go/test/typeparam/issue49295.go
Keith Randall d4e0e8e4a4 cmd/compile: make pointers to arrays their own shape
Pointers to arrays can be used to cast from a slice. We need
the shape of such type params to be different so we can compile
those casts correctly.

This is kind of a big hammer to fix #49295. It would be nice to
only do this when we know there's a []T->*[N]T conversion.

Fixes #49295

Change-Id: Ibda33057fab2dd28162537aab0f1244211d68e3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/361135
Trust: Keith Randall <khr@golang.org>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
2021-11-03 17:56:16 +00:00

31 lines
556 B
Go

// run -gcflags=-G=3
// Copyright 2021 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
import "io"
type Reader struct {
buf []byte
}
type Token *[16]byte
func Read[T interface{ ~*[16]byte }](r *Reader) (t T, err error) {
if n := len(t); len(r.buf) >= n {
t = T(r.buf[:n])
r.buf = r.buf[n:]
return
}
err = io.EOF
return
}
func main() {
r := &Reader{buf: []byte("0123456789abcdef")}
token, err := Read[Token](r)
_, _ = token, err
}