Add more missing PyErr_NoMemory() after failled memory allocs

Modules/_tkinter.c

@@ -2050,7 +2050,7 @@ Tkapp_CreateCommand(PyObject *_self, PyObject *args)
 
 	data = PyMem_NEW(PythonCmd_ClientData, 1);
 	if (!data)
-		return NULL;
+		return PyErr_NoMemory();
 	Py_XINCREF(self);
 	Py_XINCREF(func);
 	data->self = _self;

Modules/posixmodule.c

@@ -2251,7 +2251,7 @@ posix_execv(PyObject *self, PyObject *args)
 	argvlist = PyMem_NEW(char *, argc+1);
 	if (argvlist == NULL) {
 		PyMem_Free(path);
-		return NULL;
+		return PyErr_NoMemory();
 	}
 	for (i = 0; i < argc; i++) {
 		if (!PyArg_Parse((*getitem)(argv, i), "et",
@@ -2480,7 +2480,7 @@ posix_spawnv(PyObject *self, PyObject *args)
 	argvlist = PyMem_NEW(char *, argc+1);
 	if (argvlist == NULL) {
 		PyMem_Free(path);
-		return NULL;
+		return PyErr_NoMemory();
 	}
 	for (i = 0; i < argc; i++) {
 		if (!PyArg_Parse((*getitem)(argv, i), "et",

Objects/unicodeobject.c

@@ -6661,7 +6661,7 @@ unicode_subtype_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 	if (pnew->str == NULL) {
 		_Py_ForgetReference((PyObject *)pnew);
 		PyObject_Del(pnew);
-		return NULL;
+		return PyErr_NoMemory();
 	}
 	Py_UNICODE_COPY(pnew->str, tmp->str, n+1);
 	pnew->length = n;