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1\input texinfo @c -*- Texinfo -*-
2@setfilename binutils.info
3@include config.texi
4
5@ifinfo
6@format
7START-INFO-DIR-ENTRY
ad0481cd
AS
8* Binutils: (binutils). The GNU binary utilities.
9* ar: (binutils)ar. Create, modify, and extract from archives
10* nm: (binutils)nm. List symbols from object files
11* objcopy: (binutils)objcopy. Copy and translate object files
12* objdump: (binutils)objdump. Display information from object files
13* ranlib: (binutils)ranlib. Generate index to archive contents
14* readelf: (binutils)readelf. Display the contents of ELF format files.
15* size: (binutils)size. List section sizes and total size
16* strings: (binutils)strings. List printable strings from files
17* strip: (binutils)strip. Discard symbols
18* c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
19* cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
20* addr2line: (binutils)addr2line. Convert addresses to file and line
21* nlmconv: (binutils)nlmconv. Converts object code into an NLM
22* windres: (binutils)windres. Manipulate Windows resources
23* dlltool: (binutils)dlltool. Create files needed to build and use DLLs
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24END-INFO-DIR-ENTRY
25@end format
26@end ifinfo
27
28@ifinfo
8f915f68 29Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
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30
31Permission is granted to make and distribute verbatim copies of
32this manual provided the copyright notice and this permission notice
33are preserved on all copies.
34
35@ignore
36Permission is granted to process this file through TeX and print the
37results, provided the printed document carries a copying permission
38notice identical to this one except for the removal of this paragraph
39(this paragraph not being relevant to the printed manual).
40
41@end ignore
42
43Permission is granted to copy and distribute modified versions of this
44manual under the conditions for verbatim copying, provided also that
45the entire resulting derived work is distributed under the terms of a
46permission notice identical to this one.
47
48Permission is granted to copy and distribute translations of this manual
49into another language, under the above conditions for modified versions.
50@end ifinfo
51
52@synindex ky cp
53@c
54@c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55@c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
56@c
8f915f68 57@c Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc.
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58@c
59@c This text may be freely distributed under the terms of the GNU
60@c General Public License.
61@c
62
63@setchapternewpage odd
64@settitle @sc{gnu} Binary Utilities
65@titlepage
66@finalout
67@title The @sc{gnu} Binary Utilities
68@subtitle Version @value{VERSION}
69@sp 1
70@subtitle May 1993
71@author Roland H. Pesch
72@author Jeffrey M. Osier
73@author Cygnus Support
74@page
75
76@tex
77{\parskip=0pt \hfill Cygnus Support\par \hfill
78\TeX{}info \texinfoversion\par }
79@end tex
80
81@vskip 0pt plus 1filll
82Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
83
84Permission is granted to make and distribute verbatim copies of
85this manual provided the copyright notice and this permission notice
86are preserved on all copies.
87
88Permission is granted to copy and distribute modified versions of this
89manual under the conditions for verbatim copying, provided also that
90the entire resulting derived work is distributed under the terms of a
91permission notice identical to this one.
92
93Permission is granted to copy and distribute translations of this manual
94into another language, under the above conditions for modified versions.
95@end titlepage
96
97@node Top
98@top Introduction
99
100@cindex version
101This brief manual contains preliminary documentation for the @sc{gnu} binary
102utilities (collectively version @value{VERSION}):
103
104@iftex
105@table @code
106@item ar
107Create, modify, and extract from archives
108
109@item nm
110List symbols from object files
111
112@item objcopy
113Copy and translate object files
114
115@item objdump
116Display information from object files
117
118@item ranlib
119Generate index to archive contents
120
121@item readelf
122Display the contents of ELF format files.
123
124@item size
125List file section sizes and total size
126
127@item strings
128List printable strings from files
129
130@item strip
131Discard symbols
132
133@item c++filt
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134Demangle encoded C++ symbols (on MS-DOS, this program is named
135@code{cxxfilt})
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136
137@item addr2line
138Convert addresses into file names and line numbers
139
140@item nlmconv
141Convert object code into a Netware Loadable Module
142
143@item windres
144Manipulate Windows resources
145
146@item dlltool
147Create the files needed to build and use Dynamic Link Libraries
148@end table
149@end iftex
150
151@menu
152* ar:: Create, modify, and extract from archives
153* nm:: List symbols from object files
154* objcopy:: Copy and translate object files
155* objdump:: Display information from object files
156* ranlib:: Generate index to archive contents
157* readelf:: Display the contents of ELF format files.
158* size:: List section sizes and total size
159* strings:: List printable strings from files
160* strip:: Discard symbols
161* c++filt:: Filter to demangle encoded C++ symbols
9d51cc66 162* cxxfilt: c++filt. MS-DOS name for c++filt
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163* addr2line:: Convert addresses to file and line
164* nlmconv:: Converts object code into an NLM
165* windres:: Manipulate Windows resources
166* dlltool:: Create files needed to build and use DLLs
167* Selecting The Target System:: How these utilities determine the target.
168* Reporting Bugs:: Reporting Bugs
169* Index:: Index
170@end menu
171
172@node ar
173@chapter ar
174
175@kindex ar
176@cindex archives
177@cindex collections of files
178@smallexample
3de39064 179ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
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180ar -M [ <mri-script ]
181@end smallexample
182
183The @sc{gnu} @code{ar} program creates, modifies, and extracts from
184archives. An @dfn{archive} is a single file holding a collection of
185other files in a structure that makes it possible to retrieve
186the original individual files (called @dfn{members} of the archive).
187
188The original files' contents, mode (permissions), timestamp, owner, and
189group are preserved in the archive, and can be restored on
190extraction.
191
192@cindex name length
193@sc{gnu} @code{ar} can maintain archives whose members have names of any
194length; however, depending on how @code{ar} is configured on your
195system, a limit on member-name length may be imposed for compatibility
196with archive formats maintained with other tools. If it exists, the
197limit is often 15 characters (typical of formats related to a.out) or 16
198characters (typical of formats related to coff).
199
200@cindex libraries
201@code{ar} is considered a binary utility because archives of this sort
202are most often used as @dfn{libraries} holding commonly needed
203subroutines.
204
205@cindex symbol index
206@code{ar} creates an index to the symbols defined in relocatable
207object modules in the archive when you specify the modifier @samp{s}.
208Once created, this index is updated in the archive whenever @code{ar}
209makes a change to its contents (save for the @samp{q} update operation).
210An archive with such an index speeds up linking to the library, and
211allows routines in the library to call each other without regard to
212their placement in the archive.
213
214You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
215table. If an archive lacks the table, another form of @code{ar} called
216@code{ranlib} can be used to add just the table.
217
218@cindex compatibility, @code{ar}
219@cindex @code{ar} compatibility
220@sc{gnu} @code{ar} is designed to be compatible with two different
221facilities. You can control its activity using command-line options,
222like the different varieties of @code{ar} on Unix systems; or, if you
223specify the single command-line option @samp{-M}, you can control it
224with a script supplied via standard input, like the MRI ``librarian''
225program.
226
227@menu
228* ar cmdline:: Controlling @code{ar} on the command line
229* ar scripts:: Controlling @code{ar} with a script
230@end menu
231
232@page
233@node ar cmdline
234@section Controlling @code{ar} on the command line
235
236@smallexample
3de39064 237ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
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238@end smallexample
239
240@cindex Unix compatibility, @code{ar}
241When you use @code{ar} in the Unix style, @code{ar} insists on at least two
242arguments to execute: one keyletter specifying the @emph{operation}
243(optionally accompanied by other keyletters specifying
244@emph{modifiers}), and the archive name to act on.
245
246Most operations can also accept further @var{member} arguments,
247specifying particular files to operate on.
248
249@sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
250flags @var{mod} in any order, within the first command-line argument.
251
252If you wish, you may begin the first command-line argument with a
253dash.
254
255@cindex operations on archive
256The @var{p} keyletter specifies what operation to execute; it may be
257any of the following, but you must specify only one of them:
258
259@table @code
260@item d
261@cindex deleting from archive
262@emph{Delete} modules from the archive. Specify the names of modules to
263be deleted as @var{member}@dots{}; the archive is untouched if you
264specify no files to delete.
265
266If you specify the @samp{v} modifier, @code{ar} lists each module
267as it is deleted.
268
269@item m
270@cindex moving in archive
271Use this operation to @emph{move} members in an archive.
272
273The ordering of members in an archive can make a difference in how
274programs are linked using the library, if a symbol is defined in more
275than one member.
276
277If no modifiers are used with @code{m}, any members you name in the
278@var{member} arguments are moved to the @emph{end} of the archive;
279you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
280specified place instead.
281
282@item p
283@cindex printing from archive
284@emph{Print} the specified members of the archive, to the standard
285output file. If the @samp{v} modifier is specified, show the member
286name before copying its contents to standard output.
287
288If you specify no @var{member} arguments, all the files in the archive are
289printed.
290
291@item q
292@cindex quick append to archive
293@emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
294@var{archive}, without checking for replacement.
295
296The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
297operation; new members are always placed at the end of the archive.
298
299The modifier @samp{v} makes @code{ar} list each file as it is appended.
300
301Since the point of this operation is speed, the archive's symbol table
302index is not updated, even if it already existed; you can use @samp{ar s} or
303@code{ranlib} explicitly to update the symbol table index.
304
305However, too many different systems assume quick append rebuilds the
306index, so GNU ar implements @code{q} as a synonym for @code{r}.
307
308@item r
309@cindex replacement in archive
310Insert the files @var{member}@dots{} into @var{archive} (with
311@emph{replacement}). This operation differs from @samp{q} in that any
312previously existing members are deleted if their names match those being
313added.
314
315If one of the files named in @var{member}@dots{} does not exist, @code{ar}
316displays an error message, and leaves undisturbed any existing members
317of the archive matching that name.
318
319By default, new members are added at the end of the file; but you may
320use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
321placement relative to some existing member.
322
323The modifier @samp{v} used with this operation elicits a line of
324output for each file inserted, along with one of the letters @samp{a} or
325@samp{r} to indicate whether the file was appended (no old member
326deleted) or replaced.
327
328@item t
329@cindex contents of archive
330Display a @emph{table} listing the contents of @var{archive}, or those
331of the files listed in @var{member}@dots{} that are present in the
332archive. Normally only the member name is shown; if you also want to
333see the modes (permissions), timestamp, owner, group, and size, you can
334request that by also specifying the @samp{v} modifier.
335
336If you do not specify a @var{member}, all files in the archive
337are listed.
338
339@cindex repeated names in archive
340@cindex name duplication in archive
341If there is more than one file with the same name (say, @samp{fie}) in
342an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
343first instance; to see them all, you must ask for a complete
344listing---in our example, @samp{ar t b.a}.
345@c WRS only; per Gumby, this is implementation-dependent, and in a more
346@c recent case in fact works the other way.
347
348@item x
349@cindex extract from archive
350@emph{Extract} members (named @var{member}) from the archive. You can
351use the @samp{v} modifier with this operation, to request that
352@code{ar} list each name as it extracts it.
353
354If you do not specify a @var{member}, all files in the archive
355are extracted.
356
357@end table
358
359A number of modifiers (@var{mod}) may immediately follow the @var{p}
360keyletter, to specify variations on an operation's behavior:
361
362@table @code
363@item a
364@cindex relative placement in archive
365Add new files @emph{after} an existing member of the
366archive. If you use the modifier @samp{a}, the name of an existing archive
367member must be present as the @var{relpos} argument, before the
368@var{archive} specification.
369
370@item b
371Add new files @emph{before} an existing member of the
372archive. If you use the modifier @samp{b}, the name of an existing archive
373member must be present as the @var{relpos} argument, before the
374@var{archive} specification. (same as @samp{i}).
375
376@item c
377@cindex creating archives
378@emph{Create} the archive. The specified @var{archive} is always
379created if it did not exist, when you request an update. But a warning is
380issued unless you specify in advance that you expect to create it, by
381using this modifier.
382
383@item f
384Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
385names of any length. This will cause it to create archives which are
386not compatible with the native @code{ar} program on some systems. If
387this is a concern, the @samp{f} modifier may be used to truncate file
388names when putting them in the archive.
389
390@item i
391Insert new files @emph{before} an existing member of the
392archive. If you use the modifier @samp{i}, the name of an existing archive
393member must be present as the @var{relpos} argument, before the
394@var{archive} specification. (same as @samp{b}).
395
396@item l
397This modifier is accepted but not used.
398@c whaffor ar l modifier??? presumably compat; with
399@c what???---doc@@cygnus.com, 25jan91
400
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401@item N
402Uses the @var{count} parameter. This is used if there are multiple
403entries in the archive with the same name. Extract or delete instance
404@var{count} of the given name from the archive.
405
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406@item o
407@cindex dates in archive
408Preserve the @emph{original} dates of members when extracting them. If
409you do not specify this modifier, files extracted from the archive
410are stamped with the time of extraction.
411
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412@item P
413Use the full path name when matching names in the archive. @sc{gnu}
414@code{ar} can not create an archive with a full path name (such archives
415are not POSIX complaint), but other archive creators can. This option
416will cause @sc{gnu} @code{ar} to match file names using a complete path
417name, which can be convenient when extracting a single file from an
418archive created by another tool.
419
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420@item s
421@cindex writing archive index
422Write an object-file index into the archive, or update an existing one,
423even if no other change is made to the archive. You may use this modifier
424flag either with any operation, or alone. Running @samp{ar s} on an
425archive is equivalent to running @samp{ranlib} on it.
426
427@item S
428@cindex not writing archive index
429Do not generate an archive symbol table. This can speed up building a
430large library in several steps. The resulting archive can not be used
431with the linker. In order to build a symbol table, you must omit the
432@samp{S} modifier on the last execution of @samp{ar}, or you must run
433@samp{ranlib} on the archive.
434
435@item u
436@cindex updating an archive
437Normally, @samp{ar r}@dots{} inserts all files
438listed into the archive. If you would like to insert @emph{only} those
439of the files you list that are newer than existing members of the same
440names, use this modifier. The @samp{u} modifier is allowed only for the
441operation @samp{r} (replace). In particular, the combination @samp{qu} is
442not allowed, since checking the timestamps would lose any speed
443advantage from the operation @samp{q}.
444
445@item v
446This modifier requests the @emph{verbose} version of an operation. Many
447operations display additional information, such as filenames processed,
448when the modifier @samp{v} is appended.
449
450@item V
451This modifier shows the version number of @code{ar}.
452@end table
453
454@node ar scripts
455@section Controlling @code{ar} with a script
456
457@smallexample
458ar -M [ <@var{script} ]
459@end smallexample
460
461@cindex MRI compatibility, @code{ar}
462@cindex scripts, @code{ar}
463If you use the single command-line option @samp{-M} with @code{ar}, you
464can control its operation with a rudimentary command language. This
465form of @code{ar} operates interactively if standard input is coming
466directly from a terminal. During interactive use, @code{ar} prompts for
467input (the prompt is @samp{AR >}), and continues executing even after
468errors. If you redirect standard input to a script file, no prompts are
469issued, and @code{ar} abandons execution (with a nonzero exit code)
470on any error.
471
472The @code{ar} command language is @emph{not} designed to be equivalent
473to the command-line options; in fact, it provides somewhat less control
474over archives. The only purpose of the command language is to ease the
475transition to @sc{gnu} @code{ar} for developers who already have scripts
476written for the MRI ``librarian'' program.
477
478The syntax for the @code{ar} command language is straightforward:
479@itemize @bullet
480@item
481commands are recognized in upper or lower case; for example, @code{LIST}
482is the same as @code{list}. In the following descriptions, commands are
483shown in upper case for clarity.
484
485@item
486a single command may appear on each line; it is the first word on the
487line.
488
489@item
490empty lines are allowed, and have no effect.
491
492@item
493comments are allowed; text after either of the characters @samp{*}
494or @samp{;} is ignored.
495
496@item
497Whenever you use a list of names as part of the argument to an @code{ar}
498command, you can separate the individual names with either commas or
499blanks. Commas are shown in the explanations below, for clarity.
500
501@item
502@samp{+} is used as a line continuation character; if @samp{+} appears
503at the end of a line, the text on the following line is considered part
504of the current command.
505@end itemize
506
507Here are the commands you can use in @code{ar} scripts, or when using
508@code{ar} interactively. Three of them have special significance:
509
510@code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
511a temporary file required for most of the other commands.
512
513@code{SAVE} commits the changes so far specified by the script. Prior
514to @code{SAVE}, commands affect only the temporary copy of the current
515archive.
516
517@table @code
518@item ADDLIB @var{archive}
519@itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
520Add all the contents of @var{archive} (or, if specified, each named
521@var{module} from @var{archive}) to the current archive.
522
523Requires prior use of @code{OPEN} or @code{CREATE}.
524
525@item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
526@c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
527@c else like "ar q..."
528Add each named @var{member} as a module in the current archive.
529
530Requires prior use of @code{OPEN} or @code{CREATE}.
531
532@item CLEAR
533Discard the contents of the current archive, canceling the effect of
534any operations since the last @code{SAVE}. May be executed (with no
535effect) even if no current archive is specified.
536
537@item CREATE @var{archive}
538Creates an archive, and makes it the current archive (required for many
539other commands). The new archive is created with a temporary name; it
540is not actually saved as @var{archive} until you use @code{SAVE}.
541You can overwrite existing archives; similarly, the contents of any
542existing file named @var{archive} will not be destroyed until @code{SAVE}.
543
544@item DELETE @var{module}, @var{module}, @dots{} @var{module}
545Delete each listed @var{module} from the current archive; equivalent to
546@samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
547
548Requires prior use of @code{OPEN} or @code{CREATE}.
549
550@item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
551@itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
552List each named @var{module} present in @var{archive}. The separate
553command @code{VERBOSE} specifies the form of the output: when verbose
554output is off, output is like that of @samp{ar -t @var{archive}
555@var{module}@dots{}}. When verbose output is on, the listing is like
556@samp{ar -tv @var{archive} @var{module}@dots{}}.
557
558Output normally goes to the standard output stream; however, if you
559specify @var{outputfile} as a final argument, @code{ar} directs the
560output to that file.
561
562@item END
563Exit from @code{ar}, with a @code{0} exit code to indicate successful
564completion. This command does not save the output file; if you have
565changed the current archive since the last @code{SAVE} command, those
566changes are lost.
567
568@item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
569Extract each named @var{module} from the current archive, writing them
570into the current directory as separate files. Equivalent to @samp{ar -x
571@var{archive} @var{module}@dots{}}.
572
573Requires prior use of @code{OPEN} or @code{CREATE}.
574
575@ignore
576@c FIXME Tokens but no commands???
577@item FULLDIR
578
579@item HELP
580@end ignore
581
582@item LIST
583Display full contents of the current archive, in ``verbose'' style
584regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
c89746f6 585tv @var{archive}}. (This single command is a @sc{gnu} @code{ar}
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586enhancement, rather than present for MRI compatibility.)
587
588Requires prior use of @code{OPEN} or @code{CREATE}.
589
590@item OPEN @var{archive}
591Opens an existing archive for use as the current archive (required for
592many other commands). Any changes as the result of subsequent commands
593will not actually affect @var{archive} until you next use @code{SAVE}.
594
595@item REPLACE @var{module}, @var{module}, @dots{} @var{module}
596In the current archive, replace each existing @var{module} (named in
597the @code{REPLACE} arguments) from files in the current working directory.
598To execute this command without errors, both the file, and the module in
599the current archive, must exist.
600
601Requires prior use of @code{OPEN} or @code{CREATE}.
602
603@item VERBOSE
604Toggle an internal flag governing the output from @code{DIRECTORY}.
605When the flag is on, @code{DIRECTORY} output matches output from
606@samp{ar -tv }@dots{}.
607
608@item SAVE
609Commit your changes to the current archive, and actually save it as a
610file with the name specified in the last @code{CREATE} or @code{OPEN}
611command.
612
613Requires prior use of @code{OPEN} or @code{CREATE}.
614
615@end table
616
617@iftex
618@node ld
619@chapter ld
620@cindex linker
621@kindex ld
622The @sc{gnu} linker @code{ld} is now described in a separate manual.
623@xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
624@end iftex
625
626@node nm
627@chapter nm
628@cindex symbols
629@kindex nm
630
631@smallexample
632nm [ -a | --debug-syms ] [ -g | --extern-only ]
633 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
634 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
635 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
636 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
637 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
638 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
639 [ --defined-only ] [-l | --line-numbers ]
640 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
641@end smallexample
642
643@sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
f20a759a 644If no object files are listed as arguments, @code{nm} assumes the file
252b5132
RH
645@file{a.out}.
646
647For each symbol, @code{nm} shows:
648
649@itemize @bullet
650@item
651The symbol value, in the radix selected by options (see below), or
652hexadecimal by default.
653
654@item
655The symbol type. At least the following types are used; others are, as
656well, depending on the object file format. If lowercase, the symbol is
657local; if uppercase, the symbol is global (external).
658
659@c Some more detail on exactly what these symbol types are used for
660@c would be nice.
661@table @code
662@item A
663The symbol's value is absolute, and will not be changed by further
664linking.
665
666@item B
667The symbol is in the uninitialized data section (known as BSS).
668
669@item C
670The symbol is common. Common symbols are uninitialized data. When
671linking, multiple common symbols may appear with the same name. If the
672symbol is defined anywhere, the common symbols are treated as undefined
673references. For more details on common symbols, see the discussion of
674--warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
675
676@item D
677The symbol is in the initialized data section.
678
679@item G
680The symbol is in an initialized data section for small objects. Some
681object file formats permit more efficient access to small data objects,
682such as a global int variable as opposed to a large global array.
683
684@item I
685The symbol is an indirect reference to another symbol. This is a GNU
686extension to the a.out object file format which is rarely used.
687
688@item N
689The symbol is a debugging symbol.
690
691@item R
692The symbol is in a read only data section.
693
694@item S
695The symbol is in an uninitialized data section for small objects.
696
697@item T
698The symbol is in the text (code) section.
699
700@item U
701The symbol is undefined.
702
703@item W
704The symbol is weak. When a weak defined symbol is linked with a normal
705defined symbol, the normal defined symbol is used with no error. When a
706weak undefined symbol is linked and the symbol is not defined, the value
707of the weak symbol becomes zero with no error.
708
709@item -
710The symbol is a stabs symbol in an a.out object file. In this case, the
711next values printed are the stabs other field, the stabs desc field, and
712the stab type. Stabs symbols are used to hold debugging information;
713for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
714``stabs'' debug format}.
715
716@item ?
717The symbol type is unknown, or object file format specific.
718@end table
719
720@item
721The symbol name.
722@end itemize
723
724The long and short forms of options, shown here as alternatives, are
725equivalent.
726
727@table @code
728@item -A
729@itemx -o
730@itemx --print-file-name
731@cindex input file name
732@cindex file name
733@cindex source file name
f20a759a 734Precede each symbol by the name of the input file (or archive member)
252b5132
RH
735in which it was found, rather than identifying the input file once only,
736before all of its symbols.
737
738@item -a
739@itemx --debug-syms
740@cindex debugging symbols
741Display all symbols, even debugger-only symbols; normally these are not
742listed.
743
744@item -B
745@cindex @code{nm} format
746@cindex @code{nm} compatibility
747The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
748
749@item -C
750@itemx --demangle
751@cindex demangling in nm
752Decode (@dfn{demangle}) low-level symbol names into user-level names.
753Besides removing any initial underscore prepended by the system, this
754makes C++ function names readable. @xref{c++filt}, for more information
755on demangling.
756
757@item --no-demangle
758Do not demangle low-level symbol names. This is the default.
759
760@item -D
761@itemx --dynamic
762@cindex dynamic symbols
763Display the dynamic symbols rather than the normal symbols. This is
764only meaningful for dynamic objects, such as certain types of shared
765libraries.
766
767@item -f @var{format}
768@itemx --format=@var{format}
769@cindex @code{nm} format
770@cindex @code{nm} compatibility
771Use the output format @var{format}, which can be @code{bsd},
772@code{sysv}, or @code{posix}. The default is @code{bsd}.
773Only the first character of @var{format} is significant; it can be
774either upper or lower case.
775
776@item -g
777@itemx --extern-only
778@cindex external symbols
779Display only external symbols.
780
781@item -l
782@itemx --line-numbers
783@cindex symbol line numbers
784For each symbol, use debugging information to try to find a filename and
785line number. For a defined symbol, look for the line number of the
786address of the symbol. For an undefined symbol, look for the line
787number of a relocation entry which refers to the symbol. If line number
788information can be found, print it after the other symbol information.
789
790@item -n
791@itemx -v
792@itemx --numeric-sort
793Sort symbols numerically by their addresses, rather than alphabetically
794by their names.
795
796@item -p
797@itemx --no-sort
798@cindex sorting symbols
799Do not bother to sort the symbols in any order; print them in the order
800encountered.
801
802@item -P
803@itemx --portability
804Use the POSIX.2 standard output format instead of the default format.
805Equivalent to @samp{-f posix}.
806
807@item -s
808@itemx --print-armap
809@cindex symbol index, listing
810When listing symbols from archive members, include the index: a mapping
811(stored in the archive by @code{ar} or @code{ranlib}) of which modules
812contain definitions for which names.
813
814@item -r
815@itemx --reverse-sort
816Reverse the order of the sort (whether numeric or alphabetic); let the
817last come first.
818
819@item --size-sort
820Sort symbols by size. The size is computed as the difference between
821the value of the symbol and the value of the symbol with the next higher
822value. The size of the symbol is printed, rather than the value.
823
824@item -t @var{radix}
825@itemx --radix=@var{radix}
826Use @var{radix} as the radix for printing the symbol values. It must be
827@samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
828
829@item --target=@var{bfdname}
830@cindex object code format
831Specify an object code format other than your system's default format.
832@xref{Target Selection}, for more information.
833
834@item -u
835@itemx --undefined-only
836@cindex external symbols
837@cindex undefined symbols
838Display only undefined symbols (those external to each object file).
839
840@item --defined-only
841@cindex external symbols
842@cindex undefined symbols
843Display only defined symbols for each object file.
844
845@item -V
846@itemx --version
847Show the version number of @code{nm} and exit.
848
849@item --help
850Show a summary of the options to @code{nm} and exit.
851@end table
852
853@node objcopy
854@chapter objcopy
855
856@smallexample
857objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
858 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
859 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
860 [ -S | --strip-all ] [ -g | --strip-debug ]
861 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
862 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
863 [ -L @var{symbolname} | --localize-symbol=@var{symbolname} ]
864 [ -W @var{symbolname} | --weaken-symbol=@var{symbolname} ]
865 [ -x | --discard-all ] [ -X | --discard-locals ]
866 [ -b @var{byte} | --byte=@var{byte} ]
867 [ -i @var{interleave} | --interleave=@var{interleave} ]
f91ea849 868 [ -j @var{sectionname} | --only-section=@var{sectionname} ]
252b5132
RH
869 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
870 [ -p | --preserve-dates ] [ --debugging ]
871 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
872 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
873 [ --change-addresses=@var{incr} ]
874 [ --change-section-address=@var{section}@{=,+,-@}@var{val} ]
875 [ --change-section-lma=@var{section}@{=,+,-@}@var{val} ]
876 [ --change-section-vma=@var{section}@{=,+,-@}@var{val} ]
877 [ --change-warnings ] [ --no-change-warnings ]
878 [ --set-section-flags=@var{section}=@var{flags} ]
879 [ --add-section=@var{sectionname}=@var{filename} ]
880 [ --change-leading-char ] [ --remove-leading-char ]
881 [ --weaken ]
882 [ -v | --verbose ] [ -V | --version ] [ --help ]
883 @var{infile} [@var{outfile}]
884@end smallexample
885
886The @sc{gnu} @code{objcopy} utility copies the contents of an object
887file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
888read and write the object files. It can write the destination object
889file in a format different from that of the source object file. The
890exact behavior of @code{objcopy} is controlled by command-line options.
891
892@code{objcopy} creates temporary files to do its translations and
893deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
894translation work; it has access to all the formats described in @sc{bfd}
895and thus is able to recognize most formats without being told
896explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
897
898@code{objcopy} can be used to generate S-records by using an output
899target of @samp{srec} (e.g., use @samp{-O srec}).
900
901@code{objcopy} can be used to generate a raw binary file by using an
902output target of @samp{binary} (e.g., use @samp{-O binary}). When
903@code{objcopy} generates a raw binary file, it will essentially produce
904a memory dump of the contents of the input object file. All symbols and
905relocation information will be discarded. The memory dump will start at
906the load address of the lowest section copied into the output file.
907
908When generating an S-record or a raw binary file, it may be helpful to
909use @samp{-S} to remove sections containing debugging information. In
910some cases @samp{-R} will be useful to remove sections which contain
f20a759a 911information that is not needed by the binary file.
252b5132
RH
912
913@table @code
914@item @var{infile}
915@itemx @var{outfile}
f20a759a 916The input and output files, respectively.
252b5132
RH
917If you do not specify @var{outfile}, @code{objcopy} creates a
918temporary file and destructively renames the result with
919the name of @var{infile}.
920
921@item -I @var{bfdname}
922@itemx --input-target=@var{bfdname}
923Consider the source file's object format to be @var{bfdname}, rather than
924attempting to deduce it. @xref{Target Selection}, for more information.
925
926@item -O @var{bfdname}
927@itemx --output-target=@var{bfdname}
928Write the output file using the object format @var{bfdname}.
929@xref{Target Selection}, for more information.
930
931@item -F @var{bfdname}
932@itemx --target=@var{bfdname}
933Use @var{bfdname} as the object format for both the input and the output
934file; i.e., simply transfer data from source to destination with no
935translation. @xref{Target Selection}, for more information.
936
f91ea849
ILT
937@item -j @var{sectionname}
938@itemx --only-section=@var{sectionname}
939Copy only the named section from the input file to the output file.
940This option may be given more than once. Note that using this option
941inappropriately may make the output file unusable.
942
252b5132
RH
943@item -R @var{sectionname}
944@itemx --remove-section=@var{sectionname}
945Remove any section named @var{sectionname} from the output file. This
946option may be given more than once. Note that using this option
947inappropriately may make the output file unusable.
948
949@item -S
950@itemx --strip-all
951Do not copy relocation and symbol information from the source file.
952
953@item -g
954@itemx --strip-debug
955Do not copy debugging symbols from the source file.
956
957@item --strip-unneeded
958Strip all symbols that are not needed for relocation processing.
959
960@item -K @var{symbolname}
961@itemx --keep-symbol=@var{symbolname}
962Copy only symbol @var{symbolname} from the source file. This option may
963be given more than once.
964
965@item -N @var{symbolname}
966@itemx --strip-symbol=@var{symbolname}
967Do not copy symbol @var{symbolname} from the source file. This option
968may be given more than once.
969
970@item -L @var{symbolname}
971@itemx --localize-symbol=@var{symbolname}
972Make symbol @var{symbolname} local to the file, so that it is not
973visible externally. This option may be given more than once.
974
975@item -W @var{symbolname}
976@itemx --weaken-symbol=@var{symbolname}
977Make symbol @var{symbolname} weak. This option may be given more than once.
978
979@item -x
980@itemx --discard-all
981Do not copy non-global symbols from the source file.
982@c FIXME any reason to prefer "non-global" to "local" here?
983
984@item -X
985@itemx --discard-locals
986Do not copy compiler-generated local symbols.
987(These usually start with @samp{L} or @samp{.}.)
988
989@item -b @var{byte}
990@itemx --byte=@var{byte}
991Keep only every @var{byte}th byte of the input file (header data is not
992affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
993where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
994option, or the default of 4. This option is useful for creating files
995to program @sc{rom}. It is typically used with an @code{srec} output
996target.
997
998@item -i @var{interleave}
999@itemx --interleave=@var{interleave}
1000Only copy one out of every @var{interleave} bytes. Select which byte to
1001copy with the @var{-b} or @samp{--byte} option. The default is 4.
1002@code{objcopy} ignores this option if you do not specify either @samp{-b} or
1003@samp{--byte}.
1004
1005@item -p
1006@itemx --preserve-dates
1007Set the access and modification dates of the output file to be the same
1008as those of the input file.
1009
1010@item --debugging
1011Convert debugging information, if possible. This is not the default
1012because only certain debugging formats are supported, and the
1013conversion process can be time consuming.
1014
1015@item --gap-fill @var{val}
1016Fill gaps between sections with @var{val}. This operation applies to
1017the @emph{load address} (LMA) of the sections. It is done by increasing
1018the size of the section with the lower address, and filling in the extra
1019space created with @var{val}.
1020
1021@item --pad-to @var{address}
1022Pad the output file up to the load address @var{address}. This is
1023done by increasing the size of the last section. The extra space is
1024filled in with the value specified by @samp{--gap-fill} (default zero).
1025
1026@item --set-start @var{val}
f20a759a 1027Set the start address of the new file to @var{val}. Not all object file
252b5132
RH
1028formats support setting the start address.
1029
1030@item --change-start @var{incr}
1031@itemx --adjust-start @var{incr}
1032@cindex changing start address
1033Change the start address by adding @var{incr}. Not all object file
1034formats support setting the start address.
1035
1036@item --change-addresses @var{incr}
1037@itemx --adjust-vma @var{incr}
1038@cindex changing object addresses
1039Change the VMA and LMA addresses of all sections, as well as the start
1040address, by adding @var{incr}. Some object file formats do not permit
1041section addresses to be changed arbitrarily. Note that this does not
1042relocate the sections; if the program expects sections to be loaded at a
1043certain address, and this option is used to change the sections such
1044that they are loaded at a different address, the program may fail.
1045
1046@item --change-section-address @var{section}@{=,+,-@}@var{val}
1047@itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1048@cindex changing section address
1049Set or change both the VMA address and the LMA address of the named
1050@var{section}. If @samp{=} is used, the section address is set to
1051@var{val}. Otherwise, @var{val} is added to or subtracted from the
1052section address. See the comments under @samp{--change-addresses},
1053above. If @var{section} does not exist in the input file, a warning will
1054be issued, unless @samp{--no-change-warnings} is used.
1055
1056@item --change-section-lma @var{section}@{=,+,-@}@var{val}
1057@cindex changing section LMA
1058Set or change the LMA address of the named @var{section}. The LMA
1059address is the address where the section will be loaded into memory at
1060program load time. Normally this is the same as the VMA address, which
1061is the address of the section at program run time, but on some systems,
1062especially those where a program is held in ROM, the two can be
1063different. If @samp{=} is used, the section address is set to
1064@var{val}. Otherwise, @var{val} is added to or subtracted from the
1065section address. See the comments under @samp{--change-addresses},
1066above. If @var{section} does not exist in the input file, a warning
1067will be issued, unless @samp{--no-change-warnings} is used.
1068
1069@item --change-section-vma @var{section}@{=,+,-@}@var{val}
1070@cindex changing section VMA
1071Set or change the VMA address of the named @var{section}. The VMA
1072address is the address where the section will be located once the
1073program has started executing. Normally this is the same as the LMA
1074address, which is the address where the section will be loaded into
1075memory, but on some systems, especially those where a program is held in
1076ROM, the two can be different. If @samp{=} is used, the section address
1077is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1078from the section address. See the comments under
1079@samp{--change-addresses}, above. If @var{section} does not exist in
1080the input file, a warning will be issued, unless
1081@samp{--no-change-warnings} is used.
1082
1083@item --change-warnings
1084@itemx --adjust-warnings
1085If @samp{--change-section-address} or @samp{--change-section-lma} or
1086@samp{--change-section-vma} is used, and the named section does not
1087exist, issue a warning. This is the default.
1088
1089@item --no-change-warnings
1090@itemx --no-adjust-warnings
1091Do not issue a warning if @samp{--change-section-address} or
1092@samp{--adjust-section-lma} or @samp{--adjust-section-vma} is used, even
1093if the named section does not exist.
1094
1095@item --set-section-flags @var{section}=@var{flags}
1096Set the flags for the named section. The @var{flags} argument is a
1097comma separated string of flag names. The recognized names are
3994e2c6
ILT
1098@samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1099@samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1100@samp{debug}. You can set the @samp{contents} flag for a section which
1101does not have contents, but it is not meaningful to clear the
1102@samp{contents} flag of a section which does have contents--just remove
1103the section instead. Not all flags are meaningful for all object file
1104formats.
252b5132
RH
1105
1106@item --add-section @var{sectionname}=@var{filename}
1107Add a new section named @var{sectionname} while copying the file. The
1108contents of the new section are taken from the file @var{filename}. The
1109size of the section will be the size of the file. This option only
1110works on file formats which can support sections with arbitrary names.
1111
1112@item --change-leading-char
1113Some object file formats use special characters at the start of
1114symbols. The most common such character is underscore, which compilers
1115often add before every symbol. This option tells @code{objcopy} to
1116change the leading character of every symbol when it converts between
1117object file formats. If the object file formats use the same leading
1118character, this option has no effect. Otherwise, it will add a
1119character, or remove a character, or change a character, as
1120appropriate.
1121
1122@item --remove-leading-char
1123If the first character of a global symbol is a special symbol leading
1124character used by the object file format, remove the character. The
1125most common symbol leading character is underscore. This option will
1126remove a leading underscore from all global symbols. This can be useful
1127if you want to link together objects of different file formats with
1128different conventions for symbol names. This is different from
1129@code{--change-leading-char} because it always changes the symbol name
1130when appropriate, regardless of the object file format of the output
1131file.
1132
1133@item --weaken
1134Change all global symbols in the file to be weak. This can be useful
1135when building an object which will be linked against other objects using
1136the @code{-R} option to the linker. This option is only effective when
1137using an object file format which supports weak symbols.
1138
1139@item -V
1140@itemx --version
1141Show the version number of @code{objcopy}.
1142
1143@item -v
1144@itemx --verbose
1145Verbose output: list all object files modified. In the case of
1146archives, @samp{objcopy -V} lists all members of the archive.
1147
1148@item --help
1149Show a summary of the options to @code{objcopy}.
1150@end table
1151
1152@node objdump
1153@chapter objdump
1154
1155@cindex object file information
1156@kindex objdump
1157
1158@smallexample
1159objdump [ -a | --archive-headers ]
1dada9c5
NC
1160 [ -b @var{bfdname} | --target=@var{bfdname} ]
1161 [ -C | --demangle ]
1162 [ -d | --disassemble ]
1163 [ -D | --disassemble-all ]
1164 [ -z | --disassemble-zeroes ]
252b5132
RH
1165 [ -EB | -EL | --endian=@{big | little @} ]
1166 [ -f | --file-headers ]
1dada9c5
NC
1167 [ -g | --debugging ]
1168 [ -h | --section-headers | --headers ]
1169 [ -i | --info ]
252b5132 1170 [ -j @var{section} | --section=@var{section} ]
1dada9c5
NC
1171 [ -l | --line-numbers ]
1172 [ -S | --source ]
252b5132 1173 [ -m @var{machine} | --architecture=@var{machine} ]
dd92f639 1174 [ -M @var{options} | --disassembler-options=@var{options}]
252b5132 1175 [ -p | --private-headers ]
1dada9c5
NC
1176 [ -r | --reloc ]
1177 [ -R | --dynamic-reloc ]
1178 [ -s | --full-contents ]
1179 [ -G | --stabs ]
1180 [ -t | --syms ]
1181 [ -T | --dynamic-syms ]
1182 [ -x | --all-headers ]
1183 [ -w | --wide ]
1184 [ --start-address=@var{address} ]
252b5132 1185 [ --stop-address=@var{address} ]
1dada9c5
NC
1186 [ --prefix-addresses]
1187 [ --[no-]show-raw-insn ]
252b5132 1188 [ --adjust-vma=@var{offset} ]
1dada9c5
NC
1189 [ -V | --version ]
1190 [ -H | --help ]
252b5132
RH
1191 @var{objfile}@dots{}
1192@end smallexample
1193
1194@code{objdump} displays information about one or more object files.
1195The options control what particular information to display. This
1196information is mostly useful to programmers who are working on the
1197compilation tools, as opposed to programmers who just want their
1198program to compile and work.
1199
1200@var{objfile}@dots{} are the object files to be examined. When you
1201specify archives, @code{objdump} shows information on each of the member
1202object files.
1203
1204The long and short forms of options, shown here as alternatives, are
1dada9c5
NC
1205equivalent. At least one option from the list
1206@samp{-a,-d,-D,-f,-g,-G,-h,-H,-p,-r,-R,-S,-t,-T,-V,-x} must be given.
252b5132
RH
1207
1208@table @code
1209@item -a
1210@itemx --archive-header
1211@cindex archive headers
1212If any of the @var{objfile} files are archives, display the archive
1213header information (in a format similar to @samp{ls -l}). Besides the
1214information you could list with @samp{ar tv}, @samp{objdump -a} shows
1215the object file format of each archive member.
1216
1217@item --adjust-vma=@var{offset}
1218@cindex section addresses in objdump
1219@cindex VMA in objdump
1220When dumping information, first add @var{offset} to all the section
1221addresses. This is useful if the section addresses do not correspond to
1222the symbol table, which can happen when putting sections at particular
1223addresses when using a format which can not represent section addresses,
1224such as a.out.
1225
1226@item -b @var{bfdname}
1227@itemx --target=@var{bfdname}
1228@cindex object code format
1229Specify that the object-code format for the object files is
1230@var{bfdname}. This option may not be necessary; @var{objdump} can
1231automatically recognize many formats.
1232
1233For example,
1234@example
1235objdump -b oasys -m vax -h fu.o
1236@end example
1237@noindent
1238displays summary information from the section headers (@samp{-h}) of
1239@file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1240file in the format produced by Oasys compilers. You can list the
1241formats available with the @samp{-i} option.
1242@xref{Target Selection}, for more information.
1243
1244@item -C
1245@itemx --demangle
1246@cindex demangling in objdump
1247Decode (@dfn{demangle}) low-level symbol names into user-level names.
1248Besides removing any initial underscore prepended by the system, this
1249makes C++ function names readable. @xref{c++filt}, for more information
1250on demangling.
1251
1dada9c5 1252@item -G
252b5132
RH
1253@item --debugging
1254Display debugging information. This attempts to parse debugging
1255information stored in the file and print it out using a C like syntax.
1256Only certain types of debugging information have been implemented.
1257
1258@item -d
1259@itemx --disassemble
1260@cindex disassembling object code
1261@cindex machine instructions
1262Display the assembler mnemonics for the machine instructions from
1263@var{objfile}. This option only disassembles those sections which are
1264expected to contain instructions.
1265
1266@item -D
1267@itemx --disassemble-all
1268Like @samp{-d}, but disassemble the contents of all sections, not just
1269those expected to contain instructions.
1270
1271@item --prefix-addresses
1272When disassembling, print the complete address on each line. This is
1273the older disassembly format.
1274
1275@item --disassemble-zeroes
1276Normally the disassembly output will skip blocks of zeroes. This
1277option directs the disassembler to disassemble those blocks, just like
1278any other data.
1279
1280@item -EB
1281@itemx -EL
1282@itemx --endian=@{big|little@}
1283@cindex endianness
1284@cindex disassembly endianness
1285Specify the endianness of the object files. This only affects
1286disassembly. This can be useful when disassembling a file format which
1287does not describe endianness information, such as S-records.
1288
1289@item -f
1290@itemx --file-header
1291@cindex object file header
1292Display summary information from the overall header of
1293each of the @var{objfile} files.
1294
1295@item -h
1296@itemx --section-header
1297@itemx --header
1298@cindex section headers
1299Display summary information from the section headers of the
1300object file.
1301
1302File segments may be relocated to nonstandard addresses, for example by
1303using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1304@code{ld}. However, some object file formats, such as a.out, do not
1305store the starting address of the file segments. In those situations,
1306although @code{ld} relocates the sections correctly, using @samp{objdump
1307-h} to list the file section headers cannot show the correct addresses.
1308Instead, it shows the usual addresses, which are implicit for the
1309target.
1310
1311@item --help
1312Print a summary of the options to @code{objdump} and exit.
1313
1314@item -i
1315@itemx --info
1316@cindex architectures available
1317@cindex object formats available
1318Display a list showing all architectures and object formats available
1319for specification with @samp{-b} or @samp{-m}.
1320
1321@item -j @var{name}
1322@itemx --section=@var{name}
1323@cindex section information
1324Display information only for section @var{name}.
1325
1326@item -l
1327@itemx --line-numbers
1328@cindex source filenames for object files
1329Label the display (using debugging information) with the filename and
1330source line numbers corresponding to the object code or relocs shown.
1331Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1332
1333@item -m @var{machine}
1334@itemx --architecture=@var{machine}
1335@cindex architecture
1336@cindex disassembly architecture
1337Specify the architecture to use when disassembling object files. This
1338can be useful when disassembling object files which do not describe
1339architecture information, such as S-records. You can list the available
1340architectures with the @samp{-i} option.
1341
dd92f639
NC
1342@item -M @var{options}
1343@itemx --disassembler-options=@var{options}
1344Pass target specific information to the disassembler. Only supported on
1345some targets.
1346
1347If the target is an ARM architecture then this switch can be used to
1348select which register name set is used during disassembler. Specifying
58efb6c0
NC
1349@samp{-M reg-name-std} (the default) will select the register names as
1350used in ARM's instruction set documentation, but with register 13 called
1351'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1352@samp{-M reg-names-apcs} will select the name set used by the ARM
1353Procedure Call Standard, whilst specifying @samp{-M reg-names-raw} will
1354just use @samp{r} followed by the register number.
1355
1356There are also two variants on the APCS register naming scheme enabled
1357by @samp{-M reg-names-atpcs} and @samp{-M reg-names-atpcs-special} which
1358use the ARM/Thumb Procedure Call Standard naming conventions. (Eiuther
1359with the normal register name sor the special register names).
dd92f639 1360
8f915f68
NC
1361This option can also be used for ARM architectures to force the
1362disassembler to interpret all instructions as THUMB instructions by
1363using the switch @samp{--disassembler-options=force-thumb}. This can be
1364useful when attempting to disassemble thumb code produced by other
1365compilers.
1366
252b5132
RH
1367@item -p
1368@itemx --private-headers
1369Print information that is specific to the object file format. The exact
1370information printed depends upon the object file format. For some
1371object file formats, no additional information is printed.
1372
1373@item -r
1374@itemx --reloc
1375@cindex relocation entries, in object file
1376Print the relocation entries of the file. If used with @samp{-d} or
1377@samp{-D}, the relocations are printed interspersed with the
1378disassembly.
1379
1380@item -R
1381@itemx --dynamic-reloc
1382@cindex dynamic relocation entries, in object file
1383Print the dynamic relocation entries of the file. This is only
1384meaningful for dynamic objects, such as certain types of shared
1385libraries.
1386
1387@item -s
1388@itemx --full-contents
1389@cindex sections, full contents
1390@cindex object file sections
1391Display the full contents of any sections requested.
1392
1393@item -S
1394@itemx --source
1395@cindex source disassembly
1396@cindex disassembly, with source
1397Display source code intermixed with disassembly, if possible. Implies
1398@samp{-d}.
1399
1400@item --show-raw-insn
1401When disassembling instructions, print the instruction in hex as well as
1402in symbolic form. This is the default except when
1403@code{--prefix-addresses} is used.
1404
1405@item --no-show-raw-insn
1406When disassembling instructions, do not print the instruction bytes.
1407This is the default when @code{--prefix-addresses} is used.
1408
1dada9c5 1409@item -G
252b5132
RH
1410@item --stabs
1411@cindex stab
1412@cindex .stab
1413@cindex debug symbols
1414@cindex ELF object file format
1415Display the full contents of any sections requested. Display the
1416contents of the .stab and .stab.index and .stab.excl sections from an
1417ELF file. This is only useful on systems (such as Solaris 2.0) in which
1418@code{.stab} debugging symbol-table entries are carried in an ELF
1419section. In most other file formats, debugging symbol-table entries are
1420interleaved with linkage symbols, and are visible in the @samp{--syms}
1421output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1422Overview,stabs.info, The ``stabs'' debug format}.
1423
1424@item --start-address=@var{address}
1425@cindex start-address
1426Start displaying data at the specified address. This affects the output
1427of the @code{-d}, @code{-r} and @code{-s} options.
1428
1429@item --stop-address=@var{address}
1430@cindex stop-address
1431Stop displaying data at the specified address. This affects the output
1432of the @code{-d}, @code{-r} and @code{-s} options.
1433
1434@item -t
1435@itemx --syms
1436@cindex symbol table entries, printing
1437Print the symbol table entries of the file.
1438This is similar to the information provided by the @samp{nm} program.
1439
1440@item -T
1441@itemx --dynamic-syms
1442@cindex dynamic symbol table entries, printing
1443Print the dynamic symbol table entries of the file. This is only
1444meaningful for dynamic objects, such as certain types of shared
1445libraries. This is similar to the information provided by the @samp{nm}
1446program when given the @samp{-D} (@samp{--dynamic}) option.
1447
1448@item --version
1449Print the version number of @code{objdump} and exit.
1450
1451@item -x
1452@itemx --all-header
1453@cindex all header information, object file
1454@cindex header information, all
1455Display all available header information, including the symbol table and
1456relocation entries. Using @samp{-x} is equivalent to specifying all of
1457@samp{-a -f -h -r -t}.
1458
1459@item -w
1460@itemx --wide
1461@cindex wide output, printing
1462Format some lines for output devices that have more than 80 columns.
1463@end table
1464
1465@node ranlib
1466@chapter ranlib
1467
1468@kindex ranlib
1469@cindex archive contents
1470@cindex symbol index
1471
1472@smallexample
1473ranlib [-vV] @var{archive}
1474@end smallexample
1475
1476@code{ranlib} generates an index to the contents of an archive and
1477stores it in the archive. The index lists each symbol defined by a
1478member of an archive that is a relocatable object file.
1479
1480You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1481
1482An archive with such an index speeds up linking to the library and
1483allows routines in the library to call each other without regard to
1484their placement in the archive.
1485
1486The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1487@code{ranlib} is completely equivalent to executing @samp{ar -s}.
1488@xref{ar}.
1489
1490@table @code
1491@item -v
1492@itemx -V
f20a759a 1493@itemx --version
252b5132
RH
1494Show the version number of @code{ranlib}.
1495@end table
1496
1497@node size
1498@chapter size
1499
1500@kindex size
1501@cindex section sizes
1502
1503@smallexample
1504size [ -A | -B | --format=@var{compatibility} ]
1505 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1506 [ --target=@var{bfdname} ] [ -V | --version ]
1507 [ @var{objfile}@dots{} ]
1508@end smallexample
1509
1510The @sc{gnu} @code{size} utility lists the section sizes---and the total
1511size---for each of the object or archive files @var{objfile} in its
1512argument list. By default, one line of output is generated for each
1513object file or each module in an archive.
1514
1515@var{objfile}@dots{} are the object files to be examined.
1516If none are specified, the file @code{a.out} will be used.
1517
1518The command line options have the following meanings:
1519
1520@table @code
1521@item -A
1522@itemx -B
1523@itemx --format=@var{compatibility}
1524@cindex @code{size} display format
1525Using one of these options, you can choose whether the output from @sc{gnu}
1526@code{size} resembles output from System V @code{size} (using @samp{-A},
1527or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1528@samp{--format=berkeley}). The default is the one-line format similar to
1529Berkeley's.
1530@c Bonus for doc-source readers: you can also say --format=strange (or
1531@c anything else that starts with 's') for sysv, and --format=boring (or
1532@c anything else that starts with 'b') for Berkeley.
1533
1534Here is an example of the Berkeley (default) format of output from
1535@code{size}:
1536@smallexample
f20a759a 1537$ size --format=Berkeley ranlib size
252b5132
RH
1538text data bss dec hex filename
1539294880 81920 11592 388392 5ed28 ranlib
1540294880 81920 11888 388688 5ee50 size
1541@end smallexample
1542
1543@noindent
1544This is the same data, but displayed closer to System V conventions:
1545
1546@smallexample
f20a759a 1547$ size --format=SysV ranlib size
252b5132
RH
1548ranlib :
1549section size addr
1550.text 294880 8192
1551.data 81920 303104
1552.bss 11592 385024
1553Total 388392
1554
1555
1556size :
1557section size addr
1558.text 294880 8192
1559.data 81920 303104
1560.bss 11888 385024
1561Total 388688
1562@end smallexample
1563
1564@item --help
1565Show a summary of acceptable arguments and options.
1566
1567@item -d
1568@itemx -o
1569@itemx -x
1570@itemx --radix=@var{number}
1571@cindex @code{size} number format
1572@cindex radix for section sizes
1573Using one of these options, you can control whether the size of each
1574section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1575(@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1576@samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1577values (8, 10, 16) are supported. The total size is always given in two
1578radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1579octal and hexadecimal if you're using @samp{-o}.
1580
1581@item --target=@var{bfdname}
1582@cindex object code format
1583Specify that the object-code format for @var{objfile} is
1584@var{bfdname}. This option may not be necessary; @code{size} can
1585automatically recognize many formats.
1586@xref{Target Selection}, for more information.
1587
1588@item -V
1589@itemx --version
1590Display the version number of @code{size}.
1591@end table
1592
1593@node strings
1594@chapter strings
1595@kindex strings
1596@cindex listings strings
1597@cindex printing strings
1598@cindex strings, printing
1599
1600@smallexample
1601strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1602 [--all] [--print-file-name] [--bytes=@var{min-len}]
1603 [--radix=@var{radix}] [--target=@var{bfdname}]
1604 [--help] [--version] @var{file}@dots{}
1605@end smallexample
1606
1607For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1608character sequences that are at least 4 characters long (or the number
1609given with the options below) and are followed by an unprintable
1610character. By default, it only prints the strings from the initialized
1611and loaded sections of object files; for other types of files, it prints
1612the strings from the whole file.
1613
1614@code{strings} is mainly useful for determining the contents of non-text
1615files.
1616
1617@table @code
1618@item -a
1619@itemx --all
1620@itemx -
1621Do not scan only the initialized and loaded sections of object files;
1622scan the whole files.
1623
1624@item -f
1625@itemx --print-file-name
1626Print the name of the file before each string.
1627
1628@item --help
1629Print a summary of the program usage on the standard output and exit.
1630
1631@item -@var{min-len}
1632@itemx -n @var{min-len}
1633@itemx --bytes=@var{min-len}
1634Print sequences of characters that are at least @var{min-len} characters
1635long, instead of the default 4.
1636
1637@item -o
1638Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1639act like @samp{-t d} instead. Since we can not be compatible with both
1640ways, we simply chose one.
1641
1642@item -t @var{radix}
1643@itemx --radix=@var{radix}
1644Print the offset within the file before each string. The single
1645character argument specifies the radix of the offset---@samp{o} for
1646octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1647
1648@item --target=@var{bfdname}
1649@cindex object code format
1650Specify an object code format other than your system's default format.
1651@xref{Target Selection}, for more information.
1652
1653@item -v
1654@itemx --version
1655Print the program version number on the standard output and exit.
1656@end table
1657
1658@node strip
1659@chapter strip
1660
1661@kindex strip
1662@cindex removing symbols
1663@cindex discarding symbols
1664@cindex symbols, discarding
1665
1666@smallexample
1667strip [ -F @var{bfdname} | --target=@var{bfdname} ]
1668 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1669 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1670 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1671 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1672 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1673 [ -x | --discard-all ] [ -X | --discard-locals ]
1674 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1675 [ -o @var{file} ] [ -p | --preserve-dates ]
1676 [ -v | --verbose ] [ -V | --version ] [ --help ]
1677 @var{objfile}@dots{}
1678@end smallexample
1679
1680@sc{gnu} @code{strip} discards all symbols from object files
1681@var{objfile}. The list of object files may include archives.
1682At least one object file must be given.
1683
1684@code{strip} modifies the files named in its argument,
1685rather than writing modified copies under different names.
1686
1687@table @code
1688@item -F @var{bfdname}
1689@itemx --target=@var{bfdname}
1690Treat the original @var{objfile} as a file with the object
1691code format @var{bfdname}, and rewrite it in the same format.
1692@xref{Target Selection}, for more information.
1693
1694@item --help
1695Show a summary of the options to @code{strip} and exit.
1696
1697@item -I @var{bfdname}
1698@itemx --input-target=@var{bfdname}
1699Treat the original @var{objfile} as a file with the object
1700code format @var{bfdname}.
1701@xref{Target Selection}, for more information.
1702
1703@item -O @var{bfdname}
1704@itemx --output-target=@var{bfdname}
1705Replace @var{objfile} with a file in the output format @var{bfdname}.
1706@xref{Target Selection}, for more information.
1707
1708@item -R @var{sectionname}
1709@itemx --remove-section=@var{sectionname}
1710Remove any section named @var{sectionname} from the output file. This
1711option may be given more than once. Note that using this option
1712inappropriately may make the output file unusable.
1713
1714@item -s
1715@itemx --strip-all
1716Remove all symbols.
1717
1718@item -g
1719@itemx -S
1720@itemx --strip-debug
1721Remove debugging symbols only.
1722
1723@item --strip-unneeded
1724Remove all symbols that are not needed for relocation processing.
1725
1726@item -K @var{symbolname}
1727@itemx --keep-symbol=@var{symbolname}
1728Keep only symbol @var{symbolname} from the source file. This option may
1729be given more than once.
1730
1731@item -N @var{symbolname}
1732@itemx --strip-symbol=@var{symbolname}
1733Remove symbol @var{symbolname} from the source file. This option may be
1734given more than once, and may be combined with strip options other than
1735@code{-K}.
1736
1737@item -o @var{file}
1738Put the stripped output in @var{file}, rather than replacing the
1739existing file. When this argument is used, only one @var{objfile}
1740argument may be specified.
1741
1742@item -p
1743@itemx --preserve-dates
1744Preserve the access and modification dates of the file.
1745
1746@item -x
1747@itemx --discard-all
1748Remove non-global symbols.
1749
1750@item -X
1751@itemx --discard-locals
1752Remove compiler-generated local symbols.
1753(These usually start with @samp{L} or @samp{.}.)
1754
1755@item -V
1756@itemx --version
1757Show the version number for @code{strip}.
1758
1759@item -v
1760@itemx --verbose
1761Verbose output: list all object files modified. In the case of
1762archives, @samp{strip -v} lists all members of the archive.
1763@end table
1764
9d51cc66 1765@node c++filt, addr2line, strip, Top
252b5132
RH
1766@chapter c++filt
1767
1768@kindex c++filt
1769@cindex demangling C++ symbols
1770
1771@smallexample
1772c++filt [ -_ | --strip-underscores ]
1773 [ -j | --java ]
1774 [ -n | --no-strip-underscores ]
1775 [ -s @var{format} | --format=@var{format} ]
1776 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1777@end smallexample
1778
9d51cc66 1779@kindex cxxfilt
252b5132
RH
1780The C++ and Java languages provides function overloading, which means
1781that you can write many functions with the same name (providing each
1782takes parameters of different types). All C++ and Java function names
1783are encoded into a low-level assembly label (this process is known as
9d51cc66
ILT
1784@dfn{mangling}). The @code{c++filt}
1785@footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
1786MS-DOS this program is named @code{cxxfilt}.}
1787program does the inverse mapping: it decodes (@dfn{demangles}) low-level
1788names into user-level names so that the linker can keep these overloaded
1789functions from clashing.
252b5132
RH
1790
1791Every alphanumeric word (consisting of letters, digits, underscores,
1792dollars, or periods) seen in the input is a potential label. If the
1793label decodes into a C++ name, the C++ name replaces the low-level
1794name in the output.
1795
1796You can use @code{c++filt} to decipher individual symbols:
1797
1798@example
1799c++filt @var{symbol}
1800@end example
1801
1802If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1803names from the standard input and writes the demangled names to the
1804standard output. All results are printed on the standard output.
1805
1806@table @code
1807@item -_
1808@itemx --strip-underscores
1809On some systems, both the C and C++ compilers put an underscore in front
1810of every name. For example, the C name @code{foo} gets the low-level
1811name @code{_foo}. This option removes the initial underscore. Whether
1812@code{c++filt} removes the underscore by default is target dependent.
1813
1814@item -j
1815@itemx --java
1816Prints demangled names using Java syntax. The default is to use C++
1817syntax.
1818
1819@item -n
1820@itemx --no-strip-underscores
1821Do not remove the initial underscore.
1822
1823@item -s @var{format}
1824@itemx --format=@var{format}
1825@sc{gnu} @code{nm} can decode three different methods of mangling, used by
1826different C++ compilers. The argument to this option selects which
1827method it uses:
1828
1829@table @code
1830@item gnu
1831the one used by the @sc{gnu} compiler (the default method)
1832@item lucid
1833the one used by the Lucid compiler
1834@item arm
1835the one specified by the C++ Annotated Reference Manual
1836@item hp
1837the one used by the HP compiler
1838@item edg
1839the one used by the EDG compiler
1840@end table
1841
1842@item --help
1843Print a summary of the options to @code{c++filt} and exit.
1844
1845@item --version
1846Print the version number of @code{c++filt} and exit.
1847@end table
1848
1849@quotation
1850@emph{Warning:} @code{c++filt} is a new utility, and the details of its
1851user interface are subject to change in future releases. In particular,
1852a command-line option may be required in the the future to decode a name
1853passed as an argument on the command line; in other words,
1854
1855@example
1856c++filt @var{symbol}
1857@end example
1858
1859@noindent
1860may in a future release become
1861
1862@example
1863c++filt @var{option} @var{symbol}
1864@end example
1865@end quotation
1866
1867@node addr2line
1868@chapter addr2line
1869
1870@kindex addr2line
1871@cindex address to file name and line number
1872
1873@smallexample
1874addr2line [ -b @var{bfdname} | --target=@var{bfdname} ]
1875 [ -C | --demangle ]
1876 [ -e @var{filename} | --exe=@var{filename} ]
1877 [ -f | --functions ] [ -s | --basename ]
1878 [ -H | --help ] [ -V | --version ]
1879 [ addr addr ... ]
1880@end smallexample
1881
1882@code{addr2line} translates program addresses into file names and line
1883numbers. Given an address and an executable, it uses the debugging
1884information in the executable to figure out which file name and line
1885number are associated with a given address.
1886
1887The executable to use is specified with the @code{-e} option. The
f20a759a 1888default is the file @file{a.out}.
252b5132
RH
1889
1890@code{addr2line} has two modes of operation.
1891
1892In the first, hexadecimal addresses are specified on the command line,
1893and @code{addr2line} displays the file name and line number for each
1894address.
1895
1896In the second, @code{addr2line} reads hexadecimal addresses from
1897standard input, and prints the file name and line number for each
1898address on standard output. In this mode, @code{addr2line} may be used
1899in a pipe to convert dynamically chosen addresses.
1900
1901The format of the output is @samp{FILENAME:LINENO}. The file name and
1902line number for each address is printed on a separate line. If the
1903@code{-f} option is used, then each @samp{FILENAME:LINENO} line is
1904preceded by a @samp{FUNCTIONNAME} line which is the name of the function
1905containing the address.
1906
1907If the file name or function name can not be determined,
1908@code{addr2line} will print two question marks in their place. If the
1909line number can not be determined, @code{addr2line} will print 0.
1910
1911The long and short forms of options, shown here as alternatives, are
1912equivalent.
1913
1914@table @code
1915@item -b @var{bfdname}
1916@itemx --target=@var{bfdname}
1917@cindex object code format
1918Specify that the object-code format for the object files is
1919@var{bfdname}.
1920
1921@item -C
1922@itemx --demangle
1923@cindex demangling in objdump
1924Decode (@dfn{demangle}) low-level symbol names into user-level names.
1925Besides removing any initial underscore prepended by the system, this
1926makes C++ function names readable. @xref{c++filt}, for more information
1927on demangling.
1928
1929@item -e @var{filename}
1930@itemx --exe=@var{filename}
1931Specify the name of the executable for which addresses should be
1932translated. The default file is @file{a.out}.
1933
1934@item -f
1935@itemx --functions
1936Display function names as well as file and line number information.
1937
1938@item -s
1939@itemx --basenames
1940Display only the base of each file name.
1941@end table
1942
1943@node nlmconv
1944@chapter nlmconv
1945
1946@code{nlmconv} converts a relocatable object file into a NetWare
1947Loadable Module.
1948
1949@ignore
1950@code{nlmconv} currently works with @samp{i386} object
1951files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1952object files in @sc{elf}, or @code{a.out} format@footnote{
1953@code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1954format in the Binary File Descriptor library. It has only been tested
1955with the above formats.}.
1956@end ignore
1957
1958@quotation
1959@emph{Warning:} @code{nlmconv} is not always built as part of the binary
1960utilities, since it is only useful for NLM targets.
1961@end quotation
1962
1963@smallexample
1964nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1965 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1966 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1967 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1968 [ -h | --help ] [ -V | --version ]
1969 @var{infile} @var{outfile}
1970@end smallexample
1971
1972@code{nlmconv} converts the relocatable @samp{i386} object file
1973@var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1974reading @var{headerfile} for NLM header information. For instructions
1975on writing the NLM command file language used in header files, see the
1976@samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1977Development and Tools Overview}, which is part of the NLM Software
1978Developer's Kit (``NLM SDK''), available from Novell, Inc.
1979@code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
1980@var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
1981more information.
1982
1983@code{nlmconv} can perform a link step. In other words, you can list
1984more than one object file for input if you list them in the definitions
1985file (rather than simply specifying one input file on the command line).
1986In this case, @code{nlmconv} calls the linker for you.
1987
1988@table @code
1989@item -I @var{bfdname}
1990@itemx --input-target=@var{bfdname}
1991Object format of the input file. @code{nlmconv} can usually determine
1992the format of a given file (so no default is necessary).
1993@xref{Target Selection}, for more information.
1994
1995@item -O @var{bfdname}
1996@itemx --output-target=@var{bfdname}
1997Object format of the output file. @code{nlmconv} infers the output
1998format based on the input format, e.g. for a @samp{i386} input file the
1999output format is @samp{nlm32-i386}.
2000@xref{Target Selection}, for more information.
2001
2002@item -T @var{headerfile}
2003@itemx --header-file=@var{headerfile}
2004Reads @var{headerfile} for NLM header information. For instructions on
2005writing the NLM command file language used in header files, see@ see the
2006@samp{linkers} section, of the @cite{NLM Development and Tools
2007Overview}, which is part of the NLM Software Developer's Kit, available
2008from Novell, Inc.
2009
2010@item -d
2011@itemx --debug
2012Displays (on standard error) the linker command line used by @code{nlmconv}.
2013
2014@item -l @var{linker}
2015@itemx --linker=@var{linker}
2016Use @var{linker} for any linking. @var{linker} can be an absolute or a
2017relative pathname.
2018
2019@item -h
2020@itemx --help
2021Prints a usage summary.
2022
2023@item -V
2024@itemx --version
2025Prints the version number for @code{nlmconv}.
2026@end table
2027
2028@node windres
2029@chapter windres
2030
2031@code{windres} may be used to manipulate Windows resources.
2032
2033@quotation
2034@emph{Warning:} @code{windres} is not always built as part of the binary
2035utilities, since it is only useful for Windows targets.
2036@end quotation
2037
2038@smallexample
2039windres [options] [input-file] [output-file]
2040@end smallexample
2041
2042@code{windres} reads resources from an input file and copies them into
2043an output file. Either file may be in one of three formats:
2044
2045@table @code
2046@item rc
2047A text format read by the Resource Compiler.
2048
2049@item res
2050A binary format generated by the Resource Compiler.
2051
2052@item coff
2053A COFF object or executable.
2054@end table
2055
2056The exact description of these different formats is available in
2057documentation from Microsoft.
2058
2059When @code{windres} converts from the @code{rc} format to the @code{res}
2060format, it is acting like the Windows Resource Compiler. When
2061@code{windres} converts from the @code{res} format to the @code{coff}
2062format, it is acting like the Windows @code{CVTRES} program.
2063
2064When @code{windres} generates an @code{rc} file, the output is similar
2065but not identical to the format expected for the input. When an input
2066@code{rc} file refers to an external filename, an output @code{rc} file
2067will instead include the file contents.
2068
2069If the input or output format is not specified, @code{windres} will
2070guess based on the file name, or, for the input file, the file contents.
2071A file with an extension of @file{.rc} will be treated as an @code{rc}
2072file, a file with an extension of @file{.res} will be treated as a
2073@code{res} file, and a file with an extension of @file{.o} or
2074@file{.exe} will be treated as a @code{coff} file.
2075
2076If no output file is specified, @code{windres} will print the resources
2077in @code{rc} format to standard output.
2078
2079The normal use is for you to write an @code{rc} file, use @code{windres}
2080to convert it to a COFF object file, and then link the COFF file into
2081your application. This will make the resources described in the
2082@code{rc} file available to Windows.
2083
2084@table @code
2085@item -i @var{filename}
2086@itemx --input @var{filename}
2087The name of the input file. If this option is not used, then
2088@code{windres} will use the first non-option argument as the input file
2089name. If there are no non-option arguments, then @code{windres} will
2090read from standard input. @code{windres} can not read a COFF file from
2091standard input.
2092
2093@item -o @var{filename}
2094@itemx --output @var{filename}
2095The name of the output file. If this option is not used, then
2096@code{windres} will use the first non-option argument, after any used
2097for the input file name, as the output file name. If there is no
2098non-option argument, then @code{windres} will write to standard output.
2099@code{windres} can not write a COFF file to standard output.
2100
2101@item -I @var{format}
2102@itemx --input-format @var{format}
2103The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2104@samp{coff}. If no input format is specified, @code{windres} will
2105guess, as described above.
2106
2107@item -O @var{format}
2108@itemx --output-format @var{format}
2109The output format to generate. @var{format} may be @samp{res},
2110@samp{rc}, or @samp{coff}. If no output format is specified,
2111@code{windres} will guess, as described above.
2112
2113@item -F @var{target}
2114@itemx --target @var{target}
2115Specify the BFD format to use for a COFF file as input or output. This
2116is a BFD target name; you can use the @code{--help} option to see a list
2117of supported targets. Normally @code{windres} will use the default
2118format, which is the first one listed by the @code{--help} option.
2119@ref{Target Selection}.
2120
2121@item --preprocessor @var{program}
2122When @code{windres} reads an @code{rc} file, it runs it through the C
2123preprocessor first. This option may be used to specify the preprocessor
2124to use, including any leading arguments. The default preprocessor
2125argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2126
2127@item --include-dir @var{directory}
2128Specify an include directory to use when reading an @code{rc} file.
2129@code{windres} will pass this to the preprocessor as an @code{-I}
2130option. @code{windres} will also search this directory when looking for
2131files named in the @code{rc} file.
2132
751d21b5 2133@item -D @var{target}
ad0481cd 2134@itemx --define @var{sym}[=@var{val}]
252b5132
RH
2135Specify a @code{-D} option to pass to the preprocessor when reading an
2136@code{rc} file.
2137
751d21b5
DD
2138@item -v
2139Enable verbose mode. This tells you what the preprocessor is if you
2140didn't specify one.
2141
252b5132
RH
2142@item --language @var{val}
2143Specify the default language to use when reading an @code{rc} file.
2144@var{val} should be a hexadecimal language code. The low eight bits are
2145the language, and the high eight bits are the sublanguage.
2146
5a298d2d
NC
2147@item --use-temp-file
2148Use a temporary file to instead of using popen to read the output of
2149the preprocessor. Use this option if the popen implementation is buggy
2150on the host (eg., certain non-English language versions of Windows 95 and
2151Windows 98 are known to have buggy popen where the output will instead
2152go the console).
2153
2154@item --no-use-temp-file
2155Use popen, not a temporary file, to read the output of the preprocessor.
2156This is the default behaviour.
2157
252b5132
RH
2158@item --help
2159Prints a usage summary.
2160
2161@item --version
2162Prints the version number for @code{windres}.
2163
2164@item --yydebug
2165If @code{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2166this will turn on parser debugging.
2167@end table
2168
2169
2170@node dlltool
2171@chapter Create files needed to build and use DLLs
2172@cindex DLL
2173@kindex dlltool
2174
2175@code{dlltool} may be used to create the files needed to build and use
2176dynamic link libraries (DLLs).
2177
2178@quotation
2179@emph{Warning:} @code{dlltool} is not always built as part of the binary
2180utilities, since it is only useful for those targets which support DLLs.
2181@end quotation
2182
2183@smallexample
2184dlltool [-d|--input-def @var{def-file-name}]
2185 [-b|--base-file @var{base-file-name}]
2186 [-e|--output-exp @var{exports-file-name}]
2187 [-z|--output-def @var{def-file-name}]
2188 [-l|--output-lib @var{library-file-name}]
2189 [--export-all-symbols] [--no-export-all-symbols]
2190 [--exclude-symbols @var{list}]
2191 [--no-default-excludes]
2192 [-S|--as @var{path-to-assembler}] [-f|--as-flags @var{options}]
2193 [-D|--dllname @var{name}] [-m|--machine @var{machine}]
2194 [-a|--add-indirect] [-U|--add-underscore] [-k|--kill-at]
2195 [-A|--add-stdcall-alias]
2196 [-x|--no-idata4] [-c|--no-idata5] [-i|--interwork]
2197 [-n|--nodelete] [-v|--verbose] [-h|--help] [-V|--version]
2198 [object-file @dots{}]
2199@end smallexample
2200
2201@code{dlltool} reads its inputs, which can come from the @samp{-d} and
2202@samp{-b} options as well as object files specified on the command
2203line. It then processes these inputs and if the @samp{-e} option has
2204been specified it creates a exports file. If the @samp{-l} option
2205has been specified it creates a library file and if the @samp{-z} option
2206has been specified it creates a def file. Any or all of the -e, -l
2207and -z options can be present in one invocation of dlltool.
2208
2209When creating a DLL, along with the source for the DLL, it is necessary
2210to have three other files. @code{dlltool} can help with the creation of
2211these files.
2212
2213The first file is a @samp{.def} file which specifies which functions are
2214exported from the DLL, which functions the DLL imports, and so on. This
2215is a text file and can be created by hand, or @code{dlltool} can be used
2216to create it using the @samp{-z} option. In this case @code{dlltool}
2217will scan the object files specified on its command line looking for
2218those functions which have been specially marked as being exported and
2219put entries for them in the .def file it creates.
2220
2221In order to mark a function as being exported from a DLL, it needs to
2222have an @samp{-export:<name_of_function>} entry in the @samp{.drectve}
2223section of the object file. This can be done in C by using the
2224asm() operator:
2225
2226@smallexample
2227 asm (".section .drectve");
2228 asm (".ascii \"-export:my_func\"");
2229
2230 int my_func (void) @{ @dots{} @}
2231@end smallexample
2232
2233The second file needed for DLL creation is an exports file. This file
2234is linked with the object files that make up the body of the DLL and it
2235handles the interface between the DLL and the outside world. This is a
2236binary file and it can be created by giving the @samp{-e} option to
2237@code{dlltool} when it is creating or reading in a .def file.
2238
2239The third file needed for DLL creation is the library file that programs
2240will link with in order to access the functions in the DLL. This file
2241can be created by giving the @samp{-l} option to dlltool when it
2242is creating or reading in a .def file.
2243
2244@code{dlltool} builds the library file by hand, but it builds the
2245exports file by creating temporary files containing assembler statements
2246and then assembling these. The @samp{-S} command line option can be
2247used to specify the path to the assembler that dlltool will use,
2248and the @samp{-f} option can be used to pass specific flags to that
2249assembler. The @samp{-n} can be used to prevent dlltool from deleting
2250these temporary assembler files when it is done, and if @samp{-n} is
2251specified twice then this will prevent dlltool from deleting the
2252temporary object files it used to build the library.
2253
2254Here is an example of creating a DLL from a source file @samp{dll.c} and
2255also creating a program (from an object file called @samp{program.o})
2256that uses that DLL:
2257
2258@smallexample
2259 gcc -c dll.c
2260 dlltool -e exports.o -l dll.lib dll.o
2261 gcc dll.o exports.o -o dll.dll
2262 gcc program.o dll.lib -o program
2263@end smallexample
2264
2265The command line options have the following meanings:
2266
2267@table @code
2268
2269@item -d @var{filename}
2270@itemx --input-def @var{filename}
2271@cindex input .def file
2272Specifies the name of a .def file to be read in and processed.
2273
2274@item -b @var{filename}
2275@itemx --base-file @var{filename}
2276@cindex base files
2277Specifies the name of a base file to be read in and processed. The
2278contents of this file will be added to the relocation section in the
2279exports file generated by dlltool.
2280
2281@item -e @var{filename}
2282@itemx --output-exp @var{filename}
2283Specifies the name of the export file to be created by dlltool.
2284
2285@item -z @var{filename}
2286@itemx --output-def @var{filename}
2287Specifies the name of the .def file to be created by dlltool.
2288
2289@item -l @var{filename}
2290@itemx --output-lib @var{filename}
2291Specifies the name of the library file to be created by dlltool.
2292
2293@item --export-all-symbols
2294Treat all global and weak defined symbols found in the input object
2295files as symbols to be exported. There is a small list of symbols which
2296are not exported by default; see the @code{--no-default-excludes}
2297option. You may add to the list of symbols to not export by using the
2298@code{--exclude-symbols} option.
2299
2300@item --no-export-all-symbols
2301Only export symbols explicitly listed in an input .def file or in
2302@samp{.drectve} sections in the input object files. This is the default
2303behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2304attributes in the source code.
2305
2306@item --exclude-symbols @var{list}
2307Do not export the symbols in @var{list}. This is a list of symbol names
2308separated by comma or colon characters. The symbol names should not
2309contain a leading underscore. This is only meaningful when
2310@code{--export-all-symbols} is used.
2311
2312@item --no-default-excludes
2313When @code{--export-all-symbols} is used, it will by default avoid
2314exporting certain special symbols. The current list of symbols to avoid
2315exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2316@samp{impure_ptr}. You may use the @code{--no-default-excludes} option
2317to go ahead and export these special symbols. This is only meaningful
2318when @code{--export-all-symbols} is used.
2319
2320@item -S @var{path}
2321@itemx --as @var{path}
2322Specifies the path, including the filename, of the assembler to be used
2323to create the exports file.
2324
2325@item -f @var{switches}
2326@itemx --as-flags @var{switches}
2327Specifies any specific command line switches to be passed to the
2328assembler when building the exports file. This option will work even if
2329the @samp{-S} option is not used. This option only takes one argument,
2330and if it occurs more than once on the command line, then later
2331occurrences will override earlier occurrences. So if it is necessary to
2332pass multiple switches to the assembler they should be enclosed in
2333double quotes.
2334
2335@item -D @var{name}
2336@itemx --dll-name @var{name}
2337Specifies the name to be stored in the .def file as the name of the DLL
2338when the @samp{-e} option is used. If this option is not present, then
2339the filename given to the @samp{-e} option will be used as the name of
2340the DLL.
2341
2342@item -m @var{machine}
2343@itemx -machine @var{machine}
2344Specifies the type of machine for which the library file should be
2345built. @code{dlltool} has a built in default type, depending upon how
2346it was created, but this option can be used to override that. This is
2347normally only useful when creating DLLs for an ARM processor, when the
2348contents of the DLL are actually encode using THUMB instructions.
2349
2350@item -a
2351@itemx --add-indirect
2352Specifies that when @code{dlltool} is creating the exports file it
2353should add a section which allows the exported functions to be
2354referenced without using the import library. Whatever the hell that
2355means!
2356
2357@item -U
2358@itemx --add-underscore
2359Specifies that when @code{dlltool} is creating the exports file it
2360should prepend an underscore to the names of the exported functions.
2361
2362@item -k
2363@itemx --kill-at
2364Specifies that when @code{dlltool} is creating the exports file it
2365should not append the string @samp{@@ <number>}. These numbers are
2366called ordinal numbers and they represent another way of accessing the
2367function in a DLL, other than by name.
2368
2369@item -A
2370@itemx --add-stdcall-alias
2371Specifies that when @code{dlltool} is creating the exports file it
2372should add aliases for stdcall symbols without @samp{@@ <number>}
2373in addition to the symbols with @samp{@@ <number>}.
2374
2375@item -x
2376@itemx --no-idata4
2377Specifies that when @code{dlltool} is creating the exports and library
2378files it should omit the .idata4 section. This is for compatibility
2379with certain operating systems.
2380
2381@item -c
2382@itemx --no-idata5
2383Specifies that when @code{dlltool} is creating the exports and library
2384files it should omit the .idata5 section. This is for compatibility
2385with certain operating systems.
2386
2387@item -i
2388@itemx --interwork
2389Specifies that @code{dlltool} should mark the objects in the library
2390file and exports file that it produces as supporting interworking
2391between ARM and THUMB code.
2392
2393@item -n
2394@itemx --nodelete
2395Makes @code{dlltool} preserve the temporary assembler files it used to
2396create the exports file. If this option is repeated then dlltool will
2397also preserve the temporary object files it uses to create the library
2398file.
2399
2400@item -v
2401@itemx --verbose
2402Make dlltool describe what it is doing.
2403
2404@item -h
2405@itemx --help
2406Displays a list of command line options and then exits.
2407
2408@item -V
2409@itemx --version
2410Displays dlltool's version number and then exits.
2411
2412@end table
2413
2414@node readelf
2415@chapter readelf
2416
2417@cindex ELF file information
2418@kindex readelf
2419
2420@smallexample
2421readelf [ -a | --all ]
2422 [ -h | --file-header]
2423 [ -l | --program-headers | --segments]
2424 [ -S | --section-headers | --sections]
2425 [ -e | --headers]
2426 [ -s | --syms | --symbols]
779fe533 2427 [ -n | --notes]
252b5132
RH
2428 [ -r | --relocs]
2429 [ -d | --dynamic]
2430 [ -V | --version-info]
2431 [ -D | --use-dynamic]
2432 [ -x <number> | --hex-dump=<number>]
2433 [ -w[liapr] | --debug-dump[=info,=line,=abbrev,=pubnames,=ranges]]
2434 [ --histogram]
2435 [ -v | --version]
2436 [ -H | --help]
2437 @var{elffile}@dots{}
2438@end smallexample
2439
2440@code{readelf} displays information about one or more ELF format object
2441files. The options control what particular information to display.
2442
2443@var{elffile}@dots{} are the object files to be examined. At the
2444moment, @code{readelf} does not support examining archives, nor does it
2445support examing 64 bit ELF files.
2446
2447The long and short forms of options, shown here as alternatives, are
2448equivalent. At least one option besides @samp{-v} or @samp{-H} must be
2449given.
2450
2451@table @code
2452@item -a
2453@itemx --all
2454Equivalent to specifiying @samp{--file-header},
2455@samp{--program-headers}, @samp{--sections}, @samp{--symbols},
779fe533
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2456@samp{--relocs}, @samp{--dynamic}, @samp{--notes} and
2457@samp{--version-info}.
252b5132
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2458
2459@item -h
2460@itemx --file-header
2461@cindex ELF file header information
2462Displays the information contained in the ELF header at the start of the
2463file.
2464
2465@item -l
2466@itemx --program-headers
2467@itemx --segments
2468@cindex ELF program header information
2469@cindex ELF segment information
2470Displays the information contained in the file's segment headers, if it
2471has any.
2472
2473@item -S
2474@itemx --sections
2475@itemx --section-headers
2476@cindex ELF section information
2477Displays the information contained in the file's section headers, if it
2478has any.
2479
2480@item -s
2481@itemx --symbols
2482@itemx --syms
2483@cindex ELF symbol table information
2484Displays the entries in symbol table section of the file, if it has one.
2485
2486@item -e
2487@itemx --headers
2488Display all the headers in the file. Equivalent to @samp{-h -l -S}.
2489
779fe533
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2490@item -n
2491@itemx --notes
2492@cindex ELF core notes
2493Displays the contents of the NOTE segment, if it exists.
2494
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2495@item -r
2496@itemx --relocs
2497@cindex ELF reloc information
2498Displays the contents of the file's relocation section, if it ha one.
2499
2500@item -d
2501@itemx --dynamic
2502@cindex ELF dynamic section information
2503Displays the contents of the file's dynamic section, if it has one.
2504
2505@item -V
2506@itemx --version-info
2507@cindex ELF version sections informations
2508Displays the contents of the version sections in the file, it they
2509exist.
2510
2511@item -D
2512@itemx --use-dynamic
2513When displaying symbols, this option makes @code{readelf} use the
2514symblol table in the file's dynamic section, rather than the one in the
2515symbols section.
2516
2517@item -x <number>
2518@itemx --hex-dump=<number>
2519Displays the contents of the indicated section as a hexadecimal dump.
2520
2521@item -w[liapr]
2522@itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges]
2523Displays the contents of the debug sections in the file, if any are
2524present. If one of the optional letters or words follows the switch
2525then only data found in those specific sections will be dumped.
2526
2527@item --histogram
2528Display a histogram of bucket list lengths when displaying the contents
2529of the symbol tables.
2530
2531@item -v
2532@itemx --version
2533Display the version number of readelf.
2534
2535@item -H
2536@itemx --help
2537Display the command line options understood by @code{readelf}.
2538
2539@end table
2540
2541
2542@node Selecting The Target System
2543@chapter Selecting the target system
2544
2545You can specify three aspects of the target system to the @sc{gnu}
2546binary file utilities, each in several ways:
2547
2548@itemize @bullet
2549@item
2550the target
2551
2552@item
2553the architecture
2554
2555@item
2556the linker emulation (which applies to the linker only)
2557@end itemize
2558
2559In the following summaries, the lists of ways to specify values are in
2560order of decreasing precedence. The ways listed first override those
2561listed later.
2562
2563The commands to list valid values only list the values for which the
2564programs you are running were configured. If they were configured with
2565@samp{--enable-targets=all}, the commands list most of the available
2566values, but a few are left out; not all targets can be configured in at
2567once because some of them can only be configured @dfn{native} (on hosts
2568with the same type as the target system).
2569
2570@menu
2571* Target Selection::
2572* Architecture Selection::
2573* Linker Emulation Selection::
2574@end menu
2575
2576@node Target Selection
2577@section Target Selection
2578
2579A @dfn{target} is an object file format. A given target may be
2580supported for multiple architectures (@pxref{Architecture Selection}).
2581A target selection may also have variations for different operating
2582systems or architectures.
2583
2584The command to list valid target values is @samp{objdump -i}
2585(the first column of output contains the relevant information).
2586
2587Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
2588@samp{a.out-sunos-big}.
2589
2590You can also specify a target using a configuration triplet. This is
f20a759a
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2591the same sort of name that is passed to @file{configure} to specify a
2592target. When you use a configuration triplet as an argument, it must be
2593fully canonicalized. You can see the canonical version of a triplet by
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2594running the shell script @file{config.sub} which is included with the
2595sources.
2596
2597Some sample configuration triplets are: @samp{m68k-hp-bsd},
2598@samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
2599
2600@subheading @code{objdump} Target
2601
2602Ways to specify:
2603
2604@enumerate
2605@item
2606command line option: @samp{-b} or @samp{--target}
2607
2608@item
2609environment variable @code{GNUTARGET}
2610
2611@item
2612deduced from the input file
2613@end enumerate
2614
2615@subheading @code{objcopy} and @code{strip} Input Target
2616
2617Ways to specify:
2618
2619@enumerate
2620@item
2621command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
2622
2623@item
2624environment variable @code{GNUTARGET}
2625
2626@item
2627deduced from the input file
2628@end enumerate
2629
2630@subheading @code{objcopy} and @code{strip} Output Target
2631
2632Ways to specify:
2633
2634@enumerate
2635@item
2636command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
2637
2638@item
2639the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
2640
2641@item
2642environment variable @code{GNUTARGET}
2643
2644@item
2645deduced from the input file
2646@end enumerate
2647
2648@subheading @code{nm}, @code{size}, and @code{strings} Target
2649
2650Ways to specify:
2651
2652@enumerate
2653@item
2654command line option: @samp{--target}
2655
2656@item
2657environment variable @code{GNUTARGET}
2658
2659@item
2660deduced from the input file
2661@end enumerate
2662
2663@subheading Linker Input Target
2664
2665Ways to specify:
2666
2667@enumerate
2668@item
2669command line option: @samp{-b} or @samp{--format}
2670(@pxref{Options,,Options,ld.info,Using LD})
2671
2672@item
2673script command @code{TARGET}
2674(@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2675
2676@item
2677environment variable @code{GNUTARGET}
2678(@pxref{Environment,,Environment,ld.info,Using LD})
2679
2680@item
2681the default target of the selected linker emulation
2682(@pxref{Linker Emulation Selection})
2683@end enumerate
2684
2685@subheading Linker Output Target
2686
2687Ways to specify:
2688
2689@enumerate
2690@item
2691command line option: @samp{-oformat}
2692(@pxref{Options,,Options,ld.info,Using LD})
2693
2694@item
2695script command @code{OUTPUT_FORMAT}
2696(@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2697
2698@item
2699the linker input target (see ``Linker Input Target'' above)
2700@end enumerate
2701
2702@node Architecture Selection
2703@section Architecture selection
2704
2705An @dfn{architecture} is a type of @sc{cpu} on which an object file is
2706to run. Its name may contain a colon, separating the name of the
2707processor family from the name of the particular @sc{cpu}.
2708
2709The command to list valid architecture values is @samp{objdump -i} (the
2710second column contains the relevant information).
2711
2712Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
2713
2714@subheading @code{objdump} Architecture
2715
2716Ways to specify:
2717
2718@enumerate
2719@item
2720command line option: @samp{-m} or @samp{--architecture}
2721
2722@item
2723deduced from the input file
2724@end enumerate
2725
2726@subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
2727
2728Ways to specify:
2729
2730@enumerate
2731@item
2732deduced from the input file
2733@end enumerate
2734
2735@subheading Linker Input Architecture
2736
2737Ways to specify:
2738
2739@enumerate
2740@item
2741deduced from the input file
2742@end enumerate
2743
2744@subheading Linker Output Architecture
2745
2746Ways to specify:
2747
2748@enumerate
2749@item
2750script command @code{OUTPUT_ARCH}
2751(@pxref{Option Commands,,Option Commands,ld.info,Using LD})
2752
2753@item
2754the default architecture from the linker output target
2755(@pxref{Target Selection})
2756@end enumerate
2757
2758@node Linker Emulation Selection
2759@section Linker emulation selection
2760
2761A linker @dfn{emulation} is a ``personality'' of the linker, which gives
2762the linker default values for the other aspects of the target system.
2763In particular, it consists of
2764
2765@itemize @bullet
2766@item
2767the linker script
2768
2769@item
2770the target
2771
2772@item
2773several ``hook'' functions that are run at certain stages of the linking
2774process to do special things that some targets require
2775@end itemize
2776
2777The command to list valid linker emulation values is @samp{ld -V}.
2778
2779Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
2780
2781Ways to specify:
2782
2783@enumerate
2784@item
2785command line option: @samp{-m}
2786(@pxref{Options,,Options,ld.info,Using LD})
2787
2788@item
2789environment variable @code{LDEMULATION}
2790
2791@item
2792compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
2793which comes from @code{EMUL} in @file{config/@var{target}.mt}
2794@end enumerate
2795
2796@node Reporting Bugs
2797@chapter Reporting Bugs
2798@cindex bugs
2799@cindex reporting bugs
2800
2801Your bug reports play an essential role in making the binary utilities
2802reliable.
2803
2804Reporting a bug may help you by bringing a solution to your problem, or
2805it may not. But in any case the principal function of a bug report is
2806to help the entire community by making the next version of the binary
2807utilities work better. Bug reports are your contribution to their
2808maintenance.
2809
2810In order for a bug report to serve its purpose, you must include the
2811information that enables us to fix the bug.
2812
2813@menu
2814* Bug Criteria:: Have you found a bug?
2815* Bug Reporting:: How to report bugs
2816@end menu
2817
2818@node Bug Criteria
2819@section Have you found a bug?
2820@cindex bug criteria
2821
2822If you are not sure whether you have found a bug, here are some guidelines:
2823
2824@itemize @bullet
2825@cindex fatal signal
2826@cindex crash
2827@item
2828If a binary utility gets a fatal signal, for any input whatever, that is
2829a bug. Reliable utilities never crash.
2830
2831@cindex error on valid input
2832@item
2833If a binary utility produces an error message for valid input, that is a
2834bug.
2835
2836@item
2837If you are an experienced user of binary utilities, your suggestions for
2838improvement are welcome in any case.
2839@end itemize
2840
2841@node Bug Reporting
2842@section How to report bugs
2843@cindex bug reports
2844@cindex bugs, reporting
2845
2846A number of companies and individuals offer support for @sc{gnu}
2847products. If you obtained the binary utilities from a support
2848organization, we recommend you contact that organization first.
2849
2850You can find contact information for many support companies and
2851individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2852distribution.
2853
2854In any event, we also recommend that you send bug reports for the binary
2855utilities to @samp{bug-gnu-utils@@gnu.org}.
2856
2857The fundamental principle of reporting bugs usefully is this:
2858@strong{report all the facts}. If you are not sure whether to state a
2859fact or leave it out, state it!
2860
2861Often people omit facts because they think they know what causes the
2862problem and assume that some details do not matter. Thus, you might
2863assume that the name of a file you use in an example does not matter.
2864Well, probably it does not, but one cannot be sure. Perhaps the bug is
2865a stray memory reference which happens to fetch from the location where
2866that pathname is stored in memory; perhaps, if the pathname were
2867different, the contents of that location would fool the utility into
2868doing the right thing despite the bug. Play it safe and give a
2869specific, complete example. That is the easiest thing for you to do,
2870and the most helpful.
2871
2872Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2873it is new to us. Therefore, always write your bug reports on the assumption
2874that the bug has not been reported previously.
2875
2876Sometimes people give a few sketchy facts and ask, ``Does this ring a
2877bell?'' Those bug reports are useless, and we urge everyone to
2878@emph{refuse to respond to them} except to chide the sender to report
2879bugs properly.
2880
2881To enable us to fix the bug, you should include all these things:
2882
2883@itemize @bullet
2884@item
2885The version of the utility. Each utility announces it if you start it
2886with the @samp{--version} argument.
2887
2888Without this, we will not know whether there is any point in looking for
2889the bug in the current version of the binary utilities.
2890
2891@item
2892Any patches you may have applied to the source, including any patches
2893made to the @code{BFD} library.
2894
2895@item
2896The type of machine you are using, and the operating system name and
2897version number.
2898
2899@item
2900What compiler (and its version) was used to compile the utilities---e.g.
2901``@code{gcc-2.7}''.
2902
2903@item
2904The command arguments you gave the utility to observe the bug. To
2905guarantee you will not omit something important, list them all. A copy
2906of the Makefile (or the output from make) is sufficient.
2907
2908If we were to try to guess the arguments, we would probably guess wrong
2909and then we might not encounter the bug.
2910
2911@item
2912A complete input file, or set of input files, that will reproduce the
2913bug. If the utility is reading an object file or files, then it is
2914generally most helpful to send the actual object files, uuencoded if
757acbc5
ILT
2915necessary to get them through the mail system. Note that
2916@samp{bug-gnu-utils@@gnu.org} is a mailing list, so you should avoid
2917sending very large files to it. Making the files available for
2918anonymous FTP is OK.
252b5132
RH
2919
2920If the source files were produced exclusively using @sc{gnu} programs
2921(e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2922may be OK to send the source files rather than the object files. In
2923this case, be sure to say exactly what version of @code{gcc}, or
2924whatever, was used to produce the object files. Also say how
2925@code{gcc}, or whatever, was configured.
2926
2927@item
2928A description of what behavior you observe that you believe is
2929incorrect. For example, ``It gets a fatal signal.''
2930
2931Of course, if the bug is that the utility gets a fatal signal, then we
2932will certainly notice it. But if the bug is incorrect output, we might
2933not notice unless it is glaringly wrong. You might as well not give us
2934a chance to make a mistake.
2935
2936Even if the problem you experience is a fatal signal, you should still
f20a759a 2937say so explicitly. Suppose something strange is going on, such as your
252b5132
RH
2938copy of the utility is out of synch, or you have encountered a bug in
2939the C library on your system. (This has happened!) Your copy might
2940crash and ours would not. If you told us to expect a crash, then when
2941ours fails to crash, we would know that the bug was not happening for
2942us. If you had not told us to expect a crash, then we would not be able
2943to draw any conclusion from our observations.
2944
2945@item
2946If you wish to suggest changes to the source, send us context diffs, as
2947generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2948option. Always send diffs from the old file to the new file. If you
f20a759a
ILT
2949wish to discuss something in the @code{ld} source, refer to it by
2950context, not by line number.
252b5132
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2951
2952The line numbers in our development sources will not match those in your
2953sources. Your line numbers would convey no useful information to us.
2954@end itemize
2955
2956Here are some things that are not necessary:
2957
2958@itemize @bullet
2959@item
2960A description of the envelope of the bug.
2961
2962Often people who encounter a bug spend a lot of time investigating
2963which changes to the input file will make the bug go away and which
2964changes will not affect it.
2965
2966This is often time consuming and not very useful, because the way we
2967will find the bug is by running a single example under the debugger
2968with breakpoints, not by pure deduction from a series of examples.
2969We recommend that you save your time for something else.
2970
2971Of course, if you can find a simpler example to report @emph{instead}
2972of the original one, that is a convenience for us. Errors in the
2973output will be easier to spot, running under the debugger will take
2974less time, and so on.
2975
2976However, simplification is not vital; if you do not want to do this,
2977report the bug anyway and send us the entire test case you used.
2978
2979@item
2980A patch for the bug.
2981
2982A patch for the bug does help us if it is a good one. But do not omit
2983the necessary information, such as the test case, on the assumption that
2984a patch is all we need. We might see problems with your patch and decide
2985to fix the problem another way, or we might not understand it at all.
2986
2987Sometimes with programs as complicated as the binary utilities it is
2988very hard to construct an example that will make the program follow a
2989certain path through the code. If you do not send us the example, we
2990will not be able to construct one, so we will not be able to verify that
2991the bug is fixed.
2992
2993And if we cannot understand what bug you are trying to fix, or why your
2994patch should be an improvement, we will not install it. A test case will
2995help us to understand.
2996
2997@item
2998A guess about what the bug is or what it depends on.
2999
3000Such guesses are usually wrong. Even we cannot guess right about such
3001things without first using the debugger to find the facts.
3002@end itemize
3003
3004@node Index
3005@unnumbered Index
3006
3007@printindex cp
3008
3009@contents
3010@bye