BUG: more nano fixes

pandas/src/engines.pyx

@@ -436,11 +436,11 @@ cdef class DatetimeEngine(Int64Engine):
 
 
 cdef inline _to_i8(object val):
+    cdef pandas_datetimestruct dts
     if util.is_datetime64_object(val):
         val = unbox_datetime64_scalar(val)
     elif PyDateTime_Check(val):
-        val = np.datetime64(val)
-        val = unbox_datetime64_scalar(val)
+        return _pydatetime_to_dts(val, &dts)
     return val
 
 # ctypedef fused idxvalue_t:

pandas/tseries/offsets.py

@@ -1007,6 +1007,10 @@ class Day(Tick, CacheableOffset):
     _inc = timedelta(1)
     _rule_base = 'D'
 
+    def isAnchored(self):
+
+        return False
+
 class Hour(Tick):
     _inc = timedelta(0, 3600)
     _rule_base = 'H'