<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/83135>83135</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            "missing default label" when all enum values are covered
        </td>
    </tr>

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

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

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

<pre>
    Hi, I have a code snippet containing `switch` statement that always raises a warning: https://gist.github.com/mkmkme/eeb37b9af0869e00e0a2a45ae3c5aa61

Here in the code `switch` statement covers all possible `enum` values, but when I compile it with
```
clang++-18 -std=c++23 -Wall -Wextra -Weverything llvm-test.cpp
```

I'm getting
```
llvm-test.cpp:21:3: warning: 'switch' missing 'default' label [-Wswitch-default]
   21 |   switch (type) {
      |   ^
1 warning generated.
```

If I add `default` label there, I'll be getting
```
llvm-test.cpp:55:3: warning: default label in switch which covers all enumeration values [-Wcovered-switch-default]
   55 |   default: break;
      |   ^
1 warning generated.
```

I think the first one is false-positive.

My setup:
```
❯ clang-18 -v
Ubuntu clang version 18.1.0 (++20240221023121+bba39443eb91-1~exp1~20240221023233.52)
Target: aarch64-unknown-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
Found candidate GCC installation: /usr/bin/../lib/gcc/aarch64-linux-gnu/11
Selected GCC installation: /usr/bin/../lib/gcc/aarch64-linux-gnu/11
Candidate multilib: .;@m64
Selected multilib: .;@m64
```

(reproduced the same behaviour on x86_64)

Ubuntu 22.04. Clang installed via script from apt.llvm.org
</pre>
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