Unexpected behavior when creating a slice of another slice

[hronro]

Zig Version

0.9.0

Steps to Reproduce

const foo = "12345678";
const bar = foo[2..7]; // "34567"
const baz = bar[1..3];

Expected Behavior

baz is "45".

Actual Behavior

baz is "34".

[squeek502]

Note: changing bar to var makes it work as expected:

const foo = "12345678";
var bar = foo[2..7]; // "34567"
const baz = bar[1..3]; // "45"

[nektro]

using slices also makes it work

const foo: []const u8 = "hello world";
const bar: []const u8 = foo[2..7];
const baz: []const u8 = bar[1..3];

but the bug remains when using the default types

const foo: *const [11:0]u8 = "hello world";
const bar: *const [5]u8 = foo[2..7];
const baz: *const [2]u8 = bar[1..3];

[matu3ba]

More awkwardness:

const std = @import("std");
pub fn main() !void {
    const foo = "1234";
    const bar = foo[0..4]; // "1234"
    const s2 = bar[1..2]; // "2"
    std.debug.print("s2: {s} {s}\n", .{ s2, @TypeOf(s2) }); // outputs 1 with type [1]u8
    const s3 = bar[2..3]; // "3"
    std.debug.print("s3: {s} {s}\n", .{ s3, @TypeOf(s3) }); // outputs 1 with type [1]u8
    const s4 = bar[3..4]; // "4"
    std.debug.print("s4: {s} {s}\n", .{ s4, @TypeOf(s4) }); // outputs 1 with type [1:0]u8
    const s5 = bar[2..4]; // "3"
    std.debug.print("s5: {s} {s}\n", .{ s5, @TypeOf(s5) }); // outputs 12 with type [2:0]u8
    const s6 = bar[3..4]; // "3"
    std.debug.print("s6: {s} {s}\n", .{ s6, @TypeOf(s6) }); // outputs 1 with type [1:0]u8
}

output

!zig run test.zig
s2: 1 *const [1]u8
s3: 1 *const [1]u8
s4: 1 *const [1:0]u8
s5: 12 *const [2:0]u8
s6: 1 *const [1:0]u8

I suspect quite abit comptime slice stuff is related (and was never fixed): #8304 #6905
Probably also #8646 and others.