Omit some unnecessary casts.

Many of these go back to the old pre-C89 days, when they may have
been needed, but we've been assuming C89 or later for a while now.
* alloc.c (live_string_p, live_cons_p, live_symbol_p)
(live_float_p, live_misc_p, live_vector_p):
* buffer.c (compare_overlays, cmp_for_strings, mmap_find)
(mmap_alloc, alloc_buffer_text, enlarge_buffer_text)
(defvar_per_buffer):
* callint.c (Fcall_interactively):
* doc.c (Fsubstitute_command_keys):
* filelock.c (get_boot_time):
* frame.c (xrdb_get_resource):
* gtkutil.c (hierarchy_ch_cb, qttip_cb, style_changed_cb)
(delete_cb, xg_dialog_response_cb, xg_maybe_add_timer)
(xg_get_file_name_from_selector, menuitem_destroy_callback)
(menuitem_highlight_callback, menu_destroy_callback)
(xg_update_menu_item, xg_modify_menubar_widgets, menubar_map_cb)
(xg_tool_bar_callback, xg_get_tool_bar_widgets)
(xg_tool_bar_detach_callback, xg_tool_bar_attach_callback)
(xg_tool_bar_help_callback, tb_size_cb):
* image.c (xpm_alloc_color, png_read_from_memory)
(png_read_from_file, png_load_body, our_memory_skip_input_data)
(jpeg_memory_src, jpeg_file_src, imagemagick_load_image)
(syms_of_image):
* keymap.c (describe_map):
* nsfns.m (Fns_display_monitor_attributes_list):
* nsmenu.m (process_dialog:):
* nsterm.m (hold_event):
* process.c (wait_reading_process_output):
* regex.c (REGEX_REALLOCATE, re_set_registers, re_exec, regexec):
* scroll.c (do_direct_scrolling, scrolling_1):
* termcap.c (tgetent):
* window.c (check_window_containing, add_window_to_list)
(freeze_window_starts):
* xdisp.c (compare_overlay_entries, vmessage):
* xfns.c (x_window, x_get_monitor_attributes_xinerama)
(x_get_monitor_attributes_xrandr)
(Fx_display_monitor_attributes_list, x_display_info_for_name)
(Fx_open_connection, file_dialog_cb, file_dialog_unmap_cb):
* xfont.c (xfont_match, xfont_open):
* xmenu.c (x_menu_wait_for_event, menu_highlight_callback)
(menubar_selection_callback, menu_position_func)
(popup_selection_callback, create_and_show_popup_menu)
(dialog_selection_callback, create_and_show_dialog):
* xrdb.c (x_get_string_resource):
(main) [TESTRM]:
* xsmfns.c (x_session_check_input):
* xterm.c (x_draw_glyphless_glyph_string_foreground)
(xm_scroll_callback, xg_scroll_callback, xg_end_scroll_callback)
(xaw_jump_callback, xaw_scroll_callback):
Omit unnecessary casts.

25 files changed, 177 insertions, 163 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 976d068dadc..e114db5c8d4 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,57 @@
+2013-08-11  Paul Eggert  <eggert@cs.ucla.edu>
+
+        Omit some unnecessary casts.
+        Many of these go back to the old pre-C89 days, when they may have
+        been needed, but we've been assuming C89 or later for a while now.
+        * alloc.c (live_string_p, live_cons_p, live_symbol_p)
+        (live_float_p, live_misc_p, live_vector_p):
+        * buffer.c (compare_overlays, cmp_for_strings, mmap_find)
+        (mmap_alloc, alloc_buffer_text, enlarge_buffer_text)
+        (defvar_per_buffer):
+        * callint.c (Fcall_interactively):
+        * doc.c (Fsubstitute_command_keys):
+        * filelock.c (get_boot_time):
+        * frame.c (xrdb_get_resource):
+        * gtkutil.c (hierarchy_ch_cb, qttip_cb, style_changed_cb)
+        (delete_cb, xg_dialog_response_cb, xg_maybe_add_timer)
+        (xg_get_file_name_from_selector, menuitem_destroy_callback)
+        (menuitem_highlight_callback, menu_destroy_callback)
+        (xg_update_menu_item, xg_modify_menubar_widgets, menubar_map_cb)
+        (xg_tool_bar_callback, xg_get_tool_bar_widgets)
+        (xg_tool_bar_detach_callback, xg_tool_bar_attach_callback)
+        (xg_tool_bar_help_callback, tb_size_cb):
+        * image.c (xpm_alloc_color, png_read_from_memory)
+        (png_read_from_file, png_load_body, our_memory_skip_input_data)
+        (jpeg_memory_src, jpeg_file_src, imagemagick_load_image)
+        (syms_of_image):
+        * keymap.c (describe_map):
+        * nsfns.m (Fns_display_monitor_attributes_list):
+        * nsmenu.m (process_dialog:):
+        * nsterm.m (hold_event):
+        * process.c (wait_reading_process_output):
+        * regex.c (REGEX_REALLOCATE, re_set_registers, re_exec, regexec):
+        * scroll.c (do_direct_scrolling, scrolling_1):
+        * termcap.c (tgetent):
+        * window.c (check_window_containing, add_window_to_list)
+        (freeze_window_starts):
+        * xdisp.c (compare_overlay_entries, vmessage):
+        * xfns.c (x_window, x_get_monitor_attributes_xinerama)
+        (x_get_monitor_attributes_xrandr)
+        (Fx_display_monitor_attributes_list, x_display_info_for_name)
+        (Fx_open_connection, file_dialog_cb, file_dialog_unmap_cb):
+        * xfont.c (xfont_match, xfont_open):
+        * xmenu.c (x_menu_wait_for_event, menu_highlight_callback)
+        (menubar_selection_callback, menu_position_func)
+        (popup_selection_callback, create_and_show_popup_menu)
+        (dialog_selection_callback, create_and_show_dialog):
+        * xrdb.c (x_get_string_resource):
+        (main) [TESTRM]:
+        * xsmfns.c (x_session_check_input):
+        * xterm.c (x_draw_glyphless_glyph_string_foreground)
+        (xm_scroll_callback, xg_scroll_callback, xg_end_scroll_callback)
+        (xaw_jump_callback, xaw_scroll_callback):
+        Omit unnecessary casts.
+
 2013-08-10  Paul Eggert  <eggert@cs.ucla.edu>
 
         Minor string-length refactoring.
diff --git a/src/alloc.c b/src/alloc.c
index f9bcaed0117..2c2232601cb 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -4058,7 +4058,7 @@ live_string_p (struct mem_node *m, void *p)
 {
   if (m->type == MEM_TYPE_STRING)
     {
-      struct string_block *b = (struct string_block *) m->start;
+      struct string_block *b = m->start;
       ptrdiff_t offset = (char *) p - (char *) &b->strings[0];
 
       /* P must point to the start of a Lisp_String structure, and it
@@ -4081,7 +4081,7 @@ live_cons_p (struct mem_node *m, void *p)
 {
   if (m->type == MEM_TYPE_CONS)
     {
-      struct cons_block *b = (struct cons_block *) m->start;
+      struct cons_block *b = m->start;
       ptrdiff_t offset = (char *) p - (char *) &b->conses[0];
 
       /* P must point to the start of a Lisp_Cons, not be
@@ -4107,7 +4107,7 @@ live_symbol_p (struct mem_node *m, void *p)
 {
   if (m->type == MEM_TYPE_SYMBOL)
     {
-      struct symbol_block *b = (struct symbol_block *) m->start;
+      struct symbol_block *b = m->start;
       ptrdiff_t offset = (char *) p - (char *) &b->symbols[0];
 
       /* P must point to the start of a Lisp_Symbol, not be
@@ -4133,7 +4133,7 @@ live_float_p (struct mem_node *m, void *p)
 {
   if (m->type == MEM_TYPE_FLOAT)
     {
-      struct float_block *b = (struct float_block *) m->start;
+      struct float_block *b = m->start;
       ptrdiff_t offset = (char *) p - (char *) &b->floats[0];
 
       /* P must point to the start of a Lisp_Float and not be
@@ -4157,7 +4157,7 @@ live_misc_p (struct mem_node *m, void *p)
 {
   if (m->type == MEM_TYPE_MISC)
     {
-      struct marker_block *b = (struct marker_block *) m->start;
+      struct marker_block *b = m->start;
       ptrdiff_t offset = (char *) p - (char *) &b->markers[0];
 
       /* P must point to the start of a Lisp_Misc, not be
@@ -4184,7 +4184,7 @@ live_vector_p (struct mem_node *m, void *p)
   if (m->type == MEM_TYPE_VECTOR_BLOCK)
     {
       /* This memory node corresponds to a vector block.  */
-      struct vector_block *block = (struct vector_block *) m->start;
+      struct vector_block *block = m->start;
       struct Lisp_Vector *vector = (struct Lisp_Vector *) block->data;
 
       /* P is in the block's allocation range.  Scan the block
diff --git a/src/buffer.c b/src/buffer.c
index ce4b44c87c3..5244b7043dc 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -3146,8 +3146,8 @@ struct sortvec
 static int
 compare_overlays (const void *v1, const void *v2)
 {
-  const struct sortvec *s1 = (const struct sortvec *) v1;
-  const struct sortvec *s2 = (const struct sortvec *) v2;
+  const struct sortvec *s1 = v1;
+  const struct sortvec *s2 = v2;
   if (s1->priority != s2->priority)
     return s1->priority < s2->priority ? -1 : 1;
   if (s1->beg != s2->beg)
@@ -3253,8 +3253,8 @@ static ptrdiff_t overlay_str_len;
 static int
 cmp_for_strings (const void *as1, const void *as2)
 {
-  struct sortstr *s1 = (struct sortstr *)as1;
-  struct sortstr *s2 = (struct sortstr *)as2;
+  struct sortstr const *s1 = as1;
+  struct sortstr const *s2 = as2;
   if (s1->size != s2->size)
     return s2->size < s1->size ? -1 : 1;
   if (s1->priority != s2->priority)
@@ -4752,7 +4752,7 @@ static struct mmap_region *
 mmap_find (void *start, void *end)
 {
   struct mmap_region *r;
-  char *s = (char *) start, *e = (char *) end;
+  char *s = start, *e = end;
 
   for (r = mmap_regions; r; r = r->next)
     {
@@ -4911,7 +4911,7 @@ mmap_alloc (void **var, size_t nbytes)
     }
   else
     {
-      struct mmap_region *r = (struct mmap_region *) p;
+      struct mmap_region *r = p;
 
       r->nbytes_specified = nbytes;
       r->nbytes_mapped = map;
@@ -5051,7 +5051,7 @@ alloc_buffer_text (struct buffer *b, ptrdiff_t nbytes)
       memory_full (nbytes);
     }
 
-  b->text->beg = (unsigned char *) p;
+  b->text->beg = p;
   unblock_input ();
 }
 
@@ -5079,7 +5079,7 @@ enlarge_buffer_text (struct buffer *b, ptrdiff_t delta)
       memory_full (nbytes);
     }
 
-  BUF_BEG_ADDR (b) = (unsigned char *) p;
+  BUF_BEG_ADDR (b) = p;
   unblock_input ();
 }
 
@@ -5397,11 +5397,7 @@ defvar_per_buffer (struct Lisp_Buffer_Objfwd *bo_fwd, const char *namestring,
   bo_fwd->predicate = predicate;
   sym->declared_special = 1;
   sym->redirect = SYMBOL_FORWARDED;
-  {
-    /* I tried to do the job without a cast, but it seems impossible.
-       union Lisp_Fwd *fwd; &(fwd->u_buffer_objfwd) = bo_fwd;  */
-    SET_SYMBOL_FWD (sym, (union Lisp_Fwd *)bo_fwd);
-  }
+  SET_SYMBOL_FWD (sym, (union Lisp_Fwd *) bo_fwd);
   XSETSYMBOL (PER_BUFFER_SYMBOL (offset), sym);
 
   if (PER_BUFFER_IDX (offset) == 0)
diff --git a/src/callint.c b/src/callint.c
index 38431226508..f43a5a990db 100644
--- a/src/callint.c
+++ b/src/callint.c
@@ -529,7 +529,7 @@ invoke it.  If KEYS is omitted or nil, the return value of
                               make_number (SCHARS (callint_message)),
                               Qface, Qminibuffer_prompt, callint_message);
           args[i] = Fread_char (callint_message, Qnil, Qnil);
-          message1_nolog ((char *) 0);
+          message1_nolog (0);
           /* Passing args[i] directly stimulates compiler bug.  */
           teml = args[i];
           /* See bug#8479.  */
diff --git a/src/doc.c b/src/doc.c
index 009616f4f87..d3f8fde08f6 100644
--- a/src/doc.c
+++ b/src/doc.c
@@ -905,7 +905,7 @@ Otherwise, return a new string, without any text properties.  */)
                  If this one's not active, get nil.  */
               earlier_maps = Fcdr (Fmemq (tem, Freverse (active_maps)));
               describe_map_tree (tem, 1, Fnreverse (earlier_maps),
-                                 Qnil, (char *)0, 1, 0, 0, 1);
+                                 Qnil, 0, 1, 0, 0, 1);
             }
           tem = Fbuffer_string ();
           Ferase_buffer ();
diff --git a/src/filelock.c b/src/filelock.c
index cb0bd5c7b96..df72eff5950 100644
--- a/src/filelock.c
+++ b/src/filelock.c
@@ -181,7 +181,7 @@ get_boot_time (void)
      since utmp is typically much smaller than wtmp.
      Passing a null pointer causes get_boot_time_1
      to inspect the default file, namely utmp.  */
-  get_boot_time_1 ((char *) 0, 0);
+  get_boot_time_1 (0, 0);
   if (boot_time)
     return boot_time;
 
diff --git a/src/frame.c b/src/frame.c
index 9989ef7af13..a1f151a221e 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -3544,7 +3544,7 @@ xrdb_get_resource (XrmDatabase rdb, Lisp_Object attribute, Lisp_Object class, Li
 
   value = x_get_string_resource (rdb, name_key, class_key);
 
-  if (value != (char *) 0 && *value)
+  if (value && *value)
     return build_string (value);
   else
     return Qnil;
diff --git a/src/gtkutil.c b/src/gtkutil.c
index 237d031295c..7e304d417d8 100644
--- a/src/gtkutil.c
+++ b/src/gtkutil.c
@@ -641,7 +641,7 @@ hierarchy_ch_cb (GtkWidget *widget,
                  GtkWidget *previous_toplevel,
                  gpointer   user_data)
 {
-  struct frame *f = (struct frame *) user_data;
+  struct frame *f = user_data;
   struct x_output *x = f->output_data.x;
   GtkWidget *top = gtk_widget_get_toplevel (x->ttip_lbl);
 
@@ -663,7 +663,7 @@ qttip_cb (GtkWidget  *widget,
           GtkTooltip *tooltip,
           gpointer    user_data)
 {
-  struct frame *f = (struct frame *) user_data;
+  struct frame *f = user_data;
   struct x_output *x = f->output_data.x;
   if (x->ttip_widget == NULL)
     {
@@ -1073,7 +1073,7 @@ style_changed_cb (GObject *go,
                   gpointer user_data)
 {
   struct input_event event;
-  GdkDisplay *gdpy = (GdkDisplay *) user_data;
+  GdkDisplay *gdpy = user_data;
   const char *display_name = gdk_display_get_name (gdpy);
   Display *dpy = GDK_DISPLAY_XDISPLAY (gdpy);
 
@@ -1115,7 +1115,7 @@ delete_cb (GtkWidget *widget,
 #ifdef HAVE_GTK3
   /* The event doesn't arrive in the normal event loop.  Send event
      here.  */
-  struct frame *f = (struct frame *) user_data;
+  struct frame *f = user_data;
   struct input_event ie;
 
   EVENT_INIT (ie);
@@ -1642,7 +1642,7 @@ xg_dialog_response_cb (GtkDialog *w,
                        gint response,
                        gpointer user_data)
 {
-  struct xg_dialog_data *dd = (struct xg_dialog_data *)user_data;
+  struct xg_dialog_data *dd = user_data;
   dd->response = response;
   g_main_loop_quit (dd->loop);
 }
@@ -1671,7 +1671,7 @@ pop_down_dialog (void *arg)
 static gboolean
 xg_maybe_add_timer (gpointer data)
 {
-  struct xg_dialog_data *dd = (struct xg_dialog_data *) data;
+  struct xg_dialog_data *dd = data;
   EMACS_TIME next_time = timer_check ();
 
   dd->timerid = 0;
@@ -1921,7 +1921,7 @@ static char *
 xg_get_file_name_from_selector (GtkWidget *w)
 {
   GtkFileSelection *filesel = GTK_FILE_SELECTION (w);
-  return xstrdup ((char*) gtk_file_selection_get_filename (filesel));
+  return xstrdup (gtk_file_selection_get_filename (filesel));
 }
 
 /* Create a file selection dialog.
@@ -2277,7 +2277,7 @@ menuitem_destroy_callback (GtkWidget *w, gpointer client_data)
 {
   if (client_data)
     {
-      xg_menu_item_cb_data *data = (xg_menu_item_cb_data*) client_data;
+      xg_menu_item_cb_data *data = client_data;
       xg_list_remove (&xg_menu_item_cb_list, &data->ptrs);
       xfree (data);
     }
@@ -2301,8 +2301,7 @@ menuitem_highlight_callback (GtkWidget *w,
 
   ev.crossing = *event;
   subwidget = gtk_get_event_widget (&ev);
-  data = (xg_menu_item_cb_data *) g_object_get_data (G_OBJECT (subwidget),
-                                                     XG_ITEM_DATA);
+  data = g_object_get_data (G_OBJECT (subwidget), XG_ITEM_DATA);
   if (data)
     {
       if (! NILP (data->help) && data->cl_data->highlight_cb)
@@ -2323,7 +2322,7 @@ menuitem_highlight_callback (GtkWidget *w,
 static void
 menu_destroy_callback (GtkWidget *w, gpointer client_data)
 {
-  unref_cl_data ((xg_menu_cb_data*) client_data);
+  unref_cl_data (client_data);
 }
 
 /* Make a GTK widget that contains both UTF8_LABEL and UTF8_KEY (both
@@ -3064,8 +3063,7 @@ xg_update_menu_item (widget_value *val,
   else if (val->enabled && ! gtk_widget_get_sensitive (w))
     gtk_widget_set_sensitive (w, TRUE);
 
-  cb_data = (xg_menu_item_cb_data*) g_object_get_data (G_OBJECT (w),
-                                                       XG_ITEM_DATA);
+  cb_data = g_object_get_data (G_OBJECT (w), XG_ITEM_DATA);
   if (cb_data)
     {
       cb_data->call_data = val->call_data;
@@ -3271,8 +3269,7 @@ xg_modify_menubar_widgets (GtkWidget *menubar, struct frame *f,
 
   if (! list) return;
 
-  cl_data = (xg_menu_cb_data*) g_object_get_data (G_OBJECT (menubar),
-                                                  XG_FRAME_DATA);
+  cl_data = g_object_get_data (G_OBJECT (menubar), XG_FRAME_DATA);
 
   xg_update_menubar (menubar, f, &list, list, 0, val->contents,
                      select_cb, deactivate_cb, highlight_cb, cl_data);
@@ -3336,7 +3333,7 @@ static void
 menubar_map_cb (GtkWidget *w, gpointer user_data)
 {
   GtkRequisition req;
-  struct frame *f = (struct frame *) user_data;
+  struct frame *f = user_data;
   gtk_widget_get_preferred_size (w, NULL, &req);
   if (FRAME_MENUBAR_HEIGHT (f) != req.height)
     {
@@ -3946,8 +3943,7 @@ xg_tool_bar_callback (GtkWidget *w, gpointer client_data)
   gpointer gmod = g_object_get_data (G_OBJECT (w), XG_TOOL_BAR_LAST_MODIFIER);
   intptr_t mod = (intptr_t) gmod;
 
-  struct frame *f = (struct frame *) g_object_get_data (G_OBJECT (w),
-                                                        XG_FRAME_DATA);
+  struct frame *f = g_object_get_data (G_OBJECT (w), XG_FRAME_DATA);
   Lisp_Object key, frame;
   struct input_event event;
   EVENT_INIT (event);
@@ -4020,8 +4016,8 @@ static GtkWidget *
 xg_get_tool_bar_widgets (GtkWidget *vb, GtkWidget **wimage)
 {
   GList *clist = gtk_container_get_children (GTK_CONTAINER (vb));
-  GtkWidget *c1 = (GtkWidget *) clist->data;
-  GtkWidget *c2 = clist->next ? (GtkWidget *) clist->next->data : NULL;
+  GtkWidget *c1 = clist->data;
+  GtkWidget *c2 = clist->next ? clist->next->data : NULL;
 
   *wimage = GTK_IS_IMAGE (c1) ? c1 : c2;
   g_list_free (clist);
@@ -4150,7 +4146,7 @@ xg_tool_bar_detach_callback (GtkHandleBox *wbox,
                              GtkWidget *w,
                              gpointer client_data)
 {
-  struct frame *f = (struct frame *) client_data;
+  struct frame *f = client_data;
 
   g_object_set (G_OBJECT (w), "show-arrow", !x_gtk_whole_detached_tool_bar,
                 NULL);
@@ -4187,7 +4183,7 @@ xg_tool_bar_attach_callback (GtkHandleBox *wbox,
                              GtkWidget *w,
                              gpointer client_data)
 {
-  struct frame *f = (struct frame *) client_data;
+  struct frame *f = client_data;
   g_object_set (G_OBJECT (w), "show-arrow", TRUE, NULL);
 
   if (f)
@@ -4225,8 +4221,7 @@ xg_tool_bar_help_callback (GtkWidget *w,
                            gpointer client_data)
 {
   intptr_t idx = (intptr_t) client_data;
-  struct frame *f = (struct frame *) g_object_get_data (G_OBJECT (w),
-                                                        XG_FRAME_DATA);
+  struct frame *f = g_object_get_data (G_OBJECT (w), XG_FRAME_DATA);
   Lisp_Object help, frame;
 
   if (! f || ! f->n_tool_bar_items || NILP (f->tool_bar_items))
@@ -4366,7 +4361,7 @@ tb_size_cb (GtkWidget    *widget,
   /* When tool bar is created it has one preferred size.  But when size is
      allocated between widgets, it may get another.  So we must update
      size hints if tool bar size changes.  Seen on Fedora 18 at least.  */
-  struct frame *f = (struct frame *) user_data;
+  struct frame *f = user_data;
   if (xg_update_tool_bar_sizes (f))
     x_wm_set_size_hint (f, 0, 0);
 }
diff --git a/src/image.c b/src/image.c
index 911ca8e6681..ae38b4f7648 100644
--- a/src/image.c
+++ b/src/image.c
@@ -3332,7 +3332,7 @@ static int
 xpm_alloc_color (Display *dpy, Colormap cmap, char *color_name, XColor *color,
                  void *closure)
 {
-  return xpm_lookup_color ((struct frame *) closure, color_name, color);
+  return xpm_lookup_color (closure, color_name, color);
 }
 
 
@@ -5652,8 +5652,7 @@ struct png_memory_storage
 static void
 png_read_from_memory (png_structp png_ptr, png_bytep data, png_size_t length)
 {
-  struct png_memory_storage *tbr
-    = (struct png_memory_storage *) fn_png_get_io_ptr (png_ptr);
+  struct png_memory_storage *tbr = fn_png_get_io_ptr (png_ptr);
 
   if (length > tbr->len - tbr->index)
     fn_png_error (png_ptr, "Read error");
@@ -5670,7 +5669,7 @@ png_read_from_memory (png_structp png_ptr, png_bytep data, png_size_t length)
 static void
 png_read_from_file (png_structp png_ptr, png_bytep data, png_size_t length)
 {
-  FILE *fp = (FILE *) fn_png_get_io_ptr (png_ptr);
+  FILE *fp = fn_png_get_io_ptr (png_ptr);
 
   if (fread (data, 1, length, fp) < length)
     fn_png_error (png_ptr, "Read error");
@@ -5814,9 +5813,9 @@ png_load_body (struct frame *f, struct image *img, struct png_load_context *c)
 
   /* Read image info.  */
   if (!NILP (specified_data))
-    fn_png_set_read_fn (png_ptr, (void *) &tbr, png_read_from_memory);
+    fn_png_set_read_fn (png_ptr, &tbr, png_read_from_memory);
   else
-    fn_png_set_read_fn (png_ptr, (void *) fp, png_read_from_file);
+    fn_png_set_read_fn (png_ptr, fp, png_read_from_file);
 
   fn_png_set_sig_bytes (png_ptr, sizeof sig);
   fn_png_read_info (png_ptr, info_ptr);
@@ -6306,7 +6305,7 @@ our_memory_fill_input_buffer (j_decompress_ptr cinfo)
 static void
 our_memory_skip_input_data (j_decompress_ptr cinfo, long int num_bytes)
 {
-  struct jpeg_source_mgr *src = (struct jpeg_source_mgr *) cinfo->src;
+  struct jpeg_source_mgr *src = cinfo->src;
 
   if (src)
     {
@@ -6326,19 +6325,17 @@ our_memory_skip_input_data (j_decompress_ptr cinfo, long int num_bytes)
 static void
 jpeg_memory_src (j_decompress_ptr cinfo, JOCTET *data, ptrdiff_t len)
 {
-  struct jpeg_source_mgr *src;
+  struct jpeg_source_mgr *src = cinfo->src;
 
-  if (cinfo->src == NULL)
+  if (! src)
     {
       /* First time for this JPEG object?  */
-      cinfo->src = (struct jpeg_source_mgr *)
-        (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
-                                    sizeof (struct jpeg_source_mgr));
-      src = (struct jpeg_source_mgr *) cinfo->src;
+      src = cinfo->mem->alloc_small ((j_common_ptr) cinfo,
+                                     JPOOL_PERMANENT, sizeof *src);
+      cinfo->src = src;
       src->next_input_byte = data;
     }
 
-  src = (struct jpeg_source_mgr *) cinfo->src;
   src->init_source = our_common_init_source;
   src->fill_input_buffer = our_memory_fill_input_buffer;
   src->skip_input_data = our_memory_skip_input_data;
@@ -6430,20 +6427,17 @@ our_stdio_skip_input_data (j_decompress_ptr cinfo, long int num_bytes)
 static void
 jpeg_file_src (j_decompress_ptr cinfo, FILE *fp)
 {
-  struct jpeg_stdio_mgr *src;
+  struct jpeg_stdio_mgr *src = (struct jpeg_stdio_mgr *) cinfo->src;
 
-  if (cinfo->src != NULL)
-      src = (struct jpeg_stdio_mgr *) cinfo->src;
-  else
+  if (! src)
     {
       /* First time for this JPEG object?  */
-      cinfo->src = (struct jpeg_source_mgr *)
-        (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
-                                    sizeof (struct jpeg_stdio_mgr));
-      src = (struct jpeg_stdio_mgr *) cinfo->src;
-      src->buffer = (JOCTET *)
-          (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
-                                      JPEG_STDIO_BUFFER_SIZE);
+      src = cinfo->mem->alloc_small ((j_common_ptr) cinfo,
+                                     JPOOL_PERMANENT, sizeof *src);
+      cinfo->src = (struct jpeg_source_mgr *) src;
+      src->buffer = cinfo->mem->alloc_small ((j_common_ptr) cinfo,
+                                             JPOOL_PERMANENT,
+                                             JPEG_STDIO_BUFFER_SIZE);
     }
 
   src->file = fp;
@@ -8120,7 +8114,7 @@ imagemagick_load_image (struct frame *f, struct image *img,
 
       /* Copy pixels from the imagemagick image structure to the x image map. */
       iterator = NewPixelIterator (image_wand);
-      if (iterator == (PixelIterator *) NULL)
+      if (! iterator)
         {
 #ifdef COLOR_TABLE_SUPPORT
           free_color_table ();
@@ -8135,7 +8129,7 @@ imagemagick_load_image (struct frame *f, struct image *img,
       for (y = 0; y < image_height; y++)
         {
           pixels = PixelGetNextIteratorRow (iterator, &width);
-          if (pixels == (PixelWand **) NULL)
+          if (! pixels)
             break;
           for (x = 0; x < (long) width; x++)
             {
@@ -9200,7 +9194,7 @@ A cross is always drawn on black & white displays.  */);
 
   DEFVAR_LISP ("x-bitmap-file-path", Vx_bitmap_file_path,
     doc: /* List of directories to search for window system bitmap files.  */);
-  Vx_bitmap_file_path = decode_env_path ((char *) 0, PATH_BITMAPS);
+  Vx_bitmap_file_path = decode_env_path (0, PATH_BITMAPS);
 
   DEFVAR_LISP ("image-cache-eviction-delay", Vimage_cache_eviction_delay,
     doc: /* Maximum time after which images are removed from the cache.
diff --git a/src/keymap.c b/src/keymap.c
index d13a6274347..7a18cd5d983 100644
--- a/src/keymap.c
+++ b/src/keymap.c
@@ -3249,8 +3249,7 @@ describe_map (Lisp_Object map, Lisp_Object prefix,
   for (tail = map; CONSP (tail); tail = XCDR (tail))
     length_needed++;
 
-  vect = ((struct describe_map_elt *)
-          alloca (sizeof (struct describe_map_elt) * length_needed));
+  vect = alloca (length_needed * sizeof *vect);
 
   for (tail = map; CONSP (tail); tail = XCDR (tail))
     {
diff --git a/src/nsfns.m b/src/nsfns.m
index 3f43afde787..64db1b7fd0a 100644
--- a/src/nsfns.m
+++ b/src/nsfns.m
@@ -2447,7 +2447,7 @@ Internal use only, use `display-monitor-attributes-list' instead.  */)
   if (n_monitors == 0)
     return Qnil;
 
-  monitors = (struct MonitorInfo *) xzalloc (n_monitors * sizeof (*monitors));
+  monitors = xzalloc (n_monitors * sizeof *monitors);
 
   for (i = 0; i < [screens count]; ++i)
     {
diff --git a/src/nsmenu.m b/src/nsmenu.m
index 464be89c524..5b3c21424e9 100644
--- a/src/nsmenu.m
+++ b/src/nsmenu.m
@@ -1665,7 +1665,7 @@ ns_popup_dialog (Lisp_Object position, Lisp_Object contents, Lisp_Object header)
     }
 
   if (buttons > 0)
-    button_values = (Lisp_Object *) xmalloc (buttons * sizeof (*button_values));
+    button_values = xmalloc (buttons * sizeof *button_values);
 
   for (; XTYPE (list) == Lisp_Cons; list = XCDR (list))
     {
diff --git a/src/nsterm.m b/src/nsterm.m
index 4a1c04ffb8f..d391d39fdaa 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -344,8 +344,8 @@ hold_event (struct input_event *event)
     {
       if (hold_event_q.cap == 0) hold_event_q.cap = 10;
       else hold_event_q.cap *= 2;
-      hold_event_q.q = (struct input_event *)
-        xrealloc (hold_event_q.q, hold_event_q.cap * sizeof (*hold_event_q.q));
+      hold_event_q.q =
+        xrealloc (hold_event_q.q, hold_event_q.cap * sizeof *hold_event_q.q);
     }
 
   hold_event_q.q[hold_event_q.nr++] = *event;
diff --git a/src/process.c b/src/process.c
index 85d07028c59..99c707ff97b 100644
--- a/src/process.c
+++ b/src/process.c
@@ -4526,7 +4526,7 @@ wait_reading_process_output (intmax_t time_limit, int nsecs, int read_kbd,
 #endif
             (max (max_process_desc, max_input_desc) + 1,
              &Available,
-             (check_write ? &Writeok : (SELECT_TYPE *)0),
+             (check_write ? &Writeok : 0),
              NULL, &timeout, NULL);
 
 #ifdef HAVE_GNUTLS
diff --git a/src/regex.c b/src/regex.c
index 39adb080efd..06a9db2c55c 100644
--- a/src/regex.c
+++ b/src/regex.c
@@ -468,7 +468,7 @@ init_syntax_once (void)
 
 /* Assumes a `char *destination' variable.  */
 # define REGEX_REALLOCATE(source, osize, nsize)                         \
-  (destination = (char *) alloca (nsize),                               \
+  (destination = alloca (nsize),                                        \
    memcpy (destination, source, osize))
 
 /* No need to do anything to free, after alloca.  */
@@ -4208,7 +4208,7 @@ re_set_registers (struct re_pattern_buffer *bufp, struct re_registers *regs, uns
     {
       bufp->regs_allocated = REGS_UNALLOCATED;
       regs->num_regs = 0;
-      regs->start = regs->end = (regoff_t *) 0;
+      regs->start = regs->end = 0;
     }
 }
 WEAK_ALIAS (__re_set_registers, re_set_registers)
@@ -6395,8 +6395,7 @@ weak_function
 re_exec (const char *s)
 {
   const size_t len = strlen (s);
-  return (re_search (&re_comp_buf, s, len, 0, len, (struct re_registers *) 0)
-          >= 0);
+  return re_search (&re_comp_buf, s, len, 0, len, 0) >= 0;
 }
 #endif /* _REGEX_RE_COMP */
 
@@ -6560,7 +6559,7 @@ regexec (const regex_t *_Restrict_ preg, const char *_Restrict_ string,
   /* Perform the searching operation.  */
   ret = re_search (&private_preg, string, len,
                    /* start: */ 0, /* range: */ len,
-                   want_reg_info ? &regs : (struct re_registers *) 0);
+                   want_reg_info ? &regs : 0);
 
   /* Copy the register information to the POSIX structure.  */
   if (want_reg_info)
diff --git a/src/scroll.c b/src/scroll.c
index 3e296068e8f..b9ed8c04ba8 100644
--- a/src/scroll.c
+++ b/src/scroll.c
@@ -652,8 +652,7 @@ do_direct_scrolling (struct frame *frame, struct glyph_matrix *current_matrix,
 
   /* A queue of deletions and insertions to be performed.  */
   struct alt_queue { int count, pos, window; };
-  struct alt_queue *queue_start = (struct alt_queue *)
-    alloca (window_size * sizeof *queue_start);
+  struct alt_queue *queue_start = alloca (window_size * sizeof *queue_start);
   struct alt_queue *queue = queue_start;
 
   /* True if a terminal window has been set with set_terminal_window.  */
@@ -797,9 +796,8 @@ scrolling_1 (struct frame *frame, int window_size, int unchanged_at_top,
              int unchanged_at_bottom, int *draw_cost, int *old_draw_cost,
              int *old_hash, int *new_hash, int free_at_end)
 {
-  struct matrix_elt *matrix;
-  matrix = ((struct matrix_elt *)
-            alloca ((window_size + 1) * (window_size + 1) * sizeof *matrix));
+  struct matrix_elt *matrix
+    = alloca ((window_size + 1) * (window_size + 1) * sizeof *matrix);
 
   if (FRAME_SCROLL_REGION_OK (frame))
     {
diff --git a/src/termcap.c b/src/termcap.c
index be05828eea6..aa225d9b3b1 100644
--- a/src/termcap.c
+++ b/src/termcap.c
@@ -406,7 +406,7 @@ tgetent (char *bp, const char *name)
 
   if (termcap_name && !filep && !strcmp (name, getenv ("TERM")))
     {
-      indirect = tgetst1 (find_capability (termcap_name, "tc"), (char **) 0);
+      indirect = tgetst1 (find_capability (termcap_name, "tc"), 0);
       if (!indirect)
         {
           if (!bp)
@@ -490,7 +490,7 @@ tgetent (char *bp, const char *name)
       /* Does this entry refer to another terminal type's entry?
          If something is found, copy it into heap and null-terminate it.  */
       tc_search_point = find_capability (tc_search_point, "tc");
-      term = tgetst1 (tc_search_point, (char **) 0);
+      term = tgetst1 (tc_search_point, 0);
     }
 
   emacs_close (fd);
diff --git a/src/window.c b/src/window.c
index 8a514d64954..31b5b2717a4 100644
--- a/src/window.c
+++ b/src/window.c
@@ -1364,7 +1364,7 @@ struct check_window_data
 static int
 check_window_containing (struct window *w, void *user_data)
 {
-  struct check_window_data *cw = (struct check_window_data *) user_data;
+  struct check_window_data *cw = user_data;
   enum window_part found;
   int continue_p = 1;
 
@@ -2164,7 +2164,7 @@ delete_deletable_window (Lisp_Object window)
 static int
 add_window_to_list (struct window *w, void *user_data)
 {
-  Lisp_Object *list = (Lisp_Object *) user_data;
+  Lisp_Object *list = user_data;
   Lisp_Object window;
   XSETWINDOW (window, w);
   *list = Fcons (window, *list);
@@ -6481,7 +6481,7 @@ freeze_window_start (struct window *w, void *freeze_p)
 void
 freeze_window_starts (struct frame *f, bool freeze_p)
 {
-  foreach_window (f, freeze_window_start, (void *) (freeze_p ? f : 0));
+  foreach_window (f, freeze_window_start, freeze_p ? f : 0);
 }
 
 
diff --git a/src/xdisp.c b/src/xdisp.c
index 35abf71e5bf..67f4720e170 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -5508,8 +5508,8 @@ next_overlay_string (struct it *it)
 static int
 compare_overlay_entries (const void *e1, const void *e2)
 {
-  struct overlay_entry *entry1 = (struct overlay_entry *) e1;
-  struct overlay_entry *entry2 = (struct overlay_entry *) e2;
+  struct overlay_entry const *entry1 = e1;
+  struct overlay_entry const *entry2 = e2;
   int result;
 
   if (entry1->after_string_p != entry2->after_string_p)
@@ -9908,7 +9908,7 @@ vmessage (const char *m, va_list ap)
               ptrdiff_t maxsize = FRAME_MESSAGE_BUF_SIZE (f);
               char *message_buf = alloca (maxsize + 1);
 
-              len = doprnt (message_buf, maxsize, m, (char *)0, ap);
+              len = doprnt (message_buf, maxsize, m, 0, ap);
 
               message3 (make_string (message_buf, len));
             }
diff --git a/src/xfns.c b/src/xfns.c
index 92a7964eb75..4f728ad59b0 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -2331,12 +2331,8 @@ x_window (struct frame *f, long window_prompting, int minibuffer_only)
   /* maybe_set_screen_title_format (shell_widget); */
 
   pane_widget = lw_create_widget ("main", "pane", widget_id_tick++,
-                                  (widget_value *) NULL,
-                                  shell_widget, False,
-                                  (lw_callback) NULL,
-                                  (lw_callback) NULL,
-                                  (lw_callback) NULL,
-                                  (lw_callback) NULL);
+                                  NULL, shell_widget, False,
+                                  NULL, NULL, NULL, NULL);
 
   ac = 0;
   XtSetArg (al[ac], XtNvisual, FRAME_X_VISUAL (f)); ac++;
@@ -2483,8 +2479,7 @@ x_window (struct frame *f, long window_prompting, int minibuffer_only)
      */
   XChangeProperty (XtDisplay (frame_widget), XtWindow (frame_widget),
                    FRAME_X_DISPLAY_INFO (f)->Xatom_wm_protocols,
-                   XA_ATOM, 32, PropModeAppend,
-                   (unsigned char*) NULL, 0);
+                   XA_ATOM, 32, PropModeAppend, NULL, 0);
 
   /* Make all the standard events reach the Emacs frame.  */
   attributes.event_mask = STANDARD_EVENT_SET;
@@ -4009,7 +4004,7 @@ x_get_monitor_attributes_xinerama (struct x_display_info *dpyinfo)
                         / x_display_pixel_width (dpyinfo));
   mm_height_per_pixel = ((double) HeightMMOfScreen (dpyinfo->screen)
                          / x_display_pixel_height (dpyinfo));
-  monitors = (struct MonitorInfo *) xzalloc (n_monitors * sizeof (*monitors));
+  monitors = xzalloc (n_monitors * sizeof *monitors);
   for (i = 0; i < n_monitors; ++i)
     {
       struct MonitorInfo *mi = &monitors[i];
@@ -4069,7 +4064,7 @@ x_get_monitor_attributes_xrandr (struct x_display_info *dpyinfo)
       return Qnil;
     }
   n_monitors = resources->noutput;
-  monitors = (struct MonitorInfo *) xzalloc (n_monitors * sizeof (*monitors));
+  monitors = xzalloc (n_monitors * sizeof *monitors);
 
 #ifdef HAVE_XRRGETOUTPUTPRIMARY
   pxid = XRRGetOutputPrimary (dpy, dpyinfo->root_window);
@@ -4225,7 +4220,7 @@ Internal use only, use `display-monitor-attributes-list' instead.  */)
 #endif
   n_monitors = gdk_screen_get_n_monitors (gscreen);
   monitor_frames = Fmake_vector (make_number (n_monitors), Qnil);
-  monitors = (struct MonitorInfo *) xzalloc (n_monitors * sizeof (*monitors));
+  monitors = xzalloc (n_monitors * sizeof *monitors);
 
   FOR_EACH_FRAME (rest, frame)
     {
@@ -4463,8 +4458,7 @@ x_display_info_for_name (Lisp_Object name)
 
   validate_x_resource_name ();
 
-  dpyinfo = x_term_init (name, (char *)0,
-                         SSDATA (Vx_resource_name));
+  dpyinfo = x_term_init (name, 0, SSDATA (Vx_resource_name));
 
   if (dpyinfo == 0)
     error ("Cannot connect to X server %s", SDATA (name));
@@ -4497,10 +4491,7 @@ terminate Emacs if we can't open the connection.
     error ("Not using X Windows"); /* That doesn't stop us anymore. */
 #endif
 
-  if (! NILP (xrm_string))
-    xrm_option = SSDATA (xrm_string);
-  else
-    xrm_option = (char *) 0;
+  xrm_option = NILP (xrm_string) ? 0 : SSDATA (xrm_string);
 
   validate_x_resource_name ();
 
@@ -5724,8 +5715,8 @@ DEFUN ("x-uses-old-gtk-dialog", Fx_uses_old_gtk_dialog,
 static void
 file_dialog_cb (Widget widget, XtPointer client_data, XtPointer call_data)
 {
-  int *result = (int *) client_data;
-  XmAnyCallbackStruct *cb = (XmAnyCallbackStruct *) call_data;
+  int *result = client_data;
+  XmAnyCallbackStruct *cb = call_data;
   *result = cb->reason;
 }
 
@@ -5738,7 +5729,7 @@ file_dialog_cb (Widget widget, XtPointer client_data, XtPointer call_data)
 static void
 file_dialog_unmap_cb (Widget widget, XtPointer client_data, XtPointer call_data)
 {
-  int *result = (int *) client_data;
+  int *result = client_data;
   *result = XmCR_CANCEL;
 }
 
diff --git a/src/xfont.c b/src/xfont.c
index f673adbbd5e..1aface6f972 100644
--- a/src/xfont.c
+++ b/src/xfont.c
@@ -593,9 +593,7 @@ xfont_match (struct frame *f, Lisp_Object spec)
     {
       if (XGetFontProperty (xfont, XA_FONT, &value))
         {
-          char *s;
-
-          s = (char *) XGetAtomName (display, (Atom) value);
+          char *s = XGetAtomName (display, (Atom) value);
 
           /* If DXPC (a Differential X Protocol Compressor)
              Ver.3.7 is running, XGetAtomName will return null
@@ -760,7 +758,7 @@ xfont_open (struct frame *f, Lisp_Object entity, int pixel_size)
       char *p0, *p;
       int dashes = 0;
 
-      p0 = p = (char *) XGetAtomName (FRAME_X_DISPLAY (f), (Atom) value);
+      p0 = p = XGetAtomName (FRAME_X_DISPLAY (f), (Atom) value);
       /* Count the number of dashes in the "full name".
          If it is too few, this isn't really the font's full name,
          so don't use it.
diff --git a/src/xmenu.c b/src/xmenu.c
index cad892444ff..95ae5393553 100644
--- a/src/xmenu.c
+++ b/src/xmenu.c
@@ -373,7 +373,7 @@ x_menu_wait_for_event (void *data)
 #elif defined USE_GTK
          ! gtk_events_pending ()
 #else
-         ! XPending ((Display*) data)
+         ! XPending (data)
 #endif
          )
     {
@@ -722,8 +722,7 @@ menu_highlight_callback (GtkWidget *widget, gpointer call_data)
   xg_menu_item_cb_data *cb_data;
   Lisp_Object help;
 
-  cb_data = (xg_menu_item_cb_data*) g_object_get_data (G_OBJECT (widget),
-                                                       XG_ITEM_DATA);
+  cb_data = g_object_get_data (G_OBJECT (widget), XG_ITEM_DATA);
   if (! cb_data) return;
 
   help = call_data ? cb_data->help : Qnil;
@@ -741,15 +740,11 @@ menu_highlight_callback (GtkWidget *widget, gpointer call_data)
 static void
 menu_highlight_callback (Widget widget, LWLIB_ID id, void *call_data)
 {
-  struct frame *f;
-  Lisp_Object help;
-
-  widget_value *wv = (widget_value *) call_data;
-
-  help = wv ? wv->help : Qnil;
+  widget_value *wv = call_data;
+  Lisp_Object help = wv ? wv->help : Qnil;
 
   /* Determine the frame for the help event.  */
-  f = menubar_id_to_frame (id);
+  struct frame *f = menubar_id_to_frame (id);
 
   show_help_event (f, widget, help);
 }
@@ -769,7 +764,7 @@ static int xg_crazy_callback_abort;
 static void
 menubar_selection_callback (GtkWidget *widget, gpointer client_data)
 {
-  xg_menu_item_cb_data *cb_data = (xg_menu_item_cb_data*) client_data;
+  xg_menu_item_cb_data *cb_data = client_data;
 
   if (xg_crazy_callback_abort)
     return;
@@ -1370,7 +1365,7 @@ struct next_popup_x_y
 static void
 menu_position_func (GtkMenu *menu, gint *x, gint *y, gboolean *push_in, gpointer user_data)
 {
-  struct next_popup_x_y* data = (struct next_popup_x_y*)user_data;
+  struct next_popup_x_y *data = user_data;
   GtkRequisition req;
   struct x_display_info *dpyinfo = FRAME_X_DISPLAY_INFO (data->f);
   int disp_width = x_display_pixel_width (dpyinfo);
@@ -1391,10 +1386,10 @@ menu_position_func (GtkMenu *menu, gint *x, gint *y, gboolean *push_in, gpointer
 static void
 popup_selection_callback (GtkWidget *widget, gpointer client_data)
 {
-  xg_menu_item_cb_data *cb_data = (xg_menu_item_cb_data*) client_data;
+  xg_menu_item_cb_data *cb_data = client_data;
 
   if (xg_crazy_callback_abort) return;
-  if (cb_data) menu_item_selection = (Lisp_Object *) cb_data->call_data;
+  if (cb_data) menu_item_selection = cb_data->call_data;
 }
 
 static void
@@ -1497,7 +1492,7 @@ LWLIB_ID widget_id_tick;
 static void
 popup_selection_callback (Widget widget, LWLIB_ID id, XtPointer client_data)
 {
-  menu_item_selection = (Lisp_Object *) client_data;
+  menu_item_selection = client_data;
 }
 
 /* ARG is the LWLIB ID of the dialog box, represented
@@ -1583,7 +1578,7 @@ create_and_show_popup_menu (struct frame *f, widget_value *first_wv,
                                   make_number (menu_id & ~(-1 << (fact)))));
 
     /* Process events that apply to the menu.  */
-    popup_get_selection ((XEvent *) 0, FRAME_X_DISPLAY_INFO (f), menu_id, 1);
+    popup_get_selection (0, FRAME_X_DISPLAY_INFO (f), menu_id, 1);
 
     unbind_to (specpdl_count, Qnil);
   }
@@ -1882,7 +1877,7 @@ dialog_selection_callback (GtkWidget *widget, gpointer client_data)
   /* Treat the pointer as an integer.  There's no problem
      as long as pointers have enough bits to hold small integers.  */
   if ((intptr_t) client_data != -1)
-    menu_item_selection = (Lisp_Object *) client_data;
+    menu_item_selection = client_data;
 
   popup_activated_flag = 0;
 }
@@ -1924,7 +1919,7 @@ dialog_selection_callback (Widget widget, LWLIB_ID id, XtPointer client_data)
   /* Treat the pointer as an integer.  There's no problem
      as long as pointers have enough bits to hold small integers.  */
   if ((intptr_t) client_data != -1)
-    menu_item_selection = (Lisp_Object *) client_data;
+    menu_item_selection = client_data;
 
   block_input ();
   lw_destroy_all_widgets (id);
@@ -1967,8 +1962,7 @@ create_and_show_dialog (struct frame *f, widget_value *first_wv)
                            Fcons (make_number (dialog_id >> (fact)),
                                   make_number (dialog_id & ~(-1 << (fact)))));
 
-    popup_get_selection ((XEvent *) 0, FRAME_X_DISPLAY_INFO (f),
-                         dialog_id, 1);
+    popup_get_selection (0, FRAME_X_DISPLAY_INFO (f), dialog_id, 1);
 
     unbind_to (count, Qnil);
   }
diff --git a/src/xrdb.c b/src/xrdb.c
index 6ef5c3bcb41..60dcdae080d 100644
--- a/src/xrdb.c
+++ b/src/xrdb.c
@@ -596,7 +596,7 @@ x_get_string_resource (XrmDatabase rdb, const char *name, const char *class)
   if (x_get_resource (rdb, name, class, x_rm_string, &value))
     return (char *) value.addr;
 
-  return (char *) 0;
+  return 0;
 }
 
 /* Stand-alone test facilities.  */
@@ -646,10 +646,7 @@ main (int argc, char **argv)
     displayname = "localhost:0.0";
 
   lp = member ("-xrm", arg_list);
-  if (! NIL (lp))
-    resource_string = car (cdr (lp));
-  else
-    resource_string = (char *) 0;
+  resource_string = NIL (lp) ? 0 : car (cdr (lp));
 
   lp = member ("-c", arg_list);
   if (! NIL (lp))
diff --git a/src/xsmfns.c b/src/xsmfns.c
index cb7122202df..526d4c3610b 100644
--- a/src/xsmfns.c
+++ b/src/xsmfns.c
@@ -107,8 +107,7 @@ x_session_check_input (int fd, void *data)
      will be called.  */
   emacs_event.kind = NO_EVENT;
 
-  ret = IceProcessMessages (SmcGetIceConnection (smc_conn),
-                            (IceReplyWaitInfo *)0, (Bool *)0);
+  ret = IceProcessMessages (SmcGetIceConnection (smc_conn), 0, 0);
   if (ret != IceProcessMessagesSuccess)
     {
       /* Either IO error or Connection closed.  */
diff --git a/src/xterm.c b/src/xterm.c
index 55347a3310e..6f57836c9aa 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -1366,7 +1366,7 @@ x_draw_glyphless_glyph_string_foreground (struct glyph_string *s)
         }
       else if (glyph->u.glyphless.method == GLYPHLESS_DISPLAY_HEX_CODE)
         {
-          sprintf ((char *) buf, "%0*X",
+          sprintf (buf, "%0*X",
                    glyph->u.glyphless.ch < 0x10000 ? 4 : 6,
                    glyph->u.glyphless.ch);
           str = buf;
@@ -4328,8 +4328,8 @@ x_scroll_bar_to_input_event (XEvent *event, struct input_event *ievent)
 static void
 xm_scroll_callback (Widget widget, XtPointer client_data, XtPointer call_data)
 {
-  struct scroll_bar *bar = (struct scroll_bar *) client_data;
-  XmScrollBarCallbackStruct *cs = (XmScrollBarCallbackStruct *) call_data;
+  struct scroll_bar *bar = client_data;
+  XmScrollBarCallbackStruct *cs = call_data;
   int part = -1, whole = 0, portion = 0;
 
   switch (cs->reason)
@@ -4403,12 +4403,11 @@ xg_scroll_callback (GtkRange     *range,
                     gdouble       value,
                     gpointer      user_data)
 {
-  struct scroll_bar *bar = (struct scroll_bar *) user_data;
+  struct scroll_bar *bar = user_data;
   gdouble position;
   int part = -1, whole = 0, portion = 0;
   GtkAdjustment *adj = GTK_ADJUSTMENT (gtk_range_get_adjustment (range));
-  struct frame *f = (struct frame *) g_object_get_data (G_OBJECT (range),
-                                                        XG_FRAME_DATA);
+  struct frame *f = g_object_get_data (G_OBJECT (range), XG_FRAME_DATA);
 
   if (xg_ignore_gtk_scrollbar) return FALSE;
   position = gtk_adjustment_get_value (adj);
@@ -4463,7 +4462,7 @@ xg_end_scroll_callback (GtkWidget *widget,
                         GdkEventButton *event,
                         gpointer user_data)
 {
-  struct scroll_bar *bar = (struct scroll_bar *) user_data;
+  struct scroll_bar *bar = user_data;
   bar->dragging = Qnil;
   if (WINDOWP (window_being_scrolled))
     {
@@ -4486,8 +4485,9 @@ xg_end_scroll_callback (GtkWidget *widget,
 static void
 xaw_jump_callback (Widget widget, XtPointer client_data, XtPointer call_data)
 {
-  struct scroll_bar *bar = (struct scroll_bar *) client_data;
-  float top = *(float *) call_data;
+  struct scroll_bar *bar = client_data;
+  float *top_addr = call_data;
+  float top = *top_addr;
   float shown;
   int whole, portion, height;
   int part;
@@ -4528,9 +4528,9 @@ xaw_jump_callback (Widget widget, XtPointer client_data, XtPointer call_data)
 static void
 xaw_scroll_callback (Widget widget, XtPointer client_data, XtPointer call_data)
 {
-  struct scroll_bar *bar = (struct scroll_bar *) client_data;
+  struct scroll_bar *bar = client_data;
   /* The position really is stored cast to a pointer.  */
-  int position = (long) call_data;
+  int position = (intptr_t) call_data;
   Dimension height;
   int part;