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. 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The 76linker treats common symbols as though they are in an input section 77named ‘<samp>COMMON</samp>’. 78</p> 79<p>You may use file names with the ‘<samp>COMMON</samp>’ section just as with any 80other input sections. You can use this to place common symbols from a 81particular input file in one section while common symbols from other 82input files are placed in another section. 83</p> 84<p>In most cases, common symbols in input files will be placed in the 85‘<samp>.bss</samp>’ section in the output file. For example: 86</p><div class="smallexample"> 87<pre class="smallexample">.bss { *(.bss) *(COMMON) } 88</pre></div> 89 90<a name="index-scommon-section"></a> 91<a name="index-small-common-symbols"></a> 92<p>Some object file formats have more than one type of common symbol. For 93example, the MIPS ELF object file format distinguishes standard common 94symbols and small common symbols. In this case, the linker will use a 95different special section name for other types of common symbols. In 96the case of MIPS ELF, the linker uses ‘<samp>COMMON</samp>’ for standard common 97symbols and ‘<samp>.scommon</samp>’ for small common symbols. This permits you 98to map the different types of common symbols into memory at different 99locations. 100</p> 101<a name="index-_005bCOMMON_005d"></a> 102<p>You will sometimes see ‘<samp>[COMMON]</samp>’ in old linker scripts. This 103notation is now considered obsolete. It is equivalent to 104‘<samp>*(COMMON)</samp>’. 105</p> 106 107 108 109</body> 110</html> 111