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vxworks相关论文

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<DT><CODE>-g</CODE>
<DD>
Ignored.  Provided for compatibility with other tools.

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<DT><CODE>-G<VAR>value</VAR></CODE>
<DD>
<DT><CODE>-G <VAR>value</VAR></CODE>
<DD>
Set the maximum size of objects to be optimized using the GP register to
<VAR>size</VAR> under MIPS ECOFF.  Ignored for other object file formats.

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<DT><CODE>-help</CODE>
<DD>
Print a summary of the command-line options on the standard output and exit.

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<DT><CODE>-i</CODE>
<DD>
Perform an incremental link (same as option <SAMP>`-r'</SAMP>).

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<DT><CODE>-l<VAR>ar</VAR></CODE>
<DD>
Add archive file <VAR>archive</VAR> to the list of files to link.  This 
option may be used any number of times.  <CODE>ld</CODE> will search its
path-list for occurrences of <CODE>lib<VAR>ar</VAR>.a</CODE> for every <VAR>archive</VAR>
specified.

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<DT><CODE>-L<VAR>searchdir</VAR></CODE>
<DD>
<DT><CODE>-L <VAR>searchdir</VAR></CODE>
<DD>
Add path <VAR>searchdir</VAR> to the list of paths that <CODE>ld</CODE> will search
for archive libraries and <CODE>ld</CODE> 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</CODE> options apply to all <CODE>-l</CODE> options, regardless of the
order in which the options appear.

The default set of paths searched (without being specified with
<SAMP>`-L'</SAMP>) depends on which emulation mode <CODE>ld</CODE> is using, and in
some cases also on how it was configured.  See section <A HREF="ld.html#SEC4">Environment Variables</A>.

The paths can also be specified in a link script with the
<CODE>SEARCH_DIR</CODE> command.  Directories specified this way are searched
at the point in which the linker script appears in the command line.

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<DT><CODE>-M</CODE>
<DD>
Print (to the standard output) a link map--diagnostic information about
where symbols are mapped by <CODE>ld</CODE>, and information on global common
storage allocation.

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<DT><CODE>-Map <VAR>mapfile</VAR></CODE>
<DD>
Print to the file <VAR>mapfile</VAR> a link map--diagnostic information
about where symbols are mapped by <CODE>ld</CODE>, and information on global
common storage allocation.

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<DT><CODE>-m<VAR>emulation</VAR></CODE>
<DD>
<DT><CODE>-m <VAR>emulation</VAR></CODE>
<DD>
Emulate the <VAR>emulation</VAR> linker.  You can list the available
emulations with the <SAMP>`--verbose'</SAMP> or <SAMP>`-V'</SAMP> options.  The default
depends on how your <CODE>ld</CODE> was configured.

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<DT><CODE>-N</CODE>
<DD>
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</CODE>.

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<DT><CODE>-n</CODE>
<DD>
Set the text segment to be read only, and mark the output as
<CODE>NMAGIC</CODE> if possible.

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<DT><CODE>-noinhibit-exec</CODE>
<DD>
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.

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<DT><CODE>-no-keep-memory</CODE>
<DD>
<CODE>ld</CODE> normally optimizes for speed over memory usage by caching the
symbol tables of input files in memory.  This option tells <CODE>ld</CODE> to
instead optimize for memory usage, by rereading the symbol tables as
necessary.  This may be required if <CODE>ld</CODE> runs out of memory space
while linking a large executable.

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<DT><CODE>-o <VAR>output</VAR></CODE>
<DD>
Use <VAR>output</VAR> as the name for the program produced by <CODE>ld</CODE>; if this
option is not specified, the name <TT>`a.out'</TT> is used by default.  The
script command <CODE>OUTPUT</CODE> can also specify the output file name.

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<DT><CODE>-oformat <VAR>output-format</VAR></CODE>
<DD>
<CODE>ld</CODE> may be configured to support more than one kind of object
file.  If your <CODE>ld</CODE> is configured this way, you can use the
<SAMP>`-oformat'</SAMP> option to specify the binary format for the output
object file.  Even when <CODE>ld</CODE> is configured to support alternative
object formats, you don't usually need to specify this, as <CODE>ld</CODE>
should be configured to produce as a default output format the most
usual format on each machine.  <VAR>output-format</VAR> is a text string, the
name of a particular format supported by the BFD libraries.  (You can
list the available binary formats with <SAMP>`objdump -i'</SAMP>.)  The script
command <CODE>OUTPUT_FORMAT</CODE> can also specify the output format, but
this option overrides it.  See section <A HREF="ld.html#SEC26">BFD</A>.

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<DT><CODE>-R <VAR>filename</VAR></CODE>
<DD>
Read symbol names and their addresses from <VAR>filename</VAR>, 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.
 
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<DT><CODE>-relax</CODE>
<DD>
An option with machine dependent effects.  
Currently this option is only supported on the H8/300 and the Intel 960.
See section <A HREF="ld.html#SEC25"><CODE>ld</CODE> and the Intel 960 family</A>.

On some platforms, the <SAMP>`-relax'</SAMP> option performs global optimizations that
become possible when the linker resolves addressing in the program, such
as relaxing address modes and synthesizing new instructions in the
output object file.  

On platforms where this is not supported, <SAMP>`-relax'</SAMP> is accepted, but
ignored.

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<DT><CODE>-retain-symbols-file <VAR>filename</VAR></CODE>
<DD>
Retain <EM>only</EM> the symbols listed in the file <VAR>filename</VAR>,
discarding all others.  <VAR>filename</VAR> 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.

<SAMP>`-retain-symbols-file'</SAMP> does <EM>not</EM> discard undefined symbols,
or symbols needed for relocations.

You may only specify <SAMP>`-retain-symbols-file'</SAMP> once in the command
line.  It overrides <SAMP>`-s'</SAMP> and <SAMP>`-S'</SAMP>.

<DT><CODE>-rpath <VAR>dir</VAR></CODE>
<DD>
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Add a directory to the runtime library search path.  This is used when
linking an ELF executable with shared objects.  All <CODE>-rpath</CODE>
arguments are concatenated and passed to the runtime linker, which uses
them to locate shared objects at runtime.  The <CODE>-rpath</CODE> option is
also used when locating shared objects which are needed by shared
objects explicitly included in the link; see the description of the
<CODE>-rpath-link</CODE> option.  If <CODE>-rpath</CODE> is not used when linking an
ELF executable, the contents of the environment variable
<CODE>LD_RUN_PATH</CODE> will be used if it is defined.

The <CODE>-rpath</CODE> option may also be used on SunOS.  By default, on
SunOS, the linker will form a runtime search patch out of all the
<CODE>-L</CODE> options it is given.  If a <CODE>-rpath</CODE> option is used, the
runtime search path will be formed exclusively using the <CODE>-rpath</CODE>
options, ignoring the <CODE>-L</CODE> options.  This can be useful when using
gcc, which adds many <CODE>-L</CODE> options which may be on NFS mounted
filesystems.

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<DT><CODE>-rpath-link <VAR>DIR</VAR></CODE>
<DD>
When using ELF or SunOS, one shared library may require another.  This
happens when an <CODE>ld -shared</CODE> link includes a shared library as one
of the input files.

When the linker encounters such a dependency when doing a non-shared,
non-relocateable 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 <CODE>-rpath-link</CODE> option
specifies the first set of directories to search.  The
<CODE>-rpath-link</CODE> option may specify a sequence of directory names
either by specifying a list of names separated by colons, or by
appearing multiple times.

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

<OL>
<LI>

Any directories specified by <CODE>-rpath-link</CODE> options.
<LI>

Any directories specified by <CODE>-rpath</CODE> options.  The difference
between <CODE>-rpath</CODE> and <CODE>-rpath-link</CODE> is that directories
specified by <CODE>-rpath</CODE> options are included in the executable and
used at runtime, whereas the <CODE>-rpath-link</CODE> option is only effective
at link time.
<LI>

On an ELF system, if the <CODE>-rpath</CODE> and <CODE>rpath-link</CODE> options
were not used, search the contents of the environment variable
<CODE>LD_RUN_PATH</CODE>.
<LI>

On SunOS, if the <CODE>-rpath</CODE> option was not used, search any
directories specified using <CODE>-L</CODE> options.
<LI>

For a native linker, the contents of the environment variable
<CODE>LD_LIBRARY_PATH</CODE>.
<LI>

The default directories, normally <TT>`/lib'</TT> and <TT>`/usr/lib'</TT>.
</OL>

If the required shared library is not found, the linker will issue a
warning and continue with the link.

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<DT><CODE>-r</CODE>
<DD>
Generate relocatable output--i.e., generate an output file that can in
turn serve as input to <CODE>ld</CODE>.  This is often called <EM>partial
linking</EM>.  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</CODE>.
If this option is not specified, an absolute file is produced.  When
linking C++ programs, this option <EM>will not</EM> resolve references to
constructors; to do that, use <SAMP>`-Ur'</SAMP>.

This option does the same thing as <SAMP>`-i'</SAMP>.

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<DT><CODE>-S</CODE>
<DD>
Omit debugger symbol information (but not all symbols) from the output file.

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<DT><CODE>-s</CODE>
<DD>
Omit all symbol information from the output file.

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<DT><CODE>-soname <VAR>name</VAR></CODE>
<DD>
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.

<DT><CODE>-shared</CODE>
<DD>
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Create a shared library.  This is currently only supported on ELF and
SunOS platforms.  On SunOS, the linker will automatically create a
shared library if the <CODE>-e</CODE> option is not used and there are
undefined symbols in the link.

<DT><CODE>-sort-common</CODE>
<DD>
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Normally, when <CODE>ld</CODE> 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.

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<DT><CODE>-split-by-reloc <VAR>count</VAR></CODE>
<DD>
Trys to creates extra sections in the output file so that no single output section
in the file contains more than <VAR>count</VAR> relocations.  This
is useful when generating huge relocatable 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 <VAR>count</VAR> relocations one output section will contain that
many relocations.

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<DT><CODE>-split-by-file</CODE>
<DD>
Similar to -split-by-reloc but creates a new output section for each
input file.

<DT><CODE>-stats</CODE>
<DD>
Compute and display statistics about the operation of the linker,
such as execution time and memory usage.

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<DT><CODE>-Tbss <VAR>org</VAR></CODE>
<DD>
<DT><CODE>-Tdata <VAR>org</VAR></CODE>
<DD>
<DT><CODE>-Ttext <VAR>org</VAR></CODE>
<DD>
Use <VAR>org</VAR> as the starting address for--respectively--the
<CODE>bss</CODE>, <CODE>data</CODE>, or the <CODE>text</CODE> segment of the output file.
<VAR>org</VAR> must be a single hexadecimal integer;
for compatibility with other linkers, you may omit the leading
<SAMP>`0x'</SAMP> usually associated with hexadecimal values.

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<DT><CODE>-T <VAR>commandfile</VAR></CODE>
<DD>
<DT><CODE>-T<VAR>commandfile</VAR></CODE>
<DD>
Read link commands from the file <VAR>commandfile</VAR>.  These commands
replace <CODE>ld</CODE>'s default link script (rather than adding
to it), so <VAR>commandfile</VAR> must specify everything necessary to describe
the target format.  See section <A HREF="ld.html#SEC5">Command Language</A>.  If <VAR>commandfile</VAR> does not
exist, <CODE>ld</CODE> looks for it in the directories specified by any
preceding <SAMP>`-L'</SAMP> options.  Multiple <SAMP>`-T'</SAMP> options accumulate.

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<DT><CODE>-t</CODE>
<DD>
Print the names of the input files as <CODE>ld</CODE> processes them.