Debug, numba dose not understand how to extract dtype

strax/processing/general.py

@@ -82,9 +82,10 @@ def _overload_endtime(x):
 @numba.jit(nopython=True, nogil=True, cache=True)
 def diff(data):
     """Return time differences between items in data."""
+    # we are sure that time is np.int64
     if len(data) == 0:
-        return np.zeros(0, dtype=data.dtype["time"])
-    results = np.zeros(len(data) - 1, dtype=data.dtype["time"])
+        return np.zeros(0, dtype=np.int64)
+    results = np.zeros(len(data) - 1, dtype=np.int64)
     max_endtime = strax.endtime(data[0])
     for i, (time, endtime) in enumerate(zip(data["time"][1:], strax.endtime(data)[:-1])):
         results[i] = time - max_endtime