1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
10 * Binutils: (binutils). The GNU binary utilities.
11 * ar: (binutils)ar. Create, modify, and extract from archives
12 * nm: (binutils)nm. List symbols from object files
13 * objcopy: (binutils)objcopy. Copy and translate object files
14 * objdump: (binutils)objdump. Display information from object files
15 * ranlib: (binutils)ranlib. Generate index to archive contents
16 * readelf: (binutils)readelf. Display the contents of ELF format files.
17 * size: (binutils)size. List section sizes and total size
18 * strings: (binutils)strings. List printable strings from files
19 * strip: (binutils)strip. Discard symbols
20 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
21 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
22 * addr2line: (binutils)addr2line. Convert addresses to file and line
23 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
24 * windres: (binutils)windres. Manipulate Windows resources
25 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
31 @c man begin COPYRIGHT
32 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
33 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
35 Permission is granted to copy, distribute and/or modify this document
36 under the terms of the GNU Free Documentation License, Version 1.1
37 or any later version published by the Free Software Foundation;
38 with no Invariant Sections, with no Front-Cover Texts, and with no
39 Back-Cover Texts. A copy of the license is included in the
40 section entitled ``GNU Free Documentation License''.
44 Permission is granted to process this file through TeX and print the
45 results, provided the printed document carries a copying permission
46 notice identical to this one except for the removal of this paragraph
47 (this paragraph not being relevant to the printed manual).
54 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
57 @c Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
58 @c 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
60 @c This text may be freely distributed under the terms of the GNU
61 @c Free Documentation License.
64 @setchapternewpage odd
65 @settitle @sc{gnu} Binary Utilities
68 @title The @sc{gnu} Binary Utilities
69 @subtitle Version @value{VERSION}
71 @subtitle @value{UPDATED}
72 @author Roland H. Pesch
73 @author Jeffrey M. Osier
74 @author Cygnus Support
78 {\parskip=0pt \hfill Cygnus Support\par \hfill
79 \TeX{}info \texinfoversion\par }
82 @vskip 0pt plus 1filll
83 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
84 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
86 Permission is granted to copy, distribute and/or modify this document
87 under the terms of the GNU Free Documentation License, Version 1.1
88 or any later version published by the Free Software Foundation;
89 with no Invariant Sections, with no Front-Cover Texts, and with no
90 Back-Cover Texts. A copy of the license is included in the
91 section entitled ``GNU Free Documentation License''.
99 This brief manual contains documentation for the @sc{gnu} binary
100 utilities (collectively version @value{VERSION}):
105 Create, modify, and extract from archives
108 List symbols from object files
111 Copy and translate object files
114 Display information from object files
117 Generate index to archive contents
120 Display the contents of ELF format files.
123 List file section sizes and total size
126 List printable strings from files
132 Demangle encoded C++ symbols (on MS-DOS, this program is named
136 Convert addresses into file names and line numbers
139 Convert object code into a Netware Loadable Module
142 Manipulate Windows resources
145 Create the files needed to build and use Dynamic Link Libraries
149 This document is distributed under the terms of the GNU Free
150 Documentation License. A copy of the license is included in the
151 section entitled "GNU Free Documentation License".
154 * ar:: Create, modify, and extract from archives
155 * nm:: List symbols from object files
156 * objcopy:: Copy and translate object files
157 * objdump:: Display information from object files
158 * ranlib:: Generate index to archive contents
159 * readelf:: Display the contents of ELF format files.
160 * size:: List section sizes and total size
161 * strings:: List printable strings from files
162 * strip:: Discard symbols
163 * c++filt:: Filter to demangle encoded C++ symbols
164 * cxxfilt: c++filt. MS-DOS name for c++filt
165 * addr2line:: Convert addresses to file and line
166 * nlmconv:: Converts object code into an NLM
167 * windres:: Manipulate Windows resources
168 * dlltool:: Create files needed to build and use DLLs
169 * Common Options:: Command-line options for all utilities
170 * Selecting The Target System:: How these utilities determine the target.
171 * Reporting Bugs:: Reporting Bugs
172 * GNU Free Documentation License:: GNU Free Documentation License
181 @cindex collections of files
183 @c man title ar create, modify, and extract from archives
186 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
187 ar -M [ <mri-script ]
190 @c man begin DESCRIPTION ar
192 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
193 archives. An @dfn{archive} is a single file holding a collection of
194 other files in a structure that makes it possible to retrieve
195 the original individual files (called @dfn{members} of the archive).
197 The original files' contents, mode (permissions), timestamp, owner, and
198 group are preserved in the archive, and can be restored on
202 @sc{gnu} @command{ar} can maintain archives whose members have names of any
203 length; however, depending on how @command{ar} is configured on your
204 system, a limit on member-name length may be imposed for compatibility
205 with archive formats maintained with other tools. If it exists, the
206 limit is often 15 characters (typical of formats related to a.out) or 16
207 characters (typical of formats related to coff).
210 @command{ar} is considered a binary utility because archives of this sort
211 are most often used as @dfn{libraries} holding commonly needed
215 @command{ar} creates an index to the symbols defined in relocatable
216 object modules in the archive when you specify the modifier @samp{s}.
217 Once created, this index is updated in the archive whenever @command{ar}
218 makes a change to its contents (save for the @samp{q} update operation).
219 An archive with such an index speeds up linking to the library, and
220 allows routines in the library to call each other without regard to
221 their placement in the archive.
223 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
224 table. If an archive lacks the table, another form of @command{ar} called
225 @command{ranlib} can be used to add just the table.
227 @cindex compatibility, @command{ar}
228 @cindex @command{ar} compatibility
229 @sc{gnu} @command{ar} is designed to be compatible with two different
230 facilities. You can control its activity using command-line options,
231 like the different varieties of @command{ar} on Unix systems; or, if you
232 specify the single command-line option @option{-M}, you can control it
233 with a script supplied via standard input, like the MRI ``librarian''
239 * ar cmdline:: Controlling @command{ar} on the command line
240 * ar scripts:: Controlling @command{ar} with a script
245 @section Controlling @command{ar} on the Command Line
248 @c man begin SYNOPSIS ar
249 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
253 @cindex Unix compatibility, @command{ar}
254 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
255 arguments to execute: one keyletter specifying the @emph{operation}
256 (optionally accompanied by other keyletters specifying
257 @emph{modifiers}), and the archive name to act on.
259 Most operations can also accept further @var{member} arguments,
260 specifying particular files to operate on.
262 @c man begin OPTIONS ar
264 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
265 flags @var{mod} in any order, within the first command-line argument.
267 If you wish, you may begin the first command-line argument with a
270 @cindex operations on archive
271 The @var{p} keyletter specifies what operation to execute; it may be
272 any of the following, but you must specify only one of them:
276 @cindex deleting from archive
277 @emph{Delete} modules from the archive. Specify the names of modules to
278 be deleted as @var{member}@dots{}; the archive is untouched if you
279 specify no files to delete.
281 If you specify the @samp{v} modifier, @command{ar} lists each module
285 @cindex moving in archive
286 Use this operation to @emph{move} members in an archive.
288 The ordering of members in an archive can make a difference in how
289 programs are linked using the library, if a symbol is defined in more
292 If no modifiers are used with @code{m}, any members you name in the
293 @var{member} arguments are moved to the @emph{end} of the archive;
294 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
295 specified place instead.
298 @cindex printing from archive
299 @emph{Print} the specified members of the archive, to the standard
300 output file. If the @samp{v} modifier is specified, show the member
301 name before copying its contents to standard output.
303 If you specify no @var{member} arguments, all the files in the archive are
307 @cindex quick append to archive
308 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
309 @var{archive}, without checking for replacement.
311 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
312 operation; new members are always placed at the end of the archive.
314 The modifier @samp{v} makes @command{ar} list each file as it is appended.
316 Since the point of this operation is speed, the archive's symbol table
317 index is not updated, even if it already existed; you can use @samp{ar s} or
318 @command{ranlib} explicitly to update the symbol table index.
320 However, too many different systems assume quick append rebuilds the
321 index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
324 @cindex replacement in archive
325 Insert the files @var{member}@dots{} into @var{archive} (with
326 @emph{replacement}). This operation differs from @samp{q} in that any
327 previously existing members are deleted if their names match those being
330 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
331 displays an error message, and leaves undisturbed any existing members
332 of the archive matching that name.
334 By default, new members are added at the end of the file; but you may
335 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
336 placement relative to some existing member.
338 The modifier @samp{v} used with this operation elicits a line of
339 output for each file inserted, along with one of the letters @samp{a} or
340 @samp{r} to indicate whether the file was appended (no old member
341 deleted) or replaced.
344 @cindex contents of archive
345 Display a @emph{table} listing the contents of @var{archive}, or those
346 of the files listed in @var{member}@dots{} that are present in the
347 archive. Normally only the member name is shown; if you also want to
348 see the modes (permissions), timestamp, owner, group, and size, you can
349 request that by also specifying the @samp{v} modifier.
351 If you do not specify a @var{member}, all files in the archive
354 @cindex repeated names in archive
355 @cindex name duplication in archive
356 If there is more than one file with the same name (say, @samp{fie}) in
357 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
358 first instance; to see them all, you must ask for a complete
359 listing---in our example, @samp{ar t b.a}.
360 @c WRS only; per Gumby, this is implementation-dependent, and in a more
361 @c recent case in fact works the other way.
364 @cindex extract from archive
365 @emph{Extract} members (named @var{member}) from the archive. You can
366 use the @samp{v} modifier with this operation, to request that
367 @command{ar} list each name as it extracts it.
369 If you do not specify a @var{member}, all files in the archive
374 A number of modifiers (@var{mod}) may immediately follow the @var{p}
375 keyletter, to specify variations on an operation's behavior:
379 @cindex relative placement in archive
380 Add new files @emph{after} an existing member of the
381 archive. If you use the modifier @samp{a}, the name of an existing archive
382 member must be present as the @var{relpos} argument, before the
383 @var{archive} specification.
386 Add new files @emph{before} an existing member of the
387 archive. If you use the modifier @samp{b}, the name of an existing archive
388 member must be present as the @var{relpos} argument, before the
389 @var{archive} specification. (same as @samp{i}).
392 @cindex creating archives
393 @emph{Create} the archive. The specified @var{archive} is always
394 created if it did not exist, when you request an update. But a warning is
395 issued unless you specify in advance that you expect to create it, by
399 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
400 names of any length. This will cause it to create archives which are
401 not compatible with the native @command{ar} program on some systems. If
402 this is a concern, the @samp{f} modifier may be used to truncate file
403 names when putting them in the archive.
406 Insert new files @emph{before} an existing member of the
407 archive. If you use the modifier @samp{i}, the name of an existing archive
408 member must be present as the @var{relpos} argument, before the
409 @var{archive} specification. (same as @samp{b}).
412 This modifier is accepted but not used.
413 @c whaffor ar l modifier??? presumably compat; with
414 @c what???---doc@@cygnus.com, 25jan91
417 Uses the @var{count} parameter. This is used if there are multiple
418 entries in the archive with the same name. Extract or delete instance
419 @var{count} of the given name from the archive.
422 @cindex dates in archive
423 Preserve the @emph{original} dates of members when extracting them. If
424 you do not specify this modifier, files extracted from the archive
425 are stamped with the time of extraction.
428 Use the full path name when matching names in the archive. @sc{gnu}
429 @command{ar} can not create an archive with a full path name (such archives
430 are not POSIX complaint), but other archive creators can. This option
431 will cause @sc{gnu} @command{ar} to match file names using a complete path
432 name, which can be convenient when extracting a single file from an
433 archive created by another tool.
436 @cindex writing archive index
437 Write an object-file index into the archive, or update an existing one,
438 even if no other change is made to the archive. You may use this modifier
439 flag either with any operation, or alone. Running @samp{ar s} on an
440 archive is equivalent to running @samp{ranlib} on it.
443 @cindex not writing archive index
444 Do not generate an archive symbol table. This can speed up building a
445 large library in several steps. The resulting archive can not be used
446 with the linker. In order to build a symbol table, you must omit the
447 @samp{S} modifier on the last execution of @samp{ar}, or you must run
448 @samp{ranlib} on the archive.
451 @cindex updating an archive
452 Normally, @samp{ar r}@dots{} inserts all files
453 listed into the archive. If you would like to insert @emph{only} those
454 of the files you list that are newer than existing members of the same
455 names, use this modifier. The @samp{u} modifier is allowed only for the
456 operation @samp{r} (replace). In particular, the combination @samp{qu} is
457 not allowed, since checking the timestamps would lose any speed
458 advantage from the operation @samp{q}.
461 This modifier requests the @emph{verbose} version of an operation. Many
462 operations display additional information, such as filenames processed,
463 when the modifier @samp{v} is appended.
466 This modifier shows the version number of @command{ar}.
469 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
470 compatibility with AIX. The behaviour produced by this option is the
471 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
472 @samp{-X} options; in particular, it does not support @option{-X32}
473 which is the default for AIX @command{ar}.
478 @c man begin SEEALSO ar
479 nm(1), ranlib(1), and the Info entries for @file{binutils}.
484 @section Controlling @command{ar} with a Script
487 ar -M [ <@var{script} ]
490 @cindex MRI compatibility, @command{ar}
491 @cindex scripts, @command{ar}
492 If you use the single command-line option @samp{-M} with @command{ar}, you
493 can control its operation with a rudimentary command language. This
494 form of @command{ar} operates interactively if standard input is coming
495 directly from a terminal. During interactive use, @command{ar} prompts for
496 input (the prompt is @samp{AR >}), and continues executing even after
497 errors. If you redirect standard input to a script file, no prompts are
498 issued, and @command{ar} abandons execution (with a nonzero exit code)
501 The @command{ar} command language is @emph{not} designed to be equivalent
502 to the command-line options; in fact, it provides somewhat less control
503 over archives. The only purpose of the command language is to ease the
504 transition to @sc{gnu} @command{ar} for developers who already have scripts
505 written for the MRI ``librarian'' program.
507 The syntax for the @command{ar} command language is straightforward:
510 commands are recognized in upper or lower case; for example, @code{LIST}
511 is the same as @code{list}. In the following descriptions, commands are
512 shown in upper case for clarity.
515 a single command may appear on each line; it is the first word on the
519 empty lines are allowed, and have no effect.
522 comments are allowed; text after either of the characters @samp{*}
523 or @samp{;} is ignored.
526 Whenever you use a list of names as part of the argument to an @command{ar}
527 command, you can separate the individual names with either commas or
528 blanks. Commas are shown in the explanations below, for clarity.
531 @samp{+} is used as a line continuation character; if @samp{+} appears
532 at the end of a line, the text on the following line is considered part
533 of the current command.
536 Here are the commands you can use in @command{ar} scripts, or when using
537 @command{ar} interactively. Three of them have special significance:
539 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
540 a temporary file required for most of the other commands.
542 @code{SAVE} commits the changes so far specified by the script. Prior
543 to @code{SAVE}, commands affect only the temporary copy of the current
547 @item ADDLIB @var{archive}
548 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
549 Add all the contents of @var{archive} (or, if specified, each named
550 @var{module} from @var{archive}) to the current archive.
552 Requires prior use of @code{OPEN} or @code{CREATE}.
554 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
555 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
556 @c else like "ar q..."
557 Add each named @var{member} as a module in the current archive.
559 Requires prior use of @code{OPEN} or @code{CREATE}.
562 Discard the contents of the current archive, canceling the effect of
563 any operations since the last @code{SAVE}. May be executed (with no
564 effect) even if no current archive is specified.
566 @item CREATE @var{archive}
567 Creates an archive, and makes it the current archive (required for many
568 other commands). The new archive is created with a temporary name; it
569 is not actually saved as @var{archive} until you use @code{SAVE}.
570 You can overwrite existing archives; similarly, the contents of any
571 existing file named @var{archive} will not be destroyed until @code{SAVE}.
573 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
574 Delete each listed @var{module} from the current archive; equivalent to
575 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
577 Requires prior use of @code{OPEN} or @code{CREATE}.
579 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
580 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
581 List each named @var{module} present in @var{archive}. The separate
582 command @code{VERBOSE} specifies the form of the output: when verbose
583 output is off, output is like that of @samp{ar -t @var{archive}
584 @var{module}@dots{}}. When verbose output is on, the listing is like
585 @samp{ar -tv @var{archive} @var{module}@dots{}}.
587 Output normally goes to the standard output stream; however, if you
588 specify @var{outputfile} as a final argument, @command{ar} directs the
592 Exit from @command{ar}, with a @code{0} exit code to indicate successful
593 completion. This command does not save the output file; if you have
594 changed the current archive since the last @code{SAVE} command, those
597 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
598 Extract each named @var{module} from the current archive, writing them
599 into the current directory as separate files. Equivalent to @samp{ar -x
600 @var{archive} @var{module}@dots{}}.
602 Requires prior use of @code{OPEN} or @code{CREATE}.
605 @c FIXME Tokens but no commands???
612 Display full contents of the current archive, in ``verbose'' style
613 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
614 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
615 enhancement, rather than present for MRI compatibility.)
617 Requires prior use of @code{OPEN} or @code{CREATE}.
619 @item OPEN @var{archive}
620 Opens an existing archive for use as the current archive (required for
621 many other commands). Any changes as the result of subsequent commands
622 will not actually affect @var{archive} until you next use @code{SAVE}.
624 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
625 In the current archive, replace each existing @var{module} (named in
626 the @code{REPLACE} arguments) from files in the current working directory.
627 To execute this command without errors, both the file, and the module in
628 the current archive, must exist.
630 Requires prior use of @code{OPEN} or @code{CREATE}.
633 Toggle an internal flag governing the output from @code{DIRECTORY}.
634 When the flag is on, @code{DIRECTORY} output matches output from
635 @samp{ar -tv }@dots{}.
638 Commit your changes to the current archive, and actually save it as a
639 file with the name specified in the last @code{CREATE} or @code{OPEN}
642 Requires prior use of @code{OPEN} or @code{CREATE}.
651 The @sc{gnu} linker @command{ld} is now described in a separate manual.
652 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
660 @c man title nm list symbols from object files
663 @c man begin SYNOPSIS nm
664 nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}]
665 [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}]
666 [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}]
667 [@option{-A}|@option{-o}|@option{--print-file-name}][@option{--special-syms}]
668 [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}]
669 [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}]
670 [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}]
671 [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}]
672 [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}]
673 [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}]
677 @c man begin DESCRIPTION nm
678 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
679 If no object files are listed as arguments, @command{nm} assumes the file
682 For each symbol, @command{nm} shows:
686 The symbol value, in the radix selected by options (see below), or
687 hexadecimal by default.
690 The symbol type. At least the following types are used; others are, as
691 well, depending on the object file format. If lowercase, the symbol is
692 local; if uppercase, the symbol is global (external).
694 @c Some more detail on exactly what these symbol types are used for
698 The symbol's value is absolute, and will not be changed by further
702 The symbol is in the uninitialized data section (known as BSS).
705 The symbol is common. Common symbols are uninitialized data. When
706 linking, multiple common symbols may appear with the same name. If the
707 symbol is defined anywhere, the common symbols are treated as undefined
710 For more details on common symbols, see the discussion of
711 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
715 The symbol is in the initialized data section.
718 The symbol is in an initialized data section for small objects. Some
719 object file formats permit more efficient access to small data objects,
720 such as a global int variable as opposed to a large global array.
723 The symbol is an indirect reference to another symbol. This is a @sc{gnu}
724 extension to the a.out object file format which is rarely used.
727 The symbol is a debugging symbol.
730 The symbol is in a read only data section.
733 The symbol is in an uninitialized data section for small objects.
736 The symbol is in the text (code) section.
739 The symbol is undefined.
742 The symbol is a weak object. When a weak defined symbol is linked with
743 a normal defined symbol, the normal defined symbol is used with no error.
744 When a weak undefined symbol is linked and the symbol is not defined,
745 the value of the weak symbol becomes zero with no error.
748 The symbol is a weak symbol that has not been specifically tagged as a
749 weak object symbol. When a weak defined symbol is linked with a normal
750 defined symbol, the normal defined symbol is used with no error.
751 When a weak undefined symbol is linked and the symbol is not defined,
752 the value of the symbol is determined in a system-specific manner without
753 error. On some systems, uppercase indicates that a default value has been
758 The symbol is a stabs symbol in an a.out object file. In this case, the
759 next values printed are the stabs other field, the stabs desc field, and
760 the stab type. Stabs symbols are used to hold debugging information.
762 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
763 ``stabs'' debug format}.
767 The symbol type is unknown, or object file format specific.
776 @c man begin OPTIONS nm
777 The long and short forms of options, shown here as alternatives, are
783 @itemx --print-file-name
784 @cindex input file name
786 @cindex source file name
787 Precede each symbol by the name of the input file (or archive member)
788 in which it was found, rather than identifying the input file once only,
789 before all of its symbols.
793 @cindex debugging symbols
794 Display all symbols, even debugger-only symbols; normally these are not
798 @cindex @command{nm} format
799 @cindex @command{nm} compatibility
800 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
803 @itemx --demangle[=@var{style}]
804 @cindex demangling in nm
805 Decode (@dfn{demangle}) low-level symbol names into user-level names.
806 Besides removing any initial underscore prepended by the system, this
807 makes C++ function names readable. Different compilers have different
808 mangling styles. The optional demangling style argument can be used to
809 choose an appropriate demangling style for your compiler. @xref{c++filt},
810 for more information on demangling.
813 Do not demangle low-level symbol names. This is the default.
817 @cindex dynamic symbols
818 Display the dynamic symbols rather than the normal symbols. This is
819 only meaningful for dynamic objects, such as certain types of shared
822 @item -f @var{format}
823 @itemx --format=@var{format}
824 @cindex @command{nm} format
825 @cindex @command{nm} compatibility
826 Use the output format @var{format}, which can be @code{bsd},
827 @code{sysv}, or @code{posix}. The default is @code{bsd}.
828 Only the first character of @var{format} is significant; it can be
829 either upper or lower case.
833 @cindex external symbols
834 Display only external symbols.
837 @itemx --line-numbers
838 @cindex symbol line numbers
839 For each symbol, use debugging information to try to find a filename and
840 line number. For a defined symbol, look for the line number of the
841 address of the symbol. For an undefined symbol, look for the line
842 number of a relocation entry which refers to the symbol. If line number
843 information can be found, print it after the other symbol information.
847 @itemx --numeric-sort
848 Sort symbols numerically by their addresses, rather than alphabetically
853 @cindex sorting symbols
854 Do not bother to sort the symbols in any order; print them in the order
859 Use the POSIX.2 standard output format instead of the default format.
860 Equivalent to @samp{-f posix}.
864 Print size, not the value, of defined symbols for the @code{bsd} output format.
868 @cindex symbol index, listing
869 When listing symbols from archive members, include the index: a mapping
870 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
871 contain definitions for which names.
874 @itemx --reverse-sort
875 Reverse the order of the sort (whether numeric or alphabetic); let the
879 Sort symbols by size. The size is computed as the difference between
880 the value of the symbol and the value of the symbol with the next higher
881 value. If the @code{bsd} output format is used the size of the symbol
882 is printed, rather than the value, and @samp{-S} must be used in order
883 both size and value to be printed.
886 Display symbols which have a target-specific special meaning. These
887 symbols are usually used by the target for some special processing and
888 are not normally helpful when included included in the normal symbol
889 lists. For example for ARM targets this option would skip the mapping
890 symbols used to mark transistions between ARM code, THUMB code and
894 @itemx --radix=@var{radix}
895 Use @var{radix} as the radix for printing the symbol values. It must be
896 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
898 @item --target=@var{bfdname}
899 @cindex object code format
900 Specify an object code format other than your system's default format.
901 @xref{Target Selection}, for more information.
904 @itemx --undefined-only
905 @cindex external symbols
906 @cindex undefined symbols
907 Display only undefined symbols (those external to each object file).
910 @cindex external symbols
911 @cindex undefined symbols
912 Display only defined symbols for each object file.
916 Show the version number of @command{nm} and exit.
919 This option is ignored for compatibility with the AIX version of
920 @command{nm}. It takes one parameter which must be the string
921 @option{32_64}. The default mode of AIX @command{nm} corresponds
922 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
925 Show a summary of the options to @command{nm} and exit.
931 @c man begin SEEALSO nm
932 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
939 @c man title objcopy copy and translate object files
942 @c man begin SYNOPSIS objcopy
943 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
944 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
945 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
946 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
947 [@option{-S}|@option{--strip-all}]
948 [@option{-g}|@option{--strip-debug}]
949 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
950 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
951 [@option{--strip-unneeded-symbol=}@var{symbolname}]
952 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
953 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
954 [@option{--globalize-symbol=}@var{symbolname}]
955 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
956 [@option{-w}|@option{--wildcard}]
957 [@option{-x}|@option{--discard-all}]
958 [@option{-X}|@option{--discard-locals}]
959 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
960 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
961 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
962 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
963 [@option{-p}|@option{--preserve-dates}]
964 [@option{--debugging}]
965 [@option{--gap-fill=}@var{val}]
966 [@option{--pad-to=}@var{address}]
967 [@option{--set-start=}@var{val}]
968 [@option{--adjust-start=}@var{incr}]
969 [@option{--change-addresses=}@var{incr}]
970 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
971 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
972 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
973 [@option{--change-warnings}] [@option{--no-change-warnings}]
974 [@option{--set-section-flags} @var{section}=@var{flags}]
975 [@option{--add-section} @var{sectionname}=@var{filename}]
976 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
977 [@option{--change-leading-char}] [@option{--remove-leading-char}]
978 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
979 [@option{--redefine-sym} @var{old}=@var{new}]
980 [@option{--redefine-syms=}@var{filename}]
982 [@option{--keep-symbols=}@var{filename}]
983 [@option{--strip-symbols=}@var{filename}]
984 [@option{--strip-unneeded-symbols=}@var{filename}]
985 [@option{--keep-global-symbols=}@var{filename}]
986 [@option{--localize-symbols=}@var{filename}]
987 [@option{--globalize-symbols=}@var{filename}]
988 [@option{--weaken-symbols=}@var{filename}]
989 [@option{--alt-machine-code=}@var{index}]
990 [@option{--prefix-symbols=}@var{string}]
991 [@option{--prefix-sections=}@var{string}]
992 [@option{--prefix-alloc-sections=}@var{string}]
993 [@option{--add-gnu-debuglink=}@var{path-to-file}]
994 [@option{--keep-file-symbols}]
995 [@option{--only-keep-debug}]
996 [@option{--writable-text}]
997 [@option{--readonly-text}]
1000 [@option{-v}|@option{--verbose}]
1001 [@option{-V}|@option{--version}]
1002 [@option{--help}] [@option{--info}]
1003 @var{infile} [@var{outfile}]
1007 @c man begin DESCRIPTION objcopy
1008 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1009 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1010 read and write the object files. It can write the destination object
1011 file in a format different from that of the source object file. The
1012 exact behavior of @command{objcopy} is controlled by command-line options.
1013 Note that @command{objcopy} should be able to copy a fully linked file
1014 between any two formats. However, copying a relocatable object file
1015 between any two formats may not work as expected.
1017 @command{objcopy} creates temporary files to do its translations and
1018 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1019 translation work; it has access to all the formats described in @sc{bfd}
1020 and thus is able to recognize most formats without being told
1021 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1023 @command{objcopy} can be used to generate S-records by using an output
1024 target of @samp{srec} (e.g., use @samp{-O srec}).
1026 @command{objcopy} can be used to generate a raw binary file by using an
1027 output target of @samp{binary} (e.g., use @option{-O binary}). When
1028 @command{objcopy} generates a raw binary file, it will essentially produce
1029 a memory dump of the contents of the input object file. All symbols and
1030 relocation information will be discarded. The memory dump will start at
1031 the load address of the lowest section copied into the output file.
1033 When generating an S-record or a raw binary file, it may be helpful to
1034 use @option{-S} to remove sections containing debugging information. In
1035 some cases @option{-R} will be useful to remove sections which contain
1036 information that is not needed by the binary file.
1038 Note---@command{objcopy} is not able to change the endianness of its input
1039 files. If the input format has an endianness (some formats do not),
1040 @command{objcopy} can only copy the inputs into file formats that have the
1041 same endianness or which have no endianness (e.g., @samp{srec}).
1045 @c man begin OPTIONS objcopy
1049 @itemx @var{outfile}
1050 The input and output files, respectively.
1051 If you do not specify @var{outfile}, @command{objcopy} creates a
1052 temporary file and destructively renames the result with
1053 the name of @var{infile}.
1055 @item -I @var{bfdname}
1056 @itemx --input-target=@var{bfdname}
1057 Consider the source file's object format to be @var{bfdname}, rather than
1058 attempting to deduce it. @xref{Target Selection}, for more information.
1060 @item -O @var{bfdname}
1061 @itemx --output-target=@var{bfdname}
1062 Write the output file using the object format @var{bfdname}.
1063 @xref{Target Selection}, for more information.
1065 @item -F @var{bfdname}
1066 @itemx --target=@var{bfdname}
1067 Use @var{bfdname} as the object format for both the input and the output
1068 file; i.e., simply transfer data from source to destination with no
1069 translation. @xref{Target Selection}, for more information.
1071 @item -B @var{bfdarch}
1072 @itemx --binary-architecture=@var{bfdarch}
1073 Useful when transforming a raw binary input file into an object file.
1074 In this case the output architecture can be set to @var{bfdarch}. This
1075 option will be ignored if the input file has a known @var{bfdarch}. You
1076 can access this binary data inside a program by referencing the special
1077 symbols that are created by the conversion process. These symbols are
1078 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1079 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1080 an object file and then access it in your code using these symbols.
1082 @item -j @var{sectionname}
1083 @itemx --only-section=@var{sectionname}
1084 Copy only the named section from the input file to the output file.
1085 This option may be given more than once. Note that using this option
1086 inappropriately may make the output file unusable.
1088 @item -R @var{sectionname}
1089 @itemx --remove-section=@var{sectionname}
1090 Remove any section named @var{sectionname} from the output file. This
1091 option may be given more than once. Note that using this option
1092 inappropriately may make the output file unusable.
1096 Do not copy relocation and symbol information from the source file.
1099 @itemx --strip-debug
1100 Do not copy debugging symbols or sections from the source file.
1102 @item --strip-unneeded
1103 Strip all symbols that are not needed for relocation processing.
1105 @item -K @var{symbolname}
1106 @itemx --keep-symbol=@var{symbolname}
1107 When stripping symbols, keep symbol @var{symbolname} even if it would
1108 normally be stripped. This option may be given more than once.
1110 @item -N @var{symbolname}
1111 @itemx --strip-symbol=@var{symbolname}
1112 Do not copy symbol @var{symbolname} from the source file. This option
1113 may be given more than once.
1115 @item --strip-unneeded-symbol=@var{symbolname}
1116 Do not copy symbol @var{symbolname} from the source file unless it is needed
1117 by a relocation. This option may be given more than once.
1119 @item -G @var{symbolname}
1120 @itemx --keep-global-symbol=@var{symbolname}
1121 Keep only symbol @var{symbolname} global. Make all other symbols local
1122 to the file, so that they are not visible externally. This option may
1123 be given more than once.
1125 @item -L @var{symbolname}
1126 @itemx --localize-symbol=@var{symbolname}
1127 Make symbol @var{symbolname} local to the file, so that it is not
1128 visible externally. This option may be given more than once.
1130 @item -W @var{symbolname}
1131 @itemx --weaken-symbol=@var{symbolname}
1132 Make symbol @var{symbolname} weak. This option may be given more than once.
1134 @item --globalize-symbol=@var{symbolname}
1135 Give symbol @var{symbolname} global scoping so that it is visible
1136 outside of the file in which it is defined. This option may be given
1141 Permit regular expressions in @var{symbolname}s used in other command
1142 line options. The question mark (?), asterisk (*), backslash (\) and
1143 square brackets ([]) operators can be used anywhere in the symbol
1144 name. If the first character of the symbol name is the exclamation
1145 point (!) then the sense of the switch is reversed for that symbol.
1152 would cause objcopy to weaken all symbols that start with ``fo''
1153 except for the symbol ``foo''.
1156 @itemx --discard-all
1157 Do not copy non-global symbols from the source file.
1158 @c FIXME any reason to prefer "non-global" to "local" here?
1161 @itemx --discard-locals
1162 Do not copy compiler-generated local symbols.
1163 (These usually start with @samp{L} or @samp{.}.)
1166 @itemx --byte=@var{byte}
1167 Keep only every @var{byte}th byte of the input file (header data is not
1168 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1169 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1170 option, or the default of 4. This option is useful for creating files
1171 to program @sc{rom}. It is typically used with an @code{srec} output
1174 @item -i @var{interleave}
1175 @itemx --interleave=@var{interleave}
1176 Only copy one out of every @var{interleave} bytes. Select which byte to
1177 copy with the @option{-b} or @option{--byte} option. The default is 4.
1178 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1182 @itemx --preserve-dates
1183 Set the access and modification dates of the output file to be the same
1184 as those of the input file.
1187 Convert debugging information, if possible. This is not the default
1188 because only certain debugging formats are supported, and the
1189 conversion process can be time consuming.
1191 @item --gap-fill @var{val}
1192 Fill gaps between sections with @var{val}. This operation applies to
1193 the @emph{load address} (LMA) of the sections. It is done by increasing
1194 the size of the section with the lower address, and filling in the extra
1195 space created with @var{val}.
1197 @item --pad-to @var{address}
1198 Pad the output file up to the load address @var{address}. This is
1199 done by increasing the size of the last section. The extra space is
1200 filled in with the value specified by @option{--gap-fill} (default zero).
1202 @item --set-start @var{val}
1203 Set the start address of the new file to @var{val}. Not all object file
1204 formats support setting the start address.
1206 @item --change-start @var{incr}
1207 @itemx --adjust-start @var{incr}
1208 @cindex changing start address
1209 Change the start address by adding @var{incr}. Not all object file
1210 formats support setting the start address.
1212 @item --change-addresses @var{incr}
1213 @itemx --adjust-vma @var{incr}
1214 @cindex changing object addresses
1215 Change the VMA and LMA addresses of all sections, as well as the start
1216 address, by adding @var{incr}. Some object file formats do not permit
1217 section addresses to be changed arbitrarily. Note that this does not
1218 relocate the sections; if the program expects sections to be loaded at a
1219 certain address, and this option is used to change the sections such
1220 that they are loaded at a different address, the program may fail.
1222 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1223 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1224 @cindex changing section address
1225 Set or change both the VMA address and the LMA address of the named
1226 @var{section}. If @samp{=} is used, the section address is set to
1227 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1228 section address. See the comments under @option{--change-addresses},
1229 above. If @var{section} does not exist in the input file, a warning will
1230 be issued, unless @option{--no-change-warnings} is used.
1232 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1233 @cindex changing section LMA
1234 Set or change the LMA address of the named @var{section}. The LMA
1235 address is the address where the section will be loaded into memory at
1236 program load time. Normally this is the same as the VMA address, which
1237 is the address of the section at program run time, but on some systems,
1238 especially those where a program is held in ROM, the two can be
1239 different. If @samp{=} is used, the section address is set to
1240 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1241 section address. See the comments under @option{--change-addresses},
1242 above. If @var{section} does not exist in the input file, a warning
1243 will be issued, unless @option{--no-change-warnings} is used.
1245 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1246 @cindex changing section VMA
1247 Set or change the VMA address of the named @var{section}. The VMA
1248 address is the address where the section will be located once the
1249 program has started executing. Normally this is the same as the LMA
1250 address, which is the address where the section will be loaded into
1251 memory, but on some systems, especially those where a program is held in
1252 ROM, the two can be different. If @samp{=} is used, the section address
1253 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1254 from the section address. See the comments under
1255 @option{--change-addresses}, above. If @var{section} does not exist in
1256 the input file, a warning will be issued, unless
1257 @option{--no-change-warnings} is used.
1259 @item --change-warnings
1260 @itemx --adjust-warnings
1261 If @option{--change-section-address} or @option{--change-section-lma} or
1262 @option{--change-section-vma} is used, and the named section does not
1263 exist, issue a warning. This is the default.
1265 @item --no-change-warnings
1266 @itemx --no-adjust-warnings
1267 Do not issue a warning if @option{--change-section-address} or
1268 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1269 if the named section does not exist.
1271 @item --set-section-flags @var{section}=@var{flags}
1272 Set the flags for the named section. The @var{flags} argument is a
1273 comma separated string of flag names. The recognized names are
1274 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1275 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1276 @samp{debug}. You can set the @samp{contents} flag for a section which
1277 does not have contents, but it is not meaningful to clear the
1278 @samp{contents} flag of a section which does have contents--just remove
1279 the section instead. Not all flags are meaningful for all object file
1282 @item --add-section @var{sectionname}=@var{filename}
1283 Add a new section named @var{sectionname} while copying the file. The
1284 contents of the new section are taken from the file @var{filename}. The
1285 size of the section will be the size of the file. This option only
1286 works on file formats which can support sections with arbitrary names.
1288 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1289 Rename a section from @var{oldname} to @var{newname}, optionally
1290 changing the section's flags to @var{flags} in the process. This has
1291 the advantage over usng a linker script to perform the rename in that
1292 the output stays as an object file and does not become a linked
1295 This option is particularly helpful when the input format is binary,
1296 since this will always create a section called .data. If for example,
1297 you wanted instead to create a section called .rodata containing binary
1298 data you could use the following command line to achieve it:
1301 objcopy -I binary -O <output_format> -B <architecture> \
1302 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1303 <input_binary_file> <output_object_file>
1306 @item --change-leading-char
1307 Some object file formats use special characters at the start of
1308 symbols. The most common such character is underscore, which compilers
1309 often add before every symbol. This option tells @command{objcopy} to
1310 change the leading character of every symbol when it converts between
1311 object file formats. If the object file formats use the same leading
1312 character, this option has no effect. Otherwise, it will add a
1313 character, or remove a character, or change a character, as
1316 @item --remove-leading-char
1317 If the first character of a global symbol is a special symbol leading
1318 character used by the object file format, remove the character. The
1319 most common symbol leading character is underscore. This option will
1320 remove a leading underscore from all global symbols. This can be useful
1321 if you want to link together objects of different file formats with
1322 different conventions for symbol names. This is different from
1323 @option{--change-leading-char} because it always changes the symbol name
1324 when appropriate, regardless of the object file format of the output
1327 @item --srec-len=@var{ival}
1328 Meaningful only for srec output. Set the maximum length of the Srecords
1329 being produced to @var{ival}. This length covers both address, data and
1332 @item --srec-forceS3
1333 Meaningful only for srec output. Avoid generation of S1/S2 records,
1334 creating S3-only record format.
1336 @item --redefine-sym @var{old}=@var{new}
1337 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1338 when one is trying link two things together for which you have no
1339 source, and there are name collisions.
1341 @item --redefine-syms=@var{filename}
1342 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1343 listed in the file @var{filename}. @var{filename} is simply a flat file,
1344 with one symbol pair per line. Line comments may be introduced by the hash
1345 character. This option may be given more than once.
1348 Change all global symbols in the file to be weak. This can be useful
1349 when building an object which will be linked against other objects using
1350 the @option{-R} option to the linker. This option is only effective when
1351 using an object file format which supports weak symbols.
1353 @item --keep-symbols=@var{filename}
1354 Apply @option{--keep-symbol} option to each symbol listed in the file
1355 @var{filename}. @var{filename} is simply a flat file, with one symbol
1356 name per line. Line comments may be introduced by the hash character.
1357 This option may be given more than once.
1359 @item --strip-symbols=@var{filename}
1360 Apply @option{--strip-symbol} option to each symbol listed in the file
1361 @var{filename}. @var{filename} is simply a flat file, with one symbol
1362 name per line. Line comments may be introduced by the hash character.
1363 This option may be given more than once.
1365 @item --strip-unneeded-symbols=@var{filename}
1366 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1367 the file @var{filename}. @var{filename} is simply a flat file, with one
1368 symbol name per line. Line comments may be introduced by the hash
1369 character. This option may be given more than once.
1371 @item --keep-global-symbols=@var{filename}
1372 Apply @option{--keep-global-symbol} option to each symbol listed in the
1373 file @var{filename}. @var{filename} is simply a flat file, with one
1374 symbol name per line. Line comments may be introduced by the hash
1375 character. This option may be given more than once.
1377 @item --localize-symbols=@var{filename}
1378 Apply @option{--localize-symbol} option to each symbol listed in the file
1379 @var{filename}. @var{filename} is simply a flat file, with one symbol
1380 name per line. Line comments may be introduced by the hash character.
1381 This option may be given more than once.
1383 @item --globalize-symbols=@var{filename}
1384 Apply @option{--globalize-symbol} option to each symbol listed in the file
1385 @var{filename}. @var{filename} is simply a flat file, with one symbol
1386 name per line. Line comments may be introduced by the hash character.
1387 This option may be given more than once.
1389 @item --weaken-symbols=@var{filename}
1390 Apply @option{--weaken-symbol} option to each symbol listed in the file
1391 @var{filename}. @var{filename} is simply a flat file, with one symbol
1392 name per line. Line comments may be introduced by the hash character.
1393 This option may be given more than once.
1395 @item --alt-machine-code=@var{index}
1396 If the output architecture has alternate machine codes, use the
1397 @var{index}th code instead of the default one. This is useful in case
1398 a machine is assigned an official code and the tool-chain adopts the
1399 new code, but other applications still depend on the original code
1402 @item --writable-text
1403 Mark the output text as writable. This option isn't meaningful for all
1404 object file formats.
1406 @item --readonly-text
1407 Make the output text write protected. This option isn't meaningful for all
1408 object file formats.
1411 Mark the output file as demand paged. This option isn't meaningful for all
1412 object file formats.
1415 Mark the output file as impure. This option isn't meaningful for all
1416 object file formats.
1418 @item --prefix-symbols=@var{string}
1419 Prefix all symbols in the output file with @var{string}.
1421 @item --prefix-sections=@var{string}
1422 Prefix all section names in the output file with @var{string}.
1424 @item --prefix-alloc-sections=@var{string}
1425 Prefix all the names of all allocated sections in the output file with
1428 @item --add-gnu-debuglink=@var{path-to-file}
1429 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1430 and adds it to the output file.
1432 @item --keep-file-symbols
1433 When stripping a file, perhaps with @option{--strip-debug} or
1434 @option{--strip-unneeded}, retain any symbols specifying source file names,
1435 which would otherwise get stripped.
1437 @item --only-keep-debug
1438 Strip a file, removing contents of any sections that would not be
1439 stripped by @option{--strip-debug} and leaving the debugging sections
1442 The intention is that this option will be used in conjunction with
1443 @option{--add-gnu-debuglink} to create a two part executable. One a
1444 stripped binary which will occupy less space in RAM and in a
1445 distribution and the second a debugging information file which is only
1446 needed if debugging abilities are required. The suggested procedure
1447 to create these files is as follows:
1450 @item Link the executable as normal. Assuming that is is called
1452 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1453 create a file containing the debugging info.
1454 @item Run @code{objcopy --strip-debug foo} to create a
1455 stripped executable.
1456 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1457 to add a link to the debugging info into the stripped executable.
1460 Note - the choice of @code{.dbg} as an extension for the debug info
1461 file is arbitrary. Also the @code{--only-keep-debug} step is
1462 optional. You could instead do this:
1465 @item Link the executable as normal.
1466 @item Copy @code{foo} to @code{foo.full}
1467 @item Run @code{objcopy --strip-debug foo}
1468 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1471 i.e. the file pointed to by the @option{--add-gnu-debuglink} can be the
1472 full executable. It does not have to be a file created by the
1473 @option{--only-keep-debug} switch.
1477 Show the version number of @command{objcopy}.
1481 Verbose output: list all object files modified. In the case of
1482 archives, @samp{objcopy -V} lists all members of the archive.
1485 Show a summary of the options to @command{objcopy}.
1488 Display a list showing all architectures and object formats available.
1494 @c man begin SEEALSO objcopy
1495 ld(1), objdump(1), and the Info entries for @file{binutils}.
1502 @cindex object file information
1505 @c man title objdump display information from object files.
1508 @c man begin SYNOPSIS objdump
1509 objdump [@option{-a}|@option{--archive-headers}]
1510 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1511 [@option{-C}|@option{--demangle}[=@var{style}] ]
1512 [@option{-d}|@option{--disassemble}]
1513 [@option{-D}|@option{--disassemble-all}]
1514 [@option{-z}|@option{--disassemble-zeroes}]
1515 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1516 [@option{-f}|@option{--file-headers}]
1517 [@option{--file-start-context}]
1518 [@option{-g}|@option{--debugging}]
1519 [@option{-e}|@option{--debugging-tags}]
1520 [@option{-h}|@option{--section-headers}|@option{--headers}]
1521 [@option{-i}|@option{--info}]
1522 [@option{-j} @var{section}|@option{--section=}@var{section}]
1523 [@option{-l}|@option{--line-numbers}]
1524 [@option{-S}|@option{--source}]
1525 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1526 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1527 [@option{-p}|@option{--private-headers}]
1528 [@option{-r}|@option{--reloc}]
1529 [@option{-R}|@option{--dynamic-reloc}]
1530 [@option{-s}|@option{--full-contents}]
1531 [@option{-W}|@option{--dwarf}]
1532 [@option{-G}|@option{--stabs}]
1533 [@option{-t}|@option{--syms}]
1534 [@option{-T}|@option{--dynamic-syms}]
1535 [@option{-x}|@option{--all-headers}]
1536 [@option{-w}|@option{--wide}]
1537 [@option{--start-address=}@var{address}]
1538 [@option{--stop-address=}@var{address}]
1539 [@option{--prefix-addresses}]
1540 [@option{--[no-]show-raw-insn}]
1541 [@option{--adjust-vma=}@var{offset}]
1542 [@option{--special-syms}]
1543 [@option{-V}|@option{--version}]
1544 [@option{-H}|@option{--help}]
1545 @var{objfile}@dots{}
1549 @c man begin DESCRIPTION objdump
1551 @command{objdump} displays information about one or more object files.
1552 The options control what particular information to display. This
1553 information is mostly useful to programmers who are working on the
1554 compilation tools, as opposed to programmers who just want their
1555 program to compile and work.
1557 @var{objfile}@dots{} are the object files to be examined. When you
1558 specify archives, @command{objdump} shows information on each of the member
1563 @c man begin OPTIONS objdump
1565 The long and short forms of options, shown here as alternatives, are
1566 equivalent. At least one option from the list
1567 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1571 @itemx --archive-header
1572 @cindex archive headers
1573 If any of the @var{objfile} files are archives, display the archive
1574 header information (in a format similar to @samp{ls -l}). Besides the
1575 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1576 the object file format of each archive member.
1578 @item --adjust-vma=@var{offset}
1579 @cindex section addresses in objdump
1580 @cindex VMA in objdump
1581 When dumping information, first add @var{offset} to all the section
1582 addresses. This is useful if the section addresses do not correspond to
1583 the symbol table, which can happen when putting sections at particular
1584 addresses when using a format which can not represent section addresses,
1587 @item -b @var{bfdname}
1588 @itemx --target=@var{bfdname}
1589 @cindex object code format
1590 Specify that the object-code format for the object files is
1591 @var{bfdname}. This option may not be necessary; @var{objdump} can
1592 automatically recognize many formats.
1596 objdump -b oasys -m vax -h fu.o
1599 displays summary information from the section headers (@option{-h}) of
1600 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1601 file in the format produced by Oasys compilers. You can list the
1602 formats available with the @option{-i} option.
1603 @xref{Target Selection}, for more information.
1606 @itemx --demangle[=@var{style}]
1607 @cindex demangling in objdump
1608 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1609 Besides removing any initial underscore prepended by the system, this
1610 makes C++ function names readable. Different compilers have different
1611 mangling styles. The optional demangling style argument can be used to
1612 choose an appropriate demangling style for your compiler. @xref{c++filt},
1613 for more information on demangling.
1617 Display debugging information. This attempts to parse debugging
1618 information stored in the file and print it out using a C like syntax.
1619 Only certain types of debugging information have been implemented.
1620 Some other types are supported by @command{readelf -w}.
1624 @itemx --debugging-tags
1625 Like @option{-g}, but the information is generated in a format compatible
1629 @itemx --disassemble
1630 @cindex disassembling object code
1631 @cindex machine instructions
1632 Display the assembler mnemonics for the machine instructions from
1633 @var{objfile}. This option only disassembles those sections which are
1634 expected to contain instructions.
1637 @itemx --disassemble-all
1638 Like @option{-d}, but disassemble the contents of all sections, not just
1639 those expected to contain instructions.
1641 @item --prefix-addresses
1642 When disassembling, print the complete address on each line. This is
1643 the older disassembly format.
1647 @itemx --endian=@{big|little@}
1649 @cindex disassembly endianness
1650 Specify the endianness of the object files. This only affects
1651 disassembly. This can be useful when disassembling a file format which
1652 does not describe endianness information, such as S-records.
1655 @itemx --file-headers
1656 @cindex object file header
1657 Display summary information from the overall header of
1658 each of the @var{objfile} files.
1660 @item --file-start-context
1661 @cindex source code context
1662 Specify that when displaying interlisted source code/disassembly
1663 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1664 context to the start of the file.
1667 @itemx --section-headers
1669 @cindex section headers
1670 Display summary information from the section headers of the
1673 File segments may be relocated to nonstandard addresses, for example by
1674 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1675 @command{ld}. However, some object file formats, such as a.out, do not
1676 store the starting address of the file segments. In those situations,
1677 although @command{ld} relocates the sections correctly, using @samp{objdump
1678 -h} to list the file section headers cannot show the correct addresses.
1679 Instead, it shows the usual addresses, which are implicit for the
1684 Print a summary of the options to @command{objdump} and exit.
1688 @cindex architectures available
1689 @cindex object formats available
1690 Display a list showing all architectures and object formats available
1691 for specification with @option{-b} or @option{-m}.
1694 @itemx --section=@var{name}
1695 @cindex section information
1696 Display information only for section @var{name}.
1699 @itemx --line-numbers
1700 @cindex source filenames for object files
1701 Label the display (using debugging information) with the filename and
1702 source line numbers corresponding to the object code or relocs shown.
1703 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1705 @item -m @var{machine}
1706 @itemx --architecture=@var{machine}
1707 @cindex architecture
1708 @cindex disassembly architecture
1709 Specify the architecture to use when disassembling object files. This
1710 can be useful when disassembling object files which do not describe
1711 architecture information, such as S-records. You can list the available
1712 architectures with the @option{-i} option.
1714 @item -M @var{options}
1715 @itemx --disassembler-options=@var{options}
1716 Pass target specific information to the disassembler. Only supported on
1717 some targets. If it is necessary to specify more than one
1718 disassembler option then multiple @option{-M} options can be used or
1719 can be placed together into a comma separated list.
1721 If the target is an ARM architecture then this switch can be used to
1722 select which register name set is used during disassembler. Specifying
1723 @option{-M reg-names-std} (the default) will select the register names as
1724 used in ARM's instruction set documentation, but with register 13 called
1725 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1726 @option{-M reg-names-apcs} will select the name set used by the ARM
1727 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1728 just use @samp{r} followed by the register number.
1730 There are also two variants on the APCS register naming scheme enabled
1731 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1732 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1733 with the normal register names or the special register names).
1735 This option can also be used for ARM architectures to force the
1736 disassembler to interpret all instructions as Thumb instructions by
1737 using the switch @option{--disassembler-options=force-thumb}. This can be
1738 useful when attempting to disassemble thumb code produced by other
1741 For the x86, some of the options duplicate functions of the @option{-m}
1742 switch, but allow finer grained control. Multiple selections from the
1743 following may be specified as a comma separated string.
1744 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1745 the given architecture. @option{intel} and @option{att} select between
1746 intel syntax mode and AT&T syntax mode. @option{addr32},
1747 @option{addr16}, @option{data32} and @option{data16} specify the default
1748 address size and operand size. These four options will be overridden if
1749 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1750 option string. Lastly, @option{suffix}, when in AT&T mode,
1751 instructs the disassembler to print a mnemonic suffix even when the
1752 suffix could be inferred by the operands.
1754 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1755 disassembly of BookE instructions. @option{32} and @option{64} select
1756 PowerPC and PowerPC64 disassembly, respectively. @option{e300} selects
1757 disassembly for the e300 family.
1759 For MIPS, this option controls the printing of instruction mneumonic
1760 names and register names in disassembled instructions. Multiple
1761 selections from the following may be specified as a comma separated
1762 string, and invalid options are ignored:
1766 Print the 'raw' instruction mneumonic instead of some pseudo
1767 instruction mneumonic. I.E. print 'daddu' or 'or' instead of 'move',
1768 'sll' instead of 'nop', etc.
1770 @item gpr-names=@var{ABI}
1771 Print GPR (general-purpose register) names as appropriate
1772 for the specified ABI. By default, GPR names are selected according to
1773 the ABI of the binary being disassembled.
1775 @item fpr-names=@var{ABI}
1776 Print FPR (floating-point register) names as
1777 appropriate for the specified ABI. By default, FPR numbers are printed
1780 @item cp0-names=@var{ARCH}
1781 Print CP0 (system control coprocessor; coprocessor 0) register names
1782 as appropriate for the CPU or architecture specified by
1783 @var{ARCH}. By default, CP0 register names are selected according to
1784 the architecture and CPU of the binary being disassembled.
1786 @item hwr-names=@var{ARCH}
1787 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1788 as appropriate for the CPU or architecture specified by
1789 @var{ARCH}. By default, HWR names are selected according to
1790 the architecture and CPU of the binary being disassembled.
1792 @item reg-names=@var{ABI}
1793 Print GPR and FPR names as appropriate for the selected ABI.
1795 @item reg-names=@var{ARCH}
1796 Print CPU-specific register names (CP0 register and HWR names)
1797 as appropriate for the selected CPU or architecture.
1800 For any of the options listed above, @var{ABI} or
1801 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1802 rather than names, for the selected types of registers.
1803 You can list the available values of @var{ABI} and @var{ARCH} using
1804 the @option{--help} option.
1806 For VAX, you can specify function entry addresses with @option{-M
1807 entry:0xf00ba}. You can use this multiple times to properly
1808 disassemble VAX binary files that don't contain symbol tables (like
1809 ROM dumps). In these cases, the function entry mask would otherwise
1810 be decoded as VAX instructions, which would probably lead the the rest
1811 of the function being wrongly disassembled.
1814 @itemx --private-headers
1815 Print information that is specific to the object file format. The exact
1816 information printed depends upon the object file format. For some
1817 object file formats, no additional information is printed.
1821 @cindex relocation entries, in object file
1822 Print the relocation entries of the file. If used with @option{-d} or
1823 @option{-D}, the relocations are printed interspersed with the
1827 @itemx --dynamic-reloc
1828 @cindex dynamic relocation entries, in object file
1829 Print the dynamic relocation entries of the file. This is only
1830 meaningful for dynamic objects, such as certain types of shared
1834 @itemx --full-contents
1835 @cindex sections, full contents
1836 @cindex object file sections
1837 Display the full contents of any sections requested. By default all
1838 non-empty sections are displayed.
1842 @cindex source disassembly
1843 @cindex disassembly, with source
1844 Display source code intermixed with disassembly, if possible. Implies
1847 @item --show-raw-insn
1848 When disassembling instructions, print the instruction in hex as well as
1849 in symbolic form. This is the default except when
1850 @option{--prefix-addresses} is used.
1852 @item --no-show-raw-insn
1853 When disassembling instructions, do not print the instruction bytes.
1854 This is the default when @option{--prefix-addresses} is used.
1859 @cindex debug symbols
1860 Displays the contents of the DWARF debug sections in the file, if any
1867 @cindex debug symbols
1868 @cindex ELF object file format
1869 Display the full contents of any sections requested. Display the
1870 contents of the .stab and .stab.index and .stab.excl sections from an
1871 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1872 @code{.stab} debugging symbol-table entries are carried in an ELF
1873 section. In most other file formats, debugging symbol-table entries are
1874 interleaved with linkage symbols, and are visible in the @option{--syms}
1877 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1878 Overview,stabs.info, The ``stabs'' debug format}.
1881 @item --start-address=@var{address}
1882 @cindex start-address
1883 Start displaying data at the specified address. This affects the output
1884 of the @option{-d}, @option{-r} and @option{-s} options.
1886 @item --stop-address=@var{address}
1887 @cindex stop-address
1888 Stop displaying data at the specified address. This affects the output
1889 of the @option{-d}, @option{-r} and @option{-s} options.
1893 @cindex symbol table entries, printing
1894 Print the symbol table entries of the file.
1895 This is similar to the information provided by the @samp{nm} program.
1898 @itemx --dynamic-syms
1899 @cindex dynamic symbol table entries, printing
1900 Print the dynamic symbol table entries of the file. This is only
1901 meaningful for dynamic objects, such as certain types of shared
1902 libraries. This is similar to the information provided by the @samp{nm}
1903 program when given the @option{-D} (@option{--dynamic}) option.
1905 @item --special-syms
1906 When displaying symbols include those which the target considers to be
1907 special in some way and which would not normally be of interest to the
1912 Print the version number of @command{objdump} and exit.
1915 @itemx --all-headers
1916 @cindex all header information, object file
1917 @cindex header information, all
1918 Display all available header information, including the symbol table and
1919 relocation entries. Using @option{-x} is equivalent to specifying all of
1920 @option{-a -f -h -p -r -t}.
1924 @cindex wide output, printing
1925 Format some lines for output devices that have more than 80 columns.
1926 Also do not truncate symbol names when they are displayed.
1929 @itemx --disassemble-zeroes
1930 Normally the disassembly output will skip blocks of zeroes. This
1931 option directs the disassembler to disassemble those blocks, just like
1938 @c man begin SEEALSO objdump
1939 nm(1), readelf(1), and the Info entries for @file{binutils}.
1947 @cindex archive contents
1948 @cindex symbol index
1950 @c man title ranlib generate index to archive.
1953 @c man begin SYNOPSIS ranlib
1954 ranlib [@option{-vV}] @var{archive}
1958 @c man begin DESCRIPTION ranlib
1960 @command{ranlib} generates an index to the contents of an archive and
1961 stores it in the archive. The index lists each symbol defined by a
1962 member of an archive that is a relocatable object file.
1964 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1966 An archive with such an index speeds up linking to the library and
1967 allows routines in the library to call each other without regard to
1968 their placement in the archive.
1970 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
1971 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
1976 @c man begin OPTIONS ranlib
1982 Show the version number of @command{ranlib}.
1988 @c man begin SEEALSO ranlib
1989 ar(1), nm(1), and the Info entries for @file{binutils}.
1997 @cindex section sizes
1999 @c man title size list section sizes and total size.
2002 @c man begin SYNOPSIS size
2003 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2005 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2006 [@option{-t}|@option{--totals}]
2007 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2008 [@var{objfile}@dots{}]
2012 @c man begin DESCRIPTION size
2014 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2015 size---for each of the object or archive files @var{objfile} in its
2016 argument list. By default, one line of output is generated for each
2017 object file or each module in an archive.
2019 @var{objfile}@dots{} are the object files to be examined.
2020 If none are specified, the file @code{a.out} will be used.
2024 @c man begin OPTIONS size
2026 The command line options have the following meanings:
2031 @itemx --format=@var{compatibility}
2032 @cindex @command{size} display format
2033 Using one of these options, you can choose whether the output from @sc{gnu}
2034 @command{size} resembles output from System V @command{size} (using @option{-A},
2035 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2036 @option{--format=berkeley}). The default is the one-line format similar to
2038 @c Bonus for doc-source readers: you can also say --format=strange (or
2039 @c anything else that starts with 's') for sysv, and --format=boring (or
2040 @c anything else that starts with 'b') for Berkeley.
2042 Here is an example of the Berkeley (default) format of output from
2045 $ size --format=Berkeley ranlib size
2046 text data bss dec hex filename
2047 294880 81920 11592 388392 5ed28 ranlib
2048 294880 81920 11888 388688 5ee50 size
2052 This is the same data, but displayed closer to System V conventions:
2055 $ size --format=SysV ranlib size
2073 Show a summary of acceptable arguments and options.
2078 @itemx --radix=@var{number}
2079 @cindex @command{size} number format
2080 @cindex radix for section sizes
2081 Using one of these options, you can control whether the size of each
2082 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2083 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2084 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2085 values (8, 10, 16) are supported. The total size is always given in two
2086 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2087 octal and hexadecimal if you're using @option{-o}.
2091 Show totals of all objects listed (Berkeley format listing mode only).
2093 @item --target=@var{bfdname}
2094 @cindex object code format
2095 Specify that the object-code format for @var{objfile} is
2096 @var{bfdname}. This option may not be necessary; @command{size} can
2097 automatically recognize many formats.
2098 @xref{Target Selection}, for more information.
2102 Display the version number of @command{size}.
2108 @c man begin SEEALSO size
2109 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2116 @cindex listings strings
2117 @cindex printing strings
2118 @cindex strings, printing
2120 @c man title strings print the strings of printable characters in files.
2123 @c man begin SYNOPSIS strings
2124 strings [@option{-afov}] [@option{-}@var{min-len}]
2125 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2126 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2127 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2128 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2129 [@option{--target=}@var{bfdname}]
2130 [@option{--help}] [@option{--version}] @var{file}@dots{}
2134 @c man begin DESCRIPTION strings
2136 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2137 character sequences that are at least 4 characters long (or the number
2138 given with the options below) and are followed by an unprintable
2139 character. By default, it only prints the strings from the initialized
2140 and loaded sections of object files; for other types of files, it prints
2141 the strings from the whole file.
2143 @command{strings} is mainly useful for determining the contents of non-text
2148 @c man begin OPTIONS strings
2154 Do not scan only the initialized and loaded sections of object files;
2155 scan the whole files.
2158 @itemx --print-file-name
2159 Print the name of the file before each string.
2162 Print a summary of the program usage on the standard output and exit.
2164 @item -@var{min-len}
2165 @itemx -n @var{min-len}
2166 @itemx --bytes=@var{min-len}
2167 Print sequences of characters that are at least @var{min-len} characters
2168 long, instead of the default 4.
2171 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2172 act like @samp{-t d} instead. Since we can not be compatible with both
2173 ways, we simply chose one.
2175 @item -t @var{radix}
2176 @itemx --radix=@var{radix}
2177 Print the offset within the file before each string. The single
2178 character argument specifies the radix of the offset---@samp{o} for
2179 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2181 @item -e @var{encoding}
2182 @itemx --encoding=@var{encoding}
2183 Select the character encoding of the strings that are to be found.
2184 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2185 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2186 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2187 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2188 littleendian. Useful for finding wide character strings.
2190 @item --target=@var{bfdname}
2191 @cindex object code format
2192 Specify an object code format other than your system's default format.
2193 @xref{Target Selection}, for more information.
2197 Print the program version number on the standard output and exit.
2203 @c man begin SEEALSO strings
2204 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2205 and the Info entries for @file{binutils}.
2213 @cindex removing symbols
2214 @cindex discarding symbols
2215 @cindex symbols, discarding
2217 @c man title strip Discard symbols from object files.
2220 @c man begin SYNOPSIS strip
2221 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2222 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2223 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2224 [@option{-s}|@option{--strip-all}]
2225 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2226 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2227 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2228 [@option{-w}|@option{--wildcard}]
2229 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2230 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2231 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2232 [@option{--keep-file-symbols}]
2233 [@option{--only-keep-debug}]
2234 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2235 [@option{--help}] [@option{--info}]
2236 @var{objfile}@dots{}
2240 @c man begin DESCRIPTION strip
2242 @sc{gnu} @command{strip} discards all symbols from object files
2243 @var{objfile}. The list of object files may include archives.
2244 At least one object file must be given.
2246 @command{strip} modifies the files named in its argument,
2247 rather than writing modified copies under different names.
2251 @c man begin OPTIONS strip
2254 @item -F @var{bfdname}
2255 @itemx --target=@var{bfdname}
2256 Treat the original @var{objfile} as a file with the object
2257 code format @var{bfdname}, and rewrite it in the same format.
2258 @xref{Target Selection}, for more information.
2261 Show a summary of the options to @command{strip} and exit.
2264 Display a list showing all architectures and object formats available.
2266 @item -I @var{bfdname}
2267 @itemx --input-target=@var{bfdname}
2268 Treat the original @var{objfile} as a file with the object
2269 code format @var{bfdname}.
2270 @xref{Target Selection}, for more information.
2272 @item -O @var{bfdname}
2273 @itemx --output-target=@var{bfdname}
2274 Replace @var{objfile} with a file in the output format @var{bfdname}.
2275 @xref{Target Selection}, for more information.
2277 @item -R @var{sectionname}
2278 @itemx --remove-section=@var{sectionname}
2279 Remove any section named @var{sectionname} from the output file. This
2280 option may be given more than once. Note that using this option
2281 inappropriately may make the output file unusable.
2290 @itemx --strip-debug
2291 Remove debugging symbols only.
2293 @item --strip-unneeded
2294 Remove all symbols that are not needed for relocation processing.
2296 @item -K @var{symbolname}
2297 @itemx --keep-symbol=@var{symbolname}
2298 When stripping symbols, keep symbol @var{symbolname} even if it would
2299 normally be stripped. This option may be given more than once.
2301 @item -N @var{symbolname}
2302 @itemx --strip-symbol=@var{symbolname}
2303 Remove symbol @var{symbolname} from the source file. This option may be
2304 given more than once, and may be combined with strip options other than
2308 Put the stripped output in @var{file}, rather than replacing the
2309 existing file. When this argument is used, only one @var{objfile}
2310 argument may be specified.
2313 @itemx --preserve-dates
2314 Preserve the access and modification dates of the file.
2318 Permit regular expressions in @var{symbolname}s used in other command
2319 line options. The question mark (?), asterisk (*), backslash (\) and
2320 square brackets ([]) operators can be used anywhere in the symbol
2321 name. If the first character of the symbol name is the exclamation
2322 point (!) then the sense of the switch is reversed for that symbol.
2329 would cause strip to only keep symbols that start with the letters
2330 ``fo'', but to discard the symbol ``foo''.
2333 @itemx --discard-all
2334 Remove non-global symbols.
2337 @itemx --discard-locals
2338 Remove compiler-generated local symbols.
2339 (These usually start with @samp{L} or @samp{.}.)
2341 @item --keep-file-symbols
2342 When stripping a file, perhaps with @option{--strip-debug} or
2343 @option{--strip-unneeded}, retain any symbols specifying source file names,
2344 which would otherwise get stripped.
2346 @item --only-keep-debug
2347 Strip a file, removing any sections that would be stripped by
2348 @option{--strip-debug} and leaving the debugging sections.
2350 The intention is that this option will be used in conjunction with
2351 @option{--add-gnu-debuglink} to create a two part executable. One a
2352 stripped binary which will occupy less space in RAM and in a
2353 distribution and the second a debugging information file which is only
2354 needed if debugging abilities are required. The suggested procedure
2355 to create these files is as follows:
2358 @item Link the executable as normal. Assuming that is is called
2360 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2361 create a file containing the debugging info.
2362 @item Run @code{objcopy --strip-debug foo} to create a
2363 stripped executable.
2364 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2365 to add a link to the debugging info into the stripped executable.
2368 Note - the choice of @code{.dbg} as an extension for the debug info
2369 file is arbitrary. Also the @code{--only-keep-debug} step is
2370 optional. You could instead do this:
2373 @item Link the executable as normal.
2374 @item Copy @code{foo} to @code{foo.full}
2375 @item Run @code{strip --strip-debug foo}
2376 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2379 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2380 full executable. It does not have to be a file created by the
2381 @option{--only-keep-debug} switch.
2385 Show the version number for @command{strip}.
2389 Verbose output: list all object files modified. In the case of
2390 archives, @samp{strip -v} lists all members of the archive.
2396 @c man begin SEEALSO strip
2397 the Info entries for @file{binutils}.
2401 @node c++filt, addr2line, strip, Top
2405 @cindex demangling C++ symbols
2407 @c man title cxxfilt Demangle C++ and Java symbols.
2410 @c man begin SYNOPSIS cxxfilt
2411 c++filt [@option{-_}|@option{--strip-underscores}]
2412 [@option{-n}|@option{--no-strip-underscores}]
2413 [@option{-p}|@option{--no-params}]
2414 [@option{-t}|@option{--types}]
2415 [@option{-i}|@option{--no-verbose}]
2416 [@option{-s} @var{format}|@option{--format=}@var{format}]
2417 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2421 @c man begin DESCRIPTION cxxfilt
2424 The C++ and Java languages provide function overloading, which means
2425 that you can write many functions with the same name, providing that
2426 each function takes parameters of different types. In order to be
2427 able to distinguish these similarly named functions C++ and Java
2428 encode them into a low-level assembler name which uniquely identifies
2429 each different version. This process is known as @dfn{mangling}. The
2431 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2432 MS-DOS this program is named @command{CXXFILT}.}
2433 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2434 names into user-level names so that they can be read.
2436 Every alphanumeric word (consisting of letters, digits, underscores,
2437 dollars, or periods) seen in the input is a potential mangled name.
2438 If the name decodes into a C++ name, the C++ name replaces the
2439 low-level name in the output, otherwise the original word is output.
2440 In this way you can pass an entire assembler source file, containing
2441 mangled names, through @command{c++filt} and see the same source file
2442 containing demangled names.
2444 You can also use @command{c++filt} to decipher individual symbols by
2445 passing them on the command line:
2448 c++filt @var{symbol}
2451 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2452 names from the standard input instead. All the results are printed on
2453 the standard output. The difference between reading names from the
2454 command line versus reading names from the standard input is that
2455 command line arguments are expected to be just mangled names and no
2456 checking is performed to seperate them from surrounding text. Thus
2463 will work and demangle the name to ``f()'' whereas:
2469 will not work. (Note the extra comma at the end of the mangled
2470 name which makes it invalid). This command however will work:
2473 echo _Z1fv, | c++filt -n
2476 and will display ``f(),'' ie the demangled name followed by a
2477 trailing comma. This behaviour is because when the names are read
2478 from the standard input it is expected that they might be part of an
2479 assembler source file where there might be extra, extraneous
2480 characters trailing after a mangled name. eg:
2483 .type _Z1fv, @@function
2488 @c man begin OPTIONS cxxfilt
2492 @itemx --strip-underscores
2493 On some systems, both the C and C++ compilers put an underscore in front
2494 of every name. For example, the C name @code{foo} gets the low-level
2495 name @code{_foo}. This option removes the initial underscore. Whether
2496 @command{c++filt} removes the underscore by default is target dependent.
2500 Prints demangled names using Java syntax. The default is to use C++
2504 @itemx --no-strip-underscores
2505 Do not remove the initial underscore.
2509 When demangling the name of a function, do not display the types of
2510 the function's parameters.
2514 Attempt to demangle types as well as function names. This is disabled
2515 by default since mangled types are normally only used internally in
2516 the compiler, and they can be confused with non-mangled names. eg
2517 a function called ``a'' treated as a mangled type name would be
2518 demangled to ``signed char''.
2522 Do not include implementation details (if any) in the demangled
2525 @item -s @var{format}
2526 @itemx --format=@var{format}
2527 @command{c++filt} can decode various methods of mangling, used by
2528 different compilers. The argument to this option selects which
2533 Automatic selection based on executable (the default method)
2535 the one used by the @sc{gnu} C++ compiler (g++)
2537 the one used by the Lucid compiler (lcc)
2539 the one specified by the C++ Annotated Reference Manual
2541 the one used by the HP compiler (aCC)
2543 the one used by the EDG compiler
2545 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2547 the one used by the @sc{gnu} Java compiler (gcj)
2549 the one used by the @sc{gnu} Ada compiler (GNAT).
2553 Print a summary of the options to @command{c++filt} and exit.
2556 Print the version number of @command{c++filt} and exit.
2562 @c man begin SEEALSO cxxfilt
2563 the Info entries for @file{binutils}.
2568 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2569 user interface are subject to change in future releases. In particular,
2570 a command-line option may be required in the the future to decode a name
2571 passed as an argument on the command line; in other words,
2574 c++filt @var{symbol}
2578 may in a future release become
2581 c++filt @var{option} @var{symbol}
2589 @cindex address to file name and line number
2591 @c man title addr2line convert addresses into file names and line numbers.
2594 @c man begin SYNOPSIS addr2line
2595 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2596 [@option{-C}|@option{--demangle}[=@var{style}]]
2597 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2598 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2599 [@option{-i}|@option{--inlines}]
2600 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2605 @c man begin DESCRIPTION addr2line
2607 @command{addr2line} translates program addresses into file names and line
2608 numbers. Given an address and an executable, it uses the debugging
2609 information in the executable to figure out which file name and line
2610 number are associated with a given address.
2612 The executable to use is specified with the @option{-e} option. The
2613 default is the file @file{a.out}.
2615 @command{addr2line} has two modes of operation.
2617 In the first, hexadecimal addresses are specified on the command line,
2618 and @command{addr2line} displays the file name and line number for each
2621 In the second, @command{addr2line} reads hexadecimal addresses from
2622 standard input, and prints the file name and line number for each
2623 address on standard output. In this mode, @command{addr2line} may be used
2624 in a pipe to convert dynamically chosen addresses.
2626 The format of the output is @samp{FILENAME:LINENO}. The file name and
2627 line number for each address is printed on a separate line. If the
2628 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2629 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2630 containing the address.
2632 If the file name or function name can not be determined,
2633 @command{addr2line} will print two question marks in their place. If the
2634 line number can not be determined, @command{addr2line} will print 0.
2638 @c man begin OPTIONS addr2line
2640 The long and short forms of options, shown here as alternatives, are
2644 @item -b @var{bfdname}
2645 @itemx --target=@var{bfdname}
2646 @cindex object code format
2647 Specify that the object-code format for the object files is
2651 @itemx --demangle[=@var{style}]
2652 @cindex demangling in objdump
2653 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2654 Besides removing any initial underscore prepended by the system, this
2655 makes C++ function names readable. Different compilers have different
2656 mangling styles. The optional demangling style argument can be used to
2657 choose an appropriate demangling style for your compiler. @xref{c++filt},
2658 for more information on demangling.
2660 @item -e @var{filename}
2661 @itemx --exe=@var{filename}
2662 Specify the name of the executable for which addresses should be
2663 translated. The default file is @file{a.out}.
2667 Display function names as well as file and line number information.
2671 Display only the base of each file name.
2675 If the address belongs to a function that was inlined, the source
2676 information for all enclosing scopes back to the first non-inlined
2677 function will also be printed. For example, if @code{main} inlines
2678 @code{callee1} which inlines @code{callee2}, and address is from
2679 @code{callee2}, the source information for @code{callee1} and @code{main}
2680 will also be printed.
2686 @c man begin SEEALSO addr2line
2687 Info entries for @file{binutils}.
2694 @command{nlmconv} converts a relocatable object file into a NetWare
2698 @command{nlmconv} currently works with @samp{i386} object
2699 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2700 object files in @sc{elf}, or @code{a.out} format@footnote{
2701 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2702 format in the Binary File Descriptor library. It has only been tested
2703 with the above formats.}.
2707 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2708 utilities, since it is only useful for NLM targets.
2711 @c man title nlmconv converts object code into an NLM.
2714 @c man begin SYNOPSIS nlmconv
2715 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2716 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2717 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2718 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2719 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2720 @var{infile} @var{outfile}
2724 @c man begin DESCRIPTION nlmconv
2726 @command{nlmconv} converts the relocatable @samp{i386} object file
2727 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2728 reading @var{headerfile} for NLM header information. For instructions
2729 on writing the NLM command file language used in header files, see the
2730 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2731 Development and Tools Overview}, which is part of the NLM Software
2732 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2733 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2736 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2739 @command{nlmconv} can perform a link step. In other words, you can list
2740 more than one object file for input if you list them in the definitions
2741 file (rather than simply specifying one input file on the command line).
2742 In this case, @command{nlmconv} calls the linker for you.
2746 @c man begin OPTIONS nlmconv
2749 @item -I @var{bfdname}
2750 @itemx --input-target=@var{bfdname}
2751 Object format of the input file. @command{nlmconv} can usually determine
2752 the format of a given file (so no default is necessary).
2753 @xref{Target Selection}, for more information.
2755 @item -O @var{bfdname}
2756 @itemx --output-target=@var{bfdname}
2757 Object format of the output file. @command{nlmconv} infers the output
2758 format based on the input format, e.g. for a @samp{i386} input file the
2759 output format is @samp{nlm32-i386}.
2760 @xref{Target Selection}, for more information.
2762 @item -T @var{headerfile}
2763 @itemx --header-file=@var{headerfile}
2764 Reads @var{headerfile} for NLM header information. For instructions on
2765 writing the NLM command file language used in header files, see@ see the
2766 @samp{linkers} section, of the @cite{NLM Development and Tools
2767 Overview}, which is part of the NLM Software Developer's Kit, available
2772 Displays (on standard error) the linker command line used by @command{nlmconv}.
2774 @item -l @var{linker}
2775 @itemx --linker=@var{linker}
2776 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2781 Prints a usage summary.
2785 Prints the version number for @command{nlmconv}.
2791 @c man begin SEEALSO nlmconv
2792 the Info entries for @file{binutils}.
2799 @command{windres} may be used to manipulate Windows resources.
2802 @emph{Warning:} @command{windres} is not always built as part of the binary
2803 utilities, since it is only useful for Windows targets.
2806 @c man title windres manipulate Windows resources.
2809 @c man begin SYNOPSIS windres
2810 windres [options] [input-file] [output-file]
2814 @c man begin DESCRIPTION windres
2816 @command{windres} reads resources from an input file and copies them into
2817 an output file. Either file may be in one of three formats:
2821 A text format read by the Resource Compiler.
2824 A binary format generated by the Resource Compiler.
2827 A COFF object or executable.
2830 The exact description of these different formats is available in
2831 documentation from Microsoft.
2833 When @command{windres} converts from the @code{rc} format to the @code{res}
2834 format, it is acting like the Windows Resource Compiler. When
2835 @command{windres} converts from the @code{res} format to the @code{coff}
2836 format, it is acting like the Windows @code{CVTRES} program.
2838 When @command{windres} generates an @code{rc} file, the output is similar
2839 but not identical to the format expected for the input. When an input
2840 @code{rc} file refers to an external filename, an output @code{rc} file
2841 will instead include the file contents.
2843 If the input or output format is not specified, @command{windres} will
2844 guess based on the file name, or, for the input file, the file contents.
2845 A file with an extension of @file{.rc} will be treated as an @code{rc}
2846 file, a file with an extension of @file{.res} will be treated as a
2847 @code{res} file, and a file with an extension of @file{.o} or
2848 @file{.exe} will be treated as a @code{coff} file.
2850 If no output file is specified, @command{windres} will print the resources
2851 in @code{rc} format to standard output.
2853 The normal use is for you to write an @code{rc} file, use @command{windres}
2854 to convert it to a COFF object file, and then link the COFF file into
2855 your application. This will make the resources described in the
2856 @code{rc} file available to Windows.
2860 @c man begin OPTIONS windres
2863 @item -i @var{filename}
2864 @itemx --input @var{filename}
2865 The name of the input file. If this option is not used, then
2866 @command{windres} will use the first non-option argument as the input file
2867 name. If there are no non-option arguments, then @command{windres} will
2868 read from standard input. @command{windres} can not read a COFF file from
2871 @item -o @var{filename}
2872 @itemx --output @var{filename}
2873 The name of the output file. If this option is not used, then
2874 @command{windres} will use the first non-option argument, after any used
2875 for the input file name, as the output file name. If there is no
2876 non-option argument, then @command{windres} will write to standard output.
2877 @command{windres} can not write a COFF file to standard output. Note,
2878 for compatability with @command{rc} the option @option{-fo} is also
2879 accepted, but its use is not recommended.
2881 @item -J @var{format}
2882 @itemx --input-format @var{format}
2883 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2884 @samp{coff}. If no input format is specified, @command{windres} will
2885 guess, as described above.
2887 @item -O @var{format}
2888 @itemx --output-format @var{format}
2889 The output format to generate. @var{format} may be @samp{res},
2890 @samp{rc}, or @samp{coff}. If no output format is specified,
2891 @command{windres} will guess, as described above.
2893 @item -F @var{target}
2894 @itemx --target @var{target}
2895 Specify the BFD format to use for a COFF file as input or output. This
2896 is a BFD target name; you can use the @option{--help} option to see a list
2897 of supported targets. Normally @command{windres} will use the default
2898 format, which is the first one listed by the @option{--help} option.
2900 @ref{Target Selection}.
2903 @item --preprocessor @var{program}
2904 When @command{windres} reads an @code{rc} file, it runs it through the C
2905 preprocessor first. This option may be used to specify the preprocessor
2906 to use, including any leading arguments. The default preprocessor
2907 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2909 @item -I @var{directory}
2910 @itemx --include-dir @var{directory}
2911 Specify an include directory to use when reading an @code{rc} file.
2912 @command{windres} will pass this to the preprocessor as an @option{-I}
2913 option. @command{windres} will also search this directory when looking for
2914 files named in the @code{rc} file. If the argument passed to this command
2915 matches any of the supported @var{formats} (as descrived in the @option{-J}
2916 option), it will issue a deprecation warning, and behave just like the
2917 @option{-J} option. New programs should not use this behaviour. If a
2918 directory happens to match a @var{format}, simple prefix it with @samp{./}
2919 to disable the backward compatibility.
2921 @item -D @var{target}
2922 @itemx --define @var{sym}[=@var{val}]
2923 Specify a @option{-D} option to pass to the preprocessor when reading an
2926 @item -U @var{target}
2927 @itemx --undefine @var{sym}
2928 Specify a @option{-U} option to pass to the preprocessor when reading an
2932 Ignored for compatibility with rc.
2935 Enable verbose mode. This tells you what the preprocessor is if you
2939 @item --language @var{val}
2940 Specify the default language to use when reading an @code{rc} file.
2941 @var{val} should be a hexadecimal language code. The low eight bits are
2942 the language, and the high eight bits are the sublanguage.
2944 @item --use-temp-file
2945 Use a temporary file to instead of using popen to read the output of
2946 the preprocessor. Use this option if the popen implementation is buggy
2947 on the host (eg., certain non-English language versions of Windows 95 and
2948 Windows 98 are known to have buggy popen where the output will instead
2951 @item --no-use-temp-file
2952 Use popen, not a temporary file, to read the output of the preprocessor.
2953 This is the default behaviour.
2957 Prints a usage summary.
2961 Prints the version number for @command{windres}.
2964 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2965 this will turn on parser debugging.
2971 @c man begin SEEALSO windres
2972 the Info entries for @file{binutils}.
2981 @command{dlltool} is used to create the files needed to create dynamic
2982 link libraries (DLLs) on systems which understand PE format image
2983 files such as Windows. A DLL contains an export table which contains
2984 information that the runtime loader needs to resolve references from a
2985 referencing program.
2987 The export table is generated by this program by reading in a
2988 @file{.def} file or scanning the @file{.a} and @file{.o} files which
2989 will be in the DLL. A @file{.o} file can contain information in
2990 special @samp{.drectve} sections with export information.
2993 @emph{Note:} @command{dlltool} is not always built as part of the
2994 binary utilities, since it is only useful for those targets which
2998 @c man title dlltool Create files needed to build and use DLLs.
3001 @c man begin SYNOPSIS dlltool
3002 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3003 [@option{-b}|@option{--base-file} @var{base-file-name}]
3004 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3005 [@option{-z}|@option{--output-def} @var{def-file-name}]
3006 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3007 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3008 [@option{--exclude-symbols} @var{list}]
3009 [@option{--no-default-excludes}]
3010 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3011 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3012 [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{-k}|@option{--kill-at}]
3013 [@option{-A}|@option{--add-stdcall-alias}]
3014 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3015 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
3016 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3017 [@option{-v}|@option{--verbose}]
3018 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3019 [object-file @dots{}]
3023 @c man begin DESCRIPTION dlltool
3025 @command{dlltool} reads its inputs, which can come from the @option{-d} and
3026 @option{-b} options as well as object files specified on the command
3027 line. It then processes these inputs and if the @option{-e} option has
3028 been specified it creates a exports file. If the @option{-l} option
3029 has been specified it creates a library file and if the @option{-z} option
3030 has been specified it creates a def file. Any or all of the @option{-e},
3031 @option{-l} and @option{-z} options can be present in one invocation of
3034 When creating a DLL, along with the source for the DLL, it is necessary
3035 to have three other files. @command{dlltool} can help with the creation of
3038 The first file is a @file{.def} file which specifies which functions are
3039 exported from the DLL, which functions the DLL imports, and so on. This
3040 is a text file and can be created by hand, or @command{dlltool} can be used
3041 to create it using the @option{-z} option. In this case @command{dlltool}
3042 will scan the object files specified on its command line looking for
3043 those functions which have been specially marked as being exported and
3044 put entries for them in the @file{.def} file it creates.
3046 In order to mark a function as being exported from a DLL, it needs to
3047 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
3048 section of the object file. This can be done in C by using the
3052 asm (".section .drectve");
3053 asm (".ascii \"-export:my_func\"");
3055 int my_func (void) @{ @dots{} @}
3058 The second file needed for DLL creation is an exports file. This file
3059 is linked with the object files that make up the body of the DLL and it
3060 handles the interface between the DLL and the outside world. This is a
3061 binary file and it can be created by giving the @option{-e} option to
3062 @command{dlltool} when it is creating or reading in a @file{.def} file.
3064 The third file needed for DLL creation is the library file that programs
3065 will link with in order to access the functions in the DLL. This file
3066 can be created by giving the @option{-l} option to dlltool when it
3067 is creating or reading in a @file{.def} file.
3069 @command{dlltool} builds the library file by hand, but it builds the
3070 exports file by creating temporary files containing assembler statements
3071 and then assembling these. The @option{-S} command line option can be
3072 used to specify the path to the assembler that dlltool will use,
3073 and the @option{-f} option can be used to pass specific flags to that
3074 assembler. The @option{-n} can be used to prevent dlltool from deleting
3075 these temporary assembler files when it is done, and if @option{-n} is
3076 specified twice then this will prevent dlltool from deleting the
3077 temporary object files it used to build the library.
3079 Here is an example of creating a DLL from a source file @samp{dll.c} and
3080 also creating a program (from an object file called @samp{program.o})
3085 dlltool -e exports.o -l dll.lib dll.o
3086 gcc dll.o exports.o -o dll.dll
3087 gcc program.o dll.lib -o program
3092 @c man begin OPTIONS dlltool
3094 The command line options have the following meanings:
3098 @item -d @var{filename}
3099 @itemx --input-def @var{filename}
3100 @cindex input .def file
3101 Specifies the name of a @file{.def} file to be read in and processed.
3103 @item -b @var{filename}
3104 @itemx --base-file @var{filename}
3106 Specifies the name of a base file to be read in and processed. The
3107 contents of this file will be added to the relocation section in the
3108 exports file generated by dlltool.
3110 @item -e @var{filename}
3111 @itemx --output-exp @var{filename}
3112 Specifies the name of the export file to be created by dlltool.
3114 @item -z @var{filename}
3115 @itemx --output-def @var{filename}
3116 Specifies the name of the @file{.def} file to be created by dlltool.
3118 @item -l @var{filename}
3119 @itemx --output-lib @var{filename}
3120 Specifies the name of the library file to be created by dlltool.
3122 @item --export-all-symbols
3123 Treat all global and weak defined symbols found in the input object
3124 files as symbols to be exported. There is a small list of symbols which
3125 are not exported by default; see the @option{--no-default-excludes}
3126 option. You may add to the list of symbols to not export by using the
3127 @option{--exclude-symbols} option.
3129 @item --no-export-all-symbols
3130 Only export symbols explicitly listed in an input @file{.def} file or in
3131 @samp{.drectve} sections in the input object files. This is the default
3132 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3133 attributes in the source code.
3135 @item --exclude-symbols @var{list}
3136 Do not export the symbols in @var{list}. This is a list of symbol names
3137 separated by comma or colon characters. The symbol names should not
3138 contain a leading underscore. This is only meaningful when
3139 @option{--export-all-symbols} is used.
3141 @item --no-default-excludes
3142 When @option{--export-all-symbols} is used, it will by default avoid
3143 exporting certain special symbols. The current list of symbols to avoid
3144 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3145 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3146 to go ahead and export these special symbols. This is only meaningful
3147 when @option{--export-all-symbols} is used.
3150 @itemx --as @var{path}
3151 Specifies the path, including the filename, of the assembler to be used
3152 to create the exports file.
3154 @item -f @var{options}
3155 @itemx --as-flags @var{options}
3156 Specifies any specific command line options to be passed to the
3157 assembler when building the exports file. This option will work even if
3158 the @option{-S} option is not used. This option only takes one argument,
3159 and if it occurs more than once on the command line, then later
3160 occurrences will override earlier occurrences. So if it is necessary to
3161 pass multiple options to the assembler they should be enclosed in
3165 @itemx --dll-name @var{name}
3166 Specifies the name to be stored in the @file{.def} file as the name of
3167 the DLL when the @option{-e} option is used. If this option is not
3168 present, then the filename given to the @option{-e} option will be
3169 used as the name of the DLL.
3171 @item -m @var{machine}
3172 @itemx -machine @var{machine}
3173 Specifies the type of machine for which the library file should be
3174 built. @command{dlltool} has a built in default type, depending upon how
3175 it was created, but this option can be used to override that. This is
3176 normally only useful when creating DLLs for an ARM processor, when the
3177 contents of the DLL are actually encode using Thumb instructions.
3180 @itemx --add-indirect
3181 Specifies that when @command{dlltool} is creating the exports file it
3182 should add a section which allows the exported functions to be
3183 referenced without using the import library. Whatever the hell that
3187 @itemx --add-underscore
3188 Specifies that when @command{dlltool} is creating the exports file it
3189 should prepend an underscore to the names of the exported functions.
3193 Specifies that when @command{dlltool} is creating the exports file it
3194 should not append the string @samp{@@ <number>}. These numbers are
3195 called ordinal numbers and they represent another way of accessing the
3196 function in a DLL, other than by name.
3199 @itemx --add-stdcall-alias
3200 Specifies that when @command{dlltool} is creating the exports file it
3201 should add aliases for stdcall symbols without @samp{@@ <number>}
3202 in addition to the symbols with @samp{@@ <number>}.
3205 @itemx --ext-prefix-alias @var{prefix}
3206 Causes @command{dlltool} to create external aliases for all DLL
3207 imports with the specified prefix. The aliases are created for both
3208 external and import symbols with no leading underscore.
3212 Specifies that when @command{dlltool} is creating the exports and library
3213 files it should omit the @code{.idata4} section. This is for compatibility
3214 with certain operating systems.
3218 Specifies that when @command{dlltool} is creating the exports and library
3219 files it should omit the @code{.idata5} section. This is for compatibility
3220 with certain operating systems.
3224 Specifies that @command{dlltool} should mark the objects in the library
3225 file and exports file that it produces as supporting interworking
3226 between ARM and Thumb code.
3230 Makes @command{dlltool} preserve the temporary assembler files it used to
3231 create the exports file. If this option is repeated then dlltool will
3232 also preserve the temporary object files it uses to create the library
3235 @item -t @var{prefix}
3236 @itemx --temp-prefix @var{prefix}
3237 Makes @command{dlltool} use @var{prefix} when constructing the names of
3238 temporary assembler and object files. By default, the temp file prefix
3239 is generated from the pid.
3243 Make dlltool describe what it is doing.
3247 Displays a list of command line options and then exits.
3251 Displays dlltool's version number and then exits.
3258 * def file format:: The format of the dlltool @file{.def} file
3261 @node def file format
3262 @section The format of the @command{dlltool} @file{.def} file
3264 A @file{.def} file contains any number of the following commands:
3268 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
3269 The result is going to be named @var{name}@code{.exe}.
3271 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
3272 The result is going to be named @var{name}@code{.dll}.
3274 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )}
3275 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
3276 Declares @var{name1} as an exported symbol from the DLL, with optional
3277 ordinal number @var{integer}, or declares @var{name1} as an alias
3278 (forward) of the function @var{external-name} in the DLL
3281 @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{) ) *}
3282 Declares that @var{external-name} or the exported function whose
3283 ordinal number is @var{integer} is to be imported from the file
3284 @var{module-name}. If @var{internal-name} is specified then this is
3285 the name that the imported function will be referred to in the body of
3288 @item @code{DESCRIPTION} @var{string}
3289 Puts @var{string} into the output @file{.exp} file in the
3290 @code{.rdata} section.
3292 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3293 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3294 Generates @code{--stack} or @code{--heap}
3295 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
3296 section. The linker will see this and act upon it.
3298 @item @code{CODE} @var{attr} @code{+}
3299 @item @code{DATA} @var{attr} @code{+}
3300 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
3301 Generates @code{--attr} @var{section-name} @var{attr} in the output
3302 @code{.drectve} section, where @var{attr} is one of @code{READ},
3303 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
3304 this and act upon it.
3309 @c man begin SEEALSO dlltool
3310 The Info pages for @file{binutils}.
3317 @cindex ELF file information
3320 @c man title readelf Displays information about ELF files.
3323 @c man begin SYNOPSIS readelf
3324 readelf [@option{-a}|@option{--all}]
3325 [@option{-h}|@option{--file-header}]
3326 [@option{-l}|@option{--program-headers}|@option{--segments}]
3327 [@option{-S}|@option{--section-headers}|@option{--sections}]
3328 [@option{-g}|@option{--section-groups}]
3329 [@option{-t}|@option{--section-details}]
3330 [@option{-e}|@option{--headers}]
3331 [@option{-s}|@option{--syms}|@option{--symbols}]
3332 [@option{-n}|@option{--notes}]
3333 [@option{-r}|@option{--relocs}]
3334 [@option{-u}|@option{--unwind}]
3335 [@option{-d}|@option{--dynamic}]
3336 [@option{-V}|@option{--version-info}]
3337 [@option{-A}|@option{--arch-specific}]
3338 [@option{-D}|@option{--use-dynamic}]
3339 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
3340 [@option{-w[liaprmfFsoR]}|
3341 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
3342 [@option{-I}|@option{-histogram}]
3343 [@option{-v}|@option{--version}]
3344 [@option{-W}|@option{--wide}]
3345 [@option{-H}|@option{--help}]
3346 @var{elffile}@dots{}
3350 @c man begin DESCRIPTION readelf
3352 @command{readelf} displays information about one or more ELF format object
3353 files. The options control what particular information to display.
3355 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3356 64-bit ELF files are supported, as are archives containing ELF files.
3358 This program performs a similar function to @command{objdump} but it
3359 goes into more detail and it exists independently of the @sc{bfd}
3360 library, so if there is a bug in @sc{bfd} then readelf will not be
3365 @c man begin OPTIONS readelf
3367 The long and short forms of options, shown here as alternatives, are
3368 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3374 Equivalent to specifiying @option{--file-header},
3375 @option{--program-headers}, @option{--sections}, @option{--symbols},
3376 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3377 @option{--version-info}.
3380 @itemx --file-header
3381 @cindex ELF file header information
3382 Displays the information contained in the ELF header at the start of the
3386 @itemx --program-headers
3388 @cindex ELF program header information
3389 @cindex ELF segment information
3390 Displays the information contained in the file's segment headers, if it
3395 @itemx --section-headers
3396 @cindex ELF section information
3397 Displays the information contained in the file's section headers, if it
3401 @itemx --section-groups
3402 @cindex ELF section group information
3403 Displays the information contained in the file's section groups, if it
3407 @itemx --section-details
3408 @cindex ELF section information
3409 Displays the detailed section information. Implies @option{-S}.
3414 @cindex ELF symbol table information
3415 Displays the entries in symbol table section of the file, if it has one.
3419 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3424 Displays the contents of the NOTE segments and/or sections, if any.
3428 @cindex ELF reloc information
3429 Displays the contents of the file's relocation section, if it has one.
3433 @cindex unwind information
3434 Displays the contents of the file's unwind section, if it has one. Only
3435 the unwind sections for IA64 ELF files are currently supported.
3439 @cindex ELF dynamic section information
3440 Displays the contents of the file's dynamic section, if it has one.
3443 @itemx --version-info
3444 @cindex ELF version sections informations
3445 Displays the contents of the version sections in the file, it they
3449 @itemx --arch-specific
3450 Displays architecture-specific information in the file, if there
3454 @itemx --use-dynamic
3455 When displaying symbols, this option makes @command{readelf} use the
3456 symbol table in the file's dynamic section, rather than the one in the
3459 @item -x <number or name>
3460 @itemx --hex-dump=<number or name>
3461 Displays the contents of the indicated section as a hexadecimal dump.
3462 A number identifies a particular section by index in the section table;
3463 any other string identifies all sections with that name in the object file.
3465 @item -w[liaprmfFsoR]
3466 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
3467 Displays the contents of the debug sections in the file, if any are
3468 present. If one of the optional letters or words follows the switch
3469 then only data found in those specific sections will be dumped.
3473 Display a histogram of bucket list lengths when displaying the contents
3474 of the symbol tables.
3478 Display the version number of readelf.
3482 Don't break output lines to fit into 80 columns. By default
3483 @command{readelf} breaks section header and segment listing lines for
3484 64-bit ELF files, so that they fit into 80 columns. This option causes
3485 @command{readelf} to print each section header resp. each segment one a
3486 single line, which is far more readable on terminals wider than 80 columns.
3490 Display the command line options understood by @command{readelf}.
3497 @c man begin SEEALSO readelf
3498 objdump(1), and the Info entries for @file{binutils}.
3502 @node Common Options
3503 @chapter Common Options
3505 The following command-line options are supported by all of the
3506 programs described in this manual.
3509 @include @value{top_srcdir}/../libiberty/at-file.texi
3512 Display the command-line options supported by the program.
3515 Display the version number of the program.
3519 @node Selecting The Target System
3520 @chapter Selecting the Target System
3522 You can specify two aspects of the target system to the @sc{gnu}
3523 binary file utilities, each in several ways:
3533 In the following summaries, the lists of ways to specify values are in
3534 order of decreasing precedence. The ways listed first override those
3537 The commands to list valid values only list the values for which the
3538 programs you are running were configured. If they were configured with
3539 @option{--enable-targets=all}, the commands list most of the available
3540 values, but a few are left out; not all targets can be configured in at
3541 once because some of them can only be configured @dfn{native} (on hosts
3542 with the same type as the target system).
3545 * Target Selection::
3546 * Architecture Selection::
3549 @node Target Selection
3550 @section Target Selection
3552 A @dfn{target} is an object file format. A given target may be
3553 supported for multiple architectures (@pxref{Architecture Selection}).
3554 A target selection may also have variations for different operating
3555 systems or architectures.
3557 The command to list valid target values is @samp{objdump -i}
3558 (the first column of output contains the relevant information).
3560 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3561 @samp{a.out-sunos-big}.
3563 You can also specify a target using a configuration triplet. This is
3564 the same sort of name that is passed to @file{configure} to specify a
3565 target. When you use a configuration triplet as an argument, it must be
3566 fully canonicalized. You can see the canonical version of a triplet by
3567 running the shell script @file{config.sub} which is included with the
3570 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3571 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3573 @subheading @command{objdump} Target
3579 command line option: @option{-b} or @option{--target}
3582 environment variable @code{GNUTARGET}
3585 deduced from the input file
3588 @subheading @command{objcopy} and @command{strip} Input Target
3594 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3597 environment variable @code{GNUTARGET}
3600 deduced from the input file
3603 @subheading @command{objcopy} and @command{strip} Output Target
3609 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3612 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3615 environment variable @code{GNUTARGET}
3618 deduced from the input file
3621 @subheading @command{nm}, @command{size}, and @command{strings} Target
3627 command line option: @option{--target}
3630 environment variable @code{GNUTARGET}
3633 deduced from the input file
3636 @node Architecture Selection
3637 @section Architecture Selection
3639 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3640 to run. Its name may contain a colon, separating the name of the
3641 processor family from the name of the particular @sc{cpu}.
3643 The command to list valid architecture values is @samp{objdump -i} (the
3644 second column contains the relevant information).
3646 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3648 @subheading @command{objdump} Architecture
3654 command line option: @option{-m} or @option{--architecture}
3657 deduced from the input file
3660 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3666 deduced from the input file
3669 @node Reporting Bugs
3670 @chapter Reporting Bugs
3672 @cindex reporting bugs
3674 Your bug reports play an essential role in making the binary utilities
3677 Reporting a bug may help you by bringing a solution to your problem, or
3678 it may not. But in any case the principal function of a bug report is
3679 to help the entire community by making the next version of the binary
3680 utilities work better. Bug reports are your contribution to their
3683 In order for a bug report to serve its purpose, you must include the
3684 information that enables us to fix the bug.
3687 * Bug Criteria:: Have you found a bug?
3688 * Bug Reporting:: How to report bugs
3692 @section Have You Found a Bug?
3693 @cindex bug criteria
3695 If you are not sure whether you have found a bug, here are some guidelines:
3698 @cindex fatal signal
3701 If a binary utility gets a fatal signal, for any input whatever, that is
3702 a bug. Reliable utilities never crash.
3704 @cindex error on valid input
3706 If a binary utility produces an error message for valid input, that is a
3710 If you are an experienced user of binary utilities, your suggestions for
3711 improvement are welcome in any case.
3715 @section How to Report Bugs
3717 @cindex bugs, reporting
3719 A number of companies and individuals offer support for @sc{gnu}
3720 products. If you obtained the binary utilities from a support
3721 organization, we recommend you contact that organization first.
3723 You can find contact information for many support companies and
3724 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3727 In any event, we also recommend that you send bug reports for the binary
3728 utilities to @samp{bug-binutils@@gnu.org}.
3730 The fundamental principle of reporting bugs usefully is this:
3731 @strong{report all the facts}. If you are not sure whether to state a
3732 fact or leave it out, state it!
3734 Often people omit facts because they think they know what causes the
3735 problem and assume that some details do not matter. Thus, you might
3736 assume that the name of a file you use in an example does not matter.
3737 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3738 a stray memory reference which happens to fetch from the location where
3739 that pathname is stored in memory; perhaps, if the pathname were
3740 different, the contents of that location would fool the utility into
3741 doing the right thing despite the bug. Play it safe and give a
3742 specific, complete example. That is the easiest thing for you to do,
3743 and the most helpful.
3745 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3746 it is new to us. Therefore, always write your bug reports on the assumption
3747 that the bug has not been reported previously.
3749 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3750 bell?'' This cannot help us fix a bug, so it is basically useless. We
3751 respond by asking for enough details to enable us to investigate.
3752 You might as well expedite matters by sending them to begin with.
3754 To enable us to fix the bug, you should include all these things:
3758 The version of the utility. Each utility announces it if you start it
3759 with the @option{--version} argument.
3761 Without this, we will not know whether there is any point in looking for
3762 the bug in the current version of the binary utilities.
3765 Any patches you may have applied to the source, including any patches
3766 made to the @code{BFD} library.
3769 The type of machine you are using, and the operating system name and
3773 What compiler (and its version) was used to compile the utilities---e.g.
3777 The command arguments you gave the utility to observe the bug. To
3778 guarantee you will not omit something important, list them all. A copy
3779 of the Makefile (or the output from make) is sufficient.
3781 If we were to try to guess the arguments, we would probably guess wrong
3782 and then we might not encounter the bug.
3785 A complete input file, or set of input files, that will reproduce the
3786 bug. If the utility is reading an object file or files, then it is
3787 generally most helpful to send the actual object files, uuencoded if
3788 necessary to get them through the mail system. Note that
3789 @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid
3790 sending very large files to it. Making the files available for
3791 anonymous FTP is OK.
3793 If the source files were produced exclusively using @sc{gnu} programs
3794 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3795 may be OK to send the source files rather than the object files. In
3796 this case, be sure to say exactly what version of @command{gcc}, or
3797 whatever, was used to produce the object files. Also say how
3798 @command{gcc}, or whatever, was configured.
3801 A description of what behavior you observe that you believe is
3802 incorrect. For example, ``It gets a fatal signal.''
3804 Of course, if the bug is that the utility gets a fatal signal, then we
3805 will certainly notice it. But if the bug is incorrect output, we might
3806 not notice unless it is glaringly wrong. You might as well not give us
3807 a chance to make a mistake.
3809 Even if the problem you experience is a fatal signal, you should still
3810 say so explicitly. Suppose something strange is going on, such as your
3811 copy of the utility is out of synch, or you have encountered a bug in
3812 the C library on your system. (This has happened!) Your copy might
3813 crash and ours would not. If you told us to expect a crash, then when
3814 ours fails to crash, we would know that the bug was not happening for
3815 us. If you had not told us to expect a crash, then we would not be able
3816 to draw any conclusion from our observations.
3819 If you wish to suggest changes to the source, send us context diffs, as
3820 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3821 option. Always send diffs from the old file to the new file. If you
3822 wish to discuss something in the @command{ld} source, refer to it by
3823 context, not by line number.
3825 The line numbers in our development sources will not match those in your
3826 sources. Your line numbers would convey no useful information to us.
3829 Here are some things that are not necessary:
3833 A description of the envelope of the bug.
3835 Often people who encounter a bug spend a lot of time investigating
3836 which changes to the input file will make the bug go away and which
3837 changes will not affect it.
3839 This is often time consuming and not very useful, because the way we
3840 will find the bug is by running a single example under the debugger
3841 with breakpoints, not by pure deduction from a series of examples.
3842 We recommend that you save your time for something else.
3844 Of course, if you can find a simpler example to report @emph{instead}
3845 of the original one, that is a convenience for us. Errors in the
3846 output will be easier to spot, running under the debugger will take
3847 less time, and so on.
3849 However, simplification is not vital; if you do not want to do this,
3850 report the bug anyway and send us the entire test case you used.
3853 A patch for the bug.
3855 A patch for the bug does help us if it is a good one. But do not omit
3856 the necessary information, such as the test case, on the assumption that
3857 a patch is all we need. We might see problems with your patch and decide
3858 to fix the problem another way, or we might not understand it at all.
3860 Sometimes with programs as complicated as the binary utilities it is
3861 very hard to construct an example that will make the program follow a
3862 certain path through the code. If you do not send us the example, we
3863 will not be able to construct one, so we will not be able to verify that
3866 And if we cannot understand what bug you are trying to fix, or why your
3867 patch should be an improvement, we will not install it. A test case will
3868 help us to understand.
3871 A guess about what the bug is or what it depends on.
3873 Such guesses are usually wrong. Even we cannot guess right about such
3874 things without first using the debugger to find the facts.