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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]
	       [-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
       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,-f,-g,-G,-h,-H,-p,-r,-R,-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.

       -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-header
	   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-header
       --header
	   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.

       --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  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	 name  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  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
	       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.

       -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.

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

       -x
       --all-header
	   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
       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-2.13.90.0.18		  2003-02-24			    OBJDUMP(1)

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

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