From 85c9dda818878149f3d248d5e09e03c4f26f436c Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 20 Oct 2023 13:40:15 -0400 Subject: [PATCH] Dodge a compiler bug affecting timetz_zone/timetz_izone. This avoids a compiler bug occurring in AIX's xlc, even in pretty late-model revisions. Buildfarm testing has now confirmed that only 64-bit xlc is affected. Although we are contemplating dropping support for xlc in v17, it's still supported in the back branches, so we need this fix. Back-patch of code changes from HEAD commit 19fa97731. (The test cases were already back-patched, in 4a427b82c et al.) Discussion: https://postgr.es/m/CA+hUKGK=DOC+hE-62FKfZy=Ybt5uLkrg3zCZD-jFykM-iPn8yw@mail.gmail.com --- src/backend/utils/adt/date.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/src/backend/utils/adt/date.c b/src/backend/utils/adt/date.c index 8690860cb7..eac296e318 100644 --- a/src/backend/utils/adt/date.c +++ b/src/backend/utils/adt/date.c @@ -3102,10 +3102,11 @@ timetz_zone(PG_FUNCTION_ARGS) result = (TimeTzADT *) palloc(sizeof(TimeTzADT)); result->time = t->time + (t->zone - tz) * USECS_PER_SEC; + /* C99 modulo has the wrong sign convention for negative input */ while (result->time < INT64CONST(0)) result->time += USECS_PER_DAY; - while (result->time >= USECS_PER_DAY) - result->time -= USECS_PER_DAY; + if (result->time >= USECS_PER_DAY) + result->time %= USECS_PER_DAY; result->zone = tz; @@ -3135,10 +3136,11 @@ timetz_izone(PG_FUNCTION_ARGS) result = (TimeTzADT *) palloc(sizeof(TimeTzADT)); result->time = time->time + (time->zone - tz) * USECS_PER_SEC; + /* C99 modulo has the wrong sign convention for negative input */ while (result->time < INT64CONST(0)) result->time += USECS_PER_DAY; - while (result->time >= USECS_PER_DAY) - result->time -= USECS_PER_DAY; + if (result->time >= USECS_PER_DAY) + result->time %= USECS_PER_DAY; result->zone = tz;