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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
       options 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.

       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.

	   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.

	   When	dumping	information, first add offset to all the section
	   addresses.  This is useful if the section addresses do not
	   correspond 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
	   Specify that	the object-code	format for the object files is
	   bfdname.  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

	   Display debugging information.  This	attempts to parse debugging
	   information stored in the file and print it out using a C like
	   syntax.  Only certain types of debugging information	have been
	   implemented.	 Some other types are supported	by readelf -w.

	   Like	-g, but	the information	is generated in	a format compatible
	   with	ctags tool.

	   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.

	   Specify the endianness of the object	files.	This only affects
	   disassembly.	 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
	   example 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

	   Print a summary of the options to objdump and exit.

	   Display a list showing all architectures and	object formats
	   available 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
	   describe 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
	   supported 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
	   register 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

	   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
	   architecture.  intel	and att	select between intel syntax mode and
	   AT&T	syntax mode.  addr64, addr32, addr16, data32 and data16
	   specify the default address size and	operand	size.  These four
	   options will	be overridden 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.	 440
	   selects disassembly for the PowerPC 440.

	   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:

	       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.

	       Print GPR (general-purpose register) names as appropriate for
	       the specified ABI.  By default, GPR names are selected
	       according to the	ABI of the binary being	disassembled.

	       Print FPR (floating-point register) names as appropriate	for
	       the specified ABI.  By default, FPR numbers are printed rather
	       than names.

	       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.

	       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.

	       Print GPR and FPR names as appropriate for the selected ABI.

	       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
	   disassemble 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.

	   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

	   Display the full contents of	any sections requested.	 By default
	   all non-empty sections are displayed.

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

	   When	disassembling instructions, print the instruction in hex as
	   well	as in symbolic form.  This is the default except when
	   --prefix-addresses is used.

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

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

	   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
	   libraries.  This is similar to the information provided by the nm
	   program when	given the -D (--dynamic) option.

	   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.

	   Print the version number of objdump and exit.

	   Display all available header	information, including the symbol
	   table and relocation	entries.  Using	-x is equivalent to specifying
	   all of -a -f	-h -p -r -t.

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

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

	   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

	   Options in file are separated by whitespace.	 A whitespace
	   character 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.

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

       Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
       2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 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		  2010-10-30			    OBJDUMP(1)


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