removed check for output guard in debug mode when cycle_detection is fast

theano/compile/debugmode.py

@@ -2272,25 +2272,26 @@ class _Maker(FunctionMaker):  # inheritance buys a few helper functions
                               "of", len(li), "events was stable.",
                               file=sys.stderr)
         self.fgraph = fgraph
-        destroy_handler_added = False
-        for feature in fgraph._features:
-            if isinstance(feature, gof.DestroyHandler):
-                destroy_handler_added = True
-                break
-        if not destroy_handler_added:
-            fgraph.attach_feature(gof.DestroyHandler())
-        for o in fgraph.outputs:
-            try:
-                with change_flags(compute_test_value=config.compute_test_value_opt):
-                    fgraph.replace_validate(o, _output_guard(o), reason='output_guard')
-                raise Exception("Output variable %s required output_guard, "
-                                "how was this output left unprotected against "
-                                "destructive operations?" % o)
-
-            except gof.InconsistencyError:
-                # This output is already impossible to destroy.
-                # No guard necessary
-                pass
+        if theano.config.cycle_detection == 'regular':
+            destroy_handler_added = False
+            for feature in fgraph._features:
+                if isinstance(feature, gof.DestroyHandler):
+                    destroy_handler_added = True
+                    break
+            if not destroy_handler_added:
+                fgraph.attach_feature(gof.DestroyHandler())
+            for o in fgraph.outputs:
+                try:
+                    with change_flags(compute_test_value=config.compute_test_value_opt):
+                        fgraph.replace_validate(o, _output_guard(o), reason='output_guard')
+                    raise Exception("Output variable %s required output_guard, "
+                                    "how was this output left unprotected against "
+                                    "destructive operations?" % o)
+
+                except gof.InconsistencyError:
+                    # This output is already impossible to destroy.
+                    # No guard necessary
+                    pass
 
         linker = _Linker(self)