We exclude 32 as a number of input for Elemwise.perform.

theano/tensor/opt.py

@@ -5059,10 +5059,10 @@ your code will run correctly, but may be slower.""")
 
 
 def elemwise_max_input_fct(node):
-    # The Elemwise.perform use numpy ufunc and they are limited to 32
+    # The Elemwise.perform use numpy ufunc and they are limited to 31
     # inputs.
     if not theano.config.cxx:
-        return 32
+        return 31
     return 1024