chore: use PyConfig.verbose/optimization_level on Python >= 3.12; fallback to legacy flags

Python 3.12 deprecates access to global flags like `Py_VerboseFlag` and
`Py_OptimizeFlag` in favor of per-interpreter config. Detect 3.12+ with
`PY_VERSION_HEX` and read `PyConfig.verbose` / `PyConfig.optimization_level`,
otherwise fall back to the legacy globals.

No functional change intended.

Co-authored-by: Jean-Christophe Fillion-Robin <[email protected]>

Author: hjmjohnson

src/PythonQtImporter.cpp

@@ -308,7 +308,11 @@ PythonQtImporter_load_module(PyObject *obj, PyObject *args)
     }
 
     Py_DECREF(code);
+#if PY_VERSION_HEX >= 0x030C0000  // Python >= 3.12
+    if (PyConfig.verbose) {
+#else
     if (Py_VerboseFlag) {
+#endif
       PySys_WriteStderr("import %s # loaded from %s\n",
         fullname, QStringToPythonConstCharPointer(fullPath));
     }
@@ -555,9 +559,14 @@ void PythonQtImport::writeCompiledModule(PyCodeObject *co, const QString& filena
   }
   fp = open_exclusive(filename);
   if (fp == nullptr) {
-    if (Py_VerboseFlag)
+#if PY_VERSION_HEX >= 0x030C0000  // Python >= 3.12
+    if (PyConfig.verbose) {
+#else
+    if (Py_VerboseFlag) {
+#endif
       PySys_WriteStderr(
       "# can't create %s\n", QStringToPythonConstCharPointer(filename));
+    }
     return;
   }
   PyMarshal_WriteLongToFile(PyImport_GetMagicNumber(), fp, Py_MARSHAL_VERSION);
@@ -566,8 +575,13 @@ void PythonQtImport::writeCompiledModule(PyCodeObject *co, const QString& filena
   PyMarshal_WriteLongToFile(sourceSize, fp, Py_MARSHAL_VERSION);
   PyMarshal_WriteObjectToFile((PyObject *)co, fp, Py_MARSHAL_VERSION);
   if (ferror(fp)) {
-    if (Py_VerboseFlag)
+#if PY_VERSION_HEX >= 0x030C0000  // Python >= 3.12
+    if (PyConfig.verbose) {
+#else
+    if (Py_VerboseFlag) {
+#endif
       PySys_WriteStderr("# can't write %s\n", QStringToPythonConstCharPointer(filename));
+    }
     /* Don't keep partial file */
     fclose(fp);
     QFile::remove(filename);
@@ -578,7 +592,11 @@ void PythonQtImport::writeCompiledModule(PyCodeObject *co, const QString& filena
   PyMarshal_WriteLongToFile(mtime, fp, Py_MARSHAL_VERSION);
   fflush(fp);
   fclose(fp);
+#if PY_VERSION_HEX >= 0x030C0000  // Python >= 3.12
+  if (PyConfig.verbose) {
+#else
   if (Py_VerboseFlag) {
+#endif
     PySys_WriteStderr("# wrote %s\n", QStringToPythonConstCharPointer(filename));
   }
 }
@@ -613,9 +631,14 @@ PythonQtImport::unmarshalCode(const QString& path, const QByteArray& data, time_
     time_t timeDiff = getLong((unsigned char *)buf + 4) - mtime;
     if (timeDiff<0) { timeDiff = -timeDiff; }
     if (timeDiff > 1) {
-      if (Py_VerboseFlag)
+#if PY_VERSION_HEX >= 0x030C0000  // Python >= 3.12
+      if (PyConfig.verbose) {
+#else
+      if (Py_VerboseFlag) {
+#endif
         PySys_WriteStderr("# %s has bad mtime\n",
         QStringToPythonConstCharPointer(path));
+      }
       Py_RETURN_NONE;
     }
   }
@@ -751,9 +774,14 @@ PythonQtImport::getModuleCode(PythonQtImporter *self, const char* fullname, QStr
     PyObject *code = nullptr;
     test = path + zso->suffix;
 
-    if (Py_VerboseFlag > 1)
+#if PY_VERSION_HEX >= 0x030C0000  // Python >= 3.12
+      if (PyConfig.verbose > 1) {
+#else
+      if (Py_VerboseFlag > 1) {
+#endif
       PySys_WriteStderr("# trying %s\n",
                         QStringToPythonConstCharPointer(test));
+    }
     if (PythonQt::importInterface()->exists(test)) {
       time_t mtime = 0;
       int ispackage = zso->type & IS_PACKAGE;
@@ -860,7 +888,11 @@ void PythonQtImport::init()
   mlab_searchorder[0].suffix[0] = SEP;
   mlab_searchorder[1].suffix[0] = SEP;
   mlab_searchorder[2].suffix[0] = SEP;
+#if PY_VERSION_HEX >= 0x030C0000  // Python >= 3.12
+  if (PyConfig.optimization_level) {
+#else
   if (Py_OptimizeFlag) {
+#endif
     /* Reverse *.pyc and *.pyo */
     struct st_mlab_searchorder tmp;
     tmp = mlab_searchorder[0];