reinterpret_cast
cannot be used for this conversion, the code will not compile. According to C++03 standard section 5.2.10-1:
Conversions that can be performed explicitly using reinterpret_cast are listed below. No other conversion can be performed explicitly using reinterpret_cast.
This conversion is not listed in that section. Even this is invalid:
long l = reinterpret_cast(i)
static_cast
is the one which has to be used here. See this and this SO questions.