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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 op-
       tions 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.

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 in-
	   formation  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  ad-
	   dresses.  This is useful if the section addresses do	not correspond
	   to the symbol table,	which can happen when putting sections at par-
	   ticular  addresses when using a format which	can not	represent sec-
	   tion	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 re-
	   locates  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 de-
	   scribe  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 en-
	   abled by -M reg-names-atpcs and  -M	reg-names-special-atpcs	 which
	   use the ARM/Thumb Procedure Call Standard naming conventions.  (Ei-
	   ther	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 in-
	   structions.	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 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  ar-
	       chitecture 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 se-
	   lected 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 en-
	   try:0xf00ba.	 You can use this multiple times to properly disassem-
	   ble 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 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 li-
	   braries.

       -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.  Im-
	   plies -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 li-
	   braries.   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  in-
	   cluded  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			  2006-06-23			    OBJDUMP(1)

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