objdump

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objdump

objdump [ -a | --archive-headers ]
[ -b bfdname | --target=bfdname ] [ --debugging ]
[ -d | --disassemble ] [ -D | --disassemble-all ]
[ -f | --file-headers ]
[ -h | --section-headers | --headers ]
[ -i | --info ]
[ -j section | --section=section ]
[ -l | --line-numbers ] [ -S | --source ]
[ -m machine | --architecture=machine ]
[ -r | --reloc ] [ -R | --dynamic-reloc ]
[ -s | --full-contents ] [ --stabs ]
[ -t | --syms ] [ -T | --dynamic-syms ]
[ -x | --all-headers ]
[ -w | --wide ] [ --start-address=address ]
[ --stop-address=address ]
[ --show-raw-insn ]
[ --version ]
[ --help ]
objfile...

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.

The long and short forms of options, shown here as alternatives, are equivalent. At least one option besides ‘-l’ 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.

-bbfdname
--target=bfdname

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

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

The previous example 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. See Target selection for more information.

--debugging

Display debugging information. This attempts to parse debugging information stored in the file and print it out using a C like syntax. Only certain types of debugging information have been implemented.

-d
--disassemble

Display the assembler mnemonics for the machine instructions from objfile. This option only disassembles those sections which are expected to contain instructions.

-D
--disassemble-all

Like ‘-d’, but disassemble the contents of all sections, not just those expected to contain instructions.

-f
--file-header

Display summary information from the overall header of each of the objfile files.

-h
--section-header
--header

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.

--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 only for section name.

-l
--line-numbers

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

-m machine
--architecture=machine

Specify that the object files objfile are for architecture machine. You can list available architectures using the ‘-i’ option.

-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.

-s
--full-contents

Display the full contents of any sections requested.

-S
--source

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

--show-raw-insn

When disassembling instructions, print the instruction in hex as well as in symbolic form. Not all targets handle this correctly yet.

--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. For more information on stabs symbols, see the directives, .stabd, .stabn, .stabs in Assembler directives in Using `as`.

--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.

-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.

--version

Print the version number of objdump and exit.

-x
--all-header

Display all available header information, including the symbol table and relocation entries.
Using ‘-x’ is equivalent to specifying all of ‘-a-f -h -r -t’.

-w
--wide

Format some lines for output devices having more than 80 columns.

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