fix fallthrough warnings

src/MurmurHash3.cpp

@@ -120,9 +120,9 @@ void MurmurHash3_x86_32(const void* key, int len, uint32_t seed, void* out) {
 
   switch (len & 3) {
   case 3:
-    k1 ^= tail[2] << 16;
+    k1 ^= tail[2] << 16; [[fallthrough]];
   case 2:
-    k1 ^= tail[1] << 8;
+    k1 ^= tail[1] << 8; [[fallthrough]];
   case 1:
     k1 ^= tail[0];
     k1 *= c1;
@@ -217,48 +217,48 @@ void MurmurHash3_x86_128(const void* key, const int len, uint32_t seed, void* ou
 
   switch (len & 15) {
   case 15:
-    k4 ^= tail[14] << 16;
+    k4 ^= tail[14] << 16; [[fallthrough]];
   case 14:
-    k4 ^= tail[13] << 8;
+    k4 ^= tail[13] << 8; [[fallthrough]];
   case 13:
     k4 ^= tail[12] << 0;
     k4 *= c4;
     k4 = ROTL32(k4, 18);
     k4 *= c1;
-    h4 ^= k4;
+    h4 ^= k4; [[fallthrough]];
 
   case 12:
-    k3 ^= tail[11] << 24;
+    k3 ^= tail[11] << 24; [[fallthrough]];
   case 11:
-    k3 ^= tail[10] << 16;
+    k3 ^= tail[10] << 16; [[fallthrough]];
   case 10:
-    k3 ^= tail[9] << 8;
+    k3 ^= tail[9] << 8; [[fallthrough]];
   case 9:
     k3 ^= tail[8] << 0;
     k3 *= c3;
     k3 = ROTL32(k3, 17);
     k3 *= c4;
-    h3 ^= k3;
+    h3 ^= k3; [[fallthrough]];
 
   case 8:
-    k2 ^= tail[7] << 24;
+    k2 ^= tail[7] << 24; [[fallthrough]];
   case 7:
-    k2 ^= tail[6] << 16;
+    k2 ^= tail[6] << 16; [[fallthrough]];
   case 6:
-    k2 ^= tail[5] << 8;
+    k2 ^= tail[5] << 8; [[fallthrough]];
   case 5:
     k2 ^= tail[4] << 0;
     k2 *= c2;
     k2 = ROTL32(k2, 16);
     k2 *= c3;
-    h2 ^= k2;
+    h2 ^= k2; [[fallthrough]];
 
   case 4:
-    k1 ^= tail[3] << 24;
+    k1 ^= tail[3] << 24; [[fallthrough]];
   case 3:
-    k1 ^= tail[2] << 16;
+    k1 ^= tail[2] << 16; [[fallthrough]];
   case 2:
-    k1 ^= tail[1] << 8;
+    k1 ^= tail[1] << 8; [[fallthrough]];
   case 1:
     k1 ^= tail[0] << 0;
     k1 *= c1;
@@ -350,38 +350,38 @@ void MurmurHash3_x64_128(const void* key, const int len, const uint32_t seed, vo
 
   switch (len & 15) {
   case 15:
-    k2 ^= ((uint64_t)tail[14]) << 48;
+    k2 ^= ((uint64_t)tail[14]) << 48; [[fallthrough]];
   case 14:
-    k2 ^= ((uint64_t)tail[13]) << 40;
+    k2 ^= ((uint64_t)tail[13]) << 40; [[fallthrough]];
   case 13:
-    k2 ^= ((uint64_t)tail[12]) << 32;
+    k2 ^= ((uint64_t)tail[12]) << 32; [[fallthrough]];
   case 12:
-    k2 ^= ((uint64_t)tail[11]) << 24;
+    k2 ^= ((uint64_t)tail[11]) << 24; [[fallthrough]];
   case 11:
-    k2 ^= ((uint64_t)tail[10]) << 16;
+    k2 ^= ((uint64_t)tail[10]) << 16; [[fallthrough]];
   case 10:
-    k2 ^= ((uint64_t)tail[9]) << 8;
+    k2 ^= ((uint64_t)tail[9]) << 8; [[fallthrough]];
   case 9:
     k2 ^= ((uint64_t)tail[8]) << 0;
     k2 *= c2;
     k2 = ROTL64(k2, 33);
     k2 *= c1;
-    h2 ^= k2;
+    h2 ^= k2; [[fallthrough]];
 
   case 8:
-    k1 ^= ((uint64_t)tail[7]) << 56;
+    k1 ^= ((uint64_t)tail[7]) << 56; [[fallthrough]];
   case 7:
-    k1 ^= ((uint64_t)tail[6]) << 48;
+    k1 ^= ((uint64_t)tail[6]) << 48; [[fallthrough]];
   case 6:
-    k1 ^= ((uint64_t)tail[5]) << 40;
+    k1 ^= ((uint64_t)tail[5]) << 40; [[fallthrough]];
   case 5:
-    k1 ^= ((uint64_t)tail[4]) << 32;
+    k1 ^= ((uint64_t)tail[4]) << 32; [[fallthrough]];
   case 4:
-    k1 ^= ((uint64_t)tail[3]) << 24;
+    k1 ^= ((uint64_t)tail[3]) << 24; [[fallthrough]];
   case 3:
-    k1 ^= ((uint64_t)tail[2]) << 16;
+    k1 ^= ((uint64_t)tail[2]) << 16; [[fallthrough]];
   case 2:
-    k1 ^= ((uint64_t)tail[1]) << 8;
+    k1 ^= ((uint64_t)tail[1]) << 8; [[fallthrough]];
   case 1:
     k1 ^= ((uint64_t)tail[0]) << 0;
     k1 *= c1;