* expression.cc (eval): Replace dummy argument with NULL.

    * expression.cc (eval): Replace dummy argument with NULL.
        (eval_maybe_dot): Check for a NULL result section pointer.
        (Symbol_expression::value): Likewise.
        (Dot_expression::value): Likewise.
        (BINARY_EXPRESSION): Likewise.
        (Max_expression::value): Likewise.
        (Min_expression::value): Likewise.
        (Absolute_expression::value): Likewise.
        (Addr_expression::value_from_output_section): Likewise.
        (Loaddddr_expression::value_from_output_section): Likewise.
        (Segment_start_expression::value): Likewise.
        * script-sections.cc
        (Sections_elememt_dot_assignment::finalize_symbols): Replace dummy
        argument with NULL.
        (Sections_elememt_dot_assignment::set_section_addresses):
        Likewise.
        (Output_data_expression::do_write_to_buffer): Likewise.
        (Output_section_definition::finalize_symbols): Likewise.
        (Output_section_definition::set_section_addresses): Likewise.