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Date: Tue, 1 Sep 2015 18:40:46 +0000 (UTC)
From: Keith Busch <keith.busch@intel.com>
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To: Mark Brown <broonie@kernel.org>
cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>,
        Keith Busch <keith.busch@intel.com>, linux-kernel@vger.kernel.org,
        Liam Girdwood <lgirdwood@gmail.com>
Subject: Re: [PATCH] Regulator: Suppress compiler warnings
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On Tue, 1 Sep 2015, Mark Brown wrote:
> On Tue, Sep 01, 2015 at 09:52:13AM +0900, Krzysztof Kozlowski wrote:
>> 2015-09-01 1:41 GMT+09:00 Keith Busch <keith.busch@intel.com>:
>>>  int regulator_is_enabled_regmap(struct regulator_dev *rdev)
>>>  {
>>> -       unsigned int val;
>>> +       unsigned int uninitialized_var(val);
>>>         int ret;
>>>
>>>         ret = regmap_read(rdev->regmap, rdev->desc->enable_reg, &val);
>
>> This is quite common pattern so such work-around should be added to
>> many other functions leading to code obfuscation. Which compiler do
>> you have in mind?
>
> Right, plus this will shut up valid compiler warnings which is poor
> practice anyway.  I'd say this is a bug in the compiler.

Using gcc 4.7.2 with '-Os'. The warning does not happen when that option
is not used, i.e. disable CONFIG_CC_OPTIMIZE_FOR_SIZE.

I will certainly try other gcc versions with the same config and see
what happens.