const std = @import("std");
const SinglyLinkedList = std.SinglyLinkedList;

pub fn main() !void {
    const List = struct {
        node: SinglyLinkedList.Node = .{},
    };
    var list: SinglyLinkedList = .{};

    var one: List = .{};
    var two: List = .{};

    list.prepend(&one.node);
    one.node.insertAfter(&two.node);
    _ = list.remove(&two.node);
    _ = list.remove(&two.node);
}

havelock@pop-os:~/code/scr$ zig run sll_error.zig 
thread 134888 panic: attempt to use null value
/home/havelock/bin/zig/lib/std/SinglyLinkedList.zig:94:43: 0x1137b3b in remove (std.zig)
            current_elm = current_elm.next.?;
                                          ^
/home/havelock/code/scr/sll_error.zig:16:20: 0x11364ff in main (sll_error.zig)
    _ = list.remove(&two.node);
                   ^
/home/havelock/bin/zig/lib/std/start.zig:627:37: 0x1136cad in posixCallMainAndExit (std.zig)
            const result = root.main() catch |err| {
                                    ^
/home/havelock/bin/zig/lib/std/start.zig:232:5: 0x1136421 in _start (std.zig)
    asm volatile (switch (native_arch) {
    ^
???:?:?: 0x0 in ??? (???)
Aborted (core dumped)