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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 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 pro-
       gram 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 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 use-
	   ful 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 repre-
	   sent section addresses, such as a.out.

       -b bfdname
       --target=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 explic-
	   itly 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 compiler.

       -g
       --debugging
	   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.

       -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 con-
	   tain instructions.

       --prefix-addresses
	   When disassembling, print the complete address on each line.  This is the older disas-
	   sembly format.

       -EB
       -EL
       --endian={big|little}
	   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 informa-
	   tion, 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  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 sec-
	   tion 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 available for specifica-
	   tion 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 num-
	   bers  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 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 reg-
	   ister  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  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 names).

	   This option can also be used for ARM architectures to force the disassembler to inter-
	   pret  all  instructions  as	Thumb  instructions  by  using	the  switch   --disassem-
	   bler-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 syntax mode.  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.

	   For MIPS, this option controls the printing of register names in disassembled instruc-
	   tions.   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 according to the ABI of the binary being disas-
	       sembled.

	   "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 appropri-
	       ate 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 disassem-
	       bled.

	   "hwr-names=ARCH"
	       Print HWR (hardware register, used by the "rdhwr" instruction) names as	appropri-
	       ate  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  addi-
	   tional 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.  By default all non-empty sec-
	   tions are displayed.

       -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 --prefix-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  pro-
	   vided 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.

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

       -x
       --all-headers
	   Display  all  available  header information, including the symbol table 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  columns.   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''.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +--------------------+-----------------+
       |  ATTRIBUTE TYPE    | ATTRIBUTE VALUE |
       +--------------------+-----------------+
       |Availability	    | SUNWbinutils    |
       +--------------------+-----------------+
       |Interface Stability | External	      |
       +--------------------+-----------------+
NOTES
       Source for GNU binutils is available on http://opensolaris.org.

binutils-2.14.91			    2004-04-09				       OBJDUMP(1)
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