diff --git a/src/cmd/compile/internal/typecheck/subr.go b/src/cmd/compile/internal/typecheck/subr.go index 34f20879f1..5323872eaf 100644 --- a/src/cmd/compile/internal/typecheck/subr.go +++ b/src/cmd/compile/internal/typecheck/subr.go @@ -1312,6 +1312,7 @@ func (ts *Tsubster) tstruct(t *types.Type, force bool) *types.Type { // the type param, not the instantiated type). newfields[i] = types.NewField(f.Pos, f.Sym, t2) newfields[i].Embedded = f.Embedded + newfields[i].Note = f.Note if f.IsDDD() { newfields[i].SetIsDDD(true) } diff --git a/test/typeparam/issue48317.go b/test/typeparam/issue48317.go new file mode 100644 index 0000000000..c8f088dc7a --- /dev/null +++ b/test/typeparam/issue48317.go @@ -0,0 +1,38 @@ +// 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 ( + "encoding/json" +) + +type A[T any] struct { + F1 string `json:"t1"` + F2 T `json:"t2"` + B B `json:"t3"` +} + +type B struct { + F4 int `json:"t4"` +} + +func a[T any]() { + data := `{"t1":"1","t2":2,"t3":{"t4":4}}` + a1 := A[T]{} + if err := json.Unmarshal([]byte(data), &a1); err != nil { + panic(err) + } + if bytes, err := json.Marshal(&a1); err != nil { + panic(err) + } else if string(bytes) != data { + panic(string(bytes)) + } +} + +func main() { + a[int]() +}