Provided by: binutils-djgpp_2.35.1+dfsg-2_amd64 bug

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]
               [--strip-unneeded]
               [-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]
               [--globalize-symbols=filename]
               [-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]
               [--keep-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]
               [--set-section-alignment sectionpattern=align]
               [--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]
               [--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]
               [--merge-notes]
               [--no-merge-notes]
               [--verilog-data-width=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.

           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 matching '.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'.

       --keep-section=sectionpattern
           When removing sections from the output file, keep sections that match sectionpattern.

       --remove-relocations=sectionpattern
           Remove non-dynamic 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, and attempting to remove a dynamic
           relocation section such as .rela.plt from an executable or shared library with
           --remove-relocations=.plt will not work.  Wildcard characters are accepted in
           sectionpattern.  For example:

                     --remove-relocations=.text.*

           will remove the relocations for all sections matching the pattern '.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.  Note: this
           option cannot be used in conjunction with the --globalize-symbol or
           --globalize-symbols options.

       --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.  Note: this option
           cannot be used in conjunction with the -G or --keep-global-symbol options.

       -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 (also known as the entry 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 (also known as the entry 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, exclude, 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.  In particular the
           share flag is only meaningful for COFF format files and not for ELF format files.

       --set-section-alignment sectionpattern=align
           Set the alignment for any sections matching sectionpattern.  align specifies the
           alignment in bytes and must be a power of two, i.e. 1, 2, 4, 8....

       --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 using 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 accepts the same set of flags as the --sect-section-flags
           option.

           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.  Note: this option
           cannot be used in conjunction with the -G or --keep-global-symbol options.

       --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 it 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 field in the PE header.  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".

       --merge-notes
       --no-merge-notes
           For ELF files, attempt (or do not attempt) to reduce the size of any SHT_NOTE type
           sections by removing duplicate notes.

       -V
       --version
           Show the version number of objcopy.

       --verilog-data-width=bytes
           For Verilog output, this options controls the number of bytes converted for each
           output data element.  The input target controls the endianness of the conversion.

       -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) 1991-2020 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".