chris_one pointed me at a paper that eventually led to me producing this OCaml gem:Note that we never actually use x, and instead just assign to q. So the ensuing grinding is just a product of the type-inferencer.
let q = let x = 1 in let x1 = (x, x) in let x2 = (x1, x1) in let x3 = (x2, x2) in let x4 = (x3, x3) in let x5 = (x4, x4) in let x6 = (x5, x5) in let x7 = (x6, x6) in let x8 = (x7, x7) in let x9 = (x8, x8) in let x10 = (x9, x9) in let x11 = (x10, x10) in let x12 = (x11, x11) in let x13 = (x12, x12) in let x14 = (x13, x13) in let x15 = (x14, x14) in let x16 = (x15, x15) in let x17 = (x16, x16) in let x18 = (x17, x17) in let x19 = (x18, x18) in let x20 = (x19, x19) in x20 in 1
Reminds me a lot of that "million laughs" XML attack, where you create entities that expand recursively.