Merge branch 'pr616' into NetHack-3.7

doc/fixes37.0

@@ -1314,6 +1314,7 @@ MAX_RADIUS defines the outer bound of the radius table, so leave it at 15
 	(pr #613 by argrath) 
 variable attknum was declared without initialization, and was used in
 	find_roll_to_hit() (pr #615 by argrath)
+check for NULL lua_State before calling lua_close() (pr #616 by argrath)
 
 
 Code Cleanup and Reorganization

src/nhlua.c

@@ -1375,7 +1375,8 @@ nhl_init(void)
 void
 nhl_done(lua_State *L)
 {
-    lua_close(L);
+    if (L)
+        lua_close(L);
     iflags.in_lua = FALSE;
 }