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OBJDUMP(1)		     GNU Development Tools		    OBJDUMP(1)

       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 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.

       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.

	   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.

	   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
	   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.

	   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-

	   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-

	   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.

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

	   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.

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

	   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	 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.

	   Print a summary of the options to objdump and exit.

	   Display a list showing all architectures and	object formats	avail-
	   able	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 de-
	   scribe  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  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  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 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

	   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 dissassembler 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,

	   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 li-

	   Display the full contents of	any sections requested.

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

	   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.

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

	   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.

	   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.

	   Print the version number of objdump and exit.

	   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.

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

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

       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".

3rd Berkeley Distribution	  2002-08-05			    OBJDUMP(1)


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