How to fix still reachable error in valgrind? - c++

Question

-----update-----
I managed to fix the issue by not exiting mid-function but returning to main and exiting there.
Can you explain why it worked?
tnx
I keep getting still reachable valgrind error on my code.
Already tried:
close file before exit, and before function readCSV ends
declare iss once, and using iss.str, iss.clear
(all destructors are default)
I think this function is causing me problems. I's called from the main function, and reads the csv file into a deque:
static std::deque<Fractal *> readCSV(const std::string &path)
{
std::deque<Fractal *> fractals;
std::ifstream ifs(path);
if (ifs.fail())
{
std::cerr << INV_INPUT << std::endl;
exit(1);
}
std::string line;
while (getline(ifs, line))
{
std::istringstream iss(line);
std::string arg;
int type, height;
getline(iss, arg, ',');
type = strToN(arg);//parse int from string, -1 if not a valid integer
getline(iss, arg, ',');
height = strToN(arg);
if (height <= 0 || height > MAX_HEIGHT)
{
std::cerr << INV_INPUT << std::endl;
deleteFractalArr(fractals);
exit(1);
}
if (getline(iss, arg, ','))
{
std::cerr << INV_INPUT << std::endl;
deleteFractalArr(fractals);
exit(1);
}
switch (type)
{
case 1:
fractals.push_front(new SCarpet(height));
break;
case 2:
fractals.push_front(new SSieve(height));
break;
case 3:
fractals.push_front(new CDust(height));
break;
default:
std::cerr << INV_INPUT << std::endl;
deleteFractalArr(fractals);
exit(1);
}
}
return fractals;
}
the deleteFractalArr is as follows:
static void deleteFractalArr(const std::deque<Fractal *> &fractals)
{
for (Fractal *f:fractals)
{
delete f;
f = nullptr;
}
}