diff options
| -rw-r--r-- | src/cmd/gc/swt.c | 4 | ||||
| -rw-r--r-- | test/switch.go | 9 | ||||
| -rw-r--r-- | test/switch4.go | 36 |
3 files changed, 40 insertions, 9 deletions
diff --git a/src/cmd/gc/swt.c b/src/cmd/gc/swt.c index a497b8622..5fba73140 100644 --- a/src/cmd/gc/swt.c +++ b/src/cmd/gc/swt.c @@ -322,6 +322,10 @@ casebody(Node *sw, Node *typeswvar) setlineno(last); yyerror("cannot fallthrough in type switch"); } + if(l->next == nil) { + setlineno(last); + yyerror("cannot fallthrough final case in switch"); + } last->op = OFALL; } else stat = list(stat, br); diff --git a/test/switch.go b/test/switch.go index bcbde68e4..5e1d85bb6 100644 --- a/test/switch.go +++ b/test/switch.go @@ -392,15 +392,6 @@ func main() { } assert(count == 2, "fail") - // fallthrough in final case. - count = 0 - switch i5 { - case 5: - count++ - fallthrough - } - assert(count == 1, "fail") - i := 0 switch x := 5; { case i < x: diff --git a/test/switch4.go b/test/switch4.go new file mode 100644 index 000000000..f38efe68c --- /dev/null +++ b/test/switch4.go @@ -0,0 +1,36 @@ +// errorcheck + +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Verify that erroneous switch statements are detected by the compiler. +// Does not compile. + +package main + +type I interface { + M() +} + +func bad() { + + i5 := 5 + switch i5 { + case 5: + fallthrough // ERROR "cannot fallthrough final case in switch" + } +} + +func good() { + var i interface{} + var s string + + switch i { + case s: + } + + switch s { + case i: + } +} |