diff --git a/drc/DRCsubcell.c b/drc/DRCsubcell.c
index d328c4b0..73030298 100644
--- a/drc/DRCsubcell.c
+++ b/drc/DRCsubcell.c
@@ -826,6 +826,7 @@ DRCInteractionCheck(def, area, erasebox, func, cdarg)
 		 */
 		subArea = *erasebox;
 		GeoClip(&subArea, &cliparea);
+		if (GEO_RECTNULL(&subArea)) continue;
 		GEO_EXPAND(&subArea, DRCTechHalo, &intArea);
 
 		errorSaveType = DRCErrorType;