Message 75261 - Python tracker

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Author	mark.dickinson
Recipients	akitada, barry, christian.heimes, jnoller, loewis, mark.dickinson
Date	2008-10-27.20:26:44
SpamBayes Score	6.4706437e-06
Marked as misclassified	No
Message-id	<1225139205.75.0.189375157466.issue4204@psf.upfronthosting.co.za>
In-reply-to

Content
The test_math failure may well be due to a libm bug: tanh(-0.0) might be incorrectly (judging by the BSD man pages) dropping the negative sign from the negative zero. In the output of ./configure, there should be a line that looks like: checking whether tanh preserves the sign of zero... yes I'm guessing that on your machine you get a "no" instead of a "yes" there, indicating that tanh(-0.0) is 0.0 instead of -0.0 on your platform. Is this the case?

The test_math failure may well be due to a libm bug:  tanh(-0.0)
might be incorrectly (judging by the BSD man pages) dropping the negative 
sign from the negative zero.

In the output of ./configure, there should be a line that looks like:

checking whether tanh preserves the sign of zero... yes

I'm guessing that on your machine you get a "no" instead of a "yes"
there, indicating that tanh(-0.0) is 0.0 instead of -0.0 on your
platform.  Is this the case?

History
Date	User	Action	Args
2008-10-27 20:26:46	mark.dickinson	set	recipients: + mark.dickinson, loewis, barry, christian.heimes, jnoller, akitada
2008-10-27 20:26:45	mark.dickinson	set	messageid: <1225139205.75.0.189375157466.issue4204@psf.upfronthosting.co.za>
2008-10-27 20:26:45	mark.dickinson	link	issue4204 messages
2008-10-27 20:26:44	mark.dickinson	create