bpo-45272: os.path should not be a frozen module

Signed-off-by: Filipe Laíns <lains@riseup.net>

Author: FFY00

Lib/importlib/_bootstrap.py

@@ -263,7 +263,13 @@ def _requires_builtin_wrapper(self, fullname):
 def _requires_frozen(fxn):
     """Decorator to verify the named module is frozen."""
     def _requires_frozen_wrapper(self, fullname):
-        if not _imp.is_frozen(fullname):
+        if not _imp.is_frozen(fullname) or (
+            # bpo-45272: os.path is not a concrete module, but an importable
+            #            attribute of 'os'. _imp.is_frozen('os.path') returns
+            #            False but it is frozen, so we check the loader here.
+            fullname in sys.modules
+            and sys.modules[fullname].__spec__.loader is FrozenImporter
+        ):
             raise ImportError('{!r} is not a frozen module'.format(fullname),
                               name=fullname)
         return fxn(self, fullname)

Python/frozen.c

@@ -84,7 +84,6 @@ static const struct _frozen stdlib_modules[] = {
     {"genericpath", _Py_M__genericpath, (int)sizeof(_Py_M__genericpath)},
     {"ntpath", _Py_M__ntpath, (int)sizeof(_Py_M__ntpath)},
     {"posixpath", _Py_M__posixpath, (int)sizeof(_Py_M__posixpath)},
-    {"os.path", _Py_M__posixpath, (int)sizeof(_Py_M__posixpath)},
     {"os", _Py_M__os, (int)sizeof(_Py_M__os)},
     {"site", _Py_M__site, (int)sizeof(_Py_M__site)},
     {"stat", _Py_M__stat, (int)sizeof(_Py_M__stat)},
@@ -114,7 +113,6 @@ const struct _frozen *_PyImport_FrozenTest = test_modules;
 static const struct _module_alias aliases[] = {
     {"_frozen_importlib", "importlib._bootstrap"},
     {"_frozen_importlib_external", "importlib._bootstrap_external"},
-    {"os.path", "posixpath"},
     {"__hello_alias__", "__hello__"},
     {"__phello_alias__", "__hello__"},
     {"__phello_alias__.spam", "__hello__"},

Tools/scripts/freeze_modules.py

@@ -88,9 +88,6 @@ def find_tool():
         'genericpath',
         'ntpath',
         'posixpath',
-        # We must explicitly mark os.path as a frozen module
-        # even though it will never be imported.
-        f'{OS_PATH} : os.path',
         'os',
         'site',
         'stat',