From f4408e8c3ead478db40478041fc9a0c6e3b2a321 Mon Sep 17 00:00:00 2001
From: Nick Lewycky <nicholas@mxc.ca>
Date: Sat, 31 May 2008 23:54:55 +0000
Subject: [PATCH] Add a standard for control-flow unreachable assertions in
 functions that return values, so as to avoid warnings on some platforms.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51831 91177308-0d34-0410-b5e6-96231b3b80d8
---
 docs/CodingStandards.html | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/docs/CodingStandards.html b/docs/CodingStandards.html
index 3a7f8b3d1e9..a99e46e5b58 100644
--- a/docs/CodingStandards.html
+++ b/docs/CodingStandards.html
@@ -623,6 +623,29 @@ assert(isa&lt;PHINode&gt;(Succ-&gt;front()) &amp;&amp; "Only works on PHId BBs!"
 
 <p>You get the idea...</p>
 
+<p>Please be aware when adding assert statements that not all compilers are aware of
+the semantics of the assert.  In some places, asserts are used to indicate a piece of
+code that should not be reached.  These are typically of the form:</p>
+
+<div class="doc_code">
+<pre>
+assert(0 && "Some helpful error message");
+</pre>
+</div>
+
+<p>When used in a function that returns a value, they should be followed with a return
+statement and a comment indicating that this line is never reached.  This will prevent
+a compiler which is unable to deduce that the assert statement never returns from
+generating a warning.</p>
+
+<div class="doc_code">
+<pre>
+assert(0 && "Some helpful error message");
+// Not reached
+return 0;
+</pre>
+</div>
+
 </div>
 
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