<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/57057>57057</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Cannot compile with gcc < 8.1
        </td>
    </tr>

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

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

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

<pre>
    The [release notes](https://github.com/llvm/llvm-project/blob/main/llvm/docs/ReleaseNotes.rst#update-on-required-toolchains-to-build-llvm) indicate that gcc >= 7.1 is sufficient to compile LLVM, but I get the following error when I try with 7.2.0:

<pre>llvm-project/llvm/include/llvm/ADT/StringRef.h:85:65: error: call to non-constexpr function 'static std::size_t std::char_traits<char>::length(const char_type*)'
         : Data(Str), Length(Str ? std::char_traits<char>::length(Str) : 0) {}
                                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~</pre>

Constexpr char_traits<>::length was [not implemented until gcc 8.1](https://gcc.gnu.org/onlinedocs/libstdc++/manual/status.html#status.iso.2017). 
</pre>
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