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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - Ternary operator: Incorrect value category"
href="https://llvm.org/bugs/show_bug.cgi?id=26448">26448</a>
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<th>Summary</th>
<td>Ternary operator: Incorrect value category
</td>
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<th>Product</th>
<td>clang
</td>
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<th>Version</th>
<td>3.7
</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>
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<th>Severity</th>
<td>normal
</td>
</tr>
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<th>Priority</th>
<td>P
</td>
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<th>Component</th>
<td>C++
</td>
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
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<th>Reporter</th>
<td>roman.perepelitsa@gmail.com
</td>
</tr>
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<th>CC</th>
<td>dgregor@apple.com, llvm-bugs@lists.llvm.org
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<th>Classification</th>
<td>Unclassified
</td>
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<p>
<div>
<pre>The following program unexpectedly triggers the static assertion.
#include <type_traits>
template <class T, class U>
using common = decltype(true ? std::declval<T>() : std::declval<U>());
struct base {};
struct derived : base {};
// common<base, derived> is expected to be base&& (see [expr.cond]/3.2),
// but clang produces base. Hence the assertion fails.
static_assert(std::is_same<common<base, derived>, base&&>(), "");
GCC works correctly on this code snippet.
Note that the following assertion holds (expected behaviour):
static_assert(std::is_same<common<base, base>, base&&>(), "");
Confirmed for clang up to 3.7.1 via gcc.godbolt.org (<a href="http://goo.gl/srkhK5">http://goo.gl/srkhK5</a>).</pre>
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