<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/110808>110808</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            libcxx fails to build with `__cxx03/__algorithm/adjacent_find.h: Header cxx03 is not a valid header`
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            libc++,
            build-problem
      </td>
    </tr>

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

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

<pre>
    On Ubuntu jammy:

```
FAILED: /build/source/build-llvm/include/c++/v1/libcxx.imp
cd /build/source/build-llvm/runtimes/runtimes-bins/libcxx/include && /usr/bin/python3.10 /build/source/libcxx/utils/generate_iwyu_mapping.py -o /build/source/build-llvm/include/c++/v1/libcxx.imp
Traceback (most recent call last):
  File "/build/source/libcxx/utils/generate_iwyu_mapping.py", line 92, in <module>
    main(sys.argv[1:])
  File "/build/source/libcxx/utils/generate_iwyu_mapping.py", line 82, in main
 raise RuntimeError(f"{header}: Header {public} is not a valid header")
RuntimeError: __cxx03/__algorithm/adjacent_find.h: Header cxx03 is not a valid header
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJy0lEmP2yAYhn8NvnyKhcHxcvAhmYzVSpUqVe05wkBiphgslkzy7yucZBapVQ-dSsgCBM_7LS9m3qujkbJD6y1a7zIWw2hd5y_6JH1wMhusuHRfDfwYogkRntg0XRDdILxD-P6t8G0sy37z-cvjDtENINIPUWmBSO9tdFzeN1ZanyZEemW4jiJtc0S2y-hPBSK9VgM_n3M1zVcmF3-HuWiCmqR_M10NyvgX3KsgIFIhUiVm9C6BlEGkny9htIbmBf6t2gslBqUT9iiNdCzIvXq-xP3E5lmZYz5fYGU_MPfvjnE5MP4TEGkm6wM4yaUJwJnWoJkPiLQvLQHolU4Jkn9KYbn_AFoZCe0yVQYQfZisiFoi-nhXA5hYKl7jLz5n7nhC622RolnvUlj_K6bmHtOiflVxTHkJ3669f3TOOkSaQ7pVb0fJhHSoXnz5aVkAqrdzHLTiqN6B8mBsAAYnppWA2_mkeEviHZduYL_n5zOmiPT7PdNH61QYU1-ZeGKpPfuDMiIf3-gt5_8g9P4hZaKjoqUty2RX1KRuqqJaV9nYVYe64A2lgrNqKBrR4kNJy-ZQC9EWa1pmqiOYlAXGBLe0LKq8lHUtK9GUtKhpSwtUYjkxpfNkw9y6Y6a8j7IrCtzgJtNskNovfwNCUmfu3kz1RoRcLTw7O2g5pd31LnNdYq2GePSoxFr54F_pQQUtu2uP4cCU9hAsLBh4VmEEVOGPLWWFs-h0N4Yw-2RE0idPqTDGIec2cW8vcIl6dvZJ8pAeZKpD8t-tFKeO_AoAAP__nMqdkA">