Provided by: binutils_2.18.93.20081009-0ubuntu1_i386 bug


       objdump - display information from object files.


       objdump [-a--archive-headers]
               [-b bfdname--target=bfdname]
               [-C--demangle[=style] ]
               [-EB-EL--endian={big │ little }]
               [-j section--section=section]
               [-m machine--architecture=machine]
               [-M options--disassembler-options=options]


       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     from     the     list
       -a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x must be given.

           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.

           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
           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.

           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

           Display debugging information.  This attempts to  parse  STABS  and
           IEEE  debugging  format information stored in the file and print it
           out using a C like syntax.  If neither of these formats  are  found
           this  option  falls  back  on  the  -W  option  to  print any DWARF
           information in the file.

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

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

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

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

           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.

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

           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.

           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.

           Display  summary information from the section headers of the object

           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

           Print a summary of the options to objdump and exit.

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

       -j name
           Display information only for section name.

           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
           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
           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.

           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

           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

           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
           architecture.   intel  and att select between intel syntax mode and
           AT&T syntax mode.  intel-mnemonic and att-mnemonic  select  between
           intel  mnemonic mode and AT&T mnemonic mode. intel-mnemonic implies
           intel and att-mnemonic implies att.  addr64, addr32, addr16, data32
           and  data16  specify  the  default  address  size and operand size.
           These four options will be overridden  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.   e300  selects disassembly for the e300 family.  440
           selects disassembly for the PowerPC 440.  ppcps selects disassembly
           for the paired single instructions of the PPC750CL.

           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:

               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.

               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.

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

               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.

               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.

               Print GPR and FPR names as appropriate for the selected ABI.

               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.

           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.

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

           Print the dynamic relocation entries of the  file.   This  is  only
           meaningful  for  dynamic  objects,  such as certain types of shared

           Display the full contents of any sections  requested.   By  default
           all non-empty sections are displayed.

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

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

           When disassembling  instructions,  do  not  print  the  instruction
           bytes.  This is the default when --prefix-addresses is used.

           Displays  the  contents of the DWARF debug sections in the file, if
           any are present.

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

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

           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  auxilary  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  refered  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:

           "!" The symbol is local (l), global (g), neither (a space) or  both
               (!).   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

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

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

           "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" The  symbol is an indirect reference to another symbol (I) or a
               normal symbol (a space).

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

           "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).

           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.

           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.

           Print the version number of objdump and exit.

           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.

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

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

           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

           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.


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


       Copyright  (c)  1991,  1992,  1993, 1994, 1995, 1996, 1997, 1998, 1999,
       2000, 2001, 2002, 2003, 2004, 2005,  2006,  2007,  2008  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  1.2  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".