Comment 5 for bug 1879360

Issue still exist in 5.6.0-1011.11

 Warning: Kernel ABI header at 'tools/include/uapi/linux/if_link.h' differs from latest version at 'include/uapi/linux/if_link.h'
 progs/test_xdp_bpf2bpf.c:11:18: warning: unknown attribute 'preserve_access_index' ignored [-Wunknown-attributes]
 } __attribute__((preserve_access_index));
 ^
 progs/test_xdp_bpf2bpf.c:19:18: warning: unknown attribute 'preserve_access_index' ignored [-Wunknown-attributes]
 } __attribute__((preserve_access_index));
 ^
 progs/test_xdp_bpf2bpf.c:28:18: warning: unknown attribute 'preserve_access_index' ignored [-Wunknown-attributes]
 } __attribute__((preserve_access_index));
 ^
 3 warnings generated.
 progs/test_core_reloc_bitfields_direct.c:53:13: error: use of unknown builtin '__builtin_preserve_field_info' [-Wimplicit-function-declaration]
 out->ub1 = BPF_CORE_READ_BITFIELD(in, ub1);
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:68:36: note: expanded from macro 'BPF_CORE_READ_BITFIELD'
 const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:23:2: note: expanded from macro '__CORE_RELO'
 __builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 ^
 progs/test_core_reloc_bitfields_direct.c:54:13: error: use of unknown builtin '__builtin_preserve_field_info' [-Wimplicit-function-declaration]
 out->ub2 = BPF_CORE_READ_BITFIELD(in, ub2);
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:68:36: note: expanded from macro 'BPF_CORE_READ_BITFIELD'
 const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:23:2: note: expanded from macro '__CORE_RELO'
 __builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 ^
 progs/test_core_reloc_bitfields_direct.c:55:13: error: use of unknown builtin '__builtin_preserve_field_info' [-Wimplicit-function-declaration]
 out->ub7 = BPF_CORE_READ_BITFIELD(in, ub7);
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:68:36: note: expanded from macro 'BPF_CORE_READ_BITFIELD'
 const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:23:2: note: expanded from macro '__CORE_RELO'
 __builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 ^
 progs/test_core_reloc_bitfields_direct.c:56:13: error: use of unknown builtin '__builtin_preserve_field_info' [-Wimplicit-function-declaration]
 out->sb4 = BPF_CORE_READ_BITFIELD(in, sb4);
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:68:36: note: expanded from macro 'BPF_CORE_READ_BITFIELD'
 const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:23:2: note: expanded from macro '__CORE_RELO'
 __builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 ^
 progs/test_core_reloc_bitfields_direct.c:57:14: error: use of unknown builtin '__builtin_preserve_field_info' [-Wimplicit-function-declaration]
 out->sb20 = BPF_CORE_READ_BITFIELD(in, sb20);
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:68:36: note: expanded from macro 'BPF_CORE_READ_BITFIELD'
 const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:23:2: note: expanded from macro '__CORE_RELO'
 __builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 ^
 progs/test_core_reloc_bitfields_direct.c:58:13: error: use of unknown builtin '__builtin_preserve_field_info' [-Wimplicit-function-declaration]
 out->u32 = BPF_CORE_READ_BITFIELD(in, u32);
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:68:36: note: expanded from macro 'BPF_CORE_READ_BITFIELD'
 const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:23:2: note: expanded from macro '__CORE_RELO'
 __builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 ^
 progs/test_core_reloc_bitfields_direct.c:59:13: error: use of unknown builtin '__builtin_preserve_field_info' [-Wimplicit-function-declaration]
 out->s32 = BPF_CORE_READ_BITFIELD(in, s32);
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:68:36: note: expanded from macro 'BPF_CORE_READ_BITFIELD'
 const void *p = (const void *)s + __CORE_RELO(s, field, BYTE_OFFSET); \
 ^
 /home/ubuntu/autotest/client/tmp/ubuntu_bpf/src/linux/tools/testing/selftests/bpf/tools/include/bpf/bpf_core_read.h:23:2: note: expanded from macro '__CORE_RELO'
 __builtin_preserve_field_info((src)->field, BPF_FIELD_##info)
 ^
 7 errors generated.
 llc-9: error: llc-9: :1:1: error: expected top-level entity
 BPF obj compilation failed
 ^