go/test/fixedbugs/issue39459.go
Keith Randall 3b2f67a597 cmd/compile: remove check that Zero's arg has the correct base type
It doesn't have to. The type in the aux field is authoritative.
There are cases involving casting from interface{} where pointers
have a placeholder pointer type (because the type is not known when
the IData op is generated).

The check was introduced in CL 13447.

Fixes #39459

Change-Id: Id77a57577806a271aeebd20bea5d92d08ee7aa6b
Reviewed-on: https://go-review.googlesource.com/c/go/+/239817
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2020-06-25 15:59:48 +00:00

23 lines
583 B
Go

// compile
// 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 p
type T struct { // big enough to be an unSSAable type
a, b, c, d, e, f int
}
func f(x interface{}, p *int) {
_ = *p // trigger nil check here, removing it from below
switch x := x.(type) {
case *T:
// Zero twice, so one of them will be removed by the deadstore pass
*x = T{}
*p = 0 // store op to prevent Zero ops from being optimized by the earlier opt pass rewrite rules
*x = T{}
}
}