testing: t.Helper() confused by generics

[earthboundkid]

If you make a typed alias to a function, t.Helper() gets confused about where the error comes from.

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

1.18

Does this issue reproduce with the latest release?

Yes.

What did you do?

https://go.dev/play/p/GOOGiEsdm_O

func Helper[T any](t *testing.T) {
	t.Helper()
	t.Error("x")
}

var typedHelper = Helper[int]

func TestHelper(t *testing.T) {
	Helper[int](t)
	typedHelper(t)
}

What did you expect to see?

    prog.go:13: x
    prog.go:14: x

What did you see instead?

    prog.go:13: x
    prog.go:10: x  ← this is the line where typedHelper is defined

By contrast, this works correctly:

func Helper(t *testing.T) {
	t.Helper()
	t.Error("x")
}

var aliased = Helper

func TestHelper(t *testing.T) {
	Helper(t)
	aliased(t)
}

[heschi]

cc @randall77: ping: this is a release blocker that hasn't been updated in a while.

[gopherbot]

Change https://go.dev/cl/408876 mentions this issue: cmd/compile: mark closures made for generic function expressions as wrappers