/in/foo.cc: In function 'int main()':
/in/foo.cc:11:22: warning: argument to 'sizeof' in 'void* memset(void*, int, size_t)' call is the same expression as the destination; did you mean to dereference it? [-Wsizeof-pointer-memaccess]
   memset(f1,0,sizeof f1);f1[1]=1;
                      ^~