<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=http://email.email.llvm.org/c/eJy9VMFu4yAQ_Rp8QYlsMHFy8CGNm3MPK-1xhWFiUxHjAk63_fod24majVKp0laLBuw3MMO8YaB2-q1UVnbNIhr9RqM3TQM-UEkP0gagvQsmmhPQFjwQviVpRdLLuEpnUX1_1jBuOmUHDZTwnWq96xzhj9dGQzBdQ0PUozO-tSaCx51mNFv8-lvpegTRecIYCiofrv2ZLtKjNB1ha8I255nivIRik0N09DfGU9GM8SvzorqhcRcGN3gFIwm-5WPf4EBfpe-Qx_g7E9KgLCWsuA2WFdQEOnRDAE2JeDiaoBYzXEyWi9EyEFF9d3rolxoRl9Phu_tUOxfHg6cejg7rILYwU_724ywe_7eIL6y5VxNtjP3Ehu1RGqdrZ-PS-QbRO_af8odT-Yt4TnTJ9YZvZIJV2DpfKumtC420J3jvk8Hb8saXie1QL5U7IrD2dPkseu-eQUWEJoQBsLD2gud5nrTlWkCm6tWKHxSIlAlYCc0LWXBWZJofssTKGmwosfow4fXQTJnfYbWyj5s_6kSV_Hs8pmQpY2mGm7N0leXLnGU61zLlslivdS5JngJeWLsc_YxJS3w5ucTIAk5aE2L4mJQhmKYDmMLHCKOJdgJXsYuK7qfX6unyWpmOfnLT6CtSwgoGP2Hp8V5eCjSZuJQTkT_XaXsq>53444</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang-tidy] False Positive in misc-unused-using-decls with user-declared literals
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            bug,
            clang-tidy
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          carlosgalvezp
      </td>
    </tr>
</table>

<pre>
    clang-tidy triggers a false positive here:

```cpp
#include <chrono>

using std::literals::chrono_literals::operator""s;

int main()
{
    auto x = 123s;
}
```
```
source>:3:39: warning: using decl 'operator""s' is unused [misc-unused-using-decls]
using std::literals::chrono_literals::operator""s;
                                      ^
<source>:3:39: note: remove the using
using std::literals::chrono_literals::operator""s;
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
```
https://godbolt.org/z/WaToc4q5j
</pre>
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