optimize-clips incorrect with clipPath

[xvrh]

I have this icon

<svg xmlns="http://www.w3.org/2000/svg" width="15" height="15" fill="none">
    <defs>
        <clipPath id="a">
            <path fill="#fff" d="M0 0h15v15H0z"/>
        </clipPath>
    </defs>
    <g fill="#374957" clip-path="url(#a)">
        <path d="M11.875 1.25h-.625V.625a.625.625 0 1 0-1.25 0v.625H5V.625a.625.625 0 0 0-1.25 0v.625h-.625A3.129 3.129 0 0 0 0 4.375v7.5A3.129 3.129 0 0 0 3.125 15h8.75A3.129 3.129 0 0 0 15 11.875v-7.5a3.129 3.129 0 0 0-3.125-3.125ZM1.25 4.375A1.875 1.875 0 0 1 3.125 2.5h8.75a1.875 1.875 0 0 1 1.875 1.875V5H1.25v-.625Zm10.625 9.375h-8.75a1.875 1.875 0 0 1-1.875-1.875V6.25h12.5v5.625a1.875 1.875 0 0 1-1.875 1.875Z"/>
        <path d="M7.5 10.313a.937.937 0 1 0 0-1.875.937.937 0 0 0 0 1.874ZM4.375 10.313a.937.937 0 1 0 0-1.875.937.937 0 0 0 0 1.874ZM10.625 10.313a.937.937 0 1 0 0-1.875.937.937 0 0 0 0 1.874Z"/>
    </g>
</svg>

When I compile it with vector_graphics_compiler like this:

dart run vector_graphics_compiler -i assets/calendar.svg -o assets/calendar.vec

If I pass --no-optimize-clips to the compiler, it works correctly.