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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]
               [-F|--file-offsets]
               [--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]
               [-W[lLiaprmfFsoRt]|
                --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges]]
               [-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]
               [--special-syms]
               [--prefix=prefix]
               [--prefix-strip=level]
               [--insn-width=width]
               [-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
       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.

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 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
       --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 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
           compiler.

       -g
       --debugging
           Display debugging information.  This attempts to parse STABS and
           IEEE debugging format information stored in the file and print it
           out using a C like syntax.  If neither of these formats are found
           this option falls back on the -W option to print any DWARF
           information in the file.

       -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.

           If the target is an ARM architecture this switch also has the
           effect of forcing the disassembler to decode pieces of data found
           in code sections as if they were 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
           disassembly.  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.

       -F
       --file-offsets
           When disassembling sections, whenever a symbol is displayed, also
           display the file offset of the region of data that is about to be
           dumped.  If zeroes are being skipped, then when disassembly
           resumes, tell the user how many zeroes were skipped and the file
           offset of the location from where the disassembly resumes.  When
           dumping sections, display the file offset of the location from
           where the dump starts.

       --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 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
           available 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.

           If the target is an ARM architecture then this switch has an
           additional effect.  It restricts the disassembly to only those
           instructions supported by the architecture specified by machine.
           If it is necessary to use this switch because the input file does
           not contain any architecture information, but it is also desired to
           disassemble all the instructions use -marm.

       -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 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
           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
           architecture.  intel and att select between intel syntax mode and
           AT&T syntax mode.  intel-mnemonic and att-mnemonic select between
           intel mnemonic mode and AT&T mnemonic mode. intel-mnemonic implies
           intel and att-mnemonic implies att.  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 PowerPC, booke controls the 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.  ppcps selects disassembly for the
           paired single instructions of the PPC750CL.

           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:

           "no-aliases"
               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.

           "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 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.

           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.

       -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.  As for -r, if used with -d or -D, the relocations are
           printed interspersed with the disassembly.

       -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.
           Implies -d.

       --prefix=prefix
           Specify prefix to add to the absolute paths when used with -S.

       --prefix-strip=level
           Indicate how many initial directory names to strip off the
           hardwired absolute paths. It has no effect without --prefix=prefix.

       --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.

       --insn-width=width
           Display width bytes on a single line when disassembling
           instructions.

       -W[lLiaprmfFsoRt]
       --dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges,=pubtypes,=trace_info,=trace_abbrev,=trace_aranges]
           Displays the contents of the debug sections in the file, if any are
           present.  If one of the optional letters or words follows the
           switch then only data found in those specific sections will be
           dumped.

           Note that there is no single letter option to display the content
           of trace sections.

       -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, although the display format
           is different.  The format of the output depends upon the format of
           the file being dumped, but there are two main types.  One looks
           like this:

                   [  4](sec  3)(fl 0x00)(ty   0)(scl   3) (nx 1) 0x00000000 .bss
                   [  6](sec  1)(fl 0x00)(ty   0)(scl   2) (nx 0) 0x00000000 fred

           where the number inside the square brackets is the number of the
           entry in the symbol table, the sec number is the section number,
           the fl value are the symbol's flag bits, the ty number is the
           symbol's type, the scl number is the symbol's storage class and the
           nx value is the number of auxilary entries associated with the
           symbol.  The last two fields are the symbol's value and its name.

           The other common output format, usually seen with ELF based files,
           looks like this:

                   00000000 l    d  .bss   00000000 .bss
                   00000000 g       .text  00000000 fred

           Here the first number is the symbol's value (sometimes refered to
           as its address).  The next field is actually a set of characters
           and spaces indicating the flag bits that are set on the symbol.
           These characters are described below.  Next is the section with
           which the symbol is associated or *ABS* if the section is absolute
           (ie not connected with any section), or *UND* if the section is
           referenced in the file being dumped, but not defined there.

           After the section name comes another field, a number, which for
           common symbols is the alignment and for other symbol is the size.
           Finally the symbol's name is displayed.

           The flag characters are divided into 7 groups as follows:

           "l"
           "g"
           "u"
           "!" The symbol is a local (l), global (g), unique global (u),
               neither global nor local (a space) or both global and local
               (!).  A symbol can be neither local or global for a variety of
               reasons, e.g., because it is used for debugging, but it is
               probably an indication of a bug if it is ever both local and
               global.  Unique global symbols are a GNU extension to the
               standard set of ELF symbol bindings.  For such a symbol the
               dynamic linker will make sure that in the entire process there
               is just one symbol with this name and type in use.

           "w" The symbol is weak (w) or strong (a space).

           "C" The symbol denotes a constructor (C) or an ordinary symbol (a
               space).

           "W" The symbol is a warning (W) or a normal symbol (a space).  A
               warning symbol's name is a message to be displayed if the
               symbol following the warning symbol is ever referenced.

           "I"
           "i" The symbol is an indirect reference to another symbol (I), a
               function to be evaluated during reloc processing (i) or a
               normal symbol (a space).

           "d"
           "D" The symbol is a debugging symbol (d) or a dynamic symbol (D) or
               a normal symbol (a space).

           "F"
           "f"
           "O" The symbol is the name of a function (F) or a file (f) or an
               object (O) or just a normal symbol (a space).

       -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.

       --special-syms
           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.

       -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 -p -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.

       @file
           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
           removed.

           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.

SEE ALSO

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

COPYRIGHT

       Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
       2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 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 1.3 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".