<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/110231>110231</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang++-19] "error: type constraint differs in template redeclaration"
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

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

<pre>
    I get the following error while compiling on clang-19:

```text
[build] ../../src/core/include/mp-units/framework/quantity_point.h:111:26: error: type constraint differs in template redeclaration
[build]   111 | MP_UNITS_EXPORT template<QuantitySpec auto QS>
[build]       | ^
[build] ../../src/core/include/mp-units/framework/quantity_point_concepts.h:35:26: note: previous template declaration is here
[build]    35 | MP_UNITS_EXPORT template<QuantitySpec auto QS>
[build]       | ^
```

Here are the offending declarations:
- https://github.com/mpusz/mp-units/blob/5f2cb780376592b967869544a0178e09a64ddfda/src/core/include/mp-units/framework/quantity_point.h#L111-L114
- https://github.com/mpusz/mp-units/blob/5f2cb780376592b967869544a0178e09a64ddfda/src/core/include/mp-units/framework/quantity_point_concepts.h#L35-L36

The same code works fine on clang-17, clang-18, gcc-13, and gcc-14.
</pre>
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