Fixes comments from review.

theano/scalar/basic.py

@@ -3831,16 +3831,17 @@ class Compositef32(object):
             for i in node.inputs:
                 if i not in mapping:
                     assert type(i) is ScalarConstant
+                    if i.type == float16:
+                        i = ScalarConstant(float32, i.data)
                     mapping[i] = i
             if type(node.op) in self.special:
                 self.special[type(node.op)](node, mapping)
                 continue
-            # make sure we won't produce any float16.
-            assert not any(o.dtype == 'float16' for o in
-                           node.op.output_types([mapping[i].type for i in node.inputs]))
             new_node = node.clone_with_new_inputs(
                 [mapping[i] for i in node.inputs],
                 strict=False)
+            # make sure we don't produce any float16.
+            assert not any(o.dtype == 'float16' for o in new_node.outputs)
             for o, no in zip(node.outputs, new_node.outputs):
                 mapping[o] = no
 

theano/scalar/tests/test_basic.py

@@ -25,7 +25,7 @@ from theano.scalar.basic import (floats, float16, float32, float64,
                                  ComplexError, IntDiv, TrueDiv,
                                  Composite, add, div_proxy,
                                  and_, eq, neq, invert, mul, Scalar, InRange,
-                                 cast)
+                                 cast, constant)
 from theano.scalar.basic import (
     true_div, inv, log, log2, log10, log1p, exp, exp2, expm1, sqrt, deg2rad,
     rad2deg, cos, arccos, sin, arcsin, tan, arctan, arctan2, cosh, arccosh,
@@ -68,11 +68,8 @@ class test_ScalarOps(unittest.TestCase):
 
 
 def has_f16(comp):
-    if any(i.type == float16 for i in comp.fgraph.inputs):
+    if any(v.type == float16 for v in comp.fgraph.variables):
         return True
-    for n in comp.fgraph.apply_nodes:
-        if any(o.type == float16 for o in n.outputs):
-            return True
     return False
 
 
@@ -83,8 +80,9 @@ class test_composite(unittest.TestCase):
         y = float32()
         cz = Composite([x, y], [tanh(x + cast(y, 'float16'))])
         c = Composite([w, x, y], [cz(x, y) - cz(x, y)**2 +
-                               cast(x, 'int16') + cast(x, 'float32') +
-                               cast(w, 'float16')])
+                                  cast(x, 'int16') + cast(x, 'float32') +
+                                  cast(w, 'float16') -
+                                  constant(np.float16(1.0))])
         assert has_f16(c)
         nc = c.clone_float32()
         assert not has_f16(nc)