diff --git a/src/core/window-private.h b/src/core/window-private.h
index e69b1ea85..d6de1256c 100644
--- a/src/core/window-private.h
+++ b/src/core/window-private.h
@@ -584,7 +584,7 @@ struct _MetaWindowClass
   gboolean (*update_icon)        (MetaWindow       *window,
                                   cairo_surface_t **icon,
                                   cairo_surface_t **mini_icon);
-  uint32_t (*get_client_pid)     (MetaWindow *window);
+  pid_t (*get_client_pid)        (MetaWindow *window);
   void (*update_main_monitor)    (MetaWindow                   *window,
                                   MetaWindowUpdateMonitorFlags  flags);
   void (*main_monitor_changed)   (MetaWindow *window,
diff --git a/src/core/window.c b/src/core/window.c
index ad1ff6112..326e51eb2 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -296,7 +296,7 @@ meta_window_real_update_icon (MetaWindow       *window,
   return FALSE;
 }
 
-static uint32_t
+static pid_t
 meta_window_real_get_client_pid (MetaWindow *window)
 {
   return 0;
@@ -7595,7 +7595,7 @@ meta_window_get_pid (MetaWindow *window)
 {
   g_return_val_if_fail (META_IS_WINDOW (window), 0);
 
-  return META_WINDOW_GET_CLASS (window)->get_client_pid (window);
+  return (uint32_t)META_WINDOW_GET_CLASS (window)->get_client_pid (window);
 }
 
 /**
diff --git a/src/wayland/meta-window-wayland.c b/src/wayland/meta-window-wayland.c
index 47cbf1897..cef8d44a4 100644
--- a/src/wayland/meta-window-wayland.c
+++ b/src/wayland/meta-window-wayland.c
@@ -617,7 +617,7 @@ meta_window_wayland_main_monitor_changed (MetaWindow               *window,
   meta_window_emit_size_changed (window);
 }
 
-static uint32_t
+static pid_t
 meta_window_wayland_get_client_pid (MetaWindow *window)
 {
   MetaWaylandSurface *surface = window->surface;
@@ -625,7 +625,7 @@ meta_window_wayland_get_client_pid (MetaWindow *window)
   pid_t pid;
 
   wl_client_get_credentials (wl_resource_get_client (resource), &pid, NULL, NULL);
-  return (uint32_t)pid;
+  return pid;
 }
 
 static void
diff --git a/src/x11/window-x11.c b/src/x11/window-x11.c
index 1a3400499..db3fae2f0 100644
--- a/src/x11/window-x11.c
+++ b/src/x11/window-x11.c
@@ -1779,7 +1779,7 @@ meta_window_x11_main_monitor_changed (MetaWindow               *window,
 {
 }
 
-static uint32_t
+static pid_t
 meta_window_x11_get_client_pid (MetaWindow *window)
 {
   MetaX11Display *x11_display = window->display->x11_display;
@@ -1813,7 +1813,7 @@ meta_window_x11_get_client_pid (MetaWindow *window)
     }
 
   free (reply);
-  return pid;
+  return (pid_t) pid;
 }
 
 static void