Message 379979 - Python tracker

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Author	sree314
Recipients	sree314
Date	2020-10-30.16:04:29
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1604073869.82.0.718371202647.issue42210@roundup.psfhosted.org>
In-reply-to

Content
float.hex(float.fromhex("-nan")) returns 'nan'. PyOS_double_to_string seems to check only if it is a NaN, but ignores the sign (unlike its handling of inf a few lines below): <https://github.com/python/cpython/blob/e9e7d284c434768333fdfb53a3663eae74cb995a/Python/pystrtod.c#L903> Issue 5981 (https://bugs.python.org/issue5981) added the ability for fromhex to recognize -nan, but hex should probably have been updated at the same time. Encountered when testing float implementations.

float.hex(float.fromhex("-nan")) returns 'nan'.

PyOS_double_to_string seems to check only if it is a NaN, but ignores the sign (unlike its handling of inf a few lines below):

<https://github.com/python/cpython/blob/e9e7d284c434768333fdfb53a3663eae74cb995a/Python/pystrtod.c#L903>

Issue 5981 (https://bugs.python.org/issue5981) added the ability for fromhex to recognize -nan, but hex should probably have been updated at the same time.

Encountered when testing float implementations.

History
Date	User	Action	Args
2020-10-30 16:04:29	sree314	set	recipients: + sree314
2020-10-30 16:04:29	sree314	set	messageid: <1604073869.82.0.718371202647.issue42210@roundup.psfhosted.org>
2020-10-30 16:04:29	sree314	link	issue42210 messages
2020-10-30 16:04:29	sree314	create