Change vectorlike from struct to union

* src/lisp.h (vectorlike_headed): Change from struct to union.
All uses changed.  Since it has only one member, this does not
change semantics.  This is designed to simplify future changes
needed to fix bugs like Bug#29040.  All uses changed.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/xterm.h b/src/xterm.h
index 6274630706f..7ab20ba06c6 100644
--- a/src/xterm.h
+++ b/src/xterm.h
@@ -887,7 +887,7 @@ extern void x_mark_frame_dirty (struct frame *f);
 struct scroll_bar
 {
   /* These fields are shared by all vectors.  */
-  struct vectorlike_header header;
+  union vectorlike_header header;
 
   /* The window we're a scroll bar for.  */
   Lisp_Object window;