clang -O2  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations unistd/setresgid.c -o unistd/setresgid -D_POSIX_C_SOURCE=202405L  -lm  -lintl
unistd/setresgid.c:11:35: error: use of undeclared identifier 'setresgid'; did you mean 'setegid'?
int (*foo)(gid_t, gid_t, gid_t) = setresgid;
                                  ^~~~~~~~~
                                  setegid
/usr/include/unistd.h:179:6: note: 'setegid' declared here
int      setegid(gid_t);
         ^
unistd/setresgid.c:11:7: error: incompatible pointer types initializing 'int (*)(__gid_t, __gid_t, __gid_t)' with an expression of type 'int (__gid_t)' [-Werror,-Wincompatible-pointer-types]
int (*foo)(gid_t, gid_t, gid_t) = setresgid;
      ^                           ~~~~~~~~~
2 errors generated.