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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - Clang should warn when retaining c_str() from temporary string"
href="http://llvm.org/bugs/show_bug.cgi?id=17102">17102</a>
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<th>Summary</th>
<td>Clang should warn when retaining c_str() from temporary string
</td>
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<th>Product</th>
<td>clang
</td>
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<th>Version</th>
<td>trunk
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>All
</td>
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<th>Status</th>
<td>NEW
</td>
</tr>
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<th>Severity</th>
<td>enhancement
</td>
</tr>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>Frontend
</td>
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
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<th>Reporter</th>
<td>Matthew.Arsenault@amd.com
</td>
</tr>
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<th>CC</th>
<td>llvmbugs@cs.uiuc.edu
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<th>Classification</th>
<td>Unclassified
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<p>
<div>
<pre>Many times I have had to fix use after frees caused by people saving the
pointer from a temporary string's c_str(). The lifetime of the string is only
the assignment to foo expression, so any uses after are invalid. It would be
helpful to warn when a temporary string is used this way.
std::string returnsString()
{
return "arstarstarstarstarst";
}
int main()
{
const char* foo = returnsString().c_str();
printf("This is a use after free %s\n", foo);
return 0;
}</pre>
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