[vte] spawn: Warn if G_SPAWN_LEAVE_DESCRIPTORS_OPEN is passed

[Christian Persch <chpe src gnome org>]

commit 9356270ec482a0a3b8ed1cdc9af1902da4968f04
Author: Christian Persch <chpe src gnome org>
Date:   Sat Oct 12 20:10:55 2019 +0200

    spawn: Warn if G_SPAWN_LEAVE_DESCRIPTORS_OPEN is passed
    
    This flag has never been supported by vte, so warn if it is passed.
    In future, this may become a g_return_if_fail() precondition.

 src/vtegtk.cc | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/vtegtk.cc b/src/vtegtk.cc
index be8db362..8b8e640c 100644
--- a/src/vtegtk.cc
+++ b/src/vtegtk.cc
@@ -2872,6 +2872,7 @@ vte_terminal_spawn_async(VteTerminal *terminal,
          * process, simply use a child setup function that unsets the CLOEXEC flag
          * on that FD.
          */
+        g_warn_if_fail((spawn_flags & G_SPAWN_LEAVE_DESCRIPTORS_OPEN) == 0);
         spawn_flags &= ~G_SPAWN_LEAVE_DESCRIPTORS_OPEN;
 
         vte_pty_spawn_async(pty,