bpo-42323: Fix math.nextafter() for NaN on AIX (GH-24265)

vstinner · web-flow · commit c1c3493fb7a3 · 2021-01-20T15:20:13.000+01:00
diff --git a/Misc/NEWS.d/next/Library/2021-01-20-12-10-47.bpo-42323.PONB8e.rst b/Misc/NEWS.d/next/Library/2021-01-20-12-10-47.bpo-42323.PONB8e.rst
@@ -0,0 +1 @@
+Fix :func:`math.nextafter` for NaN on AIX.
diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c
@@ -3473,6 +3473,12 @@ math_nextafter_impl(PyObject *module, double x, double y)
            Bug fixed in bos.adt.libm 7.2.2.0 by APAR IV95512. */
         return PyFloat_FromDouble(y);
     }
+    if (Py_IS_NAN(x)) {
+        return x;
+    }
+    if (Py_IS_NAN(y)) {
+        return y;
+    }
 #endif
     return PyFloat_FromDouble(nextafter(x, y));
 }

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+Fix :func:`math.nextafter` for NaN on AIX.
Original file line number	Diff line number	Diff line change
`@@ -3473,6 +3473,12 @@ math_nextafter_impl(PyObject *module, double x, double y)`
`3473`	`3473`	`Bug fixed in bos.adt.libm 7.2.2.0 by APAR IV95512. */`
`3474`	`3474`	`return PyFloat_FromDouble(y);`
`3475`	`3475`	`}`
	`3476`	`+ if (Py_IS_NAN(x)) {`
	`3477`	`+ return x;`
	`3478`	`+ }`
	`3479`	`+ if (Py_IS_NAN(y)) {`
	`3480`	`+ return y;`
	`3481`	`+ }`
`3476`	`3482`	`#endif`
`3477`	`3483`	`return PyFloat_FromDouble(nextafter(x, y));`
`3478`	`3484`	`}`