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.
393 A number of modifiers (@var{mod}) may immediately follow the @var{p}
394 keyletter, to specify variations on an operation's behavior:
398 @cindex relative placement in archive
399 Add new files @emph{after} an existing member of the
400 archive. If you use the modifier @samp{a}, the name of an existing archive
401 member must be present as the @var{relpos} argument, before the
402 @var{archive} specification.
405 Add new files @emph{before} an existing member of the
406 archive. If you use the modifier @samp{b}, the name of an existing archive
407 member must be present as the @var{relpos} argument, before the
408 @var{archive} specification. (same as @samp{i}).
411 @cindex creating archives
412 @emph{Create} the archive. The specified @var{archive} is always
413 created if it did not exist, when you request an update. But a warning is
414 issued unless you specify in advance that you expect to create it, by
418 @cindex deterministic archives
419 @kindex --enable-deterministic-archives
420 Operate in @emph{deterministic} mode. When adding files and the archive
421 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
422 for all files. When this option is used, if @command{ar} is used with
423 identical options and identical input files, multiple runs will create
424 identical output files regardless of the input files' owners, groups,
425 file modes, or modification times.
427 If @file{binutils} was configured with
428 @option{--enable-deterministic-archives}, then this mode is on by default.
429 It can be disabled with the @samp{U} modifier, below.
432 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
433 names of any length. This will cause it to create archives which are
434 not compatible with the native @command{ar} program on some systems. If
435 this is a concern, the @samp{f} modifier may be used to truncate file
436 names when putting them in the archive.
439 Insert new files @emph{before} an existing member of the
440 archive. If you use the modifier @samp{i}, the name of an existing archive
441 member must be present as the @var{relpos} argument, before the
442 @var{archive} specification. (same as @samp{b}).
445 This modifier is accepted but not used.
446 @c whaffor ar l modifier??? presumably compat; with
447 @c what???---doc@@cygnus.com, 25jan91
450 Uses the @var{count} parameter. This is used if there are multiple
451 entries in the archive with the same name. Extract or delete instance
452 @var{count} of the given name from the archive.
455 @cindex dates in archive
456 Preserve the @emph{original} dates of members when extracting them. If
457 you do not specify this modifier, files extracted from the archive
458 are stamped with the time of extraction.
461 @cindex offsets of files
462 Display member offsets inside the archive. Use together with the @samp{t}
466 Use the full path name when matching names in the archive. @sc{gnu}
467 @command{ar} can not create an archive with a full path name (such archives
468 are not POSIX compliant), but other archive creators can. This option
469 will cause @sc{gnu} @command{ar} to match file names using a complete path
470 name, which can be convenient when extracting a single file from an
471 archive created by another tool.
474 @cindex writing archive index
475 Write an object-file index into the archive, or update an existing one,
476 even if no other change is made to the archive. You may use this modifier
477 flag either with any operation, or alone. Running @samp{ar s} on an
478 archive is equivalent to running @samp{ranlib} on it.
481 @cindex not writing archive index
482 Do not generate an archive symbol table. This can speed up building a
483 large library in several steps. The resulting archive can not be used
484 with the linker. In order to build a symbol table, you must omit the
485 @samp{S} modifier on the last execution of @samp{ar}, or you must run
486 @samp{ranlib} on the archive.
489 @cindex creating thin archive
490 Make the specified @var{archive} a @emph{thin} archive. If it already
491 exists and is a regular archive, the existing members must be present
492 in the same directory as @var{archive}.
495 @cindex updating an archive
496 Normally, @samp{ar r}@dots{} inserts all files
497 listed into the archive. If you would like to insert @emph{only} those
498 of the files you list that are newer than existing members of the same
499 names, use this modifier. The @samp{u} modifier is allowed only for the
500 operation @samp{r} (replace). In particular, the combination @samp{qu} is
501 not allowed, since checking the timestamps would lose any speed
502 advantage from the operation @samp{q}.
505 @cindex deterministic archives
506 @kindex --enable-deterministic-archives
507 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
508 of the @samp{D} modifier, above: added files and the archive index will
509 get their actual UID, GID, timestamp, and file mode values.
511 This is the default unless @file{binutils} was configured with
512 @option{--enable-deterministic-archives}.
515 This modifier requests the @emph{verbose} version of an operation. Many
516 operations display additional information, such as filenames processed,
517 when the modifier @samp{v} is appended.
520 This modifier shows the version number of @command{ar}.
523 The @command{ar} program also supports some command-line options which
524 are neither modifiers nor actions, but which do change its behaviour
529 Displays the list of command-line options supported by @command{ar}
533 Displays the version information of @command{ar} and then exits.
536 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
537 compatibility with AIX. The behaviour produced by this option is the
538 default for @sc{gnu} @command{ar}. @command{ar} does not support any
539 of the other @samp{-X} options; in particular, it does not support
540 @option{-X32} which is the default for AIX @command{ar}.
542 @item --plugin @var{name}
544 The optional command-line switch @option{--plugin @var{name}} causes
545 @command{ar} to load the plugin called @var{name} which adds support
546 for more file formats, including object files with link-time
547 optimization information.
549 This option is only available if the toolchain has been built with
550 plugin support enabled.
552 If @option{--plugin} is not provided, but plugin support has been
553 enabled then @command{ar} iterates over the files in
554 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
555 plugin that claims the object in question is used.
557 Please note that this plugin search directory is @emph{not} the one
558 used by @command{ld}'s @option{-plugin} option. In order to make
559 @command{ar} use the linker plugin it must be copied into the
560 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
561 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
562 based compilations it is called @file{LLVMgold.so}. The GCC plugin
563 is always backwards compatible with earlier versions, so it is
564 sufficient to just copy the newest one.
566 @item --target @var{target}
567 The optional command-line switch @option{--target @var{bfdname}}
568 specifies that the archive members are in an object code format
569 different from your system's default format. See
570 @xref{Target Selection}, for more information.
575 @c man begin SEEALSO ar
576 nm(1), ranlib(1), and the Info entries for @file{binutils}.
581 @section Controlling @command{ar} with a Script
584 ar -M [ <@var{script} ]
587 @cindex MRI compatibility, @command{ar}
588 @cindex scripts, @command{ar}
589 If you use the single command-line option @samp{-M} with @command{ar}, you
590 can control its operation with a rudimentary command language. This
591 form of @command{ar} operates interactively if standard input is coming
592 directly from a terminal. During interactive use, @command{ar} prompts for
593 input (the prompt is @samp{AR >}), and continues executing even after
594 errors. If you redirect standard input to a script file, no prompts are
595 issued, and @command{ar} abandons execution (with a nonzero exit code)
598 The @command{ar} command language is @emph{not} designed to be equivalent
599 to the command-line options; in fact, it provides somewhat less control
600 over archives. The only purpose of the command language is to ease the
601 transition to @sc{gnu} @command{ar} for developers who already have scripts
602 written for the MRI ``librarian'' program.
604 The syntax for the @command{ar} command language is straightforward:
607 commands are recognized in upper or lower case; for example, @code{LIST}
608 is the same as @code{list}. In the following descriptions, commands are
609 shown in upper case for clarity.
612 a single command may appear on each line; it is the first word on the
616 empty lines are allowed, and have no effect.
619 comments are allowed; text after either of the characters @samp{*}
620 or @samp{;} is ignored.
623 Whenever you use a list of names as part of the argument to an @command{ar}
624 command, you can separate the individual names with either commas or
625 blanks. Commas are shown in the explanations below, for clarity.
628 @samp{+} is used as a line continuation character; if @samp{+} appears
629 at the end of a line, the text on the following line is considered part
630 of the current command.
633 Here are the commands you can use in @command{ar} scripts, or when using
634 @command{ar} interactively. Three of them have special significance:
636 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
637 a temporary file required for most of the other commands.
639 @code{SAVE} commits the changes so far specified by the script. Prior
640 to @code{SAVE}, commands affect only the temporary copy of the current
644 @item ADDLIB @var{archive}
645 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
646 Add all the contents of @var{archive} (or, if specified, each named
647 @var{module} from @var{archive}) to the current archive.
649 Requires prior use of @code{OPEN} or @code{CREATE}.
651 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
652 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
653 @c else like "ar q..."
654 Add each named @var{member} as a module in the current archive.
656 Requires prior use of @code{OPEN} or @code{CREATE}.
659 Discard the contents of the current archive, canceling the effect of
660 any operations since the last @code{SAVE}. May be executed (with no
661 effect) even if no current archive is specified.
663 @item CREATE @var{archive}
664 Creates an archive, and makes it the current archive (required for many
665 other commands). The new archive is created with a temporary name; it
666 is not actually saved as @var{archive} until you use @code{SAVE}.
667 You can overwrite existing archives; similarly, the contents of any
668 existing file named @var{archive} will not be destroyed until @code{SAVE}.
670 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
671 Delete each listed @var{module} from the current archive; equivalent to
672 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
674 Requires prior use of @code{OPEN} or @code{CREATE}.
676 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
677 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
678 List each named @var{module} present in @var{archive}. The separate
679 command @code{VERBOSE} specifies the form of the output: when verbose
680 output is off, output is like that of @samp{ar -t @var{archive}
681 @var{module}@dots{}}. When verbose output is on, the listing is like
682 @samp{ar -tv @var{archive} @var{module}@dots{}}.
684 Output normally goes to the standard output stream; however, if you
685 specify @var{outputfile} as a final argument, @command{ar} directs the
689 Exit from @command{ar}, with a @code{0} exit code to indicate successful
690 completion. This command does not save the output file; if you have
691 changed the current archive since the last @code{SAVE} command, those
694 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
695 Extract each named @var{module} from the current archive, writing them
696 into the current directory as separate files. Equivalent to @samp{ar -x
697 @var{archive} @var{module}@dots{}}.
699 Requires prior use of @code{OPEN} or @code{CREATE}.
702 @c FIXME Tokens but no commands???
709 Display full contents of the current archive, in ``verbose'' style
710 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
711 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
712 enhancement, rather than present for MRI compatibility.)
714 Requires prior use of @code{OPEN} or @code{CREATE}.
716 @item OPEN @var{archive}
717 Opens an existing archive for use as the current archive (required for
718 many other commands). Any changes as the result of subsequent commands
719 will not actually affect @var{archive} until you next use @code{SAVE}.
721 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
722 In the current archive, replace each existing @var{module} (named in
723 the @code{REPLACE} arguments) from files in the current working directory.
724 To execute this command without errors, both the file, and the module in
725 the current archive, must exist.
727 Requires prior use of @code{OPEN} or @code{CREATE}.
730 Toggle an internal flag governing the output from @code{DIRECTORY}.
731 When the flag is on, @code{DIRECTORY} output matches output from
732 @samp{ar -tv }@dots{}.
735 Commit your changes to the current archive, and actually save it as a
736 file with the name specified in the last @code{CREATE} or @code{OPEN}
739 Requires prior use of @code{OPEN} or @code{CREATE}.
748 The @sc{gnu} linker @command{ld} is now described in a separate manual.
749 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
757 @c man title nm list symbols from object files
760 @c man begin SYNOPSIS nm
761 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
762 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
763 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
764 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
765 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
766 [@option{-n}|@option{-v}|@option{--numeric-sort}]
767 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
768 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
769 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
770 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
771 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
772 [@option{--plugin} @var{name}]
773 [@option{--no-recurse-limit}|@option{--recurse-limit}]]
774 [@option{--size-sort}] [@option{--special-syms}]
775 [@option{--synthetic}] [@option{--with-symbol-versions}] [@option{--target=}@var{bfdname}]
776 [@var{objfile}@dots{}]
780 @c man begin DESCRIPTION nm
781 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
782 If no object files are listed as arguments, @command{nm} assumes the file
785 For each symbol, @command{nm} shows:
789 The symbol value, in the radix selected by options (see below), or
790 hexadecimal by default.
793 The symbol type. At least the following types are used; others are, as
794 well, depending on the object file format. If lowercase, the symbol is
795 usually local; if uppercase, the symbol is global (external). There
796 are however a few lowercase symbols that are shown for special global
797 symbols (@code{u}, @code{v} and @code{w}).
799 @c Some more detail on exactly what these symbol types are used for
803 The symbol's value is absolute, and will not be changed by further
808 The symbol is in the BSS data section. This section typically
809 contains zero-initialized or uninitialized data, although the exact
810 behavior is system dependent.
813 The symbol is common. Common symbols are uninitialized data. When
814 linking, multiple common symbols may appear with the same name. If the
815 symbol is defined anywhere, the common symbols are treated as undefined
818 For more details on common symbols, see the discussion of
819 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
824 The symbol is in the initialized data section.
828 The symbol is in an initialized data section for small objects. Some
829 object file formats permit more efficient access to small data objects,
830 such as a global int variable as opposed to a large global array.
833 For PE format files this indicates that the symbol is in a section
834 specific to the implementation of DLLs. For ELF format files this
835 indicates that the symbol is an indirect function. This is a GNU
836 extension to the standard set of ELF symbol types. It indicates a
837 symbol which if referenced by a relocation does not evaluate to its
838 address, but instead must be invoked at runtime. The runtime
839 execution will then return the value to be used in the relocation.
842 The symbol is an indirect reference to another symbol.
845 The symbol is a debugging symbol.
848 The symbols is in a stack unwind section.
852 The symbol is in a read only data section.
856 The symbol is in an uninitialized or zero-initialized data section
861 The symbol is in the text (code) section.
864 The symbol is undefined.
867 The symbol is a unique global symbol. This is a GNU extension to the
868 standard set of ELF symbol bindings. For such a symbol the dynamic linker
869 will make sure that in the entire process there is just one symbol with
870 this name and type in use.
874 The symbol is a weak object. When a weak defined symbol is linked with
875 a normal defined symbol, the normal defined symbol is used with no error.
876 When a weak undefined symbol is linked and the symbol is not defined,
877 the value of the weak symbol becomes zero with no error. On some
878 systems, uppercase indicates that a default value has been specified.
882 The symbol is a weak symbol that has not been specifically tagged as a
883 weak object symbol. When a weak defined symbol is linked with a normal
884 defined symbol, the normal defined symbol is used with no error.
885 When a weak undefined symbol is linked and the symbol is not defined,
886 the value of the symbol is determined in a system-specific manner without
887 error. On some systems, uppercase indicates that a default value has been
891 The symbol is a stabs symbol in an a.out object file. In this case, the
892 next values printed are the stabs other field, the stabs desc field, and
893 the stab type. Stabs symbols are used to hold debugging information.
896 The symbol type is unknown, or object file format specific.
905 @c man begin OPTIONS nm
906 The long and short forms of options, shown here as alternatives, are
912 @itemx --print-file-name
913 @cindex input file name
915 @cindex source file name
916 Precede each symbol by the name of the input file (or archive member)
917 in which it was found, rather than identifying the input file once only,
918 before all of its symbols.
922 @cindex debugging symbols
923 Display all symbols, even debugger-only symbols; normally these are not
927 @cindex @command{nm} format
928 @cindex @command{nm} compatibility
929 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
932 @itemx --demangle[=@var{style}]
933 @cindex demangling in nm
934 Decode (@dfn{demangle}) low-level symbol names into user-level names.
935 Besides removing any initial underscore prepended by the system, this
936 makes C++ function names readable. Different compilers have different
937 mangling styles. The optional demangling style argument can be used to
938 choose an appropriate demangling style for your compiler. @xref{c++filt},
939 for more information on demangling.
942 Do not demangle low-level symbol names. This is the default.
944 @item --recurse-limit
945 @itemx --no-recurse-limit
946 @itemx --recursion-limit
947 @itemx --no-recursion-limit
948 Enables or disables a limit on the amount of recursion performed
949 whilst demangling strings. Since the name mangling formats allow for
950 an inifinite level of recursion it is possible to create strings whose
951 decoding will exhaust the amount of stack space available on the host
952 machine, triggering a memory fault. The limit tries to prevent this
953 from happening by restricting recursion to 2048 levels of nesting.
955 The default is for this limit to be enabled, but disabling it may be
956 necessary in order to demangle truly complicated names. Note however
957 that if the recursion limit is disabled then stack exhaustion is
958 possible and any bug reports about such an event will be rejected.
962 @cindex dynamic symbols
963 Display the dynamic symbols rather than the normal symbols. This is
964 only meaningful for dynamic objects, such as certain types of shared
967 @item -f @var{format}
968 @itemx --format=@var{format}
969 @cindex @command{nm} format
970 @cindex @command{nm} compatibility
971 Use the output format @var{format}, which can be @code{bsd},
972 @code{sysv}, or @code{posix}. The default is @code{bsd}.
973 Only the first character of @var{format} is significant; it can be
974 either upper or lower case.
978 @cindex external symbols
979 Display only external symbols.
983 Show a summary of the options to @command{nm} and exit.
986 @itemx --line-numbers
987 @cindex symbol line numbers
988 For each symbol, use debugging information to try to find a filename and
989 line number. For a defined symbol, look for the line number of the
990 address of the symbol. For an undefined symbol, look for the line
991 number of a relocation entry which refers to the symbol. If line number
992 information can be found, print it after the other symbol information.
995 @cindex objdump inlines
996 When option @option{-l} is active, if the address belongs to a
997 function that was inlined, then this option causes the source
998 information for all enclosing scopes back to the first non-inlined
999 function to be printed as well. For example, if @code{main} inlines
1000 @code{callee1} which inlines @code{callee2}, and address is from
1001 @code{callee2}, the source information for @code{callee1} and @code{main}
1002 will also be printed.
1006 @itemx --numeric-sort
1007 Sort symbols numerically by their addresses, rather than alphabetically
1012 @cindex sorting symbols
1013 Do not bother to sort the symbols in any order; print them in the order
1017 @itemx --portability
1018 Use the POSIX.2 standard output format instead of the default format.
1019 Equivalent to @samp{-f posix}.
1022 @itemx --reverse-sort
1023 Reverse the order of the sort (whether numeric or alphabetic); let the
1028 Print both value and size of defined symbols for the @code{bsd} output style.
1029 This option has no effect for object formats that do not record symbol
1030 sizes, unless @samp{--size-sort} is also used in which case a
1031 calculated size is displayed.
1034 @itemx --print-armap
1035 @cindex symbol index, listing
1036 When listing symbols from archive members, include the index: a mapping
1037 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1038 contain definitions for which names.
1040 @item -t @var{radix}
1041 @itemx --radix=@var{radix}
1042 Use @var{radix} as the radix for printing the symbol values. It must be
1043 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1046 @itemx --undefined-only
1047 @cindex external symbols
1048 @cindex undefined symbols
1049 Display only undefined symbols (those external to each object file).
1053 Show the version number of @command{nm} and exit.
1056 This option is ignored for compatibility with the AIX version of
1057 @command{nm}. It takes one parameter which must be the string
1058 @option{32_64}. The default mode of AIX @command{nm} corresponds
1059 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1061 @item --defined-only
1062 @cindex external symbols
1063 @cindex undefined symbols
1064 Display only defined symbols for each object file.
1066 @item --plugin @var{name}
1068 Load the plugin called @var{name} to add support for extra target
1069 types. This option is only available if the toolchain has been built
1070 with plugin support enabled.
1072 If @option{--plugin} is not provided, but plugin support has been
1073 enabled then @command{nm} iterates over the files in
1074 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1075 plugin that claims the object in question is used.
1077 Please note that this plugin search directory is @emph{not} the one
1078 used by @command{ld}'s @option{-plugin} option. In order to make
1079 @command{nm} use the linker plugin it must be copied into the
1080 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1081 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1082 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1083 is always backwards compatible with earlier versions, so it is
1084 sufficient to just copy the newest one.
1087 Sort symbols by size. For ELF objects symbol sizes are read from the
1088 ELF, for other object types the symbol sizes are computed as the
1089 difference between the value of the symbol and the value of the symbol
1090 with the next higher value. If the @code{bsd} output format is used
1091 the size of the symbol is printed, rather than the value, and
1092 @samp{-S} must be used in order both size and value to be printed.
1094 @item --special-syms
1095 Display symbols which have a target-specific special meaning. These
1096 symbols are usually used by the target for some special processing and
1097 are not normally helpful when included in the normal symbol lists.
1098 For example for ARM targets this option would skip the mapping symbols
1099 used to mark transitions between ARM code, THUMB code and data.
1102 Include synthetic symbols in the output. These are special symbols
1103 created by the linker for various purposes. They are not shown by
1104 default since they are not part of the binary's original source code.
1106 @item --with-symbol-versions
1107 Enables the display of symbol version information if any exists. The
1108 version string is displayed as a suffix to the symbol name, preceeded by
1109 an @@ character. For example @samp{foo@@VER_1}. If the version is
1110 the default version to be used when resolving unversioned references
1111 to the symbol then it is displayed as a suffix preceeded by two @@
1112 characters. For example @samp{foo@@@@VER_2}.
1114 @item --target=@var{bfdname}
1115 @cindex object code format
1116 Specify an object code format other than your system's default format.
1117 @xref{Target Selection}, for more information.
1124 @c man begin SEEALSO nm
1125 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1132 @c man title objcopy copy and translate object files
1135 @c man begin SYNOPSIS objcopy
1136 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1137 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1138 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1139 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1140 [@option{-S}|@option{--strip-all}]
1141 [@option{-g}|@option{--strip-debug}]
1142 [@option{--strip-unneeded}]
1143 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1144 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1145 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1146 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1147 [@option{--localize-hidden}]
1148 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1149 [@option{--globalize-symbol=}@var{symbolname}]
1150 [@option{--globalize-symbols=}@var{filename}]
1151 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1152 [@option{-w}|@option{--wildcard}]
1153 [@option{-x}|@option{--discard-all}]
1154 [@option{-X}|@option{--discard-locals}]
1155 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1156 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1157 [@option{--interleave-width=}@var{width}]
1158 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1159 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1160 [@option{--remove-relocations=}@var{sectionpattern}]
1161 [@option{-p}|@option{--preserve-dates}]
1162 [@option{-D}|@option{--enable-deterministic-archives}]
1163 [@option{-U}|@option{--disable-deterministic-archives}]
1164 [@option{--debugging}]
1165 [@option{--gap-fill=}@var{val}]
1166 [@option{--pad-to=}@var{address}]
1167 [@option{--set-start=}@var{val}]
1168 [@option{--adjust-start=}@var{incr}]
1169 [@option{--change-addresses=}@var{incr}]
1170 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1171 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1172 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1173 [@option{--change-warnings}] [@option{--no-change-warnings}]
1174 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1175 [@option{--add-section} @var{sectionname}=@var{filename}]
1176 [@option{--dump-section} @var{sectionname}=@var{filename}]
1177 [@option{--update-section} @var{sectionname}=@var{filename}]
1178 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1179 [@option{--long-section-names} @{enable,disable,keep@}]
1180 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1181 [@option{--reverse-bytes=}@var{num}]
1182 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1183 [@option{--redefine-sym} @var{old}=@var{new}]
1184 [@option{--redefine-syms=}@var{filename}]
1186 [@option{--keep-symbols=}@var{filename}]
1187 [@option{--strip-symbols=}@var{filename}]
1188 [@option{--strip-unneeded-symbols=}@var{filename}]
1189 [@option{--keep-global-symbols=}@var{filename}]
1190 [@option{--localize-symbols=}@var{filename}]
1191 [@option{--weaken-symbols=}@var{filename}]
1192 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]]
1193 [@option{--alt-machine-code=}@var{index}]
1194 [@option{--prefix-symbols=}@var{string}]
1195 [@option{--prefix-sections=}@var{string}]
1196 [@option{--prefix-alloc-sections=}@var{string}]
1197 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1198 [@option{--keep-file-symbols}]
1199 [@option{--only-keep-debug}]
1200 [@option{--strip-dwo}]
1201 [@option{--extract-dwo}]
1202 [@option{--extract-symbol}]
1203 [@option{--writable-text}]
1204 [@option{--readonly-text}]
1207 [@option{--file-alignment=}@var{num}]
1208 [@option{--heap=}@var{size}]
1209 [@option{--image-base=}@var{address}]
1210 [@option{--section-alignment=}@var{num}]
1211 [@option{--stack=}@var{size}]
1212 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1213 [@option{--compress-debug-sections}]
1214 [@option{--decompress-debug-sections}]
1215 [@option{--elf-stt-common=@var{val}}]
1216 [@option{--merge-notes}]
1217 [@option{--no-merge-notes}]
1218 [@option{--verilog-data-width=@var{val}}]
1219 [@option{-v}|@option{--verbose}]
1220 [@option{-V}|@option{--version}]
1221 [@option{--help}] [@option{--info}]
1222 @var{infile} [@var{outfile}]
1226 @c man begin DESCRIPTION objcopy
1227 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1228 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1229 read and write the object files. It can write the destination object
1230 file in a format different from that of the source object file. The
1231 exact behavior of @command{objcopy} is controlled by command-line options.
1232 Note that @command{objcopy} should be able to copy a fully linked file
1233 between any two formats. However, copying a relocatable object file
1234 between any two formats may not work as expected.
1236 @command{objcopy} creates temporary files to do its translations and
1237 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1238 translation work; it has access to all the formats described in @sc{bfd}
1239 and thus is able to recognize most formats without being told
1240 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1242 @command{objcopy} can be used to generate S-records by using an output
1243 target of @samp{srec} (e.g., use @samp{-O srec}).
1245 @command{objcopy} can be used to generate a raw binary file by using an
1246 output target of @samp{binary} (e.g., use @option{-O binary}). When
1247 @command{objcopy} generates a raw binary file, it will essentially produce
1248 a memory dump of the contents of the input object file. All symbols and
1249 relocation information will be discarded. The memory dump will start at
1250 the load address of the lowest section copied into the output file.
1252 When generating an S-record or a raw binary file, it may be helpful to
1253 use @option{-S} to remove sections containing debugging information. In
1254 some cases @option{-R} will be useful to remove sections which contain
1255 information that is not needed by the binary file.
1257 Note---@command{objcopy} is not able to change the endianness of its input
1258 files. If the input format has an endianness (some formats do not),
1259 @command{objcopy} can only copy the inputs into file formats that have the
1260 same endianness or which have no endianness (e.g., @samp{srec}).
1261 (However, see the @option{--reverse-bytes} option.)
1265 @c man begin OPTIONS objcopy
1269 @itemx @var{outfile}
1270 The input and output files, respectively.
1271 If you do not specify @var{outfile}, @command{objcopy} creates a
1272 temporary file and destructively renames the result with
1273 the name of @var{infile}.
1275 @item -I @var{bfdname}
1276 @itemx --input-target=@var{bfdname}
1277 Consider the source file's object format to be @var{bfdname}, rather than
1278 attempting to deduce it. @xref{Target Selection}, for more information.
1280 @item -O @var{bfdname}
1281 @itemx --output-target=@var{bfdname}
1282 Write the output file using the object format @var{bfdname}.
1283 @xref{Target Selection}, for more information.
1285 @item -F @var{bfdname}
1286 @itemx --target=@var{bfdname}
1287 Use @var{bfdname} as the object format for both the input and the output
1288 file; i.e., simply transfer data from source to destination with no
1289 translation. @xref{Target Selection}, for more information.
1291 @item -B @var{bfdarch}
1292 @itemx --binary-architecture=@var{bfdarch}
1293 Useful when transforming a architecture-less input file into an object file.
1294 In this case the output architecture can be set to @var{bfdarch}. This
1295 option will be ignored if the input file has a known @var{bfdarch}. You
1296 can access this binary data inside a program by referencing the special
1297 symbols that are created by the conversion process. These symbols are
1298 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1299 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1300 an object file and then access it in your code using these symbols.
1302 @item -j @var{sectionpattern}
1303 @itemx --only-section=@var{sectionpattern}
1304 Copy only the indicated sections from the input file to the output file.
1305 This option may be given more than once. Note that using this option
1306 inappropriately may make the output file unusable. Wildcard
1307 characters are accepted in @var{sectionpattern}.
1309 If the first character of @var{sectionpattern} is the exclamation
1310 point (!) then matching sections will not be copied, even if earlier
1311 use of @option{--only-section} on the same command line would
1312 otherwise copy it. For example:
1315 --only-section=.text.* --only-section=!.text.foo
1318 will copy all sectinos maching '.text.*' but not the section
1321 @item -R @var{sectionpattern}
1322 @itemx --remove-section=@var{sectionpattern}
1323 Remove any section matching @var{sectionpattern} from the output file.
1324 This option may be given more than once. Note that using this option
1325 inappropriately may make the output file unusable. Wildcard
1326 characters are accepted in @var{sectionpattern}. Using both the
1327 @option{-j} and @option{-R} options together results in undefined
1330 If the first character of @var{sectionpattern} is the exclamation
1331 point (!) then matching sections will not be removed even if an
1332 earlier use of @option{--remove-section} on the same command line
1333 would otherwise remove it. For example:
1336 --remove-section=.text.* --remove-section=!.text.foo
1339 will remove all sections matching the pattern '.text.*', but will not
1340 remove the section '.text.foo'.
1342 @item --remove-relocations=@var{sectionpattern}
1343 Remove non-dynamic relocations from the output file for any section
1344 matching @var{sectionpattern}. This option may be given more than
1345 once. Note that using this option inappropriately may make the output
1346 file unusable, and attempting to remove a dynamic relocation section
1347 such as @samp{.rela.plt} from an executable or shared library with
1348 @option{--remove-relocations=.plt} will not work. Wildcard characters
1349 are accepted in @var{sectionpattern}.
1353 --remove-relocations=.text.*
1356 will remove the relocations for all sections matching the pattern
1359 If the first character of @var{sectionpattern} is the exclamation
1360 point (!) then matching sections will not have their relocation
1361 removed even if an earlier use of @option{--remove-relocations} on the
1362 same command line would otherwise cause the relocations to be removed.
1366 --remove-relocations=.text.* --remove-relocations=!.text.foo
1369 will remove all relocations for sections matching the pattern
1370 '.text.*', but will not remove relocations for the section
1375 Do not copy relocation and symbol information from the source file.
1378 @itemx --strip-debug
1379 Do not copy debugging symbols or sections from the source file.
1381 @item --strip-unneeded
1382 Strip all symbols that are not needed for relocation processing.
1384 @item -K @var{symbolname}
1385 @itemx --keep-symbol=@var{symbolname}
1386 When stripping symbols, keep symbol @var{symbolname} even if it would
1387 normally be stripped. This option may be given more than once.
1389 @item -N @var{symbolname}
1390 @itemx --strip-symbol=@var{symbolname}
1391 Do not copy symbol @var{symbolname} from the source file. This option
1392 may be given more than once.
1394 @item --strip-unneeded-symbol=@var{symbolname}
1395 Do not copy symbol @var{symbolname} from the source file unless it is needed
1396 by a relocation. This option may be given more than once.
1398 @item -G @var{symbolname}
1399 @itemx --keep-global-symbol=@var{symbolname}
1400 Keep only symbol @var{symbolname} global. Make all other symbols local
1401 to the file, so that they are not visible externally. This option may
1402 be given more than once. Note: this option cannot be used in
1403 conjunction with the @option{--globalize-symbol} or
1404 @option{--globalize-symbols} options.
1406 @item --localize-hidden
1407 In an ELF object, mark all symbols that have hidden or internal visibility
1408 as local. This option applies on top of symbol-specific localization options
1409 such as @option{-L}.
1411 @item -L @var{symbolname}
1412 @itemx --localize-symbol=@var{symbolname}
1413 Convert a global or weak symbol called @var{symbolname} into a local
1414 symbol, so that it is not visible externally. This option may be
1415 given more than once. Note - unique symbols are not converted.
1417 @item -W @var{symbolname}
1418 @itemx --weaken-symbol=@var{symbolname}
1419 Make symbol @var{symbolname} weak. This option may be given more than once.
1421 @item --globalize-symbol=@var{symbolname}
1422 Give symbol @var{symbolname} global scoping so that it is visible
1423 outside of the file in which it is defined. This option may be given
1424 more than once. Note: this option cannot be used in conjunction with
1425 the @option{-G} or @option{--keep-global-symbol} options.
1429 Permit regular expressions in @var{symbolname}s used in other command
1430 line options. The question mark (?), asterisk (*), backslash (\) and
1431 square brackets ([]) operators can be used anywhere in the symbol
1432 name. If the first character of the symbol name is the exclamation
1433 point (!) then the sense of the switch is reversed for that symbol.
1440 would cause objcopy to weaken all symbols that start with ``fo''
1441 except for the symbol ``foo''.
1444 @itemx --discard-all
1445 Do not copy non-global symbols from the source file.
1446 @c FIXME any reason to prefer "non-global" to "local" here?
1449 @itemx --discard-locals
1450 Do not copy compiler-generated local symbols.
1451 (These usually start with @samp{L} or @samp{.}.)
1454 @itemx --byte=@var{byte}
1455 If interleaving has been enabled via the @option{--interleave} option
1456 then start the range of bytes to keep at the @var{byte}th byte.
1457 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1458 @var{breadth} is the value given by the @option{--interleave} option.
1460 @item -i [@var{breadth}]
1461 @itemx --interleave[=@var{breadth}]
1462 Only copy a range out of every @var{breadth} bytes. (Header data is
1463 not affected). Select which byte in the range begins the copy with
1464 the @option{--byte} option. Select the width of the range with the
1465 @option{--interleave-width} option.
1467 This option is useful for creating files to program @sc{rom}. It is
1468 typically used with an @code{srec} output target. Note that
1469 @command{objcopy} will complain if you do not specify the
1470 @option{--byte} option as well.
1472 The default interleave breadth is 4, so with @option{--byte} set to 0,
1473 @command{objcopy} would copy the first byte out of every four bytes
1474 from the input to the output.
1476 @item --interleave-width=@var{width}
1477 When used with the @option{--interleave} option, copy @var{width}
1478 bytes at a time. The start of the range of bytes to be copied is set
1479 by the @option{--byte} option, and the extent of the range is set with
1480 the @option{--interleave} option.
1482 The default value for this option is 1. The value of @var{width} plus
1483 the @var{byte} value set by the @option{--byte} option must not exceed
1484 the interleave breadth set by the @option{--interleave} option.
1486 This option can be used to create images for two 16-bit flashes interleaved
1487 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1488 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1489 commands. If the input was '12345678' then the outputs would be
1490 '1256' and '3478' respectively.
1493 @itemx --preserve-dates
1494 Set the access and modification dates of the output file to be the same
1495 as those of the input file.
1498 @itemx --enable-deterministic-archives
1499 @cindex deterministic archives
1500 @kindex --enable-deterministic-archives
1501 Operate in @emph{deterministic} mode. When copying archive members
1502 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1503 and use consistent file modes for all files.
1505 If @file{binutils} was configured with
1506 @option{--enable-deterministic-archives}, then this mode is on by default.
1507 It can be disabled with the @samp{-U} option, below.
1510 @itemx --disable-deterministic-archives
1511 @cindex deterministic archives
1512 @kindex --enable-deterministic-archives
1513 Do @emph{not} operate in @emph{deterministic} mode. This is the
1514 inverse of the @option{-D} option, above: when copying archive members
1515 and writing the archive index, use their actual UID, GID, timestamp,
1516 and file mode values.
1518 This is the default unless @file{binutils} was configured with
1519 @option{--enable-deterministic-archives}.
1522 Convert debugging information, if possible. This is not the default
1523 because only certain debugging formats are supported, and the
1524 conversion process can be time consuming.
1526 @item --gap-fill @var{val}
1527 Fill gaps between sections with @var{val}. This operation applies to
1528 the @emph{load address} (LMA) of the sections. It is done by increasing
1529 the size of the section with the lower address, and filling in the extra
1530 space created with @var{val}.
1532 @item --pad-to @var{address}
1533 Pad the output file up to the load address @var{address}. This is
1534 done by increasing the size of the last section. The extra space is
1535 filled in with the value specified by @option{--gap-fill} (default zero).
1537 @item --set-start @var{val}
1538 Set the start address of the new file to @var{val}. Not all object file
1539 formats support setting the start address.
1541 @item --change-start @var{incr}
1542 @itemx --adjust-start @var{incr}
1543 @cindex changing start address
1544 Change the start address by adding @var{incr}. Not all object file
1545 formats support setting the start address.
1547 @item --change-addresses @var{incr}
1548 @itemx --adjust-vma @var{incr}
1549 @cindex changing object addresses
1550 Change the VMA and LMA addresses of all sections, as well as the start
1551 address, by adding @var{incr}. Some object file formats do not permit
1552 section addresses to be changed arbitrarily. Note that this does not
1553 relocate the sections; if the program expects sections to be loaded at a
1554 certain address, and this option is used to change the sections such
1555 that they are loaded at a different address, the program may fail.
1557 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1558 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1559 @cindex changing section address
1560 Set or change both the VMA address and the LMA address of any section
1561 matching @var{sectionpattern}. If @samp{=} is used, the section
1562 address is set to @var{val}. Otherwise, @var{val} is added to or
1563 subtracted from the section address. See the comments under
1564 @option{--change-addresses}, above. If @var{sectionpattern} does not
1565 match any sections in the input file, a warning will be issued, unless
1566 @option{--no-change-warnings} is used.
1568 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1569 @cindex changing section LMA
1570 Set or change the LMA address of any sections matching
1571 @var{sectionpattern}. The LMA address is the address where the
1572 section will be loaded into memory at program load time. Normally
1573 this is the same as the VMA address, which is the address of the
1574 section at program run time, but on some systems, especially those
1575 where a program is held in ROM, the two can be different. If @samp{=}
1576 is used, the section address is set to @var{val}. Otherwise,
1577 @var{val} is added to or subtracted from the section address. See the
1578 comments under @option{--change-addresses}, above. If
1579 @var{sectionpattern} does not match any sections in the input file, a
1580 warning will be issued, unless @option{--no-change-warnings} is used.
1582 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1583 @cindex changing section VMA
1584 Set or change the VMA address of any section matching
1585 @var{sectionpattern}. The VMA address is the address where the
1586 section will be located once the program has started executing.
1587 Normally this is the same as the LMA address, which is the address
1588 where the section will be loaded into memory, but on some systems,
1589 especially those where a program is held in ROM, the two can be
1590 different. If @samp{=} is used, the section address is set to
1591 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1592 section address. See the comments under @option{--change-addresses},
1593 above. If @var{sectionpattern} does not match any sections in the
1594 input file, a warning will be issued, unless
1595 @option{--no-change-warnings} is used.
1597 @item --change-warnings
1598 @itemx --adjust-warnings
1599 If @option{--change-section-address} or @option{--change-section-lma} or
1600 @option{--change-section-vma} is used, and the section pattern does not
1601 match any sections, issue a warning. This is the default.
1603 @item --no-change-warnings
1604 @itemx --no-adjust-warnings
1605 Do not issue a warning if @option{--change-section-address} or
1606 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1607 if the section pattern does not match any sections.
1609 @item --set-section-flags @var{sectionpattern}=@var{flags}
1610 Set the flags for any sections matching @var{sectionpattern}. The
1611 @var{flags} argument is a comma separated string of flag names. The
1612 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1613 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1614 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1615 for a section which does not have contents, but it is not meaningful
1616 to clear the @samp{contents} flag of a section which does have
1617 contents--just remove the section instead. Not all flags are
1618 meaningful for all object file formats.
1620 @item --add-section @var{sectionname}=@var{filename}
1621 Add a new section named @var{sectionname} while copying the file. The
1622 contents of the new section are taken from the file @var{filename}. The
1623 size of the section will be the size of the file. This option only
1624 works on file formats which can support sections with arbitrary names.
1625 Note - it may be necessary to use the @option{--set-section-flags}
1626 option to set the attributes of the newly created section.
1628 @item --dump-section @var{sectionname}=@var{filename}
1629 Place the contents of section named @var{sectionname} into the file
1630 @var{filename}, overwriting any contents that may have been there
1631 previously. This option is the inverse of @option{--add-section}.
1632 This option is similar to the @option{--only-section} option except
1633 that it does not create a formatted file, it just dumps the contents
1634 as raw binary data, without applying any relocations. The option can
1635 be specified more than once.
1637 @item --update-section @var{sectionname}=@var{filename}
1638 Replace the existing contents of a section named @var{sectionname}
1639 with the contents of file @var{filename}. The size of the section
1640 will be adjusted to the size of the file. The section flags for
1641 @var{sectionname} will be unchanged. For ELF format files the section
1642 to segment mapping will also remain unchanged, something which is not
1643 possible using @option{--remove-section} followed by
1644 @option{--add-section}. The option can be specified more than once.
1646 Note - it is possible to use @option{--rename-section} and
1647 @option{--update-section} to both update and rename a section from one
1648 command line. In this case, pass the original section name to
1649 @option{--update-section}, and the original and new section names to
1650 @option{--rename-section}.
1652 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1653 Add a new symbol named @var{name} while copying the file. This option may be
1654 specified multiple times. If the @var{section} is given, the symbol will be
1655 associated with and relative to that section, otherwise it will be an ABS
1656 symbol. Specifying an undefined section will result in a fatal error. There
1657 is no check for the value, it will be taken as specified. Symbol flags can
1658 be specified and not all flags will be meaningful for all object file
1659 formats. By default, the symbol will be global. The special flag
1660 'before=@var{othersym}' will insert the new symbol in front of the specified
1661 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1662 symbol table in the order they appear.
1664 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1665 Rename a section from @var{oldname} to @var{newname}, optionally
1666 changing the section's flags to @var{flags} in the process. This has
1667 the advantage over using a linker script to perform the rename in that
1668 the output stays as an object file and does not become a linked
1671 This option is particularly helpful when the input format is binary,
1672 since this will always create a section called .data. If for example,
1673 you wanted instead to create a section called .rodata containing binary
1674 data you could use the following command line to achieve it:
1677 objcopy -I binary -O <output_format> -B <architecture> \
1678 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1679 <input_binary_file> <output_object_file>
1682 @item --long-section-names @{enable,disable,keep@}
1683 Controls the handling of long section names when processing @code{COFF}
1684 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1685 is to preserve long section names if any are present in the input file.
1686 The @samp{enable} and @samp{disable} options forcibly enable or disable
1687 the use of long section names in the output object; when @samp{disable}
1688 is in effect, any long section names in the input object will be truncated.
1689 The @samp{enable} option will only emit long section names if any are
1690 present in the inputs; this is mostly the same as @samp{keep}, but it
1691 is left undefined whether the @samp{enable} option might force the
1692 creation of an empty string table in the output file.
1694 @item --change-leading-char
1695 Some object file formats use special characters at the start of
1696 symbols. The most common such character is underscore, which compilers
1697 often add before every symbol. This option tells @command{objcopy} to
1698 change the leading character of every symbol when it converts between
1699 object file formats. If the object file formats use the same leading
1700 character, this option has no effect. Otherwise, it will add a
1701 character, or remove a character, or change a character, as
1704 @item --remove-leading-char
1705 If the first character of a global symbol is a special symbol leading
1706 character used by the object file format, remove the character. The
1707 most common symbol leading character is underscore. This option will
1708 remove a leading underscore from all global symbols. This can be useful
1709 if you want to link together objects of different file formats with
1710 different conventions for symbol names. This is different from
1711 @option{--change-leading-char} because it always changes the symbol name
1712 when appropriate, regardless of the object file format of the output
1715 @item --reverse-bytes=@var{num}
1716 Reverse the bytes in a section with output contents. A section length must
1717 be evenly divisible by the value given in order for the swap to be able to
1718 take place. Reversing takes place before the interleaving is performed.
1720 This option is used typically in generating ROM images for problematic
1721 target systems. For example, on some target boards, the 32-bit words
1722 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1723 regardless of the CPU byte order. Depending on the programming model, the
1724 endianness of the ROM may need to be modified.
1726 Consider a simple file with a section containing the following eight
1727 bytes: @code{12345678}.
1729 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1730 output file would be ordered @code{21436587}.
1732 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1733 output file would be ordered @code{43218765}.
1735 By using @samp{--reverse-bytes=2} for the above example, followed by
1736 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1737 output file would be ordered @code{34127856}.
1739 @item --srec-len=@var{ival}
1740 Meaningful only for srec output. Set the maximum length of the Srecords
1741 being produced to @var{ival}. This length covers both address, data and
1744 @item --srec-forceS3
1745 Meaningful only for srec output. Avoid generation of S1/S2 records,
1746 creating S3-only record format.
1748 @item --redefine-sym @var{old}=@var{new}
1749 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1750 when one is trying link two things together for which you have no
1751 source, and there are name collisions.
1753 @item --redefine-syms=@var{filename}
1754 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1755 listed in the file @var{filename}. @var{filename} is simply a flat file,
1756 with one symbol pair per line. Line comments may be introduced by the hash
1757 character. This option may be given more than once.
1760 Change all global symbols in the file to be weak. This can be useful
1761 when building an object which will be linked against other objects using
1762 the @option{-R} option to the linker. This option is only effective when
1763 using an object file format which supports weak symbols.
1765 @item --keep-symbols=@var{filename}
1766 Apply @option{--keep-symbol} option to each symbol listed in the file
1767 @var{filename}. @var{filename} is simply a flat file, with one symbol
1768 name per line. Line comments may be introduced by the hash character.
1769 This option may be given more than once.
1771 @item --strip-symbols=@var{filename}
1772 Apply @option{--strip-symbol} option to each symbol listed in the file
1773 @var{filename}. @var{filename} is simply a flat file, with one symbol
1774 name per line. Line comments may be introduced by the hash character.
1775 This option may be given more than once.
1777 @item --strip-unneeded-symbols=@var{filename}
1778 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1779 the file @var{filename}. @var{filename} is simply a flat file, with one
1780 symbol name per line. Line comments may be introduced by the hash
1781 character. This option may be given more than once.
1783 @item --keep-global-symbols=@var{filename}
1784 Apply @option{--keep-global-symbol} option to each symbol listed in the
1785 file @var{filename}. @var{filename} is simply a flat file, with one
1786 symbol name per line. Line comments may be introduced by the hash
1787 character. This option may be given more than once.
1789 @item --localize-symbols=@var{filename}
1790 Apply @option{--localize-symbol} option to each symbol listed in the file
1791 @var{filename}. @var{filename} is simply a flat file, with one symbol
1792 name per line. Line comments may be introduced by the hash character.
1793 This option may be given more than once.
1795 @item --globalize-symbols=@var{filename}
1796 Apply @option{--globalize-symbol} option to each symbol listed in the file
1797 @var{filename}. @var{filename} is simply a flat file, with one symbol
1798 name per line. Line comments may be introduced by the hash character.
1799 This option may be given more than once. Note: this option cannot be
1800 used in conjunction with the @option{-G} or @option{--keep-global-symbol}
1803 @item --weaken-symbols=@var{filename}
1804 Apply @option{--weaken-symbol} option to each symbol listed in the file
1805 @var{filename}. @var{filename} is simply a flat file, with one symbol
1806 name per line. Line comments may be introduced by the hash character.
1807 This option may be given more than once.
1809 @item --alt-machine-code=@var{index}
1810 If the output architecture has alternate machine codes, use the
1811 @var{index}th code instead of the default one. This is useful in case
1812 a machine is assigned an official code and the tool-chain adopts the
1813 new code, but other applications still depend on the original code
1814 being used. For ELF based architectures if the @var{index}
1815 alternative does not exist then the value is treated as an absolute
1816 number to be stored in the e_machine field of the ELF header.
1818 @item --writable-text
1819 Mark the output text as writable. This option isn't meaningful for all
1820 object file formats.
1822 @item --readonly-text
1823 Make the output text write protected. This option isn't meaningful for all
1824 object file formats.
1827 Mark the output file as demand paged. This option isn't meaningful for all
1828 object file formats.
1831 Mark the output file as impure. This option isn't meaningful for all
1832 object file formats.
1834 @item --prefix-symbols=@var{string}
1835 Prefix all symbols in the output file with @var{string}.
1837 @item --prefix-sections=@var{string}
1838 Prefix all section names in the output file with @var{string}.
1840 @item --prefix-alloc-sections=@var{string}
1841 Prefix all the names of all allocated sections in the output file with
1844 @item --add-gnu-debuglink=@var{path-to-file}
1845 Creates a .gnu_debuglink section which contains a reference to
1846 @var{path-to-file} and adds it to the output file. Note: the file at
1847 @var{path-to-file} must exist. Part of the process of adding the
1848 .gnu_debuglink section involves embedding a checksum of the contents
1849 of the debug info file into the section.
1851 If the debug info file is built in one location but it is going to be
1852 installed at a later time into a different location then do not use
1853 the path to the installed location. The @option{--add-gnu-debuglink}
1854 option will fail because the installed file does not exist yet.
1855 Instead put the debug info file in the current directory and use the
1856 @option{--add-gnu-debuglink} option without any directory components,
1860 objcopy --add-gnu-debuglink=foo.debug
1863 At debug time the debugger will attempt to look for the separate debug
1864 info file in a set of known locations. The exact set of these
1865 locations varies depending upon the distribution being used, but it
1870 @item * The same directory as the executable.
1872 @item * A sub-directory of the directory containing the executable
1875 @item * A global debug directory such as /usr/lib/debug.
1878 As long as the debug info file has been installed into one of these
1879 locations before the debugger is run everything should work
1882 @item --keep-file-symbols
1883 When stripping a file, perhaps with @option{--strip-debug} or
1884 @option{--strip-unneeded}, retain any symbols specifying source file names,
1885 which would otherwise get stripped.
1887 @item --only-keep-debug
1888 Strip a file, removing contents of any sections that would not be
1889 stripped by @option{--strip-debug} and leaving the debugging sections
1890 intact. In ELF files, this preserves all note sections in the output.
1892 Note - the section headers of the stripped sections are preserved,
1893 including their sizes, but the contents of the section are discarded.
1894 The section headers are preserved so that other tools can match up the
1895 debuginfo file with the real executable, even if that executable has
1896 been relocated to a different address space.
1898 The intention is that this option will be used in conjunction with
1899 @option{--add-gnu-debuglink} to create a two part executable. One a
1900 stripped binary which will occupy less space in RAM and in a
1901 distribution and the second a debugging information file which is only
1902 needed if debugging abilities are required. The suggested procedure
1903 to create these files is as follows:
1906 @item Link the executable as normal. Assuming that it is called
1908 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1909 create a file containing the debugging info.
1910 @item Run @code{objcopy --strip-debug foo} to create a
1911 stripped executable.
1912 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1913 to add a link to the debugging info into the stripped executable.
1916 Note---the choice of @code{.dbg} as an extension for the debug info
1917 file is arbitrary. Also the @code{--only-keep-debug} step is
1918 optional. You could instead do this:
1921 @item Link the executable as normal.
1922 @item Copy @code{foo} to @code{foo.full}
1923 @item Run @code{objcopy --strip-debug foo}
1924 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1927 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1928 full executable. It does not have to be a file created by the
1929 @option{--only-keep-debug} switch.
1931 Note---this switch is only intended for use on fully linked files. It
1932 does not make sense to use it on object files where the debugging
1933 information may be incomplete. Besides the gnu_debuglink feature
1934 currently only supports the presence of one filename containing
1935 debugging information, not multiple filenames on a one-per-object-file
1939 Remove the contents of all DWARF .dwo sections, leaving the
1940 remaining debugging sections and all symbols intact.
1941 This option is intended for use by the compiler as part of
1942 the @option{-gsplit-dwarf} option, which splits debug information
1943 between the .o file and a separate .dwo file. The compiler
1944 generates all debug information in the same file, then uses
1945 the @option{--extract-dwo} option to copy the .dwo sections to
1946 the .dwo file, then the @option{--strip-dwo} option to remove
1947 those sections from the original .o file.
1950 Extract the contents of all DWARF .dwo sections. See the
1951 @option{--strip-dwo} option for more information.
1953 @item --file-alignment @var{num}
1954 Specify the file alignment. Sections in the file will always begin at
1955 file offsets which are multiples of this number. This defaults to
1957 [This option is specific to PE targets.]
1959 @item --heap @var{reserve}
1960 @itemx --heap @var{reserve},@var{commit}
1961 Specify the number of bytes of memory to reserve (and optionally commit)
1962 to be used as heap for this program.
1963 [This option is specific to PE targets.]
1965 @item --image-base @var{value}
1966 Use @var{value} as the base address of your program or dll. This is
1967 the lowest memory location that will be used when your program or dll
1968 is loaded. To reduce the need to relocate and improve performance of
1969 your dlls, each should have a unique base address and not overlap any
1970 other dlls. The default is 0x400000 for executables, and 0x10000000
1972 [This option is specific to PE targets.]
1974 @item --section-alignment @var{num}
1975 Sets the section alignment. Sections in memory will always begin at
1976 addresses which are a multiple of this number. Defaults to 0x1000.
1977 [This option is specific to PE targets.]
1979 @item --stack @var{reserve}
1980 @itemx --stack @var{reserve},@var{commit}
1981 Specify the number of bytes of memory to reserve (and optionally commit)
1982 to be used as stack for this program.
1983 [This option is specific to PE targets.]
1985 @item --subsystem @var{which}
1986 @itemx --subsystem @var{which}:@var{major}
1987 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1988 Specifies the subsystem under which your program will execute. The
1989 legal values for @var{which} are @code{native}, @code{windows},
1990 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1991 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1992 the subsystem version also. Numeric values are also accepted for
1994 [This option is specific to PE targets.]
1996 @item --extract-symbol
1997 Keep the file's section flags and symbols but remove all section data.
1998 Specifically, the option:
2001 @item removes the contents of all sections;
2002 @item sets the size of every section to zero; and
2003 @item sets the file's start address to zero.
2006 This option is used to build a @file{.sym} file for a VxWorks kernel.
2007 It can also be a useful way of reducing the size of a @option{--just-symbols}
2010 @item --compress-debug-sections
2011 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
2012 ELF ABI. Note - if compression would actually make a section
2013 @emph{larger}, then it is not compressed.
2015 @item --compress-debug-sections=none
2016 @itemx --compress-debug-sections=zlib
2017 @itemx --compress-debug-sections=zlib-gnu
2018 @itemx --compress-debug-sections=zlib-gabi
2019 For ELF files, these options control how DWARF debug sections are
2020 compressed. @option{--compress-debug-sections=none} is equivalent
2021 to @option{--decompress-debug-sections}.
2022 @option{--compress-debug-sections=zlib} and
2023 @option{--compress-debug-sections=zlib-gabi} are equivalent to
2024 @option{--compress-debug-sections}.
2025 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
2026 sections using zlib. The debug sections are renamed to begin with
2027 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
2028 actually make a section @emph{larger}, then it is not compressed nor
2031 @item --decompress-debug-sections
2032 Decompress DWARF debug sections using zlib. The original section
2033 names of the compressed sections are restored.
2035 @item --elf-stt-common=yes
2036 @itemx --elf-stt-common=no
2037 For ELF files, these options control whether common symbols should be
2038 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2039 @option{--elf-stt-common=yes} converts common symbol type to
2040 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2041 type to @code{STT_OBJECT}.
2044 @itemx --no-merge-notes
2045 For ELF files, attempt (or do not attempt) to reduce the size of any
2046 SHT_NOTE type sections by removing duplicate notes.
2050 Show the version number of @command{objcopy}.
2052 @item --verilog-data-width=@var{bytes}
2053 For Verilog output, this options controls the number of bytes
2054 converted for each output data element. The input target controls the
2055 endianness of the conversion.
2059 Verbose output: list all object files modified. In the case of
2060 archives, @samp{objcopy -V} lists all members of the archive.
2063 Show a summary of the options to @command{objcopy}.
2066 Display a list showing all architectures and object formats available.
2072 @c man begin SEEALSO objcopy
2073 ld(1), objdump(1), and the Info entries for @file{binutils}.
2080 @cindex object file information
2083 @c man title objdump display information from object files.
2086 @c man begin SYNOPSIS objdump
2087 objdump [@option{-a}|@option{--archive-headers}]
2088 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2089 [@option{-C}|@option{--demangle}[=@var{style}] ]
2090 [@option{-d}|@option{--disassemble}[=@var{symbol}]]
2091 [@option{-D}|@option{--disassemble-all}]
2092 [@option{-z}|@option{--disassemble-zeroes}]
2093 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2094 [@option{-f}|@option{--file-headers}]
2095 [@option{-F}|@option{--file-offsets}]
2096 [@option{--file-start-context}]
2097 [@option{-g}|@option{--debugging}]
2098 [@option{-e}|@option{--debugging-tags}]
2099 [@option{-h}|@option{--section-headers}|@option{--headers}]
2100 [@option{-i}|@option{--info}]
2101 [@option{-j} @var{section}|@option{--section=}@var{section}]
2102 [@option{-l}|@option{--line-numbers}]
2103 [@option{-S}|@option{--source}]
2104 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2105 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2106 [@option{-p}|@option{--private-headers}]
2107 [@option{-P} @var{options}|@option{--private=}@var{options}]
2108 [@option{-r}|@option{--reloc}]
2109 [@option{-R}|@option{--dynamic-reloc}]
2110 [@option{-s}|@option{--full-contents}]
2111 [@option{-W[lLiaprmfFsoRtUuTgAckK]}|
2112 @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]]
2113 [@option{-G}|@option{--stabs}]
2114 [@option{-t}|@option{--syms}]
2115 [@option{-T}|@option{--dynamic-syms}]
2116 [@option{-x}|@option{--all-headers}]
2117 [@option{-w}|@option{--wide}]
2118 [@option{--start-address=}@var{address}]
2119 [@option{--stop-address=}@var{address}]
2120 [@option{--prefix-addresses}]
2121 [@option{--[no-]show-raw-insn}]
2122 [@option{--adjust-vma=}@var{offset}]
2123 [@option{--dwarf-depth=@var{n}}]
2124 [@option{--dwarf-start=@var{n}}]
2125 [@option{--no-recurse-limit}|@option{--recurse-limit}]
2126 [@option{--special-syms}]
2127 [@option{--prefix=}@var{prefix}]
2128 [@option{--prefix-strip=}@var{level}]
2129 [@option{--insn-width=}@var{width}]
2130 [@option{-V}|@option{--version}]
2131 [@option{-H}|@option{--help}]
2132 @var{objfile}@dots{}
2136 @c man begin DESCRIPTION objdump
2138 @command{objdump} displays information about one or more object files.
2139 The options control what particular information to display. This
2140 information is mostly useful to programmers who are working on the
2141 compilation tools, as opposed to programmers who just want their
2142 program to compile and work.
2144 @var{objfile}@dots{} are the object files to be examined. When you
2145 specify archives, @command{objdump} shows information on each of the member
2150 @c man begin OPTIONS objdump
2152 The long and short forms of options, shown here as alternatives, are
2153 equivalent. At least one option from the list
2154 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2158 @itemx --archive-header
2159 @cindex archive headers
2160 If any of the @var{objfile} files are archives, display the archive
2161 header information (in a format similar to @samp{ls -l}). Besides the
2162 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2163 the object file format of each archive member.
2165 @item --adjust-vma=@var{offset}
2166 @cindex section addresses in objdump
2167 @cindex VMA in objdump
2168 When dumping information, first add @var{offset} to all the section
2169 addresses. This is useful if the section addresses do not correspond to
2170 the symbol table, which can happen when putting sections at particular
2171 addresses when using a format which can not represent section addresses,
2174 @item -b @var{bfdname}
2175 @itemx --target=@var{bfdname}
2176 @cindex object code format
2177 Specify that the object-code format for the object files is
2178 @var{bfdname}. This option may not be necessary; @var{objdump} can
2179 automatically recognize many formats.
2183 objdump -b oasys -m vax -h fu.o
2186 displays summary information from the section headers (@option{-h}) of
2187 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2188 file in the format produced by Oasys compilers. You can list the
2189 formats available with the @option{-i} option.
2190 @xref{Target Selection}, for more information.
2193 @itemx --demangle[=@var{style}]
2194 @cindex demangling in objdump
2195 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2196 Besides removing any initial underscore prepended by the system, this
2197 makes C++ function names readable. Different compilers have different
2198 mangling styles. The optional demangling style argument can be used to
2199 choose an appropriate demangling style for your compiler. @xref{c++filt},
2200 for more information on demangling.
2202 @item --recurse-limit
2203 @itemx --no-recurse-limit
2204 @itemx --recursion-limit
2205 @itemx --no-recursion-limit
2206 Enables or disables a limit on the amount of recursion performed
2207 whilst demangling strings. Since the name mangling formats allow for
2208 an inifinite level of recursion it is possible to create strings whose
2209 decoding will exhaust the amount of stack space available on the host
2210 machine, triggering a memory fault. The limit tries to prevent this
2211 from happening by restricting recursion to 2048 levels of nesting.
2213 The default is for this limit to be enabled, but disabling it may be
2214 necessary in order to demangle truly complicated names. Note however
2215 that if the recursion limit is disabled then stack exhaustion is
2216 possible and any bug reports about such an event will be rejected.
2220 Display debugging information. This attempts to parse STABS
2221 debugging format information stored in the file and print it out using
2222 a C like syntax. If no STABS debuging was found this option
2223 falls back on the @option{-W} option to print any DWARF information in
2227 @itemx --debugging-tags
2228 Like @option{-g}, but the information is generated in a format compatible
2232 @itemx --disassemble
2233 @itemx --disassemble=@var{symbol}
2234 @cindex disassembling object code
2235 @cindex machine instructions
2236 Display the assembler mnemonics for the machine instructions from the
2237 input file. This option only disassembles those sections which are
2238 expected to contain instructions. If the optional @var{symbol}
2239 argument is given, then display the assembler mnemonics starting at
2240 @var{symbol}. If @var{symbol} is a function name then disassembly
2241 will stop at the end of the function, otherwise it will stop when the
2242 next symbol is encountered. If there are no matches for @var{symbol}
2243 then nothing will be displayed.
2245 Note if the @option{--dwarf=follow-links} option has also been enabled
2246 then any symbol tables in linked debug info files will be read in and
2247 used when disassembling.
2250 @itemx --disassemble-all
2251 Like @option{-d}, but disassemble the contents of all sections, not just
2252 those expected to contain instructions.
2254 This option also has a subtle effect on the disassembly of
2255 instructions in code sections. When option @option{-d} is in effect
2256 objdump will assume that any symbols present in a code section occur
2257 on the boundary between instructions and it will refuse to disassemble
2258 across such a boundary. When option @option{-D} is in effect however
2259 this assumption is supressed. This means that it is possible for the
2260 output of @option{-d} and @option{-D} to differ if, for example, data
2261 is stored in code sections.
2263 If the target is an ARM architecture this switch also has the effect
2264 of forcing the disassembler to decode pieces of data found in code
2265 sections as if they were instructions.
2267 Note if the @option{--dwarf=follow-links} option has also been enabled
2268 then any symbol tables in linked debug info files will be read in and
2269 used when disassembling.
2271 @item --prefix-addresses
2272 When disassembling, print the complete address on each line. This is
2273 the older disassembly format.
2277 @itemx --endian=@{big|little@}
2279 @cindex disassembly endianness
2280 Specify the endianness of the object files. This only affects
2281 disassembly. This can be useful when disassembling a file format which
2282 does not describe endianness information, such as S-records.
2285 @itemx --file-headers
2286 @cindex object file header
2287 Display summary information from the overall header of
2288 each of the @var{objfile} files.
2291 @itemx --file-offsets
2292 @cindex object file offsets
2293 When disassembling sections, whenever a symbol is displayed, also
2294 display the file offset of the region of data that is about to be
2295 dumped. If zeroes are being skipped, then when disassembly resumes,
2296 tell the user how many zeroes were skipped and the file offset of the
2297 location from where the disassembly resumes. When dumping sections,
2298 display the file offset of the location from where the dump starts.
2300 @item --file-start-context
2301 @cindex source code context
2302 Specify that when displaying interlisted source code/disassembly
2303 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2304 context to the start of the file.
2307 @itemx --section-headers
2309 @cindex section headers
2310 Display summary information from the section headers of the
2313 File segments may be relocated to nonstandard addresses, for example by
2314 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2315 @command{ld}. However, some object file formats, such as a.out, do not
2316 store the starting address of the file segments. In those situations,
2317 although @command{ld} relocates the sections correctly, using @samp{objdump
2318 -h} to list the file section headers cannot show the correct addresses.
2319 Instead, it shows the usual addresses, which are implicit for the
2322 Note, in some cases it is possible for a section to have both the
2323 READONLY and the NOREAD attributes set. In such cases the NOREAD
2324 attribute takes precedence, but @command{objdump} will report both
2325 since the exact setting of the flag bits might be important.
2329 Print a summary of the options to @command{objdump} and exit.
2333 @cindex architectures available
2334 @cindex object formats available
2335 Display a list showing all architectures and object formats available
2336 for specification with @option{-b} or @option{-m}.
2339 @itemx --section=@var{name}
2340 @cindex section information
2341 Display information only for section @var{name}.
2344 @itemx --line-numbers
2345 @cindex source filenames for object files
2346 Label the display (using debugging information) with the filename and
2347 source line numbers corresponding to the object code or relocs shown.
2348 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2350 @item -m @var{machine}
2351 @itemx --architecture=@var{machine}
2352 @cindex architecture
2353 @cindex disassembly architecture
2354 Specify the architecture to use when disassembling object files. This
2355 can be useful when disassembling object files which do not describe
2356 architecture information, such as S-records. You can list the available
2357 architectures with the @option{-i} option.
2359 If the target is an ARM architecture then this switch has an
2360 additional effect. It restricts the disassembly to only those
2361 instructions supported by the architecture specified by @var{machine}.
2362 If it is necessary to use this switch because the input file does not
2363 contain any architecture information, but it is also desired to
2364 disassemble all the instructions use @option{-marm}.
2366 @item -M @var{options}
2367 @itemx --disassembler-options=@var{options}
2368 Pass target specific information to the disassembler. Only supported on
2369 some targets. If it is necessary to specify more than one
2370 disassembler option then multiple @option{-M} options can be used or
2371 can be placed together into a comma separated list.
2373 For ARC, @option{dsp} controls the printing of DSP instructions,
2374 @option{spfp} selects the printing of FPX single precision FP
2375 instructions, @option{dpfp} selects the printing of FPX double
2376 precision FP instructions, @option{quarkse_em} selects the printing of
2377 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2378 of double precision assist instructions, @option{fpus} selects the
2379 printing of FPU single precision FP instructions, while @option{fpud}
2380 selects the printing of FPU double precision FP instructions.
2381 Additionally, one can choose to have all the immediates printed in
2382 hexadecimal using @option{hex}. By default, the short immediates are
2383 printed using the decimal representation, while the long immediate
2384 values are printed as hexadecimal.
2386 @option{cpu=...} allows to enforce a particular ISA when disassembling
2387 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2388 This might be useful to select ARC EM or HS ISA, because architecture is same
2389 for those and disassembler relies on private ELF header data to decide if code
2390 is for EM or HS. This option might be specified multiple times - only the
2391 latest value will be used. Valid values are same as for the assembler
2392 @option{-mcpu=...} option.
2394 If the target is an ARM architecture then this switch can be used to
2395 select which register name set is used during disassembler. Specifying
2396 @option{-M reg-names-std} (the default) will select the register names as
2397 used in ARM's instruction set documentation, but with register 13 called
2398 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2399 @option{-M reg-names-apcs} will select the name set used by the ARM
2400 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2401 just use @samp{r} followed by the register number.
2403 There are also two variants on the APCS register naming scheme enabled
2404 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2405 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2406 with the normal register names or the special register names).
2408 This option can also be used for ARM architectures to force the
2409 disassembler to interpret all instructions as Thumb instructions by
2410 using the switch @option{--disassembler-options=force-thumb}. This can be
2411 useful when attempting to disassemble thumb code produced by other
2414 For AArch64 targets this switch can be used to set whether instructions are
2415 disassembled as the most general instruction using the @option{-M no-aliases}
2416 option or whether instruction notes should be generated as comments in the
2417 disasssembly using @option{-M notes}.
2419 For the x86, some of the options duplicate functions of the @option{-m}
2420 switch, but allow finer grained control. Multiple selections from the
2421 following may be specified as a comma separated string.
2426 Select disassembly for the given architecture.
2430 Select between intel syntax mode and AT&T syntax mode.
2434 Select between AMD64 ISA and Intel64 ISA.
2436 @item intel-mnemonic
2438 Select between intel mnemonic mode and AT&T mnemonic mode.
2439 Note: @code{intel-mnemonic} implies @code{intel} and
2440 @code{att-mnemonic} implies @code{att}.
2447 Specify the default address size and operand size. These four options
2448 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2449 appear later in the option string.
2452 When in AT&T mode, instructs the disassembler to print a mnemonic
2453 suffix even when the suffix could be inferred by the operands.
2456 For PowerPC, the @option{-M} argument @option{raw} selects
2457 disasssembly of hardware insns rather than aliases. For example, you
2458 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2459 rather than @code{li}. All of the @option{-m} arguments for
2460 @command{gas} that select a CPU are supported. These are:
2461 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2462 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2463 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2464 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2465 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2466 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2467 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2468 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2469 @option{power8}, @option{power9}, @option{ppc}, @option{ppc32},
2470 @option{ppc64}, @option{ppc64bridge}, @option{ppcps}, @option{pwr},
2471 @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2472 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2473 @option{pwrx}, @option{titan}, and @option{vle}.
2474 @option{32} and @option{64} modify the default or a prior CPU
2475 selection, disabling and enabling 64-bit insns respectively. In
2476 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2477 and @option{spe} add capabilities to a previous @emph{or later} CPU
2478 selection. @option{any} will disassemble any opcode known to
2479 binutils, but in cases where an opcode has two different meanings or
2480 different arguments, you may not see the disassembly you expect.
2481 If you disassemble without giving a CPU selection, a default will be
2482 chosen from information gleaned by BFD from the object files headers,
2483 but the result again may not be as you expect.
2485 For MIPS, this option controls the printing of instruction mnemonic
2486 names and register names in disassembled instructions. Multiple
2487 selections from the following may be specified as a comma separated
2488 string, and invalid options are ignored:
2492 Print the 'raw' instruction mnemonic instead of some pseudo
2493 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2494 'sll' instead of 'nop', etc.
2497 Disassemble MSA instructions.
2500 Disassemble the virtualization ASE instructions.
2503 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2505 @item gpr-names=@var{ABI}
2506 Print GPR (general-purpose register) names as appropriate
2507 for the specified ABI. By default, GPR names are selected according to
2508 the ABI of the binary being disassembled.
2510 @item fpr-names=@var{ABI}
2511 Print FPR (floating-point register) names as
2512 appropriate for the specified ABI. By default, FPR numbers are printed
2515 @item cp0-names=@var{ARCH}
2516 Print CP0 (system control coprocessor; coprocessor 0) register names
2517 as appropriate for the CPU or architecture specified by
2518 @var{ARCH}. By default, CP0 register names are selected according to
2519 the architecture and CPU of the binary being disassembled.
2521 @item hwr-names=@var{ARCH}
2522 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2523 as appropriate for the CPU or architecture specified by
2524 @var{ARCH}. By default, HWR names are selected according to
2525 the architecture and CPU of the binary being disassembled.
2527 @item reg-names=@var{ABI}
2528 Print GPR and FPR names as appropriate for the selected ABI.
2530 @item reg-names=@var{ARCH}
2531 Print CPU-specific register names (CP0 register and HWR names)
2532 as appropriate for the selected CPU or architecture.
2535 For any of the options listed above, @var{ABI} or
2536 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2537 rather than names, for the selected types of registers.
2538 You can list the available values of @var{ABI} and @var{ARCH} using
2539 the @option{--help} option.
2541 For VAX, you can specify function entry addresses with @option{-M
2542 entry:0xf00ba}. You can use this multiple times to properly
2543 disassemble VAX binary files that don't contain symbol tables (like
2544 ROM dumps). In these cases, the function entry mask would otherwise
2545 be decoded as VAX instructions, which would probably lead the rest
2546 of the function being wrongly disassembled.
2549 @itemx --private-headers
2550 Print information that is specific to the object file format. The exact
2551 information printed depends upon the object file format. For some
2552 object file formats, no additional information is printed.
2554 @item -P @var{options}
2555 @itemx --private=@var{options}
2556 Print information that is specific to the object file format. The
2557 argument @var{options} is a comma separated list that depends on the
2558 format (the lists of options is displayed with the help).
2560 For XCOFF, the available options are:
2576 Not all object formats support this option. In particular the ELF
2577 format does not use it.
2581 @cindex relocation entries, in object file
2582 Print the relocation entries of the file. If used with @option{-d} or
2583 @option{-D}, the relocations are printed interspersed with the
2587 @itemx --dynamic-reloc
2588 @cindex dynamic relocation entries, in object file
2589 Print the dynamic relocation entries of the file. This is only
2590 meaningful for dynamic objects, such as certain types of shared
2591 libraries. As for @option{-r}, if used with @option{-d} or
2592 @option{-D}, the relocations are printed interspersed with the
2596 @itemx --full-contents
2597 @cindex sections, full contents
2598 @cindex object file sections
2599 Display the full contents of any sections requested. By default all
2600 non-empty sections are displayed.
2604 @cindex source disassembly
2605 @cindex disassembly, with source
2606 Display source code intermixed with disassembly, if possible. Implies
2609 @item --prefix=@var{prefix}
2610 @cindex Add prefix to absolute paths
2611 Specify @var{prefix} to add to the absolute paths when used with
2614 @item --prefix-strip=@var{level}
2615 @cindex Strip absolute paths
2616 Indicate how many initial directory names to strip off the hardwired
2617 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2619 @item --show-raw-insn
2620 When disassembling instructions, print the instruction in hex as well as
2621 in symbolic form. This is the default except when
2622 @option{--prefix-addresses} is used.
2624 @item --no-show-raw-insn
2625 When disassembling instructions, do not print the instruction bytes.
2626 This is the default when @option{--prefix-addresses} is used.
2628 @item --insn-width=@var{width}
2629 @cindex Instruction width
2630 Display @var{width} bytes on a single line when disassembling
2633 @item -W[lLiaprmfFsoRtUuTgAckK]
2634 @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]
2635 @include debug.options.texi
2638 Enable additional checks for consistency of Dwarf information.
2644 @cindex debug symbols
2645 @cindex ELF object file format
2646 Display the full contents of any sections requested. Display the
2647 contents of the .stab and .stab.index and .stab.excl sections from an
2648 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2649 @code{.stab} debugging symbol-table entries are carried in an ELF
2650 section. In most other file formats, debugging symbol-table entries are
2651 interleaved with linkage symbols, and are visible in the @option{--syms}
2654 @item --start-address=@var{address}
2655 @cindex start-address
2656 Start displaying data at the specified address. This affects the output
2657 of the @option{-d}, @option{-r} and @option{-s} options.
2659 @item --stop-address=@var{address}
2660 @cindex stop-address
2661 Stop displaying data at the specified address. This affects the output
2662 of the @option{-d}, @option{-r} and @option{-s} options.
2666 @cindex symbol table entries, printing
2667 Print the symbol table entries of the file.
2668 This is similar to the information provided by the @samp{nm} program,
2669 although the display format is different. The format of the output
2670 depends upon the format of the file being dumped, but there are two main
2671 types. One looks like this:
2674 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2675 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2678 where the number inside the square brackets is the number of the entry
2679 in the symbol table, the @var{sec} number is the section number, the
2680 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2681 symbol's type, the @var{scl} number is the symbol's storage class and
2682 the @var{nx} value is the number of auxilary entries associated with
2683 the symbol. The last two fields are the symbol's value and its name.
2685 The other common output format, usually seen with ELF based files,
2689 00000000 l d .bss 00000000 .bss
2690 00000000 g .text 00000000 fred
2693 Here the first number is the symbol's value (sometimes refered to as
2694 its address). The next field is actually a set of characters and
2695 spaces indicating the flag bits that are set on the symbol. These
2696 characters are described below. Next is the section with which the
2697 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2698 not connected with any section), or @emph{*UND*} if the section is
2699 referenced in the file being dumped, but not defined there.
2701 After the section name comes another field, a number, which for common
2702 symbols is the alignment and for other symbol is the size. Finally
2703 the symbol's name is displayed.
2705 The flag characters are divided into 7 groups as follows:
2711 The symbol is a local (l), global (g), unique global (u), neither
2712 global nor local (a space) or both global and local (!). A
2713 symbol can be neither local or global for a variety of reasons, e.g.,
2714 because it is used for debugging, but it is probably an indication of
2715 a bug if it is ever both local and global. Unique global symbols are
2716 a GNU extension to the standard set of ELF symbol bindings. For such
2717 a symbol the dynamic linker will make sure that in the entire process
2718 there is just one symbol with this name and type in use.
2721 The symbol is weak (w) or strong (a space).
2724 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2727 The symbol is a warning (W) or a normal symbol (a space). A warning
2728 symbol's name is a message to be displayed if the symbol following the
2729 warning symbol is ever referenced.
2733 The symbol is an indirect reference to another symbol (I), a function
2734 to be evaluated during reloc processing (i) or a normal symbol (a
2739 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2740 normal symbol (a space).
2745 The symbol is the name of a function (F) or a file (f) or an object
2746 (O) or just a normal symbol (a space).
2750 @itemx --dynamic-syms
2751 @cindex dynamic symbol table entries, printing
2752 Print the dynamic symbol table entries of the file. This is only
2753 meaningful for dynamic objects, such as certain types of shared
2754 libraries. This is similar to the information provided by the @samp{nm}
2755 program when given the @option{-D} (@option{--dynamic}) option.
2757 The output format is similar to that produced by the @option{--syms}
2758 option, except that an extra field is inserted before the symbol's
2759 name, giving the version information associated with the symbol.
2760 If the version is the default version to be used when resolving
2761 unversioned references to the symbol then it's displayed as is,
2762 otherwise it's put into parentheses.
2764 @item --special-syms
2765 When displaying symbols include those which the target considers to be
2766 special in some way and which would not normally be of interest to the
2771 Print the version number of @command{objdump} and exit.
2774 @itemx --all-headers
2775 @cindex all header information, object file
2776 @cindex header information, all
2777 Display all available header information, including the symbol table and
2778 relocation entries. Using @option{-x} is equivalent to specifying all of
2779 @option{-a -f -h -p -r -t}.
2783 @cindex wide output, printing
2784 Format some lines for output devices that have more than 80 columns.
2785 Also do not truncate symbol names when they are displayed.
2788 @itemx --disassemble-zeroes
2789 Normally the disassembly output will skip blocks of zeroes. This
2790 option directs the disassembler to disassemble those blocks, just like
2797 @c man begin SEEALSO objdump
2798 nm(1), readelf(1), and the Info entries for @file{binutils}.
2806 @cindex archive contents
2807 @cindex symbol index
2809 @c man title ranlib generate index to archive.
2812 @c man begin SYNOPSIS ranlib
2813 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2817 @c man begin DESCRIPTION ranlib
2819 @command{ranlib} generates an index to the contents of an archive and
2820 stores it in the archive. The index lists each symbol defined by a
2821 member of an archive that is a relocatable object file.
2823 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2825 An archive with such an index speeds up linking to the library and
2826 allows routines in the library to call each other without regard to
2827 their placement in the archive.
2829 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2830 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2835 @c man begin OPTIONS ranlib
2841 Show usage information for @command{ranlib}.
2846 Show the version number of @command{ranlib}.
2849 @cindex deterministic archives
2850 @kindex --enable-deterministic-archives
2851 Operate in @emph{deterministic} mode. The symbol map archive member's
2852 header will show zero for the UID, GID, and timestamp. When this
2853 option is used, multiple runs will produce identical output files.
2855 If @file{binutils} was configured with
2856 @option{--enable-deterministic-archives}, then this mode is on by
2857 default. It can be disabled with the @samp{-U} option, described
2861 Update the timestamp of the symbol map of an archive.
2864 @cindex deterministic archives
2865 @kindex --enable-deterministic-archives
2866 Do @emph{not} operate in @emph{deterministic} mode. This is the
2867 inverse of the @samp{-D} option, above: the archive index will get
2868 actual UID, GID, timestamp, and file mode values.
2870 If @file{binutils} was configured @emph{without}
2871 @option{--enable-deterministic-archives}, then this mode is on by
2879 @c man begin SEEALSO ranlib
2880 ar(1), nm(1), and the Info entries for @file{binutils}.
2888 @cindex section sizes
2890 @c man title size list section sizes and total size.
2893 @c man begin SYNOPSIS size
2894 size [@option{-A}|@option{-B}|@option{-G}|@option{--format=}@var{compatibility}]
2896 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2898 [@option{-t}|@option{--totals}]
2899 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2900 [@var{objfile}@dots{}]
2904 @c man begin DESCRIPTION size
2906 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2907 size---for each of the object or archive files @var{objfile} in its
2908 argument list. By default, one line of output is generated for each
2909 object file or each module in an archive.
2911 @var{objfile}@dots{} are the object files to be examined.
2912 If none are specified, the file @code{a.out} will be used.
2916 @c man begin OPTIONS size
2918 The command-line options have the following meanings:
2924 @itemx --format=@var{compatibility}
2925 @cindex @command{size} display format
2926 Using one of these options, you can choose whether the output from @sc{gnu}
2927 @command{size} resembles output from System V @command{size} (using @option{-A},
2928 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2929 @option{--format=berkeley}). The default is the one-line format similar to
2930 Berkeley's. Alternatively, you can choose the GNU format output
2931 (using @option{-G}, or @option{--format=gnu}), this is similar to
2932 Berkeley's output format, but sizes are counted differently.
2933 @c Bonus for doc-source readers: you can also say --format=strange (or
2934 @c anything else that starts with 's') for sysv, and --format=boring (or
2935 @c anything else that starts with 'b') for Berkeley.
2937 Here is an example of the Berkeley (default) format of output from
2940 $ size --format=Berkeley ranlib size
2941 text data bss dec hex filename
2942 294880 81920 11592 388392 5ed28 ranlib
2943 294880 81920 11888 388688 5ee50 size
2946 The Berkeley style output counts read only data in the @code{text}
2947 column, not in the @code{data} column, the @code{dec} and @code{hex}
2948 columns both display the sum of the @code{text}, @code{data}, and
2949 @code{bss} columns in decimal and hexadecimal respectively.
2951 The GNU format counts read only data in the @code{data} column, not
2952 the @code{text} column, and only displays the sum of the @code{text},
2953 @code{data}, and @code{bss} columns once, in the @code{total} column.
2954 The @option{--radix} option can be used to change the number base for
2955 all columns. Here is the same data displayed with GNU conventions:
2958 $ size --format=GNU ranlib size
2959 text data bss total filename
2960 279880 96920 11592 388392 ranlib
2961 279880 96920 11888 388688 size
2965 This is the same data, but displayed closer to System V conventions:
2968 $ size --format=SysV ranlib size
2986 Show a summary of acceptable arguments and options.
2991 @itemx --radix=@var{number}
2992 @cindex @command{size} number format
2993 @cindex radix for section sizes
2994 Using one of these options, you can control whether the size of each
2995 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2996 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2997 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2998 values (8, 10, 16) are supported. The total size is always given in two
2999 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
3000 octal and hexadecimal if you're using @option{-o}.
3003 Print total size of common symbols in each file. When using Berkeley
3004 or GNU format these are included in the bss size.
3008 Show totals of all objects listed (Berkeley or GNU format mode only).
3010 @item --target=@var{bfdname}
3011 @cindex object code format
3012 Specify that the object-code format for @var{objfile} is
3013 @var{bfdname}. This option may not be necessary; @command{size} can
3014 automatically recognize many formats.
3015 @xref{Target Selection}, for more information.
3019 Display the version number of @command{size}.
3025 @c man begin SEEALSO size
3026 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
3033 @cindex listings strings
3034 @cindex printing strings
3035 @cindex strings, printing
3037 @c man title strings print the strings of printable characters in files.
3040 @c man begin SYNOPSIS strings
3041 strings [@option{-afovV}] [@option{-}@var{min-len}]
3042 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
3043 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
3044 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
3045 [@option{-}] [@option{--all}] [@option{--print-file-name}]
3046 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
3047 [@option{-w}] [@option{--include-all-whitespace}]
3048 [@option{-s}] [@option{--output-separator}@var{sep_string}]
3049 [@option{--help}] [@option{--version}] @var{file}@dots{}
3053 @c man begin DESCRIPTION strings
3055 For each @var{file} given, @sc{gnu} @command{strings} prints the
3056 printable character sequences that are at least 4 characters long (or
3057 the number given with the options below) and are followed by an
3058 unprintable character.
3060 Depending upon how the strings program was configured it will default
3061 to either displaying all the printable sequences that it can find in
3062 each file, or only those sequences that are in loadable, initialized
3063 data sections. If the file type in unrecognizable, or if strings is
3064 reading from stdin then it will always display all of the printable
3065 sequences that it can find.
3067 For backwards compatibility any file that occurs after a command-line
3068 option of just @option{-} will also be scanned in full, regardless of
3069 the presence of any @option{-d} option.
3071 @command{strings} is mainly useful for determining the contents of
3076 @c man begin OPTIONS strings
3082 Scan the whole file, regardless of what sections it contains or
3083 whether those sections are loaded or initialized. Normally this is
3084 the default behaviour, but strings can be configured so that the
3085 @option{-d} is the default instead.
3087 The @option{-} option is position dependent and forces strings to
3088 perform full scans of any file that is mentioned after the @option{-}
3089 on the command line, even if the @option{-d} option has been
3094 Only print strings from initialized, loaded data sections in the
3095 file. This may reduce the amount of garbage in the output, but it
3096 also exposes the strings program to any security flaws that may be
3097 present in the BFD library used to scan and load sections. Strings
3098 can be configured so that this option is the default behaviour. In
3099 such cases the @option{-a} option can be used to avoid using the BFD
3100 library and instead just print all of the strings found in the file.
3103 @itemx --print-file-name
3104 Print the name of the file before each string.
3107 Print a summary of the program usage on the standard output and exit.
3109 @item -@var{min-len}
3110 @itemx -n @var{min-len}
3111 @itemx --bytes=@var{min-len}
3112 Print sequences of characters that are at least @var{min-len} characters
3113 long, instead of the default 4.
3116 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3117 act like @samp{-t d} instead. Since we can not be compatible with both
3118 ways, we simply chose one.
3120 @item -t @var{radix}
3121 @itemx --radix=@var{radix}
3122 Print the offset within the file before each string. The single
3123 character argument specifies the radix of the offset---@samp{o} for
3124 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3126 @item -e @var{encoding}
3127 @itemx --encoding=@var{encoding}
3128 Select the character encoding of the strings that are to be found.
3129 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3130 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3131 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3132 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3133 littleendian. Useful for finding wide character strings. (@samp{l}
3134 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3136 @item -T @var{bfdname}
3137 @itemx --target=@var{bfdname}
3138 @cindex object code format
3139 Specify an object code format other than your system's default format.
3140 @xref{Target Selection}, for more information.
3145 Print the program version number on the standard output and exit.
3148 @itemx --include-all-whitespace
3149 By default tab and space characters are included in the strings that
3150 are displayed, but other whitespace characters, such a newlines and
3151 carriage returns, are not. The @option{-w} option changes this so
3152 that all whitespace characters are considered to be part of a string.
3155 @itemx --output-separator
3156 By default, output strings are delimited by a new-line. This option
3157 allows you to supply any string to be used as the output record
3158 separator. Useful with --include-all-whitespace where strings
3159 may contain new-lines internally.
3165 @c man begin SEEALSO strings
3166 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3167 and the Info entries for @file{binutils}.
3175 @cindex removing symbols
3176 @cindex discarding symbols
3177 @cindex symbols, discarding
3179 @c man title strip Discard symbols from object files.
3182 @c man begin SYNOPSIS strip
3183 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3184 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3185 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3186 [@option{-s}|@option{--strip-all}]
3187 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3188 [@option{--strip-dwo}]
3189 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3190 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3191 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3192 [@option{-w}|@option{--wildcard}]
3193 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3194 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3195 [@option{--remove-relocations=}@var{sectionpattern}]
3196 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3197 [@option{-D}|@option{--enable-deterministic-archives}]
3198 [@option{-U}|@option{--disable-deterministic-archives}]
3199 [@option{--keep-file-symbols}]
3200 [@option{--only-keep-debug}]
3201 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3202 [@option{--help}] [@option{--info}]
3203 @var{objfile}@dots{}
3207 @c man begin DESCRIPTION strip
3209 @sc{gnu} @command{strip} discards all symbols from object files
3210 @var{objfile}. The list of object files may include archives.
3211 At least one object file must be given.
3213 @command{strip} modifies the files named in its argument,
3214 rather than writing modified copies under different names.
3218 @c man begin OPTIONS strip
3221 @item -F @var{bfdname}
3222 @itemx --target=@var{bfdname}
3223 Treat the original @var{objfile} as a file with the object
3224 code format @var{bfdname}, and rewrite it in the same format.
3225 @xref{Target Selection}, for more information.
3228 Show a summary of the options to @command{strip} and exit.
3231 Display a list showing all architectures and object formats available.
3233 @item -I @var{bfdname}
3234 @itemx --input-target=@var{bfdname}
3235 Treat the original @var{objfile} as a file with the object
3236 code format @var{bfdname}.
3237 @xref{Target Selection}, for more information.
3239 @item -O @var{bfdname}
3240 @itemx --output-target=@var{bfdname}
3241 Replace @var{objfile} with a file in the output format @var{bfdname}.
3242 @xref{Target Selection}, for more information.
3244 @item -R @var{sectionname}
3245 @itemx --remove-section=@var{sectionname}
3246 Remove any section named @var{sectionname} from the output file, in
3247 addition to whatever sections would otherwise be removed. This
3248 option may be given more than once. Note that using this option
3249 inappropriately may make the output file unusable. The wildcard
3250 character @samp{*} may be given at the end of @var{sectionname}. If
3251 so, then any section starting with @var{sectionname} will be removed.
3253 If the first character of @var{sectionpattern} is the exclamation
3254 point (!) then matching sections will not be removed even if an
3255 earlier use of @option{--remove-section} on the same command line
3256 would otherwise remove it. For example:
3259 --remove-section=.text.* --remove-section=!.text.foo
3262 will remove all sections matching the pattern '.text.*', but will not
3263 remove the section '.text.foo'.
3265 @item --remove-relocations=@var{sectionpattern}
3266 Remove relocations from the output file for any section matching
3267 @var{sectionpattern}. This option may be given more than once. Note
3268 that using this option inappropriately may make the output file
3269 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3273 --remove-relocations=.text.*
3276 will remove the relocations for all sections matching the patter
3279 If the first character of @var{sectionpattern} is the exclamation
3280 point (!) then matching sections will not have their relocation
3281 removed even if an earlier use of @option{--remove-relocations} on the
3282 same command line would otherwise cause the relocations to be removed.
3286 --remove-relocations=.text.* --remove-relocations=!.text.foo
3289 will remove all relocations for sections matching the pattern
3290 '.text.*', but will not remove relocations for the section
3300 @itemx --strip-debug
3301 Remove debugging symbols only.
3304 Remove the contents of all DWARF .dwo sections, leaving the
3305 remaining debugging sections and all symbols intact.
3306 See the description of this option in the @command{objcopy} section
3307 for more information.
3309 @item --strip-unneeded
3310 Remove all symbols that are not needed for relocation processing.
3312 @item -K @var{symbolname}
3313 @itemx --keep-symbol=@var{symbolname}
3314 When stripping symbols, keep symbol @var{symbolname} even if it would
3315 normally be stripped. This option may be given more than once.
3318 @itemx --merge-notes
3319 @itemx --no-merge-notes
3320 For ELF files, attempt (or do not attempt) to reduce the size of any
3321 SHT_NOTE type sections by removing duplicate notes. The default is to
3322 attempt this reduction unless stripping debug or DWO information.
3324 @item -N @var{symbolname}
3325 @itemx --strip-symbol=@var{symbolname}
3326 Remove symbol @var{symbolname} from the source file. This option may be
3327 given more than once, and may be combined with strip options other than
3331 Put the stripped output in @var{file}, rather than replacing the
3332 existing file. When this argument is used, only one @var{objfile}
3333 argument may be specified.
3336 @itemx --preserve-dates
3337 Preserve the access and modification dates of the file.
3340 @itemx --enable-deterministic-archives
3341 @cindex deterministic archives
3342 @kindex --enable-deterministic-archives
3343 Operate in @emph{deterministic} mode. When copying archive members
3344 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3345 and use consistent file modes for all files.
3347 If @file{binutils} was configured with
3348 @option{--enable-deterministic-archives}, then this mode is on by default.
3349 It can be disabled with the @samp{-U} option, below.
3352 @itemx --disable-deterministic-archives
3353 @cindex deterministic archives
3354 @kindex --enable-deterministic-archives
3355 Do @emph{not} operate in @emph{deterministic} mode. This is the
3356 inverse of the @option{-D} option, above: when copying archive members
3357 and writing the archive index, use their actual UID, GID, timestamp,
3358 and file mode values.
3360 This is the default unless @file{binutils} was configured with
3361 @option{--enable-deterministic-archives}.
3365 Permit regular expressions in @var{symbolname}s used in other command
3366 line options. The question mark (?), asterisk (*), backslash (\) and
3367 square brackets ([]) operators can be used anywhere in the symbol
3368 name. If the first character of the symbol name is the exclamation
3369 point (!) then the sense of the switch is reversed for that symbol.
3376 would cause strip to only keep symbols that start with the letters
3377 ``fo'', but to discard the symbol ``foo''.
3380 @itemx --discard-all
3381 Remove non-global symbols.
3384 @itemx --discard-locals
3385 Remove compiler-generated local symbols.
3386 (These usually start with @samp{L} or @samp{.}.)
3388 @item --keep-file-symbols
3389 When stripping a file, perhaps with @option{--strip-debug} or
3390 @option{--strip-unneeded}, retain any symbols specifying source file names,
3391 which would otherwise get stripped.
3393 @item --only-keep-debug
3394 Strip a file, emptying the contents of any sections that would not be
3395 stripped by @option{--strip-debug} and leaving the debugging sections
3396 intact. In ELF files, this preserves all the note sections in the
3399 Note - the section headers of the stripped sections are preserved,
3400 including their sizes, but the contents of the section are discarded.
3401 The section headers are preserved so that other tools can match up the
3402 debuginfo file with the real executable, even if that executable has
3403 been relocated to a different address space.
3405 The intention is that this option will be used in conjunction with
3406 @option{--add-gnu-debuglink} to create a two part executable. One a
3407 stripped binary which will occupy less space in RAM and in a
3408 distribution and the second a debugging information file which is only
3409 needed if debugging abilities are required. The suggested procedure
3410 to create these files is as follows:
3413 @item Link the executable as normal. Assuming that it is called
3415 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3416 create a file containing the debugging info.
3417 @item Run @code{objcopy --strip-debug foo} to create a
3418 stripped executable.
3419 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3420 to add a link to the debugging info into the stripped executable.
3423 Note---the choice of @code{.dbg} as an extension for the debug info
3424 file is arbitrary. Also the @code{--only-keep-debug} step is
3425 optional. You could instead do this:
3428 @item Link the executable as normal.
3429 @item Copy @code{foo} to @code{foo.full}
3430 @item Run @code{strip --strip-debug foo}
3431 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3434 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3435 full executable. It does not have to be a file created by the
3436 @option{--only-keep-debug} switch.
3438 Note---this switch is only intended for use on fully linked files. It
3439 does not make sense to use it on object files where the debugging
3440 information may be incomplete. Besides the gnu_debuglink feature
3441 currently only supports the presence of one filename containing
3442 debugging information, not multiple filenames on a one-per-object-file
3447 Show the version number for @command{strip}.
3451 Verbose output: list all object files modified. In the case of
3452 archives, @samp{strip -v} lists all members of the archive.
3458 @c man begin SEEALSO strip
3459 the Info entries for @file{binutils}.
3463 @node c++filt, addr2line, strip, Top
3467 @cindex demangling C++ symbols
3469 @c man title cxxfilt Demangle C++ and Java symbols.
3472 @c man begin SYNOPSIS cxxfilt
3473 c++filt [@option{-_}|@option{--strip-underscore}]
3474 [@option{-n}|@option{--no-strip-underscore}]
3475 [@option{-p}|@option{--no-params}]
3476 [@option{-t}|@option{--types}]
3477 [@option{-i}|@option{--no-verbose}]
3478 [@option{-r}|@option{--no-recurse-limit}]
3479 [@option{-R}|@option{--recurse-limit}]
3480 [@option{-s} @var{format}|@option{--format=}@var{format}]
3481 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3485 @c man begin DESCRIPTION cxxfilt
3488 The C++ and Java languages provide function overloading, which means
3489 that you can write many functions with the same name, providing that
3490 each function takes parameters of different types. In order to be
3491 able to distinguish these similarly named functions C++ and Java
3492 encode them into a low-level assembler name which uniquely identifies
3493 each different version. This process is known as @dfn{mangling}. The
3495 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3496 MS-DOS this program is named @command{CXXFILT}.}
3497 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3498 names into user-level names so that they can be read.
3500 Every alphanumeric word (consisting of letters, digits, underscores,
3501 dollars, or periods) seen in the input is a potential mangled name.
3502 If the name decodes into a C++ name, the C++ name replaces the
3503 low-level name in the output, otherwise the original word is output.
3504 In this way you can pass an entire assembler source file, containing
3505 mangled names, through @command{c++filt} and see the same source file
3506 containing demangled names.
3508 You can also use @command{c++filt} to decipher individual symbols by
3509 passing them on the command line:
3512 c++filt @var{symbol}
3515 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3516 names from the standard input instead. All the results are printed on
3517 the standard output. The difference between reading names from the
3518 command line versus reading names from the standard input is that
3519 command-line arguments are expected to be just mangled names and no
3520 checking is performed to separate them from surrounding text. Thus
3527 will work and demangle the name to ``f()'' whereas:
3533 will not work. (Note the extra comma at the end of the mangled
3534 name which makes it invalid). This command however will work:
3537 echo _Z1fv, | c++filt -n
3540 and will display ``f(),'', i.e., the demangled name followed by a
3541 trailing comma. This behaviour is because when the names are read
3542 from the standard input it is expected that they might be part of an
3543 assembler source file where there might be extra, extraneous
3544 characters trailing after a mangled name. For example:
3547 .type _Z1fv, @@function
3552 @c man begin OPTIONS cxxfilt
3556 @itemx --strip-underscore
3557 On some systems, both the C and C++ compilers put an underscore in front
3558 of every name. For example, the C name @code{foo} gets the low-level
3559 name @code{_foo}. This option removes the initial underscore. Whether
3560 @command{c++filt} removes the underscore by default is target dependent.
3563 @itemx --no-strip-underscore
3564 Do not remove the initial underscore.
3568 When demangling the name of a function, do not display the types of
3569 the function's parameters.
3573 Attempt to demangle types as well as function names. This is disabled
3574 by default since mangled types are normally only used internally in
3575 the compiler, and they can be confused with non-mangled names. For example,
3576 a function called ``a'' treated as a mangled type name would be
3577 demangled to ``signed char''.
3581 Do not include implementation details (if any) in the demangled
3586 @itemx --recurse-limit
3587 @itemx --no-recurse-limit
3588 @itemx --recursion-limit
3589 @itemx --no-recursion-limit
3590 Enables or disables a limit on the amount of recursion performed
3591 whilst demangling strings. Since the name mangling formats allow for
3592 an inifinite level of recursion it is possible to create strings whose
3593 decoding will exhaust the amount of stack space available on the host
3594 machine, triggering a memory fault. The limit tries to prevent this
3595 from happening by restricting recursion to 2048 levels of nesting.
3597 The default is for this limit to be enabled, but disabling it may be
3598 necessary in order to demangle truly complicated names. Note however
3599 that if the recursion limit is disabled then stack exhaustion is
3600 possible and any bug reports about such an event will be rejected.
3602 The @option{-r} option is a synonym for the
3603 @option{--no-recurse-limit} option. The @option{-R} option is a
3604 synonym for the @option{--recurse-limit} option.
3606 @item -s @var{format}
3607 @itemx --format=@var{format}
3608 @command{c++filt} can decode various methods of mangling, used by
3609 different compilers. The argument to this option selects which
3614 Automatic selection based on executable (the default method)
3616 the one used by the @sc{gnu} C++ compiler (g++)
3618 the one used by the Lucid compiler (lcc)
3620 the one specified by the C++ Annotated Reference Manual
3622 the one used by the HP compiler (aCC)
3624 the one used by the EDG compiler
3626 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3628 the one used by the @sc{gnu} Java compiler (gcj)
3630 the one used by the @sc{gnu} Ada compiler (GNAT).
3634 Print a summary of the options to @command{c++filt} and exit.
3637 Print the version number of @command{c++filt} and exit.
3643 @c man begin SEEALSO cxxfilt
3644 the Info entries for @file{binutils}.
3649 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3650 user interface are subject to change in future releases. In particular,
3651 a command-line option may be required in the future to decode a name
3652 passed as an argument on the command line; in other words,
3655 c++filt @var{symbol}
3659 may in a future release become
3662 c++filt @var{option} @var{symbol}
3670 @cindex address to file name and line number
3672 @c man title addr2line convert addresses into file names and line numbers.
3675 @c man begin SYNOPSIS addr2line
3676 addr2line [@option{-a}|@option{--addresses}]
3677 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3678 [@option{-C}|@option{--demangle}[=@var{style}]]
3679 [@option{-r}|@option{--no-recurse-limit}]
3680 [@option{-R}|@option{--recurse-limit}]
3681 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3682 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3683 [@option{-i}|@option{--inlines}]
3684 [@option{-p}|@option{--pretty-print}]
3685 [@option{-j}|@option{--section=}@var{name}]
3686 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3691 @c man begin DESCRIPTION addr2line
3693 @command{addr2line} translates addresses into file names and line numbers.
3694 Given an address in an executable or an offset in a section of a relocatable
3695 object, it uses the debugging information to figure out which file name and
3696 line number are associated with it.
3698 The executable or relocatable object to use is specified with the @option{-e}
3699 option. The default is the file @file{a.out}. The section in the relocatable
3700 object to use is specified with the @option{-j} option.
3702 @command{addr2line} has two modes of operation.
3704 In the first, hexadecimal addresses are specified on the command line,
3705 and @command{addr2line} displays the file name and line number for each
3708 In the second, @command{addr2line} reads hexadecimal addresses from
3709 standard input, and prints the file name and line number for each
3710 address on standard output. In this mode, @command{addr2line} may be used
3711 in a pipe to convert dynamically chosen addresses.
3713 The format of the output is @samp{FILENAME:LINENO}. By default
3714 each input address generates one line of output.
3716 Two options can generate additional lines before each
3717 @samp{FILENAME:LINENO} line (in that order).
3719 If the @option{-a} option is used then a line with the input address
3722 If the @option{-f} option is used, then a line with the
3723 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3724 containing the address.
3726 One option can generate additional lines after the
3727 @samp{FILENAME:LINENO} line.
3729 If the @option{-i} option is used and the code at the given address is
3730 present there because of inlining by the compiler then additional
3731 lines are displayed afterwards. One or two extra lines (if the
3732 @option{-f} option is used) are displayed for each inlined function.
3734 Alternatively if the @option{-p} option is used then each input
3735 address generates a single, long, output line containing the address,
3736 the function name, the file name and the line number. If the
3737 @option{-i} option has also been used then any inlined functions will
3738 be displayed in the same manner, but on separate lines, and prefixed
3739 by the text @samp{(inlined by)}.
3741 If the file name or function name can not be determined,
3742 @command{addr2line} will print two question marks in their place. If the
3743 line number can not be determined, @command{addr2line} will print 0.
3747 @c man begin OPTIONS addr2line
3749 The long and short forms of options, shown here as alternatives, are
3755 Display the address before the function name, file and line number
3756 information. The address is printed with a @samp{0x} prefix to easily
3759 @item -b @var{bfdname}
3760 @itemx --target=@var{bfdname}
3761 @cindex object code format
3762 Specify that the object-code format for the object files is
3766 @itemx --demangle[=@var{style}]
3767 @cindex demangling in objdump
3768 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3769 Besides removing any initial underscore prepended by the system, this
3770 makes C++ function names readable. Different compilers have different
3771 mangling styles. The optional demangling style argument can be used to
3772 choose an appropriate demangling style for your compiler. @xref{c++filt},
3773 for more information on demangling.
3775 @item -e @var{filename}
3776 @itemx --exe=@var{filename}
3777 Specify the name of the executable for which addresses should be
3778 translated. The default file is @file{a.out}.
3782 Display function names as well as file and line number information.
3786 Display only the base of each file name.
3790 If the address belongs to a function that was inlined, the source
3791 information for all enclosing scopes back to the first non-inlined
3792 function will also be printed. For example, if @code{main} inlines
3793 @code{callee1} which inlines @code{callee2}, and address is from
3794 @code{callee2}, the source information for @code{callee1} and @code{main}
3795 will also be printed.
3799 Read offsets relative to the specified section instead of absolute addresses.
3802 @itemx --pretty-print
3803 Make the output more human friendly: each location are printed on one line.
3804 If option @option{-i} is specified, lines for all enclosing scopes are
3805 prefixed with @samp{(inlined by)}.
3809 @itemx --recurse-limit
3810 @itemx --no-recurse-limit
3811 @itemx --recursion-limit
3812 @itemx --no-recursion-limit
3813 Enables or disables a limit on the amount of recursion performed
3814 whilst demangling strings. Since the name mangling formats allow for
3815 an inifinite level of recursion it is possible to create strings whose
3816 decoding will exhaust the amount of stack space available on the host
3817 machine, triggering a memory fault. The limit tries to prevent this
3818 from happening by restricting recursion to 2048 levels of nesting.
3820 The default is for this limit to be enabled, but disabling it may be
3821 necessary in order to demangle truly complicated names. Note however
3822 that if the recursion limit is disabled then stack exhaustion is
3823 possible and any bug reports about such an event will be rejected.
3825 The @option{-r} option is a synonym for the
3826 @option{--no-recurse-limit} option. The @option{-R} option is a
3827 synonym for the @option{--recurse-limit} option.
3829 Note this option is only effective if the @option{-C} or
3830 @option{--demangle} option has been enabled.
3837 @c man begin SEEALSO addr2line
3838 Info entries for @file{binutils}.
3845 @command{windmc} may be used to generator Windows message resources.
3848 @emph{Warning:} @command{windmc} is not always built as part of the binary
3849 utilities, since it is only useful for Windows targets.
3852 @c man title windmc generates Windows message resources.
3855 @c man begin SYNOPSIS windmc
3856 windmc [options] input-file
3860 @c man begin DESCRIPTION windmc
3862 @command{windmc} reads message definitions from an input file (.mc) and
3863 translate them into a set of output files. The output files may be of
3868 A C header file containing the message definitions.
3871 A resource file compilable by the @command{windres} tool.
3874 One or more binary files containing the resource data for a specific
3878 A C include file that maps message id's to their symbolic name.
3881 The exact description of these different formats is available in
3882 documentation from Microsoft.
3884 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3885 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3886 Windows Message Compiler.
3890 @c man begin OPTIONS windmc
3895 Specifies that the input file specified is ASCII. This is the default
3900 Specifies that messages in the output @code{bin} files should be in ASCII
3905 Specifies that @code{bin} filenames should have to be prefixed by the
3906 basename of the source file.
3910 Sets the customer bit in all message id's.
3912 @item -C @var{codepage}
3913 @itemx --codepage_in @var{codepage}
3914 Sets the default codepage to be used to convert input file to UTF16. The
3915 default is ocdepage 1252.
3918 @itemx --decimal_values
3919 Outputs the constants in the header file in decimal. Default is using
3923 @itemx --extension @var{ext}
3924 The extension for the header file. The default is .h extension.
3926 @item -F @var{target}
3927 @itemx --target @var{target}
3928 Specify the BFD format to use for a bin file as output. This
3929 is a BFD target name; you can use the @option{--help} option to see a list
3930 of supported targets. Normally @command{windmc} will use the default
3931 format, which is the first one listed by the @option{--help} option.
3933 @ref{Target Selection}.
3937 @itemx --headerdir @var{path}
3938 The target directory of the generated header file. The default is the
3943 Displays a list of command-line options and then exits.
3945 @item -m @var{characters}
3946 @itemx --maxlength @var{characters}
3947 Instructs @command{windmc} to generate a warning if the length
3948 of any message exceeds the number specified.
3951 @itemx --nullterminate
3952 Terminate message text in @code{bin} files by zero. By default they are
3953 terminated by CR/LF.
3956 @itemx --hresult_use
3957 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3958 file, using HRESULT definitions. Status codes are used if the flag is not
3961 @item -O @var{codepage}
3962 @itemx --codepage_out @var{codepage}
3963 Sets the default codepage to be used to output text files. The default
3967 @itemx --rcdir @var{path}
3968 The target directory for the generated @code{rc} script and the generated
3969 @code{bin} files that the resource compiler script includes. The default
3970 is the current directory.
3974 Specifies that the input file is UTF16.
3977 @itemx --unicode_out
3978 Specifies that messages in the output @code{bin} file should be in UTF16
3979 format. This is the default behaviour.
3983 Enable verbose mode.
3987 Prints the version number for @command{windmc}.
3990 @itemx --xdgb @var{path}
3991 The path of the @code{dbg} C include file that maps message id's to the
3992 symbolic name. No such file is generated without specifying the switch.
3998 @c man begin SEEALSO windmc
3999 the Info entries for @file{binutils}.
4006 @command{windres} may be used to manipulate Windows resources.
4009 @emph{Warning:} @command{windres} is not always built as part of the binary
4010 utilities, since it is only useful for Windows targets.
4013 @c man title windres manipulate Windows resources.
4016 @c man begin SYNOPSIS windres
4017 windres [options] [input-file] [output-file]
4021 @c man begin DESCRIPTION windres
4023 @command{windres} reads resources from an input file and copies them into
4024 an output file. Either file may be in one of three formats:
4028 A text format read by the Resource Compiler.
4031 A binary format generated by the Resource Compiler.
4034 A COFF object or executable.
4037 The exact description of these different formats is available in
4038 documentation from Microsoft.
4040 When @command{windres} converts from the @code{rc} format to the @code{res}
4041 format, it is acting like the Windows Resource Compiler. When
4042 @command{windres} converts from the @code{res} format to the @code{coff}
4043 format, it is acting like the Windows @code{CVTRES} program.
4045 When @command{windres} generates an @code{rc} file, the output is similar
4046 but not identical to the format expected for the input. When an input
4047 @code{rc} file refers to an external filename, an output @code{rc} file
4048 will instead include the file contents.
4050 If the input or output format is not specified, @command{windres} will
4051 guess based on the file name, or, for the input file, the file contents.
4052 A file with an extension of @file{.rc} will be treated as an @code{rc}
4053 file, a file with an extension of @file{.res} will be treated as a
4054 @code{res} file, and a file with an extension of @file{.o} or
4055 @file{.exe} will be treated as a @code{coff} file.
4057 If no output file is specified, @command{windres} will print the resources
4058 in @code{rc} format to standard output.
4060 The normal use is for you to write an @code{rc} file, use @command{windres}
4061 to convert it to a COFF object file, and then link the COFF file into
4062 your application. This will make the resources described in the
4063 @code{rc} file available to Windows.
4067 @c man begin OPTIONS windres
4070 @item -i @var{filename}
4071 @itemx --input @var{filename}
4072 The name of the input file. If this option is not used, then
4073 @command{windres} will use the first non-option argument as the input file
4074 name. If there are no non-option arguments, then @command{windres} will
4075 read from standard input. @command{windres} can not read a COFF file from
4078 @item -o @var{filename}
4079 @itemx --output @var{filename}
4080 The name of the output file. If this option is not used, then
4081 @command{windres} will use the first non-option argument, after any used
4082 for the input file name, as the output file name. If there is no
4083 non-option argument, then @command{windres} will write to standard output.
4084 @command{windres} can not write a COFF file to standard output. Note,
4085 for compatibility with @command{rc} the option @option{-fo} is also
4086 accepted, but its use is not recommended.
4088 @item -J @var{format}
4089 @itemx --input-format @var{format}
4090 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4091 @samp{coff}. If no input format is specified, @command{windres} will
4092 guess, as described above.
4094 @item -O @var{format}
4095 @itemx --output-format @var{format}
4096 The output format to generate. @var{format} may be @samp{res},
4097 @samp{rc}, or @samp{coff}. If no output format is specified,
4098 @command{windres} will guess, as described above.
4100 @item -F @var{target}
4101 @itemx --target @var{target}
4102 Specify the BFD format to use for a COFF file as input or output. This
4103 is a BFD target name; you can use the @option{--help} option to see a list
4104 of supported targets. Normally @command{windres} will use the default
4105 format, which is the first one listed by the @option{--help} option.
4107 @ref{Target Selection}.
4110 @item --preprocessor @var{program}
4111 When @command{windres} reads an @code{rc} file, it runs it through the C
4112 preprocessor first. This option may be used to specify the preprocessor
4113 to use, including any leading arguments. The default preprocessor
4114 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
4116 @item --preprocessor-arg @var{option}
4117 When @command{windres} reads an @code{rc} file, it runs it through
4118 the C preprocessor first. This option may be used to specify additional
4119 text to be passed to preprocessor on its command line.
4120 This option can be used multiple times to add multiple options to the
4121 preprocessor command line.
4123 @item -I @var{directory}
4124 @itemx --include-dir @var{directory}
4125 Specify an include directory to use when reading an @code{rc} file.
4126 @command{windres} will pass this to the preprocessor as an @option{-I}
4127 option. @command{windres} will also search this directory when looking for
4128 files named in the @code{rc} file. If the argument passed to this command
4129 matches any of the supported @var{formats} (as described in the @option{-J}
4130 option), it will issue a deprecation warning, and behave just like the
4131 @option{-J} option. New programs should not use this behaviour. If a
4132 directory happens to match a @var{format}, simple prefix it with @samp{./}
4133 to disable the backward compatibility.
4135 @item -D @var{target}
4136 @itemx --define @var{sym}[=@var{val}]
4137 Specify a @option{-D} option to pass to the preprocessor when reading an
4140 @item -U @var{target}
4141 @itemx --undefine @var{sym}
4142 Specify a @option{-U} option to pass to the preprocessor when reading an
4146 Ignored for compatibility with rc.
4149 Enable verbose mode. This tells you what the preprocessor is if you
4153 @item --codepage @var{val}
4154 Specify the default codepage to use when reading an @code{rc} file.
4155 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4156 codepage code. The valid range is from zero up to 0xffff, but the
4157 validity of the codepage is host and configuration dependent.
4160 @item --language @var{val}
4161 Specify the default language to use when reading an @code{rc} file.
4162 @var{val} should be a hexadecimal language code. The low eight bits are
4163 the language, and the high eight bits are the sublanguage.
4165 @item --use-temp-file
4166 Use a temporary file to instead of using popen to read the output of
4167 the preprocessor. Use this option if the popen implementation is buggy
4168 on the host (eg., certain non-English language versions of Windows 95 and
4169 Windows 98 are known to have buggy popen where the output will instead
4172 @item --no-use-temp-file
4173 Use popen, not a temporary file, to read the output of the preprocessor.
4174 This is the default behaviour.
4178 Prints a usage summary.
4182 Prints the version number for @command{windres}.
4185 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4186 this will turn on parser debugging.
4192 @c man begin SEEALSO windres
4193 the Info entries for @file{binutils}.
4202 @command{dlltool} is used to create the files needed to create dynamic
4203 link libraries (DLLs) on systems which understand PE format image
4204 files such as Windows. A DLL contains an export table which contains
4205 information that the runtime loader needs to resolve references from a
4206 referencing program.
4208 The export table is generated by this program by reading in a
4209 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4210 will be in the DLL. A @file{.o} file can contain information in
4211 special @samp{.drectve} sections with export information.
4214 @emph{Note:} @command{dlltool} is not always built as part of the
4215 binary utilities, since it is only useful for those targets which
4219 @c man title dlltool Create files needed to build and use DLLs.
4222 @c man begin SYNOPSIS dlltool
4223 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4224 [@option{-b}|@option{--base-file} @var{base-file-name}]
4225 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4226 [@option{-z}|@option{--output-def} @var{def-file-name}]
4227 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4228 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4229 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4230 [@option{--exclude-symbols} @var{list}]
4231 [@option{--no-default-excludes}]
4232 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4233 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4234 [@option{-a}|@option{--add-indirect}]
4235 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4236 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4237 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4238 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4239 [@option{--use-nul-prefixed-import-tables}]
4240 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4241 [@option{-i}|@option{--interwork}]
4242 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4243 [@option{-v}|@option{--verbose}]
4244 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4245 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4246 [object-file @dots{}]
4250 @c man begin DESCRIPTION dlltool
4252 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4253 @option{-b} options as well as object files specified on the command
4254 line. It then processes these inputs and if the @option{-e} option has
4255 been specified it creates a exports file. If the @option{-l} option
4256 has been specified it creates a library file and if the @option{-z} option
4257 has been specified it creates a def file. Any or all of the @option{-e},
4258 @option{-l} and @option{-z} options can be present in one invocation of
4261 When creating a DLL, along with the source for the DLL, it is necessary
4262 to have three other files. @command{dlltool} can help with the creation of
4265 The first file is a @file{.def} file which specifies which functions are
4266 exported from the DLL, which functions the DLL imports, and so on. This
4267 is a text file and can be created by hand, or @command{dlltool} can be used
4268 to create it using the @option{-z} option. In this case @command{dlltool}
4269 will scan the object files specified on its command line looking for
4270 those functions which have been specially marked as being exported and
4271 put entries for them in the @file{.def} file it creates.
4273 In order to mark a function as being exported from a DLL, it needs to
4274 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4275 section of the object file. This can be done in C by using the
4279 asm (".section .drectve");
4280 asm (".ascii \"-export:my_func\"");
4282 int my_func (void) @{ @dots{} @}
4285 The second file needed for DLL creation is an exports file. This file
4286 is linked with the object files that make up the body of the DLL and it
4287 handles the interface between the DLL and the outside world. This is a
4288 binary file and it can be created by giving the @option{-e} option to
4289 @command{dlltool} when it is creating or reading in a @file{.def} file.
4291 The third file needed for DLL creation is the library file that programs
4292 will link with in order to access the functions in the DLL (an `import
4293 library'). This file can be created by giving the @option{-l} option to
4294 dlltool when it is creating or reading in a @file{.def} file.
4296 If the @option{-y} option is specified, dlltool generates a delay-import
4297 library that can be used instead of the normal import library to allow
4298 a program to link to the dll only as soon as an imported function is
4299 called for the first time. The resulting executable will need to be
4300 linked to the static delayimp library containing __delayLoadHelper2(),
4301 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4303 @command{dlltool} builds the library file by hand, but it builds the
4304 exports file by creating temporary files containing assembler statements
4305 and then assembling these. The @option{-S} command-line option can be
4306 used to specify the path to the assembler that dlltool will use,
4307 and the @option{-f} option can be used to pass specific flags to that
4308 assembler. The @option{-n} can be used to prevent dlltool from deleting
4309 these temporary assembler files when it is done, and if @option{-n} is
4310 specified twice then this will prevent dlltool from deleting the
4311 temporary object files it used to build the library.
4313 Here is an example of creating a DLL from a source file @samp{dll.c} and
4314 also creating a program (from an object file called @samp{program.o})
4319 dlltool -e exports.o -l dll.lib dll.o
4320 gcc dll.o exports.o -o dll.dll
4321 gcc program.o dll.lib -o program
4325 @command{dlltool} may also be used to query an existing import library
4326 to determine the name of the DLL to which it is associated. See the
4327 description of the @option{-I} or @option{--identify} option.
4331 @c man begin OPTIONS dlltool
4333 The command-line options have the following meanings:
4337 @item -d @var{filename}
4338 @itemx --input-def @var{filename}
4339 @cindex input .def file
4340 Specifies the name of a @file{.def} file to be read in and processed.
4342 @item -b @var{filename}
4343 @itemx --base-file @var{filename}
4345 Specifies the name of a base file to be read in and processed. The
4346 contents of this file will be added to the relocation section in the
4347 exports file generated by dlltool.
4349 @item -e @var{filename}
4350 @itemx --output-exp @var{filename}
4351 Specifies the name of the export file to be created by dlltool.
4353 @item -z @var{filename}
4354 @itemx --output-def @var{filename}
4355 Specifies the name of the @file{.def} file to be created by dlltool.
4357 @item -l @var{filename}
4358 @itemx --output-lib @var{filename}
4359 Specifies the name of the library file to be created by dlltool.
4361 @item -y @var{filename}
4362 @itemx --output-delaylib @var{filename}
4363 Specifies the name of the delay-import library file to be created by dlltool.
4365 @item --export-all-symbols
4366 Treat all global and weak defined symbols found in the input object
4367 files as symbols to be exported. There is a small list of symbols which
4368 are not exported by default; see the @option{--no-default-excludes}
4369 option. You may add to the list of symbols to not export by using the
4370 @option{--exclude-symbols} option.
4372 @item --no-export-all-symbols
4373 Only export symbols explicitly listed in an input @file{.def} file or in
4374 @samp{.drectve} sections in the input object files. This is the default
4375 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4376 attributes in the source code.
4378 @item --exclude-symbols @var{list}
4379 Do not export the symbols in @var{list}. This is a list of symbol names
4380 separated by comma or colon characters. The symbol names should not
4381 contain a leading underscore. This is only meaningful when
4382 @option{--export-all-symbols} is used.
4384 @item --no-default-excludes
4385 When @option{--export-all-symbols} is used, it will by default avoid
4386 exporting certain special symbols. The current list of symbols to avoid
4387 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4388 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4389 to go ahead and export these special symbols. This is only meaningful
4390 when @option{--export-all-symbols} is used.
4393 @itemx --as @var{path}
4394 Specifies the path, including the filename, of the assembler to be used
4395 to create the exports file.
4397 @item -f @var{options}
4398 @itemx --as-flags @var{options}
4399 Specifies any specific command-line options to be passed to the
4400 assembler when building the exports file. This option will work even if
4401 the @option{-S} option is not used. This option only takes one argument,
4402 and if it occurs more than once on the command line, then later
4403 occurrences will override earlier occurrences. So if it is necessary to
4404 pass multiple options to the assembler they should be enclosed in
4408 @itemx --dll-name @var{name}
4409 Specifies the name to be stored in the @file{.def} file as the name of
4410 the DLL when the @option{-e} option is used. If this option is not
4411 present, then the filename given to the @option{-e} option will be
4412 used as the name of the DLL.
4414 @item -m @var{machine}
4415 @itemx -machine @var{machine}
4416 Specifies the type of machine for which the library file should be
4417 built. @command{dlltool} has a built in default type, depending upon how
4418 it was created, but this option can be used to override that. This is
4419 normally only useful when creating DLLs for an ARM processor, when the
4420 contents of the DLL are actually encode using Thumb instructions.
4423 @itemx --add-indirect
4424 Specifies that when @command{dlltool} is creating the exports file it
4425 should add a section which allows the exported functions to be
4426 referenced without using the import library. Whatever the hell that
4430 @itemx --add-underscore
4431 Specifies that when @command{dlltool} is creating the exports file it
4432 should prepend an underscore to the names of @emph{all} exported symbols.
4434 @item --no-leading-underscore
4435 @item --leading-underscore
4436 Specifies whether standard symbol should be forced to be prefixed, or
4439 @item --add-stdcall-underscore
4440 Specifies that when @command{dlltool} is creating the exports file it
4441 should prepend an underscore to the names of exported @emph{stdcall}
4442 functions. Variable names and non-stdcall function names are not modified.
4443 This option is useful when creating GNU-compatible import libs for third
4444 party DLLs that were built with MS-Windows tools.
4448 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4449 of stdcall functions that will be imported from the DLL. This is
4450 useful when creating an import library for a DLL which exports stdcall
4451 functions but without the usual @samp{@@<number>} symbol name suffix.
4453 This does not change the naming of symbols provided by the import library
4454 to programs linked against it, but only the entries in the import table
4455 (ie the .idata section).
4458 @itemx --add-stdcall-alias
4459 Specifies that when @command{dlltool} is creating the exports file it
4460 should add aliases for stdcall symbols without @samp{@@ <number>}
4461 in addition to the symbols with @samp{@@ <number>}.
4464 @itemx --ext-prefix-alias @var{prefix}
4465 Causes @command{dlltool} to create external aliases for all DLL
4466 imports with the specified prefix. The aliases are created for both
4467 external and import symbols with no leading underscore.
4471 Specifies that when @command{dlltool} is creating the exports and library
4472 files it should omit the @code{.idata4} section. This is for compatibility
4473 with certain operating systems.
4475 @item --use-nul-prefixed-import-tables
4476 Specifies that when @command{dlltool} is creating the exports and library
4477 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4478 element. This emulates old gnu import library generation of
4479 @code{dlltool}. By default this option is turned off.
4483 Specifies that when @command{dlltool} is creating the exports and library
4484 files it should omit the @code{.idata5} section. This is for compatibility
4485 with certain operating systems.
4487 @item -I @var{filename}
4488 @itemx --identify @var{filename}
4489 Specifies that @command{dlltool} should inspect the import library
4490 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4491 of the associated DLL(s). This can be performed in addition to any
4492 other operations indicated by the other options and arguments.
4493 @command{dlltool} fails if the import library does not exist or is not
4494 actually an import library. See also @option{--identify-strict}.
4496 @item --identify-strict
4497 Modifies the behavior of the @option{--identify} option, such
4498 that an error is reported if @var{filename} is associated with
4503 Specifies that @command{dlltool} should mark the objects in the library
4504 file and exports file that it produces as supporting interworking
4505 between ARM and Thumb code.
4509 Makes @command{dlltool} preserve the temporary assembler files it used to
4510 create the exports file. If this option is repeated then dlltool will
4511 also preserve the temporary object files it uses to create the library
4514 @item -t @var{prefix}
4515 @itemx --temp-prefix @var{prefix}
4516 Makes @command{dlltool} use @var{prefix} when constructing the names of
4517 temporary assembler and object files. By default, the temp file prefix
4518 is generated from the pid.
4522 Make dlltool describe what it is doing.
4526 Displays a list of command-line options and then exits.
4530 Displays dlltool's version number and then exits.
4537 * def file format:: The format of the dlltool @file{.def} file
4540 @node def file format
4541 @section The format of the @command{dlltool} @file{.def} file
4543 A @file{.def} file contains any number of the following commands:
4547 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4548 The result is going to be named @var{name}@code{.exe}.
4550 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4551 The result is going to be named @var{name}@code{.dll}.
4552 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4553 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4556 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4557 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4558 Declares @var{name1} as an exported symbol from the DLL, with optional
4559 ordinal number @var{integer}, or declares @var{name1} as an alias
4560 (forward) of the function @var{external-name} in the DLL.
4561 If @var{its_name} is specified, this name is used as string in export table.
4563 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4564 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4565 If you want to use LIBRARY as name then you need to quote it.
4567 @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{]} *}
4568 Declares that @var{external-name} or the exported function whose
4569 ordinal number is @var{integer} is to be imported from the file
4570 @var{module-name}. If @var{internal-name} is specified then this is
4571 the name that the imported function will be referred to in the body of
4573 If @var{its_name} is specified, this name is used as string in import table.
4574 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4575 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4576 If you want to use LIBRARY as name then you need to quote it.
4578 @item @code{DESCRIPTION} @var{string}
4579 Puts @var{string} into the output @file{.exp} file in the
4580 @code{.rdata} section.
4582 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4583 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4584 Generates @code{--stack} or @code{--heap}
4585 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4586 section. The linker will see this and act upon it.
4588 @item @code{CODE} @var{attr} @code{+}
4589 @item @code{DATA} @var{attr} @code{+}
4590 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4591 Generates @code{--attr} @var{section-name} @var{attr} in the output
4592 @code{.drectve} section, where @var{attr} is one of @code{READ},
4593 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4594 this and act upon it.
4599 @c man begin SEEALSO dlltool
4600 The Info pages for @file{binutils}.
4607 @cindex ELF file information
4610 @c man title readelf Displays information about ELF files.
4613 @c man begin SYNOPSIS readelf
4614 readelf [@option{-a}|@option{--all}]
4615 [@option{-h}|@option{--file-header}]
4616 [@option{-l}|@option{--program-headers}|@option{--segments}]
4617 [@option{-S}|@option{--section-headers}|@option{--sections}]
4618 [@option{-g}|@option{--section-groups}]
4619 [@option{-t}|@option{--section-details}]
4620 [@option{-e}|@option{--headers}]
4621 [@option{-s}|@option{--syms}|@option{--symbols}]
4622 [@option{--dyn-syms}]
4623 [@option{-n}|@option{--notes}]
4624 [@option{-r}|@option{--relocs}]
4625 [@option{-u}|@option{--unwind}]
4626 [@option{-d}|@option{--dynamic}]
4627 [@option{-V}|@option{--version-info}]
4628 [@option{-A}|@option{--arch-specific}]
4629 [@option{-D}|@option{--use-dynamic}]
4630 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4631 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4632 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4633 [@option{-z}|@option{--decompress}]
4634 [@option{-c}|@option{--archive-index}]
4635 [@option{-w[lLiaprmfFsoRtUuTgAckK]}|
4636 @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]]
4637 [@option{--dwarf-depth=@var{n}}]
4638 [@option{--dwarf-start=@var{n}}]
4639 [@option{-I}|@option{--histogram}]
4640 [@option{-v}|@option{--version}]
4641 [@option{-W}|@option{--wide}]
4642 [@option{-H}|@option{--help}]
4643 @var{elffile}@dots{}
4647 @c man begin DESCRIPTION readelf
4649 @command{readelf} displays information about one or more ELF format object
4650 files. The options control what particular information to display.
4652 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4653 64-bit ELF files are supported, as are archives containing ELF files.
4655 This program performs a similar function to @command{objdump} but it
4656 goes into more detail and it exists independently of the @sc{bfd}
4657 library, so if there is a bug in @sc{bfd} then readelf will not be
4662 @c man begin OPTIONS readelf
4664 The long and short forms of options, shown here as alternatives, are
4665 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4671 Equivalent to specifying @option{--file-header},
4672 @option{--program-headers}, @option{--sections}, @option{--symbols},
4673 @option{--relocs}, @option{--dynamic}, @option{--notes},
4674 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4675 @option{--section-groups} and @option{--histogram}.
4677 Note - this option does not enable @option{--use-dynamic} itself, so
4678 if that option is not present on the command line then dynamic symbols
4679 and dynamic relocs will not be displayed.
4682 @itemx --file-header
4683 @cindex ELF file header information
4684 Displays the information contained in the ELF header at the start of the
4688 @itemx --program-headers
4690 @cindex ELF program header information
4691 @cindex ELF segment information
4692 Displays the information contained in the file's segment headers, if it
4697 @itemx --section-headers
4698 @cindex ELF section information
4699 Displays the information contained in the file's section headers, if it
4703 @itemx --section-groups
4704 @cindex ELF section group information
4705 Displays the information contained in the file's section groups, if it
4709 @itemx --section-details
4710 @cindex ELF section information
4711 Displays the detailed section information. Implies @option{-S}.
4716 @cindex ELF symbol table information
4717 Displays the entries in symbol table section of the file, if it has one.
4718 If a symbol has version information associated with it then this is
4719 displayed as well. The version string is displayed as a suffix to the
4720 symbol name, preceeded by an @@ character. For example
4721 @samp{foo@@VER_1}. If the version is the default version to be used
4722 when resolving unversioned references to the symbol then it is
4723 displayed as a suffix preceeded by two @@ characters. For example
4724 @samp{foo@@@@VER_2}.
4727 @cindex ELF dynamic symbol table information
4728 Displays the entries in dynamic symbol table section of the file, if it
4729 has one. The output format is the same as the format used by the
4730 @option{--syms} option.
4734 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4739 Displays the contents of the NOTE segments and/or sections, if any.
4743 @cindex ELF reloc information
4744 Displays the contents of the file's relocation section, if it has one.
4748 @cindex unwind information
4749 Displays the contents of the file's unwind section, if it has one. Only
4750 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4751 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported. If
4752 support is not yet implemented for your architecture you could try
4753 dumping the contents of the @var{.eh_frames} section using the
4754 @option{--debug-dump=frames} or @option{--debug-dump=frames-interp}
4759 @cindex ELF dynamic section information
4760 Displays the contents of the file's dynamic section, if it has one.
4763 @itemx --version-info
4764 @cindex ELF version sections information
4765 Displays the contents of the version sections in the file, it they
4769 @itemx --arch-specific
4770 Displays architecture-specific information in the file, if there
4774 @itemx --use-dynamic
4775 When displaying symbols, this option makes @command{readelf} use the
4776 symbol hash tables in the file's dynamic section, rather than the
4777 symbol table sections.
4779 When displaying relocations, this option makes @command{readelf}
4780 display the dynamic relocations rather than the static relocations.
4782 @item -x <number or name>
4783 @itemx --hex-dump=<number or name>
4784 Displays the contents of the indicated section as a hexadecimal bytes.
4785 A number identifies a particular section by index in the section table;
4786 any other string identifies all sections with that name in the object file.
4788 @item -R <number or name>
4789 @itemx --relocated-dump=<number or name>
4790 Displays the contents of the indicated section as a hexadecimal
4791 bytes. A number identifies a particular section by index in the
4792 section table; any other string identifies all sections with that name
4793 in the object file. The contents of the section will be relocated
4794 before they are displayed.
4796 @item -p <number or name>
4797 @itemx --string-dump=<number or name>
4798 Displays the contents of the indicated section as printable strings.
4799 A number identifies a particular section by index in the section table;
4800 any other string identifies all sections with that name in the object file.
4804 Requests that the section(s) being dumped by @option{x}, @option{R} or
4805 @option{p} options are decompressed before being displayed. If the
4806 section(s) are not compressed then they are displayed as is.
4809 @itemx --archive-index
4810 @cindex Archive file symbol index information
4811 Displays the file symbol index information contained in the header part
4812 of binary archives. Performs the same function as the @option{t}
4813 command to @command{ar}, but without using the BFD library. @xref{ar}.
4815 @item -w[lLiaprmfFsoRtUuTgAckK]
4816 @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]
4817 @include debug.options.texi
4821 Display a histogram of bucket list lengths when displaying the contents
4822 of the symbol tables.
4826 Display the version number of readelf.
4830 Don't break output lines to fit into 80 columns. By default
4831 @command{readelf} breaks section header and segment listing lines for
4832 64-bit ELF files, so that they fit into 80 columns. This option causes
4833 @command{readelf} to print each section header resp. each segment one a
4834 single line, which is far more readable on terminals wider than 80 columns.
4838 Display the command-line options understood by @command{readelf}.
4845 @c man begin SEEALSO readelf
4846 objdump(1), and the Info entries for @file{binutils}.
4853 @cindex Update ELF header
4856 @c man title elfedit Update ELF header and program property of ELF files.
4859 @c man begin SYNOPSIS elfedit
4860 elfedit [@option{--input-mach=}@var{machine}]
4861 [@option{--input-type=}@var{type}]
4862 [@option{--input-osabi=}@var{osabi}]
4863 @option{--output-mach=}@var{machine}
4864 @option{--output-type=}@var{type}
4865 @option{--output-osabi=}@var{osabi}
4866 @option{--enable-x86-feature=}@var{feature}
4867 @option{--disable-x86-feature=}@var{feature}
4868 [@option{-v}|@option{--version}]
4869 [@option{-h}|@option{--help}]
4870 @var{elffile}@dots{}
4874 @c man begin DESCRIPTION elfedit
4876 @command{elfedit} updates the ELF header and program property of ELF
4877 files which have the matching ELF machine and file types. The options
4878 control how and which fields in the ELF header and program property
4881 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4882 64-bit ELF files are supported, as are archives containing ELF files.
4885 @c man begin OPTIONS elfedit
4887 The long and short forms of options, shown here as alternatives, are
4888 equivalent. At least one of the @option{--output-mach},
4889 @option{--output-type}, @option{--output-osabi},
4890 @option{--enable-x86-feature} and @option{--disable-x86-feature}
4891 options must be given.
4895 @item --input-mach=@var{machine}
4896 Set the matching input ELF machine type to @var{machine}. If
4897 @option{--input-mach} isn't specified, it will match any ELF
4900 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4901 @var{K1OM} and @var{x86-64}.
4903 @item --output-mach=@var{machine}
4904 Change the ELF machine type in the ELF header to @var{machine}. The
4905 supported ELF machine types are the same as @option{--input-mach}.
4907 @item --input-type=@var{type}
4908 Set the matching input ELF file type to @var{type}. If
4909 @option{--input-type} isn't specified, it will match any ELF file types.
4911 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4913 @item --output-type=@var{type}
4914 Change the ELF file type in the ELF header to @var{type}. The
4915 supported ELF types are the same as @option{--input-type}.
4917 @item --input-osabi=@var{osabi}
4918 Set the matching input ELF file OSABI to @var{osabi}. If
4919 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4921 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4922 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4923 @var{Solaris}, @var{AIX}, @var{Irix},
4924 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4925 @var{NSK}, @var{AROS} and @var{FenixOS}.
4927 @item --output-osabi=@var{osabi}
4928 Change the ELF OSABI in the ELF header to @var{osabi}. The
4929 supported ELF OSABI are the same as @option{--input-osabi}.
4931 @item --enable-x86-feature=@var{feature}
4932 Set the @var{feature} bit in program property in @var{exec} or @var{dyn}
4933 ELF files with machine types of @var{i386} or @var{x86-64}. The
4934 supported features are, @var{ibt} and @var{shstk}.
4936 @item --disable-x86-feature=@var{feature}
4937 Clear the @var{feature} bit in program property in @var{exec} or
4938 @var{dyn} ELF files with machine types of @var{i386} or @var{x86-64}.
4939 The supported features are the same as @option{--enable-x86-feature}.
4941 Note: @option{--enable-x86-feature} and @option{--disable-x86-feature}
4942 are available only on hosts with @samp{mmap} support.
4946 Display the version number of @command{elfedit}.
4950 Display the command-line options understood by @command{elfedit}.
4957 @c man begin SEEALSO elfedit
4958 readelf(1), and the Info entries for @file{binutils}.
4962 @node Common Options
4963 @chapter Common Options
4965 The following command-line options are supported by all of the
4966 programs described in this manual.
4968 @c man begin OPTIONS
4970 @include at-file.texi
4974 Display the command-line options supported by the program.
4977 Display the version number of the program.
4979 @c man begin OPTIONS
4983 @node Selecting the Target System
4984 @chapter Selecting the Target System
4986 You can specify two aspects of the target system to the @sc{gnu}
4987 binary file utilities, each in several ways:
4997 In the following summaries, the lists of ways to specify values are in
4998 order of decreasing precedence. The ways listed first override those
5001 The commands to list valid values only list the values for which the
5002 programs you are running were configured. If they were configured with
5003 @option{--enable-targets=all}, the commands list most of the available
5004 values, but a few are left out; not all targets can be configured in at
5005 once because some of them can only be configured @dfn{native} (on hosts
5006 with the same type as the target system).
5009 * Target Selection::
5010 * Architecture Selection::
5013 @node Target Selection
5014 @section Target Selection
5016 A @dfn{target} is an object file format. A given target may be
5017 supported for multiple architectures (@pxref{Architecture Selection}).
5018 A target selection may also have variations for different operating
5019 systems or architectures.
5021 The command to list valid target values is @samp{objdump -i}
5022 (the first column of output contains the relevant information).
5024 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
5025 @samp{a.out-sunos-big}.
5027 You can also specify a target using a configuration triplet. This is
5028 the same sort of name that is passed to @file{configure} to specify a
5029 target. When you use a configuration triplet as an argument, it must be
5030 fully canonicalized. You can see the canonical version of a triplet by
5031 running the shell script @file{config.sub} which is included with the
5034 Some sample configuration triplets are: @samp{m68k-hp-bsd},
5035 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
5037 @subheading @command{objdump} Target
5043 command-line option: @option{-b} or @option{--target}
5046 environment variable @code{GNUTARGET}
5049 deduced from the input file
5052 @subheading @command{objcopy} and @command{strip} Input Target
5058 command-line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5061 environment variable @code{GNUTARGET}
5064 deduced from the input file
5067 @subheading @command{objcopy} and @command{strip} Output Target
5073 command-line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5076 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5079 environment variable @code{GNUTARGET}
5082 deduced from the input file
5085 @subheading @command{nm}, @command{size}, and @command{strings} Target
5091 command-line option: @option{--target}
5094 environment variable @code{GNUTARGET}
5097 deduced from the input file
5100 @node Architecture Selection
5101 @section Architecture Selection
5103 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5104 to run. Its name may contain a colon, separating the name of the
5105 processor family from the name of the particular @sc{cpu}.
5107 The command to list valid architecture values is @samp{objdump -i} (the
5108 second column contains the relevant information).
5110 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5112 @subheading @command{objdump} Architecture
5118 command-line option: @option{-m} or @option{--architecture}
5121 deduced from the input file
5124 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5130 deduced from the input file
5133 @node Reporting Bugs
5134 @chapter Reporting Bugs
5136 @cindex reporting bugs
5138 Your bug reports play an essential role in making the binary utilities
5141 Reporting a bug may help you by bringing a solution to your problem, or
5142 it may not. But in any case the principal function of a bug report is
5143 to help the entire community by making the next version of the binary
5144 utilities work better. Bug reports are your contribution to their
5147 In order for a bug report to serve its purpose, you must include the
5148 information that enables us to fix the bug.
5151 * Bug Criteria:: Have you found a bug?
5152 * Bug Reporting:: How to report bugs
5156 @section Have You Found a Bug?
5157 @cindex bug criteria
5159 If you are not sure whether you have found a bug, here are some guidelines:
5162 @cindex fatal signal
5165 If a binary utility gets a fatal signal, for any input whatever, that is
5166 a bug. Reliable utilities never crash.
5168 @cindex error on valid input
5170 If a binary utility produces an error message for valid input, that is a
5174 If you are an experienced user of binary utilities, your suggestions for
5175 improvement are welcome in any case.
5179 @section How to Report Bugs
5181 @cindex bugs, reporting
5183 A number of companies and individuals offer support for @sc{gnu}
5184 products. If you obtained the binary utilities from a support
5185 organization, we recommend you contact that organization first.
5187 You can find contact information for many support companies and
5188 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5192 In any event, we also recommend that you send bug reports for the binary
5193 utilities to @value{BUGURL}.
5196 The fundamental principle of reporting bugs usefully is this:
5197 @strong{report all the facts}. If you are not sure whether to state a
5198 fact or leave it out, state it!
5200 Often people omit facts because they think they know what causes the
5201 problem and assume that some details do not matter. Thus, you might
5202 assume that the name of a file you use in an example does not matter.
5203 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5204 a stray memory reference which happens to fetch from the location where
5205 that pathname is stored in memory; perhaps, if the pathname were
5206 different, the contents of that location would fool the utility into
5207 doing the right thing despite the bug. Play it safe and give a
5208 specific, complete example. That is the easiest thing for you to do,
5209 and the most helpful.
5211 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5212 it is new to us. Therefore, always write your bug reports on the assumption
5213 that the bug has not been reported previously.
5215 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5216 bell?'' This cannot help us fix a bug, so it is basically useless. We
5217 respond by asking for enough details to enable us to investigate.
5218 You might as well expedite matters by sending them to begin with.
5220 To enable us to fix the bug, you should include all these things:
5224 The version of the utility. Each utility announces it if you start it
5225 with the @option{--version} argument.
5227 Without this, we will not know whether there is any point in looking for
5228 the bug in the current version of the binary utilities.
5231 Any patches you may have applied to the source, including any patches
5232 made to the @code{BFD} library.
5235 The type of machine you are using, and the operating system name and
5239 What compiler (and its version) was used to compile the utilities---e.g.
5243 The command arguments you gave the utility to observe the bug. To
5244 guarantee you will not omit something important, list them all. A copy
5245 of the Makefile (or the output from make) is sufficient.
5247 If we were to try to guess the arguments, we would probably guess wrong
5248 and then we might not encounter the bug.
5251 A complete input file, or set of input files, that will reproduce the
5252 bug. If the utility is reading an object file or files, then it is
5253 generally most helpful to send the actual object files.
5255 If the source files were produced exclusively using @sc{gnu} programs
5256 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5257 may be OK to send the source files rather than the object files. In
5258 this case, be sure to say exactly what version of @command{gcc}, or
5259 whatever, was used to produce the object files. Also say how
5260 @command{gcc}, or whatever, was configured.
5263 A description of what behavior you observe that you believe is
5264 incorrect. For example, ``It gets a fatal signal.''
5266 Of course, if the bug is that the utility gets a fatal signal, then we
5267 will certainly notice it. But if the bug is incorrect output, we might
5268 not notice unless it is glaringly wrong. You might as well not give us
5269 a chance to make a mistake.
5271 Even if the problem you experience is a fatal signal, you should still
5272 say so explicitly. Suppose something strange is going on, such as your
5273 copy of the utility is out of sync, or you have encountered a bug in
5274 the C library on your system. (This has happened!) Your copy might
5275 crash and ours would not. If you told us to expect a crash, then when
5276 ours fails to crash, we would know that the bug was not happening for
5277 us. If you had not told us to expect a crash, then we would not be able
5278 to draw any conclusion from our observations.
5281 If you wish to suggest changes to the source, send us context diffs, as
5282 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5283 option. Always send diffs from the old file to the new file. If you
5284 wish to discuss something in the @command{ld} source, refer to it by
5285 context, not by line number.
5287 The line numbers in our development sources will not match those in your
5288 sources. Your line numbers would convey no useful information to us.
5291 Here are some things that are not necessary:
5295 A description of the envelope of the bug.
5297 Often people who encounter a bug spend a lot of time investigating
5298 which changes to the input file will make the bug go away and which
5299 changes will not affect it.
5301 This is often time consuming and not very useful, because the way we
5302 will find the bug is by running a single example under the debugger
5303 with breakpoints, not by pure deduction from a series of examples.
5304 We recommend that you save your time for something else.
5306 Of course, if you can find a simpler example to report @emph{instead}
5307 of the original one, that is a convenience for us. Errors in the
5308 output will be easier to spot, running under the debugger will take
5309 less time, and so on.
5311 However, simplification is not vital; if you do not want to do this,
5312 report the bug anyway and send us the entire test case you used.
5315 A patch for the bug.
5317 A patch for the bug does help us if it is a good one. But do not omit
5318 the necessary information, such as the test case, on the assumption that
5319 a patch is all we need. We might see problems with your patch and decide
5320 to fix the problem another way, or we might not understand it at all.
5322 Sometimes with programs as complicated as the binary utilities it is
5323 very hard to construct an example that will make the program follow a
5324 certain path through the code. If you do not send us the example, we
5325 will not be able to construct one, so we will not be able to verify that
5328 And if we cannot understand what bug you are trying to fix, or why your
5329 patch should be an improvement, we will not install it. A test case will
5330 help us to understand.
5333 A guess about what the bug is or what it depends on.
5335 Such guesses are usually wrong. Even we cannot guess right about such
5336 things without first using the debugger to find the facts.
5339 @node GNU Free Documentation License
5340 @appendix GNU Free Documentation License
5344 @node Binutils Index
5345 @unnumbered Binutils Index