Compilare: main.cpp: In function 'void prod(int&)': main.cpp:88:67: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] clone(callFFT, stack + STACK_SIZE, CLONE_VM | SIGCHLD, (void*)n); ^ main.cpp: In function 'char nextch()': main.cpp:39:58: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] if(pos==BUF_SIZE) fread(buf, BUF_SIZE, 1, fin), pos=0; ^