Deduction regression or improvement?

[Stefan Koch via Digitalmars-d]

On Tuesday, 8 March 2016 at 21:22:35 UTC, Johan Engelen wrote:
> Hi all,
>   Should the following compile or not?
>
> auto foo(T)(T start, T end) {}
> void main() {
>     const SomeStruct a;
>     SomeStruct b;
>     foo(a,b);
> }
> See http://dpaste.dzfl.pl/15581af64747
>
> DMD 2.068.2 compiles and does not complain.
> DMD 2.069.2 gives deduction error: "cannot deduce function from 
> argument types !()(const(SomeStruct), SomeStruct),   candidates 
> are:  foo(T)(T start, T end)"
>
> Is this a regression or intended?  I did not find something 
> about it in the release notes.
>
> Thanks,
>   Johan

const T is not T
Therefore this code shall not compile.