cmd/gc: liveness: don't add fallthough edge after panic

update #7205

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/50730044

diff --git a/src/cmd/gc/plive.c b/src/cmd/gc/plive.c
index 5c03eaad6ee3bc73bed58774e1dfcaddca9a6226..4e3eadcd74d9bc21f4138c3bda00662dbb270a71 100644 (file)
--- a/src/cmd/gc/plive.c
+++ b/src/cmd/gc/plive.c
@@ -538,6 +538,7 @@ newcfg(Prog *firstp)
                        switch(bb->last->as) {
                        case AJMP:
                        case ARET:
+                       case AUNDEF:
                                break;
                        default:
                                addedge(bb, bb->last->link->opt);