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1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @include config.texi
4
5 @ifinfo
6 @format
7 START-INFO-DIR-ENTRY
8 * Binutils: (binutils). The GNU binary utilities "ar", "objcopy",
9 "objdump", "nm", "nlmconv", "size",
10 "strings", "strip", and "ranlib".
11 END-INFO-DIR-ENTRY
12 @end format
13 @end ifinfo
14
15 @ifinfo
16 Copyright @copyright{} 1991, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
17
18 Permission is granted to make and distribute verbatim copies of
19 this manual provided the copyright notice and this permission notice
20 are preserved on all copies.
21
22 @ignore
23 Permission is granted to process this file through TeX and print the
24 results, provided the printed document carries a copying permission
25 notice identical to this one except for the removal of this paragraph
26 (this paragraph not being relevant to the printed manual).
27
28 @end ignore
29
30 Permission is granted to copy and distribute modified versions of this
31 manual under the conditions for verbatim copying, provided also that
32 the entire resulting derived work is distributed under the terms of a
33 permission notice identical to this one.
34
35 Permission is granted to copy and distribute translations of this manual
36 into another language, under the above conditions for modified versions.
37 @end ifinfo
38
39 @synindex ky cp
40 @c
41 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
42 @c "objdump", "nm", "size", "strings", "strip", and "ranlib".
43 @c
44 @c Copyright (C) 1991, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
45 @c
46 @c This text may be freely distributed under the terms of the GNU
47 @c General Public License.
48 @c
49
50 @setchapternewpage odd
51 @settitle @sc{gnu} Binary Utilities
52 @titlepage
53 @finalout
54 @title The @sc{gnu} Binary Utilities
55 @subtitle Version @value{VERSION}
56 @sp 1
57 @subtitle May 1993
58 @author Roland H. Pesch
59 @author Jeffrey M. Osier
60 @author Cygnus Support
61 @page
62
63 @tex
64 {\parskip=0pt \hfill Cygnus Support\par \hfill
65 \TeX{}info \texinfoversion\par }
66 @end tex
67
68 @vskip 0pt plus 1filll
69 Copyright @copyright{} 1991, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
70
71 Permission is granted to make and distribute verbatim copies of
72 this manual provided the copyright notice and this permission notice
73 are preserved on all copies.
74
75 Permission is granted to copy and distribute modified versions of this
76 manual under the conditions for verbatim copying, provided also that
77 the entire resulting derived work is distributed under the terms of a
78 permission notice identical to this one.
79
80 Permission is granted to copy and distribute translations of this manual
81 into another language, under the above conditions for modified versions.
82 @end titlepage
83
84 @node Top
85 @top Introduction
86
87 @cindex version
88 This brief manual contains preliminary documentation for the @sc{gnu} binary
89 utilities (collectively version @value{VERSION}):
90
91 @iftex
92 @table @code
93 @item ar
94 Create, modify, and extract from archives
95
96 @item nm
97 List symbols from object files
98
99 @item objcopy
100 Copy and translate object files
101
102 @item objdump
103 Display information from object files
104
105 @item ranlib
106 Generate index to archive contents
107
108 @item size
109 List file section sizes and total size
110
111 @item strings
112 List printable strings from files
113
114 @item strip
115 Discard symbols
116
117 @item c++filt
118 Demangle encoded C++ symbols
119
120 @item nlmconv
121 Convert object code into a Netware Loadable Module
122 @end table
123 @end iftex
124
125 @menu
126 * ar:: Create, modify, and extract from archives
127 * nm:: List symbols from object files
128 * objcopy:: Copy and translate object files
129 * objdump:: Display information from object files
130 * ranlib:: Generate index to archive contents
131 * size:: List section sizes and total size
132 * strings:: List printable strings from files
133 * strip:: Discard symbols
134 * c++filt:: Filter to demangle encoded C++ symbols
135 * nlmconv:: Converts object code into an NLM
136 * Selecting The Target System:: How these utilities determine the target.
137 * Reporting Bugs:: Reporting Bugs
138 * Index:: Index
139 @end menu
140
141 @node ar
142 @chapter ar
143
144 @kindex ar
145 @cindex archives
146 @cindex collections of files
147 @smallexample
148 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
149 ar -M [ <mri-script ]
150 @end smallexample
151
152 The @sc{gnu} @code{ar} program creates, modifies, and extracts from
153 archives. An @dfn{archive} is a single file holding a collection of
154 other files in a structure that makes it possible to retrieve
155 the original individual files (called @dfn{members} of the archive).
156
157 The original files' contents, mode (permissions), timestamp, owner, and
158 group are preserved in the archive, and can be restored on
159 extraction.
160
161 @cindex name length
162 @sc{gnu} @code{ar} can maintain archives whose members have names of any
163 length; however, depending on how @code{ar} is configured on your
164 system, a limit on member-name length may be imposed for compatibility
165 with archive formats maintained with other tools. If it exists, the
166 limit is often 15 characters (typical of formats related to a.out) or 16
167 characters (typical of formats related to coff).
168
169 @cindex libraries
170 @code{ar} is considered a binary utility because archives of this sort
171 are most often used as @dfn{libraries} holding commonly needed
172 subroutines.
173
174 @cindex symbol index
175 @code{ar} creates an index to the symbols defined in relocatable
176 object modules in the archive when you specify the modifier @samp{s}.
177 Once created, this index is updated in the archive whenever @code{ar}
178 makes a change to its contents (save for the @samp{q} update operation).
179 An archive with such an index speeds up linking to the library, and
180 allows routines in the library to call each other without regard to
181 their placement in the archive.
182
183 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
184 table. If an archive lacks the table, another form of @code{ar} called
185 @code{ranlib} can be used to add just the table.
186
187 @cindex compatibility, @code{ar}
188 @cindex @code{ar} compatibility
189 @sc{gnu} @code{ar} is designed to be compatible with two different
190 facilities. You can control its activity using command-line options,
191 like the different varieties of @code{ar} on Unix systems; or, if you
192 specify the single command-line option @samp{-M}, you can control it
193 with a script supplied via standard input, like the MRI ``librarian''
194 program.
195
196 @menu
197 * ar cmdline:: Controlling @code{ar} on the command line
198 * ar scripts:: Controlling @code{ar} with a script
199 @end menu
200
201 @page
202 @node ar cmdline
203 @section Controlling @code{ar} on the command line
204
205 @smallexample
206 ar [-]@var{p}[@var{mod} [@var{relpos}]] @var{archive} [@var{member}@dots{}]
207 @end smallexample
208
209 @cindex Unix compatibility, @code{ar}
210 When you use @code{ar} in the Unix style, @code{ar} insists on at least two
211 arguments to execute: one keyletter specifying the @emph{operation}
212 (optionally accompanied by other keyletters specifying
213 @emph{modifiers}), and the archive name to act on.
214
215 Most operations can also accept further @var{member} arguments,
216 specifying particular files to operate on.
217
218 @sc{gnu} @code{ar} allows you to mix the operation code @var{p} and modifier
219 flags @var{mod} in any order, within the first command-line argument.
220
221 If you wish, you may begin the first command-line argument with a
222 dash.
223
224 @cindex operations on archive
225 The @var{p} keyletter specifies what operation to execute; it may be
226 any of the following, but you must specify only one of them:
227
228 @table @code
229 @item d
230 @cindex deleting from archive
231 @emph{Delete} modules from the archive. Specify the names of modules to
232 be deleted as @var{member}@dots{}; the archive is untouched if you
233 specify no files to delete.
234
235 If you specify the @samp{v} modifier, @code{ar} lists each module
236 as it is deleted.
237
238 @item m
239 @cindex moving in archive
240 Use this operation to @emph{move} members in an archive.
241
242 The ordering of members in an archive can make a difference in how
243 programs are linked using the library, if a symbol is defined in more
244 than one member.
245
246 If no modifiers are used with @code{m}, any members you name in the
247 @var{member} arguments are moved to the @emph{end} of the archive;
248 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
249 specified place instead.
250
251 @item p
252 @cindex printing from archive
253 @emph{Print} the specified members of the archive, to the standard
254 output file. If the @samp{v} modifier is specified, show the member
255 name before copying its contents to standard output.
256
257 If you specify no @var{member} arguments, all the files in the archive are
258 printed.
259
260 @item q
261 @cindex quick append to archive
262 @emph{Quick append}; add the files @var{member}@dots{} to the end of
263 @var{archive}, without checking for replacement.
264
265 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
266 operation; new members are always placed at the end of the archive.
267
268 The modifier @samp{v} makes @code{ar} list each file as it is appended.
269
270 Since the point of this operation is speed, the archive's symbol table
271 index is not updated, even if it already existed; you can use @samp{ar s} or
272 @code{ranlib} explicitly to update the symbol table index.
273
274 @item r
275 @cindex replacement in archive
276 Insert the files @var{member}@dots{} into @var{archive} (with
277 @emph{replacement}). This operation differs from @samp{q} in that any
278 previously existing members are deleted if their names match those being
279 added.
280
281 If one of the files named in @var{member}@dots{} does not exist, @code{ar}
282 displays an error message, and leaves undisturbed any existing members
283 of the archive matching that name.
284
285 By default, new members are added at the end of the file; but you may
286 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
287 placement relative to some existing member.
288
289 The modifier @samp{v} used with this operation elicits a line of
290 output for each file inserted, along with one of the letters @samp{a} or
291 @samp{r} to indicate whether the file was appended (no old member
292 deleted) or replaced.
293
294 @item t
295 @cindex contents of archive
296 Display a @emph{table} listing the contents of @var{archive}, or those
297 of the files listed in @var{member}@dots{} that are present in the
298 archive. Normally only the member name is shown; if you also want to
299 see the modes (permissions), timestamp, owner, group, and size, you can
300 request that by also specifying the @samp{v} modifier.
301
302 If you do not specify a @var{member}, all files in the archive
303 are listed.
304
305 @cindex repeated names in archive
306 @cindex name duplication in archive
307 If there is more than one file with the same name (say, @samp{fie}) in
308 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
309 first instance; to see them all, you must ask for a complete
310 listing---in our example, @samp{ar t b.a}.
311 @c WRS only; per Gumby, this is implementation-dependent, and in a more
312 @c recent case in fact works the other way.
313
314 @item x
315 @cindex extract from archive
316 @emph{Extract} members (named @var{member}) from the archive. You can
317 use the @samp{v} modifier with this operation, to request that
318 @code{ar} list each name as it extracts it.
319
320 If you do not specify a @var{member}, all files in the archive
321 are extracted.
322
323 @end table
324
325 A number of modifiers (@var{mod}) may immediately follow the @var{p}
326 keyletter, to specify variations on an operation's behavior:
327
328 @table @code
329 @item a
330 @cindex relative placement in archive
331 Add new files @emph{after} an existing member of the
332 archive. If you use the modifier @samp{a}, the name of an existing archive
333 member must be present as the @var{relpos} argument, before the
334 @var{archive} specification.
335
336 @item b
337 Add new files @emph{before} an existing member of the
338 archive. If you use the modifier @samp{b}, the name of an existing archive
339 member must be present as the @var{relpos} argument, before the
340 @var{archive} specification. (same as @samp{i}).
341
342 @item c
343 @cindex creating archives
344 @emph{Create} the archive. The specified @var{archive} is always
345 created if it did not exist, when you request an update. But a warning is
346 issued unless you specify in advance that you expect to create it, by
347 using this modifier.
348
349 @item f
350 Truncate names in the archive. @sc{gnu} @code{ar} will normally permit file
351 names of any length. This will cause it to create archives which are
352 not compatible with the native @code{ar} program on some systems. If
353 this is a concern, the @samp{f} modifier may be used to truncate file
354 names when putting them in the archive.
355
356 @item i
357 Insert new files @emph{before} an existing member of the
358 archive. If you use the modifier @samp{i}, the name of an existing archive
359 member must be present as the @var{relpos} argument, before the
360 @var{archive} specification. (same as @samp{b}).
361
362 @item l
363 This modifier is accepted but not used.
364 @c whaffor ar l modifier??? presumably compat; with
365 @c what???---doc@@cygnus.com, 25jan91
366
367 @item o
368 @cindex dates in archive
369 Preserve the @emph{original} dates of members when extracting them. If
370 you do not specify this modifier, files extracted from the archive
371 are stamped with the time of extraction.
372
373 @item s
374 @cindex writing archive index
375 Write an object-file index into the archive, or update an existing one,
376 even if no other change is made to the archive. You may use this modifier
377 flag either with any operation, or alone. Running @samp{ar s} on an
378 archive is equivalent to running @samp{ranlib} on it.
379
380 @item u
381 @cindex updating an archive
382 Normally, @samp{ar r}@dots{} inserts all files
383 listed into the archive. If you would like to insert @emph{only} those
384 of the files you list that are newer than existing members of the same
385 names, use this modifier. The @samp{u} modifier is allowed only for the
386 operation @samp{r} (replace). In particular, the combination @samp{qu} is
387 not allowed, since checking the timestamps would lose any speed
388 advantage from the operation @samp{q}.
389
390 @item v
391 This modifier requests the @emph{verbose} version of an operation. Many
392 operations display additional information, such as filenames processed,
393 when the modifier @samp{v} is appended.
394
395 @item V
396 This modifier shows the version number of @code{ar}.
397 @end table
398
399 @node ar scripts
400 @section Controlling @code{ar} with a script
401
402 @smallexample
403 ar -M [ <@var{script} ]
404 @end smallexample
405
406 @cindex MRI compatibility, @code{ar}
407 @cindex scripts, @code{ar}
408 If you use the single command-line option @samp{-M} with @code{ar}, you
409 can control its operation with a rudimentary command language. This
410 form of @code{ar} operates interactively if standard input is coming
411 directly from a terminal. During interactive use, @code{ar} prompts for
412 input (the prompt is @samp{AR >}), and continues executing even after
413 errors. If you redirect standard input to a script file, no prompts are
414 issued, and @code{ar} abandons execution (with a nonzero exit code)
415 on any error.
416
417 The @code{ar} command language is @emph{not} designed to be equivalent
418 to the command-line options; in fact, it provides somewhat less control
419 over archives. The only purpose of the command language is to ease the
420 transition to @sc{gnu} @code{ar} for developers who already have scripts
421 written for the MRI ``librarian'' program.
422
423 The syntax for the @code{ar} command language is straightforward:
424 @itemize @bullet
425 @item
426 commands are recognized in upper or lower case; for example, @code{LIST}
427 is the same as @code{list}. In the following descriptions, commands are
428 shown in upper case for clarity.
429
430 @item
431 a single command may appear on each line; it is the first word on the
432 line.
433
434 @item
435 empty lines are allowed, and have no effect.
436
437 @item
438 comments are allowed; text after either of the characters @samp{*}
439 or @samp{;} is ignored.
440
441 @item
442 Whenever you use a list of names as part of the argument to an @code{ar}
443 command, you can separate the individual names with either commas or
444 blanks. Commas are shown in the explanations below, for clarity.
445
446 @item
447 @samp{+} is used as a line continuation character; if @samp{+} appears
448 at the end of a line, the text on the following line is considered part
449 of the current command.
450 @end itemize
451
452 Here are the commands you can use in @code{ar} scripts, or when using
453 @code{ar} interactively. Three of them have special significance:
454
455 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
456 a temporary file required for most of the other commands.
457
458 @code{SAVE} commits the changes so far specified by the script. Prior
459 to @code{SAVE}, commands affect only the temporary copy of the current
460 archive.
461
462 @table @code
463 @item ADDLIB @var{archive}
464 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
465 Add all the contents of @var{archive} (or, if specified, each named
466 @var{module} from @var{archive}) to the current archive.
467
468 Requires prior use of @code{OPEN} or @code{CREATE}.
469
470 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
471 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
472 @c else like "ar q..."
473 Add each named @var{member} as a module in the current archive.
474
475 Requires prior use of @code{OPEN} or @code{CREATE}.
476
477 @item CLEAR
478 Discard the contents of the current archive, cancelling the effect of
479 any operations since the last @code{SAVE}. May be executed (with no
480 effect) even if no current archive is specified.
481
482 @item CREATE @var{archive}
483 Creates an archive, and makes it the current archive (required for many
484 other commands). The new archive is created with a temporary name; it
485 is not actually saved as @var{archive} until you use @code{SAVE}.
486 You can overwrite existing archives; similarly, the contents of any
487 existing file named @var{archive} will not be destroyed until @code{SAVE}.
488
489 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
490 Delete each listed @var{module} from the current archive; equivalent to
491 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
492
493 Requires prior use of @code{OPEN} or @code{CREATE}.
494
495 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
496 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
497 List each named @var{module} present in @var{archive}. The separate
498 command @code{VERBOSE} specifies the form of the output: when verbose
499 output is off, output is like that of @samp{ar -t @var{archive}
500 @var{module}@dots{}}. When verbose output is on, the listing is like
501 @samp{ar -tv @var{archive} @var{module}@dots{}}.
502
503 Output normally goes to the standard output stream; however, if you
504 specify @var{outputfile} as a final argument, @code{ar} directs the
505 output to that file.
506
507 @item END
508 Exit from @code{ar}, with a @code{0} exit code to indicate successful
509 completion. This command does not save the output file; if you have
510 changed the current archive since the last @code{SAVE} command, those
511 changes are lost.
512
513 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
514 Extract each named @var{module} from the current archive, writing them
515 into the current directory as separate files. Equivalent to @samp{ar -x
516 @var{archive} @var{module}@dots{}}.
517
518 Requires prior use of @code{OPEN} or @code{CREATE}.
519
520 @ignore
521 @c FIXME Tokens but no commands???
522 @item FULLDIR
523
524 @item HELP
525 @end ignore
526
527 @item LIST
528 Display full contents of the current archive, in ``verbose'' style
529 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
530 tv @var{archive}}). (This single command is a @sc{gnu} @code{ld}
531 enhancement, rather than present for MRI compatibility.)
532
533 Requires prior use of @code{OPEN} or @code{CREATE}.
534
535 @item OPEN @var{archive}
536 Opens an existing archive for use as the current archive (required for
537 many other commands). Any changes as the result of subsequent commands
538 will not actually affect @var{archive} until you next use @code{SAVE}.
539
540 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
541 In the current archive, replace each existing @var{module} (named in
542 the @code{REPLACE} arguments) from files in the current working directory.
543 To execute this command without errors, both the file, and the module in
544 the current archive, must exist.
545
546 Requires prior use of @code{OPEN} or @code{CREATE}.
547
548 @item VERBOSE
549 Toggle an internal flag governing the output from @code{DIRECTORY}.
550 When the flag is on, @code{DIRECTORY} output matches output from
551 @samp{ar -tv }@dots{}.
552
553 @item SAVE
554 Commit your changes to the current archive, and actually save it as a
555 file with the name specified in the last @code{CREATE} or @code{OPEN}
556 command.
557
558 Requires prior use of @code{OPEN} or @code{CREATE}.
559
560 @end table
561
562 @iftex
563 @node ld
564 @chapter ld
565 @cindex linker
566 @kindex ld
567 The @sc{gnu} linker @code{ld} is now described in a separate manual.
568 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
569 @end iftex
570
571 @node nm
572 @chapter nm
573 @cindex symbols
574 @kindex nm
575
576 @smallexample
577 nm [ -a | --debug-syms ] [ -g | --extern-only ]
578 [ -B ] [ -C | --demangle ] [ -D | --dynamic ]
579 [ -s | --print-armap ] [ -A | -o | --print-file-name ]
580 [ -n | -v | --numeric-sort ] [ -p | --no-sort ]
581 [ -r | --reverse-sort ] [ --size-sort ] [ -u | --undefined-only ]
582 [ -t @var{radix} | --radix=@var{radix} ] [ -P | --portability ]
583 [ --target=@var{bfdname} ] [ -f @var{format} | --format=@var{format} ]
584 [ --defined-only ] [-l | --line-numbers ]
585 [ --no-demangle ] [ -V | --version ] [ --help ] [ @var{objfile}@dots{} ]
586 @end smallexample
587
588 @sc{gnu} @code{nm} lists the symbols from object files @var{objfile}@dots{}.
589 If no object files are listed as arguments, @code{nm} assumes
590 @file{a.out}.
591
592 For each symbol, @code{nm} shows:
593
594 @itemize @bullet
595 @item
596 The symbol value, in the radix selected by options (see below), or
597 hexadecimal by default.
598
599 @item
600 The symbol type. At least the following types are used; others are, as
601 well, depending on the object file format. If lowercase, the symbol is
602 local; if uppercase, the symbol is global (external).
603
604 @c Some more detail on exactly what these symbol types are used for
605 @c would be nice.
606 @table @code
607 @item A
608 The symbol's value is absolute, and will not be changed by further
609 linking.
610
611 @item B
612 The symbol is in the uninitialized data section (known as BSS).
613
614 @item C
615 The symbol is common. Common symbols are uninitialized data. When
616 linking, multiple common symbols may appear with the same name. If the
617 symbol is defined anywhere, the common symbols are treated as undefined
618 references. For more details on common symbols, see the discussion of
619 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
620
621 @item D
622 The symbol is in the initialized data section.
623
624 @item G
625 The symbol is in an initialized data section for small objects. Some
626 object file formats permit more efficient access to small data objects,
627 such as a global int variable as opposed to a large global array.
628
629 @item I
630 The symbol is an indirect reference to another symbol. This is a GNU
631 extension to the a.out object file format which is rarely used.
632
633 @item N
634 The symbol is a debugging symbol.
635
636 @item R
637 The symbol is in a read only data section.
638
639 @item S
640 The symbol is in an uninitialized data section for small objects.
641
642 @item T
643 The symbol is in the text (code) section.
644
645 @item U
646 The symbol is undefined.
647
648 @item W
649 The symbol is weak. When a weak defined symbol is linked with a normal
650 defined symbol, the normal defined symbol is used with no error. When a
651 weak undefined symbol is linked and the symbol is not defined, the value
652 of the weak symbol becomes zero with no error.
653
654 @item -
655 The symbol is a stabs symbol in an a.out object file. In this case, the
656 next values printed are the stabs other field, the stabs desc field, and
657 the stab type. Stabs symbols are used to hold debugging information;
658 for more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
659 ``stabs'' debug format}.
660
661 @item ?
662 The symbol type is unknown, or object file format specific.
663 @end table
664
665 @item
666 The symbol name.
667 @end itemize
668
669 The long and short forms of options, shown here as alternatives, are
670 equivalent.
671
672 @table @code
673 @item -A
674 @itemx -o
675 @itemx --print-file-name
676 @cindex input file name
677 @cindex file name
678 @cindex source file name
679 Precede each symbol by the name of the input file (or archive element)
680 in which it was found, rather than identifying the input file once only,
681 before all of its symbols.
682
683 @item -a
684 @itemx --debug-syms
685 @cindex debugging symbols
686 Display all symbols, even debugger-only symbols; normally these are not
687 listed.
688
689 @item -B
690 @cindex @code{nm} format
691 @cindex @code{nm} compatibility
692 The same as @samp{--format=bsd} (for compatibility with the MIPS @code{nm}).
693
694 @item -C
695 @itemx --demangle
696 @cindex demangling C++ symbols
697 Decode (@dfn{demangle}) low-level symbol names into user-level names.
698 Besides removing any initial underscore prepended by the system, this
699 makes C++ function names readable. @xref{c++filt}, for more information
700 on demangling.
701
702 @item --no-demangle
703 Do not demangle low-level symbol names. This is the default.
704
705 @item -D
706 @itemx --dynamic
707 @cindex dynamic symbols
708 Display the dynamic symbols rather than the normal symbols. This is
709 only meaningful for dynamic objects, such as certain types of shared
710 libraries.
711
712 @item -f @var{format}
713 @itemx --format=@var{format}
714 @cindex @code{nm} format
715 @cindex @code{nm} compatibility
716 Use the output format @var{format}, which can be @code{bsd},
717 @code{sysv}, or @code{posix}. The default is @code{bsd}.
718 Only the first character of @var{format} is significant; it can be
719 either upper or lower case.
720
721 @item -g
722 @itemx --extern-only
723 @cindex external symbols
724 Display only external symbols.
725
726 @item -l
727 @itemx --line-numbers
728 @cindex symbol line numbers
729 For each symbol, use debugging information to try to find a filename and
730 line number. For a defined symbol, look for the line number of the
731 address of the symbol. For an undefined symbol, look for the line
732 number of a relocation entry which refers to the symbol. If line number
733 information can be found, print it after the other symbol information.
734
735 @item -n
736 @itemx -v
737 @itemx --numeric-sort
738 Sort symbols numerically by their addresses, rather than alphabetically
739 by their names.
740
741 @item -p
742 @itemx --no-sort
743 @cindex sorting symbols
744 Do not bother to sort the symbols in any order; print them in the order
745 encountered.
746
747 @item -P
748 @itemx --portability
749 Use the POSIX.2 standard output format instead of the default format.
750 Equivalent to @samp{-f posix}.
751
752 @item -s
753 @itemx --print-armap
754 @cindex symbol index, listing
755 When listing symbols from archive members, include the index: a mapping
756 (stored in the archive by @code{ar} or @code{ranlib}) of which modules
757 contain definitions for which names.
758
759 @item -r
760 @itemx --reverse-sort
761 Reverse the order of the sort (whether numeric or alphabetic); let the
762 last come first.
763
764 @item --size-sort
765 Sort symbols by size. The size is computed as the difference between
766 the value of the symbol and the value of the symbol with the next higher
767 value. The size of the symbol is printed, rather than the value.
768
769 @item -t @var{radix}
770 @itemx --radix=@var{radix}
771 Use @var{radix} as the radix for printing the symbol values. It must be
772 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
773
774 @item --target=@var{bfdname}
775 @cindex object code format
776 Specify an object code format other than your system's default format.
777 @xref{Target Selection}, for more information.
778
779 @item -u
780 @itemx --undefined-only
781 @cindex external symbols
782 @cindex undefined symbols
783 Display only undefined symbols (those external to each object file).
784
785 @item --defined-only
786 @cindex external symbols
787 @cindex undefined symbols
788 Display only defined symbols for each object file.
789
790 @item -V
791 @itemx --version
792 Show the version number of @code{nm} and exit.
793
794 @item --help
795 Show a summary of the options to @code{nm} and exit.
796 @end table
797
798 @node objcopy
799 @chapter objcopy
800
801 @smallexample
802 objcopy [ -F @var{bfdname} | --target=@var{bfdname} ]
803 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
804 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
805 [ -S | --strip-all ] [ -g | --strip-debug ]
806 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
807 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
808 [ -x | --discard-all ] [ -X | --discard-locals ]
809 [ -b @var{byte} | --byte=@var{byte} ]
810 [ -i @var{interleave} | --interleave=@var{interleave} ]
811 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
812 [ --debugging ]
813 [ --gap-fill=@var{val} ] [ --pad-to=@var{address} ]
814 [ --set-start=@var{val} ] [ --adjust-start=@var{incr} ]
815 [ --adjust-vma=@var{incr} ]
816 [ --adjust-section-vma=@var{section}@{=,+,-@}@var{val} ]
817 [ --adjust-warnings ] [ --no-adjust-warnings ]
818 [ --set-section-flags=@var{section}=@var{flags} ]
819 [ --add-section=@var{sectionname}=@var{filename} ]
820 [ --change-leading-char ] [ --remove-leading-char ]
821 [ --weaken ]
822 [ -v | --verbose ] [ -V | --version ] [ --help ]
823 @var{infile} [@var{outfile}]
824 @end smallexample
825
826 The @sc{gnu} @code{objcopy} utility copies the contents of an object
827 file to another. @code{objcopy} uses the @sc{gnu} @sc{bfd} Library to
828 read and write the object files. It can write the destination object
829 file in a format different from that of the source object file. The
830 exact behavior of @code{objcopy} is controlled by command-line options.
831
832 @code{objcopy} creates temporary files to do its translations and
833 deletes them afterward. @code{objcopy} uses @sc{bfd} to do all its
834 translation work; it has access to all the formats described in @sc{bfd}
835 and thus is able to recognize most formats without being told
836 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
837
838 @code{objcopy} can be used to generate S-records by using an output
839 target of @samp{srec} (e.g., use @samp{-O srec}).
840
841 @code{objcopy} can be used to generate a raw binary file by using an
842 output target of @samp{binary} (e.g., use @samp{-O binary}). When
843 @code{objcopy} generates a raw binary file, it will essentially produce
844 a memory dump of the contents of the input object file. All symbols and
845 relocation information will be discarded. The memory dump will start at
846 the load address of the lowest section copied into the output file.
847
848 When generating an S-record or a raw binary file, it may be helpful to
849 use @samp{-S} to remove sections containing debugging information. In
850 some cases @samp{-R} will be useful to remove sections which contain
851 information which is not needed by the binary file.
852
853 @table @code
854 @item @var{infile}
855 @itemx @var{outfile}
856 The source and output files, respectively.
857 If you do not specify @var{outfile}, @code{objcopy} creates a
858 temporary file and destructively renames the result with
859 the name of @var{infile}.
860
861 @item -I @var{bfdname}
862 @itemx --input-target=@var{bfdname}
863 Consider the source file's object format to be @var{bfdname}, rather than
864 attempting to deduce it. @xref{Target Selection}, for more information.
865
866 @item -O @var{bfdname}
867 @itemx --output-target=@var{bfdname}
868 Write the output file using the object format @var{bfdname}.
869 @xref{Target Selection}, for more information.
870
871 @item -F @var{bfdname}
872 @itemx --target=@var{bfdname}
873 Use @var{bfdname} as the object format for both the input and the output
874 file; i.e., simply transfer data from source to destination with no
875 translation. @xref{Target Selection}, for more information.
876
877 @item -R @var{sectionname}
878 @itemx --remove-section=@var{sectionname}
879 Remove any section named @var{sectionname} from the output file. This
880 option may be given more than once. Note that using this option
881 inappropriately may make the output file unusable.
882
883 @item -S
884 @itemx --strip-all
885 Do not copy relocation and symbol information from the source file.
886
887 @item -g
888 @itemx --strip-debug
889 Do not copy debugging symbols from the source file.
890
891 @item --strip-unneeded
892 Strip all symbols that are not needed for relocation processing.
893
894 @item -K @var{symbolname}
895 @itemx --keep-symbol=@var{symbolname}
896 Copy only symbol @var{symbolname} from the source file. This option may
897 be given more than once.
898
899 @item -N @var{symbolname}
900 @itemx --strip-symbol=@var{symbolname}
901 Do not copy symbol @var{symbolname} from the source file. This option
902 may be given more than once, and may be combined with strip options
903 other than @code{-K}.
904
905 @item -x
906 @itemx --discard-all
907 Do not copy non-global symbols from the source file.
908 @c FIXME any reason to prefer "non-global" to "local" here?
909
910 @item -X
911 @itemx --discard-locals
912 Do not copy compiler-generated local symbols.
913 (These usually start with @samp{L} or @samp{.}.)
914
915 @item -b @var{byte}
916 @itemx --byte=@var{byte}
917 Keep only every @var{byte}th byte of the input file (header data is not
918 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
919 where @var{interleave} is given by the @samp{-i} or @samp{--interleave}
920 option, or the default of 4. This option is useful for creating files
921 to program @sc{rom}. It is typically used with an @code{srec} output
922 target.
923
924 @item -i @var{interleave}
925 @itemx --interleave=@var{interleave}
926 Only copy one out of every @var{interleave} bytes. Select which byte to
927 copy with the @var{-b} or @samp{--byte} option. The default is 4.
928 @code{objcopy} ignores this option if you do not specify either @samp{-b} or
929 @samp{--byte}.
930
931 @item --debugging
932 Convert debugging information, if possible. This is not the default
933 because only certain debugging formats are supported, and the
934 conversion process can be time consuming.
935
936 @item --gap-fill @var{val}
937 Fill gaps between sections with @var{val}. This is done by increasing
938 the size of the section with the lower address, and filling in the extra
939 space created with @var{val}.
940
941 @item --pad-to @var{address}
942 Pad the output file up to the virtual address @var{address}. This is
943 done by increasing the size of the last section. The extra space is
944 filled in with the value specified by @samp{--gap-fill} (default zero).
945
946 @item --set-start @var{val}
947 Set the address of the new file to @var{val}. Not all object file
948 formats support setting the start address.
949
950 @item --adjust-start @var{incr}
951 Adjust the start address by adding @var{incr}. Not all object file
952 formats support setting the start address.
953
954 @item --adjust-vma @var{incr}
955 Adjust the address of all sections, as well as the start address, by
956 adding @var{incr}. Some object file formats do not permit section
957 addresses to be changed arbitrarily. Note that this does not relocate
958 the sections; if the program expects sections to be loaded at a certain
959 address, and this option is used to change the sections such that they
960 are loaded at a different address, the program may fail.
961
962 @item --adjust-section-vma @var{section}@{=,+,-@}@var{val}
963 Set or adjust the address of the named @var{section}. If @samp{=} is
964 used, the section address is set to @var{val}. Otherwise, @var{val} is
965 added to or subtracted from the section address. See the comments under
966 @samp{--adjust-vma}, above. If @var{section} does not exist in the
967 input file, a warning will be issued, unless @samp{--no-adjust-warnings}
968 is used.
969
970 @item --adjust-warnings
971 If @samp{--adjust-section-vma} is used, and the named section does not
972 exist, issue a warning. This is the default.
973
974 @item --no-adjust-warnings
975 Do not issue a warning if @samp{--adjust-section-vma} is used, even if
976 the named section does not exist.
977
978 @item --set-section-flags @var{section}=@var{flags}
979 Set the flags for the named section. The @var{flags} argument is a
980 comma separated string of flag names. The recognized names are
981 @samp{alloc}, @samp{load}, @samp{readonly}, @samp{code}, @samp{data},
982 and @samp{rom}. Not all flags are meaningful for all object file
983 formats.
984
985 @item --add-section @var{sectionname}=@var{filename}
986 Add a new section named @var{sectionname} while copying the file. The
987 contents of the new section are taken from the file @var{filename}. The
988 size of the section will be the size of the file. This option only
989 works on file formats which can support sections with arbitrary names.
990
991 @item --change-leading-char
992 Some object file formats use special characters at the start of
993 symbols. The most common such character is underscore, which compilers
994 often add before every symbol. This option tells @code{objcopy} to
995 change the leading character of every symbol when it converts between
996 object file formats. If the object file formats use the same leading
997 character, this option has no effect. Otherwise, it will add a
998 character, or remove a character, or change a character, as
999 appropriate.
1000
1001 @item --remove-leading-char
1002 If the first character of a global symbol is a special symbol leading
1003 character used by the object file format, remove the character. The
1004 most common symbol leading character is underscore. This option will
1005 remove a leading underscore from all global symbols. This can be useful
1006 if you want to link together objects of different file formats with
1007 different conventions for symbol names. This is different from
1008 @code{--change-leading-char} because it always changes the symbol name
1009 when appropriate, regardless of the object file format of the output
1010 file.
1011
1012 @item --weaken
1013 Change all global symbols in the file to be weak. This can be useful
1014 when building an object which will be linked against other objects using
1015 the @code{-R} option to the linker. This option is only effective when
1016 using an object file format which supports weak symbols.
1017
1018 @item -V
1019 @itemx --version
1020 Show the version number of @code{objcopy}.
1021
1022 @item -v
1023 @itemx --verbose
1024 Verbose output: list all object files modified. In the case of
1025 archives, @samp{objcopy -V} lists all members of the archive.
1026
1027 @item --help
1028 Show a summary of the options to @code{objcopy}.
1029 @end table
1030
1031 @node objdump
1032 @chapter objdump
1033
1034 @cindex object file information
1035 @kindex objdump
1036
1037 @smallexample
1038 objdump [ -a | --archive-headers ]
1039 [ -b @var{bfdname} | --target=@var{bfdname} ] [ --debugging ]
1040 [ -d | --disassemble ] [ -D | --disassemble-all ]
1041 [ -EB | -EL | --endian=@{big | little @} ]
1042 [ -f | --file-headers ]
1043 [ -h | --section-headers | --headers ] [ -i | --info ]
1044 [ -j @var{section} | --section=@var{section} ]
1045 [ -l | --line-numbers ] [ -S | --source ]
1046 [ -m @var{machine} | --architecture=@var{machine} ]
1047 [ -r | --reloc ] [ -R | --dynamic-reloc ]
1048 [ -s | --full-contents ] [ --stabs ]
1049 [ -t | --syms ] [ -T | --dynamic-syms ] [ -x | --all-headers ]
1050 [ -w | --wide ] [ --start-address=@var{address} ]
1051 [ --stop-address=@var{address} ]
1052 [ --prefix-addresses] [ --show-raw-insn ]
1053 [ --version ] [ --help ]
1054 @var{objfile}@dots{}
1055 @end smallexample
1056
1057 @code{objdump} displays information about one or more object files.
1058 The options control what particular information to display. This
1059 information is mostly useful to programmers who are working on the
1060 compilation tools, as opposed to programmers who just want their
1061 program to compile and work.
1062
1063 @var{objfile}@dots{} are the object files to be examined. When you
1064 specify archives, @code{objdump} shows information on each of the member
1065 object files.
1066
1067 The long and short forms of options, shown here as alternatives, are
1068 equivalent. At least one option besides @samp{-l} must be given.
1069
1070 @table @code
1071 @item -a
1072 @itemx --archive-header
1073 @cindex archive headers
1074 If any of the @var{objfile} files are archives, display the archive
1075 header information (in a format similar to @samp{ls -l}). Besides the
1076 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1077 the object file format of each archive member.
1078
1079 @item -b @var{bfdname}
1080 @itemx --target=@var{bfdname}
1081 @cindex object code format
1082 Specify that the object-code format for the object files is
1083 @var{bfdname}. This option may not be necessary; @var{objdump} can
1084 automatically recognize many formats.
1085
1086 For example,
1087 @example
1088 objdump -b oasys -m vax -h fu.o
1089 @end example
1090 @noindent
1091 displays summary information from the section headers (@samp{-h}) of
1092 @file{fu.o}, which is explicitly identified (@samp{-m}) as a VAX object
1093 file in the format produced by Oasys compilers. You can list the
1094 formats available with the @samp{-i} option.
1095 @xref{Target Selection}, for more information.
1096
1097 @item --debugging
1098 Display debugging information. This attempts to parse debugging
1099 information stored in the file and print it out using a C like syntax.
1100 Only certain types of debugging information have been implemented.
1101
1102 @item -d
1103 @itemx --disassemble
1104 @cindex disassembling object code
1105 @cindex machine instructions
1106 Display the assembler mnemonics for the machine instructions from
1107 @var{objfile}. This option only disassembles those sections which are
1108 expected to contain instructions.
1109
1110 @item -D
1111 @itemx --disassemble-all
1112 Like @samp{-d}, but disassemble the contents of all sections, not just
1113 those expected to contain instructions.
1114
1115 @item -EB
1116 @itemx -EL
1117 @itemx --endian=@{big|little@}
1118 @cindex endianness
1119 @cindex disassembly endianness
1120 Specify the endianness of the object files. This only affects
1121 disassembly. This can be useful when disassembling a file format which
1122 does not describe endianness information, such as S-records.
1123
1124 @item -f
1125 @itemx --file-header
1126 @cindex object file header
1127 Display summary information from the overall header of
1128 each of the @var{objfile} files.
1129
1130 @item -h
1131 @itemx --section-header
1132 @itemx --header
1133 @cindex section headers
1134 Display summary information from the section headers of the
1135 object file.
1136
1137 File segments may be relocated to nonstandard addresses, for example by
1138 using the @samp{-Ttext}, @samp{-Tdata}, or @samp{-Tbss} options to
1139 @code{ld}. However, some object file formats, such as a.out, do not
1140 store the starting address of the file segments. In those situations,
1141 although @code{ld} relocates the sections correctly, using @samp{objdump
1142 -h} to list the file section headers cannot show the correct addresses.
1143 Instead, it shows the usual addresses, which are implicit for the
1144 target.
1145
1146 @item --help
1147 Print a summary of the options to @code{objdump} and exit.
1148
1149 @item -i
1150 @itemx --info
1151 @cindex architectures available
1152 @cindex object formats available
1153 Display a list showing all architectures and object formats available
1154 for specification with @samp{-b} or @samp{-m}.
1155
1156 @item -j @var{name}
1157 @itemx --section=@var{name}
1158 @cindex section information
1159 Display information only for section @var{name}.
1160
1161 @item -l
1162 @itemx --line-numbers
1163 @cindex source filenames for object files
1164 Label the display (using debugging information) with the filename and
1165 source line numbers corresponding to the object code or relocs shown.
1166 Only useful with @samp{-d}, @samp{-D}, or @samp{-r}.
1167
1168 @item -m @var{machine}
1169 @itemx --architecture=@var{machine}
1170 @cindex architecture
1171 @cindex disassembly architecture
1172 Specify the architecture to use when disassembling object files. This
1173 can be useful when disasembling object files which do not describe
1174 architecture information, such as S-records. You can list the available
1175 architectures with the @samp{-i} option.
1176
1177 @item --prefix-addresses
1178 When disassembling, print the complete address on each line. This is
1179 the older disassembly format.
1180
1181 @item -r
1182 @itemx --reloc
1183 @cindex relocation entries, in object file
1184 Print the relocation entries of the file. If used with @samp{-d} or
1185 @samp{-D}, the relocations are printed interspersed with the
1186 disassembly.
1187
1188 @item -R
1189 @itemx --dynamic-reloc
1190 @cindex dynamic relocation entries, in object file
1191 Print the dynamic relocation entries of the file. This is only
1192 meaningful for dynamic objects, such as certain types of shared
1193 libraries.
1194
1195 @item -s
1196 @itemx --full-contents
1197 @cindex sections, full contents
1198 @cindex object file sections
1199 Display the full contents of any sections requested.
1200
1201 @item -S
1202 @itemx --source
1203 @cindex source disassembly
1204 @cindex disassembly, with source
1205 Display source code intermixed with disassembly, if possible. Implies
1206 @samp{-d}.
1207
1208 @item --show-raw-insn
1209 When disassembling instructions, print the instruction in hex as well as
1210 in symbolic form. This is the default except when
1211 @code{--prefix-addresses} is used.
1212
1213 @item --stabs
1214 @cindex stab
1215 @cindex .stab
1216 @cindex debug symbols
1217 @cindex ELF object file format
1218 Display the full contents of any sections requested. Display the
1219 contents of the .stab and .stab.index and .stab.excl sections from an
1220 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1221 @code{.stab} debugging symbol-table entries are carried in an ELF
1222 section. In most other file formats, debugging symbol-table entries are
1223 interleaved with linkage symbols, and are visible in the @samp{--syms}
1224 output. For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1225 Overview,stabs.info, The ``stabs'' debug format}.
1226
1227 @item --start-address=@var{address}
1228 @cindex start-address
1229 Start displaying data at the specified address. This affects the output
1230 of the @code{-d}, @code{-r} and @code{-s} options.
1231
1232 @item --stop-address=@var{address}
1233 @cindex stop-address
1234 Stop displaying data at the specified address. This affects the output
1235 of the @code{-d}, @code{-r} and @code{-s} options.
1236
1237 @item -t
1238 @itemx --syms
1239 @cindex symbol table entries, printing
1240 Print the symbol table entries of the file.
1241 This is similar to the information provided by the @samp{nm} program.
1242
1243 @item -T
1244 @itemx --dynamic-syms
1245 @cindex dynamic symbol table entries, printing
1246 Print the dynamic symbol table entries of the file. This is only
1247 meaningful for dynamic objects, such as certain types of shared
1248 libraries. This is similar to the information provided by the @samp{nm}
1249 program when given the @samp{-D} (@samp{--dynamic}) option.
1250
1251 @item --version
1252 Print the version number of @code{objdump} and exit.
1253
1254 @item -x
1255 @itemx --all-header
1256 @cindex all header information, object file
1257 @cindex header information, all
1258 Display all available header information, including the symbol table and
1259 relocation entries. Using @samp{-x} is equivalent to specifying all of
1260 @samp{-a -f -h -r -t}.
1261
1262 @item -w
1263 @item --wide
1264 @cindex wide output, printing
1265 Format some lines for output devices that have more than 80 columns.
1266 @end table
1267
1268 @node ranlib
1269 @chapter ranlib
1270
1271 @kindex ranlib
1272 @cindex archive contents
1273 @cindex symbol index
1274
1275 @smallexample
1276 ranlib [-vV] @var{archive}
1277 @end smallexample
1278
1279 @code{ranlib} generates an index to the contents of an archive and
1280 stores it in the archive. The index lists each symbol defined by a
1281 member of an archive that is a relocatable object file.
1282
1283 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1284
1285 An archive with such an index speeds up linking to the library and
1286 allows routines in the library to call each other without regard to
1287 their placement in the archive.
1288
1289 The @sc{gnu} @code{ranlib} program is another form of @sc{gnu} @code{ar}; running
1290 @code{ranlib} is completely equivalent to executing @samp{ar -s}.
1291 @xref{ar}.
1292
1293 @table @code
1294 @item -v
1295 @itemx -V
1296 Show the version number of @code{ranlib}.
1297 @end table
1298
1299 @node size
1300 @chapter size
1301
1302 @kindex size
1303 @cindex section sizes
1304
1305 @smallexample
1306 size [ -A | -B | --format=@var{compatibility} ]
1307 [ --help ] [ -d | -o | -x | --radix=@var{number} ]
1308 [ --target=@var{bfdname} ] [ -V | --version ]
1309 @var{objfile}@dots{}
1310 @end smallexample
1311
1312 The @sc{gnu} @code{size} utility lists the section sizes---and the total
1313 size---for each of the object or archive files @var{objfile} in its
1314 argument list. By default, one line of output is generated for each
1315 object file or each module in an archive.
1316
1317 @var{objfile}@dots{} are the object files to be examined.
1318
1319 The command line options have the following meanings:
1320
1321 @table @code
1322 @item -A
1323 @itemx -B
1324 @itemx --format=@var{compatibility}
1325 @cindex @code{size} display format
1326 Using one of these options, you can choose whether the output from @sc{gnu}
1327 @code{size} resembles output from System V @code{size} (using @samp{-A},
1328 or @samp{--format=sysv}), or Berkeley @code{size} (using @samp{-B}, or
1329 @samp{--format=berkeley}). The default is the one-line format similar to
1330 Berkeley's.
1331 @c Bonus for doc-source readers: you can also say --format=strange (or
1332 @c anything else that starts with 's') for sysv, and --format=boring (or
1333 @c anything else that starts with 'b') for Berkeley.
1334
1335 Here is an example of the Berkeley (default) format of output from
1336 @code{size}:
1337 @smallexample
1338 size --format=Berkeley ranlib size
1339 text data bss dec hex filename
1340 294880 81920 11592 388392 5ed28 ranlib
1341 294880 81920 11888 388688 5ee50 size
1342 @end smallexample
1343
1344 @noindent
1345 This is the same data, but displayed closer to System V conventions:
1346
1347 @smallexample
1348 size --format=SysV ranlib size
1349 ranlib :
1350 section size addr
1351 .text 294880 8192
1352 .data 81920 303104
1353 .bss 11592 385024
1354 Total 388392
1355
1356
1357 size :
1358 section size addr
1359 .text 294880 8192
1360 .data 81920 303104
1361 .bss 11888 385024
1362 Total 388688
1363 @end smallexample
1364
1365 @item --help
1366 Show a summary of acceptable arguments and options.
1367
1368 @item -d
1369 @itemx -o
1370 @itemx -x
1371 @itemx --radix=@var{number}
1372 @cindex @code{size} number format
1373 @cindex radix for section sizes
1374 Using one of these options, you can control whether the size of each
1375 section is given in decimal (@samp{-d}, or @samp{--radix=10}); octal
1376 (@samp{-o}, or @samp{--radix=8}); or hexadecimal (@samp{-x}, or
1377 @samp{--radix=16}). In @samp{--radix=@var{number}}, only the three
1378 values (8, 10, 16) are supported. The total size is always given in two
1379 radices; decimal and hexadecimal for @samp{-d} or @samp{-x} output, or
1380 octal and hexadecimal if you're using @samp{-o}.
1381
1382 @item --target=@var{bfdname}
1383 @cindex object code format
1384 Specify that the object-code format for @var{objfile} is
1385 @var{bfdname}. This option may not be necessary; @code{size} can
1386 automatically recognize many formats.
1387 @xref{Target Selection}, for more information.
1388
1389 @item -V
1390 @itemx --version
1391 Display the version number of @code{size}.
1392 @end table
1393
1394 @node strings
1395 @chapter strings
1396 @kindex strings
1397 @cindex listings strings
1398 @cindex printing strings
1399 @cindex strings, printing
1400
1401 @smallexample
1402 strings [-afov] [-@var{min-len}] [-n @var{min-len}] [-t @var{radix}] [-]
1403 [--all] [--print-file-name] [--bytes=@var{min-len}]
1404 [--radix=@var{radix}] [--target=@var{bfdname}]
1405 [--help] [--version] @var{file}@dots{}
1406 @end smallexample
1407
1408 For each @var{file} given, @sc{gnu} @code{strings} prints the printable
1409 character sequences that are at least 4 characters long (or the number
1410 given with the options below) and are followed by an unprintable
1411 character. By default, it only prints the strings from the initialized
1412 and loaded sections of object files; for other types of files, it prints
1413 the strings from the whole file.
1414
1415 @code{strings} is mainly useful for determining the contents of non-text
1416 files.
1417
1418 @table @code
1419 @item -a
1420 @itemx --all
1421 @itemx -
1422 Do not scan only the initialized and loaded sections of object files;
1423 scan the whole files.
1424
1425 @item -f
1426 @itemx --print-file-name
1427 Print the name of the file before each string.
1428
1429 @item --help
1430 Print a summary of the program usage on the standard output and exit.
1431
1432 @itemx -@var{min-len}
1433 @item -n @var{min-len}
1434 @itemx --bytes=@var{min-len}
1435 Print sequences of characters that are at least @var{min-len} characters
1436 long, instead of the default 4.
1437
1438 @item -o
1439 Like @samp{-t o}. Some other versions of @code{strings} have @samp{-o}
1440 act like @samp{-t d} instead. Since we can not be compatible with both
1441 ways, we simply chose one.
1442
1443 @item -t @var{radix}
1444 @itemx --radix=@var{radix}
1445 Print the offset within the file before each string. The single
1446 character argument specifies the radix of the offset---@samp{o} for
1447 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
1448
1449 @item --target=@var{bfdname}
1450 @cindex object code format
1451 Specify an object code format other than your system's default format.
1452 @xref{Target Selection}, for more information.
1453
1454 @item -v
1455 @itemx --version
1456 Print the program version number on the standard output and exit.
1457 @end table
1458
1459 @node strip
1460 @chapter strip
1461
1462 @kindex strip
1463 @cindex removing symbols
1464 @cindex discarding symbols
1465 @cindex symbols, discarding
1466
1467 @smallexample
1468 strip [ -F @var{bfdname} | --target=@var{bfdname} | --target=@var{bfdname} ]
1469 [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1470 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1471 [ -s | --strip-all ] [ -S | -g | --strip-debug ]
1472 [ -K @var{symbolname} | --keep-symbol=@var{symbolname} ]
1473 [ -N @var{symbolname} | --strip-symbol=@var{symbolname} ]
1474 [ -x | --discard-all ] [ -X | --discard-locals ]
1475 [ -R @var{sectionname} | --remove-section=@var{sectionname} ]
1476 [ -o @var{file} ]
1477 [ -v | --verbose ] [ -V | --version ] [ --help ]
1478 @var{objfile}@dots{}
1479 @end smallexample
1480
1481 @sc{gnu} @code{strip} discards all symbols from object files
1482 @var{objfile}. The list of object files may include archives.
1483 At least one object file must be given.
1484
1485 @code{strip} modifies the files named in its argument,
1486 rather than writing modified copies under different names.
1487
1488 @table @code
1489 @item -F @var{bfdname}
1490 @itemx --target=@var{bfdname}
1491 Treat the original @var{objfile} as a file with the object
1492 code format @var{bfdname}, and rewrite it in the same format.
1493 @xref{Target Selection}, for more information.
1494
1495 @item --help
1496 Show a summary of the options to @code{strip} and exit.
1497
1498 @item -I @var{bfdname}
1499 @itemx --input-target=@var{bfdname}
1500 Treat the original @var{objfile} as a file with the object
1501 code format @var{bfdname}.
1502 @xref{Target Selection}, for more information.
1503
1504 @item -O @var{bfdname}
1505 @itemx --output-target=@var{bfdname}
1506 Replace @var{objfile} with a file in the output format @var{bfdname}.
1507 @xref{Target Selection}, for more information.
1508
1509 @item -R @var{sectionname}
1510 @itemx --remove-section=@var{sectionname}
1511 Remove any section named @var{sectionname} from the output file. This
1512 option may be given more than once. Note that using this option
1513 inappropriately may make the output file unusable.
1514
1515 @item -s
1516 @itemx --strip-all
1517 Remove all symbols.
1518
1519 @item -g
1520 @itemx -S
1521 @itemx --strip-debug
1522 Remove debugging symbols only.
1523
1524 @item --strip-unneeded
1525 Remove all symbols that are not needed for relocation processing.
1526
1527 @item -K @var{symbolname}
1528 @itemx --keep-symbol=@var{symbolname}
1529 Keep only symbol @var{symbolname} from the source file. This option may
1530 be given more than once.
1531
1532 @item -N @var{symbolname}
1533 @itemx --strip-symbol=@var{symbolname}
1534 Remove symbol @var{symbolname} from the source file. This option may be
1535 given more than once, and may be combined with strip options other than
1536 @code{-K}.
1537
1538 @item -o @var{file}
1539 Put the stripped output in @var{file}, rather than replacing the
1540 existing file. When this argument is used, only one @var{objfile}
1541 argument may be specified.
1542
1543 @item -x
1544 @itemx --discard-all
1545 Remove non-global symbols.
1546
1547 @item -X
1548 @itemx --discard-locals
1549 Remove compiler-generated local symbols.
1550 (These usually start with @samp{L} or @samp{.}.)
1551
1552 @item -V
1553 @itemx --version
1554 Show the version number for @code{strip}.
1555
1556 @item -v
1557 @itemx --verbose
1558 Verbose output: list all object files modified. In the case of
1559 archives, @samp{strip -v} lists all members of the archive.
1560 @end table
1561
1562 @node c++filt
1563 @chapter c++filt
1564
1565 @kindex c++filt
1566 @cindex demangling C++ symbols
1567
1568 @smallexample
1569 c++filt [ -_ | --strip-underscores ]
1570 [ -n | --no-strip-underscores ]
1571 [ -s @var{format} | --format=@var{format} ]
1572 [ --help ] [ --version ] [ @var{symbol}@dots{} ]
1573 @end smallexample
1574
1575 The C++ language provides function overloading, which means that you can
1576 write many functions with the same name (providing each takes parameters
1577 of different types). All C++ function names are encoded into a
1578 low-level assembly label (this process is known as
1579 @dfn{mangling}). The @code{c++filt} program does the inverse mapping: it
1580 decodes (@dfn{demangles}) low-level names into user-level names so that
1581 the linker can keep these overloaded functions from clashing.
1582
1583 Every alphanumeric word (consisting of letters, digits, underscores,
1584 dollars, or periods) seen in the input is a potential label. If the
1585 label decodes into a C++ name, the C++ name replaces the low-level
1586 name in the output.
1587
1588 You can use @code{c++filt} to decipher individual symbols:
1589
1590 @example
1591 c++filt @var{symbol}
1592 @end example
1593
1594 If no @var{symbol} arguments are given, @code{c++filt} reads symbol
1595 names from the standard input and writes the demangled names to the
1596 standard output. All results are printed on the standard output.
1597
1598 @table @code
1599 @item -_
1600 @itemx --strip-underscores
1601 On some systems, both the C and C++ compilers put an underscore in front
1602 of every name. For example, the C name @code{foo} gets the low-level
1603 name @code{_foo}. This option removes the initial underscore. Whether
1604 @code{c++filt} removes the underscore by default is target dependent.
1605
1606 @item -n
1607 @itemx --no-strip-underscores
1608 Do not remove the initial underscore.
1609
1610 @item -s @var{format}
1611 @itemx --format=@var{format}
1612 @sc{gnu} @code{nm} can decode three different methods of mangling, used by
1613 different C++ compilers. The argument to this option selects which
1614 method it uses:
1615
1616 @table @code
1617 @item gnu
1618 the one used by the @sc{gnu} compiler (the default method)
1619 @item lucid
1620 the one used by the Lucid compiler
1621 @item arm
1622 the one specified by the C++ Annotated Reference Manual
1623 @end table
1624
1625 @item --help
1626 Print a summary of the options to @code{c++filt} and exit.
1627
1628 @item --version
1629 Print the version number of @code{c++filt} and exit.
1630 @end table
1631
1632 @quotation
1633 @emph{Warning:} @code{c++filt} is a new utility, and the details of its
1634 user interface are subject to change in future releases. In particular,
1635 a command-line option may be required in the the future to decode a name
1636 passed as an argument on the command line; in other words,
1637
1638 @example
1639 c++filt @var{symbol}
1640 @end example
1641
1642 @noindent
1643 may in a future release become
1644
1645 @example
1646 c++filt @var{option} @var{symbol}
1647 @end example
1648 @end quotation
1649
1650 @node nlmconv
1651 @chapter nlmconv
1652
1653 @code{nlmconv} converts a relocatable object file into a NetWare
1654 Loadable Module.
1655
1656 @ignore
1657 @code{nlmconv} currently works with @samp{i386} object
1658 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
1659 object files in @sc{elf}, or @code{a.out} format@footnote{
1660 @code{nlmconv} should work with any @samp{i386} or @sc{sparc} object
1661 format in the Binary File Descriptor library. It has only been tested
1662 with the above formats.}.
1663 @end ignore
1664
1665 @quotation
1666 @emph{Warning:} @code{nlmconv} is not always built as part of the binary
1667 utilities, since it is only useful for NLM targets.
1668 @end quotation
1669
1670 @smallexample
1671 nlmconv [ -I @var{bfdname} | --input-target=@var{bfdname} ]
1672 [ -O @var{bfdname} | --output-target=@var{bfdname} ]
1673 [ -T @var{headerfile} | --header-file=@var{headerfile} ]
1674 [ -d | --debug] [ -l @var{linker} | --linker=@var{linker} ]
1675 [ -h | --help ] [ -V | --version ]
1676 @var{infile} @var{outfile}
1677 @end smallexample
1678
1679 @code{nlmconv} converts the relocatable @samp{i386} object file
1680 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
1681 reading @var{headerfile} for NLM header information. For instructions
1682 on writing the NLM command file language used in header files, see the
1683 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
1684 Development and Tools Overview}, which is part of the NLM Software
1685 Developer's Kit (``NLM SDK''), available from Novell, Inc.
1686 @code{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
1687 @var{infile}; see @ref{BFD,,BFD,ld.info,Using LD}, for
1688 more information.
1689
1690 @code{nlmconv} can perform a link step. In other words, you can list
1691 more than one object file for input if you list them in the definitions
1692 file (rather than simply specifying one input file on the command line).
1693 In this case, @code{nlmconv} calls the linker for you.
1694
1695 @table @code
1696 @item -I @var{bfdname}
1697 @itemx --input-target=@var{bfdname}
1698 Object format of the input file. @code{nlmconv} can usually determine
1699 the format of a given file (so no default is necessary).
1700 @xref{Target Selection}, for more information.
1701
1702 @item -O @var{bfdname}
1703 @itemx --output-target=@var{bfdname}
1704 Object format of the output file. @code{nlmconv} infers the output
1705 format based on the input format, e.g. for a @samp{i386} input file the
1706 output format is @samp{nlm32-i386}.
1707 @xref{Target Selection}, for more information.
1708
1709 @item -T @var{headerfile}
1710 @itemx --header-file=@var{headerfile}
1711 Reads @var{headerfile} for NLM header information. For instructions on
1712 writing the NLM command file language used in header files, see@ see the
1713 @samp{linkers} section, of the @cite{NLM Development and Tools
1714 Overview}, which is part of the NLM Software Developer's Kit, available
1715 from Novell, Inc.
1716
1717 @item -d
1718 @itemx --debug
1719 Displays (on standard error) the linker command line used by @code{nlmconv}.
1720
1721 @item -l @var{linker}
1722 @itemx --linker=@var{linker}
1723 Use @var{linker} for any linking. @var{linker} can be an abosolute or a
1724 relative pathname.
1725
1726 @item -h
1727 @itemx --help
1728 Prints a usage summary.
1729
1730 @item -V
1731 @itemx --version
1732 Prints the version number for @code{nlmconv}.
1733 @end table
1734
1735 @node Selecting The Target System
1736 @chapter Selecting the target system
1737
1738 You can specify three aspects of the target system to the @sc{gnu}
1739 binary file utilities, each in several ways:
1740
1741 @itemize @bullet
1742 @item
1743 the target
1744
1745 @item
1746 the architecture
1747
1748 @item
1749 the linker emulation (which applies to the linker only)
1750 @end itemize
1751
1752 In the following summaries, the lists of ways to specify values are in
1753 order of decreasing precedence. The ways listed first override those
1754 listed later.
1755
1756 The commands to list valid values only list the values for which the
1757 programs you are running were configured. If they were configured with
1758 @samp{--enable-targets=all}, the commands list most of the available
1759 values, but a few are left out; not all targets can be configured in at
1760 once because some of them can only be configured @dfn{native} (on hosts
1761 with the same type as the target system).
1762
1763 @menu
1764 * Target Selection::
1765 * Architecture Selection::
1766 * Linker Emulation Selection::
1767 @end menu
1768
1769 @node Target Selection
1770 @section Target Selection
1771
1772 A @dfn{target} is an object file format. A given target may be
1773 supported for multiple architectures (@pxref{Architecture Selection}).
1774 A target selection may also have variations for different operating
1775 systems or architectures.
1776
1777 The command to list valid target values is @samp{objdump -i}
1778 (the first column of output contains the relevant information).
1779
1780 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
1781 @samp{a.out-sunos-big}.
1782
1783 You can also specify a target using a configuration triplet. This is
1784 the same sort of name that is passed to configure to specify a target.
1785 When you use a configuration triplet as an argument, it must be fully
1786 canonicalized. You can see the canonical version of a triplet by
1787 running the shell script @file{config.sub} which is included with the
1788 sources.
1789
1790 Some sample configuration triplets are: @samp{m68k-hp-bsd},
1791 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
1792
1793 @subheading @code{objdump} Target
1794
1795 Ways to specify:
1796
1797 @enumerate
1798 @item
1799 command line option: @samp{-b} or @samp{--target}
1800
1801 @item
1802 environment variable @code{GNUTARGET}
1803
1804 @item
1805 deduced from the input file
1806 @end enumerate
1807
1808 @subheading @code{objcopy} and @code{strip} Input Target
1809
1810 Ways to specify:
1811
1812 @enumerate
1813 @item
1814 command line options: @samp{-I} or @samp{--input-target}, or @samp{-F} or @samp{--target}
1815
1816 @item
1817 environment variable @code{GNUTARGET}
1818
1819 @item
1820 deduced from the input file
1821 @end enumerate
1822
1823 @subheading @code{objcopy} and @code{strip} Output Target
1824
1825 Ways to specify:
1826
1827 @enumerate
1828 @item
1829 command line options: @samp{-O} or @samp{--output-target}, or @samp{-F} or @samp{--target}
1830
1831 @item
1832 the input target (see ``@code{objcopy} and @code{strip} Input Target'' above)
1833
1834 @item
1835 environment variable @code{GNUTARGET}
1836
1837 @item
1838 deduced from the input file
1839 @end enumerate
1840
1841 @subheading @code{nm}, @code{size}, and @code{strings} Target
1842
1843 Ways to specify:
1844
1845 @enumerate
1846 @item
1847 command line option: @samp{--target}
1848
1849 @item
1850 environment variable @code{GNUTARGET}
1851
1852 @item
1853 deduced from the input file
1854 @end enumerate
1855
1856 @subheading Linker Input Target
1857
1858 Ways to specify:
1859
1860 @enumerate
1861 @item
1862 command line option: @samp{-b} or @samp{--format}
1863 (@pxref{Options,,Options,ld.info,Using LD})
1864
1865 @item
1866 script command @code{TARGET}
1867 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
1868
1869 @item
1870 environment variable @code{GNUTARGET}
1871 (@pxref{Environment,,Environment,ld.info,Using LD})
1872
1873 @item
1874 the default target of the selected linker emulation
1875 (@pxref{Linker Emulation Selection})
1876 @end enumerate
1877
1878 @subheading Linker Output Target
1879
1880 Ways to specify:
1881
1882 @enumerate
1883 @item
1884 command line option: @samp{-oformat}
1885 (@pxref{Options,,Options,ld.info,Using LD})
1886
1887 @item
1888 script command @code{OUTPUT_FORMAT}
1889 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
1890
1891 @item
1892 the linker input target (see ``Linker Input Target'' above)
1893 @end enumerate
1894
1895 @node Architecture Selection
1896 @section Architecture selection
1897
1898 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
1899 to run. Its name may contain a colon, separating the name of the
1900 processor family from the name of the particular @sc{cpu}.
1901
1902 The command to list valid architecture values is @samp{objdump -i} (the
1903 second column contains the relevant information).
1904
1905 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
1906
1907 @subheading @code{objdump} Architecture
1908
1909 Ways to specify:
1910
1911 @enumerate
1912 @item
1913 command line option: @samp{-m} or @samp{--architecture}
1914
1915 @item
1916 deduced from the input file
1917 @end enumerate
1918
1919 @subheading @code{objcopy}, @code{nm}, @code{size}, @code{strings} Architecture
1920
1921 Ways to specify:
1922
1923 @enumerate
1924 @item
1925 deduced from the input file
1926 @end enumerate
1927
1928 @subheading Linker Input Architecture
1929
1930 Ways to specify:
1931
1932 @enumerate
1933 @item
1934 deduced from the input file
1935 @end enumerate
1936
1937 @subheading Linker Output Architecture
1938
1939 Ways to specify:
1940
1941 @enumerate
1942 @item
1943 script command @code{OUTPUT_ARCH}
1944 (@pxref{Option Commands,,Option Commands,ld.info,Using LD})
1945
1946 @item
1947 the default architecture from the linker output target
1948 (@pxref{Target Selection})
1949 @end enumerate
1950
1951 @node Linker Emulation Selection
1952 @section Linker emulation selection
1953
1954 A linker @dfn{emulation} is a ``personality'' of the linker, which gives
1955 the linker default values for the other aspects of the target system.
1956 In particular, it consists of
1957
1958 @itemize @bullet
1959 @item
1960 the linker script
1961
1962 @item
1963 the target
1964
1965 @item
1966 several ``hook'' functions that are run at certain stages of the linking
1967 process to do special things that some targets require
1968 @end itemize
1969
1970 The command to list valid linker emulation values is @samp{ld -V}.
1971
1972 Sample values: @samp{hp300bsd}, @samp{mipslit}, @samp{sun4}.
1973
1974 Ways to specify:
1975
1976 @enumerate
1977 @item
1978 command line option: @samp{-m}
1979 (@pxref{Options,,Options,ld.info,Using LD})
1980
1981 @item
1982 environment variable @code{LDEMULATION}
1983
1984 @item
1985 compiled-in @code{DEFAULT_EMULATION} from @file{Makefile},
1986 which comes from @code{EMUL} in @file{config/@var{target}.mt}
1987 @end enumerate
1988
1989 @node Reporting Bugs
1990 @chapter Reporting Bugs
1991 @cindex bugs
1992 @cindex reporting bugs
1993
1994 Your bug reports play an essential role in making the binary utilities
1995 reliable.
1996
1997 Reporting a bug may help you by bringing a solution to your problem, or
1998 it may not. But in any case the principal function of a bug report is
1999 to help the entire community by making the next version of the binary
2000 utilities work better. Bug reports are your contribution to their
2001 maintenance.
2002
2003 In order for a bug report to serve its purpose, you must include the
2004 information that enables us to fix the bug.
2005
2006 @menu
2007 * Bug Criteria:: Have you found a bug?
2008 * Bug Reporting:: How to report bugs
2009 @end menu
2010
2011 @node Bug Criteria
2012 @section Have you found a bug?
2013 @cindex bug criteria
2014
2015 If you are not sure whether you have found a bug, here are some guidelines:
2016
2017 @itemize @bullet
2018 @cindex fatal signal
2019 @cindex crash
2020 @item
2021 If a binary utility gets a fatal signal, for any input whatever, that is
2022 a bug. Reliable utilities never crash.
2023
2024 @cindex error on valid input
2025 @item
2026 If a binary utility produces an error message for valid input, that is a
2027 bug.
2028
2029 @item
2030 If you are an experienced user of binary utilities, your suggestions for
2031 improvement are welcome in any case.
2032 @end itemize
2033
2034 @node Bug Reporting
2035 @section How to report bugs
2036 @cindex bug reports
2037 @cindex bugs, reporting
2038
2039 A number of companies and individuals offer support for @sc{gnu}
2040 products. If you obtained the binary utilities from a support
2041 organization, we recommend you contact that organization first.
2042
2043 You can find contact information for many support companies and
2044 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
2045 distribution.
2046
2047 In any event, we also recommend that you send bug reports for the binary
2048 utilities to @samp{bug-gnu-utils@@prep.ai.mit.edu}.
2049
2050 The fundamental principle of reporting bugs usefully is this:
2051 @strong{report all the facts}. If you are not sure whether to state a
2052 fact or leave it out, state it!
2053
2054 Often people omit facts because they think they know what causes the
2055 problem and assume that some details do not matter. Thus, you might
2056 assume that the name of a file you use in an example does not matter.
2057 Well, probably it does not, but one cannot be sure. Perhaps the bug is
2058 a stray memory reference which happens to fetch from the location where
2059 that pathname is stored in memory; perhaps, if the pathname were
2060 different, the contents of that location would fool the utility into
2061 doing the right thing despite the bug. Play it safe and give a
2062 specific, complete example. That is the easiest thing for you to do,
2063 and the most helpful.
2064
2065 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
2066 it is new to us. Therefore, always write your bug reports on the assumption
2067 that the bug has not been reported previously.
2068
2069 Sometimes people give a few sketchy facts and ask, ``Does this ring a
2070 bell?'' Those bug reports are useless, and we urge everyone to
2071 @emph{refuse to respond to them} except to chide the sender to report
2072 bugs properly.
2073
2074 To enable us to fix the bug, you should include all these things:
2075
2076 @itemize @bullet
2077 @item
2078 The version of the utility. Each utility announces it if you start it
2079 with the @samp{--version} argument.
2080
2081 Without this, we will not know whether there is any point in looking for
2082 the bug in the current version of the binary utilities.
2083
2084 @item
2085 Any patches you may have applied to the source, including any patches
2086 made to the @code{BFD} library.
2087
2088 @item
2089 The type of machine you are using, and the operating system name and
2090 version number.
2091
2092 @item
2093 What compiler (and its version) was used to compile the utilities---e.g.
2094 ``@code{gcc-2.7}''.
2095
2096 @item
2097 The command arguments you gave the utility to observe the bug. To
2098 guarantee you will not omit something important, list them all. A copy
2099 of the Makefile (or the output from make) is sufficient.
2100
2101 If we were to try to guess the arguments, we would probably guess wrong
2102 and then we might not encounter the bug.
2103
2104 @item
2105 A complete input file, or set of input files, that will reproduce the
2106 bug. If the utility is reading an object file or files, then it is
2107 generally most helpful to send the actual object files, uuencoded if
2108 necessary to get them through the mail system. Making them available
2109 for anonymous FTP is not as good, but may be the only reasonable choice
2110 for large object files.
2111
2112 If the source files were produced exclusively using @sc{gnu} programs
2113 (e.g., @code{gcc}, @code{gas}, and/or the @sc{gnu} @code{ld}), then it
2114 may be OK to send the source files rather than the object files. In
2115 this case, be sure to say exactly what version of @code{gcc}, or
2116 whatever, was used to produce the object files. Also say how
2117 @code{gcc}, or whatever, was configured.
2118
2119 @item
2120 A description of what behavior you observe that you believe is
2121 incorrect. For example, ``It gets a fatal signal.''
2122
2123 Of course, if the bug is that the utility gets a fatal signal, then we
2124 will certainly notice it. But if the bug is incorrect output, we might
2125 not notice unless it is glaringly wrong. You might as well not give us
2126 a chance to make a mistake.
2127
2128 Even if the problem you experience is a fatal signal, you should still
2129 say so explicitly. Suppose something strange is going on, such as, your
2130 copy of the utility is out of synch, or you have encountered a bug in
2131 the C library on your system. (This has happened!) Your copy might
2132 crash and ours would not. If you told us to expect a crash, then when
2133 ours fails to crash, we would know that the bug was not happening for
2134 us. If you had not told us to expect a crash, then we would not be able
2135 to draw any conclusion from our observations.
2136
2137 @item
2138 If you wish to suggest changes to the source, send us context diffs, as
2139 generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p}
2140 option. Always send diffs from the old file to the new file. If you
2141 even discuss something in the @code{ld} source, refer to it by context,
2142 not by line number.
2143
2144 The line numbers in our development sources will not match those in your
2145 sources. Your line numbers would convey no useful information to us.
2146 @end itemize
2147
2148 Here are some things that are not necessary:
2149
2150 @itemize @bullet
2151 @item
2152 A description of the envelope of the bug.
2153
2154 Often people who encounter a bug spend a lot of time investigating
2155 which changes to the input file will make the bug go away and which
2156 changes will not affect it.
2157
2158 This is often time consuming and not very useful, because the way we
2159 will find the bug is by running a single example under the debugger
2160 with breakpoints, not by pure deduction from a series of examples.
2161 We recommend that you save your time for something else.
2162
2163 Of course, if you can find a simpler example to report @emph{instead}
2164 of the original one, that is a convenience for us. Errors in the
2165 output will be easier to spot, running under the debugger will take
2166 less time, and so on.
2167
2168 However, simplification is not vital; if you do not want to do this,
2169 report the bug anyway and send us the entire test case you used.
2170
2171 @item
2172 A patch for the bug.
2173
2174 A patch for the bug does help us if it is a good one. But do not omit
2175 the necessary information, such as the test case, on the assumption that
2176 a patch is all we need. We might see problems with your patch and decide
2177 to fix the problem another way, or we might not understand it at all.
2178
2179 Sometimes with programs as complicated as the binary utilities it is
2180 very hard to construct an example that will make the program follow a
2181 certain path through the code. If you do not send us the example, we
2182 will not be able to construct one, so we will not be able to verify that
2183 the bug is fixed.
2184
2185 And if we cannot understand what bug you are trying to fix, or why your
2186 patch should be an improvement, we will not install it. A test case will
2187 help us to understand.
2188
2189 @item
2190 A guess about what the bug is or what it depends on.
2191
2192 Such guesses are usually wrong. Even we cannot guess right about such
2193 things without first using the debugger to find the facts.
2194 @end itemize
2195
2196 @node Index
2197 @unnumbered Index
2198
2199 @printindex cp
2200
2201 @contents
2202 @bye