Provided by: llvm-14_14.0.0-1ubuntu1.1_amd64 bug

NAME

       llvm-objcopy - object copying and editing tool

SYNOPSIS

       llvm-objcopy [options] input [output]

DESCRIPTION

       llvm-objcopy is a tool to copy and manipulate objects. In basic usage, it makes a semantic
       copy of the input to the output. If any options are specified, the output may be  modified
       along the way, e.g. by removing sections.

       If  no  output file is specified, the input file is modified in-place. If “-” is specified
       for the input file, the input is read from the program’s standard input stream. If “-”  is
       specified  for the output file, the output is written to the standard output stream of the
       program.

       If the input is an archive, any requested operations  will  be  applied  to  each  archive
       member individually.

       The  tool  is  still  in  active  development, but in most scenarios it works as a drop-in
       replacement for GNU’s objcopy.

GENERIC AND CROSS-PLATFORM OPTIONS

       The following options are either agnostic of the file format, or apply  to  multiple  file
       formats.

       --add-gnu-debuglink <debug-file>
              Add a .gnu_debuglink section for <debug-file> to the output.

       --add-section <section=file>
              Add  a  section  named <section> with the contents of <file> to the output. For ELF
              objects the section will be of type SHT_NOTE, if  the  name  starts  with  “.note”.
              Otherwise,  it  will have type SHT_PROGBITS. Can be specified multiple times to add
              multiple sections.

              For MachO objects, <section> must be formatted as <segment name>,<section name>.

       --binary-architecture <arch>, -B
              Ignored for compatibility.

       --disable-deterministic-archives, -U
              Use real values for UIDs, GIDs and timestamps when updating archive member headers.

       --discard-all, -x
              Remove most local symbols from the output. Different file formats may limit this to
              a subset of the local symbols. For example, file and section symbols in ELF objects
              will not be discarded. Additionally, remove all debug sections.

       --dump-section <section>=<file>
              Dump the contents of section <section> into  the  file  <file>.  Can  be  specified
              multiple  times  to dump multiple sections to different files.  <file> is unrelated
              to the input and output files provided to  llvm-objcopy  and  as  such  the  normal
              copying and editing operations will still be performed. No operations are performed
              on the sections prior to dumping them.

              For MachO objects, <section> must be formatted as <segment name>,<section name>.

       --enable-deterministic-archives, -D
              Enable deterministic mode when copying archives, i.e.  use  0  for  archive  member
              header UIDs, GIDs and timestamp fields. On by default.

       --help, -h
              Print a summary of command line options.

       --only-keep-debug
              Produce  a debug file as the output that only preserves contents of sections useful
              for debugging purposes.

              For ELF objects, this removes the contents  of  SHF_ALLOC  sections  that  are  not
              SHT_NOTE  by  making  them  SHT_NOBITS  and  shrinking  the  program  headers where
              possible.

       --only-section <section>, -j
              Remove all sections from the output, except for sections named <section>.   Can  be
              specified multiple times to keep multiple sections.

              For MachO objects, <section> must be formatted as <segment name>,<section name>.

       --redefine-sym <old>=<new>
              Rename symbols called <old> to <new> in the output. Can be specified multiple times
              to rename multiple symbols.

       --redefine-syms <filename>
              Rename symbols in the output as described in the file <filename>. In the file, each
              line represents a single symbol to rename, with the old name and new name separated
              by whitespace. Leading and trailing whitespace is ignored, as is anything following
              a ‘#’. Can be specified multiple times to read names from multiple files.

       --regex
              If  specified,  symbol and section names specified by other switches are treated as
              extended POSIX regular expression patterns.

       --remove-section <section>, -R
              Remove the specified section from the output. Can be specified  multiple  times  to
              remove multiple sections simultaneously.

              For MachO objects, <section> must be formatted as <segment name>,<section name>.

       --set-section-alignment <section>=<align>
              Set the alignment of section <section> to <align>`. Can be specified multiple times
              to update multiple sections.

       --set-section-flags <section>=<flag>[,<flag>,...]
              Set section properties in the output of section <section> based  on  the  specified
              <flag> values. Can be specified multiple times to update multiple sections.

              Supported flag names are alloc, load, noload, readonly, exclude, debug, code, data,
              rom, share, contents, merge and strings. Not  all  flags  are  meaningful  for  all
              object file formats.

              For ELF objects, the flags have the following effects:

              • alloc = add the SHF_ALLOC flag.

              • load = if the section has SHT_NOBITS type, mark it as a SHT_PROGBITS section.

              • readonly = if this flag is not specified, add the SHF_WRITE flag.

              • exclude = add the SHF_EXCLUDE flag.

              • code = add the SHF_EXECINSTR flag.

              • merge = add the SHF_MERGE flag.

              • strings = add the SHF_STRINGS flag.

              • contents = if the section has SHT_NOBITS type, mark it as a SHT_PROGBITS section.

              For COFF objects, the flags have the following effects:

              • alloc  =  add  the IMAGE_SCN_CNT_UNINITIALIZED_DATA and IMAGE_SCN_MEM_READ flags,
                unless the load flag is specified.

              • noload = add the IMAGE_SCN_LNK_REMOVE and IMAGE_SCN_MEM_READ flags.

              • readonly = if this flag is not specified, add the IMAGE_SCN_MEM_WRITE flag.

              • exclude = add the IMAGE_SCN_LNK_REMOVE and IMAGE_SCN_MEM_READ flags.

              • debug = add  the  IMAGE_SCN_CNT_INITIALIZED_DATA,  IMAGE_SCN_MEM_DISCARDABLE  and
                IMAGE_SCN_MEM_READ flags.

              • code  =  add the IMAGE_SCN_CNT_CODE, IMAGE_SCN_MEM_EXECUTE and IMAGE_SCN_MEM_READ
                flags.

              • data = add the IMAGE_SCN_CNT_INITIALIZED_DATA and IMAGE_SCN_MEM_READ flags.

              • share = add the IMAGE_SCN_MEM_SHARED and IMAGE_SCN_MEM_READ flags.

       --strip-all-gnu
              Remove all symbols, debug sections and relocations from the output. This option  is
              equivalent to GNU objcopy’s --strip-all switch.

       --strip-all, -S
              For  ELF  objects,  remove  from  the output all symbols and non-alloc sections not
              within segments, except for .gnu.warning, .ARM.attribute sections and  the  section
              name table.

              For  COFF  and  Mach-O objects, remove all symbols, debug sections, and relocations
              from the output.

       --strip-debug, -g
              Remove all debug sections from the output.

       --strip-symbol <symbol>, -N
              Remove all symbols named <symbol> from the output. Can be specified multiple  times
              to remove multiple symbols.

       --strip-symbols <filename>
              Remove  all  symbols whose names appear in the file <filename>, from the output. In
              the file, each line represents a single symbol  name,  with  leading  and  trailing
              whitespace ignored, as is anything following a ‘#’. Can be specified multiple times
              to read names from multiple files.

       --strip-unneeded-symbol <symbol>
              Remove from the output all symbols named <symbol> that are local or  undefined  and
              are not required by any relocation.

       --strip-unneeded-symbols <filename>
              Remove  all  symbols whose names appear in the file <filename>, from the output, if
              they are local or undefined and are not required by any relocation.  In  the  file,
              each  line  represents  a  single symbol name, with leading and trailing whitespace
              ignored, as is anything following a ‘#’. Can be specified multiple  times  to  read
              names from multiple files.

       --strip-unneeded
              Remove  from  the  output  all  local or undefined symbols that are not required by
              relocations. Also remove all debug sections.

       --version, -V
              Display the version of the llvm-objcopy executable.

       --wildcard, -w
              Allow wildcard syntax for symbol-related flags. On by default  for  section-related
              flags. Incompatible with –regex.

              Wildcard syntax allows the following special symbols:

                           ┌───────────────┬──────────────────────────┬────────────┐
                           │Character      │ Meaning                  │ Equivalent │
                           ├───────────────┼──────────────────────────┼────────────┤
                           │*              │ Any number of characters │ .*         │
                           ├───────────────┼──────────────────────────┼────────────┤
                           │?              │ Any single character     │ .          │
                           ├───────────────┼──────────────────────────┼────────────┤
                           │\              │ Escape      the     next │ \          │
                           │               │ character                │            │
                           ├───────────────┼──────────────────────────┼────────────┤
                           │[a-z]          │ Character class          │ [a-z]      │
                           ├───────────────┼──────────────────────────┼────────────┤
                           │[!a-z], [^a-z] │ Negated character class  │ [^a-z]     │
                           └───────────────┴──────────────────────────┴────────────┘

              Additionally, starting a wildcard with ‘!’ will prevent a match,  even  if  another
              flag matches. For example -w -N '*' -N '!x' will strip all symbols except for x.

              The  order of wildcards does not matter. For example, -w -N '*' -N '!x' is the same
              as -w -N '!x' -N '*'.

       @<FILE>
              Read command-line options and commands from response file <FILE>.

ELF-SPECIFIC OPTIONS

       The following options are implemented only for ELF objects. If used  with  other  objects,
       llvm-objcopy will either emit an error or silently ignore them.

       --add-symbol <name>=[<section>:]<value>[,<flags>]
              Add  a  new  symbol  called <name> to the output symbol table, in the section named
              <section>, with value <value>. If <section> is not specified, the symbol  is  added
              as  an  absolute  symbol. The <flags> affect the symbol properties. Accepted values
              are:

              • global = the symbol will have global binding.

              • local = the symbol will have local binding.

              • weak = the symbol will have weak binding.

              • default = the symbol will have default visibility.

              • hidden = the symbol will have hidden visibility.

              • protected = the symbol will have protected visibility.

              • file = the symbol will be an STT_FILE symbol.

              • section = the symbol will be an STT_SECTION symbol.

              • object = the symbol will be an STT_OBJECT symbol.

              • function = the symbol will be an STT_FUNC symbol.

              • indirect-function = the symbol will be an STT_GNU_IFUNC symbol.

              Additionally, the following flags are accepted  but  ignored:  debug,  constructor,
              warning, indirect, synthetic, unique-object, before.

              Can be specified multiple times to add multiple symbols.

       --allow-broken-links
              Allow  llvm-objcopy  to  remove  sections  even  if  it would leave invalid section
              references. Any invalid sh_link fields will be set to zero.

       --change-start <incr>, --adjust-start
              Add <incr> to the program’s start address. Can  be  specified  multiple  times,  in
              which case the values will be applied cumulatively.

       --compress-debug-sections [<style>]
              Compress  DWARF debug sections in the output, using the specified style.  Supported
              styles are zlib-gnu and zlib. Defaults to zlib if no style is specified.

       --decompress-debug-sections
              Decompress any compressed DWARF debug sections in the output.

       --discard-locals, -X
              Remove local symbols starting with “.L” from the output.

       --extract-dwo
              Remove all sections that are not DWARF .dwo sections from the output.

       --extract-main-partition
              Extract the main partition from the output.

       --extract-partition <name>
              Extract the named partition from the output.

       --globalize-symbol <symbol>
              Mark any defined symbols named <symbol> as global symbols in the  output.   Can  be
              specified multiple times to mark multiple symbols.

       --globalize-symbols <filename>
              Read  a  list of names from the file <filename> and mark defined symbols with those
              names as global in the output. In the file, each line represents a  single  symbol,
              with  leading  and trailing whitespace ignored, as is anything following a ‘#’. Can
              be specified multiple times to read names from multiple files.

       --input-target <format>, -I
              Read the input as the specified format. See SUPPORTED FORMATS for a list  of  valid
              <format>  values. If unspecified, llvm-objcopy will attempt to determine the format
              automatically.

       --keep-file-symbols
              Keep symbols of type STT_FILE, even if they would otherwise be stripped.

       --keep-global-symbol <symbol>, -G
              Make all symbols local in the output, except for symbols with  the  name  <symbol>.
              Can be specified multiple times to ignore multiple symbols.

       --keep-global-symbols <filename>
              Make  all  symbols  local  in  the  output,  except  for  symbols named in the file
              <filename>. In the file, each line represents a single  symbol,  with  leading  and
              trailing  whitespace  ignored,  as  is  anything  following a ‘#’. Can be specified
              multiple times to read names from multiple files.

       --keep-section <section>
              When removing sections from the output, do not remove sections named <section>. Can
              be specified multiple times to keep multiple sections.

       --keep-symbol <symbol>, -K
              When removing symbols from the output, do not remove symbols named <symbol>. Can be
              specified multiple times to keep multiple symbols.

       --keep-symbols <filename>
              When removing symbols from the output do not  remove  symbols  named  in  the  file
              <filename>.  In  the  file,  each line represents a single symbol, with leading and
              trailing whitespace ignored, as is anything  following  a  ‘#’.  Can  be  specified
              multiple times to read names from multiple files.

       --localize-hidden
              Make all symbols with hidden or internal visibility local in the output.

       --localize-symbol <symbol>, -L
              Mark  any defined non-common symbol named <symbol> as a local symbol in the output.
              Can be specified multiple times to mark multiple symbols as local.

       --localize-symbols <filename>
              Read a list of names from the file <filename> and mark defined  non-common  symbols
              with those names as local in the output. In the file, each line represents a single
              symbol, with leading and trailing whitespace ignored, as is  anything  following  a
              ‘#’. Can be specified multiple times to read names from multiple files.

       --new-symbol-visibility <visibility>
              Specify the visibility of the symbols automatically created when using binary input
              or --add-symbol. Valid options are:

              • defaulthiddeninternalprotected

              The default is default.

       --output-target <format>, -O
              Write the output as the specified format. See SUPPORTED FORMATS for a list of valid
              <format> values. If unspecified, the output format is assumed to be the same as the
              value specified for --input-target or the input file’s format  if  that  option  is
              also unspecified.

       --prefix-alloc-sections <prefix>
              Add <prefix> to the front of the names of all allocatable sections in the output.

       --prefix-symbols <prefix>
              Add <prefix> to the front of every symbol name in the output.

       --preserve-dates, -p
              Preserve access and modification timestamps in the output.

       --rename-section <old>=<new>[,<flag>,...]
              Rename sections called <old> to <new> in the output, and apply any specified <flag>
              values. See --set-section-flags for a list of supported  flags.  Can  be  specified
              multiple times to rename multiple sections.

       --set-start-addr <addr>
              Set  the  start address of the output to <addr>. Overrides any previously specified
              --change-start or --adjust-start options.

       --split-dwo <dwo-file>
              Equivalent to running llvm-objcopy with --extract-dwo and <dwo-file> as the  output
              file and no other options, and then with --strip-dwo on the input file.

       --strip-dwo
              Remove all DWARF .dwo sections from the output.

       --strip-non-alloc
              Remove from the output all non-allocatable sections that are not within segments.

       --strip-sections
              Remove  from  the  output  all  section  headers  and  all  section data not within
              segments. Note that many tools will not be able to use an  object  without  section
              headers.

       --target <format>, -F
              Equivalent  to  --input-target  and  --output-target  for the specified format. See
              SUPPORTED FORMATS for a list of valid <format> values.

       --weaken-symbol <symbol>, -W
              Mark any global symbol named <symbol> as a  weak  symbol  in  the  output.  Can  be
              specified multiple times to mark multiple symbols as weak.

       --weaken-symbols <filename>
              Read  a  list  of names from the file <filename> and mark global symbols with those
              names as weak in the output. In the file, each line  represents  a  single  symbol,
              with  leading  and trailing whitespace ignored, as is anything following a ‘#’. Can
              be specified multiple times to read names from multiple files.

       --weaken
              Mark all defined global symbols as weak in the output.

MACH-O-SPECIFIC OPTIONS

       --keep-undefined
              Keep undefined symbols, even if they would otherwise be stripped.

COFF-SPECIFIC OPTIONS

       --subsystem <name>[:<version>]
              Set the PE subsystem, and optionally subsystem version.

SUPPORTED FORMATS

       The following values are currently  supported  by  llvm-objcopy  for  the  --input-target,
       --output-target,  and  --target options. For GNU objcopy compatibility, the values are all
       bfdnames.

       • binaryihexelf32-i386elf32-x86-64elf64-x86-64elf32-iamcuelf32-littlearmelf64-aarch64elf64-littleaarch64elf32-littleriscvelf64-littleriscvelf32-powerpcelf32-powerpcleelf64-powerpcelf64-powerpcleelf32-bigmipself32-ntradbigmipself32-ntradlittlemipself32-tradbigmipself32-tradlittlemipself64-tradbigmipself64-tradlittlemipself32-sparcelf32-sparcel

       Additionally, all targets except binary and ihex can have -freebsd as a suffix.

BINARY INPUT AND OUTPUT

       If binary is used as the value for --input-target, the input file will be  embedded  as  a
       data  section  in  an  ELF  relocatable  object,  with  symbols _binary_<file_name>_start,
       _binary_<file_name>_end, and _binary_<file_name>_size representing the start, end and size
       of  the  data, where <file_name> is the path of the input file as specified on the command
       line with non-alphanumeric characters converted to _.

       If binary is used as the value for --output-target, the output file will be a  raw  binary
       file,  containing  the memory image of the input file.  Symbols and relocation information
       will be discarded. The image will start at the address of the first  loadable  section  in
       the output.

EXIT STATUS

       llvm-objcopy  exits  with  a non-zero exit code if there is an error.  Otherwise, it exits
       with code 0.

BUGS

       To            report             bugs,             please             visit             <‐
       https://github.com/llvm/llvm-project/labels/tools:llvm-objcopy/strip/>.

       There  is  a  known  issue  with  --input-target and --target causing only binary and ihex
       formats to have any effect. Other values will be ignored and llvm-objcopy will attempt  to
       guess the input format.

SEE ALSO

       llvm-strip(1)

AUTHOR

       Maintained by the LLVM Team (https://llvm.org/).

COPYRIGHT

       2003-2023, LLVM Project