f.NamePos = make(map[*Name]token.Pos)

	// In ast1, find the import "C" line and get any extra C preamble.
	sawC := false
	for _, decl := range ast1.Decls {
		switch decl := decl.(type) {
		case *ast.GenDecl:
			for _, spec := range decl.Specs {
				s, ok := spec.(*ast.ImportSpec)
				if !ok || s.Path.Value != `"C"` {
					continue
				}
				sawC = true
				if s.Name != nil {

		ast.Inspect(file, func(n ast.Node) bool {
			switch n := n.(type) {
			case *ast.File:
				if isDeprecated(n.Doc) {
					mark(n.Name)
				}
				return true
			case *ast.GenDecl:
				if isDeprecated(n.Doc) {
					for _, spec := range n.Specs {
						switch spec := spec.(type) {
						case *ast.ValueSpec:
							for _, id := range spec.Names {
								mark(id)
							}