objcopy(1) - copy and translate object files



  • 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]
    	       [--dwarf-depth=n]
    	       [--dwarf-start=n]
    	       [-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.
    
           -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) 1991-2015 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-2.26.1 		  2016-06-29			    OBJCOPY(1)
    


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