EXC_BAD_ACCESS错误

Question

我正在研究CUDD软件包，但在函数Cudd_DumpDot（下面的第一行）中崩溃到EXC_BAD_ACCESS错误中。发生什么事了？

retval = fprintf(fp,"digraph \"DD\" {\n");
if (retval == EOF) return(0);
retval = fprintf(fp,"size = \"7.5,10\"\ncenter = true;\nedge [dir = none];\n");
if (retval == EOF) return(0);