From 6d64b2394f269f412f5b6c02d22341e278641e20 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Thu, 3 Sep 2009 18:48:14 +0000 Subject: [PATCH] Install a workaround for a longstanding gcc bug that allows SIGFPE traps to occur for division by zero, even though the code is carefully avoiding that. All available evidence is that the only functions affected are int24div, int48div, and int28div, so patch just those three functions to include a "return" after the ereport() call. Backpatch to 8.4 so that the fix can be tested in production builds. For older branches our recommendation will continue to be to use -O1 on affected platforms (which are mostly non-mainstream anyway). --- src/backend/utils/adt/int.c | 5 +++++ src/backend/utils/adt/int8.c | 10 ++++++++++ 2 files changed, 15 insertions(+) diff --git a/src/backend/utils/adt/int.c b/src/backend/utils/adt/int.c index d6c946c327..548662f53a 100644 --- a/src/backend/utils/adt/int.c +++ b/src/backend/utils/adt/int.c @@ -950,9 +950,14 @@ int24div(PG_FUNCTION_ARGS) int32 arg2 = PG_GETARG_INT32(1); if (arg2 == 0) + { ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); + /* ensure compiler realizes we mustn't reach the division (gcc bug) */ + PG_RETURN_NULL(); + } + /* No overflow is possible */ PG_RETURN_INT32((int32) arg1 / arg2); } diff --git a/src/backend/utils/adt/int8.c b/src/backend/utils/adt/int8.c index 7d534a4cee..82d466c5ff 100644 --- a/src/backend/utils/adt/int8.c +++ b/src/backend/utils/adt/int8.c @@ -919,9 +919,14 @@ int48div(PG_FUNCTION_ARGS) int64 arg2 = PG_GETARG_INT64(1); if (arg2 == 0) + { ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); + /* ensure compiler realizes we mustn't reach the division (gcc bug) */ + PG_RETURN_NULL(); + } + /* No overflow is possible */ PG_RETURN_INT64((int64) arg1 / arg2); } @@ -1098,9 +1103,14 @@ int28div(PG_FUNCTION_ARGS) int64 arg2 = PG_GETARG_INT64(1); if (arg2 == 0) + { ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); + /* ensure compiler realizes we mustn't reach the division (gcc bug) */ + PG_RETURN_NULL(); + } + /* No overflow is possible */ PG_RETURN_INT64((int64) arg1 / arg2); } -- 2.30.2