Runtime Error Processing WASM in ``` std::stof```?

Question

        [[eosio::action]]
        void hi(){
            string strNum;
            strNum.push_back('3');
            float currNum = std::stof(strNum);//  
            print("currNum=",currNum);
        }

then

MacBook-Plou:testkeys treaser$ cleos push action fy hi '[]' -p testhero@active
Error 3070002: Runtime Error Processing WASM
Error Details:
wabt execution failure (out of bounds memory access)
pending console output: 

Answer 1

I couldn't make that happen either but I did make this work:

std::string s("limit: 686.97");
float limit = atoi(s.c_str());
printf("limit [%f]\n", limit);

* Edit I *

of course, that gets us to integer. sadly the atof is not available, so I think counting the number of digits in the string, removing the dot, converting to an integer and then dividing by the number of digits would give the correct value. bloody mess

float _stof(std::string s)
{   
    std::size_t i = s.find(".");
    int digits = s.length() - i - 1;
    s.erase(i, 1);
    return atoi(s.c_str()) / pow(10, digits);
}