On 15-09-16, 17:38, Arnd Bergmann wrote:
> When CONFIG_OPTIMIZE_INLINING is set and we are building with
> -Wmaybe-uninitialized
> enabled, we can get a warning for the opp core driver:
>
> drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate':
> drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used
> uninitialized in this function [-Wmaybe-uninitialized]
>
> This has only now appeared as a result of commit 797da5598f3a ("PM / devfreq:
> Add COMPILE_TEST for build coverage"), which makes the driver visible in
> some configurations that didn't have it before.
>
> The warning is a false positive that I got with gcc-6.1.1, but there is
> a simple workaround in removing the local variables that we get warnings
> for (all three are affected depending on the configuration). This also
> makes the code easier to read.
>
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
> ---
> drivers/base/power/opp/core.c | 10 +++-------
> 1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
> index df0c70963d9e..4c7c6da7a989 100644
> --- a/drivers/base/power/opp/core.c
> +++ b/drivers/base/power/opp/core.c
> @@ -584,7 +584,6 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long
> target_freq)
> struct clk *clk;
> unsigned long freq, old_freq;
> unsigned long u_volt, u_volt_min, u_volt_max;
> - unsigned long ou_volt, ou_volt_min, ou_volt_max;
> int ret;
>
> if (unlikely(!target_freq)) {
> @@ -620,11 +619,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned
> long target_freq)
> }
>
> old_opp = _find_freq_ceil(opp_table, &old_freq);
> - if (!IS_ERR(old_opp)) {
> - ou_volt = old_opp->u_volt;
> - ou_volt_min = old_opp->u_volt_min;
> - ou_volt_max = old_opp->u_volt_max;
> - } else {
> + if (IS_ERR(old_opp)) {
> dev_err(dev, "%s: failed to find current OPP for freq %lu
> (%ld)\n",
> __func__, old_freq, PTR_ERR(old_opp));
> }
> @@ -683,7 +678,8 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long
> target_freq)
> restore_voltage:
> /* This shouldn't harm even if the voltages weren't updated earlier */
> if (!IS_ERR(old_opp))
> - _set_opp_voltage(dev, reg, ou_volt, ou_volt_min, ou_volt_max);
> + _set_opp_voltage(dev, reg, old_opp->u_volt,
> + old_opp->u_volt_min, old_opp->u_volt_max);
>
> return ret;
> }
Acked-by: Viresh Kumar <viresh.ku...@linaro.org>
--
viresh
