(svn r8178) -Backport from turnk (r8049, r8079, r8080, r8135):

- oe more news-window fix and fix up ShowLastNewsMessage (r8049)
 - float division by 0 in YAPF code on Win9x (r8079, r8080)
 - do not assert when removing duplicates would remove non-static grf (r8135)

newgrf_config.c

@@ -158,7 +158,7 @@ static void RemoveDuplicatesFromGRFConfigList(GRFConfig *list)
 
 	for (prev = list, cur = list->next; cur != NULL; prev = cur, cur = cur->next) {
 		if (cur->grfid != list->grfid) continue;
-		assert(HASBIT(cur->flags, GCF_STATIC));
+
 		prev->next = cur->next;
 		ClearGRFConfig(&cur);
 		cur = prev; // Just go back one so it continues as normal later on

news_gui.c

@@ -272,7 +272,6 @@ void AddNewsItem(StringID string, uint32 flags, uint data_a, uint data_b)
 	if (_total_news == MAX_NEWS && (_oldest_news == _current_news || _oldest_news == _forced_news))
 		MoveToNextItem();
 
-	_forced_news = INVALID_NEWS;
 	if (_total_news < MAX_NEWS) _total_news++;
 
 	/* Increase _latest_news. If we have no news yet, use _oldest news as an
@@ -555,16 +554,17 @@ static void ShowNewsMessage(NewsID i)
 
 void ShowLastNewsMessage(void)
 {
-	switch (_forced_news) {
+	if (_forced_news == INVALID_NEWS) {
-		case INVALID_NEWS: // Not forced any news yet, show the current one
+		/* Not forced any news yet, show the current one, unless a news window is
-			ShowNewsMessage(_current_news);
+		 * open (which can only be the current one), then show the previous item */
-			break;
+		const Window *w = FindWindowById(WC_NEWS_WINDOW, 0);
-		case 0: //
+		ShowNewsMessage((w == NULL) ? _current_news : decreaseIndex(_current_news));
-			ShowNewsMessage(_total_news != MAX_NEWS ? _latest_news : MAX_NEWS - 1);
+	} else if (_forced_news == _oldest_news) {
-			break;
+		/* We have reached the oldest news, start anew with the latest */
-		default: // 'Scrolling' through news history show each one in turn
+		ShowNewsMessage(_latest_news);
-			ShowNewsMessage(_forced_news - 1);
+	} else {
-			break;
+		/* 'Scrolling' through news history show each one in turn */
+		ShowNewsMessage(decreaseIndex(_forced_news));
 	}
 }
 
@@ -889,7 +889,10 @@ void DeleteVehicleNews(VehicleID vid, StringID news)
 				(news == INVALID_STRING_ID || ni->string_id == news)) {
 			Window *w;
 
-			if (_forced_news == n || _current_news == n) MoveToNextItem();
+			/* If we delete a forced news and it is just before the current news
+			 * then we need to advance to the next news (if any) */
+			if (_forced_news == n) MoveToNextItem();
+			if (_forced_news == INVALID_NEWS && _current_news == n) MoveToNextItem();
 			_total_news--;
 
 			/* If this is the last news item, invalidate _latest_news */
@@ -908,7 +911,7 @@ void DeleteVehicleNews(VehicleID vid, StringID news)
 			 * We also need an update of the current, forced and visible (open window)
 			 * news's as this shifting could change the items they were pointing to */
 			if (_total_news != 0) {
-				NewsID i, visible_news;
+				NewsID visible_news, i;
 				w = FindWindowById(WC_NEWS_WINDOW, 0);
 				visible_news = (w != NULL) ? (NewsID)(WP(w, news_d).ni - _news_items) : INVALID_NEWS;
 

yapf/yapf_base.hpp

@@ -106,19 +106,21 @@ public:
 	 *      - or the open list is empty (no route to destination).
 	 *      - or the maximum amount of loops reached - m_max_search_nodes (default = 10000)
 	 * @return true if the path was found */
-	inline bool FindPath(const Vehicle* v)
+	inline bool FindPath(const Vehicle *v)
 	{
 		m_veh = v;
 
+#ifndef NO_DEBUG_MESSAGES
 		CPerformanceTimer perf;
 		perf.Start();
+#endif /* !NO_DEBUG_MESSAGES */
+
 		Yapf().PfSetStartupNodes();
 
 		while (true) {
 			m_num_steps++;
-			Node* n = m_nodes.GetBestOpenNode();
+			Node *n = m_nodes.GetBestOpenNode();
-			if (n == NULL)
+			if (n == NULL) break;
-				break;
 
 			// if the best open node was worse than the best path found, we can finish
 			if (m_pBestDestNode != NULL && m_pBestDestNode->GetCost() < n->GetCostEstimate())
@@ -135,18 +137,25 @@ public:
 		}
 		bool bDestFound = (m_pBestDestNode != NULL);
 
-		int16 veh_idx = (m_veh != NULL) ? m_veh->unitnumber : 0;
+#ifndef NO_DEBUG_MESSAGES
-
-//		if (veh_idx != 433) return bDestFound;
-
 		perf.Stop();
+		if (_debug_yapf_level >= 3) {
 			int t = perf.Get(1000000);
 			_total_pf_time_us += t;
+
+			UnitID veh_idx = (m_veh != NULL) ? m_veh->unitnumber : 0;
 			char ttc = Yapf().TransportTypeChar();
-		float cache_hit_ratio = (float)m_stats_cache_hits / (float)(m_stats_cache_hits + m_stats_cost_calcs) * 100.0f;
+			float cache_hit_ratio = (m_stats_cache_hits == 0) ? 0.0f : ((float)m_stats_cache_hits / (float)(m_stats_cache_hits + m_stats_cost_calcs) * 100.0f);
 			int cost = bDestFound ? m_pBestDestNode->m_cost : -1;
 			int dist = bDestFound ? m_pBestDestNode->m_estimate - m_pBestDestNode->m_cost : -1;
-		DEBUG(yapf, 3)("[YAPF][YAPF%c]%c%4d- %d us - %d rounds - %d open - %d closed - CHR %4.1f%% - c%d(sc%d, ts%d, o%d) -- ", ttc, bDestFound ? '-' : '!', veh_idx, t, m_num_steps, m_nodes.OpenCount(), m_nodes.ClosedCount(), cache_hit_ratio, cost, dist, m_perf_cost.Get(1000000), m_perf_slope_cost.Get(1000000), m_perf_ts_cost.Get(1000000), m_perf_other_cost.Get(1000000));
+
+			DEBUG(yapf, 3) ("[YAPF%c]%c%4d- %d us - %d rounds - %d open - %d closed - CHR %4.1f%% - c%d(sc%d, ts%d, o%d) -- ",
+			  ttc, bDestFound ? '-' : '!', veh_idx, t, m_num_steps, m_nodes.OpenCount(), m_nodes.ClosedCount(),
+			  cache_hit_ratio, cost, dist, m_perf_cost.Get(1000000), m_perf_slope_cost.Get(1000000),
+			  m_perf_ts_cost.Get(1000000), m_perf_other_cost.Get(1000000)
+			);
+		}
+#endif /* !NO_DEBUG_MESSAGES */
 		return bDestFound;
 	}