Hide implementation of `struct buffer'

	* composite.c (fill_gstring_header)
	(composition_compute_stop_pos, composition_adjust_point)
	(Ffind_composition_internal): Use B_.
	* intervals.c (set_point_both, get_local_map): Use B_.
	* callproc.c (Fcall_process, Fcall_process_region): Use B_.
	* process.c (get_process, list_processes_1, Fstart_process)
	(Fmake_serial_process, Fmake_network_process)
	(read_process_output, send_process, exec_sentinel)
	(status_notify, setup_process_coding_systems): Use B_.
	* bytecode.c (Fbyte_code): Use B_.
	* syntax.c (update_syntax_table, dec_bytepos, Fsyntax_table)
	(Fset_syntax_table, Fmodify_syntax_entry, skip_chars)
	(skip_syntaxes, scan_lists): Use B_.
	* lread.c (readchar, unreadchar, openp, readevalloop)
	(Feval_buffer, Feval_region): Use B_.
	* print.c (printchar, strout, print_string, PRINTDECLARE)
	(PRINTPREPARE, PRINTFINISH, temp_output_buffer_setup)
	(print_object): Use B_.
	* font.c (font_at): Use B_.
	* fns.c (Fbase64_encode_region, Fbase64_decode_region, Fmd5): Use
	B_.
	* callint.c (check_mark, Fcall_interactively): Use B_.
	* editfns.c (region_limit, Fmark_marker, save_excursion_save)
	(save_excursion_restore, Fprevious_char, Fchar_before)
	(general_insert_function, Finsert_char, Finsert_byte)
	(make_buffer_string_both, Finsert_buffer_substring)
	(Fcompare_buffer_substrings, subst_char_in_region_unwind)
	(subst_char_in_region_unwind_1, Fsubst_char_in_region)
	(Ftranslate_region_internal, save_restriction_restore)
	(Fchar_equal): Use B_.
	* data.c (swap_in_symval_forwarding, set_internal)
	(Fmake_local_variable, Fkill_local_variable, Flocal_variable_p):
	Use B_.
	* undo.c (record_point, record_insert, record_delete)
	(record_marker_adjustment, record_first_change)
	(record_property_change, Fundo_boundary, truncate_undo_list)
	(Fprimitive_undo): Use B_.
	* search.c (compile_pattern_1, compile_pattern, looking_at_1)
	(string_match_1, fast_looking_at, newline_cache_on_off)
	(search_command, search_buffer, simple_search, boyer_moore)
	(Freplace_match): Use B_.
	* indent.c (buffer_display_table, recompute_width_table)
	(width_run_cache_on_off, current_column, scan_for_column)
	(Findent_to, position_indentation, compute_motion, vmotion): Use
	B_.
	* casefiddle.c (casify_object, casify_region): Use B_.
	* casetab.c (Fcurrent_case_table, set_case_table): Use B_.
	* cmds.c (Fself_insert_command, internal_self_insert): Use B_.
	* fileio.c (Fexpand_file_name, Ffile_directory_p)
	(Ffile_regular_p, Ffile_selinux_context)
	(Fset_file_selinux_context, Ffile_modes, Fset_file_modes)
	(Fset_file_times, Ffile_newer_than_file_p, decide_coding_unwind)
	(Finsert_file_contents, choose_write_coding_system)
	(Fwrite_region, build_annotations, Fverify_visited_file_modtime)
	(Fset_visited_file_modtime, auto_save_error, auto_save_1)
	(Fdo_auto_save, Fset_buffer_auto_saved): Use B_.
	* minibuf.c (read_minibuf, get_minibuffer, Fread_buffer): Use B_.
	* marker.c (Fmarker_buffer, Fset_marker, set_marker_restricted)
	(set_marker_both, set_marker_restricted_both, unchain_marker): Use
	B_.
	* insdel.c (check_markers, insert_char, insert_1_both)
	(insert_from_string_1, insert_from_gap, insert_from_buffer_1)
	(adjust_after_replace, replace_range, del_range_2)
	(modify_region, prepare_to_modify_buffer)
	(Fcombine_after_change_execute): Use B_.
	* filelock.c (unlock_all_files, Flock_buffer, Funlock_buffer)
	(unlock_buffer): Use B_.
	* keymap.c (Flocal_key_binding, Fuse_local_map)
	(Fcurrent_local_map, push_key_description)
	(Fdescribe_buffer_bindings): Use B_.
	* keyboard.c (command_loop_1, read_char_minibuf_menu_prompt)
	(read_key_sequence): Use B_.
	* fringe.c (get_logical_cursor_bitmap)
	(get_logical_fringe_bitmap, update_window_fringes): Use B_.
	* xfns.c (x_create_tip_frame, Fx_show_tip): Use B_.
	* xfaces.c (compute_char_face): Use B_.
	* character.c (chars_in_text, Fget_byte): Use B_.
	* category.c (check_category_table, Fcategory_table)
	(Fset_category_table, char_category_set): Use B_.
	* coding.c (decode_coding, encode_coding)
	(make_conversion_work_buffer, decode_coding_gap)
	(decode_coding_object, encode_coding_object)
	(Fdetect_coding_region, Ffind_coding_systems_region_internal)
	(Funencodable_char_position, Fcheck_coding_systems_region): Use
	B_.
	* charset.c (Ffind_charset_region): Use B_.
	* window.c (window_display_table, unshow_buffer, window_loop)
	(window_min_size_2, set_window_buffer, Fset_window_buffer)
	(select_window, Fforce_window_update, temp_output_buffer_show)
	(Fset_window_configuration, save_window_save): Use B_.
	* xdisp.c (pos_visible_p, init_iterator, reseat_1)
	(message_dolog, update_echo_area, ensure_echo_area_buffers)
	(with_echo_area_buffer, setup_echo_area_for_printing)
	(set_message_1, update_menu_bar, update_tool_bar)
	(text_outside_line_unchanged_p, redisplay_internal)
	(try_scrolling, try_cursor_movement, redisplay_window)
	(try_window_reusing_current_matrix, row_containing_pos)
	(try_window_id, get_overlay_arrow_glyph_row, display_line)
	(Fcurrent_bidi_paragraph_direction, display_mode_lines)
	(decode_mode_spec_coding, decode_mode_spec, display_count_lines)
	(get_window_cursor_type, note_mouse_highlight): Use B_.
	* frame.c (make_frame_visible_1): Use B_.
	* dispnew.c (Fframe_or_buffer_changed_p): Use B_.
	* dispextern.h (WINDOW_WANTS_HEADER_LINE_P)
	(WINDOW_WANTS_MODELINE_P): Use B_.
	* syntax.h (Vstandard_syntax_table): Update.
	(CURRENT_SYNTAX_TABLE, SETUP_BUFFER_SYNTAX_TABLE): Use B_.
	* intervals.h (TEXT_PROP_MEANS_INVISIBLE): Update.
	(TEXT_PROP_MEANS_INVISIBLE): Use B_.
	* character.h (FETCH_CHAR_ADVANCE): Update.
	(INC_BOTH, ASCII_CHAR_WIDTH, DEC_BOTH): Use B_.
	* category.h (Vstandard_category_table): Update.
	* lisp.h (DEFVAR_BUFFER_DEFAULTS): Update for change to field
	names.
	(DOWNCASE_TABLE, UPCASE_TABLE): Use B_.
	* buffer.c (swapfield_): New macro.
	(Fbuffer_swap_text): Use swapfield_ where appropriate.
	(Fbuffer_live_p, Fget_file_buffer, get_truename_buffer)
	(Fget_buffer_create, clone_per_buffer_values)
	(Fmake_indirect_buffer, reset_buffer)
	(reset_buffer_local_variables, Fbuffer_name, Fbuffer_file_name)
	(Fbuffer_local_value, buffer_lisp_local_variables)
	(Fset_buffer_modified_p, Frestore_buffer_modified_p)
	(Frename_buffer, Fother_buffer, Fbuffer_enable_undo)
	(Fkill_buffer, Fset_buffer_major_mode, set_buffer_internal_1)
	(set_buffer_temp, Fset_buffer, set_buffer_if_live)
	(Fbarf_if_buffer_read_only, Fbury_buffer, Ferase_buffer)
	(Fbuffer_swap_text, Fset_buffer_multibyte)
	(swap_out_buffer_local_variables, record_overlay_string)
	(overlay_strings, init_buffer_once, init_buffer, syms_of_buffer):
	Use B_.
	* buffer.h (struct buffer): Rename all Lisp_Object fields.
	(BUFFER_INTERNAL_FIELD, B_): New macro.
	(FETCH_CHAR, FETCH_CHAR_AS_MULTIBYTE): Use B_.

1 files changed, 80 insertions, 71 deletions

diff --git a/src/buffer.h b/src/buffer.h
index 31f96040b2d..36cb5fe9dda 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -321,7 +321,7 @@ while (0)
 /* Return character at byte position POS.  */
 
 #define FETCH_CHAR(pos)                                 \
-  (!NILP (current_buffer->enable_multibyte_characters)  \
+  (!NILP (B_ (current_buffer, enable_multibyte_characters))     \
    ? FETCH_MULTIBYTE_CHAR ((pos))                       \
    : FETCH_BYTE ((pos)))
 
@@ -346,7 +346,7 @@ extern unsigned char *_fetch_multibyte_char_p;
    multibyte.  */
 
 #define FETCH_CHAR_AS_MULTIBYTE(pos)                    \
-  (!NILP (current_buffer->enable_multibyte_characters)  \
+  (!NILP (B_ (current_buffer, enable_multibyte_characters))     \
    ? FETCH_MULTIBYTE_CHAR ((pos))                       \
    : UNIBYTE_TO_CHAR (FETCH_BYTE ((pos))))
 
@@ -464,6 +464,15 @@ struct buffer_text
     int inhibit_shrinking;
   };
 
+/* Lisp fields in struct buffer are hidden from most code and accessed
+   via the B_ macro, below.  Only select pieces of code, like the GC,
+   are allowed to use BUFFER_INTERNAL_FIELD.  */
+#define BUFFER_INTERNAL_FIELD(field) field ## _
+
+/* Most code should use this macro to access Lisp fields in struct
+   buffer.  */
+#define B_(buf, field) ((buf)->BUFFER_INTERNAL_FIELD (field))
+
 /* This is the structure that the buffer Lisp object points to.  */
 
 struct buffer
@@ -587,138 +596,138 @@ struct buffer
      because local variables have to be right in the  struct buffer.
      So we copy it around in set_buffer_internal.
      This comes before `name' because it is marked in a special way.  */
-  Lisp_Object undo_list;
+  Lisp_Object BUFFER_INTERNAL_FIELD (undo_list);
 
   /* The name of this buffer.  */
-  Lisp_Object name;
+  Lisp_Object BUFFER_INTERNAL_FIELD (name);
 
   /* The name of the file visited in this buffer, or nil.  */
-  Lisp_Object filename;
+  Lisp_Object BUFFER_INTERNAL_FIELD (filename);
   /* Dir for expanding relative file names.  */
-  Lisp_Object directory;
+  Lisp_Object BUFFER_INTERNAL_FIELD (directory);
   /* True if this buffer has been backed up (if you write to the
      visited file and it hasn't been backed up, then a backup will
      be made).  */
   /* This isn't really used by the C code, so could be deleted.  */
-  Lisp_Object backed_up;
+  Lisp_Object BUFFER_INTERNAL_FIELD (backed_up);
   /* Length of file when last read or saved.
      -1 means auto saving turned off because buffer shrank a lot.
      -2 means don't turn off auto saving if buffer shrinks.
        (That value is used with buffer-swap-text.)
      This is not in the  struct buffer_text
      because it's not used in indirect buffers at all.  */
-  Lisp_Object save_length;
+  Lisp_Object BUFFER_INTERNAL_FIELD (save_length);
   /* File name used for auto-saving this buffer.
      This is not in the  struct buffer_text
      because it's not used in indirect buffers at all.  */
-  Lisp_Object auto_save_file_name;
+  Lisp_Object BUFFER_INTERNAL_FIELD (auto_save_file_name);
 
   /* Non-nil if buffer read-only.  */
-  Lisp_Object read_only;
+  Lisp_Object BUFFER_INTERNAL_FIELD (read_only);
   /* "The mark".  This is a marker which may
      point into this buffer or may point nowhere.  */
-  Lisp_Object mark;
+  Lisp_Object BUFFER_INTERNAL_FIELD (mark);
 
   /* Alist of elements (SYMBOL . VALUE-IN-THIS-BUFFER) for all
      per-buffer variables of this buffer.  For locally unbound
      symbols, just the symbol appears as the element.  */
-  Lisp_Object local_var_alist;
+  Lisp_Object BUFFER_INTERNAL_FIELD (local_var_alist);
 
   /* Symbol naming major mode (eg, lisp-mode).  */
-  Lisp_Object major_mode;
+  Lisp_Object BUFFER_INTERNAL_FIELD (major_mode);
   /* Pretty name of major mode (eg, "Lisp"). */
-  Lisp_Object mode_name;
+  Lisp_Object BUFFER_INTERNAL_FIELD (mode_name);
   /* Mode line element that controls format of mode line.  */
-  Lisp_Object mode_line_format;
+  Lisp_Object BUFFER_INTERNAL_FIELD (mode_line_format);
 
   /* Analogous to mode_line_format for the line displayed at the top
      of windows.  Nil means don't display that line.  */
-  Lisp_Object header_line_format;
+  Lisp_Object BUFFER_INTERNAL_FIELD (header_line_format);
 
   /* Keys that are bound local to this buffer.  */
-  Lisp_Object keymap;
+  Lisp_Object BUFFER_INTERNAL_FIELD (keymap);
   /* This buffer's local abbrev table.  */
-  Lisp_Object abbrev_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (abbrev_table);
   /* This buffer's syntax table.  */
-  Lisp_Object syntax_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (syntax_table);
   /* This buffer's category table.  */
-  Lisp_Object category_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (category_table);
 
   /* Values of several buffer-local variables.  */
   /* tab-width is buffer-local so that redisplay can find it
      in buffers that are not current.  */
-  Lisp_Object case_fold_search;
-  Lisp_Object tab_width;
-  Lisp_Object fill_column;
-  Lisp_Object left_margin;
+  Lisp_Object BUFFER_INTERNAL_FIELD (case_fold_search);
+  Lisp_Object BUFFER_INTERNAL_FIELD (tab_width);
+  Lisp_Object BUFFER_INTERNAL_FIELD (fill_column);
+  Lisp_Object BUFFER_INTERNAL_FIELD (left_margin);
   /* Function to call when insert space past fill column.  */
-  Lisp_Object auto_fill_function;
+  Lisp_Object BUFFER_INTERNAL_FIELD (auto_fill_function);
   /* nil: text, t: binary.
      This value is meaningful only on certain operating systems.  */
   /* Actually, we don't need this flag any more because end-of-line
      is handled correctly according to the buffer-file-coding-system
      of the buffer.  Just keeping it for backward compatibility.  */
-  Lisp_Object buffer_file_type;
+  Lisp_Object BUFFER_INTERNAL_FIELD (buffer_file_type);
 
   /* Case table for case-conversion in this buffer.
      This char-table maps each char into its lower-case version.  */
-  Lisp_Object downcase_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (downcase_table);
   /* Char-table mapping each char to its upper-case version.  */
-  Lisp_Object upcase_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (upcase_table);
   /* Char-table for conversion for case-folding search.  */
-  Lisp_Object case_canon_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (case_canon_table);
   /* Char-table of equivalences for case-folding search.  */
-  Lisp_Object case_eqv_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (case_eqv_table);
 
   /* Non-nil means do not display continuation lines.  */
-  Lisp_Object truncate_lines;
+  Lisp_Object BUFFER_INTERNAL_FIELD (truncate_lines);
   /* Non-nil means to use word wrapping when displaying continuation lines.  */
-  Lisp_Object word_wrap;
+  Lisp_Object BUFFER_INTERNAL_FIELD (word_wrap);
   /* Non-nil means display ctl chars with uparrow.  */
-  Lisp_Object ctl_arrow;
+  Lisp_Object BUFFER_INTERNAL_FIELD (ctl_arrow);
   /* Non-nil means reorder bidirectional text for display in the
      visual order.  */
-  Lisp_Object bidi_display_reordering;
+  Lisp_Object BUFFER_INTERNAL_FIELD (bidi_display_reordering);
   /* If non-nil, specifies which direction of text to force in all the
      paragraphs of the buffer.  Nil means determine paragraph
      direction dynamically for each paragraph.  */
-  Lisp_Object bidi_paragraph_direction;
+  Lisp_Object BUFFER_INTERNAL_FIELD (bidi_paragraph_direction);
   /* Non-nil means do selective display;
      see doc string in syms_of_buffer (buffer.c) for details.  */
-  Lisp_Object selective_display;
+  Lisp_Object BUFFER_INTERNAL_FIELD (selective_display);
 #ifndef old
   /* Non-nil means show ... at end of line followed by invisible lines.  */
-  Lisp_Object selective_display_ellipses;
+  Lisp_Object BUFFER_INTERNAL_FIELD (selective_display_ellipses);
 #endif
   /* Alist of (FUNCTION . STRING) for each minor mode enabled in buffer.  */
-  Lisp_Object minor_modes;
+  Lisp_Object BUFFER_INTERNAL_FIELD (minor_modes);
   /* t if "self-insertion" should overwrite; `binary' if it should also
      overwrite newlines and tabs - for editing executables and the like.  */
-  Lisp_Object overwrite_mode;
+  Lisp_Object BUFFER_INTERNAL_FIELD (overwrite_mode);
   /* non-nil means abbrev mode is on.  Expand abbrevs automatically.  */
-  Lisp_Object abbrev_mode;
+  Lisp_Object BUFFER_INTERNAL_FIELD (abbrev_mode);
   /* Display table to use for text in this buffer.  */
-  Lisp_Object display_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (display_table);
   /* t means the mark and region are currently active.  */
-  Lisp_Object mark_active;
+  Lisp_Object BUFFER_INTERNAL_FIELD (mark_active);
 
   /* Non-nil means the buffer contents are regarded as multi-byte
      form of characters, not a binary code.  */
-  Lisp_Object enable_multibyte_characters;
+  Lisp_Object BUFFER_INTERNAL_FIELD (enable_multibyte_characters);
 
   /* Coding system to be used for encoding the buffer contents on
      saving.  */
-  Lisp_Object buffer_file_coding_system;
+  Lisp_Object BUFFER_INTERNAL_FIELD (buffer_file_coding_system);
 
   /* List of symbols naming the file format used for visited file.  */
-  Lisp_Object file_format;
+  Lisp_Object BUFFER_INTERNAL_FIELD (file_format);
 
   /* List of symbols naming the file format used for auto-save file.  */
-  Lisp_Object auto_save_file_format;
+  Lisp_Object BUFFER_INTERNAL_FIELD (auto_save_file_format);
 
   /* True if the newline position cache and width run cache are
      enabled.  See search.c and indent.c.  */
-  Lisp_Object cache_long_line_scans;
+  Lisp_Object BUFFER_INTERNAL_FIELD (cache_long_line_scans);
 
   /* If the width run cache is enabled, this table contains the
      character widths width_run_cache (see above) assumes.  When we
@@ -726,99 +735,99 @@ struct buffer
      current display table to see whether the display table has
      affected the widths of any characters.  If it has, we
      invalidate the width run cache, and re-initialize width_table.  */
-  Lisp_Object width_table;
+  Lisp_Object BUFFER_INTERNAL_FIELD (width_table);
 
   /* In an indirect buffer, or a buffer that is the base of an
      indirect buffer, this holds a marker that records
      PT for this buffer when the buffer is not current.  */
-  Lisp_Object pt_marker;
+  Lisp_Object BUFFER_INTERNAL_FIELD (pt_marker);
 
   /* In an indirect buffer, or a buffer that is the base of an
      indirect buffer, this holds a marker that records
      BEGV for this buffer when the buffer is not current.  */
-  Lisp_Object begv_marker;
+  Lisp_Object BUFFER_INTERNAL_FIELD (begv_marker);
 
   /* In an indirect buffer, or a buffer that is the base of an
      indirect buffer, this holds a marker that records
      ZV for this buffer when the buffer is not current.  */
-  Lisp_Object zv_marker;
+  Lisp_Object BUFFER_INTERNAL_FIELD (zv_marker);
 
   /* This holds the point value before the last scroll operation.
      Explicitly setting point sets this to nil.  */
-  Lisp_Object point_before_scroll;
+  Lisp_Object BUFFER_INTERNAL_FIELD (point_before_scroll);
 
   /* Truename of the visited file, or nil.  */
-  Lisp_Object file_truename;
+  Lisp_Object BUFFER_INTERNAL_FIELD (file_truename);
 
   /* Invisibility spec of this buffer.
      t => any non-nil `invisible' property means invisible.
      A list => `invisible' property means invisible
      if it is memq in that list.  */
-  Lisp_Object invisibility_spec;
+  Lisp_Object BUFFER_INTERNAL_FIELD (invisibility_spec);
 
   /* This is the last window that was selected with this buffer in it,
      or nil if that window no longer displays this buffer.  */
-  Lisp_Object last_selected_window;
+  Lisp_Object BUFFER_INTERNAL_FIELD (last_selected_window);
 
   /* Incremented each time the buffer is displayed in a window.  */
-  Lisp_Object display_count;
+  Lisp_Object BUFFER_INTERNAL_FIELD (display_count);
 
   /* Widths of left and right marginal areas for windows displaying
      this buffer.  */
-  Lisp_Object left_margin_cols, right_margin_cols;
+  Lisp_Object BUFFER_INTERNAL_FIELD (left_margin_cols), BUFFER_INTERNAL_FIELD (right_margin_cols);
 
   /* Widths of left and right fringe areas for windows displaying
      this buffer.  */
-  Lisp_Object left_fringe_width, right_fringe_width;
+  Lisp_Object BUFFER_INTERNAL_FIELD (left_fringe_width), BUFFER_INTERNAL_FIELD (right_fringe_width);
 
   /* Non-nil means fringes are drawn outside display margins;
      othersize draw them between margin areas and text.  */
-  Lisp_Object fringes_outside_margins;
+  Lisp_Object BUFFER_INTERNAL_FIELD (fringes_outside_margins);
 
   /* Width and type of scroll bar areas for windows displaying
      this buffer.  */
-  Lisp_Object scroll_bar_width, vertical_scroll_bar_type;
+  Lisp_Object BUFFER_INTERNAL_FIELD (scroll_bar_width), BUFFER_INTERNAL_FIELD (vertical_scroll_bar_type);
 
   /* Non-nil means indicate lines not displaying text (in a style
      like vi).  */
-  Lisp_Object indicate_empty_lines;
+  Lisp_Object BUFFER_INTERNAL_FIELD (indicate_empty_lines);
 
   /* Non-nil means indicate buffer boundaries and scrolling.  */
-  Lisp_Object indicate_buffer_boundaries;
+  Lisp_Object BUFFER_INTERNAL_FIELD (indicate_buffer_boundaries);
 
   /* Logical to physical fringe bitmap mappings.  */
-  Lisp_Object fringe_indicator_alist;
+  Lisp_Object BUFFER_INTERNAL_FIELD (fringe_indicator_alist);
 
   /* Logical to physical cursor bitmap mappings.  */
-  Lisp_Object fringe_cursor_alist;
+  Lisp_Object BUFFER_INTERNAL_FIELD (fringe_cursor_alist);
 
   /* Time stamp updated each time this buffer is displayed in a window.  */
-  Lisp_Object display_time;
+  Lisp_Object BUFFER_INTERNAL_FIELD (display_time);
 
   /* If scrolling the display because point is below the bottom of a
      window showing this buffer, try to choose a window start so
      that point ends up this number of lines from the top of the
      window.  Nil means that scrolling method isn't used.  */
-  Lisp_Object scroll_up_aggressively;
+  Lisp_Object BUFFER_INTERNAL_FIELD (scroll_up_aggressively);
 
   /* If scrolling the display because point is above the top of a
      window showing this buffer, try to choose a window start so
      that point ends up this number of lines from the bottom of the
      window.  Nil means that scrolling method isn't used.  */
-  Lisp_Object scroll_down_aggressively;
+  Lisp_Object BUFFER_INTERNAL_FIELD (scroll_down_aggressively);
 
   /* Desired cursor type in this buffer.  See the doc string of
      per-buffer variable `cursor-type'.  */
-  Lisp_Object cursor_type;
+  Lisp_Object BUFFER_INTERNAL_FIELD (cursor_type);
 
   /* An integer > 0 means put that number of pixels below text lines
      in the display of this buffer.  */
-  Lisp_Object extra_line_spacing;
+  Lisp_Object BUFFER_INTERNAL_FIELD (extra_line_spacing);
 
   /* *Cursor type to display in non-selected windows.
      t means to use hollow box cursor.
      See `cursor-type' for other values.  */
-  Lisp_Object cursor_in_non_selected_windows;
+  Lisp_Object BUFFER_INTERNAL_FIELD (cursor_in_non_selected_windows);
 };
 
 
@@ -942,7 +951,7 @@ extern int last_per_buffer_idx;
    from the start of a buffer structure.  */
 
 #define PER_BUFFER_VAR_OFFSET(VAR) \
-  offsetof (struct buffer, VAR)
+  offsetof (struct buffer, BUFFER_INTERNAL_FIELD (VAR))
 
 /* Return the index of buffer-local variable VAR.  Each per-buffer
    variable has an index > 0 associated with it, except when it always