Is there a general way to check for an overflow or an underflow of a given data type (uint32, int etc.)?
I am doing something like this:
uint32 a,b,c;
... //initialize a,b,c
if(b < c) {
a -= (c - b)
}
When I print a after some iterations, it displays a large number like: 4294963846.
Write a “C” function, int addOvf(int* result, int a, int b) If there is no overflow, the function places the resultant = sum a+b in “result” and returns 0. Otherwise it returns -1. The solution of casting to long and adding to find detecting the overflow is not allowed.
An integer overflow occurs when you attempt to store inside an integer variable a value that is larger than the maximum value the variable can hold. The C standard defines this situation as undefined behavior (meaning that anything might happen).
To check for over/underflow in arithmetic check the result compared to the original values.
uint32 a,b;
//assign values
uint32 result = a + b;
if (result < a) {
//Overflow
}
For your specific the check would be:
if (a > (c-b)) {
//Underflow
}
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