Remove `all_buffers` and the associated `next` field of buffers

* src/alloc.c (enum mem_type): Remove MEM_TYPE_BUFFER.
(allocate_buffer): Allocate like any other pseudovector.
Don't register on `all_buffers` any more.
(live_buffer_holding, live_buffer_p): Delete functions.
(mark_maybe_object, valid_lisp_object_p): Don't pay attention to
MEM_TYPE_BUFFER any more.
(garbage_collect): Only compact the live buffers.
(mark_buffer): Mark the undo_list of dead buffers here.
(mark_object): Buffers are normal pseudovectors now.
(sweep_buffers): Don't do the actual sweep here, just cleanup the
markers and only for live buffers.

* src/buffer.c (all_buffers): Remove variable.
(Fkill_buffer): Don't check indirect dead buffers.
Set the undo_list before we remove ourselves from the list of live buffers.
(Fbuffer_swap_text, Fset_buffer_multibyte): Don't check indirect dead
buffers.
(init_buffer_once): Don't set `all_buffers`.
(init_buffer): Don't map new memory for dead buffers.

* src/buffer.h (struct buffer): Remove `next` field.
(FOR_EACH_BUFFER): Remove macro.

* src/pdumper.c (dump_buffer): Don't dump the `next` field.

1 files changed, 0 insertions, 12 deletions

diff --git a/src/buffer.h b/src/buffer.h
index 31f497ea40a..abb1294d038 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -570,9 +570,6 @@ struct buffer
      In an indirect buffer, this is the own_text field of another buffer.  */
   struct buffer_text *text;
 
-  /* Next buffer, in chain of all buffers, including killed ones.  */
-  struct buffer *next;
-
   /* Char position of point in buffer.  */
   ptrdiff_t pt;
 
@@ -1104,15 +1101,6 @@ BUFFER_CHECK_INDIRECTION (struct buffer *b)
     }
 }
 
-/* Chain of all buffers, including killed ones.  */
-
-extern struct buffer *all_buffers;
-
-/* Used to iterate over the chain above.  */
-
-#define FOR_EACH_BUFFER(b) \
-  for ((b) = all_buffers; (b); (b) = (b)->next)
-
 /* This structure holds the default values of the buffer-local variables
    that have special slots in each buffer.
    The default value occupies the same slot in this structure