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Specification changes: - Generic entrypoint now takes a single void* to a versioned data object (contract_violation_data_v1) instead of 6 individual params - Versioning rules: first byte is version, new versions append only, old runtimes ignore unknown fields - TU-local wrappers construct the versioned struct on the stack and call the generic entrypoint - Field type enumerators renamed with __cxa_field_ prefix - Removed field_summary (unused) - Fixed section numbering (5.3 → 5.2) - Fixed undefined contract_violation_field_t → __cxa_field_type_t - Replaced accessor API with sample implementations showing both runtime entrypoint and compiler-emitted pseudocode - Fixed std::contract_violation → std::contracts::contract_violation - Added TODO for handler linkage specification Other changes: - Added rationale.rst (design rationale, separated from spec) - Tightened requirements.rst (removed filler sections) - Reorganized index.rst (spec first, background second)
Runtime-provided wrappers (§4.2) conflict with the versioning strategy: they construct the versioned struct internally, locked to the runtime's version. A newer compiler wanting to pass v2 data cannot do so through an old runtime's wrapper. Requiring the compiler to always construct the versioned struct preserves forward compatibility. - Removed section 4.2 (runtime wrapper entrypoints) - Renumbered 4.3 → 4.2 (compiler-generated wrappers) - Added observed-semantic wrapper example alongside enforced - Removed runtime wrapper from sample implementation (§6.1) - Documented rationale for compiler-only wrappers
Includes: - contracts_abi.h: ABI types (__cxa_source_location, descriptor table, etc.) - contracts_runtime.cpp: runtime entrypoint + sample std::contracts::contract_violation - main.cpp: simulated compiler-emitted code exercising observed and enforced semantics - Makefile for building with clang++ The runtime demonstrates the key ABI flow: walking the descriptor table, extracting fields from static data, and constructing contract_violation using source_location::__create_from_pointer (matching libc++ layout). Also cleans up spec_answers_to_open_questions.rst (remove LLM artifacts, fix broken cross-references).
- GitHub Actions workflow to build and run the example, verifying contract violations print to stderr and the enforced check aborts - Link to the example directory from section 6 of the spec - Add efcs/cxx-abi as a submodule for the Itanium ABI patch - Gitignore the example binary and remove it from tracking
Each ABI type and enumeration now gets its own subsection with a dedicated code block and prose description, closer to how entities are specified in the C++ standard. Also adds a README linking to contracts-abi.com, the example directory, and the Itanium ABI patch.
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