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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.  Specifying a script in this
       way merely augments the main linker script, with the extra commands
       placed after the main script; use the -T option to replace the default
       linker script entirely, but note the effect of the "INSERT" command.

       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,--start-group foo.o bar.o -Wl,--end-group

       This is important, because otherwise the compiler driver program may
       silently drop the linker options, resulting in a bad link.  Confusion
       may also arise when passing options that require values through a
       driver, as the use of a space between option and argument acts as a
       separator, and causes the driver to pass only the option to the linker
       and the argument to the compiler.  In this case, it is simplest to use
       the joined forms of both single- and multiple-letter options, such as:

		 gcc foo.o bar.o -Wl,-eENTRY -Wl,-Map=a.map

       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.

       -a keyword
	   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.

       --audit AUDITLIB
	   Adds AUDITLIB to the "DT_AUDIT" entry of the dynamic section.
	   AUDITLIB is not checked for existence, nor will it use the
	   DT_SONAME specified in the library.	If specified multiple times
	   "DT_AUDIT" will contain a colon separated list of audit interfaces
	   to use. If the linker finds an object with an audit entry while
	   searching for shared libraries, it will add a corresponding
	   "DT_DEPAUDIT" entry in the output file.  This option is only
	   meaningful on ELF platforms supporting the rtld-audit interface.

       -A architecture
       --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.

       --depaudit AUDITLIB
       -P AUDITLIB
	   Adds AUDITLIB to the "DT_DEPAUDIT" entry of the dynamic section.
	   AUDITLIB is not checked for existence, nor will it use the
	   DT_SONAME specified in the library.	If specified multiple times
	   "DT_DEPAUDIT" will contain a colon separated list of audit
	   interfaces to use.  This option is only meaningful on ELF platforms
	   supporting the rtld-audit interface.	 The -P option is provided for
	   Solaris compatibility.

       -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.

       --exclude-modules-for-implib module,module,...
	   Specifies a list of object files or archive members, from which
	   symbols should not be automatically exported, but which should be
	   copied wholesale into the import library being generated during the
	   link.  The module names may be delimited by commas or colons, and
	   must match exactly the filenames used by ld to open the files; for
	   archive members, this is simply the member name, but for object
	   files the name listed must include and match precisely any path
	   used to specify the input file on the linker's command-line.	 This
	   option is available only for the i386 PE targeted port of the
	   linker.  Symbols explicitly listed in a .def file are still
	   exported, regardless of this option.

       -E
       --export-dynamic
       --no-export-dynamic
	   When creating a dynamically linked executable, using the -E option
	   or the --export-dynamic option causes the linker to 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 either of these options (or use the
	   --no-export-dynamic option to restore the default behavior), 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.

	   Note that this option is specific to ELF targeted ports.  PE
	   targets support a similar function to export all symbols from a DLL
	   or EXE; see the description of --export-all-symbols below.

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

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

       -f name
       --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.

       -G value
       --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 ELF that support putting large and small objects into
	   different sections.	This is ignored for other object file formats.

       -h name
       -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.

       -l namespec
       --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, otherwise 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.

       -L searchdir
       --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.  -L options do not affect
	   how ld searches for a linker script unless -T option is specified.

	   If searchdir begins with "=", then the "=" will be replaced by the
	   sysroot prefix, controlled by the --sysroot option, or 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.

       -m emulation
	   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 disable linking against
	   shared libraries.  If the output format supports Unix style magic
	   numbers, mark the output as "NMAGIC".

       -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.  At the
	   moment this option only affects ELF shared library generation.
	   Future releases of the linker may make more use of this option.
	   Also currently there is no difference in the linker's behaviour for
	   different non-zero values of this option.  Again this may change
	   with future releases.

       --push-state
	   The --push-state allows to preserve the current state of the flags
	   which govern the input file handling so that they can all be
	   restored with one corresponding --pop-state option.

	   The option which are covered are: -Bdynamic, -Bstatic, -dn, -dy,
	   -call_shared, -non_shared, -static, -N, -n, --whole-archive,
	   --no-whole-archive, -r, -Ur, --copy-dt-needed-entries,
	   --no-copy-dt-needed-entries, --as-needed, --no-as-needed, and -a.

	   One target for this option are specifications for pkg-config.  When
	   used with the --libs option all possibly needed libraries are
	   listed and then possibly linked with all the time.  It is better to
	   return something as follows:

		   -Wl,--push-state,--as-needed -libone -libtwo -Wl,--pop-state

	   Undoes the effect of --push-state, restores the previous values of
	   the flags governing input file handling.

       -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.

	   If this option is being used to force additional modules to be
	   pulled into the link, and if it is an error for the symbol to
	   remain undefined, then the option --require-defined should be used
	   instead.

       --require-defined=symbol
	   Require that symbol is defined in the output file.  This option is
	   the same as option --undefined except that if symbol is not defined
	   in the output file then the linker will issue an error and exit.
	   The same effect can be achieved in a linker script by using
	   "EXTERN", "ASSERT" and "DEFINED" together.  This option can be used
	   multiple times to require additional symbols.

       -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.

       --orphan-handling=MODE
	   Control how orphan sections are handled.  An orphan section is one
	   not specifically mentioned in a linker script.

	   MODE can have any of the following values:

	   "place"
	       Orphan sections are placed into a suitable output section
	       following the strategy described in Orphan Sections.  The
	       option --unique also effects how sections are placed.

	   "discard"
	       All orphan sections are discarded, by placing them in the
	       /DISCARD/ section.

	   "warn"
	       The linker will place the orphan section as for "place" and
	       also issue a warning.

	   "error"
	       The linker will exit with an error if any orphan section is
	       found.

	   The default if --orphan-handling is not given is "place".

       --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.

	   common
	       Generate common symbols with the STT_COMMON type druing a
	       relocatable link.

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

	   execstack
	       Marks the object as requiring executable stack.

	   global
	       This option is only meaningful when building a shared object.
	       It makes the symbols defined by this shared object available
	       for symbol resolution of subsequently loaded libraries.

	   globalaudit
	       This option is only meaningful when building a dynamic
	       executable.  This option marks the executable as requiring
	       global auditing by setting the "DF_1_GLOBAUDIT" bit in the
	       "DT_FLAGS_1" dynamic tag.  Global auditing requires that any
	       auditing library defined via the --depaudit or -P command line
	       options be run for all dynamic objects loaded by the
	       application.

	   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.

	   nocommon
	       Generate common symbols with the STT_OBJECT type druing a
	       relocatable link.

	   nocopyreloc
	       Disable linker generated .dynbss variables used in place of
	       variables defined in shared libraries.  May result in dynamic
	       text relocations.

	   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.

	   text
	       Treat DT_TEXTREL in shared object as error.

	   notext
	       Don't treat DT_TEXTREL in shared object as error.

	   textoff
	       Don't treat DT_TEXTREL in shared object as error.

	   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.

	   stack-size=value
	       Specify a stack size for in an ELF "PT_GNU_STACK" segment.
	       Specifying zero will override any default non-zero sized
	       "PT_GNU_STACK" segment creation.

	   bndplt
	       Always generate BND prefix in PLT entries. Supported for
	       Linux/x86_64.

	   noextern-protected-data
	       Don't treat protected data symbol as external when building
	       shared library.	This option overrides linker backend default.
	       It can be used to workaround incorrect relocations against
	       protected data symbols generated by compiler.  Updates on
	       protected data symbols by another module aren't visible to the
	       resulting shared library.  Supported for i386 and x86-64.

	   nodynamic-undefined-weak
	       Don't treat undefined weak symbols as dynamic when building
	       executable.  This option overrides linker backend default.  It
	       can be used to avoid dynamic relocations against undefined weak
	       symbols in executable.  Supported for i386 and x86-64.

	   noreloc-overflow
	       Disable relocation overflow check.  This can be used to disable
	       relocation overflow check if there will be no dynamic
	       relocation overflow at run-time.	 Supported for x86_64.

	   call-nop=prefix-addr
	   call-nop=prefix-nop
	   call-nop=suffix-nop
	   call-nop=prefix-byte
	   call-nop=suffix-byte
	       Specify the 1-byte "NOP" padding when transforming indirect
	       call to a locally defined function, foo, via its GOT slot.
	       call-nop=prefix-addr generates "0x67 call foo".
	       call-nop=prefix-nop generates "0x90 call foo".
	       call-nop=suffix-nop generates "call foo 0x90".
	       call-nop=prefix-byte generates "byte call foo".
	       call-nop=suffix-byte generates "call foo byte".	Supported for
	       i386 and x86_64.

	   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 or not.  --as-needed causes a DT_NEEDED
	   tag to only be emitted for a library that at that point in the link
	   satisfies a non-weak undefined symbol reference from a regular
	   object file or, if the library is not found in the DT_NEEDED lists
	   of other needed libraries, a non-weak undefined symbol reference
	   from another needed dynamic library.	 Object files or libraries
	   appearing on the command line after the library in question do not
	   affect whether the library is seen as needed.  This is similar to
	   the rules for extraction of object files from archives.
	   --no-as-needed restores the default behaviour.

       --add-needed
       --no-add-needed
	   These two options have been deprecated because of the similarity of
	   their names to the --as-needed and --no-as-needed options.  They
	   have been replaced by --copy-dt-needed-entries and
	   --no-copy-dt-needed-entries.

       -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 can
	   also be used with the --export-dynamic option, when creating a
	   position independent executable, to bind references to global
	   symbols to the definition within the executable.  This option is
	   only meaningful on ELF platforms which support shared libraries and
	   position independent executables.

       -Bsymbolic-functions
	   When creating a shared library, bind references to global function
	   symbols to the definition within the shared library, if any.	 This
	   option can also be used with the --export-dynamic option, when
	   creating a position independent executable, to bind references to
	   global function symbols to the definition within the executable.
	   This option is only meaningful on ELF platforms which support
	   shared libraries and position independent executables.

       --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.  Section overlap is not usually checked for
	   relocatable links.  You can force checking in that case by using
	   the --check-sections option.

       --copy-dt-needed-entries
       --no-copy-dt-needed-entries
	   This option affects the treatment of dynamic libraries referred to
	   by DT_NEEDED tags inside ELF dynamic libraries mentioned on the
	   command line.  Normally the linker won't add a DT_NEEDED tag to the
	   output binary for each library mentioned in a DT_NEEDED tag in an
	   input dynamic library.  With --copy-dt-needed-entries specified on
	   the command line however any dynamic libraries that follow it will
	   have their DT_NEEDED entries added.	The default behaviour can be
	   restored with --no-copy-dt-needed-entries.

	   This option also has an effect on the resolution of symbols in
	   dynamic libraries.  With --copy-dt-needed-entries dynamic libraries
	   mentioned on the command line will be recursively searched,
	   following their DT_NEEDED tags to other libraries, in order to
	   resolve symbols required by the output binary.  With the default
	   setting however the searching of dynamic libraries that follow it
	   will stop with the dynamic library itself.  No DT_NEEDED links will
	   be traversed to resolve symbols.

       --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.	If the symbol is defined as a common
	   value then any files where this happens appear next.	 Finally any
	   files that reference the symbol are listed.

       --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.

       -Ifile
       --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.

       --no-dynamic-linker
	   When producing an executable file, omit the request for a dynamic
	   linker to be used at load-time.  This is only meaningful for ELF
	   executables that contain dynamic relocations, and usually requires
	   entry point code that is capable of processing these relocations.

       --fatal-warnings
       --no-fatal-warnings
	   Treat all warnings as errors.  The default behaviour can be
	   restored with the option --no-fatal-warnings.

       --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.	The default behaviour
	   (of not performing this garbage collection) can be restored by
	   specifying --no-gc-sections on the command line.  Note that garbage
	   collection for COFF and PE format targets is supported, but the
	   implementation is currently considered to be experimental.

	   --gc-sections decides which input sections are used by examining
	   symbols and relocations.  The section containing the entry symbol
	   and all sections containing symbols undefined on the command-line
	   will be kept, as will sections containing symbols referenced by
	   dynamic objects.  Note that when building shared libraries, the
	   linker must assume that any visible symbol is referenced.  Once
	   this initial set of sections has been determined, the linker
	   recursively marks as used any section referenced by their
	   relocations.	 See --entry and --undefined.

	   This option can be set when doing a partial link (enabled with
	   option -r).	In this case the root of symbols kept must be
	   explicitly specified either by an --entry or --undefined option or
	   by a "ENTRY" command in the linker script.

       --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.

       --print-output-format
	   Print the name of the default output format (perhaps influenced by
	   other command-line options).	 This is the string that would appear
	   in an "OUTPUT_FORMAT" linker script command.

       --print-memory-usage
	   Print used size, total size and used size of memory regions created
	   with the MEMORY command.  This is useful on embedded targets to
	   have a quick view of amount of free memory.	The format of the
	   output has one headline and one line per region.  It is both human
	   readable and easily parsable by tools.  Here is an example of an
	   output:

		   Memory region	 Used Size  Region Size	 %age Used
				ROM:	    256 KB	   1 MB	    25.00%
				RAM:	      32 B	   2 GB	     0.00%

       --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 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 default behaviour is to report errors for any undefined symbols
	   referenced in shared libraries if the linker is being used to
	   create an executable, but to allow them if the linker is being used
	   to create a shared library.

	   The reasons for allowing undefined symbol references in shared
	   libraries specified at link time are that:

	   o   A shared library specified at link time may not be the same as
	       the one that is available at load time, so the symbol might
	       actually be resolvable at load time.

	   o   There are some operating systems, eg BeOS and HPPA, where
	       undefined symbols in shared libraries are normal.

	       The BeOS kernel for example patches shared libraries at load
	       time to select whichever function is most appropriate for the
	       current architecture.  This is used, for example, to
	       dynamically select an appropriate memset function.

       --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
       --no-relax
	   An option with machine dependent effects.  This option is only
	   supported on a few targets.

	   On some platforms the --relax option performs target specific,
	   global optimizations that become possible when the linker resolves
	   addressing in the program, such as relaxing address modes,
	   synthesizing new instructions, selecting shorter version of current
	   instructions, and combining constant values.

	   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.

	   On platforms where --relax is accepted the option --no-relax can be
	   used to disable the feature.

       --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 path 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, for native linkers, if the -rpath and
	       -rpath-link options were not used, search the contents of the
	       environment variable "LD_RUN_PATH".

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

	   5.  For a native linker, search 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
       --sort-common=ascending
       --sort-common=descending
	   This option tells ld to sort the common symbols by alignment in
	   ascending or descending order when it places them in the
	   appropriate output sections.	 The symbol alignments considered are
	   sixteen-byte or larger, eight-byte, four-byte, two-byte, and one-
	   byte. This is to prevent gaps between symbols due to alignment
	   constraints.	 If no sorting order is specified, then descending
	   order is assumed.

       --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.

       -Ttext-segment=org
	   When creating an ELF executable, it will set the address of the
	   first byte of the text segment.

       -Trodata-segment=org
	   When creating an ELF executable or shared object for a target where
	   the read-only data is in its own segment separate from the
	   executable text, it will set the address of the first byte of the
	   read-only data segment.

       -Tldata-segment=org
	   When creating an ELF executable or shared object for x86-64 medium
	   memory model, it will set the address of the first byte of the
	   ldata segment.

       --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[=NUMBER]
	   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. If the optional
	   NUMBER argument > 1, plugin symbol status will also be displayed.

       --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 fully supported on ELF platforms
	   which support shared libraries; see VERSION.	 It is partially
	   supported on PE platforms, which can use version scripts to filter
	   symbol visibility in auto-export mode: any symbols marked local in
	   the version script will not be exported.

       --warn-common
	   Warn when a common symbol is combined with another common symbol or
	   with a symbol definition.  Unix linkers allow this somewhat sloppy
	   practice, 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 practice, 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-alternate-em
	   Warn if an object has alternate ELF machine code.

       --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.

       --no-ld-generated-unwind-info
	   Request creation of ".eh_frame" unwind info for linker generated
	   code sections like PLT.  This option is on by default if linker
	   generated unwind info is supported.

       --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 new dynamic tags will be created as needed
	   and older dynamic tags will be omitted.  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".

       --compress-debug-sections=none
       --compress-debug-sections=zlib
       --compress-debug-sections=zlib-gnu
       --compress-debug-sections=zlib-gabi
	   On ELF platforms , these options control how DWARF debug sections
	   are compressed using zlib.  --compress-debug-sections=none doesn't
	   compress DWARF debug sections.  --compress-debug-sections=zlib-gnu
	   compresses DWARF debug sections and rename debug section names to
	   begin with .zdebug instead of .debug.
	   --compress-debug-sections=zlib and
	   --compress-debug-sections=zlib-gabi compress DWARF debug sections
	   with SHF_COMPRESSED from the ELF ABI.  The default behaviour varies
	   depending upon the target involved and the configure options used
	   to build the toolchain.  The default can be determined by examing
	   the output from the linker's --help option.

       --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.

       --build-id
       --build-id=style
	   Request the creation of a ".note.gnu.build-id" ELF note section or
	   a ".buildid" COFF section.  The contents of the note are unique
	   bits identifying this linked file.  style can be "uuid" to use 128
	   random bits, "sha1" to use a 160-bit SHA1 hash on the normative
	   parts of the output contents, "md5" to use a 128-bit MD5 hash on
	   the normative parts of the output contents, or "0xhexstring" to use
	   a chosen bit string specified as an even number of hexadecimal
	   digits ("-" and ":" characters between digit pairs are ignored).
	   If style is omitted, "sha1" is used.

	   The "md5" and "sha1" styles produces an identifier that is always
	   the same in an identical output file, but will be unique among all
	   nonidentical output files.  It is not intended to be compared as a
	   checksum for the file's contents.  A linked file may be changed
	   later by other tools, but the build ID bit string identifying the
	   original linked file does not change.

	   Passing "none" for style disables the setting from any "--build-id"
	   options earlier on the command line.

       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-long-section-names
       --disable-long-section-names
	   The PE variants of the COFF object format add an extension that
	   permits the use of section names longer than eight characters, the
	   normal limit for COFF.  By default, these names are only allowed in
	   object files, as fully-linked executable images do not carry the
	   COFF string table required to support the longer names.  As a GNU
	   extension, it is possible to allow their use in executable images
	   as well, or to (probably pointlessly!)  disallow it in object
	   files, by using these two options.  Executable images generated
	   with these long section names are slightly non-standard, carrying
	   as they do a string table, and may generate confusing output when
	   examined with non-GNU PE-aware tools, such as file viewers and
	   dumpers.  However, GDB relies on the use of PE long section names
	   to find Dwarf-2 debug information sections in an executable image
	   at runtime, and so if neither option is specified on the command-
	   line, ld will enable long section names, overriding the default and
	   technically correct behaviour, when it finds the presence of debug
	   information while linking an executable image and not stripping
	   symbols.  [This option is valid for all PE targeted ports 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]

       --leading-underscore
       --no-leading-underscore
	   For most targets default symbol-prefix is an underscore and is
	   defined in target's description. By this option it is possible to
	   disable/enable the default underscore symbol-prefix.

       --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]

       --exclude-all-symbols
	   Specifies no symbols should be automatically exported.  [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 number of bytes 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]

       --disable-large-address-aware
	   Reverts the effect of a previous --large-address-aware option.
	   This is useful if --large-address-aware is always set by the
	   compiler driver (e.g. Cygwin gcc) and the executable does not
	   support virtual addresses greater than 2 gigabytes.	[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
       --enable-auto-image-base=value
	   Automatically choose the image base for DLLs, optionally starting
	   with base value, 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.

	   Note - use of the 'auto-import' extension will also cause read only
	   data which would normally be placed into the .rdata section to be
	   placed into the .data section instead.  This is in order to work
	   around a problem with consts that is described here:
	   http://www.cygwin.com/ml/cygwin/2004-09/msg01101.html

	   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 practice 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 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 number of bytes 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 following options set flags in the "DllCharacteristics" field
	   of the PE file header: [These options are specific to PE targeted
	   ports of the linker]

       --high-entropy-va
	   Image is compatible with 64-bit address space layout randomization
	   (ASLR).

       --dynamicbase
	   The image base address may be relocated using address space layout
	   randomization (ASLR).  This feature was introduced with MS Windows
	   Vista for i386 PE targets.

       --forceinteg
	   Code integrity checks are enforced.

       --nxcompat
	   The image is compatible with the Data Execution Prevention.	This
	   feature was introduced with MS Windows XP SP2 for i386 PE targets.

       --no-isolation
	   Although the image understands isolation, do not isolate the image.

       --no-seh
	   The image does not use SEH. No SE handler may be called from this
	   image.

       --no-bind
	   Do not bind this image.

       --wdmdriver
	   The driver uses the MS Windows Driver Model.

       --tsaware
	   The image is Terminal Server aware.

       --insert-timestamp
       --no-insert-timestamp
	   Insert a real timestamp into the image.  This is the default
	   behaviour as it matches legacy code and it means that the image
	   will work with other, proprietary tools.  The problem with this
	   default is that it will result in slightly different images being
	   produced each time the same sources are linked.  The option
	   --no-insert-timestamp can be used to insert a zero value for the
	   timestamp, this ensuring that binaries produced from identical
	   sources will compare identically.

       The C6X uClinux target uses a binary format called DSBT to support
       shared libraries.  Each shared library in the system needs to have a
       unique index; all executables use an index of 0.

       --dsbt-size size
	   This option sets the number of entries in the DSBT of the current
	   executable or shared library to size.  The default is to create a
	   table with 64 entries.

       --dsbt-index index
	   This option sets the DSBT index of the current executable or shared
	   library to index.  The default is 0, which is appropriate for
	   generating executables.  If a shared library is generated with a
	   DSBT index of 0, the "R_C6000_DSBT_INDEX" relocs are copied into
	   the output file.

	   The --no-merge-exidx-entries switch disables the merging of
	   adjacent exidx entries in frame unwind info.

       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.

       The following options are supported to control handling of GOT
       generation when linking for 68K targets.

       --got=type
	   This option tells the linker which GOT generation scheme to use.
	   type should be one of single, negative, multigot or target.	For
	   more information refer to the Info entry for ld.

       The following options are supported to control microMIPS instruction
       generation when linking for MIPS targets.

       --insn32
       --no-insn32
	   These options control the choice of microMIPS instructions used in
	   code generated by the linker, such as that in the PLT or lazy
	   binding stubs, or in relaxation.  If --insn32 is used, then the
	   linker only uses 32-bit instruction encodings.  By default or if
	   --no-insn32 is used, all instruction encodings are used, including
	   16-bit ones where possible.

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) 1991-2016 Free Software Foundation, Inc.

       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.3 or
       any later version published by the Free Software Foundation; with no
       Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
       Texts.  A copy of the license is included in the section entitled "GNU
       Free Documentation License".



binutils-2.27			  2023-09-13				 LD(1)