Fix chained comparions: remove redundant comparisons

src/core/cfg.cpp

@@ -518,7 +518,7 @@ private:
                 push_back(makeAssign(name, val));
 
                 AST_Branch* br = new AST_Branch();
-                br->test = val;
+                br->test = makeName(name, AST_TYPE::Load);
                 push_back(br);
 
                 CFGBlock* was_block = curblock;

test/tests/comparisons_chained.py

-# expected: fail
-
 class C(object):
     def __init__(self, n):
         self.n = n
@@ -17,4 +15,5 @@ def f(n):
     return C(n)
 
 # f(3) shouldn't get called:
-f(1) <= f(2) < f(1) < f(3)
+print f(1) <= f(2) < f(1) < f(3)
+print f(5) > f(3) < f(4) < f(5)