Cast to union and weird number format
uint64_t flv_dbl2int( double value )
{
    return (union {double f; uint64_t i;}){value}.i;
}

uint64_t flv_dbl2int(double fvalue)
{
    uint64_t ivalue;
    memcpy(&ivalue, &fvalue, sizeof ivalue);
    return ivalue;
}

uint64_t flv_dbl2int(double value)
{
    return reinterpret_cast<uint64_t&>(value);
}

uint64_t flv_dbl2int( double value )
{
    union {double f; uint64_t i;} tmp = { value };
    return tmp.i;
}

uint64_t flv_dbl2int( double value )
{
  return *((uint64_t *) &value);
}

uint64_t flv_dbl2int( double value )
{
    union Foo {double f; uint64_t i;};
    return (*(Foo *)&value).i;
}