gh-119613: Soft deprecate Py_IS_NAN/INFINITY/FINITE (#119701)

Co-authored-by: Hugo van Kemenade <[email protected]>
Co-authored-by: Erlend E. Aasland <[email protected]>
Co-authored-by: Victor Stinner <[email protected]>

Author: 4 people

Doc/whatsnew/3.14.rst

@@ -231,6 +231,12 @@ Porting to Python 3.14
 Deprecated
 ----------
 
+* Macros :c:macro:`!Py_IS_NAN`, :c:macro:`!Py_IS_INFINITY`
+  and :c:macro:`!Py_IS_FINITE` are :term:`soft deprecated`,
+  use instead :c:macro:`!isnan`, :c:macro:`!isinf` and
+  :c:macro:`!isfinite` available from :file:`math.h`
+  since C99.  (Contributed by Sergey B Kirpichev in :gh:`119613`.)
+
 Removed
 -------
 

Include/pymath.h

@@ -29,14 +29,17 @@
 
 // Py_IS_NAN(X)
 // Return 1 if float or double arg is a NaN, else 0.
+// Soft deprecated since Python 3.14, use isnan() instead.
 #define Py_IS_NAN(X) isnan(X)
 
 // Py_IS_INFINITY(X)
 // Return 1 if float or double arg is an infinity, else 0.
+// Soft deprecated since Python 3.14, use isinf() instead.
 #define Py_IS_INFINITY(X) isinf(X)
 
 // Py_IS_FINITE(X)
 // Return 1 if float or double arg is neither infinite nor NAN, else 0.
+// Soft deprecated since Python 3.14, use isfinite() instead.
 #define Py_IS_FINITE(X) isfinite(X)
 
 // Py_INFINITY: Value that evaluates to a positive double infinity.

Misc/NEWS.d/next/C API/2024-05-29-09-21-37.gh-issue-119613.J2xfrC.rst

@@ -0,0 +1,2 @@
+Macros ``Py_IS_NAN``, ``Py_IS_INFINITY`` and ``Py_IS_FINITE``
+are :term:`soft deprecated`.