| // run |
| |
| // Copyright 2020 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. |
| |
| // Issue #43480: ICE on large uint64 constants in switch cases. |
| |
| package main |
| |
| func isPow10(x uint64) bool { |
| switch x { |
| case 1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9, |
| 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19: |
| return true |
| } |
| return false |
| } |
| |
| func main() { |
| var x uint64 = 1 |
| |
| for { |
| if !isPow10(x) || isPow10(x-1) || isPow10(x+1) { |
| panic(x) |
| } |
| next := x * 10 |
| if next/10 != x { |
| break // overflow |
| } |
| x = next |
| } |
| } |