diff --git a/src/query/src/qAggMain.c b/src/query/src/qAggMain.c
index e5f954ec7c24f8d1cec2fd9c7b9c412ec3efb757..6d968a8c510ef88e0b87a61572df8e1e5bd7db70 100644
--- a/src/query/src/qAggMain.c
+++ b/src/query/src/qAggMain.c
@@ -345,7 +345,7 @@ static uint64_t hllCountCnt(uint8_t *buckets) {
     z *= 0.5;
   }
   z += m * hllSigma(buckethisto[0]/(double)m);
-  double E = llroundl(HLL_ALPHA_INF*m*m/z);
+  double E = (double) llroundl(HLL_ALPHA_INF*m*m/z);
 
   return (uint64_t) E;
 }