<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=http://email.email.llvm.org/c/eJylVE1v4yAQ_TX4MkrkQD4PPvRjq-65q14jbE9iWmwsBifNv98BN2lSVdrDIuIAA2_emxkoXX0qfkOJ1uABgUIt1B33ynVvQ1cF4zowBDT0vSOsITio0RveuvOuBdchuB2EBiFg21sdEHrtdYsBPYGQa5OsHkHHX3cSciPkA5ADE3jDMh_9HbQdkGdAjRtsDY1mFwn21CcX__L0HYim8OyOrMlHdyaAde6dwJr3EdeashLynjsYhsMWu6CT3KOxFrQ96hPdaEUThURPwQ-4jcQiYZeWdtrSZW0q8keR343fZxYv5IpYPOCHjr6YgA5QubY3Fokdhiby4eCfKZVDgJ029sv4abmBjqLHPk6lMl1lhxpBqIfIZRu85jAL9ev6GDH_KsAriNX9uALcXI9eB1ZTOmc5cZyo2w2xeQyD7yCpFerKKFaPny54cDbcuHu5RaMY7YqD0FHAj94znTF1l8M_AMUjW02EPkSGV2CfZWtoS1wS2wMH4JZ5cgSvsRgSX_nEPcZpMpnAn4Zr3KQqGvelGHByTXcV-1vAGiub8i3XP90aRn6Jcb8qSq78r3hdUsKrF5nnfGZ1oeqN2uhMD6FxvtBvk9ZUjUabDd4WTQg9ReikYs8lMpRTrieeWHs4_016796w4lA9GaIBiQcLNVMqawpdr2SOuVrls8V8Xqu1nu02S7Vay_VS55XKrOY3gQqxYOWywyMkCB6LxWP2_wxMIXMp8xm35VwqNZ3PcVltNFabZbneLVDMc2z5BkwjztT5feaLBFkOe2KjNRToy8hFYfYdYiLMDIMJFosfn7OUDH5g-G551-3TC5MlekXi9hctOo00>53133</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            std::conjunction value has wrong type
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          aj-michael
      </td>
    </tr>
</table>

<pre>
    I believe std::conjunction is supposed to derive from one of the template parameters (if there are any), so its `::value` should have the type of one of the template parameters `::value`s. However, it looks like the libc++ implementation will always derive from either `true_type` or `false_type`.

Here's an example that compiles with libstdc++ but fails with libc++.

```
#include <type_traits>

struct V {
    operator bool() {
        return false;
    }
};

struct S {
    static constexpr V value;
};

static_assert(
    std::is_same_v<
        const V,     // <--- This is `const bool` in libc++
        decltype(std::conjunction<S>::value)
    >
);
```
</pre>
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