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Manual: objdump

OBJDUMP(1) GNU Development Tools OBJDUMP(1)

NAME
objdump - display information from object files

SYNOPSIS
objdump [-a|--archive-headers]
[-b bfdname|--target=bfdname]
[-C|--demangle[=style] ]
[-d|--disassemble[=symbol]]
[-D|--disassemble-all]
[-z|--disassemble-zeroes]
[-EB|-EL|--endian={big | little }]
[-f|--file-headers]
[-F|--file-offsets]
[--file-start-context]
[-g|--debugging]
[-e|--debugging-tags]
[-h|--section-headers|--headers]
[-i|--info]
[-j section|--section=section]
[-l|--line-numbers]
[-S|--source]
[--source-comment[=text]]
[-m machine|--architecture=machine]
[-M options|--disassembler-options=options]
[-p|--private-headers]
[-P options|--private=options]
[-r|--reloc]
[-R|--dynamic-reloc]
[-s|--full-contents]
[-Z|--decompress]
[-W[lLiaprmfFsoORtUuTgAck]|
--dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links]]
[-WK|--dwarf=follow-links]
[-WN|--dwarf=no-follow-links]
[-wD|--dwarf=use-debuginfod]
[-wE|--dwarf=do-not-use-debuginfod]
[-L|--process-links]
[--ctf=section]
[--sframe=section]
[-G|--stabs]
[-t|--syms]
[-T|--dynamic-syms]
[-x|--all-headers]
[-w|--wide]
[--start-address=address]
[--stop-address=address]
[--no-addresses]
[--prefix-addresses]
[--[no-]show-raw-insn]
[--adjust-vma=offset]
[--show-all-symbols]
[--dwarf-depth=n]
[--dwarf-start=n]
[--ctf-parent=section]
[--no-recurse-limit|--recurse-limit]
[--special-syms]
[--prefix=prefix]
[--prefix-strip=level]
[--insn-width=width]
[--visualize-jumps[=color|=extended-color|=off]
[--disassembler-color=[off|terminal|on|extended]
[-U method] [--unicode=method]
[-V|--version]
[-H|--help]
objfile...

DESCRIPTION
objdump displays information about one or more object files. The options control what particular information to
display. This information is mostly useful to programmers who are working on the compilation tools, as opposed to
programmers who just want their program to compile and work.

objfile... are the object files to be examined. When you specify archives, objdump shows information on each of the
member object files.

OPTIONS
The long and short forms of options, shown here as alternatives, are equivalent. At least one option from the list
-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-P,-r,-R,-s,-S,-t,-T,-V,-x must be given.

-a
--archive-header
If any of the objfile files are archives, display the archive header information (in a format similar to ls -l).
Besides the information you could list with ar tv, objdump -a shows the object file format of each archive
member.

--adjust-vma=offset
When dumping information, first add offset to all the section addresses. This is useful if the section addresses
do not correspond to the symbol table, which can happen when putting sections at particular addresses when using
a format which can not represent section addresses, such as a.out.

-b bfdname
--target=bfdname
Specify that the object-code format for the object files is bfdname. This option may not be necessary; objdump
can automatically recognize many formats.

For example,

objdump -b oasys -m vax -h fu.o

displays summary information from the section headers (-h) of fu.o, which is explicitly identified (-m) as a VAX
object file in the format produced by Oasys compilers. You can list the formats available with the -i option.

-C
--demangle[=style]
Decode (demangle) low-level symbol names into user-level names. Besides removing any initial underscore
prepended by the system, this makes C++ function names readable. Different compilers have different mangling
styles. The optional demangling style argument can be used to choose an appropriate demangling style for your
compiler.

--recurse-limit
--no-recurse-limit
--recursion-limit
--no-recursion-limit
Enables or disables a limit on the amount of recursion performed whilst demangling strings. Since the name
mangling formats allow for an infinite level of recursion it is possible to create strings whose decoding will
exhaust the amount of stack space available on the host machine, triggering a memory fault. The limit tries to
prevent this from happening by restricting recursion to 2048 levels of nesting.

The default is for this limit to be enabled, but disabling it may be necessary in order to demangle truly
complicated names. Note however that if the recursion limit is disabled then stack exhaustion is possible and
any bug reports about such an event will be rejected.

-g
--debugging
Display debugging information. This attempts to parse STABS debugging format information stored in the file and
print it out using a C like syntax. If no STABS debugging was found this option falls back on the -W option to
print any DWARF information in the file.

-e
--debugging-tags
Like -g, but the information is generated in a format compatible with ctags tool.

-d
--disassemble
--disassemble=symbol
Display the assembler mnemonics for the machine instructions from the input file. This option only disassembles
those sections which are expected to contain instructions. If the optional symbol argument is given (perhaps
multiple times), then display the assembler mnemonics starting at (all the) symbol. If symbol is a function name
then disassembly will stop at the end of the function, otherwise it will stop when the next symbol is
encountered. If there are no matches for any symbol then nothing will be displayed.

Note if the --dwarf=follow-links option is enabled then any symbol tables in linked debug info files will be read
in and used when disassembling.

-D
--disassemble-all
Like -d, but disassemble the contents of all non-empty non-bss sections, not just those expected to contain
instructions. -j may be used to select specific sections.

This option also has a subtle effect on the disassembly of instructions in code sections. When option -d is in
effect objdump will assume that any symbols present in a code section occur on the boundary between instructions
and it will refuse to disassemble across such a boundary. When option -D is in effect however this assumption is
supressed. This means that it is possible for the output of -d and -D to differ if, for example, data is stored
in code sections.

If the target is an ARM architecture this switch also has the effect of forcing the disassembler to decode pieces
of data found in code sections as if they were instructions.

Note if the --dwarf=follow-links option is enabled then any symbol tables in linked debug info files will be read
in and used when disassembling.

--no-addresses
When disassembling, don't print addresses on each line or for symbols and relocation offsets. In combination
with --no-show-raw-insn this may be useful for comparing compiler output.

--prefix-addresses
When disassembling, print the complete address on each line. This is the older disassembly format.

-EB
-EL
--endian={big|little}
Specify the endianness of the object files. This only affects disassembly. This can be useful when
disassembling a file format which does not describe endianness information, such as S-records.

-f
--file-headers
Display summary information from the overall header of each of the objfile files.

-F
--file-offsets
When disassembling sections, whenever a symbol is displayed, also display the file offset of the region of data
that is about to be dumped. If zeroes are being skipped, then when disassembly resumes, tell the user how many
zeroes were skipped and the file offset of the location from where the disassembly resumes. When dumping
sections, display the file offset of the location from where the dump starts.

--file-start-context
Specify that when displaying interlisted source code/disassembly (assumes -S) from a file that has not yet been
displayed, extend the context to the start of the file.

-h
--section-headers
--headers
Display summary information from the section headers of the object file.

File segments may be relocated to nonstandard addresses, for example by using the -Ttext, -Tdata, or -Tbss
options to ld. However, some object file formats, such as a.out, do not store the starting address of the file
segments. In those situations, although ld relocates the sections correctly, using objdump -h to list the file
section headers cannot show the correct addresses. Instead, it shows the usual addresses, which are implicit for
the target.

Note, in some cases it is possible for a section to have both the READONLY and the NOREAD attributes set. In
such cases the NOREAD attribute takes precedence, but objdump will report both since the exact setting of the
flag bits might be important.

-H
--help
Print a summary of the options to objdump and exit.

-i
--info
Display a list showing all architectures and object formats available for specification with -b or -m.

-j name
--section=name
Display information for section name. This option may be specified multiple times.

-L
--process-links
Display the contents of non-debug sections found in separate debuginfo files that are linked to the main file.
This option automatically implies the -WK option, and only sections requested by other command line options will
be displayed.

-l
--line-numbers
Label the display (using debugging information) with the filename and source line numbers corresponding to the
object code or relocs shown. Only useful with -d, -D, or -r.

-m machine
--architecture=machine
Specify the architecture to use when disassembling object files. This can be useful when disassembling object
files which do not describe architecture information, such as S-records. You can list the available
architectures with the -i option.

For most architectures it is possible to supply an architecture name and a machine name, separated by a colon.
For example foo:bar would refer to the bar machine type in the foo architecture. This can be helpful if objdump
has been configured to support multiple architectures.

If the target is an ARM architecture then this switch has an additional effect. It restricts the disassembly to
only those instructions supported by the architecture specified by machine. If it is necessary to use this
switch because the input file does not contain any architecture information, but it is also desired to
disassemble all the instructions use -marm.

-M options
--disassembler-options=options
Pass target specific information to the disassembler. Only supported on some targets. If it is necessary to
specify more than one disassembler option then multiple -M options can be used or can be placed together into a
comma separated list.

For ARC, dsp controls the printing of DSP instructions, spfp selects the printing of FPX single precision FP
instructions, dpfp selects the printing of FPX double precision FP instructions, quarkse_em selects the printing
of special QuarkSE-EM instructions, fpuda selects the printing of double precision assist instructions, fpus
selects the printing of FPU single precision FP instructions, while fpud selects the printing of FPU double
precision FP instructions. Additionally, one can choose to have all the immediates printed in hexadecimal using
hex. By default, the short immediates are printed using the decimal representation, while the long immediate
values are printed as hexadecimal.

cpu=... allows one to enforce a particular ISA when disassembling instructions, overriding the -m value or
whatever is in the ELF file. This might be useful to select ARC EM or HS ISA, because architecture is same for
those and disassembler relies on private ELF header data to decide if code is for EM or HS. This option might be
specified multiple times - only the latest value will be used. Valid values are same as for the assembler
-mcpu=... option.

If the target is an ARM architecture then this switch can be used to select which register name set is used
during disassembler. Specifying -M reg-names-std (the default) will select the register names as used in ARM's
instruction set documentation, but with register 13 called 'sp', register 14 called 'lr' and register 15 called
'pc'. Specifying -M reg-names-apcs will select the name set used by the ARM Procedure Call Standard, whilst
specifying -M reg-names-raw will just use r followed by the register number.

There are also two variants on the APCS register naming scheme enabled by -M reg-names-atpcs and -M reg-names-
special-atpcs which use the ARM/Thumb Procedure Call Standard naming conventions. (Either with the normal
register names or the special register names).

This option can also be used for ARM architectures to force the disassembler to interpret all instructions as
Thumb instructions by using the switch --disassembler-options=force-thumb. This can be useful when attempting to
disassemble thumb code produced by other compilers.

For AArch64 targets this switch can be used to set whether instructions are disassembled as the most general
instruction using the -M no-aliases option or whether instruction notes should be generated as comments in the
disasssembly using -M notes.

For the x86, some of the options duplicate functions of the -m switch, but allow finer grained control.

"x86-64"
"i386"
"i8086"
Select disassembly for the given architecture.

"intel"
"att"
Select between intel syntax mode and AT&T syntax mode.

"amd64"
"intel64"
Select between AMD64 ISA and Intel64 ISA.

"intel-mnemonic"
"att-mnemonic"
Select between intel mnemonic mode and AT&T mnemonic mode. Note: "intel-mnemonic" implies "intel" and
"att-mnemonic" implies "att".

"addr64"
"addr32"
"addr16"
"data32"
"data16"
Specify the default address size and operand size. These five options will be overridden if "x86-64", "i386"
or "i8086" appear later in the option string.

"suffix"
When in AT&T mode and also for a limited set of instructions when in Intel mode, instructs the disassembler
to print a mnemonic suffix even when the suffix could be inferred by the operands or, for certain
instructions, the execution mode's defaults.

For PowerPC, the -M argument raw selects disasssembly of hardware insns rather than aliases. For example, you
will see "rlwinm" rather than "clrlwi", and "addi" rather than "li". All of the -m arguments for gas that select
a CPU are supported. These are: 403, 405, 440, 464, 476, 601, 603, 604, 620, 7400, 7410, 7450, 7455, 750cl, 821,
850, 860, a2, booke, booke32, cell, com, e200z2, e200z4, e300, e500, e500mc, e500mc64, e500x2, e5500, e6500, efs,
power4, power5, power6, power7, power8, power9, power10, power11, ppc, ppc32, ppc64, ppc64bridge, ppcps, pwr,
pwr2, pwr4, pwr5, pwr5x, pwr6, pwr7, pwr8, pwr9, pwr10, pwr11, pwrx, titan, vle, and future. 32 and 64 modify
the default or a prior CPU selection, disabling and enabling 64-bit insns respectively. In addition, altivec,
any, lsp, htm, vsx, spe and spe2 add capabilities to a previous or later CPU selection. any will disassemble
any opcode known to binutils, but in cases where an opcode has two different meanings or different arguments, you
may not see the disassembly you expect. If you disassemble without giving a CPU selection, a default will be
chosen from information gleaned by BFD from the object files headers, but the result again may not be as you
expect.

For RISC-V, the following options are supported:

"max"
Disassemble without checking architecture string. This is a best effort mode, so for overlapping ISA
extensions the first match (possibly incorrect in a given context) will be used to decode the instruction.
It's useful, if the ELF file doesn't expose ISA string, preventing automatic ISA subset deduction, and the
default fallback ISA string ("rv64gc") doesn't cover all instructions in the binary.

"numeric"
Print numeric register names, rather than ABI names (e.g., print "x2" instead of "sp").

"no-aliases"
Disassemble only into canonical instructions. For example, compressed instructions will be represented as
such ("addi sp,sp,-128" will be "c.addi16sp sp,-128").

"priv-spec=SPEC"
Print the CSR according to the chosen privilege spec version (e.g., 1.10, 1.11, 1.12, 1.13).

For MIPS, this option controls the printing of instruction mnemonic names and register names in disassembled
instructions. Multiple selections from the following may be specified as a comma separated string, and invalid
options are ignored:

"no-aliases"
Print the 'raw' instruction mnemonic instead of some pseudo instruction mnemonic. I.e., print 'daddu' or
'or' instead of 'move', 'sll' instead of 'nop', etc.

"msa"
Disassemble MSA instructions.

"virt"
Disassemble the virtualization ASE instructions.

"xpa"
Disassemble the eXtended Physical Address (XPA) ASE instructions.

"gpr-names=ABI"
Print GPR (general-purpose register) names as appropriate for the specified ABI. By default, GPR names are
selected according to the ABI of the binary being disassembled.

"fpr-names=ABI"
Print FPR (floating-point register) names as appropriate for the specified ABI. By default, FPR numbers are
printed rather than names.

"cp0-names=ARCH"
Print CP0 (system control coprocessor; coprocessor 0) register names as appropriate for the CPU or
architecture specified by ARCH. By default, CP0 register names are selected according to the architecture
and CPU of the binary being disassembled.

"hwr-names=ARCH"
Print HWR (hardware register, used by the "rdhwr" instruction) names as appropriate for the CPU or
architecture specified by ARCH. By default, HWR names are selected according to the architecture and CPU of
the binary being disassembled.

"reg-names=ABI"
Print GPR and FPR names as appropriate for the selected ABI.

"reg-names=ARCH"
Print CPU-specific register names (CP0 register and HWR names) as appropriate for the selected CPU or
architecture.

For any of the options listed above, ABI or ARCH may be specified as numeric to have numbers printed rather than
names, for the selected types of registers. You can list the available values of ABI and ARCH using the --help
option.

For VAX, you can specify function entry addresses with -M entry:0xf00ba. You can use this multiple times to
properly disassemble VAX binary files that don't contain symbol tables (like ROM dumps). In these cases, the
function entry mask would otherwise be decoded as VAX instructions, which would probably lead the rest of the
function being wrongly disassembled.

-p
--private-headers
Print information that is specific to the object file format. The exact information printed depends upon the
object file format. For some object file formats, no additional information is printed.

-P options
--private=options
Print information that is specific to the object file format. The argument options is a comma separated list
that depends on the format (the lists of options is displayed with the help).

For XCOFF, the available options are:

"header"
"aout"
"sections"
"syms"
"relocs"
"lineno,"
"loader"
"except"
"typchk"
"traceback"
"toc"
"ldinfo"

For PE, the available options are:

"header"
"sections"

Not all object formats support this option. In particular the ELF format does not use it.

-r
--reloc
Print the relocation entries of the file. If used with -d or -D, the relocations are printed interspersed with
the disassembly.

-R
--dynamic-reloc
Print the dynamic relocation entries of the file. This is only meaningful for dynamic objects, such as certain
types of shared libraries. As for -r, if used with -d or -D, the relocations are printed interspersed with the
disassembly.

Note: objdump does not support displaying RELR type relocations. These can be displayed by the readelf program.

-s
--full-contents
Display the full contents of sections, often used in combination with -j to request specific sections. By
default all non-empty non-bss sections are displayed. By default any compressed section will be displayed in its
compressed form. In order to see the contents in a decompressed form add the -Z option to the command line.

-S
--source
Display source code intermixed with disassembly, if possible. Implies -d.

--show-all-symbols
When disassembling, show all the symbols that match a given address, not just the first one.

--source-comment[=txt]
Like the -S option, but all source code lines are displayed with a prefix of txt. Typically txt will be a
comment string which can be used to distinguish the assembler code from the source code. If txt is not provided
then a default string of "# " (hash followed by a space), will be used.

--prefix=prefix
Specify prefix to add to the absolute paths when used with -S.

--prefix-strip=level
Indicate how many initial directory names to strip off the hardwired absolute paths. It has no effect without
--prefix=prefix.

--show-raw-insn
When disassembling instructions, print the instruction in hex as well as in symbolic form. This is the default
except when --prefix-addresses is used.

--no-show-raw-insn
When disassembling instructions, do not print the instruction bytes. This is the default when --prefix-addresses
is used.

--insn-width=width
Display width bytes on a single line when disassembling instructions.

--visualize-jumps[=color|=extended-color|=off]
Visualize jumps that stay inside a function by drawing ASCII art between the start and target addresses. The
optional =color argument adds color to the output using simple terminal colors. Alternatively the
=extended-color argument will add color using 8bit colors, but these might not work on all terminals.

If it is necessary to disable the visualize-jumps option after it has previously been enabled then use
visualize-jumps=off.

--disassembler-color=off
--disassembler-color=terminal
--disassembler-color=on|color|colour
--disassembler-color=extended|extended-color|extended-colour
Enables or disables the use of colored syntax highlighting in disassembly output. The default behaviour is
determined via a configure time option. Note, not all architectures support colored syntax highlighting, and
depending upon the terminal used, colored output may not actually be legible.

The on argument adds colors using simple terminal colors.

The terminal argument does the same, but only if the output device is a terminal.

The extended-color argument is similar to the on argument, but it uses 8-bit colors. These may not work on all
terminals.

The off argument disables colored disassembly.

-W[lLiaprmfFsoORtUuTgAckK]
--dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=str-offsets,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges,=gdb_index,=addr,=cu_index,=links,=follow-links]
Displays the contents of the DWARF debug sections in the file, if any are present. Compressed debug sections are
automatically decompressed (temporarily) before they are displayed. If one or more of the optional letters or
words follows the switch then only those type(s) of data will be dumped. The letters and words refer to the
following information:

"a"
"=abbrev"
Displays the contents of the .debug_abbrev section.

"A"
"=addr"
Displays the contents of the .debug_addr section.

"c"
"=cu_index"
Displays the contents of the .debug_cu_index and/or .debug_tu_index sections.

"f"
"=frames"
Display the raw contents of a .debug_frame section.

"F"
"=frames-interp"
Display the interpreted contents of a .debug_frame section.

"g"
"=gdb_index"
Displays the contents of the .gdb_index and/or .debug_names sections.

"i"
"=info"
Displays the contents of the .debug_info section. Note: the output from this option can also be restricted
by the use of the --dwarf-depth and --dwarf-start options.

"k"
"=links"
Displays the contents of the .gnu_debuglink, .gnu_debugaltlink and .debug_sup sections, if any of them are
present. Also displays any links to separate dwarf object files (dwo), if they are specified by the
DW_AT_GNU_dwo_name or DW_AT_dwo_name attributes in the .debug_info section.

"K"
"=follow-links"
Display the contents of any selected debug sections that are found in linked, separate debug info file(s).
This can result in multiple versions of the same debug section being displayed if it exists in more than one
file.

In addition, when displaying DWARF attributes, if a form is found that references the separate debug info
file, then the referenced contents will also be displayed.

Note - in some distributions this option is enabled by default. It can be disabled via the N debug option.
The default can be chosen when configuring the binutils via the --enable-follow-debug-links=yes or
--enable-follow-debug-links=no options. If these are not used then the default is to enable the following of
debug links.

Note - if support for the debuginfod protocol was enabled when the binutils were built then this option will
also include an attempt to contact any debuginfod servers mentioned in the DEBUGINFOD_URLS environment
variable. This could take some time to resolve. This behaviour can be disabled via the
=do-not-use-debuginfod debug option.

"N"
"=no-follow-links"
Disables the following of links to separate debug info files.

"D"
"=use-debuginfod"
Enables contacting debuginfod servers if there is a need to follow debug links. This is the default
behaviour.

"E"
"=do-not-use-debuginfod"
Disables contacting debuginfod servers when there is a need to follow debug links.

"l"
"=rawline"
Displays the contents of the .debug_line section in a raw format.

"L"
"=decodedline"
Displays the interpreted contents of the .debug_line section.

"m"
"=macro"
Displays the contents of the .debug_macro and/or .debug_macinfo sections.

"o"
"=loc"
Displays the contents of the .debug_loc and/or .debug_loclists sections.

"O"
"=str-offsets"
Displays the contents of the .debug_str_offsets section.

"p"
"=pubnames"
Displays the contents of the .debug_pubnames and/or .debug_gnu_pubnames sections.

"r"
"=aranges"
Displays the contents of the .debug_aranges section.

"R"
"=Ranges"
Displays the contents of the .debug_ranges and/or .debug_rnglists sections.

"s"
"=str"
Displays the contents of the .debug_str, .debug_line_str and/or .debug_str_offsets sections.

"t"
"=pubtype"
Displays the contents of the .debug_pubtypes and/or .debug_gnu_pubtypes sections.

"T"
"=trace_aranges"
Displays the contents of the .trace_aranges section.

"u"
"=trace_abbrev"
Displays the contents of the .trace_abbrev section.

"U"
"=trace_info"
Displays the contents of the .trace_info section.

Note: displaying the contents of .debug_static_funcs, .debug_static_vars and debug_weaknames sections is not
currently supported.

--dwarf-depth=n
Limit the dump of the ".debug_info" section to n children. This is only useful with --debug-dump=info. The
default is to print all DIEs; the special value 0 for n will also have this effect.

With a non-zero value for n, DIEs at or deeper than n levels will not be printed. The range for n is zero-based.

--dwarf-start=n
Print only DIEs beginning with the DIE numbered n. This is only useful with --debug-dump=info.

If specified, this option will suppress printing of any header information and all DIEs before the DIE numbered
n. Only siblings and children of the specified DIE will be printed.

This can be used in conjunction with --dwarf-depth.

--dwarf-check
Enable additional checks for consistency of Dwarf information.

--ctf[=section]
Display the contents of the specified CTF section. CTF sections themselves contain many subsections, all of
which are displayed in order.

By default, display the name of the section named .ctf, which is the name emitted by ld.

--ctf-parent=member
If the CTF section contains ambiguously-defined types, it will consist of an archive of many CTF dictionaries,
all inheriting from one dictionary containing unambiguous types. This member is by default named .ctf, like the
section containing it, but it is possible to change this name using the "ctf_link_set_memb_name_changer" function
at link time. When looking at CTF archives that have been created by a linker that uses the name changer to
rename the parent archive member, --ctf-parent can be used to specify the name used for the parent.

--ctf-parent-section=section
This option lets you pick a completely different section for the CTF parent dictionary containing unambiguous
types than for the child dictionaries that contain the ambiguous remainder. The linker does not emit ELF objects
structured like this, but some third-party linkers may. It's also convenient to inspect CTF written out as
multiple raw files to compose them with objcopy, which can put them in different ELF sections but not in
different members of a single CTF dict.

--sframe[=section]
Display the contents of the specified SFrame section.

By default, display the name of the section named .sframe, which is the name emitted by ld.

-G
--stabs
Display the full contents of any sections requested. Display the contents of the .stab and .stab.index and
.stab.excl sections from an ELF file. This is only useful on systems (such as Solaris 2.0) in which ".stab"
debugging symbol-table entries are carried in an ELF section. In most other file formats, debugging symbol-table
entries are interleaved with linkage symbols, and are visible in the --syms output.

--start-address=address
Start displaying data at the specified address. This affects the output of the -d, -r and -s options.

--stop-address=address
Stop displaying data at the specified address. This affects the output of the -d, -r and -s options.

-t
--syms
Print the symbol table entries of the file. This is similar to the information provided by the nm program,
although the display format is different. The format of the output depends upon the format of the file being
dumped, but there are two main types. One looks like this:

[ 4](sec 3)(fl 0x00)(ty 0)(scl 3) (nx 1) 0x00000000 .bss
[ 6](sec 1)(fl 0x00)(ty 0)(scl 2) (nx 0) 0x00000000 fred

where the number inside the square brackets is the number of the entry in the symbol table, the sec number is the
section number, the fl value are the symbol's flag bits, the ty number is the symbol's type, the scl number is
the symbol's storage class and the nx value is the number of auxiliary entries associated with the symbol. The
last two fields are the symbol's value and its name.

The other common output format, usually seen with ELF based files, looks like this:

00000000 l d .bss 00000000 .bss
00000000 g .text 00000000 fred

Here the first number is the symbol's value (sometimes referred to as its address). The next field is actually a
set of characters and spaces indicating the flag bits that are set on the symbol. These characters are described
below. Next is the section with which the symbol is associated or *ABS* if the section is absolute (ie not
connected with any section), or *UND* if the section is referenced in the file being dumped, but not defined
there.

After the section name comes another field, a number, which for common symbols is the alignment and for other
symbol is the size. Finally the symbol's name is displayed.

The flag characters are divided into 7 groups as follows:

"l"
"g"
"u"
"!" The symbol is a local (l), global (g), unique global (u), neither global nor local (a space) or both global
and local (!). A symbol can be neither local or global for a variety of reasons, e.g., because it is used
for debugging, but it is probably an indication of a bug if it is ever both local and global. Unique global
symbols are a GNU extension to the standard set of ELF symbol bindings. For such a symbol the dynamic linker
will make sure that in the entire process there is just one symbol with this name and type in use.

"w" The symbol is weak (w) or strong (a space).

"C" The symbol denotes a constructor (C) or an ordinary symbol (a space).

"W" The symbol is a warning (W) or a normal symbol (a space). A warning symbol's name is a message to be
displayed if the symbol following the warning symbol is ever referenced.

"I"
"i" The symbol is an indirect reference to another symbol (I), a function to be evaluated during reloc processing
(i) or a normal symbol (a space).

"d"
"D" The symbol is a debugging symbol (d) or a dynamic symbol (D) or a normal symbol (a space).

"F"
"f"
"O" The symbol is the name of a function (F) or a file (f) or an object (O) or just a normal symbol (a space).

-T
--dynamic-syms
Print the dynamic symbol table entries of the file. This is only meaningful for dynamic objects, such as certain
types of shared libraries. This is similar to the information provided by the nm program when given the -D
(--dynamic) option.

The output format is similar to that produced by the --syms option, except that an extra field is inserted before
the symbol's name, giving the version information associated with the symbol. If the version is the default
version to be used when resolving unversioned references to the symbol then it's displayed as is, otherwise it's
put into parentheses.

--special-syms
When displaying symbols include those which the target considers to be special in some way and which would not
normally be of interest to the user.

-U [d|i|l|e|x|h]
--unicode=[default|invalid|locale|escape|hex|highlight]
Controls the display of UTF-8 encoded multibyte characters in strings. The default (--unicode=default) is to
give them no special treatment. The --unicode=locale option displays the sequence in the current locale, which
may or may not support them. The options --unicode=hex and --unicode=invalid display them as hex byte sequences
enclosed by either angle brackets or curly braces.

The --unicode=escape option displays them as escape sequences (\uxxxx) and the --unicode=highlight option
displays them as escape sequences highlighted in red (if supported by the output device). The colouring is
intended to draw attention to the presence of unicode sequences where they might not be expected.

-V
--version
Print the version number of objdump and exit.

-x
--all-headers
Display all available header information, including the symbol table and relocation entries. Using -x is
equivalent to specifying all of -a -f -h -p -r -t.

-w
--wide
Format some lines for output devices that have more than 80 columns. Also do not truncate symbol names when they
are displayed.

-z
--disassemble-zeroes
Normally the disassembly output will skip blocks of zeroes. This option directs the disassembler to disassemble
those blocks, just like any other data.

-Z
--decompress
The -Z option is meant to be used in conunction with the -s option. It instructs objdump to decompress any
compressed sections before displaying their contents.

@file
Read command-line options from file. The options read are inserted in place of the original @file option. If
file does not exist, or cannot be read, then the option will be treated literally, and not removed.

Options in file are separated by whitespace. A whitespace character may be included in an option by surrounding
the entire option in either single or double quotes. Any character (including a backslash) may be included by
prefixing the character to be included with a backslash. The file may itself contain additional @file options;
any such options will be processed recursively.

SEE ALSO
nm(1), readelf(1), and the Info entries for binutils.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation
License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with
no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU
Free Documentation License".

binutils-2.46 2026-03-15 OBJDUMP(1)

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