T := pkg.Scope().Lookup("T").Type().(*Named)
	if n := T.TypeParams().Len(); n != 1 {
		t.Fatalf("expected 1 type parameter; found %d", n)
	}

	// instantiation should succeed (no endless recursion)
	// even with a nil *Checker
	res, err := Instantiate(nil, T, []Type{Typ[Int]}, false)
	if err != nil {
		t.Fatal(err)
	}

	// instantiated type should point to itself

	T := pkg.Scope().Lookup("T").Type().(*Named)
	if n := T.TypeParams().Len(); n != 1 {
		t.Fatalf("expected 1 type parameter; found %d", n)
	}

	// instantiation should succeed (no endless recursion)
	// even with a nil *Checker
	res, err := Instantiate(nil, T, []Type{Typ[Int]}, false)
	if err != nil {
		t.Fatal(err)
	}

	// instantiated type should point to itself

	// name.  This is used by types to implement the inside-out
	// C++ declaration syntax.
	inner []AST

	// The printing field is a list of items we are currently
	// printing.  This avoids endless recursion if a substitution
	// reference creates a cycle in the graph.
	printing []AST
}

// writeByte adds a byte to the string being printed.
func (ps *printState) writeByte(b byte) {
	ps.last = b

- [`KT-65005`](https://youtrack.jetbrains.com/issue/KT-65005) K2: Investigate testCommonSuperTypeContravariant performance
- [`KT-65996`](https://youtrack.jetbrains.com/issue/KT-65996) Compiler enters endless loop
- [`KT-66341`](https://youtrack.jetbrains.com/issue/KT-66341) K2: Don't build IdSignatures in FIR2IR with IR f/o builder