1OBJDUMP(1) GNU Development Tools OBJDUMP(1)
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6 objdump - display information from object files.
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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,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]]
35 [-G|--stabs]
36 [-t|--syms]
37 [-T|--dynamic-syms]
38 [-x|--all-headers]
39 [-w|--wide]
40 [--start-address=address]
41 [--stop-address=address]
42 [--prefix-addresses]
43 [--[no-]show-raw-insn]
44 [--adjust-vma=offset]
45 [--special-syms]
46 [--prefix=prefix]
47 [--prefix-strip=level]
48 [--insn-width=width]
49 [-V|--version]
50 [-H|--help]
51 objfile...
52
54 objdump displays information about one or more object files. The
55 options control what particular information to display. This
56 information is mostly useful to programmers who are working on the
57 compilation tools, as opposed to programmers who just want their
58 program to compile and work.
59
60 objfile... are the object files to be examined. When you specify
61 archives, objdump shows information on each of the member object files.
62
64 The long and short forms of options, shown here as alternatives, are
65 equivalent. At least one option from the list
66 -a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x must be given.
67
68 -a
69 --archive-header
70 If any of the objfile files are archives, display the archive
71 header information (in a format similar to ls -l). Besides the
72 information you could list with ar tv, objdump -a shows the object
73 file format of each archive member.
74
75 --adjust-vma=offset
76 When dumping information, first add offset to all the section
77 addresses. This is useful if the section addresses do not
78 correspond to the symbol table, which can happen when putting
79 sections at particular addresses when using a format which can not
80 represent section addresses, such as a.out.
81
82 -b bfdname
83 --target=bfdname
84 Specify that the object-code format for the object files is
85 bfdname. This option may not be necessary; objdump can
86 automatically recognize many formats.
87
88 For example,
89
90 objdump -b oasys -m vax -h fu.o
91
92 displays summary information from the section headers (-h) of fu.o,
93 which is explicitly identified (-m) as a VAX object file in the
94 format produced by Oasys compilers. You can list the formats
95 available with the -i option.
96
97 -C
98 --demangle[=style]
99 Decode (demangle) low-level symbol names into user-level names.
100 Besides removing any initial underscore prepended by the system,
101 this makes C++ function names readable. Different compilers have
102 different mangling styles. The optional demangling style argument
103 can be used to choose an appropriate demangling style for your
104 compiler.
105
106 -g
107 --debugging
108 Display debugging information. This attempts to parse STABS and
109 IEEE debugging format information stored in the file and print it
110 out using a C like syntax. If neither of these formats are found
111 this option falls back on the -W option to print any DWARF
112 information in the file.
113
114 -e
115 --debugging-tags
116 Like -g, but the information is generated in a format compatible
117 with ctags tool.
118
119 -d
120 --disassemble
121 Display the assembler mnemonics for the machine instructions from
122 objfile. This option only disassembles those sections which are
123 expected to contain instructions.
124
125 -D
126 --disassemble-all
127 Like -d, but disassemble the contents of all sections, not just
128 those expected to contain instructions.
129
130 If the target is an ARM architecture this switch also has the
131 effect of forcing the disassembler to decode pieces of data found
132 in code sections as if they were instructions.
133
134 --prefix-addresses
135 When disassembling, print the complete address on each line. This
136 is the older disassembly format.
137
138 -EB
139 -EL
140 --endian={big|little}
141 Specify the endianness of the object files. This only affects
142 disassembly. This can be useful when disassembling a file format
143 which does not describe endianness information, such as S-records.
144
145 -f
146 --file-headers
147 Display summary information from the overall header of each of the
148 objfile files.
149
150 -F
151 --file-offsets
152 When disassembling sections, whenever a symbol is displayed, also
153 display the file offset of the region of data that is about to be
154 dumped. If zeroes are being skipped, then when disassembly
155 resumes, tell the user how many zeroes were skipped and the file
156 offset of the location from where the disassembly resumes. When
157 dumping sections, display the file offset of the location from
158 where the dump starts.
159
160 --file-start-context
161 Specify that when displaying interlisted source code/disassembly
162 (assumes -S) from a file that has not yet been displayed, extend
163 the context to the start of the file.
164
165 -h
166 --section-headers
167 --headers
168 Display summary information from the section headers of the object
169 file.
170
171 File segments may be relocated to nonstandard addresses, for
172 example by using the -Ttext, -Tdata, or -Tbss options to ld.
173 However, some object file formats, such as a.out, do not store the
174 starting address of the file segments. In those situations,
175 although ld relocates the sections correctly, using objdump -h to
176 list the file section headers cannot show the correct addresses.
177 Instead, it shows the usual addresses, which are implicit for the
178 target.
179
180 -H
181 --help
182 Print a summary of the options to objdump and exit.
183
184 -i
185 --info
186 Display a list showing all architectures and object formats
187 available for specification with -b or -m.
188
189 -j name
190 --section=name
191 Display information only for section name.
192
193 -l
194 --line-numbers
195 Label the display (using debugging information) with the filename
196 and source line numbers corresponding to the object code or relocs
197 shown. Only useful with -d, -D, or -r.
198
199 -m machine
200 --architecture=machine
201 Specify the architecture to use when disassembling object files.
202 This can be useful when disassembling object files which do not
203 describe architecture information, such as S-records. You can list
204 the available architectures with the -i option.
205
206 If the target is an ARM architecture then this switch has an
207 additional effect. It restricts the disassembly to only those
208 instructions supported by the architecture specified by machine.
209 If it is necessary to use this switch because the input file does
210 not contain any architecture information, but it is also desired to
211 disassemble all the instructions use -marm.
212
213 -M options
214 --disassembler-options=options
215 Pass target specific information to the disassembler. Only
216 supported on some targets. If it is necessary to specify more than
217 one disassembler option then multiple -M options can be used or can
218 be placed together into a comma separated list.
219
220 If the target is an ARM architecture then this switch can be used
221 to select which register name set is used during disassembler.
222 Specifying -M reg-names-std (the default) will select the register
223 names as used in ARM's instruction set documentation, but with
224 register 13 called 'sp', register 14 called 'lr' and register 15
225 called 'pc'. Specifying -M reg-names-apcs will select the name set
226 used by the ARM Procedure Call Standard, whilst specifying -M reg-
227 names-raw will just use r followed by the register number.
228
229 There are also two variants on the APCS register naming scheme
230 enabled by -M reg-names-atpcs and -M reg-names-special-atpcs which
231 use the ARM/Thumb Procedure Call Standard naming conventions.
232 (Either with the normal register names or the special register
233 names).
234
235 This option can also be used for ARM architectures to force the
236 disassembler to interpret all instructions as Thumb instructions by
237 using the switch --disassembler-options=force-thumb. This can be
238 useful when attempting to disassemble thumb code produced by other
239 compilers.
240
241 For the x86, some of the options duplicate functions of the -m
242 switch, but allow finer grained control. Multiple selections from
243 the following may be specified as a comma separated string.
244 x86-64, i386 and i8086 select disassembly for the given
245 architecture. intel and att select between intel syntax mode and
246 AT&T syntax mode. intel-mnemonic and att-mnemonic select between
247 intel mnemonic mode and AT&T mnemonic mode. intel-mnemonic implies
248 intel and att-mnemonic implies att. addr64, addr32, addr16, data32
249 and data16 specify the default address size and operand size.
250 These four options will be overridden if x86-64, i386 or i8086
251 appear later in the option string. Lastly, suffix, when in AT&T
252 mode, instructs the disassembler to print a mnemonic suffix even
253 when the suffix could be inferred by the operands.
254
255 For PowerPC, booke controls the disassembly of BookE instructions.
256 32 and 64 select PowerPC and PowerPC64 disassembly, respectively.
257 e300 selects disassembly for the e300 family. 440 selects
258 disassembly for the PowerPC 440. ppcps selects disassembly for the
259 paired single instructions of the PPC750CL.
260
261 For MIPS, this option controls the printing of instruction mnemonic
262 names and register names in disassembled instructions. Multiple
263 selections from the following may be specified as a comma separated
264 string, and invalid options are ignored:
265
266 "no-aliases"
267 Print the 'raw' instruction mnemonic instead of some pseudo
268 instruction mnemonic. I.e., print 'daddu' or 'or' instead of
269 'move', 'sll' instead of 'nop', etc.
270
271 "virt"
272 Disassemble the virtualization ASE instructions.
273
274 "gpr-names=ABI"
275 Print GPR (general-purpose register) names as appropriate for
276 the specified ABI. By default, GPR names are selected
277 according to the ABI of the binary being disassembled.
278
279 "fpr-names=ABI"
280 Print FPR (floating-point register) names as appropriate for
281 the specified ABI. By default, FPR numbers are printed rather
282 than names.
283
284 "cp0-names=ARCH"
285 Print CP0 (system control coprocessor; coprocessor 0) register
286 names as appropriate for the CPU or architecture specified by
287 ARCH. By default, CP0 register names are selected according to
288 the architecture and CPU of the binary being disassembled.
289
290 "hwr-names=ARCH"
291 Print HWR (hardware register, used by the "rdhwr" instruction)
292 names as appropriate for the CPU or architecture specified by
293 ARCH. By default, HWR names are selected according to the
294 architecture and CPU of the binary being disassembled.
295
296 "reg-names=ABI"
297 Print GPR and FPR names as appropriate for the selected ABI.
298
299 "reg-names=ARCH"
300 Print CPU-specific register names (CP0 register and HWR names)
301 as appropriate for the selected CPU or architecture.
302
303 For any of the options listed above, ABI or ARCH may be specified
304 as numeric to have numbers printed rather than names, for the
305 selected types of registers. You can list the available values of
306 ABI and ARCH using the --help option.
307
308 For VAX, you can specify function entry addresses with -M
309 entry:0xf00ba. You can use this multiple times to properly
310 disassemble VAX binary files that don't contain symbol tables (like
311 ROM dumps). In these cases, the function entry mask would
312 otherwise be decoded as VAX instructions, which would probably lead
313 the rest of the function being wrongly disassembled.
314
315 -p
316 --private-headers
317 Print information that is specific to the object file format. The
318 exact information printed depends upon the object file format. For
319 some object file formats, no additional information is printed.
320
321 -P options
322 --private=options
323 Print information that is specific to the object file format. The
324 argument options is a comma separated list that depends on the
325 format (the lists of options is displayed with the help).
326
327 For XCOFF, the available options are: header, aout, sections, syms,
328 relocs, lineno, loader, except, typchk, traceback, toc and ldinfo.
329
330 -r
331 --reloc
332 Print the relocation entries of the file. If used with -d or -D,
333 the relocations are printed interspersed with the disassembly.
334
335 -R
336 --dynamic-reloc
337 Print the dynamic relocation entries of the file. This is only
338 meaningful for dynamic objects, such as certain types of shared
339 libraries. As for -r, if used with -d or -D, the relocations are
340 printed interspersed with the disassembly.
341
342 -s
343 --full-contents
344 Display the full contents of any sections requested. By default
345 all non-empty sections are displayed.
346
347 -S
348 --source
349 Display source code intermixed with disassembly, if possible.
350 Implies -d.
351
352 --prefix=prefix
353 Specify prefix to add to the absolute paths when used with -S.
354
355 --prefix-strip=level
356 Indicate how many initial directory names to strip off the
357 hardwired absolute paths. It has no effect without --prefix=prefix.
358
359 --show-raw-insn
360 When disassembling instructions, print the instruction in hex as
361 well as in symbolic form. This is the default except when
362 --prefix-addresses is used.
363
364 --no-show-raw-insn
365 When disassembling instructions, do not print the instruction
366 bytes. This is the default when --prefix-addresses is used.
367
368 --insn-width=width
369 Display width bytes on a single line when disassembling
370 instructions.
371
372 -W[lLiaprmfFsoRt]
373 --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index]
374 Displays the contents of the debug sections in the file, if any are
375 present. If one of the optional letters or words follows the
376 switch then only data found in those specific sections will be
377 dumped.
378
379 Note that there is no single letter option to display the content
380 of trace sections or .gdb_index.
381
382 Note: the output from the =info option can also be affected by the
383 options --dwarf-depth, the --dwarf-start and the --dwarf-check.
384
385 --dwarf-depth=n
386 Limit the dump of the ".debug_info" section to n children. This is
387 only useful with --dwarf=info. The default is to print all DIEs;
388 the special value 0 for n will also have this effect.
389
390 With a non-zero value for n, DIEs at or deeper than n levels will
391 not be printed. The range for n is zero-based.
392
393 --dwarf-start=n
394 Print only DIEs beginning with the DIE numbered n. This is only
395 useful with --dwarf=info.
396
397 If specified, this option will suppress printing of any header
398 information and all DIEs before the DIE numbered n. Only siblings
399 and children of the specified DIE will be printed.
400
401 This can be used in conjunction with --dwarf-depth.
402
403 --dwarf-check
404 Enable additional checks for consistency of Dwarf information.
405
406 -G
407 --stabs
408 Display the full contents of any sections requested. Display the
409 contents of the .stab and .stab.index and .stab.excl sections from
410 an ELF file. This is only useful on systems (such as Solaris 2.0)
411 in which ".stab" debugging symbol-table entries are carried in an
412 ELF section. In most other file formats, debugging symbol-table
413 entries are interleaved with linkage symbols, and are visible in
414 the --syms output.
415
416 --start-address=address
417 Start displaying data at the specified address. This affects the
418 output of the -d, -r and -s options.
419
420 --stop-address=address
421 Stop displaying data at the specified address. This affects the
422 output of the -d, -r and -s options.
423
424 -t
425 --syms
426 Print the symbol table entries of the file. This is similar to the
427 information provided by the nm program, although the display format
428 is different. The format of the output depends upon the format of
429 the file being dumped, but there are two main types. One looks
430 like this:
431
432 [ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
433 [ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred
434
435 where the number inside the square brackets is the number of the
436 entry in the symbol table, the sec number is the section number,
437 the fl value are the symbol's flag bits, the ty number is the
438 symbol's type, the scl number is the symbol's storage class and the
439 nx value is the number of auxilary entries associated with the
440 symbol. The last two fields are the symbol's value and its name.
441
442 The other common output format, usually seen with ELF based files,
443 looks like this:
444
445 00000000 l d .bss 00000000 .bss
446 00000000 g .text 00000000 fred
447
448 Here the first number is the symbol's value (sometimes refered to
449 as its address). The next field is actually a set of characters
450 and spaces indicating the flag bits that are set on the symbol.
451 These characters are described below. Next is the section with
452 which the symbol is associated or *ABS* if the section is absolute
453 (ie not connected with any section), or *UND* if the section is
454 referenced in the file being dumped, but not defined there.
455
456 After the section name comes another field, a number, which for
457 common symbols is the alignment and for other symbol is the size.
458 Finally the symbol's name is displayed.
459
460 The flag characters are divided into 7 groups as follows:
461
462 "l"
463 "g"
464 "u"
465 "!" The symbol is a local (l), global (g), unique global (u),
466 neither global nor local (a space) or both global and local
467 (!). A symbol can be neither local or global for a variety of
468 reasons, e.g., because it is used for debugging, but it is
469 probably an indication of a bug if it is ever both local and
470 global. Unique global symbols are a GNU extension to the
471 standard set of ELF symbol bindings. For such a symbol the
472 dynamic linker will make sure that in the entire process there
473 is just one symbol with this name and type in use.
474
475 "w" The symbol is weak (w) or strong (a space).
476
477 "C" The symbol denotes a constructor (C) or an ordinary symbol (a
478 space).
479
480 "W" The symbol is a warning (W) or a normal symbol (a space). A
481 warning symbol's name is a message to be displayed if the
482 symbol following the warning symbol is ever referenced.
483
484 "I"
485 "i" The symbol is an indirect reference to another symbol (I), a
486 function to be evaluated during reloc processing (i) or a
487 normal symbol (a space).
488
489 "d"
490 "D" The symbol is a debugging symbol (d) or a dynamic symbol (D) or
491 a normal symbol (a space).
492
493 "F"
494 "f"
495 "O" The symbol is the name of a function (F) or a file (f) or an
496 object (O) or just a normal symbol (a space).
497
498 -T
499 --dynamic-syms
500 Print the dynamic symbol table entries of the file. This is only
501 meaningful for dynamic objects, such as certain types of shared
502 libraries. This is similar to the information provided by the nm
503 program when given the -D (--dynamic) option.
504
505 --special-syms
506 When displaying symbols include those which the target considers to
507 be special in some way and which would not normally be of interest
508 to the user.
509
510 -V
511 --version
512 Print the version number of objdump and exit.
513
514 -x
515 --all-headers
516 Display all available header information, including the symbol
517 table and relocation entries. Using -x is equivalent to specifying
518 all of -a -f -h -p -r -t.
519
520 -w
521 --wide
522 Format some lines for output devices that have more than 80
523 columns. Also do not truncate symbol names when they are
524 displayed.
525
526 -z
527 --disassemble-zeroes
528 Normally the disassembly output will skip blocks of zeroes. This
529 option directs the disassembler to disassemble those blocks, just
530 like any other data.
531
532 @file
533 Read command-line options from file. The options read are inserted
534 in place of the original @file option. If file does not exist, or
535 cannot be read, then the option will be treated literally, and not
536 removed.
537
538 Options in file are separated by whitespace. A whitespace
539 character may be included in an option by surrounding the entire
540 option in either single or double quotes. Any character (including
541 a backslash) may be included by prefixing the character to be
542 included with a backslash. The file may itself contain additional
543 @file options; any such options will be processed recursively.
544
546 nm(1), readelf(1), and the Info entries for binutils.
547
549 Copyright (c) 1991-2013 Free Software Foundation, Inc.
550
551 Permission is granted to copy, distribute and/or modify this document
552 under the terms of the GNU Free Documentation License, Version 1.3 or
553 any later version published by the Free Software Foundation; with no
554 Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
555 Texts. A copy of the license is included in the section entitled "GNU
556 Free Documentation License".
557
558
559
560binutils-2.24 2020-01-29 OBJDUMP(1)