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UBSan reported an unaligned uint64_t load in GpMurmurHash64A. Read each word with memcpy so input need not have uint64_t alignment, while preserving the little-endian hash computation. Sanitizer report (UBSan, instrumented build, ANALYZE on a table with short text values): gp_hyperloglog.c:897:11: runtime error: load of misaligned address 0x529000093515 for type 'uint64_t', which requires 8 byte alignment #0 GpMurmurHash64A gp_hyperloglog.c:897 #1 gp_hll_add_element gp_hyperloglog.c:471 #2 gp_hyperloglog_add_item gp_hyperloglog.c:788 #3 compute_scalar_stats commands/analyze.c:3968 #4 do_analyze_rel commands/analyze.c:971 #5 analyze_rel_internal commands/analyze.c:429 Triggered by ordinary ndistinct estimation during ANALYZE: short varlena values hashed via VARDATA_ANY have a payload offset that is not a multiple of 8. Benign on x86_64, but undefined behavior on strictly aligned targets.
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UBSan reported an unaligned uint64_t load in GpMurmurHash64A. Read each word with memcpy so input need not have uint64_t alignment, while preserving the little-endian hash computation.
Triggered by ordinary ndistinct estimation during ANALYZE: short varlena values hashed via VARDATA_ANY have a payload offset that is not a multiple of 8. Benign on x86_64, but undefined behavior on strictly aligned targets.
Fixes #ISSUE_Number
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make installcheckmake -C src/test installcheck-cbdb-parallelImpact
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