--- nono/vm/ethernet.cpp	2026/04/29 17:05:38	1.1.1.10
+++ nono/vm/ethernet.cpp	2026/04/29 17:05:43	1.1.1.11
@@ -34,7 +34,13 @@ EthernetDevice::Create()
 {
 	// ホストドライバを作成してこのデバイスと紐付ける
 	int n = GetId() - OBJ_ETHERNET0;
-	hostnet.reset(new HostNetDevice(this, n));
+	try {
+		hostnet.reset(new HostNetDevice(this, n));
+	} catch (...) { }
+	if ((bool)hostnet == false) {
+		warnx("Failed to initialize HostNetDevice(%u) at %s", n, __method__);
+		return false;
+	}
 
 	hostnet->SetRxCallback(ToDeviceCallback(&EthernetDevice::HostRxCallback));
 
@@ -129,11 +135,10 @@ EthernetDevice::CRC32(const uint8 *buf,
 	static const uint32 CRC_POLY = 0x04c11db6;
 	uint32 crc;
 	uint32 cy;
-	uint32 s;
 
 	crc = 0xffffffff;
 	for (size_t i = 0; i < buflen; i++) {
-		s = buf[i];
+		uint32 s = buf[i];
 		for (size_t j = 0; j < 8; j++) {
 			cy = ((crc & 0x80000000U) ? 0x01 : 0x00) ^ (s & 0x01);
 			crc <<= 1;
@@ -154,12 +159,11 @@ EthernetDevice::CRC32(const MacAddr& mac
 {
 	static const uint32 CRC_POLY = 0x04c11db6;
 	uint32 crc;
-	uint32 cy;
 	uint64 s = mac.Get();
 
 	crc = 0xffffffff;
 	for (size_t i = 0; i < mac.size() * 8; i++) {
-		cy = ((crc & 0x80000000U) ? 0x01 : 0x00) ^ (s & 0x01);
+		uint32 cy = ((crc & 0x80000000U) ? 0x01 : 0x00) ^ (s & 0x01);
 		crc <<= 1;
 		s >>= 1;
 		if (cy) {