bpo-38858: new_interpreter() reuses _PySys_Create()

Include/internal/pycore_pylifecycle.h

@@ -40,7 +40,6 @@ extern PyObject * _PyBuiltin_Init(PyThreadState *tstate);
 extern PyStatus _PySys_Create(
  PyThreadState *tstate,
  PyObject **sysmod_p);
-extern PyStatus _PySys_SetPreliminaryStderr(PyObject *sysdict);
 extern PyStatus _PySys_ReadPreinitWarnOptions(PyWideStringList *options);
 extern PyStatus _PySys_ReadPreinitXOptions(PyConfig *config);
 extern int _PySys_InitMain(PyThreadState *tstate);

Python/pylifecycle.c

@@ -622,6 +622,8 @@ pycore_init_types(PyThreadState *tstate)
 static PyStatus
 pycore_init_builtins(PyThreadState *tstate)
 {
+ assert(!_PyErr_Occurred(tstate));
+
  PyObject *bimod = _PyBuiltin_Init(tstate);
  if (bimod == NULL) {
  goto error;
@@ -649,6 +651,9 @@ pycore_init_builtins(PyThreadState *tstate)
  goto error;
  }
  Py_DECREF(bimod);
+
+ assert(!_PyErr_Occurred(tstate));
+
  return _PyStatus_OK();
 
 error:
@@ -660,13 +665,14 @@ pycore_init_builtins(PyThreadState *tstate)
 static PyStatus
 pycore_init_import_warnings(PyThreadState *tstate, PyObject *sysmod)
 {
- const PyConfig *config = &tstate->interp->config;
+ assert(!_PyErr_Occurred(tstate));
 
  PyStatus status = _PyImportHooks_Init(tstate);
  if (_PyStatus_EXCEPTION(status)) {
  return status;
  }
 
+ const PyConfig *config = &tstate->interp->config;
  if (_Py_IsMainInterpreter(tstate)) {
  /* Initialize _warnings. */
  if (_PyWarnings_Init() == NULL) {
@@ -688,6 +694,9 @@ pycore_init_import_warnings(PyThreadState *tstate, PyObject *sysmod)
  return status;
  }
  }
+
+ assert(!_PyErr_Occurred(tstate));
+
  return _PyStatus_OK();
 }
 
@@ -929,6 +938,8 @@ _Py_ReconfigureMainInterpreter(PyThreadState *tstate)
 static PyStatus
 init_interp_main(PyThreadState *tstate)
 {
+ assert(!_PyErr_Occurred(tstate));
+
  PyStatus status;
  int is_main_interp = _Py_IsMainInterpreter(tstate);
  PyInterpreterState *interp = tstate->interp;
@@ -950,10 +961,10 @@ init_interp_main(PyThreadState *tstate)
  if (_PyTime_Init() < 0) {
  return _PyStatus_ERR("can't initialize time");
  }
+ }
 
- if (_PySys_InitMain(tstate) < 0) {
- return _PyStatus_ERR("can't finish initializing sys");
- }
+ if (_PySys_InitMain(tstate) < 0) {
+ return _PyStatus_ERR("can't finish initializing sys");
  }
 
  status = init_importlib_external(tstate);
@@ -1031,6 +1042,8 @@ init_interp_main(PyThreadState *tstate)
 #endif
  }
 
+ assert(!_PyErr_Occurred(tstate));
+
  return _PyStatus_OK();
 }
 
@@ -1534,70 +1547,40 @@ new_interpreter(PyThreadState **tstate_p)
 
  status = _PyConfig_Copy(&interp->config, config);
  if (_PyStatus_EXCEPTION(status)) {
- goto done;
+ goto error;
  }
  config = &interp->config;
 
  status = pycore_init_types(tstate);
-
- /* XXX The following is lax in error checking */
- PyObject *modules = PyDict_New();
- if (modules == NULL) {
- status = _PyStatus_ERR("can't make modules dictionary");
- goto done;
+ if (_PyStatus_EXCEPTION(status)) {
+ goto error;
  }
- interp->modules = modules;
 
- PyObject *sysmod = _PyImport_FindBuiltin(tstate, "sys");
- if (sysmod != NULL) {
- interp->sysdict = PyModule_GetDict(sysmod);
- if (interp->sysdict == NULL) {
- goto handle_exc;
- }
- Py_INCREF(interp->sysdict);
- PyDict_SetItemString(interp->sysdict, "modules", modules);
- if (_PySys_InitMain(tstate) < 0) {
- status = _PyStatus_ERR("can't finish initializing sys");
- goto done;
- }
- }
- else if (_PyErr_Occurred(tstate)) {
- goto handle_exc;
+ PyObject *sysmod;
+ status = _PySys_Create(tstate, &sysmod);
+ if (_PyStatus_EXCEPTION(status)) {
+ return status;
  }
 
  status = pycore_init_builtins(tstate);
  if (_PyStatus_EXCEPTION(status)) {
- goto done;
+ goto error;
  }
 
- if (sysmod != NULL) {
- status = _PySys_SetPreliminaryStderr(interp->sysdict);
- if (_PyStatus_EXCEPTION(status)) {
- goto done;
- }
-
- status = pycore_init_import_warnings(tstate, sysmod);
- if (_PyStatus_EXCEPTION(status)) {
- goto done;
- }
-
- status = init_interp_main(tstate);
- if (_PyStatus_EXCEPTION(status)) {
- goto done;
- }
+ status = pycore_init_import_warnings(tstate, sysmod);
+ if (_PyStatus_EXCEPTION(status)) {
+ goto error;
  }
 
- if (_PyErr_Occurred(tstate)) {
- goto handle_exc;
+ status = init_interp_main(tstate);
+ if (_PyStatus_EXCEPTION(status)) {
+ goto error;
  }
 
  *tstate_p = tstate;
  return _PyStatus_OK();
 
-handle_exc:
- status = _PyStatus_OK();
-
-done:
+error:
  *tstate_p = NULL;
 
  /* Oops, it didn't work. Undo it all. */

Python/sysmodule.c

@@ -2919,7 +2919,7 @@ _PySys_InitMain(PyThreadState *tstate)
  infrastructure for the io module in place.
 
  Use UTF-8/surrogateescape and ignore EAGAIN errors. */
-PyStatus
+static PyStatus
 _PySys_SetPreliminaryStderr(PyObject *sysdict)
 {
  PyObject *pstderr = PyFile_NewStdPrinter(fileno(stderr));
@@ -2946,11 +2946,13 @@ _PySys_SetPreliminaryStderr(PyObject *sysdict)
 PyStatus
 _PySys_Create(PyThreadState *tstate, PyObject **sysmod_p)
 {
+ assert(!_PyErr_Occurred(tstate));
+
  PyInterpreterState *interp = tstate->interp;
 
  PyObject *modules = PyDict_New();
  if (modules == NULL) {
- return _PyStatus_ERR("can't make modules dictionary");
+ goto error;
  }
  interp->modules = modules;
 
@@ -2961,13 +2963,13 @@ _PySys_Create(PyThreadState *tstate, PyObject **sysmod_p)
 
  PyObject *sysdict = PyModule_GetDict(sysmod);
  if (sysdict == NULL) {
- return _PyStatus_ERR("can't initialize sys dict");
+ goto error;
  }
  Py_INCREF(sysdict);
  interp->sysdict = sysdict;
 
  if (PyDict_SetItemString(sysdict, "modules", interp->modules) < 0) {
- return _PyStatus_ERR("can't initialize sys module");
+ goto error;
  }
 
  PyStatus status = _PySys_SetPreliminaryStderr(sysdict);
@@ -2980,10 +2982,17 @@ _PySys_Create(PyThreadState *tstate, PyObject **sysmod_p)
  return status;
  }
 
- _PyImport_FixupBuiltin(sysmod, "sys", interp->modules);
+ if (_PyImport_FixupBuiltin(sysmod, "sys", interp->modules) < 0) {
+ goto error;
+ }
+
+ assert(!_PyErr_Occurred(tstate));
 
  *sysmod_p = sysmod;
  return _PyStatus_OK();
+
+error:
+ return _PyStatus_ERR("can't initialize sys module");
 }