Crun master fails to build in Ubuntu 16

[TeknoVenus]

The tip of crun (181135c) fails to build in Ubuntu 16.04.

Doing a git bisect shows the issue was introduced in 87b33ab

Build commands:

cd ~/crun
./autogen.sh
./configure --disable-systemd
sudo make install -j6

Output:

src/libcrun/ebpf.c: In function 'read_all_progs':
src/libcrun/ebpf.c:300:18: error: storage size of 'attr' isn't known
   union bpf_attr attr;
                  ^
src/libcrun/ebpf.c:312:32: error: 'BPF_CGROUP_DEVICE' undeclared (first use in this function)
       attr.query.attach_type = BPF_CGROUP_DEVICE;
                                ^
src/libcrun/ebpf.c:312:32: note: each undeclared identifier is reported only once for each function it appears in
src/libcrun/ebpf.c:316:13: warning: implicit declaration of function 'bpf' [-Wimplicit-function-declaration]
       ret = bpf (BPF_PROG_QUERY, &attr, sizeof (attr));
             ^
src/libcrun/ebpf.c:316:18: error: 'BPF_PROG_QUERY' undeclared (first use in this function)
       ret = bpf (BPF_PROG_QUERY, &attr, sizeof (attr));
                  ^
src/libcrun/ebpf.c: In function 'remove_all_progs':
src/libcrun/ebpf.c:332:18: error: storage size of 'attr' isn't known
   union bpf_attr attr;
                  ^
src/libcrun/ebpf.c:342:17: error: 'BPF_PROG_GET_FD_BY_ID' undeclared (first use in this function)
       fd = bpf (BPF_PROG_GET_FD_BY_ID, &attr, sizeof (attr));
                 ^
src/libcrun/ebpf.c:353:26: error: 'BPF_CGROUP_DEVICE' undeclared (first use in this function)
       attr.attach_type = BPF_CGROUP_DEVICE;
                          ^
src/libcrun/ebpf.c:357:18: error: 'BPF_PROG_DETACH' undeclared (first use in this function)
       ret = bpf (BPF_PROG_DETACH, &attr, sizeof (attr));
                  ^
src/libcrun/ebpf.c: In function 'ebpf_attach_program':
src/libcrun/ebpf.c:383:22: error: storage size of 'attr' isn't known
       union bpf_attr attr;
                      ^
src/libcrun/ebpf.c:411:26: error: 'BPF_CGROUP_DEVICE' undeclared (first use in this function)
       attr.attach_type = BPF_CGROUP_DEVICE;
                          ^
src/libcrun/ebpf.c:414:27: error: 'BPF_F_ALLOW_MULTI' undeclared (first use in this function)
       attr.attach_flags = BPF_F_ALLOW_MULTI;
                           ^
src/libcrun/ebpf.c:423:18: error: 'BPF_PROG_ATTACH' undeclared (first use in this function)
       ret = bpf (BPF_PROG_ATTACH, &attr, sizeof (attr));

[giuseppe]

fixed with: #401

[TeknoVenus]

Tested and builds fine with that PR. Thanks.