103 lines
4.5 KiB
HTML
103 lines
4.5 KiB
HTML
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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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<html>
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<!-- This file documents the GNU linker LD
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(Linaro_Binutils-2017.02)
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version 2.27.0.
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Copyright (C) 1991-2016 Free Software Foundation, Inc.
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Permission is granted to copy, distribute and/or modify this document
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under the terms of the GNU Free Documentation License, Version 1.3
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or any later version published by the Free Software Foundation;
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with no Invariant Sections, with no Front-Cover Texts, and with no
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Back-Cover Texts. A copy of the license is included in the
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section entitled "GNU Free Documentation License". -->
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<!-- Created by GNU Texinfo 5.2, http://www.gnu.org/software/texinfo/ -->
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<head>
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<title>LD: Orphan Sections</title>
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<meta name="description" content="LD: Orphan Sections">
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<meta name="keywords" content="LD: Orphan Sections">
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<meta name="resource-type" content="document">
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<meta name="distribution" content="global">
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<meta name="Generator" content="makeinfo">
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<link href="index.html#Top" rel="start" title="Top">
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<link href="LD-Index.html#LD-Index" rel="index" title="LD Index">
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<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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<link href="Expressions.html#Expressions" rel="up" title="Expressions">
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<link href="Location-Counter.html#Location-Counter" rel="next" title="Location Counter">
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<link href="Symbols.html#Symbols" rel="prev" title="Symbols">
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<style type="text/css">
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<!--
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a.summary-letter {text-decoration: none}
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blockquote.smallquotation {font-size: smaller}
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div.display {margin-left: 3.2em}
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div.example {margin-left: 3.2em}
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div.indentedblock {margin-left: 3.2em}
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div.lisp {margin-left: 3.2em}
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div.smalldisplay {margin-left: 3.2em}
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div.smallexample {margin-left: 3.2em}
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div.smallindentedblock {margin-left: 3.2em; font-size: smaller}
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div.smalllisp {margin-left: 3.2em}
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kbd {font-style:oblique}
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pre.display {font-family: inherit}
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pre.format {font-family: inherit}
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pre.menu-comment {font-family: serif}
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pre.menu-preformatted {font-family: serif}
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pre.smalldisplay {font-family: inherit; font-size: smaller}
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pre.smallexample {font-size: smaller}
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pre.smallformat {font-family: inherit; font-size: smaller}
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pre.smalllisp {font-size: smaller}
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span.nocodebreak {white-space:nowrap}
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span.nolinebreak {white-space:nowrap}
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span.roman {font-family:serif; font-weight:normal}
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span.sansserif {font-family:sans-serif; font-weight:normal}
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ul.no-bullet {list-style: none}
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-->
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</style>
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</head>
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<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
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<a name="Orphan-Sections"></a>
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<div class="header">
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<p>
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Next: <a href="Location-Counter.html#Location-Counter" accesskey="n" rel="next">Location Counter</a>, Previous: <a href="Symbols.html#Symbols" accesskey="p" rel="prev">Symbols</a>, Up: <a href="Expressions.html#Expressions" accesskey="u" rel="up">Expressions</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>
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</div>
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<hr>
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<a name="Orphan-Sections-1"></a>
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<h4 class="subsection">3.10.4 Orphan Sections</h4>
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<a name="index-orphan"></a>
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<p>Orphan sections are sections present in the input files which
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are not explicitly placed into the output file by the linker
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script. The linker will still copy these sections into the
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output file, but it has to guess as to where they should be
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placed. The linker uses a simple heuristic to do this. It
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attempts to place orphan sections after non-orphan sections of the
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same attribute, such as code vs data, loadable vs non-loadable, etc.
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If there is not enough room to do this then it places
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at the end of the file.
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</p>
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<p>For ELF targets, the attribute of the section includes section type as
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well as section flag.
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</p>
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<p>The command line options ‘<samp>--orphan-handling</samp>’ and ‘<samp>--unique</samp>’
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(see <a href="Options.html#Options">Command Line Options</a>) can be used to control which
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output sections an orphan is placed in.
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</p>
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<p>If an orphaned section’s name is representable as a C identifier then
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the linker will automatically see <a href="PROVIDE.html#PROVIDE">PROVIDE</a> two symbols:
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__start_SECNAME and __stop_SECNAME, where SECNAME is the name of the
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section. These indicate the start address and end address of the
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orphaned section respectively. Note: most section names are not
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representable as C identifiers because they contain a ‘<samp>.</samp>’
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character.
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</p>
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</body>
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</html>
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