go/test/typeparam/issue46461.go

// errorcheck -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 p

type T[U interface{ M() T[U] }] int // ERROR "invalid recursive type T"

type X int

func (X) M() T[X] { return 0 }
cmd/compile/internal/types2: disallow type cycles through type parameter lists If we reach a generic type that is part of a cycle and we are in a type parameter list, we have a cycle through a type parameter list, which is invalid. Fixes #49439. Change-Id: Ia6cf97e1748ca0c0e61c02841202050091365b0b Reviewed-on: https://go-review.googlesource.com/c/go/+/361922 Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com> 2021-11-08 17:09:11 -07:00			`// errorcheck -G=3`
test: add compiler regress tests for #46461 gri@ reports that types2 now correctly handles when type parameters recursively refer back to the parameterized type, so we might as well add tests to exercise that. Unified IR also correctly handles importing and exporting these types, but -G=3 currently does not. Updates #46461. Change-Id: I272102aa08c40c980b9aeeca9f834291dfbbcc3e Reviewed-on: https://go-review.googlesource.com/c/go/+/348738 Trust: Matthew Dempsky <mdempsky@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org> 2021-09-09 12:17:39 -06:00
			`// 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 p`

cmd/compile/internal/types2: disallow type cycles through type parameter lists If we reach a generic type that is part of a cycle and we are in a type parameter list, we have a cycle through a type parameter list, which is invalid. Fixes #49439. Change-Id: Ia6cf97e1748ca0c0e61c02841202050091365b0b Reviewed-on: https://go-review.googlesource.com/c/go/+/361922 Trust: Robert Griesemer <gri@golang.org> Reviewed-by: Robert Findley <rfindley@google.com> 2021-11-08 17:09:11 -07:00			`type T[U interface{ M() T[U] }] int // ERROR "invalid recursive type T"`
test: add compiler regress tests for #46461 gri@ reports that types2 now correctly handles when type parameters recursively refer back to the parameterized type, so we might as well add tests to exercise that. Unified IR also correctly handles importing and exporting these types, but -G=3 currently does not. Updates #46461. Change-Id: I272102aa08c40c980b9aeeca9f834291dfbbcc3e Reviewed-on: https://go-review.googlesource.com/c/go/+/348738 Trust: Matthew Dempsky <mdempsky@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Robert Griesemer <gri@golang.org> 2021-09-09 12:17:39 -06:00
			`type X int`

			`func (X) M() T[X] { return 0 }`