1OBJDUMP(1)                   GNU Development Tools                  OBJDUMP(1)
2
3
4

NAME

6       objdump - display information from object files.
7

SYNOPSIS

9       objdump [-a|--archive-headers]
10               [-b bfdname|--target=bfdname]
11               [-C|--demangle[=style] ]
12               [-d|--disassemble]
13               [-D|--disassemble-all]
14               [-z|--disassemble-zeroes]
15               [-EB|-EL|--endian={big | little }]
16               [-f|--file-headers]
17               [-F|--file-offsets]
18               [--file-start-context]
19               [-g|--debugging]
20               [-e|--debugging-tags]
21               [-h|--section-headers|--headers]
22               [-i|--info]
23               [-j section|--section=section]
24               [-l|--line-numbers]
25               [-S|--source]
26               [-m machine|--architecture=machine]
27               [-M options|--disassembler-options=options]
28               [-p|--private-headers]
29               [-P options|--private=options]
30               [-r|--reloc]
31               [-R|--dynamic-reloc]
32               [-s|--full-contents]
33               [-W[lLiaprmfFsoRt]|
34                --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
35                        [=aranges,=macro,=frames,=frames-interp,=str,=loc]
36                        [=Ranges,=pubtypes,=trace_info,=trace_abbrev]
37                        [=trace_aranges,=gdb_index]
38               [-G|--stabs]
39               [-t|--syms]
40               [-T|--dynamic-syms]
41               [-x|--all-headers]
42               [-w|--wide]
43               [--start-address=address]
44               [--stop-address=address]
45               [--prefix-addresses]
46               [--[no-]show-raw-insn]
47               [--adjust-vma=offset]
48               [--special-syms]
49               [--prefix=prefix]
50               [--prefix-strip=level]
51               [--insn-width=width]
52               [-V|--version]
53               [-H|--help]
54               objfile...
55

DESCRIPTION

57       objdump displays information about one or more object files.  The
58       options control what particular information to display.  This
59       information is mostly useful to programmers who are working on the
60       compilation tools, as opposed to programmers who just want their
61       program to compile and work.
62
63       objfile... are the object files to be examined.  When you specify
64       archives, objdump shows information on each of the member object files.
65

OPTIONS

67       The long and short forms of options, shown here as alternatives, are
68       equivalent.  At least one option from the list
69       -a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x must be given.
70
71       -a
72       --archive-header
73           If any of the objfile files are archives, display the archive
74           header information (in a format similar to ls -l).  Besides the
75           information you could list with ar tv, objdump -a shows the object
76           file format of each archive member.
77
78       --adjust-vma=offset
79           When dumping information, first add offset to all the section
80           addresses.  This is useful if the section addresses do not
81           correspond to the symbol table, which can happen when putting
82           sections at particular addresses when using a format which can not
83           represent section addresses, such as a.out.
84
85       -b bfdname
86       --target=bfdname
87           Specify that the object-code format for the object files is
88           bfdname.  This option may not be necessary; objdump can
89           automatically recognize many formats.
90
91           For example,
92
93                   objdump -b oasys -m vax -h fu.o
94
95           displays summary information from the section headers (-h) of fu.o,
96           which is explicitly identified (-m) as a VAX object file in the
97           format produced by Oasys compilers.  You can list the formats
98           available with the -i option.
99
100       -C
101       --demangle[=style]
102           Decode (demangle) low-level symbol names into user-level names.
103           Besides removing any initial underscore prepended by the system,
104           this makes C++ function names readable.  Different compilers have
105           different mangling styles. The optional demangling style argument
106           can be used to choose an appropriate demangling style for your
107           compiler.
108
109       -g
110       --debugging
111           Display debugging information.  This attempts to parse STABS and
112           IEEE debugging format information stored in the file and print it
113           out using a C like syntax.  If neither of these formats are found
114           this option falls back on the -W option to print any DWARF
115           information in the file.
116
117       -e
118       --debugging-tags
119           Like -g, but the information is generated in a format compatible
120           with ctags tool.
121
122       -d
123       --disassemble
124           Display the assembler mnemonics for the machine instructions from
125           objfile.  This option only disassembles those sections which are
126           expected to contain instructions.
127
128       -D
129       --disassemble-all
130           Like -d, but disassemble the contents of all sections, not just
131           those expected to contain instructions.
132
133           This option also has a subtle effect on the disassembly of
134           instructions in code sections.  When option -d is in effect objdump
135           will assume that any symbols present in a code section occur on the
136           boundary between instructions and it will refuse to disassemble
137           across such a boundary.  When option -D is in effect however this
138           assumption is supressed.  This means that it is possible for the
139           output of -d and -D to differ if, for example, data is stored in
140           code sections.
141
142           If the target is an ARM architecture this switch also has the
143           effect of forcing the disassembler to decode pieces of data found
144           in code sections as if they were instructions.
145
146       --prefix-addresses
147           When disassembling, print the complete address on each line.  This
148           is the older disassembly format.
149
150       -EB
151       -EL
152       --endian={big|little}
153           Specify the endianness of the object files.  This only affects
154           disassembly.  This can be useful when disassembling a file format
155           which does not describe endianness information, such as S-records.
156
157       -f
158       --file-headers
159           Display summary information from the overall header of each of the
160           objfile files.
161
162       -F
163       --file-offsets
164           When disassembling sections, whenever a symbol is displayed, also
165           display the file offset of the region of data that is about to be
166           dumped.  If zeroes are being skipped, then when disassembly
167           resumes, tell the user how many zeroes were skipped and the file
168           offset of the location from where the disassembly resumes.  When
169           dumping sections, display the file offset of the location from
170           where the dump starts.
171
172       --file-start-context
173           Specify that when displaying interlisted source code/disassembly
174           (assumes -S) from a file that has not yet been displayed, extend
175           the context to the start of the file.
176
177       -h
178       --section-headers
179       --headers
180           Display summary information from the section headers of the object
181           file.
182
183           File segments may be relocated to nonstandard addresses, for
184           example by using the -Ttext, -Tdata, or -Tbss options to ld.
185           However, some object file formats, such as a.out, do not store the
186           starting address of the file segments.  In those situations,
187           although ld relocates the sections correctly, using objdump -h to
188           list the file section headers cannot show the correct addresses.
189           Instead, it shows the usual addresses, which are implicit for the
190           target.
191
192       -H
193       --help
194           Print a summary of the options to objdump and exit.
195
196       -i
197       --info
198           Display a list showing all architectures and object formats
199           available for specification with -b or -m.
200
201       -j name
202       --section=name
203           Display information only for section name.
204
205       -l
206       --line-numbers
207           Label the display (using debugging information) with the filename
208           and source line numbers corresponding to the object code or relocs
209           shown.  Only useful with -d, -D, or -r.
210
211       -m machine
212       --architecture=machine
213           Specify the architecture to use when disassembling object files.
214           This can be useful when disassembling object files which do not
215           describe architecture information, such as S-records.  You can list
216           the available architectures with the -i option.
217
218           If the target is an ARM architecture then this switch has an
219           additional effect.  It restricts the disassembly to only those
220           instructions supported by the architecture specified by machine.
221           If it is necessary to use this switch because the input file does
222           not contain any architecture information, but it is also desired to
223           disassemble all the instructions use -marm.
224
225       -M options
226       --disassembler-options=options
227           Pass target specific information to the disassembler.  Only
228           supported on some targets.  If it is necessary to specify more than
229           one disassembler option then multiple -M options can be used or can
230           be placed together into a comma separated list.
231
232           If the target is an ARM architecture then this switch can be used
233           to select which register name set is used during disassembler.
234           Specifying -M reg-names-std (the default) will select the register
235           names as used in ARM's instruction set documentation, but with
236           register 13 called 'sp', register 14 called 'lr' and register 15
237           called 'pc'.  Specifying -M reg-names-apcs will select the name set
238           used by the ARM Procedure Call Standard, whilst specifying -M reg-
239           names-raw will just use r followed by the register number.
240
241           There are also two variants on the APCS register naming scheme
242           enabled by -M reg-names-atpcs and -M reg-names-special-atpcs which
243           use the ARM/Thumb Procedure Call Standard naming conventions.
244           (Either with the normal register names or the special register
245           names).
246
247           This option can also be used for ARM architectures to force the
248           disassembler to interpret all instructions as Thumb instructions by
249           using the switch --disassembler-options=force-thumb.  This can be
250           useful when attempting to disassemble thumb code produced by other
251           compilers.
252
253           For the x86, some of the options duplicate functions of the -m
254           switch, but allow finer grained control.  Multiple selections from
255           the following may be specified as a comma separated string.
256
257           "x86-64"
258           "i386"
259           "i8086"
260               Select disassembly for the given architecture.
261
262           "intel"
263           "att"
264               Select between intel syntax mode and AT&T syntax mode.
265
266           "amd64"
267           "intel64"
268               Select between AMD64 ISA and Intel64 ISA.
269
270           "intel-mnemonic"
271           "att-mnemonic"
272               Select between intel mnemonic mode and AT&T mnemonic mode.
273               Note: "intel-mnemonic" implies "intel" and "att-mnemonic"
274               implies "att".
275
276           "addr64"
277           "addr32"
278           "addr16"
279           "data32"
280           "data16"
281               Specify the default address size and operand size.  These four
282               options will be overridden if "x86-64", "i386" or "i8086"
283               appear later in the option string.
284
285           "suffix"
286               When in AT&T mode, instructs the disassembler to print a
287               mnemonic suffix even when the suffix could be inferred by the
288               operands.
289
290           For PowerPC, booke controls the disassembly of BookE instructions.
291           32 and 64 select PowerPC and PowerPC64 disassembly, respectively.
292           e300 selects disassembly for the e300 family.  440 selects
293           disassembly for the PowerPC 440.  ppcps selects disassembly for the
294           paired single instructions of the PPC750CL.
295
296           For MIPS, this option controls the printing of instruction mnemonic
297           names and register names in disassembled instructions.  Multiple
298           selections from the following may be specified as a comma separated
299           string, and invalid options are ignored:
300
301           "no-aliases"
302               Print the 'raw' instruction mnemonic instead of some pseudo
303               instruction mnemonic.  I.e., print 'daddu' or 'or' instead of
304               'move', 'sll' instead of 'nop', etc.
305
306           "msa"
307               Disassemble MSA instructions.
308
309           "virt"
310               Disassemble the virtualization ASE instructions.
311
312           "xpa"
313               Disassemble the eXtended Physical Address (XPA) ASE
314               instructions.
315
316           "gpr-names=ABI"
317               Print GPR (general-purpose register) names as appropriate for
318               the specified ABI.  By default, GPR names are selected
319               according to the ABI of the binary being disassembled.
320
321           "fpr-names=ABI"
322               Print FPR (floating-point register) names as appropriate for
323               the specified ABI.  By default, FPR numbers are printed rather
324               than names.
325
326           "cp0-names=ARCH"
327               Print CP0 (system control coprocessor; coprocessor 0) register
328               names as appropriate for the CPU or architecture specified by
329               ARCH.  By default, CP0 register names are selected according to
330               the architecture and CPU of the binary being disassembled.
331
332           "hwr-names=ARCH"
333               Print HWR (hardware register, used by the "rdhwr" instruction)
334               names as appropriate for the CPU or architecture specified by
335               ARCH.  By default, HWR names are selected according to the
336               architecture and CPU of the binary being disassembled.
337
338           "reg-names=ABI"
339               Print GPR and FPR names as appropriate for the selected ABI.
340
341           "reg-names=ARCH"
342               Print CPU-specific register names (CP0 register and HWR names)
343               as appropriate for the selected CPU or architecture.
344
345           For any of the options listed above, ABI or ARCH may be specified
346           as numeric to have numbers printed rather than names, for the
347           selected types of registers.  You can list the available values of
348           ABI and ARCH using the --help option.
349
350           For VAX, you can specify function entry addresses with -M
351           entry:0xf00ba.  You can use this multiple times to properly
352           disassemble VAX binary files that don't contain symbol tables (like
353           ROM dumps).  In these cases, the function entry mask would
354           otherwise be decoded as VAX instructions, which would probably lead
355           the rest of the function being wrongly disassembled.
356
357       -p
358       --private-headers
359           Print information that is specific to the object file format.  The
360           exact information printed depends upon the object file format.  For
361           some object file formats, no additional information is printed.
362
363       -P options
364       --private=options
365           Print information that is specific to the object file format.  The
366           argument options is a comma separated list that depends on the
367           format (the lists of options is displayed with the help).
368
369           For XCOFF, the available options are:
370
371           "header"
372           "aout"
373           "sections"
374           "syms"
375           "relocs"
376           "lineno,"
377           "loader"
378           "except"
379           "typchk"
380           "traceback"
381           "toc"
382           "ldinfo"
383
384           Not all object formats support this option.  In particular the ELF
385           format does not use it.
386
387       -r
388       --reloc
389           Print the relocation entries of the file.  If used with -d or -D,
390           the relocations are printed interspersed with the disassembly.
391
392       -R
393       --dynamic-reloc
394           Print the dynamic relocation entries of the file.  This is only
395           meaningful for dynamic objects, such as certain types of shared
396           libraries.  As for -r, if used with -d or -D, the relocations are
397           printed interspersed with the disassembly.
398
399       -s
400       --full-contents
401           Display the full contents of any sections requested.  By default
402           all non-empty sections are displayed.
403
404       -S
405       --source
406           Display source code intermixed with disassembly, if possible.
407           Implies -d.
408
409       --prefix=prefix
410           Specify prefix to add to the absolute paths when used with -S.
411
412       --prefix-strip=level
413           Indicate how many initial directory names to strip off the
414           hardwired absolute paths. It has no effect without --prefix=prefix.
415
416       --show-raw-insn
417           When disassembling instructions, print the instruction in hex as
418           well as in symbolic form.  This is the default except when
419           --prefix-addresses is used.
420
421       --no-show-raw-insn
422           When disassembling instructions, do not print the instruction
423           bytes.  This is the default when --prefix-addresses is used.
424
425       --insn-width=width
426           Display width bytes on a single line when disassembling
427           instructions.
428
429       -W[lLiaprmfFsoRt]
430       --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
431       --dwarf[=aranges,=macro,=frames,=frames-interp,=str,=loc]
432       --dwarf[=Ranges,=pubtypes,=trace_info,=trace_abbrev]
433       --dwarf[=trace_aranges,=gdb_index]
434           Displays the contents of the debug sections in the file, if any are
435           present.  If one of the optional letters or words follows the
436           switch then only data found in those specific sections will be
437           dumped.
438
439           Note that there is no single letter option to display the content
440           of trace sections or .gdb_index.
441
442           Note: the output from the =info option can also be affected by the
443           options --dwarf-depth, the --dwarf-start and the --dwarf-check.
444
445       --dwarf-depth=n
446           Limit the dump of the ".debug_info" section to n children.  This is
447           only useful with --dwarf=info.  The default is to print all DIEs;
448           the special value 0 for n will also have this effect.
449
450           With a non-zero value for n, DIEs at or deeper than n levels will
451           not be printed.  The range for n is zero-based.
452
453       --dwarf-start=n
454           Print only DIEs beginning with the DIE numbered n.  This is only
455           useful with --dwarf=info.
456
457           If specified, this option will suppress printing of any header
458           information and all DIEs before the DIE numbered n.  Only siblings
459           and children of the specified DIE will be printed.
460
461           This can be used in conjunction with --dwarf-depth.
462
463       --dwarf-check
464           Enable additional checks for consistency of Dwarf information.
465
466       -G
467       --stabs
468           Display the full contents of any sections requested.  Display the
469           contents of the .stab and .stab.index and .stab.excl sections from
470           an ELF file.  This is only useful on systems (such as Solaris 2.0)
471           in which ".stab" debugging symbol-table entries are carried in an
472           ELF section.  In most other file formats, debugging symbol-table
473           entries are interleaved with linkage symbols, and are visible in
474           the --syms output.
475
476       --start-address=address
477           Start displaying data at the specified address.  This affects the
478           output of the -d, -r and -s options.
479
480       --stop-address=address
481           Stop displaying data at the specified address.  This affects the
482           output of the -d, -r and -s options.
483
484       -t
485       --syms
486           Print the symbol table entries of the file.  This is similar to the
487           information provided by the nm program, although the display format
488           is different.  The format of the output depends upon the format of
489           the file being dumped, but there are two main types.  One looks
490           like this:
491
492                   [  4](sec  3)(fl 0x00)(ty   0)(scl   3) (nx 1) 0x00000000 .bss
493                   [  6](sec  1)(fl 0x00)(ty   0)(scl   2) (nx 0) 0x00000000 fred
494
495           where the number inside the square brackets is the number of the
496           entry in the symbol table, the sec number is the section number,
497           the fl value are the symbol's flag bits, the ty number is the
498           symbol's type, the scl number is the symbol's storage class and the
499           nx value is the number of auxilary entries associated with the
500           symbol.  The last two fields are the symbol's value and its name.
501
502           The other common output format, usually seen with ELF based files,
503           looks like this:
504
505                   00000000 l    d  .bss   00000000 .bss
506                   00000000 g       .text  00000000 fred
507
508           Here the first number is the symbol's value (sometimes refered to
509           as its address).  The next field is actually a set of characters
510           and spaces indicating the flag bits that are set on the symbol.
511           These characters are described below.  Next is the section with
512           which the symbol is associated or *ABS* if the section is absolute
513           (ie not connected with any section), or *UND* if the section is
514           referenced in the file being dumped, but not defined there.
515
516           After the section name comes another field, a number, which for
517           common symbols is the alignment and for other symbol is the size.
518           Finally the symbol's name is displayed.
519
520           The flag characters are divided into 7 groups as follows:
521
522           "l"
523           "g"
524           "u"
525           "!" The symbol is a local (l), global (g), unique global (u),
526               neither global nor local (a space) or both global and local
527               (!).  A symbol can be neither local or global for a variety of
528               reasons, e.g., because it is used for debugging, but it is
529               probably an indication of a bug if it is ever both local and
530               global.  Unique global symbols are a GNU extension to the
531               standard set of ELF symbol bindings.  For such a symbol the
532               dynamic linker will make sure that in the entire process there
533               is just one symbol with this name and type in use.
534
535           "w" The symbol is weak (w) or strong (a space).
536
537           "C" The symbol denotes a constructor (C) or an ordinary symbol (a
538               space).
539
540           "W" The symbol is a warning (W) or a normal symbol (a space).  A
541               warning symbol's name is a message to be displayed if the
542               symbol following the warning symbol is ever referenced.
543
544           "I"
545           "i" The symbol is an indirect reference to another symbol (I), a
546               function to be evaluated during reloc processing (i) or a
547               normal symbol (a space).
548
549           "d"
550           "D" The symbol is a debugging symbol (d) or a dynamic symbol (D) or
551               a normal symbol (a space).
552
553           "F"
554           "f"
555           "O" The symbol is the name of a function (F) or a file (f) or an
556               object (O) or just a normal symbol (a space).
557
558       -T
559       --dynamic-syms
560           Print the dynamic symbol table entries of the file.  This is only
561           meaningful for dynamic objects, such as certain types of shared
562           libraries.  This is similar to the information provided by the nm
563           program when given the -D (--dynamic) option.
564
565       --special-syms
566           When displaying symbols include those which the target considers to
567           be special in some way and which would not normally be of interest
568           to the user.
569
570       -V
571       --version
572           Print the version number of objdump and exit.
573
574       -x
575       --all-headers
576           Display all available header information, including the symbol
577           table and relocation entries.  Using -x is equivalent to specifying
578           all of -a -f -h -p -r -t.
579
580       -w
581       --wide
582           Format some lines for output devices that have more than 80
583           columns.  Also do not truncate symbol names when they are
584           displayed.
585
586       -z
587       --disassemble-zeroes
588           Normally the disassembly output will skip blocks of zeroes.  This
589           option directs the disassembler to disassemble those blocks, just
590           like any other data.
591
592       @file
593           Read command-line options from file.  The options read are inserted
594           in place of the original @file option.  If file does not exist, or
595           cannot be read, then the option will be treated literally, and not
596           removed.
597
598           Options in file are separated by whitespace.  A whitespace
599           character may be included in an option by surrounding the entire
600           option in either single or double quotes.  Any character (including
601           a backslash) may be included by prefixing the character to be
602           included with a backslash.  The file may itself contain additional
603           @file options; any such options will be processed recursively.
604

SEE ALSO

606       nm(1), readelf(1), and the Info entries for binutils.
607
609       Copyright (c) 1991-2015 Free Software Foundation, Inc.
610
611       Permission is granted to copy, distribute and/or modify this document
612       under the terms of the GNU Free Documentation License, Version 1.3 or
613       any later version published by the Free Software Foundation; with no
614       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
615       Texts.  A copy of the license is included in the section entitled "GNU
616       Free Documentation License".
617
618
619
620binutils-2.26                     2016-01-25                        OBJDUMP(1)
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