On Fri, Sep 15, 2017 at 09:55:18PM +0200, Arnd Bergmann wrote:
> We copy a local resource structure into a list, but only
> initialize some of its members, as pointed out by gcc-4.4:
>
> drivers/acpi/acpi_watchdog.c: In function 'acpi_watchdog_init':
> drivers/acpi/acpi_watchdog.c:105: error: 'res.child' may be used
> uninitialized in this function
> drivers/acpi/acpi_watchdog.c:105: error: 'res.sibling' may be used
> uninitialized in this function
> drivers/acpi/acpi_watchdog.c:105: error: 'res.parent' may be used
> uninitialized in this function
> drivers/acpi/acpi_watchdog.c:105: error: 'res.desc' may be used uninitialized
> in this function
> drivers/acpi/acpi_watchdog.c:105: error: 'res.name' may be used uninitialized
> in this function
>
> Newer compilers can presumably optimize the uninitialized access
> away entirely and don't warn at all, but rely on the kzalloc()
> to zero the structure first. This adds an explicit initialization
> to force consistent behavior.
>
> Fixes: 058dfc767008 ("ACPI / watchdog: Add support for WDAT hardware
> watchdog")
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
Acked-by: Guenter Roeck <li...@roeck-us.net>
> ---
> drivers/acpi/acpi_watchdog.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/acpi_watchdog.c b/drivers/acpi/acpi_watchdog.c
> index bf22c29d2517..11b113f8e367 100644
> --- a/drivers/acpi/acpi_watchdog.c
> +++ b/drivers/acpi/acpi_watchdog.c
> @@ -66,7 +66,7 @@ void __init acpi_watchdog_init(void)
> for (i = 0; i < wdat->entries; i++) {
> const struct acpi_generic_address *gas;
> struct resource_entry *rentry;
> - struct resource res;
> + struct resource res = {};
> bool found;
>
> gas = &entries[i].register_region;
> --
> 2.9.0
>
