[PATCH] selftests/powerpc: fix build error in powerpc ptrace selftests.

[Michael Ellerman]

wei.guo.simon at gmail.com writes:

> From: Simon Guo <wei.guo.simon at gmail.com>
>
> GCC 7 will take "r2" in clobber list as an error will it will get following
> build errors for powerpc ptrace selftests even with -fno-pic option:
>   ptrace-tm-vsx.c: In function ‘tm_vsx’:
>   ptrace-tm-vsx.c:42:2: error: PIC register clobbered by ‘r2’ in ‘asm’
>     asm __volatile__(
>     ^~~
>   make[1]: *** [ptrace-tm-vsx] Error 1
>   ptrace-tm-spd-vsx.c: In function ‘tm_spd_vsx’:
>   ptrace-tm-spd-vsx.c:55:2: error: PIC register clobbered by ‘r2’ in ‘asm’
>     asm __volatile__(
>     ^~~
>   make[1]: *** [ptrace-tm-spd-vsx] Error 1
>   ptrace-tm-spr.c: In function ‘tm_spr’:
>   ptrace-tm-spr.c:46:2: error: PIC register clobbered by ‘r2’ in ‘asm’
>     asm __volatile__(
>     ^~~
>
> This patch fix the build error by removing "r2" out of clobber list.

But do any of the blocks clobber r2? If so then it should be in the
clobber list.

cheers