1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- This file documents the GNU linker LD 4(GNU Toolchain for the A-profile Architecture 10.3-2021.07 (arm-10.29)) 5version 2.36.1. 6 7Copyright (C) 1991-2021 Free Software Foundation, Inc. 8 9Permission is granted to copy, distribute and/or modify this document 10under the terms of the GNU Free Documentation License, Version 1.3 11or any later version published by the Free Software Foundation; 12with no Invariant Sections, with no Front-Cover Texts, and with no 13Back-Cover Texts. A copy of the license is included in the 14section entitled "GNU Free Documentation License". --> 15<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> 16<head> 17<title>LD: MRI</title> 18 19<meta name="description" content="LD: MRI"> 20<meta name="keywords" content="LD: MRI"> 21<meta name="resource-type" content="document"> 22<meta name="distribution" content="global"> 23<meta name="Generator" content="makeinfo"> 24<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 25<link href="index.html#Top" rel="start" title="Top"> 26<link href="LD-Index.html#LD-Index" rel="index" title="LD Index"> 27<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> 28<link href="index.html#Top" rel="up" title="Top"> 29<link href="GNU-Free-Documentation-License.html#GNU-Free-Documentation-License" rel="next" title="GNU Free Documentation License"> 30<link href="Bug-Reporting.html#Bug-Reporting" rel="previous" title="Bug Reporting"> 31<style type="text/css"> 32<!-- 33a.summary-letter {text-decoration: none} 34blockquote.smallquotation {font-size: smaller} 35div.display {margin-left: 3.2em} 36div.example {margin-left: 3.2em} 37div.indentedblock {margin-left: 3.2em} 38div.lisp {margin-left: 3.2em} 39div.smalldisplay {margin-left: 3.2em} 40div.smallexample {margin-left: 3.2em} 41div.smallindentedblock {margin-left: 3.2em; font-size: smaller} 42div.smalllisp {margin-left: 3.2em} 43kbd {font-style:oblique} 44pre.display {font-family: inherit} 45pre.format {font-family: inherit} 46pre.menu-comment {font-family: serif} 47pre.menu-preformatted {font-family: serif} 48pre.smalldisplay {font-family: inherit; font-size: smaller} 49pre.smallexample {font-size: smaller} 50pre.smallformat {font-family: inherit; font-size: smaller} 51pre.smalllisp {font-size: smaller} 52span.nocodebreak {white-space:nowrap} 53span.nolinebreak {white-space:nowrap} 54span.roman {font-family:serif; font-weight:normal} 55span.sansserif {font-family:sans-serif; font-weight:normal} 56ul.no-bullet {list-style: none} 57--> 58</style> 59 60 61</head> 62 63<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> 64<a name="MRI"></a> 65<div class="header"> 66<p> 67Next: <a href="GNU-Free-Documentation-License.html#GNU-Free-Documentation-License" accesskey="n" rel="next">GNU Free Documentation License</a>, Previous: <a href="Reporting-Bugs.html#Reporting-Bugs" accesskey="p" rel="previous">Reporting Bugs</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p> 68</div> 69<hr> 70<a name="MRI-Compatible-Script-Files"></a> 71<h2 class="appendix">Appendix A MRI Compatible Script Files</h2> 72<a name="index-MRI-compatibility"></a> 73<p>To aid users making the transition to <small>GNU</small> <code>ld</code> from the MRI 74linker, <code>ld</code> can use MRI compatible linker scripts as an 75alternative to the more general-purpose linker scripting language 76described in <a href="Scripts.html#Scripts">Scripts</a>. MRI compatible linker scripts have a much 77simpler command set than the scripting language otherwise used with 78<code>ld</code>. <small>GNU</small> <code>ld</code> supports the most commonly used MRI 79linker commands; these commands are described here. 80</p> 81<p>In general, MRI scripts aren’t of much use with the <code>a.out</code> object 82file format, since it only has three sections and MRI scripts lack some 83features to make use of them. 84</p> 85<p>You can specify a file containing an MRI-compatible script using the 86‘<samp>-c</samp>’ command-line option. 87</p> 88<p>Each command in an MRI-compatible script occupies its own line; each 89command line starts with the keyword that identifies the command (though 90blank lines are also allowed for punctuation). If a line of an 91MRI-compatible script begins with an unrecognized keyword, <code>ld</code> 92issues a warning message, but continues processing the script. 93</p> 94<p>Lines beginning with ‘<samp>*</samp>’ are comments. 95</p> 96<p>You can write these commands using all upper-case letters, or all 97lower case; for example, ‘<samp>chip</samp>’ is the same as ‘<samp>CHIP</samp>’. 98The following list shows only the upper-case form of each command. 99</p> 100<dl compact="compact"> 101<dd><a name="index-ABSOLUTE-_0028MRI_0029"></a> 102</dd> 103<dt><code>ABSOLUTE <var>secname</var></code></dt> 104<dt><code>ABSOLUTE <var>secname</var>, <var>secname</var>, … <var>secname</var></code></dt> 105<dd><p>Normally, <code>ld</code> includes in the output file all sections from all 106the input files. However, in an MRI-compatible script, you can use the 107<code>ABSOLUTE</code> command to restrict the sections that will be present in 108your output program. If the <code>ABSOLUTE</code> command is used at all in a 109script, then only the sections named explicitly in <code>ABSOLUTE</code> 110commands will appear in the linker output. You can still use other 111input sections (whatever you select on the command line, or using 112<code>LOAD</code>) to resolve addresses in the output file. 113</p> 114<a name="index-ALIAS-_0028MRI_0029"></a> 115</dd> 116<dt><code>ALIAS <var>out-secname</var>, <var>in-secname</var></code></dt> 117<dd><p>Use this command to place the data from input section <var>in-secname</var> 118in a section called <var>out-secname</var> in the linker output file. 119</p> 120<p><var>in-secname</var> may be an integer. 121</p> 122<a name="index-ALIGN-_0028MRI_0029"></a> 123</dd> 124<dt><code>ALIGN <var>secname</var> = <var>expression</var></code></dt> 125<dd><p>Align the section called <var>secname</var> to <var>expression</var>. The 126<var>expression</var> should be a power of two. 127</p> 128<a name="index-BASE-_0028MRI_0029"></a> 129</dd> 130<dt><code>BASE <var>expression</var></code></dt> 131<dd><p>Use the value of <var>expression</var> as the lowest address (other than 132absolute addresses) in the output file. 133</p> 134<a name="index-CHIP-_0028MRI_0029"></a> 135</dd> 136<dt><code>CHIP <var>expression</var></code></dt> 137<dt><code>CHIP <var>expression</var>, <var>expression</var></code></dt> 138<dd><p>This command does nothing; it is accepted only for compatibility. 139</p> 140<a name="index-END-_0028MRI_0029"></a> 141</dd> 142<dt><code>END</code></dt> 143<dd><p>This command does nothing whatever; it’s only accepted for compatibility. 144</p> 145<a name="index-FORMAT-_0028MRI_0029"></a> 146</dd> 147<dt><code>FORMAT <var>output-format</var></code></dt> 148<dd><p>Similar to the <code>OUTPUT_FORMAT</code> command in the more general linker 149language, but restricted to S-records, if <var>output-format</var> is ‘<samp>S</samp>’ 150</p> 151<a name="index-LIST-_0028MRI_0029"></a> 152</dd> 153<dt><code>LIST <var>anything</var>…</code></dt> 154<dd><p>Print (to the standard output file) a link map, as produced by the 155<code>ld</code> command-line option ‘<samp>-M</samp>’. 156</p> 157<p>The keyword <code>LIST</code> may be followed by anything on the 158same line, with no change in its effect. 159</p> 160<a name="index-LOAD-_0028MRI_0029"></a> 161</dd> 162<dt><code>LOAD <var>filename</var></code></dt> 163<dt><code>LOAD <var>filename</var>, <var>filename</var>, … <var>filename</var></code></dt> 164<dd><p>Include one or more object file <var>filename</var> in the link; this has the 165same effect as specifying <var>filename</var> directly on the <code>ld</code> 166command line. 167</p> 168<a name="index-NAME-_0028MRI_0029"></a> 169</dd> 170<dt><code>NAME <var>output-name</var></code></dt> 171<dd><p><var>output-name</var> is the name for the program produced by <code>ld</code>; the 172MRI-compatible command <code>NAME</code> is equivalent to the command-line 173option ‘<samp>-o</samp>’ or the general script language command <code>OUTPUT</code>. 174</p> 175<a name="index-ORDER-_0028MRI_0029"></a> 176</dd> 177<dt><code>ORDER <var>secname</var>, <var>secname</var>, … <var>secname</var></code></dt> 178<dt><code>ORDER <var>secname</var> <var>secname</var> <var>secname</var></code></dt> 179<dd><p>Normally, <code>ld</code> orders the sections in its output file in the 180order in which they first appear in the input files. In an MRI-compatible 181script, you can override this ordering with the <code>ORDER</code> command. The 182sections you list with <code>ORDER</code> will appear first in your output 183file, in the order specified. 184</p> 185<a name="index-PUBLIC-_0028MRI_0029"></a> 186</dd> 187<dt><code>PUBLIC <var>name</var>=<var>expression</var></code></dt> 188<dt><code>PUBLIC <var>name</var>,<var>expression</var></code></dt> 189<dt><code>PUBLIC <var>name</var> <var>expression</var></code></dt> 190<dd><p>Supply a value (<var>expression</var>) for external symbol 191<var>name</var> used in the linker input files. 192</p> 193<a name="index-SECT-_0028MRI_0029"></a> 194</dd> 195<dt><code>SECT <var>secname</var>, <var>expression</var></code></dt> 196<dt><code>SECT <var>secname</var>=<var>expression</var></code></dt> 197<dt><code>SECT <var>secname</var> <var>expression</var></code></dt> 198<dd><p>You can use any of these three forms of the <code>SECT</code> command to 199specify the start address (<var>expression</var>) for section <var>secname</var>. 200If you have more than one <code>SECT</code> statement for the same 201<var>secname</var>, only the <em>first</em> sets the start address. 202</p></dd> 203</dl> 204 205<hr> 206<div class="header"> 207<p> 208Next: <a href="GNU-Free-Documentation-License.html#GNU-Free-Documentation-License" accesskey="n" rel="next">GNU Free Documentation License</a>, Previous: <a href="Reporting-Bugs.html#Reporting-Bugs" accesskey="p" rel="previous">Reporting Bugs</a>, Up: <a href="index.html#Top" accesskey="u" rel="up">Top</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="LD-Index.html#LD-Index" title="Index" rel="index">Index</a>]</p> 209</div> 210 211 212 213</body> 214</html> 215