From b1f259b1b42f055863a67492e7815ec752eae56b Mon Sep 17 00:00:00 2001 From: Cuong Manh Le Date: Fri, 25 Apr 2025 19:13:52 +0700 Subject: [PATCH] cmd/compile: fix ICE with recursive alias type parameter CL 585399 fixed an initialization loop during IR contruction that involving alias type, by avoiding publishing alias declarations until the RHS type expression has been constructed. There's an assertion to ensure that the alias's type must be the same during the initialization. However, that assertion is too strict, since we may construct different instances of the same type, if the type is an instantination of generic type. To fix this, we could use types.IdenticalStrict to ensure that these types matching exactly. Updates #66873. Updates #73309. Change-Id: I2559bed37e21615854333fb1057d7349406e6a1b Reviewed-on: https://go-review.googlesource.com/c/go/+/668175 Reviewed-by: David Chase Reviewed-by: Keith Randall Auto-Submit: Cuong Manh Le LUCI-TryBot-Result: Go LUCI Reviewed-by: Keith Randall --- src/cmd/compile/internal/noder/reader.go | 2 +- src/cmd/compile/internal/types2/stdlib_test.go | 1 + src/go/types/stdlib_test.go | 1 + test/fixedbugs/issue73309.go | 18 ++++++++++++++++++ 4 files changed, 21 insertions(+), 1 deletion(-) create mode 100644 test/fixedbugs/issue73309.go diff --git a/src/cmd/compile/internal/noder/reader.go b/src/cmd/compile/internal/noder/reader.go index 05052651c6..95054a4f8b 100644 --- a/src/cmd/compile/internal/noder/reader.go +++ b/src/cmd/compile/internal/noder/reader.go @@ -762,7 +762,7 @@ func (pr *pkgReader) objIdxMayFail(idx index, implicits, explicits []*types.Type if hack { if sym.Def != nil { name = sym.Def.(*ir.Name) - assert(name.Type() == typ) + assert(types.IdenticalStrict(name.Type(), typ)) return name, nil } sym.Def = name diff --git a/src/cmd/compile/internal/types2/stdlib_test.go b/src/cmd/compile/internal/types2/stdlib_test.go index 6966bb94b0..4de698baaf 100644 --- a/src/cmd/compile/internal/types2/stdlib_test.go +++ b/src/cmd/compile/internal/types2/stdlib_test.go @@ -332,6 +332,7 @@ func TestStdFixed(t *testing.T) { "issue49814.go", // go/types does not have constraints on array size "issue56103.go", // anonymous interface cycles; will be a type checker error in 1.22 "issue52697.go", // types2 does not have constraints on stack size + "issue73309.go", // this test requires GODEBUG=gotypesalias=1 // These tests requires runtime/cgo.Incomplete, which is only available on some platforms. // However, types2 does not know about build constraints. diff --git a/src/go/types/stdlib_test.go b/src/go/types/stdlib_test.go index ec76f8ee17..633d7be84d 100644 --- a/src/go/types/stdlib_test.go +++ b/src/go/types/stdlib_test.go @@ -334,6 +334,7 @@ func TestStdFixed(t *testing.T) { "issue49814.go", // go/types does not have constraints on array size "issue56103.go", // anonymous interface cycles; will be a type checker error in 1.22 "issue52697.go", // go/types does not have constraints on stack size + "issue73309.go", // this test requires GODEBUG=gotypesalias=1 // These tests requires runtime/cgo.Incomplete, which is only available on some platforms. // However, go/types does not know about build constraints. diff --git a/test/fixedbugs/issue73309.go b/test/fixedbugs/issue73309.go new file mode 100644 index 0000000000..5e96e6513b --- /dev/null +++ b/test/fixedbugs/issue73309.go @@ -0,0 +1,18 @@ +// compile + +// Copyright 2025 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 + +type B[T any] struct { + a A[T] +} + +type A[T any] = func(B[T]) bool + +func main() { + var s A[int] + println(s) +} -- 2.50.0