This is really weird. If I increase the value of asize
just by one crashSystem()
does what its name speaks. Second function returning an int pointer works ok with much bigger values. Those two functions just delete and allocate the same dynamic array with same size (I created it just for test purposes).
Note: I think it could have something to do with maximum stack capacity 1MB (130037 * 8 in bytes is near 1MB), but it's really strange 'cause allocating using new
inside function should work the same as any other new
.
Using Visual Studio 2015
#include <iostream>
void crashSystem(int * dynamicArray, int asize) {
delete[] dynamicArray;
//dynamicArray = nullptr; does not matter at all
dynamicArray = new int[asize];
std::cout << "mem allocated\n";
}
int * worksOk(int * dynamicArray, int asize) {
int * newDynamicArray = new int[asize];
delete[] dynamicArray;
std::cout << "mem allocated\n";
return newDynamicArray;
}
int main()
{
int asize = 130037; // dynamic array size
//asize = 12330037; // for testing second function that works
int * dynamicArray;
dynamicArray = new int[asize];
for (int i = 0; i < 100; i++)
{
std::cout << "iteration " << i << " ";
crashSystem(dynamicArray, asize);
//dynamicArray = worksOk(dynamicArray, asize);
}
std::cout << "\n";
system("PAUSE");
}
Note 2: Crashing app this way in Release mode tends to block executable by creating non existent process (checked with Process Hacker 2)