1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>snd_BUG_ON()</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Writing an ALSA Driver"><link rel="up" href="useful-functions.html" title="Chapter&#160;16.&#160;Useful Functions"><link rel="prev" href="useful-functions-snd-bug.html" title="snd_BUG()"><link rel="next" href="acknowledgments.html" title="Chapter&#160;17.&#160;Acknowledgments"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><code class="function">snd_BUG_ON()</code></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="useful-functions-snd-bug.html">Prev</a>&#160;</td><th width="60%" align="center">Chapter&#160;16.&#160;Useful Functions</th><td width="20%" align="right">&#160;<a accesskey="n" href="acknowledgments.html">Next</a></td></tr></table><hr></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="useful-functions-snd-bug-on"></a><code class="function">snd_BUG_ON()</code></h2></div></div></div><p>
2        <code class="function">snd_BUG_ON()</code> macro is similar with
3	<code class="function">WARN_ON()</code> macro. For example,  
4
5        </p><div class="informalexample"><pre class="programlisting">
6
7  snd_BUG_ON(!pointer);
8
9          </pre></div><p>
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11	or it can be used as the condition,
12        </p><div class="informalexample"><pre class="programlisting">
13
14  if (snd_BUG_ON(non_zero_is_bug))
15          return -EINVAL;
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17          </pre></div><p>
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19      </p><p>
20        The macro takes an conditional expression to evaluate.
21	When <code class="constant">CONFIG_SND_DEBUG</code>, is set, if the
22	expression is non-zero, it shows the warning message such as
23	<code class="computeroutput">BUG? (xxx)</code>
24	normally followed by stack trace.
25
26	In both cases it returns the evaluated value.
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