Allow gap before first non-Lisp pseudovec member

Problem reported by Keith David Bershatsky in:
https://lists.gnu.org/r/emacs-devel/2019-04/msg00259.html
Solution suggested by Stefan Monnier in:
https://lists.gnu.org/r/emacs-devel/2019-04/msg00282.html
* src/buffer.h (BUFFER_LISP_SIZE): Simplify by using PSEUDOVECSIZE.
(BUFFER_REST_SIZE): Simplify by using VECSIZE and BUFFER_LISP_SIZE.
* src/lisp.h (PSEUDOVECSIZE): Base it on the last Lisp field,
not the first non-Lisp field.  All callers changed.  Callers
without Lisp fields changed to use ALLOCATE_PLAIN_PSEUDOVECTOR.
(ALLOCATE_PLAIN_PSEUDOVECTOR): New macro.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/frame.c b/src/frame.c
index 6fdb7d0cbb9..192ef4244fb 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -798,7 +798,8 @@ adjust_frame_size (struct frame *f, int new_width, int new_height, int inhibit,
 static struct frame *
 allocate_frame (void)
 {
-  return ALLOCATE_ZEROED_PSEUDOVECTOR (struct frame, face_cache, PVEC_FRAME);
+  return ALLOCATE_ZEROED_PSEUDOVECTOR (struct frame, tool_bar_items,
+                                       PVEC_FRAME);
 }
 
 struct frame *