thisisnic opened a new issue, #53945: URL: https://github.com/apache/arrow/issues/53945
### Describe the bug, including details regarding any error messages, version, and platform. The nightly `test-r-macos-as-cran` job has failed since October 13, 2026 because Arrow C++ no longer compiles with the MacOSX 11.3 SDK that CRAN uses. The libc++ in that SDK has `std::log2p1` but not `std::bit_width`. Failing run: https://github.com/ursacomputing/crossbow/actions/runs/38682228949 ``` cpp/src/arrow/util/alp/alp_compression.cc:203:65: error: no member named 'bit_width' in namespace 'std'; did you mean 'internal::UnpackOptions::bit_width'? cpp/src/arrow/util/alp/alp_compression.cc:448:38: error: no member named 'bit_width' in namespace 'std'; did you mean simply 'bit_width'? ``` The calls were added in #48345 (GH-48701): https://github.com/apache/arrow/blob/ca5564e007a209e251b9d4648af4bc6a53c68c4f/cpp/src/arrow/util/alp/alp_compression.cc#L203 https://github.com/apache/arrow/blob/ca5564e007a209e251b9d4648af4bc6a53c68c4f/cpp/src/arrow/util/alp/alp_compression.cc#L448 The existing call sites in `bit_util.h`, `chunker_internal.cc` and `encoder.cc` guard this with `#if defined(__apple_build_version__) && !defined(__cpp_lib_bitops)` and fall back to `std::log2p1`, e.g.: https://github.com/apache/arrow/blob/ca5564e007a209e251b9d4648af4bc6a53c68c4f/cpp/src/arrow/util/bit_util.h#L148 Regular macOS C++ CI does not catch this because only the as-cran job uses the 11.3 SDK. Rather than a fourth copy of the guard, a small `bit_util` helper wrapping it would let all call sites share one definition. Related: #49841. ### Component(s) C++ -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
