<html>
<head>
<base href="https://bugs.llvm.org/">
</head>
<body><table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Failure to optimize out strlen that isn't used for any other purpose than more strlen calls (which don't have any external effect)"
href="https://bugs.llvm.org/show_bug.cgi?id=47153">47153</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>Failure to optimize out strlen that isn't used for any other purpose than more strlen calls (which don't have any external effect)
</td>
</tr>
<tr>
<th>Product</th>
<td>libraries
</td>
</tr>
<tr>
<th>Version</th>
<td>trunk
</td>
</tr>
<tr>
<th>Hardware</th>
<td>PC
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux
</td>
</tr>
<tr>
<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>enhancement
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
<tr>
<th>Component</th>
<td>Scalar Optimizations
</td>
</tr>
<tr>
<th>Assignee</th>
<td>unassignedbugs@nondot.org
</td>
</tr>
<tr>
<th>Reporter</th>
<td>gabravier@gmail.com
</td>
</tr>
<tr>
<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>void f(const char *a)
{
while (*a)
a += strlen(a);
}
This can be optimized to doing nothing. This transformation is done by GCC, but
not by LLVM. The same transformation can be done if `strlen(a)` is replaced by
`strspn(a, some_other_string)`, and can probably also be done for more examples
alike to this with alike functions.</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are on the CC list for the bug.</li>
</ul>
</body>
</html>