std::filesystem crashes my app

hbatalha

I am trying to create a simple program using std::filesystem but my app is always crashing. I am on window using GCC 10.3.0, Qt 6.1.2.

#include <QApplication>
#include <fstream>
#include <filesystem>

// Driver program to test the above function
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    namespace fs = std::filesystem;

    std::ofstream of("teststxt");

    for(auto const& iter : fs::directory_iterator("binf"))
    {
        if(fs::is_regular_file(iter))
            of << iter.path().filename().string() << std::endl;
    }
    of.close();

    return a.exec();
}

If I comment out the code that uses std::filesystem it works fines.

JonB

@hbatalha
Well it doesn't look like whatever it is has anything to do with Qt. When you run in debugger what is the stack trace on "crash"?

hbatalha

@JonB

Well it doesn't look like whatever it is has anything to do with Qt.

I ran this code in Code::Blocks and it worked fine. It does look like it has to do with Qt. But I will do some more digging and what might come up

When you run in debugger what is the stack trace on "crash"?

I tried running the debugger but it doesn't even start

JonB

@hbatalha said in std::filesystem crashes my app:

I tried running the debugger but it doesn't even start

What "doesn't even start" --- the program from inside the debugger or the debugger itself?

Anyway, I don't know what "Code::Blocks" might be, or what platform you are on. I only know of using gdb with gcc (e.g. under Linux), or Qt Creator will front-end that for you. Getting the debugger working is an important part of developing.

hbatalha

@JonB

What "doesn't even start" --- the program from inside the debugger or the debugger itself?

The debugger

Anyway, I don't know what "Code::Blocks" might be, or what platform you are on.

Code::Blocks is a C/C++ IDE and I am on Windows

SGaist

Hi,

As @JonB suggested what does the debugger tell you ?
By the way, how are you starting your application ?

hbatalha

@SGaist

As @JonB suggested what does the debugger tell you ?

The debugger doesn't start

By the way, how are you starting your application ?

I don't understand what you mean?

Kent-Dorfman

@hbatalha said in std::filesystem crashes my app:

QCoreApplication

Are you sure you're using the -std=c++17 or greater on compilation?
Have you read the gcc errata on std::filesystem and its implementation differences on different platforms?

std::filesystem was a boost library prior to c++17 and has a list of features that may not be completely supported in different g++ versions on windows.

can you implement your desired behaviour using the Qt filesystem module?

JonB

@hbatalha said in std::filesystem crashes my app:

If I comment out the code that uses std::filesystem it works fines.

In addition to @Kent-Dorfman's comments. What about if you comment out the 3 lines using anything Qt (#include, QCoreApplication, a.exec())? If that still misbehaves you have a fully non-Qt exemplar.

SGaist

@hbatalha said in std::filesystem crashes my app:

I don't understand what you mean?

Are you starting it from Qt Creator ? The command line ?

hbatalha

@SGaist

Are you starting it ? The command line ?

from Qt Creator