From a60581c99a8b16ae9c874b5943f22735d1e31915 Mon Sep 17 00:00:00 2001
From: Eric Wasylishen <ewasylishen@gmail.com>
Date: Mon, 11 Oct 2021 12:59:37 -0600
Subject: [PATCH] qvec: fix undefined behaviour in PolyCentroid

---
 include/common/qvec.hh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/common/qvec.hh b/include/common/qvec.hh
index 82a53cd6..ed72667f 100644
--- a/include/common/qvec.hh
+++ b/include/common/qvec.hh
@@ -423,7 +423,7 @@ template<typename Iter, typename T = typename std::iterator_traits<Iter>::value_
     else if (num_points == 1)
         return *begin;
     else if (num_points == 2)
-        return avg(*begin, *(++begin));
+        return avg(*begin, *(begin + 1));
 
     T poly_centroid{};
     value_type poly_area = 0;