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LD(1)                     GNU Development Tools                    LD(1)

NAME         top

       ld - The GNU linker

SYNOPSIS         top

       ld [options] objfile ...

DESCRIPTION         top

       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         top

       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.

       --remap-inputs=pattern=filename
       --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.

       --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.

           This option does the same thing as -i.

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

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

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

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

       --strip-discarded
       --no-strip-discarded
           Omit (or do not omit) global symbols defined in discarded
           sections.  Enabled by default.

       -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.  Multiple -T options accumulate.

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

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

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

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

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

       -Ur For 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.

           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.

           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.

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

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

       --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 similar to shared libraries in that they are
           relocated by the dynamic linker to the virtual address the OS
           chooses for them (which can vary between invocations).  Like
           normal dynamically linked executables they can be executed
           and symbols defined in the executable cannot be overridden by
           shared libraries.

       -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, the
           -rpath-link option specifies the first set of directories to
           search.  The -rpath-link option may specify a sequence of
           directory names either by specifying a list of names
           separated by colons, or by appearing multiple times.

           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.

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

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

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

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

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

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

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

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

           7.  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.

       -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.

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

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

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

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

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

           ignore-all
               Do not report any unresolved symbols.

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

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

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

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

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

       --dll-verbose
       --verbose[=NUMBER]
           Display the version number for ld and list the linker
           emulations supported.  Display which input files can and
           cannot be opened.  Display the linker script being used by
           the linker. If the optional NUMBER argument > 1, plugin
           symbol status will also be displayed.

       --version-script=version-scriptfile
           Specify the name of a version script to the linker.  This is
           typically used when creating shared libraries to specify
           additional information about the version hierarchy for the
           library being created.  This option is only fully supported
           on ELF platforms which support shared libraries; see VERSION.
           It is partially supported on PE platforms, which can use
           version scripts to filter symbol visibility in auto-export
           mode: any symbols marked local in the version script will not
           be exported.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

       --warn-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 on the normative parts of the output contents,
           "md5" to use a 128-bit MD5 hash on the normative parts of the
           output contents, or "0xhexstring" to use a chosen bit string
           specified as an even number of hexadecimal digits ("-" and
           ":" characters between digit pairs are ignored).  If style is
           omitted, "sha1" is used.

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

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

       --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/ 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]

       --image-base value
           Use value as the base address of your program or dll.  This
           is the lowest memory location that will be used when your
           program or dll is loaded.  To reduce the need to relocate and
           improve performance of your dlls, each should have a unique
           base address and not overlap any other dlls.  The default is
           0x400000 for executables, and 0x10000000 for dlls.  [This
           option is specific to the i386 PE targeted port of the
           linker]

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

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

       --disable-large-address-aware
           Reverts the effect of a previous --large-address-aware
           option.  This is useful if --large-address-aware is always
           set by the compiler driver (e.g. Cygwin gcc) and the
           executable does not support virtual addresses greater than 2
           gigabytes.  [This option is specific to PE targeted ports of
           the linker]

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

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

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

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

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

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

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

       --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         top

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

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

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

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

SEE ALSO         top

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

COPYRIGHT         top

       Copyright (c) 1991-2024 Free Software Foundation, Inc.

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

COLOPHON         top

       This page is part of the binutils (a collection of tools for
       working with executable binaries) project.  Information about the
       project can be found at ⟨http://www.gnu.org/software/binutils/⟩.
       If you have a bug report for this manual page, see
       ⟨http://sourceware.org/bugzilla/enter_bug.cgi?product=binutils⟩.
       This page was obtained from the tarball binutils-2.42.tar.gz
       fetched from ⟨https://ftp.gnu.org/gnu/binutils/⟩ on 2024-06-14.
       If you discover any rendering problems in this HTML version of
       the page, or you believe there is a better or more up-to-date
       source for the page, or you have corrections or improvements to
       the information in this COLOPHON (which is not part of the
       original manual page), send a mail to [email protected]

binutils-2.42                  2024-01-29                          LD(1)

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