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OBJCOPY(1)		     GNU Development Tools		    OBJCOPY(1)



NAME
       objcopy - copy and translate object files

SYNOPSIS
       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]
	       [-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]

DESCRIPTION
       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.)

OPTIONS
       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.

       -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.

       -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
	   Make symbol symbolname local to the file, so that it is not visible
	   externally.	This option may be given more than once.

       -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.

SEE ALSO
       ld(1), objdump(1), and the Info entries for binutils.

COPYRIGHT
       Copyright (c) 1991-2016 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-2.27			  2016-08-03			    OBJCOPY(1)