// run // Copyright 2026 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. // Dead-store elimination must use the AuxInt byte count of OpMove, // not the size of its Aux type. The "inline runtime.memmove" rewrite // emits Move {uint8} [N]; if DSE treats that as a 1-byte write, a // trailing 1-byte store appears to fully shadow it and the move is // incorrectly deleted. package main import "fmt" //go:noinline func f() [8]byte { str := "ABCDEFGH" dst := make([]byte, len(str)) copy(dst, str) dst[0] = 99 return [8]byte(dst) } func main() { got := f() want := [8]byte{99, 'B', 'C', 'D', 'E', 'F', 'G', 'H'} if got != want { panic(fmt.Sprintf("got %v, want %v", got, want)) } }