cython compilation fixes

Author: rparolin

cuda_core/cuda/core/experimental/_device.pyx

@@ -1190,17 +1190,15 @@ class Device:
             True if other is a Device with the same device_id, False if not equal,
             NotImplemented if other is not a Device.
         """
-        # Use cast with exception handling instead of isinstance(other, Device)
+        # Use attribute access with exception handling instead of isinstance(other, Device)
         # for performance: isinstance with Python classes still involves type checking
-        # overhead. In contrast, a direct cast succeeds immediately in the common
+        # overhead. In contrast, a direct attribute access succeeds immediately in the common
         # case (other is a Device), and exception handling has very low overhead
         # when no exception occurs.
-        cdef Device _other
         try:
-            _other = <Device>other
-        except TypeError:
+            return self._id == other._id
+        except AttributeError:
             return NotImplemented
-        return self._id == _other._id
 
     def __reduce__(self):
         return Device, (self.device_id,)

cuda_core/cuda/core/experimental/_stream.pyx

@@ -148,12 +148,12 @@ cdef class Stream:
     @classmethod
     def _init(cls, obj: Optional[IsStreamT] = None, options=None, device_id: int = None):
         cdef Stream self = Stream.__new__(cls)
+        cdef cydriver.CUcontext ctx
+        cdef cydriver.CUresult err
 
         if obj is not None and options is not None:
             raise ValueError("obj and options cannot be both specified")
         if obj is not None:
-            cdef cydriver.CUcontext ctx
-            cdef cydriver.CUresult err
             self._handle = _try_to_get_stream_ptr(obj)
             # TODO: check if obj is created under the current context/device
             self._owner = obj
@@ -182,7 +182,6 @@ cdef class Stream:
             prio = high
 
         cdef cydriver.CUstream s
-        cdef cydriver.CUcontext ctx
         with nogil:
             HANDLE_RETURN(cydriver.cuStreamCreateWithPriority(&s, flags, prio))
             HANDLE_RETURN(cydriver.cuStreamGetCtx(s, &ctx))