Selftests fail to build on several distros/architectures because of
missing headers files.
On a Ubuntu/x86_64 some missing headers are:
asm/byteorder.h, asm/socket.h, asm/sockios.h
On a Debian/arm32 build already fails at sys/cdefs.h
In both cases, these already exist in /usr/include/<arch-specific-dir>,
but Clang does not include these when using '-target bpf' flag,
since it is no longer compiling against the host architecture.
The solution is to:
- run Clang without '-target bpf' and extract the include chain for the
current system
- add these to the bpf build with '-idirafter'
The choice of -idirafter is to catch this error without injecting
unexpected include behavior: if an arch-specific tree is built
for bpf in the future, this will be correctly found by Clang.
Signed-off-by: Sirio Balmelli <sirio@b-ad.ch>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
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