ifstream object declared inside a function not working on release mode - c++

Question

I am working on my first app that i´m actually going to give to someone else to use it, so i am trying to do the hole deploy process (on Qt), and create an installer after.
The problem is that a have a specific point in my code (i already discovered where), that it runs fine on Debug mode, but on Release i have no ideia what happens (it symply not run the specific function).
The problem is (just a simple example about the) that, if a declare an ifstream object in the main function, the release .exe runs just fine. When i put that object on a function, it doesnt work! I dont know what to do.
#include <iostream>
#include <reader.h>
#include <string>
#include <map>
#include <mrp.h>
#include <file_manager.h>
#include <string>
#include <facade_mrp.h>
#include <fstream>
#include <vector>
using namespace std;
void test()
{
fstream f;
f.open("C:\\Users\\user\\Documents\\Alexandre\\C++\\MRP\\build-MRP-Desktop_Qt_5_0_2_MinGW_32bit-Release\\Demandas.txt",ifstream::in);
f.close();
}
int main(int argc, char* argv[])
{
test();
return 0;
}

Answer 1

Please clarify what you mean by: "does not work". Does the program crash? Or just does it not read the contents of the file?
To troubleshoot a problem with std::ifstream, it's usually convenient to have a look at .good(), .fail() and .eof() member functions. Find out more about them in the docs.
If the problem presents in Release configuration, but not in Debug, there are usually few common culprits you should look into:
Release builds usually have -O2 or -O3 optimization levels enabled, while Debug builds don't.
Release builds are usually stored in a different file system path than Debug builds (check relative paths).
Hope this helps!