| Message ID | 20221217153821.2285-4-danieltimlee@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | samples/bpf: fix LLVM compilation warning with | expand |
On 12/17/22 7:38 AM, Daniel T. Lee wrote: > Currently, compiling samples/bpf with LLVM warns about the uninitialized > use of variable with test_current_task_under_cgroup. > > ./samples/bpf/test_current_task_under_cgroup_user.c:57:6: > warning: variable 'cg2' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] > if (setup_cgroup_environment()) > ^~~~~~~~~~~~~~~~~~~~~~~~~~ > ./samples/bpf/test_current_task_under_cgroup_user.c:106:8: > note: uninitialized use occurs here > close(cg2); > ^~~ > ./samples/bpf/test_current_task_under_cgroup_user.c:57:2: > note: remove the 'if' if its condition is always false > if (setup_cgroup_environment()) > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > ./samples/bpf/test_current_task_under_cgroup_user.c:19:9: > note: initialize the variable 'cg2' to silence this warning > int cg2, idx = 0, rc = 1; > ^ > = 0 > 1 warning generated. > > This commit resolve this compiler warning by pre-initialize the variable > with error for safeguard. > > Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com> Acked-by: Yonghong Song <yhs@fb.com>
diff --git a/samples/bpf/test_current_task_under_cgroup_user.c b/samples/bpf/test_current_task_under_cgroup_user.c index ac251a417f45..6fb25906835e 100644 --- a/samples/bpf/test_current_task_under_cgroup_user.c +++ b/samples/bpf/test_current_task_under_cgroup_user.c @@ -14,9 +14,9 @@ int main(int argc, char **argv) { pid_t remote_pid, local_pid = getpid(); + int cg2 = -1, idx = 0, rc = 1; struct bpf_link *link = NULL; struct bpf_program *prog; - int cg2, idx = 0, rc = 1; struct bpf_object *obj; char filename[256]; int map_fd[2]; @@ -103,7 +103,9 @@ int main(int argc, char **argv) rc = 0; err: - close(cg2); + if (cg2 != -1) + close(cg2); + cleanup_cgroup_environment(); cleanup:
Currently, compiling samples/bpf with LLVM warns about the uninitialized use of variable with test_current_task_under_cgroup. ./samples/bpf/test_current_task_under_cgroup_user.c:57:6: warning: variable 'cg2' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (setup_cgroup_environment()) ^~~~~~~~~~~~~~~~~~~~~~~~~~ ./samples/bpf/test_current_task_under_cgroup_user.c:106:8: note: uninitialized use occurs here close(cg2); ^~~ ./samples/bpf/test_current_task_under_cgroup_user.c:57:2: note: remove the 'if' if its condition is always false if (setup_cgroup_environment()) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./samples/bpf/test_current_task_under_cgroup_user.c:19:9: note: initialize the variable 'cg2' to silence this warning int cg2, idx = 0, rc = 1; ^ = 0 1 warning generated. This commit resolve this compiler warning by pre-initialize the variable with error for safeguard. Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com> --- samples/bpf/test_current_task_under_cgroup_user.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)