refactor: add [[fallthrough]] annotation (#1886)

gtk/makemeta-ui.cc

@@ -161,8 +161,7 @@ static void onProgressDialogResponse(GtkDialog* d, int response, gpointer data)
 
     case GTK_RESPONSE_ACCEPT:
         addTorrent(ui);
-
-        /* fall-through */
+        [[fallthrough]];
 
     case GTK_RESPONSE_CLOSE:
         gtk_widget_destroy(ui->builder->result ? GTK_WIDGET(d) : ui->dialog);

libtransmission/bandwidth.cc

@@ -247,10 +247,12 @@ void tr_bandwidthAllocate(tr_bandwidth* b, tr_direction dir, unsigned int period
         switch (io->priority)
         {
         case TR_PRI_HIGH:
-            tr_ptrArrayAppend(&high, io); /* fall through */
+            tr_ptrArrayAppend(&high, io);
+            [[fallthrough]];
 
         case TR_PRI_NORMAL:
-            tr_ptrArrayAppend(&normal, io); /* fall through */
+            tr_ptrArrayAppend(&normal, io);
+            [[fallthrough]];
 
         default:
             tr_ptrArrayAppend(&low, io);

libtransmission/tr-lpd.cc

@@ -647,7 +647,7 @@ static int tr_lpdAnnounceMore(time_t const now, int const interval)
                 announcePrio = 2;
                 break;
 
-            default: /* fall through */
+            default:
                 break;
             }
 

libtransmission/tr-macros.h

@@ -121,12 +121,6 @@
 #define TR_GNUC_MALLOC
 #endif
 
-#if __has_attribute(__fallthrough__) || TR_GNUC_CHECK_VERSION(7, 0)
-#define TR_GNUC_FALLTHROUGH __attribute__((__fallthrough__))
-#else
-#define TR_GNUC_FALLTHROUGH
-#endif
-
 /***
 ****
 ***/

libtransmission/trevent.cc

@@ -120,8 +120,8 @@ static int piperead(tr_pipe_end_t s, void* buf, int len)
         case WSAECONNRESET:
             /* EOF on the pipe! (win32 socket based implementation) */
             ret = 0;
+            [[fallthrough]];
 
-        /* fall through */
         default:
             errno = werror;
             break;

qt/Session.cc

@@ -1042,7 +1042,8 @@ void Session::addTorrent(AddData const& add_me, tr_variant* args, bool trash_ori
         dictAdd(args, TR_KEY_filename, add_me.url.toString());
         break;
 
-    case AddData::FILENAME: /* fall-through */
+    case AddData::FILENAME:
+        [[fallthrough]];
     case AddData::METAINFO:
         dictAdd(args, TR_KEY_metainfo, add_me.toBase64());
         break;

utils/remote.cc

@@ -2112,9 +2112,7 @@ static int processResponse(char const* rpcurl, void const* response, size_t len)
                         {
                             tr_snprintf(id, sizeof(id), "%" PRId64, i);
                         }
-
-                        /* fall-through to default: to give success or failure msg */
-                        TR_GNUC_FALLTHROUGH;
+                        [[fallthrough]];
                     }
 
                 default: