From 734d86c9482d545f38c9c51e173d7f2287f521bf Mon Sep 17 00:00:00 2001 From: Martin Pitt Date: Fri, 11 Mar 2011 18:38:54 +0100 Subject: [PATCH] Avoid undefined division by zero Various division by zero operations in the test suite currently cause test failures on sparc64, as the compiler does not throw a SIGFPE like on most other platforms. Apply the already existing NULL returns from some division functions to int{8,82,84}div() as well, and update the comment to say that it isn't a gcc bug (see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29968 and http://www.open-std.org/jtc1/sc22/WG14/www/docs/n1256.pdf section 6.5.5 paragraph 5). Thanks to Aurelien Jarno for the initial patch! --- src/backend/utils/adt/int8.c | 16 ++++++++++++++-- 1 files changed, 14 insertions(+), 2 deletions(-) diff --git a/src/backend/utils/adt/int8.c b/src/backend/utils/adt/int8.c index bbab90c..d92b599 100644 --- a/src/backend/utils/adt/int8.c +++ b/src/backend/utils/adt/int8.c @@ -590,9 +590,13 @@ int8div(PG_FUNCTION_ARGS) int64 result; if (arg2 == 0) + { ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); + /* ensure we don't reach the division, as this is undefined */ + PG_RETURN_NULL(); + } result = arg1 / arg2; @@ -813,9 +817,13 @@ int84div(PG_FUNCTION_ARGS) int64 result; if (arg2 == 0) + { ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); + /* ensure we don't reach the division, as this is undefined */ + PG_RETURN_NULL(); + } result = arg1 / arg2; @@ -912,7 +920,7 @@ int48div(PG_FUNCTION_ARGS) ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); - /* ensure compiler realizes we mustn't reach the division (gcc bug) */ + /* ensure we don't reach the division, as this is undefined */ PG_RETURN_NULL(); } @@ -997,9 +1005,13 @@ int82div(PG_FUNCTION_ARGS) int64 result; if (arg2 == 0) + { ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); + /* ensure we don't reach the division, as this is undefined */ + PG_RETURN_NULL(); + } result = arg1 / arg2; @@ -1096,7 +1108,7 @@ int28div(PG_FUNCTION_ARGS) ereport(ERROR, (errcode(ERRCODE_DIVISION_BY_ZERO), errmsg("division by zero"))); - /* ensure compiler realizes we mustn't reach the division (gcc bug) */ + /* ensure we don't reach the division, as this is undefined */ PG_RETURN_NULL(); } -- 1.7.4.1