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When compiling BPF selftests with -O2, GCC reports an array bounds
violation warning in global_map_resize test:
In function ‘global_map_resize_bss_subtest’,
inlined from ‘test_global_map_resize’ at /bpf-next/tools/testing/selftests/bpf/prog_tests/global_map_resize.c:228:3:
/bpf-next/tools/testing/selftests/bpf/prog_tests/global_map_resize.c:64:33: error: array subscript 1 is above array bounds of ‘int[1]’ [-Werror=array-bounds=]
64 | skel->bss->array[i] = 1;
| ~~~~~~~~~~~~~~~~^~~
In file included from /bpf-next/tools/testing/selftests/bpf/prog_tests/global_map_resize.c:6:
./test_global_map_resize.skel.h: In function ‘test_global_map_resize’:
./test_global_map_resize.skel.h:44:21: note: while referencing ‘array’
44 | int array[1];
| ^~~~~
This is a false positive because `array` (a BPF map) has been resized
from within the BPF program. GCC doesn't know that so let us silence the
warning by accessing the array via a plain pointer.
Fixes: 08b0895675 ("libbpf: Selftests for resizing datasec maps")
Signed-off-by: Viktor Malik <vmalik@redhat.com>
Link: https://lore.kernel.org/bpf/57765bc465a27923c3c093eba222cc24d08d8c40.1784112948.git.vmalik@redhat.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>