Build from source fails with GCC 15 and newer CMake

[aashish-thapa]

Summary

Building zvec from source fails on systems with GCC 15 and CMake 3.31+ (e.g., Arch Linux). Two separate issues in bundled third-party dependencies prevent compilation.

Environment

• OS: Arch Linux (kernel 6.18.6)
• GCC: 15.2.1
• CMake: 3.31.10
• Python: 3.14.2 (system), 3.12.12 (via pyenv)

Issue 1: antlr4 — CMAKE_POLICY(SET ... OLD) rejected by CMake 3.31+

thirdparty/antlr/antlr4/runtime/Cpp/CMakeLists.txt sets several policies to OLD:

CMAKE_POLICY(SET CMP0054 OLD)
CMAKE_POLICY(SET CMP0045 OLD)
CMAKE_POLICY(SET CMP0042 OLD)
CMAKE_POLICY(SET CMP0059 OLD)

CMake 3.31+ has removed support for the OLD behavior of these policies, causing a hard configuration error:

CMake Error at thirdparty/antlr/antlr4/runtime/Cpp/CMakeLists.txt:31 (CMAKE_POLICY):
CMake Error at thirdparty/antlr/antlr4/runtime/Cpp/CMakeLists.txt:32 (CMAKE_POLICY):
CMake Error at thirdparty/antlr/antlr4/runtime/Cpp/CMakeLists.txt:33 (CMAKE_POLICY):
CMake Error at thirdparty/antlr/antlr4/runtime/Cpp/CMakeLists.txt:38 (CMAKE_POLICY):
CMake Error at thirdparty/antlr/antlr4/runtime/Cpp/CMakeLists.txt:39 (CMAKE_POLICY):
-- Configuring incomplete, errors occurred!

Fix: Change OLD to NEW on lines 31-33 and 38-39.

Issue 2: RocksDB 8.1.1 — Type mismatches with GCC 15

RocksDB 8.1.1's trace_record.h and trace_record.cc have declaration mismatches under GCC 15. The compiler reports uint32_t/uint64_t resolving to int, causing errors like:

trace_replay/trace_record.cc:115:1: error: no declaration matches
  'rocksdb::IteratorSeekQueryTraceRecord::IteratorSeekQueryTraceRecord(SeekType, uint32_t, const std::string&, uint64_t)'

note: candidates are: '...(SeekType, int, const std::string&, int)'

This affects multiple classes: IteratorSeekQueryTraceRecord, MultiGetQueryTraceRecord, and their member functions.

Workaround

Building inside Docker with python:3.12 (which ships GCC 14) works after applying the antlr4 fix:

# 1. Patch antlr4 CMakeLists.txt (change OLD -> NEW on lines 31-33, 38-39)
# 2. Clean build dir
rm -rf build/ dist/

# 3. Build wheel in Docker
docker run --rm -v $(pwd):/src -w /src python:3.12 bash -c '
  git config --global --add safe.directory "*"
  pip wheel . -w /src/dist/ -v
'

# 4. Install in a Python 3.12 venv
~/.pyenv/versions/3.12.12/bin/python3.12 -m venv .venv
source .venv/bin/activate
pip install dist/zvec-*.whl

Suggestions

1. Update the antlr4 CMAKE_POLICY calls from OLD to NEW
2. Consider upgrading RocksDB to a version that compiles with GCC 15 (8.9+ or 9.x)
3. Update the build docs to specify supported compiler versions (GCC <= 14) rather than just "C++17 compatible compiler"
4. Consider adding Python 3.13+ to the supported versions or explicitly noting it's unsupported

[aashish-thapa]

also a quick share on what I had to do -> #143

[aashish-thapa]

just opened up pr with what fixed atleast one of the issue, @feihongxu0824. Great project. Love the Idea.