Fix test and remove upcast to float64.

theano/compile/tests/test_builders.py

@@ -318,10 +318,10 @@ class T_OpFromGraph(unittest_tools.InferShapeTester):
     @theano.configparser.change_flags(compute_test_value='raise')
     def test_compute_test_value(self):
         x = T.scalar('x')
-        x.tag.test_value = np.array(1.)
+        x.tag.test_value = np.array(1., dtype=config.floatX)
         op = OpFromGraph([x], [x ** 3])
         y = T.scalar('y')
-        y.tag.test_value = np.array(1.)
+        y.tag.test_value = np.array(1., dtype=config.floatX)
         f = op(y)
         grad_f = T.grad(f, y)
         assert grad_f.tag.test_value is not None

theano/tensor/opt.py

@@ -5718,6 +5718,11 @@ def local_opt_alloc(node):
                     assert val.size == 1
                     # check which type of op
                     size = T.mul(*shapes)
+                    if input.dtype == "float32":
+                        # shapes are ints and normally int64.
+                        # We don't want to have a float64 upcast here
+                        # if input is a float32.
+                        size = size.astype(input.dtype)
                     if isinstance(node.op, T.Sum):
                         val = val.reshape(1)[0] * size
                     else: