1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
8 * Binutils: (binutils). The GNU binary utilities "ar", "objcopy",
9 "objdump", "nm", "nlmconv", "size", "readelf"
10 "strings", "strip", "ranlib" and "dlltool".
16 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 1999 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", "readelf" and "ranlib".
44 @c Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 1999 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, 97, 1998 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 Display the contents of ELF format files.
112 List file section sizes and total size
115 List printable strings from files
121 Demangle encoded C++ symbols (on MS-DOS, this program is named
125 Convert addresses into file names and line numbers
128 Convert object code into a Netware Loadable Module
131 Manipulate Windows resources
134 Create the files needed to build and use Dynamic Link Libraries
139 * ar:: Create, modify, and extract from archives
140 * nm:: List symbols from object files
141 * objcopy:: Copy and translate object files
142 * objdump:: Display information from object files
143 * ranlib:: Generate index to archive contents
144 * readelf:: Display the contents of ELF format files.
145 * size:: List section sizes and total size
146 * strings:: List printable strings from files
147 * strip:: Discard symbols
148 * c++filt:: Filter to demangle encoded C++ symbols
149 * cxxfilt: c++filt. MS-DOS name for c++filt
150 * addr2line:: Convert addresses to file and line
151 * nlmconv:: Converts object code into an NLM
152 * windres:: Manipulate Windows resources
153 * dlltool:: Create files needed to build and use DLLs
154 * Selecting The Target System:: How these utilities determine the target.
155 * Reporting Bugs:: Reporting Bugs
164 @cindex collections of files
166 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
167 ar -M [ <mri-script ]
170 The @sc{gnu} @code{ar} program creates, modifies, and extracts from
171 archives. An @dfn{archive} is a single file holding a collection of
172 other files in a structure that makes it possible to retrieve
173 the original individual files (called @dfn{members} of the archive).
175 The original files' contents, mode (permissions), timestamp, owner, and
176 group are preserved in the archive, and can be restored on
180 @sc{gnu} @code{ar} can maintain archives whose members have names of any
181 length; however, depending on how @code{ar} is configured on your
182 system, a limit on member-name length may be imposed for compatibility
183 with archive formats maintained with other tools. If it exists, the
184 limit is often 15 characters (typical of formats related to a.out) or 16
185 characters (typical of formats related to coff).
188 @code{ar} is considered a binary utility because archives of this sort
189 are most often used as @dfn{libraries} holding commonly needed
193 @code{ar} creates an index to the symbols defined in relocatable
194 object modules in the archive when you specify the modifier @samp{s}.
195 Once created, this index is updated in the archive whenever @code{ar}
196 makes a change to its contents (save for the @samp{q} update operation).
197 An archive with such an index speeds up linking to the library, and
198 allows routines in the library to call each other without regard to
199 their placement in the archive.
201 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
202 table. If an archive lacks the table, another form of @code{ar} called
203 @code{ranlib} can be used to add just the table.
205 @cindex compatibility, @code{ar}
206 @cindex @code{ar} compatibility
207 @sc{gnu} @code{ar} is designed to be compatible with two different
208 facilities. You can control its activity using command-line options,
209 like the different varieties of @code{ar} on Unix systems; or, if you
210 specify the single command-line option @samp{-M}, you can control it
211 with a script supplied via standard input, like the MRI ``librarian''
215 * ar cmdline:: Controlling @code{ar} on the command line
216 * ar scripts:: Controlling @code{ar} with a script
221 @section Controlling @code{ar} on the command line
224 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
227 @cindex Unix compatibility, @code{ar}
228 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
229 arguments to execute: one keyletter specifying the @emph{operation}
230 (optionally accompanied by other keyletters specifying
231 @emph{modifiers}), and the archive name to act on.
233 Most operations can also accept further @var{member} arguments,
234 specifying particular files to operate on.
236 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
237 flags @var{mod} in any order, within the first command-line argument.
239 If you wish, you may begin the first command-line argument with a
242 @cindex operations on archive
243 The @var{p} keyletter specifies what operation to execute; it may be
244 any of the following, but you must specify only one of them:
248 @cindex deleting from archive
249 @emph{Delete} modules from the archive. Specify the names of modules to
250 be deleted as @var{member}@dots{}; the archive is untouched if you
251 specify no files to delete.
253 If you specify the @samp{v} modifier, @code{ar} lists each module
257 @cindex moving in archive
258 Use this operation to @emph{move} members in an archive.
260 The ordering of members in an archive can make a difference in how
261 programs are linked using the library, if a symbol is defined in more
264 If no modifiers are used with @code{m}, any members you name in the
265 @var{member} arguments are moved to the @emph{end} of the archive;
266 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
267 specified place instead.
270 @cindex printing from archive
271 @emph{Print} the specified members of the archive, to the standard
272 output file. If the @samp{v} modifier is specified, show the member
273 name before copying its contents to standard output.
275 If you specify no @var{member} arguments, all the files in the archive are
279 @cindex quick append to archive
280 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
281 @var{archive}, without checking for replacement.
283 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
284 operation; new members are always placed at the end of the archive.
286 The modifier @samp{v} makes @code{ar} list each file as it is appended.
288 Since the point of this operation is speed, the archive's symbol table
289 index is not updated, even if it already existed; you can use @samp{ar s} or
290 @code{ranlib} explicitly to update the symbol table index.
292 However, too many different systems assume quick append rebuilds the
293 index, so GNU ar implements @code{q} as a synonym for @code{r}.
296 @cindex replacement in archive
297 Insert the files @var{member}@dots{} into @var{archive} (with
298 @emph{replacement}). This operation differs from @samp{q} in that any
299 previously existing members are deleted if their names match those being
302 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
303 displays an error message, and leaves undisturbed any existing members
304 of the archive matching that name.
306 By default, new members are added at the end of the file; but you may
307 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
308 placement relative to some existing member.
310 The modifier @samp{v} used with this operation elicits a line of
311 output for each file inserted, along with one of the letters @samp{a} or
312 @samp{r} to indicate whether the file was appended (no old member
313 deleted) or replaced.
316 @cindex contents of archive
317 Display a @emph{table} listing the contents of @var{archive}, or those
318 of the files listed in @var{member}@dots{} that are present in the
319 archive. Normally only the member name is shown; if you also want to
320 see the modes (permissions), timestamp, owner, group, and size, you can
321 request that by also specifying the @samp{v} modifier.
323 If you do not specify a @var{member}, all files in the archive
326 @cindex repeated names in archive
327 @cindex name duplication in archive
328 If there is more than one file with the same name (say, @samp{fie}) in
329 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
330 first instance; to see them all, you must ask for a complete
331 listing---in our example, @samp{ar t b.a}.
332 @c WRS only; per Gumby, this is implementation-dependent, and in a more
333 @c recent case in fact works the other way.
336 @cindex extract from archive
337 @emph{Extract} members (named @var{member}) from the archive. You can
338 use the @samp{v} modifier with this operation, to request that
339 @code{ar} list each name as it extracts it.
341 If you do not specify a @var{member}, all files in the archive
346 A number of modifiers (@var{mod}) may immediately follow the @var{p}
347 keyletter, to specify variations on an operation's behavior:
351 @cindex relative placement in archive
352 Add new files @emph{after} an existing member of the
353 archive. If you use the modifier @samp{a}, the name of an existing archive
354 member must be present as the @var{relpos} argument, before the
355 @var{archive} specification.
358 Add new files @emph{before} an existing member of the
359 archive. If you use the modifier @samp{b}, the name of an existing archive
360 member must be present as the @var{relpos} argument, before the
361 @var{archive} specification. (same as @samp{i}).
364 @cindex creating archives
365 @emph{Create} the archive. The specified @var{archive} is always
366 created if it did not exist, when you request an update. But a warning is
367 issued unless you specify in advance that you expect to create it, by
371 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
372 names of any length. This will cause it to create archives which are
373 not compatible with the native @code{ar} program on some systems. If
374 this is a concern, the @samp{f} modifier may be used to truncate file
375 names when putting them in the archive.
378 Insert new files @emph{before} an existing member of the
379 archive. If you use the modifier @samp{i}, the name of an existing archive
380 member must be present as the @var{relpos} argument, before the
381 @var{archive} specification. (same as @samp{b}).
384 This modifier is accepted but not used.
385 @c whaffor ar l modifier??? presumably compat; with
386 @c what???---doc@@cygnus.com, 25jan91
389 @cindex dates in archive
390 Preserve the @emph{original} dates of members when extracting them. If
391 you do not specify this modifier, files extracted from the archive
392 are stamped with the time of extraction.
395 @cindex writing archive index
396 Write an object-file index into the archive, or update an existing one,
397 even if no other change is made to the archive. You may use this modifier
398 flag either with any operation, or alone. Running @samp{ar s} on an
399 archive is equivalent to running @samp{ranlib} on it.
402 @cindex not writing archive index
403 Do not generate an archive symbol table. This can speed up building a
404 large library in several steps. The resulting archive can not be used
405 with the linker. In order to build a symbol table, you must omit the
406 @samp{S} modifier on the last execution of @samp{ar}, or you must run
407 @samp{ranlib} on the archive.
410 @cindex updating an archive
411 Normally, @samp{ar r}@dots{} inserts all files
412 listed into the archive. If you would like to insert @emph{only} those
413 of the files you list that are newer than existing members of the same
414 names, use this modifier. The @samp{u} modifier is allowed only for the
415 operation @samp{r} (replace). In particular, the combination @samp{qu} is
416 not allowed, since checking the timestamps would lose any speed
417 advantage from the operation @samp{q}.
420 This modifier requests the @emph{verbose} version of an operation. Many
421 operations display additional information, such as filenames processed,
422 when the modifier @samp{v} is appended.
425 This modifier shows the version number of @code{ar}.
429 @section Controlling @code{ar} with a script
432 ar -M [ <@var{script} ]
435 @cindex MRI compatibility, @code{ar}
436 @cindex scripts, @code{ar}
437 If you use the single command-line option @samp{-M} with @code{ar}, you
438 can control its operation with a rudimentary command language. This
439 form of @code{ar} operates interactively if standard input is coming
440 directly from a terminal. During interactive use, @code{ar} prompts for
441 input (the prompt is @samp{AR >}), and continues executing even after
442 errors. If you redirect standard input to a script file, no prompts are
443 issued, and @code{ar} abandons execution (with a nonzero exit code)
446 The @code{ar} command language is @emph{not} designed to be equivalent
447 to the command-line options; in fact, it provides somewhat less control
448 over archives. The only purpose of the command language is to ease the
449 transition to @sc{gnu} @code{ar} for developers who already have scripts
450 written for the MRI ``librarian'' program.
452 The syntax for the @code{ar} command language is straightforward:
455 commands are recognized in upper or lower case; for example, @code{LIST}
456 is the same as @code{list}. In the following descriptions, commands are
457 shown in upper case for clarity.
460 a single command may appear on each line; it is the first word on the
464 empty lines are allowed, and have no effect.
467 comments are allowed; text after either of the characters @samp{*}
468 or @samp{;} is ignored.
471 Whenever you use a list of names as part of the argument to an @code{ar}
472 command, you can separate the individual names with either commas or
473 blanks. Commas are shown in the explanations below, for clarity.
476 @samp{+} is used as a line continuation character; if @samp{+} appears
477 at the end of a line, the text on the following line is considered part
478 of the current command.
481 Here are the commands you can use in @code{ar} scripts, or when using
482 @code{ar} interactively. Three of them have special significance:
484 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
485 a temporary file required for most of the other commands.
487 @code{SAVE} commits the changes so far specified by the script. Prior
488 to @code{SAVE}, commands affect only the temporary copy of the current
492 @item ADDLIB @var{archive}
493 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
494 Add all the contents of @var{archive} (or, if specified, each named
495 @var{module} from @var{archive}) to the current archive.
497 Requires prior use of @code{OPEN} or @code{CREATE}.
499 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
500 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
501 @c else like "ar q..."
502 Add each named @var{member} as a module in the current archive.
504 Requires prior use of @code{OPEN} or @code{CREATE}.
507 Discard the contents of the current archive, canceling the effect of
508 any operations since the last @code{SAVE}. May be executed (with no
509 effect) even if no current archive is specified.
511 @item CREATE @var{archive}
512 Creates an archive, and makes it the current archive (required for many
513 other commands). The new archive is created with a temporary name; it
514 is not actually saved as @var{archive} until you use @code{SAVE}.
515 You can overwrite existing archives; similarly, the contents of any
516 existing file named @var{archive} will not be destroyed until @code{SAVE}.
518 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
519 Delete each listed @var{module} from the current archive; equivalent to
520 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
522 Requires prior use of @code{OPEN} or @code{CREATE}.
524 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
525 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
526 List each named @var{module} present in @var{archive}. The separate
527 command @code{VERBOSE} specifies the form of the output: when verbose
528 output is off, output is like that of @samp{ar -t @var{archive}
529 @var{module}@dots{}}. When verbose output is on, the listing is like
530 @samp{ar -tv @var{archive} @var{module}@dots{}}.
532 Output normally goes to the standard output stream; however, if you
533 specify @var{outputfile} as a final argument, @code{ar} directs the
537 Exit from @code{ar}, with a @code{0} exit code to indicate successful
538 completion. This command does not save the output file; if you have
539 changed the current archive since the last @code{SAVE} command, those
542 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
543 Extract each named @var{module} from the current archive, writing them
544 into the current directory as separate files. Equivalent to @samp{ar -x
545 @var{archive} @var{module}@dots{}}.
547 Requires prior use of @code{OPEN} or @code{CREATE}.
550 @c FIXME Tokens but no commands???
557 Display full contents of the current archive, in ``verbose'' style
558 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
559 tv @var{archive}}. (This single command is a @sc{gnu} @code{ar}
560 enhancement, rather than present for MRI compatibility.)
562 Requires prior use of @code{OPEN} or @code{CREATE}.
564 @item OPEN @var{archive}
565 Opens an existing archive for use as the current archive (required for
566 many other commands). Any changes as the result of subsequent commands
567 will not actually affect @var{archive} until you next use @code{SAVE}.
569 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
570 In the current archive, replace each existing @var{module} (named in
571 the @code{REPLACE} arguments) from files in the current working directory.
572 To execute this command without errors, both the file, and the module in
573 the current archive, must exist.
575 Requires prior use of @code{OPEN} or @code{CREATE}.
578 Toggle an internal flag governing the output from @code{DIRECTORY}.
579 When the flag is on, @code{DIRECTORY} output matches output from
580 @samp{ar -tv }@dots{}.
583 Commit your changes to the current archive, and actually save it as a
584 file with the name specified in the last @code{CREATE} or @code{OPEN}
587 Requires prior use of @code{OPEN} or @code{CREATE}.
596 The @sc{gnu} linker @code{ld} is now described in a separate manual.
597 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
606 nm [ -a | --debug-syms ] [ -g | --extern-only ]
607 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
608 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
609 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
610 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
611 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
612 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
613 [ --defined-only ] [-l | --line-numbers ]
614 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
617 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
618 If no object files are listed as arguments, @code{nm} assumes
621 For each symbol, @code{nm} shows:
625 The symbol value, in the radix selected by options (see below), or
626 hexadecimal by default.
629 The symbol type. At least the following types are used; others are, as
630 well, depending on the object file format. If lowercase, the symbol is
631 local; if uppercase, the symbol is global (external).
633 @c Some more detail on exactly what these symbol types are used for
637 The symbol's value is absolute, and will not be changed by further
641 The symbol is in the uninitialized data section (known as BSS).
644 The symbol is common. Common symbols are uninitialized data. When
645 linking, multiple common symbols may appear with the same name. If the
646 symbol is defined anywhere, the common symbols are treated as undefined
647 references. For more details on common symbols, see the discussion of
648 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
651 The symbol is in the initialized data section.
654 The symbol is in an initialized data section for small objects. Some
655 object file formats permit more efficient access to small data objects,
656 such as a global int variable as opposed to a large global array.
659 The symbol is an indirect reference to another symbol. This is a GNU
660 extension to the a.out object file format which is rarely used.
663 The symbol is a debugging symbol.
666 The symbol is in a read only data section.
669 The symbol is in an uninitialized data section for small objects.
672 The symbol is in the text (code) section.
675 The symbol is undefined.
678 The symbol is weak. When a weak defined symbol is linked with a normal
679 defined symbol, the normal defined symbol is used with no error. When a
680 weak undefined symbol is linked and the symbol is not defined, the value
681 of the weak symbol becomes zero with no error.
684 The symbol is a stabs symbol in an a.out object file. In this case, the
685 next values printed are the stabs other field, the stabs desc field, and
686 the stab type. Stabs symbols are used to hold debugging information;
687 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
688 ``stabs'' debug format}.
691 The symbol type is unknown, or object file format specific.
698 The long and short forms of options, shown here as alternatives, are
704 @itemx --print-file-name
705 @cindex input file name
707 @cindex source file name
708 Precede each symbol by the name of the input file (or archive element)
709 in which it was found, rather than identifying the input file once only,
710 before all of its symbols.
714 @cindex debugging symbols
715 Display all symbols, even debugger-only symbols; normally these are not
719 @cindex @code{nm} format
720 @cindex @code{nm} compatibility
721 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
725 @cindex demangling in nm
726 Decode (@dfn{demangle}) low-level symbol names into user-level names.
727 Besides removing any initial underscore prepended by the system, this
728 makes C++ function names readable. @xref{c++filt}, for more information
732 Do not demangle low-level symbol names. This is the default.
736 @cindex dynamic symbols
737 Display the dynamic symbols rather than the normal symbols. This is
738 only meaningful for dynamic objects, such as certain types of shared
741 @item -f @var{format}
742 @itemx --format=@var{format}
743 @cindex @code{nm} format
744 @cindex @code{nm} compatibility
745 Use the output format @var{format}, which can be @code{bsd},
746 @code{sysv}, or @code{posix}. The default is @code{bsd}.
747 Only the first character of @var{format} is significant; it can be
748 either upper or lower case.
752 @cindex external symbols
753 Display only external symbols.
756 @itemx --line-numbers
757 @cindex symbol line numbers
758 For each symbol, use debugging information to try to find a filename and
759 line number. For a defined symbol, look for the line number of the
760 address of the symbol. For an undefined symbol, look for the line
761 number of a relocation entry which refers to the symbol. If line number
762 information can be found, print it after the other symbol information.
766 @itemx --numeric-sort
767 Sort symbols numerically by their addresses, rather than alphabetically
772 @cindex sorting symbols
773 Do not bother to sort the symbols in any order; print them in the order
778 Use the POSIX.2 standard output format instead of the default format.
779 Equivalent to @samp{-f posix}.
783 @cindex symbol index, listing
784 When listing symbols from archive members, include the index: a mapping
785 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
786 contain definitions for which names.
789 @itemx --reverse-sort
790 Reverse the order of the sort (whether numeric or alphabetic); let the
794 Sort symbols by size. The size is computed as the difference between
795 the value of the symbol and the value of the symbol with the next higher
796 value. The size of the symbol is printed, rather than the value.
799 @itemx --radix=@var{radix}
800 Use @var{radix} as the radix for printing the symbol values. It must be
801 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
803 @item --target=@var{bfdname}
804 @cindex object code format
805 Specify an object code format other than your system's default format.
806 @xref{Target Selection}, for more information.
809 @itemx --undefined-only
810 @cindex external symbols
811 @cindex undefined symbols
812 Display only undefined symbols (those external to each object file).
815 @cindex external symbols
816 @cindex undefined symbols
817 Display only defined symbols for each object file.
821 Show the version number of @code{nm} and exit.
824 Show a summary of the options to @code{nm} and exit.
831 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
832 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
833 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
834 [ -S | --strip-all ] [ -g | --strip-debug ]
835 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
836 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
837 [ -L @var{symbolname} | --localize-symbol=@var{symbolname} ]
838 [ -W @var{symbolname} | --weaken-symbol=@var{symbolname} ]
839 [ -x | --discard-all ] [ -X | --discard-locals ]
840 [ -b @var{byte} | --byte=@var{byte} ]
841 [ -i @var{interleave} | --interleave=@var{interleave} ]
842 [ -j @var{sectionname} | --only-section=@var{sectionname} ]
843 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
844 [ -p | --preserve-dates ] [ --debugging ]
845 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
846 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
847 [ --change-addresses=@var{incr} ]
848 [ --change-section-address=@var{section}@{=,+,-@}@var{val} ]
849 [ --change-section-lma=@var{section}@{=,+,-@}@var{val} ]
850 [ --change-section-vma=@var{section}@{=,+,-@}@var{val} ]
851 [ --change-warnings ] [ --no-change-warnings ]
852 [ --set-section-flags=@var{section}=@var{flags} ]
853 [ --add-section=@var{sectionname}=@var{filename} ]
854 [ --change-leading-char ] [ --remove-leading-char ]
856 [ -v | --verbose ] [ -V | --version ] [ --help ]
857 @var{infile} [@var{outfile}]
860 The @sc{gnu} @code{objcopy} utility copies the contents of an object
861 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
862 read and write the object files. It can write the destination object
863 file in a format different from that of the source object file. The
864 exact behavior of @code{objcopy} is controlled by command-line options.
866 @code{objcopy} creates temporary files to do its translations and
867 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
868 translation work; it has access to all the formats described in @sc{bfd}
869 and thus is able to recognize most formats without being told
870 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
872 @code{objcopy} can be used to generate S-records by using an output
873 target of @samp{srec} (e.g., use @samp{-O srec}).
875 @code{objcopy} can be used to generate a raw binary file by using an
876 output target of @samp{binary} (e.g., use @samp{-O binary}). When
877 @code{objcopy} generates a raw binary file, it will essentially produce
878 a memory dump of the contents of the input object file. All symbols and
879 relocation information will be discarded. The memory dump will start at
880 the load address of the lowest section copied into the output file.
882 When generating an S-record or a raw binary file, it may be helpful to
883 use @samp{-S} to remove sections containing debugging information. In
884 some cases @samp{-R} will be useful to remove sections which contain
885 information which is not needed by the binary file.
890 The source and output files, respectively.
891 If you do not specify @var{outfile}, @code{objcopy} creates a
892 temporary file and destructively renames the result with
893 the name of @var{infile}.
895 @item -I @var{bfdname}
896 @itemx --input-target=@var{bfdname}
897 Consider the source file's object format to be @var{bfdname}, rather than
898 attempting to deduce it. @xref{Target Selection}, for more information.
900 @item -O @var{bfdname}
901 @itemx --output-target=@var{bfdname}
902 Write the output file using the object format @var{bfdname}.
903 @xref{Target Selection}, for more information.
905 @item -F @var{bfdname}
906 @itemx --target=@var{bfdname}
907 Use @var{bfdname} as the object format for both the input and the output
908 file; i.e., simply transfer data from source to destination with no
909 translation. @xref{Target Selection}, for more information.
911 @item -j @var{sectionname}
912 @itemx --only-section=@var{sectionname}
913 Copy only the named section from the input file to the output file.
914 This option may be given more than once. Note that using this option
915 inappropriately may make the output file unusable.
917 @item -R @var{sectionname}
918 @itemx --remove-section=@var{sectionname}
919 Remove any section named @var{sectionname} from the output file. This
920 option may be given more than once. Note that using this option
921 inappropriately may make the output file unusable.
925 Do not copy relocation and symbol information from the source file.
929 Do not copy debugging symbols from the source file.
931 @item --strip-unneeded
932 Strip all symbols that are not needed for relocation processing.
934 @item -K @var{symbolname}
935 @itemx --keep-symbol=@var{symbolname}
936 Copy only symbol @var{symbolname} from the source file. This option may
937 be given more than once.
939 @item -N @var{symbolname}
940 @itemx --strip-symbol=@var{symbolname}
941 Do not copy symbol @var{symbolname} from the source file. This option
942 may be given more than once.
944 @item -L @var{symbolname}
945 @itemx --localize-symbol=@var{symbolname}
946 Make symbol @var{symbolname} local to the file, so that it is not
947 visible externally. This option may be given more than once.
949 @item -W @var{symbolname}
950 @itemx --weaken-symbol=@var{symbolname}
951 Make symbol @var{symbolname} weak. This option may be given more than once.
955 Do not copy non-global symbols from the source file.
956 @c FIXME any reason to prefer "non-global" to "local" here?
959 @itemx --discard-locals
960 Do not copy compiler-generated local symbols.
961 (These usually start with @samp{L} or @samp{.}.)
964 @itemx --byte=@var{byte}
965 Keep only every @var{byte}th byte of the input file (header data is not
966 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
967 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
968 option, or the default of 4. This option is useful for creating files
969 to program @sc{rom}. It is typically used with an @code{srec} output
972 @item -i @var{interleave}
973 @itemx --interleave=@var{interleave}
974 Only copy one out of every @var{interleave} bytes. Select which byte to
975 copy with the @var{-b} or @samp{--byte} option. The default is 4.
976 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
980 @itemx --preserve-dates
981 Set the access and modification dates of the output file to be the same
982 as those of the input file.
985 Convert debugging information, if possible. This is not the default
986 because only certain debugging formats are supported, and the
987 conversion process can be time consuming.
989 @item --gap-fill @var{val}
990 Fill gaps between sections with @var{val}. This operation applies to
991 the @emph{load address} (LMA) of the sections. It is done by increasing
992 the size of the section with the lower address, and filling in the extra
993 space created with @var{val}.
995 @item --pad-to @var{address}
996 Pad the output file up to the load address @var{address}. This is
997 done by increasing the size of the last section. The extra space is
998 filled in with the value specified by @samp{--gap-fill} (default zero).
1000 @item --set-start @var{val}
1001 Set the address of the new file to @var{val}. Not all object file
1002 formats support setting the start address.
1004 @item --change-start @var{incr}
1005 @itemx --adjust-start @var{incr}
1006 @cindex changing start address
1007 Change the start address by adding @var{incr}. Not all object file
1008 formats support setting the start address.
1010 @item --change-addresses @var{incr}
1011 @itemx --adjust-vma @var{incr}
1012 @cindex changing object addresses
1013 Change the VMA and LMA addresses of all sections, as well as the start
1014 address, by adding @var{incr}. Some object file formats do not permit
1015 section addresses to be changed arbitrarily. Note that this does not
1016 relocate the sections; if the program expects sections to be loaded at a
1017 certain address, and this option is used to change the sections such
1018 that they are loaded at a different address, the program may fail.
1020 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1021 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1022 @cindex changing section address
1023 Set or change both the VMA address and the LMA address of the named
1024 @var{section}. If @samp{=} is used, the section address is set to
1025 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1026 section address. See the comments under @samp{--change-addresses},
1027 above. If @var{section} does not exist in the input file, a warning will
1028 be issued, unless @samp{--no-change-warnings} is used.
1030 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1031 @cindex changing section LMA
1032 Set or change the LMA address of the named @var{section}. The LMA
1033 address is the address where the section will be loaded into memory at
1034 program load time. Normally this is the same as the VMA address, which
1035 is the address of the section at program run time, but on some systems,
1036 especially those where a program is held in ROM, the two can be
1037 different. If @samp{=} is used, the section address is set to
1038 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1039 section address. See the comments under @samp{--change-addresses},
1040 above. If @var{section} does not exist in the input file, a warning
1041 will be issued, unless @samp{--no-change-warnings} is used.
1043 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1044 @cindex changing section VMA
1045 Set or change the VMA address of the named @var{section}. The VMA
1046 address is the address where the section will be located once the
1047 program has started executing. Normally this is the same as the LMA
1048 address, which is the address where the section will be loaded into
1049 memory, but on some systems, especially those where a program is held in
1050 ROM, the two can be different. If @samp{=} is used, the section address
1051 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1052 from the section address. See the comments under
1053 @samp{--change-addresses}, above. If @var{section} does not exist in
1054 the input file, a warning will be issued, unless
1055 @samp{--no-change-warnings} is used.
1057 @item --change-warnings
1058 @itemx --adjust-warnings
1059 If @samp{--change-section-address} or @samp{--change-section-lma} or
1060 @samp{--change-section-vma} is used, and the named section does not
1061 exist, issue a warning. This is the default.
1063 @item --no-change-warnings
1064 @itemx --no-adjust-warnings
1065 Do not issue a warning if @samp{--change-section-address} or
1066 @samp{--adjust-section-lma} or @samp{--adjust-section-vma} is used, even
1067 if the named section does not exist.
1069 @item --set-section-flags @var{section}=@var{flags}
1070 Set the flags for the named section. The @var{flags} argument is a
1071 comma separated string of flag names. The recognized names are
1072 @samp{alloc}, @samp{contents}, @samp{load}, @samp{readonly},
1073 @samp{code}, @samp{data}, and @samp{rom}. You can set the
1074 @samp{contents} flag for a section which does not have contents, but it
1075 is not meaningful to clear the @samp{contents} flag of a section which
1076 does have contents--just remove the section instead. Not all flags are
1077 meaningful for all object file formats.
1079 @item --add-section @var{sectionname}=@var{filename}
1080 Add a new section named @var{sectionname} while copying the file. The
1081 contents of the new section are taken from the file @var{filename}. The
1082 size of the section will be the size of the file. This option only
1083 works on file formats which can support sections with arbitrary names.
1085 @item --change-leading-char
1086 Some object file formats use special characters at the start of
1087 symbols. The most common such character is underscore, which compilers
1088 often add before every symbol. This option tells @code{objcopy} to
1089 change the leading character of every symbol when it converts between
1090 object file formats. If the object file formats use the same leading
1091 character, this option has no effect. Otherwise, it will add a
1092 character, or remove a character, or change a character, as
1095 @item --remove-leading-char
1096 If the first character of a global symbol is a special symbol leading
1097 character used by the object file format, remove the character. The
1098 most common symbol leading character is underscore. This option will
1099 remove a leading underscore from all global symbols. This can be useful
1100 if you want to link together objects of different file formats with
1101 different conventions for symbol names. This is different from
1102 @code{--change-leading-char} because it always changes the symbol name
1103 when appropriate, regardless of the object file format of the output
1107 Change all global symbols in the file to be weak. This can be useful
1108 when building an object which will be linked against other objects using
1109 the @code{-R} option to the linker. This option is only effective when
1110 using an object file format which supports weak symbols.
1114 Show the version number of @code{objcopy}.
1118 Verbose output: list all object files modified. In the case of
1119 archives, @samp{objcopy -V} lists all members of the archive.
1122 Show a summary of the options to @code{objcopy}.
1128 @cindex object file information
1132 objdump [ -a | --archive-headers ]
1133 [ -b @var{bfdname} | --target=@var{bfdname} ] [ --debugging ]
1134 [ -C | --demangle ] [ -d | --disassemble ]
1135 [ -D | --disassemble-all ] [ --disassemble-zeroes ]
1136 [ -EB | -EL | --endian=@{big | little @} ]
1137 [ -f | --file-headers ]
1138 [ -h | --section-headers | --headers ] [ -i | --info ]
1139 [ -j @var{section} | --section=@var{section} ]
1140 [ -l | --line-numbers ] [ -S | --source ]
1141 [ -m @var{machine} | --architecture=@var{machine} ]
1142 [ -M @var{options} | --disassembler-options=@var{options}]
1143 [ -p | --private-headers ]
1144 [ -r | --reloc ] [ -R | --dynamic-reloc ]
1145 [ -s | --full-contents ] [ --stabs ]
1146 [ -t | --syms ] [ -T | --dynamic-syms ] [ -x | --all-headers ]
1147 [ -w | --wide ] [ --start-address=@var{address} ]
1148 [ --stop-address=@var{address} ]
1149 [ --prefix-addresses] [ --[no-]show-raw-insn ]
1150 [ --adjust-vma=@var{offset} ]
1151 [ --version ] [ --help ]
1152 @var{objfile}@dots{}
1155 @code{objdump} displays information about one or more object files.
1156 The options control what particular information to display. This
1157 information is mostly useful to programmers who are working on the
1158 compilation tools, as opposed to programmers who just want their
1159 program to compile and work.
1161 @var{objfile}@dots{} are the object files to be examined. When you
1162 specify archives, @code{objdump} shows information on each of the member
1165 The long and short forms of options, shown here as alternatives, are
1166 equivalent. At least one option besides @samp{-l} must be given.
1170 @itemx --archive-header
1171 @cindex archive headers
1172 If any of the @var{objfile} files are archives, display the archive
1173 header information (in a format similar to @samp{ls -l}). Besides the
1174 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1175 the object file format of each archive member.
1177 @item --adjust-vma=@var{offset}
1178 @cindex section addresses in objdump
1179 @cindex VMA in objdump
1180 When dumping information, first add @var{offset} to all the section
1181 addresses. This is useful if the section addresses do not correspond to
1182 the symbol table, which can happen when putting sections at particular
1183 addresses when using a format which can not represent section addresses,
1186 @item -b @var{bfdname}
1187 @itemx --target=@var{bfdname}
1188 @cindex object code format
1189 Specify that the object-code format for the object files is
1190 @var{bfdname}. This option may not be necessary; @var{objdump} can
1191 automatically recognize many formats.
1195 objdump -b oasys -m vax -h fu.o
1198 displays summary information from the section headers (@samp{-h}) of
1199 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1200 file in the format produced by Oasys compilers. You can list the
1201 formats available with the @samp{-i} option.
1202 @xref{Target Selection}, for more information.
1206 @cindex demangling in objdump
1207 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1208 Besides removing any initial underscore prepended by the system, this
1209 makes C++ function names readable. @xref{c++filt}, for more information
1213 Display debugging information. This attempts to parse debugging
1214 information stored in the file and print it out using a C like syntax.
1215 Only certain types of debugging information have been implemented.
1218 @itemx --disassemble
1219 @cindex disassembling object code
1220 @cindex machine instructions
1221 Display the assembler mnemonics for the machine instructions from
1222 @var{objfile}. This option only disassembles those sections which are
1223 expected to contain instructions.
1226 @itemx --disassemble-all
1227 Like @samp{-d}, but disassemble the contents of all sections, not just
1228 those expected to contain instructions.
1230 @item --prefix-addresses
1231 When disassembling, print the complete address on each line. This is
1232 the older disassembly format.
1234 @item --disassemble-zeroes
1235 Normally the disassembly output will skip blocks of zeroes. This
1236 option directs the disassembler to disassemble those blocks, just like
1241 @itemx --endian=@{big|little@}
1243 @cindex disassembly endianness
1244 Specify the endianness of the object files. This only affects
1245 disassembly. This can be useful when disassembling a file format which
1246 does not describe endianness information, such as S-records.
1249 @itemx --file-header
1250 @cindex object file header
1251 Display summary information from the overall header of
1252 each of the @var{objfile} files.
1255 @itemx --section-header
1257 @cindex section headers
1258 Display summary information from the section headers of the
1261 File segments may be relocated to nonstandard addresses, for example by
1262 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1263 @code{ld}. However, some object file formats, such as a.out, do not
1264 store the starting address of the file segments. In those situations,
1265 although @code{ld} relocates the sections correctly, using @samp{objdump
1266 -h} to list the file section headers cannot show the correct addresses.
1267 Instead, it shows the usual addresses, which are implicit for the
1271 Print a summary of the options to @code{objdump} and exit.
1275 @cindex architectures available
1276 @cindex object formats available
1277 Display a list showing all architectures and object formats available
1278 for specification with @samp{-b} or @samp{-m}.
1281 @itemx --section=@var{name}
1282 @cindex section information
1283 Display information only for section @var{name}.
1286 @itemx --line-numbers
1287 @cindex source filenames for object files
1288 Label the display (using debugging information) with the filename and
1289 source line numbers corresponding to the object code or relocs shown.
1290 Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1292 @item -m @var{machine}
1293 @itemx --architecture=@var{machine}
1294 @cindex architecture
1295 @cindex disassembly architecture
1296 Specify the architecture to use when disassembling object files. This
1297 can be useful when disassembling object files which do not describe
1298 architecture information, such as S-records. You can list the available
1299 architectures with the @samp{-i} option.
1301 @item -M @var{options}
1302 @itemx --disassembler-options=@var{options}
1303 Pass target specific information to the disassembler. Only supported on
1306 If the target is an ARM architecture then this switch can be used to
1307 select which register name set is used during disassembler. Specifying
1308 @samp{--disassembler-options=reg-name-std} (the default) will select the
1309 register names as used in ARM's instruction set documentation, but with
1310 register 13 called 'sp', register 14 called 'lr' and register 15 called
1311 'pc'. Specifying @samp{--disassembler-options=reg-names-apcs} will
1312 select the name set used by the ARM Procedure Call Standard, whilst
1313 specifying @samp{--disassembler-options=reg-names-raw} will just use
1314 @samp{r} followed by the register number.
1317 @itemx --private-headers
1318 Print information that is specific to the object file format. The exact
1319 information printed depends upon the object file format. For some
1320 object file formats, no additional information is printed.
1324 @cindex relocation entries, in object file
1325 Print the relocation entries of the file. If used with @samp{-d} or
1326 @samp{-D}, the relocations are printed interspersed with the
1330 @itemx --dynamic-reloc
1331 @cindex dynamic relocation entries, in object file
1332 Print the dynamic relocation entries of the file. This is only
1333 meaningful for dynamic objects, such as certain types of shared
1337 @itemx --full-contents
1338 @cindex sections, full contents
1339 @cindex object file sections
1340 Display the full contents of any sections requested.
1344 @cindex source disassembly
1345 @cindex disassembly, with source
1346 Display source code intermixed with disassembly, if possible. Implies
1349 @item --show-raw-insn
1350 When disassembling instructions, print the instruction in hex as well as
1351 in symbolic form. This is the default except when
1352 @code{--prefix-addresses} is used.
1354 @item --no-show-raw-insn
1355 When disassembling instructions, do not print the instruction bytes.
1356 This is the default when @code{--prefix-addresses} is used.
1361 @cindex debug symbols
1362 @cindex ELF object file format
1363 Display the full contents of any sections requested. Display the
1364 contents of the .stab and .stab.index and .stab.excl sections from an
1365 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1366 @code{.stab} debugging symbol-table entries are carried in an ELF
1367 section. In most other file formats, debugging symbol-table entries are
1368 interleaved with linkage symbols, and are visible in the @samp{--syms}
1369 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1370 Overview,stabs.info, The ``stabs'' debug format}.
1372 @item --start-address=@var{address}
1373 @cindex start-address
1374 Start displaying data at the specified address. This affects the output
1375 of the @code{-d}, @code{-r} and @code{-s} options.
1377 @item --stop-address=@var{address}
1378 @cindex stop-address
1379 Stop displaying data at the specified address. This affects the output
1380 of the @code{-d}, @code{-r} and @code{-s} options.
1384 @cindex symbol table entries, printing
1385 Print the symbol table entries of the file.
1386 This is similar to the information provided by the @samp{nm} program.
1389 @itemx --dynamic-syms
1390 @cindex dynamic symbol table entries, printing
1391 Print the dynamic symbol table entries of the file. This is only
1392 meaningful for dynamic objects, such as certain types of shared
1393 libraries. This is similar to the information provided by the @samp{nm}
1394 program when given the @samp{-D} (@samp{--dynamic}) option.
1397 Print the version number of @code{objdump} and exit.
1401 @cindex all header information, object file
1402 @cindex header information, all
1403 Display all available header information, including the symbol table and
1404 relocation entries. Using @samp{-x} is equivalent to specifying all of
1405 @samp{-a -f -h -r -t}.
1409 @cindex wide output, printing
1410 Format some lines for output devices that have more than 80 columns.
1417 @cindex archive contents
1418 @cindex symbol index
1421 ranlib [-vV] @var{archive}
1424 @code{ranlib} generates an index to the contents of an archive and
1425 stores it in the archive. The index lists each symbol defined by a
1426 member of an archive that is a relocatable object file.
1428 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1430 An archive with such an index speeds up linking to the library and
1431 allows routines in the library to call each other without regard to
1432 their placement in the archive.
1434 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1435 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1441 Show the version number of @code{ranlib}.
1448 @cindex section sizes
1451 size [ -A | -B | --format=@var{compatibility} ]
1452 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1453 [ --target=@var{bfdname} ] [ -V | --version ]
1454 [ @var{objfile}@dots{} ]
1457 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1458 size---for each of the object or archive files @var{objfile} in its
1459 argument list. By default, one line of output is generated for each
1460 object file or each module in an archive.
1462 @var{objfile}@dots{} are the object files to be examined.
1463 If none are specified, the file @code{a.out} will be used.
1465 The command line options have the following meanings:
1470 @itemx --format=@var{compatibility}
1471 @cindex @code{size} display format
1472 Using one of these options, you can choose whether the output from @sc{gnu}
1473 @code{size} resembles output from System V @code{size} (using @samp{-A},
1474 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1475 @samp{--format=berkeley}). The default is the one-line format similar to
1477 @c Bonus for doc-source readers: you can also say --format=strange (or
1478 @c anything else that starts with 's') for sysv, and --format=boring (or
1479 @c anything else that starts with 'b') for Berkeley.
1481 Here is an example of the Berkeley (default) format of output from
1484 size --format=Berkeley ranlib size
1485 text data bss dec hex filename
1486 294880 81920 11592 388392 5ed28 ranlib
1487 294880 81920 11888 388688 5ee50 size
1491 This is the same data, but displayed closer to System V conventions:
1494 size --format=SysV ranlib size
1512 Show a summary of acceptable arguments and options.
1517 @itemx --radix=@var{number}
1518 @cindex @code{size} number format
1519 @cindex radix for section sizes
1520 Using one of these options, you can control whether the size of each
1521 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1522 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1523 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1524 values (8, 10, 16) are supported. The total size is always given in two
1525 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1526 octal and hexadecimal if you're using @samp{-o}.
1528 @item --target=@var{bfdname}
1529 @cindex object code format
1530 Specify that the object-code format for @var{objfile} is
1531 @var{bfdname}. This option may not be necessary; @code{size} can
1532 automatically recognize many formats.
1533 @xref{Target Selection}, for more information.
1537 Display the version number of @code{size}.
1543 @cindex listings strings
1544 @cindex printing strings
1545 @cindex strings, printing
1548 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1549 [--all] [--print-file-name] [--bytes=@var{min-len}]
1550 [--radix=@var{radix}] [--target=@var{bfdname}]
1551 [--help] [--version] @var{file}@dots{}
1554 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1555 character sequences that are at least 4 characters long (or the number
1556 given with the options below) and are followed by an unprintable
1557 character. By default, it only prints the strings from the initialized
1558 and loaded sections of object files; for other types of files, it prints
1559 the strings from the whole file.
1561 @code{strings} is mainly useful for determining the contents of non-text
1568 Do not scan only the initialized and loaded sections of object files;
1569 scan the whole files.
1572 @itemx --print-file-name
1573 Print the name of the file before each string.
1576 Print a summary of the program usage on the standard output and exit.
1578 @item -@var{min-len}
1579 @itemx -n @var{min-len}
1580 @itemx --bytes=@var{min-len}
1581 Print sequences of characters that are at least @var{min-len} characters
1582 long, instead of the default 4.
1585 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1586 act like @samp{-t d} instead. Since we can not be compatible with both
1587 ways, we simply chose one.
1589 @item -t @var{radix}
1590 @itemx --radix=@var{radix}
1591 Print the offset within the file before each string. The single
1592 character argument specifies the radix of the offset---@samp{o} for
1593 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1595 @item --target=@var{bfdname}
1596 @cindex object code format
1597 Specify an object code format other than your system's default format.
1598 @xref{Target Selection}, for more information.
1602 Print the program version number on the standard output and exit.
1609 @cindex removing symbols
1610 @cindex discarding symbols
1611 @cindex symbols, discarding
1614 strip [ -F @var{bfdname} | --target=@var{bfdname} ]
1615 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1616 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1617 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1618 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1619 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1620 [ -x | --discard-all ] [ -X | --discard-locals ]
1621 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1622 [ -o @var{file} ] [ -p | --preserve-dates ]
1623 [ -v | --verbose ] [ -V | --version ] [ --help ]
1624 @var{objfile}@dots{}
1627 @sc{gnu} @code{strip} discards all symbols from object files
1628 @var{objfile}. The list of object files may include archives.
1629 At least one object file must be given.
1631 @code{strip} modifies the files named in its argument,
1632 rather than writing modified copies under different names.
1635 @item -F @var{bfdname}
1636 @itemx --target=@var{bfdname}
1637 Treat the original @var{objfile} as a file with the object
1638 code format @var{bfdname}, and rewrite it in the same format.
1639 @xref{Target Selection}, for more information.
1642 Show a summary of the options to @code{strip} and exit.
1644 @item -I @var{bfdname}
1645 @itemx --input-target=@var{bfdname}
1646 Treat the original @var{objfile} as a file with the object
1647 code format @var{bfdname}.
1648 @xref{Target Selection}, for more information.
1650 @item -O @var{bfdname}
1651 @itemx --output-target=@var{bfdname}
1652 Replace @var{objfile} with a file in the output format @var{bfdname}.
1653 @xref{Target Selection}, for more information.
1655 @item -R @var{sectionname}
1656 @itemx --remove-section=@var{sectionname}
1657 Remove any section named @var{sectionname} from the output file. This
1658 option may be given more than once. Note that using this option
1659 inappropriately may make the output file unusable.
1667 @itemx --strip-debug
1668 Remove debugging symbols only.
1670 @item --strip-unneeded
1671 Remove all symbols that are not needed for relocation processing.
1673 @item -K @var{symbolname}
1674 @itemx --keep-symbol=@var{symbolname}
1675 Keep only symbol @var{symbolname} from the source file. This option may
1676 be given more than once.
1678 @item -N @var{symbolname}
1679 @itemx --strip-symbol=@var{symbolname}
1680 Remove symbol @var{symbolname} from the source file. This option may be
1681 given more than once, and may be combined with strip options other than
1685 Put the stripped output in @var{file}, rather than replacing the
1686 existing file. When this argument is used, only one @var{objfile}
1687 argument may be specified.
1690 @itemx --preserve-dates
1691 Preserve the access and modification dates of the file.
1694 @itemx --discard-all
1695 Remove non-global symbols.
1698 @itemx --discard-locals
1699 Remove compiler-generated local symbols.
1700 (These usually start with @samp{L} or @samp{.}.)
1704 Show the version number for @code{strip}.
1708 Verbose output: list all object files modified. In the case of
1709 archives, @samp{strip -v} lists all members of the archive.
1712 @node c++filt, addr2line, strip, Top
1716 @cindex demangling C++ symbols
1719 c++filt [ -_ | --strip-underscores ]
1721 [ -n | --no-strip-underscores ]
1722 [ -s @var{format} | --format=@var{format} ]
1723 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1727 The C++ and Java languages provides function overloading, which means
1728 that you can write many functions with the same name (providing each
1729 takes parameters of different types). All C++ and Java function names
1730 are encoded into a low-level assembly label (this process is known as
1731 @dfn{mangling}). The @code{c++filt}
1732 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
1733 MS-DOS this program is named @code{cxxfilt}.}
1734 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
1735 names into user-level names so that the linker can keep these overloaded
1736 functions from clashing.
1738 Every alphanumeric word (consisting of letters, digits, underscores,
1739 dollars, or periods) seen in the input is a potential label. If the
1740 label decodes into a C++ name, the C++ name replaces the low-level
1743 You can use @code{c++filt} to decipher individual symbols:
1746 c++filt @var{symbol}
1749 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1750 names from the standard input and writes the demangled names to the
1751 standard output. All results are printed on the standard output.
1755 @itemx --strip-underscores
1756 On some systems, both the C and C++ compilers put an underscore in front
1757 of every name. For example, the C name @code{foo} gets the low-level
1758 name @code{_foo}. This option removes the initial underscore. Whether
1759 @code{c++filt} removes the underscore by default is target dependent.
1763 Prints demangled names using Java syntax. The default is to use C++
1767 @itemx --no-strip-underscores
1768 Do not remove the initial underscore.
1770 @item -s @var{format}
1771 @itemx --format=@var{format}
1772 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1773 different C++ compilers. The argument to this option selects which
1778 the one used by the @sc{gnu} compiler (the default method)
1780 the one used by the Lucid compiler
1782 the one specified by the C++ Annotated Reference Manual
1784 the one used by the HP compiler
1786 the one used by the EDG compiler
1790 Print a summary of the options to @code{c++filt} and exit.
1793 Print the version number of @code{c++filt} and exit.
1797 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1798 user interface are subject to change in future releases. In particular,
1799 a command-line option may be required in the the future to decode a name
1800 passed as an argument on the command line; in other words,
1803 c++filt @var{symbol}
1807 may in a future release become
1810 c++filt @var{option} @var{symbol}
1818 @cindex address to file name and line number
1821 addr2line [ -b @var{bfdname} | --target=@var{bfdname} ]
1823 [ -e @var{filename} | --exe=@var{filename} ]
1824 [ -f | --functions ] [ -s | --basename ]
1825 [ -H | --help ] [ -V | --version ]
1829 @code{addr2line} translates program addresses into file names and line
1830 numbers. Given an address and an executable, it uses the debugging
1831 information in the executable to figure out which file name and line
1832 number are associated with a given address.
1834 The executable to use is specified with the @code{-e} option. The
1835 default is @file{a.out}.
1837 @code{addr2line} has two modes of operation.
1839 In the first, hexadecimal addresses are specified on the command line,
1840 and @code{addr2line} displays the file name and line number for each
1843 In the second, @code{addr2line} reads hexadecimal addresses from
1844 standard input, and prints the file name and line number for each
1845 address on standard output. In this mode, @code{addr2line} may be used
1846 in a pipe to convert dynamically chosen addresses.
1848 The format of the output is @samp{FILENAME:LINENO}. The file name and
1849 line number for each address is printed on a separate line. If the
1850 @code{-f} option is used, then each @samp{FILENAME:LINENO} line is
1851 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
1852 containing the address.
1854 If the file name or function name can not be determined,
1855 @code{addr2line} will print two question marks in their place. If the
1856 line number can not be determined, @code{addr2line} will print 0.
1858 The long and short forms of options, shown here as alternatives, are
1862 @item -b @var{bfdname}
1863 @itemx --target=@var{bfdname}
1864 @cindex object code format
1865 Specify that the object-code format for the object files is
1870 @cindex demangling in objdump
1871 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1872 Besides removing any initial underscore prepended by the system, this
1873 makes C++ function names readable. @xref{c++filt}, for more information
1876 @item -e @var{filename}
1877 @itemx --exe=@var{filename}
1878 Specify the name of the executable for which addresses should be
1879 translated. The default file is @file{a.out}.
1883 Display function names as well as file and line number information.
1887 Display only the base of each file name.
1893 @code{nlmconv} converts a relocatable object file into a NetWare
1897 @code{nlmconv} currently works with @samp{i386} object
1898 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1899 object files in @sc{elf}, or @code{a.out} format@footnote{
1900 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1901 format in the Binary File Descriptor library. It has only been tested
1902 with the above formats.}.
1906 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1907 utilities, since it is only useful for NLM targets.
1911 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1912 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1913 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1914 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1915 [ -h | --help ] [ -V | --version ]
1916 @var{infile} @var{outfile}
1919 @code{nlmconv} converts the relocatable @samp{i386} object file
1920 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1921 reading @var{headerfile} for NLM header information. For instructions
1922 on writing the NLM command file language used in header files, see the
1923 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1924 Development and Tools Overview}, which is part of the NLM Software
1925 Developer's Kit (``NLM SDK''), available from Novell, Inc.
1926 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
1927 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
1930 @code{nlmconv} can perform a link step. In other words, you can list
1931 more than one object file for input if you list them in the definitions
1932 file (rather than simply specifying one input file on the command line).
1933 In this case, @code{nlmconv} calls the linker for you.
1936 @item -I @var{bfdname}
1937 @itemx --input-target=@var{bfdname}
1938 Object format of the input file. @code{nlmconv} can usually determine
1939 the format of a given file (so no default is necessary).
1940 @xref{Target Selection}, for more information.
1942 @item -O @var{bfdname}
1943 @itemx --output-target=@var{bfdname}
1944 Object format of the output file. @code{nlmconv} infers the output
1945 format based on the input format, e.g. for a @samp{i386} input file the
1946 output format is @samp{nlm32-i386}.
1947 @xref{Target Selection}, for more information.
1949 @item -T @var{headerfile}
1950 @itemx --header-file=@var{headerfile}
1951 Reads @var{headerfile} for NLM header information. For instructions on
1952 writing the NLM command file language used in header files, see@ see the
1953 @samp{linkers} section, of the @cite{NLM Development and Tools
1954 Overview}, which is part of the NLM Software Developer's Kit, available
1959 Displays (on standard error) the linker command line used by @code{nlmconv}.
1961 @item -l @var{linker}
1962 @itemx --linker=@var{linker}
1963 Use @var{linker} for any linking. @var{linker} can be an absolute or a
1968 Prints a usage summary.
1972 Prints the version number for @code{nlmconv}.
1978 @code{windres} may be used to manipulate Windows resources.
1981 @emph{Warning:} @code{windres} is not always built as part of the binary
1982 utilities, since it is only useful for Windows targets.
1986 windres [options] [input-file] [output-file]
1989 @code{windres} reads resources from an input file and copies them into
1990 an output file. Either file may be in one of three formats:
1994 A text format read by the Resource Compiler.
1997 A binary format generated by the Resource Compiler.
2000 A COFF object or executable.
2003 The exact description of these different formats is available in
2004 documentation from Microsoft.
2006 When @code{windres} converts from the @code{rc} format to the @code{res}
2007 format, it is acting like the Windows Resource Compiler. When
2008 @code{windres} converts from the @code{res} format to the @code{coff}
2009 format, it is acting like the Windows @code{CVTRES} program.
2011 When @code{windres} generates an @code{rc} file, the output is similar
2012 but not identical to the format expected for the input. When an input
2013 @code{rc} file refers to an external filename, an output @code{rc} file
2014 will instead include the file contents.
2016 If the input or output format is not specified, @code{windres} will
2017 guess based on the file name, or, for the input file, the file contents.
2018 A file with an extension of @file{.rc} will be treated as an @code{rc}
2019 file, a file with an extension of @file{.res} will be treated as a
2020 @code{res} file, and a file with an extension of @file{.o} or
2021 @file{.exe} will be treated as a @code{coff} file.
2023 If no output file is specified, @code{windres} will print the resources
2024 in @code{rc} format to standard output.
2026 The normal use is for you to write an @code{rc} file, use @code{windres}
2027 to convert it to a COFF object file, and then link the COFF file into
2028 your application. This will make the resources described in the
2029 @code{rc} file available to Windows.
2032 @item -i @var{filename}
2033 @itemx --input @var{filename}
2034 The name of the input file. If this option is not used, then
2035 @code{windres} will use the first non-option argument as the input file
2036 name. If there are no non-option arguments, then @code{windres} will
2037 read from standard input. @code{windres} can not read a COFF file from
2040 @item -o @var{filename}
2041 @itemx --output @var{filename}
2042 The name of the output file. If this option is not used, then
2043 @code{windres} will use the first non-option argument, after any used
2044 for the input file name, as the output file name. If there is no
2045 non-option argument, then @code{windres} will write to standard output.
2046 @code{windres} can not write a COFF file to standard output.
2048 @item -I @var{format}
2049 @itemx --input-format @var{format}
2050 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2051 @samp{coff}. If no input format is specified, @code{windres} will
2052 guess, as described above.
2054 @item -O @var{format}
2055 @itemx --output-format @var{format}
2056 The output format to generate. @var{format} may be @samp{res},
2057 @samp{rc}, or @samp{coff}. If no output format is specified,
2058 @code{windres} will guess, as described above.
2060 @item -F @var{target}
2061 @itemx --target @var{target}
2062 Specify the BFD format to use for a COFF file as input or output. This
2063 is a BFD target name; you can use the @code{--help} option to see a list
2064 of supported targets. Normally @code{windres} will use the default
2065 format, which is the first one listed by the @code{--help} option.
2066 @ref{Target Selection}.
2068 @item --preprocessor @var{program}
2069 When @code{windres} reads an @code{rc} file, it runs it through the C
2070 preprocessor first. This option may be used to specify the preprocessor
2071 to use, including any leading arguments. The default preprocessor
2072 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2074 @item --include-dir @var{directory}
2075 Specify an include directory to use when reading an @code{rc} file.
2076 @code{windres} will pass this to the preprocessor as an @code{-I}
2077 option. @code{windres} will also search this directory when looking for
2078 files named in the @code{rc} file.
2080 @item -D @var{target}
2081 @itemx --define @var{sym[=val]}
2082 Specify a @code{-D} option to pass to the preprocessor when reading an
2086 Enable verbose mode. This tells you what the preprocessor is if you
2089 @item --language @var{val}
2090 Specify the default language to use when reading an @code{rc} file.
2091 @var{val} should be a hexadecimal language code. The low eight bits are
2092 the language, and the high eight bits are the sublanguage.
2095 Prints a usage summary.
2098 Prints the version number for @code{windres}.
2101 If @code{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2102 this will turn on parser debugging.
2107 @chapter Create files needed to build and use DLLs
2111 @code{dlltool} may be used to create the files needed to build and use
2112 dynamic link libraries (DLLs).
2115 @emph{Warning:} @code{dlltool} is not always built as part of the binary
2116 utilities, since it is only useful for those targets which support DLLs.
2120 dlltool [-d|--input-def @var{def-file-name}]
2121 [-b|--base-file @var{base-file-name}]
2122 [-e|--output-exp @var{exports-file-name}]
2123 [-z|--output-def @var{def-file-name}]
2124 [-l|--output-lib @var{library-file-name}]
2125 [--export-all-symbols] [--no-export-all-symbols]
2126 [--exclude-symbols @var{list}]
2127 [--no-default-excludes]
2128 [-S|--as @var{path-to-assembler}] [-f|--as-flags @var{options}]
2129 [-D|--dllname @var{name}] [-m|--machine @var{machine}]
2130 [-a|--add-indirect] [-U|--add-underscore] [-k|--kill-at]
2131 [-A|--add-stdcall-alias]
2132 [-x|--no-idata4] [-c|--no-idata5] [-i|--interwork]
2133 [-n|--nodelete] [-v|--verbose] [-h|--help] [-V|--version]
2134 [object-file @dots{}]
2137 @code{dlltool} reads its inputs, which can come from the @samp{-d} and
2138 @samp{-b} options as well as object files specified on the command
2139 line. It then processes these inputs and if the @samp{-e} option has
2140 been specified it creates a exports file. If the @samp{-l} option
2141 has been specified it creates a library file and if the @samp{-z} option
2142 has been specified it creates a def file. Any or all of the -e, -l
2143 and -z options can be present in one invocation of dlltool.
2145 When creating a DLL, along with the source for the DLL, it is necessary
2146 to have three other files. @code{dlltool} can help with the creation of
2149 The first file is a @samp{.def} file which specifies which functions are
2150 exported from the DLL, which functions the DLL imports, and so on. This
2151 is a text file and can be created by hand, or @code{dlltool} can be used
2152 to create it using the @samp{-z} option. In this case @code{dlltool}
2153 will scan the object files specified on its command line looking for
2154 those functions which have been specially marked as being exported and
2155 put entries for them in the .def file it creates.
2157 In order to mark a function as being exported from a DLL, it needs to
2158 have an @samp{-export:<name_of_function>} entry in the @samp{.drectve}
2159 section of the object file. This can be done in C by using the
2163 asm (".section .drectve");
2164 asm (".ascii \"-export:my_func\"");
2166 int my_func (void) @{ @dots{} @}
2169 The second file needed for DLL creation is an exports file. This file
2170 is linked with the object files that make up the body of the DLL and it
2171 handles the interface between the DLL and the outside world. This is a
2172 binary file and it can be created by giving the @samp{-e} option to
2173 @code{dlltool} when it is creating or reading in a .def file.
2175 The third file needed for DLL creation is the library file that programs
2176 will link with in order to access the functions in the DLL. This file
2177 can be created by giving the @samp{-l} option to dlltool when it
2178 is creating or reading in a .def file.
2180 @code{dlltool} builds the library file by hand, but it builds the
2181 exports file by creating temporary files containing assembler statements
2182 and then assembling these. The @samp{-S} command line option can be
2183 used to specify the path to the assembler that dlltool will use,
2184 and the @samp{-f} option can be used to pass specific flags to that
2185 assembler. The @samp{-n} can be used to prevent dlltool from deleting
2186 these temporary assembler files when it is done, and if @samp{-n} is
2187 specified twice then this will prevent dlltool from deleting the
2188 temporary object files it used to build the library.
2190 Here is an example of creating a DLL from a source file @samp{dll.c} and
2191 also creating a program (from an object file called @samp{program.o})
2196 dlltool -e exports.o -l dll.lib dll.o
2197 gcc dll.o exports.o -o dll.dll
2198 gcc program.o dll.lib -o program
2201 The command line options have the following meanings:
2205 @item -d @var{filename}
2206 @itemx --input-def @var{filename}
2207 @cindex input .def file
2208 Specifies the name of a .def file to be read in and processed.
2210 @item -b @var{filename}
2211 @itemx --base-file @var{filename}
2213 Specifies the name of a base file to be read in and processed. The
2214 contents of this file will be added to the relocation section in the
2215 exports file generated by dlltool.
2217 @item -e @var{filename}
2218 @itemx --output-exp @var{filename}
2219 Specifies the name of the export file to be created by dlltool.
2221 @item -z @var{filename}
2222 @itemx --output-def @var{filename}
2223 Specifies the name of the .def file to be created by dlltool.
2225 @item -l @var{filename}
2226 @itemx --output-lib @var{filename}
2227 Specifies the name of the library file to be created by dlltool.
2229 @item --export-all-symbols
2230 Treat all global and weak defined symbols found in the input object
2231 files as symbols to be exported. There is a small list of symbols which
2232 are not exported by default; see the @code{--no-default-excludes}
2233 option. You may add to the list of symbols to not export by using the
2234 @code{--exclude-symbols} option.
2236 @item --no-export-all-symbols
2237 Only export symbols explicitly listed in an input .def file or in
2238 @samp{.drectve} sections in the input object files. This is the default
2239 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2240 attributes in the source code.
2242 @item --exclude-symbols @var{list}
2243 Do not export the symbols in @var{list}. This is a list of symbol names
2244 separated by comma or colon characters. The symbol names should not
2245 contain a leading underscore. This is only meaningful when
2246 @code{--export-all-symbols} is used.
2248 @item --no-default-excludes
2249 When @code{--export-all-symbols} is used, it will by default avoid
2250 exporting certain special symbols. The current list of symbols to avoid
2251 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2252 @samp{impure_ptr}. You may use the @code{--no-default-excludes} option
2253 to go ahead and export these special symbols. This is only meaningful
2254 when @code{--export-all-symbols} is used.
2257 @itemx --as @var{path}
2258 Specifies the path, including the filename, of the assembler to be used
2259 to create the exports file.
2261 @item -f @var{switches}
2262 @itemx --as-flags @var{switches}
2263 Specifies any specific command line switches to be passed to the
2264 assembler when building the exports file. This option will work even if
2265 the @samp{-S} option is not used. This option only takes one argument,
2266 and if it occurs more than once on the command line, then later
2267 occurrences will override earlier occurrences. So if it is necessary to
2268 pass multiple switches to the assembler they should be enclosed in
2272 @itemx --dll-name @var{name}
2273 Specifies the name to be stored in the .def file as the name of the DLL
2274 when the @samp{-e} option is used. If this option is not present, then
2275 the filename given to the @samp{-e} option will be used as the name of
2278 @item -m @var{machine}
2279 @itemx -machine @var{machine}
2280 Specifies the type of machine for which the library file should be
2281 built. @code{dlltool} has a built in default type, depending upon how
2282 it was created, but this option can be used to override that. This is
2283 normally only useful when creating DLLs for an ARM processor, when the
2284 contents of the DLL are actually encode using THUMB instructions.
2287 @itemx --add-indirect
2288 Specifies that when @code{dlltool} is creating the exports file it
2289 should add a section which allows the exported functions to be
2290 referenced without using the import library. Whatever the hell that
2294 @itemx --add-underscore
2295 Specifies that when @code{dlltool} is creating the exports file it
2296 should prepend an underscore to the names of the exported functions.
2300 Specifies that when @code{dlltool} is creating the exports file it
2301 should not append the string @samp{@@ <number>}. These numbers are
2302 called ordinal numbers and they represent another way of accessing the
2303 function in a DLL, other than by name.
2306 @itemx --add-stdcall-alias
2307 Specifies that when @code{dlltool} is creating the exports file it
2308 should add aliases for stdcall symbols without @samp{@@ <number>}
2309 in addition to the symbols with @samp{@@ <number>}.
2313 Specifies that when @code{dlltool} is creating the exports and library
2314 files it should omit the .idata4 section. This is for compatibility
2315 with certain operating systems.
2319 Specifies that when @code{dlltool} is creating the exports and library
2320 files it should omit the .idata5 section. This is for compatibility
2321 with certain operating systems.
2325 Specifies that @code{dlltool} should mark the objects in the library
2326 file and exports file that it produces as supporting interworking
2327 between ARM and THUMB code.
2331 Makes @code{dlltool} preserve the temporary assembler files it used to
2332 create the exports file. If this option is repeated then dlltool will
2333 also preserve the temporary object files it uses to create the library
2338 Make dlltool describe what it is doing.
2342 Displays a list of command line options and then exits.
2346 Displays dlltool's version number and then exits.
2353 @cindex ELF file information
2357 readelf [ -a | --all ]
2358 [ -h | --file-header]
2359 [ -l | --program-headers | --segments]
2360 [ -S | --section-headers | --sections]
2362 [ -s | --syms | --symbols]
2365 [ -V | --version-info]
2366 [ -D | --use-dynamic]
2367 [ -x <number> | --hex-dump=<number>]
2368 [ -w[liapr] | --debug-dump[=info,=line,=abbrev,=pubnames,=ranges]]
2372 @var{elffile}@dots{}
2375 @code{readelf} displays information about one or more ELF format object
2376 files. The options control what particular information to display.
2378 @var{elffile}@dots{} are the object files to be examined. At the
2379 moment, @code{readelf} does not support examining archives, nor does it
2380 support examing 64 bit ELF files.
2382 The long and short forms of options, shown here as alternatives, are
2383 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
2389 Equivalent to specifiying @samp{--file-header},
2390 @samp{--program-headers}, @samp{--sections}, @samp{--symbols},
2391 @samp{--relocs}, @samp{--dynamic} and @samp{--version-info}.
2394 @itemx --file-header
2395 @cindex ELF file header information
2396 Displays the information contained in the ELF header at the start of the
2400 @itemx --program-headers
2402 @cindex ELF program header information
2403 @cindex ELF segment information
2404 Displays the information contained in the file's segment headers, if it
2409 @itemx --section-headers
2410 @cindex ELF section information
2411 Displays the information contained in the file's section headers, if it
2417 @cindex ELF symbol table information
2418 Displays the entries in symbol table section of the file, if it has one.
2422 Display all the headers in the file. Equivalent to @samp{-h -l -S}.
2426 @cindex ELF reloc information
2427 Displays the contents of the file's relocation section, if it ha one.
2431 @cindex ELF dynamic section information
2432 Displays the contents of the file's dynamic section, if it has one.
2435 @itemx --version-info
2436 @cindex ELF version sections informations
2437 Displays the contents of the version sections in the file, it they
2441 @itemx --use-dynamic
2442 When displaying symbols, this option makes @code{readelf} use the
2443 symblol table in the file's dynamic section, rather than the one in the
2447 @itemx --hex-dump=<number>
2448 Displays the contents of the indicated section as a hexadecimal dump.
2451 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges]
2452 Displays the contents of the debug sections in the file, if any are
2453 present. If one of the optional letters or words follows the switch
2454 then only data found in those specific sections will be dumped.
2457 Display a histogram of bucket list lengths when displaying the contents
2458 of the symbol tables.
2462 Display the version number of readelf.
2466 Display the command line options understood by @code{readelf}.
2471 @node Selecting The Target System
2472 @chapter Selecting the target system
2474 You can specify three aspects of the target system to the @sc{gnu}
2475 binary file utilities, each in several ways:
2485 the linker emulation (which applies to the linker only)
2488 In the following summaries, the lists of ways to specify values are in
2489 order of decreasing precedence. The ways listed first override those
2492 The commands to list valid values only list the values for which the
2493 programs you are running were configured. If they were configured with
2494 @samp{--enable-targets=all}, the commands list most of the available
2495 values, but a few are left out; not all targets can be configured in at
2496 once because some of them can only be configured @dfn{native} (on hosts
2497 with the same type as the target system).
2500 * Target Selection::
2501 * Architecture Selection::
2502 * Linker Emulation Selection::
2505 @node Target Selection
2506 @section Target Selection
2508 A @dfn{target} is an object file format. A given target may be
2509 supported for multiple architectures (@pxref{Architecture Selection}).
2510 A target selection may also have variations for different operating
2511 systems or architectures.
2513 The command to list valid target values is @samp{objdump -i}
2514 (the first column of output contains the relevant information).
2516 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
2517 @samp{a.out-sunos-big}.
2519 You can also specify a target using a configuration triplet. This is
2520 the same sort of name that is passed to configure to specify a target.
2521 When you use a configuration triplet as an argument, it must be fully
2522 canonicalized. You can see the canonical version of a triplet by
2523 running the shell script @file{config.sub} which is included with the
2526 Some sample configuration triplets are: @samp{m68k-hp-bsd},
2527 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
2529 @subheading @code{objdump} Target
2535 command line option: @samp{-b} or @samp{--target}
2538 environment variable @code{GNUTARGET}
2541 deduced from the input file
2544 @subheading @code{objcopy} and @code{strip} Input Target
2550 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
2553 environment variable @code{GNUTARGET}
2556 deduced from the input file
2559 @subheading @code{objcopy} and @code{strip} Output Target
2565 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
2568 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
2571 environment variable @code{GNUTARGET}
2574 deduced from the input file
2577 @subheading @code{nm}, @code{size}, and @code{strings} Target
2583 command line option: @samp{--target}
2586 environment variable @code{GNUTARGET}
2589 deduced from the input file
2592 @subheading Linker Input Target
2598 command line option: @samp{-b} or @samp{--format}
2599 (@pxref{Options,,Options,ld.info,Using LD})
2602 script command @code{TARGET}
2603 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2606 environment variable @code{GNUTARGET}
2607 (@pxref{Environment,,Environment,ld.info,Using LD})
2610 the default target of the selected linker emulation
2611 (@pxref{Linker Emulation Selection})
2614 @subheading Linker Output Target
2620 command line option: @samp{-oformat}
2621 (@pxref{Options,,Options,ld.info,Using LD})
2624 script command @code{OUTPUT_FORMAT}
2625 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2628 the linker input target (see ``Linker Input Target'' above)
2631 @node Architecture Selection
2632 @section Architecture selection
2634 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
2635 to run. Its name may contain a colon, separating the name of the
2636 processor family from the name of the particular @sc{cpu}.
2638 The command to list valid architecture values is @samp{objdump -i} (the
2639 second column contains the relevant information).
2641 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
2643 @subheading @code{objdump} Architecture
2649 command line option: @samp{-m} or @samp{--architecture}
2652 deduced from the input file
2655 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
2661 deduced from the input file
2664 @subheading Linker Input Architecture
2670 deduced from the input file
2673 @subheading Linker Output Architecture
2679 script command @code{OUTPUT_ARCH}
2680 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2683 the default architecture from the linker output target
2684 (@pxref{Target Selection})
2687 @node Linker Emulation Selection
2688 @section Linker emulation selection
2690 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
2691 the linker default values for the other aspects of the target system.
2692 In particular, it consists of
2702 several ``hook'' functions that are run at certain stages of the linking
2703 process to do special things that some targets require
2706 The command to list valid linker emulation values is @samp{ld -V}.
2708 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
2714 command line option: @samp{-m}
2715 (@pxref{Options,,Options,ld.info,Using LD})
2718 environment variable @code{LDEMULATION}
2721 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
2722 which comes from @code{EMUL} in @file{config/@var{target}.mt}
2725 @node Reporting Bugs
2726 @chapter Reporting Bugs
2728 @cindex reporting bugs
2730 Your bug reports play an essential role in making the binary utilities
2733 Reporting a bug may help you by bringing a solution to your problem, or
2734 it may not. But in any case the principal function of a bug report is
2735 to help the entire community by making the next version of the binary
2736 utilities work better. Bug reports are your contribution to their
2739 In order for a bug report to serve its purpose, you must include the
2740 information that enables us to fix the bug.
2743 * Bug Criteria:: Have you found a bug?
2744 * Bug Reporting:: How to report bugs
2748 @section Have you found a bug?
2749 @cindex bug criteria
2751 If you are not sure whether you have found a bug, here are some guidelines:
2754 @cindex fatal signal
2757 If a binary utility gets a fatal signal, for any input whatever, that is
2758 a bug. Reliable utilities never crash.
2760 @cindex error on valid input
2762 If a binary utility produces an error message for valid input, that is a
2766 If you are an experienced user of binary utilities, your suggestions for
2767 improvement are welcome in any case.
2771 @section How to report bugs
2773 @cindex bugs, reporting
2775 A number of companies and individuals offer support for @sc{gnu}
2776 products. If you obtained the binary utilities from a support
2777 organization, we recommend you contact that organization first.
2779 You can find contact information for many support companies and
2780 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2783 In any event, we also recommend that you send bug reports for the binary
2784 utilities to @samp{bug-gnu-utils@@gnu.org}.
2786 The fundamental principle of reporting bugs usefully is this:
2787 @strong{report all the facts}. If you are not sure whether to state a
2788 fact or leave it out, state it!
2790 Often people omit facts because they think they know what causes the
2791 problem and assume that some details do not matter. Thus, you might
2792 assume that the name of a file you use in an example does not matter.
2793 Well, probably it does not, but one cannot be sure. Perhaps the bug is
2794 a stray memory reference which happens to fetch from the location where
2795 that pathname is stored in memory; perhaps, if the pathname were
2796 different, the contents of that location would fool the utility into
2797 doing the right thing despite the bug. Play it safe and give a
2798 specific, complete example. That is the easiest thing for you to do,
2799 and the most helpful.
2801 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2802 it is new to us. Therefore, always write your bug reports on the assumption
2803 that the bug has not been reported previously.
2805 Sometimes people give a few sketchy facts and ask, ``Does this ring a
2806 bell?'' Those bug reports are useless, and we urge everyone to
2807 @emph{refuse to respond to them} except to chide the sender to report
2810 To enable us to fix the bug, you should include all these things:
2814 The version of the utility. Each utility announces it if you start it
2815 with the @samp{--version} argument.
2817 Without this, we will not know whether there is any point in looking for
2818 the bug in the current version of the binary utilities.
2821 Any patches you may have applied to the source, including any patches
2822 made to the @code{BFD} library.
2825 The type of machine you are using, and the operating system name and
2829 What compiler (and its version) was used to compile the utilities---e.g.
2833 The command arguments you gave the utility to observe the bug. To
2834 guarantee you will not omit something important, list them all. A copy
2835 of the Makefile (or the output from make) is sufficient.
2837 If we were to try to guess the arguments, we would probably guess wrong
2838 and then we might not encounter the bug.
2841 A complete input file, or set of input files, that will reproduce the
2842 bug. If the utility is reading an object file or files, then it is
2843 generally most helpful to send the actual object files, uuencoded if
2844 necessary to get them through the mail system. Note that
2845 @samp{bug-gnu-utils@@gnu.org} is a mailing list, so you should avoid
2846 sending very large files to it. Making the files available for
2847 anonymous FTP is OK.
2849 If the source files were produced exclusively using @sc{gnu} programs
2850 (e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2851 may be OK to send the source files rather than the object files. In
2852 this case, be sure to say exactly what version of @code{gcc}, or
2853 whatever, was used to produce the object files. Also say how
2854 @code{gcc}, or whatever, was configured.
2857 A description of what behavior you observe that you believe is
2858 incorrect. For example, ``It gets a fatal signal.''
2860 Of course, if the bug is that the utility gets a fatal signal, then we
2861 will certainly notice it. But if the bug is incorrect output, we might
2862 not notice unless it is glaringly wrong. You might as well not give us
2863 a chance to make a mistake.
2865 Even if the problem you experience is a fatal signal, you should still
2866 say so explicitly. Suppose something strange is going on, such as, your
2867 copy of the utility is out of synch, or you have encountered a bug in
2868 the C library on your system. (This has happened!) Your copy might
2869 crash and ours would not. If you told us to expect a crash, then when
2870 ours fails to crash, we would know that the bug was not happening for
2871 us. If you had not told us to expect a crash, then we would not be able
2872 to draw any conclusion from our observations.
2875 If you wish to suggest changes to the source, send us context diffs, as
2876 generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2877 option. Always send diffs from the old file to the new file. If you
2878 even discuss something in the @code{ld} source, refer to it by context,
2881 The line numbers in our development sources will not match those in your
2882 sources. Your line numbers would convey no useful information to us.
2885 Here are some things that are not necessary:
2889 A description of the envelope of the bug.
2891 Often people who encounter a bug spend a lot of time investigating
2892 which changes to the input file will make the bug go away and which
2893 changes will not affect it.
2895 This is often time consuming and not very useful, because the way we
2896 will find the bug is by running a single example under the debugger
2897 with breakpoints, not by pure deduction from a series of examples.
2898 We recommend that you save your time for something else.
2900 Of course, if you can find a simpler example to report @emph{instead}
2901 of the original one, that is a convenience for us. Errors in the
2902 output will be easier to spot, running under the debugger will take
2903 less time, and so on.
2905 However, simplification is not vital; if you do not want to do this,
2906 report the bug anyway and send us the entire test case you used.
2909 A patch for the bug.
2911 A patch for the bug does help us if it is a good one. But do not omit
2912 the necessary information, such as the test case, on the assumption that
2913 a patch is all we need. We might see problems with your patch and decide
2914 to fix the problem another way, or we might not understand it at all.
2916 Sometimes with programs as complicated as the binary utilities it is
2917 very hard to construct an example that will make the program follow a
2918 certain path through the code. If you do not send us the example, we
2919 will not be able to construct one, so we will not be able to verify that
2922 And if we cannot understand what bug you are trying to fix, or why your
2923 patch should be an improvement, we will not install it. A test case will
2924 help us to understand.
2927 A guess about what the bug is or what it depends on.
2929 Such guesses are usually wrong. Even we cannot guess right about such
2930 things without first using the debugger to find the facts.