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 Assembler "as". 4 5Copyright (C) 1991-2021 Free Software Foundation, Inc. 6 7Permission is granted to copy, distribute and/or modify this document 8under the terms of the GNU Free Documentation License, Version 1.3 9or any later version published by the Free Software Foundation; 10with no Invariant Sections, with no Front-Cover Texts, and with no 11Back-Cover Texts. A copy of the license is included in the 12section entitled "GNU Free Documentation License". 13 --> 14<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> 15<head> 16<title>Using as: a</title> 17 18<meta name="description" content="Using as: a"> 19<meta name="keywords" content="Using as: a"> 20<meta name="resource-type" content="document"> 21<meta name="distribution" content="global"> 22<meta name="Generator" content="makeinfo"> 23<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 24<link href="index.html#Top" rel="start" title="Top"> 25<link href="AS-Index.html#AS-Index" rel="index" title="AS Index"> 26<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> 27<link href="Invoking.html#Invoking" rel="up" title="Invoking"> 28<link href="alternate.html#alternate" rel="next" title="alternate"> 29<link href="Invoking.html#Invoking" rel="previous" title="Invoking"> 30<style type="text/css"> 31<!-- 32a.summary-letter {text-decoration: none} 33blockquote.smallquotation {font-size: smaller} 34div.display {margin-left: 3.2em} 35div.example {margin-left: 3.2em} 36div.indentedblock {margin-left: 3.2em} 37div.lisp {margin-left: 3.2em} 38div.smalldisplay {margin-left: 3.2em} 39div.smallexample {margin-left: 3.2em} 40div.smallindentedblock {margin-left: 3.2em; font-size: smaller} 41div.smalllisp {margin-left: 3.2em} 42kbd {font-style:oblique} 43pre.display {font-family: inherit} 44pre.format {font-family: inherit} 45pre.menu-comment {font-family: serif} 46pre.menu-preformatted {font-family: serif} 47pre.smalldisplay {font-family: inherit; font-size: smaller} 48pre.smallexample {font-size: smaller} 49pre.smallformat {font-family: inherit; font-size: smaller} 50pre.smalllisp {font-size: smaller} 51span.nocodebreak {white-space:nowrap} 52span.nolinebreak {white-space:nowrap} 53span.roman {font-family:serif; font-weight:normal} 54span.sansserif {font-family:sans-serif; font-weight:normal} 55ul.no-bullet {list-style: none} 56--> 57</style> 58 59 60</head> 61 62<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> 63<a name="a"></a> 64<div class="header"> 65<p> 66Next: <a href="alternate.html#alternate" accesskey="n" rel="next">alternate</a>, Up: <a href="Invoking.html#Invoking" accesskey="u" rel="up">Invoking</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p> 67</div> 68<hr> 69<a name="Enable-Listings_003a-_002da_005bcdghlns_005d"></a> 70<h3 class="section">2.1 Enable Listings: <samp>-a[cdghlns]</samp></h3> 71 72<a name="index-_002da"></a> 73<a name="index-_002dac"></a> 74<a name="index-_002dad"></a> 75<a name="index-_002dag"></a> 76<a name="index-_002dah"></a> 77<a name="index-_002dal"></a> 78<a name="index-_002dan"></a> 79<a name="index-_002das"></a> 80<a name="index-listings_002c-enabling"></a> 81<a name="index-assembly-listings_002c-enabling"></a> 82 83<p>These options enable listing output from the assembler. By itself, 84‘<samp>-a</samp>’ requests high-level, assembly, and symbols listing. 85You can use other letters to select specific options for the list: 86‘<samp>-ah</samp>’ requests a high-level language listing, 87‘<samp>-al</samp>’ requests an output-program assembly listing, and 88‘<samp>-as</samp>’ requests a symbol table listing. 89High-level listings require that a compiler debugging option like 90‘<samp>-g</samp>’ be used, and that assembly listings (‘<samp>-al</samp>’) be requested 91also. 92</p> 93<p>Use the ‘<samp>-ag</samp>’ option to print a first section with general assembly 94information, like as version, switches passed, or time stamp. 95</p> 96<p>Use the ‘<samp>-ac</samp>’ option to omit false conditionals from a listing. Any lines 97which are not assembled because of a false <code>.if</code> (or <code>.ifdef</code>, or any 98other conditional), or a true <code>.if</code> followed by an <code>.else</code>, will be 99omitted from the listing. 100</p> 101<p>Use the ‘<samp>-ad</samp>’ option to omit debugging directives from the 102listing. 103</p> 104<p>Once you have specified one of these options, you can further control 105listing output and its appearance using the directives <code>.list</code>, 106<code>.nolist</code>, <code>.psize</code>, <code>.eject</code>, <code>.title</code>, and 107<code>.sbttl</code>. 108The ‘<samp>-an</samp>’ option turns off all forms processing. 109If you do not request listing output with one of the ‘<samp>-a</samp>’ options, the 110listing-control directives have no effect. 111</p> 112<p>The letters after ‘<samp>-a</samp>’ may be combined into one option, 113<em>e.g.</em>, ‘<samp>-aln</samp>’. 114</p> 115<p>Note if the assembler source is coming from the standard input (e.g., 116because it 117is being created by <code>gcc</code> and the ‘<samp>-pipe</samp>’ command-line switch 118is being used) then the listing will not contain any comments or preprocessor 119directives. This is because the listing code buffers input source lines from 120stdin only after they have been preprocessed by the assembler. This reduces 121memory usage and makes the code more efficient. 122</p> 123<hr> 124<div class="header"> 125<p> 126Next: <a href="alternate.html#alternate" accesskey="n" rel="next">alternate</a>, Up: <a href="Invoking.html#Invoking" accesskey="u" rel="up">Invoking</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p> 127</div> 128 129 130 131</body> 132</html> 133