gcc-7.1.1-1.fc27.x86_64
/home/jkratoch/redhat/fedora/libipt/master/processor-trace-1.6.1/libipt/src/pt_block_decoder.c: In function ‘pt_blk_proceed_no_event_cached’:
/home/jkratoch/redhat/fedora/libipt/master/processor-trace-1.6.1/libipt/src/pt_block_decoder.c:2282:6: error: this statement may fall through [-Werror=implicit-fallthrough=]
   if (bce.isize) {
      ^
/home/jkratoch/redhat/fedora/libipt/master/processor-trace-1.6.1/libipt/src/pt_block_decoder.c:2328:2: note: here
  case ptbq_decode: {
  ^~~~

diff --git a/libipt/src/pt_block_decoder.c b/libipt/src/pt_block_decoder.c
index 21783a6..91d5bb3 100644
--- a/libipt/src/pt_block_decoder.c
+++ b/libipt/src/pt_block_decoder.c
@@ -2095,6 +2095,9 @@ static int pt_blk_proceed_no_event_cached(struct pt_block_decoder *decoder,
 		}
 
 		/* Fall through to ptbq_decode. */
+#if __GNUC__ >= 7
+		__attribute__ ((fallthrough));
+#endif
 
 	case ptbq_decode: {
 		struct pt_insn_ext iext;