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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]
	       [-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]
	       [-P options|--private=options]
	       [-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,=gdb_index]]
	       [-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,-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.

	   This option also has a subtle effect on the disassembly of
	   instructions in code sections.  When option -d is in effect objdump
	   will assume that any symbols present in a code section occur on the
	   boundary between instructions and it will refuse to disassemble
	   across such a boundary.  When option -D is in effect however this
	   assumption is supressed.  This means that it is possible for the
	   output of -d and -D to differ if, for example, data is stored in
	   code sections.

	   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.

       -P options
       --private=options
	   Print information that is specific to the object file format.  The
	   argument options is a comma separated list that depends on the
	   format (the lists of options is displayed with the help).

	   For XCOFF, the available options are: header, aout, sections, syms,
	   relocs, lineno, loader, except, typchk, traceback and toc.

       -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,=gdb_index]
	   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 or .gdb_index.

	   Note: the output from the =info option can also be affected by the
	   options --dwarf-depth, the --dwarf-start and the --dwarf-check.

       --dwarf-depth=n
	   Limit the dump of the ".debug_info" section to n children.  This is
	   only useful with --dwarf=info.  The default is to print all DIEs;
	   the special value 0 for n will also have this effect.

	   With a non-zero value for n, DIEs at or deeper than n levels will
	   not be printed.  The range for n is zero-based.

       --dwarf-start=n
	   Print only DIEs beginning with the DIE numbered n.  This is only
	   useful with --dwarf=info.

	   If specified, this option will suppress printing of any header
	   information and all DIEs before the DIE numbered n.	Only siblings
	   and children of the specified DIE will be printed.

	   This can be used in conjunction with --dwarf-depth.

       --dwarf-check
	   Enable additional checks for consistency of Dwarf information.

       -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) 1991-2013 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".



binutils-2.23.52.0.1		  2015-12-08			    OBJDUMP(1)