1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
8 * Binutils: (binutils). The GNU binary utilities "ar", "objcopy",
9 "objdump", "nm", "nlmconv", "size",
10 "strings", "strip", and "ranlib".
16 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 1997 Free Software Foundation, Inc.
18 Permission is granted to make and distribute verbatim copies of
19 this manual provided the copyright notice and this permission notice
20 are preserved on all copies.
23 Permission is granted to process this file through TeX and print the
24 results, provided the printed document carries a copying permission
25 notice identical to this one except for the removal of this paragraph
26 (this paragraph not being relevant to the printed manual).
30 Permission is granted to copy and distribute modified versions of this
31 manual under the conditions for verbatim copying, provided also that
32 the entire resulting derived work is distributed under the terms of a
33 permission notice identical to this one.
35 Permission is granted to copy and distribute translations of this manual
36 into another language, under the above conditions for modified versions.
41 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
42 @c "objdump", "nm", "size", "strings", "strip", and "ranlib".
44 @c Copyright (C) 1991, 92, 93, 94, 95, 96, 1997 Free Software Foundation, Inc.
46 @c This text may be freely distributed under the terms of the GNU
47 @c General Public License.
50 @setchapternewpage odd
51 @settitle @sc{gnu} Binary Utilities
54 @title The @sc{gnu} Binary Utilities
55 @subtitle Version @value{VERSION}
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 \TeX{}info \texinfoversion\par }
68 @vskip 0pt plus 1filll
69 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 1997 Free Software Foundation, Inc.
71 Permission is granted to make and distribute verbatim copies of
72 this manual provided the copyright notice and this permission notice
73 are preserved on all copies.
75 Permission is granted to copy and distribute modified versions of this
76 manual under the conditions for verbatim copying, provided also that
77 the entire resulting derived work is distributed under the terms of a
78 permission notice identical to this one.
80 Permission is granted to copy and distribute translations of this manual
81 into another language, under the above conditions for modified versions.
88 This brief manual contains preliminary documentation for the @sc{gnu} binary
89 utilities (collectively version @value{VERSION}):
94 Create, modify, and extract from archives
97 List symbols from object files
100 Copy and translate object files
103 Display information from object files
106 Generate index to archive contents
109 List file section sizes and total size
112 List printable strings from files
118 Demangle encoded C++ symbols
121 Convert addresses into file names and line numbers
124 Convert object code into a Netware Loadable Module
129 * ar:: Create, modify, and extract from archives
130 * nm:: List symbols from object files
131 * objcopy:: Copy and translate object files
132 * objdump:: Display information from object files
133 * ranlib:: Generate index to archive contents
134 * size:: List section sizes and total size
135 * strings:: List printable strings from files
136 * strip:: Discard symbols
137 * c++filt:: Filter to demangle encoded C++ symbols
138 * addr2line:: Convert addresses to file and line
139 * nlmconv:: Converts object code into an NLM
140 * Selecting The Target System:: How these utilities determine the target.
141 * Reporting Bugs:: Reporting Bugs
150 @cindex collections of files
152 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
153 ar -M [ <mri-script ]
156 The @sc{gnu} @code{ar} program creates, modifies, and extracts from
157 archives. An @dfn{archive} is a single file holding a collection of
158 other files in a structure that makes it possible to retrieve
159 the original individual files (called @dfn{members} of the archive).
161 The original files' contents, mode (permissions), timestamp, owner, and
162 group are preserved in the archive, and can be restored on
166 @sc{gnu} @code{ar} can maintain archives whose members have names of any
167 length; however, depending on how @code{ar} is configured on your
168 system, a limit on member-name length may be imposed for compatibility
169 with archive formats maintained with other tools. If it exists, the
170 limit is often 15 characters (typical of formats related to a.out) or 16
171 characters (typical of formats related to coff).
174 @code{ar} is considered a binary utility because archives of this sort
175 are most often used as @dfn{libraries} holding commonly needed
179 @code{ar} creates an index to the symbols defined in relocatable
180 object modules in the archive when you specify the modifier @samp{s}.
181 Once created, this index is updated in the archive whenever @code{ar}
182 makes a change to its contents (save for the @samp{q} update operation).
183 An archive with such an index speeds up linking to the library, and
184 allows routines in the library to call each other without regard to
185 their placement in the archive.
187 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
188 table. If an archive lacks the table, another form of @code{ar} called
189 @code{ranlib} can be used to add just the table.
191 @cindex compatibility, @code{ar}
192 @cindex @code{ar} compatibility
193 @sc{gnu} @code{ar} is designed to be compatible with two different
194 facilities. You can control its activity using command-line options,
195 like the different varieties of @code{ar} on Unix systems; or, if you
196 specify the single command-line option @samp{-M}, you can control it
197 with a script supplied via standard input, like the MRI ``librarian''
201 * ar cmdline:: Controlling @code{ar} on the command line
202 * ar scripts:: Controlling @code{ar} with a script
207 @section Controlling @code{ar} on the command line
210 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
213 @cindex Unix compatibility, @code{ar}
214 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
215 arguments to execute: one keyletter specifying the @emph{operation}
216 (optionally accompanied by other keyletters specifying
217 @emph{modifiers}), and the archive name to act on.
219 Most operations can also accept further @var{member} arguments,
220 specifying particular files to operate on.
222 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
223 flags @var{mod} in any order, within the first command-line argument.
225 If you wish, you may begin the first command-line argument with a
228 @cindex operations on archive
229 The @var{p} keyletter specifies what operation to execute; it may be
230 any of the following, but you must specify only one of them:
234 @cindex deleting from archive
235 @emph{Delete} modules from the archive. Specify the names of modules to
236 be deleted as @var{member}@dots{}; the archive is untouched if you
237 specify no files to delete.
239 If you specify the @samp{v} modifier, @code{ar} lists each module
243 @cindex moving in archive
244 Use this operation to @emph{move} members in an archive.
246 The ordering of members in an archive can make a difference in how
247 programs are linked using the library, if a symbol is defined in more
250 If no modifiers are used with @code{m}, any members you name in the
251 @var{member} arguments are moved to the @emph{end} of the archive;
252 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
253 specified place instead.
256 @cindex printing from archive
257 @emph{Print} the specified members of the archive, to the standard
258 output file. If the @samp{v} modifier is specified, show the member
259 name before copying its contents to standard output.
261 If you specify no @var{member} arguments, all the files in the archive are
265 @cindex quick append to archive
266 @emph{Quick append}; add the files @var{member}@dots{} to the end of
267 @var{archive}, without checking for replacement.
269 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
270 operation; new members are always placed at the end of the archive.
272 The modifier @samp{v} makes @code{ar} list each file as it is appended.
274 Since the point of this operation is speed, the archive's symbol table
275 index is not updated, even if it already existed; you can use @samp{ar s} or
276 @code{ranlib} explicitly to update the symbol table index.
279 @cindex replacement in archive
280 Insert the files @var{member}@dots{} into @var{archive} (with
281 @emph{replacement}). This operation differs from @samp{q} in that any
282 previously existing members are deleted if their names match those being
285 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
286 displays an error message, and leaves undisturbed any existing members
287 of the archive matching that name.
289 By default, new members are added at the end of the file; but you may
290 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
291 placement relative to some existing member.
293 The modifier @samp{v} used with this operation elicits a line of
294 output for each file inserted, along with one of the letters @samp{a} or
295 @samp{r} to indicate whether the file was appended (no old member
296 deleted) or replaced.
299 @cindex contents of archive
300 Display a @emph{table} listing the contents of @var{archive}, or those
301 of the files listed in @var{member}@dots{} that are present in the
302 archive. Normally only the member name is shown; if you also want to
303 see the modes (permissions), timestamp, owner, group, and size, you can
304 request that by also specifying the @samp{v} modifier.
306 If you do not specify a @var{member}, all files in the archive
309 @cindex repeated names in archive
310 @cindex name duplication in archive
311 If there is more than one file with the same name (say, @samp{fie}) in
312 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
313 first instance; to see them all, you must ask for a complete
314 listing---in our example, @samp{ar t b.a}.
315 @c WRS only; per Gumby, this is implementation-dependent, and in a more
316 @c recent case in fact works the other way.
319 @cindex extract from archive
320 @emph{Extract} members (named @var{member}) from the archive. You can
321 use the @samp{v} modifier with this operation, to request that
322 @code{ar} list each name as it extracts it.
324 If you do not specify a @var{member}, all files in the archive
329 A number of modifiers (@var{mod}) may immediately follow the @var{p}
330 keyletter, to specify variations on an operation's behavior:
334 @cindex relative placement in archive
335 Add new files @emph{after} an existing member of the
336 archive. If you use the modifier @samp{a}, the name of an existing archive
337 member must be present as the @var{relpos} argument, before the
338 @var{archive} specification.
341 Add new files @emph{before} an existing member of the
342 archive. If you use the modifier @samp{b}, the name of an existing archive
343 member must be present as the @var{relpos} argument, before the
344 @var{archive} specification. (same as @samp{i}).
347 @cindex creating archives
348 @emph{Create} the archive. The specified @var{archive} is always
349 created if it did not exist, when you request an update. But a warning is
350 issued unless you specify in advance that you expect to create it, by
354 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
355 names of any length. This will cause it to create archives which are
356 not compatible with the native @code{ar} program on some systems. If
357 this is a concern, the @samp{f} modifier may be used to truncate file
358 names when putting them in the archive.
361 Insert new files @emph{before} an existing member of the
362 archive. If you use the modifier @samp{i}, the name of an existing archive
363 member must be present as the @var{relpos} argument, before the
364 @var{archive} specification. (same as @samp{b}).
367 This modifier is accepted but not used.
368 @c whaffor ar l modifier??? presumably compat; with
369 @c what???---doc@@cygnus.com, 25jan91
372 @cindex dates in archive
373 Preserve the @emph{original} dates of members when extracting them. If
374 you do not specify this modifier, files extracted from the archive
375 are stamped with the time of extraction.
378 @cindex writing archive index
379 Write an object-file index into the archive, or update an existing one,
380 even if no other change is made to the archive. You may use this modifier
381 flag either with any operation, or alone. Running @samp{ar s} on an
382 archive is equivalent to running @samp{ranlib} on it.
385 @cindex updating an archive
386 Normally, @samp{ar r}@dots{} inserts all files
387 listed into the archive. If you would like to insert @emph{only} those
388 of the files you list that are newer than existing members of the same
389 names, use this modifier. The @samp{u} modifier is allowed only for the
390 operation @samp{r} (replace). In particular, the combination @samp{qu} is
391 not allowed, since checking the timestamps would lose any speed
392 advantage from the operation @samp{q}.
395 This modifier requests the @emph{verbose} version of an operation. Many
396 operations display additional information, such as filenames processed,
397 when the modifier @samp{v} is appended.
400 This modifier shows the version number of @code{ar}.
404 @section Controlling @code{ar} with a script
407 ar -M [ <@var{script} ]
410 @cindex MRI compatibility, @code{ar}
411 @cindex scripts, @code{ar}
412 If you use the single command-line option @samp{-M} with @code{ar}, you
413 can control its operation with a rudimentary command language. This
414 form of @code{ar} operates interactively if standard input is coming
415 directly from a terminal. During interactive use, @code{ar} prompts for
416 input (the prompt is @samp{AR >}), and continues executing even after
417 errors. If you redirect standard input to a script file, no prompts are
418 issued, and @code{ar} abandons execution (with a nonzero exit code)
421 The @code{ar} command language is @emph{not} designed to be equivalent
422 to the command-line options; in fact, it provides somewhat less control
423 over archives. The only purpose of the command language is to ease the
424 transition to @sc{gnu} @code{ar} for developers who already have scripts
425 written for the MRI ``librarian'' program.
427 The syntax for the @code{ar} command language is straightforward:
430 commands are recognized in upper or lower case; for example, @code{LIST}
431 is the same as @code{list}. In the following descriptions, commands are
432 shown in upper case for clarity.
435 a single command may appear on each line; it is the first word on the
439 empty lines are allowed, and have no effect.
442 comments are allowed; text after either of the characters @samp{*}
443 or @samp{;} is ignored.
446 Whenever you use a list of names as part of the argument to an @code{ar}
447 command, you can separate the individual names with either commas or
448 blanks. Commas are shown in the explanations below, for clarity.
451 @samp{+} is used as a line continuation character; if @samp{+} appears
452 at the end of a line, the text on the following line is considered part
453 of the current command.
456 Here are the commands you can use in @code{ar} scripts, or when using
457 @code{ar} interactively. Three of them have special significance:
459 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
460 a temporary file required for most of the other commands.
462 @code{SAVE} commits the changes so far specified by the script. Prior
463 to @code{SAVE}, commands affect only the temporary copy of the current
467 @item ADDLIB @var{archive}
468 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
469 Add all the contents of @var{archive} (or, if specified, each named
470 @var{module} from @var{archive}) to the current archive.
472 Requires prior use of @code{OPEN} or @code{CREATE}.
474 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
475 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
476 @c else like "ar q..."
477 Add each named @var{member} as a module in the current archive.
479 Requires prior use of @code{OPEN} or @code{CREATE}.
482 Discard the contents of the current archive, cancelling the effect of
483 any operations since the last @code{SAVE}. May be executed (with no
484 effect) even if no current archive is specified.
486 @item CREATE @var{archive}
487 Creates an archive, and makes it the current archive (required for many
488 other commands). The new archive is created with a temporary name; it
489 is not actually saved as @var{archive} until you use @code{SAVE}.
490 You can overwrite existing archives; similarly, the contents of any
491 existing file named @var{archive} will not be destroyed until @code{SAVE}.
493 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
494 Delete each listed @var{module} from the current archive; equivalent to
495 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
497 Requires prior use of @code{OPEN} or @code{CREATE}.
499 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
500 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
501 List each named @var{module} present in @var{archive}. The separate
502 command @code{VERBOSE} specifies the form of the output: when verbose
503 output is off, output is like that of @samp{ar -t @var{archive}
504 @var{module}@dots{}}. When verbose output is on, the listing is like
505 @samp{ar -tv @var{archive} @var{module}@dots{}}.
507 Output normally goes to the standard output stream; however, if you
508 specify @var{outputfile} as a final argument, @code{ar} directs the
512 Exit from @code{ar}, with a @code{0} exit code to indicate successful
513 completion. This command does not save the output file; if you have
514 changed the current archive since the last @code{SAVE} command, those
517 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
518 Extract each named @var{module} from the current archive, writing them
519 into the current directory as separate files. Equivalent to @samp{ar -x
520 @var{archive} @var{module}@dots{}}.
522 Requires prior use of @code{OPEN} or @code{CREATE}.
525 @c FIXME Tokens but no commands???
532 Display full contents of the current archive, in ``verbose'' style
533 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
534 tv @var{archive}}). (This single command is a @sc{gnu} @code{ld}
535 enhancement, rather than present for MRI compatibility.)
537 Requires prior use of @code{OPEN} or @code{CREATE}.
539 @item OPEN @var{archive}
540 Opens an existing archive for use as the current archive (required for
541 many other commands). Any changes as the result of subsequent commands
542 will not actually affect @var{archive} until you next use @code{SAVE}.
544 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
545 In the current archive, replace each existing @var{module} (named in
546 the @code{REPLACE} arguments) from files in the current working directory.
547 To execute this command without errors, both the file, and the module in
548 the current archive, must exist.
550 Requires prior use of @code{OPEN} or @code{CREATE}.
553 Toggle an internal flag governing the output from @code{DIRECTORY}.
554 When the flag is on, @code{DIRECTORY} output matches output from
555 @samp{ar -tv }@dots{}.
558 Commit your changes to the current archive, and actually save it as a
559 file with the name specified in the last @code{CREATE} or @code{OPEN}
562 Requires prior use of @code{OPEN} or @code{CREATE}.
571 The @sc{gnu} linker @code{ld} is now described in a separate manual.
572 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
581 nm [ -a | --debug-syms ] [ -g | --extern-only ]
582 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
583 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
584 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
585 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
586 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
587 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
588 [ --defined-only ] [-l | --line-numbers ]
589 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
592 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
593 If no object files are listed as arguments, @code{nm} assumes
596 For each symbol, @code{nm} shows:
600 The symbol value, in the radix selected by options (see below), or
601 hexadecimal by default.
604 The symbol type. At least the following types are used; others are, as
605 well, depending on the object file format. If lowercase, the symbol is
606 local; if uppercase, the symbol is global (external).
608 @c Some more detail on exactly what these symbol types are used for
612 The symbol's value is absolute, and will not be changed by further
616 The symbol is in the uninitialized data section (known as BSS).
619 The symbol is common. Common symbols are uninitialized data. When
620 linking, multiple common symbols may appear with the same name. If the
621 symbol is defined anywhere, the common symbols are treated as undefined
622 references. For more details on common symbols, see the discussion of
623 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
626 The symbol is in the initialized data section.
629 The symbol is in an initialized data section for small objects. Some
630 object file formats permit more efficient access to small data objects,
631 such as a global int variable as opposed to a large global array.
634 The symbol is an indirect reference to another symbol. This is a GNU
635 extension to the a.out object file format which is rarely used.
638 The symbol is a debugging symbol.
641 The symbol is in a read only data section.
644 The symbol is in an uninitialized data section for small objects.
647 The symbol is in the text (code) section.
650 The symbol is undefined.
653 The symbol is weak. When a weak defined symbol is linked with a normal
654 defined symbol, the normal defined symbol is used with no error. When a
655 weak undefined symbol is linked and the symbol is not defined, the value
656 of the weak symbol becomes zero with no error.
659 The symbol is a stabs symbol in an a.out object file. In this case, the
660 next values printed are the stabs other field, the stabs desc field, and
661 the stab type. Stabs symbols are used to hold debugging information;
662 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
663 ``stabs'' debug format}.
666 The symbol type is unknown, or object file format specific.
673 The long and short forms of options, shown here as alternatives, are
679 @itemx --print-file-name
680 @cindex input file name
682 @cindex source file name
683 Precede each symbol by the name of the input file (or archive element)
684 in which it was found, rather than identifying the input file once only,
685 before all of its symbols.
689 @cindex debugging symbols
690 Display all symbols, even debugger-only symbols; normally these are not
694 @cindex @code{nm} format
695 @cindex @code{nm} compatibility
696 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
700 @cindex demangling in nm
701 Decode (@dfn{demangle}) low-level symbol names into user-level names.
702 Besides removing any initial underscore prepended by the system, this
703 makes C++ function names readable. @xref{c++filt}, for more information
707 Do not demangle low-level symbol names. This is the default.
711 @cindex dynamic symbols
712 Display the dynamic symbols rather than the normal symbols. This is
713 only meaningful for dynamic objects, such as certain types of shared
716 @item -f @var{format}
717 @itemx --format=@var{format}
718 @cindex @code{nm} format
719 @cindex @code{nm} compatibility
720 Use the output format @var{format}, which can be @code{bsd},
721 @code{sysv}, or @code{posix}. The default is @code{bsd}.
722 Only the first character of @var{format} is significant; it can be
723 either upper or lower case.
727 @cindex external symbols
728 Display only external symbols.
731 @itemx --line-numbers
732 @cindex symbol line numbers
733 For each symbol, use debugging information to try to find a filename and
734 line number. For a defined symbol, look for the line number of the
735 address of the symbol. For an undefined symbol, look for the line
736 number of a relocation entry which refers to the symbol. If line number
737 information can be found, print it after the other symbol information.
741 @itemx --numeric-sort
742 Sort symbols numerically by their addresses, rather than alphabetically
747 @cindex sorting symbols
748 Do not bother to sort the symbols in any order; print them in the order
753 Use the POSIX.2 standard output format instead of the default format.
754 Equivalent to @samp{-f posix}.
758 @cindex symbol index, listing
759 When listing symbols from archive members, include the index: a mapping
760 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
761 contain definitions for which names.
764 @itemx --reverse-sort
765 Reverse the order of the sort (whether numeric or alphabetic); let the
769 Sort symbols by size. The size is computed as the difference between
770 the value of the symbol and the value of the symbol with the next higher
771 value. The size of the symbol is printed, rather than the value.
774 @itemx --radix=@var{radix}
775 Use @var{radix} as the radix for printing the symbol values. It must be
776 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
778 @item --target=@var{bfdname}
779 @cindex object code format
780 Specify an object code format other than your system's default format.
781 @xref{Target Selection}, for more information.
784 @itemx --undefined-only
785 @cindex external symbols
786 @cindex undefined symbols
787 Display only undefined symbols (those external to each object file).
790 @cindex external symbols
791 @cindex undefined symbols
792 Display only defined symbols for each object file.
796 Show the version number of @code{nm} and exit.
799 Show a summary of the options to @code{nm} and exit.
806 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
807 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
808 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
809 [ -S | --strip-all ] [ -g | --strip-debug ]
810 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
811 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
812 [ -x | --discard-all ] [ -X | --discard-locals ]
813 [ -b @var{byte} | --byte=@var{byte} ]
814 [ -i @var{interleave} | --interleave=@var{interleave} ]
815 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
816 [ -p | --preserve-dates ] [ --debugging ]
817 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
818 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
819 [ --adjust-vma=@var{incr} ]
820 [ --adjust-section-vma=@var{section}@{=,+,-@}@var{val} ]
821 [ --adjust-warnings ] [ --no-adjust-warnings ]
822 [ --set-section-flags=@var{section}=@var{flags} ]
823 [ --add-section=@var{sectionname}=@var{filename} ]
824 [ --change-leading-char ] [ --remove-leading-char ]
826 [ -v | --verbose ] [ -V | --version ] [ --help ]
827 @var{infile} [@var{outfile}]
830 The @sc{gnu} @code{objcopy} utility copies the contents of an object
831 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
832 read and write the object files. It can write the destination object
833 file in a format different from that of the source object file. The
834 exact behavior of @code{objcopy} is controlled by command-line options.
836 @code{objcopy} creates temporary files to do its translations and
837 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
838 translation work; it has access to all the formats described in @sc{bfd}
839 and thus is able to recognize most formats without being told
840 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
842 @code{objcopy} can be used to generate S-records by using an output
843 target of @samp{srec} (e.g., use @samp{-O srec}).
845 @code{objcopy} can be used to generate a raw binary file by using an
846 output target of @samp{binary} (e.g., use @samp{-O binary}). When
847 @code{objcopy} generates a raw binary file, it will essentially produce
848 a memory dump of the contents of the input object file. All symbols and
849 relocation information will be discarded. The memory dump will start at
850 the load address of the lowest section copied into the output file.
852 When generating an S-record or a raw binary file, it may be helpful to
853 use @samp{-S} to remove sections containing debugging information. In
854 some cases @samp{-R} will be useful to remove sections which contain
855 information which is not needed by the binary file.
860 The source and output files, respectively.
861 If you do not specify @var{outfile}, @code{objcopy} creates a
862 temporary file and destructively renames the result with
863 the name of @var{infile}.
865 @item -I @var{bfdname}
866 @itemx --input-target=@var{bfdname}
867 Consider the source file's object format to be @var{bfdname}, rather than
868 attempting to deduce it. @xref{Target Selection}, for more information.
870 @item -O @var{bfdname}
871 @itemx --output-target=@var{bfdname}
872 Write the output file using the object format @var{bfdname}.
873 @xref{Target Selection}, for more information.
875 @item -F @var{bfdname}
876 @itemx --target=@var{bfdname}
877 Use @var{bfdname} as the object format for both the input and the output
878 file; i.e., simply transfer data from source to destination with no
879 translation. @xref{Target Selection}, for more information.
881 @item -R @var{sectionname}
882 @itemx --remove-section=@var{sectionname}
883 Remove any section named @var{sectionname} from the output file. This
884 option may be given more than once. Note that using this option
885 inappropriately may make the output file unusable.
889 Do not copy relocation and symbol information from the source file.
893 Do not copy debugging symbols from the source file.
895 @item --strip-unneeded
896 Strip all symbols that are not needed for relocation processing.
898 @item -K @var{symbolname}
899 @itemx --keep-symbol=@var{symbolname}
900 Copy only symbol @var{symbolname} from the source file. This option may
901 be given more than once.
903 @item -N @var{symbolname}
904 @itemx --strip-symbol=@var{symbolname}
905 Do not copy symbol @var{symbolname} from the source file. This option
906 may be given more than once, and may be combined with strip options
907 other than @code{-K}.
911 Do not copy non-global symbols from the source file.
912 @c FIXME any reason to prefer "non-global" to "local" here?
915 @itemx --discard-locals
916 Do not copy compiler-generated local symbols.
917 (These usually start with @samp{L} or @samp{.}.)
920 @itemx --byte=@var{byte}
921 Keep only every @var{byte}th byte of the input file (header data is not
922 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
923 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
924 option, or the default of 4. This option is useful for creating files
925 to program @sc{rom}. It is typically used with an @code{srec} output
928 @item -i @var{interleave}
929 @itemx --interleave=@var{interleave}
930 Only copy one out of every @var{interleave} bytes. Select which byte to
931 copy with the @var{-b} or @samp{--byte} option. The default is 4.
932 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
936 @itemx --preserve-dates
937 Set the access and modification dates of the output file to be the same
938 as those of the input file.
941 Convert debugging information, if possible. This is not the default
942 because only certain debugging formats are supported, and the
943 conversion process can be time consuming.
945 @item --gap-fill @var{val}
946 Fill gaps between sections with @var{val}. This is done by increasing
947 the size of the section with the lower address, and filling in the extra
948 space created with @var{val}.
950 @item --pad-to @var{address}
951 Pad the output file up to the virtual address @var{address}. This is
952 done by increasing the size of the last section. The extra space is
953 filled in with the value specified by @samp{--gap-fill} (default zero).
955 @item --set-start @var{val}
956 Set the address of the new file to @var{val}. Not all object file
957 formats support setting the start address.
959 @item --adjust-start @var{incr}
960 Adjust the start address by adding @var{incr}. Not all object file
961 formats support setting the start address.
963 @item --adjust-vma @var{incr}
964 Adjust the address of all sections, as well as the start address, by
965 adding @var{incr}. Some object file formats do not permit section
966 addresses to be changed arbitrarily. Note that this does not relocate
967 the sections; if the program expects sections to be loaded at a certain
968 address, and this option is used to change the sections such that they
969 are loaded at a different address, the program may fail.
971 @item --adjust-section-vma @var{section}@{=,+,-@}@var{val}
972 Set or adjust the address of the named @var{section}. If @samp{=} is
973 used, the section address is set to @var{val}. Otherwise, @var{val} is
974 added to or subtracted from the section address. See the comments under
975 @samp{--adjust-vma}, above. If @var{section} does not exist in the
976 input file, a warning will be issued, unless @samp{--no-adjust-warnings}
979 @item --adjust-warnings
980 If @samp{--adjust-section-vma} is used, and the named section does not
981 exist, issue a warning. This is the default.
983 @item --no-adjust-warnings
984 Do not issue a warning if @samp{--adjust-section-vma} is used, even if
985 the named section does not exist.
987 @item --set-section-flags @var{section}=@var{flags}
988 Set the flags for the named section. The @var{flags} argument is a
989 comma separated string of flag names. The recognized names are
990 @samp{alloc}, @samp{load}, @samp{readonly}, @samp{code}, @samp{data},
991 and @samp{rom}. Not all flags are meaningful for all object file
994 @item --add-section @var{sectionname}=@var{filename}
995 Add a new section named @var{sectionname} while copying the file. The
996 contents of the new section are taken from the file @var{filename}. The
997 size of the section will be the size of the file. This option only
998 works on file formats which can support sections with arbitrary names.
1000 @item --change-leading-char
1001 Some object file formats use special characters at the start of
1002 symbols. The most common such character is underscore, which compilers
1003 often add before every symbol. This option tells @code{objcopy} to
1004 change the leading character of every symbol when it converts between
1005 object file formats. If the object file formats use the same leading
1006 character, this option has no effect. Otherwise, it will add a
1007 character, or remove a character, or change a character, as
1010 @item --remove-leading-char
1011 If the first character of a global symbol is a special symbol leading
1012 character used by the object file format, remove the character. The
1013 most common symbol leading character is underscore. This option will
1014 remove a leading underscore from all global symbols. This can be useful
1015 if you want to link together objects of different file formats with
1016 different conventions for symbol names. This is different from
1017 @code{--change-leading-char} because it always changes the symbol name
1018 when appropriate, regardless of the object file format of the output
1022 Change all global symbols in the file to be weak. This can be useful
1023 when building an object which will be linked against other objects using
1024 the @code{-R} option to the linker. This option is only effective when
1025 using an object file format which supports weak symbols.
1029 Show the version number of @code{objcopy}.
1033 Verbose output: list all object files modified. In the case of
1034 archives, @samp{objcopy -V} lists all members of the archive.
1037 Show a summary of the options to @code{objcopy}.
1043 @cindex object file information
1047 objdump [ -a | --archive-headers ]
1048 [ -b @var{bfdname} | --target=@var{bfdname} ] [ --debugging ]
1049 [ -C | --demangle ] [ -d | --disassemble ]
1050 [ -D | --disassemble-all ] [ --disassemble-zeroes ]
1051 [ -EB | -EL | --endian=@{big | little @} ]
1052 [ -f | --file-headers ]
1053 [ -h | --section-headers | --headers ] [ -i | --info ]
1054 [ -j @var{section} | --section=@var{section} ]
1055 [ -l | --line-numbers ] [ -S | --source ]
1056 [ -m @var{machine} | --architecture=@var{machine} ]
1057 [ -r | --reloc ] [ -R | --dynamic-reloc ]
1058 [ -s | --full-contents ] [ --stabs ]
1059 [ -t | --syms ] [ -T | --dynamic-syms ] [ -x | --all-headers ]
1060 [ -w | --wide ] [ --start-address=@var{address} ]
1061 [ --stop-address=@var{address} ]
1062 [ --prefix-addresses] [ --[no-]show-raw-insn ]
1063 [ --adjust-vma=@var{offset} ]
1064 [ --version ] [ --help ]
1065 @var{objfile}@dots{}
1068 @code{objdump} displays information about one or more object files.
1069 The options control what particular information to display. This
1070 information is mostly useful to programmers who are working on the
1071 compilation tools, as opposed to programmers who just want their
1072 program to compile and work.
1074 @var{objfile}@dots{} are the object files to be examined. When you
1075 specify archives, @code{objdump} shows information on each of the member
1078 The long and short forms of options, shown here as alternatives, are
1079 equivalent. At least one option besides @samp{-l} must be given.
1083 @itemx --archive-header
1084 @cindex archive headers
1085 If any of the @var{objfile} files are archives, display the archive
1086 header information (in a format similar to @samp{ls -l}). Besides the
1087 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1088 the object file format of each archive member.
1090 @item --adjust-vma=@var{offset}
1091 @cindex section addresses in objdump
1092 @cindex VMA in objdump
1093 When dumping information, first add @var{offset} to all the section
1094 addresses. This is useful if the section addresses do not correspond to
1095 the symbol table, which can happen when putting sections at particular
1096 addresses when using a format which can not represent section addresses,
1099 @item -b @var{bfdname}
1100 @itemx --target=@var{bfdname}
1101 @cindex object code format
1102 Specify that the object-code format for the object files is
1103 @var{bfdname}. This option may not be necessary; @var{objdump} can
1104 automatically recognize many formats.
1108 objdump -b oasys -m vax -h fu.o
1111 displays summary information from the section headers (@samp{-h}) of
1112 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1113 file in the format produced by Oasys compilers. You can list the
1114 formats available with the @samp{-i} option.
1115 @xref{Target Selection}, for more information.
1119 @cindex demangling in objdump
1120 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1121 Besides removing any initial underscore prepended by the system, this
1122 makes C++ function names readable. @xref{c++filt}, for more information
1126 Display debugging information. This attempts to parse debugging
1127 information stored in the file and print it out using a C like syntax.
1128 Only certain types of debugging information have been implemented.
1131 @itemx --disassemble
1132 @cindex disassembling object code
1133 @cindex machine instructions
1134 Display the assembler mnemonics for the machine instructions from
1135 @var{objfile}. This option only disassembles those sections which are
1136 expected to contain instructions.
1139 @itemx --disassemble-all
1140 Like @samp{-d}, but disassemble the contents of all sections, not just
1141 those expected to contain instructions.
1143 @item --prefix-addresses
1144 When disassembling, print the complete address on each line. This is
1145 the older disassembly format.
1147 @item --disassemble-zeroes
1148 Normally the disassembly output will skip blocks of zeroes. This
1149 option directs the disassembler to disassemble those blocks, just like
1154 @itemx --endian=@{big|little@}
1156 @cindex disassembly endianness
1157 Specify the endianness of the object files. This only affects
1158 disassembly. This can be useful when disassembling a file format which
1159 does not describe endianness information, such as S-records.
1162 @itemx --file-header
1163 @cindex object file header
1164 Display summary information from the overall header of
1165 each of the @var{objfile} files.
1168 @itemx --section-header
1170 @cindex section headers
1171 Display summary information from the section headers of the
1174 File segments may be relocated to nonstandard addresses, for example by
1175 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1176 @code{ld}. However, some object file formats, such as a.out, do not
1177 store the starting address of the file segments. In those situations,
1178 although @code{ld} relocates the sections correctly, using @samp{objdump
1179 -h} to list the file section headers cannot show the correct addresses.
1180 Instead, it shows the usual addresses, which are implicit for the
1184 Print a summary of the options to @code{objdump} and exit.
1188 @cindex architectures available
1189 @cindex object formats available
1190 Display a list showing all architectures and object formats available
1191 for specification with @samp{-b} or @samp{-m}.
1194 @itemx --section=@var{name}
1195 @cindex section information
1196 Display information only for section @var{name}.
1199 @itemx --line-numbers
1200 @cindex source filenames for object files
1201 Label the display (using debugging information) with the filename and
1202 source line numbers corresponding to the object code or relocs shown.
1203 Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1205 @item -m @var{machine}
1206 @itemx --architecture=@var{machine}
1207 @cindex architecture
1208 @cindex disassembly architecture
1209 Specify the architecture to use when disassembling object files. This
1210 can be useful when disasembling object files which do not describe
1211 architecture information, such as S-records. You can list the available
1212 architectures with the @samp{-i} option.
1216 @cindex relocation entries, in object file
1217 Print the relocation entries of the file. If used with @samp{-d} or
1218 @samp{-D}, the relocations are printed interspersed with the
1222 @itemx --dynamic-reloc
1223 @cindex dynamic relocation entries, in object file
1224 Print the dynamic relocation entries of the file. This is only
1225 meaningful for dynamic objects, such as certain types of shared
1229 @itemx --full-contents
1230 @cindex sections, full contents
1231 @cindex object file sections
1232 Display the full contents of any sections requested.
1236 @cindex source disassembly
1237 @cindex disassembly, with source
1238 Display source code intermixed with disassembly, if possible. Implies
1241 @item --show-raw-insn
1242 When disassembling instructions, print the instruction in hex as well as
1243 in symbolic form. This is the default except when
1244 @code{--prefix-addresses} is used.
1246 @item --no-show-raw-insn
1247 When disassembling instructions, do not print the instruction bytes.
1248 This is the default when @code{--prefix-addresses} is used.
1253 @cindex debug symbols
1254 @cindex ELF object file format
1255 Display the full contents of any sections requested. Display the
1256 contents of the .stab and .stab.index and .stab.excl sections from an
1257 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1258 @code{.stab} debugging symbol-table entries are carried in an ELF
1259 section. In most other file formats, debugging symbol-table entries are
1260 interleaved with linkage symbols, and are visible in the @samp{--syms}
1261 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1262 Overview,stabs.info, The ``stabs'' debug format}.
1264 @item --start-address=@var{address}
1265 @cindex start-address
1266 Start displaying data at the specified address. This affects the output
1267 of the @code{-d}, @code{-r} and @code{-s} options.
1269 @item --stop-address=@var{address}
1270 @cindex stop-address
1271 Stop displaying data at the specified address. This affects the output
1272 of the @code{-d}, @code{-r} and @code{-s} options.
1276 @cindex symbol table entries, printing
1277 Print the symbol table entries of the file.
1278 This is similar to the information provided by the @samp{nm} program.
1281 @itemx --dynamic-syms
1282 @cindex dynamic symbol table entries, printing
1283 Print the dynamic symbol table entries of the file. This is only
1284 meaningful for dynamic objects, such as certain types of shared
1285 libraries. This is similar to the information provided by the @samp{nm}
1286 program when given the @samp{-D} (@samp{--dynamic}) option.
1289 Print the version number of @code{objdump} and exit.
1293 @cindex all header information, object file
1294 @cindex header information, all
1295 Display all available header information, including the symbol table and
1296 relocation entries. Using @samp{-x} is equivalent to specifying all of
1297 @samp{-a -f -h -r -t}.
1301 @cindex wide output, printing
1302 Format some lines for output devices that have more than 80 columns.
1309 @cindex archive contents
1310 @cindex symbol index
1313 ranlib [-vV] @var{archive}
1316 @code{ranlib} generates an index to the contents of an archive and
1317 stores it in the archive. The index lists each symbol defined by a
1318 member of an archive that is a relocatable object file.
1320 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1322 An archive with such an index speeds up linking to the library and
1323 allows routines in the library to call each other without regard to
1324 their placement in the archive.
1326 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1327 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1333 Show the version number of @code{ranlib}.
1340 @cindex section sizes
1343 size [ -A | -B | --format=@var{compatibility} ]
1344 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1345 [ --target=@var{bfdname} ] [ -V | --version ]
1346 @var{objfile}@dots{}
1349 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1350 size---for each of the object or archive files @var{objfile} in its
1351 argument list. By default, one line of output is generated for each
1352 object file or each module in an archive.
1354 @var{objfile}@dots{} are the object files to be examined.
1356 The command line options have the following meanings:
1361 @itemx --format=@var{compatibility}
1362 @cindex @code{size} display format
1363 Using one of these options, you can choose whether the output from @sc{gnu}
1364 @code{size} resembles output from System V @code{size} (using @samp{-A},
1365 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1366 @samp{--format=berkeley}). The default is the one-line format similar to
1368 @c Bonus for doc-source readers: you can also say --format=strange (or
1369 @c anything else that starts with 's') for sysv, and --format=boring (or
1370 @c anything else that starts with 'b') for Berkeley.
1372 Here is an example of the Berkeley (default) format of output from
1375 size --format=Berkeley ranlib size
1376 text data bss dec hex filename
1377 294880 81920 11592 388392 5ed28 ranlib
1378 294880 81920 11888 388688 5ee50 size
1382 This is the same data, but displayed closer to System V conventions:
1385 size --format=SysV ranlib size
1403 Show a summary of acceptable arguments and options.
1408 @itemx --radix=@var{number}
1409 @cindex @code{size} number format
1410 @cindex radix for section sizes
1411 Using one of these options, you can control whether the size of each
1412 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1413 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1414 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1415 values (8, 10, 16) are supported. The total size is always given in two
1416 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1417 octal and hexadecimal if you're using @samp{-o}.
1419 @item --target=@var{bfdname}
1420 @cindex object code format
1421 Specify that the object-code format for @var{objfile} is
1422 @var{bfdname}. This option may not be necessary; @code{size} can
1423 automatically recognize many formats.
1424 @xref{Target Selection}, for more information.
1428 Display the version number of @code{size}.
1434 @cindex listings strings
1435 @cindex printing strings
1436 @cindex strings, printing
1439 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1440 [--all] [--print-file-name] [--bytes=@var{min-len}]
1441 [--radix=@var{radix}] [--target=@var{bfdname}]
1442 [--help] [--version] @var{file}@dots{}
1445 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1446 character sequences that are at least 4 characters long (or the number
1447 given with the options below) and are followed by an unprintable
1448 character. By default, it only prints the strings from the initialized
1449 and loaded sections of object files; for other types of files, it prints
1450 the strings from the whole file.
1452 @code{strings} is mainly useful for determining the contents of non-text
1459 Do not scan only the initialized and loaded sections of object files;
1460 scan the whole files.
1463 @itemx --print-file-name
1464 Print the name of the file before each string.
1467 Print a summary of the program usage on the standard output and exit.
1469 @itemx -@var{min-len}
1470 @item -n @var{min-len}
1471 @itemx --bytes=@var{min-len}
1472 Print sequences of characters that are at least @var{min-len} characters
1473 long, instead of the default 4.
1476 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1477 act like @samp{-t d} instead. Since we can not be compatible with both
1478 ways, we simply chose one.
1480 @item -t @var{radix}
1481 @itemx --radix=@var{radix}
1482 Print the offset within the file before each string. The single
1483 character argument specifies the radix of the offset---@samp{o} for
1484 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1486 @item --target=@var{bfdname}
1487 @cindex object code format
1488 Specify an object code format other than your system's default format.
1489 @xref{Target Selection}, for more information.
1493 Print the program version number on the standard output and exit.
1500 @cindex removing symbols
1501 @cindex discarding symbols
1502 @cindex symbols, discarding
1505 strip [ -F @var{bfdname} | --target=@var{bfdname} | --target=@var{bfdname} ]
1506 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1507 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1508 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1509 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1510 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1511 [ -x | --discard-all ] [ -X | --discard-locals ]
1512 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1513 [ -o @var{file} ] [ -p | --preserve-dates ]
1514 [ -v | --verbose ] [ -V | --version ] [ --help ]
1515 @var{objfile}@dots{}
1518 @sc{gnu} @code{strip} discards all symbols from object files
1519 @var{objfile}. The list of object files may include archives.
1520 At least one object file must be given.
1522 @code{strip} modifies the files named in its argument,
1523 rather than writing modified copies under different names.
1526 @item -F @var{bfdname}
1527 @itemx --target=@var{bfdname}
1528 Treat the original @var{objfile} as a file with the object
1529 code format @var{bfdname}, and rewrite it in the same format.
1530 @xref{Target Selection}, for more information.
1533 Show a summary of the options to @code{strip} and exit.
1535 @item -I @var{bfdname}
1536 @itemx --input-target=@var{bfdname}
1537 Treat the original @var{objfile} as a file with the object
1538 code format @var{bfdname}.
1539 @xref{Target Selection}, for more information.
1541 @item -O @var{bfdname}
1542 @itemx --output-target=@var{bfdname}
1543 Replace @var{objfile} with a file in the output format @var{bfdname}.
1544 @xref{Target Selection}, for more information.
1546 @item -R @var{sectionname}
1547 @itemx --remove-section=@var{sectionname}
1548 Remove any section named @var{sectionname} from the output file. This
1549 option may be given more than once. Note that using this option
1550 inappropriately may make the output file unusable.
1558 @itemx --strip-debug
1559 Remove debugging symbols only.
1561 @item --strip-unneeded
1562 Remove all symbols that are not needed for relocation processing.
1564 @item -K @var{symbolname}
1565 @itemx --keep-symbol=@var{symbolname}
1566 Keep only symbol @var{symbolname} from the source file. This option may
1567 be given more than once.
1569 @item -N @var{symbolname}
1570 @itemx --strip-symbol=@var{symbolname}
1571 Remove symbol @var{symbolname} from the source file. This option may be
1572 given more than once, and may be combined with strip options other than
1576 Put the stripped output in @var{file}, rather than replacing the
1577 existing file. When this argument is used, only one @var{objfile}
1578 argument may be specified.
1581 @itemx --preserve-dates
1582 Preserve the access and modification dates of the file.
1585 @itemx --discard-all
1586 Remove non-global symbols.
1589 @itemx --discard-locals
1590 Remove compiler-generated local symbols.
1591 (These usually start with @samp{L} or @samp{.}.)
1595 Show the version number for @code{strip}.
1599 Verbose output: list all object files modified. In the case of
1600 archives, @samp{strip -v} lists all members of the archive.
1607 @cindex demangling C++ symbols
1610 c++filt [ -_ | --strip-underscores ]
1611 [ -n | --no-strip-underscores ]
1612 [ -s @var{format} | --format=@var{format} ]
1613 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1616 The C++ language provides function overloading, which means that you can
1617 write many functions with the same name (providing each takes parameters
1618 of different types). All C++ function names are encoded into a
1619 low-level assembly label (this process is known as
1620 @dfn{mangling}). The @code{c++filt} program does the inverse mapping: it
1621 decodes (@dfn{demangles}) low-level names into user-level names so that
1622 the linker can keep these overloaded functions from clashing.
1624 Every alphanumeric word (consisting of letters, digits, underscores,
1625 dollars, or periods) seen in the input is a potential label. If the
1626 label decodes into a C++ name, the C++ name replaces the low-level
1629 You can use @code{c++filt} to decipher individual symbols:
1632 c++filt @var{symbol}
1635 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1636 names from the standard input and writes the demangled names to the
1637 standard output. All results are printed on the standard output.
1641 @itemx --strip-underscores
1642 On some systems, both the C and C++ compilers put an underscore in front
1643 of every name. For example, the C name @code{foo} gets the low-level
1644 name @code{_foo}. This option removes the initial underscore. Whether
1645 @code{c++filt} removes the underscore by default is target dependent.
1648 @itemx --no-strip-underscores
1649 Do not remove the initial underscore.
1651 @item -s @var{format}
1652 @itemx --format=@var{format}
1653 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1654 different C++ compilers. The argument to this option selects which
1659 the one used by the @sc{gnu} compiler (the default method)
1661 the one used by the Lucid compiler
1663 the one specified by the C++ Annotated Reference Manual
1667 Print a summary of the options to @code{c++filt} and exit.
1670 Print the version number of @code{c++filt} and exit.
1674 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1675 user interface are subject to change in future releases. In particular,
1676 a command-line option may be required in the the future to decode a name
1677 passed as an argument on the command line; in other words,
1680 c++filt @var{symbol}
1684 may in a future release become
1687 c++filt @var{option} @var{symbol}
1695 @cindex address to file name and line number
1698 addr2line [ -b @var{bfdname} | --target=@var{bfdname} ]
1700 [ -e @var{filename} | --exe=@var{filename} ]
1701 [ -f | --functions ] [ -s | --basename ]
1702 [ -H | --help ] [ -V | --version ]
1706 @code{addr2line} translates program addresses into file names and line
1707 numbers. Given an address and an executable, it uses the debugging
1708 information in the executable to figure out which file name and line
1709 number are associated with a given address.
1711 The executable to use is specified with the @code{-e} option. The
1712 default is @file{a.out}.
1714 @code{addr2line} has two modes of operation.
1716 In the first, hexadecimal addresses are specified on the command line,
1717 and @code{addr2line} displays the file name and line number for each
1720 In the second, @code{addr2line} reads hexadecimal addresses from
1721 standard input, and prints the file name and line number for each
1722 address on standard output. In this mode, @code{addr2line} may be used
1723 in a pipe to convert dynamically chosen addresses.
1725 The format of the output is @samp{FILENAME:LINENO}. The file name and
1726 line number for each address is printed on a separate line. If the
1727 @code{-f} option is used, then each @samp{FILENAME:LINENO} line is
1728 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
1729 containing the address.
1731 If the file name or function name can not be determined,
1732 @code{addr2line} will print two question marks in their place. If the
1733 line number can not be determined, @code{addr2line} will print 0.
1735 The long and short forms of options, shown here as alternatives, are
1739 @item -b @var{bfdname}
1740 @itemx --target=@var{bfdname}
1741 @cindex object code format
1742 Specify that the object-code format for the object files is
1747 @cindex demangling in objdump
1748 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1749 Besides removing any initial underscore prepended by the system, this
1750 makes C++ function names readable. @xref{c++filt}, for more information
1753 @item -e @var{filename}
1754 @itemx --exe=@var{filename}
1755 Specify the name of the executable for which addresses should be
1756 translated. The default file is @file{a.out}.
1760 Display function names as well as file and line number information.
1764 Display only the base of each file name.
1770 @code{nlmconv} converts a relocatable object file into a NetWare
1774 @code{nlmconv} currently works with @samp{i386} object
1775 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1776 object files in @sc{elf}, or @code{a.out} format@footnote{
1777 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1778 format in the Binary File Descriptor library. It has only been tested
1779 with the above formats.}.
1783 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1784 utilities, since it is only useful for NLM targets.
1788 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1789 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1790 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1791 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1792 [ -h | --help ] [ -V | --version ]
1793 @var{infile} @var{outfile}
1796 @code{nlmconv} converts the relocatable @samp{i386} object file
1797 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1798 reading @var{headerfile} for NLM header information. For instructions
1799 on writing the NLM command file language used in header files, see the
1800 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1801 Development and Tools Overview}, which is part of the NLM Software
1802 Developer's Kit (``NLM SDK''), available from Novell, Inc.
1803 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
1804 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
1807 @code{nlmconv} can perform a link step. In other words, you can list
1808 more than one object file for input if you list them in the definitions
1809 file (rather than simply specifying one input file on the command line).
1810 In this case, @code{nlmconv} calls the linker for you.
1813 @item -I @var{bfdname}
1814 @itemx --input-target=@var{bfdname}
1815 Object format of the input file. @code{nlmconv} can usually determine
1816 the format of a given file (so no default is necessary).
1817 @xref{Target Selection}, for more information.
1819 @item -O @var{bfdname}
1820 @itemx --output-target=@var{bfdname}
1821 Object format of the output file. @code{nlmconv} infers the output
1822 format based on the input format, e.g. for a @samp{i386} input file the
1823 output format is @samp{nlm32-i386}.
1824 @xref{Target Selection}, for more information.
1826 @item -T @var{headerfile}
1827 @itemx --header-file=@var{headerfile}
1828 Reads @var{headerfile} for NLM header information. For instructions on
1829 writing the NLM command file language used in header files, see@ see the
1830 @samp{linkers} section, of the @cite{NLM Development and Tools
1831 Overview}, which is part of the NLM Software Developer's Kit, available
1836 Displays (on standard error) the linker command line used by @code{nlmconv}.
1838 @item -l @var{linker}
1839 @itemx --linker=@var{linker}
1840 Use @var{linker} for any linking. @var{linker} can be an abosolute or a
1845 Prints a usage summary.
1849 Prints the version number for @code{nlmconv}.
1852 @node Selecting The Target System
1853 @chapter Selecting the target system
1855 You can specify three aspects of the target system to the @sc{gnu}
1856 binary file utilities, each in several ways:
1866 the linker emulation (which applies to the linker only)
1869 In the following summaries, the lists of ways to specify values are in
1870 order of decreasing precedence. The ways listed first override those
1873 The commands to list valid values only list the values for which the
1874 programs you are running were configured. If they were configured with
1875 @samp{--enable-targets=all}, the commands list most of the available
1876 values, but a few are left out; not all targets can be configured in at
1877 once because some of them can only be configured @dfn{native} (on hosts
1878 with the same type as the target system).
1881 * Target Selection::
1882 * Architecture Selection::
1883 * Linker Emulation Selection::
1886 @node Target Selection
1887 @section Target Selection
1889 A @dfn{target} is an object file format. A given target may be
1890 supported for multiple architectures (@pxref{Architecture Selection}).
1891 A target selection may also have variations for different operating
1892 systems or architectures.
1894 The command to list valid target values is @samp{objdump -i}
1895 (the first column of output contains the relevant information).
1897 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
1898 @samp{a.out-sunos-big}.
1900 You can also specify a target using a configuration triplet. This is
1901 the same sort of name that is passed to configure to specify a target.
1902 When you use a configuration triplet as an argument, it must be fully
1903 canonicalized. You can see the canonical version of a triplet by
1904 running the shell script @file{config.sub} which is included with the
1907 Some sample configuration triplets are: @samp{m68k-hp-bsd},
1908 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
1910 @subheading @code{objdump} Target
1916 command line option: @samp{-b} or @samp{--target}
1919 environment variable @code{GNUTARGET}
1922 deduced from the input file
1925 @subheading @code{objcopy} and @code{strip} Input Target
1931 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
1934 environment variable @code{GNUTARGET}
1937 deduced from the input file
1940 @subheading @code{objcopy} and @code{strip} Output Target
1946 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
1949 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
1952 environment variable @code{GNUTARGET}
1955 deduced from the input file
1958 @subheading @code{nm}, @code{size}, and @code{strings} Target
1964 command line option: @samp{--target}
1967 environment variable @code{GNUTARGET}
1970 deduced from the input file
1973 @subheading Linker Input Target
1979 command line option: @samp{-b} or @samp{--format}
1980 (@pxref{Options,,Options,ld.info,Using LD})
1983 script command @code{TARGET}
1984 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
1987 environment variable @code{GNUTARGET}
1988 (@pxref{Environment,,Environment,ld.info,Using LD})
1991 the default target of the selected linker emulation
1992 (@pxref{Linker Emulation Selection})
1995 @subheading Linker Output Target
2001 command line option: @samp{-oformat}
2002 (@pxref{Options,,Options,ld.info,Using LD})
2005 script command @code{OUTPUT_FORMAT}
2006 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2009 the linker input target (see ``Linker Input Target'' above)
2012 @node Architecture Selection
2013 @section Architecture selection
2015 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
2016 to run. Its name may contain a colon, separating the name of the
2017 processor family from the name of the particular @sc{cpu}.
2019 The command to list valid architecture values is @samp{objdump -i} (the
2020 second column contains the relevant information).
2022 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
2024 @subheading @code{objdump} Architecture
2030 command line option: @samp{-m} or @samp{--architecture}
2033 deduced from the input file
2036 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
2042 deduced from the input file
2045 @subheading Linker Input Architecture
2051 deduced from the input file
2054 @subheading Linker Output Architecture
2060 script command @code{OUTPUT_ARCH}
2061 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2064 the default architecture from the linker output target
2065 (@pxref{Target Selection})
2068 @node Linker Emulation Selection
2069 @section Linker emulation selection
2071 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
2072 the linker default values for the other aspects of the target system.
2073 In particular, it consists of
2083 several ``hook'' functions that are run at certain stages of the linking
2084 process to do special things that some targets require
2087 The command to list valid linker emulation values is @samp{ld -V}.
2089 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
2095 command line option: @samp{-m}
2096 (@pxref{Options,,Options,ld.info,Using LD})
2099 environment variable @code{LDEMULATION}
2102 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
2103 which comes from @code{EMUL} in @file{config/@var{target}.mt}
2106 @node Reporting Bugs
2107 @chapter Reporting Bugs
2109 @cindex reporting bugs
2111 Your bug reports play an essential role in making the binary utilities
2114 Reporting a bug may help you by bringing a solution to your problem, or
2115 it may not. But in any case the principal function of a bug report is
2116 to help the entire community by making the next version of the binary
2117 utilities work better. Bug reports are your contribution to their
2120 In order for a bug report to serve its purpose, you must include the
2121 information that enables us to fix the bug.
2124 * Bug Criteria:: Have you found a bug?
2125 * Bug Reporting:: How to report bugs
2129 @section Have you found a bug?
2130 @cindex bug criteria
2132 If you are not sure whether you have found a bug, here are some guidelines:
2135 @cindex fatal signal
2138 If a binary utility gets a fatal signal, for any input whatever, that is
2139 a bug. Reliable utilities never crash.
2141 @cindex error on valid input
2143 If a binary utility produces an error message for valid input, that is a
2147 If you are an experienced user of binary utilities, your suggestions for
2148 improvement are welcome in any case.
2152 @section How to report bugs
2154 @cindex bugs, reporting
2156 A number of companies and individuals offer support for @sc{gnu}
2157 products. If you obtained the binary utilities from a support
2158 organization, we recommend you contact that organization first.
2160 You can find contact information for many support companies and
2161 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2164 In any event, we also recommend that you send bug reports for the binary
2165 utilities to @samp{bug-gnu-utils@@prep.ai.mit.edu}.
2167 The fundamental principle of reporting bugs usefully is this:
2168 @strong{report all the facts}. If you are not sure whether to state a
2169 fact or leave it out, state it!
2171 Often people omit facts because they think they know what causes the
2172 problem and assume that some details do not matter. Thus, you might
2173 assume that the name of a file you use in an example does not matter.
2174 Well, probably it does not, but one cannot be sure. Perhaps the bug is
2175 a stray memory reference which happens to fetch from the location where
2176 that pathname is stored in memory; perhaps, if the pathname were
2177 different, the contents of that location would fool the utility into
2178 doing the right thing despite the bug. Play it safe and give a
2179 specific, complete example. That is the easiest thing for you to do,
2180 and the most helpful.
2182 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2183 it is new to us. Therefore, always write your bug reports on the assumption
2184 that the bug has not been reported previously.
2186 Sometimes people give a few sketchy facts and ask, ``Does this ring a
2187 bell?'' Those bug reports are useless, and we urge everyone to
2188 @emph{refuse to respond to them} except to chide the sender to report
2191 To enable us to fix the bug, you should include all these things:
2195 The version of the utility. Each utility announces it if you start it
2196 with the @samp{--version} argument.
2198 Without this, we will not know whether there is any point in looking for
2199 the bug in the current version of the binary utilities.
2202 Any patches you may have applied to the source, including any patches
2203 made to the @code{BFD} library.
2206 The type of machine you are using, and the operating system name and
2210 What compiler (and its version) was used to compile the utilities---e.g.
2214 The command arguments you gave the utility to observe the bug. To
2215 guarantee you will not omit something important, list them all. A copy
2216 of the Makefile (or the output from make) is sufficient.
2218 If we were to try to guess the arguments, we would probably guess wrong
2219 and then we might not encounter the bug.
2222 A complete input file, or set of input files, that will reproduce the
2223 bug. If the utility is reading an object file or files, then it is
2224 generally most helpful to send the actual object files, uuencoded if
2225 necessary to get them through the mail system. Making them available
2226 for anonymous FTP is not as good, but may be the only reasonable choice
2227 for large object files.
2229 If the source files were produced exclusively using @sc{gnu} programs
2230 (e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2231 may be OK to send the source files rather than the object files. In
2232 this case, be sure to say exactly what version of @code{gcc}, or
2233 whatever, was used to produce the object files. Also say how
2234 @code{gcc}, or whatever, was configured.
2237 A description of what behavior you observe that you believe is
2238 incorrect. For example, ``It gets a fatal signal.''
2240 Of course, if the bug is that the utility gets a fatal signal, then we
2241 will certainly notice it. But if the bug is incorrect output, we might
2242 not notice unless it is glaringly wrong. You might as well not give us
2243 a chance to make a mistake.
2245 Even if the problem you experience is a fatal signal, you should still
2246 say so explicitly. Suppose something strange is going on, such as, your
2247 copy of the utility is out of synch, or you have encountered a bug in
2248 the C library on your system. (This has happened!) Your copy might
2249 crash and ours would not. If you told us to expect a crash, then when
2250 ours fails to crash, we would know that the bug was not happening for
2251 us. If you had not told us to expect a crash, then we would not be able
2252 to draw any conclusion from our observations.
2255 If you wish to suggest changes to the source, send us context diffs, as
2256 generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2257 option. Always send diffs from the old file to the new file. If you
2258 even discuss something in the @code{ld} source, refer to it by context,
2261 The line numbers in our development sources will not match those in your
2262 sources. Your line numbers would convey no useful information to us.
2265 Here are some things that are not necessary:
2269 A description of the envelope of the bug.
2271 Often people who encounter a bug spend a lot of time investigating
2272 which changes to the input file will make the bug go away and which
2273 changes will not affect it.
2275 This is often time consuming and not very useful, because the way we
2276 will find the bug is by running a single example under the debugger
2277 with breakpoints, not by pure deduction from a series of examples.
2278 We recommend that you save your time for something else.
2280 Of course, if you can find a simpler example to report @emph{instead}
2281 of the original one, that is a convenience for us. Errors in the
2282 output will be easier to spot, running under the debugger will take
2283 less time, and so on.
2285 However, simplification is not vital; if you do not want to do this,
2286 report the bug anyway and send us the entire test case you used.
2289 A patch for the bug.
2291 A patch for the bug does help us if it is a good one. But do not omit
2292 the necessary information, such as the test case, on the assumption that
2293 a patch is all we need. We might see problems with your patch and decide
2294 to fix the problem another way, or we might not understand it at all.
2296 Sometimes with programs as complicated as the binary utilities it is
2297 very hard to construct an example that will make the program follow a
2298 certain path through the code. If you do not send us the example, we
2299 will not be able to construct one, so we will not be able to verify that
2302 And if we cannot understand what bug you are trying to fix, or why your
2303 patch should be an improvement, we will not install it. A test case will
2304 help us to understand.
2307 A guess about what the bug is or what it depends on.
2309 Such guesses are usually wrong. Even we cannot guess right about such
2310 things without first using the debugger to find the facts.