Fix file/directory table count in pre-DWARF5 line table parsing#802
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portbuster1337 wants to merge 1 commit into
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Fix file/directory table count in pre-DWARF5 line table parsing#802portbuster1337 wants to merge 1 commit into
portbuster1337 wants to merge 1 commit into
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Bug: ctx->unit_dir and ctx->unit_file are never populated by the caller (rdi_from_dwarf_2.c), but dw2_read_line_table_header unconditionally pushed them as the first directory/file entries. This created an empty leading entry, making dirs.count and files.count one greater than the actual data. All subsequent directory indices and file indices were off by one. Fix: 1. Guard the first-entry pushes behind non-empty size checks in dw2_read_line_table_header (dwarf_parse_2.c). 2. Fix the file_index mapping in the line VM (rdi_from_dwarf_2.c): - Initialize file_index to 0 for DWARF 5, 1 for pre-DWARF5 - Convert 1-based file indices to 0-based array indices for pre-DWARF5 - Fix the bounds check to be correct for each version's indexing scheme
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Bug
ctx->unit_dirandctx->unit_fileinDW2_ParseCtxare never populated by the caller (rdi_from_dwarf_2.c), butdw2_read_line_table_headerunconditionally pushed them as the first directory and file entries for pre-DWARF5 line tables. This created an empty leading entry, makingdirs.countandfiles.countone greater than the actual data.Additionally,
DW_StdOpcode_Filein the line VM setsfile_indexto 1-based values for pre-DWARF5 and 0-based for DWARF 5, but the array lookup used the raw 1-based index directly on a 0-based array, and the initialfile_indexwas unconditionally set to 1 (wrong for DWARF 5 where it should be 0).Changes
src/dwarf/dwarf_parse_2.c: Guard the first-entry pushes behindsize != 0checks so the DWARF data's own entries stand on their own when the context fields are unpopulated.src/rdi_from_dwarf/rdi_from_dwarf_2.c:file_indexto 0 for DWARF 5, 1 for pre-DWARF5