Explicitly mark buffer_defaults and buffer_local_symbols.

* alloc.c (Fgarbage_collect): Mark buffer_defaults and
mark_local_symbols here.
(mark_object): If GC_CHECK_MARKED_OBJECTS, simplify checking
since special buffers aren't marked here any more.
(allocate_buffer): Chain new buffer with all_buffers here...
* buffer.c (Fget_buffer_create, Fmake_indirect_buffer): ...and
not here.
(Vbuffer_defaults, Vbuffer_local_symbols): Remove.
(syms_of_buffer): Remove staticpro of the above.
(init_buffer_once): Set names for buffer_defaults and
buffer_local_symbols.

3 files changed, 35 insertions, 32 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 2ca75d416af..a017ef7fdab 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,18 @@
+2012-09-06  Dmitry Antipov  <dmantipov@yandex.ru>
+
+        Explicitly mark buffer_defaults and buffer_local_symbols.
+        * alloc.c (Fgarbage_collect): Mark buffer_defaults and
+        mark_local_symbols here.
+        (mark_object): If GC_CHECK_MARKED_OBJECTS, simplify checking
+        since special buffers aren't marked here any more.
+        (allocate_buffer): Chain new buffer with all_buffers here...
+        * buffer.c (Fget_buffer_create, Fmake_indirect_buffer): ...and
+        not here.
+        (Vbuffer_defaults, Vbuffer_local_symbols): Remove.
+        (syms_of_buffer): Remove staticpro of the above.
+        (init_buffer_once): Set names for buffer_defaults and
+        buffer_local_symbols.
+
 2012-09-06  Paul Eggert  <eggert@cs.ucla.edu>
 
         Use bool for booleans in font-related modules.
diff --git a/src/alloc.c b/src/alloc.c
index aca0a82d1b5..1a9718bcb25 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -278,6 +278,7 @@ static void gc_sweep (void);
 static Lisp_Object make_pure_vector (ptrdiff_t);
 static void mark_glyph_matrix (struct glyph_matrix *);
 static void mark_face_cache (struct face_cache *);
+static void mark_buffer (struct buffer *);
 
 #if !defined REL_ALLOC || defined SYSTEM_MALLOC
 static void refill_memory_reserve (void);
@@ -3281,7 +3282,10 @@ allocate_buffer (void)
 
   XSETPVECTYPESIZE (b, PVEC_BUFFER, (offsetof (struct buffer, own_text)
                                      - header_size) / word_size);
-  /* Note that the fields of B are not initialized.  */
+  /* Put B on the chain of all buffers including killed ones.  */
+  b->header.next.buffer = all_buffers;
+  all_buffers = b;
+  /* Note that the rest fields of B are not initialized.  */
   return b;
 }
 
@@ -5473,6 +5477,9 @@ See Info node `(elisp)Garbage Collection'.  */)
 
   /* Mark all the special slots that serve as the roots of accessibility.  */
 
+  mark_buffer (&buffer_defaults);
+  mark_buffer (&buffer_local_symbols);
+
   for (i = 0; i < staticidx; i++)
     mark_object (*staticvec[i]);
 
@@ -5950,9 +5957,7 @@ mark_object (Lisp_Object arg)
 
 #ifdef GC_CHECK_MARKED_OBJECTS
         m = mem_find (po);
-        if (m == MEM_NIL && !SUBRP (obj)
-            && po != &buffer_defaults
-            && po != &buffer_local_symbols)
+        if (m == MEM_NIL && !SUBRP (obj))
           emacs_abort ();
 #endif /* GC_CHECK_MARKED_OBJECTS */
 
@@ -5969,15 +5974,14 @@ mark_object (Lisp_Object arg)
           {
           case PVEC_BUFFER:
 #ifdef GC_CHECK_MARKED_OBJECTS
-            if (po != &buffer_defaults && po != &buffer_local_symbols)
-              {
-                struct buffer *b;
-                FOR_EACH_BUFFER (b)
-                  if (b == po)
-                    break;
-                if (b == NULL)
-                  emacs_abort ();
-              }
+            {
+              struct buffer *b;
+              FOR_EACH_BUFFER (b)
+                if (b == po)
+                  break;
+              if (b == NULL)
+                emacs_abort ();
+            }
 #endif /* GC_CHECK_MARKED_OBJECTS */
             mark_buffer ((struct buffer *) ptr);
             break;
diff --git a/src/buffer.c b/src/buffer.c
index 7698b72a3c6..187277d663b 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -60,10 +60,6 @@ struct buffer *all_buffers;
 
 struct buffer alignas (GCALIGNMENT) buffer_defaults;
 
-/* A Lisp_Object pointer to the above, used for staticpro */
-
-static Lisp_Object Vbuffer_defaults;
-
 /* This structure marks which slots in a buffer have corresponding
    default values in buffer_defaults.
    Each such slot has a nonzero value in this structure.
@@ -87,9 +83,6 @@ struct buffer buffer_local_flags;
 
 struct buffer alignas (GCALIGNMENT) buffer_local_symbols;
 
-/* A Lisp_Object pointer to the above, used for staticpro */
-static Lisp_Object Vbuffer_local_symbols;
-
 /* Return the symbol of the per-buffer variable at offset OFFSET in
    the buffer structure.  */
 
@@ -595,10 +588,6 @@ even if it is dead.  The return value is never nil.  */)
   bset_width_table (b, Qnil);
   b->prevent_redisplay_optimizations_p = 1;
 
-  /* Put this on the chain of all buffers including killed ones.  */
-  b->header.next.buffer = all_buffers;
-  all_buffers = b;
-
   /* An ordinary buffer normally doesn't need markers
      to handle BEGV and ZV.  */
   bset_pt_marker (b, Qnil);
@@ -819,10 +808,6 @@ CLONE nil means the indirect buffer's state is reset to default values.  */)
   b->width_run_cache = 0;
   bset_width_table (b, Qnil);
 
-  /* Put this on the chain of all buffers including killed ones.  */
-  b->header.next.buffer = all_buffers;
-  all_buffers = b;
-
   name = Fcopy_sequence (name);
   set_string_intervals (name, NULL);
   bset_name (b, name);
@@ -5145,10 +5130,11 @@ init_buffer_once (void)
   buffer_local_symbols.indirections = 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);
-  XSETBUFFER (Vbuffer_defaults, &buffer_defaults);
   XSETPVECTYPESIZE (&buffer_local_symbols, PVEC_BUFFER, pvecsize);
-  XSETBUFFER (Vbuffer_local_symbols, &buffer_local_symbols);
 
   /* Set up the default values of various buffer slots.  */
   /* Must do these before making the first buffer! */
@@ -5430,8 +5416,6 @@ syms_of_buffer (void)
   last_overlay_modification_hooks
     = Fmake_vector (make_number (10), Qnil);
 
-  staticpro (&Vbuffer_defaults);
-  staticpro (&Vbuffer_local_symbols);
   staticpro (&Qfundamental_mode);
   staticpro (&Qmode_class);
   staticpro (&QSFundamental);