func (p *Package) writeDefsFunc(fgo2 io.Writer, n *Name, callsMalloc *bool) {
	name := n.Go
	gtype := n.FuncType.Go
	void := gtype.Results == nil || len(gtype.Results.List) == 0
	if n.AddError {
		// Add "error" to return type list.
		// Type list is known to be 0 or 1 element - it's a C function.
		err := &ast.Field{Type: ast.NewIdent("error")}
		l := gtype.Results.List
		if len(l) == 0 {
			l = []*ast.Field{err}
		} else {