Incorrect error message when concatting sliced comptime only type

[CurtisFenner]

The following program crashes with the given output on my Windows 10 computer:

>zig version
0.6.0

>zig test src/min.zig
Unreachable at D:\a\1\s\src\ir.cpp:28528 in buf_write_value_bytes. This is a bug in the Zig compiler.
Unable to dump stack trace: debug info stripped

const S = struct {};

test "Crashes" {
    const cc = &[_]type{ S, S };
    const init = cc[0..1];
    const dd = init ++ [_]type{S};
}

This is a slightly different error message from what I started with:

Unreachable at D:\a\1\s\src\ir.cpp:28562 in buf_write_value_bytes. This is a bug in the Zig compiler.

That version used a const struct { field: type } instead of type directly, which may or may not be the cause of the difference.

[alexnask]

Thanks for the small testcase :)
I will try to fix this later

[Vexu]

Using the self-hosted compiler the example works when specifying init to be []const type but without that it produces an incorrect error message:

a.zig:18:16: error: comptime dereference requires '[1]type' to have a well-defined layout, but it does not.
    const dd = init ++ &[_]type{S};
               ^~~~