C++中malloc 有关的问题 求指教

Question

①
unsigned char * pBuf = (unsigned char*)env->GetByteArrayElements(b,0);
aes_encrypt(&ctx, pBuf, pBuf);
jbyteArray ret_ba = env->NewByteArray(16);
env->SetByteArrayRegion(ret_ba, 0, 16, (jbyte*)pBuf);
②
unsigned char * pBuf = (unsigned char*)env->GetByteArrayElements(b,0);
jbyte *pOutBuf = (jbyte*)malloc(16);
aes_encrypt(&ctx, pBuf, pOutBuf);
jbyteArray ret_ba = env->NewByteArray(16);
env->SetByteArrayRegion(ret_ba, 0, 16, (jbyte*)pOutBuf);

请问①和②就差了那么一行 为什么就解决了程序偶尔崩溃的问题

Answer 1

malloc设置了内存空间大小。空间不够就会崩溃