-.\" Copyright (c) 1991, 1992 Free Software Foundation
+.\" Copyright (c) 1991, 92, 93, 94, 95, 96, 97, 98, 1999 Free Software Foundation
.\" See section COPYING for conditions for redistribution
.TH ld 1 "17 August 1992" "cygnus support" "GNU Development Tools"
.de BP
.I input-format\c
\&\|]
.RB "[\|" \-Bstatic "\|]"
+.RB "[\|" \-Bdynamic "\|]"
+.RB "[\|" \-Bsymbolic "\|]"
.RB "[\|" "\-c\ "\c
.I commandfile\c
\&\|]
+.RB "[\|" \-\-cref "\|]"
.RB "[\|" \-d | \-dc | \-dp\c
\|]
.br
\& = \c
.I expression\c
\&\|]
+.RB "[\|" \-\-demangle "\|]"
+.RB "[\|" \-\-no\-demangle "\|]"
.RB "[\|" "\-e\ "\c
.I entry\c
\&\|]
-.RB "[\|" \-F "\|]"
+.RB "[\|" \-embedded\-relocs "\|]"
+.RB "[\|" \-E "\|]"
+.RB "[\|" \-export\-dynamic "\|]"
+.RB "[\|" "\-f\ "\c
+.I name\c
+\&\|]
+.RB "[\|" "\-\-auxiliary\ "\c
+.I name\c
+\&\|]
.RB "[\|" "\-F\ "\c
-.I format\c
+.I name\c
+\&\|]
+.RB "[\|" "\-\-filter\ "\c
+.I name\c
\&\|]
.RB "[\|" "\-format\ "\c
.I input-format\c
\&\|]
.RB "[\|" \-g "\|]"
-.RB "[\|" \-G\c
+.RB "[\|" \-G
.I size\c
\&\|]
+.RB "[\|" "\-h\ "\c
+.I name\c
+\&\|]
+.RB "[\|" "\-soname\ "\c
+.I name\c
+\&\|]
.RB "[\|" \-\-help "\|]"
.RB "[\|" \-i "\|]"
.RB "[\|" \-l\c
.I searchdir\c
\&\|]
.RB "[\|" \-M "\|]"
-.RB "[\|" \-Map\c
+.RB "[\|" \-Map
.I mapfile\c
\&\|]
-.RB "[\|" \-m\c
+.RB "[\|" \-m
.I emulation\c
\&\|]
.RB "[\|" \-n | \-N "\|]"
.RB "[\|" \-noinhibit-exec "\|]"
+.RB "[\|" \-no\-keep\-memory "\|]"
+.RB "[\|" \-no\-warn\-mismatch "\|]"
+.RB "[\|" \-O\c
+.I level\c
+\&\|]
.RB "[\|" "\-oformat\ "\c
.I output-format\c
\&\|]
\&\|]
.RB "[\|" \-relax "\|]"
.RB "[\|" \-r | \-Ur "\|]"
+.RB "[\|" "\-rpath\ "\c
+.I directory\c
+\&\|]
+.RB "[\|" "\-rpath\-link\ "\c
+.I directory\c
+\&\|]
.RB "[\|" \-S "\|]"
.RB "[\|" \-s "\|]"
+.RB "[\|" \-shared "\|]"
.RB "[\|" \-sort\-common "\|]"
+.RB "[\|" "\-split\-by\-reloc\ "\c
+.I count\c
+\&\|]
+.RB "[\|" \-split\-by\-file "\|]"
.RB "[\|" "\-T\ "\c
.I commandfile\c
\&\|]
\&]
.RB "[\|" \-V "\|]"
.RB "[\|" \-v "\|]"
+.RB "[\|" \-\-verbose "\|]"
.RB "[\|" \-\-version "\|]"
.RB "[\|" \-warn\-common "\|]"
+.RB "[\|" \-warn\-constructors "\|]"
+.RB "[\|" \-warn\-multiple\-gp "\|]"
+.RB "[\|" \-warn\-once "\|]"
+.RB "[\|" \-warn\-section\-align "\|]"
+.RB "[\|" \-\-whole\-archive "\|]"
+.RB "[\|" \-\-no\-whole\-archive "\|]"
+.RB "[\|" "\-\-wrap\ "\c
+.I symbol\c
+\&\|]
.RB "[\|" \-X "\|]"
.RB "[\|" \-x "\|]"
.ad b
option that requires them.
.TP
-.BI "-A" "architecture"\c
-\&
+.BI "-A" "architecture"
In the current release of \c
.B ld\c
\&, this option is useful only for the
\& 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 \c
-.B \-l\c
-\&
+.B \-l
specifies a library.
.TP
-.BI "\-b " "input-format"\c
-\&
+.BI "\-b " "input-format"
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
\c
.TP
.B \-Bstatic
-This flag is accepted for command-line compatibility with the SunOS linker,
-but has no effect on \c
-.B ld\c
-\&.
+Do not link against shared libraries. This is only meaningful on
+platforms for which shared libraries are supported.
+
+.TP
+.B \-Bdynamic
+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.
+
+.TP
+.B \-Bsymbolic
+When creating a shared library, bind references to global symbols to
+the definition within the shared library, if any. Normally, it is
+possible for a program linked against a shared library to override the
+definition within the shared library. This option is only meaningful
+on ELF platforms which support shared libraries.
.TP
-.BI "\-c " "commandfile"\c
-\&
+.BI "\-c " "commandfile"
Directs \c
.B ld\c
\& to read link commands from the file
.B }\c
\|' characters.
+.TP
+.B \-\-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.
+
.TP
.B \-d
.TP
.B \-dp
These three options are equivalent; multiple forms are supported for
compatibility with other linkers. Use any of them to make \c
-.B ld\c
-\&
+.B ld
assign space to common symbols even if a relocatable output file is
specified (\c
.B \-r\c
\& has the same effect.
.TP
-.BI "-defsym " "symbol"\c
-\& = \c
-.I expression\c
-\&
+.BI "-defsym " "symbol" "\fR = \fP" expression
Create a global symbol in the output file, containing the absolute
address given by \c
.I expression\c
constants or symbols. If you need more elaborate expressions, consider
using the linker command language from a script.
+.TP
+.B \-\-demangle
+.TP
+.B \-\-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. The linker will
+demangle by default unless the environment variable
+.B COLLECT_NO_DEMANGLE
+is set. These options may be used to override the default.
+
.TP
.BI "-e " "entry"\c
\&
Use \c
.I entry\c
\& as the explicit symbol for beginning execution of your
-program, rather than the default entry point. for a
+program, rather than the default entry point. See the `\|\c
+.B ld\c
+\|' entry in `\|\c
+.B info\c
+\|' for a
discussion of defaults and other ways of specifying the
entry point.
.TP
-.B \-F
+.B \-embedded\-relocs
+This option is only meaningful when linking MIPS embedded PIC code,
+generated by the
+.B \-membedded\-pic
+option to the GNU compiler and assembler. It causes the linker to
+create a table which may be used at runtime to relocate any data which
+was statically initialized to pointer values. See the code in
+testsuite/ld-empic for details.
+
.TP
-.BI "-F" "format"\c
-\&
-Some older linkers used this option throughout a compilation toolchain
-for specifying object-file format for both input and output object
-files. \c
-.B ld\c
-\&'s mechanisms (the \c
-.B \-b\c
-\& or \c
-.B \-format\c
-\& options
-for input files, the \c
-.B TARGET\c
-\& command in linker scripts for output
-files, the \c
-.B GNUTARGET\c
-\& environment variable) are more flexible, but
-but it accepts (and ignores) the \c
-.B \-F\c
-\& option flag for compatibility
-with scripts written to call the old linker.
+.B \-E
+.TP
+.B \-export\-dynamic
+When creating an ELF file, add all symbols to the dynamic symbol table.
+Normally, the dynamic symbol table contains only symbols which are used
+by a dynamic object. This option is needed for some uses of
+.I dlopen.
+
+.TP
+.BI "-f " "name"
+.TP
+.BI "--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
+.I name.
.TP
-.BI "\-format " "input\-format"\c
-\&
+.BI "-F " "name"
+.TP
+.BI "--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 should be used as a filter on the symbol table of
+the shared object
+.I name.
+
+.TP
+.BI "\-format " "input\-format"
Synonym for \c
.B \-b\c
\& \c
.I size
under MIPS ECOFF. Ignored for other object file formats.
+.TP
+.BI "-h " "name"
+.TP
+.BI "-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.
+
.TP
.B \-\-help
Print a summary of the command-line options on the standard output and exit.
.I ar\c
\&.a\c
\& for every \c
-.I ar\c
-\&
+.I ar
specified.
.TP
-.BI "\-L" "searchdir"\c
-\&
+.BI "\-L" "searchdir"
This command adds path \c
.I searchdir\c
\& to the list of paths that
\& is using, and in
some cases also on how it was configured. The
paths can also be specified in a link script with the \c
-.B SEARCH_DIR\c
-\&
+.B SEARCH_DIR
command.
.TP
Emulate the
.I emulation
linker. You can list the available emulations with the
+.I \-\-verbose
+or
.I \-V
-option. This option overrides the compiled-in default, which is the
+options. This option overrides the compiled-in default, which is the
system for which you configured
.BR ld .
you wish the output file retained even after non-fatal errors.
.TP
-.BI "\-o " "output"\c
-\&
-.I output\c
-\&
-\c
+.B \-no\-keep\-memory
+The linker normally optimizes for speed over memory usage by caching
+the symbol tables of input files in memory. This option tells the
+linker to instead optimize for memory usage, by rereading the symbol
+tables as necessary. This may be required if the linker runs out of
+memory space while linking a large executable.
+
+.TP
+.B \-no\-warn\-mismatch
+Normally the linker 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 the linker 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.
+
+.TP
+.BI "\-o " "output"
.I output\c
\& is a name for the program produced by \c
.B ld\c
\& can also specify the output file name.
.TP
-.BI "\-oformat " "output\-format"\c
-\&
+.BI "\-O" "level"
+Generate optimized output files. This might use significantly more
+time and therefore probably should be enabled only for generating the
+final binary.
+\c
+.I level\c
+\& is supposed to be a numeric value. Any value greater than zero enables
+the optimizations.
+
+.TP
+.BI "\-oformat " "output\-format"
Specify the binary format for the output object file.
You don't usually need to specify this, as
\c
can also specify the output format, but this option overrides it.
.TP
-.BI "\-R " "filename"\c
-\&
-.I file\c
-\&
+.BI "\-R " "filename"
Read symbol names and their addresses from \c
.I filename\c
\&, but do not
.B \-i\c
\&.
+.TP
+.B \-rpath\ \fIdirectory
+Add a directory to the runtime library search path. This is used when
+linking an ELF executable with shared objects. All
+.B \-rpath
+arguments are concatenated and passed to the runtime linker, which uses
+them to locate shared objects at runtime. The
+.B \-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
+.B \-rpath\-link
+option. If
+.B \-rpath
+is not used when linking an ELF executable, the contents of the
+environment variable
+.B LD_RUN_PATH
+will be used if it is defined.
+
+The
+.B \-rpath
+option may also be used on SunOS. By default, on SunOS, the linker
+will form a runtime search path out of all the
+.B \-L
+options it is given. If a
+.B \-rpath
+option is used, the runtime search path will be formed exclusively
+using the
+.B \-rpath
+options, ignoring
+the
+.B \-L
+options. This can be useful when using gcc, which adds many
+.B \-L
+options which may be on NFS mounted filesystems.
+
+.TP
+.B \-rpath\-link\ \fIdirectory
+When using ELF or SunOS, one shared library may require another. This
+happens when an
+.B 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-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
+.B \-rpath\-link
+option specifies the first set of directories to search. The
+.B \-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.
+
+If the required shared library is not found, the linker will issue a
+warning and continue with the link.
+
.TP
.B \-S
Omits debugger symbol information (but not all symbols) from the output file.
.B \-s
Omits all symbol information from the output file.
+.TP
+.B \-shared
+Create a shared library. This is currently only supported on ELF and
+SunOS platforms (on SunOS it is not required, as the linker will
+automatically create a shared library when there are undefined symbols
+and the
+.B \-e
+option is not used).
+
.TP
.B \-sort\-common
Normally, when
This is to prevent gaps between symbols due to
alignment constraints. This option disables that sorting.
+.TP
+.B \-split\-by\-reloc\ \fIcount
+Trys to creates extra sections in the output file so that no single
+output section in the file contains more than
+.I count
+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
+.I count
+relocations one output section will contain that many relocations.
+
+.TP
+.B \-split\-by\-file
+Similar to
+.B \-split\-by\-reloc
+but creates a new output section for each input file.
+
.TP
.BI "\-Tbss " "org"\c
.TP
.B text\c
\& segment of the output file.
\c
-.I textorg\c
+.I org\c
\& must be a hexadecimal integer.
.TP
-.BI "\-T " "commandfile"\c
-\&
-.TP
-.BI "\-T" "commandfile"\c
+.BI "\-T " "commandfile"
Equivalent to \c
.B \-c \c
.I commandfile\c
turn serve as input to \c
.B ld\c
\&. When linking C++ programs, \c
-.B \-Ur\c
-\&
-\c
+.B \-Ur
.I will\c
\& resolve references to constructors, unlike \c
.B \-r\c
\&.
.TP
-.B \-V
+.B \-\-verbose
Display the version number for \c
.B ld
and list the supported emulations.
Display which input files can and can not be opened.
.TP
-.B \-v
+.B \-v, \-V
Display the version number for \c
.B ld\c
\&.
+The
+.B \-V
+option also lists the supported emulations.
.TP
.B \-\-version
but linkers on some other operating systems do not. This option allows
you to find potential problems from combining global symbols.
+.TP
+.B \-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.
+
+.TP
+.B \-warn\-multiple\-gp
+Warn if the output file requires multiple global-pointer values. This
+option is only meaningful for certain processors, such as the Alpha.
+
+.TP
+.B \-warn\-once
+Only warn once for each undefined symbol, rather than once per module
+which refers to it.
+
+.TP
+.B \-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.
+
+.TP
+.B \-\-whole\-archive
+For each archive mentioned on the command line after the
+.B \-\-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.
+
+.TP
+.B \-\-no\-whole\-archive
+Turn off the effect of the
+.B \-\-whole\-archive
+option for archives which appear later on the command line.
+
+.TP
+.BI "--wrap " "symbol"
+Use a wrapper function for
+.I symbol.
+Any undefined reference to
+.I symbol
+will be resolved to
+.BI "__wrap_" "symbol".
+Any undefined reference to
+.BI "__real_" "symbol"
+will be resolved to
+.I symbol.
+
.TP
.B \-X
-If \c
-.B \-s\c
-\& or \c
-.B \-S\c
-\& is also specified, delete only local symbols
-beginning with `\|\c
+Delete all temporary local symbols. For most targets, this is all local
+symbols whose names begin with `\|\c
.B L\c
\|'.
.TP
.B \-x
-If \c
-.B \-s\c
-\& or \c
-.B \-S\c
-\& is also specified, delete all local symbols,
-not just those beginning with `\|\c
-.B L\c
-\|'.
+Delete all local symbols.
.PP
, Roland H. Pesch.
.SH COPYING
-Copyright (c) 1991, 1992 Free Software Foundation, Inc.
+Copyright (c) 1991, 92, 93, 94, 95, 96, 97, 1998 Free Software Foundation, Inc.
.PP
Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice