1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 @c Free Software Foundation, Inc.
13 * Binutils: (binutils). The GNU binary utilities.
14 * ar: (binutils)ar. Create, modify, and extract from archives
15 * nm: (binutils)nm. List symbols from object files
16 * objcopy: (binutils)objcopy. Copy and translate object files
17 * objdump: (binutils)objdump. Display information from object files
18 * ranlib: (binutils)ranlib. Generate index to archive contents
19 * readelf: (binutils)readelf. Display the contents of ELF format files.
20 * size: (binutils)size. List section sizes and total size
21 * strings: (binutils)strings. List printable strings from files
22 * strip: (binutils)strip. Discard symbols
23 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
24 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
25 * addr2line: (binutils)addr2line. Convert addresses to file and line
26 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
27 * windres: (binutils)windres. Manipulate Windows resources
28 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
34 @c man begin COPYRIGHT
35 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
36 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
38 Permission is granted to copy, distribute and/or modify this document
39 under the terms of the GNU Free Documentation License, Version 1.1
40 or any later version published by the Free Software Foundation;
41 with no Invariant Sections, with no Front-Cover Texts, and with no
42 Back-Cover Texts. A copy of the license is included in the
43 section entitled ``GNU Free Documentation License''.
47 Permission is granted to process this file through TeX and print the
48 results, provided the printed document carries a copying permission
49 notice identical to this one except for the removal of this paragraph
50 (this paragraph not being relevant to the printed manual).
57 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
58 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
60 @c Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
61 @c 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
63 @c This text may be freely distributed under the terms of the GNU
64 @c Free Documentation License.
67 @setchapternewpage odd
68 @settitle @sc{gnu} Binary Utilities
71 @title The @sc{gnu} Binary Utilities
72 @ifset VERSION_PACKAGE
73 @subtitle @value{VERSION_PACKAGE}
75 @subtitle Version @value{VERSION}
77 @subtitle @value{UPDATED}
78 @author Roland H. Pesch
79 @author Jeffrey M. Osier
80 @author Cygnus Support
84 {\parskip=0pt \hfill Cygnus Support\par \hfill
85 \TeX{}info \texinfoversion\par }
88 @vskip 0pt plus 1filll
89 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
90 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
92 Permission is granted to copy, distribute and/or modify this document
93 under the terms of the GNU Free Documentation License, Version 1.1
94 or any later version published by the Free Software Foundation;
95 with no Invariant Sections, with no Front-Cover Texts, and with no
96 Back-Cover Texts. A copy of the license is included in the
97 section entitled ``GNU Free Documentation License''.
106 This brief manual contains documentation for the @sc{gnu} binary
108 @ifset VERSION_PACKAGE
109 @value{VERSION_PACKAGE}
111 version @value{VERSION}:
116 Create, modify, and extract from archives
119 List symbols from object files
122 Copy and translate object files
125 Display information from object files
128 Generate index to archive contents
131 Display the contents of ELF format files.
134 List file section sizes and total size
137 List printable strings from files
143 Demangle encoded C++ symbols (on MS-DOS, this program is named
147 Convert addresses into file names and line numbers
150 Convert object code into a Netware Loadable Module
153 Manipulate Windows resources
156 Create the files needed to build and use Dynamic Link Libraries
160 This document is distributed under the terms of the GNU Free
161 Documentation License. A copy of the license is included in the
162 section entitled "GNU Free Documentation License".
165 * ar:: Create, modify, and extract from archives
166 * nm:: List symbols from object files
167 * objcopy:: Copy and translate object files
168 * objdump:: Display information from object files
169 * ranlib:: Generate index to archive contents
170 * readelf:: Display the contents of ELF format files.
171 * size:: List section sizes and total size
172 * strings:: List printable strings from files
173 * strip:: Discard symbols
174 * c++filt:: Filter to demangle encoded C++ symbols
175 * cxxfilt: c++filt. MS-DOS name for c++filt
176 * addr2line:: Convert addresses to file and line
177 * nlmconv:: Converts object code into an NLM
178 * windres:: Manipulate Windows resources
179 * dlltool:: Create files needed to build and use DLLs
180 * Common Options:: Command-line options for all utilities
181 * Selecting The Target System:: How these utilities determine the target.
182 * Reporting Bugs:: Reporting Bugs
183 * GNU Free Documentation License:: GNU Free Documentation License
184 * Binutils Index:: Binutils Index
192 @cindex collections of files
194 @c man title ar create, modify, and extract from archives
197 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
198 ar -M [ <mri-script ]
201 @c man begin DESCRIPTION ar
203 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
204 archives. An @dfn{archive} is a single file holding a collection of
205 other files in a structure that makes it possible to retrieve
206 the original individual files (called @dfn{members} of the archive).
208 The original files' contents, mode (permissions), timestamp, owner, and
209 group are preserved in the archive, and can be restored on
213 @sc{gnu} @command{ar} can maintain archives whose members have names of any
214 length; however, depending on how @command{ar} is configured on your
215 system, a limit on member-name length may be imposed for compatibility
216 with archive formats maintained with other tools. If it exists, the
217 limit is often 15 characters (typical of formats related to a.out) or 16
218 characters (typical of formats related to coff).
221 @command{ar} is considered a binary utility because archives of this sort
222 are most often used as @dfn{libraries} holding commonly needed
226 @command{ar} creates an index to the symbols defined in relocatable
227 object modules in the archive when you specify the modifier @samp{s}.
228 Once created, this index is updated in the archive whenever @command{ar}
229 makes a change to its contents (save for the @samp{q} update operation).
230 An archive with such an index speeds up linking to the library, and
231 allows routines in the library to call each other without regard to
232 their placement in the archive.
234 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
235 table. If an archive lacks the table, another form of @command{ar} called
236 @command{ranlib} can be used to add just the table.
238 @cindex compatibility, @command{ar}
239 @cindex @command{ar} compatibility
240 @sc{gnu} @command{ar} is designed to be compatible with two different
241 facilities. You can control its activity using command-line options,
242 like the different varieties of @command{ar} on Unix systems; or, if you
243 specify the single command-line option @option{-M}, you can control it
244 with a script supplied via standard input, like the MRI ``librarian''
250 * ar cmdline:: Controlling @command{ar} on the command line
251 * ar scripts:: Controlling @command{ar} with a script
256 @section Controlling @command{ar} on the Command Line
259 @c man begin SYNOPSIS ar
260 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
264 @cindex Unix compatibility, @command{ar}
265 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
266 arguments to execute: one keyletter specifying the @emph{operation}
267 (optionally accompanied by other keyletters specifying
268 @emph{modifiers}), and the archive name to act on.
270 Most operations can also accept further @var{member} arguments,
271 specifying particular files to operate on.
273 @c man begin OPTIONS ar
275 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
276 flags @var{mod} in any order, within the first command-line argument.
278 If you wish, you may begin the first command-line argument with a
281 @cindex operations on archive
282 The @var{p} keyletter specifies what operation to execute; it may be
283 any of the following, but you must specify only one of them:
287 @cindex deleting from archive
288 @emph{Delete} modules from the archive. Specify the names of modules to
289 be deleted as @var{member}@dots{}; the archive is untouched if you
290 specify no files to delete.
292 If you specify the @samp{v} modifier, @command{ar} lists each module
296 @cindex moving in archive
297 Use this operation to @emph{move} members in an archive.
299 The ordering of members in an archive can make a difference in how
300 programs are linked using the library, if a symbol is defined in more
303 If no modifiers are used with @code{m}, any members you name in the
304 @var{member} arguments are moved to the @emph{end} of the archive;
305 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
306 specified place instead.
309 @cindex printing from archive
310 @emph{Print} the specified members of the archive, to the standard
311 output file. If the @samp{v} modifier is specified, show the member
312 name before copying its contents to standard output.
314 If you specify no @var{member} arguments, all the files in the archive are
318 @cindex quick append to archive
319 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
320 @var{archive}, without checking for replacement.
322 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
323 operation; new members are always placed at the end of the archive.
325 The modifier @samp{v} makes @command{ar} list each file as it is appended.
327 Since the point of this operation is speed, the archive's symbol table
328 index is not updated, even if it already existed; you can use @samp{ar s} or
329 @command{ranlib} explicitly to update the symbol table index.
331 However, too many different systems assume quick append rebuilds the
332 index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
335 @cindex replacement in archive
336 Insert the files @var{member}@dots{} into @var{archive} (with
337 @emph{replacement}). This operation differs from @samp{q} in that any
338 previously existing members are deleted if their names match those being
341 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
342 displays an error message, and leaves undisturbed any existing members
343 of the archive matching that name.
345 By default, new members are added at the end of the file; but you may
346 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
347 placement relative to some existing member.
349 The modifier @samp{v} used with this operation elicits a line of
350 output for each file inserted, along with one of the letters @samp{a} or
351 @samp{r} to indicate whether the file was appended (no old member
352 deleted) or replaced.
355 @cindex contents of archive
356 Display a @emph{table} listing the contents of @var{archive}, or those
357 of the files listed in @var{member}@dots{} that are present in the
358 archive. Normally only the member name is shown; if you also want to
359 see the modes (permissions), timestamp, owner, group, and size, you can
360 request that by also specifying the @samp{v} modifier.
362 If you do not specify a @var{member}, all files in the archive
365 @cindex repeated names in archive
366 @cindex name duplication in archive
367 If there is more than one file with the same name (say, @samp{fie}) in
368 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
369 first instance; to see them all, you must ask for a complete
370 listing---in our example, @samp{ar t b.a}.
371 @c WRS only; per Gumby, this is implementation-dependent, and in a more
372 @c recent case in fact works the other way.
375 @cindex extract from archive
376 @emph{Extract} members (named @var{member}) from the archive. You can
377 use the @samp{v} modifier with this operation, to request that
378 @command{ar} list each name as it extracts it.
380 If you do not specify a @var{member}, all files in the archive
385 A number of modifiers (@var{mod}) may immediately follow the @var{p}
386 keyletter, to specify variations on an operation's behavior:
390 @cindex relative placement in archive
391 Add new files @emph{after} an existing member of the
392 archive. If you use the modifier @samp{a}, the name of an existing archive
393 member must be present as the @var{relpos} argument, before the
394 @var{archive} specification.
397 Add new files @emph{before} an existing member of the
398 archive. If you use the modifier @samp{b}, the name of an existing archive
399 member must be present as the @var{relpos} argument, before the
400 @var{archive} specification. (same as @samp{i}).
403 @cindex creating archives
404 @emph{Create} the archive. The specified @var{archive} is always
405 created if it did not exist, when you request an update. But a warning is
406 issued unless you specify in advance that you expect to create it, by
410 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
411 names of any length. This will cause it to create archives which are
412 not compatible with the native @command{ar} program on some systems. If
413 this is a concern, the @samp{f} modifier may be used to truncate file
414 names when putting them in the archive.
417 Insert new files @emph{before} an existing member of the
418 archive. If you use the modifier @samp{i}, the name of an existing archive
419 member must be present as the @var{relpos} argument, before the
420 @var{archive} specification. (same as @samp{b}).
423 This modifier is accepted but not used.
424 @c whaffor ar l modifier??? presumably compat; with
425 @c what???---doc@@cygnus.com, 25jan91
428 Uses the @var{count} parameter. This is used if there are multiple
429 entries in the archive with the same name. Extract or delete instance
430 @var{count} of the given name from the archive.
433 @cindex dates in archive
434 Preserve the @emph{original} dates of members when extracting them. If
435 you do not specify this modifier, files extracted from the archive
436 are stamped with the time of extraction.
439 Use the full path name when matching names in the archive. @sc{gnu}
440 @command{ar} can not create an archive with a full path name (such archives
441 are not POSIX complaint), but other archive creators can. This option
442 will cause @sc{gnu} @command{ar} to match file names using a complete path
443 name, which can be convenient when extracting a single file from an
444 archive created by another tool.
447 @cindex writing archive index
448 Write an object-file index into the archive, or update an existing one,
449 even if no other change is made to the archive. You may use this modifier
450 flag either with any operation, or alone. Running @samp{ar s} on an
451 archive is equivalent to running @samp{ranlib} on it.
454 @cindex not writing archive index
455 Do not generate an archive symbol table. This can speed up building a
456 large library in several steps. The resulting archive can not be used
457 with the linker. In order to build a symbol table, you must omit the
458 @samp{S} modifier on the last execution of @samp{ar}, or you must run
459 @samp{ranlib} on the archive.
462 @cindex updating an archive
463 Normally, @samp{ar r}@dots{} inserts all files
464 listed into the archive. If you would like to insert @emph{only} those
465 of the files you list that are newer than existing members of the same
466 names, use this modifier. The @samp{u} modifier is allowed only for the
467 operation @samp{r} (replace). In particular, the combination @samp{qu} is
468 not allowed, since checking the timestamps would lose any speed
469 advantage from the operation @samp{q}.
472 This modifier requests the @emph{verbose} version of an operation. Many
473 operations display additional information, such as filenames processed,
474 when the modifier @samp{v} is appended.
477 This modifier shows the version number of @command{ar}.
480 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
481 compatibility with AIX. The behaviour produced by this option is the
482 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
483 @samp{-X} options; in particular, it does not support @option{-X32}
484 which is the default for AIX @command{ar}.
489 @c man begin SEEALSO ar
490 nm(1), ranlib(1), and the Info entries for @file{binutils}.
495 @section Controlling @command{ar} with a Script
498 ar -M [ <@var{script} ]
501 @cindex MRI compatibility, @command{ar}
502 @cindex scripts, @command{ar}
503 If you use the single command-line option @samp{-M} with @command{ar}, you
504 can control its operation with a rudimentary command language. This
505 form of @command{ar} operates interactively if standard input is coming
506 directly from a terminal. During interactive use, @command{ar} prompts for
507 input (the prompt is @samp{AR >}), and continues executing even after
508 errors. If you redirect standard input to a script file, no prompts are
509 issued, and @command{ar} abandons execution (with a nonzero exit code)
512 The @command{ar} command language is @emph{not} designed to be equivalent
513 to the command-line options; in fact, it provides somewhat less control
514 over archives. The only purpose of the command language is to ease the
515 transition to @sc{gnu} @command{ar} for developers who already have scripts
516 written for the MRI ``librarian'' program.
518 The syntax for the @command{ar} command language is straightforward:
521 commands are recognized in upper or lower case; for example, @code{LIST}
522 is the same as @code{list}. In the following descriptions, commands are
523 shown in upper case for clarity.
526 a single command may appear on each line; it is the first word on the
530 empty lines are allowed, and have no effect.
533 comments are allowed; text after either of the characters @samp{*}
534 or @samp{;} is ignored.
537 Whenever you use a list of names as part of the argument to an @command{ar}
538 command, you can separate the individual names with either commas or
539 blanks. Commas are shown in the explanations below, for clarity.
542 @samp{+} is used as a line continuation character; if @samp{+} appears
543 at the end of a line, the text on the following line is considered part
544 of the current command.
547 Here are the commands you can use in @command{ar} scripts, or when using
548 @command{ar} interactively. Three of them have special significance:
550 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
551 a temporary file required for most of the other commands.
553 @code{SAVE} commits the changes so far specified by the script. Prior
554 to @code{SAVE}, commands affect only the temporary copy of the current
558 @item ADDLIB @var{archive}
559 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
560 Add all the contents of @var{archive} (or, if specified, each named
561 @var{module} from @var{archive}) to the current archive.
563 Requires prior use of @code{OPEN} or @code{CREATE}.
565 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
566 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
567 @c else like "ar q..."
568 Add each named @var{member} as a module in the current archive.
570 Requires prior use of @code{OPEN} or @code{CREATE}.
573 Discard the contents of the current archive, canceling the effect of
574 any operations since the last @code{SAVE}. May be executed (with no
575 effect) even if no current archive is specified.
577 @item CREATE @var{archive}
578 Creates an archive, and makes it the current archive (required for many
579 other commands). The new archive is created with a temporary name; it
580 is not actually saved as @var{archive} until you use @code{SAVE}.
581 You can overwrite existing archives; similarly, the contents of any
582 existing file named @var{archive} will not be destroyed until @code{SAVE}.
584 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
585 Delete each listed @var{module} from the current archive; equivalent to
586 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
588 Requires prior use of @code{OPEN} or @code{CREATE}.
590 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
591 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
592 List each named @var{module} present in @var{archive}. The separate
593 command @code{VERBOSE} specifies the form of the output: when verbose
594 output is off, output is like that of @samp{ar -t @var{archive}
595 @var{module}@dots{}}. When verbose output is on, the listing is like
596 @samp{ar -tv @var{archive} @var{module}@dots{}}.
598 Output normally goes to the standard output stream; however, if you
599 specify @var{outputfile} as a final argument, @command{ar} directs the
603 Exit from @command{ar}, with a @code{0} exit code to indicate successful
604 completion. This command does not save the output file; if you have
605 changed the current archive since the last @code{SAVE} command, those
608 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
609 Extract each named @var{module} from the current archive, writing them
610 into the current directory as separate files. Equivalent to @samp{ar -x
611 @var{archive} @var{module}@dots{}}.
613 Requires prior use of @code{OPEN} or @code{CREATE}.
616 @c FIXME Tokens but no commands???
623 Display full contents of the current archive, in ``verbose'' style
624 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
625 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
626 enhancement, rather than present for MRI compatibility.)
628 Requires prior use of @code{OPEN} or @code{CREATE}.
630 @item OPEN @var{archive}
631 Opens an existing archive for use as the current archive (required for
632 many other commands). Any changes as the result of subsequent commands
633 will not actually affect @var{archive} until you next use @code{SAVE}.
635 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
636 In the current archive, replace each existing @var{module} (named in
637 the @code{REPLACE} arguments) from files in the current working directory.
638 To execute this command without errors, both the file, and the module in
639 the current archive, must exist.
641 Requires prior use of @code{OPEN} or @code{CREATE}.
644 Toggle an internal flag governing the output from @code{DIRECTORY}.
645 When the flag is on, @code{DIRECTORY} output matches output from
646 @samp{ar -tv }@dots{}.
649 Commit your changes to the current archive, and actually save it as a
650 file with the name specified in the last @code{CREATE} or @code{OPEN}
653 Requires prior use of @code{OPEN} or @code{CREATE}.
662 The @sc{gnu} linker @command{ld} is now described in a separate manual.
663 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
671 @c man title nm list symbols from object files
674 @c man begin SYNOPSIS nm
675 nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}]
676 [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}]
677 [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}]
678 [@option{-A}|@option{-o}|@option{--print-file-name}][@option{--special-syms}]
679 [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}]
680 [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}]
681 [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}]
682 [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}]
683 [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}]
684 [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}]
688 @c man begin DESCRIPTION nm
689 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
690 If no object files are listed as arguments, @command{nm} assumes the file
693 For each symbol, @command{nm} shows:
697 The symbol value, in the radix selected by options (see below), or
698 hexadecimal by default.
701 The symbol type. At least the following types are used; others are, as
702 well, depending on the object file format. If lowercase, the symbol is
703 local; if uppercase, the symbol is global (external).
705 @c Some more detail on exactly what these symbol types are used for
709 The symbol's value is absolute, and will not be changed by further
713 The symbol is in the uninitialized data section (known as BSS).
716 The symbol is common. Common symbols are uninitialized data. When
717 linking, multiple common symbols may appear with the same name. If the
718 symbol is defined anywhere, the common symbols are treated as undefined
721 For more details on common symbols, see the discussion of
722 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
726 The symbol is in the initialized data section.
729 The symbol is in an initialized data section for small objects. Some
730 object file formats permit more efficient access to small data objects,
731 such as a global int variable as opposed to a large global array.
734 The symbol is an indirect reference to another symbol. This is a @sc{gnu}
735 extension to the a.out object file format which is rarely used.
738 The symbol is a debugging symbol.
741 The symbol is in a read only data section.
744 The symbol is in an uninitialized data section for small objects.
747 The symbol is in the text (code) section.
750 The symbol is undefined.
753 The symbol is a weak object. When a weak defined symbol is linked with
754 a normal defined symbol, the normal defined symbol is used with no error.
755 When a weak undefined symbol is linked and the symbol is not defined,
756 the value of the weak symbol becomes zero with no error.
759 The symbol is a weak symbol that has not been specifically tagged as a
760 weak object symbol. When a weak defined symbol is linked with a normal
761 defined symbol, the normal defined symbol is used with no error.
762 When a weak undefined symbol is linked and the symbol is not defined,
763 the value of the symbol is determined in a system-specific manner without
764 error. On some systems, uppercase indicates that a default value has been
769 The symbol is a stabs symbol in an a.out object file. In this case, the
770 next values printed are the stabs other field, the stabs desc field, and
771 the stab type. Stabs symbols are used to hold debugging information.
773 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
774 ``stabs'' debug format}.
778 The symbol type is unknown, or object file format specific.
787 @c man begin OPTIONS nm
788 The long and short forms of options, shown here as alternatives, are
794 @itemx --print-file-name
795 @cindex input file name
797 @cindex source file name
798 Precede each symbol by the name of the input file (or archive member)
799 in which it was found, rather than identifying the input file once only,
800 before all of its symbols.
804 @cindex debugging symbols
805 Display all symbols, even debugger-only symbols; normally these are not
809 @cindex @command{nm} format
810 @cindex @command{nm} compatibility
811 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
814 @itemx --demangle[=@var{style}]
815 @cindex demangling in nm
816 Decode (@dfn{demangle}) low-level symbol names into user-level names.
817 Besides removing any initial underscore prepended by the system, this
818 makes C++ function names readable. Different compilers have different
819 mangling styles. The optional demangling style argument can be used to
820 choose an appropriate demangling style for your compiler. @xref{c++filt},
821 for more information on demangling.
824 Do not demangle low-level symbol names. This is the default.
828 @cindex dynamic symbols
829 Display the dynamic symbols rather than the normal symbols. This is
830 only meaningful for dynamic objects, such as certain types of shared
833 @item -f @var{format}
834 @itemx --format=@var{format}
835 @cindex @command{nm} format
836 @cindex @command{nm} compatibility
837 Use the output format @var{format}, which can be @code{bsd},
838 @code{sysv}, or @code{posix}. The default is @code{bsd}.
839 Only the first character of @var{format} is significant; it can be
840 either upper or lower case.
844 @cindex external symbols
845 Display only external symbols.
848 @itemx --line-numbers
849 @cindex symbol line numbers
850 For each symbol, use debugging information to try to find a filename and
851 line number. For a defined symbol, look for the line number of the
852 address of the symbol. For an undefined symbol, look for the line
853 number of a relocation entry which refers to the symbol. If line number
854 information can be found, print it after the other symbol information.
858 @itemx --numeric-sort
859 Sort symbols numerically by their addresses, rather than alphabetically
864 @cindex sorting symbols
865 Do not bother to sort the symbols in any order; print them in the order
870 Use the POSIX.2 standard output format instead of the default format.
871 Equivalent to @samp{-f posix}.
875 Print size, not the value, of defined symbols for the @code{bsd} output format.
879 @cindex symbol index, listing
880 When listing symbols from archive members, include the index: a mapping
881 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
882 contain definitions for which names.
885 @itemx --reverse-sort
886 Reverse the order of the sort (whether numeric or alphabetic); let the
890 Sort symbols by size. The size is computed as the difference between
891 the value of the symbol and the value of the symbol with the next higher
892 value. If the @code{bsd} output format is used the size of the symbol
893 is printed, rather than the value, and @samp{-S} must be used in order
894 both size and value to be printed.
897 Display symbols which have a target-specific special meaning. These
898 symbols are usually used by the target for some special processing and
899 are not normally helpful when included included in the normal symbol
900 lists. For example for ARM targets this option would skip the mapping
901 symbols used to mark transitions between ARM code, THUMB code and
905 @itemx --radix=@var{radix}
906 Use @var{radix} as the radix for printing the symbol values. It must be
907 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
909 @item --target=@var{bfdname}
910 @cindex object code format
911 Specify an object code format other than your system's default format.
912 @xref{Target Selection}, for more information.
915 @itemx --undefined-only
916 @cindex external symbols
917 @cindex undefined symbols
918 Display only undefined symbols (those external to each object file).
921 @cindex external symbols
922 @cindex undefined symbols
923 Display only defined symbols for each object file.
927 Show the version number of @command{nm} and exit.
930 This option is ignored for compatibility with the AIX version of
931 @command{nm}. It takes one parameter which must be the string
932 @option{32_64}. The default mode of AIX @command{nm} corresponds
933 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
936 Show a summary of the options to @command{nm} and exit.
942 @c man begin SEEALSO nm
943 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
950 @c man title objcopy copy and translate object files
953 @c man begin SYNOPSIS objcopy
954 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
955 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
956 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
957 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
958 [@option{-S}|@option{--strip-all}]
959 [@option{-g}|@option{--strip-debug}]
960 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
961 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
962 [@option{--strip-unneeded-symbol=}@var{symbolname}]
963 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
964 [@option{--localize-hidden}]
965 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
966 [@option{--globalize-symbol=}@var{symbolname}]
967 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
968 [@option{-w}|@option{--wildcard}]
969 [@option{-x}|@option{--discard-all}]
970 [@option{-X}|@option{--discard-locals}]
971 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
972 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
973 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
974 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
975 [@option{-p}|@option{--preserve-dates}]
976 [@option{--debugging}]
977 [@option{--gap-fill=}@var{val}]
978 [@option{--pad-to=}@var{address}]
979 [@option{--set-start=}@var{val}]
980 [@option{--adjust-start=}@var{incr}]
981 [@option{--change-addresses=}@var{incr}]
982 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
983 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
984 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
985 [@option{--change-warnings}] [@option{--no-change-warnings}]
986 [@option{--set-section-flags} @var{section}=@var{flags}]
987 [@option{--add-section} @var{sectionname}=@var{filename}]
988 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
989 [@option{--change-leading-char}] [@option{--remove-leading-char}]
990 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
991 [@option{--redefine-sym} @var{old}=@var{new}]
992 [@option{--redefine-syms=}@var{filename}]
994 [@option{--keep-symbols=}@var{filename}]
995 [@option{--strip-symbols=}@var{filename}]
996 [@option{--strip-unneeded-symbols=}@var{filename}]
997 [@option{--keep-global-symbols=}@var{filename}]
998 [@option{--localize-symbols=}@var{filename}]
999 [@option{--globalize-symbols=}@var{filename}]
1000 [@option{--weaken-symbols=}@var{filename}]
1001 [@option{--alt-machine-code=}@var{index}]
1002 [@option{--prefix-symbols=}@var{string}]
1003 [@option{--prefix-sections=}@var{string}]
1004 [@option{--prefix-alloc-sections=}@var{string}]
1005 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1006 [@option{--keep-file-symbols}]
1007 [@option{--only-keep-debug}]
1008 [@option{--extract-symbol}]
1009 [@option{--writable-text}]
1010 [@option{--readonly-text}]
1013 [@option{-v}|@option{--verbose}]
1014 [@option{-V}|@option{--version}]
1015 [@option{--help}] [@option{--info}]
1016 @var{infile} [@var{outfile}]
1020 @c man begin DESCRIPTION objcopy
1021 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1022 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1023 read and write the object files. It can write the destination object
1024 file in a format different from that of the source object file. The
1025 exact behavior of @command{objcopy} is controlled by command-line options.
1026 Note that @command{objcopy} should be able to copy a fully linked file
1027 between any two formats. However, copying a relocatable object file
1028 between any two formats may not work as expected.
1030 @command{objcopy} creates temporary files to do its translations and
1031 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1032 translation work; it has access to all the formats described in @sc{bfd}
1033 and thus is able to recognize most formats without being told
1034 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1036 @command{objcopy} can be used to generate S-records by using an output
1037 target of @samp{srec} (e.g., use @samp{-O srec}).
1039 @command{objcopy} can be used to generate a raw binary file by using an
1040 output target of @samp{binary} (e.g., use @option{-O binary}). When
1041 @command{objcopy} generates a raw binary file, it will essentially produce
1042 a memory dump of the contents of the input object file. All symbols and
1043 relocation information will be discarded. The memory dump will start at
1044 the load address of the lowest section copied into the output file.
1046 When generating an S-record or a raw binary file, it may be helpful to
1047 use @option{-S} to remove sections containing debugging information. In
1048 some cases @option{-R} will be useful to remove sections which contain
1049 information that is not needed by the binary file.
1051 Note---@command{objcopy} is not able to change the endianness of its input
1052 files. If the input format has an endianness (some formats do not),
1053 @command{objcopy} can only copy the inputs into file formats that have the
1054 same endianness or which have no endianness (e.g., @samp{srec}).
1058 @c man begin OPTIONS objcopy
1062 @itemx @var{outfile}
1063 The input and output files, respectively.
1064 If you do not specify @var{outfile}, @command{objcopy} creates a
1065 temporary file and destructively renames the result with
1066 the name of @var{infile}.
1068 @item -I @var{bfdname}
1069 @itemx --input-target=@var{bfdname}
1070 Consider the source file's object format to be @var{bfdname}, rather than
1071 attempting to deduce it. @xref{Target Selection}, for more information.
1073 @item -O @var{bfdname}
1074 @itemx --output-target=@var{bfdname}
1075 Write the output file using the object format @var{bfdname}.
1076 @xref{Target Selection}, for more information.
1078 @item -F @var{bfdname}
1079 @itemx --target=@var{bfdname}
1080 Use @var{bfdname} as the object format for both the input and the output
1081 file; i.e., simply transfer data from source to destination with no
1082 translation. @xref{Target Selection}, for more information.
1084 @item -B @var{bfdarch}
1085 @itemx --binary-architecture=@var{bfdarch}
1086 Useful when transforming a raw binary input file into an object file.
1087 In this case the output architecture can be set to @var{bfdarch}. This
1088 option will be ignored if the input file has a known @var{bfdarch}. You
1089 can access this binary data inside a program by referencing the special
1090 symbols that are created by the conversion process. These symbols are
1091 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1092 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1093 an object file and then access it in your code using these symbols.
1095 @item -j @var{sectionname}
1096 @itemx --only-section=@var{sectionname}
1097 Copy only the named section from the input file to the output file.
1098 This option may be given more than once. Note that using this option
1099 inappropriately may make the output file unusable.
1101 @item -R @var{sectionname}
1102 @itemx --remove-section=@var{sectionname}
1103 Remove any section named @var{sectionname} from the output file. This
1104 option may be given more than once. Note that using this option
1105 inappropriately may make the output file unusable.
1109 Do not copy relocation and symbol information from the source file.
1112 @itemx --strip-debug
1113 Do not copy debugging symbols or sections from the source file.
1115 @item --strip-unneeded
1116 Strip all symbols that are not needed for relocation processing.
1118 @item -K @var{symbolname}
1119 @itemx --keep-symbol=@var{symbolname}
1120 When stripping symbols, keep symbol @var{symbolname} even if it would
1121 normally be stripped. This option may be given more than once.
1123 @item -N @var{symbolname}
1124 @itemx --strip-symbol=@var{symbolname}
1125 Do not copy symbol @var{symbolname} from the source file. This option
1126 may be given more than once.
1128 @item --strip-unneeded-symbol=@var{symbolname}
1129 Do not copy symbol @var{symbolname} from the source file unless it is needed
1130 by a relocation. This option may be given more than once.
1132 @item -G @var{symbolname}
1133 @itemx --keep-global-symbol=@var{symbolname}
1134 Keep only symbol @var{symbolname} global. Make all other symbols local
1135 to the file, so that they are not visible externally. This option may
1136 be given more than once.
1138 @item --localize-hidden
1139 In an ELF object, mark all symbols that have hidden or internal visibility
1140 as local. This option applies on top of symbol-specific localization options
1141 such as @option{-L}.
1143 @item -L @var{symbolname}
1144 @itemx --localize-symbol=@var{symbolname}
1145 Make symbol @var{symbolname} local to the file, so that it is not
1146 visible externally. This option may be given more than once.
1148 @item -W @var{symbolname}
1149 @itemx --weaken-symbol=@var{symbolname}
1150 Make symbol @var{symbolname} weak. This option may be given more than once.
1152 @item --globalize-symbol=@var{symbolname}
1153 Give symbol @var{symbolname} global scoping so that it is visible
1154 outside of the file in which it is defined. This option may be given
1159 Permit regular expressions in @var{symbolname}s used in other command
1160 line options. The question mark (?), asterisk (*), backslash (\) and
1161 square brackets ([]) operators can be used anywhere in the symbol
1162 name. If the first character of the symbol name is the exclamation
1163 point (!) then the sense of the switch is reversed for that symbol.
1170 would cause objcopy to weaken all symbols that start with ``fo''
1171 except for the symbol ``foo''.
1174 @itemx --discard-all
1175 Do not copy non-global symbols from the source file.
1176 @c FIXME any reason to prefer "non-global" to "local" here?
1179 @itemx --discard-locals
1180 Do not copy compiler-generated local symbols.
1181 (These usually start with @samp{L} or @samp{.}.)
1184 @itemx --byte=@var{byte}
1185 Keep only every @var{byte}th byte of the input file (header data is not
1186 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1187 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1188 option, or the default of 4. This option is useful for creating files
1189 to program @sc{rom}. It is typically used with an @code{srec} output
1192 @item -i @var{interleave}
1193 @itemx --interleave=@var{interleave}
1194 Only copy one out of every @var{interleave} bytes. Select which byte to
1195 copy with the @option{-b} or @option{--byte} option. The default is 4.
1196 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1200 @itemx --preserve-dates
1201 Set the access and modification dates of the output file to be the same
1202 as those of the input file.
1205 Convert debugging information, if possible. This is not the default
1206 because only certain debugging formats are supported, and the
1207 conversion process can be time consuming.
1209 @item --gap-fill @var{val}
1210 Fill gaps between sections with @var{val}. This operation applies to
1211 the @emph{load address} (LMA) of the sections. It is done by increasing
1212 the size of the section with the lower address, and filling in the extra
1213 space created with @var{val}.
1215 @item --pad-to @var{address}
1216 Pad the output file up to the load address @var{address}. This is
1217 done by increasing the size of the last section. The extra space is
1218 filled in with the value specified by @option{--gap-fill} (default zero).
1220 @item --set-start @var{val}
1221 Set the start address of the new file to @var{val}. Not all object file
1222 formats support setting the start address.
1224 @item --change-start @var{incr}
1225 @itemx --adjust-start @var{incr}
1226 @cindex changing start address
1227 Change the start address by adding @var{incr}. Not all object file
1228 formats support setting the start address.
1230 @item --change-addresses @var{incr}
1231 @itemx --adjust-vma @var{incr}
1232 @cindex changing object addresses
1233 Change the VMA and LMA addresses of all sections, as well as the start
1234 address, by adding @var{incr}. Some object file formats do not permit
1235 section addresses to be changed arbitrarily. Note that this does not
1236 relocate the sections; if the program expects sections to be loaded at a
1237 certain address, and this option is used to change the sections such
1238 that they are loaded at a different address, the program may fail.
1240 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1241 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1242 @cindex changing section address
1243 Set or change both the VMA address and the LMA address of the named
1244 @var{section}. If @samp{=} is used, the section address is set to
1245 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1246 section address. See the comments under @option{--change-addresses},
1247 above. If @var{section} does not exist in the input file, a warning will
1248 be issued, unless @option{--no-change-warnings} is used.
1250 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1251 @cindex changing section LMA
1252 Set or change the LMA address of the named @var{section}. The LMA
1253 address is the address where the section will be loaded into memory at
1254 program load time. Normally this is the same as the VMA address, which
1255 is the address of the section at program run time, but on some systems,
1256 especially those where a program is held in ROM, the two can be
1257 different. If @samp{=} is used, the section address is set to
1258 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1259 section address. See the comments under @option{--change-addresses},
1260 above. If @var{section} does not exist in the input file, a warning
1261 will be issued, unless @option{--no-change-warnings} is used.
1263 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1264 @cindex changing section VMA
1265 Set or change the VMA address of the named @var{section}. The VMA
1266 address is the address where the section will be located once the
1267 program has started executing. Normally this is the same as the LMA
1268 address, which is the address where the section will be loaded into
1269 memory, but on some systems, especially those where a program is held in
1270 ROM, the two can be different. If @samp{=} is used, the section address
1271 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1272 from the section address. See the comments under
1273 @option{--change-addresses}, above. If @var{section} does not exist in
1274 the input file, a warning will be issued, unless
1275 @option{--no-change-warnings} is used.
1277 @item --change-warnings
1278 @itemx --adjust-warnings
1279 If @option{--change-section-address} or @option{--change-section-lma} or
1280 @option{--change-section-vma} is used, and the named section does not
1281 exist, issue a warning. This is the default.
1283 @item --no-change-warnings
1284 @itemx --no-adjust-warnings
1285 Do not issue a warning if @option{--change-section-address} or
1286 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1287 if the named section does not exist.
1289 @item --set-section-flags @var{section}=@var{flags}
1290 Set the flags for the named section. The @var{flags} argument is a
1291 comma separated string of flag names. The recognized names are
1292 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1293 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1294 @samp{debug}. You can set the @samp{contents} flag for a section which
1295 does not have contents, but it is not meaningful to clear the
1296 @samp{contents} flag of a section which does have contents--just remove
1297 the section instead. Not all flags are meaningful for all object file
1300 @item --add-section @var{sectionname}=@var{filename}
1301 Add a new section named @var{sectionname} while copying the file. The
1302 contents of the new section are taken from the file @var{filename}. The
1303 size of the section will be the size of the file. This option only
1304 works on file formats which can support sections with arbitrary names.
1306 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1307 Rename a section from @var{oldname} to @var{newname}, optionally
1308 changing the section's flags to @var{flags} in the process. This has
1309 the advantage over usng a linker script to perform the rename in that
1310 the output stays as an object file and does not become a linked
1313 This option is particularly helpful when the input format is binary,
1314 since this will always create a section called .data. If for example,
1315 you wanted instead to create a section called .rodata containing binary
1316 data you could use the following command line to achieve it:
1319 objcopy -I binary -O <output_format> -B <architecture> \
1320 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1321 <input_binary_file> <output_object_file>
1324 @item --change-leading-char
1325 Some object file formats use special characters at the start of
1326 symbols. The most common such character is underscore, which compilers
1327 often add before every symbol. This option tells @command{objcopy} to
1328 change the leading character of every symbol when it converts between
1329 object file formats. If the object file formats use the same leading
1330 character, this option has no effect. Otherwise, it will add a
1331 character, or remove a character, or change a character, as
1334 @item --remove-leading-char
1335 If the first character of a global symbol is a special symbol leading
1336 character used by the object file format, remove the character. The
1337 most common symbol leading character is underscore. This option will
1338 remove a leading underscore from all global symbols. This can be useful
1339 if you want to link together objects of different file formats with
1340 different conventions for symbol names. This is different from
1341 @option{--change-leading-char} because it always changes the symbol name
1342 when appropriate, regardless of the object file format of the output
1345 @item --srec-len=@var{ival}
1346 Meaningful only for srec output. Set the maximum length of the Srecords
1347 being produced to @var{ival}. This length covers both address, data and
1350 @item --srec-forceS3
1351 Meaningful only for srec output. Avoid generation of S1/S2 records,
1352 creating S3-only record format.
1354 @item --redefine-sym @var{old}=@var{new}
1355 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1356 when one is trying link two things together for which you have no
1357 source, and there are name collisions.
1359 @item --redefine-syms=@var{filename}
1360 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1361 listed in the file @var{filename}. @var{filename} is simply a flat file,
1362 with one symbol pair per line. Line comments may be introduced by the hash
1363 character. This option may be given more than once.
1366 Change all global symbols in the file to be weak. This can be useful
1367 when building an object which will be linked against other objects using
1368 the @option{-R} option to the linker. This option is only effective when
1369 using an object file format which supports weak symbols.
1371 @item --keep-symbols=@var{filename}
1372 Apply @option{--keep-symbol} option to each symbol listed in the file
1373 @var{filename}. @var{filename} is simply a flat file, with one symbol
1374 name per line. Line comments may be introduced by the hash character.
1375 This option may be given more than once.
1377 @item --strip-symbols=@var{filename}
1378 Apply @option{--strip-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 --strip-unneeded-symbols=@var{filename}
1384 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1385 the file @var{filename}. @var{filename} is simply a flat file, with one
1386 symbol name per line. Line comments may be introduced by the hash
1387 character. This option may be given more than once.
1389 @item --keep-global-symbols=@var{filename}
1390 Apply @option{--keep-global-symbol} option to each symbol listed in the
1391 file @var{filename}. @var{filename} is simply a flat file, with one
1392 symbol name per line. Line comments may be introduced by the hash
1393 character. This option may be given more than once.
1395 @item --localize-symbols=@var{filename}
1396 Apply @option{--localize-symbol} option to each symbol listed in the file
1397 @var{filename}. @var{filename} is simply a flat file, with one symbol
1398 name per line. Line comments may be introduced by the hash character.
1399 This option may be given more than once.
1401 @item --globalize-symbols=@var{filename}
1402 Apply @option{--globalize-symbol} option to each symbol listed in the file
1403 @var{filename}. @var{filename} is simply a flat file, with one symbol
1404 name per line. Line comments may be introduced by the hash character.
1405 This option may be given more than once.
1407 @item --weaken-symbols=@var{filename}
1408 Apply @option{--weaken-symbol} option to each symbol listed in the file
1409 @var{filename}. @var{filename} is simply a flat file, with one symbol
1410 name per line. Line comments may be introduced by the hash character.
1411 This option may be given more than once.
1413 @item --alt-machine-code=@var{index}
1414 If the output architecture has alternate machine codes, use the
1415 @var{index}th code instead of the default one. This is useful in case
1416 a machine is assigned an official code and the tool-chain adopts the
1417 new code, but other applications still depend on the original code
1418 being used. For ELF based architectures if the @var{index}
1419 alternative does not exist then the value is treated as an absolute
1420 number to be stored in the e_machine field of the ELF header.
1422 @item --writable-text
1423 Mark the output text as writable. This option isn't meaningful for all
1424 object file formats.
1426 @item --readonly-text
1427 Make the output text write protected. This option isn't meaningful for all
1428 object file formats.
1431 Mark the output file as demand paged. This option isn't meaningful for all
1432 object file formats.
1435 Mark the output file as impure. This option isn't meaningful for all
1436 object file formats.
1438 @item --prefix-symbols=@var{string}
1439 Prefix all symbols in the output file with @var{string}.
1441 @item --prefix-sections=@var{string}
1442 Prefix all section names in the output file with @var{string}.
1444 @item --prefix-alloc-sections=@var{string}
1445 Prefix all the names of all allocated sections in the output file with
1448 @item --add-gnu-debuglink=@var{path-to-file}
1449 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1450 and adds it to the output file.
1452 @item --keep-file-symbols
1453 When stripping a file, perhaps with @option{--strip-debug} or
1454 @option{--strip-unneeded}, retain any symbols specifying source file names,
1455 which would otherwise get stripped.
1457 @item --only-keep-debug
1458 Strip a file, removing contents of any sections that would not be
1459 stripped by @option{--strip-debug} and leaving the debugging sections
1462 The intention is that this option will be used in conjunction with
1463 @option{--add-gnu-debuglink} to create a two part executable. One a
1464 stripped binary which will occupy less space in RAM and in a
1465 distribution and the second a debugging information file which is only
1466 needed if debugging abilities are required. The suggested procedure
1467 to create these files is as follows:
1470 @item Link the executable as normal. Assuming that is is called
1472 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1473 create a file containing the debugging info.
1474 @item Run @code{objcopy --strip-debug foo} to create a
1475 stripped executable.
1476 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1477 to add a link to the debugging info into the stripped executable.
1480 Note - the choice of @code{.dbg} as an extension for the debug info
1481 file is arbitrary. Also the @code{--only-keep-debug} step is
1482 optional. You could instead do this:
1485 @item Link the executable as normal.
1486 @item Copy @code{foo} to @code{foo.full}
1487 @item Run @code{objcopy --strip-debug foo}
1488 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1491 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1492 full executable. It does not have to be a file created by the
1493 @option{--only-keep-debug} switch.
1495 Note - this switch is only intended for use on fully linked files. It
1496 does not make sense to use it on object files where the debugging
1497 information may be incomplete. Besides the gnu_debuglink feature
1498 currently only supports the presence of one filename containing
1499 debugging information, not multiple filenames on a one-per-object-file
1502 @item --extract-symbol
1503 Keep the file's section flags and symbols but remove all section data.
1504 Specifically, the option:
1507 @item sets the virtual and load addresses of every section to zero;
1508 @item removes the contents of all sections;
1509 @item sets the size of every section to zero; and
1510 @item sets the file's start address to zero.
1513 This option is used to build a @file{.sym} file for a VxWorks kernel.
1514 It can also be a useful way of reducing the size of a @option{--just-symbols}
1519 Show the version number of @command{objcopy}.
1523 Verbose output: list all object files modified. In the case of
1524 archives, @samp{objcopy -V} lists all members of the archive.
1527 Show a summary of the options to @command{objcopy}.
1530 Display a list showing all architectures and object formats available.
1536 @c man begin SEEALSO objcopy
1537 ld(1), objdump(1), and the Info entries for @file{binutils}.
1544 @cindex object file information
1547 @c man title objdump display information from object files.
1550 @c man begin SYNOPSIS objdump
1551 objdump [@option{-a}|@option{--archive-headers}]
1552 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1553 [@option{-C}|@option{--demangle}[=@var{style}] ]
1554 [@option{-d}|@option{--disassemble}]
1555 [@option{-D}|@option{--disassemble-all}]
1556 [@option{-z}|@option{--disassemble-zeroes}]
1557 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1558 [@option{-f}|@option{--file-headers}]
1559 [@option{--file-start-context}]
1560 [@option{-g}|@option{--debugging}]
1561 [@option{-e}|@option{--debugging-tags}]
1562 [@option{-h}|@option{--section-headers}|@option{--headers}]
1563 [@option{-i}|@option{--info}]
1564 [@option{-j} @var{section}|@option{--section=}@var{section}]
1565 [@option{-l}|@option{--line-numbers}]
1566 [@option{-S}|@option{--source}]
1567 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1568 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1569 [@option{-p}|@option{--private-headers}]
1570 [@option{-r}|@option{--reloc}]
1571 [@option{-R}|@option{--dynamic-reloc}]
1572 [@option{-s}|@option{--full-contents}]
1573 [@option{-W}|@option{--dwarf}]
1574 [@option{-G}|@option{--stabs}]
1575 [@option{-t}|@option{--syms}]
1576 [@option{-T}|@option{--dynamic-syms}]
1577 [@option{-x}|@option{--all-headers}]
1578 [@option{-w}|@option{--wide}]
1579 [@option{--start-address=}@var{address}]
1580 [@option{--stop-address=}@var{address}]
1581 [@option{--prefix-addresses}]
1582 [@option{--[no-]show-raw-insn}]
1583 [@option{--adjust-vma=}@var{offset}]
1584 [@option{--special-syms}]
1585 [@option{-V}|@option{--version}]
1586 [@option{-H}|@option{--help}]
1587 @var{objfile}@dots{}
1591 @c man begin DESCRIPTION objdump
1593 @command{objdump} displays information about one or more object files.
1594 The options control what particular information to display. This
1595 information is mostly useful to programmers who are working on the
1596 compilation tools, as opposed to programmers who just want their
1597 program to compile and work.
1599 @var{objfile}@dots{} are the object files to be examined. When you
1600 specify archives, @command{objdump} shows information on each of the member
1605 @c man begin OPTIONS objdump
1607 The long and short forms of options, shown here as alternatives, are
1608 equivalent. At least one option from the list
1609 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1613 @itemx --archive-header
1614 @cindex archive headers
1615 If any of the @var{objfile} files are archives, display the archive
1616 header information (in a format similar to @samp{ls -l}). Besides the
1617 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1618 the object file format of each archive member.
1620 @item --adjust-vma=@var{offset}
1621 @cindex section addresses in objdump
1622 @cindex VMA in objdump
1623 When dumping information, first add @var{offset} to all the section
1624 addresses. This is useful if the section addresses do not correspond to
1625 the symbol table, which can happen when putting sections at particular
1626 addresses when using a format which can not represent section addresses,
1629 @item -b @var{bfdname}
1630 @itemx --target=@var{bfdname}
1631 @cindex object code format
1632 Specify that the object-code format for the object files is
1633 @var{bfdname}. This option may not be necessary; @var{objdump} can
1634 automatically recognize many formats.
1638 objdump -b oasys -m vax -h fu.o
1641 displays summary information from the section headers (@option{-h}) of
1642 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1643 file in the format produced by Oasys compilers. You can list the
1644 formats available with the @option{-i} option.
1645 @xref{Target Selection}, for more information.
1648 @itemx --demangle[=@var{style}]
1649 @cindex demangling in objdump
1650 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1651 Besides removing any initial underscore prepended by the system, this
1652 makes C++ function names readable. Different compilers have different
1653 mangling styles. The optional demangling style argument can be used to
1654 choose an appropriate demangling style for your compiler. @xref{c++filt},
1655 for more information on demangling.
1659 Display debugging information. This attempts to parse debugging
1660 information stored in the file and print it out using a C like syntax.
1661 Only certain types of debugging information have been implemented.
1662 Some other types are supported by @command{readelf -w}.
1666 @itemx --debugging-tags
1667 Like @option{-g}, but the information is generated in a format compatible
1671 @itemx --disassemble
1672 @cindex disassembling object code
1673 @cindex machine instructions
1674 Display the assembler mnemonics for the machine instructions from
1675 @var{objfile}. This option only disassembles those sections which are
1676 expected to contain instructions.
1679 @itemx --disassemble-all
1680 Like @option{-d}, but disassemble the contents of all sections, not just
1681 those expected to contain instructions.
1683 @item --prefix-addresses
1684 When disassembling, print the complete address on each line. This is
1685 the older disassembly format.
1689 @itemx --endian=@{big|little@}
1691 @cindex disassembly endianness
1692 Specify the endianness of the object files. This only affects
1693 disassembly. This can be useful when disassembling a file format which
1694 does not describe endianness information, such as S-records.
1697 @itemx --file-headers
1698 @cindex object file header
1699 Display summary information from the overall header of
1700 each of the @var{objfile} files.
1702 @item --file-start-context
1703 @cindex source code context
1704 Specify that when displaying interlisted source code/disassembly
1705 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1706 context to the start of the file.
1709 @itemx --section-headers
1711 @cindex section headers
1712 Display summary information from the section headers of the
1715 File segments may be relocated to nonstandard addresses, for example by
1716 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1717 @command{ld}. However, some object file formats, such as a.out, do not
1718 store the starting address of the file segments. In those situations,
1719 although @command{ld} relocates the sections correctly, using @samp{objdump
1720 -h} to list the file section headers cannot show the correct addresses.
1721 Instead, it shows the usual addresses, which are implicit for the
1726 Print a summary of the options to @command{objdump} and exit.
1730 @cindex architectures available
1731 @cindex object formats available
1732 Display a list showing all architectures and object formats available
1733 for specification with @option{-b} or @option{-m}.
1736 @itemx --section=@var{name}
1737 @cindex section information
1738 Display information only for section @var{name}.
1741 @itemx --line-numbers
1742 @cindex source filenames for object files
1743 Label the display (using debugging information) with the filename and
1744 source line numbers corresponding to the object code or relocs shown.
1745 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1747 @item -m @var{machine}
1748 @itemx --architecture=@var{machine}
1749 @cindex architecture
1750 @cindex disassembly architecture
1751 Specify the architecture to use when disassembling object files. This
1752 can be useful when disassembling object files which do not describe
1753 architecture information, such as S-records. You can list the available
1754 architectures with the @option{-i} option.
1756 @item -M @var{options}
1757 @itemx --disassembler-options=@var{options}
1758 Pass target specific information to the disassembler. Only supported on
1759 some targets. If it is necessary to specify more than one
1760 disassembler option then multiple @option{-M} options can be used or
1761 can be placed together into a comma separated list.
1763 If the target is an ARM architecture then this switch can be used to
1764 select which register name set is used during disassembler. Specifying
1765 @option{-M reg-names-std} (the default) will select the register names as
1766 used in ARM's instruction set documentation, but with register 13 called
1767 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1768 @option{-M reg-names-apcs} will select the name set used by the ARM
1769 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1770 just use @samp{r} followed by the register number.
1772 There are also two variants on the APCS register naming scheme enabled
1773 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1774 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1775 with the normal register names or the special register names).
1777 This option can also be used for ARM architectures to force the
1778 disassembler to interpret all instructions as Thumb instructions by
1779 using the switch @option{--disassembler-options=force-thumb}. This can be
1780 useful when attempting to disassemble thumb code produced by other
1783 For the x86, some of the options duplicate functions of the @option{-m}
1784 switch, but allow finer grained control. Multiple selections from the
1785 following may be specified as a comma separated string.
1786 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1787 the given architecture. @option{intel} and @option{att} select between
1788 intel syntax mode and AT&T syntax mode. @option{addr64}, @option{addr32},
1789 @option{addr16}, @option{data32} and @option{data16} specify the default
1790 address size and operand size. These four options will be overridden if
1791 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1792 option string. Lastly, @option{suffix}, when in AT&T mode,
1793 instructs the disassembler to print a mnemonic suffix even when the
1794 suffix could be inferred by the operands.
1796 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1797 disassembly of BookE instructions. @option{32} and @option{64} select
1798 PowerPC and PowerPC64 disassembly, respectively. @option{e300} selects
1799 disassembly for the e300 family. @option{440} selects disassembly for
1802 For MIPS, this option controls the printing of instruction mnemonic
1803 names and register names in disassembled instructions. Multiple
1804 selections from the following may be specified as a comma separated
1805 string, and invalid options are ignored:
1809 Print the 'raw' instruction mnemonic instead of some pseudo
1810 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
1811 'sll' instead of 'nop', etc.
1813 @item gpr-names=@var{ABI}
1814 Print GPR (general-purpose register) names as appropriate
1815 for the specified ABI. By default, GPR names are selected according to
1816 the ABI of the binary being disassembled.
1818 @item fpr-names=@var{ABI}
1819 Print FPR (floating-point register) names as
1820 appropriate for the specified ABI. By default, FPR numbers are printed
1823 @item cp0-names=@var{ARCH}
1824 Print CP0 (system control coprocessor; coprocessor 0) register names
1825 as appropriate for the CPU or architecture specified by
1826 @var{ARCH}. By default, CP0 register names are selected according to
1827 the architecture and CPU of the binary being disassembled.
1829 @item hwr-names=@var{ARCH}
1830 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1831 as appropriate for the CPU or architecture specified by
1832 @var{ARCH}. By default, HWR names are selected according to
1833 the architecture and CPU of the binary being disassembled.
1835 @item reg-names=@var{ABI}
1836 Print GPR and FPR names as appropriate for the selected ABI.
1838 @item reg-names=@var{ARCH}
1839 Print CPU-specific register names (CP0 register and HWR names)
1840 as appropriate for the selected CPU or architecture.
1843 For any of the options listed above, @var{ABI} or
1844 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1845 rather than names, for the selected types of registers.
1846 You can list the available values of @var{ABI} and @var{ARCH} using
1847 the @option{--help} option.
1849 For VAX, you can specify function entry addresses with @option{-M
1850 entry:0xf00ba}. You can use this multiple times to properly
1851 disassemble VAX binary files that don't contain symbol tables (like
1852 ROM dumps). In these cases, the function entry mask would otherwise
1853 be decoded as VAX instructions, which would probably lead the rest
1854 of the function being wrongly disassembled.
1857 @itemx --private-headers
1858 Print information that is specific to the object file format. The exact
1859 information printed depends upon the object file format. For some
1860 object file formats, no additional information is printed.
1864 @cindex relocation entries, in object file
1865 Print the relocation entries of the file. If used with @option{-d} or
1866 @option{-D}, the relocations are printed interspersed with the
1870 @itemx --dynamic-reloc
1871 @cindex dynamic relocation entries, in object file
1872 Print the dynamic relocation entries of the file. This is only
1873 meaningful for dynamic objects, such as certain types of shared
1877 @itemx --full-contents
1878 @cindex sections, full contents
1879 @cindex object file sections
1880 Display the full contents of any sections requested. By default all
1881 non-empty sections are displayed.
1885 @cindex source disassembly
1886 @cindex disassembly, with source
1887 Display source code intermixed with disassembly, if possible. Implies
1890 @item --show-raw-insn
1891 When disassembling instructions, print the instruction in hex as well as
1892 in symbolic form. This is the default except when
1893 @option{--prefix-addresses} is used.
1895 @item --no-show-raw-insn
1896 When disassembling instructions, do not print the instruction bytes.
1897 This is the default when @option{--prefix-addresses} is used.
1902 @cindex debug symbols
1903 Displays the contents of the DWARF debug sections in the file, if any
1910 @cindex debug symbols
1911 @cindex ELF object file format
1912 Display the full contents of any sections requested. Display the
1913 contents of the .stab and .stab.index and .stab.excl sections from an
1914 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1915 @code{.stab} debugging symbol-table entries are carried in an ELF
1916 section. In most other file formats, debugging symbol-table entries are
1917 interleaved with linkage symbols, and are visible in the @option{--syms}
1920 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1921 Overview,stabs.info, The ``stabs'' debug format}.
1924 @item --start-address=@var{address}
1925 @cindex start-address
1926 Start displaying data at the specified address. This affects the output
1927 of the @option{-d}, @option{-r} and @option{-s} options.
1929 @item --stop-address=@var{address}
1930 @cindex stop-address
1931 Stop displaying data at the specified address. This affects the output
1932 of the @option{-d}, @option{-r} and @option{-s} options.
1936 @cindex symbol table entries, printing
1937 Print the symbol table entries of the file.
1938 This is similar to the information provided by the @samp{nm} program.
1941 @itemx --dynamic-syms
1942 @cindex dynamic symbol table entries, printing
1943 Print the dynamic symbol table entries of the file. This is only
1944 meaningful for dynamic objects, such as certain types of shared
1945 libraries. This is similar to the information provided by the @samp{nm}
1946 program when given the @option{-D} (@option{--dynamic}) option.
1948 @item --special-syms
1949 When displaying symbols include those which the target considers to be
1950 special in some way and which would not normally be of interest to the
1955 Print the version number of @command{objdump} and exit.
1958 @itemx --all-headers
1959 @cindex all header information, object file
1960 @cindex header information, all
1961 Display all available header information, including the symbol table and
1962 relocation entries. Using @option{-x} is equivalent to specifying all of
1963 @option{-a -f -h -p -r -t}.
1967 @cindex wide output, printing
1968 Format some lines for output devices that have more than 80 columns.
1969 Also do not truncate symbol names when they are displayed.
1972 @itemx --disassemble-zeroes
1973 Normally the disassembly output will skip blocks of zeroes. This
1974 option directs the disassembler to disassemble those blocks, just like
1981 @c man begin SEEALSO objdump
1982 nm(1), readelf(1), and the Info entries for @file{binutils}.
1990 @cindex archive contents
1991 @cindex symbol index
1993 @c man title ranlib generate index to archive.
1996 @c man begin SYNOPSIS ranlib
1997 ranlib [@option{-vV}] @var{archive}
2001 @c man begin DESCRIPTION ranlib
2003 @command{ranlib} generates an index to the contents of an archive and
2004 stores it in the archive. The index lists each symbol defined by a
2005 member of an archive that is a relocatable object file.
2007 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2009 An archive with such an index speeds up linking to the library and
2010 allows routines in the library to call each other without regard to
2011 their placement in the archive.
2013 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2014 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2019 @c man begin OPTIONS ranlib
2025 Show the version number of @command{ranlib}.
2031 @c man begin SEEALSO ranlib
2032 ar(1), nm(1), and the Info entries for @file{binutils}.
2040 @cindex section sizes
2042 @c man title size list section sizes and total size.
2045 @c man begin SYNOPSIS size
2046 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2048 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2049 [@option{-t}|@option{--totals}]
2050 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2051 [@var{objfile}@dots{}]
2055 @c man begin DESCRIPTION size
2057 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2058 size---for each of the object or archive files @var{objfile} in its
2059 argument list. By default, one line of output is generated for each
2060 object file or each module in an archive.
2062 @var{objfile}@dots{} are the object files to be examined.
2063 If none are specified, the file @code{a.out} will be used.
2067 @c man begin OPTIONS size
2069 The command line options have the following meanings:
2074 @itemx --format=@var{compatibility}
2075 @cindex @command{size} display format
2076 Using one of these options, you can choose whether the output from @sc{gnu}
2077 @command{size} resembles output from System V @command{size} (using @option{-A},
2078 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2079 @option{--format=berkeley}). The default is the one-line format similar to
2081 @c Bonus for doc-source readers: you can also say --format=strange (or
2082 @c anything else that starts with 's') for sysv, and --format=boring (or
2083 @c anything else that starts with 'b') for Berkeley.
2085 Here is an example of the Berkeley (default) format of output from
2088 $ size --format=Berkeley ranlib size
2089 text data bss dec hex filename
2090 294880 81920 11592 388392 5ed28 ranlib
2091 294880 81920 11888 388688 5ee50 size
2095 This is the same data, but displayed closer to System V conventions:
2098 $ size --format=SysV ranlib size
2116 Show a summary of acceptable arguments and options.
2121 @itemx --radix=@var{number}
2122 @cindex @command{size} number format
2123 @cindex radix for section sizes
2124 Using one of these options, you can control whether the size of each
2125 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2126 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2127 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2128 values (8, 10, 16) are supported. The total size is always given in two
2129 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2130 octal and hexadecimal if you're using @option{-o}.
2134 Show totals of all objects listed (Berkeley format listing mode only).
2136 @item --target=@var{bfdname}
2137 @cindex object code format
2138 Specify that the object-code format for @var{objfile} is
2139 @var{bfdname}. This option may not be necessary; @command{size} can
2140 automatically recognize many formats.
2141 @xref{Target Selection}, for more information.
2145 Display the version number of @command{size}.
2151 @c man begin SEEALSO size
2152 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2159 @cindex listings strings
2160 @cindex printing strings
2161 @cindex strings, printing
2163 @c man title strings print the strings of printable characters in files.
2166 @c man begin SYNOPSIS strings
2167 strings [@option{-afov}] [@option{-}@var{min-len}]
2168 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2169 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2170 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2171 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2172 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2173 [@option{--help}] [@option{--version}] @var{file}@dots{}
2177 @c man begin DESCRIPTION strings
2179 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2180 character sequences that are at least 4 characters long (or the number
2181 given with the options below) and are followed by an unprintable
2182 character. By default, it only prints the strings from the initialized
2183 and loaded sections of object files; for other types of files, it prints
2184 the strings from the whole file.
2186 @command{strings} is mainly useful for determining the contents of non-text
2191 @c man begin OPTIONS strings
2197 Do not scan only the initialized and loaded sections of object files;
2198 scan the whole files.
2201 @itemx --print-file-name
2202 Print the name of the file before each string.
2205 Print a summary of the program usage on the standard output and exit.
2207 @item -@var{min-len}
2208 @itemx -n @var{min-len}
2209 @itemx --bytes=@var{min-len}
2210 Print sequences of characters that are at least @var{min-len} characters
2211 long, instead of the default 4.
2214 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2215 act like @samp{-t d} instead. Since we can not be compatible with both
2216 ways, we simply chose one.
2218 @item -t @var{radix}
2219 @itemx --radix=@var{radix}
2220 Print the offset within the file before each string. The single
2221 character argument specifies the radix of the offset---@samp{o} for
2222 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2224 @item -e @var{encoding}
2225 @itemx --encoding=@var{encoding}
2226 Select the character encoding of the strings that are to be found.
2227 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2228 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2229 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2230 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2231 littleendian. Useful for finding wide character strings.
2233 @item -T @var{bfdname}
2234 @itemx --target=@var{bfdname}
2235 @cindex object code format
2236 Specify an object code format other than your system's default format.
2237 @xref{Target Selection}, for more information.
2241 Print the program version number on the standard output and exit.
2247 @c man begin SEEALSO strings
2248 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2249 and the Info entries for @file{binutils}.
2257 @cindex removing symbols
2258 @cindex discarding symbols
2259 @cindex symbols, discarding
2261 @c man title strip Discard symbols from object files.
2264 @c man begin SYNOPSIS strip
2265 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2266 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2267 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2268 [@option{-s}|@option{--strip-all}]
2269 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2270 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2271 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2272 [@option{-w}|@option{--wildcard}]
2273 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2274 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2275 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2276 [@option{--keep-file-symbols}]
2277 [@option{--only-keep-debug}]
2278 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2279 [@option{--help}] [@option{--info}]
2280 @var{objfile}@dots{}
2284 @c man begin DESCRIPTION strip
2286 @sc{gnu} @command{strip} discards all symbols from object files
2287 @var{objfile}. The list of object files may include archives.
2288 At least one object file must be given.
2290 @command{strip} modifies the files named in its argument,
2291 rather than writing modified copies under different names.
2295 @c man begin OPTIONS strip
2298 @item -F @var{bfdname}
2299 @itemx --target=@var{bfdname}
2300 Treat the original @var{objfile} as a file with the object
2301 code format @var{bfdname}, and rewrite it in the same format.
2302 @xref{Target Selection}, for more information.
2305 Show a summary of the options to @command{strip} and exit.
2308 Display a list showing all architectures and object formats available.
2310 @item -I @var{bfdname}
2311 @itemx --input-target=@var{bfdname}
2312 Treat the original @var{objfile} as a file with the object
2313 code format @var{bfdname}.
2314 @xref{Target Selection}, for more information.
2316 @item -O @var{bfdname}
2317 @itemx --output-target=@var{bfdname}
2318 Replace @var{objfile} with a file in the output format @var{bfdname}.
2319 @xref{Target Selection}, for more information.
2321 @item -R @var{sectionname}
2322 @itemx --remove-section=@var{sectionname}
2323 Remove any section named @var{sectionname} from the output file. This
2324 option may be given more than once. Note that using this option
2325 inappropriately may make the output file unusable.
2334 @itemx --strip-debug
2335 Remove debugging symbols only.
2337 @item --strip-unneeded
2338 Remove all symbols that are not needed for relocation processing.
2340 @item -K @var{symbolname}
2341 @itemx --keep-symbol=@var{symbolname}
2342 When stripping symbols, keep symbol @var{symbolname} even if it would
2343 normally be stripped. This option may be given more than once.
2345 @item -N @var{symbolname}
2346 @itemx --strip-symbol=@var{symbolname}
2347 Remove symbol @var{symbolname} from the source file. This option may be
2348 given more than once, and may be combined with strip options other than
2352 Put the stripped output in @var{file}, rather than replacing the
2353 existing file. When this argument is used, only one @var{objfile}
2354 argument may be specified.
2357 @itemx --preserve-dates
2358 Preserve the access and modification dates of the file.
2362 Permit regular expressions in @var{symbolname}s used in other command
2363 line options. The question mark (?), asterisk (*), backslash (\) and
2364 square brackets ([]) operators can be used anywhere in the symbol
2365 name. If the first character of the symbol name is the exclamation
2366 point (!) then the sense of the switch is reversed for that symbol.
2373 would cause strip to only keep symbols that start with the letters
2374 ``fo'', but to discard the symbol ``foo''.
2377 @itemx --discard-all
2378 Remove non-global symbols.
2381 @itemx --discard-locals
2382 Remove compiler-generated local symbols.
2383 (These usually start with @samp{L} or @samp{.}.)
2385 @item --keep-file-symbols
2386 When stripping a file, perhaps with @option{--strip-debug} or
2387 @option{--strip-unneeded}, retain any symbols specifying source file names,
2388 which would otherwise get stripped.
2390 @item --only-keep-debug
2391 Strip a file, removing any sections that would be stripped by
2392 @option{--strip-debug} and leaving the debugging sections.
2394 The intention is that this option will be used in conjunction with
2395 @option{--add-gnu-debuglink} to create a two part executable. One a
2396 stripped binary which will occupy less space in RAM and in a
2397 distribution and the second a debugging information file which is only
2398 needed if debugging abilities are required. The suggested procedure
2399 to create these files is as follows:
2402 @item Link the executable as normal. Assuming that is is called
2404 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2405 create a file containing the debugging info.
2406 @item Run @code{objcopy --strip-debug foo} to create a
2407 stripped executable.
2408 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2409 to add a link to the debugging info into the stripped executable.
2412 Note - the choice of @code{.dbg} as an extension for the debug info
2413 file is arbitrary. Also the @code{--only-keep-debug} step is
2414 optional. You could instead do this:
2417 @item Link the executable as normal.
2418 @item Copy @code{foo} to @code{foo.full}
2419 @item Run @code{strip --strip-debug foo}
2420 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2423 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2424 full executable. It does not have to be a file created by the
2425 @option{--only-keep-debug} switch.
2427 Note - this switch is only intended for use on fully linked files. It
2428 does not make sense to use it on object files where the debugging
2429 information may be incomplete. Besides the gnu_debuglink feature
2430 currently only supports the presence of one filename containing
2431 debugging information, not multiple filenames on a one-per-object-file
2436 Show the version number for @command{strip}.
2440 Verbose output: list all object files modified. In the case of
2441 archives, @samp{strip -v} lists all members of the archive.
2447 @c man begin SEEALSO strip
2448 the Info entries for @file{binutils}.
2452 @node c++filt, addr2line, strip, Top
2456 @cindex demangling C++ symbols
2458 @c man title cxxfilt Demangle C++ and Java symbols.
2461 @c man begin SYNOPSIS cxxfilt
2462 c++filt [@option{-_}|@option{--strip-underscores}]
2463 [@option{-n}|@option{--no-strip-underscores}]
2464 [@option{-p}|@option{--no-params}]
2465 [@option{-t}|@option{--types}]
2466 [@option{-i}|@option{--no-verbose}]
2467 [@option{-s} @var{format}|@option{--format=}@var{format}]
2468 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2472 @c man begin DESCRIPTION cxxfilt
2475 The C++ and Java languages provide function overloading, which means
2476 that you can write many functions with the same name, providing that
2477 each function takes parameters of different types. In order to be
2478 able to distinguish these similarly named functions C++ and Java
2479 encode them into a low-level assembler name which uniquely identifies
2480 each different version. This process is known as @dfn{mangling}. The
2482 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2483 MS-DOS this program is named @command{CXXFILT}.}
2484 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2485 names into user-level names so that they can be read.
2487 Every alphanumeric word (consisting of letters, digits, underscores,
2488 dollars, or periods) seen in the input is a potential mangled name.
2489 If the name decodes into a C++ name, the C++ name replaces the
2490 low-level name in the output, otherwise the original word is output.
2491 In this way you can pass an entire assembler source file, containing
2492 mangled names, through @command{c++filt} and see the same source file
2493 containing demangled names.
2495 You can also use @command{c++filt} to decipher individual symbols by
2496 passing them on the command line:
2499 c++filt @var{symbol}
2502 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2503 names from the standard input instead. All the results are printed on
2504 the standard output. The difference between reading names from the
2505 command line versus reading names from the standard input is that
2506 command line arguments are expected to be just mangled names and no
2507 checking is performed to separate them from surrounding text. Thus
2514 will work and demangle the name to ``f()'' whereas:
2520 will not work. (Note the extra comma at the end of the mangled
2521 name which makes it invalid). This command however will work:
2524 echo _Z1fv, | c++filt -n
2527 and will display ``f(),'' ie the demangled name followed by a
2528 trailing comma. This behaviour is because when the names are read
2529 from the standard input it is expected that they might be part of an
2530 assembler source file where there might be extra, extraneous
2531 characters trailing after a mangled name. eg:
2534 .type _Z1fv, @@function
2539 @c man begin OPTIONS cxxfilt
2543 @itemx --strip-underscores
2544 On some systems, both the C and C++ compilers put an underscore in front
2545 of every name. For example, the C name @code{foo} gets the low-level
2546 name @code{_foo}. This option removes the initial underscore. Whether
2547 @command{c++filt} removes the underscore by default is target dependent.
2551 Prints demangled names using Java syntax. The default is to use C++
2555 @itemx --no-strip-underscores
2556 Do not remove the initial underscore.
2560 When demangling the name of a function, do not display the types of
2561 the function's parameters.
2565 Attempt to demangle types as well as function names. This is disabled
2566 by default since mangled types are normally only used internally in
2567 the compiler, and they can be confused with non-mangled names. eg
2568 a function called ``a'' treated as a mangled type name would be
2569 demangled to ``signed char''.
2573 Do not include implementation details (if any) in the demangled
2576 @item -s @var{format}
2577 @itemx --format=@var{format}
2578 @command{c++filt} can decode various methods of mangling, used by
2579 different compilers. The argument to this option selects which
2584 Automatic selection based on executable (the default method)
2586 the one used by the @sc{gnu} C++ compiler (g++)
2588 the one used by the Lucid compiler (lcc)
2590 the one specified by the C++ Annotated Reference Manual
2592 the one used by the HP compiler (aCC)
2594 the one used by the EDG compiler
2596 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2598 the one used by the @sc{gnu} Java compiler (gcj)
2600 the one used by the @sc{gnu} Ada compiler (GNAT).
2604 Print a summary of the options to @command{c++filt} and exit.
2607 Print the version number of @command{c++filt} and exit.
2613 @c man begin SEEALSO cxxfilt
2614 the Info entries for @file{binutils}.
2619 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2620 user interface are subject to change in future releases. In particular,
2621 a command-line option may be required in the future to decode a name
2622 passed as an argument on the command line; in other words,
2625 c++filt @var{symbol}
2629 may in a future release become
2632 c++filt @var{option} @var{symbol}
2640 @cindex address to file name and line number
2642 @c man title addr2line convert addresses into file names and line numbers.
2645 @c man begin SYNOPSIS addr2line
2646 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2647 [@option{-C}|@option{--demangle}[=@var{style}]]
2648 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2649 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2650 [@option{-i}|@option{--inlines}]
2651 [@option{-j}|@option{--section=}@var{name}]
2652 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2657 @c man begin DESCRIPTION addr2line
2659 @command{addr2line} translates addresses into file names and line numbers.
2660 Given an address in an executable or an offset in a section of a relocatable
2661 object, it uses the debugging information to figure out which file name and
2662 line number are associated with it.
2664 The executable or relocatable object to use is specified with the @option{-e}
2665 option. The default is the file @file{a.out}. The section in the relocatable
2666 object to use is specified with the @option{-j} option.
2668 @command{addr2line} has two modes of operation.
2670 In the first, hexadecimal addresses are specified on the command line,
2671 and @command{addr2line} displays the file name and line number for each
2674 In the second, @command{addr2line} reads hexadecimal addresses from
2675 standard input, and prints the file name and line number for each
2676 address on standard output. In this mode, @command{addr2line} may be used
2677 in a pipe to convert dynamically chosen addresses.
2679 The format of the output is @samp{FILENAME:LINENO}. The file name and
2680 line number for each address is printed on a separate line. If the
2681 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2682 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2683 containing the address.
2685 If the file name or function name can not be determined,
2686 @command{addr2line} will print two question marks in their place. If the
2687 line number can not be determined, @command{addr2line} will print 0.
2691 @c man begin OPTIONS addr2line
2693 The long and short forms of options, shown here as alternatives, are
2697 @item -b @var{bfdname}
2698 @itemx --target=@var{bfdname}
2699 @cindex object code format
2700 Specify that the object-code format for the object files is
2704 @itemx --demangle[=@var{style}]
2705 @cindex demangling in objdump
2706 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2707 Besides removing any initial underscore prepended by the system, this
2708 makes C++ function names readable. Different compilers have different
2709 mangling styles. The optional demangling style argument can be used to
2710 choose an appropriate demangling style for your compiler. @xref{c++filt},
2711 for more information on demangling.
2713 @item -e @var{filename}
2714 @itemx --exe=@var{filename}
2715 Specify the name of the executable for which addresses should be
2716 translated. The default file is @file{a.out}.
2720 Display function names as well as file and line number information.
2724 Display only the base of each file name.
2728 If the address belongs to a function that was inlined, the source
2729 information for all enclosing scopes back to the first non-inlined
2730 function will also be printed. For example, if @code{main} inlines
2731 @code{callee1} which inlines @code{callee2}, and address is from
2732 @code{callee2}, the source information for @code{callee1} and @code{main}
2733 will also be printed.
2737 Read offsets relative to the specified section instead of absolute addresses.
2743 @c man begin SEEALSO addr2line
2744 Info entries for @file{binutils}.
2751 @command{nlmconv} converts a relocatable object file into a NetWare
2755 @command{nlmconv} currently works with @samp{i386} object
2756 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2757 object files in @sc{elf}, or @code{a.out} format@footnote{
2758 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2759 format in the Binary File Descriptor library. It has only been tested
2760 with the above formats.}.
2764 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2765 utilities, since it is only useful for NLM targets.
2768 @c man title nlmconv converts object code into an NLM.
2771 @c man begin SYNOPSIS nlmconv
2772 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2773 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2774 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2775 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2776 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2777 @var{infile} @var{outfile}
2781 @c man begin DESCRIPTION nlmconv
2783 @command{nlmconv} converts the relocatable @samp{i386} object file
2784 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2785 reading @var{headerfile} for NLM header information. For instructions
2786 on writing the NLM command file language used in header files, see the
2787 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2788 Development and Tools Overview}, which is part of the NLM Software
2789 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2790 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2793 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2796 @command{nlmconv} can perform a link step. In other words, you can list
2797 more than one object file for input if you list them in the definitions
2798 file (rather than simply specifying one input file on the command line).
2799 In this case, @command{nlmconv} calls the linker for you.
2803 @c man begin OPTIONS nlmconv
2806 @item -I @var{bfdname}
2807 @itemx --input-target=@var{bfdname}
2808 Object format of the input file. @command{nlmconv} can usually determine
2809 the format of a given file (so no default is necessary).
2810 @xref{Target Selection}, for more information.
2812 @item -O @var{bfdname}
2813 @itemx --output-target=@var{bfdname}
2814 Object format of the output file. @command{nlmconv} infers the output
2815 format based on the input format, e.g. for a @samp{i386} input file the
2816 output format is @samp{nlm32-i386}.
2817 @xref{Target Selection}, for more information.
2819 @item -T @var{headerfile}
2820 @itemx --header-file=@var{headerfile}
2821 Reads @var{headerfile} for NLM header information. For instructions on
2822 writing the NLM command file language used in header files, see@ see the
2823 @samp{linkers} section, of the @cite{NLM Development and Tools
2824 Overview}, which is part of the NLM Software Developer's Kit, available
2829 Displays (on standard error) the linker command line used by @command{nlmconv}.
2831 @item -l @var{linker}
2832 @itemx --linker=@var{linker}
2833 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2838 Prints a usage summary.
2842 Prints the version number for @command{nlmconv}.
2848 @c man begin SEEALSO nlmconv
2849 the Info entries for @file{binutils}.
2856 @command{windres} may be used to manipulate Windows resources.
2859 @emph{Warning:} @command{windres} is not always built as part of the binary
2860 utilities, since it is only useful for Windows targets.
2863 @c man title windres manipulate Windows resources.
2866 @c man begin SYNOPSIS windres
2867 windres [options] [input-file] [output-file]
2871 @c man begin DESCRIPTION windres
2873 @command{windres} reads resources from an input file and copies them into
2874 an output file. Either file may be in one of three formats:
2878 A text format read by the Resource Compiler.
2881 A binary format generated by the Resource Compiler.
2884 A COFF object or executable.
2887 The exact description of these different formats is available in
2888 documentation from Microsoft.
2890 When @command{windres} converts from the @code{rc} format to the @code{res}
2891 format, it is acting like the Windows Resource Compiler. When
2892 @command{windres} converts from the @code{res} format to the @code{coff}
2893 format, it is acting like the Windows @code{CVTRES} program.
2895 When @command{windres} generates an @code{rc} file, the output is similar
2896 but not identical to the format expected for the input. When an input
2897 @code{rc} file refers to an external filename, an output @code{rc} file
2898 will instead include the file contents.
2900 If the input or output format is not specified, @command{windres} will
2901 guess based on the file name, or, for the input file, the file contents.
2902 A file with an extension of @file{.rc} will be treated as an @code{rc}
2903 file, a file with an extension of @file{.res} will be treated as a
2904 @code{res} file, and a file with an extension of @file{.o} or
2905 @file{.exe} will be treated as a @code{coff} file.
2907 If no output file is specified, @command{windres} will print the resources
2908 in @code{rc} format to standard output.
2910 The normal use is for you to write an @code{rc} file, use @command{windres}
2911 to convert it to a COFF object file, and then link the COFF file into
2912 your application. This will make the resources described in the
2913 @code{rc} file available to Windows.
2917 @c man begin OPTIONS windres
2920 @item -i @var{filename}
2921 @itemx --input @var{filename}
2922 The name of the input file. If this option is not used, then
2923 @command{windres} will use the first non-option argument as the input file
2924 name. If there are no non-option arguments, then @command{windres} will
2925 read from standard input. @command{windres} can not read a COFF file from
2928 @item -o @var{filename}
2929 @itemx --output @var{filename}
2930 The name of the output file. If this option is not used, then
2931 @command{windres} will use the first non-option argument, after any used
2932 for the input file name, as the output file name. If there is no
2933 non-option argument, then @command{windres} will write to standard output.
2934 @command{windres} can not write a COFF file to standard output. Note,
2935 for compatibility with @command{rc} the option @option{-fo} is also
2936 accepted, but its use is not recommended.
2938 @item -J @var{format}
2939 @itemx --input-format @var{format}
2940 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2941 @samp{coff}. If no input format is specified, @command{windres} will
2942 guess, as described above.
2944 @item -O @var{format}
2945 @itemx --output-format @var{format}
2946 The output format to generate. @var{format} may be @samp{res},
2947 @samp{rc}, or @samp{coff}. If no output format is specified,
2948 @command{windres} will guess, as described above.
2950 @item -F @var{target}
2951 @itemx --target @var{target}
2952 Specify the BFD format to use for a COFF file as input or output. This
2953 is a BFD target name; you can use the @option{--help} option to see a list
2954 of supported targets. Normally @command{windres} will use the default
2955 format, which is the first one listed by the @option{--help} option.
2957 @ref{Target Selection}.
2960 @item --preprocessor @var{program}
2961 When @command{windres} reads an @code{rc} file, it runs it through the C
2962 preprocessor first. This option may be used to specify the preprocessor
2963 to use, including any leading arguments. The default preprocessor
2964 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2966 @item -I @var{directory}
2967 @itemx --include-dir @var{directory}
2968 Specify an include directory to use when reading an @code{rc} file.
2969 @command{windres} will pass this to the preprocessor as an @option{-I}
2970 option. @command{windres} will also search this directory when looking for
2971 files named in the @code{rc} file. If the argument passed to this command
2972 matches any of the supported @var{formats} (as described in the @option{-J}
2973 option), it will issue a deprecation warning, and behave just like the
2974 @option{-J} option. New programs should not use this behaviour. If a
2975 directory happens to match a @var{format}, simple prefix it with @samp{./}
2976 to disable the backward compatibility.
2978 @item -D @var{target}
2979 @itemx --define @var{sym}[=@var{val}]
2980 Specify a @option{-D} option to pass to the preprocessor when reading an
2983 @item -U @var{target}
2984 @itemx --undefine @var{sym}
2985 Specify a @option{-U} option to pass to the preprocessor when reading an
2989 Ignored for compatibility with rc.
2992 Enable verbose mode. This tells you what the preprocessor is if you
2996 @item --language @var{val}
2997 Specify the default language to use when reading an @code{rc} file.
2998 @var{val} should be a hexadecimal language code. The low eight bits are
2999 the language, and the high eight bits are the sublanguage.
3001 @item --use-temp-file
3002 Use a temporary file to instead of using popen to read the output of
3003 the preprocessor. Use this option if the popen implementation is buggy
3004 on the host (eg., certain non-English language versions of Windows 95 and
3005 Windows 98 are known to have buggy popen where the output will instead
3008 @item --no-use-temp-file
3009 Use popen, not a temporary file, to read the output of the preprocessor.
3010 This is the default behaviour.
3014 Prints a usage summary.
3018 Prints the version number for @command{windres}.
3021 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3022 this will turn on parser debugging.
3028 @c man begin SEEALSO windres
3029 the Info entries for @file{binutils}.
3038 @command{dlltool} is used to create the files needed to create dynamic
3039 link libraries (DLLs) on systems which understand PE format image
3040 files such as Windows. A DLL contains an export table which contains
3041 information that the runtime loader needs to resolve references from a
3042 referencing program.
3044 The export table is generated by this program by reading in a
3045 @file{.def} file or scanning the @file{.a} and @file{.o} files which
3046 will be in the DLL. A @file{.o} file can contain information in
3047 special @samp{.drectve} sections with export information.
3050 @emph{Note:} @command{dlltool} is not always built as part of the
3051 binary utilities, since it is only useful for those targets which
3055 @c man title dlltool Create files needed to build and use DLLs.
3058 @c man begin SYNOPSIS dlltool
3059 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3060 [@option{-b}|@option{--base-file} @var{base-file-name}]
3061 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3062 [@option{-z}|@option{--output-def} @var{def-file-name}]
3063 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3064 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3065 [@option{--exclude-symbols} @var{list}]
3066 [@option{--no-default-excludes}]
3067 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3068 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3069 [@option{-a}|@option{--add-indirect}]
3070 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3071 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3072 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3073 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
3074 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3075 [@option{-v}|@option{--verbose}]
3076 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3077 [object-file @dots{}]
3081 @c man begin DESCRIPTION dlltool
3083 @command{dlltool} reads its inputs, which can come from the @option{-d} and
3084 @option{-b} options as well as object files specified on the command
3085 line. It then processes these inputs and if the @option{-e} option has
3086 been specified it creates a exports file. If the @option{-l} option
3087 has been specified it creates a library file and if the @option{-z} option
3088 has been specified it creates a def file. Any or all of the @option{-e},
3089 @option{-l} and @option{-z} options can be present in one invocation of
3092 When creating a DLL, along with the source for the DLL, it is necessary
3093 to have three other files. @command{dlltool} can help with the creation of
3096 The first file is a @file{.def} file which specifies which functions are
3097 exported from the DLL, which functions the DLL imports, and so on. This
3098 is a text file and can be created by hand, or @command{dlltool} can be used
3099 to create it using the @option{-z} option. In this case @command{dlltool}
3100 will scan the object files specified on its command line looking for
3101 those functions which have been specially marked as being exported and
3102 put entries for them in the @file{.def} file it creates.
3104 In order to mark a function as being exported from a DLL, it needs to
3105 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
3106 section of the object file. This can be done in C by using the
3110 asm (".section .drectve");
3111 asm (".ascii \"-export:my_func\"");
3113 int my_func (void) @{ @dots{} @}
3116 The second file needed for DLL creation is an exports file. This file
3117 is linked with the object files that make up the body of the DLL and it
3118 handles the interface between the DLL and the outside world. This is a
3119 binary file and it can be created by giving the @option{-e} option to
3120 @command{dlltool} when it is creating or reading in a @file{.def} file.
3122 The third file needed for DLL creation is the library file that programs
3123 will link with in order to access the functions in the DLL. This file
3124 can be created by giving the @option{-l} option to dlltool when it
3125 is creating or reading in a @file{.def} file.
3127 @command{dlltool} builds the library file by hand, but it builds the
3128 exports file by creating temporary files containing assembler statements
3129 and then assembling these. The @option{-S} command line option can be
3130 used to specify the path to the assembler that dlltool will use,
3131 and the @option{-f} option can be used to pass specific flags to that
3132 assembler. The @option{-n} can be used to prevent dlltool from deleting
3133 these temporary assembler files when it is done, and if @option{-n} is
3134 specified twice then this will prevent dlltool from deleting the
3135 temporary object files it used to build the library.
3137 Here is an example of creating a DLL from a source file @samp{dll.c} and
3138 also creating a program (from an object file called @samp{program.o})
3143 dlltool -e exports.o -l dll.lib dll.o
3144 gcc dll.o exports.o -o dll.dll
3145 gcc program.o dll.lib -o program
3150 @c man begin OPTIONS dlltool
3152 The command line options have the following meanings:
3156 @item -d @var{filename}
3157 @itemx --input-def @var{filename}
3158 @cindex input .def file
3159 Specifies the name of a @file{.def} file to be read in and processed.
3161 @item -b @var{filename}
3162 @itemx --base-file @var{filename}
3164 Specifies the name of a base file to be read in and processed. The
3165 contents of this file will be added to the relocation section in the
3166 exports file generated by dlltool.
3168 @item -e @var{filename}
3169 @itemx --output-exp @var{filename}
3170 Specifies the name of the export file to be created by dlltool.
3172 @item -z @var{filename}
3173 @itemx --output-def @var{filename}
3174 Specifies the name of the @file{.def} file to be created by dlltool.
3176 @item -l @var{filename}
3177 @itemx --output-lib @var{filename}
3178 Specifies the name of the library file to be created by dlltool.
3180 @item --export-all-symbols
3181 Treat all global and weak defined symbols found in the input object
3182 files as symbols to be exported. There is a small list of symbols which
3183 are not exported by default; see the @option{--no-default-excludes}
3184 option. You may add to the list of symbols to not export by using the
3185 @option{--exclude-symbols} option.
3187 @item --no-export-all-symbols
3188 Only export symbols explicitly listed in an input @file{.def} file or in
3189 @samp{.drectve} sections in the input object files. This is the default
3190 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3191 attributes in the source code.
3193 @item --exclude-symbols @var{list}
3194 Do not export the symbols in @var{list}. This is a list of symbol names
3195 separated by comma or colon characters. The symbol names should not
3196 contain a leading underscore. This is only meaningful when
3197 @option{--export-all-symbols} is used.
3199 @item --no-default-excludes
3200 When @option{--export-all-symbols} is used, it will by default avoid
3201 exporting certain special symbols. The current list of symbols to avoid
3202 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3203 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3204 to go ahead and export these special symbols. This is only meaningful
3205 when @option{--export-all-symbols} is used.
3208 @itemx --as @var{path}
3209 Specifies the path, including the filename, of the assembler to be used
3210 to create the exports file.
3212 @item -f @var{options}
3213 @itemx --as-flags @var{options}
3214 Specifies any specific command line options to be passed to the
3215 assembler when building the exports file. This option will work even if
3216 the @option{-S} option is not used. This option only takes one argument,
3217 and if it occurs more than once on the command line, then later
3218 occurrences will override earlier occurrences. So if it is necessary to
3219 pass multiple options to the assembler they should be enclosed in
3223 @itemx --dll-name @var{name}
3224 Specifies the name to be stored in the @file{.def} file as the name of
3225 the DLL when the @option{-e} option is used. If this option is not
3226 present, then the filename given to the @option{-e} option will be
3227 used as the name of the DLL.
3229 @item -m @var{machine}
3230 @itemx -machine @var{machine}
3231 Specifies the type of machine for which the library file should be
3232 built. @command{dlltool} has a built in default type, depending upon how
3233 it was created, but this option can be used to override that. This is
3234 normally only useful when creating DLLs for an ARM processor, when the
3235 contents of the DLL are actually encode using Thumb instructions.
3238 @itemx --add-indirect
3239 Specifies that when @command{dlltool} is creating the exports file it
3240 should add a section which allows the exported functions to be
3241 referenced without using the import library. Whatever the hell that
3245 @itemx --add-underscore
3246 Specifies that when @command{dlltool} is creating the exports file it
3247 should prepend an underscore to the names of @emph{all} exported symbols.
3249 @item --add-stdcall-underscore
3250 Specifies that when @command{dlltool} is creating the exports file it
3251 should prepend an underscore to the names of exported @emph{stdcall}
3252 functions. Variable names and non-stdcall function names are not modified.
3253 This option is useful when creating GNU-compatible import libs for third
3254 party DLLs that were built with MS-Windows tools.
3258 Specifies that when @command{dlltool} is creating the exports file it
3259 should not append the string @samp{@@ <number>}. These numbers are
3260 called ordinal numbers and they represent another way of accessing the
3261 function in a DLL, other than by name.
3264 @itemx --add-stdcall-alias
3265 Specifies that when @command{dlltool} is creating the exports file it
3266 should add aliases for stdcall symbols without @samp{@@ <number>}
3267 in addition to the symbols with @samp{@@ <number>}.
3270 @itemx --ext-prefix-alias @var{prefix}
3271 Causes @command{dlltool} to create external aliases for all DLL
3272 imports with the specified prefix. The aliases are created for both
3273 external and import symbols with no leading underscore.
3277 Specifies that when @command{dlltool} is creating the exports and library
3278 files it should omit the @code{.idata4} section. This is for compatibility
3279 with certain operating systems.
3283 Specifies that when @command{dlltool} is creating the exports and library
3284 files it should omit the @code{.idata5} section. This is for compatibility
3285 with certain operating systems.
3289 Specifies that @command{dlltool} should mark the objects in the library
3290 file and exports file that it produces as supporting interworking
3291 between ARM and Thumb code.
3295 Makes @command{dlltool} preserve the temporary assembler files it used to
3296 create the exports file. If this option is repeated then dlltool will
3297 also preserve the temporary object files it uses to create the library
3300 @item -t @var{prefix}
3301 @itemx --temp-prefix @var{prefix}
3302 Makes @command{dlltool} use @var{prefix} when constructing the names of
3303 temporary assembler and object files. By default, the temp file prefix
3304 is generated from the pid.
3308 Make dlltool describe what it is doing.
3312 Displays a list of command line options and then exits.
3316 Displays dlltool's version number and then exits.
3323 * def file format:: The format of the dlltool @file{.def} file
3326 @node def file format
3327 @section The format of the @command{dlltool} @file{.def} file
3329 A @file{.def} file contains any number of the following commands:
3333 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
3334 The result is going to be named @var{name}@code{.exe}.
3336 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
3337 The result is going to be named @var{name}@code{.dll}.
3339 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )}
3340 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
3341 Declares @var{name1} as an exported symbol from the DLL, with optional
3342 ordinal number @var{integer}, or declares @var{name1} as an alias
3343 (forward) of the function @var{external-name} in the DLL
3346 @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{) ) *}
3347 Declares that @var{external-name} or the exported function whose
3348 ordinal number is @var{integer} is to be imported from the file
3349 @var{module-name}. If @var{internal-name} is specified then this is
3350 the name that the imported function will be referred to in the body of
3353 @item @code{DESCRIPTION} @var{string}
3354 Puts @var{string} into the output @file{.exp} file in the
3355 @code{.rdata} section.
3357 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3358 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3359 Generates @code{--stack} or @code{--heap}
3360 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
3361 section. The linker will see this and act upon it.
3363 @item @code{CODE} @var{attr} @code{+}
3364 @item @code{DATA} @var{attr} @code{+}
3365 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
3366 Generates @code{--attr} @var{section-name} @var{attr} in the output
3367 @code{.drectve} section, where @var{attr} is one of @code{READ},
3368 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
3369 this and act upon it.
3374 @c man begin SEEALSO dlltool
3375 The Info pages for @file{binutils}.
3382 @cindex ELF file information
3385 @c man title readelf Displays information about ELF files.
3388 @c man begin SYNOPSIS readelf
3389 readelf [@option{-a}|@option{--all}]
3390 [@option{-h}|@option{--file-header}]
3391 [@option{-l}|@option{--program-headers}|@option{--segments}]
3392 [@option{-S}|@option{--section-headers}|@option{--sections}]
3393 [@option{-g}|@option{--section-groups}]
3394 [@option{-t}|@option{--section-details}]
3395 [@option{-e}|@option{--headers}]
3396 [@option{-s}|@option{--syms}|@option{--symbols}]
3397 [@option{-n}|@option{--notes}]
3398 [@option{-r}|@option{--relocs}]
3399 [@option{-u}|@option{--unwind}]
3400 [@option{-d}|@option{--dynamic}]
3401 [@option{-V}|@option{--version-info}]
3402 [@option{-A}|@option{--arch-specific}]
3403 [@option{-D}|@option{--use-dynamic}]
3404 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
3405 [@option{-w[liaprmfFsoR]}|
3406 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
3407 [@option{-I}|@option{-histogram}]
3408 [@option{-v}|@option{--version}]
3409 [@option{-W}|@option{--wide}]
3410 [@option{-H}|@option{--help}]
3411 @var{elffile}@dots{}
3415 @c man begin DESCRIPTION readelf
3417 @command{readelf} displays information about one or more ELF format object
3418 files. The options control what particular information to display.
3420 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3421 64-bit ELF files are supported, as are archives containing ELF files.
3423 This program performs a similar function to @command{objdump} but it
3424 goes into more detail and it exists independently of the @sc{bfd}
3425 library, so if there is a bug in @sc{bfd} then readelf will not be
3430 @c man begin OPTIONS readelf
3432 The long and short forms of options, shown here as alternatives, are
3433 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3439 Equivalent to specifying @option{--file-header},
3440 @option{--program-headers}, @option{--sections}, @option{--symbols},
3441 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3442 @option{--version-info}.
3445 @itemx --file-header
3446 @cindex ELF file header information
3447 Displays the information contained in the ELF header at the start of the
3451 @itemx --program-headers
3453 @cindex ELF program header information
3454 @cindex ELF segment information
3455 Displays the information contained in the file's segment headers, if it
3460 @itemx --section-headers
3461 @cindex ELF section information
3462 Displays the information contained in the file's section headers, if it
3466 @itemx --section-groups
3467 @cindex ELF section group information
3468 Displays the information contained in the file's section groups, if it
3472 @itemx --section-details
3473 @cindex ELF section information
3474 Displays the detailed section information. Implies @option{-S}.
3479 @cindex ELF symbol table information
3480 Displays the entries in symbol table section of the file, if it has one.
3484 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3489 Displays the contents of the NOTE segments and/or sections, if any.
3493 @cindex ELF reloc information
3494 Displays the contents of the file's relocation section, if it has one.
3498 @cindex unwind information
3499 Displays the contents of the file's unwind section, if it has one. Only
3500 the unwind sections for IA64 ELF files are currently supported.
3504 @cindex ELF dynamic section information
3505 Displays the contents of the file's dynamic section, if it has one.
3508 @itemx --version-info
3509 @cindex ELF version sections informations
3510 Displays the contents of the version sections in the file, it they
3514 @itemx --arch-specific
3515 Displays architecture-specific information in the file, if there
3519 @itemx --use-dynamic
3520 When displaying symbols, this option makes @command{readelf} use the
3521 symbol table in the file's dynamic section, rather than the one in the
3524 @item -x <number or name>
3525 @itemx --hex-dump=<number or name>
3526 Displays the contents of the indicated section as a hexadecimal dump.
3527 A number identifies a particular section by index in the section table;
3528 any other string identifies all sections with that name in the object file.
3530 @item -w[liaprmfFsoR]
3531 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
3532 Displays the contents of the debug sections in the file, if any are
3533 present. If one of the optional letters or words follows the switch
3534 then only data found in those specific sections will be dumped.
3538 Display a histogram of bucket list lengths when displaying the contents
3539 of the symbol tables.
3543 Display the version number of readelf.
3547 Don't break output lines to fit into 80 columns. By default
3548 @command{readelf} breaks section header and segment listing lines for
3549 64-bit ELF files, so that they fit into 80 columns. This option causes
3550 @command{readelf} to print each section header resp. each segment one a
3551 single line, which is far more readable on terminals wider than 80 columns.
3555 Display the command line options understood by @command{readelf}.
3562 @c man begin SEEALSO readelf
3563 objdump(1), and the Info entries for @file{binutils}.
3567 @node Common Options
3568 @chapter Common Options
3570 The following command-line options are supported by all of the
3571 programs described in this manual.
3573 @c man begin OPTIONS
3575 @include at-file.texi
3579 Display the command-line options supported by the program.
3582 Display the version number of the program.
3584 @c man begin OPTIONS
3588 @node Selecting The Target System
3589 @chapter Selecting the Target System
3591 You can specify two aspects of the target system to the @sc{gnu}
3592 binary file utilities, each in several ways:
3602 In the following summaries, the lists of ways to specify values are in
3603 order of decreasing precedence. The ways listed first override those
3606 The commands to list valid values only list the values for which the
3607 programs you are running were configured. If they were configured with
3608 @option{--enable-targets=all}, the commands list most of the available
3609 values, but a few are left out; not all targets can be configured in at
3610 once because some of them can only be configured @dfn{native} (on hosts
3611 with the same type as the target system).
3614 * Target Selection::
3615 * Architecture Selection::
3618 @node Target Selection
3619 @section Target Selection
3621 A @dfn{target} is an object file format. A given target may be
3622 supported for multiple architectures (@pxref{Architecture Selection}).
3623 A target selection may also have variations for different operating
3624 systems or architectures.
3626 The command to list valid target values is @samp{objdump -i}
3627 (the first column of output contains the relevant information).
3629 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3630 @samp{a.out-sunos-big}.
3632 You can also specify a target using a configuration triplet. This is
3633 the same sort of name that is passed to @file{configure} to specify a
3634 target. When you use a configuration triplet as an argument, it must be
3635 fully canonicalized. You can see the canonical version of a triplet by
3636 running the shell script @file{config.sub} which is included with the
3639 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3640 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3642 @subheading @command{objdump} Target
3648 command line option: @option{-b} or @option{--target}
3651 environment variable @code{GNUTARGET}
3654 deduced from the input file
3657 @subheading @command{objcopy} and @command{strip} Input Target
3663 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3666 environment variable @code{GNUTARGET}
3669 deduced from the input file
3672 @subheading @command{objcopy} and @command{strip} Output Target
3678 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3681 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3684 environment variable @code{GNUTARGET}
3687 deduced from the input file
3690 @subheading @command{nm}, @command{size}, and @command{strings} Target
3696 command line option: @option{--target}
3699 environment variable @code{GNUTARGET}
3702 deduced from the input file
3705 @node Architecture Selection
3706 @section Architecture Selection
3708 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3709 to run. Its name may contain a colon, separating the name of the
3710 processor family from the name of the particular @sc{cpu}.
3712 The command to list valid architecture values is @samp{objdump -i} (the
3713 second column contains the relevant information).
3715 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3717 @subheading @command{objdump} Architecture
3723 command line option: @option{-m} or @option{--architecture}
3726 deduced from the input file
3729 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3735 deduced from the input file
3738 @node Reporting Bugs
3739 @chapter Reporting Bugs
3741 @cindex reporting bugs
3743 Your bug reports play an essential role in making the binary utilities
3746 Reporting a bug may help you by bringing a solution to your problem, or
3747 it may not. But in any case the principal function of a bug report is
3748 to help the entire community by making the next version of the binary
3749 utilities work better. Bug reports are your contribution to their
3752 In order for a bug report to serve its purpose, you must include the
3753 information that enables us to fix the bug.
3756 * Bug Criteria:: Have you found a bug?
3757 * Bug Reporting:: How to report bugs
3761 @section Have You Found a Bug?
3762 @cindex bug criteria
3764 If you are not sure whether you have found a bug, here are some guidelines:
3767 @cindex fatal signal
3770 If a binary utility gets a fatal signal, for any input whatever, that is
3771 a bug. Reliable utilities never crash.
3773 @cindex error on valid input
3775 If a binary utility produces an error message for valid input, that is a
3779 If you are an experienced user of binary utilities, your suggestions for
3780 improvement are welcome in any case.
3784 @section How to Report Bugs
3786 @cindex bugs, reporting
3788 A number of companies and individuals offer support for @sc{gnu}
3789 products. If you obtained the binary utilities from a support
3790 organization, we recommend you contact that organization first.
3792 You can find contact information for many support companies and
3793 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3797 In any event, we also recommend that you send bug reports for the binary
3798 utilities to @value{BUGURL}.
3801 The fundamental principle of reporting bugs usefully is this:
3802 @strong{report all the facts}. If you are not sure whether to state a
3803 fact or leave it out, state it!
3805 Often people omit facts because they think they know what causes the
3806 problem and assume that some details do not matter. Thus, you might
3807 assume that the name of a file you use in an example does not matter.
3808 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3809 a stray memory reference which happens to fetch from the location where
3810 that pathname is stored in memory; perhaps, if the pathname were
3811 different, the contents of that location would fool the utility into
3812 doing the right thing despite the bug. Play it safe and give a
3813 specific, complete example. That is the easiest thing for you to do,
3814 and the most helpful.
3816 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3817 it is new to us. Therefore, always write your bug reports on the assumption
3818 that the bug has not been reported previously.
3820 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3821 bell?'' This cannot help us fix a bug, so it is basically useless. We
3822 respond by asking for enough details to enable us to investigate.
3823 You might as well expedite matters by sending them to begin with.
3825 To enable us to fix the bug, you should include all these things:
3829 The version of the utility. Each utility announces it if you start it
3830 with the @option{--version} argument.
3832 Without this, we will not know whether there is any point in looking for
3833 the bug in the current version of the binary utilities.
3836 Any patches you may have applied to the source, including any patches
3837 made to the @code{BFD} library.
3840 The type of machine you are using, and the operating system name and
3844 What compiler (and its version) was used to compile the utilities---e.g.
3848 The command arguments you gave the utility to observe the bug. To
3849 guarantee you will not omit something important, list them all. A copy
3850 of the Makefile (or the output from make) is sufficient.
3852 If we were to try to guess the arguments, we would probably guess wrong
3853 and then we might not encounter the bug.
3856 A complete input file, or set of input files, that will reproduce the
3857 bug. If the utility is reading an object file or files, then it is
3858 generally most helpful to send the actual object files.
3860 If the source files were produced exclusively using @sc{gnu} programs
3861 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3862 may be OK to send the source files rather than the object files. In
3863 this case, be sure to say exactly what version of @command{gcc}, or
3864 whatever, was used to produce the object files. Also say how
3865 @command{gcc}, or whatever, was configured.
3868 A description of what behavior you observe that you believe is
3869 incorrect. For example, ``It gets a fatal signal.''
3871 Of course, if the bug is that the utility gets a fatal signal, then we
3872 will certainly notice it. But if the bug is incorrect output, we might
3873 not notice unless it is glaringly wrong. You might as well not give us
3874 a chance to make a mistake.
3876 Even if the problem you experience is a fatal signal, you should still
3877 say so explicitly. Suppose something strange is going on, such as your
3878 copy of the utility is out of sync, or you have encountered a bug in
3879 the C library on your system. (This has happened!) Your copy might
3880 crash and ours would not. If you told us to expect a crash, then when
3881 ours fails to crash, we would know that the bug was not happening for
3882 us. If you had not told us to expect a crash, then we would not be able
3883 to draw any conclusion from our observations.
3886 If you wish to suggest changes to the source, send us context diffs, as
3887 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3888 option. Always send diffs from the old file to the new file. If you
3889 wish to discuss something in the @command{ld} source, refer to it by
3890 context, not by line number.
3892 The line numbers in our development sources will not match those in your
3893 sources. Your line numbers would convey no useful information to us.
3896 Here are some things that are not necessary:
3900 A description of the envelope of the bug.
3902 Often people who encounter a bug spend a lot of time investigating
3903 which changes to the input file will make the bug go away and which
3904 changes will not affect it.
3906 This is often time consuming and not very useful, because the way we
3907 will find the bug is by running a single example under the debugger
3908 with breakpoints, not by pure deduction from a series of examples.
3909 We recommend that you save your time for something else.
3911 Of course, if you can find a simpler example to report @emph{instead}
3912 of the original one, that is a convenience for us. Errors in the
3913 output will be easier to spot, running under the debugger will take
3914 less time, and so on.
3916 However, simplification is not vital; if you do not want to do this,
3917 report the bug anyway and send us the entire test case you used.
3920 A patch for the bug.
3922 A patch for the bug does help us if it is a good one. But do not omit
3923 the necessary information, such as the test case, on the assumption that
3924 a patch is all we need. We might see problems with your patch and decide
3925 to fix the problem another way, or we might not understand it at all.
3927 Sometimes with programs as complicated as the binary utilities it is
3928 very hard to construct an example that will make the program follow a
3929 certain path through the code. If you do not send us the example, we
3930 will not be able to construct one, so we will not be able to verify that
3933 And if we cannot understand what bug you are trying to fix, or why your
3934 patch should be an improvement, we will not install it. A test case will
3935 help us to understand.
3938 A guess about what the bug is or what it depends on.
3940 Such guesses are usually wrong. Even we cannot guess right about such
3941 things without first using the debugger to find the facts.
3946 @node Binutils Index
3947 @unnumbered Binutils Index