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Author vstinner
Recipients mark.dickinson, r.david.murray, rhettinger, tim.peters, vstinner
Date 2022-02-05.16:42:34
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
> The big blocker here is that a platform that fully supports C99 might not define the "NAN" macro. I don't think we can require that NAN be defined in order for Python to build (which is what the PR currently does, if I'm understanding it correctly).

If a platform doesn't implement NaN, it should define the Py_NO_NAN macro:

/* Py_NAN
 * A value that evaluates to a NaN. On IEEE 754 platforms INF*0 or
 * INF/INF works. Define Py_NO_NAN in pyconfig.h if your platform
 * doesn't support NaNs.
#if !defined(Py_NAN) && !defined(Py_NO_NAN)
   // Use C99 "NAN" constant: quiet Not-A-Number (when supported)
#  define Py_NAN NAN

Or do you mean that a platform can support NaN but don't define the <math.h> NAN macro?
Date User Action Args
2022-02-05 16:42:34vstinnersetrecipients: + vstinner, tim.peters, rhettinger, mark.dickinson, r.david.murray
2022-02-05 16:42:34vstinnersetmessageid: <>
2022-02-05 16:42:34vstinnerlinkissue46640 messages
2022-02-05 16:42:34vstinnercreate