1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @settitle @sc{gnu} Binary Utilities
12 @c man begin COPYRIGHT
13 Copyright @copyright{} 1991-2018 Free Software Foundation, Inc.
15 Permission is granted to copy, distribute and/or modify this document
16 under the terms of the GNU Free Documentation License, Version 1.3
17 or any later version published by the Free Software Foundation;
18 with no Invariant Sections, with no Front-Cover Texts, and with no
19 Back-Cover Texts. A copy of the license is included in the
20 section entitled ``GNU Free Documentation License''.
25 @dircategory Software development
27 * Binutils: (binutils). The GNU binary utilities.
30 @dircategory Individual utilities
32 * addr2line: (binutils)addr2line. Convert addresses to file and line.
33 * ar: (binutils)ar. Create, modify, and extract from archives.
34 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols.
35 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt.
36 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs.
37 * nlmconv: (binutils)nlmconv. Converts object code into an NLM.
38 * nm: (binutils)nm. List symbols from object files.
39 * objcopy: (binutils)objcopy. Copy and translate object files.
40 * objdump: (binutils)objdump. Display information from object files.
41 * ranlib: (binutils)ranlib. Generate index to archive contents.
42 * readelf: (binutils)readelf. Display the contents of ELF format files.
43 * size: (binutils)size. List section sizes and total size.
44 * strings: (binutils)strings. List printable strings from files.
45 * strip: (binutils)strip. Discard symbols.
46 * elfedit: (binutils)elfedit. Update the ELF header of ELF files.
47 * windmc: (binutils)windmc. Generator for Windows message resources.
48 * windres: (binutils)windres. Manipulate Windows resources.
52 @title The @sc{gnu} Binary Utilities
53 @ifset VERSION_PACKAGE
54 @subtitle @value{VERSION_PACKAGE}
56 @subtitle Version @value{VERSION}
58 @subtitle @value{UPDATED}
59 @author Roland H. Pesch
60 @author Jeffrey M. Osier
61 @author Cygnus Support
65 {\parskip=0pt \hfill Cygnus Support\par \hfill
66 Texinfo \texinfoversion\par }
69 @vskip 0pt plus 1filll
78 This brief manual contains documentation for the @sc{gnu} binary
80 @ifset VERSION_PACKAGE
81 @value{VERSION_PACKAGE}
83 version @value{VERSION}:
88 Create, modify, and extract from archives
91 List symbols from object files
94 Copy and translate object files
97 Display information from object files
100 Generate index to archive contents
103 Display the contents of ELF format files.
106 List file section sizes and total size
109 List printable strings from files
115 Update the ELF header of ELF files.
118 Demangle encoded C++ symbols (on MS-DOS, this program is named
122 Convert addresses into file names and line numbers
125 Convert object code into a Netware Loadable Module
128 Manipulate Windows resources
131 Generator for Windows message resources
134 Create the files needed to build and use Dynamic Link Libraries
138 This document is distributed under the terms of the GNU Free
139 Documentation License version 1.3. A copy of the license is included
140 in the section entitled ``GNU Free Documentation License''.
143 * ar:: Create, modify, and extract from archives
144 * nm:: List symbols from object files
145 * objcopy:: Copy and translate object files
146 * objdump:: Display information from object files
147 * ranlib:: Generate index to archive contents
148 * size:: List section sizes and total size
149 * strings:: List printable strings from files
150 * strip:: Discard symbols
151 * c++filt:: Filter to demangle encoded C++ symbols
152 * cxxfilt: c++filt. MS-DOS name for c++filt
153 * addr2line:: Convert addresses to file and line
154 * nlmconv:: Converts object code into an NLM
155 * windmc:: Generator for Windows message resources
156 * windres:: Manipulate Windows resources
157 * dlltool:: Create files needed to build and use DLLs
158 * readelf:: Display the contents of ELF format files
159 * elfedit:: Update the ELF header of ELF files
160 * Common Options:: Command-line options for all utilities
161 * Selecting the Target System:: How these utilities determine the target
162 * Reporting Bugs:: Reporting Bugs
163 * GNU Free Documentation License:: GNU Free Documentation License
164 * Binutils Index:: Binutils Index
172 @cindex collections of files
174 @c man title ar create, modify, and extract from archives
177 ar [-]@var{p}[@var{mod}] [@option{--plugin} @var{name}] [@option{--target} @var{bfdname}] [@var{relpos}] [@var{count}] @var{archive} [@var{member}@dots{}]
178 ar -M [ <mri-script ]
181 @c man begin DESCRIPTION ar
183 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
184 archives. An @dfn{archive} is a single file holding a collection of
185 other files in a structure that makes it possible to retrieve
186 the original individual files (called @dfn{members} of the archive).
188 The original files' contents, mode (permissions), timestamp, owner, and
189 group are preserved in the archive, and can be restored on
193 @sc{gnu} @command{ar} can maintain archives whose members have names of any
194 length; however, depending on how @command{ar} is configured on your
195 system, a limit on member-name length may be imposed for compatibility
196 with archive formats maintained with other tools. If it exists, the
197 limit is often 15 characters (typical of formats related to a.out) or 16
198 characters (typical of formats related to coff).
201 @command{ar} is considered a binary utility because archives of this sort
202 are most often used as @dfn{libraries} holding commonly needed
206 @command{ar} creates an index to the symbols defined in relocatable
207 object modules in the archive when you specify the modifier @samp{s}.
208 Once created, this index is updated in the archive whenever @command{ar}
209 makes a change to its contents (save for the @samp{q} update operation).
210 An archive with such an index speeds up linking to the library, and
211 allows routines in the library to call each other without regard to
212 their placement in the archive.
214 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215 table. If an archive lacks the table, another form of @command{ar} called
216 @command{ranlib} can be used to add just the table.
218 @cindex thin archives
219 @sc{gnu} @command{ar} can optionally create a @emph{thin} archive,
220 which contains a symbol index and references to the original copies
221 of the member files of the archive. This is useful for building
222 libraries for use within a local build tree, where the relocatable
223 objects are expected to remain available, and copying the contents of
224 each object would only waste time and space.
226 An archive can either be @emph{thin} or it can be normal. It cannot
227 be both at the same time. Once an archive is created its format
228 cannot be changed without first deleting it and then creating a new
229 archive in its place.
231 Thin archives are also @emph{flattened}, so that adding one thin
232 archive to another thin archive does not nest it, as would happen with
233 a normal archive. Instead the elements of the first archive are added
234 individually to the second archive.
236 The paths to the elements of the archive are stored relative to the
239 @cindex compatibility, @command{ar}
240 @cindex @command{ar} compatibility
241 @sc{gnu} @command{ar} is designed to be compatible with two different
242 facilities. You can control its activity using command-line options,
243 like the different varieties of @command{ar} on Unix systems; or, if you
244 specify the single command-line option @option{-M}, you can control it
245 with a script supplied via standard input, like the MRI ``librarian''
251 * ar cmdline:: Controlling @command{ar} on the command line
252 * ar scripts:: Controlling @command{ar} with a script
257 @section Controlling @command{ar} on the Command Line
260 @c man begin SYNOPSIS ar
261 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{}]
265 @cindex Unix compatibility, @command{ar}
266 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
267 arguments to execute: one keyletter specifying the @emph{operation}
268 (optionally accompanied by other keyletters specifying
269 @emph{modifiers}), and the archive name to act on.
271 Most operations can also accept further @var{member} arguments,
272 specifying particular files to operate on.
274 @c man begin OPTIONS ar
276 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
277 flags @var{mod} in any order, within the first command-line argument.
279 If you wish, you may begin the first command-line argument with a
282 @cindex operations on archive
283 The @var{p} keyletter specifies what operation to execute; it may be
284 any of the following, but you must specify only one of them:
288 @cindex deleting from archive
289 @emph{Delete} modules from the archive. Specify the names of modules to
290 be deleted as @var{member}@dots{}; the archive is untouched if you
291 specify no files to delete.
293 If you specify the @samp{v} modifier, @command{ar} lists each module
297 @cindex moving in archive
298 Use this operation to @emph{move} members in an archive.
300 The ordering of members in an archive can make a difference in how
301 programs are linked using the library, if a symbol is defined in more
304 If no modifiers are used with @code{m}, any members you name in the
305 @var{member} arguments are moved to the @emph{end} of the archive;
306 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
307 specified place instead.
310 @cindex printing from archive
311 @emph{Print} the specified members of the archive, to the standard
312 output file. If the @samp{v} modifier is specified, show the member
313 name before copying its contents to standard output.
315 If you specify no @var{member} arguments, all the files in the archive are
319 @cindex quick append to archive
320 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
321 @var{archive}, without checking for replacement.
323 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
324 operation; new members are always placed at the end of the archive.
326 The modifier @samp{v} makes @command{ar} list each file as it is appended.
328 Since the point of this operation is speed, implementations of
329 @command{ar} have the option of not updating the archive's symbol
330 table if one exists. Too many different systems however assume that
331 symbol tables are always up-to-date, so @sc{gnu} @command{ar} will
332 rebuild the table even with a quick append.
334 Note - @sc{gnu} @command{ar} treats the command @samp{qs} as a
335 synonym for @samp{r} - replacing already existing files in the
336 archive and appending new ones at the end.
339 @cindex replacement in archive
340 Insert the files @var{member}@dots{} into @var{archive} (with
341 @emph{replacement}). This operation differs from @samp{q} in that any
342 previously existing members are deleted if their names match those being
345 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
346 displays an error message, and leaves undisturbed any existing members
347 of the archive matching that name.
349 By default, new members are added at the end of the file; but you may
350 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
351 placement relative to some existing member.
353 The modifier @samp{v} used with this operation elicits a line of
354 output for each file inserted, along with one of the letters @samp{a} or
355 @samp{r} to indicate whether the file was appended (no old member
356 deleted) or replaced.
360 Add an index to the archive, or update it if it already exists. Note
361 this command is an exception to the rule that there can only be one
362 command letter, as it is possible to use it as either a command or a
363 modifier. In either case it does the same thing.
366 @cindex contents of archive
367 Display a @emph{table} listing the contents of @var{archive}, or those
368 of the files listed in @var{member}@dots{} that are present in the
369 archive. Normally only the member name is shown; if you also want to
370 see the modes (permissions), timestamp, owner, group, and size, you can
371 request that by also specifying the @samp{v} modifier.
373 If you do not specify a @var{member}, all files in the archive
376 @cindex repeated names in archive
377 @cindex name duplication in archive
378 If there is more than one file with the same name (say, @samp{fie}) in
379 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
380 first instance; to see them all, you must ask for a complete
381 listing---in our example, @samp{ar t b.a}.
382 @c WRS only; per Gumby, this is implementation-dependent, and in a more
383 @c recent case in fact works the other way.
386 @cindex extract from archive
387 @emph{Extract} members (named @var{member}) from the archive. You can
388 use the @samp{v} modifier with this operation, to request that
389 @command{ar} list each name as it extracts it.
391 If you do not specify a @var{member}, all files in the archive
394 Files cannot be extracted from a thin archive.
397 A number of modifiers (@var{mod}) may immediately follow the @var{p}
398 keyletter, to specify variations on an operation's behavior:
402 @cindex relative placement in archive
403 Add new files @emph{after} an existing member of the
404 archive. If you use the modifier @samp{a}, the name of an existing archive
405 member must be present as the @var{relpos} argument, before the
406 @var{archive} specification.
409 Add new files @emph{before} an existing member of the
410 archive. If you use the modifier @samp{b}, the name of an existing archive
411 member must be present as the @var{relpos} argument, before the
412 @var{archive} specification. (same as @samp{i}).
415 @cindex creating archives
416 @emph{Create} the archive. The specified @var{archive} is always
417 created if it did not exist, when you request an update. But a warning is
418 issued unless you specify in advance that you expect to create it, by
422 @cindex deterministic archives
423 @kindex --enable-deterministic-archives
424 Operate in @emph{deterministic} mode. When adding files and the archive
425 index use zero for UIDs, GIDs, timestamps, and use consistent file modes
426 for all files. When this option is used, if @command{ar} is used with
427 identical options and identical input files, multiple runs will create
428 identical output files regardless of the input files' owners, groups,
429 file modes, or modification times.
431 If @file{binutils} was configured with
432 @option{--enable-deterministic-archives}, then this mode is on by default.
433 It can be disabled with the @samp{U} modifier, below.
436 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
437 names of any length. This will cause it to create archives which are
438 not compatible with the native @command{ar} program on some systems. If
439 this is a concern, the @samp{f} modifier may be used to truncate file
440 names when putting them in the archive.
443 Insert new files @emph{before} an existing member of the
444 archive. If you use the modifier @samp{i}, the name of an existing archive
445 member must be present as the @var{relpos} argument, before the
446 @var{archive} specification. (same as @samp{b}).
449 This modifier is accepted but not used.
450 @c whaffor ar l modifier??? presumably compat; with
451 @c what???---doc@@cygnus.com, 25jan91
454 Uses the @var{count} parameter. This is used if there are multiple
455 entries in the archive with the same name. Extract or delete instance
456 @var{count} of the given name from the archive.
459 @cindex dates in archive
460 Preserve the @emph{original} dates of members when extracting them. If
461 you do not specify this modifier, files extracted from the archive
462 are stamped with the time of extraction.
465 Use the full path name when matching names in the archive. @sc{gnu}
466 @command{ar} can not create an archive with a full path name (such archives
467 are not POSIX complaint), but other archive creators can. This option
468 will cause @sc{gnu} @command{ar} to match file names using a complete path
469 name, which can be convenient when extracting a single file from an
470 archive created by another tool.
473 @cindex writing archive index
474 Write an object-file index into the archive, or update an existing one,
475 even if no other change is made to the archive. You may use this modifier
476 flag either with any operation, or alone. Running @samp{ar s} on an
477 archive is equivalent to running @samp{ranlib} on it.
480 @cindex not writing archive index
481 Do not generate an archive symbol table. This can speed up building a
482 large library in several steps. The resulting archive can not be used
483 with the linker. In order to build a symbol table, you must omit the
484 @samp{S} modifier on the last execution of @samp{ar}, or you must run
485 @samp{ranlib} on the archive.
488 @cindex creating thin archive
489 Make the specified @var{archive} a @emph{thin} archive. If it already
490 exists and is a regular archive, the existing members must be present
491 in the same directory as @var{archive}.
494 @cindex updating an archive
495 Normally, @samp{ar r}@dots{} inserts all files
496 listed into the archive. If you would like to insert @emph{only} those
497 of the files you list that are newer than existing members of the same
498 names, use this modifier. The @samp{u} modifier is allowed only for the
499 operation @samp{r} (replace). In particular, the combination @samp{qu} is
500 not allowed, since checking the timestamps would lose any speed
501 advantage from the operation @samp{q}.
504 @cindex deterministic archives
505 @kindex --enable-deterministic-archives
506 Do @emph{not} operate in @emph{deterministic} mode. This is the inverse
507 of the @samp{D} modifier, above: added files and the archive index will
508 get their actual UID, GID, timestamp, and file mode values.
510 This is the default unless @file{binutils} was configured with
511 @option{--enable-deterministic-archives}.
514 This modifier requests the @emph{verbose} version of an operation. Many
515 operations display additional information, such as filenames processed,
516 when the modifier @samp{v} is appended.
519 This modifier shows the version number of @command{ar}.
522 The @command{ar} program also supports some command line options which
523 are neither modifiers nor actions, but which do change its behaviour
528 Displays the list of command line options supported by @command{ar}
532 Displays the version information of @command{ar} and then exits.
535 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
536 compatibility with AIX. The behaviour produced by this option is the
537 default for @sc{gnu} @command{ar}. @command{ar} does not support any
538 of the other @samp{-X} options; in particular, it does not support
539 @option{-X32} which is the default for AIX @command{ar}.
541 @item --plugin @var{name}
543 The optional command line switch @option{--plugin @var{name}} causes
544 @command{ar} to load the plugin called @var{name} which adds support
545 for more file formats, including object files with link-time
546 optimization information.
548 This option is only available if the toolchain has been built with
549 plugin support enabled.
551 If @option{--plugin} is not provided, but plugin support has been
552 enabled then @command{ar} iterates over the files in
553 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
554 plugin that claims the object in question is used.
556 Please note that this plugin search directory is @emph{not} the one
557 used by @command{ld}'s @option{-plugin} option. In order to make
558 @command{ar} use the linker plugin it must be copied into the
559 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
560 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
561 based compilations it is called @file{LLVMgold.so}. The GCC plugin
562 is always backwards compatible with earlier versions, so it is
563 sufficient to just copy the newest one.
565 @item --target @var{target}
566 The optional command line switch @option{--target @var{bfdname}}
567 specifies that the archive members are in an object code format
568 different from your system's default format. See
569 @xref{Target Selection}, for more information.
574 @c man begin SEEALSO ar
575 nm(1), ranlib(1), and the Info entries for @file{binutils}.
580 @section Controlling @command{ar} with a Script
583 ar -M [ <@var{script} ]
586 @cindex MRI compatibility, @command{ar}
587 @cindex scripts, @command{ar}
588 If you use the single command-line option @samp{-M} with @command{ar}, you
589 can control its operation with a rudimentary command language. This
590 form of @command{ar} operates interactively if standard input is coming
591 directly from a terminal. During interactive use, @command{ar} prompts for
592 input (the prompt is @samp{AR >}), and continues executing even after
593 errors. If you redirect standard input to a script file, no prompts are
594 issued, and @command{ar} abandons execution (with a nonzero exit code)
597 The @command{ar} command language is @emph{not} designed to be equivalent
598 to the command-line options; in fact, it provides somewhat less control
599 over archives. The only purpose of the command language is to ease the
600 transition to @sc{gnu} @command{ar} for developers who already have scripts
601 written for the MRI ``librarian'' program.
603 The syntax for the @command{ar} command language is straightforward:
606 commands are recognized in upper or lower case; for example, @code{LIST}
607 is the same as @code{list}. In the following descriptions, commands are
608 shown in upper case for clarity.
611 a single command may appear on each line; it is the first word on the
615 empty lines are allowed, and have no effect.
618 comments are allowed; text after either of the characters @samp{*}
619 or @samp{;} is ignored.
622 Whenever you use a list of names as part of the argument to an @command{ar}
623 command, you can separate the individual names with either commas or
624 blanks. Commas are shown in the explanations below, for clarity.
627 @samp{+} is used as a line continuation character; if @samp{+} appears
628 at the end of a line, the text on the following line is considered part
629 of the current command.
632 Here are the commands you can use in @command{ar} scripts, or when using
633 @command{ar} interactively. Three of them have special significance:
635 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
636 a temporary file required for most of the other commands.
638 @code{SAVE} commits the changes so far specified by the script. Prior
639 to @code{SAVE}, commands affect only the temporary copy of the current
643 @item ADDLIB @var{archive}
644 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
645 Add all the contents of @var{archive} (or, if specified, each named
646 @var{module} from @var{archive}) to the current archive.
648 Requires prior use of @code{OPEN} or @code{CREATE}.
650 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
651 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
652 @c else like "ar q..."
653 Add each named @var{member} as a module in the current archive.
655 Requires prior use of @code{OPEN} or @code{CREATE}.
658 Discard the contents of the current archive, canceling the effect of
659 any operations since the last @code{SAVE}. May be executed (with no
660 effect) even if no current archive is specified.
662 @item CREATE @var{archive}
663 Creates an archive, and makes it the current archive (required for many
664 other commands). The new archive is created with a temporary name; it
665 is not actually saved as @var{archive} until you use @code{SAVE}.
666 You can overwrite existing archives; similarly, the contents of any
667 existing file named @var{archive} will not be destroyed until @code{SAVE}.
669 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
670 Delete each listed @var{module} from the current archive; equivalent to
671 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
673 Requires prior use of @code{OPEN} or @code{CREATE}.
675 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
676 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
677 List each named @var{module} present in @var{archive}. The separate
678 command @code{VERBOSE} specifies the form of the output: when verbose
679 output is off, output is like that of @samp{ar -t @var{archive}
680 @var{module}@dots{}}. When verbose output is on, the listing is like
681 @samp{ar -tv @var{archive} @var{module}@dots{}}.
683 Output normally goes to the standard output stream; however, if you
684 specify @var{outputfile} as a final argument, @command{ar} directs the
688 Exit from @command{ar}, with a @code{0} exit code to indicate successful
689 completion. This command does not save the output file; if you have
690 changed the current archive since the last @code{SAVE} command, those
693 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
694 Extract each named @var{module} from the current archive, writing them
695 into the current directory as separate files. Equivalent to @samp{ar -x
696 @var{archive} @var{module}@dots{}}.
698 Requires prior use of @code{OPEN} or @code{CREATE}.
701 @c FIXME Tokens but no commands???
708 Display full contents of the current archive, in ``verbose'' style
709 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
710 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
711 enhancement, rather than present for MRI compatibility.)
713 Requires prior use of @code{OPEN} or @code{CREATE}.
715 @item OPEN @var{archive}
716 Opens an existing archive for use as the current archive (required for
717 many other commands). Any changes as the result of subsequent commands
718 will not actually affect @var{archive} until you next use @code{SAVE}.
720 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
721 In the current archive, replace each existing @var{module} (named in
722 the @code{REPLACE} arguments) from files in the current working directory.
723 To execute this command without errors, both the file, and the module in
724 the current archive, must exist.
726 Requires prior use of @code{OPEN} or @code{CREATE}.
729 Toggle an internal flag governing the output from @code{DIRECTORY}.
730 When the flag is on, @code{DIRECTORY} output matches output from
731 @samp{ar -tv }@dots{}.
734 Commit your changes to the current archive, and actually save it as a
735 file with the name specified in the last @code{CREATE} or @code{OPEN}
738 Requires prior use of @code{OPEN} or @code{CREATE}.
747 The @sc{gnu} linker @command{ld} is now described in a separate manual.
748 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
756 @c man title nm list symbols from object files
759 @c man begin SYNOPSIS nm
760 nm [@option{-A}|@option{-o}|@option{--print-file-name}] [@option{-a}|@option{--debug-syms}]
761 [@option{-B}|@option{--format=bsd}] [@option{-C}|@option{--demangle}[=@var{style}]]
762 [@option{-D}|@option{--dynamic}] [@option{-f}@var{format}|@option{--format=}@var{format}]
763 [@option{-g}|@option{--extern-only}] [@option{-h}|@option{--help}]
764 [@option{-l}|@option{--line-numbers}] [@option{--inlines}]
765 [@option{-n}|@option{-v}|@option{--numeric-sort}]
766 [@option{-P}|@option{--portability}] [@option{-p}|@option{--no-sort}]
767 [@option{-r}|@option{--reverse-sort}] [@option{-S}|@option{--print-size}]
768 [@option{-s}|@option{--print-armap}] [@option{-t} @var{radix}|@option{--radix=}@var{radix}]
769 [@option{-u}|@option{--undefined-only}] [@option{-V}|@option{--version}]
770 [@option{-X 32_64}] [@option{--defined-only}] [@option{--no-demangle}]
771 [@option{--plugin} @var{name}] [@option{--size-sort}] [@option{--special-syms}]
772 [@option{--synthetic}] [@option{--with-symbol-versions}] [@option{--target=}@var{bfdname}]
773 [@var{objfile}@dots{}]
777 @c man begin DESCRIPTION nm
778 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
779 If no object files are listed as arguments, @command{nm} assumes the file
782 For each symbol, @command{nm} shows:
786 The symbol value, in the radix selected by options (see below), or
787 hexadecimal by default.
790 The symbol type. At least the following types are used; others are, as
791 well, depending on the object file format. If lowercase, the symbol is
792 usually local; if uppercase, the symbol is global (external). There
793 are however a few lowercase symbols that are shown for special global
794 symbols (@code{u}, @code{v} and @code{w}).
796 @c Some more detail on exactly what these symbol types are used for
800 The symbol's value is absolute, and will not be changed by further
805 The symbol is in the BSS data section. This section typically
806 contains zero-initialized or uninitialized data, although the exact
807 behavior is system dependent.
810 The symbol is common. Common symbols are uninitialized data. When
811 linking, multiple common symbols may appear with the same name. If the
812 symbol is defined anywhere, the common symbols are treated as undefined
815 For more details on common symbols, see the discussion of
816 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
821 The symbol is in the initialized data section.
825 The symbol is in an initialized data section for small objects. Some
826 object file formats permit more efficient access to small data objects,
827 such as a global int variable as opposed to a large global array.
830 For PE format files this indicates that the symbol is in a section
831 specific to the implementation of DLLs. For ELF format files this
832 indicates that the symbol is an indirect function. This is a GNU
833 extension to the standard set of ELF symbol types. It indicates a
834 symbol which if referenced by a relocation does not evaluate to its
835 address, but instead must be invoked at runtime. The runtime
836 execution will then return the value to be used in the relocation.
839 The symbol is an indirect reference to another symbol.
842 The symbol is a debugging symbol.
845 The symbols is in a stack unwind section.
849 The symbol is in a read only data section.
853 The symbol is in an uninitialized or zero-initialized data section
858 The symbol is in the text (code) section.
861 The symbol is undefined.
864 The symbol is a unique global symbol. This is a GNU extension to the
865 standard set of ELF symbol bindings. For such a symbol the dynamic linker
866 will make sure that in the entire process there is just one symbol with
867 this name and type in use.
871 The symbol is a weak object. When a weak defined symbol is linked with
872 a normal defined symbol, the normal defined symbol is used with no error.
873 When a weak undefined symbol is linked and the symbol is not defined,
874 the value of the weak symbol becomes zero with no error. On some
875 systems, uppercase indicates that a default value has been specified.
879 The symbol is a weak symbol that has not been specifically tagged as a
880 weak object symbol. When a weak defined symbol is linked with a normal
881 defined symbol, the normal defined symbol is used with no error.
882 When a weak undefined symbol is linked and the symbol is not defined,
883 the value of the symbol is determined in a system-specific manner without
884 error. On some systems, uppercase indicates that a default value has been
888 The symbol is a stabs symbol in an a.out object file. In this case, the
889 next values printed are the stabs other field, the stabs desc field, and
890 the stab type. Stabs symbols are used to hold debugging information.
893 The symbol type is unknown, or object file format specific.
902 @c man begin OPTIONS nm
903 The long and short forms of options, shown here as alternatives, are
909 @itemx --print-file-name
910 @cindex input file name
912 @cindex source file name
913 Precede each symbol by the name of the input file (or archive member)
914 in which it was found, rather than identifying the input file once only,
915 before all of its symbols.
919 @cindex debugging symbols
920 Display all symbols, even debugger-only symbols; normally these are not
924 @cindex @command{nm} format
925 @cindex @command{nm} compatibility
926 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
929 @itemx --demangle[=@var{style}]
930 @cindex demangling in nm
931 Decode (@dfn{demangle}) low-level symbol names into user-level names.
932 Besides removing any initial underscore prepended by the system, this
933 makes C++ function names readable. Different compilers have different
934 mangling styles. The optional demangling style argument can be used to
935 choose an appropriate demangling style for your compiler. @xref{c++filt},
936 for more information on demangling.
939 Do not demangle low-level symbol names. This is the default.
943 @cindex dynamic symbols
944 Display the dynamic symbols rather than the normal symbols. This is
945 only meaningful for dynamic objects, such as certain types of shared
948 @item -f @var{format}
949 @itemx --format=@var{format}
950 @cindex @command{nm} format
951 @cindex @command{nm} compatibility
952 Use the output format @var{format}, which can be @code{bsd},
953 @code{sysv}, or @code{posix}. The default is @code{bsd}.
954 Only the first character of @var{format} is significant; it can be
955 either upper or lower case.
959 @cindex external symbols
960 Display only external symbols.
964 Show a summary of the options to @command{nm} and exit.
967 @itemx --line-numbers
968 @cindex symbol line numbers
969 For each symbol, use debugging information to try to find a filename and
970 line number. For a defined symbol, look for the line number of the
971 address of the symbol. For an undefined symbol, look for the line
972 number of a relocation entry which refers to the symbol. If line number
973 information can be found, print it after the other symbol information.
976 @cindex objdump inlines
977 When option @option{-l} is active, if the address belongs to a
978 function that was inlined, then this option causes the source
979 information for all enclosing scopes back to the first non-inlined
980 function to be printed as well. For example, if @code{main} inlines
981 @code{callee1} which inlines @code{callee2}, and address is from
982 @code{callee2}, the source information for @code{callee1} and @code{main}
983 will also be printed.
987 @itemx --numeric-sort
988 Sort symbols numerically by their addresses, rather than alphabetically
993 @cindex sorting symbols
994 Do not bother to sort the symbols in any order; print them in the order
999 Use the POSIX.2 standard output format instead of the default format.
1000 Equivalent to @samp{-f posix}.
1003 @itemx --reverse-sort
1004 Reverse the order of the sort (whether numeric or alphabetic); let the
1009 Print both value and size of defined symbols for the @code{bsd} output style.
1010 This option has no effect for object formats that do not record symbol
1011 sizes, unless @samp{--size-sort} is also used in which case a
1012 calculated size is displayed.
1015 @itemx --print-armap
1016 @cindex symbol index, listing
1017 When listing symbols from archive members, include the index: a mapping
1018 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
1019 contain definitions for which names.
1021 @item -t @var{radix}
1022 @itemx --radix=@var{radix}
1023 Use @var{radix} as the radix for printing the symbol values. It must be
1024 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
1027 @itemx --undefined-only
1028 @cindex external symbols
1029 @cindex undefined symbols
1030 Display only undefined symbols (those external to each object file).
1034 Show the version number of @command{nm} and exit.
1037 This option is ignored for compatibility with the AIX version of
1038 @command{nm}. It takes one parameter which must be the string
1039 @option{32_64}. The default mode of AIX @command{nm} corresponds
1040 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
1042 @item --defined-only
1043 @cindex external symbols
1044 @cindex undefined symbols
1045 Display only defined symbols for each object file.
1047 @item --plugin @var{name}
1049 Load the plugin called @var{name} to add support for extra target
1050 types. This option is only available if the toolchain has been built
1051 with plugin support enabled.
1053 If @option{--plugin} is not provided, but plugin support has been
1054 enabled then @command{nm} iterates over the files in
1055 @file{$@{libdir@}/bfd-plugins} in alphabetic order and the first
1056 plugin that claims the object in question is used.
1058 Please note that this plugin search directory is @emph{not} the one
1059 used by @command{ld}'s @option{-plugin} option. In order to make
1060 @command{nm} use the linker plugin it must be copied into the
1061 @file{$@{libdir@}/bfd-plugins} directory. For GCC based compilations
1062 the linker plugin is called @file{liblto_plugin.so.0.0.0}. For Clang
1063 based compilations it is called @file{LLVMgold.so}. The GCC plugin
1064 is always backwards compatible with earlier versions, so it is
1065 sufficient to just copy the newest one.
1068 Sort symbols by size. For ELF objects symbol sizes are read from the
1069 ELF, for other object types the symbol sizes are computed as the
1070 difference between the value of the symbol and the value of the symbol
1071 with the next higher value. If the @code{bsd} output format is used
1072 the size of the symbol is printed, rather than the value, and
1073 @samp{-S} must be used in order both size and value to be printed.
1075 @item --special-syms
1076 Display symbols which have a target-specific special meaning. These
1077 symbols are usually used by the target for some special processing and
1078 are not normally helpful when included in the normal symbol lists.
1079 For example for ARM targets this option would skip the mapping symbols
1080 used to mark transitions between ARM code, THUMB code and data.
1083 Include synthetic symbols in the output. These are special symbols
1084 created by the linker for various purposes. They are not shown by
1085 default since they are not part of the binary's original source code.
1087 @item --with-symbol-versions
1088 Enables the display of symbol version information if any exists. The
1089 version string is displayed as a suffix to the symbol name, preceeded by
1090 an @@ character. For example @samp{foo@@VER_1}. If the version is
1091 the default version to be used when resolving unversioned references
1092 to the symbol then it is displayed as a suffix preceeded by two @@
1093 characters. For example @samp{foo@@@@VER_2}.
1095 @item --target=@var{bfdname}
1096 @cindex object code format
1097 Specify an object code format other than your system's default format.
1098 @xref{Target Selection}, for more information.
1105 @c man begin SEEALSO nm
1106 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
1113 @c man title objcopy copy and translate object files
1116 @c man begin SYNOPSIS objcopy
1117 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
1118 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
1119 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
1120 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
1121 [@option{-S}|@option{--strip-all}]
1122 [@option{-g}|@option{--strip-debug}]
1123 [@option{--strip-unneeded}]
1124 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
1125 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
1126 [@option{--strip-unneeded-symbol=}@var{symbolname}]
1127 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
1128 [@option{--localize-hidden}]
1129 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
1130 [@option{--globalize-symbol=}@var{symbolname}]
1131 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
1132 [@option{-w}|@option{--wildcard}]
1133 [@option{-x}|@option{--discard-all}]
1134 [@option{-X}|@option{--discard-locals}]
1135 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
1136 [@option{-i} [@var{breadth}]|@option{--interleave}[=@var{breadth}]]
1137 [@option{--interleave-width=}@var{width}]
1138 [@option{-j} @var{sectionpattern}|@option{--only-section=}@var{sectionpattern}]
1139 [@option{-R} @var{sectionpattern}|@option{--remove-section=}@var{sectionpattern}]
1140 [@option{--remove-relocations=}@var{sectionpattern}]
1141 [@option{-p}|@option{--preserve-dates}]
1142 [@option{-D}|@option{--enable-deterministic-archives}]
1143 [@option{-U}|@option{--disable-deterministic-archives}]
1144 [@option{--debugging}]
1145 [@option{--gap-fill=}@var{val}]
1146 [@option{--pad-to=}@var{address}]
1147 [@option{--set-start=}@var{val}]
1148 [@option{--adjust-start=}@var{incr}]
1149 [@option{--change-addresses=}@var{incr}]
1150 [@option{--change-section-address} @var{sectionpattern}@{=,+,-@}@var{val}]
1151 [@option{--change-section-lma} @var{sectionpattern}@{=,+,-@}@var{val}]
1152 [@option{--change-section-vma} @var{sectionpattern}@{=,+,-@}@var{val}]
1153 [@option{--change-warnings}] [@option{--no-change-warnings}]
1154 [@option{--set-section-flags} @var{sectionpattern}=@var{flags}]
1155 [@option{--add-section} @var{sectionname}=@var{filename}]
1156 [@option{--dump-section} @var{sectionname}=@var{filename}]
1157 [@option{--update-section} @var{sectionname}=@var{filename}]
1158 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1159 [@option{--long-section-names} @{enable,disable,keep@}]
1160 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1161 [@option{--reverse-bytes=}@var{num}]
1162 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1163 [@option{--redefine-sym} @var{old}=@var{new}]
1164 [@option{--redefine-syms=}@var{filename}]
1166 [@option{--keep-symbols=}@var{filename}]
1167 [@option{--strip-symbols=}@var{filename}]
1168 [@option{--strip-unneeded-symbols=}@var{filename}]
1169 [@option{--keep-global-symbols=}@var{filename}]
1170 [@option{--localize-symbols=}@var{filename}]
1171 [@option{--globalize-symbols=}@var{filename}]
1172 [@option{--weaken-symbols=}@var{filename}]
1173 [@option{--add-symbol} @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1174 [@option{--alt-machine-code=}@var{index}]
1175 [@option{--prefix-symbols=}@var{string}]
1176 [@option{--prefix-sections=}@var{string}]
1177 [@option{--prefix-alloc-sections=}@var{string}]
1178 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1179 [@option{--keep-file-symbols}]
1180 [@option{--only-keep-debug}]
1181 [@option{--strip-dwo}]
1182 [@option{--extract-dwo}]
1183 [@option{--extract-symbol}]
1184 [@option{--writable-text}]
1185 [@option{--readonly-text}]
1188 [@option{--file-alignment=}@var{num}]
1189 [@option{--heap=}@var{size}]
1190 [@option{--image-base=}@var{address}]
1191 [@option{--section-alignment=}@var{num}]
1192 [@option{--stack=}@var{size}]
1193 [@option{--subsystem=}@var{which}:@var{major}.@var{minor}]
1194 [@option{--compress-debug-sections}]
1195 [@option{--decompress-debug-sections}]
1196 [@option{--elf-stt-common=@var{val}}]
1197 [@option{--merge-notes}]
1198 [@option{--no-merge-notes}]
1199 [@option{-v}|@option{--verbose}]
1200 [@option{-V}|@option{--version}]
1201 [@option{--help}] [@option{--info}]
1202 @var{infile} [@var{outfile}]
1206 @c man begin DESCRIPTION objcopy
1207 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1208 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1209 read and write the object files. It can write the destination object
1210 file in a format different from that of the source object file. The
1211 exact behavior of @command{objcopy} is controlled by command-line options.
1212 Note that @command{objcopy} should be able to copy a fully linked file
1213 between any two formats. However, copying a relocatable object file
1214 between any two formats may not work as expected.
1216 @command{objcopy} creates temporary files to do its translations and
1217 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1218 translation work; it has access to all the formats described in @sc{bfd}
1219 and thus is able to recognize most formats without being told
1220 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1222 @command{objcopy} can be used to generate S-records by using an output
1223 target of @samp{srec} (e.g., use @samp{-O srec}).
1225 @command{objcopy} can be used to generate a raw binary file by using an
1226 output target of @samp{binary} (e.g., use @option{-O binary}). When
1227 @command{objcopy} generates a raw binary file, it will essentially produce
1228 a memory dump of the contents of the input object file. All symbols and
1229 relocation information will be discarded. The memory dump will start at
1230 the load address of the lowest section copied into the output file.
1232 When generating an S-record or a raw binary file, it may be helpful to
1233 use @option{-S} to remove sections containing debugging information. In
1234 some cases @option{-R} will be useful to remove sections which contain
1235 information that is not needed by the binary file.
1237 Note---@command{objcopy} is not able to change the endianness of its input
1238 files. If the input format has an endianness (some formats do not),
1239 @command{objcopy} can only copy the inputs into file formats that have the
1240 same endianness or which have no endianness (e.g., @samp{srec}).
1241 (However, see the @option{--reverse-bytes} option.)
1245 @c man begin OPTIONS objcopy
1249 @itemx @var{outfile}
1250 The input and output files, respectively.
1251 If you do not specify @var{outfile}, @command{objcopy} creates a
1252 temporary file and destructively renames the result with
1253 the name of @var{infile}.
1255 @item -I @var{bfdname}
1256 @itemx --input-target=@var{bfdname}
1257 Consider the source file's object format to be @var{bfdname}, rather than
1258 attempting to deduce it. @xref{Target Selection}, for more information.
1260 @item -O @var{bfdname}
1261 @itemx --output-target=@var{bfdname}
1262 Write the output file using the object format @var{bfdname}.
1263 @xref{Target Selection}, for more information.
1265 @item -F @var{bfdname}
1266 @itemx --target=@var{bfdname}
1267 Use @var{bfdname} as the object format for both the input and the output
1268 file; i.e., simply transfer data from source to destination with no
1269 translation. @xref{Target Selection}, for more information.
1271 @item -B @var{bfdarch}
1272 @itemx --binary-architecture=@var{bfdarch}
1273 Useful when transforming a architecture-less input file into an object file.
1274 In this case the output architecture can be set to @var{bfdarch}. This
1275 option will be ignored if the input file has a known @var{bfdarch}. You
1276 can access this binary data inside a program by referencing the special
1277 symbols that are created by the conversion process. These symbols are
1278 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1279 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1280 an object file and then access it in your code using these symbols.
1282 @item -j @var{sectionpattern}
1283 @itemx --only-section=@var{sectionpattern}
1284 Copy only the indicated sections from the input file to the output file.
1285 This option may be given more than once. Note that using this option
1286 inappropriately may make the output file unusable. Wildcard
1287 characters are accepted in @var{sectionpattern}.
1289 If the first character of @var{sectionpattern} is the exclamation
1290 point (!) then matching sections will not be copied, even if earlier
1291 use of @option{--only-section} on the same command line would
1292 otherwise copy it. For example:
1295 --only-section=.text.* --only-section=!.text.foo
1298 will copy all sectinos maching '.text.*' but not the section
1301 @item -R @var{sectionpattern}
1302 @itemx --remove-section=@var{sectionpattern}
1303 Remove any section matching @var{sectionpattern} from the output file.
1304 This option may be given more than once. Note that using this option
1305 inappropriately may make the output file unusable. Wildcard
1306 characters are accepted in @var{sectionpattern}. Using both the
1307 @option{-j} and @option{-R} options together results in undefined
1310 If the first character of @var{sectionpattern} is the exclamation
1311 point (!) then matching sections will not be removed even if an
1312 earlier use of @option{--remove-section} on the same command line
1313 would otherwise remove it. For example:
1316 --remove-section=.text.* --remove-section=!.text.foo
1319 will remove all sections matching the pattern '.text.*', but will not
1320 remove the section '.text.foo'.
1322 @item --remove-relocations=@var{sectionpattern}
1323 Remove relocations from the output file for any section matching
1324 @var{sectionpattern}. This option may be given more than once. Note
1325 that using this option inappropriately may make the output file
1326 unusable. Wildcard characters are accepted in @var{sectionpattern}.
1330 --remove-relocations=.text.*
1333 will remove the relocations for all sections matching the patter
1336 If the first character of @var{sectionpattern} is the exclamation
1337 point (!) then matching sections will not have their relocation
1338 removed even if an earlier use of @option{--remove-relocations} on the
1339 same command line would otherwise cause the relocations to be removed.
1343 --remove-relocations=.text.* --remove-relocations=!.text.foo
1346 will remove all relocations for sections matching the pattern
1347 '.text.*', but will not remove relocations for the section
1352 Do not copy relocation and symbol information from the source file.
1355 @itemx --strip-debug
1356 Do not copy debugging symbols or sections from the source file.
1358 @item --strip-unneeded
1359 Strip all symbols that are not needed for relocation processing.
1361 @item -K @var{symbolname}
1362 @itemx --keep-symbol=@var{symbolname}
1363 When stripping symbols, keep symbol @var{symbolname} even if it would
1364 normally be stripped. This option may be given more than once.
1366 @item -N @var{symbolname}
1367 @itemx --strip-symbol=@var{symbolname}
1368 Do not copy symbol @var{symbolname} from the source file. This option
1369 may be given more than once.
1371 @item --strip-unneeded-symbol=@var{symbolname}
1372 Do not copy symbol @var{symbolname} from the source file unless it is needed
1373 by a relocation. This option may be given more than once.
1375 @item -G @var{symbolname}
1376 @itemx --keep-global-symbol=@var{symbolname}
1377 Keep only symbol @var{symbolname} global. Make all other symbols local
1378 to the file, so that they are not visible externally. This option may
1379 be given more than once.
1381 @item --localize-hidden
1382 In an ELF object, mark all symbols that have hidden or internal visibility
1383 as local. This option applies on top of symbol-specific localization options
1384 such as @option{-L}.
1386 @item -L @var{symbolname}
1387 @itemx --localize-symbol=@var{symbolname}
1388 Convert a global or weak symbol called @var{symbolname} into a local
1389 symbol, so that it is not visible externally. This option may be
1390 given more than once. Note - unique symbols are not converted.
1392 @item -W @var{symbolname}
1393 @itemx --weaken-symbol=@var{symbolname}
1394 Make symbol @var{symbolname} weak. This option may be given more than once.
1396 @item --globalize-symbol=@var{symbolname}
1397 Give symbol @var{symbolname} global scoping so that it is visible
1398 outside of the file in which it is defined. This option may be given
1403 Permit regular expressions in @var{symbolname}s used in other command
1404 line options. The question mark (?), asterisk (*), backslash (\) and
1405 square brackets ([]) operators can be used anywhere in the symbol
1406 name. If the first character of the symbol name is the exclamation
1407 point (!) then the sense of the switch is reversed for that symbol.
1414 would cause objcopy to weaken all symbols that start with ``fo''
1415 except for the symbol ``foo''.
1418 @itemx --discard-all
1419 Do not copy non-global symbols from the source file.
1420 @c FIXME any reason to prefer "non-global" to "local" here?
1423 @itemx --discard-locals
1424 Do not copy compiler-generated local symbols.
1425 (These usually start with @samp{L} or @samp{.}.)
1428 @itemx --byte=@var{byte}
1429 If interleaving has been enabled via the @option{--interleave} option
1430 then start the range of bytes to keep at the @var{byte}th byte.
1431 @var{byte} can be in the range from 0 to @var{breadth}-1, where
1432 @var{breadth} is the value given by the @option{--interleave} option.
1434 @item -i [@var{breadth}]
1435 @itemx --interleave[=@var{breadth}]
1436 Only copy a range out of every @var{breadth} bytes. (Header data is
1437 not affected). Select which byte in the range begins the copy with
1438 the @option{--byte} option. Select the width of the range with the
1439 @option{--interleave-width} option.
1441 This option is useful for creating files to program @sc{rom}. It is
1442 typically used with an @code{srec} output target. Note that
1443 @command{objcopy} will complain if you do not specify the
1444 @option{--byte} option as well.
1446 The default interleave breadth is 4, so with @option{--byte} set to 0,
1447 @command{objcopy} would copy the first byte out of every four bytes
1448 from the input to the output.
1450 @item --interleave-width=@var{width}
1451 When used with the @option{--interleave} option, copy @var{width}
1452 bytes at a time. The start of the range of bytes to be copied is set
1453 by the @option{--byte} option, and the extent of the range is set with
1454 the @option{--interleave} option.
1456 The default value for this option is 1. The value of @var{width} plus
1457 the @var{byte} value set by the @option{--byte} option must not exceed
1458 the interleave breadth set by the @option{--interleave} option.
1460 This option can be used to create images for two 16-bit flashes interleaved
1461 in a 32-bit bus by passing @option{-b 0 -i 4 --interleave-width=2}
1462 and @option{-b 2 -i 4 --interleave-width=2} to two @command{objcopy}
1463 commands. If the input was '12345678' then the outputs would be
1464 '1256' and '3478' respectively.
1467 @itemx --preserve-dates
1468 Set the access and modification dates of the output file to be the same
1469 as those of the input file.
1472 @itemx --enable-deterministic-archives
1473 @cindex deterministic archives
1474 @kindex --enable-deterministic-archives
1475 Operate in @emph{deterministic} mode. When copying archive members
1476 and writing the archive index, use zero for UIDs, GIDs, timestamps,
1477 and use consistent file modes for all files.
1479 If @file{binutils} was configured with
1480 @option{--enable-deterministic-archives}, then this mode is on by default.
1481 It can be disabled with the @samp{-U} option, below.
1484 @itemx --disable-deterministic-archives
1485 @cindex deterministic archives
1486 @kindex --enable-deterministic-archives
1487 Do @emph{not} operate in @emph{deterministic} mode. This is the
1488 inverse of the @option{-D} option, above: when copying archive members
1489 and writing the archive index, use their actual UID, GID, timestamp,
1490 and file mode values.
1492 This is the default unless @file{binutils} was configured with
1493 @option{--enable-deterministic-archives}.
1496 Convert debugging information, if possible. This is not the default
1497 because only certain debugging formats are supported, and the
1498 conversion process can be time consuming.
1500 @item --gap-fill @var{val}
1501 Fill gaps between sections with @var{val}. This operation applies to
1502 the @emph{load address} (LMA) of the sections. It is done by increasing
1503 the size of the section with the lower address, and filling in the extra
1504 space created with @var{val}.
1506 @item --pad-to @var{address}
1507 Pad the output file up to the load address @var{address}. This is
1508 done by increasing the size of the last section. The extra space is
1509 filled in with the value specified by @option{--gap-fill} (default zero).
1511 @item --set-start @var{val}
1512 Set the start address of the new file to @var{val}. Not all object file
1513 formats support setting the start address.
1515 @item --change-start @var{incr}
1516 @itemx --adjust-start @var{incr}
1517 @cindex changing start address
1518 Change the start address by adding @var{incr}. Not all object file
1519 formats support setting the start address.
1521 @item --change-addresses @var{incr}
1522 @itemx --adjust-vma @var{incr}
1523 @cindex changing object addresses
1524 Change the VMA and LMA addresses of all sections, as well as the start
1525 address, by adding @var{incr}. Some object file formats do not permit
1526 section addresses to be changed arbitrarily. Note that this does not
1527 relocate the sections; if the program expects sections to be loaded at a
1528 certain address, and this option is used to change the sections such
1529 that they are loaded at a different address, the program may fail.
1531 @item --change-section-address @var{sectionpattern}@{=,+,-@}@var{val}
1532 @itemx --adjust-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1533 @cindex changing section address
1534 Set or change both the VMA address and the LMA address of any section
1535 matching @var{sectionpattern}. If @samp{=} is used, the section
1536 address is set to @var{val}. Otherwise, @var{val} is added to or
1537 subtracted from the section address. See the comments under
1538 @option{--change-addresses}, above. If @var{sectionpattern} does not
1539 match any sections in the input file, a warning will be issued, unless
1540 @option{--no-change-warnings} is used.
1542 @item --change-section-lma @var{sectionpattern}@{=,+,-@}@var{val}
1543 @cindex changing section LMA
1544 Set or change the LMA address of any sections matching
1545 @var{sectionpattern}. The LMA address is the address where the
1546 section will be loaded into memory at program load time. Normally
1547 this is the same as the VMA address, which is the address of the
1548 section at program run time, but on some systems, especially those
1549 where a program is held in ROM, the two can be different. If @samp{=}
1550 is used, the section address is set to @var{val}. Otherwise,
1551 @var{val} is added to or subtracted from the section address. See the
1552 comments under @option{--change-addresses}, above. If
1553 @var{sectionpattern} does not match any sections in the input file, a
1554 warning will be issued, unless @option{--no-change-warnings} is used.
1556 @item --change-section-vma @var{sectionpattern}@{=,+,-@}@var{val}
1557 @cindex changing section VMA
1558 Set or change the VMA address of any section matching
1559 @var{sectionpattern}. The VMA address is the address where the
1560 section will be located once the program has started executing.
1561 Normally this is the same as the LMA address, which is the address
1562 where the section will be loaded into memory, but on some systems,
1563 especially those where a program is held in ROM, the two can be
1564 different. If @samp{=} is used, the section address is set to
1565 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1566 section address. See the comments under @option{--change-addresses},
1567 above. If @var{sectionpattern} does not match any sections in the
1568 input file, a warning will be issued, unless
1569 @option{--no-change-warnings} is used.
1571 @item --change-warnings
1572 @itemx --adjust-warnings
1573 If @option{--change-section-address} or @option{--change-section-lma} or
1574 @option{--change-section-vma} is used, and the section pattern does not
1575 match any sections, issue a warning. This is the default.
1577 @item --no-change-warnings
1578 @itemx --no-adjust-warnings
1579 Do not issue a warning if @option{--change-section-address} or
1580 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1581 if the section pattern does not match any sections.
1583 @item --set-section-flags @var{sectionpattern}=@var{flags}
1584 Set the flags for any sections matching @var{sectionpattern}. The
1585 @var{flags} argument is a comma separated string of flag names. The
1586 recognized names are @samp{alloc}, @samp{contents}, @samp{load},
1587 @samp{noload}, @samp{readonly}, @samp{code}, @samp{data}, @samp{rom},
1588 @samp{share}, and @samp{debug}. You can set the @samp{contents} flag
1589 for a section which does not have contents, but it is not meaningful
1590 to clear the @samp{contents} flag of a section which does have
1591 contents--just remove the section instead. Not all flags are
1592 meaningful for all object file formats.
1594 @item --add-section @var{sectionname}=@var{filename}
1595 Add a new section named @var{sectionname} while copying the file. The
1596 contents of the new section are taken from the file @var{filename}. The
1597 size of the section will be the size of the file. This option only
1598 works on file formats which can support sections with arbitrary names.
1599 Note - it may be necessary to use the @option{--set-section-flags}
1600 option to set the attributes of the newly created section.
1602 @item --dump-section @var{sectionname}=@var{filename}
1603 Place the contents of section named @var{sectionname} into the file
1604 @var{filename}, overwriting any contents that may have been there
1605 previously. This option is the inverse of @option{--add-section}.
1606 This option is similar to the @option{--only-section} option except
1607 that it does not create a formatted file, it just dumps the contents
1608 as raw binary data, without applying any relocations. The option can
1609 be specified more than once.
1611 @item --update-section @var{sectionname}=@var{filename}
1612 Replace the existing contents of a section named @var{sectionname}
1613 with the contents of file @var{filename}. The size of the section
1614 will be adjusted to the size of the file. The section flags for
1615 @var{sectionname} will be unchanged. For ELF format files the section
1616 to segment mapping will also remain unchanged, something which is not
1617 possible using @option{--remove-section} followed by
1618 @option{--add-section}. The option can be specified more than once.
1620 Note - it is possible to use @option{--rename-section} and
1621 @option{--update-section} to both update and rename a section from one
1622 command line. In this case, pass the original section name to
1623 @option{--update-section}, and the original and new section names to
1624 @option{--rename-section}.
1626 @item --add-symbol @var{name}=[@var{section}:]@var{value}[,@var{flags}]
1627 Add a new symbol named @var{name} while copying the file. This option may be
1628 specified multiple times. If the @var{section} is given, the symbol will be
1629 associated with and relative to that section, otherwise it will be an ABS
1630 symbol. Specifying an undefined section will result in a fatal error. There
1631 is no check for the value, it will be taken as specified. Symbol flags can
1632 be specified and not all flags will be meaningful for all object file
1633 formats. By default, the symbol will be global. The special flag
1634 'before=@var{othersym}' will insert the new symbol in front of the specified
1635 @var{othersym}, otherwise the symbol(s) will be added at the end of the
1636 symbol table in the order they appear.
1638 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1639 Rename a section from @var{oldname} to @var{newname}, optionally
1640 changing the section's flags to @var{flags} in the process. This has
1641 the advantage over using a linker script to perform the rename in that
1642 the output stays as an object file and does not become a linked
1645 This option is particularly helpful when the input format is binary,
1646 since this will always create a section called .data. If for example,
1647 you wanted instead to create a section called .rodata containing binary
1648 data you could use the following command line to achieve it:
1651 objcopy -I binary -O <output_format> -B <architecture> \
1652 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1653 <input_binary_file> <output_object_file>
1656 @item --long-section-names @{enable,disable,keep@}
1657 Controls the handling of long section names when processing @code{COFF}
1658 and @code{PE-COFF} object formats. The default behaviour, @samp{keep},
1659 is to preserve long section names if any are present in the input file.
1660 The @samp{enable} and @samp{disable} options forcibly enable or disable
1661 the use of long section names in the output object; when @samp{disable}
1662 is in effect, any long section names in the input object will be truncated.
1663 The @samp{enable} option will only emit long section names if any are
1664 present in the inputs; this is mostly the same as @samp{keep}, but it
1665 is left undefined whether the @samp{enable} option might force the
1666 creation of an empty string table in the output file.
1668 @item --change-leading-char
1669 Some object file formats use special characters at the start of
1670 symbols. The most common such character is underscore, which compilers
1671 often add before every symbol. This option tells @command{objcopy} to
1672 change the leading character of every symbol when it converts between
1673 object file formats. If the object file formats use the same leading
1674 character, this option has no effect. Otherwise, it will add a
1675 character, or remove a character, or change a character, as
1678 @item --remove-leading-char
1679 If the first character of a global symbol is a special symbol leading
1680 character used by the object file format, remove the character. The
1681 most common symbol leading character is underscore. This option will
1682 remove a leading underscore from all global symbols. This can be useful
1683 if you want to link together objects of different file formats with
1684 different conventions for symbol names. This is different from
1685 @option{--change-leading-char} because it always changes the symbol name
1686 when appropriate, regardless of the object file format of the output
1689 @item --reverse-bytes=@var{num}
1690 Reverse the bytes in a section with output contents. A section length must
1691 be evenly divisible by the value given in order for the swap to be able to
1692 take place. Reversing takes place before the interleaving is performed.
1694 This option is used typically in generating ROM images for problematic
1695 target systems. For example, on some target boards, the 32-bit words
1696 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1697 regardless of the CPU byte order. Depending on the programming model, the
1698 endianness of the ROM may need to be modified.
1700 Consider a simple file with a section containing the following eight
1701 bytes: @code{12345678}.
1703 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1704 output file would be ordered @code{21436587}.
1706 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1707 output file would be ordered @code{43218765}.
1709 By using @samp{--reverse-bytes=2} for the above example, followed by
1710 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1711 output file would be ordered @code{34127856}.
1713 @item --srec-len=@var{ival}
1714 Meaningful only for srec output. Set the maximum length of the Srecords
1715 being produced to @var{ival}. This length covers both address, data and
1718 @item --srec-forceS3
1719 Meaningful only for srec output. Avoid generation of S1/S2 records,
1720 creating S3-only record format.
1722 @item --redefine-sym @var{old}=@var{new}
1723 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1724 when one is trying link two things together for which you have no
1725 source, and there are name collisions.
1727 @item --redefine-syms=@var{filename}
1728 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1729 listed in the file @var{filename}. @var{filename} is simply a flat file,
1730 with one symbol pair per line. Line comments may be introduced by the hash
1731 character. This option may be given more than once.
1734 Change all global symbols in the file to be weak. This can be useful
1735 when building an object which will be linked against other objects using
1736 the @option{-R} option to the linker. This option is only effective when
1737 using an object file format which supports weak symbols.
1739 @item --keep-symbols=@var{filename}
1740 Apply @option{--keep-symbol} option to each symbol listed in the file
1741 @var{filename}. @var{filename} is simply a flat file, with one symbol
1742 name per line. Line comments may be introduced by the hash character.
1743 This option may be given more than once.
1745 @item --strip-symbols=@var{filename}
1746 Apply @option{--strip-symbol} option to each symbol listed in the file
1747 @var{filename}. @var{filename} is simply a flat file, with one symbol
1748 name per line. Line comments may be introduced by the hash character.
1749 This option may be given more than once.
1751 @item --strip-unneeded-symbols=@var{filename}
1752 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1753 the file @var{filename}. @var{filename} is simply a flat file, with one
1754 symbol name per line. Line comments may be introduced by the hash
1755 character. This option may be given more than once.
1757 @item --keep-global-symbols=@var{filename}
1758 Apply @option{--keep-global-symbol} option to each symbol listed in the
1759 file @var{filename}. @var{filename} is simply a flat file, with one
1760 symbol name per line. Line comments may be introduced by the hash
1761 character. This option may be given more than once.
1763 @item --localize-symbols=@var{filename}
1764 Apply @option{--localize-symbol} option to each symbol listed in the file
1765 @var{filename}. @var{filename} is simply a flat file, with one symbol
1766 name per line. Line comments may be introduced by the hash character.
1767 This option may be given more than once.
1769 @item --globalize-symbols=@var{filename}
1770 Apply @option{--globalize-symbol} option to each symbol listed in the file
1771 @var{filename}. @var{filename} is simply a flat file, with one symbol
1772 name per line. Line comments may be introduced by the hash character.
1773 This option may be given more than once.
1775 @item --weaken-symbols=@var{filename}
1776 Apply @option{--weaken-symbol} option to each symbol listed in the file
1777 @var{filename}. @var{filename} is simply a flat file, with one symbol
1778 name per line. Line comments may be introduced by the hash character.
1779 This option may be given more than once.
1781 @item --alt-machine-code=@var{index}
1782 If the output architecture has alternate machine codes, use the
1783 @var{index}th code instead of the default one. This is useful in case
1784 a machine is assigned an official code and the tool-chain adopts the
1785 new code, but other applications still depend on the original code
1786 being used. For ELF based architectures if the @var{index}
1787 alternative does not exist then the value is treated as an absolute
1788 number to be stored in the e_machine field of the ELF header.
1790 @item --writable-text
1791 Mark the output text as writable. This option isn't meaningful for all
1792 object file formats.
1794 @item --readonly-text
1795 Make the output text write protected. This option isn't meaningful for all
1796 object file formats.
1799 Mark the output file as demand paged. This option isn't meaningful for all
1800 object file formats.
1803 Mark the output file as impure. This option isn't meaningful for all
1804 object file formats.
1806 @item --prefix-symbols=@var{string}
1807 Prefix all symbols in the output file with @var{string}.
1809 @item --prefix-sections=@var{string}
1810 Prefix all section names in the output file with @var{string}.
1812 @item --prefix-alloc-sections=@var{string}
1813 Prefix all the names of all allocated sections in the output file with
1816 @item --add-gnu-debuglink=@var{path-to-file}
1817 Creates a .gnu_debuglink section which contains a reference to
1818 @var{path-to-file} and adds it to the output file. Note: the file at
1819 @var{path-to-file} must exist. Part of the process of adding the
1820 .gnu_debuglink section involves embedding a checksum of the contents
1821 of the debug info file into the section.
1823 If the debug info file is built in one location but it is going to be
1824 installed at a later time into a different location then do not use
1825 the path to the installed location. The @option{--add-gnu-debuglink}
1826 option will fail because the installed file does not exist yet.
1827 Instead put the debug info file in the current directory and use the
1828 @option{--add-gnu-debuglink} option without any directory components,
1832 objcopy --add-gnu-debuglink=foo.debug
1835 At debug time the debugger will attempt to look for the separate debug
1836 info file in a set of known locations. The exact set of these
1837 locations varies depending upon the distribution being used, but it
1842 @item * The same directory as the executable.
1844 @item * A sub-directory of the directory containing the executable
1847 @item * A global debug directory such as /usr/lib/debug.
1850 As long as the debug info file has been installed into one of these
1851 locations before the debugger is run everything should work
1854 @item --keep-file-symbols
1855 When stripping a file, perhaps with @option{--strip-debug} or
1856 @option{--strip-unneeded}, retain any symbols specifying source file names,
1857 which would otherwise get stripped.
1859 @item --only-keep-debug
1860 Strip a file, removing contents of any sections that would not be
1861 stripped by @option{--strip-debug} and leaving the debugging sections
1862 intact. In ELF files, this preserves all note sections in the output.
1864 Note - the section headers of the stripped sections are preserved,
1865 including their sizes, but the contents of the section are discarded.
1866 The section headers are preserved so that other tools can match up the
1867 debuginfo file with the real executable, even if that executable has
1868 been relocated to a different address space.
1870 The intention is that this option will be used in conjunction with
1871 @option{--add-gnu-debuglink} to create a two part executable. One a
1872 stripped binary which will occupy less space in RAM and in a
1873 distribution and the second a debugging information file which is only
1874 needed if debugging abilities are required. The suggested procedure
1875 to create these files is as follows:
1878 @item Link the executable as normal. Assuming that is is called
1880 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1881 create a file containing the debugging info.
1882 @item Run @code{objcopy --strip-debug foo} to create a
1883 stripped executable.
1884 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1885 to add a link to the debugging info into the stripped executable.
1888 Note---the choice of @code{.dbg} as an extension for the debug info
1889 file is arbitrary. Also the @code{--only-keep-debug} step is
1890 optional. You could instead do this:
1893 @item Link the executable as normal.
1894 @item Copy @code{foo} to @code{foo.full}
1895 @item Run @code{objcopy --strip-debug foo}
1896 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1899 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1900 full executable. It does not have to be a file created by the
1901 @option{--only-keep-debug} switch.
1903 Note---this switch is only intended for use on fully linked files. It
1904 does not make sense to use it on object files where the debugging
1905 information may be incomplete. Besides the gnu_debuglink feature
1906 currently only supports the presence of one filename containing
1907 debugging information, not multiple filenames on a one-per-object-file
1911 Remove the contents of all DWARF .dwo sections, leaving the
1912 remaining debugging sections and all symbols intact.
1913 This option is intended for use by the compiler as part of
1914 the @option{-gsplit-dwarf} option, which splits debug information
1915 between the .o file and a separate .dwo file. The compiler
1916 generates all debug information in the same file, then uses
1917 the @option{--extract-dwo} option to copy the .dwo sections to
1918 the .dwo file, then the @option{--strip-dwo} option to remove
1919 those sections from the original .o file.
1922 Extract the contents of all DWARF .dwo sections. See the
1923 @option{--strip-dwo} option for more information.
1925 @item --file-alignment @var{num}
1926 Specify the file alignment. Sections in the file will always begin at
1927 file offsets which are multiples of this number. This defaults to
1929 [This option is specific to PE targets.]
1931 @item --heap @var{reserve}
1932 @itemx --heap @var{reserve},@var{commit}
1933 Specify the number of bytes of memory to reserve (and optionally commit)
1934 to be used as heap for this program.
1935 [This option is specific to PE targets.]
1937 @item --image-base @var{value}
1938 Use @var{value} as the base address of your program or dll. This is
1939 the lowest memory location that will be used when your program or dll
1940 is loaded. To reduce the need to relocate and improve performance of
1941 your dlls, each should have a unique base address and not overlap any
1942 other dlls. The default is 0x400000 for executables, and 0x10000000
1944 [This option is specific to PE targets.]
1946 @item --section-alignment @var{num}
1947 Sets the section alignment. Sections in memory will always begin at
1948 addresses which are a multiple of this number. Defaults to 0x1000.
1949 [This option is specific to PE targets.]
1951 @item --stack @var{reserve}
1952 @itemx --stack @var{reserve},@var{commit}
1953 Specify the number of bytes of memory to reserve (and optionally commit)
1954 to be used as stack for this program.
1955 [This option is specific to PE targets.]
1957 @item --subsystem @var{which}
1958 @itemx --subsystem @var{which}:@var{major}
1959 @itemx --subsystem @var{which}:@var{major}.@var{minor}
1960 Specifies the subsystem under which your program will execute. The
1961 legal values for @var{which} are @code{native}, @code{windows},
1962 @code{console}, @code{posix}, @code{efi-app}, @code{efi-bsd},
1963 @code{efi-rtd}, @code{sal-rtd}, and @code{xbox}. You may optionally set
1964 the subsystem version also. Numeric values are also accepted for
1966 [This option is specific to PE targets.]
1968 @item --extract-symbol
1969 Keep the file's section flags and symbols but remove all section data.
1970 Specifically, the option:
1973 @item removes the contents of all sections;
1974 @item sets the size of every section to zero; and
1975 @item sets the file's start address to zero.
1978 This option is used to build a @file{.sym} file for a VxWorks kernel.
1979 It can also be a useful way of reducing the size of a @option{--just-symbols}
1982 @item --compress-debug-sections
1983 Compress DWARF debug sections using zlib with SHF_COMPRESSED from the
1984 ELF ABI. Note - if compression would actually make a section
1985 @emph{larger}, then it is not compressed.
1987 @item --compress-debug-sections=none
1988 @itemx --compress-debug-sections=zlib
1989 @itemx --compress-debug-sections=zlib-gnu
1990 @itemx --compress-debug-sections=zlib-gabi
1991 For ELF files, these options control how DWARF debug sections are
1992 compressed. @option{--compress-debug-sections=none} is equivalent
1993 to @option{--decompress-debug-sections}.
1994 @option{--compress-debug-sections=zlib} and
1995 @option{--compress-debug-sections=zlib-gabi} are equivalent to
1996 @option{--compress-debug-sections}.
1997 @option{--compress-debug-sections=zlib-gnu} compresses DWARF debug
1998 sections using zlib. The debug sections are renamed to begin with
1999 @samp{.zdebug} instead of @samp{.debug}. Note - if compression would
2000 actually make a section @emph{larger}, then it is not compressed nor
2003 @item --decompress-debug-sections
2004 Decompress DWARF debug sections using zlib. The original section
2005 names of the compressed sections are restored.
2007 @item --elf-stt-common=yes
2008 @itemx --elf-stt-common=no
2009 For ELF files, these options control whether common symbols should be
2010 converted to the @code{STT_COMMON} or @code{STT_OBJECT} type.
2011 @option{--elf-stt-common=yes} converts common symbol type to
2012 @code{STT_COMMON}. @option{--elf-stt-common=no} converts common symbol
2013 type to @code{STT_OBJECT}.
2016 @itemx --no-merge-notes
2017 For ELF files, attempt (or do not attempt) to reduce the size of any
2018 SHT_NOTE type sections by removing duplicate notes.
2022 Show the version number of @command{objcopy}.
2026 Verbose output: list all object files modified. In the case of
2027 archives, @samp{objcopy -V} lists all members of the archive.
2030 Show a summary of the options to @command{objcopy}.
2033 Display a list showing all architectures and object formats available.
2039 @c man begin SEEALSO objcopy
2040 ld(1), objdump(1), and the Info entries for @file{binutils}.
2047 @cindex object file information
2050 @c man title objdump display information from object files.
2053 @c man begin SYNOPSIS objdump
2054 objdump [@option{-a}|@option{--archive-headers}]
2055 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
2056 [@option{-C}|@option{--demangle}[=@var{style}] ]
2057 [@option{-d}|@option{--disassemble}]
2058 [@option{-D}|@option{--disassemble-all}]
2059 [@option{-z}|@option{--disassemble-zeroes}]
2060 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
2061 [@option{-f}|@option{--file-headers}]
2062 [@option{-F}|@option{--file-offsets}]
2063 [@option{--file-start-context}]
2064 [@option{-g}|@option{--debugging}]
2065 [@option{-e}|@option{--debugging-tags}]
2066 [@option{-h}|@option{--section-headers}|@option{--headers}]
2067 [@option{-i}|@option{--info}]
2068 [@option{-j} @var{section}|@option{--section=}@var{section}]
2069 [@option{-l}|@option{--line-numbers}]
2070 [@option{-S}|@option{--source}]
2071 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
2072 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
2073 [@option{-p}|@option{--private-headers}]
2074 [@option{-P} @var{options}|@option{--private=}@var{options}]
2075 [@option{-r}|@option{--reloc}]
2076 [@option{-R}|@option{--dynamic-reloc}]
2077 [@option{-s}|@option{--full-contents}]
2078 [@option{-W[lLiaprmfFsoRtUuTgAckK]}|
2079 @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]
2080 [@option{-G}|@option{--stabs}]
2081 [@option{-t}|@option{--syms}]
2082 [@option{-T}|@option{--dynamic-syms}]
2083 [@option{-x}|@option{--all-headers}]
2084 [@option{-w}|@option{--wide}]
2085 [@option{--start-address=}@var{address}]
2086 [@option{--stop-address=}@var{address}]
2087 [@option{--prefix-addresses}]
2088 [@option{--[no-]show-raw-insn}]
2089 [@option{--adjust-vma=}@var{offset}]
2090 [@option{--dwarf-depth=@var{n}}]
2091 [@option{--dwarf-start=@var{n}}]
2092 [@option{--special-syms}]
2093 [@option{--prefix=}@var{prefix}]
2094 [@option{--prefix-strip=}@var{level}]
2095 [@option{--insn-width=}@var{width}]
2096 [@option{-V}|@option{--version}]
2097 [@option{-H}|@option{--help}]
2098 @var{objfile}@dots{}
2102 @c man begin DESCRIPTION objdump
2104 @command{objdump} displays information about one or more object files.
2105 The options control what particular information to display. This
2106 information is mostly useful to programmers who are working on the
2107 compilation tools, as opposed to programmers who just want their
2108 program to compile and work.
2110 @var{objfile}@dots{} are the object files to be examined. When you
2111 specify archives, @command{objdump} shows information on each of the member
2116 @c man begin OPTIONS objdump
2118 The long and short forms of options, shown here as alternatives, are
2119 equivalent. At least one option from the list
2120 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
2124 @itemx --archive-header
2125 @cindex archive headers
2126 If any of the @var{objfile} files are archives, display the archive
2127 header information (in a format similar to @samp{ls -l}). Besides the
2128 information you could list with @samp{ar tv}, @samp{objdump -a} shows
2129 the object file format of each archive member.
2131 @item --adjust-vma=@var{offset}
2132 @cindex section addresses in objdump
2133 @cindex VMA in objdump
2134 When dumping information, first add @var{offset} to all the section
2135 addresses. This is useful if the section addresses do not correspond to
2136 the symbol table, which can happen when putting sections at particular
2137 addresses when using a format which can not represent section addresses,
2140 @item -b @var{bfdname}
2141 @itemx --target=@var{bfdname}
2142 @cindex object code format
2143 Specify that the object-code format for the object files is
2144 @var{bfdname}. This option may not be necessary; @var{objdump} can
2145 automatically recognize many formats.
2149 objdump -b oasys -m vax -h fu.o
2152 displays summary information from the section headers (@option{-h}) of
2153 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
2154 file in the format produced by Oasys compilers. You can list the
2155 formats available with the @option{-i} option.
2156 @xref{Target Selection}, for more information.
2159 @itemx --demangle[=@var{style}]
2160 @cindex demangling in objdump
2161 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2162 Besides removing any initial underscore prepended by the system, this
2163 makes C++ function names readable. Different compilers have different
2164 mangling styles. The optional demangling style argument can be used to
2165 choose an appropriate demangling style for your compiler. @xref{c++filt},
2166 for more information on demangling.
2170 Display debugging information. This attempts to parse STABS and IEEE
2171 debugging format information stored in the file and print it out using
2172 a C like syntax. If neither of these formats are found this option
2173 falls back on the @option{-W} option to print any DWARF information in
2177 @itemx --debugging-tags
2178 Like @option{-g}, but the information is generated in a format compatible
2182 @itemx --disassemble
2183 @cindex disassembling object code
2184 @cindex machine instructions
2185 Display the assembler mnemonics for the machine instructions from
2186 @var{objfile}. This option only disassembles those sections which are
2187 expected to contain instructions.
2190 @itemx --disassemble-all
2191 Like @option{-d}, but disassemble the contents of all sections, not just
2192 those expected to contain instructions.
2194 This option also has a subtle effect on the disassembly of
2195 instructions in code sections. When option @option{-d} is in effect
2196 objdump will assume that any symbols present in a code section occur
2197 on the boundary between instructions and it will refuse to disassemble
2198 across such a boundary. When option @option{-D} is in effect however
2199 this assumption is supressed. This means that it is possible for the
2200 output of @option{-d} and @option{-D} to differ if, for example, data
2201 is stored in code sections.
2203 If the target is an ARM architecture this switch also has the effect
2204 of forcing the disassembler to decode pieces of data found in code
2205 sections as if they were instructions.
2207 @item --prefix-addresses
2208 When disassembling, print the complete address on each line. This is
2209 the older disassembly format.
2213 @itemx --endian=@{big|little@}
2215 @cindex disassembly endianness
2216 Specify the endianness of the object files. This only affects
2217 disassembly. This can be useful when disassembling a file format which
2218 does not describe endianness information, such as S-records.
2221 @itemx --file-headers
2222 @cindex object file header
2223 Display summary information from the overall header of
2224 each of the @var{objfile} files.
2227 @itemx --file-offsets
2228 @cindex object file offsets
2229 When disassembling sections, whenever a symbol is displayed, also
2230 display the file offset of the region of data that is about to be
2231 dumped. If zeroes are being skipped, then when disassembly resumes,
2232 tell the user how many zeroes were skipped and the file offset of the
2233 location from where the disassembly resumes. When dumping sections,
2234 display the file offset of the location from where the dump starts.
2236 @item --file-start-context
2237 @cindex source code context
2238 Specify that when displaying interlisted source code/disassembly
2239 (assumes @option{-S}) from a file that has not yet been displayed, extend the
2240 context to the start of the file.
2243 @itemx --section-headers
2245 @cindex section headers
2246 Display summary information from the section headers of the
2249 File segments may be relocated to nonstandard addresses, for example by
2250 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
2251 @command{ld}. However, some object file formats, such as a.out, do not
2252 store the starting address of the file segments. In those situations,
2253 although @command{ld} relocates the sections correctly, using @samp{objdump
2254 -h} to list the file section headers cannot show the correct addresses.
2255 Instead, it shows the usual addresses, which are implicit for the
2258 Note, in some cases it is possible for a section to have both the
2259 READONLY and the NOREAD attributes set. In such cases the NOREAD
2260 attribute takes precedence, but @command{objdump} will report both
2261 since the exact setting of the flag bits might be important.
2265 Print a summary of the options to @command{objdump} and exit.
2269 @cindex architectures available
2270 @cindex object formats available
2271 Display a list showing all architectures and object formats available
2272 for specification with @option{-b} or @option{-m}.
2275 @itemx --section=@var{name}
2276 @cindex section information
2277 Display information only for section @var{name}.
2280 @itemx --line-numbers
2281 @cindex source filenames for object files
2282 Label the display (using debugging information) with the filename and
2283 source line numbers corresponding to the object code or relocs shown.
2284 Only useful with @option{-d}, @option{-D}, or @option{-r}.
2286 @item -m @var{machine}
2287 @itemx --architecture=@var{machine}
2288 @cindex architecture
2289 @cindex disassembly architecture
2290 Specify the architecture to use when disassembling object files. This
2291 can be useful when disassembling object files which do not describe
2292 architecture information, such as S-records. You can list the available
2293 architectures with the @option{-i} option.
2295 If the target is an ARM architecture then this switch has an
2296 additional effect. It restricts the disassembly to only those
2297 instructions supported by the architecture specified by @var{machine}.
2298 If it is necessary to use this switch because the input file does not
2299 contain any architecture information, but it is also desired to
2300 disassemble all the instructions use @option{-marm}.
2302 @item -M @var{options}
2303 @itemx --disassembler-options=@var{options}
2304 Pass target specific information to the disassembler. Only supported on
2305 some targets. If it is necessary to specify more than one
2306 disassembler option then multiple @option{-M} options can be used or
2307 can be placed together into a comma separated list.
2309 For ARC, @option{dsp} controls the printing of DSP instructions,
2310 @option{spfp} selects the printing of FPX single precision FP
2311 instructions, @option{dpfp} selects the printing of FPX double
2312 precision FP instructions, @option{quarkse_em} selects the printing of
2313 special QuarkSE-EM instructions, @option{fpuda} selects the printing
2314 of double precision assist instructions, @option{fpus} selects the
2315 printing of FPU single precision FP instructions, while @option{fpud}
2316 selects the printing of FPU souble precision FP instructions.
2317 Additionally, one can choose to have all the immediates printed in
2318 hexadecimal using @option{hex}. By default, the short immediates are
2319 printed using the decimal representation, while the long immediate
2320 values are printed as hexadecimal.
2322 @option{cpu=...} allows to enforce a particular ISA when disassembling
2323 instructions, overriding the @option{-m} value or whatever is in the ELF file.
2324 This might be useful to select ARC EM or HS ISA, because architecture is same
2325 for those and disassembler relies on private ELF header data to decide if code
2326 is for EM or HS. This option might be specified multiple times - only the
2327 latest value will be used. Valid values are same as for the assembler
2328 @option{-mcpu=...} option.
2330 If the target is an ARM architecture then this switch can be used to
2331 select which register name set is used during disassembler. Specifying
2332 @option{-M reg-names-std} (the default) will select the register names as
2333 used in ARM's instruction set documentation, but with register 13 called
2334 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
2335 @option{-M reg-names-apcs} will select the name set used by the ARM
2336 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
2337 just use @samp{r} followed by the register number.
2339 There are also two variants on the APCS register naming scheme enabled
2340 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
2341 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
2342 with the normal register names or the special register names).
2344 This option can also be used for ARM architectures to force the
2345 disassembler to interpret all instructions as Thumb instructions by
2346 using the switch @option{--disassembler-options=force-thumb}. This can be
2347 useful when attempting to disassemble thumb code produced by other
2350 For the x86, some of the options duplicate functions of the @option{-m}
2351 switch, but allow finer grained control. Multiple selections from the
2352 following may be specified as a comma separated string.
2357 Select disassembly for the given architecture.
2361 Select between intel syntax mode and AT&T syntax mode.
2365 Select between AMD64 ISA and Intel64 ISA.
2367 @item intel-mnemonic
2369 Select between intel mnemonic mode and AT&T mnemonic mode.
2370 Note: @code{intel-mnemonic} implies @code{intel} and
2371 @code{att-mnemonic} implies @code{att}.
2378 Specify the default address size and operand size. These four options
2379 will be overridden if @code{x86-64}, @code{i386} or @code{i8086}
2380 appear later in the option string.
2383 When in AT&T mode, instructs the disassembler to print a mnemonic
2384 suffix even when the suffix could be inferred by the operands.
2387 For PowerPC, the @option{-M} argument @option{raw} selects
2388 disasssembly of hardware insns rather than aliases. For example, you
2389 will see @code{rlwinm} rather than @code{clrlwi}, and @code{addi}
2390 rather than @code{li}. All of the @option{-m} arguments for
2391 @command{gas} that select a CPU are supported. These are:
2392 @option{403}, @option{405}, @option{440}, @option{464}, @option{476},
2393 @option{601}, @option{603}, @option{604}, @option{620}, @option{7400},
2394 @option{7410}, @option{7450}, @option{7455}, @option{750cl},
2395 @option{821}, @option{850}, @option{860}, @option{a2}, @option{booke},
2396 @option{booke32}, @option{cell}, @option{com}, @option{e200z4},
2397 @option{e300}, @option{e500}, @option{e500mc}, @option{e500mc64},
2398 @option{e500x2}, @option{e5500}, @option{e6500}, @option{efs},
2399 @option{power4}, @option{power5}, @option{power6}, @option{power7},
2400 @option{power8}, @option{power9}, @option{ppc}, @option{ppc32},
2401 @option{ppc64}, @option{ppc64bridge}, @option{ppcps}, @option{pwr},
2402 @option{pwr2}, @option{pwr4}, @option{pwr5}, @option{pwr5x},
2403 @option{pwr6}, @option{pwr7}, @option{pwr8}, @option{pwr9},
2404 @option{pwrx}, @option{titan}, and @option{vle}.
2405 @option{32} and @option{64} modify the default or a prior CPU
2406 selection, disabling and enabling 64-bit insns respectively. In
2407 addition, @option{altivec}, @option{any}, @option{htm}, @option{vsx},
2408 and @option{spe} add capabilities to a previous @emph{or later} CPU
2409 selection. @option{any} will disassemble any opcode known to
2410 binutils, but in cases where an opcode has two different meanings or
2411 different arguments, you may not see the disassembly you expect.
2412 If you disassemble without giving a CPU selection, a default will be
2413 chosen from information gleaned by BFD from the object files headers,
2414 but the result again may not be as you expect.
2416 For MIPS, this option controls the printing of instruction mnemonic
2417 names and register names in disassembled instructions. Multiple
2418 selections from the following may be specified as a comma separated
2419 string, and invalid options are ignored:
2423 Print the 'raw' instruction mnemonic instead of some pseudo
2424 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
2425 'sll' instead of 'nop', etc.
2428 Disassemble MSA instructions.
2431 Disassemble the virtualization ASE instructions.
2434 Disassemble the eXtended Physical Address (XPA) ASE instructions.
2436 @item gpr-names=@var{ABI}
2437 Print GPR (general-purpose register) names as appropriate
2438 for the specified ABI. By default, GPR names are selected according to
2439 the ABI of the binary being disassembled.
2441 @item fpr-names=@var{ABI}
2442 Print FPR (floating-point register) names as
2443 appropriate for the specified ABI. By default, FPR numbers are printed
2446 @item cp0-names=@var{ARCH}
2447 Print CP0 (system control coprocessor; coprocessor 0) register names
2448 as appropriate for the CPU or architecture specified by
2449 @var{ARCH}. By default, CP0 register names are selected according to
2450 the architecture and CPU of the binary being disassembled.
2452 @item hwr-names=@var{ARCH}
2453 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
2454 as appropriate for the CPU or architecture specified by
2455 @var{ARCH}. By default, HWR names are selected according to
2456 the architecture and CPU of the binary being disassembled.
2458 @item reg-names=@var{ABI}
2459 Print GPR and FPR names as appropriate for the selected ABI.
2461 @item reg-names=@var{ARCH}
2462 Print CPU-specific register names (CP0 register and HWR names)
2463 as appropriate for the selected CPU or architecture.
2466 For any of the options listed above, @var{ABI} or
2467 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
2468 rather than names, for the selected types of registers.
2469 You can list the available values of @var{ABI} and @var{ARCH} using
2470 the @option{--help} option.
2472 For VAX, you can specify function entry addresses with @option{-M
2473 entry:0xf00ba}. You can use this multiple times to properly
2474 disassemble VAX binary files that don't contain symbol tables (like
2475 ROM dumps). In these cases, the function entry mask would otherwise
2476 be decoded as VAX instructions, which would probably lead the rest
2477 of the function being wrongly disassembled.
2480 @itemx --private-headers
2481 Print information that is specific to the object file format. The exact
2482 information printed depends upon the object file format. For some
2483 object file formats, no additional information is printed.
2485 @item -P @var{options}
2486 @itemx --private=@var{options}
2487 Print information that is specific to the object file format. The
2488 argument @var{options} is a comma separated list that depends on the
2489 format (the lists of options is displayed with the help).
2491 For XCOFF, the available options are:
2507 Not all object formats support this option. In particular the ELF
2508 format does not use it.
2512 @cindex relocation entries, in object file
2513 Print the relocation entries of the file. If used with @option{-d} or
2514 @option{-D}, the relocations are printed interspersed with the
2518 @itemx --dynamic-reloc
2519 @cindex dynamic relocation entries, in object file
2520 Print the dynamic relocation entries of the file. This is only
2521 meaningful for dynamic objects, such as certain types of shared
2522 libraries. As for @option{-r}, if used with @option{-d} or
2523 @option{-D}, the relocations are printed interspersed with the
2527 @itemx --full-contents
2528 @cindex sections, full contents
2529 @cindex object file sections
2530 Display the full contents of any sections requested. By default all
2531 non-empty sections are displayed.
2535 @cindex source disassembly
2536 @cindex disassembly, with source
2537 Display source code intermixed with disassembly, if possible. Implies
2540 @item --prefix=@var{prefix}
2541 @cindex Add prefix to absolute paths
2542 Specify @var{prefix} to add to the absolute paths when used with
2545 @item --prefix-strip=@var{level}
2546 @cindex Strip absolute paths
2547 Indicate how many initial directory names to strip off the hardwired
2548 absolute paths. It has no effect without @option{--prefix=}@var{prefix}.
2550 @item --show-raw-insn
2551 When disassembling instructions, print the instruction in hex as well as
2552 in symbolic form. This is the default except when
2553 @option{--prefix-addresses} is used.
2555 @item --no-show-raw-insn
2556 When disassembling instructions, do not print the instruction bytes.
2557 This is the default when @option{--prefix-addresses} is used.
2559 @item --insn-width=@var{width}
2560 @cindex Instruction width
2561 Display @var{width} bytes on a single line when disassembling
2564 @item -W[lLiaprmfFsoRtUuTgAckK]
2565 @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]
2566 @include debug.options.texi
2569 Enable additional checks for consistency of Dwarf information.
2575 @cindex debug symbols
2576 @cindex ELF object file format
2577 Display the full contents of any sections requested. Display the
2578 contents of the .stab and .stab.index and .stab.excl sections from an
2579 ELF file. This is only useful on systems (such as Solaris 2.0) in which
2580 @code{.stab} debugging symbol-table entries are carried in an ELF
2581 section. In most other file formats, debugging symbol-table entries are
2582 interleaved with linkage symbols, and are visible in the @option{--syms}
2585 @item --start-address=@var{address}
2586 @cindex start-address
2587 Start displaying data at the specified address. This affects the output
2588 of the @option{-d}, @option{-r} and @option{-s} options.
2590 @item --stop-address=@var{address}
2591 @cindex stop-address
2592 Stop displaying data at the specified address. This affects the output
2593 of the @option{-d}, @option{-r} and @option{-s} options.
2597 @cindex symbol table entries, printing
2598 Print the symbol table entries of the file.
2599 This is similar to the information provided by the @samp{nm} program,
2600 although the display format is different. The format of the output
2601 depends upon the format of the file being dumped, but there are two main
2602 types. One looks like this:
2605 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
2606 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
2609 where the number inside the square brackets is the number of the entry
2610 in the symbol table, the @var{sec} number is the section number, the
2611 @var{fl} value are the symbol's flag bits, the @var{ty} number is the
2612 symbol's type, the @var{scl} number is the symbol's storage class and
2613 the @var{nx} value is the number of auxilary entries associated with
2614 the symbol. The last two fields are the symbol's value and its name.
2616 The other common output format, usually seen with ELF based files,
2620 00000000 l d .bss 00000000 .bss
2621 00000000 g .text 00000000 fred
2624 Here the first number is the symbol's value (sometimes refered to as
2625 its address). The next field is actually a set of characters and
2626 spaces indicating the flag bits that are set on the symbol. These
2627 characters are described below. Next is the section with which the
2628 symbol is associated or @emph{*ABS*} if the section is absolute (ie
2629 not connected with any section), or @emph{*UND*} if the section is
2630 referenced in the file being dumped, but not defined there.
2632 After the section name comes another field, a number, which for common
2633 symbols is the alignment and for other symbol is the size. Finally
2634 the symbol's name is displayed.
2636 The flag characters are divided into 7 groups as follows:
2642 The symbol is a local (l), global (g), unique global (u), neither
2643 global nor local (a space) or both global and local (!). A
2644 symbol can be neither local or global for a variety of reasons, e.g.,
2645 because it is used for debugging, but it is probably an indication of
2646 a bug if it is ever both local and global. Unique global symbols are
2647 a GNU extension to the standard set of ELF symbol bindings. For such
2648 a symbol the dynamic linker will make sure that in the entire process
2649 there is just one symbol with this name and type in use.
2652 The symbol is weak (w) or strong (a space).
2655 The symbol denotes a constructor (C) or an ordinary symbol (a space).
2658 The symbol is a warning (W) or a normal symbol (a space). A warning
2659 symbol's name is a message to be displayed if the symbol following the
2660 warning symbol is ever referenced.
2664 The symbol is an indirect reference to another symbol (I), a function
2665 to be evaluated during reloc processing (i) or a normal symbol (a
2670 The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2671 normal symbol (a space).
2676 The symbol is the name of a function (F) or a file (f) or an object
2677 (O) or just a normal symbol (a space).
2681 @itemx --dynamic-syms
2682 @cindex dynamic symbol table entries, printing
2683 Print the dynamic symbol table entries of the file. This is only
2684 meaningful for dynamic objects, such as certain types of shared
2685 libraries. This is similar to the information provided by the @samp{nm}
2686 program when given the @option{-D} (@option{--dynamic}) option.
2688 The output format is similar to that produced by the @option{--syms}
2689 option, except that an extra field is inserted before the symbol's
2690 name, giving the version information associated with the symbol.
2691 If the version is the default version to be used when resolving
2692 unversioned references to the symbol then it's displayed as is,
2693 otherwise it's put into parentheses.
2695 @item --special-syms
2696 When displaying symbols include those which the target considers to be
2697 special in some way and which would not normally be of interest to the
2702 Print the version number of @command{objdump} and exit.
2705 @itemx --all-headers
2706 @cindex all header information, object file
2707 @cindex header information, all
2708 Display all available header information, including the symbol table and
2709 relocation entries. Using @option{-x} is equivalent to specifying all of
2710 @option{-a -f -h -p -r -t}.
2714 @cindex wide output, printing
2715 Format some lines for output devices that have more than 80 columns.
2716 Also do not truncate symbol names when they are displayed.
2719 @itemx --disassemble-zeroes
2720 Normally the disassembly output will skip blocks of zeroes. This
2721 option directs the disassembler to disassemble those blocks, just like
2728 @c man begin SEEALSO objdump
2729 nm(1), readelf(1), and the Info entries for @file{binutils}.
2737 @cindex archive contents
2738 @cindex symbol index
2740 @c man title ranlib generate index to archive.
2743 @c man begin SYNOPSIS ranlib
2744 ranlib [@option{--plugin} @var{name}] [@option{-DhHvVt}] @var{archive}
2748 @c man begin DESCRIPTION ranlib
2750 @command{ranlib} generates an index to the contents of an archive and
2751 stores it in the archive. The index lists each symbol defined by a
2752 member of an archive that is a relocatable object file.
2754 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2756 An archive with such an index speeds up linking to the library and
2757 allows routines in the library to call each other without regard to
2758 their placement in the archive.
2760 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2761 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2766 @c man begin OPTIONS ranlib
2772 Show usage information for @command{ranlib}.
2777 Show the version number of @command{ranlib}.
2780 @cindex deterministic archives
2781 @kindex --enable-deterministic-archives
2782 Operate in @emph{deterministic} mode. The symbol map archive member's
2783 header will show zero for the UID, GID, and timestamp. When this
2784 option is used, multiple runs will produce identical output files.
2786 If @file{binutils} was configured with
2787 @option{--enable-deterministic-archives}, then this mode is on by
2788 default. It can be disabled with the @samp{-U} option, described
2792 Update the timestamp of the symbol map of an archive.
2795 @cindex deterministic archives
2796 @kindex --enable-deterministic-archives
2797 Do @emph{not} operate in @emph{deterministic} mode. This is the
2798 inverse of the @samp{-D} option, above: the archive index will get
2799 actual UID, GID, timestamp, and file mode values.
2801 If @file{binutils} was configured @emph{without}
2802 @option{--enable-deterministic-archives}, then this mode is on by
2810 @c man begin SEEALSO ranlib
2811 ar(1), nm(1), and the Info entries for @file{binutils}.
2819 @cindex section sizes
2821 @c man title size list section sizes and total size.
2824 @c man begin SYNOPSIS size
2825 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2827 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2829 [@option{-t}|@option{--totals}]
2830 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2831 [@var{objfile}@dots{}]
2835 @c man begin DESCRIPTION size
2837 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2838 size---for each of the object or archive files @var{objfile} in its
2839 argument list. By default, one line of output is generated for each
2840 object file or each module in an archive.
2842 @var{objfile}@dots{} are the object files to be examined.
2843 If none are specified, the file @code{a.out} will be used.
2847 @c man begin OPTIONS size
2849 The command line options have the following meanings:
2854 @itemx --format=@var{compatibility}
2855 @cindex @command{size} display format
2856 Using one of these options, you can choose whether the output from @sc{gnu}
2857 @command{size} resembles output from System V @command{size} (using @option{-A},
2858 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2859 @option{--format=berkeley}). The default is the one-line format similar to
2861 @c Bonus for doc-source readers: you can also say --format=strange (or
2862 @c anything else that starts with 's') for sysv, and --format=boring (or
2863 @c anything else that starts with 'b') for Berkeley.
2865 Here is an example of the Berkeley (default) format of output from
2868 $ size --format=Berkeley ranlib size
2869 text data bss dec hex filename
2870 294880 81920 11592 388392 5ed28 ranlib
2871 294880 81920 11888 388688 5ee50 size
2875 This is the same data, but displayed closer to System V conventions:
2878 $ size --format=SysV ranlib size
2896 Show a summary of acceptable arguments and options.
2901 @itemx --radix=@var{number}
2902 @cindex @command{size} number format
2903 @cindex radix for section sizes
2904 Using one of these options, you can control whether the size of each
2905 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2906 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2907 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2908 values (8, 10, 16) are supported. The total size is always given in two
2909 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2910 octal and hexadecimal if you're using @option{-o}.
2913 Print total size of common symbols in each file. When using Berkeley
2914 format these are included in the bss size.
2918 Show totals of all objects listed (Berkeley format listing mode only).
2920 @item --target=@var{bfdname}
2921 @cindex object code format
2922 Specify that the object-code format for @var{objfile} is
2923 @var{bfdname}. This option may not be necessary; @command{size} can
2924 automatically recognize many formats.
2925 @xref{Target Selection}, for more information.
2929 Display the version number of @command{size}.
2935 @c man begin SEEALSO size
2936 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2943 @cindex listings strings
2944 @cindex printing strings
2945 @cindex strings, printing
2947 @c man title strings print the strings of printable characters in files.
2950 @c man begin SYNOPSIS strings
2951 strings [@option{-afovV}] [@option{-}@var{min-len}]
2952 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2953 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2954 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2955 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2956 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2957 [@option{-w}] [@option{--include-all-whitespace}]
2958 [@option{-s}] [@option{--output-separator}@var{sep_string}]
2959 [@option{--help}] [@option{--version}] @var{file}@dots{}
2963 @c man begin DESCRIPTION strings
2965 For each @var{file} given, @sc{gnu} @command{strings} prints the
2966 printable character sequences that are at least 4 characters long (or
2967 the number given with the options below) and are followed by an
2968 unprintable character.
2970 Depending upon how the strings program was configured it will default
2971 to either displaying all the printable sequences that it can find in
2972 each file, or only those sequences that are in loadable, initialized
2973 data sections. If the file type in unrecognizable, or if strings is
2974 reading from stdin then it will always display all of the printable
2975 sequences that it can find.
2977 For backwards compatibility any file that occurs after a command line
2978 option of just @option{-} will also be scanned in full, regardless of
2979 the presence of any @option{-d} option.
2981 @command{strings} is mainly useful for determining the contents of
2986 @c man begin OPTIONS strings
2992 Scan the whole file, regardless of what sections it contains or
2993 whether those sections are loaded or initialized. Normally this is
2994 the default behaviour, but strings can be configured so that the
2995 @option{-d} is the default instead.
2997 The @option{-} option is position dependent and forces strings to
2998 perform full scans of any file that is mentioned after the @option{-}
2999 on the command line, even if the @option{-d} option has been
3004 Only print strings from initialized, loaded data sections in the
3005 file. This may reduce the amount of garbage in the output, but it
3006 also exposes the strings program to any security flaws that may be
3007 present in the BFD library used to scan and load sections. Strings
3008 can be configured so that this option is the default behaviour. In
3009 such cases the @option{-a} option can be used to avoid using the BFD
3010 library and instead just print all of the strings found in the file.
3013 @itemx --print-file-name
3014 Print the name of the file before each string.
3017 Print a summary of the program usage on the standard output and exit.
3019 @item -@var{min-len}
3020 @itemx -n @var{min-len}
3021 @itemx --bytes=@var{min-len}
3022 Print sequences of characters that are at least @var{min-len} characters
3023 long, instead of the default 4.
3026 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
3027 act like @samp{-t d} instead. Since we can not be compatible with both
3028 ways, we simply chose one.
3030 @item -t @var{radix}
3031 @itemx --radix=@var{radix}
3032 Print the offset within the file before each string. The single
3033 character argument specifies the radix of the offset---@samp{o} for
3034 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
3036 @item -e @var{encoding}
3037 @itemx --encoding=@var{encoding}
3038 Select the character encoding of the strings that are to be found.
3039 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
3040 characters (ASCII, ISO 8859, etc., default), @samp{S} =
3041 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
3042 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
3043 littleendian. Useful for finding wide character strings. (@samp{l}
3044 and @samp{b} apply to, for example, Unicode UTF-16/UCS-2 encodings).
3046 @item -T @var{bfdname}
3047 @itemx --target=@var{bfdname}
3048 @cindex object code format
3049 Specify an object code format other than your system's default format.
3050 @xref{Target Selection}, for more information.
3055 Print the program version number on the standard output and exit.
3058 @itemx --include-all-whitespace
3059 By default tab and space characters are included in the strings that
3060 are displayed, but other whitespace characters, such a newlines and
3061 carriage returns, are not. The @option{-w} option changes this so
3062 that all whitespace characters are considered to be part of a string.
3065 @itemx --output-separator
3066 By default, output strings are delimited by a new-line. This option
3067 allows you to supply any string to be used as the output record
3068 separator. Useful with --include-all-whitespace where strings
3069 may contain new-lines internally.
3075 @c man begin SEEALSO strings
3076 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
3077 and the Info entries for @file{binutils}.
3085 @cindex removing symbols
3086 @cindex discarding symbols
3087 @cindex symbols, discarding
3089 @c man title strip Discard symbols from object files.
3092 @c man begin SYNOPSIS strip
3093 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
3094 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
3095 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
3096 [@option{-s}|@option{--strip-all}]
3097 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
3098 [@option{--strip-dwo}]
3099 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
3100 [@option{-M}|@option{--merge-notes}][@option{--no-merge-notes}]
3101 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
3102 [@option{-w}|@option{--wildcard}]
3103 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
3104 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
3105 [@option{--remove-relocations=}@var{sectionpattern}]
3106 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
3107 [@option{-D}|@option{--enable-deterministic-archives}]
3108 [@option{-U}|@option{--disable-deterministic-archives}]
3109 [@option{--keep-file-symbols}]
3110 [@option{--only-keep-debug}]
3111 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
3112 [@option{--help}] [@option{--info}]
3113 @var{objfile}@dots{}
3117 @c man begin DESCRIPTION strip
3119 @sc{gnu} @command{strip} discards all symbols from object files
3120 @var{objfile}. The list of object files may include archives.
3121 At least one object file must be given.
3123 @command{strip} modifies the files named in its argument,
3124 rather than writing modified copies under different names.
3128 @c man begin OPTIONS strip
3131 @item -F @var{bfdname}
3132 @itemx --target=@var{bfdname}
3133 Treat the original @var{objfile} as a file with the object
3134 code format @var{bfdname}, and rewrite it in the same format.
3135 @xref{Target Selection}, for more information.
3138 Show a summary of the options to @command{strip} and exit.
3141 Display a list showing all architectures and object formats available.
3143 @item -I @var{bfdname}
3144 @itemx --input-target=@var{bfdname}
3145 Treat the original @var{objfile} as a file with the object
3146 code format @var{bfdname}.
3147 @xref{Target Selection}, for more information.
3149 @item -O @var{bfdname}
3150 @itemx --output-target=@var{bfdname}
3151 Replace @var{objfile} with a file in the output format @var{bfdname}.
3152 @xref{Target Selection}, for more information.
3154 @item -R @var{sectionname}
3155 @itemx --remove-section=@var{sectionname}
3156 Remove any section named @var{sectionname} from the output file, in
3157 addition to whatever sections would otherwise be removed. This
3158 option may be given more than once. Note that using this option
3159 inappropriately may make the output file unusable. The wildcard
3160 character @samp{*} may be given at the end of @var{sectionname}. If
3161 so, then any section starting with @var{sectionname} will be removed.
3163 If the first character of @var{sectionpattern} is the exclamation
3164 point (!) then matching sections will not be removed even if an
3165 earlier use of @option{--remove-section} on the same command line
3166 would otherwise remove it. For example:
3169 --remove-section=.text.* --remove-section=!.text.foo
3172 will remove all sections matching the pattern '.text.*', but will not
3173 remove the section '.text.foo'.
3175 @item --remove-relocations=@var{sectionpattern}
3176 Remove relocations from the output file for any section matching
3177 @var{sectionpattern}. This option may be given more than once. Note
3178 that using this option inappropriately may make the output file
3179 unusable. Wildcard characters are accepted in @var{sectionpattern}.
3183 --remove-relocations=.text.*
3186 will remove the relocations for all sections matching the patter
3189 If the first character of @var{sectionpattern} is the exclamation
3190 point (!) then matching sections will not have their relocation
3191 removed even if an earlier use of @option{--remove-relocations} on the
3192 same command line would otherwise cause the relocations to be removed.
3196 --remove-relocations=.text.* --remove-relocations=!.text.foo
3199 will remove all relocations for sections matching the pattern
3200 '.text.*', but will not remove relocations for the section
3210 @itemx --strip-debug
3211 Remove debugging symbols only.
3214 Remove the contents of all DWARF .dwo sections, leaving the
3215 remaining debugging sections and all symbols intact.
3216 See the description of this option in the @command{objcopy} section
3217 for more information.
3219 @item --strip-unneeded
3220 Remove all symbols that are not needed for relocation processing.
3222 @item -K @var{symbolname}
3223 @itemx --keep-symbol=@var{symbolname}
3224 When stripping symbols, keep symbol @var{symbolname} even if it would
3225 normally be stripped. This option may be given more than once.
3228 @itemx --merge-notes
3229 @itemx --no-merge-notes
3230 For ELF files, attempt (or do not attempt) to reduce the size of any
3231 SHT_NOTE type sections by removing duplicate notes. The default is to
3232 attempt this reduction.
3234 @item -N @var{symbolname}
3235 @itemx --strip-symbol=@var{symbolname}
3236 Remove symbol @var{symbolname} from the source file. This option may be
3237 given more than once, and may be combined with strip options other than
3241 Put the stripped output in @var{file}, rather than replacing the
3242 existing file. When this argument is used, only one @var{objfile}
3243 argument may be specified.
3246 @itemx --preserve-dates
3247 Preserve the access and modification dates of the file.
3250 @itemx --enable-deterministic-archives
3251 @cindex deterministic archives
3252 @kindex --enable-deterministic-archives
3253 Operate in @emph{deterministic} mode. When copying archive members
3254 and writing the archive index, use zero for UIDs, GIDs, timestamps,
3255 and use consistent file modes for all files.
3257 If @file{binutils} was configured with
3258 @option{--enable-deterministic-archives}, then this mode is on by default.
3259 It can be disabled with the @samp{-U} option, below.
3262 @itemx --disable-deterministic-archives
3263 @cindex deterministic archives
3264 @kindex --enable-deterministic-archives
3265 Do @emph{not} operate in @emph{deterministic} mode. This is the
3266 inverse of the @option{-D} option, above: when copying archive members
3267 and writing the archive index, use their actual UID, GID, timestamp,
3268 and file mode values.
3270 This is the default unless @file{binutils} was configured with
3271 @option{--enable-deterministic-archives}.
3275 Permit regular expressions in @var{symbolname}s used in other command
3276 line options. The question mark (?), asterisk (*), backslash (\) and
3277 square brackets ([]) operators can be used anywhere in the symbol
3278 name. If the first character of the symbol name is the exclamation
3279 point (!) then the sense of the switch is reversed for that symbol.
3286 would cause strip to only keep symbols that start with the letters
3287 ``fo'', but to discard the symbol ``foo''.
3290 @itemx --discard-all
3291 Remove non-global symbols.
3294 @itemx --discard-locals
3295 Remove compiler-generated local symbols.
3296 (These usually start with @samp{L} or @samp{.}.)
3298 @item --keep-file-symbols
3299 When stripping a file, perhaps with @option{--strip-debug} or
3300 @option{--strip-unneeded}, retain any symbols specifying source file names,
3301 which would otherwise get stripped.
3303 @item --only-keep-debug
3304 Strip a file, emptying the contents of any sections that would not be
3305 stripped by @option{--strip-debug} and leaving the debugging sections
3306 intact. In ELF files, this preserves all the note sections in the
3309 Note - the section headers of the stripped sections are preserved,
3310 including their sizes, but the contents of the section are discarded.
3311 The section headers are preserved so that other tools can match up the
3312 debuginfo file with the real executable, even if that executable has
3313 been relocated to a different address space.
3315 The intention is that this option will be used in conjunction with
3316 @option{--add-gnu-debuglink} to create a two part executable. One a
3317 stripped binary which will occupy less space in RAM and in a
3318 distribution and the second a debugging information file which is only
3319 needed if debugging abilities are required. The suggested procedure
3320 to create these files is as follows:
3323 @item Link the executable as normal. Assuming that is is called
3325 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
3326 create a file containing the debugging info.
3327 @item Run @code{objcopy --strip-debug foo} to create a
3328 stripped executable.
3329 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
3330 to add a link to the debugging info into the stripped executable.
3333 Note---the choice of @code{.dbg} as an extension for the debug info
3334 file is arbitrary. Also the @code{--only-keep-debug} step is
3335 optional. You could instead do this:
3338 @item Link the executable as normal.
3339 @item Copy @code{foo} to @code{foo.full}
3340 @item Run @code{strip --strip-debug foo}
3341 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
3344 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
3345 full executable. It does not have to be a file created by the
3346 @option{--only-keep-debug} switch.
3348 Note---this switch is only intended for use on fully linked files. It
3349 does not make sense to use it on object files where the debugging
3350 information may be incomplete. Besides the gnu_debuglink feature
3351 currently only supports the presence of one filename containing
3352 debugging information, not multiple filenames on a one-per-object-file
3357 Show the version number for @command{strip}.
3361 Verbose output: list all object files modified. In the case of
3362 archives, @samp{strip -v} lists all members of the archive.
3368 @c man begin SEEALSO strip
3369 the Info entries for @file{binutils}.
3373 @node c++filt, addr2line, strip, Top
3377 @cindex demangling C++ symbols
3379 @c man title cxxfilt Demangle C++ and Java symbols.
3382 @c man begin SYNOPSIS cxxfilt
3383 c++filt [@option{-_}|@option{--strip-underscore}]
3384 [@option{-n}|@option{--no-strip-underscore}]
3385 [@option{-p}|@option{--no-params}]
3386 [@option{-t}|@option{--types}]
3387 [@option{-i}|@option{--no-verbose}]
3388 [@option{-s} @var{format}|@option{--format=}@var{format}]
3389 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
3393 @c man begin DESCRIPTION cxxfilt
3396 The C++ and Java languages provide function overloading, which means
3397 that you can write many functions with the same name, providing that
3398 each function takes parameters of different types. In order to be
3399 able to distinguish these similarly named functions C++ and Java
3400 encode them into a low-level assembler name which uniquely identifies
3401 each different version. This process is known as @dfn{mangling}. The
3403 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
3404 MS-DOS this program is named @command{CXXFILT}.}
3405 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
3406 names into user-level names so that they can be read.
3408 Every alphanumeric word (consisting of letters, digits, underscores,
3409 dollars, or periods) seen in the input is a potential mangled name.
3410 If the name decodes into a C++ name, the C++ name replaces the
3411 low-level name in the output, otherwise the original word is output.
3412 In this way you can pass an entire assembler source file, containing
3413 mangled names, through @command{c++filt} and see the same source file
3414 containing demangled names.
3416 You can also use @command{c++filt} to decipher individual symbols by
3417 passing them on the command line:
3420 c++filt @var{symbol}
3423 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
3424 names from the standard input instead. All the results are printed on
3425 the standard output. The difference between reading names from the
3426 command line versus reading names from the standard input is that
3427 command line arguments are expected to be just mangled names and no
3428 checking is performed to separate them from surrounding text. Thus
3435 will work and demangle the name to ``f()'' whereas:
3441 will not work. (Note the extra comma at the end of the mangled
3442 name which makes it invalid). This command however will work:
3445 echo _Z1fv, | c++filt -n
3448 and will display ``f(),'', i.e., the demangled name followed by a
3449 trailing comma. This behaviour is because when the names are read
3450 from the standard input it is expected that they might be part of an
3451 assembler source file where there might be extra, extraneous
3452 characters trailing after a mangled name. For example:
3455 .type _Z1fv, @@function
3460 @c man begin OPTIONS cxxfilt
3464 @itemx --strip-underscore
3465 On some systems, both the C and C++ compilers put an underscore in front
3466 of every name. For example, the C name @code{foo} gets the low-level
3467 name @code{_foo}. This option removes the initial underscore. Whether
3468 @command{c++filt} removes the underscore by default is target dependent.
3471 @itemx --no-strip-underscore
3472 Do not remove the initial underscore.
3476 When demangling the name of a function, do not display the types of
3477 the function's parameters.
3481 Attempt to demangle types as well as function names. This is disabled
3482 by default since mangled types are normally only used internally in
3483 the compiler, and they can be confused with non-mangled names. For example,
3484 a function called ``a'' treated as a mangled type name would be
3485 demangled to ``signed char''.
3489 Do not include implementation details (if any) in the demangled
3492 @item -s @var{format}
3493 @itemx --format=@var{format}
3494 @command{c++filt} can decode various methods of mangling, used by
3495 different compilers. The argument to this option selects which
3500 Automatic selection based on executable (the default method)
3502 the one used by the @sc{gnu} C++ compiler (g++)
3504 the one used by the Lucid compiler (lcc)
3506 the one specified by the C++ Annotated Reference Manual
3508 the one used by the HP compiler (aCC)
3510 the one used by the EDG compiler
3512 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
3514 the one used by the @sc{gnu} Java compiler (gcj)
3516 the one used by the @sc{gnu} Ada compiler (GNAT).
3520 Print a summary of the options to @command{c++filt} and exit.
3523 Print the version number of @command{c++filt} and exit.
3529 @c man begin SEEALSO cxxfilt
3530 the Info entries for @file{binutils}.
3535 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
3536 user interface are subject to change in future releases. In particular,
3537 a command-line option may be required in the future to decode a name
3538 passed as an argument on the command line; in other words,
3541 c++filt @var{symbol}
3545 may in a future release become
3548 c++filt @var{option} @var{symbol}
3556 @cindex address to file name and line number
3558 @c man title addr2line convert addresses into file names and line numbers.
3561 @c man begin SYNOPSIS addr2line
3562 addr2line [@option{-a}|@option{--addresses}]
3563 [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
3564 [@option{-C}|@option{--demangle}[=@var{style}]]
3565 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
3566 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
3567 [@option{-i}|@option{--inlines}]
3568 [@option{-p}|@option{--pretty-print}]
3569 [@option{-j}|@option{--section=}@var{name}]
3570 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
3575 @c man begin DESCRIPTION addr2line
3577 @command{addr2line} translates addresses into file names and line numbers.
3578 Given an address in an executable or an offset in a section of a relocatable
3579 object, it uses the debugging information to figure out which file name and
3580 line number are associated with it.
3582 The executable or relocatable object to use is specified with the @option{-e}
3583 option. The default is the file @file{a.out}. The section in the relocatable
3584 object to use is specified with the @option{-j} option.
3586 @command{addr2line} has two modes of operation.
3588 In the first, hexadecimal addresses are specified on the command line,
3589 and @command{addr2line} displays the file name and line number for each
3592 In the second, @command{addr2line} reads hexadecimal addresses from
3593 standard input, and prints the file name and line number for each
3594 address on standard output. In this mode, @command{addr2line} may be used
3595 in a pipe to convert dynamically chosen addresses.
3597 The format of the output is @samp{FILENAME:LINENO}. By default
3598 each input address generates one line of output.
3600 Two options can generate additional lines before each
3601 @samp{FILENAME:LINENO} line (in that order).
3603 If the @option{-a} option is used then a line with the input address
3606 If the @option{-f} option is used, then a line with the
3607 @samp{FUNCTIONNAME} is displayed. This is the name of the function
3608 containing the address.
3610 One option can generate additional lines after the
3611 @samp{FILENAME:LINENO} line.
3613 If the @option{-i} option is used and the code at the given address is
3614 present there because of inlining by the compiler then additional
3615 lines are displayed afterwards. One or two extra lines (if the
3616 @option{-f} option is used) are displayed for each inlined function.
3618 Alternatively if the @option{-p} option is used then each input
3619 address generates a single, long, output line containing the address,
3620 the function name, the file name and the line number. If the
3621 @option{-i} option has also been used then any inlined functions will
3622 be displayed in the same manner, but on separate lines, and prefixed
3623 by the text @samp{(inlined by)}.
3625 If the file name or function name can not be determined,
3626 @command{addr2line} will print two question marks in their place. If the
3627 line number can not be determined, @command{addr2line} will print 0.
3631 @c man begin OPTIONS addr2line
3633 The long and short forms of options, shown here as alternatives, are
3639 Display the address before the function name, file and line number
3640 information. The address is printed with a @samp{0x} prefix to easily
3643 @item -b @var{bfdname}
3644 @itemx --target=@var{bfdname}
3645 @cindex object code format
3646 Specify that the object-code format for the object files is
3650 @itemx --demangle[=@var{style}]
3651 @cindex demangling in objdump
3652 Decode (@dfn{demangle}) low-level symbol names into user-level names.
3653 Besides removing any initial underscore prepended by the system, this
3654 makes C++ function names readable. Different compilers have different
3655 mangling styles. The optional demangling style argument can be used to
3656 choose an appropriate demangling style for your compiler. @xref{c++filt},
3657 for more information on demangling.
3659 @item -e @var{filename}
3660 @itemx --exe=@var{filename}
3661 Specify the name of the executable for which addresses should be
3662 translated. The default file is @file{a.out}.
3666 Display function names as well as file and line number information.
3670 Display only the base of each file name.
3674 If the address belongs to a function that was inlined, the source
3675 information for all enclosing scopes back to the first non-inlined
3676 function will also be printed. For example, if @code{main} inlines
3677 @code{callee1} which inlines @code{callee2}, and address is from
3678 @code{callee2}, the source information for @code{callee1} and @code{main}
3679 will also be printed.
3683 Read offsets relative to the specified section instead of absolute addresses.
3686 @itemx --pretty-print
3687 Make the output more human friendly: each location are printed on one line.
3688 If option @option{-i} is specified, lines for all enclosing scopes are
3689 prefixed with @samp{(inlined by)}.
3695 @c man begin SEEALSO addr2line
3696 Info entries for @file{binutils}.
3703 @command{nlmconv} converts a relocatable object file into a NetWare
3707 @command{nlmconv} currently works with @samp{i386} object
3708 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
3709 object files in @sc{elf}, or @code{a.out} format@footnote{
3710 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
3711 format in the Binary File Descriptor library. It has only been tested
3712 with the above formats.}.
3716 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
3717 utilities, since it is only useful for NLM targets.
3720 @c man title nlmconv converts object code into an NLM.
3723 @c man begin SYNOPSIS nlmconv
3724 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
3725 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
3726 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
3727 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
3728 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3729 @var{infile} @var{outfile}
3733 @c man begin DESCRIPTION nlmconv
3735 @command{nlmconv} converts the relocatable @samp{i386} object file
3736 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
3737 reading @var{headerfile} for NLM header information. For instructions
3738 on writing the NLM command file language used in header files, see the
3739 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
3740 Development and Tools Overview}, which is part of the NLM Software
3741 Developer's Kit (``NLM SDK''), available from Novell, Inc.
3742 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
3745 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
3748 @command{nlmconv} can perform a link step. In other words, you can list
3749 more than one object file for input if you list them in the definitions
3750 file (rather than simply specifying one input file on the command line).
3751 In this case, @command{nlmconv} calls the linker for you.
3755 @c man begin OPTIONS nlmconv
3758 @item -I @var{bfdname}
3759 @itemx --input-target=@var{bfdname}
3760 Object format of the input file. @command{nlmconv} can usually determine
3761 the format of a given file (so no default is necessary).
3762 @xref{Target Selection}, for more information.
3764 @item -O @var{bfdname}
3765 @itemx --output-target=@var{bfdname}
3766 Object format of the output file. @command{nlmconv} infers the output
3767 format based on the input format, e.g. for a @samp{i386} input file the
3768 output format is @samp{nlm32-i386}.
3769 @xref{Target Selection}, for more information.
3771 @item -T @var{headerfile}
3772 @itemx --header-file=@var{headerfile}
3773 Reads @var{headerfile} for NLM header information. For instructions on
3774 writing the NLM command file language used in header files, see@ see the
3775 @samp{linkers} section, of the @cite{NLM Development and Tools
3776 Overview}, which is part of the NLM Software Developer's Kit, available
3781 Displays (on standard error) the linker command line used by @command{nlmconv}.
3783 @item -l @var{linker}
3784 @itemx --linker=@var{linker}
3785 Use @var{linker} for any linking. @var{linker} can be an absolute or a
3790 Prints a usage summary.
3794 Prints the version number for @command{nlmconv}.
3800 @c man begin SEEALSO nlmconv
3801 the Info entries for @file{binutils}.
3808 @command{windmc} may be used to generator Windows message resources.
3811 @emph{Warning:} @command{windmc} is not always built as part of the binary
3812 utilities, since it is only useful for Windows targets.
3815 @c man title windmc generates Windows message resources.
3818 @c man begin SYNOPSIS windmc
3819 windmc [options] input-file
3823 @c man begin DESCRIPTION windmc
3825 @command{windmc} reads message definitions from an input file (.mc) and
3826 translate them into a set of output files. The output files may be of
3831 A C header file containing the message definitions.
3834 A resource file compilable by the @command{windres} tool.
3837 One or more binary files containing the resource data for a specific
3841 A C include file that maps message id's to their symbolic name.
3844 The exact description of these different formats is available in
3845 documentation from Microsoft.
3847 When @command{windmc} converts from the @code{mc} format to the @code{bin}
3848 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3849 Windows Message Compiler.
3853 @c man begin OPTIONS windmc
3858 Specifies that the input file specified is ASCII. This is the default
3863 Specifies that messages in the output @code{bin} files should be in ASCII
3868 Specifies that @code{bin} filenames should have to be prefixed by the
3869 basename of the source file.
3873 Sets the customer bit in all message id's.
3875 @item -C @var{codepage}
3876 @itemx --codepage_in @var{codepage}
3877 Sets the default codepage to be used to convert input file to UTF16. The
3878 default is ocdepage 1252.
3881 @itemx --decimal_values
3882 Outputs the constants in the header file in decimal. Default is using
3886 @itemx --extension @var{ext}
3887 The extension for the header file. The default is .h extension.
3889 @item -F @var{target}
3890 @itemx --target @var{target}
3891 Specify the BFD format to use for a bin file as output. This
3892 is a BFD target name; you can use the @option{--help} option to see a list
3893 of supported targets. Normally @command{windmc} will use the default
3894 format, which is the first one listed by the @option{--help} option.
3896 @ref{Target Selection}.
3900 @itemx --headerdir @var{path}
3901 The target directory of the generated header file. The default is the
3906 Displays a list of command line options and then exits.
3908 @item -m @var{characters}
3909 @itemx --maxlength @var{characters}
3910 Instructs @command{windmc} to generate a warning if the length
3911 of any message exceeds the number specified.
3914 @itemx --nullterminate
3915 Terminate message text in @code{bin} files by zero. By default they are
3916 terminated by CR/LF.
3919 @itemx --hresult_use
3920 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3921 file, using HRESULT definitions. Status codes are used if the flag is not
3924 @item -O @var{codepage}
3925 @itemx --codepage_out @var{codepage}
3926 Sets the default codepage to be used to output text files. The default
3930 @itemx --rcdir @var{path}
3931 The target directory for the generated @code{rc} script and the generated
3932 @code{bin} files that the resource compiler script includes. The default
3933 is the current directory.
3937 Specifies that the input file is UTF16.
3940 @itemx --unicode_out
3941 Specifies that messages in the output @code{bin} file should be in UTF16
3942 format. This is the default behaviour.
3946 Enable verbose mode.
3950 Prints the version number for @command{windmc}.
3953 @itemx --xdgb @var{path}
3954 The path of the @code{dbg} C include file that maps message id's to the
3955 symbolic name. No such file is generated without specifying the switch.
3961 @c man begin SEEALSO windmc
3962 the Info entries for @file{binutils}.
3969 @command{windres} may be used to manipulate Windows resources.
3972 @emph{Warning:} @command{windres} is not always built as part of the binary
3973 utilities, since it is only useful for Windows targets.
3976 @c man title windres manipulate Windows resources.
3979 @c man begin SYNOPSIS windres
3980 windres [options] [input-file] [output-file]
3984 @c man begin DESCRIPTION windres
3986 @command{windres} reads resources from an input file and copies them into
3987 an output file. Either file may be in one of three formats:
3991 A text format read by the Resource Compiler.
3994 A binary format generated by the Resource Compiler.
3997 A COFF object or executable.
4000 The exact description of these different formats is available in
4001 documentation from Microsoft.
4003 When @command{windres} converts from the @code{rc} format to the @code{res}
4004 format, it is acting like the Windows Resource Compiler. When
4005 @command{windres} converts from the @code{res} format to the @code{coff}
4006 format, it is acting like the Windows @code{CVTRES} program.
4008 When @command{windres} generates an @code{rc} file, the output is similar
4009 but not identical to the format expected for the input. When an input
4010 @code{rc} file refers to an external filename, an output @code{rc} file
4011 will instead include the file contents.
4013 If the input or output format is not specified, @command{windres} will
4014 guess based on the file name, or, for the input file, the file contents.
4015 A file with an extension of @file{.rc} will be treated as an @code{rc}
4016 file, a file with an extension of @file{.res} will be treated as a
4017 @code{res} file, and a file with an extension of @file{.o} or
4018 @file{.exe} will be treated as a @code{coff} file.
4020 If no output file is specified, @command{windres} will print the resources
4021 in @code{rc} format to standard output.
4023 The normal use is for you to write an @code{rc} file, use @command{windres}
4024 to convert it to a COFF object file, and then link the COFF file into
4025 your application. This will make the resources described in the
4026 @code{rc} file available to Windows.
4030 @c man begin OPTIONS windres
4033 @item -i @var{filename}
4034 @itemx --input @var{filename}
4035 The name of the input file. If this option is not used, then
4036 @command{windres} will use the first non-option argument as the input file
4037 name. If there are no non-option arguments, then @command{windres} will
4038 read from standard input. @command{windres} can not read a COFF file from
4041 @item -o @var{filename}
4042 @itemx --output @var{filename}
4043 The name of the output file. If this option is not used, then
4044 @command{windres} will use the first non-option argument, after any used
4045 for the input file name, as the output file name. If there is no
4046 non-option argument, then @command{windres} will write to standard output.
4047 @command{windres} can not write a COFF file to standard output. Note,
4048 for compatibility with @command{rc} the option @option{-fo} is also
4049 accepted, but its use is not recommended.
4051 @item -J @var{format}
4052 @itemx --input-format @var{format}
4053 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
4054 @samp{coff}. If no input format is specified, @command{windres} will
4055 guess, as described above.
4057 @item -O @var{format}
4058 @itemx --output-format @var{format}
4059 The output format to generate. @var{format} may be @samp{res},
4060 @samp{rc}, or @samp{coff}. If no output format is specified,
4061 @command{windres} will guess, as described above.
4063 @item -F @var{target}
4064 @itemx --target @var{target}
4065 Specify the BFD format to use for a COFF file as input or output. This
4066 is a BFD target name; you can use the @option{--help} option to see a list
4067 of supported targets. Normally @command{windres} will use the default
4068 format, which is the first one listed by the @option{--help} option.
4070 @ref{Target Selection}.
4073 @item --preprocessor @var{program}
4074 When @command{windres} reads an @code{rc} file, it runs it through the C
4075 preprocessor first. This option may be used to specify the preprocessor
4076 to use, including any leading arguments. The default preprocessor
4077 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
4079 @item --preprocessor-arg @var{option}
4080 When @command{windres} reads an @code{rc} file, it runs it through
4081 the C preprocessor first. This option may be used to specify additional
4082 text to be passed to preprocessor on its command line.
4083 This option can be used multiple times to add multiple options to the
4084 preprocessor command line.
4086 @item -I @var{directory}
4087 @itemx --include-dir @var{directory}
4088 Specify an include directory to use when reading an @code{rc} file.
4089 @command{windres} will pass this to the preprocessor as an @option{-I}
4090 option. @command{windres} will also search this directory when looking for
4091 files named in the @code{rc} file. If the argument passed to this command
4092 matches any of the supported @var{formats} (as described in the @option{-J}
4093 option), it will issue a deprecation warning, and behave just like the
4094 @option{-J} option. New programs should not use this behaviour. If a
4095 directory happens to match a @var{format}, simple prefix it with @samp{./}
4096 to disable the backward compatibility.
4098 @item -D @var{target}
4099 @itemx --define @var{sym}[=@var{val}]
4100 Specify a @option{-D} option to pass to the preprocessor when reading an
4103 @item -U @var{target}
4104 @itemx --undefine @var{sym}
4105 Specify a @option{-U} option to pass to the preprocessor when reading an
4109 Ignored for compatibility with rc.
4112 Enable verbose mode. This tells you what the preprocessor is if you
4116 @item --codepage @var{val}
4117 Specify the default codepage to use when reading an @code{rc} file.
4118 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
4119 codepage code. The valid range is from zero up to 0xffff, but the
4120 validity of the codepage is host and configuration dependent.
4123 @item --language @var{val}
4124 Specify the default language to use when reading an @code{rc} file.
4125 @var{val} should be a hexadecimal language code. The low eight bits are
4126 the language, and the high eight bits are the sublanguage.
4128 @item --use-temp-file
4129 Use a temporary file to instead of using popen to read the output of
4130 the preprocessor. Use this option if the popen implementation is buggy
4131 on the host (eg., certain non-English language versions of Windows 95 and
4132 Windows 98 are known to have buggy popen where the output will instead
4135 @item --no-use-temp-file
4136 Use popen, not a temporary file, to read the output of the preprocessor.
4137 This is the default behaviour.
4141 Prints a usage summary.
4145 Prints the version number for @command{windres}.
4148 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
4149 this will turn on parser debugging.
4155 @c man begin SEEALSO windres
4156 the Info entries for @file{binutils}.
4165 @command{dlltool} is used to create the files needed to create dynamic
4166 link libraries (DLLs) on systems which understand PE format image
4167 files such as Windows. A DLL contains an export table which contains
4168 information that the runtime loader needs to resolve references from a
4169 referencing program.
4171 The export table is generated by this program by reading in a
4172 @file{.def} file or scanning the @file{.a} and @file{.o} files which
4173 will be in the DLL. A @file{.o} file can contain information in
4174 special @samp{.drectve} sections with export information.
4177 @emph{Note:} @command{dlltool} is not always built as part of the
4178 binary utilities, since it is only useful for those targets which
4182 @c man title dlltool Create files needed to build and use DLLs.
4185 @c man begin SYNOPSIS dlltool
4186 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
4187 [@option{-b}|@option{--base-file} @var{base-file-name}]
4188 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
4189 [@option{-z}|@option{--output-def} @var{def-file-name}]
4190 [@option{-l}|@option{--output-lib} @var{library-file-name}]
4191 [@option{-y}|@option{--output-delaylib} @var{library-file-name}]
4192 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
4193 [@option{--exclude-symbols} @var{list}]
4194 [@option{--no-default-excludes}]
4195 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
4196 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
4197 [@option{-a}|@option{--add-indirect}]
4198 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
4199 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
4200 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
4201 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}]
4202 [@option{--use-nul-prefixed-import-tables}]
4203 [@option{-I}|@option{--identify} @var{library-file-name}] [@option{--identify-strict}]
4204 [@option{-i}|@option{--interwork}]
4205 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
4206 [@option{-v}|@option{--verbose}]
4207 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
4208 [@option{--no-leading-underscore}] [@option{--leading-underscore}]
4209 [object-file @dots{}]
4213 @c man begin DESCRIPTION dlltool
4215 @command{dlltool} reads its inputs, which can come from the @option{-d} and
4216 @option{-b} options as well as object files specified on the command
4217 line. It then processes these inputs and if the @option{-e} option has
4218 been specified it creates a exports file. If the @option{-l} option
4219 has been specified it creates a library file and if the @option{-z} option
4220 has been specified it creates a def file. Any or all of the @option{-e},
4221 @option{-l} and @option{-z} options can be present in one invocation of
4224 When creating a DLL, along with the source for the DLL, it is necessary
4225 to have three other files. @command{dlltool} can help with the creation of
4228 The first file is a @file{.def} file which specifies which functions are
4229 exported from the DLL, which functions the DLL imports, and so on. This
4230 is a text file and can be created by hand, or @command{dlltool} can be used
4231 to create it using the @option{-z} option. In this case @command{dlltool}
4232 will scan the object files specified on its command line looking for
4233 those functions which have been specially marked as being exported and
4234 put entries for them in the @file{.def} file it creates.
4236 In order to mark a function as being exported from a DLL, it needs to
4237 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
4238 section of the object file. This can be done in C by using the
4242 asm (".section .drectve");
4243 asm (".ascii \"-export:my_func\"");
4245 int my_func (void) @{ @dots{} @}
4248 The second file needed for DLL creation is an exports file. This file
4249 is linked with the object files that make up the body of the DLL and it
4250 handles the interface between the DLL and the outside world. This is a
4251 binary file and it can be created by giving the @option{-e} option to
4252 @command{dlltool} when it is creating or reading in a @file{.def} file.
4254 The third file needed for DLL creation is the library file that programs
4255 will link with in order to access the functions in the DLL (an `import
4256 library'). This file can be created by giving the @option{-l} option to
4257 dlltool when it is creating or reading in a @file{.def} file.
4259 If the @option{-y} option is specified, dlltool generates a delay-import
4260 library that can be used instead of the normal import library to allow
4261 a program to link to the dll only as soon as an imported function is
4262 called for the first time. The resulting executable will need to be
4263 linked to the static delayimp library containing __delayLoadHelper2(),
4264 which in turn will import LoadLibraryA and GetProcAddress from kernel32.
4266 @command{dlltool} builds the library file by hand, but it builds the
4267 exports file by creating temporary files containing assembler statements
4268 and then assembling these. The @option{-S} command line option can be
4269 used to specify the path to the assembler that dlltool will use,
4270 and the @option{-f} option can be used to pass specific flags to that
4271 assembler. The @option{-n} can be used to prevent dlltool from deleting
4272 these temporary assembler files when it is done, and if @option{-n} is
4273 specified twice then this will prevent dlltool from deleting the
4274 temporary object files it used to build the library.
4276 Here is an example of creating a DLL from a source file @samp{dll.c} and
4277 also creating a program (from an object file called @samp{program.o})
4282 dlltool -e exports.o -l dll.lib dll.o
4283 gcc dll.o exports.o -o dll.dll
4284 gcc program.o dll.lib -o program
4288 @command{dlltool} may also be used to query an existing import library
4289 to determine the name of the DLL to which it is associated. See the
4290 description of the @option{-I} or @option{--identify} option.
4294 @c man begin OPTIONS dlltool
4296 The command line options have the following meanings:
4300 @item -d @var{filename}
4301 @itemx --input-def @var{filename}
4302 @cindex input .def file
4303 Specifies the name of a @file{.def} file to be read in and processed.
4305 @item -b @var{filename}
4306 @itemx --base-file @var{filename}
4308 Specifies the name of a base file to be read in and processed. The
4309 contents of this file will be added to the relocation section in the
4310 exports file generated by dlltool.
4312 @item -e @var{filename}
4313 @itemx --output-exp @var{filename}
4314 Specifies the name of the export file to be created by dlltool.
4316 @item -z @var{filename}
4317 @itemx --output-def @var{filename}
4318 Specifies the name of the @file{.def} file to be created by dlltool.
4320 @item -l @var{filename}
4321 @itemx --output-lib @var{filename}
4322 Specifies the name of the library file to be created by dlltool.
4324 @item -y @var{filename}
4325 @itemx --output-delaylib @var{filename}
4326 Specifies the name of the delay-import library file to be created by dlltool.
4328 @item --export-all-symbols
4329 Treat all global and weak defined symbols found in the input object
4330 files as symbols to be exported. There is a small list of symbols which
4331 are not exported by default; see the @option{--no-default-excludes}
4332 option. You may add to the list of symbols to not export by using the
4333 @option{--exclude-symbols} option.
4335 @item --no-export-all-symbols
4336 Only export symbols explicitly listed in an input @file{.def} file or in
4337 @samp{.drectve} sections in the input object files. This is the default
4338 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
4339 attributes in the source code.
4341 @item --exclude-symbols @var{list}
4342 Do not export the symbols in @var{list}. This is a list of symbol names
4343 separated by comma or colon characters. The symbol names should not
4344 contain a leading underscore. This is only meaningful when
4345 @option{--export-all-symbols} is used.
4347 @item --no-default-excludes
4348 When @option{--export-all-symbols} is used, it will by default avoid
4349 exporting certain special symbols. The current list of symbols to avoid
4350 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
4351 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
4352 to go ahead and export these special symbols. This is only meaningful
4353 when @option{--export-all-symbols} is used.
4356 @itemx --as @var{path}
4357 Specifies the path, including the filename, of the assembler to be used
4358 to create the exports file.
4360 @item -f @var{options}
4361 @itemx --as-flags @var{options}
4362 Specifies any specific command line options to be passed to the
4363 assembler when building the exports file. This option will work even if
4364 the @option{-S} option is not used. This option only takes one argument,
4365 and if it occurs more than once on the command line, then later
4366 occurrences will override earlier occurrences. So if it is necessary to
4367 pass multiple options to the assembler they should be enclosed in
4371 @itemx --dll-name @var{name}
4372 Specifies the name to be stored in the @file{.def} file as the name of
4373 the DLL when the @option{-e} option is used. If this option is not
4374 present, then the filename given to the @option{-e} option will be
4375 used as the name of the DLL.
4377 @item -m @var{machine}
4378 @itemx -machine @var{machine}
4379 Specifies the type of machine for which the library file should be
4380 built. @command{dlltool} has a built in default type, depending upon how
4381 it was created, but this option can be used to override that. This is
4382 normally only useful when creating DLLs for an ARM processor, when the
4383 contents of the DLL are actually encode using Thumb instructions.
4386 @itemx --add-indirect
4387 Specifies that when @command{dlltool} is creating the exports file it
4388 should add a section which allows the exported functions to be
4389 referenced without using the import library. Whatever the hell that
4393 @itemx --add-underscore
4394 Specifies that when @command{dlltool} is creating the exports file it
4395 should prepend an underscore to the names of @emph{all} exported symbols.
4397 @item --no-leading-underscore
4398 @item --leading-underscore
4399 Specifies whether standard symbol should be forced to be prefixed, or
4402 @item --add-stdcall-underscore
4403 Specifies that when @command{dlltool} is creating the exports file it
4404 should prepend an underscore to the names of exported @emph{stdcall}
4405 functions. Variable names and non-stdcall function names are not modified.
4406 This option is useful when creating GNU-compatible import libs for third
4407 party DLLs that were built with MS-Windows tools.
4411 Specifies that @samp{@@<number>} suffixes should be omitted from the names
4412 of stdcall functions that will be imported from the DLL. This is
4413 useful when creating an import library for a DLL which exports stdcall
4414 functions but without the usual @samp{@@<number>} symbol name suffix.
4416 This does not change the naming of symbols provided by the import library
4417 to programs linked against it, but only the entries in the import table
4418 (ie the .idata section).
4421 @itemx --add-stdcall-alias
4422 Specifies that when @command{dlltool} is creating the exports file it
4423 should add aliases for stdcall symbols without @samp{@@ <number>}
4424 in addition to the symbols with @samp{@@ <number>}.
4427 @itemx --ext-prefix-alias @var{prefix}
4428 Causes @command{dlltool} to create external aliases for all DLL
4429 imports with the specified prefix. The aliases are created for both
4430 external and import symbols with no leading underscore.
4434 Specifies that when @command{dlltool} is creating the exports and library
4435 files it should omit the @code{.idata4} section. This is for compatibility
4436 with certain operating systems.
4438 @item --use-nul-prefixed-import-tables
4439 Specifies that when @command{dlltool} is creating the exports and library
4440 files it should prefix the @code{.idata4} and @code{.idata5} by zero an
4441 element. This emulates old gnu import library generation of
4442 @code{dlltool}. By default this option is turned off.
4446 Specifies that when @command{dlltool} is creating the exports and library
4447 files it should omit the @code{.idata5} section. This is for compatibility
4448 with certain operating systems.
4450 @item -I @var{filename}
4451 @itemx --identify @var{filename}
4452 Specifies that @command{dlltool} should inspect the import library
4453 indicated by @var{filename} and report, on @code{stdout}, the name(s)
4454 of the associated DLL(s). This can be performed in addition to any
4455 other operations indicated by the other options and arguments.
4456 @command{dlltool} fails if the import library does not exist or is not
4457 actually an import library. See also @option{--identify-strict}.
4459 @item --identify-strict
4460 Modifies the behavior of the @option{--identify} option, such
4461 that an error is reported if @var{filename} is associated with
4466 Specifies that @command{dlltool} should mark the objects in the library
4467 file and exports file that it produces as supporting interworking
4468 between ARM and Thumb code.
4472 Makes @command{dlltool} preserve the temporary assembler files it used to
4473 create the exports file. If this option is repeated then dlltool will
4474 also preserve the temporary object files it uses to create the library
4477 @item -t @var{prefix}
4478 @itemx --temp-prefix @var{prefix}
4479 Makes @command{dlltool} use @var{prefix} when constructing the names of
4480 temporary assembler and object files. By default, the temp file prefix
4481 is generated from the pid.
4485 Make dlltool describe what it is doing.
4489 Displays a list of command line options and then exits.
4493 Displays dlltool's version number and then exits.
4500 * def file format:: The format of the dlltool @file{.def} file
4503 @node def file format
4504 @section The format of the @command{dlltool} @file{.def} file
4506 A @file{.def} file contains any number of the following commands:
4510 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
4511 The result is going to be named @var{name}@code{.exe}.
4513 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
4514 The result is going to be named @var{name}@code{.dll}.
4515 Note: If you want to use LIBRARY as name then you need to quote. Otherwise
4516 this will fail due a necessary hack for libtool (see PR binutils/13710 for more
4519 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) ) [ == } @var{its_name} @code{]}
4520 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
4521 Declares @var{name1} as an exported symbol from the DLL, with optional
4522 ordinal number @var{integer}, or declares @var{name1} as an alias
4523 (forward) of the function @var{external-name} in the DLL.
4524 If @var{its_name} is specified, this name is used as string in export table.
4526 Note: The @code{EXPORTS} has to be the last command in .def file, as keywords
4527 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4528 If you want to use LIBRARY as name then you need to quote it.
4530 @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{]} *}
4531 Declares that @var{external-name} or the exported function whose
4532 ordinal number is @var{integer} is to be imported from the file
4533 @var{module-name}. If @var{internal-name} is specified then this is
4534 the name that the imported function will be referred to in the body of
4536 If @var{its_name} is specified, this name is used as string in import table.
4537 Note: The @code{IMPORTS} has to be the last command in .def file, as keywords
4538 are treated - beside @code{LIBRARY} - as simple name-identifiers.
4539 If you want to use LIBRARY as name then you need to quote it.
4541 @item @code{DESCRIPTION} @var{string}
4542 Puts @var{string} into the output @file{.exp} file in the
4543 @code{.rdata} section.
4545 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4546 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
4547 Generates @code{--stack} or @code{--heap}
4548 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
4549 section. The linker will see this and act upon it.
4551 @item @code{CODE} @var{attr} @code{+}
4552 @item @code{DATA} @var{attr} @code{+}
4553 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
4554 Generates @code{--attr} @var{section-name} @var{attr} in the output
4555 @code{.drectve} section, where @var{attr} is one of @code{READ},
4556 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
4557 this and act upon it.
4562 @c man begin SEEALSO dlltool
4563 The Info pages for @file{binutils}.
4570 @cindex ELF file information
4573 @c man title readelf Displays information about ELF files.
4576 @c man begin SYNOPSIS readelf
4577 readelf [@option{-a}|@option{--all}]
4578 [@option{-h}|@option{--file-header}]
4579 [@option{-l}|@option{--program-headers}|@option{--segments}]
4580 [@option{-S}|@option{--section-headers}|@option{--sections}]
4581 [@option{-g}|@option{--section-groups}]
4582 [@option{-t}|@option{--section-details}]
4583 [@option{-e}|@option{--headers}]
4584 [@option{-s}|@option{--syms}|@option{--symbols}]
4585 [@option{--dyn-syms}]
4586 [@option{-n}|@option{--notes}]
4587 [@option{-r}|@option{--relocs}]
4588 [@option{-u}|@option{--unwind}]
4589 [@option{-d}|@option{--dynamic}]
4590 [@option{-V}|@option{--version-info}]
4591 [@option{-A}|@option{--arch-specific}]
4592 [@option{-D}|@option{--use-dynamic}]
4593 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
4594 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
4595 [@option{-R} <number or name>|@option{--relocated-dump=}<number or name>]
4596 [@option{-z}|@option{--decompress}]
4597 [@option{-c}|@option{--archive-index}]
4598 [@option{-w[lLiaprmfFsoRtUuTgAckK]}|
4599 @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]]
4600 [@option{--dwarf-depth=@var{n}}]
4601 [@option{--dwarf-start=@var{n}}]
4602 [@option{-I}|@option{--histogram}]
4603 [@option{-v}|@option{--version}]
4604 [@option{-W}|@option{--wide}]
4605 [@option{-H}|@option{--help}]
4606 @var{elffile}@dots{}
4610 @c man begin DESCRIPTION readelf
4612 @command{readelf} displays information about one or more ELF format object
4613 files. The options control what particular information to display.
4615 @var{elffile}@dots{} are the object files to be examined. 32-bit and
4616 64-bit ELF files are supported, as are archives containing ELF files.
4618 This program performs a similar function to @command{objdump} but it
4619 goes into more detail and it exists independently of the @sc{bfd}
4620 library, so if there is a bug in @sc{bfd} then readelf will not be
4625 @c man begin OPTIONS readelf
4627 The long and short forms of options, shown here as alternatives, are
4628 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
4634 Equivalent to specifying @option{--file-header},
4635 @option{--program-headers}, @option{--sections}, @option{--symbols},
4636 @option{--relocs}, @option{--dynamic}, @option{--notes},
4637 @option{--version-info}, @option{--arch-specific}, @option{--unwind},
4638 @option{--section-groups} and @option{--histogram}.
4640 Note - this option does not enable @option{--use-dynamic} itself, so
4641 if that option is not present on the command line then dynamic symbols
4642 and dynamic relocs will not be displayed.
4645 @itemx --file-header
4646 @cindex ELF file header information
4647 Displays the information contained in the ELF header at the start of the
4651 @itemx --program-headers
4653 @cindex ELF program header information
4654 @cindex ELF segment information
4655 Displays the information contained in the file's segment headers, if it
4660 @itemx --section-headers
4661 @cindex ELF section information
4662 Displays the information contained in the file's section headers, if it
4666 @itemx --section-groups
4667 @cindex ELF section group information
4668 Displays the information contained in the file's section groups, if it
4672 @itemx --section-details
4673 @cindex ELF section information
4674 Displays the detailed section information. Implies @option{-S}.
4679 @cindex ELF symbol table information
4680 Displays the entries in symbol table section of the file, if it has one.
4681 If a symbol has version information associated with it then this is
4682 displayed as well. The version string is displayed as a suffix to the
4683 symbol name, preceeded by an @@ character. For example
4684 @samp{foo@@VER_1}. If the version is the default version to be used
4685 when resolving unversioned references to the symbol then it is
4686 displayed as a suffix preceeded by two @@ characters. For example
4687 @samp{foo@@@@VER_2}.
4690 @cindex ELF dynamic symbol table information
4691 Displays the entries in dynamic symbol table section of the file, if it
4692 has one. The output format is the same as the format used by the
4693 @option{--syms} option.
4697 Display all the headers in the file. Equivalent to @option{-h -l -S}.
4702 Displays the contents of the NOTE segments and/or sections, if any.
4706 @cindex ELF reloc information
4707 Displays the contents of the file's relocation section, if it has one.
4711 @cindex unwind information
4712 Displays the contents of the file's unwind section, if it has one. Only
4713 the unwind sections for IA64 ELF files, as well as ARM unwind tables
4714 (@code{.ARM.exidx} / @code{.ARM.extab}) are currently supported.
4718 @cindex ELF dynamic section information
4719 Displays the contents of the file's dynamic section, if it has one.
4722 @itemx --version-info
4723 @cindex ELF version sections information
4724 Displays the contents of the version sections in the file, it they
4728 @itemx --arch-specific
4729 Displays architecture-specific information in the file, if there
4733 @itemx --use-dynamic
4734 When displaying symbols, this option makes @command{readelf} use the
4735 symbol hash tables in the file's dynamic section, rather than the
4736 symbol table sections.
4738 When displaying relocations, this option makes @command{readelf}
4739 display the dynamic relocations rather than the static relocations.
4741 @item -x <number or name>
4742 @itemx --hex-dump=<number or name>
4743 Displays the contents of the indicated section as a hexadecimal bytes.
4744 A number identifies a particular section by index in the section table;
4745 any other string identifies all sections with that name in the object file.
4747 @item -R <number or name>
4748 @itemx --relocated-dump=<number or name>
4749 Displays the contents of the indicated section as a hexadecimal
4750 bytes. A number identifies a particular section by index in the
4751 section table; any other string identifies all sections with that name
4752 in the object file. The contents of the section will be relocated
4753 before they are displayed.
4755 @item -p <number or name>
4756 @itemx --string-dump=<number or name>
4757 Displays the contents of the indicated section as printable strings.
4758 A number identifies a particular section by index in the section table;
4759 any other string identifies all sections with that name in the object file.
4763 Requests that the section(s) being dumped by @option{x}, @option{R} or
4764 @option{p} options are decompressed before being displayed. If the
4765 section(s) are not compressed then they are displayed as is.
4768 @itemx --archive-index
4769 @cindex Archive file symbol index information
4770 Displays the file symbol index information contained in the header part
4771 of binary archives. Performs the same function as the @option{t}
4772 command to @command{ar}, but without using the BFD library. @xref{ar}.
4774 @item -w[lLiaprmfFsoRtUuTgAckK]
4775 @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]
4776 @include debug.options.texi
4780 Display a histogram of bucket list lengths when displaying the contents
4781 of the symbol tables.
4785 Display the version number of readelf.
4789 Don't break output lines to fit into 80 columns. By default
4790 @command{readelf} breaks section header and segment listing lines for
4791 64-bit ELF files, so that they fit into 80 columns. This option causes
4792 @command{readelf} to print each section header resp. each segment one a
4793 single line, which is far more readable on terminals wider than 80 columns.
4797 Display the command line options understood by @command{readelf}.
4804 @c man begin SEEALSO readelf
4805 objdump(1), and the Info entries for @file{binutils}.
4812 @cindex Update ELF header
4815 @c man title elfedit Update the ELF header of ELF files.
4818 @c man begin SYNOPSIS elfedit
4819 elfedit [@option{--input-mach=}@var{machine}]
4820 [@option{--input-type=}@var{type}]
4821 [@option{--input-osabi=}@var{osabi}]
4822 @option{--output-mach=}@var{machine}
4823 @option{--output-type=}@var{type}
4824 @option{--output-osabi=}@var{osabi}
4825 [@option{-v}|@option{--version}]
4826 [@option{-h}|@option{--help}]
4827 @var{elffile}@dots{}
4831 @c man begin DESCRIPTION elfedit
4833 @command{elfedit} updates the ELF header of ELF files which have
4834 the matching ELF machine and file types. The options control how and
4835 which fields in the ELF header should be updated.
4837 @var{elffile}@dots{} are the ELF files to be updated. 32-bit and
4838 64-bit ELF files are supported, as are archives containing ELF files.
4841 @c man begin OPTIONS elfedit
4843 The long and short forms of options, shown here as alternatives, are
4844 equivalent. At least one of the @option{--output-mach},
4845 @option{--output-type} and @option{--output-osabi} options must be given.
4849 @item --input-mach=@var{machine}
4850 Set the matching input ELF machine type to @var{machine}. If
4851 @option{--input-mach} isn't specified, it will match any ELF
4854 The supported ELF machine types are, @var{i386}, @var{IAMCU}, @var{L1OM},
4855 @var{K1OM} and @var{x86-64}.
4857 @item --output-mach=@var{machine}
4858 Change the ELF machine type in the ELF header to @var{machine}. The
4859 supported ELF machine types are the same as @option{--input-mach}.
4861 @item --input-type=@var{type}
4862 Set the matching input ELF file type to @var{type}. If
4863 @option{--input-type} isn't specified, it will match any ELF file types.
4865 The supported ELF file types are, @var{rel}, @var{exec} and @var{dyn}.
4867 @item --output-type=@var{type}
4868 Change the ELF file type in the ELF header to @var{type}. The
4869 supported ELF types are the same as @option{--input-type}.
4871 @item --input-osabi=@var{osabi}
4872 Set the matching input ELF file OSABI to @var{osabi}. If
4873 @option{--input-osabi} isn't specified, it will match any ELF OSABIs.
4875 The supported ELF OSABIs are, @var{none}, @var{HPUX}, @var{NetBSD},
4876 @var{GNU}, @var{Linux} (alias for @var{GNU}),
4877 @var{Solaris}, @var{AIX}, @var{Irix},
4878 @var{FreeBSD}, @var{TRU64}, @var{Modesto}, @var{OpenBSD}, @var{OpenVMS},
4879 @var{NSK}, @var{AROS} and @var{FenixOS}.
4881 @item --output-osabi=@var{osabi}
4882 Change the ELF OSABI in the ELF header to @var{osabi}. The
4883 supported ELF OSABI are the same as @option{--input-osabi}.
4887 Display the version number of @command{elfedit}.
4891 Display the command line options understood by @command{elfedit}.
4898 @c man begin SEEALSO elfedit
4899 readelf(1), and the Info entries for @file{binutils}.
4903 @node Common Options
4904 @chapter Common Options
4906 The following command-line options are supported by all of the
4907 programs described in this manual.
4909 @c man begin OPTIONS
4911 @include at-file.texi
4915 Display the command-line options supported by the program.
4918 Display the version number of the program.
4920 @c man begin OPTIONS
4924 @node Selecting the Target System
4925 @chapter Selecting the Target System
4927 You can specify two aspects of the target system to the @sc{gnu}
4928 binary file utilities, each in several ways:
4938 In the following summaries, the lists of ways to specify values are in
4939 order of decreasing precedence. The ways listed first override those
4942 The commands to list valid values only list the values for which the
4943 programs you are running were configured. If they were configured with
4944 @option{--enable-targets=all}, the commands list most of the available
4945 values, but a few are left out; not all targets can be configured in at
4946 once because some of them can only be configured @dfn{native} (on hosts
4947 with the same type as the target system).
4950 * Target Selection::
4951 * Architecture Selection::
4954 @node Target Selection
4955 @section Target Selection
4957 A @dfn{target} is an object file format. A given target may be
4958 supported for multiple architectures (@pxref{Architecture Selection}).
4959 A target selection may also have variations for different operating
4960 systems or architectures.
4962 The command to list valid target values is @samp{objdump -i}
4963 (the first column of output contains the relevant information).
4965 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
4966 @samp{a.out-sunos-big}.
4968 You can also specify a target using a configuration triplet. This is
4969 the same sort of name that is passed to @file{configure} to specify a
4970 target. When you use a configuration triplet as an argument, it must be
4971 fully canonicalized. You can see the canonical version of a triplet by
4972 running the shell script @file{config.sub} which is included with the
4975 Some sample configuration triplets are: @samp{m68k-hp-bsd},
4976 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
4978 @subheading @command{objdump} Target
4984 command line option: @option{-b} or @option{--target}
4987 environment variable @code{GNUTARGET}
4990 deduced from the input file
4993 @subheading @command{objcopy} and @command{strip} Input Target
4999 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
5002 environment variable @code{GNUTARGET}
5005 deduced from the input file
5008 @subheading @command{objcopy} and @command{strip} Output Target
5014 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
5017 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
5020 environment variable @code{GNUTARGET}
5023 deduced from the input file
5026 @subheading @command{nm}, @command{size}, and @command{strings} Target
5032 command line option: @option{--target}
5035 environment variable @code{GNUTARGET}
5038 deduced from the input file
5041 @node Architecture Selection
5042 @section Architecture Selection
5044 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
5045 to run. Its name may contain a colon, separating the name of the
5046 processor family from the name of the particular @sc{cpu}.
5048 The command to list valid architecture values is @samp{objdump -i} (the
5049 second column contains the relevant information).
5051 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
5053 @subheading @command{objdump} Architecture
5059 command line option: @option{-m} or @option{--architecture}
5062 deduced from the input file
5065 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
5071 deduced from the input file
5074 @node Reporting Bugs
5075 @chapter Reporting Bugs
5077 @cindex reporting bugs
5079 Your bug reports play an essential role in making the binary utilities
5082 Reporting a bug may help you by bringing a solution to your problem, or
5083 it may not. But in any case the principal function of a bug report is
5084 to help the entire community by making the next version of the binary
5085 utilities work better. Bug reports are your contribution to their
5088 In order for a bug report to serve its purpose, you must include the
5089 information that enables us to fix the bug.
5092 * Bug Criteria:: Have you found a bug?
5093 * Bug Reporting:: How to report bugs
5097 @section Have You Found a Bug?
5098 @cindex bug criteria
5100 If you are not sure whether you have found a bug, here are some guidelines:
5103 @cindex fatal signal
5106 If a binary utility gets a fatal signal, for any input whatever, that is
5107 a bug. Reliable utilities never crash.
5109 @cindex error on valid input
5111 If a binary utility produces an error message for valid input, that is a
5115 If you are an experienced user of binary utilities, your suggestions for
5116 improvement are welcome in any case.
5120 @section How to Report Bugs
5122 @cindex bugs, reporting
5124 A number of companies and individuals offer support for @sc{gnu}
5125 products. If you obtained the binary utilities from a support
5126 organization, we recommend you contact that organization first.
5128 You can find contact information for many support companies and
5129 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
5133 In any event, we also recommend that you send bug reports for the binary
5134 utilities to @value{BUGURL}.
5137 The fundamental principle of reporting bugs usefully is this:
5138 @strong{report all the facts}. If you are not sure whether to state a
5139 fact or leave it out, state it!
5141 Often people omit facts because they think they know what causes the
5142 problem and assume that some details do not matter. Thus, you might
5143 assume that the name of a file you use in an example does not matter.
5144 Well, probably it does not, but one cannot be sure. Perhaps the bug is
5145 a stray memory reference which happens to fetch from the location where
5146 that pathname is stored in memory; perhaps, if the pathname were
5147 different, the contents of that location would fool the utility into
5148 doing the right thing despite the bug. Play it safe and give a
5149 specific, complete example. That is the easiest thing for you to do,
5150 and the most helpful.
5152 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
5153 it is new to us. Therefore, always write your bug reports on the assumption
5154 that the bug has not been reported previously.
5156 Sometimes people give a few sketchy facts and ask, ``Does this ring a
5157 bell?'' This cannot help us fix a bug, so it is basically useless. We
5158 respond by asking for enough details to enable us to investigate.
5159 You might as well expedite matters by sending them to begin with.
5161 To enable us to fix the bug, you should include all these things:
5165 The version of the utility. Each utility announces it if you start it
5166 with the @option{--version} argument.
5168 Without this, we will not know whether there is any point in looking for
5169 the bug in the current version of the binary utilities.
5172 Any patches you may have applied to the source, including any patches
5173 made to the @code{BFD} library.
5176 The type of machine you are using, and the operating system name and
5180 What compiler (and its version) was used to compile the utilities---e.g.
5184 The command arguments you gave the utility to observe the bug. To
5185 guarantee you will not omit something important, list them all. A copy
5186 of the Makefile (or the output from make) is sufficient.
5188 If we were to try to guess the arguments, we would probably guess wrong
5189 and then we might not encounter the bug.
5192 A complete input file, or set of input files, that will reproduce the
5193 bug. If the utility is reading an object file or files, then it is
5194 generally most helpful to send the actual object files.
5196 If the source files were produced exclusively using @sc{gnu} programs
5197 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
5198 may be OK to send the source files rather than the object files. In
5199 this case, be sure to say exactly what version of @command{gcc}, or
5200 whatever, was used to produce the object files. Also say how
5201 @command{gcc}, or whatever, was configured.
5204 A description of what behavior you observe that you believe is
5205 incorrect. For example, ``It gets a fatal signal.''
5207 Of course, if the bug is that the utility gets a fatal signal, then we
5208 will certainly notice it. But if the bug is incorrect output, we might
5209 not notice unless it is glaringly wrong. You might as well not give us
5210 a chance to make a mistake.
5212 Even if the problem you experience is a fatal signal, you should still
5213 say so explicitly. Suppose something strange is going on, such as your
5214 copy of the utility is out of sync, or you have encountered a bug in
5215 the C library on your system. (This has happened!) Your copy might
5216 crash and ours would not. If you told us to expect a crash, then when
5217 ours fails to crash, we would know that the bug was not happening for
5218 us. If you had not told us to expect a crash, then we would not be able
5219 to draw any conclusion from our observations.
5222 If you wish to suggest changes to the source, send us context diffs, as
5223 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
5224 option. Always send diffs from the old file to the new file. If you
5225 wish to discuss something in the @command{ld} source, refer to it by
5226 context, not by line number.
5228 The line numbers in our development sources will not match those in your
5229 sources. Your line numbers would convey no useful information to us.
5232 Here are some things that are not necessary:
5236 A description of the envelope of the bug.
5238 Often people who encounter a bug spend a lot of time investigating
5239 which changes to the input file will make the bug go away and which
5240 changes will not affect it.
5242 This is often time consuming and not very useful, because the way we
5243 will find the bug is by running a single example under the debugger
5244 with breakpoints, not by pure deduction from a series of examples.
5245 We recommend that you save your time for something else.
5247 Of course, if you can find a simpler example to report @emph{instead}
5248 of the original one, that is a convenience for us. Errors in the
5249 output will be easier to spot, running under the debugger will take
5250 less time, and so on.
5252 However, simplification is not vital; if you do not want to do this,
5253 report the bug anyway and send us the entire test case you used.
5256 A patch for the bug.
5258 A patch for the bug does help us if it is a good one. But do not omit
5259 the necessary information, such as the test case, on the assumption that
5260 a patch is all we need. We might see problems with your patch and decide
5261 to fix the problem another way, or we might not understand it at all.
5263 Sometimes with programs as complicated as the binary utilities it is
5264 very hard to construct an example that will make the program follow a
5265 certain path through the code. If you do not send us the example, we
5266 will not be able to construct one, so we will not be able to verify that
5269 And if we cannot understand what bug you are trying to fix, or why your
5270 patch should be an improvement, we will not install it. A test case will
5271 help us to understand.
5274 A guess about what the bug is or what it depends on.
5276 Such guesses are usually wrong. Even we cannot guess right about such
5277 things without first using the debugger to find the facts.
5280 @node GNU Free Documentation License
5281 @appendix GNU Free Documentation License
5285 @node Binutils Index
5286 @unnumbered Binutils Index