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NAME
    objdump - display information from object files.

SYNOPSIS
    objdump [-a|--archive-headers]
     [-b bfdname|--target=bfdname]
     [-C|--demangle[=style] ]
     [-d|--disassemble]
     [-D|--disassemble-all]
     [-z|--disassemble-zeroes]
     [-EB|-EL|--endian={big | little }]
     [-f|--file-headers]
     [--file-start-context]
     [-g|--debugging]
     [-h|--section-headers|--headers]
     [-i|--info]
     [-j section|--section=section]
     [-l|--line-numbers]
     [-S|--source]
     [-m machine|--architecture=machine]
     [-M options|--disassembler-options=options]
     [-p|--private-headers]
     [-r|--reloc]
     [-R|--dynamic-reloc]
     [-s|--full-contents]
     [-G|--stabs]
     [-t|--syms]
     [-T|--dynamic-syms]
     [-x|--all-headers]
     [-w|--wide]
     [--start-address=address]
     [--stop-address=address]
     [--prefix-addresses]
     [--[no-]show-raw-insn]
     [--adjust-vma=offset]
     [-V|--version]
     [-H|--help]
     objfile...

DESCRIPTION
    objdump displays information about one or more object files. The
    options control what particular information to display. This informa-
    tion 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,-f,-g,-G,-h,-H,-p,-r,-R,-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 sec-
   tions 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 bfd-
   name.  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 com-
   piler.

    -G
    --debugging
   Display debugging information. This attempts to parse debugging
   information stored in the file and print it out using a C like syn-
   tax.  Only certain types of debugging information have been imple-
   mented.

    -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.

    --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 dis-
   assembly. This can be useful when disassembling a file format
   which does not describe endianness information, such as S-records.

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

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

   File segments may be relocated to nonstandard addresses, for  exam-
   ple 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 avail-
   able 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 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.

    -M options
    --disassembler-options=options
   Pass target specific information to the disassembler.  Only sup-
   ported on some targets.

   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-name-std (the default) will select the register
   names as used in ARM's instruction set documentation, but with reg-
   ister 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  name 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 the x86, some of the options duplicate functions of the -m
   switch, but allow finer grained control. Multiple selections from
   the following may be specified as a comma separated string.
   x86-64, i386 and i8086 select disassembly for the given architec-
   ture. intel and att select between intel syntax mode and AT&T syn-
   tax mode. addr32,  addr16, data32 and data16 specify the default
   address size and operand size. These four options will be overrid-
   den if x86-64, i386 or i8086 appear later in the option string.
   Lastly, suffix, when in AT&T mode, instructs  the disassembler to
   print a mnemonic suffix even when the suffix could be inferred by
   the operands.

   For PPC, booke, booke32 and booke64 select disassembly of  BookE
   instructions.  32 and 64 select PowerPC and PowerPC64 disassembly,
   respectively.

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

   "gpr-names=ABI"
     Print GPR (general-purpose register) names as appropriate for
     the specified ABI. By default, GPR names are selected accord-
     ing 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.

    -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.

    -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.  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.

    -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.

    -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 ta-
   ble and relocation entries. Using -x is equivalent to specifying
   all of -a -f -h -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 dis-
   played.

    -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.

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

COPYRIGHT
    Copyright (c) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002
    Free Software Foundation, Inc.

    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.1 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".