1 // errorcheck 2 3 // Copyright 2009 The Go Authors. All rights reserved. 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file. 6 7 // Verify overflow is detected when using numeric constants. 8 // Does not compile. 9 10 package main 11 12 import "unsafe" 13 14 type I interface{} 15 16 const ( 17 // assume all types behave similarly to int8/uint8 18 Int8 int8 = 101 19 Minus1 int8 = -1 20 Uint8 uint8 = 102 21 Const = 103 22 23 Float32 float32 = 104.5 24 Float64 float64 = 105.5 25 ConstFloat = 106.5 26 Big float64 = 1e300 27 28 String = "abc" 29 Bool = true 30 ) 31 32 var ( 33 a1 = Int8 * 100 // ERROR "overflow" 34 a2 = Int8 * -1 // OK 35 a3 = Int8 * 1000 // ERROR "overflow" 36 a4 = Int8 * int8(1000) // ERROR "overflow" 37 a5 = int8(Int8 * 1000) // ERROR "overflow" 38 a6 = int8(Int8 * int8(1000)) // ERROR "overflow" 39 a7 = Int8 - 2*Int8 - 2*Int8 // ERROR "overflow" 40 a8 = Int8 * Const / 100 // ERROR "overflow" 41 a9 = Int8 * (Const / 100) // OK 42 43 b1 = Uint8 * Uint8 // ERROR "overflow" 44 b2 = Uint8 * -1 // ERROR "overflow" 45 b3 = Uint8 - Uint8 // OK 46 b4 = Uint8 - Uint8 - Uint8 // ERROR "overflow" 47 b5 = uint8(^0) // ERROR "overflow" 48 b5a = int64(^0) // OK 49 b6 = ^uint8(0) // OK 50 b6a = ^int64(0) // OK 51 b7 = uint8(Minus1) // ERROR "overflow" 52 b8 = uint8(int8(-1)) // ERROR "overflow" 53 b8a = uint8(-1) // ERROR "overflow" 54 b9 byte = (1 << 10) >> 8 // OK 55 b10 byte = (1 << 10) // ERROR "overflow" 56 b11 byte = (byte(1) << 10) >> 8 // ERROR "overflow" 57 b12 byte = 1000 // ERROR "overflow" 58 b13 byte = byte(1000) // ERROR "overflow" 59 b14 byte = byte(100) * byte(100) // ERROR "overflow" 60 b15 byte = byte(100) * 100 // ERROR "overflow" 61 b16 byte = byte(0) * 1000 // ERROR "overflow" 62 b16a byte = 0 * 1000 // OK 63 b17 byte = byte(0) * byte(1000) // ERROR "overflow" 64 b18 byte = Uint8 / 0 // ERROR "division by zero" 65 66 c1 float64 = Big 67 c2 float64 = Big * Big // ERROR "overflow" 68 c3 float64 = float64(Big) * Big // ERROR "overflow" 69 c4 = Big * Big // ERROR "overflow" 70 c5 = Big / 0 // ERROR "division by zero" 71 c6 = 1000 % 1e3 // ERROR "floating-point % operation|expected integer type" 72 ) 73 74 func f(int) 75 76 func main() { 77 f(Int8) // ERROR "convert|wrong type|cannot" 78 f(Minus1) // ERROR "convert|wrong type|cannot" 79 f(Uint8) // ERROR "convert|wrong type|cannot" 80 f(Const) // OK 81 f(Float32) // ERROR "convert|wrong type|cannot" 82 f(Float64) // ERROR "convert|wrong type|cannot" 83 f(ConstFloat) // ERROR "truncate" 84 f(ConstFloat - 0.5) // OK 85 f(Big) // ERROR "convert|wrong type|cannot" 86 f(String) // ERROR "convert|wrong type|cannot|incompatible" 87 f(Bool) // ERROR "convert|wrong type|cannot|incompatible" 88 } 89 90 const ptr = nil // ERROR "const.*nil" 91 const _ = string([]byte(nil)) // ERROR "is not a? ?constant" 92 const _ = uintptr(unsafe.Pointer((*int)(nil))) // ERROR "is not a? ?constant" 93 const _ = unsafe.Pointer((*int)(nil)) // ERROR "cannot be nil|invalid constant type" 94 const _ = (*int)(nil) // ERROR "cannot be nil|invalid constant type" 95
