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Date: Wed, 25 Jun 2014 09:09:08 -0700
From: Guenter Roeck <linux@roeck-us.net>
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        David Laight <David.Laight@ACULAB.COM>
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Subject: Re: [PATCH v2] sched: Fix compiler warnings
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On 06/25/2014 08:52 AM, Uwe Kleine-König wrote:
> Hello,
>
> On Wed, Jun 25, 2014 at 03:40:28PM +0000, David Laight wrote:
>> From: Guenter Roeck
>>> Actually turns out one can use __attribute_const__, and it is
>>>
>>> 	static inline int __attribute_const__ cpu_corepower_flags(void)
>>>
>>> which turns out to be widely used.
>>>
>>> I'll change that and resubmit after testing.
>>
>> You don't need to tell the compiler that for an inline function.
> I didn't check for the functions in question here, but in general your
> statement is wrong.
>
> For example:
>
> static inline unsigned int __attribute_const__ read_cpuid_id(void)
> {
> 	return readl(BASEADDR_V7M_SCB + V7M_SCB_CPUID);
> }
>
> from arch/arm/include/asm/cputype.h. The V7M_SCB_CPUID register never
> changes, but there is no way gcc can deduce that.
>

Sigh. As I mentioned earlier, it is much easier to introduce a problem
than to fix it.

Ok, I'll leave this alone. I already spent much more time on this than
I should or have, so it is really time to move on.

Guenter