troubleshoot 32bit build

Author: jbrockmendel

pandas/core/groupby/ops.py

@@ -607,6 +607,14 @@ def _call_cython_op(
             # "rank" is the only member of cast_blocklist we get here
             res_dtype = self._get_result_dtype(orig_values.dtype)
             op_result = maybe_downcast_to_dtype(result, res_dtype)
+            if self.how == "first":
+                # troubleshooting 32bit linux build
+                assert res_dtype == orig_values.dtype, (res_dtype, orig_values.dtype)
+                assert op_result.dtype == res_dtype, (
+                    op_result.dtype,
+                    res_dtype,
+                    result,
+                )
         else:
             op_result = result