bpo-45412: Add _PY_SHORT_FLOAT_REPR macro (GH-31171)

Remove the HAVE_PY_SET_53BIT_PRECISION macro (moved to the internal
C API).

* Move HAVE_PY_SET_53BIT_PRECISION macro to pycore_pymath.h.
* Replace PY_NO_SHORT_FLOAT_REPR macro with _PY_SHORT_FLOAT_REPR
  macro which is always defined. gcc -Wundef emits a warning when
  using _PY_SHORT_FLOAT_REPR but the macro is not defined, if
  pycore_pymath.h include was forgotten.

2 files changed, 13 insertions, 11 deletions

diff --git a/Modules/cmathmodule.c b/Modules/cmathmodule.c
index 281d393..c0c0c35 100644
--- a/Modules/cmathmodule.c
+++ b/Modules/cmathmodule.c
@@ -7,7 +7,8 @@
 #endif
 
 #include "Python.h"
-#include "pycore_dtoa.h"
+#include "pycore_pymath.h"        // _PY_SHORT_FLOAT_REPR
+#include "pycore_dtoa.h"          // _Py_dg_stdnan()
 /* we need DBL_MAX, DBL_MIN, DBL_EPSILON, DBL_MANT_DIG and FLT_RADIX from
    float.h.  We assume that FLT_RADIX is either 2 or 16. */
 #include <float.h>
@@ -89,14 +90,14 @@ else {
 
 /* Constants cmath.inf, cmath.infj, cmath.nan, cmath.nanj.
    cmath.nan and cmath.nanj are defined only when either
-   PY_NO_SHORT_FLOAT_REPR is *not* defined (which should be
+   _PY_SHORT_FLOAT_REPR is 1 (which should be
    the most common situation on machines using an IEEE 754
    representation), or Py_NAN is defined. */
 
 static double
 m_inf(void)
 {
-#ifndef PY_NO_SHORT_FLOAT_REPR
+#if _PY_SHORT_FLOAT_REPR == 1
     return _Py_dg_infinity(0);
 #else
     return Py_HUGE_VAL;
@@ -112,12 +113,12 @@ c_infj(void)
     return r;
 }
 
-#if !defined(PY_NO_SHORT_FLOAT_REPR) || defined(Py_NAN)
+#if _PY_SHORT_FLOAT_REPR == 1 || defined(Py_NAN)
 
 static double
 m_nan(void)
 {
-#ifndef PY_NO_SHORT_FLOAT_REPR
+#if _PY_SHORT_FLOAT_REPR == 1
     return _Py_dg_stdnan(0);
 #else
     return Py_NAN;
@@ -1281,7 +1282,7 @@ cmath_exec(PyObject *mod)
                            PyComplex_FromCComplex(c_infj())) < 0) {
         return -1;
     }
-#if !defined(PY_NO_SHORT_FLOAT_REPR) || defined(Py_NAN)
+#if _PY_SHORT_FLOAT_REPR == 1 || defined(Py_NAN)
     if (PyModule_AddObject(mod, "nan", PyFloat_FromDouble(m_nan())) < 0) {
         return -1;
     }
@@ -1426,4 +1427,4 @@ PyMODINIT_FUNC
 PyInit_cmath(void)
 {
     return PyModuleDef_Init(&cmathmodule);
-}
\ No newline at end of file
+}
diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c
index 721c9a6..24ae146 100644
--- a/Modules/mathmodule.c
+++ b/Modules/mathmodule.c
@@ -62,6 +62,7 @@ raised for division by zero and mod by zero.
 #include "pycore_call.h"          // _PyObject_CallNoArgs()
 #include "pycore_dtoa.h"          // _Py_dg_infinity()
 #include "pycore_long.h"          // _PyLong_GetZero()
+#include "pycore_pymath.h"        // _PY_SHORT_FLOAT_REPR
 /* For DBL_EPSILON in _math.h */
 #include <float.h>
 /* For _Py_log1p with workarounds for buggy handling of zeros. */
@@ -272,7 +273,7 @@ lanczos_sum(double x)
 static double
 m_inf(void)
 {
-#ifndef PY_NO_SHORT_FLOAT_REPR
+#if _PY_SHORT_FLOAT_REPR == 1
     return _Py_dg_infinity(0);
 #else
     return Py_HUGE_VAL;
@@ -282,12 +283,12 @@ m_inf(void)
 /* Constant nan value, generated in the same way as float('nan'). */
 /* We don't currently assume that Py_NAN is defined everywhere. */
 
-#if !defined(PY_NO_SHORT_FLOAT_REPR) || defined(Py_NAN)
+#if _PY_SHORT_FLOAT_REPR == 1 || defined(Py_NAN)
 
 static double
 m_nan(void)
 {
-#ifndef PY_NO_SHORT_FLOAT_REPR
+#if _PY_SHORT_FLOAT_REPR == 1
     return _Py_dg_stdnan(0);
 #else
     return Py_NAN;
@@ -3837,7 +3838,7 @@ math_exec(PyObject *module)
     if (PyModule_AddObject(module, "inf", PyFloat_FromDouble(m_inf())) < 0) {
         return -1;
     }
-#if !defined(PY_NO_SHORT_FLOAT_REPR) || defined(Py_NAN)
+#if _PY_SHORT_FLOAT_REPR == 1 || defined(Py_NAN)
     if (PyModule_AddObject(module, "nan", PyFloat_FromDouble(m_nan())) < 0) {
         return -1;
     }