Fix:

error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]

https://sourceforge.net/p/vtwm/discussion/936866/thread/4a1d110e12/
--- add_window.c.orig	2018-04-21 00:39:31.000000000 -0500
+++ add_window.c	2024-08-08 01:33:01.000000000 -0500
@@ -457,9 +457,9 @@
   if (Scr->StormPositioning && HandlingEvents == TRUE &&
       !(tmp_win->hints.flags & USPosition) && (tmp_win->group != tmp_win->w))
   {
-    static lastwingroup = 0;
-    static lastwin = 0;
-    static lasttime = 0;
+    static int lastwingroup = 0;
+    static int lastwin = 0;
+    static int lasttime = 0;
     int curtime = time(NULL);
     Window junk;