diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2017-04-19 19:47:04 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-27 09:10:38 +0200 |
| commit | 4420e5f323c408990834dddb61eb16e4a95a41e4 (patch) | |
| tree | 257a2f7ab27acc9ce4074904c165a610a07be05e | |
| parent | 11ba522d7929b9c319fd31d95bbc917baad9fe6f (diff) | |
ACPI / power: Avoid maybe-uninitialized warning
commit fe8c470ab87d90e4b5115902dd94eced7e3305c3 upstream.
gcc -O2 cannot always prove that the loop in acpi_power_get_inferred_state()
is enterered at least once, so it assumes that cur_state might not get
initialized:
drivers/acpi/power.c: In function 'acpi_power_get_inferred_state':
drivers/acpi/power.c:222:9: error: 'cur_state' may be used uninitialized in this function [-Werror=maybe-uninitialized]
This sets the variable to zero at the start of the loop, to ensure that
there is well-defined behavior even for an empty list. This gets rid of
the warning.
The warning first showed up when the -Os flag got removed in a bug fix
patch in linux-4.11-rc5.
I would suggest merging this addon patch on top of that bug fix to avoid
introducing a new warning in the stable kernels.
Fixes: 61b79e16c68d (ACPI: Fix incompatibility with mcount-based function graph tracing)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/acpi/power.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c index fcd4ce6f78d5..1c2b846c5776 100644 --- a/drivers/acpi/power.c +++ b/drivers/acpi/power.c @@ -200,6 +200,7 @@ static int acpi_power_get_list_state(struct list_head *list, int *state) return -EINVAL; /* The state of the list is 'on' IFF all resources are 'on'. */ + cur_state = 0; list_for_each_entry(entry, list, node) { struct acpi_power_resource *resource = entry->resource; acpi_handle handle = resource->device.handle; |