https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178
--- Comment #23 from Alejandro Colomar <alx at kernel dot org> ---
If the attribute could be applied to a type, then you could apply it this way:
alx@debian:~/tmp/gcc$ cat nonstring.c
typeof(__attribute__((nonstring)) char [4]) tags[10];
alx@debian:~/tmp/gcc$ gcc -Wall -Wextra -S nonstring.c
nonstring.c:1:1: warning: ‘nonstring’ attribute does not apply to types
[-Wattributes]
1 | typeof(__attribute__((nonstring)) char [4]) tags[10];
| ^~~~~~
