clang-19 compatibility#46
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Adds a Make-driven regression that builds a small shared library with both clang and gcc at DWARF 4 and DWARF 5, runs abi-dumper against each, normalises the dumps (drops compiler-version metadata, renames DIE numeric IDs to stable T0001/T0002/... via structural traversal), and asserts the four dumps agree pairwise per DWARF version. Run with: make -C tests Override compilers with: make -C tests CLANG=clang-19 GCC=gcc-13 Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Two clang-emitted DWARF encodings that the 1.4 parser mishandled: * DW_TAG_subrange_type: DWARF 5 sec. 5.13 permits the bound to be encoded as DW_AT_count (number of elements) instead of DW_AT_upper_bound (highest index). gcc emits upper_bound; clang (>= 7) emits count for non-VLA C arrays. Previously only upper_bound was consulted, so fixed-size arrays from clang decayed to flexible arrays in the dump. Fall back to count when upper_bound is absent. * DW_FORM_sdata: eu-readelf renders sdata as "(sdata) RAW (SIGNED)" where RAW is the unsigned u64 reinterpretation and SIGNED is the signed value. The generic attribute reader only stripped the "(sdata) " form prefix, leaving "RAW (SIGNED)" as the stored value -- which broke negative enumerators (gcc and clang both use sdata for negative enumerator values). Capture the signed parenthesised value when this shape is seen. Regression covered by tests/. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Adds support for two Dwarf constructs that clang-19 emits.
Also adds a tests folder that checks that the fix works. The test needs both clang and gcc installed and not connected to CI in any way yet. Feel free to remove this folder if it doesn't fit the project's plans.
AI disclosure: Claude Opus 4.7 helped to make this PR.