ld.texinfo

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@item -d
@itemx -dc
@itemx -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 @samp{-r}).  The
script command @code{FORCE_COMMON_ALLOCATION} has the same effect.
@xref{Miscellaneous Commands}.

@cindex entry point, from command line
@kindex -e @var{entry}
@kindex --entry=@var{entry}
@item -e @var{entry}
@itemx --entry=@var{entry}
Use @var{entry} as the explicit symbol for beginning execution of your
program, rather than the default entry point.  If there is no symbol
named @var{entry}, the linker will try to parse @var{entry} as a number,
and use that as the entry address (the number will be interpreted in
base 10; you may use a leading @samp{0x} for base 16, or a leading
@samp{0} for base 8).  @xref{Entry Point}, for a discussion of defaults
and other ways of specifying the entry point.

@cindex dynamic symbol table
@kindex -E
@kindex --export-dynamic
@item -E
@itemx --export-dynamic
When creating a dynamically linked executable, add all symbols to the
dynamic symbol table.  The dynamic symbol table is the set of symbols
which are visible from dynamic objects at run time.

If you do not use this option, the dynamic symbol table will normally
contain only those symbols which are referenced by some dynamic object
mentioned in the link.

If you use @code{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.

@cindex big-endian objects
@cindex endianness
@kindex -EB
@item -EB
Link big-endian objects.  This affects the default output format.

@cindex little-endian objects
@kindex -EL
@item -EL
Link little-endian objects.  This affects the default output format.

@kindex -f
@kindex --auxiliary
@item -f
@itemx --auxiliary @var{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 @var{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
@var{name}.  If there is one, it will be used instead of the definition
in the filter object.  The shared object @var{name} need not exist.
Thus the shared object @var{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.

@kindex -F
@kindex --filter
@item -F @var{name}
@itemx --filter @var{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 @var{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 @var{name}.  Thus the filter object can be
used to select a subset of the symbols provided by the object
@var{name}.

Some older linkers used the @code{-F} option throughout a compilation
toolchain for specifying object-file format for both input and output
object files.  The @sc{gnu} linker uses other mechanisms for this
purpose: the @code{-b}, @code{--format}, @code{--oformat} options, the
@code{TARGET} command in linker scripts, and the @code{GNUTARGET}
environment variable.  The @sc{gnu} linker will ignore the @code{-F}
option when not creating an ELF shared object.

@cindex finalization function
@kindex -fini
@item -fini @var{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 @code{_fini} as
the function to call.

@kindex -g
@item -g
Ignored.  Provided for compatibility with other tools.

@kindex -G
@kindex --gpsize
@cindex object size
@item -G@var{value}
@itemx --gpsize=@var{value}
Set the maximum size of objects to be optimized using the GP register to
@var{size}.  This is only meaningful for object file formats such as
MIPS ECOFF which supports putting large and small objects into different
sections.  This is ignored for other object file formats.

@cindex runtime library name
@kindex -h@var{name}
@kindex -soname=@var{name}
@item -h@var{name}
@itemx -soname=@var{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.

@kindex -i
@cindex incremental link
@item -i
Perform an incremental link (same as option @samp{-r}).

@cindex initialization function
@kindex -init
@item -init @var{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 @code{_init} as the
function to call.

@cindex archive files, from cmd line
@kindex -l@var{archive}
@kindex --library=@var{archive}
@item -l@var{archive}
@itemx --library=@var{archive}
Add archive file @var{archive} to the list of files to link.  This
option may be used any number of times.  @code{ld} will search its
path-list for occurrences of @code{lib@var{archive}.a} for every
@var{archive} specified.

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

The linker will search an archive only once, at the location where it is
specified on the command line.  If the archive defines a 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 @code{-(} 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.

@ifset GENERIC
This type of archive searching is standard for Unix linkers.  However,
if you are using @code{ld} on AIX, note that it is different from the
behaviour of the AIX linker.
@end ifset

@cindex search directory, from cmd line
@kindex -L@var{dir}
@kindex --library-path=@var{dir}
@item -L@var{searchdir}
@itemx --library-path=@var{searchdir}
Add path @var{searchdir} to the list of paths that @code{ld} will search
for archive libraries and @code{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
@code{-L} options apply to all @code{-l} options, regardless of the
order in which the options appear.

@ifset UsesEnvVars
The default set of paths searched (without being specified with
@samp{-L}) depends on which emulation mode @code{ld} is using, and in
some cases also on how it was configured.  @xref{Environment}.
@end ifset

The paths can also be specified in a link script with the
@code{SEARCH_DIR} command.  Directories specified this way are searched
at the point in which the linker script appears in the command line.

@cindex emulation
@kindex -m @var{emulation}
@item -m@var{emulation}
Emulate the @var{emulation} linker.  You can list the available
emulations with the @samp{--verbose} or @samp{-V} options.

If the @samp{-m} option is not used, the emulation is taken from the
@code{LDEMULATION} environment variable, if that is defined.

Otherwise, the default emulation depends upon how the linker was
configured.

@cindex link map
@kindex -M
@kindex --print-map
@item -M
@itemx --print-map
Print a link map to the standard output.  A link map provides
information about the link, including the following:

@itemize @bullet
@item
Where object files and symbols are mapped into memory.
@item
How common symbols are allocated.
@item
All archive members included in the link, with a mention of the symbol
which caused the archive member to be brought in.
@end itemize

@kindex -n
@cindex read-only text
@cindex NMAGIC
@kindex --nmagic
@item -n
@itemx --nmagic
Turn off page alignment of sections, and mark the output as
@code{NMAGIC} if possible.

@kindex -N
@kindex --omagic
@cindex read/write from cmd line
@cindex OMAGIC
@item -N
@itemx --omagic
Set the text and data sections to be readable and writable.  Also, do
not page-align the data segment.  If the output format supports Unix
style magic numbers, mark the output as @code{OMAGIC}.

@kindex -o @var{output}
@kindex --output=@var{output}
@cindex naming the output file
@item -o @var{output}
@itemx --output=@var{output}
Use @var{output} as the name for the program produced by @code{ld}; if this
option is not specified, the name @file{a.out} is used by default.  The
script command @code{OUTPUT} can also specify the output file name.

@kindex -O @var{level}
@cindex generating optimized output
@item -O @var{level}
If @var{level} is a numeric values greater than zero @code{ld} optimizes
the output.  This might take significantly longer and therefore probably
should only be enabled for the final binary.

@kindex -q
@kindex --emit-relocs
@cindex retain relocations in final executable
@item -q
@itemx --emit-relocs
Leave relocation sections and contents in fully linked exececutables.
Post link analysis and optimization tools may need this information in
order to perform correct modifications of executables.  This results
in larger executables.

@cindex partial link
@cindex relocatable output
@kindex -r
@kindex --relocateable
@item -r
@itemx --relocateable
Generate relocatable output---i.e., generate an output file that can in
turn serve as input to @code{ld}.  This is often called @dfn{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
@code{OMAGIC}.
@c ; see @code{-N}.
If this option is not specified, an absolute file is produced.  When
linking C++ programs, this option @emph{will not} resolve references to
constructors; to do that, use @samp{-Ur}.

This option does the same thing as @samp{-i}.

@kindex -R @var{file}
@kindex --just-symbols=@var{file}
@cindex symbol-only input
@item -R @var{filename}
@itemx --just-symbols=@var{filename}
Read symbol names and their addresses from @var{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 @code{-R} option is
followed by a directory name, rather than a file name, it is treated as
the @code{-rpath} option.

@kindex -s
@kindex --strip-all
@cindex strip all symbols
@item -s
@itemx --strip-all
Omit all symbol information from the output file.

@kindex -S
@kindex --strip-debug
@cindex strip debugger symbols
@item -S
@itemx --strip-debug
Omit debugger symbol information (but not all symbols) from the output file.

@kindex -t
@kindex --trace
@cindex input files, displaying
@item -t
@itemx --trace
Print the names of the input files as @code{ld} processes them.

@kindex -T @var{script}