complie error: /usr/include/bpf/bpf_helpers.h:74:2: error: '#' is not followed by a macro parameter

[nlgwcy]

0. env:
   [root@localhost kmesh]# uname -r
   5.10.0-60.18.0.50.oe2203.x86_64
   [root@localhost kmesh]# yum info libbpf
   Last metadata expiration check: 22:58:20 ago on Fri 17 Nov 2023 11:45:50 AM CST.
   Installed Packages
   Name : libbpf
   Epoch : 2
   Version : 0.3
   Release : 1.h0.oe2203
   Architecture : x86_64
   Size : 239 k
   Source : libbpf-0.3-1.h0.oe2203.src.rpm
   Repository : @System
   From repo : everything
   Summary : Libbpf library
   URL : https://github.com/libbpf/libbpf
   License : LGPLv2 or BSD
   Description : A mirror of bpf-next linux tree bpf-next/tools/lib/bpf directory plus its
   : supporting header files. The version of the package reflects the version of
   : ABI.

[root@localhost kmesh]#

1. compile failed: complie error: /usr/include/bpf/bpf_helpers.h:74:2: error: '#' is not followed by a macro parameter
   [root@localhost kmesh]# ./build.sh
   ......
   In file included from ../../include/common.h:28:
   /usr/include/bpf/bpf_helpers.h:74:2: error: '#' is not followed by a macro parameter
   #if GNUC && !clang
   ^
   /usr/include/bpf/bpf_helpers.h:76:2: error: #else after #else
   #else
   ^
   /usr/include/bpf/bpf_helpers.h:80:2: error: #else after #else

2. After the preceding error is temporarily avoided, the following error message is displayed when the compilation continues:
   /home/wcy/code/kmesh/oncn-mda/ebpf_src/sock_redirect.c:23:31: error: use of undeclared identifier 'NULL'
   struct sock_key *redir_key = NULL;
   It looks like some basic header files are not included. pls check it, thanks.