On 04/28/17 02:44, Arnd Bergmann wrote:
> gcc warns that an empty device tree would cause undefined behavior:
>
> drivers/of/unittest.c: In function 'of_unittest':
> drivers/of/unittest.c:2199:25: warning: 'last_sibling' may be used
> uninitialized in this function [-Wmaybe-uninitialized]
>
> This adds an initialization of the variable to zero, which we handle
> correctly.
>
> Fixes: 81d0848fc8d2 ("of: Add unit tests for applying overlays")
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
> ---
> drivers/of/unittest.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
> index 12597ff8cfb0..6b8f3e6aa43c 100644
> --- a/drivers/of/unittest.c
> +++ b/drivers/of/unittest.c
> @@ -2192,7 +2192,7 @@ static __init void of_unittest_overlay_high_level(void)
>
> mutex_lock(&of_mutex);
>
> - for (np = of_root->child; np; np = np->sibling)
> + for (last_sibling = np = of_root->child; np; np = np->sibling)
> last_sibling = np;
>
> if (last_sibling)
>
Thanks Arnd! Linux-next also reported this and I sent Rob a different
patch for it yesterday.
Rob, I am fine with either Arnd's patch or mine, they both fix the
problem.
-Frank
