{--byte} option must not exceed
1620 the interleave breadth set by the @option{--interleave} option.
1622 This option can be used to create images for two 16-bit flashes interleaved
1623 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1624 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1625 commands. If the input was '12345678' then the outputs would be
1626 '1256' and '3478' respectively.
1629 @itemx --preserve-dates
1630 Set the access and modification dates of the output file to be the same
1631 as those of the input file.
1633 This option also copies the date stored in a PE format file's header,
1634 unless the SOURCE_DATE_EPOCH environment variable is defined. If it
1635 is defined then this variable will be used as the date stored in the
1636 header, interpreted as the number of seconds since the Unix epoch.
1639 @itemx --enable-deterministic-archives
1640 @cindex deterministic archives
1641 @kindex --enable-deterministic-archives
1642 Operate in @emph{deterministic} mode. When copying archive members
1643 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1644 and use consistent file modes for all files.
1646 If @file{binutils} was configured with
1647 @option{--enable-deterministic-archives}, then this mode is on by default.
1648 It can be disabled with the @samp{-U} option, below.
1651 @itemx --disable-deterministic-archives
1652 @cindex deterministic archives
1653 @kindex --enable-deterministic-archives
1654 Do @emph{not} operate in @emph{deterministic} mode. This is the
1655 inverse of the @option{-D} option, above: when copying archive members
1656 and writing the archive index, use their actual UID, GID, timestamp,
1657 and file mode values.
1659 This is the default unless @file{binutils} was configured with
1660 @option{--enable-deterministic-archives}.
1663 Convert debugging information, if possible. This is not the default
1664 because only certain debugging formats are supported, and the
1665 conversion process can be time consuming.
1667 @item --gap-fill @var{val}
1668 Fill gaps between sections with @var{val}. This operation applies to
1669 the @emph{load address} (LMA) of the sections. It is done by increasing
1670 the size of the section with the lower address, and filling in the extra
1671 space created with @var{val}.
1673 @item --pad-to @var{address}
1674 Pad the output file up to the load address @var{address}. This is
1675 done by increasing the size of the last section. The extra space is
1676 filled in with the value specified by @option{--gap-fill} (default zero).
1678 @item --set-start @var{val}
1679 Set the start address (also known as the entry address) of the new
1680 file to @var{val}. Not all object file formats support setting the
1683 @item --change-start @var{incr}
1684 @itemx --adjust-start @var{incr}
1685 @cindex changing start address
1686 Change the start address (also known as the entry address) by adding
1687 @var{incr}. Not all object file formats support setting the start
1690 @item --change-addresses @var{incr}
1691 @itemx --adjust-vma @var{incr}
1692 @cindex changing object addresses
1693 Change the VMA and LMA addresses of all sections, as well as the start
1694 address, by adding @var{incr}. Some object file formats do not permit
1695 section addresses to be changed arbitrarily. Note that this does not
1696 relocate the sections; if the program expects sections to be loaded at a
1697 certain address, and this option is used to change the sections such
1698 that they are loaded at a different address, the program may fail.
1700 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1701 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1702 @cindex changing section address
1703 Set or change both the VMA address and the LMA address of any section
1704 matching @var{sectionpattern}. If @samp{=} is used, the section
1705 address is set to @var{val}. Otherwise, @var{val} is added to or
1706 subtracted from the section address. See the comments under
1707 @option{--change-addresses}, above. If @var{sectionpattern} does not
1708 match any sections in the input file, a warning will be issued, unless
1709 @option{--no-change-warnings} is used.
1711 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1712 @cindex changing section LMA
1713 Set or change the LMA address of any sections matching
1714 @var{sectionpattern}. The LMA address is the address where the
1715 section will be loaded into memory at program load time. Normally
1716 this is the same as the VMA address, which is the address of the
1717 section at program run time, but on some systems, especially those
1718 where a program is held in ROM, the two can be different. If @samp{=}
1719 is used, the section address is set to @var{val}. Otherwise,
1720 @var{val} is added to or subtracted from the section address. See the
1721 comments under @option{--change-addresses}, above. If
1722 @var{sectionpattern} does not match any sections in the input file, a
1723 warning will be issued, unless @option{--no-change-warnings} is used.
1725 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1726 @cindex changing section VMA
1727 Set or change the VMA address of any section matching
1728 @var{sectionpattern}. The VMA address is the address where the
1729 section will be located once the program has started executing.
1730 Normally this is the same as the LMA address, which is the address
1731 where the section will be loaded into memory, but on some systems,
1732 especially those where a program is held in ROM, the two can be
1733 different. If @samp{=} is used, the section address is set to
1734 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1735 section address. See the comments under @option{--change-addresses},
1736 above. If @var{sectionpattern} does not match any sections in the
1737 input file, a warning will be issued, unless
1738 @option{--no-change-warnings} is used.
1740 @item --change-warnings
1741 @itemx --adjust-warnings
1742 If @option{--change-section-address} or @option{--change-section-lma} or
1743 @option{--change-section-vma} is used, and the section pattern does not
1744 match any sections, issue a warning. This is the default.
1746 @item --no-change-warnings
1747 @itemx --no-adjust-warnings
1748 Do not issue a warning if @option{--change-section-address} or
1749 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1750 if the section pattern does not match any sections.
1752 @item --set-section-flags @var{sectionpattern}=@var{flags}
1753 Set the flags for any sections matching @var{sectionpattern}. The
1754 @var{flags} argument is a comma separated string of flag names. The
1755 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1756 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1757 @samp{exclude}, @samp{share}, @samp{debug}, and @samp{large}.
1758 You can set the @samp{contents} flag for a section which does not have
1759 contents, but it is not meaningful to clear the @samp{contents} flag of a
1760 section which does have contents--just remove the section instead. Not all
1761 flags are meaningful for all object file formats. In particular the
1762 @samp{share} flag is only meaningful for COFF format files and not for ELF
1763 format files. The ELF x86-64 specific flag @samp{large} corresponds to
1766 @item --set-section-alignment @var{sectionpattern}=@var{align}
1767 Set the alignment for any sections matching @var{sectionpattern}.
1768 @var{align} specifies the alignment in bytes and must be a power of
1769 two, i.e. 1, 2, 4, 8@dots{}.
1771 @item --add-section @var{sectionname}=@var{filename}
1772 Add a new section named @var{sectionname} while copying the file. The
1773 contents of the new section are taken from the file @var{filename}. The
1774 size of the section will be the size of the file. This option only
1775 works on file formats which can support sections with arbitrary names.
1776 Note - it may be necessary to use the @option{--set-section-flags}
1777 option to set the attributes of the newly created section.
1779 @item --dump-section @var{sectionname}=@var{filename}
1780 Place the contents of section named @var{sectionname} into the file
1781 @var{filename}, overwriting any contents that may have been there
1782 previously. This option is the inverse of @option{--add-section}.
1783 This option is similar to the @option{--only-section} option except
1784 that it does not create a formatted file, it just dumps the contents
1785 as raw binary data, without applying any relocations. The option can
1786 be specified more than once.
1788 @item --update-section @var{sectionname}=@var{filename}
1789 Replace the existing contents of a section named @var{sectionname}
1790 with the contents of file @var{filename}. The size of the section
1791 will be adjusted to the size of the file. The section flags for
1792 @var{sectionname} will be unchanged. For ELF format files the section
1793 to segment mapping will also remain unchanged, something which is not
1794 possible using @option{--remove-section} followed by
1795 @option{--add-section}. The option can be specified more than once.
1797 Note - it is possible to use @option{--rename-section} and
1798 @option{--update-section} to both update and rename a section from one
1799 command line. In this case, pass the original section name to
1800 @option{--update-section}, and the original and new section names to
1801 @option{--rename-section}.
1803 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1804 Add a new symbol named @var{name} while copying the file. This option may be
1805 specified multiple times. If the @var{section} is given, the symbol will be
1806 associated with and relative to that section, otherwise it will be an ABS
1807 symbol. Specifying an undefined section will result in a fatal error. There
1808 is no check for the value, it will be taken as specified. Symbol flags can
1809 be specified and not all flags will be meaningful for all object file
1810 formats. By default, the symbol will be global. The special flag
1811 'before=@var{othersym}' will insert the new symbol in front of the specified
1812 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1813 symbol table in the order they appear.
1815 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1816 Rename a section from @var{oldname} to @var{newname}, optionally
1817 changing the section's flags to @var{flags} in the process. This has
1818 the advantage over using a linker script to perform the rename in that
1819 the output stays as an object file and does not become a linked
1820 executable. This option accepts the same set of flags as the
1821 @option{--sect-section-flags} option.
1823 This option is particularly helpful when the input format is binary,
1824 since this will always create a section called .data. If for example,
1825 you wanted instead to create a section called .rodata containing binary
1826 data you could use the following command line to achieve it:
1829 objcopy -I binary -O <output_format> -B <architecture> \
1830 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1831 <input_binary_file> <output_object_file>
1834 @item --long-section-names @{enable,disable,keep@}
1835 Controls the handling of long section names when processing @code{COFF}
1836 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1837 is to preserve long section names if any are present in the input file.
1838 The @samp{enable} and @samp{disable} options forcibly enable or disable
1839 the use of long section names in the output object; when @samp{disable}
1840 is in effect, any long section names in the input object will be truncated.
1841 The @samp{enable} option will only emit long section names if any are
1842 present in the inputs; this is mostly the same as @samp{keep}, but it
1843 is left undefined whether the @samp{enable} option might force the
1844 creation of an empty string table in the output file.
1846 @item --change-leading-char
1847 Some object file formats use special characters at the start of
1848 symbols. The most common such character is underscore, which compilers
1849 often add before every symbol. This option tells @command{objcopy} to
1850 change the leading character of every symbol when it converts between
1851 object file formats. If the object file formats use the same leading
1852 character, this option has no effect. Otherwise, it will add a
1853 character, or remove a character, or change a character, as
1856 @item --remove-leading-char
1857 If the first character of a global symbol is a special symbol leading
1858 character used by the object file format, remove the character. The
1859 most common symbol leading character is underscore. This option will
1860 remove a leading underscore from all global symbols. This can be useful
1861 if you want to link together objects of different file formats with
1862 different conventions for symbol names. This is different from
1863 @option{--change-leading-char} because it always changes the symbol name
1864 when appropriate, regardless of the object file format of the output
1867 @item --reverse-bytes=@var{num}
1868 Reverse the bytes in a section with output contents. A section length must
1869 be evenly divisible by the value given in order for the swap to be able to
1870 take place. Reversing takes place before the interleaving is performed.
1872 This option is used typically in generating ROM images for problematic
1873 target systems. For example, on some target boards, the 32-bit words
1874 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1875 regardless of the CPU byte order. Depending on the programming model, the
1876 endianness of the ROM may need to be modified.
1878 Consider a simple file with a section containing the following eight
1879 bytes: @code{12345678}.
1881 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1882 output file would be ordered @code{21436587}.
1884 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1885 output file would be ordered @code{43218765}.
1887 By using @samp{--reverse-bytes=2} for the above example, followed by
1888 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1889 output file would be ordered @code{34127856}.
1891 @item --srec-len=@var{ival}
1892 Meaningful only for srec output. Set the maximum length of the Srecords
1893 being produced to @var{ival}. This length covers both address, data and
1896 @item --srec-forceS3
1897 Meaningful only for srec output. Avoid generation of S1/S2 records,
1898 creating S3-only record format.
1900 @item --redefine-sym @var{old}=@var{new}
1901 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1902 when one is trying link two things together for which you have no
1903 source, and there are name collisions.
1905 @item --redefine-syms=@var{filename}
1906 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1907 listed in the file @var{filename}. @var{filename} is simply a flat file,
1908 with one symbol pair per line. Line comments may be introduced by the hash
1909 character. This option may be given more than once.
1912 Change all global symbols in the file to be weak. This can be useful
1913 when building an object which will be linked against other objects using
1914 the @option{-R} option to the linker. This option is only effective when
1915 using an object file format which supports weak symbols.
1917 @item --keep-symbols=@var{filename}
1918 Apply @option{--keep-symbol} option to each symbol listed in the file
1919 @var{filename}. @var{filename} is simply a flat file, with one symbol
1920 name per line. Line comments may be introduced by the hash character.
1921 This option may be given more than once.
1923 @item --strip-symbols=@var{filename}
1924 Apply @option{--strip-symbol} option to each symbol listed in the file
1925 @var{filename}. @var{filename} is simply a flat file, with one symbol
1926 name per line. Line comments may be introduced by the hash character.
1927 This option may be given more than once.
1929 @item --strip-unneeded-symbols=@var{filename}
1930 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1931 the file @var{filename}. @var{filename} is simply a flat file, with one
1932 symbol name per line. Line comments may be introduced by the hash
1933 character. This option may be given more than once.
1935 @item --keep-global-symbols=@var{filename}
1936 Apply @option{--keep-global-symbol} option to each symbol listed in the
1937 file @var{filename}. @var{filename} is simply a flat file, with one
1938 symbol name per line. Line comments may be introduced by the hash
1939 character. This option may be given more than once.
1941 @item --localize-symbols=@var{filename}
1942 Apply @option{--localize-symbol} option to each symbol listed in the file
1943 @var{filename}. @var{filename} is simply a flat file, with one symbol
1944 name per line. Line comments may be introduced by the hash character.
1945 This option may be given more than once.
1947 @item --globalize-symbols=@var{filename}
1948 Apply @option{--globalize-symbol} option to each symbol listed in the file
1949 @var{filename}. @var{filename} is simply a flat file, with one symbol
1950 name per line. Line comments may be introduced by the hash character.
1951 This option may be given more than once. Note: this option cannot be
1952 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1955 @item --weaken-symbols=@var{filename}
1956 Apply @option{--weaken-symbol} option to each symbol listed in the file
1957 @var{filename}. @var{filename} is simply a flat file, with one symbol
1958 name per line. Line comments may be introduced by the hash character.
1959 This option may be given more than once.
1961 @item --alt-machine-code=@var{index}
1962 If the output architecture has alternate machine codes, use the
1963 @var{index}th code instead of the default one. This is useful in case
1964 a machine is assigned an official code and the tool-chain adopts the
1965 new code, but other applications still depend on the original code
1966 being used. For ELF based architectures if the @var{index}
1967 alternative does not exist then the value is treated as an absolute
1968 number to be stored in the e_machine field of the ELF header.
1970 @item --writable-text
1971 Mark the output text as writable. This option isn't meaningful for all
1972 object file formats.
1974 @item --readonly-text
1975 Make the output text write protected. This option isn't meaningful for all
1976 object file formats.
1979 Mark the output file as demand paged. This option isn't meaningful for all
1980 object file formats.
1983 Mark the output file as impure. This option isn't meaningful for all
1984 object file formats.
1986 @item --prefix-symbols=@var{string}
1987 Prefix all symbols in the output file with @var{string}.
1989 @item --prefix-sections=@var{string}
1990 Prefix all section names in the output file with @var{string}.
1992 @item --prefix-alloc-sections=@var{string}
1993 Prefix all the names of all allocated sections in the output file with
1996 @item --add-gnu-debuglink=@var{path-to-file}
1997 Creates a .gnu_debuglink section which contains a reference to
1998 @var{path-to-file} and adds it to the output file. Note: the file at
1999 @var{path-to-file} must exist. Part of the process of adding the
2000 .gnu_debuglink section involves embedding a checksum of the contents
2001 of the debug info file into the section.
2003 If the debug info file is built in one location but it is going to be
2004 installed at a later time into a different location then do not use
2005 the path to the installed location. The @option{--add-gnu-debuglink}
2006 option will fail because the installed file does not exist yet.
2007 Instead put the debug info file in the current directory and use the
2008 @option{--add-gnu-debuglink} option without any directory components,
2012 objcopy --add-gnu-debuglink=foo.debug
2015 At debug time the debugger will attempt to look for the separate debug
2016 info file in a set of known locations. The exact set of these
2017 locations varies depending upon the distribution being used, but it
2022 @item * The same directory as the executable.
2024 @item * A sub-directory of the directory containing the executable
2027 @item * A global debug directory such as /usr/lib/debug.
2030 As long as the debug info file has been installed into one of these
2031 locations before the debugger is run everything should work
2034 @item --keep-section-symbils
2035 When stripping a file, perhaps with @option{--strip-debug} or
2036 @option{--strip-unneeded}, retain any symbols specifying section names,
2037 which would otherwise get stripped.
2039 @item --keep-file-symbols
2040 When stripping a file, perhaps with @option{--strip-debug} or
2041 @option{--strip-unneeded}, retain any symbols specifying source file names,
2042 which would otherwise get stripped.
2044 @item --only-keep-debug
2045 Strip a file, removing contents of any sections that would not be
2046 stripped by @option{--strip-debug} and leaving the debugging sections
2047 intact. In ELF files, this preserves all note sections in the output.
2049 Note - the section headers of the stripped sections are preserved,
2050 including their sizes, but the contents of the section are discarded.
2051 The section headers are preserved so that other tools can match up the
2052 debuginfo file with the real executable, even if that executable has
2053 been relocated to a different address space.
2055 The intention is that this option will be used in conjunction with
2056 @option{--add-gnu-debuglink} to create a two part executable. One a
2057 stripped binary which will occupy less space in RAM and in a
2058 distribution and the second a debugging information file which is only
2059 needed if debugging abilities are required. The suggested procedure
2060 to create these files is as follows:
2063 @item Link the executable as normal. Assuming that it is called
2065 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2066 create a file containing the debugging info.
2067 @item Run @code{objcopy --strip-debug foo} to create a
2068 stripped executable.
2069 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2070 to add a link to the debugging info into the stripped executable.
2073 Note---the choice of @code{.dbg} as an extension for the debug info
2074 file is arbitrary. Also the @code{--only-keep-debug} step is
2075 optional. You could instead do this:
2078 @item Link the executable as normal.
2079 @item Copy @code{foo} to @code{foo.full}
2080 @item Run @code{objcopy --strip-debug foo}
2081 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2084 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2085 full executable. It does not have to be a file created by the
2086 @option{--only-keep-debug} switch.
2088 Note---this switch is only intended for use on fully linked files. It
2089 does not make sense to use it on object files where the debugging
2090 information may be incomplete. Besides the gnu_debuglink feature
2091 currently only supports the presence of one filename containing
2092 debugging information, not multiple filenames on a one-per-object-file
2096 Remove the contents of all DWARF .dwo sections, leaving the
2097 remaining debugging sections and all symbols intact.
2098 This option is intended for use by the compiler as part of
2099 the @option{-gsplit-dwarf} option, which splits debug information
2100 between the .o file and a separate .dwo file. The compiler
2101 generates all debug information in the same file, then uses
2102 the @option{--extract-dwo} option to copy the .dwo sections to
2103 the .dwo file, then the @option{--strip-dwo} option to remove
2104 those sections from the original .o file.
2107 Extract the contents of all DWARF .dwo sections. See the
2108 @option{--strip-dwo} option for more information.
2110 @item --file-alignment @var{num}
2111 Specify the file alignment. Sections in the file will always begin at
2112 file offsets which are multiples of this number. This defaults to
2114 [This option is specific to PE targets.]
2116 @item --heap @var{reserve}
2117 @itemx --heap @var{reserve},@var{commit}
2118 Specify the number of bytes of memory to reserve (and optionally commit)
2119 to be used as heap for this program.
2120 [This option is specific to PE targets.]
2122 @item --image-base @var{value}
2123 Use @var{value} as the base address of your program or dll. This is
2124 the lowest memory location that will be used when your program or dll
2125 is loaded. To reduce the need to relocate and improve performance of
2126 your dlls, each should have a unique base address and not overlap any
2127 other dlls. The default is 0x400000 for executables, and 0x10000000
2129 [This option is specific to PE targets.]
2131 @item --section-alignment @var{num}
2132 Sets the section alignment field in the PE header. Sections in memory
2133 will always begin at addresses which are a multiple of this number.
2135 [This option is specific to PE targets.]
2137 @item --stack @var{reserve}
2138 @itemx --stack @var{reserve},@var{commit}
2139 Specify the number of bytes of memory to reserve (and optionally commit)
2140 to be used as stack for this program.
2141 [This option is specific to PE targets.]
2143 @item --subsystem @var{which}
2144 @itemx --subsystem @var{which}:@var{major}
2145 @itemx --subsystem @var{which}:@var{major}.@var{minor}
2146 Specifies the subsystem under which your program will execute. The
2147 legal values for @var{which} are @code{native}, @code{windows},
2148 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2149 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2150 the subsystem version also. Numeric values are also accepted for
2152 [This option is specific to PE targets.]
2154 @item --extract-symbol
2155 Keep the file's section flags and symbols but remove all section data.
2156 Specifically, the option:
2159 @item removes the contents of all sections;
2160 @item sets the size of every section to zero; and
2161 @item sets the file's start address to zero.
2164 This option is used to build a @file{.sym} file for a VxWorks kernel.
2165 It can also be a useful way of reducing the size of a @option{--just-symbols}
2168 @item --compress-debug-sections
2169 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2170 ELF ABI. Note - if compression would actually make a section
2171 @emph{larger}, then it is not compressed.
2173 @item --compress-debug-sections=none
2174 @itemx --compress-debug-sections=zlib
2175 @itemx --compress-debug-sections=zlib-gnu
2176 @itemx --compress-debug-sections=zlib-gabi
2177 @itemx --compress-debug-sections=zstd
2178 For ELF files, these options control how DWARF debug sections are
2179 compressed. @option{--compress-debug-sections=none} is equivalent
2180 to @option{--decompress-debug-sections}.
2181 @option{--compress-debug-sections=zlib} and
2182 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2183 @option{--compress-debug-sections}.
2184 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug sections
2185 using the obsoleted zlib-gnu format. The debug sections are renamed to begin
2186 with @samp{.zdebug}.
2187 @option{--compress-debug-sections=zstd} compresses DWARF debug
2188 sections using zstd. Note - if compression would actually make a section
2189 @emph{larger}, then it is not compressed nor renamed.
2191 @item --decompress-debug-sections
2192 Decompress DWARF debug sections. For a @samp{.zdebug} section, the original
2195 @item --elf-stt-common=yes
2196 @itemx --elf-stt-common=no
2197 For ELF files, these options control whether common symbols should be
2198 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2199 @option{--elf-stt-common=yes} converts common symbol type to
2200 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2201 type to @code{STT_OBJECT}.
2204 @itemx --no-merge-notes
2205 For ELF files, attempt (or do not attempt) to reduce the size of any
2206 SHT_NOTE type sections by removing duplicate notes.
2210 Show the version number of @command{objcopy}.
2212 @item --verilog-data-width=@var{bytes}
2213 For Verilog output, this options controls the number of bytes
2214 converted for each output data element. The input target controls the
2215 endianness of the conversion.
2219 Verbose output: list all object files modified. In the case of
2220 archives, @samp{objcopy -V} lists all members of the archive.
2223 Show a summary of the options to @command{objcopy}.
2226 Display a list showing all architectures and object formats available.
2232 @c man begin SEEALSO objcopy
2233 ld(1), objdump(1), and the Info entries for @file{binutils}.
2240 @cindex object file information
2243 @c man title objdump display information from object files
2246 @c man begin SYNOPSIS objdump
2247 objdump [@option{-a}|@option{--archive-headers}]
2248 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2249 [@option{-C}|@option{--demangle}[=@var{style}] ]
2250 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2251 [@option{-D}|@option{--disassemble-all}]
2252 [@option{-z}|@option{--disassemble-zeroes}]
2253 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2254 [@option{-f}|@option{--file-headers}]
2255 [@option{-F}|@option{--file-offsets}]
2256 [@option{--file-start-context}]
2257 [@option{-g}|@option{--debugging}]
2258 [@option{-e}|@option{--debugging-tags}]
2259 [@option{-h}|@option{--section-headers}|@option{--headers}]
2260 [@option{-i}|@option{--info}]
2261 [@option{-j} @var{section}|@option{--section=}@var{section}]
2262 [@option{-l}|@option{--line-numbers}]
2263 [@option{-S}|@option{--source}]
2264 [@option{--source-comment}[=@var{text}]]
2265 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2266 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2267 [@option{-p}|@option{--private-headers}]
2268 [@option{-P} @var{options}|@option{--private=}@var{options}]
2269 [@option{-r}|@option{--reloc}]
2270 [@option{-R}|@option{--dynamic-reloc}]
2271 [@option{-s}|@option{--full-contents}]
2272 [@option{-Z}|@option{--decompress}]
2273 [@option{-W[lLiaprmfFsoORtUuTgAck]}|
2274 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
2275 [@option{-WK}|@option{--dwarf=follow-links}]
2276 [@option{-WN}|@option{--dwarf=no-follow-links}]
2277 [@option{-wD}|@option{--dwarf=use-debuginfod}]
2278 [@option{-wE}|@option{--dwarf=do-not-use-debuginfod}]
2279 [@option{-L}|@option{--process-links}]
2280 [@option{--ctf=}@var{section}]
2281 [@option{--sframe=}@var{section}]
2282 [@option{-G}|@option{--stabs}]
2283 [@option{-t}|@option{--syms}]
2284 [@option{-T}|@option{--dynamic-syms}]
2285 [@option{-x}|@option{--all-headers}]
2286 [@option{-w}|@option{--wide}]
2287 [@option{--start-address=}@var{address}]
2288 [@option{--stop-address=}@var{address}]
2289 [@option{--no-addresses}]
2290 [@option{--prefix-addresses}]
2291 [@option{--[no-]show-raw-insn}]
2292 [@option{--adjust-vma=}@var{offset}]
2293 [@option{--show-all-symbols}]
2294 [@option{--dwarf-depth=@var{n}}]
2295 [@option{--dwarf-start=@var{n}}]
2296 [@option{--ctf-parent=}@var{section}]
2297 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2298 [@option{--special-syms}]
2299 [@option{--prefix=}@var{prefix}]
2300 [@option{--prefix-strip=}@var{level}]
2301 [@option{--insn-width=}@var{width}]
2302 [@option{--visualize-jumps[=color|=extended-color|=off]}
2303 [@option{--disassembler-color=[off|terminal|on|extended]}
2304 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
2305 [@option{-V}|@option{--version}]
2306 [@option{-H}|@option{--help}]
2307 @var{objfile}@dots{}
2311 @c man begin DESCRIPTION objdump
2313 @command{objdump} displays information about one or more object files.
2314 The options control what particular information to display. This
2315 information is mostly useful to programmers who are working on the
2316 compilation tools, as opposed to programmers who just want their
2317 program to compile and work.
2319 @var{objfile}@dots{} are the object files to be examined. When you
2320 specify archives, @command{objdump} shows information on each of the member
2325 @c man begin OPTIONS objdump
2327 The long and short forms of options, shown here as alternatives, are
2328 equivalent. At least one option from the list
2329 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2333 @itemx --archive-header
2334 @cindex archive headers
2335 If any of the @var{objfile} files are archives, display the archive
2336 header information (in a format similar to @samp{ls -l}). Besides the
2337 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2338 the object file format of each archive member.
2340 @item --adjust-vma=@var{offset}
2341 @cindex section addresses in objdump
2342 @cindex VMA in objdump
2343 When dumping information, first add @var{offset} to all the section
2344 addresses. This is useful if the section addresses do not correspond to
2345 the symbol table, which can happen when putting sections at particular
2346 addresses when using a format which can not represent section addresses,
2349 @item -b @var{bfdname}
2350 @itemx --target=@var{bfdname}
2351 @cindex object code format
2352 Specify that the object-code format for the object files is
2353 @var{bfdname}. This option may not be necessary; @var{objdump} can
2354 automatically recognize many formats.
2358 objdump -b oasys -m vax -h fu.o
2361 displays summary information from the section headers (@option{-h}) of
2362 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2363 file in the format produced by Oasys compilers. You can list the
2364 formats available with the @option{-i} option.
2365 @xref{Target Selection}, for more information.
2368 @itemx --demangle[=@var{style}]
2369 @cindex demangling in objdump
2370 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2371 Besides removing any initial underscore prepended by the system, this
2372 makes C++ function names readable. Different compilers have different
2373 mangling styles. The optional demangling style argument can be used to
2374 choose an appropriate demangling style for your compiler. @xref{c++filt},
2375 for more information on demangling.
2377 @item --recurse-limit
2378 @itemx --no-recurse-limit
2379 @itemx --recursion-limit
2380 @itemx --no-recursion-limit
2381 Enables or disables a limit on the amount of recursion performed
2382 whilst demangling strings. Since the name mangling formats allow for
2383 an infinite level of recursion it is possible to create strings whose
2384 decoding will exhaust the amount of stack space available on the host
2385 machine, triggering a memory fault. The limit tries to prevent this
2386 from happening by restricting recursion to 2048 levels of nesting.
2388 The default is for this limit to be enabled, but disabling it may be
2389 necessary in order to demangle truly complicated names. Note however
2390 that if the recursion limit is disabled then stack exhaustion is
2391 possible and any bug reports about such an event will be rejected.
2395 Display debugging information. This attempts to parse STABS
2396 debugging format information stored in the file and print it out using
2397 a C like syntax. If no STABS debugging was found this option
2398 falls back on the @option{-W} option to print any DWARF information in
2402 @itemx --debugging-tags
2403 Like @option{-g}, but the information is generated in a format compatible
2407 @itemx --disassemble
2408 @itemx --disassemble=@var{symbol}
2409 @cindex disassembling object code
2410 @cindex machine instructions
2411 Display the assembler mnemonics for the machine instructions from the
2412 input file. This option only disassembles those sections which are
2413 expected to contain instructions. If the optional @var{symbol}
2414 argument is given, then display the assembler mnemonics starting at
2415 @var{symbol}. If @var{symbol} is a function name then disassembly
2416 will stop at the end of the function, otherwise it will stop when the
2417 next symbol is encountered. If there are no matches for @var{symbol}
2418 then nothing will be displayed.
2420 Note if the @option{--dwarf=follow-links} option is enabled
2421 then any symbol tables in linked debug info files will be read in and
2422 used when disassembling.
2425 @itemx --disassemble-all
2426 Like @option{-d}, but disassemble the contents of all non-empty
2427 non-bss sections, not just those expected to contain instructions.
2428 @option{-j} may be used to select specific sections.
2430 This option also has a subtle effect on the disassembly of
2431 instructions in code sections. When option @option{-d} is in effect
2432 objdump will assume that any symbols present in a code section occur
2433 on the boundary between instructions and it will refuse to disassemble
2434 across such a boundary. When option @option{-D} is in effect however
2435 this assumption is supressed. This means that it is possible for the
2436 output of @option{-d} and @option{-D} to differ if, for example, data
2437 is stored in code sections.
2439 If the target is an ARM architecture this switch also has the effect
2440 of forcing the disassembler to decode pieces of data found in code
2441 sections as if they were instructions.
2443 Note if the @option{--dwarf=follow-links} option is enabled
2444 then any symbol tables in linked debug info files will be read in and
2445 used when disassembling.
2447 @item --no-addresses
2448 When disassembling, don't print addresses on each line or for symbols
2449 and relocation offsets. In combination with @option{--no-show-raw-insn}
2450 this may be useful for comparing compiler output.
2452 @item --prefix-addresses
2453 When disassembling, print the complete address on each line. This is
2454 the older disassembly format.
2458 @itemx --endian=@{big|little@}
2460 @cindex disassembly endianness
2461 Specify the endianness of the object files. This only affects
2462 disassembly. This can be useful when disassembling a file format which
2463 does not describe endianness information, such as S-records.
2466 @itemx --file-headers
2467 @cindex object file header
2468 Display summary information from the overall header of
2469 each of the @var{objfile} files.
2472 @itemx --file-offsets
2473 @cindex object file offsets
2474 When disassembling sections, whenever a symbol is displayed, also
2475 display the file offset of the region of data that is about to be
2476 dumped. If zeroes are being skipped, then when disassembly resumes,
2477 tell the user how many zeroes were skipped and the file offset of the
2478 location from where the disassembly resumes. When dumping sections,
2479 display the file offset of the location from where the dump starts.
2481 @item --file-start-context
2482 @cindex source code context
2483 Specify that when displaying interlisted source code/disassembly
2484 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2485 context to the start of the file.
2488 @itemx --section-headers
2490 @cindex section headers
2491 Display summary information from the section headers of the
2494 File segments may be relocated to nonstandard addresses, for example by
2495 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2496 @command{ld}. However, some object file formats, such as a.out, do not
2497 store the starting address of the file segments. In those situations,
2498 although @command{ld} relocates the sections correctly, using @samp{objdump
2499 -h} to list the file section headers cannot show the correct addresses.
2500 Instead, it shows the usual addresses, which are implicit for the
2503 Note, in some cases it is possible for a section to have both the
2504 READONLY and the NOREAD attributes set. In such cases the NOREAD
2505 attribute takes precedence, but @command{objdump} will report both
2506 since the exact setting of the flag bits might be important.
2510 Print a summary of the options to @command{objdump} and exit.
2514 @cindex architectures available
2515 @cindex object formats available
2516 Display a list showing all architectures and object formats available
2517 for specification with @option{-b} or @option{-m}.
2520 @itemx --section=@var{name}
2521 @cindex section information
2522 Display information for section @var{name}. This option may be
2523 specified multiple times.
2526 @itemx --process-links
2527 Display the contents of non-debug sections found in separate debuginfo
2528 files that are linked to the main file. This option automatically
2529 implies the @option{-WK} option, and only sections requested by other
2530 command line options will be displayed.
2533 @itemx --line-numbers
2534 @cindex source filenames for object files
2535 Label the display (using debugging information) with the filename and
2536 source line numbers corresponding to the object code or relocs shown.
2537 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2539 @item -m @var{machine}
2540 @itemx --architecture=@var{machine}
2541 @cindex architecture
2542 @cindex disassembly architecture
2543 Specify the architecture to use when disassembling object files. This
2544 can be useful when disassembling object files which do not describe
2545 architecture information, such as S-records. You can list the available
2546 architectures with the @option{-i} option.
2548 For most architectures it is possible to supply an architecture
2549 name and a machine name, separated by a colon. For example
2550 @samp{foo:bar} would refer to the @samp{bar} machine type in the
2551 @samp{foo} architecture. This can be helpful if objdump has been
2552 configured to support multiple architectures.
2554 If the target is an ARM architecture then this switch has an
2555 additional effect. It restricts the disassembly to only those
2556 instructions supported by the architecture specified by @var{machine}.
2557 If it is necessary to use this switch because the input file does not
2558 contain any architecture information, but it is also desired to
2559 disassemble all the instructions use @option{-marm}.
2561 @item -M @var{options}
2562 @itemx --disassembler-options=@var{options}
2563 Pass target specific information to the disassembler. Only supported on
2564 some targets. If it is necessary to specify more than one
2565 disassembler option then multiple @option{-M} options can be used or
2566 can be placed together into a comma separated list.
2568 For ARC, @option{dsp} controls the printing of DSP instructions,
2569 @option{spfp} selects the printing of FPX single precision FP
2570 instructions, @option{dpfp} selects the printing of FPX double
2571 precision FP instructions, @option{quarkse_em} selects the printing of
2572 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2573 of double precision assist instructions, @option{fpus} selects the
2574 printing of FPU single precision FP instructions, while @option{fpud}
2575 selects the printing of FPU double precision FP instructions.
2576 Additionally, one can choose to have all the immediates printed in
2577 hexadecimal using @option{hex}. By default, the short immediates are
2578 printed using the decimal representation, while the long immediate
2579 values are printed as hexadecimal.
2581 @option{cpu=...} allows one to enforce a particular ISA when disassembling
2582 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2583 This might be useful to select ARC EM or HS ISA, because architecture is same
2584 for those and disassembler relies on private ELF header data to decide if code
2585 is for EM or HS. This option might be specified multiple times - only the
2586 latest value will be used. Valid values are same as for the assembler
2587 @option{-mcpu=...} option.
2589 If the target is an ARM architecture then this switch can be used to
2590 select which register name set is used during disassembler. Specifying
2591 @option{-M reg-names-std} (the default) will select the register names as
2592 used in ARM's instruction set documentation, but with register 13 called
2593 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2594 @option{-M reg-names-apcs} will select the name set used by the ARM
2595 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2596 just use @samp{r} followed by the register number.
2598 There are also two variants on the APCS register naming scheme enabled
2599 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2600 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2601 with the normal register names or the special register names).
2603 This option can also be used for ARM architectures to force the
2604 disassembler to interpret all instructions as Thumb instructions by
2605 using the switch @option{--disassembler-options=force-thumb}. This can be
2606 useful when attempting to disassemble thumb code produced by other
2609 For AArch64 targets this switch can be used to set whether instructions are
2610 disassembled as the most general instruction using the @option{-M no-aliases}
2611 option or whether instruction notes should be generated as comments in the
2612 disasssembly using @option{-M notes}.
2614 For the x86, some of the options duplicate functions of the @option{-m}
2615 switch, but allow finer grained control.
2620 Select disassembly for the given architecture.
2624 Select between intel syntax mode and AT&T syntax mode.
2628 Select between AMD64 ISA and Intel64 ISA.
2630 @item intel-mnemonic
2632 Select between intel mnemonic mode and AT&T mnemonic mode.
2633 Note: @code{intel-mnemonic} implies @code{intel} and
2634 @code{att-mnemonic} implies @code{att}.
2641 Specify the default address size and operand size. These five options
2642 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2643 appear later in the option string.
2646 When in AT&T mode and also for a limited set of instructions when in Intel
2647 mode, instructs the disassembler to print a mnemonic suffix even when the
2648 suffix could be inferred by the operands or, for certain instructions, the
2649 execution mode's defaults.
2652 For PowerPC, the @option{-M} argument @option{raw} selects
2653 disasssembly of hardware insns rather than aliases. For example, you
2654 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2655 rather than @code{li}. All of the @option{-m} arguments for
2656 @command{gas} that select a CPU are supported. These are:
2657 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2658 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2659 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2660 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2661 @option{booke32}, @option{cell}, @option{com}, @option{e200z2}, @option{e200z4},
2662 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2663 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2664 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2665 @option{power8}, @option{power9}, @option{power10}, @option{ppc},
2666 @option{ppc32}, @option{ppc64}, @option{ppc64bridge}, @option{ppcps},
2667 @option{pwr}, @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2668 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9}, @option{pwr10},
2669 @option{pwrx}, @option{titan}, @option{vle}, and @option{future}.
2670 @option{32} and @option{64} modify the default or a prior CPU
2671 selection, disabling and enabling 64-bit insns respectively. In
2672 addition, @option{altivec}, @option{any}, @option{lsp}, @option{htm},
2673 @option{vsx}, @option{spe} and @option{spe2} add capabilities to a
2674 previous @emph{or later} CPU selection.
2675 @option{any} will disassemble any opcode known to
2676 binutils, but in cases where an opcode has two different meanings or
2677 different arguments, you may not see the disassembly you expect.
2678 If you disassemble without giving a CPU selection, a default will be
2679 chosen from information gleaned by BFD from the object files headers,
2680 but the result again may not be as you expect.
2682 For MIPS, this option controls the printing of instruction mnemonic
2683 names and register names in disassembled instructions. Multiple
2684 selections from the following may be specified as a comma separated
2685 string, and invalid options are ignored:
2689 Print the 'raw' instruction mnemonic instead of some pseudo
2690 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2691 'sll' instead of 'nop', etc.
2694 Disassemble MSA instructions.
2697 Disassemble the virtualization ASE instructions.
2700 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2702 @item gpr-names=@var{ABI}
2703 Print GPR (general-purpose register) names as appropriate
2704 for the specified ABI. By default, GPR names are selected according to
2705 the ABI of the binary being disassembled.
2707 @item fpr-names=@var{ABI}
2708 Print FPR (floating-point register) names as
2709 appropriate for the specified ABI. By default, FPR numbers are printed
2712 @item cp0-names=@var{ARCH}
2713 Print CP0 (system control coprocessor; coprocessor 0) register names
2714 as appropriate for the CPU or architecture specified by
2715 @var{ARCH}. By default, CP0 register names are selected according to
2716 the architecture and CPU of the binary being disassembled.
2718 @item hwr-names=@var{ARCH}
2719 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2720 as appropriate for the CPU or architecture specified by
2721 @var{ARCH}. By default, HWR names are selected according to
2722 the architecture and CPU of the binary being disassembled.
2724 @item reg-names=@var{ABI}
2725 Print GPR and FPR names as appropriate for the selected ABI.
2727 @item reg-names=@var{ARCH}
2728 Print CPU-specific register names (CP0 register and HWR names)
2729 as appropriate for the selected CPU or architecture.
2732 For any of the options listed above, @var{ABI} or
2733 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2734 rather than names, for the selected types of registers.
2735 You can list the available values of @var{ABI} and @var{ARCH} using
2736 the @option{--help} option.
2738 For VAX, you can specify function entry addresses with @option{-M
2739 entry:0xf00ba}. You can use this multiple times to properly
2740 disassemble VAX binary files that don't contain symbol tables (like
2741 ROM dumps). In these cases, the function entry mask would otherwise
2742 be decoded as VAX instructions, which would probably lead the rest
2743 of the function being wrongly disassembled.
2746 @itemx --private-headers
2747 Print information that is specific to the object file format. The exact
2748 information printed depends upon the object file format. For some
2749 object file formats, no additional information is printed.
2751 @item -P @var{options}
2752 @itemx --private=@var{options}
2753 Print information that is specific to the object file format. The
2754 argument @var{options} is a comma separated list that depends on the
2755 format (the lists of options is displayed with the help).
2757 For XCOFF, the available options are:
2773 For PE, the available options are:
2779 Not all object formats support this option. In particular the ELF
2780 format does not use it.
2784 @cindex relocation entries, in object file
2785 Print the relocation entries of the file. If used with @option{-d} or
2786 @option{-D}, the relocations are printed interspersed with the
2790 @itemx --dynamic-reloc
2791 @cindex dynamic relocation entries, in object file
2792 Print the dynamic relocation entries of the file. This is only
2793 meaningful for dynamic objects, such as certain types of shared
2794 libraries. As for @option{-r}, if used with @option{-d} or
2795 @option{-D}, the relocations are printed interspersed with the
2799 @itemx --full-contents
2800 @cindex sections, full contents
2801 @cindex object file sections
2802 Display the full contents of sections, often used in combination with
2803 @option{-j} to request specific sections. By default all non-empty
2804 non-bss sections are displayed. By default any compressed section
2805 will be displayed in its compressed form. In order to see the
2806 contents in a decompressed form add the @option{-Z} option to the
2811 @cindex source disassembly
2812 @cindex disassembly, with source
2813 Display source code intermixed with disassembly, if possible. Implies
2816 @item --show-all-symbols
2817 When disassembling, show all the symbols that match a given address,
2818 not just the first one.
2820 @item --source-comment[=@var{txt}]
2821 @cindex source disassembly
2822 @cindex disassembly, with source
2823 Like the @option{-S} option, but all source code lines are displayed
2824 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2825 string which can be used to distinguish the assembler code from the
2826 source code. If @var{txt} is not provided then a default string of
2827 @var{``# ``} (hash followed by a space), will be used.
2829 @item --prefix=@var{prefix}
2830 @cindex Add prefix to absolute paths
2831 Specify @var{prefix} to add to the absolute paths when used with
2834 @item --prefix-strip=@var{level}
2835 @cindex Strip absolute paths
2836 Indicate how many initial directory names to strip off the hardwired
2837 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2839 @item --show-raw-insn
2840 When disassembling instructions, print the instruction in hex as well as
2841 in symbolic form. This is the default except when
2842 @option{--prefix-addresses} is used.
2844 @item --no-show-raw-insn
2845 When disassembling instructions, do not print the instruction bytes.
2846 This is the default when @option{--prefix-addresses} is used.
2848 @item --insn-width=@var{width}
2849 @cindex Instruction width
2850 Display @var{width} bytes on a single line when disassembling
2853 @item --visualize-jumps[=color|=extended-color|=off]
2854 Visualize jumps that stay inside a function by drawing ASCII art between
2855 the start and target addresses. The optional @option{=color} argument
2856 adds color to the output using simple terminal colors. Alternatively
2857 the @option{=extended-color} argument will add color using 8bit
2858 colors, but these might not work on all terminals.
2860 If it is necessary to disable the @option{visualize-jumps} option
2861 after it has previously been enabled then use
2862 @option{visualize-jumps=off}.
2864 @item --disassembler-color=off
2865 @itemx --disassembler-color=terminal
2866 @itemx --disassembler-color=on|color|colour
2867 @itemx --disassembler-color=extened|extended-color|extened-colour
2868 Enables or disables the use of colored syntax highlighting in
2869 disassembly output. The default behaviour is determined via a
2870 configure time option. Note, not all architectures support colored
2871 syntax highlighting, and depending upon the terminal used, colored
2872 output may not actually be legible.
2874 The @option{on} argument adds colors using simple terminal colors.
2876 The @option{terminal} argument does the same, but only if the output
2877 device is a terminal.
2879 The @option{extended-color} argument is similar to the @option{on}
2880 argument, but it uses 8-bit colors. These may not work on all
2883 The @option{off} argument disables colored disassembly.
2885 @item -W[lLiaprmfFsoORtUuTgAckK]
2886 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
2887 @include debug.options.texi
2890 Enable additional checks for consistency of Dwarf information.
2892 @include ctf.options.texi
2894 @include sframe.options.texi
2900 @cindex debug symbols
2901 @cindex ELF object file format
2902 Display the full contents of any sections requested. Display the
2903 contents of the .stab and .stab.index and .stab.excl sections from an
2904 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2905 @code{.stab} debugging symbol-table entries are carried in an ELF
2906 section. In most other file formats, debugging symbol-table entries are
2907 interleaved with linkage symbols, and are visible in the @option{--syms}
2910 @item --start-address=@var{address}
2911 @cindex start-address
2912 Start displaying data at the specified address. This affects the output
2913 of the @option{-d}, @option{-r} and @option{-s} options.
2915 @item --stop-address=@var{address}
2916 @cindex stop-address
2917 Stop displaying data at the specified address. This affects the output
2918 of the @option{-d}, @option{-r} and @option{-s} options.
2922 @cindex symbol table entries, printing
2923 Print the symbol table entries of the file.
2924 This is similar to the information provided by the @samp{nm} program,
2925 although the display format is different. The format of the output
2926 depends upon the format of the file being dumped, but there are two main
2927 types. One looks like this:
2930 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2931 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2934 where the number inside the square brackets is the number of the entry
2935 in the symbol table, the @var{sec} number is the section number, the
2936 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2937 symbol's type, the @var{scl} number is the symbol's storage class and
2938 the @var{nx} value is the number of auxiliary entries associated with
2939 the symbol. The last two fields are the symbol's value and its name.
2941 The other common output format, usually seen with ELF based files,
2945 00000000 l d .bss 00000000 .bss
2946 00000000 g .text 00000000 fred
2949 Here the first number is the symbol's value (sometimes referred to as
2950 its address). The next field is actually a set of characters and
2951 spaces indicating the flag bits that are set on the symbol. These
2952 characters are described below. Next is the section with which the
2953 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2954 not connected with any section), or @emph{*UND*} if the section is
2955 referenced in the file being dumped, but not defined there.
2957 After the section name comes another field, a number, which for common
2958 symbols is the alignment and for other symbol is the size. Finally
2959 the symbol's name is displayed.
2961 The flag characters are divided into 7 groups as follows:
2967 The symbol is a local (l), global (g), unique global (u), neither
2968 global nor local (a space) or both global and local (!). A
2969 symbol can be neither local or global for a variety of reasons, e.g.,
2970 because it is used for debugging, but it is probably an indication of
2971 a bug if it is ever both local and global. Unique global symbols are
2972 a GNU extension to the standard set of ELF symbol bindings. For such
2973 a symbol the dynamic linker will make sure that in the entire process
2974 there is just one symbol with this name and type in use.
2977 The symbol is weak (w) or strong (a space).
2980 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2983 The symbol is a warning (W) or a normal symbol (a space). A warning
2984 symbol's name is a message to be displayed if the symbol following the
2985 warning symbol is ever referenced.
2989 The symbol is an indirect reference to another symbol (I), a function
2990 to be evaluated during reloc processing (i) or a normal symbol (a
2995 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2996 normal symbol (a space).
3001 The symbol is the name of a function (F) or a file (f) or an object
3002 (O) or just a normal symbol (a space).
3006 @itemx --dynamic-syms
3007 @cindex dynamic symbol table entries, printing
3008 Print the dynamic symbol table entries of the file. This is only
3009 meaningful for dynamic objects, such as certain types of shared
3010 libraries. This is similar to the information provided by the @samp{nm}
3011 program when given the @option{-D} (@option{--dynamic}) option.
3013 The output format is similar to that produced by the @option{--syms}
3014 option, except that an extra field is inserted before the symbol's
3015 name, giving the version information associated with the symbol.
3016 If the version is the default version to be used when resolving
3017 unversioned references to the symbol then it's displayed as is,
3018 otherwise it's put into parentheses.
3020 @item --special-syms
3021 When displaying symbols include those which the target considers to be
3022 special in some way and which would not normally be of interest to the
3025 @item -U @var{[d|i|l|e|x|h]}
3026 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3027 Controls the display of UTF-8 encoded multibyte characters in strings.
3028 The default (@option{--unicode=default}) is to give them no special
3029 treatment. The @option{--unicode=locale} option displays the sequence
3030 in the current locale, which may or may not support them. The options
3031 @option{--unicode=hex} and @option{--unicode=invalid} display them as
3032 hex byte sequences enclosed by either angle brackets or curly braces.
3034 The @option{--unicode=escape} option displays them as escape sequences
3035 (@var{\uxxxx}) and the @option{--unicode=highlight} option displays
3036 them as escape sequences highlighted in red (if supported by the
3037 output device). The colouring is intended to draw attention to the
3038 presence of unicode sequences where they might not be expected.
3042 Print the version number of @command{objdump} and exit.
3045 @itemx --all-headers
3046 @cindex all header information, object file
3047 @cindex header information, all
3048 Display all available header information, including the symbol table and
3049 relocation entries. Using @option{-x} is equivalent to specifying all of
3050 @option{-a -f -h -p -r -t}.
3054 @cindex wide output, printing
3055 Format some lines for output devices that have more than 80 columns.
3056 Also do not truncate symbol names when they are displayed.
3059 @itemx --disassemble-zeroes
3060 Normally the disassembly output will skip blocks of zeroes. This
3061 option directs the disassembler to disassemble those blocks, just like
3066 @cindex sections, full contents
3067 @cindex object file sections
3068 @cindex compressed section contents
3069 The @option{-Z} option is meant to be used in conunction with the
3070 @option{-s} option. It instructs @command{objdump} to decompress any
3071 compressed sections before displaying their contents.
3077 @c man begin SEEALSO objdump
3078 nm(1), readelf(1), and the Info entries for @file{binutils}.
3086 @cindex archive contents
3087 @cindex symbol index
3089 @c man title ranlib generate an index to an archive
3092 @c man begin SYNOPSIS ranlib
3093 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
3097 @c man begin DESCRIPTION ranlib
3099 @command{ranlib} generates an index to the contents of an archive and
3100 stores it in the archive. The index lists each symbol defined by a
3101 member of an archive that is a relocatable object file.
3103 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
3105 An archive with such an index speeds up linking to the library and
3106 allows routines in the library to call each other without regard to
3107 their placement in the archive.
3109 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
3110 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
3115 @c man begin OPTIONS ranlib
3121 Show usage information for @command{ranlib}.
3126 Show the version number of @command{ranlib}.
3129 @cindex deterministic archives
3130 @kindex --enable-deterministic-archives
3131 Operate in @emph{deterministic} mode. The symbol map archive member's
3132 header will show zero for the UID, GID, and timestamp. When this
3133 option is used, multiple runs will produce identical output files.
3135 If @file{binutils} was configured with
3136 @option{--enable-deterministic-archives}, then this mode is on by
3137 default. It can be disabled with the @samp{-U} option, described
3141 Update the timestamp of the symbol map of an archive.
3144 @cindex deterministic archives
3145 @kindex --enable-deterministic-archives
3146 Do @emph{not} operate in @emph{deterministic} mode. This is the
3147 inverse of the @samp{-D} option, above: the archive index will get
3148 actual UID, GID, timestamp, and file mode values.
3150 If @file{binutils} was configured @emph{without}
3151 @option{--enable-deterministic-archives}, then this mode is on by
3159 @c man begin SEEALSO ranlib
3160 ar(1), nm(1), and the Info entries for @file{binutils}.
3168 @cindex section sizes
3170 @c man title size list section sizes and total size of binary files
3173 @c man begin SYNOPSIS size
3174 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
3176 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
3178 [@option{-t}|@option{--totals}]
3179 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
3181 [@var{objfile}@dots{}]
3185 @c man begin DESCRIPTION size
3187 The @sc{gnu} @command{size} utility lists the section sizes and the total
3188 size for each of the binary files @var{objfile} on its argument list.
3189 By default, one line of output is generated for each file or each
3190 module if the file is an archive.
3192 @var{objfile}@dots{} are the files to be examined. If none are
3193 specified, the file @code{a.out} will be used instead.
3197 @c man begin OPTIONS size
3199 The command-line options have the following meanings:
3205 @itemx --format=@var{compatibility}
3206 @cindex @command{size} display format
3207 Using one of these options, you can choose whether the output from @sc{gnu}
3208 @command{size} resembles output from System V @command{size} (using @option{-A},
3209 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
3210 @option{--format=berkeley}). The default is the one-line format similar to
3211 Berkeley's. Alternatively, you can choose the GNU format output
3212 (using @option{-G}, or @option{--format=gnu}), this is similar to
3213 Berkeley's output format, but sizes are counted differently.
3214 @c Bonus for doc-source readers: you can also say --format=strange (or
3215 @c anything else that starts with 's') for sysv, and --format=boring (or
3216 @c anything else that starts with 'b') for Berkeley.
3218 Here is an example of the Berkeley (default) format of output from
3221 $ size --format=Berkeley ranlib size
3222 text data bss dec hex filename
3223 294880 81920 11592 388392 5ed28 ranlib
3224 294880 81920 11888 388688 5ee50 size
3227 The Berkeley style output counts read only data in the @code{text}
3228 column, not in the @code{data} column, the @code{dec} and @code{hex}
3229 columns both display the sum of the @code{text}, @code{data}, and
3230 @code{bss} columns in decimal and hexadecimal respectively.
3232 The GNU format counts read only data in the @code{data} column, not
3233 the @code{text} column, and only displays the sum of the @code{text},
3234 @code{data}, and @code{bss} columns once, in the @code{total} column.
3235 The @option{--radix} option can be used to change the number base for
3236 all columns. Here is the same data displayed with GNU conventions:
3239 $ size --format=GNU ranlib size
3240 text data bss total filename
3241 279880 96920 11592 388392 ranlib
3242 279880 96920 11888 388688 size
3246 This is the same data, but displayed closer to System V conventions:
3249 $ size --format=SysV ranlib size
3270 Show a summary of acceptable arguments and options.
3275 @itemx --radix=@var{number}
3276 @cindex @command{size} number format
3277 @cindex radix for section sizes
3278 Using one of these options, you can control whether the size of each
3279 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3280 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3281 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3282 values (8, 10, 16) are supported. The total size is always given in two
3283 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3284 octal and hexadecimal if you're using @option{-o}.
3287 Print total size of common symbols in each file. When using Berkeley
3288 or GNU format these are included in the bss size.
3292 Show totals of all objects listed (Berkeley or GNU format mode only).
3294 @item --target=@var{bfdname}
3295 @cindex object code format
3296 Specify that the object-code format for @var{objfile} is
3297 @var{bfdname}. This option may not be necessary; @command{size} can
3298 automatically recognize many formats.
3299 @xref{Target Selection}, for more information.
3304 Display the version number of @command{size}.
3307 Ignored. This option is used by other versions of the @command{size}
3308 program, but it is not supported by the GNU Binutils version.
3315 @c man begin SEEALSO size
3316 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3323 @cindex listings strings
3324 @cindex printing strings
3325 @cindex strings, printing
3327 @c man title strings print the sequences of printable characters in files
3330 @c man begin SYNOPSIS strings
3331 strings [@option{-afovV}] [@option{-}@var{min-len}]
3332 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3333 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3334 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3335 [@option{-U} @var{method}] [@option{--unicode=}@var{method}]
3336 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3337 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3338 [@option{-w}] [@option{--include-all-whitespace}]
3339 [@option{-s}] [@option{--output-separator} @var{sep_string}]
3340 [@option{--help}] [@option{--version}] @var{file}@dots{}
3344 @c man begin DESCRIPTION strings
3346 For each @var{file} given, @sc{gnu} @command{strings} prints the
3347 printable character sequences that are at least 4 characters long (or
3348 the number given with the options below) and are followed by an
3349 unprintable character.
3351 Depending upon how the strings program was configured it will default
3352 to either displaying all the printable sequences that it can find in
3353 each file, or only those sequences that are in loadable, initialized
3354 data sections. If the file type is unrecognizable, or if strings is
3355 reading from stdin then it will always display all of the printable
3356 sequences that it can find.
3358 For backwards compatibility any file that occurs after a command-line
3359 option of just @option{-} will also be scanned in full, regardless of
3360 the presence of any @option{-d} option.
3362 @command{strings} is mainly useful for determining the contents of
3367 @c man begin OPTIONS strings
3373 Scan the whole file, regardless of what sections it contains or
3374 whether those sections are loaded or initialized. Normally this is
3375 the default behaviour, but strings can be configured so that the
3376 @option{-d} is the default instead.
3378 The @option{-} option is position dependent and forces strings to
3379 perform full scans of any file that is mentioned after the @option{-}
3380 on the command line, even if the @option{-d} option has been
3385 Only print strings from initialized, loaded data sections in the
3386 file. This may reduce the amount of garbage in the output, but it
3387 also exposes the strings program to any security flaws that may be
3388 present in the BFD library used to scan and load sections. Strings
3389 can be configured so that this option is the default behaviour. In
3390 such cases the @option{-a} option can be used to avoid using the BFD
3391 library and instead just print all of the strings found in the file.
3394 @itemx --print-file-name
3395 Print the name of the file before each string.
3398 Print a summary of the program usage on the standard output and exit.
3400 @item -@var{min-len}
3401 @itemx -n @var{min-len}
3402 @itemx --bytes=@var{min-len}
3403 Print sequences of displayable characters that are at least
3404 @var{min-len} characters long. If not specified a default minimum
3405 length of 4 is used. The distinction between displayable and
3406 non-displayable characters depends upon the setting of the
3407 @option{-e} and @option{-U} options. Sequences are always terminated
3408 at control characters such as new-line and carriage-return, but not
3412 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3413 act like @samp{-t d} instead. Since we can not be compatible with both
3414 ways, we simply chose one.
3416 @item -t @var{radix}
3417 @itemx --radix=@var{radix}
3418 Print the offset within the file before each string. The single
3419 character argument specifies the radix of the offset---@samp{o} for
3420 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3422 @item -e @var{encoding}
3423 @itemx --encoding=@var{encoding}
3424 Select the character encoding of the strings that are to be found.
3425 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3426 characters (default), @samp{S} =
3427 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3428 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3429 littleendian. Useful for finding wide character strings. (@samp{l}
3430 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3432 @item -U @var{[d|i|l|e|x|h]}
3433 @itemx --unicode=@var{[default|invalid|locale|escape|hex|highlight]}
3434 Controls the display of UTF-8 encoded multibyte characters in strings.
3435 The default (@option{--unicode=default}) is to give them no special
3436 treatment, and instead rely upon the setting of the
3437 @option{--encoding} option. The other values for this option
3438 automatically enable @option{--encoding=S}.
3440 The @option{--unicode=invalid} option treats them as non-graphic
3441 characters and hence not part of a valid string. All the remaining
3442 options treat them as valid string characters.
3444 The @option{--unicode=locale} option displays them in the current
3445 locale, which may or may not support UTF-8 encoding. The
3446 @option{--unicode=hex} option displays them as hex byte sequences
3447 enclosed between @var{<>} characters. The @option{--unicode=escape}
3448 option displays them as escape sequences (@var{\uxxxx}) and the
3449 @option{--unicode=highlight} option displays them as escape sequences
3450 highlighted in red (if supported by the output device). The colouring
3451 is intended to draw attention to the presence of unicode sequences
3452 where they might not be expected.
3454 @item -T @var{bfdname}
3455 @itemx --target=@var{bfdname}
3456 @cindex object code format
3457 Specify an object code format other than your system's default format.
3458 @xref{Target Selection}, for more information.
3463 Print the program version number on the standard output and exit.
3466 @itemx --include-all-whitespace
3467 By default tab and space characters are included in the strings that
3468 are displayed, but other whitespace characters, such a newlines and
3469 carriage returns, are not. The @option{-w} option changes this so
3470 that all whitespace characters are considered to be part of a string.
3473 @itemx --output-separator
3474 By default, output strings are delimited by a new-line. This option
3475 allows you to supply any string to be used as the output record
3476 separator. Useful with --include-all-whitespace where strings
3477 may contain new-lines internally.
3483 @c man begin SEEALSO strings
3484 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3485 and the Info entries for @file{binutils}.
3493 @cindex removing symbols
3494 @cindex discarding symbols
3495 @cindex symbols, discarding
3497 @c man title strip discard symbols and other data from object files
3500 @c man begin SYNOPSIS strip
3501 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3502 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3503 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3504 [@option{-s}|@option{--strip-all}]
3505 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3506 [@option{--strip-dwo}]
3507 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3508 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3509 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3510 [@option{-w}|@option{--wildcard}]
3511 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3512 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3513 [@option{--keep-section=}@var{sectionpattern}]
3514 [@option{--remove-relocations=}@var{sectionpattern}]
3515 [@option{--strip-section-headers}]
3516 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3517 [@option{-D}|@option{--enable-deterministic-archives}]
3518 [@option{-U}|@option{--disable-deterministic-archives}]
3519 [@option{--keep-section-symbols}]
3520 [@option{--keep-file-symbols}]
3521 [@option{--only-keep-debug}]
3522 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3523 [@option{--help}] [@option{--info}]
3524 @var{objfile}@dots{}
3528 @c man begin DESCRIPTION strip
3530 @sc{gnu} @command{strip} discards all symbols from object files
3531 @var{objfile}. The list of object files may include archives.
3532 At least one object file must be given.
3534 @command{strip} modifies the files named in its argument,
3535 rather than writing modified copies under different names.
3539 @c man begin OPTIONS strip
3542 @item -F @var{bfdname}
3543 @itemx --target=@var{bfdname}
3544 Treat the original @var{objfile} as a file with the object
3545 code format @var{bfdname}, and rewrite it in the same format.
3546 @xref{Target Selection}, for more information.
3549 Show a summary of the options to @command{strip} and exit.
3552 Display a list showing all architectures and object formats available.
3554 @item -I @var{bfdname}
3555 @itemx --input-target=@var{bfdname}
3556 Treat the original @var{objfile} as a file with the object
3557 code format @var{bfdname}.
3558 @xref{Target Selection}, for more information.
3560 @item -O @var{bfdname}
3561 @itemx --output-target=@var{bfdname}
3562 Replace @var{objfile} with a file in the output format @var{bfdname}.
3563 @xref{Target Selection}, for more information.
3565 @item -R @var{sectionname}
3566 @itemx --remove-section=@var{sectionname}
3567 Remove any section named @var{sectionname} from the output file, in
3568 addition to whatever sections would otherwise be removed. This
3569 option may be given more than once. Note that using this option
3570 inappropriately may make the output file unusable. The wildcard
3571 character @samp{*} may be given at the end of @var{sectionname}. If
3572 so, then any section starting with @var{sectionname} will be removed.
3574 If the first character of @var{sectionpattern} is the exclamation
3575 point (!) then matching sections will not be removed even if an
3576 earlier use of @option{--remove-section} on the same command line
3577 would otherwise remove it. For example:
3580 --remove-section=.text.* --remove-section=!.text.foo
3583 will remove all sections matching the pattern '.text.*', but will not
3584 remove the section '.text.foo'.
3586 @item --keep-section=@var{sectionpattern}
3587 When removing sections from the output file, keep sections that match
3588 @var{sectionpattern}.
3590 @item --remove-relocations=@var{sectionpattern}
3591 Remove relocations from the output file for any section matching
3592 @var{sectionpattern}. This option may be given more than once. Note
3593 that using this option inappropriately may make the output file
3594 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3598 --remove-relocations=.text.*
3601 will remove the relocations for all sections matching the patter
3604 If the first character of @var{sectionpattern} is the exclamation
3605 point (!) then matching sections will not have their relocation
3606 removed even if an earlier use of @option{--remove-relocations} on the
3607 same command line would otherwise cause the relocations to be removed.
3611 --remove-relocations=.text.* --remove-relocations=!.text.foo
3614 will remove all relocations for sections matching the pattern
3615 '.text.*', but will not remove relocations for the section
3618 @item --strip-section-headers
3619 Strip section headers. This option is specific to ELF files. Implies
3620 @option{--strip-all} and @option{--merge-notes}.
3629 @itemx --strip-debug
3630 Remove debugging symbols only.
3633 Remove the contents of all DWARF .dwo sections, leaving the
3634 remaining debugging sections and all symbols intact.
3635 See the description of this option in the @command{objcopy} section
3636 for more information.
3638 @item --strip-unneeded
3639 Remove all symbols that are not needed for relocation processing in
3640 addition to debugging symbols and sections stripped by
3641 @option{--strip-debug}.
3643 @item -K @var{symbolname}
3644 @itemx --keep-symbol=@var{symbolname}
3645 When stripping symbols, keep symbol @var{symbolname} even if it would
3646 normally be stripped. This option may be given more than once.
3649 @itemx --merge-notes
3650 @itemx --no-merge-notes
3651 For ELF files, attempt (or do not attempt) to reduce the size of any
3652 SHT_NOTE type sections by removing duplicate notes. The default is to
3653 attempt this reduction unless stripping debug or DWO information.
3655 @item -N @var{symbolname}
3656 @itemx --strip-symbol=@var{symbolname}
3657 Remove symbol @var{symbolname} from the source file. This option may be
3658 given more than once, and may be combined with strip options other than
3662 Put the stripped output in @var{file}, rather than replacing the
3663 existing file. When this argument is used, only one @var{objfile}
3664 argument may be specified.
3667 @itemx --preserve-dates
3668 Preserve the access and modification dates of the file.
3671 @itemx --enable-deterministic-archives
3672 @cindex deterministic archives
3673 @kindex --enable-deterministic-archives
3674 Operate in @emph{deterministic} mode. When copying archive members
3675 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3676 and use consistent file modes for all files.
3678 If @file{binutils} was configured with
3679 @option{--enable-deterministic-archives}, then this mode is on by default.
3680 It can be disabled with the @samp{-U} option, below.
3683 @itemx --disable-deterministic-archives
3684 @cindex deterministic archives
3685 @kindex --enable-deterministic-archives
3686 Do @emph{not} operate in @emph{deterministic} mode. This is the
3687 inverse of the @option{-D} option, above: when copying archive members
3688 and writing the archive index, use their actual UID, GID, timestamp,
3689 and file mode values.
3691 This is the default unless @file{binutils} was configured with
3692 @option{--enable-deterministic-archives}.
3696 Permit regular expressions in @var{symbolname}s used in other command
3697 line options. The question mark (?), asterisk (*), backslash (\) and
3698 square brackets ([]) operators can be used anywhere in the symbol
3699 name. If the first character of the symbol name is the exclamation
3700 point (!) then the sense of the switch is reversed for that symbol.
3707 would cause strip to only keep symbols that start with the letters
3708 ``fo'', but to discard the symbol ``foo''.
3711 @itemx --discard-all
3712 Remove non-global symbols.
3715 @itemx --discard-locals
3716 Remove compiler-generated local symbols.
3717 (These usually start with @samp{L} or @samp{.}.)
3719 @item --keep-section-symbols
3720 When stripping a file, perhaps with @option{--strip-debug} or
3721 @option{--strip-unneeded}, retain any symbols specifying section names,
3722 which would otherwise get stripped.
3724 @item --keep-file-symbols
3725 When stripping a file, perhaps with @option{--strip-debug} or
3726 @option{--strip-unneeded}, retain any symbols specifying source file names,
3727 which would otherwise get stripped.
3729 @item --only-keep-debug
3730 Strip a file, emptying the contents of any sections that would not be
3731 stripped by @option{--strip-debug} and leaving the debugging sections
3732 intact. In ELF files, this preserves all the note sections in the
3735 Note - the section headers of the stripped sections are preserved,
3736 including their sizes, but the contents of the section are discarded.
3737 The section headers are preserved so that other tools can match up the
3738 debuginfo file with the real executable, even if that executable has
3739 been relocated to a different address space.
3741 The intention is that this option will be used in conjunction with
3742 @option{--add-gnu-debuglink} to create a two part executable. One a
3743 stripped binary which will occupy less space in RAM and in a
3744 distribution and the second a debugging information file which is only
3745 needed if debugging abilities are required. The suggested procedure
3746 to create these files is as follows:
3749 @item Link the executable as normal. Assuming that it is called
3751 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3752 create a file containing the debugging info.
3753 @item Run @code{objcopy --strip-debug foo} to create a
3754 stripped executable.
3755 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3756 to add a link to the debugging info into the stripped executable.
3759 Note---the choice of @code{.dbg} as an extension for the debug info
3760 file is arbitrary. Also the @code{--only-keep-debug} step is
3761 optional. You could instead do this:
3764 @item Link the executable as normal.
3765 @item Copy @code{foo} to @code{foo.full}
3766 @item Run @code{strip --strip-debug foo}
3767 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3770 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3771 full executable. It does not have to be a file created by the
3772 @option{--only-keep-debug} switch.
3774 Note---this switch is only intended for use on fully linked files. It
3775 does not make sense to use it on object files where the debugging
3776 information may be incomplete. Besides the gnu_debuglink feature
3777 currently only supports the presence of one filename containing
3778 debugging information, not multiple filenames on a one-per-object-file
3783 Show the version number for @command{strip}.
3787 Verbose output: list all object files modified. In the case of
3788 archives, @samp{strip -v} lists all members of the archive.
3794 @c man begin SEEALSO strip
3795 the Info entries for @file{binutils}.
3799 @node c++filt, addr2line, strip, Top
3803 @cindex demangling C++ symbols
3805 @c man title cxxfilt demangle C++ and Java symbols
3808 @c man begin SYNOPSIS cxxfilt
3809 c++filt [@option{-_}|@option{--strip-underscore}]
3810 [@option{-n}|@option{--no-strip-underscore}]
3811 [@option{-p}|@option{--no-params}]
3812 [@option{-t}|@option{--types}]
3813 [@option{-i}|@option{--no-verbose}]
3814 [@option{-r}|@option{--no-recurse-limit}]
3815 [@option{-R}|@option{--recurse-limit}]
3816 [@option{-s} @var{format}|@option{--format=}@var{format}]
3817 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3821 @c man begin DESCRIPTION cxxfilt
3824 The C++ and Java languages provide function overloading, which means
3825 that you can write many functions with the same name, providing that
3826 each function takes parameters of different types. In order to be
3827 able to distinguish these similarly named functions C++ and Java
3828 encode them into a low-level assembler name which uniquely identifies
3829 each different version. This process is known as @dfn{mangling}. The
3831 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3832 MS-DOS this program is named @command{CXXFILT}.}
3833 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3834 names into user-level names so that they can be read.
3836 Every alphanumeric word (consisting of letters, digits, underscores,
3837 dollars, or periods) seen in the input is a potential mangled name.
3838 If the name decodes into a C++ name, the C++ name replaces the
3839 low-level name in the output, otherwise the original word is output.
3840 In this way you can pass an entire assembler source file, containing
3841 mangled names, through @command{c++filt} and see the same source file
3842 containing demangled names.
3844 You can also use @command{c++filt} to decipher individual symbols by
3845 passing them on the command line:
3848 c++filt @var{symbol}
3851 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3852 names from the standard input instead. All the results are printed on
3853 the standard output. The difference between reading names from the
3854 command line versus reading names from the standard input is that
3855 command-line arguments are expected to be just mangled names and no
3856 checking is performed to separate them from surrounding text. Thus
3863 will work and demangle the name to ``f()'' whereas:
3869 will not work. (Note the extra comma at the end of the mangled
3870 name which makes it invalid). This command however will work:
3873 echo _Z1fv, | c++filt -n
3876 and will display ``f(),'', i.e., the demangled name followed by a
3877 trailing comma. This behaviour is because when the names are read
3878 from the standard input it is expected that they might be part of an
3879 assembler source file where there might be extra, extraneous
3880 characters trailing after a mangled name. For example:
3883 .type _Z1fv, @@function
3888 @c man begin OPTIONS cxxfilt
3892 @itemx --strip-underscore
3893 On some systems, both the C and C++ compilers put an underscore in front
3894 of every name. For example, the C name @code{foo} gets the low-level
3895 name @code{_foo}. This option removes the initial underscore. Whether
3896 @command{c++filt} removes the underscore by default is target dependent.
3899 @itemx --no-strip-underscore
3900 Do not remove the initial underscore.
3904 When demangling the name of a function, do not display the types of
3905 the function's parameters.
3909 Attempt to demangle types as well as function names. This is disabled
3910 by default since mangled types are normally only used internally in
3911 the compiler, and they can be confused with non-mangled names. For example,
3912 a function called ``a'' treated as a mangled type name would be
3913 demangled to ``signed char''.
3917 Do not include implementation details (if any) in the demangled
3922 @itemx --recurse-limit
3923 @itemx --no-recurse-limit
3924 @itemx --recursion-limit
3925 @itemx --no-recursion-limit
3926 Enables or disables a limit on the amount of recursion performed
3927 whilst demangling strings. Since the name mangling formats allow for
3928 an infinite level of recursion it is possible to create strings whose
3929 decoding will exhaust the amount of stack space available on the host
3930 machine, triggering a memory fault. The limit tries to prevent this
3931 from happening by restricting recursion to 2048 levels of nesting.
3933 The default is for this limit to be enabled, but disabling it may be
3934 necessary in order to demangle truly complicated names. Note however
3935 that if the recursion limit is disabled then stack exhaustion is
3936 possible and any bug reports about such an event will be rejected.
3938 The @option{-r} option is a synonym for the
3939 @option{--no-recurse-limit} option. The @option{-R} option is a
3940 synonym for the @option{--recurse-limit} option.
3942 @item -s @var{format}
3943 @itemx --format=@var{format}
3944 @command{c++filt} can decode various methods of mangling, used by
3945 different compilers. The argument to this option selects which
3950 Automatic selection based on executable (the default method)
3952 the one used by the @sc{gnu} C++ compiler (g++)
3954 the one used by the Lucid compiler (lcc)
3956 the one specified by the C++ Annotated Reference Manual
3958 the one used by the HP compiler (aCC)
3960 the one used by the EDG compiler
3962 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3964 the one used by the @sc{gnu} Java compiler (gcj)
3966 the one used by the @sc{gnu} Ada compiler (GNAT).
3970 Print a summary of the options to @command{c++filt} and exit.
3973 Print the version number of @command{c++filt} and exit.
3979 @c man begin SEEALSO cxxfilt
3980 the Info entries for @file{binutils}.
3985 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3986 user interface are subject to change in future releases. In particular,
3987 a command-line option may be required in the future to decode a name
3988 passed as an argument on the command line; in other words,
3991 c++filt @var{symbol}
3995 may in a future release become
3998 c++filt @var{option} @var{symbol}
4006 @cindex address to file name and line number
4008 @c man title addr2line convert addresses or symbol+offset into file names and line numbers
4011 @c man begin SYNOPSIS addr2line
4012 addr2line [@option{-a}|@option{--addresses}]
4013 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
4014 [@option{-C}|@option{--demangle}[=@var{style}]]
4015 [@option{-r}|@option{--no-recurse-limit}]
4016 [@option{-R}|@option{--recurse-limit}]
4017 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
4018 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
4019 [@option{-i}|@option{--inlines}]
4020 [@option{-p}|@option{--pretty-print}]
4021 [@option{-j}|@option{--section=}@var{name}]
4022 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
4027 @c man begin DESCRIPTION addr2line
4029 @command{addr2line} translates addresses or symbol+offset into file names and line numbers.
4030 Given an address or symbol+offset in an executable or an offset in a section of a relocatable
4031 object, it uses the debugging information to figure out which file name and
4032 line number are associated with it.
4034 The executable or relocatable object to use is specified with the @option{-e}
4035 option. The default is the file @file{a.out}. The section in the relocatable
4036 object to use is specified with the @option{-j} option.
4038 @command{addr2line} has two modes of operation.
4040 In the first, hexadecimal addresses or symbol+offset are specified on the command line,
4041 and @command{addr2line} displays the file name and line number for each
4044 In the second, @command{addr2line} reads hexadecimal addresses or symbol+offset from
4045 standard input, and prints the file name and line number for each
4046 address on standard output. In this mode, @command{addr2line} may be used
4047 in a pipe to convert dynamically chosen addresses.
4049 The format of the output is @samp{FILENAME:LINENO}. By default
4050 each input address generates one line of output.
4052 Two options can generate additional lines before each
4053 @samp{FILENAME:LINENO} line (in that order).
4055 If the @option{-a} option is used then a line with the input address
4058 If the @option{-f} option is used, then a line with the
4059 @samp{FUNCTIONNAME} is displayed. This is the name of the function
4060 containing the address.
4062 One option can generate additional lines after the
4063 @samp{FILENAME:LINENO} line.
4065 If the @option{-i} option is used and the code at the given address is
4066 present there because of inlining by the compiler then additional
4067 lines are displayed afterwards. One or two extra lines (if the
4068 @option{-f} option is used) are displayed for each inlined function.
4070 Alternatively if the @option{-p} option is used then each input
4071 address generates a single, long, output line containing the address,
4072 the function name, the file name and the line number. If the
4073 @option{-i} option has also been used then any inlined functions will
4074 be displayed in the same manner, but on separate lines, and prefixed
4075 by the text @samp{(inlined by)}.
4077 If the file name or function name can not be determined,
4078 @command{addr2line} will print two question marks in their place. If the
4079 line number can not be determined, @command{addr2line} will print 0.
4081 When symbol+offset is used, +offset is optional, except when the symbol
4082 is ambigious with a hex number. The resolved symbols can be mangled
4083 or unmangled, except unmangled symbols with + are not allowed.
4087 @c man begin OPTIONS addr2line
4089 The long and short forms of options, shown here as alternatives, are
4095 Display the address before the function name, file and line number
4096 information. The address is printed with a @samp{0x} prefix to easily
4099 @item -b @var{bfdname}
4100 @itemx --target=@var{bfdname}
4101 @cindex object code format
4102 Specify that the object-code format for the object files is
4106 @itemx --demangle[=@var{style}]
4107 @cindex demangling in objdump
4108 Decode (@dfn{demangle}) low-level symbol names into user-level names.
4109 Besides removing any initial underscore prepended by the system, this
4110 makes C++ function names readable. Different compilers have different
4111 mangling styles. The optional demangling style argument can be used to
4112 choose an appropriate demangling style for your compiler. @xref{c++filt},
4113 for more information on demangling.
4115 @item -e @var{filename}
4116 @itemx --exe=@var{filename}
4117 Specify the name of the executable for which addresses should be
4118 translated. The default file is @file{a.out}.
4122 Display function names as well as file and line number information.
4126 Display only the base of each file name.
4130 If the address belongs to a function that was inlined, the source
4131 information for all enclosing scopes back to the first non-inlined
4132 function will also be printed. For example, if @code{main} inlines
4133 @code{callee1} which inlines @code{callee2}, and address is from
4134 @code{callee2}, the source information for @code{callee1} and @code{main}
4135 will also be printed.
4139 Read offsets relative to the specified section instead of absolute addresses.
4142 @itemx --pretty-print
4143 Make the output more human friendly: each location are printed on one line.
4144 If option @option{-i} is specified, lines for all enclosing scopes are
4145 prefixed with @samp{(inlined by)}.
4149 @itemx --recurse-limit
4150 @itemx --no-recurse-limit
4151 @itemx --recursion-limit
4152 @itemx --no-recursion-limit
4153 Enables or disables a limit on the amount of recursion performed
4154 whilst demangling strings. Since the name mangling formats allow for
4155 an infinite level of recursion it is possible to create strings whose
4156 decoding will exhaust the amount of stack space available on the host
4157 machine, triggering a memory fault. The limit tries to prevent this
4158 from happening by restricting recursion to 2048 levels of nesting.
4160 The default is for this limit to be enabled, but disabling it may be
4161 necessary in order to demangle truly complicated names. Note however
4162 that if the recursion limit is disabled then stack exhaustion is
4163 possible and any bug reports about such an event will be rejected.
4165 The @option{-r} option is a synonym for the
4166 @option{--no-recurse-limit} option. The @option{-R} option is a
4167 synonym for the @option{--recurse-limit} option.
4169 Note this option is only effective if the @option{-C} or
4170 @option{--demangle} option has been enabled.
4177 @c man begin SEEALSO addr2line
4178 Info entries for @file{binutils}.
4185 @command{windmc} may be used to generator Windows message resources.
4188 @emph{Warning:} @command{windmc} is not always built as part of the binary
4189 utilities, since it is only useful for Windows targets.
4192 @c man title windmc generates Windows message resources
4195 @c man begin SYNOPSIS windmc
4196 windmc [options] input-file
4200 @c man begin DESCRIPTION windmc
4202 @command{windmc} reads message definitions from an input file (.mc) and
4203 translate them into a set of output files. The output files may be of
4208 A C header file containing the message definitions.
4211 A resource file compilable by the @command{windres} tool.
4214 One or more binary files containing the resource data for a specific
4218 A C include file that maps message id's to their symbolic name.
4221 The exact description of these different formats is available in
4222 documentation from Microsoft.
4224 When @command{windmc} converts from the @code{mc} format to the @code{bin}
4225 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
4226 Windows Message Compiler.
4230 @c man begin OPTIONS windmc
4235 Specifies that the input file specified is ASCII. This is the default
4240 Specifies that messages in the output @code{bin} files should be in ASCII
4245 Specifies that @code{bin} filenames should have to be prefixed by the
4246 basename of the source file.
4250 Sets the customer bit in all message id's.
4252 @item -C @var{codepage}
4253 @itemx --codepage_in @var{codepage}
4254 Sets the default codepage to be used to convert input file to UTF16. The
4255 default is ocdepage 1252.
4258 @itemx --decimal_values
4259 Outputs the constants in the header file in decimal. Default is using
4263 @itemx --extension @var{ext}
4264 The extension for the header file. The default is .h extension.
4266 @item -F @var{target}
4267 @itemx --target @var{target}
4268 Specify the BFD format to use for a bin file as output. This
4269 is a BFD target name; you can use the @option{--help} option to see a list
4270 of supported targets. Normally @command{windmc} will use the default
4271 format, which is the first one listed by the @option{--help} option.
4273 @ref{Target Selection}.
4277 @itemx --headerdir @var{path}
4278 The target directory of the generated header file. The default is the
4283 Displays a list of command-line options and then exits.
4285 @item -m @var{characters}
4286 @itemx --maxlength @var{characters}
4287 Instructs @command{windmc} to generate a warning if the length
4288 of any message exceeds the number specified.
4291 @itemx --nullterminate
4292 Terminate message text in @code{bin} files by zero. By default they are
4293 terminated by CR/LF.
4296 @itemx --hresult_use
4297 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
4298 file, using HRESULT definitions. Status codes are used if the flag is not
4301 @item -O @var{codepage}
4302 @itemx --codepage_out @var{codepage}
4303 Sets the default codepage to be used to output text files. The default
4307 @itemx --rcdir @var{path}
4308 The target directory for the generated @code{rc} script and the generated
4309 @code{bin} files that the resource compiler script includes. The default
4310 is the current directory.
4314 Specifies that the input file is UTF16.
4317 @itemx --unicode_out
4318 Specifies that messages in the output @code{bin} file should be in UTF16
4319 format. This is the default behaviour.
4323 Enable verbose mode.
4327 Prints the version number for @command{windmc}.
4330 @itemx --xdgb @var{path}
4331 The path of the @code{dbg} C include file that maps message id's to the
4332 symbolic name. No such file is generated without specifying the switch.
4338 @c man begin SEEALSO windmc
4339 the Info entries for @file{binutils}.
4346 @command{windres} may be used to manipulate Windows resources.
4349 @emph{Warning:} @command{windres} is not always built as part of the binary
4350 utilities, since it is only useful for Windows targets.
4353 @c man title windres manipulate Windows resources
4356 @c man begin SYNOPSIS windres
4357 windres [options] [input-file] [output-file]
4361 @c man begin DESCRIPTION windres
4363 @command{windres} reads resources from an input file and copies them into
4364 an output file. Either file may be in one of three formats:
4368 A text format read by the Resource Compiler.
4371 A binary format generated by the Resource Compiler.
4374 A COFF object or executable.
4377 The exact description of these different formats is available in
4378 documentation from Microsoft.
4380 When @command{windres} converts from the @code{rc} format to the @code{res}
4381 format, it is acting like the Windows Resource Compiler. When
4382 @command{windres} converts from the @code{res} format to the @code{coff}
4383 format, it is acting like the Windows @code{CVTRES} program.
4385 When @command{windres} generates an @code{rc} file, the output is similar
4386 but not identical to the format expected for the input. When an input
4387 @code{rc} file refers to an external filename, an output @code{rc} file
4388 will instead include the file contents.
4390 If the input or output format is not specified, @command{windres} will
4391 guess based on the file name, or, for the input file, the file contents.
4392 A file with an extension of @file{.rc} will be treated as an @code{rc}
4393 file, a file with an extension of @file{.res} will be treated as a
4394 @code{res} file, and a file with an extension of @file{.o} or
4395 @file{.exe} will be treated as a @code{coff} file.
4397 If no output file is specified, @command{windres} will print the resources
4398 in @code{rc} format to standard output.
4400 The normal use is for you to write an @code{rc} file, use @command{windres}
4401 to convert it to a COFF object file, and then link the COFF file into
4402 your application. This will make the resources described in the
4403 @code{rc} file available to Windows.
4407 @c man begin OPTIONS windres
4410 @item -i @var{filename}
4411 @itemx --input @var{filename}
4412 The name of the input file. If this option is not used, then
4413 @command{windres} will use the first non-option argument as the input file
4414 name. If there are no non-option arguments, then @command{windres} will
4415 read from standard input. @command{windres} can not read a COFF file from
4418 @item -o @var{filename}
4419 @itemx --output @var{filename}
4420 The name of the output file. If this option is not used, then
4421 @command{windres} will use the first non-option argument, after any used
4422 for the input file name, as the output file name. If there is no
4423 non-option argument, then @command{windres} will write to standard output.
4424 @command{windres} can not write a COFF file to standard output. Note,
4425 for compatibility with @command{rc} the option @option{-fo} is also
4426 accepted, but its use is not recommended.
4428 @item -J @var{format}
4429 @itemx --input-format @var{format}
4430 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4431 @samp{coff}. If no input format is specified, @command{windres} will
4432 guess, as described above.
4434 @item -O @var{format}
4435 @itemx --output-format @var{format}
4436 The output format to generate. @var{format} may be @samp{res},
4437 @samp{rc}, or @samp{coff}. If no output format is specified,
4438 @command{windres} will guess, as described above.
4440 @item -F @var{target}
4441 @itemx --target @var{target}
4442 Specify the BFD format to use for a COFF file as input or output. This
4443 is a BFD target name; you can use the @option{--help} option to see a list
4444 of supported targets. Normally @command{windres} will use the default
4445 format, which is the first one listed by the @option{--help} option.
4447 @ref{Target Selection}.
4450 @item --preprocessor @var{program}
4451 When @command{windres} reads an @code{rc} file, it runs it through the C
4452 preprocessor first. This option may be used to specify the preprocessor
4453 to use. The default preprocessor is @code{gcc}.
4455 @item --preprocessor-arg @var{option}
4456 When @command{windres} reads an @code{rc} file, it runs it through
4457 the C preprocessor first. This option may be used to specify additional
4458 text to be passed to preprocessor on its command line.
4459 This option can be used multiple times to add multiple options to the
4460 preprocessor command line.
4461 If the @option{--preprocessor} option has not been specified then a
4462 default set of preprocessor arguments will be used, with any
4463 @option{--preprocessor-arg} options being placed after them on the
4464 command line. These default arguments are @code{-E},
4465 @code{-xc-header} and @code{-DRC_INVOKED}.
4467 @item -I @var{directory}
4468 @itemx --include-dir @var{directory}
4469 Specify an include directory to use when reading an @code{rc} file.
4470 @command{windres} will pass this to the preprocessor as an @option{-I}
4471 option. @command{windres} will also search this directory when looking for
4472 files named in the @code{rc} file. If the argument passed to this command
4473 matches any of the supported @var{formats} (as described in the @option{-J}
4474 option), it will issue a deprecation warning, and behave just like the
4475 @option{-J} option. New programs should not use this behaviour. If a
4476 directory happens to match a @var{format}, simple prefix it with @samp{./}
4477 to disable the backward compatibility.
4479 @item -D @var{target}
4480 @itemx --define @var{sym}[=@var{val}]
4481 Specify a @option{-D} option to pass to the preprocessor when reading an
4484 @item -U @var{target}
4485 @itemx --undefine @var{sym}
4486 Specify a @option{-U} option to pass to the preprocessor when reading an
4490 Ignored for compatibility with rc.
4493 Enable verbose mode. This tells you what the preprocessor is if you
4497 @item --codepage @var{val}
4498 Specify the default codepage to use when reading an @code{rc} file.
4499 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4500 codepage code. The valid range is from zero up to 0xffff, but the
4501 validity of the codepage is host and configuration dependent.
4504 @item --language @var{val}
4505 Specify the default language to use when reading an @code{rc} file.
4506 @var{val} should be a hexadecimal language code. The low eight bits are
4507 the language, and the high eight bits are the sublanguage.
4509 @item --use-temp-file
4510 Use a temporary file to instead of using popen to read the output of
4511 the preprocessor. Use this option if the popen implementation is buggy
4512 on the host (eg., certain non-English language versions of Windows 95 and
4513 Windows 98 are known to have buggy popen where the output will instead
4516 @item --no-use-temp-file
4517 Use popen, not a temporary file, to read the output of the preprocessor.
4518 This is the default behaviour.
4522 Prints a usage summary.
4526 Prints the version number for @command{windres}.
4529 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4530 this will turn on parser debugging.
4536 @c man begin SEEALSO windres
4537 the Info entries for @file{binutils}.
4546 @command{dlltool} is used to create the files needed to create dynamic
4547 link libraries (DLLs) on systems which understand PE format image
4548 files such as Windows. A DLL contains an export table which contains
4549 information that the runtime loader needs to resolve references from a
4550 referencing program.
4552 The export table is generated by this program by reading in a
4553 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4554 will be in the DLL. A @file{.o} file can contain information in
4555 special @samp{.drectve} sections with export information.
4558 @emph{Note:} @command{dlltool} is not always built as part of the
4559 binary utilities, since it is only useful for those targets which
4563 @c man title dlltool create files needed to build and use DLLs
4566 @c man begin SYNOPSIS dlltool
4567 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4568 [@option{-b}|@option{--base-file} @var{base-file-name}]
4569 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4570 [@option{-z}|@option{--output-def} @var{def-file-name}]
4571 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4572 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4573 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4574 [@option{--exclude-symbols} @var{list}]
4575 [@option{--no-default-excludes}]
4576 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4577 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4578 [@option{-a}|@option{--add-indirect}]
4579 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4580 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4581 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4582 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4583 [@option{--use-nul-prefixed-import-tables}]
4584 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4585 [@option{-i}|@option{--interwork}]
4586 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4587 [@option{-v}|@option{--verbose}]
4588 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4589 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4590 [@option{--deterministic-libraries}] [@option{--non-deterministic-libraries}]
4591 [object-file @dots{}]
4595 @c man begin DESCRIPTION dlltool
4597 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4598 @option{-b} options as well as object files specified on the command
4599 line. It then processes these inputs and if the @option{-e} option has
4600 been specified it creates a exports file. If the @option{-l} option
4601 has been specified it creates a library file and if the @option{-z} option
4602 has been specified it creates a def file. Any or all of the @option{-e},
4603 @option{-l} and @option{-z} options can be present in one invocation of
4606 When creating a DLL, along with the source for the DLL, it is necessary
4607 to have three other files. @command{dlltool} can help with the creation of
4610 The first file is a @file{.def} file which specifies which functions are
4611 exported from the DLL, which functions the DLL imports, and so on. This
4612 is a text file and can be created by hand, or @command{dlltool} can be used
4613 to create it using the @option{-z} option. In this case @command{dlltool}
4614 will scan the object files specified on its command line looking for
4615 those functions which have been specially marked as being exported and
4616 put entries for them in the @file{.def} file it creates.
4618 In order to mark a function as being exported from a DLL, it needs to
4619 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4620 section of the object file. This can be done in C by using the
4624 asm (".section .drectve");
4625 asm (".ascii \"-export:my_func\"");
4627 int my_func (void) @{ @dots{} @}
4630 The second file needed for DLL creation is an exports file. This file
4631 is linked with the object files that make up the body of the DLL and it
4632 handles the interface between the DLL and the outside world. This is a
4633 binary file and it can be created by giving the @option{-e} option to
4634 @command{dlltool} when it is creating or reading in a @file{.def} file.
4636 The third file needed for DLL creation is the library file that programs
4637 will link with in order to access the functions in the DLL (an `import
4638 library'). This file can be created by giving the @option{-l} option to
4639 dlltool when it is creating or reading in a @file{.def} file.
4641 If the @option{-y} option is specified, dlltool generates a delay-import
4642 library that can be used instead of the normal import library to allow
4643 a program to link to the dll only as soon as an imported function is
4644 called for the first time. The resulting executable will need to be
4645 linked to the static delayimp library containing __delayLoadHelper2(),
4646 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4648 @command{dlltool} builds the library file by hand, but it builds the
4649 exports file by creating temporary files containing assembler statements
4650 and then assembling these. The @option{-S} command-line option can be
4651 used to specify the path to the assembler that dlltool will use,
4652 and the @option{-f} option can be used to pass specific flags to that
4653 assembler. The @option{-n} can be used to prevent dlltool from deleting
4654 these temporary assembler files when it is done, and if @option{-n} is
4655 specified twice then this will prevent dlltool from deleting the
4656 temporary object files it used to build the library.
4658 Here is an example of creating a DLL from a source file @samp{dll.c} and
4659 also creating a program (from an object file called @samp{program.o})
4664 dlltool -e exports.o -l dll.lib dll.o
4665 gcc dll.o exports.o -o dll.dll
4666 gcc program.o dll.lib -o program
4670 @command{dlltool} may also be used to query an existing import library
4671 to determine the name of the DLL to which it is associated. See the
4672 description of the @option{-I} or @option{--identify} option.
4676 @c man begin OPTIONS dlltool
4678 The command-line options have the following meanings:
4682 @item -d @var{filename}
4683 @itemx --input-def @var{filename}
4684 @cindex input .def file
4685 Specifies the name of a @file{.def} file to be read in and processed.
4687 @item -b @var{filename}
4688 @itemx --base-file @var{filename}
4690 Specifies the name of a base file to be read in and processed. The
4691 contents of this file will be added to the relocation section in the
4692 exports file generated by dlltool.
4694 @item -e @var{filename}
4695 @itemx --output-exp @var{filename}
4696 Specifies the name of the export file to be created by dlltool.
4698 @item -z @var{filename}
4699 @itemx --output-def @var{filename}
4700 Specifies the name of the @file{.def} file to be created by dlltool.
4702 @item -l @var{filename}
4703 @itemx --output-lib @var{filename}
4704 Specifies the name of the library file to be created by dlltool.
4706 @item -y @var{filename}
4707 @itemx --output-delaylib @var{filename}
4708 Specifies the name of the delay-import library file to be created by dlltool.
4710 @item --deterministic-libraries
4711 @itemx --non-deterministic-libraries
4712 When creating output libraries in response to either the
4713 @option{--output-lib} or @option{--output-delaylib} options either use
4714 the value of zero for any timestamps, user ids and group ids created
4715 (@option{--deterministic-libraries}) or the actual timestamps, user
4716 ids and group ids (@option{--non-deterministic-libraries}).
4718 @item --export-all-symbols
4719 Treat all global and weak defined symbols found in the input object
4720 files as symbols to be exported. There is a small list of symbols which
4721 are not exported by default; see the @option{--no-default-excludes}
4722 option. You may add to the list of symbols to not export by using the
4723 @option{--exclude-symbols} option.
4725 @item --no-export-all-symbols
4726 Only export symbols explicitly listed in an input @file{.def} file or in
4727 @samp{.drectve} sections in the input object files. This is the default
4728 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4729 attributes in the source code.
4731 @item --exclude-symbols @var{list}
4732 Do not export the symbols in @var{list}. This is a list of symbol names
4733 separated by comma or colon characters. The symbol names should not
4734 contain a leading underscore. This is only meaningful when
4735 @option{--export-all-symbols} is used.
4737 @item --no-default-excludes
4738 When @option{--export-all-symbols} is used, it will by default avoid
4739 exporting certain special symbols. The current list of symbols to avoid
4740 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4741 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4742 to go ahead and export these special symbols. This is only meaningful
4743 when @option{--export-all-symbols} is used.
4746 @itemx --as @var{path}
4747 Specifies the path, including the filename, of the assembler to be used
4748 to create the exports file.
4750 @item -f @var{options}
4751 @itemx --as-flags @var{options}
4752 Specifies any specific command-line options to be passed to the
4753 assembler when building the exports file. This option will work even if
4754 the @option{-S} option is not used. This option only takes one argument,
4755 and if it occurs more than once on the command line, then later
4756 occurrences will override earlier occurrences. So if it is necessary to
4757 pass multiple options to the assembler they should be enclosed in
4761 @itemx --dll-name @var{name}
4762 Specifies the name to be stored in the @file{.def} file as the name of
4763 the DLL when the @option{-e} option is used. If this option is not
4764 present, then the filename given to the @option{-e} option will be
4765 used as the name of the DLL.
4767 @item -m @var{machine}
4768 @itemx -machine @var{machine}
4769 Specifies the type of machine for which the library file should be
4770 built. @command{dlltool} has a built in default type, depending upon how
4771 it was created, but this option can be used to override that. This is
4772 normally only useful when creating DLLs for an ARM processor, when the
4773 contents of the DLL are actually encode using Thumb instructions.
4776 @itemx --add-indirect
4777 Specifies that when @command{dlltool} is creating the exports file it
4778 should add a section which allows the exported functions to be
4779 referenced without using the import library. Whatever the hell that
4783 @itemx --add-underscore
4784 Specifies that when @command{dlltool} is creating the exports file it
4785 should prepend an underscore to the names of @emph{all} exported symbols.
4787 @item --no-leading-underscore
4788 @item --leading-underscore
4789 Specifies whether standard symbol should be forced to be prefixed, or
4792 @item --add-stdcall-underscore
4793 Specifies that when @command{dlltool} is creating the exports file it
4794 should prepend an underscore to the names of exported @emph{stdcall}
4795 functions. Variable names and non-stdcall function names are not modified.
4796 This option is useful when creating GNU-compatible import libs for third
4797 party DLLs that were built with MS-Windows tools.
4801 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4802 of stdcall functions that will be imported from the DLL. This is
4803 useful when creating an import library for a DLL which exports stdcall
4804 functions but without the usual @samp{@@<number>} symbol name suffix.
4806 This does not change the naming of symbols provided by the import library
4807 to programs linked against it, but only the entries in the import table
4808 (ie the .idata section).
4811 @itemx --add-stdcall-alias
4812 Specifies that when @command{dlltool} is creating the exports file it
4813 should add aliases for stdcall symbols without @samp{@@ <number>}
4814 in addition to the symbols with @samp{@@ <number>}.
4817 @itemx --ext-prefix-alias @var{prefix}
4818 Causes @command{dlltool} to create external aliases for all DLL
4819 imports with the specified prefix. The aliases are created for both
4820 external and import symbols with no leading underscore.
4824 Specifies that when @command{dlltool} is creating the exports and library
4825 files it should omit the @code{.idata4} section. This is for compatibility
4826 with certain operating systems.
4828 @item --use-nul-prefixed-import-tables
4829 Specifies that when @command{dlltool} is creating the exports and library
4830 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4831 element. This emulates old gnu import library generation of
4832 @code{dlltool}. By default this option is turned off.
4836 Specifies that when @command{dlltool} is creating the exports and library
4837 files it should omit the @code{.idata5} section. This is for compatibility
4838 with certain operating systems.
4840 @item -I @var{filename}
4841 @itemx --identify @var{filename}
4842 Specifies that @command{dlltool} should inspect the import library
4843 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4844 of the associated DLL(s). This can be performed in addition to any
4845 other operations indicated by the other options and arguments.
4846 @command{dlltool} fails if the import library does not exist or is not
4847 actually an import library. See also @option{--identify-strict}.
4849 @item --identify-strict
4850 Modifies the behavior of the @option{--identify} option, such
4851 that an error is reported if @var{filename} is associated with
4856 Specifies that @command{dlltool} should mark the objects in the library
4857 file and exports file that it produces as supporting interworking
4858 between ARM and Thumb code.
4862 Makes @command{dlltool} preserve the temporary assembler files it used to
4863 create the exports file. If this option is repeated then dlltool will
4864 also preserve the temporary object files it uses to create the library
4867 @item -t @var{prefix}
4868 @itemx --temp-prefix @var{prefix}
4869 Makes @command{dlltool} use @var{prefix} when constructing the names of
4870 temporary assembler and object files. By default, the temp file prefix
4871 is generated from the pid.
4875 Make dlltool describe what it is doing.
4879 Displays a list of command-line options and then exits.
4883 Displays dlltool's version number and then exits.
4890 * def file format:: The format of the dlltool @file{.def} file
4893 @node def file format
4894 @section The format of the @command{dlltool} @file{.def} file
4896 A @file{.def} file contains any number of the following commands:
4900 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4901 The result is going to be named @var{name}@code{.exe}.
4903 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4904 The result is going to be named @var{name}@code{.dll}.
4905 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4906 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4909 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4910 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4911 Declares @var{name1} as an exported symbol from the DLL, with optional
4912 ordinal number @var{integer}, or declares @var{name1} as an alias
4913 (forward) of the function @var{external-name} in the DLL.
4914 If @var{its_name} is specified, this name is used as string in export table.
4916 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4917 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4918 If you want to use LIBRARY as name then you need to quote it.
4920 @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{]} *}
4921 Declares that @var{external-name} or the exported function whose
4922 ordinal number is @var{integer} is to be imported from the file
4923 @var{module-name}. If @var{internal-name} is specified then this is
4924 the name that the imported function will be referred to in the body of
4926 If @var{its_name} is specified, this name is used as string in import table.
4927 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4928 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4929 If you want to use LIBRARY as name then you need to quote it.
4931 @item @code{DESCRIPTION} @var{string}
4932 Puts @var{string} into the output @file{.exp} file in the
4933 @code{.rdata} section.
4935 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4936 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4937 Generates @code{--stack} or @code{--heap}
4938 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4939 section. The linker will see this and act upon it.
4941 @item @code{CODE} @var{attr} @code{+}
4942 @item @code{DATA} @var{attr} @code{+}
4943 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4944 Generates @code{--attr} @var{section-name} @var{attr} in the output
4945 @code{.drectve} section, where @var{attr} is one of @code{READ},
4946 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4947 this and act upon it.
4952 @c man begin SEEALSO dlltool
4953 The Info pages for @file{binutils}.
4960 @cindex ELF file information
4963 @c man title readelf display information about ELF files
4966 @c man begin SYNOPSIS readelf
4967 readelf [@option{-a}|@option{--all}]
4968 [@option{-h}|@option{--file-header}]
4969 [@option{-l}|@option{--program-headers}|@option{--segments}]
4970 [@option{-S}|@option{--section-headers}|@option{--sections}]
4971 [@option{-g}|@option{--section-groups}]
4972 [@option{-t}|@option{--section-details}]
4973 [@option{-e}|@option{--headers}]
4974 [@option{-s}|@option{--syms}|@option{--symbols}]
4975 [@option{--dyn-syms}|@option{--lto-syms}]
4976 [@option{--sym-base=[0|8|10|16]}]
4977 [@option{--demangle@var{=style}}|@option{--no-demangle}]
4979 [@option{--recurse-limit}|@option{--no-recurse-limit}]
4980 [@option{-U} @var{method}|@option{--unicode=}@var{method}]
4981 [@option{-X}|@option{--extra-sym-info}|@option{--no-extra-sym-info}]
4982 [@option{-n}|@option{--notes}]
4983 [@option{-r}|@option{--relocs}]
4984 [@option{-u}|@option{--unwind}]
4985 [@option{-d}|@option{--dynamic}]
4986 [@option{-V}|@option{--version-info}]
4987 [@option{-A}|@option{--arch-specific}]
4988 [@option{-D}|@option{--use-dynamic}]
4989 [@option{-L}|@option{--lint}|@option{--enable-checks}]
4990 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4991 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4992 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4993 [@option{-z}|@option{--decompress}]
4994 [@option{-c}|@option{--archive-index}]
4995 [@option{-w[lLiaprmfFsoORtUuTgAck]}|
4996 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
4997 [@option{-wK}|@option{--debug-dump=follow-links}]
4998 [@option{-wN}|@option{--debug-dump=no-follow-links}]
4999 [@option{-wD}|@option{--debug-dump=use-debuginfod}]
5000 [@option{-wE}|@option{--debug-dump=do-not-use-debuginfod}]
5001 [@option{-P}|@option{--process-links}]
5002 [@option{--dwarf-depth=@var{n}}]
5003 [@option{--dwarf-start=@var{n}}]
5004 [@option{--ctf=}@var{section}]
5005 [@option{--ctf-parent=}@var{section}]
5006 [@option{--ctf-symbols=}@var{section}]
5007 [@option{--ctf-strings=}@var{section}]
5008 [@option{--sframe=}@var{section}]
5009 [@option{-I}|@option{--histogram}]
5010 [@option{-v}|@option{--version}]
5011 [@option{-W}|@option{--wide}]
5012 [@option{-T}|@option{--silent-truncation}]
5013 [@option{-H}|@option{--help}]
5014 @var{elffile}@dots{}
5018 @c man begin DESCRIPTION readelf
5020 @command{readelf} displays information about one or more ELF format object
5021 files. The options control what particular information to display.
5023 @var{elffile}@dots{} are the object files to be examined. 32-bit and
5024 64-bit ELF files are supported, as are archives containing ELF files.
5026 This program performs a similar function to @command{objdump} but it
5027 goes into more detail and it exists independently of the @sc{bfd}
5028 library, so if there is a bug in @sc{bfd} then readelf will not be
5033 @c man begin OPTIONS readelf
5035 The long and short forms of options, shown here as alternatives, are
5036 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
5042 Equivalent to specifying @option{--file-header},
5043 @option{--program-headers}, @option{--sections}, @option{--symbols},
5044 @option{--relocs}, @option{--dynamic}, @option{--notes},
5045 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
5046 @option{--section-groups} and @option{--histogram}.
5048 Note - this option does not enable @option{--use-dynamic} itself, so
5049 if that option is not present on the command line then dynamic symbols
5050 and dynamic relocs will not be displayed.
5053 @itemx --file-header
5054 @cindex ELF file header information
5055 Displays the information contained in the ELF header at the start of the
5059 @itemx --program-headers
5061 @cindex ELF program header information
5062 @cindex ELF segment information
5063 Displays the information contained in the file's segment headers, if it
5068 Suppress "no symbols" diagnostic.
5072 @itemx --section-headers
5073 @cindex ELF section information
5074 Displays the information contained in the file's section headers, if it
5078 @itemx --section-groups
5079 @cindex ELF section group information
5080 Displays the information contained in the file's section groups, if it
5084 @itemx --section-details
5085 @cindex ELF section information
5086 Displays the detailed section information. Implies @option{-S}.
5091 @cindex ELF symbol table information
5092 Displays the entries in symbol table section of the file, if it has one.
5093 If a symbol has version information associated with it then this is
5094 displayed as well. The version string is displayed as a suffix to the
5095 symbol name, preceded by an @@ character. For example
5096 @samp{foo@@VER_1}. If the version is the default version to be used
5097 when resolving unversioned references to the symbol then it is
5098 displayed as a suffix preceded by two @@ characters. For example
5099 @samp{foo@@@@VER_2}.
5102 @cindex ELF dynamic symbol table information
5103 Displays the entries in dynamic symbol table section of the file, if it
5104 has one. The output format is the same as the format used by the
5105 @option{--syms} option.
5108 @cindex LTO symbol table
5109 Displays the contents of any LTO symbol tables in the file.
5111 @item --sym-base=[0|8|10|16]
5112 @cindex symbol table size base
5113 Forces the size field of the symbol table to use the given base. Any
5114 unrecognized options will be treated as @samp{0}. @option{--sym-base=0}
5115 represents the default and legacy behaviour. This will output sizes as decimal
5116 for numbers less than 100000. For sizes 100000 and greater hexadecimal notation
5117 will be used with a 0x prefix.
5118 @option{--sym-base=8} will give the symbol sizes in octal.
5119 @option{--sym-base=10} will always give the symbol sizes in decimal.
5120 @option{--sym-base=16} will always give the symbol sizes in hexadecimal with a
5124 @itemx --demangle[=@var{style}]
5125 @cindex demangling in nm
5126 Decode (@dfn{demangle}) low-level symbol names into user-level names.
5127 This makes C++ function names readable. Different compilers have
5128 different mangling styles. The optional demangling style argument can
5129 be used to choose an appropriate demangling style for your
5130 compiler. @xref{c++filt}, for more information on demangling.
5133 Do not demangle low-level symbol names. This is the default.
5135 @item --recurse-limit
5136 @itemx --no-recurse-limit
5137 @itemx --recursion-limit
5138 @itemx --no-recursion-limit
5139 Enables or disables a limit on the amount of recursion performed
5140 whilst demangling strings. Since the name mangling formats allow for
5141 an infinite level of recursion it is possible to create strings whose
5142 decoding will exhaust the amount of stack space available on the host
5143 machine, triggering a memory fault. The limit tries to prevent this
5144 from happening by restricting recursion to 2048 levels of nesting.
5146 The default is for this limit to be enabled, but disabling it may be
5147 necessary in order to demangle truly complicated names. Note however
5148 that if the recursion limit is disabled then stack exhaustion is
5149 possible and any bug reports about such an event will be rejected.
5151 @item -U @var{[d|i|l|e|x|h]}
5152 @itemx --unicode=[default|invalid|locale|escape|hex|highlight]
5153 Controls the display of non-ASCII characters in identifier names.
5154 The default (@option{--unicode=locale} or @option{--unicode=default}) is
5155 to treat them as multibyte characters and display them in the current
5156 locale. All other versions of this option treat the bytes as UTF-8
5157 encoded values and attempt to interpret them. If they cannot be
5158 interpreted or if the @option{--unicode=invalid} option is used then
5159 they are displayed as a sequence of hex bytes, encloses in curly
5160 parethesis characters.
5162 Using the @option{--unicode=escape} option will display the characters
5163 as as unicode escape sequences (@var{\uxxxx}). Using the
5164 @option{--unicode=hex} will display the characters as hex byte
5165 sequences enclosed between angle brackets.
5167 Using the @option{--unicode=highlight} will display the characters as
5168 unicode escape sequences but it will also highlighted them in red,
5169 assuming that colouring is supported by the output device. The
5170 colouring is intended to draw attention to the presence of unicode
5171 sequences when they might not be expected.
5174 @itemx --extra-sym-info
5175 When displaying details of symbols, include extra information not
5176 normally presented. Currently this just adds the name of the section
5177 referenced by the symbol's index field, if there is one. In the
5178 future more information may be displayed when this option is enabled.
5180 Enabling this option effectively enables the @option{--wide} option as
5181 well, at least when displaying symbol information.
5183 @item --no-extra-sym-info
5184 Disables the effect of the @option{--extra-sym-info} option. This
5189 Display all the headers in the file. Equivalent to @option{-h -l -S}.
5194 Displays the contents of the NOTE segments and/or sections, if any.
5198 @cindex ELF reloc information
5199 Displays the contents of the file's relocation section, if it has one.
5203 @cindex unwind information
5204 Displays the contents of the file's unwind section, if it has one. Only
5205 the unwind sections for IA64 ELF files, as well as ARM unwind tables
5206 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
5207 support is not yet implemented for your architecture you could try
5208 dumping the contents of the @var{.eh_frames} section using the
5209 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
5214 @cindex ELF dynamic section information
5215 Displays the contents of the file's dynamic section, if it has one.
5218 @itemx --version-info
5219 @cindex ELF version sections information
5220 Displays the contents of the version sections in the file, it they
5224 @itemx --arch-specific
5225 Displays architecture-specific information in the file, if there
5229 @itemx --use-dynamic
5230 When displaying symbols, this option makes @command{readelf} use the
5231 symbol hash tables in the file's dynamic section, rather than the
5232 symbol table sections.
5234 When displaying relocations, this option makes @command{readelf}
5235 display the dynamic relocations rather than the static relocations.
5239 @itemx --enable-checks
5240 Displays warning messages about possible problems with the file(s)
5241 being examined. If used on its own then all of the contents of the
5242 file(s) will be examined. If used with one of the dumping options
5243 then the warning messages will only be produced for the things being
5246 @item -x <number or name>
5247 @itemx --hex-dump=<number or name>
5248 Displays the contents of the indicated section as a hexadecimal bytes.
5249 A number identifies a particular section by index in the section table;
5250 any other string identifies all sections with that name in the object file.
5252 @item -R <number or name>
5253 @itemx --relocated-dump=<number or name>
5254 Displays the contents of the indicated section as a hexadecimal
5255 bytes. A number identifies a particular section by index in the
5256 section table; any other string identifies all sections with that name
5257 in the object file. The contents of the section will be relocated
5258 before they are displayed.
5260 @item -p <number or name>
5261 @itemx --string-dump=<number or name>
5262 Displays the contents of the indicated section as printable strings.
5263 A number identifies a particular section by index in the section table;
5264 any other string identifies all sections with that name in the object file.
5268 Requests that the section(s) being dumped by @option{x}, @option{R} or
5269 @option{p} options are decompressed before being displayed. If the
5270 section(s) are not compressed then they are displayed as is.
5273 @itemx --archive-index
5274 @cindex Archive file symbol index information
5275 Displays the file symbol index information contained in the header part
5276 of binary archives. Performs the same function as the @option{t}
5277 command to @command{ar}, but without using the BFD library. @xref{ar}.
5279 @item -w[lLiaprmfFsOoRtUuTgAckK]
5280 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
5281 @include debug.options.texi
5284 @itemx --process-links
5285 Display the contents of non-debug sections found in separate debuginfo
5286 files that are linked to the main file. This option automatically
5287 implies the @option{-wK} option, and only sections requested by other
5288 command line options will be displayed.
5290 @include ctf.options.texi
5291 @item --ctf-symbols=@var{section}
5292 @item --ctf-strings=@var{section}
5293 Specify the name of another section from which the CTF file can inherit
5294 strings and symbols. By default, the @code{.symtab} and its linked
5295 string table are used.
5297 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
5298 other must be specified as well.
5302 Display a histogram of bucket list lengths when displaying the contents
5303 of the symbol tables.
5307 Display the version number of readelf.
5311 Don't break output lines to fit into 80 columns. By default
5312 @command{readelf} breaks section header and segment listing lines for
5313 64-bit ELF files, so that they fit into 80 columns. This option causes
5314 @command{readelf} to print each section header resp. each segment one a
5315 single line, which is far more readable on terminals wider than 80 columns.
5318 @itemx --silent-truncation
5319 Normally when readelf is displaying a symbol name, and it has to
5320 truncate the name to fit into an 80 column display, it will add a
5321 suffix of @code{[...]} to the name. This command line option
5322 disables this behaviour, allowing 5 more characters of the name to be
5323 displayed and restoring the old behaviour of readelf (prior to release
5328 Display the command-line options understood by @command{readelf}.
5335 @c man begin SEEALSO readelf
5336 objdump(1), and the Info entries for @file{binutils}.
5343 @cindex Update ELF header
5346 @c man title elfedit update ELF header and program property of ELF files
5349 @c man begin SYNOPSIS elfedit
5350 elfedit [@option{--input-mach=}@var{machine}]
5351 [@option{--input-type=}@var{type}]
5352 [@option{--input-osabi=}@var{osabi}]
5353 [@option{--input-abiversion=}@var{version}]
5354 @option{--output-mach=}@var{machine}
5355 @option{--output-type=}@var{type}
5356 @option{--output-osabi=}@var{osabi}
5357 @option{--output-abiversion=}@var{version}
5358 @option{--enable-x86-feature=}@var{feature}
5359 @option{--disable-x86-feature=}@var{feature}
5360 [@option{-v}|@option{--version}]
5361 [@option{-h}|@option{--help}]
5362 @var{elffile}@dots{}
5366 @c man begin DESCRIPTION elfedit
5368 @command{elfedit} updates the ELF header and program property of ELF
5369 files which have the matching ELF machine and file types. The options
5370 control how and which fields in the ELF header and program property
5373 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
5374 64-bit ELF files are supported, as are archives containing ELF files.
5377 @c man begin OPTIONS elfedit
5379 The long and short forms of options, shown here as alternatives, are
5380 equivalent. At least one of the @option{--output-mach},
5381 @option{--output-type}, @option{--output-osabi},
5382 @option{--output-abiversion},
5383 @option{--enable-x86-feature} and @option{--disable-x86-feature}
5384 options must be given.
5388 @item --input-mach=@var{machine}
5389 Set the matching input ELF machine type to @var{machine}. If
5390 @option{--input-mach} isn't specified, it will match any ELF
5393 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
5394 @var{K1OM} and @var{x86-64}.
5396 @item --output-mach=@var{machine}
5397 Change the ELF machine type in the ELF header to @var{machine}. The
5398 supported ELF machine types are the same as @option{--input-mach}.
5400 @item --input-type=@var{type}
5401 Set the matching input ELF file type to @var{type}. If
5402 @option{--input-type} isn't specified, it will match any ELF file types.
5404 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
5406 @item --output-type=@var{type}
5407 Change the ELF file type in the ELF header to @var{type}. The
5408 supported ELF types are the same as @option{--input-type}.
5410 @item --input-osabi=@var{osabi}
5411 Set the matching input ELF file OSABI to @var{osabi}. If
5412 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
5414 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
5415 @var{GNU}, @var{Linux} (alias for @var{GNU}),
5416 @var{Solaris}, @var{AIX}, @var{Irix},
5417 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
5418 @var{NSK}, @var{AROS} and @var{FenixOS}.
5420 @item --output-osabi=@var{osabi}
5421 Change the ELF OSABI in the ELF header to @var{osabi}. The
5422 supported ELF OSABI are the same as @option{--input-osabi}.
5424 @item --input-abiversion=@var{version}
5425 Set the matching input ELF file ABIVERSION to @var{version}.
5426 @var{version} must be between 0 and 255. If @option{--input-abiversion}
5427 isn't specified, it will match any ELF ABIVERSIONs.
5429 @item --output-abiversion=@var{version}
5430 Change the ELF ABIVERSION in the ELF header to @var{version}.
5431 @var{version} must be between 0 and 255.
5433 @item --enable-x86-feature=@var{feature}
5434 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
5435 ELF files with machine types of @var{i386} or @var{x86-64}. The
5436 supported features are, @var{ibt}, @var{shstk}, @var{lam_u48} and
5439 @item --disable-x86-feature=@var{feature}
5440 Clear the @var{feature} bit in program property in @var{exec} or
5441 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
5442 The supported features are the same as @option{--enable-x86-feature}.
5444 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
5445 are available only on hosts with @samp{mmap} support.
5449 Display the version number of @command{elfedit}.
5453 Display the command-line options understood by @command{elfedit}.
5460 @c man begin SEEALSO elfedit
5461 readelf(1), and the Info entries for @file{binutils}.
5465 @node Common Options
5466 @chapter Common Options
5468 The following command-line options are supported by all of the
5469 programs described in this manual.
5471 @c man begin OPTIONS
5473 @include at-file.texi
5477 Display the command-line options supported by the program.
5480 Display the version number of the program.
5482 @c man begin OPTIONS
5486 @node Selecting the Target System
5487 @chapter Selecting the Target System
5489 You can specify two aspects of the target system to the @sc{gnu}
5490 binary file utilities, each in several ways:
5500 In the following summaries, the lists of ways to specify values are in
5501 order of decreasing precedence. The ways listed first override those
5504 The commands to list valid values only list the values for which the
5505 programs you are running were configured. If they were configured with
5506 @option{--enable-targets=all}, the commands list most of the available
5507 values, but a few are left out; not all targets can be configured in at
5508 once because some of them can only be configured @dfn{native} (on hosts
5509 with the same type as the target system).
5512 * Target Selection::
5513 * Architecture Selection::
5516 @node Target Selection
5517 @section Target Selection
5519 A @dfn{target} is an object file format. A given target may be
5520 supported for multiple architectures (@pxref{Architecture Selection}).
5521 A target selection may also have variations for different operating
5522 systems or architectures.
5524 The command to list valid target values is @samp{objdump -i}
5525 (the first column of output contains the relevant information).
5527 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5528 @samp{a.out-sunos-big}.
5530 You can also specify a target using a configuration triplet. This is
5531 the same sort of name that is passed to @file{configure} to specify a
5532 target. When you use a configuration triplet as an argument, it must be
5533 fully canonicalized. You can see the canonical version of a triplet by
5534 running the shell script @file{config.sub} which is included with the
5537 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5538 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5540 @subheading @command{objdump} Target
5546 command-line option: @option{-b} or @option{--target}
5549 environment variable @code{GNUTARGET}
5552 deduced from the input file
5555 @subheading @command{objcopy} and @command{strip} Input Target
5561 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5564 environment variable @code{GNUTARGET}
5567 deduced from the input file
5570 @subheading @command{objcopy} and @command{strip} Output Target
5576 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5579 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5582 environment variable @code{GNUTARGET}
5585 deduced from the input file
5588 @subheading @command{nm}, @command{size}, and @command{strings} Target
5594 command-line option: @option{--target}
5597 environment variable @code{GNUTARGET}
5600 deduced from the input file
5603 @node Architecture Selection
5604 @section Architecture Selection
5606 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5607 to run. Its name may contain a colon, separating the name of the
5608 processor family from the name of the particular @sc{cpu}.
5610 The command to list valid architecture values is @samp{objdump -i} (the
5611 second column contains the relevant information).
5613 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5615 @subheading @command{objdump} Architecture
5621 command-line option: @option{-m} or @option{--architecture}
5624 deduced from the input file
5627 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5633 deduced from the input file
5638 @cindex separate debug files
5640 debuginfod is a web service that indexes ELF/DWARF debugging resources
5641 by build-id and serves them over HTTP. For more information see:
5642 @emph{https://sourceware.org/elfutils/Debuginfod.html}
5644 Binutils can be built with the debuginfod client library
5645 @code{libdebuginfod} using the @option{--with-debuginfod} configure option.
5646 This option is enabled by default if @code{libdebuginfod} is installed
5647 and found at configure time. This allows @command{objdump} and
5648 @command{readelf} to automatically query debuginfod servers for
5649 separate debug files when the files are otherwise not found.
5651 debuginfod is packaged with elfutils, starting with version 0.178.
5652 You can get the latest version from `https://sourceware.org/elfutils/'.
5654 The DWARF info dumping tools (@command{readelf} and @command{objdump})
5655 have options to control when they should access the debuginfod
5656 servers. By default this access is enabled.
5658 @node Reporting Bugs
5659 @chapter Reporting Bugs
5661 @cindex reporting bugs
5663 Your bug reports play an essential role in making the binary utilities
5666 Reporting a bug may help you by bringing a solution to your problem, or
5667 it may not. But in any case the principal function of a bug report is
5668 to help the entire community by making the next version of the binary
5669 utilities work better. Bug reports are your contribution to their
5672 In order for a bug report to serve its purpose, you must include the
5673 information that enables us to fix the bug.
5676 * Bug Criteria:: Have you found a bug?
5677 * Bug Reporting:: How to report bugs
5681 @section Have You Found a Bug?
5682 @cindex bug criteria
5684 If you are not sure whether you have found a bug, here are some guidelines:
5687 @cindex fatal signal
5690 If a binary utility gets a fatal signal, for any input whatever, that is
5691 a bug. Reliable utilities never crash.
5693 @cindex error on valid input
5695 If a binary utility produces an error message for valid input, that is a
5699 If you are an experienced user of binary utilities, your suggestions for
5700 improvement are welcome in any case.
5704 @section How to Report Bugs
5706 @cindex bugs, reporting
5708 A number of companies and individuals offer support for @sc{gnu}
5709 products. If you obtained the binary utilities from a support
5710 organization, we recommend you contact that organization first.
5712 You can find contact information for many support companies and
5713 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5717 In any event, we also recommend that you send bug reports for the binary
5718 utilities to @value{BUGURL}.
5721 The fundamental principle of reporting bugs usefully is this:
5722 @strong{report all the facts}. If you are not sure whether to state a
5723 fact or leave it out, state it!
5725 Often people omit facts because they think they know what causes the
5726 problem and assume that some details do not matter. Thus, you might
5727 assume that the name of a file you use in an example does not matter.
5728 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5729 a stray memory reference which happens to fetch from the location where
5730 that pathname is stored in memory; perhaps, if the pathname were
5731 different, the contents of that location would fool the utility into
5732 doing the right thing despite the bug. Play it safe and give a
5733 specific, complete example. That is the easiest thing for you to do,
5734 and the most helpful.
5736 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5737 it is new to us. Therefore, always write your bug reports on the assumption
5738 that the bug has not been reported previously.
5740 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5741 bell?'' This cannot help us fix a bug, so it is basically useless. We
5742 respond by asking for enough details to enable us to investigate.
5743 You might as well expedite matters by sending them to begin with.
5745 To enable us to fix the bug, you should include all these things:
5749 The version of the utility. Each utility announces it if you start it
5750 with the @option{--version} argument.
5752 Without this, we will not know whether there is any point in looking for
5753 the bug in the current version of the binary utilities.
5756 Any patches you may have applied to the source, including any patches
5757 made to the @code{BFD} library.
5760 The type of machine you are using, and the operating system name and
5764 What compiler (and its version) was used to compile the utilities---e.g.
5768 The command arguments you gave the utility to observe the bug. To
5769 guarantee you will not omit something important, list them all. A copy
5770 of the Makefile (or the output from make) is sufficient.
5772 If we were to try to guess the arguments, we would probably guess wrong
5773 and then we might not encounter the bug.
5776 A complete input file, or set of input files, that will reproduce the
5777 bug. If the utility is reading an object file or files, then it is
5778 generally most helpful to send the actual object files.
5780 If the source files were produced exclusively using @sc{gnu} programs
5781 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5782 may be OK to send the source files rather than the object files. In
5783 this case, be sure to say exactly what version of @command{gcc}, or
5784 whatever, was used to produce the object files. Also say how
5785 @command{gcc}, or whatever, was configured.
5788 A description of what behavior you observe that you believe is
5789 incorrect. For example, ``It gets a fatal signal.''
5791 Of course, if the bug is that the utility gets a fatal signal, then we
5792 will certainly notice it. But if the bug is incorrect output, we might
5793 not notice unless it is glaringly wrong. You might as well not give us
5794 a chance to make a mistake.
5796 Even if the problem you experience is a fatal signal, you should still
5797 say so explicitly. Suppose something strange is going on, such as your
5798 copy of the utility is out of sync, or you have encountered a bug in
5799 the C library on your system. (This has happened!) Your copy might
5800 crash and ours would not. If you told us to expect a crash, then when
5801 ours fails to crash, we would know that the bug was not happening for
5802 us. If you had not told us to expect a crash, then we would not be able
5803 to draw any conclusion from our observations.
5806 If you wish to suggest changes to the source, send us context diffs, as
5807 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5808 option. Always send diffs from the old file to the new file. If you
5809 wish to discuss something in the @command{ld} source, refer to it by
5810 context, not by line number.
5812 The line numbers in our development sources will not match those in your
5813 sources. Your line numbers would convey no useful information to us.
5816 Here are some things that are not necessary:
5820 A description of the envelope of the bug.
5822 Often people who encounter a bug spend a lot of time investigating
5823 which changes to the input file will make the bug go away and which
5824 changes will not affect it.
5826 This is often time consuming and not very useful, because the way we
5827 will find the bug is by running a single example under the debugger
5828 with breakpoints, not by pure deduction from a series of examples.
5829 We recommend that you save your time for something else.
5831 Of course, if you can find a simpler example to report @emph{instead}
5832 of the original one, that is a convenience for us. Errors in the
5833 output will be easier to spot, running under the debugger will take
5834 less time, and so on.
5836 However, simplification is not vital; if you do not want to do this,
5837 report the bug anyway and send us the entire test case you used.
5840 A patch for the bug.
5842 A patch for the bug does help us if it is a good one. But do not omit
5843 the necessary information, such as the test case, on the assumption that
5844 a patch is all we need. We might see problems with your patch and decide
5845 to fix the problem another way, or we might not understand it at all.
5847 Sometimes with programs as complicated as the binary utilities it is
5848 very hard to construct an example that will make the program follow a
5849 certain path through the code. If you do not send us the example, we
5850 will not be able to construct one, so we will not be able to verify that
5853 And if we cannot understand what bug you are trying to fix, or why your
5854 patch should be an improvement, we will not install it. A test case will
5855 help us to understand.
5858 A guess about what the bug is or what it depends on.
5860 Such guesses are usually wrong. Even we cannot guess right about such
5861 things without first using the debugger to find the facts.
5864 @node GNU Free Documentation License
5865 @appendix GNU Free Documentation License
5869 @node Binutils Index
5870 @unnumbered Binutils Index