1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2019 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 into file names and line numbers
124 Manipulate Windows resources
127 Generator for Windows message resources
130 Create the files needed to build and use Dynamic Link Libraries
134 This document is distributed under the terms of the GNU Free
135 Documentation License version 1.3. A copy of the license is included
136 in the section entitled ``GNU Free Documentation License''.
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * size:: List section sizes and total size
145 * strings:: List printable strings from files
146 * strip:: Discard symbols
147 * c++filt:: Filter to demangle encoded C++ symbols
148 * cxxfilt: c++filt. MS-DOS name for c++filt
149 * addr2line:: Convert addresses to file and line
150 * windmc:: Generator for Windows message resources
151 * windres:: Manipulate Windows resources
152 * dlltool:: Create files needed to build and use DLLs
153 * readelf:: Display the contents of ELF format files
154 * elfedit:: Update 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 * Reporting Bugs:: Reporting Bugs
158 * GNU Free Documentation License:: GNU Free Documentation License
159 * Binutils Index:: Binutils Index
167 @cindex collections of files
169 @c man title ar create, modify, and extract from archives
172 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
173 ar -M [ <mri-script ]
176 @c man begin DESCRIPTION ar
178 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
179 archives. An @dfn{archive} is a single file holding a collection of
180 other files in a structure that makes it possible to retrieve
181 the original individual files (called @dfn{members} of the archive).
183 The original files' contents, mode (permissions), timestamp, owner, and
184 group are preserved in the archive, and can be restored on
188 @sc{gnu} @command{ar} can maintain archives whose members have names of any
189 length; however, depending on how @command{ar} is configured on your
190 system, a limit on member-name length may be imposed for compatibility
191 with archive formats maintained with other tools. If it exists, the
192 limit is often 15 characters (typical of formats related to a.out) or 16
193 characters (typical of formats related to coff).
196 @command{ar} is considered a binary utility because archives of this sort
197 are most often used as @dfn{libraries} holding commonly needed
201 @command{ar} creates an index to the symbols defined in relocatable
202 object modules in the archive when you specify the modifier @samp{s}.
203 Once created, this index is updated in the archive whenever @command{ar}
204 makes a change to its contents (save for the @samp{q} update operation).
205 An archive with such an index speeds up linking to the library, and
206 allows routines in the library to call each other without regard to
207 their placement in the archive.
209 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
210 table. If an archive lacks the table, another form of @command{ar} called
211 @command{ranlib} can be used to add just the table.
213 @cindex thin archives
214 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
215 which contains a symbol index and references to the original copies
216 of the member files of the archive. This is useful for building
217 libraries for use within a local build tree, where the relocatable
218 objects are expected to remain available, and copying the contents of
219 each object would only waste time and space.
221 An archive can either be @emph{thin} or it can be normal. It cannot
222 be both at the same time. Once an archive is created its format
223 cannot be changed without first deleting it and then creating a new
224 archive in its place.
226 Thin archives are also @emph{flattened}, so that adding one thin
227 archive to another thin archive does not nest it, as would happen with
228 a normal archive. Instead the elements of the first archive are added
229 individually to the second archive.
231 The paths to the elements of the archive are stored relative to the
234 @cindex compatibility, @command{ar}
235 @cindex @command{ar} compatibility
236 @sc{gnu} @command{ar} is designed to be compatible with two different
237 facilities. You can control its activity using command-line options,
238 like the different varieties of @command{ar} on Unix systems; or, if you
239 specify the single command-line option @option{-M}, you can control it
240 with a script supplied via standard input, like the MRI ``librarian''
246 * ar cmdline:: Controlling @command{ar} on the command line
247 * ar scripts:: Controlling @command{ar} with a script
252 @section Controlling @command{ar} on the Command Line
255 @c man begin SYNOPSIS ar
256 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
260 @cindex Unix compatibility, @command{ar}
261 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
262 arguments to execute: one keyletter specifying the @emph{operation}
263 (optionally accompanied by other keyletters specifying
264 @emph{modifiers}), and the archive name to act on.
266 Most operations can also accept further @var{member} arguments,
267 specifying particular files to operate on.
269 @c man begin OPTIONS ar
271 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
272 flags @var{mod} in any order, within the first command-line argument.
274 If you wish, you may begin the first command-line argument with a
277 @cindex operations on archive
278 The @var{p} keyletter specifies what operation to execute; it may be
279 any of the following, but you must specify only one of them:
283 @cindex deleting from archive
284 @emph{Delete} modules from the archive. Specify the names of modules to
285 be deleted as @var{member}@dots{}; the archive is untouched if you
286 specify no files to delete.
288 If you specify the @samp{v} modifier, @command{ar} lists each module
292 @cindex moving in archive
293 Use this operation to @emph{move} members in an archive.
295 The ordering of members in an archive can make a difference in how
296 programs are linked using the library, if a symbol is defined in more
299 If no modifiers are used with @code{m}, any members you name in the
300 @var{member} arguments are moved to the @emph{end} of the archive;
301 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
302 specified place instead.
305 @cindex printing from archive
306 @emph{Print} the specified members of the archive, to the standard
307 output file. If the @samp{v} modifier is specified, show the member
308 name before copying its contents to standard output.
310 If you specify no @var{member} arguments, all the files in the archive are
314 @cindex quick append to archive
315 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
316 @var{archive}, without checking for replacement.
318 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
319 operation; new members are always placed at the end of the archive.
321 The modifier @samp{v} makes @command{ar} list each file as it is appended.
323 Since the point of this operation is speed, implementations of
324 @command{ar} have the option of not updating the archive's symbol
325 table if one exists. Too many different systems however assume that
326 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
327 rebuild the table even with a quick append.
329 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
330 synonym for @samp{r} - replacing already existing files in the
331 archive and appending new ones at the end.
334 @cindex replacement in archive
335 Insert the files @var{member}@dots{} into @var{archive} (with
336 @emph{replacement}). This operation differs from @samp{q} in that any
337 previously existing members are deleted if their names match those being
340 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
341 displays an error message, and leaves undisturbed any existing members
342 of the archive matching that name.
344 By default, new members are added at the end of the file; but you may
345 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
346 placement relative to some existing member.
348 The modifier @samp{v} used with this operation elicits a line of
349 output for each file inserted, along with one of the letters @samp{a} or
350 @samp{r} to indicate whether the file was appended (no old member
351 deleted) or replaced.
355 Add an index to the archive, or update it if it already exists. Note
356 this command is an exception to the rule that there can only be one
357 command letter, as it is possible to use it as either a command or a
358 modifier. In either case it does the same thing.
361 @cindex contents of archive
362 Display a @emph{table} listing the contents of @var{archive}, or those
363 of the files listed in @var{member}@dots{} that are present in the
364 archive. Normally only the member name is shown, but if the modifier
365 @samp{O} is specified, then the corresponding offset of the member is also
366 displayed. Finally, in order to see the modes (permissions), timestamp,
367 owner, group, and size the @samp{v} modifier should be included.
369 If you do not specify a @var{member}, all files in the archive
372 @cindex repeated names in archive
373 @cindex name duplication in archive
374 If there is more than one file with the same name (say, @samp{fie}) in
375 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
376 first instance; to see them all, you must ask for a complete
377 listing---in our example, @samp{ar t b.a}.
378 @c WRS only; per Gumby, this is implementation-dependent, and in a more
379 @c recent case in fact works the other way.
382 @cindex extract from archive
383 @emph{Extract} members (named @var{member}) from the archive. You can
384 use the @samp{v} modifier with this operation, to request that
385 @command{ar} list each name as it extracts it.
387 If you do not specify a @var{member}, all files in the archive
390 Files cannot be extracted from a thin archive, and there are
391 restrictions on extracting from archives created with @option{P}: The
392 paths must not be absolute, may not contain @code{..}, and any
393 subdirectories in the paths must exist.
396 A number of modifiers (@var{mod}) may immediately follow the @var{p}
397 keyletter, to specify variations on an operation's behavior:
401 @cindex relative placement in archive
402 Add new files @emph{after} an existing member of the
403 archive. If you use the modifier @samp{a}, the name of an existing archive
404 member must be present as the @var{relpos} argument, before the
405 @var{archive} specification.
408 Add new files @emph{before} an existing member of the
409 archive. If you use the modifier @samp{b}, the name of an existing archive
410 member must be present as the @var{relpos} argument, before the
411 @var{archive} specification. (same as @samp{i}).
414 @cindex creating archives
415 @emph{Create} the archive. The specified @var{archive} is always
416 created if it did not exist, when you request an update. But a warning is
417 issued unless you specify in advance that you expect to create it, by
421 @cindex deterministic archives
422 @kindex --enable-deterministic-archives
423 Operate in @emph{deterministic} mode. When adding files and the archive
424 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
425 for all files. When this option is used, if @command{ar} is used with
426 identical options and identical input files, multiple runs will create
427 identical output files regardless of the input files' owners, groups,
428 file modes, or modification times.
430 If @file{binutils} was configured with
431 @option{--enable-deterministic-archives}, then this mode is on by default.
432 It can be disabled with the @samp{U} modifier, below.
435 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
436 names of any length. This will cause it to create archives which are
437 not compatible with the native @command{ar} program on some systems. If
438 this is a concern, the @samp{f} modifier may be used to truncate file
439 names when putting them in the archive.
442 Insert new files @emph{before} an existing member of the
443 archive. If you use the modifier @samp{i}, the name of an existing archive
444 member must be present as the @var{relpos} argument, before the
445 @var{archive} specification. (same as @samp{b}).
448 This modifier is accepted but not used.
449 @c whaffor ar l modifier??? presumably compat; with
450 @c what???---doc@@cygnus.com, 25jan91
453 Uses the @var{count} parameter. This is used if there are multiple
454 entries in the archive with the same name. Extract or delete instance
455 @var{count} of the given name from the archive.
458 @cindex dates in archive
459 Preserve the @emph{original} dates of members when extracting them. If
460 you do not specify this modifier, files extracted from the archive
461 are stamped with the time of extraction.
464 @cindex offsets of files
465 Display member offsets inside the archive. Use together with the @samp{t}
469 Use the full path name when matching or storing names in the archive.
470 Archives created with full path names are not POSIX compliant, and
471 thus may not work with tools other than up to date @sc{gnu} tools.
472 Modifying such archives with @sc{gnu} @command{ar} without using
473 @option{P} will remove the full path names unless the archive is a
474 thin archive. Note that @option{P} may be useful when adding files to
475 a thin archive since @option{r} without @option{P} ignores the path
476 when choosing which element to replace. Thus
478 ar rcST archive.a subdir/file1 subdir/file2 file1
480 will result in the first @code{subdir/file1} being replaced with
481 @code{file1} from the current directory. Adding @option{P} will
482 prevent this replacement.
485 @cindex writing archive index
486 Write an object-file index into the archive, or update an existing one,
487 even if no other change is made to the archive. You may use this modifier
488 flag either with any operation, or alone. Running @samp{ar s} on an
489 archive is equivalent to running @samp{ranlib} on it.
492 @cindex not writing archive index
493 Do not generate an archive symbol table. This can speed up building a
494 large library in several steps. The resulting archive can not be used
495 with the linker. In order to build a symbol table, you must omit the
496 @samp{S} modifier on the last execution of @samp{ar}, or you must run
497 @samp{ranlib} on the archive.
500 @cindex creating thin archive
501 Make the specified @var{archive} a @emph{thin} archive. If it already
502 exists and is a regular archive, the existing members must be present
503 in the same directory as @var{archive}.
506 @cindex updating an archive
507 Normally, @samp{ar r}@dots{} inserts all files
508 listed into the archive. If you would like to insert @emph{only} those
509 of the files you list that are newer than existing members of the same
510 names, use this modifier. The @samp{u} modifier is allowed only for the
511 operation @samp{r} (replace). In particular, the combination @samp{qu} is
512 not allowed, since checking the timestamps would lose any speed
513 advantage from the operation @samp{q}.
516 @cindex deterministic archives
517 @kindex --enable-deterministic-archives
518 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
519 of the @samp{D} modifier, above: added files and the archive index will
520 get their actual UID, GID, timestamp, and file mode values.
522 This is the default unless @file{binutils} was configured with
523 @option{--enable-deterministic-archives}.
526 This modifier requests the @emph{verbose} version of an operation. Many
527 operations display additional information, such as filenames processed,
528 when the modifier @samp{v} is appended.
531 This modifier shows the version number of @command{ar}.
534 The @command{ar} program also supports some command-line options which
535 are neither modifiers nor actions, but which do change its behaviour
540 Displays the list of command-line options supported by @command{ar}
544 Displays the version information of @command{ar} and then exits.
547 @command{ar} ignores an initial option spelled @samp{-X32_64}, for
548 compatibility with AIX. The behaviour produced by this option is the
549 default for @sc{gnu} @command{ar}. @command{ar} does not support any
550 of the other @samp{-X} options; in particular, it does not support
551 @option{-X32} which is the default for AIX @command{ar}.
553 @item --plugin @var{name}
555 The optional command-line switch @option{--plugin @var{name}} causes
556 @command{ar} to load the plugin called @var{name} which adds support
557 for more file formats, including object files with link-time
558 optimization information.
560 This option is only available if the toolchain has been built with
561 plugin support enabled.
563 If @option{--plugin} is not provided, but plugin support has been
564 enabled then @command{ar} iterates over the files in
565 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
566 plugin that claims the object in question is used.
568 Please note that this plugin search directory is @emph{not} the one
569 used by @command{ld}'s @option{-plugin} option. In order to make
570 @command{ar} use the linker plugin it must be copied into the
571 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
572 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
573 based compilations it is called @file{LLVMgold.so}. The GCC plugin
574 is always backwards compatible with earlier versions, so it is
575 sufficient to just copy the newest one.
577 @item --target @var{target}
578 The optional command-line switch @option{--target @var{bfdname}}
579 specifies that the archive members are in an object code format
580 different from your system's default format. See
581 @xref{Target Selection}, for more information.
586 @c man begin SEEALSO ar
587 nm(1), ranlib(1), and the Info entries for @file{binutils}.
592 @section Controlling @command{ar} with a Script
595 ar -M [ <@var{script} ]
598 @cindex MRI compatibility, @command{ar}
599 @cindex scripts, @command{ar}
600 If you use the single command-line option @samp{-M} with @command{ar}, you
601 can control its operation with a rudimentary command language. This
602 form of @command{ar} operates interactively if standard input is coming
603 directly from a terminal. During interactive use, @command{ar} prompts for
604 input (the prompt is @samp{AR >}), and continues executing even after
605 errors. If you redirect standard input to a script file, no prompts are
606 issued, and @command{ar} abandons execution (with a nonzero exit code)
609 The @command{ar} command language is @emph{not} designed to be equivalent
610 to the command-line options; in fact, it provides somewhat less control
611 over archives. The only purpose of the command language is to ease the
612 transition to @sc{gnu} @command{ar} for developers who already have scripts
613 written for the MRI ``librarian'' program.
615 The syntax for the @command{ar} command language is straightforward:
618 commands are recognized in upper or lower case; for example, @code{LIST}
619 is the same as @code{list}. In the following descriptions, commands are
620 shown in upper case for clarity.
623 a single command may appear on each line; it is the first word on the
627 empty lines are allowed, and have no effect.
630 comments are allowed; text after either of the characters @samp{*}
631 or @samp{;} is ignored.
634 Whenever you use a list of names as part of the argument to an @command{ar}
635 command, you can separate the individual names with either commas or
636 blanks. Commas are shown in the explanations below, for clarity.
639 @samp{+} is used as a line continuation character; if @samp{+} appears
640 at the end of a line, the text on the following line is considered part
641 of the current command.
644 Here are the commands you can use in @command{ar} scripts, or when using
645 @command{ar} interactively. Three of them have special significance:
647 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
648 a temporary file required for most of the other commands.
650 @code{SAVE} commits the changes so far specified by the script. Prior
651 to @code{SAVE}, commands affect only the temporary copy of the current
655 @item ADDLIB @var{archive}
656 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
657 Add all the contents of @var{archive} (or, if specified, each named
658 @var{module} from @var{archive}) to the current archive.
660 Requires prior use of @code{OPEN} or @code{CREATE}.
662 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
663 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
664 @c else like "ar q..."
665 Add each named @var{member} as a module in the current archive.
667 Requires prior use of @code{OPEN} or @code{CREATE}.
670 Discard the contents of the current archive, canceling the effect of
671 any operations since the last @code{SAVE}. May be executed (with no
672 effect) even if no current archive is specified.
674 @item CREATE @var{archive}
675 Creates an archive, and makes it the current archive (required for many
676 other commands). The new archive is created with a temporary name; it
677 is not actually saved as @var{archive} until you use @code{SAVE}.
678 You can overwrite existing archives; similarly, the contents of any
679 existing file named @var{archive} will not be destroyed until @code{SAVE}.
681 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
682 Delete each listed @var{module} from the current archive; equivalent to
683 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
685 Requires prior use of @code{OPEN} or @code{CREATE}.
687 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
688 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
689 List each named @var{module} present in @var{archive}. The separate
690 command @code{VERBOSE} specifies the form of the output: when verbose
691 output is off, output is like that of @samp{ar -t @var{archive}
692 @var{module}@dots{}}. When verbose output is on, the listing is like
693 @samp{ar -tv @var{archive} @var{module}@dots{}}.
695 Output normally goes to the standard output stream; however, if you
696 specify @var{outputfile} as a final argument, @command{ar} directs the
700 Exit from @command{ar}, with a @code{0} exit code to indicate successful
701 completion. This command does not save the output file; if you have
702 changed the current archive since the last @code{SAVE} command, those
705 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
706 Extract each named @var{module} from the current archive, writing them
707 into the current directory as separate files. Equivalent to @samp{ar -x
708 @var{archive} @var{module}@dots{}}.
710 Requires prior use of @code{OPEN} or @code{CREATE}.
713 @c FIXME Tokens but no commands???
720 Display full contents of the current archive, in ``verbose'' style
721 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
722 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
723 enhancement, rather than present for MRI compatibility.)
725 Requires prior use of @code{OPEN} or @code{CREATE}.
727 @item OPEN @var{archive}
728 Opens an existing archive for use as the current archive (required for
729 many other commands). Any changes as the result of subsequent commands
730 will not actually affect @var{archive} until you next use @code{SAVE}.
732 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
733 In the current archive, replace each existing @var{module} (named in
734 the @code{REPLACE} arguments) from files in the current working directory.
735 To execute this command without errors, both the file, and the module in
736 the current archive, must exist.
738 Requires prior use of @code{OPEN} or @code{CREATE}.
741 Toggle an internal flag governing the output from @code{DIRECTORY}.
742 When the flag is on, @code{DIRECTORY} output matches output from
743 @samp{ar -tv }@dots{}.
746 Commit your changes to the current archive, and actually save it as a
747 file with the name specified in the last @code{CREATE} or @code{OPEN}
750 Requires prior use of @code{OPEN} or @code{CREATE}.
759 The @sc{gnu} linker @command{ld} is now described in a separate manual.
760 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
768 @c man title nm list symbols from object files
771 @c man begin SYNOPSIS nm
772 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
773 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
774 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
775 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
776 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
777 [@option{-n}|@option{-v}|@option{--numeric-sort}]
778 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
779 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
780 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
781 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
782 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
783 [@option{--plugin} @var{name}]
784 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
785 [@option{--size-sort}] [@option{--special-syms}]
786 [@option{--synthetic}] [@option{--with-symbol-versions}] [@option{--target=}@var{bfdname}]
787 [@var{objfile}@dots{}]
791 @c man begin DESCRIPTION nm
792 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
793 If no object files are listed as arguments, @command{nm} assumes the file
796 For each symbol, @command{nm} shows:
800 The symbol value, in the radix selected by options (see below), or
801 hexadecimal by default.
804 The symbol type. At least the following types are used; others are, as
805 well, depending on the object file format. If lowercase, the symbol is
806 usually local; if uppercase, the symbol is global (external). There
807 are however a few lowercase symbols that are shown for special global
808 symbols (@code{u}, @code{v} and @code{w}).
810 @c Some more detail on exactly what these symbol types are used for
814 The symbol's value is absolute, and will not be changed by further
819 The symbol is in the BSS data section. This section typically
820 contains zero-initialized or uninitialized data, although the exact
821 behavior is system dependent.
824 The symbol is common. Common symbols are uninitialized data. When
825 linking, multiple common symbols may appear with the same name. If the
826 symbol is defined anywhere, the common symbols are treated as undefined
829 For more details on common symbols, see the discussion of
830 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
835 The symbol is in the initialized data section.
839 The symbol is in an initialized data section for small objects. Some
840 object file formats permit more efficient access to small data objects,
841 such as a global int variable as opposed to a large global array.
844 For PE format files this indicates that the symbol is in a section
845 specific to the implementation of DLLs. For ELF format files this
846 indicates that the symbol is an indirect function. This is a GNU
847 extension to the standard set of ELF symbol types. It indicates a
848 symbol which if referenced by a relocation does not evaluate to its
849 address, but instead must be invoked at runtime. The runtime
850 execution will then return the value to be used in the relocation.
853 The symbol is an indirect reference to another symbol.
856 The symbol is a debugging symbol.
859 The symbol is in the read-only data section.
862 The symbol is in a stack unwind section.
866 The symbol is in a read only data section.
870 The symbol is in an uninitialized or zero-initialized data section
875 The symbol is in the text (code) section.
878 The symbol is undefined.
881 The symbol is a unique global symbol. This is a GNU extension to the
882 standard set of ELF symbol bindings. For such a symbol the dynamic linker
883 will make sure that in the entire process there is just one symbol with
884 this name and type in use.
888 The symbol is a weak object. When a weak defined symbol is linked with
889 a normal defined symbol, the normal defined symbol is used with no error.
890 When a weak undefined symbol is linked and the symbol is not defined,
891 the value of the weak symbol becomes zero with no error. On some
892 systems, uppercase indicates that a default value has been specified.
896 The symbol is a weak symbol that has not been specifically tagged as a
897 weak object symbol. When a weak defined symbol is linked with a normal
898 defined symbol, the normal defined symbol is used with no error.
899 When a weak undefined symbol is linked and the symbol is not defined,
900 the value of the symbol is determined in a system-specific manner without
901 error. On some systems, uppercase indicates that a default value has been
905 The symbol is a stabs symbol in an a.out object file. In this case, the
906 next values printed are the stabs other field, the stabs desc field, and
907 the stab type. Stabs symbols are used to hold debugging information.
910 The symbol type is unknown, or object file format specific.
919 @c man begin OPTIONS nm
920 The long and short forms of options, shown here as alternatives, are
926 @itemx --print-file-name
927 @cindex input file name
929 @cindex source file name
930 Precede each symbol by the name of the input file (or archive member)
931 in which it was found, rather than identifying the input file once only,
932 before all of its symbols.
936 @cindex debugging symbols
937 Display all symbols, even debugger-only symbols; normally these are not
941 @cindex @command{nm} format
942 @cindex @command{nm} compatibility
943 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
946 @itemx --demangle[=@var{style}]
947 @cindex demangling in nm
948 Decode (@dfn{demangle}) low-level symbol names into user-level names.
949 Besides removing any initial underscore prepended by the system, this
950 makes C++ function names readable. Different compilers have different
951 mangling styles. The optional demangling style argument can be used to
952 choose an appropriate demangling style for your compiler. @xref{c++filt},
953 for more information on demangling.
956 Do not demangle low-level symbol names. This is the default.
958 @item --recurse-limit
959 @itemx --no-recurse-limit
960 @itemx --recursion-limit
961 @itemx --no-recursion-limit
962 Enables or disables a limit on the amount of recursion performed
963 whilst demangling strings. Since the name mangling formats allow for
964 an inifinite level of recursion it is possible to create strings whose
965 decoding will exhaust the amount of stack space available on the host
966 machine, triggering a memory fault. The limit tries to prevent this
967 from happening by restricting recursion to 2048 levels of nesting.
969 The default is for this limit to be enabled, but disabling it may be
970 necessary in order to demangle truly complicated names. Note however
971 that if the recursion limit is disabled then stack exhaustion is
972 possible and any bug reports about such an event will be rejected.
976 @cindex dynamic symbols
977 Display the dynamic symbols rather than the normal symbols. This is
978 only meaningful for dynamic objects, such as certain types of shared
981 @item -f @var{format}
982 @itemx --format=@var{format}
983 @cindex @command{nm} format
984 @cindex @command{nm} compatibility
985 Use the output format @var{format}, which can be @code{bsd},
986 @code{sysv}, or @code{posix}. The default is @code{bsd}.
987 Only the first character of @var{format} is significant; it can be
988 either upper or lower case.
992 @cindex external symbols
993 Display only external symbols.
997 Show a summary of the options to @command{nm} and exit.
1000 @itemx --line-numbers
1001 @cindex symbol line numbers
1002 For each symbol, use debugging information to try to find a filename and
1003 line number. For a defined symbol, look for the line number of the
1004 address of the symbol. For an undefined symbol, look for the line
1005 number of a relocation entry which refers to the symbol. If line number
1006 information can be found, print it after the other symbol information.
1009 @cindex objdump inlines
1010 When option @option{-l} is active, if the address belongs to a
1011 function that was inlined, then this option causes the source
1012 information for all enclosing scopes back to the first non-inlined
1013 function to be printed as well. For example, if @code{main} inlines
1014 @code{callee1} which inlines @code{callee2}, and address is from
1015 @code{callee2}, the source information for @code{callee1} and @code{main}
1016 will also be printed.
1020 @itemx --numeric-sort
1021 Sort symbols numerically by their addresses, rather than alphabetically
1026 @cindex sorting symbols
1027 Do not bother to sort the symbols in any order; print them in the order
1031 @itemx --portability
1032 Use the POSIX.2 standard output format instead of the default format.
1033 Equivalent to @samp{-f posix}.
1036 @itemx --reverse-sort
1037 Reverse the order of the sort (whether numeric or alphabetic); let the
1042 Print both value and size of defined symbols for the @code{bsd} output style.
1043 This option has no effect for object formats that do not record symbol
1044 sizes, unless @samp{--size-sort} is also used in which case a
1045 calculated size is displayed.
1048 @itemx --print-armap
1049 @cindex symbol index, listing
1050 When listing symbols from archive members, include the index: a mapping
1051 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1052 contain definitions for which names.
1054 @item -t @var{radix}
1055 @itemx --radix=@var{radix}
1056 Use @var{radix} as the radix for printing the symbol values. It must be
1057 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1060 @itemx --undefined-only
1061 @cindex external symbols
1062 @cindex undefined symbols
1063 Display only undefined symbols (those external to each object file).
1067 Show the version number of @command{nm} and exit.
1070 This option is ignored for compatibility with the AIX version of
1071 @command{nm}. It takes one parameter which must be the string
1072 @option{32_64}. The default mode of AIX @command{nm} corresponds
1073 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1075 @item --defined-only
1076 @cindex external symbols
1077 @cindex undefined symbols
1078 Display only defined symbols for each object file.
1080 @item --plugin @var{name}
1082 Load the plugin called @var{name} to add support for extra target
1083 types. This option is only available if the toolchain has been built
1084 with plugin support enabled.
1086 If @option{--plugin} is not provided, but plugin support has been
1087 enabled then @command{nm} iterates over the files in
1088 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1089 plugin that claims the object in question is used.
1091 Please note that this plugin search directory is @emph{not} the one
1092 used by @command{ld}'s @option{-plugin} option. In order to make
1093 @command{nm} use the linker plugin it must be copied into the
1094 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1095 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1096 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1097 is always backwards compatible with earlier versions, so it is
1098 sufficient to just copy the newest one.
1101 Sort symbols by size. For ELF objects symbol sizes are read from the
1102 ELF, for other object types the symbol sizes are computed as the
1103 difference between the value of the symbol and the value of the symbol
1104 with the next higher value. If the @code{bsd} output format is used
1105 the size of the symbol is printed, rather than the value, and
1106 @samp{-S} must be used in order both size and value to be printed.
1108 @item --special-syms
1109 Display symbols which have a target-specific special meaning. These
1110 symbols are usually used by the target for some special processing and
1111 are not normally helpful when included in the normal symbol lists.
1112 For example for ARM targets this option would skip the mapping symbols
1113 used to mark transitions between ARM code, THUMB code and data.
1116 Include synthetic symbols in the output. These are special symbols
1117 created by the linker for various purposes. They are not shown by
1118 default since they are not part of the binary's original source code.
1120 @item --with-symbol-versions
1121 Enables the display of symbol version information if any exists. The
1122 version string is displayed as a suffix to the symbol name, preceeded by
1123 an @@ character. For example @samp{foo@@VER_1}. If the version is
1124 the default version to be used when resolving unversioned references
1125 to the symbol then it is displayed as a suffix preceeded by two @@
1126 characters. For example @samp{foo@@@@VER_2}.
1128 @item --target=@var{bfdname}
1129 @cindex object code format
1130 Specify an object code format other than your system's default format.
1131 @xref{Target Selection}, for more information.
1138 @c man begin SEEALSO nm
1139 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1146 @c man title objcopy copy and translate object files
1149 @c man begin SYNOPSIS objcopy
1150 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1151 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1152 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1153 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1154 [@option{-S}|@option{--strip-all}]
1155 [@option{-g}|@option{--strip-debug}]
1156 [@option{--strip-unneeded}]
1157 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1158 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1159 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1160 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1161 [@option{--localize-hidden}]
1162 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1163 [@option{--globalize-symbol=}@var{symbolname}]
1164 [@option{--globalize-symbols=}@var{filename}]
1165 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1166 [@option{-w}|@option{--wildcard}]
1167 [@option{-x}|@option{--discard-all}]
1168 [@option{-X}|@option{--discard-locals}]
1169 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1170 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1171 [@option{--interleave-width=}@var{width}]
1172 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1173 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1174 [@option{--remove-relocations=}@var{sectionpattern}]
1175 [@option{-p}|@option{--preserve-dates}]
1176 [@option{-D}|@option{--enable-deterministic-archives}]
1177 [@option{-U}|@option{--disable-deterministic-archives}]
1178 [@option{--debugging}]
1179 [@option{--gap-fill=}@var{val}]
1180 [@option{--pad-to=}@var{address}]
1181 [@option{--set-start=}@var{val}]
1182 [@option{--adjust-start=}@var{incr}]
1183 [@option{--change-addresses=}@var{incr}]
1184 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1185 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1186 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1187 [@option{--change-warnings}] [@option{--no-change-warnings}]
1188 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1189 [@option{--set-section-alignment} @var{sectionpattern}=@var{align}]
1190 [@option{--add-section} @var{sectionname}=@var{filename}]
1191 [@option{--dump-section} @var{sectionname}=@var{filename}]
1192 [@option{--update-section} @var{sectionname}=@var{filename}]
1193 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1194 [@option{--long-section-names} @{enable,disable,keep@}]
1195 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1196 [@option{--reverse-bytes=}@var{num}]
1197 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1198 [@option{--redefine-sym} @var{old}=@var{new}]
1199 [@option{--redefine-syms=}@var{filename}]
1201 [@option{--keep-symbols=}@var{filename}]
1202 [@option{--strip-symbols=}@var{filename}]
1203 [@option{--strip-unneeded-symbols=}@var{filename}]
1204 [@option{--keep-global-symbols=}@var{filename}]
1205 [@option{--localize-symbols=}@var{filename}]
1206 [@option{--weaken-symbols=}@var{filename}]
1207 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1208 [@option{--alt-machine-code=}@var{index}]
1209 [@option{--prefix-symbols=}@var{string}]
1210 [@option{--prefix-sections=}@var{string}]
1211 [@option{--prefix-alloc-sections=}@var{string}]
1212 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1213 [@option{--keep-file-symbols}]
1214 [@option{--only-keep-debug}]
1215 [@option{--strip-dwo}]
1216 [@option{--extract-dwo}]
1217 [@option{--extract-symbol}]
1218 [@option{--writable-text}]
1219 [@option{--readonly-text}]
1222 [@option{--file-alignment=}@var{num}]
1223 [@option{--heap=}@var{size}]
1224 [@option{--image-base=}@var{address}]
1225 [@option{--section-alignment=}@var{num}]
1226 [@option{--stack=}@var{size}]
1227 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1228 [@option{--compress-debug-sections}]
1229 [@option{--decompress-debug-sections}]
1230 [@option{--elf-stt-common=@var{val}}]
1231 [@option{--merge-notes}]
1232 [@option{--no-merge-notes}]
1233 [@option{--verilog-data-width=@var{val}}]
1234 [@option{-v}|@option{--verbose}]
1235 [@option{-V}|@option{--version}]
1236 [@option{--help}] [@option{--info}]
1237 @var{infile} [@var{outfile}]
1241 @c man begin DESCRIPTION objcopy
1242 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1243 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1244 read and write the object files. It can write the destination object
1245 file in a format different from that of the source object file. The
1246 exact behavior of @command{objcopy} is controlled by command-line options.
1247 Note that @command{objcopy} should be able to copy a fully linked file
1248 between any two formats. However, copying a relocatable object file
1249 between any two formats may not work as expected.
1251 @command{objcopy} creates temporary files to do its translations and
1252 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1253 translation work; it has access to all the formats described in @sc{bfd}
1254 and thus is able to recognize most formats without being told
1255 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1257 @command{objcopy} can be used to generate S-records by using an output
1258 target of @samp{srec} (e.g., use @samp{-O srec}).
1260 @command{objcopy} can be used to generate a raw binary file by using an
1261 output target of @samp{binary} (e.g., use @option{-O binary}). When
1262 @command{objcopy} generates a raw binary file, it will essentially produce
1263 a memory dump of the contents of the input object file. All symbols and
1264 relocation information will be discarded. The memory dump will start at
1265 the load address of the lowest section copied into the output file.
1267 When generating an S-record or a raw binary file, it may be helpful to
1268 use @option{-S} to remove sections containing debugging information. In
1269 some cases @option{-R} will be useful to remove sections which contain
1270 information that is not needed by the binary file.
1272 Note---@command{objcopy} is not able to change the endianness of its input
1273 files. If the input format has an endianness (some formats do not),
1274 @command{objcopy} can only copy the inputs into file formats that have the
1275 same endianness or which have no endianness (e.g., @samp{srec}).
1276 (However, see the @option{--reverse-bytes} option.)
1280 @c man begin OPTIONS objcopy
1284 @itemx @var{outfile}
1285 The input and output files, respectively.
1286 If you do not specify @var{outfile}, @command{objcopy} creates a
1287 temporary file and destructively renames the result with
1288 the name of @var{infile}.
1290 @item -I @var{bfdname}
1291 @itemx --input-target=@var{bfdname}
1292 Consider the source file's object format to be @var{bfdname}, rather than
1293 attempting to deduce it. @xref{Target Selection}, for more information.
1295 @item -O @var{bfdname}
1296 @itemx --output-target=@var{bfdname}
1297 Write the output file using the object format @var{bfdname}.
1298 @xref{Target Selection}, for more information.
1300 @item -F @var{bfdname}
1301 @itemx --target=@var{bfdname}
1302 Use @var{bfdname} as the object format for both the input and the output
1303 file; i.e., simply transfer data from source to destination with no
1304 translation. @xref{Target Selection}, for more information.
1306 @item -B @var{bfdarch}
1307 @itemx --binary-architecture=@var{bfdarch}
1308 Useful when transforming a architecture-less input file into an object file.
1309 In this case the output architecture can be set to @var{bfdarch}. This
1310 option will be ignored if the input file has a known @var{bfdarch}. You
1311 can access this binary data inside a program by referencing the special
1312 symbols that are created by the conversion process. These symbols are
1313 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1314 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1315 an object file and then access it in your code using these symbols.
1317 @item -j @var{sectionpattern}
1318 @itemx --only-section=@var{sectionpattern}
1319 Copy only the indicated sections from the input file to the output file.
1320 This option may be given more than once. Note that using this option
1321 inappropriately may make the output file unusable. Wildcard
1322 characters are accepted in @var{sectionpattern}.
1324 If the first character of @var{sectionpattern} is the exclamation
1325 point (!) then matching sections will not be copied, even if earlier
1326 use of @option{--only-section} on the same command line would
1327 otherwise copy it. For example:
1330 --only-section=.text.* --only-section=!.text.foo
1333 will copy all sectinos maching '.text.*' but not the section
1336 @item -R @var{sectionpattern}
1337 @itemx --remove-section=@var{sectionpattern}
1338 Remove any section matching @var{sectionpattern} from the output file.
1339 This option may be given more than once. Note that using this option
1340 inappropriately may make the output file unusable. Wildcard
1341 characters are accepted in @var{sectionpattern}. Using both the
1342 @option{-j} and @option{-R} options together results in undefined
1345 If the first character of @var{sectionpattern} is the exclamation
1346 point (!) then matching sections will not be removed even if an
1347 earlier use of @option{--remove-section} on the same command line
1348 would otherwise remove it. For example:
1351 --remove-section=.text.* --remove-section=!.text.foo
1354 will remove all sections matching the pattern '.text.*', but will not
1355 remove the section '.text.foo'.
1357 @item --remove-relocations=@var{sectionpattern}
1358 Remove non-dynamic relocations from the output file for any section
1359 matching @var{sectionpattern}. This option may be given more than
1360 once. Note that using this option inappropriately may make the output
1361 file unusable, and attempting to remove a dynamic relocation section
1362 such as @samp{.rela.plt} from an executable or shared library with
1363 @option{--remove-relocations=.plt} will not work. Wildcard characters
1364 are accepted in @var{sectionpattern}.
1368 --remove-relocations=.text.*
1371 will remove the relocations for all sections matching the pattern
1374 If the first character of @var{sectionpattern} is the exclamation
1375 point (!) then matching sections will not have their relocation
1376 removed even if an earlier use of @option{--remove-relocations} on the
1377 same command line would otherwise cause the relocations to be removed.
1381 --remove-relocations=.text.* --remove-relocations=!.text.foo
1384 will remove all relocations for sections matching the pattern
1385 '.text.*', but will not remove relocations for the section
1390 Do not copy relocation and symbol information from the source file.
1393 @itemx --strip-debug
1394 Do not copy debugging symbols or sections from the source file.
1396 @item --strip-unneeded
1397 Strip all symbols that are not needed for relocation processing.
1399 @item -K @var{symbolname}
1400 @itemx --keep-symbol=@var{symbolname}
1401 When stripping symbols, keep symbol @var{symbolname} even if it would
1402 normally be stripped. This option may be given more than once.
1404 @item -N @var{symbolname}
1405 @itemx --strip-symbol=@var{symbolname}
1406 Do not copy symbol @var{symbolname} from the source file. This option
1407 may be given more than once.
1409 @item --strip-unneeded-symbol=@var{symbolname}
1410 Do not copy symbol @var{symbolname} from the source file unless it is needed
1411 by a relocation. This option may be given more than once.
1413 @item -G @var{symbolname}
1414 @itemx --keep-global-symbol=@var{symbolname}
1415 Keep only symbol @var{symbolname} global. Make all other symbols local
1416 to the file, so that they are not visible externally. This option may
1417 be given more than once. Note: this option cannot be used in
1418 conjunction with the @option{--globalize-symbol} or
1419 @option{--globalize-symbols} options.
1421 @item --localize-hidden
1422 In an ELF object, mark all symbols that have hidden or internal visibility
1423 as local. This option applies on top of symbol-specific localization options
1424 such as @option{-L}.
1426 @item -L @var{symbolname}
1427 @itemx --localize-symbol=@var{symbolname}
1428 Convert a global or weak symbol called @var{symbolname} into a local
1429 symbol, so that it is not visible externally. This option may be
1430 given more than once. Note - unique symbols are not converted.
1432 @item -W @var{symbolname}
1433 @itemx --weaken-symbol=@var{symbolname}
1434 Make symbol @var{symbolname} weak. This option may be given more than once.
1436 @item --globalize-symbol=@var{symbolname}
1437 Give symbol @var{symbolname} global scoping so that it is visible
1438 outside of the file in which it is defined. This option may be given
1439 more than once. Note: this option cannot be used in conjunction with
1440 the @option{-G} or @option{--keep-global-symbol} options.
1444 Permit regular expressions in @var{symbolname}s used in other command
1445 line options. The question mark (?), asterisk (*), backslash (\) and
1446 square brackets ([]) operators can be used anywhere in the symbol
1447 name. If the first character of the symbol name is the exclamation
1448 point (!) then the sense of the switch is reversed for that symbol.
1455 would cause objcopy to weaken all symbols that start with ``fo''
1456 except for the symbol ``foo''.
1459 @itemx --discard-all
1460 Do not copy non-global symbols from the source file.
1461 @c FIXME any reason to prefer "non-global" to "local" here?
1464 @itemx --discard-locals
1465 Do not copy compiler-generated local symbols.
1466 (These usually start with @samp{L} or @samp{.}.)
1469 @itemx --byte=@var{byte}
1470 If interleaving has been enabled via the @option{--interleave} option
1471 then start the range of bytes to keep at the @var{byte}th byte.
1472 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1473 @var{breadth} is the value given by the @option{--interleave} option.
1475 @item -i [@var{breadth}]
1476 @itemx --interleave[=@var{breadth}]
1477 Only copy a range out of every @var{breadth} bytes. (Header data is
1478 not affected). Select which byte in the range begins the copy with
1479 the @option{--byte} option. Select the width of the range with the
1480 @option{--interleave-width} option.
1482 This option is useful for creating files to program @sc{rom}. It is
1483 typically used with an @code{srec} output target. Note that
1484 @command{objcopy} will complain if you do not specify the
1485 @option{--byte} option as well.
1487 The default interleave breadth is 4, so with @option{--byte} set to 0,
1488 @command{objcopy} would copy the first byte out of every four bytes
1489 from the input to the output.
1491 @item --interleave-width=@var{width}
1492 When used with the @option{--interleave} option, copy @var{width}
1493 bytes at a time. The start of the range of bytes to be copied is set
1494 by the @option{--byte} option, and the extent of the range is set with
1495 the @option{--interleave} option.
1497 The default value for this option is 1. The value of @var{width} plus
1498 the @var{byte} value set by the @option{--byte} option must not exceed
1499 the interleave breadth set by the @option{--interleave} option.
1501 This option can be used to create images for two 16-bit flashes interleaved
1502 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1503 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1504 commands. If the input was '12345678' then the outputs would be
1505 '1256' and '3478' respectively.
1508 @itemx --preserve-dates
1509 Set the access and modification dates of the output file to be the same
1510 as those of the input file.
1513 @itemx --enable-deterministic-archives
1514 @cindex deterministic archives
1515 @kindex --enable-deterministic-archives
1516 Operate in @emph{deterministic} mode. When copying archive members
1517 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1518 and use consistent file modes for all files.
1520 If @file{binutils} was configured with
1521 @option{--enable-deterministic-archives}, then this mode is on by default.
1522 It can be disabled with the @samp{-U} option, below.
1525 @itemx --disable-deterministic-archives
1526 @cindex deterministic archives
1527 @kindex --enable-deterministic-archives
1528 Do @emph{not} operate in @emph{deterministic} mode. This is the
1529 inverse of the @option{-D} option, above: when copying archive members
1530 and writing the archive index, use their actual UID, GID, timestamp,
1531 and file mode values.
1533 This is the default unless @file{binutils} was configured with
1534 @option{--enable-deterministic-archives}.
1537 Convert debugging information, if possible. This is not the default
1538 because only certain debugging formats are supported, and the
1539 conversion process can be time consuming.
1541 @item --gap-fill @var{val}
1542 Fill gaps between sections with @var{val}. This operation applies to
1543 the @emph{load address} (LMA) of the sections. It is done by increasing
1544 the size of the section with the lower address, and filling in the extra
1545 space created with @var{val}.
1547 @item --pad-to @var{address}
1548 Pad the output file up to the load address @var{address}. This is
1549 done by increasing the size of the last section. The extra space is
1550 filled in with the value specified by @option{--gap-fill} (default zero).
1552 @item --set-start @var{val}
1553 Set the start address of the new file to @var{val}. Not all object file
1554 formats support setting the start address.
1556 @item --change-start @var{incr}
1557 @itemx --adjust-start @var{incr}
1558 @cindex changing start address
1559 Change the start address by adding @var{incr}. Not all object file
1560 formats support setting the start address.
1562 @item --change-addresses @var{incr}
1563 @itemx --adjust-vma @var{incr}
1564 @cindex changing object addresses
1565 Change the VMA and LMA addresses of all sections, as well as the start
1566 address, by adding @var{incr}. Some object file formats do not permit
1567 section addresses to be changed arbitrarily. Note that this does not
1568 relocate the sections; if the program expects sections to be loaded at a
1569 certain address, and this option is used to change the sections such
1570 that they are loaded at a different address, the program may fail.
1572 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1573 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1574 @cindex changing section address
1575 Set or change both the VMA address and the LMA address of any section
1576 matching @var{sectionpattern}. If @samp{=} is used, the section
1577 address is set to @var{val}. Otherwise, @var{val} is added to or
1578 subtracted from the section address. See the comments under
1579 @option{--change-addresses}, above. If @var{sectionpattern} does not
1580 match any sections in the input file, a warning will be issued, unless
1581 @option{--no-change-warnings} is used.
1583 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1584 @cindex changing section LMA
1585 Set or change the LMA address of any sections matching
1586 @var{sectionpattern}. The LMA address is the address where the
1587 section will be loaded into memory at program load time. Normally
1588 this is the same as the VMA address, which is the address of the
1589 section at program run time, but on some systems, especially those
1590 where a program is held in ROM, the two can be different. If @samp{=}
1591 is used, the section address is set to @var{val}. Otherwise,
1592 @var{val} is added to or subtracted from the section address. See the
1593 comments under @option{--change-addresses}, above. If
1594 @var{sectionpattern} does not match any sections in the input file, a
1595 warning will be issued, unless @option{--no-change-warnings} is used.
1597 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1598 @cindex changing section VMA
1599 Set or change the VMA address of any section matching
1600 @var{sectionpattern}. The VMA address is the address where the
1601 section will be located once the program has started executing.
1602 Normally this is the same as the LMA address, which is the address
1603 where the section will be loaded into memory, but on some systems,
1604 especially those where a program is held in ROM, the two can be
1605 different. If @samp{=} is used, the section address is set to
1606 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1607 section address. See the comments under @option{--change-addresses},
1608 above. If @var{sectionpattern} does not match any sections in the
1609 input file, a warning will be issued, unless
1610 @option{--no-change-warnings} is used.
1612 @item --change-warnings
1613 @itemx --adjust-warnings
1614 If @option{--change-section-address} or @option{--change-section-lma} or
1615 @option{--change-section-vma} is used, and the section pattern does not
1616 match any sections, issue a warning. This is the default.
1618 @item --no-change-warnings
1619 @itemx --no-adjust-warnings
1620 Do not issue a warning if @option{--change-section-address} or
1621 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1622 if the section pattern does not match any sections.
1624 @item --set-section-flags @var{sectionpattern}=@var{flags}
1625 Set the flags for any sections matching @var{sectionpattern}. The
1626 @var{flags} argument is a comma separated string of flag names. The
1627 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1628 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1629 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1630 for a section which does not have contents, but it is not meaningful
1631 to clear the @samp{contents} flag of a section which does have
1632 contents--just remove the section instead. Not all flags are
1633 meaningful for all object file formats.
1635 @item --set-section-alignment @var{sectionpattern}=@var{align}
1636 Set the alignment for any sections matching @var{sectionpattern}.
1637 @var{align} specifies the alignment in bytes and must be a power of
1638 two, i.e. 1, 2, 4, 8@dots{}.
1640 @item --add-section @var{sectionname}=@var{filename}
1641 Add a new section named @var{sectionname} while copying the file. The
1642 contents of the new section are taken from the file @var{filename}. The
1643 size of the section will be the size of the file. This option only
1644 works on file formats which can support sections with arbitrary names.
1645 Note - it may be necessary to use the @option{--set-section-flags}
1646 option to set the attributes of the newly created section.
1648 @item --dump-section @var{sectionname}=@var{filename}
1649 Place the contents of section named @var{sectionname} into the file
1650 @var{filename}, overwriting any contents that may have been there
1651 previously. This option is the inverse of @option{--add-section}.
1652 This option is similar to the @option{--only-section} option except
1653 that it does not create a formatted file, it just dumps the contents
1654 as raw binary data, without applying any relocations. The option can
1655 be specified more than once.
1657 @item --update-section @var{sectionname}=@var{filename}
1658 Replace the existing contents of a section named @var{sectionname}
1659 with the contents of file @var{filename}. The size of the section
1660 will be adjusted to the size of the file. The section flags for
1661 @var{sectionname} will be unchanged. For ELF format files the section
1662 to segment mapping will also remain unchanged, something which is not
1663 possible using @option{--remove-section} followed by
1664 @option{--add-section}. The option can be specified more than once.
1666 Note - it is possible to use @option{--rename-section} and
1667 @option{--update-section} to both update and rename a section from one
1668 command line. In this case, pass the original section name to
1669 @option{--update-section}, and the original and new section names to
1670 @option{--rename-section}.
1672 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1673 Add a new symbol named @var{name} while copying the file. This option may be
1674 specified multiple times. If the @var{section} is given, the symbol will be
1675 associated with and relative to that section, otherwise it will be an ABS
1676 symbol. Specifying an undefined section will result in a fatal error. There
1677 is no check for the value, it will be taken as specified. Symbol flags can
1678 be specified and not all flags will be meaningful for all object file
1679 formats. By default, the symbol will be global. The special flag
1680 'before=@var{othersym}' will insert the new symbol in front of the specified
1681 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1682 symbol table in the order they appear.
1684 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1685 Rename a section from @var{oldname} to @var{newname}, optionally
1686 changing the section's flags to @var{flags} in the process. This has
1687 the advantage over using a linker script to perform the rename in that
1688 the output stays as an object file and does not become a linked
1691 This option is particularly helpful when the input format is binary,
1692 since this will always create a section called .data. If for example,
1693 you wanted instead to create a section called .rodata containing binary
1694 data you could use the following command line to achieve it:
1697 objcopy -I binary -O <output_format> -B <architecture> \
1698 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1699 <input_binary_file> <output_object_file>
1702 @item --long-section-names @{enable,disable,keep@}
1703 Controls the handling of long section names when processing @code{COFF}
1704 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1705 is to preserve long section names if any are present in the input file.
1706 The @samp{enable} and @samp{disable} options forcibly enable or disable
1707 the use of long section names in the output object; when @samp{disable}
1708 is in effect, any long section names in the input object will be truncated.
1709 The @samp{enable} option will only emit long section names if any are
1710 present in the inputs; this is mostly the same as @samp{keep}, but it
1711 is left undefined whether the @samp{enable} option might force the
1712 creation of an empty string table in the output file.
1714 @item --change-leading-char
1715 Some object file formats use special characters at the start of
1716 symbols. The most common such character is underscore, which compilers
1717 often add before every symbol. This option tells @command{objcopy} to
1718 change the leading character of every symbol when it converts between
1719 object file formats. If the object file formats use the same leading
1720 character, this option has no effect. Otherwise, it will add a
1721 character, or remove a character, or change a character, as
1724 @item --remove-leading-char
1725 If the first character of a global symbol is a special symbol leading
1726 character used by the object file format, remove the character. The
1727 most common symbol leading character is underscore. This option will
1728 remove a leading underscore from all global symbols. This can be useful
1729 if you want to link together objects of different file formats with
1730 different conventions for symbol names. This is different from
1731 @option{--change-leading-char} because it always changes the symbol name
1732 when appropriate, regardless of the object file format of the output
1735 @item --reverse-bytes=@var{num}
1736 Reverse the bytes in a section with output contents. A section length must
1737 be evenly divisible by the value given in order for the swap to be able to
1738 take place. Reversing takes place before the interleaving is performed.
1740 This option is used typically in generating ROM images for problematic
1741 target systems. For example, on some target boards, the 32-bit words
1742 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1743 regardless of the CPU byte order. Depending on the programming model, the
1744 endianness of the ROM may need to be modified.
1746 Consider a simple file with a section containing the following eight
1747 bytes: @code{12345678}.
1749 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1750 output file would be ordered @code{21436587}.
1752 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1753 output file would be ordered @code{43218765}.
1755 By using @samp{--reverse-bytes=2} for the above example, followed by
1756 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1757 output file would be ordered @code{34127856}.
1759 @item --srec-len=@var{ival}
1760 Meaningful only for srec output. Set the maximum length of the Srecords
1761 being produced to @var{ival}. This length covers both address, data and
1764 @item --srec-forceS3
1765 Meaningful only for srec output. Avoid generation of S1/S2 records,
1766 creating S3-only record format.
1768 @item --redefine-sym @var{old}=@var{new}
1769 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1770 when one is trying link two things together for which you have no
1771 source, and there are name collisions.
1773 @item --redefine-syms=@var{filename}
1774 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1775 listed in the file @var{filename}. @var{filename} is simply a flat file,
1776 with one symbol pair per line. Line comments may be introduced by the hash
1777 character. This option may be given more than once.
1780 Change all global symbols in the file to be weak. This can be useful
1781 when building an object which will be linked against other objects using
1782 the @option{-R} option to the linker. This option is only effective when
1783 using an object file format which supports weak symbols.
1785 @item --keep-symbols=@var{filename}
1786 Apply @option{--keep-symbol} option to each symbol listed in the file
1787 @var{filename}. @var{filename} is simply a flat file, with one symbol
1788 name per line. Line comments may be introduced by the hash character.
1789 This option may be given more than once.
1791 @item --strip-symbols=@var{filename}
1792 Apply @option{--strip-symbol} option to each symbol listed in the file
1793 @var{filename}. @var{filename} is simply a flat file, with one symbol
1794 name per line. Line comments may be introduced by the hash character.
1795 This option may be given more than once.
1797 @item --strip-unneeded-symbols=@var{filename}
1798 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1799 the file @var{filename}. @var{filename} is simply a flat file, with one
1800 symbol name per line. Line comments may be introduced by the hash
1801 character. This option may be given more than once.
1803 @item --keep-global-symbols=@var{filename}
1804 Apply @option{--keep-global-symbol} option to each symbol listed in the
1805 file @var{filename}. @var{filename} is simply a flat file, with one
1806 symbol name per line. Line comments may be introduced by the hash
1807 character. This option may be given more than once.
1809 @item --localize-symbols=@var{filename}
1810 Apply @option{--localize-symbol} option to each symbol listed in the file
1811 @var{filename}. @var{filename} is simply a flat file, with one symbol
1812 name per line. Line comments may be introduced by the hash character.
1813 This option may be given more than once.
1815 @item --globalize-symbols=@var{filename}
1816 Apply @option{--globalize-symbol} option to each symbol listed in the file
1817 @var{filename}. @var{filename} is simply a flat file, with one symbol
1818 name per line. Line comments may be introduced by the hash character.
1819 This option may be given more than once. Note: this option cannot be
1820 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1823 @item --weaken-symbols=@var{filename}
1824 Apply @option{--weaken-symbol} option to each symbol listed in the file
1825 @var{filename}. @var{filename} is simply a flat file, with one symbol
1826 name per line. Line comments may be introduced by the hash character.
1827 This option may be given more than once.
1829 @item --alt-machine-code=@var{index}
1830 If the output architecture has alternate machine codes, use the
1831 @var{index}th code instead of the default one. This is useful in case
1832 a machine is assigned an official code and the tool-chain adopts the
1833 new code, but other applications still depend on the original code
1834 being used. For ELF based architectures if the @var{index}
1835 alternative does not exist then the value is treated as an absolute
1836 number to be stored in the e_machine field of the ELF header.
1838 @item --writable-text
1839 Mark the output text as writable. This option isn't meaningful for all
1840 object file formats.
1842 @item --readonly-text
1843 Make the output text write protected. This option isn't meaningful for all
1844 object file formats.
1847 Mark the output file as demand paged. This option isn't meaningful for all
1848 object file formats.
1851 Mark the output file as impure. This option isn't meaningful for all
1852 object file formats.
1854 @item --prefix-symbols=@var{string}
1855 Prefix all symbols in the output file with @var{string}.
1857 @item --prefix-sections=@var{string}
1858 Prefix all section names in the output file with @var{string}.
1860 @item --prefix-alloc-sections=@var{string}
1861 Prefix all the names of all allocated sections in the output file with
1864 @item --add-gnu-debuglink=@var{path-to-file}
1865 Creates a .gnu_debuglink section which contains a reference to
1866 @var{path-to-file} and adds it to the output file. Note: the file at
1867 @var{path-to-file} must exist. Part of the process of adding the
1868 .gnu_debuglink section involves embedding a checksum of the contents
1869 of the debug info file into the section.
1871 If the debug info file is built in one location but it is going to be
1872 installed at a later time into a different location then do not use
1873 the path to the installed location. The @option{--add-gnu-debuglink}
1874 option will fail because the installed file does not exist yet.
1875 Instead put the debug info file in the current directory and use the
1876 @option{--add-gnu-debuglink} option without any directory components,
1880 objcopy --add-gnu-debuglink=foo.debug
1883 At debug time the debugger will attempt to look for the separate debug
1884 info file in a set of known locations. The exact set of these
1885 locations varies depending upon the distribution being used, but it
1890 @item * The same directory as the executable.
1892 @item * A sub-directory of the directory containing the executable
1895 @item * A global debug directory such as /usr/lib/debug.
1898 As long as the debug info file has been installed into one of these
1899 locations before the debugger is run everything should work
1902 @item --keep-file-symbols
1903 When stripping a file, perhaps with @option{--strip-debug} or
1904 @option{--strip-unneeded}, retain any symbols specifying source file names,
1905 which would otherwise get stripped.
1907 @item --only-keep-debug
1908 Strip a file, removing contents of any sections that would not be
1909 stripped by @option{--strip-debug} and leaving the debugging sections
1910 intact. In ELF files, this preserves all note sections in the output.
1912 Note - the section headers of the stripped sections are preserved,
1913 including their sizes, but the contents of the section are discarded.
1914 The section headers are preserved so that other tools can match up the
1915 debuginfo file with the real executable, even if that executable has
1916 been relocated to a different address space.
1918 The intention is that this option will be used in conjunction with
1919 @option{--add-gnu-debuglink} to create a two part executable. One a
1920 stripped binary which will occupy less space in RAM and in a
1921 distribution and the second a debugging information file which is only
1922 needed if debugging abilities are required. The suggested procedure
1923 to create these files is as follows:
1926 @item Link the executable as normal. Assuming that it is called
1928 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1929 create a file containing the debugging info.
1930 @item Run @code{objcopy --strip-debug foo} to create a
1931 stripped executable.
1932 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1933 to add a link to the debugging info into the stripped executable.
1936 Note---the choice of @code{.dbg} as an extension for the debug info
1937 file is arbitrary. Also the @code{--only-keep-debug} step is
1938 optional. You could instead do this:
1941 @item Link the executable as normal.
1942 @item Copy @code{foo} to @code{foo.full}
1943 @item Run @code{objcopy --strip-debug foo}
1944 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1947 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1948 full executable. It does not have to be a file created by the
1949 @option{--only-keep-debug} switch.
1951 Note---this switch is only intended for use on fully linked files. It
1952 does not make sense to use it on object files where the debugging
1953 information may be incomplete. Besides the gnu_debuglink feature
1954 currently only supports the presence of one filename containing
1955 debugging information, not multiple filenames on a one-per-object-file
1959 Remove the contents of all DWARF .dwo sections, leaving the
1960 remaining debugging sections and all symbols intact.
1961 This option is intended for use by the compiler as part of
1962 the @option{-gsplit-dwarf} option, which splits debug information
1963 between the .o file and a separate .dwo file. The compiler
1964 generates all debug information in the same file, then uses
1965 the @option{--extract-dwo} option to copy the .dwo sections to
1966 the .dwo file, then the @option{--strip-dwo} option to remove
1967 those sections from the original .o file.
1970 Extract the contents of all DWARF .dwo sections. See the
1971 @option{--strip-dwo} option for more information.
1973 @item --file-alignment @var{num}
1974 Specify the file alignment. Sections in the file will always begin at
1975 file offsets which are multiples of this number. This defaults to
1977 [This option is specific to PE targets.]
1979 @item --heap @var{reserve}
1980 @itemx --heap @var{reserve},@var{commit}
1981 Specify the number of bytes of memory to reserve (and optionally commit)
1982 to be used as heap for this program.
1983 [This option is specific to PE targets.]
1985 @item --image-base @var{value}
1986 Use @var{value} as the base address of your program or dll. This is
1987 the lowest memory location that will be used when your program or dll
1988 is loaded. To reduce the need to relocate and improve performance of
1989 your dlls, each should have a unique base address and not overlap any
1990 other dlls. The default is 0x400000 for executables, and 0x10000000
1992 [This option is specific to PE targets.]
1994 @item --section-alignment @var{num}
1995 Sets the section alignment field in the PE header. Sections in memory
1996 will always begin at addresses which are a multiple of this number.
1998 [This option is specific to PE targets.]
2000 @item --stack @var{reserve}
2001 @itemx --stack @var{reserve},@var{commit}
2002 Specify the number of bytes of memory to reserve (and optionally commit)
2003 to be used as stack for this program.
2004 [This option is specific to PE targets.]
2006 @item --subsystem @var{which}
2007 @itemx --subsystem @var{which}:@var{major}
2008 @itemx --subsystem @var{which}:@var{major}.@var{minor}
2009 Specifies the subsystem under which your program will execute. The
2010 legal values for @var{which} are @code{native}, @code{windows},
2011 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
2012 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
2013 the subsystem version also. Numeric values are also accepted for
2015 [This option is specific to PE targets.]
2017 @item --extract-symbol
2018 Keep the file's section flags and symbols but remove all section data.
2019 Specifically, the option:
2022 @item removes the contents of all sections;
2023 @item sets the size of every section to zero; and
2024 @item sets the file's start address to zero.
2027 This option is used to build a @file{.sym} file for a VxWorks kernel.
2028 It can also be a useful way of reducing the size of a @option{--just-symbols}
2031 @item --compress-debug-sections
2032 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2033 ELF ABI. Note - if compression would actually make a section
2034 @emph{larger}, then it is not compressed.
2036 @item --compress-debug-sections=none
2037 @itemx --compress-debug-sections=zlib
2038 @itemx --compress-debug-sections=zlib-gnu
2039 @itemx --compress-debug-sections=zlib-gabi
2040 For ELF files, these options control how DWARF debug sections are
2041 compressed. @option{--compress-debug-sections=none} is equivalent
2042 to @option{--decompress-debug-sections}.
2043 @option{--compress-debug-sections=zlib} and
2044 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2045 @option{--compress-debug-sections}.
2046 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
2047 sections using zlib. The debug sections are renamed to begin with
2048 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
2049 actually make a section @emph{larger}, then it is not compressed nor
2052 @item --decompress-debug-sections
2053 Decompress DWARF debug sections using zlib. The original section
2054 names of the compressed sections are restored.
2056 @item --elf-stt-common=yes
2057 @itemx --elf-stt-common=no
2058 For ELF files, these options control whether common symbols should be
2059 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2060 @option{--elf-stt-common=yes} converts common symbol type to
2061 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2062 type to @code{STT_OBJECT}.
2065 @itemx --no-merge-notes
2066 For ELF files, attempt (or do not attempt) to reduce the size of any
2067 SHT_NOTE type sections by removing duplicate notes.
2071 Show the version number of @command{objcopy}.
2073 @item --verilog-data-width=@var{bytes}
2074 For Verilog output, this options controls the number of bytes
2075 converted for each output data element. The input target controls the
2076 endianness of the conversion.
2080 Verbose output: list all object files modified. In the case of
2081 archives, @samp{objcopy -V} lists all members of the archive.
2084 Show a summary of the options to @command{objcopy}.
2087 Display a list showing all architectures and object formats available.
2093 @c man begin SEEALSO objcopy
2094 ld(1), objdump(1), and the Info entries for @file{binutils}.
2101 @cindex object file information
2104 @c man title objdump display information from object files
2107 @c man begin SYNOPSIS objdump
2108 objdump [@option{-a}|@option{--archive-headers}]
2109 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2110 [@option{-C}|@option{--demangle}[=@var{style}] ]
2111 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2112 [@option{-D}|@option{--disassemble-all}]
2113 [@option{-z}|@option{--disassemble-zeroes}]
2114 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2115 [@option{-f}|@option{--file-headers}]
2116 [@option{-F}|@option{--file-offsets}]
2117 [@option{--file-start-context}]
2118 [@option{-g}|@option{--debugging}]
2119 [@option{-e}|@option{--debugging-tags}]
2120 [@option{-h}|@option{--section-headers}|@option{--headers}]
2121 [@option{-i}|@option{--info}]
2122 [@option{-j} @var{section}|@option{--section=}@var{section}]
2123 [@option{-l}|@option{--line-numbers}]
2124 [@option{-S}|@option{--source}]
2125 [@option{--source-comment}[=@var{text}]]
2126 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2127 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2128 [@option{-p}|@option{--private-headers}]
2129 [@option{-P} @var{options}|@option{--private=}@var{options}]
2130 [@option{-r}|@option{--reloc}]
2131 [@option{-R}|@option{--dynamic-reloc}]
2132 [@option{-s}|@option{--full-contents}]
2133 [@option{-W[lLiaprmfFsoRtUuTgAckK]}|
2134 @option{--dwarf}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]]
2135 [@option{--ctf=}@var{section}]
2136 [@option{-G}|@option{--stabs}]
2137 [@option{-t}|@option{--syms}]
2138 [@option{-T}|@option{--dynamic-syms}]
2139 [@option{-x}|@option{--all-headers}]
2140 [@option{-w}|@option{--wide}]
2141 [@option{--start-address=}@var{address}]
2142 [@option{--stop-address=}@var{address}]
2143 [@option{--prefix-addresses}]
2144 [@option{--[no-]show-raw-insn}]
2145 [@option{--adjust-vma=}@var{offset}]
2146 [@option{--dwarf-depth=@var{n}}]
2147 [@option{--dwarf-start=@var{n}}]
2148 [@option{--ctf-parent=}@var{section}]
2149 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2150 [@option{--special-syms}]
2151 [@option{--prefix=}@var{prefix}]
2152 [@option{--prefix-strip=}@var{level}]
2153 [@option{--insn-width=}@var{width}]
2154 [@option{-V}|@option{--version}]
2155 [@option{-H}|@option{--help}]
2156 @var{objfile}@dots{}
2160 @c man begin DESCRIPTION objdump
2162 @command{objdump} displays information about one or more object files.
2163 The options control what particular information to display. This
2164 information is mostly useful to programmers who are working on the
2165 compilation tools, as opposed to programmers who just want their
2166 program to compile and work.
2168 @var{objfile}@dots{} are the object files to be examined. When you
2169 specify archives, @command{objdump} shows information on each of the member
2174 @c man begin OPTIONS objdump
2176 The long and short forms of options, shown here as alternatives, are
2177 equivalent. At least one option from the list
2178 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2182 @itemx --archive-header
2183 @cindex archive headers
2184 If any of the @var{objfile} files are archives, display the archive
2185 header information (in a format similar to @samp{ls -l}). Besides the
2186 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2187 the object file format of each archive member.
2189 @item --adjust-vma=@var{offset}
2190 @cindex section addresses in objdump
2191 @cindex VMA in objdump
2192 When dumping information, first add @var{offset} to all the section
2193 addresses. This is useful if the section addresses do not correspond to
2194 the symbol table, which can happen when putting sections at particular
2195 addresses when using a format which can not represent section addresses,
2198 @item -b @var{bfdname}
2199 @itemx --target=@var{bfdname}
2200 @cindex object code format
2201 Specify that the object-code format for the object files is
2202 @var{bfdname}. This option may not be necessary; @var{objdump} can
2203 automatically recognize many formats.
2207 objdump -b oasys -m vax -h fu.o
2210 displays summary information from the section headers (@option{-h}) of
2211 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2212 file in the format produced by Oasys compilers. You can list the
2213 formats available with the @option{-i} option.
2214 @xref{Target Selection}, for more information.
2217 @itemx --demangle[=@var{style}]
2218 @cindex demangling in objdump
2219 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2220 Besides removing any initial underscore prepended by the system, this
2221 makes C++ function names readable. Different compilers have different
2222 mangling styles. The optional demangling style argument can be used to
2223 choose an appropriate demangling style for your compiler. @xref{c++filt},
2224 for more information on demangling.
2226 @item --recurse-limit
2227 @itemx --no-recurse-limit
2228 @itemx --recursion-limit
2229 @itemx --no-recursion-limit
2230 Enables or disables a limit on the amount of recursion performed
2231 whilst demangling strings. Since the name mangling formats allow for
2232 an inifinite level of recursion it is possible to create strings whose
2233 decoding will exhaust the amount of stack space available on the host
2234 machine, triggering a memory fault. The limit tries to prevent this
2235 from happening by restricting recursion to 2048 levels of nesting.
2237 The default is for this limit to be enabled, but disabling it may be
2238 necessary in order to demangle truly complicated names. Note however
2239 that if the recursion limit is disabled then stack exhaustion is
2240 possible and any bug reports about such an event will be rejected.
2244 Display debugging information. This attempts to parse STABS
2245 debugging format information stored in the file and print it out using
2246 a C like syntax. If no STABS debuging was found this option
2247 falls back on the @option{-W} option to print any DWARF information in
2251 @itemx --debugging-tags
2252 Like @option{-g}, but the information is generated in a format compatible
2256 @itemx --disassemble
2257 @itemx --disassemble=@var{symbol}
2258 @cindex disassembling object code
2259 @cindex machine instructions
2260 Display the assembler mnemonics for the machine instructions from the
2261 input file. This option only disassembles those sections which are
2262 expected to contain instructions. If the optional @var{symbol}
2263 argument is given, then display the assembler mnemonics starting at
2264 @var{symbol}. If @var{symbol} is a function name then disassembly
2265 will stop at the end of the function, otherwise it will stop when the
2266 next symbol is encountered. If there are no matches for @var{symbol}
2267 then nothing will be displayed.
2269 Note if the @option{--dwarf=follow-links} option has also been enabled
2270 then any symbol tables in linked debug info files will be read in and
2271 used when disassembling.
2274 @itemx --disassemble-all
2275 Like @option{-d}, but disassemble the contents of all sections, not just
2276 those expected to contain instructions.
2278 This option also has a subtle effect on the disassembly of
2279 instructions in code sections. When option @option{-d} is in effect
2280 objdump will assume that any symbols present in a code section occur
2281 on the boundary between instructions and it will refuse to disassemble
2282 across such a boundary. When option @option{-D} is in effect however
2283 this assumption is supressed. This means that it is possible for the
2284 output of @option{-d} and @option{-D} to differ if, for example, data
2285 is stored in code sections.
2287 If the target is an ARM architecture this switch also has the effect
2288 of forcing the disassembler to decode pieces of data found in code
2289 sections as if they were instructions.
2291 Note if the @option{--dwarf=follow-links} option has also been enabled
2292 then any symbol tables in linked debug info files will be read in and
2293 used when disassembling.
2295 @item --prefix-addresses
2296 When disassembling, print the complete address on each line. This is
2297 the older disassembly format.
2301 @itemx --endian=@{big|little@}
2303 @cindex disassembly endianness
2304 Specify the endianness of the object files. This only affects
2305 disassembly. This can be useful when disassembling a file format which
2306 does not describe endianness information, such as S-records.
2309 @itemx --file-headers
2310 @cindex object file header
2311 Display summary information from the overall header of
2312 each of the @var{objfile} files.
2315 @itemx --file-offsets
2316 @cindex object file offsets
2317 When disassembling sections, whenever a symbol is displayed, also
2318 display the file offset of the region of data that is about to be
2319 dumped. If zeroes are being skipped, then when disassembly resumes,
2320 tell the user how many zeroes were skipped and the file offset of the
2321 location from where the disassembly resumes. When dumping sections,
2322 display the file offset of the location from where the dump starts.
2324 @item --file-start-context
2325 @cindex source code context
2326 Specify that when displaying interlisted source code/disassembly
2327 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2328 context to the start of the file.
2331 @itemx --section-headers
2333 @cindex section headers
2334 Display summary information from the section headers of the
2337 File segments may be relocated to nonstandard addresses, for example by
2338 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2339 @command{ld}. However, some object file formats, such as a.out, do not
2340 store the starting address of the file segments. In those situations,
2341 although @command{ld} relocates the sections correctly, using @samp{objdump
2342 -h} to list the file section headers cannot show the correct addresses.
2343 Instead, it shows the usual addresses, which are implicit for the
2346 Note, in some cases it is possible for a section to have both the
2347 READONLY and the NOREAD attributes set. In such cases the NOREAD
2348 attribute takes precedence, but @command{objdump} will report both
2349 since the exact setting of the flag bits might be important.
2353 Print a summary of the options to @command{objdump} and exit.
2357 @cindex architectures available
2358 @cindex object formats available
2359 Display a list showing all architectures and object formats available
2360 for specification with @option{-b} or @option{-m}.
2363 @itemx --section=@var{name}
2364 @cindex section information
2365 Display information only for section @var{name}.
2368 @itemx --line-numbers
2369 @cindex source filenames for object files
2370 Label the display (using debugging information) with the filename and
2371 source line numbers corresponding to the object code or relocs shown.
2372 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2374 @item -m @var{machine}
2375 @itemx --architecture=@var{machine}
2376 @cindex architecture
2377 @cindex disassembly architecture
2378 Specify the architecture to use when disassembling object files. This
2379 can be useful when disassembling object files which do not describe
2380 architecture information, such as S-records. You can list the available
2381 architectures with the @option{-i} option.
2383 If the target is an ARM architecture then this switch has an
2384 additional effect. It restricts the disassembly to only those
2385 instructions supported by the architecture specified by @var{machine}.
2386 If it is necessary to use this switch because the input file does not
2387 contain any architecture information, but it is also desired to
2388 disassemble all the instructions use @option{-marm}.
2390 @item -M @var{options}
2391 @itemx --disassembler-options=@var{options}
2392 Pass target specific information to the disassembler. Only supported on
2393 some targets. If it is necessary to specify more than one
2394 disassembler option then multiple @option{-M} options can be used or
2395 can be placed together into a comma separated list.
2397 For ARC, @option{dsp} controls the printing of DSP instructions,
2398 @option{spfp} selects the printing of FPX single precision FP
2399 instructions, @option{dpfp} selects the printing of FPX double
2400 precision FP instructions, @option{quarkse_em} selects the printing of
2401 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2402 of double precision assist instructions, @option{fpus} selects the
2403 printing of FPU single precision FP instructions, while @option{fpud}
2404 selects the printing of FPU double precision FP instructions.
2405 Additionally, one can choose to have all the immediates printed in
2406 hexadecimal using @option{hex}. By default, the short immediates are
2407 printed using the decimal representation, while the long immediate
2408 values are printed as hexadecimal.
2410 @option{cpu=...} allows to enforce a particular ISA when disassembling
2411 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2412 This might be useful to select ARC EM or HS ISA, because architecture is same
2413 for those and disassembler relies on private ELF header data to decide if code
2414 is for EM or HS. This option might be specified multiple times - only the
2415 latest value will be used. Valid values are same as for the assembler
2416 @option{-mcpu=...} option.
2418 If the target is an ARM architecture then this switch can be used to
2419 select which register name set is used during disassembler. Specifying
2420 @option{-M reg-names-std} (the default) will select the register names as
2421 used in ARM's instruction set documentation, but with register 13 called
2422 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2423 @option{-M reg-names-apcs} will select the name set used by the ARM
2424 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2425 just use @samp{r} followed by the register number.
2427 There are also two variants on the APCS register naming scheme enabled
2428 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2429 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2430 with the normal register names or the special register names).
2432 This option can also be used for ARM architectures to force the
2433 disassembler to interpret all instructions as Thumb instructions by
2434 using the switch @option{--disassembler-options=force-thumb}. This can be
2435 useful when attempting to disassemble thumb code produced by other
2438 For AArch64 targets this switch can be used to set whether instructions are
2439 disassembled as the most general instruction using the @option{-M no-aliases}
2440 option or whether instruction notes should be generated as comments in the
2441 disasssembly using @option{-M notes}.
2443 For the x86, some of the options duplicate functions of the @option{-m}
2444 switch, but allow finer grained control. Multiple selections from the
2445 following may be specified as a comma separated string.
2450 Select disassembly for the given architecture.
2454 Select between intel syntax mode and AT&T syntax mode.
2458 Select between AMD64 ISA and Intel64 ISA.
2460 @item intel-mnemonic
2462 Select between intel mnemonic mode and AT&T mnemonic mode.
2463 Note: @code{intel-mnemonic} implies @code{intel} and
2464 @code{att-mnemonic} implies @code{att}.
2471 Specify the default address size and operand size. These five options
2472 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2473 appear later in the option string.
2476 When in AT&T mode, instructs the disassembler to print a mnemonic
2477 suffix even when the suffix could be inferred by the operands.
2480 For PowerPC, the @option{-M} argument @option{raw} selects
2481 disasssembly of hardware insns rather than aliases. For example, you
2482 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2483 rather than @code{li}. All of the @option{-m} arguments for
2484 @command{gas} that select a CPU are supported. These are:
2485 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2486 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2487 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2488 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2489 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2490 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2491 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2492 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2493 @option{power8}, @option{power9}, @option{ppc}, @option{ppc32},
2494 @option{ppc64}, @option{ppc64bridge}, @option{ppcps}, @option{pwr},
2495 @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2496 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2497 @option{pwrx}, @option{titan}, and @option{vle}.
2498 @option{32} and @option{64} modify the default or a prior CPU
2499 selection, disabling and enabling 64-bit insns respectively. In
2500 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2501 and @option{spe} add capabilities to a previous @emph{or later} CPU
2502 selection. @option{any} will disassemble any opcode known to
2503 binutils, but in cases where an opcode has two different meanings or
2504 different arguments, you may not see the disassembly you expect.
2505 If you disassemble without giving a CPU selection, a default will be
2506 chosen from information gleaned by BFD from the object files headers,
2507 but the result again may not be as you expect.
2509 For MIPS, this option controls the printing of instruction mnemonic
2510 names and register names in disassembled instructions. Multiple
2511 selections from the following may be specified as a comma separated
2512 string, and invalid options are ignored:
2516 Print the 'raw' instruction mnemonic instead of some pseudo
2517 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2518 'sll' instead of 'nop', etc.
2521 Disassemble MSA instructions.
2524 Disassemble the virtualization ASE instructions.
2527 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2529 @item gpr-names=@var{ABI}
2530 Print GPR (general-purpose register) names as appropriate
2531 for the specified ABI. By default, GPR names are selected according to
2532 the ABI of the binary being disassembled.
2534 @item fpr-names=@var{ABI}
2535 Print FPR (floating-point register) names as
2536 appropriate for the specified ABI. By default, FPR numbers are printed
2539 @item cp0-names=@var{ARCH}
2540 Print CP0 (system control coprocessor; coprocessor 0) register names
2541 as appropriate for the CPU or architecture specified by
2542 @var{ARCH}. By default, CP0 register names are selected according to
2543 the architecture and CPU of the binary being disassembled.
2545 @item hwr-names=@var{ARCH}
2546 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2547 as appropriate for the CPU or architecture specified by
2548 @var{ARCH}. By default, HWR names are selected according to
2549 the architecture and CPU of the binary being disassembled.
2551 @item reg-names=@var{ABI}
2552 Print GPR and FPR names as appropriate for the selected ABI.
2554 @item reg-names=@var{ARCH}
2555 Print CPU-specific register names (CP0 register and HWR names)
2556 as appropriate for the selected CPU or architecture.
2559 For any of the options listed above, @var{ABI} or
2560 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2561 rather than names, for the selected types of registers.
2562 You can list the available values of @var{ABI} and @var{ARCH} using
2563 the @option{--help} option.
2565 For VAX, you can specify function entry addresses with @option{-M
2566 entry:0xf00ba}. You can use this multiple times to properly
2567 disassemble VAX binary files that don't contain symbol tables (like
2568 ROM dumps). In these cases, the function entry mask would otherwise
2569 be decoded as VAX instructions, which would probably lead the rest
2570 of the function being wrongly disassembled.
2573 @itemx --private-headers
2574 Print information that is specific to the object file format. The exact
2575 information printed depends upon the object file format. For some
2576 object file formats, no additional information is printed.
2578 @item -P @var{options}
2579 @itemx --private=@var{options}
2580 Print information that is specific to the object file format. The
2581 argument @var{options} is a comma separated list that depends on the
2582 format (the lists of options is displayed with the help).
2584 For XCOFF, the available options are:
2600 Not all object formats support this option. In particular the ELF
2601 format does not use it.
2605 @cindex relocation entries, in object file
2606 Print the relocation entries of the file. If used with @option{-d} or
2607 @option{-D}, the relocations are printed interspersed with the
2611 @itemx --dynamic-reloc
2612 @cindex dynamic relocation entries, in object file
2613 Print the dynamic relocation entries of the file. This is only
2614 meaningful for dynamic objects, such as certain types of shared
2615 libraries. As for @option{-r}, if used with @option{-d} or
2616 @option{-D}, the relocations are printed interspersed with the
2620 @itemx --full-contents
2621 @cindex sections, full contents
2622 @cindex object file sections
2623 Display the full contents of any sections requested. By default all
2624 non-empty sections are displayed.
2628 @cindex source disassembly
2629 @cindex disassembly, with source
2630 Display source code intermixed with disassembly, if possible. Implies
2633 @item --source-comment[=@var{txt}]
2634 @cindex source disassembly
2635 @cindex disassembly, with source
2636 Like the @option{-S} option, but all source code lines are displayed
2637 with a prefix of @var{txt}. Typically @var{txt} will be a comment
2638 string which can be used to distinguish the assembler code from the
2639 source code. If @var{txt} is not provided then a default string of
2640 @var{``# ``} (hash followed by a space), will be used.
2642 @item --prefix=@var{prefix}
2643 @cindex Add prefix to absolute paths
2644 Specify @var{prefix} to add to the absolute paths when used with
2647 @item --prefix-strip=@var{level}
2648 @cindex Strip absolute paths
2649 Indicate how many initial directory names to strip off the hardwired
2650 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2652 @item --show-raw-insn
2653 When disassembling instructions, print the instruction in hex as well as
2654 in symbolic form. This is the default except when
2655 @option{--prefix-addresses} is used.
2657 @item --no-show-raw-insn
2658 When disassembling instructions, do not print the instruction bytes.
2659 This is the default when @option{--prefix-addresses} is used.
2661 @item --insn-width=@var{width}
2662 @cindex Instruction width
2663 Display @var{width} bytes on a single line when disassembling
2666 @item -W[lLiaprmfFsoRtUuTgAckK]
2667 @itemx --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
2668 @include debug.options.texi
2671 Enable additional checks for consistency of Dwarf information.
2673 @include ctf.options.texi
2679 @cindex debug symbols
2680 @cindex ELF object file format
2681 Display the full contents of any sections requested. Display the
2682 contents of the .stab and .stab.index and .stab.excl sections from an
2683 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2684 @code{.stab} debugging symbol-table entries are carried in an ELF
2685 section. In most other file formats, debugging symbol-table entries are
2686 interleaved with linkage symbols, and are visible in the @option{--syms}
2689 @item --start-address=@var{address}
2690 @cindex start-address
2691 Start displaying data at the specified address. This affects the output
2692 of the @option{-d}, @option{-r} and @option{-s} options.
2694 @item --stop-address=@var{address}
2695 @cindex stop-address
2696 Stop displaying data at the specified address. This affects the output
2697 of the @option{-d}, @option{-r} and @option{-s} options.
2701 @cindex symbol table entries, printing
2702 Print the symbol table entries of the file.
2703 This is similar to the information provided by the @samp{nm} program,
2704 although the display format is different. The format of the output
2705 depends upon the format of the file being dumped, but there are two main
2706 types. One looks like this:
2709 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2710 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2713 where the number inside the square brackets is the number of the entry
2714 in the symbol table, the @var{sec} number is the section number, the
2715 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2716 symbol's type, the @var{scl} number is the symbol's storage class and
2717 the @var{nx} value is the number of auxilary entries associated with
2718 the symbol. The last two fields are the symbol's value and its name.
2720 The other common output format, usually seen with ELF based files,
2724 00000000 l d .bss 00000000 .bss
2725 00000000 g .text 00000000 fred
2728 Here the first number is the symbol's value (sometimes refered to as
2729 its address). The next field is actually a set of characters and
2730 spaces indicating the flag bits that are set on the symbol. These
2731 characters are described below. Next is the section with which the
2732 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2733 not connected with any section), or @emph{*UND*} if the section is
2734 referenced in the file being dumped, but not defined there.
2736 After the section name comes another field, a number, which for common
2737 symbols is the alignment and for other symbol is the size. Finally
2738 the symbol's name is displayed.
2740 The flag characters are divided into 7 groups as follows:
2746 The symbol is a local (l), global (g), unique global (u), neither
2747 global nor local (a space) or both global and local (!). A
2748 symbol can be neither local or global for a variety of reasons, e.g.,
2749 because it is used for debugging, but it is probably an indication of
2750 a bug if it is ever both local and global. Unique global symbols are
2751 a GNU extension to the standard set of ELF symbol bindings. For such
2752 a symbol the dynamic linker will make sure that in the entire process
2753 there is just one symbol with this name and type in use.
2756 The symbol is weak (w) or strong (a space).
2759 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2762 The symbol is a warning (W) or a normal symbol (a space). A warning
2763 symbol's name is a message to be displayed if the symbol following the
2764 warning symbol is ever referenced.
2768 The symbol is an indirect reference to another symbol (I), a function
2769 to be evaluated during reloc processing (i) or a normal symbol (a
2774 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2775 normal symbol (a space).
2780 The symbol is the name of a function (F) or a file (f) or an object
2781 (O) or just a normal symbol (a space).
2785 @itemx --dynamic-syms
2786 @cindex dynamic symbol table entries, printing
2787 Print the dynamic symbol table entries of the file. This is only
2788 meaningful for dynamic objects, such as certain types of shared
2789 libraries. This is similar to the information provided by the @samp{nm}
2790 program when given the @option{-D} (@option{--dynamic}) option.
2792 The output format is similar to that produced by the @option{--syms}
2793 option, except that an extra field is inserted before the symbol's
2794 name, giving the version information associated with the symbol.
2795 If the version is the default version to be used when resolving
2796 unversioned references to the symbol then it's displayed as is,
2797 otherwise it's put into parentheses.
2799 @item --special-syms
2800 When displaying symbols include those which the target considers to be
2801 special in some way and which would not normally be of interest to the
2806 Print the version number of @command{objdump} and exit.
2809 @itemx --all-headers
2810 @cindex all header information, object file
2811 @cindex header information, all
2812 Display all available header information, including the symbol table and
2813 relocation entries. Using @option{-x} is equivalent to specifying all of
2814 @option{-a -f -h -p -r -t}.
2818 @cindex wide output, printing
2819 Format some lines for output devices that have more than 80 columns.
2820 Also do not truncate symbol names when they are displayed.
2823 @itemx --disassemble-zeroes
2824 Normally the disassembly output will skip blocks of zeroes. This
2825 option directs the disassembler to disassemble those blocks, just like
2832 @c man begin SEEALSO objdump
2833 nm(1), readelf(1), and the Info entries for @file{binutils}.
2841 @cindex archive contents
2842 @cindex symbol index
2844 @c man title ranlib generate an index to an archive
2847 @c man begin SYNOPSIS ranlib
2848 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2852 @c man begin DESCRIPTION ranlib
2854 @command{ranlib} generates an index to the contents of an archive and
2855 stores it in the archive. The index lists each symbol defined by a
2856 member of an archive that is a relocatable object file.
2858 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2860 An archive with such an index speeds up linking to the library and
2861 allows routines in the library to call each other without regard to
2862 their placement in the archive.
2864 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2865 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2870 @c man begin OPTIONS ranlib
2876 Show usage information for @command{ranlib}.
2881 Show the version number of @command{ranlib}.
2884 @cindex deterministic archives
2885 @kindex --enable-deterministic-archives
2886 Operate in @emph{deterministic} mode. The symbol map archive member's
2887 header will show zero for the UID, GID, and timestamp. When this
2888 option is used, multiple runs will produce identical output files.
2890 If @file{binutils} was configured with
2891 @option{--enable-deterministic-archives}, then this mode is on by
2892 default. It can be disabled with the @samp{-U} option, described
2896 Update the timestamp of the symbol map of an archive.
2899 @cindex deterministic archives
2900 @kindex --enable-deterministic-archives
2901 Do @emph{not} operate in @emph{deterministic} mode. This is the
2902 inverse of the @samp{-D} option, above: the archive index will get
2903 actual UID, GID, timestamp, and file mode values.
2905 If @file{binutils} was configured @emph{without}
2906 @option{--enable-deterministic-archives}, then this mode is on by
2914 @c man begin SEEALSO ranlib
2915 ar(1), nm(1), and the Info entries for @file{binutils}.
2923 @cindex section sizes
2925 @c man title size list section sizes and total size of binary files
2928 @c man begin SYNOPSIS size
2929 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
2931 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2933 [@option{-t}|@option{--totals}]
2934 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2935 [@var{objfile}@dots{}]
2939 @c man begin DESCRIPTION size
2941 The @sc{gnu} @command{size} utility lists the section sizes and the total
2942 size for each of the binary files @var{objfile} on its argument list.
2943 By default, one line of output is generated for each file or each
2944 module if the file is an archive.
2946 @var{objfile}@dots{} are the files to be examined. If none are
2947 specified, the file @code{a.out} will be used instead.
2951 @c man begin OPTIONS size
2953 The command-line options have the following meanings:
2959 @itemx --format=@var{compatibility}
2960 @cindex @command{size} display format
2961 Using one of these options, you can choose whether the output from @sc{gnu}
2962 @command{size} resembles output from System V @command{size} (using @option{-A},
2963 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2964 @option{--format=berkeley}). The default is the one-line format similar to
2965 Berkeley's. Alternatively, you can choose the GNU format output
2966 (using @option{-G}, or @option{--format=gnu}), this is similar to
2967 Berkeley's output format, but sizes are counted differently.
2968 @c Bonus for doc-source readers: you can also say --format=strange (or
2969 @c anything else that starts with 's') for sysv, and --format=boring (or
2970 @c anything else that starts with 'b') for Berkeley.
2972 Here is an example of the Berkeley (default) format of output from
2975 $ size --format=Berkeley ranlib size
2976 text data bss dec hex filename
2977 294880 81920 11592 388392 5ed28 ranlib
2978 294880 81920 11888 388688 5ee50 size
2981 The Berkeley style output counts read only data in the @code{text}
2982 column, not in the @code{data} column, the @code{dec} and @code{hex}
2983 columns both display the sum of the @code{text}, @code{data}, and
2984 @code{bss} columns in decimal and hexadecimal respectively.
2986 The GNU format counts read only data in the @code{data} column, not
2987 the @code{text} column, and only displays the sum of the @code{text},
2988 @code{data}, and @code{bss} columns once, in the @code{total} column.
2989 The @option{--radix} option can be used to change the number base for
2990 all columns. Here is the same data displayed with GNU conventions:
2993 $ size --format=GNU ranlib size
2994 text data bss total filename
2995 279880 96920 11592 388392 ranlib
2996 279880 96920 11888 388688 size
3000 This is the same data, but displayed closer to System V conventions:
3003 $ size --format=SysV ranlib size
3021 Show a summary of acceptable arguments and options.
3026 @itemx --radix=@var{number}
3027 @cindex @command{size} number format
3028 @cindex radix for section sizes
3029 Using one of these options, you can control whether the size of each
3030 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
3031 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
3032 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
3033 values (8, 10, 16) are supported. The total size is always given in two
3034 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3035 octal and hexadecimal if you're using @option{-o}.
3038 Print total size of common symbols in each file. When using Berkeley
3039 or GNU format these are included in the bss size.
3043 Show totals of all objects listed (Berkeley or GNU format mode only).
3045 @item --target=@var{bfdname}
3046 @cindex object code format
3047 Specify that the object-code format for @var{objfile} is
3048 @var{bfdname}. This option may not be necessary; @command{size} can
3049 automatically recognize many formats.
3050 @xref{Target Selection}, for more information.
3054 Display the version number of @command{size}.
3060 @c man begin SEEALSO size
3061 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3068 @cindex listings strings
3069 @cindex printing strings
3070 @cindex strings, printing
3072 @c man title strings print the sequences of printable characters in files
3075 @c man begin SYNOPSIS strings
3076 strings [@option{-afovV}] [@option{-}@var{min-len}]
3077 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3078 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3079 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3080 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3081 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3082 [@option{-w}] [@option{--include-all-whitespace}]
3083 [@option{-s}] [@option{--output-separator}@var{sep_string}]
3084 [@option{--help}] [@option{--version}] @var{file}@dots{}
3088 @c man begin DESCRIPTION strings
3090 For each @var{file} given, @sc{gnu} @command{strings} prints the
3091 printable character sequences that are at least 4 characters long (or
3092 the number given with the options below) and are followed by an
3093 unprintable character.
3095 Depending upon how the strings program was configured it will default
3096 to either displaying all the printable sequences that it can find in
3097 each file, or only those sequences that are in loadable, initialized
3098 data sections. If the file type in unrecognizable, or if strings is
3099 reading from stdin then it will always display all of the printable
3100 sequences that it can find.
3102 For backwards compatibility any file that occurs after a command-line
3103 option of just @option{-} will also be scanned in full, regardless of
3104 the presence of any @option{-d} option.
3106 @command{strings} is mainly useful for determining the contents of
3111 @c man begin OPTIONS strings
3117 Scan the whole file, regardless of what sections it contains or
3118 whether those sections are loaded or initialized. Normally this is
3119 the default behaviour, but strings can be configured so that the
3120 @option{-d} is the default instead.
3122 The @option{-} option is position dependent and forces strings to
3123 perform full scans of any file that is mentioned after the @option{-}
3124 on the command line, even if the @option{-d} option has been
3129 Only print strings from initialized, loaded data sections in the
3130 file. This may reduce the amount of garbage in the output, but it
3131 also exposes the strings program to any security flaws that may be
3132 present in the BFD library used to scan and load sections. Strings
3133 can be configured so that this option is the default behaviour. In
3134 such cases the @option{-a} option can be used to avoid using the BFD
3135 library and instead just print all of the strings found in the file.
3138 @itemx --print-file-name
3139 Print the name of the file before each string.
3142 Print a summary of the program usage on the standard output and exit.
3144 @item -@var{min-len}
3145 @itemx -n @var{min-len}
3146 @itemx --bytes=@var{min-len}
3147 Print sequences of characters that are at least @var{min-len} characters
3148 long, instead of the default 4.
3151 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3152 act like @samp{-t d} instead. Since we can not be compatible with both
3153 ways, we simply chose one.
3155 @item -t @var{radix}
3156 @itemx --radix=@var{radix}
3157 Print the offset within the file before each string. The single
3158 character argument specifies the radix of the offset---@samp{o} for
3159 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3161 @item -e @var{encoding}
3162 @itemx --encoding=@var{encoding}
3163 Select the character encoding of the strings that are to be found.
3164 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3165 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3166 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3167 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3168 littleendian. Useful for finding wide character strings. (@samp{l}
3169 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3171 @item -T @var{bfdname}
3172 @itemx --target=@var{bfdname}
3173 @cindex object code format
3174 Specify an object code format other than your system's default format.
3175 @xref{Target Selection}, for more information.
3180 Print the program version number on the standard output and exit.
3183 @itemx --include-all-whitespace
3184 By default tab and space characters are included in the strings that
3185 are displayed, but other whitespace characters, such a newlines and
3186 carriage returns, are not. The @option{-w} option changes this so
3187 that all whitespace characters are considered to be part of a string.
3190 @itemx --output-separator
3191 By default, output strings are delimited by a new-line. This option
3192 allows you to supply any string to be used as the output record
3193 separator. Useful with --include-all-whitespace where strings
3194 may contain new-lines internally.
3200 @c man begin SEEALSO strings
3201 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3202 and the Info entries for @file{binutils}.
3210 @cindex removing symbols
3211 @cindex discarding symbols
3212 @cindex symbols, discarding
3214 @c man title strip discard symbols and other data from object files
3217 @c man begin SYNOPSIS strip
3218 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3219 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3220 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3221 [@option{-s}|@option{--strip-all}]
3222 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3223 [@option{--strip-dwo}]
3224 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3225 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3226 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3227 [@option{-w}|@option{--wildcard}]
3228 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3229 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3230 [@option{--remove-relocations=}@var{sectionpattern}]
3231 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3232 [@option{-D}|@option{--enable-deterministic-archives}]
3233 [@option{-U}|@option{--disable-deterministic-archives}]
3234 [@option{--keep-file-symbols}]
3235 [@option{--only-keep-debug}]
3236 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3237 [@option{--help}] [@option{--info}]
3238 @var{objfile}@dots{}
3242 @c man begin DESCRIPTION strip
3244 @sc{gnu} @command{strip} discards all symbols from object files
3245 @var{objfile}. The list of object files may include archives.
3246 At least one object file must be given.
3248 @command{strip} modifies the files named in its argument,
3249 rather than writing modified copies under different names.
3253 @c man begin OPTIONS strip
3256 @item -F @var{bfdname}
3257 @itemx --target=@var{bfdname}
3258 Treat the original @var{objfile} as a file with the object
3259 code format @var{bfdname}, and rewrite it in the same format.
3260 @xref{Target Selection}, for more information.
3263 Show a summary of the options to @command{strip} and exit.
3266 Display a list showing all architectures and object formats available.
3268 @item -I @var{bfdname}
3269 @itemx --input-target=@var{bfdname}
3270 Treat the original @var{objfile} as a file with the object
3271 code format @var{bfdname}.
3272 @xref{Target Selection}, for more information.
3274 @item -O @var{bfdname}
3275 @itemx --output-target=@var{bfdname}
3276 Replace @var{objfile} with a file in the output format @var{bfdname}.
3277 @xref{Target Selection}, for more information.
3279 @item -R @var{sectionname}
3280 @itemx --remove-section=@var{sectionname}
3281 Remove any section named @var{sectionname} from the output file, in
3282 addition to whatever sections would otherwise be removed. This
3283 option may be given more than once. Note that using this option
3284 inappropriately may make the output file unusable. The wildcard
3285 character @samp{*} may be given at the end of @var{sectionname}. If
3286 so, then any section starting with @var{sectionname} will be removed.
3288 If the first character of @var{sectionpattern} is the exclamation
3289 point (!) then matching sections will not be removed even if an
3290 earlier use of @option{--remove-section} on the same command line
3291 would otherwise remove it. For example:
3294 --remove-section=.text.* --remove-section=!.text.foo
3297 will remove all sections matching the pattern '.text.*', but will not
3298 remove the section '.text.foo'.
3300 @item --remove-relocations=@var{sectionpattern}
3301 Remove relocations from the output file for any section matching
3302 @var{sectionpattern}. This option may be given more than once. Note
3303 that using this option inappropriately may make the output file
3304 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3308 --remove-relocations=.text.*
3311 will remove the relocations for all sections matching the patter
3314 If the first character of @var{sectionpattern} is the exclamation
3315 point (!) then matching sections will not have their relocation
3316 removed even if an earlier use of @option{--remove-relocations} on the
3317 same command line would otherwise cause the relocations to be removed.
3321 --remove-relocations=.text.* --remove-relocations=!.text.foo
3324 will remove all relocations for sections matching the pattern
3325 '.text.*', but will not remove relocations for the section
3335 @itemx --strip-debug
3336 Remove debugging symbols only.
3339 Remove the contents of all DWARF .dwo sections, leaving the
3340 remaining debugging sections and all symbols intact.
3341 See the description of this option in the @command{objcopy} section
3342 for more information.
3344 @item --strip-unneeded
3345 Remove all symbols that are not needed for relocation processing.
3347 @item -K @var{symbolname}
3348 @itemx --keep-symbol=@var{symbolname}
3349 When stripping symbols, keep symbol @var{symbolname} even if it would
3350 normally be stripped. This option may be given more than once.
3353 @itemx --merge-notes
3354 @itemx --no-merge-notes
3355 For ELF files, attempt (or do not attempt) to reduce the size of any
3356 SHT_NOTE type sections by removing duplicate notes. The default is to
3357 attempt this reduction unless stripping debug or DWO information.
3359 @item -N @var{symbolname}
3360 @itemx --strip-symbol=@var{symbolname}
3361 Remove symbol @var{symbolname} from the source file. This option may be
3362 given more than once, and may be combined with strip options other than
3366 Put the stripped output in @var{file}, rather than replacing the
3367 existing file. When this argument is used, only one @var{objfile}
3368 argument may be specified.
3371 @itemx --preserve-dates
3372 Preserve the access and modification dates of the file.
3375 @itemx --enable-deterministic-archives
3376 @cindex deterministic archives
3377 @kindex --enable-deterministic-archives
3378 Operate in @emph{deterministic} mode. When copying archive members
3379 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3380 and use consistent file modes for all files.
3382 If @file{binutils} was configured with
3383 @option{--enable-deterministic-archives}, then this mode is on by default.
3384 It can be disabled with the @samp{-U} option, below.
3387 @itemx --disable-deterministic-archives
3388 @cindex deterministic archives
3389 @kindex --enable-deterministic-archives
3390 Do @emph{not} operate in @emph{deterministic} mode. This is the
3391 inverse of the @option{-D} option, above: when copying archive members
3392 and writing the archive index, use their actual UID, GID, timestamp,
3393 and file mode values.
3395 This is the default unless @file{binutils} was configured with
3396 @option{--enable-deterministic-archives}.
3400 Permit regular expressions in @var{symbolname}s used in other command
3401 line options. The question mark (?), asterisk (*), backslash (\) and
3402 square brackets ([]) operators can be used anywhere in the symbol
3403 name. If the first character of the symbol name is the exclamation
3404 point (!) then the sense of the switch is reversed for that symbol.
3411 would cause strip to only keep symbols that start with the letters
3412 ``fo'', but to discard the symbol ``foo''.
3415 @itemx --discard-all
3416 Remove non-global symbols.
3419 @itemx --discard-locals
3420 Remove compiler-generated local symbols.
3421 (These usually start with @samp{L} or @samp{.}.)
3423 @item --keep-file-symbols
3424 When stripping a file, perhaps with @option{--strip-debug} or
3425 @option{--strip-unneeded}, retain any symbols specifying source file names,
3426 which would otherwise get stripped.
3428 @item --only-keep-debug
3429 Strip a file, emptying the contents of any sections that would not be
3430 stripped by @option{--strip-debug} and leaving the debugging sections
3431 intact. In ELF files, this preserves all the note sections in the
3434 Note - the section headers of the stripped sections are preserved,
3435 including their sizes, but the contents of the section are discarded.
3436 The section headers are preserved so that other tools can match up the
3437 debuginfo file with the real executable, even if that executable has
3438 been relocated to a different address space.
3440 The intention is that this option will be used in conjunction with
3441 @option{--add-gnu-debuglink} to create a two part executable. One a
3442 stripped binary which will occupy less space in RAM and in a
3443 distribution and the second a debugging information file which is only
3444 needed if debugging abilities are required. The suggested procedure
3445 to create these files is as follows:
3448 @item Link the executable as normal. Assuming that it is called
3450 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3451 create a file containing the debugging info.
3452 @item Run @code{objcopy --strip-debug foo} to create a
3453 stripped executable.
3454 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3455 to add a link to the debugging info into the stripped executable.
3458 Note---the choice of @code{.dbg} as an extension for the debug info
3459 file is arbitrary. Also the @code{--only-keep-debug} step is
3460 optional. You could instead do this:
3463 @item Link the executable as normal.
3464 @item Copy @code{foo} to @code{foo.full}
3465 @item Run @code{strip --strip-debug foo}
3466 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3469 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3470 full executable. It does not have to be a file created by the
3471 @option{--only-keep-debug} switch.
3473 Note---this switch is only intended for use on fully linked files. It
3474 does not make sense to use it on object files where the debugging
3475 information may be incomplete. Besides the gnu_debuglink feature
3476 currently only supports the presence of one filename containing
3477 debugging information, not multiple filenames on a one-per-object-file
3482 Show the version number for @command{strip}.
3486 Verbose output: list all object files modified. In the case of
3487 archives, @samp{strip -v} lists all members of the archive.
3493 @c man begin SEEALSO strip
3494 the Info entries for @file{binutils}.
3498 @node c++filt, addr2line, strip, Top
3502 @cindex demangling C++ symbols
3504 @c man title cxxfilt demangle C++ and Java symbols
3507 @c man begin SYNOPSIS cxxfilt
3508 c++filt [@option{-_}|@option{--strip-underscore}]
3509 [@option{-n}|@option{--no-strip-underscore}]
3510 [@option{-p}|@option{--no-params}]
3511 [@option{-t}|@option{--types}]
3512 [@option{-i}|@option{--no-verbose}]
3513 [@option{-r}|@option{--no-recurse-limit}]
3514 [@option{-R}|@option{--recurse-limit}]
3515 [@option{-s} @var{format}|@option{--format=}@var{format}]
3516 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3520 @c man begin DESCRIPTION cxxfilt
3523 The C++ and Java languages provide function overloading, which means
3524 that you can write many functions with the same name, providing that
3525 each function takes parameters of different types. In order to be
3526 able to distinguish these similarly named functions C++ and Java
3527 encode them into a low-level assembler name which uniquely identifies
3528 each different version. This process is known as @dfn{mangling}. The
3530 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3531 MS-DOS this program is named @command{CXXFILT}.}
3532 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3533 names into user-level names so that they can be read.
3535 Every alphanumeric word (consisting of letters, digits, underscores,
3536 dollars, or periods) seen in the input is a potential mangled name.
3537 If the name decodes into a C++ name, the C++ name replaces the
3538 low-level name in the output, otherwise the original word is output.
3539 In this way you can pass an entire assembler source file, containing
3540 mangled names, through @command{c++filt} and see the same source file
3541 containing demangled names.
3543 You can also use @command{c++filt} to decipher individual symbols by
3544 passing them on the command line:
3547 c++filt @var{symbol}
3550 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3551 names from the standard input instead. All the results are printed on
3552 the standard output. The difference between reading names from the
3553 command line versus reading names from the standard input is that
3554 command-line arguments are expected to be just mangled names and no
3555 checking is performed to separate them from surrounding text. Thus
3562 will work and demangle the name to ``f()'' whereas:
3568 will not work. (Note the extra comma at the end of the mangled
3569 name which makes it invalid). This command however will work:
3572 echo _Z1fv, | c++filt -n
3575 and will display ``f(),'', i.e., the demangled name followed by a
3576 trailing comma. This behaviour is because when the names are read
3577 from the standard input it is expected that they might be part of an
3578 assembler source file where there might be extra, extraneous
3579 characters trailing after a mangled name. For example:
3582 .type _Z1fv, @@function
3587 @c man begin OPTIONS cxxfilt
3591 @itemx --strip-underscore
3592 On some systems, both the C and C++ compilers put an underscore in front
3593 of every name. For example, the C name @code{foo} gets the low-level
3594 name @code{_foo}. This option removes the initial underscore. Whether
3595 @command{c++filt} removes the underscore by default is target dependent.
3598 @itemx --no-strip-underscore
3599 Do not remove the initial underscore.
3603 When demangling the name of a function, do not display the types of
3604 the function's parameters.
3608 Attempt to demangle types as well as function names. This is disabled
3609 by default since mangled types are normally only used internally in
3610 the compiler, and they can be confused with non-mangled names. For example,
3611 a function called ``a'' treated as a mangled type name would be
3612 demangled to ``signed char''.
3616 Do not include implementation details (if any) in the demangled
3621 @itemx --recurse-limit
3622 @itemx --no-recurse-limit
3623 @itemx --recursion-limit
3624 @itemx --no-recursion-limit
3625 Enables or disables a limit on the amount of recursion performed
3626 whilst demangling strings. Since the name mangling formats allow for
3627 an inifinite level of recursion it is possible to create strings whose
3628 decoding will exhaust the amount of stack space available on the host
3629 machine, triggering a memory fault. The limit tries to prevent this
3630 from happening by restricting recursion to 2048 levels of nesting.
3632 The default is for this limit to be enabled, but disabling it may be
3633 necessary in order to demangle truly complicated names. Note however
3634 that if the recursion limit is disabled then stack exhaustion is
3635 possible and any bug reports about such an event will be rejected.
3637 The @option{-r} option is a synonym for the
3638 @option{--no-recurse-limit} option. The @option{-R} option is a
3639 synonym for the @option{--recurse-limit} option.
3641 @item -s @var{format}
3642 @itemx --format=@var{format}
3643 @command{c++filt} can decode various methods of mangling, used by
3644 different compilers. The argument to this option selects which
3649 Automatic selection based on executable (the default method)
3651 the one used by the @sc{gnu} C++ compiler (g++)
3653 the one used by the Lucid compiler (lcc)
3655 the one specified by the C++ Annotated Reference Manual
3657 the one used by the HP compiler (aCC)
3659 the one used by the EDG compiler
3661 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3663 the one used by the @sc{gnu} Java compiler (gcj)
3665 the one used by the @sc{gnu} Ada compiler (GNAT).
3669 Print a summary of the options to @command{c++filt} and exit.
3672 Print the version number of @command{c++filt} and exit.
3678 @c man begin SEEALSO cxxfilt
3679 the Info entries for @file{binutils}.
3684 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3685 user interface are subject to change in future releases. In particular,
3686 a command-line option may be required in the future to decode a name
3687 passed as an argument on the command line; in other words,
3690 c++filt @var{symbol}
3694 may in a future release become
3697 c++filt @var{option} @var{symbol}
3705 @cindex address to file name and line number
3707 @c man title addr2line convert addresses into file names and line numbers
3710 @c man begin SYNOPSIS addr2line
3711 addr2line [@option{-a}|@option{--addresses}]
3712 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3713 [@option{-C}|@option{--demangle}[=@var{style}]]
3714 [@option{-r}|@option{--no-recurse-limit}]
3715 [@option{-R}|@option{--recurse-limit}]
3716 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3717 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3718 [@option{-i}|@option{--inlines}]
3719 [@option{-p}|@option{--pretty-print}]
3720 [@option{-j}|@option{--section=}@var{name}]
3721 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3726 @c man begin DESCRIPTION addr2line
3728 @command{addr2line} translates addresses into file names and line numbers.
3729 Given an address in an executable or an offset in a section of a relocatable
3730 object, it uses the debugging information to figure out which file name and
3731 line number are associated with it.
3733 The executable or relocatable object to use is specified with the @option{-e}
3734 option. The default is the file @file{a.out}. The section in the relocatable
3735 object to use is specified with the @option{-j} option.
3737 @command{addr2line} has two modes of operation.
3739 In the first, hexadecimal addresses are specified on the command line,
3740 and @command{addr2line} displays the file name and line number for each
3743 In the second, @command{addr2line} reads hexadecimal addresses from
3744 standard input, and prints the file name and line number for each
3745 address on standard output. In this mode, @command{addr2line} may be used
3746 in a pipe to convert dynamically chosen addresses.
3748 The format of the output is @samp{FILENAME:LINENO}. By default
3749 each input address generates one line of output.
3751 Two options can generate additional lines before each
3752 @samp{FILENAME:LINENO} line (in that order).
3754 If the @option{-a} option is used then a line with the input address
3757 If the @option{-f} option is used, then a line with the
3758 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3759 containing the address.
3761 One option can generate additional lines after the
3762 @samp{FILENAME:LINENO} line.
3764 If the @option{-i} option is used and the code at the given address is
3765 present there because of inlining by the compiler then additional
3766 lines are displayed afterwards. One or two extra lines (if the
3767 @option{-f} option is used) are displayed for each inlined function.
3769 Alternatively if the @option{-p} option is used then each input
3770 address generates a single, long, output line containing the address,
3771 the function name, the file name and the line number. If the
3772 @option{-i} option has also been used then any inlined functions will
3773 be displayed in the same manner, but on separate lines, and prefixed
3774 by the text @samp{(inlined by)}.
3776 If the file name or function name can not be determined,
3777 @command{addr2line} will print two question marks in their place. If the
3778 line number can not be determined, @command{addr2line} will print 0.
3782 @c man begin OPTIONS addr2line
3784 The long and short forms of options, shown here as alternatives, are
3790 Display the address before the function name, file and line number
3791 information. The address is printed with a @samp{0x} prefix to easily
3794 @item -b @var{bfdname}
3795 @itemx --target=@var{bfdname}
3796 @cindex object code format
3797 Specify that the object-code format for the object files is
3801 @itemx --demangle[=@var{style}]
3802 @cindex demangling in objdump
3803 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3804 Besides removing any initial underscore prepended by the system, this
3805 makes C++ function names readable. Different compilers have different
3806 mangling styles. The optional demangling style argument can be used to
3807 choose an appropriate demangling style for your compiler. @xref{c++filt},
3808 for more information on demangling.
3810 @item -e @var{filename}
3811 @itemx --exe=@var{filename}
3812 Specify the name of the executable for which addresses should be
3813 translated. The default file is @file{a.out}.
3817 Display function names as well as file and line number information.
3821 Display only the base of each file name.
3825 If the address belongs to a function that was inlined, the source
3826 information for all enclosing scopes back to the first non-inlined
3827 function will also be printed. For example, if @code{main} inlines
3828 @code{callee1} which inlines @code{callee2}, and address is from
3829 @code{callee2}, the source information for @code{callee1} and @code{main}
3830 will also be printed.
3834 Read offsets relative to the specified section instead of absolute addresses.
3837 @itemx --pretty-print
3838 Make the output more human friendly: each location are printed on one line.
3839 If option @option{-i} is specified, lines for all enclosing scopes are
3840 prefixed with @samp{(inlined by)}.
3844 @itemx --recurse-limit
3845 @itemx --no-recurse-limit
3846 @itemx --recursion-limit
3847 @itemx --no-recursion-limit
3848 Enables or disables a limit on the amount of recursion performed
3849 whilst demangling strings. Since the name mangling formats allow for
3850 an inifinite level of recursion it is possible to create strings whose
3851 decoding will exhaust the amount of stack space available on the host
3852 machine, triggering a memory fault. The limit tries to prevent this
3853 from happening by restricting recursion to 2048 levels of nesting.
3855 The default is for this limit to be enabled, but disabling it may be
3856 necessary in order to demangle truly complicated names. Note however
3857 that if the recursion limit is disabled then stack exhaustion is
3858 possible and any bug reports about such an event will be rejected.
3860 The @option{-r} option is a synonym for the
3861 @option{--no-recurse-limit} option. The @option{-R} option is a
3862 synonym for the @option{--recurse-limit} option.
3864 Note this option is only effective if the @option{-C} or
3865 @option{--demangle} option has been enabled.
3872 @c man begin SEEALSO addr2line
3873 Info entries for @file{binutils}.
3880 @command{windmc} may be used to generator Windows message resources.
3883 @emph{Warning:} @command{windmc} is not always built as part of the binary
3884 utilities, since it is only useful for Windows targets.
3887 @c man title windmc generates Windows message resources
3890 @c man begin SYNOPSIS windmc
3891 windmc [options] input-file
3895 @c man begin DESCRIPTION windmc
3897 @command{windmc} reads message definitions from an input file (.mc) and
3898 translate them into a set of output files. The output files may be of
3903 A C header file containing the message definitions.
3906 A resource file compilable by the @command{windres} tool.
3909 One or more binary files containing the resource data for a specific
3913 A C include file that maps message id's to their symbolic name.
3916 The exact description of these different formats is available in
3917 documentation from Microsoft.
3919 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3920 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3921 Windows Message Compiler.
3925 @c man begin OPTIONS windmc
3930 Specifies that the input file specified is ASCII. This is the default
3935 Specifies that messages in the output @code{bin} files should be in ASCII
3940 Specifies that @code{bin} filenames should have to be prefixed by the
3941 basename of the source file.
3945 Sets the customer bit in all message id's.
3947 @item -C @var{codepage}
3948 @itemx --codepage_in @var{codepage}
3949 Sets the default codepage to be used to convert input file to UTF16. The
3950 default is ocdepage 1252.
3953 @itemx --decimal_values
3954 Outputs the constants in the header file in decimal. Default is using
3958 @itemx --extension @var{ext}
3959 The extension for the header file. The default is .h extension.
3961 @item -F @var{target}
3962 @itemx --target @var{target}
3963 Specify the BFD format to use for a bin file as output. This
3964 is a BFD target name; you can use the @option{--help} option to see a list
3965 of supported targets. Normally @command{windmc} will use the default
3966 format, which is the first one listed by the @option{--help} option.
3968 @ref{Target Selection}.
3972 @itemx --headerdir @var{path}
3973 The target directory of the generated header file. The default is the
3978 Displays a list of command-line options and then exits.
3980 @item -m @var{characters}
3981 @itemx --maxlength @var{characters}
3982 Instructs @command{windmc} to generate a warning if the length
3983 of any message exceeds the number specified.
3986 @itemx --nullterminate
3987 Terminate message text in @code{bin} files by zero. By default they are
3988 terminated by CR/LF.
3991 @itemx --hresult_use
3992 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3993 file, using HRESULT definitions. Status codes are used if the flag is not
3996 @item -O @var{codepage}
3997 @itemx --codepage_out @var{codepage}
3998 Sets the default codepage to be used to output text files. The default
4002 @itemx --rcdir @var{path}
4003 The target directory for the generated @code{rc} script and the generated
4004 @code{bin} files that the resource compiler script includes. The default
4005 is the current directory.
4009 Specifies that the input file is UTF16.
4012 @itemx --unicode_out
4013 Specifies that messages in the output @code{bin} file should be in UTF16
4014 format. This is the default behaviour.
4018 Enable verbose mode.
4022 Prints the version number for @command{windmc}.
4025 @itemx --xdgb @var{path}
4026 The path of the @code{dbg} C include file that maps message id's to the
4027 symbolic name. No such file is generated without specifying the switch.
4033 @c man begin SEEALSO windmc
4034 the Info entries for @file{binutils}.
4041 @command{windres} may be used to manipulate Windows resources.
4044 @emph{Warning:} @command{windres} is not always built as part of the binary
4045 utilities, since it is only useful for Windows targets.
4048 @c man title windres manipulate Windows resources
4051 @c man begin SYNOPSIS windres
4052 windres [options] [input-file] [output-file]
4056 @c man begin DESCRIPTION windres
4058 @command{windres} reads resources from an input file and copies them into
4059 an output file. Either file may be in one of three formats:
4063 A text format read by the Resource Compiler.
4066 A binary format generated by the Resource Compiler.
4069 A COFF object or executable.
4072 The exact description of these different formats is available in
4073 documentation from Microsoft.
4075 When @command{windres} converts from the @code{rc} format to the @code{res}
4076 format, it is acting like the Windows Resource Compiler. When
4077 @command{windres} converts from the @code{res} format to the @code{coff}
4078 format, it is acting like the Windows @code{CVTRES} program.
4080 When @command{windres} generates an @code{rc} file, the output is similar
4081 but not identical to the format expected for the input. When an input
4082 @code{rc} file refers to an external filename, an output @code{rc} file
4083 will instead include the file contents.
4085 If the input or output format is not specified, @command{windres} will
4086 guess based on the file name, or, for the input file, the file contents.
4087 A file with an extension of @file{.rc} will be treated as an @code{rc}
4088 file, a file with an extension of @file{.res} will be treated as a
4089 @code{res} file, and a file with an extension of @file{.o} or
4090 @file{.exe} will be treated as a @code{coff} file.
4092 If no output file is specified, @command{windres} will print the resources
4093 in @code{rc} format to standard output.
4095 The normal use is for you to write an @code{rc} file, use @command{windres}
4096 to convert it to a COFF object file, and then link the COFF file into
4097 your application. This will make the resources described in the
4098 @code{rc} file available to Windows.
4102 @c man begin OPTIONS windres
4105 @item -i @var{filename}
4106 @itemx --input @var{filename}
4107 The name of the input file. If this option is not used, then
4108 @command{windres} will use the first non-option argument as the input file
4109 name. If there are no non-option arguments, then @command{windres} will
4110 read from standard input. @command{windres} can not read a COFF file from
4113 @item -o @var{filename}
4114 @itemx --output @var{filename}
4115 The name of the output file. If this option is not used, then
4116 @command{windres} will use the first non-option argument, after any used
4117 for the input file name, as the output file name. If there is no
4118 non-option argument, then @command{windres} will write to standard output.
4119 @command{windres} can not write a COFF file to standard output. Note,
4120 for compatibility with @command{rc} the option @option{-fo} is also
4121 accepted, but its use is not recommended.
4123 @item -J @var{format}
4124 @itemx --input-format @var{format}
4125 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4126 @samp{coff}. If no input format is specified, @command{windres} will
4127 guess, as described above.
4129 @item -O @var{format}
4130 @itemx --output-format @var{format}
4131 The output format to generate. @var{format} may be @samp{res},
4132 @samp{rc}, or @samp{coff}. If no output format is specified,
4133 @command{windres} will guess, as described above.
4135 @item -F @var{target}
4136 @itemx --target @var{target}
4137 Specify the BFD format to use for a COFF file as input or output. This
4138 is a BFD target name; you can use the @option{--help} option to see a list
4139 of supported targets. Normally @command{windres} will use the default
4140 format, which is the first one listed by the @option{--help} option.
4142 @ref{Target Selection}.
4145 @item --preprocessor @var{program}
4146 When @command{windres} reads an @code{rc} file, it runs it through the C
4147 preprocessor first. This option may be used to specify the preprocessor
4148 to use, including any leading arguments. The default preprocessor
4149 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
4151 @item --preprocessor-arg @var{option}
4152 When @command{windres} reads an @code{rc} file, it runs it through
4153 the C preprocessor first. This option may be used to specify additional
4154 text to be passed to preprocessor on its command line.
4155 This option can be used multiple times to add multiple options to the
4156 preprocessor command line.
4158 @item -I @var{directory}
4159 @itemx --include-dir @var{directory}
4160 Specify an include directory to use when reading an @code{rc} file.
4161 @command{windres} will pass this to the preprocessor as an @option{-I}
4162 option. @command{windres} will also search this directory when looking for
4163 files named in the @code{rc} file. If the argument passed to this command
4164 matches any of the supported @var{formats} (as described in the @option{-J}
4165 option), it will issue a deprecation warning, and behave just like the
4166 @option{-J} option. New programs should not use this behaviour. If a
4167 directory happens to match a @var{format}, simple prefix it with @samp{./}
4168 to disable the backward compatibility.
4170 @item -D @var{target}
4171 @itemx --define @var{sym}[=@var{val}]
4172 Specify a @option{-D} option to pass to the preprocessor when reading an
4175 @item -U @var{target}
4176 @itemx --undefine @var{sym}
4177 Specify a @option{-U} option to pass to the preprocessor when reading an
4181 Ignored for compatibility with rc.
4184 Enable verbose mode. This tells you what the preprocessor is if you
4188 @item --codepage @var{val}
4189 Specify the default codepage to use when reading an @code{rc} file.
4190 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4191 codepage code. The valid range is from zero up to 0xffff, but the
4192 validity of the codepage is host and configuration dependent.
4195 @item --language @var{val}
4196 Specify the default language to use when reading an @code{rc} file.
4197 @var{val} should be a hexadecimal language code. The low eight bits are
4198 the language, and the high eight bits are the sublanguage.
4200 @item --use-temp-file
4201 Use a temporary file to instead of using popen to read the output of
4202 the preprocessor. Use this option if the popen implementation is buggy
4203 on the host (eg., certain non-English language versions of Windows 95 and
4204 Windows 98 are known to have buggy popen where the output will instead
4207 @item --no-use-temp-file
4208 Use popen, not a temporary file, to read the output of the preprocessor.
4209 This is the default behaviour.
4213 Prints a usage summary.
4217 Prints the version number for @command{windres}.
4220 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4221 this will turn on parser debugging.
4227 @c man begin SEEALSO windres
4228 the Info entries for @file{binutils}.
4237 @command{dlltool} is used to create the files needed to create dynamic
4238 link libraries (DLLs) on systems which understand PE format image
4239 files such as Windows. A DLL contains an export table which contains
4240 information that the runtime loader needs to resolve references from a
4241 referencing program.
4243 The export table is generated by this program by reading in a
4244 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4245 will be in the DLL. A @file{.o} file can contain information in
4246 special @samp{.drectve} sections with export information.
4249 @emph{Note:} @command{dlltool} is not always built as part of the
4250 binary utilities, since it is only useful for those targets which
4254 @c man title dlltool create files needed to build and use DLLs
4257 @c man begin SYNOPSIS dlltool
4258 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4259 [@option{-b}|@option{--base-file} @var{base-file-name}]
4260 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4261 [@option{-z}|@option{--output-def} @var{def-file-name}]
4262 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4263 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4264 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4265 [@option{--exclude-symbols} @var{list}]
4266 [@option{--no-default-excludes}]
4267 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4268 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4269 [@option{-a}|@option{--add-indirect}]
4270 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4271 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4272 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4273 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4274 [@option{--use-nul-prefixed-import-tables}]
4275 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4276 [@option{-i}|@option{--interwork}]
4277 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4278 [@option{-v}|@option{--verbose}]
4279 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4280 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4281 [object-file @dots{}]
4285 @c man begin DESCRIPTION dlltool
4287 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4288 @option{-b} options as well as object files specified on the command
4289 line. It then processes these inputs and if the @option{-e} option has
4290 been specified it creates a exports file. If the @option{-l} option
4291 has been specified it creates a library file and if the @option{-z} option
4292 has been specified it creates a def file. Any or all of the @option{-e},
4293 @option{-l} and @option{-z} options can be present in one invocation of
4296 When creating a DLL, along with the source for the DLL, it is necessary
4297 to have three other files. @command{dlltool} can help with the creation of
4300 The first file is a @file{.def} file which specifies which functions are
4301 exported from the DLL, which functions the DLL imports, and so on. This
4302 is a text file and can be created by hand, or @command{dlltool} can be used
4303 to create it using the @option{-z} option. In this case @command{dlltool}
4304 will scan the object files specified on its command line looking for
4305 those functions which have been specially marked as being exported and
4306 put entries for them in the @file{.def} file it creates.
4308 In order to mark a function as being exported from a DLL, it needs to
4309 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4310 section of the object file. This can be done in C by using the
4314 asm (".section .drectve");
4315 asm (".ascii \"-export:my_func\"");
4317 int my_func (void) @{ @dots{} @}
4320 The second file needed for DLL creation is an exports file. This file
4321 is linked with the object files that make up the body of the DLL and it
4322 handles the interface between the DLL and the outside world. This is a
4323 binary file and it can be created by giving the @option{-e} option to
4324 @command{dlltool} when it is creating or reading in a @file{.def} file.
4326 The third file needed for DLL creation is the library file that programs
4327 will link with in order to access the functions in the DLL (an `import
4328 library'). This file can be created by giving the @option{-l} option to
4329 dlltool when it is creating or reading in a @file{.def} file.
4331 If the @option{-y} option is specified, dlltool generates a delay-import
4332 library that can be used instead of the normal import library to allow
4333 a program to link to the dll only as soon as an imported function is
4334 called for the first time. The resulting executable will need to be
4335 linked to the static delayimp library containing __delayLoadHelper2(),
4336 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4338 @command{dlltool} builds the library file by hand, but it builds the
4339 exports file by creating temporary files containing assembler statements
4340 and then assembling these. The @option{-S} command-line option can be
4341 used to specify the path to the assembler that dlltool will use,
4342 and the @option{-f} option can be used to pass specific flags to that
4343 assembler. The @option{-n} can be used to prevent dlltool from deleting
4344 these temporary assembler files when it is done, and if @option{-n} is
4345 specified twice then this will prevent dlltool from deleting the
4346 temporary object files it used to build the library.
4348 Here is an example of creating a DLL from a source file @samp{dll.c} and
4349 also creating a program (from an object file called @samp{program.o})
4354 dlltool -e exports.o -l dll.lib dll.o
4355 gcc dll.o exports.o -o dll.dll
4356 gcc program.o dll.lib -o program
4360 @command{dlltool} may also be used to query an existing import library
4361 to determine the name of the DLL to which it is associated. See the
4362 description of the @option{-I} or @option{--identify} option.
4366 @c man begin OPTIONS dlltool
4368 The command-line options have the following meanings:
4372 @item -d @var{filename}
4373 @itemx --input-def @var{filename}
4374 @cindex input .def file
4375 Specifies the name of a @file{.def} file to be read in and processed.
4377 @item -b @var{filename}
4378 @itemx --base-file @var{filename}
4380 Specifies the name of a base file to be read in and processed. The
4381 contents of this file will be added to the relocation section in the
4382 exports file generated by dlltool.
4384 @item -e @var{filename}
4385 @itemx --output-exp @var{filename}
4386 Specifies the name of the export file to be created by dlltool.
4388 @item -z @var{filename}
4389 @itemx --output-def @var{filename}
4390 Specifies the name of the @file{.def} file to be created by dlltool.
4392 @item -l @var{filename}
4393 @itemx --output-lib @var{filename}
4394 Specifies the name of the library file to be created by dlltool.
4396 @item -y @var{filename}
4397 @itemx --output-delaylib @var{filename}
4398 Specifies the name of the delay-import library file to be created by dlltool.
4400 @item --export-all-symbols
4401 Treat all global and weak defined symbols found in the input object
4402 files as symbols to be exported. There is a small list of symbols which
4403 are not exported by default; see the @option{--no-default-excludes}
4404 option. You may add to the list of symbols to not export by using the
4405 @option{--exclude-symbols} option.
4407 @item --no-export-all-symbols
4408 Only export symbols explicitly listed in an input @file{.def} file or in
4409 @samp{.drectve} sections in the input object files. This is the default
4410 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4411 attributes in the source code.
4413 @item --exclude-symbols @var{list}
4414 Do not export the symbols in @var{list}. This is a list of symbol names
4415 separated by comma or colon characters. The symbol names should not
4416 contain a leading underscore. This is only meaningful when
4417 @option{--export-all-symbols} is used.
4419 @item --no-default-excludes
4420 When @option{--export-all-symbols} is used, it will by default avoid
4421 exporting certain special symbols. The current list of symbols to avoid
4422 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4423 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4424 to go ahead and export these special symbols. This is only meaningful
4425 when @option{--export-all-symbols} is used.
4428 @itemx --as @var{path}
4429 Specifies the path, including the filename, of the assembler to be used
4430 to create the exports file.
4432 @item -f @var{options}
4433 @itemx --as-flags @var{options}
4434 Specifies any specific command-line options to be passed to the
4435 assembler when building the exports file. This option will work even if
4436 the @option{-S} option is not used. This option only takes one argument,
4437 and if it occurs more than once on the command line, then later
4438 occurrences will override earlier occurrences. So if it is necessary to
4439 pass multiple options to the assembler they should be enclosed in
4443 @itemx --dll-name @var{name}
4444 Specifies the name to be stored in the @file{.def} file as the name of
4445 the DLL when the @option{-e} option is used. If this option is not
4446 present, then the filename given to the @option{-e} option will be
4447 used as the name of the DLL.
4449 @item -m @var{machine}
4450 @itemx -machine @var{machine}
4451 Specifies the type of machine for which the library file should be
4452 built. @command{dlltool} has a built in default type, depending upon how
4453 it was created, but this option can be used to override that. This is
4454 normally only useful when creating DLLs for an ARM processor, when the
4455 contents of the DLL are actually encode using Thumb instructions.
4458 @itemx --add-indirect
4459 Specifies that when @command{dlltool} is creating the exports file it
4460 should add a section which allows the exported functions to be
4461 referenced without using the import library. Whatever the hell that
4465 @itemx --add-underscore
4466 Specifies that when @command{dlltool} is creating the exports file it
4467 should prepend an underscore to the names of @emph{all} exported symbols.
4469 @item --no-leading-underscore
4470 @item --leading-underscore
4471 Specifies whether standard symbol should be forced to be prefixed, or
4474 @item --add-stdcall-underscore
4475 Specifies that when @command{dlltool} is creating the exports file it
4476 should prepend an underscore to the names of exported @emph{stdcall}
4477 functions. Variable names and non-stdcall function names are not modified.
4478 This option is useful when creating GNU-compatible import libs for third
4479 party DLLs that were built with MS-Windows tools.
4483 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4484 of stdcall functions that will be imported from the DLL. This is
4485 useful when creating an import library for a DLL which exports stdcall
4486 functions but without the usual @samp{@@<number>} symbol name suffix.
4488 This does not change the naming of symbols provided by the import library
4489 to programs linked against it, but only the entries in the import table
4490 (ie the .idata section).
4493 @itemx --add-stdcall-alias
4494 Specifies that when @command{dlltool} is creating the exports file it
4495 should add aliases for stdcall symbols without @samp{@@ <number>}
4496 in addition to the symbols with @samp{@@ <number>}.
4499 @itemx --ext-prefix-alias @var{prefix}
4500 Causes @command{dlltool} to create external aliases for all DLL
4501 imports with the specified prefix. The aliases are created for both
4502 external and import symbols with no leading underscore.
4506 Specifies that when @command{dlltool} is creating the exports and library
4507 files it should omit the @code{.idata4} section. This is for compatibility
4508 with certain operating systems.
4510 @item --use-nul-prefixed-import-tables
4511 Specifies that when @command{dlltool} is creating the exports and library
4512 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4513 element. This emulates old gnu import library generation of
4514 @code{dlltool}. By default this option is turned off.
4518 Specifies that when @command{dlltool} is creating the exports and library
4519 files it should omit the @code{.idata5} section. This is for compatibility
4520 with certain operating systems.
4522 @item -I @var{filename}
4523 @itemx --identify @var{filename}
4524 Specifies that @command{dlltool} should inspect the import library
4525 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4526 of the associated DLL(s). This can be performed in addition to any
4527 other operations indicated by the other options and arguments.
4528 @command{dlltool} fails if the import library does not exist or is not
4529 actually an import library. See also @option{--identify-strict}.
4531 @item --identify-strict
4532 Modifies the behavior of the @option{--identify} option, such
4533 that an error is reported if @var{filename} is associated with
4538 Specifies that @command{dlltool} should mark the objects in the library
4539 file and exports file that it produces as supporting interworking
4540 between ARM and Thumb code.
4544 Makes @command{dlltool} preserve the temporary assembler files it used to
4545 create the exports file. If this option is repeated then dlltool will
4546 also preserve the temporary object files it uses to create the library
4549 @item -t @var{prefix}
4550 @itemx --temp-prefix @var{prefix}
4551 Makes @command{dlltool} use @var{prefix} when constructing the names of
4552 temporary assembler and object files. By default, the temp file prefix
4553 is generated from the pid.
4557 Make dlltool describe what it is doing.
4561 Displays a list of command-line options and then exits.
4565 Displays dlltool's version number and then exits.
4572 * def file format:: The format of the dlltool @file{.def} file
4575 @node def file format
4576 @section The format of the @command{dlltool} @file{.def} file
4578 A @file{.def} file contains any number of the following commands:
4582 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4583 The result is going to be named @var{name}@code{.exe}.
4585 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4586 The result is going to be named @var{name}@code{.dll}.
4587 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4588 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4591 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4592 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4593 Declares @var{name1} as an exported symbol from the DLL, with optional
4594 ordinal number @var{integer}, or declares @var{name1} as an alias
4595 (forward) of the function @var{external-name} in the DLL.
4596 If @var{its_name} is specified, this name is used as string in export table.
4598 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4599 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4600 If you want to use LIBRARY as name then you need to quote it.
4602 @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{]} *}
4603 Declares that @var{external-name} or the exported function whose
4604 ordinal number is @var{integer} is to be imported from the file
4605 @var{module-name}. If @var{internal-name} is specified then this is
4606 the name that the imported function will be referred to in the body of
4608 If @var{its_name} is specified, this name is used as string in import table.
4609 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4610 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4611 If you want to use LIBRARY as name then you need to quote it.
4613 @item @code{DESCRIPTION} @var{string}
4614 Puts @var{string} into the output @file{.exp} file in the
4615 @code{.rdata} section.
4617 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4618 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4619 Generates @code{--stack} or @code{--heap}
4620 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4621 section. The linker will see this and act upon it.
4623 @item @code{CODE} @var{attr} @code{+}
4624 @item @code{DATA} @var{attr} @code{+}
4625 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4626 Generates @code{--attr} @var{section-name} @var{attr} in the output
4627 @code{.drectve} section, where @var{attr} is one of @code{READ},
4628 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4629 this and act upon it.
4634 @c man begin SEEALSO dlltool
4635 The Info pages for @file{binutils}.
4642 @cindex ELF file information
4645 @c man title readelf display information about ELF files
4648 @c man begin SYNOPSIS readelf
4649 readelf [@option{-a}|@option{--all}]
4650 [@option{-h}|@option{--file-header}]
4651 [@option{-l}|@option{--program-headers}|@option{--segments}]
4652 [@option{-S}|@option{--section-headers}|@option{--sections}]
4653 [@option{-g}|@option{--section-groups}]
4654 [@option{-t}|@option{--section-details}]
4655 [@option{-e}|@option{--headers}]
4656 [@option{-s}|@option{--syms}|@option{--symbols}]
4657 [@option{--dyn-syms}]
4658 [@option{-n}|@option{--notes}]
4659 [@option{-r}|@option{--relocs}]
4660 [@option{-u}|@option{--unwind}]
4661 [@option{-d}|@option{--dynamic}]
4662 [@option{-V}|@option{--version-info}]
4663 [@option{-A}|@option{--arch-specific}]
4664 [@option{-D}|@option{--use-dynamic}]
4665 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4666 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4667 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4668 [@option{-z}|@option{--decompress}]
4669 [@option{-c}|@option{--archive-index}]
4670 [@option{-w[lLiaprmfFsoRtUuTgAckK]}|
4671 @option{--debug-dump}[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]]
4672 [@option{--dwarf-depth=@var{n}}]
4673 [@option{--dwarf-start=@var{n}}]
4674 [@option{--ctf=}@var{section}]
4675 [@option{--ctf-parent=}@var{section}]
4676 [@option{--ctf-symbols=}@var{section}]
4677 [@option{--ctf-strings=}@var{section}]
4678 [@option{-I}|@option{--histogram}]
4679 [@option{-v}|@option{--version}]
4680 [@option{-W}|@option{--wide}]
4681 [@option{-H}|@option{--help}]
4682 @var{elffile}@dots{}
4686 @c man begin DESCRIPTION readelf
4688 @command{readelf} displays information about one or more ELF format object
4689 files. The options control what particular information to display.
4691 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4692 64-bit ELF files are supported, as are archives containing ELF files.
4694 This program performs a similar function to @command{objdump} but it
4695 goes into more detail and it exists independently of the @sc{bfd}
4696 library, so if there is a bug in @sc{bfd} then readelf will not be
4701 @c man begin OPTIONS readelf
4703 The long and short forms of options, shown here as alternatives, are
4704 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4710 Equivalent to specifying @option{--file-header},
4711 @option{--program-headers}, @option{--sections}, @option{--symbols},
4712 @option{--relocs}, @option{--dynamic}, @option{--notes},
4713 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4714 @option{--section-groups} and @option{--histogram}.
4716 Note - this option does not enable @option{--use-dynamic} itself, so
4717 if that option is not present on the command line then dynamic symbols
4718 and dynamic relocs will not be displayed.
4721 @itemx --file-header
4722 @cindex ELF file header information
4723 Displays the information contained in the ELF header at the start of the
4727 @itemx --program-headers
4729 @cindex ELF program header information
4730 @cindex ELF segment information
4731 Displays the information contained in the file's segment headers, if it
4736 @itemx --section-headers
4737 @cindex ELF section information
4738 Displays the information contained in the file's section headers, if it
4742 @itemx --section-groups
4743 @cindex ELF section group information
4744 Displays the information contained in the file's section groups, if it
4748 @itemx --section-details
4749 @cindex ELF section information
4750 Displays the detailed section information. Implies @option{-S}.
4755 @cindex ELF symbol table information
4756 Displays the entries in symbol table section of the file, if it has one.
4757 If a symbol has version information associated with it then this is
4758 displayed as well. The version string is displayed as a suffix to the
4759 symbol name, preceeded by an @@ character. For example
4760 @samp{foo@@VER_1}. If the version is the default version to be used
4761 when resolving unversioned references to the symbol then it is
4762 displayed as a suffix preceeded by two @@ characters. For example
4763 @samp{foo@@@@VER_2}.
4766 @cindex ELF dynamic symbol table information
4767 Displays the entries in dynamic symbol table section of the file, if it
4768 has one. The output format is the same as the format used by the
4769 @option{--syms} option.
4773 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4778 Displays the contents of the NOTE segments and/or sections, if any.
4782 @cindex ELF reloc information
4783 Displays the contents of the file's relocation section, if it has one.
4787 @cindex unwind information
4788 Displays the contents of the file's unwind section, if it has one. Only
4789 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4790 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
4791 support is not yet implemented for your architecture you could try
4792 dumping the contents of the @var{.eh_frames} section using the
4793 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
4798 @cindex ELF dynamic section information
4799 Displays the contents of the file's dynamic section, if it has one.
4802 @itemx --version-info
4803 @cindex ELF version sections information
4804 Displays the contents of the version sections in the file, it they
4808 @itemx --arch-specific
4809 Displays architecture-specific information in the file, if there
4813 @itemx --use-dynamic
4814 When displaying symbols, this option makes @command{readelf} use the
4815 symbol hash tables in the file's dynamic section, rather than the
4816 symbol table sections.
4818 When displaying relocations, this option makes @command{readelf}
4819 display the dynamic relocations rather than the static relocations.
4821 @item -x <number or name>
4822 @itemx --hex-dump=<number or name>
4823 Displays the contents of the indicated section as a hexadecimal bytes.
4824 A number identifies a particular section by index in the section table;
4825 any other string identifies all sections with that name in the object file.
4827 @item -R <number or name>
4828 @itemx --relocated-dump=<number or name>
4829 Displays the contents of the indicated section as a hexadecimal
4830 bytes. A number identifies a particular section by index in the
4831 section table; any other string identifies all sections with that name
4832 in the object file. The contents of the section will be relocated
4833 before they are displayed.
4835 @item -p <number or name>
4836 @itemx --string-dump=<number or name>
4837 Displays the contents of the indicated section as printable strings.
4838 A number identifies a particular section by index in the section table;
4839 any other string identifies all sections with that name in the object file.
4843 Requests that the section(s) being dumped by @option{x}, @option{R} or
4844 @option{p} options are decompressed before being displayed. If the
4845 section(s) are not compressed then they are displayed as is.
4848 @itemx --archive-index
4849 @cindex Archive file symbol index information
4850 Displays the file symbol index information contained in the header part
4851 of binary archives. Performs the same function as the @option{t}
4852 command to @command{ar}, but without using the BFD library. @xref{ar}.
4854 @item -w[lLiaprmfFsoRtUuTgAckK]
4855 @itemx --debug-dump[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
4856 @include debug.options.texi
4858 @include ctf.options.texi
4859 @item --ctf-symbols=@var{section}
4860 @item --ctf-strings=@var{section}
4861 Specify the name of another section from which the CTF file can inherit
4862 strings and symbols. By default, the @code{.symtab} and its linked
4863 string table are used.
4865 If either of @option{--ctf-symbols} or @option{--ctf-strings} is specified, the
4866 other must be specified as well.
4870 Display a histogram of bucket list lengths when displaying the contents
4871 of the symbol tables.
4875 Display the version number of readelf.
4879 Don't break output lines to fit into 80 columns. By default
4880 @command{readelf} breaks section header and segment listing lines for
4881 64-bit ELF files, so that they fit into 80 columns. This option causes
4882 @command{readelf} to print each section header resp. each segment one a
4883 single line, which is far more readable on terminals wider than 80 columns.
4887 Display the command-line options understood by @command{readelf}.
4894 @c man begin SEEALSO readelf
4895 objdump(1), and the Info entries for @file{binutils}.
4902 @cindex Update ELF header
4905 @c man title elfedit update ELF header and program property of ELF files
4908 @c man begin SYNOPSIS elfedit
4909 elfedit [@option{--input-mach=}@var{machine}]
4910 [@option{--input-type=}@var{type}]
4911 [@option{--input-osabi=}@var{osabi}]
4912 @option{--output-mach=}@var{machine}
4913 @option{--output-type=}@var{type}
4914 @option{--output-osabi=}@var{osabi}
4915 @option{--enable-x86-feature=}@var{feature}
4916 @option{--disable-x86-feature=}@var{feature}
4917 [@option{-v}|@option{--version}]
4918 [@option{-h}|@option{--help}]
4919 @var{elffile}@dots{}
4923 @c man begin DESCRIPTION elfedit
4925 @command{elfedit} updates the ELF header and program property of ELF
4926 files which have the matching ELF machine and file types. The options
4927 control how and which fields in the ELF header and program property
4930 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4931 64-bit ELF files are supported, as are archives containing ELF files.
4934 @c man begin OPTIONS elfedit
4936 The long and short forms of options, shown here as alternatives, are
4937 equivalent. At least one of the @option{--output-mach},
4938 @option{--output-type}, @option{--output-osabi},
4939 @option{--enable-x86-feature} and @option{--disable-x86-feature}
4940 options must be given.
4944 @item --input-mach=@var{machine}
4945 Set the matching input ELF machine type to @var{machine}. If
4946 @option{--input-mach} isn't specified, it will match any ELF
4949 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4950 @var{K1OM} and @var{x86-64}.
4952 @item --output-mach=@var{machine}
4953 Change the ELF machine type in the ELF header to @var{machine}. The
4954 supported ELF machine types are the same as @option{--input-mach}.
4956 @item --input-type=@var{type}
4957 Set the matching input ELF file type to @var{type}. If
4958 @option{--input-type} isn't specified, it will match any ELF file types.
4960 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4962 @item --output-type=@var{type}
4963 Change the ELF file type in the ELF header to @var{type}. The
4964 supported ELF types are the same as @option{--input-type}.
4966 @item --input-osabi=@var{osabi}
4967 Set the matching input ELF file OSABI to @var{osabi}. If
4968 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4970 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4971 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4972 @var{Solaris}, @var{AIX}, @var{Irix},
4973 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4974 @var{NSK}, @var{AROS} and @var{FenixOS}.
4976 @item --output-osabi=@var{osabi}
4977 Change the ELF OSABI in the ELF header to @var{osabi}. The
4978 supported ELF OSABI are the same as @option{--input-osabi}.
4980 @item --enable-x86-feature=@var{feature}
4981 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
4982 ELF files with machine types of @var{i386} or @var{x86-64}. The
4983 supported features are, @var{ibt} and @var{shstk}.
4985 @item --disable-x86-feature=@var{feature}
4986 Clear the @var{feature} bit in program property in @var{exec} or
4987 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
4988 The supported features are the same as @option{--enable-x86-feature}.
4990 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
4991 are available only on hosts with @samp{mmap} support.
4995 Display the version number of @command{elfedit}.
4999 Display the command-line options understood by @command{elfedit}.
5006 @c man begin SEEALSO elfedit
5007 readelf(1), and the Info entries for @file{binutils}.
5011 @node Common Options
5012 @chapter Common Options
5014 The following command-line options are supported by all of the
5015 programs described in this manual.
5017 @c man begin OPTIONS
5019 @include at-file.texi
5023 Display the command-line options supported by the program.
5026 Display the version number of the program.
5028 @c man begin OPTIONS
5032 @node Selecting the Target System
5033 @chapter Selecting the Target System
5035 You can specify two aspects of the target system to the @sc{gnu}
5036 binary file utilities, each in several ways:
5046 In the following summaries, the lists of ways to specify values are in
5047 order of decreasing precedence. The ways listed first override those
5050 The commands to list valid values only list the values for which the
5051 programs you are running were configured. If they were configured with
5052 @option{--enable-targets=all}, the commands list most of the available
5053 values, but a few are left out; not all targets can be configured in at
5054 once because some of them can only be configured @dfn{native} (on hosts
5055 with the same type as the target system).
5058 * Target Selection::
5059 * Architecture Selection::
5062 @node Target Selection
5063 @section Target Selection
5065 A @dfn{target} is an object file format. A given target may be
5066 supported for multiple architectures (@pxref{Architecture Selection}).
5067 A target selection may also have variations for different operating
5068 systems or architectures.
5070 The command to list valid target values is @samp{objdump -i}
5071 (the first column of output contains the relevant information).
5073 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5074 @samp{a.out-sunos-big}.
5076 You can also specify a target using a configuration triplet. This is
5077 the same sort of name that is passed to @file{configure} to specify a
5078 target. When you use a configuration triplet as an argument, it must be
5079 fully canonicalized. You can see the canonical version of a triplet by
5080 running the shell script @file{config.sub} which is included with the
5083 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5084 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5086 @subheading @command{objdump} Target
5092 command-line option: @option{-b} or @option{--target}
5095 environment variable @code{GNUTARGET}
5098 deduced from the input file
5101 @subheading @command{objcopy} and @command{strip} Input Target
5107 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5110 environment variable @code{GNUTARGET}
5113 deduced from the input file
5116 @subheading @command{objcopy} and @command{strip} Output Target
5122 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5125 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5128 environment variable @code{GNUTARGET}
5131 deduced from the input file
5134 @subheading @command{nm}, @command{size}, and @command{strings} Target
5140 command-line option: @option{--target}
5143 environment variable @code{GNUTARGET}
5146 deduced from the input file
5149 @node Architecture Selection
5150 @section Architecture Selection
5152 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5153 to run. Its name may contain a colon, separating the name of the
5154 processor family from the name of the particular @sc{cpu}.
5156 The command to list valid architecture values is @samp{objdump -i} (the
5157 second column contains the relevant information).
5159 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5161 @subheading @command{objdump} Architecture
5167 command-line option: @option{-m} or @option{--architecture}
5170 deduced from the input file
5173 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5179 deduced from the input file
5182 @node Reporting Bugs
5183 @chapter Reporting Bugs
5185 @cindex reporting bugs
5187 Your bug reports play an essential role in making the binary utilities
5190 Reporting a bug may help you by bringing a solution to your problem, or
5191 it may not. But in any case the principal function of a bug report is
5192 to help the entire community by making the next version of the binary
5193 utilities work better. Bug reports are your contribution to their
5196 In order for a bug report to serve its purpose, you must include the
5197 information that enables us to fix the bug.
5200 * Bug Criteria:: Have you found a bug?
5201 * Bug Reporting:: How to report bugs
5205 @section Have You Found a Bug?
5206 @cindex bug criteria
5208 If you are not sure whether you have found a bug, here are some guidelines:
5211 @cindex fatal signal
5214 If a binary utility gets a fatal signal, for any input whatever, that is
5215 a bug. Reliable utilities never crash.
5217 @cindex error on valid input
5219 If a binary utility produces an error message for valid input, that is a
5223 If you are an experienced user of binary utilities, your suggestions for
5224 improvement are welcome in any case.
5228 @section How to Report Bugs
5230 @cindex bugs, reporting
5232 A number of companies and individuals offer support for @sc{gnu}
5233 products. If you obtained the binary utilities from a support
5234 organization, we recommend you contact that organization first.
5236 You can find contact information for many support companies and
5237 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5241 In any event, we also recommend that you send bug reports for the binary
5242 utilities to @value{BUGURL}.
5245 The fundamental principle of reporting bugs usefully is this:
5246 @strong{report all the facts}. If you are not sure whether to state a
5247 fact or leave it out, state it!
5249 Often people omit facts because they think they know what causes the
5250 problem and assume that some details do not matter. Thus, you might
5251 assume that the name of a file you use in an example does not matter.
5252 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5253 a stray memory reference which happens to fetch from the location where
5254 that pathname is stored in memory; perhaps, if the pathname were
5255 different, the contents of that location would fool the utility into
5256 doing the right thing despite the bug. Play it safe and give a
5257 specific, complete example. That is the easiest thing for you to do,
5258 and the most helpful.
5260 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5261 it is new to us. Therefore, always write your bug reports on the assumption
5262 that the bug has not been reported previously.
5264 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5265 bell?'' This cannot help us fix a bug, so it is basically useless. We
5266 respond by asking for enough details to enable us to investigate.
5267 You might as well expedite matters by sending them to begin with.
5269 To enable us to fix the bug, you should include all these things:
5273 The version of the utility. Each utility announces it if you start it
5274 with the @option{--version} argument.
5276 Without this, we will not know whether there is any point in looking for
5277 the bug in the current version of the binary utilities.
5280 Any patches you may have applied to the source, including any patches
5281 made to the @code{BFD} library.
5284 The type of machine you are using, and the operating system name and
5288 What compiler (and its version) was used to compile the utilities---e.g.
5292 The command arguments you gave the utility to observe the bug. To
5293 guarantee you will not omit something important, list them all. A copy
5294 of the Makefile (or the output from make) is sufficient.
5296 If we were to try to guess the arguments, we would probably guess wrong
5297 and then we might not encounter the bug.
5300 A complete input file, or set of input files, that will reproduce the
5301 bug. If the utility is reading an object file or files, then it is
5302 generally most helpful to send the actual object files.
5304 If the source files were produced exclusively using @sc{gnu} programs
5305 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5306 may be OK to send the source files rather than the object files. In
5307 this case, be sure to say exactly what version of @command{gcc}, or
5308 whatever, was used to produce the object files. Also say how
5309 @command{gcc}, or whatever, was configured.
5312 A description of what behavior you observe that you believe is
5313 incorrect. For example, ``It gets a fatal signal.''
5315 Of course, if the bug is that the utility gets a fatal signal, then we
5316 will certainly notice it. But if the bug is incorrect output, we might
5317 not notice unless it is glaringly wrong. You might as well not give us
5318 a chance to make a mistake.
5320 Even if the problem you experience is a fatal signal, you should still
5321 say so explicitly. Suppose something strange is going on, such as your
5322 copy of the utility is out of sync, or you have encountered a bug in
5323 the C library on your system. (This has happened!) Your copy might
5324 crash and ours would not. If you told us to expect a crash, then when
5325 ours fails to crash, we would know that the bug was not happening for
5326 us. If you had not told us to expect a crash, then we would not be able
5327 to draw any conclusion from our observations.
5330 If you wish to suggest changes to the source, send us context diffs, as
5331 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5332 option. Always send diffs from the old file to the new file. If you
5333 wish to discuss something in the @command{ld} source, refer to it by
5334 context, not by line number.
5336 The line numbers in our development sources will not match those in your
5337 sources. Your line numbers would convey no useful information to us.
5340 Here are some things that are not necessary:
5344 A description of the envelope of the bug.
5346 Often people who encounter a bug spend a lot of time investigating
5347 which changes to the input file will make the bug go away and which
5348 changes will not affect it.
5350 This is often time consuming and not very useful, because the way we
5351 will find the bug is by running a single example under the debugger
5352 with breakpoints, not by pure deduction from a series of examples.
5353 We recommend that you save your time for something else.
5355 Of course, if you can find a simpler example to report @emph{instead}
5356 of the original one, that is a convenience for us. Errors in the
5357 output will be easier to spot, running under the debugger will take
5358 less time, and so on.
5360 However, simplification is not vital; if you do not want to do this,
5361 report the bug anyway and send us the entire test case you used.
5364 A patch for the bug.
5366 A patch for the bug does help us if it is a good one. But do not omit
5367 the necessary information, such as the test case, on the assumption that
5368 a patch is all we need. We might see problems with your patch and decide
5369 to fix the problem another way, or we might not understand it at all.
5371 Sometimes with programs as complicated as the binary utilities it is
5372 very hard to construct an example that will make the program follow a
5373 certain path through the code. If you do not send us the example, we
5374 will not be able to construct one, so we will not be able to verify that
5377 And if we cannot understand what bug you are trying to fix, or why your
5378 patch should be an improvement, we will not install it. A test case will
5379 help us to understand.
5382 A guess about what the bug is or what it depends on.
5384 Such guesses are usually wrong. Even we cannot guess right about such
5385 things without first using the debugger to find the facts.
5388 @node GNU Free Documentation License
5389 @appendix GNU Free Documentation License
5393 @node Binutils Index
5394 @unnumbered Binutils Index