<p>I've accidentally stumbled on this. In the <code>lsh_search_impl.hpp</code> file, method </p>

<pre><code>void LSHSearch&lt;SortPolicy&gt;::Search()
</code></pre>

<p>there is this OpenMP statement:</p>

<pre><code>  #pragma omp parallel for \
      shared(resultingNeighbors, distances) \
      schedule(dynamic)\
      reduction(+:avgIndicesReturned)
</code></pre>

<p>which is all fine, except that shared variables are not explicitly protected against racing conditions, namely the <code>BaseCase</code> method which actually modifies them, lacks any <code>#pragma atomic</code> or <code>#pragma critical</code> directives (both implementation of this method in the same file).</p>

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