diff --git a/tests/compile/test_builders.py b/tests/compile/test_builders.py
index 8b15ad4dda..c0ddf7e894 100644
--- a/tests/compile/test_builders.py
+++ b/tests/compile/test_builders.py
@@ -555,12 +555,15 @@ def test_outputs_consistency(self):
 
     def test_explicit_input_from_constant(self):
         x = pt.dscalar("x")
-        y = constant(1.0, name="y")
+        y = constant(1.0, dtype=x.type.dtype, name="y")
         test_ofg = OpFromGraph([x, y], [x + y])
 
         out = test_ofg(x, y)
         assert out.eval({x: 5}) == 6
 
+        out = test_ofg(x, x)
+        assert out.eval({x: 5}) == 10
+
     def test_explicit_input_from_shared(self):
         x = pt.dscalar("x")
         y = shared(1.0, name="y")
@@ -576,7 +579,10 @@ def test_explicit_input_from_shared(self):
         out = test_ofg(x, y)
         assert out.eval({x: 5}) == 6
         y.set_value(2.0)
-        assert out.eval({x: 6})
+        assert out.eval({x: 6}) == 8
+
+        out = test_ofg(y, y)
+        assert out.eval() == 4
 
 
 @config.change_flags(floatX="float64")