Issue when dealing with expressions that contain a cubic term in an intermediate step

[Eric-Luu]

If I have 3 binary bits a, b, and c, then the equation:

h = abc + (1-a) (1-b) (1-c)

should evaluate to:

h = ab + ac + bc - a - b - c + 1

However, the resulting compiled structure of h = abc + (1-a) (1-b) (1-c) still keeps an a*b term.