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objdump - phpMan objdump - phpMan

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File: binutils.info,  Node: objdump,  Next: ranlib,  Prev: objcopy,  Up: Top

4 objdump
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     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[lLiaprmfFsoR]'|
              `--dwarf'[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]]
             [`-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...

   `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.

`-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.  *Note Target Selection::,
     for more information.

`-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. *Note c++filt::, for more information on demangling.

`-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[lLiaprmfFsoR]'
`--dwarf[=rawline,=decodedline,=info,=abbrev,=pubnames,=aranges,=macro,=frames,=frames-interp,=str,=loc,=Ranges]'
     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.

`-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.  For more information on stabs symbols, see
     *note Stabs: (stabs.info)Top.

`--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.