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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.
       -A architecture
       --architecture=architecture
           In the current release of ld, this option is useful only for the
           Intel 960 family of architectures.  In that ld configuration, the
           architecture argument identifies the particular architecture in
           the 960 family, enabling some safeguards and modifying the
           archive-library search path.
           Future releases of ld may support similar functionality for other
           architecture families.
       -b input-format
       --format=input-format
           ld may be configured to support more than one kind of object
           file.  If your ld is configured this way, you can use the -b
           option to specify the binary format for input object files that
           follow this option on the command line.  Even when ld is
           configured to support alternative object formats, you don't
           usually need to specify this, as ld should be configured to
           expect as a default input format the most usual format on each
           machine.  input-format is a text string, the name of a particular
           format supported by the BFD libraries.  (You can list the
           available binary formats with objdump -i.)
           You may want to use this option if you are linking files with an
           unusual binary format.  You can also use -b to switch formats
           explicitly (when linking object files of different formats), by
           including -b input-format before each group of object files in a
           particular format.
           The default format is taken from the environment variable
           "GNUTARGET".
           You can also define the input format from a script, using the
           command "TARGET";
       -c MRI-commandfile
       --mri-script=MRI-commandfile
           For compatibility with linkers produced by MRI, ld accepts script
           files written in an alternate, restricted command language,
           described in the MRI Compatible Script Files section of GNU ld
           documentation.  Introduce MRI script files with the option -c;
           use the -T option to run linker scripts written in the general-
           purpose ld scripting language.  If MRI-cmdfile does not exist, ld
           looks for it in the directories specified by any -L options.
       -d
       -dc
       -dp These three options are equivalent; multiple forms are supported
           for compatibility with other linkers.  They assign space to
           common symbols even if a relocatable output file is specified
           (with -r).  The script command "FORCE_COMMON_ALLOCATION" has the
           same effect.
       --depaudit AUDITLIB
       -P AUDITLIB
           Adds AUDITLIB to the "DT_DEPAUDIT" entry of the dynamic section.
           AUDITLIB is not checked for existence, nor will it use the
           DT_SONAME specified in the library.  If specified multiple times
           "DT_DEPAUDIT" will contain a colon separated list of audit
           interfaces to use.  This option is only meaningful on ELF
           platforms supporting the rtld-audit interface.  The -P option is
           provided for Solaris compatibility.
       -e entry
       --entry=entry
           Use entry as the explicit symbol for beginning execution of your
           program, rather than the default entry point.  If there is no
           symbol named entry, the linker will try to parse entry as a
           number, and use that as the entry address (the number will be
           interpreted in base 10; you may use a leading 0x for base 16, or
           a leading 0 for base 8).
       --exclude-libs lib,lib,...
           Specifies a list of archive libraries from which symbols should
           not be automatically exported.  The library names may be
           delimited by commas or colons.  Specifying "--exclude-libs ALL"
           excludes symbols in all archive libraries from automatic export.
           This option is available only for the i386 PE targeted port of
           the linker and for ELF targeted ports.  For i386 PE, symbols
           explicitly listed in a .def file are still exported, regardless
           of this option.  For ELF targeted ports, symbols affected by this
           option will be treated as hidden.
       --exclude-modules-for-implib module,module,...
           Specifies a list of object files or archive members, from which
           symbols should not be automatically exported, but which should be
           copied wholesale into the import library being generated during
           the link.  The module names may be delimited by commas or colons,
           and must match exactly the filenames used by ld to open the
           files; for archive members, this is simply the member name, but
           for object files the name listed must include and match precisely
           any path used to specify the input file on the linker's command-
           line.  This option is available only for the i386 PE targeted
           port of the linker.  Symbols explicitly listed in a .def file are
           still exported, regardless of this option.
       -E
       --export-dynamic
       --no-export-dynamic
           When creating a dynamically linked executable, using the -E
           option or the --export-dynamic option causes the linker to add
           all symbols to the dynamic symbol table.  The dynamic symbol
           table is the set of symbols which are visible from dynamic
           objects at run time.
           If you do not use either of these options (or use the
           --no-export-dynamic option to restore the default behavior), the
           dynamic symbol table will normally contain only those symbols
           which are referenced by some dynamic object mentioned in the
           link.
           If you use "dlopen" to load a dynamic object which needs to refer
           back to the symbols defined by the program, rather than some
           other dynamic object, then you will probably need to use this
           option when linking the program itself.
           You can also use the dynamic list to control what symbols should
           be added to the dynamic symbol table if the output format
           supports it.  See the description of --dynamic-list.
           Note that this option is specific to ELF targeted ports.  PE
           targets support a similar function to export all symbols from a
           DLL or EXE; see the description of --export-all-symbols below.
       -EB Link big-endian objects.  This affects the default output format.
       -EL Link little-endian objects.  This affects the default output
           format.
       -f name
       --auxiliary=name
           When creating an ELF shared object, set the internal DT_AUXILIARY
           field to the specified name.  This tells the dynamic linker that
           the symbol table of the shared object should be used as an
           auxiliary filter on the symbol table of the shared object name.
           If you later link a program against this filter object, then,
           when you run the program, the dynamic linker will see the
           DT_AUXILIARY field.  If the dynamic linker resolves any symbols
           from the filter object, it will first check whether there is a
           definition in the shared object name.  If there is one, it will
           be used instead of the definition in the filter object.  The
           shared object name need not exist.  Thus the shared object name
           may be used to provide an alternative implementation of certain
           functions, perhaps for debugging or for machine specific
           performance.
           This option may be specified more than once.  The DT_AUXILIARY
           entries will be created in the order in which they appear on the
           command line.
       -F name
       --filter=name
           When creating an ELF shared object, set the internal DT_FILTER
           field to the specified name.  This tells the dynamic linker that
           the symbol table of the shared object which is being created
           should be used as a filter on the symbol table of the shared
           object name.
           If you later link a program against this filter object, then,
           when you run the program, the dynamic linker will see the
           DT_FILTER field.  The dynamic linker will resolve symbols
           according to the symbol table of the filter object as usual, but
           it will actually link to the definitions found in the shared
           object name.  Thus the filter object can be used to select a
           subset of the symbols provided by the object name.
           Some older linkers used the -F option throughout a compilation
           toolchain for specifying object-file format for both input and
           output object files.  The GNU linker uses other mechanisms for
           this purpose: the -b, --format, --oformat options, the "TARGET"
           command in linker scripts, and the "GNUTARGET" environment
           variable.  The GNU linker will ignore the -F option when not
           creating an ELF shared object.
       -fini=name
           When creating an ELF executable or shared object, call NAME when
           the executable or shared object is unloaded, by setting DT_FINI
           to the address of the function.  By default, the linker uses
           "_fini" as the function to call.
       -g  Ignored.  Provided for compatibility with other tools.
       -G value
       --gpsize=value
           Set the maximum size of objects to be optimized using the GP
           register to size.  This is only meaningful for object file
           formats such as MIPS ELF that support putting large and small
           objects into different sections.  This is ignored for other
           object file formats.
       -h name
       -soname=name
           When creating an ELF shared object, set the internal DT_SONAME
           field to the specified name.  When an executable is linked with a
           shared object which has a DT_SONAME field, then when the
           executable is run the dynamic linker will attempt to load the
           shared object specified by the DT_SONAME field rather than the
           using the file name given to the linker.
       -i  Perform an incremental link (same as option -r).
       -init=name
           When creating an ELF executable or shared object, call NAME when
           the executable or shared object is loaded, by setting DT_INIT to
           the address of the function.  By default, the linker uses "_init"
           as the function to call.
       -l namespec
       --library=namespec
           Add the archive or object file specified by namespec to the list
           of files to link.  This option may be used any number of times.
           If namespec is of the form :filename, ld will search the library
           path for a file called filename, otherwise it will search the
           library path for a file called libnamespec.a.
           On systems which support shared libraries, ld may also search for
           files other than libnamespec.a.  Specifically, on ELF and SunOS
           systems, ld will search a directory for a library called
           libnamespec.so before searching for one called libnamespec.a.
           (By convention, a ".so" extension indicates a shared library.)
           Note that this behavior does not apply to :filename, which always
           specifies a file called filename.
           The linker will search an archive only once, at the location
           where it is specified on the command line.  If the archive
           defines a symbol which was undefined in some object which
           appeared before the archive on the command line, the linker will
           include the appropriate file(s) from the archive.  However, an
           undefined symbol in an object appearing later on the command line
           will not cause the linker to search the archive again.
           See the -( option for a way to force the linker to search
           archives multiple times.
           You may list the same archive multiple times on the command line.
           This type of archive searching is standard for Unix linkers.
           However, if you are using ld on AIX, note that it is different
           from the behaviour of the AIX linker.
       -L searchdir
       --library-path=searchdir
           Add path searchdir to the list of paths that ld will search for
           archive libraries and ld control scripts.  You may use this
           option any number of times.  The directories are searched in the
           order in which they are specified on the command line.
           Directories specified on the command line are searched before the
           default directories.  All -L options apply to all -l options,
           regardless of the order in which the options appear.  -L options
           do not affect how ld searches for a linker script unless -T
           option is specified.
           If searchdir begins with "=", then the "=" will be replaced by
           the sysroot prefix, controlled by the --sysroot option, or
           specified when the linker is configured.
           The default set of paths searched (without being specified with
           -L) depends on which emulation mode ld is using, and in some
           cases also on how it was configured.
           The paths can also be specified in a link script with the
           "SEARCH_DIR" command.  Directories specified this way are
           searched at the point in which the linker script appears in the
           command line.
       -m emulation
           Emulate the emulation linker.  You can list the available
           emulations with the --verbose or -V options.
           If the -m option is not used, the emulation is taken from the
           "LDEMULATION" environment variable, if that is defined.
           Otherwise, the default emulation depends upon how the linker was
           configured.
       -M
       --print-map
           Print a link map to the standard output.  A link map provides
           information about the link, including the following:
           ·   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.
       -n
       --nmagic
           Turn off page alignment of sections, and disable linking against
           shared libraries.  If the output format supports Unix style magic
           numbers, mark the output as "NMAGIC".
       -N
       --omagic
           Set the text and data sections to be readable and writable.
           Also, do not page-align the data segment, and disable linking
           against shared libraries.  If the output format supports Unix
           style magic numbers, mark the output as "OMAGIC". Note: Although
           a writable text section is allowed for PE-COFF targets, it does
           not conform to the format specification published by Microsoft.
       --no-omagic
           This option negates most of the effects of the -N option.  It
           sets the text section to be read-only, and forces the data
           segment to be page-aligned.  Note - this option does not enable
           linking against shared libraries.  Use -Bdynamic for this.
       -o output
       --output=output
           Use output as the name for the program produced by ld; if this
           option is not specified, the name a.out is used by default.  The
           script command "OUTPUT" can also specify the output file name.
       -O level
           If level is a numeric values greater than zero ld optimizes the
           output.  This might take significantly longer and therefore
           probably should only be enabled for the final binary.  At the
           moment this option only affects ELF shared library generation.
           Future releases of the linker may make more use of this option.
           Also currently there is no difference in the linker's behaviour
           for different non-zero values of this option.  Again this may
           change with future releases.
       --push-state
           The --push-state allows to preserve the current state of the
           flags which govern the input file handling so that they can all
           be restored with one corresponding --pop-state option.
           The option which are covered are: -Bdynamic, -Bstatic, -dn, -dy,
           -call_shared, -non_shared, -static, -N, -n, --whole-archive,
           --no-whole-archive, -r, -Ur, --copy-dt-needed-entries,
           --no-copy-dt-needed-entries, --as-needed, --no-as-needed, and -a.
           One target for this option are specifications for pkg-config.
           When used with the --libs option all possibly needed libraries
           are listed and then possibly linked with all the time.  It is
           better to return something as follows:
                   -Wl,--push-state,--as-needed -libone -libtwo -Wl,--pop-state
           Undoes the effect of --push-state, restores the previous values
           of the flags governing input file handling.
       -q
       --emit-relocs
           Leave relocation sections and contents in fully linked
           executables.  Post link analysis and optimization tools may need
           this information in order to perform correct modifications of
           executables.  This results in larger executables.
           This option is currently only supported on ELF platforms.
       --force-dynamic
           Force the output file to have dynamic sections.  This option is
           specific to VxWorks targets.
       -r
       --relocatable
           Generate relocatable output---i.e., generate an output file that
           can in turn serve as input to ld.  This is often called partial
           linking.  As a side effect, in environments that support standard
           Unix magic numbers, this option also sets the output file's magic
           number to "OMAGIC".  If this option is not specified, an absolute
           file is produced.  When linking C++ programs, this option will
           not resolve references to constructors; to do that, use -Ur.
           When an input file does not have the same format as the output
           file, partial linking is only supported if that input file does
           not contain any relocations.  Different output formats can have
           further restrictions; for example some "a.out"-based formats do
           not support partial linking with input files in other formats at
           all.
           This option does the same thing as -i.
       -R filename
       --just-symbols=filename
           Read symbol names and their addresses from filename, but do not
           relocate it or include it in the output.  This allows your output
           file to refer symbolically to absolute locations of memory
           defined in other programs.  You may use this option more than
           once.
           For compatibility with other ELF linkers, if the -R option is
           followed by a directory name, rather than a file name, it is
           treated as the -rpath option.
       -s
       --strip-all
           Omit all symbol information from the output file.
       -S
       --strip-debug
           Omit debugger symbol information (but not all symbols) from the
           output file.
       -t
       --trace
           Print the names of the input files as ld processes them.
       -T scriptfile
       --script=scriptfile
           Use scriptfile as the linker script.  This script replaces ld's
           default linker script (rather than adding to it), so commandfile
           must specify everything necessary to describe the output file.
           If scriptfile does not exist in the current directory, "ld" looks
           for it in the directories specified by any preceding -L options.
           Multiple -T options accumulate.
       -dT scriptfile
       --default-script=scriptfile
           Use scriptfile as the default linker script.
           This option is similar to the --script option except that
           processing of the script is delayed until after the rest of the
           command line has been processed.  This allows options placed
           after the --default-script option on the command line to affect
           the behaviour of the linker script, which can be important when
           the linker command line cannot be directly controlled by the
           user.  (eg because the command line is being constructed by
           another tool, such as gcc).
       -u symbol
       --undefined=symbol
           Force symbol to be entered in the output file as an undefined
           symbol.  Doing this may, for example, trigger linking of
           additional modules from standard libraries.  -u may be repeated
           with different option arguments to enter additional undefined
           symbols.  This option is equivalent to the "EXTERN" linker script
           command.
           If this option is being used to force additional modules to be
           pulled into the link, and if it is an error for the symbol to
           remain undefined, then the option --require-defined should be
           used instead.
       --require-defined=symbol
           Require that symbol is defined in the output file.  This option
           is the same as option --undefined except that if symbol is not
           defined in the output file then the linker will issue an error
           and exit.  The same effect can be achieved in a linker script by
           using "EXTERN", "ASSERT" and "DEFINED" together.  This option can
           be used multiple times to require additional symbols.
       -Ur For anything other than C++ programs, this option is equivalent
           to -r: it generates relocatable output---i.e., an output file
           that can in turn serve as input to ld.  When linking C++
           programs, -Ur does resolve references to constructors, unlike -r.
           It does not work to use -Ur on files that were themselves linked
           with -Ur; once the constructor table has been built, it cannot be
           added to.  Use -Ur only for the last partial link, and -r for the
           others.
       --orphan-handling=MODE
           Control how orphan sections are handled.  An orphan section is
           one not specifically mentioned in a linker script.
           MODE can have any of the following values:
           "place"
               Orphan sections are placed into a suitable output section
               following the strategy described in Orphan Sections.  The
               option --unique also effects how sections are placed.
           "discard"
               All orphan sections are discarded, by placing them in the
               /DISCARD/ section.
           "warn"
               The linker will place the orphan section as for "place" and
               also issue a warning.
           "error"
               The linker will exit with an error if any orphan section is
               found.
           The default if --orphan-handling is not given is "place".
       --unique[=SECTION]
           Creates a separate output section for every input section
           matching SECTION, or if the optional wildcard SECTION argument is
           missing, for every orphan input section.  An orphan section is
           one not specifically mentioned in a linker script.  You may use
           this option multiple times on the command line;  It prevents the
           normal merging of input sections with the same name, overriding
           output section assignments in a linker script.
       -v
       --version
       -V  Display the version number for ld.  The -V option also lists the
           supported emulations.
       -x
       --discard-all
           Delete all local symbols.
       -X
       --discard-locals
           Delete all temporary local symbols.  (These symbols start with
           system-specific local label prefixes, typically .L for ELF
           systems or L for traditional a.out systems.)
       -y symbol
       --trace-symbol=symbol
           Print the name of each linked file in which symbol appears.  This
           option may be given any number of times.  On many systems it is
           necessary to prepend an underscore.
           This option is useful when you have an undefined symbol in your
           link but don't know where the reference is coming from.
       -Y path
           Add path to the default library search path.  This option exists
           for Solaris compatibility.
       -z keyword
           The recognized keywords are:
           combreloc
               Combines multiple reloc sections and sorts them to make
               dynamic symbol lookup caching possible.
           common
               Generate common symbols with the STT_COMMON type druing a
               relocatable link.
           defs
               Disallows undefined symbols in object files.  Undefined
               symbols in shared libraries are still allowed.
           execstack
               Marks the object as requiring executable stack.
           global
               This option is only meaningful when building a shared object.
               It makes the symbols defined by this shared object available
               for symbol resolution of subsequently loaded libraries.
           initfirst
               This option is only meaningful when building a shared object.
               It marks the object so that its runtime initialization will
               occur before the runtime initialization of any other objects
               brought into the process at the same time.  Similarly the
               runtime finalization of the object will occur after the
               runtime finalization of any other objects.
           interpose
               Marks the object that its symbol table interposes before all
               symbols but the primary executable.
           lazy
               When generating an executable or shared library, mark it to
               tell the dynamic linker to defer function call resolution to
               the point when the function is called (lazy binding), rather
               than at load time.  Lazy binding is the default.
           loadfltr
               Marks  the object that its filters be processed immediately
               at runtime.
           muldefs
               Allows multiple definitions.
           nocombreloc
               Disables multiple reloc sections combining.
           nocommon
               Generate common symbols with the STT_OBJECT type druing a
               relocatable link.
           nocopyreloc
               Disable linker generated .dynbss variables used in place of
               variables defined in shared libraries.  May result in dynamic
               text relocations.
           nodefaultlib
               Marks the object that the search for dependencies of this
               object will ignore any default library search paths.
           nodelete
               Marks the object shouldn't be unloaded at runtime.
           nodlopen
               Marks the object not available to "dlopen".
           nodump
               Marks the object can not be dumped by "dldump".
           noexecstack
               Marks the object as not requiring executable stack.
           text
               Treat DT_TEXTREL in shared object as error.
           notext
               Don't treat DT_TEXTREL in shared object as error.
           textoff
               Don't treat DT_TEXTREL in shared object as error.
           norelro
               Don't create an ELF "PT_GNU_RELRO" segment header in the
               object.
           now When generating an executable or shared library, mark it to
               tell the dynamic linker to resolve all symbols when the
               program is started, or when the shared library is linked to
               using dlopen, instead of deferring function call resolution
               to the point when the function is first called.
           origin
               Marks the object may contain $ORIGIN.
           relro
               Create an ELF "PT_GNU_RELRO" segment header in the object.
           max-page-size=value
               Set the emulation maximum page size to value.
           common-page-size=value
               Set the emulation common page size to value.
           stack-size=value
               Specify a stack size for in an ELF "PT_GNU_STACK" segment.
               Specifying zero will override any default non-zero sized
               "PT_GNU_STACK" segment creation.
           bndplt
               Always generate BND prefix in PLT entries. Supported for
               Linux/x86_64.
           noextern-protected-data
               Don't treat protected data symbol as external when building
               shared library.  This option overrides linker backend
               default.  It can be used to workaround incorrect relocations
               against protected data symbols generated by compiler.
               Updates on protected data symbols by another module aren't
               visible to the resulting shared library.  Supported for i386
               and x86-64.
           nodynamic-undefined-weak
               Don't treat undefined weak symbols as dynamic when building
               executable.  This option overrides linker backend default.
               It can be used to avoid dynamic relocations against undefined
               weak symbols in executable.  Supported for i386 and x86-64.
           noreloc-overflow
               Disable relocation overflow check.  This can be used to
               disable relocation overflow check if there will be no dynamic
               relocation overflow at run-time.  Supported for x86_64.
           call-nop=prefix-addr
           call-nop=prefix-nop
           call-nop=suffix-nop
           call-nop=prefix-byte
           call-nop=suffix-byte
               Specify the 1-byte "NOP" padding when transforming indirect
               call to a locally defined function, foo, via its GOT slot.
               call-nop=prefix-addr generates "0x67 call foo".
               call-nop=prefix-nop generates "0x90 call foo".
               call-nop=suffix-nop generates "call foo 0x90".
               call-nop=prefix-byte generates "byte call foo".
               call-nop=suffix-byte generates "call foo byte".  Supported
               for i386 and x86_64.
           Other keywords are ignored for Solaris compatibility.
       -( archives -)
       --start-group archives --end-group
           The archives should be a list of archive files.  They may be
           either explicit file names, or -l options.
           The specified archives are searched repeatedly until no new
           undefined references are created.  Normally, an archive is
           searched only once in the order that it is specified on the
           command line.  If a symbol in that archive is needed to resolve
           an undefined symbol referred to by an object in an archive that
           appears later on the command line, the linker would not be able
           to resolve that reference.  By grouping the archives, they all be
           searched repeatedly until all possible references are resolved.
           Using this option has a significant performance cost.  It is best
           to use it only when there are unavoidable circular references
           between two or more archives.
       --accept-unknown-input-arch
       --no-accept-unknown-input-arch
           Tells the linker to accept input files whose architecture cannot
           be recognised.  The assumption is that the user knows what they
           are doing and deliberately wants to link in these unknown input
           files.  This was the default behaviour of the linker, before
           release 2.14.  The default behaviour from release 2.14 onwards is
           to reject such input files, and so the
           --accept-unknown-input-arch option has been added to restore the
           old behaviour.
       --as-needed
       --no-as-needed
           This option affects ELF DT_NEEDED tags for dynamic libraries
           mentioned on the command line after the --as-needed option.
           Normally the linker will add a DT_NEEDED tag for each dynamic
           library mentioned on the command line, regardless of whether the
           library is actually needed or not.  --as-needed causes a
           DT_NEEDED tag to only be emitted for a library that at that point
           in the link satisfies a non-weak undefined symbol reference from
           a regular object file or, if the library is not found in the
           DT_NEEDED lists of other needed libraries, a non-weak undefined
           symbol reference from another needed dynamic library.  Object
           files or libraries appearing on the command line after the
           library in question do not affect whether the library is seen as
           needed.  This is similar to the rules for extraction of object
           files from archives.  --no-as-needed restores the default
           behaviour.
       --add-needed
       --no-add-needed
           These two options have been deprecated because of the similarity
           of their names to the --as-needed and --no-as-needed options.
           They have been replaced by --copy-dt-needed-entries and
           --no-copy-dt-needed-entries.
       -assert keyword
           This option is ignored for SunOS compatibility.
       -Bdynamic
       -dy
       -call_shared
           Link against dynamic libraries.  This is only meaningful on
           platforms for which shared libraries are supported.  This option
           is normally the default on such platforms.  The different
           variants of this option are for compatibility with various
           systems.  You may use this option multiple times on the command
           line: it affects library searching for -l options which follow
           it.
       -Bgroup
           Set the "DF_1_GROUP" flag in the "DT_FLAGS_1" entry in the
           dynamic section.  This causes the runtime linker to handle
           lookups in this object and its dependencies to be performed only
           inside the group.  --unresolved-symbols=report-all is implied.
           This option is only meaningful on ELF platforms which support
           shared libraries.
       -Bstatic
       -dn
       -non_shared
       -static
           Do not link against shared libraries.  This is only meaningful on
           platforms for which shared libraries are supported.  The
           different variants of this option are for compatibility with
           various systems.  You may use this option multiple times on the
           command line: it affects library searching for -l options which
           follow it.  This option also implies
           --unresolved-symbols=report-all.  This option can be used with
           -shared.  Doing so means that a shared library is being created
           but that all of the library's external references must be
           resolved by pulling in entries from static libraries.
       -Bsymbolic
           When creating a shared library, bind references to global symbols
           to the definition within the shared library, if any.  Normally,
           it is possible for a program linked against a shared library to
           override the definition within the shared library.  This option
           can also be used with the --export-dynamic option, when creating
           a position independent executable, to bind references to global
           symbols to the definition within the executable.  This option is
           only meaningful on ELF platforms which support shared libraries
           and position independent executables.
       -Bsymbolic-functions
           When creating a shared library, bind references to global
           function symbols to the definition within the shared library, if
           any.  This option can also be used with the --export-dynamic
           option, when creating a position independent executable, to bind
           references to global function symbols to the definition within
           the executable.  This option is only meaningful on ELF platforms
           which support shared libraries and position independent
           executables.
       --dynamic-list=dynamic-list-file
           Specify the name of a dynamic list file to the linker.  This is
           typically used when creating shared libraries to specify a list
           of global symbols whose references shouldn't be bound to the
           definition within the shared library, or creating dynamically
           linked executables to specify a list of symbols which should be
           added to the symbol table in the executable.  This option is only
           meaningful on ELF platforms which support shared libraries.
           The format of the dynamic list is the same as the version node
           without scope and node name.  See VERSION for more information.
       --dynamic-list-data
           Include all global data symbols to the dynamic list.
       --dynamic-list-cpp-new
           Provide the builtin dynamic list for C++ operator new and delete.
           It is mainly useful for building shared libstdc++.
       --dynamic-list-cpp-typeinfo
           Provide the builtin dynamic list for C++ runtime type
           identification.
       --check-sections
       --no-check-sections
           Asks the linker not to check section addresses after they have
           been assigned to see if there are any overlaps.  Normally the
           linker will perform this check, and if it finds any overlaps it
           will produce suitable error messages.  The linker does know
           about, and does make allowances for sections in overlays.  The
           default behaviour can be restored by using the command line
           switch --check-sections.  Section overlap is not usually checked
           for relocatable links.  You can force checking in that case by
           using the --check-sections option.
       --copy-dt-needed-entries
       --no-copy-dt-needed-entries
           This option affects the treatment of dynamic libraries referred
           to by DT_NEEDED tags inside ELF dynamic libraries mentioned on
           the command line.  Normally the linker won't add a DT_NEEDED tag
           to the output binary for each library mentioned in a DT_NEEDED
           tag in an input dynamic library.  With --copy-dt-needed-entries
           specified on the command line however any dynamic libraries that
           follow it will have their DT_NEEDED entries added.  The default
           behaviour can be restored with --no-copy-dt-needed-entries.
           This option also has an effect on the resolution of symbols in
           dynamic libraries.  With --copy-dt-needed-entries dynamic
           libraries mentioned on the command line will be recursively
           searched, following their DT_NEEDED tags to other libraries, in
           order to resolve symbols required by the output binary.  With the
           default setting however the searching of dynamic libraries that
           follow it will stop with the dynamic library itself.  No
           DT_NEEDED links will be traversed to resolve symbols.
       --cref
           Output a cross reference table.  If a linker map file is being
           generated, the cross reference table is printed to the map file.
           Otherwise, it is printed on the standard output.
           The format of the table is intentionally simple, so that it may
           be easily processed by a script if necessary.  The symbols are
           printed out, sorted by name.  For each symbol, a list of file
           names is given.  If the symbol is defined, the first file listed
           is the location of the definition.  If the symbol is defined as a
           common value then any files where this happens appear next.
           Finally any files that reference the symbol are listed.
       --no-define-common
           This option inhibits the assignment of addresses to common
           symbols.  The script command "INHIBIT_COMMON_ALLOCATION" has the
           same effect.
           The --no-define-common option allows decoupling the decision to
           assign addresses to Common symbols from the choice of the output
           file type; otherwise a non-Relocatable output type forces
           assigning addresses to Common symbols.  Using --no-define-common
           allows Common symbols that are referenced from a shared library
           to be assigned addresses only in the main program.  This
           eliminates the unused duplicate space in the shared library, and
           also prevents any possible confusion over resolving to the wrong
           duplicate when there are many dynamic modules with specialized
           search paths for runtime symbol resolution.
       --defsym=symbol=expression
           Create a global symbol in the output file, containing the
           absolute address given by expression.  You may use this option as
           many times as necessary to define multiple symbols in the command
           line.  A limited form of arithmetic is supported for the
           expression in this context: you may give a hexadecimal constant
           or the name of an existing symbol, or use "+" and "-" to add or
           subtract hexadecimal constants or symbols.  If you need more
           elaborate expressions, consider using the linker command language
           from a script.  Note: there should be no white space between
           symbol, the equals sign ("="), and expression.
       --demangle[=style]
       --no-demangle
           These options control whether to demangle symbol names in error
           messages and other output.  When the linker is told to demangle,
           it tries to present symbol names in a readable fashion: it strips
           leading underscores if they are used by the object file format,
           and converts C++ mangled symbol names into user readable names.
           Different compilers have different mangling styles.  The optional
           demangling style argument can be used to choose an appropriate
           demangling style for your compiler.  The linker will demangle by
           default unless the environment variable COLLECT_NO_DEMANGLE is
           set.  These options may be used to override the default.
       -Ifile
       --dynamic-linker=file
           Set the name of the dynamic linker.  This is only meaningful when
           generating dynamically linked ELF executables.  The default
           dynamic linker is normally correct; don't use this unless you
           know what you are doing.
       --no-dynamic-linker
           When producing an executable file, omit the request for a dynamic
           linker to be used at load-time.  This is only meaningful for ELF
           executables that contain dynamic relocations, and usually
           requires entry point code that is capable of processing these
           relocations.
       --fatal-warnings
       --no-fatal-warnings
           Treat all warnings as errors.  The default behaviour can be
           restored with the option --no-fatal-warnings.
       --force-exe-suffix
           Make sure that an output file has a .exe suffix.
           If a successfully built fully linked output file does not have a
           ".exe" or ".dll" suffix, this option forces the linker to copy
           the output file to one of the same name with a ".exe" suffix.
           This option is useful when using unmodified Unix makefiles on a
           Microsoft Windows host, since some versions of Windows won't run
           an image unless it ends in a ".exe" suffix.
       --gc-sections
       --no-gc-sections
           Enable garbage collection of unused input sections.  It is
           ignored on targets that do not support this option.  The default
           behaviour (of not performing this garbage collection) can be
           restored by specifying --no-gc-sections on the command line.
           Note that garbage collection for COFF and PE format targets is
           supported, but the implementation is currently considered to be
           experimental.
           --gc-sections decides which input sections are used by examining
           symbols and relocations.  The section containing the entry symbol
           and all sections containing symbols undefined on the command-line
           will be kept, as will sections containing symbols referenced by
           dynamic objects.  Note that when building shared libraries, the
           linker must assume that any visible symbol is referenced.  Once
           this initial set of sections has been determined, the linker
           recursively marks as used any section referenced by their
           relocations.  See --entry and --undefined.
           This option can be set when doing a partial link (enabled with
           option -r).  In this case the root of symbols kept must be
           explicitly specified either by an --entry or --undefined option
           or by a "ENTRY" command in the linker script.
       --print-gc-sections
       --no-print-gc-sections
           List all sections removed by garbage collection.  The listing is
           printed on stderr.  This option is only effective if garbage
           collection has been enabled via the --gc-sections) option.  The
           default behaviour (of not listing the sections that are removed)
           can be restored by specifying --no-print-gc-sections on the
           command line.
       --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.
       --no-keep-memory
           ld normally optimizes for speed over memory usage by caching the
           symbol tables of input files in memory.  This option tells ld to
           instead optimize for memory usage, by rereading the symbol tables
           as necessary.  This may be required if ld runs out of memory
           space while linking a large executable.
       --no-undefined
       -z defs
           Report unresolved symbol references from regular object files.
           This is done even if the linker is creating a non-symbolic shared
           library.  The switch --[no-]allow-shlib-undefined controls the
           behaviour for reporting unresolved references found in shared
           libraries being linked in.
       --allow-multiple-definition
       -z muldefs
           Normally when a symbol is defined multiple times, the linker will
           report a fatal error. These options allow multiple definitions
           and the first definition will be used.
       --allow-shlib-undefined
       --no-allow-shlib-undefined
           Allows or disallows undefined symbols in shared libraries.  This
           switch is similar to --no-undefined except that it determines the
           behaviour when the undefined symbols are in a shared library
           rather than a regular object file.  It does not affect how
           undefined symbols in regular object files are handled.
           The default behaviour is to report errors for any undefined
           symbols referenced in shared libraries if the linker is being
           used to create an executable, but to allow them if the linker is
           being used to create a shared library.
           The reasons for allowing undefined symbol references in shared
           libraries specified at link time are that:
           ·   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.
       --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.
       -qmagic
           This option is ignored for Linux compatibility.
       -Qy This option is ignored for SVR4 compatibility.
       --relax
       --no-relax
           An option with machine dependent effects.  This option is only
           supported on a few targets.
           On some platforms the --relax option performs target specific,
           global optimizations that become possible when the linker
           resolves addressing in the program, such as relaxing address
           modes, synthesizing new instructions, selecting shorter version
           of current instructions, and combining constant values.
           On some platforms these link time global optimizations may make
           symbolic debugging of the resulting executable impossible.  This
           is known to be the case for the Matsushita MN10200 and MN10300
           family of processors.
           On platforms where this is not supported, --relax is accepted,
           but ignored.
           On platforms where --relax is accepted the option --no-relax can
           be used to disable the feature.
       --retain-symbols-file=filename
           Retain only the symbols listed in the file filename, discarding
           all others.  filename is simply a flat file, with one symbol name
           per line.  This option is especially useful in environments (such
           as VxWorks) where a large global symbol table is accumulated
           gradually, to conserve run-time memory.
           --retain-symbols-file does not discard undefined symbols, or
           symbols needed for relocations.
           You may only specify --retain-symbols-file once in the command
           line.  It overrides -s and -S.
       -rpath=dir
           Add a directory to the runtime library search path.  This is used
           when linking an ELF executable with shared objects.  All -rpath
           arguments are concatenated and passed to the runtime linker,
           which uses them to locate shared objects at runtime.  The -rpath
           option is also used when locating shared objects which are needed
           by shared objects explicitly included in the link; see the
           description of the -rpath-link option.  If -rpath is not used
           when linking an ELF executable, the contents of the environment
           variable "LD_RUN_PATH" will be used if it is defined.
           The -rpath option may also be used on SunOS.  By default, on
           SunOS, the linker will form a runtime search path out of all the
           -L options it is given.  If a -rpath option is used, the runtime
           search path will be formed exclusively using the -rpath options,
           ignoring the -L options.  This can be useful when using gcc,
           which adds many -L options which may be on NFS mounted file
           systems.
           For compatibility with other ELF linkers, if the -R option is
           followed by a directory name, rather than a file name, it is
           treated as the -rpath option.
       -rpath-link=dir
           When using ELF or SunOS, one shared library may require another.
           This happens when an "ld -shared" link includes a shared library
           as one of the input files.
           When the linker encounters such a dependency when doing a non-
           shared, non-relocatable link, it will automatically try to locate
           the required shared library and include it in the link, if it is
           not included explicitly.  In such a case, the -rpath-link option
           specifies the first set of directories to search.  The
           -rpath-link option may specify a sequence of directory names
           either by specifying a list of names separated by colons, or by
           appearing multiple times.
           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.  The default directories, normally /lib and /usr/lib.
           8.  For a native linker on an ELF system, if the file
               /etc/ld.so.conf exists, the list of directories found in that
               file.
           If the required shared library is not found, the linker will
           issue a warning and continue with the link.
       -shared
       -Bshareable
           Create a shared library.  This is currently only supported on
           ELF, XCOFF and SunOS platforms.  On SunOS, the linker will
           automatically create a shared library if the -e option is not
           used and there are undefined symbols in the link.
       --sort-common
       --sort-common=ascending
       --sort-common=descending
           This option tells ld to sort the common symbols by alignment in
           ascending or descending order when it places them in the
           appropriate output sections.  The symbol alignments considered
           are sixteen-byte or larger, eight-byte, four-byte, two-byte, and
           one-byte. This is to prevent gaps between symbols due to
           alignment constraints.  If no sorting order is specified, then
           descending order is assumed.
       --sort-section=name
           This option will apply "SORT_BY_NAME" to all wildcard section
           patterns in the linker script.
       --sort-section=alignment
           This option will apply "SORT_BY_ALIGNMENT" to all wildcard
           section patterns in the linker script.
       --split-by-file[=size]
           Similar to --split-by-reloc but creates a new output section for
           each input file when size is reached.  size defaults to a size of
           1 if not given.
       --split-by-reloc[=count]
           Tries to creates extra sections in the output file so that no
           single output section in the file contains more than count
           relocations.  This is useful when generating huge relocatable
           files for downloading into certain real time kernels with the
           COFF object file format; since COFF cannot represent more than
           65535 relocations in a single section.  Note that this will fail
           to work with object file formats which do not support arbitrary
           sections.  The linker will not split up individual input sections
           for redistribution, so if a single input section contains more
           than count relocations one output section will contain that many
           relocations.  count defaults to a value of 32768.
       --stats
           Compute and display statistics about the operation of the linker,
           such as execution time and memory usage.
       --sysroot=directory
           Use directory as the location of the sysroot, overriding the
           configure-time default.  This option is only supported by linkers
           that were configured using --with-sysroot.
       --traditional-format
           For some targets, the output of ld is different in some ways from
           the output of some existing linker.  This switch requests ld to
           use the traditional format instead.
           For example, on SunOS, ld combines duplicate entries in the
           symbol string table.  This can reduce the size of an output file
           with full debugging information by over 30 percent.
           Unfortunately, the SunOS "dbx" program can not read the resulting
           program ("gdb" has no trouble).  The --traditional-format switch
           tells ld to not combine duplicate entries.
       --section-start=sectionname=org
           Locate a section in the output file at the absolute address given
           by org.  You may use this option as many times as necessary to
           locate multiple sections in the command line.  org must be a
           single hexadecimal integer; for compatibility with other linkers,
           you may omit the leading 0x usually associated with hexadecimal
           values.  Note: there should be no white space between
           sectionname, the equals sign ("="), and org.
       -Tbss=org
       -Tdata=org
       -Ttext=org
           Same as --section-start, with ".bss", ".data" or ".text" as the
           sectionname.
       -Ttext-segment=org
           When creating an ELF executable, it will set the address of the
           first byte of the text segment.
       -Trodata-segment=org
           When creating an ELF executable or shared object for a target
           where the read-only data is in its own segment separate from the
           executable text, it will set the address of the first byte of the
           read-only data segment.
       -Tldata-segment=org
           When creating an ELF executable or shared object for x86-64
           medium memory model, it will set the address of the first byte of
           the ldata segment.
       --unresolved-symbols=method
           Determine how to handle unresolved symbols.  There are four
           possible values for method:
           ignore-all
               Do not report any unresolved symbols.
           report-all
               Report all unresolved symbols.  This is the default.
           ignore-in-object-files
               Report unresolved symbols that are contained in shared
               libraries, but ignore them if they come from regular object
               files.
           ignore-in-shared-libs
               Report unresolved symbols that come from regular object
               files, but ignore them if they come from shared libraries.
               This can be useful when creating a dynamic binary and it is
               known that all the shared libraries that it should be
               referencing are included on the linker's command line.
           The behaviour for shared libraries on their own can also be
           controlled by the --[no-]allow-shlib-undefined option.
           Normally the linker will generate an error message for each
           reported unresolved symbol but the option
           --warn-unresolved-symbols can change this to a warning.
       --dll-verbose
       --verbose[=NUMBER]
           Display the version number for ld and list the linker emulations
           supported.  Display which input files can and cannot be opened.
           Display the linker script being used by the linker. If the
           optional NUMBER argument > 1, plugin symbol status will also be
           displayed.
       --version-script=version-scriptfile
           Specify the name of a version script to the linker.  This is
           typically used when creating shared libraries to specify
           additional information about the version hierarchy for the
           library being created.  This option is only fully supported on
           ELF platforms which support shared libraries; see VERSION.  It is
           partially supported on PE platforms, which can use version
           scripts to filter symbol visibility in auto-export mode: any
           symbols marked local in the version script will not be exported.
       --warn-common
           Warn when a common symbol is combined with another common symbol
           or with a symbol definition.  Unix linkers allow this somewhat
           sloppy practice, but linkers on some other operating systems do
           not.  This option allows you to find potential problems from
           combining global symbols.  Unfortunately, some C libraries use
           this practice, so you may get some warnings about symbols in the
           libraries as well as in your programs.
           There are three kinds of global symbols, illustrated here by C
           examples:
           int i = 1;
               A definition, which goes in the initialized data section of
               the output file.
           extern int i;
               An undefined reference, which does not allocate space.  There
               must be either a definition or a common symbol for the
               variable somewhere.
           int i;
               A common symbol.  If there are only (one or more) common
               symbols for a variable, it goes in the uninitialized data
               area of the output file.  The linker merges multiple common
               symbols for the same variable into a single symbol.  If they
               are of different sizes, it picks the largest size.  The
               linker turns a common symbol into a declaration, if there is
               a definition of the same variable.
           The --warn-common option can produce five kinds of warnings.
           Each warning consists of a pair of lines: the first describes the
           symbol just encountered, and the second describes the previous
           symbol encountered with the same name.  One or both of the two
           symbols will be a common symbol.
           1.  Turning a common symbol into a reference, because there is
               already a definition for the symbol.
                       <file>(<section>): warning: common of `<symbol>'
                          overridden by definition
                       <file>(<section>): warning: defined here
           2.  Turning a common symbol into a reference, because a later
               definition for the symbol is encountered.  This is the same
               as the previous case, except that the symbols are encountered
               in a different order.
                       <file>(<section>): warning: definition of `<symbol>'
                          overriding common
                       <file>(<section>): warning: common is here
           3.  Merging a common symbol with a previous same-sized common
               symbol.
                       <file>(<section>): warning: multiple common
                          of `<symbol>'
                       <file>(<section>): warning: previous common is here
           4.  Merging a common symbol with a previous larger common symbol.
                       <file>(<section>): warning: common of `<symbol>'
                          overridden by larger common
                       <file>(<section>): warning: larger common is here
           5.  Merging a common symbol with a previous smaller common
               symbol.  This is the same as the previous case, except that
               the symbols are encountered in a different order.
                       <file>(<section>): warning: common of `<symbol>'
                          overriding smaller common
                       <file>(<section>): warning: smaller common is here
       --warn-constructors
           Warn if any global constructors are used.  This is only useful
           for a few object file formats.  For formats like COFF or ELF, the
           linker can not detect the use of global constructors.
       --warn-multiple-gp
           Warn if multiple global pointer values are required in the output
           file.  This is only meaningful for certain processors, such as
           the Alpha.  Specifically, some processors put large-valued
           constants in a special section.  A special register (the global
           pointer) points into the middle of this section, so that
           constants can be loaded efficiently via a base-register relative
           addressing mode.  Since the offset in base-register relative mode
           is fixed and relatively small (e.g., 16 bits), this limits the
           maximum size of the constant pool.  Thus, in large programs, it
           is often necessary to use multiple global pointer values in order
           to be able to address all possible constants.  This option causes
           a warning to be issued whenever this case occurs.
       --warn-once
           Only warn once for each undefined symbol, rather than once per
           module which refers to it.
       --warn-section-align
           Warn if the address of an output section is changed because of
           alignment.  Typically, the alignment will be set by an input
           section.  The address will only be changed if it not explicitly
           specified; that is, if the "SECTIONS" command does not specify a
           start address for the section.
       --warn-shared-textrel
           Warn if the linker adds a DT_TEXTREL to a shared object.
       --warn-alternate-em
           Warn if an object has alternate ELF machine code.
       --warn-unresolved-symbols
           If the linker is going to report an unresolved symbol (see the
           option --unresolved-symbols) it will normally generate an error.
           This option makes it generate a warning instead.
       --error-unresolved-symbols
           This restores the linker's default behaviour of generating errors
           when it is reporting unresolved symbols.
       --whole-archive
           For each archive mentioned on the command line after the
           --whole-archive option, include every object file in the archive
           in the link, rather than searching the archive for the required
           object files.  This is normally used to turn an archive file into
           a shared library, forcing every object to be included in the
           resulting shared library.  This option may be used more than
           once.
           Two notes when using this option from gcc: First, gcc doesn't
           know about this option, so you have to use -Wl,-whole-archive.
           Second, don't forget to use -Wl,-no-whole-archive after your list
           of archives, because gcc will add its own list of archives to
           your link and you may not want this flag to affect those as well.
       --wrap=symbol
           Use a wrapper function for symbol.  Any undefined reference to
           symbol will be resolved to "__wrap_symbol".  Any undefined
           reference to "__real_symbol" will be resolved to symbol.
           This can be used to provide a wrapper for a system function.  The
           wrapper function should be called "__wrap_symbol".  If it wishes
           to call the system function, it should call "__real_symbol".
           Here is a trivial example:
                   void *
                   __wrap_malloc (size_t c)
                   {
                     printf ("malloc called with %zu\n", c);
                     return __real_malloc (c);
                   }
           If you link other code with this file using --wrap malloc, then
           all calls to "malloc" will call the function "__wrap_malloc"
           instead.  The call to "__real_malloc" in "__wrap_malloc" will
           call the real "malloc" function.
           You may wish to provide a "__real_malloc" function as well, so
           that links without the --wrap option will succeed.  If you do
           this, you should not put the definition of "__real_malloc" in the
           same file as "__wrap_malloc"; if you do, the assembler may
           resolve the call before the linker has a chance to wrap it to
           "malloc".
       --eh-frame-hdr
       --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.
       --enable-new-dtags
       --disable-new-dtags
           This linker can create the new dynamic tags in ELF. But the older
           ELF systems may not understand them. If you specify
           --enable-new-dtags, the new dynamic tags will be created as
           needed and older dynamic tags will be omitted.  If you specify
           --disable-new-dtags, no new dynamic tags will be created. By
           default, the new dynamic tags are not created. Note that those
           options are only available for ELF systems.
       --hash-size=number
           Set the default size of the linker's hash tables to a prime
           number close to number.  Increasing this value can reduce the
           length of time it takes the linker to perform its tasks, at the
           expense of increasing the linker's memory requirements.
           Similarly reducing this value can reduce the memory requirements
           at the expense of speed.
       --hash-style=style
           Set the type of linker's hash table(s).  style can be either
           "sysv" for classic ELF ".hash" section, "gnu" for new style GNU
           ".gnu.hash" section or "both" for both the classic ELF ".hash"
           and new style GNU ".gnu.hash" hash tables.  The default is
           "sysv".
       --compress-debug-sections=none
       --compress-debug-sections=zlib
       --compress-debug-sections=zlib-gnu
       --compress-debug-sections=zlib-gabi
           On ELF platforms, these options control how DWARF debug sections
           are compressed using zlib.
           --compress-debug-sections=none doesn't compress DWARF debug
           sections.  --compress-debug-sections=zlib-gnu compresses DWARF
           debug sections and 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.
           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.
       --build-id
       --build-id=style
           Request the creation of a ".note.gnu.build-id" ELF note section
           or a ".buildid" COFF section.  The contents of the note are
           unique bits identifying this linked file.  style can be "uuid" to
           use 128 random bits, "sha1" to use a 160-bit SHA1 hash on the
           normative parts of the output contents, "md5" to use a 128-bit
           MD5 hash on the normative parts of the output contents, or
           "0xhexstring" to use a chosen bit string specified as an even
           number of hexadecimal digits ("-" and ":" characters between
           digit pairs are ignored).  If style is omitted, "sha1" is used.
           The "md5" and "sha1" styles produces an identifier that is always
           the same in an identical output file, but will be unique among
           all nonidentical output files.  It is not intended to be compared
           as a checksum for the file's contents.  A linked file may be
           changed later by other tools, but the build ID bit string
           identifying the original linked file does not change.
           Passing "none" for style disables the setting from any
           "--build-id" options earlier on the command line.
       The i386 PE linker supports the -shared option, which causes the
       output to be a dynamically linked library (DLL) instead of a normal
       executable.  You should name the output "*.dll" when you use this
       option.  In addition, the linker fully supports the standard "*.def"
       files, which may be specified on the linker command line like an
       object file (in fact, it should precede archives it exports symbols
       from, to ensure that they get linked in, just like a normal object
       file).
       In addition to the options common to all targets, the i386 PE linker
       support additional command line options that are specific to the i386
       PE target.  Options that take values may be separated from their
       values by either a space or an equals sign.
       --add-stdcall-alias
           If given, symbols with a stdcall suffix (@nn) will be exported
           as-is and also with the suffix stripped.  [This option is
           specific to the i386 PE targeted port of the linker]
       --base-file file
           Use file as the name of a file in which to save the base
           addresses of all the relocations needed for generating DLLs with
           dlltool.  [This is an i386 PE specific option]
       --dll
           Create a DLL instead of a regular executable.  You may also use
           -shared or specify a "LIBRARY" in a given ".def" file.  [This
           option is specific to the i386 PE targeted port of the linker]
       --enable-long-section-names
       --disable-long-section-names
           The PE variants of the COFF object format add an extension that
           permits the use of section names longer than eight characters,
           the normal limit for COFF.  By default, these names are only
           allowed in object files, as fully-linked executable images do not
           carry the COFF string table required to support the longer names.
           As a GNU extension, it is possible to allow their use in
           executable images as well, or to (probably pointlessly!)
           disallow it in object files, by using these two options.
           Executable images generated with these long section names are
           slightly non-standard, carrying as they do a string table, and
           may generate confusing output when examined with non-GNU PE-aware
           tools, such as file viewers and dumpers.  However, GDB relies on
           the use of PE long section names to find Dwarf-2 debug
           information sections in an executable image at runtime, and so if
           neither option is specified on the command-line, ld will enable
           long section names, overriding the default and technically
           correct behaviour, when it finds the presence of debug
           information while linking an executable image and not stripping
           symbols.  [This option is valid for all PE targeted ports of the
           linker]
       --enable-stdcall-fixup
       --disable-stdcall-fixup
           If the link finds a symbol that it cannot resolve, it will
           attempt to do "fuzzy linking" by looking for another defined
           symbol that differs only in the format of the symbol name (cdecl
           vs stdcall) and will resolve that symbol by linking to the match.
           For example, the undefined symbol "_foo" might be linked to the
           function "_foo@12", or the undefined symbol "_bar@16" might be
           linked to the function "_bar".  When the linker does this, it
           prints a warning, since it normally should have failed to link,
           but sometimes import libraries generated from third-party dlls
           may need this feature to be usable.  If you specify
           --enable-stdcall-fixup, this feature is fully enabled and
           warnings are not printed.  If you specify
           --disable-stdcall-fixup, this feature is disabled and such
           mismatches are considered to be errors.  [This option is specific
           to the i386 PE targeted port of the linker]
       --leading-underscore
       --no-leading-underscore
           For most targets default symbol-prefix is an underscore and is
           defined in target's description. By this option it is possible to
           disable/enable the default underscore symbol-prefix.
       --export-all-symbols
           If given, all global symbols in the objects used to build a DLL
           will be exported by the DLL.  Note that this is the default if
           there otherwise wouldn't be any exported symbols.  When symbols
           are explicitly exported via DEF files or implicitly exported via
           function attributes, the default is to not export anything else
           unless this option is given.  Note that the symbols "DllMain@12",
           "DllEntryPoint@0", "DllMainCRTStartup@12", and "impure_ptr" will
           not be automatically exported.  Also, symbols imported from other
           DLLs will not be re-exported, nor will symbols specifying the
           DLL's internal layout such as those beginning with "_head_" or
           ending with "_iname".  In addition, no symbols from "libgcc",
           "libstd++", "libmingw32", or "crtX.o" will be exported.  Symbols
           whose names begin with "__rtti_" or "__builtin_" will not be
           exported, to help with C++ DLLs.  Finally, there is an extensive
           list of cygwin-private symbols that are not exported (obviously,
           this applies on when building DLLs for cygwin targets).  These
           cygwin-excludes are: "_cygwin_dll_entry@12",
           "_cygwin_crt0_common@8", "_cygwin_noncygwin_dll_entry@12",
           "_fmode", "_impure_ptr", "cygwin_attach_dll", "cygwin_premain0",
           "cygwin_premain1", "cygwin_premain2", "cygwin_premain3", and
           "environ".  [This option is specific to the i386 PE targeted port
           of the linker]
       --exclude-symbols symbol,symbol,...
           Specifies a list of symbols which should not be automatically
           exported.  The symbol names may be delimited by commas or colons.
           [This option is specific to the i386 PE targeted port of the
           linker]
       --exclude-all-symbols
           Specifies no symbols should be automatically exported.  [This
           option is specific to the i386 PE targeted port of the linker]
       --file-alignment
           Specify the file alignment.  Sections in the file will always
           begin at file offsets which are multiples of this number.  This
           defaults to 512.  [This option is specific to the i386 PE
           targeted port of the linker]
       --heap reserve
       --heap reserve,commit
           Specify the number of bytes of memory to reserve (and optionally
           commit) to be used as heap for this program.  The default is 1MB
           reserved, 4K committed.  [This option is specific to the i386 PE
           targeted port of the linker]
       --image-base value
           Use value as the base address of your program or dll.  This is
           the lowest memory location that will be used when your program or
           dll is loaded.  To reduce the need to relocate and improve
           performance of your dlls, each should have a unique base address
           and not overlap any other dlls.  The default is 0x400000 for
           executables, and 0x10000000 for dlls.  [This option is specific
           to the i386 PE targeted port of the linker]
       --kill-at
           If given, the stdcall suffixes (@nn) will be stripped from
           symbols before they are exported.  [This option is specific to
           the i386 PE targeted port of the linker]
       --large-address-aware
           If given, the appropriate bit in the "Characteristics" field of
           the COFF header is set to indicate that this executable supports
           virtual addresses greater than 2 gigabytes.  This should be used
           in conjunction with the /3GB or /USERVA=value megabytes switch in
           the "[operating systems]" section of the BOOT.INI.  Otherwise,
           this bit has no effect.  [This option is specific to PE targeted
           ports of the linker]
       --disable-large-address-aware
           Reverts the effect of a previous --large-address-aware option.
           This is useful if --large-address-aware is always set by the
           compiler driver (e.g. Cygwin gcc) and the executable does not
           support virtual addresses greater than 2 gigabytes.  [This option
           is specific to PE targeted ports of the linker]
       --major-image-version value
           Sets the major number of the "image version".  Defaults to 1.
           [This option is specific to the i386 PE targeted port of the
           linker]
       --major-os-version value
           Sets the major number of the "os version".  Defaults to 4.  [This
           option is specific to the i386 PE targeted port of the linker]
       --major-subsystem-version value
           Sets the major number of the "subsystem version".  Defaults to 4.
           [This option is specific to the i386 PE targeted port of the
           linker]
       --minor-image-version value
           Sets the minor number of the "image version".  Defaults to 0.
           [This option is specific to the i386 PE targeted port of the
           linker]
       --minor-os-version value
           Sets the minor number of the "os version".  Defaults to 0.  [This
           option is specific to the i386 PE targeted port of the linker]
       --minor-subsystem-version value
           Sets the minor number of the "subsystem version".  Defaults to 0.
           [This option is specific to the i386 PE targeted port of the
           linker]
       --output-def file
           The linker will create the file file which will contain a DEF
           file corresponding to the DLL the linker is generating.  This DEF
           file (which should be called "*.def") may be used to create an
           import library with "dlltool" or may be used as a reference to
           automatically or implicitly exported symbols.  [This option is
           specific to the i386 PE targeted port of the linker]
       --enable-auto-image-base
       --enable-auto-image-base=value
           Automatically choose the image base for DLLs, optionally starting
           with base value, unless one is specified using the "--image-base"
           argument.  By using a hash generated from the dllname to create
           unique image bases for each DLL, in-memory collisions and
           relocations which can delay program execution are avoided.  [This
           option is specific to the i386 PE targeted port of the linker]
       --disable-auto-image-base
           Do not automatically generate a unique image base.  If there is
           no user-specified image base ("--image-base") then use the
           platform default.  [This option is specific to the i386 PE
           targeted port of the linker]
       --dll-search-prefix string
           When linking dynamically to a dll without an import library,
           search for "<string><basename>.dll" in preference to
           "lib<basename>.dll". This behaviour allows easy distinction
           between DLLs built for the various "subplatforms": native,
           cygwin, uwin, pw, etc.  For instance, cygwin DLLs typically use
           "--dll-search-prefix=cyg".  [This option is specific to the i386
           PE targeted port of the linker]
       --enable-auto-import
           Do sophisticated linking of "_symbol" to "__imp__symbol" for DATA
           imports from DLLs, and create the necessary thunking symbols when
           building the import libraries with those DATA exports. Note: Use
           of the 'auto-import' extension will cause the text section of the
           image file to be made writable. This does not conform to the PE-
           COFF format specification published by Microsoft.
           Note - use of the 'auto-import' extension will also cause read
           only data which would normally be placed into the .rdata section
           to be placed into the .data section instead.  This is in order to
           work around a problem with consts that is described here:
           http://www.cygwin.com/ml/cygwin/2004-09/msg01101.html
           Using 'auto-import' generally will 'just work' -- but sometimes
           you may see this message:
           "variable '<var>' can't be auto-imported. Please read the
           documentation for ld's "--enable-auto-import" for details."
           This message occurs when some (sub)expression accesses an address
           ultimately given by the sum of two constants (Win32 import tables
           only allow one).  Instances where this may occur include accesses
           to member fields of struct variables imported from a DLL, as well
           as using a constant index into an array variable imported from a
           DLL.  Any multiword variable (arrays, structs, long long, etc)
           may trigger this error condition.  However, regardless of the
           exact data type of the offending exported variable, ld will
           always detect it, issue the warning, and exit.
           There are several ways to address this difficulty, regardless of
           the data type of the exported variable:
           One way is to use --enable-runtime-pseudo-reloc switch. This
           leaves the task of adjusting references in your client code for
           runtime environment, so this method works only when runtime
           environment supports this feature.
           A second solution is to force one of the 'constants' to be a
           variable -- that is, unknown and un-optimizable at compile time.
           For arrays, there are two possibilities: a) make the indexee (the
           array's address) a variable, or b) make the 'constant' index a
           variable.  Thus:
                   extern type extern_array[];
                   extern_array[1] -->
                      { volatile type *t=extern_array; t[1] }
           or
                   extern type extern_array[];
                   extern_array[1] -->
                      { volatile int t=1; extern_array[t] }
           For structs (and most other multiword data types) the only option
           is to make the struct itself (or the long long, or the ...)
           variable:
                   extern struct s extern_struct;
                   extern_struct.field -->
                      { volatile struct s *t=&extern_struct; t->field }
           or
                   extern long long extern_ll;
                   extern_ll -->
                     { volatile long long * local_ll=&extern_ll; *local_ll }
           A third method of dealing with this difficulty is to abandon
           'auto-import' for the offending symbol and mark it with
           "__declspec(dllimport)".  However, in practice that requires
           using compile-time #defines to indicate whether you are building
           a DLL, building client code that will link to the DLL, or merely
           building/linking to a static library.   In making the choice
           between the various methods of resolving the 'direct address with
           constant offset' problem, you should consider typical real-world
           usage:
           Original:
                   --foo.h
                   extern int arr[];
                   --foo.c
                   #include "foo.h"
                   void main(int argc, char **argv){
                     printf("%d\n",arr[1]);
                   }
           Solution 1:
                   --foo.h
                   extern int arr[];
                   --foo.c
                   #include "foo.h"
                   void main(int argc, char **argv){
                     /* This workaround is for win32 and cygwin; do not "optimize" */
                     volatile int *parr = arr;
                     printf("%d\n",parr[1]);
                   }
           Solution 2:
                   --foo.h
                   /* Note: auto-export is assumed (no __declspec(dllexport)) */
                   #if (defined(_WIN32) || defined(__CYGWIN__)) && \
                     !(defined(FOO_BUILD_DLL) || defined(FOO_STATIC))
                   #define FOO_IMPORT __declspec(dllimport)
                   #else
                   #define FOO_IMPORT
                   #endif
                   extern FOO_IMPORT int arr[];
                   --foo.c
                   #include "foo.h"
                   void main(int argc, char **argv){
                     printf("%d\n",arr[1]);
                   }
           A fourth way to avoid this problem is to re-code your library to
           use a functional interface rather than a data interface for the
           offending variables (e.g. set_foo() and get_foo() accessor
           functions).  [This option is specific to the i386 PE targeted
           port of the linker]
       --disable-auto-import
           Do not attempt to do sophisticated linking of "_symbol" to
           "__imp__symbol" for DATA imports from DLLs.  [This option is
           specific to the i386 PE targeted port of the linker]
       --enable-runtime-pseudo-reloc
           If your code contains expressions described in
           --enable-auto-import section, that is, DATA imports from DLL with
           non-zero offset, this switch will create a vector of 'runtime
           pseudo relocations' which can be used by runtime environment to
           adjust references to such data in your client code.  [This option
           is specific to the i386 PE targeted port of the linker]
       --disable-runtime-pseudo-reloc
           Do not create pseudo relocations for non-zero offset DATA imports
           from DLLs.  [This option is specific to the i386 PE targeted port
           of the linker]
       --enable-extra-pe-debug
           Show additional debug info related to auto-import symbol
           thunking.  [This option is specific to the i386 PE targeted port
           of the linker]
       --section-alignment
           Sets the section alignment.  Sections in memory will always begin
           at addresses which are a multiple of this number.  Defaults to
           0x1000.  [This option is specific to the i386 PE targeted port of
           the linker]
       --stack reserve
       --stack reserve,commit
           Specify the number of bytes of memory to reserve (and optionally
           commit) to be used as stack for this program.  The default is 2MB
           reserved, 4K committed.  [This option is specific to the i386 PE
           targeted port of the linker]
       --subsystem which
       --subsystem which:major
       --subsystem which:major.minor
           Specifies the subsystem under which your program will execute.
           The legal values for which are "native", "windows", "console",
           "posix", and "xbox".  You may optionally set the subsystem
           version also.  Numeric values are also accepted for which.  [This
           option is specific to the i386 PE targeted port of the linker]
           The following options set flags in the "DllCharacteristics" field
           of the PE file header: [These options are specific to PE targeted
           ports of the linker]
       --high-entropy-va
           Image is compatible with 64-bit address space layout
           randomization (ASLR).
       --dynamicbase
           The image base address may be relocated using address space
           layout randomization (ASLR).  This feature was introduced with MS
           Windows Vista for i386 PE targets.
       --forceinteg
           Code integrity checks are enforced.
       --nxcompat
           The image is compatible with the Data Execution Prevention.  This
           feature was introduced with MS Windows XP SP2 for i386 PE
           targets.
       --no-isolation
           Although the image understands isolation, do not isolate the
           image.
       --no-seh
           The image does not use SEH. No SE handler may be called from this
           image.
       --no-bind
           Do not bind this image.
       --wdmdriver
           The driver uses the MS Windows Driver Model.
       --tsaware
           The image is Terminal Server aware.
       --insert-timestamp
       --no-insert-timestamp
           Insert a real timestamp into the image.  This is the default
           behaviour as it matches legacy code and it means that the image
           will work with other, proprietary tools.  The problem with this
           default is that it will result in slightly different images being
           produced each time the same sources are linked.  The option
           --no-insert-timestamp can be used to insert a zero value for the
           timestamp, this ensuring that binaries produced from identical
           sources will compare identically.
       The C6X uClinux target uses a binary format called DSBT to support
       shared libraries.  Each shared library in the system needs to have a
       unique index; all executables use an index of 0.
       --dsbt-size size
           This option sets the number of entries in the DSBT of the current
           executable or shared library to size.  The default is to create a
           table with 64 entries.
       --dsbt-index index
           This option sets the DSBT index of the current executable or
           shared library to index.  The default is 0, which is appropriate
           for generating executables.  If a shared library is generated
           with a DSBT index of 0, the "R_C6000_DSBT_INDEX" relocs are
           copied into the output file.
           The --no-merge-exidx-entries switch disables the merging of
           adjacent exidx entries in frame unwind info.
       The 68HC11 and 68HC12 linkers support specific options to control the
       memory bank switching mapping and trampoline code generation.
       --no-trampoline
           This option disables the generation of trampoline. By default a
           trampoline is generated for each far function which is called
           using a "jsr" instruction (this happens when a pointer to a far
           function is taken).
       --bank-window name
           This option indicates to the linker the name of the memory region
           in the MEMORY specification that describes the memory bank
           window.  The definition of such region is then used by the linker
           to compute paging and addresses within the memory window.
       The following options are supported to control handling of GOT
       generation when linking for 68K targets.
       --got=type
           This option tells the linker which GOT generation scheme to use.
           type should be one of single, negative, multigot or target.  For
           more information refer to the Info entry for ld.
       The following options are supported to control microMIPS instruction
       generation 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.

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) 1991-2017 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-2.28.tar.gz fetched from
       ⟨https://ftp.gnu.org/gnu/binutils/⟩ on 2017-07-05.  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 man-pages@man7.org
binutils-2.28                    2017-03-02                            LD(1)

Pages that refer to this page: uselib(2)backtrace(3)dlopen(3)elf(5)ld.so(8)