[20.8.1] gcc 9.3.1 can't build the source code

[tuxmaster5000]

The build on CentOS7 fails with:

cd /builddir/build/BUILD/openvas-20.8.1/my_build/misc && /usr/lib64/ccache/cc -DOPENVAS_DATA_DIR=\"/usr/share/openvas\" -DOPENVAS_FEED_LOCK_PATH=\"/run/greenbone/feed-update.lock\" -DOPENVAS_STATE_DIR=\"/var/lib/greenbone/lib/openvas\" -DOPENVAS_SYSCONF_DIR=\"/etc/openvas\" -Dopenvas_misc_shared_EXPORTS -I/usr/include/glib-2.0 -I/usr/lib64/glib-2.0/include -I/usr/include/gvm -I/usr/include/gvm-helper  -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1  -m64 -mtune=generic -D_FILE_OFFSET_BITS=64 -DLARGEFILE_SOURCE=1 -Wall -D_BSD_SOURCE -D_ISOC99_SOURCE -D_SVID_SOURCE -D_DEFAULT_SOURCE -Wall -Wextra -fPIC -g  -Werror -fPIC   -o CMakeFiles/openvas_misc_shared.dir/strutils.c.o   -c /builddir/build/BUILD/openvas-20.8.1/misc/strutils.c
In file included from /usr/include/string.h:638,
                 from /usr/include/glib-2.0/glib/gtestutils.h:30,
                 from /usr/include/glib-2.0/glib.h:82,
                 from /builddir/build/BUILD/openvas-20.8.1/misc/scanneraux.h:28,
                 from /builddir/build/BUILD/openvas-20.8.1/misc/network.h:29,
                 from /builddir/build/BUILD/openvas-20.8.1/misc/pcap.c:22:
In function 'strncpy',
    inlined from 'getinterfaces' at /builddir/build/BUILD/openvas-20.8.1/misc/pcap.c:461:7:
/usr/include/bits/string3.h:120:10: error: '__builtin_strncpy' output may be truncated copying 63 bytes from a string of length 10239 [-Werror=stringop-truncation]
  120 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function 'strncpy',
    inlined from 'getipv4routes' at /builddir/build/BUILD/openvas-20.8.1/misc/pcap.c:625:11:
/usr/include/bits/string3.h:120:10: error: '__builtin_strncpy' specified bound 64 equals destination size [-Werror=stringop-truncation]
  120 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function 'strncpy',
    inlined from 'routethrough' at /builddir/build/BUILD/openvas-20.8.1/misc/pcap.c:1117:15:
/usr/include/bits/string3.h:120:10: error: '__builtin_strncpy' specified bound 64 equals destination size [-Werror=stringop-truncation]
  120 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[2]: *** [misc/CMakeFiles/openvas_misc_shared.dir/pcap.c.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: Leaving directory `/builddir/build/BUILD/openvas-20.8.1/my_build'
make[1]: Leaving directory `/builddir/build/BUILD/openvas-20.8.1/my_build'
make[1]: *** [misc/CMakeFiles/openvas_misc_shared.dir/all] Error 2
make: *** [all] Error 2

When the source code is safe, then an gcc pragma statement can be used.

[tuxmaster5000]

The PR is only an hot fix, some one with deep source code knowledge can provide an better patch.