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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COPYRIGHT | COLOPHON |
OBJCOPY(1) GNU Development Tools OBJCOPY(1)
objcopy - copy and translate object files
objcopy [-F bfdname|--target=bfdname]
[-I bfdname|--input-target=bfdname]
[-O bfdname|--output-target=bfdname]
[-B bfdarch|--binary-architecture=bfdarch]
[-S|--strip-all]
[-g|--strip-debug]
[-K symbolname|--keep-symbol=symbolname]
[-N symbolname|--strip-symbol=symbolname]
[--strip-unneeded-symbol=symbolname]
[-G symbolname|--keep-global-symbol=symbolname]
[--localize-hidden]
[-L symbolname|--localize-symbol=symbolname]
[--globalize-symbol=symbolname]
[-W symbolname|--weaken-symbol=symbolname]
[-w|--wildcard]
[-x|--discard-all]
[-X|--discard-locals]
[-b byte|--byte=byte]
[-i [breadth]|--interleave[=breadth]]
[--interleave-width=width]
[-j sectionpattern|--only-section=sectionpattern]
[-R sectionpattern|--remove-section=sectionpattern]
[--remove-relocations=sectionpattern]
[-p|--preserve-dates]
[-D|--enable-deterministic-archives]
[-U|--disable-deterministic-archives]
[--debugging]
[--gap-fill=val]
[--pad-to=address]
[--set-start=val]
[--adjust-start=incr]
[--change-addresses=incr]
[--change-section-address sectionpattern{=,+,-}val]
[--change-section-lma sectionpattern{=,+,-}val]
[--change-section-vma sectionpattern{=,+,-}val]
[--change-warnings] [--no-change-warnings]
[--set-section-flags sectionpattern=flags]
[--add-section sectionname=filename]
[--dump-section sectionname=filename]
[--update-section sectionname=filename]
[--rename-section oldname=newname[,flags]]
[--long-section-names {enable,disable,keep}]
[--change-leading-char] [--remove-leading-char]
[--reverse-bytes=num]
[--srec-len=ival] [--srec-forceS3]
[--redefine-sym old=new]
[--redefine-syms=filename]
[--weaken]
[--keep-symbols=filename]
[--strip-symbols=filename]
[--strip-unneeded-symbols=filename]
[--keep-global-symbols=filename]
[--localize-symbols=filename]
[--globalize-symbols=filename]
[--weaken-symbols=filename]
[--add-symbol name=[section:]value[,flags]
[--alt-machine-code=index]
[--prefix-symbols=string]
[--prefix-sections=string]
[--prefix-alloc-sections=string]
[--add-gnu-debuglink=path-to-file]
[--keep-file-symbols]
[--only-keep-debug]
[--strip-dwo]
[--extract-dwo]
[--extract-symbol]
[--writable-text]
[--readonly-text]
[--pure]
[--impure]
[--file-alignment=num]
[--heap=size]
[--image-base=address]
[--section-alignment=num]
[--stack=size]
[--subsystem=which:major.minor]
[--compress-debug-sections]
[--decompress-debug-sections]
[--elf-stt-common=val]
[-v|--verbose]
[-V|--version]
[--help] [--info]
infile [outfile]
The GNU objcopy utility copies the contents of an object file to
another. objcopy uses the GNU BFD Library to read and write the
object files. It can write the destination object file in a format
different from that of the source object file. The exact behavior of
objcopy is controlled by command-line options. Note that objcopy
should be able to copy a fully linked file between any two formats.
However, copying a relocatable object file between any two formats
may not work as expected.
objcopy creates temporary files to do its translations and deletes
them afterward. objcopy uses BFD to do all its translation work; it
has access to all the formats described in BFD and thus is able to
recognize most formats without being told explicitly.
objcopy can be used to generate S-records by using an output target
of srec (e.g., use -O srec).
objcopy can be used to generate a raw binary file by using an output
target of binary (e.g., use -O binary). When objcopy generates a raw
binary file, it will essentially produce a memory dump of the
contents of the input object file. All symbols and relocation
information will be discarded. The memory dump will start at the
load address of the lowest section copied into the output file.
When generating an S-record or a raw binary file, it may be helpful
to use -S to remove sections containing debugging information. In
some cases -R will be useful to remove sections which contain
information that is not needed by the binary file.
Note---objcopy is not able to change the endianness of its input
files. If the input format has an endianness (some formats do not),
objcopy can only copy the inputs into file formats that have the same
endianness or which have no endianness (e.g., srec). (However, see
the --reverse-bytes option.)
infile
outfile
The input and output files, respectively. If you do not specify
outfile, objcopy creates a temporary file and destructively
renames the result with the name of infile.
-I bfdname
--input-target=bfdname
Consider the source file's object format to be bfdname, rather
than attempting to deduce it.
-O bfdname
--output-target=bfdname
Write the output file using the object format bfdname.
-F bfdname
--target=bfdname
Use bfdname as the object format for both the input and the
output file; i.e., simply transfer data from source to
destination with no translation.
-B bfdarch
--binary-architecture=bfdarch
Useful when transforming a architecture-less input file into an
object file. In this case the output architecture can be set to
bfdarch. This option will be ignored if the input file has a
known bfdarch. You can access this binary data inside a program
by referencing the special symbols that are created by the
conversion process. These symbols are called
_binary_objfile_start, _binary_objfile_end and
_binary_objfile_size. e.g. you can transform a picture file into
an object file and then access it in your code using these
symbols.
-j sectionpattern
--only-section=sectionpattern
Copy only the indicated sections from the input file to the
output file. This option may be given more than once. Note that
using this option inappropriately may make the output file
unusable. Wildcard characters are accepted in sectionpattern.
If the first character of sectionpattern is the exclamation point
(!) then matching sections will not be copied, even if earlier
use of --only-section on the same command line would otherwise
copy it. For example:
--only-section=.text.* --only-section=!.text.foo
will copy all sectinos maching '.text.*' but not the section
'.text.foo'.
-R sectionpattern
--remove-section=sectionpattern
Remove any section matching sectionpattern from the output file.
This option may be given more than once. Note that using this
option inappropriately may make the output file unusable.
Wildcard characters are accepted in sectionpattern. Using both
the -j and -R options together results in undefined behaviour.
If the first character of sectionpattern is the exclamation point
(!) then matching sections will not be removed even if an earlier
use of --remove-section on the same command line would otherwise
remove it. For example:
--remove-section=.text.* --remove-section=!.text.foo
will remove all sections matching the pattern '.text.*', but will
not remove the section '.text.foo'.
--remove-relocations=sectionpattern
Remove relocations from the output file for any section matching
sectionpattern. This option may be given more than once. Note
that using this option inappropriately may make the output file
unusable. Wildcard characters are accepted in sectionpattern.
For example:
--remove-relocations=.text.*
will remove the relocations for all sections matching the patter
'.text.*'.
If the first character of sectionpattern is the exclamation point
(!) then matching sections will not have their relocation removed
even if an earlier use of --remove-relocations on the same
command line would otherwise cause the relocations to be removed.
For example:
--remove-relocations=.text.* --remove-relocations=!.text.foo
will remove all relocations for sections matching the pattern
'.text.*', but will not remove relocations for the section
'.text.foo'.
-S
--strip-all
Do not copy relocation and symbol information from the source
file.
-g
--strip-debug
Do not copy debugging symbols or sections from the source file.
--strip-unneeded
Strip all symbols that are not needed for relocation processing.
-K symbolname
--keep-symbol=symbolname
When stripping symbols, keep symbol symbolname even if it would
normally be stripped. This option may be given more than once.
-N symbolname
--strip-symbol=symbolname
Do not copy symbol symbolname from the source file. This option
may be given more than once.
--strip-unneeded-symbol=symbolname
Do not copy symbol symbolname from the source file unless it is
needed by a relocation. This option may be given more than once.
-G symbolname
--keep-global-symbol=symbolname
Keep only symbol symbolname global. Make all other symbols local
to the file, so that they are not visible externally. This
option may be given more than once.
--localize-hidden
In an ELF object, mark all symbols that have hidden or internal
visibility as local. This option applies on top of symbol-
specific localization options such as -L.
-L symbolname
--localize-symbol=symbolname
Convert a global or weak symbol called symbolname into a local
symbol, so that it is not visible externally. This option may be
given more than once. Note - unique symbols are not converted.
-W symbolname
--weaken-symbol=symbolname
Make symbol symbolname weak. This option may be given more than
once.
--globalize-symbol=symbolname
Give symbol symbolname global scoping so that it is visible
outside of the file in which it is defined. This option may be
given more than once.
-w
--wildcard
Permit regular expressions in symbolnames used in other command
line options. The question mark (?), asterisk (*), backslash (\)
and square brackets ([]) operators can be used anywhere in the
symbol name. If the first character of the symbol name is the
exclamation point (!) then the sense of the switch is reversed
for that symbol. For example:
-w -W !foo -W fo*
would cause objcopy to weaken all symbols that start with "fo"
except for the symbol "foo".
-x
--discard-all
Do not copy non-global symbols from the source file.
-X
--discard-locals
Do not copy compiler-generated local symbols. (These usually
start with L or ..)
-b byte
--byte=byte
If interleaving has been enabled via the --interleave option then
start the range of bytes to keep at the byteth byte. byte can be
in the range from 0 to breadth-1, where breadth is the value
given by the --interleave option.
-i [breadth]
--interleave[=breadth]
Only copy a range out of every breadth bytes. (Header data is
not affected). Select which byte in the range begins the copy
with the --byte option. Select the width of the range with the
--interleave-width option.
This option is useful for creating files to program ROM. It is
typically used with an "srec" output target. Note that objcopy
will complain if you do not specify the --byte option as well.
The default interleave breadth is 4, so with --byte set to 0,
objcopy would copy the first byte out of every four bytes from
the input to the output.
--interleave-width=width
When used with the --interleave option, copy width bytes at a
time. The start of the range of bytes to be copied is set by the
--byte option, and the extent of the range is set with the
--interleave option.
The default value for this option is 1. The value of width plus
the byte value set by the --byte option must not exceed the
interleave breadth set by the --interleave option.
This option can be used to create images for two 16-bit flashes
interleaved in a 32-bit bus by passing -b 0 -i 4
--interleave-width=2 and -b 2 -i 4 --interleave-width=2 to two
objcopy commands. If the input was '12345678' then the outputs
would be '1256' and '3478' respectively.
-p
--preserve-dates
Set the access and modification dates of the output file to be
the same as those of the input file.
-D
--enable-deterministic-archives
Operate in deterministic mode. When copying archive members and
writing the archive index, use zero for UIDs, GIDs, timestamps,
and use consistent file modes for all files.
If binutils was configured with --enable-deterministic-archives,
then this mode is on by default. It can be disabled with the -U
option, below.
-U
--disable-deterministic-archives
Do not operate in deterministic mode. This is the inverse of the
-D option, above: when copying archive members and writing the
archive index, use their actual UID, GID, timestamp, and file
mode values.
This is the default unless binutils was configured with
--enable-deterministic-archives.
--debugging
Convert debugging information, if possible. This is not the
default because only certain debugging formats are supported, and
the conversion process can be time consuming.
--gap-fill val
Fill gaps between sections with val. This operation applies to
the load address (LMA) of the sections. It is done by increasing
the size of the section with the lower address, and filling in
the extra space created with val.
--pad-to address
Pad the output file up to the load address address. This is done
by increasing the size of the last section. The extra space is
filled in with the value specified by --gap-fill (default zero).
--set-start val
Set the start address of the new file to val. Not all object
file formats support setting the start address.
--change-start incr
--adjust-start incr
Change the start address by adding incr. Not all object file
formats support setting the start address.
--change-addresses incr
--adjust-vma incr
Change the VMA and LMA addresses of all sections, as well as the
start address, by adding incr. Some object file formats do not
permit section addresses to be changed arbitrarily. Note that
this does not relocate the sections; if the program expects
sections to be loaded at a certain address, and this option is
used to change the sections such that they are loaded at a
different address, the program may fail.
--change-section-address sectionpattern{=,+,-}val
--adjust-section-vma sectionpattern{=,+,-}val
Set or change both the VMA address and the LMA address of any
section matching sectionpattern. If = is used, the section
address is set to val. Otherwise, val is added to or subtracted
from the section address. See the comments under
--change-addresses, above. If sectionpattern does not match any
sections in the input file, a warning will be issued, unless
--no-change-warnings is used.
--change-section-lma sectionpattern{=,+,-}val
Set or change the LMA address of any sections matching
sectionpattern. The LMA address is the address where the section
will be loaded into memory at program load time. Normally this
is the same as the VMA address, which is the address of the
section at program run time, but on some systems, especially
those where a program is held in ROM, the two can be different.
If = is used, the section address is set to val. Otherwise, val
is added to or subtracted from the section address. See the
comments under --change-addresses, above. If sectionpattern does
not match any sections in the input file, a warning will be
issued, unless --no-change-warnings is used.
--change-section-vma sectionpattern{=,+,-}val
Set or change the VMA address of any section matching
sectionpattern. The VMA address is the address where the section
will be located once the program has started executing. Normally
this is the same as the LMA address, which is the address where
the section will be loaded into memory, but on some systems,
especially those where a program is held in ROM, the two can be
different. If = is used, the section address is set to val.
Otherwise, val is added to or subtracted from the section
address. See the comments under --change-addresses, above. If
sectionpattern does not match any sections in the input file, a
warning will be issued, unless --no-change-warnings is used.
--change-warnings
--adjust-warnings
If --change-section-address or --change-section-lma or
--change-section-vma is used, and the section pattern does not
match any sections, issue a warning. This is the default.
--no-change-warnings
--no-adjust-warnings
Do not issue a warning if --change-section-address or
--adjust-section-lma or --adjust-section-vma is used, even if the
section pattern does not match any sections.
--set-section-flags sectionpattern=flags
Set the flags for any sections matching sectionpattern. The
flags argument is a comma separated string of flag names. The
recognized names are alloc, contents, load, noload, readonly,
code, data, rom, share, and debug. You can set the contents flag
for a section which does not have contents, but it is not
meaningful to clear the contents flag of a section which does
have contents--just remove the section instead. Not all flags
are meaningful for all object file formats.
--add-section sectionname=filename
Add a new section named sectionname while copying the file. The
contents of the new section are taken from the file filename.
The size of the section will be the size of the file. This
option only works on file formats which can support sections with
arbitrary names. Note - it may be necessary to use the
--set-section-flags option to set the attributes of the newly
created section.
--dump-section sectionname=filename
Place the contents of section named sectionname into the file
filename, overwriting any contents that may have been there
previously. This option is the inverse of --add-section. This
option is similar to the --only-section option except that it
does not create a formatted file, it just dumps the contents as
raw binary data, without applying any relocations. The option
can be specified more than once.
--update-section sectionname=filename
Replace the existing contents of a section named sectionname with
the contents of file filename. The size of the section will be
adjusted to the size of the file. The section flags for
sectionname will be unchanged. For ELF format files the section
to segment mapping will also remain unchanged, something which is
not possible using --remove-section followed by --add-section.
The option can be specified more than once.
Note - it is possible to use --rename-section and
--update-section to both update and rename a section from one
command line. In this case, pass the original section name to
--update-section, and the original and new section names to
--rename-section.
--add-symbol name=[section:]value[,flags]
Add a new symbol named name while copying the file. This option
may be specified multiple times. If the section is given, the
symbol will be associated with and relative to that section,
otherwise it will be an ABS symbol. Specifying an undefined
section will result in a fatal error. There is no check for the
value, it will be taken as specified. Symbol flags can be
specified and not all flags will be meaningful for all object
file formats. By default, the symbol will be global. The
special flag 'before=othersym' will insert the new symbol in
front of the specified othersym, otherwise the symbol(s) will be
added at the end of the symbol table in the order they appear.
--rename-section oldname=newname[,flags]
Rename a section from oldname to newname, optionally changing the
section's flags to flags in the process. This has the advantage
over usng a linker script to perform the rename in that the
output stays as an object file and does not become a linked
executable.
This option is particularly helpful when the input format is
binary, since this will always create a section called .data. If
for example, you wanted instead to create a section called
.rodata containing binary data you could use the following
command line to achieve it:
objcopy -I binary -O <output_format> -B <architecture> \
--rename-section .data=.rodata,alloc,load,readonly,data,contents \
<input_binary_file> <output_object_file>
--long-section-names {enable,disable,keep}
Controls the handling of long section names when processing
"COFF" and "PE-COFF" object formats. The default behaviour,
keep, is to preserve long section names if any are present in the
input file. The enable and disable options forcibly enable or
disable the use of long section names in the output object; when
disable is in effect, any long section names in the input object
will be truncated. The enable option will only emit long section
names if any are present in the inputs; this is mostly the same
as keep, but it is left undefined whether the enable option might
force the creation of an empty string table in the output file.
--change-leading-char
Some object file formats use special characters at the start of
symbols. The most common such character is underscore, which
compilers often add before every symbol. This option tells
objcopy to change the leading character of every symbol when it
converts between object file formats. If the object file formats
use the same leading character, this option has no effect.
Otherwise, it will add a character, or remove a character, or
change a character, as appropriate.
--remove-leading-char
If the first character of a global symbol is a special symbol
leading character used by the object file format, remove the
character. The most common symbol leading character is
underscore. This option will remove a leading underscore from
all global symbols. This can be useful if you want to link
together objects of different file formats with different
conventions for symbol names. This is different from
--change-leading-char because it always changes the symbol name
when appropriate, regardless of the object file format of the
output file.
--reverse-bytes=num
Reverse the bytes in a section with output contents. A section
length must be evenly divisible by the value given in order for
the swap to be able to take place. Reversing takes place before
the interleaving is performed.
This option is used typically in generating ROM images for
problematic target systems. For example, on some target boards,
the 32-bit words fetched from 8-bit ROMs are re-assembled in
little-endian byte order regardless of the CPU byte order.
Depending on the programming model, the endianness of the ROM may
need to be modified.
Consider a simple file with a section containing the following
eight bytes: 12345678.
Using --reverse-bytes=2 for the above example, the bytes in the
output file would be ordered 21436587.
Using --reverse-bytes=4 for the above example, the bytes in the
output file would be ordered 43218765.
By using --reverse-bytes=2 for the above example, followed by
--reverse-bytes=4 on the output file, the bytes in the second
output file would be ordered 34127856.
--srec-len=ival
Meaningful only for srec output. Set the maximum length of the
Srecords being produced to ival. This length covers both
address, data and crc fields.
--srec-forceS3
Meaningful only for srec output. Avoid generation of S1/S2
records, creating S3-only record format.
--redefine-sym old=new
Change the name of a symbol old, to new. This can be useful when
one is trying link two things together for which you have no
source, and there are name collisions.
--redefine-syms=filename
Apply --redefine-sym to each symbol pair "old new" listed in the
file filename. filename is simply a flat file, with one symbol
pair per line. Line comments may be introduced by the hash
character. This option may be given more than once.
--weaken
Change all global symbols in the file to be weak. This can be
useful when building an object which will be linked against other
objects using the -R option to the linker. This option is only
effective when using an object file format which supports weak
symbols.
--keep-symbols=filename
Apply --keep-symbol option to each symbol listed in the file
filename. filename is simply a flat file, with one symbol name
per line. Line comments may be introduced by the hash character.
This option may be given more than once.
--strip-symbols=filename
Apply --strip-symbol option to each symbol listed in the file
filename. filename is simply a flat file, with one symbol name
per line. Line comments may be introduced by the hash character.
This option may be given more than once.
--strip-unneeded-symbols=filename
Apply --strip-unneeded-symbol option to each symbol listed in the
file filename. filename is simply a flat file, with one symbol
name per line. Line comments may be introduced by the hash
character. This option may be given more than once.
--keep-global-symbols=filename
Apply --keep-global-symbol option to each symbol listed in the
file filename. filename is simply a flat file, with one symbol
name per line. Line comments may be introduced by the hash
character. This option may be given more than once.
--localize-symbols=filename
Apply --localize-symbol option to each symbol listed in the file
filename. filename is simply a flat file, with one symbol name
per line. Line comments may be introduced by the hash character.
This option may be given more than once.
--globalize-symbols=filename
Apply --globalize-symbol option to each symbol listed in the file
filename. filename is simply a flat file, with one symbol name
per line. Line comments may be introduced by the hash character.
This option may be given more than once.
--weaken-symbols=filename
Apply --weaken-symbol option to each symbol listed in the file
filename. filename is simply a flat file, with one symbol name
per line. Line comments may be introduced by the hash character.
This option may be given more than once.
--alt-machine-code=index
If the output architecture has alternate machine codes, use the
indexth code instead of the default one. This is useful in case
a machine is assigned an official code and the tool-chain adopts
the new code, but other applications still depend on the original
code being used. For ELF based architectures if the index
alternative does not exist then the value is treated as an
absolute number to be stored in the e_machine field of the ELF
header.
--writable-text
Mark the output text as writable. This option isn't meaningful
for all object file formats.
--readonly-text
Make the output text write protected. This option isn't
meaningful for all object file formats.
--pure
Mark the output file as demand paged. This option isn't
meaningful for all object file formats.
--impure
Mark the output file as impure. This option isn't meaningful for
all object file formats.
--prefix-symbols=string
Prefix all symbols in the output file with string.
--prefix-sections=string
Prefix all section names in the output file with string.
--prefix-alloc-sections=string
Prefix all the names of all allocated sections in the output file
with string.
--add-gnu-debuglink=path-to-file
Creates a .gnu_debuglink section which contains a reference to
path-to-file and adds it to the output file. Note: the file at
path-to-file must exist. Part of the process of adding the
.gnu_debuglink section involves embedding a checksum of the
contents of the debug info file into the section.
If the debug info file is built in one location but it is going
to be installed at a later time into a different location then do
not use the path to the installed location. The
--add-gnu-debuglink option will fail because the installed file
does not exist yet. Instead put the debug info file in the
current directory and use the --add-gnu-debuglink option without
any directory components, like this:
objcopy --add-gnu-debuglink=foo.debug
At debug time the debugger will attempt to look for the separate
debug info file in a set of known locations. The exact set of
these locations varies depending upon the distribution being
used, but it typically includes:
"* The same directory as the executable."
"* A sub-directory of the directory containing the executable"
called .debug
"* A global debug directory such as /usr/lib/debug."
As long as the debug info file has been installed into one of
these locations before the debugger is run everything should work
correctly.
--keep-file-symbols
When stripping a file, perhaps with --strip-debug or
--strip-unneeded, retain any symbols specifying source file
names, which would otherwise get stripped.
--only-keep-debug
Strip a file, removing contents of any sections that would not be
stripped by --strip-debug and leaving the debugging sections
intact. In ELF files, this preserves all note sections in the
output.
Note - the section headers of the stripped sections are
preserved, including their sizes, but the contents of the section
are discarded. The section headers are preserved so that other
tools can match up the debuginfo file with the real executable,
even if that executable has been relocated to a different address
space.
The intention is that this option will be used in conjunction
with --add-gnu-debuglink to create a two part executable. One a
stripped binary which will occupy less space in RAM and in a
distribution and the second a debugging information file which is
only needed if debugging abilities are required. The suggested
procedure to create these files is as follows:
1.<Link the executable as normal. Assuming that is is called>
"foo" then...
1.<Run "objcopy --only-keep-debug foo foo.dbg" to>
create a file containing the debugging info.
1.<Run "objcopy --strip-debug foo" to create a>
stripped executable.
1.<Run "objcopy --add-gnu-debuglink=foo.dbg foo">
to add a link to the debugging info into the stripped
executable.
Note---the choice of ".dbg" as an extension for the debug info
file is arbitrary. Also the "--only-keep-debug" step is
optional. You could instead do this:
1.<Link the executable as normal.>
1.<Copy "foo" to "foo.full">
1.<Run "objcopy --strip-debug foo">
1.<Run "objcopy --add-gnu-debuglink=foo.full foo">
i.e., the file pointed to by the --add-gnu-debuglink can be the
full executable. It does not have to be a file created by the
--only-keep-debug switch.
Note---this switch is only intended for use on fully linked
files. It does not make sense to use it on object files where
the debugging information may be incomplete. Besides the
gnu_debuglink feature currently only supports the presence of one
filename containing debugging information, not multiple filenames
on a one-per-object-file basis.
--strip-dwo
Remove the contents of all DWARF .dwo sections, leaving the
remaining debugging sections and all symbols intact. This option
is intended for use by the compiler as part of the -gsplit-dwarf
option, which splits debug information between the .o file and a
separate .dwo file. The compiler generates all debug information
in the same file, then uses the --extract-dwo option to copy the
.dwo sections to the .dwo file, then the --strip-dwo option to
remove those sections from the original .o file.
--extract-dwo
Extract the contents of all DWARF .dwo sections. See the
--strip-dwo option for more information.
--file-alignment num
Specify the file alignment. Sections in the file will always
begin at file offsets which are multiples of this number. This
defaults to 512. [This option is specific to PE targets.]
--heap reserve
--heap reserve,commit
Specify the number of bytes of memory to reserve (and optionally
commit) to be used as heap for this program. [This option is
specific to PE targets.]
--image-base value
Use value as the base address of your program or dll. This is
the lowest memory location that will be used when your program or
dll is loaded. To reduce the need to relocate and improve
performance of your dlls, each should have a unique base address
and not overlap any other dlls. The default is 0x400000 for
executables, and 0x10000000 for dlls. [This option is specific
to PE targets.]
--section-alignment num
Sets the section alignment. Sections in memory will always begin
at addresses which are a multiple of this number. Defaults to
0x1000. [This option is specific to PE targets.]
--stack reserve
--stack reserve,commit
Specify the number of bytes of memory to reserve (and optionally
commit) to be used as stack for this program. [This option is
specific to PE targets.]
--subsystem which
--subsystem which:major
--subsystem which:major.minor
Specifies the subsystem under which your program will execute.
The legal values for which are "native", "windows", "console",
"posix", "efi-app", "efi-bsd", "efi-rtd", "sal-rtd", and "xbox".
You may optionally set the subsystem version also. Numeric
values are also accepted for which. [This option is specific to
PE targets.]
--extract-symbol
Keep the file's section flags and symbols but remove all section
data. Specifically, the option:
*<removes the contents of all sections;>
*<sets the size of every section to zero; and>
*<sets the file's start address to zero.>
This option is used to build a .sym file for a VxWorks kernel.
It can also be a useful way of reducing the size of a
--just-symbols linker input file.
--compress-debug-sections
Compress DWARF debug sections using zlib with SHF_COMPRESSED from
the ELF ABI. Note - if compression would actually make a section
larger, then it is not compressed.
--compress-debug-sections=none
--compress-debug-sections=zlib
--compress-debug-sections=zlib-gnu
--compress-debug-sections=zlib-gabi
For ELF files, these options control how DWARF debug sections are
compressed. --compress-debug-sections=none is equivalent to
--decompress-debug-sections. --compress-debug-sections=zlib and
--compress-debug-sections=zlib-gabi are equivalent to
--compress-debug-sections. --compress-debug-sections=zlib-gnu
compresses DWARF debug sections using zlib. The debug sections
are renamed to begin with .zdebug instead of .debug. Note - if
compression would actually make a section larger, then it is not
compressed nor renamed.
--decompress-debug-sections
Decompress DWARF debug sections using zlib. The original section
names of the compressed sections are restored.
--elf-stt-common=yes
--elf-stt-common=no
For ELF files, these options control whether common symbols
should be converted to the "STT_COMMON" or "STT_OBJECT" type.
--elf-stt-common=yes converts common symbol type to "STT_COMMON".
--elf-stt-common=no converts common symbol type to "STT_OBJECT".
-V
--version
Show the version number of objcopy.
-v
--verbose
Verbose output: list all object files modified. In the case of
archives, objcopy -V lists all members of the archive.
--help
Show a summary of the options to objcopy.
--info
Display a list showing all architectures and object formats
available.
@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.
ld(1), objdump(1), and the Info entries for binutils.
Copyright (c) 1991-2017 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".
This page is part of the binutils (a collection of tools for working
with executable binaries) project. Information about the project can
be found at ⟨http://www.gnu.org/software/binutils/⟩. If you have a
bug report for this manual page, see
⟨http://sourceware.org/bugzilla/enter_bug.cgi?product=binutils⟩. This
page was obtained from the tarball binutils-2.28.tar.gz fetched from
⟨https://ftp.gnu.org/gnu/binutils/⟩ on 2017-07-05. If you discover
any rendering problems in this HTML version of the page, or you
believe there is a better or more up-to-date source for the page, or
you have corrections or improvements to the information in this
COLOPHON (which is not part of the original manual page), send a mail
to man-pages@man7.org
binutils-2.28 2017-03-02 OBJCOPY(1)