a2768bf7e3a0935c53c13ec2446f41c34d33d18d
[binutils-gdb.git] / binutils / doc / binutils.texi
1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 @c Free Software Foundation, Inc.
5
6 @c man begin INCLUDE
7 @include bfdver.texi
8 @c man end
9
10 @ifinfo
11 @format
12 START-INFO-DIR-ENTRY
13 * Binutils: (binutils). The GNU binary utilities.
14 * ar: (binutils)ar. Create, modify, and extract from archives
15 * nm: (binutils)nm. List symbols from object files
16 * objcopy: (binutils)objcopy. Copy and translate object files
17 * objdump: (binutils)objdump. Display information from object files
18 * ranlib: (binutils)ranlib. Generate index to archive contents
19 * readelf: (binutils)readelf. Display the contents of ELF format files.
20 * size: (binutils)size. List section sizes and total size
21 * strings: (binutils)strings. List printable strings from files
22 * strip: (binutils)strip. Discard symbols
23 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
24 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
25 * addr2line: (binutils)addr2line. Convert addresses to file and line
26 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
27 * windres: (binutils)windres. Manipulate Windows resources
28 * windmc: (binutils)windmc. Generator for Windows message resources
29 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
30 END-INFO-DIR-ENTRY
31 @end format
32 @end ifinfo
33
34 @copying
35 @c man begin COPYRIGHT
36 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
37 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
38
39 Permission is granted to copy, distribute and/or modify this document
40 under the terms of the GNU Free Documentation License, Version 1.1
41 or any later version published by the Free Software Foundation;
42 with no Invariant Sections, with no Front-Cover Texts, and with no
43 Back-Cover Texts. A copy of the license is included in the
44 section entitled ``GNU Free Documentation License''.
45
46 @c man end
47 @end copying
48
49 @synindex ky cp
50 @c
51 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
52 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
53 @c
54 @c Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
55 @c 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
56 @c
57 @c This text may be freely distributed under the terms of the GNU
58 @c Free Documentation License.
59 @c
60
61 @setchapternewpage odd
62 @settitle @sc{gnu} Binary Utilities
63 @titlepage
64 @finalout
65 @title The @sc{gnu} Binary Utilities
66 @ifset VERSION_PACKAGE
67 @subtitle @value{VERSION_PACKAGE}
68 @end ifset
69 @subtitle Version @value{VERSION}
70 @sp 1
71 @subtitle @value{UPDATED}
72 @author Roland H. Pesch
73 @author Jeffrey M. Osier
74 @author Cygnus Support
75 @page
76
77 @tex
78 {\parskip=0pt \hfill Cygnus Support\par \hfill
79 \TeX{}info \texinfoversion\par }
80 @end tex
81
82 @vskip 0pt plus 1filll
83 Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
84 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
85
86 Permission is granted to copy, distribute and/or modify this document
87 under the terms of the GNU Free Documentation License, Version 1.1
88 or any later version published by the Free Software Foundation;
89 with no Invariant Sections, with no Front-Cover Texts, and with no
90 Back-Cover Texts. A copy of the license is included in the
91 section entitled ``GNU Free Documentation License''.
92
93 @end titlepage
94 @contents
95
96 @node Top
97 @top Introduction
98
99 @cindex version
100 This brief manual contains documentation for the @sc{gnu} binary
101 utilities
102 @ifset VERSION_PACKAGE
103 @value{VERSION_PACKAGE}
104 @end ifset
105 version @value{VERSION}:
106
107 @iftex
108 @table @code
109 @item ar
110 Create, modify, and extract from archives
111
112 @item nm
113 List symbols from object files
114
115 @item objcopy
116 Copy and translate object files
117
118 @item objdump
119 Display information from object files
120
121 @item ranlib
122 Generate index to archive contents
123
124 @item readelf
125 Display the contents of ELF format files.
126
127 @item size
128 List file section sizes and total size
129
130 @item strings
131 List printable strings from files
132
133 @item strip
134 Discard symbols
135
136 @item c++filt
137 Demangle encoded C++ symbols (on MS-DOS, this program is named
138 @code{cxxfilt})
139
140 @item addr2line
141 Convert addresses into file names and line numbers
142
143 @item nlmconv
144 Convert object code into a Netware Loadable Module
145
146 @item windres
147 Manipulate Windows resources
148
149 @item windmc
150 Genertor for Windows message resources
151
152 @item dlltool
153 Create the files needed to build and use Dynamic Link Libraries
154 @end table
155 @end iftex
156
157 This document is distributed under the terms of the GNU Free
158 Documentation License. A copy of the license is included in the
159 section entitled "GNU Free Documentation License".
160
161 @menu
162 * ar:: Create, modify, and extract from archives
163 * nm:: List symbols from object files
164 * objcopy:: Copy and translate object files
165 * objdump:: Display information from object files
166 * ranlib:: Generate index to archive contents
167 * readelf:: Display the contents of ELF format files.
168 * size:: List section sizes and total size
169 * strings:: List printable strings from files
170 * strip:: Discard symbols
171 * c++filt:: Filter to demangle encoded C++ symbols
172 * cxxfilt: c++filt. MS-DOS name for c++filt
173 * addr2line:: Convert addresses to file and line
174 * nlmconv:: Converts object code into an NLM
175 * windres:: Manipulate Windows resources
176 * windmc:: Generator for Windows message resources
177 * dlltool:: Create files needed to build and use DLLs
178 * Common Options:: Command-line options for all utilities
179 * Selecting The Target System:: How these utilities determine the target.
180 * Reporting Bugs:: Reporting Bugs
181 * GNU Free Documentation License:: GNU Free Documentation License
182 * Binutils Index:: Binutils Index
183 @end menu
184
185 @node ar
186 @chapter ar
187
188 @kindex ar
189 @cindex archives
190 @cindex collections of files
191
192 @c man title ar create, modify, and extract from archives
193
194 @smallexample
195 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
196 ar -M [ <mri-script ]
197 @end smallexample
198
199 @c man begin DESCRIPTION ar
200
201 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
202 archives. An @dfn{archive} is a single file holding a collection of
203 other files in a structure that makes it possible to retrieve
204 the original individual files (called @dfn{members} of the archive).
205
206 The original files' contents, mode (permissions), timestamp, owner, and
207 group are preserved in the archive, and can be restored on
208 extraction.
209
210 @cindex name length
211 @sc{gnu} @command{ar} can maintain archives whose members have names of any
212 length; however, depending on how @command{ar} is configured on your
213 system, a limit on member-name length may be imposed for compatibility
214 with archive formats maintained with other tools. If it exists, the
215 limit is often 15 characters (typical of formats related to a.out) or 16
216 characters (typical of formats related to coff).
217
218 @cindex libraries
219 @command{ar} is considered a binary utility because archives of this sort
220 are most often used as @dfn{libraries} holding commonly needed
221 subroutines.
222
223 @cindex symbol index
224 @command{ar} creates an index to the symbols defined in relocatable
225 object modules in the archive when you specify the modifier @samp{s}.
226 Once created, this index is updated in the archive whenever @command{ar}
227 makes a change to its contents (save for the @samp{q} update operation).
228 An archive with such an index speeds up linking to the library, and
229 allows routines in the library to call each other without regard to
230 their placement in the archive.
231
232 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
233 table. If an archive lacks the table, another form of @command{ar} called
234 @command{ranlib} can be used to add just the table.
235
236 @cindex compatibility, @command{ar}
237 @cindex @command{ar} compatibility
238 @sc{gnu} @command{ar} is designed to be compatible with two different
239 facilities. You can control its activity using command-line options,
240 like the different varieties of @command{ar} on Unix systems; or, if you
241 specify the single command-line option @option{-M}, you can control it
242 with a script supplied via standard input, like the MRI ``librarian''
243 program.
244
245 @c man end
246
247 @menu
248 * ar cmdline:: Controlling @command{ar} on the command line
249 * ar scripts:: Controlling @command{ar} with a script
250 @end menu
251
252 @page
253 @node ar cmdline
254 @section Controlling @command{ar} on the Command Line
255
256 @smallexample
257 @c man begin SYNOPSIS ar
258 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
259 @c man end
260 @end smallexample
261
262 @cindex Unix compatibility, @command{ar}
263 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
264 arguments to execute: one keyletter specifying the @emph{operation}
265 (optionally accompanied by other keyletters specifying
266 @emph{modifiers}), and the archive name to act on.
267
268 Most operations can also accept further @var{member} arguments,
269 specifying particular files to operate on.
270
271 @c man begin OPTIONS ar
272
273 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
274 flags @var{mod} in any order, within the first command-line argument.
275
276 If you wish, you may begin the first command-line argument with a
277 dash.
278
279 @cindex operations on archive
280 The @var{p} keyletter specifies what operation to execute; it may be
281 any of the following, but you must specify only one of them:
282
283 @table @samp
284 @item d
285 @cindex deleting from archive
286 @emph{Delete} modules from the archive. Specify the names of modules to
287 be deleted as @var{member}@dots{}; the archive is untouched if you
288 specify no files to delete.
289
290 If you specify the @samp{v} modifier, @command{ar} lists each module
291 as it is deleted.
292
293 @item m
294 @cindex moving in archive
295 Use this operation to @emph{move} members in an archive.
296
297 The ordering of members in an archive can make a difference in how
298 programs are linked using the library, if a symbol is defined in more
299 than one member.
300
301 If no modifiers are used with @code{m}, any members you name in the
302 @var{member} arguments are moved to the @emph{end} of the archive;
303 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
304 specified place instead.
305
306 @item p
307 @cindex printing from archive
308 @emph{Print} the specified members of the archive, to the standard
309 output file. If the @samp{v} modifier is specified, show the member
310 name before copying its contents to standard output.
311
312 If you specify no @var{member} arguments, all the files in the archive are
313 printed.
314
315 @item q
316 @cindex quick append to archive
317 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
318 @var{archive}, without checking for replacement.
319
320 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
321 operation; new members are always placed at the end of the archive.
322
323 The modifier @samp{v} makes @command{ar} list each file as it is appended.
324
325 Since the point of this operation is speed, the archive's symbol table
326 index is not updated, even if it already existed; you can use @samp{ar s} or
327 @command{ranlib} explicitly to update the symbol table index.
328
329 However, too many different systems assume quick append rebuilds the
330 index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
331
332 @item r
333 @cindex replacement in archive
334 Insert the files @var{member}@dots{} into @var{archive} (with
335 @emph{replacement}). This operation differs from @samp{q} in that any
336 previously existing members are deleted if their names match those being
337 added.
338
339 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
340 displays an error message, and leaves undisturbed any existing members
341 of the archive matching that name.
342
343 By default, new members are added at the end of the file; but you may
344 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
345 placement relative to some existing member.
346
347 The modifier @samp{v} used with this operation elicits a line of
348 output for each file inserted, along with one of the letters @samp{a} or
349 @samp{r} to indicate whether the file was appended (no old member
350 deleted) or replaced.
351
352 @item t
353 @cindex contents of archive
354 Display a @emph{table} listing the contents of @var{archive}, or those
355 of the files listed in @var{member}@dots{} that are present in the
356 archive. Normally only the member name is shown; if you also want to
357 see the modes (permissions), timestamp, owner, group, and size, you can
358 request that by also specifying the @samp{v} modifier.
359
360 If you do not specify a @var{member}, all files in the archive
361 are listed.
362
363 @cindex repeated names in archive
364 @cindex name duplication in archive
365 If there is more than one file with the same name (say, @samp{fie}) in
366 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
367 first instance; to see them all, you must ask for a complete
368 listing---in our example, @samp{ar t b.a}.
369 @c WRS only; per Gumby, this is implementation-dependent, and in a more
370 @c recent case in fact works the other way.
371
372 @item x
373 @cindex extract from archive
374 @emph{Extract} members (named @var{member}) from the archive. You can
375 use the @samp{v} modifier with this operation, to request that
376 @command{ar} list each name as it extracts it.
377
378 If you do not specify a @var{member}, all files in the archive
379 are extracted.
380
381 @end table
382
383 A number of modifiers (@var{mod}) may immediately follow the @var{p}
384 keyletter, to specify variations on an operation's behavior:
385
386 @table @samp
387 @item a
388 @cindex relative placement in archive
389 Add new files @emph{after} an existing member of the
390 archive. If you use the modifier @samp{a}, the name of an existing archive
391 member must be present as the @var{relpos} argument, before the
392 @var{archive} specification.
393
394 @item b
395 Add new files @emph{before} an existing member of the
396 archive. If you use the modifier @samp{b}, the name of an existing archive
397 member must be present as the @var{relpos} argument, before the
398 @var{archive} specification. (same as @samp{i}).
399
400 @item c
401 @cindex creating archives
402 @emph{Create} the archive. The specified @var{archive} is always
403 created if it did not exist, when you request an update. But a warning is
404 issued unless you specify in advance that you expect to create it, by
405 using this modifier.
406
407 @item f
408 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
409 names of any length. This will cause it to create archives which are
410 not compatible with the native @command{ar} program on some systems. If
411 this is a concern, the @samp{f} modifier may be used to truncate file
412 names when putting them in the archive.
413
414 @item i
415 Insert new files @emph{before} an existing member of the
416 archive. If you use the modifier @samp{i}, the name of an existing archive
417 member must be present as the @var{relpos} argument, before the
418 @var{archive} specification. (same as @samp{b}).
419
420 @item l
421 This modifier is accepted but not used.
422 @c whaffor ar l modifier??? presumably compat; with
423 @c what???---doc@@cygnus.com, 25jan91
424
425 @item N
426 Uses the @var{count} parameter. This is used if there are multiple
427 entries in the archive with the same name. Extract or delete instance
428 @var{count} of the given name from the archive.
429
430 @item o
431 @cindex dates in archive
432 Preserve the @emph{original} dates of members when extracting them. If
433 you do not specify this modifier, files extracted from the archive
434 are stamped with the time of extraction.
435
436 @item P
437 Use the full path name when matching names in the archive. @sc{gnu}
438 @command{ar} can not create an archive with a full path name (such archives
439 are not POSIX complaint), but other archive creators can. This option
440 will cause @sc{gnu} @command{ar} to match file names using a complete path
441 name, which can be convenient when extracting a single file from an
442 archive created by another tool.
443
444 @item s
445 @cindex writing archive index
446 Write an object-file index into the archive, or update an existing one,
447 even if no other change is made to the archive. You may use this modifier
448 flag either with any operation, or alone. Running @samp{ar s} on an
449 archive is equivalent to running @samp{ranlib} on it.
450
451 @item S
452 @cindex not writing archive index
453 Do not generate an archive symbol table. This can speed up building a
454 large library in several steps. The resulting archive can not be used
455 with the linker. In order to build a symbol table, you must omit the
456 @samp{S} modifier on the last execution of @samp{ar}, or you must run
457 @samp{ranlib} on the archive.
458
459 @item u
460 @cindex updating an archive
461 Normally, @samp{ar r}@dots{} inserts all files
462 listed into the archive. If you would like to insert @emph{only} those
463 of the files you list that are newer than existing members of the same
464 names, use this modifier. The @samp{u} modifier is allowed only for the
465 operation @samp{r} (replace). In particular, the combination @samp{qu} is
466 not allowed, since checking the timestamps would lose any speed
467 advantage from the operation @samp{q}.
468
469 @item v
470 This modifier requests the @emph{verbose} version of an operation. Many
471 operations display additional information, such as filenames processed,
472 when the modifier @samp{v} is appended.
473
474 @item V
475 This modifier shows the version number of @command{ar}.
476 @end table
477
478 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
479 compatibility with AIX. The behaviour produced by this option is the
480 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
481 @samp{-X} options; in particular, it does not support @option{-X32}
482 which is the default for AIX @command{ar}.
483
484 @c man end
485
486 @ignore
487 @c man begin SEEALSO ar
488 nm(1), ranlib(1), and the Info entries for @file{binutils}.
489 @c man end
490 @end ignore
491
492 @node ar scripts
493 @section Controlling @command{ar} with a Script
494
495 @smallexample
496 ar -M [ <@var{script} ]
497 @end smallexample
498
499 @cindex MRI compatibility, @command{ar}
500 @cindex scripts, @command{ar}
501 If you use the single command-line option @samp{-M} with @command{ar}, you
502 can control its operation with a rudimentary command language. This
503 form of @command{ar} operates interactively if standard input is coming
504 directly from a terminal. During interactive use, @command{ar} prompts for
505 input (the prompt is @samp{AR >}), and continues executing even after
506 errors. If you redirect standard input to a script file, no prompts are
507 issued, and @command{ar} abandons execution (with a nonzero exit code)
508 on any error.
509
510 The @command{ar} command language is @emph{not} designed to be equivalent
511 to the command-line options; in fact, it provides somewhat less control
512 over archives. The only purpose of the command language is to ease the
513 transition to @sc{gnu} @command{ar} for developers who already have scripts
514 written for the MRI ``librarian'' program.
515
516 The syntax for the @command{ar} command language is straightforward:
517 @itemize @bullet
518 @item
519 commands are recognized in upper or lower case; for example, @code{LIST}
520 is the same as @code{list}. In the following descriptions, commands are
521 shown in upper case for clarity.
522
523 @item
524 a single command may appear on each line; it is the first word on the
525 line.
526
527 @item
528 empty lines are allowed, and have no effect.
529
530 @item
531 comments are allowed; text after either of the characters @samp{*}
532 or @samp{;} is ignored.
533
534 @item
535 Whenever you use a list of names as part of the argument to an @command{ar}
536 command, you can separate the individual names with either commas or
537 blanks. Commas are shown in the explanations below, for clarity.
538
539 @item
540 @samp{+} is used as a line continuation character; if @samp{+} appears
541 at the end of a line, the text on the following line is considered part
542 of the current command.
543 @end itemize
544
545 Here are the commands you can use in @command{ar} scripts, or when using
546 @command{ar} interactively. Three of them have special significance:
547
548 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
549 a temporary file required for most of the other commands.
550
551 @code{SAVE} commits the changes so far specified by the script. Prior
552 to @code{SAVE}, commands affect only the temporary copy of the current
553 archive.
554
555 @table @code
556 @item ADDLIB @var{archive}
557 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
558 Add all the contents of @var{archive} (or, if specified, each named
559 @var{module} from @var{archive}) to the current archive.
560
561 Requires prior use of @code{OPEN} or @code{CREATE}.
562
563 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
564 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
565 @c else like "ar q..."
566 Add each named @var{member} as a module in the current archive.
567
568 Requires prior use of @code{OPEN} or @code{CREATE}.
569
570 @item CLEAR
571 Discard the contents of the current archive, canceling the effect of
572 any operations since the last @code{SAVE}. May be executed (with no
573 effect) even if no current archive is specified.
574
575 @item CREATE @var{archive}
576 Creates an archive, and makes it the current archive (required for many
577 other commands). The new archive is created with a temporary name; it
578 is not actually saved as @var{archive} until you use @code{SAVE}.
579 You can overwrite existing archives; similarly, the contents of any
580 existing file named @var{archive} will not be destroyed until @code{SAVE}.
581
582 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
583 Delete each listed @var{module} from the current archive; equivalent to
584 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
585
586 Requires prior use of @code{OPEN} or @code{CREATE}.
587
588 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
589 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
590 List each named @var{module} present in @var{archive}. The separate
591 command @code{VERBOSE} specifies the form of the output: when verbose
592 output is off, output is like that of @samp{ar -t @var{archive}
593 @var{module}@dots{}}. When verbose output is on, the listing is like
594 @samp{ar -tv @var{archive} @var{module}@dots{}}.
595
596 Output normally goes to the standard output stream; however, if you
597 specify @var{outputfile} as a final argument, @command{ar} directs the
598 output to that file.
599
600 @item END
601 Exit from @command{ar}, with a @code{0} exit code to indicate successful
602 completion. This command does not save the output file; if you have
603 changed the current archive since the last @code{SAVE} command, those
604 changes are lost.
605
606 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
607 Extract each named @var{module} from the current archive, writing them
608 into the current directory as separate files. Equivalent to @samp{ar -x
609 @var{archive} @var{module}@dots{}}.
610
611 Requires prior use of @code{OPEN} or @code{CREATE}.
612
613 @ignore
614 @c FIXME Tokens but no commands???
615 @item FULLDIR
616
617 @item HELP
618 @end ignore
619
620 @item LIST
621 Display full contents of the current archive, in ``verbose'' style
622 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
623 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
624 enhancement, rather than present for MRI compatibility.)
625
626 Requires prior use of @code{OPEN} or @code{CREATE}.
627
628 @item OPEN @var{archive}
629 Opens an existing archive for use as the current archive (required for
630 many other commands). Any changes as the result of subsequent commands
631 will not actually affect @var{archive} until you next use @code{SAVE}.
632
633 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
634 In the current archive, replace each existing @var{module} (named in
635 the @code{REPLACE} arguments) from files in the current working directory.
636 To execute this command without errors, both the file, and the module in
637 the current archive, must exist.
638
639 Requires prior use of @code{OPEN} or @code{CREATE}.
640
641 @item VERBOSE
642 Toggle an internal flag governing the output from @code{DIRECTORY}.
643 When the flag is on, @code{DIRECTORY} output matches output from
644 @samp{ar -tv }@dots{}.
645
646 @item SAVE
647 Commit your changes to the current archive, and actually save it as a
648 file with the name specified in the last @code{CREATE} or @code{OPEN}
649 command.
650
651 Requires prior use of @code{OPEN} or @code{CREATE}.
652
653 @end table
654
655 @iftex
656 @node ld
657 @chapter ld
658 @cindex linker
659 @kindex ld
660 The @sc{gnu} linker @command{ld} is now described in a separate manual.
661 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
662 @end iftex
663
664 @node nm
665 @chapter nm
666 @cindex symbols
667 @kindex nm
668
669 @c man title nm list symbols from object files
670
671 @smallexample
672 @c man begin SYNOPSIS nm
673 nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}]
674 [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}]
675 [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}]
676 [@option{-A}|@option{-o}|@option{--print-file-name}][@option{--special-syms}]
677 [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}]
678 [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}]
679 [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}]
680 [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}]
681 [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}]
682 [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}]
683 @c man end
684 @end smallexample
685
686 @c man begin DESCRIPTION nm
687 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
688 If no object files are listed as arguments, @command{nm} assumes the file
689 @file{a.out}.
690
691 For each symbol, @command{nm} shows:
692
693 @itemize @bullet
694 @item
695 The symbol value, in the radix selected by options (see below), or
696 hexadecimal by default.
697
698 @item
699 The symbol type. At least the following types are used; others are, as
700 well, depending on the object file format. If lowercase, the symbol is
701 local; if uppercase, the symbol is global (external).
702
703 @c Some more detail on exactly what these symbol types are used for
704 @c would be nice.
705 @table @code
706 @item A
707 The symbol's value is absolute, and will not be changed by further
708 linking.
709
710 @item B
711 The symbol is in the uninitialized data section (known as BSS).
712
713 @item C
714 The symbol is common. Common symbols are uninitialized data. When
715 linking, multiple common symbols may appear with the same name. If the
716 symbol is defined anywhere, the common symbols are treated as undefined
717 references.
718 @ifclear man
719 For more details on common symbols, see the discussion of
720 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
721 @end ifclear
722
723 @item D
724 The symbol is in the initialized data section.
725
726 @item G
727 The symbol is in an initialized data section for small objects. Some
728 object file formats permit more efficient access to small data objects,
729 such as a global int variable as opposed to a large global array.
730
731 @item I
732 The symbol is an indirect reference to another symbol. This is a @sc{gnu}
733 extension to the a.out object file format which is rarely used.
734
735 @item N
736 The symbol is a debugging symbol.
737
738 @item R
739 The symbol is in a read only data section.
740
741 @item S
742 The symbol is in an uninitialized data section for small objects.
743
744 @item T
745 The symbol is in the text (code) section.
746
747 @item U
748 The symbol is undefined.
749
750 @item V
751 The symbol is a weak object. When a weak defined symbol is linked with
752 a normal defined symbol, the normal defined symbol is used with no error.
753 When a weak undefined symbol is linked and the symbol is not defined,
754 the value of the weak symbol becomes zero with no error.
755
756 @item W
757 The symbol is a weak symbol that has not been specifically tagged as a
758 weak object symbol. When a weak defined symbol is linked with a normal
759 defined symbol, the normal defined symbol is used with no error.
760 When a weak undefined symbol is linked and the symbol is not defined,
761 the value of the symbol is determined in a system-specific manner without
762 error. On some systems, uppercase indicates that a default value has been
763 specified.
764
765
766 @item -
767 The symbol is a stabs symbol in an a.out object file. In this case, the
768 next values printed are the stabs other field, the stabs desc field, and
769 the stab type. Stabs symbols are used to hold debugging information.
770 @ifclear man
771 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
772 ``stabs'' debug format}.
773 @end ifclear
774
775 @item ?
776 The symbol type is unknown, or object file format specific.
777 @end table
778
779 @item
780 The symbol name.
781 @end itemize
782
783 @c man end
784
785 @c man begin OPTIONS nm
786 The long and short forms of options, shown here as alternatives, are
787 equivalent.
788
789 @table @env
790 @item -A
791 @itemx -o
792 @itemx --print-file-name
793 @cindex input file name
794 @cindex file name
795 @cindex source file name
796 Precede each symbol by the name of the input file (or archive member)
797 in which it was found, rather than identifying the input file once only,
798 before all of its symbols.
799
800 @item -a
801 @itemx --debug-syms
802 @cindex debugging symbols
803 Display all symbols, even debugger-only symbols; normally these are not
804 listed.
805
806 @item -B
807 @cindex @command{nm} format
808 @cindex @command{nm} compatibility
809 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
810
811 @item -C
812 @itemx --demangle[=@var{style}]
813 @cindex demangling in nm
814 Decode (@dfn{demangle}) low-level symbol names into user-level names.
815 Besides removing any initial underscore prepended by the system, this
816 makes C++ function names readable. Different compilers have different
817 mangling styles. The optional demangling style argument can be used to
818 choose an appropriate demangling style for your compiler. @xref{c++filt},
819 for more information on demangling.
820
821 @item --no-demangle
822 Do not demangle low-level symbol names. This is the default.
823
824 @item -D
825 @itemx --dynamic
826 @cindex dynamic symbols
827 Display the dynamic symbols rather than the normal symbols. This is
828 only meaningful for dynamic objects, such as certain types of shared
829 libraries.
830
831 @item -f @var{format}
832 @itemx --format=@var{format}
833 @cindex @command{nm} format
834 @cindex @command{nm} compatibility
835 Use the output format @var{format}, which can be @code{bsd},
836 @code{sysv}, or @code{posix}. The default is @code{bsd}.
837 Only the first character of @var{format} is significant; it can be
838 either upper or lower case.
839
840 @item -g
841 @itemx --extern-only
842 @cindex external symbols
843 Display only external symbols.
844
845 @item -l
846 @itemx --line-numbers
847 @cindex symbol line numbers
848 For each symbol, use debugging information to try to find a filename and
849 line number. For a defined symbol, look for the line number of the
850 address of the symbol. For an undefined symbol, look for the line
851 number of a relocation entry which refers to the symbol. If line number
852 information can be found, print it after the other symbol information.
853
854 @item -n
855 @itemx -v
856 @itemx --numeric-sort
857 Sort symbols numerically by their addresses, rather than alphabetically
858 by their names.
859
860 @item -p
861 @itemx --no-sort
862 @cindex sorting symbols
863 Do not bother to sort the symbols in any order; print them in the order
864 encountered.
865
866 @item -P
867 @itemx --portability
868 Use the POSIX.2 standard output format instead of the default format.
869 Equivalent to @samp{-f posix}.
870
871 @item -S
872 @itemx --print-size
873 Print size, not the value, of defined symbols for the @code{bsd} output format.
874
875 @item -s
876 @itemx --print-armap
877 @cindex symbol index, listing
878 When listing symbols from archive members, include the index: a mapping
879 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
880 contain definitions for which names.
881
882 @item -r
883 @itemx --reverse-sort
884 Reverse the order of the sort (whether numeric or alphabetic); let the
885 last come first.
886
887 @item --size-sort
888 Sort symbols by size. The size is computed as the difference between
889 the value of the symbol and the value of the symbol with the next higher
890 value. If the @code{bsd} output format is used the size of the symbol
891 is printed, rather than the value, and @samp{-S} must be used in order
892 both size and value to be printed.
893
894 @item --special-syms
895 Display symbols which have a target-specific special meaning. These
896 symbols are usually used by the target for some special processing and
897 are not normally helpful when included included in the normal symbol
898 lists. For example for ARM targets this option would skip the mapping
899 symbols used to mark transitions between ARM code, THUMB code and
900 data.
901
902 @item -t @var{radix}
903 @itemx --radix=@var{radix}
904 Use @var{radix} as the radix for printing the symbol values. It must be
905 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
906
907 @item --target=@var{bfdname}
908 @cindex object code format
909 Specify an object code format other than your system's default format.
910 @xref{Target Selection}, for more information.
911
912 @item -u
913 @itemx --undefined-only
914 @cindex external symbols
915 @cindex undefined symbols
916 Display only undefined symbols (those external to each object file).
917
918 @item --defined-only
919 @cindex external symbols
920 @cindex undefined symbols
921 Display only defined symbols for each object file.
922
923 @item -V
924 @itemx --version
925 Show the version number of @command{nm} and exit.
926
927 @item -X
928 This option is ignored for compatibility with the AIX version of
929 @command{nm}. It takes one parameter which must be the string
930 @option{32_64}. The default mode of AIX @command{nm} corresponds
931 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
932
933 @item --help
934 Show a summary of the options to @command{nm} and exit.
935 @end table
936
937 @c man end
938
939 @ignore
940 @c man begin SEEALSO nm
941 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
942 @c man end
943 @end ignore
944
945 @node objcopy
946 @chapter objcopy
947
948 @c man title objcopy copy and translate object files
949
950 @smallexample
951 @c man begin SYNOPSIS objcopy
952 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
953 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
954 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
955 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
956 [@option{-S}|@option{--strip-all}]
957 [@option{-g}|@option{--strip-debug}]
958 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
959 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
960 [@option{--strip-unneeded-symbol=}@var{symbolname}]
961 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
962 [@option{--localize-hidden}]
963 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
964 [@option{--globalize-symbol=}@var{symbolname}]
965 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
966 [@option{-w}|@option{--wildcard}]
967 [@option{-x}|@option{--discard-all}]
968 [@option{-X}|@option{--discard-locals}]
969 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
970 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
971 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
972 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
973 [@option{-p}|@option{--preserve-dates}]
974 [@option{--debugging}]
975 [@option{--gap-fill=}@var{val}]
976 [@option{--pad-to=}@var{address}]
977 [@option{--set-start=}@var{val}]
978 [@option{--adjust-start=}@var{incr}]
979 [@option{--change-addresses=}@var{incr}]
980 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
981 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
982 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
983 [@option{--change-warnings}] [@option{--no-change-warnings}]
984 [@option{--set-section-flags} @var{section}=@var{flags}]
985 [@option{--add-section} @var{sectionname}=@var{filename}]
986 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
987 [@option{--change-leading-char}] [@option{--remove-leading-char}]
988 [@option{--reverse-bytes=}@var{num}]
989 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
990 [@option{--redefine-sym} @var{old}=@var{new}]
991 [@option{--redefine-syms=}@var{filename}]
992 [@option{--weaken}]
993 [@option{--keep-symbols=}@var{filename}]
994 [@option{--strip-symbols=}@var{filename}]
995 [@option{--strip-unneeded-symbols=}@var{filename}]
996 [@option{--keep-global-symbols=}@var{filename}]
997 [@option{--localize-symbols=}@var{filename}]
998 [@option{--globalize-symbols=}@var{filename}]
999 [@option{--weaken-symbols=}@var{filename}]
1000 [@option{--alt-machine-code=}@var{index}]
1001 [@option{--prefix-symbols=}@var{string}]
1002 [@option{--prefix-sections=}@var{string}]
1003 [@option{--prefix-alloc-sections=}@var{string}]
1004 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1005 [@option{--keep-file-symbols}]
1006 [@option{--only-keep-debug}]
1007 [@option{--extract-symbol}]
1008 [@option{--writable-text}]
1009 [@option{--readonly-text}]
1010 [@option{--pure}]
1011 [@option{--impure}]
1012 [@option{-v}|@option{--verbose}]
1013 [@option{-V}|@option{--version}]
1014 [@option{--help}] [@option{--info}]
1015 @var{infile} [@var{outfile}]
1016 @c man end
1017 @end smallexample
1018
1019 @c man begin DESCRIPTION objcopy
1020 The @sc{gnu} @command{objcopy} utility copies the contents of an object
1021 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1022 read and write the object files. It can write the destination object
1023 file in a format different from that of the source object file. The
1024 exact behavior of @command{objcopy} is controlled by command-line options.
1025 Note that @command{objcopy} should be able to copy a fully linked file
1026 between any two formats. However, copying a relocatable object file
1027 between any two formats may not work as expected.
1028
1029 @command{objcopy} creates temporary files to do its translations and
1030 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1031 translation work; it has access to all the formats described in @sc{bfd}
1032 and thus is able to recognize most formats without being told
1033 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1034
1035 @command{objcopy} can be used to generate S-records by using an output
1036 target of @samp{srec} (e.g., use @samp{-O srec}).
1037
1038 @command{objcopy} can be used to generate a raw binary file by using an
1039 output target of @samp{binary} (e.g., use @option{-O binary}). When
1040 @command{objcopy} generates a raw binary file, it will essentially produce
1041 a memory dump of the contents of the input object file. All symbols and
1042 relocation information will be discarded. The memory dump will start at
1043 the load address of the lowest section copied into the output file.
1044
1045 When generating an S-record or a raw binary file, it may be helpful to
1046 use @option{-S} to remove sections containing debugging information. In
1047 some cases @option{-R} will be useful to remove sections which contain
1048 information that is not needed by the binary file.
1049
1050 Note---@command{objcopy} is not able to change the endianness of its input
1051 files. If the input format has an endianness (some formats do not),
1052 @command{objcopy} can only copy the inputs into file formats that have the
1053 same endianness or which have no endianness (e.g., @samp{srec}).
1054 (However, see the @option{--reverse-bytes} option.)
1055
1056 @c man end
1057
1058 @c man begin OPTIONS objcopy
1059
1060 @table @env
1061 @item @var{infile}
1062 @itemx @var{outfile}
1063 The input and output files, respectively.
1064 If you do not specify @var{outfile}, @command{objcopy} creates a
1065 temporary file and destructively renames the result with
1066 the name of @var{infile}.
1067
1068 @item -I @var{bfdname}
1069 @itemx --input-target=@var{bfdname}
1070 Consider the source file's object format to be @var{bfdname}, rather than
1071 attempting to deduce it. @xref{Target Selection}, for more information.
1072
1073 @item -O @var{bfdname}
1074 @itemx --output-target=@var{bfdname}
1075 Write the output file using the object format @var{bfdname}.
1076 @xref{Target Selection}, for more information.
1077
1078 @item -F @var{bfdname}
1079 @itemx --target=@var{bfdname}
1080 Use @var{bfdname} as the object format for both the input and the output
1081 file; i.e., simply transfer data from source to destination with no
1082 translation. @xref{Target Selection}, for more information.
1083
1084 @item -B @var{bfdarch}
1085 @itemx --binary-architecture=@var{bfdarch}
1086 Useful when transforming a raw binary input file into an object file.
1087 In this case the output architecture can be set to @var{bfdarch}. This
1088 option will be ignored if the input file has a known @var{bfdarch}. You
1089 can access this binary data inside a program by referencing the special
1090 symbols that are created by the conversion process. These symbols are
1091 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1092 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1093 an object file and then access it in your code using these symbols.
1094
1095 @item -j @var{sectionname}
1096 @itemx --only-section=@var{sectionname}
1097 Copy only the named section from the input file to the output file.
1098 This option may be given more than once. Note that using this option
1099 inappropriately may make the output file unusable.
1100
1101 @item -R @var{sectionname}
1102 @itemx --remove-section=@var{sectionname}
1103 Remove any section named @var{sectionname} from the output file. This
1104 option may be given more than once. Note that using this option
1105 inappropriately may make the output file unusable.
1106
1107 @item -S
1108 @itemx --strip-all
1109 Do not copy relocation and symbol information from the source file.
1110
1111 @item -g
1112 @itemx --strip-debug
1113 Do not copy debugging symbols or sections from the source file.
1114
1115 @item --strip-unneeded
1116 Strip all symbols that are not needed for relocation processing.
1117
1118 @item -K @var{symbolname}
1119 @itemx --keep-symbol=@var{symbolname}
1120 When stripping symbols, keep symbol @var{symbolname} even if it would
1121 normally be stripped. This option may be given more than once.
1122
1123 @item -N @var{symbolname}
1124 @itemx --strip-symbol=@var{symbolname}
1125 Do not copy symbol @var{symbolname} from the source file. This option
1126 may be given more than once.
1127
1128 @item --strip-unneeded-symbol=@var{symbolname}
1129 Do not copy symbol @var{symbolname} from the source file unless it is needed
1130 by a relocation. This option may be given more than once.
1131
1132 @item -G @var{symbolname}
1133 @itemx --keep-global-symbol=@var{symbolname}
1134 Keep only symbol @var{symbolname} global. Make all other symbols local
1135 to the file, so that they are not visible externally. This option may
1136 be given more than once.
1137
1138 @item --localize-hidden
1139 In an ELF object, mark all symbols that have hidden or internal visibility
1140 as local. This option applies on top of symbol-specific localization options
1141 such as @option{-L}.
1142
1143 @item -L @var{symbolname}
1144 @itemx --localize-symbol=@var{symbolname}
1145 Make symbol @var{symbolname} local to the file, so that it is not
1146 visible externally. This option may be given more than once.
1147
1148 @item -W @var{symbolname}
1149 @itemx --weaken-symbol=@var{symbolname}
1150 Make symbol @var{symbolname} weak. This option may be given more than once.
1151
1152 @item --globalize-symbol=@var{symbolname}
1153 Give symbol @var{symbolname} global scoping so that it is visible
1154 outside of the file in which it is defined. This option may be given
1155 more than once.
1156
1157 @item -w
1158 @itemx --wildcard
1159 Permit regular expressions in @var{symbolname}s used in other command
1160 line options. The question mark (?), asterisk (*), backslash (\) and
1161 square brackets ([]) operators can be used anywhere in the symbol
1162 name. If the first character of the symbol name is the exclamation
1163 point (!) then the sense of the switch is reversed for that symbol.
1164 For example:
1165
1166 @smallexample
1167 -w -W !foo -W fo*
1168 @end smallexample
1169
1170 would cause objcopy to weaken all symbols that start with ``fo''
1171 except for the symbol ``foo''.
1172
1173 @item -x
1174 @itemx --discard-all
1175 Do not copy non-global symbols from the source file.
1176 @c FIXME any reason to prefer "non-global" to "local" here?
1177
1178 @item -X
1179 @itemx --discard-locals
1180 Do not copy compiler-generated local symbols.
1181 (These usually start with @samp{L} or @samp{.}.)
1182
1183 @item -b @var{byte}
1184 @itemx --byte=@var{byte}
1185 Keep only every @var{byte}th byte of the input file (header data is not
1186 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1187 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1188 option, or the default of 4. This option is useful for creating files
1189 to program @sc{rom}. It is typically used with an @code{srec} output
1190 target.
1191
1192 @item -i @var{interleave}
1193 @itemx --interleave=@var{interleave}
1194 Only copy one out of every @var{interleave} bytes. Select which byte to
1195 copy with the @option{-b} or @option{--byte} option. The default is 4.
1196 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1197 @option{--byte}.
1198
1199 @item -p
1200 @itemx --preserve-dates
1201 Set the access and modification dates of the output file to be the same
1202 as those of the input file.
1203
1204 @item --debugging
1205 Convert debugging information, if possible. This is not the default
1206 because only certain debugging formats are supported, and the
1207 conversion process can be time consuming.
1208
1209 @item --gap-fill @var{val}
1210 Fill gaps between sections with @var{val}. This operation applies to
1211 the @emph{load address} (LMA) of the sections. It is done by increasing
1212 the size of the section with the lower address, and filling in the extra
1213 space created with @var{val}.
1214
1215 @item --pad-to @var{address}
1216 Pad the output file up to the load address @var{address}. This is
1217 done by increasing the size of the last section. The extra space is
1218 filled in with the value specified by @option{--gap-fill} (default zero).
1219
1220 @item --set-start @var{val}
1221 Set the start address of the new file to @var{val}. Not all object file
1222 formats support setting the start address.
1223
1224 @item --change-start @var{incr}
1225 @itemx --adjust-start @var{incr}
1226 @cindex changing start address
1227 Change the start address by adding @var{incr}. Not all object file
1228 formats support setting the start address.
1229
1230 @item --change-addresses @var{incr}
1231 @itemx --adjust-vma @var{incr}
1232 @cindex changing object addresses
1233 Change the VMA and LMA addresses of all sections, as well as the start
1234 address, by adding @var{incr}. Some object file formats do not permit
1235 section addresses to be changed arbitrarily. Note that this does not
1236 relocate the sections; if the program expects sections to be loaded at a
1237 certain address, and this option is used to change the sections such
1238 that they are loaded at a different address, the program may fail.
1239
1240 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1241 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1242 @cindex changing section address
1243 Set or change both the VMA address and the LMA address of the named
1244 @var{section}. If @samp{=} is used, the section address is set to
1245 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1246 section address. See the comments under @option{--change-addresses},
1247 above. If @var{section} does not exist in the input file, a warning will
1248 be issued, unless @option{--no-change-warnings} is used.
1249
1250 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1251 @cindex changing section LMA
1252 Set or change the LMA address of the named @var{section}. The LMA
1253 address is the address where the section will be loaded into memory at
1254 program load time. Normally this is the same as the VMA address, which
1255 is the address of the section at program run time, but on some systems,
1256 especially those where a program is held in ROM, the two can be
1257 different. If @samp{=} is used, the section address is set to
1258 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1259 section address. See the comments under @option{--change-addresses},
1260 above. If @var{section} does not exist in the input file, a warning
1261 will be issued, unless @option{--no-change-warnings} is used.
1262
1263 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1264 @cindex changing section VMA
1265 Set or change the VMA address of the named @var{section}. The VMA
1266 address is the address where the section will be located once the
1267 program has started executing. Normally this is the same as the LMA
1268 address, which is the address where the section will be loaded into
1269 memory, but on some systems, especially those where a program is held in
1270 ROM, the two can be different. If @samp{=} is used, the section address
1271 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1272 from the section address. See the comments under
1273 @option{--change-addresses}, above. If @var{section} does not exist in
1274 the input file, a warning will be issued, unless
1275 @option{--no-change-warnings} is used.
1276
1277 @item --change-warnings
1278 @itemx --adjust-warnings
1279 If @option{--change-section-address} or @option{--change-section-lma} or
1280 @option{--change-section-vma} is used, and the named section does not
1281 exist, issue a warning. This is the default.
1282
1283 @item --no-change-warnings
1284 @itemx --no-adjust-warnings
1285 Do not issue a warning if @option{--change-section-address} or
1286 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1287 if the named section does not exist.
1288
1289 @item --set-section-flags @var{section}=@var{flags}
1290 Set the flags for the named section. The @var{flags} argument is a
1291 comma separated string of flag names. The recognized names are
1292 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1293 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1294 @samp{debug}. You can set the @samp{contents} flag for a section which
1295 does not have contents, but it is not meaningful to clear the
1296 @samp{contents} flag of a section which does have contents--just remove
1297 the section instead. Not all flags are meaningful for all object file
1298 formats.
1299
1300 @item --add-section @var{sectionname}=@var{filename}
1301 Add a new section named @var{sectionname} while copying the file. The
1302 contents of the new section are taken from the file @var{filename}. The
1303 size of the section will be the size of the file. This option only
1304 works on file formats which can support sections with arbitrary names.
1305
1306 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1307 Rename a section from @var{oldname} to @var{newname}, optionally
1308 changing the section's flags to @var{flags} in the process. This has
1309 the advantage over usng a linker script to perform the rename in that
1310 the output stays as an object file and does not become a linked
1311 executable.
1312
1313 This option is particularly helpful when the input format is binary,
1314 since this will always create a section called .data. If for example,
1315 you wanted instead to create a section called .rodata containing binary
1316 data you could use the following command line to achieve it:
1317
1318 @smallexample
1319 objcopy -I binary -O <output_format> -B <architecture> \
1320 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1321 <input_binary_file> <output_object_file>
1322 @end smallexample
1323
1324 @item --change-leading-char
1325 Some object file formats use special characters at the start of
1326 symbols. The most common such character is underscore, which compilers
1327 often add before every symbol. This option tells @command{objcopy} to
1328 change the leading character of every symbol when it converts between
1329 object file formats. If the object file formats use the same leading
1330 character, this option has no effect. Otherwise, it will add a
1331 character, or remove a character, or change a character, as
1332 appropriate.
1333
1334 @item --remove-leading-char
1335 If the first character of a global symbol is a special symbol leading
1336 character used by the object file format, remove the character. The
1337 most common symbol leading character is underscore. This option will
1338 remove a leading underscore from all global symbols. This can be useful
1339 if you want to link together objects of different file formats with
1340 different conventions for symbol names. This is different from
1341 @option{--change-leading-char} because it always changes the symbol name
1342 when appropriate, regardless of the object file format of the output
1343 file.
1344
1345 @item --reverse-bytes=@var{num}
1346 Reverse the bytes in a section with output contents. A section length must
1347 be evenly divisible by the value given in order for the swap to be able to
1348 take place. Reversing takes place before the interleaving is performed.
1349
1350 This option is used typically in generating ROM images for problematic
1351 target systems. For example, on some target boards, the 32-bit words
1352 fetched from 8-bit ROMs are re-assembled in little-endian byte order
1353 regardless of the CPU byte order. Depending on the programming model, the
1354 endianness of the ROM may need to be modified.
1355
1356 Consider a simple file with a section containing the following eight
1357 bytes: @code{12345678}.
1358
1359 Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1360 output file would be ordered @code{21436587}.
1361
1362 Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1363 output file would be ordered @code{43218765}.
1364
1365 By using @samp{--reverse-bytes=2} for the above example, followed by
1366 @samp{--reverse-bytes=4} on the output file, the bytes in the second
1367 output file would be ordered @code{34127856}.
1368
1369 @item --srec-len=@var{ival}
1370 Meaningful only for srec output. Set the maximum length of the Srecords
1371 being produced to @var{ival}. This length covers both address, data and
1372 crc fields.
1373
1374 @item --srec-forceS3
1375 Meaningful only for srec output. Avoid generation of S1/S2 records,
1376 creating S3-only record format.
1377
1378 @item --redefine-sym @var{old}=@var{new}
1379 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1380 when one is trying link two things together for which you have no
1381 source, and there are name collisions.
1382
1383 @item --redefine-syms=@var{filename}
1384 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1385 listed in the file @var{filename}. @var{filename} is simply a flat file,
1386 with one symbol pair per line. Line comments may be introduced by the hash
1387 character. This option may be given more than once.
1388
1389 @item --weaken
1390 Change all global symbols in the file to be weak. This can be useful
1391 when building an object which will be linked against other objects using
1392 the @option{-R} option to the linker. This option is only effective when
1393 using an object file format which supports weak symbols.
1394
1395 @item --keep-symbols=@var{filename}
1396 Apply @option{--keep-symbol} option to each symbol listed in the file
1397 @var{filename}. @var{filename} is simply a flat file, with one symbol
1398 name per line. Line comments may be introduced by the hash character.
1399 This option may be given more than once.
1400
1401 @item --strip-symbols=@var{filename}
1402 Apply @option{--strip-symbol} option to each symbol listed in the file
1403 @var{filename}. @var{filename} is simply a flat file, with one symbol
1404 name per line. Line comments may be introduced by the hash character.
1405 This option may be given more than once.
1406
1407 @item --strip-unneeded-symbols=@var{filename}
1408 Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1409 the file @var{filename}. @var{filename} is simply a flat file, with one
1410 symbol name per line. Line comments may be introduced by the hash
1411 character. This option may be given more than once.
1412
1413 @item --keep-global-symbols=@var{filename}
1414 Apply @option{--keep-global-symbol} option to each symbol listed in the
1415 file @var{filename}. @var{filename} is simply a flat file, with one
1416 symbol name per line. Line comments may be introduced by the hash
1417 character. This option may be given more than once.
1418
1419 @item --localize-symbols=@var{filename}
1420 Apply @option{--localize-symbol} option to each symbol listed in the file
1421 @var{filename}. @var{filename} is simply a flat file, with one symbol
1422 name per line. Line comments may be introduced by the hash character.
1423 This option may be given more than once.
1424
1425 @item --globalize-symbols=@var{filename}
1426 Apply @option{--globalize-symbol} option to each symbol listed in the file
1427 @var{filename}. @var{filename} is simply a flat file, with one symbol
1428 name per line. Line comments may be introduced by the hash character.
1429 This option may be given more than once.
1430
1431 @item --weaken-symbols=@var{filename}
1432 Apply @option{--weaken-symbol} option to each symbol listed in the file
1433 @var{filename}. @var{filename} is simply a flat file, with one symbol
1434 name per line. Line comments may be introduced by the hash character.
1435 This option may be given more than once.
1436
1437 @item --alt-machine-code=@var{index}
1438 If the output architecture has alternate machine codes, use the
1439 @var{index}th code instead of the default one. This is useful in case
1440 a machine is assigned an official code and the tool-chain adopts the
1441 new code, but other applications still depend on the original code
1442 being used. For ELF based architectures if the @var{index}
1443 alternative does not exist then the value is treated as an absolute
1444 number to be stored in the e_machine field of the ELF header.
1445
1446 @item --writable-text
1447 Mark the output text as writable. This option isn't meaningful for all
1448 object file formats.
1449
1450 @item --readonly-text
1451 Make the output text write protected. This option isn't meaningful for all
1452 object file formats.
1453
1454 @item --pure
1455 Mark the output file as demand paged. This option isn't meaningful for all
1456 object file formats.
1457
1458 @item --impure
1459 Mark the output file as impure. This option isn't meaningful for all
1460 object file formats.
1461
1462 @item --prefix-symbols=@var{string}
1463 Prefix all symbols in the output file with @var{string}.
1464
1465 @item --prefix-sections=@var{string}
1466 Prefix all section names in the output file with @var{string}.
1467
1468 @item --prefix-alloc-sections=@var{string}
1469 Prefix all the names of all allocated sections in the output file with
1470 @var{string}.
1471
1472 @item --add-gnu-debuglink=@var{path-to-file}
1473 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1474 and adds it to the output file.
1475
1476 @item --keep-file-symbols
1477 When stripping a file, perhaps with @option{--strip-debug} or
1478 @option{--strip-unneeded}, retain any symbols specifying source file names,
1479 which would otherwise get stripped.
1480
1481 @item --only-keep-debug
1482 Strip a file, removing contents of any sections that would not be
1483 stripped by @option{--strip-debug} and leaving the debugging sections
1484 intact. In ELF files, this preserves all note sections in the output.
1485
1486 The intention is that this option will be used in conjunction with
1487 @option{--add-gnu-debuglink} to create a two part executable. One a
1488 stripped binary which will occupy less space in RAM and in a
1489 distribution and the second a debugging information file which is only
1490 needed if debugging abilities are required. The suggested procedure
1491 to create these files is as follows:
1492
1493 @enumerate
1494 @item Link the executable as normal. Assuming that is is called
1495 @code{foo} then...
1496 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1497 create a file containing the debugging info.
1498 @item Run @code{objcopy --strip-debug foo} to create a
1499 stripped executable.
1500 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1501 to add a link to the debugging info into the stripped executable.
1502 @end enumerate
1503
1504 Note - the choice of @code{.dbg} as an extension for the debug info
1505 file is arbitrary. Also the @code{--only-keep-debug} step is
1506 optional. You could instead do this:
1507
1508 @enumerate
1509 @item Link the executable as normal.
1510 @item Copy @code{foo} to @code{foo.full}
1511 @item Run @code{objcopy --strip-debug foo}
1512 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1513 @end enumerate
1514
1515 i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1516 full executable. It does not have to be a file created by the
1517 @option{--only-keep-debug} switch.
1518
1519 Note - this switch is only intended for use on fully linked files. It
1520 does not make sense to use it on object files where the debugging
1521 information may be incomplete. Besides the gnu_debuglink feature
1522 currently only supports the presence of one filename containing
1523 debugging information, not multiple filenames on a one-per-object-file
1524 basis.
1525
1526 @item --extract-symbol
1527 Keep the file's section flags and symbols but remove all section data.
1528 Specifically, the option:
1529
1530 @itemize
1531 @item sets the virtual and load addresses of every section to zero;
1532 @item removes the contents of all sections;
1533 @item sets the size of every section to zero; and
1534 @item sets the file's start address to zero.
1535 @end itemize
1536
1537 This option is used to build a @file{.sym} file for a VxWorks kernel.
1538 It can also be a useful way of reducing the size of a @option{--just-symbols}
1539 linker input file.
1540
1541 @item -V
1542 @itemx --version
1543 Show the version number of @command{objcopy}.
1544
1545 @item -v
1546 @itemx --verbose
1547 Verbose output: list all object files modified. In the case of
1548 archives, @samp{objcopy -V} lists all members of the archive.
1549
1550 @item --help
1551 Show a summary of the options to @command{objcopy}.
1552
1553 @item --info
1554 Display a list showing all architectures and object formats available.
1555 @end table
1556
1557 @c man end
1558
1559 @ignore
1560 @c man begin SEEALSO objcopy
1561 ld(1), objdump(1), and the Info entries for @file{binutils}.
1562 @c man end
1563 @end ignore
1564
1565 @node objdump
1566 @chapter objdump
1567
1568 @cindex object file information
1569 @kindex objdump
1570
1571 @c man title objdump display information from object files.
1572
1573 @smallexample
1574 @c man begin SYNOPSIS objdump
1575 objdump [@option{-a}|@option{--archive-headers}]
1576 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1577 [@option{-C}|@option{--demangle}[=@var{style}] ]
1578 [@option{-d}|@option{--disassemble}]
1579 [@option{-D}|@option{--disassemble-all}]
1580 [@option{-z}|@option{--disassemble-zeroes}]
1581 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1582 [@option{-f}|@option{--file-headers}]
1583 [@option{--file-start-context}]
1584 [@option{-g}|@option{--debugging}]
1585 [@option{-e}|@option{--debugging-tags}]
1586 [@option{-h}|@option{--section-headers}|@option{--headers}]
1587 [@option{-i}|@option{--info}]
1588 [@option{-j} @var{section}|@option{--section=}@var{section}]
1589 [@option{-l}|@option{--line-numbers}]
1590 [@option{-S}|@option{--source}]
1591 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1592 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1593 [@option{-p}|@option{--private-headers}]
1594 [@option{-r}|@option{--reloc}]
1595 [@option{-R}|@option{--dynamic-reloc}]
1596 [@option{-s}|@option{--full-contents}]
1597 [@option{-W}|@option{--dwarf}]
1598 [@option{-G}|@option{--stabs}]
1599 [@option{-t}|@option{--syms}]
1600 [@option{-T}|@option{--dynamic-syms}]
1601 [@option{-x}|@option{--all-headers}]
1602 [@option{-w}|@option{--wide}]
1603 [@option{--start-address=}@var{address}]
1604 [@option{--stop-address=}@var{address}]
1605 [@option{--prefix-addresses}]
1606 [@option{--[no-]show-raw-insn}]
1607 [@option{--adjust-vma=}@var{offset}]
1608 [@option{--special-syms}]
1609 [@option{-V}|@option{--version}]
1610 [@option{-H}|@option{--help}]
1611 @var{objfile}@dots{}
1612 @c man end
1613 @end smallexample
1614
1615 @c man begin DESCRIPTION objdump
1616
1617 @command{objdump} displays information about one or more object files.
1618 The options control what particular information to display. This
1619 information is mostly useful to programmers who are working on the
1620 compilation tools, as opposed to programmers who just want their
1621 program to compile and work.
1622
1623 @var{objfile}@dots{} are the object files to be examined. When you
1624 specify archives, @command{objdump} shows information on each of the member
1625 object files.
1626
1627 @c man end
1628
1629 @c man begin OPTIONS objdump
1630
1631 The long and short forms of options, shown here as alternatives, are
1632 equivalent. At least one option from the list
1633 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1634
1635 @table @env
1636 @item -a
1637 @itemx --archive-header
1638 @cindex archive headers
1639 If any of the @var{objfile} files are archives, display the archive
1640 header information (in a format similar to @samp{ls -l}). Besides the
1641 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1642 the object file format of each archive member.
1643
1644 @item --adjust-vma=@var{offset}
1645 @cindex section addresses in objdump
1646 @cindex VMA in objdump
1647 When dumping information, first add @var{offset} to all the section
1648 addresses. This is useful if the section addresses do not correspond to
1649 the symbol table, which can happen when putting sections at particular
1650 addresses when using a format which can not represent section addresses,
1651 such as a.out.
1652
1653 @item -b @var{bfdname}
1654 @itemx --target=@var{bfdname}
1655 @cindex object code format
1656 Specify that the object-code format for the object files is
1657 @var{bfdname}. This option may not be necessary; @var{objdump} can
1658 automatically recognize many formats.
1659
1660 For example,
1661 @example
1662 objdump -b oasys -m vax -h fu.o
1663 @end example
1664 @noindent
1665 displays summary information from the section headers (@option{-h}) of
1666 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1667 file in the format produced by Oasys compilers. You can list the
1668 formats available with the @option{-i} option.
1669 @xref{Target Selection}, for more information.
1670
1671 @item -C
1672 @itemx --demangle[=@var{style}]
1673 @cindex demangling in objdump
1674 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1675 Besides removing any initial underscore prepended by the system, this
1676 makes C++ function names readable. Different compilers have different
1677 mangling styles. The optional demangling style argument can be used to
1678 choose an appropriate demangling style for your compiler. @xref{c++filt},
1679 for more information on demangling.
1680
1681 @item -g
1682 @itemx --debugging
1683 Display debugging information. This attempts to parse debugging
1684 information stored in the file and print it out using a C like syntax.
1685 Only certain types of debugging information have been implemented.
1686 Some other types are supported by @command{readelf -w}.
1687 @xref{readelf}.
1688
1689 @item -e
1690 @itemx --debugging-tags
1691 Like @option{-g}, but the information is generated in a format compatible
1692 with ctags tool.
1693
1694 @item -d
1695 @itemx --disassemble
1696 @cindex disassembling object code
1697 @cindex machine instructions
1698 Display the assembler mnemonics for the machine instructions from
1699 @var{objfile}. This option only disassembles those sections which are
1700 expected to contain instructions.
1701
1702 @item -D
1703 @itemx --disassemble-all
1704 Like @option{-d}, but disassemble the contents of all sections, not just
1705 those expected to contain instructions.
1706
1707 @item --prefix-addresses
1708 When disassembling, print the complete address on each line. This is
1709 the older disassembly format.
1710
1711 @item -EB
1712 @itemx -EL
1713 @itemx --endian=@{big|little@}
1714 @cindex endianness
1715 @cindex disassembly endianness
1716 Specify the endianness of the object files. This only affects
1717 disassembly. This can be useful when disassembling a file format which
1718 does not describe endianness information, such as S-records.
1719
1720 @item -f
1721 @itemx --file-headers
1722 @cindex object file header
1723 Display summary information from the overall header of
1724 each of the @var{objfile} files.
1725
1726 @item --file-start-context
1727 @cindex source code context
1728 Specify that when displaying interlisted source code/disassembly
1729 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1730 context to the start of the file.
1731
1732 @item -h
1733 @itemx --section-headers
1734 @itemx --headers
1735 @cindex section headers
1736 Display summary information from the section headers of the
1737 object file.
1738
1739 File segments may be relocated to nonstandard addresses, for example by
1740 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1741 @command{ld}. However, some object file formats, such as a.out, do not
1742 store the starting address of the file segments. In those situations,
1743 although @command{ld} relocates the sections correctly, using @samp{objdump
1744 -h} to list the file section headers cannot show the correct addresses.
1745 Instead, it shows the usual addresses, which are implicit for the
1746 target.
1747
1748 @item -H
1749 @itemx --help
1750 Print a summary of the options to @command{objdump} and exit.
1751
1752 @item -i
1753 @itemx --info
1754 @cindex architectures available
1755 @cindex object formats available
1756 Display a list showing all architectures and object formats available
1757 for specification with @option{-b} or @option{-m}.
1758
1759 @item -j @var{name}
1760 @itemx --section=@var{name}
1761 @cindex section information
1762 Display information only for section @var{name}.
1763
1764 @item -l
1765 @itemx --line-numbers
1766 @cindex source filenames for object files
1767 Label the display (using debugging information) with the filename and
1768 source line numbers corresponding to the object code or relocs shown.
1769 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1770
1771 @item -m @var{machine}
1772 @itemx --architecture=@var{machine}
1773 @cindex architecture
1774 @cindex disassembly architecture
1775 Specify the architecture to use when disassembling object files. This
1776 can be useful when disassembling object files which do not describe
1777 architecture information, such as S-records. You can list the available
1778 architectures with the @option{-i} option.
1779
1780 @item -M @var{options}
1781 @itemx --disassembler-options=@var{options}
1782 Pass target specific information to the disassembler. Only supported on
1783 some targets. If it is necessary to specify more than one
1784 disassembler option then multiple @option{-M} options can be used or
1785 can be placed together into a comma separated list.
1786
1787 If the target is an ARM architecture then this switch can be used to
1788 select which register name set is used during disassembler. Specifying
1789 @option{-M reg-names-std} (the default) will select the register names as
1790 used in ARM's instruction set documentation, but with register 13 called
1791 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1792 @option{-M reg-names-apcs} will select the name set used by the ARM
1793 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1794 just use @samp{r} followed by the register number.
1795
1796 There are also two variants on the APCS register naming scheme enabled
1797 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1798 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1799 with the normal register names or the special register names).
1800
1801 This option can also be used for ARM architectures to force the
1802 disassembler to interpret all instructions as Thumb instructions by
1803 using the switch @option{--disassembler-options=force-thumb}. This can be
1804 useful when attempting to disassemble thumb code produced by other
1805 compilers.
1806
1807 For the x86, some of the options duplicate functions of the @option{-m}
1808 switch, but allow finer grained control. Multiple selections from the
1809 following may be specified as a comma separated string.
1810 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1811 the given architecture. @option{intel} and @option{att} select between
1812 intel syntax mode and AT&T syntax mode. @option{addr64}, @option{addr32},
1813 @option{addr16}, @option{data32} and @option{data16} specify the default
1814 address size and operand size. These four options will be overridden if
1815 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1816 option string. Lastly, @option{suffix}, when in AT&T mode,
1817 instructs the disassembler to print a mnemonic suffix even when the
1818 suffix could be inferred by the operands.
1819
1820 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1821 disassembly of BookE instructions. @option{32} and @option{64} select
1822 PowerPC and PowerPC64 disassembly, respectively. @option{e300}
1823 selects disassembly for the e300 family. @option{440} selects
1824 disassembly for the PowerPC 440. @option{ppcps} selects disassembly
1825 for the paired single instructions of the PPC750CL.
1826
1827 For MIPS, this option controls the printing of instruction mnemonic
1828 names and register names in disassembled instructions. Multiple
1829 selections from the following may be specified as a comma separated
1830 string, and invalid options are ignored:
1831
1832 @table @code
1833 @item no-aliases
1834 Print the 'raw' instruction mnemonic instead of some pseudo
1835 instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
1836 'sll' instead of 'nop', etc.
1837
1838 @item gpr-names=@var{ABI}
1839 Print GPR (general-purpose register) names as appropriate
1840 for the specified ABI. By default, GPR names are selected according to
1841 the ABI of the binary being disassembled.
1842
1843 @item fpr-names=@var{ABI}
1844 Print FPR (floating-point register) names as
1845 appropriate for the specified ABI. By default, FPR numbers are printed
1846 rather than names.
1847
1848 @item cp0-names=@var{ARCH}
1849 Print CP0 (system control coprocessor; coprocessor 0) register names
1850 as appropriate for the CPU or architecture specified by
1851 @var{ARCH}. By default, CP0 register names are selected according to
1852 the architecture and CPU of the binary being disassembled.
1853
1854 @item hwr-names=@var{ARCH}
1855 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1856 as appropriate for the CPU or architecture specified by
1857 @var{ARCH}. By default, HWR names are selected according to
1858 the architecture and CPU of the binary being disassembled.
1859
1860 @item reg-names=@var{ABI}
1861 Print GPR and FPR names as appropriate for the selected ABI.
1862
1863 @item reg-names=@var{ARCH}
1864 Print CPU-specific register names (CP0 register and HWR names)
1865 as appropriate for the selected CPU or architecture.
1866 @end table
1867
1868 For any of the options listed above, @var{ABI} or
1869 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1870 rather than names, for the selected types of registers.
1871 You can list the available values of @var{ABI} and @var{ARCH} using
1872 the @option{--help} option.
1873
1874 For VAX, you can specify function entry addresses with @option{-M
1875 entry:0xf00ba}. You can use this multiple times to properly
1876 disassemble VAX binary files that don't contain symbol tables (like
1877 ROM dumps). In these cases, the function entry mask would otherwise
1878 be decoded as VAX instructions, which would probably lead the rest
1879 of the function being wrongly disassembled.
1880
1881 @item -p
1882 @itemx --private-headers
1883 Print information that is specific to the object file format. The exact
1884 information printed depends upon the object file format. For some
1885 object file formats, no additional information is printed.
1886
1887 @item -r
1888 @itemx --reloc
1889 @cindex relocation entries, in object file
1890 Print the relocation entries of the file. If used with @option{-d} or
1891 @option{-D}, the relocations are printed interspersed with the
1892 disassembly.
1893
1894 @item -R
1895 @itemx --dynamic-reloc
1896 @cindex dynamic relocation entries, in object file
1897 Print the dynamic relocation entries of the file. This is only
1898 meaningful for dynamic objects, such as certain types of shared
1899 libraries.
1900
1901 @item -s
1902 @itemx --full-contents
1903 @cindex sections, full contents
1904 @cindex object file sections
1905 Display the full contents of any sections requested. By default all
1906 non-empty sections are displayed.
1907
1908 @item -S
1909 @itemx --source
1910 @cindex source disassembly
1911 @cindex disassembly, with source
1912 Display source code intermixed with disassembly, if possible. Implies
1913 @option{-d}.
1914
1915 @item --show-raw-insn
1916 When disassembling instructions, print the instruction in hex as well as
1917 in symbolic form. This is the default except when
1918 @option{--prefix-addresses} is used.
1919
1920 @item --no-show-raw-insn
1921 When disassembling instructions, do not print the instruction bytes.
1922 This is the default when @option{--prefix-addresses} is used.
1923
1924 @item -W
1925 @itemx --dwarf
1926 @cindex DWARF
1927 @cindex debug symbols
1928 Displays the contents of the DWARF debug sections in the file, if any
1929 are present.
1930
1931 @item -G
1932 @itemx --stabs
1933 @cindex stab
1934 @cindex .stab
1935 @cindex debug symbols
1936 @cindex ELF object file format
1937 Display the full contents of any sections requested. Display the
1938 contents of the .stab and .stab.index and .stab.excl sections from an
1939 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1940 @code{.stab} debugging symbol-table entries are carried in an ELF
1941 section. In most other file formats, debugging symbol-table entries are
1942 interleaved with linkage symbols, and are visible in the @option{--syms}
1943 output.
1944 @ifclear man
1945 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1946 Overview,stabs.info, The ``stabs'' debug format}.
1947 @end ifclear
1948
1949 @item --start-address=@var{address}
1950 @cindex start-address
1951 Start displaying data at the specified address. This affects the output
1952 of the @option{-d}, @option{-r} and @option{-s} options.
1953
1954 @item --stop-address=@var{address}
1955 @cindex stop-address
1956 Stop displaying data at the specified address. This affects the output
1957 of the @option{-d}, @option{-r} and @option{-s} options.
1958
1959 @item -t
1960 @itemx --syms
1961 @cindex symbol table entries, printing
1962 Print the symbol table entries of the file.
1963 This is similar to the information provided by the @samp{nm} program.
1964
1965 @item -T
1966 @itemx --dynamic-syms
1967 @cindex dynamic symbol table entries, printing
1968 Print the dynamic symbol table entries of the file. This is only
1969 meaningful for dynamic objects, such as certain types of shared
1970 libraries. This is similar to the information provided by the @samp{nm}
1971 program when given the @option{-D} (@option{--dynamic}) option.
1972
1973 @item --special-syms
1974 When displaying symbols include those which the target considers to be
1975 special in some way and which would not normally be of interest to the
1976 user.
1977
1978 @item -V
1979 @itemx --version
1980 Print the version number of @command{objdump} and exit.
1981
1982 @item -x
1983 @itemx --all-headers
1984 @cindex all header information, object file
1985 @cindex header information, all
1986 Display all available header information, including the symbol table and
1987 relocation entries. Using @option{-x} is equivalent to specifying all of
1988 @option{-a -f -h -p -r -t}.
1989
1990 @item -w
1991 @itemx --wide
1992 @cindex wide output, printing
1993 Format some lines for output devices that have more than 80 columns.
1994 Also do not truncate symbol names when they are displayed.
1995
1996 @item -z
1997 @itemx --disassemble-zeroes
1998 Normally the disassembly output will skip blocks of zeroes. This
1999 option directs the disassembler to disassemble those blocks, just like
2000 any other data.
2001 @end table
2002
2003 @c man end
2004
2005 @ignore
2006 @c man begin SEEALSO objdump
2007 nm(1), readelf(1), and the Info entries for @file{binutils}.
2008 @c man end
2009 @end ignore
2010
2011 @node ranlib
2012 @chapter ranlib
2013
2014 @kindex ranlib
2015 @cindex archive contents
2016 @cindex symbol index
2017
2018 @c man title ranlib generate index to archive.
2019
2020 @smallexample
2021 @c man begin SYNOPSIS ranlib
2022 ranlib [@option{-vV}] @var{archive}
2023 @c man end
2024 @end smallexample
2025
2026 @c man begin DESCRIPTION ranlib
2027
2028 @command{ranlib} generates an index to the contents of an archive and
2029 stores it in the archive. The index lists each symbol defined by a
2030 member of an archive that is a relocatable object file.
2031
2032 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2033
2034 An archive with such an index speeds up linking to the library and
2035 allows routines in the library to call each other without regard to
2036 their placement in the archive.
2037
2038 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2039 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
2040 @xref{ar}.
2041
2042 @c man end
2043
2044 @c man begin OPTIONS ranlib
2045
2046 @table @env
2047 @item -v
2048 @itemx -V
2049 @itemx --version
2050 Show the version number of @command{ranlib}.
2051 @end table
2052
2053 @c man end
2054
2055 @ignore
2056 @c man begin SEEALSO ranlib
2057 ar(1), nm(1), and the Info entries for @file{binutils}.
2058 @c man end
2059 @end ignore
2060
2061 @node size
2062 @chapter size
2063
2064 @kindex size
2065 @cindex section sizes
2066
2067 @c man title size list section sizes and total size.
2068
2069 @smallexample
2070 @c man begin SYNOPSIS size
2071 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2072 [@option{--help}]
2073 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2074 [@option{--common}]
2075 [@option{-t}|@option{--totals}]
2076 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2077 [@var{objfile}@dots{}]
2078 @c man end
2079 @end smallexample
2080
2081 @c man begin DESCRIPTION size
2082
2083 The @sc{gnu} @command{size} utility lists the section sizes---and the total
2084 size---for each of the object or archive files @var{objfile} in its
2085 argument list. By default, one line of output is generated for each
2086 object file or each module in an archive.
2087
2088 @var{objfile}@dots{} are the object files to be examined.
2089 If none are specified, the file @code{a.out} will be used.
2090
2091 @c man end
2092
2093 @c man begin OPTIONS size
2094
2095 The command line options have the following meanings:
2096
2097 @table @env
2098 @item -A
2099 @itemx -B
2100 @itemx --format=@var{compatibility}
2101 @cindex @command{size} display format
2102 Using one of these options, you can choose whether the output from @sc{gnu}
2103 @command{size} resembles output from System V @command{size} (using @option{-A},
2104 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2105 @option{--format=berkeley}). The default is the one-line format similar to
2106 Berkeley's.
2107 @c Bonus for doc-source readers: you can also say --format=strange (or
2108 @c anything else that starts with 's') for sysv, and --format=boring (or
2109 @c anything else that starts with 'b') for Berkeley.
2110
2111 Here is an example of the Berkeley (default) format of output from
2112 @command{size}:
2113 @smallexample
2114 $ size --format=Berkeley ranlib size
2115 text data bss dec hex filename
2116 294880 81920 11592 388392 5ed28 ranlib
2117 294880 81920 11888 388688 5ee50 size
2118 @end smallexample
2119
2120 @noindent
2121 This is the same data, but displayed closer to System V conventions:
2122
2123 @smallexample
2124 $ size --format=SysV ranlib size
2125 ranlib :
2126 section size addr
2127 .text 294880 8192
2128 .data 81920 303104
2129 .bss 11592 385024
2130 Total 388392
2131
2132
2133 size :
2134 section size addr
2135 .text 294880 8192
2136 .data 81920 303104
2137 .bss 11888 385024
2138 Total 388688
2139 @end smallexample
2140
2141 @item --help
2142 Show a summary of acceptable arguments and options.
2143
2144 @item -d
2145 @itemx -o
2146 @itemx -x
2147 @itemx --radix=@var{number}
2148 @cindex @command{size} number format
2149 @cindex radix for section sizes
2150 Using one of these options, you can control whether the size of each
2151 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2152 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2153 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
2154 values (8, 10, 16) are supported. The total size is always given in two
2155 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2156 octal and hexadecimal if you're using @option{-o}.
2157
2158 @item --common
2159 Print total size of common symbols in each file. When using Berkeley
2160 format these are included in the bss size.
2161
2162 @item -t
2163 @itemx --totals
2164 Show totals of all objects listed (Berkeley format listing mode only).
2165
2166 @item --target=@var{bfdname}
2167 @cindex object code format
2168 Specify that the object-code format for @var{objfile} is
2169 @var{bfdname}. This option may not be necessary; @command{size} can
2170 automatically recognize many formats.
2171 @xref{Target Selection}, for more information.
2172
2173 @item -V
2174 @itemx --version
2175 Display the version number of @command{size}.
2176 @end table
2177
2178 @c man end
2179
2180 @ignore
2181 @c man begin SEEALSO size
2182 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2183 @c man end
2184 @end ignore
2185
2186 @node strings
2187 @chapter strings
2188 @kindex strings
2189 @cindex listings strings
2190 @cindex printing strings
2191 @cindex strings, printing
2192
2193 @c man title strings print the strings of printable characters in files.
2194
2195 @smallexample
2196 @c man begin SYNOPSIS strings
2197 strings [@option{-afov}] [@option{-}@var{min-len}]
2198 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2199 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2200 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2201 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2202 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2203 [@option{--help}] [@option{--version}] @var{file}@dots{}
2204 @c man end
2205 @end smallexample
2206
2207 @c man begin DESCRIPTION strings
2208
2209 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2210 character sequences that are at least 4 characters long (or the number
2211 given with the options below) and are followed by an unprintable
2212 character. By default, it only prints the strings from the initialized
2213 and loaded sections of object files; for other types of files, it prints
2214 the strings from the whole file.
2215
2216 @command{strings} is mainly useful for determining the contents of non-text
2217 files.
2218
2219 @c man end
2220
2221 @c man begin OPTIONS strings
2222
2223 @table @env
2224 @item -a
2225 @itemx --all
2226 @itemx -
2227 Do not scan only the initialized and loaded sections of object files;
2228 scan the whole files.
2229
2230 @item -f
2231 @itemx --print-file-name
2232 Print the name of the file before each string.
2233
2234 @item --help
2235 Print a summary of the program usage on the standard output and exit.
2236
2237 @item -@var{min-len}
2238 @itemx -n @var{min-len}
2239 @itemx --bytes=@var{min-len}
2240 Print sequences of characters that are at least @var{min-len} characters
2241 long, instead of the default 4.
2242
2243 @item -o
2244 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2245 act like @samp{-t d} instead. Since we can not be compatible with both
2246 ways, we simply chose one.
2247
2248 @item -t @var{radix}
2249 @itemx --radix=@var{radix}
2250 Print the offset within the file before each string. The single
2251 character argument specifies the radix of the offset---@samp{o} for
2252 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2253
2254 @item -e @var{encoding}
2255 @itemx --encoding=@var{encoding}
2256 Select the character encoding of the strings that are to be found.
2257 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2258 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2259 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2260 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2261 littleendian. Useful for finding wide character strings.
2262
2263 @item -T @var{bfdname}
2264 @itemx --target=@var{bfdname}
2265 @cindex object code format
2266 Specify an object code format other than your system's default format.
2267 @xref{Target Selection}, for more information.
2268
2269 @item -v
2270 @itemx --version
2271 Print the program version number on the standard output and exit.
2272 @end table
2273
2274 @c man end
2275
2276 @ignore
2277 @c man begin SEEALSO strings
2278 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2279 and the Info entries for @file{binutils}.
2280 @c man end
2281 @end ignore
2282
2283 @node strip
2284 @chapter strip
2285
2286 @kindex strip
2287 @cindex removing symbols
2288 @cindex discarding symbols
2289 @cindex symbols, discarding
2290
2291 @c man title strip Discard symbols from object files.
2292
2293 @smallexample
2294 @c man begin SYNOPSIS strip
2295 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2296 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2297 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2298 [@option{-s}|@option{--strip-all}]
2299 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2300 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2301 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2302 [@option{-w}|@option{--wildcard}]
2303 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2304 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2305 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2306 [@option{--keep-file-symbols}]
2307 [@option{--only-keep-debug}]
2308 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2309 [@option{--help}] [@option{--info}]
2310 @var{objfile}@dots{}
2311 @c man end
2312 @end smallexample
2313
2314 @c man begin DESCRIPTION strip
2315
2316 @sc{gnu} @command{strip} discards all symbols from object files
2317 @var{objfile}. The list of object files may include archives.
2318 At least one object file must be given.
2319
2320 @command{strip} modifies the files named in its argument,
2321 rather than writing modified copies under different names.
2322
2323 @c man end
2324
2325 @c man begin OPTIONS strip
2326
2327 @table @env
2328 @item -F @var{bfdname}
2329 @itemx --target=@var{bfdname}
2330 Treat the original @var{objfile} as a file with the object
2331 code format @var{bfdname}, and rewrite it in the same format.
2332 @xref{Target Selection}, for more information.
2333
2334 @item --help
2335 Show a summary of the options to @command{strip} and exit.
2336
2337 @item --info
2338 Display a list showing all architectures and object formats available.
2339
2340 @item -I @var{bfdname}
2341 @itemx --input-target=@var{bfdname}
2342 Treat the original @var{objfile} as a file with the object
2343 code format @var{bfdname}.
2344 @xref{Target Selection}, for more information.
2345
2346 @item -O @var{bfdname}
2347 @itemx --output-target=@var{bfdname}
2348 Replace @var{objfile} with a file in the output format @var{bfdname}.
2349 @xref{Target Selection}, for more information.
2350
2351 @item -R @var{sectionname}
2352 @itemx --remove-section=@var{sectionname}
2353 Remove any section named @var{sectionname} from the output file. This
2354 option may be given more than once. Note that using this option
2355 inappropriately may make the output file unusable.
2356
2357 @item -s
2358 @itemx --strip-all
2359 Remove all symbols.
2360
2361 @item -g
2362 @itemx -S
2363 @itemx -d
2364 @itemx --strip-debug
2365 Remove debugging symbols only.
2366
2367 @item --strip-unneeded
2368 Remove all symbols that are not needed for relocation processing.
2369
2370 @item -K @var{symbolname}
2371 @itemx --keep-symbol=@var{symbolname}
2372 When stripping symbols, keep symbol @var{symbolname} even if it would
2373 normally be stripped. This option may be given more than once.
2374
2375 @item -N @var{symbolname}
2376 @itemx --strip-symbol=@var{symbolname}
2377 Remove symbol @var{symbolname} from the source file. This option may be
2378 given more than once, and may be combined with strip options other than
2379 @option{-K}.
2380
2381 @item -o @var{file}
2382 Put the stripped output in @var{file}, rather than replacing the
2383 existing file. When this argument is used, only one @var{objfile}
2384 argument may be specified.
2385
2386 @item -p
2387 @itemx --preserve-dates
2388 Preserve the access and modification dates of the file.
2389
2390 @item -w
2391 @itemx --wildcard
2392 Permit regular expressions in @var{symbolname}s used in other command
2393 line options. The question mark (?), asterisk (*), backslash (\) and
2394 square brackets ([]) operators can be used anywhere in the symbol
2395 name. If the first character of the symbol name is the exclamation
2396 point (!) then the sense of the switch is reversed for that symbol.
2397 For example:
2398
2399 @smallexample
2400 -w -K !foo -K fo*
2401 @end smallexample
2402
2403 would cause strip to only keep symbols that start with the letters
2404 ``fo'', but to discard the symbol ``foo''.
2405
2406 @item -x
2407 @itemx --discard-all
2408 Remove non-global symbols.
2409
2410 @item -X
2411 @itemx --discard-locals
2412 Remove compiler-generated local symbols.
2413 (These usually start with @samp{L} or @samp{.}.)
2414
2415 @item --keep-file-symbols
2416 When stripping a file, perhaps with @option{--strip-debug} or
2417 @option{--strip-unneeded}, retain any symbols specifying source file names,
2418 which would otherwise get stripped.
2419
2420 @item --only-keep-debug
2421 Strip a file, removing contents of any sections that would not be
2422 stripped by @option{--strip-debug} and leaving the debugging sections
2423 intact. In ELF files, this preserves all note sections in the output.
2424
2425 The intention is that this option will be used in conjunction with
2426 @option{--add-gnu-debuglink} to create a two part executable. One a
2427 stripped binary which will occupy less space in RAM and in a
2428 distribution and the second a debugging information file which is only
2429 needed if debugging abilities are required. The suggested procedure
2430 to create these files is as follows:
2431
2432 @enumerate
2433 @item Link the executable as normal. Assuming that is is called
2434 @code{foo} then...
2435 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2436 create a file containing the debugging info.
2437 @item Run @code{objcopy --strip-debug foo} to create a
2438 stripped executable.
2439 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2440 to add a link to the debugging info into the stripped executable.
2441 @end enumerate
2442
2443 Note - the choice of @code{.dbg} as an extension for the debug info
2444 file is arbitrary. Also the @code{--only-keep-debug} step is
2445 optional. You could instead do this:
2446
2447 @enumerate
2448 @item Link the executable as normal.
2449 @item Copy @code{foo} to @code{foo.full}
2450 @item Run @code{strip --strip-debug foo}
2451 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2452 @end enumerate
2453
2454 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2455 full executable. It does not have to be a file created by the
2456 @option{--only-keep-debug} switch.
2457
2458 Note - this switch is only intended for use on fully linked files. It
2459 does not make sense to use it on object files where the debugging
2460 information may be incomplete. Besides the gnu_debuglink feature
2461 currently only supports the presence of one filename containing
2462 debugging information, not multiple filenames on a one-per-object-file
2463 basis.
2464
2465 @item -V
2466 @itemx --version
2467 Show the version number for @command{strip}.
2468
2469 @item -v
2470 @itemx --verbose
2471 Verbose output: list all object files modified. In the case of
2472 archives, @samp{strip -v} lists all members of the archive.
2473 @end table
2474
2475 @c man end
2476
2477 @ignore
2478 @c man begin SEEALSO strip
2479 the Info entries for @file{binutils}.
2480 @c man end
2481 @end ignore
2482
2483 @node c++filt, addr2line, strip, Top
2484 @chapter c++filt
2485
2486 @kindex c++filt
2487 @cindex demangling C++ symbols
2488
2489 @c man title cxxfilt Demangle C++ and Java symbols.
2490
2491 @smallexample
2492 @c man begin SYNOPSIS cxxfilt
2493 c++filt [@option{-_}|@option{--strip-underscores}]
2494 [@option{-n}|@option{--no-strip-underscores}]
2495 [@option{-p}|@option{--no-params}]
2496 [@option{-t}|@option{--types}]
2497 [@option{-i}|@option{--no-verbose}]
2498 [@option{-s} @var{format}|@option{--format=}@var{format}]
2499 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2500 @c man end
2501 @end smallexample
2502
2503 @c man begin DESCRIPTION cxxfilt
2504
2505 @kindex cxxfilt
2506 The C++ and Java languages provide function overloading, which means
2507 that you can write many functions with the same name, providing that
2508 each function takes parameters of different types. In order to be
2509 able to distinguish these similarly named functions C++ and Java
2510 encode them into a low-level assembler name which uniquely identifies
2511 each different version. This process is known as @dfn{mangling}. The
2512 @command{c++filt}
2513 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2514 MS-DOS this program is named @command{CXXFILT}.}
2515 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2516 names into user-level names so that they can be read.
2517
2518 Every alphanumeric word (consisting of letters, digits, underscores,
2519 dollars, or periods) seen in the input is a potential mangled name.
2520 If the name decodes into a C++ name, the C++ name replaces the
2521 low-level name in the output, otherwise the original word is output.
2522 In this way you can pass an entire assembler source file, containing
2523 mangled names, through @command{c++filt} and see the same source file
2524 containing demangled names.
2525
2526 You can also use @command{c++filt} to decipher individual symbols by
2527 passing them on the command line:
2528
2529 @example
2530 c++filt @var{symbol}
2531 @end example
2532
2533 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2534 names from the standard input instead. All the results are printed on
2535 the standard output. The difference between reading names from the
2536 command line versus reading names from the standard input is that
2537 command line arguments are expected to be just mangled names and no
2538 checking is performed to separate them from surrounding text. Thus
2539 for example:
2540
2541 @smallexample
2542 c++filt -n _Z1fv
2543 @end smallexample
2544
2545 will work and demangle the name to ``f()'' whereas:
2546
2547 @smallexample
2548 c++filt -n _Z1fv,
2549 @end smallexample
2550
2551 will not work. (Note the extra comma at the end of the mangled
2552 name which makes it invalid). This command however will work:
2553
2554 @smallexample
2555 echo _Z1fv, | c++filt -n
2556 @end smallexample
2557
2558 and will display ``f(),'' ie the demangled name followed by a
2559 trailing comma. This behaviour is because when the names are read
2560 from the standard input it is expected that they might be part of an
2561 assembler source file where there might be extra, extraneous
2562 characters trailing after a mangled name. eg:
2563
2564 @smallexample
2565 .type _Z1fv, @@function
2566 @end smallexample
2567
2568 @c man end
2569
2570 @c man begin OPTIONS cxxfilt
2571
2572 @table @env
2573 @item -_
2574 @itemx --strip-underscores
2575 On some systems, both the C and C++ compilers put an underscore in front
2576 of every name. For example, the C name @code{foo} gets the low-level
2577 name @code{_foo}. This option removes the initial underscore. Whether
2578 @command{c++filt} removes the underscore by default is target dependent.
2579
2580 @item -j
2581 @itemx --java
2582 Prints demangled names using Java syntax. The default is to use C++
2583 syntax.
2584
2585 @item -n
2586 @itemx --no-strip-underscores
2587 Do not remove the initial underscore.
2588
2589 @item -p
2590 @itemx --no-params
2591 When demangling the name of a function, do not display the types of
2592 the function's parameters.
2593
2594 @item -t
2595 @itemx --types
2596 Attempt to demangle types as well as function names. This is disabled
2597 by default since mangled types are normally only used internally in
2598 the compiler, and they can be confused with non-mangled names. eg
2599 a function called ``a'' treated as a mangled type name would be
2600 demangled to ``signed char''.
2601
2602 @item -i
2603 @itemx --no-verbose
2604 Do not include implementation details (if any) in the demangled
2605 output.
2606
2607 @item -s @var{format}
2608 @itemx --format=@var{format}
2609 @command{c++filt} can decode various methods of mangling, used by
2610 different compilers. The argument to this option selects which
2611 method it uses:
2612
2613 @table @code
2614 @item auto
2615 Automatic selection based on executable (the default method)
2616 @item gnu
2617 the one used by the @sc{gnu} C++ compiler (g++)
2618 @item lucid
2619 the one used by the Lucid compiler (lcc)
2620 @item arm
2621 the one specified by the C++ Annotated Reference Manual
2622 @item hp
2623 the one used by the HP compiler (aCC)
2624 @item edg
2625 the one used by the EDG compiler
2626 @item gnu-v3
2627 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2628 @item java
2629 the one used by the @sc{gnu} Java compiler (gcj)
2630 @item gnat
2631 the one used by the @sc{gnu} Ada compiler (GNAT).
2632 @end table
2633
2634 @item --help
2635 Print a summary of the options to @command{c++filt} and exit.
2636
2637 @item --version
2638 Print the version number of @command{c++filt} and exit.
2639 @end table
2640
2641 @c man end
2642
2643 @ignore
2644 @c man begin SEEALSO cxxfilt
2645 the Info entries for @file{binutils}.
2646 @c man end
2647 @end ignore
2648
2649 @quotation
2650 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2651 user interface are subject to change in future releases. In particular,
2652 a command-line option may be required in the future to decode a name
2653 passed as an argument on the command line; in other words,
2654
2655 @example
2656 c++filt @var{symbol}
2657 @end example
2658
2659 @noindent
2660 may in a future release become
2661
2662 @example
2663 c++filt @var{option} @var{symbol}
2664 @end example
2665 @end quotation
2666
2667 @node addr2line
2668 @chapter addr2line
2669
2670 @kindex addr2line
2671 @cindex address to file name and line number
2672
2673 @c man title addr2line convert addresses into file names and line numbers.
2674
2675 @smallexample
2676 @c man begin SYNOPSIS addr2line
2677 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2678 [@option{-C}|@option{--demangle}[=@var{style}]]
2679 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2680 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2681 [@option{-i}|@option{--inlines}]
2682 [@option{-j}|@option{--section=}@var{name}]
2683 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2684 [addr addr @dots{}]
2685 @c man end
2686 @end smallexample
2687
2688 @c man begin DESCRIPTION addr2line
2689
2690 @command{addr2line} translates addresses into file names and line numbers.
2691 Given an address in an executable or an offset in a section of a relocatable
2692 object, it uses the debugging information to figure out which file name and
2693 line number are associated with it.
2694
2695 The executable or relocatable object to use is specified with the @option{-e}
2696 option. The default is the file @file{a.out}. The section in the relocatable
2697 object to use is specified with the @option{-j} option.
2698
2699 @command{addr2line} has two modes of operation.
2700
2701 In the first, hexadecimal addresses are specified on the command line,
2702 and @command{addr2line} displays the file name and line number for each
2703 address.
2704
2705 In the second, @command{addr2line} reads hexadecimal addresses from
2706 standard input, and prints the file name and line number for each
2707 address on standard output. In this mode, @command{addr2line} may be used
2708 in a pipe to convert dynamically chosen addresses.
2709
2710 The format of the output is @samp{FILENAME:LINENO}. The file name and
2711 line number for each address is printed on a separate line. If the
2712 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2713 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2714 containing the address.
2715
2716 If the file name or function name can not be determined,
2717 @command{addr2line} will print two question marks in their place. If the
2718 line number can not be determined, @command{addr2line} will print 0.
2719
2720 @c man end
2721
2722 @c man begin OPTIONS addr2line
2723
2724 The long and short forms of options, shown here as alternatives, are
2725 equivalent.
2726
2727 @table @env
2728 @item -b @var{bfdname}
2729 @itemx --target=@var{bfdname}
2730 @cindex object code format
2731 Specify that the object-code format for the object files is
2732 @var{bfdname}.
2733
2734 @item -C
2735 @itemx --demangle[=@var{style}]
2736 @cindex demangling in objdump
2737 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2738 Besides removing any initial underscore prepended by the system, this
2739 makes C++ function names readable. Different compilers have different
2740 mangling styles. The optional demangling style argument can be used to
2741 choose an appropriate demangling style for your compiler. @xref{c++filt},
2742 for more information on demangling.
2743
2744 @item -e @var{filename}
2745 @itemx --exe=@var{filename}
2746 Specify the name of the executable for which addresses should be
2747 translated. The default file is @file{a.out}.
2748
2749 @item -f
2750 @itemx --functions
2751 Display function names as well as file and line number information.
2752
2753 @item -s
2754 @itemx --basenames
2755 Display only the base of each file name.
2756
2757 @item -i
2758 @itemx --inlines
2759 If the address belongs to a function that was inlined, the source
2760 information for all enclosing scopes back to the first non-inlined
2761 function will also be printed. For example, if @code{main} inlines
2762 @code{callee1} which inlines @code{callee2}, and address is from
2763 @code{callee2}, the source information for @code{callee1} and @code{main}
2764 will also be printed.
2765
2766 @item -j
2767 @itemx --section
2768 Read offsets relative to the specified section instead of absolute addresses.
2769 @end table
2770
2771 @c man end
2772
2773 @ignore
2774 @c man begin SEEALSO addr2line
2775 Info entries for @file{binutils}.
2776 @c man end
2777 @end ignore
2778
2779 @node nlmconv
2780 @chapter nlmconv
2781
2782 @command{nlmconv} converts a relocatable object file into a NetWare
2783 Loadable Module.
2784
2785 @ignore
2786 @command{nlmconv} currently works with @samp{i386} object
2787 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2788 object files in @sc{elf}, or @code{a.out} format@footnote{
2789 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2790 format in the Binary File Descriptor library. It has only been tested
2791 with the above formats.}.
2792 @end ignore
2793
2794 @quotation
2795 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2796 utilities, since it is only useful for NLM targets.
2797 @end quotation
2798
2799 @c man title nlmconv converts object code into an NLM.
2800
2801 @smallexample
2802 @c man begin SYNOPSIS nlmconv
2803 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2804 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2805 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2806 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2807 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2808 @var{infile} @var{outfile}
2809 @c man end
2810 @end smallexample
2811
2812 @c man begin DESCRIPTION nlmconv
2813
2814 @command{nlmconv} converts the relocatable @samp{i386} object file
2815 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2816 reading @var{headerfile} for NLM header information. For instructions
2817 on writing the NLM command file language used in header files, see the
2818 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2819 Development and Tools Overview}, which is part of the NLM Software
2820 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2821 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2822 @var{infile};
2823 @ifclear man
2824 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2825 @end ifclear
2826
2827 @command{nlmconv} can perform a link step. In other words, you can list
2828 more than one object file for input if you list them in the definitions
2829 file (rather than simply specifying one input file on the command line).
2830 In this case, @command{nlmconv} calls the linker for you.
2831
2832 @c man end
2833
2834 @c man begin OPTIONS nlmconv
2835
2836 @table @env
2837 @item -I @var{bfdname}
2838 @itemx --input-target=@var{bfdname}
2839 Object format of the input file. @command{nlmconv} can usually determine
2840 the format of a given file (so no default is necessary).
2841 @xref{Target Selection}, for more information.
2842
2843 @item -O @var{bfdname}
2844 @itemx --output-target=@var{bfdname}
2845 Object format of the output file. @command{nlmconv} infers the output
2846 format based on the input format, e.g. for a @samp{i386} input file the
2847 output format is @samp{nlm32-i386}.
2848 @xref{Target Selection}, for more information.
2849
2850 @item -T @var{headerfile}
2851 @itemx --header-file=@var{headerfile}
2852 Reads @var{headerfile} for NLM header information. For instructions on
2853 writing the NLM command file language used in header files, see@ see the
2854 @samp{linkers} section, of the @cite{NLM Development and Tools
2855 Overview}, which is part of the NLM Software Developer's Kit, available
2856 from Novell, Inc.
2857
2858 @item -d
2859 @itemx --debug
2860 Displays (on standard error) the linker command line used by @command{nlmconv}.
2861
2862 @item -l @var{linker}
2863 @itemx --linker=@var{linker}
2864 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2865 relative pathname.
2866
2867 @item -h
2868 @itemx --help
2869 Prints a usage summary.
2870
2871 @item -V
2872 @itemx --version
2873 Prints the version number for @command{nlmconv}.
2874 @end table
2875
2876 @c man end
2877
2878 @ignore
2879 @c man begin SEEALSO nlmconv
2880 the Info entries for @file{binutils}.
2881 @c man end
2882 @end ignore
2883
2884 @node windmc
2885 @chapter windmc
2886
2887 @command{windmc} may be used to generator Windows message resources.
2888
2889 @quotation
2890 @emph{Warning:} @command{windmc} is not always built as part of the binary
2891 utilities, since it is only useful for Windows targets.
2892 @end quotation
2893
2894 @c man title windmc generates Windows message resources.
2895
2896 @smallexample
2897 @c man begin SYNOPSIS windres
2898 windmc [options] input-file
2899 @c man end
2900 @end smallexample
2901
2902 @c man begin DESCRIPTION windmc
2903
2904 @command{windmc} reads message definitions from an input file (.mc) and
2905 translate them into a set of output files. The output files may be of
2906 four kinds:
2907
2908 @table @code
2909 @item h
2910 A C header file containing the message definitions.
2911
2912 @item rc
2913 A resource file compilable by the @command{windres} tool.
2914
2915 @item bin
2916 One or more binary files containing the resource data for a specific
2917 message language.
2918
2919 @item dbg
2920 A C include file that maps message id's to their symbolic name.
2921 @end table
2922
2923 The exact description of these different formats is available in
2924 documentation from Microsoft.
2925
2926 When @command{windmc} converts from the @code{mc} format to the @code{bin}
2927 format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
2928 Windows Message Compiler.
2929
2930 @c man end
2931
2932 @c man begin OPTIONS windmc
2933
2934 @table @env
2935 @item -a
2936 @itemx --ascii_in
2937 Specifies that the input file specified is ANSI. This is the default
2938 behaviour.
2939
2940 @item -A
2941 @itemx --ascii_out
2942 Specifies that messages in the output @code{bin} files should be in ANSI
2943 format.
2944
2945 @item -b
2946 @itemx --binprefix
2947 Specifies that @code{bin} filenames should have to be prefixed by the
2948 basename of the source file.
2949
2950 @item -c
2951 @itemx --customflag
2952 Sets the customer bit in all message id's.
2953
2954 @item -C @var{codepage}
2955 @itemx --codepage_in @var{codepage}
2956 Sets the default codepage to be used to convert input file to UTF16. The
2957 default is ocdepage 1252.
2958
2959 @item -d
2960 @itemx --decimal_values
2961 Outputs the constants in the header file in decimal. Default is using
2962 hexadecimal output.
2963
2964 @item -e @var{ext}
2965 @itemx --extension @var{ext}
2966 The extension for the header file. The default is .h extension.
2967
2968 @item -F @var{target}
2969 @itemx --target @var{target}
2970 Specify the BFD format to use for a bin file as output. This
2971 is a BFD target name; you can use the @option{--help} option to see a list
2972 of supported targets. Normally @command{windmc} will use the default
2973 format, which is the first one listed by the @option{--help} option.
2974 @ifclear man
2975 @ref{Target Selection}.
2976 @end ifclear
2977
2978 @item -h @var{path}
2979 @itemx --headerdir @var{path}
2980 The target directory of the generated header file. The default is the
2981 current directory.
2982
2983 @item -H
2984 @itemx --help
2985 Displays a list of command line options and then exits.
2986
2987 @item -m @var{characters}
2988 @itemx --maxlength @var{characters}
2989 Instructs @command{windmc} to generate a warning if the length
2990 of any message exceeds the number specified.
2991
2992 @item -n
2993 @itemx --nullterminate
2994 Terminate message text in @code{bin} files by zero. By default they are
2995 terminated by CR/LF.
2996
2997 @item -o
2998 @itemx --hresult_use
2999 Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3000 file, using HRESULT definitions. Status codes are used if the flag is not
3001 specified.
3002
3003 @item -O @var{codepage}
3004 @itemx --codepage_out @var{codepage}
3005 Sets the default codepage to be used to output text files. The default
3006 is ocdepage 1252.
3007
3008 @item -r @var{path}
3009 @itemx --rcdir @var{path}
3010 The target directory for the generated @code{rc} script and the generated
3011 @code{bin} files that the resource compiler script includes. The default
3012 is the current directory.
3013
3014 @item -u
3015 @itemx --unicode_in
3016 Specifies that the input file is UTF16.
3017
3018 @item -U
3019 @itemx --unicode_out
3020 Specifies that messages in the output @code{bin} file should be in UTF16
3021 format. This is the default behaviour.
3022
3023 @item -v
3024 @item --verbose
3025 Enable verbose mode.
3026
3027 @item -V
3028 @item --version
3029 Prints the version number for @command{windmc}.
3030
3031 @item -x @var{path}
3032 @itemx --xdgb @var{path}
3033 The path of the @code{dbg} C include file that maps message id's to the
3034 symbolic name. No such file is generated without specifying the switch.
3035 @end table
3036
3037 @c man end
3038
3039 @ignore
3040 @c man begin SEEALSO windmc
3041 the Info entries for @file{binutils}.
3042 @c man end
3043 @end ignore
3044
3045 @node windres
3046 @chapter windres
3047
3048 @command{windres} may be used to manipulate Windows resources.
3049
3050 @quotation
3051 @emph{Warning:} @command{windres} is not always built as part of the binary
3052 utilities, since it is only useful for Windows targets.
3053 @end quotation
3054
3055 @c man title windres manipulate Windows resources.
3056
3057 @smallexample
3058 @c man begin SYNOPSIS windres
3059 windres [options] [input-file] [output-file]
3060 @c man end
3061 @end smallexample
3062
3063 @c man begin DESCRIPTION windres
3064
3065 @command{windres} reads resources from an input file and copies them into
3066 an output file. Either file may be in one of three formats:
3067
3068 @table @code
3069 @item rc
3070 A text format read by the Resource Compiler.
3071
3072 @item res
3073 A binary format generated by the Resource Compiler.
3074
3075 @item coff
3076 A COFF object or executable.
3077 @end table
3078
3079 The exact description of these different formats is available in
3080 documentation from Microsoft.
3081
3082 When @command{windres} converts from the @code{rc} format to the @code{res}
3083 format, it is acting like the Windows Resource Compiler. When
3084 @command{windres} converts from the @code{res} format to the @code{coff}
3085 format, it is acting like the Windows @code{CVTRES} program.
3086
3087 When @command{windres} generates an @code{rc} file, the output is similar
3088 but not identical to the format expected for the input. When an input
3089 @code{rc} file refers to an external filename, an output @code{rc} file
3090 will instead include the file contents.
3091
3092 If the input or output format is not specified, @command{windres} will
3093 guess based on the file name, or, for the input file, the file contents.
3094 A file with an extension of @file{.rc} will be treated as an @code{rc}
3095 file, a file with an extension of @file{.res} will be treated as a
3096 @code{res} file, and a file with an extension of @file{.o} or
3097 @file{.exe} will be treated as a @code{coff} file.
3098
3099 If no output file is specified, @command{windres} will print the resources
3100 in @code{rc} format to standard output.
3101
3102 The normal use is for you to write an @code{rc} file, use @command{windres}
3103 to convert it to a COFF object file, and then link the COFF file into
3104 your application. This will make the resources described in the
3105 @code{rc} file available to Windows.
3106
3107 @c man end
3108
3109 @c man begin OPTIONS windres
3110
3111 @table @env
3112 @item -i @var{filename}
3113 @itemx --input @var{filename}
3114 The name of the input file. If this option is not used, then
3115 @command{windres} will use the first non-option argument as the input file
3116 name. If there are no non-option arguments, then @command{windres} will
3117 read from standard input. @command{windres} can not read a COFF file from
3118 standard input.
3119
3120 @item -o @var{filename}
3121 @itemx --output @var{filename}
3122 The name of the output file. If this option is not used, then
3123 @command{windres} will use the first non-option argument, after any used
3124 for the input file name, as the output file name. If there is no
3125 non-option argument, then @command{windres} will write to standard output.
3126 @command{windres} can not write a COFF file to standard output. Note,
3127 for compatibility with @command{rc} the option @option{-fo} is also
3128 accepted, but its use is not recommended.
3129
3130 @item -J @var{format}
3131 @itemx --input-format @var{format}
3132 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3133 @samp{coff}. If no input format is specified, @command{windres} will
3134 guess, as described above.
3135
3136 @item -O @var{format}
3137 @itemx --output-format @var{format}
3138 The output format to generate. @var{format} may be @samp{res},
3139 @samp{rc}, or @samp{coff}. If no output format is specified,
3140 @command{windres} will guess, as described above.
3141
3142 @item -F @var{target}
3143 @itemx --target @var{target}
3144 Specify the BFD format to use for a COFF file as input or output. This
3145 is a BFD target name; you can use the @option{--help} option to see a list
3146 of supported targets. Normally @command{windres} will use the default
3147 format, which is the first one listed by the @option{--help} option.
3148 @ifclear man
3149 @ref{Target Selection}.
3150 @end ifclear
3151
3152 @item --preprocessor @var{program}
3153 When @command{windres} reads an @code{rc} file, it runs it through the C
3154 preprocessor first. This option may be used to specify the preprocessor
3155 to use, including any leading arguments. The default preprocessor
3156 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3157
3158 @item -I @var{directory}
3159 @itemx --include-dir @var{directory}
3160 Specify an include directory to use when reading an @code{rc} file.
3161 @command{windres} will pass this to the preprocessor as an @option{-I}
3162 option. @command{windres} will also search this directory when looking for
3163 files named in the @code{rc} file. If the argument passed to this command
3164 matches any of the supported @var{formats} (as described in the @option{-J}
3165 option), it will issue a deprecation warning, and behave just like the
3166 @option{-J} option. New programs should not use this behaviour. If a
3167 directory happens to match a @var{format}, simple prefix it with @samp{./}
3168 to disable the backward compatibility.
3169
3170 @item -D @var{target}
3171 @itemx --define @var{sym}[=@var{val}]
3172 Specify a @option{-D} option to pass to the preprocessor when reading an
3173 @code{rc} file.
3174
3175 @item -U @var{target}
3176 @itemx --undefine @var{sym}
3177 Specify a @option{-U} option to pass to the preprocessor when reading an
3178 @code{rc} file.
3179
3180 @item -r
3181 Ignored for compatibility with rc.
3182
3183 @item -v
3184 Enable verbose mode. This tells you what the preprocessor is if you
3185 didn't specify one.
3186
3187 @item -c @var{val}
3188 @item --codepage @var{val}
3189 Specify the default codepage to use when reading an @code{rc} file.
3190 @var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
3191 codepage code. The valid range is from zero up to 0xffff, but the
3192 validity of the codepage is host and configuration dependent.
3193
3194 @item -l @var{val}
3195 @item --language @var{val}
3196 Specify the default language to use when reading an @code{rc} file.
3197 @var{val} should be a hexadecimal language code. The low eight bits are
3198 the language, and the high eight bits are the sublanguage.
3199
3200 @item --use-temp-file
3201 Use a temporary file to instead of using popen to read the output of
3202 the preprocessor. Use this option if the popen implementation is buggy
3203 on the host (eg., certain non-English language versions of Windows 95 and
3204 Windows 98 are known to have buggy popen where the output will instead
3205 go the console).
3206
3207 @item --no-use-temp-file
3208 Use popen, not a temporary file, to read the output of the preprocessor.
3209 This is the default behaviour.
3210
3211 @item -h
3212 @item --help
3213 Prints a usage summary.
3214
3215 @item -V
3216 @item --version
3217 Prints the version number for @command{windres}.
3218
3219 @item --yydebug
3220 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3221 this will turn on parser debugging.
3222 @end table
3223
3224 @c man end
3225
3226 @ignore
3227 @c man begin SEEALSO windres
3228 the Info entries for @file{binutils}.
3229 @c man end
3230 @end ignore
3231
3232 @node dlltool
3233 @chapter dlltool
3234 @cindex DLL
3235 @kindex dlltool
3236
3237 @command{dlltool} is used to create the files needed to create dynamic
3238 link libraries (DLLs) on systems which understand PE format image
3239 files such as Windows. A DLL contains an export table which contains
3240 information that the runtime loader needs to resolve references from a
3241 referencing program.
3242
3243 The export table is generated by this program by reading in a
3244 @file{.def} file or scanning the @file{.a} and @file{.o} files which
3245 will be in the DLL. A @file{.o} file can contain information in
3246 special @samp{.drectve} sections with export information.
3247
3248 @quotation
3249 @emph{Note:} @command{dlltool} is not always built as part of the
3250 binary utilities, since it is only useful for those targets which
3251 support DLLs.
3252 @end quotation
3253
3254 @c man title dlltool Create files needed to build and use DLLs.
3255
3256 @smallexample
3257 @c man begin SYNOPSIS dlltool
3258 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3259 [@option{-b}|@option{--base-file} @var{base-file-name}]
3260 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3261 [@option{-z}|@option{--output-def} @var{def-file-name}]
3262 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3263 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3264 [@option{--exclude-symbols} @var{list}]
3265 [@option{--no-default-excludes}]
3266 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3267 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3268 [@option{-a}|@option{--add-indirect}]
3269 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3270 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3271 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3272 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
3273 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3274 [@option{-v}|@option{--verbose}]
3275 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3276 [object-file @dots{}]
3277 @c man end
3278 @end smallexample
3279
3280 @c man begin DESCRIPTION dlltool
3281
3282 @command{dlltool} reads its inputs, which can come from the @option{-d} and
3283 @option{-b} options as well as object files specified on the command
3284 line. It then processes these inputs and if the @option{-e} option has
3285 been specified it creates a exports file. If the @option{-l} option
3286 has been specified it creates a library file and if the @option{-z} option
3287 has been specified it creates a def file. Any or all of the @option{-e},
3288 @option{-l} and @option{-z} options can be present in one invocation of
3289 dlltool.
3290
3291 When creating a DLL, along with the source for the DLL, it is necessary
3292 to have three other files. @command{dlltool} can help with the creation of
3293 these files.
3294
3295 The first file is a @file{.def} file which specifies which functions are
3296 exported from the DLL, which functions the DLL imports, and so on. This
3297 is a text file and can be created by hand, or @command{dlltool} can be used
3298 to create it using the @option{-z} option. In this case @command{dlltool}
3299 will scan the object files specified on its command line looking for
3300 those functions which have been specially marked as being exported and
3301 put entries for them in the @file{.def} file it creates.
3302
3303 In order to mark a function as being exported from a DLL, it needs to
3304 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
3305 section of the object file. This can be done in C by using the
3306 asm() operator:
3307
3308 @smallexample
3309 asm (".section .drectve");
3310 asm (".ascii \"-export:my_func\"");
3311
3312 int my_func (void) @{ @dots{} @}
3313 @end smallexample
3314
3315 The second file needed for DLL creation is an exports file. This file
3316 is linked with the object files that make up the body of the DLL and it
3317 handles the interface between the DLL and the outside world. This is a
3318 binary file and it can be created by giving the @option{-e} option to
3319 @command{dlltool} when it is creating or reading in a @file{.def} file.
3320
3321 The third file needed for DLL creation is the library file that programs
3322 will link with in order to access the functions in the DLL. This file
3323 can be created by giving the @option{-l} option to dlltool when it
3324 is creating or reading in a @file{.def} file.
3325
3326 @command{dlltool} builds the library file by hand, but it builds the
3327 exports file by creating temporary files containing assembler statements
3328 and then assembling these. The @option{-S} command line option can be
3329 used to specify the path to the assembler that dlltool will use,
3330 and the @option{-f} option can be used to pass specific flags to that
3331 assembler. The @option{-n} can be used to prevent dlltool from deleting
3332 these temporary assembler files when it is done, and if @option{-n} is
3333 specified twice then this will prevent dlltool from deleting the
3334 temporary object files it used to build the library.
3335
3336 Here is an example of creating a DLL from a source file @samp{dll.c} and
3337 also creating a program (from an object file called @samp{program.o})
3338 that uses that DLL:
3339
3340 @smallexample
3341 gcc -c dll.c
3342 dlltool -e exports.o -l dll.lib dll.o
3343 gcc dll.o exports.o -o dll.dll
3344 gcc program.o dll.lib -o program
3345 @end smallexample
3346
3347 @c man end
3348
3349 @c man begin OPTIONS dlltool
3350
3351 The command line options have the following meanings:
3352
3353 @table @env
3354
3355 @item -d @var{filename}
3356 @itemx --input-def @var{filename}
3357 @cindex input .def file
3358 Specifies the name of a @file{.def} file to be read in and processed.
3359
3360 @item -b @var{filename}
3361 @itemx --base-file @var{filename}
3362 @cindex base files
3363 Specifies the name of a base file to be read in and processed. The
3364 contents of this file will be added to the relocation section in the
3365 exports file generated by dlltool.
3366
3367 @item -e @var{filename}
3368 @itemx --output-exp @var{filename}
3369 Specifies the name of the export file to be created by dlltool.
3370
3371 @item -z @var{filename}
3372 @itemx --output-def @var{filename}
3373 Specifies the name of the @file{.def} file to be created by dlltool.
3374
3375 @item -l @var{filename}
3376 @itemx --output-lib @var{filename}
3377 Specifies the name of the library file to be created by dlltool.
3378
3379 @item --export-all-symbols
3380 Treat all global and weak defined symbols found in the input object
3381 files as symbols to be exported. There is a small list of symbols which
3382 are not exported by default; see the @option{--no-default-excludes}
3383 option. You may add to the list of symbols to not export by using the
3384 @option{--exclude-symbols} option.
3385
3386 @item --no-export-all-symbols
3387 Only export symbols explicitly listed in an input @file{.def} file or in
3388 @samp{.drectve} sections in the input object files. This is the default
3389 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3390 attributes in the source code.
3391
3392 @item --exclude-symbols @var{list}
3393 Do not export the symbols in @var{list}. This is a list of symbol names
3394 separated by comma or colon characters. The symbol names should not
3395 contain a leading underscore. This is only meaningful when
3396 @option{--export-all-symbols} is used.
3397
3398 @item --no-default-excludes
3399 When @option{--export-all-symbols} is used, it will by default avoid
3400 exporting certain special symbols. The current list of symbols to avoid
3401 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3402 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3403 to go ahead and export these special symbols. This is only meaningful
3404 when @option{--export-all-symbols} is used.
3405
3406 @item -S @var{path}
3407 @itemx --as @var{path}
3408 Specifies the path, including the filename, of the assembler to be used
3409 to create the exports file.
3410
3411 @item -f @var{options}
3412 @itemx --as-flags @var{options}
3413 Specifies any specific command line options to be passed to the
3414 assembler when building the exports file. This option will work even if
3415 the @option{-S} option is not used. This option only takes one argument,
3416 and if it occurs more than once on the command line, then later
3417 occurrences will override earlier occurrences. So if it is necessary to
3418 pass multiple options to the assembler they should be enclosed in
3419 double quotes.
3420
3421 @item -D @var{name}
3422 @itemx --dll-name @var{name}
3423 Specifies the name to be stored in the @file{.def} file as the name of
3424 the DLL when the @option{-e} option is used. If this option is not
3425 present, then the filename given to the @option{-e} option will be
3426 used as the name of the DLL.
3427
3428 @item -m @var{machine}
3429 @itemx -machine @var{machine}
3430 Specifies the type of machine for which the library file should be
3431 built. @command{dlltool} has a built in default type, depending upon how
3432 it was created, but this option can be used to override that. This is
3433 normally only useful when creating DLLs for an ARM processor, when the
3434 contents of the DLL are actually encode using Thumb instructions.
3435
3436 @item -a
3437 @itemx --add-indirect
3438 Specifies that when @command{dlltool} is creating the exports file it
3439 should add a section which allows the exported functions to be
3440 referenced without using the import library. Whatever the hell that
3441 means!
3442
3443 @item -U
3444 @itemx --add-underscore
3445 Specifies that when @command{dlltool} is creating the exports file it
3446 should prepend an underscore to the names of @emph{all} exported symbols.
3447
3448 @item --add-stdcall-underscore
3449 Specifies that when @command{dlltool} is creating the exports file it
3450 should prepend an underscore to the names of exported @emph{stdcall}
3451 functions. Variable names and non-stdcall function names are not modified.
3452 This option is useful when creating GNU-compatible import libs for third
3453 party DLLs that were built with MS-Windows tools.
3454
3455 @item -k
3456 @itemx --kill-at
3457 Specifies that when @command{dlltool} is creating the exports file it
3458 should not append the string @samp{@@ <number>}. These numbers are
3459 called ordinal numbers and they represent another way of accessing the
3460 function in a DLL, other than by name.
3461
3462 @item -A
3463 @itemx --add-stdcall-alias
3464 Specifies that when @command{dlltool} is creating the exports file it
3465 should add aliases for stdcall symbols without @samp{@@ <number>}
3466 in addition to the symbols with @samp{@@ <number>}.
3467
3468 @item -p
3469 @itemx --ext-prefix-alias @var{prefix}
3470 Causes @command{dlltool} to create external aliases for all DLL
3471 imports with the specified prefix. The aliases are created for both
3472 external and import symbols with no leading underscore.
3473
3474 @item -x
3475 @itemx --no-idata4
3476 Specifies that when @command{dlltool} is creating the exports and library
3477 files it should omit the @code{.idata4} section. This is for compatibility
3478 with certain operating systems.
3479
3480 @item -c
3481 @itemx --no-idata5
3482 Specifies that when @command{dlltool} is creating the exports and library
3483 files it should omit the @code{.idata5} section. This is for compatibility
3484 with certain operating systems.
3485
3486 @item -i
3487 @itemx --interwork
3488 Specifies that @command{dlltool} should mark the objects in the library
3489 file and exports file that it produces as supporting interworking
3490 between ARM and Thumb code.
3491
3492 @item -n
3493 @itemx --nodelete
3494 Makes @command{dlltool} preserve the temporary assembler files it used to
3495 create the exports file. If this option is repeated then dlltool will
3496 also preserve the temporary object files it uses to create the library
3497 file.
3498
3499 @item -t @var{prefix}
3500 @itemx --temp-prefix @var{prefix}
3501 Makes @command{dlltool} use @var{prefix} when constructing the names of
3502 temporary assembler and object files. By default, the temp file prefix
3503 is generated from the pid.
3504
3505 @item -v
3506 @itemx --verbose
3507 Make dlltool describe what it is doing.
3508
3509 @item -h
3510 @itemx --help
3511 Displays a list of command line options and then exits.
3512
3513 @item -V
3514 @itemx --version
3515 Displays dlltool's version number and then exits.
3516
3517 @end table
3518
3519 @c man end
3520
3521 @menu
3522 * def file format:: The format of the dlltool @file{.def} file
3523 @end menu
3524
3525 @node def file format
3526 @section The format of the @command{dlltool} @file{.def} file
3527
3528 A @file{.def} file contains any number of the following commands:
3529
3530 @table @asis
3531
3532 @item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
3533 The result is going to be named @var{name}@code{.exe}.
3534
3535 @item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
3536 The result is going to be named @var{name}@code{.dll}.
3537
3538 @item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )}
3539 @item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
3540 Declares @var{name1} as an exported symbol from the DLL, with optional
3541 ordinal number @var{integer}, or declares @var{name1} as an alias
3542 (forward) of the function @var{external-name} in the DLL
3543 @var{module-name}.
3544
3545 @item @code{IMPORTS ( (} @var{internal-name} @code{=} @var{module-name} @code{.} @var{integer} @code{) | [} @var{internal-name} @code{= ]} @var{module-name} @code{.} @var{external-name} @code{) ) *}
3546 Declares that @var{external-name} or the exported function whose
3547 ordinal number is @var{integer} is to be imported from the file
3548 @var{module-name}. If @var{internal-name} is specified then this is
3549 the name that the imported function will be referred to in the body of
3550 the DLL.
3551
3552 @item @code{DESCRIPTION} @var{string}
3553 Puts @var{string} into the output @file{.exp} file in the
3554 @code{.rdata} section.
3555
3556 @item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3557 @item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3558 Generates @code{--stack} or @code{--heap}
3559 @var{number-reserve},@var{number-commit} in the output @code{.drectve}
3560 section. The linker will see this and act upon it.
3561
3562 @item @code{CODE} @var{attr} @code{+}
3563 @item @code{DATA} @var{attr} @code{+}
3564 @item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
3565 Generates @code{--attr} @var{section-name} @var{attr} in the output
3566 @code{.drectve} section, where @var{attr} is one of @code{READ},
3567 @code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
3568 this and act upon it.
3569
3570 @end table
3571
3572 @ignore
3573 @c man begin SEEALSO dlltool
3574 The Info pages for @file{binutils}.
3575 @c man end
3576 @end ignore
3577
3578 @node readelf
3579 @chapter readelf
3580
3581 @cindex ELF file information
3582 @kindex readelf
3583
3584 @c man title readelf Displays information about ELF files.
3585
3586 @smallexample
3587 @c man begin SYNOPSIS readelf
3588 readelf [@option{-a}|@option{--all}]
3589 [@option{-h}|@option{--file-header}]
3590 [@option{-l}|@option{--program-headers}|@option{--segments}]
3591 [@option{-S}|@option{--section-headers}|@option{--sections}]
3592 [@option{-g}|@option{--section-groups}]
3593 [@option{-t}|@option{--section-details}]
3594 [@option{-e}|@option{--headers}]
3595 [@option{-s}|@option{--syms}|@option{--symbols}]
3596 [@option{-n}|@option{--notes}]
3597 [@option{-r}|@option{--relocs}]
3598 [@option{-u}|@option{--unwind}]
3599 [@option{-d}|@option{--dynamic}]
3600 [@option{-V}|@option{--version-info}]
3601 [@option{-A}|@option{--arch-specific}]
3602 [@option{-D}|@option{--use-dynamic}]
3603 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
3604 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
3605 [@option{-w[liaprmfFsoR]}|
3606 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
3607 [@option{-I}|@option{-histogram}]
3608 [@option{-v}|@option{--version}]
3609 [@option{-W}|@option{--wide}]
3610 [@option{-H}|@option{--help}]
3611 @var{elffile}@dots{}
3612 @c man end
3613 @end smallexample
3614
3615 @c man begin DESCRIPTION readelf
3616
3617 @command{readelf} displays information about one or more ELF format object
3618 files. The options control what particular information to display.
3619
3620 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3621 64-bit ELF files are supported, as are archives containing ELF files.
3622
3623 This program performs a similar function to @command{objdump} but it
3624 goes into more detail and it exists independently of the @sc{bfd}
3625 library, so if there is a bug in @sc{bfd} then readelf will not be
3626 affected.
3627
3628 @c man end
3629
3630 @c man begin OPTIONS readelf
3631
3632 The long and short forms of options, shown here as alternatives, are
3633 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3634 given.
3635
3636 @table @env
3637 @item -a
3638 @itemx --all
3639 Equivalent to specifying @option{--file-header},
3640 @option{--program-headers}, @option{--sections}, @option{--symbols},
3641 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3642 @option{--version-info}.
3643
3644 @item -h
3645 @itemx --file-header
3646 @cindex ELF file header information
3647 Displays the information contained in the ELF header at the start of the
3648 file.
3649
3650 @item -l
3651 @itemx --program-headers
3652 @itemx --segments
3653 @cindex ELF program header information
3654 @cindex ELF segment information
3655 Displays the information contained in the file's segment headers, if it
3656 has any.
3657
3658 @item -S
3659 @itemx --sections
3660 @itemx --section-headers
3661 @cindex ELF section information
3662 Displays the information contained in the file's section headers, if it
3663 has any.
3664
3665 @item -g
3666 @itemx --section-groups
3667 @cindex ELF section group information
3668 Displays the information contained in the file's section groups, if it
3669 has any.
3670
3671 @item -t
3672 @itemx --section-details
3673 @cindex ELF section information
3674 Displays the detailed section information. Implies @option{-S}.
3675
3676 @item -s
3677 @itemx --symbols
3678 @itemx --syms
3679 @cindex ELF symbol table information
3680 Displays the entries in symbol table section of the file, if it has one.
3681
3682 @item -e
3683 @itemx --headers
3684 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3685
3686 @item -n
3687 @itemx --notes
3688 @cindex ELF notes
3689 Displays the contents of the NOTE segments and/or sections, if any.
3690
3691 @item -r
3692 @itemx --relocs
3693 @cindex ELF reloc information
3694 Displays the contents of the file's relocation section, if it has one.
3695
3696 @item -u
3697 @itemx --unwind
3698 @cindex unwind information
3699 Displays the contents of the file's unwind section, if it has one. Only
3700 the unwind sections for IA64 ELF files are currently supported.
3701
3702 @item -d
3703 @itemx --dynamic
3704 @cindex ELF dynamic section information
3705 Displays the contents of the file's dynamic section, if it has one.
3706
3707 @item -V
3708 @itemx --version-info
3709 @cindex ELF version sections informations
3710 Displays the contents of the version sections in the file, it they
3711 exist.
3712
3713 @item -A
3714 @itemx --arch-specific
3715 Displays architecture-specific information in the file, if there
3716 is any.
3717
3718 @item -D
3719 @itemx --use-dynamic
3720 When displaying symbols, this option makes @command{readelf} use the
3721 symbol table in the file's dynamic section, rather than the one in the
3722 symbols section.
3723
3724 @item -x <number or name>
3725 @itemx --hex-dump=<number or name>
3726 Displays the contents of the indicated section as a hexadecimal dump.
3727 A number identifies a particular section by index in the section table;
3728 any other string identifies all sections with that name in the object file.
3729
3730 @item -p <number or name>
3731 @itemx --string-dump=<number or name>
3732 Displays the contents of the indicated section as printable strings.
3733 A number identifies a particular section by index in the section table;
3734 any other string identifies all sections with that name in the object file.
3735
3736 @item -w[liaprmfFsoR]
3737 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
3738 Displays the contents of the debug sections in the file, if any are
3739 present. If one of the optional letters or words follows the switch
3740 then only data found in those specific sections will be dumped.
3741
3742 @item -I
3743 @itemx --histogram
3744 Display a histogram of bucket list lengths when displaying the contents
3745 of the symbol tables.
3746
3747 @item -v
3748 @itemx --version
3749 Display the version number of readelf.
3750
3751 @item -W
3752 @itemx --wide
3753 Don't break output lines to fit into 80 columns. By default
3754 @command{readelf} breaks section header and segment listing lines for
3755 64-bit ELF files, so that they fit into 80 columns. This option causes
3756 @command{readelf} to print each section header resp. each segment one a
3757 single line, which is far more readable on terminals wider than 80 columns.
3758
3759 @item -H
3760 @itemx --help
3761 Display the command line options understood by @command{readelf}.
3762
3763 @end table
3764
3765 @c man end
3766
3767 @ignore
3768 @c man begin SEEALSO readelf
3769 objdump(1), and the Info entries for @file{binutils}.
3770 @c man end
3771 @end ignore
3772
3773 @node Common Options
3774 @chapter Common Options
3775
3776 The following command-line options are supported by all of the
3777 programs described in this manual.
3778
3779 @c man begin OPTIONS
3780 @table @env
3781 @include at-file.texi
3782 @c man end
3783
3784 @item --help
3785 Display the command-line options supported by the program.
3786
3787 @item --version
3788 Display the version number of the program.
3789
3790 @c man begin OPTIONS
3791 @end table
3792 @c man end
3793
3794 @node Selecting The Target System
3795 @chapter Selecting the Target System
3796
3797 You can specify two aspects of the target system to the @sc{gnu}
3798 binary file utilities, each in several ways:
3799
3800 @itemize @bullet
3801 @item
3802 the target
3803
3804 @item
3805 the architecture
3806 @end itemize
3807
3808 In the following summaries, the lists of ways to specify values are in
3809 order of decreasing precedence. The ways listed first override those
3810 listed later.
3811
3812 The commands to list valid values only list the values for which the
3813 programs you are running were configured. If they were configured with
3814 @option{--enable-targets=all}, the commands list most of the available
3815 values, but a few are left out; not all targets can be configured in at
3816 once because some of them can only be configured @dfn{native} (on hosts
3817 with the same type as the target system).
3818
3819 @menu
3820 * Target Selection::
3821 * Architecture Selection::
3822 @end menu
3823
3824 @node Target Selection
3825 @section Target Selection
3826
3827 A @dfn{target} is an object file format. A given target may be
3828 supported for multiple architectures (@pxref{Architecture Selection}).
3829 A target selection may also have variations for different operating
3830 systems or architectures.
3831
3832 The command to list valid target values is @samp{objdump -i}
3833 (the first column of output contains the relevant information).
3834
3835 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3836 @samp{a.out-sunos-big}.
3837
3838 You can also specify a target using a configuration triplet. This is
3839 the same sort of name that is passed to @file{configure} to specify a
3840 target. When you use a configuration triplet as an argument, it must be
3841 fully canonicalized. You can see the canonical version of a triplet by
3842 running the shell script @file{config.sub} which is included with the
3843 sources.
3844
3845 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3846 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3847
3848 @subheading @command{objdump} Target
3849
3850 Ways to specify:
3851
3852 @enumerate
3853 @item
3854 command line option: @option{-b} or @option{--target}
3855
3856 @item
3857 environment variable @code{GNUTARGET}
3858
3859 @item
3860 deduced from the input file
3861 @end enumerate
3862
3863 @subheading @command{objcopy} and @command{strip} Input Target
3864
3865 Ways to specify:
3866
3867 @enumerate
3868 @item
3869 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3870
3871 @item
3872 environment variable @code{GNUTARGET}
3873
3874 @item
3875 deduced from the input file
3876 @end enumerate
3877
3878 @subheading @command{objcopy} and @command{strip} Output Target
3879
3880 Ways to specify:
3881
3882 @enumerate
3883 @item
3884 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3885
3886 @item
3887 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3888
3889 @item
3890 environment variable @code{GNUTARGET}
3891
3892 @item
3893 deduced from the input file
3894 @end enumerate
3895
3896 @subheading @command{nm}, @command{size}, and @command{strings} Target
3897
3898 Ways to specify:
3899
3900 @enumerate
3901 @item
3902 command line option: @option{--target}
3903
3904 @item
3905 environment variable @code{GNUTARGET}
3906
3907 @item
3908 deduced from the input file
3909 @end enumerate
3910
3911 @node Architecture Selection
3912 @section Architecture Selection
3913
3914 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3915 to run. Its name may contain a colon, separating the name of the
3916 processor family from the name of the particular @sc{cpu}.
3917
3918 The command to list valid architecture values is @samp{objdump -i} (the
3919 second column contains the relevant information).
3920
3921 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3922
3923 @subheading @command{objdump} Architecture
3924
3925 Ways to specify:
3926
3927 @enumerate
3928 @item
3929 command line option: @option{-m} or @option{--architecture}
3930
3931 @item
3932 deduced from the input file
3933 @end enumerate
3934
3935 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3936
3937 Ways to specify:
3938
3939 @enumerate
3940 @item
3941 deduced from the input file
3942 @end enumerate
3943
3944 @node Reporting Bugs
3945 @chapter Reporting Bugs
3946 @cindex bugs
3947 @cindex reporting bugs
3948
3949 Your bug reports play an essential role in making the binary utilities
3950 reliable.
3951
3952 Reporting a bug may help you by bringing a solution to your problem, or
3953 it may not. But in any case the principal function of a bug report is
3954 to help the entire community by making the next version of the binary
3955 utilities work better. Bug reports are your contribution to their
3956 maintenance.
3957
3958 In order for a bug report to serve its purpose, you must include the
3959 information that enables us to fix the bug.
3960
3961 @menu
3962 * Bug Criteria:: Have you found a bug?
3963 * Bug Reporting:: How to report bugs
3964 @end menu
3965
3966 @node Bug Criteria
3967 @section Have You Found a Bug?
3968 @cindex bug criteria
3969
3970 If you are not sure whether you have found a bug, here are some guidelines:
3971
3972 @itemize @bullet
3973 @cindex fatal signal
3974 @cindex crash
3975 @item
3976 If a binary utility gets a fatal signal, for any input whatever, that is
3977 a bug. Reliable utilities never crash.
3978
3979 @cindex error on valid input
3980 @item
3981 If a binary utility produces an error message for valid input, that is a
3982 bug.
3983
3984 @item
3985 If you are an experienced user of binary utilities, your suggestions for
3986 improvement are welcome in any case.
3987 @end itemize
3988
3989 @node Bug Reporting
3990 @section How to Report Bugs
3991 @cindex bug reports
3992 @cindex bugs, reporting
3993
3994 A number of companies and individuals offer support for @sc{gnu}
3995 products. If you obtained the binary utilities from a support
3996 organization, we recommend you contact that organization first.
3997
3998 You can find contact information for many support companies and
3999 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
4000 distribution.
4001
4002 @ifset BUGURL
4003 In any event, we also recommend that you send bug reports for the binary
4004 utilities to @value{BUGURL}.
4005 @end ifset
4006
4007 The fundamental principle of reporting bugs usefully is this:
4008 @strong{report all the facts}. If you are not sure whether to state a
4009 fact or leave it out, state it!
4010
4011 Often people omit facts because they think they know what causes the
4012 problem and assume that some details do not matter. Thus, you might
4013 assume that the name of a file you use in an example does not matter.
4014 Well, probably it does not, but one cannot be sure. Perhaps the bug is
4015 a stray memory reference which happens to fetch from the location where
4016 that pathname is stored in memory; perhaps, if the pathname were
4017 different, the contents of that location would fool the utility into
4018 doing the right thing despite the bug. Play it safe and give a
4019 specific, complete example. That is the easiest thing for you to do,
4020 and the most helpful.
4021
4022 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
4023 it is new to us. Therefore, always write your bug reports on the assumption
4024 that the bug has not been reported previously.
4025
4026 Sometimes people give a few sketchy facts and ask, ``Does this ring a
4027 bell?'' This cannot help us fix a bug, so it is basically useless. We
4028 respond by asking for enough details to enable us to investigate.
4029 You might as well expedite matters by sending them to begin with.
4030
4031 To enable us to fix the bug, you should include all these things:
4032
4033 @itemize @bullet
4034 @item
4035 The version of the utility. Each utility announces it if you start it
4036 with the @option{--version} argument.
4037
4038 Without this, we will not know whether there is any point in looking for
4039 the bug in the current version of the binary utilities.
4040
4041 @item
4042 Any patches you may have applied to the source, including any patches
4043 made to the @code{BFD} library.
4044
4045 @item
4046 The type of machine you are using, and the operating system name and
4047 version number.
4048
4049 @item
4050 What compiler (and its version) was used to compile the utilities---e.g.
4051 ``@code{gcc-2.7}''.
4052
4053 @item
4054 The command arguments you gave the utility to observe the bug. To
4055 guarantee you will not omit something important, list them all. A copy
4056 of the Makefile (or the output from make) is sufficient.
4057
4058 If we were to try to guess the arguments, we would probably guess wrong
4059 and then we might not encounter the bug.
4060
4061 @item
4062 A complete input file, or set of input files, that will reproduce the
4063 bug. If the utility is reading an object file or files, then it is
4064 generally most helpful to send the actual object files.
4065
4066 If the source files were produced exclusively using @sc{gnu} programs
4067 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
4068 may be OK to send the source files rather than the object files. In
4069 this case, be sure to say exactly what version of @command{gcc}, or
4070 whatever, was used to produce the object files. Also say how
4071 @command{gcc}, or whatever, was configured.
4072
4073 @item
4074 A description of what behavior you observe that you believe is
4075 incorrect. For example, ``It gets a fatal signal.''
4076
4077 Of course, if the bug is that the utility gets a fatal signal, then we
4078 will certainly notice it. But if the bug is incorrect output, we might
4079 not notice unless it is glaringly wrong. You might as well not give us
4080 a chance to make a mistake.
4081
4082 Even if the problem you experience is a fatal signal, you should still
4083 say so explicitly. Suppose something strange is going on, such as your
4084 copy of the utility is out of sync, or you have encountered a bug in
4085 the C library on your system. (This has happened!) Your copy might
4086 crash and ours would not. If you told us to expect a crash, then when
4087 ours fails to crash, we would know that the bug was not happening for
4088 us. If you had not told us to expect a crash, then we would not be able
4089 to draw any conclusion from our observations.
4090
4091 @item
4092 If you wish to suggest changes to the source, send us context diffs, as
4093 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
4094 option. Always send diffs from the old file to the new file. If you
4095 wish to discuss something in the @command{ld} source, refer to it by
4096 context, not by line number.
4097
4098 The line numbers in our development sources will not match those in your
4099 sources. Your line numbers would convey no useful information to us.
4100 @end itemize
4101
4102 Here are some things that are not necessary:
4103
4104 @itemize @bullet
4105 @item
4106 A description of the envelope of the bug.
4107
4108 Often people who encounter a bug spend a lot of time investigating
4109 which changes to the input file will make the bug go away and which
4110 changes will not affect it.
4111
4112 This is often time consuming and not very useful, because the way we
4113 will find the bug is by running a single example under the debugger
4114 with breakpoints, not by pure deduction from a series of examples.
4115 We recommend that you save your time for something else.
4116
4117 Of course, if you can find a simpler example to report @emph{instead}
4118 of the original one, that is a convenience for us. Errors in the
4119 output will be easier to spot, running under the debugger will take
4120 less time, and so on.
4121
4122 However, simplification is not vital; if you do not want to do this,
4123 report the bug anyway and send us the entire test case you used.
4124
4125 @item
4126 A patch for the bug.
4127
4128 A patch for the bug does help us if it is a good one. But do not omit
4129 the necessary information, such as the test case, on the assumption that
4130 a patch is all we need. We might see problems with your patch and decide
4131 to fix the problem another way, or we might not understand it at all.
4132
4133 Sometimes with programs as complicated as the binary utilities it is
4134 very hard to construct an example that will make the program follow a
4135 certain path through the code. If you do not send us the example, we
4136 will not be able to construct one, so we will not be able to verify that
4137 the bug is fixed.
4138
4139 And if we cannot understand what bug you are trying to fix, or why your
4140 patch should be an improvement, we will not install it. A test case will
4141 help us to understand.
4142
4143 @item
4144 A guess about what the bug is or what it depends on.
4145
4146 Such guesses are usually wrong. Even we cannot guess right about such
4147 things without first using the debugger to find the facts.
4148 @end itemize
4149
4150 @include fdl.texi
4151
4152 @node Binutils Index
4153 @unnumbered Binutils Index
4154
4155 @printindex cp
4156
4157 @bye