I'm converting an expression to optimized Matlab code, and some key parentheses were left out of the final expression. Is this a known bug? I'll include the offending code below:

W1 := (-5+6*b*c*d^2+5*a*b^3*c*d+5*a*b*c^3*d+a*b*c*d+a*b^3*c^3*d-2*a*b*c*d^3-4*a*b^2*c^2*d-b^4+6*b^2+6*c^2-c^4+4*d^2-2*b^2*c^2*d^2-3*b^2*c^2+3*b^4*c^2+3*b*c+3*b^2*c^4-5*b*c^3-5*b^3*c-b^3*c^3-4*d^2*b^2-4*d^2*c^2+8*a*d-8*a*d*b^2-8*a*d*c^2)/(-2*a*b*c*d+2*b*c+2*a*d-c^2-b^2+d^2)^(7/2)/(-d+2*a);

with(CodeGeneration);

Matlab(W1,optimize);

I get a final expression of

t72 = t32 + t57 / t65 / t63 / t62 / -d + 2 * a;