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NetBSD 6.1.5 - man page for objdump (netbsd section 1)

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

	   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 compiler.

	   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.

	   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.

	   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

	   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.

	   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.

	   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.

	   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.

	   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

       -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.

	   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
	   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:

	       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

	       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

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

	   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.

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

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

	   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.

	   Display width bytes on a single line when disassembling instructions.

	   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

	   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, 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:

	   "!" 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

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

	   "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).

	   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 displayed.

	   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 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.

       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, 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".

binutils-2.21.1 			    2011-06-27				       OBJDUMP(1)

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