First of all, in order to build with clang at all, one must first apply Valentin Obst's build fix for LLVM [1]. Once that is done, then when building with clang, via: make LLVM=1 -C tools/testing/selftests ...clang generates warning here, because struct cpu_hogger has multiple fields, and the code is initializing an array of these structs, and it is incorrect to specify a single NULL value as the initializer. Fix this by initializing with {}, so that the compiler knows to use default initializer values for all fields in each array entry. [1] https://lore.kernel.org/all/20240329-selftests-libmk-llvm-rfc-v1-1-2f9ed7d1c49f@xxxxxxxxxxxxxxx/ Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx> --- tools/testing/selftests/cgroup/test_cpu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/cgroup/test_cpu.c b/tools/testing/selftests/cgroup/test_cpu.c index 24020a2c68dc..e4266b60e5ac 100644 --- a/tools/testing/selftests/cgroup/test_cpu.c +++ b/tools/testing/selftests/cgroup/test_cpu.c @@ -237,7 +237,7 @@ run_cpucg_weight_test( { int ret = KSFT_FAIL, i; char *parent = NULL; - struct cpu_hogger children[3] = {NULL}; + struct cpu_hogger children[3] = {}; parent = cg_name(root, "cpucg_test_0"); if (!parent) @@ -408,7 +408,7 @@ run_cpucg_nested_weight_test(const char *root, bool overprovisioned) { int ret = KSFT_FAIL, i; char *parent = NULL, *child = NULL; - struct cpu_hogger leaf[3] = {NULL}; + struct cpu_hogger leaf[3] = {}; long nested_leaf_usage, child_usage; int nprocs = get_nprocs(); -- 2.45.0