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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - A invalid partial specialization is accepted"
href="https://bugs.llvm.org/show_bug.cgi?id=51710">51710</a>
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<th>Summary</th>
<td>A invalid partial specialization is accepted
</td>
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<tr>
<th>Product</th>
<td>clang
</td>
</tr>
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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>
</tr>
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>enhancement
</td>
</tr>
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<th>Priority</th>
<td>P
</td>
</tr>
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<th>Component</th>
<td>C++2a
</td>
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
</td>
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<th>Reporter</th>
<td>xmh970252187@gmail.com
</td>
</tr>
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<th>CC</th>
<td>blitzrakete@gmail.com, erik.pilkington@gmail.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
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<p>
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<pre>template<typename T, T ptr>
struct A{
static const int c = 0;
};
template<class T, T** ptr>
struct A<T*,ptr>{.
static const int v = 0;
};
As per [temp.spec.partial.general] p9
<span class="quote">> Within the argument list of a partial specialization, the following restrictions apply:</span >
<span class="quote">>> - The partial specialization shall be more specialized than the primary template ([temp.spec.partial.order]).</span >
`A<T*,ptr>` is not more specialized than the primary template, synthesized a
unique type for the template parameter in partial specialization, A<UniqueT*,
PTR>(where PTR has type UniqueT**) compare with A<T, ptr>
UniqueT* / T => deduce T with UniqueT*
PTR / ptr => deduce T with UniqueT**
as per [temp.deduct.partial] p8 and [temp.deduct.type] p2, the partial
specialization is not more specialized than the primary template.</pre>
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