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LD(1)			     GNU Development Tools			 LD(1)

NAME
       ld - The	GNU linker

SYNOPSIS
       ld [options] objfile ...

DESCRIPTION
       ld combines a number of object and archive files, relocates their data
       and ties	up symbol references. Usually the last step in compiling a
       program is to run ld.

       ld accepts Linker Command Language files	written	in a superset of
       AT&T's Link Editor Command Language syntax, to provide explicit and
       total control over the linking process.

       This man	page does not describe the command language; see the ld	entry
       in "info" for full details on the command language and on other aspects
       of the GNU linker.

       This version of ld uses the general purpose BFD libraries to operate on
       object files. This allows ld to read, combine, and write	object files
       in many different formats---for example,	COFF or	"a.out".  Different
       formats may be linked together to produce any available kind of object
       file.

       Aside from its flexibility, the GNU linker is more helpful than other
       linkers in providing diagnostic information.  Many linkers abandon
       execution immediately upon encountering an error; whenever possible, ld
       continues executing, allowing you to identify other errors (or, in some
       cases, to get an	output file in spite of	the error).

       The GNU linker ld is meant to cover a broad range of situations,	and to
       be as compatible	as possible with other linkers.	 As a result, you have
       many choices to control its behavior.

OPTIONS
       The linker supports a plethora of command-line options, but in actual
       practice	few of them are	used in	any particular context.	 For instance,
       a frequent use of ld is to link standard	Unix object files on a
       standard, supported Unix	system.	 On such a system, to link a file
       "hello.o":

	       ld -o <output> /lib/crt0.o hello.o -lc

       This tells ld to	produce	a file called output as	the result of linking
       the file	"/lib/crt0.o" with "hello.o" and the library "libc.a", which
       will come from the standard search directories.	(See the discussion of
       the -l option below.)

       Some of the command-line	options	to ld may be specified at any point in
       the command line.  However, options which refer to files, such as -l or
       -T, cause the file to be	read at	the point at which the option appears
       in the command line, relative to	the object files and other file
       options.	 Repeating non-file options with a different argument will
       either have no further effect, or override prior	occurrences (those
       further to the left on the command line)	of that	option.	 Options which
       may be meaningfully specified more than once are	noted in the
       descriptions below.

       Non-option arguments are	object files or	archives which are to be
       linked together.	 They may follow, precede, or be mixed in with
       command-line options, except that an object file	argument may not be
       placed between an option	and its	argument.

       Usually the linker is invoked with at least one object file, but	you
       can specify other forms of binary input files using -l, -R, and the
       script command language.	 If no binary input files at all are
       specified, the linker does not produce any output, and issues the
       message No input	files.

       If the linker cannot recognize the format of an object file, it will
       assume that it is a linker script.  A script specified in this way
       augments	the main linker	script used for	the link (either the default
       linker script or	the one	specified by using -T).	 This feature permits
       the linker to link against a file which appears to be an	object or an
       archive,	but actually merely defines some symbol	values,	or uses
       "INPUT" or "GROUP" to load other	objects.  Note that specifying a
       script in this way merely augments the main linker script; use the -T
       option to replace the default linker script entirely.

       For options whose names are a single letter, option arguments must
       either follow the option	letter without intervening whitespace, or be
       given as	separate arguments immediately following the option that
       requires	them.

       For options whose names are multiple letters, either one	dash or	two
       can precede the option name; for	example, -trace-symbol and
       --trace-symbol are equivalent.  Note---there is one exception to	this
       rule.  Multiple letter options that start with a	lower case 'o' can
       only be preceded	by two dashes.	This is	to reduce confusion with the
       -o option.  So for example -omagic sets the output file name to magic
       whereas --omagic	sets the NMAGIC	flag on	the output.

       Arguments to multiple-letter options must either	be separated from the
       option name by an equals	sign, or be given as separate arguments
       immediately following the option	that requires them.  For example,
       --trace-symbol foo and --trace-symbol=foo are equivalent.  Unique
       abbreviations of	the names of multiple-letter options are accepted.

       Note---if the linker is being invoked indirectly, via a compiler	driver
       (e.g. gcc) then all the linker command line options should be prefixed
       by -Wl, (or whatever is appropriate for the particular compiler driver)
       like this:

		 gcc -Wl,--startgroup foo.o bar.o -Wl,--endgroup

       This is important, because otherwise the	compiler driver	program	may
       silently	drop the linker	options, resulting in a	bad link.

       Here is a table of the generic command line switches accepted by	the
       GNU linker:

       @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.

       -akeyword
	   This	option is supported for	HP/UX compatibility.  The keyword
	   argument must be one	of the strings archive,	shared,	or default.
	   -aarchive is	functionally equivalent	to -Bstatic, and the other two
	   keywords are	functionally equivalent	to -Bdynamic.  This option may
	   be used any number of times.

       -Aarchitecture
       --architecture=architecture
	   In the current release of ld, this option is	useful only for	the
	   Intel 960 family of architectures.  In that ld configuration, the
	   architecture	argument identifies the	particular architecture	in the
	   960 family, enabling	some safeguards	and modifying the archive-
	   library search path.

	   Future releases of ld may support similar functionality for other
	   architecture	families.

       -b input-format
       --format=input-format
	   ld may be configured	to support more	than one kind of object	file.
	   If your ld is configured this way, you can use the -b option	to
	   specify the binary format for input object files that follow	this
	   option on the command line.	Even when ld is	configured to support
	   alternative object formats, you don't usually need to specify this,
	   as ld should	be configured to expect	as a default input format the
	   most	usual format on	each machine.  input-format is a text string,
	   the name of a particular format supported by	the BFD	libraries.
	   (You	can list the available binary formats with objdump -i.)

	   You may want	to use this option if you are linking files with an
	   unusual binary format.  You can also	use -b to switch formats
	   explicitly (when linking object files of different formats),	by
	   including -b	input-format before each group of object files in a
	   particular format.

	   The default format is taken from the	environment variable
	   "GNUTARGET".

	   You can also	define the input format	from a script, using the
	   command "TARGET";

       -c MRI-commandfile
       --mri-script=MRI-commandfile
	   For compatibility with linkers produced by MRI, ld accepts script
	   files written in an alternate, restricted command language,
	   described in	the MRI	Compatible Script Files	section	of GNU ld
	   documentation.  Introduce MRI script	files with the option -c; use
	   the -T option to run	linker scripts written in the general-purpose
	   ld scripting	language.  If MRI-cmdfile does not exist, ld looks for
	   it in the directories specified by any -L options.

       -d
       -dc
       -dp These three options are equivalent; multiple	forms are supported
	   for compatibility with other	linkers.  They assign space to common
	   symbols even	if a relocatable output	file is	specified (with	-r).
	   The script command "FORCE_COMMON_ALLOCATION"	has the	same effect.

       -e entry
       --entry=entry
	   Use entry as	the explicit symbol for	beginning execution of your
	   program, rather than	the default entry point.  If there is no
	   symbol named	entry, the linker will try to parse entry as a number,
	   and use that	as the entry address (the number will be interpreted
	   in base 10; you may use a leading 0x	for base 16, or	a leading 0
	   for base 8).

       --exclude-libs lib,lib,...
	   Specifies a list of archive libraries from which symbols should not
	   be automatically exported. The library names	may be delimited by
	   commas or colons.  Specifying "--exclude-libs ALL" excludes symbols
	   in all archive libraries from automatic export.  This option	is
	   available only for the i386 PE targeted port	of the linker and for
	   ELF targeted	ports.	For i386 PE, symbols explicitly	listed in a
	   .def	file are still exported, regardless of this option.  For ELF
	   targeted ports, symbols affected by this option will	be treated as
	   hidden.

       -E
       --export-dynamic
	   When	creating a dynamically linked executable, add all symbols to
	   the dynamic symbol table.  The dynamic symbol table is the set of
	   symbols which are visible from dynamic objects at run time.

	   If you do not use this option, the dynamic symbol table will
	   normally contain only those symbols which are referenced by some
	   dynamic object mentioned in the link.

	   If you use "dlopen" to load a dynamic object	which needs to refer
	   back	to the symbols defined by the program, rather than some	other
	   dynamic object, then	you will probably need to use this option when
	   linking the program itself.

	   You can also	use the	dynamic	list to	control	what symbols should be
	   added to the	dynamic	symbol table if	the output format supports it.
	   See the description of --dynamic-list.

       -EB Link	big-endian objects.  This affects the default output format.

       -EL Link	little-endian objects.	This affects the default output
	   format.

       -f
       --auxiliary name
	   When	creating an ELF	shared object, set the internal	DT_AUXILIARY
	   field to the	specified name.	 This tells the	dynamic	linker that
	   the symbol table of the shared object should	be used	as an
	   auxiliary filter on the symbol table	of the shared object name.

	   If you later	link a program against this filter object, then, when
	   you run the program,	the dynamic linker will	see the	DT_AUXILIARY
	   field.  If the dynamic linker resolves any symbols from the filter
	   object, it will first check whether there is	a definition in	the
	   shared object name.	If there is one, it will be used instead of
	   the definition in the filter	object.	 The shared object name	need
	   not exist.  Thus the	shared object name may be used to provide an
	   alternative implementation of certain functions, perhaps for
	   debugging or	for machine specific performance.

	   This	option may be specified	more than once.	 The DT_AUXILIARY
	   entries will	be created in the order	in which they appear on	the
	   command line.

       -F name
       --filter	name
	   When	creating an ELF	shared object, set the internal	DT_FILTER
	   field to the	specified name.	 This tells the	dynamic	linker that
	   the symbol table of the shared object which is being	created	should
	   be used as a	filter on the symbol table of the shared object	name.

	   If you later	link a program against this filter object, then, when
	   you run the program,	the dynamic linker will	see the	DT_FILTER
	   field.  The dynamic linker will resolve symbols according to	the
	   symbol table	of the filter object as	usual, but it will actually
	   link	to the definitions found in the	shared object name.  Thus the
	   filter object can be	used to	select a subset	of the symbols
	   provided by the object name.

	   Some	older linkers used the -F option throughout a compilation
	   toolchain for specifying object-file	format for both	input and
	   output object files.	 The GNU linker	uses other mechanisms for this
	   purpose: the	-b, --format, --oformat	options, the "TARGET" command
	   in linker scripts, and the "GNUTARGET" environment variable.	 The
	   GNU linker will ignore the -F option	when not creating an ELF
	   shared object.

       -fini name
	   When	creating an ELF	executable or shared object, call NAME when
	   the executable or shared object is unloaded,	by setting DT_FINI to
	   the address of the function.	 By default, the linker	uses "_fini"
	   as the function to call.

       -g  Ignored.  Provided for compatibility	with other tools.

       -Gvalue
       --gpsize=value
	   Set the maximum size	of objects to be optimized using the GP
	   register to size.  This is only meaningful for object file formats
	   such	as MIPS	ECOFF which supports putting large and small objects
	   into	different sections.  This is ignored for other object file
	   formats.

       -hname
       -soname=name
	   When	creating an ELF	shared object, set the internal	DT_SONAME
	   field to the	specified name.	 When an executable is linked with a
	   shared object which has a DT_SONAME field, then when	the executable
	   is run the dynamic linker will attempt to load the shared object
	   specified by	the DT_SONAME field rather than	the using the file
	   name	given to the linker.

       -i  Perform an incremental link (same as	option -r).

       -init name
	   When	creating an ELF	executable or shared object, call NAME when
	   the executable or shared object is loaded, by setting DT_INIT to
	   the address of the function.	 By default, the linker	uses "_init"
	   as the function to call.

       -lnamespec
       --library=namespec
	   Add the archive or object file specified by namespec	to the list of
	   files to link.  This	option may be used any number of times.	 If
	   namespec is of the form :filename, ld will search the library path
	   for a file called filename, otherise	it will	search the library
	   path	for a file called libnamespec.a.

	   On systems which support shared libraries, ld may also search for
	   files other than libnamespec.a.  Specifically, on ELF and SunOS
	   systems, ld will search a directory for a library called
	   libnamespec.so before searching for one called libnamespec.a.  (By
	   convention, a ".so" extension indicates a shared library.)  Note
	   that	this behavior does not apply to	:filename, which always
	   specifies a file called filename.

	   The linker will search an archive only once,	at the location	where
	   it is specified on the command line.	 If the	archive	defines	a
	   symbol which	was undefined in some object which appeared before the
	   archive on the command line,	the linker will	include	the
	   appropriate file(s) from the	archive.  However, an undefined	symbol
	   in an object	appearing later	on the command line will not cause the
	   linker to search the	archive	again.

	   See the -( option for a way to force	the linker to search archives
	   multiple times.

	   You may list	the same archive multiple times	on the command line.

	   This	type of	archive	searching is standard for Unix linkers.
	   However, if you are using ld	on AIX,	note that it is	different from
	   the behaviour of the	AIX linker.

       -Lsearchdir
       --library-path=searchdir
	   Add path searchdir to the list of paths that	ld will	search for
	   archive libraries and ld control scripts.  You may use this option
	   any number of times.	 The directories are searched in the order in
	   which they are specified on the command line.  Directories
	   specified on	the command line are searched before the default
	   directories.	 All -L	options	apply to all -l	options, regardless of
	   the order in	which the options appear.

	   If searchdir	begins with "=", then the "=" will be replaced by the
	   sysroot prefix, a path specified when the linker is configured.

	   The default set of paths searched (without being specified with -L)
	   depends on which emulation mode ld is using,	and in some cases also
	   on how it was configured.

	   The paths can also be specified in a	link script with the
	   "SEARCH_DIR"	command.  Directories specified	this way are searched
	   at the point	in which the linker script appears in the command
	   line.

       -memulation
	   Emulate the emulation linker.  You can list the available
	   emulations with the --verbose or -V options.

	   If the -m option is not used, the emulation is taken	from the
	   "LDEMULATION" environment variable, if that is defined.

	   Otherwise, the default emulation depends upon how the linker	was
	   configured.

       -M
       --print-map
	   Print a link	map to the standard output.  A link map	provides
	   information about the link, including the following:

	   o   Where object files are mapped into memory.

	   o   How common symbols are allocated.

	   o   All archive members included in the link, with a	mention	of the
	       symbol which caused the archive member to be brought in.

	   o   The values assigned to symbols.

	       Note - symbols whose values are computed	by an expression which
	       involves	a reference to a previous value	of the same symbol may
	       not have	correct	result displayed in the	link map.  This	is
	       because the linker discards intermediate	results	and only
	       retains the final value of an expression.  Under	such
	       circumstances the linker	will display the final value enclosed
	       by square brackets.  Thus for example a linker script
	       containing:

			  foo =	1
			  foo =	foo * 4
			  foo =	foo + 8

	       will produce the	following output in the	link map if the	-M
	       option is used:

			  0x00000001		    foo	= 0x1
			  [0x0000000c]		      foo = (foo * 0x4)
			  [0x0000000c]		      foo = (foo + 0x8)

	       See Expressions for more	information about expressions in
	       linker scripts.

       -n
       --nmagic
	   Turn	off page alignment of sections,	and mark the output as
	   "NMAGIC" if possible.

       -N
       --omagic
	   Set the text	and data sections to be	readable and writable.	Also,
	   do not page-align the data segment, and disable linking against
	   shared libraries.  If the output format supports Unix style magic
	   numbers, mark the output as "OMAGIC". Note: Although	a writable
	   text	section	is allowed for PE-COFF targets,	it does	not conform to
	   the format specification published by Microsoft.

       --no-omagic
	   This	option negates most of the effects of the -N option.  It sets
	   the text section to be read-only, and forces	the data segment to be
	   page-aligned.  Note - this option does not enable linking against
	   shared libraries.  Use -Bdynamic for	this.

       -o output
       --output=output
	   Use output as the name for the program produced by ld; if this
	   option is not specified, the	name a.out is used by default.	The
	   script command "OUTPUT" can also specify the	output file name.

       -O level
	   If level is a numeric values	greater	than zero ld optimizes the
	   output.  This might take significantly longer and therefore
	   probably should only	be enabled for the final binary.

       -q
       --emit-relocs
	   Leave relocation sections and contents in fully linked executables.
	   Post	link analysis and optimization tools may need this information
	   in order to perform correct modifications of	executables.  This
	   results in larger executables.

	   This	option is currently only supported on ELF platforms.

       --force-dynamic
	   Force the output file to have dynamic sections.  This option	is
	   specific to VxWorks targets.

       -r
       --relocatable
	   Generate relocatable	output---i.e., generate	an output file that
	   can in turn serve as	input to ld.  This is often called partial
	   linking.  As	a side effect, in environments that support standard
	   Unix	magic numbers, this option also	sets the output	file's magic
	   number to "OMAGIC".	If this	option is not specified, an absolute
	   file	is produced.  When linking C++ programs, this option will not
	   resolve references to constructors; to do that, use -Ur.

	   When	an input file does not have the	same format as the output
	   file, partial linking is only supported if that input file does not
	   contain any relocations.  Different output formats can have further
	   restrictions; for example some "a.out"-based	formats	do not support
	   partial linking with	input files in other formats at	all.

	   This	option does the	same thing as -i.

       -R filename
       --just-symbols=filename
	   Read	symbol names and their addresses from filename,	but do not
	   relocate it or include it in	the output.  This allows your output
	   file	to refer symbolically to absolute locations of memory defined
	   in other programs.  You may use this	option more than once.

	   For compatibility with other	ELF linkers, if	the -R option is
	   followed by a directory name, rather	than a file name, it is
	   treated as the -rpath option.

       -s
       --strip-all
	   Omit	all symbol information from the	output file.

       -S
       --strip-debug
	   Omit	debugger symbol	information (but not all symbols) from the
	   output file.

       -t
       --trace
	   Print the names of the input	files as ld processes them.

       -T scriptfile
       --script=scriptfile
	   Use scriptfile as the linker	script.	 This script replaces ld's
	   default linker script (rather than adding to	it), so	commandfile
	   must	specify	everything necessary to	describe the output file.
	   If scriptfile does not exist	in the current directory, "ld" looks
	   for it in the directories specified by any preceding	-L options.
	   Multiple -T options accumulate.

       -dT scriptfile
       --default-script=scriptfile
	   Use scriptfile as the default linker	script.

	   This	option is similar to the --script option except	that
	   processing of the script is delayed until after the rest of the
	   command line	has been processed.  This allows options placed	after
	   the --default-script	option on the command line to affect the
	   behaviour of	the linker script, which can be	important when the
	   linker command line cannot be directly controlled by	the user.  (eg
	   because the command line is being constructed by another tool, such
	   as gcc).

       -u symbol
       --undefined=symbol
	   Force symbol	to be entered in the output file as an undefined
	   symbol.  Doing this may, for	example, trigger linking of additional
	   modules from	standard libraries.  -u	may be repeated	with different
	   option arguments to enter additional	undefined symbols.  This
	   option is equivalent	to the "EXTERN"	linker script command.

       -Ur For anything	other than C++ programs, this option is	equivalent to
	   -r: it generates relocatable	output---i.e., an output file that can
	   in turn serve as input to ld.  When linking C++ programs, -Ur does
	   resolve references to constructors, unlike -r.  It does not work to
	   use -Ur on files that were themselves linked	with -Ur; once the
	   constructor table has been built, it	cannot be added	to.  Use -Ur
	   only	for the	last partial link, and -r for the others.

       --unique[=SECTION]
	   Creates a separate output section for every input section matching
	   SECTION, or if the optional wildcard	SECTION	argument is missing,
	   for every orphan input section.  An orphan section is one not
	   specifically	mentioned in a linker script.  You may use this	option
	   multiple times on the command line;	It prevents the	normal merging
	   of input sections with the same name, overriding output section
	   assignments in a linker script.

       -v
       --version
       -V  Display the version number for ld.  The -V option also lists	the
	   supported emulations.

       -x
       --discard-all
	   Delete all local symbols.

       -X
       --discard-locals
	   Delete all temporary	local symbols.	(These symbols start with
	   system-specific local label prefixes, typically .L for ELF systems
	   or L	for traditional	a.out systems.)

       -y symbol
       --trace-symbol=symbol
	   Print the name of each linked file in which symbol appears.	This
	   option may be given any number of times.  On	many systems it	is
	   necessary to	prepend	an underscore.

	   This	option is useful when you have an undefined symbol in your
	   link	but don't know where the reference is coming from.

       -Y path
	   Add path to the default library search path.	 This option exists
	   for Solaris compatibility.

       -z keyword
	   The recognized keywords are:

	   combreloc
	       Combines	multiple reloc sections	and sorts them to make dynamic
	       symbol lookup caching possible.

	   defs
	       Disallows undefined symbols in object files.  Undefined symbols
	       in shared libraries are still allowed.

	   execstack
	       Marks the object	as requiring executable	stack.

	   initfirst
	       This option is only meaningful when building a shared object.
	       It marks	the object so that its runtime initialization will
	       occur before the	runtime	initialization of any other objects
	       brought into the	process	at the same time.  Similarly the
	       runtime finalization of the object will occur after the runtime
	       finalization of any other objects.

	   interpose
	       Marks the object	that its symbol	table interposes before	all
	       symbols but the primary executable.

	   lazy
	       When generating an executable or	shared library,	mark it	to
	       tell the	dynamic	linker to defer	function call resolution to
	       the point when the function is called (lazy binding), rather
	       than at load time.  Lazy	binding	is the default.

	   loadfltr
	       Marks  the object that its filters be processed immediately at
	       runtime.

	   muldefs
	       Allows multiple definitions.

	   nocombreloc
	       Disables	multiple reloc sections	combining.

	   nocopyreloc
	       Disables	production of copy relocs.

	   nodefaultlib
	       Marks the object	that the search	for dependencies of this
	       object will ignore any default library search paths.

	   nodelete
	       Marks the object	shouldn't be unloaded at runtime.

	   nodlopen
	       Marks the object	not available to "dlopen".

	   nodump
	       Marks the object	can not	be dumped by "dldump".

	   noexecstack
	       Marks the object	as not requiring executable stack.

	   norelro
	       Don't create an ELF "PT_GNU_RELRO" segment header in the
	       object.

	   now When generating an executable or	shared library,	mark it	to
	       tell the	dynamic	linker to resolve all symbols when the program
	       is started, or when the shared library is linked	to using
	       dlopen, instead of deferring function call resolution to	the
	       point when the function is first	called.

	   origin
	       Marks the object	may contain $ORIGIN.

	   relro
	       Create an ELF "PT_GNU_RELRO" segment header in the object.

	   max-page-size=value
	       Set the emulation maximum page size to value.

	   common-page-size=value
	       Set the emulation common	page size to value.

	   Other keywords are ignored for Solaris compatibility.

       -( archives -)
       --start-group archives --end-group
	   The archives	should be a list of archive files.  They may be	either
	   explicit file names,	or -l options.

	   The specified archives are searched repeatedly until	no new
	   undefined references	are created.  Normally,	an archive is searched
	   only	once in	the order that it is specified on the command line.
	   If a	symbol in that archive is needed to resolve an undefined
	   symbol referred to by an object in an archive that appears later on
	   the command line, the linker	would not be able to resolve that
	   reference.  By grouping the archives, they all be searched
	   repeatedly until all	possible references are	resolved.

	   Using this option has a significant performance cost.  It is	best
	   to use it only when there are unavoidable circular references
	   between two or more archives.

       --accept-unknown-input-arch
       --no-accept-unknown-input-arch
	   Tells the linker to accept input files whose	architecture cannot be
	   recognised.	The assumption is that the user	knows what they	are
	   doing and deliberately wants	to link	in these unknown input files.
	   This	was the	default	behaviour of the linker, before	release	2.14.
	   The default behaviour from release 2.14 onwards is to reject	such
	   input files,	and so the --accept-unknown-input-arch option has been
	   added to restore the	old behaviour.

       --as-needed
       --no-as-needed
	   This	option affects ELF DT_NEEDED tags for dynamic libraries
	   mentioned on	the command line after the --as-needed option.
	   Normally, the linker	will add a DT_NEEDED tag for each dynamic
	   library mentioned on	the command line, regardless of	whether	the
	   library is actually needed.	--as-needed causes DT_NEEDED tags to
	   only	be emitted for libraries that satisfy some symbol reference
	   from	regular	objects	which is undefined at the point	that the
	   library was linked.	--no-as-needed restores	the default behaviour.

       --add-needed
       --no-add-needed
	   This	option affects the treatment of	dynamic	libraries from ELF
	   DT_NEEDED tags in dynamic libraries mentioned on the	command	line
	   after the --no-add-needed option.  Normally,	the linker will	add a
	   DT_NEEDED tag for each dynamic library from DT_NEEDED tags.
	   --no-add-needed causes DT_NEEDED tags will never be emitted for
	   those libraries from	DT_NEEDED tags.	--add-needed restores the
	   default behaviour.

       -assert keyword
	   This	option is ignored for SunOS compatibility.

       -Bdynamic
       -dy
       -call_shared
	   Link	against	dynamic	libraries.  This is only meaningful on
	   platforms for which shared libraries	are supported.	This option is
	   normally the	default	on such	platforms.  The	different variants of
	   this	option are for compatibility with various systems.  You	may
	   use this option multiple times on the command line: it affects
	   library searching for -l options which follow it.

       -Bgroup
	   Set the "DF_1_GROUP"	flag in	the "DT_FLAGS_1" entry in the dynamic
	   section.  This causes the runtime linker to handle lookups in this
	   object and its dependencies to be performed only inside the group.
	   --unresolved-symbols=report-all is implied.	This option is only
	   meaningful on ELF platforms which support shared libraries.

       -Bstatic
       -dn
       -non_shared
       -static
	   Do not link against shared libraries.  This is only meaningful on
	   platforms for which shared libraries	are supported.	The different
	   variants of this option are for compatibility with various systems.
	   You may use this option multiple times on the command line: it
	   affects library searching for -l options which follow it.  This
	   option also implies --unresolved-symbols=report-all.	 This option
	   can be used with -shared.  Doing so means that a shared library is
	   being created but that all of the library's external	references
	   must	be resolved by pulling in entries from static libraries.

       -Bsymbolic
	   When	creating a shared library, bind	references to global symbols
	   to the definition within the	shared library,	if any.	 Normally, it
	   is possible for a program linked against a shared library to
	   override the	definition within the shared library.  This option is
	   only	meaningful on ELF platforms which support shared libraries.

       -Bsymbolic-functions
	   When	creating a shared library, bind	references to global function
	   symbols to the definition within the	shared library,	if any.	 This
	   option is only meaningful on	ELF platforms which support shared
	   libraries.

       --dynamic-list=dynamic-list-file
	   Specify the name of a dynamic list file to the linker.  This	is
	   typically used when creating	shared libraries to specify a list of
	   global symbols whose	references shouldn't be	bound to the
	   definition within the shared	library, or creating dynamically
	   linked executables to specify a list	of symbols which should	be
	   added to the	symbol table in	the executable.	 This option is	only
	   meaningful on ELF platforms which support shared libraries.

	   The format of the dynamic list is the same as the version node
	   without scope and node name.	 See VERSION for more information.

       --dynamic-list-data
	   Include all global data symbols to the dynamic list.

       --dynamic-list-cpp-new
	   Provide the builtin dynamic list for	C++ operator new and delete.
	   It is mainly	useful for building shared libstdc++.

       --dynamic-list-cpp-typeinfo
	   Provide the builtin dynamic list for	C++ runtime type
	   identification.

       --check-sections
       --no-check-sections
	   Asks	the linker not to check	section	addresses after	they have been
	   assigned to see if there are	any overlaps.  Normally	the linker
	   will	perform	this check, and	if it finds any	overlaps it will
	   produce suitable error messages.  The linker	does know about, and
	   does	make allowances	for sections in	overlays.  The default
	   behaviour can be restored by	using the command line switch
	   --check-sections.

       --cref
	   Output a cross reference table.  If a linker	map file is being
	   generated, the cross	reference table	is printed to the map file.
	   Otherwise, it is printed on the standard output.

	   The format of the table is intentionally simple, so that it may be
	   easily processed by a script	if necessary.  The symbols are printed
	   out,	sorted by name.	 For each symbol, a list of file names is
	   given.  If the symbol is defined, the first file listed is the
	   location of the definition.	The remaining files contain references
	   to the symbol.

       --no-define-common
	   This	option inhibits	the assignment of addresses to common symbols.
	   The script command "INHIBIT_COMMON_ALLOCATION" has the same effect.

	   The --no-define-common option allows	decoupling the decision	to
	   assign addresses to Common symbols from the choice of the output
	   file	type; otherwise	a non-Relocatable output type forces assigning
	   addresses to	Common symbols.	 Using --no-define-common allows
	   Common symbols that are referenced from a shared library to be
	   assigned addresses only in the main program.	 This eliminates the
	   unused duplicate space in the shared	library, and also prevents any
	   possible confusion over resolving to	the wrong duplicate when there
	   are many dynamic modules with specialized search paths for runtime
	   symbol resolution.

       --defsym	symbol=expression
	   Create a global symbol in the output	file, containing the absolute
	   address given by expression.	 You may use this option as many times
	   as necessary	to define multiple symbols in the command line.	 A
	   limited form	of arithmetic is supported for the expression in this
	   context: you	may give a hexadecimal constant	or the name of an
	   existing symbol, or use "+" and "-" to add or subtract hexadecimal
	   constants or	symbols.  If you need more elaborate expressions,
	   consider using the linker command language from a script.  Note:
	   there should	be no white space between symbol, the equals sign
	   ("="), and expression.

       --demangle[=style]
       --no-demangle
	   These options control whether to demangle symbol names in error
	   messages and	other output.  When the	linker is told to demangle, it
	   tries to present symbol names in a readable fashion:	it strips
	   leading underscores if they are used	by the object file format, and
	   converts C++	mangled	symbol names into user readable	names.
	   Different compilers have different mangling styles.	The optional
	   demangling style argument can be used to choose an appropriate
	   demangling style for	your compiler.	The linker will	demangle by
	   default unless the environment variable COLLECT_NO_DEMANGLE is set.
	   These options may be	used to	override the default.

       --dynamic-linker	file
	   Set the name	of the dynamic linker.	This is	only meaningful	when
	   generating dynamically linked ELF executables.  The default dynamic
	   linker is normally correct; don't use this unless you know what you
	   are doing.

       --fatal-warnings
	   Treat all warnings as errors.

       --force-exe-suffix
	   Make	sure that an output file has a .exe suffix.

	   If a	successfully built fully linked	output file does not have a
	   ".exe" or ".dll" suffix, this option	forces the linker to copy the
	   output file to one of the same name with a ".exe" suffix. This
	   option is useful when using unmodified Unix makefiles on a
	   Microsoft Windows host, since some versions of Windows won't	run an
	   image unless	it ends	in a ".exe" suffix.

       --gc-sections
       --no-gc-sections
	   Enable garbage collection of	unused input sections.	It is ignored
	   on targets that do not support this option.	This option is not
	   compatible with -r or --emit-relocs.	The default behaviour (of not
	   performing this garbage collection) can be restored by specifying
	   --no-gc-sections on the command line.

       --print-gc-sections
       --no-print-gc-sections
	   List	all sections removed by	garbage	collection.  The listing is
	   printed on stderr.  This option is only effective if	garbage
	   collection has been enabled via the --gc-sections) option.  The
	   default behaviour (of not listing the sections that are removed)
	   can be restored by specifying --no-print-gc-sections	on the command
	   line.

       --help
	   Print a summary of the command-line options on the standard output
	   and exit.

       --target-help
	   Print a summary of all target specific options on the standard
	   output and exit.

       -Map mapfile
	   Print a link	map to the file	mapfile.  See the description of the
	   -M option, above.

       --no-keep-memory
	   ld normally optimizes for speed over	memory usage by	caching	the
	   symbol tables of input files	in memory.  This option	tells ld to
	   instead optimize for	memory usage, by rereading the symbol tables
	   as necessary.  This may be required if ld runs out of memory	space
	   while linking a large executable.

       --no-undefined
       -z defs
	   Report unresolved symbol references from regular object files.
	   This	is done	even if	the linker is creating a non-symbolic shared
	   library.  The switch	--[no-]allow-shlib-undefined controls the
	   behaviour for reporting unresolved references found in shared
	   libraries being linked in.

       --allow-multiple-definition
       -z muldefs
	   Normally when a symbol is defined multiple times, the linker	will
	   report a fatal error. These options allow multiple definitions and
	   the first definition	will be	used.

       --allow-shlib-undefined
       --no-allow-shlib-undefined
	   Allows (the default)	or disallows undefined symbols in shared
	   libraries.  This switch is similar to --no-undefined	except that it
	   determines the behaviour when the undefined symbols are in a	shared
	   library rather than a regular object	file.  It does not affect how
	   undefined symbols in	regular	object files are handled.

	   The reason that --allow-shlib-undefined is the default is that the
	   shared library being	specified at link time may not be the same as
	   the one that	is available at	load time, so the symbols might
	   actually be resolvable at load time.	 Plus there are	some systems,
	   (eg BeOS) where undefined symbols in	shared libraries is normal.
	   (The	kernel patches them at load time to select which function is
	   most	appropriate for	the current architecture.  This	is used	for
	   example to dynamically select an appropriate	memset function).
	   Apparently it is also normal	for HPPA shared	libraries to have
	   undefined symbols.

       --no-undefined-version
	   Normally when a symbol has an undefined version, the	linker will
	   ignore it. This option disallows symbols with undefined version and
	   a fatal error will be issued	instead.

       --default-symver
	   Create and use a default symbol version (the	soname)	for
	   unversioned exported	symbols.

       --default-imported-symver
	   Create and use a default symbol version (the	soname)	for
	   unversioned imported	symbols.

       --no-warn-mismatch
	   Normally ld will give an error if you try to	link together input
	   files that are mismatched for some reason, perhaps because they
	   have	been compiled for different processors or for different
	   endiannesses.  This option tells ld that it should silently permit
	   such	possible errors.  This option should only be used with care,
	   in cases when you have taken	some special action that ensures that
	   the linker errors are inappropriate.

       --no-warn-search-mismatch
	   Normally ld will give a warning if it finds an incompatible library
	   during a library search.  This option silences the warning.

       --no-whole-archive
	   Turn	off the	effect of the --whole-archive option for subsequent
	   archive files.

       --noinhibit-exec
	   Retain the executable output	file whenever it is still usable.
	   Normally, the linker	will not produce an output file	if it
	   encounters errors during the	link process; it exits without writing
	   an output file when it issues any error whatsoever.

       -nostdlib
	   Only	search library directories explicitly specified	on the command
	   line.  Library directories specified	in linker scripts (including
	   linker scripts specified on the command line) are ignored.

       --oformat output-format
	   ld may be configured	to support more	than one kind of object	file.
	   If your ld is configured this way, you can use the --oformat	option
	   to specify the binary format	for the	output object file.  Even when
	   ld is configured to support alternative object formats, you don't
	   usually need	to specify this, as ld should be configured to produce
	   as a	default	output format the most usual format on each machine.
	   output-format is a text string, the name of a particular format
	   supported by	the BFD	libraries.  (You can list the available	binary
	   formats with	objdump	-i.)  The script command "OUTPUT_FORMAT" can
	   also	specify	the output format, but this option overrides it.

       -pie
       --pic-executable
	   Create a position independent executable.  This is currently	only
	   supported on	ELF platforms.	Position independent executables are
	   similar to shared libraries in that they are	relocated by the
	   dynamic linker to the virtual address the OS	chooses	for them
	   (which can vary between invocations).  Like normal dynamically
	   linked executables they can be executed and symbols defined in the
	   executable cannot be	overridden by shared libraries.

       -qmagic
	   This	option is ignored for Linux compatibility.

       -Qy This	option is ignored for SVR4 compatibility.

       --relax
	   An option with machine dependent effects.  This option is only
	   supported on	a few targets.

	   On some platforms, the --relax option performs global optimizations
	   that	become possible	when the linker	resolves addressing in the
	   program, such as relaxing address modes and synthesizing new
	   instructions	in the output object file.

	   On some platforms these link	time global optimizations may make
	   symbolic debugging of the resulting executable impossible.  This is
	   known to be the case	for the	Matsushita MN10200 and MN10300 family
	   of processors.

	   On platforms	where this is not supported, --relax is	accepted, but
	   ignored.

       --retain-symbols-file filename
	   Retain only the symbols listed in the file filename,	discarding all
	   others.  filename is	simply a flat file, with one symbol name per
	   line.  This option is especially useful in environments (such as
	   VxWorks) where a large global symbol	table is accumulated
	   gradually, to conserve run-time memory.

	   --retain-symbols-file does not discard undefined symbols, or
	   symbols needed for relocations.

	   You may only	specify	--retain-symbols-file once in the command
	   line.  It overrides -s and -S.

       -rpath dir
	   Add a directory to the runtime library search path.	This is	used
	   when	linking	an ELF executable with shared objects.	All -rpath
	   arguments are concatenated and passed to the	runtime	linker,	which
	   uses	them to	locate shared objects at runtime.  The -rpath option
	   is also used	when locating shared objects which are needed by
	   shared objects explicitly included in the link; see the description
	   of the -rpath-link option.  If -rpath is not	used when linking an
	   ELF executable, the contents	of the environment variable
	   "LD_RUN_PATH" will be used if it is defined.

	   The -rpath option may also be used on SunOS.	 By default, on	SunOS,
	   the linker will form	a runtime search patch out of all the -L
	   options it is given.	 If a -rpath option is used, the runtime
	   search path will be formed exclusively using	the -rpath options,
	   ignoring the	-L options.  This can be useful	when using gcc,	which
	   adds	many -L	options	which may be on	NFS mounted file systems.

	   For compatibility with other	ELF linkers, if	the -R option is
	   followed by a directory name, rather	than a file name, it is
	   treated as the -rpath option.

       -rpath-link DIR
	   When	using ELF or SunOS, one	shared library may require another.
	   This	happens	when an	"ld -shared" link includes a shared library as
	   one of the input files.

	   When	the linker encounters such a dependency	when doing a non-
	   shared, non-relocatable link, it will automatically try to locate
	   the required	shared library and include it in the link, if it is
	   not included	explicitly.  In	such a case, the -rpath-link option
	   specifies the first set of directories to search.  The -rpath-link
	   option may specify a	sequence of directory names either by
	   specifying a	list of	names separated	by colons, or by appearing
	   multiple times.

	   This	option should be used with caution as it overrides the search
	   path	that may have been hard	compiled into a	shared library.	In
	   such	a case it is possible to use unintentionally a different
	   search path than the	runtime	linker would do.

	   The linker uses the following search	paths to locate	required
	   shared libraries:

	   1.  Any directories specified by -rpath-link	options.

	   2.  Any directories specified by -rpath options.  The difference
	       between -rpath and -rpath-link is that directories specified by
	       -rpath options are included in the executable and used at
	       runtime,	whereas	the -rpath-link	option is only effective at
	       link time. Searching -rpath in this way is only supported by
	       native linkers and cross	linkers	which have been	configured
	       with the	--with-sysroot option.

	   3.  On an ELF system, if the	-rpath and "rpath-link"	options	were
	       not used, search	the contents of	the environment	variable
	       "LD_RUN_PATH". It is for	the native linker only.

	   4.  On SunOS, if the	-rpath option was not used, search any
	       directories specified using -L options.

	   5.  For a native linker, the	contents of the	environment variable
	       "LD_LIBRARY_PATH".

	   6.  For a native ELF	linker,	the directories	in "DT_RUNPATH"	or
	       "DT_RPATH" of a shared library are searched for shared
	       libraries needed	by it. The "DT_RPATH" entries are ignored if
	       "DT_RUNPATH" entries exist.

	   7.  The default directories,	normally /lib and /usr/lib.

	   8.  For a native linker on an ELF system, if	the file
	       /etc/ld.so.conf exists, the list	of directories found in	that
	       file.

	   If the required shared library is not found,	the linker will	issue
	   a warning and continue with the link.

       -shared
       -Bshareable
	   Create a shared library.  This is currently only supported on ELF,
	   XCOFF and SunOS platforms.  On SunOS, the linker will automatically
	   create a shared library if the -e option is not used	and there are
	   undefined symbols in	the link.

       --sort-common
	   This	option tells ld	to sort	the common symbols by size when	it
	   places them in the appropriate output sections.  First come all the
	   one byte symbols, then all the two byte, then all the four byte,
	   and then everything else.  This is to prevent gaps between symbols
	   due to alignment constraints.

       --sort-section name
	   This	option will apply "SORT_BY_NAME" to all	wildcard section
	   patterns in the linker script.

       --sort-section alignment
	   This	option will apply "SORT_BY_ALIGNMENT" to all wildcard section
	   patterns in the linker script.

       --split-by-file [size]
	   Similar to --split-by-reloc but creates a new output	section	for
	   each	input file when	size is	reached.  size defaults	to a size of 1
	   if not given.

       --split-by-reloc	[count]
	   Tries to creates extra sections in the output file so that no
	   single output section in the	file contains more than	count
	   relocations.	 This is useful	when generating	huge relocatable files
	   for downloading into	certain	real time kernels with the COFF	object
	   file	format;	since COFF cannot represent more than 65535
	   relocations in a single section.  Note that this will fail to work
	   with	object file formats which do not support arbitrary sections.
	   The linker will not split up	individual input sections for
	   redistribution, so if a single input	section	contains more than
	   count relocations one output	section	will contain that many
	   relocations.	 count defaults	to a value of 32768.

       --stats
	   Compute and display statistics about	the operation of the linker,
	   such	as execution time and memory usage.

       --sysroot=directory
	   Use directory as the	location of the	sysroot, overriding the
	   configure-time default.  This option	is only	supported by linkers
	   that	were configured	using --with-sysroot.

       --traditional-format
	   For some targets, the output	of ld is different in some ways	from
	   the output of some existing linker.	This switch requests ld	to use
	   the traditional format instead.

	   For example,	on SunOS, ld combines duplicate	entries	in the symbol
	   string table.  This can reduce the size of an output	file with full
	   debugging information by over 30 percent.  Unfortunately, the SunOS
	   "dbx" program can not read the resulting program ("gdb" has no
	   trouble).  The --traditional-format switch tells ld to not combine
	   duplicate entries.

       --section-start sectionname=org
	   Locate a section in the output file at the absolute address given
	   by org.  You	may use	this option as many times as necessary to
	   locate multiple sections in the command line.  org must be a	single
	   hexadecimal integer;	for compatibility with other linkers, you may
	   omit	the leading 0x usually associated with hexadecimal values.
	   Note: there should be no white space	between	sectionname, the
	   equals sign ("="), and org.

       -Tbss org
       -Tdata org
       -Ttext org
	   Same	as --section-start, with ".bss", ".data" or ".text" as the
	   sectionname.

       --unresolved-symbols=method
	   Determine how to handle unresolved symbols.	There are four
	   possible values for method:

	   ignore-all
	       Do not report any unresolved symbols.

	   report-all
	       Report all unresolved symbols.  This is the default.

	   ignore-in-object-files
	       Report unresolved symbols that are contained in shared
	       libraries, but ignore them if they come from regular object
	       files.

	   ignore-in-shared-libs
	       Report unresolved symbols that come from	regular	object files,
	       but ignore them if they come from shared	libraries.  This can
	       be useful when creating a dynamic binary	and it is known	that
	       all the shared libraries	that it	should be referencing are
	       included	on the linker's	command	line.

	   The behaviour for shared libraries on their own can also be
	   controlled by the --[no-]allow-shlib-undefined option.

	   Normally the	linker will generate an	error message for each
	   reported unresolved symbol but the option --warn-unresolved-symbols
	   can change this to a	warning.

       --dll-verbose
       --verbose
	   Display the version number for ld and list the linker emulations
	   supported.  Display which input files can and cannot	be opened.
	   Display the linker script being used	by the linker.

       --version-script=version-scriptfile
	   Specify the name of a version script	to the linker.	This is
	   typically used when creating	shared libraries to specify additional
	   information about the version hierarchy for the library being
	   created.  This option is only meaningful on ELF platforms which
	   support shared libraries.

       --warn-common
	   Warn	when a common symbol is	combined with another common symbol or
	   with	a symbol definition.  Unix linkers allow this somewhat sloppy
	   practise, but linkers on some other operating systems do not.  This
	   option allows you to	find potential problems	from combining global
	   symbols.  Unfortunately, some C libraries use this practise,	so you
	   may get some	warnings about symbols in the libraries	as well	as in
	   your	programs.

	   There are three kinds of global symbols, illustrated	here by	C
	   examples:

	   int i = 1;
	       A definition, which goes	in the initialized data	section	of the
	       output file.

	   extern int i;
	       An undefined reference, which does not allocate space.  There
	       must be either a	definition or a	common symbol for the variable
	       somewhere.

	   int i;
	       A common	symbol.	 If there are only (one	or more) common
	       symbols for a variable, it goes in the uninitialized data area
	       of the output file.  The	linker merges multiple common symbols
	       for the same variable into a single symbol.  If they are	of
	       different sizes,	it picks the largest size.  The	linker turns a
	       common symbol into a declaration, if there is a definition of
	       the same	variable.

	   The --warn-common option can	produce	five kinds of warnings.	 Each
	   warning consists of a pair of lines:	the first describes the	symbol
	   just	encountered, and the second describes the previous symbol
	   encountered with the	same name.  One	or both	of the two symbols
	   will	be a common symbol.

	   1.  Turning a common	symbol into a reference, because there is
	       already a definition for	the symbol.

		       <file>(<section>): warning: common of `<symbol>'
			  overridden by	definition
		       <file>(<section>): warning: defined here

	   2.  Turning a common	symbol into a reference, because a later
	       definition for the symbol is encountered.  This is the same as
	       the previous case, except that the symbols are encountered in a
	       different order.

		       <file>(<section>): warning: definition of `<symbol>'
			  overriding common
		       <file>(<section>): warning: common is here

	   3.  Merging a common	symbol with a previous same-sized common
	       symbol.

		       <file>(<section>): warning: multiple common
			  of `<symbol>'
		       <file>(<section>): warning: previous common is here

	   4.  Merging a common	symbol with a previous larger common symbol.

		       <file>(<section>): warning: common of `<symbol>'
			  overridden by	larger common
		       <file>(<section>): warning: larger common is here

	   5.  Merging a common	symbol with a previous smaller common symbol.
	       This is the same	as the previous	case, except that the symbols
	       are encountered in a different order.

		       <file>(<section>): warning: common of `<symbol>'
			  overriding smaller common
		       <file>(<section>): warning: smaller common is here

       --warn-constructors
	   Warn	if any global constructors are used.  This is only useful for
	   a few object	file formats.  For formats like	COFF or	ELF, the
	   linker can not detect the use of global constructors.

       --warn-multiple-gp
	   Warn	if multiple global pointer values are required in the output
	   file.  This is only meaningful for certain processors, such as the
	   Alpha.  Specifically, some processors put large-valued constants in
	   a special section.  A special register (the global pointer) points
	   into	the middle of this section, so that constants can be loaded
	   efficiently via a base-register relative addressing mode.  Since
	   the offset in base-register relative	mode is	fixed and relatively
	   small (e.g.,	16 bits), this limits the maximum size of the constant
	   pool.  Thus,	in large programs, it is often necessary to use
	   multiple global pointer values in order to be able to address all
	   possible constants.	This option causes a warning to	be issued
	   whenever this case occurs.

       --warn-once
	   Only	warn once for each undefined symbol, rather than once per
	   module which	refers to it.

       --warn-section-align
	   Warn	if the address of an output section is changed because of
	   alignment.  Typically, the alignment	will be	set by an input
	   section.  The address will only be changed if it not	explicitly
	   specified; that is, if the "SECTIONS" command does not specify a
	   start address for the section.

       --warn-shared-textrel
	   Warn	if the linker adds a DT_TEXTREL	to a shared object.

       --warn-unresolved-symbols
	   If the linker is going to report an unresolved symbol (see the
	   option --unresolved-symbols)	it will	normally generate an error.
	   This	option makes it	generate a warning instead.

       --error-unresolved-symbols
	   This	restores the linker's default behaviour	of generating errors
	   when	it is reporting	unresolved symbols.

       --whole-archive
	   For each archive mentioned on the command line after	the
	   --whole-archive option, include every object	file in	the archive in
	   the link, rather than searching the archive for the required	object
	   files.  This	is normally used to turn an archive file into a	shared
	   library, forcing every object to be included	in the resulting
	   shared library.  This option	may be used more than once.

	   Two notes when using	this option from gcc: First, gcc doesn't know
	   about this option, so you have to use -Wl,-whole-archive.  Second,
	   don't forget	to use -Wl,-no-whole-archive after your	list of
	   archives, because gcc will add its own list of archives to your
	   link	and you	may not	want this flag to affect those as well.

       --wrap symbol
	   Use a wrapper function for symbol.  Any undefined reference to
	   symbol will be resolved to "__wrap_symbol".	Any undefined
	   reference to	"__real_symbol"	will be	resolved to symbol.

	   This	can be used to provide a wrapper for a system function.	 The
	   wrapper function should be called "__wrap_symbol".  If it wishes to
	   call	the system function, it	should call "__real_symbol".

	   Here	is a trivial example:

		   void	*
		   __wrap_malloc (size_t c)
		   {
		     printf ("malloc called with %zu\n", c);
		     return __real_malloc (c);
		   }

	   If you link other code with this file using --wrap malloc, then all
	   calls to "malloc" will call the function "__wrap_malloc" instead.
	   The call to "__real_malloc" in "__wrap_malloc" will call the	real
	   "malloc" function.

	   You may wish	to provide a "__real_malloc" function as well, so that
	   links without the --wrap option will	succeed.  If you do this, you
	   should not put the definition of "__real_malloc" in the same	file
	   as "__wrap_malloc"; if you do, the assembler	may resolve the	call
	   before the linker has a chance to wrap it to	"malloc".

       --eh-frame-hdr
	   Request creation of ".eh_frame_hdr" section and ELF
	   "PT_GNU_EH_FRAME" segment header.

       --enable-new-dtags
       --disable-new-dtags
	   This	linker can create the new dynamic tags in ELF. But the older
	   ELF systems may not understand them.	If you specify
	   --enable-new-dtags, the dynamic tags	will be	created	as needed.  If
	   you specify --disable-new-dtags, no new dynamic tags	will be
	   created. By default,	the new	dynamic	tags are not created. Note
	   that	those options are only available for ELF systems.

       --hash-size=number
	   Set the default size	of the linker's	hash tables to a prime number
	   close to number.  Increasing	this value can reduce the length of
	   time	it takes the linker to perform its tasks, at the expense of
	   increasing the linker's memory requirements.	 Similarly reducing
	   this	value can reduce the memory requirements at the	expense	of
	   speed.

       --hash-style=style
	   Set the type	of linker's hash table(s).  style can be either	"sysv"
	   for classic ELF ".hash" section, "gnu" for new style	GNU
	   ".gnu.hash" section or "both" for both the classic ELF ".hash" and
	   new style GNU ".gnu.hash" hash tables.  The default is "sysv".

       --reduce-memory-overheads
	   This	option reduces memory requirements at ld runtime, at the
	   expense of linking speed.  This was introduced to select the	old
	   O(n^2) algorithm for	link map file generation, rather than the new
	   O(n)	algorithm which	uses about 40% more memory for symbol storage.

	   Another effect of the switch	is to set the default hash table size
	   to 1021, which again	saves memory at	the cost of lengthening	the
	   linker's run	time.  This is not done	however	if the --hash-size
	   switch has been used.

	   The --reduce-memory-overheads switch	may be also be used to enable
	   other tradeoffs in future versions of the linker.

       The i386	PE linker supports the -shared option, which causes the	output
       to be a dynamically linked library (DLL)	instead	of a normal
       executable.  You	should name the	output "*.dll" when you	use this
       option.	In addition, the linker	fully supports the standard "*.def"
       files, which may	be specified on	the linker command line	like an	object
       file (in	fact, it should	precede	archives it exports symbols from, to
       ensure that they	get linked in, just like a normal object file).

       In addition to the options common to all	targets, the i386 PE linker
       support additional command line options that are	specific to the	i386
       PE target.  Options that	take values may	be separated from their	values
       by either a space or an equals sign.

       --add-stdcall-alias
	   If given, symbols with a stdcall suffix (@nn) will be exported as-
	   is and also with the	suffix stripped.  [This	option is specific to
	   the i386 PE targeted	port of	the linker]

       --base-file file
	   Use file as the name	of a file in which to save the base addresses
	   of all the relocations needed for generating	DLLs with dlltool.
	   [This is an i386 PE specific	option]

       --dll
	   Create a DLL	instead	of a regular executable.  You may also use
	   -shared or specify a	"LIBRARY" in a given ".def" file.  [This
	   option is specific to the i386 PE targeted port of the linker]

       --enable-stdcall-fixup
       --disable-stdcall-fixup
	   If the link finds a symbol that it cannot resolve, it will attempt
	   to do "fuzzy	linking" by looking for	another	defined	symbol that
	   differs only	in the format of the symbol name (cdecl	vs stdcall)
	   and will resolve that symbol	by linking to the match.  For example,
	   the undefined symbol	"_foo" might be	linked to the function
	   "_foo@12", or the undefined symbol "_bar@16"	might be linked	to the
	   function "_bar".  When the linker does this,	it prints a warning,
	   since it normally should have failed	to link, but sometimes import
	   libraries generated from third-party	dlls may need this feature to
	   be usable.  If you specify --enable-stdcall-fixup, this feature is
	   fully enabled and warnings are not printed.	If you specify
	   --disable-stdcall-fixup, this feature is disabled and such
	   mismatches are considered to	be errors.  [This option is specific
	   to the i386 PE targeted port	of the linker]

       --export-all-symbols
	   If given, all global	symbols	in the objects used to build a DLL
	   will	be exported by the DLL.	 Note that this	is the default if
	   there otherwise wouldn't be any exported symbols.  When symbols are
	   explicitly exported via DEF files or	implicitly exported via
	   function attributes,	the default is to not export anything else
	   unless this option is given.	 Note that the symbols "DllMain@12",
	   "DllEntryPoint@0", "DllMainCRTStartup@12", and "impure_ptr" will
	   not be automatically	exported.  Also, symbols imported from other
	   DLLs	will not be re-exported, nor will symbols specifying the DLL's
	   internal layout such	as those beginning with	"_head_" or ending
	   with	"_iname".  In addition,	no symbols from	"libgcc", "libstd++",
	   "libmingw32", or "crtX.o" will be exported.	Symbols	whose names
	   begin with "__rtti_"	or "__builtin_"	will not be exported, to help
	   with	C++ DLLs.  Finally, there is an	extensive list of cygwin-
	   private symbols that	are not	exported (obviously, this applies on
	   when	building DLLs for cygwin targets).  These cygwin-excludes are:
	   "_cygwin_dll_entry@12", "_cygwin_crt0_common@8",
	   "_cygwin_noncygwin_dll_entry@12", "_fmode", "_impure_ptr",
	   "cygwin_attach_dll",	"cygwin_premain0", "cygwin_premain1",
	   "cygwin_premain2", "cygwin_premain3", and "environ".	 [This option
	   is specific to the i386 PE targeted port of the linker]

       --exclude-symbols symbol,symbol,...
	   Specifies a list of symbols which should not	be automatically
	   exported.  The symbol names may be delimited	by commas or colons.
	   [This option	is specific to the i386	PE targeted port of the
	   linker]

       --file-alignment
	   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	the i386 PE targeted port of
	   the linker]

       --heap reserve
       --heap reserve,commit
	   Specify the amount of memory	to reserve (and	optionally commit) to
	   be used as heap for this program.  The default is 1Mb reserved, 4K
	   committed.  [This option is specific	to the i386 PE targeted	port
	   of the linker]

       --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 the i386 PE
	   targeted port of the	linker]

       --kill-at
	   If given, the stdcall suffixes (@nn)	will be	stripped from symbols
	   before they are exported.  [This option is specific to the i386 PE
	   targeted port of the	linker]

       --large-address-aware
	   If given, the appropriate bit in the	"Characteristics" field	of the
	   COFF	header is set to indicate that this executable supports
	   virtual addresses greater than 2 gigabytes.	This should be used in
	   conjunction with the	/3GB or	/USERVA=value megabytes	switch in the
	   "[operating systems]" section of the	BOOT.INI.  Otherwise, this bit
	   has no effect.  [This option	is specific to PE targeted ports of
	   the linker]

       --major-image-version value
	   Sets	the major number of the	"image version".  Defaults to 1.
	   [This option	is specific to the i386	PE targeted port of the
	   linker]

       --major-os-version value
	   Sets	the major number of the	"os version".  Defaults	to 4.  [This
	   option is specific to the i386 PE targeted port of the linker]

       --major-subsystem-version value
	   Sets	the major number of the	"subsystem version".  Defaults to 4.
	   [This option	is specific to the i386	PE targeted port of the
	   linker]

       --minor-image-version value
	   Sets	the minor number of the	"image version".  Defaults to 0.
	   [This option	is specific to the i386	PE targeted port of the
	   linker]

       --minor-os-version value
	   Sets	the minor number of the	"os version".  Defaults	to 0.  [This
	   option is specific to the i386 PE targeted port of the linker]

       --minor-subsystem-version value
	   Sets	the minor number of the	"subsystem version".  Defaults to 0.
	   [This option	is specific to the i386	PE targeted port of the
	   linker]

       --output-def file
	   The linker will create the file file	which will contain a DEF file
	   corresponding to the	DLL the	linker is generating.  This DEF	file
	   (which should be called "*.def") may	be used	to create an import
	   library with	"dlltool" or may be used as a reference	to
	   automatically or implicitly exported	symbols.  [This	option is
	   specific to the i386	PE targeted port of the	linker]

       --out-implib file
	   The linker will create the file file	which will contain an import
	   lib corresponding to	the DLL	the linker is generating. This import
	   lib (which should be	called "*.dll.a" or "*.a" may be used to link
	   clients against the generated DLL; this behaviour makes it possible
	   to skip a separate "dlltool"	import library creation	step.  [This
	   option is specific to the i386 PE targeted port of the linker]

       --enable-auto-image-base
	   Automatically choose	the image base for DLLs, unless	one is
	   specified using the "--image-base" argument.	 By using a hash
	   generated from the dllname to create	unique image bases for each
	   DLL,	in-memory collisions and relocations which can delay program
	   execution are avoided.  [This option	is specific to the i386	PE
	   targeted port of the	linker]

       --disable-auto-image-base
	   Do not automatically	generate a unique image	base.  If there	is no
	   user-specified image	base ("--image-base") then use the platform
	   default.  [This option is specific to the i386 PE targeted port of
	   the linker]

       --dll-search-prefix string
	   When	linking	dynamically to a dll without an	import library,	search
	   for "<string><basename>.dll"	in preference to "lib<basename>.dll".
	   This	behaviour allows easy distinction between DLLs built for the
	   various "subplatforms": native, cygwin, uwin, pw, etc.  For
	   instance, cygwin DLLs typically use "--dll-search-prefix=cyg".
	   [This option	is specific to the i386	PE targeted port of the
	   linker]

       --enable-auto-import
	   Do sophisticated linking of "_symbol" to "__imp__symbol" for	DATA
	   imports from	DLLs, and create the necessary thunking	symbols	when
	   building the	import libraries with those DATA exports. Note:	Use of
	   the 'auto-import' extension will cause the text section of the
	   image file to be made writable. This	does not conform to the	PE-
	   COFF	format specification published by Microsoft.

	   Using 'auto-import' generally will 'just work' -- but sometimes you
	   may see this	message:

	   "variable '<var>' can't be auto-imported. Please read the
	   documentation for ld's "--enable-auto-import" for details."

	   This	message	occurs when some (sub)expression accesses an address
	   ultimately given by the sum of two constants	(Win32 import tables
	   only	allow one).  Instances where this may occur include accesses
	   to member fields of struct variables	imported from a	DLL, as	well
	   as using a constant index into an array variable imported from a
	   DLL.	 Any multiword variable	(arrays, structs, long long, etc) may
	   trigger this	error condition.  However, regardless of the exact
	   data	type of	the offending exported variable, ld will always	detect
	   it, issue the warning, and exit.

	   There are several ways to address this difficulty, regardless of
	   the data type of the	exported variable:

	   One way is to use --enable-runtime-pseudo-reloc switch. This	leaves
	   the task of adjusting references in your client code	for runtime
	   environment,	so this	method works only when runtime environment
	   supports this feature.

	   A second solution is	to force one of	the 'constants'	to be a
	   variable -- that is,	unknown	and un-optimizable at compile time.
	   For arrays, there are two possibilities: a) make the	indexee	(the
	   array's address) a variable,	or b) make the 'constant' index	a
	   variable.  Thus:

		   extern type extern_array[];
		   extern_array[1] -->
		      {	volatile type *t=extern_array; t[1] }

	   or

		   extern type extern_array[];
		   extern_array[1] -->
		      {	volatile int t=1; extern_array[t] }

	   For structs (and most other multiword data types) the only option
	   is to make the struct itself	(or the	long long, or the ...)
	   variable:

		   extern struct s extern_struct;
		   extern_struct.field -->
		      {	volatile struct	s *t=&extern_struct; t->field }

	   or

		   extern long long extern_ll;
		   extern_ll -->
		     { volatile	long long * local_ll=&extern_ll; *local_ll }

	   A third method of dealing with this difficulty is to	abandon
	   'auto-import' for the offending symbol and mark it with
	   "__declspec(dllimport)".  However, in practise that requires	using
	   compile-time	#defines to indicate whether you are building a	DLL,
	   building client code	that will link to the DLL, or merely
	   building/linking to a static	library.   In making the choice
	   between the various methods of resolving the	'direct	address	with
	   constant offset' problem, you should	consider typical real-world
	   usage:

	   Original:

		   --foo.h
		   extern int arr[];
		   --foo.c
		   #include "foo.h"
		   void	main(int argc, char **argv){
		     printf("%d\n",arr[1]);
		   }

	   Solution 1:

		   --foo.h
		   extern int arr[];
		   --foo.c
		   #include "foo.h"
		   void	main(int argc, char **argv){
		     /*	This workaround	is for win32 and cygwin; do not	"optimize" */
		     volatile int *parr	= arr;
		     printf("%d\n",parr[1]);
		   }

	   Solution 2:

		   --foo.h
		   /* Note: auto-export	is assumed (no __declspec(dllexport)) */
		   #if (defined(_WIN32)	|| defined(__CYGWIN__))	&& \
		     !(defined(FOO_BUILD_DLL) || defined(FOO_STATIC))
		   #define FOO_IMPORT __declspec(dllimport)
		   #else
		   #define FOO_IMPORT
		   #endif
		   extern FOO_IMPORT int arr[];
		   --foo.c
		   #include "foo.h"
		   void	main(int argc, char **argv){
		     printf("%d\n",arr[1]);
		   }

	   A fourth way	to avoid this problem is to re-code your library to
	   use a functional interface rather than a data interface for the
	   offending variables (e.g. set_foo() and get_foo() accessor
	   functions).	[This option is	specific to the	i386 PE	targeted port
	   of the linker]

       --disable-auto-import
	   Do not attempt to do	sophisticated linking of "_symbol" to
	   "__imp__symbol" for DATA imports from DLLs.	[This option is
	   specific to the i386	PE targeted port of the	linker]

       --enable-runtime-pseudo-reloc
	   If your code	contains expressions described in --enable-auto-import
	   section, that is, DATA imports from DLL with	non-zero offset, this
	   switch will create a	vector of 'runtime pseudo relocations' which
	   can be used by runtime environment to adjust	references to such
	   data	in your	client code.  [This option is specific to the i386 PE
	   targeted port of the	linker]

       --disable-runtime-pseudo-reloc
	   Do not create pseudo	relocations for	non-zero offset	DATA imports
	   from	DLLs.  This is the default.  [This option is specific to the
	   i386	PE targeted port of the	linker]

       --enable-extra-pe-debug
	   Show	additional debug info related to auto-import symbol thunking.
	   [This option	is specific to the i386	PE targeted port of the
	   linker]

       --section-alignment
	   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	the i386 PE targeted port of
	   the linker]

       --stack reserve
       --stack reserve,commit
	   Specify the amount of memory	to reserve (and	optionally commit) to
	   be used as stack for	this program.  The default is 2Mb reserved, 4K
	   committed.  [This option is specific	to the i386 PE targeted	port
	   of the linker]

       --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",
	   and "xbox".	You may	optionally set the subsystem version also.
	   Numeric values are also accepted for	which.	[This option is
	   specific to the i386	PE targeted port of the	linker]

       The 68HC11 and 68HC12 linkers support specific options to control the
       memory bank switching mapping and trampoline code generation.

       --no-trampoline
	   This	option disables	the generation of trampoline. By default a
	   trampoline is generated for each far	function which is called using
	   a "jsr" instruction (this happens when a pointer to a far function
	   is taken).

       --bank-window name
	   This	option indicates to the	linker the name	of the memory region
	   in the MEMORY specification that describes the memory bank window.
	   The definition of such region is then used by the linker to compute
	   paging and addresses	within the memory window.

ENVIRONMENT
       You can change the behaviour of ld with the environment variables
       "GNUTARGET", "LDEMULATION" and "COLLECT_NO_DEMANGLE".

       "GNUTARGET" determines the input-file object format if you don't	use -b
       (or its synonym --format).  Its value should be one of the BFD names
       for an input format.  If	there is no "GNUTARGET"	in the environment, ld
       uses the	natural	format of the target. If "GNUTARGET" is	set to
       "default" then BFD attempts to discover the input format	by examining
       binary input files; this	method often succeeds, but there are potential
       ambiguities, since there	is no method of	ensuring that the magic	number
       used to specify object-file formats is unique.  However,	the
       configuration procedure for BFD on each system places the conventional
       format for that system first in the search-list,	so ambiguities are
       resolved	in favor of convention.

       "LDEMULATION" determines	the default emulation if you don't use the -m
       option.	The emulation can affect various aspects of linker behaviour,
       particularly the	default	linker script.	You can	list the available
       emulations with the --verbose or	-V options.  If	the -m option is not
       used, and the "LDEMULATION" environment variable	is not defined,	the
       default emulation depends upon how the linker was configured.

       Normally, the linker will default to demangling symbols.	 However, if
       "COLLECT_NO_DEMANGLE" is	set in the environment,	then it	will default
       to not demangling symbols.  This	environment variable is	used in	a
       similar fashion by the "gcc" linker wrapper program.  The default may
       be overridden by	the --demangle and --no-demangle options.

SEE ALSO
       ar(1), nm(1), objcopy(1), objdump(1), readelf(1)	and the	Info entries
       for binutils and	ld.

COPYRIGHT
       Copyright (c) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002,
       2003, 2004, 2005, 2006, 2007 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 1.1 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-2.17.50		  2010-10-30				 LD(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ENVIRONMENT | SEE ALSO | COPYRIGHT

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