Warnings under GCC 7.2

[droark]

Hello. I'm getting some warnings under GCC 7.2 that I'm not getting under Xcode 9.2 (uses Clang 4.0, I believe). Any ideas on resolving them? I suppose I could pass in -Wno-attributes but I'd prefer to avoid that if possible.

Thanks.

droark@ubuntu:~/Projects/PersonalGitRepo/BitcoinArmory/cppForSwig/chacha20poly1305$ gcc -O3 -c poly1305.c chacha.c chachapoly_aead.c
In file included from poly1305.c:8:0:
poly1305.h:21:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__minbytes__, 4, POLY1305_KEYLEN)));
     ^~~~~~~~~~~~~
poly1305.h:21:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
poly1305.h:21:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
In file included from chacha.c:7:0:
chacha.h:26:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__minbytes__, 2, CHACHA_MINKEYLEN)));
     ^~~~~~~~~~~~~
chacha.h:29:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__minbytes__, 3, CHACHA_CTRLEN)));
     ^~~~~~~~~~~~~
chacha.h:29:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
chacha.h:33:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__buffer__, 3, 4)));
     ^~~~~~~~~~~~~
chacha.h:33:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
In file included from chachapoly_aead.h:4:0,
                 from chachapoly_aead.c:1:
chacha.h:26:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__minbytes__, 2, CHACHA_MINKEYLEN)));
     ^~~~~~~~~~~~~
chacha.h:29:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__minbytes__, 3, CHACHA_CTRLEN)));
     ^~~~~~~~~~~~~
chacha.h:29:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
chacha.h:33:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__buffer__, 3, 4)));
     ^~~~~~~~~~~~~
chacha.h:33:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
In file included from chachapoly_aead.c:4:0:
poly1305.h:21:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
     __attribute__((__bounded__(__minbytes__, 4, POLY1305_KEYLEN)));
     ^~~~~~~~~~~~~
poly1305.h:21:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]
poly1305.h:21:5: warning: ‘__bounded__’ attribute directive ignored [-Wattributes]