> Please take time to file a smallish test cases that gets this ICE.
> Don is very interested in any CTFE-related ICE (and ICEs in general are important!l).

I apologize, but I'm having trouble re-creating the bug, let alone doing a reduced test case.

Anyways, *these* two lines alone are enough to create the issue:

1. Take the existing std.uni.
2. Add the `std.typecons` insert (the ` : Tuple`) is optional.
3. add the  insert these two lines here (don't change the rest of `toLower`))
4. `rdmd --main -unittest std/format.d`
5. Crash in `std.conv`.

Is this worth creating an entry, or is the problem too specific?