* dwarf2dbg.c (dwarf2_gen_line_info): Mirror the section symbol

    * dwarf2dbg.c (dwarf2_gen_line_info): Mirror the section symbol
        creation logic from obj_elf_create_section.
        * config/obj-elf.c (elf_pseudo_tab): Add pushsection/popsection.
        (section_stack): New.
        (special_sections): Make const.
        (obj_elf_section): Gut and rewrite parsing.
        (obj_elf_change_section): New function broken out of obj_elf_section.
        (obj_elf_parse_section_letters): Likewise.
        (obj_elf_section_word): Likewise.
        (obj_elf_section_type): Likewise.
        (obj_elf_previous): Treat as a toggle.
        (obj_elf_popsection): New.
        * config/tc-ppc.c (ppc_section_word): Take str+len not ptr_str.
        (ppc_section_type): Likewise.
        * config/tc-ppc.h: Likewise.
        * expr.h (struct expressionS): Don't make X_op a bitfield.
        * config/tc-alpha.c: Update for symbol handling changes.
        (md_apply_fix) [case GPREL]: Use now_seg instead of absolute_section.
        (load_expression, emit_ir_load, emit_loadstore, emit_jsrjmp): Likewise.