<p>You can see the problem on<br>
<a href="https://cloud.githubusercontent.com/assets/1190866/22409681/cfd638f6-e642-11e6-98a3-5e601d216712.png" target="_blank"><img src="https://cloud.githubusercontent.com/assets/1190866/22409681/cfd638f6-e642-11e6-98a3-5e601d216712.png" alt="image" style="max-width:100%;"></a>. The way goes back over itself.</p>
<p>I don't consider it a bug that it fails to form a polygon, even after <code>buffer(0)</code> from geos. If it were a bug, I'd classify it as wontfix given the likely effort in expanding recovery of broken polygons.</p>
<p>As for why the OSMF servers produce a polygon, it could be anything from a different geos version to a different osm2pgsql version.</p>

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