fix constant folding of PrimaryCmpNode operands

Cython/Compiler/Optimize.py

@@ -3343,12 +3343,12 @@ class ConstantFolding(Visitor.VisitorTransform, SkipDeclarations):
 
     def visit_PrimaryCmpNode(self, node):
         # calculate constant partial results in the comparison cascade
+        self.visitchildren(node, ['operand1'])
         left_node = node.operand1
-        self._calculate_const(left_node)
         cmp_node = node
         while cmp_node is not None:
+            self.visitchildren(cmp_node, ['operand2'])
             right_node = cmp_node.operand2
-            self._calculate_const(right_node)
             cmp_node.constant_result = not_a_constant
             if left_node.has_constant_result() and right_node.has_constant_result():
                 try:

tests/run/constant_folding.py

@@ -428,3 +428,31 @@ def cascaded_cmp_with_partial_constants_and_false_end(a, b, c):
     """
     x = 1 < 2 < a < 4 < 5 < b < 7 < 7 < c
     return x
+
+
+@cython.test_assert_path_exists(
+    '//PrimaryCmpNode',
+    '//PrimaryCmpNode//IntNode',
+    '//PrimaryCmpNode//IntNode[@value = "0"]',
+    '//PrimaryCmpNode//IntNode[@value = "4294967296"]',
+)
+@cython.test_fail_if_path_exists(
+    '//PrimaryCmpNode//IntBinopNode',
+    '//PrimaryCmpNode//IntNode[@value = "1"]',
+    '//PrimaryCmpNode//IntNode[@value = "32"]',
+)
+def const_in_binop(v):
+    """
+    >>> const_in_binop(-1)
+    1
+    >>> const_in_binop(0)
+    0
+    >>> const_in_binop(1 << 32)
+    1
+    >>> const_in_binop(1 << 32 - 1)
+    0
+    """
+    if v < 0 or v >= (1L << 32):
+        return 1
+    else:
+        return 0