(svn r27893) -Codechange: Use fallthrough attribute. (LordAro)

60 files changed, 221 insertions, 121 deletions

diff --git a/src/3rdparty/squirrel/squirrel/sqvm.cpp b/src/3rdparty/squirrel/squirrel/sqvm.cpp
index 973002b49..a738244ba 100644
--- a/src/3rdparty/squirrel/squirrel/sqvm.cpp
+++ b/src/3rdparty/squirrel/squirrel/sqvm.cpp
@@ -215,7 +215,7 @@ bool SQVM::ObjCmp(const SQObjectPtr &o1,const SQObjectPtr &o2,SQInteger &result)
 					_RET_SUCCEED(_integer(res))
 				}
 			}
-			//continues through (no break needed)
+			FALLTHROUGH;
 		default:
 			_RET_SUCCEED( _userpointer(o1) < _userpointer(o2)?-1:1 );
 		}
@@ -287,6 +287,7 @@ void SQVM::ToString(const SQObjectPtr &o,SQObjectPtr &res)
 				//else keeps going to the default
 			}
 		}
+		FALLTHROUGH;
 	default:
 		seprintf(buf, lastof(buf),"(%s : 0x%p)",GetTypeName(o),(void*)_rawval(o));
 	}
@@ -539,7 +540,7 @@ bool SQVM::FOREACH_OP(SQObjectPtr &o1,SQObjectPtr &o2,SQObjectPtr
 			_generator(o1)->Resume(this, arg_2+1);
 			_FINISH(0);
 		}
-		/* FALL THROUGH */
+		FALLTHROUGH;
 	default:
 		Raise_Error("cannot iterate %s", GetTypeName(o1));
 	}
@@ -769,7 +770,7 @@ exception_restore:
 					ct_stackbase = _stackbase;
 					goto common_call;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
 			case _OP_CALL: {
 					ct_tailcall = false;
 					ct_target = arg0;
@@ -1330,7 +1331,7 @@ bool SQVM::Set(const SQObjectPtr &self,const SQObjectPtr &key,const SQObjectPtr
 				return true;
 			}
 		}
-		//keeps going
+		FALLTHROUGH;
 	case OT_USERDATA:
 		if(_delegable(self)->_delegate) {
 			SQObjectPtr t;
diff --git a/src/ai/ai_scanner.cpp b/src/ai/ai_scanner.cpp
index 4eb207147..5f16de3f9 100644
--- a/src/ai/ai_scanner.cpp
+++ b/src/ai/ai_scanner.cpp
@@ -114,7 +114,7 @@ AIInfo *AIScannerInfo::FindInfo(const char *nameParam, int versionParam, bool fo
 		*e = '\0';
 		e++;
 		versionParam = atoi(e);
-		/* FALL THROUGH, like we were calling this function with a version. */
+		/* Continue, like we were calling this function with a version. */
 	}
 
 	if (force_exact_match) {
diff --git a/src/company_cmd.cpp b/src/company_cmd.cpp
index 577ea884d..ee2ed1335 100644
--- a/src/company_cmd.cpp
+++ b/src/company_cmd.cpp
@@ -162,7 +162,7 @@ static bool IsValidCompanyManagerFace(CompanyManagerFace cmf)
 	for (CompanyManagerFaceVariable cmfv = CMFV_CHEEKS; cmfv < CMFV_END; cmfv++) {
 		switch (cmfv) {
 			case CMFV_MOUSTACHE:   if (!has_moustache)   continue; break;
-			case CMFV_LIPS:        // FALL THROUGH
+			case CMFV_LIPS:
 			case CMFV_NOSE:        if (has_moustache)    continue; break;
 			case CMFV_TIE_EARRING: if (!has_tie_earring) continue; break;
 			case CMFV_GLASSES:     if (!has_glasses)     continue; break;
diff --git a/src/company_gui.cpp b/src/company_gui.cpp
index 4d394203d..31d4fdd1f 100644
--- a/src/company_gui.cpp
+++ b/src/company_gui.cpp
@@ -318,7 +318,8 @@ struct CompanyFinancesWindow : Window {
 			case WID_CF_EXPS_PRICE2:
 			case WID_CF_EXPS_PRICE3:
 				size->height = _expenses_list_types[type].GetHeight();
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case WID_CF_BALANCE_VALUE:
 			case WID_CF_LOAN_VALUE:
 			case WID_CF_TOTAL_VALUE:
@@ -636,7 +637,8 @@ public:
 					size->width = 0;
 					break;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case WID_SCL_PRI_COL_DROPDOWN: {
 				int padding = this->square.width + NWidgetScrollbar::GetVerticalDimension().width + 10;
 				for (const StringID *id = _colour_dropdown; id != endof(_colour_dropdown); id++) {
@@ -892,7 +894,7 @@ void DrawCompanyManagerFace(CompanyManagerFace cmf, int colour, int x, int y)
 	for (CompanyManagerFaceVariable cmfv = CMFV_CHEEKS; cmfv < CMFV_END; cmfv++) {
 		switch (cmfv) {
 			case CMFV_MOUSTACHE:   if (!has_moustache)   continue; break;
-			case CMFV_LIPS:        // FALL THROUGH
+			case CMFV_LIPS:
 			case CMFV_NOSE:        if (has_moustache)    continue; break;
 			case CMFV_TIE_EARRING: if (!has_tie_earring) continue; break;
 			case CMFV_GLASSES:     if (!has_glasses)     continue; break;
@@ -1365,7 +1367,7 @@ public:
 			/* OK button */
 			case WID_SCMF_ACCEPT:
 				DoCommandP(0, 0, this->face, CMD_SET_COMPANY_MANAGER_FACE);
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			/* Cancel button */
 			case WID_SCMF_CANCEL:
diff --git a/src/console.cpp b/src/console.cpp
index ece859916..6e9b46f6b 100644
--- a/src/console.cpp
+++ b/src/console.cpp
@@ -468,7 +468,7 @@ void IConsoleCmdExec(const char *cmdstr)
 				tokenstream[tstream_i++] = *++cmdptr;
 				break;
 			}
-			/* FALL THROUGH */
+			FALLTHROUGH;
 		default: // Normal character
 			tokenstream[tstream_i++] = *cmdptr;
 
diff --git a/src/depot_gui.cpp b/src/depot_gui.cpp
index 47eefc65e..a99f2e4dd 100644
--- a/src/depot_gui.cpp
+++ b/src/depot_gui.cpp
@@ -445,7 +445,8 @@ struct DepotWindow : Window {
 			switch (this->type) {
 				case VEH_TRAIN:
 					if (wagon) return MODE_ERROR;
-					/* FALL THROUGH */
+					FALLTHROUGH;
+
 				case VEH_ROAD:
 					if (xm <= this->flag_width) return MODE_START_STOP;
 					break;
diff --git a/src/economy.cpp b/src/economy.cpp
index 7461d34b7..0106e87e1 100644
--- a/src/economy.cpp
+++ b/src/economy.cpp
@@ -1726,7 +1726,7 @@ static void LoadUnloadVehicle(Vehicle *front)
 		/* update stats */
 		int t;
 		switch (front->type) {
-			case VEH_TRAIN: /* FALL THROUGH */
+			case VEH_TRAIN:
 			case VEH_SHIP:
 				t = front->vcache.cached_max_speed;
 				break;
diff --git a/src/engine_gui.cpp b/src/engine_gui.cpp
index d1ccd3bf4..5e9e8cef7 100644
--- a/src/engine_gui.cpp
+++ b/src/engine_gui.cpp
@@ -126,7 +126,7 @@ struct EnginePreviewWindow : Window {
 		switch (widget) {
 			case WID_EP_YES:
 				DoCommandP(0, this->window_number, 0, CMD_WANT_ENGINE_PREVIEW);
-				/* FALL THROUGH */
+				FALLTHROUGH;
 			case WID_EP_NO:
 				if (!_shift_pressed) delete this;
 				break;
diff --git a/src/fileio.cpp b/src/fileio.cpp
index 085c2c66d..526f5b184 100644
--- a/src/fileio.cpp
+++ b/src/fileio.cpp
@@ -522,7 +522,7 @@ FILE *FioFOpenFile(const char *filename, const char *mode, Subdirectory subdir,
 			case BASESET_DIR:
 				f = FioFOpenFile(filename, mode, OLD_GM_DIR, filesize);
 				if (f != NULL) break;
-				/* FALL THROUGH */
+				FALLTHROUGH;
 			case NEWGRF_DIR:
 				f = FioFOpenFile(filename, mode, OLD_DATA_DIR, filesize);
 				break;
@@ -1477,7 +1477,7 @@ uint FileScanner::Scan(const char *extension, Subdirectory sd, bool tars, bool r
 	switch (sd) {
 		case BASESET_DIR:
 			num += this->Scan(extension, OLD_GM_DIR, tars, recursive);
-			/* FALL THROUGH */
+			FALLTHROUGH;
 		case NEWGRF_DIR:
 			num += this->Scan(extension, OLD_DATA_DIR, tars, recursive);
 			break;
diff --git a/src/fios.cpp b/src/fios.cpp
index 8ed01152f..0d30e0965 100644
--- a/src/fios.cpp
+++ b/src/fios.cpp
@@ -158,7 +158,8 @@ const char *FiosBrowseTo(const FiosItem *item)
 #elif defined(WIN32) || defined(__OS2__)
 			seprintf(_fios_path, _fios_path_last, "%c:" PATHSEP, item->title[0]);
 #endif
-			/* FALL THROUGH */
+			break;
+
 		case FIOS_TYPE_INVALID:
 			break;
 
diff --git a/src/fios_gui.cpp b/src/fios_gui.cpp
index e6cd9625c..f20cfd792 100644
--- a/src/fios_gui.cpp
+++ b/src/fios_gui.cpp
@@ -702,7 +702,8 @@ public:
 				this->vscroll->SetCount(this->fios_items.Length());
 				this->selected = NULL;
 				_load_check_data.Clear();
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case 1:
 				/* Selection changes */
 				if (!gui_scope) break;
diff --git a/src/fontcache.cpp b/src/fontcache.cpp
index 85e5a92cc..72e42ccbb 100644
--- a/src/fontcache.cpp
+++ b/src/fontcache.cpp
@@ -126,7 +126,7 @@ void SpriteFontCache::InitializeUnicodeGlyphMap()
 	SpriteID base;
 	switch (this->fs) {
 		default: NOT_REACHED();
-		case FS_MONO:   // Use normal as default for mono spaced font, i.e. FALL THROUGH
+		case FS_MONO:   // Use normal as default for mono spaced font
 		case FS_NORMAL: base = SPR_ASCII_SPACE;       break;
 		case FS_SMALL:  base = SPR_ASCII_SPACE_SMALL; break;
 		case FS_LARGE:  base = SPR_ASCII_SPACE_BIG;   break;
diff --git a/src/game/game_scanner.cpp b/src/game/game_scanner.cpp
index bc02f6afd..38afdd135 100644
--- a/src/game/game_scanner.cpp
+++ b/src/game/game_scanner.cpp
@@ -55,7 +55,7 @@ GameInfo *GameScannerInfo::FindInfo(const char *nameParam, int versionParam, boo
 		*e = '\0';
 		e++;
 		versionParam = atoi(e);
-		/* FALL THROUGH, like we were calling this function with a version. */
+		/* Continue like we were calling this function with a version. */
 	}
 
 	if (force_exact_match) {
diff --git a/src/industry_gui.cpp b/src/industry_gui.cpp
index b9077b9d7..41b3c573f 100644
--- a/src/industry_gui.cpp
+++ b/src/industry_gui.cpp
@@ -785,7 +785,7 @@ public:
 						DrawString(left_side, right - WD_FRAMERECT_RIGHT, y, STR_INDUSTRY_VIEW_ACCEPT_CARGO_AMOUNT);
 						break;
 					}
-					/* FALL THROUGH */
+					FALLTHROUGH;
 
 				case CSD_CARGO:
 					SetDParam(0, CargoSpec::Get(i->accepts_cargo[j])->name);
diff --git a/src/misc_gui.cpp b/src/misc_gui.cpp
index 2d3871ffb..03500c2a2 100644
--- a/src/misc_gui.cpp
+++ b/src/misc_gui.cpp
@@ -1007,10 +1007,12 @@ struct QueryStringWindow : public Window
 		switch (widget) {
 			case WID_QS_DEFAULT:
 				this->editbox.text.DeleteAll();
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case WID_QS_OK:
 				this->OnOk();
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case WID_QS_CANCEL:
 				delete this;
 				break;
@@ -1160,7 +1162,8 @@ struct QueryWindow : public Window {
 					this->proc(this->parent, true);
 					this->proc = NULL;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case WKC_ESC:
 				delete this;
 				return ES_HANDLED;
diff --git a/src/music/extmidi.cpp b/src/music/extmidi.cpp
index 12b3689e2..d39a050f6 100644
--- a/src/music/extmidi.cpp
+++ b/src/music/extmidi.cpp
@@ -124,7 +124,7 @@ void MusicDriver_ExtMidi::DoPlay()
 
 		case -1:
 			DEBUG(driver, 0, "extmidi: couldn't fork: %s", strerror(errno));
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		default:
 			this->song[0] = '\0';
diff --git a/src/music/qtmidi.cpp b/src/music/qtmidi.cpp
index dfd6f16eb..9bc6a6174 100644
--- a/src/music/qtmidi.cpp
+++ b/src/music/qtmidi.cpp
@@ -242,7 +242,7 @@ void MusicDriver_QtMidi::Stop()
 
 		case QT_STATE_PLAY:
 			StopSong();
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case QT_STATE_STOP:
 			DisposeMovie(_quicktime_movie);
@@ -267,13 +267,13 @@ void MusicDriver_QtMidi::PlaySong(const char *filename)
 		case QT_STATE_PLAY:
 			StopSong();
 			DEBUG(driver, 3, "qtmidi: previous tune stopped");
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case QT_STATE_STOP:
 			DisposeMovie(_quicktime_movie);
 			DEBUG(driver, 3, "qtmidi: previous tune disposed");
 			_quicktime_state = QT_STATE_IDLE;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case QT_STATE_IDLE:
 			LoadMovieForMIDIFile(filename, &_quicktime_movie);
@@ -294,7 +294,7 @@ void MusicDriver_QtMidi::StopSong()
 
 	switch (_quicktime_state) {
 		case QT_STATE_IDLE:
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case QT_STATE_STOP:
 			DEBUG(driver, 3, "qtmidi: stop requested, but already idle");
diff --git a/src/network/core/udp.cpp b/src/network/core/udp.cpp
index ce5f06b1f..20b1ce119 100644
--- a/src/network/core/udp.cpp
+++ b/src/network/core/udp.cpp
@@ -252,17 +252,20 @@ void NetworkUDPSocketHandler::ReceiveNetworkGameInfo(Packet *p, NetworkGameInfo
 				*dst = c;
 				dst = &c->next;
 			}
-			/* FALL THROUGH */
 		}
+		FALLTHROUGH;
+
 		case 3:
 			info->game_date      = Clamp(p->Recv_uint32(), 0, MAX_DATE);
 			info->start_date     = Clamp(p->Recv_uint32(), 0, MAX_DATE);
-			/* FALL THROUGH */
+			FALLTHROUGH;
+
 		case 2:
 			info->companies_max  = p->Recv_uint8 ();
 			info->companies_on   = p->Recv_uint8 ();
 			info->spectators_max = p->Recv_uint8 ();
-			/* FALL THROUGH */
+			FALLTHROUGH;
+
 		case 1:
 			p->Recv_string(info->server_name,     sizeof(info->server_name));
 			p->Recv_string(info->server_revision, sizeof(info->server_revision));
diff --git a/src/network/network_chat_gui.cpp b/src/network/network_chat_gui.cpp
index f1e54f38d..68e148987 100644
--- a/src/network/network_chat_gui.cpp
+++ b/src/network/network_chat_gui.cpp
@@ -492,10 +492,13 @@ struct NetworkChatWindow : public Window {
 	virtual void OnClick(Point pt, int widget, int click_count)
 	{
 		switch (widget) {
-			/* Send */
-			case WID_NC_SENDBUTTON: SendChat(this->message_editbox.text.buf, this->dtype, this->dest);
-				/* FALL THROUGH */
-			case WID_NC_CLOSE: /* Cancel */ delete this; break;
+			case WID_NC_SENDBUTTON: /* Send */
+				SendChat(this->message_editbox.text.buf, this->dtype, this->dest);
+				FALLTHROUGH;
+
+			case WID_NC_CLOSE: /* Cancel */
+				delete this;
+				break;
 		}
 	}
 
diff --git a/src/network/network_client.cpp b/src/network/network_client.cpp
index edfe4587f..e3bcbb2d8 100644
--- a/src/network/network_client.cpp
+++ b/src/network/network_client.cpp
@@ -965,7 +965,8 @@ NetworkRecvStatus ClientNetworkGameSocketHandler::Receive_SERVER_CHAT(Packet *p)
 			/* For speaking to company or giving money, we need the company-name */
 			case NETWORK_ACTION_GIVE_MONEY:
 				if (!Company::IsValidID(ci_to->client_playas)) return NETWORK_RECV_STATUS_OKAY;
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case NETWORK_ACTION_CHAT_COMPANY: {
 				StringID str = Company::IsValidID(ci_to->client_playas) ? STR_COMPANY_NAME : STR_NETWORK_SPECTATORS;
 				SetDParam(0, ci_to->client_playas);
diff --git a/src/network/network_content_gui.cpp b/src/network/network_content_gui.cpp
index 1227d43db..4b1332c58 100644
--- a/src/network/network_content_gui.cpp
+++ b/src/network/network_content_gui.cpp
@@ -908,7 +908,8 @@ public:
 					}
 					return ES_HANDLED;
 				}
-				/* FALL THROUGH, space is pressed and filter is focused. */
+				/* space is pressed and filter is focused. */
+				FALLTHROUGH;
 
 			default:
 				return ES_NOT_HANDLED;
diff --git a/src/network/network_gui.cpp b/src/network/network_gui.cpp
index 520c4f60a..3e4a4b050 100644
--- a/src/network/network_gui.cpp
+++ b/src/network/network_gui.cpp
@@ -2053,7 +2053,8 @@ struct NetworkJoinStatusWindow : Window {
 					progress = 15; // We don't have the final size yet; the server is still compressing!
 					break;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			default: // Waiting is 15%, so the resting receivement of map is maximum 70%
 				progress = 15 + _network_join_bytes * (100 - 15) / _network_join_bytes_total;
 		}
@@ -2182,7 +2183,7 @@ struct NetworkCompanyPasswordWindow : public Window {
 		switch (widget) {
 			case WID_NCP_OK:
 				this->OnOk();
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case WID_NCP_CANCEL:
 				delete this;
diff --git a/src/network/network_server.cpp b/src/network/network_server.cpp
index 6a33c73d8..bcee40852 100644
--- a/src/network/network_server.cpp
+++ b/src/network/network_server.cpp
@@ -1361,7 +1361,8 @@ void NetworkServerSendChat(NetworkAction action, DestType desttype, int dest, co
 		}
 		default:
 			DEBUG(net, 0, "[server] received unknown chat destination type %d. Doing broadcast instead", desttype);
-			/* FALL THROUGH */
+			FALLTHROUGH;
+
 		case DESTTYPE_BROADCAST:
 			FOR_ALL_CLIENT_SOCKETS(cs) {
 				cs->SendChat(action, from_id, false, msg, data);
@@ -1396,7 +1397,7 @@ NetworkRecvStatus ServerNetworkGameSocketHandler::Receive_CLIENT_CHAT(Packet *p)
 	switch (action) {
 		case NETWORK_ACTION_GIVE_MONEY:
 			if (!Company::IsValidID(ci->client_playas)) break;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 		case NETWORK_ACTION_CHAT:
 		case NETWORK_ACTION_CHAT_CLIENT:
 		case NETWORK_ACTION_CHAT_COMPANY:
diff --git a/src/newgrf.cpp b/src/newgrf.cpp
index 9c7188ec7..24b0238b3 100644
--- a/src/newgrf.cpp
+++ b/src/newgrf.cpp
@@ -2969,7 +2969,7 @@ static ChangeInfoResult CargoChangeInfo(uint cid, int numinfo, int prop, ByteRea
 					case 0x0B: cs->town_effect = TE_FOOD; break;
 					default:
 						grfmsg(1, "CargoChangeInfo: Unknown town growth substitute value %d, setting to none.", substitute_type);
-						/* FALL THROUGH */
+						FALLTHROUGH;
 					case 0xFF: cs->town_effect = TE_NONE; break;
 				}
 				break;
@@ -4094,7 +4094,7 @@ static ChangeInfoResult RailTypeChangeInfo(uint id, int numinfo, int prop, ByteR
 					RailType rt = GetRailTypeByLabel(BSWAP32(label), false);
 					if (rt != INVALID_RAILTYPE) {
 						switch (prop) {
-							case 0x0F: SetBit(rti->powered_railtypes, rt); // Powered implies compatible.
+							case 0x0F: SetBit(rti->powered_railtypes, rt);               FALLTHROUGH; // Powered implies compatible.
 							case 0x0E: SetBit(rti->compatible_railtypes, rt);            break;
 							case 0x18: SetBit(rti->introduction_required_railtypes, rt); break;
 							case 0x19: SetBit(rti->introduces_railtypes, rt);            break;
@@ -4211,7 +4211,7 @@ static ChangeInfoResult RailTypeReserveInfo(uint id, int numinfo, int prop, Byte
 					break;
 				}
 				grfmsg(1, "RailTypeReserveInfo: Ignoring property 1D for rail type %u because no label was set", id + i);
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case 0x0E: // Compatible railtype list
 			case 0x0F: // Powered railtype list
@@ -4350,7 +4350,7 @@ static bool HandleChangeInfoResult(const char *caller, ChangeInfoResult cir, uin
 
 		case CIR_UNKNOWN:
 			grfmsg(0, "%s: Unknown property 0x%02X of feature 0x%02X, disabling", caller, property, feature);
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case CIR_INVALID_ID: {
 			/* No debug message for an invalid ID, as it has already been output */
diff --git a/src/newgrf_gui.cpp b/src/newgrf_gui.cpp
index c3007ac42..c0aa160c2 100644
--- a/src/newgrf_gui.cpp
+++ b/src/newgrf_gui.cpp
@@ -1032,8 +1032,9 @@ struct NewGRFWindow : public Window, NewGRFScanCallback {
 					if (this->editable && this->active_sel != NULL) SetObjectToPlaceWnd(SPR_CURSOR_MOUSE, PAL_NONE, HT_DRAG, this);
 					break;
 				}
-				/* FALL THROUGH, with double click. */
+				/* With double click, continue */
 			}
+			FALLTHROUGH;
 
 			case WID_NS_REMOVE: { // Remove GRF
 				if (this->active_sel == NULL || !this->editable) break;
@@ -1087,8 +1088,9 @@ struct NewGRFWindow : public Window, NewGRFScanCallback {
 					if (this->editable && this->avail_sel != NULL && !HasBit(this->avail_sel->flags, GCF_INVALID)) SetObjectToPlaceWnd(SPR_CURSOR_MOUSE, PAL_NONE, HT_DRAG, this);
 					break;
 				}
-				/* FALL THROUGH, with double click. */
+				/* With double click, continue */
 			}
+			FALLTHROUGH;
 
 			case WID_NS_ADD:
 				if (this->avail_sel == NULL || !this->editable || HasBit(this->avail_sel->flags, GCF_INVALID)) break;
@@ -1225,10 +1227,12 @@ struct NewGRFWindow : public Window, NewGRFScanCallback {
 				}
 
 				this->avails.ForceRebuild();
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case GOID_NEWGRF_LIST_EDITED:
 				this->preset = -1;
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case GOID_NEWGRF_PRESET_LOADED: {
 				/* Update scrollbars */
 				int i = 0;
diff --git a/src/newgrf_industries.cpp b/src/newgrf_industries.cpp
index ef8e9fa9b..e8486e760 100644
--- a/src/newgrf_industries.cpp
+++ b/src/newgrf_industries.cpp
@@ -128,7 +128,7 @@ static uint32 GetCountAndDistanceOfClosestInstance(byte param_setID, byte layout
 
 		case 0xFFFFFFFF: // current grf
 			GrfID = GetIndustrySpec(current->type)->grf_prop.grffile->grfid;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		default: // use the grfid specified in register 100h
 			SetBit(param_setID, 7); // bit 7 means it is not an old type
diff --git a/src/newgrf_industries.h b/src/newgrf_industries.h
index 57e44e8c0..94a502166 100644
--- a/src/newgrf_industries.h
+++ b/src/newgrf_industries.h
@@ -48,9 +48,11 @@ struct IndustriesResolverObject : public ResolverObject {
 			case VSG_SCOPE_PARENT: {
 				TownScopeResolver *tsr = this->GetTown();
 				if (tsr != NULL) return tsr;
-				/* FALL-THROUGH */
 			}
-			default: return ResolverObject::GetScope(scope, relative);
+			FALLTHROUGH;
+
+			default:
+				return ResolverObject::GetScope(scope, relative);
 		}
 	}
 };
diff --git a/src/newgrf_object.cpp b/src/newgrf_object.cpp
index 3f48a819f..058d5e0c0 100644
--- a/src/newgrf_object.cpp
+++ b/src/newgrf_object.cpp
@@ -232,7 +232,7 @@ static uint32 GetCountAndDistanceOfClosestInstance(byte local_id, uint32 grfid,
 
 		case 0xFFFFFFFF: // current grf
 			grf_id = grfid;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		default: // use the grfid specified in register 100h
 			idx = _object_mngr.GetID(local_id, grf_id);
diff --git a/src/newgrf_object.h b/src/newgrf_object.h
index 4a3b770d2..cbd06b6f6 100644
--- a/src/newgrf_object.h
+++ b/src/newgrf_object.h
@@ -128,10 +128,11 @@ struct ObjectResolverObject : public ResolverObject {
 			case VSG_SCOPE_PARENT: {
 				TownScopeResolver *tsr = this->GetTown();
 				if (tsr != NULL) return tsr;
-				/* FALL-THROUGH */
 			}
+			FALLTHROUGH;
 
-			default: return ResolverObject::GetScope(scope, relative);
+			default:
+				return ResolverObject::GetScope(scope, relative);
 		}
 	}
 
diff --git a/src/newgrf_station.h b/src/newgrf_station.h
index ffb827cb3..b9333c105 100644
--- a/src/newgrf_station.h
+++ b/src/newgrf_station.h
@@ -59,8 +59,8 @@ struct StationResolverObject : public ResolverObject {
 			case VSG_SCOPE_PARENT: {
 				TownScopeResolver *tsr = this->GetTown();
 				if (tsr != NULL) return tsr;
-				/* FALL-THROUGH */
 			}
+			FALLTHROUGH;
 
 			default:
 				return ResolverObject::GetScope(scope, relative);
diff --git a/src/order_cmd.cpp b/src/order_cmd.cpp
index 57b29f3f5..db812f6c5 100644
--- a/src/order_cmd.cpp
+++ b/src/order_cmd.cpp
@@ -772,7 +772,8 @@ CommandCost CmdInsertOrder(TileIndex tile, DoCommandFlag flags, uint32 p1, uint3
 				case OSL_PLATFORM_NEAR_END:
 				case OSL_PLATFORM_MIDDLE:
 					if (v->type != VEH_TRAIN) return CMD_ERROR;
-					/* FALL THROUGH */
+					FALLTHROUGH;
+
 				case OSL_PLATFORM_FAR_END:
 					break;
 
@@ -880,7 +881,8 @@ CommandCost CmdInsertOrder(TileIndex tile, DoCommandFlag flags, uint32 p1, uint3
 				case OCV_LOAD_PERCENTAGE:
 				case OCV_RELIABILITY:
 					if (new_order.GetConditionValue() > 100) return CMD_ERROR;
-					/* FALL THROUGH */
+					FALLTHROUGH;
+
 				default:
 					if (occ == OCC_IS_TRUE || occ == OCC_IS_FALSE) return CMD_ERROR;
 					break;
@@ -1466,7 +1468,8 @@ CommandCost CmdModifyOrder(TileIndex tile, DoCommandFlag flags, uint32 p1, uint3
 					case OCV_LOAD_PERCENTAGE:
 					case OCV_RELIABILITY:
 						if (order->GetConditionValue() > 100) order->SetConditionValue(100);
-						/* FALL THROUGH */
+						FALLTHROUGH;
+
 					default:
 						if (occ == OCC_IS_TRUE || occ == OCC_IS_FALSE) order->SetConditionComparator(OCC_EQUALS);
 						break;
diff --git a/src/order_gui.cpp b/src/order_gui.cpp
index 3ca29e087..9045fac6b 100644
--- a/src/order_gui.cpp
+++ b/src/order_gui.cpp
@@ -841,7 +841,7 @@ public:
 			case VIWD_AUTOREPLACE:
 				/* Autoreplace replaced the vehicle */
 				this->vehicle = Vehicle::Get(this->window_number);
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case VIWD_CONSIST_CHANGED:
 				/* Vehicle composition was changed. */
diff --git a/src/pathfinder/yapf/yapf_destrail.hpp b/src/pathfinder/yapf/yapf_destrail.hpp
index 681034a2f..03519b059 100644
--- a/src/pathfinder/yapf/yapf_destrail.hpp
+++ b/src/pathfinder/yapf/yapf_destrail.hpp
@@ -140,7 +140,8 @@ public:
 					 * waypoint. */
 					Yapf().DisableCache(true);
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case OT_GOTO_STATION:
 				m_destTile = CalcClosestStationTile(v->current_order.GetDestination(), v->tile, v->current_order.IsType(OT_GOTO_STATION) ? STATION_RAIL : STATION_WAYPOINT);
 				m_dest_station_id = v->current_order.GetDestination();
diff --git a/src/rail_cmd.cpp b/src/rail_cmd.cpp
index 5582666b1..9f284fc30 100644
--- a/src/rail_cmd.cpp
+++ b/src/rail_cmd.cpp
@@ -554,8 +554,8 @@ CommandCost CmdBuildSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, u
 			if (IsLevelCrossing(tile) && GetCrossingRailBits(tile) == trackbit) {
 				return_cmd_error(STR_ERROR_ALREADY_BUILT);
 			}
-			/* FALL THROUGH */
 		}
+		FALLTHROUGH;
 
 		default: {
 			/* Will there be flat water on the lower halftile? */
@@ -2444,33 +2444,60 @@ static void DrawTile_Track(TileInfo *ti)
 			SpriteID ground = GetCustomRailSprite(rti, ti->tile, RTSG_GROUND);
 
 			switch (GetRailDepotDirection(ti->tile)) {
-				case DIAGDIR_NE: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
-				case DIAGDIR_SW: DrawGroundSprite(ground + RTO_X, PAL_NONE); break;
-				case DIAGDIR_NW: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
-				case DIAGDIR_SE: DrawGroundSprite(ground + RTO_Y, PAL_NONE); break;
-				default: break;
+				case DIAGDIR_NE:
+					if (!IsInvisibilitySet(TO_BUILDINGS)) break;
+					FALLTHROUGH;
+				case DIAGDIR_SW:
+					DrawGroundSprite(ground + RTO_X, PAL_NONE);
+					break;
+				case DIAGDIR_NW:
+					if (!IsInvisibilitySet(TO_BUILDINGS)) break;
+					FALLTHROUGH;
+				case DIAGDIR_SE:
+					DrawGroundSprite(ground + RTO_Y, PAL_NONE);
+					break;
+				default:
+					break;
 			}
 
 			if (_settings_client.gui.show_track_reservation && HasDepotReservation(ti->tile)) {
 				SpriteID overlay = GetCustomRailSprite(rti, ti->tile, RTSG_OVERLAY);
 
 				switch (GetRailDepotDirection(ti->tile)) {
-					case DIAGDIR_NE: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
-					case DIAGDIR_SW: DrawGroundSprite(overlay + RTO_X, PALETTE_CRASH); break;
-					case DIAGDIR_NW: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
-					case DIAGDIR_SE: DrawGroundSprite(overlay + RTO_Y, PALETTE_CRASH); break;
-					default: break;
+					case DIAGDIR_NE:
+						if (!IsInvisibilitySet(TO_BUILDINGS)) break;
+						FALLTHROUGH;
+					case DIAGDIR_SW:
+						DrawGroundSprite(overlay + RTO_X, PALETTE_CRASH);
+						break;
+					case DIAGDIR_NW:
+						if (!IsInvisibilitySet(TO_BUILDINGS)) break;
+						FALLTHROUGH;
+					case DIAGDIR_SE:
+						DrawGroundSprite(overlay + RTO_Y, PALETTE_CRASH);
+						break;
+					default:
+						break;
 				}
 			}
 		} else {
 			/* PBS debugging, draw reserved tracks darker */
 			if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation && HasDepotReservation(ti->tile)) {
 				switch (GetRailDepotDirection(ti->tile)) {
-					case DIAGDIR_NE: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
-					case DIAGDIR_SW: DrawGroundSprite(rti->base_sprites.single_x, PALETTE_CRASH); break;
-					case DIAGDIR_NW: if (!IsInvisibilitySet(TO_BUILDINGS)) break; // else FALL THROUGH
-					case DIAGDIR_SE: DrawGroundSprite(rti->base_sprites.single_y, PALETTE_CRASH); break;
-					default: break;
+					case DIAGDIR_NE:
+						if (!IsInvisibilitySet(TO_BUILDINGS)) break;
+						FALLTHROUGH;
+					case DIAGDIR_SW:
+						DrawGroundSprite(rti->base_sprites.single_x, PALETTE_CRASH);
+						break;
+					case DIAGDIR_NW:
+						if (!IsInvisibilitySet(TO_BUILDINGS)) break;
+						FALLTHROUGH;
+					case DIAGDIR_SE:
+						DrawGroundSprite(rti->base_sprites.single_y, PALETTE_CRASH);
+						break;
+					default:
+						break;
 				}
 			}
 		}
diff --git a/src/saveload/afterload.cpp b/src/saveload/afterload.cpp
index 8b5967175..d5d9bc3a4 100644
--- a/src/saveload/afterload.cpp
+++ b/src/saveload/afterload.cpp
@@ -154,7 +154,7 @@ static void ConvertTownOwner()
 				if (GB(_m[tile].m5, 4, 2) == ROAD_TILE_CROSSING && HasBit(_m[tile].m3, 7)) {
 					_m[tile].m3 = OWNER_TOWN;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case MP_TUNNELBRIDGE:
 				if (_m[tile].m1 & 0x80) SetTileOwner(tile, OWNER_TOWN);
diff --git a/src/saveload/company_sl.cpp b/src/saveload/company_sl.cpp
index 733bc0eaf..d7c313027 100644
--- a/src/saveload/company_sl.cpp
+++ b/src/saveload/company_sl.cpp
@@ -185,7 +185,7 @@ void AfterLoadCompanyStats()
 						}
 					}
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case MP_OBJECT:
 				if (GetWaterClass(tile) == WATER_CLASS_CANAL) {
diff --git a/src/saveload/vehicle_sl.cpp b/src/saveload/vehicle_sl.cpp
index d7c701189..2234659ab 100644
--- a/src/saveload/vehicle_sl.cpp
+++ b/src/saveload/vehicle_sl.cpp
@@ -433,8 +433,8 @@ void AfterLoadVehicles(bool part_of_load)
 				RoadVehicle *rv = RoadVehicle::From(v);
 				rv->roadtype = HasBit(EngInfo(v->First()->engine_type)->misc_flags, EF_ROAD_TRAM) ? ROADTYPE_TRAM : ROADTYPE_ROAD;
 				rv->compatible_roadtypes = RoadTypeToRoadTypes(rv->roadtype);
-				/* FALL THROUGH */
 			}
+			FALLTHROUGH;
 
 			case VEH_TRAIN:
 			case VEH_SHIP:
diff --git a/src/script/api/script_error.cpp b/src/script/api/script_error.cpp
index 24c491995..87d2906c5 100644
--- a/src/script/api/script_error.cpp
+++ b/src/script/api/script_error.cpp
@@ -40,7 +40,8 @@ ScriptError::ScriptErrorMapString ScriptError::error_map_string = ScriptError::S
 
 		case TEXT_TAB_SPECIAL:
 			if (index < 0xE4) break; // Player name
-			/* FALL THROUGH */
+			FALLTHROUGH;
+
 		case TEXT_TAB_TOWN:
 			if (index < 0xC0) break; // Town name
 			/* These strings are 'random' and have no meaning.
diff --git a/src/settings.cpp b/src/settings.cpp
index 9fba3a13f..d81945022 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -178,7 +178,8 @@ static int ParseIntList(const char *p, int *items, int maxitems)
 				/* Do not accept multiple commas between numbers */
 				if (!comma) return -1;
 				comma = false;
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case ' ':
 				p++;
 				break;
diff --git a/src/signal.cpp b/src/signal.cpp
index 8e870b53d..b37e15074 100644
--- a/src/signal.cpp
+++ b/src/signal.cpp
@@ -504,7 +504,8 @@ static SigSegState UpdateSignalsInBuffer(Owner owner)
 					_tbdset.Add(tile, INVALID_DIAGDIR); // start from depot inside
 					break;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case MP_STATION:
 			case MP_ROAD:
 				if ((TrackStatusToTrackBits(GetTileTrackStatus(tile, TRANSPORT_RAIL, 0)) & _enterdir_to_trackbits[dir]) != TRACK_BIT_NONE) {
@@ -513,7 +514,8 @@ static SigSegState UpdateSignalsInBuffer(Owner owner)
 					_tbdset.Add(tile + TileOffsByDiagDir(dir), ReverseDiagDir(dir));
 					break;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			default:
 				/* jump to next tile */
 				tile = tile + TileOffsByDiagDir(dir);
diff --git a/src/signs_gui.cpp b/src/signs_gui.cpp
index 020ee1b6e..15adef089 100644
--- a/src/signs_gui.cpp
+++ b/src/signs_gui.cpp
@@ -514,7 +514,7 @@ struct SignWindow : Window, SignList {
 
 			case WID_QES_OK:
 				if (RenameSign(this->cur_sign, this->name_editbox.text.buf)) break;
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case WID_QES_CANCEL:
 				delete this;
diff --git a/src/smallmap_gui.cpp b/src/smallmap_gui.cpp
index f4bcdece1..0bb2997e5 100644
--- a/src/smallmap_gui.cpp
+++ b/src/smallmap_gui.cpp
@@ -1229,10 +1229,12 @@ void SmallMapWindow::RebuildColourIndexIfNecessary()
 						if (tbl->show_on_map && tbl->type == _smallmap_industry_highlight) {
 							legend_colour = _smallmap_industry_highlight_state ? PC_WHITE : PC_BLACK;
 						}
-						/* FALL THROUGH */
+						FALLTHROUGH;
+
 					case SMT_LINKSTATS:
 						SetDParam(0, tbl->legend);
-						/* FALL_THROUGH */
+						FALLTHROUGH;
+
 					case SMT_OWNER:
 						if (this->map_type != SMT_OWNER || tbl->company != INVALID_COMPANY) {
 							if (this->map_type == SMT_OWNER) SetDParam(0, tbl->company);
@@ -1246,7 +1248,8 @@ void SmallMapWindow::RebuildColourIndexIfNecessary()
 							}
 							break;
 						}
-						/* FALL_THROUGH */
+						FALLTHROUGH;
+
 					default:
 						if (this->map_type == SMT_CONTOUR) SetDParam(0, tbl->height * TILE_HEIGHT_STEP);
 						/* Anything that is not an industry or a company is using normal process */
@@ -1465,7 +1468,6 @@ int SmallMapWindow::GetPositionOnLegend(Point pt)
 			break;
 
 		case WID_SM_ENABLE_ALL:
-			/* FALL THROUGH */
 		case WID_SM_DISABLE_ALL: {
 			LegendAndColour *tbl = NULL;
 			switch (this->map_type) {
diff --git a/src/spritecache.cpp b/src/spritecache.cpp
index 70a8834a9..579791d0d 100644
--- a/src/spritecache.cpp
+++ b/src/spritecache.cpp
@@ -818,7 +818,7 @@ static void *HandleInvalidSpriteRequest(SpriteID sprite, SpriteType requested, S
 	switch (requested) {
 		case ST_NORMAL:
 			if (sprite == SPR_IMG_QUERY) usererror("Uhm, would you be so kind not to load a NewGRF that makes the 'query' sprite a non-normal sprite?");
-			/* FALL THROUGH */
+			FALLTHROUGH;
 		case ST_FONT:
 			return GetRawSprite(SPR_IMG_QUERY, ST_NORMAL, allocator);
 		case ST_RECOLOUR:
diff --git a/src/station_cmd.cpp b/src/station_cmd.cpp
index ea890688e..5fd865a0d 100644
--- a/src/station_cmd.cpp
+++ b/src/station_cmd.cpp
@@ -3091,7 +3091,8 @@ static void TileLoop_Station(TileIndex tile)
 
 		case STATION_DOCK:
 			if (!IsTileFlat(tile)) break; // only handle water part
-			/* FALL THROUGH */
+			FALLTHROUGH;
+
 		case STATION_OILRIG: //(station part)
 		case STATION_BUOY:
 			TileLoop_Water(tile);
diff --git a/src/stdafx.h b/src/stdafx.h
index 4616212f1..43e52ff27 100644
--- a/src/stdafx.h
+++ b/src/stdafx.h
@@ -156,6 +156,17 @@
 	#else
 		#define FINAL
 	#endif
+
+	/* Use fallthrough attribute where supported */
+	#if __GNUC__ >= 7
+		#if __cplusplus > 201402L // C++17
+			#define FALLTHROUGH [[fallthrough]]
+		#else
+			#define FALLTHROUGH __attribute__((fallthrough))
+		#endif
+	#else
+		#define FALLTHROUGH
+	#endif
 #endif /* __GNUC__ */
 
 #if defined(__WATCOMC__)
@@ -164,6 +175,7 @@
 	#define GCC_PACK
 	#define WARN_FORMAT(string, args)
 	#define FINAL
+	#define FALLTHROUGH
 	#include <malloc.h>
 #endif /* __WATCOMC__ */
 
@@ -235,6 +247,13 @@
 	#define WARN_FORMAT(string, args)
 	#define FINAL sealed
 
+	/* fallthrough attribute, VS 2017 */
+	#if (_MSC_VER >= 1910)
+		#define FALLTHROUGH [[fallthrough]]
+	#else
+		#define FALLTHROUGH
+	#endif
+
 	#if defined(WINCE)
 		int CDECL vsnprintf(char *str, size_t size, const char *format, va_list ap);
 	#endif
diff --git a/src/terraform_gui.cpp b/src/terraform_gui.cpp
index 6274de8cd..97749a8dc 100644
--- a/src/terraform_gui.cpp
+++ b/src/terraform_gui.cpp
@@ -80,12 +80,14 @@ static void GenerateRockyArea(TileIndex end, TileIndex start)
 		switch (GetTileType(tile)) {
 			case MP_TREES:
 				if (GetTreeGround(tile) == TREE_GROUND_SHORE) continue;
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case MP_CLEAR:
 				MakeClear(tile, CLEAR_ROCKS, 3);
 				break;
 
-			default: continue;
+			default:
+				continue;
 		}
 		MarkTileDirtyByTile(tile);
 		success = true;
diff --git a/src/timetable_gui.cpp b/src/timetable_gui.cpp
index ffea9a864..664dc8034 100644
--- a/src/timetable_gui.cpp
+++ b/src/timetable_gui.cpp
@@ -197,7 +197,8 @@ struct TimetableWindow : Window {
 				this->deparr_time_width = GetStringBoundingBox(STR_JUST_DATE_TINY).width;
 				this->deparr_abbr_width = max(GetStringBoundingBox(STR_TIMETABLE_ARRIVAL_ABBREVIATION).width, GetStringBoundingBox(STR_TIMETABLE_DEPARTURE_ABBREVIATION).width);
 				size->width = WD_FRAMERECT_LEFT + this->deparr_abbr_width + 10 + this->deparr_time_width + WD_FRAMERECT_RIGHT;
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case WID_VT_ARRIVAL_DEPARTURE_SELECTION:
 			case WID_VT_TIMETABLE_PANEL:
 				resize->height = FONT_HEIGHT_NORMAL;
diff --git a/src/town_cmd.cpp b/src/town_cmd.cpp
index 66092ff34..daaad7e8d 100644
--- a/src/town_cmd.cpp
+++ b/src/town_cmd.cpp
@@ -1244,7 +1244,7 @@ static void GrowTownInTile(TileIndex *tile_ptr, RoadBits cur_rb, DiagDirection t
 
 				case TL_3X3_GRID: // Use 2x2 grid afterwards!
 					GrowTownWithExtraHouse(t1, TileAddByDiagDir(house_tile, target_dir));
-					/* FALL THROUGH */
+					FALLTHROUGH;
 
 				case TL_2X2_GRID:
 					rcmd = GetTownRoadGridElement(t1, tile, target_dir);
@@ -1253,7 +1253,7 @@ static void GrowTownInTile(TileIndex *tile_ptr, RoadBits cur_rb, DiagDirection t
 
 				case TL_BETTER_ROADS: // Use original afterwards!
 					GrowTownWithExtraHouse(t1, TileAddByDiagDir(house_tile, target_dir));
-					/* FALL THROUGH */
+					FALLTHROUGH;
 
 				case TL_ORIGINAL:
 					/* Allow a house at the edge. 60% chance or
@@ -3259,7 +3259,7 @@ Town *ClosestTownFromTile(TileIndex tile, uint threshold)
 
 				return town;
 			}
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case MP_HOUSE:
 			return Town::GetByTile(tile);
diff --git a/src/town_gui.cpp b/src/town_gui.cpp
index 142966b69..696b71afd 100644
--- a/src/town_gui.cpp
+++ b/src/town_gui.cpp
@@ -267,9 +267,10 @@ public:
 					this->sel_index = y;
 					this->SetDirty();
 				}
-				/* FALL THROUGH, when double-clicking. */
+				/* When double-clicking, continue */
 				if (click_count == 1 || y < 0) break;
 			}
+			FALLTHROUGH;
 
 			case WID_TA_EXECUTE:
 				DoCommandP(this->town->xy, this->window_number, this->sel_index, CMD_DO_TOWN_ACTION | CMD_MSG(STR_ERROR_CAN_T_DO_THIS));
diff --git a/src/train_cmd.cpp b/src/train_cmd.cpp
index 608ce2fee..fb1d2b1ee 100644
--- a/src/train_cmd.cpp
+++ b/src/train_cmd.cpp
@@ -2502,6 +2502,7 @@ public:
 				case OT_GOTO_DEPOT:
 					/* Skip service in depot orders when the train doesn't need service. */
 					if ((order->GetDepotOrderType() & ODTFB_SERVICE) && !this->v->NeedsServicing()) break;
+					FALLTHROUGH;
 				case OT_GOTO_STATION:
 				case OT_GOTO_WAYPOINT:
 					this->v->current_order = *order;
@@ -3608,7 +3609,7 @@ static bool TrainApproachingLineEnd(Train *v, bool signal, bool reverse)
 	 * for other directions, it will be 1, 3, 5, ..., 15 */
 	switch (v->direction) {
 		case DIR_N : x = ~x + ~y + 25; break;
-		case DIR_NW: x = y;            // FALL THROUGH
+		case DIR_NW: x = y;            FALLTHROUGH;
 		case DIR_NE: x = ~x + 16;      break;
 		case DIR_E : x = ~x + y + 9;   break;
 		case DIR_SE: x = y;            break;
diff --git a/src/tree_cmd.cpp b/src/tree_cmd.cpp
index c862f0dbc..7240cf86d 100644
--- a/src/tree_cmd.cpp
+++ b/src/tree_cmd.cpp
@@ -375,7 +375,8 @@ CommandCost CmdPlantTree(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 					msg = STR_ERROR_CAN_T_BUILD_ON_WATER;
 					continue;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
+
 			case MP_CLEAR: {
 				if (IsBridgeAbove(tile)) {
 					msg = STR_ERROR_SITE_UNSUITABLE;
@@ -680,7 +681,7 @@ static void TileLoop_Trees(TileIndex tile)
 							SetTreeGrowth(tile, 0);
 							break;
 						}
-						/* FALL THROUGH */
+						FALLTHROUGH;
 
 					case 2: { // add a neighbouring tree
 						/* Don't plant extra trees if that's not allowed. */
diff --git a/src/vehicle.cpp b/src/vehicle.cpp
index 4dbdf24df..dff9febc0 100644
--- a/src/vehicle.cpp
+++ b/src/vehicle.cpp
@@ -1269,7 +1269,7 @@ bool Vehicle::HandleBreakdown()
 			SetWindowDirty(WC_VEHICLE_VIEW, this->index);
 			SetWindowDirty(WC_VEHICLE_DETAILS, this->index);
 
-			/* FALL THROUGH */
+			FALLTHROUGH;
 		case 1:
 			/* Aircraft breakdowns end only when arriving at the airport */
 			if (this->type == VEH_AIRCRAFT) return false;
diff --git a/src/vehicle_gui.cpp b/src/vehicle_gui.cpp
index b9c24ddd0..b50457d21 100644
--- a/src/vehicle_gui.cpp
+++ b/src/vehicle_gui.cpp
@@ -817,8 +817,8 @@ struct RefitWindow : public Window {
 				Vehicle *v = Vehicle::Get(this->window_number);
 				this->selected_vehicle = v->index;
 				this->num_vehicles = UINT8_MAX;
-				/* FALL THROUGH */
 			}
+			FALLTHROUGH;
 
 			case 2: { // The vehicle selection has changed; rebuild the entire list.
 				if (!gui_scope) break;
@@ -843,8 +843,8 @@ struct RefitWindow : public Window {
 					this->information_width = max_width;
 					this->ReInit();
 				}
-				/* FALL THROUGH */
 			}
+			FALLTHROUGH;
 
 			case 1: // A new cargo has been selected.
 				if (!gui_scope) break;
@@ -905,8 +905,8 @@ struct RefitWindow : public Window {
 					if (_ctrl_pressed) this->num_vehicles = UINT8_MAX;
 					break;
 				}
-				/* FALL THROUGH */
 			}
+			FALLTHROUGH;
 
 			default:
 				/* Clear the selection. */
@@ -940,8 +940,8 @@ struct RefitWindow : public Window {
 				this->InvalidateData(1);
 
 				if (click_count == 1) break;
-				/* FALL THROUGH */
 			}
+			FALLTHROUGH;
 
 			case WID_VR_REFIT: // refit button
 				if (this->cargo != NULL) {
@@ -2638,8 +2638,7 @@ public:
 						str = STR_VEHICLE_STATUS_LEAVING;
 						break;
 					}
-					/* FALL THROUGH, if aircraft. Does this even happen? */
-
+					FALLTHROUGH;
 				default:
 					if (v->GetNumManualOrders() == 0) {
 						str = STR_VEHICLE_STATUS_NO_ORDERS_VEL;
diff --git a/src/vehiclelist.cpp b/src/vehiclelist.cpp
index f1f5d0424..bfe4e5ffd 100644
--- a/src/vehiclelist.cpp
+++ b/src/vehiclelist.cpp
@@ -156,7 +156,7 @@ bool GenerateVehicleSortList(VehicleList *list, const VehicleListIdentifier &vli
 				}
 				break;
 			}
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case VL_STANDARD:
 			FOR_ALL_VEHICLES(v) {
diff --git a/src/video/cocoa/event.mm b/src/video/cocoa/event.mm
index c8d10717e..1298961dc 100644
--- a/src/video/cocoa/event.mm
+++ b/src/video/cocoa/event.mm
@@ -610,7 +610,7 @@ static bool QZ_PollEvent()
 			 * the mouse position programmatically, which would trigger OS X to show
 			 * the default arrow cursor if the events are propagated. */
 			if (_cursor.fix_at) break;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		default:
 			[ NSApp sendEvent:event ];
diff --git a/src/video/win32_v.cpp b/src/video/win32_v.cpp
index e536ae8e5..4a9861b64 100644
--- a/src/video/win32_v.cpp
+++ b/src/video/win32_v.cpp
@@ -680,7 +680,7 @@ static LRESULT CALLBACK WndProcGdi(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lP
 
 		case WM_PALETTECHANGED:
 			if ((HWND)wParam == hwnd) return 0;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case WM_QUERYNEWPALETTE: {
 			HDC hDC = GetWindowDC(hwnd);
diff --git a/src/viewport.cpp b/src/viewport.cpp
index a1bb2c81d..df431ff3c 100644
--- a/src/viewport.cpp
+++ b/src/viewport.cpp
@@ -2633,8 +2633,8 @@ static int CalcHeightdiff(HighLightStyle style, uint distance, TileIndex start_t
 			byte style_t = (byte)(TileX(end_tile) > TileX(start_tile));
 			start_tile = TILE_ADD(start_tile, ToTileIndexDiff(heightdiff_area_by_dir[style_t]));
 			end_tile   = TILE_ADD(end_tile, ToTileIndexDiff(heightdiff_area_by_dir[2 + style_t]));
-			/* FALL THROUGH */
 		}
+		FALLTHROUGH;
 
 		case HT_POINT:
 			h0 = TileHeight(start_tile);
@@ -2979,7 +2979,7 @@ void VpSelectTilesWithMethod(int x, int y, ViewportPlaceMethod method)
 
 		case VPM_X_LIMITED: // Drag in X direction (limited size).
 			limit = (_thd.sizelimit - 1) * TILE_SIZE;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case VPM_FIX_X: // drag in Y direction
 			x = sx;
@@ -2988,7 +2988,7 @@ void VpSelectTilesWithMethod(int x, int y, ViewportPlaceMethod method)
 
 		case VPM_Y_LIMITED: // Drag in Y direction (limited size).
 			limit = (_thd.sizelimit - 1) * TILE_SIZE;
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case VPM_FIX_Y: // drag in X direction
 			y = sy;
@@ -3026,7 +3026,7 @@ calc_heightdiff_single_direction:;
 			limit = (_thd.sizelimit - 1) * TILE_SIZE;
 			x = sx + Clamp(x - sx, -limit, limit);
 			y = sy + Clamp(y - sy, -limit, limit);
-			/* FALL THROUGH */
+			FALLTHROUGH;
 
 		case VPM_X_AND_Y: // drag an X by Y area
 			if (_settings_client.gui.measure_tooltip) {
diff --git a/src/water_cmd.cpp b/src/water_cmd.cpp
index 4392eb210..edce4cda5 100644
--- a/src/water_cmd.cpp
+++ b/src/water_cmd.cpp
@@ -437,7 +437,7 @@ CommandCost CmdBuildCanal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32
 						MakeSea(tile);
 						break;
 					}
-					/* FALL THROUGH */
+					FALLTHROUGH;
 
 				default:
 					MakeCanal(tile, _current_company, Random());
@@ -1015,7 +1015,7 @@ FloodingBehaviour GetFloodingBehaviour(TileIndex tile)
 				Slope tileh = GetTileSlope(tile);
 				return (IsSlopeWithOneCornerRaised(tileh) ? FLOOD_ACTIVE : FLOOD_DRYUP);
 			}
-			/* FALL THROUGH */
+			FALLTHROUGH;
 		case MP_STATION:
 		case MP_INDUSTRY:
 		case MP_OBJECT:
@@ -1064,7 +1064,7 @@ void DoFloodTile(TileIndex target)
 					flooded = true;
 					break;
 				}
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case MP_CLEAR:
 				if (DoCommand(target, 0, 0, DC_EXEC, CMD_LANDSCAPE_CLEAR).Succeeded()) {
diff --git a/src/widget.cpp b/src/widget.cpp
index 0f1743b90..4e411ada2 100644
--- a/src/widget.cpp
+++ b/src/widget.cpp
@@ -2287,8 +2287,8 @@ void NWidgetLeaf::SetupSmallestSize(Window *w, bool init_array)
 			Dimension sprite_size = GetSpriteSize(_current_text_dir == TD_RTL ? SPR_IMG_DELETE_RIGHT : SPR_IMG_DELETE_LEFT);
 			size.width = max(size.width, 30 + sprite_size.width);
 			size.height = max(sprite_size.height, GetStringBoundingBox("_").height + WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM);
-			/* FALL THROUGH */
 		}
+		FALLTHROUGH;
 		case WWT_PUSHBTN: {
 			static const Dimension extra = {WD_FRAMERECT_LEFT + WD_FRAMERECT_RIGHT, WD_FRAMERECT_TOP + WD_FRAMERECT_BOTTOM};
 			padding = &extra;
diff --git a/src/window.cpp b/src/window.cpp
index 8378f60f7..6538caffd 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -1277,26 +1277,33 @@ static uint GetWindowZPriority(const Window *w)
 	switch (w->window_class) {
 		case WC_ENDSCREEN:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_HIGHSCORE:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_TOOLTIPS:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_DROPDOWN_MENU:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_MAIN_TOOLBAR:
 		case WC_STATUS_BAR:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_OSK:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_QUERY_STRING:
 		case WC_SEND_NETWORK_MSG:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_ERRMSG:
 		case WC_CONFIRM_POPUP_QUERY:
@@ -1304,6 +1311,7 @@ static uint GetWindowZPriority(const Window *w)
 		case WC_NETWORK_STATUS_WINDOW:
 		case WC_SAVE_PRESET:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_GENERATE_LANDSCAPE:
 		case WC_SAVELOAD:
@@ -1315,15 +1323,19 @@ static uint GetWindowZPriority(const Window *w)
 		case WC_AI_SETTINGS:
 		case WC_TEXTFILE:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_CONSOLE:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_NEWS_WINDOW:
 			++z_priority;
+			FALLTHROUGH;
 
 		default:
 			++z_priority;
+			FALLTHROUGH;
 
 		case WC_MAIN_WINDOW:
 			return z_priority;
@@ -2867,7 +2879,7 @@ static void MouseLoop(MouseClick click, int mousewheel)
 				if (!scrollwheel_scrolling || w == NULL || w->window_class != WC_SMALLMAP) break;
 				/* We try to use the scrollwheel to scroll since we didn't touch any of the buttons.
 				 * Simulate a right button click so we can get started. */
-				/* FALL THROUGH */
+				FALLTHROUGH;
 
 			case MC_RIGHT: DispatchRightClickEvent(w, x - w->left, y - w->top); break;