Fix -Wnonnull build failure in TypedStats: value-initialize last_seen_val - #70
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Fix -Wnonnull build failure in TypedStats: value-initialize last_seen_val#70z0mz0m wants to merge 1 commit into
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TypedStats<PT> is explicitly instantiated for every PT in FLS_ALL_CTS, including str_pt. The member initializer last_seen_val(0) therefore instantiates as std::string(0) == std::string(nullptr), which is undefined behaviour; clang 21 diagnoses it as -Wnonnull and the build fails under -Werror: src/table/stats.cpp:17:21: error: null passed to a callee that requires a non-null argument [-Werror,-Wnonnull] Value-initializing instead gives 0 for the arithmetic instantiations and an empty string for str_pt, with no behaviour change for the numeric types. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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TypedStats<PT> is instantiated for str_pt via FLS_ALL_CTS, so last_seen_val(0) instantiated as std::string(nullptr) — UB, and fatal under -Werror with clang 21's -Wnonnull. Upstream PR: cwida#70 Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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TypedStats<PT>is explicitly instantiated for everyPTinFLS_ALL_CTS, includingstr_pt. The member initializerlast_seen_val(0)therefore instantiates asstd::string(0)==std::string(nullptr), which is undefined behaviour. Clang 21 diagnoses it and, with the project's-Werror, the build fails:Value-initializing with
{}yields0for the arithmetic instantiations and an empty string forstr_pt, so there is no behaviour change for the numeric types.Reproduced on: macOS 15 / arm64, Apple clang 21,
pip install .(scikit-build-core, Release). With this one-line change the wheel builds and a CSV ->.fls-> CSV roundtrip over ~112k rows x 7 BIGINT columns is byte-identical.🤖 Generated with Claude Code