ld —
link
editor
| ld |
[-(]
[-)]
[-Bdynamic]
[-Bshareable]
[-Bstatic]
[-I
file |
--dynamic-linker=file]
[-L
dir |
--library-path=dir]
[-M |
--print-map]
[-T
script-file |
--script=script-file]
[-V |
-v |
--version]
[-a
linkmode]
[-b
input-format |
--format=input-format]
[-call_shared]
[-d |
-dc |
-dp]
[-dn]
[-dy]
[-e
symbol |
--entry=symbol]
[-h
name |
-soname=name]
[-l
library |
--library=library]
[-o
output-file |
--output=output-file]
[-q |
--emit-relocs]
[-r |
--relocatable]
[-u
name |
--undefined=name]
[-z
keyword]
[--as-needed]
[--eh-frame-hdr]
[--end-group]
[--gc-sections]
[--no-as-needed]
[--no-define-common]
[--no-gc-sections]
[--no-print-gc-sections]
[--no-whole-archive]
[--oformat=format]
[--pic-executable |
-pie]
[--print-gc-sections]
[--rpath=dirs]
[--rpath-link=dirs]
[--start-group]
[-shared]
[-static]
[--version-script=script]
[--whole-archive]
file ... |
The
ld utility combines ELF objects and
ar(1) archives containing ELF
objects into an executable or a partially relocated object.
The
ld utility processes options and files in the
order presented on the command line. Unlike most
UNIX
utilities, options and file names may be interspersed. Options seen on the
command line will generally apply to subsequent files, or till overridden by
another option.
The
ld utility supports the following options:
-
-
- -(
archives...
-)
- Start a group of archives that are to be searched
repeatedly until no new undefined references are created. This option is
used when there are circular references between one or more archives in
the archive group.
The files named by the arguments archives
are expected to be archive files.
Each use of the -( option starts a new archive
group that is ended by a matching -)
option.
-
-
- -Bdynamic
- Choose dynamic libraries for the libraries specified by
subsequent -l options.
-
-
- -Bshareable
- Create a shared library.
-
-
- -Bstatic
- Choose static libraries for the libraries specified by
subsequent -l options.
-
-
- -I
file |
--dynamic-linker=file
- Set the name of the dynamic linker when generating ELF
executables.
-
-
- -L
dir |
--library-path=dir
- Add directory dir to the
list of paths that ld will search for archive
libraries. This option may be specified multiple times. User supplied
directories are searched in the order specified on the command line.
-
-
- -M
|
--print-map
- Print a link map to standard output.
-
-
- -T
script-file |
--script=script-file
- Use the file name by argument
script-file as the linker script instead
of the default.
-
-
- -V
| -v |
-version
- Print a version identifier for
ld and exit.
-
-
- -a
linkmode
- Select linking mode. The value of the argument
linkmode should be one of the following
literals:
- default
- Equivalent to specifying
-Bdynamic.
- archive
- Equivalent to specifying
-Bstatic.
- shared
- Equivalent to specifying
-Bdynamic.
-
-
- -b
input-format |
--format
input-format
- Set the input format to that specified by argument
input-format. The legal values for the
argument input-format are those supported
by
elftc_bfd_find_target(3).
-
-
- -d
|
-dc
|
-dp
- Assign space for common symbols even if generating a
relocatable object.
-
-
- -dn
- Equivalent to specifying option
-Bstatic.
-
-
- -dy
- Equivalent to specifying option
-Bdynamic.
-
-
- -e
entry |
--entry
entry
- Set execution to start at the symbol named by the argument
entry. The argument should be the name of
a symbol.
-
-
- -h
name |
-soname
name
- Set the
DT_SONAME field in the
object to that specified by the argument
name.
-
-
- -l
name |
--library=name
- Add the archive library or shared library named by argument
name to the set of files to link. This
file is looked for in the list of directories specified by prior
-L options on the command line.
-
-
- -o
output-file |
--output=output-file
- Use the file specified by argument
output-file for the output, instead of
the default file name of ‘a.out’.
-
-
- -q
|
--emit-relocs
- Preserve relocation information in executables, for use by
post-link analysis tools.
-
-
- -r
|
--relocatable
- Generate a relocatable output file that can be used as
input for subsequent linker runs.
-
-
- -u
name |
--undefined=name
- Add the symbol specified by argument
name to the output file as an undefined
symbol. This option may be specified multiple times.
-
-
- -z
keyword
- Recognized keywords include:
- execstack
- Require the object to use an executable stack.
- noexecstack
- Do not require the object to use an executable
stack.
-
-
- --as-needed
- Add
DT_NEEDED tags for only those
shared libraries that satisfy non-weak unresolved references from object
files or other dynamic libraries seen so far on the command line.
-
-
- -call_shared
- Equivalent to specifying option
-Bdynamic.
-
-
- --eh-frame-hdr
- Create a “.eh_frame_hdr” section, and a
PT_GNU_EH_FRAME segment header, containing
exception handling information.
-
-
- --end-group
- Equivalent to specifying option
-).
-
-
- --gc-sections
- Garbage collect unused input sections.
-
-
- --no-as-needed
- Insert
DT_NEEDED tags for all
shared libraries seen henceforth on the command line, irrespective of
whether the shared library is needed to resolve an undefined symbol or
not. This behavior is the default.
-
-
- --no-define-common
- Do not assign addresses to common symbols.
-
-
- --no-gc-sections
- Do not garbage collect input sections that contain
unreferenced symbols.
-
-
- --no-print-gc-sections
- Do not print the list of sections removed when the
--gc-sections directive is active.
-
-
- --no-whole-archive
- Only include objects in an archive that satisfy an
unresolved reference in the link. This behavior is the default.
-
-
- -non_shared
- Equivalent to specifying option
-Bstatic.
-
-
- --oformat=format
- Set the desired output format to that specified by the
argument format. Supported values for
argument format are those understood by
elftc_bfd_find_target(3).
-
-
- --pic-executable
|
-pie
- Create a position-independent executable.
-
-
- --print-gc-sections
- Print the list of sections removed when the
--gc-sections directive is active. The output
is printed to stderr.
-
-
- --rpath=dirs
- Add the colon-separated list of directories named by the
argument dirs to the runtime library
search path and to the link-time search path.
-
-
- --rpath-link=dirs
- Add the directories specified by the colon-separated list
of directories in argument dirs to the
link-time search path for libraries. The directories specified by this
option are searched before those specified by
--rpath options.
-
-
- -shared
- Equivalent to specifying option
-Bshareable.
-
-
- --start-group
- Equivalent to specifying option
-(.
-
-
- -static
- Equivalent to specifying option
-Bstatic.
-
-
- --version-script=script-file
- Use the version script in the file named by argument
script-file.
-
-
- --whole-archive
- Include the entire contents of every archive file
encountered on the command line after this option in the link.
The
ld utility exits 0 on success,
and >0 if an error occurs.
ar(1),
ranlib(1),
archive(3),
elf(3),
elftc_bfd_find_target(3),
dwarf(3)
The
ld utility differs from its GNU equivalent in
the following:
- The ld utility currently
supports a limited range of output formats.
- The -e and
--entry options only accept a symbol name as
an argument, and not a numeric address.
- The -l option only searches
files in the directories specified by prior
-L options.
- The -T |
--script
option does not search for script files in the directories specified by
prior -L options.
- The --rpath option accepts
a colon-separated list of directories instead of single directory.
The following options are recognized, but are currently unimplemented:
-Bgroup,
-Bsymbolic,
-Bsymbolic_functions,
-E,
-EB,
-EL,
-F,
-Map,
-N,
-O,
-Qy,
-R,
-S,
-Tbss,
-Tdata,
-Ttext,
-X,
-Y,
-Ur,
-c,
-f,
-g,
-i,
-m,
-n,
-s,
-t,
-x,
-y,
--accept-unknown-input-arch,
--allow-multiple-definition,
--allow-shlib-undefined,
--assert,
--auxiliary,
--build-id,
--check-sections,
--cref,
--defsym,
--demangle,
--disable-new-dtags,
--discard-all,
--discard-locals,
--error-unresolved-symbols,
--export-dynamic,
--emulation,
--enable-new-dtags,
--fatal-warnings,
--filter,
--fini,
--hash-style,
--help,
--init,
--just-symbols,
--mri-script,
--nmagic,
-nostdlib,
--no-accept-unknown-input-arch,
--no-allow-shlib-undefined,
--no-assert,
--no-check-sections,
--no-demangle,
--no-keep-memory,
--no-omagic,
--no-undefined,
--no-undefined-version,
--no-warn-mismatch,
--omagic,
--qmagic,
--relax,
--retain-symbols-file,
--runpath,
--section-start,
--sort-common,
--split-by-file,
--split-by-reloc,
--stats,
--strip-all,
--strip-debug,
--trace,
--trace_symbol,
--traditional-format,
--unique,
--unresolved-symbols,
--verbose,
--warn-common,
--warn-constructors,
--warn-multiple-gp,
--warn-once,
--warn-section-align,
--warn-shared-textrel,
--warn-unresolved-symbols,
--wrap.
The following keywords are recognized by the
-z
option, but are currently unimplemented:
allextract,
defaultextract,
defs,
ignore,
initfirst,
lazyload,
muldefs,
nodefaultlib,
nodefs,
nodelete,
nodlopen,
nolazyload,
now,
origin,
record,
systemlibrary,
weakextract.
A
ld command first appeared in AT&T UNIX
Version 1.
The Elftoolchain implementation of
ld was written
by
Kai Wang
<
kaiwang27@gmail.com>.