check instance of nested variadic template

[Lodovico Giaretta via Digitalmars-d-learn]

On Saturday, 5 November 2016 at 13:34:51 UTC, Gianni Pisetta 
wrote:
> When i have time i will test it with ldc and see if the result 
> is the same, then it will probably be a front-end bug and i 
> will report it as an issue.

I think it has already been reported.

https://issues.dlang.org/show_bug.cgi?id=13372