# ld

## 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.
    
           **-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.
    
           **--enable-linker-version**
               Enables the "LINKER_VERSION" linker script directive,
               described in **Output Section Data**.  If this directive is used
               in a linker script and this option has been enabled then a
               string containing the linker version will be inserted at the
               current point.
    
               Note - this location of this option on the linker command line
               is significant.  It will only affect linker scripts that come
               after it on the command line, or which are built into the
               linker.
    
           **--disable-linker-version**
               Disables the "LINKER_VERSION" linker script directive, so that
               it does not insert a version string.  This is the default.
    
           **--enable-non-contiguous-regions**
               This option avoids generating an error if an input section
               does not fit a matching output section. The linker tries to
               allocate the input section to subseque nt matching output
               sections, and generates an error only if no output section is
               large enough.  This is useful when several non-contiguous
               memory regions are available and the input section does not
               require a particular one.  The order in which input sections
               are evaluated does not change, for instance:
    
                         MEMORY {
                           MEM1 (rwx) : ORIGIN = 0x1000, LENGTH = 0x14
                           MEM2 (rwx) : ORIGIN = 0x1000, LENGTH = 0x40
                           MEM3 (rwx) : ORIGIN = 0x2000, LENGTH = 0x40
                         }
                         SECTIONS {
                           mem1 : { *(.data.*); } > MEM1
                           mem2 : { *(.data.*); } > MEM2
                           mem3 : { *(.data.*); } > MEM3
                         }
    
                         with input sections:
                         .data.1: size 8
                         .data.2: size 0x10
                         .data.3: size 4
    
                         results in .data.1 affected to mem1, and .data.2 and .data.3
                         affected to mem2, even though .data.3 would fit in mem3.
    
               This option is incompatible with INSERT statements because it
               changes the way input sections are mapped to output sections.
    
           **--enable-non-contiguous-regions-warnings**
               This option enables warnings when
               "--enable-non-contiguous-regions" allows possibly unexpected
               matches in sections mapping, potentially leading to silently
               discarding a section instead of failing because it does not
               fit any output region.
    
           **-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.
    
           **--export-dynamic-symbol=**_glob_
               When creating a dynamically linked executable, symbols
               matching _glob_ will be added to the dynamic symbol table. When
               creating a shared library, references to symbols matching _glob_
               will not be bound to the definitions within the shared
               library. This option is a no-op when creating a shared library
               and **-Bsymbolic** or **--dynamic-list** are not specified. This
               option is only meaningful on ELF platforms which support
               shared libraries.
    
           **--export-dynamic-symbol-list=**_file_
               Specify a **--export-dynamic-symbol** for each pattern in the
               file.  The format of the file is the same as the version node
               without scope and node name.  See **VERSION** for more
               information.
    
           **-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
               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 "=" or $SYSROOT, then this prefix
               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.
    
           [1m--remap-inputs=_pattern_ =_filename_
           [1m--remap-inputs-file=_file_
               These options allow the names of input files to be changed
               before the linker attempts to open them.  The option
               **--remap-inputs=foo.o=bar.o** will cause any attempt to load a
               file called _foo.o_ to instead try to load a file called _bar.o_.
               Wildcard patterns are permitted in the first filename, so
               **--remap-inputs=foo*.o=bar.o** will rename any input file that
               matches _foo*.o_ to _bar.o_.
    
               An alternative form of the option **--remap-inputs-file=filename**
               allows the remappings to be read from a file.  Each line in
               the file can contain a single remapping.  Blank lines are
               ignored.  Anything from a hash character (**#**) to the end of a
               line is considered to be a comment and is also ignored.  The
               mapping pattern can be separated from the filename by
               whitespace or an equals (**=**) character.
    
               The options can be specified multiple times.  Their contents
               accumulate.  The remappings will be processed in the order in
               which they occur on the command line, and if they come from a
               file, in the order in which they occur in the file.  If a
               match is made, no further checking for that filename will be
               performed.
    
               If the replacement filename is _/dev/null_ or just _NUL_ then the
               remapping will actually cause the input file to be ignored.
               This can be a convenient way to experiment with removing input
               files from a complicated build environment.
    
               Note that this option is position dependent and only affects
               filenames that come after it on the command line.  Thus:
    
                         ld foo.o --remap-inputs=foo.o=bar.o
    
               Will have no effect, whereas:
    
                         ld --remap-inputs=foo.o=bar.o foo.o
    
               Will rename the input file _foo.o_ to _bar.o_.
    
               Note - these options also affect files referenced by _INPUT_
               statements in linker scripts.  But since linker scripts are
               processed after the entire command line is read, the position
               of the remap options on the command line is not significant.
    
               If the **verbose** option is enabled then any mappings that match
               will be reported, although again the **verbose** option needs to
               be enabled on the command line _before_ the remaped filenames
               appear.
    
               If the **-Map** or **--print-map** options are enabled then the
               remapping list will be included in the map output.
    
           **-M**
           **--print-map**
               Print a link map to the standard output.  A link map provides
               information about the link, including the following:
    
               •   Where object files are mapped into memory.
    
               •   How common symbols are allocated.
    
               •   All archive members included in the link, with a mention
                   of the symbol which caused the archive member to be
                   brought in.
    
               •   The values assigned to symbols.
    
                   Note - symbols whose values are computed by an expression
                   which involves a reference to a previous value of the same
                   symbol may not have correct result displayed in the link
                   map.  This is because the linker discards intermediate
                   results and only retains the final value of an expression.
                   Under such 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.
    
               •   How GNU properties are merged.
    
                   When the linker merges input .note.gnu.property sections
                   into one output .note.gnu.property section, some
                   properties are removed or updated.  These actions are
                   reported in the link map.  For example:
    
                           Removed property 0xc0000002 to merge foo.o (0x1) and bar.o (not found)
    
                   This indicates that property 0xc0000002 is removed from
                   output when merging properties in  _foo.o_ , whose property
                   0xc0000002 value is 0x1, and _bar.o_ , which doesn't have
                   property 0xc0000002.
    
                           Updated property 0xc0010001 (0x1) to merge foo.o (0x1) and bar.o (0x1)
    
                   This indicates that property 0xc0010001 value is updated
                   to 0x1 in output when merging properties in  _foo.o_ , whose
                   0xc0010001 property value is 0x1, and _bar.o_ , whose
                   0xc0010001 property value is 0x1.
    
               •   On some ELF targets, a list of fixups inserted by **--relax**
    
                           foo.o: Adjusting branch at 0x00000008 towards "far" in section .text
    
                   This indicates that the branch at 0x00000008 in foo.o,
                   targeting the symbol "far" in section .text, has been
                   replaced by a trampoline.
    
           **--print-map-discarded**
           **--no-print-map-discarded**
               Print (or do not print) the list of discarded and garbage
               collected sections in the link map.  Enabled by default.
    
           **--print-map-locals**
           **--no-print-map-locals**
               Print (or do not print) local symbols in the link map.  Local
               symbols will have the text **(local)** printed before their name,
               and will be listed after all of the global symbols in a given
               section.  Temporary local symbols (typically those that start
               with **.L**) will not be included in the output.  Disabled by
               default.
    
           **-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.
    
               Note - the linker will delete the output file before it starts
               to write to it.  It will do this even if it turns out that the
               link cannot be completed due to errors.
    
               Note - the linker will check to make sure that the output file
               name does not match the name of any of the input files, but
               that is all.  In particular it will not complain if the output
               file might overwrite a source file or some other important
               file.  Therefore in build systems it is recommended to use the
               **-o** option as the last option on the linker command line.  For
               example consider:
    
                         ld -o $(EXE) $(OBJS)
                         ld $(OBJS) -o $(EXE)
    
               If the **EXE** variable is not defined for some reason, the first
               version of the linker command could end up deleting one of the
               object files (the first one in the **OBJS** list) whereas the
               second version of the linker command will generate an error
               message and not delete anything.
    
           **--dependency-file=**_depfile_
               Write a _dependency file_ to _depfile_.  This file contains a rule
               suitable for "make" describing the output file and all the
               input files that were read to produce it.  The output is
               similar to the compiler's output with **-M -MP**.  Note that there
               is no option like the compiler's **-MM** , to exclude "system
               files" (which is not a well-specified concept in the linker,
               unlike "system headers" in the compiler).  So the output from
               **--dependency-file** is always specific to the exact state of the
               installation where it was produced, and should not be copied
               into distributed makefiles without careful editing.
    
           **-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.
    
           **-plugin** _name_
               Involve a plugin in the linking process.  The _name_ parameter
               is the absolute filename of the plugin.  Usually this
               parameter is automatically added by the complier, when using
               link time optimization, but users can also add their own
               plugins if they so wish.
    
               Note that the location of the compiler originated plugins is
               different from the place where the **ar** , **nm** and **ranlib** programs
               search for their plugins.  In order for those commands to make
               use of a compiler based plugin it must first be copied into
               the _${libdir}/bfd-plugins_ directory.  All gcc based linker
               plugins are backward compatible, so it is sufficient to just
               copy in the newest one.
    
           **--push-state**
               The **--push-state** allows one 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
    
           **--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.
    
               When the relocatable output contains both contents which
               require link-time optimization (LTO) and contents which don't
               require LTO, a .gnu_object_only section will be created to
               contain a relocatable object file, as if **-r** is applied to all
               relocatable inputs which don't require LTO.  When processing a
               relocatable input with a .gnu_object_only section, the linker
               will extract the .gnu_object_only section as a separate input.
    
               Note that since **-r** groups some sections from different input
               files together, there may be negative impacts on code size and
               locality in final executable or shared library.
    
               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.
    
           **--rosegment**
           **--no-rosegment**
               Attempt to ensure that only a single read-only, non-code
               segment is created.  Only useful when used in conjunction with
               the **-z separate-code** option.  The resulting binaries should be
               smaller than if **-z separate-code** is used on its own.  Without
               this option, or if **--no-rosegment** is specified, the **-z**
               **separate-code** option will create two read-only segments, one
               before the code segment and one after it.
    
               The name of the options are misleading, but they have been
               chosen in order for the linker to be compatible with the LLD
               and GOLD linkers.
    
               Thse options are only supported by ELF targets.
    
           **-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.
    
           **--strip-discarded**
           **--no-strip-discarded**
               Omit (or do not omit) global symbols defined in discarded
               sections.  Enabled by default.
    
           **-plugin-save-temps**
               Store the plugin "temporary" intermediate files permanently.
    
           **-t**
           **--trace**
               Print the names of the input files as **ld** processes them.  If
               **-t** is given twice then members within archives are also
               printed.  **-t** output is useful to generate a list of all the
               object files and scripts involved in linking, for example,
               when packaging files for a linker bug report.
    
           **-T** _scriptfile_
           **--script=**_scriptfile_
               Use _scriptfile_ as the linker script.  This script replaces
               **ld** 's default linker script (rather than adding to it), unless
               the script contains "INSERT", 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.
    
               Command line options that appear before the **-T** option can
               affect the script, but command line options that appear after
               it do not.
    
               Multiple **-T** options will accumulate if they are augmenting the
               current script, otherwise the last, non-augmenting, **-T** option
               will be used.
    
               There are other ways of specifying linker scripts.  See
    
           **-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 programs that do not use constructors or destructors, or
               for ELF based systems this option is equivalent to **-r** :  it
               generates relocatable output---i.e., an output file that can
               in turn serve as input to **ld**.  For other binaries however the
               **-Ur** option is similar to **-r** but it also resolves references to
               constructors and destructors.
    
               For those systems where **-r** and **-Ur** behave differently, 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 affects 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.  See also the description of the
               **--enable-linker-version** in **Options,,Command-line Options** which
               can be used to insert the linker version string into a binary.
    
           **-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:
    
               **call-nop=prefix-addr**
               **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=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.
    
               **cet-report=none**
               **cet-report=warning**
               **cet-report=error**
                   Specify how to report the missing
                   GNU_PROPERTY_X86_FEATURE_1_IBT and
                   GNU_PROPERTY_X86_FEATURE_1_SHSTK properties in input
                   .note.gnu.property section.  **cet-report=none** , which is the
                   default, will make the linker not report missing
                   properties in input files.  **cet-report=warning** will make
                   the linker issue a warning for missing properties in input
                   files.  **cet-report=error** will make the linker issue an
                   error for missing properties in input files.  Note that
                   **ibt** will turn off the missing
                   GNU_PROPERTY_X86_FEATURE_1_IBT property report and **shstk**
                   will turn off the missing GNU_PROPERTY_X86_FEATURE_1_SHSTK
                   property report.  Supported for Linux/i386 and
                   Linux/x86_64.
    
               **combreloc**
               **nocombreloc**
                   Combine multiple dynamic relocation sections and sort to
                   improve dynamic symbol lookup caching.  Do not do this if
                   **nocombreloc**.
    
               **common**
               **nocommon**
                   Generate common symbols with STT_COMMON type during a
                   relocatable link.  Use STT_OBJECT type if **nocommon**.
    
               **common-page-size=**_value_
                   Set the page size most commonly used to _value_.  Memory
                   image layout will be optimized to minimize memory pages if
                   the system is using pages of this size.
    
               **defs**
                   Report unresolved symbol references from regular object
                   files.  This is done even if the linker is creating a
                   non-symbolic shared library.  This option is the inverse
                   of **-z undefs**.
    
               **dynamic-undefined-weak**
               **nodynamic-undefined-weak**
                   Make undefined weak symbols dynamic when building a
                   dynamic object, if they are referenced from a regular
                   object file and not forced local by symbol visibility or
                   versioning.  Do not make them dynamic if
                   **nodynamic-undefined-weak**.  If neither option is given, a
                   target may default to either option being in force, or
                   make some other selection of undefined weak symbols
                   dynamic.  Not all targets support these options.
    
               **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.
    
               **ibtplt**
                   Generate Intel Indirect Branch Tracking (IBT) enabled PLT
                   entries.  Supported for Linux/i386 and Linux/x86_64.
    
               **ibt** Generate GNU_PROPERTY_X86_FEATURE_1_IBT in
                   .note.gnu.property section to indicate compatibility with
                   IBT.  This also implies **ibtplt**.  Supported for Linux/i386
                   and Linux/x86_64.
    
               **indirect-extern-access**
               **noindirect-extern-access**
                   Generate GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS in
                   .note.gnu.property section to indicate that object file
                   requires canonical function pointers and cannot be used
                   with copy relocation.  This option also implies
                   **noextern-protected-data** and **nocopyreloc**.  Supported for
                   i386 and x86-64.
    
                   **noindirect-extern-access** removes
                   GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS from
                   .note.gnu.property section.
    
               **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**
                   Specify that the dynamic loader should modify its symbol
                   search order so that symbols in this shared library
                   interpose all other shared libraries not so marked.
    
               **unique**
               **nounique**
                   When generating a shared library or other dynamically
                   loadable ELF object mark it as one that should (by
                   default) only ever be loaded once, and only in the main
                   namespace (when using "dlmopen"). This is primarily used
                   to mark fundamental libraries such as libc, libpthread et
                   al which do not usually function correctly unless they are
                   the sole instances of themselves. This behaviour can be
                   overridden by the "dlmopen" caller and does not apply to
                   certain loading mechanisms (such as audit libraries).
    
               **lam-u48**
                   Generate GNU_PROPERTY_X86_FEATURE_1_LAM_U48 in
                   .note.gnu.property section to indicate compatibility with
                   Intel LAM_U48.  Supported for Linux/x86_64.
    
               **lam-u57**
                   Generate GNU_PROPERTY_X86_FEATURE_1_LAM_U57 in
                   .note.gnu.property section to indicate compatibility with
                   Intel LAM_U57.  Supported for Linux/x86_64.
    
               **lam-u48-report=none**
               **lam-u48-report=warning**
               **lam-u48-report=error**
                   Specify how to report the missing
                   GNU_PROPERTY_X86_FEATURE_1_LAM_U48 property in input
                   .note.gnu.property section.  **lam-u48-report=none** , which is
                   the default, will make the linker not report missing
                   properties in input files.  **lam-u48-report=warning** will
                   make the linker issue a warning for missing properties in
                   input files.  **lam-u48-report=error** will make the linker
                   issue an error for missing properties in input files.
                   Supported for Linux/x86_64.
    
               **lam-u57-report=none**
               **lam-u57-report=warning**
               **lam-u57-report=error**
                   Specify how to report the missing
                   GNU_PROPERTY_X86_FEATURE_1_LAM_U57 property in input
                   .note.gnu.property section.  **lam-u57-report=none** , which is
                   the default, will make the linker not report missing
                   properties in input files.  **lam-u57-report=warning** will
                   make the linker issue a warning for missing properties in
                   input files.  **lam-u57-report=error** will make the linker
                   issue an error for missing properties in input files.
                   Supported for Linux/x86_64.
    
               **lam-report=none**
               **lam-report=warning**
               **lam-report=error**
                   Specify how to report the missing
                   GNU_PROPERTY_X86_FEATURE_1_LAM_U48 and
                   GNU_PROPERTY_X86_FEATURE_1_LAM_U57 properties in input
                   .note.gnu.property section.  **lam-report=none** , which is the
                   default, will make the linker not report missing
                   properties in input files.  **lam-report=warning** will make
                   the linker issue a warning for missing properties in input
                   files.  **lam-report=error** will make the linker issue an
                   error for missing properties in input files.  Supported
                   for Linux/x86_64.
    
               **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**
                   Specify that the object's filters be processed immediately
                   at runtime.
    
               **max-page-size=**_value_
                   Set the maximum memory page size supported to _value_.
    
               **mark-plt**
               **nomark-plt**
                   Mark PLT entries with dynamic tags, DT_X86_64_PLT,
                   DT_X86_64_PLTSZ and DT_X86_64_PLTENT.  Since this option
                   stores a non-zero value in the r_addend field of
                   R_X86_64_JUMP_SLOT relocations, the resulting executables
                   and shared libraries are incompatible with dynamic
                   linkers, such as those in older versions of glibc without
                   the change to ignore r_addend in R_X86_64_GLOB_DAT and
                   R_X86_64_JUMP_SLOT relocations, which don't ignore the
                   r_addend field of R_X86_64_JUMP_SLOT relocations.
                   Supported for x86_64.
    
               **muldefs**
                   Allow multiple definitions.
    
               **nocopyreloc**
                   Disable linker generated .dynbss variables used in place
                   of variables defined in shared libraries.  May result in
                   dynamic text relocations.
    
               **nodefaultlib**
                   Specify that the dynamic loader search for dependencies of
                   this object should ignore any default library search
                   paths.
    
               **nodelete**
                   Specify that the object shouldn't be unloaded at runtime.
    
               **nodlopen**
                   Specify that the object is not available to "dlopen".
    
               **nodump**
                   Specify that the object can not be dumped by "dldump".
    
               **noexecstack**
                   Marks the object as not requiring executable stack.
    
               **noextern-protected-data**
                   Don't treat protected data symbols as external when
                   building a shared library.  This option overrides the
                   linker backend default.  It can be used to work around
                   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.
    
               **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.
    
               **memory-seal**
               **nomemory-seal**
                   Instruct the executable or shared library that the all
                   PT_LOAD segments should be sealed to avoid further
                   manipulation (such as changing the protection flags, the
                   segment size, or remove the mapping).  This is a security
                   hardening that requires system support.  This generates
                   GNU_PROPERTY_MEMORY_SEAL in .note.gnu.property section
    
               **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 loaded
                   by dlopen, instead of deferring function call resolution
                   to the point when the function is first called.
    
               **origin**
                   Specify that the object requires **$ORIGIN** handling in
                   paths.
    
               **pack-relative-relocs**
               **nopack-relative-relocs**
                   Generate compact relative relocation in
                   position-independent executable and shared library.  It
                   adds "DT_RELR", "DT_RELRSZ" and "DT_RELRENT" entries to
                   the dynamic section.  It is ignored when building
                   position-dependent executable and relocatable output.
                   **nopack-relative-relocs** is the default, which disables
                   compact relative relocation.  When linked against the GNU
                   C Library, a GLIBC_ABI_DT_RELR symbol version dependency
                   on the shared C Library is added to the output.  Supported
                   for i386 and x86-64.
    
               **relro**
               **norelro**
                   Create an ELF "PT_GNU_RELRO" segment header in the object.
                   This specifies a memory segment that should be made
                   read-only after relocation, if supported.  Specifying
                   **common-page-size** smaller than the system page size will
                   render this protection ineffective.  Don't create an ELF
                   "PT_GNU_RELRO" segment if **norelro**.
    
               **report-relative-reloc**
                   Report dynamic relative relocations generated by linker.
                   Supported for Linux/i386 and Linux/x86_64.
    
               **sectionheader**
               **nosectionheader**
                   Generate section header.  Don't generate section header if
                   **nosectionheader** is used.  **sectionheader** is the default.
    
               **separate-code**
               **noseparate-code**
                   Create separate code "PT_LOAD" segment header in the
                   object.  This specifies a memory segment that should
                   contain only instructions and must be in wholly disjoint
                   pages from any other data.  Don't create separate code
                   "PT_LOAD" segment if **noseparate-code** is used.
    
               **shstk**
                   Generate GNU_PROPERTY_X86_FEATURE_1_SHSTK in
                   .note.gnu.property section to indicate compatibility with
                   Intel Shadow Stack.  Supported for Linux/i386 and
                   Linux/x86_64.
    
               **stack-size=**_value_
                   Specify a stack size for an ELF "PT_GNU_STACK" segment.
                   Specifying zero will override any default non-zero sized
                   "PT_GNU_STACK" segment creation.
    
               **start-stop-gc**
               **nostart-stop-gc**
                   When **--gc-sections** is in effect, a reference from a
                   retained section to "__start_SECNAME" or "__stop_SECNAME"
                   causes all input sections named "SECNAME" to also be
                   retained, if "SECNAME" is representable as a C identifier
                   and either "__start_SECNAME" or "__stop_SECNAME" is
                   synthesized by the linker.  **-z start-stop-gc** disables this
                   effect, allowing sections to be garbage collected as if
                   the special synthesized symbols were not defined.  **-z**
                   **start-stop-gc** has no effect on a definition of
                   "__start_SECNAME" or "__stop_SECNAME" in an object file or
                   linker script.  Such a definition will prevent the linker
                   providing a synthesized "__start_SECNAME" or
                   "__stop_SECNAME" respectively, and therefore the special
                   treatment by garbage collection for those references.
    
               **start-stop-visibility=**_value_
                   Specify the ELF symbol visibility for synthesized
                   "__start_SECNAME" and "__stop_SECNAME" symbols.  _value_
                   must be exactly **default** , **internal** , **hidden** , or **protected**.
                   If no **-z start-stop-visibility** option is given, **protected**
                   is used for compatibility with historical practice.
                   However, it's highly recommended to use **-z**
                   **start-stop-visibility=hidden** in new programs and shared
                   libraries so that these symbols are not exported between
                   shared objects, which is not usually what's intended.
    
               **text**
               **notext**
               **textoff**
                   Report an error if DT_TEXTREL is set, i.e., if the
                   position-independent or shared object has dynamic
                   relocations in read-only sections.  Don't report an error
                   if **notext** or **textoff**.
    
               **undefs**
                   Do not report unresolved symbol references from regular
                   object files, either when creating an executable, or when
                   creating a shared library.  This option is the inverse of
                   **-z defs**.
    
               **unique-symbol**
               **nounique-symbol**
                   Avoid duplicated local symbol names in the symbol string
                   table.  Append "."number"" to duplicated local symbol
                   names if **unique-symbol** is used.  **nounique-symbol** is the
                   default.
    
               **x86-64-baseline**
               **x86-64-v2**
               **x86-64-v3**
               **x86-64-v4**
                   Specify the x86-64 ISA level needed in .note.gnu.property
                   section.  **x86-64-baseline** generates
                   "GNU_PROPERTY_X86_ISA_1_BASELINE".  **x86-64-v2** generates
                   "GNU_PROPERTY_X86_ISA_1_V2".  **x86-64-v3** generates
                   "GNU_PROPERTY_X86_ISA_1_V3".  **x86-64-v4** generates
                   "GNU_PROPERTY_X86_ISA_1_V4".  Supported for Linux/i386 and
                   Linux/x86_64.
    
               **isa-level-report=none**
               **isa-level-report=all**
               **isa-level-report=needed**
               **isa-level-report=used**
                   Specify how to report x86-64 ISA levels in input
                   relocatable files.  **isa-level-report=none** , which is the
                   default, will make the linker not report x86-64 ISA levels
                   in input files.  **isa-level-report=all** will make the linker
                   report needed and used x86-64 ISA levels in input files.
                   **isa-level-report=needed** will make the linker report needed
                   x86-64 ISA levels in input files.  **isa-level-report=used**
                   will make the linker report used x86-64 ISA levels in
                   input files.  Supported for Linux/i386 and Linux/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 will 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.
    
               Note: On Linux based systems the **--as-needed** option also has
               an affect on the behaviour of the **--rpath** and **--rpath-link**
               options.  See the description of **--rpath-link** for more
               details.
    
           **--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 is only meaningful on ELF platforms which support
               shared libraries.
    
           **-Bsymbolic-functions**
               When creating a shared library, bind references to global
               function symbols to the definition within the shared library,
               if any.  This option is only meaningful on ELF platforms which
               support shared libraries.
    
           **-Bno-symbolic**
               This option can cancel previously specified **-Bsymbolic** and
               **-Bsymbolic-functions**.
    
           **--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.
    
           **--ctf-variables**
           **--no-ctf-variables**
               The CTF debuginfo format supports a section which encodes the
               names and types of variables found in the program which do not
               appear in any symbol table. These variables clearly cannot be
               looked up by address by conventional debuggers, so the space
               used for their types and names is usually wasted: the types
               are usually small but the names are often not.
               **--ctf-variables** causes the generation of such a section.  The
               default behaviour can be restored with **--no-ctf-variables**.
    
           **--ctf-share-types=**_method_
               Adjust the method used to share types between translation
               units in CTF.
    
               **share-unconflicted**
                   Put all types that do not have ambiguous definitions into
                   the shared dictionary, where debuggers can easily access
                   them, even if they only occur in one translation unit.
                   This is the default.
    
               **share-duplicated**
                   Put only types that occur in multiple translation units
                   into the shared dictionary: types with only one definition
                   go into per-translation-unit dictionaries.  Types with
                   ambiguous definitions in multiple translation units always
                   go into per-translation-unit dictionaries.  This tends to
                   make the CTF larger, but may reduce the amount of CTF in
                   the shared dictionary.  For very large projects this may
                   speed up opening the CTF and save memory in the CTF
                   consumer at runtime.
    
           **--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.
    
           **--force-group-allocation**
               This option causes the linker to place section group members
               like normal input sections, and to delete the section groups.
               This is the default behaviour for a final link but this option
               can be used to change the behaviour of a relocatable link
               (**-r**).  The script command "FORCE_GROUP_ALLOCATION" has the
               same effect.
    
           **--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_.
    
               The linker processes **--defsym** arguments and **-T** arguments in
               order, placing **--defsym** before **-T** will define the symbol
               before the linker script from **-T** is processed, while placing
               **--defsym** after **-T** will define the symbol after the linker
               script has been processed.  This difference has consequences
               for expressions within the linker script that use the **--defsym**
               symbols, which order is correct will depend on what you are
               trying to achieve.
    
           **--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.
    
           **-I** _file_
           **--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.
    
           **--embedded-relocs**
               This option is similar to the **--emit-relocs** option except that
               the relocs are stored in a target-specific section.  This
               option is only supported by the **BFIN** , **CR16** and _M68K_ targets.
    
           **--disable-multiple-abs-defs**
               Do not allow multiple definitions with symbols included in
               filename invoked by -R or --just-symbols
    
           **--fatal-warnings**
           **--no-fatal-warnings**
               Treat all warnings as errors.  The default behaviour can be
               restored with the option **--no-fatal-warnings**.
    
           **-w**
           **--no-warnings**
               Do not display any warning or error messages.  This overrides
               **--fatal-warnings** if it has been enabled.  This option can be
               used when it is known that the output binary will not work,
               but there is still a need to create it.
    
           **--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** , **--undefined** , and **--gc-keep-exported**.
    
               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 one of the options **--entry** ,
               **--undefined** , or **--gc-keep-exported** or by a "ENTRY" command in
               the linker script.
    
               As a GNU extension, ELF input sections marked with the
               "SHF_GNU_RETAIN" flag will not be garbage collected.
    
           **--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.
    
           **--gc-keep-exported**
               When **--gc-sections** is enabled, this option prevents garbage
               collection of unused input sections that contain global
               symbols having default or protected visibility.  This option
               is intended to be used for executables where unreferenced
               sections would otherwise be garbage collected regardless of
               the external visibility of contained symbols.  Note that this
               option has no effect when linking shared objects since it is
               already the default behaviour.  This option is only supported
               for ELF format targets.
    
           **--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.  If _mapfile_ is just the character "-"
               then the map will be written to stdout.
    
               Specifying a directory as _mapfile_ causes the linker map to be
               written as a file inside the directory.  Normally name of the
               file inside the directory is computed as the basename of the
               _output_ file with ".map" appended.   If however the special
               character "%" is used then this will be replaced by the full
               path of the output file.  Additionally if there are any
               characters after the _%_ symbol then ".map" will no longer be
               appended.
    
                        -o foo.exe -Map=bar                  [Creates ./bar]
                        -o ../dir/foo.exe -Map=bar           [Creates ./bar]
                        -o foo.exe -Map=../dir               [Creates ../dir/foo.exe.map]
                        -o ../dir2/foo.exe -Map=../dir       [Creates ../dir/foo.exe.map]
                        -o foo.exe -Map=%                    [Creates ./foo.exe.map]
                        -o ../dir/foo.exe -Map=%             [Creates ../dir/foo.exe.map]
                        -o foo.exe -Map=%.bar                [Creates ./foo.exe.bar]
                        -o ../dir/foo.exe -Map=%.bar         [Creates ../dir/foo.exe.bar]
                        -o ../dir2/foo.exe -Map=../dir/%     [Creates ../dir/../dir2/foo.exe.map]
                        -o ../dir2/foo.exe -Map=../dir/%.bar [Creates ../dir/../dir2/foo.exe.bar]
    
               It is an error to specify more than one "%" character.
    
               If the map file already exists then it will be overwritten by
               this operation.
    
           **--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.
    
               The effects of this option can be reverted by using "-z
               undefs".
    
           **--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:
    
               •   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.
    
               •   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.
    
           **--error-handling-script=**_scriptname_
               If this option is provided then the linker will invoke
               _scriptname_ whenever an error is encountered.  Currently
               however only two kinds of error are supported: missing symbols
               and missing libraries.  Two arguments will be passed to
               script: the keyword "undefined-symbol" or `missing-lib" and
               the _name_ of the undefined symbol or missing library.  The
               intention is that the script will provide suggestions to the
               user as to where the symbol or library might be found.  After
               the script has finished then the normal linker error message
               will be displayed.
    
               The availability of this option is controlled by a configure
               time switch, so it may not be present in specific
               implementations.
    
           **--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.
    
           **--out-implib** _file_
               Create an import library in _file_ corresponding to the
               executable the linker is generating (eg. a DLL or ELF
               program).  This import library (which should be called
               "*.dll.a" or "*.a" for DLLs) may be used to link clients
               against the generated executable; this behaviour makes it
               possible to skip a separate import library creation step (eg.
               "dlltool" for DLLs).  This option is only available for the
               i386 PE and ELF targetted ports of the linker.
    
           **-pie**
           **--pic-executable**
               Create a position independent executable.  This is currently
               only supported on ELF platforms.  Position independent
               executables are relocated by the dynamic linker to the virtual
               address the OS chooses for them, which can vary between
               invocations.  They are marked ET_DYN in the ELF file header,
               but differ from shared libraries in a number of ways.  In
               particular, defined symbols in a PIE by default can not be
               overridden by another object as they can be in a shared
               library.
    
           **-no-pie**
               Create a position dependent executable.  This is the default.
    
           **-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 the feature is supported, the option
               **--no-relax** will disable it.
    
               On platforms where the feature is not supported, both **--relax**
               and **--no-relax** are accepted, but ignored.
    
           **--retain-symbols-file=**_filename_
               Retain _only_ the symbols listed in the file _filename_ ,
               discarding all others.  _filename_ is simply a flat file, with
               one symbol name per line.  This option is especially useful in
               environments (such as VxWorks) where a large global symbol
               table is accumulated gradually, to conserve run-time memory.
    
               **--retain-symbols-file** does _not_ discard undefined symbols, or
               symbols needed for relocations.
    
               You may only specify **--retain-symbols-file** once in the command
               line.  It overrides **-s** and **-S**.
    
           **-rpath=**_dir_
               Add a directory to the runtime library search path.  This is
               used when linking an ELF executable with shared objects.  All
               **-rpath** arguments are concatenated and passed to the runtime
               linker, which uses them to locate shared objects at runtime.
    
               The **-rpath** option is also used when locating shared objects
               which are needed by shared objects explicitly included in the
               link; see the description of the **-rpath-link** option.
               Searching **-rpath** in this way is only supported by native
               linkers and cross linkers which have been configured with the
               **--with-sysroot** 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, several
               directories are searched as described below.  The **-rpath-link**
               option specifies the first set of directories to search.  This
               option may specify a sequence of directory names either by
               providing a list of names separated by colons, or by appearing
               multiple times.
    
               The tokens _$ORIGIN_ and _$LIB_ can appear in these search
               directories.  They will be replaced by the full path to the
               directory containing the program or shared object in the case
               of _$ORIGIN_ and either **lib** - for 32-bit binaries - or **lib64** -
               for 64-bit binaries - in the case of _$LIB_.
    
               The alternative form of these tokens - _${ORIGIN}_ and _${LIB}_
               can also be used.  The token _$PLATFORM_ is not supported.
    
               The **--rpath-link** 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
               unintentionally use a different search path than the runtime
               linker would have used.
    
               When additional shared libraries are required, the linker will
               search directories in the order listed below in order to find
               them.  Note however that this only applies to additional
               libraries needed to satisfy already included shared libraries.
               It does _not_ apply to libraries that are included via the **-l**
               command line option.  Searches for **-l** libraries are only
               conducted in directories specified by the **-L** option.
    
               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.  For a linker for a Linux system, if the file
                   _/etc/ld.so.conf_ exists, the list of directories found in
                   that file.  Note: the path to this file is prefixed with
                   the "sysroot" value, if that is defined, and then any
                   "prefix" string if the linker was configured with the
                   **--prefix= <path> **option.
    
               8.  For a native linker on a FreeBSD system, any directories
                   specified by the "_PATH_ELF_HINTS" macro defined in the
                   _elf-hints.h_ header file.
    
               9.  Any directories specified by a "SEARCH_DIR" command in a
                   linker script given on the command line, including scripts
                   specified by **-T**(but not **-dT**).
    
               10. The default directories, normally _/lib_ and _/usr/lib_.
    
               11. Any directories specified by a plugin
                   LDPT_SET_EXTRA_LIBRARY_PATH.
    
               12. Any directories specified by a "SEARCH_DIR" command in a
                   default linker script.
    
               Note however on Linux based systems there is an additional
               caveat:  If the **--as-needed** option is active _and_ a shared
               library is located which would normally satisfy the search _and_
               this library does not have DT_NEEDED tag for _libc.so and_ there
               is a shared library later on in the set of search directories
               which also satisfies the search _and_ this second shared library
               does have a DT_NEEDED tag for _libc.so then_ the second library
               will be selected instead of the first.
    
               If the required shared library is not found, the linker will
               issue a warning and continue with the link.
    
           **--section-ordering-file=**_script_
               This option is used to augment the current linker script with
               additional mapping of input sections to output sections.  This
               file must use the same syntax for "SECTIONS" as is used in
               normal linker scripts, but it should not do anything other
               than place input sections into output sections.
               @pxref{SECTIONS}
    
               A second constraint on the section ordering script is that it
               can only reference output sections that are already defined by
               whichever linker script is currently in use.  (Ie the default
               linker script or a script specified on the command line).  The
               benefit of the section ordering script however is that the
               input sections are mapped to the start of the output sections,
               so that they can ensure the ordering of sections in the output
               section.  For example, imagine that the default linker script
               looks like this:
    
                       SECTIONS {
                         .text : { *(.text.hot) ; *(.text .text.*) }
                         .data : { *(.data.big) ; *(.data .data.*) }
                         }
    
               Then if a section ordering file like this is used:
    
                         .text : { *(.text.first) ; *(.text.z*) }
                         .data : { foo.o(.data.first) ; *(.data.small) }
    
               This would be equivalent to a linker script like this:
    
                       SECTIONS {
                         .text : { *(.text.first) ; *(.text.z*) ; *(.text.hot) ; *(.text .text.*) }
                         .data : { foo.o(.data.first) ; *(.data.small) ; *(.data.big) ; *(.data .data.*) }
                         }
    
               The advantage of the section ordering file is that it can be
               used to order those sections that matter to the user without
               having to worry about any other sections, or memory regions,
               or anything else.
    
           **-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.
    
           **--spare-dynamic-tags=**_count_
               This option specifies the number of empty slots to leave in
               the .dynamic section of ELF shared objects.  Empty slots may
               be needed by post processing tools, such as the prelinker.
               The default is 5.
    
           **--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**.
    
           **--task-link**
               This is used by COFF/PE based targets to create a task-linked
               object file where all of the global symbols have been
               converted to statics.
    
           **--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_.
    
           **--image-base=**_org_
               When using ELF, same as **-Ttext-segment** , with both options
               effectively setting the base address of the ELF executable.
    
               When using PE, 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.
    
           **-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 first segment.  Note that when **-pie** is
               used with **-Ttext-segment=**_org_ , the output executable is marked
               ET_EXEC so that the address of the first byte of the text
               segment will be guaranteed to be _org_ at run time.
    
           **-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-execstack**
           **--warn-execstack-objects**
           **--no-warn-execstack**
               On ELF platforms the linker may generate warning messages if
               it is asked to create an output file that contains an
               executable stack.  There are three possible states:
    
               1.  Do not generate any warnings.
    
               2.  Always generate warnings, even if the executable stack is
                   requested via the **-z execstack** command line option.
    
               3.  Only generate a warning if an object file requests an
                   executable stack, but not if the **-z execstack** option is
                   used.
    
               The default state depends upon how the linker was configured
               when it was built.  The **--no-warn-execstack** option always puts
               the linker into the no-warnings state.  The **--warn-execstack**
               option puts the linker into the warn-always state.  The
               **--warn-execstack-objects** option puts the linker into the
               warn-for-object-files-only state.
    
               Note: ELF format input files can specify that they need an
               executable stack by having a _.note.GNU-stack_ section with the
               executable bit set in its section flags.  They can specify
               that they do not need an executable stack by having the same
               section, but without the executable flag bit set.  If an input
               file does not have a _.note.GNU-stack_ section then the default
               behaviour is target specific.  For some targets, then absence
               of such a section implies that an executable stack _is_
               required.  This is often a problem for hand crafted assembler
               files.
    
           **--error-execstack**
           **--no-error-execstack**
               If the linker is going to generate a warning message about an
               executable stack then the **--error-execstack** option will
               instead change that warning into an error.  Note - this option
               does not change the linker's execstack warning generation
               state.  Use **--warn-execstack** or **--warn-execstack-objects** to
               set a specific warning state.
    
               The **--no-error-execstack** option will restore the default
               behaviour of generating warning messages.
    
           **--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-rwx-segments**
           **--no-warn-rwx-segments**
               Warn if the linker creates a loadable, non-zero sized segment
               that has all three of the read, write and execute permission
               flags set.  Such a segment represents a potential security
               vulnerability.  In addition warnings will be generated if a
               thread local storage segment is created with the execute
               permission flag set, regardless of whether or not it has the
               read and/or write flags set.
    
               These warnings are enabled by default.  They can be disabled
               via the **--no-warn-rwx-segments** option and re-enabled via the
               **--warn-rwx-segments** option.
    
           **--error-rwx-segments**
           **--no-error-rwx-segments**
               If the linker is going to generate a warning message about an
               executable, writeable segment, or an executable TLS segment,
               then the **--error-rwx-segments** option will turn this warning
               into an error instead.  The **--no-error-rwx-segments** option
               will restore the default behaviour of just generating a
               warning message.
    
               Note - the **--error-rwx-segments** option does not by itself turn
               on warnings about these segments.  These warnings are either
               enabled by default, if the linker was configured that way, or
               via the **--warn-rwx-segments** command line option.
    
           **--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-textrel**
               Warn if the linker adds DT_TEXTREL to a position-independent
               executable or 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".
    
               Only undefined references are replaced by the linker.  So,
               translation unit internal references to _symbol_ are not
               resolved to "__wrap__symbol_ ".  In the next example, the call to
               "f" in "g" is not resolved to "__wrap_f".
    
                       int
                       f (void)
                       {
                         return 123;
                       }
    
                       int
                       g (void)
                       {
                         return f();
                       }
    
           **--eh-frame-hdr**
           **--no-eh-frame-hdr**
               Request (**--eh-frame-hdr**) or suppress (**--no-eh-frame-hdr**) the
               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.  This
               option also controls the generation of ".sframe" stack trace
               info for linker generated code sections like PLT.
    
           **--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 depends upon how the linker was configured, but for
               most Linux based systems it will be "both".
    
           **--compress-debug-sections=none**
           **--compress-debug-sections=zlib**
           **--compress-debug-sections=zlib-gnu**
           **--compress-debug-sections=zlib-gabi**
           **--compress-debug-sections=zstd**
               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 renames them to begin with **.zdebug** instead
               of **.debug**.  **--compress-debug-sections=zlib-gabi** also
               compresses DWARF debug sections, but rather than renaming them
               it sets the SHF_COMPRESSED flag in the sections' headers.
    
               The **--compress-debug-sections=zlib** option is an alias for
               **--compress-debug-sections=zlib-gabi**.
    
               **--compress-debug-sections=zstd** compresses DWARF debug sections
               using zstd.
    
               Note that this option overrides any compression in input debug
               sections, so if a binary is linked with
               **--compress-debug-sections=none** for example, then any
               compressed debug sections in input files will be uncompressed
               before they are copied into the output binary.
    
               The default compression behaviour varies depending upon the
               target involved and the configure options used to build the
               toolchain.  The default can be determined by examining 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.
    
           **--max-cache-size=**_size_
               **ld** normally caches the relocation information and symbol
               tables of input files in memory with the unlimited size.  This
               option sets the maximum cache size to _size_.
    
           **--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, "md5" to use a 128-bit MD5 hash, or "xx" to use a
               128-bit XXHASH on the normative parts of the output contents;
               or "0x _hexstring_ " 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", "sha1", and "xx" styles produces an identifier that
               is always the same in an identical output file, but are almost
               certainly 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.
    
           **--package-metadata=**_JSON_
               Request the creation of a ".note.package" ELF note section.
               The contents of the note are in JSON format, as per the
               package metadata specification.  For more information see:
               https://systemd.io/ELF_PACKAGE_METADATA/ The JSON argument
               support percent-encoding and following %[string] (where string
               refers to the name in HTML's Named Character References)
               encoding: **%[comma]** for **,** , **%[lbrace]** for **{** , **%[quot]** for **"** ,
               **%[rbrace]** for **}** , and **%[space]** for space character.  If the
               JSON argument is missing/empty then this will disable the
               creation of the metadata note, if one had been enabled by an
               earlier occurrence of the --package-metadata option.  If the
               linker has been built with libjansson, then the JSON string
               will be validated.
    
           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]
    
           **--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]
    
           **--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, thus making it possible to bypass the
               dllimport mechanism on the user side and to reference
               unmangled symbol names.  [This option is specific to the i386
               PE targeted port of the linker]
    
               The following remarks pertain to the original implementation
               of the feature and are obsolete nowadays for Cygwin and MinGW
               targets.
    
               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).
    
           **--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**
           **--disable-high-entropy-va**
               Image is compatible with 64-bit address space layout
               randomization (ASLR).  This option is enabled by default for
               64-bit PE images.
    
               This option also implies **--dynamicbase** and
               **--enable-reloc-section**.
    
           **--dynamicbase**
           **--disable-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.  This option is enabled
               by default but can be disabled via the **--disable-dynamicbase**
               option.  This option also implies **--enable-reloc-section**.
    
           **--forceinteg**
           **--disable-forceinteg**
               Code integrity checks are enforced.  This option is disabled
               by default.
    
           **--nxcompat**
           **--disable-nxcompat**
               The image is compatible with the Data Execution Prevention.
               This feature was introduced with MS Windows XP SP2 for i386 PE
               targets.  The option is enabled by default.
    
           **--no-isolation**
           **--disable-no-isolation**
               Although the image understands isolation, do not isolate the
               image.  This option is disabled by default.
    
           **--no-seh**
           **--disable-no-seh**
               The image does not use SEH. No SE handler may be called from
               this image.  This option is disabled by default.
    
           **--no-bind**
           **--disable-no-bind**
               Do not bind this image.  This option is disabled by default.
    
           **--wdmdriver**
           **--disable-wdmdriver**
               The driver uses the MS Windows Driver Model.  This option is
               disabled by default.
    
           **--tsaware**
           **--disable-tsaware**
               The image is Terminal Server aware.  This option is disabled
               by default.
    
           **--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.
    
               If **--insert-timestamp** is active then the time inserted is
               either the time that the linking takes place or, if the
               "SOURCE_DATE_EPOCH" environment variable is defined, the
               number of seconds since Unix epoch as specified by that
               variable.
    
           **--enable-reloc-section**
           **--disable-reloc-section**
               Create the base relocation table, which is necessary if the
               image is loaded at a different image base than specified in
               the PE header.  This option is enabled by default.
    
           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.
    
           **--branch-stub**
               This option enables linker branch relaxation by inserting
               branch stub sections when needed to extend the range of
               branches.  This option is usually not required since C-SKY
               supports branch and call instructions that can access the full
               memory range and branch relaxation is normally handled by the
               compiler or assembler.
    
           **--stub-group-size=**_N_
               This option allows finer control of linker branch stub
               creation.  It sets the maximum size of a group of input
               sections that can be handled by one stub section.  A negative
               value of _N_ locates stub sections after their branches, while a
               positive value allows stub sections to appear either before or
               after the branches.  Values of **1** or **-1** indicate that the
               linker should choose suitable defaults.
    
           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 and branch relocation checks for ISA mode
           transitions 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.
    
           **--ignore-branch-isa**
           **--no-ignore-branch-isa**
               These options control branch relocation checks for invalid ISA
               mode transitions.  If **--ignore-branch-isa** is used, then the
               linker accepts any branch relocations and any ISA mode
               transition required is lost in relocation calculation, except
               for some cases of "BAL" instructions which meet relaxation
               conditions and are converted to equivalent "JALX" instructions
               as the associated relocation is calculated.  By default or if
               **--no-ignore-branch-isa** is used a check is made causing the
               loss of an ISA mode transition to produce an error.
    
           **--compact-branches**
           **--no-compact-branches**
               These options control the generation of compact instructions
               by the linker in the PLT entries for MIPS R6.
    
           For the pdp11-aout target, three variants of the output format can
           be produced as selected by the following options.  The default
           variant for pdp11-aout is the **--omagic** option, whereas for other
           targets **--nmagic** is the default.  The **--imagic** option is defined
           only for the pdp11-aout target, while the others are described
           here as they apply to the pdp11-aout target.
    
           **-N**
           **--omagic**
               Mark the output as "OMAGIC" (0407) in the _a.out_ header to
               indicate that the text segment is not to be write-protected
               and shared.  Since the text and data sections are both
               readable and writable, the data section is allocated
               immediately contiguous after the text segment.  This is the
               oldest format for PDP11 executable programs and is the default
               for **ld** on PDP11 Unix systems from the beginning through
               2.11BSD.
    
           **-n**
           **--nmagic**
               Mark the output as "NMAGIC" (0410) in the _a.out_ header to
               indicate that when the output file is executed, the text
               portion will be read-only and shareable among all processes
               executing the same file.  This involves moving the data areas
               up to the first possible 8K byte page boundary following the
               end of the text.  This option creates a _pure executable_
               format.
    
           **-z**
           **--imagic**
               Mark the output as "IMAGIC" (0411) in the _a.out_ header to
               indicate that when the output file is executed, the program
               text and data areas will be loaded into separate address
               spaces using the split instruction and data space feature of
               the memory management unit in larger models of the PDP11.
               This doubles the address space available to the program.  The
               text segment is again pure, write-protected, and shareable.
               The only difference in the output format between this option
               and the others, besides the magic number, is that both the
               text and data sections start at location 0.  The **-z** option
               selected this format in 2.11BSD.  This option creates a
               _separate executable_ format.
    
           **--no-omagic**
               Equivalent to **--nmagic** for pdp11-aout.
    


## 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.
    
           If the PE/COFF specific **--insert-timestamp** is active and the
           **SOURCE_DATE_EPOCH** environment variable is defined, then the
           timestamp value in this variable will be inserted into the COFF
           header instead of the current time.
    


* * *