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Re: "1 + -1" when rounding to -inf


David Miller <davem@davemloft.net> writes:

> From: Andreas Schwab <schwab@linux-m68k.org>
> Date: Mon, 21 Apr 2014 21:22:07 +0200
>
>> David Miller <davem@davemloft.net> writes:
>> 
>>> I wrote a simple test program and, with FE_DOWNWARD, the sequence is:
>>>
>>> -1 + 1 == -0.0L
>>>
>>> -1L / -0.0L == INF
>> 
>> Both are correct (the latter is independent of the rounding direction).
>
> The test case is expecting -INF.

The log functions always return -inf for Â0, so does log1p(-1).

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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