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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]
	       [-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 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 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 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-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 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.

	   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  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.

       -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.

       -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.

       -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 -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, 92, 93, 94, 95, 96, 97, 98, 99, 2000,  2001,	 2002,
       2003 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-2.14.91		  2004-04-09			    OBJDUMP(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COPYRIGHT

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