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]
               [-D|--disassemble-all]
               [-z|--disassemble-zeroes]
               [-EB|-EL|--endian={big | little }]
               [-f|--file-headers]
               [--file-start-context]
               [-g|--debugging]
               [-e|--debugging-tags]
               [-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]
               [--special-syms]
               [-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 ar-
       chives, 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,-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  corre-
           spond  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 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.  Some other types are supported by readelf -w.

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

       -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-headers
           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-headers
       --headers
           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.

       -H
       --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 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.

           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  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 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  instruction  mneu-
           monic  names and register names in disassembled instructions.  Mul-
           tiple selections from the following may be  specified  as  a  comma
           separated string, and invalid options are ignored:

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

           "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.   By  default
           all non-empty sections are displayed.

       -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 --pre-
           fix-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.

       --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.

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

       -x
       --all-headers
           Display  all available header information, including the symbol ta-
           ble 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 col-
           umns.  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.

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

COPYRIGHT
       Copyright (c) 1991, 1992, 1993, 1994, 1995,  1996,  1997,  1998,  1999,
       2000, 2001, 2002, 2003, 2004 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''.



binutils-2.15.97                  2005-04-20                        OBJDUMP(1)
