make it explicit where type sorting is used in fused function dispatch

Cython/Compiler/FusedNode.py

@@ -483,8 +483,10 @@ class FusedCFuncDefNode(StatListNode):
         Specialize fused types and split into normal types and buffer types.
         """
         specialized_types = PyrexTypes.get_specialized_types(arg.type)
-        # Prefer long over int, etc
-        # specialized_types.sort()
+
+        # Prefer long over int, etc by sorting (see type classes in PyrexTypes.py)
+        specialized_types.sort()
+
         seen_py_type_names = set()
         normal_types, buffer_types = [], []
         has_object_fallback = False

Cython/Compiler/PyrexTypes.py

@@ -3011,10 +3011,10 @@ def specialization_signature_string(fused_compound_type, fused_to_specific):
 
     return fused_type.specialize(fused_to_specific).typeof_name()
 
+
 def get_specialized_types(type):
     """
-    Return a list of specialized types sorted in reverse order in accordance
-    with their preference in runtime fused-type dispatch
+    Return a list of specialized types in their declared order.
     """
     assert type.is_fused
 
@@ -3030,7 +3030,7 @@ def get_specialized_types(type):
                             specialization_signature_string(type, f2s))
             result.append(specialized_type)
 
-    return sorted(result)
+    return result
 
 
 class CFuncTypeArg(BaseType):