Hi guys:

I was stucked in a problem, the program can be built and run for a about 19 minutes, and then exited with code -1073740940.
I don't know where can find the code means ?
Develop environment : Qt 5.14.0 / Windows 10

After checked my code and did a lot of test , I found that when I disable some code sections, it would run for a long time.
The function was reading a block of dem data from memory, and it runs a about 60 times per second.
---------------------------code sections-------------------------------------------------------
short int* DemPreLoad::LoadDemData_Area()
{
short int* crop = (short int*)malloc(sizeof(short int) * _Terrian_Range * _Terrian_Range*4); // _Terrian_Range is const for 100
Location location = getLocation(); // According to longtitude & latitude caculate which row & col the right data in the dem data map
Location beginlocation;
int beginIndex;

beginlocation.col = location.col - _Terrian_Range;
beginlocation.row = location.row - _Terrian_Range;
beginIndex = (int)(beginlocation.col + beginlocation.row * 43200);

for (int rows = 0; rows < _Terrian_Range * 2; rows++)
{
for (int cols = 0; cols < _Terrian_Range * 2; cols++)
{
crop[cols + rows * _Terrian_Range*2] = _DataNow[beginIndex + cols];
if (demlow>_DataNow[beginIndex + cols]) demlow=_DataNow[beginIndex + cols];
if (demhigh<_DataNow[beginIndex + cols]) demhigh=_DataNow[beginIndex + cols];
}
beginIndex += 43200;
}

return crop;
}
---------------------------------------- code sections end ----------------------------------------
My questions are :
1? Where could I find the code means.
2? How could fix the problem(s).

Thanks a lot.