<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/78111>78111</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            `-DLLVM_ENABLE_LTO=Yes` has the wrong default
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            cmake
      </td>
    </tr>

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

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

<pre>
    `-DLLVM_ENABLE_LTO=Yes` appears to be synonymous with `-DLLVM_ENABLE_LTO=Full` for Clang, leading to extremely long (and undesirable) build times when accidentally configured.

`-DLLVM_ENABLE_LTO=Yes` should either be an error (i.e. force an explicit `Thin` or `Full`), or do work to identify the ideal option on behalf of the user (e.g. `-flto=thin` for Clang, `-flto=auto` for GCC when available).
</pre>
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