[Emacs-diffs] /srv/bzr/emacs/trunk r105000: Merge: Remove unportable assumption about struct layout (Bug#8884).

[Paul Eggert]

------------------------------------------------------------
revno: 105000 [merge]
fixes bug(s): http://debbugs.gnu.org/8884
committer: Paul Eggert <address@hidden>
branch nick: trunk
timestamp: Wed 2011-07-06 14:56:44 -0700
message:
  Merge: Remove unportable assumption about struct layout (Bug#8884).
  
  * buffer.c (clone_per_buffer_values): Don't assume that
  sizeof (struct buffer) is a multiple of sizeof (Lisp_Object).
  This isn't true in general, and it's particularly not true
  if Emacs is configured with --with-wide-int.
  * buffer.h (FIRST_FIELD_PER_BUFFER, LAST_FIELD_PER_BUFFER):
  New macros, used in the buffer.c change.
modified:
  src/ChangeLog
  src/buffer.c
  src/buffer.h

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2011-07-05 09:51:56 +0000
+++ b/src/ChangeLog     2011-07-06 21:53:56 +0000
@@ -1,3 +1,13 @@
+2011-07-06  Paul Eggert  <address@hidden>
+
+       Remove unportable assumption about struct layout (Bug#8884).
+       * buffer.c (clone_per_buffer_values): Don't assume that
+       sizeof (struct buffer) is a multiple of sizeof (Lisp_Object).
+       This isn't true in general, and it's particularly not true
+       if Emacs is configured with --with-wide-int.
+       * buffer.h (FIRST_FIELD_PER_BUFFER, LAST_FIELD_PER_BUFFER):
+       New macros, used in the buffer.c change.
+
 2011-07-05  Jan Djärv  <address@hidden>
 
        * xsettings.c: Use both GConf and GSettings if both are available.

=== modified file 'src/buffer.c'
--- a/src/buffer.c      2011-07-04 15:32:22 +0000
+++ b/src/buffer.c      2011-07-06 21:53:56 +0000
@@ -471,8 +471,8 @@
 
   /* buffer-local Lisp variables start at `undo_list',
      tho only the ones from `name' on are GC'd normally.  */
-  for (offset = PER_BUFFER_VAR_OFFSET (undo_list);
-       offset < sizeof *to;
+  for (offset = PER_BUFFER_VAR_OFFSET (FIRST_FIELD_PER_BUFFER);
+       offset <= PER_BUFFER_VAR_OFFSET (LAST_FIELD_PER_BUFFER);
        offset += sizeof (Lisp_Object))
     {
       Lisp_Object obj;

=== modified file 'src/buffer.h'
--- a/src/buffer.h      2011-06-21 21:32:10 +0000
+++ b/src/buffer.h      2011-07-06 21:53:56 +0000
@@ -612,6 +612,7 @@
   /* Everything from here down must be a Lisp_Object.  */
   /* buffer-local Lisp variables start at `undo_list',
      tho only the ones from `name' on are GC'd normally.  */
+  #define FIRST_FIELD_PER_BUFFER undo_list
 
   /* Changes in the buffer are recorded here for undo.
      t means don't record anything.
@@ -846,6 +847,9 @@
      t means to use hollow box cursor.
      See `cursor-type' for other values.  */
   Lisp_Object BUFFER_INTERNAL_FIELD (cursor_in_non_selected_windows);
+
+  /* This must be the last field in the above list.  */
+  #define LAST_FIELD_PER_BUFFER cursor_in_non_selected_windows
 };