core: don't crash when clearing an already empty topology

bgoglin · bgoglin · commit db52ca9af081 · 2023-08-02T15:40:58.000+02:00
If all objects got removed because cgroups were wrong,
we'd crash when trying to clear the topology because the root
is already NULL.

Signed-off-by: Brice Goglin &lt;Brice.Goglin@inria.fr&gt;
diff --git a/hwloc/topology.c b/hwloc/topology.c
@@ -783,7 +783,8 @@ unlink_and_free_object_and_children(hwloc_obj_t *pobj)
 void
 hwloc_free_object_and_children(hwloc_obj_t obj)
 {
-  unlink_and_free_object_and_children(&obj);
+  if (obj)
+    unlink_and_free_object_and_children(&obj);
 }
 
 /* Free an object, its next siblings and their children without unlinking from parent.

Original file line number	Diff line number	Diff line change
`@@ -783,7 +783,8 @@ unlink_and_free_object_and_children(hwloc_obj_t *pobj)`
`783`	`783`	`void`
`784`	`784`	`hwloc_free_object_and_children(hwloc_obj_t obj)`
`785`	`785`	`{`
`786`		`- unlink_and_free_object_and_children(&obj);`
	`786`	`+ if (obj)`
	`787`	`+ unlink_and_free_object_and_children(&obj);`
`787`	`788`	`}`
`788`	`789`
`789`	`790`	`/* Free an object, its next siblings and their children without unlinking from parent.`