I happened to run readelf on an ELF file created by Guile. readelf
complained about invalid values for DW_FORM_strp. At first I assumed
this was just a Guile bug, but eu-readelf did the right thing, so I
looked a bit deeper.
I came across some old Mach-O code to bias some offsets by section
addresses. Guile, unlike many ELF writers, sets the address for the
various DWARF-related sections, causing this unusual code to be run.
This code came from an old commit:
2005-09-30 H.J. Lu <hongjiu.lu@intel.com>
* dwarf.c (fetch_indirect_string): Adjust for section address.
(process_debug_info): Likewise.
(display_debug_loc): Likewise.
(display_debug_ranges): Likewise.
* objdump.c (mach_o_dwarf_sections): New.
(generic_dwarf_sections): Likewise.
(check_mach_o_dwarf): Likewise.
(dump_dwarf): Call check_mach_o_dwarf.
However it was partially reverted here:
https://sourceware.org/ml/binutils/2008-11/msg00134.html
This patch just completes the reversion.
Built and regtested on x86-64 Fedora 18. I also ran the resulting
readelf against the Guile-created object with success.
I have no way of testing this on Mach-O, so your feedback is
solicited.
2013-12-19 Tom Tromey <tromey@redhat.com>
* dwarf.c (fetch_indirect_string): Don't bias by section address.
(fetch_indexed_string): Likewise.
(process_debug_info): Likewise.
(display_debug_loc): Likewise.
(display_debug_ranges): Likewise.
* dwarf.c (cu_tu_indexes_read, shndx_pool, shndx_pool_size)
(shndx_pool_used): Move to top of file.
(struct cu_tu_set): New type.
(cu_count, tu_count, cu_sets, tu_sets): New file scope variables.
(fetch_indexed_string): Add "this_set" parameter. Update all callers.
(find_cu_tu_set_v2): New function.
(read_and_display_attr_value): Add "this_set" parameter.
(read_and_display_attr): Likewise.
(process_debug_info): Track base offsets for DWARF package files.
(load_debug_info): Call load_cu_tu_indexes.
(get_DW_SECT_short_name): New function.
(process_cu_tu_index): Add support for version 2 DWARF package files.
* dwarf.c (display_loc_list): Update offset for each line
printed.
(print_addr_index): New function.
(display_loc_list_dwo): Update offset for each line printed.
Fix problems displaying loclists in .dwo files. Add support
for type 4 entries.
(display_debug_loc): Remove custom header for .dwo files.
(display_debug_addr): Adjust formatting.
DW_FORM_GNU_ref_alt and DW_FORM_GNU_strp_alt.
(display_debug_macro): Handle DW_MACRO_GNU_define_indirect_alt,
DW_MACRO_GNU_undef_indirect_alt and
DW_MACRO_GNU_transparent_include_alt.
* dwarf.c (dwarf_check): New global flag.
(fetch_indexed_string): New function.
(fetch_indexed_value): New function.
(get_FORM_name): Add DW_FORM_GNU_str_index and DW_FORM_GNU_addr_index.
(decode_location_expression): Add DW_OP_GNU_addr_index.
(read_and_display_attr_value): Add DW_FORM_GNU_str_index,
DW_FORM_GNU_addr_index, DW_AT_GNU_addr_base, and DW_AT_GNU_ranges_base.
(get_AT_name): Add new attributes for Fission.
(process_debug_info): Load new debug sections for Fission.
(load_debug_info): Check for .debug_info.dwo section.
(display_loc_list, display_loc_list_dwo): New functions.
(display_debug_loc): Move logic to above two functions.
(display_debug_info): Choose abbrev section based on info section.
(display_debug_types): Likewise.
(display_trace_info): Likewise.
(comp_addr_base): New function.
(display_debug_addr): New function.
(display_debug_str_offsets): New function.
(display_debug_ranges): Allow missing range lists. Suppress
diagnostics if dwarf_check not set.
(debug_displays): Add column to select abbrev section.
* dwarf.h (enum dwarf_section_display_enum): Add new debug sections
for Fission.
(struct dwarf_section): Add abbrev_sec field.
(struct dwarf_section_display): New type.
(debug_info): Add addr_base, ranges_base fields.
(dwarf_check): New global variable.
* objdump.c (usage): Add --dwarf-check option.
(enum option_values): Add OPTION_DWARF_CHECK.
(long_options): Add --dwarf-check.
(main): Likewise.
* readelf.c (OPTION_DWARF_CHECK): New macro.
(options): Add --dwarf-check.
(parse_args): Likewise.
(process_section_headers): Use const_strneq instead of
streq.
(read_and_display_attr_value): Print 8-byte forms as single hex
numbers.
(process_debug_info): Print type signatures as single hex numbers.
* elfcomm.c (byte_get_64): New function.
* elfcomm.h (byte_get_64): New function.
2011-10-04 Paul Woegerer <paul_woegerer@mentor.com>
Carlos O'Donell <carlos@codesourcery.com>
* dwarf.c (display_debug_lines_decoded): Index directory_table with
directory_index from file_table entry.
binutils/testsuite/
2011-10-04 Carlos O'Donell <carlos@codesourcery.com>
* binutils-all/dw2-decodedline.S: New file.
* binutils-all/objdump.WL: New file.
* binutils-all/objdump.exp: Update copyright year.
New test case for -WL.
* dwarf.c (decode_location_expression): For DW_OP_GNU_convert and
DW_OP_GNU_reinterpret, if uvalue is 0, don't add cu_offset.
Handle DW_OP_GNU_parameter_ref.
(loc_offsets_compar): New routine.
(display_debug_loc): Handle loc_offsets not being in ascending order
and also a single .debug_loc entry being used multiple times.
Use dwarf specific print functions to display these type values.
* dwarf.h (dwarf_signed_vma): New type;
(DWARF2_External_LineInfo): Replace bfd_vma by dwarf_vma.
(DWARF2_External_PubNames): Likewise.
(DWARF2_External_CompUnit): Likewise.
(DWARF2_External_ARange): Likewise.
(read_leb128): Change return type to dwarf_vma.
* dwarf.c (print_dwarf_vma): Use __MINGW32__ conditional and
check byte_size values.
(dwarf_vmatoa): Change parameter type to dwarf_vma.
(dwarf_svmatoa): New static function.
(read_leb128): Change return type to dwarf_vma.
(read_sleb128): New static function.
(struct State_Machine_Registers): Change address field type to
dwarf_vma.
(process_extended_line_op): Adapt to type changes.
(fetch_indirect_string): Likewise.
(idisplay_block): Likewise.
(decode_location_expression): Likewise.
(read_and_display_attr_value): Likewise.
(process_debug_info): Likewise.
(display_debug_lines_raw): Likewise.
(display_debug_lines_decoded): Likewise.
(SLEB macro): Use new read_sleb128 function.
* dwarf.c (decode_location_expression): Add offset_size and
dwarf_version arguments. Prefix DIE offset with 0x for
DW_OP_call{2,4,_ref}. Fix up DW_OP_call_ref operand size,
complain if in frame info section. Handle
DW_OP_GNU_implicit_pointer.
(read_and_display_attr_value, display_debug_loc,
display_debug_frames): Adjust decode_location_expression callers.
(process_debug_info): Save offset_size and dwarf_version values
into debug_information array.
* dwarf2.h (DW_OP_GNU_implicit_pointer): New.
(init_dwarf_regnames): Use them.
* dwarf.h: Declare them.
* objdump.c (dump_dwarf): Use bfd_get_arch + bfd_get_mach to set up
the regnames, rather than using elf_machine_code.
* elf-eh-frame.c (_bfd_elf_parse_eh_frame): Handle CIE version 4
provided that it has the expected address size and zero segment
length.
binutils/
* dwarf.c (struct Frame_Chunk): Add ptr_size and segment_size
fields.
(display_debug_frames): Handle CIE version 4.
* dwarf2.h (DWARF2_Internal_LineInfo): Add li_max_ops_per_insn
field.
bfd/
* dwarf2.c (struct line_head): Add maximum_ops_per_insn field.
(struct line_info): Add op_index field, change end_sequence type to
unsigned char.
(new_line_sorts_after): For the same address compare op_index.
(add_line_info): Add op_index argument, store it into the structure.
(decode_line_info): Complain about unknown versions of .debug_line.
Initialize maximum_ops_per_insn. Add op_index state register and
track it.
binutils/
* dwarf.c (struct State_Machine_Registers): Add op_index field,
change end_sequence type to unsigned char.
(reset_state_machine): Clear op_index.
(process_extended_line_op): For DW_LNE_set_address clear op_index.
(display_debug_lines_raw): Initialize li_max_ops_per_insn.
Track op_index state machine register and print it if
li_max_ops_per_insn is != 1.
(display_debug_lines_decoded): Likewise.
section in warning message.
(struct debug_display): Enable reloc processing for .debug_line
and .debug_ranges sections.
* readelf.c: Add --relocated-dump command line option to dump the
relocated contents of a specified section.
(request_dump): New function.
(parse_args): Use it.
(dump_section_as_bytes): Add parameter to indicate whether the
contents should be relocated.
(target_specific_reloc_handling): Add code for a R_MN10300_16
reloc found after a R_MN10300_SYM_DIFF reloc.
(debug_apply_relocations): Rename to apply_relocations.
(get_section_contents): New function. Replaces common code found
in dump_section_as_strings and dump_section_as_bytes.
* doc/binutils.texi: Document new command line option.
* NEWS: Mention the new feature.
Processes relocs in a target specific manner.
(debug_apply_relocations): Use the new function.
* dwarf.c (display_debug_loc): End the dump with a blank line.
(struct debug_display): Enable reloc processing for .debug_aranges
and .debug_loc sections.
