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<A NAME="PAGENUM-289"><P>Page 289</P></A>
<TABLE>
<TR><TD>
</TD><TD>
You can meaningfully use _A more than once on a command line, if an architecture
family allows combination of target architectures; each use will add another pair of name
variants to search for when _l specifies a library.
</TD></TR><TR><TD>
_b input-format
</TD><TD>
Specify the binary format for input object FILES that follow this option on the command
line. You don't usually need to specify this, as ld
is 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
partic-ular format supported by the BFD libraries.
</TD></TR><TR><TD>
</TD><TD>
format input-format
</TD></TR><TR><TD>
</TD><TD>
has the same effect, as does the script command
TARGET.
</TD></TR><TR><TD>
</TD><TD>
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
</TD></TR><TR><TD>
</TD><TD>
_b input-format
</TD></TR><TR><TD>
</TD><TD>
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.
</TD></TR><TR><TD>
_Bstatic
</TD><TD>
This flag is accepted for command-line compatibility with the SunOS linker, but has
no effect on ld.
</TD></TR><TR><TD>
_c commandfile
</TD><TD>
Directs ld to read link commands from the file
commandfile. These commands will completely override
ld's default link format (rather than adding to it);
commandfile must specify everything necessary to describe the target format.
</TD></TR><TR><TD>
</TD><TD>
You may also include a script of link commands directly in the command line by
bracketing it between { and } characters.
</TD></TR><TR><TD>
_d, _dc, _dp
</TD><TD>
These three OPTIONS are equivalent; multiple forms are supported for compatibility
with other linkers. Use any of them to make ld assign space to common symbols even if
a relocatable output file is specified (_r). The script command
FORCE_COMMON_ALLOCATION has the same effect.
</TD></TR><TR><TD>
-defsym symbol= expression
</TD><TD>
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.
</TD></TR><TR><TD>
-e entry
</TD><TD>
Use entry as the explicit symbol for beginning execution of your program, rather than
the default entry point.
</TD></TR><TR><TD>
_F, -Fformat
</TD><TD>
Some older linkers used this option throughout a compilation toolchain for
specifying object-file format for both input and output object FILES.
ld's mechanisms (the _b or _format OPTIONS for input FILES, the
TARGET command in linker scripts for output FILES, the
GNUTARGET ENVIRONMENT variable) are more flexible, but it accepts (and ignores) the
_F option flag for compatibility with scripts written to call the old linker.
</TD></TR><TR><TD>
_format input_format
</TD><TD>
Synonym for _b
input_format.
</TD></TR><TR><TD>
_g
</TD><TD>
Accepted, but ignored; provided for compatibility with other tools.
</TD></TR><TR><TD>
_G size
</TD><TD>
Set the maximum size of objects to be optimized using the GP register to
size under MIPS ECOFF. Ignored for other object file FORMATS.
</TD></TR><TR><TD>
--help
</TD><TD>
Print a summary of the command-line OPTIONS on the standard output and exit. This
option and --version begin with two hyphens instead of one for compatibility with other
GNU programs. The other OPTIONS start with only one hyphen for compatibility with
other linkers.
</TD></TR><TR><TD>
_i
</TD><TD>
Perform an incremental link (same as option
_r).
</TD></TR></TABLE>
<A NAME="PAGENUM-290"><P>Page 290</P></A>
<TABLE>
<TR><TD>
_lar
</TD><TD>
Add an archive file ar to the list of FILES to link. This option may be used any number
of times. ld will search its path list for occurrences of
lib ar .a for every ar specified.
</TD></TR><TR><TD>
_Lsearchdir
</TD><TD>
This command adds path searchdir
to the list of paths that ld will search for
archive libraries. You may use this option any number of times.
</TD></TR><TR><TD>
</TD><TD>
The default set of paths searched (without being specified with
_L) depends on what 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.
</TD></TR><TR><TD>
_M
</TD><TD>
Print (to the standard output file) a link map—diagnostic in-formation about
where symbols are mapped by ld, and information on global common storage allocation.
</TD></TR><TR><TD>
_Map mapfile
</TD><TD>
Print to the file mapfile a link map—diagnostic information about where symbols
are mapped by ld, and information on global common storage allocation.
</TD></TR><TR><TD>
_m emulation
</TD><TD>
Emulate the emulation linker. You can list the available emulations with the
--verbose option. This option overrides the compiled-in default, which is the system for which
you configured ld.
</TD></TR><TR><TD>
_N
</TD><TD>
Specifies readable and writable text and
data sections. If the output format supports UNIX-style magic numbers, the output is marked as
OMAGIC.
</TD></TR><TR><TD>
</TD><TD>
When you use the _N option, the linker does not page-align the data segment.
</TD><TR><TR><TD>
_n
</TD><TD>
Sets the text segment to be read-only, and
NMAGIC is written if possible.
</TD><TR><TR><TD>
_noinhibit_exec
</TD><TD>
Normally, the linker will not produce an output file if it encounters errors during the
link process. With this flag, you can specify that you wish the output file retained even
after nonfatal errors.
</TD><TR><TR><TD>
_o output output
</TD><TD>
output is a 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 filename.
</TD><TR><TR><TD>
_oformat output_format
</TD><TD>
Specify the binary format for the output object file. You don't usually need to specify
this, as ld is 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. The script command
OUTPUT_FORMAT can also specify the output format,
but this option overrides it.
</TD><TR><TR><TD>
_R filename file
</TD><TD>
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.
</TD><TR><TR><TD>
_relax
</TD><TD>
An option with machine-dependent effects. Currently this option is only supported on
the H8/300.
</TD></TR><TR><TD>
</TD><TD>
On some platforms, use this option to perform global optimizations that become
possible when the linker resolves addressing in your program, such as relaxing address modes
and synthesizing new instructions in the output object file.
</TD></TR><TR><TD>
</TD><TD>
On platforms where this is not supported,
_relax is accepted, but has no effect.
</TD><TR><TR><TD>
_r
</TD><TD>
Generates relocatable output, that is, 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;
_Ur is an alternative.
</TD></TR><TR><TD>
</TD><TD>
This option does the same as _i.
</TD><TR><TR><TD>
_S
</TD><TD>
Omits debugger symbol information (but not all symbols) from the output file.
</TD><TR><TR><TD>
_s
</TD><TD>
Omits all symbol information from the output file.
</TD><TR><TR><TD>
_sort_common
</TD><TD>
Normally, when ld places the global common symbols in the appropriate output sections,
it sorts them by size. First come all the one-byte symbols, then all the two bytes, then all
the four bytes, and then everything else. This is to prevent gaps between symbols due
to alignment constraints. This option disables that sorting.
</TD></TR></TABLE>
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