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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 exe-
       cution  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 stan-
       dard, 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 descrip-
       tions below.

       Non-option arguments are object files  or  archives  which  are	to  be
       linked  together.   They	 may follow, precede, or be mixed in with com-
       mand-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 speci-
       fied, 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 aug-
       ments  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 imme-
       diately	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  charac-
	   ter	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  "GNUTAR-
	   GET".

	   You	can also define the input format from a script, using the com-
	   mand "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 doc-
	   umentation.	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  sym-
	   bol	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  nor-
	   mally  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 for-
	   mat.

       -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	auxil-
	   iary 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 debug-
	   ging 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  pro-
	   vided by the object name.

	   Some	 older	linkers	 used  the  -F option throughout a compilation
	   toolchain for specifying object-file format for both input and out-
	   put	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 regis-
	   ter	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.

       -larchive
       --library=archive
	   Add archive file archive to the list of files to link.  This option
	   may	be used any number of times.  ld will search its path-list for
	   occurrences of "libarchive.a" for every archive specified.

	   On systems which support shared libraries, ld may also  search  for
	   libraries  with  extensions	other than ".a".  Specifically, on ELF
	   and SunOS systems, ld will search a directory for a library with an
	   extension  of  ".so"	 before searching for one with an extension of
	   ".a".  By convention, a ".so" extension indicates a shared library.

	   The	linker will search an archive only once, at the location where
	   it is specified on the command line.	 If the archive defines a sym-
	   bol	which  was  undefined in some object which appeared before the
	   archive on the command line, the linker will include the  appropri-
	   ate	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.	  How-
	   ever,  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 speci-
	   fied on the command line are searched before the  default  directo-
	   ries.   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	emula-
	   tions 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:

	   *   Where object files are mapped into memory.

	   *   How common symbols are allocated.

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

	   *   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 circum-
	       stances 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 proba-
	   bly 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 fol-
	   lowed 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.

       -u symbol
       --undefined=symbol
	   Force  symbol to be entered in the output file as an undefined sym-
	   bol.	 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 sys-
	   tem-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 run-
	       time 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 unde-
	   fined 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  sym-
	   bol	referred  to  by an object in an archive that appears later on
	   the command line, the linker would not be able to resolve that ref-
	   erence.   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  men-
	   tioned on the command line after the --as-needed option.  Normally,
	   the linker will add a DT_NEEDED tag for each dynamic	 library  men-
	   tioned  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 regu-
	   lar 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 plat-
	   forms 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	 over-
	   ride the definition within the shared library.  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  defini-
	   tion within the shared library, or creating dynamically linked exe-
	   cutables 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-cpp-typeinfo
	   Provide  the	 builtin dynamic list for C++ runtime type identifica-
	   tion.

       --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  pro-
	   duce 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 gen-
	   erated, the cross reference table is printed to the map file.  Oth-
	   erwise, 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  Com-
	   mon	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, con-
	   sider 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.  Dif-
	   ferent 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 col-
	   lection 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 out-
	   put 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	 actu-
	   ally	 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  sym-
	   bols.

       --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 unver-
	   sioned exported symbols.

       --default-imported-symver
	   Create and use a default symbol version  (the  soname)  for	unver-
	   sioned 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 endi-
	   annesses.  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-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 encoun-
	   ters 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 sup-
	   ported 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 gradu-
	   ally, to conserve run-time memory.

	   --retain-symbols-file does not discard undefined symbols,  or  sym-
	   bols 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 fol-
	   lowed 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  run-
	       time,  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	direc-
	       tories 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 pat-
	   terns 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 sin-
	   gle output section in the file contains  more  than	count  reloca-
	   tions.   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 reloca-
	   tions 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  redistribu-
	   tion, so if a single input section contains more than count reloca-
	   tions 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  con-
	   figure-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	possi-
	   ble 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 con-
	   trolled 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	 typi-
	   cally  used	when  creating	shared libraries to specify additional
	   information about the version hierarchy for the library being  cre-
	   ated.   This	 option is only meaningful on ELF platforms which sup-
	   port 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  sym-
	       bols  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 differ-
	       ent sizes, it picks the largest size.  The linker turns a  com-
	       mon  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 defi-
	       nition 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  sym-
	       bol.

		       <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 multi-
	   ple global pointer values in order to be able to address all possi-
	   ble	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 mod-
	   ule 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  sec-
	   tion.  The address will only be changed if it not explicitly speci-
	   fied; 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 sym-
	   bol 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  cre-
	   ated.  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 exe-
       cutable.	 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 --dis-
	   able-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 func-
	   tion attributes, the default is to not export anything else	unless
	   this	 option is given.  Note that the symbols "DllMain@12", "DllEn-
	   tryPoint@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-pri-
	   vate 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_noncyg-
	   win_dll_entry@12",  "_fmode",  "_impure_ptr",  "cygwin_attach_dll",
	   "cygwin_premain0",  "cygwin_premain1",   "cygwin_premain2",	 "cyg-
	   win_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	 over-
	   lap	any  other dlls.  The default is 0x400000 for executables, and
	   0x10000000 for dlls.	 [This option is specific to the i386 PE  tar-
	   geted 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  vir-
	   tual	 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 spe-
	   cific 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 speci-
	   fied using the "--image-base" argument.  By using a hash  generated
	   from the dllname to create unique image bases for each DLL, in-mem-
	   ory 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 documen-
	   tation 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	 vari-
	   able	 --  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 ...) vari-
	   able:

		   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	build-
	   ing/linking to a static library.   In making the choice between the
	   various methods of resolving the 'direct address with constant off-
	   set' 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 func-
	   tions).  [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  spe-
	   cific 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 spe-
	   cific 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 "GNU-
       TARGET", "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 configura-
       tion 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 sim-
       ilar 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 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-2.17.50.0.6-26.el5	  2013-10-01				 LD(1)
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