diff --git a/pgtap/withPoints/issue1640.sql b/pgtap/withPoints/issue1640.sql
new file mode 100644
index 00000000000..c3818210a6a
--- /dev/null
+++ b/pgtap/withPoints/issue1640.sql
@@ -0,0 +1,25 @@
+\i setup.sql
+
+SELECT plan(4);
+
+PREPARE q1 AS
+SELECT * FROM pgr_withPoints (
+    'SELECT id, source, target, cost, reverse_cost FROM edge_table',
+    'SELECT pid, edge_id, fraction FROM pointsOfInterest WHERE pid IN (-1)',
+    1, -2
+);
+
+SELECT * FROM lives_ok('q1');
+SELECT * FROM is_empty('q1');
+
+PREPARE q2 AS
+SELECT * FROM pgr_withPoints (
+    'SELECT id, source, target, cost, reverse_cost FROM edge_table',
+    'SELECT pid, edge_id, fraction FROM pointsOfInterest WHERE pid IN (-1)',
+    1, 2
+);
+
+SELECT * FROM lives_ok('q2');
+SELECT * FROM isnt_empty('q2');
+
+SELECT finish();
diff --git a/pgtap/withPoints/withPoints_oneToOne-compare-dijkstra.test.sql b/pgtap/withPoints/withPoints_oneToOne-compare-dijkstra.test.sql
new file mode 100644
index 00000000000..5d900a8e967
--- /dev/null
+++ b/pgtap/withPoints/withPoints_oneToOne-compare-dijkstra.test.sql
@@ -0,0 +1,98 @@
+/*PGR-GNU*****************************************************************
+
+Copyright (c) 2020 pgRouting developers
+Mail: project@pgrouting.org
+
+------
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+********************************************************************PGR-GNU*/
+
+\i setup.sql
+
+SELECT plan(1156);
+
+SET extra_float_digits = -3;
+
+UPDATE edge_table SET cost = sign(cost) + 0.001 * id * id, reverse_cost = sign(reverse_cost) + 0.001 * id * id;
+
+CREATE or REPLACE FUNCTION withPointsCompareDijkstra(cant INTEGER default 17)
+RETURNS SETOF TEXT AS
+$BODY$
+DECLARE
+inner_sql TEXT;
+points_sql TEXT;
+dijkstra_sql TEXT;
+withPoints_sql TEXT;
+result_columns TEXT;
+BEGIN
+    result_columns := 'seq, path_seq, node, edge, cost, agg_cost';
+    points_sql := 'SELECT pid, edge_id, fraction, side from pointsOfInterest WHERE pid IN (-1)';
+
+    FOR i IN 1.. cant LOOP
+        FOR j IN 1.. cant LOOP
+
+            -- DIRECTED WITH REVERSE COST
+            inner_sql := 'SELECT id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM edge_table';
+            dijkstra_sql := 'SELECT ' || result_columns || ' FROM pgr_dijkstra($$' || inner_sql || '$$, ' || i || ', ' || j
+                || ', directed => true)';
+
+            withPoints_sql := 'SELECT ' || result_columns || ' FROM pgr_withPoints($$' || inner_sql || '$$, $$' || points_sql
+                || '$$, ' || i || ', ' || j || ', directed => true)';
+            RETURN query SELECT set_eq(withPoints_sql, dijkstra_sql, withPoints_sql);
+
+            -- DIRECTED WITHOUT REVERSE COST
+            inner_sql := 'SELECT id, source, target, cost, x1, y1, x2, y2 FROM edge_table';
+            dijkstra_sql := 'SELECT ' || result_columns || ' FROM pgr_dijkstra($$' || inner_sql || '$$, ' || i || ', ' || j
+                || ', directed => true)';
+
+            withPoints_sql := 'SELECT ' || result_columns || ' FROM pgr_withPoints($$' || inner_sql || '$$, $$' || points_sql
+                || '$$, ' || i || ', ' || j || ', directed => true)';
+            RETURN query SELECT set_eq(withPoints_sql, dijkstra_sql, withPoints_sql);
+
+
+            -- UNDIRECTED WITH REVERSE COST
+            inner_sql := 'SELECT id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM edge_table';
+            dijkstra_sql := 'SELECT ' || result_columns || ' FROM pgr_dijkstra($$' || inner_sql || '$$, ' || i || ', ' || j
+                || ', directed => false)';
+
+            withPoints_sql := 'SELECT ' || result_columns || ' FROM pgr_withPoints($$' || inner_sql || '$$, $$' || points_sql
+                || '$$, ' || i || ', ' || j || ', directed => false)';
+            RETURN query SELECT set_eq(withPoints_sql, dijkstra_sql, withPoints_sql);
+
+            -- UNDIRECTED WITHOUT REVERSE COST
+            inner_sql := 'SELECT id, source, target, cost, x1, y1, x2, y2 FROM edge_table';
+            dijkstra_sql := 'SELECT ' || result_columns || ' FROM pgr_dijkstra($$' || inner_sql || '$$, ' || i || ', ' || j
+                || ', directed => false)';
+
+            withPoints_sql := 'SELECT ' || result_columns || ' FROM pgr_withPoints($$' || inner_sql || '$$, $$' || points_sql
+                || '$$, ' || i || ', ' || j || ', directed => false)';
+            RETURN query SELECT set_eq(withPoints_sql, dijkstra_sql, withPoints_sql);
+
+        END LOOP;
+    END LOOP;
+
+    RETURN;
+END
+$BODY$
+language plpgsql;
+
+SELECT * from withPointsCompareDijkstra();
+
+
+SELECT * FROM finish();
+ROLLBACK;
+
diff --git a/src/withPoints/withPoints_driver.cpp b/src/withPoints/withPoints_driver.cpp
index 9e1d138f697..994afc4f433 100644
--- a/src/withPoints/withPoints_driver.cpp
+++ b/src/withPoints/withPoints_driver.cpp
@@ -113,7 +113,6 @@ do_pgr_withPoints(
         pgassert(!(*return_tuples));
         pgassert((*return_count) == 0);
         pgassert(edges || edges_of_points);
-        pgassert(points_p);
         pgassert(start_pidsArr);
         pgassert(end_pidsArr);