I'm observing a few compiler warnings when building 2026b with MSVC 19.50.35726: ../pgsql/src/timezone/zic.c(353): warning C5287: operands are different enum types '<unnamed-enum-RF_NAME>' and '<unnamed-enum-LF_TARGET>'; use an explicit cast to silence this warning ../pgsql/src/timezone/zic.c(353): warning C5287: operands are different enum types '<unnamed-enum-RF_NAME>' and '<unnamed-enum-LP_YEAR>'; use an explicit cast to silence this warning This is with a somewhat modified file, but what it's pointing at is the same in the released 2026b sources: /* The maximum number of fields on any of the above lines. (The "+"s pacify gcc -Wenum-compare.) */ enum { MAX_FIELDS = max(max(+RULE_FIELDS, +LINK_FIELDS), max(+LEAP_FIELDS, +EXPIRES_FIELDS)) }; Perhaps instead of the "+"s, do explicit casts to int? ../pgsql/src/timezone/zic.c(1654): warning C4146: unary minus operator applied to unsigned type, result still unsigned This one is unhappy about /* The largest uintmax_t that is a multiple of BASE**6. Any random uintmax_t value that is this value or greater, yields a biased remainder when divided by BASE**6. UNFAIR_MIN equals the mathematical value of ((UINTMAX_MAX + 1) - (UINTMAX_MAX + 1) % BASE**6) computed without overflow. */ uint_fast64_t unfair_min = - ((UINTMAX_MAX % base__6 + 1) % base__6); Don't immediately have a suggestion about silencing this one. (This one is showing up on substantially older MSVC versions than the first two, as far back as MSVC 19.29.30159. I don't see these warnings on any non-Microsoft compiler.) regards, tom lane