Yolinux.com

objdump manpage

Search topic Section
Get manual page for the search topic
List all commands matching the search topic
List all topics in the manpage index

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]
	       [-W|--dwarf]
	       [-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
       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,-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-names-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.  e300 selects disassembly for the e300 family.

	   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.

	   "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.

	   For	VAX,  you  can	specify	 function  entry  addresses  with   -M
	   entry:0xf00ba.   You can use this multiple times to properly disas-
	   semble 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.

       -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.

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

       -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
	   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.

       @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 charac-
	   ter 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.

COPYRIGHT
       Copyright (c) 1991, 1992, 1993, 1994, 1995,  1996,  1997,  1998,	 1999,
       2000, 2001, 2002, 2003, 2004, 2005, 2006 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-2.17.50.0.6-26.el5	  2013-10-01			    OBJDUMP(1)
YoLinux.com Home Page
YoLinux Tutorial Index
Privacy Policy | Advertise with us | Feedback Form |
Unauthorized copying or redistribution prohibited.
    Bookmark and Share