Invalid error on implicit cast from slice of sentinel terminated slices

[Vexu]

Zig Version

0.14.0-dev.3357+c44f4501e

Steps to Reproduce and Observed Behavior

comptime {
    const a: [][:0]const u8 = undefined;
    const b: [][]const u8 = a;
    _ = b;
}

a.zig:15:29: error: expected type '[][]const u8', found '[][:0]const u8'
    const b: [][]const u8 = a;
                            ^
a.zig:15:29: note: pointer type child '[:0]const u8' cannot cast into pointer type child '[]const u8'
a.zig:15:29: note: pointer sentinel '0' cannot cast into pointer sentinel 'unreachable'

Expected Behavior

No mention of pointer sentinel 'unreachable'.

[silversquirl]

this seems intended to me? b gives a view into a that allows setting elements to non-terminated slices, just like how eg. casting []*T to []?*T is not allowed but []const *T to []const ?*T is.

[Vexu]

Oh right, I didn't think of the missing const.

The error message is still incorrect though.