Generalize common compile-time constants.

* lisp.h (header_size, bool_header_size, word_size): Now here.
(struct Lisp_Vector): Add comment.
(struct Lisp_Bool_Vector): Move up to define handy constants.
(VECSIZE, PSEUDOVECSIZE): Simplify.
(SAFE_ALLOCA_LISP): Use new constant.  Adjust indentation.
* buffer.c, buffer.h, bytecode.c, callint.c, eval.c, fns.c:
* font.c, fontset.c, keyboard.c, keymap.c, macros.c, menu.c:
* msdos.c, w32menu.c, w32term.h, window.c, xdisp.c, xfaces.c:
* xfont.c, xmenu.c: Use word_size where appropriate.

1 files changed, 3 insertions, 11 deletions

diff --git a/src/alloc.c b/src/alloc.c
index 3939e704978..7d1ff7625f2 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -155,7 +155,7 @@ static pthread_mutex_t alloc_mutex;
 
 /* Default value of gc_cons_threshold (see below).  */
 
-#define GC_DEFAULT_THRESHOLD (100000 * sizeof (Lisp_Object))
+#define GC_DEFAULT_THRESHOLD (100000 * word_size)
 
 /* Global variables.  */
 struct emacs_globals globals;
@@ -278,14 +278,6 @@ static void sweep_strings (void);
 static void free_misc (Lisp_Object);
 extern Lisp_Object which_symbols (Lisp_Object, EMACS_INT) EXTERNALLY_VISIBLE;
 
-/* Handy constants for vectorlike objects.  */
-enum
-  {
-    header_size = offsetof (struct Lisp_Vector, contents),
-    bool_header_size = offsetof (struct Lisp_Bool_Vector, data),
-    word_size = sizeof (Lisp_Object)
-  };
-
 /* When scanning the C stack for live Lisp objects, Emacs keeps track
    of what memory allocated via lisp_malloc is intended for what
    purpose.  This enumeration specifies the type of memory.  */
@@ -2810,9 +2802,9 @@ listn (enum constype type, ptrdiff_t count, Lisp_Object arg, ...)
   Lisp_Object val, *objp;
 
   /* Change to SAFE_ALLOCA if you hit this eassert.  */
-  eassert (count <= MAX_ALLOCA / sizeof (Lisp_Object));
+  eassert (count <= MAX_ALLOCA / word_size);
 
-  objp = alloca (count * sizeof (Lisp_Object));
+  objp = alloca (count * word_size);
   objp[0] = arg;
   va_start (ap, arg);
   for (i = 1; i < count; i++)