<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/125429>125429</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [maybe missed optimizaton] Suboptimal assembly with constexpr non-static VS static variable
        </td>
    </tr>

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

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

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

<pre>
    Looking at the following example on Godbolt: https://www.godbolt.org/z/cMoojqsd3

the assembly generated is optimal: to call writev one lea and three movs are emitted. If the static specifier is removed from the definition of `vecs` the assembly degenerates into a bunch of `movaps` that copy the `.data` section entries into the stack before passing a pointer to it. 

Given that string literal are supposed to live in static storage and the the Iovecs are just pointers to them whether they are `static` or not probably should not make any difference to the generated asm output.
Notably in the IR output `@__const.main.vecs` switches from `internal` linkage in the optimal "static" case to `private unnamed_addr` in the "non-static" one, which seems both correct _and_ the eventual source of the possibly missed optimization.
</pre>
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