* dwarf2dbg.c: Include safe-ctype.h.

    * dwarf2dbg.c: Include safe-ctype.h.
        (DWARF2_LINE_OPCODE_BASE): Bump to 13.
        (current): Initialize.
        (dwarf2_emit_insn): Clear DWARF2_FLAG_BASIC_BLOCK,
        DWARF2_FLAG_PROLOGUE_END, DWARF2_FLAG_EPILOGUE_BEGIN.
        (dwarf2_directive_file): Cope with invalid filename.
        (dwarf2_directive_loc): Add handling for basic_block, prologue_end,
        epilogue_begin, is_stmt, isa.
        (emit_inc_line_addr): Move line_delta == 0, addr_delta == 0 special
        case down lower.
        (process_entries): Handle isa, DWARF2_FLAG_PROLOGUE_END,
        and DWARF2_FLAG_EPILOGUE_BEGIN.
        (out_debug_line): Emit sizes for DW_LNS_set_prologue_end,
        DW_LNS_set_epilogue_begin, DW_LNS_set_isa.
        * dwarf2dbg.h (DWARF2_FLAG_IS_STMT): Rename from DWARF2_FLAG_BEGIN_STMT.        (DWARF2_FLAG_BASIC_BLOCK): Rename from DWARF2_FLAG_BEGIN_BLOCK.
        (DWARF2_FLAG_PROLOGUE_END, DWARF2_FLAG_EPILOGUE_BEGIN): New.
        (struct dwarf2_line_info): Add isa member.
        * doc/as.texinfo (LNS directives): New node.