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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Static Analyzer false positive: initialized value is believed to be uninitialized"
href="https://bugs.llvm.org/show_bug.cgi?id=39032">39032</a>
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<th>Summary</th>
<td>Static Analyzer false positive: initialized value is believed to be uninitialized
</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>Linux
</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
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<th>Component</th>
<td>Static Analyzer
</td>
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<th>Assignee</th>
<td>dcoughlin@apple.com
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<th>Reporter</th>
<td>bevin.hansson@ericsson.com
</td>
</tr>
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<th>CC</th>
<td>llvm-bugs@lists.llvm.org
</td>
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<pre>Created <span class=""><a href="attachment.cgi?id=20903" name="attach_20903" title="reproducer">attachment 20903</a> <a href="attachment.cgi?id=20903&action=edit" title="reproducer">[details]</a></span>
reproducer
In the attached example, Static Analyzer claims that a value which is
definitely initialized is not. Determining _what_ it is initialized to might be
a more difficult exercise, but it certainly is not uninitialized.
clang -cc1 -analyze -analyzer-checker=core sa.c
sa.c:10:3: warning: 1st function call argument is an uninitialized value
fn(ptr[1]);
^~~~~~~~~~
If we try to access ptr[0] instead, the warning goes away.
I suspect this might be due to deficiencies in RegionStore. SA knows that ptr
points to str, but it cannot seem to locate the binding to str through an
ElementRegion with an offset of 1.
I'd fix this myself, but I don't know if this is a problem with how RegionStore
looks up the bindings, either in getBindingForElement or
getBindingForFieldOrElementCommon, or if it's a problem with how it registers
the binding of str. Or something completely different altogether.</pre>
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