On Thu, Jul 25, 2024 at 01:18:04PM -0700, Andrii Nakryiko wrote:
On Thu, Jul 25, 2024 at 3:39 AM Tony Ambardar tony.ambardar@gmail.com wrote:
From: Tony Ambardar tony.ambardar@gmail.com
Fix redefinition errors seen compiling lwt_reroute.c for mips64el/musl-libc by adjusting the order of includes in lwt_helpers.h. The ordering required is: <net/if.h> --> <arpa/inet.h> (from "test_progs.h") --> <linux/icmp.h>.
Because of the complexity and large number of includes, ordering appears to be fragile however. Previously, with "test_progs.h" at the end of this sequence, compiling with GCC 12.3 for mips64el/musl-libc yields errors:
In file included from .../include/arpa/inet.h:9, from ./test_progs.h:18, from tools/testing/selftests/bpf/prog_tests/lwt_helpers.h:11, from tools/testing/selftests/bpf/prog_tests/lwt_reroute.c:52: .../include/netinet/in.h:23:8: error: redefinition of 'struct in6_addr' 23 | struct in6_addr { | ^~~~~~~~ In file included from .../include/linux/icmp.h:24, from tools/testing/selftests/bpf/prog_tests/lwt_helpers.h:9: .../include/linux/in6.h:33:8: note: originally defined here 33 | struct in6_addr { | ^~~~~~~~ .../include/netinet/in.h:34:8: error: redefinition of 'struct sockaddr_in6' 34 | struct sockaddr_in6 { | ^~~~~~~~~~~~ .../include/linux/in6.h:50:8: note: originally defined here 50 | struct sockaddr_in6 { | ^~~~~~~~~~~~ .../include/netinet/in.h:42:8: error: redefinition of 'struct ipv6_mreq' 42 | struct ipv6_mreq { | ^~~~~~~~~ .../include/linux/in6.h:60:8: note: originally defined here 60 | struct ipv6_mreq { | ^~~~~~~~~
Similarly, with "test_progs.h" at the beginning of this sequence, compiling with GCC 12.3 for x86_64 using glibc would fail like this:
In file included from tools/testing/selftests/bpf/prog_tests/lwt_helpers.h:8, from tools/testing/selftests/bpf/prog_tests/lwt_reroute.c:52: /usr/include/linux/if.h:83:9: error: redeclaration of enumerator ‘IFF_UP’ 83 | IFF_UP = 1<<0, /* sysfs */ | ^~~~~~ /usr/include/net/if.h:44:5: note: previous definition of ‘IFF_UP’ with type ‘enum <anonymous>’ 44 | IFF_UP = 0x1, /* Interface is up. */ | ^~~~~~ /usr/include/linux/if.h:84:9: error: redeclaration of enumerator ‘IFF_BROADCAST’ 84 | IFF_BROADCAST = 1<<1, /* __volatile__ */ | ^~~~~~~~~~~~~ /usr/include/net/if.h:46:5: note: previous definition of ‘IFF_BROADCAST’ with type ‘enum <anonymous>’ 46 | IFF_BROADCAST = 0x2, /* Broadcast address valid. */ | ^~~~~~~~~~~~~
...
In file included from /usr/include/linux/icmp.h:23, from tools/testing/selftests/bpf/prog_tests/lwt_helpers.h:10, from tools/testing/selftests/bpf/prog_tests/lwt_reroute.c:52: /usr/include/linux/if.h:194:8: error: redefinition of ‘struct ifmap’ 194 | struct ifmap { | ^~~~~ In file included from tools/testing/selftests/bpf/prog_tests/lwt_helpers.h:8, from tools/testing/selftests/bpf/prog_tests/lwt_reroute.c:52: /usr/include/net/if.h:111:8: note: originally defined here 111 | struct ifmap | ^~~~~ In file included from /usr/include/linux/icmp.h:23, from tools/testing/selftests/bpf/prog_tests/lwt_helpers.h:10, from tools/testing/selftests/bpf/prog_tests/lwt_reroute.c:52: /usr/include/linux/if.h:232:8: error: redefinition of ‘struct ifreq’ 232 | struct ifreq { | ^~~~~ In file included from tools/testing/selftests/bpf/prog_tests/lwt_helpers.h:8, from tools/testing/selftests/bpf/prog_tests/lwt_reroute.c:52: /usr/include/net/if.h:126:8: note: originally defined here 126 | struct ifreq | ^~~~~
Fixes: 43a7c3ef8a15 ("selftests/bpf: Add lwt_xmit tests for BPF_REDIRECT") Signed-off-by: Tony Ambardar tony.ambardar@gmail.com
tools/testing/selftests/bpf/prog_tests/lwt_helpers.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h b/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h index fb1eb8c67361..8e5e28af03c5 100644 --- a/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h +++ b/tools/testing/selftests/bpf/prog_tests/lwt_helpers.h @@ -6,10 +6,9 @@ #include <time.h> #include <net/if.h> #include <linux/if_tun.h> +#include "test_progs.h" /* between <net/if.h> and <linux/icmp.h> or errors */
Now we'll be papering over the real issue. Can you see if you can untangle this mess and ensure that we consistently use either net/if.h or linux/if.h headers?
Well, "untangle this mess" is certainly the right phrase, so I'll give it another go and see what I can find.
pw-bot: cr
#include <linux/icmp.h>
-#include "test_progs.h"
#define log_err(MSG, ...) \ fprintf(stderr, "(%s:%d: errno: %s) " MSG "\n", \ __FILE__, __LINE__, strerror(errno), ##__VA_ARGS__) -- 2.34.1