* arm-dis.c (print_insn): Check for a symtab that exists but is empty.
[deliverable/binutils-gdb.git] / binutils / doc / binutils.texi
... / ...
CommitLineData
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
12START-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
30END-INFO-DIR-ENTRY
31@end format
32@end ifinfo
33
34@copying
35@c man begin COPYRIGHT
36Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
372000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
38
39Permission is granted to copy, distribute and/or modify this document
40under the terms of the GNU Free Documentation License, Version 1.1
41or any later version published by the Free Software Foundation;
42with no Invariant Sections, with no Front-Cover Texts, and with no
43Back-Cover Texts. A copy of the license is included in the
44section 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
83Copyright @copyright{} 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
842000, 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
100This brief manual contains documentation for the @sc{gnu} binary
101utilities
102@ifset VERSION_PACKAGE
103@value{VERSION_PACKAGE}
104@end ifset
105version @value{VERSION}:
106
107@iftex
108@table @code
109@item ar
110Create, modify, and extract from archives
111
112@item nm
113List symbols from object files
114
115@item objcopy
116Copy and translate object files
117
118@item objdump
119Display information from object files
120
121@item ranlib
122Generate index to archive contents
123
124@item readelf
125Display the contents of ELF format files.
126
127@item size
128List file section sizes and total size
129
130@item strings
131List printable strings from files
132
133@item strip
134Discard symbols
135
136@item c++filt
137Demangle encoded C++ symbols (on MS-DOS, this program is named
138@code{cxxfilt})
139
140@item addr2line
141Convert addresses into file names and line numbers
142
143@item nlmconv
144Convert object code into a Netware Loadable Module
145
146@item windres
147Manipulate Windows resources
148
149@item windmc
150Genertor for Windows message resources
151
152@item dlltool
153Create the files needed to build and use Dynamic Link Libraries
154@end table
155@end iftex
156
157This document is distributed under the terms of the GNU Free
158Documentation License. A copy of the license is included in the
159section 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
195ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
196ar -M [ <mri-script ]
197@end smallexample
198
199@c man begin DESCRIPTION ar
200
201The @sc{gnu} @command{ar} program creates, modifies, and extracts from
202archives. An @dfn{archive} is a single file holding a collection of
203other files in a structure that makes it possible to retrieve
204the original individual files (called @dfn{members} of the archive).
205
206The original files' contents, mode (permissions), timestamp, owner, and
207group are preserved in the archive, and can be restored on
208extraction.
209
210@cindex name length
211@sc{gnu} @command{ar} can maintain archives whose members have names of any
212length; however, depending on how @command{ar} is configured on your
213system, a limit on member-name length may be imposed for compatibility
214with archive formats maintained with other tools. If it exists, the
215limit is often 15 characters (typical of formats related to a.out) or 16
216characters (typical of formats related to coff).
217
218@cindex libraries
219@command{ar} is considered a binary utility because archives of this sort
220are most often used as @dfn{libraries} holding commonly needed
221subroutines.
222
223@cindex symbol index
224@command{ar} creates an index to the symbols defined in relocatable
225object modules in the archive when you specify the modifier @samp{s}.
226Once created, this index is updated in the archive whenever @command{ar}
227makes a change to its contents (save for the @samp{q} update operation).
228An archive with such an index speeds up linking to the library, and
229allows routines in the library to call each other without regard to
230their placement in the archive.
231
232You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
233table. 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
239facilities. You can control its activity using command-line options,
240like the different varieties of @command{ar} on Unix systems; or, if you
241specify the single command-line option @option{-M}, you can control it
242with a script supplied via standard input, like the MRI ``librarian''
243program.
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
258ar [@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}
263When you use @command{ar} in the Unix style, @command{ar} insists on at least two
264arguments 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
268Most operations can also accept further @var{member} arguments,
269specifying 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
274flags @var{mod} in any order, within the first command-line argument.
275
276If you wish, you may begin the first command-line argument with a
277dash.
278
279@cindex operations on archive
280The @var{p} keyletter specifies what operation to execute; it may be
281any 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
287be deleted as @var{member}@dots{}; the archive is untouched if you
288specify no files to delete.
289
290If you specify the @samp{v} modifier, @command{ar} lists each module
291as it is deleted.
292
293@item m
294@cindex moving in archive
295Use this operation to @emph{move} members in an archive.
296
297The ordering of members in an archive can make a difference in how
298programs are linked using the library, if a symbol is defined in more
299than one member.
300
301If 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;
303you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
304specified place instead.
305
306@item p
307@cindex printing from archive
308@emph{Print} the specified members of the archive, to the standard
309output file. If the @samp{v} modifier is specified, show the member
310name before copying its contents to standard output.
311
312If you specify no @var{member} arguments, all the files in the archive are
313printed.
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
320The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
321operation; new members are always placed at the end of the archive.
322
323The modifier @samp{v} makes @command{ar} list each file as it is appended.
324
325Since the point of this operation is speed, the archive's symbol table
326index 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
329However, too many different systems assume quick append rebuilds the
330index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
331
332@item r
333@cindex replacement in archive
334Insert the files @var{member}@dots{} into @var{archive} (with
335@emph{replacement}). This operation differs from @samp{q} in that any
336previously existing members are deleted if their names match those being
337added.
338
339If one of the files named in @var{member}@dots{} does not exist, @command{ar}
340displays an error message, and leaves undisturbed any existing members
341of the archive matching that name.
342
343By default, new members are added at the end of the file; but you may
344use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
345placement relative to some existing member.
346
347The modifier @samp{v} used with this operation elicits a line of
348output 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
350deleted) or replaced.
351
352@item t
353@cindex contents of archive
354Display a @emph{table} listing the contents of @var{archive}, or those
355of the files listed in @var{member}@dots{} that are present in the
356archive. Normally only the member name is shown; if you also want to
357see the modes (permissions), timestamp, owner, group, and size, you can
358request that by also specifying the @samp{v} modifier.
359
360If you do not specify a @var{member}, all files in the archive
361are listed.
362
363@cindex repeated names in archive
364@cindex name duplication in archive
365If there is more than one file with the same name (say, @samp{fie}) in
366an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
367first instance; to see them all, you must ask for a complete
368listing---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
375use the @samp{v} modifier with this operation, to request that
376@command{ar} list each name as it extracts it.
377
378If you do not specify a @var{member}, all files in the archive
379are extracted.
380
381@end table
382
383A number of modifiers (@var{mod}) may immediately follow the @var{p}
384keyletter, to specify variations on an operation's behavior:
385
386@table @samp
387@item a
388@cindex relative placement in archive
389Add new files @emph{after} an existing member of the
390archive. If you use the modifier @samp{a}, the name of an existing archive
391member must be present as the @var{relpos} argument, before the
392@var{archive} specification.
393
394@item b
395Add new files @emph{before} an existing member of the
396archive. If you use the modifier @samp{b}, the name of an existing archive
397member 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
403created if it did not exist, when you request an update. But a warning is
404issued unless you specify in advance that you expect to create it, by
405using this modifier.
406
407@item f
408Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
409names of any length. This will cause it to create archives which are
410not compatible with the native @command{ar} program on some systems. If
411this is a concern, the @samp{f} modifier may be used to truncate file
412names when putting them in the archive.
413
414@item i
415Insert new files @emph{before} an existing member of the
416archive. If you use the modifier @samp{i}, the name of an existing archive
417member must be present as the @var{relpos} argument, before the
418@var{archive} specification. (same as @samp{b}).
419
420@item l
421This 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
426Uses the @var{count} parameter. This is used if there are multiple
427entries 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
432Preserve the @emph{original} dates of members when extracting them. If
433you do not specify this modifier, files extracted from the archive
434are stamped with the time of extraction.
435
436@item P
437Use 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
439are not POSIX complaint), but other archive creators can. This option
440will cause @sc{gnu} @command{ar} to match file names using a complete path
441name, which can be convenient when extracting a single file from an
442archive created by another tool.
443
444@item s
445@cindex writing archive index
446Write an object-file index into the archive, or update an existing one,
447even if no other change is made to the archive. You may use this modifier
448flag either with any operation, or alone. Running @samp{ar s} on an
449archive is equivalent to running @samp{ranlib} on it.
450
451@item S
452@cindex not writing archive index
453Do not generate an archive symbol table. This can speed up building a
454large library in several steps. The resulting archive can not be used
455with 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
461Normally, @samp{ar r}@dots{} inserts all files
462listed into the archive. If you would like to insert @emph{only} those
463of the files you list that are newer than existing members of the same
464names, use this modifier. The @samp{u} modifier is allowed only for the
465operation @samp{r} (replace). In particular, the combination @samp{qu} is
466not allowed, since checking the timestamps would lose any speed
467advantage from the operation @samp{q}.
468
469@item v
470This modifier requests the @emph{verbose} version of an operation. Many
471operations display additional information, such as filenames processed,
472when the modifier @samp{v} is appended.
473
474@item V
475This modifier shows the version number of @command{ar}.
476@end table
477
478@command{ar} ignores an initial option spelt @samp{-X32_64}, for
479compatibility with AIX. The behaviour produced by this option is the
480default 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}
482which is the default for AIX @command{ar}.
483
484@c man end
485
486@ignore
487@c man begin SEEALSO ar
488nm(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
496ar -M [ <@var{script} ]
497@end smallexample
498
499@cindex MRI compatibility, @command{ar}
500@cindex scripts, @command{ar}
501If you use the single command-line option @samp{-M} with @command{ar}, you
502can control its operation with a rudimentary command language. This
503form of @command{ar} operates interactively if standard input is coming
504directly from a terminal. During interactive use, @command{ar} prompts for
505input (the prompt is @samp{AR >}), and continues executing even after
506errors. If you redirect standard input to a script file, no prompts are
507issued, and @command{ar} abandons execution (with a nonzero exit code)
508on any error.
509
510The @command{ar} command language is @emph{not} designed to be equivalent
511to the command-line options; in fact, it provides somewhat less control
512over archives. The only purpose of the command language is to ease the
513transition to @sc{gnu} @command{ar} for developers who already have scripts
514written for the MRI ``librarian'' program.
515
516The syntax for the @command{ar} command language is straightforward:
517@itemize @bullet
518@item
519commands are recognized in upper or lower case; for example, @code{LIST}
520is the same as @code{list}. In the following descriptions, commands are
521shown in upper case for clarity.
522
523@item
524a single command may appear on each line; it is the first word on the
525line.
526
527@item
528empty lines are allowed, and have no effect.
529
530@item
531comments are allowed; text after either of the characters @samp{*}
532or @samp{;} is ignored.
533
534@item
535Whenever you use a list of names as part of the argument to an @command{ar}
536command, you can separate the individual names with either commas or
537blanks. Commas are shown in the explanations below, for clarity.
538
539@item
540@samp{+} is used as a line continuation character; if @samp{+} appears
541at the end of a line, the text on the following line is considered part
542of the current command.
543@end itemize
544
545Here 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
549a temporary file required for most of the other commands.
550
551@code{SAVE} commits the changes so far specified by the script. Prior
552to @code{SAVE}, commands affect only the temporary copy of the current
553archive.
554
555@table @code
556@item ADDLIB @var{archive}
557@itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
558Add all the contents of @var{archive} (or, if specified, each named
559@var{module} from @var{archive}) to the current archive.
560
561Requires 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..."
566Add each named @var{member} as a module in the current archive.
567
568Requires prior use of @code{OPEN} or @code{CREATE}.
569
570@item CLEAR
571Discard the contents of the current archive, canceling the effect of
572any operations since the last @code{SAVE}. May be executed (with no
573effect) even if no current archive is specified.
574
575@item CREATE @var{archive}
576Creates an archive, and makes it the current archive (required for many
577other commands). The new archive is created with a temporary name; it
578is not actually saved as @var{archive} until you use @code{SAVE}.
579You can overwrite existing archives; similarly, the contents of any
580existing file named @var{archive} will not be destroyed until @code{SAVE}.
581
582@item DELETE @var{module}, @var{module}, @dots{} @var{module}
583Delete each listed @var{module} from the current archive; equivalent to
584@samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
585
586Requires 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}
590List each named @var{module} present in @var{archive}. The separate
591command @code{VERBOSE} specifies the form of the output: when verbose
592output 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
596Output normally goes to the standard output stream; however, if you
597specify @var{outputfile} as a final argument, @command{ar} directs the
598output to that file.
599
600@item END
601Exit from @command{ar}, with a @code{0} exit code to indicate successful
602completion. This command does not save the output file; if you have
603changed the current archive since the last @code{SAVE} command, those
604changes are lost.
605
606@item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
607Extract each named @var{module} from the current archive, writing them
608into the current directory as separate files. Equivalent to @samp{ar -x
609@var{archive} @var{module}@dots{}}.
610
611Requires 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
621Display full contents of the current archive, in ``verbose'' style
622regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
623tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
624enhancement, rather than present for MRI compatibility.)
625
626Requires prior use of @code{OPEN} or @code{CREATE}.
627
628@item OPEN @var{archive}
629Opens an existing archive for use as the current archive (required for
630many other commands). Any changes as the result of subsequent commands
631will not actually affect @var{archive} until you next use @code{SAVE}.
632
633@item REPLACE @var{module}, @var{module}, @dots{} @var{module}
634In the current archive, replace each existing @var{module} (named in
635the @code{REPLACE} arguments) from files in the current working directory.
636To execute this command without errors, both the file, and the module in
637the current archive, must exist.
638
639Requires prior use of @code{OPEN} or @code{CREATE}.
640
641@item VERBOSE
642Toggle an internal flag governing the output from @code{DIRECTORY}.
643When the flag is on, @code{DIRECTORY} output matches output from
644@samp{ar -tv }@dots{}.
645
646@item SAVE
647Commit your changes to the current archive, and actually save it as a
648file with the name specified in the last @code{CREATE} or @code{OPEN}
649command.
650
651Requires 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
660The @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
673nm [@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{}.
688If no object files are listed as arguments, @command{nm} assumes the file
689@file{a.out}.
690
691For each symbol, @command{nm} shows:
692
693@itemize @bullet
694@item
695The symbol value, in the radix selected by options (see below), or
696hexadecimal by default.
697
698@item
699The symbol type. At least the following types are used; others are, as
700well, depending on the object file format. If lowercase, the symbol is
701local; 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
707The symbol's value is absolute, and will not be changed by further
708linking.
709
710@item B
711@itemx b
712The symbol is in the uninitialized data section (known as BSS).
713
714@item C
715The symbol is common. Common symbols are uninitialized data. When
716linking, multiple common symbols may appear with the same name. If the
717symbol is defined anywhere, the common symbols are treated as undefined
718references.
719@ifclear man
720For more details on common symbols, see the discussion of
721--warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
722@end ifclear
723
724@item D
725@itemx d
726The symbol is in the initialized data section.
727
728@item G
729@itemx g
730The symbol is in an initialized data section for small objects. Some
731object file formats permit more efficient access to small data objects,
732such as a global int variable as opposed to a large global array.
733
734@item I
735The symbol is an indirect reference to another symbol. This is a @sc{gnu}
736extension to the a.out object file format which is rarely used.
737
738@item i
739The symbol is in a section specific to the implementation of DLLs.
740
741@item N
742The symbol is a debugging symbol.
743
744@item p
745The symbols is in a stack unwind section.
746
747@item R
748@itemx r
749The symbol is in a read only data section.
750
751@item S
752@itemx s
753The symbol is in an uninitialized data section for small objects.
754
755@item T
756@itemx t
757The symbol is in the text (code) section.
758
759@item U
760The symbol is undefined.
761
762@item V
763@itemx v
764The symbol is a weak object. When a weak defined symbol is linked with
765a normal defined symbol, the normal defined symbol is used with no error.
766When a weak undefined symbol is linked and the symbol is not defined,
767the value of the weak symbol becomes zero with no error. On some
768systems, uppercase indicates that a default value has been specified.
769
770@item W
771@itemx w
772The symbol is a weak symbol that has not been specifically tagged as a
773weak object symbol. When a weak defined symbol is linked with a normal
774defined symbol, the normal defined symbol is used with no error.
775When a weak undefined symbol is linked and the symbol is not defined,
776the value of the symbol is determined in a system-specific manner without
777error. On some systems, uppercase indicates that a default value has been
778specified.
779
780@item -
781The symbol is a stabs symbol in an a.out object file. In this case, the
782next values printed are the stabs other field, the stabs desc field, and
783the stab type. Stabs symbols are used to hold debugging information.
784@ifclear man
785For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
786``stabs'' debug format}.
787@end ifclear
788
789@item ?
790The symbol type is unknown, or object file format specific.
791@end table
792
793@item
794The symbol name.
795@end itemize
796
797@c man end
798
799@c man begin OPTIONS nm
800The long and short forms of options, shown here as alternatives, are
801equivalent.
802
803@table @env
804@item -A
805@itemx -o
806@itemx --print-file-name
807@cindex input file name
808@cindex file name
809@cindex source file name
810Precede each symbol by the name of the input file (or archive member)
811in which it was found, rather than identifying the input file once only,
812before all of its symbols.
813
814@item -a
815@itemx --debug-syms
816@cindex debugging symbols
817Display all symbols, even debugger-only symbols; normally these are not
818listed.
819
820@item -B
821@cindex @command{nm} format
822@cindex @command{nm} compatibility
823The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
824
825@item -C
826@itemx --demangle[=@var{style}]
827@cindex demangling in nm
828Decode (@dfn{demangle}) low-level symbol names into user-level names.
829Besides removing any initial underscore prepended by the system, this
830makes C++ function names readable. Different compilers have different
831mangling styles. The optional demangling style argument can be used to
832choose an appropriate demangling style for your compiler. @xref{c++filt},
833for more information on demangling.
834
835@item --no-demangle
836Do not demangle low-level symbol names. This is the default.
837
838@item -D
839@itemx --dynamic
840@cindex dynamic symbols
841Display the dynamic symbols rather than the normal symbols. This is
842only meaningful for dynamic objects, such as certain types of shared
843libraries.
844
845@item -f @var{format}
846@itemx --format=@var{format}
847@cindex @command{nm} format
848@cindex @command{nm} compatibility
849Use the output format @var{format}, which can be @code{bsd},
850@code{sysv}, or @code{posix}. The default is @code{bsd}.
851Only the first character of @var{format} is significant; it can be
852either upper or lower case.
853
854@item -g
855@itemx --extern-only
856@cindex external symbols
857Display only external symbols.
858
859@item -l
860@itemx --line-numbers
861@cindex symbol line numbers
862For each symbol, use debugging information to try to find a filename and
863line number. For a defined symbol, look for the line number of the
864address of the symbol. For an undefined symbol, look for the line
865number of a relocation entry which refers to the symbol. If line number
866information can be found, print it after the other symbol information.
867
868@item -n
869@itemx -v
870@itemx --numeric-sort
871Sort symbols numerically by their addresses, rather than alphabetically
872by their names.
873
874@item -p
875@itemx --no-sort
876@cindex sorting symbols
877Do not bother to sort the symbols in any order; print them in the order
878encountered.
879
880@item -P
881@itemx --portability
882Use the POSIX.2 standard output format instead of the default format.
883Equivalent to @samp{-f posix}.
884
885@item -S
886@itemx --print-size
887Print size, not the value, of defined symbols for the @code{bsd} output format.
888
889@item -s
890@itemx --print-armap
891@cindex symbol index, listing
892When listing symbols from archive members, include the index: a mapping
893(stored in the archive by @command{ar} or @command{ranlib}) of which modules
894contain definitions for which names.
895
896@item -r
897@itemx --reverse-sort
898Reverse the order of the sort (whether numeric or alphabetic); let the
899last come first.
900
901@item --size-sort
902Sort symbols by size. The size is computed as the difference between
903the value of the symbol and the value of the symbol with the next higher
904value. If the @code{bsd} output format is used the size of the symbol
905is printed, rather than the value, and @samp{-S} must be used in order
906both size and value to be printed.
907
908@item --special-syms
909Display symbols which have a target-specific special meaning. These
910symbols are usually used by the target for some special processing and
911are not normally helpful when included included in the normal symbol
912lists. For example for ARM targets this option would skip the mapping
913symbols used to mark transitions between ARM code, THUMB code and
914data.
915
916@item -t @var{radix}
917@itemx --radix=@var{radix}
918Use @var{radix} as the radix for printing the symbol values. It must be
919@samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
920
921@item --target=@var{bfdname}
922@cindex object code format
923Specify an object code format other than your system's default format.
924@xref{Target Selection}, for more information.
925
926@item -u
927@itemx --undefined-only
928@cindex external symbols
929@cindex undefined symbols
930Display only undefined symbols (those external to each object file).
931
932@item --defined-only
933@cindex external symbols
934@cindex undefined symbols
935Display only defined symbols for each object file.
936
937@item -V
938@itemx --version
939Show the version number of @command{nm} and exit.
940
941@item -X
942This option is ignored for compatibility with the AIX version of
943@command{nm}. It takes one parameter which must be the string
944@option{32_64}. The default mode of AIX @command{nm} corresponds
945to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
946
947@item --help
948Show a summary of the options to @command{nm} and exit.
949@end table
950
951@c man end
952
953@ignore
954@c man begin SEEALSO nm
955ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
956@c man end
957@end ignore
958
959@node objcopy
960@chapter objcopy
961
962@c man title objcopy copy and translate object files
963
964@smallexample
965@c man begin SYNOPSIS objcopy
966objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
967 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
968 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
969 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
970 [@option{-S}|@option{--strip-all}]
971 [@option{-g}|@option{--strip-debug}]
972 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
973 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
974 [@option{--strip-unneeded-symbol=}@var{symbolname}]
975 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
976 [@option{--localize-hidden}]
977 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
978 [@option{--globalize-symbol=}@var{symbolname}]
979 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
980 [@option{-w}|@option{--wildcard}]
981 [@option{-x}|@option{--discard-all}]
982 [@option{-X}|@option{--discard-locals}]
983 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
984 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
985 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
986 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
987 [@option{-p}|@option{--preserve-dates}]
988 [@option{--debugging}]
989 [@option{--gap-fill=}@var{val}]
990 [@option{--pad-to=}@var{address}]
991 [@option{--set-start=}@var{val}]
992 [@option{--adjust-start=}@var{incr}]
993 [@option{--change-addresses=}@var{incr}]
994 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
995 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
996 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
997 [@option{--change-warnings}] [@option{--no-change-warnings}]
998 [@option{--set-section-flags} @var{section}=@var{flags}]
999 [@option{--add-section} @var{sectionname}=@var{filename}]
1000 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
1001 [@option{--change-leading-char}] [@option{--remove-leading-char}]
1002 [@option{--reverse-bytes=}@var{num}]
1003 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
1004 [@option{--redefine-sym} @var{old}=@var{new}]
1005 [@option{--redefine-syms=}@var{filename}]
1006 [@option{--weaken}]
1007 [@option{--keep-symbols=}@var{filename}]
1008 [@option{--strip-symbols=}@var{filename}]
1009 [@option{--strip-unneeded-symbols=}@var{filename}]
1010 [@option{--keep-global-symbols=}@var{filename}]
1011 [@option{--localize-symbols=}@var{filename}]
1012 [@option{--globalize-symbols=}@var{filename}]
1013 [@option{--weaken-symbols=}@var{filename}]
1014 [@option{--alt-machine-code=}@var{index}]
1015 [@option{--prefix-symbols=}@var{string}]
1016 [@option{--prefix-sections=}@var{string}]
1017 [@option{--prefix-alloc-sections=}@var{string}]
1018 [@option{--add-gnu-debuglink=}@var{path-to-file}]
1019 [@option{--keep-file-symbols}]
1020 [@option{--only-keep-debug}]
1021 [@option{--extract-symbol}]
1022 [@option{--writable-text}]
1023 [@option{--readonly-text}]
1024 [@option{--pure}]
1025 [@option{--impure}]
1026 [@option{-v}|@option{--verbose}]
1027 [@option{-V}|@option{--version}]
1028 [@option{--help}] [@option{--info}]
1029 @var{infile} [@var{outfile}]
1030@c man end
1031@end smallexample
1032
1033@c man begin DESCRIPTION objcopy
1034The @sc{gnu} @command{objcopy} utility copies the contents of an object
1035file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
1036read and write the object files. It can write the destination object
1037file in a format different from that of the source object file. The
1038exact behavior of @command{objcopy} is controlled by command-line options.
1039Note that @command{objcopy} should be able to copy a fully linked file
1040between any two formats. However, copying a relocatable object file
1041between any two formats may not work as expected.
1042
1043@command{objcopy} creates temporary files to do its translations and
1044deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
1045translation work; it has access to all the formats described in @sc{bfd}
1046and thus is able to recognize most formats without being told
1047explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1048
1049@command{objcopy} can be used to generate S-records by using an output
1050target of @samp{srec} (e.g., use @samp{-O srec}).
1051
1052@command{objcopy} can be used to generate a raw binary file by using an
1053output target of @samp{binary} (e.g., use @option{-O binary}). When
1054@command{objcopy} generates a raw binary file, it will essentially produce
1055a memory dump of the contents of the input object file. All symbols and
1056relocation information will be discarded. The memory dump will start at
1057the load address of the lowest section copied into the output file.
1058
1059When generating an S-record or a raw binary file, it may be helpful to
1060use @option{-S} to remove sections containing debugging information. In
1061some cases @option{-R} will be useful to remove sections which contain
1062information that is not needed by the binary file.
1063
1064Note---@command{objcopy} is not able to change the endianness of its input
1065files. If the input format has an endianness (some formats do not),
1066@command{objcopy} can only copy the inputs into file formats that have the
1067same endianness or which have no endianness (e.g., @samp{srec}).
1068(However, see the @option{--reverse-bytes} option.)
1069
1070@c man end
1071
1072@c man begin OPTIONS objcopy
1073
1074@table @env
1075@item @var{infile}
1076@itemx @var{outfile}
1077The input and output files, respectively.
1078If you do not specify @var{outfile}, @command{objcopy} creates a
1079temporary file and destructively renames the result with
1080the name of @var{infile}.
1081
1082@item -I @var{bfdname}
1083@itemx --input-target=@var{bfdname}
1084Consider the source file's object format to be @var{bfdname}, rather than
1085attempting to deduce it. @xref{Target Selection}, for more information.
1086
1087@item -O @var{bfdname}
1088@itemx --output-target=@var{bfdname}
1089Write the output file using the object format @var{bfdname}.
1090@xref{Target Selection}, for more information.
1091
1092@item -F @var{bfdname}
1093@itemx --target=@var{bfdname}
1094Use @var{bfdname} as the object format for both the input and the output
1095file; i.e., simply transfer data from source to destination with no
1096translation. @xref{Target Selection}, for more information.
1097
1098@item -B @var{bfdarch}
1099@itemx --binary-architecture=@var{bfdarch}
1100Useful when transforming a raw binary input file into an object file.
1101In this case the output architecture can be set to @var{bfdarch}. This
1102option will be ignored if the input file has a known @var{bfdarch}. You
1103can access this binary data inside a program by referencing the special
1104symbols that are created by the conversion process. These symbols are
1105called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1106_binary_@var{objfile}_size. e.g. you can transform a picture file into
1107an object file and then access it in your code using these symbols.
1108
1109@item -j @var{sectionname}
1110@itemx --only-section=@var{sectionname}
1111Copy only the named section from the input file to the output file.
1112This option may be given more than once. Note that using this option
1113inappropriately may make the output file unusable.
1114
1115@item -R @var{sectionname}
1116@itemx --remove-section=@var{sectionname}
1117Remove any section named @var{sectionname} from the output file. This
1118option may be given more than once. Note that using this option
1119inappropriately may make the output file unusable.
1120
1121@item -S
1122@itemx --strip-all
1123Do not copy relocation and symbol information from the source file.
1124
1125@item -g
1126@itemx --strip-debug
1127Do not copy debugging symbols or sections from the source file.
1128
1129@item --strip-unneeded
1130Strip all symbols that are not needed for relocation processing.
1131
1132@item -K @var{symbolname}
1133@itemx --keep-symbol=@var{symbolname}
1134When stripping symbols, keep symbol @var{symbolname} even if it would
1135normally be stripped. This option may be given more than once.
1136
1137@item -N @var{symbolname}
1138@itemx --strip-symbol=@var{symbolname}
1139Do not copy symbol @var{symbolname} from the source file. This option
1140may be given more than once.
1141
1142@item --strip-unneeded-symbol=@var{symbolname}
1143Do not copy symbol @var{symbolname} from the source file unless it is needed
1144by a relocation. This option may be given more than once.
1145
1146@item -G @var{symbolname}
1147@itemx --keep-global-symbol=@var{symbolname}
1148Keep only symbol @var{symbolname} global. Make all other symbols local
1149to the file, so that they are not visible externally. This option may
1150be given more than once.
1151
1152@item --localize-hidden
1153In an ELF object, mark all symbols that have hidden or internal visibility
1154as local. This option applies on top of symbol-specific localization options
1155such as @option{-L}.
1156
1157@item -L @var{symbolname}
1158@itemx --localize-symbol=@var{symbolname}
1159Make symbol @var{symbolname} local to the file, so that it is not
1160visible externally. This option may be given more than once.
1161
1162@item -W @var{symbolname}
1163@itemx --weaken-symbol=@var{symbolname}
1164Make symbol @var{symbolname} weak. This option may be given more than once.
1165
1166@item --globalize-symbol=@var{symbolname}
1167Give symbol @var{symbolname} global scoping so that it is visible
1168outside of the file in which it is defined. This option may be given
1169more than once.
1170
1171@item -w
1172@itemx --wildcard
1173Permit regular expressions in @var{symbolname}s used in other command
1174line options. The question mark (?), asterisk (*), backslash (\) and
1175square brackets ([]) operators can be used anywhere in the symbol
1176name. If the first character of the symbol name is the exclamation
1177point (!) then the sense of the switch is reversed for that symbol.
1178For example:
1179
1180@smallexample
1181 -w -W !foo -W fo*
1182@end smallexample
1183
1184would cause objcopy to weaken all symbols that start with ``fo''
1185except for the symbol ``foo''.
1186
1187@item -x
1188@itemx --discard-all
1189Do not copy non-global symbols from the source file.
1190@c FIXME any reason to prefer "non-global" to "local" here?
1191
1192@item -X
1193@itemx --discard-locals
1194Do not copy compiler-generated local symbols.
1195(These usually start with @samp{L} or @samp{.}.)
1196
1197@item -b @var{byte}
1198@itemx --byte=@var{byte}
1199Keep only every @var{byte}th byte of the input file (header data is not
1200affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1201where @var{interleave} is given by the @option{-i} or @option{--interleave}
1202option, or the default of 4. This option is useful for creating files
1203to program @sc{rom}. It is typically used with an @code{srec} output
1204target.
1205
1206@item -i @var{interleave}
1207@itemx --interleave=@var{interleave}
1208Only copy one out of every @var{interleave} bytes. Select which byte to
1209copy with the @option{-b} or @option{--byte} option. The default is 4.
1210@command{objcopy} ignores this option if you do not specify either @option{-b} or
1211@option{--byte}.
1212
1213@item -p
1214@itemx --preserve-dates
1215Set the access and modification dates of the output file to be the same
1216as those of the input file.
1217
1218@item --debugging
1219Convert debugging information, if possible. This is not the default
1220because only certain debugging formats are supported, and the
1221conversion process can be time consuming.
1222
1223@item --gap-fill @var{val}
1224Fill gaps between sections with @var{val}. This operation applies to
1225the @emph{load address} (LMA) of the sections. It is done by increasing
1226the size of the section with the lower address, and filling in the extra
1227space created with @var{val}.
1228
1229@item --pad-to @var{address}
1230Pad the output file up to the load address @var{address}. This is
1231done by increasing the size of the last section. The extra space is
1232filled in with the value specified by @option{--gap-fill} (default zero).
1233
1234@item --set-start @var{val}
1235Set the start address of the new file to @var{val}. Not all object file
1236formats support setting the start address.
1237
1238@item --change-start @var{incr}
1239@itemx --adjust-start @var{incr}
1240@cindex changing start address
1241Change the start address by adding @var{incr}. Not all object file
1242formats support setting the start address.
1243
1244@item --change-addresses @var{incr}
1245@itemx --adjust-vma @var{incr}
1246@cindex changing object addresses
1247Change the VMA and LMA addresses of all sections, as well as the start
1248address, by adding @var{incr}. Some object file formats do not permit
1249section addresses to be changed arbitrarily. Note that this does not
1250relocate the sections; if the program expects sections to be loaded at a
1251certain address, and this option is used to change the sections such
1252that they are loaded at a different address, the program may fail.
1253
1254@item --change-section-address @var{section}@{=,+,-@}@var{val}
1255@itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1256@cindex changing section address
1257Set or change both the VMA address and the LMA address of the named
1258@var{section}. If @samp{=} is used, the section address is set to
1259@var{val}. Otherwise, @var{val} is added to or subtracted from the
1260section address. See the comments under @option{--change-addresses},
1261above. If @var{section} does not exist in the input file, a warning will
1262be issued, unless @option{--no-change-warnings} is used.
1263
1264@item --change-section-lma @var{section}@{=,+,-@}@var{val}
1265@cindex changing section LMA
1266Set or change the LMA address of the named @var{section}. The LMA
1267address is the address where the section will be loaded into memory at
1268program load time. Normally this is the same as the VMA address, which
1269is the address of the section at program run time, but on some systems,
1270especially those where a program is held in ROM, the two can be
1271different. If @samp{=} is used, the section address is set to
1272@var{val}. Otherwise, @var{val} is added to or subtracted from the
1273section address. See the comments under @option{--change-addresses},
1274above. If @var{section} does not exist in the input file, a warning
1275will be issued, unless @option{--no-change-warnings} is used.
1276
1277@item --change-section-vma @var{section}@{=,+,-@}@var{val}
1278@cindex changing section VMA
1279Set or change the VMA address of the named @var{section}. The VMA
1280address is the address where the section will be located once the
1281program has started executing. Normally this is the same as the LMA
1282address, which is the address where the section will be loaded into
1283memory, but on some systems, especially those where a program is held in
1284ROM, the two can be different. If @samp{=} is used, the section address
1285is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1286from the section address. See the comments under
1287@option{--change-addresses}, above. If @var{section} does not exist in
1288the input file, a warning will be issued, unless
1289@option{--no-change-warnings} is used.
1290
1291@item --change-warnings
1292@itemx --adjust-warnings
1293If @option{--change-section-address} or @option{--change-section-lma} or
1294@option{--change-section-vma} is used, and the named section does not
1295exist, issue a warning. This is the default.
1296
1297@item --no-change-warnings
1298@itemx --no-adjust-warnings
1299Do not issue a warning if @option{--change-section-address} or
1300@option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1301if the named section does not exist.
1302
1303@item --set-section-flags @var{section}=@var{flags}
1304Set the flags for the named section. The @var{flags} argument is a
1305comma separated string of flag names. The recognized names are
1306@samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1307@samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1308@samp{debug}. You can set the @samp{contents} flag for a section which
1309does not have contents, but it is not meaningful to clear the
1310@samp{contents} flag of a section which does have contents--just remove
1311the section instead. Not all flags are meaningful for all object file
1312formats.
1313
1314@item --add-section @var{sectionname}=@var{filename}
1315Add a new section named @var{sectionname} while copying the file. The
1316contents of the new section are taken from the file @var{filename}. The
1317size of the section will be the size of the file. This option only
1318works on file formats which can support sections with arbitrary names.
1319
1320@item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1321Rename a section from @var{oldname} to @var{newname}, optionally
1322changing the section's flags to @var{flags} in the process. This has
1323the advantage over usng a linker script to perform the rename in that
1324the output stays as an object file and does not become a linked
1325executable.
1326
1327This option is particularly helpful when the input format is binary,
1328since this will always create a section called .data. If for example,
1329you wanted instead to create a section called .rodata containing binary
1330data you could use the following command line to achieve it:
1331
1332@smallexample
1333 objcopy -I binary -O <output_format> -B <architecture> \
1334 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1335 <input_binary_file> <output_object_file>
1336@end smallexample
1337
1338@item --change-leading-char
1339Some object file formats use special characters at the start of
1340symbols. The most common such character is underscore, which compilers
1341often add before every symbol. This option tells @command{objcopy} to
1342change the leading character of every symbol when it converts between
1343object file formats. If the object file formats use the same leading
1344character, this option has no effect. Otherwise, it will add a
1345character, or remove a character, or change a character, as
1346appropriate.
1347
1348@item --remove-leading-char
1349If the first character of a global symbol is a special symbol leading
1350character used by the object file format, remove the character. The
1351most common symbol leading character is underscore. This option will
1352remove a leading underscore from all global symbols. This can be useful
1353if you want to link together objects of different file formats with
1354different conventions for symbol names. This is different from
1355@option{--change-leading-char} because it always changes the symbol name
1356when appropriate, regardless of the object file format of the output
1357file.
1358
1359@item --reverse-bytes=@var{num}
1360Reverse the bytes in a section with output contents. A section length must
1361be evenly divisible by the value given in order for the swap to be able to
1362take place. Reversing takes place before the interleaving is performed.
1363
1364This option is used typically in generating ROM images for problematic
1365target systems. For example, on some target boards, the 32-bit words
1366fetched from 8-bit ROMs are re-assembled in little-endian byte order
1367regardless of the CPU byte order. Depending on the programming model, the
1368endianness of the ROM may need to be modified.
1369
1370Consider a simple file with a section containing the following eight
1371bytes: @code{12345678}.
1372
1373Using @samp{--reverse-bytes=2} for the above example, the bytes in the
1374output file would be ordered @code{21436587}.
1375
1376Using @samp{--reverse-bytes=4} for the above example, the bytes in the
1377output file would be ordered @code{43218765}.
1378
1379By using @samp{--reverse-bytes=2} for the above example, followed by
1380@samp{--reverse-bytes=4} on the output file, the bytes in the second
1381output file would be ordered @code{34127856}.
1382
1383@item --srec-len=@var{ival}
1384Meaningful only for srec output. Set the maximum length of the Srecords
1385being produced to @var{ival}. This length covers both address, data and
1386crc fields.
1387
1388@item --srec-forceS3
1389Meaningful only for srec output. Avoid generation of S1/S2 records,
1390creating S3-only record format.
1391
1392@item --redefine-sym @var{old}=@var{new}
1393Change the name of a symbol @var{old}, to @var{new}. This can be useful
1394when one is trying link two things together for which you have no
1395source, and there are name collisions.
1396
1397@item --redefine-syms=@var{filename}
1398Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1399listed in the file @var{filename}. @var{filename} is simply a flat file,
1400with one symbol pair per line. Line comments may be introduced by the hash
1401character. This option may be given more than once.
1402
1403@item --weaken
1404Change all global symbols in the file to be weak. This can be useful
1405when building an object which will be linked against other objects using
1406the @option{-R} option to the linker. This option is only effective when
1407using an object file format which supports weak symbols.
1408
1409@item --keep-symbols=@var{filename}
1410Apply @option{--keep-symbol} option to each symbol listed in the file
1411@var{filename}. @var{filename} is simply a flat file, with one symbol
1412name per line. Line comments may be introduced by the hash character.
1413This option may be given more than once.
1414
1415@item --strip-symbols=@var{filename}
1416Apply @option{--strip-symbol} option to each symbol listed in the file
1417@var{filename}. @var{filename} is simply a flat file, with one symbol
1418name per line. Line comments may be introduced by the hash character.
1419This option may be given more than once.
1420
1421@item --strip-unneeded-symbols=@var{filename}
1422Apply @option{--strip-unneeded-symbol} option to each symbol listed in
1423the file @var{filename}. @var{filename} is simply a flat file, with one
1424symbol name per line. Line comments may be introduced by the hash
1425character. This option may be given more than once.
1426
1427@item --keep-global-symbols=@var{filename}
1428Apply @option{--keep-global-symbol} option to each symbol listed in the
1429file @var{filename}. @var{filename} is simply a flat file, with one
1430symbol name per line. Line comments may be introduced by the hash
1431character. This option may be given more than once.
1432
1433@item --localize-symbols=@var{filename}
1434Apply @option{--localize-symbol} option to each symbol listed in the file
1435@var{filename}. @var{filename} is simply a flat file, with one symbol
1436name per line. Line comments may be introduced by the hash character.
1437This option may be given more than once.
1438
1439@item --globalize-symbols=@var{filename}
1440Apply @option{--globalize-symbol} option to each symbol listed in the file
1441@var{filename}. @var{filename} is simply a flat file, with one symbol
1442name per line. Line comments may be introduced by the hash character.
1443This option may be given more than once.
1444
1445@item --weaken-symbols=@var{filename}
1446Apply @option{--weaken-symbol} option to each symbol listed in the file
1447@var{filename}. @var{filename} is simply a flat file, with one symbol
1448name per line. Line comments may be introduced by the hash character.
1449This option may be given more than once.
1450
1451@item --alt-machine-code=@var{index}
1452If the output architecture has alternate machine codes, use the
1453@var{index}th code instead of the default one. This is useful in case
1454a machine is assigned an official code and the tool-chain adopts the
1455new code, but other applications still depend on the original code
1456being used. For ELF based architectures if the @var{index}
1457alternative does not exist then the value is treated as an absolute
1458number to be stored in the e_machine field of the ELF header.
1459
1460@item --writable-text
1461Mark the output text as writable. This option isn't meaningful for all
1462object file formats.
1463
1464@item --readonly-text
1465Make the output text write protected. This option isn't meaningful for all
1466object file formats.
1467
1468@item --pure
1469Mark the output file as demand paged. This option isn't meaningful for all
1470object file formats.
1471
1472@item --impure
1473Mark the output file as impure. This option isn't meaningful for all
1474object file formats.
1475
1476@item --prefix-symbols=@var{string}
1477Prefix all symbols in the output file with @var{string}.
1478
1479@item --prefix-sections=@var{string}
1480Prefix all section names in the output file with @var{string}.
1481
1482@item --prefix-alloc-sections=@var{string}
1483Prefix all the names of all allocated sections in the output file with
1484@var{string}.
1485
1486@item --add-gnu-debuglink=@var{path-to-file}
1487Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1488and adds it to the output file.
1489
1490@item --keep-file-symbols
1491When stripping a file, perhaps with @option{--strip-debug} or
1492@option{--strip-unneeded}, retain any symbols specifying source file names,
1493which would otherwise get stripped.
1494
1495@item --only-keep-debug
1496Strip a file, removing contents of any sections that would not be
1497stripped by @option{--strip-debug} and leaving the debugging sections
1498intact. In ELF files, this preserves all note sections in the output.
1499
1500The intention is that this option will be used in conjunction with
1501@option{--add-gnu-debuglink} to create a two part executable. One a
1502stripped binary which will occupy less space in RAM and in a
1503distribution and the second a debugging information file which is only
1504needed if debugging abilities are required. The suggested procedure
1505to create these files is as follows:
1506
1507@enumerate
1508@item Link the executable as normal. Assuming that is is called
1509@code{foo} then...
1510@item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1511create a file containing the debugging info.
1512@item Run @code{objcopy --strip-debug foo} to create a
1513stripped executable.
1514@item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1515to add a link to the debugging info into the stripped executable.
1516@end enumerate
1517
1518Note---the choice of @code{.dbg} as an extension for the debug info
1519file is arbitrary. Also the @code{--only-keep-debug} step is
1520optional. You could instead do this:
1521
1522@enumerate
1523@item Link the executable as normal.
1524@item Copy @code{foo} to @code{foo.full}
1525@item Run @code{objcopy --strip-debug foo}
1526@item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1527@end enumerate
1528
1529i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
1530full executable. It does not have to be a file created by the
1531@option{--only-keep-debug} switch.
1532
1533Note---this switch is only intended for use on fully linked files. It
1534does not make sense to use it on object files where the debugging
1535information may be incomplete. Besides the gnu_debuglink feature
1536currently only supports the presence of one filename containing
1537debugging information, not multiple filenames on a one-per-object-file
1538basis.
1539
1540@item --extract-symbol
1541Keep the file's section flags and symbols but remove all section data.
1542Specifically, the option:
1543
1544@itemize
1545@item sets the virtual and load addresses of every section to zero;
1546@item removes the contents of all sections;
1547@item sets the size of every section to zero; and
1548@item sets the file's start address to zero.
1549@end itemize
1550
1551This option is used to build a @file{.sym} file for a VxWorks kernel.
1552It can also be a useful way of reducing the size of a @option{--just-symbols}
1553linker input file.
1554
1555@item -V
1556@itemx --version
1557Show the version number of @command{objcopy}.
1558
1559@item -v
1560@itemx --verbose
1561Verbose output: list all object files modified. In the case of
1562archives, @samp{objcopy -V} lists all members of the archive.
1563
1564@item --help
1565Show a summary of the options to @command{objcopy}.
1566
1567@item --info
1568Display a list showing all architectures and object formats available.
1569@end table
1570
1571@c man end
1572
1573@ignore
1574@c man begin SEEALSO objcopy
1575ld(1), objdump(1), and the Info entries for @file{binutils}.
1576@c man end
1577@end ignore
1578
1579@node objdump
1580@chapter objdump
1581
1582@cindex object file information
1583@kindex objdump
1584
1585@c man title objdump display information from object files.
1586
1587@smallexample
1588@c man begin SYNOPSIS objdump
1589objdump [@option{-a}|@option{--archive-headers}]
1590 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1591 [@option{-C}|@option{--demangle}[=@var{style}] ]
1592 [@option{-d}|@option{--disassemble}]
1593 [@option{-D}|@option{--disassemble-all}]
1594 [@option{-z}|@option{--disassemble-zeroes}]
1595 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1596 [@option{-f}|@option{--file-headers}]
1597 [@option{--file-start-context}]
1598 [@option{-g}|@option{--debugging}]
1599 [@option{-e}|@option{--debugging-tags}]
1600 [@option{-h}|@option{--section-headers}|@option{--headers}]
1601 [@option{-i}|@option{--info}]
1602 [@option{-j} @var{section}|@option{--section=}@var{section}]
1603 [@option{-l}|@option{--line-numbers}]
1604 [@option{-S}|@option{--source}]
1605 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1606 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1607 [@option{-p}|@option{--private-headers}]
1608 [@option{-r}|@option{--reloc}]
1609 [@option{-R}|@option{--dynamic-reloc}]
1610 [@option{-s}|@option{--full-contents}]
1611 [@option{-W}|@option{--dwarf}]
1612 [@option{-G}|@option{--stabs}]
1613 [@option{-t}|@option{--syms}]
1614 [@option{-T}|@option{--dynamic-syms}]
1615 [@option{-x}|@option{--all-headers}]
1616 [@option{-w}|@option{--wide}]
1617 [@option{--start-address=}@var{address}]
1618 [@option{--stop-address=}@var{address}]
1619 [@option{--prefix-addresses}]
1620 [@option{--[no-]show-raw-insn}]
1621 [@option{--adjust-vma=}@var{offset}]
1622 [@option{--special-syms}]
1623 [@option{-V}|@option{--version}]
1624 [@option{-H}|@option{--help}]
1625 @var{objfile}@dots{}
1626@c man end
1627@end smallexample
1628
1629@c man begin DESCRIPTION objdump
1630
1631@command{objdump} displays information about one or more object files.
1632The options control what particular information to display. This
1633information is mostly useful to programmers who are working on the
1634compilation tools, as opposed to programmers who just want their
1635program to compile and work.
1636
1637@var{objfile}@dots{} are the object files to be examined. When you
1638specify archives, @command{objdump} shows information on each of the member
1639object files.
1640
1641@c man end
1642
1643@c man begin OPTIONS objdump
1644
1645The long and short forms of options, shown here as alternatives, are
1646equivalent. At least one option from the list
1647@option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1648
1649@table @env
1650@item -a
1651@itemx --archive-header
1652@cindex archive headers
1653If any of the @var{objfile} files are archives, display the archive
1654header information (in a format similar to @samp{ls -l}). Besides the
1655information you could list with @samp{ar tv}, @samp{objdump -a} shows
1656the object file format of each archive member.
1657
1658@item --adjust-vma=@var{offset}
1659@cindex section addresses in objdump
1660@cindex VMA in objdump
1661When dumping information, first add @var{offset} to all the section
1662addresses. This is useful if the section addresses do not correspond to
1663the symbol table, which can happen when putting sections at particular
1664addresses when using a format which can not represent section addresses,
1665such as a.out.
1666
1667@item -b @var{bfdname}
1668@itemx --target=@var{bfdname}
1669@cindex object code format
1670Specify that the object-code format for the object files is
1671@var{bfdname}. This option may not be necessary; @var{objdump} can
1672automatically recognize many formats.
1673
1674For example,
1675@example
1676objdump -b oasys -m vax -h fu.o
1677@end example
1678@noindent
1679displays summary information from the section headers (@option{-h}) of
1680@file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1681file in the format produced by Oasys compilers. You can list the
1682formats available with the @option{-i} option.
1683@xref{Target Selection}, for more information.
1684
1685@item -C
1686@itemx --demangle[=@var{style}]
1687@cindex demangling in objdump
1688Decode (@dfn{demangle}) low-level symbol names into user-level names.
1689Besides removing any initial underscore prepended by the system, this
1690makes C++ function names readable. Different compilers have different
1691mangling styles. The optional demangling style argument can be used to
1692choose an appropriate demangling style for your compiler. @xref{c++filt},
1693for more information on demangling.
1694
1695@item -g
1696@itemx --debugging
1697Display debugging information. This attempts to parse debugging
1698information stored in the file and print it out using a C like syntax.
1699Only certain types of debugging information have been implemented.
1700Some other types are supported by @command{readelf -w}.
1701@xref{readelf}.
1702
1703@item -e
1704@itemx --debugging-tags
1705Like @option{-g}, but the information is generated in a format compatible
1706with ctags tool.
1707
1708@item -d
1709@itemx --disassemble
1710@cindex disassembling object code
1711@cindex machine instructions
1712Display the assembler mnemonics for the machine instructions from
1713@var{objfile}. This option only disassembles those sections which are
1714expected to contain instructions.
1715
1716@item -D
1717@itemx --disassemble-all
1718Like @option{-d}, but disassemble the contents of all sections, not just
1719those expected to contain instructions.
1720
1721@item --prefix-addresses
1722When disassembling, print the complete address on each line. This is
1723the older disassembly format.
1724
1725@item -EB
1726@itemx -EL
1727@itemx --endian=@{big|little@}
1728@cindex endianness
1729@cindex disassembly endianness
1730Specify the endianness of the object files. This only affects
1731disassembly. This can be useful when disassembling a file format which
1732does not describe endianness information, such as S-records.
1733
1734@item -f
1735@itemx --file-headers
1736@cindex object file header
1737Display summary information from the overall header of
1738each of the @var{objfile} files.
1739
1740@item --file-start-context
1741@cindex source code context
1742Specify that when displaying interlisted source code/disassembly
1743(assumes @option{-S}) from a file that has not yet been displayed, extend the
1744context to the start of the file.
1745
1746@item -h
1747@itemx --section-headers
1748@itemx --headers
1749@cindex section headers
1750Display summary information from the section headers of the
1751object file.
1752
1753File segments may be relocated to nonstandard addresses, for example by
1754using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1755@command{ld}. However, some object file formats, such as a.out, do not
1756store the starting address of the file segments. In those situations,
1757although @command{ld} relocates the sections correctly, using @samp{objdump
1758-h} to list the file section headers cannot show the correct addresses.
1759Instead, it shows the usual addresses, which are implicit for the
1760target.
1761
1762@item -H
1763@itemx --help
1764Print a summary of the options to @command{objdump} and exit.
1765
1766@item -i
1767@itemx --info
1768@cindex architectures available
1769@cindex object formats available
1770Display a list showing all architectures and object formats available
1771for specification with @option{-b} or @option{-m}.
1772
1773@item -j @var{name}
1774@itemx --section=@var{name}
1775@cindex section information
1776Display information only for section @var{name}.
1777
1778@item -l
1779@itemx --line-numbers
1780@cindex source filenames for object files
1781Label the display (using debugging information) with the filename and
1782source line numbers corresponding to the object code or relocs shown.
1783Only useful with @option{-d}, @option{-D}, or @option{-r}.
1784
1785@item -m @var{machine}
1786@itemx --architecture=@var{machine}
1787@cindex architecture
1788@cindex disassembly architecture
1789Specify the architecture to use when disassembling object files. This
1790can be useful when disassembling object files which do not describe
1791architecture information, such as S-records. You can list the available
1792architectures with the @option{-i} option.
1793
1794@item -M @var{options}
1795@itemx --disassembler-options=@var{options}
1796Pass target specific information to the disassembler. Only supported on
1797some targets. If it is necessary to specify more than one
1798disassembler option then multiple @option{-M} options can be used or
1799can be placed together into a comma separated list.
1800
1801If the target is an ARM architecture then this switch can be used to
1802select which register name set is used during disassembler. Specifying
1803@option{-M reg-names-std} (the default) will select the register names as
1804used in ARM's instruction set documentation, but with register 13 called
1805'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1806@option{-M reg-names-apcs} will select the name set used by the ARM
1807Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1808just use @samp{r} followed by the register number.
1809
1810There are also two variants on the APCS register naming scheme enabled
1811by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1812use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1813with the normal register names or the special register names).
1814
1815This option can also be used for ARM architectures to force the
1816disassembler to interpret all instructions as Thumb instructions by
1817using the switch @option{--disassembler-options=force-thumb}. This can be
1818useful when attempting to disassemble thumb code produced by other
1819compilers.
1820
1821For the x86, some of the options duplicate functions of the @option{-m}
1822switch, but allow finer grained control. Multiple selections from the
1823following may be specified as a comma separated string.
1824@option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1825the given architecture. @option{intel} and @option{att} select between
1826intel syntax mode and AT&T syntax mode. @option{addr64}, @option{addr32},
1827@option{addr16}, @option{data32} and @option{data16} specify the default
1828address size and operand size. These four options will be overridden if
1829@option{x86-64}, @option{i386} or @option{i8086} appear later in the
1830option string. Lastly, @option{suffix}, when in AT&T mode,
1831instructs the disassembler to print a mnemonic suffix even when the
1832suffix could be inferred by the operands.
1833
1834For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1835disassembly of BookE instructions. @option{32} and @option{64} select
1836PowerPC and PowerPC64 disassembly, respectively. @option{e300}
1837selects disassembly for the e300 family. @option{440} selects
1838disassembly for the PowerPC 440. @option{ppcps} selects disassembly
1839for the paired single instructions of the PPC750CL.
1840
1841For MIPS, this option controls the printing of instruction mnemonic
1842names and register names in disassembled instructions. Multiple
1843selections from the following may be specified as a comma separated
1844string, and invalid options are ignored:
1845
1846@table @code
1847@item no-aliases
1848Print the 'raw' instruction mnemonic instead of some pseudo
1849instruction mnemonic. I.e., print 'daddu' or 'or' instead of 'move',
1850'sll' instead of 'nop', etc.
1851
1852@item gpr-names=@var{ABI}
1853Print GPR (general-purpose register) names as appropriate
1854for the specified ABI. By default, GPR names are selected according to
1855the ABI of the binary being disassembled.
1856
1857@item fpr-names=@var{ABI}
1858Print FPR (floating-point register) names as
1859appropriate for the specified ABI. By default, FPR numbers are printed
1860rather than names.
1861
1862@item cp0-names=@var{ARCH}
1863Print CP0 (system control coprocessor; coprocessor 0) register names
1864as appropriate for the CPU or architecture specified by
1865@var{ARCH}. By default, CP0 register names are selected according to
1866the architecture and CPU of the binary being disassembled.
1867
1868@item hwr-names=@var{ARCH}
1869Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1870as appropriate for the CPU or architecture specified by
1871@var{ARCH}. By default, HWR names are selected according to
1872the architecture and CPU of the binary being disassembled.
1873
1874@item reg-names=@var{ABI}
1875Print GPR and FPR names as appropriate for the selected ABI.
1876
1877@item reg-names=@var{ARCH}
1878Print CPU-specific register names (CP0 register and HWR names)
1879as appropriate for the selected CPU or architecture.
1880@end table
1881
1882For any of the options listed above, @var{ABI} or
1883@var{ARCH} may be specified as @samp{numeric} to have numbers printed
1884rather than names, for the selected types of registers.
1885You can list the available values of @var{ABI} and @var{ARCH} using
1886the @option{--help} option.
1887
1888For VAX, you can specify function entry addresses with @option{-M
1889entry:0xf00ba}. You can use this multiple times to properly
1890disassemble VAX binary files that don't contain symbol tables (like
1891ROM dumps). In these cases, the function entry mask would otherwise
1892be decoded as VAX instructions, which would probably lead the rest
1893of the function being wrongly disassembled.
1894
1895@item -p
1896@itemx --private-headers
1897Print information that is specific to the object file format. The exact
1898information printed depends upon the object file format. For some
1899object file formats, no additional information is printed.
1900
1901@item -r
1902@itemx --reloc
1903@cindex relocation entries, in object file
1904Print the relocation entries of the file. If used with @option{-d} or
1905@option{-D}, the relocations are printed interspersed with the
1906disassembly.
1907
1908@item -R
1909@itemx --dynamic-reloc
1910@cindex dynamic relocation entries, in object file
1911Print the dynamic relocation entries of the file. This is only
1912meaningful for dynamic objects, such as certain types of shared
1913libraries.
1914
1915@item -s
1916@itemx --full-contents
1917@cindex sections, full contents
1918@cindex object file sections
1919Display the full contents of any sections requested. By default all
1920non-empty sections are displayed.
1921
1922@item -S
1923@itemx --source
1924@cindex source disassembly
1925@cindex disassembly, with source
1926Display source code intermixed with disassembly, if possible. Implies
1927@option{-d}.
1928
1929@item --show-raw-insn
1930When disassembling instructions, print the instruction in hex as well as
1931in symbolic form. This is the default except when
1932@option{--prefix-addresses} is used.
1933
1934@item --no-show-raw-insn
1935When disassembling instructions, do not print the instruction bytes.
1936This is the default when @option{--prefix-addresses} is used.
1937
1938@item -W
1939@itemx --dwarf
1940@cindex DWARF
1941@cindex debug symbols
1942Displays the contents of the DWARF debug sections in the file, if any
1943are present.
1944
1945@item -G
1946@itemx --stabs
1947@cindex stab
1948@cindex .stab
1949@cindex debug symbols
1950@cindex ELF object file format
1951Display the full contents of any sections requested. Display the
1952contents of the .stab and .stab.index and .stab.excl sections from an
1953ELF file. This is only useful on systems (such as Solaris 2.0) in which
1954@code{.stab} debugging symbol-table entries are carried in an ELF
1955section. In most other file formats, debugging symbol-table entries are
1956interleaved with linkage symbols, and are visible in the @option{--syms}
1957output.
1958@ifclear man
1959For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1960Overview,stabs.info, The ``stabs'' debug format}.
1961@end ifclear
1962
1963@item --start-address=@var{address}
1964@cindex start-address
1965Start displaying data at the specified address. This affects the output
1966of the @option{-d}, @option{-r} and @option{-s} options.
1967
1968@item --stop-address=@var{address}
1969@cindex stop-address
1970Stop displaying data at the specified address. This affects the output
1971of the @option{-d}, @option{-r} and @option{-s} options.
1972
1973@item -t
1974@itemx --syms
1975@cindex symbol table entries, printing
1976Print the symbol table entries of the file.
1977This is similar to the information provided by the @samp{nm} program,
1978although the display format is different. The format of the output
1979depends upon the format of the file being dumped, but there are two main
1980types. One looks like this:
1981
1982@smallexample
1983[ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
1984[ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
1985@end smallexample
1986
1987where the number inside the square brackets is the number of the entry
1988in the symbol table, the @var{sec} number is the section number, the
1989@var{fl} value are the symbol's flag bits, the @var{ty} number is the
1990symbol's type, the @var{scl} number is the symbol's storage class and
1991the @var{nx} value is the number of auxilary entries associated with
1992the symbol. The last two fields are the symbol's value and its name.
1993
1994The other common output format, usually seen with ELF based files,
1995looks like this:
1996
1997@smallexample
199800000000 l d .bss 00000000 .bss
199900000000 g .text 00000000 fred
2000@end smallexample
2001
2002Here the first number is the symbol's value (sometimes refered to as
2003its address). The next field is actually a set of characters and
2004spaces indicating the flag bits that are set on the symbol. These
2005characters are described below. Next is the section with which the
2006symbol is associated or @emph{*ABS*} if the section is absolute (ie
2007not connected with any section), or @emph{*UND*} if the section is
2008referenced in the file being dumped, but not defined there.
2009
2010After the section name comes another field, a number, which for common
2011symbols is the alignment and for other symbol is the size. Finally
2012the symbol's name is displayed.
2013
2014The flag characters are divided into 7 groups as follows:
2015@table @code
2016@item l
2017@itemx g
2018@itemx !
2019The symbol is local (l), global (g), neither (a space) or both (!). A
2020symbol can be neither local or global for a variety of reasons, e.g.,
2021because it is used for debugging, but it is probably an indication of
2022a bug if it is ever both local and global.
2023
2024@item w
2025The symbol is weak (w) or strong (a space).
2026
2027@item C
2028The symbol denotes a constructor (C) or an ordinary symbol (a space).
2029
2030@item W
2031The symbol is a warning (W) or a normal symbol (a space). A warning
2032symbol's name is a message to be displayed if the symbol following the
2033warning symbol is ever referenced.
2034
2035@item I
2036The symbol is an indirect reference to another symbol (I) or a normal
2037symbol (a space).
2038
2039@item d
2040@itemx D
2041The symbol is a debugging symbol (d) or a dynamic symbol (D) or a
2042normal symbol (a space).
2043
2044@item F
2045@item f
2046@item O
2047The symbol is the name of a function (F) or a file (f) or an object
2048(O) or just a normal symbol (a space).
2049@end table
2050
2051@item -T
2052@itemx --dynamic-syms
2053@cindex dynamic symbol table entries, printing
2054Print the dynamic symbol table entries of the file. This is only
2055meaningful for dynamic objects, such as certain types of shared
2056libraries. This is similar to the information provided by the @samp{nm}
2057program when given the @option{-D} (@option{--dynamic}) option.
2058
2059@item --special-syms
2060When displaying symbols include those which the target considers to be
2061special in some way and which would not normally be of interest to the
2062user.
2063
2064@item -V
2065@itemx --version
2066Print the version number of @command{objdump} and exit.
2067
2068@item -x
2069@itemx --all-headers
2070@cindex all header information, object file
2071@cindex header information, all
2072Display all available header information, including the symbol table and
2073relocation entries. Using @option{-x} is equivalent to specifying all of
2074@option{-a -f -h -p -r -t}.
2075
2076@item -w
2077@itemx --wide
2078@cindex wide output, printing
2079Format some lines for output devices that have more than 80 columns.
2080Also do not truncate symbol names when they are displayed.
2081
2082@item -z
2083@itemx --disassemble-zeroes
2084Normally the disassembly output will skip blocks of zeroes. This
2085option directs the disassembler to disassemble those blocks, just like
2086any other data.
2087@end table
2088
2089@c man end
2090
2091@ignore
2092@c man begin SEEALSO objdump
2093nm(1), readelf(1), and the Info entries for @file{binutils}.
2094@c man end
2095@end ignore
2096
2097@node ranlib
2098@chapter ranlib
2099
2100@kindex ranlib
2101@cindex archive contents
2102@cindex symbol index
2103
2104@c man title ranlib generate index to archive.
2105
2106@smallexample
2107@c man begin SYNOPSIS ranlib
2108ranlib [@option{-vV}] @var{archive}
2109@c man end
2110@end smallexample
2111
2112@c man begin DESCRIPTION ranlib
2113
2114@command{ranlib} generates an index to the contents of an archive and
2115stores it in the archive. The index lists each symbol defined by a
2116member of an archive that is a relocatable object file.
2117
2118You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
2119
2120An archive with such an index speeds up linking to the library and
2121allows routines in the library to call each other without regard to
2122their placement in the archive.
2123
2124The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
2125@command{ranlib} is completely equivalent to executing @samp{ar -s}.
2126@xref{ar}.
2127
2128@c man end
2129
2130@c man begin OPTIONS ranlib
2131
2132@table @env
2133@item -v
2134@itemx -V
2135@itemx --version
2136Show the version number of @command{ranlib}.
2137@end table
2138
2139@c man end
2140
2141@ignore
2142@c man begin SEEALSO ranlib
2143ar(1), nm(1), and the Info entries for @file{binutils}.
2144@c man end
2145@end ignore
2146
2147@node size
2148@chapter size
2149
2150@kindex size
2151@cindex section sizes
2152
2153@c man title size list section sizes and total size.
2154
2155@smallexample
2156@c man begin SYNOPSIS size
2157size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
2158 [@option{--help}]
2159 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
2160 [@option{--common}]
2161 [@option{-t}|@option{--totals}]
2162 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
2163 [@var{objfile}@dots{}]
2164@c man end
2165@end smallexample
2166
2167@c man begin DESCRIPTION size
2168
2169The @sc{gnu} @command{size} utility lists the section sizes---and the total
2170size---for each of the object or archive files @var{objfile} in its
2171argument list. By default, one line of output is generated for each
2172object file or each module in an archive.
2173
2174@var{objfile}@dots{} are the object files to be examined.
2175If none are specified, the file @code{a.out} will be used.
2176
2177@c man end
2178
2179@c man begin OPTIONS size
2180
2181The command line options have the following meanings:
2182
2183@table @env
2184@item -A
2185@itemx -B
2186@itemx --format=@var{compatibility}
2187@cindex @command{size} display format
2188Using one of these options, you can choose whether the output from @sc{gnu}
2189@command{size} resembles output from System V @command{size} (using @option{-A},
2190or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
2191@option{--format=berkeley}). The default is the one-line format similar to
2192Berkeley's.
2193@c Bonus for doc-source readers: you can also say --format=strange (or
2194@c anything else that starts with 's') for sysv, and --format=boring (or
2195@c anything else that starts with 'b') for Berkeley.
2196
2197Here is an example of the Berkeley (default) format of output from
2198@command{size}:
2199@smallexample
2200$ size --format=Berkeley ranlib size
2201text data bss dec hex filename
2202294880 81920 11592 388392 5ed28 ranlib
2203294880 81920 11888 388688 5ee50 size
2204@end smallexample
2205
2206@noindent
2207This is the same data, but displayed closer to System V conventions:
2208
2209@smallexample
2210$ size --format=SysV ranlib size
2211ranlib :
2212section size addr
2213.text 294880 8192
2214.data 81920 303104
2215.bss 11592 385024
2216Total 388392
2217
2218
2219size :
2220section size addr
2221.text 294880 8192
2222.data 81920 303104
2223.bss 11888 385024
2224Total 388688
2225@end smallexample
2226
2227@item --help
2228Show a summary of acceptable arguments and options.
2229
2230@item -d
2231@itemx -o
2232@itemx -x
2233@itemx --radix=@var{number}
2234@cindex @command{size} number format
2235@cindex radix for section sizes
2236Using one of these options, you can control whether the size of each
2237section is given in decimal (@option{-d}, or @option{--radix=10}); octal
2238(@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
2239@option{--radix=16}). In @option{--radix=@var{number}}, only the three
2240values (8, 10, 16) are supported. The total size is always given in two
2241radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
2242octal and hexadecimal if you're using @option{-o}.
2243
2244@item --common
2245Print total size of common symbols in each file. When using Berkeley
2246format these are included in the bss size.
2247
2248@item -t
2249@itemx --totals
2250Show totals of all objects listed (Berkeley format listing mode only).
2251
2252@item --target=@var{bfdname}
2253@cindex object code format
2254Specify that the object-code format for @var{objfile} is
2255@var{bfdname}. This option may not be necessary; @command{size} can
2256automatically recognize many formats.
2257@xref{Target Selection}, for more information.
2258
2259@item -V
2260@itemx --version
2261Display the version number of @command{size}.
2262@end table
2263
2264@c man end
2265
2266@ignore
2267@c man begin SEEALSO size
2268ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2269@c man end
2270@end ignore
2271
2272@node strings
2273@chapter strings
2274@kindex strings
2275@cindex listings strings
2276@cindex printing strings
2277@cindex strings, printing
2278
2279@c man title strings print the strings of printable characters in files.
2280
2281@smallexample
2282@c man begin SYNOPSIS strings
2283strings [@option{-afov}] [@option{-}@var{min-len}]
2284 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2285 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2286 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2287 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2288 [@option{-T} @var{bfdname}] [@option{--target=}@var{bfdname}]
2289 [@option{--help}] [@option{--version}] @var{file}@dots{}
2290@c man end
2291@end smallexample
2292
2293@c man begin DESCRIPTION strings
2294
2295For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2296character sequences that are at least 4 characters long (or the number
2297given with the options below) and are followed by an unprintable
2298character. By default, it only prints the strings from the initialized
2299and loaded sections of object files; for other types of files, it prints
2300the strings from the whole file.
2301
2302@command{strings} is mainly useful for determining the contents of non-text
2303files.
2304
2305@c man end
2306
2307@c man begin OPTIONS strings
2308
2309@table @env
2310@item -a
2311@itemx --all
2312@itemx -
2313Do not scan only the initialized and loaded sections of object files;
2314scan the whole files.
2315
2316@item -f
2317@itemx --print-file-name
2318Print the name of the file before each string.
2319
2320@item --help
2321Print a summary of the program usage on the standard output and exit.
2322
2323@item -@var{min-len}
2324@itemx -n @var{min-len}
2325@itemx --bytes=@var{min-len}
2326Print sequences of characters that are at least @var{min-len} characters
2327long, instead of the default 4.
2328
2329@item -o
2330Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2331act like @samp{-t d} instead. Since we can not be compatible with both
2332ways, we simply chose one.
2333
2334@item -t @var{radix}
2335@itemx --radix=@var{radix}
2336Print the offset within the file before each string. The single
2337character argument specifies the radix of the offset---@samp{o} for
2338octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2339
2340@item -e @var{encoding}
2341@itemx --encoding=@var{encoding}
2342Select the character encoding of the strings that are to be found.
2343Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2344characters (ASCII, ISO 8859, etc., default), @samp{S} =
2345single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
234616-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2347littleendian. Useful for finding wide character strings.
2348
2349@item -T @var{bfdname}
2350@itemx --target=@var{bfdname}
2351@cindex object code format
2352Specify an object code format other than your system's default format.
2353@xref{Target Selection}, for more information.
2354
2355@item -v
2356@itemx --version
2357Print the program version number on the standard output and exit.
2358@end table
2359
2360@c man end
2361
2362@ignore
2363@c man begin SEEALSO strings
2364ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2365and the Info entries for @file{binutils}.
2366@c man end
2367@end ignore
2368
2369@node strip
2370@chapter strip
2371
2372@kindex strip
2373@cindex removing symbols
2374@cindex discarding symbols
2375@cindex symbols, discarding
2376
2377@c man title strip Discard symbols from object files.
2378
2379@smallexample
2380@c man begin SYNOPSIS strip
2381strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2382 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2383 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2384 [@option{-s}|@option{--strip-all}]
2385 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2386 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2387 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2388 [@option{-w}|@option{--wildcard}]
2389 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2390 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2391 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2392 [@option{--keep-file-symbols}]
2393 [@option{--only-keep-debug}]
2394 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2395 [@option{--help}] [@option{--info}]
2396 @var{objfile}@dots{}
2397@c man end
2398@end smallexample
2399
2400@c man begin DESCRIPTION strip
2401
2402@sc{gnu} @command{strip} discards all symbols from object files
2403@var{objfile}. The list of object files may include archives.
2404At least one object file must be given.
2405
2406@command{strip} modifies the files named in its argument,
2407rather than writing modified copies under different names.
2408
2409@c man end
2410
2411@c man begin OPTIONS strip
2412
2413@table @env
2414@item -F @var{bfdname}
2415@itemx --target=@var{bfdname}
2416Treat the original @var{objfile} as a file with the object
2417code format @var{bfdname}, and rewrite it in the same format.
2418@xref{Target Selection}, for more information.
2419
2420@item --help
2421Show a summary of the options to @command{strip} and exit.
2422
2423@item --info
2424Display a list showing all architectures and object formats available.
2425
2426@item -I @var{bfdname}
2427@itemx --input-target=@var{bfdname}
2428Treat the original @var{objfile} as a file with the object
2429code format @var{bfdname}.
2430@xref{Target Selection}, for more information.
2431
2432@item -O @var{bfdname}
2433@itemx --output-target=@var{bfdname}
2434Replace @var{objfile} with a file in the output format @var{bfdname}.
2435@xref{Target Selection}, for more information.
2436
2437@item -R @var{sectionname}
2438@itemx --remove-section=@var{sectionname}
2439Remove any section named @var{sectionname} from the output file. This
2440option may be given more than once. Note that using this option
2441inappropriately may make the output file unusable.
2442
2443@item -s
2444@itemx --strip-all
2445Remove all symbols.
2446
2447@item -g
2448@itemx -S
2449@itemx -d
2450@itemx --strip-debug
2451Remove debugging symbols only.
2452
2453@item --strip-unneeded
2454Remove all symbols that are not needed for relocation processing.
2455
2456@item -K @var{symbolname}
2457@itemx --keep-symbol=@var{symbolname}
2458When stripping symbols, keep symbol @var{symbolname} even if it would
2459normally be stripped. This option may be given more than once.
2460
2461@item -N @var{symbolname}
2462@itemx --strip-symbol=@var{symbolname}
2463Remove symbol @var{symbolname} from the source file. This option may be
2464given more than once, and may be combined with strip options other than
2465@option{-K}.
2466
2467@item -o @var{file}
2468Put the stripped output in @var{file}, rather than replacing the
2469existing file. When this argument is used, only one @var{objfile}
2470argument may be specified.
2471
2472@item -p
2473@itemx --preserve-dates
2474Preserve the access and modification dates of the file.
2475
2476@item -w
2477@itemx --wildcard
2478Permit regular expressions in @var{symbolname}s used in other command
2479line options. The question mark (?), asterisk (*), backslash (\) and
2480square brackets ([]) operators can be used anywhere in the symbol
2481name. If the first character of the symbol name is the exclamation
2482point (!) then the sense of the switch is reversed for that symbol.
2483For example:
2484
2485@smallexample
2486 -w -K !foo -K fo*
2487@end smallexample
2488
2489would cause strip to only keep symbols that start with the letters
2490``fo'', but to discard the symbol ``foo''.
2491
2492@item -x
2493@itemx --discard-all
2494Remove non-global symbols.
2495
2496@item -X
2497@itemx --discard-locals
2498Remove compiler-generated local symbols.
2499(These usually start with @samp{L} or @samp{.}.)
2500
2501@item --keep-file-symbols
2502When stripping a file, perhaps with @option{--strip-debug} or
2503@option{--strip-unneeded}, retain any symbols specifying source file names,
2504which would otherwise get stripped.
2505
2506@item --only-keep-debug
2507Strip a file, removing contents of any sections that would not be
2508stripped by @option{--strip-debug} and leaving the debugging sections
2509intact. In ELF files, this preserves all note sections in the output.
2510
2511The intention is that this option will be used in conjunction with
2512@option{--add-gnu-debuglink} to create a two part executable. One a
2513stripped binary which will occupy less space in RAM and in a
2514distribution and the second a debugging information file which is only
2515needed if debugging abilities are required. The suggested procedure
2516to create these files is as follows:
2517
2518@enumerate
2519@item Link the executable as normal. Assuming that is is called
2520@code{foo} then...
2521@item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2522create a file containing the debugging info.
2523@item Run @code{objcopy --strip-debug foo} to create a
2524stripped executable.
2525@item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2526to add a link to the debugging info into the stripped executable.
2527@end enumerate
2528
2529Note---the choice of @code{.dbg} as an extension for the debug info
2530file is arbitrary. Also the @code{--only-keep-debug} step is
2531optional. You could instead do this:
2532
2533@enumerate
2534@item Link the executable as normal.
2535@item Copy @code{foo} to @code{foo.full}
2536@item Run @code{strip --strip-debug foo}
2537@item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2538@end enumerate
2539
2540i.e., the file pointed to by the @option{--add-gnu-debuglink} can be the
2541full executable. It does not have to be a file created by the
2542@option{--only-keep-debug} switch.
2543
2544Note---this switch is only intended for use on fully linked files. It
2545does not make sense to use it on object files where the debugging
2546information may be incomplete. Besides the gnu_debuglink feature
2547currently only supports the presence of one filename containing
2548debugging information, not multiple filenames on a one-per-object-file
2549basis.
2550
2551@item -V
2552@itemx --version
2553Show the version number for @command{strip}.
2554
2555@item -v
2556@itemx --verbose
2557Verbose output: list all object files modified. In the case of
2558archives, @samp{strip -v} lists all members of the archive.
2559@end table
2560
2561@c man end
2562
2563@ignore
2564@c man begin SEEALSO strip
2565the Info entries for @file{binutils}.
2566@c man end
2567@end ignore
2568
2569@node c++filt, addr2line, strip, Top
2570@chapter c++filt
2571
2572@kindex c++filt
2573@cindex demangling C++ symbols
2574
2575@c man title cxxfilt Demangle C++ and Java symbols.
2576
2577@smallexample
2578@c man begin SYNOPSIS cxxfilt
2579c++filt [@option{-_}|@option{--strip-underscores}]
2580 [@option{-n}|@option{--no-strip-underscores}]
2581 [@option{-p}|@option{--no-params}]
2582 [@option{-t}|@option{--types}]
2583 [@option{-i}|@option{--no-verbose}]
2584 [@option{-s} @var{format}|@option{--format=}@var{format}]
2585 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2586@c man end
2587@end smallexample
2588
2589@c man begin DESCRIPTION cxxfilt
2590
2591@kindex cxxfilt
2592The C++ and Java languages provide function overloading, which means
2593that you can write many functions with the same name, providing that
2594each function takes parameters of different types. In order to be
2595able to distinguish these similarly named functions C++ and Java
2596encode them into a low-level assembler name which uniquely identifies
2597each different version. This process is known as @dfn{mangling}. The
2598@command{c++filt}
2599@footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2600MS-DOS this program is named @command{CXXFILT}.}
2601program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2602names into user-level names so that they can be read.
2603
2604Every alphanumeric word (consisting of letters, digits, underscores,
2605dollars, or periods) seen in the input is a potential mangled name.
2606If the name decodes into a C++ name, the C++ name replaces the
2607low-level name in the output, otherwise the original word is output.
2608In this way you can pass an entire assembler source file, containing
2609mangled names, through @command{c++filt} and see the same source file
2610containing demangled names.
2611
2612You can also use @command{c++filt} to decipher individual symbols by
2613passing them on the command line:
2614
2615@example
2616c++filt @var{symbol}
2617@end example
2618
2619If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2620names from the standard input instead. All the results are printed on
2621the standard output. The difference between reading names from the
2622command line versus reading names from the standard input is that
2623command line arguments are expected to be just mangled names and no
2624checking is performed to separate them from surrounding text. Thus
2625for example:
2626
2627@smallexample
2628c++filt -n _Z1fv
2629@end smallexample
2630
2631will work and demangle the name to ``f()'' whereas:
2632
2633@smallexample
2634c++filt -n _Z1fv,
2635@end smallexample
2636
2637will not work. (Note the extra comma at the end of the mangled
2638name which makes it invalid). This command however will work:
2639
2640@smallexample
2641echo _Z1fv, | c++filt -n
2642@end smallexample
2643
2644and will display ``f(),'', i.e., the demangled name followed by a
2645trailing comma. This behaviour is because when the names are read
2646from the standard input it is expected that they might be part of an
2647assembler source file where there might be extra, extraneous
2648characters trailing after a mangled name. For example:
2649
2650@smallexample
2651 .type _Z1fv, @@function
2652@end smallexample
2653
2654@c man end
2655
2656@c man begin OPTIONS cxxfilt
2657
2658@table @env
2659@item -_
2660@itemx --strip-underscores
2661On some systems, both the C and C++ compilers put an underscore in front
2662of every name. For example, the C name @code{foo} gets the low-level
2663name @code{_foo}. This option removes the initial underscore. Whether
2664@command{c++filt} removes the underscore by default is target dependent.
2665
2666@item -j
2667@itemx --java
2668Prints demangled names using Java syntax. The default is to use C++
2669syntax.
2670
2671@item -n
2672@itemx --no-strip-underscores
2673Do not remove the initial underscore.
2674
2675@item -p
2676@itemx --no-params
2677When demangling the name of a function, do not display the types of
2678the function's parameters.
2679
2680@item -t
2681@itemx --types
2682Attempt to demangle types as well as function names. This is disabled
2683by default since mangled types are normally only used internally in
2684the compiler, and they can be confused with non-mangled names. For example,
2685a function called ``a'' treated as a mangled type name would be
2686demangled to ``signed char''.
2687
2688@item -i
2689@itemx --no-verbose
2690Do not include implementation details (if any) in the demangled
2691output.
2692
2693@item -s @var{format}
2694@itemx --format=@var{format}
2695@command{c++filt} can decode various methods of mangling, used by
2696different compilers. The argument to this option selects which
2697method it uses:
2698
2699@table @code
2700@item auto
2701Automatic selection based on executable (the default method)
2702@item gnu
2703the one used by the @sc{gnu} C++ compiler (g++)
2704@item lucid
2705the one used by the Lucid compiler (lcc)
2706@item arm
2707the one specified by the C++ Annotated Reference Manual
2708@item hp
2709the one used by the HP compiler (aCC)
2710@item edg
2711the one used by the EDG compiler
2712@item gnu-v3
2713the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2714@item java
2715the one used by the @sc{gnu} Java compiler (gcj)
2716@item gnat
2717the one used by the @sc{gnu} Ada compiler (GNAT).
2718@end table
2719
2720@item --help
2721Print a summary of the options to @command{c++filt} and exit.
2722
2723@item --version
2724Print the version number of @command{c++filt} and exit.
2725@end table
2726
2727@c man end
2728
2729@ignore
2730@c man begin SEEALSO cxxfilt
2731the Info entries for @file{binutils}.
2732@c man end
2733@end ignore
2734
2735@quotation
2736@emph{Warning:} @command{c++filt} is a new utility, and the details of its
2737user interface are subject to change in future releases. In particular,
2738a command-line option may be required in the future to decode a name
2739passed as an argument on the command line; in other words,
2740
2741@example
2742c++filt @var{symbol}
2743@end example
2744
2745@noindent
2746may in a future release become
2747
2748@example
2749c++filt @var{option} @var{symbol}
2750@end example
2751@end quotation
2752
2753@node addr2line
2754@chapter addr2line
2755
2756@kindex addr2line
2757@cindex address to file name and line number
2758
2759@c man title addr2line convert addresses into file names and line numbers.
2760
2761@smallexample
2762@c man begin SYNOPSIS addr2line
2763addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2764 [@option{-C}|@option{--demangle}[=@var{style}]]
2765 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2766 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2767 [@option{-i}|@option{--inlines}]
2768 [@option{-j}|@option{--section=}@var{name}]
2769 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2770 [addr addr @dots{}]
2771@c man end
2772@end smallexample
2773
2774@c man begin DESCRIPTION addr2line
2775
2776@command{addr2line} translates addresses into file names and line numbers.
2777Given an address in an executable or an offset in a section of a relocatable
2778object, it uses the debugging information to figure out which file name and
2779line number are associated with it.
2780
2781The executable or relocatable object to use is specified with the @option{-e}
2782option. The default is the file @file{a.out}. The section in the relocatable
2783object to use is specified with the @option{-j} option.
2784
2785@command{addr2line} has two modes of operation.
2786
2787In the first, hexadecimal addresses are specified on the command line,
2788and @command{addr2line} displays the file name and line number for each
2789address.
2790
2791In the second, @command{addr2line} reads hexadecimal addresses from
2792standard input, and prints the file name and line number for each
2793address on standard output. In this mode, @command{addr2line} may be used
2794in a pipe to convert dynamically chosen addresses.
2795
2796The format of the output is @samp{FILENAME:LINENO}. The file name and
2797line number for each address is printed on a separate line. If the
2798@command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2799preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2800containing the address.
2801
2802If the file name or function name can not be determined,
2803@command{addr2line} will print two question marks in their place. If the
2804line number can not be determined, @command{addr2line} will print 0.
2805
2806@c man end
2807
2808@c man begin OPTIONS addr2line
2809
2810The long and short forms of options, shown here as alternatives, are
2811equivalent.
2812
2813@table @env
2814@item -b @var{bfdname}
2815@itemx --target=@var{bfdname}
2816@cindex object code format
2817Specify that the object-code format for the object files is
2818@var{bfdname}.
2819
2820@item -C
2821@itemx --demangle[=@var{style}]
2822@cindex demangling in objdump
2823Decode (@dfn{demangle}) low-level symbol names into user-level names.
2824Besides removing any initial underscore prepended by the system, this
2825makes C++ function names readable. Different compilers have different
2826mangling styles. The optional demangling style argument can be used to
2827choose an appropriate demangling style for your compiler. @xref{c++filt},
2828for more information on demangling.
2829
2830@item -e @var{filename}
2831@itemx --exe=@var{filename}
2832Specify the name of the executable for which addresses should be
2833translated. The default file is @file{a.out}.
2834
2835@item -f
2836@itemx --functions
2837Display function names as well as file and line number information.
2838
2839@item -s
2840@itemx --basenames
2841Display only the base of each file name.
2842
2843@item -i
2844@itemx --inlines
2845If the address belongs to a function that was inlined, the source
2846information for all enclosing scopes back to the first non-inlined
2847function will also be printed. For example, if @code{main} inlines
2848@code{callee1} which inlines @code{callee2}, and address is from
2849@code{callee2}, the source information for @code{callee1} and @code{main}
2850will also be printed.
2851
2852@item -j
2853@itemx --section
2854Read offsets relative to the specified section instead of absolute addresses.
2855@end table
2856
2857@c man end
2858
2859@ignore
2860@c man begin SEEALSO addr2line
2861Info entries for @file{binutils}.
2862@c man end
2863@end ignore
2864
2865@node nlmconv
2866@chapter nlmconv
2867
2868@command{nlmconv} converts a relocatable object file into a NetWare
2869Loadable Module.
2870
2871@ignore
2872@command{nlmconv} currently works with @samp{i386} object
2873files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2874object files in @sc{elf}, or @code{a.out} format@footnote{
2875@command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2876format in the Binary File Descriptor library. It has only been tested
2877with the above formats.}.
2878@end ignore
2879
2880@quotation
2881@emph{Warning:} @command{nlmconv} is not always built as part of the binary
2882utilities, since it is only useful for NLM targets.
2883@end quotation
2884
2885@c man title nlmconv converts object code into an NLM.
2886
2887@smallexample
2888@c man begin SYNOPSIS nlmconv
2889nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2890 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2891 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2892 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2893 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2894 @var{infile} @var{outfile}
2895@c man end
2896@end smallexample
2897
2898@c man begin DESCRIPTION nlmconv
2899
2900@command{nlmconv} converts the relocatable @samp{i386} object file
2901@var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2902reading @var{headerfile} for NLM header information. For instructions
2903on writing the NLM command file language used in header files, see the
2904@samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2905Development and Tools Overview}, which is part of the NLM Software
2906Developer's Kit (``NLM SDK''), available from Novell, Inc.
2907@command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2908@var{infile};
2909@ifclear man
2910see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2911@end ifclear
2912
2913@command{nlmconv} can perform a link step. In other words, you can list
2914more than one object file for input if you list them in the definitions
2915file (rather than simply specifying one input file on the command line).
2916In this case, @command{nlmconv} calls the linker for you.
2917
2918@c man end
2919
2920@c man begin OPTIONS nlmconv
2921
2922@table @env
2923@item -I @var{bfdname}
2924@itemx --input-target=@var{bfdname}
2925Object format of the input file. @command{nlmconv} can usually determine
2926the format of a given file (so no default is necessary).
2927@xref{Target Selection}, for more information.
2928
2929@item -O @var{bfdname}
2930@itemx --output-target=@var{bfdname}
2931Object format of the output file. @command{nlmconv} infers the output
2932format based on the input format, e.g. for a @samp{i386} input file the
2933output format is @samp{nlm32-i386}.
2934@xref{Target Selection}, for more information.
2935
2936@item -T @var{headerfile}
2937@itemx --header-file=@var{headerfile}
2938Reads @var{headerfile} for NLM header information. For instructions on
2939writing the NLM command file language used in header files, see@ see the
2940@samp{linkers} section, of the @cite{NLM Development and Tools
2941Overview}, which is part of the NLM Software Developer's Kit, available
2942from Novell, Inc.
2943
2944@item -d
2945@itemx --debug
2946Displays (on standard error) the linker command line used by @command{nlmconv}.
2947
2948@item -l @var{linker}
2949@itemx --linker=@var{linker}
2950Use @var{linker} for any linking. @var{linker} can be an absolute or a
2951relative pathname.
2952
2953@item -h
2954@itemx --help
2955Prints a usage summary.
2956
2957@item -V
2958@itemx --version
2959Prints the version number for @command{nlmconv}.
2960@end table
2961
2962@c man end
2963
2964@ignore
2965@c man begin SEEALSO nlmconv
2966the Info entries for @file{binutils}.
2967@c man end
2968@end ignore
2969
2970@node windmc
2971@chapter windmc
2972
2973@command{windmc} may be used to generator Windows message resources.
2974
2975@quotation
2976@emph{Warning:} @command{windmc} is not always built as part of the binary
2977utilities, since it is only useful for Windows targets.
2978@end quotation
2979
2980@c man title windmc generates Windows message resources.
2981
2982@smallexample
2983@c man begin SYNOPSIS windres
2984windmc [options] input-file
2985@c man end
2986@end smallexample
2987
2988@c man begin DESCRIPTION windmc
2989
2990@command{windmc} reads message definitions from an input file (.mc) and
2991translate them into a set of output files. The output files may be of
2992four kinds:
2993
2994@table @code
2995@item h
2996A C header file containing the message definitions.
2997
2998@item rc
2999A resource file compilable by the @command{windres} tool.
3000
3001@item bin
3002One or more binary files containing the resource data for a specific
3003message language.
3004
3005@item dbg
3006A C include file that maps message id's to their symbolic name.
3007@end table
3008
3009The exact description of these different formats is available in
3010documentation from Microsoft.
3011
3012When @command{windmc} converts from the @code{mc} format to the @code{bin}
3013format, @code{rc}, @code{h}, and optional @code{dbg} it is acting like the
3014Windows Message Compiler.
3015
3016@c man end
3017
3018@c man begin OPTIONS windmc
3019
3020@table @env
3021@item -a
3022@itemx --ascii_in
3023Specifies that the input file specified is ANSI. This is the default
3024behaviour.
3025
3026@item -A
3027@itemx --ascii_out
3028Specifies that messages in the output @code{bin} files should be in ANSI
3029format.
3030
3031@item -b
3032@itemx --binprefix
3033Specifies that @code{bin} filenames should have to be prefixed by the
3034basename of the source file.
3035
3036@item -c
3037@itemx --customflag
3038Sets the customer bit in all message id's.
3039
3040@item -C @var{codepage}
3041@itemx --codepage_in @var{codepage}
3042Sets the default codepage to be used to convert input file to UTF16. The
3043default is ocdepage 1252.
3044
3045@item -d
3046@itemx --decimal_values
3047Outputs the constants in the header file in decimal. Default is using
3048hexadecimal output.
3049
3050@item -e @var{ext}
3051@itemx --extension @var{ext}
3052The extension for the header file. The default is .h extension.
3053
3054@item -F @var{target}
3055@itemx --target @var{target}
3056Specify the BFD format to use for a bin file as output. This
3057is a BFD target name; you can use the @option{--help} option to see a list
3058of supported targets. Normally @command{windmc} will use the default
3059format, which is the first one listed by the @option{--help} option.
3060@ifclear man
3061@ref{Target Selection}.
3062@end ifclear
3063
3064@item -h @var{path}
3065@itemx --headerdir @var{path}
3066The target directory of the generated header file. The default is the
3067current directory.
3068
3069@item -H
3070@itemx --help
3071Displays a list of command line options and then exits.
3072
3073@item -m @var{characters}
3074@itemx --maxlength @var{characters}
3075Instructs @command{windmc} to generate a warning if the length
3076of any message exceeds the number specified.
3077
3078@item -n
3079@itemx --nullterminate
3080Terminate message text in @code{bin} files by zero. By default they are
3081terminated by CR/LF.
3082
3083@item -o
3084@itemx --hresult_use
3085Not yet implemented. Instructs @code{windmc} to generate an OLE2 header
3086file, using HRESULT definitions. Status codes are used if the flag is not
3087specified.
3088
3089@item -O @var{codepage}
3090@itemx --codepage_out @var{codepage}
3091Sets the default codepage to be used to output text files. The default
3092is ocdepage 1252.
3093
3094@item -r @var{path}
3095@itemx --rcdir @var{path}
3096The target directory for the generated @code{rc} script and the generated
3097@code{bin} files that the resource compiler script includes. The default
3098is the current directory.
3099
3100@item -u
3101@itemx --unicode_in
3102Specifies that the input file is UTF16.
3103
3104@item -U
3105@itemx --unicode_out
3106Specifies that messages in the output @code{bin} file should be in UTF16
3107format. This is the default behaviour.
3108
3109@item -v
3110@item --verbose
3111Enable verbose mode.
3112
3113@item -V
3114@item --version
3115Prints the version number for @command{windmc}.
3116
3117@item -x @var{path}
3118@itemx --xdgb @var{path}
3119The path of the @code{dbg} C include file that maps message id's to the
3120symbolic name. No such file is generated without specifying the switch.
3121@end table
3122
3123@c man end
3124
3125@ignore
3126@c man begin SEEALSO windmc
3127the Info entries for @file{binutils}.
3128@c man end
3129@end ignore
3130
3131@node windres
3132@chapter windres
3133
3134@command{windres} may be used to manipulate Windows resources.
3135
3136@quotation
3137@emph{Warning:} @command{windres} is not always built as part of the binary
3138utilities, since it is only useful for Windows targets.
3139@end quotation
3140
3141@c man title windres manipulate Windows resources.
3142
3143@smallexample
3144@c man begin SYNOPSIS windres
3145windres [options] [input-file] [output-file]
3146@c man end
3147@end smallexample
3148
3149@c man begin DESCRIPTION windres
3150
3151@command{windres} reads resources from an input file and copies them into
3152an output file. Either file may be in one of three formats:
3153
3154@table @code
3155@item rc
3156A text format read by the Resource Compiler.
3157
3158@item res
3159A binary format generated by the Resource Compiler.
3160
3161@item coff
3162A COFF object or executable.
3163@end table
3164
3165The exact description of these different formats is available in
3166documentation from Microsoft.
3167
3168When @command{windres} converts from the @code{rc} format to the @code{res}
3169format, it is acting like the Windows Resource Compiler. When
3170@command{windres} converts from the @code{res} format to the @code{coff}
3171format, it is acting like the Windows @code{CVTRES} program.
3172
3173When @command{windres} generates an @code{rc} file, the output is similar
3174but not identical to the format expected for the input. When an input
3175@code{rc} file refers to an external filename, an output @code{rc} file
3176will instead include the file contents.
3177
3178If the input or output format is not specified, @command{windres} will
3179guess based on the file name, or, for the input file, the file contents.
3180A file with an extension of @file{.rc} will be treated as an @code{rc}
3181file, a file with an extension of @file{.res} will be treated as a
3182@code{res} file, and a file with an extension of @file{.o} or
3183@file{.exe} will be treated as a @code{coff} file.
3184
3185If no output file is specified, @command{windres} will print the resources
3186in @code{rc} format to standard output.
3187
3188The normal use is for you to write an @code{rc} file, use @command{windres}
3189to convert it to a COFF object file, and then link the COFF file into
3190your application. This will make the resources described in the
3191@code{rc} file available to Windows.
3192
3193@c man end
3194
3195@c man begin OPTIONS windres
3196
3197@table @env
3198@item -i @var{filename}
3199@itemx --input @var{filename}
3200The name of the input file. If this option is not used, then
3201@command{windres} will use the first non-option argument as the input file
3202name. If there are no non-option arguments, then @command{windres} will
3203read from standard input. @command{windres} can not read a COFF file from
3204standard input.
3205
3206@item -o @var{filename}
3207@itemx --output @var{filename}
3208The name of the output file. If this option is not used, then
3209@command{windres} will use the first non-option argument, after any used
3210for the input file name, as the output file name. If there is no
3211non-option argument, then @command{windres} will write to standard output.
3212@command{windres} can not write a COFF file to standard output. Note,
3213for compatibility with @command{rc} the option @option{-fo} is also
3214accepted, but its use is not recommended.
3215
3216@item -J @var{format}
3217@itemx --input-format @var{format}
3218The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
3219@samp{coff}. If no input format is specified, @command{windres} will
3220guess, as described above.
3221
3222@item -O @var{format}
3223@itemx --output-format @var{format}
3224The output format to generate. @var{format} may be @samp{res},
3225@samp{rc}, or @samp{coff}. If no output format is specified,
3226@command{windres} will guess, as described above.
3227
3228@item -F @var{target}
3229@itemx --target @var{target}
3230Specify the BFD format to use for a COFF file as input or output. This
3231is a BFD target name; you can use the @option{--help} option to see a list
3232of supported targets. Normally @command{windres} will use the default
3233format, which is the first one listed by the @option{--help} option.
3234@ifclear man
3235@ref{Target Selection}.
3236@end ifclear
3237
3238@item --preprocessor @var{program}
3239When @command{windres} reads an @code{rc} file, it runs it through the C
3240preprocessor first. This option may be used to specify the preprocessor
3241to use, including any leading arguments. The default preprocessor
3242argument is @code{gcc -E -xc-header -DRC_INVOKED}.
3243
3244@item -I @var{directory}
3245@itemx --include-dir @var{directory}
3246Specify an include directory to use when reading an @code{rc} file.
3247@command{windres} will pass this to the preprocessor as an @option{-I}
3248option. @command{windres} will also search this directory when looking for
3249files named in the @code{rc} file. If the argument passed to this command
3250matches any of the supported @var{formats} (as described in the @option{-J}
3251option), it will issue a deprecation warning, and behave just like the
3252@option{-J} option. New programs should not use this behaviour. If a
3253directory happens to match a @var{format}, simple prefix it with @samp{./}
3254to disable the backward compatibility.
3255
3256@item -D @var{target}
3257@itemx --define @var{sym}[=@var{val}]
3258Specify a @option{-D} option to pass to the preprocessor when reading an
3259@code{rc} file.
3260
3261@item -U @var{target}
3262@itemx --undefine @var{sym}
3263Specify a @option{-U} option to pass to the preprocessor when reading an
3264@code{rc} file.
3265
3266@item -r
3267Ignored for compatibility with rc.
3268
3269@item -v
3270Enable verbose mode. This tells you what the preprocessor is if you
3271didn't specify one.
3272
3273@item -c @var{val}
3274@item --codepage @var{val}
3275Specify the default codepage to use when reading an @code{rc} file.
3276@var{val} should be a hexadecimal prefixed by @samp{0x} or decimal
3277codepage code. The valid range is from zero up to 0xffff, but the
3278validity of the codepage is host and configuration dependent.
3279
3280@item -l @var{val}
3281@item --language @var{val}
3282Specify the default language to use when reading an @code{rc} file.
3283@var{val} should be a hexadecimal language code. The low eight bits are
3284the language, and the high eight bits are the sublanguage.
3285
3286@item --use-temp-file
3287Use a temporary file to instead of using popen to read the output of
3288the preprocessor. Use this option if the popen implementation is buggy
3289on the host (eg., certain non-English language versions of Windows 95 and
3290Windows 98 are known to have buggy popen where the output will instead
3291go the console).
3292
3293@item --no-use-temp-file
3294Use popen, not a temporary file, to read the output of the preprocessor.
3295This is the default behaviour.
3296
3297@item -h
3298@item --help
3299Prints a usage summary.
3300
3301@item -V
3302@item --version
3303Prints the version number for @command{windres}.
3304
3305@item --yydebug
3306If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
3307this will turn on parser debugging.
3308@end table
3309
3310@c man end
3311
3312@ignore
3313@c man begin SEEALSO windres
3314the Info entries for @file{binutils}.
3315@c man end
3316@end ignore
3317
3318@node dlltool
3319@chapter dlltool
3320@cindex DLL
3321@kindex dlltool
3322
3323@command{dlltool} is used to create the files needed to create dynamic
3324link libraries (DLLs) on systems which understand PE format image
3325files such as Windows. A DLL contains an export table which contains
3326information that the runtime loader needs to resolve references from a
3327referencing program.
3328
3329The export table is generated by this program by reading in a
3330@file{.def} file or scanning the @file{.a} and @file{.o} files which
3331will be in the DLL. A @file{.o} file can contain information in
3332special @samp{.drectve} sections with export information.
3333
3334@quotation
3335@emph{Note:} @command{dlltool} is not always built as part of the
3336binary utilities, since it is only useful for those targets which
3337support DLLs.
3338@end quotation
3339
3340@c man title dlltool Create files needed to build and use DLLs.
3341
3342@smallexample
3343@c man begin SYNOPSIS dlltool
3344dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
3345 [@option{-b}|@option{--base-file} @var{base-file-name}]
3346 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
3347 [@option{-z}|@option{--output-def} @var{def-file-name}]
3348 [@option{-l}|@option{--output-lib} @var{library-file-name}]
3349 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
3350 [@option{--exclude-symbols} @var{list}]
3351 [@option{--no-default-excludes}]
3352 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
3353 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
3354 [@option{-a}|@option{--add-indirect}]
3355 [@option{-U}|@option{--add-underscore}] [@option{--add-stdcall-underscore}]
3356 [@option{-k}|@option{--kill-at}] [@option{-A}|@option{--add-stdcall-alias}]
3357 [@option{-p}|@option{--ext-prefix-alias} @var{prefix}]
3358 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
3359 [@option{-n}|@option{--nodelete}] [@option{-t}|@option{--temp-prefix} @var{prefix}]
3360 [@option{-v}|@option{--verbose}]
3361 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
3362 [object-file @dots{}]
3363@c man end
3364@end smallexample
3365
3366@c man begin DESCRIPTION dlltool
3367
3368@command{dlltool} reads its inputs, which can come from the @option{-d} and
3369@option{-b} options as well as object files specified on the command
3370line. It then processes these inputs and if the @option{-e} option has
3371been specified it creates a exports file. If the @option{-l} option
3372has been specified it creates a library file and if the @option{-z} option
3373has been specified it creates a def file. Any or all of the @option{-e},
3374@option{-l} and @option{-z} options can be present in one invocation of
3375dlltool.
3376
3377When creating a DLL, along with the source for the DLL, it is necessary
3378to have three other files. @command{dlltool} can help with the creation of
3379these files.
3380
3381The first file is a @file{.def} file which specifies which functions are
3382exported from the DLL, which functions the DLL imports, and so on. This
3383is a text file and can be created by hand, or @command{dlltool} can be used
3384to create it using the @option{-z} option. In this case @command{dlltool}
3385will scan the object files specified on its command line looking for
3386those functions which have been specially marked as being exported and
3387put entries for them in the @file{.def} file it creates.
3388
3389In order to mark a function as being exported from a DLL, it needs to
3390have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
3391section of the object file. This can be done in C by using the
3392asm() operator:
3393
3394@smallexample
3395 asm (".section .drectve");
3396 asm (".ascii \"-export:my_func\"");
3397
3398 int my_func (void) @{ @dots{} @}
3399@end smallexample
3400
3401The second file needed for DLL creation is an exports file. This file
3402is linked with the object files that make up the body of the DLL and it
3403handles the interface between the DLL and the outside world. This is a
3404binary file and it can be created by giving the @option{-e} option to
3405@command{dlltool} when it is creating or reading in a @file{.def} file.
3406
3407The third file needed for DLL creation is the library file that programs
3408will link with in order to access the functions in the DLL. This file
3409can be created by giving the @option{-l} option to dlltool when it
3410is creating or reading in a @file{.def} file.
3411
3412@command{dlltool} builds the library file by hand, but it builds the
3413exports file by creating temporary files containing assembler statements
3414and then assembling these. The @option{-S} command line option can be
3415used to specify the path to the assembler that dlltool will use,
3416and the @option{-f} option can be used to pass specific flags to that
3417assembler. The @option{-n} can be used to prevent dlltool from deleting
3418these temporary assembler files when it is done, and if @option{-n} is
3419specified twice then this will prevent dlltool from deleting the
3420temporary object files it used to build the library.
3421
3422Here is an example of creating a DLL from a source file @samp{dll.c} and
3423also creating a program (from an object file called @samp{program.o})
3424that uses that DLL:
3425
3426@smallexample
3427 gcc -c dll.c
3428 dlltool -e exports.o -l dll.lib dll.o
3429 gcc dll.o exports.o -o dll.dll
3430 gcc program.o dll.lib -o program
3431@end smallexample
3432
3433@c man end
3434
3435@c man begin OPTIONS dlltool
3436
3437The command line options have the following meanings:
3438
3439@table @env
3440
3441@item -d @var{filename}
3442@itemx --input-def @var{filename}
3443@cindex input .def file
3444Specifies the name of a @file{.def} file to be read in and processed.
3445
3446@item -b @var{filename}
3447@itemx --base-file @var{filename}
3448@cindex base files
3449Specifies the name of a base file to be read in and processed. The
3450contents of this file will be added to the relocation section in the
3451exports file generated by dlltool.
3452
3453@item -e @var{filename}
3454@itemx --output-exp @var{filename}
3455Specifies the name of the export file to be created by dlltool.
3456
3457@item -z @var{filename}
3458@itemx --output-def @var{filename}
3459Specifies the name of the @file{.def} file to be created by dlltool.
3460
3461@item -l @var{filename}
3462@itemx --output-lib @var{filename}
3463Specifies the name of the library file to be created by dlltool.
3464
3465@item --export-all-symbols
3466Treat all global and weak defined symbols found in the input object
3467files as symbols to be exported. There is a small list of symbols which
3468are not exported by default; see the @option{--no-default-excludes}
3469option. You may add to the list of symbols to not export by using the
3470@option{--exclude-symbols} option.
3471
3472@item --no-export-all-symbols
3473Only export symbols explicitly listed in an input @file{.def} file or in
3474@samp{.drectve} sections in the input object files. This is the default
3475behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
3476attributes in the source code.
3477
3478@item --exclude-symbols @var{list}
3479Do not export the symbols in @var{list}. This is a list of symbol names
3480separated by comma or colon characters. The symbol names should not
3481contain a leading underscore. This is only meaningful when
3482@option{--export-all-symbols} is used.
3483
3484@item --no-default-excludes
3485When @option{--export-all-symbols} is used, it will by default avoid
3486exporting certain special symbols. The current list of symbols to avoid
3487exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
3488@samp{impure_ptr}. You may use the @option{--no-default-excludes} option
3489to go ahead and export these special symbols. This is only meaningful
3490when @option{--export-all-symbols} is used.
3491
3492@item -S @var{path}
3493@itemx --as @var{path}
3494Specifies the path, including the filename, of the assembler to be used
3495to create the exports file.
3496
3497@item -f @var{options}
3498@itemx --as-flags @var{options}
3499Specifies any specific command line options to be passed to the
3500assembler when building the exports file. This option will work even if
3501the @option{-S} option is not used. This option only takes one argument,
3502and if it occurs more than once on the command line, then later
3503occurrences will override earlier occurrences. So if it is necessary to
3504pass multiple options to the assembler they should be enclosed in
3505double quotes.
3506
3507@item -D @var{name}
3508@itemx --dll-name @var{name}
3509Specifies the name to be stored in the @file{.def} file as the name of
3510the DLL when the @option{-e} option is used. If this option is not
3511present, then the filename given to the @option{-e} option will be
3512used as the name of the DLL.
3513
3514@item -m @var{machine}
3515@itemx -machine @var{machine}
3516Specifies the type of machine for which the library file should be
3517built. @command{dlltool} has a built in default type, depending upon how
3518it was created, but this option can be used to override that. This is
3519normally only useful when creating DLLs for an ARM processor, when the
3520contents of the DLL are actually encode using Thumb instructions.
3521
3522@item -a
3523@itemx --add-indirect
3524Specifies that when @command{dlltool} is creating the exports file it
3525should add a section which allows the exported functions to be
3526referenced without using the import library. Whatever the hell that
3527means!
3528
3529@item -U
3530@itemx --add-underscore
3531Specifies that when @command{dlltool} is creating the exports file it
3532should prepend an underscore to the names of @emph{all} exported symbols.
3533
3534@item --add-stdcall-underscore
3535Specifies that when @command{dlltool} is creating the exports file it
3536should prepend an underscore to the names of exported @emph{stdcall}
3537functions. Variable names and non-stdcall function names are not modified.
3538This option is useful when creating GNU-compatible import libs for third
3539party DLLs that were built with MS-Windows tools.
3540
3541@item -k
3542@itemx --kill-at
3543Specifies that when @command{dlltool} is creating the exports file it
3544should not append the string @samp{@@ <number>}. These numbers are
3545called ordinal numbers and they represent another way of accessing the
3546function in a DLL, other than by name.
3547
3548@item -A
3549@itemx --add-stdcall-alias
3550Specifies that when @command{dlltool} is creating the exports file it
3551should add aliases for stdcall symbols without @samp{@@ <number>}
3552in addition to the symbols with @samp{@@ <number>}.
3553
3554@item -p
3555@itemx --ext-prefix-alias @var{prefix}
3556Causes @command{dlltool} to create external aliases for all DLL
3557imports with the specified prefix. The aliases are created for both
3558external and import symbols with no leading underscore.
3559
3560@item -x
3561@itemx --no-idata4
3562Specifies that when @command{dlltool} is creating the exports and library
3563files it should omit the @code{.idata4} section. This is for compatibility
3564with certain operating systems.
3565
3566@item -c
3567@itemx --no-idata5
3568Specifies that when @command{dlltool} is creating the exports and library
3569files it should omit the @code{.idata5} section. This is for compatibility
3570with certain operating systems.
3571
3572@item -i
3573@itemx --interwork
3574Specifies that @command{dlltool} should mark the objects in the library
3575file and exports file that it produces as supporting interworking
3576between ARM and Thumb code.
3577
3578@item -n
3579@itemx --nodelete
3580Makes @command{dlltool} preserve the temporary assembler files it used to
3581create the exports file. If this option is repeated then dlltool will
3582also preserve the temporary object files it uses to create the library
3583file.
3584
3585@item -t @var{prefix}
3586@itemx --temp-prefix @var{prefix}
3587Makes @command{dlltool} use @var{prefix} when constructing the names of
3588temporary assembler and object files. By default, the temp file prefix
3589is generated from the pid.
3590
3591@item -v
3592@itemx --verbose
3593Make dlltool describe what it is doing.
3594
3595@item -h
3596@itemx --help
3597Displays a list of command line options and then exits.
3598
3599@item -V
3600@itemx --version
3601Displays dlltool's version number and then exits.
3602
3603@end table
3604
3605@c man end
3606
3607@menu
3608* def file format:: The format of the dlltool @file{.def} file
3609@end menu
3610
3611@node def file format
3612@section The format of the @command{dlltool} @file{.def} file
3613
3614A @file{.def} file contains any number of the following commands:
3615
3616@table @asis
3617
3618@item @code{NAME} @var{name} @code{[ ,} @var{base} @code{]}
3619The result is going to be named @var{name}@code{.exe}.
3620
3621@item @code{LIBRARY} @var{name} @code{[ ,} @var{base} @code{]}
3622The result is going to be named @var{name}@code{.dll}.
3623
3624@item @code{EXPORTS ( ( (} @var{name1} @code{[ = } @var{name2} @code{] ) | ( } @var{name1} @code{=} @var{module-name} @code{.} @var{external-name} @code{) )}
3625@item @code{[} @var{integer} @code{] [ NONAME ] [ CONSTANT ] [ DATA ] [ PRIVATE ] ) *}
3626Declares @var{name1} as an exported symbol from the DLL, with optional
3627ordinal number @var{integer}, or declares @var{name1} as an alias
3628(forward) of the function @var{external-name} in the DLL
3629@var{module-name}.
3630
3631@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{) ) *}
3632Declares that @var{external-name} or the exported function whose
3633ordinal number is @var{integer} is to be imported from the file
3634@var{module-name}. If @var{internal-name} is specified then this is
3635the name that the imported function will be referred to in the body of
3636the DLL.
3637
3638@item @code{DESCRIPTION} @var{string}
3639Puts @var{string} into the output @file{.exp} file in the
3640@code{.rdata} section.
3641
3642@item @code{STACKSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3643@item @code{HEAPSIZE} @var{number-reserve} @code{[, } @var{number-commit} @code{]}
3644Generates @code{--stack} or @code{--heap}
3645@var{number-reserve},@var{number-commit} in the output @code{.drectve}
3646section. The linker will see this and act upon it.
3647
3648@item @code{CODE} @var{attr} @code{+}
3649@item @code{DATA} @var{attr} @code{+}
3650@item @code{SECTIONS (} @var{section-name} @var{attr}@code{ + ) *}
3651Generates @code{--attr} @var{section-name} @var{attr} in the output
3652@code{.drectve} section, where @var{attr} is one of @code{READ},
3653@code{WRITE}, @code{EXECUTE} or @code{SHARED}. The linker will see
3654this and act upon it.
3655
3656@end table
3657
3658@ignore
3659@c man begin SEEALSO dlltool
3660The Info pages for @file{binutils}.
3661@c man end
3662@end ignore
3663
3664@node readelf
3665@chapter readelf
3666
3667@cindex ELF file information
3668@kindex readelf
3669
3670@c man title readelf Displays information about ELF files.
3671
3672@smallexample
3673@c man begin SYNOPSIS readelf
3674readelf [@option{-a}|@option{--all}]
3675 [@option{-h}|@option{--file-header}]
3676 [@option{-l}|@option{--program-headers}|@option{--segments}]
3677 [@option{-S}|@option{--section-headers}|@option{--sections}]
3678 [@option{-g}|@option{--section-groups}]
3679 [@option{-t}|@option{--section-details}]
3680 [@option{-e}|@option{--headers}]
3681 [@option{-s}|@option{--syms}|@option{--symbols}]
3682 [@option{-n}|@option{--notes}]
3683 [@option{-r}|@option{--relocs}]
3684 [@option{-u}|@option{--unwind}]
3685 [@option{-d}|@option{--dynamic}]
3686 [@option{-V}|@option{--version-info}]
3687 [@option{-A}|@option{--arch-specific}]
3688 [@option{-D}|@option{--use-dynamic}]
3689 [@option{-x} <number or name>|@option{--hex-dump=}<number or name>]
3690 [@option{-p} <number or name>|@option{--string-dump=}<number or name>]
3691 [@option{-c}|@option{--archive-index}]
3692 [@option{-w[liaprmfFsoR]}|
3693 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
3694 [@option{-I}|@option{-histogram}]
3695 [@option{-v}|@option{--version}]
3696 [@option{-W}|@option{--wide}]
3697 [@option{-H}|@option{--help}]
3698 @var{elffile}@dots{}
3699@c man end
3700@end smallexample
3701
3702@c man begin DESCRIPTION readelf
3703
3704@command{readelf} displays information about one or more ELF format object
3705files. The options control what particular information to display.
3706
3707@var{elffile}@dots{} are the object files to be examined. 32-bit and
370864-bit ELF files are supported, as are archives containing ELF files.
3709
3710This program performs a similar function to @command{objdump} but it
3711goes into more detail and it exists independently of the @sc{bfd}
3712library, so if there is a bug in @sc{bfd} then readelf will not be
3713affected.
3714
3715@c man end
3716
3717@c man begin OPTIONS readelf
3718
3719The long and short forms of options, shown here as alternatives, are
3720equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3721given.
3722
3723@table @env
3724@item -a
3725@itemx --all
3726Equivalent to specifying @option{--file-header},
3727@option{--program-headers}, @option{--sections}, @option{--symbols},
3728@option{--relocs}, @option{--dynamic}, @option{--notes} and
3729@option{--version-info}.
3730
3731@item -h
3732@itemx --file-header
3733@cindex ELF file header information
3734Displays the information contained in the ELF header at the start of the
3735file.
3736
3737@item -l
3738@itemx --program-headers
3739@itemx --segments
3740@cindex ELF program header information
3741@cindex ELF segment information
3742Displays the information contained in the file's segment headers, if it
3743has any.
3744
3745@item -S
3746@itemx --sections
3747@itemx --section-headers
3748@cindex ELF section information
3749Displays the information contained in the file's section headers, if it
3750has any.
3751
3752@item -g
3753@itemx --section-groups
3754@cindex ELF section group information
3755Displays the information contained in the file's section groups, if it
3756has any.
3757
3758@item -t
3759@itemx --section-details
3760@cindex ELF section information
3761Displays the detailed section information. Implies @option{-S}.
3762
3763@item -s
3764@itemx --symbols
3765@itemx --syms
3766@cindex ELF symbol table information
3767Displays the entries in symbol table section of the file, if it has one.
3768
3769@item -e
3770@itemx --headers
3771Display all the headers in the file. Equivalent to @option{-h -l -S}.
3772
3773@item -n
3774@itemx --notes
3775@cindex ELF notes
3776Displays the contents of the NOTE segments and/or sections, if any.
3777
3778@item -r
3779@itemx --relocs
3780@cindex ELF reloc information
3781Displays the contents of the file's relocation section, if it has one.
3782
3783@item -u
3784@itemx --unwind
3785@cindex unwind information
3786Displays the contents of the file's unwind section, if it has one. Only
3787the unwind sections for IA64 ELF files are currently supported.
3788
3789@item -d
3790@itemx --dynamic
3791@cindex ELF dynamic section information
3792Displays the contents of the file's dynamic section, if it has one.
3793
3794@item -V
3795@itemx --version-info
3796@cindex ELF version sections informations
3797Displays the contents of the version sections in the file, it they
3798exist.
3799
3800@item -A
3801@itemx --arch-specific
3802Displays architecture-specific information in the file, if there
3803is any.
3804
3805@item -D
3806@itemx --use-dynamic
3807When displaying symbols, this option makes @command{readelf} use the
3808symbol table in the file's dynamic section, rather than the one in the
3809symbols section.
3810
3811@item -x <number or name>
3812@itemx --hex-dump=<number or name>
3813Displays the contents of the indicated section as a hexadecimal dump.
3814A number identifies a particular section by index in the section table;
3815any other string identifies all sections with that name in the object file.
3816
3817@item -p <number or name>
3818@itemx --string-dump=<number or name>
3819Displays the contents of the indicated section as printable strings.
3820A number identifies a particular section by index in the section table;
3821any other string identifies all sections with that name in the object file.
3822
3823@item -c
3824@itemx --archive-index
3825@cindex Archive file symbol index information
3826Displays the file symbol index infomation contained in the header part
3827of binary archives. Performs the same function as the @option{t}
3828command to @command{ar}, but without using the BFD library. @xref{ar}.
3829
3830@item -w[liaprmfFsoR]
3831@itemx --debug-dump[=line,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]
3832Displays the contents of the debug sections in the file, if any are
3833present. If one of the optional letters or words follows the switch
3834then only data found in those specific sections will be dumped.
3835
3836@item -I
3837@itemx --histogram
3838Display a histogram of bucket list lengths when displaying the contents
3839of the symbol tables.
3840
3841@item -v
3842@itemx --version
3843Display the version number of readelf.
3844
3845@item -W
3846@itemx --wide
3847Don't break output lines to fit into 80 columns. By default
3848@command{readelf} breaks section header and segment listing lines for
384964-bit ELF files, so that they fit into 80 columns. This option causes
3850@command{readelf} to print each section header resp. each segment one a
3851single line, which is far more readable on terminals wider than 80 columns.
3852
3853@item -H
3854@itemx --help
3855Display the command line options understood by @command{readelf}.
3856
3857@end table
3858
3859@c man end
3860
3861@ignore
3862@c man begin SEEALSO readelf
3863objdump(1), and the Info entries for @file{binutils}.
3864@c man end
3865@end ignore
3866
3867@node Common Options
3868@chapter Common Options
3869
3870The following command-line options are supported by all of the
3871programs described in this manual.
3872
3873@c man begin OPTIONS
3874@table @env
3875@include at-file.texi
3876@c man end
3877
3878@item --help
3879Display the command-line options supported by the program.
3880
3881@item --version
3882Display the version number of the program.
3883
3884@c man begin OPTIONS
3885@end table
3886@c man end
3887
3888@node Selecting The Target System
3889@chapter Selecting the Target System
3890
3891You can specify two aspects of the target system to the @sc{gnu}
3892binary file utilities, each in several ways:
3893
3894@itemize @bullet
3895@item
3896the target
3897
3898@item
3899the architecture
3900@end itemize
3901
3902In the following summaries, the lists of ways to specify values are in
3903order of decreasing precedence. The ways listed first override those
3904listed later.
3905
3906The commands to list valid values only list the values for which the
3907programs you are running were configured. If they were configured with
3908@option{--enable-targets=all}, the commands list most of the available
3909values, but a few are left out; not all targets can be configured in at
3910once because some of them can only be configured @dfn{native} (on hosts
3911with the same type as the target system).
3912
3913@menu
3914* Target Selection::
3915* Architecture Selection::
3916@end menu
3917
3918@node Target Selection
3919@section Target Selection
3920
3921A @dfn{target} is an object file format. A given target may be
3922supported for multiple architectures (@pxref{Architecture Selection}).
3923A target selection may also have variations for different operating
3924systems or architectures.
3925
3926The command to list valid target values is @samp{objdump -i}
3927(the first column of output contains the relevant information).
3928
3929Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3930@samp{a.out-sunos-big}.
3931
3932You can also specify a target using a configuration triplet. This is
3933the same sort of name that is passed to @file{configure} to specify a
3934target. When you use a configuration triplet as an argument, it must be
3935fully canonicalized. You can see the canonical version of a triplet by
3936running the shell script @file{config.sub} which is included with the
3937sources.
3938
3939Some sample configuration triplets are: @samp{m68k-hp-bsd},
3940@samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3941
3942@subheading @command{objdump} Target
3943
3944Ways to specify:
3945
3946@enumerate
3947@item
3948command line option: @option{-b} or @option{--target}
3949
3950@item
3951environment variable @code{GNUTARGET}
3952
3953@item
3954deduced from the input file
3955@end enumerate
3956
3957@subheading @command{objcopy} and @command{strip} Input Target
3958
3959Ways to specify:
3960
3961@enumerate
3962@item
3963command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3964
3965@item
3966environment variable @code{GNUTARGET}
3967
3968@item
3969deduced from the input file
3970@end enumerate
3971
3972@subheading @command{objcopy} and @command{strip} Output Target
3973
3974Ways to specify:
3975
3976@enumerate
3977@item
3978command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3979
3980@item
3981the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3982
3983@item
3984environment variable @code{GNUTARGET}
3985
3986@item
3987deduced from the input file
3988@end enumerate
3989
3990@subheading @command{nm}, @command{size}, and @command{strings} Target
3991
3992Ways to specify:
3993
3994@enumerate
3995@item
3996command line option: @option{--target}
3997
3998@item
3999environment variable @code{GNUTARGET}
4000
4001@item
4002deduced from the input file
4003@end enumerate
4004
4005@node Architecture Selection
4006@section Architecture Selection
4007
4008An @dfn{architecture} is a type of @sc{cpu} on which an object file is
4009to run. Its name may contain a colon, separating the name of the
4010processor family from the name of the particular @sc{cpu}.
4011
4012The command to list valid architecture values is @samp{objdump -i} (the
4013second column contains the relevant information).
4014
4015Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
4016
4017@subheading @command{objdump} Architecture
4018
4019Ways to specify:
4020
4021@enumerate
4022@item
4023command line option: @option{-m} or @option{--architecture}
4024
4025@item
4026deduced from the input file
4027@end enumerate
4028
4029@subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
4030
4031Ways to specify:
4032
4033@enumerate
4034@item
4035deduced from the input file
4036@end enumerate
4037
4038@node Reporting Bugs
4039@chapter Reporting Bugs
4040@cindex bugs
4041@cindex reporting bugs
4042
4043Your bug reports play an essential role in making the binary utilities
4044reliable.
4045
4046Reporting a bug may help you by bringing a solution to your problem, or
4047it may not. But in any case the principal function of a bug report is
4048to help the entire community by making the next version of the binary
4049utilities work better. Bug reports are your contribution to their
4050maintenance.
4051
4052In order for a bug report to serve its purpose, you must include the
4053information that enables us to fix the bug.
4054
4055@menu
4056* Bug Criteria:: Have you found a bug?
4057* Bug Reporting:: How to report bugs
4058@end menu
4059
4060@node Bug Criteria
4061@section Have You Found a Bug?
4062@cindex bug criteria
4063
4064If you are not sure whether you have found a bug, here are some guidelines:
4065
4066@itemize @bullet
4067@cindex fatal signal
4068@cindex crash
4069@item
4070If a binary utility gets a fatal signal, for any input whatever, that is
4071a bug. Reliable utilities never crash.
4072
4073@cindex error on valid input
4074@item
4075If a binary utility produces an error message for valid input, that is a
4076bug.
4077
4078@item
4079If you are an experienced user of binary utilities, your suggestions for
4080improvement are welcome in any case.
4081@end itemize
4082
4083@node Bug Reporting
4084@section How to Report Bugs
4085@cindex bug reports
4086@cindex bugs, reporting
4087
4088A number of companies and individuals offer support for @sc{gnu}
4089products. If you obtained the binary utilities from a support
4090organization, we recommend you contact that organization first.
4091
4092You can find contact information for many support companies and
4093individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
4094distribution.
4095
4096@ifset BUGURL
4097In any event, we also recommend that you send bug reports for the binary
4098utilities to @value{BUGURL}.
4099@end ifset
4100
4101The fundamental principle of reporting bugs usefully is this:
4102@strong{report all the facts}. If you are not sure whether to state a
4103fact or leave it out, state it!
4104
4105Often people omit facts because they think they know what causes the
4106problem and assume that some details do not matter. Thus, you might
4107assume that the name of a file you use in an example does not matter.
4108Well, probably it does not, but one cannot be sure. Perhaps the bug is
4109a stray memory reference which happens to fetch from the location where
4110that pathname is stored in memory; perhaps, if the pathname were
4111different, the contents of that location would fool the utility into
4112doing the right thing despite the bug. Play it safe and give a
4113specific, complete example. That is the easiest thing for you to do,
4114and the most helpful.
4115
4116Keep in mind that the purpose of a bug report is to enable us to fix the bug if
4117it is new to us. Therefore, always write your bug reports on the assumption
4118that the bug has not been reported previously.
4119
4120Sometimes people give a few sketchy facts and ask, ``Does this ring a
4121bell?'' This cannot help us fix a bug, so it is basically useless. We
4122respond by asking for enough details to enable us to investigate.
4123You might as well expedite matters by sending them to begin with.
4124
4125To enable us to fix the bug, you should include all these things:
4126
4127@itemize @bullet
4128@item
4129The version of the utility. Each utility announces it if you start it
4130with the @option{--version} argument.
4131
4132Without this, we will not know whether there is any point in looking for
4133the bug in the current version of the binary utilities.
4134
4135@item
4136Any patches you may have applied to the source, including any patches
4137made to the @code{BFD} library.
4138
4139@item
4140The type of machine you are using, and the operating system name and
4141version number.
4142
4143@item
4144What compiler (and its version) was used to compile the utilities---e.g.
4145``@code{gcc-2.7}''.
4146
4147@item
4148The command arguments you gave the utility to observe the bug. To
4149guarantee you will not omit something important, list them all. A copy
4150of the Makefile (or the output from make) is sufficient.
4151
4152If we were to try to guess the arguments, we would probably guess wrong
4153and then we might not encounter the bug.
4154
4155@item
4156A complete input file, or set of input files, that will reproduce the
4157bug. If the utility is reading an object file or files, then it is
4158generally most helpful to send the actual object files.
4159
4160If the source files were produced exclusively using @sc{gnu} programs
4161(e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
4162may be OK to send the source files rather than the object files. In
4163this case, be sure to say exactly what version of @command{gcc}, or
4164whatever, was used to produce the object files. Also say how
4165@command{gcc}, or whatever, was configured.
4166
4167@item
4168A description of what behavior you observe that you believe is
4169incorrect. For example, ``It gets a fatal signal.''
4170
4171Of course, if the bug is that the utility gets a fatal signal, then we
4172will certainly notice it. But if the bug is incorrect output, we might
4173not notice unless it is glaringly wrong. You might as well not give us
4174a chance to make a mistake.
4175
4176Even if the problem you experience is a fatal signal, you should still
4177say so explicitly. Suppose something strange is going on, such as your
4178copy of the utility is out of sync, or you have encountered a bug in
4179the C library on your system. (This has happened!) Your copy might
4180crash and ours would not. If you told us to expect a crash, then when
4181ours fails to crash, we would know that the bug was not happening for
4182us. If you had not told us to expect a crash, then we would not be able
4183to draw any conclusion from our observations.
4184
4185@item
4186If you wish to suggest changes to the source, send us context diffs, as
4187generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
4188option. Always send diffs from the old file to the new file. If you
4189wish to discuss something in the @command{ld} source, refer to it by
4190context, not by line number.
4191
4192The line numbers in our development sources will not match those in your
4193sources. Your line numbers would convey no useful information to us.
4194@end itemize
4195
4196Here are some things that are not necessary:
4197
4198@itemize @bullet
4199@item
4200A description of the envelope of the bug.
4201
4202Often people who encounter a bug spend a lot of time investigating
4203which changes to the input file will make the bug go away and which
4204changes will not affect it.
4205
4206This is often time consuming and not very useful, because the way we
4207will find the bug is by running a single example under the debugger
4208with breakpoints, not by pure deduction from a series of examples.
4209We recommend that you save your time for something else.
4210
4211Of course, if you can find a simpler example to report @emph{instead}
4212of the original one, that is a convenience for us. Errors in the
4213output will be easier to spot, running under the debugger will take
4214less time, and so on.
4215
4216However, simplification is not vital; if you do not want to do this,
4217report the bug anyway and send us the entire test case you used.
4218
4219@item
4220A patch for the bug.
4221
4222A patch for the bug does help us if it is a good one. But do not omit
4223the necessary information, such as the test case, on the assumption that
4224a patch is all we need. We might see problems with your patch and decide
4225to fix the problem another way, or we might not understand it at all.
4226
4227Sometimes with programs as complicated as the binary utilities it is
4228very hard to construct an example that will make the program follow a
4229certain path through the code. If you do not send us the example, we
4230will not be able to construct one, so we will not be able to verify that
4231the bug is fixed.
4232
4233And if we cannot understand what bug you are trying to fix, or why your
4234patch should be an improvement, we will not install it. A test case will
4235help us to understand.
4236
4237@item
4238A guess about what the bug is or what it depends on.
4239
4240Such guesses are usually wrong. Even we cannot guess right about such
4241things without first using the debugger to find the facts.
4242@end itemize
4243
4244@include fdl.texi
4245
4246@node Binutils Index
4247@unnumbered Binutils Index
4248
4249@printindex cp
4250
4251@bye
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