diff options
Diffstat (limited to 'src/backend/utils/adt/float.c')
| -rw-r--r-- | src/backend/utils/adt/float.c | 46 |
1 files changed, 30 insertions, 16 deletions
diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c index 50ec3d3dde5..ffd1ce8c761 100644 --- a/src/backend/utils/adt/float.c +++ b/src/backend/utils/adt/float.c @@ -1088,18 +1088,25 @@ in_range_float8_float8(PG_FUNCTION_ARGS) } /* - * Deal with infinite offset (necessarily +inf, at this point). We must - * special-case this because if base happens to be -inf, their sum would - * be NaN, which is an overflow-ish condition we should avoid. + * Deal with cases where both base and offset are infinite, and computing + * base +/- offset would produce NaN. This corresponds to a window frame + * whose boundary infinitely precedes +inf or infinitely follows -inf, + * which is not well-defined. For consistency with other cases involving + * infinities, such as the fact that +inf infinitely follows +inf, we + * choose to assume that +inf infinitely precedes +inf and -inf infinitely + * follows -inf, and therefore that all finite and infinite values are in + * such a window frame. + * + * offset is known positive, so we need only check the sign of base in + * this test. */ - if (isinf(offset)) - { - PG_RETURN_BOOL(sub ? !less : less); - } + if (isinf(offset) && isinf(base) && + (sub ? base > 0 : base < 0)) + PG_RETURN_BOOL(true); /* * Otherwise it should be safe to compute base +/- offset. We trust the - * FPU to cope if base is +/-inf or the true sum would overflow, and + * FPU to cope if an input is +/-inf or the true sum would overflow, and * produce a suitably signed infinity, which will compare properly against * val whether or not that's infinity. */ @@ -1157,18 +1164,25 @@ in_range_float4_float8(PG_FUNCTION_ARGS) } /* - * Deal with infinite offset (necessarily +inf, at this point). We must - * special-case this because if base happens to be -inf, their sum would - * be NaN, which is an overflow-ish condition we should avoid. + * Deal with cases where both base and offset are infinite, and computing + * base +/- offset would produce NaN. This corresponds to a window frame + * whose boundary infinitely precedes +inf or infinitely follows -inf, + * which is not well-defined. For consistency with other cases involving + * infinities, such as the fact that +inf infinitely follows +inf, we + * choose to assume that +inf infinitely precedes +inf and -inf infinitely + * follows -inf, and therefore that all finite and infinite values are in + * such a window frame. + * + * offset is known positive, so we need only check the sign of base in + * this test. */ - if (isinf(offset)) - { - PG_RETURN_BOOL(sub ? !less : less); - } + if (isinf(offset) && isinf(base) && + (sub ? base > 0 : base < 0)) + PG_RETURN_BOOL(true); /* * Otherwise it should be safe to compute base +/- offset. We trust the - * FPU to cope if base is +/-inf or the true sum would overflow, and + * FPU to cope if an input is +/-inf or the true sum would overflow, and * produce a suitably signed infinity, which will compare properly against * val whether or not that's infinity. */ |