Merge from trunk.

1 files changed, 242 insertions, 232 deletions

diff --git a/src/buffer.c b/src/buffer.c
index d512547d34e..abebdf21135 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -1,6 +1,7 @@
 /* Buffer manipulation primitives for GNU Emacs.
 
-Copyright (C) 1985-1989, 1993-1995, 1997-2012 Free Software Foundation, Inc.
+Copyright (C) 1985-1989, 1993-1995, 1997-2013 Free Software Foundation,
+Inc.
 
 This file is part of GNU Emacs.
 
@@ -26,7 +27,6 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <sys/param.h>
 #include <errno.h>
 #include <stdio.h>
-#include <setjmp.h>
 #include <unistd.h>
 
 #include <verify.h>
@@ -151,230 +151,227 @@ static void modify_overlay (struct buffer *, ptrdiff_t, ptrdiff_t);
 static Lisp_Object buffer_lisp_local_variables (struct buffer *, bool);
 
 /* These setters are used only in this file, so they can be private.  */
-static inline void
+static void
 bset_abbrev_mode (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (abbrev_mode) = val;
 }
-static inline void
+static void
 bset_abbrev_table (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (abbrev_table) = val;
 }
-static inline void
+static void
 bset_auto_fill_function (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (auto_fill_function) = val;
 }
-static inline void
+static void
 bset_auto_save_file_format (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (auto_save_file_format) = val;
 }
-static inline void
+static void
 bset_auto_save_file_name (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (auto_save_file_name) = val;
 }
-static inline void
+static void
 bset_backed_up (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (backed_up) = val;
 }
-static inline void
+static void
 bset_begv_marker (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (begv_marker) = val;
 }
-static inline void
+static void
 bset_bidi_display_reordering (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (bidi_display_reordering) = val;
 }
-static inline void
+static void
 bset_buffer_file_coding_system (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (buffer_file_coding_system) = val;
 }
-static inline void
+static void
 bset_cache_long_line_scans (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (cache_long_line_scans) = val;
 }
-static inline void
+static void
 bset_case_fold_search (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (case_fold_search) = val;
 }
-static inline void
+static void
 bset_ctl_arrow (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (ctl_arrow) = val;
 }
-static inline void
+static void
 bset_cursor_in_non_selected_windows (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (cursor_in_non_selected_windows) = val;
 }
-static inline void
+static void
 bset_cursor_type (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (cursor_type) = val;
 }
-static inline void
+static void
 bset_display_table (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (display_table) = val;
 }
-static inline void
+static void
 bset_extra_line_spacing (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (extra_line_spacing) = val;
 }
-static inline void
+static void
 bset_file_format (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (file_format) = val;
 }
-static inline void
+static void
 bset_file_truename (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (file_truename) = val;
 }
-static inline void
+static void
 bset_fringe_cursor_alist (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (fringe_cursor_alist) = val;
 }
-static inline void
+static void
 bset_fringe_indicator_alist (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (fringe_indicator_alist) = val;
 }
-static inline void
+static void
 bset_fringes_outside_margins (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (fringes_outside_margins) = val;
 }
-static inline void
+static void
 bset_header_line_format (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (header_line_format) = val;
 }
-static inline void
+static void
 bset_indicate_buffer_boundaries (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (indicate_buffer_boundaries) = val;
 }
-static inline void
+static void
 bset_indicate_empty_lines (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (indicate_empty_lines) = val;
 }
-static inline void
+static void
 bset_invisibility_spec (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (invisibility_spec) = val;
 }
-static inline void
+static void
 bset_left_fringe_width (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (left_fringe_width) = val;
 }
-static inline void
+static void
 bset_major_mode (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (major_mode) = val;
 }
-static inline void
+static void
 bset_mark (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (mark) = val;
 }
-static inline void
+static void
 bset_minor_modes (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (minor_modes) = val;
 }
-static inline void
+static void
 bset_mode_line_format (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (mode_line_format) = val;
 }
-static inline void
+static void
 bset_mode_name (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (mode_name) = val;
 }
-static inline void
+static void
 bset_name (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (name) = val;
 }
-static inline void
+static void
 bset_overwrite_mode (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (overwrite_mode) = val;
 }
-static inline void
+static void
 bset_pt_marker (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (pt_marker) = val;
 }
-static inline void
+static void
 bset_right_fringe_width (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (right_fringe_width) = val;
 }
-static inline void
+static void
 bset_save_length (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (save_length) = val;
 }
-static inline void
+static void
 bset_scroll_bar_width (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (scroll_bar_width) = val;
 }
-static inline void
+static void
 bset_scroll_down_aggressively (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (scroll_down_aggressively) = val;
 }
-static inline void
+static void
 bset_scroll_up_aggressively (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (scroll_up_aggressively) = val;
 }
-static inline void
+static void
 bset_selective_display (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (selective_display) = val;
 }
-static inline void
+static void
 bset_selective_display_ellipses (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (selective_display_ellipses) = val;
 }
-static inline void
+static void
 bset_vertical_scroll_bar_type (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (vertical_scroll_bar_type) = val;
 }
-static inline void
+static void
 bset_word_wrap (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (word_wrap) = val;
 }
-static inline void
+static void
 bset_zv_marker (struct buffer *b, Lisp_Object val)
 {
   b->INTERNAL_FIELD (zv_marker) = val;
 }
 
-/* For debugging; temporary.  See set_buffer_internal.  */
-/* Lisp_Object Qlisp_mode, Vcheck_symbol; */
-
 void
 nsberror (Lisp_Object spec)
 {
@@ -407,7 +404,6 @@ followed by the rest of the buffers.  */)
       Lisp_Object framelist, prevlist, tail;
       Lisp_Object args[3];
 
-      CHECK_FRAME (frame);
       framelist = Fcopy_sequence (XFRAME (frame)->buffer_list);
       prevlist = Fnreverse (Fcopy_sequence
                             (XFRAME (frame)->buried_buffer_list));
@@ -549,13 +545,15 @@ even if it is dead.  The return value is never nil.  */)
   b->base_buffer = NULL;
   /* No one shares the text with us now.  */
   b->indirections = 0;
+  /* No one shows us now.  */
+  b->window_count = 0;
 
   BUF_GAP_SIZE (b) = 20;
-  BLOCK_INPUT;
+  block_input ();
   /* We allocate extra 1-byte at the tail and keep it always '\0' for
      anchoring a search.  */
   alloc_buffer_text (b, BUF_GAP_SIZE (b) + 1);
-  UNBLOCK_INPUT;
+  unblock_input ();
   if (! BUF_BEG_ADDR (b))
     buffer_memory_full (BUF_GAP_SIZE (b) + 1);
 
@@ -575,6 +573,7 @@ even if it is dead.  The return value is never nil.  */)
   BUF_CHARS_MODIFF (b) = 1;
   BUF_OVERLAY_MODIFF (b) = 1;
   BUF_SAVE_MODIFF (b) = 1;
+  BUF_COMPACT (b) = 1;
   set_buffer_intervals (b, NULL);
   BUF_UNCHANGED_MODIFIED (b) = 1;
   BUF_OVERLAY_UNCHANGED_MODIFIED (b) = 1;
@@ -652,13 +651,13 @@ copy_overlays (struct buffer *b, struct Lisp_Overlay *list)
 
 /* Set an appropriate overlay of B.  */
 
-static inline void
+static void
 set_buffer_overlays_before (struct buffer *b, struct Lisp_Overlay *o)
 {
   b->overlays_before = o;
 }
 
-static inline void
+static void
 set_buffer_overlays_after (struct buffer *b, struct Lisp_Overlay *o)
 {
   b->overlays_after = o;
@@ -796,6 +795,8 @@ CLONE nil means the indirect buffer's state is reset to default values.  */)
   b->indirections = -1;
   /* Notify base buffer that we share the text now.  */
   b->base_buffer->indirections++;
+  /* Always -1 for an indirect buffer.  */
+  b->window_count = -1;
 
   b->pt = b->base_buffer->pt;
   b->begv = b->base_buffer->begv;
@@ -898,6 +899,8 @@ delete_all_overlays (struct buffer *b)
 {
   struct Lisp_Overlay *ov, *next;
 
+  /* FIXME: Since each drop_overlay will scan BUF_MARKERS to unlink its
+     markers, we have an unneeded O(N^2) behavior here.  */
   for (ov = b->overlays_before; ov; ov = next)
     {
       drop_overlay (b, ov);
@@ -1336,15 +1339,19 @@ DEFUN ("set-buffer-modified-p", Fset_buffer_modified_p, Sset_buffer_modified_p,
 A non-nil FLAG means mark the buffer modified.  */)
   (Lisp_Object flag)
 {
-  Lisp_Object fn, buffer, window;
+  Lisp_Object fn;
 
 #ifdef CLASH_DETECTION
   /* If buffer becoming modified, lock the file.
      If buffer becoming unmodified, unlock the file.  */
 
-  fn = BVAR (current_buffer, file_truename);
+  struct buffer *b = current_buffer->base_buffer
+    ? current_buffer->base_buffer
+    : current_buffer;
+
+  fn = BVAR (b, file_truename);
   /* Test buffer-file-name so that binding it to nil is effective.  */
-  if (!NILP (fn) && ! NILP (BVAR (current_buffer, filename)))
+  if (!NILP (fn) && ! NILP (BVAR (b, filename)))
     {
       bool already = SAVE_MODIFF < MODIFF;
       if (!already && !NILP (flag))
@@ -1385,9 +1392,7 @@ A non-nil FLAG means mark the buffer modified.  */)
      Ideally, I think there should be another mechanism for fontifying
      buffers without "modifying" buffers, or redisplay should be
      smarter about updating the `*' in mode lines.  --gerd  */
-  XSETBUFFER (buffer, current_buffer);
-  window = Fget_buffer_window (buffer, Qt);
-  if (WINDOWP (window))
+  if (buffer_window_count (current_buffer))
     {
       ++update_mode_lines;
       current_buffer->prevent_redisplay_optimizations_p = 1;
@@ -1525,6 +1530,16 @@ This does not change the name of the visited file (if any).  */)
   return BVAR (current_buffer, name);
 }
 
+/* True if B can be used as 'other-than-BUFFER' buffer.  */
+
+static bool
+candidate_buffer (Lisp_Object b, Lisp_Object buffer)
+{
+  return (BUFFERP (b) && !EQ (b, buffer)
+          && BUFFER_LIVE_P (XBUFFER (b))
+          && !BUFFER_HIDDEN_P (XBUFFER (b)));
+}
+          
 DEFUN ("other-buffer", Fother_buffer, Sother_buffer, 0, 3, 0,
        doc: /* Return most recently selected buffer other than BUFFER.
 Buffers not visible in windows are preferred to visible buffers, unless
@@ -1538,23 +1553,15 @@ list first, followed by the list of all buffers.  If no other buffer
 exists, return the buffer `*scratch*' (creating it if necessary).  */)
   (register Lisp_Object buffer, Lisp_Object visible_ok, Lisp_Object frame)
 {
-  Lisp_Object tail, buf, pred;
-  Lisp_Object notsogood = Qnil;
-
-  if (NILP (frame))
-    frame = selected_frame;
+  struct frame *f = decode_any_frame (frame);
+  Lisp_Object tail = f->buffer_list, pred = f->buffer_predicate;
+  Lisp_Object buf, notsogood = Qnil;
 
-  CHECK_FRAME (frame);
-
-  pred = frame_buffer_predicate (frame);
   /* Consider buffers that have been seen in the frame first.  */
-  tail = XFRAME (frame)->buffer_list;
   for (; CONSP (tail); tail = XCDR (tail))
     {
       buf = XCAR (tail);
-      if (BUFFERP (buf) && !EQ (buf, buffer)
-          && BUFFER_LIVE_P (XBUFFER (buf))
-          && (SREF (BVAR (XBUFFER (buf), name), 0) != ' ')
+      if (candidate_buffer (buf, buffer)
           /* If the frame has a buffer_predicate, disregard buffers that
              don't fit the predicate.  */
           && (NILP (pred) || !NILP (call1 (pred, buf))))
@@ -1572,9 +1579,7 @@ exists, return the buffer `*scratch*' (creating it if necessary).  */)
   for (; CONSP (tail); tail = XCDR (tail))
     {
       buf = Fcdr (XCAR (tail));
-      if (BUFFERP (buf) && !EQ (buf, buffer)
-          && BUFFER_LIVE_P (XBUFFER (buf))
-          && (SREF (BVAR (XBUFFER (buf), name), 0) != ' ')
+      if (candidate_buffer (buf, buffer)
           /* If the frame has a buffer_predicate, disregard buffers that
              don't fit the predicate.  */
           && (NILP (pred) || !NILP (call1 (pred, buf))))
@@ -1610,13 +1615,10 @@ other_buffer_safely (Lisp_Object buffer)
 {
   Lisp_Object tail, buf;
 
-  tail = Vbuffer_alist;
-  for (; CONSP (tail); tail = XCDR (tail))
+  for (tail = Vbuffer_alist; CONSP (tail); tail = XCDR (tail))
     {
       buf = Fcdr (XCAR (tail));
-      if (BUFFERP (buf) && !EQ (buf, buffer)
-          && BUFFER_LIVE_P (XBUFFER (buf))
-          && (SREF (BVAR (XBUFFER (buf), name), 0) != ' '))
+      if (candidate_buffer (buf, buffer))
         return buf;
     }
 
@@ -1658,20 +1660,13 @@ No argument or nil as argument means do this for the current buffer.  */)
 void
 compact_buffer (struct buffer *buffer)
 {
-  /* Verify indirection counters.  */
-  if (buffer->base_buffer)
-    {
-      eassert (buffer->indirections == -1);
-      eassert (buffer->base_buffer->indirections > 0);
-    }
-  else
-    eassert (buffer->indirections >= 0);
+  BUFFER_CHECK_INDIRECTION (buffer);
 
   /* Skip dead buffers, indirect buffers and buffers
      which aren't changed since last compaction.  */
-  if (!NILP (buffer->INTERNAL_FIELD (name))
+  if (BUFFER_LIVE_P (buffer)
       && (buffer->base_buffer == NULL)
-      && (buffer->text->compact != buffer->text->modiff))
+      && (BUF_COMPACT (buffer) != BUF_MODIFF (buffer)))
     {
       /* If a buffer's undo list is Qt, that means that undo is
          turned off in that buffer.  Calling truncate_undo_list on
@@ -1684,19 +1679,15 @@ compact_buffer (struct buffer *buffer)
       if (!buffer->text->inhibit_shrinking)
         {
           /* If a buffer's gap size is more than 10% of the buffer
-             size, or larger than 2000 bytes, then shrink it
-             accordingly.  Keep a minimum size of 20 bytes.  */
-          int size = min (2000, max (20, (buffer->text->z_byte / 10)));
-
-          if (buffer->text->gap_size > size)
-            {
-              struct buffer *save_current = current_buffer;
-              current_buffer = buffer;
-              make_gap (-(buffer->text->gap_size - size));
-              current_buffer = save_current;
-            }
+             size, or larger than GAP_BYTES_DFL bytes, then shrink it
+             accordingly.  Keep a minimum size of GAP_BYTES_MIN bytes.  */
+          ptrdiff_t size = clip_to_bounds (GAP_BYTES_MIN,
+                                           BUF_Z_BYTE (buffer) / 10,
+                                           GAP_BYTES_DFL);
+          if (BUF_GAP_SIZE (buffer) > size)
+            make_gap_1 (buffer, -(BUF_GAP_SIZE (buffer) - size));
         }
-      buffer->text->compact = buffer->text->modiff;
+      BUF_COMPACT (buffer) = BUF_MODIFF (buffer);
     }
 }
 
@@ -1778,7 +1769,7 @@ cleaning up all windows currently displaying the buffer to be killed. */)
      since anything can happen within do_yes_or_no_p.  */
 
   /* Don't kill the minibuffer now current.  */
-  if (EQ (buffer, XWINDOW (minibuf_window)->buffer))
+  if (EQ (buffer, XWINDOW (minibuf_window)->contents))
     return Qnil;
 
   /* When we kill an ordinary buffer which shares it's buffer text
@@ -1829,7 +1820,7 @@ cleaning up all windows currently displaying the buffer to be killed. */)
   /* If the buffer now current is shown in the minibuffer and our buffer
      is the sole other buffer give up.  */
   XSETBUFFER (tem, current_buffer);
-  if (EQ (tem, XWINDOW (minibuf_window)->buffer)
+  if (EQ (tem, XWINDOW (minibuf_window)->contents)
       && EQ (buffer, Fother_buffer (buffer, Qnil, Qnil)))
     return Qnil;
 
@@ -1886,12 +1877,16 @@ cleaning up all windows currently displaying the buffer to be killed. */)
       /* Unchain all markers that belong to this indirect buffer.
          Don't unchain the markers that belong to the base buffer
          or its other indirect buffers.  */
-      for (m = BUF_MARKERS (b); m; )
+      struct Lisp_Marker **mp = &BUF_MARKERS (b);
+      while ((m = *mp))
         {
-          struct Lisp_Marker *next = m->next;
           if (m->buffer == b)
-            unchain_marker (m);
-          m = next;
+            {
+              m->buffer = NULL;
+              *mp = m->next;
+            }
+          else
+            mp = &m->next;
         }
     }
   else
@@ -1908,8 +1903,12 @@ cleaning up all windows currently displaying the buffer to be killed. */)
       BUF_MARKERS (b) = NULL;
       set_buffer_intervals (b, NULL);
 
-      /* Perhaps we should explicitly free the interval tree here... */
+      /* Perhaps we should explicitly free the interval tree here...  */
     }
+  /* Since we've unlinked the markers, the overlays can't be here any more
+     either.  */
+  b->overlays_before = NULL;
+  b->overlays_after = NULL;
 
   /* Reset the local variables, so that this buffer's local values
      won't be protected from GC.  They would be protected
@@ -1920,17 +1919,23 @@ cleaning up all windows currently displaying the buffer to be killed. */)
 
   bset_name (b, Qnil);
 
-  BLOCK_INPUT;
+  block_input ();
   if (b->base_buffer)
     {
       /* Notify our base buffer that we don't share the text anymore.  */
       eassert (b->indirections == -1);
       b->base_buffer->indirections--;
       eassert (b->base_buffer->indirections >= 0);
+      /* Make sure that we wasn't confused.  */
+      eassert (b->window_count == -1);
     }
   else
-    /* No one shares our buffer text, can free it.  */
-    free_buffer_text (b);
+    {
+      /* Make sure that no one shows us.  */
+      eassert (b->window_count == 0);
+      /* No one shares our buffer text, can free it.  */
+      free_buffer_text (b);
+    }
 
   if (b->newline_cache)
     {
@@ -1943,7 +1948,7 @@ cleaning up all windows currently displaying the buffer to be killed. */)
       b->width_run_cache = 0;
     }
   bset_width_table (b, Qnil);
-  UNBLOCK_INPUT;
+  unblock_input ();
   bset_undo_list (b, Qnil);
 
   /* Run buffer-list-update-hook.  */
@@ -2037,7 +2042,7 @@ DEFUN ("bury-buffer-internal", Fbury_buffer_internal, Sbury_buffer_internal,
 DEFUN ("set-buffer-major-mode", Fset_buffer_major_mode, Sset_buffer_major_mode, 1, 1, 0,
        doc: /* Set an appropriate major mode for BUFFER.
 For the *scratch* buffer, use `initial-major-mode', otherwise choose a mode
-according to `default-major-mode'.
+according to the default value of `major-mode'.
 Use this function before selecting the buffer, since it may need to inspect
 the current buffer's major mode.  */)
   (Lisp_Object buffer)
@@ -2102,6 +2107,8 @@ set_buffer_internal_1 (register struct buffer *b)
   if (current_buffer == b)
     return;
 
+  BUFFER_CHECK_INDIRECTION (b);
+
   old_buf = current_buffer;
   current_buffer = b;
   last_known_column_point = -1;   /* invalidate indentation cache */
@@ -2173,7 +2180,7 @@ set_buffer_temp (struct buffer *b)
 DEFUN ("set-buffer", Fset_buffer, Sset_buffer, 1, 1, 0,
        doc: /* Make buffer BUFFER-OR-NAME current for editing operations.
 BUFFER-OR-NAME may be a buffer or the name of an existing buffer.  See
-also `save-excursion' when you want to make a buffer current
+also `with-current-buffer' when you want to make a buffer current
 temporarily.  This function does not display the buffer, so its effect
 ends when the current command terminates.  Use `switch-to-buffer' or
 `pop-to-buffer' to switch buffers permanently.  */)
@@ -2387,8 +2394,9 @@ DEFUN ("buffer-swap-text", Fbuffer_swap_text, Sbuffer_swap_text,
            BUF_MARKERS(buf) should either be for `buf' or dead.  */
         eassert (!m->buffer);
   }
-  { /* Some of the C code expects that w->buffer == w->pointm->buffer.
-       So since we just swapped the markers between the two buffers, we need
+  { /* Some of the C code expects that both window markers of a
+       live window points to that window's buffer.  So since we
+       just swapped the markers between the two buffers, we need
        to undo the effect of this swap for window markers.  */
     Lisp_Object w = Fselected_window (), ws = Qnil;
     Lisp_Object buf1, buf2;
@@ -2398,12 +2406,19 @@ DEFUN ("buffer-swap-text", Fbuffer_swap_text, Sbuffer_swap_text,
       {
         ws = Fcons (w, ws);
         if (MARKERP (XWINDOW (w)->pointm)
-            && (EQ (XWINDOW (w)->buffer, buf1)
-                || EQ (XWINDOW (w)->buffer, buf2)))
+            && (EQ (XWINDOW (w)->contents, buf1)
+                || EQ (XWINDOW (w)->contents, buf2)))
           Fset_marker (XWINDOW (w)->pointm,
                        make_number
-                       (BUF_BEGV (XBUFFER (XWINDOW (w)->buffer))),
-                       XWINDOW (w)->buffer);
+                       (BUF_BEGV (XBUFFER (XWINDOW (w)->contents))),
+                       XWINDOW (w)->contents);
+        if (MARKERP (XWINDOW (w)->start)
+            && (EQ (XWINDOW (w)->contents, buf1)
+                || EQ (XWINDOW (w)->contents, buf2)))
+          Fset_marker (XWINDOW (w)->start,
+                       make_number
+                       (XBUFFER (XWINDOW (w)->contents)->last_window_start),
+                       XWINDOW (w)->contents);
         w = Fnext_window (w, Qt, Qt);
       }
   }
@@ -2461,7 +2476,7 @@ current buffer is cleared.  */)
     begv = BEGV, zv = ZV;
 
   if (narrowed)
-    Fwiden ();
+    error ("Changing multibyteness in a narrowed buffer");
 
   if (NILP (flag))
     {
@@ -2677,10 +2692,11 @@ current buffer is cleared.  */)
 
   UNGCPRO;
 
-  /* Changing the multibyteness of a buffer means that all windows
-     showing that buffer must be updated thoroughly.  */
   current_buffer->prevent_redisplay_optimizations_p = 1;
-  ++windows_or_buffers_changed;
+
+  /* If buffer is shown in a window, let redisplay consider other windows.  */
+  if (buffer_window_count (current_buffer))
+    ++windows_or_buffers_changed;
 
   /* Copy this buffer's new multibyte status
      into all of its indirect buffers.  */
@@ -3131,8 +3147,8 @@ compare_overlays (const void *v1, const void *v2)
      between "equal" overlays.  The result can still change between
      invocations of Emacs, but it won't change in the middle of
      `find_field' (bug#6830).  */
-  if (XHASH (s1->overlay) != XHASH (s2->overlay))
-    return XHASH (s1->overlay) < XHASH (s2->overlay) ? -1 : 1;
+  if (!EQ (s1->overlay, s2->overlay))
+    return XLI (s1->overlay) < XLI (s2->overlay) ? -1 : 1;
   return 0;
 }
 
@@ -3143,7 +3159,10 @@ ptrdiff_t
 sort_overlays (Lisp_Object *overlay_vec, ptrdiff_t noverlays, struct window *w)
 {
   ptrdiff_t i, j;
-  struct sortvec *sortvec = alloca (noverlays * sizeof *sortvec);
+  USE_SAFE_ALLOCA;
+  struct sortvec *sortvec;
+
+  SAFE_NALLOCA (sortvec, 1, noverlays);
 
   /* Put the valid and relevant overlays into sortvec.  */
 
@@ -3189,6 +3208,8 @@ sort_overlays (Lisp_Object *overlay_vec, ptrdiff_t noverlays, struct window *w)
 
   for (i = 0; i < noverlays; i++)
     overlay_vec[i] = sortvec[i].overlay;
+
+  SAFE_FREE ();
   return (noverlays);
 }
 
@@ -3686,7 +3707,6 @@ fix_start_end_in_overlays (register ptrdiff_t start, register ptrdiff_t end)
       beforep->next = current_buffer->overlays_before;
       set_buffer_overlays_before (current_buffer, before_list);
     }
-  recenter_overlay_lists (current_buffer, current_buffer->overlay_center);
 
   if (afterp)
     {
@@ -3844,17 +3864,16 @@ for the rear of the overlay advance when text is inserted there
   end = OVERLAY_END (overlay);
   if (OVERLAY_POSITION (end) < b->overlay_center)
     {
-      if (b->overlays_after)
-        XOVERLAY (overlay)->next = b->overlays_after;
+      eassert (b->overlays_after || (XOVERLAY (overlay)->next == NULL));
+      XOVERLAY (overlay)->next = b->overlays_after;
       set_buffer_overlays_after (b, XOVERLAY (overlay));
     }
   else
     {
-      if (b->overlays_before)
-        XOVERLAY (overlay)->next = b->overlays_before;
+      eassert (b->overlays_before || (XOVERLAY (overlay)->next == NULL));
+      XOVERLAY (overlay)->next = b->overlays_before;
       set_buffer_overlays_before (b, XOVERLAY (overlay));
     }
-
   /* This puts it in the right list, and in the right order.  */
   recenter_overlay_lists (b, b->overlay_center);
 
@@ -3878,17 +3897,17 @@ modify_overlay (struct buffer *buf, ptrdiff_t start, ptrdiff_t end)
 
   BUF_COMPUTE_UNCHANGED (buf, start, end);
 
-  /* If this is a buffer not in the selected window,
-     we must do other windows.  */
-  if (buf != XBUFFER (XWINDOW (selected_window)->buffer))
-    windows_or_buffers_changed = 1;
-  /* If multiple windows show this buffer, we must do other windows.  */
-  else if (buffer_shared > 1)
-    windows_or_buffers_changed = 1;
-  /* If we modify an overlay at the end of the buffer, we cannot
-     be sure that window end is still valid.  */
-  else if (end >= ZV && start <= ZV)
-    windows_or_buffers_changed = 1;
+  /* If BUF is visible, consider updating the display if ...  */
+  if (buffer_window_count (buf) > 0)
+    {
+      /* ... it's visible in other window than selected,  */
+      if (buf != XBUFFER (XWINDOW (selected_window)->contents))
+        windows_or_buffers_changed = 1;
+      /* ... or if we modify an overlay at the end of the buffer
+         and so we cannot be sure that window end is still valid.  */
+      else if (end >= ZV && start <= ZV)
+        windows_or_buffers_changed = 1;
+    }
 
   ++BUF_OVERLAY_MODIFF (buf);
 }
@@ -4138,7 +4157,7 @@ DEFUN ("overlays-at", Foverlays_at, Soverlays_at, 1, 1, 0,
   /* Put all the overlays we want in a vector in overlay_vec.
      Store the length in len.  */
   noverlays = overlays_at (XINT (pos), 1, &overlay_vec, &len,
-                           0, 0, 0);
+                           NULL, NULL, 0);
 
   /* Make a list of them all.  */
   result = Flist (noverlays, overlay_vec);
@@ -4567,27 +4586,7 @@ evaporate_overlays (ptrdiff_t pos)
   for (; CONSP (hit_list); hit_list = XCDR (hit_list))
     Fdelete_overlay (XCAR (hit_list));
 }
-
-/* Somebody has tried to store a value with an unacceptable type
-   in the slot with offset OFFSET.  */
-
-void
-buffer_slot_type_mismatch (Lisp_Object newval, int type)
-{
-  Lisp_Object predicate;
-
-  switch (type)
-    {
-    case_Lisp_Int:    predicate = Qintegerp; break;
-    case Lisp_String: predicate = Qstringp;  break;
-    case Lisp_Symbol: predicate = Qsymbolp;  break;
-    default: emacs_abort ();
-    }
-
-  wrong_type_argument (predicate, newval);
-}
 
-
 /***********************************************************************
                          Allocation with mmap
  ***********************************************************************/
@@ -5029,7 +5028,7 @@ alloc_buffer_text (struct buffer *b, ptrdiff_t nbytes)
 {
   void *p;
 
-  BLOCK_INPUT;
+  block_input ();
 #if defined USE_MMAP_FOR_BUFFERS
   p = mmap_alloc ((void **) &b->text->beg, nbytes);
 #elif defined REL_ALLOC
@@ -5040,12 +5039,12 @@ alloc_buffer_text (struct buffer *b, ptrdiff_t nbytes)
 
   if (p == NULL)
     {
-      UNBLOCK_INPUT;
+      unblock_input ();
       memory_full (nbytes);
     }
 
   b->text->beg = (unsigned char *) p;
-  UNBLOCK_INPUT;
+  unblock_input ();
 }
 
 /* Enlarge buffer B's text buffer by DELTA bytes.  DELTA < 0 means
@@ -5057,7 +5056,7 @@ enlarge_buffer_text (struct buffer *b, ptrdiff_t delta)
   void *p;
   ptrdiff_t nbytes = (BUF_Z_BYTE (b) - BUF_BEG_BYTE (b) + BUF_GAP_SIZE (b) + 1
                       + delta);
-  BLOCK_INPUT;
+  block_input ();
 #if defined USE_MMAP_FOR_BUFFERS
   p = mmap_realloc ((void **) &b->text->beg, nbytes);
 #elif defined REL_ALLOC
@@ -5068,12 +5067,12 @@ enlarge_buffer_text (struct buffer *b, ptrdiff_t delta)
 
   if (p == NULL)
     {
-      UNBLOCK_INPUT;
+      unblock_input ();
       memory_full (nbytes);
     }
 
   BUF_BEG_ADDR (b) = (unsigned char *) p;
-  UNBLOCK_INPUT;
+  unblock_input ();
 }
 
 
@@ -5082,7 +5081,7 @@ enlarge_buffer_text (struct buffer *b, ptrdiff_t delta)
 static void
 free_buffer_text (struct buffer *b)
 {
-  BLOCK_INPUT;
+  block_input ();
 
 #if defined USE_MMAP_FOR_BUFFERS
   mmap_free ((void **) &b->text->beg);
@@ -5093,7 +5092,7 @@ free_buffer_text (struct buffer *b)
 #endif
 
   BUF_BEG_ADDR (b) = NULL;
-  UNBLOCK_INPUT;
+  unblock_input ();
 }
 
 
@@ -5106,11 +5105,6 @@ void
 init_buffer_once (void)
 {
   int idx;
-  /* If you add, remove, or reorder Lisp_Objects in a struct buffer, make
-     sure that this is still correct.  Otherwise, mark_vectorlike may not
-     trace all Lisp_Objects in buffer_defaults and buffer_local_symbols.  */
-  const int pvecsize
-    = (offsetof (struct buffer, own_text) - header_size) / word_size;
 
   memset (buffer_permanent_local_flags, 0, sizeof buffer_permanent_local_flags);
 
@@ -5128,13 +5122,16 @@ init_buffer_once (void)
   /* No one will share the text with these buffers, but let's play it safe.  */
   buffer_defaults.indirections = 0;
   buffer_local_symbols.indirections = 0;
+  /* Likewise no one will display them.  */
+  buffer_defaults.window_count = 0;
+  buffer_local_symbols.window_count = 0;
   set_buffer_intervals (&buffer_defaults, NULL);
   set_buffer_intervals (&buffer_local_symbols, NULL);
   /* This is not strictly necessary, but let's make them initialized.  */
   bset_name (&buffer_defaults, build_pure_c_string (" *buffer-defaults*"));
   bset_name (&buffer_local_symbols, build_pure_c_string (" *buffer-local-symbols*"));
-  XSETPVECTYPESIZE (&buffer_defaults, PVEC_BUFFER, pvecsize);
-  XSETPVECTYPESIZE (&buffer_local_symbols, PVEC_BUFFER, pvecsize);
+  BUFFER_PVEC_INIT (&buffer_defaults);
+  BUFFER_PVEC_INIT (&buffer_local_symbols);
 
   /* Set up the default values of various buffer slots.  */
   /* Must do these before making the first buffer! */
@@ -5363,25 +5360,23 @@ init_buffer (void)
   free (pwd);
 }
 
-/* Similar to defvar_lisp but define a variable whose value is the Lisp
-   Object stored in the current buffer.  address is the address of the slot
-   in the buffer that is current now. */
-
-/* TYPE is nil for a general Lisp variable.
-   An integer specifies a type; then only Lisp values
-   with that type code are allowed (except that nil is allowed too).
-   LNAME is the Lisp-level variable name.
-   VNAME is the name of the buffer slot.
-   DOC is a dummy where you write the doc string as a comment.  */
-#define DEFVAR_PER_BUFFER(lname, vname, type, doc)                      \
-  do {                                                                  \
-    static struct Lisp_Buffer_Objfwd bo_fwd;                            \
-    defvar_per_buffer (&bo_fwd, lname, vname, type);                    \
+/* Similar to defvar_lisp but define a variable whose value is the
+   Lisp_Object stored in the current buffer.  LNAME is the Lisp-level
+   variable name.  VNAME is the name of the buffer slot.  PREDICATE
+   is nil for a general Lisp variable.  If PREDICATE is non-nil, then
+   only Lisp values that satisfies the PREDICATE are allowed (except
+   that nil is allowed too).  DOC is a dummy where you write the doc
+   string as a comment.  */
+
+#define DEFVAR_PER_BUFFER(lname, vname, predicate, doc)         \
+  do {                                                          \
+    static struct Lisp_Buffer_Objfwd bo_fwd;                    \
+    defvar_per_buffer (&bo_fwd, lname, vname, predicate);       \
   } while (0)
 
 static void
 defvar_per_buffer (struct Lisp_Buffer_Objfwd *bo_fwd, const char *namestring,
-                   Lisp_Object *address, Lisp_Object type)
+                   Lisp_Object *address, Lisp_Object predicate)
 {
   struct Lisp_Symbol *sym;
   int offset;
@@ -5391,7 +5386,7 @@ defvar_per_buffer (struct Lisp_Buffer_Objfwd *bo_fwd, const char *namestring,
 
   bo_fwd->type = Lisp_Fwd_Buffer_Obj;
   bo_fwd->offset = offset;
-  bo_fwd->slottype = type;
+  bo_fwd->predicate = predicate;
   sym->declared_special = 1;
   sym->redirect = SYMBOL_FORWARDED;
   {
@@ -5506,6 +5501,8 @@ This is the same as (default-value 'left-margin).  */);
   DEFVAR_BUFFER_DEFAULTS ("default-tab-width",
                           tab_width,
                           doc: /* Default value of `tab-width' for buffers that do not override it.
+NOTE: This controls the display width of a TAB character, and not
+the size of an indentation step.
 This is the same as (default-value 'tab-width).  */);
 
   DEFVAR_BUFFER_DEFAULTS ("default-case-fold-search",
@@ -5654,7 +5651,7 @@ Decimal digits after the % specify field width to which to pad.  */);
                           doc: /* Value of `major-mode' for new buffers.  */);
 
   DEFVAR_PER_BUFFER ("major-mode", &BVAR (current_buffer, major_mode),
-                     make_number (Lisp_Symbol),
+                     Qsymbolp,
                      doc: /* Symbol for current buffer's major mode.
 The default value (normally `fundamental-mode') affects new buffers.
 A value of nil means to use the current buffer's major mode, provided
@@ -5685,18 +5682,20 @@ Use the command `abbrev-mode' to change this variable.  */);
                      doc: /* Non-nil if searches and matches should ignore case.  */);
 
   DEFVAR_PER_BUFFER ("fill-column", &BVAR (current_buffer, fill_column),
-                     make_number (Lisp_Int0),
+                     Qintegerp,
                      doc: /* Column beyond which automatic line-wrapping should happen.
 Interactively, you can set the buffer local value using \\[set-fill-column].  */);
 
   DEFVAR_PER_BUFFER ("left-margin", &BVAR (current_buffer, left_margin),
-                     make_number (Lisp_Int0),
+                     Qintegerp,
                      doc: /* Column for the default `indent-line-function' to indent to.
 Linefeed indents to this column in Fundamental mode.  */);
 
   DEFVAR_PER_BUFFER ("tab-width", &BVAR (current_buffer, tab_width),
-                     make_number (Lisp_Int0),
+                     Qintegerp,
                      doc: /* Distance between tab stops (for display of tab characters), in columns.
+NOTE: This controls the display width of a TAB character, and not
+the size of an indentation step.
 This should be an integer greater than zero.  */);
 
   DEFVAR_PER_BUFFER ("ctl-arrow", &BVAR (current_buffer, ctl_arrow), Qnil,
@@ -5780,7 +5779,7 @@ visual lines rather than logical lines.  See the documentation of
 `visual-line-mode'.  */);
 
   DEFVAR_PER_BUFFER ("default-directory", &BVAR (current_buffer, directory),
-                     make_number (Lisp_String),
+                     Qstringp,
                      doc: /* Name of default directory of current buffer.  Should end with slash.
 To interactively change the default directory, use command `cd'.  */);
 
@@ -5793,18 +5792,18 @@ NOTE: This variable is not a hook;
 its value may not be a list of functions.  */);
 
   DEFVAR_PER_BUFFER ("buffer-file-name", &BVAR (current_buffer, filename),
-                     make_number (Lisp_String),
+                     Qstringp,
                      doc: /* Name of file visited in current buffer, or nil if not visiting a file.  */);
 
   DEFVAR_PER_BUFFER ("buffer-file-truename", &BVAR (current_buffer, file_truename),
-                     make_number (Lisp_String),
+                     Qstringp,
                      doc: /* Abbreviated truename of file visited in current buffer, or nil if none.
 The truename of a file is calculated by `file-truename'
 and then abbreviated with `abbreviate-file-name'.  */);
 
   DEFVAR_PER_BUFFER ("buffer-auto-save-file-name",
                      &BVAR (current_buffer, auto_save_file_name),
-                     make_number (Lisp_String),
+                     Qstringp,
                      doc: /* Name of file for auto-saving current buffer.
 If it is nil, that means don't auto-save this buffer.  */);
 
@@ -5816,7 +5815,7 @@ If it is nil, that means don't auto-save this buffer.  */);
 Backing up is done before the first time the file is saved.  */);
 
   DEFVAR_PER_BUFFER ("buffer-saved-size", &BVAR (current_buffer, save_length),
-                     make_number (Lisp_Int0),
+                     Qintegerp,
                      doc: /* Length of current buffer when last read in, saved or auto-saved.
 0 initially.
 -1 means auto-saving turned off until next real save.
@@ -5886,34 +5885,49 @@ In addition, a char-table has six extra slots to control the display of:
 See also the functions `display-table-slot' and `set-display-table-slot'.  */);
 
   DEFVAR_PER_BUFFER ("left-margin-width", &BVAR (current_buffer, left_margin_cols),
-                     Qnil,
+                     Qintegerp,
                      doc: /* Width of left marginal area for display of a buffer.
-A value of nil means no marginal area.  */);
+A value of nil means no marginal area.
+
+Setting this variable does not take effect until a new buffer is displayed
+in a window.  To make the change take effect, call `set-window-buffer'.  */);
 
   DEFVAR_PER_BUFFER ("right-margin-width", &BVAR (current_buffer, right_margin_cols),
-                     Qnil,
+                     Qintegerp,
                      doc: /* Width of right marginal area for display of a buffer.
-A value of nil means no marginal area.  */);
+A value of nil means no marginal area.
+
+Setting this variable does not take effect until a new buffer is displayed
+in a window.  To make the change take effect, call `set-window-buffer'.  */);
 
   DEFVAR_PER_BUFFER ("left-fringe-width", &BVAR (current_buffer, left_fringe_width),
-                     Qnil,
+                     Qintegerp,
                      doc: /* Width of this buffer's left fringe (in pixels).
 A value of 0 means no left fringe is shown in this buffer's window.
-A value of nil means to use the left fringe width from the window's frame.  */);
+A value of nil means to use the left fringe width from the window's frame.
+
+Setting this variable does not take effect until a new buffer is displayed
+in a window.  To make the change take effect, call `set-window-buffer'.  */);
 
   DEFVAR_PER_BUFFER ("right-fringe-width", &BVAR (current_buffer, right_fringe_width),
-                     Qnil,
+                     Qintegerp,
                      doc: /* Width of this buffer's right fringe (in pixels).
 A value of 0 means no right fringe is shown in this buffer's window.
-A value of nil means to use the right fringe width from the window's frame.  */);
+A value of nil means to use the right fringe width from the window's frame.
+
+Setting this variable does not take effect until a new buffer is displayed
+in a window.  To make the change take effect, call `set-window-buffer'.  */);
 
   DEFVAR_PER_BUFFER ("fringes-outside-margins", &BVAR (current_buffer, fringes_outside_margins),
                      Qnil,
                      doc: /* Non-nil means to display fringes outside display margins.
-A value of nil means to display fringes between margins and buffer text.  */);
+A value of nil means to display fringes between margins and buffer text.
+
+Setting this variable does not take effect until a new buffer is displayed
+in a window.  To make the change take effect, call `set-window-buffer'.  */);
 
   DEFVAR_PER_BUFFER ("scroll-bar-width", &BVAR (current_buffer, scroll_bar_width),
-                     Qnil,
+                     Qintegerp,
                      doc: /* Width of this buffer's scroll bars in pixels.
 A value of nil means to use the scroll bar width from the window's frame.  */);
 
@@ -5993,7 +6007,7 @@ BITMAP is the corresponding fringe bitmap shown for the logical
 cursor type.  */);
 
   DEFVAR_PER_BUFFER ("scroll-up-aggressively",
-                     &BVAR (current_buffer, scroll_up_aggressively), Qnil,
+                     &BVAR (current_buffer, scroll_up_aggressively), Qfloatp,
                      doc: /* How far to scroll windows upward.
 If you move point off the bottom, the window scrolls automatically.
 This variable controls how far it scrolls.  The value nil, the default,
@@ -6006,7 +6020,7 @@ window scrolls by a full window height.  Meaningful values are
 between 0.0 and 1.0, inclusive.  */);
 
   DEFVAR_PER_BUFFER ("scroll-down-aggressively",
-                     &BVAR (current_buffer, scroll_down_aggressively), Qnil,
+                     &BVAR (current_buffer, scroll_down_aggressively), Qfloatp,
                      doc: /* How far to scroll windows downward.
 If you move point off the top, the window scrolls automatically.
 This variable controls how far it scrolls.  The value nil, the default,
@@ -6018,10 +6032,6 @@ simple case that you moved off with C-b means scrolling just one line.
 window scrolls by a full window height.  Meaningful values are
 between 0.0 and 1.0, inclusive.  */);
 
-/*DEFVAR_LISP ("debug-check-symbol", &Vcheck_symbol,
-    "Don't ask.");
-*/
-
   DEFVAR_LISP ("before-change-functions", Vbefore_change_functions,
                doc: /* List of functions to call before each text change.
 Two arguments are passed to each function: the positions of
@@ -6160,7 +6170,7 @@ then characters with property value PROP are invisible,
 and they have an ellipsis as well if ELLIPSIS is non-nil.  */);
 
   DEFVAR_PER_BUFFER ("buffer-display-count",
-                     &BVAR (current_buffer, display_count), Qnil,
+                     &BVAR (current_buffer, display_count), Qintegerp,
                      doc: /* A number incremented each time this buffer is displayed in a window.
 The function `set-window-buffer' increments it.  */);
 
@@ -6204,22 +6214,22 @@ is a member of the list.  */);
                      doc: /* Cursor to use when this buffer is in the selected window.
 Values are interpreted as follows:
 
-  t               use the cursor specified for the frame
-  nil             don't display a cursor
-  box             display a filled box cursor
-  hollow          display a hollow box cursor
-  bar             display a vertical bar cursor with default width
-  (bar . WIDTH)   display a vertical bar cursor with width WIDTH
-  hbar            display a horizontal bar cursor with default height
+  t               use the cursor specified for the frame
+  nil             don't display a cursor
+  box             display a filled box cursor
+  hollow          display a hollow box cursor
+  bar             display a vertical bar cursor with default width
+  (bar . WIDTH)   display a vertical bar cursor with width WIDTH
+  hbar            display a horizontal bar cursor with default height
   (hbar . HEIGHT) display a horizontal bar cursor with height HEIGHT
-  ANYTHING ELSE   display a hollow box cursor
+  ANYTHING ELSE   display a hollow box cursor
 
 When the buffer is displayed in a non-selected window, the
 cursor's appearance is instead controlled by the variable
 `cursor-in-non-selected-windows'.  */);
 
   DEFVAR_PER_BUFFER ("line-spacing",
-                     &BVAR (current_buffer, extra_line_spacing), Qnil,
+                     &BVAR (current_buffer, extra_line_spacing), Qnumberp,
                      doc: /* Additional space to put between lines when displaying a buffer.
 The space is measured in pixels, and put below lines on graphic displays,
 see `display-graphic-p'.