// compile -d=ssa/check/on // 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. package main func f() uint32 { s := "food" x := uint32(s[0]) + uint32(s[1])<<8 + uint32(s[2])<<16 + uint32(s[3])<<24 // x is a constant, but that's not known until lowering. // shifting it by 8 moves the high byte up into the high 32 bits of // a 64-bit word. That word is not properly sign-extended by the faulty // rule, which causes the compiler to fail. return x << 8 }