From 93ee1e3683a12f4774b8beb4f821910982e21ce2 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Thu, 24 Apr 2014 21:59:56 +0930 Subject: PR16867, linking object with separate debug file This teaches the DWARF2 find_line functions how to deal with separate debug relocatable object files. Also fixes a major bug: When _bfd_dwarf2_slurp_debug_info was split out, place_sections ran after .debug_info was relocated. This defeated the whole purpose of place_sections. See the comment I added before place_sections. Fixes some minor bugs too: - place_sections didn't set VMA for alloc but non-load sections (bss). - zero size sections can have symbols, so they need their VMA set too. - last_vma was incorrectly adjusted. - my last change to place_sections left VMA unchanged for .debug_info when the linker has mapped input to output sections, but this is wrong since bfd_simple_get_relocated_section_contents unmaps debug sections. PR 16867 * dwarf2.c: Formatting. (struct dwarf2_debug): Make adjusted_section_count signed. (unset_sections): Make i signed. (set_debug_vma): New function. (place_sections): Handle separate debug object file. Set VMA on debug sections, even if they have an output section. Also set VMA on zero size sections, and non-load but alloc sections. Set adjusted_section_count to -1 when no section adjustment. Malloc adjusted_sections. Don't double last_vma. Transfer alloc section VMAs to separate debug file. (_bfd_dwarf2_cleanup_debug_info): Free adjusted_sections. (_bfd_dwarf2_slurp_debug_info): Add do_place parameter. Drop test on symbols being the same before using old stash. Read and use separate debug file symbols. Call place_sections. (find_line): Don't call place_sections here. * libbfd-in.h (_bfd_dwarf2_slurp_debug_info): Update proto. * libbfd.h: Regenerate. * mach-o.c (bfd_mach_o_find_nearest_line): Adjust _bfd_dwarf2_slurp_debug_info call. * simple.c (simple_save_output_info): Clarify comment. --- bfd/simple.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) (limited to 'bfd/simple.c') diff --git a/bfd/simple.c b/bfd/simple.c index 55a5554..1331f9b 100644 --- a/bfd/simple.c +++ b/bfd/simple.c @@ -106,6 +106,22 @@ struct saved_offsets struct saved_output_info *sections; }; +/* The sections in ABFD may already have output sections and offsets + set if we are here during linking. + + DWARF-2 specifies offsets into debug sections in many cases and + bfd_simple_get_relocated_section_contents is called to relocate + debug info for a single relocatable object file. So we want + offsets relative to that object file's sections, not offsets in the + output file. For that reason, reset a debug section->output_offset + to zero. + + If not called during linking then set section->output_section to + point back to the input section, because output_section must not be + NULL when calling the relocation routines. + + Save the original output offset and section to restore later. */ + static void simple_save_output_info (bfd *abfd ATTRIBUTE_UNUSED, asection *section, @@ -220,15 +236,6 @@ bfd_simple_get_relocated_section_contents (bfd *abfd, outbuf = data; } - /* The sections in ABFD may already have output sections and offsets set. - Because this function is primarily for debug sections, and GCC uses the - knowledge that debug sections will generally have VMA 0 when emitting - relocations between DWARF-2 sections (which are supposed to be - section-relative offsets anyway), we need to reset the output offsets - to zero. We also need to arrange for section->output_section->vma plus - section->output_offset to equal section->vma, which we do by setting - section->output_section to point back to section. Save the original - output offset and output section to restore later. */ saved_offsets.section_count = abfd->section_count; saved_offsets.sections = malloc (sizeof (*saved_offsets.sections) * saved_offsets.section_count); -- cgit v1.1