[sysprof] libsysprof: fix weak ref usage

[Christian Hergert <chergert src gnome org>]

commit eacdc47c341072454acf050c73d3acb1e0a6153a
Author: Christian Hergert <chergert redhat com>
Date:   Fri May 10 12:27:08 2019 -0700

    libsysprof: fix weak ref usage

 src/libsysprof/sysprof-helpers.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/libsysprof/sysprof-helpers.c b/src/libsysprof/sysprof-helpers.c
index d0dd026..87d0061 100644
--- a/src/libsysprof/sysprof-helpers.c
+++ b/src/libsysprof/sysprof-helpers.c
@@ -80,7 +80,7 @@ sysprof_helpers_get_default (void)
   if (g_once_init_enter (&instance))
     {
       SysprofHelpers *self = g_object_new (SYSPROF_TYPE_HELPERS, NULL);
-      g_object_add_weak_pointer (G_OBJECT (instance), (gpointer *)&instance);
+      g_object_add_weak_pointer (G_OBJECT (self), (gpointer *)&instance);
       g_once_init_leave (&instance, self);
     }