[MLton] Bug with tuple selection

[Wesley W. Terpstra]

The version: cvs HEAD/powerpc

The error:
> 	 xmlSimplify starting
> 	    typeCheck starting
> Type error: actual and formal not of same type
> actual: ('a_4092 * word32) * (word32 * word32)
> formal: (word32 * word32) * (word32 * word32)
> expression: f x_0
> 	    typeCheck raised in 0.06 + 0.00 (0% GC)

The code:
> fun f (a, b) = Int.< (#value a, #value b)
>
> fun copyTo (array, record as {value, offset}) =
>   Array.update (array, 1, { value=value, offset = 3 })
>
> fun fixTooBig (array, record) =
>   let val left = Array.sub (array, 1)
>       val right = Array.sub (array, 2)
>       val small = if f (left, right) then left else right
>   in  if f (record, small)
>       then copyTo (array, record)
>       else copyTo (array, small)
>   end