Re: [PATCH -tip] x86: cpu/intel_cacheinfo.c fix compilationwarnings

From: Ingo Molnar
Date: Tue Apr 14 2009 - 09:33:15 EST



* Jaswinder Singh Rajput <jaswinder@xxxxxxxxxx> wrote:

> fix:
> arch/x86/kernel/cpu/intel_cacheinfo.c: In function âshow_cache_disableâ:
> arch/x86/kernel/cpu/intel_cacheinfo.c:712: warning: unused variable ânodeâ
> arch/x86/kernel/cpu/intel_cacheinfo.c: In function âstore_cache_disableâ:
> arch/x86/kernel/cpu/intel_cacheinfo.c:739: warning: unused variable ânodeâ

you again 'fixed' a warning.

this made you fail to analyze and miss the real reason for this for
example:

> arch/x86/kernel/cpu/intel_cacheinfo.c:739: warning: unused variable ânodeâ

> - int node = cpu_to_node(cpu);

the local variable is clearly initialized.

The problem is not with that variable - the problem is most likely
with the cpu_to_node() macro not creating a reference to the 'cpu'
variable in a compiler-visible way, in the !NUMA case.

The typical way to solve this is to add a dummy:

(void)(cpu)

use to the 'cpu' parameter to the macro definition - or, (which is a
much better solution), to convert it to an inline function.

Ingo
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