How can I make compilation to go through with a module inside module? I tried this, failed, a few other ways failed too. f = Compile[ {{σt, _Real, 1}, {sρ, _Complex, 1}, {dt, _Real, 1}, {x, _Real}, {nnt, _Integer}, {dqt, _Real}, {divt, _Integer}}, Module[{temp, dq = dqt, div = divt, j, h}, temp[x_] := Module[{kz = 1/2 x, σ = σt, d = dt, i, kp, c, β, r, k, ρ = sρ * 10^-6, nn = nnt}, kp = kz + 0. I; k = Sqrt[kz^2 - 4 π (ρ[[2]] - ρ[[1]])]; r = (kp - k)/(kp + k) E^(-2 kp k σ[[1]]^2); c = {{1 + 0. I, r }, {r , 1}}; kp = k; For[i = 2, i < 2 nn + 2, i++, If[EvenQ[i], k = Sqrt[kz^2 - 4 π (ρ[[3]] - ρ[[1]])]; r = (kp - k)/(kp + k) E^(-2 kp k σ[[2]]^2); β = I kp d[[1]], k = Sqrt[kz^2 - 4 π (ρ[[2]] - ρ[[1]])]; r = (kp - k)/(kp + k) E^(-2 kp k σ[[3]]^2); β = I kp d[[2]] ]; c = c.{{E^β, r E^β}, {r E^-β, E^-β}}; (*previous k*) kp = k ]; Abs[c[[2, 1]]/c[[1, 1]]]^2]; h = 0.0; For[j = 1, j < div + 1, j++, h = h + temp[x - dq/2 + dq/div*j] ]; h/div ] , CompilationTarget -> "C"]