visus
/
toolchain-gcc-arm-embedded


			
							<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- This file documents the GNU linker LD
(GNU Arm Embedded Toolchain 10-2020-q4-major)
version 2.35.1.

Copyright (C) 1991-2020 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3
or any later version published by the Free Software Foundation;
with no Invariant Sections, with no Front-Cover Texts, and with no
Back-Cover Texts.  A copy of the license is included in the
section entitled "GNU Free Documentation License". -->
<!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ -->
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Nios II (LD)</title>

<meta name="description" content="Nios II (LD)">
<meta name="keywords" content="Nios II (LD)">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="makeinfo">
<link href="index.html#Top" rel="start" title="Top">
<link href="LD-Index.html#LD-Index" rel="index" title="LD Index">
<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
<link href="Machine-Dependent.html#Machine-Dependent" rel="up" title="Machine Dependent">
<link href="PowerPC-ELF32.html#PowerPC-ELF32" rel="next" title="PowerPC ELF32">
<link href="NDS32.html#NDS32" rel="prev" title="NDS32">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
blockquote.indentedblock {margin-right: 0em}
blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
blockquote.smallquotation {font-size: smaller}
div.display {margin-left: 3.2em}
div.example {margin-left: 3.2em}
div.lisp {margin-left: 3.2em}
div.smalldisplay {margin-left: 3.2em}
div.smallexample {margin-left: 3.2em}
div.smalllisp {margin-left: 3.2em}
kbd {font-style: oblique}
pre.display {font-family: inherit}
pre.format {font-family: inherit}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
pre.smalldisplay {font-family: inherit; font-size: smaller}
pre.smallexample {font-size: smaller}
pre.smallformat {font-family: inherit; font-size: smaller}
pre.smalllisp {font-size: smaller}
span.nolinebreak {white-space: nowrap}
span.roman {font-family: initial; font-weight: normal}
span.sansserif {font-family: sans-serif; font-weight: normal}
ul.no-bullet {list-style: none}
-->
</style>


</head>

<body lang="en">
<a name="Nios-II"></a>
<div class="header">
<p>
Next: <a href="PowerPC-ELF32.html#PowerPC-ELF32" accesskey="n" rel="next">PowerPC ELF32</a>, Previous: <a href="NDS32.html#NDS32" accesskey="p" rel="prev">NDS32</a>, Up: <a href="Machine-Dependent.html#Machine-Dependent" accesskey="u" rel="up">Machine Dependent</a> &nbsp; [<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>
</div>
<hr>
<a name="ld-and-the-Altera-Nios-II"></a>
<h3 class="section">4.10 <code>ld</code> and the Altera Nios II</h3>
<a name="index-Nios-II-call-relaxation"></a>
<a name="index-_002d_002drelax-on-Nios-II"></a>

<p>Call and immediate jump instructions on Nios II processors are limited to
transferring control to addresses in the same 256MB memory segment,
which may result in <code>ld</code> giving
&lsquo;<samp>relocation truncated to fit</samp>&rsquo; errors with very large programs.
The command-line option <samp>--relax</samp> enables the generation of
trampolines that can access the entire 32-bit address space for calls
outside the normal <code>call</code> and <code>jmpi</code> address range.  These
trampolines are inserted at section boundaries, so may not themselves
be reachable if an input section and its associated call trampolines are
larger than 256MB.
</p>
<p>The <samp>--relax</samp> option is enabled by default unless <samp>-r</samp>
is also specified.  You can disable trampoline generation by using the
<samp>--no-relax</samp> linker option.  You can also disable this optimization
locally by using the &lsquo;<samp>set .noat</samp>&rsquo; directive in assembly-language
source files, as the linker-inserted trampolines use the <code>at</code>
register as a temporary.
</p>
<p>Note that the linker <samp>--relax</samp> option is independent of assembler
relaxation options, and that using the GNU assembler&rsquo;s <samp>-relax-all</samp>
option interferes with the linker&rsquo;s more selective call instruction relaxation.
</p>


</body>
</html>