objdump - Unix, Linux Command

objfile... are the object files to be examined.  When you
specify archives, objdump shows information on each of the member
object files.



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.



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.



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.  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.  e300 selects
disassembly for the e300 family.



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:




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.



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.


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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.