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<base href="https://bugs.llvm.org/">
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Uninitialized value when copying QSharedPointer with structured binding"
href="https://bugs.llvm.org/show_bug.cgi?id=43042">43042</a>
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<th>Summary</th>
<td>Uninitialized value when copying QSharedPointer with structured binding
</td>
</tr>
<tr>
<th>Product</th>
<td>clang
</td>
</tr>
<tr>
<th>Version</th>
<td>unspecified
</td>
</tr>
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<th>Hardware</th>
<td>PC
</td>
</tr>
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<th>OS</th>
<td>All
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Severity</th>
<td>enhancement
</td>
</tr>
<tr>
<th>Priority</th>
<td>P
</td>
</tr>
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<th>Component</th>
<td>Static Analyzer
</td>
</tr>
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<th>Assignee</th>
<td>dcoughlin@apple.com
</td>
</tr>
<tr>
<th>Reporter</th>
<td>jhasse@bixense.com
</td>
</tr>
<tr>
<th>CC</th>
<td>dcoughlin@apple.com, llvm-bugs@lists.llvm.org
</td>
</tr></table>
<p>
<div>
<pre>The following example code:
#include <QSharedPointer>
QPair<int, QSharedPointer<int>> foo() {
return {42, nullptr};
}
int main() {
auto [x, p] = foo();
auto p2 = p;
}
produces the following warning:
QtCore.framework/Headers/qsharedpointer_impl.h:460:7: warning: 1st function
call argument is an uninitialized value [clang-analyzer-core.CallAndMessage]
{ deref(d); }
^
test.cpp:9:12: note: Uninitialized value stored to '.second.d'
auto p2 = p;
^
test.cpp:10:1: note: Calling implicit destructor for 'QPair<int,
QSharedPointer<int>>'
}
^
test.cpp:10:1: note: Calling '~QSharedPointer'
QtCore.framework/Headers/qsharedpointer_impl.h:315:25: note: Calling
'QSharedPointer::deref'
~QSharedPointer() { deref(); }
^
QtCore.framework/Headers/qsharedpointer_impl.h:460:7: note: 1st function call
argument is an uninitialized value
{ deref(d); }
^
Which is weird, since QSharedPointer's copy constructor initializes d. Is this
a false-positive?
See related Qt bug report: <a href="https://bugreports.qt.io/browse/QTBUG-77641">https://bugreports.qt.io/browse/QTBUG-77641</a></pre>
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