GameNetworkingSockets
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ValveSoftware
Multiplication result converted to larger type
https://github.com/ValveSoftware/GameNetworkingSockets/blob/725e273c7442bac7a8bc903c0b210b1c15c34d92/src/tier1/utlmemory.cpp#L21-L21
This rule finds code that converts the result of an integer multiplication to a larger type. Since the conversion applies after the multiplication, arithmetic overflow may still occur. The rule flags every multiplication of two non-constant integer expressions that is (explicitly or implicitly) converted to a larger integer type. The conversion is an indication that the expression would produce a result that would be too large to fit in the smaller integer type.
POC
int i = 2000000000;
long j = i * i; //Wrong: due to overflow on the multiplication between ints,
//will result to j being -1651507200, not 4000000000000000000
long k = (long) i * i; //Correct: the multiplication is done on longs instead of ints,
//and will not overflow
long l = static_cast<long>(i) * i; //Correct: modern C++
