fn bind(&mut self...) is invalid pointer about wayland-rs HOT 6 CLOSED

$rust-gdb compositor
(gdb) b  wayland_server::event_loop::global_bind::{{closure}}<wayland_server::generated::server::wl_compositor::WlCompositor,rwc::CompositorGlobal>
(gdb) run
Breakpoint 1 ...
let data = &*(data as ...);
(gdb) n
let handler = data.0;
(gdb) print data[0]
$1 = {0x1, 0x3}

So the self pointer is already invalid when global_bind is called

from wayland-rs.

The data = Box::new(...) in register_global has the same address as data in global_bind, some somewhere betwen the two something's overwriting that memory.

from wayland-rs.

Okay, this is very concerning.

Running your first code, I get this

Breakpoint 1, compositor::{{impl}}::bind (self=0xc000100000001, evqh=0x3, global=WlCompositor = {...})

Looks like I only get evqh to be corrupted, not self ? Are your running this on wayland-server 0.9.3 ?

The second one gives me the same thing: $1 = {0xc000100000001, 0x3}

from wayland-rs.

well no, looks like when the user data is set in register_global, the values are {0x7ffff6636000, 0x7ffff661f060}...

from wayland-rs.

Oh well...

Hardware watchpoint 2: *0x7ffff6636010

Old value = -161259520
New value = 0
0x00007ffff7bd3bdd in wl_map_insert_at () from /usr/lib/libwayland-server.so.0

from wayland-rs.

Alright, found. When the Global object returned by register_global is destroyed, it frees the backing storage of the user data...

This is plainly wrong, as it's documented that you can let it go out of scope. I'll correct this.

from wayland-rs.