* xfns.c (Fx_create_frame, Fx_display_list):

* window.c (window_fixed_size_p, enlarge_window, shrink_window_lowest_first):
* macterm.c (init_font_name_table):
* macfns.c (Fx_create_frame, Fx_display_list):
* lread.c (close_load_descs):
* keyboard.c (read_char_x_menu_prompt):
* fns.c (Fmember, Fmemql, Fdelete, Fset_char_table_parent):
* coding.c (code_convert_region_unwind): Test the type of an object
rather than just !NILP before extracting data from it.

9 files changed, 32 insertions, 20 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 6f96f7da7ac..cd6dd995bcf 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,16 @@
 2007-10-16  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+        * xfns.c (Fx_create_frame, Fx_display_list):
+        * window.c (window_fixed_size_p, enlarge_window)
+        (shrink_window_lowest_first):
+        * macterm.c (init_font_name_table):
+        * macfns.c (Fx_create_frame, Fx_display_list):
+        * lread.c (close_load_descs):
+        * keyboard.c (read_char_x_menu_prompt):
+        * fns.c (Fmember, Fmemql, Fdelete, Fset_char_table_parent):
+        * coding.c (code_convert_region_unwind): Test the type of an object
+        rather than just !NILP before extracting data from it.
+
         * alloc.c (Fpurecopy): Set the pvec tag on pseudo vectors.
 
         * lisp.h (enum Lisp_Misc_Type): Del Lisp_Misc_Some_Buffer_Local_Value.
diff --git a/src/coding.c b/src/coding.c
index b6299097d55..b0721cc22be 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -5371,7 +5371,7 @@ code_convert_region_unwind (arg)
 
   inhibit_pre_post_conversion = 0;
   Vlast_coding_system_used = XCAR (arg);
-  for (arg = XCDR (arg); ! NILP (arg); arg = XCDR (arg))
+  for (arg = XCDR (arg); CONSP (arg); arg = XCDR (arg))
     Fkill_buffer (XCAR (arg));
 
   UNGCPRO;
diff --git a/src/fns.c b/src/fns.c
index f881ed53f88..7ec0056332a 100644
--- a/src/fns.c
+++ b/src/fns.c
@@ -1451,7 +1451,7 @@ The value is actually the tail of LIST whose car is ELT.  */)
      Lisp_Object list;
 {
   register Lisp_Object tail;
-  for (tail = list; !NILP (tail); tail = XCDR (tail))
+  for (tail = list; CONSP (tail); tail = XCDR (tail))
     {
       register Lisp_Object tem;
       CHECK_LIST_CONS (tail, list);
@@ -1502,7 +1502,7 @@ The value is actually the tail of LIST whose car is ELT.  */)
   if (!FLOATP (elt))
     return Fmemq (elt, list);
 
-  for (tail = list; !NILP (tail); tail = XCDR (tail))
+  for (tail = list; CONSP (tail); tail = XCDR (tail))
     {
       register Lisp_Object tem;
       CHECK_LIST_CONS (tail, list);
@@ -1806,7 +1806,7 @@ to be sure of changing the value of `foo'.  */)
     {
       Lisp_Object tail, prev;
 
-      for (tail = seq, prev = Qnil; !NILP (tail); tail = XCDR (tail))
+      for (tail = seq, prev = Qnil; CONSP (tail); tail = XCDR (tail))
         {
           CHECK_LIST_CONS (tail, seq);
 
@@ -2440,7 +2440,8 @@ Return PARENT.  PARENT must be either nil or another char-table.  */)
     {
       CHECK_CHAR_TABLE (parent);
 
-      for (temp = parent; !NILP (temp); temp = XCHAR_TABLE (temp)->parent)
+      for (temp = parent; CHAR_TABLE_P (temp);
+           temp = XCHAR_TABLE (temp)->parent)
         if (EQ (temp, char_table))
           error ("Attempt to make a chartable be its own parent");
     }
diff --git a/src/keyboard.c b/src/keyboard.c
index bd8263f9b04..fccf5c88eaa 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -8538,7 +8538,7 @@ read_char_x_menu_prompt (nmaps, maps, prev_event, used_mouse_menu)
              to indicate that they came from a mouse menu,
              so that when present in last_nonmenu_event
              they won't confuse things.  */
-          for (tem = XCDR (value); !NILP (tem); tem = XCDR (tem))
+          for (tem = XCDR (value); CONSP (tem); tem = XCDR (tem))
             {
               record_menu_key (XCAR (tem));
               if (SYMBOLP (XCAR (tem))
diff --git a/src/lread.c b/src/lread.c
index 5418d82a968..77eb800b41a 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -1100,7 +1100,7 @@ close_load_descs ()
 {
 #ifndef WINDOWSNT
   Lisp_Object tail;
-  for (tail = load_descriptor_list; !NILP (tail); tail = XCDR (tail))
+  for (tail = load_descriptor_list; CONSP (tail); tail = XCDR (tail))
     emacs_close (XFASTINT (XCAR (tail)));
 #endif
 }
diff --git a/src/macfns.c b/src/macfns.c
index 6a12c071cee..d0b859054a6 100644
--- a/src/macfns.c
+++ b/src/macfns.c
@@ -2826,7 +2826,7 @@ This function is an internal primitive--use `make-frame' instead.  */)
 
   /* All remaining specified parameters, which have not been "used"
      by x_get_arg and friends, now go in the misc. alist of the frame.  */
-  for (tem = parameters; !NILP (tem); tem = XCDR (tem))
+  for (tem = parameters; CONSP (tem); tem = XCDR (tem))
     if (CONSP (XCAR (tem)) && !NILP (XCAR (XCAR (tem))))
       f->param_alist = Fcons (XCAR (tem), f->param_alist);
 
@@ -3402,7 +3402,7 @@ DEFUN ("x-display-list", Fx_display_list, Sx_display_list, 0, 0, 0,
   Lisp_Object tail, result;
 
   result = Qnil;
-  for (tail = x_display_name_list; ! NILP (tail); tail = XCDR (tail))
+  for (tail = x_display_name_list; CONSP (tail); tail = XCDR (tail))
     result = Fcons (XCAR (XCAR (tail)), result);
 
   return result;
diff --git a/src/macterm.c b/src/macterm.c
index e4b9cca819c..ef1fa7c7453 100644
--- a/src/macterm.c
+++ b/src/macterm.c
@@ -8281,7 +8281,7 @@ init_font_name_table ()
           Lisp_Object rest = XCDR (XCDR (text_encoding_info));
 
           if (size > 0 || style == normal)
-            for (; !NILP (rest); rest = XCDR (rest))
+            for (; CONSP (rest); rest = XCDR (rest))
               add_mac_font_name (name, size, style, SDATA (XCAR (rest)));
         }
     }
@@ -8356,7 +8356,7 @@ init_font_name_table ()
                 {
                   Lisp_Object rest = XCDR (XCDR (text_encoding_info));
 
-                  for (; !NILP (rest); rest = XCDR (rest))
+                  for (; CONSP (rest); rest = XCDR (rest))
                     add_mac_font_name (name, assc_entry->fontSize,
                                        assc_entry->fontStyle,
                                        SDATA (XCAR (rest)));
diff --git a/src/window.c b/src/window.c
index efdf309121b..1819b2dc024 100644
--- a/src/window.c
+++ b/src/window.c
@@ -2670,12 +2670,12 @@ window_fixed_size_p (w, width_p, check_siblings_p)
         {
           Lisp_Object child;
 
-          for (child = w->prev; !NILP (child); child = XWINDOW (child)->prev)
+          for (child = w->prev; WINDOWP (child); child = XWINDOW (child)->prev)
             if (!window_fixed_size_p (XWINDOW (child), width_p, 0))
               break;
 
           if (NILP (child))
-            for (child = w->next; !NILP (child); child = XWINDOW (child)->next)
+            for (child = w->next; WINDOWP (child); child = XWINDOW (child)->next)
               if (!window_fixed_size_p (XWINDOW (child), width_p, 0))
                 break;
 
@@ -4291,10 +4291,10 @@ enlarge_window (window, delta, horiz_flag)
 
   /* Find the total we can get from other siblings without deleting them.  */
   maximum = 0;
-  for (next = p->next; ! NILP (next); next = XWINDOW (next)->next)
+  for (next = p->next; WINDOWP (next); next = XWINDOW (next)->next)
     maximum += (*sizefun) (next) - window_min_size (XWINDOW (next),
                                                     horiz_flag, 0, 0);
-  for (prev = p->prev; ! NILP (prev); prev = XWINDOW (prev)->prev)
+  for (prev = p->prev; WINDOWP (prev); prev = XWINDOW (prev)->prev)
     maximum += (*sizefun) (prev) - window_min_size (XWINDOW (prev),
                                                     horiz_flag, 0, 0);
 
@@ -4442,10 +4442,10 @@ enlarge_window (window, delta, horiz_flag)
           Lisp_Object s;
           int n = 1;
 
-          for (s = w->next; !NILP (s); s = XWINDOW (s)->next)
+          for (s = w->next; WINDOWP (s); s = XWINDOW (s)->next)
             if (!window_fixed_size_p (XWINDOW (s), horiz_flag, 0))
               ++n;
-          for (s = w->prev; !NILP (s); s = XWINDOW (s)->prev)
+          for (s = w->prev; WINDOWP (s); s = XWINDOW (s)->prev)
             if (!window_fixed_size_p (XWINDOW (s), horiz_flag, 0))
               ++n;
 
@@ -4701,7 +4701,7 @@ shrink_window_lowest_first (w, height)
       /* Find the last child.  We are taking space from lowest windows
          first, so we iterate over children from the last child
          backwards.  */
-      for (child = w->vchild; !NILP (child); child = XWINDOW (child)->next)
+      for (child = w->vchild; WINDOWP (child); child = XWINDOW (child)->next)
         last_child = child;
 
       /* Assign new heights.  We leave only MIN_SAFE_WINDOW_HEIGHT.  */
diff --git a/src/xfns.c b/src/xfns.c
index fe4d1c8335f..43ed2f75514 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -3468,7 +3468,7 @@ This function is an internal primitive--use `make-frame' instead.  */)
 
   /* All remaining specified parameters, which have not been "used"
      by x_get_arg and friends, now go in the misc. alist of the frame.  */
-  for (tem = parms; !NILP (tem); tem = XCDR (tem))
+  for (tem = parms; CONSP (tem); tem = XCDR (tem))
     if (CONSP (XCAR (tem)) && !NILP (XCAR (XCAR (tem))))
       f->param_alist = Fcons (XCAR (tem), f->param_alist);
 
@@ -4156,7 +4156,7 @@ DEFUN ("x-display-list", Fx_display_list, Sx_display_list, 0, 0, 0,
   Lisp_Object tail, result;
 
   result = Qnil;
-  for (tail = x_display_name_list; ! NILP (tail); tail = XCDR (tail))
+  for (tail = x_display_name_list; CONSP (tail); tail = XCDR (tail))
     result = Fcons (XCAR (XCAR (tail)), result);
 
   return result;