[PATCH] of: guard pointers to key OF nodes with an #ifdef

[Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>]

We declare the pointers to some key OF-nodes unconditionally in
linux/of.h but only export them with CONFIG_OF=y. If anyone uses them in
code built without devicetree support enabled, the problem will only come
to light at link-time. Add an #ifdef guard to catch it at compile-time.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 include/linux/of.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/of.h b/include/linux/of.h
index 9bbdcf25a2b4..bc57dff819f8 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -138,10 +138,12 @@ static inline void of_node_put(struct device_node *node) { }
 DEFINE_FREE(device_node, struct device_node *, if (_T) of_node_put(_T))
 
 /* Pointer for first entry in chain of all nodes. */
+#if IS_ENABLED(CONFIG_OF)
 extern struct device_node *of_root;
 extern struct device_node *of_chosen;
 extern struct device_node *of_aliases;
 extern struct device_node *of_stdout;
+#endif
 
 /*
  * struct device_node flag descriptions
-- 
2.47.3