From 709d06e89e858cf907e17b5104b4cfa74486dd77 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michel=20D=C3=A4nzer?= <mdaenzer@redhat.com>
Date: Fri, 17 Jun 2022 16:33:17 +0200
Subject: [PATCH] wayland/surface: The same sub-surface is not a valid sibling

The Wayland protocol documentation at
https://wayland.app/protocols/wayland#wl_subsurface:request:place_above
says:

 The reference surface must be one of the sibling surfaces, or the
 parent surface. Using any other surface, including this sub-surface,
 will cause a protocol error.

v2:
* Leave it as a single line. (Georges Basile Stavracas Neto)

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2525>
---
 src/wayland/meta-wayland-subsurface.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/wayland/meta-wayland-subsurface.c b/src/wayland/meta-wayland-subsurface.c
index 4055e6882..3e088b04f 100644
--- a/src/wayland/meta-wayland-subsurface.c
+++ b/src/wayland/meta-wayland-subsurface.c
@@ -102,7 +102,7 @@ static gboolean
 is_sibling (MetaWaylandSurface *surface,
             MetaWaylandSurface *sibling)
 {
-  return surface->sub.parent == sibling->sub.parent;
+  return surface != sibling && surface->sub.parent == sibling->sub.parent;
 }
 
 static gboolean