> sp-1 will be NULL if sp pointer the first element in symbol > table, so > (sp-1)->value w! ill cause segment fault. > S! o I modify the code segment as follow: > if (sp->value > value) { > if (sp - st->symtable == 0) return NULL; > if (offset) > *offset = value - ((sp-1)->value); > return((struct syment *)(sp-1)); > } > Is that OK? I hope you could give me some advices. Looks good to me, although I would prefer "if (sp == st->symtable)" to make it a bit clearer.