Issue #28748: Private variable _Py_PackageContext is now of type "const char *"

rather of "char *".

Include/modsupport.h

@@ -176,7 +176,7 @@ PyAPI_FUNC(PyObject *) PyModule_FromDefAndSpec2(PyModuleDef *def,
 #endif /* New in 3.5 */
 
 #ifndef Py_LIMITED_API
-PyAPI_DATA(char *) _Py_PackageContext;
+PyAPI_DATA(const char *) _Py_PackageContext;
 #endif
 
 #ifdef __cplusplus

Misc/NEWS

@@ -416,6 +416,9 @@ Windows
 C API
 -----
 
+- Issue #28748: Private variable _Py_PackageContext is now of type "const char *"
+  rather of "char *".
+
 - Issue #19569: Compiler warnings are now emitted if use most of deprecated
   functions.
 

Objects/moduleobject.c

@@ -188,7 +188,7 @@ PyModule_Create2(struct PyModuleDef* module, int module_api_version)
        (if the name actually matches).
     */
     if (_Py_PackageContext != NULL) {
-        char *p = strrchr(_Py_PackageContext, '.');
+        const char *p = strrchr(_Py_PackageContext, '.');
         if (p != NULL && strcmp(module->m_name, p+1) == 0) {
             name = _Py_PackageContext;
             _Py_PackageContext = NULL;

Python/importdl.c

@@ -94,7 +94,7 @@ _PyImport_LoadDynamicModuleWithSpec(PyObject *spec, FILE *fp)
 #endif
     PyObject *name_unicode = NULL, *name = NULL, *path = NULL, *m = NULL;
     const char *name_buf, *hook_prefix;
-    char *oldcontext;
+    const char *oldcontext;
     dl_funcptr exportfunc;
     PyModuleDef *def;
     PyObject *(*p0)(void);

Python/modsupport.c

@@ -9,7 +9,7 @@ typedef double va_double;
 static PyObject *va_build_value(const char *, va_list, int);
 
 /* Package context -- the full module name for package imports */
-char *_Py_PackageContext = NULL;
+const char *_Py_PackageContext = NULL;
 
 /* Helper for mkvalue() to scan the length of a format */