<html lang="en">
<head>
<title>GNU Object Attributes - Using as</title>
<meta http-equiv="Content-Type" content="text/html">
<meta name="description" content="Using as">
<meta name="generator" content="makeinfo 4.7">
<link title="Top" rel="start" href="index.html#Top">
<link rel="up" href="Object-Attributes.html#Object-Attributes" title="Object Attributes">
<link rel="next" href="Defining-New-Object-Attributes.html#Defining-New-Object-Attributes" title="Defining New Object Attributes">
<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
<!--
This file documents the GNU Assembler "as".
Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002,
2006, 2007 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 1.1
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''.
man end-->
<meta http-equiv="Content-Style-Type" content="text/css">
<style type="text/css"><!--
pre.display { font-family:inherit }
pre.format { font-family:inherit }
pre.smalldisplay { font-family:inherit; font-size:smaller }
pre.smallformat { font-family:inherit; font-size:smaller }
pre.smallexample { font-size:smaller }
pre.smalllisp { font-size:smaller }
span.sc { font-variant:small-caps }
span.roman { font-family: serif; font-weight: normal; }
--></style>
</head>
<body>
<div class="node">
<p>
<a name="GNU-Object-Attributes"></a>Next: <a rel="next" accesskey="n" href="Defining-New-Object-Attributes.html#Defining-New-Object-Attributes">Defining New Object Attributes</a>,
Up: <a rel="up" accesskey="u" href="Object-Attributes.html#Object-Attributes">Object Attributes</a>
<hr><br>
</div>
<h3 class="section">8.1 <span class="sc">gnu</span> Object Attributes</h3>
<p>The <code>.gnu_attribute</code> directive records an object attribute
with vendor <span class="samp">gnu</span>.
<p>Except for <span class="samp">Tag_compatibility</span>, which has both an integer and a string for
its value, <span class="sc">gnu</span> attributes have a string value if the tag number is odd and
an integer value if the tag number is even. The second bit (<var>tag</var><code> &
2</code> is set for architecture-independent attributes and clear for
architecture-dependent ones.
<h4 class="subsection">8.1.1 Common <span class="sc">gnu</span> attributes</h4>
<p>These attributes are valid on all architectures.
<dl>
<dt><span class="roman">Tag_compatibility (32)</span><dd>The compatibility attribute takes an integer flag value and a vendor name. If
the flag value is 0, the file is compatible with other toolchains. If it is 1,
then the file is only compatible with the named toolchain. If it is greater
than 1, the file can only be processed by other toolchains under some private
arrangement indicated by the flag value and the vendor name.
</dl>
<h4 class="subsection">8.1.2 MIPS Attributes</h4>
<dl>
<dt><span class="roman">Tag_GNU_MIPS_ABI_FP (4)</span><dd>The floating-point ABI used by this object file. The value will be:
<ul>
<li>0 for files not affected by the floating-point ABI.
<li>1 for files using the hardware floating-point with a standard double-precision
FPU.
<li>2 for files using the hardware floating-point ABI with a single-precision FPU.
<li>3 for files using the software floating-point ABI.
<li>4 for files using the hardware floating-point ABI with 64-bit wide
double-precision floating-point registers and 32-bit wide general
purpose registers.
</ul>
</dl>
<h4 class="subsection">8.1.3 PowerPC Attributes</h4>
<dl>
<dt><span class="roman">Tag_GNU_Power_ABI_FP (4)</span><dd>The floating-point ABI used by this object file. The value will be:
<ul>
<li>0 for files not affected by the floating-point ABI.
<li>1 for files using double-precision hardware floating-point ABI.
<li>2 for files using the software floating-point ABI.
<li>3 for files using single-precision hardware floating-point ABI.
</ul>
<br><dt><span class="roman">Tag_GNU_Power_ABI_Vector (8)</span><dd>The vector ABI used by this object file. The value will be:
<ul>
<li>0 for files not affected by the vector ABI.
<li>1 for files using general purpose registers to pass vectors.
<li>2 for files using AltiVec registers to pass vectors.
<li>3 for files using SPE registers to pass vectors.
</ul>
</dl>
</body></html>