Why Does My Qt Project Show a 'undefined reference to vtable' Error Despite No Virtual Methods?

Qt Linker Error: "undefined reference to vtable" [duplicate]

Error Details

The Qt linker reports an error indicating "undefined reference to vtable" for the BarelySocket class, despite the absence of any virtual methods within the class. The error persists even after excluding the QVector member variable.

Resolution

The solution to this error lies in ensuring that the project has been properly re-run through the qmake utility after adding the Q_OBJECT macro to the BarelySocket class definition. The Q_OBJECT macro requires a specific setup process, and failing to run qmake after its addition can lead to missing vtable definitions.

Proper Setup Process

To correctly include the Q_OBJECT macro and prevent the linker error, follow these steps:

1. Include the necessary Qt headers in your class definition.
2. Add the Q_OBJECT macro to the class definition.
3. Run qmake from the command line or within the development environment. This will generate the necessary Makefiles or build scripts for your project.
4. Re-compile and run your application to ensure that the linker error has been resolved.

Note: If the error persists after re-running qmake, it may indicate other issues in the codebase.

The above is the detailed content of Why Does My Qt Project Show a 'undefined reference to vtable' Error Despite No Virtual Methods?. For more information, please follow other related articles on the PHP Chinese website!