eliminating "RTTI symbol not found" problem

[mzimmers]

Hi all -

I've got a bug in my app that causes a crash. When running in debug mode, though, I get this error at the point of the crash:

RTTI symbol not found for class 'QObject'

If I understand this message, it has something to do with how the program is built. Any ideas on how I can eliminate this, so I can get a stack trace to help me find my bug?

Thanks...

[JonB]

@mzimmers
Bearing in mind I don't know about QML environment. And you really should Google RTTI symbol not found for class 'QObject', there are quite few specific hits which may be your situation. For example, it might be

I think this is a problem of GDB when it looks for RTTI of a type where a lambda is involved.

But if you want to view a QObject in a debugger you will need Qt compiled for debug as well as your own code. I don't know whether this would give that error. I manage without Qt debug libraries, but I don't get to look into Qt code.

I see @JoeCFD has posted, he probably knows a lot more than I!

[JoeCFD]

@mzimmers one possible reason is one of your classes inherits QObject, but without Q_OBJECT. Make sure that the header file has the Q_OBJECT macro declared in it.

[JonB]

@mzimmers
Bearing in mind I don't know about QML environment. And you really should Google RTTI symbol not found for class 'QObject', there are quite few specific hits which may be your situation. For example, it might be

I think this is a problem of GDB when it looks for RTTI of a type where a lambda is involved.

But if you want to view a QObject in a debugger you will need Qt compiled for debug as well as your own code. I don't know whether this would give that error. I manage without Qt debug libraries, but I don't get to look into Qt code.

I see @JoeCFD has posted, he probably knows a lot more than I!

[jeremy_k]

RTTI = Run Time Type Introspection

By any chance does the code attempt to dynamic_cast a QObject derived object? Qt has traditionally been built with RTTI turned off (-fno-rtti or similar).

[mzimmers]

Thanks for all the replies, guys. @JoeCFD my class does have the Q_OBJECT macro. @JonB I did search that exact string, but nothing I found seemed relevant to my situation. @jeremy_k I don't have any dynamic_cast.

Since this looks more like a C++ problem, I'm going to mark it as solved and post something in the C++ forum. After thinking about it, I'm going to post in the QML forum since it's a QML call that provokes this.

Thanks for looking.