cbe: @bitCast between bool vectors and integers differs to LLVM backend

[notcancername]

Zig Version

0.11.0-dev.4403+e84cda0eb

Steps to Reproduce and Observed Behavior

1. Create a source file containing the following code:

test "bool vector bitcast" {
    var v: @Vector(8, bool) = .{ false, false, false, false, false, false, false, false };
    try std.testing.expectEqual(@as(u8, 0b0000_0000), @as(u8, @bitCast(v)));
    v[0] = true;
    try std.testing.expectEqual(@as(u8, 0b0000_0001), @as(u8, @bitCast(v)));
    v[1] = true;
    try std.testing.expectEqual(@as(u8, 0b0000_0011), @as(u8, @bitCast(v)));
    v[2] = true;
    try std.testing.expectEqual(@as(u8, 0b0000_0111), @as(u8, @bitCast(v)));
    v[0] = false;
    try std.testing.expectEqual(@as(u8, 0b0000_0110), @as(u8, @bitCast(v)));
    v[7] = true;
    try std.testing.expectEqual(@as(u8, 0b1000_0110), @as(u8, @bitCast(v)));
}

2. Run zig test source.zig -O ReleaseSmall on your x86_64 machine. The test passes.
3. Run zig test source.zig -ofmt=c -O ReleaseSmall. The test fails:

Test [1/1] test.bool vector bitcast... expected 3, found 1
Test [1/1] test.bool vector bitcast... FAIL (TestExpectedEqual)
0 passed; 0 skipped; 1 failed.
error: the following test command failed with exit code 1:
/home/user/Downloads/zig/zig run -I /home/user/Downloads/zig/lib /home/user/src/random/zig-cache/o/c108104757f433d5803b478dd6f1fe39/test.c

Note that the generated code for this source:

export fn return_bool_vector_bitcast() u8 {
    var v: @Vector(8, bool) = .{false, false, false, false, false, false, true, true };
    return @bitCast(v);
}

is:

uint8_t return_bool_vector_bitcast(void) {
 static bool const t1[8] = {false,false,false,false,false,false,true,true};
 bool t2[8];
 bool t0[8];
 uint8_t t3;
 memcpy((char *)&t0, t1, sizeof(bool[8]));
 memcpy(t2, (const char *)&t0, sizeof(bool[8]));
 memcpy(&t3, &t2, sizeof(uint8_t));
 t3 = zig_wrap_u8(t3, UINT8_C(8));
 return t3;
}

Note that in the generated code, sizeof(uint8_t) clearly is not equal to sizeof(bool[8]). Note that no check for this is emitted, even in debug mode.

Expected Behavior

I expected the behavior to match that of the LLVM backend, although the semantics of @bitCast between bool vectors and integers are not yet specified.