diff --git a/poly2tri/sweep/sweep.cc b/poly2tri/sweep/sweep.cc
index 778d4f0..1f51fee 100644
--- a/poly2tri/sweep/sweep.cc
+++ b/poly2tri/sweep/sweep.cc
@@ -123,8 +123,7 @@ void Sweep::EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangl
       triangle = &triangle->NeighborAcross(point);
       EdgeEvent( tcx, ep, *p1, triangle, *p1 );
     } else {
-      std::runtime_error("EdgeEvent - collinear points not supported");
-      assert(0);
+      throw std::runtime_error("EdgeEvent - collinear points not supported");
     }
     return;
   }
@@ -140,8 +139,7 @@ void Sweep::EdgeEvent(SweepContext& tcx, Point& ep, Point& eq, Triangle* triangl
       triangle = &triangle->NeighborAcross(point);
       EdgeEvent( tcx, ep, *p2, triangle, *p2 );
     } else {
-      std::runtime_error("EdgeEvent - collinear points not supported");
-      assert(0);
+      throw std::runtime_error("EdgeEvent - collinear points not supported");
     }
     return;
   }