ld
from the MRI
linker, ld
can use MRI compatible linker scripts as an
alternative to the more general-purpose linker scripting language
described in section Command Language. MRI compatible linker
scripts have a much simpler command set than the scripting language
otherwise used with ld
. GNU ld
supports the most
commonly used MRI linker commands; these commands are described here.
In general, MRI scripts aren't of much use with the a.out
object
file format, since it only has three sections and MRI scripts lack some
features to make use of them.
You can specify a file containing an MRI-compatible script using the `-c' command-line option.
Each command in an MRI-compatible script occupies its own line; each
command line starts with the keyword that identifies the command (though
blank lines are also allowed for punctuation). If a line of an
MRI-compatible script begins with an unrecognized keyword, ld
issues a warning message, but continues processing the script.
Lines beginning with `*' are comments.
You can write these commands using all upper-case letters, or all lower case; for example, `chip' is the same as `CHIP'. The following list shows only the upper-case form of each command.
ABSOLUTE secname
ABSOLUTE secname, secname, ... secname
ld
includes in the output file all sections from all
the input files. However, in an MRI-compatible script, you can use the
ABSOLUTE
command to restrict the sections that will be present in
your output program. If the ABSOLUTE
command is used at all in a
script, then only the sections named explicitly in ABSOLUTE
commands will appear in the linker output. You can still use other
input sections (whatever you select on the command line, or using
LOAD
) to resolve addresses in the output file.
ALIAS out-secname, in-secname
CHIP expression
CHIP expression, expression
END
FORMAT output-format
OUTPUT_FORMAT
command in the more general linker
language, but restricted to one of these output formats:
LIST anything...
ld
command-line option `-M'.
The keyword LIST
may be followed by anything on the
same line, with no change in its effect.
LOAD filename
LOAD filename, filename, ... filename
ld
command line.
NAME output-name
ld
; the
MRI-compatible command NAME
is equivalent to the command-line
option `-o' or the general script language command OUTPUT
.
ORDER secname, secname, ... secname
ORDER secname secname secname
ld
orders the sections in its output file in the
order in which they first appear in the input files. In an MRI-compatible
script, you can override this ordering with the ORDER
command. The
sections you list with ORDER
will appear first in your output
file, in the order specified.
PUBLIC name=expression
PUBLIC name,expression
PUBLIC name expression
SECT secname, expression
SECT secname=expression
SECT secname expression
SECT
command to
specify the start address (expression) for section secname.
If you have more than one SECT
statement for the same
secname, only the first sets the start address.