// Copyright 2013 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. // +build ignore // This file contains tests for the dead code checker. package testdata type T int var x interface{} var c chan int func external() int // ok func _() int { } func _() int { print(1) } func _() int { print(1) return 2 println() // ERROR "unreachable code" } func _() int { L: print(1) goto L println() // ERROR "unreachable code" } func _() int { print(1) panic(2) println() // ERROR "unreachable code" } // but only builtin panic func _() int { var panic = func(int) {} print(1) panic(2) println() // ok } func _() int { { print(1) return 2 println() // ERROR "unreachable code" } println() // ok } func _() int { { print(1) return 2 } println() // ERROR "unreachable code" } func _() int { L: { print(1) goto L println() // ERROR "unreachable code" } println() // ok } func _() int { L: { print(1) goto L } println() // ERROR "unreachable code" } func _() int { print(1) { panic(2) } } func _() int { print(1) { panic(2) println() // ERROR "unreachable code" } } func _() int { print(1) { panic(2) } println() // ERROR "unreachable code" } func _() int { print(1) return 2 { // ERROR "unreachable code" } } func _() int { L: print(1) goto L { // ERROR "unreachable code" } } func _() int { print(1) panic(2) { // ERROR "unreachable code" } } func _() int { { print(1) return 2 { // ERROR "unreachable code" } } } func _() int { L: { print(1) goto L { // ERROR "unreachable code" } } } func _() int { print(1) { panic(2) { // ERROR "unreachable code" } } } func _() int { { print(1) return 2 } { // ERROR "unreachable code" } } func _() int { L: { print(1) goto L } { // ERROR "unreachable code" } } func _() int { print(1) { panic(2) } { // ERROR "unreachable code" } } func _() int { print(1) if x == nil { panic(2) } else { panic(3) } println() // ERROR "unreachable code" } func _() int { L: print(1) if x == nil { panic(2) } else { goto L } println() // ERROR "unreachable code" } func _() int { L: print(1) if x == nil { panic(2) } else if x == 1 { return 0 } else if x != 2 { panic(3) } else { goto L } println() // ERROR "unreachable code" } // if-else chain missing final else is not okay, even if the // conditions cover every possible case. func _() int { print(1) if x == nil { panic(2) } else if x != nil { panic(3) } println() // ok } func _() int { print(1) if x == nil { panic(2) } println() // ok } func _() int { L: print(1) if x == nil { panic(2) } else if x == 1 { return 0 } else if x != 1 { panic(3) } println() // ok } func _() int { print(1) for { } println() // ERROR "unreachable code" } func _() int { for { for { break } } println() // ERROR "unreachable code" } func _() int { for { for { break println() // ERROR "unreachable code" } } } func _() int { for { for { continue println() // ERROR "unreachable code" } } } func _() int { for { L: for { break L } } println() // ERROR "unreachable code" } func _() int { print(1) for { break } println() // ok } func _() int { for { for { } break // ERROR "unreachable code" } println() // ok } func _() int { L: for { for { break L } } println() // ok } func _() int { print(1) for x == nil { } println() // ok } func _() int { for x == nil { for { break } } println() // ok } func _() int { for x == nil { L: for { break L } } println() // ok } func _() int { print(1) for true { } println() // ok } func _() int { for true { for { break } } println() // ok } func _() int { for true { L: for { break L } } println() // ok } func _() int { print(1) select {} println() // ERROR "unreachable code" } func _() int { print(1) select { case <-c: print(2) panic("abc") println() // ERROR "unreachable code" } } func _() int { print(1) select { case <-c: print(2) panic("abc") } println() // ERROR "unreachable code" } func _() int { print(1) select { case <-c: print(2) for { } println() // ERROR "unreachable code" } } func _() int { print(1) select { case <-c: print(2) for { } } println() // ERROR "unreachable code" } func _() int { L: print(1) select { case <-c: print(2) panic("abc") println() // ERROR "unreachable code" case c <- 1: print(2) goto L println() // ERROR "unreachable code" } } func _() int { L: print(1) select { case <-c: print(2) panic("abc") case c <- 1: print(2) goto L } println() // ERROR "unreachable code" } func _() int { print(1) select { case <-c: print(2) panic("abc") println() // ERROR "unreachable code" default: select {} println() // ERROR "unreachable code" } } func _() int { print(1) select { case <-c: print(2) panic("abc") default: select {} } println() // ERROR "unreachable code" } func _() int { print(1) select { case <-c: print(2) } println() // ok } func _() int { L: print(1) select { case <-c: print(2) panic("abc") goto L // ERROR "unreachable code" case c <- 1: print(2) } println() // ok } func _() int { print(1) select { case <-c: print(2) panic("abc") default: print(2) } println() // ok } func _() int { print(1) select { default: break } println() // ok } func _() int { print(1) select { case <-c: print(2) panic("abc") break // ERROR "unreachable code" } println() // ok } func _() int { print(1) L: select { case <-c: print(2) for { break L } } println() // ok } func _() int { print(1) L: select { case <-c: print(2) panic("abc") case c <- 1: print(2) break L } println() // ok } func _() int { print(1) select { case <-c: print(1) panic("abc") default: select {} break // ERROR "unreachable code" } println() // ok } func _() int { print(1) switch x { case 1: print(2) panic(3) println() // ERROR "unreachable code" default: return 4 println() // ERROR "unreachable code" } } func _() int { print(1) switch x { case 1: print(2) panic(3) default: return 4 } println() // ERROR "unreachable code" } func _() int { print(1) switch x { default: return 4 println() // ERROR "unreachable code" case 1: print(2) panic(3) println() // ERROR "unreachable code" } } func _() int { print(1) switch x { default: return 4 case 1: print(2) panic(3) } println() // ERROR "unreachable code" } func _() int { print(1) switch x { case 1: print(2) fallthrough default: return 4 println() // ERROR "unreachable code" } } func _() int { print(1) switch x { case 1: print(2) fallthrough default: return 4 } println() // ERROR "unreachable code" } func _() int { print(1) switch { } println() // ok } func _() int { print(1) switch x { case 1: print(2) panic(3) case 2: return 4 } println() // ok } func _() int { print(1) switch x { case 2: return 4 case 1: print(2) panic(3) } println() // ok } func _() int { print(1) switch x { case 1: print(2) fallthrough case 2: return 4 } println() // ok } func _() int { print(1) switch x { case 1: print(2) panic(3) } println() // ok } func _() int { print(1) L: switch x { case 1: print(2) panic(3) break L // ERROR "unreachable code" default: return 4 } println() // ok } func _() int { print(1) switch x { default: return 4 break // ERROR "unreachable code" case 1: print(2) panic(3) } println() // ok } func _() int { print(1) L: switch x { case 1: print(2) for { break L } default: return 4 } println() // ok } func _() int { print(1) switch x.(type) { case int: print(2) panic(3) println() // ERROR "unreachable code" default: return 4 println() // ERROR "unreachable code" } } func _() int { print(1) switch x.(type) { case int: print(2) panic(3) default: return 4 } println() // ERROR "unreachable code" } func _() int { print(1) switch x.(type) { default: return 4 println() // ERROR "unreachable code" case int: print(2) panic(3) println() // ERROR "unreachable code" } } func _() int { print(1) switch x.(type) { default: return 4 case int: print(2) panic(3) } println() // ERROR "unreachable code" } func _() int { print(1) switch x.(type) { case int: print(2) fallthrough default: return 4 println() // ERROR "unreachable code" } } func _() int { print(1) switch x.(type) { case int: print(2) fallthrough default: return 4 } println() // ERROR "unreachable code" } func _() int { print(1) switch { } println() // ok } func _() int { print(1) switch x.(type) { case int: print(2) panic(3) case float64: return 4 } println() // ok } func _() int { print(1) switch x.(type) { case float64: return 4 case int: print(2) panic(3) } println() // ok } func _() int { print(1) switch x.(type) { case int: print(2) fallthrough case float64: return 4 } println() // ok } func _() int { print(1) switch x.(type) { case int: print(2) panic(3) } println() // ok } func _() int { print(1) L: switch x.(type) { case int: print(2) panic(3) break L // ERROR "unreachable code" default: return 4 } println() // ok } func _() int { print(1) switch x.(type) { default: return 4 break // ERROR "unreachable code" case int: print(2) panic(3) } println() // ok } func _() int { print(1) L: switch x.(type) { case int: print(2) for { break L } default: return 4 } println() // ok } // again, but without the leading print(1). // testing that everything works when the terminating statement is first. func _() int { println() // ok } func _() int { return 2 println() // ERROR "unreachable code" } func _() int { L: goto L println() // ERROR "unreachable code" } func _() int { panic(2) println() // ERROR "unreachable code" } // but only builtin panic func _() int { var panic = func(int) {} panic(2) println() // ok } func _() int { { return 2 println() // ERROR "unreachable code" } } func _() int { { return 2 } println() // ERROR "unreachable code" } func _() int { L: { goto L println() // ERROR "unreachable code" } } func _() int { L: { goto L } println() // ERROR "unreachable code" } func _() int { { panic(2) println() // ERROR "unreachable code" } } func _() int { { panic(2) } println() // ERROR "unreachable code" } func _() int { return 2 { // ERROR "unreachable code" } println() // ok } func _() int { L: goto L { // ERROR "unreachable code" } println() // ok } func _() int { panic(2) { // ERROR "unreachable code" } println() // ok } func _() int { { return 2 { // ERROR "unreachable code" } } println() // ok } func _() int { L: { goto L { // ERROR "unreachable code" } } println() // ok } func _() int { { panic(2) { // ERROR "unreachable code" } } println() // ok } func _() int { { return 2 } { // ERROR "unreachable code" } println() // ok } func _() int { L: { goto L } { // ERROR "unreachable code" } println() // ok } func _() int { { panic(2) } { // ERROR "unreachable code" } println() // ok } // again, with func literals var _ = func() int { } var _ = func() int { print(1) } var _ = func() int { print(1) return 2 println() // ERROR "unreachable code" } var _ = func() int { L: print(1) goto L println() // ERROR "unreachable code" } var _ = func() int { print(1) panic(2) println() // ERROR "unreachable code" } // but only builtin panic var _ = func() int { var panic = func(int) {} print(1) panic(2) println() // ok } var _ = func() int { { print(1) return 2 println() // ERROR "unreachable code" } println() // ok } var _ = func() int { { print(1) return 2 } println() // ERROR "unreachable code" } var _ = func() int { L: { print(1) goto L println() // ERROR "unreachable code" } println() // ok } var _ = func() int { L: { print(1) goto L } println() // ERROR "unreachable code" } var _ = func() int { print(1) { panic(2) } } var _ = func() int { print(1) { panic(2) println() // ERROR "unreachable code" } } var _ = func() int { print(1) { panic(2) } println() // ERROR "unreachable code" } var _ = func() int { print(1) return 2 { // ERROR "unreachable code" } } var _ = func() int { L: print(1) goto L { // ERROR "unreachable code" } } var _ = func() int { print(1) panic(2) { // ERROR "unreachable code" } } var _ = func() int { { print(1) return 2 { // ERROR "unreachable code" } } } var _ = func() int { L: { print(1) goto L { // ERROR "unreachable code" } } } var _ = func() int { print(1) { panic(2) { // ERROR "unreachable code" } } } var _ = func() int { { print(1) return 2 } { // ERROR "unreachable code" } } var _ = func() int { L: { print(1) goto L } { // ERROR "unreachable code" } } var _ = func() int { print(1) { panic(2) } { // ERROR "unreachable code" } } var _ = func() int { print(1) if x == nil { panic(2) } else { panic(3) } println() // ERROR "unreachable code" } var _ = func() int { L: print(1) if x == nil { panic(2) } else { goto L } println() // ERROR "unreachable code" } var _ = func() int { L: print(1) if x == nil { panic(2) } else if x == 1 { return 0 } else if x != 2 { panic(3) } else { goto L } println() // ERROR "unreachable code" } // if-else chain missing final else is not okay, even if the // conditions cover every possible case. var _ = func() int { print(1) if x == nil { panic(2) } else if x != nil { panic(3) } println() // ok } var _ = func() int { print(1) if x == nil { panic(2) } println() // ok } var _ = func() int { L: print(1) if x == nil { panic(2) } else if x == 1 { return 0 } else if x != 1 { panic(3) } println() // ok } var _ = func() int { print(1) for { } println() // ERROR "unreachable code" } var _ = func() int { for { for { break } } println() // ERROR "unreachable code" } var _ = func() int { for { for { break println() // ERROR "unreachable code" } } } var _ = func() int { for { for { continue println() // ERROR "unreachable code" } } } var _ = func() int { for { L: for { break L } } println() // ERROR "unreachable code" } var _ = func() int { print(1) for { break } println() // ok } var _ = func() int { for { for { } break // ERROR "unreachable code" } println() // ok } var _ = func() int { L: for { for { break L } } println() // ok } var _ = func() int { print(1) for x == nil { } println() // ok } var _ = func() int { for x == nil { for { break } } println() // ok } var _ = func() int { for x == nil { L: for { break L } } println() // ok } var _ = func() int { print(1) for true { } println() // ok } var _ = func() int { for true { for { break } } println() // ok } var _ = func() int { for true { L: for { break L } } println() // ok } var _ = func() int { print(1) select {} println() // ERROR "unreachable code" } var _ = func() int { print(1) select { case <-c: print(2) panic("abc") println() // ERROR "unreachable code" } } var _ = func() int { print(1) select { case <-c: print(2) panic("abc") } println() // ERROR "unreachable code" } var _ = func() int { print(1) select { case <-c: print(2) for { } println() // ERROR "unreachable code" } } var _ = func() int { print(1) select { case <-c: print(2) for { } } println() // ERROR "unreachable code" } var _ = func() int { L: print(1) select { case <-c: print(2) panic("abc") println() // ERROR "unreachable code" case c <- 1: print(2) goto L println() // ERROR "unreachable code" } } var _ = func() int { L: print(1) select { case <-c: print(2) panic("abc") case c <- 1: print(2) goto L } println() // ERROR "unreachable code" } var _ = func() int { print(1) select { case <-c: print(2) panic("abc") println() // ERROR "unreachable code" default: select {} println() // ERROR "unreachable code" } } var _ = func() int { print(1) select { case <-c: print(2) panic("abc") default: select {} } println() // ERROR "unreachable code" } var _ = func() int { print(1) select { case <-c: print(2) } println() // ok } var _ = func() int { L: print(1) select { case <-c: print(2) panic("abc") goto L // ERROR "unreachable code" case c <- 1: print(2) } println() // ok } var _ = func() int { print(1) select { case <-c: print(2) panic("abc") default: print(2) } println() // ok } var _ = func() int { print(1) select { default: break } println() // ok } var _ = func() int { print(1) select { case <-c: print(2) panic("abc") break // ERROR "unreachable code" } println() // ok } var _ = func() int { print(1) L: select { case <-c: print(2) for { break L } } println() // ok } var _ = func() int { print(1) L: select { case <-c: print(2) panic("abc") case c <- 1: print(2) break L } println() // ok } var _ = func() int { print(1) select { case <-c: print(1) panic("abc") default: select {} break // ERROR "unreachable code" } println() // ok } var _ = func() int { print(1) switch x { case 1: print(2) panic(3) println() // ERROR "unreachable code" default: return 4 println() // ERROR "unreachable code" } } var _ = func() int { print(1) switch x { case 1: print(2) panic(3) default: return 4 } println() // ERROR "unreachable code" } var _ = func() int { print(1) switch x { default: return 4 println() // ERROR "unreachable code" case 1: print(2) panic(3) println() // ERROR "unreachable code" } } var _ = func() int { print(1) switch x { default: return 4 case 1: print(2) panic(3) } println() // ERROR "unreachable code" } var _ = func() int { print(1) switch x { case 1: print(2) fallthrough default: return 4 println() // ERROR "unreachable code" } } var _ = func() int { print(1) switch x { case 1: print(2) fallthrough default: return 4 } println() // ERROR "unreachable code" } var _ = func() int { print(1) switch { } println() // ok } var _ = func() int { print(1) switch x { case 1: print(2) panic(3) case 2: return 4 } println() // ok } var _ = func() int { print(1) switch x { case 2: return 4 case 1: print(2) panic(3) } println() // ok } var _ = func() int { print(1) switch x { case 1: print(2) fallthrough case 2: return 4 } println() // ok } var _ = func() int { print(1) switch x { case 1: print(2) panic(3) } println() // ok } var _ = func() int { print(1) L: switch x { case 1: print(2) panic(3) break L // ERROR "unreachable code" default: return 4 } println() // ok } var _ = func() int { print(1) switch x { default: return 4 break // ERROR "unreachable code" case 1: print(2) panic(3) } println() // ok } var _ = func() int { print(1) L: switch x { case 1: print(2) for { break L } default: return 4 } println() // ok } var _ = func() int { print(1) switch x.(type) { case int: print(2) panic(3) println() // ERROR "unreachable code" default: return 4 println() // ERROR "unreachable code" } } var _ = func() int { print(1) switch x.(type) { case int: print(2) panic(3) default: return 4 } println() // ERROR "unreachable code" } var _ = func() int { print(1) switch x.(type) { default: return 4 println() // ERROR "unreachable code" case int: print(2) panic(3) println() // ERROR "unreachable code" } } var _ = func() int { print(1) switch x.(type) { default: return 4 case int: print(2) panic(3) } println() // ERROR "unreachable code" } var _ = func() int { print(1) switch x.(type) { case int: print(2) fallthrough default: return 4 println() // ERROR "unreachable code" } } var _ = func() int { print(1) switch x.(type) { case int: print(2) fallthrough default: return 4 } println() // ERROR "unreachable code" } var _ = func() int { print(1) switch { } println() // ok } var _ = func() int { print(1) switch x.(type) { case int: print(2) panic(3) case float64: return 4 } println() // ok } var _ = func() int { print(1) switch x.(type) { case float64: return 4 case int: print(2) panic(3) } println() // ok } var _ = func() int { print(1) switch x.(type) { case int: print(2) fallthrough case float64: return 4 } println() // ok } var _ = func() int { print(1) switch x.(type) { case int: print(2) panic(3) } println() // ok } var _ = func() int { print(1) L: switch x.(type) { case int: print(2) panic(3) break L // ERROR "unreachable code" default: return 4 } println() // ok } var _ = func() int { print(1) switch x.(type) { default: return 4 break // ERROR "unreachable code" case int: print(2) panic(3) } println() // ok } var _ = func() int { print(1) L: switch x.(type) { case int: print(2) for { break L } default: return 4 } println() // ok } // again, but without the leading print(1). // testing that everything works when the terminating statement is first. var _ = func() int { println() // ok } var _ = func() int { return 2 println() // ERROR "unreachable code" } var _ = func() int { L: goto L println() // ERROR "unreachable code" } var _ = func() int { panic(2) println() // ERROR "unreachable code" } // but only builtin panic var _ = func() int { var panic = func(int) {} panic(2) println() // ok } var _ = func() int { { return 2 println() // ERROR "unreachable code" } } var _ = func() int { { return 2 } println() // ERROR "unreachable code" } var _ = func() int { L: { goto L println() // ERROR "unreachable code" } } var _ = func() int { L: { goto L } println() // ERROR "unreachable code" } var _ = func() int { { panic(2) println() // ERROR "unreachable code" } } var _ = func() int { { panic(2) } println() // ERROR "unreachable code" } var _ = func() int { return 2 { // ERROR "unreachable code" } println() // ok } var _ = func() int { L: goto L { // ERROR "unreachable code" } println() // ok } var _ = func() int { panic(2) { // ERROR "unreachable code" } println() // ok } var _ = func() int { { return 2 { // ERROR "unreachable code" } } println() // ok } var _ = func() int { L: { goto L { // ERROR "unreachable code" } } println() // ok } var _ = func() int { { panic(2) { // ERROR "unreachable code" } } println() // ok } var _ = func() int { { return 2 } { // ERROR "unreachable code" } println() // ok } var _ = func() int { L: { goto L } { // ERROR "unreachable code" } println() // ok } var _ = func() int { { panic(2) } { // ERROR "unreachable code" } println() // ok } var _ = func() { // goto without label used to panic goto }