Disable the specialised "tp_getattro" implementations in Py3.7 as setting the...

Disable the specialised "tp_getattro" implementations in Py3.7 as setting the slot to anything but "PyObject_GenericGetAttr" disables the much more effective method call optimisation that avoids creating an intermediate PyMethod object in Py3.7.

Cython/Utility/ObjectHandling.c

@@ -1229,7 +1229,8 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_LookupSpecial(PyObject* obj, PyObj
 
 /////////////// PyObject_GenericGetAttrNoDict.proto ///////////////
 
-#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP
+// Setting "tp_getattro" to anything but "PyObject_GenericGetAttr" disables fast method calls in Py3.7.
+#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP && PY_VERSION_HEX < 0x03070000
 static CYTHON_INLINE PyObject* __Pyx_PyObject_GenericGetAttrNoDict(PyObject* obj, PyObject* attr_name);
 #else
 // No-args macro to allow function pointer assignment.
@@ -1238,7 +1239,7 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_GenericGetAttrNoDict(PyObject* obj
 
 /////////////// PyObject_GenericGetAttrNoDict ///////////////
 
-#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP
+#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP && PY_VERSION_HEX < 0x03070000
 
 static PyObject *__Pyx_RaiseGenericGetAttributeError(PyTypeObject *tp, PyObject *attr_name) {
     PyErr_Format(PyExc_AttributeError,
@@ -1289,7 +1290,8 @@ static CYTHON_INLINE PyObject* __Pyx_PyObject_GenericGetAttrNoDict(PyObject* obj
 
 /////////////// PyObject_GenericGetAttr.proto ///////////////
 
-#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP
+// Setting "tp_getattro" to anything but "PyObject_GenericGetAttr" disables fast method calls in Py3.7.
+#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP && PY_VERSION_HEX < 0x03070000
 static PyObject* __Pyx_PyObject_GenericGetAttr(PyObject* obj, PyObject* attr_name);
 #else
 // No-args macro to allow function pointer assignment.
@@ -1299,7 +1301,7 @@ static PyObject* __Pyx_PyObject_GenericGetAttr(PyObject* obj, PyObject* attr_nam
 /////////////// PyObject_GenericGetAttr ///////////////
 //@requires: PyObject_GenericGetAttrNoDict
 
-#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP
+#if CYTHON_USE_TYPE_SLOTS && CYTHON_USE_PYTYPE_LOOKUP && PY_VERSION_HEX < 0x03070000
 static PyObject* __Pyx_PyObject_GenericGetAttr(PyObject* obj, PyObject* attr_name) {
     if (unlikely(Py_TYPE(obj)->tp_dictoffset)) {
         return PyObject_GenericGetAttr(obj, attr_name);