diff --git a/pandas/_libs/tslib.pyx b/pandas/_libs/tslib.pyx
index c5bc969ede3c9..ddeaffbfb3cc0 100644
--- a/pandas/_libs/tslib.pyx
+++ b/pandas/_libs/tslib.pyx
@@ -76,7 +76,8 @@ cdef inline object create_time_from_ts(
 
 @cython.wraparound(False)
 @cython.boundscheck(False)
-def ints_to_pydatetime(int64_t[:] arr, tz=None, freq=None, box="datetime"):
+def ints_to_pydatetime(int64_t[:] arr, object tz=None, object freq=None,
+                       str box="datetime"):
     """
     Convert an i8 repr to an ndarray of datetimes, date, time or Timestamp
 
@@ -104,8 +105,9 @@ def ints_to_pydatetime(int64_t[:] arr, tz=None, freq=None, box="datetime"):
         int64_t[:] deltas
         Py_ssize_t pos
         npy_datetimestruct dts
-        object dt
-        int64_t value, delta
+        object dt, new_tz
+        str typ
+        int64_t value, delta, local_value
         ndarray[object] result = np.empty(n, dtype=object)
         object (*func_create)(int64_t, npy_datetimestruct, object, object)
 
@@ -303,7 +305,8 @@ def format_array_from_datetime(ndarray[int64_t] values, object tz=None,
     return result
 
 
-def array_with_unit_to_datetime(ndarray values, unit, errors='coerce'):
+def array_with_unit_to_datetime(ndarray values, object unit,
+                                str errors='coerce'):
     """
     convert the ndarray according to the unit
     if errors:
@@ -458,10 +461,10 @@ def array_with_unit_to_datetime(ndarray values, unit, errors='coerce'):
 
 @cython.wraparound(False)
 @cython.boundscheck(False)
-cpdef array_to_datetime(ndarray[object] values, errors='raise',
-                        dayfirst=False, yearfirst=False,
-                        format=None, utc=None,
-                        require_iso8601=False):
+cpdef array_to_datetime(ndarray[object] values, str errors='raise',
+                        bint dayfirst=False, bint yearfirst=False,
+                        object format=None, object utc=None,
+                        bint require_iso8601=False):
     """
     Converts a 1D array of date-like values to a numpy array of either:
         1) datetime64[ns] data
@@ -510,9 +513,11 @@ cpdef array_to_datetime(ndarray[object] values, errors='raise',
         bint is_raise = errors=='raise'
         bint is_ignore = errors=='ignore'
         bint is_coerce = errors=='coerce'
+        bint is_same_offsets
         _TSObject _ts
+        int64_t value
         int out_local=0, out_tzoffset=0
-        float offset_seconds
+        float offset_seconds, tz_offset
         set out_tzoffset_vals = set()
 
     # specify error conditions
@@ -764,7 +769,7 @@ cpdef array_to_datetime(ndarray[object] values, errors='raise',
 @cython.wraparound(False)
 @cython.boundscheck(False)
 cdef array_to_datetime_object(ndarray[object] values, bint is_raise,
-                              dayfirst=False, yearfirst=False):
+                              bint dayfirst=False, bint yearfirst=False):
     """
     Fall back function for array_to_datetime