gcc trunk fails to build kernel on PowerPC64 due to oprofile warnings

[William Cohen]

On 01/25/2017 06:00 PM, Anton Blanchard wrote:
> Hi,
> 
> gcc trunk has failed to build PowerPC64 kernels for a month or so. The issue
> is in oprofile, which is common code but ends up being sucked into
> arch/powerpc and therefore subject to the -Werror applied to arch/powerpc:
>  
> linux/arch/powerpc/oprofile/../../../drivers/oprofile/oprofile_stats.c: In function ‘oprofile_create_stats_files’:
> linux/arch/powerpc/oprofile/../../../drivers/oprofile/oprofile_stats.c:55:25: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 7 [-Werror=format-truncation=]
>    snprintf(buf, 10, "cpu%d", i);
>                          ^~
> linux/arch/powerpc/oprofile/../../../drivers/oprofile/oprofile_stats.c:55:21: note: using the range [1, -2147483648] for directive argument
>    snprintf(buf, 10, "cpu%d", i);
>                      ^~~~~~~
> linux/arch/powerpc/oprofile/../../../drivers/oprofile/oprofile_stats.c:55:3: note: format output between 5 and 15 bytes into a destination of size 10
>    snprintf(buf, 10, "cpu%d", i);
>    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>   LD      crypto/async_tx/built-in.o
>   CC      lib/random32.o
> cc1: all warnings being treated as errors
> 
> Anton
> 
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> 

The attached patch should make the buffer large enough to eliminate the warning.

-Will
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