cmd/compile: generic function instantiated with wrong type

[korzhao]

What version of Go are you using (go version)?

go tip 1.18

$ go version

Does this issue reproduce with the latest release?

Yes

What operating system and processor architecture are you using (go env)?

go env Output

$ go env

What did you do?

package main

import (
	"fmt"
	"reflect"
)

type A[T any] struct {
	B[int]
}
type B[T any] struct {
}
func (b B[T]) Bat() {
	t := new(T)
	fmt.Println(reflect.TypeOf(t).String())
}

type Foo struct {
	A[string]
}
func main() {
	Foo{}.A.Bat()
	Foo{}.A.B.Bat()
}

What did you expect to see?

*int
*int

What did you see instead?

*string
*int

[cuonglm]

Unified IR works right:

$ GOEXPERIMENT=unified go run p.go
*int
*int

[gopherbot]

Change https://golang.org/cl/348549 mentions this issue: cmd/compile: fix wrong instantinated type for embedded receiver