destructuring problem

[lixiaoqiang]

Zig Version

0.12.0

Steps to Reproduce and Observed Behavior

    var x: i32 = 1;
    var y: i32 = 2;
    y, x = .{ x, y };
    std.debug.print("x = {d}, y = {d}\n", .{ x, y });

expect output : "x = 2, y = 1"
but get: "x = 1,y = 1"

Expected Behavior

expect output : "x = 2, y = 1"
but get: "x = 1,y = 1"

[lixiaoqiang]

May be by design?

[Rexicon226]

Afaik this is a bug. Probably caused by not copying backwards in these edge cases. Quicky bit of research shows that in Zir we are in fact not creating a temporary to hold either x or y. Copy order is irrelevant.

cc @mlugg

[nektro]

likely duplicate #12064

[Rexicon226]

It is.

[mlugg]

Yep, not a bug, just how RLS works today, and the linked issue tracks it as a design flaw.