/usr/share/go-1.8/test/sliceopt.go is in golang-1.8-src 1.8.3-2ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 | // errorcheck -0 -d=append,slice,ssa/prove/debug=1
// Copyright 2015 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.
// Check optimization results for append and slicing.
package main
func a1(x []int, y int) []int {
x = append(x, y) // ERROR "append: len-only update \(in local slice\)$"
return x
}
func a2(x []int, y int) []int {
return append(x, y)
}
func a3(x *[]int, y int) {
*x = append(*x, y) // ERROR "append: len-only update$"
}
// s1_if_false_then_anything
func s1_if_false_then_anything(x **[]int, xs **string, i, j int) {
z := (**x)[0:i]
z = z[i : i+1]
println(z) // if we get here, then we have proven that i==i+1 (this cannot happen, but the program is still being analyzed...)
zs := (**xs)[0:i] // since i=i+1 is proven, i+1 is "in bounds", ha-ha
zs = zs[i : i+1] // ERROR "Proved boolean IsSliceInBounds$"
println(zs)
}
func s1(x **[]int, xs **string, i, j int) {
var z []int
z = (**x)[2:]
z = (**x)[2:len(**x)] // ERROR "Proved boolean IsSliceInBounds$"
z = (**x)[2:cap(**x)] // ERROR "Proved IsSliceInBounds$"
z = (**x)[i:i] // -ERROR "Proved IsSliceInBounds"
z = (**x)[1:i:i] // ERROR "Proved boolean IsSliceInBounds$"
z = (**x)[i:j:0]
z = (**x)[i:0:j] // ERROR "Disproved IsSliceInBounds$"
z = (**x)[0:i:j] // ERROR "Proved boolean IsSliceInBounds$"
z = (**x)[0:] // ERROR "slice: omit slice operation$"
z = (**x)[2:8] // ERROR "Proved slicemask not needed$"
println(z)
z = (**x)[2:2]
z = (**x)[0:i]
z = (**x)[2:i:8] // ERROR "Disproved IsSliceInBounds$" "Proved IsSliceInBounds$"
z = (**x)[i:2:i] // ERROR "Proved IsSliceInBounds$" "Proved boolean IsSliceInBounds$"
z = z[0:i] // ERROR "Proved boolean IsSliceInBounds"
z = z[0:i : i+1]
z = z[i : i+1] // ERROR "Proved boolean IsSliceInBounds$"
println(z)
var zs string
zs = (**xs)[2:]
zs = (**xs)[2:len(**xs)] // ERROR "Proved IsSliceInBounds$" "Proved boolean IsSliceInBounds$"
zs = (**xs)[i:i] // -ERROR "Proved boolean IsSliceInBounds"
zs = (**xs)[0:] // ERROR "slice: omit slice operation$"
zs = (**xs)[2:8]
zs = (**xs)[2:2] // ERROR "Proved boolean IsSliceInBounds$"
zs = (**xs)[0:i] // ERROR "Proved boolean IsSliceInBounds$"
zs = zs[0:i] // See s1_if_false_then_anything above to explain the counterfactual bounds check result below
zs = zs[i : i+1] // ERROR "Proved boolean IsSliceInBounds$"
println(zs)
}
|