[PATCH] selftests/powerpc: Avoid GCC 12 uninitialised variable warning

GCC 12 thinks that `actual` might be used uninitialised. It's not, the
use is guarded by `bad_mmcr2` which is only set to true at the same
point where `actual` is initialised.

  cycles_with_mmcr2_test.c: In function ‘cycles_with_mmcr2’:
  cycles_with_mmcr2_test.c:81:17: error: ‘actual’ may be used uninitialized [-Werror=maybe-uninitialized]
     81 |                 printf("Bad MMCR2 value seen is 0x%lx\n", actual);

Silence the warning by initialising `actual` to zero.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
 tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c b/tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c
index 4b45a2e70f62..fc32187d483d 100644
--- a/tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c
+++ b/tools/testing/selftests/powerpc/pmu/ebb/cycles_with_mmcr2_test.c

@@ -50,6 +50,7 @@ int cycles_with_mmcr2(void)
 	expected[1] = MMCR2_EXPECTED_2;
 	i = 0;
 	bad_mmcr2 = false;
+	actual = 0;
 
 	/* Make sure we loop until we take at least one EBB */
 	while ((ebb_state.stats.ebb_count < 20 && !bad_mmcr2) ||

-- 
2.35.3

On Mon, 1 Aug 2022 21:37:46 +1000, Michael Ellerman wrote:

GCC 12 thinks that `actual` might be used uninitialised. It's not, the
use is guarded by `bad_mmcr2` which is only set to true at the same
point where `actual` is initialised.

  cycles_with_mmcr2_test.c: In function ‘cycles_with_mmcr2’:
  cycles_with_mmcr2_test.c:81:17: error: ‘actual’ may be used uninitialized [-Werror=maybe-uninitialized]
     81 |                 printf("Bad MMCR2 value seen is 0x%lx\n", actual);

[...]

Applied to powerpc/next.

[1/1] selftests/powerpc: Avoid GCC 12 uninitialised variable warning
      https://git.kernel.org/powerpc/c/ff446cd76854d47f451a84c26bb70934ae2ec5a7

cheers