From 5e6d144567d31ec778ed5d4fb5d4c99f36973f16 Mon Sep 17 00:00:00 2001
From: Desour <ds.desour@proton.me>
Date: Mon, 12 Jun 2023 22:23:32 +0200
Subject: [PATCH] Enable -Wimplicit-fallthrough and use [[fallthrough]]
 attribute

---
 src/CMakeLists.txt              |  2 +-
 src/client/hud.cpp              |  1 +
 src/rollback_interface.cpp      |  2 ++
 src/script/common/c_content.cpp |  1 +
 src/util/numeric.cpp            | 12 ++++++------
 5 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 91eae9792..3f14e8ec0 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -761,7 +761,7 @@ if(MSVC)
 else()
 	# GCC or compatible compilers such as Clang
 	set(WARNING_FLAGS "-Wall -Wextra")
-	set(WARNING_FLAGS "${WARNING_FLAGS} -Wno-unused-parameter -Wno-implicit-fallthrough")
+	set(WARNING_FLAGS "${WARNING_FLAGS} -Wno-unused-parameter")
 	if(WARN_ALL)
 		set(RELEASE_WARNING_FLAGS "${WARNING_FLAGS}")
 	else()
diff --git a/src/client/hud.cpp b/src/client/hud.cpp
index b18bd5382..9ad5ef5e9 100644
--- a/src/client/hud.cpp
+++ b/src/client/hud.cpp
@@ -440,6 +440,7 @@ void Hud::drawLuaElements(const v3s16 &camera_offset)
 			case HUD_ELEM_IMAGE_WAYPOINT: {
 				if (!calculateScreenPos(camera_offset, e, &pos))
 					break;
+				[[fallthrough]];
 			}
 			case HUD_ELEM_IMAGE: {
 				video::ITexture *texture = tsrc->getTexture(e->text);
diff --git a/src/rollback_interface.cpp b/src/rollback_interface.cpp
index 6f19f441d..a5a63076f 100644
--- a/src/rollback_interface.cpp
+++ b/src/rollback_interface.cpp
@@ -65,6 +65,7 @@ std::string RollbackAction::toString() const
 		os << ", " << itos(n_new.param2);
 		os << ", " << serializeJsonString(n_new.meta);
 		os << ')';
+		break;
 	case TYPE_MODIFY_INVENTORY_STACK:
 		os << "modify_inventory_stack (";
 		os << serializeJsonString(inventory_location);
@@ -73,6 +74,7 @@ std::string RollbackAction::toString() const
 		os << ", " << (inventory_add ? "add" : "remove");
 		os << ", " << serializeJsonString(inventory_stack.getItemString());
 		os << ')';
+		break;
 	default:
 		return "<unknown action>";
 	}
diff --git a/src/script/common/c_content.cpp b/src/script/common/c_content.cpp
index 9a9132c09..299975100 100644
--- a/src/script/common/c_content.cpp
+++ b/src/script/common/c_content.cpp
@@ -478,6 +478,7 @@ TileDef read_tiledef(lua_State *L, int index, u8 drawtype, bool special)
 			// "break" is omitted here intentionaly, as PLANTLIKE
 			// FIRELIKE drawtype both should default to having
 			// backface_culling to false.
+			[[fallthrough]];
 		case NDT_MESH:
 		case NDT_LIQUID:
 			default_culling = false;
diff --git a/src/util/numeric.cpp b/src/util/numeric.cpp
index 3bcac5335..423049a37 100644
--- a/src/util/numeric.cpp
+++ b/src/util/numeric.cpp
@@ -90,12 +90,12 @@ u64 murmur_hash_64_ua(const void *key, int len, unsigned int seed)
 
 	const unsigned char *data2 = (const unsigned char *)data;
 	switch (len & 7) {
-		case 7: h ^= (u64)data2[6] << 48;
-		case 6: h ^= (u64)data2[5] << 40;
-		case 5: h ^= (u64)data2[4] << 32;
-		case 4: h ^= (u64)data2[3] << 24;
-		case 3: h ^= (u64)data2[2] << 16;
-		case 2: h ^= (u64)data2[1] << 8;
+		case 7: h ^= (u64)data2[6] << 48; [[fallthrough]];
+		case 6: h ^= (u64)data2[5] << 40; [[fallthrough]];
+		case 5: h ^= (u64)data2[4] << 32; [[fallthrough]];
+		case 4: h ^= (u64)data2[3] << 24; [[fallthrough]];
+		case 3: h ^= (u64)data2[2] << 16; [[fallthrough]];
+		case 2: h ^= (u64)data2[1] << 8;  [[fallthrough]];
 		case 1: h ^= (u64)data2[0];
 				h *= m;
 	}