bpo-42260: Initialize time and warnings earlier at startup (GH-23249)

* Call _PyTime_Init() and _PyWarnings_InitState() earlier during the
  Python initialization.
* Inline _PyImportHooks_Init() into _PySys_InitCore().
* The _warnings initialization function no longer call
  _PyWarnings_InitState() to prevent resetting filters_version to 0.
* _PyWarnings_InitState() now returns an int and no longer clear the
  state in case of error (it's done anyway at Python exit).
* Rework init_importlib(), fix refleaks on errors.

3 files changed, 6 insertions, 3 deletions

diff --git a/Include/internal/pycore_interp.h b/Include/internal/pycore_interp.h
index 4b67a86..184878c 100644
--- a/Include/internal/pycore_interp.h
+++ b/Include/internal/pycore_interp.h
@@ -190,10 +190,14 @@ struct _is {
     struct _ceval_state ceval;
     struct _gc_runtime_state gc;
 
+    // sys.modules dictionary
     PyObject *modules;
     PyObject *modules_by_index;
+    // Dictionary of the sys module
     PyObject *sysdict;
+    // Dictionary of the builtins module
     PyObject *builtins;
+    // importlib module
     PyObject *importlib;
 
     /* Used in Modules/_threadmodule.c. */
@@ -218,7 +222,7 @@ struct _is {
 
     PyObject *builtins_copy;
     PyObject *import_func;
-    /* Initialized to PyEval_EvalFrameDefault(). */
+    // Initialized to _PyEval_EvalFrameDefault().
     _PyFrameEvalFunction eval_frame;
 
     Py_ssize_t co_extra_user_count;
diff --git a/Include/internal/pycore_pylifecycle.h b/Include/internal/pycore_pylifecycle.h
index 606252b..e748112 100644
--- a/Include/internal/pycore_pylifecycle.h
+++ b/Include/internal/pycore_pylifecycle.h
@@ -48,7 +48,6 @@ extern int _PySys_UpdateConfig(PyThreadState *tstate);
 extern PyStatus _PyExc_Init(PyThreadState *tstate);
 extern PyStatus _PyErr_Init(void);
 extern PyStatus _PyBuiltins_AddExceptions(PyObject * bltinmod);
-extern PyStatus _PyImportHooks_Init(PyThreadState *tstate);
 extern int _PyFloat_Init(void);
 extern PyStatus _Py_HashRandomization_Init(const PyConfig *);
 
diff --git a/Include/internal/pycore_warnings.h b/Include/internal/pycore_warnings.h
index cafe305..2a473b8 100644
--- a/Include/internal/pycore_warnings.h
+++ b/Include/internal/pycore_warnings.h
@@ -17,7 +17,7 @@ struct _warnings_runtime_state {
     long filters_version;
 };
 
-extern PyStatus _PyWarnings_InitState(PyThreadState *tstate);
+extern int _PyWarnings_InitState(PyThreadState *tstate);
 
 #ifdef __cplusplus
 }