Fix clang-cl build: avoid MSVC STL vectorized find on 16-byte StreamId - #30
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…clang-cl Building with the clang-cl presets against the latest MSVC STL (14.51) fails to compile CacheEngine.cpp: xutility(320): error: static assertion failed: unexpected size note: in instantiation of '_Find_vectorized<StreamCodec::StreamId, ...>' Under clang the MSVC STL trait `_Is_same_and_builtin_trivially_equality_comparable` uses the `__is_trivially_equality_comparable` builtin, which reports StreamId (two uint64_t, defaulted operator<=>) as eligible for the vectorized find fast path. That path (`_Find_vectorized`) only handles 1/2/4/8-byte elements and hard-errors on StreamId's 16 bytes. Plain MSVC `cl` hard-codes the trait to false, so only clang-cl trips over it. The identity-projected `std::ranges::find(wanted, p.id)` in StreamClaim's predicate was the sole trigger; the other find/count calls pass a projection (skipping the vectorized path) or search 8-byte/string ranges. Replace it with a predicate-based `std::ranges::none_of`, matching the idiom already used a few lines above, and comment why plain find is avoided. No behavior change; all clangcl-debug (830) and clangcl-release (828, smoke excluded) tests pass. Signed-off-by: Christian Parpart <c.parpart@lastrada.net>
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The
clangcl-debugandclangcl-releasepresets fail to compileCacheEngine.cppagainst the latest MSVC STL (14.51) with clang 22:Under clang, the MSVC STL trait
_Is_same_and_builtin_trivially_equality_comparableuses the__is_trivially_equality_comparablebuiltin, which reportsStreamId(twouint64_t, defaultedoperator<=>) as eligible for the vectorizedfindfast path. That path only handles 1/2/4/8-byte elements and hard-errors onStreamId's 16 bytes. Plain MSVCclhard-codes the trait tofalse, so only clang-cl trips over it.The identity-projected
std::ranges::find(wanted, p.id)inStreamClaim's predicate was the sole trigger — the otherfind/countcalls either pass a projection (which skips the vectorized path) or search 8-byte / string ranges. It is replaced with a predicate-basedstd::ranges::none_of, matching the idiom already used a few lines above, with a comment explaining why plainfindis avoided so it is not "simplified" back.No behavior change. All
clangcl-debug(830) andclangcl-release(828, smoke excluded) tests pass.