小白求助，应该如何写出一个优雅的线程蓝图？

[St  K猫]

说明：某码农在写UE4蓝图的过程中发生了一件神奇的事，在接受了一坨端口传输的数据之后，竟然悲催地不能编译！！！
代码如下（省略串口调用）：
h:

UCLASS()
class MYPJT_API UmainBP : public UBlueprintFunctionLibrary
{
	GENERATED_BODY()
		UFUNCTION(BlueprintCallable, BlueprintPure, Category = Game)
		static FString BodyTurn
		(
			FString& LX_uparm,
			FString& LY_uparm,
			FString& LZ_uparm,
			FString& LZ_lowarm,
			FString& LX_hand,
			FString& LY_hand,
			FString& RX_uparm,
			FString& RY_uparm,
			FString& RZ_uparm,
			FString& RZ_lowarm,
			FString& RX_hand,
			FString& RY_hand
			);
};

cpp:

String UmainBP::BodyTurn(
    FString& LX_uparm,
    FString& LY_uparm,
    FString& LZ_uparm,
    FString& LZ_lowarm,
    FString& LX_hand,
    FString& LY_hand,
    FString& RX_uparm,
    FString& RY_uparm,
    FString& RZ_uparm,
    FString& RZ_lowarm,
    FString& RX_hand,
    FString& RY_hand
)
 
{
    int32_t wTempList[20] = { 0 }, i = 0;
    HANDLE hCom1 = init_com("COM3");
    char readBuf[1000] = { 0 }, bufTemp1[1024] = { 0 }, bufTemp2[1024] = { 0 };
    DWORD readsize;
    int n = 2;
    string str = "";
    int index = 0;
    while (n--) {
        ReadFile(hCom1, readBuf, 256, &readsize, NULL);
        str += readBuf;
        memset(readBuf, 0, sizeof(readBuf));
        index = str.find('\n');
        if (index < 0) {}
        else if (index == 113)
        {
            string p = str.substr(0, index + 1);

            if (p[0] == ':' && p[113] == '\n')
            {
                for (i = 0; i < 14; i++)
                {
                    wTempList[i] = strtoul(p.substr(i * 8 + 1, 8).c_str(), NULL, 16);
                }
                uint32_t crcData = wTempList[13];
                uint32_t crcRes = crc32_in_c(0, (uint8_t*)wTempList, 52);

            }
            index = 0;
            float lz_uparm = 180*wTempList[1]/32768;
            float ly_uparm = 180*wTempList[2]/32768;
            float lx_uparm = 180*wTempList[3]/32768;
            float lz_lowarm = 180*wTempList[4]/32768;
            float lx_hand = 180*wTempList[5]/32768;
            float ly_hand = 180*wTempList[6]/32768;
            float rz_uparm = 180*wTempList[7]/32768;
            float ry_uparm = 180*wTempList[8]/32768;
            float rx_uparm = 180*wTempList[9]/32768;
            float rz_lowarm = 180*wTempList[10]/32768;
            float rx_hand = 180*wTempList[11]/32768;
            float ry_hand = 180*wTempList[12]/32768;
            LZ_uparm = FString::SanitizeFloat(lz_uparm); 
            LY_uparm = FString::SanitizeFloat(ly_uparm);
            LX_uparm = FString::SanitizeFloat(lx_uparm);
            LZ_lowarm = FString::SanitizeFloat(lz_lowarm);
            LX_hand = FString::SanitizeFloat(lx_hand);
            LY_hand = FString::SanitizeFloat(ly_hand);
            RZ_uparm = FString::SanitizeFloat(rz_uparm);
            RY_uparm = FString::SanitizeFloat(ry_uparm);
            RX_uparm = FString::SanitizeFloat(rx_uparm);
            RZ_lowarm = FString::SanitizeFloat(rz_lowarm);
            RX_hand = FString::SanitizeFloat(rx_hand);
            RY_hand = FString::SanitizeFloat(ry_hand);
          
        }
        else
        {
            str.erase(0, index + 1);
            LZ_uparm = "0";
            LY_uparm = "0";
            LX_uparm = "0";
            LZ_lowarm = "0";
            LX_hand = "0";
            LY_hand = "0";
            RZ_uparm = "0";
            RY_uparm = "0";
            RX_uparm = "0";
            RZ_lowarm = "0";
            RX_hand = "0";
            RY_hand = "0";

        }
    }
    return "0";
}

于是在加载UE4，编译动画蓝图后，发生了以下悲剧：

求问诸位大神，这个不能运行由不报错的多线程安全该怎么破？