1OBJDUMP(1) GNU Development Tools OBJDUMP(1)
2
6 objdump - display information from object files.
7
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 [--dwarf-depth=n]
49 [--dwarf-start=n]
50 [--special-syms]
51 [--prefix=prefix]
52 [--prefix-strip=level]
53 [--insn-width=width]
54 [-V|--version]
55 [-H|--help]
56 objfile...
57
59 objdump displays information about one or more object files. The
60 options control what particular information to display. This
61 information is mostly useful to programmers who are working on the
62 compilation tools, as opposed to programmers who just want their
63 program to compile and work.
64 objfile... are the object files to be examined. When you specify
66 archives, objdump shows information on each of the member object files.
67
69 The long and short forms of options, shown here as alternatives, are
70 equivalent. At least one option from the list
71 -a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x must be given.
72 -a
74 --archive-header
75 If any of the objfile files are archives, display the archive
76 header information (in a format similar to ls -l). Besides the
77 information you could list with ar tv, objdump -a shows the object
78 file format of each archive member.
79 --adjust-vma=offset
81 When dumping information, first add offset to all the section
82 addresses. This is useful if the section addresses do not
83 correspond to the symbol table, which can happen when putting
84 sections at particular addresses when using a format which can not
85 represent section addresses, such as a.out.
86 -b bfdname
88 --target=bfdname
89 Specify that the object-code format for the object files is
90 bfdname. This option may not be necessary; objdump can
91 automatically recognize many formats.
92 For example,
94 objdump -b oasys -m vax -h fu.o
96 displays summary information from the section headers (-h) of fu.o,
98 which is explicitly identified (-m) as a VAX object file in the
99 format produced by Oasys compilers. You can list the formats
100 available with the -i option.
101 -C
103 --demangle[=style]
104 Decode (demangle) low-level symbol names into user-level names.
105 Besides removing any initial underscore prepended by the system,
106 this makes C++ function names readable. Different compilers have
107 different mangling styles. The optional demangling style argument
108 can be used to choose an appropriate demangling style for your
109 compiler.
110 -g
112 --debugging
113 Display debugging information. This attempts to parse STABS and
114 IEEE debugging format information stored in the file and print it
115 out using a C like syntax. If neither of these formats are found
116 this option falls back on the -W option to print any DWARF
117 information in the file.
118 -e
120 --debugging-tags
121 Like -g, but the information is generated in a format compatible
122 with ctags tool.
123 -d
125 --disassemble
126 Display the assembler mnemonics for the machine instructions from
127 objfile. This option only disassembles those sections which are
128 expected to contain instructions.
129 -D
131 --disassemble-all
132 Like -d, but disassemble the contents of all sections, not just
133 those expected to contain instructions.
134 This option also has a subtle effect on the disassembly of
136 instructions in code sections. When option -d is in effect objdump
137 will assume that any symbols present in a code section occur on the
138 boundary between instructions and it will refuse to disassemble
139 across such a boundary. When option -D is in effect however this
140 assumption is supressed. This means that it is possible for the
141 output of -d and -D to differ if, for example, data is stored in
142 code sections.
143 If the target is an ARM architecture this switch also has the
145 effect of forcing the disassembler to decode pieces of data found
146 in code sections as if they were instructions.
147 --prefix-addresses
149 When disassembling, print the complete address on each line. This
150 is the older disassembly format.
151 -EB
153 -EL
154 --endian={big|little}
155 Specify the endianness of the object files. This only affects
156 disassembly. This can be useful when disassembling a file format
157 which does not describe endianness information, such as S-records.
158 -f
160 --file-headers
161 Display summary information from the overall header of each of the
162 objfile files.
163 -F
165 --file-offsets
166 When disassembling sections, whenever a symbol is displayed, also
167 display the file offset of the region of data that is about to be
168 dumped. If zeroes are being skipped, then when disassembly
169 resumes, tell the user how many zeroes were skipped and the file
170 offset of the location from where the disassembly resumes. When
171 dumping sections, display the file offset of the location from
172 where the dump starts.
173 --file-start-context
175 Specify that when displaying interlisted source code/disassembly
176 (assumes -S) from a file that has not yet been displayed, extend
177 the context to the start of the file.
178 -h
180 --section-headers
181 --headers
182 Display summary information from the section headers of the object
183 file.
184 File segments may be relocated to nonstandard addresses, for
186 example by using the -Ttext, -Tdata, or -Tbss options to ld.
187 However, some object file formats, such as a.out, do not store the
188 starting address of the file segments. In those situations,
189 although ld relocates the sections correctly, using objdump -h to
190 list the file section headers cannot show the correct addresses.
191 Instead, it shows the usual addresses, which are implicit for the
192 target.
193 Note, in some cases it is possible for a section to have both the
195 READONLY and the NOREAD attributes set. In such cases the NOREAD
196 attribute takes precedence, but objdump will report both since the
197 exact setting of the flag bits might be important.
198 -H
200 --help
201 Print a summary of the options to objdump and exit.
202 -i
204 --info
205 Display a list showing all architectures and object formats
206 available for specification with -b or -m.
207 -j name
209 --section=name
210 Display information only for section name.
211 -l
213 --line-numbers
214 Label the display (using debugging information) with the filename
215 and source line numbers corresponding to the object code or relocs
216 shown. Only useful with -d, -D, or -r.
217 -m machine
219 --architecture=machine
220 Specify the architecture to use when disassembling object files.
221 This can be useful when disassembling object files which do not
222 describe architecture information, such as S-records. You can list
223 the available architectures with the -i option.
224 If the target is an ARM architecture then this switch has an
226 additional effect. It restricts the disassembly to only those
227 instructions supported by the architecture specified by machine.
228 If it is necessary to use this switch because the input file does
229 not contain any architecture information, but it is also desired to
230 disassemble all the instructions use -marm.
231 -M options
233 --disassembler-options=options
234 Pass target specific information to the disassembler. Only
235 supported on some targets. If it is necessary to specify more than
236 one disassembler option then multiple -M options can be used or can
237 be placed together into a comma separated list.
238 If the target is an ARM architecture then this switch can be used
240 to select which register name set is used during disassembler.
241 Specifying -M reg-names-std (the default) will select the register
242 names as used in ARM's instruction set documentation, but with
243 register 13 called 'sp', register 14 called 'lr' and register 15
244 called 'pc'. Specifying -M reg-names-apcs will select the name set
245 used by the ARM Procedure Call Standard, whilst specifying -M reg-
246 names-raw will just use r followed by the register number.
247 There are also two variants on the APCS register naming scheme
249 enabled by -M reg-names-atpcs and -M reg-names-special-atpcs which
250 use the ARM/Thumb Procedure Call Standard naming conventions.
251 (Either with the normal register names or the special register
252 names).
253 This option can also be used for ARM architectures to force the
255 disassembler to interpret all instructions as Thumb instructions by
256 using the switch --disassembler-options=force-thumb. This can be
257 useful when attempting to disassemble thumb code produced by other
258 compilers.
259 For the x86, some of the options duplicate functions of the -m
261 switch, but allow finer grained control. Multiple selections from
262 the following may be specified as a comma separated string.
263 "x86-64"
265 "i386"
266 "i8086"
267 Select disassembly for the given architecture.
268 "intel"
270 "att"
271 Select between intel syntax mode and AT&T syntax mode.
272 "amd64"
274 "intel64"
275 Select between AMD64 ISA and Intel64 ISA.
276 "intel-mnemonic"
278 "att-mnemonic"
279 Select between intel mnemonic mode and AT&T mnemonic mode.
280 Note: "intel-mnemonic" implies "intel" and "att-mnemonic"
281 implies "att".
282 "addr64"
284 "addr32"
285 "addr16"
286 "data32"
287 "data16"
288 Specify the default address size and operand size. These four
289 options will be overridden if "x86-64", "i386" or "i8086"
290 appear later in the option string.
291 "suffix"
293 When in AT&T mode, instructs the disassembler to print a
294 mnemonic suffix even when the suffix could be inferred by the
295 operands.
296 For PowerPC, booke controls the disassembly of BookE instructions.
298 32 and 64 select PowerPC and PowerPC64 disassembly, respectively.
299 e300 selects disassembly for the e300 family. 440 selects
300 disassembly for the PowerPC 440. ppcps selects disassembly for the
301 paired single instructions of the PPC750CL.
302 For MIPS, this option controls the printing of instruction mnemonic
304 names and register names in disassembled instructions. Multiple
305 selections from the following may be specified as a comma separated
306 string, and invalid options are ignored:
307 "no-aliases"
309 Print the 'raw' instruction mnemonic instead of some pseudo
310 instruction mnemonic. I.e., print 'daddu' or 'or' instead of
311 'move', 'sll' instead of 'nop', etc.
312 "msa"
314 Disassemble MSA instructions.
315 "virt"
317 Disassemble the virtualization ASE instructions.
318 "xpa"
320 Disassemble the eXtended Physical Address (XPA) ASE
321 instructions.
322 "gpr-names=ABI"
324 Print GPR (general-purpose register) names as appropriate for
325 the specified ABI. By default, GPR names are selected
326 according to the ABI of the binary being disassembled.
327 "fpr-names=ABI"
329 Print FPR (floating-point register) names as appropriate for
330 the specified ABI. By default, FPR numbers are printed rather
331 than names.
332 "cp0-names=ARCH"
334 Print CP0 (system control coprocessor; coprocessor 0) register
335 names as appropriate for the CPU or architecture specified by
336 ARCH. By default, CP0 register names are selected according to
337 the architecture and CPU of the binary being disassembled.
338 "hwr-names=ARCH"
340 Print HWR (hardware register, used by the "rdhwr" instruction)
341 names as appropriate for the CPU or architecture specified by
342 ARCH. By default, HWR names are selected according to the
343 architecture and CPU of the binary being disassembled.
344 "reg-names=ABI"
346 Print GPR and FPR names as appropriate for the selected ABI.
347 "reg-names=ARCH"
349 Print CPU-specific register names (CP0 register and HWR names)
350 as appropriate for the selected CPU or architecture.
351 For any of the options listed above, ABI or ARCH may be specified
353 as numeric to have numbers printed rather than names, for the
354 selected types of registers. You can list the available values of
355 ABI and ARCH using the --help option.
356 For VAX, you can specify function entry addresses with -M
358 entry:0xf00ba. You can use this multiple times to properly
359 disassemble VAX binary files that don't contain symbol tables (like
360 ROM dumps). In these cases, the function entry mask would
361 otherwise be decoded as VAX instructions, which would probably lead
362 the rest of the function being wrongly disassembled.
363 -p
365 --private-headers
366 Print information that is specific to the object file format. The
367 exact information printed depends upon the object file format. For
368 some object file formats, no additional information is printed.
369 -P options
371 --private=options
372 Print information that is specific to the object file format. The
373 argument options is a comma separated list that depends on the
374 format (the lists of options is displayed with the help).
375 For XCOFF, the available options are:
377 "header"
379 "aout"
380 "sections"
381 "syms"
382 "relocs"
383 "lineno,"
384 "loader"
385 "except"
386 "typchk"
387 "traceback"
388 "toc"
389 "ldinfo"
390 Not all object formats support this option. In particular the ELF
392 format does not use it.
393 -r
395 --reloc
396 Print the relocation entries of the file. If used with -d or -D,
397 the relocations are printed interspersed with the disassembly.
398 -R
400 --dynamic-reloc
401 Print the dynamic relocation entries of the file. This is only
402 meaningful for dynamic objects, such as certain types of shared
403 libraries. As for -r, if used with -d or -D, the relocations are
404 printed interspersed with the disassembly.
405 -s
407 --full-contents
408 Display the full contents of any sections requested. By default
409 all non-empty sections are displayed.
410 -S
412 --source
413 Display source code intermixed with disassembly, if possible.
414 Implies -d.
415 --prefix=prefix
417 Specify prefix to add to the absolute paths when used with -S.
418 --prefix-strip=level
420 Indicate how many initial directory names to strip off the
421 hardwired absolute paths. It has no effect without --prefix=prefix.
422 --show-raw-insn
424 When disassembling instructions, print the instruction in hex as
425 well as in symbolic form. This is the default except when
426 --prefix-addresses is used.
427 --no-show-raw-insn
429 When disassembling instructions, do not print the instruction
430 bytes. This is the default when --prefix-addresses is used.
431 --insn-width=width
433 Display width bytes on a single line when disassembling
434 instructions.
435 -W[lLiaprmfFsoRt]
437 --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames]
438 --dwarf[=aranges,=macro,=frames,=frames-interp,=str,=loc]
439 --dwarf[=Ranges,=pubtypes,=trace_info,=trace_abbrev]
440 --dwarf[=trace_aranges,=gdb_index]
441 Displays the contents of the debug sections in the file, if any are
442 present. If one of the optional letters or words follows the
443 switch then only data found in those specific sections will be
444 dumped.
445 Note that there is no single letter option to display the content
447 of trace sections or .gdb_index.
448 Note: the output from the =info option can also be affected by the
450 options --dwarf-depth, the --dwarf-start and the --dwarf-check.
451 --dwarf-depth=n
453 Limit the dump of the ".debug_info" section to n children. This is
454 only useful with --dwarf=info. The default is to print all DIEs;
455 the special value 0 for n will also have this effect.
456 With a non-zero value for n, DIEs at or deeper than n levels will
458 not be printed. The range for n is zero-based.
459 --dwarf-start=n
461 Print only DIEs beginning with the DIE numbered n. This is only
462 useful with --dwarf=info.
463 If specified, this option will suppress printing of any header
465 information and all DIEs before the DIE numbered n. Only siblings
466 and children of the specified DIE will be printed.
467 This can be used in conjunction with --dwarf-depth.
469 --dwarf-check
471 Enable additional checks for consistency of Dwarf information.
472 -G
474 --stabs
475 Display the full contents of any sections requested. Display the
476 contents of the .stab and .stab.index and .stab.excl sections from
477 an ELF file. This is only useful on systems (such as Solaris 2.0)
478 in which ".stab" debugging symbol-table entries are carried in an
479 ELF section. In most other file formats, debugging symbol-table
480 entries are interleaved with linkage symbols, and are visible in
481 the --syms output.
482 --start-address=address
484 Start displaying data at the specified address. This affects the
485 output of the -d, -r and -s options.
486 --stop-address=address
488 Stop displaying data at the specified address. This affects the
489 output of the -d, -r and -s options.
490 -t
492 --syms
493 Print the symbol table entries of the file. This is similar to the
494 information provided by the nm program, although the display format
495 is different. The format of the output depends upon the format of
496 the file being dumped, but there are two main types. One looks
497 like this:
498 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
500 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
501 where the number inside the square brackets is the number of the
503 entry in the symbol table, the sec number is the section number,
504 the fl value are the symbol's flag bits, the ty number is the
505 symbol's type, the scl number is the symbol's storage class and the
506 nx value is the number of auxilary entries associated with the
507 symbol. The last two fields are the symbol's value and its name.
508 The other common output format, usually seen with ELF based files,
510 looks like this:
511 00000000 l d .bss 00000000 .bss
513 00000000 g .text 00000000 fred
514 Here the first number is the symbol's value (sometimes refered to
516 as its address). The next field is actually a set of characters
517 and spaces indicating the flag bits that are set on the symbol.
518 These characters are described below. Next is the section with
519 which the symbol is associated or *ABS* if the section is absolute
520 (ie not connected with any section), or *UND* if the section is
521 referenced in the file being dumped, but not defined there.
522 After the section name comes another field, a number, which for
524 common symbols is the alignment and for other symbol is the size.
525 Finally the symbol's name is displayed.
526 The flag characters are divided into 7 groups as follows:
528 "l"
530 "g"
531 "u"
532 "!" The symbol is a local (l), global (g), unique global (u),
533 neither global nor local (a space) or both global and local
534 (!). A symbol can be neither local or global for a variety of
535 reasons, e.g., because it is used for debugging, but it is
536 probably an indication of a bug if it is ever both local and
537 global. Unique global symbols are a GNU extension to the
538 standard set of ELF symbol bindings. For such a symbol the
539 dynamic linker will make sure that in the entire process there
540 is just one symbol with this name and type in use.
541 "w" The symbol is weak (w) or strong (a space).
543 "C" The symbol denotes a constructor (C) or an ordinary symbol (a
545 space).
546 "W" The symbol is a warning (W) or a normal symbol (a space). A
548 warning symbol's name is a message to be displayed if the
549 symbol following the warning symbol is ever referenced.
550 "I"
552 "i" The symbol is an indirect reference to another symbol (I), a
553 function to be evaluated during reloc processing (i) or a
554 normal symbol (a space).
555 "d"
557 "D" The symbol is a debugging symbol (d) or a dynamic symbol (D) or
558 a normal symbol (a space).
559 "F"
561 "f"
562 "O" The symbol is the name of a function (F) or a file (f) or an
563 object (O) or just a normal symbol (a space).
564 -T
566 --dynamic-syms
567 Print the dynamic symbol table entries of the file. This is only
568 meaningful for dynamic objects, such as certain types of shared
569 libraries. This is similar to the information provided by the nm
570 program when given the -D (--dynamic) option.
571 --special-syms
573 When displaying symbols include those which the target considers to
574 be special in some way and which would not normally be of interest
575 to the user.
576 -V
578 --version
579 Print the version number of objdump and exit.
580 -x
582 --all-headers
583 Display all available header information, including the symbol
584 table and relocation entries. Using -x is equivalent to specifying
585 all of -a -f -h -p -r -t.
586 -w
588 --wide
589 Format some lines for output devices that have more than 80
590 columns. Also do not truncate symbol names when they are
591 displayed.
592 -z
594 --disassemble-zeroes
595 Normally the disassembly output will skip blocks of zeroes. This
596 option directs the disassembler to disassemble those blocks, just
597 like any other data.
598 @file
600 Read command-line options from file. The options read are inserted
601 in place of the original @file option. If file does not exist, or
602 cannot be read, then the option will be treated literally, and not
603 removed.
604 Options in file are separated by whitespace. A whitespace
606 character may be included in an option by surrounding the entire
607 option in either single or double quotes. Any character (including
608 a backslash) may be included by prefixing the character to be
609 included with a backslash. The file may itself contain additional
610 @file options; any such options will be processed recursively.
611
613 nm(1), readelf(1), and the Info entries for binutils.
614
616 Copyright (c) 1991-2016 Free Software Foundation, Inc.
617 Permission is granted to copy, distribute and/or modify this document
619 under the terms of the GNU Free Documentation License, Version 1.3 or
620 any later version published by the Free Software Foundation; with no
621 Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
622 Texts. A copy of the license is included in the section entitled "GNU
623 Free Documentation License".
624binutils-2.27 2016-08-03 OBJDUMP(1)