16 files changed, 373 insertions, 369 deletions

diff --git a/src/auto/configure b/src/auto/configure
index ca8f09659d..596e0349d5 100755
--- a/src/auto/configure
+++ b/src/auto/configure
@@ -7977,6 +7977,82 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
 
     LDFLAGS="$ac_save_LDFLAGS"
 
+    { $as_echo "$as_me:$LINENO: checking size of wchar_t is 2 bytes" >&5
+$as_echo_n "checking size of wchar_t is 2 bytes... " >&6; }
+    if test "${ac_cv_small_wchar_t+set}" = set; then
+  $as_echo_n "(cached) " >&6
+else
+  if test "$cross_compiling" = yes; then
+  { { $as_echo "$as_me:$LINENO: error: failed to compile test program" >&5
+$as_echo "$as_me: error: failed to compile test program" >&2;}
+   { (exit 1); exit 1; }; }
+else
+  cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+#include <X11/Xlib.h>
+#if STDC_HEADERS
+# include <stdlib.h>
+# include <stddef.h>
+#endif
+		main()
+		{
+		  if (sizeof(wchar_t) <= 2)
+		    exit(1);
+		  exit(0);
+		}
+_ACEOF
+rm -f conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
+$as_echo "$ac_try_echo") >&5
+  (eval "$ac_link") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } && { ac_try='./conftest$ac_exeext'
+  { (case "(($ac_try" in
+  *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+  *) ac_try_echo=$ac_try;;
+esac
+eval ac_try_echo="\"\$as_me:$LINENO: $ac_try_echo\""
+$as_echo "$ac_try_echo") >&5
+  (eval "$ac_try") 2>&5
+  ac_status=$?
+  $as_echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+  ac_cv_small_wchar_t="no"
+else
+  $as_echo "$as_me: program exited with status $ac_status" >&5
+$as_echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+( exit $ac_status )
+ac_cv_small_wchar_t="yes"
+fi
+rm -rf conftest.dSYM
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext conftest.$ac_objext conftest.$ac_ext
+fi
+
+
+fi
+
+    { $as_echo "$as_me:$LINENO: result: $ac_cv_small_wchar_t" >&5
+$as_echo "$ac_cv_small_wchar_t" >&6; }
+    if test "x$ac_cv_small_wchar_t" = "xyes" ; then
+      cat >>confdefs.h <<\_ACEOF
+#define SMALL_WCHAR_T 1
+_ACEOF
+
+    fi
+
   fi
 fi
 
@@ -15417,7 +15493,6 @@ _ACEOF
 
 
 
-
 bcopy_test_prog='
 #include "confdefs.h"
 #ifdef HAVE_STRING_H
diff --git a/src/config.h.in b/src/config.h.in
index 66baee65a5..b603c23c72 100644
--- a/src/config.h.in
+++ b/src/config.h.in
@@ -39,6 +39,9 @@
 /* Defined to the size of an int */
 #undef SIZEOF_INT
 
+/* Define when wchar_t is only 2 bytes. */
+#undef SMALL_WCHAR_T
+
 /*
  * If we cannot trust one of the following from the libraries, we use our
  * own safe but probably slower vim_memmove().
diff --git a/src/configure.in b/src/configure.in
index b17353e2f1..a644d941fc 100644
--- a/src/configure.in
+++ b/src/configure.in
@@ -1193,6 +1193,28 @@ else
 
     LDFLAGS="$ac_save_LDFLAGS"
 
+    AC_MSG_CHECKING(size of wchar_t is 2 bytes)
+    AC_CACHE_VAL(ac_cv_small_wchar_t,
+	[AC_TRY_RUN([
+#include <X11/Xlib.h>
+#if STDC_HEADERS
+# include <stdlib.h>
+# include <stddef.h>
+#endif
+		main()
+		{
+		  if (sizeof(wchar_t) <= 2)
+		    exit(1);
+		  exit(0);
+		}],
+		ac_cv_small_wchar_t="no",
+		ac_cv_small_wchar_t="yes",
+		AC_MSG_ERROR(failed to compile test program))])
+    AC_MSG_RESULT($ac_cv_small_wchar_t)
+    if test "x$ac_cv_small_wchar_t" = "xyes" ; then
+      AC_DEFINE(SMALL_WCHAR_T)
+    fi
+
   fi
 fi
 
@@ -2881,7 +2903,6 @@ main()
 AC_MSG_RESULT($ac_cv_sizeof_int)
 AC_DEFINE_UNQUOTED(SIZEOF_INT, $ac_cv_sizeof_int)
 
-
 dnl Check for memmove() before bcopy(), makes memmove() be used when both are
 dnl present, fixes problem with incompatibility between Solaris 2.4 and 2.5.
 
diff --git a/src/gui.c b/src/gui.c
index a80c9aa7a6..9c6e29c14b 100644
--- a/src/gui.c
+++ b/src/gui.c
@@ -3119,7 +3119,7 @@ static int	prev_which_scrollbars[3];
  */
     void
 gui_init_which_components(oldval)
-    char_u	*oldval;
+    char_u	*oldval UNUSED;
 {
 #ifdef FEAT_MENU
     static int	prev_menu_is_active = -1;
@@ -4668,8 +4668,8 @@ gui_mouse_correct()
  */
     static win_T *
 xy2win(x, y)
-    int		x;
-    int		y;
+    int		x UNUSED;
+    int		y UNUSED;
 {
 #ifdef FEAT_WINDOWS
     int		row;
@@ -5121,8 +5121,8 @@ gui_wingoto_xy(x, y)
  */
     void
 gui_handle_drop(x, y, modifiers, fnames, count)
-    int		x;
-    int		y;
+    int		x UNUSED;
+    int		y UNUSED;
     int_u	modifiers;
     char_u	**fnames;
     int		count;
diff --git a/src/gui_at_fs.c b/src/gui_at_fs.c
index ae68575266..0206284b2a 100644
--- a/src/gui_at_fs.c
+++ b/src/gui_at_fs.c
@@ -829,7 +829,7 @@ SFsetText(path)
     text.format = FMT8BIT;
 
 #ifdef XtNinternational
-    if (_XawTextFormat((TextWidget)selFileField) == XawFmtWide)
+    if ((unsigned long)_XawTextFormat((TextWidget)selFileField) == XawFmtWide)
     {
 	XawTextReplace(selFileField, (XawTextPosition)0,
 				    (XawTextPosition)WcsLen((wchar_t *)&SFtextBuffer[0]), &text);
@@ -851,17 +851,15 @@ SFsetText(path)
 #endif
 }
 
-/* ARGSUSED */
     static void
 SFbuttonPressList(w, n, event)
-    Widget		w;
-    int			n;
-    XButtonPressedEvent	*event;
+    Widget		w UNUSED;
+    int			n UNUSED;
+    XButtonPressedEvent	*event UNUSED;
 {
     SFbuttonPressed = 1;
 }
 
-/* ARGSUSED */
     static void
 SFbuttonReleaseList(w, n, event)
     Widget		 w;
@@ -989,11 +987,10 @@ SFcheckFiles(dir)
     return result;
 }
 
-/* ARGSUSED */
     static void
 SFdirModTimer(cl, id)
-    XtPointer		cl;
-    XtIntervalId	*id;
+    XtPointer		cl UNUSED;
+    XtIntervalId	*id UNUSED;
 {
     static int		n = -1;
     static int		f = 0;
@@ -1596,11 +1593,10 @@ SFscrollTimerInterval()
 
 static void SFscrollTimer __ARGS((XtPointer p, XtIntervalId *id));
 
-/* ARGSUSED */
     static void
 SFscrollTimer(p, id)
     XtPointer		p;
-    XtIntervalId	*id;
+    XtIntervalId	*id UNUSED;
 {
     SFDir	*dir;
     int		save;
@@ -1695,10 +1691,9 @@ SFnewInvertEntry(n, event)
     }
 }
 
-/* ARGSUSED */
     static void
 SFenterList(w, n, event)
-    Widget		w;
+    Widget		w UNUSED;
     int			n;
     XEnterWindowEvent	*event;
 {
@@ -1719,12 +1714,11 @@ SFenterList(w, n, event)
     }
 }
 
-/* ARGSUSED */
     static void
 SFleaveList(w, n, event)
-    Widget	w;
+    Widget	w UNUSED;
     int		n;
-    XEvent	*event;
+    XEvent	*event UNUSED;
 {
     if (SFcurrentInvert[n] != -1)
     {
@@ -1733,10 +1727,9 @@ SFleaveList(w, n, event)
     }
 }
 
-/* ARGSUSED */
     static void
 SFmotionList(w, n, event)
-    Widget		w;
+    Widget		w UNUSED;
     int			n;
     XMotionEvent	*event;
 {
@@ -1754,7 +1747,6 @@ SFmotionList(w, n, event)
     }
 }
 
-/* ARGSUSED */
     static void
 SFvFloatSliderMovedCallback(w, n, fnew)
     Widget	w;
@@ -1767,10 +1759,9 @@ SFvFloatSliderMovedCallback(w, n, fnew)
     SFvSliderMovedCallback(w, (int)(long)n, nw);
 }
 
-/* ARGSUSED */
     static void
 SFvSliderMovedCallback(w, n, nw)
-    Widget	w;
+    Widget	w UNUSED;
     int		n;
     int		nw;
 {
@@ -1853,10 +1844,9 @@ SFvSliderMovedCallback(w, n, nw)
     }
 }
 
-/* ARGSUSED */
     static void
 SFvAreaSelectedCallback(w, n, pnew)
-    Widget		w;
+    Widget	w;
     XtPointer	n;
     XtPointer	pnew;
 {
@@ -1914,10 +1904,9 @@ SFvAreaSelectedCallback(w, n, pnew)
     SFvSliderMovedCallback(w, (int)(long)n, nw);
 }
 
-/* ARGSUSED */
     static void
 SFhSliderMovedCallback(w, n, nw)
-    Widget	w;
+    Widget	w UNUSED;
     XtPointer	n;
     XtPointer	nw;
 {
@@ -1933,10 +1922,9 @@ SFhSliderMovedCallback(w, n, nw)
     SFdrawList((int)(long)n, SF_DO_NOT_SCROLL);
 }
 
-/* ARGSUSED */
     static void
 SFhAreaSelectedCallback(w, n, pnew)
-    Widget		w;
+    Widget	w;
     XtPointer	n;
     XtPointer	pnew;
 {
@@ -1994,11 +1982,10 @@ SFhAreaSelectedCallback(w, n, pnew)
     }
 }
 
-/* ARGSUSED */
     static void
 SFpathSliderMovedCallback(w, client_data, nw)
-    Widget		w;
-    XtPointer	client_data;
+    Widget	w UNUSED;
+    XtPointer	client_data UNUSED;
     XtPointer	nw;
 {
     SFDir		*dir;
@@ -2031,11 +2018,10 @@ SFpathSliderMovedCallback(w, client_data, nw)
     XawTextSetInsertionPoint(selFileField, pos);
 }
 
-/* ARGSUSED */
     static void
 SFpathAreaSelectedCallback(w, client_data, pnew)
     Widget	w;
-    XtPointer	client_data;
+    XtPointer	client_data UNUSED;
     XtPointer	pnew;
 {
     int		nw = (int)(long)pnew;
@@ -2206,13 +2192,12 @@ static char *oneLineTextEditTranslations = "\
 
 static void SFexposeList __ARGS((Widget w, XtPointer n, XEvent *event, Boolean *cont));
 
-/* ARGSUSED */
     static void
 SFexposeList(w, n, event, cont)
-    Widget	w;
+    Widget	w UNUSED;
     XtPointer	n;
     XEvent	*event;
-    Boolean	*cont;
+    Boolean	*cont UNUSED;
 {
     if ((event->type == NoExpose) || event->xexpose.count)
 	return;
@@ -2222,13 +2207,12 @@ SFexposeList(w, n, event, cont)
 
 static void SFmodVerifyCallback __ARGS((Widget w, XtPointer client_data, XEvent *event, Boolean *cont));
 
-/* ARGSUSED */
     static void
 SFmodVerifyCallback(w, client_data, event, cont)
-    Widget		w;
-    XtPointer		client_data;
+    Widget		w UNUSED;
+    XtPointer		client_data UNUSED;
     XEvent		*event;
-    Boolean		*cont;
+    Boolean		*cont UNUSED;
 {
     char	buf[2];
 
@@ -2241,11 +2225,11 @@ SFmodVerifyCallback(w, client_data, event, cont)
 
 static void SFokCallback __ARGS((Widget w, XtPointer cl, XtPointer cd));
 
-/* ARGSUSED */
     static void
 SFokCallback(w, cl, cd)
-    Widget	w;
-    XtPointer	cl, cd;
+    Widget	w UNUSED;
+    XtPointer	cl UNUSED;
+    XtPointer	cd UNUSED;
 {
     SFstatus = SEL_FILE_OK;
 }
@@ -2258,11 +2242,11 @@ static XtCallbackRec SFokSelect[] =
 
 static void SFcancelCallback __ARGS((Widget w, XtPointer cl, XtPointer cd));
 
-/* ARGSUSED */
     static void
 SFcancelCallback(w, cl, cd)
-    Widget	w;
-    XtPointer	cl, cd;
+    Widget	w UNUSED;
+    XtPointer	cl UNUSED;
+    XtPointer	cd UNUSED;
 {
     SFstatus = SEL_FILE_CANCEL;
 }
@@ -2275,16 +2259,15 @@ static XtCallbackRec SFcancelSelect[] =
 
 static void SFdismissAction __ARGS((Widget w, XEvent *event, String *params, Cardinal *num_params));
 
-/* ARGSUSED */
     static void
 SFdismissAction(w, event, params, num_params)
-    Widget	w;
-    XEvent *event;
-    String *params;
-    Cardinal *num_params;
+    Widget	w UNUSED;
+    XEvent	*event;
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
-    if (event->type == ClientMessage &&
-	    event->xclient.data.l[0] != SFwmDeleteWindow)
+    if (event->type == ClientMessage
+	    && (Atom)event->xclient.data.l[0] != SFwmDeleteWindow)
 	return;
 
     SFstatus = SEL_FILE_CANCEL;
@@ -2703,7 +2686,7 @@ SFcreateWidgets(toplevel, prompt, ok, cancel)
 SFtextChanged()
 {
 #if defined(FEAT_XFONTSET) && defined(XtNinternational)
-    if (_XawTextFormat((TextWidget)selFileField) == XawFmtWide)
+    if ((unsigned long)_XawTextFormat((TextWidget)selFileField) == XawFmtWide)
     {
 	wchar_t *wcbuf=(wchar_t *)SFtextBuffer;
 
@@ -2749,7 +2732,7 @@ SFgetText()
 #if defined(FEAT_XFONTSET) && defined(XtNinternational)
     char *buf;
 
-    if (_XawTextFormat((TextWidget)selFileField) == XawFmtWide)
+    if ((unsigned long)_XawTextFormat((TextWidget)selFileField) == XawFmtWide)
     {
 	wchar_t *wcbuf;
 	int mbslength;
diff --git a/src/gui_at_sb.c b/src/gui_at_sb.c
index 1726953a22..16d8d36fa4 100644
--- a/src/gui_at_sb.c
+++ b/src/gui_at_sb.c
@@ -198,10 +198,13 @@ ScrollbarClassRec vim_scrollbarClassRec =
     /* extension	*/  NULL
   },
   { /* simple fields */
-    /* change_sensitive	*/  XtInheritChangeSensitive
+    /* change_sensitive	*/  XtInheritChangeSensitive,
+#ifndef OLDXAW
+    /* extension */	    NULL
+#endif
   },
   { /* scrollbar fields */
-    /* ignore	    */	0
+    /* empty	    */	    0
   }
 };
 
@@ -241,7 +244,8 @@ FillArea(sbw, top, bottom, fill, draw_shadow)
 
     if (bottom <= 0 || bottom <= top)
 	return;
-    if ((sw = sbw->scrollbar.shadow_width) < 0)
+    sw = sbw->scrollbar.shadow_width;
+    if (sw < 0)
 	sw = 0;
     margin = MARGIN (sbw);
     floor = sbw->scrollbar.length - margin + 2;
@@ -516,13 +520,12 @@ SetDimensions(sbw)
     }
 }
 
-/* ARGSUSED */
     static void
 Initialize(request, new, args, num_args)
-    Widget	request;	/* what the client asked for */
+    Widget	request UNUSED;	/* what the client asked for */
     Widget	new;		/* what we're going to give him */
-    ArgList	args;
-    Cardinal	*num_args;
+    ArgList	args UNUSED;
+    Cardinal	*num_args UNUSED;
 {
     ScrollbarWidget sbw = (ScrollbarWidget) new;
 
@@ -556,14 +559,13 @@ Realize(w, valueMask, attributes)
 	(w, valueMask, attributes);
 }
 
-/* ARGSUSED */
     static Boolean
 SetValues(current, request, desired, args, num_args)
-    Widget  current,	    /* what I am */
-	    request,	    /* what he wants me to be */
-	    desired;	    /* what I will become */
-    ArgList args;
-    Cardinal *num_args;
+    Widget  current;	    /* what I am */
+    Widget  request UNUSED; /* what he wants me to be */
+    Widget  desired;	    /* what I will become */
+    ArgList args UNUSED;
+    Cardinal *num_args UNUSED;
 {
     ScrollbarWidget	sbw = (ScrollbarWidget) current;
     ScrollbarWidget	dsbw = (ScrollbarWidget) desired;
@@ -609,7 +611,6 @@ Resize(w)
 }
 
 
-/* ARGSUSED */
     static void
 Redisplay(w, event, region)
     Widget w;
@@ -789,11 +790,10 @@ HandleThumb(w, event, params, num_params)
     }
 }
 
-/* ARGSUSED */
     static void
 RepeatNotify(client_data, idp)
     XtPointer client_data;
-    XtIntervalId *idp;
+    XtIntervalId *idp UNUSED;
 {
     ScrollbarWidget sbw = (ScrollbarWidget) client_data;
     int		    call_data;
@@ -839,46 +839,42 @@ FloatInRange(num, small, big)
     return (num < small) ? small : ((num > big) ? big : num);
 }
 
-/* ARGSUSED */
     static void
 ScrollOneLineUp(w, event, params, num_params)
     Widget	w;
     XEvent	*event;
-    String	*params;
-    Cardinal	*num_params;
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
     ScrollSome(w, event, -ONE_LINE_DATA);
 }
 
-/* ARGSUSED */
     static void
 ScrollOneLineDown(w, event, params, num_params)
     Widget	w;
     XEvent	*event;
-    String	*params;
-    Cardinal	*num_params;
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
     ScrollSome(w, event, ONE_LINE_DATA);
 }
 
-/* ARGSUSED */
     static void
 ScrollPageDown(w, event, params, num_params)
     Widget	w;
     XEvent	*event;
-    String	*params;
-    Cardinal	*num_params;
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
     ScrollSome(w, event, ONE_PAGE_DATA);
 }
 
-/* ARGSUSED */
     static void
 ScrollPageUp(w, event, params, num_params)
     Widget	w;
     XEvent	*event;
-    String	*params;
-    Cardinal	*num_params;
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
     ScrollSome(w, event, -ONE_PAGE_DATA);
 }
@@ -901,13 +897,12 @@ ScrollSome(w, event, call_data)
     XtCallCallbacks(w, XtNscrollProc, (XtPointer)call_data);
 }
 
-/* ARGSUSED */
     static void
 NotifyScroll(w, event, params, num_params)
     Widget	w;
     XEvent	*event;
-    String	*params;
-    Cardinal	*num_params;
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
     ScrollbarWidget sbw = (ScrollbarWidget) w;
     Position	    x, y, loc;
@@ -991,13 +986,12 @@ NotifyScroll(w, event, params, num_params)
 					   delay, RepeatNotify, (XtPointer)w);
 }
 
-/* ARGSUSED */
     static void
 EndScroll(w, event, params, num_params)
     Widget w;
-    XEvent *event;	/* unused */
-    String *params;	/* unused */
-    Cardinal *num_params;   /* unused */
+    XEvent *event UNUSED;
+    String *params UNUSED;
+    Cardinal *num_params UNUSED;
 {
     ScrollbarWidget sbw = (ScrollbarWidget) w;
 
@@ -1023,13 +1017,12 @@ FractionLoc(sbw, x, y)
     return PICKLENGTH(sbw, x / width, y / height);
 }
 
-/* ARGSUSED */
     static void
 MoveThumb(w, event, params, num_params)
     Widget	w;
     XEvent	*event;
-    String	*params;	/* unused */
-    Cardinal	*num_params;	/* unused */
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
     ScrollbarWidget	sbw = (ScrollbarWidget)w;
     Position		x, y;
@@ -1069,13 +1062,12 @@ MoveThumb(w, event, params, num_params)
 }
 
 
-/* ARGSUSED */
     static void
 NotifyThumb(w, event, params, num_params)
     Widget	w;
     XEvent	*event;
-    String	*params;	/* unused */
-    Cardinal	*num_params;	/* unused */
+    String	*params UNUSED;
+    Cardinal	*num_params UNUSED;
 {
     ScrollbarWidget sbw = (ScrollbarWidget)w;
     /* Use a union to avoid a warning for the weird conversion from float to
@@ -1096,7 +1088,6 @@ NotifyThumb(w, event, params, num_params)
     XtCallCallbacks(w, XtNjumpProc, (XtPointer)&sbw->scrollbar.top);
 }
 
-/* ARGSUSED */
     static void
 AllocTopShadowGC(w)
     Widget w;
@@ -1110,7 +1101,6 @@ AllocTopShadowGC(w)
     sbw->scrollbar.top_shadow_GC = XtGetGC(w, valuemask, &myXGCV);
 }
 
-/* ARGSUSED */
     static void
 AllocBotShadowGC(w)
     Widget w;
@@ -1124,11 +1114,10 @@ AllocBotShadowGC(w)
     sbw->scrollbar.bot_shadow_GC = XtGetGC(w, valuemask, &myXGCV);
 }
 
-/* ARGSUSED */
     static void
 _Xaw3dDrawShadows(gw, event, region, out)
     Widget  gw;
-    XEvent  *event;
+    XEvent  *event UNUSED;
     Region  region;
     int	    out;
 {
diff --git a/src/gui_athena.c b/src/gui_athena.c
index c86703eebb..f5b8f70f9b 100644
--- a/src/gui_athena.c
+++ b/src/gui_athena.c
@@ -86,10 +86,9 @@ static int		puller_width = 0;
  * Scrollbar callback (XtNjumpProc) for when the scrollbar is dragged with the
  * left or middle mouse button.
  */
-/* ARGSUSED */
     static void
 gui_athena_scroll_cb_jump(w, client_data, call_data)
-    Widget	w;
+    Widget	w UNUSED;
     XtPointer	client_data, call_data;
 {
     scrollbar_T *sb, *sb_info;
@@ -122,10 +121,9 @@ gui_athena_scroll_cb_jump(w, client_data, call_data)
  * Scrollbar callback (XtNscrollProc) for paging up or down with the left or
  * right mouse buttons.
  */
-/* ARGSUSED */
     static void
 gui_athena_scroll_cb_scroll(w, client_data, call_data)
-    Widget	w;
+    Widget	w UNUSED;
     XtPointer	client_data, call_data;
 {
     scrollbar_T *sb, *sb_info;
@@ -492,7 +490,7 @@ get_toolbar_pixmap(menu, sen)
     if (menu->icon_builtin || gui_find_bitmap(menu->name, buf, "xpm") == FAIL)
     {
 	if (menu->iconidx >= 0 && menu->iconidx
-		   < (sizeof(built_in_pixmaps) / sizeof(built_in_pixmaps[0])))
+	      < (int)(sizeof(built_in_pixmaps) / sizeof(built_in_pixmaps[0])))
 	    xpm = built_in_pixmaps[menu->iconidx];
 	else
 	    xpm = tb_blank_xpm;
@@ -763,7 +761,7 @@ athena_calculate_ins_pos(widget)
     XtGetValues(XtParent(widget), args, n);
 
     retval = num_children;
-    for (i = 0; i < num_children; ++i)
+    for (i = 0; i < (int)num_children; ++i)
     {
 	Widget	current = children[i];
 	vimmenu_T	*menu = NULL;
@@ -780,11 +778,10 @@ athena_calculate_ins_pos(widget)
     return retval;
 }
 
-/* ARGSUSED */
     void
 gui_mch_add_menu(menu, idx)
     vimmenu_T	*menu;
-    int		idx;
+    int		idx UNUSED;
 {
     char_u	*pullright_name;
     Dimension	height, space, border;
@@ -869,7 +866,7 @@ gui_mch_add_menu(menu, idx)
 	    XtVaGetValues(parent->submenu_id, XtNchildren, &children,
 					      XtNnumChildren, &num_children,
 					      NULL);
-	    for (i = 0; i < num_children; ++i)
+	    for (i = 0; i < (int)num_children; ++i)
 	    {
 		XtVaSetValues(children[i],
 			      XtNrightMargin, puller_width,
@@ -913,7 +910,7 @@ gui_athena_menu_has_submenus(id, ignore)
     XtVaGetValues(id, XtNchildren, &children,
 		      XtNnumChildren, &num_children,
 		      NULL);
-    for (i = 0; i < num_children; ++i)
+    for (i = 0; i < (int)num_children; ++i)
     {
 	if (children[i] == ignore)
 	    continue;
@@ -1175,11 +1172,10 @@ make_pull_name(name)
     return pname;
 }
 
-/* ARGSUSED */
     void
 gui_mch_add_menu_item(menu, idx)
     vimmenu_T	*menu;
-    int		idx;
+    int		idx UNUSED;
 {
     vimmenu_T	*parent = menu->parent;
 
@@ -1444,7 +1440,7 @@ gui_mch_compute_toolbar_height()
 		XtNchildren,	    &children,
 		XtNnumChildren,	    &numChildren,
 		NULL);
-	for (i = 0; i < numChildren; i++)
+	for (i = 0; i < (int)numChildren; i++)
 	{
 	    whgt = 0;
 
@@ -1473,10 +1469,9 @@ gui_mch_get_toolbar_colors(bgp, fgp, bsp, tsp, hsp)
 #endif
 
 
-/* ARGSUSED */
     void
 gui_mch_toggle_tearoffs(enable)
-    int		enable;
+    int		enable UNUSED;
 {
     /* no tearoff menus */
 }
@@ -1537,7 +1532,7 @@ gui_mch_destroy_menu(menu)
 	    else
 		get_left_margin = True;
 
-	    for (i = 0; i < num_children; ++i)
+	    for (i = 0; i < (int)num_children; ++i)
 	    {
 		if (children[i] == menu->id)
 		    continue;
@@ -1645,11 +1640,10 @@ gui_mch_destroy_menu(menu)
     }
 }
 
-/*ARGSUSED*/
     static void
 gui_athena_menu_timeout(client_data, id)
     XtPointer	    client_data;
-    XtIntervalId    *id;
+    XtIntervalId    *id UNUSED;
 {
     Widget  w = (Widget)client_data;
     Widget  popup;
@@ -1678,12 +1672,11 @@ gui_athena_menu_timeout(client_data, id)
  *
  * This is called when XtPopup() is called.
  */
-/*ARGSUSED*/
     static void
 gui_athena_popup_callback(w, client_data, call_data)
     Widget	w;
     XtPointer	client_data;
-    XtPointer	call_data;
+    XtPointer	call_data UNUSED;
 {
     /* Assumption: XtIsSubclass(XtParent(w),simpleMenuWidgetClass) */
     vimmenu_T	*menu = (vimmenu_T *)client_data;
@@ -1711,7 +1704,6 @@ gui_athena_popup_callback(w, client_data, call_data)
 		     NULL);
 }
 
-/* ARGSUSED */
     static void
 gui_athena_popdown_submenus_action(w, event, args, nargs)
     Widget	w;
@@ -1756,7 +1748,6 @@ has_submenu(widget)
     return False;
 }
 
-/* ARGSUSED */
     static void
 gui_athena_delayed_arm_action(w, event, args, nargs)
     Widget	w;
@@ -1837,7 +1828,6 @@ submenu_widget(widget)
      * (XtIsSubclass(popup,simpleMenuWidgetClass) == True) */
 }
 
-/* ARGSUSED */
     void
 gui_mch_show_popupmenu(menu)
     vimmenu_T *menu;
@@ -2046,15 +2036,14 @@ gui_x11_get_wid()
  * Put up a file requester.
  * Returns the selected name in allocated memory, or NULL for Cancel.
  */
-/* ARGSUSED */
     char_u *
 gui_mch_browse(saving, title, dflt, ext, initdir, filter)
-    int		saving;		/* select file to write */
-    char_u	*title;		/* not used (title for the window) */
-    char_u	*dflt;		/* not used (default name) */
-    char_u	*ext;		/* not used (extension added) */
+    int		saving UNUSED;	/* select file to write */
+    char_u	*title;		/* title for the window */
+    char_u	*dflt;		/* default name */
+    char_u	*ext UNUSED;	/* extension added */
     char_u	*initdir;	/* initial directory, NULL for current dir */
-    char_u	*filter;	/* not used (file name filter) */
+    char_u	*filter UNUSED;	/* file name filter */
 {
     Position x, y;
     char_u	dirbuf[MAXPATHL];
@@ -2100,13 +2089,12 @@ static void dialog_wm_handler __ARGS((Widget w, XtPointer client_data, XEvent *e
  * Callback function for the textfield.  When CR is hit this works like
  * hitting the "OK" button, ESC like "Cancel".
  */
-/* ARGSUSED */
     static void
 keyhit_callback(w, client_data, event, cont)
-    Widget		w;
-    XtPointer		client_data;
+    Widget		w UNUSED;
+    XtPointer		client_data UNUSED;
     XEvent		*event;
-    Boolean		*cont;
+    Boolean		*cont UNUSED;
 {
     char	buf[2];
 
@@ -2119,12 +2107,11 @@ keyhit_callback(w, client_data, event, cont)
     }
 }
 
-/* ARGSUSED */
     static void
 butproc(w, client_data, call_data)
-    Widget	w;
+    Widget	w UNUSED;
     XtPointer	client_data;
-    XtPointer	call_data;
+    XtPointer	call_data UNUSED;
 {
     dialogStatus = (int)(long)client_data + 1;
 }
@@ -2132,27 +2119,25 @@ butproc(w, client_data, call_data)
 /*
  * Function called when dialog window closed.
  */
-/*ARGSUSED*/
     static void
 dialog_wm_handler(w, client_data, event, dum)
-    Widget	w;
-    XtPointer	client_data;
+    Widget	w UNUSED;
+    XtPointer	client_data UNUSED;
     XEvent	*event;
-    Boolean	*dum;
+    Boolean	*dum UNUSED;
 {
     if (event->type == ClientMessage
-	    && ((XClientMessageEvent *)event)->data.l[0] == dialogatom)
+	    && (Atom)((XClientMessageEvent *)event)->data.l[0] == dialogatom)
 	dialogStatus = 0;
 }
 
-/* ARGSUSED */
     int
 gui_mch_dialog(type, title, message, buttons, dfltbutton, textfield)
-    int		type;
+    int		type UNUSED;
     char_u	*title;
     char_u	*message;
     char_u	*buttons;
-    int		dfltbutton;
+    int		dfltbutton UNUSED;
     char_u	*textfield;
 {
     char_u		*buts;
diff --git a/src/gui_beval.c b/src/gui_beval.c
index 796103c730..123b6fd1b7 100644
--- a/src/gui_beval.c
+++ b/src/gui_beval.c
@@ -18,7 +18,7 @@
     void
 general_beval_cb(beval, state)
     BalloonEval *beval;
-    int state;
+    int		state UNUSED;
 {
     win_T	*wp;
     int		col;
@@ -726,10 +726,10 @@ removeEventHandler(beval)
  */
     static void
 pointerEventEH(w, client_data, event, unused)
-    Widget	w;
+    Widget	w UNUSED;
     XtPointer	client_data;
     XEvent	*event;
-    Boolean	*unused;
+    Boolean	*unused UNUSED;
 {
     BalloonEval *beval = (BalloonEval *)client_data;
     pointerEvent(beval, event);
@@ -877,7 +877,7 @@ pointerEvent(beval, event)
     static void
 timerRoutine(dx, id)
     XtPointer	    dx;
-    XtIntervalId    *id;
+    XtIntervalId    *id UNUSED;
 {
     BalloonEval *beval = (BalloonEval *)dx;
 
diff --git a/src/gui_motif.c b/src/gui_motif.c
index 8285b16741..9458e4d7d9 100644
--- a/src/gui_motif.c
+++ b/src/gui_motif.c
@@ -117,10 +117,9 @@ static void gui_motif_scroll_colors __ARGS((Widget id));
  * Call-back routines.
  */
 
-/* ARGSUSED */
     static void
 scroll_cb(w, client_data, call_data)
-    Widget	w;
+    Widget	w UNUSED;
     XtPointer	client_data, call_data;
 {
     scrollbar_T *sb;
@@ -136,11 +135,11 @@ scroll_cb(w, client_data, call_data)
 }
 
 #ifdef FEAT_GUI_TABLINE
-/*ARGSUSED*/
     static void
 tabline_cb(w, client_data, call_data)
-    Widget	w;
-    XtPointer	client_data, call_data;
+    Widget	w UNUSED;
+    XtPointer	client_data UNUSED;
+    XtPointer	call_data;
 {
     XmNotebookCallbackStruct *nptr;
 
@@ -149,11 +148,11 @@ tabline_cb(w, client_data, call_data)
 	send_tabline_event(nptr->page_number);
 }
 
-/*ARGSUSED*/
     static void
 tabline_button_cb(w, client_data, call_data)
     Widget	w;
-    XtPointer	client_data, call_data;
+    XtPointer	client_data UNUSED;
+    XtPointer	call_data UNUSED;
 {
     int		cmd, tab_idx;
 
@@ -166,11 +165,10 @@ tabline_button_cb(w, client_data, call_data)
 /*
  * Tabline single mouse click timeout handler
  */
-/*ARGSUSED*/
     static void
 motif_tabline_timer_cb (timed_out, interval_id)
     XtPointer		timed_out;
-    XtIntervalId	*interval_id;
+    XtIntervalId	*interval_id UNUSED;
 {
     *((int *)timed_out) = TRUE;
 }
@@ -203,13 +201,12 @@ tabline_scroller_clicked(scroller_name, event)
     return FALSE;
 }
 
-/*ARGSUSED*/
     static void
 tabline_menu_cb(w, closure, e, continue_dispatch)
     Widget	w;
-    XtPointer	closure;
+    XtPointer	closure UNUSED;
     XEvent	*e;
-    Boolean	*continue_dispatch;
+    Boolean	*continue_dispatch UNUSED;
 {
     Widget			tab_w;
     XButtonPressedEvent		*event;
@@ -277,11 +274,10 @@ tabline_menu_cb(w, closure, e, continue_dispatch)
     XtManageChild(tabLine_menu);
 }
 
-/*ARGSUSED*/
     static void
 tabline_balloon_cb(beval, state)
     BalloonEval	*beval;
-    int		state;
+    int		state UNUSED;
 {
     int		nr;
     tabpage_T	*tp;
@@ -642,13 +638,12 @@ gui_x11_destroy_widgets()
 #endif
 }
 
-/*ARGSUSED*/
     void
 gui_mch_set_text_area_pos(x, y, w, h)
-    int	    x;
-    int	    y;
-    int	    w;
-    int	    h;
+    int	    x UNUSED;
+    int	    y UNUSED;
+    int	    w UNUSED;
+    int	    h UNUSED;
 {
 #ifdef FEAT_TOOLBAR
     /* Give keyboard focus to the textArea instead of the toolbar. */
@@ -1261,7 +1256,7 @@ get_toolbar_pixmap(menu, fname)
     if (menu->icon_builtin || gui_find_bitmap(menu->name, buf, "xpm") == FAIL)
     {
 	if (menu->iconidx >= 0 && menu->iconidx
-		   < (sizeof(built_in_pixmaps) / sizeof(built_in_pixmaps[0])))
+	       < (int)(sizeof(built_in_pixmaps) / sizeof(built_in_pixmaps[0])))
 	    xpm = built_in_pixmaps[menu->iconidx];
 	else
 	    xpm = tb_blank_xpm;
@@ -1716,10 +1711,9 @@ gui_mch_destroy_menu(menu)